238 research outputs found

    A General Existence Theorem of Zero Points

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    Let X be a non-empty, compact, convex set in R and an upper semi-continuous mapping from X to the collection of non-empty, compact, convex subsets in R. Its is well knwon that such a mapping has a stationary point in X, i.e. there exists a point in X satisfying that its image under has a non-empty intersection with the normal cone of X at the point. In case for every point in X it holds that the intersection of the image under with the normal cone of X at the point is either empty or contains the origin 0, then must have a zero point on X, i.e. there exists a point in X satisfying that 0 lies in the image of the point. Another well-known condition for the existence of a zero point follows from Ky Fan''s coincidence theorem, which says that if for every point in the intersection of the image with the tangent cone of X at the point is non-empty, the mapping must have a zero point. In this paper we extend all these existence results by giving a general zero point existence theorem, of which the two results are obtained as special cases. We also discuss what kind of solutions may exist when no further conditions are stated on the mapping . Finally, we show how our results can be used to establish several new intersection results on a compact, convex set.Economics ;

    Ergebnis der selektiven Verpaarung beim Entlebucher Sennenhund zur Reduktion der ureteralen Ektopie

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    Outcome of selective mating in the Entlebucher Mountain Dog for reduction of ureteral ectopia The Entlebucher Mountain Dog is predisposed to ureteral ectopia and associated diseases of the urinary tract as well as the kidneys, which can have severe to lethal consequences. Due to the clustered occurrence of clinical signs in 11 % of Entlebucher Mountain dogs in the absence of a genetic test for ureteral ectopia, screening was introduced in 2008 to allow phenotype-based breeding selection. The ureteral orifices of the dogs are visualized by ultrasound and existing urinary retention or urinary incontinence is documented. The diagnostic findings were evaluated centrally with assignment to one of five phenotypes depending on the localization of the ureteral orifices and the renal and ureteral shape. Breeding approval and mating restrictions are the responsibility of the respective breeding associations and predominantly Entlebucher Mountain Dogs with extravesical ectopic ureters and/or clinical signs were excluded from breeding. The effect of phenotype-based selective mating on the incidence of ureteral ectopia and its clinical signs, as well as possible factors influencing the expression of the phenotype, were determined in the birth cohorts after the introduction of screening. Analysis of the data set of 1456 phenotyped Entlebucher Mountain Dogs showed, that at 11 % versus 5 %, males were more frequently assigned to the extravesical phenotype than females. The effect of phenotype-based breeding selection was examined in a subpopulation consisting of phenotyped parents and their offspring (n = 876). The prevalence of the extravesical phenotype decreased from 24 % in the 2005 to 2007 birth cohorts to 1,4 % in the 2015 to 2017 birth cohorts. Since 2015 almost no Entlebucher Mountain Dogs with incontinence, hydroureter or hydronephrosis have been recorded. It was feared that the additional selection measures to control ureteral ectopia in the small Entlebucher Mountain Dog population would intensify the inbreeding increase. However, this has so far remained absent. Therefore, as long as no genetic test is available, it is recommended to continue phenotype-based breeding selection with exclusion of dogs with extravesical ureteral ectopia and/or hydroureter/hydronephrosis/urinary incontinence, while keeping an eye on the development of the inbreeding coefficient. Keywords: Ectopic ureter, Dog, Inbreeding, Phenotype, Breeding selection Deutsch Ergebnis der selektiven Verpaarung beim Entlebucher Sennenhund zur Reduktion der ureteralen Ektopie Der Entlebucher Sennenhund ist prädisponiert für die ureterale Ektopie und damit für assoziierte Erkrankungen der Harnwege sowie der Nieren, was schwerwiegende bis letale Folgen haben kann. Aufgrund des gehäuften Auftretens klinischer Symptome bei 11 % der Entlebucher Sennenhunde wurde in Ermangelung eines Gentests auf ureterale Ektopie 2008 ein Screening eingeführt, um eine Phänotyp-basierte Zuchtselektion zu ermöglichen. Die Uretermündungen der Hunde werden in der Regel mittels Ultraschall lokalisiert und bestehender Harnrückstau oder Harninkontinenz wird dokumentiert. Die Befundung erfolgte zentral mit einer Zuordnung zu einem von fünf Phänotypen in Abhängigkeit von der Lokalisation der Uretermündungen sowie der Nieren – und Ureterengestalt. Die Zuchtzulassung und Verpaarungsbeschränkungen obliegen den jeweiligen Zuchtverbänden, wobei überwiegend Entlebucher Sennenhunde mit extravesikal ektopischen Ureteren und/oder klinischen Symptomen von der Zucht ausgeschlossen wurden. Die Auswirkung der Phänotyp-basierten selektiven Verpaarung auf das Auftreten der ureteralen Ektopie und deren klinischen Symptome sowie mögliche Einflussfaktoren auf die Ausprägung des Phänotyps wurden in den Geburtsjahren nach Einführung des Screenings ermittelt. Die Analyse des Datensatzes mit 1456 phänotypisierten Entlebucher Sennenhunden zeigte, dass mit 11 % versus 5 % Rüden häufiger als Hündinnen dem extravesikalen Phänotyp zugeteilt wurden. Die Auswirkung der Phänotyp-basierten Zuchtselektion wurde an einer Teilpopulation, bestehend aus phänotypisierten Elterntieren und ihren Nachkommen (n = 876), untersucht. Die Prävalenz des extravesikalen Phänotyps nahm von 24 % bei den Geburtsjahren 2005 bis 2007 auf 1,4 % bei den Geburtsjahren 2015 bis 2017 ab. Seit 2015 wurden nahezu keine Entlebucher Sennenhunde mehr mit Inkontinenz, Hydroureter oder Hydronephrose erfasst. Befürchtet wurde, dass die zusätzlichen Selektionsmassnahmen zur Bekämpfung der ureteralen Ektopie in der kleinen Entlebucher Sennenhundepopulation den Inzuchtanstieg verstärken würde. Dies blieb bisher jedoch aus. Daher wird, solange kein genetischer Test zur Verfügung steht, empfohlen, die Phänotyp-basierte Zuchtselektion mit Ausschluss von Hunden mit extravesikaler ureteraler Ektopie und/oder Hydroureter/Hydronephrose/Harninkontinenz vorerst weiterzuführen und gleichzeitig die Entwicklung des Inzuchtkoeffizienten im Auge zu behalten. Schlüsselwörter: Ektopischer Ureter, Hund, Inzucht, Phänotyp, Zuchtselektion Français Résultat de l’accouplement sélectif chez le bouvier de l’Entlebuch pour réduire l’ectopie urétérale Le Bouvier de l’Entlebuch est prédisposé à l’ectopie urétérale et aux maladies associées des voies urinaires ainsi que des reins, ce qui peut entraîner des conséquences fatales. En raison de l’apparition de signes cliniques chez 11 % des chiens et en l’absence d’un test génétique pour l’ectopie urétérale, un dépistage a été introduit en 2008 pour permettre une sélection d’élevage basée sur le phénotype. Les orifices urétraux des chiens ont été visualisés par échographie et la rétention ou l’incontinence urinaire existante documentée. Les résultats du diagnostic ont été évalués de manière centralisée avec attribution à l’un des cinq phénotypes en fonction de la localisation des orifices urétéraux ainsi que de la forme des reins et des uretères. L’approbation pour la reproduction et les restrictions d’accouplement relèvent de la responsabilité des associations d’élevage respectives et les bouviers de l’Entlebuch présentant des uretères ectopiques extravésicaux et/ou des signes cliniques ont majoritairement été exclus de la reproduction. L’effet de cet accouplement sélectif basé sur le phénotype sur l’incidence de l’ectopie urétérale et de ses signes cliniques ainsi que les facteurs possibles influençant l’expression du phénotype ont été déterminés dans les cohortes de naissance après l’introduction du dépistage. L’analyse de l’ensemble des données de 1456 Bouviers de l’Entlebuch phénotypés a montré que, à 11 % contre 5 %, les mâles étaient plus fréquemment affectés au phénotype extravésical que les femelles. L’effet de la sélection d’élevage basée sur le phénotype a été examiné dans une sous-population composée de parents phénotypés et de leur progéniture (n = 876). La prévalence du phénotype extravésical est passée de 24 % dans les cohortes de naissance de 2005 à 2007 à 1,4 % dans les cohortes de naissance de 2015 à 2017. Depuis 2015, presque aucun bouvier d’Entlebuch présentant une incontinence, un hydrouretère ou une hydronéphrose n’a été enregistré. Une possible augmentation de la consanguinité due aux mesures de sélection supplémentaires visant à contrôler l’ectopie urétérale ne s’est pas produite. Par conséquent, tant qu’aucun test génétique n’est disponible, il est recommandé de poursuivre la sélection d’élevage basée sur le phénotype avec exclusion des chiens présentant une ectopie urétérale extravésicale et/ou une hydrouretère/hydronéphrose/incontinence urinaire, tout en surveillant l’évolution du coefficient de consanguinité. Mots-clés: auretère ectopique, chien, consanguinité, phénotype, sélection d’élevage Italiano Risultato dell'accoppiamento selettivo nel cane da montagna Entlebuch per ridurre l'ectopia ureterale Il bovaro dell’Entlebuch è predisposto all’ectopia ureterale e quindi alle malattie che sono correlate al tratto urinario e renale con possibili conseguenze letali. A causa della frequente comparsa di segni clinici nell’11 % dei cani e in assenza di un test genetico per l’ectopia ureterale, nel 2008 è stato introdotto uno screening per consentire la selezione fenotipica dei riproduttori. Gli orifizi ureterali dei cani sono solitamente localizzato tramite ecografia e viene documentata la presenza di ritenzione o incontinenza urinaria. I risultati sono stati valutati in modo centralizzato e si è assegnato il risultato a uno dei cinque fenotipi a seconda della localizzazione degli orifizi ureterali e della forma dei reni e degli ureteri. L’autorizzazione all’allevamento e le restrizioni all’accoppiamento sono di competenza delle rispettive associazioni di allevatori e i bovari dell’Entlebuch con ureteri ectopici extravescicali e/o con segni clinici sono stati prevalentemente esclusi dalla riproduzione. L’effetto dell’accoppiamento selettivo, basato sul fenotipo per rapporto all’incidenza dell’ectopia ureterale e dei suoi segni clinici, nonché dei possibili fattori che influenzano l’espressione del fenotipo, è stato determinato nelle coorti di nascita dopo l’introduzione dello screening. L’analisi del set di dati di 1456 bovari dell’Entlebuch fenotipizzati ha dimostrato che, con una percentuale dell’11 % rispetto al 5 %, i maschi erano più frequentemente assegnati al fenotipo extravescicale rispetto alle femmine. L’effetto della selezione riproduttiva basata sul fenotipo è stato esaminato in una subpopolazione composta da genitori fenotipizzati e dalla loro discendenza (n = 876). La prevalenza del fenotipo extravescicale è diminuita dal 24 % nelle coorti di nascita dal 2005 al 2007 all’1,4 % nelle coorti di nascita dal 2015 al 2017. Dal 2015 non sono stati registrati quasi più bovari dell’Entlebuch con incontinenza, idrouretere o idronefrosi. Non si è riscontrato un possibile aumento della consanguineità dovuto alle misure di selezione aggiuntive per controllare l’ectopia ureterale. Pertanto, finché non è disponibile un test genetico, si raccomanda di continuare la selezione fenotipica con l’esclusione dei cani con ectopia ureterale extravescicale e/o idrouretere/idronefrosi/incontinenza urinaria, facendo particolare attenzione all’andamento del coefficiente di consanguineità. Parole chiavi: Uretere ectopico, cane, consanguineità, fenotipo, selezione riproduttiv

    Inheritance of porcine receptors for enterotoxigenic Escherichia coli with fimbriae F4ad and their relation to other F4 receptors

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    Enteric Escherichia coli infections are a highly relevant cause of disease and death in young pigs. Breeding genetically resistant pigs is an economical and sustainable method of prevention. Resistant pigs are protected against colonization of the intestine through the absence of receptors for the bacterial fimbriae, which mediate adhesion to the intestinal surface. The present work aimed at elucidation of the mode of inheritance of the F4ad receptor which according to former investigations appeared quite confusing. Intestines of 489 pigs of an experimental herd were examined by a microscopic adhesion test modified in such a manner that four small intestinal sites instead of one were tested for adhesion of the fimbrial variant F4ad. Segregation analysis revealed that the mixed inheritance model explained our data best. The heritability of the F4ad phenotype was estimated to be 0.7±0.1. There are no relations to the strong receptors for variants F4ab and F4ac. Targeted matings allowed the discrimination between two F4ad receptors, that is, a fully adhesive receptor (F4adRFA) expressed on all enterocytes and at all small intestinal sites, and a partially adhesive receptor (F4adRPA) variably expressed at different sites and often leading to partial bacterial adhesion. In pigs with both F4ad receptors, the F4adRPA receptor is masked by the F4adRFA. The hypothesis that F4adRFA must be encoded by at least two complementary or epistatic dominant genes is supported by the Hardy-Weinberg equilibrium statistics. The F4adRPA receptor is inherited as a monogenetic dominant trait. A comparable partially adhesive receptor for variant F4ab (F4abRPA) was also observed but the limited data did not allow a prediction of the mode of inheritance. Pigs were therefore classified into one of eight receptor phenotypes: A1 (F4abRFA/F4acR+/F4adRFA); A2 (F4abRFA/F4acR+/F4adRPA); B (F4abRFA/F4acR+/F4adR−); C1 (F4abRPA/F4acR−/F4adRFA); C2 (F4abRPA/F4acR−/F4adRPA); D1 (F4abR−/F4acR−/F4adRFA); D2 (F4abR−/F4acR−/F4adRPA); E (F4abR−/F4acR−/F4adR−

    Dual origins of dairy cattle farming - evidence from a comprehensive survey of European Y-chromosomal variation

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    BACKGROUND: Diversity patterns of livestock species are informative to the history of agriculture and indicate uniqueness of breeds as relevant for conservation. So far, most studies on cattle have focused on mitochondrial and autosomal DNA variation. Previous studies of Y-chromosomal variation, with limited breed panels, identified two Bos taurus (taurine) haplogroups (Y1 and Y2; both composed of several haplotypes) and one Bos indicus (indicine/zebu) haplogroup (Y3), as well as a strong phylogeographic structuring of paternal lineages. METHODOLOGY AND PRINCIPAL FINDINGS: Haplogroup data were collected for 2087 animals from 138 breeds. For 111 breeds, these were resolved further by genotyping microsatellites INRA189 (10 alleles) and BM861 (2 alleles). European cattle carry exclusively taurine haplotypes, with the zebu Y-chromosomes having appreciable frequencies in Southwest Asian populations. Y1 is predominant in northern and north-western Europe, but is also observed in several Iberian breeds, as well as in Southwest Asia. A single Y1 haplotype is predominant in north-central Europe and a single Y2 haplotype in central Europe. In contrast, we found both Y1 and Y2 haplotypes in Britain, the Nordic region and Russia, with the highest Y-chromosomal diversity seen in the Iberian Peninsula. CONCLUSIONS: We propose that the homogeneous Y1 and Y2 regions reflect founder effects associated with the development and expansion of two groups of dairy cattle, the pied or red breeds from the North Sea and Baltic coasts and the spotted, yellow or brown breeds from Switzerland, respectively. The present Y1-Y2 contrast in central Europe coincides with historic, linguistic, religious and cultural boundaries.Penedo, Lenstra mail

    Effect of Key2Teach on Dutch teachers' relationships with students with externalizing problem behavior:A randomized controlled trial

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    The teacher-student relationship plays an important role in the academic and behavioral development of primary school children with externalizing problem behavior. However, such problem behavior often threatens the quality of the teacher-student relationship. Teacher-focused coaching intervention Key2Teach aims to improve elements of the relationship between teachers and students with externalizing problem behavior and consists of two phases and four building blocks. This intervention provides primary school teachers with insight into their mental representation of the relationship and opportunities to practice functional interaction skills. In a randomized controlled trial (RCT), effects of Key2Teach on different aspects of the relationship between teachers and students with externalizing problem behavior were examined. In two cohorts, 103 dyads consisting of a teacher and a student with externalizing problem behavior in grades 3-6 were assessed three times during a school year. Fifty-three dyads received the intervention (intervention group), whereas 50 dyads received no intervention (control group). Data were collected on teacher-reported teacher-student closeness and conflict, and on teacher interaction skills in various domains. Results show a significant increase in closeness and a decrease in conflict as a result of Key2Teach, with substantial effect sizes. No effects on teacher interaction skills were found. This study indicates that Key2Teach may help teachers to improve elements of the relationship they have with students with externalizing problem behavior. Implications for practice and future research are discussed

    Why Gender and Age Prediction from Tweets is Hard: Lessons from a Crowdsourcing Experiment

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    There is a growing interest in automatically predicting the gender and age of authors from texts. However, most research so far ignores that language use is related to the social identity of speakers, which may be different from their biological identity. In this paper, we combine insights from sociolinguistics with data collected through an online game, to underline the importance of approaching age and gender as social variables rather than static biological variables. In our game, thousands of players guessed the gender and age of Twitter users based on tweets alone. We show that more than 10% of the Twitter users do not employ language that the crowd associates with their biological sex. It is also shown that older Twitter users are often perceived to be younger. Our findings highlight the limitations of current approaches to gender and age prediction from texts
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