The state of Jammu and Kashmir in North India experienced one of the worst floods in the past 60 years, during the first week of September 2014. In the present study, multi-temporal synthetic ...aperture radar (SAR) satellite images acquired from Indian Remote Sensing (IRS) satellite RISAT-1 and Canadian satellite Radarsat-2 during the peak flood period (08th-23rd September 2014) are used for extraction of flood disaster footprints, mapping spatial and temporal dynamics of flood inundation and assessing the disaster impact. With the aid of pre- and post-flood satellite images, coupled with hydro-meteorological data, the unprecedented flood situation is analyzed. It is estimated that about 557 km
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of the Kashmir Valley's geographical area was inundated. Bandipora, Pulwama, Srinagar, Baramulla and Budgam were the worst flood affected districts, having more than 50 km
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of their area affected by flood waters. Of the total inundated area, about 80% of the area under agricultural activity was submerged, followed by built-up areas constituting about 12% of geographical area. About 22 lakh people in 287 villages were affected by floods. The flood waters persisted in the northern and central part of the valley for more than two weeks.
Rising global temperatures due to climate change are affecting crop performance in several regions of the world. High temperatures affect plants at various organizational levels, primarily ...accelerating phenology to limit biomass production and shortening reproductive phase to curtail flower and fruit numbers, thus resulting in severe yield losses. Besides, heat stress also disrupts normal growth, development, cellular metabolism, and gene expression, which alters shoot and root structures, branching patterns, leaf surface and orientation, and anatomical, structural, and functional aspects of leaves and flowers. The reproductive growth stage is crucial in plants’ life cycle, and susceptible to high temperatures, as reproductive processes are negatively impacted thus reducing crop yield. Genetic variation exists among genotypes of various crops to resist impacts of heat stress. Several screening studies have successfully phenotyped large populations of various crops to distinguish heat-tolerant and heat-sensitive genotypes using various traits, related to shoots (including leaves), flowers, fruits (pods, spikes, spikelets), and seeds (or grains), which have led to direct release of heat-tolerant cultivars in some cases (such as chickpea). In the present review, we discuss examples of contrasting genotypes for heat tolerance in different crops, involving many traits related to thermotolerance in leaves (membrane thermostability, photosynthetic efficiency, chlorophyll content, chlorophyll fluorescence, stomatal activity), flowers (pollen viability, pollen germination, fertilization, ovule viability), roots (architecture), biomolecules (antioxidants, osmolytes, phytohormones, heat-shock proteins, other stress proteins), and “omics” (phenomics, transcriptomics, genomics) approaches. The traits linked to heat tolerance can be introgressed into high yielding but heat-sensitive genotypes of crops to enhance their thermotolerance. Involving these traits will be useful for screening contrasting genotypes and would pave the way for characterizing the underlying molecular mechanisms, which could be valuable for engineering plants with enhanced thermotolerance. Wherever possible, we discussed breeding and biotechnological approaches for using these traits to develop heat-tolerant genotypes of various food crops.
The present study examined the equivalent black carbon (eBC) mass concentrations measured over 10.5 years (September 2005–March 2016) using a 7-wavelength Aethalometer (AE-31) at Mukteshwar, a ...high-altitude and regional background site in the foothills of Indian central Himalayas. The total spectral absorption coefficient (babs) was divided into three categories: black carbon (BC) and brown carbon (BrC); fossil fuels (FF) and wood/biomass burning (WB/BB); and primary and secondary sources. At the wavelength of 370 nm, a significant BrC contribution (25 %) to the total babs is identified, characterized by a pronounced seasonal variation with winter (December–January-February) maxima (31 %) and post-monsoon (October and November) minima (20 %); whereas, at 660 nm, the contribution of BrC is dramatically less (9 %). Climatologically, the estimated BCFF at 880 nm ranges from 0.25 ± 0.19 μg m−3 in July to 1.17 ± 0.80 μg m−3 in May with the annual average of 0.67 ± 0.63 μg m−3, accounting for 79 % of the BC mass. The maximum BCFF/BC fraction reaches its peak value during the monsoon (July and August, 85 %), indicating the dominance of local traffic emissions due to tourism activities. Further, the highest BCWB concentration observed during pre-monsoon (March–May) suggests the influence of local forest fires along with long-range transported aerosols from the low-altitude plains. The increased contribution of BrC (26 % at 370 nm) and WB absorption (61 % at 370 nm) to the total absorption at the shorter wavelengths suggests that wood burning is one of the major sources of BrC emissions. Secondary BrC absorption accounts for 24 % 91 % of the total absorption BrC absorption at 370 nm, implying the dominance of secondary sources in BrC formation. A trend analysis for the measured BC concentration shows a statistically significant increasing trend with a slope of 0.02 μgm−3/year with a total increase of about 22 % over the study period. A back trajectory-based receptor model, potential source contribution function (PSCF), was used to identify the potential regional source region of BC. The main source regions of BC are the northwest states of India in the IGP region and the northeast Pakistan region.
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•Significant (25 %) contribution of Brown Carbon to the total absorption at the UV range.•Highest concentrations associated with wood burning during pre-monsoon and winter.•Significant fossil fuel contribution to total black carbon is observed due to tourism activities.•Black carbon showed a statistically significant increasing trend of ~2 %/year.
Effects of temperature and strain rate on the tensile properties of Cu-Cr-Zr-Ti alloy in annealed condition were investigated by varying the initial strain rates from 10−4s−1 to 10−1s−1 at RT, 300°C, ...450°C, 600°C and 700°C. The yield strength (YS) and ultimate tensile strength (UTS) of the alloy increased with an increase in strain rate at RT and 300°C, whereas at 450°C, the material exhibited the highest YS and UTS at the lowest strain rate of 10−4s−1. At 600°C, the YS and UTS of the alloy increased with an increase in strain rate and showed the highest YS compared to all the temperatures tested. The alloy showed serrated yielding at 300°C and at an initial strain rate of 10−4s−1 whereas at 450°C, serrated yielding was observed at 10−3s−1 and 10−4s−1 strain rates. Microstructural observations showed the presence of creep cavities at 450°C and strain rate of 10−4s−1. The creep cavities were present at higher strain rates as the test temperature is increased. Fractography indicates that the fracture is predominantly dimple fracture at RT and 300°C and intergranular cracks were observed at 600°C and 700°C.
The Multi-Angle Absorption Photometer (MAAP) is a widely-used instrument for aerosol black carbon (BC) measurements. In this paper, we show correction methods for an artifact found to affect the ...instrument accuracy in environments characterized by high black carbon concentrations. The artifact occurs after a filter spot change – as BC mass is accumulated on a fresh filter spot, the attenuation of the light (raw signal) is weaker than anticipated. This causes a sudden decrease, followed by a gradual increase in measured BC concentration. The artifact is present in the data when the BC concentration exceeds ~3 μg m−3 at the typical MAAP flow rate of 16.7 L min−1 or 1 m3 h−1. The artifact is caused by erroneous dark counts in the photodetector measuring the transmitted light, in combination with an instrument internal averaging procedure of the photodetector raw signals. It was found that, in addition to the erroneous temporal response of the data, concentrations higher than 9 μg m−3 (at the flow rate of 16.7 L min−1) are underestimated by the MAAP. The underestimation increases with increasing BC accumulation rate. At a flow rate of 16.7 L min−1 and concentration of about 24 μg m−3 (BC accumulation rate ~0.4 μg min−1), the underestimation is about 30%. There are two ways of overcoming the MAAP artifact. One method is by logging the raw signal of the 165° photomultiplier measuring the reflected light from the filter spot. As this signal is not affected by the artifact, it can be converted to approximately correct absorption and BC values. However, as the typical print formats of the MAAP do not give the reflected signal as an output, a semi-empirical correction method was developed based on laboratory experiments to correct for the results in the post-processing phase. The correction function was applied to three MAAP datasets from Gual Pahari (India), Beijing (China), and Welgegund (South Africa). In Beijing, the results could also be compared against a photoacoustic spectrometer (PAS). The correction improved the quality of all three MAAP datasets substantially, even though the individual instruments operated at different flow rates and in different environments.
A culture system that closely recapitulates marrow physiology is essential to study the niche-mediated regulation of hematopoietic stem cell fate at a molecular level. We investigated the key ...features that play a crucial role in the formation of a functional niche in vitro.
Hydrogel-based cultures of human placenta-derived mesenchymal stromal cells were established to recapitulate the fibrous three-dimensional architecture of the marrow. Plastic-adherent mesenchymal stromal cells were used as controls. Human bone marrow-derived CD34(+) cells were co-cultured with them. The output hematopoietic cells were characterized by various stem cell-specific phenotypic and functional parameters.
The hydrogel-cultures harbored a large pool of primitive hematopoietic stem cells with superior phenotypic and functional attributes. Most importantly, like the situation in vivo, a significant fraction of these cells remained quiescent in the face of a robust multi-lineage hematopoiesis. The retention of a high percentage of primitive stem cells by the hydrogel-cultures was attributed to the presence of CXCR4-SDF1α axis and integrin beta1-mediated adhesive interactions. The hydrogel-grown mesenchymal stromal cells expressed high levels of several molecules that are known to support the maintenance of hematopoietic stem cells. Yet another physiologically relevant property exhibited by the hydrogel cultures was the formation of hypoxia-gradient. Destruction of hypoxia-gradient by incubating these cultures in a hypoxia chamber destroyed their specialized niche properties.
Our data show that hydrogel-based cultures of mesenchymal stromal cells form a functional in vitro niche by mimicking key features of marrow physiology.
Cultivars with efficient root systems play a major role in enhancing resource use efficiency, particularly water absorption, and thus in drought tolerance. In this study, a diverse wheat association ...panel of 136 wheat accessions including mini core subset was genotyped using Axiom 35k Breeders' Array to identify genomic regions associated with seedling stage root architecture and shoot traits using multi-locus genome-wide association studies (ML-GWAS). The association panel revealed a wide variation of 1.5- to 50-fold and were grouped into six clusters based on 15 traits. Six different ML-GWAS models revealed 456 significant quantitative trait nucleotides (QTNs) for various traits with phenotypic variance in the range of 0.12-38.60%. Of these, 87 QTNs were repeatedly detected by two or more models and were considered reliable genomic regions for the respective traits. Among these QTNs, eleven were associated with average diameter and nine each for second order lateral root number (SOLRN), root volume (RV) and root length density (RLD). A total of eleven genomic regions were pleiotropic and each controlled two or three traits. Some important candidate genes such as Formin homology 1, Ubiquitin-like domain superfamily and ATP-dependent 6-phosphofructokinase were identified from the associated genomic regions. The genomic regions/genes identified in this study could potentially be targeted for improving root traits and drought tolerance in wheat.
In general, the prediction models are increasingly being used for reasoning and decision making in various applications. With the advancements in IT based devices such as Tablet-PC, touch-screen ...based smart phones, digital-pen/stylus based devices, and digitizers, the demand of real-time based applications is also increasing. The present study describes the Language Model (LM) based forecasting the occurrence of next possible Gurmukhi character/word in a word/sentence, which depends on the immediately preceding character(s)/word(s), written in the real-time environment. The online handwritten captured character/word information is first segmented into its individual strokes, which are recognized using Support Vector Machine (SVM) classifier. Once a character/word is recognized, this will be useful to assist the writers in order to provide the suggestions for next possible character/word. The
n
-gram language models (bigram and trigram) have been implemented at character- and word-level for this purpose. In this study, the corpus, “Punjabi Monolingual Text Corpus-AnglaMT” (available at
https://tdil-dc.in
), containing approximately 83,000 sentences has been used for training the model. Experimental results show that the proposed online handwritten character/word forecasting framework significantly outperforms and produce consistent forecasts for the most likely character/word on the basis of given handwritten character/word information and saving computational costs. This model can also be used for many other non-Indic and Indic scripting languages.
Objectives: Acute-on-chronic liver failure (ACLF), which develops in patients with underlying alcoholic liver disease (ALD), is characterized by acute deterioration of liver function and organ ...failures are secondary to that. The clear understanding of metabolic pathways perturbed in ALD-ACLF patients can greatly decrease the mortality and morbidity of patients through predicting outcome, guiding treatment, and monitoring response to treatment. The purpose of this study was to investigate the metabolic disturbances associated with ACLF using nuclear magnetic resonance (NMR)-based serum metabolomics approach and further to assess if the serum metabolic alterations are affected by the severity of hepatic impairment. Materials and Methods: The serum-metabolic profiles of 40 ALD-ACLF patients were compared to those of 49 age and sex-matched normal-control (NC) subjects making composite use of both multivariate and univariate statistical tests. Results: Compared to NC, the sera of ACLF patients were characterized by significantly decreased serum levels of several amino acids (except methionine and tyrosine), lipid, and membrane metabolites suggesting a kind of nutritional deficiency and disturbed metabolic homeostasis in ACLF. Twelve serum metabolic entities (including BCAA, histidine, alanine, threonine, and glutamine) were found with AUROC (i.e., area under ROC curve) value >0.9 suggesting their potential in clinical diagnosis and surveillance. Conclusion: Overall, the study revealed important metabolic changes underlying the pathophysiology of ACLF and those related to disease progression would add value to standard clinical scores of severity to predict outcome and may serve as surrogate endpoints for evaluating treatment response.
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