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1.
Sunspots, dark magnetic regions occurring at low latitudes on the Sun's surface, are tracers of the magnetic field generated by the dynamo mechanism. Recent solar dynamo models, which use the helioseismically determined solar rotation, indicate that sunspots should form at high latitudes, contrary to observations. We present a dynamo model with the correct latitudinal distribution of sunspots and demonstrate that this requires a meridional flow of material that penetrates deeper than hitherto believed, into the stable layers below the convection zone. Such a deep material flow may have important implications for turbulent convection and elemental abundance in the Sun and similar stars. 相似文献
2.
Seroprevalence of Peste des petits ruminants in cattle and buffaloes from Southern Peninsular India 总被引：1，自引：1，他引：0
Balamurugan V Krishnamoorthy P Veeregowda BM Sen A Rajak KK Bhanuprakash V Gajendragad MR Prabhudas K 《Tropical animal health and production》2012,44(2):301-306
This study describes seroprevalence of Peste des petits ruminants (PPR) in cattle and buffaloes carried out during the period 2009–2010 using the randomly collected serum samples from different
parts of Southern peninsular India. The report presents the results of PPR virus (PPRV)—specific antibodies in situations
where either the subclinical or inapparent or non-lethal infection was there in cattle and buffaloes. A total of 2,548 serum
samples [cattle = 1,158, buffaloes = 1,001, sheep = 303 and goat = 86] were collected and screened for PPRV antibodies by
using a PPR monoclonal antibody-based competitive ELISA kit. Analysis of 2,159 serum samples indicates an overall 4.58% prevalence
of PPRV antibody in cattle and buffaloes. The presence of PPRV-specific antibodies demonstrates that cattle and buffaloes
are exposed to PPR infection naturally, and the transmission mode may be direct or indirect. Further, it implies the importance
of bovines as subclinical hosts for the virus besides widespread presence of the disease in sheep and goats in the country. 相似文献
3.
Parishmita Handique Hemanta Pokhrel Binod Kalita Raktim Sarmah Abdul Malik Ahmed Kaustabh Bhagawati Arnab Narayan Patowary 《Aquaculture Research》2020,51(5):1973-1979
The present study was conducted to evaluate the …effect of dietary selenium on growth performance and antioxidant enzymes activity in Cirrhinus mrigala for a period of 45 days. Four numbers of experimental diets were prepared, Tc for Control (0 mg organic selenium/kg of diet), T1 (2.5 mg organic selenium/kg of diet), T2 (5.0 mg organic selenium/kg of diet) and T3 (10 mg organic selenium/kg of diet). The water quality parameters (temperature, DO, pH, conductivity, hardness, ammonia, nitrate and nitrite) were found to be insignificant (p > .05) among all the treatments. Superoxidase dismutase (SOD) was found to be significantly highest in T2 (6.10 ± 0.07) when compared with the other treatments. Similarly, catalase (CAT) activity in T1 (13.21 ± 0.13) was significantly (p < .05) different with that of Control, T2 and T3. Present study also revealed that 2.5mg organic selenium/kg supplemented diet (T1) showed highest results in net weight gain (15.55 ± 1.36 g), net weight gain percentage (185.88 ± 8.98%) and SGR (2.35 ± 0.06 g) compared with other experimental diet. 相似文献
4.
Vinayagamurthy Balamurugan Paramasivam Saravanan Arnab Sen Kaushal Kishor Rajak Gnanavel Venkatesan Paramanandham Krishnamoorthy Veerakyathappa Bhanuprakash Raj Kumar Singh 《Journal of veterinary science (Suw?n-si, Korea)》2012,13(3):279-285
This study measured the clinical prevalence of peste des petits ruminants (PPR) among sheep and goats in India between 2003 and 2009 by analyzing clinical samples from suspected cases of PPR that were submitted to the Rinderpest and Allied Disease Laboratory, Division of Virology, IVRI, Mukteswar for PPR diagnosis. PPR outbreaks were confirmed by detecting PPR virus (PPRV)-specific antigen in the clinical samples. Clinical samples (blood, nasal swabs, spleen, lymph node, kidney, liver, intestine, and pooled tissue materials) were taken from a total of 592 sheep and 912 goats in different states of India and screened for the presence of PPRV antigen using a monoclonal antibody-based sandwich ELISA kit. A total of 20, 38, and 11 laboratory-confirmed PPR outbreaks occurred among sheep, goat, and combined sheep and goat populations, respectively. Our findings provide evidence of widespread PPR endemicity in India. The underlying reasons could be variations in husbandry practices in different geographical regions, agro-climatic conditions, and livestock migration. Furthermore, decrease in the number of PPR outbreaks over time might be due to the effectiveness of current live PPR vaccines and timely vaccination of target species. Vaccination against PPR has been practiced in India since 2002 to control this disease. 相似文献
5.
Spatio-temporal assessment of the above ground biomass (AGB) is a cumbersome task due to the difficulties associated with
the measurement of different tree parameters such as girth at breast height and height of trees. The present research was
conducted in the campus of Birla Institute of Technology, Mesra, Ranchi, India, which is predominantly covered by Sal (Shorea robusta C. F. Gaertn). Two methods of regression analysis was employed to determine the potential of remote sensing parameters with
the AGB measured in the field such as linear regression analysis between the AGB and the individual bands, principal components
(PCs) of the bands, vegetation indices (VI), and the PCs of the VIs respectively and multiple linear regression (MLR) analysis
between the AGB and all the variables in each category of data. From the linear regression analysis, it was found that only
the NDVI exhibited regression coefficient value above 0.80 with the remaining parameters showing very low values. On the other
hand, the MLR based analysis revealed significantly improved results as evidenced by the occurrence of very high correlation
coefficient values of greater than 0.90 determined between the computed AGB from the MLR equations and field-estimated AGB
thereby ascertaining their superiority in providing reliable estimates of AGB. The highest correlation coefficient of 0.99
is found with the MLR involving PCs of VIs. 相似文献
6.
Hall N Karras M Raine JD Carlton JM Kooij TW Berriman M Florens L Janssen CS Pain A Christophides GK James K Rutherford K Harris B Harris D Churcher C Quail MA Ormond D Doggett J Trueman HE Mendoza J Bidwell SL Rajandream MA Carucci DJ Yates JR Kafatos FC Janse CJ Barrell B Turner CM Waters AP Sinden RE 《Science (New York, N.Y.)》2005,307(5706):82-86
7.
Colson JW Woll AR Mukherjee A Levendorf MP Spitler EL Shields VB Spencer MG Park J Dichtel WR 《Science (New York, N.Y.)》2011,332(6026):228-231
Covalent organic frameworks (COFs), in which molecular building blocks form robust microporous networks, are usually synthesized as insoluble and unprocessable powders. We have grown two-dimensional (2D) COF films on single-layer graphene (SLG) under operationally simple solvothermal conditions. The layered films stack normal to the SLG surface and show improved crystallinity compared with COF powders. We used SLG surfaces supported on copper, silicon carbide, and transparent fused silica (SiO(2)) substrates, enabling optical spectroscopy of COFs in transmission mode. Three chemically distinct COF films grown on SLG exhibit similar vertical alignment and long-range order, and two of these are of interest for organic electronic devices for which thin-film formation is a prerequisite for characterizing their optoelectronic properties. 相似文献
8.
Gardner MJ Bishop R Shah T de Villiers EP Carlton JM Hall N Ren Q Paulsen IT Pain A Berriman M Wilson RJ Sato S Ralph SA Mann DJ Xiong Z Shallom SJ Weidman J Jiang L Lynn J Weaver B Shoaibi A Domingo AR Wasawo D Crabtree J Wortman JR Haas B Angiuoli SV Creasy TH Lu C Suh B Silva JC Utterback TR Feldblyum TV Pertea M Allen J Nierman WC Taracha EL Salzberg SL White OR Fitzhugh HA Morzaria S Venter JC Fraser CM Nene V 《Science (New York, N.Y.)》2005,309(5731):134-137
We report the genome sequence of Theileria parva, an apicomplexan pathogen causing economic losses to smallholder farmers in Africa. The parasite chromosomes exhibit limited conservation of gene synteny with Plasmodium falciparum, and its plastid-like genome represents the first example where all apicoplast genes are encoded on one DNA strand. We tentatively identify proteins that facilitate parasite segregation during host cell cytokinesis and contribute to persistent infection of transformed host cells. Several biosynthetic pathways are incomplete or absent, suggesting substantial metabolic dependence on the host cell. One protein family that may generate parasite antigenic diversity is not telomere-associated. 相似文献
9.
Arnab Banerjee Jayanta Kumar Datta Naba Kumar Mondal 《Frontiers of Agriculture in China》2010,4(3):341-351
Field experiments were conducted with mustard (Brassica campestris cv. B9) consecutively for three years (2005, 2006 and 2007) in the Crop Research and Seed Multiplication Farm of Burdwan University, Burdwan, West Bengal, India. In the first year, varietal screening of mustard under recommended dose of chemical fertilizer (100:50:50) were performed with seven mustard varieties during November 2005 to February 2006. In the second year, two experiments were conducted to study the effects of six different combined doses of chemical fertilizer and biofertilizer and six different levels of growth retardant cycocel. In the third year, six different levels of compost along with the best screened dose of growth retardant (CCC-300 ppm) and the best combined dose of biofertilizer and chemical fertilizer (3/4thchemical fertilizer:1/4th biofertilizer) from the previous year were applied to study the effects on agronomic traits and growth attributes of mustard, and the field data were analyzed statistically. The variety B9 recorded a significant higher seed yield along with other yield contributing factors, which was found to be superior to other varieties under old alluvial soil of Burdwan, West Bengal, India, in 2005. In 2006 and 2007, seed yield was found to be the best for CCC-300 ppm treatment and the best combined dose of biofertilizer and chemical fertilizer was found to be 3/4th chemical fertilizer:1/4th biofertilizer. In 2007, the best yield was given by the treatment of 7.5 t·hm?2 compost along with the best dose of growth retardant cycocel and the best combined dose of biofertilizer and chemical fertilizer. 相似文献
10.
Vinayagamurthy Balamurugan Arnab Sen Gnanavel Venkatesan Vandana Bhanot Vineeta Yadav Veerakyathappa Bhanuprakash Raj Kumar Singh 《Journal of veterinary science (Suw?n-si, Korea)》2012,13(2):203-206
In this study, peste des petits ruminants virus (PPRV) was detected in frozen pooled tissue samples from a dead Asiatic lion (Panthera leo persica). The samples were negative for canine distemper virus and positive for PPRV nucleic acids when tested with one-step RT-PCR using the appropriate virus-specific primers. Subsequent amplification, cloning, and sequencing of the partial nucleocapsid, matrix, and fusion genes confirmed the presence of PPRV nucleic acid. Comparative sequence and phylogenetic analyses of the structural genes of the isolated virus confirmed that the virus belonged to Asian lineage IV and was closely related to PPRV circulating in India. 相似文献