A combined first principles and experimental approach to Bi2WO6.

Here we synthesized Bi2WO6 (BWO) using both solid-state reaction (SBWO) and hydrothermal (HBWO-U and HBWO-S) methods. The orthorhombic Pca21 phase purity in all samples is confirmed from Rietveld refinement of X-ray diffraction data, Raman spectroscopy, and Fourier transform infrared spectroscopy. The HBWO-U and HBWO-S morphology revealed rectangular, spherical, and rod-like features with an average particle size of 55 nm in field emission scanning electron micrographs. A high-resolution transmission electron micrograph showed spherical-shaped particles in the HBWO-U sample with an average diameter of ∼10 nm. The diffuse reflectance-derived indirect electronic band gaps lie within the 2.79-3.23 eV range. The BWO electronic structure is successfully modeled by Hubbard interaction Ud and Up corrected Perdew-Burke-Ernzerhof generalized gradient approximation GGA-PBE+Ud+Up with van der Waals (vdW) force in effect. The optimized (Ud, Up) values are further justified by tuning the Hartree-Fock (HF) exact-exchange mixing parameter αHF from 25% in Heyd-Scuseria-Ernzerhof (HSE06) to 20% in the PBE-HF20% functional. Moreover, no inconsistencies were seen in the GGA-PBE+Ud+Up+vdW simulated crystallographic parameters, and the elastic tensor, phonon, and linear optical properties. Overall, the computationally cheap GGA-PBE+Ud+Up with vdW force may have successfully probed the physical properties of BWO.

Enhanced specific loss power of hematite-chitosan nanohybrid synthesized by hydrothermal method.

We used a hydrothermal technique to develop nano-scale α-Fe2O3 particles and functionalized them with chitosan. An X-ray diffraction study revealed α-Fe2O3 nanoparticles were of single-phase, lattice constants were a = 5.07 Å and c = 13.68 Å, and the grain size was 27 nm. The presence of lattice fringes in the HRTEM image confirmed the crystalline nature of the α-Fe2O3. The Mössbauer spectra reveal a mixed relaxation state, which supports the PPMS studies. Zero-field cooled studies revealed the existence of a Morin transition and blocking temperature. The z-average value of the coated particles by DLS was between 218 and 235 nm, PDI ranged from 0.048 to 0.119, and zeta potential was +46.8 mV. We incubated the Vero and HeLa cell lines for 24 h to study the viability of the nanohybrids at different concentrations. Hyperthermia studies revealed the maximum temperature and specific loss power attained by the hematite-chitosan nanohybrid solution of a concentration between 0.25-4 mg ml-1. The Tmax at the lowest and highest concentrations of 0.25 and 4 mg ml-1 were 42.9 and 48.3°C, while the SLP were 501.6 and 35.5 W g-1, which are remarkably high when the maximum magnetization of α-Fe2O3 nanoparticles was as small as 1.98 emu g-1 at 300 K.

Investigation on structure, thermodynamic and multifunctional properties of Ni-Zn-Co ferrite for Gd3+ substitution.

This study presents a modification of structure-dependent elastic, thermodynamic, magnetic, transport and magneto-dielectric properties of a Ni-Zn-Co ferrite tailored by Gd3+ substitution at the B-site replacing Fe3+ ions. The synthesized composition of Ni0.7Zn0.2Co0.1Fe2-x Gd x O4 (0 ≤ x ≤ 0.12) crystallized with a single-phase cubic spinel structure that belongs to the Fd3̄m space group. The average particle size decreases due to Gd3+ substitution at Fe3+. Raman and IR spectroscopy studies illustrate phase purity, lattice dynamics with cation disorders and thermodynamic conditions inside the studied samples at room temperature (RT = 300 K). Ferromagnetic to paramagnetic phase transition was observed in all samples where Curie temperature (T C) decreases from 731 to 711 K for Gd3+ substitution in Ni-Zn-Co ferrite. In addition, Gd3+ substitution reinforces to decrease the A-B exchange interaction. Temperature-dependent DC electrical resistivity (ρ DC) and temperature coefficient of resistance (TCR) have been surveyed with the variation of the grain size. The frequency-dependent dielectric properties and electric modulus at RT for all samples were observed from 20 Hz to 100 MHz and the conduction relaxation processes were found to spread over an extensive range of frequencies with the increase in the amount of Gd3+ in the Ni-Zn-Co ferrite. The RLC behavior separates the zone of frequencies ranging from resistive to capacitive regions in all the studied samples. Finally, the matching impedance (Z/η 0) for all samples was evaluated over an extensive range of frequencies for the possible miniaturizing application.

Synthesis and evaluation of coastal and marine biodiversity spatial information in the United Arab Emirates for ecosystem-based management.

The United Arab Emirates (UAE) host valuable coastal and marine biodiversity that is subjected to multiple pressures under extreme conditions. To mitigate impacts on marine ecosystems, the UAE protects almost 12% of its Exclusive Economic Zone. This study mapped and validated the distribution of key coastal and marine habitats, species and critical areas for their life cycle in the Gulf area of the UAE. We identified gaps in the current protection of these ecological features and assessed the quality of the data used. The overall dataset showed good data quality, but deficiencies in information for the coastline of the north-western emirates. The existing protected areas are inadequate to safeguard key ecological features such as mangroves and coastal lagoons. This study offers a solid basis to understand the spatial distribution and protection of marine biodiversity in the UAE. This information should be considered for implementing effective conservation planning and ecosystem-based management.

Capacity building of primary care physicians of the tea garden hospitals in Dibrugarh, Assam: A demonstration project.

BACKGROUND: The three most commonly occurring cancers in India are those of the breast, uterine cervix, and lip or oral cavity, together accounting for approximately 34% of all cancers. All the three cancers are amenable to prevention, early detection, and treatment through which the morbidity and mortality due to these cancers can be reduced. This pilot study was conducted to assess the operational feasibility of the national cancer screening guidelines. METHOD: This study was conducted in the Dibrugarh district of Assam in seven tea garden hospitals which serve as the primary health centers for the tea estate population in the Northeast region of India. The study intervention was a three-day training package designed to train primary care physicians in population-based screening for oral, breast, and cervical cancers. Knowledge evaluation and skill assessment were performed with a validated questionnaire and checklist, respectively. RESULTS: Pre and posttraining knowledge assessment showed significant gain in the knowledge levels of the participants in all topics. The greatest knowledge increase was seen in breast cancer (96.3%), followed by cervical cancer (57.5%), oral cancer (35.5%) and general cancer-related information (16.7%). The skill assessment done for each participant individually at the end of the training indicated a need for retraining all participants in breast cancer screening. CONCLUSION: The learnings from this study will be of great help in scaling up the capacity building programme for cancer screening when the nation-wide population-based cancer screening programme will be rolled out in the country.

Reducing chromium uptake through application of calcium and sodium in spinach.

In peri-urban areas, the use of wastewater for crop production is a common practice due to water scarcity. Moreover, in the recent years, large quantity of wastewater generation and discharge as industrial effluent in water resources is another issue for reduction of water quality. The leather industries are significantly contributing chromium (Cr) in effluent, whereas, other industries may have salt and cationic load in their discharges are mixed up. Therefore, it is mandatory to study the interactive effect of different effluent constituents on crop plants. In this connection, a pot culture experiment was conducted at the ICAR-Indian Institute of Soil Science, Bhopal to compute the effect of application of calcium (Ca) and sodium (Na) ions on Cr uptake by spinach crop in Vertisol of central India. Three levels of Cr (0, 50, 100 mg kg-1), calcium (0, 2, 4 mM), and sodium (0, 40, 80 mM) were applied in combinations. The spinach variety All Green was used as a test crop and harvested at full maturity. Results showed that application of Ca and Na reduced the Cr uptake in spinach crop. The reduction of Cr uptake was more in the root than shoot. Applied calcium acted as an essential plant nutrient and enhanced the crop biomass. Sole applications of Na adversely affected the crop biomass and Cr uptake in both root and shoot of spinach. In conclusion, application of Ca fertilizers reduced the Cr toxicity in spinach and could be used as a strategy for the safe utilization of tannery industrial effluents for crop production.

Electro-Physiology of Coupling Model and Its Impact on Naja Kaouthia Venom Treated Sciatic Nerves of Toad.

Demyelination in peripheral nerves causes dysfunction of slowing down and stoppage of nerve impulses causing many neurological diseases, such as chronic inflammatory demyelinating polyneuropathy, Guillain-Barre syndrome, etc. This paper aims to develop a recovery model having interaction of a demyelinated nerve with a normal myelinated nerve. We validated the model by coupling between peripheral nerve of toad (demyelinated with Naja kaouthia venom) and a normal nerve of toad. An increase in both nerve conduction velocity as well as compound action potential amplitude is observed in the repetition of the experiments indicating gradual recovery of the patients. The significance behind this work is to suppress the malfunctioning of the demyelinated nerve by the normal electro-physiological activity of the normal nerve for speedy recovery using coupling model. The recovery model will be used in the treatment of neurological disorders with the influence of normal neuro physiological properties of a normal adjacent nerve.

Quantifying Demyelination in NK venom treated nerve using its electric circuit model.

Reduction of myelin in peripheral nerve causes critical demyelinating diseases such as chronic inflammatory demyelinating polyneuropathy, Guillain-Barre syndrome, etc. Clinical monitoring of these diseases requires rapid and non-invasive quantification of demyelination. Here we have developed formulation of nerve conduction velocity (NCV) in terms of demyelination considering electric circuit model of a nerve having bundle of axons for its quantification from NCV measurements. This approach has been validated and demonstrated with toad nerve model treated with crude Naja kaouthia (NK) venom and also shows the effect of Phospholipase A2 and three finger neurotoxin from NK-venom on peripheral nerve. This opens future scope for non-invasive clinical measurement of demyelination.

Effect of a myosin regulatory light chain mutation K104E on actin-myosin interactions.

Familial hypertrophic cardiomyopathy (FHC) is the most common cause of sudden cardiac death in young individuals. Molecular mechanisms underlying this disorder are largely unknown; this study aims at revealing how disruptions in actin-myosin interactions can play a role in this disorder. Cross-bridge (XB) kinetics and the degree of order were examined in contracting myofibrils from the ex vivo left ventricles of transgenic (Tg) mice expressing FHC regulatory light chain (RLC) mutation K104E. Because the degree of order and the kinetics are best studied when an individual XB makes a significant contribution to the overall signal, the number of observed XBs in an ex vivo ventricle was minimized to ∼20. Autofluorescence and photobleaching were minimized by labeling the myosin lever arm with a relatively long-lived red-emitting dye containing a chromophore system encapsulated in a cyclic macromolecule. Mutated XBs were significantly better ordered during steady-state contraction and during rigor, but the mutation had no effect on the degree of order in relaxed myofibrils. The K104E mutation increased the rate of XB binding to thin filaments and the rate of execution of the power stroke. The stopped-flow experiments revealed a significantly faster observed dissociation rate in Tg-K104E vs. Tg-wild-type (WT) myosin and a smaller second-order ATP-binding rate for the K104E compared with WT myosin. Collectively, our data indicate that the mutation-induced changes in the interaction of myosin with actin during the contraction-relaxation cycle may contribute to altered contractility and the development of FHC.

Assessment of chromium efficacy on germination, root elongation, and coleoptile growth of wheat (Triticum aestivum L.) at different growth periods.

The tannery effluents contain a high concentration of chromium (Cr). It drastically reduces the crop yield when used for irrigation purpose. A huge volume of tannery effluents is available as irrigation for crop production. It is negatively affecting germination as well as yield of the crop. The wheat seeds were exposed to five different concentrations of Cr (0, 20, 40, 80, and 100 ppm). In Petri plates, 100 seeds were placed and the germination percent was recorded after 72 hour (h). Root elongation and coleoptile growth were measured at 72, 120, 168, and 240 h. Results showed that the germination percent of the test crop decreased with increasing Cr levels. It decreased by 6, 14, 30, and 37 % under the Cr concentration of 20, 40, 80, and 100 ppm, respectively. The root elongation was more sensitive than the coleoptile growth. The negative correlation was found between Cr levels and root elongation as well as coleoptile growth. These growth parameters were significantly affected up to 80 ppm of Cr level. The wheat growers using tannery effluent as irrigation should be well treated prior to application.

Comparison of different pseudotumor grading systems in a single cohort of metal-on-metal hip arthroplasty patients.

OBJECTIVE: Follow-up of pseudotumors observed with metal-artefact reducing sequence (MARS)-magnetic resonance imaging (MRI) following metal-on-metal total hip arthroplasty (MoMTHA) depends on how severe these pseudotumors are graded. Several pseudotumor grading systems for MARS-MRI have emerged but little is known of their validity. We studied the intra- and interobserver reliability of three different pseudotumor grading systems in a single cohort of MoMTHA. PATIENTS AND METHODS: Two experienced musculoskeletal radiologists independently used three different pseudotumor grading systems for classifying MARS-MRI results of the same cohort of 42 MoMTHA patients (49 hips, mean follow-up 5.2 years). Intraobserver and interobserver reliability for each grading system was measured using Cohen's kappa (κ). Variance in pseudotumor severity grading between systems was analyzed. RESULTS: Intraobserver reliability on grading pseudotumor severity with the Anderson, Matthies, and Hauptfleisch grading system scored 0.47, 0.10, and 0.35 (observer 1), and 0.75, 0.38, and 0.42 (observer 2), respectively. Interobserver reliability scores for pseudotumor severity were 0.58, 0.23, and 0.34, respectively. CONCLUSIONS: Intraobserver reliability for grading pseudotumor severity on MARS-MRI ranged from poor to good, dependent on observer and grading system used. Interobserver reliability scored best with the Anderson system. A more succinct pseudotumor severity grading system is needed for clinical use.

Objective structured practical examination in biochemistry: An experience in Medical College, Kolkata.

BACKGROUND: Undergraduate medical examination is undergoing extensive re evaluation with new core educational objectives being defined. Consequently, new exam systems have also been designed to test the objectives. Objective structured practical examination (OSPE) is one of them. OBJECTIVES: To introduce OSPE as a method of assessment of practical skills and learning and to determine student satisfaction regarding the OSPE. Furthermore, to explore the faculty perception of OSPE as a learning and assessment tool. MATERIALS AND METHODS: The first M.B.B.S students of 2011 12 batch of Medical College, Kolkata, were the subjects for the study. OSPE was organized and conducted on "Identification of Unknown Abnormal Constituents in Urine." Coefficient of reliability of questions administered was done by calculating Cronbach's alpha. A questionnaire on various components of the OSPE was administered to get the feedback. RESULTS: 16 students failed to achieve an average of 50% or above in the assessment. However, 49 students on an average achieved >75%, 52 students achieved between 65% and 75%, and 29 students scored between 50% and 65%. Cronbach's alpha of the questions administered showed to be having high internal consistency with a score of 0.80. Ninety nine percent of students believed that OSPE helps them to improve and 81% felt that this type of assessment fits in as both learning and evaluation tools. Faculty feedback reflected that such assessment tested objectivity, measured practical skills better, and eliminated examiner bias to a greater extent. CONCLUSION: OSPE tests different desired components of competence better and eliminated examiner bias. Student feedback reflects that such assessment helps them to improve as it is effective both as teaching and evaluation tools.

Aggregation of sensory data using fuzzy logic for sensory quality evaluation of food.

A method of sensory evaluation using fuzzy logic has been proposed in this paper. The method was applied for evaluation of sensory quality of tea liquor made out of dried CTC tea. Linguistic data (e.g., excellent, very good, good, satisfactory, fair, not-satisfactory, etc.) on individual tea liquor's quality attributes and the perception of the evaluators (e.g., extremely important, highly important, important, somewhat important, not-at-all important, etc.) for relative importance of these quality attributes were obtained. Sensory score between 0 and 100 for (i) Judges' preference for different quality attributes of tea liquor in general, (ii) Quality attributes ranking of tea liquor and the (ii) Overall quality of tea liquor were estimated. The last one can be utilized for the ranking of the different tea liquors.

Kruppel-like factor 2 (KLF2) regulates monocyte differentiation and functions in mBSA and IL-1ß-induced arthritis.

Kruppel-like factor 2 (KLF2) plays an important role in the regulation of a variety of immune cells, including monocytes. We have previously shown that KLF2 inhibits proinflammatory activation of monocytes. However, the role of KLF2 in arthritis is yet to be investigated. In the current study, we show that recruitment of significantly greater numbers of inflammatory subset of CD11b(+)F4/80(+)Ly6C+ monocytes to the inflammatory sites in KLF2 hemizygous mice compared to the wild type littermate controls. In parallel, inflammatory mediators, MCP-1, Cox-2 and PAI-1 were significantly up-regulated in bone marrow-derived monocytes isolated from KLF2 hemizygous mice, in comparison to wild-type controls. Methylated-BSA and IL-1ß-induced arthritis was more severe in KLF2 hemizygous mice as compared to the littermate wild type controls. Consistent with this observation, monocytes isolated from KLF2 hemizygous mice showed an increased number of cells matured and differentiated towards osteoclastic lineage, potentially contributing to the severity of cartilage and bone damage in induced arthritic mice. The severity of arthritis was associated with the higher expression of proteins such as HSP60, HSP90 and MMP13 and attenuated levels of pPTEN, p21, p38 and HSP25/27 molecules in bone marrow cells of arthritic KLF2 hemizygous mice compared to littermate wild type controls. The data provide new insights and evidences of KLF2-mediated transcriptional regulation of arthritis via modulation of monocyte differentiation and function.

Hematopoietic stem cells: transcriptional regulation, ex vivo expansion and clinical application.

Maintenance of ex vivo hematopoietic stem cells (HSC) pool and its differentiated progeny is regulated by complex network of transcriptional factors, cell cycle proteins, extracellular matrix, and their microenvironment through an orchestrated fashion. Strides have been made to understand the mechanisms regulating in vivo quiescence and proliferation of HSCs to develop strategies for ex vivo expansion. Ex vivo expansion of HSCs is important to procure sufficient number of stem cells and as easily available source for HSC transplants for patients suffering from hematological disorders and malignancies. Our lab has established a nanofiber-based ex vivo expansion strategy for HSCs, while preserving their stem cell characteristics. Ex vivo expanded cells were also found biologically functional in various disease models. However, the therapeutic potential of expanded stem cells at clinical level still needs to be verified. This review outlines transcriptional factors that regulate development of HSCs and their commitment, genes that regulate cell cycle status, studies that attempt to develop an effective and efficient protocol for ex vivo expansion of HSCs and application of HSC in various non-malignant and malignant disorders. Overall the goal of the current review is to deliver an understanding of factors that are critical in resolving the challenges that limit the expansion of HSCs in vivo and ex vivo.

Moisture sorption studies on vacuum dried coconut presscake.

Moisture sorption isotherms of vacuum dried coconut presscake were determined at 25 °C, 30 °C, and 38 °C using a gravimetric technique. Sorption isotherms exhibited Type II behaviour. The effect of temperature on equilibrium moisture content was not significant (p > 0.05). Three models available in the literature viz., GAB, BET, and Halsey models were fitted to the sorption data. Out of the three tested models, Halsey model best fitted the experimental data with a relative deviation percent below 10%. The net isosteric heat of sorption was determined from the equilibrium adsorption data using the Clausius-Clapeyron equation. Isosteric heats of sorption were found to decrease exponentially with increasing moisture content.

Evidence for pre- and post-power stroke of cross-bridges of contracting skeletal myofibrils.

We examined the orientational fluctuations of a small number of myosin molecules (approximately three) in working skeletal muscle myofibrils. Myosin light chain 1 (LC1) was labeled with a fluorescent dye and exchanged with the native LC1 of skeletal muscle myofibrils cross-linked with 1-ethyl-3-[3(dimethylamino) propyl] carbodiimide to prevent shortening. We observed a small volume within the A-band (∼10(-15) L) by confocal microscopy, and measured cyclic fluctuations in the orientation of the myosin neck (containing LC1) by recording the parallel and perpendicular components of fluorescent light emitted by the fluorescently labeled myosin LC1. Histograms of orientational fluctuations from fluorescent molecules in rigor were represented by a single Gaussian distribution. In contrast, histograms from contracting muscles were best fit by at least two Gaussians. These results provide direct evidence that cross-bridges in working skeletal muscle assume two distinct conformations, presumably corresponding to the pre- and post-power-stroke states.

Performance evaluation of a double drum dryer for potato flake production.

A double drum dryer working under atmospheric pressure was developed for water evaporation rate of 20 kg/h. Potato slurry of 12% solid concentration was dried to obtain potato flakes. Experiments were carried out at drum speed of 5 to 30 rpm, steam pressure 2 to7 kg/cm(2) gauge (saturation temperature 120-164 °C) and liquid level 5 to 10 cm at the nip of drums. The responses obtained were, moisture content of the potato flakes: 1.18-44.15% (db), dry matter output rate: 1.33-2.87 kg dry solid/h and L value of colour: 30.9-66.4. Steam pressure and drum speed were the most influencing parameters affecting all 3 responses. Optimum combination of operating variables for obtaining potato flakes of 8% (db) moisture content, high dry solid output rate and high L value of colour was: drum speed 19.6 rpm, steam pressure 4.3 kg/cm(2) gauge (saturation temperature 145 °C) and liquid level at the drum nip 6.3 cm. At this combination of independent variables, residence time of the product on drum surface would be 2 s, final moisture content of product 8% (db), product output rate 2.4 kg dry solid/h and L value of colour 53.