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In the Indian Sundarban, multiple attributes and interactions of natural hazards, exposure, and vulnerability pose severe threats to lives and livelihoods. Understanding the cause-and-effect relationships contributing to the risk of loss of sustainable livelihoods has become imperative but has not yet been holistically explored in a single study that provides a broader picture of all possible complex interactions. This study used the impact chain tool to holistically understand the risk that manifests as a result of interactions of hazards, exposure, and vulnerability. The secondary literature and authors' observations helped us structure the first draft of the impact chain, which was further developed and validated through fourteen gender-disaggregated interviews with key informants and delta dwellers. This validation process identified the complex interconnections contributing to risk as experienced by experts and delta dwellers, which is seldom reflected through exclusively quantitative data. A quantitative analysis of the qualitative data strongly indicated that tropical cyclones, rainfall variability, and storms are the dominant hazards that affect social–ecological vulnerability manifested through mangrove degradation, land loss due to erosion, and embankment breaching. Social vulnerability is caused by processes and factors that are either directly or indirectly influenced by natural hazards and social–ecological factors. Processes such as increasing seasonal male migration, uncertain agricultural income, and a lack of hazard-resistant housing exacerbates social vulnerability. Embankment breaching, the salinization of land and water, land loss due to erosion, mangrove degradation, land conversion, and groundwater abstraction were identified as the fundamental threats that can lead to a loss of sustainable livelihoods of the people if left unaddressed. [ABSTRACT FROM AUTHOR]

Jute is an important crop of the Indian subcontinent and comprises tossa jute (Corchorus olitorius) and white jute (C. capsularis). The yield and fiber quality of this crop remained stagnant for many years and could not be improved through conventional plant breeding. Also, no effort has been made to develop molecular markers on a scale required for marker-assisted selection (MAS) to supplement conventional plant breeding. As a first step toward deploying MAS for jute improvement, 2469 simple sequence repeats (SSRs) were developed in tossa jute (JRO 524) using four SSR-enriched genomic libraries. A random subset of 100 SSRs (25 SSRs from each library) was used to detect polymorphism between the parental genotypes of each of the two recombinant inbred line (RIL) mapping populations. The RILs are being developed from JRO 524 x PPO4 (for fiber fineness) and JRC 321 x CMU 010 (for lignin content) crosses to prepare molecular maps and conduct quantitative trait loci (QTL) analyses. Both SSR length polymorphism and [+ or -] polymorphism (null alleles, i.e., presence and absence of specific SSR) were detected; 50 SSRs detected polymorphism between the two genotypes of tossa jute, whereas 45 SSRs detected polymorphism between the two genotypes of white jute. This SSR allelic polymorphism in jute is higher than that reported in other crops and is adequate for construction of genetic maps for QTL analysis. The large-scale SSRs will also prove useful in studying genetic diversity, population structure, and association mapping.

Abstract Background Phosphatidylinositol 3-phosphate is involved in regulation of several key cellular processes, mainly endocytosis, signaling, nuclear processes, cytoskeletal remodelling, cell survival, membrane trafficking, phagosome maturation and autophagy. In most cases effector proteins bind to this lipid, using either FYVE or PX domain. These two domains are distributed amongst varied life forms such as virus, protists, fungi, viridiplantae and metazoa. As the binding ligand is identical for both domains, the goal of this study was to understand if there is any selectivity for either of these domains in different taxa. Further, to understand the different cellular functions that these domains may be involved in, we analyzed the taxonomic distribution of additional domains that associate with FYVE and PX. Results There is selectivity for either FYVE or PX in individual genomes where both domains are present. Fungi and metazoa encode more PX, whereas streptophytes in viridiplantae encode more FYVE. Excess of FYVE in streptophytes results from proteins containing RCC1and DZC domains and FYVE domains in these proteins have a non-canonical ligand-binding site. Within a taxonomic group the selected domain associates with a higher number of other domains and is thus expected to discharge a larger number of cellular functions. Also, while certain associated domains are present in all taxonomic groups, most of them are unique to a specific group indicating that while certain common functions are discharged by these domains in all taxonomic groups, some functions appear to be group specific. Conclusions Although both FYVE and PX bind to PtdIns(3)P, genomes of different taxa show distinct selectivity of encoding either of the two. Higher numbers of taxonomic group specific domains co-occur with the more abundant domain (FYVE/PX) indicating that group-specific rare domain architectures might have emerged to accomplish certain group-specific functions.

In this study the electron transfer theory for the high frequency intramolecular mode and low frequency medium mode has been rederived using different methods. For a single-mode case when the reactant surface is not in a thermal equilibrium but in a thermocoherent state the authors have derived the rate and discussed about the quantum features of the rate. In the limit of very low and very high temperatures the expressions are derived analytically and compared with the case of thermal distribution. Secondly, a Franck-Condon factor for a multimode displaced, distorted, and Duschinsky rotated adiabatic potential surfaces has been derived to obtain the rate. Lastly, a systematic investigation is made to show the temperature dependence on the rate due to displacement, distortion, and Duschinsky rotation of the harmonic potential energy surfaces of the reactant and product manifold. [ABSTRACT FROM AUTHOR]

We consider the cooling of vibrational degrees of freedom in a photoinduced excited electronic state of a model molecular system. For the various parameters of the potential surfaces of the ground and excited electronic states and depending on the excitation frequency of a single-mode laser light, the average energy or average vibrational temperature of the excited state passes through a minimum. The amount of cooling is quantified in terms of the overlap integral between the ground and excited electronic states of the molecule. We have given an approach to calculate the Franck-Condon factor for a multimode displaced-distorted-rotated oscillator surface of the molecular system. This is subsequently used to study the effect of displacement, distortion, and Duschinsky rotation on the vibrational cooling in the excited state. The absorption spectra and also the average energy or the effective temperature of the excited electronic state are studied for the above model molecular system. Considering the non-Condon effect for the symmetry-forbidden transitions, we have discussed the absorption spectra and average temperature in the excited-state vibrational manifold. [ABSTRACT FROM AUTHOR]

Background: Phosphatidylinositol 3-phosphate is involved in regulation of several key cellular processes, mainly endocytosis, signaling, nuclear processes, cytoskeletal remodelling, cell survival, membrane trafficking, phagosome maturation and autophagy. In most cases effector proteins bind to this lipid, using either FYVE or PX domain. These two domains are distributed amongst varied life forms such as virus, protists, fungi, viridiplantae and metazoa. As the binding ligand is identical for both domains, the goal of this study was to understand if there is any selectivity for either of these domains in different taxa. Further, to understand the different cellular functions that these domains may be involved in, we analyzed the taxonomic distribution of additional domains that associate with FYVE and PX. Results: There is selectivity for either FYVE or PX in individual genomes where both domains are present. Fungi and metazoa encode more PX, whereas streptophytes in viridiplantae encode more FYVE. Excess of FYVE in streptophytes results from proteins containing RCC1and DZC domains and FYVE domains in these proteins have a non-canonical ligand-binding site. Within a taxonomic group the selected domain associates with a higher number of other domains and is thus expected to discharge a larger number of cellular functions. Also, while certain associated domains are present in all taxonomic groups, most of them are unique to a specific group indicating that while certain common functions are discharged by these domains in all taxonomic groups, some functions appear to be group specific. Conclusions: Although both FYVE and PX bind to PtdIns(3)P, genomes of different taxa show distinct selectivity of encoding either of the two. Higher numbers of taxonomic group specific domains co-occur with the more abundant domain (FYVE/PX) indicating that group-specific rare domain architectures might have emerged to accomplish certain group-specific functions. [ABSTRACT FROM AUTHOR]

We have studied the absorption spectrum of a displaced distorted oscillator molecular system where the lower electronic state is in thermal equilibrium. In this occasion a method is devised to calculate the Franck–Condon factor through the use of displacement and squeezing operators. The relative rate of single vibronic level transitions from an excited electronic state to another excited electronic state is also studied. In both the cases the relevant effect of temperature, displacement and ratio of curvatures of the potential surfaces are investigated. The state-to-state transition in multimode system is analyzed in regard to the influence of energy gap and above parameters. [Copyright &y& Elsevier]

Aim: Cigarette smoking is a major risk for developing atherosclerosis; however, the underlying mechanism is poorly understood. This paucity of knowledge is largely attributed to the lack of an animal model; therefore, our efforts were targeted towards establishing cigarette smoke (CS)-induced atherosclerosis in guinea pig. To understand the mechanism, we investigated apoptosis, an event implicated in atherosclerosis, in the aorta of CS-exposed animals. Since a major deleterious effect of CS is oxidative stress, we also examined the effect of vitamin C, an antioxidant, on CS- induced atherosclerosis., Methods and Results: Guinea pigs on a diet with or without vitamin C supplement were exposed to CS for different time periods. Aortal sections from these animals were examined for atherosclerotic changes by staining with H&E and Oil red O. Atherogenic changes were observed in sections obtained from CS-exposed guinea pigs only. TUNEL assay showed the occurrence of apoptosis in CS-exposed guinea pig aorta. Our results revealed that CS-induced apoptosis could contribute to the progression but not to the initiation of the disease. Immunohistochemical analysis documents that CS-induced apoptosis in aortal sections is mediated at least in part by an increased Bax/Bcl2 ratio. In contrast, CS-exposed guinea pigs fed with vitamin C-supplemented diet exhibit little or no atherogenic changes. This anti-atherosclerotic activity of vitamin C can be attributed partly to its ability to inhibit CS-induced apoptosis and platelet activation., Conclusion: Exposure of guinea pigs to cigarette smoke causes the development of atherosclerosis, which can be prevented by vitamin C supplement.

When a finite quantum system, say a fluorescent molecule is attached to a bulk surface and excited by a short laser pulse, the decay dynamics of the system is modulated by the surface and the signal is enhanced due to the bulk surface. We have considered the decay dynamics of a model of displaced distorted molecule whose excited potential surface is coupled to a continuum and then this first continuum is in turn coupled to a second continuum. In the short time scale there is a coherent exchange of energy between the system molecule and the first continuum states. In the long time scale the energy of the whole system plus first continuum drains out to the final continuum states. A dendrimer nanocomposite with the gold surface shows an enhanced light emission. This can be qualitatively understood from the model we proposed here. We have numerically studied the various potential parameters of the molecule which can affect the signal. When the potential surfaces are flat, the band structure of the first continuum states along with its initial excitation has some nontrivial effect on the profile of the radiative decay.