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In the quest of achieving sustainable crop productivity, improved soil health, and increased carbon (C) sequestration in the soil, conservation agriculture (CA) is increasingly being promoted and adopted in the Indian subcontinent. However, because some researchers from different regions of the world have reported reduced crop yield under CA relative to agriculture based on conventional tillage (CT), a meta-analysis has been conducted based on published research from India to evaluate the effects of CA on the yield of crops, accumulation of soil organic C as an index of soil health, and C sequestration in the soil in different regions and soil textural groups in the country. The meta-analysis is based on 544 paired observations under CA and CT from 35 publications from India was carried out using Meta Win 2.1 software. The results showed an overall significant (p < 0.05) reduction of 1.15% crop yield under CA compared to CT. Yearwise data showed a reduction of yields under CA from 2009 to 2016, but an increase from 2017 to 2020. Yield reduction was observed in the eastern, north-eastern, and southern regions of India but in western, northern, and north-western regions of the country, an increase was observed under CA rather than CT. Sandy loam and clayey soils exhibited higher crop yield under CA than under CT. Compared to CT, soil organic C content and soil C sequestration under CA increased by 8.9% and 7.3%, respectively. Also, in all the regions and soil textural groups both soil organic C accumulation and soil C sequestration were higher under CA than under CT. Factors such as rainfall, soil depth, available nitrogen (N), and total N significantly influenced the extent of yield increase/decrease and soil organic C accumulation under CA. Overall, results of the meta-analysis suggest that the promotion of CA in India will have to be location-specific taking into consideration the crops, soil attributes, and climatic conditions.
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Agricultura , Secuestro de Carbono , Conservación de los Recursos Naturales , Productos Agrícolas , Suelo , India , Suelo/química , Agricultura/métodos , Carbono/análisisRESUMEN
The microbe-mediated conversion of nitrate (NO3-) to ammonium (NH4+) in the nitrogen cycle has strong implications for soil health and crop productivity. The role of prokaryotes, eukaryotes and their phylogeny, physiology, and genetic regulations are essential for understanding the ecological significance of this empirical process. Several prokaryotes (bacteria and archaea), and a few eukaryotes (fungi and algae) are reported as NO3- reducers under certain conditions. This process involves enzymatic reactions which has been catalysed by nitrate reductases, nitrite reductases, and NH4+-assimilating enzymes. Earlier reports emphasised that single-cell prokaryotic or eukaryotic organisms are responsible for this process, which portrayed a prominent gap. Therefore, this study revisits the similarities and uniqueness of mechanism behind NO3- -reduction to NH4+ in both prokaryotes and eukaryotes. Moreover, phylogenetic, physiological, and genetic regulation also shed light on the evolutionary connections between two systems which could help us to better explain the NO3--reduction mechanisms over time. Reports also revealed that certain transcription factors like NtrC/NtrB and Nit2 have shown a major role in coordinating the expression of NO3- assimilation genes in response to NO3- availability. Overall, this review provides a comprehensive information about the complex fermentative and respiratory dissimilatory nitrate reduction to ammonium (DNRA) processes. Uncovering the complexity of this process across various organisms may further give insight into sustainable nitrogen management practices and might contribute to addressing global environmental challenges.
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Compuestos de Amonio , Archaea , Bacterias , Nitratos , Oxidación-Reducción , Filogenia , Nitratos/metabolismo , Compuestos de Amonio/metabolismo , Bacterias/genética , Bacterias/metabolismo , Bacterias/clasificación , Archaea/genética , Archaea/metabolismo , Archaea/clasificación , Eucariontes/genética , Eucariontes/metabolismo , Células Procariotas/metabolismo , Hongos/genética , Hongos/metabolismo , Hongos/clasificación , Ciclo del Nitrógeno/genética , Nitrito Reductasas/genética , Nitrito Reductasas/metabolismoRESUMEN
BACKGROUND: Chickpea is prone to many abiotic stresses such as heat, drought, salinity, etc. which cause severe loss in yield. Tolerance towards these stresses is quantitative in nature and many studies have been done to map the loci influencing these traits in different populations using different markers. This study is an attempt to meta-analyse those reported loci projected over a high-density consensus map to provide a more accurate information on the regions influencing heat, drought, cold and salinity tolerance in chickpea. RESULTS: A meta-analysis of QTL reported to be responsible for tolerance to drought, heat, cold and salinity stress tolerance in chickpeas was done. A total of 1512 QTL responsible for the concerned abiotic stress tolerance were collected from literature, of which 1189 were projected on a chickpea consensus genetic map. The QTL meta-analysis predicted 59 MQTL spread over all 8 chromosomes, responsible for these 4 kinds of abiotic stress tolerance in chickpea. The physical locations of 23 MQTL were validated by various marker-trait associations and genome-wide association studies. Out of these reported MQTL, CaMQAST1.1, CaMQAST4.1, CaMQAST4.4, CaMQAST7.8, and CaMQAST8.2 were suggested to be useful for different breeding approaches as they were responsible for high per cent variance explained (PVE), had small intervals and encompassed a large number of originally reported QTL. Many putative candidate genes that might be responsible for directly or indirectly conferring abiotic stress tolerance were identified in the region covered by 4 major MQTL- CaMQAST1.1, CaMQAST4.4, CaMQAST7.7, and CaMQAST6.4, such as heat shock proteins, auxin and gibberellin response factors, etc. CONCLUSION: The results of this study should be useful for the breeders and researchers to develop new chickpea varieties which are tolerant to drought, heat, cold, and salinity stresses.
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Cicer , Sitios de Carácter Cuantitativo , Estrés Fisiológico , Cicer/genética , Estrés Fisiológico/genética , Mapeo Cromosómico , Sequías , Estudio de Asociación del Genoma CompletoRESUMEN
Crop residue management has become more challenging with intensive agricultural operations. Zero tillage and crop residue returns, along with the enhancement of in-situ residue decomposition through microbial intervention, are essential measures for preserving and enhancing soil quality. To address this problem in view of stubble burning, field experiments were conducted in rice-rice (variety Swarna) cropping systems under lowland conditions, wherein the following different residue management practices were adopted viz., conventional cultivation (CC), residue incorporation (RI @ 6 t paddy straw ha-1), residue retention (RR @6 t paddy straw ha-1), and zero tillage (ZT). In this experiment, two microbial products i.e. solid microbial consortium (SMC) at 2.0 kg ha-1) and capsule (10 numbers ha-1), were evaluated in both Rabi (dry) and Kharif (wet) seasons under different residue management practices. The results on soil microbial properties showed that application of either SMC or capsule based formulation could significantly improve the soil organic carbon (SOC) content in ZT (9.51 g/kg), followed by RI (9.36 g/kg), and RR (9.34 g/kg) as compared to CC (7.61 g/kg). There were significant differences in the soil functional properties (AcP, AkP, FDA, and DHA) with microbial interventions across all residue management practices. SOC was significantly positive correlated with cellulase (R2 = 0.64, p < 0.001), ß-glucosidase (R2 = 0.61, p < 0.001), and laccase (R2 = 0.66, p < 0.001) activity; however, the regression coefficients varied significantly with microbial intervention. Moreover, the availability of N, P, and K in soil was significantly (p < 0.05) improved under microbial treatments with either RR or RI practices. Among the different methods of residues management practices, RI with microbial intervention registered a consistent yield improvement (8.4-17.8%) compared to conventional practices with microbial intervention. The present findings prove that the application of decomposing microbial consortia for in-situ rice residue management under field conditions significantly enhances soil quality and crop yield compared to conventional practices.
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Agricultura , Oryza , Microbiología del Suelo , Suelo , Oryza/crecimiento & desarrollo , India , Suelo/química , Agricultura/métodos , Productos AgrícolasRESUMEN
Dynamic interactions within the tumor micro-environment drive patient response to immune checkpoint inhibitors. Existing preclinical models lack true representation of this complexity. Using a Head and Neck cancer patient derived TruTumor histoculture platform, the response spectrum of 70 patients to anti-PD1 treatment is investigated in this study. With a subset of 55 patient samples, multiple assays to characterize T-cell reinvigoration and tumor cytotoxicity are performed. Based on levels of these two response parameters, patients are stratified into five sub-cohorts, with the best responder and non-responder sub-cohorts falling at extreme ends of the spectrum. The responder sub-cohort exhibits high T-cell reinvigoration, high tumor cytotoxicity with T-cells homing into the tumor upon treatment whereas immune suppression and tumor progression pathways are pre-dominant in the non-responders. Some moderate responders benefit from combination of anti-CTLA4 with anti-PD1, which is evident from better cytotoxic T-cell: T-regulatory cell ratio and enhancement of tumor cytotoxicity. Baseline and on-treatment gene expression signatures from this study stratify responders and non-responders in unrelated clinical datasets.
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Neoplasias de Cabeza y Cuello , Humanos , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Microambiente TumoralRESUMEN
Rice-based integrated farming system improves the productivity and profitability by recycling resources efficiently. In the sub-humid tropics, rice production without sufficient nutrient replenishment often leads to soil health and fertility degradation. There has been very limited research on soil health and fertility after adopting a multi-enterprising rice-based integrated farming system (IFS), notably in the rice-fish-livestock and agroforestry system, when compared to a conventional farming system (CS). Therefore, the present study analyzed the dynamics of soil properties, soil bacterial community structure and their possible interaction mechanisms, as well as their effect on regulating soil quality and production in IFS, IFSw (water stagnant area of IFS) and CS. The results indicated that soil nutrient dynamics, bacterial diversity indices (Shannon index, Simpson index, Chao 1, ACE and Fisher index) and system productivity were higher in IFSw and IFS compared to CS. Moreover, relative operational taxonomic units of dominant bacterial genera (Chloroflexi, Acidobacteria, Verrucomicrobia, Planctomycetes, Cyanobacteria, Crenarchaeota and Gemmatimonadetes) were also higher in IFSw and IFS compared to CS. Mean soil quality index (SQI) was highest in IFSw (0.780 ± 0.201) followed by IFS (0.770 ± 0.080) and CS (0.595 ± 0.244). Moreover, rice equivalent yields (REY) and rice yields were well correlated with the higher levels of soil biological indices (SQIBiol) in IFS. Overall, our results revealed that rice-based IFS improved the soil health and fertility and ensuing crop productivity through positive interaction with soil bacterial communities and nutrient stoichiometry leading to agroecosystem sustainability.
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Oryza , Suelo , Suelo/química , Clima Tropical , Agricultura/métodos , Bacterias , Microbiología del SueloRESUMEN
Here, we report a comparison study on the synthesis and characterization of perovskite SrSnO3 (SSO) and Sr2SnO4 (S2SO). Rietveld refinement studies were performed on both prepared samples and suggest that they crystallized in cubic (SSO) and tetragonal (S2SO) structures. Fourier-transform infrared (FTIR) and Raman spectroscopy studies supported the XRD observations. Improved dielectric parameters were observed for S2SO over SSO due to differences in dislocation density, larger crystallite size, and denser microstructure. The electrical conduction and relaxation processes followed the Arrhenius type in both samples through the migration of oxygen vacancies via the Sn-site and the transfer of electrons between the Sn sites in two different temperature regions. These processes in the samples occurred via correlated barrier hopping (CBH) in SSO and the non-overlapping of small-polaron tunnelling (NSPT) in S2SO. The conduction and relaxation processes had similar sources of charge carriers but differed in the concentration and mobility of charge carriers. The presented materials can be utilized for dielectric capacitors, sensors, and mixed ionic and electronic conductor-based electrodes in IT-SOFC applications.
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The grain-filling stage in Triticum aestivum (wheat) is highly vulnerable to increasing temperature as terminal heat stress diminishes grain quality and yield. To examine the mechanism of terminal heat tolerance, we performed the biochemical and gene expression analyses using two heat-tolerant (WH730 and WH1218) and two heat-sensitive (WH711 and WH157) wheat genotypes. We observed a significant increase in total soluble sugar (25%-47%), proline (7%-15%), and glycine betaine (GB) (22%-34%) contents in flag leaf, whereas a decrease in grain-filling duration, 1000-kernel weight (8%-25%), and grain yield per plant (11%-23%) was observed under the late-sown compared to the timely sown. The maximum content of osmolytes, including total soluble sugar, proline, and GB, was observed in heat-tolerant genotypes compared to heat-sensitive genotypes. The expression of 10 heat-responsive genes associated with heat shock proteins (sHsp-1, Hsp17, and HsfA4), flavonoid biosynthesis (F3'-1 and PAL), ß-glucan synthesis (CslF6 and CslH), and xyloglucan metabolism (XTH1, XTH2, and XTH5) was studied in flag leaf exposed to different heat treatments (34, 36, 38, and 40°C) at 15 days after anthesis by quantitative real-time polymerase chain reaction. A significant increase in the relative fold expression of these genes with increasing temperature indicated their involvement in providing heat-stress tolerance. The high differential expression of most of the genes in heat-tolerant genotype "WH730" followed by "WH1218" indicates the high adaptability of these genotypes to heat stress compared to heat-sensitive wheat genotypes. Based on the previous results, "WH730" performed better in terms of maximum osmolyte accumulation, grain yield, and gene expression under heat stress.
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Pan , Triticum , Triticum/genética , Respuesta al Choque Térmico/genética , Grano Comestible/genética , Prolina/genética , Expresión Génica , AzúcaresRESUMEN
Temperatures below or above optimal growth conditions are among the major stressors affecting productivity, end-use quality, and distribution of key staple crops including rice (Oryza sativa), wheat (Triticum aestivum), and maize (Zea mays L.). Among temperature stresses, cold stress induces cellular changes that cause oxidative stress and slowdown metabolism, limit growth, and ultimately reduce crop productivity. Perception of cold stress by plant cells leads to the activation of cold-responsive transcription factors and downstream genes, which ultimately impart cold tolerance. The response triggered in crops to cold stress includes gene expression/suppression, the accumulation of sugars upon chilling, and signaling molecules, among others. Much of the information on the effects of cold stress on perception, signal transduction, gene expression, and plant metabolism are available in the model plant Arabidopsis but somewhat lacking in major crops. Hence, a complete understanding of the molecular mechanisms by which staple crops respond to cold stress remain largely unknown. Here, we make an effort to elaborate on the molecular mechanisms employed in response to low-temperature stress. We summarize the effects of cold stress on the growth and development of these crops, the mechanism of cold perception, and the role of various sensors and transducers in cold signaling. We discuss the progress in cold tolerance research at the genome, transcriptome, proteome, and metabolome levels and highlight how these findings provide opportunities for designing cold-tolerant crops for the future.
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Proteínas de Plantas , Factores de Transcripción , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Productos Agrícolas/genética , Frío , Respuesta al Choque por FríoRESUMEN
Among the deadliest diseases, cancer is characterized by tumors or an increased number of a specific type of cell because of uncontrolled divisions during mitosis. Researchers in the current era concentrated on the development of highly selective anticancer medications due to the substantial toxicities of conventional cytotoxic drugs. Several marketed drug molecules have provided resistance against cancer through interaction with certain targets/growth factors/enzymes, such as Telomerase, Histone Deacetylase (HDAC), Methionine Aminopeptidase (MetAP II), Thymidylate Synthase (TS), Glycogen Synthase Kinase-3 (GSK), Epidermal Growth Factor (EGF), Vascular Endothelial Growth Factor (VEGF), Focal Adhesion Kinase (FAK), STAT3, Thymidine phosphorylase, and Alkaline phosphatase. The molecular structure of these drug molecules contains various heterocyclic moieties that act as pharmacophores. Recently, 1,3,4- oxadiazole (five-membered heterocyclic moiety) and its derivatives attracted researchers as these have been reported with a wide range of pharmacological activities, including anti-cancer. 1,3,4- oxadiazoles have exhibited anti-cancer potential via acting on any of the above targets. The presented study highlights the synthesis of anti-cancer 1,3,4-oxadiazoles, their mechanism of interactions with targets, along with structure-activity relationship concerning anti-cancer potential.
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Antineoplásicos , Neoplasias , Humanos , Oxadiazoles/farmacología , Oxadiazoles/uso terapéutico , Factor A de Crecimiento Endotelial Vascular , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Estructura Molecular , Relación Estructura-Actividad , Neoplasias/tratamiento farmacológicoRESUMEN
The 26S proteasome is a molecular machine that catalyzes and degrades protein intracellularly with the help of its core complex called 20S proteasome. The 20S proteasomes degrade and cleave denatured, cytotoxic, damaged, and unwanted proteins via proteolysis and impart biotic and abiotic stress tolerance in model plants. This study identified 20 genes, namely, 10 SbPA and 10 SbPB that encode for α- and ß-subunits of the 20S proteasome in Sorghum bicolor (L.) Moench (2n= 20). These genes have been found distributed on the 1st, 2nd, 3rd, 4th, 5th, 7th, and 10th chromosomes. These sorghum genes were orthologous to corresponding rice. Phylogenetic analysis clustered these genes into seven clades, each with one of the seven α-subunits (1 to 7) and one of the seven ß-subunits (1 to 7). In silico gene expression analysis suggested that nine genes were involved in abiotic stress response (cold, drought, and abscisic acid hormone). The expression of these proteasomal genes was studied in shoots and roots exposed to different abiotic stresses (cold, drought, and abscisic acid) by quantitative real-time polymerase chain reaction. A significant increase in the relative fold expression of SbPBA1, SbPAA1, SbPBG1, SbPBE1, and SbPAG1 genes under ABA and drought stress provides an insight into its involvement in abiotic stress. No expression was observed for cold stress of these genes indicating their non-involvement. It is believed that additional investigation into the SbPA/SbPB genes would aid in the creation of S. bicolor cultivars that are resistant to climate change.
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Plant tissue culture is the primary, fundamental, and applied aspect of plant biology. It is an indispensable and valuable technique for investigating morphogenesis, embryogenesis, clonal propagation, crop improvements, generation of pathogen-free plants, gene transfer and expression, and the production of secondary metabolites. The extensive use of various nanoparticles (NPs) in fields such as cosmetics, energy, medicine, pharmaceuticals, electronics, agriculture, and biotechnology have demonstrated positive impacts in microbial decontamination, callus differentiation, organogenesis, somatic variations, biotransformation, cryopreservation, and enhanced synthesis of bioactive compounds. This review summarizes the current state of knowledge with regard to the use of nanoparticles in plant tissue culture, with a particular focus on the beneficial outcomes. The positive (beneficial) and negative (toxic) effects of engineered NPs in tissue culture medium, delivery of transgenes, NPs toxicity concerns, safety issues, and potential hazards arising from utilization of nanomaterials in agriculture through plant tissue culture are discussed in detail, along with the future prospects for these applications. In addition, the potential use of novel nanomaterials such as graphene, graphite, dendrimers, quantum dots, and carbon nanotubes as well as unique metal or metalloid NPs are proposed. Further, the potential mechanisms underlying NPs elicitation of tissue culture response in different applications are critically evaluated. The potential of these approaches in plant nanobiotechnology is only now becoming understood and it is clear that the role of these strategies in sustainably increasing crop production to combat global food security and safety in a changing climate will be significant.
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The role of biochar in improving the soil properties of problem soils is well known, but its long term impact on lowland rice soil is not well recognized. The soil quality indicators of biochar applied lowland rice soil are not widely reported. We developed soil quality index (SQI) of a biochar applied lowland rice soil based on 17 soil properties (indicators). Field experimentation consisted of six treatments such as 0.5, 1, 2, 4, 8 and 10 t ha-1 of rice husk derived biochar (RHB) along with control. An overall SQI was calculated encompassing the indicators using multivariate statistics (principal component analysis) and non-linear scoring functions after generation of minimum data set (MDS). Sequential application of RHB improved the SQI by 4.85% and 16.02% with application of 0.5 t ha-1 and 10 t ha-1 RHB, respectively, over the recommended dose of fertilizer (control). PCA-screening revealed that total organic carbon (Ctot), zinc (Zn), pH and bulk density (BD) were the main soil quality indicators for MDS with 27.79%, 26.61%, 23.67% and 14.47% contributions, respectively. Apart from Ctot, Zn is one of the major contributors to SQI and RHB application can potentially be an effective agronomic practice to improve Zn status in lowland rice soil. The overall SQI was significantly influenced by RHB application even at 0.5 t ha-1. The present study highlights that application of RHB improves the soil quality even in fertile, well managed, lowland rice soil.
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Soil microbial communities are important drivers of biogeochemical cycling of nutrients, organic matter decomposition, soil organic carbon, and Greenhouse gas emissions (GHGs: CO2, N2O, and CH4) and are influenced by crop and soil management practices. The knowledge on the impact of conservation agriculture (CA) on soil bacterial diversity, nutrient availability, and GHG emissions in semi-arid regions under rainfed conditions is vital to develop sustainable agricultural practices, but such information has not been systemically documented. Hence, studies were conducted for 10 years in rainfed pigeonpea (Cajanus cajan L.)-castor bean (Ricinus communis L.) cropping system under semi-arid conditions to assess the effects of tillage and crop residue levels on the soil bacterial diversity, enzyme activity (Dehydrogenase, urease, acid phosphatase, and alkaline phosphatase), GHG emissions, and soil available nutrients (Nitrogen, phosphorus, and potassium). Sequencing of soil DNA through Illumina HiSeq-based 16S rRNA amplicon sequencing technology has revealed that bacterial community responded to both tillage and residue levels. The relative abundance of Actinobacteria in terms of Operational Taxonomic Unit (OTUs) at phyla, class as well as genera level was higher in CA (NTR1: No Tillage + 10 cm anchored residue and NTR2 NT + 30 cm anchored residue) over CT (conventional tillage without crop residues). CA resulted in higher enzyme activities (dehydrogenase, urease, acid phosphatase, and alkaline phosphatase) and reduction in GHG emissions over CT. CA recorded 34% higher and 3% lower OC, as compared to CT, and CTR1, respectively. CA recorded 10, 34, and 26% higher available nitrogen, phosphorus, and potassium over CT and CTR1, respectively. NTR1 recorded 25 and 38% lower N2O emissions as compared to CTR1 and CTR2, respectively. Whereas only NT recorded 12% higher N2O emissions as compared to CT. Overall, the results of the study indicate that CA improves the relative abundance of soil bacterial communities, nutrient availability, and enzyme activities, and may help to contribute to the mitigation of climate change, and sustainability in rainfed areas.
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Hair and nails are human biomarkers capable of providing a continuous assessment of the concentrations of elements inside the human body to indicate the nutritional status, metabolic changes, and the pathogenesis of various human diseases. Laser-induced breakdown spectroscopy (LIBS) and X-ray fluorescence (XRF) spectrometry are robust and multi-element analytical techniques able to analyze biological samples of various kinds for disease diagnosis. The primary objective of this review article is to focus on the major developments and advances in LIBS and XRF for the elemental analysis of hair and nails over the last 10-year period. The developments in the qualitative and quantitative analyses of human hair and nail samples are discussed in detail, with special emphasis on the key aspects of elemental imaging and distribution of essential and non-essential elements within the hair and nail tissue samples. Microchemical imaging applications by LIBS and XRF (including micro-XRF and scanning electron microscopy, SEM) are also presented for healthy as well as diseased tissue hair and nail samples in the context of disease diagnosis. In addition, main challenges, prospects, and complementarities of LIBS and XRF toward analyzing human hair and nails for disease diagnosis are also thoroughly discussed here.
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Background: The coronavirus disease 2019 (COVID-19) pandemic has reached a staggering number of almost 280 million cases worldwide, with over 5.4 million deaths as of 29 December 2021. A further understanding of the factors related to the household spread of the infection might help to bring about specific protocols to curb such transmission. Objective: This study aims to find the secondary attack rate (SAR) and factors affecting SAR among the households of mild COVID-19 cases. Methods: An observational study was designed where data of patients admitted at All India Institute of Medical Sciences, New Delhi due to mild COVID-19 were collected, and outcome was noted after the discharge of the patient. Index cases who were the first in the household to have a positive infection only were included. Based on these data, the overall household SAR, factors related to the index case and contacts that affected transmissibility were noted. Results: A total of 60 index cases having contacts with 184 household members were included in the present study. The household SAR was measured to be 41.85%. At least one positive case was present in 51.67% households. Children below 18 years old had lower odds of getting a secondary infection compared to adults and elderly [odds ratio (OR) = 0.46, 95%CI = 0.22-0.94, p = 0.0383). An exposure period of more than a week was significantly associated with a higher risk of infection (p = 0.029). The rate of transmissibility drastically declined with effective quarantine measures adopted by the index case (OR = 0.13, 95%CI = 0.06-0.26, p < 0.00001). Symptomatic index cases contributed more to the SAR than asymptomatic primaries (OR = 4.74, 95%CI = 1.03-21.82, P = 0.045). Healthcare worker index cases had lower rates of spread (OR = 0.29, 95%CI = 0.15-0.58, P = 0.0003). Conclusion: The high SAR shows the household is a potential high-risk unit for transmissibility of COVID-19. Proper quarantine measures of all those exposed to the index case can mitigate such spread and lead to reduction of risk of COVID-19 within a household.
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1,2,5-oxadiazole belongs to five-membered heterocyclic compounds with two nitrogen and one oxygen atom. In comparison with other heterocyclic moieties, 1,2,5-oxadiazoles moiety is considered as underprivileged as it attracted little attention of the researchers although lot of scopes and possible applications in medicinal, material and agriculture science. 1,2,5-oxadiazole and its derivatives have been reported as good pharmacophores as carbonic anhydrase inhibitors, antibacterial, vasodilating agents, antimalarial, anticancer, etc. In the presented manuscript, we reviewed granted patents and different synthetic strategies which have been reported for the synthesis of 1,2,5-oxadiazoles such as cycloaddition, dimerization, cyclodehydration, condensation, thermolysis, nitration, oxidation and ring-conversion. These synthetic methods have also been analysed for their merits and demerits. The manuscript also highlighted various applications of 1,2,5-oxadiazole and its derivatives. We hope that researchers across the scientific streams will be benefitted from the presented review articles for designing their work related to 1,2,5-oxadiazoles.
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Antimaláricos , Oxadiazoles , Oxadiazoles/farmacología , Inhibidores de Anhidrasa Carbónica , Antimaláricos/farmacología , Oxidación-Reducción , Relación Estructura-ActividadRESUMEN
BACKGROUND: Yellow or stripe rust, caused by the fungus Puccinia striiformis f. sp. tritici (Pst) is an important disease of wheat that threatens wheat production. Since developing resistant cultivars offers a viable solution for disease management, it is essential to understand the genetic basis of stripe rust resistance. In recent years, meta-QTL analysis of identified QTLs has gained popularity as a way to dissect the genetic architecture underpinning quantitative traits, including disease resistance. RESULTS: Systematic meta-QTL analysis involving 505 QTLs from 101 linkage-based interval mapping studies was conducted for stripe rust resistance in wheat. For this purpose, publicly available high-quality genetic maps were used to create a consensus linkage map involving 138,574 markers. This map was used to project the QTLs and conduct meta-QTL analysis. A total of 67 important meta-QTLs (MQTLs) were identified which were refined to 29 high-confidence MQTLs. The confidence interval (CI) of MQTLs ranged from 0 to 11.68 cM with a mean of 1.97 cM. The mean physical CI of MQTLs was 24.01 Mb, ranging from 0.0749 to 216.23 Mb per MQTL. As many as 44 MQTLs colocalized with marker-trait associations or SNP peaks associated with stripe rust resistance in wheat. Some MQTLs also included the following major genes- Yr5, Yr7, Yr16, Yr26, Yr30, Yr43, Yr44, Yr64, YrCH52, and YrH52. Candidate gene mining in high-confidence MQTLs identified 1,562 gene models. Examining these gene models for differential expressions yielded 123 differentially expressed genes, including the 59 most promising CGs. We also studied how these genes were expressed in wheat tissues at different phases of development. CONCLUSION: The most promising MQTLs identified in this study may facilitate marker-assisted breeding for stripe rust resistance in wheat. Information on markers flanking the MQTLs can be utilized in genomic selection models to increase the prediction accuracy for stripe rust resistance. The candidate genes identified can also be utilized for enhancing the wheat resistance against stripe rust after in vivo confirmation/validation using one or more of the following methods: gene cloning, reverse genetic methods, and omics approaches.
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Basidiomycota , Triticum , Triticum/genética , Triticum/microbiología , Pan , Fitomejoramiento , Sitios de Carácter Cuantitativo , Mapeo Cromosómico , Resistencia a la Enfermedad/genética , Basidiomycota/genética , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiologíaRESUMEN
Simple, versatile, and catalyst-free synthetic methods for ß-keto dithiocarbamates, thiazolidine-2-thiones, and thiazole-2-thiones via the multicomponent reaction of CS2, amines, and sulfoxonium ylides have been described. The ß-keto sulfoxonium ylides furnished ß-keto dithiocarbamates in the presence of CS2 and secondary amines, whereas primary amines afforded thiazolidine-2-thiones or thiazole-2-thiones after dehydration in an acidic environment. With simple procedures, the reaction has a wide substrate scope and excellent functional group tolerance.
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BACKGROUND: Nitrogen (N) and phosphorous (P) play a very important role in the growth and development of wheat as well as major constituents of biological membranes. To meet the plant's nutritional demand these nutrients are applied in the form of fertilizers. But the plant can utilize only half of the applied fertilizer whereas the rest is lost through surface runoff, leaching and volatilization. Thus, to overcome the N/P loss we need to elucidate the molecular mechanism behind the N/P uptake. METHODS: In our study, we used DBW16 (low NUE), and WH147 (high NUE) wheat genotypes under different doses of N, whereas HD2967 (low PUE) and WH1100 (high PUE) genotypes were studied under different doses of P. To check the effect of different doses of N/P, the physiological parameters like total chlorophyll content, net photosynthetic rate, N/P content, and N/PUE of these genotypes were calculated. In addition, gene expression of various genes involved in N uptake, utilization, and acquisition such as Nitrite reductase (NiR), Nitrate transporter 1/Peptide transporter family (NPF2.4/2.5), Nitrate transporter (NRT1) and NIN Like Protein (NLP) and induced phosphate starvation (IPS), Phosphate Transporter (PHT1.7) and Phosphate 2 (PHO2) acquisition was studied by quantitative real-time PCR. RESULTS: Statistical analysis revealed a lower percent reduction in TCC, NPR, and N/P content in N/P efficient wheat genotypes (WH147 & WH1100). A significant increase in relative fold expression of genes under low N/P concentration was observed in N/P efficient genotypes as compared to N/P deficient genotypes. CONCLUSION: Significant differences in physiological data and gene expression among N/ P efficient and deficient wheat genotypes could be useful for future improvement of N/P use efficiency.