A simple atomic beam oven with a metal thermal break

We report the design and construction of a simple, easy to machine high-temperature oven for generating an atomic beam in laser cooling experiments. This design eliminates the problem of thermal isolation of the oven region from the rest of the vacuum system without using a glass or ceramic thermal break. This design simplifies the construction and operation of high-temperature ovens for elements having low vapor pressure. We demonstrate the functionality of such a source for Strontium (Sr) atoms. We generate a high flux of Sr atoms for use in laser cooling and trapping experiments. The optimization of the design of the metal thermal break is done using a finite element analysis.Comment: 5 pages,6 figure

COMPARATIVE STUDY OF MICROALBUMINURIA AND GLYCATED HEMOGLOBIN LEVELS IN TYPE 2 DIABETIC COMPLICATIONS

ABSTRACTObjective: Microalbuminuria occurs when the kidney leaks a small amount of albumin into the urine or when there is an abnormally high permeabilityfor albumin in the renal glomerulus. Microalbuminuria is a powerful risk factor of cardiovascular disease and for the presence and severity of diabeticretinopathy and neuropathy. The aim of this study is to compare the levels of microalbumin and glycated hemoglobin (HbA1c) levels in Type 2 diabeticcomplications.Methods: The study includes 100 patients with Type 2 diabetes mellitus visiting the diabetic out-patient department patients with complications,such as hypertension, retinopathy, neuropathy, and cardiovascular complication, was diagnosed based on history and clinical examination and relatedinvestigations. Microalbuminuria levels and HbA1c levels are compared in patients with complications (subjects) of Type 2 diabetes mellitus andpatients without complications.Results: The study revealed that microalbumin levels are at a significantly higher range with high HbA1c levels in patients with complications(p<0.05). When compared to patients without complications.Conclusion: The study supports that strict glycemic control can prevent microalbuminuria and thereby prevent progress on to diabetic nephropathyin patients with Type 2 diabetes mellitus.Keywords: Microalbuminuria, Glycated hemoglobin, Diabetic complication

Palladium nanocatalysts encapsulated on porous silica @ magnetic carbon-coated cobalt nanoparticles for sustainable hydrogenations of nitroarenes, alkenes and alkynes

Palladium nanoparticles were impregnated on porous silica shell carbon-coated cobalt nanoparticles, resulting in a magnetically retrievable material that was evaluated in the catalytic hydrogenation of nitroarenes, alkenes and alkynes. The prepared material was characterized by HR-XRD, HR-TEM, elemental mapping EDX, ICP-OES and XPS analyses, revealing highly dispersed palladium nanoparticles within the porous platform that could account for the high activity observed. Mild reaction conditions, easy retrievability of the catalyst with the aid of an external magnet, recycling in four runs with a total leaching of 19 ppm (1.2 % of the initially employed Pd amount), and high stability makes this material attractive for sustainable and environmentally benign applications

Gendering international student migration: an Indian case-study

Despite the mainstreaming of gender perspectives into migration research, very few attempts have been made to gender international student migration. This paper poses three questions about Indian students who study abroad. Are there gender differences in their motivations? How do they negotiate their gendered everyday lives when abroad? Is the return to India shaped by gender relations? An online survey of Indian study-abroad students (n = 157), and in-depth interviews with Indian students in Toronto (n = 22), returned students in New Delhi (n = 21), and with parents of students abroad (n = 22) help to provide answers. Conceptually, the paper draws on a ‘gendered geographies of power’ framework and on student migration as an embodied process subject to ‘matrices of (un)intelligibility’. We find minimal gender-related differences in motivations to study abroad, except that male students are drawn from a wider social background. However, whilst abroad, both male and female Indian students face challenges in performing their gendered identities. The Indian patrifocal family puts greater pressure on males to return; females face greater challenges upon return

Evaluation of Power Quality Issues in grid Connected PV Systems

This paper deals with the evaluation of power quality issues in grid connected PV systems. This paper also presents  complete simulation, modeling and control of three phase grid connected solar PV module with Maximum Power Point Tracking. Perturb and Observe (P&O) method has been used for Maximum Power Point Tracking. In the proposed model DC bus voltage control , harmonic mitigation and power factor control are discussed as power quality issues. The simulation results are shown in the graphical waveforms and simulation is performed in MATLAB using SIMULINK environment and PSB toolboxes.

Histone degradation in response to DNA damage enhances chromatin dynamics and recombination rates

Nucleosomes are essential for proper chromatin organization and the maintenance of genome integrity. Histones are post-translationally modified and often evicted at sites of DNA breaks, facilitating the recruitment of repair factors. Whether such chromatin changes are localized or genome-wide is debated. Here we show that cellular levels of histones drop 20-40% in response to DNA damage. This histone loss occurs from chromatin, is proteasome-mediated and requires both the DNA damage checkpoint and the INO80 nucleosome remodeler. We confirmed reductions in histone levels by stable isotope labeling of amino acids in cell culture (SILAC)-based mass spectrometry, genome-wide nucleosome mapping and fluorescence microscopy. Chromatin decompaction and increased fiber flexibility accompanied histone degradation, both in response to DNA damage and after artificial reduction of histone levels. As a result, recombination rates and DNA-repair focus turnover were enhanced. Thus, we propose that a generalized reduction in nucleosome occupancy is an integral part of the DNA damage response in yeast that provides mechanisms for enhanced chromatin mobility and homology search.</p

NFATc2 Modulates Microglial Activation in the AβPP/PS1 Mouse Model of Alzheimer\u27s Disease

Alzheimer’s disease (AD) brains are characterized by fibrillar amyloid-β (Aβ) peptide containing plaques and associated reactive microglia. The proinflammatory phenotype of the microglia suggests that they may negatively affect disease course and contribute to behavioral decline. This hypothesis predicts that attenuating microglial activation may provide benefit against disease. Prior work from our laboratory and others has characterized a role for the transcription factor, nuclear factor of activated T cells (NFAT), in regulating microglial phenotype in response to different stimuli, including Aβ peptide. We observed that the NFATc2 isoform was the most highly expressed in murine microglia cultures, and inhibition or deletion of NFATc2 was sufficient to attenuate the ability of the microglia to secrete cytokines. In order to determine whether the NFATc2 isoform, in particular, was a valid immunomodulatory target in vivo, we crossed an NFATc2–/– line to a well-known AD mouse model, an AβPP/PS1 mouse line. As expected, the AβPP/PS1 x NFATc2–/– mice had attenuated cytokine levels compared to AβPP/PS1 mice as well as reduced microgliosis and astrogliosis with no effect on plaque load. Although some species differences in relative isoform expression may exist between murine and human microglia, it appears that microglial NFAT activity is a viable target for modulating the proinflammatory changes that occur during AD