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91.
Jin S Tiefel TH McCormack M Fastnacht RA Ramesh R Chen LH 《Science (New York, N.Y.)》1994,264(5157):413-415
A negative isotropic magnetoresistance effect more than three orders of magnitude larger than the typical giant magnetoresistance of some superlattice films has been observed in thin oxide films of perovskite-like La(0.67)Ca(0.33)MnOx. Epitaxial films that are grown on LaAIO(3) substrates by laser ablation and suitably heat treated exhibit magnetoresistance values as high as 127,000 percent near 77 kelvin and approximately 1300 percent near room temperature. Such a phenomenon could be useful for various magnetic and electric device applications if the observed effects of material processing are optimized. Possible mechanisms for the observed effect are discussed. 相似文献
92.
Aggarwal S Monga AP Perusse SR Ramesh R Ballarotto V Williams ED Chalamala BR Wei Y Reuss RH 《Science (New York, N.Y.)》2000,287(5461):2235-2237
We report the spontaneous formation of uniformly distributed arrays of "tips" (tall conical hillocks) upon oxidation of palladium (Pd) thin films. The formation of the palladium oxide tips depended on the thickness and granularity of the Pd film and on annealing and oxidation conditions. As the Pd film thickness increased from 40 to 200 nanometers, the average height of the tips increased from 0.5 to 1.2 micrometers, their height distribution became broader, and their density decreased from 55 x 10(6) to 12 x 10(6) per square centimeter. Enhanced photoelectron emission from locations corresponding to the tips suggests their possible use in field emission applications. 相似文献
93.
C. Channuntapipat M. Wirthensohn S.A. Ramesh I. Batlle P. Arús M. Sedgley G. Collins 《Plant Breeding》2003,122(2):164-168
Identification of the incompatibility genotypes of almond cultivars is important in breeding programmes for designing crosses and for selecting progeny. This paper describes a novel molecular technique for the identification of S‐alleles in almond based on the use of PCR primers designed from the sequences of the introns without the need for restriction enzyme digestion. Nine specific pairs of primers have been designed for the S1, S2, S5, S7, S8, S9, S10 (putative), S23 and Sf alleles, and these confirmed the S‐allele specificities for 22 of the 23 accessions for which published information is available. This technique provides a precise method for identifying S‐alleles from the genomic DNAs of almond cultivars, and will be useful for confirming the segregation of alleles in breeding progeny. 相似文献
94.
Revadi Santosh V. Giannuzzi Vito Antonio Vetukuri Ramesh R. Walker William B. Becher Paul G. 《Journal of pest science》2021,94(4):1105-1118
Journal of Pest Science - Larval frass in herbivorous lepidopterans is mainly composed of plant-derived material and microbes from the gut. Despite the fact that frass from conspecific larvae... 相似文献
95.
Stenberg Johan A. Sundh Ingvar Becher Paul G. Björkman Christer Dubey Mukesh Egan Paul A. Friberg Hanna Gil José F. Jensen Dan F. Jonsson Mattias Karlsson Magnus Khalil Sammar Ninkovic Velemir Rehermann Guillermo Vetukuri Ramesh R. Viketoft Maria 《Journal of pest science》2021,94(3):665-676
Journal of Pest Science - Biological control, or biocontrol, is the exploitation of living agents (incl. viruses) to combat pestilential organisms (incl. pathogens, pests, and weeds) for diverse... 相似文献
96.
Wazir S Lakra Nachimuthu Sivakumar Mukunda Goswami & Ramesh R Bhonde 《Aquaculture Research》2006,37(1):18-24
Two new cell culture systems namely epitheloid cells of Lates (LCE) and fibroblastic cells of Lates (LCF) have been developed from fry and fingerling of the economically important brackishwater fish Lates calcarifer. Primary cultures were initiated by explant technique using caudal fin of fingerling and whole body tissue of the fry. The nutritional requirements and the growth pattern in response to different culture environment were similar for the two cell cultures. The culture medium used was Leibovitz‐15 supplemented with 20% fetal bovine serum (FBS) and 1% fish serum. The LCE comprised of epithelioid cells and LCF cells were fibroblastic. With a split ratio of 1:2, the confluency of cells was attained in 8–10 days at an incubation temperature of 28°C. The cells were found to grow well in a wide range of temperature (24–32°C) and stable at 20 and 36°C. The growth rate of LCF and LCE cells increased proportionately with the concentration of FBS from 5% to 20%. A decrease of serum level to 10% after eight subcultures produced no apparent change in cell morphology and growth rate. The viability of cells was found to be 70% when revived after a month of storage in liquid nitrogen (?196°C). 相似文献
97.
Nafeez Ahmed Abdul Abdul Majeed Seepoo Taju Gani Vimal Sugumar Suryakodi Selvam Badhusha Allahbagash Abdul Nazar Abdul kuthoos Ramesh Kumar Palsamy Paknikar Kishore M. Jyutika M. Rajwade Sait Sahul Hameed Azeez 《Journal of fish diseases》2022,45(1):121-139
Five novel permanent cell lines have been established from gill, heart, kidney, eye and fin of snubnose pompano, Trachinotus blochii. They were designated as snubnose pompano gill (SPG), snubnose pompano heart (SPH), snubnose pompano kidney (SPK), snubnose pompano eye (SPE) and snubnose pompano fin (SPF), respectively. All these cell lines were characterized and cryopreserved successfully at different passage levels. Cell lines were passaged every alternate day; SPG, SPH, SPK, SPE and SPF cell lines attained passage levels of 68, 74, 82, 79 and 106, respectively, since the initiation of their development in 2019. The cell lines grew well in Leibovitz's 15 medium containing 15% foetal bovine serum at 28°C. Immunophenotyping of the cell lines revealed the presence of fibronectin and pancytokeratin. No mycoplasma contamination was found. The transfection study revealed the gene expression efficiency of these cell lines by expressing the green fluorescent protein (GFP). The authentication on origin of cell lines from T. blochii was confirmed by amplification of species-specific mitochondrial cytochrome oxidase I gene. The results showed the susceptibility of these cell lines to fish nodavirus (FNV) and tilapia lake virus (TiLV) and resistance to cyprinid herpesvirus 2 (CyHV-2). The FNV infection in the cell lines was confirmed by RT-PCR, Western blot, ELISA and immunocytochemistry, while TiLV infection was confirmed by RT-PCR assay. These results revealed that these cell lines are suitable for virological and foreign gene expression studies. 相似文献
98.
99.
The impact of acute and sublethal toxicity of a synthetic organochlorine pesticide lindane on some haematological and biochemical parameters of a freshwater fish Cyprinus carpio was estimated. The median lethal concentration of lindane for 24 h was 0.38 ppm. During acute treatment (24 h), hemoglobin (Hb), hematocrit (Hct) and erythrocyte (RBC) values were decreased, whereas leucocyte (WBC) count increased in the pesticide treated fish. The hematological indices like mean cellular volume (MCV), mean cellular hemoglobin (MCH) and mean cellular hemoglobin concentration (MCHC) were decreased when compared to control group. Biochemical profiles like plasma glucose and protein levels were increased in lindane exposed fish showing a percent increase of 50.36 and 3.98 at the end of 24 h treatment. However, glycogen content in liver and muscle were decreased showing a percent decrease of 21.70 and 1.74. In sublethal treatment (1/10th of LC50 24 h value, 0.038 ppm), RBC count was decreased whereas WBC count increased in the pesticide treated fish throughout the study period (25 days). Hb and Hct values were decreased up to 10th day and after that recovered showing a significant increase in the rest of the study period. Similarly, a biphasic response was observed in the value of MCV, MCH and MCHC. Plasma glucose level was significantly increased while plasma protein level decreased throughout the study period. Further, glycogen level in muscle and liver were showed a mixed trend. In the present study, the pesticide lindane caused alterations on haematological and biochemical parameters of C. carpio and these alterations can be used as non specific biomarkers in pesticide contaminated aquatic ecosystem. 相似文献
100.
Raghavendra Kerur Vishwanath Ramesh Kurubarahalli Bhoothanna Rachana Rajan Remani Mahendra Chowdanayak Singh Surender Kumar Chander Subhash 《Phytoparasitica》2023,51(2):227-239
Phytoparasitica - Thrips are economically important pests of crops and vectors of viral diseases worldwide. Invasion and outbreak of thrips have recently caused havoc in agricultural and... 相似文献