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991.
Mariia Belinskaia Tomas Zurawski Seshu Kumar Kaza Caren Antoniazzi J. Oliver Dolly Gary W. Lawrence 《International journal of molecular sciences》2022,23(2)
Nerve growth factor (NGF) is known to intensify pain in various ways, so perturbing pertinent effects without negating its essential influences on neuronal functions could help the search for much-needed analgesics. Towards this goal, cultured neurons from neonatal rat trigeminal ganglia—a locus for craniofacial sensory nerves—were used to examine how NGF affects the Ca2+-dependent release of a pain mediator, calcitonin gene-related peptide (CGRP), that is triggered by activating a key signal transducer, transient receptor potential vanilloid 1 (TRPV1) with capsaicin (CAP). Measurements utilised neurons fed with or deprived of NGF for 2 days. Acute re-introduction of NGF induced Ca2+-dependent CGRP exocytosis that was inhibited by botulinum neurotoxin type A (BoNT/A) or a chimera of/E and/A (/EA), which truncated SNAP-25 (synaptosomal-associated protein with Mr = 25 k) at distinct sites. NGF additionally caused a Ca2+-independent enhancement of the neuropeptide release evoked by low concentrations (<100 nM) of CAP, but only marginally increased the peak response to ≥100 nM. Notably, BoNT/A inhibited CGRP exocytosis evoked by low but not high CAP concentrations, whereas/EA effectively reduced responses up to 1 µM CAP and inhibited to a greater extent its enhancement by NGF. In addition to establishing that sensitisation of sensory neurons to CAP by NGF is dependent on SNARE-mediated membrane fusion, insights were gleaned into the differential ability of two regions in the C-terminus of SNAP-25 (181–197 and 198–206) to support CAP-evoked Ca2+-dependent exocytosis at different intensities of stimulation. 相似文献
992.
Yashbir Singh Shivay Dinesh Kumar Rajendra Prasad 《Nutrient Cycling in Agroecosystems》2008,81(3):229-243
Zinc deficiency is prevalent worldwide and is a barrier in achieving yield targets in crops. It is also now recognized as
a leading risk factor for disease in humans in developing countries. Generally, soil application of 5–17 kg Zn ha−1 y−1 (25–85 kg zinc sulphate heptahydrate ha−1 y−1) or more is recommended for rice. However, in the developing rice-growing countries of Asia, zinc sulphate of desired quality
is not readily available and is also quite expensive, and the farmers generally fail to apply Zn, resulting in crop yield
loss in rice. Availability of zinc-enriched urea (ZEU) makes possible not only the availability of quality zinc, but also
assures its application. Therefore, field experiments were conducted for two consecutive years at the research farm of Indian
Agricultural Research Institute, New Delhi, India, during rainy (rice) and winter (wheat) seasons of 2004–2006 on a sandy
clay-loam soil to study the effect of various concentrations of zinc enrichment of urea on productivity, zinc concentrations,
its uptake and use indices of aromatic rice–wheat cropping system. Eight treatments comprising prilled urea (PU) and 0.5,
1.0, 1.5, 2.0, 2.5, 3.0 and 3.5% zinc-enriched urea, replicated three times, were compared in a randomized block design. The
enrichment of PU was done through zinc oxide containing 80% zinc. The results of this study revealed that the zinc-enriched
urea (ZEU) had a significant effect on growth, yield attributes and yields of aromatic rice. Highest values for all these
attributes and yields were recorded at the highest enrichment (3.5%) of the PU with zinc. The highest zinc concentration and
uptake in rice grain and straw were also significantly higher with the highest level (3.5%) of zinc enrichment. The highest
total zinc uptake recorded was 1,168 and 1,353 g ha−1, during 2004 and 2005, respectively, with 3.5% ZEU. However, a major increase in grain yield of rice was recorded up to 1.0%
zinc enrichment. The residual effect of zinc-enriched urea on succeeding wheat yield and zinc uptake was significant only
at a higher level of zinc-enriched urea and only in the second year of study. Overall, 1.0% zinc-enriched urea recorded significantly
higher productivity and zinc uptake over PU in the rice–wheat cropping system and is recommended for Delhi and adjoining areas.
The recommendation is also made keeping in view the fact that with increased levels of zinc enrichment of urea, the partial
factor productivity, agronomic efficiency, apparent recovery and physiological efficiency of applied zinc in a rice–wheat
system decreased significantly. Considering all the economic parameters (benefit, benefit:cost ratio, IR gained IR−1 invested in zinc), 1.0% ZEU proved the most economic source for aromatic rice–wheat cropping system and therefore is recommended
for rice–wheat cropping system in Delhi and adjoining areas of north India. 相似文献
993.
Jaspal Singh Sanjeev Kumar N. K. Verma 《Journal of Materials Science: Materials in Electronics》2014,25(5):2267-2272
Cd1?xNixSe (x = 0.0, 0.02, 0.05 and 0.1) nanoparticles have been synthesized by chemical route. X-ray diffraction analysis shows crystalline nature of synthesized nanoparticles possessing wurtzite phase having hexagonal structure. Transmission electron microscopy depicts spherical morphology and uniform particle size distribution of pure and Ni-doped CdSe nanoparticles. The blue-shift in band gap has been observed with Ni-doping concentration. Photoluminescence study shows the presence of intrinsic defects (VCd–VSe) in the synthesized nanoparticles. Electron spin resonance (ESR) analysis reveals the long range ferromagnetic ordering in pure and doped nanoparticles. ESR study also indicates that Ni ions exist in +2 oxidation state in host nanoparticles. The magnetic hysteresis (M-H) loops display ferromagnetism at room temperature in pure and Ni-doped CdSe nanoparticles. The increase of ferromagnetic behavior has been observed with Ni-doping concentration. M-H analyses indicate that defects and carrier mediated exchange interactions are responsible for ferromagnetic ordering, in the present study. 相似文献
994.
Susanta Kumar Saha Ashis Banerjee Shashwat Banerjee Susmita Bose 《Materials science & engineering. C, Materials for biological applications》2009,29(7):2294-2301
Hydroxyapatite (HA) nanopowder was synthesized by reverse microemulsion technique using calcium nitrate and phosphoric acid as starting materials in aqueous phase. Cyclohexane, hexane, and isooctane were used as organic solvents, and Dioctyl sulfosuccinate sodium salt (AOT), dodecyl phosphate (DP), NP5 (poly(oxyethylene)5 nonylphenol ether), and NP12 (poly(oxyethylene)12 nonylphenol ether) as surfactants to make the emulsion. Effect of synthesis parameters, such as type of surfactant, aqueous to organic ratio (A/O), pH and temperature on powder characteristics were studied. It was found that the surfactant templates played a significant role in regulating the morphology of the nanoparticle. Hydroxyapatite nanoparticle of different morphologies such as spherical, needle shape or rod-like were obtained by adjusting the conditions of the emulsion system. Synthesized powder was characterized using X-ray diffraction (XRD), BET surface area and transmission electron microscopy (TEM). Phase pure HA nanopowder with highest surface area of 121 m2/g were prepared by this technique using NP5 as a surfactant. Densification studies showed that this nanoparticle can give about 98% of their theoretical density. In vitro bioactivity of the dense HA compacts was confirmed by excellent apatite layer formation after 21 days in SBF solution. Cell material interaction study showed good cell attachment and after 5 days cells were proliferated on HA compacts in OPC1 cell culture medium. The results imply this to be a versatile approach for making hydroxyapatite nanocrystals with controlled morphology and excellent biocompatibility. 相似文献
995.
Raj Kumar Singh Sunil Kumar Sinha A. Rama Rao 《Nuclear Engineering and Design》2009,239(10):1760-1767
The primary function of the shut down system in a nuclear reactor is to terminate any reactivity transient occurring in the core during its entire design life. Normally there is more than one system, which are independent and diverse in its mode of operation. They consist of quick acting mechanisms like dropping of safety rods by gravity, poison injection, etc. Typically in liquid poison injection system wherein high flow velocities are involved, there is significant fluid structure interaction associated with cyclic shock transients in the system. One such phenomenon has been captured and analyzed to understand the dynamics involved in the loop. The trends of loop pressure and vibration indicated presence of more than two pressure transients after complete injection of poison. The first transient arrived after 1.44 s and the second after 0.75 s. The reverse pressure pulses that manifested in the loop as a result of fast injection of fluid has been mathematically characterized by solving basic fluid balance equations. Possibility of ball lifting due to momentum pulse is also discussed. 相似文献
996.
A simulation study to assess the performance of a renewable energy (solar-biomass) based single effect LiBr-water absorption chiller suitable for residential applications was conducted. The model took into account the characteristics of all the components of the system. Using Bangkok meteorological data and component specifications from manufacturers and other sources, the performances of solar collector, storage tank, biomass gasifier and boiler, and the absorption cooling system, as well as the overall system performance on a daily and monthly basis has been evaluated. The chiller and overall system coefficient of performances was found to be 0.7 and 0.55 respectively and the biomass (charcoal) consumption for 24 h operation was 24.44 kg/day. To validate the model formulation and its predictions, experimental observations of a similar system (same chiller size) were compared with the model results. The results of the study indicate that solar-biomass hybrid air conditioning for tropical locations for residential applications is feasible, and can replace conventional vapor compression systems, thus reducing the need for fossil fuel based energy systems for cooling purposes. 相似文献
997.
The properties of concrete using coconut shell as coarse aggregate were investigated in an experimental study. Compressive, flexural, splitting tensile strengths, impact resistance and bond strength were measured and compared with the theoretical values as recommended by the standards. For the selected mix, two different water–cement ratios have been considered to study the effect on the flexural and splitting tensile strengths and impact resistance of coconut shell concrete. The bond properties were determined through pull-out test. Coconut shell concrete can be classified under structural lightweight concrete. The results showed that the experimental bond strength of coconut shell concrete is much higher than the bond strength as estimated by BS 8110 and IS 456:2000 for the mix selected. 相似文献
998.
Keshav Kumar Nepal Jin Cheol Yoo Jae Kyung Sohng 《Journal of Bioscience and Bioengineering》2010,110(1):109-112
Aminoglycoside antibiotics can be classified into two major groups; streptamine containing and 2-deoxystreptamine containing antibiotics. Here, we report a biosynthetic approach for the fusion of spectinomycin and kanamycin biosynthetic gene clusters to yield the new aminoglycoside derivative, oxykanamycinC, in a non-aminoglycoside producing heterologous host. 相似文献
999.
The effect of MgO additive on the structural, microstructural and hardness properties of zirconia mullite (MUZ) has been discussed. The MgO additive in MUZ not only stabilizes the cubic zirconia phase but also acts as a sintering aid for the formation of cross-linked mullite grains. The electron micrographs of plasma fused MgO–MUZ shows a uniform arrangement of platelet structure of mullite and dendrite structure of zirconia on mullite surface. The micrograph of plasma sintered composites shows a ladder like structure and a complete cross-linked mullite grains whereas the surface morphology of conventionally sintered composites clearly indicates the presence of small and big grains close packed to each other. Appreciable hardness and higher optical band gap have been observed for plasma fused MgO–MUZ composites. A complete dissociation of sillimanite and zircon has been occurred in plasma fused composites for the complete conversion of MUZ whereas the complete dissociation of sillimanite and zircon has not observed in plasma sintered and conventionally sintered composites. These observations have been realized from the X-ray diffraction and Fourier transform infrared studies. 相似文献
1000.
Anna Fensel Slobodanka Tomic Vikash Kumar Milan Stefanovic Sergey V. Aleshin Dmitry O. Novikov 《Informatik-Spektrum》2013,36(1):46-57
As the urgent need for efficient and sustainable energy usage becomes ever more apparent, interest in Smart Homes is on the rise. The SESAME-S project (SEmantic SmArt Metering – Services for Energy Efficient Houses) uses semantically linked data to actively assist end-consumers in making well-informed decisions and controlling their energy consumption. By integrating smart metering and home automation functionality, SESAME-S works to effectively address the potential mass market of end-consumers with an easily customizable solution that can be widely implemented in domestic or business environments, with expected savings of over 20?% from the total energy bill. The developed system is a basis for conceptualizing, demonstrating, and evaluating a variety of innovative end-consumer services and their user interface paradigms. In this paper, we present the SESAME-S system as a whole and discuss the semantically enabled services, demonstrating that such systems may have broad acceptance in the future. The data obtained through such systems will be invaluable for future global energy-efficiency strategies and businesses. 相似文献