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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.
Nature’s optical nanomaterials are poised to form the platform for future optical devices with unprecedented functionality. The brilliant colors of many animals arise from the physical interaction of light with nanostructured, multifunctional materials. While their length scale is typically in the 100-nm range, the morphology of these structures can vary strongly. These biological nanostructures are obtained in a controlled manner, using biomaterials under ambient conditions. The formation processes nature employs use elements of both equilibrium self-assembly and far-from-equilibrium and growth processes. This renders not only the colors themselves, but also the formation processes technologically and ecologically highly relevant. Yet, for many biological nanostructured materials, little is known about the formation mechanisms—partially due to a lack of in vivo imaging methods. Here, we present the toolbox of natural multifunctional nanostructures and the current knowledge about the understanding of their far-from-equilibrium assembly processes.
Far-from-equilibrium systems are ubiquitous in nature. They are also rich in terms of diversity and complexity. Therefore, it is an intellectual challenge to be able to understand the physics of far-from-equilibrium phenomena. In this article, we revisit a standard tabletop experiment, the Rayleigh–Bénard convection, to explore some fundamental questions and present a new perspective from a first-principles point of view. We address how nonequilibrium fluctuations differ from equilibrium fluctuations, how emergence of order out of equilibrium breaks symmetries in the system, and how free energy of a system gets locally bifurcated to operate a Carnot-like engine to maintain order. The exploration and investigation of these nontrivial questions are the focus of this article.
Materials can be endowed with unique properties by the integration of molecular motors. Molecular motors can have a biological origin or can be chemically synthesized and produce work from chemical energy or light. Their ability to access large internal or external reservoirs of energy enables a wide range of nonequilibrium behaviors, including the production of force, changes in shape, internal reorganization, and dynamic changes in mechanical properties—muscle tissue is one illustration of the possibilities. Current research efforts advance our experimental capabilities to create such “active matter” by using either biomolecular or synthetic motors, and also advance our theoretical understanding of these materials systems. Here, we introduce this exciting research field and highlight a few of the recent advances as well as open questions.
This article addresses why biomaterials are a growing part of materials science. We consider two areas at two different scales. At the nanometer scale, enzymes are heterogeneous nanoparticles of extraordinary deformability; this property allows us to view biomolecules informed by concepts of materials science and nonlinear physics. A degree of universality in the mechanical behavior of the molecules appears in the ubiquitous softening transitions; some results obtained dynamically by nanorheology, and others obtained in equilibrium experiments through the method of the DNA springs are summarized. These soft molecules represent an opportunity for studies of dissipation at the atomic scale. At the mesoscopic scale, composite functional materials with biological components hold promise for applications such as low power, chemically driven, biodegradable devices. A concrete example, and a program for the future, is the artificial axon. It is a synthetic structure that supports action potentials based on the same physical mechanism as the voltage spikes in nerve cells. A network of such axons, which is yet to come, would constitute an artificial brain. Beyond device applications, the focus here is on the basic science, namely, a constructivist approach to cybernetics, algorithmic mathematics, and the brain.