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The effect of climate change is being observed in India in the form of shorter winter coupled with commencement of summer quite earlier than normal. The proximity of equator and late sowing of wheat (due to late harvesting of rice) exposes the wheat crop (Triticum aestivum L.) to high temperature stress during grain filling stage leading to terminal heat stress in the crop and reduced yield. There are limited studies done till date in India to assess the long term impact of climate variability on wheat yield and to develop adaptation strategies to reduce its negative impact. Therefore, in this study, simulation model (InfoCrop) and field experiment was used to assess the impacts of terminal heat stress on growth and yield of wheat as well as to identify adaptation strategies. Simulated results showed that terminal heat stress will reduce wheat yield by 18.1%, 16.1% and 11.1%, respectively in present, 2020 and 2050 scenarios. Advancement in sowing date, application of additional dose of nitrogen and irrigation at grain filling stage were found suitable options for preventing yield loss. Among various combinations of adaptation options, early sowing by 10 days from recommended sowing date with 30 kg ha−1 additional nitrogen fertilizer and one additional irrigation at grain filling stage was found most suitable. Adaptation of these strategies will help in reducing impact of heat stress by 7.5, 6.4 and 9% respectively in present, 2020 and 2050 heat stressed scenarios.

Homocysteine is a sulfhydryl containing amino acid implicated in the pathogenesis of cardiovascular disease in multiple epidemiologic studies. However, elevated homocysteine in isolation is not known to lead to severe coronary artery disease requiring emergency intervention. We report a previously asymptomatic 55-year-old gentleman who presented with an acute myocardial infarction with bradycardia and was found to have triple-vessel coronary artery disease on angiography. After stabilization, he underwent a coronary artery bypass grafting in view of the severity of disease. A thorough evaluation revealed the absence of all traditional risk factors except elevated serum homocysteine. The evaluation of family members also revealed elevated homocysteine levels in both his sons and wife. Mutation testing of the methylenetetrahydrofolate reductase (MTHFR) gene showed homozygous Q429A mutation in the patient and heterozygous A222V and Q429A mutation in both his sons. The patient was discharged successfully and is well after 9 months of follow-up. Homocysteine has been implicated in the pathogenesis of cardiovascular disease in synergy with other traditional risk factors. This is a rare presentation of familial hyperhomocysteinemia presenting with severe coronary artery disease and elevated homocysteine levels in all family members. Elevated homocysteine levels in isolation may lead to significant cardiovascular disease and should be checked if no other risk factors are present. It may be useful to screen the patient and family members for underlying MTHFR mutations. In the absence of prospective evidence, there appears to be little harm in providing multivitamins to attempt to reduce homocysteine levels.

To see the effect of climate change on the variation of soil hydrothermal regimes and growth of maize crop, an experiment was conducted in free-air carbon dioxide enrichment (FACE) facility during the kharif season of 2015 at Climate Change Facility of Indian Agricultural Research Institute, New Delhi, India. Under elevated CO2 and ambient condition, surface bulk density (BD) were 1.38 Mgm−3 and 1.44 Mgm−3, respectively but BD were not significantly different. During different days after sowing (DAS), in 0 to 10-cm soil depth, soil water content (SWC) in FACE varied between 14.58–20.70%, whereas in ambient condition, SWC variations were in between 19.33–22.94%. In 10 to 20-cm soil depth, SWC ranged in between 20.47–27.14% in FACE and 23.57–25.42% in ambient condition for different DAS. It is also observed that the arrival of peak surface ST was 1 h early in elevated CO2 condition. Photosynthetic rate increased by 5.7% on 44 DAS and 18.1% on 70 DAS under elevated carbon dioxide condition. Elevated carbon dioxide had reduced the stomatal conductance but the reduction was not significant. Like variation in air temperature for climate change, more intensive study is required to see the effect of climate change on soil temperature and its effect on crop growth.

A glasshouse pot culture study was carried out with the aim to assess the potential toxic effects of heavy metals (Cr, Ni, Cd, Hg, and Pb) on two rice varieties (Pusa 44 and PB1509). Heavy metals get accumulated in different parts of rice plant (Oryza sativa L.) including the grains. The highest concentration of heavy metals in this study was in the roots observed rather than shoots and grains in both the rice varieties. Soil-to-grain transfer factor for non basmati rice for Ni, Pb, Cd, Cr, and Hg was 0.070, 0.028, 0.079, 0.0058, and 0.0049, respectively, and for basmati rice for Ni, Pb, Cd, Cr, and Hg was 0.065, 0.023, 0.072, 0.0050, and 0.0038, respectively. Average microbial population was more in the rhizosphere of Pusa 44 as compared to PB1509 under control condition. The viable population of bacteria, fungi, and actinomycetes was adversely affected by increasing concentration of each heavy metal. Mycorrhizal colonization was low on roots of Pusa 44 and PB1509 under metal treatments as compared to control and was minimum (22–26%) under Hg treatment.

Dietary exposure to heavy metals, namely cadmium (Cd), lead (Pb), zinc (Zn), and copper (Cu), has been identified as a risk to human health through consumption of vegetable crops. The present study investigates heavy metal contamination in irrigation water, soil, and vegetables at four peri-urban and one wholesale site in Delhi, India, and estimates the health risk index. Most of the samples collected from peri-urban areas exceeded the safe limits of lead and cadmium, whereas only lead concentration was found to be higher in vegetable samples collected from the wholesale market. Average uptake of metals by vegetables from soil decreased in the order Cd>Zn>Cu>Pb. The order of metal uptake based on transfer factor was highest in okra, cauliflower, and spinach, from greatest to least. Among the vegetables from peri-urban sites, only okra crossed the safe limit for cadmium; whereas vegetables from the wholesale site exceeded the limit for lead (potato, coriander, chilies, pea, and carrot, in order from greatest to least) with respect to health risk index.

Gram-negative plant pathogenic bacteria regulate specific gene expression in a population density-dependent manner by sensing level of Acyl-Homoserine Lactone (HSL) molecules which they produce and liberate to the environment, called Quorum Sensing (QS). The production of virulence factors (extracellular enzyme viz. cellulase, pectinase, etc.) in Pectobacterium carotovorum subsp. carotovorum (Pcc) is under strong regulation of QS. The QS signal molecule, N-(3-oxohexanoyl)-L-Homoserine Lactone (OHHL) was found as the central regulatory system for the virulence factor production in Pcc and is also under strict regulation of external environmental temperature. Under seven different incubation temperatures (24, 26, 28, 30, 33, 35, and 37 °C) in laboratory condition, highest amount of OHHL (804 violacein unit) and highest (79 %) Disease Severity Index (DSI) were measured at 33 °C. The OHHL production kinetics showed accumulation of highest concentration of OHHL at late log phase of the growth but diminution in the concentration occurred during stationary phase onwards to death phase. At higher temperature (35 and 37 °C) exposure, OHHL was not at detectable range. The effect of temperature on virulence factor production is the concomitant effect of HSL production and degradation which justifies less disease severity index in cross-inoculated tomato fruits incubated at 35 and 37 °C. The nondetection of the OHHL in the elevated temperature may because of degradation as these signal molecules are quite sensitive and prone to get degraded under different physical factors. This result provides the rationale behind the highest disease severity up to certain elevated temperature and leaves opportunities for investigation on mutation, co-evolution of superior plant pathogen with more stable HSL signals-mediated pathogenesis under global warming context.

The lattice parameter variation for phase pure cubic rocksalt (RS) Ni1-xZnxO ternary solid solutions is observed to be perfectly governed by Vegard's law. X-ray absorption near edge spectroscopy confirms the RS symmetry of Zn atoms in the cubic lattice of Ni1-xZnxO. The optical gap bowing parameter for RS Ni1-xZnxO ternary solid solutions is determined, using diffuse reflectivity, to be -0.93 ± 0.05 eV. The negative value of the bowing indicates a repulsive interaction between the ligand O-2p and the metal Ni-3d orbitals. The determined value of the bowing parameter can be useful in designing UV photodetectors based on Ni1-xZnxO solid solutions.

Sensitivity to tropospheric ozone is highly variable in cultivars of different plant species. Wheat, an important cereal crop, has been found to be sensitive to elevated ozone levels leading to differences in grain yields. The objective of this study was to compare the effects of elevated tropospheric ozone on growth, yield and nutritional quality of two species of wheat, Triticum aestivum (PBW 343) and Triticum durum (HD 2936), which are tropical wheat cultivars commonly grown in northern India. Experiments were conducted growing winter wheat (rabi season) under elevated tropospheric ozone in northern India for two years in open-top chambers (OTCs) under charcoal-filtered air (CF), non-filtered air (NF), open air (OA) and elevated ozone (EO) concentration (NF + 25-35 ppb O3). There were different species responses to EO, with the modern aestivum wheat cultivar being more sensitive than durum wheat. The declines in all growth and yield parameters were greater in T. aestivum than T. durum in both the years. On average there was a 7% greater reduction in the photosynthetic rate and stomatal conductance in T. aestivum as compared to T. durum under EO at the flowering stage, and a 6% more reduction in leaf chlorophyll was observed on T. aestivum as compared to T. durum. Exposure to elevated O3 caused a decrease in the number of leaves and leaf area index, rubisco enzyme activity and chlorophyll in both the species. More reductions in grain yield were observed in T. aestivum (15 and 19%) as compared to T. durum (9 and 13%) under EO in the two years, respectively. Filtration of air significantly increased all growth and yield parameters in both species of wheat.

Chicken infectious anaemia virus (CIAV) is an economically important pathogen affect- ing poultry industry worldwide, and renders birds susceptible to secondary infections. The present study was designed to investigate the systemic immunosuppressive effects of CIAV on T lympho- cytes bearing CD4 and CD8 receptors using flow cytometry and hematological parameters during experimental subclinical infection in chicks. Forty specific pathogen free (SPF) chicks of 6 weeks of age were randomly and equally divided into two groups. Infected group received 10 4.5 TCID 50 of CIAV while control chicks were mock inoculated. All the chicks were regularly monitored for clinical signs, hematology parameters and CD4 + and CD8 + cell populations in spleen and blood. The experimental CIAV infection was confirmed by PCR testing of the tissue samples of experimental chicks, using VP2 gene specific primers, which yielded an expected amplicon size of 651 base pairs. The analysis of the hematological parameters showed significant decline in hematocrit value (PCV), total leukocyte count (TLC) and peripheral lymphocyte count (PLC) after 15 days post infection (dpi) but with no clinical signs of CIA. Flow cytometric analysis revealed that the percentage of CD4 + CD8 - and CD4 - CD8 + T cells significantly decreased in the virus infected chicks at 15 dpi both in the spleen and blood (p

Free air carbon dioxide enrichment (FACE) facility was used to conduct the experiments during 2011-12 and 2012-13 cropping seasons for assessing the growth and yield attributes of rice (Oryza sativa L) and maize (Zea mays L). The concentration of CO2 was kept 550± 30 ppm in enriched condition. The concentration of ambient condition was 395±30. Recommended doses of NPK fertilizers were given to both the crops. Plant growth and yield parameters were measured and analyzed for both the conditions. Assessment revealed that the plant height of rice and maize did not change significantly. A significant (F= 9.800; P

An attempt has been made to study the effect of elevated temperature on soil hydrothermal regimes and winter wheat growth under simulated warming in temperature gradient tunnel (TGT). Results showed that bulk density (BDs) of 0, 0.9, and 2.5 °C were significantly different whereas BDs of 2.8 and 3.5 °C were not significantly different. Water filled pore space (WFPS) was maximum at 3.5 °C temperature rise and varied between 43.80 and 98.55%. Soil surface temperature (ST) at different dates of sowing increased with rise in sensor temperature and highest ST was observed at S5 sensors (3.5 °C temperature rise). Temperature and its difference were high for the top soil, and were stable for the deep soil. Photosynthesis rate (μmol CO2 m−2 s−1) of wheat was lower at higher temperature in different growth stages of wheat. In wheat, stomatal conductance declined from 0.67 to 0.44 mol m−2 s−1 with temperature rise. Stomatal conductance decreased with increase in soil temperature and gravimetric soil moisture content (SWC). In TGT, 0 °C temperature rise showed highest root weight density (RWD) (5.95 mg cm−3); whereas, 2.8 and 3.5 °C showed lowest RWD (4.90 mg cm−3). Harvest index was maximum (0.37) with 0 °C temperature rise, and it decreased with increase in temperature, which indicated that both grain and shoot biomass decreased with increase in temperature. Intensive studies are needed to quantify the soil hydrothermal regimes inside TGT along with the crop growth parameters.

This paper presents the biophysical impact of various interventions made under watershed development programs, in terms of the creation of additional water resources, and resultant changes in land use and cropping patterns in the Bundelkhand region of Madhya Pradesh State, India. Both primary and secondary data gathered from randomly selected watersheds and their corresponding control villages were used in this study. Analysis revealed that emphasis was given primarily to the creation of water resources potential during implementation of the programs, which led to augmentation of surface and groundwater availability for both irrigation and non-agricultural purposes. In addition, other land based interventions for soil and moisture conservation, plantation activities, and so forth, were taken up on both arable and nonarable land, which helped to improve land slope and land use, cropping pattern, agricultural productivity, and vegetation cover.

Chicken infectious anaemia virus (CIAV) is an economically important and a highly immunosuppressive virus affecting poultry industry worldwide. In this study we assessed the immunomodulatory effects of four herbal preparations namely Withania somnifera, Tinospora cordifolia, Azadirachta indica and E Care Se Herbal in resisting the viral multiplication and immunosuppression inflicted by CIAV in chicks. Day-old chicks (n = 90) were randomly and equally divided into six groups (Groups A-F). Groups A-D were administered with purified extracts of W. somnifera, T. cordifolia, A. indica and E Care Se Herbal, respectively followed by the evaluation of viral load in lymphoid organs by quantitative real-time PCR and cell mediated immune response by flow cytometric analysis of CD4+ and CD8+ T cells. Groups A-D were found to resist CIAV multiplication and pathogenesis with significant reduction of viral load compared with the infected control (P

The suitability of the second derivative method for locating component peaks in complex thermoluminescence (TL) glow curves has been investigated in this work by considering both numerically simulated and experimental TL peaks. This technique is useful to acquire knowledge of the number of component peaks in a complex TL curve which in turn serves as a basic information before applying the deconvolution technique to the glow curve. To check the consistency of the results so obtained, we have also applied the first derivative technique to TL glow curves. It is well-known that kinetic order formalism fails for saturated TL peaks with heavy retrapping. Such peaks are usually broad and, to the best of our knowledge, have not yet been observed experimentally. The present derivative technique has been used to detect whether such broad peaks are truly single or not by considering a number of numerically simulated saturated glow curves with heavy retrapping where the conventional peak shape method fails. In all the cases considered here, the second derivative technique proves to be a potential candidate for estimating the number of peaks and their respective locations in a complex TL glow curve.

Epitaxy of ZnO layers on cubic GaP(1 1 1) substrates has been demonstrated using pulsed laser deposition. Out of plane and in-plane epitaxial relationship of ZnO layer with respect to GaP substrate determined using phi (ϕ) scans in high resolution X-ray diffraction measurements are (0 0 0 1)ZnO ‖ (1 1 1)GaP and 〈 - 1 2 - 1 0 〉 ZnO ‖ - 1 1 0 GaP respectively. Our results of epitaxy of ZnO and its intense excitonic photoluminescence with very weak defect luminescence suggest that (1 1 1) oriented GaP can be a potential buffer layer choice for the integration of ZnO based optoelectronic devices on Si(1 1 1) substrates.

Crop water requirement (CWR) under the projected climate change could be mediated through changes in other weather parameters including the air temperature. The present study was directed to assess the on-farm water requirement in wheat crop in future, in semi-arid Indo-Gangetic Plains of India, through field and computer simulations. Field simulation using temperature gradient tunnels shows 18% higher crop evapotranspiration (ET c ) and 17% increase in root water extraction at 3.6 °C elevated temperature compared to 1.5 °C increase over the ambient. A time series model (ARIMA) with long-term (1984–2010) weather data of the experimental site and a global climate model (IPCC-SRES HADCM3) were used to simulate the potential ET (ET 0 ) of wheat for 2020–2021 and 2050–2051 years. The crop coefficient ( K c ) values for these years were generated through K c –CGDD (Cumulative growing-degree-days) relation by using LARS-WG model-derived daily minimum and maximum temperatures. The CWR and NIR (Net Irrigation Requirement) are likely to be less in projected years even though air temperatures increase. The CWR reduces in ARIMA outputs owing to a lower reference ET (ET 0 ) due to decline in solar radiation. Under IPCC-SRES scenarios, the ET c –crop phenophase relation [CGDD–LGP (length of growing period) response] may offset the effect of rising temperature and a net decline in CWR is observed. It may be likely that the effect of temperature increase on CWR is manifested mostly through its relation with crop phenophase (thermal requirement to complete a specific growth stage) and not the temperature effect on ET 0 per se. This is certainly a ray of hope in managing the depleting irrigation water resources in the semi-arid wheat-growing regions of the IGP.

Four field experiments, two experiments each during winter season of 2012–2013 and 2013–2014, were conducted to evaluate effect of sowing time and four wheat cultivars on population of wheat aphids. Wheat crop was found infested with Rhopalosiphum padi and Sitobion avenae in various proportions in different experiments. During vegetative crop phase, December (late) sown crop had in general higher aphid population than November (timely) sown crop, while during reproductive crop stage, timely sown crop harboured more aphids on ear heads than late planted one. October (early) and January (very late) sown crop evaded aphid attack on ear heads. Significant differences in peak aphid populations among different plantings indicated that alteration of sowing time might disturb phenological synchrony between aphids and wheat crop, affecting pest population. Aphid population was positively influenced by the temperature. Sowing dates were also found to significantly affect the crop yield. Among varieties, WR-544 was observed to have lower number of aphids than other cultivars during vegetative crop stage. Because alteration in sowing time is deemed to be one of the adaptation strategies to sustain agricultural productivity under climate change, effect of sowing time on aphid population is the need to be heeded while formulating such strategy for effective crop management.

SUMMARYA field experiment was carried out at the farm of Indian Agricultural Research Institute, New Delhi to quantify the effect of elevated carbon dioxide (CO2) and different levels of N fertiliser application on nitrous oxide (N2O) and carbon dioxide (CO2) emissions from soil under maize. The experiment included five treatments: 60 kg N ha−1under ambient CO2(385 ppm) in open plots, 120 kg N ha−1under ambient CO2(385 ppm) in open plots, 160 kg N ha−1under ambient CO2(385 ppm) in open plots, 120 kg N ha−1under ambient CO2(385 ppm) in open top chambers (OTC) and 120 kg N ha−1under elevated CO2(500 ± 50 ppm) in the OTC. Peaks of N2O flux were observed after every dose of N application. Cumulative N2O emission was 13% lower under ambient CO2as compared to the elevated CO2concentrations. There was an increase in CO2emissions with application of N from 60 kg ha−1to 160 kg ha−1. Higher yield and root biomass was observed under higher N treatment (160 kg N ha−1). There was no significant increase in maize yield under elevated CO2as compared to ambient CO2. The carbon emitted was more than the carbon fixed under elevated CO2as compared to ambient CO2levels. The carbon efficiency ratio (C fixed/C emitted) was highest in ambient CO2treatment in the OTC.

Growth in poultry sector is being challenged due to increased incidence and re-emergence of diseases caused due to evolution of several viral pathogens and use of live vaccines. Piles of economic losses are encountered due to these diseases. Avian Infectious Bronchitis (IB), caused by Corona virus, is OIE-listed disease and characterized by respiratory, renal and urogenital involvements, causing high mortality. Economic losses are encountered due to loss of productive performance of both egg and meat-type chickens. Variant viruses evolve due to spontaneous mutations and recombinations, causing disease in vaccinated flocks of all ages. Serotyping and genotyping are the common methods of classification of IBV strains. The virus has 4 clusters, grouped into 7 serotypes and the most important strains are Massachusetts, Connecticut, Arkansas, Gray, Holte and Florida along with numerous others, distributed round the globe. Several conventional and molecular diagnostic methods have been described for the diagnosis of IB in chickens. 'All-in/all-out' operations of rearing along with good biosafety measures forms the basis of prevention, whereas vaccination forms the backbone of IB control programme. Both live and inactivated (oil emulsified) conventional vaccines are available. The new generation vaccines (recombinant and vector-based) developed against locally prevailing IBV strains may be more helpful and avoid the reversion of virulence in live vaccine viruses. The present review deals with all these perspectives of this important emerging poultry pathogen.

Th e present work was carried out to investigate the correlation between viral load and the cytokine pro- fi le and virus specifi c antibody levels at fi ve day intervals up to 25 days post infection (dpi) in various tissues of chicks infected with chicken infectious anaemia virus (CIAV) at six weeks of age (sub-clinical infection). For determining the viral load in the various tissues, recombinant plasmid VP2-pET32b was prepared and serially diluted tenfold for the generation of a standard curve using real time polymerase chain reaction (PCR). Cytokine fold changes in mRNA levels of IFN-γ, IL-1, IL-2, IL-12 in the spleen and IFN-γ, IL-12 in freshly collected whole blood were determined. Th e results showed that peak viral load occurs between 10-20 days post infection in the lymphoid tissues viz., thymus, spleen, liver, bone marrow, bursa and also blood, being highest in blood followed by thymus. A varied response in the expression levels of individual cytokines was observed during all the intervals post infection. Th e IFN-γ increased two to fi ve fold in blood and spleen while IL-2 decreased in the splenic tissue during the same period. Peak IFN-γ coincided with peak viral load in the spleen at 10 dpi while in blood it peaked earlier at fi ve days post infection and remained high during the peak viral load at 10-20 dpi. Virus specifi c antibodies were signifi cantly higher at 15 dpi and were thereafter found to be strongly associated with viral load regression although higher concentrations of virus remained in the blood and thymic tissues until 25 dpi, indicating a role of other immune components in virus clearance. In conclusion, this study reports a negative correlation of viral load and the progression of the antibody response and IFN-γ cytokine expression in chicks infected with CIAV during their sub-clinical infectious stage. However, cytokine expression from the various individual immune cells like monocytes, heterophils, CD4 + T, CD8 + T cells and others during the pathogenesis of this immunosuppre ssive poultry pathogen remains to be elucidated.

Epitaxial growth of (111) oriented NiO layers on (−201) oriented β-Ga2O3 and vice versa have been carried out to obtain an all oxide p-n heterojunction (HJ) consisting of NiO/β-Ga2O3 and β-Ga2O3/NiO interfaces, respectively. Careful investigations by minimizing the effect of differential charging phenomena during x-ray photoelectron spectroscopy measurements yield a valence band offset (VBO) value of 1.6 ± 0.2 eV for both NiO/β-Ga2O3 and β-Ga2O3/NiO HJs. Thus, the VBO value is practically independent of the growth sequence for p-type NiO/n-type β-Ga2O3 HJs and follows band commutativity. The band diagram shows a staggered (type-II) band alignment and the value of the conduction band offset is found to be small (0.3 ± 0.2 eV). Our results are useful to design optoelectronic devices based on all oxide p-type NiO/n-type β-Ga2O3 HJs.

Epitaxial growth of α-Cr2O3(p-type) on c-Al2O3 and β-Ga2O3 (n-type) on α-Cr2O3(p-type) has been carried out to make an all oxide epitaxial n-type β-Ga2O3/p-type α-Cr2O3 heterojunction using RF sputtering. A valence band offset of 3.38 ± 0.2 eV at the heterojunction is determined using Kraut's method. From the bandgap measurements of α-Cr2O3 and β-Ga2O3, the conduction band offset of 1.68 ± 0.2 eV at the heterojunction is obtained. Thus, the band alignment at this heterojunction is found to be staggered (Type-II), which leads to the confinement of electrons and holes in the β-Ga2O3 layer and α-Cr2O3 layer, respectively. Our results provide a pathway to design all oxide optoelectronic devices based on a p-n heterojunction consisting of n-type β-Ga2O3 and p-type α-Cr2O3.

The investigation of devitrification in thermally annealed nanodimensional glassy alloy thin films provides a comprehensive understanding of their thermal stability, which can be used to explore potential applications. The amorphous to crystalline polymorphous transformation of cosputtered NiZr alloy (Ni78Zr22 at%) films, with a thickness lower than the reported critical limit of devitrification, was studied through detailed structural characterization and molecular dynamics (MD) simulations. Devitrification to a nanocrystalline state (Ni7Zr2 structure) was observed at 800 degC, with an increase in density (approx 3.6%) much higher than that achieved in bulk alloys. Variation in the magnetic property of the films and the overall physical structure including morphology and composition were examined before and after annealing. MD simulations were employed to effectively elucidate not only the high densification but also the increased magnetic moment after annealing, which was correlated with the simulated change in the coordination number around Ni atoms. The structural relaxation process accompanying devitrification was described as a disorder-to-order transformation while highlighting the crucial role played by chemical short range order prevalent in glassy materials.

Purpose: The study aimed to compare the effect of different materials, thicknesses, and polymerization methods and cycles, on the surface porosity of acrylic denture base resins. Materials and Methods: Conventional heat-polymerized polymethyl methacrylate (PMMA) and specially designed acrylic resin (Acron MC) were used to make 84 rectangular samples. They were divided into three groups to evaluate and compare the polymerization techniques, curing cycles, and thicknesses of the two denture base materials (28 samples each). Group A contained PMMA samples polymerized using water bath method (control group); Group B contained Acron MC samples polymerized by microwave method, and Group C contained PMMA samples polymerized by microwave method. Each group was further divided based on sample thickness and polymerization cycles. Each sample was scanned for surface porosity and area of each pore was measured using optical microscope. Data was analyzed using ANOVA, Bonferroni, and student t-tests. Unpaired student t-test was performed to compare the means of surface porosity with polymerization cycles and thicknesses among the groups. The power of study was kept at 80%. Results: Group C showed highest mean % of porosity depending on method of polymerization, different polymerization cycles (short and long) and polymerization cycles within the group. Group B showed the highest mean % of porosity depending on thickness and thickness within the groups. Conclusions: Microwavable acrylic resin polymerized by microwave energy exhibited statistically insignificant increase in porosity when compared to conventional heat cured acrylic resin by water bath method. Conventional acrylic resin polymerized by microwave energy exhibited high statistically significant porosity irrespective of sample thickness. There was statistically insignificant increase in porosity depending on sample thickness irrespective of material and method of polymerization.

In chickpea, bottlenecks associated with its domestication and low use of germplasm in improvement programs have resulted in a narrow genetic base and its vulnerability to abiotic and biotic stresses. The core and mini core collections, representing diversity in the entire collection, have been advocated for enhanced utilization of germplasm in crop improvement. A chickpea mini core (211 accessions) was evaluated for agronomic traits from 2000 and 2001 to 2003 and 2004 in post-rainy seasons under irrigated and non-irrigated conditions. The published information on the response of chickpea mini core accessions to stress revealed that 40 accessions had resistance to abiotic stress, 31 to biotic stress, and 24 had no resistance to either of the stresses. The abiotic and biotic stress resistant groups had six accessions in common. The mini core collection accessions were also a part of composite collection accessions in chickpea, which was genotyped using 48 simple sequence repeats (SSRs; BMC Plant Biol. 8:106, 2008). The agronomic evaluation, stress response, and molecular profiling data on 93 accessions, including four controls, were used to identify genetically diverse germplasm with agronomically beneficial traits. A number of genetically diverse accessions possessing agronomically beneficial traits, such as ICC 440, 637, 1098, 3325, 3362, 4872, 7441, 8621, 9586, 10399, 12307, 14402, 15680, and 15686, which meet breeders’ needs, have been identified for use in breeding and genetics to map genomic regions associated with beneficial traits and as source materials for developing high yielding and widely adapted chickpea cultivars with multiple resistance to abiotic and biotic stress.

The present study was carried out to investigate and characterize the nature of infectious bursal disease virus (IBDV) involved in the recurrent outbreaks in an experimental layer farm in Bareilly, Uttar Pradesh, India using direct tissue reverse transcription- polymerase chain reaction (RT-PCR) followed by nucleotide sequencing of VP2 gene. A total of three acute IBD outbreaks with the interval of 4-6 months were recorded in the batch of 3-5 weeks-old layer chicks in the year 2012-2013. Tissues collected from necropsied birds were found RT-PCR positive for IBDV VP2 gene. Genetic analysis of the sequenced VP2 gene revealed the IBDV belonged to very virulent (vv) subtype and had amino acids at positions 222A, 256I, 294I, and 299S typical for vvIBDV strains isolated worldwide. It had only one unique amino acid change in the antigenic peak A (210-225 aa) at position 212DàN (AspàAsn), which is not observed in any of the vvIBDVs isolated in India and abroad. Phylogenetic analysis revealed the isolates were more closely related to vvIBDV strains rA and rB (U.S.A.), Gx and HLJ-7 (China), OKYM (Japan), and shared >95% nucleotide homology with them. The VP2 gene shared 96.7% amino acid homology with IBDI+ vaccine strain used in India, comparatively higher among other vaccines strains, suggesting that IBD intermediate plus (IBDI+) vaccine might provide optimum cross protection, also for other vvIBDV strains. The vvIBDV strains remain a threat to poultry industry worldwide, and require regular monitoring and genetic analysis in order to keep track of the appearance and evolution of antigenically different IBDV strains or subtypes.

The present study was performed to evaluate the potential of four herbal preparations namely Withania somnifera, Tinospora cordifolia, Azadirachta indica and E Care Se Herbal against the haematological effects of chicken infectious anaemia virus (CIAV) in chicks and their live body weight gains. Briefly, six experimental groups (A to F), containing fifteen chicks each, were treated with herbal preparations separately from day old age. The chicks of Groups A to D were fed with W. somnifera (1% pure extract), T. cordifolia (1% pure extract), A. indica (0.2% pure extract) and E Care Se Herbal (0.1% in drinking water), respectively, while groups E and F were kept as virus positive and control group, respectively. Groups A to E were given infection with 40 times 50% chicken infectious dose (CID50) of CIAV A strain intra-muscularly on 14th day of age. Haematological parameters and body weight of the chicks of all the groups were recorded at weekly intervals for upto 10 weeks. The chicks of herbal treatment groups (A-D) showed significant improvement in their mean body weight gain and haematological indices viz., packed cell volume, haemoglobin level, total white blood cell, red blood cell and percentage lymphocyte counts, when compared with the virus infected group (E). In conclusion, the prophylactic/therapeutic application of these herbal preparations is suggested to combat depressed haematological parameters and stunted growth in chicks during CIAV infection. Further explorative studies would strengthen the potential role of herbs against this economically important avian pathogen causing huge economic losses to poultry farmers.

Chicken infectious anemia (CIA) is an economically important disease affecting poultry, especially young chicks, characterized by poor weight gain, anemia, immunosuppression and production losses. Recent reports indicate that the virus is emerging and re-emerging worldwide. Also, scarce reports regarding the molecular detection and epidemiology of virus from India are available. The aim of this study was to determine the prevalence of the virus in the commercial poultry farms of the country employing polymerase chain reaction (PCR). Out of the suspected 424 field samples tested from 12 different states of the country during the last five years (2007-2012), 311 (73.3%) samples were found positive for CIAV-DNA indicating the wide prevalence of the virus in India. The age wise prevalence of the virus indicated high prevalence in young chicks of up to three weeks (80.3%) of age compared to 3-7 (66.6%) and 7-12 (25%) week age groups. Being an immunosuppressive emerging pathogen circulating among the poultry flocks of the country, suitable prevention and control measures need to be adopted timely. This is a first elaborative report on the molecular epidemiology of CIAV in poultry flocks of the country. Extensive epidemiological studies are suggested to know the magnitude of the virus affecting poultry industry of the country, and design and formulate effective disease prevention and control strategies to reduce economic losses being caused by emerging virus. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

The multi-metallic magnetite ore at Pokhpur, Tuensang district of Nagaland is of special significance due to the presence of Ni, Cr and Co. Its smelting was carried out to selectively reduce all the oxides of nickel, chromium, cobalt and iron present in the ore into their metallic form. The reduction of chromium was found to be the controlling factor to determine the amount of reductant required to be added in the charge mix. Initially the basic laboratory scale smelting reduction study was carried out in a graphite crucible fitted in an induction furnace at two different temperatures using two reductant prior to pilot scale smelting trails in 500 kVA submerged arc furnace. The product comprising of chromium, nickel and cobalt was used to make grinding media which has been successfully tested in cement plants.

Increasing temperature is likely to affect productivity of wheat and chickpea crop. A field experiment was conducted for two consecutive years with wheat and chickpea crop raised inside the temperature gradient tunnel (TGT). Results showed that high temperature reduced crop growth duration in both the crops. Days to 50 % flowering reduced by 4–5 days in wheat with 1.8–2.9 °C increase in temperature. Photosynthesis rate, stomatal conductance and leaf area index reduced with the rise in temperature. High temperature inside the TGT caused reduction in both biomass and grain yield of wheat crop in both the years and the reductions in yield per degree temperature rise was 10.4–10.5 % in wheat crop. Number of spikes per plant, number of grains per spike, 1,000 seed weight was also affected with increased temperature. In case of chickpea crop, yield declined with the increase in temperature during the 2008–2009 year and the decline per degree temperature rise was 6.8 %. During the year 2007–2008, 1.7 °C increase in temperature showed improvement in biomass and grain yield in chickpea. Low air temperature during the crop growth period in 2007–2008 could be responsible for increased growth of chickpea under high temperature. This suggests that rise in temperature in future climatic change scenario will adversely affect wheat and chickpea crop but the response will be crop and region specific depending upon the existing climate conditions.

Field experiments were conducted in open top chamber during rabi seasons of 2009-10 and 2010-11 at the research farm of the Indian Agricultural Research Institute, New Delhi to study the effect of tropospheric ozone (O3) and carbon dioxide (CO2) interaction on yield and nutritional quality of Indian mustard (Brassica juncea (L.) Czern.). Mustard plants were grown from emergence to maturity under different treatments: charcoal-filtered air (CF, 80-85 % less O3 than ambient O3 and ambient CO2), nonfiltered air (NF, 5-10 % less O3 than ambient O3 and ambient CO2 ), nonfiltered air with elevated carbon dioxide (NF + CO2, NF air and 550 ± 50 ppm CO2), elevated ozone (EO, NF air and 25-35 ppb elevated O3), elevated ozone along with elevated carbon dioxide (EO + CO2, NF air, 25-35 ppb O3 and 550 ± 50 ppm CO2), and ambient chamber less control (AC, ambient O3 and CO2). Elevated O3 exposure led to reduced photosynthesis and leaf area index resulting in decreased seed yield of mustard. Elevated ozone significantly decreased the oil and micronutrient content in mustard. Thirteen to 17 ppm hour O3 exposure (accumulated over threshold of 40 ppm, AOT 40) reduced the oil content by 18-20 %. Elevated CO2 (500 ± 50 ppm) along with EO was able to counter the decline in oil content in the seed, and it increased by 11 to 13 % over EO alone. Elevated CO2, however, decreased protein, calcium, zinc, iron, magnesium, and sulfur content in seed as compared to the nonfiltered control, whereas removal of O3 from air in the charcoal-filtered treatment resulted in a significant increase in the same.

The purpose of this experimental study was to evaluate and record the effects of T-2 toxicity alone and in association with IBV infection on haematobiochemical parameters. A total of 128 one-week-old chicks were divided into four groups of 32 birds each and were treated respectively with T-2 toxin alone, IBV alone, T-2 toxin and co-infected with IBV, and no treatment (control) for a period of 6 weeks. Haematologically, the birds treated with T-2 toxin developed anaemia as indicated by significant decrease in haemoglobin levels, total erythrocyte counts and packed cell volume values; leucopenia, lymphocytopenia heterophilia and thrombocytopenia. The IBV infected birds exhibited lymphocytophilia and heteropoenia; the degrees of severity of leucopenia, lymphocytopenia heterophilia and thrombocytopenia were more pronounced in T-2+IBV groups. The serum biochemistry revealed hypoproteinemia and hypoalbuminemia in all the treated groups consistently. Besides, hypoglobulinemia and increased levels of alanine aminotransferase in T-2+IBV, and increased levels of alkaline phosphatase in toxin group alone were recorded. The changes in biochemical parameters were more in magnitude in the combination treatment group and their severity increased with duration of treatment. It was concluded that T-2 toxin made the birds more susceptible to IBV infection.

Increase in the concentration of atmospheric carbon dioxide (CO2) has significant impact on crop growth and productivity. A study was undertaken during the kharif season to study the impacts of elevated CO2 and cyanobacterial inoculation on growth and yield of mungbean crop under different doses of P using Free Air Carbon dioxide Enrichment (FACE) facility. The crop was grown under two CO2 levels i.e., ambient (400 µmol mol-1) and elevated (550 ± 20 µmol mol-1), with five levels of P (0, 8, 12, 16 and 20 mg P kg-1 soil) and 2 levels of calothrix sp. (with and without cyanobacteria) inoculation. Elevated CO2 level increased seed yield by 35.0% and biomass yield by 31.3%. Leaf area, photosynthesis rate and leaf chlorophyll content significantly increased at high CO2 level. Yield attributes such as number of pods plant-1, number of seeds pod-1 and test weight also increased at high CO2 level. Application of P and cyanobacterial inoculation further increased growth and yield of the crop. The study showed that application of P as well as cyanobacteria could help in improving productivity of legumes under elevated CO2 condition.

The band alignment and the quantum states of InAsxP1−x/InP surface quantum well (SQW) are investigated using ultraviolet photoelectron spectroscopy (UPS) and photoluminescence techniques. The analysis of UPS spectra of core levels In 4d, As 3d, P 3p and P 2p confirms that the top surface of InAsxP1−x/InP SQW contains an admixture of oxides, which convert into a more stable form of oxide, In(PO3)3, after optimum Ar+ ion sputtering. The values of valence band offsets between In(PO3)3/InP and InAsxP1−x/InP (x=0.57) SQW are 2.1 eV and 0.3 eV respectively, as obtained from the onsets of UPS spectra. Further, the band structure of InAsxP1−x/InP SQW is also estimated from the UPS spectra of core levels and the valence band onsets after optimum Ar+ ion sputtering. The emission of the quantum states (e1–hh1) transition blue-shifts by about 60 meV for InAs0.38P0.62/InP SQW when the top InP barrier layer thickness is decreased from 22 A to 11 A. The experimental values of e1–hh1 electronic transition in SQW match well with those of the theoretically calculated ones using a 3.6 eV potential barrier at the InP surface.

The Beta-actin gene promoter amplified by Polymerase chain reaction (PCR) technique taking genomic DNA of Seabass (Lates calcarifer) as template and the size of Seabass Beta-actin gene promoter was confirmed around 2.2 kb on Agarose gel. The amplified PCR product was ligated to linear vector pTZ57R/T (2.886 kb) and transformed into Escherichia coli DH5α cells with an efficiency of 1 × 105 transformants/μg plasmid. On cleavage with BamHI and XbaI, the desired size of insert (2.2 kb) excise out, which was further confirmed by PCR taking recombinant plasmid DNA as template. Thus, this information on Beta-actin gene promoter of Lates calcarifer is further useful to study gene expression and construction of all fish gene transfer vector to produce auto-transgenic fish for sustainable and profitable aquaculture production.

A total of 128 1-week-old chicks were classified into four groups; T-2 toxin fed (T-2), IBV infected (IBV), T-2 toxin fed and co-infected with IBV (T-2+IBV), and untreated (control) for a period of 6 weeks. Within their respective groups, the birds belonged to T-2 and T-2+IBV were exposed to 2 ppm of T-2 toxin contaminated feed for 6 weeks, and 0.2 ml of 10 EID(50) (10(5.69)/0.2 ml) inoculums of IBV isolate (India/LKW/56/IVRI/08) was used to challenge the chicks belonged to IBV alone and T-2+IBV groups after 3 weeks of the experiment. To study immunopathological effects, parameters such as lymphocyte stimulation indices (SI), haemagglutination inhibition, enzyme linked immunosorbant assay (ELISA), peripheral lymphocytes CD(4)(+) and CD(8)(+) analysis, and histopathological examination of lymphoid organs were done. Accordingly, SI values were significantly (P0.05) lower in all the treatment groups as compared to control, however, the SI values of IBV infected group were significantly higher than the values in toxin fed groups. The mean HI titres to ND vaccine was significantly (P0.05) lower in the toxin groups at all the intervals, and the antibody titres in IBV infected group were significantly (P0.05) higher than that of T-2 toxin fed and co-infected with IBV group but were significantly (P0.05) lower than the control at 21 (3) and 28 (10) days of toxin feeding (DTF) (days post infection (DPI)). Similarly, the mean IBV ELISA antibody titres in the toxin fed groups were significantly (P0.01) reduced as compared with the IBV ELISA antibody titres of IBV infected but not toxin fed group, at all intervals. Peripheral CD(4)(+):CD(8)(+) ratios in T-2+IBV group and number of CD(4)(+) and CD(8)(+) peripheral lymphocytes in all treatment groups were significantly reduced as compared to the values in control birds. However, CD(4)(+):CD(8)(+) ratios of IBV infected group at 42 (21) DTF (DPI) were found significantly (P0.05) higher than the values in control birds. Histopathologically, lymphoid organs (bursa of Fabricius, spleen, thymus, caecal tonsils and Harderian glands) showed moderate to severe necrosis (lymphocytolysis) and extensive lymphocyte depletion in all the toxin groups (T-2 and T-2+IBV groups) where the severity and extent of the lesions were more in T-2+IBV group. The findings of the present experiment revealed immunosuppressive effects of T-2 toxin and aggravated the pathology and pathogenesis of IBV infection.

The recombinant plasmid (pTK302) containing an insert of 302 bp DNA fragment of Tor khudree was isolated from recombinant clone and the size was determined. The species-specificity of the non-radioactive Digoxigenin (DIG) labeled Tor khudree specific DNA probe was also analyzed by dot-blot analysis and cross hybridization along with DNA from Tor khudree and three other Tor spp. such as Tor tor, Tor musallah and Tor putitora. Only Tor khudree showed a positive signal. The sensitivity of the assay with positive control was up to 10 pg DNA. This first study in fish deal to demonstrate the utility of non-radioactive DIG labeled technique in the development of species-specific DNA marker for identification and stock characterization of Tor khudree among the Tor spp. Thus, technique can also be applied in other genera having many species: for molecular taxonomy, stock characterization and conservation management of fish germplasm. The non-radioactive Digoxigenin (DIG) labeled Tor khudree specific DNA probe was cross hybridization along with DNA from T. khudree and three other Tor spp.; T. tor, T. musallah and T. putitora. This first study in fish demonstrate the use of DIG in the development of species-specific DNA marker for identification of T. khudree among the Tor spp. The technique can also be applied in other genera having many species for molecular taxonomical identification and thereby implifications in stock characterization and conservation management. Dot-blot hybridization specificity of Tor khudree 302 bp DNA probe with different Tor spp. (1) Control DNA (442 bp) hybridized with DIG labeled 442 bp; (2) r-plasmid (302 bp) hybridized with DIG labeled 302 bp; (3) Plain vector pTZ57R-2.886 kb hybridized with 1&2 DIG labeled probes; (4) Genomic DNA of Tor khudree hybridized with DIG labeled 302 bp probe; (5) Plain vector pTZ57R-2.886 kb hybridized with 1&2 DIG labeled probes; (6) Genomic DNA of Tor putitora hybridized with 1&2 DIG labeled probes; (7) Genomic DNA of Tor tor hybridized with 1&2 DIG labeled probes; (8) Genomic DNA of Tor musallah hybridized with 1&2 DIG labeled probes .

Physiological changes in crop plants in response to the elevated tropospheric ozone (O3) may alter N and C cycles in soil. This may also affect the atmosphere–biosphere exchange of radiatively important greenhouse gases (GHGs), e.g. methane (CH4) and nitrous oxide (N2O) from soil. A study was carried out during July to November of 2007 and 2008 in the experimental farm of Indian Agricultural Research Institute, New Delhi to assess the effects of elevated tropospheric ozone on methane and nitrous oxide emissions from rice (Oryza sativa L.) soil. Rice crop was grown in open top chambers (OTC) under elevated ozone (EO), non-filtered air (NF), charcoal filtered air (CF) and ambient air (AA). Seasonal mean concentrations of O3 were 4.3 ± 0.9, 26.2 ± 1.9, 59.1 ± 4.2 and 27.5 ± 2.3 ppb during year 2007 and 5.9 ± 1.1, 37.2 ± 2.5, 69.7 ± 3.9 and 39.2 ± 1.8 ppb during year 2008 for treatments CF, NF, EO and AA, respectively. Cumulative seasonal CH4 emission reduced by 29.7% and 40.4% under the elevated ozone (EO) compared to the non-filtered air (NF), whereas the emission increased by 21.5% and 16.7% in the charcoal filtered air (CF) in 2007 and 2008, respectively. Cumulative seasonal emission of N2O ranged from 47.8 mg m−2 in elevated ozone to 54.6 mg m−2 in charcoal filtered air in 2007 and from 46.4 to 62.1 mg m−2 in 2008. Elevated ozone reduced grain yield by 11.3% and 12.4% in 2007 and 2008, respectively. Global warming potential (GWP) per unit of rice yield was the least under elevated ozone levels. Dissolved organic C content of soil was lowest under the elevated ozone treatment. Decrease in availability of substrate i.e., dissolved organic C under elevated ozone resulted in a decline in GHG emissions. Filtration of ozone from ambient air increased grain yield and growth parameters of rice and emission of GHGs.

Plasmon peaks along with Auger P LVV peak have been observed in the ultraviolet photoelectron spectra (UPSs) of InP after 5 min of sputtering with 0.5 kV Ar + ions. Plasmon and Auger peaks are not observed in UPS of un-sputtered InP surface with native oxides of In and P. Filled electron energy levels are not observed near the Fermi level from 5 min sputtered InP surface due to increase of ionization potential of nano In clusters.

GaAs epilayers and p–i–n diodes structures grown using metal–organic vapor phase epitaxy were irradiated at room temperatures by 60 Co γ-ray radiation with varying the dose up to 50 kGy. The carrier concentration and mobility on GaAs epilayer decreases while leakage current of p–i–n diode increases at higher radiation dose (10–50 kGy). However at lower dose (

The authors report a comparative study on ex situ passivation of a near-surface GaAs0.86P0.14/Al0.6Ga0.4As quantum well using various sulfide solutions and nitrogen plasma treatments. The built-in surface electric field is changed via band bending by applying various surface passivation conditions. The band bending is measured using x-ray photoelectron spectroscopy. Reduction in surface electric field in the range of 10–35 kV/cm is observed depending on different passivation conditions. The photoreflectance spectra show enhancement in intensity and blueshift of ∼3 meV accompanied by significant reduction in the broadening parameter of the observed e1-lh1 transitions. Among all the methods studied here, passivation by Na2S⋅xH2O is found to be most effective as it removes the native oxide layer completely leading to almost flat band condition.

Objective: The objective of the study was to obtain data on prevalence and severity of dental erosion among acid industry workers in Baddi (Himachal Pradesh). Materials and Methods: A cross-sectional study was conducted among 800 battery industry workers. The demographic details were recorded on a prestructured pro forma. Type III examination was done. Dental erosion was recorded based on the index given by Bardsley (simplified scoring criteria for tooth wear index). Appropriate statistical tests were used to interpret the data. Results: The prevalence of dental erosion was found to be 48.6%. Prevalence increased with the duration of employment. Dental erosion was most commonly found in the labial surfaces of maxillary anterior teeth. Conclusion: Erosion is a condition which is multifactorial and becomes more aggravating in the presence of acidic environment. Therefore, the workers working in such conditions should be more careful, and mandatory policies should also be followed by such industries to maintain the overall health of the workers.

Lymphoid follicles in the lung parenchyma are a characteristic feature of chronic obstructive pulmonary disease (COPD). There are reports of altered CD4 T-regulatory cell numbers in COPD lungs, but the location of these cells within COPD lung tissue specific follicles has not been investigated. The presence of CD4(+)FOXP3(+) T-regulatory cells was assessed in surgically resected lung tissue from 12 COPD patients, 11 smokers with normal lung function and seven nonsmokers by combined immunofluorescence and immunohistochemistry. Organised lymphoid follicles were observed in all three groups of patients, as well as lymphoid clusters lacking organisation. The percentage of CD4 cells that were T-regulatory cells were significantly increased (p = 0.02) within COPD (16%) follicles compared with smokers (10%) and nonsmokers (8%). In contrast, there was no change (p0.05) in the percentage of T-regulatory cells in clusters or the subepithelium between groups. Lymphoid follicles in COPD patients have increased T-regulatory cells. Therefore, T-regulatory activity may be altered within COPD lymphoid follicles.

A1. High-resolution X-ray diffraction A1. Characterization A1. Defects A1. Doping A3. Metal organic vapor-phase epitaxy B2. Semiconducting III-V materials abstract A two-step growth process of gallium phosphide (GaP) epilayer on silicon substrate is carried out using metal organic vapor-phase epitaxy (MOVPE). This process includes the growth of a low-temperature GaP nucleating layer and a high-temperature GaP epilayer. In the first step, a GaP nucleating layer of thickness � 80 nm with high V/III ratio � 1725 is grown at 4251C. This is followed by the growth of a GaP layer of thickness � 760 nm with V/III ratio � 100 at 770 1C. The total thickness of the epilayer is � 845 nm as measured on a cross-section by a scanning electron microscope (SEM). A GaP layer grown by the two- step growth process shows significant improvement in morphology compared with that grown by the single-step process, as confirmed by Raman and SEM studies. High-resolution X-ray diffraction studies show that the epilayer is of single crystalline nature and structurally coherent with the silicon substrate. Epilayers grown using the two-step process show reduced dislocation density and micro-strains, with significant improvements in their structural properties. These layers also show n-type behavior with an electron density of � 8.5 � 10 17 cm � 3 , while the single-step-grown layers show p-type behavior. This change in type is explained by a reduced/increased incorporation of silicon into phosphorus/gallium sites, respectively, i.e. a predominant donor nature of silicon in GaP grown by the two-step growth process. Photoluminescence (PL), surface photovoltage spectroscopy (SPS) and transport measurements confirm a significant reduction in sub-band gap states and carrier density.