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31.
Abdul ghafoor Muhammad N Riaz Aamer B Zahur Nasir Abbas Muhammad Yousaf Abdullah Shah Rafaqat Ishaq Muhammad Suleman 《International Journal of Dairy Technology》2015,68(1):105-110
Kappa‐casein (κ‐CN) is the subtype of casein protein, an important constituent of bovine milk protein. The current study was undertaken to investigate the genetic polymorphism in κ‐CN gene of Nili‐ravi buffalo, Achai and Sahiwal cattle of Pakistan using polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP) technique. The Nili‐ravi buffalo was found to be monomorphic (genotype BB only) for κ‐CN gene. Achai cattle were polymorphic for κ‐CN (having three genotypes AA, AB and BB) with a frequency of 0.70, 0.18 and 0.12, respectively, while in Sahiwal cattle, both the genotypes AA and AB were found with genotypic frequencies of 0.92 and 0.08, respectively. The presence of genotype BB in Achai cattle is surprising as it is absent in most of the cattle breeds worldwide. 相似文献
32.
Murtaza Ijaz Rabia Afza Muhammad Zafar Muhammad Hamayun Shujaul Mullk Khan Zeeshan Ahmad Mushtaq Ahmad Sumera Afzal Khan Raheem Shah Muhammad Yahya 《Microscopy research and technique》2022,85(2):755-766
Rusts comprises the largest natural group of plant pathogens including approximately 8% of all described Fungi. Rust fungi are extremely plant pathogens responsible for great losses to agriculture productivity. Rust species belong to several genera among which more than half are Puccinia species. In Pakistan, rust causes severe damage to agriculture crops. Current study was carried out to identify and characterize different rust species common in the research area through microscopy and Scanning electron microscopy (SEM) in Khyber Pakhtunkhwa, Pakistan. Morpho-anatomical investigation of each collected rust species was carried out using different standard protocols. The dimensions of spores were measured and snapped under a stereomicroscope. SEM was used to examine the shape, size, and ornamentation of the spores of each rust fungus. Results revealed documentation of seven rust fungi, that is, Melampsora euphorbiae, Phragmidium barclayi, Puccinia nepalensis, P. exhausta, P. menthae, Uromyces capitatus, and Uromyces decorates belong to four different genera, were recorded. SEM revealed that spermogonia and Aecia were missing in most of the rust fungus studied. Uredinia was found in a scattered, irregular, lengthy, and epidermis-enclosed form. Urediniospores were found to be ovulating, elongated, echinulate, globose to sub-globose, ellipsoid to ovoid, and globose to sub-globose. Telia was found as sub-epidermal, amphigenous, dispersed, minute, and spherical cells. Teliospores ranged in form from cylindrical to oblong. The germ pores were detected in both apical (top cell) and basal (bottom cell) idiosyncratic and pedicel-attached cells. The techniques used in the current investigation will aid mycologists in rust identification and microscopic characterization. 相似文献
33.
This paper describes an empirical study undertaken to investigate the quantitative aspects of the phenomenon of requirements elaboration which deals with transformation of high-level goals into low-level requirements. Prior knowledge of the magnitude of requirements elaboration is instrumental in developing early estimates of a project’s cost and schedule. This study examines the data on two different types of goals and requirements - capability and level of service (LOS) - of 20 real-client, graduate-student, team projects done at USC. Metrics for data collection and analyses are described along with the utility of results they produce. Besides revealing a marked difference between the elaboration of capability goals and the elaboration of LOS goals, these results provide some initial relationships between the nature of projects and their ratios of elaboration of capability goals into capability or functional requirements. 相似文献
34.
35.
Adaptive automated planning systems that can, over time, improve the quality of plans they produce are a promising prospect. The first part of the article discusses the issues involved in designing quality improving learning for planning systems and reviews recent work on learning to improve plan quality. The second part describes our work on the Performance Improving Planning (PIP) System. The heart of PIP is an analytic technique that compares two planning episodes for solving a planning problem that led to two different quality solutions—a higher-quality solution and a lower quality solution—and identifies the critical differences that were responsible for the resulting differences in the quality of the completed plans. We compare the effectiveness of two different ways of storing and applying the knowledge learned from this analysis—as search-control rules and as rewrite rules. The results show that the search-control rules are more effective in improving plan quality. Further analysis of PIP-search-control—the version of PIP that stores the learned knowledge as search-control rules—shows that it is an effective technique for improving plan quality in a variety of situations. 相似文献
36.
Wei Gao Mohammad Reza Farahani Muhammad K. Jamil Muhammad K. Siddiqui Hafiz Muhammad Afzal Siddiqui Muhammad Imran 《Petroleum Science and Technology》2017,35(2):183-189
Different approaches have been used to convert the waste materials into a clean syngas or other chemicals such as methanol. Among them, pyrolysis is a good candidate to produce the synthesis gas and volatile matters for industrial and refinery applications. In this work, we studied the kinetic and chemical behavior of three Iranian waste oils through a kinetic model and an experimental study. The experiments carried out in a micro-FB reactor, which is a good option for low emissions. Results showed that the reaction temperature and reaction rate are two of the most important factors for maximum conversion level of fuel. Results also showed an optimum value for reaction rate. The modeling results validated against the experimental measurements and found to be in good agreements. 相似文献
37.
Design considerations for an automotive magnetorheological brake 总被引:2,自引:0,他引:2
In this paper, design considerations for building an automotive magnetorheological (MR) brake are discussed. The proposed brake consists of multiple rotating disks immersed in a MR fluid and an enclosed electromagnet. When current is applied to the electromagnet, the MR fluid solidifies as its yield stress varies as a function of the magnetic field applied. This controllable yield stress produces shear friction on the rotating disks, generating the braking torque. In this work, practical design criteria such as material selection, sealing, working surface area, viscous torque generation, applied current density, and MR fluid selection are considered to select a basic automotive MR brake configuration. Then, a finite element analysis is performed to analyze the resulting magnetic circuit and heat distribution within the MR brake configuration. This is followed by a multidisciplinary design optimization (MDO) procedure to obtain optimal design parameters that can generate the maximum braking torque in the brake. A prototype MR brake is then built and tested and the experimental results show a good correlation with the finite element simulation predictions. However, the braking torque generated is still far less than that of a conventional hydraulic brake, which indicates that a radical change in the basic brake configuration is required to build a feasible automotive MR brake. 相似文献
38.
Copper tellurite glasses containing NiO, CoO and Lu2O3 were prepared by the melt-quenching technique. The composition used was 65TeO2-(35-x)CuO-xTMO (mol%), where TMO indicates NiO, CoO, Lu2O3, and for NiO- and CoO-doped glasses,x has the values 0, 0.5, 1 to 4, and for Lu2O3 doped glasses x=0 to 4. Electron spin resonance (ESR) spectra of all glasses were recorded at room temperature. The results on glasses doped with NiO, CoO and Lu2O3 are discussed in terms of oxidation-reduction, cross-relaxation and interelectronic repulsion processes, respectively. Cobalt oxide is found to be more effective in relaxing the ESR spectrum than nickel and lutetium oxides when substituted in copper tellurite glasses. 相似文献
39.
Benefits analysis of US Federal government research, development, demonstration, and deployment (RD3) programmes for renewable energy (RE) technology improvement typically employs a deterministic forecast of the cost and performance of renewable and non-renewable fuels. The benefits estimate for the programme derives from the difference between two forecasts, with and without the RD3 programme in place. Three deficiencies of this approach are that it ignores: (1) uncertainty in the cost of non-renewable energy (NRE); (2) the possibility of adjustment to the RD3 effort commensurate with the evolving state of the world; and (3) the underlying technical risk associated with RD3. In this paper, an intuitive approach to determining the option value of RE RD3 is developed. This approach seeks to tackle the first two deficiencies noted above by providing an estimate via a compound real option of an RE RD3 programme in a future with uncertain NRE costs. A binomial lattice reveals the economic intuition underlying the decision-making process, while a numerical example illustrates the option components embedded in a simplified representation of current US Federal RE RD3. 相似文献
40.
1. The roles of both Ca2+ and adenosine 3':5'-cyclic monophosphate (cyclic AMP) in carbachol and K(+)-stimulated [3H]-noradrenaline release from SH-SY5Y human neuroblastoma cells were examined. 2. Both carbachol and K+ caused a time- and dose-related stimulation of [3H]-noradrenaline release. The release event in perfused cells was monophasic. Half-maximum stimulation measured in statically incubated (3 min) cells was 38 +/- 4 microM and 63 +/- 4 mM respectively. K+ (100 mM, added)-evoked release was greater than that produced by carbachol (1 mM). 3. Both carbachol and K+ caused a time- and dose (measured at 3 min)-related stimulation of cyclic AMP formation with half-maximum stimulation occurring at 5 +/- 1 microM and 49 +/- 2 mM respectively. In contrast to its effects on release, carbachol produced a greater stimulation of cyclic AMP formation than K+. 4. K(+)-stimulated [3H]-noradrenaline release was entirely dependent on Ca2+ entry as 2.5 mM Ni2+ abolished release. However, carbachol-evoked (1 mM) release appeared to be unaffected by Ni2+ pretreatment. 5. These data suggest that in SH-SY5Y cells, elevated cyclic AMP levels are not directly involved in [3H]-noradrenaline release. In addition, carbachol-stimulated release is largely independent of extracellular Ca2+ possibly implying a role for intracellular stored Ca2+ in the release process. 相似文献