130 research outputs found
Zyklische Druck- und Torsionsbelastung an Schafsknochen mit ESIN-Implantaten
Knochenbrüche werden immer öfter chirurgisch statt konservativ behandelt, da die Heilung schneller verläuft und der Knochen früher wieder belastet werden kann.
Gut geeignet für Kinder sind ESIN- Implantate (Elastisch Stabile Intramedulläre Nagelung). Ihre elastischen Eigenschaften stimulieren die Kallusbildung, gleichzeitig wird der Bruch aber auch gut stabilisiert und der Knochen gestützt.
Nach der Heilung müssen die Implantate in einer zweiten Operation jedoch wieder entfernt werden, um das noch nicht abgeschlossene Wachstum des Kindes nicht zu behindern.
Im Zuge des Projektes BRIC (BioResorbable Implants for Children) sollen ESIN-Implantate entwickelt werden, die sich bis zur Heilung des Bruches selbst auflösen und vom Körper abgebaut werden.
An der Entwicklung eines bioresorbierbaren Materials, das aufgrund seiner biomechanischen Eigenschaften und seiner Abbauprodukte auch für Kinder geeignet ist, wird derzeit gearbeitet.
In der vorliegenden Arbeit wird eine Methode zur Ermittlung der biomechanischen Eigenschaften beschrieben. In eine Prüfmaschine werden Schafstibiae, die mit ESIN und einem künstlichen Bruchspalt versehen sind, eingespannt. Sie werden über 5000 Zyklen mit einem bestimmten Druck und Drehmoment simultan belastet. Die Dauer der zyklischen Belastung entspricht jener, die bis zur Heilung im kindlichen Körper auftritt.
Werden die festgelegten Grenzwerte während der Messung unter- oder überschritten, bricht der Versuch frühzeitig ab. In diesem Fall kann man davon ausgehen, dass das Implantat versagt hat und seine Funktion nicht mehr erfüllt.
Aus den erhaltenen Daten können verschiedene Eigenschaften, wie die Steifigkeit, die elastische oder die plastische Deformation, des Implantats abgelesen werden.
In folgenden Studien sollen mit dem beschriebenen Verfahren verschiedene ESIN-Systeme, mit und ohne Verriegelung, getestet und verglichen werden.More and more often bone fractures are treated surgically instead of conservative treatment because the healing proceeds much faster and the post-operatively loading can be done almost immediately.
ESIN (Elastic Stable Intramedullary Nailing) is most suitable for children. The osteosynthesis' elastic characteristics stimulate the callus formation and stabilise the fracture at the same time.
Since bone growth in children is incomplete and implants could interfere with further development the implants have to be removed in another operation.
The BRIC Project (Bio Resorbable Implants for Children) intends to develop a kind of ESIN made of bioresorbable material that dissolves and gets absorbed by the body until the healing process is completed.
Existing bioresorbable implants can only be used for adults. Due to the different needs of children there has to be adaptation in material and biomechanical properties of the implants.
In this thesis, a method to determine and describe these biomechanical properties is shown. Therefore ESIN and an artificial fracture are added to sheep tibia which is clamped to a testing machine.
In this test device the bone is simultaneously and cyclical loaded with axial and torsional forces. The duration of 5000 cycles is equivalent to the healing process in bone fractures of children. If the value exceeds the determined limit the test ends automatically. In this case it is clear that the implant has failed and doesn't fulfill its purpose.
Certain characteristics like stiffness and elastic or plastic deformation can be assessed of the obtained data.
In following studies the described method will be used to test and compare different ESIN implants and indicate whether end caps improve the system or not
The nature and use of proto-languages
While it is true that languages related through (as one says) common descent are derived from a common ancestor language, this idiom, if unattested and available only in the form of a reconstructed proto-language, has only a limited degree of realism. The manner in which linguistic reconstruction proceeds, the lack of truly quantitative criteria in determining type and degree of linguistic relatedness, and the necessity to arrive at an entirely uniform linguistic construct are all apt to deliver a distorted or false view of the proto-language. Indeed its very existence may be questionable, especially if it cannot be supported by non-linguistic evidence; this applies in particular to intermediate reconstructed proto-languages like Proto-Italo-Keltic, Proto-West-Germanic, Proto-Ibero-Romanic, which are but way-stations on the road to the ultimate parent language. It is therefore suggested that all proto-languages be considered creations for the convenience of linguistic investigation and for the purpose of delving into an otherwise inaccessible linguistic past, but that no claim should be made for their being viewed and dealt with as real languages in any sense of the word, unless and until there accrues sufficient non-linguistic evidence for fixing them in time and place and for associating them with an anthropologically, archaeologically, or historically identifiable society. The reverse process, that is, the creation of a society to go with an unattested, reconstructed proto-language, is altogether improper.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32387/1/0000462.pd
Homo loquens: An ethological view
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32845/1/0000221.pd
The functions of past tenses: Greek, Latin, Italian, French
Latin grammarians describing their language (or laying down rules for the proper use of it) owe much to their Greek predecessors, notably Dionysius Thrax (c. 170-90 B.C.), whose rules they sought to replicate and whose terminology they translated. But since Latin is different in structure from Greek, and since in particular it does not have the same number of past tenses as Greek, the syntax of its tenses is not congruent with that of Greek either. And if the names of Greek tenses indicated in some measure, however awkwardly, their function, translation of these names into Latin could not but be misleading. Since also modern grammarians often base themselves on this Graeco-Roman grammatical tradition, the rules for the use of tenses and the names they devised in imitation of that tradition are less than satisfactory and at times confusing, whether they pertain to the temporal or the so-called aspectual function of the past tenses.It is argued that language in general, and tenses in particular, do not always or necessarily present faithfully the physical reality but rather re-present it, filtered, as it were, through the speaker. In this manner, the use of one or the other past tense evokes that perception of the action expressed by the verb which the speaker wants the hearer to receive. It follows that the same reality can be stated by, say, either the "imperfect" or the "past" (simple or compound) in Italian or French, depending on whether the speaker wishes to have the hearer contemplate what goes on as a picture (though movement may be involved), or whether he wants to report to the speaker the occurrence of an event, or of a series of events. In the first case, the verb answers the question -- posed or implied -- "What was the state? What were the circumstances?"; in the second, the question is "What happened? What happened next?".Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24684/1/0000103.pd
Differential processing of consonants and vowels in the auditory modality: A cross-linguistic study
International audienceFollowing the proposal by Nespor, Peña, and Mehler (2003) that consonants are more important in constraining lexical access than vowels, New, Araújo, and Nazzi (2008) demonstrated in a visual priming experiment that primes sharing consonants (jalu-JOLI) facilitate lexical access while primes sharing vowels do not (vobi-JOLI). The present study explores if this asymmetry can be extended to the auditory modality and whether language input plays a critical role as developmental studies suggest. Our experiments tested French and English as target languages and showed that consonantal information facilitated lexical decision to a greater extent than vocalic information, suggesting that the consonant advantage is independent of the language’s distributional properties. However, vowels are also facilitatory, in specific cases, with iambic English CVCV or French CVCV words. This effect is related to the preservation of the rhyme between the prime and the target (here, the final vowel), suggesting that the rhyme, in addition to consonant information and consonant skeleton information is an important unit in auditory phonological priming and spoken word recognition
Formations of the perfect in the Sabellic languages with the Italic and Indo-European background
InfoSyll: A Syllabary Providing Statistical Information on Phonological and Orthographic Syllables
here is now a growing body of evidence in various languages supporting the claim that syllables are functional units of visual word processing. In the perspective of modeling the processing of polysyllabic words and the activation of syllables, current studies investigate syllabic effects with subtle manipulations. We present here a syllabary of the French language aiming at answering new constraints when designing experiments on the syllable issue. The InfoSyll syllabary provides exhaustive characteristics and statistical information for each phonological syllable (e.g. /fi/) and for its corresponding orthographic syllables (e.g. fi, phi, phy, fee, fix, fis). Variables such as the type and token positional frequencies, the number and frequencies of the correspondences between orthographic and phonological syllables are provided. As discussed, such computations should allow precise controls, manipulations and quantitative descriptions of syllabic variables in the field of psycholinguistic research.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
Phonème et graphème : un parallèle
Pulgram Ernst. Phonème et graphème : un parallèle . In: Archives et documents de la Société d'histoire et d'épistémologie des sciences du langage, Première série, n°5, 1984. pp. 35-45
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