201 resultados para Vigour


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Studies on the pollination biology of Eriocaulaceae are scarce although particularly interesting because of its inclusion in the Poales, a predominantly wind-pollinated order. The pollination biology of Syngonanthus elegans (Bong.) Ruhland was studied during two annual flowering periods to test the hypothesis that insect pollination was its primary pollination system. A field study was carried out, including observations of the morphology and biology of the flowers, insect visits and pollinator behaviour. We also evaluated seed set, seed germination and seedling development for different pollination modes. Although seeds were produced by self-pollination, pollination by small insects contributed most effectively to the reproductive success of S. elegans, resulting in the greatest seed set, with the highest germination percentage and optimum seedling vigour. The. oral resources used by flower visitors were pollen and nectar that was produced by staminate and pistillate flowers. Self-pollination played a minor role and its consequence was inbreeding depression.

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A common perspective today is that sportspeople must train and compete to a level of exertion beyond the ‘pain threshold’ if they are to succeed; a view that has given rise to the popular expression ‘No Pain, No Gain’. Indeed, a common aphorism is that the health and quality of life of individuals and of the wider population is positively correlated with the frequency and vigour of physical exercise. In the period when modern sports were taking on their present characteristics (approximately 1850-1920), the prevailing opinions about the health and well-being effects of exercise were far more cautious, however. While the benefits of moderate exercise for physical and mental well-being went without question, too great an exertion was considered to be as risky as too little, causing ‘strain’ with the potential to inflict lasting and potentially fatal damage, including mental and physical complaints as diverse as neuralgia and ‘athletes’ heart’. The supposedly more strenuous sports, such as football, athletics and rowing, and the training required for them came under particular scrutiny in medical and popular discourses. This paper, an exercise in historical sociology, examines these discourses to demonstrate how advice about the risks on health of participating in sports and of too little or too much exercise more generally, was informed by prevailing physiological models and the interpretation of these within the medical profession and the wider population. The data sources include medical journals and texts, and sports training manuals from the period under investigation.

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Dietary therapies are routinely recommended to reduce disease risk; however, there is concern they may adversely affect mood. We compared the effect on mood of a low-sodium, high-potassium diet (LNAHK) and a high-calcium diet (HC) with a moderate-sodium, high-potassium, high-calcium Dietary Approaches to Stop Hypertension (DASH)-type diet (OD). We also assessed the relationship between dietary electrolytes and cortisol, a stress hormone and marker of hypothalamic–pituitary–adrenal (HPA) axis activity. In a crossover design, subjects were randomized to two diets for 4 weeks, the OD and either LNAHK or HC, each preceded by a 2-week control diet (CD). Dietary compliance was assessed by 24 h urine collections. Mood was measured weekly by the Profile of Mood States (POMS). Saliva samples were collected to measure cortisol. The change in mood between the preceding CD and the test diet (LNAHK or HC) was compared with the change between the CD and OD. Of the thirty-eight women and fifty-six men (mean age 56·3 (sem 9·8) years) that completed the OD, forty-three completed the LNAHK and forty-eight the HC. There was a greater improvement in depression, tension, vigour and the POMS global score for the LNAHK diet compared to OD (P < 0·05). Higher cortisol levels were weakly associated with greater vigour, lower fatigue, and higher levels of urinary potassium and magnesium (r 0·1–0·2, P < 0·05 for all). In conclusion, a LNAHK diet appeared to have a positive effect on overall mood.

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We report the initial validation of a multi-component assessment model for monitoring training distress among athletes. The model combines measures of mood disturbance with measures of perceived stress and symptom intensity. Altogether, 492 athletes completed the 10-item Perceived Stress Scale (PSS-10; Cohen et al., 1983), the 24-item Brunel Mood Scale (BRUMS; Terry et al., 2003), and a checklist of 19 symptoms associated with acute overtraining (Fry et al., 1994). Six training distress factors were identified by an exploratory factor analysis: ‘‘depressed mood’’, ‘‘perceived vigour’’, ‘‘physical symptoms’’, ‘‘sleep disturbance’’, ‘‘perceived stress’’, and ‘‘general fatigue’’. Comparisons of group means of these factors with a previously validated inventory were consistent with theoretical predictions and provided evidence of construct validity. Internal consistency of the subscales was also confirmed, with Cronbach alphas ranging from 0.72 to 0.86. Together, these findings suggest that this multi-component model provides a sound conceptual basis for the assessment of training distress among athletes.

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We are currently witnessing a renewed vigour to ongoing concerns about the sexualisation of young women and girls in western popular culture. This paper takes up Angela McRobbie’s concerns that the commercial sphere has become a primary site for talking about, and educating, girls and young women (McRobbie, 2008). I first explore the growth in ‘expert’ commentary, on girls and sexualisation, drawing on the work of a number of commentators and authors from the USA, the UK and Australia, who have become ubiquitous media commentators on issues facing girls, including sexualisation. I then draw on feminist and education theory to explore the possible limitations of how education is conceived within this cultural site, particularly with respect to constructions of girls’ resistance. In the final part of the paper I show how girls’ resistance is complicated in postfeminist, neoliberal societies and I propose that education scholarship and practice must confront the ways in which girls’ resistance is bound up in their developing classed and raced identities.

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As to the former, a glance at the contents list of this volume will demonstrate both the maturity and the vigour of theoretical debate within psychology. There is a level of sophistication here that should be the cause of quiet celebration.

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Foram verificados os efeitos de diferentes períodos de controle e convivência de plantas daninhas (0; 14; 28; 42; 56; 70; 84 e 98 dias) na cultura do amendoinzeiro (Arachis hypogaea L.) em Moji-Guaçu (SP). As principais espécies invasoras da área experimental foram: Acanthospermum australe (Loef.) O. Kuntz, Waltheria indica L., Borreria alata DC., Richardia scabra L., Rhynchelytrum repens (Nees) Stapf. et Hubb. e Diodia teres Walt. de maneira geral, durante quase todo o ciclo, a espécie de maior importância relativa foi A. australe, sendo suplantada por outras espécies apenas na colheita, quando já estava encerrando seu ciclo de desenvolvimento. O período inicial de controle das plantas daninhas, além de reduzir a densidade da comunidade infestante, diminuiu sua riqueza em espécies e alterou a importância relativa das populações. A matocompetição resultou na redução do crescimento do amendoinzeiro, principalmente a partir de 42 dias de convivência, afetando a altura das plantas, a área foliar, o índice de área foliar e o acúmulo epígeo de matéria seca. Não foram afetados os números de ramos e de folíolos por planta, nem a qualidade dos grãos e o vigor das sementes do amendoim. A produção de frutos foi reduzida ao redor de 31,5% em decorrência da interferência das plantas daninhas. O período total de prevenção da interferência na produção foi de 14 dias e o período anterior à interferência foi de 70 dias.

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É de interesse prático, quando se dispõe de diferentes lotes de sementes, conhecer a qualidade fisiológica intrínseca a cada um. Objetivou-se determinar a qualidade fisiológica de lotes de sementes da leguminosa forrageira tropical, Macrotyloma axillare cv. Java, com utilização de diferentes metodologias para realização dos testes germinação e vigor. Determinou-se a pureza física dos lotes, o peso de mil sementes, a germinação com e sem escarificação (TG) e o vigor (índice de velocidade de germinação (IVG), primeira contagem, envelhecimento acelerado e condutividade elétrica) de três lotes de sementes. Diferenças na qualidade fisiológica inicial de sementes escarificadas foram observadas pelo teste de germinação. Pelos resultados dos testes de primeira contagem e IVG não foi possível detectar diferenças na qualidade fisiológica das sementes; o envelhecimento acelerado das sementes escarificadas pode ser realizado a 41º C por 72 horas ou a 45º C por 48 horas; o teste de condutividade elétrica mostrou-se adequado para diferenciar os lotes, a partir de 48 horas de embebição.

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Considerada importante praga do algodoeiro, a mosca-branca Bemisia tabaci biótipo B pode através de sua alimentação, diminuir o vigor das plantas, trasmitir vírus e prejudicar a qualidade da fibra. Visando avaliar a resistência de genótipos de algodoeiro, Gossypium hirsutum (L.), à mosca-branca Bemisia tabaci biótipo B, realizaram-se testes de atratividade e não-preferência para oviposição, com e sem chance de escolha, em telado, a temperatura ambiente. Verificou-se baixa atratividade das plantas dos genótipos Fabrika, CNPA Ita 90, Makina, Coodetec 407 e IAC 01-639 CPA 02-24 a adultos dessa mosca-branca, o que pode representar um componente de resistência destes materiais genéticos ao inseto. Os genótipos BRS Aroeira, Coodetec 406, Fabrika e Coodetec 401 apresentaram resistência do tipo não-preferência para oviposição, nos testes com e sem chance de escolha. Os números de tricomas e de glândulas de gossipol por cm² não foram adequados para se avaliar a não-preferência para oviposição de adultos da mosca-branca em genótipos de algodoeiro.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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The objective of this study was to evaluate the reproductive performance of Santa Ines rams subjected to successive semen collections in an Amazonian climate. Four rams were subjected to successive ejaculations during a maximum period of three hours. This procedure was repeated three times at 15-day intervals. Sexual and behavioural (libido) and andrological (testicular and seminal) assessments were performed. A total of 81 ejaculates were collected. Libido and semen vigour, volume, appearance and concentration decreased as the ejaculation frequency increased (P<0.05) and sperm motility showed a decreasing trend (P=0.06). The seminal pH increased over the sequence of collections (P<0.05). The only significant differences observed between individual rams were the variable scrotal circumference and the percentages of live sperm and sperm abnormalities (P<0.05). All the parameters of the first ejaculation were within the normal range for this species, which suggests that the local climatic conditions (high temperature and humidity) did not affect the behavioural, testicular or seminal parameters of experimental rams. Our findings indicate that the reproductive performance of Santa Ines rams could be affected by the intensification of ejaculation frequency; however, individual male variation needs to be taken into consideration.

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The Japanese apricot (Prunus mume Sieb. et Zucc.) is a fruit tree of the Rosaceae family which produces very acid and bitter fruits, highly appreciated by Orientals. In Brazil, this species has been studied as a rootstock for peach and nectarine trees, its main advantage being the reduction in plant vigour, which can favour the production of compact trees and orchard cultural treatments. This study was conducted in the Vegetable Production Department of FCAV/UNESP, Jaboticabal Campus, São Paulo State, Brazil, and the objective was to examine the effect of wounding the herbaceous cutting bases on the rooting of four Japanese apricot clones. The clones were obtained from plants under cultivation in the Instituto Agronomico de Campinas, Brazil, and were identified as Clones 02, 05, 10 and 15. The stock plants, obtained through herbaceous cuttings, were maintained under lath house conditions (50% of natural light). Cuttings 12 cm long with 3 to 5 leaves were collected from these clones and prepared. The experiment was carried out in a completely randomised design with 4 repetitions of 20 cuttings per replication, in a factorial 4 x 2 design, the clone factor having 4 levels (Clones 02, 05, 10 and 15) and the wounding factor at 2 levels of incisions into the cutting base (with and without). All the cuttings were treated with 2000 mg.L-1 of IBA for five seconds. Differences between the clones were observed concerning the rooting percentage, dead cuttings, number and length of roots. The incision (wound) at the base of the herbaceous cuttings of the Japanese apricot increased the number of roots and improved the distribution of these in the damaged tissue but the results were not considered sufficiently beneficial to make the treatment worthwhile.

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It is fundamentally important that adequate tests are used to evaluate the physiological quality of produced and commercialized seeds. The objective of this work was to study accelerated ageing and controlled deterioration to evaluate seed vigour in beetroot, seeking to associate these results with seedling emergence in the field. Consequently, five seed lots of Top Tall Early Wonder cultivar were submitted to the tests of germination, seedling emergence in the field, accelerated ageing (using periods of 24, 48 and 72 hours at 42 degrees C) and controlled deterioration (seeds with moisture contents of 22, 24 and 26% at 41 degrees C and 45 degrees C for 12, 24 and 36 hours). Combinations of 72h at 42 degrees C for the accelerated ageing test and 45 degrees C with 24% moisture content for 24h for the controlled deterioration test were sensitive enough to evaluate the physiological potential of beetroot seeds, providing information that was compatible with results of the seedling emergence in the field.

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Com o objetivo de avaliar o efeito de diferentes doses de cloreto de mepiquat (0, 50, 75, 100 e 125 g/ha) e de thidiazuron (0, 45, 60 e 75 g/ha) sobre as características fisiológicas de sementes de algodoeiro, foi conduzido, na UNESP, Jaboticabal, SP, um experimento inteiramente casualizado, num arranjo fatorial (5x4), com quatro repetições. Com o aumento da dose de cloreto de mepiquat, verificou-se aumento do peso de 100 sementes e do índice de velocidade de emergência de plântulas. O efeito do cloreto de mepiquat e do thidiazuron sobre a matéria seca das plântulas foi antagônico. A porcentagem de germinação e o comprimento do hipocótilo não foram significativamente afetados pelo cloreto de mepiquat, pelo thidiazuron e pela interação entre eles.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)