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81.
Pithouse Architecture and the Economics of Household Formation in the Prehistoric American Southwest
W. H. Wills 《Human ecology: an interdisciplinary journal》2001,29(4):477-500
Changes in prehistoric Southwestern architecture have been interpreted as the result of increasing dependence on agriculture through time which promoted greater sedentism. Recent archaeological research has produced data that point to changes in labor organization rather than agricultural productivity as the factors that most likely favored new forms of domestic architecture. In fact, some of the most striking temporal shifts in residential architecture may have been associated with declining agricultural productivity. 相似文献
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Quantitative study of aluminum binding to human serum albumin and transferrin by a chelex competitive binding assay 总被引:2,自引:0,他引:2
R L Bertholf M R Wills J Savory 《Biochemical and biophysical research communications》1984,125(3):1020-1024
Binding of aluminum to human serum albumin and transferrin was investigated using a competitive binding assay incorporating a cation exchange resin, chelex. Both albumin and transferrin were found to produce linear Scatchard plots of aluminum binding data over the aluminum and protein concentration ranges found in humans. Binding constants measured for albumin and transferrin were 1.96 and 0.515 microM, respectively. 相似文献
84.
While supertrees have been built for many vertebrate groups (notably birds, mammals and dinosaurs), invertebrates have attracted relatively little attention. The paucity of supertrees of arthropods is particularly surprising given their economic and ecological importance, as well as their overwhelming contribution to biodiversity. The absence of comprehensive archives of machine-readable source trees, coupled with the need for software implementing repeatable protocols for managing them, has undoubtedly impeded progress. Here we present a supertree of Achelata (spiny, slipper and coral lobsters) as a proof of concept, constructed using new supertree specific software (the Supertree Toolkit; STK) and following a published protocol. We also introduce a new resource for archiving and managing published source trees. Our supertree of Achelata is synthesised from morphological and molecular source trees, and represents the most complete species-level tree of the group to date. Our findings are consistent with recent taxonomic treatments, confirming the validity of just two families: Palinuridae and Scyllaridae; Synaxidae were resolved within Palinuridae. Monophyletic Silentes and Stridentes lineages are recovered within Palinuridae, and all sub-families within Scyllaridae are found to be monophyletic with the exception of Ibacinae. We demonstrate the feasibility of building larger supertrees of arthropods, with the ultimate objective of building a complete species-level phylogeny for the entire phylum using a divide and conquer strategy. 相似文献
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Siobhán S. Wills Colin L. Raston Keith A. Stubbs 《Bioorganic & medicinal chemistry letters》2018,28(23-24):3748-3751
A simple synthesis, which utilizes a thin film microfluidic reactor for a problematic step, of a potent inhibitor of α-N-acetylhexosaminidases, DGJNAc, has been developed. 相似文献
89.
Kinetics of Initiation of Germination of Bacillus pumilus Spores by Hydrostatic Pressure 总被引:2,自引:2,他引:0 下载免费PDF全文
The kinetics of initiation of germination and inactivation by hydrostatic pressure of phosphate-buffered Bacillus pumilus spores is shown to be a consecutive first-order process at 25 C. The effect of increasing pressure at constant temperature was studied, and rate constants were derived by using the criteria of heat resistance, refractility, and stainability. The calculated volume change of activation (DeltaVdouble dagger) was -139 +/- 6 cm(3)/mole for loss of heat resistance, -158 +/- 8 cm(3)/mole for the loss of refractility, and -153 +/- 4 cm(3)/mole for the change in permeability to dilute stains for the pressure range 800 to 1,010 atm at 25 C. It is suggested that the spore exists as a Donnan phase and that pressure triggers germination by influencing the equilibrium. 相似文献
90.
Effects of lipid peroxidation on membrane-bound enzymes of the endoplasmic reticulum 总被引:3,自引:2,他引:1 下载免费PDF全文
E. D. Wills 《The Biochemical journal》1971,123(5):983-991
1. Induction of the formation of lipid peroxide in suspensions of liver microsomal preparations by incubation with ascorbate or NADPH, or by treatment with ionizing radiation, leads to a marked decrease of the activity of glucose 6-phosphatase. 2. The effect of peroxidation can be imitated by treating microsomal suspensions with detergents such as deoxycholate or with phospholipases. 3. The substrate, glucose 6-phosphate, protects the glucose 6-phosphatase activity of microsomal preparations against peroxidation or detergents. 4. The loss of glucose 6-phosphatase activity is not due to the formation of hydroperoxide or formation of malonaldehyde or other breakdown products of peroxidation, all of which are not toxic to the enzyme. 5. All experiments lead to the conclusion that the loss of activity of glucose 6-phosphatase resulting from peroxidation is a consequence of loss of membrane structure essential for the activity of the enzyme. 6. In addition to glucose 6-phosphatase, oxidative demethylation of aminopyrine or p-chloro-N-methylaniline, hydroxylation of aniline, NADPH oxidation and menadione-dependent NADPH oxidation are also strongly inhibited by peroxidation. However, another group of enzymes separated with the microsomal fraction, including NAD+/NADP+ glycohydrolase, adenosine triphosphatase, esterase and NADH–cytochrome c reductase are not inactivated by peroxidation. This group is not readily inactivated by treatment with detergents. 7. Lipid peroxidation, by controlling membrane integrity, may exert a regulating effect on the oxidative metabolism and carbohydrate metabolism of the endoplasmic reticulum in vivo. 相似文献