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We report the synthesis and optical properties of pure ZnS and Ag doped ZnS nanostructures. ZnS(Ag) was synthesized by using the hydrothermal technique and later annealed at different temperatures under vacuum conditions. It was observed that the photoluminescence (PL) emission from the ZnS(Ag) nanostructures can be easily tuned from the blue (445 nm) to green (530 nm) region of visible light by varying the annealing temperature. This tunability has been attributed to the introduction of excess sulfur vacancy states, which is evident from the PL excitation spectra. This observed change in the PL emission wavelength can be highly beneficial in the imaging screens where ZnS is regularly used and can be easily interfaced with the silicon photodiodes showing maximum sensitivity at 550 nm.
The coronal field typically reorganizes itself to attain a force-free field configuration. We have evaluated the power law index of the energy distribution f(E) = f0E−α by using a model of relaxation incorporating different profile functions of winding number distribution f(w) based on braided topologies. We study the radio signatures that occur in the solar corona using the radio data obtained from the Gauribidanur Radio Observatory (IIA) and extract the power law index by using the Statistic-sensitive nonlinear iterative peak clipping (SNIP) algorithm. We see that the power law index obtained from the model is in good agreement with the calculated value from the radio data observation.
We construct two classes of the magnetohydrostatic equilibria of the axisymmetric flux tubes with twisted magnetic fields in the stratified solar atmosphere that span from the photosphere to the transition region. We built the models by incorporating specific forms of the gas pressure and poloidal current in the Grad-Shafranov equation. This model gives both closed and open field structure of the flux tube. The other open field model we construct is based on the self-similar formulation, where we have incorporated specific forms of the gas pressure, poloidal current and two different shape functions. We study the homology of the parameter space that is consistent with the solar atmosphere and find that the estimation of the magnetic structure inside the flux tubes is consistent with the observation and simulation results of the magnetic bright points.
Policy-makers and practitioners have a need to assess community resilience in disasters. Prior efforts conflated resilience with community functioning, combined resistance and recovery (the components of resilience), and relied on a static model for what is inherently a dynamic process. We sought to develop linked conceptual and computational models of community functioning and resilience after a disaster.
We developed a system dynamics computational model that predicts community functioning after a disaster. The computational model outputted the time course of community functioning before, during, and after a disaster, which was used to calculate resistance, recovery, and resilience for all US counties.
The conceptual model explicitly separated resilience from community functioning and identified all key components for each, which were translated into a system dynamics computational model with connections and feedbacks. The components were represented by publicly available measures at the county level. Baseline community functioning, resistance, recovery, and resilience evidenced a range of values and geographic clustering, consistent with hypotheses based on the disaster literature.
The work is transparent, motivates ongoing refinements, and identifies areas for improved measurements. After validation, such a model can be used to identify effective investments to enhance community resilience. (Disaster Med Public Health Preparedness. 2018;12:127–137)
The Proterozoic Sushina Hill Complex is the only agpaitic complex, reported from India and is characterized by a eudialyte-rinkite-bearing nepheline syenite. The complex is considered a ‘metamorphosed agpaitic complex'. This study describes the mineral assemblages formed during successive stages of evolution from magmatic to hydrothermal stages and low-temperature subsolidus re-equilibration assemblage. The primary-late magmatic assemblage is characterized by albite, orthoclase, unaltered nepheline, zoned diopside-hedenbergite, rinkite, late magmatic eudialyte and magnesio-arfvedsonite formed at ∼700°C with maximum aSiO2 of 0.60. In contrast, a deuteric assemblage (400-348°C) is represented by aegirine-jadeite-rich clinopyroxene, post-magmatic eudialyte, sodalite, analcime and the decomposition assemblages formed after eudialyte with decreasing aSiO2 (0.52-0.48). A further low-temperature subsolidus assemblage (≤250°C) represented by late-forming natrolite could be either related to regressive stages of metamorphism or a continuum of the subsolidus processes. Considering the P/T range of the greenschist - lower-amphibolite facies of metamorphism it is evident that the incorporation of a jadeite component within pyroxene is related to a subsolidus process between ∼400°C and 348°C in a silica deficient environment. We emphasize that the deuteric fluid itself acted as an agent of metamorphism and the decomposition assemblage formed after eudialyte is retained even after metamorphism due to the convergence of subsolidus and metamorphic domains. The formation of jadeite-rich aegirine is not considered to result from metamorphism. Overall it is near-impossible to discern any bona fide metamorphic textures or mineral assemblages in these syenites which appear to preserve a relict mineralogy regardless of their occurrence in country rocks which have experienced greenschist - amphibolite facies metamorphism. The Sushina complex is very similar in this respect to the Norra Kärr complex (Sweden).
The effect of maternal nutrition level during the periconception period on the muscle development of fetus and maternal–fetal plasma hormone concentrations in sheep were examined. Estrus was synchronized in 55 Karayaka ewes and were either fed ad libitum (well-fed, WF, n=23) or 0.5×maintenance (under-fed, UF, n=32) 6 days before and 7 days after mating. Non-pregnant ewes (WF, n=13; UF, n=24) and ewes carrying twins (WF, n=1) and female (WF, n=1; UF, n=3) fetuses were removed from the experiment. The singleton male fetuses from well-fed (n=8) and under-fed (n=5) ewes were collected on day 90 of gestation and placental characteristics, fetal BWs and dimensions, fetal organs and muscles weights were recorded. Maternal (on day 7 after mating) and fetal (on day 90 of pregnancy) blood samples were collected to analyze plasma hormone concentrations. Placental characteristics, BW and dimensions, organs and muscles weights of fetuses were not affected by maternal feed intake during the periconception period. Maternal nutrition level did not affect fiber numbers and the muscle cross-sectional area of the fetal longissimus dorsi (LD), semitendinosus (ST) muscles, but the cross-sectional area of the secondary fibers in the fetal LD and ST muscles from the UF ewes were higher than those from the WF ewes (P<0.05). Also, the ratio of secondary to primary fibers in the ST muscle were tended to be lower in the fetuses from the UF ewes (P=0.07). Maternal nutrition level during the periconception period did not cause any significant changes in fetal plasma insulin and maternal and fetal plasma IGF-I, cortisol, progesterone, free T3 and T4 concentrations. However, maternal cortisol concentrations were lower while insulin concentrations were higher in the WF ewes than those in the UF ewes (P<0.05). These results indicate that the reduced maternal feed intake during the periconception period may alter muscle fiber diameter without affecting fiber types, fetal weights and organ developments and plasma hormone concentrations in the fetus.
Outcrop-scale structures and magnetic fabric anisotropy of the Bomdila Gneiss (BG) that intruded the Lesser Himalayan Crystallines (LHC) of the Arunachal Lesser Himalaya are studied to understand the BG deformation history and tectonic evolution. Detailed analysis of structures reveals that the LHC have undergone three phases of deformation, D1, D2 and D3. The S2 foliation developed during the second phase of deformation (D2) is the most penetrative planar fabric in the studied rock, which shows a general ENE–WSW strike with moderate NW dip. Mesoscopic evidence of a later phase of deformation (D3) in the BG is lacking. Evidence of D3 deformation in the form of F3 folds is only observed in the adjacent metasedimentary rocks of the LHC. The magnetic foliations recorded from anisotropy of magnetic susceptibility (AMS) analysis of the BG are mostly striking NW–SE with a moderate dip towards the NE or SW, and magnetic lineation is mostly sub-horizontal and dominantly plunging towards the SE. Our study shows that the magnetic fabric of the BG does not correspond to any visible outcrop-scale mesoscale foliation. However, the magnetic foliation of the BG is parallel to the axial plane of the F3 folds of the adjacent metasedimentary rocks of the LHC. Integration of AMS and outcrop-scale structural analysis helps us envisage the superposed deformation history of the BG. Our study emphasizes the importance of AMS to detect late-stage or feeble deformation events that leave no visible outcrop-scale imprint and are difficult to discern through conventional geological means.
To report the International Nosocomial Infection Control Consortium surveillance data from 40 hospitals (20 cities) in India 2004–2013.
Surveillance using US National Healthcare Safety Network’s criteria and definitions, and International Nosocomial Infection Control Consortium methodology.
We collected data from 236,700 ICU patients for 970,713 bed-days
Pooled device-associated healthcare-associated infection rates for adult and pediatric ICUs were 5.1 central line–associated bloodstream infections (CLABSIs)/1,000 central line–days, 9.4 cases of ventilator-associated pneumonia (VAPs)/1,000 mechanical ventilator–days, and 2.1 catheter-associated urinary tract infections/1,000 urinary catheter–days
In neonatal ICUs (NICUs) pooled rates were 36.2 CLABSIs/1,000 central line–days and 1.9 VAPs/1,000 mechanical ventilator–days
Extra length of stay in adult and pediatric ICUs was 9.5 for CLABSI, 9.1 for VAP, and 10.0 for catheter-associated urinary tract infections. Extra length of stay in NICUs was 14.7 for CLABSI and 38.7 for VAP
Crude extra mortality was 16.3% for CLABSI, 22.7% for VAP, and 6.6% for catheter-associated urinary tract infections in adult and pediatric ICUs, and 1.2% for CLABSI and 8.3% for VAP in NICUs
Pooled device use ratios were 0.21 for mechanical ventilator, 0.39 for central line, and 0.53 for urinary catheter in adult and pediatric ICUs; and 0.07 for mechanical ventilator and 0.06 for central line in NICUs.
Despite a lower device use ratio in our ICUs, our device-associated healthcare-associated infection rates are higher than National Healthcare Safety Network, but lower than International Nosocomial Infection Control Consortium Report.
Infect. Control Hosp. Epidemiol. 2016;37(2):172–181
Sesame (Sesamum indicum L.) is one of the oldest and most nutritional oilseed crops, of which domestication history has been poorly understood. This study suggested that sesame has undergone domestication bottleneck during its use for a long time. In this investigation, the molecular analysis included 4.4 Mbp of the genomic DNA of sesame comprising stearoyl acyl desaturase (sad), fatty acid desaturase 2 (fad2) and omega 3 fatty acid desaturase (o3fad) genes in 99 accessions of four populations of sesame germplasm namely: wild species, landraces, improved cultivars and introgressed lines. Results indicated that the improved cultivars and landraces lost 46.6 and 36.7% of nucleotide diversity, respectively, which indicate that the genetic diversity of the crop had been eroded due to selection after domestication. However, there was no significant reduction in genetic diversity of improved cultivars compared with landraces, indicating that unique improved cultivars generated through crosses were of less frequency in this population. Moreover, introgressed lines retained only 17.77% (π) and 4.57% (θ) of landrace diversity. To evaluate the impact of selection across fatty acid biosynthetic pathway, individual nucleotide diversity at three major genes involved in the pathway was surveyed. The analysis between wild and improved cultivars supported positive selection in fad2 and o3fad loci. Though locus-to-locus sequence variation was observed, positive results with two most important loci supported selection after domestication. Reduced diversity in these critical quality governing genes in improved cultivars suggested that future sesame cultivation would benefit from the incorporation of alleles from sesame's wild relatives.
We describe two cases of anomalous origin of the left lower-lobe pulmonary artery from the right pulmonary artery. The primary diagnosis was mitral atresia, hypoplastic left ventricle, aortic arch hypoplasia in the first child, and tetralogy of Fallot in the second. In both cases, the pulmonary trunk gave rise to a left pulmonary artery in the normal position. In addition, a second branch of the left pulmonary artery arose from the right pulmonary artery, and passed posterior and inferior to the left main or upper-lobe bronchus to supply the left lower lobe. In this review, we compare our findings with previously reported examples of this extremely rare cardiac malformation, and discuss possible embryological explanations for the lesion.
Objectives: Insulin-like growth factor-1 may serve some regulatory function in the immune system. Rheumatic mitral stenosis is related to autoimmune heart valve damage after streptococcal infection. The aim of this study was to assess the level of insulin-like growth factor-1 and its correlation with the Wilkins score in patients with rheumatic mitral stenosis. Methods: A total of 65 patients with rheumatic mitral stenosis and 62 age- and sex-matched control subjects were enrolled in this study. All subjects underwent transthoracic echocardiography. The mitral valve area and Wilkins score were evaluated for all patients. Biochemical parameters and serum insulin-like growth factor-1 levels were measured. Results: Demographic data were similar in the rheumatic mitral stenosis and control groups. The mean mitral valve area was 1.6±0.4 cm2 in the rheumatic mitral stenosis group. The level of insulin-like growth factor-1 was significantly higher in the rheumatic mitral stenosis group than in the control group (104 (55.6–267) versus 79.1 (23.0–244.0) ng/ml; p=0.039). There was a significant moderate positive correlation between insulin-like growth factor-1 and thickening of leaflets score of Wilkins (r=0.541, p<0.001). Conclusions: The present study demonstrated that serum insulin-like growth factor-1 levels were significantly higher in the rheumatic mitral stenosis group compared with control subjects and that insulin-like growth factor-1 level was also correlated with the Wilkins score. It can be suggested that there may be a link between insulin-like growth factor-1 level and immune pathogenesis of rheumatic mitral stenosis.
For diagnostic purposes, the nine symptoms that compose the DSM-5 criteria for major depressive disorder (MDD) are assumed to be interchangeable indicators of one underlying disorder, implying that they should all have similar risk factors. The present study investigates this hypothesis, using a population cohort that shifts from low to elevated depression levels.
We assessed the nine DSM-5 MDD criterion symptoms (using the Patient Health Questionnaire; PHQ-9) and seven depression risk factors (personal and family MDD history, sex, childhood stress, neuroticism, work hours, and stressful life events) in a longitudinal study of medical interns prior to and throughout internship (n = 1289). We tested whether risk factors varied across symptoms, and whether a latent disease model could account for heterogeneity between symptoms.
All MDD symptoms increased significantly during residency training. Four risk factors predicted increases in unique subsets of PHQ-9 symptoms over time (depression history, childhood stress, sex, and stressful life events), whereas neuroticism and work hours predicted increases in all symptoms, albeit to varying magnitudes. MDD family history did not predict increases in any symptom. The strong heterogeneity of associations persisted after controlling for a latent depression factor.
The influence of risk factors varies substantially across DSM depression criterion symptoms. As symptoms are etiologically heterogeneous, considering individual symptoms in addition to depression diagnosis might offer important insights obfuscated by symptom sum scores.
We report on the effect of the International Nosocomial Infection Control Consortium's (INICC) multidimensional approach for the reduction of ventilator-associated pneumonia (VAP) in adult patients hospitalized in 21 intensive-care units (ICUs), from 14 hospitals in 10 Indian cities. A quasi-experimental study was conducted, which was divided into baseline and intervention periods. During baseline, prospective surveillance of VAP was performed applying the Centers for Disease Control and Prevention/National Healthcare Safety Network definitions and INICC methods. During intervention, our approach in each ICU included a bundle of interventions, education, outcome and process surveillance, and feedback of VAP rates and performance. Crude stratified rates were calculated, and by using random-effects Poisson regression to allow for clustering by ICU, the incidence rate ratio for each time period compared with the 3-month baseline was determined. The VAP rate was 17·43/1000 mechanical ventilator days during baseline, and 10·81 for intervention, showing a 38% VAP rate reduction (relative risk 0·62, 95% confidence interval 0·5–0·78, P = 0·0001).
Bidirectional reflectance of a surface is defined as the ratio of the scattered radiation at the detector to the incident irradiance as a function of geometry. Accurate knowledge of the bidirectional reflection function for layers composed of discrete, randomly positioned scattering particles is essential for many remote sensing, engineering, and biophysical applications, as well as for different areas of astrophysics. Computations of bidirectional reflection functions for plane parallel particulate layers are usually reduced to solving the radiative transfer equation by the existing techniques. In this work we present our laboratory data on bidirectional reflectance versus phase angle for two sample sizes of alumina, 0.3 and 1 μm, for the He–Ne laser at wavelengths of 632.8 nm (red) and 543.5 nm (green). The nature of the phase curves of the asteroids depends on the parameters like particle size, composition, porosity, roughness, etc. In the present study we analyze data which are being generated using a single scattering phase function, that is, Mie theory of treating particles as a compact sphere. The well-known Hapke formula, along with different particle phase functions such as Mie and Henyey–Greenstein, will be used to model the laboratory data obtained at the asteroid laboratory of Assam University.
Silicon is an important material not only for semiconductor applications, but also for the development of novel bioinspired and biomimicking materials and structures or drug delivery systems in the context of nanomedicine. For these applications, a thorough understanding of the fracture behavior of the material is critical. In this paper we address this issue by investigating a fundamental issue of the mechanical properties of silicon, its behavior under extreme mechanical loading. Earlier experimental work has shown that at low temperatures, silicon is a brittle material that fractures catastrophically like glass once the applied load exceeds a threshold value. At elevated temperatures, however, the behavior of silicon is ductile. This brittle-to-ductile transition (BDT) has been observed in many experimental studies of single crystals of silicon. However, the mechanisms that lead to this change in behavior remain questionable, and the atomic-scale phenomena are unknown. Here we report for the first time the direct atomistic simulation of the nucleation of dislocations from a crack tip in silicon only due to an increase of the temperature, using large-scale atomistic simulation with the first principles based ReaxFF force field. By raising the temperature in a computational experiment with otherwise identical boundary conditions, we show that the material response changes from brittle cracking to emission of a dislocation at the crack tip, representing evidence for a potential mechanisms of dislocation mediated ductility in silicon.
Over a 2-year period, 25 families comprising of 181 individuals of all ages were longitudinally observed for the excretion of Campylobacter species. Faecal samples were taken from all persons with diarrhoea. Specimens were also taken from apparently healthy individuals and from domestic animals living within the confines of the study families at monthly intervals.
The overall diarrhoea attack rate was 19 episodes per 100 person-years with peak incidence in the 1- to 4-year-old age group (76/100 person-years). Eight (11·5%) of the total episodes were campylobacter-associated and the overall rate of campylobacter positive diarrhoeal episodes were 2·2 per 100 person-years. Of the 1002 stool samples from healthy individuals 32 (3·2/100 samples) were positive for campylobacter. The organism was most frequently isolated from children under 1 year of age both during diarrhoeal episodes (11·5 per 100 person-years) and non-diarrhoeal (11·1 per 100 samples). Multiple infections in a family were rare. In 19·4% of the occasions one or more animals were campylobacter positive. However, only in 7·7% of these occasions was a human infection recorded within 1 month after the animal was found to be positive.
The study showed that the epidemiology of campylobacteriosis in this community was distinct compared to that observed in developed countries.
Nuclear DNA syntheses have been measured microspectrophotometrically in course of meiotic nuclear development in Neurospora crassa. The purpose of the study has been to establish the timing of these DNA syntheses in relation to meiosis and in the formation of its final products in an ideal genetic material, where the products of the meiotic division can be recovered and identified. Spectrophotometric analysis has indicated that the last premeiotic DNA replication is completed before caryogamy; a postmeiotic DNA replication takes place at the tetrad of the nuclei level; and finally a second postmeiotic DNA replication occurs in the ascospores to result in eight binucleated ascospores. The timing of postmeiotic replication is compatible with the models explaining gene conversion through the postulated mechanisms involving heteroduplex formation.