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Abstract Earlier proxy‐observational studies, and a sole modeling study, suggest that the Indian Ocean Dipole (IOD), an important global climate driver, exhibited multi‐scale temporal variability during the Last Millennium (LM; CE 0851–1849, with relatively high number of strong positive IOD events during the Little Ice Age (LIA; CE 1550–1749), and strong negative IOD events during the Medieval Warm Period (MWP; CE 1000–1199). Using nine model simulations from the PMIP3, we study the IOD variability during the LM after due validation of the simulated current day (CE 1850–2005) IOD variability. Majority of the models simulate relatively higher number of positive IOD events during the MWP, and negative IOD events in the LIA, commensurate with simulated background conditions. However, higher number of strong positive IOD events are simulated relative to the negative IODs during the LIA, in agreement with proxy‐observations, apparently owing to increased coupled feedback during positive IODs.

Abstract The intra-seasonal variation in precipitation isotopes shows a characteristic declining trend over northeast India. As of now, no mechanism offers a consistent explanation of this trend. We have performed the isotopic analysis of precipitation (rain) and estimated net ecosystem exchange and latent heat fluxes using an eddy-covariance system in northeast India. Additionally, we have used a diagnostic model to determine the recycled rainfall in this region. We find a strong link between the enhanced ecosystem productivity and isotopic enrichment in rainwater during the premonsoon season. Subsequently, on the advent of monsoon, the Bay of Bengal generated moisture enters this region and depletes the isotopic values. Additionally, the regional-scale convective activities produce periodic lows in the precipitation isotopes. Contrary to the general understanding, our study shows that the internal factors, such as the local land-atmosphere interactions, rather than the external influences, play a significant role in governing the precipitation isotopes in northeast India.

Abstract Stable hydrogen isotopes in monsoonal precipitation (δDp) at three sites (Port Blair, Barisal and Darjeeling) reveal the factors governing δDp variations over a south‐north gradient across the Bay of Bengal. We found that the δDp at each site continuously decreases from May to September and these trends become more pronounced from south to north. The decreasing trends of downstream δDp closely follow the decreasing trends of upstream stable hydrogen isotopes in water vapor (δDv), which indicates that upstream δDv properties shape initial spatiotemporal patterns of the downstream δDp (“shaping effect”). Additionally, our results demonstrate that, during moisture transport, upstream vertical air motions (convection and downward motion) and topographic relief magnify the amplitude of the decreasing trends of downstream δDp (“magnifying effect”). Our findings imply that upstream δDv properties and relevant atmospheric and topographical conditions along the moisture transport pathway need to be considered collectively to better interpret paleoclimate records.

Abstract Using information contained in the eighteenth to twentieth century British administrative documents, preserved in the National Archives of India (NAI), we present a 218-year (1729–1947 AD) record of socioeconomic disruptions and human impacts (famines) associated with ‘rain failures’ that affected the semi-arid regions (SARs) of southern India. By mapping the southern Indian famine record onto long-term spatiotemporal measures of regional rainfall variability, we demonstrate that the SARs of southern India repeatedly experienced famines when annual rainfall reduced by ~ one standard deviation (1 SD), or more, from long-term averages. In other words, ‘rain failures’ listed in the colonial documents as causes of extreme socioeconomic disruptions, food shortages and human distress (famines) in the southern Indian SARs were fluctuations in precipitation well within the normal range of regional rainfall variability and not extreme rainfall deficits (≥ 3 SD). Our study demonstrates that extreme climate events were not necessary conditions for extreme socioeconomic disruptions and human impacts rendered by the colonial era famines in peninsular India. Based on our findings, we suggest that climate change risk assessement should consider the potential impacts of more frequent low-level anomalies (e.g. 1 SD) in drought prone semi-arid regions.

Abstract Amongst all the anthropogenically produced greenhouse gases (GHGs), carbon dioxide (CO2) and methane (CH4) are the most important, owing to their maximum contribution to the net radiative forcing of the Earth. India is undergoing rapid economic development, where fossil fuel emissions have increased drastically in the last three decades. Apart from the anthropogenic activities, the GHGs dynamics in India are governed by the biospheric process and monsoon circulation; however, these aspects are not well addressed yet. Towards this, we have measured CO2 and CH4 concentration at Sinhagad, located on the Western Ghats in peninsular India. The average concentrations of CO2 and CH4 observed during the study period are 406.05 ± 6.36 and 1.97 ± 0.07 ppm (µ ± 1σ), respectively. They also exhibit significant seasonal variabilities at this site. CH4 (CO2) attains its minimum concentration during monsoon (post-monsoon), whereas CO2 (CH4) reaches its maximum concentration during pre-monsoon (post-monsoon). CO2 poses significant diurnal variations in monsoon and post-monsoon. However, CH4 exhibits a dual-peak like pattern in pre-monsoon. The study suggests that the GHG dynamics in the western region of India are significantly influenced by monsoon circulation, especially during the summer season.

The tooth enamel from the human remains of ten archaeological individuals belonging to a chalcolithic site at Inamgaon, District Pune, Maharashtra, were analysed for stable carbon and oxygen isotope compositions. The human remains of the involved individuals come from three consecutive periods: Period I (1600–1400 BC; n = 2), Period II (1400–1000 BC; n = 4), and Period III (1000–700 BC; n = 4). Enamel carbonate of twenty teeth (n = 20), two from each individual, were analysed to understand the inter- and intra-individual variations in isotope ratios across the three habitational periods. The acquired dataset will help in understanding isotope baseline values for the region in the prehistoric context. The subsequent research works in the region can reuse our data in collation with other datasets for comparative investigations.

Codon usage bias (CUB) is a unique property of genome which refers to non-random usage of synonymous codons in coding sequences. The present study makes an attempt to find out the pattern of CUB in chloroplast (cp) genes among three tea species, i.e., Camellia sinensis var. assamica (Assam tea), Camellia sinensis var. sinensis (Chinese tea) and Camellia pubicosta (wild tea species) as no work on CUB was reported earlier. To understand the patterns of codon usage among the cp genes of three tea groups, we used bioinformatic tools to investigate the protein coding sequences of cp genes. In our present study, the mean nucleobase T was the highest whereas C was the lowest in all the three tea groups. The overall AT content was more than GC content, i.e., genes were AT rich. The scaled chi-square (SCS) value indicated that the CUB of cp genes was low. The codon CGT (Arg) was over-represented in C. sinensis var. sinensis whereas GGA (Pro) was over-represented in C. pubicosta species. Heatmap study revealed that most of the GC ending codons showed positive correlations between codon usage and GC3 while AT ending codons exhibited negative correlations. From neutrality plot analysis, it was evident that natural selection had played a major role, while mutation pressure exerted a minor effect in the CUB of cp genes in three tea groups. Highly significant (P

The given interview delves deep into the performative and psychological aspects of a female impersonator. Chapal Bhaduri was born a boy and he had an enriched theatrical background in his home. In this interview he talks about his initial performance, the struggles of his later life, and his role-playing as a female impersonator. The area of gender studies and gender and performativity are replete with numerous nuanced variations in terms of understanding the impact on the actor/actress on stage. Alterations and changing roles played by a man who impersonates a woman on stage, is therefore, liable to have an expansive outreach altogether. In this interview, Bhaduri also laments the current condition of the Indian yatra and the different types of media that have taken a toll on the traditional forms of theatre.

Abstract We present precipitation isotope data (δ2H and δ18O values) from 19 stations across the tropics collected from 2012 to 2017 under the Coordinated Research Project F31004 sponsored by the International Atomic Energy Agency. Rainfall samples were collected daily and analysed for stable isotopic ratios of oxygen and hydrogen by participating laboratories following a common analytical framework. We also calculated daily mean stratiform rainfall area fractions around each station over an area of 5° x 5° longitude/latitude based on TRMM/GPM satellite data. Isotope time series, along with information on rainfall amount and stratiform/convective proportions provide a valuable tool for rainfall characterisation and to improve the ability of isotope-enabled Global Circulation Models to predict variability and availability of inputs to fresh water resources across the tropics.

Abstract Among the natural ecosystems, forests and wetlands emit a sizable amount of carbon dioxide (CO2) and methane (CH4) through autotrophic and heterotrophic respiration and bacterial activities. Interestingly, some evidence suggests that a significant amount of CH4 is generated by the trees in forested ecosystems. The net ecosystem exchange (NEE), measured by the eddy covariance (EC) method, typically represents the net CO2 flux arising from the photosynthetic and respiration processes in the biosphere. This flux is subsequently partitioned into two components, the respired carbon and the assimilated carbon. However, the usual method of partitioning introduces significant errors in each of these fluxes. The present study was undertaken to address this issue where the NEE partitioning was constrained by using the carbon isotopic ratios of CO2. We used a real‐time in situ analyzer in a tropical forest in northeast India, the Kaziranga National Park. The greenhouse gas analyzer provided CO2 and CH4 concentrations, as well as their carbon isotopic ratios. The isotopic data were used to partition the EC‐derived NEE values and derive the isoflux values. Additionally, the isotopic data provided evidence of plant‐generated CH4 in conformity with some recent studies, which requires further investigation.

Proxy and model-based studies suggest multi-scale temporal variability in the Indian summer monsoon (ISM). In this study, using the CESM1 atmospheric general circulation model, we carried out multiple ensemble AGCM simulations for the Mid-Holocene (MH; ≈ 6 kyr BP), Medieval Warm Period (MWP; ≈ 1 kyr BP), Little Ice Age (LIA; ≈ 0.35 kyr BP), and Historical (HS; ≈ CE 2000) periods. We used the PMIP3/CMIP5 boundary conditions for this purpose. Our simulations indicate that the ISM during the MH was stronger compared to HS and the rainfall higher, in agreement with several proxy studies. The experiments also suggest that the ISM rainfall (ISMR) was higher during MWP relative to the LIA in agreement with our earlier results from the PMIP3 models. A relatively northward migration of the ITCZ over the Indian region and strengthening of the neighboring subtropical high over the northwestern Pacific, both associated with stronger insolation associated with the obliquity and precision during the MH, seem to be important reason Indian summer monsoon during the MH.

The carbon and oxygen isotopic composition of tooth enamel is connected to the diet and environment in which it develops. Enamel is invariably preserved for a long time and hence provides the best material for chemical analysis. Teeth are known to reflect a record of dietary and environmental changes taking place during their growth. This paper presents the results of intra-tooth oxygen and carbon isotope values (δ18O,δ13C) of first, second and third molars obtained from five modern cattle collected from two locations: Dhansi and Hathnora from the Central Narmada Valley, India. The specimens chosen for this study are individuals presumed to have died naturally and/or disposed of by local farmers. The isotopic analysis of tooth enamel is broadly indicative of a C3 diet with values of δ13C (enamel bioapatite) ranging from –6.4‰ VPDB to –27.31‰ VPDB with an average of –16.68‰ VPDB. The δ18O values measured in the enamel samples range between of 1.76‰ to 25.15‰ with a mean value of 22.17‰ VSMOW. These present day dental enamel values of modern cattle were compared against the published enamel isotope values of Bos namadicus, that occupied this region during the Pleistocene era, in order to understand the possible shift in diet and environment and their inter-relationship between the modern and the Pleistocene Era. The fossil sample produced enriched values of carbon isotopes compared to the modern taxa, indicating a C4 rich diet, while the diet of the modern cattle is extensively dominated by C3 type vegetation. We also observed an enriched oxygen isotope values for the fossil sample compared to the modern samples, indicating a possible effect of diagenesis and/or a shift in the temperature and rainfall.

Artificial intelligence (AI) systems hold great promise as decision-support tools, but we must be able to identify and understand their inevitable mistakes if they are to fulfill this potential. This is particularly true in domains where the decisions are high-stakes, such as law, medicine, and the military. In this Perspective, we describe the particular challenges for AI decision support posed in military coalition operations. These include having to deal with limited, low-quality data, which inevitably compromises AI performance. We suggest that these problems can be mitigated by taking steps that allow rapid trust calibration so that decision makers understand the AI system's limitations and likely failures and can calibrate their trust in its outputs appropriately. We propose that AI services can achieve this by being both interpretable and uncertainty-aware. Creating such AI systems poses various technical and human factors challenges. We review these challenges and recommend directions for future research. The Bigger Picture: This article is about artificial intelligence (AI) used to inform high-stakes decisions, such as those arising in legal, healthcare, or military contexts. Users must have an understanding of the capabilities and limitations of an AI system when making high-stakes decisions. Usually this requires the user to interact with the system and learn over time how it behaves in different circumstances. We propose that long-term interaction would not be necessary for an AI system with the properties of interpretability and uncertainty awareness. Interpretability makes clear what the system “knows” while uncertainty awareness reveals what the system does not “know.” This allows the user to rapidly calibrate their trust in the system's outputs, spotting flaws in its reasoning or seeing when it is unsure. We illustrate these concepts in the context of a military coalition operation, where decision makers may be using AI systems with which they are unfamiliar and which are operating in rapidly changing environments. We review current research in these areas, considering both technical and human factors challenges, and propose a framework for future work based on Lasswell's communication model.

Quantification of the genetic distance between populations is essential in many genetic research programs. Several formulae were proposed for the estimation of genetic distance between populations using gene frequency data. But the selection of a suitable measure for estimating genetic distance between real-world human populations is a very difficult task despite the widely used measure Neis D. The present study was undertaken to estimate the genetic distance between Barak Valley Muslims (BVM) and other twenty-four nations using seven different measures with ABO blood group gene frequency data for comparative analysis and to estimate the correlation coefficients between distance measures and to work out the linear regression equations. Seven genetic distance measures namely Neis D, Neis Nm, La, Neis Da, Dc, Re and Neis Ne were estimated between BVM and other 24 nations enroute the journey of mankind from Africa that commenced about 200,000 years ago (www.bradshawfoundation.com). Correlation coefficients between Neis D with other measures were estimated to find out which other genetic distance measures were closely related to Neis D. Neis D showed highly significant (p=0.01) positive correlation with Cavalli-Sforza and Edwards chord distance Dc (0.90), Reynolds Re (0.90), Neis Da (0.74) and Neis Ne (0.63) but negative correlation with Neis Nm and La. Linear regression equations of Neis D with other distance measures were estimated as Da = -0.80 + 1.34D, Dc = 1.91 + 4.44D, Re = -0.51 + 0.24D and Ne = -7.60 + 1.30D.

Polygenes (QTLs) for grain yield were mapped on rice chromosomes under two moisture stress environments by multiple interval mapping (MIM) method in a double haploid (DH) population derived from a cross between a deep-rooted japonica and a shallow-rooted indica genotype. In environment 1 (E1), the MIM detected a total of six QTLs for grain yield on chromosomes-two QTLs on chromosome 1 and four QTLs on chromosome 5 along with one additive x additive epistasis. But in environment 2 (E2), the MIM detected five QTLs for grain yield on two chromosomes-three QTLs on chromosome 1 and two QTLs on chromosome 7. One common QTL on chromosome 1 flanked by the markers RG109-ME1014 was detected in both the environments, although the other detected QTLs differed between environments. The magnitude of QTL effect, percent genetic variance and percent phenotypic variance explained by each QTL was also estimated in both environments. The common QTL explained about 26.05 and 13.93% of genetic variance in E1 and E2, respectively. Estimated broad sense heritability for grain yield was 48.01 in E1 and 25.27% in E2.

The present study aimed at estimating the genetic distance and genetic identity between Barak Valley Hindus and other twenty four nations for ABO blood group gene along the route of historic journey of mankind from Africa as proposed by Stephen Oppenheimer to gain insights on the evolutionary relationship and genetic closeness of the Hindus with other nations. Barak Valley Zone, located in southern part of Assam state in North East India, has inhabited the major endogamous group, the Hindus, for several centuries. Over the last few decades, they have maintained distinct culture and life style. This study used ABO gene frequency data of these populations to estimate Neis standard genetic distance and genetic identity of population genetics between Barak Valley Hindus and other nations. The historic journey of mankind commenced from Africa about 200,000 years ago (www.bradshawfoundation.com). Genetic distance estimate ranged from 0.07 to 5.18%. Barak Valley Hindus (BVH) showed relatively low genetic distance for ABO gene with the populations of Saudi Arabia (0.07%), India (0.13%), Borneo (0.40%), Russia (0.59%), Central Asia (0.60%), Siberia (0.60%), South China (0.71%) and Sri Lanka (0.93%) suggesting high genetic identity and possible evolutionary relationship of BVH during migration with these nations. But the BVH showed highest genetic distance with Australia (5.18%) followed by Norway (4.13%), Sudan (3.89%) and Sweden (3.60%) indicating low genetic identity of BVH with these nations. Migration was not the key determining factor in changing the ABO gene frequency in human populations.

QTL for days to flowering in rice under drought condition were mapped using a DH population derived from a cross between a deep-rooted upland adapted japonica genotype CT9993-5-10-1-M and a lowland adapted shallow-rooted moderately drought tolerant indica genotype IR62266-42-6-2. QTL mapping was performed following three different mapping models viz. simple (SIM), composite (CIM) and multiple mapping model (MIM) using WinQTL Cartographer version 2.5.006. SIM located 12 QTL for days to flowering spread over nine chromosomes whereas CIM and MIM each located 5 QTL with a threshold LOD score of 2.5. A comparison of the QTL detected by three different models identified five QTL that were common across at least two models for days to flowering. In MIM analysis, the detected QTL (qHD-1-b) between flanking markers (RG109 � ME1014) located on chromosome 1 recorded positive effect (1.4090) but the remaining four QTL had negative effect. The QTL (qHD-3-a) detected between flanking markers (RG104 � RG409) by both MIM and SIM in the present study was also reported earlier as linked with the marker RG104. The five common QTL detected by at least two models could be considered as stable QTL for days to flowering under drought and might be of practical use in marker assisted selection.

From a study of 28 human populations, linkage disequilibrium (LD) between ABO and Rh blood group loci in human genome were estimated using two different statistic of population genetics viz. D and Q. In general, the haplotypes iRh+ and iRh- were, on average, 2 to 3-fold and 1.1 to 1.8-fold more frequent respectively than the corresponding expected haplotype frequency in the populations under study. Expected haplotype frequencies were calculated for each population assuming equal frequencies of alleles at ABO and Rh loci. The observed frequency of IARh+ haplotype was more or less close to the expected frequency (0.165). The haplotypes IARh-, IBRh+ and IBRh- were less frequent than expected in the populations. The D value for haplotype iRh+ was positive for all the populations suggesting preponderance of this haplotype and hence non-random association between ABO and Rh loci. Q is a single measure of LD and suitable for estimation of LD between loci having multiple alleles. Q value ranged from 2.18 (Finland) to 8.07 (Hongkong). High LD, indicated by high Q, between ABO and Rh loci was observed in the populations of Hongkong, BV Muslims, Saudi Arabia, BV Hindus, India and Iceland. But the populations of Finland, Austria, Estonia, Poland and Israel showed low LD revealed by low Q between ABO and Rh loci.

In a genetic study of 26 human populations including 2 major endogamous populations (Hindus and Muslims) of Barak Valley in Assam and 24 exotic populations, observed heterozygosity (Ho), fixation index (F) and Panmictic index (P) for ABO gene were estimated from gene frequency data to reveal the extent of inbreeding that has taken place in each population during evolution. Observed heterozygosity, a measure of genetic variation, ranged from 0.3254 to 0.6086 in these populations. Expected Hardy-Weinberg heterozygosity of ABO gene was estimated as 0.6666 assuming the occurrence of all the three alleles in equal frequency. Fixation index was the highest in the population of Sudan (51.18%) followed by Australia (48.51%) and Iceland (38.28%) indicating the occurrence of high inbreeding and the presence of more homozygosity in these populations during evolution. But the fixation index was the lowest in the population of South China (8.70%) followed by Central Asia (11.82%) and Russia (12.96%). It suggested the occurrence of low inbreeding and hence more outbreeding in these populations resulting in the existence of more heterozygosity (high genetic variation) in these populations. Panmictic index, a measure of outbreeding, is the opposite of fixation index and it varied from 48.82 (Sudan) to 91.30% (South China). The population showing the highest fixation index recorded the lowest panmictic index and vice-versa. In evolutionary context, outbreeding in human populations would be more desirable to reduce the incidence of genetic diseases caused by recessive genes and to enhance heterozygosity for those loci for better adaptation of future generations, possibly at the cost of gradually increasing genetic load in the population.

Quantification of the genetic distance between populations is essential in many genetic research programs. Several formulae have been proposed for the estimation of the genetic distance between populations using gene frequency data. Nei�s D has been the most widely used genetic distance measure in different research programs. But the selection of a suitable measure to estimate genetic distance between real-world human populations is a very difficult task. The present study was undertaken to estimate the genetic distance between Barak Valley Muslims (BVM) and other twenty four nations with the ABO blood group gene frequency data using seven different formulae, as well as to estimate the correlation coefficients between distance measures and to work out the regression equations. Seven genetic distance measures namely Nei�s D, Nei�s Nm, La, Nei�s Da, Dc, Re and Nei�s Ne were calculated between BVM and other 24 nations. Correlation coefficients of Nei�s D with other measures were determined to find out which other genetic distance measures were similar to Nei�s D. Linear regression equations of Nei�s D with other distance measures were determined. Nei�s D showed a highly significant (p=0.01) positive correlation with Cavalli-Sforza and Edwards chord distance Dc (0.90), Reynolds Re (0.90), Nei�s Da (0.74) and Nei�s Ne (0.63) but a negative correlation with Nei�s Nm and La. Since Nei�s D had very high positive correlation with Dc and Re distance measures, any one of these measures could be reliably used in genetic analysis instead of all the three measures for estimating genetic distance between populations.

The frequency of RhD and Rhd alleles of Rh blood group gene was estimated in 44 human populations distributed all over the world from the RhD phenotypic data. The average frequency of RhD and Rhd allele over these populations was 0.70 and 0.30, respectively. Higher frequency of RhD allele than the expected estimate (0.50) in all the populations, under Hardy-Weinberg equilibrium condition assuming equal frequency of both alleles in the initial population, indicated inbreeding at RhD/d locus as well as natural selection for RhD allele. Very high heritability estimate (84.04%) of Rh allele frequency revealed that this trait was under weak selection pressure and resulted in greater genetic variation in existing populations. It is consistent with Fisher�s fundamental theorem of natural selection. The results from the present study suggest that inbreeding at RhD/d locus and some other factors (possibly mutation, migration and genetic drift) other than natural selection alone played major roles in changing the Rh allele frequency in these populations.

A genetic study was carried out in two endogamous populations namely Hindus and Muslims in the Barak Valley Zone of Assam in India. Neis genetic distance and genetic identity between two populations were calculated on the basis of estimated allele frequencies of ABO and Rh blood group genes. The genetic distance between Hindus and Muslims was 0.12% for ABO gene and 0.10% for Rh gene. The genetic identity between two populations was estimated as 99.88% for ABO gene and 99.90% for Rh gene suggesting very high genetic similarity between these two populations. Observed heterozygosity estimate was higher in Hindus (0.5598 for ABO gene and 0.2822 for Rh gene) than Muslims (0.5346 for ABO gene and 0.2408 for Rh gene) indicating lesser inbreeding in Hindus than Muslims. Fixation index was lower in Hindus (16.02% for ABO gene and 43.56% for Rh gene) than Muslims (19.80% for ABO gene and 51.84% for Rh gene). Panmictic index was higher in Hindus than Muslims for both the genes. Fixation and panmictic indices revealed that during evolutionary process the Hindus maintained more outbreeding feature than the Muslims in the valley. In this study, the concepts of genetic load of a population and genotype fitness were extended to alleles to estimate the magnitude of allele genetic load (GL) and allele fitness for 3 alleles in ABO gene and for 2 alleles in Rh gene in two populations. The genetic load for O, A and B alleles were lower in Hindus than Muslims. Similar results for genetic load were found for the alleles of Rh gene in the comparison of two populations. The fitness estimates of O, A and B alleles for ABO gene and D and d alleles for Rh gene were higher in Hindus than Muslims. A population with low allele genetic load (GL) and high allele fitness (AF) might have greater survival advantage in nature in the absence of heterozygote advantage and higher adaptive value of the allele with increased frequency.

Line x tester analysis was carried out in black gram [Vigna mungo (L.) Hepper], an edible legume, to estimate the gca (general combining ability) effects of parents (3 lines and 3 testers) and the SCA (specific combining ability) effects of 9 crosses for seed yield and other eleven quantitative traits. Though additive and nonadditive gene actions governed the expression of quantitative traits, the magnitude of nonadditive gene action was higher than that of additive gene action for each quantitative trait. Two parents viz. UG157 and DPU915 were good general combiners. Two crosses namely PDB 88-31/DPU 915 and PLU 277/KAU7 had high per se performance along with positive significant SCA effect for seed yield/plant. The degree of dominance revealed overdominance for all the traits except clusters/plant with partial dominance. The predictability ratio also revealed the predominant role of nonadditive gene action in the genetic control of quantitative traits. Narrow sense heritability was also low for each trait. Recurrent selection or biparental mating followed by selection which can exploit both additive and nonadditive gene actions would be of interest for yield improvement in black gram. Due to presence of high magnitude of nonadditive gene action, heterosis breeding could also be attempted to develop low cost hybrid variety using genetic male sterility system in black gram.

The genetic study was carried out on a sample of 1400 individuals in the Barak Valley Zone of Assam in India to estimate the gene frequency and the expected genotype frequency for Rh and ABO blood group systems in Hindu and Muslim populations separately. The Rh +ve blood group outnumbered Rh ve blood group in Hindus (97 and 3%) and Muslims (98 and 2%). The frequencies of A (Rh +ve) and a (Rh ve) alleles were 0.83 and 0.17 in Hindus and 0.86 and 0.14 in Muslims. For both of the populations, O blood group was the highest followed by B, A and AB. Both A and B blood groups occurred in almost equal proportions in these two populations. The frequencies of IA, IB and i alleles were almost same for Hindus (0.19, 0.21 and 0.60) and Muslims (0.18, 0.19 and 0.63). The estimates of chi-square tests for gene frequency and genotype frequency of Rh and ABO blood group systems showed non-significant differences between the two populations. This suggested that the Hindus and the Muslims might be genetically the same, despite cultural, religious and socio-economic differences. Similar magnitudes of existing gene and genotype frequencies of Rh and ABO blood group systems of Hindus and Muslims suggested that both the populations of Barak Valley might have diversified from the same common ancestors in the recent past augmented by socioeconomic, religious and cultural factors over time.

Twenty-nine genotypes of boro rice (Oryza sativa L.) were grown in a randomized block design with three replications in plots of 4m x 1m with a crop geometry of 20 cm x 20 cm between November-April, in Regional Agricultural Research Station, Nagaon, India. Quantitative data were collected on five randomly selected plants of each genotype per replication for yield/plant, and six other yield components, namely plant height, panicles/plant, panicle length, effective grains/panicle, 100 grain weight and harvest index. Mean values of the characters for each genotype were used for analysis of variance and covariance to obtain information on genotypic and phenotypic correlation along with coheritability between two characters. Path analyses were carried out to estimate the direct and indirect effects of boro rice�s yield components. The objective of the study was to identify the characters that mostly influence the yield for increasing boro rice productivity through breeding program. Correlation analysis revealed significant positive genotypic correlation of yield/plant with plant height (0.21), panicles/plant (0.53), panicle length (0.53), effective grains/panicle (0.57) and harvest index (0.86). Path analysis based on genotypic correlation coefficients elucidated high positive direct effect of harvest index (0.8631), panicle length (0.2560) and 100 grain weight (0.1632) on yield/plant with a residual effect of 0.33. Plant height and panicles/plant recorded high positive indirect effect on yield/plant via harvest index whereas effective grains/panicle on yield/plant via harvest index and panicle length. Results of the present study suggested that five component characters, namely harvest index, effective grains/plant, panicle length, panicles/plant and plant height influenced the yield of boro rice. A genotype with higher magnitude of these component characters could be either selected from the existing genotypes or evolved by breeding program for genetic improvement of yield in boro rice.

Combining ability analysis for grain yield and its components was carried out in eight parental diallel crosses of bold grained rice excluding reciprocals. The general combining ability (GCA) and specific combining ability (SCA) effects were significant for all the characters indicating the importance of both additive and non-additive gene effects in their inheritance. The parents Ranjit followed by Matonga and Monohar Sali contributed significantly to high GCA effect towards high grain yield per hill. The superior specific cross combinations for high grain yield per hill were Matonga/Bar Madhava, originated from high x low GCA combination followed by Dhola Mula/ Ranjit (low x high gca), Chandmoni/Hathi Sali (low x high GCA), Dhola Mula/Mala (low x low gca), Matonga/Mala (high x low GCA), Bar Madhava/Hathi Sali (low x high GCA) and Matonga/Hathi Sali (high x high GCA). Further, these crosses exhibited high SCA effects for some other characters as well.

TP53 gene is known as the "guardian of the genome" as it plays a vital role in regulating cell cycle, cell proliferation, DNA damage repair, initiation of programmed cell death and suppressing tumor growth. Non uniform usage of synonymous codons for a specific amino acid during translation of protein known as codon usage bias (CUB) is a unique property of the genome and shows species specific deviation. Analysis of codon usage bias with compositional dynamics of coding sequences has contributed to the better understanding of the molecular mechanism and the evolution of a particular gene. In this study, the complete nucleotide coding sequences of TP53 gene from eight different mammalian species were used for CUB analysis. Our results showed that the codon usage patterns in TP53 gene across different mammalian species has been influenced by GC bias particularly GC3 and a moderate bias exists in the codon usage of TP53 gene. Moreover, we observed that nature has highly favored the most over represented codon CTG for leucine amino acid but selected against the ATA codon for isoleucine in TP53 gene across all mammalian species during the course of evolution.

It is vital to unravel the codon usage bias in order to gain insights into the evolutionary forces dictating the viral evolution process. Influenza A virus has attracted attention of many investigators over the years due to high mutation rate and being cross-specific shift operational in the viral genome. Several authors have reported that the codon usage bias is low in influenza A viruses, citing mutational pressure as the decisive force shaping up the codon usage in these viruses. In this study, complete coding sequences of hemagglutinin genes for H1N1 subtype of influenza A virus have been explored for the possible codon usage bias acting upon these genes. The results indicate overall low bias with peaking ENC values. The GC content is found to be substantially low as against AT content in the silent codon sites. Significant correlations were observed in between the compositional parameters versus AT3, implying the possible role of the latter in shaping codon usage profile in the viral hemagglutinin. The data showed conspicuously that the sequences were A redundant with most codons preferring nucleotide A over others in the third synonymous codon site. The results indicated the pivotal role of compositional pressure affecting codon usage in this virus.