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71.
Maruyama N Mohamed Salleh MR Takahashi K Yagasaki K Goto H Hontani N Nakagawa S Utsumi S 《Journal of agricultural and food chemistry》2002,50(15):4323-4326
We purified four single molecular species of beta-conglycinin heterotrimers consisting of the alpha and beta subunits or the alpha' and beta subunits from mutant soybean cultivars lacking the alpha or alpha' subunit, respectively, and examined their structural features and physicochemical functions. The extent of the hydrophobicities of the heterotrimers was related to the number of the alpha or alpha' subunit. The thermal stabilities of the heterotrimers were mainly conferred by the subunit which had lower thermal stability. Solubilities at low ionic strength (mu = 0.08) of the heterotrimers containing the alpha or alpha' subunit were very similar to those of the alpha and alpha' homotrimers, respectively. Emulsifying abilities and heat-induced associations of the heterotrimers containing one beta subunit were similar to those of the alpha or alpha' homotrimer, whereas those of the heterotrimers containing two beta subunits were similar to those of the beta homotrimer. 相似文献
72.
Mohamed R. Lasheen Salwa A. Shehata Gamila H. Ali 《Water, air, and soil pollution》1990,50(1-2):19-30
The Algal Assay Procedure Bottle Test was used to investigate the effect of Cd, Cu, and Cr (VI) on the growth of Nile water algae. The results of this investigation indicated that Cd has slight inhibitory effects on algal growth at low concentration (0.05 mg L?1), while it was inhibiting algal growth at higher concentration (> 1.0 mg L?1). In contrast, Cu and Cr did not affect algal growth in all investigated concentrations. Combinations of Cd with Cu and Cr seemed to interact synergistically. The synergism between Cd and Cu was more pronounced than between Cd and Cr. Clear changes in the diversity and redundancy of algal structure took place after metal addition. The inhibitory effect of the studied metals was in the following order: Cd-Cu > Cd - Cr > Cd > Cu > Cr. 相似文献
73.
In an attempt to evaluate whether breeding and selection for high yielding capacity changed the P requirement of modem wheat cultivars. the response of two wheat cultivars to different levels of P supply was investigated. A traditional cultivar (‘Peragis’) and a modern spring-wheat cultivar (‘Cosir’) were cultivated in a C-loess low in available P and high in CaCO3 in 120 cm high PVC tubes. In addition and for comparison, nutrient solution experiments were also conducted. Shoot growth, root growth. P uptake. P translocation and P distribution within the shoot at different developmental stages were compared. The grain yield of the modern cultivar ‘Cosir’ was higher at limiting and non-limiting P supply and. therefore, this cultivar can be considered as more P-efficient than the traditional cultivar. Grain yield reduction at low P supply was mainly due to an inhibition of tillering and thus lower number of ears per plant, whereas the number of grains per ear was hardly affected. Reduced tillering at low P supply could not be related to P concentrations in the shoot meristematic tissues which were generally much higher than in other plant tissues and kept at an elevated level even at limiting P supply. Root branching (1st order laterals) was reduced at limiting P supply in ‘Cosir’ but not in ‘Peragis’ which, generally, had lower numbers of laterals at the beginning of tillering. From the results it can be concluded that the main factors contributing to the higher P efficiency of the modern cultivar ‘Cosir’ are (i) efficient use of assimilates for root-growth characteristics which enhance P acquisition: enhanced root branching and thus smaller mean root diameter and longer root hairs, (ii) an efficient P uptake system, (iii) efficient remobilization of P from vegetative plant organs to the grains, and most importantly (iv) lower P requirement for grain yield formation because of lower ear number per plant but higher grain number per ear. 相似文献
74.
75.
Sanloup C Schmidt BC Chamorro Perez EM Jambon A Gregoryanz E Mezouar M 《Science (New York, N.Y.)》2005,310(5751):1174-1177
The reactivity of xenon with terrestrial oxides was investigated by in situ synchrotron x-ray diffraction. At high temperature (T > 500 kelvin), some silicon was reduced, and the pressure stability of quartz was expanded, attesting to the substitution of some xenon for silicon. When the quartz was quenched, xenon diffused out and only a few weight percent remained trapped in samples. These results show that xenon can be covalently bonded to oxygen in quartz in the lower continental crust, providing an answer to the missing xenon problem; synthesis paths of rare gas compounds are also opened. 相似文献
76.
77.
El-Sherbeini M 《Science (New York, N.Y.)》2011,333(6050):1702-1703
78.
Kameshwari Pothukuchi Rayman Mohamed David A. Gebben 《Agriculture and Human Values》2008,25(3):319-332
This paper provides a conceptual framework to explain why disparities may exist in food safety code compliance by food stores
in different neighborhoods. Explanations include market dynamics, community characteristics, retailer attributes, inspector
characteristics, and enforcement approaches, and interactions among the factors. A preliminary and limited empirical test
of some of these relationships in Detroit, Michigan shows a higher rate of food safety violations by stores in poorer neighborhoods
and in neighborhoods with higher concentrations of African-American residents. Stores inspected by female inspectors also
scored higher numbers of critical violations, suggesting a need for greater examination of the social relations associated
with enforcement interactions in food safety studies.
Kameshwari Pothukuchi PhD, is Associate Professor of Urban Planning at Wayne State University. She conducts research on issues related to urban food security, including grocery stores, community gardens, and community and regional food planning. A policy guide on community and regional food planning, co-authored by her, was recently adopted by the American Planning Association (). Rayman Mohamed PhD, is Assistant Professor of Urban Planning at Wayne State University. He conducts research on land use and environmental planning. His recent articles examine decision making by developers, the economics of conservation subdivisions, and the relationship between sprawl and the costs of infrastructure. David A. Gebben is a graduate student of agricultural economics and a research assistant in the Global Urban Studies Program at Michigan State University. 相似文献
Kameshwari PothukuchiEmail: |
Kameshwari Pothukuchi PhD, is Associate Professor of Urban Planning at Wayne State University. She conducts research on issues related to urban food security, including grocery stores, community gardens, and community and regional food planning. A policy guide on community and regional food planning, co-authored by her, was recently adopted by the American Planning Association (). Rayman Mohamed PhD, is Assistant Professor of Urban Planning at Wayne State University. He conducts research on land use and environmental planning. His recent articles examine decision making by developers, the economics of conservation subdivisions, and the relationship between sprawl and the costs of infrastructure. David A. Gebben is a graduate student of agricultural economics and a research assistant in the Global Urban Studies Program at Michigan State University. 相似文献
79.
Cruz-Migoni A Hautbergue GM Artymiuk PJ Baker PJ Bokori-Brown M Chang CT Dickman MJ Essex-Lopresti A Harding SV Mahadi NM Marshall LE Mobbs GW Mohamed R Nathan S Ngugi SA Ong C Ooi WF Partridge LJ Phillips HL Raih MF Ruzheinikov S Sarkar-Tyson M Sedelnikova SE Smither SJ Tan P Titball RW Wilson SA Rice DW 《Science (New York, N.Y.)》2011,334(6057):821-824
The structure of BPSL1549, a protein of unknown function from Burkholderia pseudomallei, reveals a similarity to Escherichia coli cytotoxic necrotizing factor 1. We found that BPSL1549 acted as a potent cytotoxin against eukaryotic cells and was lethal when administered to mice. Expression levels of bpsl1549 correlate with conditions expected to promote or suppress pathogenicity. BPSL1549 promotes deamidation of glutamine-339 of the translation initiation factor eIF4A, abolishing its helicase activity and inhibiting translation. We propose to name BPSL1549 Burkholderia lethal factor 1. 相似文献
80.
The present study was to assess informativeness and efficiency of three different molecular markers for genetic diversity among 24 Citrus and its relative species. Sixty one SSR, 33 SRAP and 24 CAPS-SNP markers were used to evaluate the level of polymorphism and discriminating capacity. A total of 596, 656 and 135 polymorphic amplicons were observed in SSR, SRAP and CAPS-SNP markers with average polymorphism information content (PIC) of 0.97, 0.98 and 0.89, respectively. High levels of polymorphism were recorded for SSR and SRAP compared with CAPS-SNP markers. The highest correlations (r = 0.930) were obtained between SSR and SRAP markers, whereas SSR and CAPS-SNP were poorly correlated (r = 0.833). Cluster analysis was performed to construct dendrograms using UPGMA. And the dendrogram from SSR data was most congruent with the general dendrogram. These findings provide basis for future efficient use of these molecular markers in the genetic analysis of Citrus and its relatives. 相似文献