Interanimal "memory" transfer: results from brain and liver homogenates     

B Frank  D G Stein  J Rosen 《Science (New York, N.Y.)》1970,169(943):399-402

Sixty mice received either shock or no shock in a shuttle box, or nonspecific stress in another apparatus. Brain and liver homogenates from these animals were then injected into 120 naive recipients, who were all tested in the shuttle box. Subjects receiving brain or liver from shocked or stressed donors had significantly higher latencies than control counterparts. These results are interpreted in terms of stress, rather than a memory transfer hypothesis.  相似文献   

Atmospheric trends in methylchloroform and the global average for the hydroxyl radical     

Prinn R  Cunnold D  Rasmussen R  Simmonds P  Alyea F  Crawford A  Fraser P  Rosen R 《Science (New York, N.Y.)》1987,238(4829):945-950

Frequent atmospheric measurements of the anthropogenic compound methylchloroform that were made between 1978 and 1985 indicate that this species is continuing to increase significantly around the world. Reaction with the major atmospheric oxidant, the hydroxyl radical (OH), is the principal sink for this species. The observed mean trends for methylchloroform are 4.8, 5.4, 6.4, and 6.9 percent per year at Aldrigole (Ireland) and Cape Meares (Oregon), Ragged Point (Barbados), Point Matatula (American Samoa), and Cape Grim (Tasmania), respectively, from July 1978 to June 1985. These measured trends, combined with knowledge of industrial emissions, were used in an optimal estimation inversion scheme to deduce a globally averaged methylchloroform atmospheric lifetime of 6.3 (+ 1.2, -0.9) years (1sigma uncertainty) and a globally averaged tropospheric hydroxyl radical concentration of (7.7 +/- 1.4) x 10(5) radicals per cubic centimeter (1sigma uncertainty). These 7 years of gas chromatographic measurements, which comprise about 60,000 individual calibrated real-time air analyses, provide the most accurate estimates yet of the trends and lifetime of methylchloroform and of the global average for tropospheric hydroxyl radical levels. Accurate determination of hydroxyl radical levels is crucial to understanding global atmospheric chemical cycles and trends in the levels of trace gases such as methane.  相似文献   

Pattern classification by adaptive machines     

C A Rosen 《Science (New York, N.Y.)》1967,156(771):38-44

Man's intelligent behavior is due in part to his ability to select, classify, and abstract significant information reaching him from his environment by way of his senses. This function, pattern recognition, has become a major focus of research by scientists working in the field of artificial intelligence. At the lowest level, pattern recognition reduces to pattern classification, which consists of the separation, into desired classes, of groups of objects, sounds, odors, events, properties, and the like; the separations are based on sets of measurements made on the entities being classified. The pattern classifier is composed of a data filter and a categorizer. The data filter selects the distinguishing features and represents them as sets of real numbers; each set is termed a pattern. The categorizer assigns each pattern to one of several desired classes. Patterns can be represented geometrically as points in an n-dimensional space; the n coordinates of each point are the numerical values of the features selected to represent the pattern. A pattern classification system separates an n-dimensional space into regions, each of which ideally contains points of only one class. One method to effect this separation is by means of ldquo;trainablerdquo; categorizers-major components of adaptive machines. They consist of networks whose internal parameters are varied according to a set of fixed rules during a training cycle. A statistically large sample of known patterns are presented, one at a time, to the networks; internal corrections are made each time a pattern is erroneously classified. Classifica-tion performance tends to improve as the set of known patterns is cycled repetitively through the machine. Finally, the adequacy of adaptation is tested by a separate set of similar patterns which have not been used in the training process. A number of different machine organizations and training rules have been developed and are being applied successfully to numerous classification problems. More difficult recognition problems requiring the aid of logioal tests and analysis, search and association, use the digital computer programmed to supplement the functions of the adaptive classifier.  相似文献   

Nuclear magnetic resonance imaging of the vitreous body   总被引：2，自引：0，他引：2  

R G González  H M Cheng  P Barnett  J Aguayo  B Glaser  B Rosen  C T Burt  T Brady 《Science (New York, N.Y.)》1984,223(4634):399-400

Imaging with proton nuclear magnetic resonance is a valuable new tool for studying the vitreous body of the eye. It is particularly suited for the detection of vitreal liquefaction and intraocular hemorrhage because of the dependence of the signal on the physical environment of water. Conversely, the vitreous body provides a new model for studying changes in proton relaxation times of protein solutions in biological systems.  相似文献   

CONTROL OF THE BLOSSOM BLIGHT STAGE OF FIRE BLIGHT     

Rosen HR 《Science (New York, N.Y.)》1932,76(1976):447-448

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基于SSR和SRAP标记的苹果品种亲缘关系分析   总被引：1，自引：0，他引：1       下载免费PDF全文

巴巧瑞  赵政阳  高华 《西北农林科技大学学报(自然科学版)》2011,39(9):123-128

【目的】用SSR和SRAP分子标记技术,分析苹果(Malus domestica Borkh.)重要栽培品种的亲缘关系,为苹果杂交育种亲本及组合的选配提供参考。【方法】用亲缘关系较近的金冠和秦冠筛选SSR和SRAP多态性引物,利用SSR和SRAP分子标记技术对37个苹果栽培品种进行遗传多样性和亲缘关系分析。【结果】筛选出了用于37个苹果主栽品种亲缘关系分析的10对SSR和10对SRAP引物,其分别产生56和64条扩增带,平均多态性比率分别为61.09%和70.8%。根据SSR+SRAP分析结果,37个苹果品种被聚为6大类。【结论】所选取的引物能够有效地揭示供试苹果品种的遗传多样性,并且苹果品种分类与传统系谱基本一致。  相似文献   

Isolation of a rel-related human cDNA that potentially encodes the 65-kD subunit of NF-kappa B   总被引：117，自引：0，他引：117  

S M Ruben  P J Dillon  R Schreck  T Henkel  C H Chen  M Maher  P A Baeuerle  C A Rosen 《Science (New York, N.Y.)》1991,251(5000):1490-1493

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Soot in urban atmospheres: determination by an optical absorption technique     

Rosen H  Hansen AD  Dod RL  Novakov T 《Science (New York, N.Y.)》1980,208(4445):741-744

We have used the high optical absorptivity of urban and source particulates to trace their "graphitic" component. The optical absorptivity and the particulate carbon loading show a strong correlation. Analyses of the data indicate that primary soot emissions compose a major fraction of the carbonaceous aerosol and put a low limit on secondary organic material produced in correlation with the ozone concentration.  相似文献   

Flavonol glycosides and novel iridoid glycoside from the leaves of Morinda citrifolia   总被引：5，自引：0，他引：5  

Sang S  Cheng X  Zhu N  Stark RE  Badmaev V  Ghai G  Rosen RT  Ho CT 《Journal of agricultural and food chemistry》2001,49(9):4478-4481

One new iridoid glycoside and five known flavonol glycosides have been isolated from the leaves of Morinda citrifolia. The new iridoid exists as an epimeric mixture in solution. Complete assignments of the proton and carbon chemical shifts for the individual epimers were accomplished on the basis of high-resolution 1D and 2D NMR data. Their antioxidative activities were measured. All of these compounds showed DPPH free radical scavenging activity at the concentration of 30 microM.  相似文献   

New prenylated benzoic acid and other constituents from almond hulls (Prunus amygdalus Batsch).   总被引：2，自引：0，他引：2  

Shengmin Sang  Karen Lapsley  Robert T Rosen  Chi-Tang Ho 《Journal of agricultural and food chemistry》2002,50(3):607-609

One new prenylated benzoic acid derivative, 3-prenyl-4-O-beta-D-glucopyranosyloxy-4-hydroxylbenzoic acid, and three known constituents, catechin, protocatechuic acid, and ursolic acid, have been isolated from the hulls of almond (Prunus amygdalus). Complete assignments of the proton and carbon chemical shifts for the new prenylated benzoic acid derivative were accomplished on the basis of high-resolution 1D and 2D nuclear magnetic resonance data. All of these compounds except ursolic acid are being reported from almond hulls (P. amygdalus) for the first time.  相似文献