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151.
`The aim of this analysis is to investigate the existence of the dual solutions for magnetohydrodynamic (MHD) flow of an upper-convected Maxwell (UCM) fluid over a porous shrinking wall. We have employed the Lie group analysis for the simplification of the nonlinear differential system and computed the absolute invariants explicitly. An efficient numerical technique namely the shooting method has been employed for the constructions of solutions. Dual solutions are computed for velocity profile of an upper-convected Maxwell (UCM) fluid flow. Plots reflecting the impact of dual solutions for the variations of Deborah number, Hartman number, wall mass transfer are presented and analyzed. Streamlines are also plotted for the wall mass transfer effects when suction and blowing situations are considered. 相似文献
152.
The attachments of the lateral and medial ends of the extensor retinaculum of the human wrist were observed in 52 human upper limbs (from 26 cadavers) by dissection. In all the specimens used in this study, the lateral end of the retinaculum was found to be attached to the distal part of the anterior border of the radius and its medial end was attached to the styloid process of the ulna, the pisiform and the triquetrum. 相似文献
153.
A J Ullah R I Murray P K Bhattacharyya G C Wagner I C Gunsalus 《The Journal of biological chemistry》1990,265(3):1345-1351
The cytochrome P-450 heme-thiolate monooxygenases that hydroxylate monoterpene hydrocarbon groups are effective models for the cytochrome P-450 family. We have purified and characterized the three proteins from a P-450-dependent linalool 8-methyl hydroxylase in Pseudomonas putida (incognita) strain PpG777. The proteins resemble the camphor 5-exohydroxylase components in chemical and physical properties; however, they show neither immunological cross-reactivity nor catalytic activity in heterogenous recombination. These two systems provide an excellent model to probe more deeply the heme-thiolate reaction center, molecular domains of substrate specificity, redox-pair interactions, and the regulation of the reaction cycle. 相似文献
154.
Purification and characterization of phytase from cotyledons of germinating soybean seeds 总被引:12,自引:0,他引:12
Soybean phytase (myo-inositol-hexakisphosphate phosphohydrolase; EC 3.1.3.8) was purified from 10-day-old germinating cotyledons using a four-step purification scheme. Phytase was separable from the major acid phosphatase present, and stained as a minor band of the three acid phosphatases detectable by activity staining after gel electrophoresis. The purified enzyme exhibited two closely migrating bands on sodium dodecyl sulfate-polyacrylamide gel electrophoresis of approximately 59 and 60 KDa. The molar extinction coefficient of the enzyme at 280 nm was estimated to be 7.5 X 10(4) M-1 cm-1. The isoelectric point of phytase, as judged by the elution profile on chromatofocusing, was about 5.5. The enzyme was totally absorbed to a Procion Red HE3B column and eluted as a single protein component at a salt concentration of 250-300 mM. The enzyme possessed a high affinity for phytic acid (apparent Km = 48 microM), and was strongly inhibited by phosphate (apparent Ki = 18 microM), vanadate, and fluoride. Characteristic of other plant phytases, the pH and temperature optima were 4.5-4.8 and 55 degrees C, respectively. 相似文献
155.
Rhizosphere‐associated Alcaligenes and Bacillus strains that induce resistance against blast and sheath blight diseases,enhance plant growth and improve mineral content in rice
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K.U. Kakar Z. Nawaz Z. Cui A.A. Almoneafy R. Ullah Q.‐Y. Shu 《Journal of applied microbiology》2018,124(3):779-796
156.
Ghulam Murtaza Shahid Mehmood Shahid Rasul Imran Murtaza Ehsan Ullah Khan 《Reports of Practical Oncology and Radiotherapy》2018,23(3):189-198
Aim
The aim of study was to evaluate the dosimetric effect of collimator-rotation on VMAT plan quality, when using limited aperture multileaf collimator of Elekta Beam Modulator? providing a maximum aperture of 21 cm × 16 cm.Background
The increased use of VMAT technique to deliver IMRT from conventional to very specialized treatments present a challenge in plan optimization. In this study VMAT plans were optimized for prostate and head and neck cancers using Elekta Beam-ModulatorTM, whereas previous studies were reported for conventional Linac aperture.Materials and methods
VMAT plans for nine of each prostate and head-and-neck cancer patients were produced using the 6 MV photon beam for Elekta-SynergyS® Linac using Pinnacle3 treatment planning system. Single arc, dual arc and two combined independent-single arcs were optimized for collimator angles (C) 0°, 90° and 0°–90° (0°–90°; i.e. the first-arc was assigned C0° and second-arc was assigned C90°). A treatment plan comparison was performed among C0°, C90° and C(0°–90°) for single-arc dual-arc and two independent-single-arcs VMAT techniques to evaluate the influence of extreme collimator rotations (C0° and 90°) on VMAT plan quality. Plan evaluation criteria included the target coverage, conformity index, homogeneity index and doses to organs at risk. A ‘two-sided student t-test’ (p ≤ 0.05) was used to determine if there was a significant difference in dose volume indices of plans.Results
For both prostate and head-and-neck, plan quality at collimator angles C0° and C(0°–90°) was clinically acceptable for all VMAT-techniques, except SA for head-and-neck. Poorer target coverage, higher normal tissue doses and significant p-values were observed for collimator angle 90° when compared with C0° and C(0°–90°).Conclusions
A collimator rotation of 0° provided significantly better target coverage and sparing of organs-at-risk than a collimator rotation of 90° for all VMAT techniques. 相似文献157.
Shahida Shaheen Rafiq Ahmad Hussani Mubarak Nosheen Mirza Malik Tahir Hayat 《International journal of phytoremediation》2018,20(11):1162-1167
The effects of cadmium stress (0, 25, 50, 75, and 100 mg/L) on morpho-physiological features and selected genes (carotenoid hydroxilase, amidase, GR, bHLH, NRAMP and YSL) expression were demonstrated in Arundo donax L. The plants were assessed for Cd uptake and its effects on chlorophyll and antioxidants after 30 days of exposure. The expression of genes conferring metal tolerance was evaluated after 10 days of Cd exposure. The results showed a maximum Cd uptake in roots (872 mg/kg) followed by stem (734 mg/kg) and leaves (298 mg/kg) at highest supplied Cd concentration. The Cd uptake reduced dry weight, Chla, Chlb, and total Chl contents of giant reed. The SOD, CAT, POD activities and MDA content increased at the maximum Cd concentration over control. The highest genes expression for carotenoid hydroxylase, glutathione reductase and amidase was observed in plants exposed to 100 mg/L. However, differential bHLH gene expression and slightly increased gene expression of NRAMP was noted for different Cd treatments. Amidase expressed under Cd stress which is pioneer report in A. donax. These results provided insights into the mechanisms of A. donax tolerance and survival under Cd Stress. 相似文献
158.
Kifayat Ullah Khan Maqarab Shah Habib Ahmad Shujaul Mulk Khan Inayat Ur Rahman Zafar Iqbal Raees Khan Elsayed Fathi Abd_Allah Abdulaziz Abdullah Alqarawi Abeer Hashem Abdullah Aldubise 《Saudi Journal of Biological Sciences》2018,25(2):326-331
In the study area, the traditional knowledge regarding the uses of local wild medicinal plants for the health care of human and domestic animals is totally in hold of old people. The young ones are unaware about such an indispensable practices. The objective of the current study was to transfer this sort of precious knowledge from old members of the community to young generations in documented form. 相似文献
159.
Ullah Habib Khan Adnan Daud Noman Muhammad Rehman Anees Ur 《Plasmonics (Norwell, Mass.)》2018,13(2):591-597
Plasmonics - We numerically analyzed a simple and novel design of multi-broadband plasmonic absorber which consists of a planar array of thin gold square ring structures on dielectric/metal... 相似文献
160.
Sajjad Ali Umar Zeb Wang Lei Haroon Khan Khurram Shehzad Hanif Khan Irfan Ullah 《农业工程》2018,38(5):329-333
Floristic inventory of village Sherpao, District Charsadda comprised of total 104 plant species belonging to 46 families and 95 genera. The leading families included Fabaceae, Asteraceae, Poaceae and contributed by 8 species one (7.69%).The most pre-dominant life form was therophytes having 35 species (33.65%). Most dominant habit of flora were herbs having 77 species (74%) followed by trees contributed by 18 species (17.30%) and shrubs having 9 species (8.65%). Leaf size spectra of the flora showed that the most dominant leaf size class were microphyll having 38 species (36.53%) followed by nanophyll contributed by 32 species (30.76%), mesophyll represented 22 species (21.15%) and leptophyll contributed by 12 species (11.53%). Based on habitat 77 species (74%) were xerophytic in nature followed by 14 species (13.46%) in wet condition and 13 species (12.5%) were present in both conditions. In 104 plant species 85 were non spiny and 19 were spiny. Plant growth and distribution are having strong correlation with environment. Therefore, it is important to understand the environmental aspects that affect plant growth and distribution. 相似文献