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Vaccine trial

A vaccine trial is a clinical trial that aims at establishing the safety and efficacy of a vaccine prior to it being licensed.

A vaccine candidate drug is first identified through preclinical evaluations that could involve high throughput screening and selecting the proper antigen to invoke an immune response.

Some vaccine trials may take months or years to complete, depending on the time required for the subjects to react to the vaccine and develop the required antibodies.

Preclinical stage
Preclinical development stages are necessary to determine the immunogenicity potential and safety profile for a vaccine candidate.

This is also the stage in which the drug candidate may be first tested in laboratory animals prior to moving to the Phase I trials. Vaccines such as the oral polio vaccine have been first tested for adverse effects and immunogenicity in monkeys as well as non-human primates and lab mice.

Recent scientific advances have helped to use transgenic animals as a part of vaccine preclinical protocol in hopes to more accurately determine drug reactions in humans. Understanding vaccine safety and the immunological response to the vaccine, such as toxicity, are necessary components of the preclinical stage. Other drug trials focus on the pharmacodynamics and pharmacokinetics; however, in vaccine studies it is essential to understand toxic effects at all possible dosage levels and the interactions with the immune system.

Phase I
The Phase I study consists of introducing the vaccine candidate to assess its safety in healthy people. A vaccine Phase I trial involves normal healthy subjects, each tested with either the candidate vaccine or a "control" treatment, typically a placebo or an adjuvant-containing cocktail, or an established vaccine (which might be intended to protect against a different pathogen). The primary observation is for detection of safety (absence of an adverse event) and evidence of an immune response.

After the administration of the vaccine or placebo, the researchers collect data on antibody production, on health outcomes (such as illness due to the targeted infection or to another infection). Following the trial protocol, the specified statistical test is performed to gauge the statistical significance of the observed differences in the outcomes between the treatment and control groups. Side effects of the vaccine are also noted, and these contribute to the decision on whether to advance the candidate vaccine to a Phase II trial.

One typical version of Phase I studies in vaccines involves an escalation study, which is used in mainly medicinal research trials. The drug is introduced into a small cohort of healthy volunteers. Vaccine escalation studies aim to minimize chances of serious adverse effects (SAE) by slowly increasing the drug dosage or frequency. The first level of an escalation study usually has two or three groups of around 10 healthy volunteers. Each subgroup receives the same vaccine dose, which is the expected lowest dose necessary to invoke an immune response (the main goal in a vaccine – to create immunity). New subgroups can be added to experiment with a different dosing regimen as long as the previous subgroup did not experience SAEs. There are variations in the vaccination order that can be used for different studies. For example, the first subgroup could complete the entire regimen before the second subgroup starts or the second can begin before the first ends as long as SAEs were not detected. The vaccination schedule will vary depending on the nature of the drug (i.e. the need for a booster or several doses over the course of short time period). Escalation studies are ideal for minimizing risks for SAEs that could occur with less controlled and divided protocols.

Phase II
The transition to Phase II relies on the immunogenic and toxicity results from Phase I in a small cohort of healthy volunteers. Phase II will consist of more healthy volunteers in the vaccine target population (~ hundreds of people) to determine reactions in a more diverse set of humans and test different schedules.

Phase III
Similarly. Phase III trials continue to monitor toxicity, immunogenicity, and SAEs on a much larger scale. The vaccine must be shown to be safe and effective in natural disease conditions before being submitted for approval and then general production. In the United States, the Food and Drug Administration (FDA) is responsible for approving vaccines.

Phase IV
Phase IV trials are typically monitor stages that collect information continuously on vaccine usage, adverse effects, and long-term immunity after the vaccine is licensed and marketed. Harmful effects, such as increased risk of liver failure or heart attacks, discovered by Phase IV trials may result in a drug being no longer sold, or restricted to certain uses; examples include cerivastatin (brand names Baycol and Lipobay), troglitazone (Rezulin) and rofecoxib (Vioxx). Further examples include the swine flu vaccine and the rotavirus vaccine, which increased the risk of Guillain-Barré syndrome (GBS) and intussusception respectively. Thus, the fourth phase of clinical trials is used to ensure long-term vaccine safety.

title: Vaccine trial


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Montgomery Canal

The Montgomery Canal (Camlas Trefaldwyn), known colloquially as "The Monty", is a partially restored canal in eastern Powys and northwest Shropshire. The canal runs 33 mi from the Llangollen Canal at Frankton Junction to Newtown via Llanymynech and Welshpool and crosses the England–Wales border.

Originally, the canal from Llanymynech to Newtown was known as the Montgomeryshire Canal. It was named after the county of Montgomeryshire that it ran through and it was divided into Western and Eastern branches which met at Garthmyl. At Carreghofa Locks near Llanymynech, the Montgomeryshire Canal connected to the Llanymynech Branch of the Ellesmere Canal. These elements of the present-day Montgomery Canal were unified when they each became part of the Shropshire Union system: the Ellesmere Canal in 1846, the Eastern Branch in 1847 and the Western Branch in 1850.

The canal fell into disuse following a breach in 1936 and was officially abandoned in 1944. With the revival of canal use in the late 20th century, the Western and Eastern branches of the Montgomeryshire Canal and the Llanymynech Branch of the Ellesmere Canal together became known as the Montgomery Canal although the canal does not, and never did, go to the town of Montgomery.

At present only 8 mi from Frankton Junction to Crickheath Bridge is navigable and connected to the rest of the national Canal & River Trust network. Separately, a short stretch at Llanymynech and a central section of the canal around Welshpool are also navigable though isolated from the national canal network. Ongoing restoration work continues to expand the navigable sections.

History

The Montgomeryshire Canal was devised with a different purpose from most other canals of the time. Whereas other canals could generate sufficient revenue from cargo carrying to be financially viable, the Montgomeryshire was planned to serve a more rural area which would not offer such opportunities. Instead, the primary purpose of the canal was to transport lime for agricultural purposes which would allow the Upper Severn Valley to become better agricultural land. As a result, the promoters of the canal included local landowners who hoped to achieve a return on their investment through greater crop yields rather than relying upon share dividends.

The original 1792 proposal for the Montgomeryshire Canal was for a route from Llanymynech, where it would join the proposed Llanymynech Branch of the Ellesmere Canal, to Welshpool. By 1793, it had been decided that the canal should continue through to Newtown. The canal was authorised in 1794 by an act of parliament entitled "An act for making a navigable Canal from or near Porthywain Lime Rocks in the parish of Llanyblodwell, in the county of Salop, to or near Newtown, in the county of Montgomery, and also certain collateral Cuts from the said Canal." The company was authorised to raise £72,000 from shares and a further £20,000 if required. John Dadford was appointed Engineer while his brother Thomas Dadford Junior was appointed his assistant. There had been suggestions in 1793 for a connecting canal between Garthmyl and the Leominster Canal at Woofferton. It would have been 40.25 mi long but the plan came to nothing.

By February 1796, parts of the canal were completed and the first boat, named the Royal Montgomery, was launched into the canal near Welshpool amidst great celebrations. In July 1797, the connection to the Ellesmere Canal at Llanymynech was opened although the Llanymynech branch was still suffering from problems with leakage. A month later, the canal had reached Garthmyl providing 16 mi of navigable canal from Llanymynech but stopping 7 mi short of Newtown. In early 1797 John Dadford had resigned his post in order to pursue a career in America and, at the suggestion of Thomas Dadford, had been replaced by his father Thomas Dadford senior. During construction, there had been problems with both the Berriew Aqueduct and the Vyrnwy Aqueduct where one arch had collapsed. The management committee were unhappy with this and the engineer William Jessop was called in to advise but he explained that such issues were merely teething problems and allayed their fears. To reach Garthmyl, £71,000 had been spent. The canal thus far included 13 locks: four descending between Carraghofa and Burgedin and nine rising from there to Garthmyl. It also included a level branch to Guilsfield, some 2.25 mi long.

Although conceived as a means to serve agricultural communities, trade on the canal developed steadily. There were a number of quarries in the Llanymynech area which delivered limestone to the canal for transport to kilns at Belan and elsewhere. Grain prices rose from 1800 onwards and there was a large demand for lime as a fertiliser so that the Welsh hill-lands could be enclosed and developed for agriculture. Once the Chirk and Pontcysyllte aqueducts were opened on the Ellesmere branch to Llangollen, there was an easy route for the transport of coal used in the lime kilns to produce fertiliser. Other cargoes included stone for building, roofing slates, timber and bark. At its outset, the Earl of Powis had been one of the principal shareholders in the canal; he and his son, Lord Clive, were both landowners and owners of quarries and mills along the canal. The first dividend of 2.5 per cent was paid in 1805 and thereafter, a dividend was paid in most years while the canal remained independent at rates up to 5.5 per cent. Volumes of limestone carried rose from 14,082 tons in 1806 to 44,592 tons in 1814 while carriage of slack coal rose from 6,757 tons to 11,560 tons over the same period. There was a significant drop in volumes with the end of the Napoleonic Wars but trade had picked up again by 1820.

Western extension
A lack of capital and income prevented completion of the canal and Garthmyl remained the terminus for 20 years but by 1812, Newtown was experiencing significant growth and there were calls to extend the route southwards, either as a canal from Garthmyl to Newtown or as a canal to Bryn-derwen and a tramroad beyond that. A meeting of the shareholders held in October 1813 narrowly voted to press on and Josias Jessop was asked to survey the route. His initial estimate was £28,268 although some of the committee later thought that he had forgotten to include the cost of puddling and lining the canal. The company agreed to put a Bill before Parliament to obtain the necessary powers but factions developed within the shareholders with some fearing that they might lose their investment if the canal were completed. Heated meetings were held in September 1814 and January 1815 at which neither side was entirely successful but on 3 February 1815, the company agreed that the new section would effectively be built by a separate company with its own committee and accounts.

The old company would be known as the Eastern Branch with the new company responsible for the Western Branch. Any profits that the Eastern Branch made above 5 per cent would be used to fund the extension and on completion, the two branches would be jointly managed. Surpluses from the Eastern Branch would continue to be transferred to the Western Branch until it was able to pay a 5 per cent dividend at which point the two companies would be formally amalgamated. This was enshrined in an act of Parliament (55 Geo. 3. c. lxxxiii) obtained in 1815 which authorised the raising of £40,000 in new shares to complete the canal. The new company kept themselves separate failing to notify the Eastern Branch how the work was progressing. Under the supervision of John Williams, the resident engineer, who used Jessop's plans, the new canal was completed in March 1819 although it was not formally declared to be complete until 7 December 1821. It descended through six locks from Newtown and was supplied with water from the River Severn by a 24 ft water wheel and a backup steam engine. An additional supply came from a weir and feeder at Penarth. The six locks were each 8 ft deep with the cut being 4 ft deep and 15 ft wide at the bottom. As a result of the Western Branch needing to be profitable to allow the branches to merge, a higher tonnage charge was imposed on the Western Branch. On 23 June 1821 a further act of Parliament was obtained to alter the line of the Tanat feeder and to make a navigable cut from the Guilsfield Branch. This act also stipulated that the consolidation of the Eastern and Western branches would no longer be automatic but would require the consent of the proprietors of each and clarified that the commencement of the Eastern branch was to be taken as the distance of thirty-five yards from the sill of the upper gate of the higher of the two Carreghofa locks. This alteration to the line of the Tanat feeder resulted in it now supplying the pound above the Carreghofa locks whereas it had previously fed the canal below the locks.

The cost of the Western Branch was £53,390 which was well in excess of the £22,300 which had been raised by issuing new shares. The company had borrowed £6,000 from the Exchequer Bill Loan Commissioners and the rest from various others, the majority coming from William Pugh. Income on the new branch was meagre so that the company could not meet the interest payments on the loans and factions developed. One group was led by Pugh who complained that the engineer Williams had muddled the accounts since the canal had opened and another group thought that Pugh had borrowed money beyond the powers granted by the act of Parliament. They wanted the Exchequer Bill Loan Commissioners to investigate the company's financial position. However both parties agreed that George Buck, who had been the engineer for the Eastern Branch since 1819, should become engineer and clerk and he was appointed to this post in December 1832 with a mandate to investigate the accounts.

Buck presented his findings in November 1833 but the meeting took no action as Pugh was absent. Buck moved on the following month to assist Robert Stephenson on railway projects. Pugh then paid off both the capital and interest of most of the other creditors resulting in the company owing him £38,106 which was split into a mortgage for £25,000 and £13,000 in shares. He then obtained his own act of Parliament to authorise his position and to allow the company to raise their tolls. By June 1835, the Western Branch declared that receipts were sufficient to pay the interest on all mortgages but there is no evidence that any dividends were ever paid on the shares. The two branches remained separate companies throughout their life.

Shropshire Union takeover
Major structural repairs to the Vyrnwy aqueduct had been required in 1823 when all of the arches were strengthened by iron bands under the supervision of Buck. Otherwise, the Eastern Branch continued to be relatively prosperous apart from a brief dip during a trade recession between 1840 and 1844. This was partly due to the late arrival of railways in the area. The Western Branch, in contrast, was hampered by the fact that nearly all of the traffic was in one direction towards Newtown with very little goods travelling in the opposite direction.

The prospect of railway competition arrived in the 1840s and in 1845 the company was approached by the proposed Shrewsbury to Newtown Railway to work out a deal. The company responded by setting up a subcommittee in January 1845 to consider how best to protect themselves from such competition. Meanwhile, the London and Birmingham Railway were negotiating with the Ellesmere and Chester Canal who were planning to convert some of their canals into railways. They asked William Cubitt to investigate whether their own canal could also be converted but that plan was dropped soon afterwards as the Ellesmere and Chester offered to buy the canal for £110 per share and the offer was accepted. The Ellesmere and Chester Canal obtained an act of Parliament to enable them to become the Shropshire Union Railways and Canal Company and to take over several canals including both the Eastern and Western Branches of the Montgomeryshire Canal. The Eastern Branch was formally transferred to become part of the Shropshire Union on 1 January 1847 with the company receiving £78,210 of which £7,920 was in shares in the new company and the rest was in cash. The Western Branch remained under Pugh's control for three more years but was bought for £42,000 on 5 February 1850 although some £7,000 of this cannot be traced from the accounts.

The Shropshire Union company had negotiated with several railway companies who had initially been rivals but on 1 January 1846, they had all amalgamated to become the London and North Western Railway (LNWR). The Shropshire Union had obtained powers in their enabling act to build railways and thus became a threat to the London and North Western Railway who offered to lease the Shropshire Union in the autumn of 1846. This was formalised by an act of Parliament in June 1847 although the powers were not fully implemented until 25 March 1857. Part of the deal was that the Shropshire Union would drop its aspirations to build railways but in return, would have a free hand to run the canals which they did vigorously. The LNWR applied for powers to build a railway linking Shrewsbury, Newtown, Welshpool and Oswestry in 1853 but after negotiation with the Great Western Railway, withdrew the bill and it was they who built the Oswestry and Newtown Railway which was completed on 10 June 1861. The plan was supported by some of the former Montgomeryshire Canal shareholders, who were disappointed that the sale of the canal to the Shropshire Union had not resulted in it being converted into a railway.

Decline
Although the Shropshire Union had a fairly free hand in running the canals, the goods that could be carried were restricted by the terms of their lease and the canals gradually became less profitable. Consideration was given to closing the Weston Arm in 1875 and again in 1885 but no action was taken. The idea of closing the whole of the former Montgomery Canal was considered in 1887 but study of the figures revealed that it was still making a small profit of £432 per year and so it was reprieved. In May 1917, the Weston Arm suffered a breach at Dandyfield which it was estimated would cost £14,000 to repair. Thereafter, the arm was only open for about 0.75 mi to Hordley wharf but there were complaints and the issue was referred to the Board of Trade. They ruled in 1920 that repairs were not justified and so the arm stayed closed. The Shropshire Union was absorbed by the London and North Western Railway in late 1922 and itself became part of the London, Midland and Scottish Railway (LMS) under the 1923 grouping of the railways. Another breach of the canal occurred a mile (1.6 km) from Frankton Junction on 5 February 1936. The owners paid compensation to George Beck, the main user of the canal, and applied for a warrant of abandonment but this was refused. The LMS finally obtained an act of abandonment in 1944 which gave them powers to close the whole of the canal from Frankton Junction southwards, including the Weston Arm, as part of a plan to close 175 mi of canal.

The act of abandonment allowed bridges to be lowered although none of the route of the canal was sold at that time. The Transport Act 1947 resulted in the nationalisation of the railways and canals with control of the Montgomery Canal passing to the British Transport Commission in 1948 and ultimately to British Waterways in 1963 following the passing of the Transport Act 1962. The Transport Act 1968 classified canals into one of three categories and the Montgomery Canal became a Remainder Waterway meaning that British Waterways could only carry out certain statutory work on it. As a result of the act, the final 2 mi to Newtown were sold off.

Restoration
Since 1969, when the canal through Welshpool was threatened by a proposed road bypass, the canal has been gradually – but so far only partially – restored for use by pleasure boaters. In some places, the canal has been filled in, roads have been built over the channel, bridges have been lowered and infrastructure such as pipes and manhole covers have been built in the canal bed presenting several obstacles to restoration. The end section from Freestone Lock to Newtown is dry and no longer in Canal & River Trust ownership.

Completed restoration
In 1969, there were plans to convert the bed of the canal through Welshpool into a road and the Welshpool By-Pass Action Committee was formed to oppose this. They requested the help of the Shropshire Union Canal Society who organised a "Big Dig" at Welshpool which was attended by over 200 volunteers who cleared a section of the canal. The Shropshire Union Canal Society had already begun campaigning for the restoration of the canal and in the run-up to the event, members attended council meetings, mounted displays in the town and organised a visit to Market Drayton for Welshpool Town Council, to see another section of the Shropshire Union where progress was being made. Key players included Graham Palmer, the organiser of the London and Home Counties Working Party Group of the Inland Waterways Association. They published a journal called Navvies Notebook which co-ordinated volunteer activity on the canals across Britain and within a year had become the Waterway Recovery Group. It was agreed that volunteers would tackle the section from Welshpool Lock northwards to Mill Lane. Despite high-level opposition to restoration by British Waterways, at local level they agreed to shut off the feed to the southern section and lower the water level so that water could be pumped out of the section through Welshpool, rather than discharged into the Lledan Brook.

Welshpool Borough Council refused the use of their tip for material removed from the canal but a local farmer called W Davies offered the use of his land. Buttington Contractors offered items of equipment and the event was planned for the weekend of 18 and 19 October 1969. Some 100 volunteers were expected and pumping began on Friday evening. The Severn River Board removed over 700 fish on Saturday morning and numbers attending exceeded expectations. Despite warnings by British Waterways not to touch it, the Lledan Brook flood paddle was opened to assist in the drainage of the canal and over 200 people set to work using hand tools and borrowed equipment including a mobile crane, ten dumper trucks, four 7-ton tipper trucks, three JCB diggers and a Hy-Mac long arm excavator. Brian Haskins, the British Waterways area engineer from Northwich, visited the site and overlooked the use of the flood paddle. There was considerable interest from the townspeople and the number of onlookers became a bit of a hazard. The cleared canal was refilled on the Sunday and the Mayor and Mayoress rode along the section on a cruiser that had been trailed from Market Drayton. The canal route for the bypass was subsequently rejected by a public enquiry.

The Inland Waterways Amenity Advisory Council published a review on 20 August 1971 which assessed the potential of the "Remainder Waterways" which had been defined in the Transport Act 1968. This advocated the complete restoration of the Montgomery Canal among other suggestions. The Prince of Wales announced a plan to restore 7 mi of the canal to amenity waterway standards in October 1973. This was achieved through the Prince of Wales Committee of the House of Lords and was to be managed by the Shropshire Union Canal Society. The scheme was also backed by the Variety Club of Great Britain who wanted to use the restored canal as a recreational base for the benefit of handicapped children. The Prince formally opened Welshpool Town Lock on 23 May 1974 as the scheme got under way. Despite the progress being made, the Welsh Office approved a scheme in 1976 to construct a bypass road at Arddleen which would have crossed the canal at low level and culverted the canal beneath it. The Inland Waterways Association and the Shropshire Union Canal Society worked together to get the scheme changed and by mid-1978, an engineering solution had been worked out but the costs involved brought delays to the restoration.

The next threat to restoration occurred in 1979 when following the collapse of James Callaghan's Labour government and the election of Margaret Thatcher, economic conditions were tight. Powys County Council were faced with the cost of repairing and upgrading bridges over the canal and wanted to lower bridge 96, below Carreghofa bottom lock, to remove a weight restriction. They applied to the High Court for a "writ mandamus" which put the onus on the court to decide who was responsible for the costs. Again, the restoration movement objected but the court ruled in favour of lowering the bridge. British Waterways objected on the basis that restoration was already ongoing. Soon afterwards, the Secretary of State suggested that a note should be added to the Shropshire County structure plan indicating that the line of the canal should be protected but the lowering of the bridge went ahead. The Powys structure plan was amended in early 1982 to protect the canal from bridge 120, located to the south of Welshpool, northwards. However within weeks, British Waterways announced that the future restoration beyond the locks at Frankton and Carreghofa, was uncertain. The Restoration Trust met with Sir Frank Price, chairman of British Waterways, on 5 April 1982 and it was agreed that an economic assessment of the viability of restoration should be carried out and completed by October.

By 1985, the environmental lobby was growing and in order to avert a situation where boaters and environmentalists clashed, the Manpower Services Commission funded a scheme to document the flora and fauna of the unrestored canal. It also included an experimental off-line nature reserve which could provide a habitat for rare or interesting plants and the first such reserve was built at Rednal. The concept was a success and paved the way for other reserves that allowed restoration to proceed, both on the Montgomery Canal and on other canals where there were sensitive environmental concerns. Montgomeryshire County Council committed £1 million to canal restoration over a five-year period as British Waterways submitted a private bill to Parliament to authorise restoration of the whole canal. The restoration also benefited from a legacy of £200,000 left by Humphrey Symonds via the Inland Waterways Association, specifically for the Montgomery Canal. Frankton Locks were reopened on 12 September 1987 by the Prince of Wales when he announced that volunteers had worked for 12,000 man-hours on the project and that the value of this contribution was £200,000.

The British Waterways Act 1987 became law on 17 December 1987, and authorised the restoration of the canal from Newtown Pumping Station to Frankton Junction, including the Guilsfield and Weston arms. It formalised the change of name to the Montgomery Canal and the construction and maintenance of nature reserves. It also specified that any refurbished or new sections of the canal, when they were brought into use, would automatically be designated as Remainder Waterways using the classification from the 1968 Act. A second Act was obtained on 29 July 1988 to undo the provisions of the London Midland and Scottish Railway (Canals) Act 1944 which had removed the right of navigation and prohibited such use. The new Act reinstated the right to allow navigation on any sections open at the time the Act was obtained and on any sections subsequently re-opened. British Waterways was succeeded by the Canal & River Trust in 2012.

Gallowstree Bridge was opened by David Suchet on 7 June 1992. The canal from Frankton Locks to the River Perry crosses Perry Moor and historically, the bed had no puddling at this point relying instead on the water table of the peat moor to retain the water. Modern agricultural methods had changed this and a new lining using butyl, concrete and gabions had to be created during 1994. Shrinkage of the peat had also caused subsidence of the canal and a new lock was built with a drop of 2.5 ft. On 3 June 1995, the restored section between Frankton Locks and the aqueduct over the River Perry was opened and the new lock was named the Graham Palmer lock, after the man who had been instrumental in so much canal restoration through the creation of the Waterway Recovery Group. The section onwards to Queen's Head, a hamlet on the A5 trunk road, followed on 21 September 1996 extending the length of navigable canal connected to the national network to 4 mi. The 2.5 mi section from Maesbury to Redwith benefitted from European Regional Development funding awarded in 2000 but there were fears that restoration might be hampered by the designation of large lengths of the canal in Powys as a Site of Special Scientific Interest (SSSI) by the Countryside Council for Wales. Negotiations took place between the Trust, the Council and English Nature to ensure that this did not happen and an agreement was eventually worked out in 2005 which would ensure that the flora and fauna would be protected by off-line nature reserves, to allow full navigation on the main line of the canal.

In the autumn of 2002 work was started on the restoration of Newhouse Lock, the penultimate lock on the southern section still owned by British Waterways. Soon after work started, it became evident that there were structural problems which had not been apparent when the first engineering inspection had been carried out. Further funding was obtained and the quality of the work done by volunteers resulted in them completing some of the tasks originally assigned to professionals. £250,000 was spent on the project, significantly less than the revised budget, and the contribution of volunteer labour was valued at £45,000. The restoration was completed six months ahead of schedule in 2006 and the lock was opened officially on 25 June 2006 by Lembit Opik MP in conjunction with the Annual Montgomery Dinghy Dawdle. The restoration of the lock was named Welsh Project of the Year by the Royal Institution of Chartered Surveyors in May 2007. This completed the restoration of all of the locks on the section of the canal owned by British Waterways and was the eleventh lock on the Welsh section of the canal to be restored by the Shropshire Union Canal Society.

In 2003, the 3 mi section from Queen's Head to Gronwen Wharf was reopened opening the canal through the village of Maesbury Marsh. The 875 yd section from Gronwen Wharf to Redwith Bridge was filled with water in October 2007. Rare flora and fauna were accommodated by the construction of an off-line nature reserve on land leased by British Waterways for 50 years. The cost of the reserve added an extra £250,000 to the projected cost and this was partially funded by the Heritage Lottery Fund and EU Interreg funds. Restoration then started on the 490 yd section onwards to Pryces Bridge. Rebuilding of the channel involved the laying of over 40,000 concrete bricks and the use of a Bentonite membrane. The refurbished channel was opened on 19 July 2014 by Owen Paterson, the MP for North Shropshire, but because there is no winding hole at the end of it, the limit of navigation remained at Gronwen Wharf for most boats.

In 2007, restoration of Crickheath Basin was started by the Shropshire Union Canal Society though in 2008, work was postponed due to land ownership issues. Between 2014 and 2022, the section of canal between Pryces Bridge and Crickheath Bridge was restored. This was aided by the award of a National Lottery grant in 2016. The section was officially opened on 2 June 2023. As there is a winding hole at Crickheath Basin, just north of Crickheath Bridge, re-opening allows navigation of the canal between Redwith Bridge and Crickheath Bridge.

Current restoration projects
Restoration of the section of canal between Crickheath Bridge and Schoolhouse Bridge started in 2023. A separate project to rebuild the dropped Schoolhouse Bridge was also completed in 2024. The two projects will not in themselves allow the section of canal between Crickheath Bridge to Schoolhouse Bridge to be re-opened to navigation as there is no winding hole on this section.

A joint bid by Powys County Council and the Canal and RIver Trust for funding to further restore the canal between Llanymynech and Arddleen succeeded when in October 2021, the Chancellor of the Exchequer, Rishi Sunak, announced the award of £16 million for the purpose as part of his annual budget. The award comes from the government's 'Levelling Up Fund', and covers restoration of 4 mi in Wales. The money has to be spent by the spring of 2024 but will not include the restoration of two dropped bridges near Ardleen.

Restoration is being carried out by a partnership of the Montgomery Waterway Restoration Trust and the national Canal & River Trust (who own the canal and are its navigation authority). As of 2023, Crickheath Basin remains the limit of navigation for larger powered craft on the northern section of the canal which is connected to the Llangollen Canal and the wider Canal & River Trust network at Frankton Junction. A very short section of navigable canal exists in Llanymynech and a separate longer navigable section operates in the Welshpool area; however these two sections are not connected to any other navigable canal and are therefore 'isolated'.

Architecture
The lock gear on the Eastern Branch of the Montgomeryshire were of a different design to those on other canals. Whereas most other canal locks have culverts in the side walls to fill and empty the lock, with paddles opening and closing vertically, the locks on the Montgomeryshire were designed with a culvert in the base of the canal with the paddle sliding horizontally over the culvert. During operation, this can lead to a large whirlpool being observed. To operate the paddle, the winding gear is purely a geared design rather than rack and pinion. An effect of this is that there is no pawl to be operated and the paddles cannot be accidentally dropped shut. The paddle gear was designed by George W. Buck, who was appointed Engineer of the Eastern branch in 1819, and Clerk to the Western branch in 1822.

Many of the lock gates on the Montgomeryshire Canal were replaced with cast iron gates. These gates were curved with tubular cast iron balance beams. The last surviving pair were removed from Welshpool and taken to Stoke Bruerne Canal Museum in the early 1970s.

Bridge numbers on the Montgomery sections of the canal continue on from the Llanymynech Branch of the Ellesmere Canal at Frankton Junction. The first bridge on the Montgomery Canal (Lockgate Bridge) is therefore number 70, the numbering beginning at Hurleston Junction. Because of this, the Llangollen Canal has two separate series of bridge numbering, one ending at Frankton Junction and the other beginning at Frankton Junction.

Nature conservation
In the years following the closure of the canal, wildlife flourished. The whole of the Welsh section and parts of the English section (notably the section from the Aston Locks to Keeper's Bridge) were designated as Sites of Special Scientific Interest (SSSI). The notable wildlife includes Floating Water Plantain and Grass-wrack pondweed.

To preserve the wildlife, nature reserves have been created at points along the canal. These include Rednal Basin, most of the Weston Branch and a specially constructed reserve alongside the Aston Locks. Some winding holes have been given over to nature with the one adjacent to Crofts Mill Lift Bridge having had boat barriers installed and the one adjacent to Park Mill Bridge having been allowed to become overgrown. A maximum of 1,250 boats per year are allowed passage on the navigable section in England (i.e. that part connected to the Llangollen Canal). In addition, there are stricter speed restrictions than normally found on British canals, for example, 2 and 3 mph on the navigable and connected part.

Towpath
The towpath of almost all the canal is used as a footpath. The section between Pool Quay Lock and Newtown forms part of the Severn Way. Shorter sections south of Llanymynech and Pool Quay are followed by the Offa's Dyke Path.

Frankton Junction to Carreghofa
This section was originally the Llanymynech branch of the Ellesmere Canal but since the passing of the British Waterways Act 1987, it is officially the first section of the Montgomery Canal. The previous history is reflected in the numbering of the bridges which start from 70 following on from a sequence which begins at Hurleston Junction where the Llangollen Canal meets the main line of the Shropshire Union Canal. The section of the canal from Frankton Junction to Gronwen Wharf (just north of Bridge 82) is navigable by narrowboat.

Access through the locks at Frankton Junction is strictly controlled and must be booked in advance. The locks are operated by a Canal and River Trust lock-keeper and passage was only allowed between 09:00 am and 12:00 noon in 2020. The number of boats using the locks is restricted to a maximum of twelve in either direction on any one day and having passed down the locks onto the canal, boaters must stay for a minimum of one day and a maximum of 14. Repeat visits cannot be made within six weeks of leaving the canal. The locks consist of a two-chamber staircase lock and two single locks. Alongside the locks are several canal buildings including a boatbuilder's house. The remains of a dry dock can be seen in the garden and it was here that the grain boat Cressy was converted for leisure use in 1929 by Jack Beech. The boat was bought by L.T.C. Rolt in 1939, who used it to tour the decaying canal network and was instrumental in the setting up of the Inland Waterways Association. A plaque commemorating this was attached to the lock entrance and unveiled by his widow, Sonia Rolt, on 17 January 2009.

The now-infilled Weston Branch, which terminated at a wharf at Weston Lullingfields branches off between Frankton Locks and Lockgate Bridge. Only a short section remains, part of which is used for mooring and part as a nature reserve. There is a Canal & River Trust amenity block alongside. Just beyond the junction is Lockgate Bridge (70), a red-brick humped-back road bridge dating from 1785 which remains almost in its original state. It is a grade II listed structure.

The canal passes through a peat bog which has been drained since the construction of the canal. This lowering of the water level has meant that during restoration the canal had to be lined to prevent leakage and a new lock was required to lower the water level. This lock was named Graham Palmer Lock after the founder of the Waterway Recovery Group. The Perry Aqueduct crosses the River Perry and was replaced during restoration. The old aqueduct had three small arches and restricted the flow on the river in flood conditions. As it was in a poor state of repair, it was replaced by a single span steel structure. Beyond the aqueduct, the canal is very straight as a diversion was built in 1822. (The original route of the canal had followed a less direct path at the insistence of one of the Proprietors, who wanted the canal to serve his Woodhouse Estate.)

Rednal Basin was originally used for transshipment between the canal and the Chester and Shrewsbury Railway. This finished in the 1850s and it subsequently served a bone mill. Although the link to the basin still exists and there is a swing bridge over the entrance, it is not used for boats as it is a nature reserve. At Queen's Head the canal passes under both the old and the new A5 road. There are mooring spaces and some Canal & River Trust buildings at Queen's Head. Following Queen's Head are the three Aston Locks. The top lock has a nature reserve alongside, built during restoration.

The canal passes through Maesbury Marsh, a village built largely alongside the canal. Canal Central, an environmentally-friendly building incorporating a post office, shop, tearoom, accommodation and bike and canoe hire was built alongside the canal near the village (just to the west of Spiggots Bridge) in 2006. Mooring is available along sections of the canal at Maesbury Marsh. Bridge 81 is a lift bridge, which requires a windlass to operate, and immediately to its west, the Mill Arm (or Peate's Branch) has been restored for much of its length giving access to a boatyard and private moorings.

The section of the canal from Gronwen Wharf to Redwith Bridge (No. 83) was re-opened in October 2007. In 2014, restoration of the section from Redwith Bridge to Pryces Bridge (No. 84) was completed. Redwith Bridge had been lowered after the canal's closure but has been rebuilt and is now capable of taking narrowboats underneath once again. In 2023, the canal was re-opened from Pryces Bridge to Crickheath Wharf, just north of Bridge 85.

The section of the canal from Crickheath Wharf through Pant to Llanymynech is dry but restoration continues to take place to close the gap with the next navigable section. In this section, the demolished Schoolhouse Bridge is being replaced but no other bridges need to be replaced and there are no locks. Through Pant, the canal ran alongside the Oswestry and Newtown Railway which later became part of the Cambrian Railways network. The Cambrian Railways Trust has restored a short section of the line between Llynclys and Pant and has built a halt at Penygarreg Lane near to the canal.

Since 2006, a short section either side of Llanymynech has been navigable and boats can turn around at a winding hole at each end. The wharf at Llanymynech has also been restored. Canal trips are provided on this Llanymynech stretch by the narrowboat George Watson Buck. As the canal passes underneath Llanymynech Bridge it passes from Shropshire, England into Powys, Wales.

The section of the canal from just after Pant through Llanymynech to Carreghofa is in water although Carreghofa Lane now crosses the canal just to the north of Walls Bridge (No. 93) and this new crossing (built after the canal's closure) obstructs the canal.

Wern Aqueduct was built after the canal was originally opened to allow a newly constructed branch of the Shropshire and Montgomeryshire Railway to pass below. A temporary diversion of the canal was put in place to allow construction of the aqueduct and the entrances to the diversion remain visible.

A feeder from the River Tanat enters the canal above Carreghofa Locks. Built in 1822 by the Montgomeryshire Canal Company, it originally fed water between the locks so that none could enter the Ellesmere Canal. When the canals were united, the feeder was diverted to enter the canal above the locks so that the lowest pound of the former Ellesmere Canal also gained from the feeder.

The end of the Llanymynech Branch of the Ellesmere Canal joins end-on to the Eastern Branch of the Montgomeryshire Canal at Carreghofa Locks.

Eastern Branch
The section of the canal from Carreghofa to Arddleen is in water although several bridges have been lowered.

Between the two Carreghofa Locks was a side pond. This was necessary as the pound between the locks is short.

Near the Vyrnwy Aqueduct, arches were built in the embankment of the canal to provide protection from flooding of the River Vyrnwy. The aqueduct itself has been repaired and strengthened in the 1820s, 1890s and 1970s. It sometimes can be seen to leak into the River Vyrnwy though the leaks self-heal. Unlike the nearby Chirk Aqueduct and Pontcysyllte Aqueduct, which have cast iron troughs, the Vyrnwy Aqueduct is built of stone and is puddled. The weight of this structure led to it being strengthened with tie bars and girders in the 1820s.

Bridges 102 and 103 carry a major road and have been lowered since the canal was closed. To restore navigation, lowering of the pound by addition of an extra lock has been proposed.

The section of the canal from Arddleen to Refail (Efail-Fach) Bridge is navigable.

The Guilsfield Arm never actually reached Guilsfield. The arm was 2.25 mi long with a wharf at its terminus. It was level, with no locks or tunnels, and this was achieved by a cutting 600 feet long and up to 20 feet deep. Today the arm is cut off from the main line by a lowered bridge. A short section has been made into a nature reserve and beyond that, the arm is dry.

The pound below Burgedin Bottom Lock is the sump pound of the canal, the Eastern Branch of the Montgomeryshire being filled by lockings from the Ellesmere, the Tanat feeder at Carreghofa and a feeder from the River Rhiw at Berriew.

The canal through Welshpool was one of the first sections to be restored in 1969 when it was proposed that the route of the canal be used for a bypass. Welshpool Town Lock had gates made of cast iron when the canal was closed. These were removed, taken to Stoke Bruerne Canal Museum and replaced by gates of a standard design.

Western Branch
The section of the canal from Refail (Efail-Fach) Bridge to Freestone Lock is in water and heads in a generally south-westerly direction. Several bridges have been lowered including bridges under the A483 which runs in the same direction as the canal traversing it in places. At Brynderwyn, there is a lock with a whitewashed cottage, once the home of the lockkeeper. To the north of the lock was Brynderwyn Wharf, once a coal wharf, and the towpath briefly changes from the eastern side to the west between bridges 145 and 146 to accommodate it. Several of the bridges on this section of canal are made from cast iron from nearby Brymbo. Glanhafren Bridge, no. 143, carries the date 1889 and has ornate balustrades made from cast iron while bridge 147, which carries Brynderwen New Road over the canal to the north of Abermule, dates from 1853.

To the south of Abermule, the A483 cuts across the bed of the canal at an angle. This section of road is relatively recent as the road crossed over the canal at bridge 147 and ran to the east of Abermule when the 1975 Ordnance Survey map was published, but the Abermule western bypass had been built by 1983. To the south-west, Byles Lock and Newhouse Lock continue the ascent towards Newtown. At Aberbechan, a three-arched aqueduct carries the canal over Bechan Brook, a tributary of the River Severn. Nearby are the remains of a corn mill and some maltings. The final bridge on the watered section, no. 153, includes the cast lettering "Brymbo 1862". Immediately afterwards is Freestone Lock, beyond which the canal is dry.

Below bridge 153, water enters the canal from the Penarth Weir on the River Severn. The weir is to the south of the lock and is an unusual double-tiered structure. It was constructed by Josiah Jessop in 1813-1814 and there is a modern salmon leap on its western side. The weir can be reached from the lock by following a footpath. Between the river and the canal are the former settling beds of Dolfor Sewage Treatment Works, now maintained as a wildlife haven by the Montgomeryshire Wildlife Trust. The section of the canal from Freestone Lock to Newtown is largely filled-in and the site of the basin in Newtown, together with the last 0.5 mi of the route, has become a housing estate. A public footpath follows the route of the canal for most of the distance passing the sites of Dolfor Lock and Rock Lock on its way.

The Newtown Pumphouse raised water from the River Severn to the canal, initially using an undershot water wheel to operate two bucket pumps. This was supplemented by a steam engine for times when the waterwheel failed to provide sufficient power. In time, this arrangement was replaced by a diesel-powered pump but pumping was discontinued in the 1940s. The building, which originally had a tall chimney, still exists but is in private ownership.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Montgomery Canal


text:
Guandao

A guandao is a type of Chinese polearm that is used in some forms of Chinese martial arts. In Chinese, it is properly called a yanyuedao (偃月刀; lit. "reclining moon blade"), the name under which it always appears in texts from the Song to Qing dynasties such as the Wujing Zongyao and Huangchao Liqi Tushi. It is comparable to the Japanese naginata and the European fauchard or glaive and consists of a heavy blade with a spike at the back and sometimes also a notch at the spike's upper base that can catch an opponent's weapon. In addition, there are often irregular serrations that lead the back edge of the blade to the spike. The blade is mounted atop a 1.5 to 1.8 m long wooden or metal pole and a pointed metal counterweight used to balance the heavy blade and for striking on the opposite end.

On modern versions, a red sash or tassel is attached at the joint of the pole and blade. Variations include having rings along the length of the straight back edge as found in the nine-ring guandao, having the tip curl into a rounded spiral as in the elephant guandao, or featuring a more ornate design as exemplified by the dragon head guandao. However, apart from the "elephant guandao" none of these variations seem to have historical ground.

History
According to legend, the guandao was invented by the famous general Guan Yu during the early 3rd century AD, hence the name. It is said that he specified its form and size to be made by a smithy, and was uniquely able to wield such an imposing weapon due to his large stature and legendary strength. Guan Yu's guandao was called "Green Dragon Crescent Blade" (青龍偃月刀, Qīnglóng yǎnyuèdāo) which weighed 82 Chinese jin (estimated either at 18.26 kg or 48.38 kg, a Han dynasty jin was 222.72 g, while the jin used in the Ming dynasty—during which the Romance of the Three Kingdoms was written as 590 g).

However, while the famous novel Romance of the Three Kingdoms by Luo Guanzhong describes him as wielding the guandao, this description may have been an anachronistic one intended to make the character seem more imposing: historically speaking there was no evidence to show that Guan Yu used the weapon that is thus attributed to him, and indeed there is no indication of the existence of what is now known as the guandao prior to the 11th century, when it was first illustrated in the military manual Wujing Zongyao. The guandao, therefore, possibly did not even exist during Guan Yu's era, meaning that it could be somewhat of a pop culture-derived misnomer. Furthermore, the scholar Tao Hongjing (456-536 AD) recorded in the Gujin Daojianlu (古今刀劍錄, "A Catalogue of Ancient and Modern Sabers and Rapiers") that Guan Yu forged a pair of sabres using iron ore he harvested from Wudushan mountain (武都山) himself, which may have inspired the story that Guan Yu invented his weapon. However, this would also indicate that he did not use a guandao or even anything resembling a guandao, since the pole-mounted or long-handled dao weapons such as the pudao or dadao were all wielded with two hands and so would not have been made or used in a pair.

While some historians still contend that the guandao was simply an uncommon weapon prior to the Tang dynasty and was thus not illustrated before then, historical evidence leans towards the attribution being an instance of creative license. By the time of the Qing dynasty the guandao, for the most part, was not actually intended for field use but was instead used as a tool to test the strength of those who wished to become military officers: weapons of various weights were made, the test composed simply of performing various required maneuvers using such weapons. During the Qing dynasty some extraordinarily heavy versions of guandao were made for this purpose: a candidate had to be able to wield a weapon weighing 80, 100, or 120 jin (48 kg, 60 kg, or 72 kg, using the modern value for 1 jin = approximately 0.6 kg), with weapons of each weight being successively higher grades in the exam, the passage of which led to appointment as military officers of various ranks based on the grade. The heaviest known "testing guandao", which resides in a museum at Shanhaiguan, weighs 83 kg. While the examples are taken from the Qing dynasty and therefore may have been influenced by the book (which was written in the Ming dynasty), military officer tests (which began in the Tang dynasty) have always involved lifting heavy stones of standardized weight and maneuvering them about, possibly contributing to the writer's decision to assign an unusual weight to Guan Yu's weapon.

The weapon was also widely adopted by martial artists for the purposes of training and for demonstrating their strength, perhaps also to train specifically for the military officer's tests. Where it was used, it was largely used by infantry. In the Qing dynasty, it was used by the all Han Green Standard Army. Apart from that, the lack of standardization of the antique examples that survive to today seems to indicate that at least from the 19th century onwards it was popular in the civilian martial arts realm as well.

The modern guandao as adopted by martial artists today usually weighs between 2 and 10 kg, and is typically composed of a wood shaft of about 3 to 5 ft in length, a short blade of about 12 to 18 in on one end, and a mace head on the other (which serves mostly as a counterweight to the blade but can also be used for striking), the whole assembly rarely exceeding 5 to 6 ft in total length. The greatly reduced weight and length reflect its nature as a more practical form for martial artists.

Combat uses
The guandao is used quite frequently in the martial art of contemporary Wushu derived from the Shaolin or Wudangquan form of martial arts in modern times. According to contemporary Wushu practice, its purpose is more to disarm an opponent and deflect his strikes rather than to attack. To that end, a large veil cloth is attached to the end to dissuade and confuse opponents. However, there is no evidence of this being an authentic depiction of the weapon's historical usage. Tassels and cloths are attached to numerous weapons such as jian, dao, meteor hammer, and guandao used in Chinese opera, one of the sources of movements found in contemporary Wushu.

Forms utilizing the weapon in nearly all traditional styles of Chinese martial arts emphasize strong slashing movements and momentum to keep the heavy blade moving through a series of spinning cuts. The considerable weight of the weapon also makes guandao forms good for training the overall conditioning of the body.

Similar weapons were also used in Southeast Asia. They were famously used by royals to fight each other on elephant back.

Extremely unusual for historical weapons, the Guandao is reportedly still used today. Chinese soldiers armed with Guandaos and modern combat uniforms were photographed near the Line of Actual Control with India, where a 1996 agreement between India and China prohibits firearm usage.

Popular culture

 * In Avatar: The Last Airbender, a guandao was used by Kach, a member of the Rough Rhinos.
 * In The Legend of Korra, guandaos were used by the Chuu Brothers.
 * Power Rangers Jungle Fury features Carnisoar, the Sky Overlord with the Spirit of the Hawk, using a double-bladed guandao.
 * In the series Yona of the Dawn, the character Hak uses a guandao.
 * In the video game For Honor, the character Jiang Jun wields a guandao.
 * In the video game Warframe, the Guandao and Guandao prime are a type of polearm that you can craft.
 * Dynasty Warriors features Guan Yu wielding a guandao.
 * In the manga Kingdom, General Ouki uses as main weapon a guando, and he manages to give it to the main character Shin. There are many other references to these kinds of weapons
 * In the videogame Library of Ruina, the character Xiao wields a guandao alongside a longsword. This follows into the follow up game Limbus Company, where the character Hong Lu also wields a guandao.
 * In Honkai: Star Rail, Jing Yuan wields a guandao. He is one of the seven Arbiter-Generals of the Xianzhou Alliance's Cloud Knights, and one of the Six Charioteers of the Xianzhou Luofu.

title: Guandao


text: Category:Articulations (music)

title: Category:Articulations (music)


text:
Paraquat

Paraquat (trivial name; ), or N,N′-dimethyl-4,4′-bipyridinium dichloride (systematic name), also known as methyl viologen, is an organic compound with the chemical formula [(C6H7N)2]Cl2. It is classified as a viologen, a family of redox-active heterocycles of similar structure. This salt is one of the most widely used herbicides. It is quick-acting and non-selective, killing green plant tissue on contact. It is also toxic (lethal) to human beings and animals due to its redox activity, which produces superoxide anions. It has been linked to the development of Parkinson's disease and is banned in 58 countries.

Paraquat may be in the form of salt with chloride or other anions; quantities of the substance are sometimes expressed by cation mass alone (paraquat cation, paraquat ion).

The name is derived from the para positions of the quaternary nitrogens.

Production and redox reactions
Pyridine is coupled by treatment with sodium in ammonia followed by oxidation to give 4,4′-bipyridine. This chemical is then dimethylated with chloromethane to give the final product as the dichloride salt.

Use of other methylating agents gives the bispyridinium with alternate counterions. For example, Hugo Weidel's original synthesis used methyl iodide to produce the diiodide.

Herbicide use
Although first synthesized in 1882, paraquat's herbicidal properties were not recognized until 1955 in the Imperial Chemical Industries (ICI) laboratories at Jealott's Hill, Berkshire, England. Paraquat was first manufactured and sold by ICI in early 1962 under the trade name Gramoxone, and is today among the most commonly used herbicides.

Paraquat is classified as a non-selective contact herbicide. The key characteristics that distinguish it from other agents used in plant protection products are:

 * It kills a wide range of annual grasses and broad-leaved weeds and the tips of established perennial weeds.
 * It is very fast-acting.
 * It is rain-fast within minutes of application.
 * It is partially inactivated upon contact with soil.

These properties led to paraquat being used in the development of no-till farming.

The European Union approved the use of paraquat in 2004 but Sweden, supported by Denmark, Austria, and Finland, appealed this decision. In 2007, the court annulled the directive authorizing paraquat as an active plant protection substance stating that the 2004 decision was wrong in finding that there were no indications of neurotoxicity associated with paraquat and that the studies about the link between paraquat and Parkinson's disease should have been considered. Thus, paraquat has been banned in the European Union since 2007.

China also banned the domestic use of Paraquat in 2017, followed Thailand in 2019 and Brazil, Chile, Malaysia, Peru and Taiwan between 2020 and 2022. In the United States, paraquat is available primarily as a solution in various strengths. It is classified as a restricted use pesticide, which means that it can be used by licensed applicators only. According to an October 2021 estimate, the use of paraquat in US agriculture as mapped by the US Geological Survey showed a doubling from 2013 to 2018, reaching 10000000 lb annually.

There is an ongoing international campaign for a global ban, but the cheap and popular paraquat continues to be unrestricted in most developing countries. The Chemical Review Committee (CRC) of the Rotterdam Convention recommended to the Conference of the Parties (COP) paraquat dichloride formulations for inclusion in Annex III to the Convention in 2011. A small group of countries, including India and Guatemala and supported by manufacturers, have since blocked the listing of paraquat as a hazardous chemical for the purposes of the Rotterdam Convention.

Reactivity and mode of action
Paraquat is an oxidant that interferes with electron transfer, a process that is common to all life. Addition of one electron gives the radical cation:
 * [paraquat]2+ +  e−     [paraquat]•+

The radical cation is also susceptible to further reduction to the neutral [paraquat]0:
 * [paraquat]•+ +  e−     [paraquat]0

As an herbicide, paraquat acts by inhibiting photosynthesis. In light-exposed plants, it accepts electrons from photosystem I (more specifically ferredoxin, which is presented with electrons from PS I) and transfers them to molecular oxygen. In this manner, destructive reactive oxygen species (ROS) are produced. In forming these reactive oxygen species, the oxidized form of paraquat is regenerated, and is again available to shunt electrons from photosystem I to restart the cycle. This induces necrosis, and unlike with some mechanisms of necrosis, does not produce double-stranded breaks.

Paraquat is often used in science to catalyze the formation of ROS, more specifically, the superoxide free radical. Paraquat will undergo redox cycling in vivo, being reduced by an electron donor such as NADPH, before being oxidized by an electron receptor such as dioxygen to produce superoxide, a major ROS.

Weed resistance management
Problems with herbicide resistant weeds may be addressed by applying herbicides with different modes of action, along with cultural methods such as crop rotation, in integrated weed management (IWM) systems. Paraquat, with its distinctive mode of action, is one of few chemical options that can be used to prevent and mitigate problems with weeds that have become resistant to the very widely used non-selective herbicide glyphosate.

One example is the "double knock" system used in Australia. Before planting a crop, weeds are sprayed with glyphosate first, then followed seven to ten days later by a paraquat herbicide. Although twice as expensive as using a single glyphosate spray, the "Double Knock" system is widely relied upon by farmers as a resistance management strategy. Nevertheless, herbicide resistance has been seen for both herbicides in a vineyard in Western Australia – though this singular report gives no indication of what regimen was being followed, particularly if the two herbicides were being used in a "double knock" tandem.

A computer simulation reported in the scientific journal Weed Research showed that with alternating annual use between glyphosate and paraquat, only one field in five would be expected to have glyphosate-resistant annual ryegrass (Lolium rigidum) after 30 years, compared to nearly 90% of fields sprayed only with glyphosate. A "Double Knock" regime with paraquat cleaning-up after glyphosate was predicted to keep all fields free of glyphosate resistant ryegrass for at least 30 years.

Toxicity
Paraquat is toxic to humans (Category II) by the oral route and moderately toxic (Category III) through the skin. Pure paraquat, when ingested, is highly toxic to mammals, including humans, causing severe inflammation and potentially leading to severe lung damage (e.g., irreversible pulmonary fibrosis, also known as 'paraquat lung'), acute respiratory distress syndrome (ARDS), and death. The mortality rate is estimated between 60–90%.

Paraquat is also toxic when inhaled and is in the Toxicity Category I (the highest of four levels) for acute inhalation effects. For agricultural uses, the United States Environmental Protection Agency (EPA) determined that particles used in agricultural practices (400–800 μm) are not in the respirable range. Paraquat also causes moderate to severe irritation of the eye and skin. Diluted paraquat used for spraying is less toxic; thus, the greatest risk of accidental poisoning is during mixing and loading paraquat for use.

The standard treatment for paraquat poisoning is first to remove as much as possible by pumping the stomach. Fuller's earth or activated charcoal may also improve outcomes depending on the timing. Haemodialysis, haemofiltration, haemoperfusion, or antioxidant therapy may also be suggested. Immunosuppressive therapy to reduce the inflammation is an approach suggested by some, however only low certainty evidence supports using medications such as glucocorticoids with cyclophosphamide in addition to the standard care to reduce mortality. It is also unknown if adding glucocorticoid with cyclophosphamide to the standard care has unwanted side effects such as increasing the risk of infection. Oxygen should not be administered unless SpO2 levels are below 92%, as high concentrations of oxygen intensify the toxic effects. Death may occur up to 30 days after ingestion.

Lung injury is a main feature of poisoning. Liver, heart, lung, and kidney failure can occur within several days to weeks that can lead to death up to 30 days after ingestion. Those who suffer large exposures are unlikely to survive. Chronic exposure can lead to lung damage, kidney failure, heart failure, and oesophageal strictures. The mechanism underlying paraquat's toxic damage to humans is still unknown. The severe inflammation is thought to be caused by the generation of highly reactive oxygen species and nitrite species that results in oxidative stress. The oxidative stress may result in mitochondrial toxicity and the induction of apoptosis and lipid peroxidation which may be responsible for the organ damage. It is known that the alveolar epithelial cells of the lung selectively concentrate paraquat. It has been reported that a small dose, even if removed from the stomach or spat out, can still cause death from fibrous tissue developing in the lungs, leading to asphyxiation.

Accidental deaths and suicides from paraquat ingestion are relatively common. For example, there are more than 5,000 deaths in China from paraquat poisoning every year in part leading to China's ban in 2017. Long-term exposures to paraquat would most likely cause lung and eye damage, but reproductive/fertility damage was not found by the EPA in their review.

"Paraquat pot"
During the late 1970s, a controversial program sponsored by the US government sprayed paraquat on cannabis fields in Mexico. Following Mexican efforts to eradicate marijuana and poppy fields in 1975, the United States government helped by sending helicopters and other technological assistance. Helicopters were used to spray the herbicides paraquat and 2,4-D on the fields; marijuana contaminated with these substances began to show up in US markets, leading to debate about the program.

Whether any injury came about due to the inhalation of paraquat-contaminated marijuana is uncertain. A 1995 study found that "no lung or other injury in cannabis users has ever been attributed to paraquat contamination". Also a United States Environmental Protection Agency manual states: "... toxic effects caused by this mechanism have been either very rare or nonexistent. Most paraquat that contaminates cannabis is pyrolyzed during smoking to dipyridyl, which is a product of combustion of the leaf material itself (including cannabis) and presents little toxic hazard."

In a study by Imperial Chemical Industries, rats that inhaled paraquat showed development of squamous metaplasia in their respiratory tracts after a couple of weeks. This study was included in a report given to the State Department by the Mitre Corporation. The U.S. Public Health Service stated that "this study should not be used to calculate the safe inhalation dose of paraquat in humans."

Use in suicide and murder
A large majority (93 percent) of fatalities from paraquat poisoning are suicides, which occur mostly in developing countries. For instance, in Samoa from 1979 to 2001, 70 percent of suicides were by paraquat poisoning. Trinidad and Tobago is particularly well known for its incidence of suicides involving the use of Gramoxone (commercial name of paraquat). In southern Trinidad, particularly in Penal, Debe from 1996 to 1997, 76 percent of suicides were by paraquat, 96 percent of which involved the over-consumption of alcohol such as rum. Fashion celebrity Isabella Blow committed suicide using paraquat in 2007. Paraquat is widely used as a suicide agent in developing countries because it is widely available at low cost. Further, the toxic dose is low (10 mL or 2 teaspoons is enough to kill). Campaigns exist to control or even ban paraquat, and there are moves to restrict its availability by requiring user education and the locking up of paraquat stores. When a 2011 South Korean law completely banned paraquat in the country, death by pesticide plummeted 46%, contributing to the decrease of the overall suicide rate.

The indiscriminate paraquat murders, which occurred in Japan in 1985, were carried out using paraquat as a poison. Paraquat was used in the UK in 1981 by a woman who poisoned her husband. American serial killer Steven David Catlin killed two of his wives and his adoptive mother with paraquat between 1976 and 1984.

Parkinson's disease
According to the WHO (2022), some of the measures to prevent Parkinson's disease include "banning of pesticides (e.g., paraquat and chlorpyrifos) and chemicals (e.g., trichloroethylene) which have been linked to PD and develop safer alternatives as per WHO guidance" and "accelerate action to reduce levels of and exposure to air pollution, an important risk factor for PD". A 2011 study showed a link between paraquat use and Parkinson's disease in farm workers. A co-author of the paper said that paraquat increases production of certain oxygen derivatives that may harm cellular structures, and that people who used paraquat, or other pesticides with a similar mechanism of action, were more likely to develop Parkinson's. A 2013 meta-analysis published in Neurology found that "exposure to paraquat ... was associated with about a 2-fold increase in risk" of Parkinson's disease. A review in 2021 concluded that the available evidence does not support a causal conclusion. In 2022 and 2023, two reviews from India "decisively demonstrated that paraquat is a substantial stimulant of oxidative stress, … and is associated with Parkinson's disease (PD)"; and stated that "From the studies we can consider that PQ and MB with its combined effects has tremendous contribution towards neurodegeneration in PD."

In the UK, the use of paraquat was banned in 2007, but the manufacture and export of the herbicide is still permitted. In April of 2022, the BBC reported that some UK farmers had called for a ban on British production of paraquat, and stated that "There is no scientific consensus and many conflicting studies on any possible association between Paraquat and Parkinson's". In the US, a class action lawsuit against Syngenta is ongoing; the company rejects the claims but has paid £187.5 million into a settlement fund. As of November 2023, more than 4,000 cases against Syngenta (manufacturer of Gramoxone) and Chevron (the former distributor) are pending in the paraquat multidistrict litigation in the US; the first trial will start in 2024. In 2023, a contributor to The Guardian alleged that internal documents from the case "show Syngenta and Chevron management have known about possible risks associated with paraquat for decades ... Syngenta, with one internal memo in 1985 noting that they depended on it [paraquat] as a 'major product' and 'would do whatever possible to defend it'" and "They talk about developing scientific studies that they can use ... They talk about influencing strategies with regulators." On the contrary, Syngenta "claims it is being targeted by what it calls a 'mass tort machine' of plaintiffs' lawyers".

According to the NIEHS, pesticide exposure has consistently been associated with the onset of Parkinson's disease. Some people are more vulnerable to the harmful effects of pesticides because of their age or genetic makeup. Further research into links between preventable exposures and Parkinson's disease, as well as preventative therapies, could help reduce the incidence of the disease. For example, using protective gloves and other hygiene practices reduced the risk of Parkinson's disease among farmers using paraquat, permethrin, and trifluralin.
 * A 17-year long, NIEHS-funded study of the links between Parkinson's disease, environment, and genes shows that some pesticides, including paraquat, maneb, ziram, benomyl, and several organophosphate pesticides, including diazinon and chlorpyrifos, contribute to Parkinson's disease onset and progression.
 * People with Parkinson's disease who are exposed to a high level of ten different active ingredients in agricultural pesticides may see their motor and non-motor symptoms progress faster compared with those who are not, a 2022 study found.
 * Other NIEHS research found that people who occupationally used two pesticides, rotenone or paraquat, developed Parkinson's disease 2.5 times more often than non-users.
 * In addition, people exposed to pesticides in the home or garden may face a greater chance of developing Parkinson's disease.
 * Pesticides may directly or indirectly disrupt the biological pathways that normally protect dopaminergic neurons, the brain cells selectively attacked by the disease.
 * Some pesticides, like rotenone, can directly block the function of mitochondria, the structures that create energy to run the cell. NIEHS researchers showed in mice that disrupting mitochondria through exposure to rotenone early in development changed the epigenome—the chemical tags that turn genes on and off—in ways that persisted throughout life.
 * Other pesticides, like paraquat, have been found to increase production of free radicals that can damage cells.
 * Many studies identified genetic variations that provide insight into why certain people appear to be at higher risk of developing Parkinson's.
 * Using data from a NIEHS-conducted agricultural health study, researchers found that Parkinson's risk from paraquat use was particularly high in people with a particular variant of a gene known as GSTT1.
 * Similarly, other research has indicated that people with lower levels of the PON1 gene, which is important for the metabolism of organophosphate pesticides, showed faster progression of the disease.

title: Paraquat


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title: User talk:217.20.171.53


text: User talk:62.165.128.200

title: User talk:62.165.128.200


text: User talk:66.241.140.2

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Friday Night Lights (film)

Friday Night Lights is a 2004 American sports drama film co-written and directed by Peter Berg. The film follows the coach and players of a high school football team in the Texas city of Odessa. The book on which it is based, Friday Night Lights: A Town, a Team, and a Dream (1990) by H. G. Bissinger, followed the story of the 1988 Permian High School Panthers football team as they made a run towards the state championship. A television series of the same name premiered on October 3, 2006, on NBC. The film won the Best Sports Movie ESPY Award and was ranked number 37 on Entertainment Weekly list of the Best High School Movies.

Plot
As preseason practice begins for the Permian High School football team in August 1988, the town of Odessa, Texas has high expectations for the players and their coach Gary Gaines to win a state championship with their star running back James "Boobie" Miles. The quarterback, Mike Winchell, runs under the expectation of handing off the ball to Miles on most plays. Fullback Don Billingsley struggles with his ball handling and is abused by his alcoholic father Charles, who won a state championship with Permian. The players frequently party as they deal with the pressures of Odessa's expectations.

In the season opener against the Marshall Bulldogs, the Permian Panthers make the game a blowout. Gaines intends to bench Miles in the waning minutes, but keeps him in after third-stringer Chris Comer misplaces his helmet making him unprepared to go in. Miles is sent in but tears his ACL after being tackled at the knee on the ensuing play. After the incident, Gaines endures intense public backlash from the town for keeping Miles in. In the next game during the start of district play, Permian gets blown out as Winchell struggles with consistency in his increased role. However, after the Panthers fall behind by 14 in the next game, Comer comes into the game after the second-string running back gets injured and helps Winchell and Billingsley get Permian's offense rolling again, leading them to a comeback win. Despite their small size, Permian's defense proves to be stout under the leadership of safety Brian Chavez and linebacker Ivory Christian, and the Panthers embark on a five-game winning streak.

Miles holds out hope that he can return to playing soon. Unfortunately, his MRI scan shows that he needs immediate knee surgery and cannot play for the rest of the season. Miles boldly denies the severity of his knee injury and lies to Gaines so he can suit up again, with his uncle and legal Guardian L.V. advocating for him. Permian plays its final district game against Midland Lee, with first place and a playoff berth on the line. The Panthers fall behind, and Gaines puts Miles in out of desperation, but Miles is soon injured again. Winchell leads a comeback drive, but Permian ultimately loses as his final pass flies over the receiver's hands. After the game, Billingsley fights with his drunk father, who throws his state championship ring onto the side of the freeway. The next morning, Don reveals to his father that he recovered the championship ring and gives it back to him. Charles partially apologizes and makes the point that his state championship was the best thing that happened to him, and he now has nothing happy except those memories. The loss puts Permian in a three-way tie for first place with Lee and Abilene Cooper, and a coin toss is held to determine which two teams make the playoffs. Permian and Lee win the toss, and as the Panthers prepare for the playoffs, Miles clears his locker. While in his uncle's car, he cries about his future being bleak now that his promising football career has ended.

Permian is successful in the playoffs, but all eyes are on the state powerhouse Dallas Carter High School. Permian and Carter make it to the state championship game, which is held at the Astrodome. Miles rejoins the team and watches from the sidelines as the Panthers head into the game. They are initially overwhelmed by Carter's superior size and fall behind, although an interception by Christian helps get them on the board before halftime. In the second half, Carter gains a 20-point lead after a pass on fourth down which hit the turf is erroneously ruled complete. However, Permian's defense improves its tackling and the offense pushes through despite injuries as the Panthers score 14 unanswered points to cut the deficit to six. They stop Carter on fourth and inches, leaving the offense to go 75 yards in less than two minutes for the win. Winchell, Billingsley, and Comer are all injured, but the former two reenter the game. Billingsley takes the ball to the 1-yard line on fourth down, but the play is called back due to a holding penalty. With two seconds left, Winchell desperately runs the ball toward the goal line but is stopped just short, and Carter wins the championship. As the Permian players soak in their defeat, Billingsley reconciles with his father.

Afterwards, Gaines removes the outgoing seniors from his depth chart, and it is revealed that Winchell, Billingsley, Miles, and Chavez went on to have successful lives after their football careers ended, with only Christian earning a Division I scholarship. The film ends with the statement that Gaines and Comer led Permian to an undefeated state championship season the following year.

Cast

 * Billy Bob Thornton as Coach Gary Gaines
 * Derek Luke as James "Boobie" Miles
 * Jay Hernandez as Brian Chávez
 * Lucas Black as Michael "Mike" Winchell
 * Garrett Hedlund as Donald "Donny" Billingsley
 * Tim McGraw as Charles Billingsley
 * Connie Britton as Sharon Gaines
 * Lee Thompson Young as Christopher "Chris" Comer
 * Lee Jackson as Ivory Christian
 * Julius Tennon as Coach Freddie James
 * Connie Cooper as Ms. Winchell
 * Amber Heard as Maria
 * Stephen Bishop as Loie Harris
 * Christian Kane as Brian
 * Brad Leland as John Aubrey
 * Bryan Gutierrez as Midland Lee Trainer

Cameos

 * Former NFL wide receiver Roy Williams (a Permian alumnus) had a cameo in the film as an assistant coach for Midland Lee, Permian's arch-rival.
 * Some sequences during the state playoffs showed highlights from high school football games in Texas. In one of those highlights, NFL Pro Bowl cornerback Aqib Talib can be seen.
 * Ty Law played a wide receiver for Dallas Carter, the team Permian played in the film's state championship game. He wore jersey #2, his last name was Graf, and he caught a one-handed touchdown pass.
 * The real James "Boobie" Miles played a Permian assistant coach in the film. Although he has no lines, he was seen several times. In the locker room scene at halftime of the state championship game, he was seen standing next to the fictional "Boobie" Miles as Coach Gaines gives his speech.

Players

 * In the film, Boobie Miles was depicted as one of the team's three captains, but that honor was held by Ivory Christian, Mike Winchell, and Brian Chavez in real life.
 * In the film, some of the players' numbers and positions were changed: Boobie Miles was #45 and played tailback in the film but in the book he was playing fullback (while Don Billingsley was the tailback) and #35. In the film, Brian Chavez was the #4 strong safety, while he was the #85 tight end in the book, and Ivory Christian was a defensive end and wore #90, while he was the #62 middle ("Mike") linebacker in the book. At the beginning of the film, as the camera panned over Coach Gaines' depth chart, 'Miles' name was listed under the FB tag. Chris Comer was also the backup fullback in the book, not a third-string tailback. One of the athletic directors in the stadium booth said, "I think he's a sophomore", when Comer was a junior at the time. Comer also wore #45 in the real season, but in the film, he wore #42. Alan Wyles was depicted as a wide receiver when he was the placekicker.
 * Don Billingsley's father Charlie was depicted in the film as having won a state championship. In reality, as a junior, the 1968 Permian team lost in the finals.

The regular season
In the film, the team was depicted as practicing in full pads and with full contact on the first day of practice. Under rules of the University Interscholastic League (UIL), the governing body for Texas public school sports, teams cannot use pads or hit until the fourth day of practice (however, in the deleted scenes included in the DVD, a non-pad practice was shown).
 * A Permian booster was heard toasting Coach Gaines' second season as Permian's head coach. It was his third.
 * Boobie Miles, in the book, injured his knee by getting his foot caught on the AstroTurf during a pre-season scrimmage against Amarillo Palo Duro at Jones Stadium in Lubbock. In the film, he was tackled by two players at the knee during a blowout regular season non-district game at Ratliff Stadium.
 * In the film, the top-ranked Permian Panthers defeated the hapless Marshall Bulldogs in a non-district game. In real life, the third-ranked Marshall Mavericks (whose colors are red and white, not purple and gold) defeated fourth-ranked Permian 13–12. In the film, the game was the season opener and played on a Friday night in Odessa. In real life, it was Permian's second game of the season and played at Maverick Stadium in Marshall on a Saturday afternoon. Permian's football team chartered a jet for the 500+ mile trip from Odessa to Marshall, spawning controversy on the cost of the trip. Played before a crowd of more than 12,000 fans at Maverick Stadium, the game was on a searing September afternoon when the temperature topped 100 degrees Fahrenheit (38 °C). The footage shown in the film was from a game against the Midland High Bulldogs, who weren't mentioned in the film. Permian defeated the Dawgs 42–0 in district play, but the two teams ended up in a three-way tie along with Midland Lee for the district title.
 * In the film, district play began in week 2. In the real regular season, district play began in week 4.
 * In the film, Permian defeated "North Shore Galena" in a mid-season (presumably district) game. In reality, North Shore High School was within the Galena Park Independent School District located in the Houston suburbs over 500 miles (800 km) southeast of Odessa. Although North Shore and Permian have both been 5A football powerhouses, they have never played. Furthermore, North Shore did not start seeing football success until the mid-1990s.
 * In reality, the three teams tied for best district record were Permian, Midland Lee, and Midland High, all with 5-1 district records. In the film, Permian and Lee were joined not by Midland but by Abilene Cooper, and each team had two district losses. The tie-breaking coin flip was held at a truck stop outside of Midland, and Midland High lost (Cooper in the film), so Permian and Lee went on. Midland High's missing the playoffs was poignant as it had not been to the playoffs since 1951 and did not get back to post-season play until 2002.
 * A Permian player (Mike Winchell) was shown with coach Gaines at the coin toss. In reality, no players from any of the three schools were allowed at the coin toss. All of Permian's players were on the team bus returning from the game that evening at San Angelo Central. Permian assistant coach Mike Belew drove with Gaines from San Angelo to the site of the coin toss.
 * In a few scenes, players were shown wearing Under Armour apparel and facemask shields, although in 1988, Under Armour and visors hadn't been invented yet. (Under Armour founder Kevin Plank was in high school in 1988.) The book says they wore green visors, which are now outlawed for high school and college teams.
 * In the film, the quarterback for Midland Lee was shown wearing a Riddell Revolution-style football helmet. The brand, Riddell, had been around since 1929, but the design didn't appear until 2002.
 * In the film, the annual duel against Permian's archrival Midland Lee was portrayed as Lee having a handy lead throughout the game, with Permian never having a shot at victory. In real life, Lee had to come from behind with a late-game touchdown to win the game 22–21.

The playoffs

 * Permian's first opponent in the playoffs was Amarillo Tascosa and not Dallas Jesuit as in the film. In 1988, Texas Public Schools (such as Permian, Carter, and Tascosa) and private schools (such as Jesuit) competed in separate leagues with separate playoffs. Jesuit was not allowed to join the previously all-public school UIL until 2003, starting football competition in 2004. Dallas Jesuit and Strake Jesuit of Houston were the only private schools who currently play in the UIL, the rest competing in leagues such as TAPPS and the SPC. Also, with the district set up at that time, it would have been impossible for Permian to play a team from the Dallas/Fort Worth Metroplex until the third round of the playoffs. Nowadays, Permian could play Fort Worth-area teams in the first round of the playoffs, but still could not play Jesuit until round 3. Permian played Dallas Jesuit in Odessa during the regular season in 1988, winning 48–2. Jesuit's only points came on a missed-PAT return, which was a rule instituted that year (the defensive conversion was not allowed in high school football under National Federation of State High School Associations rules, but Texas plays by NCAA rules). Jesuit's helmet was shown as white and orange with a sort of wildcat's head logo on it, but in real life, they are solid gold without a logo.
 * In the film, it was said that Carter was the state's top-ranked team when Carter was never ranked higher than No. 3 in the Associated Press poll.
 * Carter played "Hays" High School in the playoffs, which was depicted as wearing green and white and nicknamed the Rams. The real Jack C. Hays High School, located 15 minutes south of Austin in Buda, used red, white, and blue as its colors, and their nickname was the Rebels. Hays was a Class 4A school in 1988 and did not become 5A until 2000. Hays was in the film because the makers filmed crowd shots at Hays High during a Rebels home game against the Austin Westlake Chaparrals, another team depicted as a Permian playoff victim.
 * Permian was depicted as playing "San Angelo" in the quarterfinal round. There were two high schools in the San Angelo Independent School District; until 1998, San Angelo Central High School, the district's only 5A school had been in the same district as Permian (having since been transferred, for football only, to the district with Lubbock and Amarillo schools), and could only have played Permian in the quarterfinal round (owing to the structure of UIL playoffs) if they had qualified. However, Central finished 5th in the district that year, and as only two teams from each district qualified in 1988, Permian and Central did not play in the 1988 playoffs. Instead, Permian played Arlington Lamar in the quarterfinals.
 * On the playoff brackets it shows just the word "Baytown". There were two high schools in Baytown in 1988 (there are now three), the team in the playoffs was Baytown Lee.

Permian vs. Carter

 * Since 1982, the UIL Class 5A (now 6A) football playoffs have had six rounds (though a second, parallel playoff bracket of five rounds was added in 1990, later also expanded to six rounds in 2006), so while Permian played Dallas Carter in the fifth round, it was a semi-final and not a final. In the Texas playoffs, a team from North or Western Texas always plays a team from the Houston area or Southern Texas in the final, so the Carter vs Permian final was not possible. The real-life final featured Carter versus Converse Judson (which defeated Permian in the 1995 state championship). The Carter-Permian game was played in front of 10,000 people in a heavy downpour at The University of Texas at Austin's Memorial Stadium, not in front of 55,000 in the Astrodome in Houston. While the game in the film was a high-scoring affair (34-28), the real score was 14–9 in favor of Carter. In real life, Permian held a 9–7 lead for most of the game and Carter made the dramatic fourth-quarter comeback to win. On the last play of the game, Winchell threw the ball incomplete, rather than running it himself close to the goal line.
 * The meeting between officials from Permian and Carter at the Midland airport occurred the Sunday prior to the game. Not shown in the film was the Carter officials changing their minds about a home site from Texas Stadium in Irving to the Cotton Bowl within the Dallas city limits. Under UIL rules, if the schools cannot agree to a neutral site, each side picks a "home" site and a "neutral" site, and two coin tosses are conducted. The first was to determine whether a "home" or "neutral" site would be used, and the second was to determine which team's site will be used. After a tense battle between the sides, they agreed to play the game at Austin.
 * In the film, Gaines at first suggests San Antonio as a potential neutral site, which would have meant playing the game at Alamo Stadium, since the Alamodome did not open until 1993. The other neutral site suggestion in the film was College Station, presumably meaning Kyle Field at Texas A&M.
 * The revocation of Carter's state championship following their use of an academically ineligible player was never mentioned, nor was the prolonged legal battle that Carter went through to enable them to play in the playoffs. Officially, the 1988 state champions were Converse Judson, which lost 31–14 in the final to Carter.

The school and the city

 * Permian was portrayed in the film as a single large high school in a small, one-horse town in West Texas. In reality, Odessa was a city of nearly 100,000 people at the time of the events portrayed in the film, and part of a metropolitan area of nearly 250,000 combining the populations of Midland and Ector counties. (The quaint downtown shown in the trailer for the film was Manhattan, Kansas.) Also, Permian was (and still is) only one of two large Class 5A high schools in Odessa. The other and first high school in the city, Odessa High School (mascot: the Bronchos), was never mentioned in the film, despite the fact that they have played Permian every year, as the two schools have been in the same UIL district since Permian opened in 1959 and shared Ratliff Stadium with Permian. An entire chapter in the book was devoted to the "Civil War" between the schools.
 * In the film, Odessa was portrayed as being a mostly Anglo town with a sizable African-American population and virtually no Hispanics. In 1988, out of the almost 100,000 people that lived in Odessa, one-third were Hispanic while African-Americans made up only 5% of the population.
 * Ratliff Stadium was depicted as the location for Permian football practices. In reality, the team practiced mostly on campus, and the stadium, used by both Permian and Odessa, was on the outskirts of town in a fairly unpopulated area about three miles (five km) away from the Permian High campus. It was also unlikely that children would be playing touch football near the stadium, as depicted in the film, as few houses were nearby at that time. The area around the stadium has grown dramatically since then (which caused an anachronism in the film—the houses seen near the stadium did not yet exist in 1988).
 * While Ratliff Stadium has had artificial turf since its opening, in 1988 it had the original AstroTurf, not the modern FieldTurf surface seen on the stadium in the film.

Soundtrack
The soundtrack for the film predominantly featured post-rock band Explosions in the Sky. Music by Daniel Lanois and rock band Bad Company were also included. Other songs in the film were "Just Got Paid" by ZZ Top during the montage of the Panthers' road to the finals; the pump-up song featured as the team ran through the tunnel in the game against Dallas Carter was "New Noise" by the seminal Swedish punk band Refused. During the start of the third quarter during the Championship game, the song "I Wanna Be Your Dog" by The Stooges was used. Three songs from Public Enemy's album It Takes a Nation of Millions to Hold Us Back were also used prominently.

Critical reception
On Rotten Tomatoes, the film has an approval rating of 82% based on 173 reviews, with an average rating of 7.10/10. The consensus reads: "An acute survey of the football-obsessed heartland that succeeds as both a stirring drama and a rousing sports movie." The film also has a score of 70/100 on Metacritic, based on 35 reviews.

Film critic Roger Ebert awarded the film 3 and ½ stars, writing, "The movie demonstrates the power of sports to involve us; we don't live in Odessa and are watching a game played 16 years ago, and we get all wound up."

Other reviews opined the film seemed to glorify what it was criticizing. Charles Taylor of Salon wrote, “...in the second half, the movie turns into a rah-rah celebration of exactly the mindset it's spent the first half criticizing. All of the bad things that have resulted from the characters' mindless devotion to gridiron glory--the abusive father who stays drunk to forget that the peak of his life came at 17; the barely educated Boobie's having nothing left in his life when a knee injury ends his dream of playing pro -- are converted into obstacles that test the mettle of the young warriors”. Taylor did praise the acting, particularly the performances of Black, Luke, and Thornton.

Earl Ofari Hutchinson of the Los Angeles Times criticized the film for skirting the issue of race relations in Odessa, which Bissinger had gone in depth about in his book. Peter Travers of Rolling Stone awarded the film 3 stars but said it did not sufficiently get into the heads of the players like the book did.

While the residents of Odessa held a negative reception of the book due to its account of race relations in the Texas city, they eagerly anticipated the release of the film.

Accolades
The film was recognized by American Film Institute in these lists:
 * 2004: AFI's Top 10 Film of the Year
 * 2008: AFI's 10 Top 10:
 * Nominated Sports Film

title: Friday Night Lights (film)