Wafer level reliability testing: An idea whose time has come

Wafer level reliability testing has been nurtured in the DARPA supported workshops, held each autumn since 1982. The seeds planted in 1982 have produced an active crop of very large scale integration manufacturers applying wafer level reliability test methods. Computer Aided Reliability (CAR) is a new seed being nurtured. Users are now being awakened by the huge economic value of the wafer reliability testing technology

Molecular interconversion behaviour in comprehensive two-dimensional gas chromatography

Comprehensive two-dimensional gas chromatography (GC x GC) is shown to provide information on dynamic molecular behaviour (interconversion), with the interconversion process occurring on both columns in the coupled-column experiment. The experiment requires suitable adjustment of both experimental conditions and relative dimensions of each of the columns. In this case, a longer column than normally employed in GC x GC allows sufficient retention duration on the second column, which permits the typical plateau-shape recognised for the interconversion process to be observed. The extent of interconversion depends on prevailing temperature, retention time, and the phase type. Polyethylene glycol-based phases were found to result in high interconversion kinetics, although terephthalic acid-terminated polyethylene glycol had a lesser extent of interconversion. Much less interconversion was seen for phenyl-methylpolysiloxane and cyclodextrin phases. This suggests that for the oximes, interconversion largely occurs in the stationary phase. Examples of different extents of interconversion in both dimensions are shown, including peak coalescence on the first column with little interconversion on the second column

Preproglucagon neurons in the hindbrain have IL-6 Receptor α (IL-6Rα) and show Ca 2+ influx in response to IL-6

Neuronal circuits in the hypothalamus and hindbrain are of importance for control of food intake, energy expenditure, and fat mass. We have recently shown that treatment with exendin-4 (Ex-4), an analog of the proglucagon-derived molecule glucagon-like peptide 1 (GLP-1), markedly increases mRNA expression of the cytokine interleukin-6 (IL-6) in the hypothalamus and hindbrain and that this increase partly mediates the suppression of food intake and body weight by Ex-4. Endogenous GLP-1 in the central nervous system (CNS) is produced by preproglucagon (PPG) neurons of the nucleus of the solitary tract (NTS) in the hindbrain. These neurons project to various parts of the brain, including the hypothalamus. Outside the brain, IL-6 stimulates GLP-1 secretion from the gut and pancreas. In this study, we aim to investigate whether IL-6 can affect GLP-1-producing PPG neurons in the nucleus of the solitary tract (NTS) in mouse hindbrain via the ligand binding part of the IL-6 receptor, IL-6 receptor-α (IL-6Rα). Using immunohistochemistry, we found that IL-6Rα was localized on PPG neurons of the NTS. Recordings of these neurons in GCaMP3/GLP-1 reporter mice showed that IL-6 enhances cytosolic Ca2+ concentration in neurons capable of expressing PPG. We also show that the Ca2+ increase originates from the extracellular space. Furthermore, we found that IL-6Rα was localized on cells in the caudal hindbrain expressing immunoreactive NeuN (a neuronal marker) or CNP:ase (an oligodendrocyte marker). In summary, IL-6Rα is present on PPG neurons in the NTS, and IL-6 can stimulate these cells by increasing influx of Ca2+ to the cytosol from the extracellular space

Modular Palladium Bipyrazoles for the Isomerization of Allylbenzenes - Mechanistic Considerations and Insights into Catalyst Design and Activity, Role of Solvent, and Additive Effects

The catalytic activity of novel bidentate N,N-chelated palladium complexes derived from electron excessive, backbone fused 3,3′-bipyrazoles in the selective isomerization of terminal arylpropenoids and 1-alkenes is described. The catalysts are easily modified by appropriate wing tip substitution, while maintaining the same bulky, rigid unreactive aliphatic backbone. Eleven novel palladium complexes with different electronic and steric properties were investigated. Their performance in the palladium(II)-catalyzed isomerization of a series of substituted allylbenzenes was evaluated in terms of electronic as well as steric effects. Besides the clear finding of a general trend towards higher catalyst activity with more electron-donating properties of the coordinated N,N-bidentate ligands, we found that the catalytic process strongly depends on the choice of solvents and additives. Extensive solvent screening revealed that reactions run best in a 2:1 toluene-methanol mixture, with the alcohol employed being a crucial factor in terms of electronic and steric factors. A reaction mechanism involving a hydride addition–elimination mechanism starting with a palladium hydride species generated in situ in alcoholic solutions, as corroborated by experiments using deuterium labeled allylbenzene, seems to be most likely. The proposed mechanism is also supported by the observed reaction rate orders of κobs[cat.]≈1 (0.94), κobs [substrate]=0.20→1.0 (t→∞) and κobs [methanol]=−0.51 for the isomerization of allylbenzene. Furthermore, the influence of acid and base, as well as the role of the halide coordinated to the catalyst, are discussed. The system catalyzes the isomerization of allylbenzenes very efficiently yielding high E:Z selectivities under very mild conditions (room temperature) and at low catalyst loadings of 1 mol% palladium even in unpurified solvents. The integrity and stability of the catalyst system were confirmed by multiple addition reaction cycles, successive filtration and isolation experiments, and the lack of palladium black formation

Erosion characteristics and floc strenght of Athabasca river cohesive sediments: towards managing sediment-related issues

Purpose: Most of Canada’s tar sands exploitations are located in the Athabasca river basin. Deposited cohesive sediments in Athabasca river and tributaries are a potential source of PAHs in the basin. Erosional behavior of cohesive sediments depends not only of fluid turbulence but on sediments structure and particularly the influence of organic content. This research tries to describe this behavior in Athabasca river sediments. Methods: An experimental study of cohesive sediments dynamics in one of the tributaries, the Muskeg river, was developed in a rotating annular flume. Variation of the shear stress allowed the determination of erosional strength for beds with different consolidation periods. Particle size measurements were made with a laser diffraction device operated in a continuous flow through mode. Optical analyses of flocs (ESEM and TEM) were performed with samples taken at the end of the experiments. Results: An inverse relationship between suspended sediment concentration (SS) and the consolidation period was found. The differences are related in this research to the increasing organic content of the sediments with consolidation period. The particle size measurements during the experiments showed differences on floc strength that are also related to changing organic content during different consolidation periods. ESEM and TEM observations confirm the structural differences for beds with different consolidation periods. The effects of SFGL on floc structure and in biostabilization of the bed are discussed. Conclusions: It is recommended in this paper that consolidation period should be taken into account for the modeling of erosion of cohesive sediments in the Athabasca river. Relating to transport models of pollutants (PAHs) it is highly recommended to consider flocs organic content, particularly algae, in the resuspension module.Environment Canada, CONACY

Grapevine breeding under climate change: Applicability of a molecular marker linked to véraison

Viticulture is of high economic value. Traditional grapevine cultivars (Vitis vinifera L.) are used in adaptation to the climatic conditions from Northern to Southern European growing areas. However, the recent trend of global warming causes quality deficits due to a shift of the plant's development to earlier times in the year. As a consequence, premature ripening happens under warm temperatures and interferes with the balanced accumulation of sugars, acids, aroma profiles and berry coloration. Modern grapevine breeding is challenged to include the ripening behavior as an important trait (besides pathogen resistance and other characteristics) into the development of novel cultivars well suited for sustainable viticulture. Breeders nowadays apply molecular markers to follow the introgression of desired traits on the genetic level. Previous work has identified a molecular tag on grapevine chromosome 16 strongly linked to the time of véraison, the start of the second phase of berry ripening, in a segregating cross population. In this study we analyzed the transferability of this marker to a set of 36 grapevine cultivars commonly used in German viticulture. Association analysis verified the predictive character of the time point of véraison for maturation time and confirmed the diagnostic potential of the véraison-linked marker in this extended set of cultivars

Familie und Schule: zwei Orte der Erziehung.

B

Insufficient OPC migration into demyelinated lesions is a cause of poor remyelination in MS and mouse models

Failure of remyelination of multiple sclerosis (MS) lesions contributes to neurodegeneration that correlates with chronic disability in patients. Currently, there are no available treatments to reduce neurodegeneration, but one therapeutic approach to fill this unmet need is to promote remyelination. As many demyelinated MS lesions contain plentiful oligodendrocyte precursor cells (OPCs), but no mature myelinating oligodendrocytes, research has previously concentrated on promoting OPC maturation. However, some MS lesions contain few OPCs, and therefore, remyelination failure may also be secondary to OPC recruitment failure. Here, in a series of MS samples, we determined how many lesions contained few OPCs, and correlated this to pathological subtype and expression of the chemotactic molecules Semaphorin (Sema) 3A and 3F. 37 % of MS lesions contained low numbers of OPCs, and these were mostly chronic active lesions, in which cells expressed Sema3A (chemorepellent). To test the hypothesis that differential Sema3 expression in demyelinated lesions alters OPC recruitment and the efficiency of subsequent remyelination, we used a focal myelinotoxic mouse model of demyelination. Adding recombinant (r)Sema3A (chemorepellent) to demyelinated lesions reduced OPC recruitment and remyelination, whereas the addition of rSema3F (chemoattractant), or use of transgenic mice with reduced Sema3A expression increased OPC recruitment and remyelination. We conclude that some MS lesions fail to remyelinate secondary to reduced OPC recruitment, and that chemotactic molecules are involved in the mechanism, providing a new group of drug targets to improve remyelination, with a specific target in the Sema3A receptor neuropilin-1. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00401-013-1112-y) contains supplementary material, which is available to authorized users

A 'Regent' pedigree update: ancestors, offspring and their confirmed resistance loci

'Regent' is the fungal resistant grapevine cultivar with the highest acreage in Germany and an important resistance donor in international breeding programs. It carries the resistance loci Rpv3.1 as well as Ren3 and Ren9 against downy and powdery mildew, respectively. As the parents of 'Chambourcin', the resistant paternal ancestor of 'Regent', did not coincide with the breeder's information, the germplasm repository of JKI Geilweilerhof was screened to find the missing ancestors. SSR marker analysis revealed that 'Joannes Seyve 11369' and 'Plantet' are the true parents of 'Chambourcin' and not 'Seyve Villard 12-417' and 'Chancellor'. Furthermore, the origin of the resistance loci Ren3 and Ren9 could be traced back to the genotypes 'Seibel 4614' and 'Munson'. Since the breeder Hermann Jaeger mentioned 'Munson' as a direct descendant of Vitis aestivalis Michx. var. linsecomii (Buckley) L. H. Bailey and Vitis rupestris Scheele, one of these wild species might have been the donor of the loci