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91.
Battista JR Cox MM Daly MJ Narumi I Radman M Sommer S 《Science (New York, N.Y.)》2003,302(5645):567-8; author reply 567-8
92.
F.S. Hamid Tahira Ahmad 《农业科学与技术》2006,7(1):14-22
Field experiment was conducted on mature tea bushes of Qi-Men variety at two different altitudes from sea level i.e. at National Tea Research Institute Shinkiari (1000 m) and on farmer's field in Konsh valley at village Battal (1500 m). Different levels of nitrogen with constant dose of phosphorus and potassium were applied to observe the optimal dose of nutrients for highest yield under local edaphic conditions. The experiment was repeated for three consecutive years. The highest yield of fresh tea leaves were obtained by the application of 420 kg ha^-1 N followed by the application of 360 kg ha^-1 N at 1000 masl. The highest dose of nitrogen also reduced significantly the soil pH in the upper (0-15cm) layer depth during 1998 and 1999. During the year 2000, the reduction in soil pH was observed by the application of highest dose of nitrogen but was non-significant at 5% level. The lower soil depth (15-30 cm) showed the reduction in pH with the highest dose of nitrogen during the experimental year but was statistically non significant.
At the higher altitude of 1500 masl the highest yield of fresh tea leaves was obtained by the application of 420 kg ha^-1 during the experimental years but the increase was significant during the year 1999 and 2000. The yield of the fresh tea leaves was positively correlated with the amount of nitrogen application at both the altitudes. The increasing amount of nitrogen decreased the soil pH at both the depths of 0-15cm and 15-30cm. Unlike the lower altitude (1000 m) there was no any significant reduction in the soil pH during 1998 and 1999. A significant reduction in soil pH was found in the year 2000. 相似文献
93.
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95.
Ahmad HA 《The Journal of Applied Poultry Research》2011,20(4):463-473
Several mathematical or statistical and artificial intelligence models were developed to compare egg production forecasts in commercial layers. Initial data for these models were collected from a comparative layer trial on commercial strains conducted at the Poultry Research Farms, Auburn University. Simulated data were produced to represent new scenarios by using means and SD of egg production of the 22 commercial strains. From the simulated data, random examples were generated for neural network training and testing for the weekly egg production prediction from wk 22 to 36. Three neural network architectures-back-propagation-3, Ward-5, and the general regression neural network-were compared for their efficiency to forecast egg production, along with other traditional models. The general regression neural network gave the best-fitting line, which almost overlapped with the commercial egg production data, with an R(2) of 0.71. The general regression neural network-predicted curve was compared with original egg production data, the average curves of white-shelled and brown-shelled strains, linear regression predictions, and the Gompertz nonlinear model. The general regression neural network was superior in all these comparisons and may be the model of choice if the initial overprediction is managed efficiently. In general, neural network models are efficient, are easy to use, require fewer data, and are practical under farm management conditions to forecast egg production. 相似文献
96.
John M. MacGregor John E. Rush Nancy J. Laste Rebecca L. Malakoff Suzanne M. Cunningham Natalie Aronow Daniel J. Hall Justin Williams Lori L. Price 《Journal of Veterinary Cardiology》2011,13(4):251-260
Hypothesis/ObjectivesTo describe the therapeutic use of pimobendan in cats, describe the patient population to which it was administered, document potential side effects and report the clinical course following administration of pimobendan in conjunction with standard heart failure therapy. It is hypothesized that cats with advanced heart disease including congestive heart failure from a variety of causes will tolerate pimobendan with a minimum of side effects when used in treatment in conjunction with a variety of other medications.Animals, materials and methodsOne hundred and seventy client owned cats with naturally occurring heart disease, one hundred and sixty four of which had congestive heart failure. Medical records were reviewed and owners and referring veterinarians were contacted for follow-up data. Data collected included pimobendan dose, other medications administered concurrently, data collected at physical examination, presence or absence of heart failure, adverse effects, classification of heart disease, echocardiographic data and survival time. The data were analyzed for significance between the initial visit and any follow-up visits.ResultsAll cats were treated with pimobendan. The median pimobendan dose was 0.24 mg/kg q 12 h. Pimobendan was used in combination with multiple concurrent medications including angiotensin converting enzyme inhibitors, diuretics and anti-thrombotics. Five cats (3.0%) had potential side effects associated with pimobendan. One cat (0.6%) had presumed side effects severe enough to discontinue pimobendan use. Median survival time for 164 cats with congestive heart failure after initiation of pimobendan was 151 days (range 1–870).ConclusionPimobendan appears to be well tolerated in cats with advanced heart disease when used with a variety of concurrent medications. Randomized controlled studies need to be performed to accurately assess whether it is efficacious for treatment of congestive heart failure in cats. 相似文献
97.
Syed Jawad Ahmad Shah Shaukat Hussain Musharaf Ahmad Farhatullah Iftikhar Ali Muhammad Ibrahim 《Journal of General Plant Pathology》2011,77(3):174-177
Fifty wheat varieties along with Jupateco-73 and Morocco were studied for the expression of leaf tip necrosis (LTN), a trait
linked with the durable rust resistance gene pair Lr34/Yr18. LTN was frequent (i.e., ≥6) in nine replications of a field experiment over 3 years in 17 genotypes, and the varieties were
considered positive for LTN. In molecular analyses of these varieties, having relative severity values up to 78 for yellow
rust and 45 for leaf rust, the 150-bp Lr34/Yr18-linked allele was consistently amplified. Expression of LTN in six of nine replications is an appropriate threshold for predicting
the presence of Lr34/Yr18 gene pair, and genotypes can be selected using this trait. 相似文献
98.
Summary We examined the influence of a vesicular-arbuscular (VAM) fungus (Glomus pallidum Hall) on the competitive ability of introduced and native Bradyrhizobium strains to nodulate cowpeas [Vigna unguiculata (L) Walp]. Our experiments in non-sterilized soil revealed that in the presence of VAM fungus, introduced Bradyrhizobium spp. strains become more competitive than native rhizobia. For example, strain JRC29 occupied 59.2% of the total nodules when inoculated alone, but this figure increased to 71.2% when JRC29 was used in dual inoculations with VAM fungus. A similar pattern of enhanced competitiveness for nodule formation was observed with the two other strains in the presence of the VAM fungus. Our results suggest that the competitiveness of rhizobia can be enhanced by co-inoculating with a selected strain of a VAM fungus. 相似文献
99.
Seedcoats of 16 almond varieties were screened for flavonol glycosides by using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Flavonol glycosides were extracted by a simple methanolic extraction followed by a quick cleanup procedure with a Sep-Pak C(18) cartridge. Each of the 16 seedcoat samples exhibited a unique composition. Four flavonol glycosides, isorhamnetin rutinoside, isorhamnetin glucoside, kaempferol rutinoside, and kaempferol glucoside, were detected and quantified with use of rutin as an internal standard. Individual peak ratios were very consistent across triplicate analyses of all samples; the average standard deviation was 9%. In all almond varieties, isorhamnetin rutinoside was the most abundant flavonol glycoside, and the total content ranged from 75 to 250 microg/g. 相似文献
100.
Rashid Ahmad 《Water, air, and soil pollution》2005,163(1-4):169-183
Cr(III) ions sorption onto sawdust of spruce (Picea smithiana) has been studied thoroughly using radiotracer technique. Maximum sorption (94%) of Cr(III) ions (8.98×10?5 M) onto sorbent surface is achieved from deionized water in 20 min agitation time using 200 mg of sawdust. The sorption data followed the Freundlich, Dubinin-Radushkevich (D-R) and Langmuir isotherms. Freundlich constants l/n = 0.86 ± 0.07 and C e = 85.0 ± 25.8 mmole g?1 have been estimated. Sorption capacity, X m = 0.82± 0.3 mmole g?1, β = ?0.00356± 0.00017 kJ2 mole?2 and energy, E = 11.9± 0.3 kJ mole?1 have been evaluated using D-R isotherm. The Langmuir constants Q = 5.8± 0.2 μmole g?1 and b = (7.4± 0.5)×104 dm3 mole?1 have been calculated. The variation of sorption with temperature yields thermodynamic parameters Δ H = ?11.6± 0.3 kJ mole?1, Δ S = ?16.2± 0.9 J mole?1 K?1 and Δ G = ?6.8± 0.3 kJ mole?1 at 298 K. The negative value of enthalpy and free energy reflect the exothermic and spontaneous nature of sorption respectively. Among the anions studied oxalate, citrate, carbonate and borate have reduced the sorption. The cations Y(III), Ce(II) and Ca(II) suppressed sorption. The sawdust column can be used to separate Cr(III) ion from Cs(I), I(I),Tc (VII) and Se (IV). 相似文献