977 resultados para Algorítimo de Rubinstein-Thompson


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Today, the quality of a scientific article depends on the periodical in which it is published and on the number of times the article is cited in the literature. In Brazil, the criteria for the evaluation of this scientific production are improving. However, there is still some resistance, with authors arguing that Brazilian publications must be preferentially addressed to the national readers and, therefore, they should ideally be written in Portuguese. In order to determine the kind of scientific journals cited in the reference lists of articles published in medical periodicals edited in Brazil, in the present study we determine the rate of Portuguese/English citations. Three issues of 43 periodicals (19 indexed in SciELO, 10 in PubMed, 10 in LILACS, and 4 in the ISI-Thompson base) of different medical specialties were analyzed, and the number of both Portuguese and English citations in the reference list of each article was recorded. The results showed that in Brazilian-edited journals the mean number of citations/article was 20.9 ± 6.9 and the percentage of citations of international non-Brazilian periodicals was 86.0 ± 11.2%. Of the latter, 94.4 ± 7.0 are indexed by ISI-Thompson. Therefore, we conclude that Brazilian medical scientists cite the international non-Brazilian periodicals more than the national journals, and most of the cited papers are indexed by ISI-Thompson.

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An analysis of scientific bibliographic productivity using the Hirsch h-index, information from the Institute of Scientific Information database and the Curriculum Lattes (CNPq, Brazil) was performed at the Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo (FFCLRP-USP) that has four departments in natural, biological and social sciences. Bibliometric evaluations of undergraduate programs showed a better performance of the departments of Chemistry (P < 0.001) and Biology (P < 0.001) when compared to the departments of Physics and Mathematics and Psychology and Education. We also analyzed the scientific output of the six graduate programs of FFCLRP: Psychology, Psychobiology, Chemistry, Physics Applied to Medicine and Biology, Comparative Biology, and Entomology. The graduate program in Psychology presented a lower h-index (P < 0.001) and had fewer papers indexed by the ISI web of science (P < 0.001) when compared to the other graduate programs. The poorer performance of the Psychology program may be associated with the limited coverage by the Thompson Institute of Scientific Information database.

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A series of studies have shown that the heavy burdens of diarrheal diseases in the first 2 formative years of life in children living in urban shanty towns have negative effects on physical and cognitive development lasting into later childhood. We have shown that APOE4 is relatively common in shanty town children living in Brazil (13.4%) and suggest that APOE4 has a protective role in cognitive development as well as weight-for-height in children with heavy burdens of diarrhea in early childhood (64/123; 52%), despite being a marker for cognitive decline with Alzheimer’s and cardiovascular diseases later in life. APOE2 frequency was higher among children with heaviest diarrhea burdens during the first 2 years of life, as detected by PCR using the restriction fragment length polymorphism method, raising the possibility that ApoE-cholesterol balance might be critical for growth and cognitive development under the stress of heavy diarrhea burdens and when an enriched fat diet is insufficient. These findings provide a potential explanation for the survival advantage in evolution of genes, which might raise cholesterol levels during heavy stress of diarrhea burdens and malnutrition early in life.

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Toisen maailmansodan jälkeisenä ajanjaksona Iso-Britannia ja Ranska päätyivät useissa siirtomaissaan vastakumouksellisiin sodankäynnin konflikteihin. Nämä konfliktit kytkeytyivät siirtomaiden itsenäistymispyrkimyksiin ja kylmän sodan maailmanpoliittiseen tilanteeseen. Konflikteissa Ison-Britannian ja Ranskan siviili- ja sotilasviranomaiset kehittivät innovatiivisesti vastakumouksellisen sodankäynnin menetelmiään. Läntisissä valtioissa tehtiin 1960-luvulla myös merkittävä määrä vastakumouksellisen sodankäynnin tutkimusta. Tämän tutkimusjakson keskeisimpiä teoreetikkoja olivat ranskalainen David Galula (1919 - 1967) ja britit Robert Thompson (1916 - 1992) ja Frank Kitson (1926 -). Tämän tutkimuksen tavoitteena on selvittää, mitkä tekijät yhdistivät David Galulan, Robert Thompsonin ja Frank Kitsonin kumouksellisen ja vastakumouksellisen sodankäynnin teorioita. Tutkimuksessa on käytetty metodina tulkitsevaa diskurssianalyysiä teoreetikkojen kumouksellisen ja vastakumouksellisen sodankäynnin näkemysten tulkitsemiseksi. Tulkinta on suoritettu sitomalla teoriat historialliseen ja henkilöiden taustat käsittävään kontekstiin. Laadullisella sisällönanalyysillä on tunnistettu teoreetikkojen taustoista niitä tekijöitä, joilla voidaan katsoa olleen merkitystä teorioiden muodostumiselle. Diskurssianalyysin rinnalla on käytetty tapaustutkimusta Galulan, Thompsonin ja Kitsonin teorioiden ja heidän taustatekijöidensä vertaamiseksi. Keskeisen tutkimusaineiston muodostivat Galulan, Thompsonin ja Kitsonin vastakumouk-sellista sodankäyntiä käsittelevät kirjat sekä heidän kirjoittamansa muistelmat. Tätä tutkimusaineistoa täydennettiin teoreetikkoja ja vastakumouksellista sodankäyntiä käsittelevällä tutkimuskirjallisuudella. Tutkimuksen tärkeimpänä havaintona voidaan pitää sitä, että teoreetikkojen näkemykset kumouksellisesta ja vastakumouksellisesta sodankäynnistä ovat pitkälti yhteneväisiä. Tämän johtui siitä, että kumouksellinen sodankäynti havainnollistettiin pitkälti Mao Zedongin vallankumouksellisen sodankäynnin mallin kautta. Kumouksellisen sodankäynnin ytimeksi nähtiin syy tai aate, jota käytettiin kansan tuen voittamiseksi. Kaikki teoreetikot korostivat kumouksellisen sodankäynnin poliittista ulottuvuutta. Tämän takia vastakumouksellisen sodankäynnin tuli olla ensisijaisesti poliittisesti johdettua toimintaa, jota turvallisuusjoukot tukevat. Teoreetikot näkivät asevoimien roolin ja toimintaperiaatteet vastakumouksellisessa sodankäynnissä pitkälti yhteneväisesti. Teoreetikkojen taustoissa havaittiin useita näkemysten yhtenäisyyttä selittäviä tekijöitä.

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Pictured here from left to right are: R. Nairn, W. Jolly, M. Miller, C. Shaver, C. Slemon, O. Loberg, W. Thompson.

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Pictured here from left to right are: W. Thompson, M. Williams, M. Stevens, C. McMillan.

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At the time the language lab at the Glenridge Campus was state of the art. It was equiped with 18 individual student cubicles and a main console. In this photograph Mr. Guy Gauthier, Instructor in French, demonstrates the equipment manufactured by Thompson-Ramo-Wooldridge Corp. to one of his French classes. Mr. Gauthier was one of the original Brock faculty members.

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From left to right. Top: Sean Dowd, Dave Muirhead, Mike Thompson, Rick Cicchine, Mark Thomas, John Ahlstedt, Mark Reynolds, Tom Kent, and Tony Biernacki (Coach). Bottom: Bob Nguyen (Coxie).

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Back Row: J.B. Owens, Ross Smith (Head Coach), Adam Frost, Derrick Harwood, Dave DeRose, Bill Arniel, Danny Mazor, Alan Ross, Randy McKeller, Pete McDougall, Ray D'Archi, Kelvin Oda, Mark Pelletier, Eric Thompson, Marty Houston, Ken White (Asst. Coach) Front Row: Peter Love, Chris Peskett, Duff Porteous, Bart Ward, Dave Sohmer, Gary Gautier, Ken Murray, Dave Tamowski, Steve Shaughnessy, Jeff Wood Absent: Alfred Esmaily, Luc Gignac, Fred Kovacs, Andrew Norman

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Fifty kHz rat vocalizations are theorized to reflect a positive affective state, and index the reward value of stimuli (Knutson, Burgdorf & Panksepp, 2002; Panksepp & Burgdorf, 2003; Brudzynski,2005). Previous studies have identified the neurochemical substrate of this behaviour to be dependent on dopaminergic activity at the nucleus accumbens shell (Burgdorf, Knutson, Panksepp & Ikemoto, 2001; Thompson, Leonard & Brudzynski, 2006). The utilization of d-amphetamine (a non-selective dopamine agonist) in these studies does not address the specific dopamine receptor types involved. The present study aims to identify the role of the D2- like family of receptors in the nucleus accumbens shell in the production of 50 kHz vocalizations in adult rats. Single injections of quinpirole in a saline vehicle were administered to the nucleus accumbens shell of 57 rats, and the number of 50 kHz vocalizations were recorded. An inverted V-shaped relationship was found between quinpirole dose (0.5 ~g, 3 ~g, 6 ~g, 1 0 ~g and 20 ~g, all in 0.2~1 saline) and the mean number of 50 kHz calls produced. Quinpirole successfully elicited significantly more 50 kHz calls than did a saline control at the 6 ~g dose, as did 7 ~g/0.2 ~l of d-amphetamine injections into the same brain site. To test whether a selective D2 antagonist could reverse elicited 50 kHz calling, double injections were given that used either saline or raclopride as a pretreatment before quinpirole injections. Saline followed by 6 ~g/0.2 ~l of quinpirole elicited significantly more 50 kHz vocalizations than did a double injection of saline, while pretreatment with an equimolar dose of raclopride reduced elicited calls to control levels. Raclopride was also used as a pretreatment of 7 ~g/0.2 ~l d-amphetamine, which elicited significantly fewer 50 kHz vocalizations than saline followed by amphetamine, replicating the finding of Thompson, Leonard & Brudzynski (2006).Subcutaneous injections of 0.5 mg/kg and 1.5 mg/kg of quinpirole produced a similar number of 50 kHz vocalizations as subcutaneous injection of saline. Wider dose ranges may be explored in fiiture research. Thus, direct activation of the Da-like receptors in the nucleus accumbens shell was sufficient to elicit 50 kHz vocalizations in adult rats, an effect which was reversed with selective local antagonism of Da-like receptors. The Da-like receptor family also appears necessary for pharmacological activation of 50 kHz calling, as d-amphetamine was no longer able to effectively elicit these vocalizations from the nucleus accumbens shell when the Da-receptor family was antagonized with raclopride. The acoustic parameters of elicited vocalizations remained typical of rat 50 kHz calls. Detailed analyses of the acoustic characteristics of elicited calls indicated significant increases in call duration and peak frequency across drug injection groups, particularly among quinpirole dose groups. The implications of these findings are not yet clear, but may represent an important direction for future research into the coding of semiotic content into affective signals in rats.

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Higher plants have evolved a well-conserved set of photoprotective mechanisms, collectively designated Non-Photochemical Quenching of chlorophyll fluorescence (qN), to deal with the inhibitory absorption of excess light energy by the photosystems. Their main contribution originates from safe thermal deactivation of excited states promoted by a highly-energized thylakoid membrane, detected via lumen acidification. The precise origins of this energy- or LlpH-dependent quenching (qE), arising from either decreased energy transfer efficiency in PSII antennae (~ Young & Frank, 1996; Gilmore & Yamamoto, 1992; Ruban et aI., 1992), from alternative electron transfer pathways in PSII reaction centres (~ Schreiber & Neubauer, 1990; Thompson &Brudvig, 1988; Klimov et aI., 1977), or from both (Wagner et aI., 1996; Walters & Horton, 1993), are a source of considerable controversy. In this study, the origins of qE were investigated in spinach thylakoids using a combination of fluorescence spectroscopic techniques: Pulse Amplitude Modulated (PAM) fluorimetry, pump-probe fluorimetry for the measurement of PSII absorption crosssections, and picosecond fluorescence decay curves fit to a kinetic model for PSII. Quenching by qE (,..,600/0 of maximal fluorescence, Fm) was light-induced in circulating samples and the resulting pH gradient maintained during a dark delay by the lumenacidifying capabilities of thylakoid membrane H+ ATPases. Results for qE were compared to those for the addition of a known antenna quencher, 5-hydroxy-1,4naphthoquinone (5-0H-NQ), titrated to achieve the same degree of Fm quenching as for qE. Quenching of the minimal fluorescence yield, F0' was clear (8 to 130/0) during formation of qE, indicative of classical antenna quenching (Butler, 1984), although the degree was significantly less than that achieved by addition of 5-0H-NQ. Although qE induction resulted in an overall increase in absorption cross-section, unlike the decrease expected for antenna quenchers like the quinone, a larger increase in crosssection was observed when qE induction was attempted in thylakoids with collapsed pH gradients (uncoupled by nigericin), in the absence of xanthophyll cycle operation (inhibited by DTT), or in the absence of quenching (LlpH not maintained in the dark due to omission of ATP). Fluorescence decay curves exhibited a similar disparity between qE-quenched and 5-0H-NQ-quenched thylakoids, although both sets showed accelerated kinetics in the fastest decay components at both F0 and Fm. In addition, the kinetics of dark-adapted thylakoids were nearly identical to those in qEquenched samples at F0' both accelerated in comparison with thylakoids in which the redox poise of the Oxygen-Evolving Complex was randomized by exposure to low levels of background light (which allowed appropriate comparison with F0 yields from quenched samples). When modelled with the Reversible Radical Pair model for PSII (Schatz et aI., 1988), quinone quenching could be sufficiently described by increasing only the rate constant for decay in the antenna (as in Vasil'ev et aI., 1998), whereas modelling of data from qE-quenched thylakoids required changes in both the antenna rate constant and in rate constants for the reaction centre. The clear differences between qE and 5-0H-NQ quenching demonstrated that qE could not have its origins in the antenna alone, but is rather accompanied by reaction centre quenching. Defined mechanisms of reaction centre quenching are discussed, also in relation to the observed post-quenching depression in Fm associated with photoinhibition.

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This study investigated the effectiveness of a computer program, PERSONAL CAREER DIRECTIONS (PC DIRECTIONS) (Anderson, Welborn, & Wright, 1983) on career planning and exploration for twenty-four Brock University students (18 women and 6 men) who requested career planning assistance at the Career/Placement Services of the Counselling Centre. A one-group pretest/posttest design was used in the study_ Progress in career planning and exploration was measured by Career Planning (CP) and Career Exploration (CE) scales of the Career Development Inventory (College and University Form) (Super, Thompson, Lindeman, Jordaan, & Myers, 1981). A paired samples 2-tailed t test for Career Development Attitudes (CDA) , the combined CP and CE scales, revealed the posttest scores were significantly higher than the pretest scores, t(23) = 3.74, 2 < .001. Student progress was also assessed by self-report lists of job titles which reflected positive changes after students used PC DIRECTIONS. In response to several questions, students' attitudes were more positive than negative toward the program. Implications are that PC DIRECTIONS is an effective component in promoting career planning for university students. Further studies may reveal that different types of students may benefit from different interventions in the career planning process.

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The purpose of this study was to investigate the relationship between learning styles and academic achievement in postsecondary education. It was the intent of the study to establish if there was a relationship between student learning style, teacher style, learner/teacher matching and/or mismatching, student gender and age, to the academic grades of students. This study was basically a replication of a study completed by Mary J. Thompson and Terrance P. O'Brien in 1991 on two campuses of a southeast community college in the United States. In the present study, 243 students and 18 teachers from two different campuses of a community college in the Province of Ontario participated in the research. All participants were administered the Gregorc Style Delineator and students identified by program, age and gender. Data were tested by two analysis of variance (ANOVA) models. In the first ANOVA model considered in this study, significant main effects were manifested in regard to the teaching style, age group and gender. With the exception of gender, these findings were very similiar to those of the original study. Duncan's multiple range test revealed that Concrete Sequential (CS) teachers assigned significantly lower grades than did teachers dominant in any of the other three learning styles. Post hoc testing revealed that students 25 years of age and older received significantly higher grades than did younger students. Female students also received significantly higher grades than did male students. In the second ANOVA model student/teacher learning style match/mismatch did emerge as a significant main effect. However, Duncan's multiple range test and Chi square analysis did not substantiate the relationship. Forty-eight references are cited.

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An interdisciplinary approach is used to identify a new graphic novel genre, 'comics camet', and its key features. The study situates comics camet in a historical context and shows it to be the result of a cross-pollination between the American and French comics traditions. Comics camet incorporates features from other literary genres: journalism, autobiography, ethnography and travel writing. Its creators, primarily European rriales, document their experiences visiting countries that Europe has traditionally defined as belonging to the 'East'. A visual and narrative analysis, using theoretical perspectives derived from cultural and postcolonial studies, examines how comics camet represents the non-European other and identifies the genre's ideological assumptions. Four representative texts are examined: Joe Sacco's Palestine (2001), Craig Thompson's, Camet de Voyage (2004), Guy Delisle's Pyongyang (2005) and Mrujane Satrpi's Persespolis 2 (2004). The study concludes that the comics camet genre simultaneously reinforces and challenges stereotypical assumptions about non-European people and places.