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Comprend des références bibliographiques

Classification of Regional Labour Markets At the NUTS3 Level in Germany

In many countries labour market policy has to deal with fairly large and persistent regional labour market disparities. In the case of Germany, parts of the country are affected by a deep unemployment crisis whereas others show nearly full employment. Since these disparities cannot be reduced to only one dimension a classification system of labour markets was developed. The criterion of this system was the identification of the "regional disadvantage" for the success of labour market policy. This new classification is at the level of districts (NUTS 3 regions). To optimise the results a two-step classification method was applied. The first step included regression analyses to identify the exogenous determinants of the success of labour market policy. In the second step, different types of labour markets are determined from a specific variant of cluster analysis which used the weighted variables identified as significant in the first step. This classification is used in the Federal Employment Agency for benchmarking reasons. Besides that, the new classification obtained could also be employed in research, for example in the evaluation of labour market policy

Translation controls the expression level of a chimaeric reporter gene

Transcriptional and translational fusions between the reading frame of the β-D-glucuronidase gene (gusA) and the 2′ as well as the 1′ promoter of mannopine synthase (mas), a TR locus of Agrobacterium tumefaciens, were made. The expression of these constructs was studied in the transgenic F1 offspring of independent tobacco transformants at the protein level by assaying for GUS activity and western blot analysis of the GUS protein and at the steady-state mRNA level. In leaves, stems and roots no correlation was found between steady-state levels of GUS mRNA and enzyme activity. In older tissues significantly higher GUS activities were found. This is explained by the stable character of the GUS protein together with an accumulation of protein upon ageing. Three to ten times higher GUS activities were found for in vitro grown plants than for greenhouse-grown plants of the same offspring, despite similar levels of GUS mRNA. Roots from in vitro grown plants display three to ten times higher GUS activities than stems and leaves. In transgenic plants grown in vitro, containing a translational fusion with two AUGs in phase, the initiation of translation in leaf material occurred at both AUGs. Initiation of translation at the first AUG, however, was ten times more frequent. In contrast, initiation in roots from in vitro grown plants occurred exclusively at the second AUG

Policy Analysis of Rural Development Strategy in Mexico: Creation and Management of Infrastructure Systems

This thesis explores rural development strategy in Mexico within the context of infrastructure development. It finds that although the tenants of decentralization and neoliberalism on which the strategy is based are conducive to gains in productivity, equity, and environmental sustainability in rural Mexico, the current government apparatus creates a number of market failures which limit the beneficial potential of the development strategy. Lessons learned from the Mexican experience should be applied in other contexts for development strategies

Higher order glass-transition singularities in colloidal systems with attractive interactions

The transition from a liquid to a glass in colloidal suspensions of particles interacting through a hard core plus an attractive square-well potential is studied within the mode-coupling-theory framework. When the width of the attractive potential is much shorter than the hard-core diameter, a reentrant behavior of the liquid-glass line, and a glass-glass-transition line are found in the temperature-density plane of the model. For small well-width values, the glass-glass-transition line terminates in a third order bifurcation point, i.e. in a A_3 (cusp) singularity. On increasing the square-well width, the glass-glass line disappears, giving rise to a fourth order A_4 (swallow-tail) singularity at a critical well width. Close to the A_3 and A_4 singularities the decay of the density correlators shows stretching of huge dynamical windows, in particular logarithmic time dependence.Comment: 19 pages, 12 figures, Phys. Rev. E, in prin

Nonergodicity transitions in colloidal suspensions with attractive interactions

The colloidal gel and glass transitions are investigated using the idealized mode coupling theory (MCT) for model systems characterized by short-range attractive interactions. Results are presented for the adhesive hard sphere and hard core attractive Yukawa systems. According to MCT, the former system shows a critical glass transition concentration that increases significantly with introduction of a weak attraction. For the latter attractive Yukawa system, MCT predicts low temperature nonergodic states that extend to the critical and subcritical region. Several features of the MCT nonergodicity transition in this system agree qualitatively with experimental observations on the colloidal gel transition, suggesting that the gel transition is caused by a low temperature extension of the glass transition. The range of the attraction is shown to govern the way the glass transition line traverses the phase diagram relative to the critical point, analogous to findings for the fluid-solid freezing transition.Comment: 11 pages, 7 figures; to be published in Phys. Rev. E (1 May 1999

Dynamic orifice area variations in functional mitral regurgitation: In vivoreproduction and mechanistic insights

Aims: The spinocerebellar ataxia type 2 (SCA2), type 3 (SCA3) and type 7 (SCA7) are clinically characterized by progressive and severe ataxic symptoms, dysarthria, dysphagia, oculomotor impairments, pyramidal and extrapyramidal manifestations and sensory deficits. Although recent clinical studies reported additional disease signs suggesting involvement of the brainstem auditory system, this has never been studied in detail in SCA2, SCA3 or SCA7. Methods: We performed a detailed pathoanatomical investigation of unconventionally thick tissue sections through the auditory brainstem nuclei (that is, nucleus of the inferior colliculus, nuclei of the lateral lemniscus, superior olive, cochlear nuclei) and auditory brainstem fibre tracts (that is, lateral lemniscus, trapezoid body, dorsal acoustic stria, cochlear portion of the vestibulocochlear nerve) of clinically diagnosed and genetically confirmed SCA2, SCA3 and SCA7 patients. Results: Examination of unconventionally thick serial brainstem sections stained for lipofuscin pigment and Nissl material revealed a consistent and widespread involvement of the auditory brainstem nuclei in the SCA2, SCA3 and SCA7 patients studied. Serial brainstem tissue sections stained for myelin showed loss of myelinated fibres in two of the auditory brainstem fibre tracts (that is, lateral lemniscus, trapezoid body) in a subset of patients. Conclusions: The involvement of the auditory brainstem system offers plausible explanations for the auditory impairments detected in some of our and other SCA2, SCA3 and SCA7 patients upon bedside examination or neurophysiological investigation. However, further clinical studies are required to resolve the striking discrepancy between the consistent involvement of the brainstem auditory system observed in this study and the comparatively low frequency of reported auditory impairments in SCA2, SCA3 and SCA7 patients

Comparative simulation study of colloidal gels and glasses

Using computer simulations, we identify the mechanisms causing aggregation and structural arrest of colloidal suspensions interacting with a short-ranged attraction at moderate and high densities. Two different non-ergodicity transitions are observed. As the density is increased, a glass transition takes place, driven by excluded volume effects. In contrast, at moderate densities, gelation is approached as the strength of the attraction increases. At high density and interaction strength, both transitions merge, and a logarithmic decay in the correlation function is observed. All of these features are correctly predicted by mode coupling theory

ccl44 is essential for normal embryonic hematopoiesis

Hematopoiesis is the process of blood formation dependent on the continual need for blood cell replenishment throughout the life of the organism. Capable of self-renewal and differentiation into daughter cells, hematopoietic stem and progenitor cells (HSPCs) differentiate into all the mature blood cells in the body. By studying the molecular pathways responsible for this differentiation, we can better understand and treat a multitude of blood diseases, which often arise from defects in these processes. The zebrafish (Danio rerio) is an ideal model organism to use for the study of hematopoiesis because their blood development is similar to humans and they have high fecundity which allows us to look at a larger sample pool in a shorter time frame. In addition, the embryos are transparent and develop outside the body making manipulation and observation easier. Through RNA sequencing, our laboratory has identified the top 100 genes integral to HSPC maintenance identified in the three lines of zebrafish supportive stromal cells. One such gene was chemokine (C-C motif) ligand 44, ccl44. Investigation with morpholinos showed a reduction in erythroid and myeloid cells which were then successfully rescued with co-injection of mRNAs. To validate these findings, we also performed experiments using the CRISPR/Cas9 system. Zebrafish with fluorescently labeled myeloid and erythroid cells were injected with ccl44 guide RNA that we produced in the laboratory along with Cas9 protein. The knockout of full-length ccl44 gene expression was confirmed with RT-PCR. Sanger sequencing was utilized to confirm indels in the ccl44 genomic sequence. In mutant animals, a decrease in myeloid and erythroid cells was observed with fluorescent microscopy and flow cytometry. Additionally, a decrease in hematopoietic stem and progenitor cells was observed utilizing methylcellulose assays. Many phenotypic defects were also seen in the mutated embryos, including shortened tail length and spinal curvature, consistent with a defect in mesoderm patterning. Elucidating the role of ccl44 in hematopoiesis should help inform us about the evolution of the vertebrate hematopoietic system