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硫酸传质衬砖塔的设计

硫酸工业 2015年第3期 23-27页

作者： c.guy cooper ANDRS MAHEcHA-BOTERO KAR TRENKEL KIM NIKOLAISEN ALFRED GUENKEL JOHN ORLANDO 茆卫兵 NORAM工程建设有限公司

主要探讨了硫酸干吸塔设计的制造材料、塔底结构、填料类型、分酸器类型、除雾器和衬砖,对合金塔和衬砖塔进行了对比。介绍了硫酸干吸塔的类型、确定酸塔直径需考虑的因素、填料高度的计算,以及酸塔的安装、更换和维护保养。

关键词：硫酸生产吸收干燥解吸硫酸塔衬砖

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Risk prediction of advanced colorectal neoplasia varies by race and neighbourhood socioeconomic status

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Family Medicine and community Health 2024年第S2期12卷 26-33页

作者： Xiangqing Sun Zhengyi chen Gregory S cooper Nathan A Berger claudia coulton Li Li Department of Family Medicine University of VirginiaCharlottesvilleVirginiaUSA Department of Population and Quantitative Health Sciences Case Western Reserve UniversityClevelandOhioUSA University Hospitals cleveland Medical center ClevelandOhioUSA case comprehensive cancer center ClevelandOhioUSA Jack Joseph and Morton Mandel School of Applied Social SciencesCase Western Reserve UniversityClevelandOhioUSA

Objective Neighbourhood deprivation increases the risk of colorectal neoplasia and contributes to racial disparities observed in this *** race-specific advanced colorectal neoplasia(AcN)prediction models that include neighbourhood socioeconomic status has the potential to improve the accuracy of *** The study includes 1457 European Americans(EAs)and 936 African Americans(AAs)aged 50–80 years undergoing screening ***-specific AcN risk prediction models were developed for EAs and AAs,*** Deprivation Index(ADI),derived from 17 variables of neighbourhood socioeconomic status,was evaluated by adding it to the AcN risk prediction *** accuracy was evaluated by concordance statistic(c-statistic)for discrimination and Hosmer-Lemeshow goodness-of-fit test for *** With fewer predictors,the EA-specific and AA-specific prediction models had better prediction accuracy in the corresponding race/ethnic subpopulation than the overall *** with the overall model which had poor calibration(P_(calibration)=0.053 in the whole population and P_(calibration)=0.011 in AAs),the EA model had c-statistic of 0.655(95%cI 0.594 to 0.717)and P_(calibration)=0.663;and the AA model had c-statistic of 0.637((95%cI 0.572 to 0.702)and P_(calibration)=*** was a significant predictor of AcN in EAs(OR=1.24((95%cI 1.03 to 1.50),P=0.029),but not in AAs(OR=1.07((95%cI 0.89 to 1.28),P=0.487).Adding ADI to the EA-specific AcN prediction model substantially improved AcN calibration accuracy of the prediction across area deprivation groups(P_(calibration)=0.924 with ADI vs P_(calibration)=0.140 without ADI)in *** Neighbourhood socioeconomic status is an important factor to consider in AcN risk prediction ***,non-race-specific prediction models have poor ***-specific prediction models incorporating neighbourhood socioeconomic factors are needed to improve AcN predicti

关键词： colorectal neoplasia prediction

choosing between a rock and a hard place： camouflage in the round-tailed horned lizard Phrynosoma modestum

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current Zoology 2012年第4期58卷 541-548页

作者： William E. cooper, Jr. Wade c. SHERBROOKE Department of Biology Indiana University Purdue University Fort Wayne Fort Wayne IN 46805 USA Southwestern Research Station American Museum of Natural History PO Box 16553 Portal AZ 85632 USA

The round-tailed homed lizard Phrynosoma modestum is cryptically colored and resembles a small stone when it draws legs close to its body and elevates its back. We investigated effectiveness of camouflage in P. modestum and its dependence on stones by placing a lizard in one of two microhabitats （uniform sand or sand with surface rocks approximately the same size as lizards）. An observer who knew which microhabitat contained the lizard was asked to locate the lizard visually. Latency to detec- tion was longer and probability of no detection within 60 s was higher for lizards on rock background than on bare sand. In arenas where lizards could choose to occupy rock or bare sand, much higher proportions selected rocky backgrounds throughout the day; at night all lizards slept among stones. A unique posture gives P modestum a rounded appearance similar to many natural stones. Lizards occasionally adopted the posture, but none did so in response to a nearby experimenter. Stimuli that elicit the posture are unknown. That P. modestum is better camouflaged among rocks than on bare sand and prefers to occupy rocky areas suggests that special resemblance to rocks （masquerade） enhances camouflage attributable to coloration and immobility.

关键词： Animal defense Background matching camouflage crypsis Masquerade Squamata

cannibalism in the pea aphid, Acyrthosiphon pisum

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Insect Science 2014年第6期21卷 750-758页

作者： Lucy c. cooper camille Desjonqueres Simon R. Leather Imperial college London Silwood Park Campus Buckhurst Road Ascot Berkshire SL5 7PY Department of crop and Environment Sciences Harper Adams University Edgmond Newport Shropshire TF10 8NB United Kingdom

Previous observations of cannibalism have been made in the aphid Acyrthosiphon pisum （L.）： this article seeks to quantify factors contributing to such be- haviors. We observed and quantified the responses of a number of clones and life stages to varying levels of starvation, in the form of increasingly desiccated Vicafaba L. plants （receiving 50, 25, or 10 mL every second day） or a complete absence of host plant. We found that, while the longest incidences of cannibalism are carried out by juveniles （F = 3.45, P = 0.019, df = 3） and targeted at adults, the starvation treatments had the most significant effect on the prevalence of cannibalism in mature A. pisum （F ---- 2.24, P = 0.025, df = 9）. Furthermore, there was no difference between the prevalence or dura- tion of cannibalistic activities within and between different clones （P 〉 0.05 in all cases）, though juveniles were more likely to target unrelated aphids （V = 6 112, P = 0.011）, and spent more time feeding on aphids from the same culture （V = 6 062, P = 0.018）.

关键词： Acyrthosiphon pisum Aphididae behavior cannibalism kin selection modularity

c. H. Pander＇s introduction to conodonts, 1856

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Episodes 2008年第4期31卷 429-432页

作者： Sweet W.c. cooper B.J. School of Earth Sciences The Ohio State University Columbus OH 43210 United States Primary Industries and Resources South Australia GPO Box 1671 Adelaide SA 5001 Australia

It is rare in the annals of science for a single publication to provide a definitive introduction to a previously unknown group of animals. Yet this was the case with the monograph that included the initial descriptions of an important, extinct group of fossil animals： the conodonts. The publication, by christian Heinrich Pander, appeared in St Petersburg in 1856. The volume of ninety-one pages, written in German and accompanied by seven beautifully executed plates, was issued by the Imperial Academy of Sciences as part of a series entitled Geognostische Beschreibung der Russisch-Baltischen Gouvernements.

关键词：动物科学动物化石牙形石科学研究

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The omentum

World Journal of Gastroenterology 2000年第2期6卷 169-176页

作者： cameron Platell Deborah cooper John M.Papadimitriou John c.Hall Department of Surgery the University of Western Australia Departments of Pathology the University of Western Australia

INTRODUcTIONThe word omentum derives from the ancientEgyptians who,when embalming human bodies,used to assess their'omens'by looking at thevariations in what we recognise today as ***(128-199 AD)thought that therole of the omentum was to warm the *** was on the basis of a gladiator who had anomental resection after a stab injury and sufferedgreatly from cold for the rest of his life.A

关键词： omentum peritonitis macrophage neutrophil lymphocytes mesothelium adhesions omentectomy

Non-Uniformity and Generalised Sacks Splitting

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Acta Mathematica Sinica,English Series 2002年第2期18卷 327-334页

作者： cooper S.Barry Department of Pure Mathematics School of Mathematics University of Leeds Leeds UK Institute of Software Chines Academy of Sciences Beijing P. R. China

We show that there do not exist computable fimetions f_1(e,i).f_2(e,i).g_1(e,i),g_2(e,i)such that for all e,i ∈ω, (1)(W_(f_1)(e,i)-W_(f_2)(e,i))≤T(W_e-W_1): (2)(W_(g_1)(e,i)-W_(g_2)(e,i))≤T(W_e-W_i): (3)(W_w-W_i)≤T(W_(f_1)(e,i)-W_(f_2)(e,i))⊕(W_(g_1)(e,i)-W_(g_2)(e,i)): (4)(W_e-W_i)T(W_(f_1)(e,i)-W_(f_2)(e,i))uuless(W_e-W_i)≤T:and (5)(W_e-W_i)T(E_(g_1)(e,i)-W_(g_2)(e,i))unless(W_w-W_i)≤T. It follows that the splitting theorems of Sacks and cooper cannot be combined uniformly.

关键词： computably enumerable(c.e.) Difference of computably enumerable sets(d.c.e.,or 2-c.e.) Turing degrees Splitting and nonsplitting

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Androgens and prostate disease

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Asian Journal of Andrology 2014年第2期16卷 248-255,I0009页

作者： Lori A cooper Stephanie T Page Departments of Medicine Division of Endocrinology and Metabolism University of Washington Seattle University of Washington and Harborview Medical center Seattle Washington USA.

A growing body of literature has established the anabolic benefits of testosterone （T） therapy in hypogonadal men. However, there remains a paucity of data regarding the risks of exogenous androgen use in older men and the potential for adverse effects on the prostate gland. Whether T therapy in older, hypogonadal men might worsen lower urinary tract symptoms or exacerbate, unmask, or even incite prostate cancer development has tempered enthusiasm for T therapy, while known prostatic disease has served as a relative contraindication to T therapy. Androgens are necessary for the development and maintenance of the prostate gland. However, epidemiologic studies do not consistently find a positive relationship between endogenous serum androgen concentrations and the risk of prostate disease. Recent data demonstrate that 5α-reductase inhibitors decrease the risk of low-grade prostate cancer, suggesting that modifying androgen metabolism may have beneficial effects on prostate health, yet similar reductions in high-grade disease have not been observed, thereby questioning the true clinical benefits of these agents for chemoprevention. Knowing how to best investigate the relationship between androgens and the development of prostate disease given the lack of large, randomized trials is difficult. Accumulating data challenges the assumption that alterations in serum androgens have parallel effects within the prostate hormonal environment or change androgen-regulated processes within the gland. Long-term intervention studies are needed to truly ascertain the effects of androgen manipulation on prostate tissue and disease risk. However, available data do not support the notion that restoring serum androgens to normal physiologic ranges drives prostate disease.

关键词： androgens male hypogonadism prostate testosterone

Variability of the useful life of reservoirs in tropical locations:A case study from the Burdekin Falls Dam, Australia

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International Journal of Sediment Research 2018年第2期33卷 93-106页

作者： Michelle cooper Stephen E.Lewis Thomas c.Stieglitz Scott G.Smithers college of Scilence and Engineering James Cook University centre for Tropical Water ε Aquatic Ecosystem Research TropWATER James Cook University

Large dam construction for irrigation, hydropower, water supply, and flood control in tropical to subtropical areas increased markedly after 1950. Many of the dams built during this period have filled with sediment and no longer perform to their original design specifications; in many cases, forecast dam life was greatly overestimated. This study investigates the useful life of Burdekin Falls Dam(BFD), northeastern Australia and compares the findings with other tropical reservoirs. Using two independent methods it is estimated that between 61 and 65 million m3 of sediment has been deposited in the reservoir over the 24 years of operation through 2011. This sediment volume equates to an average of0.15% of capacity lost per year since construction was completed. If current sediment loads/climate regimes persist, reservoir capacity will be reduced by 50% after 345 years. However, the useful life of the BFD reduces to just 276 years when drawdown data are considered; these data show reservoir use would be affected once 40% of storage was filled with sediment, with a 60% drawdown return period of 1 in 15 years. When compared to similar large tropical to sub-tropical reservoirs, the BFD has a slightly longer reservoir useful life than dams in India and a much longer half-life than for both similar-sized and larger dams in china, Brazil, and Iran. Properties of the BFD that promote a longer useful life include a lower trap efficiency, relatively low annual sediment load delivered to the reservoir, limited sediment deposition behind the dam wall(and uniform distribution of deposited sediment), and the export of highly turbid annual floodwaters before settling and deposition of any remaining sediment within the reservoir.

关键词： Reservoir half-life Lake Dalrymple Sediment trapping Trap efficiency Tropical reservoir Useful life