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91.
The biogeography of pungency in three species of wild chili in the chaco and surrounding highland habitats of southeastern Bolivia is described. We report that Capsicum chacoense, C. baccatum, and C. eximium are polymorphic for production of capsaicin and its analogs, such that completely pungent and completely nonpungent individuals co-occur in some populations. In C. chacoense, the density of plants and the proportion of pungent plants increased with elevation. Above 900 m, all individuals in all populations except two were pungent; nonpungent individuals in at least one of the two polymorphic populations were likely a result of spreading by humans. The occurrence of pungent and nonpungent individuals in three species of ancestral Capsicum and the geographic variation of pungency within species suggest that production of capsaicin and its analogs entails both costs and benefits, which shift from one locality to another. Determining the selection pressures behind such shifts is necessary to understand the evolution of pungency in chilies.  相似文献   
92.
提出了一种应用反应精馏隔壁塔把乙酸甲酯废液处理成乙酸正丁酯的新工艺流程,即采用反应精馏隔壁塔替代常规流程中的反应精馏塔及甲醇回收塔。利用Aspen Plus模拟软件对反应精馏隔壁塔及常规流程进行了模拟,考察了进料位置、反应段位置及高度、耦合位置等结构参数对反应精馏隔壁塔的影响,并在保证产品纯度的前提下对反应精馏隔壁塔进行了最优化分析。分析结果显示反应精馏隔壁塔可以节能17.34%,并能有效降低设备投资费用和操作费用。  相似文献   
93.
Book reviews     
Landscape Transformed

London, Academy Editions, 1996, 112 pp., no price given, ISBN 1-85490-452-3

Sculpting with the Environment: a natural dialogue

Baile Oakes (Ed.)

New York, Van Nostrand Reinhold, 1995, ISBN 0-442-01642-5, 252 pp., £45.00, hb.

After the Ruins: restoring the countryside of Northern France after the Great War

Hugh Clout

Exeter, University of Exeter Press, 1996, ISBN 0-85989-491-6,332 pp., £35.

Environmental Aesthetics: ideas, politics and planning

J. Douglas Porteous

London and New York, Routledge, 1996, ISBN 0-415-13769-1, 20 pp., £15.99.

Countryside Survey 1990 Main Report

C.J. Barr, R.G.H. Bunce, R.T. Clarke, R.M. Fuller, M.T. Furse, M.K. Gillespie, G.B. Groom, C.J. Hallam, M. Hornung, D.C. Howard & M.J. Ness

London, Department of the Environment, 1993, 174 pp., £12.00 (available from DoE Publications Sales Unit, Block 3, Spur 2, Government Buildings, Lime Grove, Eastcote, HA4 8SE)

World of Environmental Design, Volume 1: Urban Spaces I (Streets and Squares)

Francisco Asenio Cerver

Barcelona, Arco Editorial, 1995, 255 pp., US$75 (per volume) ISBN 84-8185-004-7 (complete work), ISBN 84-8185-005-5 (Volume 1)

'The Remains of Distant Times': archaeology and the National Trust

David Morgan Evans, Peter Salway & David Thackray (Eds)

Woodbridge, Suffolk, The Boydell Press, 1996, ISBN 0-85115-671-1, hb, 235 pp., £29.50

Apostle of Taste: Andrew Jackson Downing 1815-1852

D. Schuyler

Baltimore, fohns Hopkins University Press, 1996, ISBN 0-8018-5229-3, $35.95  相似文献   
94.
1,3,5,5-Tetranitrohexahydropyrimidine, (1), was synthesized by the oxidative nitrolysis of 1,3-diisopropyl-5,5-dinitrohexahydropyrimidine, (2), with 90% nitric acid. The course of the reaction was influenced by both the n-alkyl substituents and the nitrolyzing medium. Compound 1 was synthesized by nitrolysis of N,N-diisopropyl or dicyclohexyl substituents, while dimethyl, diethyl, or other di-n-alkyl substituents yielded ring-cleaved products 3 and/or 4. Similar effects were observed by varying the nitric acid concentration. The formation of nitramine products, rather than nitrosamine or alkyl amide products that generally result from tertiary amine nitrolysis, is attributed to conformational changes in a postulated nitronium ion-amine complex intermediate.  相似文献   
95.
The tear film is a multi-layer fluid that covers the corneal and conjunctival epithelia of the eye and provides lubrication, nutrients, and protection from the outside environment. Tear fluid contains a high concentration of proteins and has thus been recognized as a potential source of biomarkers for ocular disorders due to its proximity to disease sites on the ocular surface and the non-invasive nature of its collection. This is particularly true in the case of dry eye disease, which directly impacts the tear film and its components. Proteomic analysis of tear fluid is challenging mainly due to the wide dynamic range of proteins and the small sample volumes. However, recent advancements in mass spectrometry have revolutionized the field of proteomics enabling unprecedented depth, speed, and accuracy, even with small sample volumes. In this study using the Orbitrap Fusion Tribrid mass spectrometer, we compared four different mass spectrometry workflows for the proteomic analysis of tear fluid collected via Schirmer strips. We were able to establish a method of in-strip protein digestion that identified >3000 proteins in human tear samples from 11 healthy subjects. Our method offers a significant improvement in the number of proteins identified compared to previously reported methods without pooling samples.  相似文献   
96.
Gliomas represent a wide spectrum of brain tumors characterized by their high invasiveness, resistance to chemoradiotherapy, and both intratumoral and intertumoral heterogeneity. Recent advances in transomics studies revealed that enormous abnormalities exist in different biological layers of glioma cells, which include genetic/epigenetic alterations, RNA expressions, protein expression/modifications, and metabolic pathways, which provide opportunities for development of novel targeted therapeutic agents for gliomas. Metabolic reprogramming is one of the hallmarks of cancer cells, as well as one of the oldest fields in cancer biology research. Altered cancer cell metabolism not only provides energy and metabolites to support tumor growth, but also mediates the resistance of tumor cells to antitumor therapies. The interactions between cancer metabolism and DNA repair pathways, and the enhancement of radiotherapy sensitivity and assessment of radiation response by modulation of glioma metabolism are discussed herein.  相似文献   
97.
This publication continues previously published work from the authors which evaluates the storage potential of poultry fat for its use as an unmodified biofuel in heat and steam generating systems [1]. The previous work examined the physical properties of these fats while this study is concerned with chemical properties. In this study poultry fat (biofuel) and its 20%, 40%, 60% and 80% mixtures with #2 pump diesel fuel were stored for 1 year at bench scale (1L) under controlled laboratory conditions at 4, 38, 54.4 °C and at 22 °C. One hundred percent of poultry fat was studied under these same conditions with and without an antioxidant additive. Twenty and eighty percent of poultry fat mixtures were also stored at pilot scale (250 gallons) under outdoor, ambient conditions. Chemical properties relevant to the use of these mixtures as a biofuel for industrial boilers were studied and tracked. These properties include Energy Values (BTU), Ultimate Analysis (carbon, hydrogen, oxygen, ash, nitrogen, and sulfur), moisture, impurities, unsaponafiables (MIU), and Free Fatty Acid Content. Energy content of the biofuel samples dropped over the course of the study with untreated biofuel losing 18.9% of its BTU value over the course of a year. Ultimate analyses showed an overall increase in carbon composition and a decrease in oxygen content. Hydrogen levels increased in most treatments as did overall ash and sulfur percent composition. MIU values increased, this overall increase was attributable to variable increases in insolubles and unsaponifiables. Free fatty acid levels increased in all treatments. Most of the chemical changes observed in this study were reduced by the addition of antioxidant to 100% biofuel.  相似文献   
98.
99.
While previous research on deterioration has focused on identifying individuals at risk for negative outcomes, little is known about the nature or pattern by which deterioration occurs. The problem of deterioration is especially salient in training clinics; a setting in which higher deterioration rates have been reported. Two studies were designed to test the applicability of the phase model to deterioration in a training clinic and to replicate the model with a training clinic referral-base sample. In Study 1, the course of therapy was monitored for 135 clients. For the 38 clients who deteriorated during therapy, a model where increased symptoms (demediation) reliably preceded both decreased functioning (dehabilitation) and decreased well-being (demoralization) was found. In Study 2, the same three phases were prospectively monitored for 914 undergraduate students on a weekly basis throughout a single semester. For the 158 individuals who deteriorated during this time, a model where demediation reliably preceded dehabilitation, which preceded demoralization was found. These results have clinical implications for the use of tailored intervention strategies focusing on the deterioration phases. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
100.
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