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On the systematic status of the genus Oriocalotes Gunther, 1864 (Squamata: Agamidae: Draconinae) with the description of a new species from Mizoram state, Northeast India
No full textThe montane agamid lizard genus Oriocalotes is currently considered monotypic, represented by the species, O. paulus. The systematic status of this taxon has remained questionable since its initial descriptions in the mid-1800s. A detailed molecular and morphological study was carried out to assess the validity of this genus, and its systematic position within the Asian agamid subfamily, Draconinae. Freshly collected and historical museum specimens from the type locality of O. paulus were examined morphologically, along with additional samples collected from localities in Mizoram state, Northeast India. Utilising newly generated molecular sequences (two mitochondrial and three nuclear genes), combined with those previously published for representative genera from the subfamilies Draconinae and Agaminae, Maximum Likelihood and Bayesian phylogenetic trees were constructed. Phylogenetic results suggest that Oriocalotes is part of the widespread South and Southeast Asian radiation of Calotes. Comparative morphological studies (including external morphology, hemipenis and osteology) between Oriocalotes and related genera further support this systematic placement. Oriocalotes is herein regarded as a junior subjective synonym of Calotes. Calotes paulus comb. nov. is also assigned a lectotype and given a detailed redescription based on the lectotype, paralectotypes and additional topotypic material. Furthermore, the specimens collected from Mizoram populations are found to be morphologically and genetically distinct from Calotes paulus comb. nov., and are described herein as a new species, Calotes zolaiking sp. nov
Patterns of nitrogen-fixing tree abundance in forests across Asia and America
No full textAbstract
1. Symbiotic nitrogen (N)‐fixing trees can provide large quantities of new N to ecosystems, but only if they are sufficiently abundant. The overall abundance and
latitudinal abundance distributions of N‐fixing trees are well characterised in the Americas, but less well outside the Americas.
2. Here, we characterised the abundance of N‐fixing trees in a network of forest plots spanning five continents, ~5,000 tree species and ~4 million trees.The majority of the plots (86%)were in America o rAsia. In addition, we examined whether the observed pattern of abundance of N‐fixing trees was correlated with mean annual temperature and precipitation.
3.Outside the tropics, N‐fixing trees were consistently rare in the forest plots we examined. Within the tropics, N‐fixing trees were abundant in American but not Asian forest plots (~7% versus ~1% of basal area and stems). This disparity was not explained by mean annual temperature or precipitation. Our finding of low N‐fixing tree abundance in the Asian tropics casts some doubt on recent high estimates
of N fixation rates in this region, which do not account for disparities in N‐fixing tree abundance between the Asian and American tropics.
4. Synthesis. Inputs of nitrogen to forests depend on symbiotic nitrogen fixation, which is constrained by the abundance of N‐fixing trees. By analysing a large dataset of
~4 million trees, we found that N‐fixing trees were consistently rare in the Asian tropics as well as across higher latitudes in Asia, America and Europe. The rarity of
N‐fixing trees in the Asian tropics compared with the American tropics might stem from lower intrinsic N limitation in Asian tropical forests, although direct support for any mechanism is lacking. The paucity of N‐fixing trees throughout Asian forests suggests that N inputs to the Asian tropics might be lower than previously though
In vivo safety assessment of Lactobacillus fermentum strains, evaluation of their cholesterol-lowering ability and intestinal microbial modulation
No full textBACKGROUND Despite the growing importance of probiotics apparent health benefits, an impediment to the use of new probiotic cultures is their safety. Hence there is a need to strictly examine the biosafety as well as health benefits of probiotics in in vivo model systems. RESULTS In this study, two lactic acid bacterial (LAB) cultures Lactobacillus fermentum NCMR 2826 and FIX proven for their in vitro probiotic properties were investigated for their in vivo safety in Wistar rats. An acute toxicity study (14 days) with a high dose of biomass (10(16) colony-forming units (CFU) mL(-1)) followed by a subchronic test for 13 weeks with oral feeding of the probiotic cultures in three different doses (10(7), 10(8) and 10(10) CFU mL(-1)) on a daily basis revealed the safety of the L. fermentum cultures. The probiotic feeding had no toxic effects on survival, body weight and food consumption with any of the dosages used throughout the treatment period. No statistically significant changes in relative organ weights and serum biochemical and hematological indices were found between the control and the probiotic fed animals. In addition to the safety attributes, the L. fermentum culture fed rats showed reduced serum cholesterol levels, macrovesicular steatosis and hepatocyte ballooning compared with control animals. Further, quantification of intestinal microbiota using real-time polymerase chain reaction (PCR) analysis from animal feces indicated a significant increase and stability of Lactobacillus and Bifidobacterium counts but a decrease of Escherichia coli numbers. CONCLUSION This study of safety and beneficial features highlights the use of the two native L. fermentum isolates as potential probiotic food supplements
Effects of winter and summer-time irrigation over Gangetic Plain on the mean and intra-seasonal variability of Indian summer monsoon (vol 53, pg 3147, 2019)
No full textIn the original publication of the article, the significant hatching (cross marks on some grids) is not visible
A multiparametric organ toxicity predictor for drug discovery
No full textThe assessment of major organ toxicities through in silico predictive models plays a crucial role in drug discovery. Computational tools can predict chemical toxicities using the knowledge gained from experimental studies which drastically reduces the attrition rate of compounds during drug discovery and developmental stages. The purpose of in silico predictions for drug leads and anticipating toxicological endpoints of absorption, distribution, metabolism, excretion and toxicity, clinical adverse impacts and metabolism of pharmaceutically active substances has gained widespread acceptance in academia and pharmaceutical industries. With unrestricted accessibility to powerful biomarkers, researchers have an opportunity to contemplate the most accurate predictive scores to evaluate drug's adverse impact on various organs. A multiparametric model involving physico-chemical properties, quantitative structure-activity relationship predictions and docking score was found to be a more reliable predictor for estimating chemical toxicities with potential to reflect atomic-level insights. These in silico models provide informed decisions to carry out in vitro and in vivo studies and subsequently confirms the molecules clues deciphering the cytotoxicity, pharmacokinetics, and pharmacodynamics and organ toxicity properties of compounds. Even though the drugs withdrawn by USFDA at later phases of drug discovery which should have passed all the state-of-the-art experimental approaches and currently acceptable toxicity filters, there is a dire need to interconnect all these molecular key properties to enhance our knowledge and guide in the identification of leads to drug optimization phases. Current computational tools can predict ADMET and organ toxicities based on pharmacophore fingerprint, toxicophores and advanced machine-learning techniques
Understanding the dual mechanism of bioactive peptides targeting the enzymes involved in Renin Angiotensin System (RAS): An in-silico approach
No full textUnderstanding the dual inhibition mechanism of food derivative peptides targeting the enzymes (Renin and Angiotensin Converting enzyme) in the Renin Angiotensin System. Two peptides RALP and WYT were reported to possess antihypertensive activity targeting both renin and ACE, and we have used molecular docking and molecular dynamics simulation, in order to understand the underlying mechanism. The selected peptides (RALP and WYT) from the series of peptides reported were docked to renin and ACE and two binding modes were selected based on the binding energy, interaction pattern and clusters of docking simulation. The enzyme-peptide complexes for renin and ACE (Renin/RALP(1,2;) ACE/RALP(1,2); Renin/WYT1,2 and ACE/WYT1,2) were subjected to molecular dynamics simulation. Our results identified that the peptides inhibiting renin, tends to move out of the binding pockets (S1' S2') which is critical for potent binding and occupies the less important pockets (S4 and S3). This could possibly be the reason for its low potency. Whereas, the same peptides targeting ACE, tends to be intact in the pocket because of the metal ion coordination and there is an ample room to improve on its efficacy. Our results further pave way for the biochemist, medicinal chemist to design dual peptides targeting the RAS effectively. Communicated by Ramaswamy H. Sarm
Smoothness and norm attainment of bounded bilinear operators between Banach spaces
No full textWe study the smoothness and the norm attainment of bounded bilinear operators between Banach spaces, using the concepts of Birkhoff-James orthogonality and semi-inner-products. In the finite-dimensional case, we characterize Birkhoff-James orthogonality of bilinear operators in terms of the norm attainment set. This yields a nice characterization of smoothness of bilinear operators between Banach spaces, in the finite-dimensional case. Without any restriction on the dimension of the space, we obtain a complete characterization of the norm attainment set of a bounded bilinear operator using semi-inner-products, which is particularly useful when the concerned Banach spaces are smooth
BCG revaccination boosts adaptive polyfunctional Th1/Th17 and innate effectors in IGRA(+) and IGRA(-) Indian adults
No full textBACKGROUND. Bacille Calmette-Guerin (BCG) vaccine is protective against Tuberculosis (TB) in children, but its efficacy wanes with age. Consequently, determining if BCG revaccination augments anti-TB immunity in young adults in TB endemic regions is vital. METHODS. Two hundred healthy adults, BCG vaccinated at birth, were tested for their IFN-gamma release assay (IGRA) status. Of these, 28 IGRA(+) and 30 IGRA(-) were BCG revaccinated, and 24 IGRA(+) and 23 IGRA(-) subjects served as unvaccinated controls. T and innate cell responses to mycobacterial antigens were analyzed by 14-color flow cytometry over 34 weeks. RESULTS. IFN-gamma and/or IL-2 Ag85A- and BCG-specific CD4(+) and CD8(+) T cell responses were boosted by revacciantion at 4 and 34 weeks, respectively, and were > 2-fold higher in IGRA(+) compared with IGRA- vaccinees. Polyfunctional Ag85A, BCG, and mycobacterium tuberculosis (Mtb) latency Ag-specific (LTAg-specific) CD4(+) T cells expressing up to 8 cytokines were also significantly enhanced in both IGRA+ and IGRA- vaccinees relative to unvaccinated controls, most markedly in IGRA(+) vaccinees. A focused analysis of Th17 responses revealed expansion of Ag85A-, BCG-, and LTAg-specific total IL-17A(+),IL-17F(+),IL-22(+), and IL-10(+) CD4(+) T cell effectors in both IGRA(+) and IGRA- subjects. Also, innate IFN-gamma(+) NK/gamma delta/NKT cell responses were higher in both IGRA(+) and IGRA- vaccinees compared with controls. This is the first evidence to our knowledge that BCG revaccination significantly boosts antimycobacterial Th1/Th17 responses in IGRA(+) and IGRA- subjects. CONCLUSION. These data show that BCG revaccination is immunogenic in IGRA- and IGRA(+) subjects, implying that Mtb preinfection in IGRA(+) subjects does not impact immunogenicity. This has implications for public health and vaccine development strategies
Observation of second harmonic generation from multilayer Tin diselenide
No full textWe report spatially resolved second harmonic generation from a multilayer tin di-selenide flake using a nonlinear optical microscopy setup. The second order nonlinear signal from times weaker than that of quartz substrate. Tin di-selenide is expected to exhibit centrosymmetric lattice arrangement with vanishing second-order nonlinear optical effects. The observed second order nonlinear effects from multi-layer is ascribed to lattice distortions
Structural and electrical properties of lead-free Ba0.85Ca0.15Zr0.1Ti0.9O3 ceramic
No full textLead-free Ba0.85Ca0.15Zr0.1Ti0.9O3 (BCZT) ceramic has been prepared by solgel synthesis method. The effect of sintering temperature on the structure of BCZT ceramic was investigated. X-ray Diffraction studies show the suppression of secondary phase TiO2 with an increase in sintering temperature. The formation oftetragonal-orthorhombic morphotropic phase boundary is observed at the sintering temperature of 1350 °C. Polarization (P) versus electric field (E) measurementshows a remnant polarization of 1.32 μC/cm2 and coercive field of 4.33 kV/cm