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A deep convolutional neural network has been developed to denoise atomic-resolution transmission electron microscope image datasets of nanoparticles acquired using direct electron counting detectors, for applications where the image signal is severely limited by shot noise. The network was applied to a model system of CeO2-supported Pt nanoparticles. We leverage multislice image simulations to generate a large and flexible dataset for training the network. The proposed network outperforms state-of-the-art denoising methods on both simulated and experimental test data. Factors contributing to the performance are identified, including (a) the geometry of the images used during training and (b) the size of the network's receptive field. Through a gradient-based analysis, we investigate the mechanisms learned by the network to denoise experimental images. This shows that the network exploits both extended and local information in the noisy measurements, for example, by adapting its filtering approach when it encounters atomic-level defects at the nanoparticle surface. Extensive analysis has been done to characterize the network's ability to correctly predict the exact atomic structure at the nanoparticle surface. Finally, we develop an approach based on the log-likelihood ratio test that provides a quantitative measure of the agreement between the noisy observation and the atomic-level structure in the network-denoised image.
A diverse set of 107 rice genotypes was evaluated for yield, shattering and dormancy traits. Analysis of variance revealed sizable variation while skewness and kurtosis values indicated near-normal distribution for most of the traits, thus quantitative nature controlled by many genes. A highly significant deviation from a normal distribution for dormancy and shattering % indicated their qualitative nature of inheritance. Four promising genotypes ‘IRGC1723’ (early with 65 days to flowering), ‘IRGC 11108’ and ‘RNR 15459’ (high grain number – 358 and low average shattering – <5%), ‘RNR 11718’ (high single plant yield – 56.73 g, low average shattering – <5% and dormancy period – 21 days) are identified. A significant positive correlation between shattering and dormancy confirms inter-relationship among domestication-related characteristics. The principal component analysis revealed the contribution of four PCs to maximum variability and hierarchical clustering grouped the genotypes into 18 divergent clusters. Five cultivars (Karimnagar Samba, Sheetal, PR 121, Pranahitha and Jagitial Samba) with a combination of low shattering ability (3.35–5.7%) and considerable dormancy period (13–20 days) falling in the same cluster can be used as donors for the improvement of rice genotypes with low shattering ability and incorporating a considerable period of dormancy so as to avoid pre-harvest sprouting due to delayed harvesting. Further, they can be crossed with ‘Pratyumna’ having less than 1 week dormancy period, a genotype of the cluster XVII with which they have a maximum genetic divergence of 51.4 and may serve as parents in the development of mapping populations for the identification of QTLs/genes for shattering and dormancy traits.
In chilli, farmer preferences for fruiting habit traits, namely fruit orientation (pendant erect) and fruits node−1 (solitary cluster), vary from region to region. For increased acceptability by farmers/consumers, cultivars should be bred with preferred fruiting habit traits in high green fruit yielding background. An investigation was carried out to study the influence of fruiting habit traits on green fruit yield and its component traits during the 2016 and 2017 rainy seasons. The F2, backcross populations and near-isogenic lines (NILs) derived from crosses involving parents differing for single or both the fruiting habit traits were grouped into fruiting habit classes (single and cluster fruiting; and clustered erect, clustered pendant, single erect and single pendant). Significance of differences in fruit yield and its component traits between/among different fruiting habit trait classes were examined using ‘t’/‘F’ tests. The significance of ‘t’/‘F’ tests was regarded as pieces of evidence for considerable effects of fruiting habit traits on fruit yield and its component traits. While results-based on F2 and backcross generations indicated a lack of effects, those based on NILs indicated significant effects of fruiting habit traits on fruit yield and its component traits. The plants bearing pendant fruits (irrespective of whether they are clustered or single) produced a large number of heavier and longer fruits than those bearing erect fruits. The results are discussed about the strategies to develop high yielding cultivars with farmer preferred fruiting habit traits.
In this study, AA5083-reinforced multiwalled carbon nanotubes (MWCNT) nanocomposites were selected as the alternate material for a redundant articulated robot (RAR) design by varying the composition of MWCNT wt%. By assigning AA5083-reinforced MWCNT as a custom material to the parts of RAR developed by Solid Works and exported to MATLAB/SimMechanics platform to convert the model into multi-body system blocks. The dynamic parameter torque was observed utilising simulation capability in a SimMechanics second-generation environment. The simulation results inferred that AA5083 reinforced with increased wt% of MWCNT has better properties suitable for RAR design.
Early childhood factors can have persisting effects on development and cognition in children. We propose to explore the trends of Fe deficiency and Pb toxicity in early childhood and their association with child development at 2 years of age and cognition at 5 years.
Longitudinal birth cohort study.
Urban slum, Vellore, India.
Children enrolled at birth were followed up regularly in the first 2 years with developmental and cognitive assessments at 2 and 5 years of age, respectively.
The birth cohort enrolled 251 children with 228 children followed up at 2 years and 212 at 5 years of age. Fe deficiency (ID) was highest at 15 months of age and improved subsequently at 24 months. Blood Pb levels (BLL) remained high at all age groups with an increasing trend with age; 97 % at 36 months having high BLL. Persistent high mean BLL at 15 and 24 months had negative association with both cognition and expressive language raw scores of 24 months, while high mean BLL at 15, 24 and 36 months had no significant association with any of the domains of cognition at 5 years of age. Early childhood cumulative body Fe status at 7, 15 and 24 months did not show any association with child development at 2 years, but was associated with verbal, performance and processing speed components of cognition at 5 years.
Optimising body Fe status and limiting Pb exposure in early childhood can augment child development and school entry cognition.
The present study assessed the prevalence of vitamin D deficiency in an urban south Indian population in individuals with different grades of glucose tolerance. A total of 1500 individuals (900 normal glucose tolerance (NGT), 300 prediabetes and 300 with type 2 diabetes mellitus (T2DM)) who were not on vitamin D supplementation were randomly selected from the Chennai Urban Rural Epidemiological Study follow-up study. Anthropometric, clinical examination and biochemical investigations (25-hydroxyvitamin D (25(OH)D), insulin, glycated Hb (HbA1c) and serum lipids) were measured. Vitamin D deficiency was defined as serum 25(OH)D < 20·0 ng/ml, insufficiency as 20–29·9 ng/ml and sufficiency as ≥30 ng/ml. Of the 1500 individuals studied, 45 % were males and the mean age was 46 (sd 12) years. Vitamin D levels lowered with increasing degrees of glucose tolerance (NGT: 21 (sd 11); prediabetes: 19 (sd 10); T2DM: 18 (sd 11) ng/ml, P < 0·001). The overall prevalence of vitamin D deficiency was 55 % and was significantly higher among individuals with T2DM (63 %) followed by prediabetes (58 %) and NGT (51 %) (Pfor trend < 0·001). Women had 1·6 times the risk of vitamin D deficiency compared with men (unadjusted OR 1·6 (95 % CI 1·3, 2·0) and adjusted OR 1·6 (95 % CI 1·2, 1·9)). However, there was no increasing trend observed with increasing age. The prevalence of abdominal obesity (66 v. 49 %), generalised obesity (80 v. 64 %), the metabolic syndrome (45 v. 37 %) and insulin resistance (38 v. 27 %) was significantly higher in those with vitamin D deficiency compared with those without. This study shows that vitamin D deficiency is highly prevalent in this urban south Indian population and was higher among individuals with T2DM and prediabetes compared with those with NGT.
A new species of Eriocaulon, E. vamanae, is described from the southern Western Ghats of Kerala, India. It resembles Eriocaulon nepalense var. luzulifolium (Mart.) Praj. & J.Parn. but differs in the shape of its involucral bracts and receptacle, the fusion of the sepals in male flowers, the shape and indumentum of the sepals in female flowers, the size and indumentum of the petals in female flowers, and the seed coat appendages. Eriocaulon vamanae is so far known only from the type locality, Meesapulimala in Idukki District, Kerala, and is assessed as ‘Critically Endangered’ according to the IUCN’s Red List Categories and Criteria.
Choice of the most appropriate breeding method hinges on mode of action of genes controlling expression of target traits. Pungency (capsaicin) and colour (oleoresin) are most important fruit quality traits in chilli. Genetics of fruit quality traits was unravelled using a combination of first and second degree statistics. An additive-dominance model was inadequate to explain the inheritance of fruit yield and quality traits. Magnitude of additive genetic effects [a] and their variances [σ2A] were higher than those of dominance genetic effects [d] and dominance genetic variances [σ2D] suggesting predominance of additive effect genes in the inheritance of both oleoresin and capsaicin contents. These results are discussed in relation to appropriate selection strategy to be followed for genetic improvement of chilli for oleoresin and capsaicin contents.
India has the second largest number of people with type 2 diabetes (T2D) globally. Epidemiological evidence indicates that consumption of white rice is positively associated with T2D risk, while intake of brown rice is inversely associated. Thus, we explored the effect of substituting brown rice for white rice on T2D risk factors among adults in urban South India. A total of 166 overweight (BMI ≥ 23 kg/m2) adults aged 25–65 years were enrolled in a randomised cross-over trial in Chennai, India. Interventions were a parboiled brown rice or white rice regimen providing two ad libitum meals/d, 6 d/week for 3 months with a 2-week washout period. Primary outcomes were blood glucose, insulin, glycosylated Hb (HbA1c), insulin resistance (homeostasis model assessment of insulin resistance) and lipids. High-sensitivity C-reactive protein (hs-CRP) was a secondary outcome. We did not observe significant between-group differences for primary outcomes among all participants. However, a significant reduction in HbA1c was observed in the brown rice group among participants with the metabolic syndrome (−0·18 (se 0·08) %) relative to those without the metabolic syndrome (0·05 (se 0·05) %) (P-for-heterogeneity = 0·02). Improvements in HbA1c, total and LDL-cholesterol were observed in the brown rice group among participants with a BMI ≥ 25 kg/m2 compared with those with a BMI < 25 kg/m2 (P-for-heterogeneity < 0·05). We observed a smaller increase in hs-CRP in the brown (0·03 (sd 2·12) mg/l) compared with white rice group (0·63 (sd 2·35) mg/l) (P = 0·04). In conclusion, substituting brown rice for white rice showed a potential benefit on HbA1c among participants with the metabolic syndrome and an elevated BMI. A small benefit on inflammation was also observed.
Traditional approaches to materials synthesis have largely relied on uniform, equilibrated phases leading to static “condensed-matter” structures (e.g., monolithic single crystals). Departures from these modes of materials design are pervasive in biology. From the folding of proteins to the reorganization of self-regulating cytoskeletal networks, biological materials reflect a major shift in emphasis from equilibrium thermodynamic regimes to out-of-equilibrium regimes. Here, equilibrium structures, determined by global free-energy minima, are replaced by highly structured dynamical states that are out of equilibrium, calling into question the utility of global thermodynamic energy minimization as a first-principles approach. Thus, the creation of new materials capable of performing life-like functions such as complex and cooperative processes, self-replication, and self-repair, will ultimately rely upon incorporating biological principles of spatiotemporal modes of self-assembly. Elucidating fundamental principles for the design of such out-of-equilibrium dynamic self-assembling materials systems is the focus of this issue of MRS Bulletin.
Improving understanding of the pathogen-specific seasonality of enteric infections is critical to informing policy on the timing of preventive measures and to forecast trends in the burden of diarrhoeal disease. Data obtained from active surveillance of cohorts can capture the underlying infection status as transmission occurs in the community. The purpose of this study was to characterise rotavirus seasonality in eight different locations while adjusting for age, calendar time and within-subject clustering of episodes by applying an adapted Serfling model approach to data from a multi-site cohort study. In the Bangladesh and Peru sites, within-subject clustering was high, with more than half of infants who experienced one rotavirus infection going on to experience a second and more than 20% experiencing a third. In the five sites that are in countries that had not introduced the rotavirus vaccine, the model predicted a primary peak in prevalence during the dry season and, in three of these, a secondary peak during the rainy season. The patterns predicted by this approach are broadly congruent with several emerging hypotheses about rotavirus transmission and are consistent for both symptomatic and asymptomatic rotavirus episodes. These findings have practical implications for programme design, but caution should be exercised in deriving inferences about the underlying pathways driving these trends, particularly when extending the approach to other pathogens.
It was proposed in Ref. 1 that cryogenic temperatures can be achieved by the adiabatic isentropic expansion of a gas. The scheme is shown in Fig. 1. High pressure gas contained in A expands by means of valve 1 and cools. Valve 2 is then opened along with nozzle valve to push cold test gas through the working section.
In the ideal case the process is isentropic. To achieve reservoir conditions of T=120K and P = 4·4 bars, the initial pressure needed would be 110 bars. However, because of heat transfer from the walls of the tube, the process is not ideal and the actual initial pressure needed is higher. The main parameters which affect the heat transfer are the internal surface area of the tube, the rate of expansion governed by the size of valve 1 and the initial pressure of the gas.
The Evolutionary Map of the Universe (EMU) is a proposed radio continuum survey
of the Southern Hemisphere up to declination + 30°, with the Australian
Square Kilometre Array Pathfinder (ASKAP). EMU will use an automated source
identification and measurement approach that is demonstrably optimal, to
maximise the reliability and robustness of the resulting radio source
catalogues. As a step toward this goal we conducted a “Data
Challenge” to test a variety of source finders on simulated images. The
aim is to quantify the accuracy and limitations of existing automated source
finding and measurement approaches. The Challenge initiators also tested the
current ASKAPsoft source-finding tool to establish how it could benefit from
incorporating successful features of the other tools. As expected, most finders
show completeness around 100% at ≈ 10σ dropping to about 10% by
≈ 5σ. Reliability is typically close to 100% at ≈
10σ, with performance to lower sensitivities varying between finders. All
finders show the expected trade-off, where a high completeness at low
signal-to-noise gives a corresponding reduction in reliability, and vice versa.
We conclude with a series of recommendations for improving the performance of
the ASKAPsoft source-finding tool.
Diarrhoeal diseases are major causes of morbidity and mortality in developing countries. This longitudinal study aimed to identify controllable environmental drivers of intestinal infections amidst a highly contaminated drinking water supply in urban slums and villages of Vellore, Tamil Nadu in southern India. Three hundred households with children (<5 years) residing in two semi-urban slums and three villages were visited weekly for 12–18 months to monitor gastrointestinal morbidity. Households were surveyed at baseline to obtain information on environmental and behavioural factors relevant to diarrhoea. There were 258 diarrhoeal episodes during the follow-up period, resulting in an overall incidence rate of 0·12 episodes/person-year. Incidence and longitudinal prevalence rates of diarrhoea were twofold higher in the slums compared to rural communities (P < 0·0002). Regardless of study site, diarrhoeal incidence was highest in infants (<1 year) at 1·07 episodes/person-year, and decreased gradually with increasing age. Increasing diarrhoeal rates were associated with presence of children (<5 years), domesticated animals and low socioeconomic status. In rural communities, open-field defecation was associated with diarrhoea in young children. This study demonstrates the contribution of site-specific environmental and behavioural factors in influencing endemic rates of urban and rural diarrhoea in a region with highly contaminated drinking water.
Physical inactivity and low birth weight (LBW) may lead to an increased risk for developing type 2 diabetes. The extent to which LBW individuals may benefit from physical exercise training when compared with those with normal birth weight (NBW) controls is uncertain. We assessed the impact of an outdoor exercise intervention on body composition, insulin secretion and action in young men born with LBW and NBW in rural India. A total of 61 LBW and 56 NBW healthy young men were recruited into the study. The individuals were instructed to perform outdoor bicycle exercise training for 45 min every day. Fasting blood samples, intravenous glucose tolerance tests and bioimpedance body composition assessment were carried out. Physical activity was measured using combined accelerometry and heart rate monitoring during the first and the last week of the intervention. Following the exercise intervention, the LBW group displayed an increase in physical fitness [55.0 ml (O2)/kg min (52.0−58.0)−57.5 ml (O2)/kg min (54.4−60.5)] level and total fat-free mass [10.9% (8.0−13.4)−11.4% (8.0−14.6)], as well as a corresponding decline in the ratio of total fat mass/fat-free mass. In contrast, an increase in total fat percentage as well as total fat mass was observed in the NBW group. After intervention, fasting plasma insulin levels, homoeostasis model assessments (HOMA) of insulin resistance (HOMA-IR) and insulin secretion (HOMA-IS), improved to the same extent in both the groups. In summary, young men born with LBW in rural India benefit metabolically from exercise training to an extent comparable with NBW controls.
Gallium nitride (n-type) films of thickness 300nm were grown on c-plane sapphire substrates using plasma assisted molecular beam epitaxy (PA-MBE). High resolution X-ray diffraction and photoluminescence measurements were used to confirm the crystalline and optical qualities of the grown films. Metal-semiconductor Schottky diodes were fabricated using Pt as the Schottky metal and Al as the Ohmic metal contact. Metal-insulator-semiconductor Schottky diodes were also fabricated using HfO2 (10nm) as the insulator material. Diode parameters like barrier height and ideality factor were extracted from I-V measurements. Introduction of HfO2 as the insulator layer leads to better rectifying behavior (forward to reverse current ratio improves from 5.1 to 8.9) with a reduction in reverse leakage current (by 7.4 times), increase in barrier height (from 0.62eV to 0.74eV) and a reduction in ideality factor (from 6 to 4.1) of the Schottky diode.
Kimura's disease is a rare, localised, chronic inflammatory disease. This benign disease involves subcutaneous tissues, the major salivary gland, and lymph nodes primarily in the head and neck area.
Clinical details and stained slides of all cases reported as Kimura's disease over a 10-year period were reviewed.
There were eight cases of Kimura's disease. The mean age of patients was 22.8 years. One case showed associated nephrotic syndrome and two cases were associated with peripheral blood eosinophilia. All cases showed the typical histopathological features of Kimura's disease.
Kimura's disease was first reported in China in 1937. The cause of Kimura's disease is unknown and many theories have been proposed. The eight cases reported here illustrate some of the variations in the mode of presentation and in the histological features of Kimura's disease. Kimura's disease should be considered in the differential diagnosis of patients who present with head and neck swellings and lymphadenopathy, and investigated accordingly.