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Terminal heat stress leads to sizeable yield loss in late-sown wheat in tropical environments. Several synthetic compounds are known to counteract plant stress emanating from abiotic factors. A field experiment was conducted in Sabour (eastern India) during 2013–2016 to investigate the field efficacy of two synthetic compounds, calcium chloride (CaCl2) and arginine, for improving grain yield of two contrasting wheat cultivars (DBW 14 and K 307) facing terminal heat stress. For this, foliar spray of 18.0 mM CaCl2 at booting (CCB) or anthesis (CCA), 9.0 mM CaCl2 at both booting and anthesis (CCB+A), 2.5 mM arginine at booting (ARGB) or anthesis (ARGA) and 1.25 mM arginine at both booting and anthesis (ARGB+A) treatments along with no-spray and water-spray treatments were evaluated in late-sown wheat. The highest grain yield was recorded in treatment CCB+A, followed by CCA and ARGB+A. However, the effect of these compounds was marginal on grain yield when applied only at the booting stage. Grains/ear and thousand-grain weight were found to be the critical determinants for yield in late-sown wheat. During the anthesis to grain filling period, flag-leaf chlorophyll degradation and increase in relative permeability in no-spray treatment were 34–36% and 29–52%, respectively, but these values were reduced considerably in CCB+A treatment followed CCA. Thus, foliar spray of 9.0 mM CaCl2 both at booting and anthesis stages may be recommended for alleviating the negative impacts of terminal heat stress in late-sown wheat and improving its productivity (>13%).
In recent years, the government of Bangladesh has encouraged private sector involvement in producing mid-level health cadres including Medical Assistants (MAs). The number of MAs produced has increased significantly. We assessed students’ characteristics, educational services, competencies and perceived attitudes towards health service delivery in rural areas.
We used a mixed method approach using quantitative (questionnaire survey) and qualitative (key informant interviews and roundtable discussion) methods. Altogether, five public schools with 238 students and 30 private schools with 732 students were included. Statistical analyses were performed using STATA v-12. Qualitative data were analyzed thematically.
The majority of the students in both public (66%) and private medical assistant training schools (MATS) (61%) were from rural backgrounds. They spent the majority of their time in classroom learning (public 45% versus private 42%) and the written essay exam was the common form of a students’ performance assessment. Compared with students of public MATS, students of private MATS were more confident in different aspects of educational areas, including managing emerging health needs (P<0.001); evidence-based practice (P=0.002); critical thinking and problem solving (P=0.02), and use of IT/computer skills (P<0.001). Students were aware of not having adequate facilities in rural areas (public 71%, private 65%), but they perceived working in rural areas will offer several benefits, including use of learnt skills; friendly rural people; and opportunities for real-life problem solving, etc.
This study provides a current picture of MATS students’ characteristics, educational services, competencies and perception towards working in rural areas. The MA students in both private and public sectors showed a greater level of willingness to serve in rural health facilities. The results are promising to improve health service delivery, particularly in rural and hard-to-reach areas of Bangladesh.
In most mental illnesses, onset occurs before the age of 25 and the earliest stages are critical. The youth bear a large share of the burden of disease associated with mental illnesses. Yet, Canadian youths with mental health difficulties face delayed detection; long waiting lists; inaccessible, unengaging services; abrupt transitions between services; and, especially in remoter regions, even a complete lack of services. Responding to this crisis, the Canadian Institutes of Health Research announced a 5-year grant that was awarded to ACCESS, a pan-Canadian network of youths, families, clinicians, researchers, policymakers, community organisations and Indigenous communities. Using strategies developed collaboratively by all stakeholders, ACCESS will execute a youth mental healthcare transformation via early detection, rapid access and appropriate, high-quality care. The project includes an innovative, mixed-methods service research component. Similar in many respects to other national youth mental health initiatives, ACCESS also exhibits important differences of scale, scope and approach.
Large areas of rainfed lowlands of Asia annually experienced flash flooding during the rice-growing season, which is an important abiotic stress that adversely affect grain yield of rice (Oryza sativa L.) crop. Submergence stress is a common environmental challenge for agriculture sustainability in these areas because lack of high-yielding, flood-tolerant cultivars. In this study, IR64-Sub1 and IR64 were compared for their tolerance to submergence at active tillering (AT), panicle initiation (PI) and heading (H) stages with nitrogen and phosphorus application time. We evaluated the role of cultivars, stage of submergence and N and P application on phenology, leaf senescence (LS), photosynthetic (Pn) rate, yield attributes and yield. Under non-submerged conditions, no difference was observed in phenology, Pn rate and yield of both cultivars. Submergence substantially reduced biomass, Pn rate, yields attributes and yield across cultivars with more drastic reduction in IR64. Submergence at H stage proves to be most detrimental. Nitrogen application after desubmergence with basal P improved the Pn rate resulting in significantly higher yield and yield components. Nitrogen application before submergence resulted in increased LS and ethylene accumulation in shoots leading to drastic reduction in growth, Pn rate and yield. Crop establishment and productivity could therefore be enhanced in areas where untimely flooding is anticipated by avoiding N application before submergence and applying N after desubmergence with basal P (phosphorus).
Electrochemical performance of hybrid supercapacitor (HSC) utilizing surface sculpted Li4Ti5O12 (LTO) insertion electrode having nanoplatelet-like morphology and activated carbon (AC) electrode is investigated for energy storage application. Cyclic voltammetry (CV) at variable scan rates 0.5 to 60 mV.s-1 in the 0-3.2 V range show pseusocapacitive behavior and fast rate of current change indicating rapid Faradaic kinetics. Nyquist impedance study show charge transfer resistance due to kinetic effects of electron transfer and Li+ de-intercalation process at the LTO anode. Low capacity (0.2 C-1C) charge-discharge (CD) curves show high Coulomb efficiency with marginal reduction at high 5-10 C rates due to irreversibility of adsorbed PF6 anions at the electrolyte-AC interface. Galvanostatic CD cycling tests over 50 cycles at different C-rates show decline in storage capacity due to electrode polarization effects. Reduction, broadening and shift of the Raman line at 678 cm-1 from Ti-O bonds in TiO6 octahedra after cycling indicates Li insertion reactions in functioning of hybrid supercapacitor. The hybrid supercapacitor cells have shown energy density, 29 Wh.kg-1 and power density, 350 W.kg-1.
Here we discuss proteomic analyses of whole cell preparations of the mosquito stages of malaria parasite development (i.e. gametocytes, microgamete, ookinete, oocyst and sporozoite) of Plasmodium berghei. We also include critiques of the proteomes of two cell fractions from the purified ookinete, namely the micronemes and cell surface. Whereas we summarise key biological interpretations of the data, we also try to identify key methodological constraints we have met, only some of which we were able to resolve. Recognising the need to translate the potential of current genome sequencing into functional understanding, we report our efforts to develop more powerful combinations of methods for the in silico prediction of protein function and location. We have applied this analysis to the proteome of the male gamete, a cell whose very simple structural organisation facilitated interpretation of data. Some of the in silico predictions made have now been supported by ongoing protein tagging and genetic knockout studies. We hope this discussion may assist future studies.
This study describes the epidemiology of human salmonellosis in New Zealand using notified, hospitalized and fatal cases over a 12-year period (1997–2008). The average annual incidence for notifications was 42·8/100 000 population and 3·6/100 000 population for hospitalizations. Incidence was about twice as high in summer as in winter. Rural areas had higher rates than urban areas (rate ratio 1·23, 95% confidence interval 1·22–1·24 for notifications) and a distinct spring peak. Incidence was highest in the 0–4 years age group (154·2 notifications/100 000 and 11·3 hospitalizations/100 000). Hospitalizations showed higher rates for Māori and Pacific Island populations compared to Europeans, and those living in more deprived areas, whereas notifications showed the reverse, implying that notifications are influenced by health-seeking behaviours. Salmonella Typhimurium was the dominant serotype followed by S. Enteritidis. For a developed country, salmonellosis rates in New Zealand have remained consistently high suggesting more work is needed to investigate, control and prevent this disease.
To describe the syndrome of optic nerve involvement in cases of allergic fungal sinusitis.
Academic tertiary care centre.
Analysis of prospectively accrued data for 10 consecutive cases (three bilateral, giving 13 eyes) with visual loss secondary to optic nerve compression, from a total of 70 cases of allergic fungal sinusitis undergoing surgical treatment between June 1997 and May 2007.
The mean duration of rhinological symptoms prior to the onset of visual loss was 22 months. At presentation, visual loss ranged from a visual acuity of 6/12 to complete loss of light perception. Bilateral involvement was noted in three of the 10 cases. Urgent surgical decompression with removal of all fungal debris and decompression of the optic nerve resulted in visual recovery in seven of the 13 eyes. On univariate analysis, recovery was less likely in cases with long standing visual loss, and in cases with complete visual loss.
Long standing allergic fungal sinusitis may be complicated by visual loss due to compression of the optic nerve. Urgent surgery to clear the sinuses and decompress the optic nerve is successful in reversing visual loss in cases with partial visual loss.
The evolution of stress during the MOCVD growth of AlN thin films on sapphire substrates under both low and high temperature conditions has been evaluated. The final stress state of the films is assumed to consist of the summation of stresses from three different sources: (1) the stress which arises from residual lattice mismatch between film and substrate i.e. that which persists after partial relaxation by misfit dislocation formation. The extent of relaxation is determined from High Resolution TEM analysis of the substrate/film interface; (2) the stress arising from the coalescence of the 3D islands nucleated in this high mismatch epitaxy process. This requires knowledge of the island sizes just prior to coalescence and this was provided by AFM studies of samples grown under the conditions of interest; and (3) the stress generated during post-growth cooling which arises from the differences in thermal expansion coefficient between AlN and sapphire. The final resultant stress, comprising the summation of stresses arising from these three sources, is found to be tensile in the sample grown at lower temperature and compressive in the sample grown at higher temperature. These results are in general qualitative agreement with results of TEM and High resolution X-ray diffraction (HRXRD) studies, which show evidence for tensile and compressive stresses in the low temperature and high temperature cases, respectively.
The dynamics of surface fluctuations in thin supported polystyrene films have been investigated using x-ray photon correlation spectroscopy (XPCS) in reflection geometry. The results from the films thicker than four times of the radius of gyration (Rg) of polystyrene show the behavior of the capillary waves expected in viscous liquid. However, thinner films show a deviation indicating the need to account for viscoelasticity. Theoretical considerations with viscoelastic liquid model has been performed by introducing frequency dependent viscosity and compared with Fredrickson’s brush model (Macromolecules, 25, 2882 (1992)). The theory has been extended to the surface and interfacial modes in a bilayer film system. The results will be discussed in terms of surface tension, viscosity, and shear modulus.
The residual effects of subsoil compaction (below 0.15 m depth) on soil properties, growth, yields and nutrient uptake by irrigated wheat (Triticum aestivum) and cotton (Gossipium hirsutum) are reported. The study was initiated during 1997 on a sandy clay loam soil in a semiarid region of Pakistan. Results showed that the adverse effects of subsoil compaction on bulk density, penetration resistance, total porosity and air-filled porosity of soil persisted for at least four years. In the third and fourth years after the imposition of treatments, compaction decreased yields of wheat by 12–18% and by 7% for cotton. The corresponding reductions in nutrient uptake by wheat were 11–16% for N, 11–15% for P and 5–10% for K. For cotton, the values were 9% for N, 3% for P and 7% for K. Subsoil compaction decreased nutrient use efficiency by 16% in wheat and 5% in cotton. The reductions in water use efficiency were estimated to be 11% in wheat and 7% in cotton. Wheat root length density was also decreased in the subsoil.
Scheelite mineralization in the granulite-facies supracrustal sequences of the Kerala Khondalite Belt, southern India is reported. The supracrustal sequences where the mineralization is found comprise granulite-grade metasediments which underwent metamorphism at ∼550 Ma. The mineralization is assumed to have formed by late-stage metasomatism that overprinted the regional metamorphism of the country rock (garnet-biotite gneiss) and occurs along a quartz vein that intrudes the regional foliation. The paragenetic data from the vein demonstrate unambiguously a separate cycle of hydrothermal activity, resulting in metasomatism and mineralization. Scheelite is found in both the altered host rock along the foliation plane and in the quartz vein. Fluid inclusions preserved in the vein suggest that the mineralizing fluids were saline-aqueous in composition, while those in the country rocks were predominantly CO2-rich. The mineral chemistry and bulk-rock chemical composition of the mineralized domain reveal the unusual enrichment of Ca in the mineralised zone with the depletion of K. We propose that fluid discharging from a crystallizing deep-seated magma, mixing with deep circulating Ca-bearing palaeo-groundwater gave rise to the deposition of scheelite. The scheelite mineralization and the quartz vein emplacement occurred after the Pan-African regional metamorphism.
We have performed x-ray photon correlation spectroscopy (XPCS) measurements on a polymer-bilayer system comprised of 100 nm polystyrene film on top of an 80 nm polybromostyrene film, supported on a Si substrate. In order to distinguish the dynamics at the top interface from that at the polymer-polymer interface we have performed the measurement at grazing incidence. In this geometry, a standing wave is set up in the film. We derive a relation for the intensity of the standing wave and the resulting diffuse scattering. This model is compared with the measured diffuse scattering from which we extract a value of 0.7±0.4 dyne/cm for the surface tension between PS and PBrS at 180C. XPCS was then measured in each of two standing wave conditions, first where diffuse scattering only occurs at the polymer-vacuum interface and then where it only occurs at the interior polymer-polymer interface. The measured time correlation functions for each of the two interfaces show clear differences, with the polymer-polymer interface exhibiting much slower dynamics.
Solid solution series of the type K2Bi8-xSbxSe13, K2-xRbxBi8Se13 as well as K2Bi8Se13-xSx were prepared and the distribution of the atoms (Bi/Sb, K/Rb and Se/S) on different crystallographic sites, the band gaps and their thermoelectric properties were studied. The distribution Se/S appears to be more uniform than the distribution of the Sb and Rb atoms in the β-K2Bi8Se13 structure that shows preference in specific sites in the lattice. Band gap is mainly affected by Sb and S substitution. Seebeck coefficient measurements showed n-type character for of all Se/S members. In the Bi/Sb series an enhancement of p-type character was observed. The thermoelectric performance as well as preliminary high temperature measurements suggest the potential of these materials for high temperature applications.
Lithium niobate single crystal is an excellent material for various optical applications such as frequency conversion, optical switches, optical modulators and others. An automatic diameter control Czochralski crystals growth system has been designed and fabricated. A brief description of the entire system along with software developed has been described. With optimized growth parameters, pure and Fe/Mn doped crystals have been successfully grown using this system. Preliminary characterizations of these crystals have also been presented.
Isolates of Cryptosporidium muris and C. serpentis were characterized from different hosts using nucleotide sequence
analysis of the rDNA 18S and ITS1 regions, and the heat-shock (HSP-70) gene. Phylogenetic analysis confirmed
preliminary evidence that C. muris is not a uniform species. Two distinct genotypes were identified within C. muris; (1)
C. muris genotype A; comprising bovine and camel isolates of C. muris from different geographical locations, and (2) C.
muris genotype B comprising C. muris isolates from mice, a hamster, a rock hyrax and a camel from the same enclosure.
These 2 genotypes may represent separate species but further biological and molecular studies are required for
The intra- and interchain structure of sodium poly(styrenesulphonate) when free and when confined in contrast matched porous Vycor has been investigated by SANS. When confined, a peak is observed whose intensity increases with molecular weight and the 1/q scattering region is extended compared to the bulk. We infer that the chains are sufficiently extended, under the influence of confinement, to highlight the large scale disordered structure of Vycor. The asymptotic behavior of the observed interchain structure factor is ≍ 1/q2 and ≍ 1/q for free and confined chains respectively.
Skeletal maturity in 750 normal Pakistani children (400 males, 350 females) aged 1–18 y was determined by
the Greulich–Pyle atlas system. Male children during first year and female children during first 2 y of life
matured in conformity with Greulich–Pyle standards. After that period mean bone ages were lower than the
American standards up to 15 y in males and 13 y in females (at or around puberty), which may be due to
malnutrition, ill health or other environmental factors. After puberty bone ages were higher than the
American standards indicating earlier maturity in Pakistani than Western children. Hence for the proper
evaluation of skeletal age in a given region, a longitudinal study on individuals in that region to establish
normal standards is necessary.
We have investigated the photophysical properties of surface capped CdS and CdS:Mn nanoparticles in the form of spin coated thin films of the pure nanoparticles and nanoparticle -polymer blends. The organic capping reagent was p-thiocresol. Electroluminescence (EL) devices were fabricated and characterized by their current/voltage characteristics and EL emission performance. This is to our knowledge the first report on Mn doped CdS nanoparticles applied in EL devices with a single layer device structure (ITO/CdS:Mn/Al). Photoluminescence (PL) and PL excitation measurements were performed on CdS:Mn nanoparticles in pyridine dispersion and on thin films. The PL excitation spectrum shows a narrow peak at 390nm. Excitation at this wavelength yields a broad PL spectrum spanning from about 450 to 700nm, which is dominated by a strong emission band at 585nm. This emission is attributed to transitions involving Mn levels in previous works. The EL emission peak is shifted to the red compared to the PL emission spectra. The characteristics and performance of these new types of EL devices will be presented and discussed.