993 resultados para Large Extra Dimensions
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Was ist Arbeit? Ein notwendiges Übel, eine den Menschen erst zum Menschen machende Notwendigkeit, ein Mittel sich selbst zu verwirklichen, eine notwendige Struktur, die den Menschen gesund hält, ja sogar therapiert oder bloss eine unter vielen Möglichkeiten, mit dem Leben etwas anzufangen? Arbeit wurde schon immer mehrdeutig gefasst. Zwölf Autoren aus dem französischen und deutschen Kulturkreis diskutieren, was Arbeit ist und war. Die Beiträge aus Philosophie, Recht, Sozialwissenschaften, aber auch Kunstwissenschaften kreisen um vier wesentliche Spannungen des Begriffs Arbeit: die Arbeit der Frau, die Sichtbarkeit oder Sichtbarmachung der Arbeit, das Verhältnis von Arbeit zu anderen menschlichen Tätigkeiten, der Sinn und das Erleben der Arbeit mit dem allgegenwärtigen Stress, mit dem die heutige Arbeit verknüpft wird. Qu'est-ce que le travail? Un mal nécessaire, une nécessité pour faire des hommes des êtres humains, un moyen de se réaliser, une structure nécessaire qui maintient les êtres humains en santé, voire même les soigne, ou simplement une possibilité parmi d'autres de faire quelque chose de sa vie? Le terme de travail comprend un large éventail de significations. Douze auteurs de culture française et allemande discutent de ce qu'est le travail et de ce qu'il était. Les contributions issues de la philosophie, du droit, des sciences sociales, mais aussi des arts s'articulent autour de quatre dimensions essentielles du concept de travail: le travail des femmes, la visibilité ou la mise en évidence du travail, le lien entre le travail et les autres activités humaines, la recherche de sens et le vécu du travail avec le stress quotidien qui est aujourd'hui étroitement lié au travail.
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In this paper we included a very broad representation of grass family diversity (84% of tribes and 42% of genera). Phylogenetic inference was based on three plastid DNA regions rbcL, matK and trnL-F, using maximum parsimony and Bayesian methods. Our results resolved most of the subfamily relationships within the major clades (BEP and PACCMAD), which had previously been unclear, such as, among others the: (i) BEP and PACCMAD sister relationship, (ii) composition of clades and the sister-relationship of Ehrhartoideae and Bambusoideae + Pooideae, (iii) paraphyly of tribe Bambuseae, (iv) position of Gynerium as sister to Panicoideae, (v) phylogenetic position of Micrairoideae. With the presence of a relatively large amount of missing data, we were able to increase taxon sampling substantially in our analyses from 107 to 295 taxa. However, bootstrap support and to a lesser extent Bayesian inference posterior probabilities were generally lower in analyses involving missing data than those not including them. We produced a fully resolved phylogenetic summary tree for the grass family at subfamily level and indicated the most likely relationships of all included tribes in our analysis.
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In this procedure, subjects learn the spatial position of one hole out of many, that allows them to escape from a large open-field into their home cage. The arena is circular and can be rotated between trials so that no proximal landmark is permanently associated with the target hole. This task is thus similar to the Morris water maze procedure, since subjects must remember the position of the escape hole relative to extra-arena cues only. In addition it allows studying the importance of olfactory cues such as scent marks in or around a hole. Since the motivation is to reach home and the motor requirement is low, this task provides a useful alternative to the Morris place navigation task for studying spatial orientation in weanling or senescent rats. Examples are given showing that various behavioural parameters provide a good estimation as how subjects learn this task.
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The enhanced flow in carbon nanotubes is explained using a mathematical model that includes a depletion layer with reduced viscosity near the wall. In the limit of large tubes the model predicts no noticeable enhancement. For smaller tubes the model predicts enhancement that increases as the radius decreases. An analogy between the reduced viscosity and slip-length models shows that the term slip-length is misleading and that on surfaces which are smooth at the nanoscale it may be thought of as a length-scale associated with the size of the depletion region and viscosity ratio. The model therefore provides a physical interpretation of the classical Navier slip condition and explains why `slip-lengths' may be greater than the tube radius.
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AIMS: To compare the molecular profile of a series of sessile serrated adenomas (SSAs) and hyperplastic polyps (HPs), in order to distinguish these lesions, SSAs having a potential role in the genesis of serrated adenocarcinomas through a serrated pathway in which methylation plays a key role. METHODS AND RESULTS: Twelve HPs and sixteen SSAs of the right and left colon were investigated for microsatellite instability, DNA mismatch repair genes, p53, p16, and beta-catenin expression, MLH1 and p16 (CDKN2A) gene methylation, and KRAS and BRAF mutations. Both SSAs and HPs were microsatellite stable. MLH1 and MSH2 protein silencing, aberrant cytoplasmic expression and methylation of p16 were found to be exclusive to right-sided SSAs. The MLH1 promoter gene was frequently methylated in right-sided SSAs in contrast with HPs. Abnormal p53 and beta-catenin expression was present in both SSAs and HPs. BRAF and KRAS mutation were mutually exclusive, but KRAS mutation was present only in left-sided SSAs and HPs. CONCLUSIONS: HPs and SSAs may be related lesions. However, at least right-sided SSAs differ from left-sided SSAs and HPs in the occurrence of MLH1 and p16 methylation, supporting the hypothesis that SSAs could be precursors of serrated adenocarcinomas.
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We develop a mediation model in which firm size is proposed to affect the scale and quality of innovative output through the adoption of different decision styles during the R&D process. The aim of this study is to understand how the internal changes that firms undergo as they evolve from small to larger organizations affect R&D productivity. In so doing, we illuminate the underlying theoretical mechanism affecting two different dimensions of R&D productivity, namely the scale and quality of innovative output which have not received much attention in previous literature. Using longitudinal data of Spanish manufacturing firms we explore the validity of this mediation model. Our results show that as firms evolve in size, they increasingly emphasize analytical decision making, and consequently, large-sized firms aim for higher-quality innovations while small firms aim for a larger scale of innovative output.
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RYR1 mutations are the most common cause of structural congenital myopathies and may exhibit both dominant and recessive inheritance. Histopathological findings are variable and include central cores, multi-minicores, type 1 predominance/ uniformity, fibre type disproportion, increased internal nucleation and fatty and connective tissue. Until recently, diagnostic RYR1 sequencing was limited to mutational hotspots due to the large size of the gene. Since the introduction of full RYR1 sequencing in 2007 we have detected pathogenic mutations in 77 families: 39 had dominant inheritance and 38 recessive inheritance. In some cases with presumably recessive inheritance, only one heterozygous mutation inherited from an asymptomatic parent was identified. Of 28 dominant mutations, 6 were novel; 37 of the 59 recessive mutations were also novel. Dominant mutations were more frequently in recognized hotspot regions, while recessive mutations were distributed throughout the coding sequence. Dominant mutations were predominantly missense, whereas recessive mutations included many nonsense and splice mutations expected to result in reduced RyR1 protein. There was wide clinical variability in patients with both dominant and recessive inheritance. As a group, those with dominant mutations were generally more mildly affected than those with recessive inheritance, who had earlier onset and were weaker with more functional limitations. Extraocular muscle involvement was almost exclusively observed in the recessive group. Bulbar involvement was also more prominent in this group, resulting in a larger number requiring gastrostomy insertion. In conclusion, genomic sequencing of the entire RYR1 leads to the detection of many novel mutations, but may miss large genetic rearrangements in some cases. Assigning pathogenicity to novel mutations is often difficult and interpretation of genetic results in the context of clinical, histological and, increasingly, muscle MRI findings is essential.
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Specimens collected from the large intestine of the sidenecked turtle Podocnemis unifilis Troschel, 1848 in the region of Cuminá and Trombetas rivers near Pará, Brazil are assigned to a new genus and new species of the nematode superfamily Cosmocercoidea and family Atractidae and named Paraorientatractis semiannulata. The new genus is separated from the nearest genus Orientatractis by the funnelshaped mouth opening, the presence of 4 distinct lips, 4 papillae in the internal cycle, one on each lip margin, 2 lateral amphids with large amphidial pores and absence of submedian papillae. It is also separated from Orientatractis and Proatractis by the presence of striated lateral alae which curve dorsally extending from mid oesophagus to mid tail, the difference in size of the vulvar opening and the presence of large transverse ridges or semiannules on the dorsal surface. The new species can be separated from the species of the genera Orientatractis and Proatractis by the characters that distinguish the genera and the arrangement of the caudal papillae on the male. A host/parasite list for Podocnemis spp. is included
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This paper is to examine the proper use of dimensions and curve fitting practices elaborating on Georgescu-Roegen’s economic methodology in relation to the three main concerns of his epistemological orientation. Section 2 introduces two critical issues in relation to dimensions and curve fitting practices in economics in view of Georgescu-Roegen’s economic methodology. Section 3 deals with the logarithmic function (ln z) and shows that z must be a dimensionless pure number, otherwise it is nonsensical. Several unfortunate examples of this analytical error are presented including macroeconomic data analysis conducted by a representative figure in this field. Section 4 deals with the standard Cobb-Douglas function. It is shown that the operational meaning cannot be obtained for capital or labor within the Cobb-Douglas function. Section 4 also deals with economists "curve fitting fetishism". Section 5 concludes thispaper with several epistemological issues in relation to dimensions and curve fitting practices in economics.
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I study large random assignment economies with a continuum of agents and a finite number of object types. I consider the existence of weak priorities discriminating among agents with respect to their rights concerning the final assignment. The respect for priorities ex ante (ex-ante stability) usually precludes ex-ante envy-freeness. Therefore I define a new concept of fairness, called no unjustified lower chances: priorities with respect to one object type cannot justify different achievable chances regarding another object type. This concept, which applies to the assignment mechanism rather than to the assignment itself, implies ex-ante envy-freeness among agents of the same priority type. I propose a variation of Hylland and Zeckhauser' (1979) pseudomarket that meets ex-ante stability, no unjustified lower chances and ex-ante efficiency among agents of the same priority type. Assuming enough richness in preferences and priorities, the converse is also true: any random assignment with these properties could be achieved through an equilibrium in a pseudomarket with priorities. If priorities are acyclical (the ordering of agents is the same for each object type), this pseudomarket achieves ex-ante efficient random assignments.
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The control of endemic diseases has not attained the desired level of effectiveness in spite of the use of modern efficient thecnologies. The classic interventionist approach for the control of schistosomiasis is centered on systemic control of the snail hosts combined to large scale medical treatment and is usually carried out without social preocupation due to the assisted communities. It is easy to understand the interest and the ethical compromise of public health research while producing studies in which the biological and social determinants as well as the cultural components should be considered and also encompass the historical dimensions and symbolic representations. In face of the recent political decision in favor of decentralizations of health administration to municipal level, we suggest, in the present paper, an integrated approach for the epidemiological diagnosis of an endemic situation at local level. Theoretical and methodological aspects from both, epidemiology and anthropology are discussed. Epidemiological methods can be used to detect the dependent variables (those related to the human infection) and the independent variables (demographic, economic, sanitary and social). Another methodological approach of anthropological /etnographic nature can be conducted in order to make an articulation of the knowledge on the various dimensions or determinant levels of the disease. Mutual comprehension, between researchers and the people under investigation, on the dynamic transmission process would be relevant for a joint construction, at local level, of programmed actions for the control of endemic diseases. This would extend reflections on the health/disease process as a whole.
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Objectives: Gentamicin is among the most commonly prescribed antibiotics in newborns, but large interindividual variability in exposure levels exists. Based on a population pharmacokinetic analysis of a cohort of unselected neonates, we aimed to validate current dosing recommendations from a recent reference guideline (Neofax®). Methods: From 3039 concentrations collected in 994 preterm (median gestational age 32.3 weeks, range 24.2-36.5) and 455 term newborns, treated at the University Hospital of Lausanne between 2006 and 2011, a population pharmacokinetic analysis was performed with NONMEM®. Model-based simulations were used to assess the ability of dosing regimens to bring concentrations into targets: trough ≤ 1mg/L and peak ~ 8mg/L. Results: A two-compartment model best characterized gentamicin pharmacokinetics. Model parameters are presented in the table. Body weight, gestational age and postnatal age positively influence clearance, which decreases under dopamine administration. Body weight and gestational age influence the distribution volume. Model based simulations confirm that preterm infants need doses superior to 4 mg/kg, and extended dosage intervals, up to 48 hours for very preterm newborns, whereas most term newborns would achieve adequate exposure under 4 mg/kg q. 24 h. More than 90% of neonates would achieve trough concentrations below 2 mg/L and peaks above 6 mg/L following most recent guidelines. Conclusions: Simulated gentamicin exposure demonstrates good accordance with recent dosing recommendations for target concentration achievement.