Prioritizing Tiger Conservation through Landscape Genetics and Habitat Linkages

Even with global support for tiger (Panthera tigris) conservation their survival is threatened by poaching, habitat loss and isolation. Currently about 3,000 wild tigers persist in small fragmented populations within seven percent of their historic range. Identifying and securing habitat linkages that connect source populations for maintaining landscape-level gene flow is an important long-term conservation strategy for endangered carnivores. However, habitat corridors that link regional tiger populations are often lost to development projects due to lack of objective evidence on their importance. Here, we use individual based genetic analysis in combination with landscape permeability models to identify and prioritize movement corridors across seven tiger populations within the Central Indian Landscape. By using a panel of 11 microsatellites we identified 169 individual tigers from 587 scat and 17 tissue samples. We detected four genetic clusters within Central India with limited gene flow among three of them. Bayesian and likelihood analyses identified 17 tigers as having recent immigrant ancestry. Spatially explicit tiger occupancy obtained from extensive landscape-scale surveys across 76,913 km² of forest habitat was found to be only 21,290 km². After accounting for detection bias, the covariates that best explained tiger occupancy were large, remote, dense forest patches; large ungulate abundance, and low human footprint. We used tiger occupancy probability to parameterize habitat permeability for modeling habitat linkages using least-cost and circuit theory pathway analyses. Pairwise genetic differences (F _ST) between populations were better explained by modeled linkage costs (r>0.5, p<0.05) compared to Euclidean distances, which was in consonance with observed habitat fragmentation. The results of our study highlight that many corridors may still be functional as there is evidence of contemporary migration. Conservation efforts should provide legal status to corridors, use smart green infrastructure to mitigate development impacts, and restore habitats where connectivity has been lost.     

Neuroprotective Effects of Withania somnifera on 4-Hydroxynonenal Induced Cell Death in Human Neuroblastoma SH-SY5Y Cells Through ROS Inhibition and Apoptotic Mitochondrial Pathway

Neurochemical Research - The antioxidant, anti-inflammatory, and anticancer activities of Withania somnifera (WS) are known for a long time. This study was aimed to examine whether WS also...     

Enhanced decolorization of Solar brilliant red 80 textile dye by an indigenous white rot fungus Schizophyllum commune IBL-06

An indigenously isolated white rot fungus, Schizophyllum commune IBL-06 was used to decolorize Solar brilliant red 80 direct dye in Kirk’s basal salts medium. In initial screening study, the maximum decolorization (84.8%) of Solar brilliant red 80 was achieved in 7 days shaking incubation period at pH 4.5 and 30 °C. Different physical and nutritional factors including pH, temperature and fungal inoculum density were statistically optimized through Completely Randomized Design (CRD), to enhance the efficiency of S. commune IBL-06 for maximum decolorization of Solar brilliant red 80 dye. The effects of inexpensive carbon and nitrogen sources were also investigated. Percent dye decolorization was determined by a reduction in optical density at the wavelength of maximum absorbance (λ_max, 590 nm). Under optimum conditions, the S. commune IBL-06 completely decolorized (100%) the Solar brilliant red 80 dye using maltose and ammonium sulfate as inexpensive carbon and nitrogen sources, respectively in 3 days. S. commune IBL-06 produced the three major ligninolytic enzymes lignin peroxidase (LiP), manganase peroxidase (MnP) and lacaase (Lac) during the decolorization of Solar brilliant red 80. LiP was the major enzyme (944 U/mL) secreted by S. commune IBL-06 along with comparatively lower activities of MnP and Laccase.     

Interbirth interval and litter size of free-ranging Bengal tiger (Panthera tigris tigris) in dry tropical deciduous forests of India

We studied the interbirth interval (IBI) and litter size of the population of free-ranging Bengal tigers (Panthera tigris tigris) in dry tropical deciduous forests in Ranthambhore Tiger Reserve (RTR), Rajasthan, and Pench Tiger Reserve (PTR), Madhya Pradesh, between April 2005 and June 2011. Data on 15 breeding females in RTR and nine breeding females in PTR were collected using camera trapping, direct observation and radio-telemetry. The mean?±?standard error of IBI (months) in RTR was 33.4?±?3.7 and in PTR was 25.2?±?1.8. A significant difference was observed between the mean IBI of tigresses in RTR and those in PTR (df?=?9, P?=?0.04). The estimated mean litter size in RTR was 2.3?±?0.1 and that in PTR was 2.9?±?0.2. There was a significant difference between the litter size in RTR and that in PTR (χ ²?=?12.04, P?=?0.017, df?=?4). Since RTR and PTR are the important source populations of tigers in the Western and Central Indian landscapes, we propose that the tigers in these reserves be monitored, particularly for reproductive traits that are essential for understanding aspects of their population ecology.     

Factors influencing the distribution of leopard in a semiarid landscape of Western India

Previously, factors governing distribution of leopard (Panthera pardus fusca) in forest habitats of the Indian subcontinent were unknown. The present study assessed the influence of different ecogeographic variables determining the distribution of leopards in and around Sariska Tiger Reserve through MaxEnt habitat suitability model based on camera trapping method. Camera trapping was used to collect presence/absence information in the study area from December 2008 to June 2010. Information of 11 macrohabitat characteristics and variables (habitat types, prey species, Normalized Difference Vegetation Index (NDVI), elevation, livestock, village, water source, etc.) were collected along with leopard presence data. The probability of presence of leopards increased with decreasing distance to water and increasing encounter rate of peafowl (Pavo cristatus), chital (Axis axis), sambar (Rusa unicolor), and wild pig (Sus scrofa). It was found that the probability of presence of leopards increased with increasing area of Zizyphus mixed forest patches and NDVI. Results of this study showed that the probability of presence of leopards was higher in habitat types with intermediate cover, high wild prey base, and water sources. They also indicated that leopards are not always ‘generalists’ showing some degree of specialization, at least in their choice of habitat, and this information is useful for conserving leopard in human-dominated landscapes.     

WRF-TMH: predicting transmembrane helix by fusing composition index and physicochemical properties of amino acids

Membrane protein is the prime constituent of a cell, which performs a role of mediator between intra and extracellular processes. The prediction of transmembrane (TM) helix and its topology provides essential information regarding the function and structure of membrane proteins. However, prediction of TM helix and its topology is a challenging issue in bioinformatics and computational biology due to experimental complexities and lack of its established structures. Therefore, the location and orientation of TM helix segments are predicted from topogenic sequences. In this regard, we propose WRF-TMH model for effectively predicting TM helix segments. In this model, information is extracted from membrane protein sequences using compositional index and physicochemical properties. The redundant and irrelevant features are eliminated through singular value decomposition. The selected features provided by these feature extraction strategies are then fused to develop a hybrid model. Weighted random forest is adopted as a classification approach. We have used two benchmark datasets including low and high-resolution datasets. tenfold cross validation is employed to assess the performance of WRF-TMH model at different levels including per protein, per segment, and per residue. The success rates of WRF-TMH model are quite promising and are the best reported so far on the same datasets. It is observed that WRF-TMH model might play a substantial role, and will provide essential information for further structural and functional studies on membrane proteins. The accompanied web predictor is accessible at http://111.68.99.218/WRF-TMH/.     

Extremely stable indole-3-glycerol-phosphate synthase from hyperthermophilic archaeon Pyrococcus furiosus

Extremophiles - The gene-encoding Indole-3-glycerol phosphate synthase, a key enzyme involved in the cyclization of 1-(o-carboxyphenylamino)-1-deoxyribulose 5-phosphate, from Pyrococcus furiosus...     

Chemistry, urease inhibition, and phytotoxic studies of binuclear vanadium(IV) complexes

Vanadium plays an important role in biological systems and exhibits a variety of bioactivities. In an effort to uncover the chemistry and biochemistry of vanadium with nitrogen- and oxygen-containing ligands, we report herein the synthesis and spectroscopic characterization of vanadium(IV) complexes with hydrazide ligands. Substituents on these ligands exhibit systematic variations of electronic and steric factors. Elemental and spectral data indicate the presence of a dimeric unit with two vanadium(IV) ions coordinated with two hydrazide ligands along with two H(2)O molecules. The stability studies of these complexes over time in coordinating solvent, DMSO, indicates binding of the solvent molecules to give [V2O2L2(H2O)2(DMSO)2]2+ (L=hydrazide ligand) and then conversion of it to a monomeric intermediate species, [VOL(DMSO)3]1+. Hydrazide ligands are inactive against urease, whereas vanadium(IV) complexes of these ligands show significant inhibitory potential against this enzyme and are found to be non-competitive inhibitors. These complexes also show low phytotoxicity indicating their usefulness for soil ureases. Structure-activity relationship studies indicate that the steric and/or electronic effects that may change the geometry of the complexes play an important role in their inhibitory potential and phytotoxicity.     

Predicting subcellular localization of multi-label proteins by incorporating the sequence features into Chou's PseAAC

The emergence of numerous genome projects has made the experimental classification of the protein localization almost impossible due to the exponential increase in the number of protein samples. However, most of the applications are merely developed for single-plex and completely ignored the presence of one protein at two or more locations in a cell. In this regard, few attempts were carried out to target Multi-label protein localizations; consequently, undesirable accuracies are achieved. This paper presents a novel approach, in which a discrete feature extraction method is fused with physicochemical properties of amino acids by using Chou's general form of Pseudo Amino Acid Composition. The technique is tested on two benchmark datasets namely: Gpos-mploc and Virus-mPLoc. The empirical results demonstrated that the proposed method yields better results via two examined classifiers i.e. ML-KNN and Rank-SVM. It is established that the proposed model has improved values in all performance measures considered for the comparison.     

Evaluating a new graphical ordinal logit method (GOLDminer) in the diagnosis of myocardial infarction utilizing clinical features and laboratory data

OBJECTIVE: We used a new graphical ordinal logit method (GOLDminer) to assess a single cardiac troponin T (cTnT) analysis at the time of admission (first generation monoclonal; Roche BMC Corp., Indianapolis, Indiana), the character of chest pain, and electrocardiographic (ECG)findings in predicting the likelihood of acute myocardial infarction (AMI) in patients presenting with suspected myocardial ischemia. The final diagnosis of AMI was based on serial ECG findings and evolution of CKMB isoenzyme levels in conjunction with clinical findings. SUBJECTS: The study population consisted of 293 consecutive patients who presented at a mean of six hours after onset of chest pain or associated symptoms warranting a "rule-out" for AMI assessment to a university-affiliated community hospital. RESULTS: The odds-ratio for an elevated cTnT (> 0. 1 ng/ml) in AMI was 22.2:1. There was an association between typical chest pain and cTnT (chi square = 78.23, p < .0001) and between abnormal ECG findings and cTnT (chi square = 108, p < .0001). The cTnT yielded diagnostic benefit in addition to chest pain characteristics and ECG findings in AMI. We present the odds-ratios for the combined features in GOLDminer plots. CONCLUSION: We demonstrate how the odds-ratios for AMI are obtained after scaling continuous to ordinal the values for a single cTnT determination alone and with other features in patients presenting with chest pain.