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Lakota language

Lakota (Lakȟótiyapi ), also referred to as Lakhota, Teton or Teton Sioux, is a Siouan language spoken by the Lakota people of the Sioux tribes. Lakota is mutually intelligible with the two dialects of the Dakota language, especially Western Dakota, and is one of the three major varieties of the Sioux language.

Speakers of the Lakota language make up one of the largest Native American language speech communities in the United States, with approximately 2,000 speakers, who live mostly in the northern plains states of North Dakota and South Dakota. Many communities have immersion programs for both children and adults.

Like many indigenous languages, the Lakota language did not have a written form traditionally. However, efforts to develop a written form of Lakota began, primarily through the work of Christian missionaries and linguists, in the late 19th and early 20th centuries. The orthography has since evolved to reflect contemporary needs and usage.

One significant figure in the development of a written form of Lakota was Dr. Ella Cara Deloria, also called Aŋpétu Wašté Wiŋ (Beautiful Day Woman), a Yankton Dakota ethnologist, linguist, and novelist who worked extensively with the Dakota and Lakota peoples, documenting their languages and cultures. She collaborated with linguists such as Franz Boas and Edward Sapir to create written materials for Lakota, including dictionaries and grammars.

Another key figure was Albert White Hat Sr., who taught at and later became the chair of the Lakota language program at his alma mater, Sinte Gleska University at Mission, South Dakota, one of the first tribal-based universities in the US. His work focused on the Sicangu dialect using an orthography developed by Lakota in 1982 and which today is slowly supplanting older systems provided by linguists and missionaries.

History and origin
The Lakota people's creation stories say that language originated from the creation of the tribe. Other creation stories say language was invented by Iktomi.

Vowels
Lakota has five oral vowels,, and three nasal vowels, (phonetically ). Lakota and  are said to be more open than the corresponding cardinal vowels, perhaps closer to  and. Orthographically, the nasal vowels are written with a following $\langleƞ\rangle$, $\langleŋ\rangle$, or $\langlen\rangle$; historically, these were written with ogoneks underneath, $\langleį ą ų\rangle$. No syllables end with consonantal.

A neutral vowel (schwa) is automatically inserted between certain consonants, e.g. into the pairs $⟨i⟩$, $⟨u⟩$ and $⟨iŋ⟩$. So the clan name written phonemically as $⟨uŋ⟩$ has become the place name Ogallala.

Consonants
The voiced uvular fricative becomes a uvular trill  before  and in fast speech it is often realized as a voiced velar fricative. The voiceless aspirated plosives have two allophonic variants each: those with a delay in voicing, and those with velar friction , which occur before , , , , and (thus, lakhóta,  is phonetically ). For some speakers, there is a phonemic distinction between the two, and both occur before. No such variation occurs for the affricate /tʃʰ/. Some orthographies mark this distinction; others do not. The uvular fricatives and  are commonly spelled $⟨e⟩$ and $⟨o⟩$.

All monomorphemic words have one vowel which carries primary stress and has a higher tone than all other vowels in the word. This is generally the vowel of the second syllable of the word, but often the first syllable can be stressed, and occasionally other syllables as well. Stress is generally indicated with an acute accent: $⟨a⟩$, etc. Compound words will have stressed vowels in each component; proper spelling will write compounds with a hyphen. Thus máza-ská, literally "metal-white", i.e. "silver; money" has two stressed vowels, the first a in each component. If it were written without the hyphen, as mazaska, it would imply a single main stress.

Phonological processes
A common phonological process which occurs in rapid speech is vowel contraction, which generally results from the loss of an intervocalic glide. Vowel contraction results in phonetic long vowels (phonemically a sequence of two identical vowels), with falling pitch if the first underlying vowel is stressed, and rising pitch if the second underlying vowel is stressed: kê: (falling tone), "he said that", from kéye; hǎ:pi (rising tone), "clothing", from hayápi. If one of the vowels is nasalized, the resulting long vowel is also nasalized: čhaŋ̌:pi, "sugar", from čhaŋháŋpi.

When two vowels of unequal height contract, or when feature contrasts exist between the vowels and the glide, two new phonetic vowels, and, result: iyæ̂:, "he left for there", from iyáye; mitȟa:, "it's mine", from mitȟáwa.

The plural enclitic =pi is frequently changed in rapid speech when preceding the enclitics =kte, =kiŋ, =kštó, or =na. If the vowel preceding =pi is high/open, =pi becomes [u]; if the vowel is non-high (mid or closed), =pi becomes [o] (if the preceding vowel is nasalized, then the resulting vowel is also nasalized): hi=pi=kte, "they will arrive here", [hiukte]; yatkáŋ=pi=na, "they drank it and...",.

Lakota also exhibits some traces of sound symbolism among fricatives, where the point of articulation changes to reflect intensity: zí, "it's yellow", ží, "it's tawny", ǧí, "it's brown". (Compare with the similar examples in Mandan.)

Orthographies, standardization, and teaching materials
Several orthographies as well as ad hoc spelling are used to write the Lakota language, with varying perspectives on whether standardization should be implemented. In 2002, Rosebud Cultural Studies teacher Randy Emery argued that standardization of the language could cause problems "because the language is utilized diversely. If standardization is determined to be the approach... then the question is whose version will be adopted? This will cause dissent and politics to become a factor in the process."

Also in 2002, Sinte Gleska University rejected a partnership with the European-owned Lakota Language Consortium. Sinte Gleska uses the orthography developed by Albert White Hat, which on December 13, 2012, was formally adopted by the Rosebud Sioux Tribe per Tribal Resolution No. 2012–343. This resolution also banned the Lakota Language Consortium and its "Czech orthography" from the reservation and its educational system. This ban was a response to a series of protests by community members and grassroots language preservation workers, at Rosebud and other Lakota communities, against the Lakota Language Consortium (LLC). Despite its name, the LLC is an organization formed by two Europeans. Concerns arose due to the LLC's promotion of their New Lakota Dictionary, websites and other Internet projects aimed at revising and standardizing their new spelling of the Lakota language. "Lakota first language speakers and Lakota language teachers criticize the "Czech orthography" for being overloaded with markings and – foremost – for the way it is being brought into Lakota schools"; it has been criticized as "neocolonial domination." Sonja John writes that "The new orthography the Czech linguist advocates resembles the Czech orthography – making it easier for Czech people to read. The Europeans predominantly use the internet to give the impression that this "Czech orthography" is a Lakota product and the standard for writing Lakota." "The Rosebud Sioux Tribe was the first of the Lakota tribes to take legal action against the self-authorizing practices the LLC committed by utilizing names of Lakota language experts without their consent to obtain funding for their projects." Rosebud Resolution No. 2008–295 goes further and compares these actions to what was done to children taken from their families by the residential schools.

In 2006 some of the Lakota language teachers at Standing Rock chose to collaborate with Sitting Bull College, and the Lakota Language Consortium (LLC), with the aim of expanding their language curriculum. Teachers at Standing Rock use several different orthographies. Language activists at Standing Rock also refer to it as simply the "SLO" or even "Suggested Lakota Orthography." Tasha Hauff writes, "Choosing a writing system, or orthography, is often a serious point of contention in Indigenous communities engaging in revitalization work (Hinton, 2014). While writing a traditionally oral language can itself be considered a colonial act, standardizing a writing system is fraught with political as well as pedagogical complications. Because teachers at Standing Rock were in need of language-teaching materials, and the LLC was one of the few organizations developing such resources, Standing Rock adopted the new orthography, but not without resistance from members of the community. ... The new writing system at Standing Rock was often criticized or even rejected within the community. Some fluent speakers at Standing Rock have not accepted the new writing system. There are some who continue to work in language education and who use the LLC materials but do not write in the orthography. These are usually Elders who remain in the habit of writing the way they learned. A few people at Standing Rock, however, have been offended by the notion of a standard way of writing Lakota/Dakota, especially one that seems unlike any of the systems used by Elders. Community members have been particularly wary of the SLO ['Standard Lakota Orthography'], which appears to be developed by outsiders who are not fluent speakers and would require considerable study for a fluent speaker to use."

In 2013 Lakota teachers at Red Cloud Indian School on Pine Ridge Indian Reservation discussed their use of orthography for their K-12 students as well as adult learners. The orthography used at Red Cloud "is meant to be more phonetic than other orthographies... That means there are usually more 'H's than other versions. While many orthographies use tipi... Red Cloud spells it thípi." He continues, "the orthography also makes heavy use of diacritical marks... that is not popular among some educators and academics". Delphine Red Shirt, an Oglala Lakota tribal member and a lecturer on languages at Stanford University, disagrees and prefers a Lakota orthography without diacritical marks. "I'm very against any orthography that requires a special keyboard to communicate," she said. First language speaker and veteran language teacher at Red Cloud, the late Philomine Lakota, had similar concerns with the orthography, and argues against changing the spelling forms she learned from her father. However, she did consider that, a shared curriculum could "create consistency across the region and encourage the long-term viability of the language. However, Philomine is also cognizant that it will take more than a school curriculum to preserve the language." She added, "In order for a language to survive, it can't simply be taught from the top. A language is a living thing and students need to breathe life into it daily; talking with friends, family and elders in Lakota".

In 2018, at the Cheyenne River Indian Reservation, Lakota speaker Manny Iron Hawk and his wife Renee Iron Hawk discussed opening an immersion school and the difficulties around choosing an orthography to write Lakota; Mr. Iron Hawk voiced support for the LLC (SLO) Orthography, saying it was accessible to second language learners, but know not all agreed with him. Others in the community voiced a preference for the tribe creating their own orthography. While Mr. Iron Hawk supports this approach, Renee Iron Hawk also expressed a sense of urgency, saying "We should just use what we have, and then fix and replace it, but we need to start speaking it now". The Iron Hawks both agreed that too much time has been spent arguing over which orthography to use or not use, and not enough time is spent teaching and speaking the language.

On May 3, 2022, the Tribal Council of the Standing Rock Sioux, in a near-unanimous vote, banished the Lakota Language Consortium (and specifically, LLC linguist Jan Ullrich and co-founder Wilhelm Meya) from ever again setting foot on the reservation. The council's decision was based on the LLC's history with not only the Standing Rock community, but also with at least three other communities that also voiced concerns about Meya and the LLC, "saying he broke agreements over how to use recordings, language materials and historical records, or used them without permission."

LLC alphabet
The "Standard Lakota Orthography" as the LLC calls it, is in principle phonemic, which means that each character (grapheme) represents one distinctive sound (phoneme), except for the distinction between glottal and velar aspiration, which is treated phonetically.

Lakota vowels are $⟨aŋ⟩$ nasal vowels are aŋ, iŋ, uŋ. Pitch accent is marked with an acute accent: $\langlegl\rangle$ on stressed vowels (which receive a higher tone than non-stressed ones)

The following consonants approximate their IPA values: $\langlebl\rangle$. $\langlegm\rangle$ has its English value of. An apostrophe, $\langleOglala\rangle$, is used for the glottal stop.

A caron is used for sounds, other than, which are not written with Latin letters in the IPA: $⟨m⟩$ , $⟨n⟩$ , $⟨ň⟩$ , $⟨p⟩$ , $⟨t⟩$. Aspirates are written with $⟨č⟩$: $⟨k⟩$ and velar frication with $⟨ʼ⟩$: $⟨b⟩$ Ejectives are written with an apostrophe: $⟨g⟩$.

The spelling used in modern popular texts is often written without diacritics. Besides failing to mark stress, this also results in the confusion of numerous consonants: and  are both written $⟨ph⟩$,  and  are both written $⟨pȟ⟩$, and the aspirate stops are written like the unaspirates, as $⟨th⟩$.

All digraphs (i.e. characters created by two letters, such as kh, kȟ, k') are treated as groups of individual letters in alphabetization. Thus for example the word čhíŋ precedes čónala in a dictionary.

Curley alphabet
In 1982, Lakota educator Leroy Curley (1935-2012) devised a 41-letter circular alphabet.

Word order
The basic word order of Lakota is subject–object–verb, although the order can be changed for expressive purposes (placing the object before the subject to bring the object into focus or placing the subject after the verb to emphasize its status as established information). It is postpositional, with adpositions occurring after the head nouns: mas'óphiye él, "at the store" (literally 'store at');, "around the house" (literally 'house=the around') (Rood and Taylor 1996).

Rood and Taylor (1996) suggest the following template for basic word order. Items in parentheses are optional; only the verb is required. It is therefore possible to produce a grammatical sentence that contains only a verb. "(interjection) (conjunction) (adverb(s)) (nominal) (nominal) (nominal) (adverb(s)) verb (enclitic(s)) (conjunction)"

Interjections
When interjections are used, they begin the sentence or end it. A small number of interjections are used only by one gender, for instance the interjection expressing disbelief is ečéš for women but hóȟ for men; for calling attention women say máŋ while men use wáŋ. Most interjections, however, are used by both genders.

Conjunctions
It is common for a sentence to begin with a conjunction. Both čhaŋké and yuŋkȟáŋ can be translated as and; k’éyaš is similar to English but. Each of these conjunctions joins clauses. In addition, the conjunction na joins nouns or phrases.

Adverbs, postpositions and derived modifiers
Lakota uses postpositions, which are similar to English prepositions, but follow their noun complement. Adverbs or postpositional phrases can describe manner, location, or reason. There are also interrogative adverbs, which are used to form questions.

Synonymity in the postpositions él and ektá
To the non-Lakota speaker, the postpositions él and ektá sound like they can be interchangeable, but although they are full synonyms of each other, they are used in different occasions. Semantically (word meaning), they are used as locational and directional tools. In the English language they can be compared to prepositions like "at", "in", and "on" (when used as locatives) on the one hand, and "at", "in", and "on" (when used as directionals), "to", "into", and "onto", on the other. (Pustet 2013)

A pointer for when to use él and when to use ektá can be determined by the concepts of location (motionless) or motion; and space vs. time. These features can produce four different combinations, also called semantic domains, which can be arranged as follows (Pustet 2013):

 * 1) space / rest: "in the house" [thípi kiŋ él] (This sentence is only describing location of an object, no movement indicated)
 * 2) space / motion: "to the house [thípi kiŋ ektá] (This sentence is referring to movement of a subject, it is directional in nature)
 * 3) time / rest: "in the winter" [waníyetu kiŋ él] (This sentence refers to a static moment in time, which happens to be during winter)
 * 4) time / motion: "in/towards the winter" [waníyetu kiŋ ektá] (Pustet 2013) (This sentence is delegated to time, but time which is soon to change to another season)

Summed up, when a context describes no motion, él is the appropriate postposition; when in motion, ektá is more appropriate. They are both used in matters of time and space.

Nouns and pronouns
As mentioned above, nominals are optional in Lakota, but when nouns appear the basic word order is subject–object–verb. Pronouns are not common, but may be used contrastively or emphatically.

Lakota has four articles: waŋ is indefinite, similar to English a or an, and kiŋ is definite, similar to English the. In addition, waŋží is an indefinite article used with hypothetical or irrealis objects, and k’uŋ is a definite article used with nouns that have been mentioned previously.

Demonstratives
There are also nine demonstratives, which can function either as pronouns or as determiners.

Verbs
Verbs are the only word class that are obligatory in a Lakota sentence. Verbs can be active, naming an action, or stative, describing a property. (In English, such descriptions are usually made with adjectives.)

Verbs are inflected for first-, second- or third person, and for singular, dual or plural grammatical number.

Verb inflection
There are two paradigms for verb inflection. One set of morphemes indicates the person and number of the subject of active verbs. The other set of morphemes agrees with the object of transitive action verbs or the subject of stative verbs.

Most of the morphemes in each paradigm are prefixes, but plural subjects are marked with a suffix and third-person plural objects with an infix.

First person arguments may be singular, dual, or plural; second or third person arguments may be singular or plural.

Examples: máni "He walks." mánipi "They walk."

Example: waŋwíčhayaŋke "He looked at them" from waŋyáŋkA "to look at something/somebody".

Subject and object pronouns in one verb If both the subject and object need to be marked, two affixes occur on the verb. Below is a table illustrating this. Subject affixes are marked in italics and object affixes are marked in underline. Some affixes encompass both subject and object (such as čhi- ...). The symbol ∅ indicates a lack of marking for a particular subject/object (as in the case of 3rd Person Singular forms). Cells with three forms indicate Class I, Class II, and Class III verb forms in this order.

Example: uŋkánipȟepi "We are waiting for you" from apȟé "to wait for somebody". Example: iwíčhauŋkičupi "We took them" from ičú "to take something/somebody".
 * 1 The affix čhi- covers cases where I-subject and you-object occurs in transitive verbs.
 * 2 Class II and Class III verbs have irregular yal- and yan- respectively.
 * 3 These prefixes are separated when uŋ(k)- must be prefixed while ni- et al. must be infixed.
 * 4 uŋ(k)- precedes all affixes except wičha-. In the last column, verbs which require uŋ(k)- to be prefixed are more complex because of competing rules: uŋ(k)- must be prefixed, but must also follow wičha-. Most speakers resolve this issue by infixing wičhauŋ(k) after the initial vowel, then repeating the initial vowel again.
 * 5 Since the suffix -pi can appear only once in each verb, but may pluralize either subject or object (or both), some ambiguity exists in the forms: uŋ- ... -pi, uŋni- ... -pi, and uŋya-/uŋl-/uŋn- ... -pi.

Enclitics
Lakota has a number of enclitic particles which follow the verb, many of which differ depending on whether the speaker is male or female.

Some enclitics indicate the aspect, mood, or number of the verb they follow. There are also various interrogative enclitics, which in addition to marking an utterance as a question show finer distinctions of meaning. For example, while he is the usual question-marking enclitic, huŋwó is used for rhetorical questions or in formal oratory, and the dubitative wa functions somewhat like a tag question in English (Rood and Taylor 1996; Buchel 1983). (See also the section below on men and women's speech.)

Men's and women's speech
A small number of enclitics (approximately eight) differ in form based on the gender of the speaker. Yeló (men) ye (women) mark mild assertions. Kštó (women only according to most sources) marks strong assertion. Yo (men) and ye (women) mark neutral commands, yetȟó (men) and nitȟó (women) mark familiar, and ye (both men and women) and na mark requests. He is used by both genders to mark direct questions, but men also use hųwó in more formal situations. So (men) and se (women) mark dubitative questions (where the person being asked is not assumed to know the answer).

While many native speakers and linguists agree that certain enclitics are associated with particular genders, such usage may not be exclusive. That is, individual men sometimes use enclitics associated with women, and vice versa (Trechter 1999).

Ablaut

 * All examples are taken from the New Lakota Dictionary.

The term "ablaut" refers to the tendency of some words to change their final vowel in certain situations. Compare these sentences.

 * Šúŋka kiŋ sápa čha waŋbláke.
 * Šúŋka kiŋ sápe.
 * Šúŋka kiŋ sápiŋ na tȟáŋka.

The last vowel in the word "SápA" changed each time. This vowel change is called "ablaut". Words which undergo this change are referred to as A-words, since, in dictionary citations, they are written ending in either -A or -Aŋ. These words are never written with a final capital letter in actual texts. Derivatives of these words generally take the ablaut as well, however there are exceptions.

There are three forms for ablauted words: -a/-aŋ, -e, -iŋ. These are referred to as a/aŋ-ablaut, e-ablaut, and iŋ-ablaut respectively. Some words are ablauted by some and not others, like "gray" hóta or hótA. Ablaut always depends on what word follows the ablauted word.

A/aŋ-ablaut
This is the basic form of the word, and is used everywhere in which the other forms are not utilized.

E-ablaut
There are two cases in which e-ablaut is used.
 * 1) Last word in the sentence
 * 2) Followed by a word which triggers e-ablaut

1. Last word in sentence

 * Examples
 * Héčhiya yé He went there. (e-ablaut of the verb yÁ)
 * Yúte She ate it. (e-ablaut of the verb yútA)
 * Thípi kiŋ pahá akáŋl hé. The house stands on a cliff. (e-ablaut of the verb hÁŋ)

2. Followed by a word which triggers e-ablaut
There are three classes of words which trigger e-ablaut

 * 1) various enclitics, such as ȟča, ȟčiŋ, iŋčhéye, kačháš, kiló, kštó, któk, lakȟa, -la, láȟ, láȟčaka, ló, séčA, sékse, s’eléčheča, so, s’a, s’e, šaŋ, šni, uŋštó
 * 2) some conjunctions and articles, such as kiŋ, kiŋháŋ, k’éaš, k’uŋ, eháŋtaŋš
 * 3) some auxiliary verbs, such as kapíŋ, kiníča (kiníl), lakA (la), kúŋzA, phiča, ši, wačhíŋ, -yA, -khiyA

 * Examples

 * Škáte šni. He did not play. (enclitic)
 * Škáte s’a. He plays often. (enclitic)
 * Škáte ló. He plays. (enclitic (marking assertion))
 * Okȟáte háŋtaŋ... If it is hot... (conjunctive)
 * Sápe kiŋ The black one (definite article)
 * Glé kúŋze. He pretended to go home. (auxiliary verb)
 * Yatké-phiča. It is drinkable. (auxiliary verb)

Iŋ-ablaut
The iŋ-ablaut (pronounced i by some) occurs only before the following words:

 * ktA (irrealis enclitic)
 * yetȟó (familiar command enclitic)
 * na, naháŋ (and)
 * naíŋš (or, and or)
 * yé (polite request or entreaty enclitic)

 * Examples

 * Waŋyáŋkiŋ yetȟó. Take a look at this, real quick.
 * Yíŋ kte. She will go.
 * Skúyiŋ na wašté. It was sweet and good.
 * Waŋyáŋkiŋ yé. Please, look at it.

Phrases
"Háu kȟolá", literally "Hello, friend", is the most common greeting, and was transformed into the generic motion picture American Indian "How!", just as the traditional feathered headdress of the Teton was "given" to all movie Indians. As háu is the only word in Lakota which contains a diphthong,, it may be a loanword from a non-Siouan language.

Language revitalization efforts
Assimilating Indigenous peoples into the expanding American society of the late 19th and early 20th centuries depended on suppression or full eradication of each tribe's unique language as the central aspect of its culture. Indian residential schools in the US and Canada that separated Indigenous children from their parents and relatives enforced this assimilation process with beatings and other forms of violence for speaking tribal languages(Powers). The Lakota language survived this suppression. "Lakota persisted through the recognized natural immersion afforded by daily conversation in the home, the community at reservation-wide events, even in texts written in the form of letters to family and friends. people demonstrated their cultural resilience through the positive application of spoken and written Lakota." (Powers)

Even so, employment opportunities were based on speaking English; a Lakota who was bilingual or spoke only English was more likely to be hired.

In 1967, the Red Cloud Indian School at Pine Ridge began offering Lakota language classes. This was over two decades before the Native American Languages Act of 1990.

In the mid-1970s the Rosebud Reservation established their Lakota Language and Culture department at the Sinte Gleska University under the chairmanship of Ben Black Bear, Jr., who employed textbooks and orthography developed by the Colorado University Lakota Project (CULP). A few years later Black Bear was replaced as a chair of the department by Albert White Hat, who discontinued the use of the Colorado University textbooks. In 1992 White Hat published a textbook with his own orthography, for use at all levels of language learning on Rosebud. Sinte Gleska University now uses the orthography developed by Albert White Hat.

In 2002 Sinte Gleska University rejected the Lakota Language Consortium invitation to support their organization. Rosebud Cultural Studies teacher Randy Emery spoke to the Lakota Journal, stating, "The Lakota Language Consortium has created the misleading impression that Sinte Gleska University is one of the schools that supports their organization," and that the LLC had circulated a document to this effect with other misleading information about the state of the language, "The (LLC) documentation strongly implies that there are no fluent speakers younger than the elder age group and the presentation implies that the Lakota cannot deal with the problem themselves; therefore outside help must be brought in to lead the program. This appears to us as a sugar coated attack on sovereignty".

In 2008, the Red Cloud School at Pine Ridge launched their Lakota language curriculum for K-12 students. In November 2012, the incoming president of the Oglala Sioux Tribe, Bryan Brewer, announced that he intended "to lead a Lakota Language Revitalization Initiative that will focus on the creation and operation of Lakota language immersion schools and identifying all fluent Lakota speakers." A Lakota language immersion daycare center is scheduled to open at Pine Ridge. Also in 2012, Lakota immersion classes were provided for children in an experimental program at Sitting Bull College on the Standing Rock Reservation, where children speak only Lakota for their first year. Tom Red Bird is a Lakota teacher at the program who grew up on the Cheyenne River Reservation. He believes in the importance of teaching the language to younger generations as this would close the gap in the ages of speakers. In 2014, it is estimated that about five percent of children age four to six on Pine Ridge Indian Reservation speak Lakota. Language Revitalization efforts continued to be strengthened by the establishment of several independent, grassroots Lakota language immersion schools and camps, such as those at the Dakota Access Pipeline protests camps at Standing Rock in 2016.

On May 3, 2022, the Standing Rock Sioux Tribal Council passed Resolution Number 150-22, which, along with banishing the LLC, contains provisions to protect the Nation's intellectual property rights and data sovereignty. "It reclaimed copyrights over all language materials created by the consortium and called for their immediate return, to be placed in the care of “the first-language speakers and knowledge-keepers in our communities.'"

Lakota Language Education Program (LLEAP)
In 2011, Sitting Bull College (Fort Yates, North Dakota, Standing Rock) and the University of South Dakota began degree programs to create effective Lakota language teachers. By earning a Bachelor of Arts in education at the University of South Dakota or a Bachelor of Science in education at Sitting Bull College, students can major in "Lakota Language Teaching and Learning" as part of the Lakota Language Education Action Program, or LLEAP.

LLEAP is a four-year program designed to create at least 30 new Lakota language teachers by 2014, and was funded by $2.4 million in grants from the U.S. Department of Education. At the end of the initial phase, SBC and USD will permanently offer the Lakota Language Teaching and Learning degree as part of their regular undergraduate Education curriculum. The current LLEAP students' tuition and expenses are covered by the grant from the U.S. Department of Education. LLEAP is the first program of its kind, offering courses to create effective teachers in order to save a Native American language from going extinct, and potentially educate the 120,000 prospective Lakota speakers in the 21st century.

Government support
In 1990, Senator Daniel Inouye (D-HI) sponsored the Native American Languages Act in order to preserve, protect, and promote the rights and freedoms of Native people in America to practice, develop and conduct business in their native language. This law, which took effect on October 30, 1990, reversed over 200 years of American policy that would have otherwise eliminated the indigenous languages of the United States. This legislation gave support to tribal efforts to fund language education programs.

Self-study external links
Some resources exist for self-study of Lakota by a person with no or limited access to native speakers. Here is a collection of selected resources currently available:

Additional print and electronic materials have been created by the immersion program on Pine Ridge.

 * Lakota: A Language Course for Beginners by Oglala Lakota College (ISBN 0-88432-609-8) (with companion 15 CDs/Tapes) (high school/college level)
 * Reading and Writing the Lakota Language by Albert White Hat Sr. (ISBN 0-87480-572-4) (with companion 2 tapes) (high school/college level)
 * University of Colorado Lakhota Project: Beginning Lakhota, vol. 1 & 2 (with companion tapes), Elementary Bilingual Dictionary and Graded Readings, (high school/college level)
 * Lakota Dictionary: Lakota-English/English-Lakota, New Comprehensive Edition by Eugene Buechel, S.J. & Paul Manhart (ISBN 0-8032-6199-3)
 * English-Lakota Dictionary by Bruce Ingham, RoutledgeCurzon, ISBN 0-7007-1378-6
 * A Grammar of Lakota by Eugene Buechel, S.J. (professional level)
 * The article by Rood & Taylor, in (professional level)
 * Dakota Texts by Ella Deloria (a bilingual, interlinear collection of folktales and folk narratives, plus commentaries). (University of Nebraska Press, ISBN 0-8032-6660-X; professional level) (Note: the University of South Dakota edition is monolingual, with only the English renditions.)
 * A "Lakota Toddler" app designed for children ages 2–9 is available for the iPhone.
 * Matho Waunsila Tiwahe: The Lakota Berenstain Bears. DVD of 20 episodes of The Berenstain Bears, dubbed in Lakota with fluent Native speakers.

Lakota influences in English
Just as people from different regions of countries have accents, Lakota who speak English have some distinct speech patterns. These patterns are displayed in their grammatical sequences and can be heard through some phonological differences. These unique characteristics are also observed in Lakota youth, even those who only learned English.

title: Lakota language


text:
Kasai River

The Kasai River (Mto Kasai, Kasaï ; called   in Angola) is a left bank tributary of the Congo River, located in Central Africa. The river begins in central Angola and flows to the east until it reaches the border between Angola and the Democratic Republic of the Congo, where it turns north and serves as the border until it flows into the DRC. From Ilebo, between the confluences with Lulua river and Sankuru river, the Kasai river turns to a westerly direction. The lower stretch of the river, from the confluence with Fimi river until it joins the Congo at Kwamouth northeast of Kinshasa, is also known as the Kwa(h) River.

The Kasai basin consists mainly of equatorial rainforest areas, which provide an agricultural land in a region noted for its infertile, sandy soil. It is a tributary of Congo river and diamonds are found in it. Around 60% of diamonds in Belgium go from Kasai river for cutting and shaping.

Exploration
Henry Morton Stanley reached the confluence on 9 March 1877, calling the river Nkutu, a "powerful and deep river", but recognizing it as originating from David Livingstone's Kwango.

Tributaries
The Kasai's main tributaries upstream from the confluence with the Congo:
 * Fimi (Fimi-Lukenie length 1100 km, basin size 132 000 km2, mean annual discharge ~ 2000 m3/s)
 * Kwilu/Kwango (1800 km, 263 500 km2, 3299 m3/s)
 * Loange
 * Sankuru (1200 km, 156 000 km2, 2500 m3/s)
 * Lulua

Economic importance
The tributaries of River Kasai are clear of obstacles like cataracts and river weed, making them very navigable. They facilitate the transport sector and form an important trade artery. The river's role in transport and trade was more prominent during the pre-colonial period when the slave trade was legal. Slave traders used one of its major tributaries, the Kwango River, to navigate the equatorial rain forest, capture slaves and find their way back to the Atlantic Ocean where they had docked their ships. It is greatly controversial that some of the local kingdoms that were along the Kasai River supported the slave trade. The Rund kingdom for instance, readily provided slaves for the most notorious slave traders like John Matthews, a renowned British slave vendor. These activities, though they occurred between the 18th and 19th centuries, left a lasting impact in the regions where they were most prominent, such as between the Kwango and the Kwilu rivers. The population has never recovered fully, with the population density lower than that of areas that did not experience the slave trade. The most probable trigger to British and Portuguese great interests in the Kasai River was the presence of alluvial diamonds lying in rich deposit beds, especially at the river's mouth. More deposits lie along the beds of a major tributary, the Kwango River. In fact, it is common to hear the phrase “the diamond heartland of North Eastern Angola” used in reference to the Kwango River valley. This is because the diamond alluvial beds found in this region are the richest in Angola.

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

title: Kasai River


text:
Talk:Epidemic

Bill Gates is not a primary source
Suggesting that Bill Gates is making these statements and not just repeating the primary source that should be cited is ludicrous. Bill Gates is a billionaire best known for his for being for taking intellectual property from Xerox and re-marketing it as his own product (the irony of then later taking the credit for other scientists and re marketing it as his own to improve his public image as a pirate and a thief is really mind-bending), then taking the profit from that to hire engineers to build new other products.

Bill Gates is not and has never been a scientist, he is certainly not an epidemiologist, and perhaps most importantly has no formal training or education on any biological sciences. His name being on a charity does not provide him with super powers, or special knowledge. If anything, it is widely understood by historians that when billionaires (or the equivalent throughout history) open up charities later in their careers are primary used to avoid taxes, grant them the ability to wield some political power, and most importantly: white-wash their public image.

Crediting him for statements he said on NPR, that were clearly made by actual epidemiologist (in fact, as a Biologist I absolutely have heard these statements made many times, also citing epidemiologists is to willfully pretend that he was involved in epidemiological research in any way.

To pretend that he is an somehow an expert in epidemiology, or that these statements are his when he is clearly repeating lines he was told or he read in an abstract of an actual peer-reviewed paper on epidemiology is not just so absurd that it reeks of a PR consultant using this article and articles like it to enhance his public image, but **most importantly it violates Wikipedia's guideline**. The fact that I have to even say this is really suspect. This is obvious to anyone has is even somewhat familiar with Wikipedia.

There are rules about using primary sources, and I have a hard time believing anyone in good faith honestly thought that national public radio, is a primary source for epidemiological facts instead one of the many epidemiological peer-reviewed journals.

The problem in this article is so bad that there is more direct quotes from Bill Gates as previously stated "he is clearly repeating lines he was told by an epidemiologist or he read in an abstract of an actual peer-reviewed paper on epidemiology" than actual quotes from epidemiologists or even quotes from sources that are from peer-reviewed epidemiological journals.**

Citing his statements in an interview on NPR, when we all know hes not an epidemiologist, and has never written a peer reviewed scientific article means he is second hand source, and that using this source violating Wikipedia's guidelines and requirements. And I have a really hard time believe anyone in good faith honestly thought otherwise.

This article should have been quoting and citing scientific articles, and why do I even need to says this? An article on a scientific topic where "npr.org" used many times? This should have been a red flag for every editor who has read this. When everyone knows NPR is not even science focused, and it is certainly NOT a primary source for anything science related, and not epidemiology.

In fact, if anything, scientists I talk to know NPR regularly fails to properly report things on the topic of science. They are a very poor resource even simple science related coverage. They regularly misreport the rise in Heroine deaths in the United States as a "Heroine Epidemic", which is not just in accurate in the scientific sense, its inaccurate in every sense from definition to the fact that is the numbers being reported for Heroine overdose would have qualified car deaths as an epidemic for the last 50 years running, but you will absolutely never find any reference to car deaths being an epidemic. Whoever authored that section appear to be involved in public relations, obviously there is no real way to prove it but the blatant violation of Wikipedia Guidelines make it appear at least surface to be a public relations related. — Preceding unsigned comment added by Faraday-mage (talk • contribs) 00:21, 8 March 2019 (UTC)

Definition
Epidemic is used, generally, to refer to the spread of pathogens in a population. Demos is greek for 'upon the population' and as such is technically able to be (and is in scientific literature) used instead of the needlessly more complicated epizootic or epiphytotic. Epidemiologists can refer to those who study epidemics in humans, plants and animals. I'm forwarding the idea that this whole page needs a re-write in terms of epidemics as it is generally used with sections for humans, animals and plants. —Preceding unsigned comment added by 149.155.96.6 (talk) 10:51, 30 July 2010 (UTC)

Definition
I do not know what epidemic

Please somebody add what causes epidemics to spread. -Thanks

non-biological is not accurate - should be "other" biological uses.
When you mention "non-biological" uses, I think you mean "non-infectious-disease". Surely everyone agrees that obesity, drug addiction, and mental illness are biological! I would suggest changing this to read "other" uses.

Perhaps a true non-biological "epidemic" would be something like a video game or clothing fashion? —Preceding unsigned comment added by 78.86.8.103 (talk) 12:46, 12 October 2007 (UTC)

Death of people?!?
What does the line "Epidemics lead to death of people" in the non-biological section mean? It's completely inappropriate and out of the blue! Well, that's my opinion anyway. --24.46.164.83 05:25, 14 November 2007 (UTC)

Add some more links
I introduced more text. Please make internal links at important words on the text. KVDP (talk) 18:45, 7 February 2008 (UTC)

Merge?
There is a call to merge Pandemic (which is a full description) into Epidemic (which is a stub-and-pointer). I disagree, don't merge, even at the price of duplication. This section contributes valuable information to anyone looking up Pandemics, which is probably millions of people about now. Jdonovan43 (talk) 23:45, 29 April 2009 (UTC)
 * Reject. The text in Pandemic is quite OK where it is.Anthony Appleyard (talk) 15:56, 11 April 2008 (UTC)
 * Comment. Perhaps an entirely new page List of notable epidemics (history would be assumed) is called for?--ZayZayEM (talk) 01:52, 23 October 2008 (UTC)

Healthmap
Perhaps healthmap (http://www.healthmap.org/en/ ) should be mentioned as a pre-emptive measure ? —Preceding unsigned comment added by 91.182.223.239 (talk) 09:32, 4 October 2010 (UTC)

“Pre-emptive measures” ¿Such As?
The link included only references a PDF entitled “Report of the WHO/FAO/OIE joint consultation on emerging zoonotic diseases.” It doesn’t tell us anything about what WHO nor anyone else is doing to pre-empt new epidemics. (It’s not that I doubt they are doing something, but some clue as to what would help.)174.25.121.131 (talk) 16:29, 7 October 2010 (UTC)A REDDSON

Health crisis
Las crisis sanitarias no tienen porque ser necesariamente una epidemia o una pandemia, pueden originarlas también desastres de origen humano o natural. Las crisis sanitarias pueden proceder de alimentos, de infecciones, o problemas medioambientales; siempre suponiendo que estemos en tiempos de paz. Las actuaciones para resolverlas son múltiples: médicas, económicas, políticas, etc. Pueden afectar a una localidad concreta, a una región, a un país, a un continente o a todo el planeta. Por todo ello, crisis sanitaria (Health crisis) no corresponde con epidemia (epidemic) y debe ser un artículo independiente. Un cordial saludo:Raimundo Pastor (talk) 15:18, 28 August 2011 (UTC)

 * Well, I'm not sure that's what the sources you're using say... and epidemic need not be just a disease. They are functionally the same... and if "health crisis" is anything that endangers human life or well being, as you say, then that's just a crisis or disaster. While you may find sources that use any number of different terms, if they all address the same concept they should be in a single article. Both the new health crisis article and the epidemic article are small underdeveloped articles. Both could be merged into a much more useful, elaborate article. There are lots of catchphrase concepts that get thrown around by various fields... business students are notorious for this kind of terminology swamp. When, however, they address the same functional concept they should be merged.

 * This would all be much easier too if the health crisis definition was defined outright. From my estimation the sources merely use the term and concept. They aren't about the term or concept. That makes it difficult to really see the difference, if there is any, between the two. But perhaps I missed something. If so, please point that out. Shadowjams (talk) 21:13, 28 August 2011 (UTC)

Friendly:Raimundo Pastor (talk) 22:31, 28 August 2011 (UTC)

Random all-caps words?
The main paragraph in the Causes section has the names of certain diseases in capital letters, for no apparent reason. Unless this is usually for disease names (which I'm fairly sure it isn't), then my only guess is that it's vandalism or was an inexperienced editor's attempt to create links. Does anyone object to me replacing them with non-caps words and making some of them into links? 150.203.192.134 (talk) 06:19, 3 October 2012 (UTC)
 * West Nile is capitalized because it's the name of a river. Disease names with proper nouns are capitalized (St. Louis encephalitis, Weil disease) but the eponymic form is discouraged now (Weil's disease). JuanTamad (talk) 00:01, 11 September 2016 (UTC)

Lede sentence (and much of the article) over-emphasizes rapidity, scope, and infectious disease
As ref #1 (the CDC text on Fundamentals of Epidemiology) and other sources note, epidemics need neither involve large numbers of people, be rapid, nor even be transmissible - yet those are the clear messages in the lead. Any increase (sudden or not) of any disease (communicable or not) above its baseline incidence (high or low) in a population is considered an epidemic. A subsequent section does note that the epidemic might be something non-transmissible like obesity, and the last sentence of the lead does acknowledge that high rates are not a requirement for "epidemic" status, but the lead sentence should not be so restrictive - it's all many readers will see. I am reluctant to boldly change that lead sentence without discussion, because (i) it might not be understood by active editors here, and (ii) a major change in the focus of the article is the subtext - the second paragraph, for example, might be out of place if the focus weren't so squarely on communicable disease. — soupvector (talk) 23:54, 10 September 2016 (UTC)
 * Agree that the first sentence could be better written, but the use of the term in infectious disease is original and well defined, with specific definitions. There should be brief mention of use of the term in non-infectious diseases  like obesity but note that it's use in that sense is less formal. I think, sort of borrowed from infectious disease. JuanTamad (talk) 00:11, 11 September 2016 (UTC)
 * If one refers to the glossary of (freely-available) ref #1 (as cited currently, it's the CDC's Fundamentals of Epidemiology text), it defines: "epidemic the occurrence of more cases of disease, injury, or other health condition than expected in a given area or among a specific group of persons during a particular period. Usually, the cases are presumed to have a common cause or to be related to one another in some way (see also outbreak)." The Introduction of that text, on page 1-73, uses language we could consider: "The previous description of epidemics presumes only infectious agents, but non-infectious diseases such as diabetes and obesity exist in epidemic proportion in the U.S." — soupvector (talk) 02:02, 11 September 2016 (UTC)
 * I have added the quoted CDC definition to the article section Definition; it should help to clarify some of the points raised here, supports the lede, and it leads nicely into the note on 'epidemic' vs 'outbreak'. --D Anthony Patriarche (talk) 09:02, 22 March 2020 (UTC)

definition too specific? not all epidemics involve infectious disease, such as the obesity epidemic
I was searching for a information about what defines an obesity epidemic and ended up here. The definition here seems to imply an epidemic must be the rapid spread of an infectious disease. But since obesity is not infectious, perhaps a broader definition would be more appropriate. How about making the definition closer to the Merriam-Webster definition; something like: "An epidemic is a disease or medical disorder that affects a large proportion of a population at a particular time." Following that, it could be mentioned that epidemics typically involve the rapid spread of an infectious disease, etc. — Preceding unsigned comment added by 1.165.233.4 (talk) 01:35, 9 May 2017 (UTC)
 * See my comments in previous section (immediately above). Agree this should be addressed. — soupvector (talk) 18:54, 9 May 2017 (UTC)

External links modified (January 2018)
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Epidemic restricted to "infectious disease"?
In the "Causes" section, it's stated that an epidemic is not required to be contagious, and it's pointed out that the term is applied by the WHO to the "obesity epidemic." Given that obesity is not an infectious disease, it seems this contradiction should be resolved by deleting the word "infectious" in the first sentence in the lead. I'll be doing this if nobody has any objections. Global Cerebral Ischemia (talk) 12:53, 12 March 2020 (UTC)
 * Wow, just noticed this was already brought up two years ago! The WHO's use of the term is clear. I'll be deleting "infectious." Global Cerebral Ischemia (talk) 12:55, 12 March 2020 (UTC)
 * Good catch. I've also added the CDC's very broad definition to the Definition section, which supports this. Please be careful, though, of the word contagious; it's not an exact synonym for infectious, it's more restrictive, but the definition is somewhat fuzzy and has changed with time. It literally means 'spread by touch', i.e. direct contact, but it has been broadened to include contact with infected fluids. One used to be able to say, 'crabs is contagious, but influenza is infectious'; but even that distinction has now become blurred. 'Contagious' used to include the STDs which are spread by direct contact, but STDs have now been given their own class. I would avoid using the word altogether unless the context absolutely requires the distinction. I did start to change the word 'contagious' in the article to 'infectious', or 'contagious or infectious', but realized I was opening a can of worms (e.g. is Nile Fever contagious or infectious?) and would have to recast the whole sentence. I think the average reader will understand it in context, so I let it be. --D Anthony Patriarche (talk) 10:22, 22 March 2020 (UTC)

Epidemic
Vulnerability of the topic 103.171.194.54 (talk) 04:09, 12 December 2021 (UTC)

The locations or areas
A few comments:
 * 1) I add the note that epidemics has specific area, or initial area. To this initial area can be added also other areas within a country bouderies or sometimes to cross these borders and for example spread to boundering country, and if the epidemic continues to spread with months or years it may go on some countries in a given region, or even in pandemic cross continents. \this note explains article eddits done by me\
 * 2) Changes in ecology has to be significant compared to usual to cause epidemic, or in other way conditions to worsen that to be noticed in nature ecology.
 * 3) Added internal link for vector species for anyone who wants to quickly check the meaning of it.
 * 4) Added "unexpected" to genetic change because most genetic changes are due to adapting not causing diseases.
 * 5) Which is first, the introduction to patogen, later may some unexpected change to appear. I made it clear because it is possible that different people added this information at different time and couldn't make it to arrange it well in a logical sentence.
 * 6) Using words like generally does not comply with one source only for the worldwide read Engish Wikipedia, I think you need to have 2 or 3 sources to make logical that something "generally" occurs. Especially you cannot use single dictionary or dictionary pages to make conclusions on "genreally", you need serious medical and current sources for it. Not to mention I don't see literary no relation of the reference source to the stated sentence. In this page is not discussed "novel pathogens". So I added short description of what this dictionary page says about epidemiology and moved to reference to this explanation because the stated seems without real reference within this quoted literature on epidemiology. Maybe someone can find a real reference source on it but I don't see grounds for such claims.
 * 7) Announcing an epidemiological levels of disease is not the same as "declaration", that has some emotional connotations in law.
 * 8) Epidemics does not derive from Homer, I'm sorry, there is no Greek studies prove to show that Homer was a scientist in the epidemic medicine. Epi is not the same as epos. Epic epidemic sounds funny but I don't think it truth. Its just cool to joke like this but I will change the origins of the word explained.
 * 9) In fact, according to early sources, it was Hippocrates who first noticed that some diseases have epidemic type but called it differently. The term epidemic seems to be first noticed in Thucydides who wrote during the time of Hippocrates on Peloponnesian wars. --Medupdate3 (talk) 09:42, 9 June 2022 (UTC)

Reverting awful edits made by Medupdate3 (see section above)
So the editor above was blocked for being a sockpuppet, but his terrible edits are still here. I have no idea why he wasn't immediately reverted. The lead is now largely incomprehensible and even incompetent, and the body has suffered too. Reverting by hand would take a very long time so I'm reverting to the last state before he made those edits. Since then the only edits have been people fixing some of his many spelling mistakes and some other minor changes anyway. Prinsgezinde (talk) 21:53, 6 February 2023 (UTC)

"Ulytrafiolet".
Што мешает в кассовые аппараты встроить излучатели ультрафиолета ? Если даже полупроводниковые. Да ничего. 85.140.11.44 (talk) 03:23, 29 July 2023 (UTC)

Waves
I've just removed an IP-sourced para about waves. I haven't found a reliable secondary source to substantiate it. WP:NOR and WP:SECONDARY apply. Bob (talk) 20:56, 29 August 2023 (UTC)

title: Talk:Epidemic


text:
Talk:Neoprene

is it waterproof?
The article doesn't say —Preceding unsigned comment added by 88.108.87.11 (talk) 18:55, 27 February 2011 (UTC)

No. That's why they call a wetsuit a "wet"suit. Water leaks thru neoprene, at least the kind of neoprene they use to make my diving wetsuit. Divers who want to stay dry use a different kind of suit called a "drysuit" and it's made of different material.

joint braces?
neoprene is also used in the creation of braces for our joints.

Neoprene Dangers
In the article it mentions how lead and various other chemicals and or elements are used in production that can make neoprene harmful; I'd like to know how to minimize or eliminate the threat of these substances (specifically the lead). Is there a cleaning method or some other solution? —Preceding unsigned comment added by 76.175.11.251 (talk) 15:10, 2 March 2010 (UTC)

crushed neoprene?
I am very curious what CRUSHED NEOPRENE is all about? Could anyone add some info about that? Thanks.

latex?
I'm curious about the relationship of neoprene to latex? Could someone respond? Thanks.

 * I don't think there is one -- latex is a natural rubber, neoprene a man-made rubber. --ukexpat 00:55, 17 May 2007 (UTC)

wouldn't it make sense to make a redirect page Neoprene rubber directing here?80.235.71.49 11:50, 5 September 2007 (UTC)

Referencing an external link
The fact tag in this article could be referenced from the external link but I don't know how to do that or if it is even appropriate since that external link may qualify to be listed under References. Could someone comment on this.--Papajohnin (talk) 05:54, 21 February 2008 (UTC)

 * Which of the fact tags are you talking about? The external link can be converted into a reference. It may be appropriate to do that. If you edit the first paragraph, you will see an example of how to cite a reference: "" - Neparis (talk) 16:42, 22 February 2008 (UTC)

Under Applications. The statement about Neoprene having more fire resistance than exclusively hydrocarbon based rubbers can be referenced by the external link here not the .pdf. The article on fire doors list neoprene weatherstripping as a component. Neoprene face mask and gloves can be verified by just typing it in Google - many companies make those items. So basically I tried to move the link to the DuPont website in "External Links" to "References" (right below the .pdf that is currently there) but when I edit References all I see is  .

When I try to add a reference in the format like yours it just says [1] and links to the .pdf instead of the DuPont website like I want it to. If you agree it should be done could you do it and show me what you did for future reference.--Papajohnin (talk) 05:55, 25 February 2008 (UTC)
 * Done. See this diff. - Neparis (talk) 01:07, 11 April 2008 (UTC)

No legitimate reference for open cell neoprene
I can not find any legitimate reference to open cell neoprene. In diving suits, it seems open cell means nylon lined. Many will sell you "open cell neoprene" but none are reliable sources of information, and the manufacturers and suppliers to industry don't sell it. The source referenced "open cell vs closed cell" notes that open cell foams are available in polyurethane or melamine foams, but mentions neoprene only under closed cell foams. I believe this reference should be removed unless a legitimate reference can be found. JohnLeroy (talk) 18:02, 2 April 2014 (UTC)

Alfonso Martorell Neoprene foam ¿is posible to recycle neoprene foam? ¿is posiible to recylce neoprene from diving suits? if I triturate neoprene foam in pieces, and then pulverice, what use can we do from this? Thanks AM — Preceding unsigned comment added by Alfonso martorell (talk • contribs) 21:13, 22 September 2018 (UTC)

Neoprene Density.
This page states that the density 'Can be compounded to 1.23g/cm3.'

Although this may be explicitly correct it can be misleading as Neoprene is generally not that densein bulk form. This is contradicted in subsequent paragraphs that say the foam is quite bouyant. Neoprene is commonly observed to float in water, implying therefore that its density is lower than water (1g/cm3).

I think it would be reasonable to have a density for solid neoprene, 1.23g/cm3 (Wood, L.A., Bekkedahl, N., Roth, F.L., 1942. Density Measurements on Synthetic Rubbers. Industrial & Engineering Chemistry 34, 1291–1293.. doi:10.1021/ie50395a008) and a measurement for foam neoprene of 0.100-0.300 g/cm3 (Naebe, M., Robins, N., Wang, X. and Collins, P., 2013. Assessment of performance properties of wetsuits. Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology, 227(4), pp.255-264.) & https://www.alanto.co.uk/information/glossary/what-is-neoprene#:~:text=Ref%20DK1410%20Density%20115%2D155,m3%2C%2040%2D45%20Shore%20Hardness — Preceding unsigned comment added by Oddroj (talk • contribs) 05:26, 8 February 2022 (UTC)

title: Talk:Neoprene


text:
Fimi River

The Fimi River (French: Rivière Fimi) is a river in the Democratic Republic of the Congo. It flows from Lake Mai-Ndombe to the Kasai River, which in turn empties into the Congo. One of the Fimi's tributaries is the Lukenie River, which is navigable by barges as far as Kole.

title: Fimi River


text:
Tape measure

A tape measure or measuring tape is a flexible ruler used to measure length or distance.

It consists of a ribbon of cloth, plastic, fibre glass, or metal strip with linear measurement markings. It is a common measuring tool. Its design allows for a measure of great length to be easily carried in pocket or toolkit and permits one to measure around curves or corners. Today it is ubiquitous, even appearing in miniature form as a keychain fob, or novelty item. Surveyors use tape measures in lengths of over 100 m.

Types
Tape measures are often designed for specific uses or trades. Tapes may have different scales, be made of different materials, and be of different lengths depending on the intended use. Tape measures can wind into a relatively small containers.

Tape measures that were intended for use in tailoring or dressmaking are called "sewing tape". They were made from flexible cloth or plastic, and are now made of fiberglass, which does not tear or stretch as easily. These types of tape measures are mainly used for the measuring of the subject's waist line and are usually 150 cm in length.

Measuring tapes designed for carpentry or construction often use a stiff, curved metallic ribbon that can remain stiff and straight when extended, but retracts into a coil for convenient storage. This type of tape measure will have a floating tang or hook on the end to aid measuring. The tang is connected to the tape with loose rivets through oval holes, and can move a distance equal to its thickness, to provide both inside and outside measurements that are accurate.

Self-marking tape measures allows the user have a graphite tip, allowing for accurate markings.

Cased measuring tape
There are two basic types of tape measures with cases: spring return pocket tape measures and long tape measures. Spring return pocket tape measures will generally fit in a pocket. They are small; the case is about 5 to 10 cm across. The tape is returned to the case by a spring mechanism. Pocket tape measures have a tape 0.3 to 10 m in length and 6 to 25 mm across.

A second tape measure design is what is called the long tape. These are cased tape measures with tapes of up to 200 m in length. It is designed for engineers and builders. Long tapes, instead of being returned by a spring, are usually returned by hand crank. Because surveying was usually done in rods, surveyors used long tapes of 2 rods (10.1 m, 33 feet), and 4 rods (20.1 m, 66 feet). Surveyors also used $49 1/2$ feet of a 50-foot tape for 3 rods and 99 feet of a 100-foot tape measure for 6 rods.

History
On 6 December 1864 patent #45,372 was issued to William H. Bangs of West Meriden, Connecticut. Bang's rule was the first attempt in the United States to make a spring return pocket tape measure. The tape could be stopped at any point and held by the mechanism. The tape could be returned to the case by sliding a button on the side of the case which then allowed the spring to pull the tape back into the case.

The first patented long tape measure in the United States was granted U.S. patent #29,096 issued 10 July 1860 to William H. Paine of Sheboygan, Wisconsin, and produced by George M. Eddy and Company of Brooklyn, New York. This tape had no increments on it. It accurately measured only a distance equal to the total length of the tape from beginning to end marker, a brass piece attached to the tape at a measured distance. The measured length was marked on the case or crank.

Later, by the early 1870s, Justus Roe of Patchogue, New York added rivets attaching small brass washers to the tape to mark inches and feet. They were attached every inch in the first and last foot and every foot from one to the end of the last foot. A small brass tag, marked with a number indicating the number of feet to that point, was attached every five feet. This feature was never patented, but Justus Roe and Sons produced tape measures, "Roe Electric Reel Tape Measures", with this feature during the 1890s and early 1900s when they started etching or stamping increments and numbers on the tapes. (The "electric" part of the name was purely an affectation; there was nothing electrical about it.)

On 3 January 1922, Hiram A. Farrand received patent #1,402,589 for his concave-convex tape, a major improvement for spring pocket tape measures. Between 1922 and December 1926, Farrand experimented with the help of The Brown Company in Berlin, New Hampshire. It is there Farrand and William Wentworth Brown began mass-producing the tape measure. Their product was later sold to Stanley Works. It was Farrand's concave-convex tape that went on to become the standard for the majority of pocket tape measure tapes today.

In the 1900's certain manufacturers started selling novelty tape measurers with prophecies and fortunes instead of numbers: users could check friends' heights and receive a fortune instead of their number.

In 1947, the Swedish engineer Ture Anders Ljungberg began developing an improved version and in 1954 the TALmeter was introduced. It features edges at both the end of the tape and the mouth to cut marks so measures (including arcs) can be transferred without reading the scale, as well as a fold-out metal tongue at the rear, also with an edge, to be used when taking internal measures. The tape has three scales: the normal metric, the internal scale and a diameter scale used for instance to measure sheet metal to be rolled into a cylinder of a certain diameter. It was produced by his own company T A Ljungberg AB until 2005, when it was bought by Hultafors in 2005, who retained the name "Talmeter" for the product they now refer to as a märkmeter (marker-meter).

In March 1963, Stanley Tools introduced the PowerLock tape measure series which defined the standard for tape measure form factors thats still persists today. It was novel in its use of a molded ABS case, thumb actuated tape lock, and riveted end hook. By 1989, Stanley was producing more than 200,000 tape measures every day.

The first commercialized Digital Tape Measure was released by Starrett in 1995 under the DigiTape brand. In March 2022, REEKON Tools announced the T1 Tomahawk Digital Tape Measure which featured significant accuracy improvements over previous attempts.

Design
The basic design on which all modern spring tape measures are built can trace its origins back to an 1864 patent by a Meriden, Connecticut resident named William H. Bangs Jr. According to the text of his patent, Bang's tape measure was an improvement on other versions previously designed.

The spring tape measure has existed in the U.S. since Bang's patent in 1864, but its usage did not become very popular due to the difficulty in communication from one town to another and the expense of the tape measure. In the late 1920s, carpenters began slowly adopting H. A. Farrand's design as the one more commonly used. Farrand's new design was a concave/convex tape made of metal which would stand straight out a distance of four to six feet. This design is the basis for most modern pocket tape measures used today.

With the mass production of the integrated circuit (IC) the tape measure has also entered into the digital age with the digital tape measure. Some incorporate a digital screen to give measurement readouts in multiple formats. An early patent for this type of measure was published in 1977.

There are also other styles of tape measures that have incorporated lasers and ultrasonic technology to measure the distance of an object with fairly reliable accuracy.

Tape measures often have black and red measurements on a yellow background as this is the optimal color combination for readability.

United States
Most tapes sold in the United States are inches- and feet-based. Some tapes have additional marks in the shape of small black diamonds, appearing every 19.2 in, used to mark out equal spacing for joists (five joists or trusses per US standard 8 ft length of building material). Many US tapes also have special markings every 16 in, which is a US standard interval for studs in construction: three spaces of 16 inches make exactly 4 ft which is the US commercial width of a sheet of plywood, gyproc or particle board.

The sale of dual Metric/US Customary scale measuring tapes is slowly becoming common in the United States. For example, in some Walmarts there are Hyper Tough brand tapes available in both US customary units and Metric units. Unlike US rulers, of which an overwhelming majority contain both centimeter and inch scales, tape measures are longer and thus traditionally have had scales in both inches and feet & inches. So, the inclusion of a metric scale requires the measuring device either to contain 3 scales of measurement or the elimination of one of the US Customary scales.

The use of millimeter only tape measures for housing construction is a part of the US metric building code. This code does not permit the use of centimeters. Millimeters produce whole (integer) numbers, reduce arithmetic errors, thus decreasing wastage due to such errors. The US made measuring tape shown on the right is interesting in that it is a "Reverse Measuring Tape", where the measurements can be read from right to left just as well as they can be read when the tape is used from left to right.

As a curious fact, in 1956, Justus Roe, a surveyor and tape-maker by trade, made the 600 ft gold-plated tape measure and, in a publicity gimmick, presented it to American professional baseball player Mickey Mantle.

Australia
The building industry was the first major industry grouping in Australia to complete its change to metric, being completed by January 1976.

In this the industry was grateful to the SAA (now Standards Australia) for the early production of the Standard AS 1155-1974 "Metric Units for Use in the Construction Industry", which specified the use of millimetres as the small unit for the metrication upgrade. In the adoption of the millimetre as the "small" unit of length for metrication (instead of the centimetre) the Metric Conversion Board leaned heavily on experience in the UK and within the ISO, where this decision had already been taken.

This was formally stated as follows: "The metric units for linear measurement in building and construction will be the metre (m) and the millimetre (mm), with the kilometre (km) being used where required. This will apply to all sectors of the industry, and the centimetre (cm) shall not be used. … the centimetre should not be used in any calculation and it should never be written down".

The logic of using the millimetre in this context was that the metric system had been so designed that there would exist a multiple or submultiple for every use. Decimal fractions would not have to be used. Since the tolerances on building components and building practice would rarely be less than one millimetre, the millimetre became the sub-unit most appropriate to this industry.

Because of this, those in the building/construction industry mainly use millimetre only tapes. While dual scale tapes showing both inches and centimetres are sold, these are mainly imported low-cost items (since it would be a restriction of trade to not allow their importation).

United Kingdom
Tape measures sold in the UK often have dual scales for metric and imperial units. Like the American tape measures described above, they also have markings every 16 in and 19.2 in.

Canada
Tape measures sold in Canada often have dual scales for metric and imperial units. All tapes in imperial units have markings every 16 in, but not at every 19.2 in. Home construction in Canada is largely, if not entirely, in imperial measure.

In surveying
Tapes are used in surveying for measuring horizontal, vertical or slope distances. Tapes are issued in various lengths and widths and graduated in a variety of ways. The measuring tapes used for surveying purposes are classified in 4 types according to the material from which they are manufactured:
 * 1) Linen or Cloth Tape is made of linen cloth with brass handle at zero end whose length is included in the tape length. It is very light and handy, but cannot withstand much wear and tear. So it cannot be used for accurate work. It is little used in surveying except for taking subsidiary measurements like offsets.
 * 2) Metallic Tape is reinforced with copper wires to prevent stretching or twisting of fibers. They are available in many lengths but tapes of 20 m and 30 m are more commonly used.
 * 3) Steel Tape is made of steel ribbon varying in width from 6 mm to 16 mm. It is available in lengths of 1, 2, 10, 30 and 50 meters. It cannot withstand rough usage and should therefore be used with great care.
 * 4) Invar Tape is made of invar, an alloy of steel (64%) and nickel (36%). It is 6 mm wide and is available in lengths of 30 m, 50 m and 100 m. It is costly and delicate and should be thus handled with great care.

Accuracy and standardisation
The accuracy of a tape measure is dependent on the ends of the tape and the markings printed onto the tape. The accuracy for the end of a retractable tape measure is dependent on the hook's sliding mechanism and thickness.

The European Commission (EC) has standardised a non-compulsory classification system for certifying tape measure accuracy, with certified tapes falling into one of three classes of accuracy: Classes I, II, and III. For example, under specific conditions the tolerances for 10m long tapes are:

 * Class I: accurate to ±1.10mm over 10m length
 * Class II: accurate to ±2.30mm over 10m length
 * Class III: accurate to ±4.60mm over 10m length

If a tape measure has been certified then the class rating is printed onto the tape alongside other symbols including the nominal length of the tape, the year of manufacture, the country of manufacture, and the name of the manufacturer. For retractable tapes, Class I are the most accurate and tend to be the most expensive, while Class II tapes are the most common class available.

title: Tape measure