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1.
Braz. j. biol ; 68(3): 649-655, Aug. 2008. ilus, tab
Article in English | LILACS | ID: lil-493585

ABSTRACT

Bipedalism has evolved on numerous occasions in phylogenetically diverse lizard families. In this paper we describe, for the first time, bipedal locomotion on South American lizards, the sand-dweller Liolaemus lutzae and the generalist Tropidurus torquatus. The lizards were videotaped running on a racetrack and the sequences were analyzed frame by frame. The body posture, as a whole, diverged a lot during bipedal locomotion between the two species, even though there was no difference regarding their sprint performance. The locomotor behavior of L. lutzae is, in general, more similar to the one observed on other sand-dweller lizards. Certain particularities are common, such as the digitigrade posture at footfall and throughout stance, trunk angles; and tail posture. In contrast, T. torquatus exhibited high trunk angles and dragged its tail, in a posture compared to basilisks. This body posture could be related to certain characteristics and obstacles of a microhabitat such as the one around lakes and streams (basilisks) and the one with compact shrubby vegetation (T. torquatus).


O bipedalismo apareceu em inúmeras ocasiões em famílias de lagartos filogeneticamente diversas. Neste trabalho, descrevemos, pela primeira vez, locomoção bipedal em lagartos sul-americanos, o lagarto de hábito terrestre Liolaemus lutzae e o generalista Tropidurus torquatus. Os lagartos foram filmados correndo em uma pista de corrida e as seqüências foram analisadas quadro a quadro. A postura corporal, como um todo, divergiu bastante durante a locomoção bipedal das duas espécies, mesmo quando não houve diferença significativa em relação ao desempenho locomotor. O comportamento locomotor de L. lutzae é, em geral, similar ao observado em outros lagartos especialistas em solos arenosos. Certas particularidades são comuns, como a postura digitígrada no momento de apoio e durante a fase de apoio; ângulos do corpo e postura da cauda. Em contraste, T. torquatus exibiu altos ângulos corporais e arrastava sua cauda, numa postura comparada à dos lagartos basiliscos. Este tipo de postura corporal pode estar relacionado com certas características e obstáculos de um microhabitat como ao redor de rios e riachos (basiliscos) e uma vegetação de arbustos compacta (T. torquatus).


Subject(s)
Animals , Male , Lizards/physiology , Locomotion/physiology , Posture/physiology , Brazil , Lizards/classification
2.
Braz. j. med. biol. res ; 36(9): 1135-1141, Sept. 2003. ilus, tab
Article in English | LILACS | ID: lil-342863

ABSTRACT

Brazil's scientific community is under pressure. Each year there is an increase in its contribution to international science and in the number of students who are trained to do research and teach at an advanced level. Most of these activities are carried out in state and federal universities, but with government funding that has decreased by more than 70 percent since 1996. Interviews with graduate students, post-doctoral fellows and professors in one university department with a strong research tradition illustrate the level of stress engendered by the conflict between increasing competition and diminishing resources, and serve to underscore the negative effects on creativity and on the tendency to choose science as a career


Subject(s)
Humans , Burnout, Professional , Career Choice , Competitive Behavior , Research , Research Personnel , Brazil , Goals , Interview, Psychological , Public Sector , Research Personnel
3.
Arq. bras. med. vet. zootec ; 54(5): 551-554, out. 2002. ilus
Article in Portuguese | LILACS | ID: lil-328937

ABSTRACT

To evaluate the precision of the DNA tests using the non-automatized technique for individual identification and parentage tests, 105 Rottweiler dogs were studied using the primer CMR S. The sample was composed of 39 animals belonging to 11 complete families and their progenies, and 66 non related individuals until the second generation, derived from kennels located in the states of Minas Gerais and Säo Paulo. The CMR S primer was used for the Polimerase Chain Reaction (PCR). The results showed the inefficiency of the technique, even when analyzed through the automated gel analysis system. Also showed the impossibility of its commercial use due to the fact of does not permit the storage of data for subsequent use


Subject(s)
Deoxyribonucleases , Dogs
4.
Arq. bras. med. vet. zootec ; 54(3): 309-313, jun. 2002. tab
Article in Portuguese | LILACS | ID: lil-328400

ABSTRACT

Foram utilizados 46 animais da raça Gir, registrados na Associaçäo Brasileira de Criadores de Zebu, provenientes de cinco fazendas situadas no Estado de Minas Gerais, com o objetivo de avaliar a eficiência dos microssatélites BM2113, ILSTS005, ILSTS008, ETH131 e RM88 em testes de verificaçäo de parentesco. Os locos BM2113, ILSTS005, ETH131 e RM88 mostraram-se eficientes, apresentando valores de PE2 (probabilidade de exclusäo quando os dois progenitores säo genotipados) entre 0,62 e 0,69 e PIC2 (conteúdo de informaçäo polimórfica quando os dois progenitores säo genotipados) entre 0,78 e 0,83. O mesmo näo ocorreu para o loco ILSTS008, o qual apresentou baixos valores de PE2 (0,24) e PIC2 (0,41)


Subject(s)
Cattle , DNA
5.
Arq. bras. med. vet. zootec ; 51(1): 125-7, fev. 1999. tab
Article in Portuguese | LILACS | ID: lil-257154

ABSTRACT

Foram analisados testes de tipagem sangüínea de 91 animais da raça Gir, pertencentes a um rebanho altamente selecionado para produçäo leiteira. Pelo método de famílias de touros foram estudadas as progênies dos três principais touros fundadores do rebanho. Três novos fenogrupos foram identificados e suas freqüências na amostra foram: B(P)QTE'3G'P', 17,03 por cento; BGKO1TY2D'E'1, 10,98 por cento e BGKY2A'(B')D'E'3G'P'Q', 8,79 por cento


Subject(s)
Animals , Male , Cattle/blood , Blood Group Antigens
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