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Category talk:Neurotoxins

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A lot of the stuff I've been adding to the neurotoxins category is pretty disputable depending on what your definition is. My goal was to be as inclusive as possible, so basically anything that modulated ion channels, postsynaptic receptors, synaptic vessicles, etc. I would also be inclined to include most teratogens.

I think the neuroscientist's definition of a neurotoxin is probably different from that of a clinician. For a neuroscientist there's a lot of overlap between the concept of any neuromodulatory experimental tool and the concept of a neurotoxin. To me, anything nonphysiological (i.e. exogenous) that acts on channels, receptors, or synaptic vessicles, whether in vitro, in vivo, or in development, pretty much counts. My thinking was also that if the definition of the category is different for different people, better to go for the most inclusive definition.

I've already been opposed on a few of my additions. I'd appreciate more people's thoughts on what they think is appropriate for the category. I wouldn't be opposed to directing my efforts to a different category like "Neuromodulators", but in that case I want to nail down what's okay for this category first. --Chinasaur 01:46, 11 Aug 2004 (UTC)

I would dispute some of the items in this catagory, where is the evidence that opioid antagonists are neurotoxic for instance? From a quick PubMed search it seems that they can be neuroprotective in some situations and worsen neurodegeneration in others, but i find no evidence that they cause any neurotoxicity by themselves without the influence of other causative factors. Classing them as neurotoxins is misleading and will only concern patients who take these drugs (for the treatment of alcoholism or gambling addiction for instance) Meodipt 02:37, 18 February 2007 (UTC)

title: Category talk:Neurotoxins


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Talk:Neurotoxin

Category talk:Neurotoxins
Please see my discussion on the Category talk:Neurotoxins page. --Chinasaur 01:47, 11 August 2004 (UTC)

Merge
why isn't neurotoxin and neurotoxicity the same article. I have no say in whether they are combined or not, but it seens they are kind of the same. jess523s
 * Disagree- They are two different things.--Super7am 23:32, 25 August 2006 (UTC)
 * Agree - neurotoxic (neurotoxicity) should be fused into this article. Poisonous redirects to poison. It would also create one complete article since the information now is minimal. --Surreal 13:51, 11 January 2006 (UTC)
 * Agree - They are both too similar to merit seperate articles. Just for the record, everyone has an equal say in matters such as this mastodon 22:40, 7 May 2006 (UTC)
 * Agree-Each of these articles are too small as it is, and merging them would create a more comprehensive article. --Kahlfin 19:25, 8 May 2006 (UTC)
 * Agree- These articles need some expansion to be worthwhile - it would be better just to consolidate them into the same one. Gkeeling 20:03, 25 May 2006 (UTC)
 * Disagree The concepts are related, but distinct--neurotoxins certainly cause neurotoxicity, but not all neurotoxicity is a result of the actions of neurotoxins. For example, abnormally high levels of endogenous neurotransmitters can have a neurotoxic effect, or metabolic disorders that cause hypoxia...I'm very busy right now, but I can try to expand these articles in the next week or two. -- Scientizzle 18:41, 15 June 2006 (UTC)
 * Disagree I concur with the previous statement. When I think of neurotoxicity, I see a separate and expansive realm of science involving endogenous factors such as excitotoxicity that in some circumstances may be caused by a neurotoxin but are certainly not exlusive to neurotoxins. Oligodendrocyte 16:22, 7 July 2006 (UTC)
 * Weak Agree - I disagree with the above statement on the grounds of common material. Besides the issue of excitotoxicity and other endogenous factors, it seems like most material appearing in one of the articles would appear in the other. Perhaps neurotoxin should be a section within neurotoxicity.Leon... 07:06, 9 July 2006 (UTC)
 * Agree - The two articles are similar it many respects and the merger would improve the quality of both as neurotoxicity can easily be sen as an aspect of neurotoxins
 * Disagree If accurate, these should be two distinct categories, neurotoxin referring to a compound that causes an (adverse) effect, neurotoxicity refering to the principles and mechanisms of action of such compounds. Thomas
 * DisagreeThey are two different things.Biophys 04:54, 20 January 2007 (UTC)
 * DISAGREEthey are different words so they have diferent words they shouldnt be combined. —The preceding unsigned comment was added by 71.153.170.194 (talk • contribs).

The merge proposal tag was removed today for no consensus. -- Scientizzle 03:06, 26 February 2007 (UTC)

A "toxin" != a poison.
I don't know whether the term "toxin" in english toxicology can be applied to all kinds of poisons; in german toxicology, for instance, "toxin" reffers only to a biogenic (i.e. produced by an organism) poison. It is not correct to label e.g. neurotoxic heavy metals or organophosphates as "neurotoxins", since they are of mineral or synthetic origin. A typical neurotoxin is tetrodotoxin or strychnine, but not lead, mercury or Sarin. Could some english-native-speaking toxicologist clarify, whether it is right to mark all neurotoxic substances as "neurotoxins", please?--84.163.95.165 18:26, 21 March 2007 (UTC)

 * The article on toxins is stating the same, along with mention, that the term "toxin" is generously used by general public, or media as a synonyme to all toxic substances or even toxicity as such. I see the problem, that for non-professionals, the term "toxin" is completely interchangeable with "poison", and many articles on synthetic neurotoxic poisons are describing them as "neurotoxins" (example: Tetramethylenedisulfotetramine, a synthetic condensation product of sulfamide and methanal, which is a potent convulsant), but I think that it would be appropriate to reformulate following part of this article:

"Toxins ingested from the environment are described as exogenous and include gases (such as carbon monoxide), metals (such as mercury), liquids (ethanol) and an endless list of solids. When exogenous toxins are ingested, the effect on neurons is largely dependent on dosage. Thus, ethanol (alcohol) is inebriating in low doses, only producing mild neurotoxicity. Prolonged exposure to "safe" alcohol levels slowly weakens and kills neurons."

and (maybe, with the exception of ethanol, as it can be of biogenic origin) to distinguish them from proper neurotoxins, which are discussed in the rest of the article.

Parallelly, an article dealing with neurotoxic substances should be created, or incorporated into the main article Poison, same goes for haemotoxic, cardiotoxic, cytotoxic and otherwise poisonous compounds. A lot of work, yes, but Wiki should be an encyclopedia...--84.163.109.68 23:10, 22 March 2007 (UTC)

some sources on this question
Hello. There is a book about neurotoxins, which says in preface: "Neurotoxins are toxic substances with selective actions on the nervous system. By definition, toxins are of natural origin, but the term 'neurotoxin' has been widely applied to some synthetic chemicals that act selectively on neurones" `a5b (talk) 23:49, 25 May 2011 (UTC)

Portal
Anytime I see neurotoxin, I read it in GLaDOS's voice. — Preceding unsigned comment added by 96.24.179.52 (talk) 19:11, 16 July 2011 (UTC)

Agreed Try searching it and go to images CodyM2001 (talk) 05:19, 25 April 2014 (UTC)

Some Updates
I have made significant changes to the Neurotoxin article. I am relatively new to the process of editing Wikipedia articles and not sure about the policy of replacing existing material. I believe what I have written to be significantly improved over the existing article and so will be uploading it shortly for people to look at. I know the history function exists so nothing from the past will be deleted. In what I have written there are a few problems of which I am aware:

1) The clostridium tetani image is not linking properly (maybe because it is not in the english language section of wikipedia, I have no idea).

2) Some of my links to other articles are not working properly while the majority seem to work fine, and I am not sure what the problem is.

3) Additionally, when I uploaded what I had written, links to neurotoxin articles in other languages disappeared for some reason.

4) Lastly, my references are not in Wikipedia's preferred format, because I was unable to get it working. Hopefully everything is cited well enough that the article can be changed easily to the preferred format. I will work on this improvement as well in the near future.

I hope that this upload is appreciated, and I apologize in advance if this breaks any Wikipedia rules of which I am not aware.

--Rysin (talk) 14:22, 9 December 2011 (UTC)

File:Clostridium tetani bacteria.jpg Nominated for speedy Deletion

 * I'm not sure why this image got tagged. Anybody know how to fix the problem. I really like this image, and think it would be useful in the article. If it helps, I found the image under the Greek language 'Tetanus' Wikipedia article. This is the direct link to the file: Clostridium Botulinum I believe the file is in the public domain as it says, and should thus not be a problem. Hopefully somebody knows how to fix this. --Rysin (talk) 01:53, 16 December 2011 (UTC)

 * Hi Rysin, and congratulations on the excellent work you have done on this article. This image was not displaying originally because it was available on the Greek Wikipedia only. I uploaded it to the English Wikipedia (mistakenly, since the software inconveniently steered it onto the English Wikipedia when I thought I was uploading to WikiCommons). Anyway, that is why the image started displaying on the article. Now a bot is playing games, as you can see from my reply on the talk page of the image. If it mindlessly deletes the image, we'll just have have another go. --Epipelagic (talk) 03:53, 16 December 2011 (UTC)

 * Hey Epipelagic, thanks and that sounds good hopefully it will work. Also I like what you wrote for anatoxin-a, I changed the title of that section hopefully to be a little more fitting. --Rysin (talk) 13:19, 16 December 2011 (UTC)

 * Well another bot went ahead anyway and summarily removed the image. The system for loading images on Wikipedia seems very dysfunctional. Anyway, when I get time, I'll try loading the image to commons, or you could have a go yourself :) --Epipelagic (talk) 01:40, 17 December 2011 (UTC)

 * It turns out an admin summarily removed the image, and he refuses to discuss the matter. So welcome to Wikipedia. Its a fascinating mixture of the sublime and the abysmal. It definitely helps if you happen to be a saint. Anyway, Commons are helpful, and it seems the image can be uploaded there :) --Epipelagic (talk) 02:32, 18 December 2011 (UTC)

25i-NBOMe and Rutgrere 2012 - publication nowhere to be found?
The alleged citation for 25i-NBOMe's neurotoxicity - Rutgrere 2012 - doesn't seem to exist?

Thoughts? — Preceding unsigned comment added by 24.121.115.108 (talk) 05:47, 23 October 2014 (UTC)

External links modified (February 2018)
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Audience Analysis
This excellent article appears to be addressed mainly to chemists and perhaps environmental scientists. A much larger audience that is not yet addressed consists of people who simply don't want their brains poisoned and who may also want to protect the unusually vulnerable brains of their children, including especially fetuses and infants. I wish I had time to be more constructive, but here are a few lay articles suggestive of what I would include: OOPS! I accidentally deleted most of the suggestions. Stay tuned. Page Notes (talk) 01:51, 2 November 2019 (UTC)

Neurotoxins
Neurotoxins are toxins that are destructive to nerve tissue (causing neurotoxicity).[3] Neurotoxins are an extensive class of exogenous chemical neurological insults[4] that can adversely affect function in both developing and mature nervous tissue.[5] The term can also be used to classify endogenous compounds, which, when abnormally contacted, can prove neurologically toxic.[4] Though neurotoxins are often neurologically destructive, their ability to specifically target neural components is important in the study of nervous systems.[6] Common examples of neurotoxins include lead,[7] ethanol (drinking alcohol),[8] glutamate,[9] nitric oxide,[10] botulinum toxin (e.g. Botox),[11] tetanus toxin,[12] and tetrodotoxin.[6] Some substances such as nitric oxide and glutamate are in fact essential for proper function of the body and only exert neurotoxic effects at excessive concentrations. 2409:4063:4E8D:58C2:0:0:AA48:7506 (talk) 16:45, 5 May 2022 (UTC)

Neurotoxins
Neurotoxins are toxins that are destructive to nerve tissue (causing neurotoxicity).[3] Neurotoxins are an extensive class of exogenous chemical neurological insults[4] that can adversely affect function in both developing and mature nervous tissue.[5] The term can also be used to classify endogenous compounds, which, when abnormally contacted, can prove neurologically toxic.[4] Though neurotoxins are often neurologically destructive, their ability to specifically target neural components is important in the study of nervous systems.[6] Common examples of neurotoxins include lead,[7] ethanol (drinking alcohol),[8] glutamate,[9] nitric oxide,[10] botulinum toxin (e.g. Botox),[11] tetanus toxin,[12] and tetrodotoxin.[6] Some substances such as nitric oxide and glutamate are in fact essential for proper function of the body and only exert neurotoxic effects at excessive concentrations. 2409:4063:4E8D:58C2:0:0:AA48:7506 (talk) 16:45, 5 May 2022 (UTC)

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

title: Talk:Neurotoxin


text:
Mexico City Metro

The Mexico City Metro (Metro de la Ciudad de México) is a rapid transit system that serves the metropolitan area of Mexico City, including some municipalities in the State of Mexico. Operated by the Sistema de Transporte Colectivo (STC), it is the second largest metro system in North America after the New York City Subway.

The inaugural STC Metro line was 12.7 km long, serving 16 stations, and opened to the public on 4 September 1969. The system has expanded since then in a series of fits and starts. , the system has 12 lines, serving 195 stations, and 226.49 km of route. Ten of the lines are rubber-tired. Instead of traditional steel wheels, they use pneumatic traction, which is quieter and rides smoother in Mexico City's unstable soils. The system survived the 1985 Mexico City earthquake.

Of the STC Metro's 195 stations, 44 serve two or more lines (correspondencias or transfer stations). Many stations are named for historical figures, places, or events in Mexican history. It has 115 underground stations (the deepest of which are 35 m below street level); 54 surface stations and 26 elevated stations. All lines operate from 5 a.m. to midnight. At the end of 2007, the Federal District government announced the construction of the most recent STC Metro line, Line 12, which was built to run approximately 26 km towards the southeastern part of the city, connecting with Lines 7, 3, 2 and 8. This line opened on 30 October 2012.

Concept of the Metro and early plans

By the second half of the twentieth century, Mexico City had serious public transport issues, with congested main roads and highways, especially in the downtown zone, where 40 percent of the daily trips in the city were concentrated. 65 of the 91 lines of bus and electric transport served this area. With four thousand units in addition to 150,000 personal automobile peak hours, the average speed was less than walking pace.

The principal promoter of the construction of the Mexico City Metro was engineer Bernardo Quintana, who was in charge of the construction company Ingenieros Civiles y Asociados (Civil Engineers and Associates). He carried out a series of studies that resulted in a draft plan which would ultimately lead to the construction of the Mexico City Metro. This plan was shown to different authorities of Mexico City but it was not made official until 29 April 1967, when the Government Gazette ("Diario Oficial de la Federación") published the presidential decree that created a public decentralized organism, the Sistema de Transporte Colectivo, with the proposal to build, operate and run an underground rapid transit network as part of Mexico City's public transport system.

The Mexico City Metro benefited from a great amount of technical assistance made available by France. RATP's engineering branch SOFRETU played a major role in its initial planning and the design of the first lines, hence the choice of tyre/rail technology.

On 19 June 1967, at the crossroads of Chapultepec Avenue with Avenida Bucareli, the inauguration ceremony for the Mexico City Metro took place. Two years later, on 4 September 1969, an orange train made the inaugural trip between Zaragoza and Insurgentes stations, thus beginning daily operation up to today.

First stage (1967–1972)
The first stage of construction comprised the construction, done by Grupo ICA, and inauguration of lines 1, 2 and 3. This stage involved engineers, geologists, mechanics, civil engineers, chemists, hydraulic and sanitation workers, electricians, archaeologists, and biologists; specialists in ventilation, statistics, computation, and in traffic and transit; accountants, economists, lawyers, workers and laborers. Between 1,200 and 4,000 specialists and 48,000 workers participated, building at least 1 km of track per month, the fastest rate of construction ever for a subway.

During this stage of construction workers uncovered two archaeological ruins, one Aztec idol, and the bones of a mammoth (on display at Talismán station).

By the end of the first stage, namely on 10 June 1972, the STC Metro had 48 stations and a total length of 41.41 km: Line 1 ran from Observatorio to Zaragoza, Line 2 from Tacuba southwest to Tasqueña and line 3 from Tlatelolco to Hospital General in the south, providing quick access to the General Hospital of Mexico.

Second stage (1977–1982)
No further progress was reached during President Luis Echeverría's government, but during José López Portillo's administration, a second stage began. The Comisión Ejecutiva del Metro (Executive Technical Commission of Mexico City Metro) was created in order to be in charge of expanding the STC Metro within the metropolitan area of Mexico City.

Works began with the expansion of Line 3 towards the north from Tlatelolco to La Raza in 1978 and to the current terminal Indios Verdes in 1979, and towards the south from Hospital General to Centro Médico in 1980 and to Zapata months later. Construction of lines 4 and 5 was begun and completed on 26 May – 30 August 1982, respectively; the former from Martín Carrera to Santa Anita and the latter from Politécnico to Pantitlán. Line 4 was the first STC Metro line built as an elevated track, owing to the lower density of big buildings.

Third stage (1983–1985), and the 1985 earthquake
This construction stage took place from the beginning of 1983 through the end of 1985. Lines 1, 2 and 3 were expanded to their current lengths, and new lines 6 and 7 were built. The length of the network was increased by 35.29 km and the number of stations to 105.

Line 3's route was expanded from Zapata station to Universidad station on 30 August 1983. Line 1 was expanded from Zaragoza to the current terminal Pantitlán, and line 2 from Tacuba to the current terminal Cuatro Caminos. These last two were both inaugurated on 22 August 1984.

Line 6's route first ran from El Rosario to Instituto del Petróleo; Line 7 was opened from Tacuba to Barranca del Muerto and runs along the foot of the Sierra de las Cruces mountain range that surrounds the Valley of Mexico at its west side, outside of the ancient lake zone. This made it possible for Line 7 to be built as a deep-bore tunnel.

On the morning of 19 September 1985, a magnitude 8.0 earthquake struck Mexico City. Many buildings as well as streets were left with major damage making transportation on the ground difficult, but the STC Metro was not damaged because a rectangular structure had been used instead of arches, making it resistant to earthquakes, thus proving to be a safe means of transportation in a time of crisis.

On the day of the quake, the Metro stopped service and completely shut down for fear of electrocution. This caused people to get out of the tunnels from wherever they were and onto the street to try to get where they were going. At the time, the Metro had 101 stations, with 32 closed to the public in the weeks after the event. On Line 1, there was no service in stations Merced, Pino Suárez, Isabel la Católica, Salto del Agua, Balderas or Cuauhtémoc. On Line 2, there was no service between stations Bellas Artes and Tasqueña. On Line 3 only Juárez and Balderas were closed. Line 4 continued to operate normally. All of the closed stations were in the historic center area, with the exception of the stations of Line 2 south of Pino Suárez. These stations were located above the ground. The reason these stations were closed was not due to damage to the Metro proper, but rather because of surface rescue work and clearing of debris.

Fourth stage (1985–1987)
Fourth stage saw the completion of Line 6 from Instituto del Petróleo to its eastern terminal Martín Carrera and Line 7 to the north from Tacuba to El Rosario. Line 9 was the only new line built during this stage. It originally ran from Pantitlán to Centro Médico, and its expansion to Tacubaya was completed on 29 August 1988. For Line 9, a circular deep-bore tunnel and an elevated track were used.

Fifth stage (1988–1994)
For the first time, a service line of the Mexico City Metro ran into the State of Mexico: planned as one of more líneas alimentadoras (feeder lines to be named by letters, instead of numbers), line A was fully operational by its first inauguration on 12 August 1991. It runs from Pantitlán to La Paz, located in the municipality of the same name. This line was built almost entirely above ground, and to reduce the cost of maintenance, steel railway tracks and overhead lines were used instead of pneumatic traction, promoting the name metro férreo (steel-rail metro) as opposed to the previous eight lines that used pneumatic traction.

The draft for Line 8 planned a correspondencia (transfer station) in Zócalo, namely the exact center of the city, but it was canceled due to possible damage to the colonial buildings and the Aztec ruins, so it was replanned and now it runs from Garibaldi, which is still downtown, to Constitución de 1917 in the southeast of the city. The construction of line 8 began in 1988 and was completed in 1994.

With this, the length of the network increased 37.1 km, adding two lines and 29 more stations, giving the metro network at that point a total of 178.1 km, 154 stations and 10 lines.

Sixth stage (1994–2000)
Assessment for line B began in late 1993. Line B was intended as a second línea alimentadora for northeastern municipalities in the State of Mexico, but, unlike line A, it used pneumatic traction. Construction of the subterranean track between Buenavista (named after the old Buenavista train station) and Garibaldi began in October 1994. Line B was opened to the public in two stages: from Buenavista to Villa de Aragón on 15 December 1999, and from Villa de Aragón to Ciudad Azteca on 30 November 2000.

Seventh stage (2008–2014)
Plans for a new STC Metro line started in 2008, although previous surveys and assessments were made as early as 2000. Line 12's first service stage was planned for completion in late 2009 with the creation of track connecting Axomulco, a planned new transfer station for Line 8 (between Escuadrón 201 and Atlalilco) to Tláhuac. The second stage, connecting Mixcoac to Tláhuac, was to be completed in 2010.

Construction of Line 12 started in 2008, assuring it would be opened by 2011. Nevertheless, completion was delayed until 2012. Free test rides were offered to the public in some stations, and the line was fully operational on 30 October 2012. With minor changes, Line 12 runs from Mixcoac to Tláhuac, serving southern Mexico City for the first time. At 24.31 km long, it is the longest line in the system.

Line 12 differs from previous lines in several aspects: no hawkers are allowed, either inside the train or inside the stations; it is the first numbered line to use steel railway tracks; one must have a Tarjeta DF smart card to access any station since Metro tickets are no longer accepted.

In the book Los hombres del Metro, the original planning of Line 12 is described; although it was to begin at Mixcoac as it does today, Atlalilco and Constitución de 1917 stations of Line 8 were to be part of Line 12. The same map shows that Line 8 would have reached the Villa Coapa area and that it would not have had a terminal at Garibaldi, but at Indios Verdes, linking with Line 3. In addition, the book shows that Line 7 would have terminated at San Jerónimo. None of these plans have been confirmed by the Mexico City government.

In 2015, mayor Miguel Ángel Mancera announced the construction of two more stations and a terminal for Line 12: Valentín Campa, Álvaro Obregón and Observatorio, both west of Mixcoac. With this, Line 12 is to be connected to Line 1, providing new metro access to the Observatorio zone, which will become the terminal for the intercity train between Mexico City and Toluca.

Archaeological finds
The metro system's construction has resulted in more than 20 thousand archeological finds, from various time periods in the history of the indigenous people. The excavations needed to make way for the rails gave opportunities to find artifacts from different periods of the region's inhabitants, in areas that are now densely urbanized. Objects and small structures were found, with origins spanning from prehistoric times to the 20th century. Some examples of artifacts preserved by the Mexican National Institute of Anthropology and History (Instituto Nacional de Antropología e Historia de México (INAH)) are: parts of pyramids (like an altar to the Mexica god Ehecatl), a sculpture of the goddess Coatlicue, and remains of a mammoth. The altar to Ehécatl is now in Pino Suárez station, between lines 1 and 2, and is called by the INAH the smallest archeological site in Mexico. The metro has led to a large quantity of archeological finds, and has also let archaeologists understand more about the pattern of ancient civilisations in the Mexican capital by analysing its underground from various time periods.

Architecture
Distinguished architects were hired to design and construct the stations on the first metro line, such as Enrique del Moral, Félix Candela, Salvador Ortega and Luis Barragán. Examples of Candela's work can be seen in San Lázaro, Candelaria, and Merced stations on Line 1.

Cultural References
The Metro has figured in Mexico's cultural history, as the inspiration for a musical composition for strings, "Metro Chabacano" and Rodrigo "Rockdrigo" González's 1982 song, "Metro Balderas". It was also a filming location for the 1990 Hollywood movie Total Recall. Public intellectual Carlos Monsiváis has commented on the cultural importance of the Metro, "a space for collective expression, where diverse social sectors are compelled to mingle every day".

Lines, stations, names, colors, and logos
Each line offers one service only, and to each line, a number (letter if feeding line) and color are assigned. Every assigned color is present on square-shaped station logos, system maps and street signs, and neither colors nor numbers have been changed. Line B is the only exception to the color assignment, as green (upper half) and grey (lower half) are used, producing thus bicolor logos and signs. Gray only may be used to avoid confusion with line 8, which uses a similar green.

The names of metro stations are often historical in nature, highlighting people, places, and events in Mexican history. There are stations commemorating aspects of the Mexican Revolution and the revolutionary era. When it opened in 1969 with line 1 (the "Pink Line"), two stations alluded to the Revolution. Most directly referencing the Revolution was Pino Suárez, named after Francisco I. Madero's vice president, who was murdered with him in February 1913. The other was Balderas, whose icon is a cannon, alluding to the Ciudadela armory where the coup against Madero was launched. In 1970, Revolución opened, with the station at the Monument to the Revolution. As the Metro expanded, further stations with names from the revolutionary era opened. In 1980, two popular heroes of the Revolution were honored, with Zapata explicitly commemorating the peasant revolutionary from Morelos. A sideways commemoration was División del Norte, named after the Army that Pancho Villa commanded until its demise in the Battle of Celaya in 1915.

The year 1987 saw the opening of the Lázaro Cárdenas station. In 1988, Aquiles Sedán honors the first martyr of the Revolution. In 1994, Constitución de 1917 opened, as did Garibaldi, named after the grandson of Italian fighter for independence, Giuseppe Garibaldi. The grandson had been a participant in the Mexican Revolution. In 1999, the radical anarchist Ricardo Flores Magón was honored with the station of the same name. Also opening in 1999 was Romero Rubio, named after the leader of Porfirio Díaz's Científicos, whose daughter, Carmen Romero Rubio, became Díaz's second wife. In 2012, a new Metro line opened with an Hospital 20 de Noviembre stop, a hospital named after the date that Francisco I. Madero in his 1910 Plan de San Luis Potosí called for rebellion against Díaz. There are no Metro stops named for Madero, Carranza, Obregón, or Calles, and only an oblique reference to Villa in Metro División del Norte.

Each station is identified by a minimalist logo, first designed by Lance Wyman, who had also designed the logo for the 1968 Mexico Olympics. Logos are generally related to the name of the station or the area around it. At the time of Line 1's opening, Mexico's illiteracy rate was high. As of 1960, 38% of Mexicans over the age of five were illiterate and only 5.6% of Mexicans had completed elementary school. Since one-third of the Mexican population could not read or write and most of the rest had not completed high school, it was thought that patrons would find it easier to guide themselves with a system based on colors and visual signs.

The logos are not assigned at random; rather, they are designated by considering the surrounding areas, such as:
 * The reference places that are located around the stations (e.g., the logo for Salto del Agua fountain depicts a fountain).
 * The topology of an area (e.g., Coyoacán—in Nahuatl "place of coyotes"—depicts a coyote).
 * The history of the place (e.g., Juárez, named after President Benito Juárez, depicts his silhouette).

The logos' background colors reflect those of the line the station serves. Stations serving two or more lines show the respective colors of each line in diagonal stripes, as in Salto del Agua. This system was adopted for the Guadalajara and Monterrey metros, and for the Mexico City Metrobús. Although logos are no longer necessary due to literacy being now widespread, their usage has remained.

Under construction:

Transfers to other systems
The Mexico City Metro offers in and out-street transfers to four major rapid transit systems: the Mexico City Metrobús and State of Mexico Mexibús bus rapid transit systems, the Mexico City light rail system and the Ferrocarril Suburbano (FSZMVM) commuter rail. None of these are part of the Sistema de Transporte Colectivo network and an extra fare must be paid for access.

Metrobús line 1 was inaugurated in 2005. According to the 1985 STC Metro Master Plan, Metrobús Line 1 roughly follows the route planned for STC Metro Line 15 by 2010, which was never built. Every transfer is out-of-station, but the same smart card may be used for payment. All five lines (Line 5 to be built during 2013) offer a connection to at least one STC Metro station. STC Metro stations that connect to Metrobús lines include Indios Verdes, La Raza, Chilpancingo, Balderas, Etiopía / Plaza de la Transparencia, Insurgentes Sur and others.

The sole light rail line running from Tasqueña to Xochimilco is operated by the Servicio de Transportes Eléctricos and is better known as Tren Ligero. Line 2 terminal Tasqueña offers an in-station transfer, but an extra ticket must be purchased.

In 2008, the Ferrocarril Suburbano commuter rail, commonly known as Suburbano, was inaugurated with a sole line running from Cuatitlán to Buenavista as of 2013. STC Metro offers two in-station transfers: Line B terminal Buenavista to the Suburbano terminal of the same name, and Line 6 station Ferrería / Arena Ciudad de México into Suburbano station Fortuna. An extra fare must be paid, and a Ferrocarril Suburbano smart card is required for access.

Another commuter rail, Tren Interurbano de Pasajeros Toluca-Valle de México is estimated to be completed in 2023. This line will connect Observatorio station in Mexico City with Toluca.

Fares and pay systems
A single ticket, currently MXN $5.00, allows a rider one trip anywhere within the system with unlimited transfers. A discounted rate of MXN $3.00 is available upon application for women head of households, the unemployed, and students with scarce resources. Mexico City Metro offers free service to the elderly, the physically impaired, and children under the age of 5 (accompanied by an adult). Tickets can be purchased at booths. They are made of paper and have a magnetic strip on them, and are recycled upon being inserted into a turnstile.

Until 2009, a STC Metro ticket cost MXN $2.00 (€ 0.10, or US$ 0.15 in 2009); one purchased ticket allowed unlimited distance travel and transfer at any given time for one day, making the Mexico City Metro one of the cheapest rail systems in the world. Only line A's transfer in Pantitlán required a second payment before 13 December 2013. In January 2010, the price rose to MXN $3.00 (€ 0.15, or US$ 0.24), a fare that remained until 13 December 2013; a 2009 survey showed that 93% of citizens approved of the increase, while some said they would be willing to pay even more if needed.

STC Metro rechargeable cards were first available for an initial cost of MXN $10.00. The card would be recharged at the ticket counter in any station (or at machines in some Metro stations) to a maximum of MXN $120.00 (around € 6.44, or US$ 7.05 in 2015) for 24 trips.

In an attempt to modernize public transport, in October 2012, the Mexico City government implemented the use of a prepaid fare card, or stored-value card, called Tarjeta DF (Tarjeta del Distrito Federal, literally Federal District Card) as a payment method for STC Metro, Metrobús and the city's trolleybus and light rail systems, though they are all managed by different organizations. Servicio de Transportes Eléctricos manages both the Xochimilco Light Rail line and the city's trolleybus system. Previous fare cards that were valid only on STC Metro or Metrobús remained valid for the system for which they were acquired.

Rolling stock

As of April 2012, 14 types of standard gauge rolling stock totalling a number of 355 trains running in 6-or 9-car formation are currently in use on the Mexico City Metro. Most of the stock is rapid transit type, with the exception of the Line A stock, which is light metro. Four manufacturers have provided rolling stock for the Mexico City Metro, namely the French Alstom (MP-68, NM-73, NM-79), Canadian Bombardier (FM-95A and NM-02), Spanish CAF (NM-02, FE-07, FE-10 and NM-16 and Mexican Concarril (NM-83 and FM-86) (now Bombardier Transportation Mexico, in some train types with the help of Alstom and/or Bombardier).

The maximum design speed limit is 80 km/h (average speed 35.5 km/h) for rubber-tired rolling stock and 100 km/h (average speed 42.5 km/h) for steel-wheeled rolling stock. Forced-air ventilation is employed and the top portion of windows can be opened so that passenger comfort is enhanced by the combination of these two types of ventilation. Like the rolling stock used in the Paris Métro and the Montreal Metro, the numbering of the Mexico City Metro's rolling stock are specified by year of design (not year of first use).

In chronological order, the types of rubber-tired rolling stock are: MP-68, NM-73A, NM-73B, NM-73C, NM-79, MP-82, NC-82, NM-83A, NM-83B, NE-92, NM-02, NM-16 and NM-22; and the types of steel-wheeled rolling stock are: FM-86, FM-95A, FE-07, and FE-10.

From May 2024, Line 1 will receive 29 new rubber-tired trains manufactured by CRRC Zhuzhou Locomotive in China, replacing earlier rolling stock. This is in line with ongoing upgrading works for Line 1, including the installation of CBTC.

Major incidents
On 20 October 1975, two trains crashed in Viaducto station while both were going towards Tasqueña station. The first was stopped picking up passengers when it was hit by another train that did not stop in time. According to official reports, from 31 to 39 people died, and between 71 and 119 were injured. After the crash, automatic signals were incorporated to all lines.

On 18 September 2009, a man was vandalizing the walls of Balderas station with a marker before being confronted by a police officer. He took out a gun and killed the officer and a construction worker who tried to disarm him, and injured 5 others.

On 4 May 2015, two trains heading towards Politécnico station on Line 5 crashed in Oceanía station. The first was leaving to Aragón station and was requested to stop and wait, while the second did not deactivate the autopilot and crashed into it at the end of the platform. 12 people were injured.

On 10 March 2020, two trains heading towards Observatorio station on Line 1 crashed in Tacubaya station. The first train was parked at the platform when it was hit by another train that was coming in reverse. 1 person died and 41 were injured, all inside the second train, as people in the parked train had been evacuated moments before the crash.

On 9 January 2021, the Central Control Center serving lines 1 to 6 caught fire. During the fire, a female police officer was killed due to a fall in the building. All the stations on those lines temporarily remained closed and provisional transport service was provided by city buses and police vehicles. According to the Metro authorities, the service in lines 4, 5, and 6 would be normalized in days, while that in lines 1, 2, and 3 in several months.

On 3 May 2021, a train was traveling on Line 12 between the Olivos and Tezonco stations when a girder supporting the overpass on which the train was traveling collapsed, killing 26 and injuring more than 70. Service on Line 12 was later suspended, while STC warned residents to avoid the site of the collapse.

On 7 January 2023 at 09:16 local time, two trains collided between Potrero and La Raza stations on Line 3, killing one and injuring 57. In addition to other minor events,  city officials said that this accident was a result of sabotage to the Fourth Transformation platform to affect the image of Claudia Sheinbaum, then mayor of the city and a potential candidate on the 2024 Mexican general election.

title: Mexico City Metro


text:
Henck Arron

Henck Alphonsus Eugène Arron (25 April 1936 – 4 December 2000) was a Surinamese politician who served as the first Prime Minister of Suriname after it gained independence in 1975. A member of the National Party of Suriname, he served from 24 December 1973 with the transition government, to 25 February 1980. He was overthrown in a coup d'état by the military, led by Dési Bouterse. Released in 1981 after charges of corruption were dropped, he returned to banking, his previous career. In 1987, Arron was elected as Vice President of Suriname and served until another coup in 1990 overthrew the government.

Biography
Arron was born in Paramaribo in 1936. He completed high school in 1956, and moved to the Netherlands to study banking. Arron worked several years at the Amsterdamsche Bank. On return to Suriname, he became staff member at the Vervuurts Bank (current name Hakrinbank). In late 1963, he became deputy director of the Volkskredietbank (People's Credit Union).

In 1961, Arron became a member of the National Party of Suriname (NPS), the main Creole party. In 1970, Arron was chosen as the Chairman of the NPS. In 1973, he created a coalition which included the pro-independence Nationalist Republican Party (PNR), that won that year's general election. On 24 December 1973, Arron became prime minister, and lead the final negotiation for the independence of Suriname. The NPS found an ally in the Dutch PvdA who wanted independence as soon as possible. In February 1974, Arron announced that Suriname would be seeking independence before the end of 1975. Many observers were surprised, as Arron's NPS did not have a majority in favour of independence.

The Netherlands granted Suriname independence on 25 November 1975. The independence was marked by social unrest, economic depression, and rumours of corruption. Its leaders were accused of fraud in the 1977 elections, in which Arron won a further term. During the first years of independence about one-third of the population emigrated to the Netherlands.

The hastily created Suriname National Army had many non-commissioned officers who tried to unionise complaining about corruption, and poor pay. Arron refused to recognise them, and arrested the ringleaders who were to go to trial on 26 February 1980. Also, elections were planned for March of that year. On 25 February, Arron was overthrown and jailed in a coup by the military led by Dési Bouterse. In 1981, Arron was released under house arrest. A year later, he was selected as managing director of the Surinamese People's Credit Bank.

In 1987, the United Nations, Netherlands, France, and United States pressured the military government to negotiate, and Suriname saw a return to democracy. That year Arron was elected as Vice President of Suriname (and therefore Chairman of the Council of Ministers), serving from 26 January 1988 to 24 December 1990. Ramsewak Shankar was elected as president. Their government was overthrown in 1990 in another coup by Bouterse and the military.

In December 2000, Arron was invited by the Royal Tropical Institute to the Netherlands to talk about 25 years of Surinamese independence. On the evening of 4 December, he died at the home of his brother as a result of cardiac arrest.

Honours

 * Suriname: Grand Cordon (Grootlint), Honorary Order of the Yellow Star (2000)

title: Henck Arron