Star formation in outer rings of S0 galaxies. I. NGC 6534 and MCG 11-22-015

Though S0 galaxies are usually thought to be `red and dead', they often demonstrate star formation organized in ring structures. We try to clarify the nature of this phenomenon and its difference from star formation in spiral galaxies. Two early-type galaxies with outer rings, NGC 6534 and MCG 11-22-015, are selected to be studied. The ionized gas is excited by young stars in the ring of NGC 6534 and partly by shocks -- in MCG 11-22-015. The oxygen abundances in the HII regions of the rings are close to solar. We estimate the star formation rates (SFR) in the two outer rings of the galaxies by using several SFR indicators derived from narrow-band photometry in the H-alpha emission line and archival GALEX ultraviolet images of the galaxies. The derived SFRs allow to qualitatively restore star formation histories (SFH) in the rings: in NGC 6534 the SFH is flat during the last 100-200 Myr, and in MCG 11-22-015 the star formation has started only a few Myr ago. We suggest that the rings in NGC 6534 and MCG 11-22-015 have different natures: the former is a resonant one supplied with gas perhaps through tidal effects, and the latter has been produced by a satellite accretion. Recent outer gas accretion is implied in both cases.Comment: 5 pages, 6 figures, accepted into the Astronomy and Astrophysic

TREX1 is expressed by microglia in normal human brain and increases in regions affected by ischemia

BACKGROUND: Mutations in the three-prime repair exonuclease 1 (TREX1) gene have been associated with neurological diseases, including Retinal Vasculopathy with Cerebral Leukoencephalopathy (RVCL). However, the endogenous expression of TREX1 in human brain has not been studied. METHODS: We produced a rabbit polyclonal antibody (pAb) to TREX1 to characterize TREX1 by Western blotting (WB) of cell lysates from normal controls and subjects carrying an RVCL frame-shift mutation. Dual staining was performed to determine cell types expressing TREX1 in human brain tissue. TREX1 distribution in human brain was further evaluated by immunohistochemical analyses of formalin-fixed, paraffin-embedded samples from normal controls and patients with RVCL and ischemic stroke. RESULTS: After validating the specificity of our anti-TREX1 rabbit pAb, WB analysis was utilized to detect the endogenous wild-type and frame-shift mutant of TREX1 in cell lysates. Dual staining in human brain tissues from patients with RVCL and normal controls localized TREX1 to a subset of microglia and macrophages. Quantification of immunohistochemical staining of the cerebral cortex revealed that TREX1 CONCLUSIONS: TREX1 is expressed by a subset of microglia in normal human brain, often in close proximity to the microvasculature, and increases in the setting of ischemic lesions. These findings suggest a role for TREX

Pattern of antimicrobial usage for prophylaxis of surgical site infection in a tertiary care hospital of Western Uttar Pradesh

Background: The practice of giving antibiotic prophylaxis has resulted in the reduction of surgical site infections (SSI), thus reducing cost, morbidity, and mortality. Common nosocomial infections in surgical patients include SSIs, urinary tract infections (UTIs), pneumonias and blood stream infections (BSIs). The present study was, therefore, designed to analyze the efficacy of antimicrobials used for prophylaxis during surgery in a tertiary care hospital in India.Methods: Total 100 patients were enrolled. Name, timing, route, dose of antimicrobials given were recorded. All the relevant data was taken from the patient’s medication charts and medical records. Chi-square test and t-test were applied.Results: The optimal time of giving antimicrobial prophylaxis in present study was 1 hour before the surgery. A total of 8 different antimicrobials were prescribed to 100 patients, out of which most commonly prescribed were cephalosporin i.e. 82%. Majority of SSI (57.12%) occurred when the duration of surgical antimicrobial prophylaxis (SAP) was for ≥2 hours (p value <0.05). Common organisms seen in SSI were E. coli, S. aureus, Pseudomonas and Kleibsella species. The hospital stay of patients with SSI was more as compared to patients without SSI in present study (p value <0.05).Conclusions: It has been observed that inappropriate selection and timing of giving SAP play an important role in developing SSI, which can be adequately controlled by adopting SAP guidelines, good infection control practices and risk factor analysis

Multidimensional Tests of Thermal Protection Materials in the Arcjet Test Facility

Many thermal protection system materials used for spacecraft heatshields have anisotropic thermal properties, causing them to display significantly different thermal characteristics in different directions, when subjected to a heating environment during flight or arcjet tests. This paper investigates the effects of sidewall heating coupled with anisotropic thermal properties of thermal protection materials in the arcjet environment. Phenolic Impregnated Carbon Ablator (PICA) and LI-2200 materials (the insulation material of Shuttle tiles) were used for this study. First, conduction-based thermal response simulations were carried out, using the Marc.Mentat finite element solver, to study the effects of sidewall heating on PICA arcjet coupons. The simulation showed that sidewall heating plays a significant role in thermal response of these models. Arcjet tests at the Aerodynamic Heating Facility (AHF) at NASA Ames Research Center were performed later on instrumented coupons to obtain temperature history at sidewall and various radial locations. The details of instrumentation and experimental technique are the prime focus of this paper. The results obtained from testing confirmed that sidewall heating plays a significant role in thermal response of these models. The test results were later used to verify the two-dimensional ablation, thermal response, and sizing program, TITAN. The test data and model predictions were found to be in excellent agreemen

an urgent priority

publishersversionpublishe

Perspectives of chalcopyrite-based CIGSe thin-film solar cell: a review

Solar photovoltaic (PV) is empowering, reliable, and ecofriendly technology for harvesting energy which can be assessed from the fact that PV panels with total electricity generation capacity of 505 GW have been installed by the end of 2018. Thin-film solar cells based on copper indium gallium selenide (CIGSe) are promising photovoltaic absorber material owing to an alternative to crystalline silicon (c-Si)-based solar cells because of the huge potential for low-cost solar electricity production with minimal usage of raw materials. The efficiency record of 23.4% was achieved recently in CIGSe solar cells, which was comparable to c-Si solar cells (27.6%). The manufacturing cost of $0.34/W is expected for 15% efficient CIGSe module. The present review article discusses the perspectives of CISe/CIGSe-based thin-film solar cells with the focus on absorber material. Different vacuum and non-vacuum techniques for fabricating these materials are discussed along with the operation of solar cells and their manufacturability. The working mechanism of CIGSe solar cells with the characteristic features of the open-circuit voltage and current density as well as the factors influencing the efficiency in different fabrication techniques are reviewed. Moreover, some strategies toward the improvement of solar cells performance contemplating modified deposition are reviewed. Furthermore, how these strategies can be executed in order to make it cost effective methods is also discussed in detail. Prevailing constrictions for the commercial maturity are deliberated, and future perspectives for improvement at lab as well as industrial scalabilities are outlined

New roles for the major human 3'-5' exonuclease TREX1 in human disease

Aicardi-Goutières syndrome (AGS), Systemic Lupus Erythematosus (SLE), Familial Chilblain Lupus (FCL) and Retinal Vasculopathy and Cerebral Leukodystrophy (RVCL) {a new term encompassing three independently described conditions with a common etiology—Cerebroretinal Vasculopathy (CRV), Hereditary Vascular Retinopathy (HVR) and Hereditary Endotheliopathy, Retinopathy and Nephropathy (HERNS)}—have previously been regarded as distinct entities. However, recent genetic analysis has demonstrated that each of these diseases maps to chromosome 3p21 and can be caused by mutations in TREX1, the major human 3'–5' exonuclease. In this review, we discuss the putative functions of TREX1 in relationship to the clinical, genetic and functional characteristics of each of these conditions

Cancer beliefs and screening behaviors: The impact of neighborhood and other social determinants of health

BackgroundBeliefs about cancer influence breast and colorectal cancer (CRC) screening behavior. Screening rates for these cancers differ in the contiguous neighborhoods of East Harlem (EH), Central Harlem (CH), and the Upper East Side (UES), which have distinct socio-demographic compositions. We assessed the belief-screening behavior relationship in these neighborhoods.MethodsThe 2019 Community Cancer Needs Survey included adults eligible for breast and/or colorectal cancer screening. Raking was used to generate neighborhood-specific distribution estimates. Categorical variables were compared using Chi-square tests. Stepwise logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI) for the association between cancer beliefs and screening.ResultsOur weighted sample included 147,726 respondents. Screening was 75% in CH, 81% in EH, and 90% in the UES for breast cancer, and 71%, 76%, and 92% for CRC, respectively. The fatalistic belief “There’s not much you can do to lower your chances of getting cancer” differed by neighborhood with screening more likely in CH respondents (breast OR =1.45 and colorectal OR =1.11), but less likely in EH (OR= 0.77 and 0.37, respectively). UES ORs were not generated due to too few unscreened respondents.ConclusionsCancer beliefs were inconsistently associated with breast and CRC screening across three NYC neighborhoods. This suggests that a given belief may either motivate or deter screening, depending upon context or interpretation. Once access is addressed, efforts seeking to enhance screening rates should consider implications of communities’ varying beliefs