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Sanctus

The Sanctus (Sanctus, "Holy") is a hymn in Christian liturgy. It may also be called the epinikios hymnos (ἐπινίκιος ὕμνος, "Hymn of Victory") when referring to the Greek rendition and parts of it are sometimes called "Benedictus". Tersanctus (Latin: "Thrice Holy") is another, rarer name for the Sanctus. The same name is sometimes used for the Trisagion.

In Western Christianity, the Sanctus forms part of the Ordinary and is sung (or said) as the final words of the Preface of the Eucharistic Prayer of remembrance, consecration, and praise. The preface, which alters according to the season, usually concludes with words describing the praise of the worshippers joining with the angels, who are pictured as praising God with the words of the Sanctus. In the Byzantine Rite and general Eastern Orthodox Christianity, the Sanctus is offered as a response by the choir during the Holy Anaphora.

In Greek
Ἅγιος, ἅγιος, ἅγιος Κύριος Σαβαώθ· πλήρης ὁ οὐρανὸς καὶ ἡ γῆ τῆς δόξης σου, ὡσαννὰ ἐν τοῖς ὑψίστοις. Εὐλογημένος ὁ ἐρχόμενος ἐν ὀνόματι Κυρίου. Ὡσαννὰ (ὁ) ἐν τοῖς ὑψίστοις. ''Hágios, hágios, hágios, Kýrios Sabaṓth; plḗrēs ho ouranós kaí hē gê tês dóxēs sou, hōsanná en toîs hupsístois. Eulogēménos ho erkhómenos en onómati Kyríou. Hōsanná (ho) en toîs hupsístois.''

In the Divine Liturgy of St. John Chrysostom and the Liturgy of St. Basil: Ἅγιος, ἅγιος, ἅγιος Κύριος Σαβαώθ· πλήρης ὁ οὐρανὸς καὶ ἡ γῆ τῆς δόξης σου, ὡσαννὰ ἐν τοῖς ὑψίστοις. Εὐλογημένος ὁ ἐρχόμενος ἐν ὀνόματι Κυρίου. Ὡσαννὰ ὁ ἐν τοῖς ὑψίστοις.

Hágios, hágios, hágios, Kýrios Sabaṓth; plḗrēs ho ouranós kaí hē gê tês dóxēs sou, hōsanná en toîs hupsístois. Eulogēménos ho erkhómenos en onómati Kyríou. Hōsanná ho en toîs hupsístois.

In the Liturgy of St. James: Ἅγιος, ἅγιος, ἅγιος Κύριος Σαβαώθ. Πλήρης ὁ οὐρανὸς καὶ ἡ γῆ τῆς δόξης σου. Ὡσαννὰ ἐν τοῖς ὑψίστοις. Εὐλογημένος ὁ ἐρχόμενος ἐν ὀνόματι Κυρίου. Ὡσαννὰ ἐν τοῖς ὑψίστοις.

Hágios, hágios, hágios, Kýrios Sabaṓth. Plḗrēs ho ouranós kaí hē gê tês dóxēs sou. Hōsanná en toîs hupsístois. Eulogēménos ho erkhómenos en onómati Kyríou. Hōsanná ho en toîs hupsístois.

In Latin
In the Roman Rite: Sanctus, Sanctus, Sanctus Dominus Deus Sabaoth. Pleni sunt cæli et terra gloria tua. Hosanna in excelsis. Benedictus qui venit in nomine Domini. Hosanna in excelsis.

In the Roman Rite, the Sanctus also forms part of the solemn hymn of praise Te Deum laudamus, but with the addition of a reference to the "majesty" of the Lord's glory in the Pleni sunt verse (the phrase pleni sunt caeli et terra gloria tua becomes pleni sunt caeli et terra maiestatis gloriae tuae). The Benedictus is not included in the Te Deum, and the Sanctus is therefore included as part of that hymn as follows:

Sanctus, Sanctus, Sanctus, Dominus Deus Sabaoth. Pleni sunt cæli et terra maiestatis gloriæ tuæ.

In the Mozarabic Rite: Sanctus, Sanctus, Sanctus, Dominus Deus Sabaoth: Pleni sunt cæli et terra gloria maiestatis tuæ, Hosanna filio David. Benedictus qui venit in nomine Domini. Hosanna in excelsis. Hagios, hagios, hagios Kyrie o Theos.

In English
The Sanctus appears thus in the 1549 Book of Common Prayer (and as set to music by John Merbecke in 1550 ): Holy, holy, holy, lorde God of hostes. heaven and earth are full of thy glory Osanna in the highest. Blessed is he that commeth in the name of the lorde: Glory to the, o lorde in the highest.

In the 1552 Book of Common Prayer and 1559 BCP it appears without the Benedictus: Holy, holy, holy, lord god of hostes, heven and earth are ful of thy glory, glory be to the, O Lord most hyghe.

The 1662 BCP has it thus:

Holy, Holy, Holy, Lord God of hoſts, heaven and earth are full of thy glory; Glory be to thee, O Lord Moſt High.

Later Anglican prayer books following the ritualist and liturgical movements of the twentieth century, restored the Benedictus to this form, yielding: Holy, holy, holy, Lord God of hosts, heaven and earth are full of thy glory. Glory be to thee, O Lord most high. Blessed is he that cometh in the name of the Lord. Hosanna in the highest. The following English version was used by most Lutherans in North America until 1978 when the ICET version was adopted in the Lutheran Book of Worship. This traditional version has continued to be used in the Divine Service of the Lutheran Church—Missouri Synod: Holy, holy, holy, Lord God of Sabaoth; heaven and earth are full of thy glory. Hosanna in the highest. Blessed is He that cometh in the name of the Lord Hosanna in the highest.

In 1973 the International Consultation on English Texts (ICET) produced an ecumenical version that at that time was adopted by Catholics, Anglicans, Lutherans, Methodists and others: Holy, holy, holy Lord, God of power and might, heaven and earth are full of your glory. Hosanna in the highest. Blessed is he who comes in the name of the Lord. Hosanna in the highest.

Since 2011 the Roman Missal in English has: Holy, Holy, Holy Lord God of hosts. Heaven and earth are full of your glory. Hosanna in the highest. Blessed is he who comes in the name of the Lord. Hosanna in the highest.

In Coptic
As part of the Alexandrian rite, the Benedictus is not present in the Liturgy of Saint Cyril: Αγιος, αγιος, αγιος. Ⲭⲟⲩⲁⲃ `Ⲡϭⲟⲓⲥ ⲥⲁⲃⲁⲱⲑ: `ⲧⲫⲉ ⲛⲉⲙ `ⲡⲕⲁϩⲓ ⲙⲉϩ ⲉⲃⲟⲗϧⲉⲛ ⲡⲉⲕⲱⲟⲩ ⲉⲑⲟⲩⲁⲃ `Ⲡϭⲟⲓⲥ Ⲡⲉⲛⲛⲟⲩϯ.

Hymn forms in Eastern liturgies
The present form of the Divine Liturgy of St. John Chrysostom, the primary liturgy of the Eastern Orthodox Church, reads (when in Greek) the following text: Ἅγιος, ἅγιος, ἅγιος Κύριος Σαβαώθ· πλήρης ὁ οὐρανὸς καὶ ἡ γῆ τῆς δόξης σου, ὡσαννὰ ἐν τοῖς ὑψίστοις. Εὐλογημένος ὁ ἐρχόμενος ἐν ὀνόματι Κυρίου. Ὡσαννὰ ὁ ἐν τοῖς ὑψίστοις.

''Hágios, hágios, hágios Kýrios Sabaṓth; plḗrēs ho ouranós kaí hē gê tês dóxēs sou, hōsanná en toîs hupsístois. Eulogēménos ho erkhómenos en onómati Kyríou. Hōsanná ho en toîs hupsístois.''

The above differs from the Roman Rite Latin text
 * in that the Latin adds to the word Dominus (Lord), which is the regular Latin translation of יהוה, the Deus (God), which is found in neither the Greek nor the Latin translations nor in the original text of Isaiah 6:3,  but is found in : "Holy, holy, holy, is the Lord God Almighty, who was and is and is to come!"
 * in that the Latin has the plural caeli, and the Greek the singular οὐρανός for the mention of "heaven", which appears in neither the Latin nor the Greek translation of Isaiah 6:3.
 * in that the Greek gives two different forms of the phrase corresponding to Hosanna in excelsis, the second one including an ὁ article. The article is not found in Matthew 21:9. The form of the hymn without the article is also used in the Greek Liturgy of Saint James, and in modern settings, practises and contexts.

The Liturgy of Saint Basil of the Eastern Orthodox Church has the same form of the Sanctus as the Liturgy of Saint John Chrysostom, with its two variants of the Hosanna phrase.

In older Greek liturgical manuscripts, various forms of the hymn are attested; the ones that will follow below, belong to the ones edited by Swainson in his 1884 book The Greek liturgies. Among these forms, there are variations of the hymn being composed of practically only the Old testament part. Others include: In the Liturgy of Saint John Chrysostom, one of them excludes not only the article ὁ, but also the article «τῆς»: Ἅγιος, ἅγιος, ἅγιος, Κύριος Σαβαώθ· πλήρης ὁ οὐρανὸς καὶ ἡ γῆ δόξης σου. Ὡσαννὰ ἐν τοῖς ὑψίστοις· εὐλογημένος ὁ ἐρχόμενος ἐν ὀνόματι Κυρίου· ὡσαννὰ ἐν τοῖς ὑψίστοις.

''Hágios, hágios, hágios, Kýrios Sabaṓth; plḗrēs ho ouranós kaí hē gê dóxēs sou. Hōsanná en toîs hupsístois; eulogēménos ho erkhómenos en onómati Kyríou; hōsanná en toîs hupsístois.''

The Liturgy of Saint James as given in Swainson reads as follows: Ἅγιος, ἅγιος, ἅγιος, Κύριε σαβαώθ· πλήρης ὁ οὐρανὸς καὶ ἡ γῆ τῆς δόξης σου· ὡσαννὰ ἐν τοῖς ὑψίστοις. Eὐλογημένος ὁ ἐρχόμενος ἐν ὀνόματι Κυρίου· ὡσαννὰ ἐν τοῖς ὑψίστοις.

''Hágios, hágios, hágios, Kýrie sabaṓth. Plḗrēs ho ouranós kaí hē gê tês dóxēs sou; hōsanná en toîs hupsístois. Eulogēménos ho erkhómenos en onómati Kyríou; hōsanná en toîs hupsístois.''

This text not only omits the article ὁ that is used in the Liturgy of Saint John Chrysostom, but also has Kyrie (vocative case) where the Liturgy of Saint John Chrysostom has Kyrios (nominative).

In current use, the Liturgy of Saint James may use the nominative rather than the vocative case of Κύριος; the article ὁ is also not present in this form at the concluding Hosanna.

Moreover, a different variant of the Liturgy of Saint James is found in the margin of a manuscript that gives only the three words Ἅγιος, ἅγιος, ἅγιος in the body: "In the margin, much abbreviated, may be discerned the following: Κύριος σαβαώθ, πλήρης ὁ οὐρανὸς καὶ ἡ γῆ τῆς δόξης σου. Ὡσαννὰ ἐν τοῖς ὑψίστοις· εὐλογημένος ὁ ἐλθὼν καὶ ἐρχόμενος ἐν ὀνόματι Κυρίου· ὡσαννὰ ἐν τοῖς ὑψίστοις. This produces the text: Ἅγιος, ἅγιος, ἅγιος, Κύριος σαβαώθ, πλήρης ὁ οὐρανὸς καὶ ἡ γῆ τῆς δόξης σου· ὡσαννὰ ἐν τοῖς ὑψίστοις. Εὐλογημένος ὁ ἐλθὼν καὶ ἐρχόμενος ἐν ὀνόματι Κυρίου· ὡσαννὰ ἐν τοῖς ὑψίστοις.

''Hágios, hágios, hágios, Kýrios Sabaṓth, plḗrēs ho ouranós kaí hē gê tês dóxēs sou; hōsanná en toîs hupsístois. Eulogēménos ho elthṓn kaí erkhómenos en onómati Kyríou; hōsanná en toîs hupsístois.''

This version adds "he who came and" before "he who comes"; in this it resembles the Liturgy of Saint James in the tradition of the Syriac Orthodox Church: "Holy, holy, holy, Lord God Almighty; heaven and earth are full of His glories. Hosanna in the highest. Blessed is He Who came and will come in the Name of the Lord. Hosanna in the highest."

The Syriac Orthodox Church also has what it calls the Liturgy of Saint Dionysius, in which the Hosanna phrase appears only at the end: "Holy Holy Holy, Lord of Sabbaoth, Heaven and Earth are full of Thy Glory. Blessed is He that cometh in the Lord's Name; Hosanna in the highest."

The form used in the ancient Liturgy of Addai and Mari is much shorter: ܩܲܕܝܫ: ܩܲܕܝܼܫ: ܩܲܕܝܼܫ: ܡܵܪܝܵܐ ܐܲܠܵܗܵܐ ܚܲܝܠܬ݂ܵܢܵܐ: ܕܲܡܠܹܝܢ ܫ̈ܡܲܝܵܐ ܘܐܲܪܥܵܐ ܡܸܢ ܬܸܫ̈ܒ݁ܚܵܬܹܗ: ܘܡܸܢ ܟܝܵܢ ܐܝܼܬ݂ܘܼܬܹܗ: ܘܡܸܢ ܗܸܕ݂ܪܵܐ ܕܙܝܼܘܹܗ ܡܫܲܒ݁ܚܵܐ܀ ܐܘܿܫܲܥܢܵܐ ܒܲܡܪ̈ܲܘܡܹܐ: ܐܘܿܫܲܥܢܵܐ ܠܲܒ݂ܪܹܗ ܕܕ݂ܵܘܝܼܕ݂: ܒܪܝܼܟ݂ ܕܐܸܬ݂ܵܐ ܘܐܵܬܹܐ ܒܲܫܡܹܗ ܕܡܵܪܝܵܐ: ܐܘܿܫܲܥܢܵܐ ܒܲܡܪ̈ܲܘܡܹܐ.

Holy, Holy, Holy Lord is the Lord God of hosts, for heaven and earth are full of his praises, and of the nature of his being, and for the excellency of his glorious splendor. Hosanna in the heights. Hosanna to the son of David. Blessed is he who came and will come in the name of the Lord. Hosanna in the heights.

The Coptic version of the Liturgy of Saint Basil also gives a short text of what it calls the Hymn of the Seraphim: "Holy, Holy, Holy, Lord of hosts; Heaven and earth are full of Your holy glory."

Alternative ancient names and ancient secrecy
The priest's introductions, following the rubrics that set what should be done by whom with each passage, uniformly call the hymn the ἐπινίκιος ὕμνος, i.e. "the hymn of victory". On the other hand, it used to be that, as Swainson notes about an attested variant form wherein only Ἅγιος, ἅγιος, ἅγιος is being quoted: "In the margin, much abbreviated, may be discerned the following: Κύριος σαβαώθ, πλήρης ὁ οὐρανὸς καὶ ἡ γῆ τῆς δόξης σου. Ὡσαννὰ ἐν τοῖς ὑψίστοις· εὐλογημένος ὁ ἐλθὼν καὶ ἐρχόμενος ἐν ὀνόματι Κυρίου· ὡσαννὰ ἐν τοῖς ὑψίστοις. Chrysostom frequently refers to this: sometimes as τὸ μυστικὸν μέλος; sometimes as ὁ πανάγιος ὕμνος; sometimes as the τρισάγιος ὕμνος. The knowledge of it as a whole was confined to the faithful."

 * Sanctus, Sanctus, Sanctus Dominus Deus Sabaoth; pleni sunt coeli et terra gloria tua
 * Holy, Holy, Holy Lord God of Hosts; Heaven and earth are full of Your glory.
 * Hosanna in excelsis
 * Hosanna in the highest
 * Benedictus qui venit in nomine Domini.
 * Blessed is He who comes in the name of the Lord
 * Hosanna in excelsis

Musical settings
The Sanctus has been set to numerous plainchant melodies, many of which are given in the Roman Missal, and many more composers have set it to polyphonic music, both in single settings and as part of cyclic mass settings.

Parts of the Hymn have also been used in modern music, notably "Prism of Life" by Enigma (album Le Roi Est Mort, Vive Le Roi!)

Accompanying gestures
In the Tridentine Mass the priest joins his hands while saying the word "Sanctus" and then, bowing, continues to recite the whole of the Sanctus in a lower voice, while a small bell is rung; then, on reaching the words "Benedictus qui venit in nomine Domini", he stands erect again and makes the Sign of the Cross. He then continues immediately with the Canon of the Mass, while the choir, if there is one, sings the Sanctus. In the pre-1962 form, the choir pauses for the Consecration and continues with the Benedictus part afterwards. As a result of this division, the Sanctus has sometimes been spoken of as "Sanctus and Benedictus". However, in line with Pope John XXIII's revision of the rubrics of the liturgy, the splitting of the Sanctus, when sung to Gregorian chant (though not if sung polyphonically) was forbidden and is thus not allowed in celebrations of the 1962 Tridentine Mass as authorized by Pope Benedict XVI's Summorum Pontificum.

In the Mass revised after the Second Vatican Council, the Sanctus may, of course, not be split, since the whole of the eucharistic prayer is sung or spoken aloud, and the only ceremony prescribed for the priest during the Sanctus is to join his hands. He and the people sing or recite together the whole of the Sanctus, before the priest continues the Eucharistic Prayer.

Use in architecture and art
Words of the Sanctus are often used in church architecture and Christian art.

title: Sanctus


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Seine–Oise–Marne culture

The Seine–Oise–Marne or SOM culture is the name given by archaeologists to the final culture of the Neolithic and first culture of the  Chalcolithic in northern France and southern Belgium.

It lasted from around 3100 to 2000 BCE and is most famous for its gallery grave megalithic tombs, which incorporate a port-hole slab separating the entrance from the main burial chamber. In the chalk valley of the River Marne, rock-cut tombs (hypogea) were dug to a similar design. Some have examples of megalithic art with images of axes, breasts, and necklaces carved on their walls.

Diagnostic artefacts include transverse arrowheads, antler sleeves and crude, flat-based cylindrical and bucket-shaped pottery decorated with appliqué cordons. The SOM culture had trade links with neighbouring cultures enabling the use of Callaïs and Grand Pressingy flint imported from Brittany and the Loire and later, the use of copper.

The culture seems to have had strong links with other areas and may have arisen from a composite of influences as indicated by the gallery grave design common across Europe and the pottery types which have comparators in Western France from 2600BC and also in Brittany, Switzerland and Denmark.

Genetic profile
Ten individuals dated between 3400 to 2900 BC were tested from two collective burial hipogea of the Mont-Aimé site (Val-des-Marais, Marne department); six out of seven males were assigned to the Y-chromosome haplogroup I2a1b1b1 (Y13335), and there was an individual belonging to haplogroup H2a1a. The autosomal components were a mix of European farmer and Western hunter-gatherer (this one ranging from a minimum of 20% to a maximum of 55%). Two males buried in the Pierre Fritte dolmen (Yermenonville, Eure et Loire department) had the same mitochondrial haplogropup K and Y-DNA haplogroup I2a1.

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

title: Seine–Oise–Marne culture


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Albert Nelson (actor)

Albert Nelson is an American-born actor who appeared in the 1976 David Bowie film The Man Who Fell to Earth as well the horror movie The Prophecy. He has also appeared in numerous television dramas and commercials.

Filmography

 * The Man Who Fell to Earth (1976) (Waiter)
 * The Prophecy (1995) (Grey Horse)

title: Albert Nelson (actor)


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USS Cutlass

USS Cutlass (SS-478), is a Tench-class submarine now in the service of the Republic of China Navy. She was the only ship of the United States Navy to be named for the cutlassfish, a long, thin fish found widely along the coasts of the United States and in the West Indies. Her keel was laid down by the Portsmouth Navy Yard on 10 July 1944. She was launched on 5 November 1944 sponsored by Mrs. R. E. Kintner, and commissioned on 17 March 1945 with Commander Herbert L. Jukes in command.

1945–1973 (US Navy)
Departing Portsmouth, New Hampshire, on 25 April 1945, Cutlass arrived at Pearl Harbor on 15 July and put out on her maiden war patrol two days later. Assigned to patrol in the vicinity of the Kurile Islands, she entered the area one day after the announced Japanese surrender, remained on observation patrol until 24 August, then returned to Pearl Harbor. She sailed on 2 September for New York, arriving 24 September to receive visitors through Navy Day.

Cutlass cruised on the East Coast until 8 January 1946 when she cleared for the Panama Canal Zone. Except for three months of operations in Delaware Bay, Cutlass remained in the Caribbean Sea, based at Cristóbal, Canal Zone. From 23 August to 2 October 1947 she made a cruise down the coast of South America, around Cape Horn, visited Valparaíso, Chile, and returned to the east coast of South America through the Straits of Magellan.

Cutlass left the Panama Canal Zone 6 January 1948 for local operations at Key West, Florida, then entered Philadelphia Naval Shipyard in March for overhaul and modernization. Arriving at Key West 7 February 1949 she served as test submarine for Operation "Rainbow" evaluating color schemes to enhance livability, a serious problem in new submarines with long submergence capability. She continued to sail out of Key West until the summer of 1952 when her home port was changed to Norfolk, Virginia.

In 1953 Cutlass cruised to the Mediterranean Sea, visiting France, Greece, Turkey, North Africa, Gibraltar, Malta, and Spain, then sailed in Cuban waters to act as target for destroyers and aircraft engaged in antisubmarine exercises. She joined in local operations, fleet exercises and antisubmarine warfare training in the Caribbean Sea until September 1956 when she departed for the Mediterranean and operations with NATO forces including the Sixth Fleet. She visited Italy, Greece, Crete, Majorca, Portugal and England, returning to Norfolk in December. In 1958 she sailed on a north European cruise, visiting Rosyth, Scotland, Copenhagen and Korsor, Denmark, and passing through the Kiel Canal.

In the first half of 1959, Cutlass joined in the antisubmarine warfare development work of Task Force "Alfa" off the Virginia Capes, and in September sailed for the Mediterranean. In November she passed through the Suez Canal to join ships of the Pakistani Navy in exercises off Karachi, returning to Norfolk in December. After continued operations with TF "Alfa," she entered Philadelphia Naval Shipyard in February 1960 for an overhaul which continued until August. Cutlass was decommissioned and struck from the Naval Vessel Register on 15 April 1973.

1973–present (Taiwan)
On 4 December 1973, Cutlass had her torpedo tubes sealed and was sold to Taiwan, where she was commissioned in the Republic of China Navy as ROCS Hai Shih (SS-791), (meaning "sea lion"). They then tried to restore her torpedo capabilities. In January 2017, Taiwan announced that she would receive a retrofit to extend her service life until 2026, making her the longest-serving submarine in history. The submarine is still operational and reportedly capable of combat. The $19 million retrofit was to improve the hull and the diesel vessel's navigational elements.

title: USS Cutlass


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Casomorphin

Casomorphin is an opioid peptide (protein fragment) derived from the digestion of the milk protein casein.

Health
Digestive enzymes can break casein down into peptides that have some biological activity in cells and in laboratory animals though conclusive causal effects on humans have not been established.

Although research has shown high rates of use of complementary and alternative therapies for children with autism, including gluten and/or casein exclusion diets, there was a lack of evidence that these diets had any effect.

If opioid peptides breach the intestinal barrier, typically linked to permeability and constrained biosynthesis of dipeptidyl peptidase-4 (DPP4), they can attach to opioid receptors. Elucidation requires a systemic framework that acknowledges that public-health effects of food-derived opioids are complex with varying genetic susceptibility and confounding factors, together with system-wide interactions and feedbacks.

β-Casomorphins 1–3

 * Structure: H-Tyr-Pro-Phe-OH
 * Chemical formula: C23H27N3O5
 * Molecular weight: 425.48 g/mol

Bovine β-casomorphins 1–4

 * Structure: H-Tyr-Pro-Phe-Pro-OH
 * Chemical formula: C28H35N4O6
 * Molecular weight: 522.61 g/mol

Bovine β-casomorphin 1–4, amide
Also known as morphiceptin
 * Structure: H-Tyr-Pro-Phe-Pro-NH2
 * Chemical formula: C28H35N5O5
 * Molecular weight: 521.6 g/mol

Bovine β-casomorphin 5

 * Structure: H-Tyr-Pro-Phe-Pro-Gly-OH
 * Chemical formula: C30H37N5O7
 * Molecular weight: 594.66 g/mol

Bovine β-casomorphin 7

 * Structure: H-Tyr-Pro-Phe-Pro-Gly-Pro-Ile-OH
 * Chemical formula: C41H55N7O9
 * Molecular weight: 789.9 g/mol

Bovine β-casomorphin 8
(Note: There is also a form of bovine β-casomorphin 8 that has histidine instead of proline in position 8, depending on whether it is derived from A1 (His) or A2 (Pro) beta-casein.)
 * Structure: H-Tyr-Pro-Phe-Pro-Gly-Pro-Ile-Pro-OH
 * Chemical formula: C46H62N8O10
 * Molecular weight: 887.00 g/mol

title: Casomorphin


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Talk:Clean Skies Initiative

The Clean Skies Initiative is legislation proposed by President George W. Bush on September 17, 2003. It would expand the Acid Rain Program, the Clean Air Act's most successful program to cut air pollution. It would also mandate a 70 percent cut in air pollution from power plants over the next 15 years including the first-ever national cap on mercury emissions. Along with this, it would help cities and counties across America meet the Environmental Protection Agency's (EPA) stringent new health-based air quality standards for ozone and fine particles. Most importantly, it would improve air quality using a proven, market-based approach that will reach the Nation's air quality goals while keeping energy affordable for American consumers and businesses.

Source:

NPOV/Expanding
It's obvious that this article needs a lot of work, it's short and extremely one-sided at the moment. I'll probably have the time to do it myself in a week or two, but am adding the NPOV notice for the time being.

--Sfaok 21:57, 27 Apr 2005 (UTC)

Wrong Title
methinks you mean Clear Skies Act.... changing to a redir Feco 22:40, 31 May 2005 (UTC)

title: Talk:Clean Skies Initiative


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USS Remora

USS Remora (SS-487), a Tench-class submarine, was the only ship of the United States Navy to be named for the remora, a fish with a suctorial disk on its head enabling it to cling to other fish and to ships.

Construction and commissioning
Remora′s keel was laid down on 5 March 1945 by the Portsmouth Navy Yard in Kittery, Maine. She was launched on 12 July 1945, sponsored by Mrs. T. W. Samuels III, and commissioned on 3 January 1946 with Commander Robert Sellars in command.

Training submarine
Completing her Caribbean Sea shakedown in April 1946, Remora operated out of New London, Connecticut, as a training submarine until January 1947. Then transferred to the Pacific, she transited the Panama Canal at mid-month and arrived at Mare Island, Vallejo, California, on 14 February to begin a Greater Underwater Propulsive Power Program (GUPPY-II) conversion. Early in November, she completed trials and on 22 February arrived at San Diego, California, her new homeport.

Eastern Pacific
For the next two years, she remained in the eastern Pacific operating primarily off California, but during the summer and early fall of 1948, ranged as far north as the Aleutian Islands. On 1 May 1950 she headed west for her first deployment in the Far East. On 8 June she arrived at Sasebo, and on 11 June she shifted to Yokosuka, from which base she conducted anti-submarine warfare (ASW) training exercises with units of Naval Forces Far East. Two weeks later the Korean War began.

A unit of TF 96, Naval Forces Japan Remora patrolled Soya Strait, between Hokkaidō and Sakhalin in late July and early August. Later in the month, she headed back to San Diego. During the next two years she underwent overhaul, provided services for the Line School at Monterey, California, and conducted local training exercises. She returned to the western Pacific in early 1953. Arriving at Buckner Bay on 15 March, she continued on to Japan in April and at mid-month rejoined TF 96. In June she was back in Okinawan waters for patrols and exercises, after which she returned to Yokosuka. On 2 July she headed east, reaching San Diego on 3 August.

After the fighting in Korea ended, Remora remained based at San Diego and through the decade continued to alternate training exercises and patrols in the western Pacific with similar First Fleet operations off the United States West Coast and in Hawaiian waters. She remained in the eastern Pacific during 1956 and 1958, but, during the spring of the latter year, was engaged in extended exercises off Alaska.

Pearl Harbor
In November 1961, Remora was transferred from San Diego to Pearl Harbor. The following year she underwent a seven-month Greater Underwater Propulsive Power Program (GUPPY-III) conversion which lengthened her hull by 15 ft and her conning tower by five feet. Then, in 1963, she was employed to evaluate antisubmarine sonar in Hawaiian waters. In May 1964, she resumed a schedule of annual six-month WestPac deployments which she continued into 1969. Remora was one of the last diesel boats to receive the Navy Unit Commendation for "Meritorious Service for operations during the Summer and Fall of 1967." During a shipyard overhaul in late 1967 early 1968, Engine #1 was removed and replaced with a "Prairie Masker" system designed to mask her engines during snorkeling.

In July 1969, Remora shifted home ports, from Pearl Harbor to Charleston, South Carolina. With the exception of one Mediterranean Sea cruise, from 16 February to 26 June 1970, she continued to operate out of Charleston, along the Atlantic seaboard, in the Caribbean Sea, and in the Gulf of Mexico, until decommissioned 29 October 1973 at Charleston.

Greek service
After decommissioning from US Navy in 1973, she was transferred to the Hellenic Navy as a sale, and recommissioned Katsonis (S-115). She served until 31 March 1993, when she was decommissioned.

title: USS Remora


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Particle image velocimetry

Particle image velocimetry (PIV) is an optical method of flow visualization used in education and research. It is used to obtain instantaneous velocity measurements and related properties in fluids. The fluid is seeded with tracer particles which, for sufficiently small particles, are assumed to faithfully follow the flow dynamics (the degree to which the particles faithfully follow the flow is represented by the Stokes number). The fluid with entrained particles is illuminated so that particles are visible. The motion of the seeding particles is used to calculate speed and direction (the velocity field) of the flow being studied.

Other techniques used to measure flows are laser Doppler velocimetry and hot-wire anemometry. The main difference between PIV and those techniques is that PIV produces two-dimensional or even three-dimensional vector fields, while the other techniques measure the velocity at a point. During PIV, the particle concentration is such that it is possible to identify individual particles in an image, but not with certainty to track it between images. When the particle concentration is so low that it is possible to follow an individual particle it is called particle tracking velocimetry, while laser speckle velocimetry is used for cases where the particle concentration is so high that it is difficult to observe individual particles in an image.

Typical PIV apparatus consists of a camera (normally a digital camera with a charge-coupled device (CCD) chip in modern systems), a strobe or laser with an optical arrangement to limit the physical region illuminated (normally a cylindrical lens to convert a light beam to a line), a synchronizer to act as an external trigger for control of the camera and laser, the seeding particles and the fluid under investigation. A fiber-optic cable or liquid light guide may connect the laser to the lens setup. PIV software is used to post-process the optical images.

History
Particle image velocimetry (PIV) is a non-intrusive optical flow measurement technique used to study fluid flow patterns and velocities. PIV has found widespread applications in various fields of science and engineering, including aerodynamics, combustion, oceanography, and biofluids. The development of PIV can be traced back to the early 20th century when researchers started exploring different methods to visualize and measure fluid flow.

The early days of PIV can be credited to the pioneering work of Ludwig Prandtl, a German physicist and engineer, who is often regarded as the father of modern aerodynamics. In the 1920s, Prandtl and his colleagues used shadowgraph and schlieren techniques to visualize and measure flow patterns in wind tunnels. These methods relied on the refractive index differences between the fluid regions of interest and the surrounding medium to generate contrast in the images. However, these methods were limited to qualitative observations and did not provide quantitative velocity measurements.

The early PIV setups were relatively simple and used photographic film as the image recording medium. A laser was used to illuminate particles, such as oil droplets or smoke, added to the flow, and the resulting particle motion was captured on film. The films were then developed and analyzed to obtain flow velocity information. These early PIV systems had limited spatial resolution and were labor-intensive, but they provided valuable insights into fluid flow behavior.

The advent of lasers in the 1960s revolutionized the field of flow visualization and measurement. Lasers provided a coherent and monochromatic light source that could be easily focused and directed, making them ideal for optical flow diagnostics. In the late 1960s and early 1970s, researchers such as Arthur L. Lavoie, Hervé L. J. H. Scohier, and Adrian Fouriaux independently proposed the concept of particle image velocimetry (PIV). PIV was initially used for studying air flows and measuring wind velocities, but its applications soon extended to other areas of fluid dynamics.

In the 1980s, the development of charge-coupled devices (CCDs) and digital image processing techniques revolutionized PIV. CCD cameras replaced photographic film as the image recording medium, providing higher spatial resolution, faster data acquisition, and real-time processing capabilities. Digital image processing techniques allowed for accurate and automated analysis of the PIV images, greatly reducing the time and effort required for data analysis.

The advent of digital imaging and computer processing capabilities in the 1980s and 1990s revolutionized PIV, leading to the development of advanced PIV techniques, such as multi-frame PIV, stereo-PIV, and time-resolved PIV. These techniques allowed for higher accuracy, higher spatial and temporal resolution, and three-dimensional measurements, expanding the capabilities of PIV and enabling its application in more complex flow systems.

In the following decades, PIV continued to evolve and advance in several key areas. One significant advancement was the use of dual or multiple exposures in PIV, which allowed for the measurement of both instantaneous and time-averaged velocity fields. Dual-exposure PIV (often referred to as "stereo PIV" or "stereo-PIV") uses two cameras to capture two consecutive images with a known time delay, allowing for the measurement of three-component velocity vectors in a plane. This provided a more complete picture of the flow field and enabled the study of complex flows, such as turbulence and vortices.

In the 2000s and beyond, PIV continued to evolve with the development of high-power lasers, high-speed cameras, and advanced image analysis algorithms. These advancements have enabled PIV to be used in extreme conditions, such as high-speed flows, combustion systems, and microscale flows, opening up new frontiers for PIV research. PIV has also been integrated with other measurement techniques, such as temperature and concentration measurements, and has been used in emerging fields, such as microscale and nanoscale flows, granular flows, and additive manufacturing.

The advancement of PIV has been driven by the development of new laser sources, cameras, and image analysis techniques. Advances in laser technology have led to the use of high-power lasers, such as YAG lasers and diode lasers, which provide increased illumination intensity and allow for measurements in more challenging environments, such as high-speed flows and combustion systems. High-speed cameras with improved sensitivity and frame rates have also been developed, enabling the capture of transient flow phenomena with high temporal resolution. Furthermore, advanced image analysis techniques, such as correlation-based algorithms, phase-based methods, and machine learning algorithms, have been developed to enhance the accuracy and efficiency of PIV measurements.

Another major advancement in PIV was the development of digital correlation algorithms for image analysis. These algorithms allowed for more accurate and efficient processing of PIV images, enabling higher spatial resolution and faster data acquisition rates. Various correlation algorithms, such as cross-correlation, Fourier-transform-based correlation, and adaptive correlation, were developed and widely used in PIV research.

PIV has also benefited from the development of computational fluid dynamics (CFD) simulations, which have become powerful tools for predicting and analyzing fluid flow behavior. PIV data can be used to validate and calibrate CFD simulations, and in turn, CFD simulations can provide insights into the interpretation and analysis of PIV data. The combination of experimental PIV measurements and numerical simulations has enabled researchers to gain a deeper understanding of fluid flow phenomena and has led to new discoveries and advancements in various scientific and engineering fields.

In addition to the technical advancements, PIV has also been integrated with other measurement techniques, such as temperature and concentration measurements, to provide more comprehensive and multi-parameter flow measurements. For example, combining PIV with thermographic phosphors or laser-induced fluorescence allows for simultaneous measurement of velocity and temperature or concentration fields, providing valuable data for studying heat transfer, mixing, and chemical reactions in fluid flows.

Applications
The historical development of PIV has been driven by the need for accurate and non-intrusive flow measurements in various fields of science and engineering. The early years of PIV were marked by the development of basic PIV techniques, such as two-frame PIV, and the application of PIV in fundamental fluid dynamics research, primarily in academic settings. As PIV gained popularity, researchers started using it in more practical applications, such as aerodynamics, combustion, and oceanography.

As PIV continues to advance and evolve, it is expected to find further applications in a wide range of fields, from fundamental research in fluid dynamics to practical applications in engineering, environmental science, and medicine. The continued development of PIV techniques, including advancements in lasers, cameras, image analysis algorithms, and integration with other measurement techniques, will further enhance its capabilities and broaden its applications.

In aerodynamics, PIV has been used to study the flow over aircraft wings, rotor blades, and other aerodynamic surfaces, providing insights into the flow behavior and aerodynamic performance of these systems.

As PIV gained popularity, it found applications in a wide range of fields beyond aerodynamics, including combustion, oceanography, biofluids, and microscale flows. In combustion research, PIV has been used to study the details of combustion processes, such as flame propagation, ignition, and fuel spray dynamics, providing valuable insights into the complex interactions between fuel and air in combustion systems. In oceanography, PIV has been used to study the motion of water currents, waves, and turbulence, aiding in the understanding of ocean circulation patterns and coastal erosion. In biofluids research, PIV has been applied to study blood flow in arteries and veins, respiratory flow, and the motion of cilia and flagella in microorganisms, providing important information for understanding physiological processes and disease mechanisms.

PIV has also been used in new and emerging fields, such as microscale and nanoscale flows, granular flows, and multiphase flows. Micro-PIV and nano-PIV have been used to study flows in microchannels, nanopores, and biological systems at the microscale and nanoscale, providing insights into the unique behaviors of fluids at these length scales. PIV has been applied to study the motion of particles in granular flows, such as avalanches and landslides, and to investigate multiphase flows, such as bubbly flows and oil-water flows, which are important in environmental and industrial processes. In microscale flows, conventional measurement techniques are challenging to apply due to the small length scales involved. Micro-PIV has been used to study flows in microfluidic devices, such as lab-on-a-chip systems, and to investigate phenomena such as droplet formation, mixing, and cell motion, with applications in drug delivery, biomedical diagnostics, and microscale engineering.

PIV has also found applications in advanced manufacturing processes, such as additive manufacturing, where understanding and optimizing fluid flow behavior is critical for achieving high-quality and high-precision products. PIV has been used to study the flow dynamics of gases, liquids, and powders in additive manufacturing processes, providing insights into the process parameters that affect the quality and properties of the manufactured products.

PIV has also been used in environmental science to study the dispersion of pollutants in air and water, sediment transport in rivers and coastal areas, and the behavior of pollutants in natural and engineered systems. In energy research, PIV has been used to study the flow behavior in wind turbines, hydroelectric power plants, and combustion processes in engines and turbines, aiding in the development of more efficient and environmentally friendly energy systems.

Seeding particles
The seeding particles are an inherently critical component of the PIV system. Depending on the fluid under investigation, the particles must be able to match the fluid properties reasonably well. Otherwise they will not follow the flow satisfactorily enough for the PIV analysis to be considered accurate. Ideal particles will have the same density as the fluid system being used, and are spherical (these particles are called microspheres). While the actual particle choice is dependent on the nature of the fluid, generally for macro PIV investigations they are glass beads, polystyrene, polyethylene, aluminum flakes or oil droplets (if the fluid under investigation is a gas). Refractive index for the seeding particles should be different from the fluid which they are seeding, so that the laser sheet incident on the fluid flow will reflect off of the particles and be scattered towards the camera.

The particles are typically of a diameter in the order of 10 to 100 micrometers. As for sizing, the particles should be small enough so that response time of the particles to the motion of the fluid is reasonably short to accurately follow the flow, yet large enough to scatter a significant quantity of the incident laser light. For some experiments involving combustion, seeding particle size may be smaller, in the order of 1 micrometer, to avoid the quenching effect that the inert particles may have on flames. Due to the small size of the particles, the particles' motion is dominated by Stokes' drag and settling or rising effects. In a model where particles are modeled as spherical (microspheres) at a very low Reynolds number, the ability of the particles to follow the fluid's flow is inversely proportional to the difference in density between the particles and the fluid, and also inversely proportional to the square of their diameter. The scattered light from the particles is dominated by Mie scattering and so is also proportional to the square of the particles' diameters. Thus the particle size needs to be balanced to scatter enough light to accurately visualize all particles within the laser sheet plane, but small enough to accurately follow the flow.

The seeding mechanism needs to also be designed so as to seed the flow to a sufficient degree without overly disturbing the flow.

Camera
To perform PIV analysis on the flow, two exposures of laser light are required upon the camera from the flow. Originally, with the inability of cameras to capture multiple frames at high speeds, both exposures were captured on the same frame and this single frame was used to determine the flow. A process called autocorrelation was used for this analysis. However, as a result of autocorrelation the direction of the flow becomes unclear, as it is not clear which particle spots are from the first pulse and which are from the second pulse. Faster digital cameras using CCD or CMOS chips were developed since then that can capture two frames at high speed with a few hundred ns difference between the frames. This has allowed each exposure to be isolated on its own frame for more accurate cross-correlation analysis. The limitation of typical cameras is that this fast speed is limited to a pair of shots. This is because each pair of shots must be transferred to the computer before another pair of shots can be taken. Typical cameras can only take a pair of shots at a much slower speed. High speed CCD or CMOS cameras are available but are much more expensive.

Laser and optics
For macro PIV setups, lasers are predominant due to their ability to produce high-power light beams with short pulse durations. This yields short exposure times for each frame. YAG lasers, commonly used in PIV setups, emit primarily at 1064 nm wavelength and its harmonics (532, 266, etc.) For safety reasons, the laser emission is typically bandpass filtered to isolate the 532 nm harmonics (this is green light, the only harmonic able to be seen by the naked eye). A fiber-optic cable or liquid light guide might be used to direct the laser light to the experimental setup.

The optics consist of a spherical lens and cylindrical lens combination. The cylindrical lens expands the laser into a plane while the spherical lens compresses the plane into a thin sheet. This is critical as the PIV technique cannot generally measure motion normal to the laser sheet and so ideally this is eliminated by maintaining an entirely 2-dimensional laser sheet. The spherical lens cannot compress the laser sheet into an actual 2-dimensional plane. The minimum thickness is on the order of the wavelength of the laser light and occurs at a finite distance from the optics setup (the focal point of the spherical lens). This is the ideal location to place the analysis area of the experiment.

The correct lens for the camera should also be selected to properly focus on and visualize the particles within the investigation area.

Synchronizer
The synchronizer acts as an external trigger for both the camera(s) and the laser. While analogue systems in the form of a photosensor, rotating aperture and a light source have been used in the past, most systems in use today are digital. Controlled by a computer, the synchronizer can dictate the timing of each frame of the CCD camera's sequence in conjunction with the firing of the laser to within 1 ns precision. Thus the time between each pulse of the laser and the placement of the laser shot in reference to the camera's timing can be accurately controlled. Knowledge of this timing is critical as it is needed to determine the velocity of the fluid in the PIV analysis. Stand-alone electronic synchronizers, called digital delay generators, offer variable resolution timing from as low as 250 ps to as high as several ms. With up to eight channels of synchronized timing, they offer the means to control several flash lamps and Q-switches as well as provide for multiple camera exposures.

Analysis
The frames are split into a large number of interrogation areas, or windows. It is then possible to calculate a displacement vector for each window with help of signal processing and autocorrelation or cross-correlation techniques. This is converted to a velocity using the time between laser shots and the physical size of each pixel on the camera. The size of the interrogation window should be chosen to have at least 6 particles per window on average. A visual example of PIV analysis can be seen here.

The synchronizer controls the timing between image exposures and also permits image pairs to be acquired at various times along the flow. For accurate PIV analysis, it is ideal that the region of the flow that is of interest should display an average particle displacement of about 8 pixels. This is a compromise between a longer time spacing which would allow the particles to travel further between frames, making it harder to identify which interrogation window traveled to which point, and a shorter time spacing, which could make it overly difficult to identify any displacement within the flow.

The scattered light from each particle should be in the region of 2 to 4 pixels across on the image. If too large an area is recorded, particle image size drops and peak locking might occur with loss of sub pixel precision. There are methods to overcome the peak locking effect, but they require some additional work.

If there is in house PIV expertise and time to develop a system, even though it is not trivial, it is possible to build a custom PIV system. Research grade PIV systems do, however, have high power lasers and high end camera specifications for being able to take measurements with the broadest spectrum of experiments required in research.

An example of PIV analysis without installation:

PIV is closely related to digital image correlation, an optical displacement measurement technique that uses correlation techniques to study the deformation of solid materials.

Advantages
The method is, to a large degree, nonintrusive. The added tracers (if they are properly chosen) generally cause negligible distortion of the fluid flow.

Optical measurement avoids the need for Pitot tubes, hotwire anemometers or other intrusive Flow measurement probes. The method is capable of measuring an entire two-dimensional cross section (geometry) of the flow field simultaneously.

High speed data processing allows the generation of large numbers of image pairs which, on a personal computer may be analysed in real time or at a later time, and a high quantity of near-continuous information may be gained.

Sub pixel displacement values allow a high degree of accuracy, since each vector is the statistical average for many particles within a particular tile. Displacement can typically be accurate down to 10% of one pixel on the image plane.

Drawbacks
In some cases the particles will, due to their higher density, not perfectly follow the motion of the fluid (gas/liquid). If experiments are done in water, for instance, it is easily possible to find very cheap particles (e.g. plastic powder with a diameter of ~60 μm) with the same density as water. If the density still does not fit, the density of the fluid can be tuned by increasing/ decreasing its temperature. This leads to slight changes in the Reynolds number, so the fluid velocity or the size of the experimental object has to be changed to account for this.

Particle image velocimetry methods will in general not be able to measure components along the z-axis (towards to/away from the camera). These components might not only be missed, they might also introduce an interference in the data for the x/y-components caused by parallax. These problems do not exist in Stereoscopic PIV, which uses two cameras to measure all three velocity components.

Since the resulting velocity vectors are based on cross-correlating the intensity distributions over small areas of the flow, the resulting velocity field is a spatially averaged representation of the actual velocity field. This obviously has consequences for the accuracy of spatial derivatives of the velocity field, vorticity, and spatial correlation functions that are often derived from PIV velocity fields.

PIV systems used in research often use class IV lasers and high-resolution, high-speed cameras, which bring cost and safety constraints.

Stereoscopic PIV
Stereoscopic PIV utilises two cameras with separate viewing angles to extract the z-axis displacement. Both cameras must be focused on the same spot in the flow and must be properly calibrated to have the same point in focus.

In fundamental fluid mechanics, displacement within a unit time in the X, Y and Z directions are commonly defined by the variables U, V and W. As was previously described, basic PIV extracts the U and V displacements as functions of the in-plane X and Y directions. This enables calculations of the $$U_x$$, $$V_y$$, $$U_y$$ and $$V_x$$ velocity gradients. However, the other 5 terms of the velocity gradient tensor are unable to be found from this information. The stereoscopic PIV analysis also grants the Z-axis displacement component, W, within that plane. Not only does this grant the Z-axis velocity of the fluid at the plane of interest, but two more velocity gradient terms can be determined: $$W_x$$ and $$W_y$$. The velocity gradient components $$U_z$$, $$V_z$$, and $$W_z$$ can not be determined. The velocity gradient components form the tensor:

\begin{bmatrix} U_x & U_y & U_z \\ V_x & V_y & V_z \\ W_x & W_y & W_z \\ \end{bmatrix} $$

Dual plane stereoscopic PIV
This is an expansion of stereoscopic PIV by adding a second plane of investigation directly offset from the first one. Four cameras are required for this analysis. The two planes of laser light are created by splitting the laser emission with a beam splitter into two beams. Each beam is then polarized orthogonally with respect to one another. Next, they are transmitted through a set of optics and used to illuminate one of the two planes simultaneously.

The four cameras are paired into groups of two. Each pair focuses on one of the laser sheets in the same manner as single-plane stereoscopic PIV. Each of the four cameras has a polarizing filter designed to only let pass the polarized scattered light from the respective planes of interest. This essentially creates a system by which two separate stereoscopic PIV analysis setups are run simultaneously with only a minimal separation distance between the planes of interest.

This technique allows the determination of the three velocity gradient components single-plane stereoscopic PIV could not calculate: $$U_z$$, $$V_z$$, and $$W_z$$. With this technique, the entire velocity gradient tensor of the fluid at the 2-dimensional plane of interest can be quantified. A difficulty arises in that the laser sheets should be maintained close enough together so as to approximate a two-dimensional plane, yet offset enough that meaningful velocity gradients can be found in the z-direction.

Multi-plane stereoscopic PIV
There are several extensions of the dual-plane stereoscopic PIV idea available. There is an option to create several parallel laser sheets using a set of beamsplitters and quarter-wave plates, providing three or more planes, using a single laser unit and stereoscopic PIV setup, called XPIV.

Micro PIV
With the use of an epifluorescent microscope, microscopic flows can be analyzed. MicroPIV makes use of fluorescing particles that excite at a specific wavelength and emit at another wavelength. Laser light is reflected through a dichroic mirror, travels through an objective lens that focuses on the point of interest, and illuminates a regional volume. The emission from the particles, along with reflected laser light, shines back through the objective, the dichroic mirror and through an emission filter that blocks the laser light. Where PIV draws its 2-dimensional analysis properties from the planar nature of the laser sheet, microPIV utilizes the ability of the objective lens to focus on only one plane at a time, thus creating a 2-dimensional plane of viewable particles.

MicroPIV particles are on the order of several hundred nm in diameter, meaning they are extremely susceptible to Brownian motion. Thus, a special ensemble averaging analysis technique must be utilized for this technique. The cross-correlation of a series of basic PIV analyses are averaged together to determine the actual velocity field. Thus, only steady flows can be investigated. Special preprocessing techniques must also be utilized since the images tend to have a zero-displacement bias from background noise and low signal-noise ratios. Usually, high numerical aperture objectives are also used to capture the maximum emission light possible. Optic choice is also critical for the same reasons.

Holographic PIV
Holographic PIV (HPIV) encompasses a variety of experimental techniques which use the interference of coherent light scattered by a particle and a reference beam to encode information of the amplitude and phase of the scattered light incident on a sensor plane. This encoded information, known as a hologram, can then be used to reconstruct the original intensity field by illuminating the hologram with the original reference beam via optical methods or digital approximations. The intensity field is interrogated using 3-D cross-correlation techniques to yield a velocity field.

Off-axis HPIV uses separate beams to provide the object and reference waves. This setup is used to avoid speckle noise form being generated from interference of the two waves within the scattering medium, which would occur if they were both propagated through the medium. An off-axis experiment is a highly complex optical system comprising numerous optical elements, and the reader is referred to an example schematic in Sheng et al. for a more complete presentation.

In-line holography is another approach that provides some unique advantages for particle imaging. Perhaps the largest of these is the use of forward scattered light, which is orders of magnitude brighter than scattering oriented normal to the beam direction. Additionally, the optical setup of such systems is much simpler because the residual light does not need to be separated and recombined at a different location. The in-line configuration also provides a relatively easy extension to apply CCD sensors, creating a separate class of experiments known as digital in-line holography. The complexity of such setups shifts from the optical setup to image post-processing, which involves the use of simulated reference beams. Further discussion of these topics is beyond the scope of this article and is treated in Arroyo and Hinsch

A variety of issues degrade the quality of HPIV results. The first class of issues involves the reconstruction itself. In holography, the object wave of a particle is typically assumed to be spherical; however, due to Mie scattering theory, this wave is a complex shape which can distort the reconstructed particle. Another issue is the presence of substantial speckle noise which lowers the overall signal-to-noise ratio of particle images. This effect is of greater concern for in-line holographic systems because the reference beam is propagated through the volume along with the scattered object beam. Noise can also be introduced through impurities in the scattering medium, such as temperature variations and window blemishes. Because holography requires coherent imaging, these effects are much more severe than traditional imaging conditions. The combination of these factors increases the complexity of the correlation process. In particular, the speckle noise in an HPIV recording often prevents traditional image-based correlation methods from being used. Instead, single particle identification and correlation are implemented, which set limits on particle number density. A more comprehensive outline of these error sources is given in Meng et al.

In light of these issues, it may seem that HPIV is too complicated and error-prone to be used for flow measurements. However, many impressive results have been obtained with all holographic approaches. Svizher and Cohen used a hybrid HPIV system to study the physics of hairpin vortices. Tao et al. investigated the alignment of vorticity and strain rate tensors in high Reynolds number turbulence. As a final example, Sheng et al. used holographic microscopy to perform near-wall measurements of turbulent shear stress and velocity in turbulent boundary layers.

Scanning PIV
By using a rotating mirror, a high-speed camera and correcting for geometric changes, PIV can be performed nearly instantly on a set of planes throughout the flow field. Fluid properties between the planes can then be interpolated. Thus, a quasi-volumetric analysis can be performed on a target volume. Scanning PIV can be performed in conjunction with the other 2-dimensional PIV methods described to approximate a 3-dimensional volumetric analysis.

Tomographic PIV
Tomographic PIV is based on the illumination, recording, and reconstruction of tracer particles within a 3-D measurement volume. The technique uses several cameras to record simultaneous views of the illuminated volume, which is then reconstructed to yield a discretized 3-D intensity field. A pair of intensity fields are analyzed using 3-D cross-correlation algorithms to calculate the 3-D, 3-C velocity field within the volume. The technique was originally developed by Elsinga et al. in 2006.

The reconstruction procedure is a complex under-determined inverse problem. The primary complication is that a single set of views can result from a large number of 3-D volumes. Procedures to properly determine the unique volume from a set of views are the foundation for the field of tomography. In most Tomo-PIV experiments, the multiplicative algebraic reconstruction technique (MART) is used. The advantage of this pixel-by-pixel reconstruction technique is that it avoids the need to identify individual particles. Reconstructing the discretized 3-D intensity field is computationally intensive and, beyond MART, several developments have sought to significantly reduce this computational expense, for example the multiple line-of-sight simultaneous multiplicative algebraic reconstruction technique (MLOS-SMART) which takes advantage of the sparsity of the 3-D intensity field to reduce memory storage and calculation requirements.

As a rule of thumb, at least four cameras are needed for acceptable reconstruction accuracy, and best results are obtained when the cameras are placed at approximately 30 degrees normal to the measurement volume. Many additional factors are necessary to consider for a successful experiment.

Tomo-PIV has been applied to a broad range of flows. Examples include the structure of a turbulent boundary layer/shock wave interaction, the vorticity of a cylinder wake or pitching airfoil, rod-airfoil aeroacoustic experiments, and to measure small-scale, micro flows. More recently, Tomo-PIV has been used together with 3-D particle tracking velocimetry to understand predator-prey interactions, and portable version of Tomo-PIV has been used to study unique swimming organisms in Antarctica.

Thermographic PIV
Thermographic PIV is based on the use of thermographic phosphors as seeding particles. The use of these thermographic phosphors permits simultaneous measurement of velocity and temperature in a flow.

Thermographic phosphors consist of ceramic host materials doped with rare-earth or transition metal ions, which exhibit phosphorescence when they are illuminated with UV-light. The decay time and the spectra of this phosphorescence are temperature sensitive and offer two different methods to measure temperature. The decay time method consists on the fitting of the phosphorescence decay to an exponential function and is normally used in point measurements, although it has been demonstrated in surface measurements. The intensity ratio between two different spectral lines of the phosphorescence emission, tracked using spectral filters, is also temperature-dependent and can be employed for surface measurements.

The micrometre-sized phosphor particles used in thermographic PIV are seeded into the flow as a tracer and, after illumination with a thin laser light sheet, the temperature of the particles can be measured from the phosphorescence, normally using an intensity ratio technique. It is important that the particles are of small size so that not only they follow the flow satisfactorily but also they rapidly assume its temperature. For a diameter of 2 μm, the thermal slip between particle and gas is as small as the velocity slip.

Illumination of the phosphor is achieved using UV light. Most thermographic phosphors absorb light in a broad band in the UV and therefore can be excited using a YAG:Nd laser. Theoretically, the same light can be used both for PIV and temperature measurements, but this would mean that UV-sensitive cameras are needed. In practice, two different beams originated in separate lasers are overlapped. While one of the beams is used for velocity measurements, the other is used to measure the temperature.

The use of thermographic phosphors offers some advantageous features including ability to survive in reactive and high temperature environments, chemical stability and insensitivity of their phosphorescence emission to pressure and gas composition. In addition, thermographic phosphors emit light at different wavelengths, allowing spectral discrimination against excitation light and background.

Thermographic PIV has been demonstrated for time averaged and single shot measurements. Recently, also time-resolved high speed (3 kHz) measurements have been successfully performed.

Artificial Intelligence PIV
With the development of artificial intelligence, there have been scientific publications and commercial software proposing PIV calculations based on deep learning and convolutional neural networks. The methodology used stems mainly from optical flow neural networks popular in machine vision. A data set that includes particle images is generated to train the parameters of the networks. The result is a deep neural network for PIV which can provide estimation of dense motion, down to a maximum of one vector for one pixel if the recorded images allow. AI PIV promises a dense velocity field, not limited by the size of the interrogation window, which limits traditional PIV to one vector per 16 x 16 pixels.

Real time processing and applications of PIV
With the advance of digital technologies, real time processing and applications of PIV became possible. For instance, GPUs can be used to speed up substantially the direct of Fourier transform based correlations of single interrogation windows. Similarly multi-processing, parallel or multi-threading processes on several CPUs or multi-core CPUs are beneficial for the distributed processing of multiple interrogation windows or multiple images. Some of the applications use real time image processing methods, such as FPGA based on-the-fly image compression or image processing. More recently, the PIV real time measurement and processing capabilities are implemented for the future use in active flow control with the flow based feedback.

Applications
PIV has been applied to a wide range of flow problems, varying from the flow over an aircraft wing in a wind tunnel to vortex formation in prosthetic heart valves. 3-dimensional techniques have been sought to analyze turbulent flow and jets.

Rudimentary PIV algorithms based on cross-correlation can be implemented in a matter of hours, while more sophisticated algorithms may require a significant investment of time. Several open source implementations are available. Application of PIV in the US education system has been limited due to high price and safety concerns of industrial research grade PIV systems.

Granular PIV: velocity measurement in granular flows and avalanches
PIV can also be used to measure the velocity field of the free surface and basal boundary in a granular flows such as those in shaken containers, tumblers and avalanches. This analysis is particularly well-suited for nontransparent media such as sand, gravel, quartz, or other granular materials that are common in geophysics. This PIV approach is called "granular PIV". The set-up for granular PIV differs from the usual PIV setup in that the optical surface structure which is produced by illumination of the surface of the granular flow is already sufficient to detect the motion. This means one does not need to add tracer particles in the bulk material.

title: Particle image velocimetry


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USS Sirago

USS Sirago (SS-485), a Tench-class submarine, was named for the sirago, a small, freshwater tropical fish.

Construction and launch
Her keel was laid down on 4 January 1945 at the Portsmouth Navy Yard in Kittery, Maine. She was launched on 13 May 1945, sponsored by Mrs. L. Mendel Rivers and commissioned on 13 August 1945 with Commander F. J. Harlfinger II, in command.

First duties
Commissioned at the end of World War II, Sirago conducted her shakedown cruise off the East Coast and in the Caribbean Sea during the fall of 1945. After shakedown, she joined Submarine Squadron (SubRon) 8 at New London, Connecticut, and, in January 1946, she proceeded to Provincetown, Massachusetts, where she participated in the destruction of U-Boats U-1228, and U-805 off of Cape Cod, Massachusetts on 5 February and 8, later sinking U-858 as well on 21 November 1947. On returning to New London, Sirago commenced duties that included training services for the Submarine School and for the fleet's destroyer force; experimental exercises to evaluate new techniques and equipment; type training; and fleet exercises that took her from Davis Strait into the Caribbean. In December 1948, she entered the Philadelphia Naval Shipyard for a Greater Underwater Propulsive Power Program (GUPPY) conversion; and, on 25 July 1949, she left the yard for Norfolk, Virginia, where, as a modernized high-speed attack submarine, she joined SubRon 6.

Attached to SubRon 6 for the next twenty-two years, Sirago’s primary mission was antisubmarine warfare. Secondary missions included antishipping warfare, intelligence gathering, and the provision of services for research and development studies. Those duties, during the 1950s, continued to see her operating primarily in the western Atlantic as she participated in exercises with others of her ASW group; in fleet exercises; in joint Canadian-United States exercises, and in NATO exercises, which took her into the eastern Atlantic Ocean and North Sea areas. During the 1950s, she also deployed to the Mediterranean Sea where she operated as a unit of the Sixth Fleet from September to November 1951 and from September to December 1954.

Fatal accident
An explosion aboard Sirago while drydocked at Portsmouth, New Hampshire, on 2 June 1954, killed two men and injured four others. The blast, which occurred during plastic spraying of a main ballast tank, killed two civilian painters and injured a sailor and three other civilian painters. The burst was heard three miles away.

Overhaul and new service
In October 1962, Sirago entered the Norfolk Naval Shipyard for another extensive overhaul which included the installation of a fiberglass superstructure and sail and, in the spring of 1963, she resumed operations with her ASW group, Task Group "ALFA." That fall, she deployed to the Middle East for CENTO exercise "MIDLINK VI"; but, during the remainder of the 1960s and into the 1970s, her operations were similar to those of the 1950s.

On 1 July 1971, with Commander Clyde H. Shaffer Jr. in command, Sirago was reassigned to SubRon 12 at Key West, Florida; but, less than four months later, on 15 October, she was ordered back to Norfolk, where she rejoined SubRon 6 for one more year.

Decommissioning
Sirago remained in SubRon 6 until she was decommissioned on 1 June 1972. Struck from the Naval Vessel Register on the same day, she was turned over to the Naval Ships Systems Command and sold for scrapping to the Jacobson Metal Company of Chesapeake, Virginia, on 2 May 1973.

title: USS Sirago


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USS Odax

USS Odax (SS-484), a Tench-class submarine, was the only ship of the United States Navy to be named for odax, a brilliantly colored, red and green fish belonging to the family Scaridae, the parrot fishes.

Construction and commissioning
Odax′s keel was laid down by the Portsmouth Navy Yard at Kittery, Maine, on 4 December 1944. She was launched on 10 April 1945, sponsored by Mrs. Luise Fogarty, wife of Rhode Island Congressman John E. Fogarty, and commissioned on 11 July 1945.

1940s
After shakedown off Portsmouth, New Hampshire, Odax got underway 19 September 1945 for Guantanamo Bay Naval Base in Cuba to provide services to the Fleet Training Group. On 30 October 1945, she departed for Key West, Florida, for duty with the Fleet Sonar School and conducted operational training until September 1946.

In September 1946, as part of the Bureau of Ships post-war investigation of the high-speed submarine, Odax was selected for conversion to a Greater Underwater Propulsive Power Program (GUPPY) submarine and returned to the Portsmouth Navy Yard. Completing conversion in August 1947, the first of the GUPPY submarines, she departed for Key West for extensive research development work.

1950s
In August 1951, Odax again arrived at the Portsmouth Navy Yard for conversion. The major aspect was the addition of a snorkel and redesignation as a GUPPY II submarine. She first put her snorkel to tactical use in a large-scale convoy exercise in the spring of 1952.

From 1952 through 1955, Odax provided services to the Operational Development Force and Fleet Sonar School in Key West and to the Fleet Training Group in Guantanamo Bay. During 1956 she received new equipment of improved design at the Charleston Naval Shipyard and departed in December, bound for the North Atlantic, to operate with the British Fleet. Subsequent operations in 1957 included services to the Operational Development Force, training submariners in the latest tactics of undersea warfare.

In September 1958, Odax deployed to the Mediterranean Sea for a tour with the Sixth Fleet. During this deployment she transited the Suez Canal to participate in a Baghdad Pact exercise in the Arabian Sea.

After her return home, Odax changed home port transferring to Charleston, South Carolina, in February 1959. She sailed from here early in 1960 to return to the North Atlantic for Barrier Patrol.

1960s
Odax departed Charleston, South Carolina in August 1960 for South America to conduct exercises with naval units of various South American countries during Exercise UNITAS. In December, she returned to Charleston to resume local operations.

Between 1961 and 1964, Odax conducted training operations out of Charleston with interim periods for overhaul and modernization.

In August 1964, she deployed again to South America to participate in combined operations while circumnavigating the continent, returning in December. From 1965 to 1967 she operated out of Charleston.

In May 1967, Odax began a deployment in Northern Europe. Upon her return to Charleston she was awarded the coveted Battle Efficiency "E" for Fiscal Year 1967. She resumed coastal operations in October 1967.

In October and November 1967, Odax provided services to the Fleet Training Group in Guantanamo Bay, Cuba for a period of 8 weeks.

In February 1968, Odax entered the Charleston Naval Shipyard for overhaul and upon completion in September operated in the Charleston area.

In January 1969, Odax participated in fleet operations in the Caribbean.

In March 1969, Odax deployed to the Mediterranean Sea for NATO operations.

In August 1969, Odax conducted training operations in the local Charleston area.

1970s and transfer to Brazilian Navy
In May 1970, Odax departed Charleston for northern Europe for a five-month NATO exercise. During this deployment, while submerged in the Norwegian Sea, Odax learned that her home port had been changed to Key West, Florida.

In December 1970, Odax was awarded the Navy Unit Commendation for her participation in the NATO operations in Northern Europe. The ship was also awarded her second Battle Efficiency "E".

During 1971, Odax participated in extensive tests of the new SQS-26 sonar system. Early in the year she took time out to visit New Orleans for Mardi Gras, and to submerge in the Mississippi River for publicity purposes.

In August 1971, Odax went to Guantanamo Bay, Cuba to provide services for US and NATO training exercises.

In February 1972, Odax again provided publicity services by submerging in the Mississippi River in downtown New Orleans during Mardi Gras.

In March and April 1972, in her last military duty, Odax provided NATO services during a seven-week unsupported deployment to the Eastern Atlantic.

On 8 July 1972, Odax was stricken from the Naval Vessel Register and transferred to Brazil. Commissioned into the Marinha do Brasil as Rio de Janeiro (S-13), she was decommissioned in 1978 and broken up in 1981.

title: USS Odax


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Multipurpose community telecenters

Multipurpose Community Telecenters are telecentre facilities, which provide public access to a variety of communication and information services, such as libraries and seminar rooms. They are promoted by many governments and organisations including the International Telecommunication Union. They are generally introduced to try to bring access to information and communication technologies in rural communities, but often find significant obstacles in the high cost of connectivity, low digital literacy in the community and high maintenance costs, and are thus forced to shut down. Out of 23 of the MCT's built in rural Mexico, only 5 were working 2 years later.

title: Multipurpose community telecenters


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Wikipedia:Articles for deletion/Buddhala

Buddhala
Joke. As can be checked on Google, every word in the article is spurious. The author was active vandalazing (see his history at Special:Contributions/66.210.50.50, e.g. replacing "Constantinople" by "Buddhala" in the Istambul entry of the Wikipedia). --French Tourist 19:15, 11 Oct 2004 (UTC) As a practicing Buddhist, I can vouch for the authenticity of this information. Granted, most of it is obscure, but that does not qualify it as a "hoax." (66.210.50.50)
 * Speedy deleted, and then recreated. Delete. Geogre 22:17, 11 Oct 2004 (UTC)
 * That's the worst misspelling of Siddhartha Gautama I've ever seen. Delete. --Aponar Kestrel (talk) 01:30, 2004 Oct 12 (UTC)
 * Mildly amusing hoax, Delete. One of the side effects of years of VfD entries will eventually be to teach people how to perpetrate hoaxes: the survival of the fittest ones. I wonder how many hoaxes have made it past us. — Bill 13:33, 12 Oct 2004 (UTC)
 * Note that the same one who wrote the above vandalized Gautama Buddha. andy 17:42, 13 Oct 2004 (UTC)

Attempting to delete this page seems like a ribald act of racism, imo. Unfortunately, articles extolling the virtues of white anglo-saxon culture are not the ONLY articles welcome on an open wiki; we need to learn to appreciate the diversity that this internet community affords us. This includes articles that we may find unusual, surprising, or even "jokes" (as one member implies above). Please do not delete this cross-cultural reference point from our Wiki community. Thanks! - Unregistered User (198.81.26.41)

 * Note that somebody using the same AOL IP address than this "Unregistered User" vandalized Harrison Bergeron four minutes after the previous comment was added. --French Tourist 13:39, 14 Oct 2004 (UTC)

Hi French Tourist, This is the "unregistered user" who posted above. Unfortunately, IP addresses can be shared by multiple users. I did not vandalize the Harrison Bergeron page, although that happens to be one of my favorite Kurt Vonnegut stories ;) (198.81.26.41)

 * Delete... all sock puppets. func(talk) 03:57, 15 Oct 2004 (UTC)
 * Delete likely prank. Fire Star 21:14, 15 Oct 2004 (UTC)

Note: anon 198.81.26.41 just vandalized this page. I think it is reasonable to assume/guess that 198.81.26.41 and 66.210.50.50 are one in the same vandal. func(talk) 03:42, 17 Oct 2004 (UTC)


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Francisco Suárez

Francisco Suárez, (5 January 1548 – 25 September 1617) was a Spanish Jesuit priest, philosopher and theologian, one of the leading figures of the School of Salamanca movement. His work is considered a turning point in the history of second scholasticism, marking the transition from its Renaissance to its Baroque phases. According to Christopher Shields and Daniel Schwartz, "figures as distinct from one another in place, time, and philosophical orientation as Leibniz, Grotius, Pufendorf, Schopenhauer and Heidegger, all found reason to cite him as a source of inspiration and influence."

Life and career
Francisco Suárez was born in Granada, Andalusia (southern Spain), on 5 January 1548. He was the youngest son of a noble family formed by the lawyer Gaspar Suárez de Toledo and his wife Antonia Vázquez de Utiel.

After 3 years of preliminary studies from age 10 onwards, in 1561 Suárez matriculated at the University of Salamanca, and studied law. In 1564, at age sixteen, Suárez entered the Society of Jesus in Salamanca and went through the two years of intense spiritual training under the guidance of Fr. Alonso Rodriguez. In August 1566, Suárez took his first vows as a Jesuit; he then began in October 1566 to study Theology at Salamanca. It seems he was not a promising student at first; in fact, he nearly gave up his matters of study after failing the entrance exam twice. After passing the exam at third attempt, though, things changed.

In 1570, with the completion of his course, Suárez began to teach Philosophy, first at Salamanca as a Scholastic tutor, and then as a professor in the Jesuit college at Segovia. He was ordained in March 1572 in Segovia. He continued to teach Philosophy in Segovia until, in September 1574, he moved to the Jesuit College in Valladolid to teach Theology, a subject he would then teach for the rest of his life. He taught in a succession of different places: Ávila (1575), Segovia (1575), Valladolid (1576) Rome (1580–85), Alcalá (1585–92) and Salamanca (1592–97). In 1597, he moved to Coimbra, some years after the accession of the Spanish (elder line) House of Habsburg to the Portuguese Throne, to take up the principal chair of Theology at the University of Coimbra. He remained there, aside from a brief time teaching at Rome, until his death in 1617.

He wrote on a wide variety of subjects, producing a vast amount of work (his complete works in Latin amount to twenty-six volumes). Suárez's writings include treatises on law, the relationship between Church and State, metaphysics, and theology. He is considered the godfather of International Law. His Disputationes metaphysicae (Metaphysical Disputations) were widely read in Europe during the 17th century and are considered by some scholars to be his most profound work.

Suárez was regarded during his lifetime as being the greatest living philosopher and theologian, and given the nickname Doctor Eximius et Pius ("Exceptional and Pious Doctor"); Pope Gregory XIII attended his first lecture in Rome. Pope Paul V invited him to refute the arguments of James I of England, and wished to retain him near his person, to profit by his knowledge. Philip II of Spain sent him to the University of Coimbra in order to give it prestige, and when Suárez visited the University of Barcelona, the doctors of the university went out to meet him wearing the insignia of their faculties.

After his death in Portugal (in either Lisbon or Coimbra) his reputation grew still greater, and he had a direct influence on such leading philosophers as Hugo Grotius, René Descartes, John Norris, and Gottfried Leibniz. He is buried in the Igreja de São Roque (formerly a Jesuit church) in Lisbon.

In 1679 Pope Innocent XI publicly condemned sixty-five casuist propositions, taken chiefly from the writings of Escobar, Suárez and others, mostly Jesuit, theologians as propositiones laxorum moralistarum and forbade anyone to teach them under penalty of excommunication.

Philosophical thought
His most important philosophical achievements were in metaphysics and the philosophy of law. Suárez may be considered the last eminent representative of scholasticism. He adhered to a moderate form of Thomism and developed metaphysics as a systematic enquiry.

Metaphysics
For Suárez, metaphysics was the science of real essences (and existence); it was mostly concerned with real being rather than conceptual being, and with immaterial rather than with material being. He held (along with earlier scholastics) that essence and existence are the same in the case of God (see ontological argument), but disagreed with Aquinas and others that the essence and existence of finite beings are really distinct. He argued that in fact they are merely conceptually distinct: rather than being really separable, they can only logically be conceived as separate.

On the vexed subject of universals, he endeavored to steer a middle course between the realism of Duns Scotus and the nominalism of William of Occam. His position is a little bit closer to nominalism than that of Thomas Aquinas. Sometimes he is classified as a moderate nominalist, but his admitting of objective precision (praecisio obiectiva) ranks him with moderate realists. The only veritable and real unity in the world of existences is the individual; to assert that the universal exists separately ex parte rei would be to reduce individuals to mere accidents of one indivisible form. Suárez maintains that, though the humanity of Socrates does not differ from that of Plato, yet they do not constitute realiter one and the same humanity; there are as many "formal unities" (in this case, humanities) as there are individuals, and these individuals do not constitute a factual, but only an essential or ideal unity ("In such a way, that many individuals, which are said to be of the same nature, are so: only through the operation of the intellect, not through a substance or essence of things which unites them"). The formal unity, however, is not an arbitrary creation of the mind, but exists "in the nature of the thing, prior [ontologically] to any operation of the intellect".

His metaphysical work, giving a remarkable effort of systematisation, is a real history of medieval thought, combining the three schools available at that time: Thomism, Scotism and Nominalism. He is also a deep commentator of Arabic or high medieval works. He enjoyed the reputation of being the greatest metaphysician of his time. He thus founded a school of his own, Suarism or Suarezianism, the chief characteristic principles of which are:
 * the principle of individuation by the proper concrete entity of beings
 * the rejection of pure potentiality of matter
 * the singular as the object of direct intellectual cognition
 * a distinctio rationis ratiocinatae between the essence and the existence of created beings
 * the possibility of spiritual substance only numerically distinct from one another
 * ambition for the hypostatic union as the sin of the fallen angels
 * the Incarnation of the Word, even if Adam had not sinned
 * the solemnity of the vow only in ecclesiastical law
 * the system of Congruism that modifies Molinism by the introduction of subjective circumstances, as well as of place and of time, propitious to the action of efficacious grace, and with predestination ante praevisa merita
 * the possibility of holding one and the same truth by both science and faith
 * the belief in Divine authority contained in an act of faith
 * the production of the body and blood of Christ by transubstantiation as constituting the Eucharistic sacrifice
 * the final grace of the Blessed Virgin Mary superior to that of the angels and saints combined.

Suárez made an important investigation of being, its properties and division in Disputationes Metaphysicae (1597), which influenced the further development of theology within Catholicism. In the second part of the book, disputations 28–53, Suárez fixes the distinction between ens infinitum (God) and ens finitum (created beings). The first division of being is that between ens infinitum and ens finitum. Instead of dividing being into infinite and finite, it can also be divided into ens a se and ens ab alio, i.e., being that is from itself and being that is from another. A second distinction corresponding to this one:ens necessarium and ens contingens, i.e., necessary being and contingent being. Still another formulation of the distinction is between ens per essentiam and ens per participationem, i.e., being that exists by reason of its essence and being that exists only by participation in a being that exists on its own (eigentlich). This distinction had just been formerly adopted by St. Thomas Aquinas in his Summa Theologica. A further distinction is between ens increatum and ens creatum, i.e., uncreated being and created, or creaturely, being. A final distinction is between being as actus purus and being as ens potentiale, i.e., being as pure actuality and being as potential being. Suárez decided in favor of the first classification of the being into ens infinitum and ens finitum as the most fundamental, in connection with which he accords the other classifications their due. In the last disputation 54 Suárez deals with entia rationis (beings of reason), which are impossible intentional objects, i.e. objects that are created by our minds but cannot exist in actual reality.

Theology
In theology, Suárez attached himself to the doctrine of Luis Molina, the celebrated Jesuit professor of Évora. Molina tried to reconcile the doctrine of predestination with the freedom of the human will and the predestinarian teachings of the Dominicans by saying that the predestination is consequent upon God's foreknowledge of the free determination of man's will, which is therefore in no way affected by the fact of such predestination. Suárez endeavoured to reconcile this view with the more orthodox doctrines of the efficacy of grace and special election, maintaining that, though all share in an absolutely sufficient grace, there is granted to the elect a grace which is so adapted to their peculiar dispositions and circumstances that they infallibly, though at the same time quite freely, yield themselves to its influence. This mediatizing system was known by the name of "congruism."

Philosophy of law
Here, Suárez's main importance stems probably from his work on natural law, and from his arguments concerning positive law and the status of a monarch. In his massive work, Tractatus de legibus ac deo legislatore (1612), he is to some extent the precursor of Grotius and Pufendorf, in making an important distinction between natural law and international law, which he saw as based on custom. Though his method is throughout scholastic, he covers the same ground, and Grotius speaks of him with great respect. The fundamental position of the work is that all legislative as well as all paternal power is derived from God, and that the authority of every law stems ultimately from God's eternal law. Suárez denies the patriarchal theory of government and the divine right of kings founded upon it, doctrines popular at that time in England and to some extent on the Continent. He argued against the sort of social contract theory that became dominant among early-modern political philosophers such as Thomas Hobbes and John Locke, but some of his thinking, as transmitted by Grotius, found echoes in later liberal political theory.

He argued that human beings have a social nature bestowed upon them by God, and this includes the potential to make laws. However, when a political society is formed, the authority of the state is not of divine but of human origin; therefore, its nature is chosen by the people involved, and their natural legislative power is given to the ruler. Because they gave this power, they have the right to take it back and to revolt against a ruler, only if the ruler behaves badly towards them, and they must act moderately and justly. In particular, the people must refrain from killing the ruler, no matter how tyrannical he may have become. If a government is imposed on people, on the other hand, they have the right to defend themselves by revolting against it and even kill the tyrannical ruler.

Though Suárez was greatly influenced by Aquinas in his philosophy of law, there are some notable differences. Aquinas broadly defined "law" as "a rule and measure acts, whereby man is induced to act or is restrained from acting" (ST 1-11, qu. 90, art. 1). Suárez argues that this definition is too broad, since it applies to things that are not strictly laws, such as unjust ordinances and counsels of perfection. Suárez also takes issue with Aquinas' more formal definition of "law" as "an ordinance of reason for the common good, made by him who has care of the community, and promulgated" (ST 1-11, qu. 90, art. 4). This definition, he claims, fails to recognize that law is primarily an act of will rather than an act of reason, and would wrongly count orders to particular individuals as being laws. Finally, Suárez disagrees with Aquinas's claim that God can change or suspend some of the secondary precepts of the natural law, such as the prohibitions on murder, theft, and adultery (ST 1-11, qu. 94, art. 5). Suárez argues that the natural law is immutable as long as human nature remains unchanged, and that what may appear to be divinely-made changes in the natural law are really just alterations of subject matter. For example, when God orders Hosea to take a "wife of fornications" (i.e., have sex with a prostitute), this is not an exemption from God's prohibition of adultery. "For God has power to transfer to a man dominium over a woman without her consent, and to effect such a bond between them that, by virtue of this bond, the union is no longer one of fornication."

In 1613, at the instigation of Pope Paul V, Suárez wrote a treatise dedicated to the Christian princes of Europe, entitled Defensio catholicae fidei contra anglicanae sectae errores ("Defense of the Universal Catholic Faith Against the Errors of the Anglican Sect"). This was directed against the oath of allegiance which James I required from his subjects.

James (himself a talented scholar) caused it to be burned by the common hangman and forbade its perusal under the 'severest penalties, complaining bitterly to Philip III of Spain for harbouring in his dominions a declared enemy of the throne and majesty of kings.

Influence
The contributions of Suarez to metaphysics and theology exerted significant influence over 17th and 18th century scholastic theology among both Roman Catholics and Protestants.

Thanks in part to the strength of Suárez's Jesuit order, his Disputationes Metaphysicae was widely taught in the Catholic schools of Spain, Portugal and Italy.

It also spread from these schools to many Lutheran universities in Germany, where the text was studied especially by those who favoured Melanchthon rather than Luther's attitude towards philosophy. In a number of seventeenth-century Lutheran universities the Disputationes served as a textbook in philosophy.

In a similar way, Suárez had major influence in the Reformed tradition of German and Dutch schools for both metaphysics and law, including international law. His work was highly praised, for example, by Hugo Grotius (1583-1645).

His influence is evident in the writings of Bartholomaeus Keckermann (1571–1609), Clemens Timpler (1563–1624), Gilbertus Jacchaeus (1578–1628), Johann Heinrich Alsted (1588–1638), Antonius Walaeus (1573–1639), and Johannes Maccovius (Jan Makowski; 1588–1644), among others. This influence was so pervasive that by 1643 it provoked the Dutch Reformed theologian Jacobus Revius to publish his book-length response: Suarez repurgatus. Suárez's De legibus was cited as among the best books on law by the Puritan Richard Baxter, and Baxter's friend Matthew Hale drew on it for his natural-law theory.

Criticism
The views of Suarez upon the human origin of political order, and his defense of tyrannicide emanating from popular dissent were heavily criticized by English philosopher Robert Filmer in his work Patriarcha, Or the Natural Power of Kings. Filmer believed Calvinists and Catholics like Suarez to be dangerous opponents of divine right monarchy, legitimized by the supremacy of fathers upon their offspring, which Filmer claimed could be traced back to Adam.

Main work

 * De Incarnatione (1590–1592)
 * De sacramentis (1593–1603)
 * Disputationes metaphysicae (1597)
 * De divina substantia eiusque attributis (1606)
 * De divina praedestinatione et reprobatione (1606)
 * De sanctissimo Trinitatis mysterio (1606)
 * De religione (1608–1625)
 * De legibus (1612)
 * Defensio fidei (1613)
 * De gratia (1619)
 * De angelis (1620)
 * De opere sex dierum (1621)
 * De anima (1621)
 * De fide, spe et caritate (1622)
 * De ultimo fine hominis (1628)

In the 18th century, the Venice edition of Opera Omnia in 23 volumes in folio (1740–1751) appeared, followed by the Parisian Vivès edition, 26 volumes + 2 volumes of indices (1856–1861); in 1965 the Vivés edition of the Disputationes Metaphysicae (vols. 25–26) was reprinted by Georg Olms, Hildesheim.

From 1597 to 1636 the Disputationes Metaphysicae were published in seventeen editions; no modern edition of Suárez's complete works is yet available and only few of Suárez's Disputations have been translated into English.

title: Francisco Suárez