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921.
Au nano-clusters and nanoparticles (NPs) have been widely utilized in various electronic, optoelectronic, and bio-medical applications due to their great potentials. The size, density and configuration of Au NPs play a vital role in the performance of these devices. In this paper, we present a systematic study on the self-assembled hexagonal Au voids, nano-clusters and NPs fabricated on GaN (0001) by the variation of annealing temperature and deposition amount. At relatively low annealing temperatures between 400 and 600°C, the fabrication of hexagonal shaped Au voids and Au nano-clusters are observed and discussed based on the diffusion limited aggregation model. The size and density of voids and nano-clusters can systematically be controlled. The self-assembled Au NPs are fabricated at comparatively high temperatures from 650 to 800°C based on the Volmer-Weber growth model and also the size and density can be tuned accordingly. The results are symmetrically analyzed and discussed in conjunction with the diffusion theory and thermodynamics by utilizing AFM and SEM images, EDS maps and spectra, FFT power spectra, cross-sectional line-profiles and size and density plots. 相似文献
922.
Amitabh Singh Sarita Singh Monisha Kesherwani T. D. Singh V. P. Singh V. B. Pandey 《Archives Of Phytopathology And Plant Protection》2013,46(15):1450-1453
The isomeric alkaloids jatrorrhizine and columbamine isolated from the whole plant of Argemone mexicana were assessed against spore germination of some fungi, e.g. Alternaria cajani, Bipolaris sp., Helminthosporium sp., Fusarium udum and Curvularia sp. Both the alkaloids were effective against most of the fungi tested. Jatrorrhizine was highly effective against spore germination of Bipolaris sp., Fusarium udum and Curvularia sp. at 5000 ppm concentration, whereas columbamine was highly effective against Alternaria cajani, Helminthosporium sp. and Fusarium udum at 5000 ppm. 相似文献
923.
The paper deals with the presence of interparietal bone in a single or more pieces out of a series of 1,500 skulls of the Anthropology Museum of Anatomy Department, GSVM Medical College, Kanpur. It was found to be present in 0.3% of cases. It has no morphological importance but it certainly has a morphogenetic bearing. 相似文献
924.
Panda Debashish Mohanty Subham Allen Maximilian L. Dheer Arjun Sharma Ajay Pandey Puneet Lee Hang Singh Randeep 《Acta theriologica》2023,68(2):129-141
Mammal Research - Scavenging of carrion is an important ecological process that influences ecological communities and food webs. The competitive inter- and intra-specific interactions in... 相似文献
925.
Rosemary Tomichan Avinash Sharma K. Akash Adeeb Ahmad Siddiqui Amit Dubey Tarun Kumar Upadhyay Deepak Kumar Sadanand Pandey Rupak Nagraik 《Luminescence》2023,38(7):1102-1110
The review discusses the diagnostic application of biosensors as point-of-care devices in the COVID-19 pandemic. Biosensors are important analytical tools that can be used for the robust and effective detection of infectious diseases in real-time. In this current scenario, the utilization of smart, efficient biosensors for COVID-19 detection is increasing and we have included a few smart biosensors such as smart and intelligent based biosensors, plasmonic biosensors, field effect transistor (FET) biosensors, smart optical biosensors, surface enhanced Raman scattering (SERS) biosensor, screen printed electrode (SPE)-based biosensor, molecular imprinted polymer (MIP)-based biosensor, MXene-based biosensor and metal–organic frame smart sensor. Their significance as well as the benefits and drawbacks of each kind of smart sensor are mentioned in depth. Furthermore, we have compiled a list of various biosensors which have been developed across the globe for COVID-19 and have shown promise as commercial detection devices. Significant challenges in the development of effective diagnostic methods are discussed and recommendations have been made for better diagnostic outcomes to manage the ongoing pandemic effectively. 相似文献
926.
Meena Rajendra K. Negi Nitika Shankhwar Rajeev Bhandari Maneesh S. Kant Rama Pandey Shailesh Kumar Narinder Sharma Rajesh Ginwal Harish S. 《Journal of plant research》2023,136(4):483-499
Journal of Plant Research - The present study was conducted to understand the key ecological and biological questions of conservation importance in Drepanostachyum falcatum which aimed to map... 相似文献
927.
Recombinant feline leukemia virus genes detected in naturally occurring feline lymphosarcomas. 总被引:6,自引:3,他引:3 下载免费PDF全文
Using a polymerase chain reaction strategy aimed at detecting recombinant feline leukemia virus (FeLV) genomes with 5' env sequences originating from an endogenous source and 3' env sequences resulting from FeLV subgroup A (FeLV-A), we detected recombinant proviruses in approximately three-fourths of naturally occurring thymic and alimentary feline lymphosarcomas (LSAs) and one-third of the multicentric LSAs from cats determined to be FeLV capsid antigen positive by immunofluorescence assay. In contrast, only 1 of 22 naturally arising FeLV-negative feline LSAs contained recombinant proviruses, and no recombinant env gene was detected in seven samples from normal tissues or tissues from FeLV-positive animals that died from other diseases. Four preferred structural motifs were identified in the recombinants; one is FeLV-B like (recognizing that FeLV-B itself is a product of recombination between FeLV-A and endogenous env genes), and three contain variable amounts of endogenous-like env gene before crossing over to FeLV-A-related sequences: (i) a combination of full-length and deleted env genes with recombination at sites in the middle of the surface glycoprotein (SU), (ii) the entire SU encoded by endogenous-like sequences, and (iii) the entire SU and approximately half of the transmembrane protein encoded by endogenous-like sequences. Additionally, three of the thymic tumors contained recombinant proviruses with mutations in the vicinity of the major neutralizing determinant for the SU protein. These molecular genetic analyses of the LSA DNAs correspond to our previous results in vitro and support the occurrence and association of viral recombinants and mutants in vivo in FeLV-induced leukemogenesis. 相似文献
928.
A fungal culture isolated from a local soil sample which showed antifungal activity and produced cyclosporin A, was identified
asTolypocladium inflatum. The culture grew best in a medium containing 1% maltose (pH 5–6) when inoculated with a one-day-old inoculum at 2% (V/V) concentration. Under batch fermentation conditions, growth and cyclosporin A production were better in complex media (24.6
g biomass and 205 mg cyclosporin A per liter) in comparison with synthetic media (6.84 g biomass and 35 mg cyclosporin A per
liter). While addition of peptone increased culture growth (high biomass yield), supplementation with casein acid hydrolyzate
favored cyclosporin A production. 相似文献
929.
R. M. Pandey 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1984,68(1-2):121-125
Summary Genetical studies on grain yield and its contributing traits were made in a six parent complete diallel in the F1 and F2 generations of one of the most widely grown grain species of grain amaranths (Amaranthus hypochondriacus L.). Graphical analysis indicated that epistasis exists for 1,000-grain weight in the F1. Grain weight/panicle, yield/plant and harvest index indicated absence of non-allelic gene interaction. The harvest index in the F1 and F2 and grain weight/ panicle, 1,000-grain weight, yield/plant in the F2 appeared to be controlled by overdominance effects. Higher grain yield appeared to be associated with dominant genes. Both additive and non-additive gene effects were responsible for the genetic variation in the diallel population. However, dominance variance was more important than additive variance in grain yield/ plant and harvest index in the F1 and F2. For 1,000-grain weight additive genetic variance was more important in the F1 and non-additive in F2. There was overdominance of a consistent nature in the two analyses for harvest index in the F1 and F2, grain weight/ panicle, 1,000-grain weight and yield/plant in the F2 and partial dominance for 1,000-grain weight in the F1. 相似文献
930.
Changes in the concentration of progesterone and estradiol-17beta were measured by radioimmunoassay in 11 primiparous and 17 multiparous buffaloes at estrus and daily post insemination and in 6 nonbred buffaloes at 6 hour intervals from 4 days before expected estrus to one day after estrus. Plasma progesterone concentration at estrus was 0.1 ng/ml which rose to a peak level of 3.47 ng/ml on day 17. It fluctuated around this level in those animals which conceived, but followed a declining trend in those which failed to do so and attained lowest values on the day of next estrus. Temporal changes of the hormone revealed that the occurrence of major decline varjed between 16 and 62 h before estrus. The average concentration in milk was about three to four times higher than in plasma. The concentration of estradiol-17beta about 23.50 pg/ml at estrus and fluctuated around 10 pg/ml in animals that returned to estrus with a peak around estrus. Temporal changes of hormone revealed that peak level occurred 8-17 h before estrus. The concentration of estradiol in pregnant animals fluctuated around 10 pg/ml. The concentration in milk was about 2-3 times higher than in plasma. There was no significant (P > 0.05) difference in the concentrations of progesterone and estradiol-17beta between primiparous and multiparous animals. 相似文献