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41.
Kwiatkowska Marta Norman Gethin Parker David Santos Gabriel 《Formal Methods in System Design》2021,58(1-2):188-250
Formal Methods in System Design - Automated verification techniques for stochastic games allow formal reasoning about systems that feature competitive or collaborative behaviour among rational... 相似文献
42.
Norman Myers 《The Annals of Regional Science》1987,21(3):33-43
Much economic activity depends on the environmentalresource base (soils, water, vegetation, climate) that ultimately underpins virtually all human endeavor. This environmental-resource support is obviously important for agriculture, forestry, fisheries and hydropower generation. It is less obviously important for public health: without regular supplies of domestic-household water with sufficient quantity and quality, the risk of sanitation-disease increases. Much the same applies, through indirect linkages, to such further economic sectors as communications and education.These considerations are especially significant for developing countries. A greater share of their economies is usually dependent on the environmental-resource base than is the case with developed-world economies; and at the same time, the resource base, being generally tropical in location, is more fragile and hence susceptible to depletion than is the case with temperate-zone countries. Thus there is a premium on safeguarding the environmental-resource base as an integral part of those processes known as sustainable development.This is a revised and expanded version of a paper prepared for a Seminar on Land and Water Management, Economic Development Institute, The World Bank, November 10–21, 1986. The author is a consultant in Environment and Development, Upper Meadow, Old Road, Headington, Oxford, United Kingdom. The views expressed in this paper are those of the author, and should not be attributed to the World Bank, to its affiliated organizations or to any individual acting on their behalf. 相似文献
43.
Anna Kutschenko Selma Staege Karen Grütz Hannes Glaß Norman Kalmbach Thomas Gschwendtberger Lisa M. Henkel Johanne Heine Anne Grünewald Andreas Hermann Philip Seibler Florian Wegner 《International journal of molecular sciences》2021,22(7)
Myoclonus-dystonia (DYT-SGCE, formerly DYT11) is characterized by alcohol-sensitive, myoclonic-like appearance of fast dystonic movements. It is caused by mutations in the SGCE gene encoding ε-sarcoglycan leading to a dysfunction of this transmembrane protein, alterations in the cerebello-thalamic pathway and impaired striatal plasticity. To elucidate underlying pathogenic mechanisms, we investigated induced pluripotent stem cell (iPSC)-derived striatal medium spiny neurons (MSNs) from two myoclonus-dystonia patients carrying a heterozygous mutation in the SGCE gene (c.298T>G and c.304C>T with protein changes W100G and R102X) in comparison to two matched healthy control lines. Calcium imaging showed significantly elevated basal intracellular Ca2+ content and lower frequency of spontaneous Ca2+ signals in SGCE MSNs. Blocking of voltage-gated Ca2+ channels by verapamil was less efficient in suppressing KCl-induced Ca2+ peaks of SGCE MSNs. Ca2+ amplitudes upon glycine and acetylcholine applications were increased in SGCE MSNs, but not after GABA or glutamate applications. Expression of voltage-gated Ca2+ channels and most ionotropic receptor subunits was not altered. SGCE MSNs showed significantly reduced GABAergic synaptic density. Whole-cell patch-clamp recordings displayed elevated amplitudes of miniature postsynaptic currents and action potentials in SGCE MSNs. Our data contribute to a better understanding of the pathophysiology and the development of novel therapeutic strategies for myoclonus-dystonia. 相似文献
44.
The effect of dietary n−3 FA deficiency on bone tissue FA composition was evaluated in growing rats. Two mixtures combining
hydrogenated coconut oil with safflower oil served as the n−3-deficient dietary treatments and provided two levels of linoleic
acid (LA). The n−3 treatments were formulated with added α-linolenic acid (LNA) from flaxseed oil (diet LNA) or LNA plus DHA,
and both were balanced for LA. This study showed that bone is sensitive to changes in dietary n−3 FA and that DHA is more
effective than LNA in maintaining DHA levels in these tissues. 相似文献
45.
采用人胎盘血为原料,利用Sephadex G-200,DEAE-Sephadex A-50层析,Sepharose 4B反相免疫亲和层析技术,获得妊娠相关血浆蛋白A(PAPP-A)纯品,经8.0%聚丙烯酰胺凝胶电泳、免疫电泳、双向免疫扩散证明,所提取的PAPP-A纯品为单一成分。免疫家兔获得抗血清,其效价在1:16以上。 相似文献
46.
Chlorination of a low molecular weight polystyrene in the α position was studied by following changes in the infrared spectrum, glass transition temperature, and molecular weights of the polymer. The logarithm of the absorbance ratio at 2920 and 1500 cm?1 as a function of mole per cent chlorination was linear. The glass transition temperatures, determined by use of a differential scanning calorimeter (DSC), were found to obey an equation developed by Dyvik for copolymers. The molecular weight of the chlorinated polystyrene decreased as a function of chlorination. 相似文献
47.
Lynnette S. Walsh Hentges Donald C. Beitz Norman L. Jacobson A. Dare McGilliard Jeffrey J. Veenhuizen 《Lipids》1985,20(11):735-742
In a 2×2 factorial arrangement, miniature pigs were fed four diets containing vegetable protein/fat (soybean) and animal protein
(egg white)/fat (beef tallow) to demonstrate the effects of protein and fat source on total plasma cholesterol, lipoprotein
distribution, low density lipoprotein (LDL) composition, and plasma clearance of LDL-cholesterol and protein. Beef tallow
consumption resulted in greater plasma cholesterol concentration, decreased LDL-cholesterol concentration, and a lower LDL-cholesterol
to LDL-protein ratio than did consumption of soybean oil. High density lipoprotein (HDL)-cholesterol concentration was increased
by beef tallow consumption. Cholesterol percentage by weight in LDL was significantly greater in pigs consuming soybean oil
than those consuming beef tallow. Percentages by weight of protein, triglyceride and phospholipid in LDL were not significantly
different in any group. Dietary protein source had no significant effect on total plasma cholesterol concentration, lipoprotein
concentration or LDL composition. Egg white consumption decreased fractional catabolic rate and irreversible loss of LDL-cholesterol
and LDL-protein when compared with consumption of soy protein. Dietary fat source had no consistent effect on LDL clearance
from plasma. Dietary fat and protein seemed to influence lipoprotein metabolism by different mechanisms. Fat source altered
lipoprotein concentration and LDL composition, whereas protein source affected the removal rate of LDL from plasma.
Data taken from a dissertation submitted to Iowa State University by L. S. Walsh Hentges as partial fulfillment of the requirements
for the Ph.D. degree. A preliminary paper, was presented at the meeting of the American Oil Chemists' Society in Dallas, Texas,
May, 1984. 相似文献
48.
Norman Bilow 《应用聚合物科学杂志》1968,12(1):175-190
A series of poly-secondary aromatic amines was prepared by the acid-catalyzed condensation of N-methylaniline with formaldehyde. These condensation products were evaluated as curing agents for a standard epoxy prepolymer, namely bis(2,3-epoxypropoxyphenyl)propane. Various molar ratios of N-methylaniline to formaldehyde were used to produce polyamine condensation products with varying degrees of polymerization. These molar ratios ranged from 1.60 to 1.30. Dielectric properties of the cured epoxy resins at temperatures above 100°C. were highly dependent upon these ratios. Lower-ratio condensation products produced resins with optimum dielectric properties at the higher temperature and also with good physical properties. 相似文献
49.
Norman S. Allen Kenneth O. Fatinikun A.Keith Davies Barry J. Parsons Glyn O. Phillips 《Dyes and Pigments》1981,2(3):219-229
The photofading of two anthraquinone dyes has been studied in aqueous solution using ultraviolet-visible absorption spectroscopy and flash photolysis. The influence of alcohol concentration, pH, atmosphere, photosensitisers and stabilisers have been examined and these lead to some important conclusions on the mechanism of dye fading. Essentially, the results indicate the photoexcited triplet state of the dye undergoes a process of either electron or hydrogen-atom abstraction depending on the nature of the environment. Other factors such as aggregation and singlet oxygen also appear to play an important role in solution photofading. The relevance of these results to photofading in a polymeric phase is discussed. 相似文献
50.
The enzyme which forms glucocerebroside, ceramide: UDP-glucose glucosyltransferase, is inactivated in vitro by a cationic
analog of cerebroside, 2-decanoylamino-3-morpholinopropiophenone. A study of the inhibitor using intraperitoneal injection
into young mice showed that the level of the enzyme activity in liver was appreciably lowered between 3 and 6 hr after injection.
The activity increased subsequently, overshooting the normal level within 24 hr by about 20%, then returning to normal within
the next 24 hr. Additional effects observed in liver were an increase in lipid content (primarily in the triglyceride fraction
and ceramides) and a decrease in the glucocerebroside level. Body temperature dropped rapidly. Markedly similar effects were
produced by injecting chlorpromazine, which was tried in order to reduce the hyperirritability and inhibitory effects on monoamine
oxidase previously demonstrated by the glucosyltransferase inhibitor. Chlorpromazine did indeed block the hyperirritability
and resulted in enhancement of the keto amine's effects on the enzyme and lipids. It is possible that the two drugs in combination
would be helpful in ameliorating the symptoms due to the cerebroside accumulation that occurs in Gaucher disease. Diazepam
also produced a reduced level of glucosyltransferase. A color reaction for chlorpromazine, possibly suitable for quantitative
determination in tissues, was accidentally discovered. 相似文献