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To establish the use of Metaphire posthuma as a sensitive test model for ecotoxicological studies, acute toxicity testing of carbaryl, carbofuran, cypermethrin and fenvalerate on Eisenia fetida and Metaphire posthuma were carried out. Two different types of bioassays, contact filter paper toxicity and soil toxicity bioassays were used to determine LC 50 values for these insecticides. Among the tested chemicals, carbofuran was the most toxic to both the earthworm species. In paper contact method, 72 h-LC 50 values of carbofuran in M. posthuma and E. fetida were found to be 0.08 μg/cm 2 and 1.55 μg/cm 2 respectively while in soil test, 14-d LC 50 values were 0.49 mg/kg and 21.15 mg/kg respectively. On comparing the toxicity data of these chemicals for both the earthworm species, M. posthuma was found to be more sensitive than E. fetida. Based on the acute toxicity data, the order of toxicity of insecticides in both the test procedures was carbofuran>cypermethrin>carbaryl>fenvalerate for M. posthuma whereas for E. fetida it was carbofuran>carbaryl>fenvalerate>cypermethrin. Morphological changes also appeared in the organisms exposed to these chemicals which were more pronounced in M. posthuma at lower concentrations than E. fetida in both the test procedures. The results of the present study advocates the use of M. posthuma for ecotoxicity studies, being a more sensitive and reliable model than E. fetida. Based on the data on partial atomic charges, structural features and spectroscopic studies on carbaryl and carbofuran, a possible mechanism of toxicity of carbamate insecticides in earthworm was proposed.

Aims/Background: Tumor necrosis is visualized on CT scan as non enhancing hypodense area. Necrotic areas contain less oxygen and results in poor response of chemo-radiotherapy. Literature review (1) has shown that for hypodense lesions in head and neck cancer the complete response rate is lower than the isodense lesions. Locally advanced head and neck cancer require the addition of surgery but after a radical dose of radiation that is, 7000 cGy, surgery become difficult but there is no tool initially that can be used for selection of patients after delivery of 4500 cGy, that is the dose after which surgery can be performed without much difficulty. The hypothesis is that, hypodense lymph nodes even when they are small will show less response to various schedules of chemoradiotherapy so hypodensity of lymph nodes can be used as a tool to select patient, who will go for surgery after initial 4500 cGy of radiotherapy. Surgery is usually performed 2 to 3 weeks after radiotherapy, so primary can be treated to full dose while the skin in region of lymph nodes radiation field will recover from acute radiation reaction. Correlation of C T density patterns of lymph nodes in head and neck cancer patients with treatment results when two different chemoradiotherapy schedules are used is studied. Materials and Methods: Eighty three patients with locally advanced head and neck cancer were treated with two schedules of concurrent chemoradiotherapy prospectively from August 2010 to July 2011. CT Scans of the entire neck region including primary were performed. An iodine based contrast material (150 ml) was injected intravenously starting with a bolus of 50ml (3ml/s), followed by a slow (1ml/s) infusion of the remaining dose. The total tumor volume of the primary and involved neck nodes was calculated as a cuboid volume using maximum dimension in each plane: Vc= (a x b x c). Nodal density was graded. Results and Conclusion: No statistically significant association between recovery and CT density was found (X 2 = 0.306; P > 0.05).

Red spider mite, Tetranychus macfarlanei, was identified as a causative parasite for Plumbago zeylanica in India. Present study was undertaken to evaluate the detrimental role of T. macfarlanei on P. zeylanica. The relative change in biomass, stem length, stem diameter, and leaf number was significantly reduced by mite infestation as compared with uninfected plants. A significant reduction of chlorophyll a, chlorophyll b, and total chlorophyll was observed in mite-infested plants. Mite infestation significantly hampered the normal physiological process of the plant, namely, CO2 assimilation, stomatal conductance, electrolyte leakage, cell membrane injury, and carboxylation efficiency. A significant increase in tissue H2O2 and lipid peroxidation coupled with depletion of antioxidant enzymes, namely superoxide dismutase and catalase indicated augmented oxidative stress associated with biotic interaction. Finally, a significant reduction of root-specific secondary metabolite, plumbagin, production highlighte...

A pilot-scale research was conducted to study the biodegradation of trichloroethylene (TCE) in anaerobic hybrid reactor (AHR). At an influent TCE and COD concentrations of 50 and 2,000 mg/l, respectively, the AHR showed a maximum 99.93 ± 0.13 and 97.81 ± 0.42 % of TCE and COD removals, respectively, at 24 h of hydraulic retention time. The flocculent sludge ( 2 mm diameter in size) after the completion of the acclimatization study. The biomass growth yield, the maximum substrate (COD), and the maximum co-substrate (TCE) utilization rates were found to be 0.05 mg VSS/mg COD/day, 0.526 mg COD/mg VSS/day, and 0.0125 mg TCE/mg VSS/day, respectively. The AHR has the high potentiality for the treatment of high concentration of TCE present in some industrial wastewater.

We report herein the findings from a systematic study conducted on the effect of co-sensitization of two dyes i.e. N719 and rhodamine 19 perchlorate (RhCL) onto TiO2 electrodes (thickness: 4 μm), which were treated by three different carboxylic acids namely, formic acid (FA), oxalic acid (OA) and citric acid (CA). Co-sensitization was carried out by first loading the carboxylic acid treated TiO2 electrodes with RhCL dye followed by N719. The amount of dye loading was estimated from the UV/vis spectroscopy and the results show that: (i) the amount of individual dye loading (RhCL or N719) onto carboxylic acid treated TiO2 electrodes is, in general, higher than that onto untreated TiO2 electrodes; (ii) the amount of individual dye loading is highest for OA-treated and lowest for CA-treated TiO2 electrodes; and (iii) the co-sensitization leads to highest loading of N719 onto FA-treated and lowest on CA-treated TiO2 electrodes. The results of dye sensitized solar cells fabricated using these acid treated TiO2 electrodes revealed that the efficiency (η) is higher for electrodes having higher loading of N719 dye. For single N719 dye loading, the highest η of 4.5% is observed for OA-treated TiO2; while upon co-sensitization the highest η of ∼5.3% is observed for FA treated TiO2. A detailed analyses of Fourier transform infrared spectroscopy (FTIR), UV–Visible, impendence, incident photon to current efficiency (IPCE) results show that η enhancement occurs due to the following factors: (i) increased short circuit current density (JSC) owing to high N719 dye loading which enhances light harvesting; (ii) improved IPCE; (iii) increased open circuit voltage (VOC) due to an upward shift of the conduction band edge (CBE) and quasi Fermi level; and (iv) suppressed back electron transfer.

Charge transport of pure and composite thin films (20 nm thickness) of cobalt phthalocyanine (CoPc) and iron phthalocyanine (FePc) grown by molecular beam epitaxy has been investigated in the temperature range of 300 K-25 K. Composite films with optimum composition showed very high mobility of 110 cm2V-1s-1 at room temperature. X-ray diffraction and UV-Vis studies showed that the films were well oriented with planar co-facial structure. The current density-voltage (J-V) characteristics of composite films showed trap free space charge limited conduction (SCLC) while individual phthalocyanine films showed SCLC with exponential distribution of traps. Several factors such as effect of substrate, very small thickness and effect of mixing two phthalocyanines are responsible for the very high mobility observed in present study.

Hexadecafluorophthalocyanine (F16CuPc) and Cobalt phthalocyanone (CoPc) thin films of different thickness (20-200nm) have been grown by Molecular Beam Epitaxy (MBE) using different deposition rate (0.2 – 1.0 Å/s). For nanowire type growth lower deposition rate and for films of smooth surface higher deposition rate are found suitable. Charge transport (J~V) of CoPc and F16CuPc films is governed by bulk-limited processes with a bias dependent crossover from Ohmic to trap-free space-charge-limited conduction. The mobility (μ) values at 300 K were found 4.5 and 5.5 cm2 V−1 s−1 for CoPc and F16CuPc films respectively. Mechanism of reverse rectification behavior of an organic heterojunction comprising of CoPc and F16CuPc is explained by Kelvin Probe measurement.

An H 2 S sensor based on randomly distributed nano p–n junction between CuO and WO 3 has been demonstrated. Modification with CuO resulted in enhanced response kinetics towards H 2 S with high selectivity. CuO modified WO 3 thin films corresponding to 2.25 at% of Cu exhibited a sensor response of 534 in comparison to that of pure WO 3 thin films that exhibited a sensor response of 21 towards 10 ppm of H 2 S at an operating temperature of 300 °C. This enhanced response kinetics has been attributed to the formation of random nano p–n junctions distributed over the surface of the sensor film and the unique interaction of CuO with H 2 S. At elevated temperature exposure to H 2 S resulted in the conversion of CuO to CuS, which being metallic in nature causes a drastic change in the resistance of the sensor films. Formation of nano p–n junctions is supported by the increase in the sensor resistance upon CuO modification and is further corroborated by the work function studies.

Hydrothermally grown zinc oxide (ZnO) nanowires network has been modified with thin Au layer (∼10 nm) to realize an ethanol sensor. The sensor films detected ethanol with maximum response at an operating temperature of 325 °C. Incorporation of Au not only enhances the sensor response but also improves the reaction kinetics towards ethanol. The response and recovery times for Au modified sensor films towards 50 ppm of ethanol at 325 °C were 5 and 20 s, respectively. This faster reaction kinetics is attributed to the role of Au in improving the sensing properties as per the electronic sensitization mechanism and its nano-Schottky barriers type junction with ZnO. Nano-Schottky barrier type junction has been attributed further to an increase in resistance for Au modified ZnO. Work function measurements performed using Kelvin probe technique further corroborates the findings.

We have fabricated flexible field-effect transistors (FETs) using poly[N-9′-heptadecanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole)], PCDTBT, as an active channel, poly(methyl methacrylate) (PMMA) as gate dielectric and biaxially oriented polyethyleneterephthalate (BOPET) as supporting substrate. The output and transfer characteristics of the devices were measured as a function of channel length. It has been observed that various OFET parameters viz . on–off ratio (∼10 5 ), mobility ( μ ∼ 10 −4 cm 2 V −1 s −1 ), threshold voltage ( V th ∼ −14 V), switch-on voltage ( V so ∼ −6 V), subthreshold slope ( S ∼ 7 V/decade) and trap density ( N it ∼ 10 14 cm −2 V −1 ) are almost independent of the channel length, which suggested a very high uniformity of the PCDTBT active layer. These devices were highly stable under atmospheric conditions (temperature: 20–35 °C and relative humidity: 70–85%), as no change in mobility was observed on a continuous exposure for 70 days. The studies on the effect of strain on mobility revealed that devices are stable up to a compressive or tensile strain of 1.2%. These results indicate that PCDTBT is a very promising active layer for the air stable and flexible FETs.

Aims Nutritional compromise is common during high dose radiotherapy (RT) or chemoradiotherapy (CRT) for head and neck cancers. We aimed to identify the factors that determine nutritional outcome for head and neck cancer patients during radiotherapy. Methods Data from 103 patients with head and neck cancer treated with highly conformal radiotherapy to doses of 60 Gy or more in 30–33 fractions in the adjuvant or definitive setting was analyzed. All patients received complex 3D conformal radiotherapy (3DCRT) or intensity modulated radiotherapy (IMRT). Patients received regular nutritional counseling and need-based interventions. Their weight was recorded at the beginning and end of radiotherapy. Using univariate and multivariate models we tested possible predictors of weight loss of >5% and NG tube requirement. Results The mean weight loss was 3.8%. The incidence of weight loss >5% was 37.9% and NG tube placement was 24.3%. The factors significantly associated with >5% weight loss in the univariate analysis were tumor site (oro-hypopharyngeal vs. others), definitive vs. adjuvant RT; prescription dose of >60 Gy vs. 60 Gy; CRT vs. RT alone; prescription dose planning target volume (PTV) volume >235 cc and total PTV volume >615 cc. Age, sex, T stage, N stage and modality (3DCRT/IMRT) were not significant. In multivariate analysis, the total PTV volume, prescription dose PTV volume and use of chemotherapy were significant after controlling for other factors. Patients could be risk stratified based on the use of CRT and large PTV volumes. Patients with none, one or both factors had a likelihood of >5% weight loss of 0%, 30.3%, and 56.9% ( p p = 0.007). Conclusions It is possible to predict weight loss and NG tube requirements from disease and treatment related factors. PTV volumes are important predictors of nutritional compromise. Risk stratification may enable more focused counseling and identification of patients who require preventive interventions.

The Soil–Water–Atmosphere–Plant (SWAP) model was evaluated for its capability to predict groundwater table behaviour under drained conditions for a semi-arid monsoon climate in the state of Haryana (India). SWAP simulated and observed values ranging within absolute deviation of 0.17–0.18 m for groundwater table, 0.87–1.07 mm day-1 for drainage discharge rate and 7.8–39.4 mm for cumulative drain discharge. The calibrated and validated model was used to predict excess water stress utilizing the SEW30 index, which is the sum of daily exceedances (cm) of the groundwater table depth above the depth of 30 cm below the soil surface for different spacing under varying rainfall situations. The maximum annual SEW30 of 5 years having all the combinations of rainfall was 297.0 cm day with drains spaced at 75 m, 92.7 cm day with drains spaced at 50 m and 15.1 cm day for drains spaced at 25 m. These results reveal that there would be no aeration problem with drains spaced at 25 m in all the years and in years with below normal rainfall in all of the test spacing. Long-term simulations revealed that there is no residual effect of a year's rainfall pattern on the groundwater table during the next year under drained conditions. Copyright © 2013 John Wiley & Sons, Ltd.

Soil–Water–Atmosphere–Plant (SWAP) version 2.0 was evaluated for its capability to simulate crop growth and salinity profiles at Agra (India) located in a semi-arid region having deep water table and monsoon climate. The data of 12 conjunctive use treatment combinations simulating cyclic and mixing modes of fresh and saline water for wheat were used to calibrate and validate the model. Absolute deviations between the SWAP simulated and observed relative yields during calibration ranged from 2.5 to 2.9 %. A close agreement in the trend and values of measured and simulated soil salinity profiles was observed. Scenario building simulations carried out with the validated SWAP revealed that the maximum crop yields varied from 97 to 99 % with the best available water (EC 3.6 dS m−1) while the minimum ranged from 65 to 79 % in the treatment with all saline water. Other than this, the relative yield varied from 80 to 98 % in 10 other cyclic and mixing mode treatments. It was established that notwithstanding the seasonal build-up of salts due to saline water use, there would be no long-term build-up of salts as leaching during the monsoon season would render the soil profile salt free at the time of sowing of rabi (winter) crops. Thus, short-term field observations could be used in conjunction with SWAP to show that there seems to be an assured long-term sustainability when saline water is used in conjunctive mode with fresh water in monsoon climatic conditions with deep water table. These results are in conformity with the observation that many farmers in India are using saline and fresh water in conjunctive mode on a long-term basis.

Enhancement of the thermoelectric figure of merit is of prime importance for any thermoelectric material. Lead telluride has received attention as a potential thermoelectric material. In this work, the effect of Se substitution has been systematically investigated in PbTe1−xSex. The thermoelectric properties of synthesized alloys were measured in the temperature range of 300 K to 873 K. For the particular composition of x = 0.5, α was highest at ~292 μV/K, while k was lowest at ~0.75 W/m-K, resulting in the highest dimensionless figure of merit of ZT ≈ 0.95 at 600 K. The increase in thermopower for x = 0.5 can be attributed to the high distortion in the crystal lattice which leads to the formation of defect states. These defect states scatter the majority charge carriers, leading to high thermopower and high electrical resistivity. The dramatic reduction of the thermal conductivity for x = 0.5 can be attributed to phonon scattering by defect states.

Flexible polypyrrole nanosheets (thickness ∼150 nm) grown at the air–liquid interface have been investigated for charge transport and NH 3 sensing application. Polypyrrole nanosheets films exhibited a uniform and dense morphology. Temperature dependent charge transport measurements revealed that the PPy films obey Mott's 3-D variable range hopping mechanism. The mobility values calculated using temperature dependent current voltage characteristics indicated them to obey Arrhenius behaviour. These films exhibited a reversible response towards NH 3 at room temperature. The sensor exhibited a sensitivity of ∼12% with a typical response and recovery times of 240 s and 50 min, respectively towards 50 ppm of NH 3 . Raman studies indicated that there is an increase in the antisymmetrical C–N stretching upon exposure to higher concentration of NH 3 (500 ppm) and could be assigned to the interaction of NH 3 with the carbon backbone of PPy film. Our results clearly emphasize that these flexible PPy films could be used to realize flexible sensors.

Aperture of collectors in multiple Faraday Collector system is limited to typically 1 mm due to limited dispersion of ion beams of different masses and this in turn makes it difficult to achieve required peak flatness on all collectors. Further, for analysis of different elements, positions of collectors need to be mechanically adjusted from outside the vacuum system and this makes the collector system very unwieldy. To circumvent these problems, a new collector system based on variable dispersion zoom optics has been developed that facilitates fixed collector cups with wider apertures. The collector position adjustability is replaced by the variability of the dispersion using a DC quadrupole followed by deflection optics that provides matched peaks with increased peak flatness for different elements. Advantage of new optics has been demonstrated by 87 Sr/ 86 Sr isotopic ratio measurement whereby precision has been improved to 8 ppm compared to 23 ppm obtained with the conventional collector setup on the same instrument.

In this study, the anaerobic hybrid reactor (AHR) was used for the treatment of synthetic wastewater containing tetrachloroethylene (PCE) by systematic increment in the influent PCE and chemical oxygen demand (COD) concentrations. According to the acclimatization study, 99.95 ± 0.07% of PCE and 98.26 ± 0.46% of COD removals were obtained at an influent PCE and COD concentrations of 50mg/l and 2,000 mg/l, respectively. The maximum yield coefficient (Ym ) was found to be 0.055 mg biomass/mg COD, while the maximum specific substrate as COD (qm S) and co-substrate as PCE (qm CS) utilization rates were found to be 570 mg COD/g volatile suspended solids (VSS)/d and 15.83 mg PCE/g VSS/d, respectively, during the bio-kinetics study. The optimum hydraulic retention time for the maximum PCE removal was observed to be 18 h. The results of this study broadly indicated that the AHR has the high potentiality for the treatment of wastewater containing high concentration of PCE.

Understanding fission product behavior is an important aspect of nuclear safety studies. A nuclear reactor core contains complex mixture of fuel elements with different levels of enrichment, power and burnup. Conventional method of core radionuclide inventory estimation is based on use of homogenized core parameters like burnup, enrichment, specific power etc. This approach does not reveal the variation in radionuclide density among different fuel elements within the core. The present work aims to bridge this knowledge gap by estimating the distribution of radionuclides in the nuclear reactor core taking into account the heterogeneity of the core explicitly. The analysis has brought out peak radionuclide density in the core which can be helpful in appropriate estimation of the radiological release in the accidental scenarios involving failures of few fuel assemblies. A quantitative comparison of total core inventory estimated based conventional core average parameters and detailed core inventory using individual fuel assembly inventory estimate has been made.

The sources of nitrates for human can be drinking water, food, and air. After ingestion, nitrates get converted to nitrite by gastrointestinal microflora leading to methemoglobinemia and increase in free oxide radicals that predispose cells to irreversible damage. It may cause other effects such as cancer, increased infant mortality, abortions, birth defects, recurrent diarrhea, recurrent stomatitis, histopathological changes in cardiac muscles, alveoli of lungs and adrenal glands, and deterioration of immune system of the body. NOx is also toxic for human, and when inhaled, it can cause unconsciousness; vomiting; mental confusion; congestion and inflammation of respiratory tract; pulmonary edema; and genetic mutations thereby adversely affecting the development of fetus and decreasing fertility. The associations between nitrate pollution and health issues are derived from epidemiological studies (episodic, time series, crossover, and cohort), toxicological studies, and controlled human studies. Indian studies on adverse health effects of nitrate pollution are limited to only a few cross-sectional studies. Appropriate interventions at human and environmental levels may prevent humans from these toxic manifestations.

Electrodeposited CoCu/Cu multilayers were investigated by measuring both anisotropic magnetoresistance (AMR) and planar Hall effect (PHE) simultaneously. Studies have been carried out on a [Co(3 nm)/Cu(4 nm)]50 multilayer sample, where a maximum of −8.8 % GMR was observed at room temperature. A direct comparison of AMR and PHE output has been made both as a function of field and its relative orientation with respect to the current. Marked changes in PHE loops were observed at different angles (between magnetic field and applied current) whereas no noticeable changes could be found for AMR results. Such PHE outputs are the manifestations of complex spin reorganization due to strong antiferromagnetic-coupling between adjacent magnetic layers. In case of angular dependence output, when the applied field is less than the coercive field, the PHE output shows a deviation from the Sin2θ dependence that can be correlated to the domain wall propagation.

In this study NPN rf power transistors were irradiated by 175 MeV Ni 13+ ions in the dose range of 100 krad to 100 Mrad. Their characteristics such as excess base current (Δ I B = I Bpost − I Bpre ), dc current gain ( h FE ), transconductance ( g m ) and collector-saturation current ( I CSat ) were studied before and after irradiation. The damage factor ( K ) for h FE was calculated using Messenger–Spratt relation. The base current ( I B ) was found to increase significantly after irradiation and in turn decreases the h FE . The g m and collector current ( I C ) in the saturation region ( I CSat ) were found to decrease with increase in radiation dose. The results obtained here were also compared with that obtained by 140 MeV Si 10+ ions, 100 MeV F 8+ ions, 95 MeV O 7+ ions and 50 MeV Li 3+ ions irradiation studies in the same dose ranges to understand the LET effects. The recovery in the I – V characteristics of irradiated NPN transistors were studied by isothermal and isochronal annealing methods.

The objectives were to (1) quantify high temperature (HT) stress impacts at different growth stages (season long, booting to seed-set and booting to maturity) on various yield components; (2) identify the most sensitive stage(s) to short episodes of HT stress during reproductive development; (3) understand the genetic variations for HT stress tolerance based on cardinal temperatures for pollen germination; and (4) determine relative sensitivity of pollen and pistil to HT stress and associated tolerance or susceptible mechanisms in pearl millet. High temperature stress (≥36/26°C) imposed at different stages and durations caused decrease in number of seeds, individual seed weight and seed yield. Two periods (10–12 days and 2–0 days before anthesis) were identified as most sensitive to short episodes of stress, causing maximum decreases in pollen germination percentage and seeds numbers. HT stresses of ≥36/26°C results in floret sterility. Pistils were relatively more sensitive than pollen grains, causing decreased number of seeds and seed yield. HT stress increased the reactive oxygen species contents and decreased the activity of the antioxidant enzymes in both pollen and pistils. Under HT stress, pistils had relatively higher reactive oxygen species and lower antioxidant enzymes activity compared with pollen grains, which explains greater susceptibility of pistils.

Nanostructured tin oxide (SnO2) films are synthesized using physical method i.e. thermal evaporation and are further characterized with X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, and atomic force microscopy measurement techniques for confirming its structure and morphology. The chemiresistive properties of SnO2 films are studied towards different oxidizing and reducing gases where these films have demonstrated considerable selectivity towards oxidizing nitrogen dioxide (NO2) gas with a maximum response of 403% to 100ppm @200°C, and fast response and recovery times of 4s and 210s, respectively, than other test gases. In addition, SnO2 films are enabling to detect as low as 1ppm NO2 gas concentration @200°C with 23% response enhancement. Chemiresistive performances of SnO2 films are carried out in the range of 1-100ppm and reported. Finally, plausible adsorption and desorption reaction mechanism of NO2 gas molecules with SnO2 film surface has been thoroughly discussed by means of an impedance spectroscopy analysis.

In nuclear reactor containment, Sump, Calandria Vault and Calandria Vessel contain large amounts of water. Condensation on walls and containment spray system actuation also results in accumulation of water in the containment sump during the accident conditions. Evaporation of water takes place during the accident conditions and needs to be accounted in the hydrogen distribution analysis. Lump parameter codes such as ASTEC have built-in models for sump water evaporation. However, CFD codes are being increasingly used for containment hydrogen distribution studies, development of a sump water evaporation model for multi-dimensional calculations is required. The sump model is implemented through mass and energy balance using two different approaches. The main focus of the paper is on the simulation of sump evaporation experiment conducted in TOSQAN facility using the lumped parameter code and its comparison with the CFD results and the available experimental data.

The PCDTBT:PCBM solar cells were fabricated adopting a tandem layer approach to investigate the critical issues of charge trapping, radiation absorption, and efficiency in polymer solar cells. This layered structure was found to be a source of charge trapping which was identified and confirmed by impedance spectroscopy. The low efficiency in multilayered structures was related to trapping of photo-generated carriers and low carrier mobility, and thus an increased recombination. Solvent annealing of the structures in tetrahydrofuran vapors was found beneficial in homogenizing the active layer, dissolving additional interfaces, and elimination of charge traps which improved the carrier mobilities and eventually the device efficiencies.

BACKGROUND: Purpose of the study was to evaluate the efficacy of Atracurium as adjuvant with tramadol or Ketorolac in reducing the dose of lignocaine used for intravenous regional anesthesia thereby decreasing the chances of systemic toxicity of lignocaine. PATIENTS AND METHODS: Sixty adult patients of ASA grade I and II were divided into three equal groups of twenty each in randomized double blind manner. Group I patients received 40ml of 0.5% lignocaine. Group II and III received 40 ml of 0.25% lignocaine with addition of 2 mg Atracurium and 50 mg tramadol while in Group III, tramadol was replaced with 30 mg of Ketorolac. Onset of sensory and motor block, intraoperative degree of analgesia, intraoperative and postoperative complications were recorded in all the three groups. RESULTS: There was no significant difference between the groups with respect to age, weight and sex distribution. Mean time of onset of motor block in group I, II and III was 4.15+0.81, 11.7+0.86 and 14.2+0.69 minutes respectively which was statistically significant (p < 0.001). Mean time of onset of sensory block in groups I, II and III was 2.95+0.82, 8.75+1.20 and 11.05+1.04 minutes respectively which was also statistically significant. Intraoperative degree of analgesia in group II and III was comparable to group I. CONCLUSIONS: The use of 0.25% lignocaine and Atracurium with tramadol or Ketorolac provides comparable analgesia to 0.5% lignocaine used alone. This decreases the concentration and total dose of lignocaine required but delays the onset of both sensory and motor block.

SWAP (Soil-Water-Atmosphere-Plant) version 2.0 was evaluated for its capability to simulate crop growth and salinity profiles under various combinations of fresh and saline water use for irrigation at Agra (India), located in a semiarid monsoon climatic region having a deep water table. Best available water (BAW, EC 3.6 dS/m) was used for pre-sowing irrigation to wheat crop and thereafter, twelve treatment combinations were imposed with four replications to supplement missed BAW water irrigations with saline water (EC 6/8 and 12 dS/m). The model was calibrated and validated using measurements made in field trial during 2000–2003. A close agreement was observed between the measured data and simulated values. SWAP simulated and observed values for the relative yield ranged within absolute deviations of 4.2–9.7%. The validated model was later used to illustrate the consequences of long-term use of saline water on crop growth and salinity profiles. Simulated results confirmed that a yield potential exceeding 80% could be maintained by substituting saline waters up to 8 dS/m in the absence of fresh water following a pre-sowing irrigation with BAW. This strategy helps to overcome the build-up of salts particularly in years when the monsoon rainfall is below average. It could be shown and concluded that seasonal build-up of salts due to use of saline water in winter season (November–April) crops is leached during the monsoon season (June–September) when rainfall at least during the months of July and August exceeds the potential evapotranspiration. On the whole, short-term field observations could be confirmed with application of SWAP that long-term use of saline water in monsoon climate under deep water table conditions is sustainable.

In this study, anaerobic hybrid reactor (AHR) was intensively used for the treatment of synthetic wastewater containing trichloroethylene (TCE) by gradual increment in influent TCE and chemical oxygen demand (COD) concentrations. The acclimatization study revealed that 99.93 ± 0.13% and 97.81 ± 0.42% of TCE and COD could be removed at an influent TCE and COD concentrations of 50 and 2000 mg/L, respectively. The maximum yield coefficient (Ym) was found to be 0.05 mg biomass/mg COD, whereas the maximum specific substrate as COD (qm · S) and cosubstrate as TCE (qm · CS) utilization rates were found to be 0.526 mg COD/mg volatile suspended solids (VSS)/day and 0.0125 mg TCE/mg VSS/day, respectively, during the biokinetics study. An optimum hydraulic retention time for the maximum TCE removal was found to be 18 h. The AHR showed high potentiality for the treatment of wastewater containing high concentration of TCE. © 2012 American Institute of Chemical Engineers Environ Prog, 32: 1055–1060, 2013

Powdery mildew caused by Erysiphe pisi DC results heavy losses in the yield and quality of pods and seeds of pea crop. Germplasm comprising 701 accessions of garden and field pea originating from 60 countries were screened for powdery mildew resistance under natural epiphytotic conditions and 64 accessions found resistant in field screening for 2 years at one location were further screened both in field at two locations and artificially in laboratory to four isolates. The information was also obtained on the amount of genetic diversity and agronomic superiority in resistant accessions. Fifty-seven accessions showed resistant reaction for 3 consecutive years in field screening but only 14 accessions originating from 10 countries showed resistant reaction in laboratory screening against the four most prevalent isolates of E. pisi collected from different places in the area of experiment. Germplasm lines showed both complete and incomplete levels of resistance and variable reactions to different isolates. There was sufficient genetic diversity and agronomic superiority in the resistant accessions e.g. EC598655, EC598878, EC598704, IC278261, and IC218988, which may serve as useful genetic material to plant breeders for breeding pea varieties for powdery mildew resistance and high yield.

Ultrathin bi-nuclear (cobalt–iron) phthalocyanine, (Co–Fe)Pc films (thickness: ∼20 nm) were grown on (0 0 0 1) Al 2 O 3 substrates by molecular beam epitaxy. These films showed very high mobility ∼110 cm 2 V −1 s −1 at room temperature, which are nearly two orders of magnitude higher as compared to the pure CoPc and FePc films prepared under identical conditions. We demonstrated that due to high mobility of bi-nuclear phthalocyanine films, they exhibit enhanced response for chlorine (Cl 2 ) gas as compared to pure CoPc and FePc films.

Lithium borate (LBO) single crystals doped with Cu and Ag (0.25 mol% each) (Li 2 B 4 O 7 :Cu,Ag) are grown by the Czochralski method. The thermoluminescence readout on Li 2 B 4 O 7 :Cu,Ag crystals showed three glow peaks at∼375, 441 and 516 K for the heating rate of 1 K/s. The thermoluminescence sensitivity of the grown Li 2 B 4 O 7 :Cu,Ag single crystals is found to be 5 times TLD-100 and a linear dose response in the range 1 mGy to 1 kGy. The glow curve deconvolution reveals nearly first order kinetics for all the three peaks with trap depths 0.77, 1.25 and 1.34 eV respectively and corresponding frequency factors 1.6×10 9 , 1.3×10 13 and 6.8×10 11 s −1 . The continuous wave optically stimulated luminescence (CW-OSL) measurements were performed on the LBO:Cu,Ag single crystals using blue light stimulation. The traps responsible for the three thermoluminescence peaks in Li 2 B 4 O 7 :Cu,Ag are found to be OSL sensitive. The qualitative correlation between TL peaks and CW-OSL response is established. The photoluminescence studies show that in case of co-doping of Ag in LBO:Cu the emission at 370 nm in Cu states dominates over the transitions in Ag states implying doping of Ag plays a role as sensitizer when co-doped with Cu and increases overall emission.

Single crystals of CsI having different Tl concentrations have been grown by a gradient freeze technique. Carbon films were deposited on the inside surface of fused silica crucibles to avoid sticking of the grown crystals. The crystals could be extracted easily from the crucibles without involving the inversion process at higher temperatures. Effects of varying growth parameters and after-growth thermal treatment on crystal properties like daylight coloration and radiation hardness were studied. Characterization techniques including high resolution X-ray diffraction, induced absorption, photoluminescence, afterglow and thermally stimulated luminescence were employed to evaluate the grown crystals. Gamma-ray detectors were fabricated using the grown crystals that showed good linearity and nearly 7.5% resolution at 662 keV. This established a very simple and low cost method to grow small to medium size (35 mm in diameter and 25 mm in length) CsI crystals for various applications.

A methodology to estimate the conditional probability of a break in inlet feeder being the stagnation channel break in Pressurized Heavy Water Reactors is presented in this paper. According to AERB Safety Guide AERB/SG/D-5, rupture at any location of PHT system up to size of double ended largest feeder pipe belongs to category-2 events which are events of moderate frequency. For a particular range of break sizes in inlet feeder, the flow in the corresponding reactor channel reduces almost immediately to stagnant/very low flow conditions and remains sustained due to high flow inertia of PHWR pipe structure. As it is a single channel event out of hundreds of channels, the signal for reactor trip is generated very late. Consequently the fuel temperature rises sharply and fuel failure may occur. The probability of break in a feeder leading to flow stagnation conditions in the corresponding channel is low but needs to be estimated. In this paper the conditional probability of stagnation channel break for feeder pipe is estimated deterministically for a reactor similar to Indian PHWR. In this work, the stagnation channel break is identified if minimum critical heat flux ratio (MCHFR) is sustained lower than one anywhere in the corresponding reactor channel. It leads to sudden rise in fuel clad temperature due to sudden significant reduction in heat removal. There is a range of break sizes for which the clad surface temperature rises above fuel failure limits. Depending on this range and break locations in the feeder, the conditional probability is estimated. It is assumed that conditional probability depends on the range of break sizes leading to stagnation. It is observed from the calculations that the conditional probability of stagnation channel break is significant. The analysis has been carried out using thermal hydraulic code RELAP5/Mod 3.4.

Probabilistic safety assessment (PSA) is widely used for safety evaluation of Nuclear Power Plants (NPPs) worldwide. The approaches and methodologies are matured and general consensus exists on using these approaches in PSA applications. However, PSA applications for safety evaluation for non-reactor facilities are limited. Due to differences in the processes in nuclear reactor facilities and non-reactor facilities, the considerations are different in application of PSA to these facilities. The food irradiation facilities utilize gamma irradiation sources, X-ray machines and electron accelerators for the purpose of radiation processing of variety of food items. This is categorized as Non-Reactor Nuclear Facility. In this paper, the application of PSA to safety evaluation of food irradiation facility is presented considering the ‘fatality due to radiation overexposure’ as a risk measure. The results indicate that the frequency of the fatal exposure is below the numerical acceptance guidance for the risk to the individual. Further, it is found that the overall risk to the over exposure can be reduced by providing the adequate operator training and observing good safety culture.

Random networks of ZnO nanowires (ZnO-NWs) have been fabricated on the Si/SiO 2 substrates by hydrothermal process using ZnO-nanoparticles as seed. The ZnO-NWs networks have been modified by depositing ultrathin CuO layers (nominal thickness: 10 nm) using thermal evaporation of Cu followed by oxygen annealing at 600 °C. The results of photoluminescence measurements on ZnO-NWs and CuO:ZnO-NWs networks suggest formation of a p–n junction between p-CuO and n-type ZnO. The gas sensing characteristics of both ZnO-NWs and CuO:ZnO-NWs networks have been investigated. It has been demonstrated that CuO:ZnO-NWs network has selective response toward H 2 S with a sensitivity of ∼40 (for 10 ppm) at an operating temperature of 200 °C. A sensing mechanism based on the destruction of p–n junctions due to the formation of metallic CuS (product of chemical reaction between CuO and H 2 S) has been proposed.

The Millennium Development Goal 4 (MDG4) calls for the reduction in under-five mortality by two-thirds between 1990 and 2015. Only 16 of the 68 countries with 97% of the world's child deaths are on track to achieve this. This paper reviews the current evidence regarding proven interventions for reducing child mortality in high-mortality, resource-poor settings. All of these interventions require implementation within communities rather than implementation confined to only those attending health facilities with strong community participation in order to be effective. The evidence strongly suggests that facility-based interventions require a strong community-based component in order to improve child mortality in the surrounding population. We provide specific information about common community-based approaches used in the implementation of interventions with documented improvements in child mortality. A stronger emphasis on community-based approaches will be needed in order to accelerate progress in reaching MDG4. This report arises from an ongoing review of assessments of the effectiveness of community-based primary health care (CBPHC) in improving child health sponsored by the Working Group on CBPHC of the American Public Health Association.

Transport measurements on a niobium nitride (NbN) film covered with a ferromagnetic cobalt layer are reported here. The sample shows a superconducting transition (TSC) at 6.5 K. In the superconducting state, a dip in resistance is observed at a temperature referred to as TMIN. Below TMIN, resistance reappears, with a magnitude of about 1% of the normal-state resistance. The observed resistance is found to decrease on increasing the applied current (I). A possible reason for re-entrant resistance might be the vortex dynamics in NbN superconducting layer due to the stray fields created by the Co layer. Further confirmation of the observed behavior is obtained from the plot of resistance versus probe current measured at various temperatures in close vicinity of TSC.

NPN RF power transistors were irradiated with 140 MeV Si10+ ions, 100 MeV F8+ ions, 50 MeV Li3+ ions and Co-60 gamma radiation in the dose range from 100 krad to 100 Mrad. The transistor characteristics are studied before and after irradiation from which the parameters such as Gummel characteristics, excess base current (ΔIB = IBpost − IBpre), dc current gain (hFE), transconductance (gm) and collector-saturation current (ICSat) are determined. The degradation observed in the electrical characteristics is almost the same for different types of ion irradiated NPN RF power transistors with similar total doses although there is a large difference in the linear energy transfer (LET) of the ions. Further, it was observed more degradation in DC I–V characteristics of ion irradiated devices than the Co-60 gamma irradiated devices for higher doses.

Trypanosomosis which is an arthropod borne disease had become the menace to the Indian farmers because of its significant impact on the productive status of the animals. Moreover, the zoonotic effect of this disease has also proved now. Research on newer techniques for the diagnosis of this important disease has been carried out for the past hundred years, and still this search is going on for finding a more sensitive and specific test. The parasitological examination which is used for the diagnosis at the field level misses about 80% of positive cases. Keeping in view the shortcomings of the conventional diagnostic methods we carried out the present investigation for the detection of active infection of Trypanosoma evansi by monoclonal antibody based latex agglutination test (MAb-LAT). About 88 blood samples collected from cattle of the karnal district of Haryana were screened initially by Wet Blood Film (WBF) immediately after collection and their corresponding serum samples were subjected to latex agglutination test. WBF could detect the presence of motile trypanosomes only in three samples (3.41%) where as MAb-LAT detected 53 samples (60.23%) positive for the circulating antigens of Trypanosoma evansi. Study found that MAb-LAT is much sensitive than the conventional parasitological examination. Moreover, MAb-LAT is simple to perform, rapid, and cost-effective and can be used in field-level.

α-Al2O3 single crystals were irradiated to various thermal neutron fluences in the range of 1014 to 1018 n/cm2 with associated fast neutron fluence and gamma rays in the CIRUS reactor. The neutron irradiation of α-Al2O3 crystals in the reactor introduces considerable oxygen vacancies in the crystals, which is confirmed by the presence of F (203 nm) and F+ (225 and 255 nm) bands in their optical absorption (OA) spectra. The concentration of the F and F+ centers increases with the increase in neutron fluence and are responsible for the observed TL and OSL in the α-Al2O3 single crystals. The F/F+ concentration ratio of α-Al2O3 samples irradiated to thermal neutron fluence of 1018 n/cm2 (with an associated fast neutron fluence of 7 × 1015 n/cm2) is 0.68. The photoluminescence and OA studies indicate formation of excess F+ center in the neutron irradiated Al2O3 single crystals. The TL glow curve of the reactor neutron irradiated Al2O3 is different from the TL glow curve structure of the TLD-500 single crystal.

Absolute elastic differential cross sections (DCS) have been measured experimentally for several sulphur containing molecules such as SF6, CS2, DMS and DMSO using a novel high resolution electron spectrometer. The measured DCS’s were extrapolated in the forward and backward angles using a tenth order legendre polynomial based least squares fitting technique. Total cross sections (TCS) were determined by integrating the DCS over all angles for each incident energy. The influence of the sulphur atom on the molecular TCS is studied by comparing the qualitative behavior of electron impact cross sections for the sulphur containing molecules against the TCS of the sulphur atom at each incident energy. Theoretical calculations based on independent atom model are also presented as a guide to understand the nature of the electron-molecule collision processes measured in this study.

Best estimate accident analysis with uncertainty evaluation is being encouraged in the present licensing scenarios of nuclear power plants. This paper deals with uncertainty and sensitivity analysis for station blackout in PSB VVER integral test facility under the framework of coordinated research project of IAEA. Nodalization was developed using best estimate system code RELAP5/MOD3.2 and its steady state and transient level qualifications are achieved. Sampling based approaches are used to carry out uncertainty and sensitivity/importance analysis. The objective of the analysis is to get confidence for uncertainty methodology by comparing with the experimental results and extend its applicability to NPPs. Uncertainty analysis is carried out by selecting nine important input parameters with specified ranges and its uniform distributions. A design matrix of 45 × 9 is generated for variations of input parameters with the Latin Hypercube Sampling and 45 code runs were taken. Linear regression was also carried out to quantify the effect of each individual input parameter on output parameters in terms of standard rank regression coefficients. Uncertainty band in output parameters is defined between 95th and 5th percentile value. It is observed that most of the experimental values and code calculated reference values are lying within the uncertainty band. For most of the parameters, width of uncertainty band increases with transient progression time.

Photoluminescence (PL), thermoluminescence (TL) and mechanoluminescence (ML) of rare-earths (RE) doped BaSO4 and MgSO4 phosphors were studied. Undoped and doped phosphors containing different concentrations of dopant were synthesized by solid-state reaction method. X-ray diffraction (XRD) pattern of the samples matched well with their standard data of Joint Committee on Powder Diffraction’s (JCPD) file. In the PL spectrum of Dy doped samples, peaks around 470 and 580 nm were observed due to transition of Dy3+ ion. Eu doped BaSO4 showed PL peak at 380 nm due to transition of Eu2+ ion, however, in the PL spectrum of MgSO4:Eu phosphors, transition of Eu3+ was also observed along with transition of Eu2+ ion. Dy doped γ-ray-irradiated BaSO4 and MgSO4 phosphors showed at least two distinct peaks in their TL glow curves. The first peak occurred in range 120–150 °C and the second peak was observed in the range 220–230 °C. The TL glow curve of γ-ray-irradiated BaSO4:Eu contained a distinct peak at 170 °C. Two distinct peaks, one at 110 °C and another at 220 °C were observed in the TL glow curve of γ-ray-irradiated MgSO4:Eu phosphors. TL spectra showed that RE ions act as luminescence centre in BaSO4 and MgSO4 system. When the ML was excited impulsively by dropping a load on to the γ-ray-irradiated samples, only one sharp peak was observed in the ML intensity versus time curve of Dy doped samples, however, two peaks were observed in the ML intensity versus time curve of Eu doped BaSO4 and MgSO4 phosphors. The ML spectra of samples showed the characteristic emission of rare-earth impurities. Experimental results suggest that although almost similar states are responsible for PL, TL and ML, the luminescence efficiency of the phosphors depends on the mode of excitation.

We demonstrate 7-fold increase of photoluminescence efficiency in GaAs/(InAs/GaAs) quantum dot hetero-structure, employing high energy proton irradiation, without any post-annealing treatment. Protons of energy 3-5 MeV with fluence in the range (1.2-7.04) x 10(12) ions/cm(2) were used for irradiation. X-ray diffraction analysis revealed crystalline quality of the GaAs cap layer improves on proton irradiation. Photoluminescence study conducted at low temperature and low laser excitation density proved the presence of non-radiative recombination centers in the system which gets eliminated on proton irradiation. Shift in photoluminescence emission towards higher wavelength upon irradiation substantiated the reduction in strain field existed between GaAs cap layer and InAs/GaAs quantum dots. The enhancement in PL efficiency is thus attributed to the annihilation of defects/non-radiative recombination centers present in GaAs cap layer as well as in InAs/GaAs quantum dots induced by proton irradiation. (C) 2011 Elsevier Ltd. All rights reserved.

This paper presents a methodology to develop a model for disassembly of the coolant channels in Pressurized Heavy Water Reactors under severe accident conditions. This model gives criteria to decide when under severe accident condition coolant channels will rupture due to deterioration in material properties at high temperatures and increase in load due to creep sag of channels above it and hence get disassembled. Presently available severe accident codes use simplistic and optimistic criteria based on a predefined temperature to predict failure of fuel channels and an explicit criterion for disassembly of the channel is not covered. The coolant channel disassembly model developed in this paper is based on modeling the sag and pile up of channels. A uniform temperature along the length of the channel is assumed. The disassembly of the channel is assumed when the total strain at any location exceeds the failure strain for a given temperature. A 3D failure surface which is a plot of time to failure, temperature of the calandria tube and load on the calandria tubes (on account of no of channels piled up) is developed. This failure surface can be used as an input to severe accident codes to predict the progress of the core disassembly. A set of failure surfaces is recommended to be used if metal–water reaction on the outer surface is to be accounted for loss in ductility due to metal water reaction. The temperature transient of the calandria tube for a severe accident obtained from system thermal hydraulic codes can be mapped onto the failure surface. The time at which the mapped transient crosses the failure surface gives the time at which the calandria tube is disassembled. This disassembly model is an engineered model which is much more realistic as compared to the current temperature based conservative model for predicting severe accident progression.

Effect of the gate dielectric on the performance of Copper phthalocyanine (CuPc) based top contact organic field effect transistors (OFET) has been studied using thermally grown SiO2 and sputtered HfO x films with dielectric constants of 3.9 and 12.5 respectively. Operating voltages of the devices on SiO2 and HfO x were found to be 10–50 V and 2–3 V, respectively. The lower operating voltage for HfO x is attributed to the higher dielectric constant. Devices on SiO2 and HfO x were found to have field effect mobilities of 0.01 and 3.5 × 10-3 cm2/Vs and drain current modulation of 103 and 102, respectively. Scanning Electron Microscopy showed widely scattered nanowires on HfO x and densely packed nanofibers on SiO2 . X-ray diffraction studies showed better crystallinity of films on SiO2 . The results show that operating voltage of devices can be reduced by using higher dielectric constant material while mobility and FET characteristics depend on structure of CuPc that in turn is influenced by the dielectric.

Room temperature gas sensing properties of CuO nanowires synthesized by thermal oxidation of copper foils was studied in different configurations: (i) isolated nanowires aligned between two electrodes, (ii) as grown CuO foil consisting of nanowires and (iii) CuO nanowire films. Sensors were studied for response to different gases. Different sensors showed qualitatively different response on exposure to H2S . Isolated nanowires showed high sensitivity, (~200% for 10 ppm of gas) and fast response (30 s) and recovery times (60 s). In these samples, the resistance mainly decreased on exposure to H2S (though a small initial increase was observed). In CuO foils, resistance increased for low concentrations (5–10 ppm) but decreased at high concentrations. In the case of CuO nanowire films, resistance only increased on exposure of H2S (upto 400 ppm). Since CuO is a p-type semiconductor, on exposure to H2S an increase in resistance is expected due to oxygen adsorption related process. Decrease in resistance in some of the sensors was understood in terms of reaction of CuO with H2S resulting in the formation of CuS .