Structure of the First and Second Neighbor Shells of Water: Quantitative Relation with Translational and Orientational Order

We perform molecular dynamics simulation of water using the TIP5P model to quantify structural order in both the first shell (defined by four nearest neighbors)and second shell (defined by twelve next-nearest neighbors) of a central water molecule. We find the anomalous decrease of orientational order upon compression occurs in both shells, but the anomalous decrease of translational order upon compression occurs {\it mainly in the second shell}. The decreases of translational and orientational orders upon compression ("structural anomaly") are thus correlated only in the second shell. Our findings quantitatively confirm the qualitative idea that the thermodynamic, dynamic and structural anomalies of water are related to changes in the second shell upon compression.Comment: 12 pages, 5 figure

GBJOF: Gradient Boosting Integrated with Jaya Algorithm to Optimize the Features in Malware Analysis

Malware analysis is used to identify suspicious file transferring in the network. It can be identified efficiently by using the reverse engineering hybrid approach. Implementing a hybrid approach depends on the feature selection because the dataset contains static and dynamic parameters. The given dataset contains 85 attributes with 10 different class labels. Since it has high dimensional and multi-classification data, existing approaches of ML could be more efficient in reducing the features. The model combines the enhanced JAYA genetic algorithm with a gradient boosting technique to identify the efficiency and a smaller number of features. Many existing approaches for feature selection either implement correlation analysis or wrapper techniques. The major disadvantages of these issues are that they are facing fitting problems with a very small number of features. With the Usage of the genetic approach, this paper has achieved 95% accuracy with 12 features, approximately 7% greater than ML approaches

Environmental DNA (eDNA) metabarcoding approach in fisheries research in India

Environmental DNA (eDNA) is defined as the genetic material obtained from a water sample containing no distinguishing signs of source macroorganisms. The method utilizes DNA which is continuously excreted by organisms into the surrounding environment through mucus, gamates, faeces, blood and other cells, and captures, analyses and obtains the nucleotide sequence of this DNA based on an environmental sample. eDNA analysis has emerged as a potentially powerful tool to access aquatic community structures. Analysis of eDNA can give us information on the organisms, their abundance and biomass through two approaches – eDNA barcoding and eDNA metabarcoding. In the former, specific species are targeted in samples using standard or quantitative PCR, and using traditional Sanger sequencing method

Static and Dynamic Anomalies in a Repulsive Spherical Ramp Liquid: Theory and Simulation

We compare theoretical and simulation results for static and dynamic properties for a model of particles interacting via a spherically symmetric repulsive ramp potential. The model displays anomalies similar to those found in liquid water, namely, expansion upon cooling and an increase of diffusivity upon compression. In particular, we calculate the phase diagram from the simulation and successfully compare it with the phase diagram obtained using the Rogers-Young (RY) closure for the Ornstein-Zernike equation. Both the theoretical and the numerical calculations confirm the presence of a line of isobaric density maxima, and lines of compressibility minima and maxima. Indirect evidence of a liquid-liquid critical point is found. Dynamic properties also show anomalies. Along constant temperature paths, as the density increases, the dynamics alternates several times between slowing down and speeding up, and we associate this behavior with the progressive structuring and de-structuring of the liquid. Finally we confirm that mode coupling theory successfully predicts the non-monotonic behavior of dynamics and the presence of multiple glass phases, providing strong evidence that structure (the only input of mode coupling theory) controls dynamics.Comment: Static and Dynamic Anomalies in a Repulsive Spherical Ramp Liquid: Theory and Simulatio

Safety evaluation of chromium picolinate in experimental rats

Background: Chromium, an essential trace mineral plays an important role in the metabolism of carbohydrate, fat and proteins. Chromium picolinate (Cr.Pic) is used in alternative medicine to treat chromium deficiency. Though Cr.Pic is increasingly used to treat diabetes and obesity, studies on its safety profile is limited.Methods: Acute toxicity study was conducted by oral administration of Cr.Pic (2000 mg/kg body weight). The animals were maintained another 14 days with once a day observation. For sub-chronic studies, test groups were treated with Cr.Pic 10 mg/kg/day for 90 days. Tests for hepatic and renal function were conducted. Effect of Cr.Pic on behavioural changes and motor co-ordination was done on every week. Histopathological studies were conducted on day 90 at the end of the experiment.Results: Acute toxicity study of Cr.Pic showed no signs of toxicity and mortality. Absence of any behavioural alteration or mortality during the period of 14 days indicates that Cr.Pic has no latent effect. Similar results were obtained with sub-chronic studies suggesting safety of Cr.Pic. Cr.Pic treated groups showed no changes in learning and motor co-ordination compared to the untreated group. No gross histopathological changes were seen in any group indicating safety of Cr.Pic.Conclusions: The present study conferred safety profile of Cr.Pic from normal results obtained in hepatic function, renal function, behavioural and histopathological studies, suggesting its safety

Glass transition in biomolecules and the liquid-liquid critical point of water

Using molecular dynamics simulations, we investigate the relation between the dynamic transitions of biomolecules (lysozyme and DNA) and the dynamic and thermodynamic properties of hydration water. We find that the dynamic transition of the macromolecules, sometimes called a ``protein glass transition'', occurs at the temperature of dynamic crossover in the diffusivity of hydration water, and also coincides with the maxima of the isobaric specific heat $C_P$ and the temperature derivative of the orientational order parameter. We relate these findings to the hypothesis of a liquid-liquid critical point in water. Our simulations are consistent with the possibility that the protein glass transition results from crossing the Widom line, which is defined as the locus of correlation length maxima emanating from the hypothesized second critical point of water.Comment: 10 Pages, 12 figure

Isolation and Characterization of Pathogenic Vibrio Alginolyticus from Sea Cage Cultured Cobia (Rachycentron Canadum (Linnaeus 1766)) in India

The epizootics of vibriosis caused serious economic losses to farmers. Natural blooms of the pathogen can be prevented by sea cage management measures such as, changing the inner net of the cages, changing the location of the cages to relatively clean water (about 50 m apart) from the affected site and providing shade over the cages while the water temperature rises. Supplementation of the feed with immunostimulants and mineral mixture may be practised to improve the immune response against infection. Early diagnosis and sea cage management measures may prevent occurrences of the infection

Visible fluorescence induced by the metal semiconductor transition in composites of carbon nanotubes with noble metal nanoparticles

We show that single-walled carbon nanotube (SWNT) bundles emit visible fluorescence in the presence of noble metal nanoparticles and nanorods in the solid state. Conductivity measurements with metallic nanotubes, isolated from pristine SWNTs, show that they become semiconducting in the presence of the metal nanoparticles. Nanoparticle binding increases the defects in the nanotube structures which is evident in the Raman spectra. The metal-semiconductor transition removes the nonradiative decay channels of the excited states enabling visible fluorescence. Nanotube structures are imaged using this emission with resolution below the classical limits

Temperature-dependent Raman study of CeFeAsO0.9F0.1 Superconductor: Crystal field excitations, phonons and their coupling

We report temperature-dependent Raman spectra of CeFeAsO0.9F0.1 from 4 K to 300 K in spectral range of 60 to 1800 cm-1 and interpret them using estimates of phonon frequencies obtained from first-principles density functional calculations. We find evidence for a strong coupling between the phonons and crystal field excitations; in particular Ce3+ crystal field excitation at 432 cm-1 couples strongly with Eg oxygen vibration at 389 cm-1 . Below the superconducting transition temperature, the phonon mode near 280 cm-1 shows softening, signaling its coupling with the superconducting gap. The ratio of the superconducting gap to Tc thus estimated to be ~ 10 suggests CeFeAsO0.9F0.1 as a strong coupling superconductor. In addition, two high frequency modes observed at 1342 cm-1 and 1600 cm-

Thermodynamics, Structure, and Dynamics of Water Confined between Hydrophobic Plates

We perform molecular dynamics simulations of 512 water-like molecules that interact via the TIP5P potential and are confined between two smooth hydrophobic plates that are separated by 1.10 nm. We find that the anomalous thermodynamic properties of water are shifted to lower temperatures relative to the bulk by $\approx 40$ K. The dynamics and structure of the confined water resemble bulk water at higher temperatures, consistent with the shift of thermodynamic anomalies to lower temperature. Due to this $T$ shift, our confined water simulations (down to $T = 220$ K) do not reach sufficiently low temperature to observe a liquid-liquid phase transition found for bulk water at $T\approx 215$ K using the TIP5P potential. We find that the different crystalline structures that can form for two different separations of the plates, 0.7 nm and 1.10 nm, have no counterparts in the bulk system, and discuss the relevance to experiments on confined water.Comment: 31 pages, 14 figure