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81.
Provencher V Bégin C Tremblay A Mongeau L Boivin S Lemieux S 《Obesity (Silver Spring, Md.)》2007,15(4):957-966
Objective: To assess the effects of a “Health‐At‐Every‐Size” (HAES) intervention on eating behaviors and appetite ratings in 144 premenopausal overweight women. Research Methods and Procedures: Women were randomly assigned to one of the 3 groups: HAES group, social support (SS) group, and control group (N = 48 in each group). Interventions were conducted over a 4‐month period, and measurements were taken before and after this period. Eating behaviors (cognitive dietary restraint, disinhibition, and susceptibility to hunger) were evaluated by the Three‐Factor Eating Questionnaire. Appetite ratings (desire to eat, hunger, fullness, and prospective food consumption) were assessed by visual analogue scales before and after a standardized breakfast. Results: More important decreases in susceptibility to hunger and external hunger were observed in the HAES group when compared with the SS group (p = 0.05, for susceptibility to hunger) and the control group (p = 0.02 and p = 0.005, for susceptibility to hunger and external hunger, respectively). In addition, women from the HAES group had more important decreases in postprandial area under the curve for desire to eat (p = 0.02) and hunger (p = 0.04) when compared with the control group. The change in the desire to eat noted in the HAES group was also different from the one observed in SS group (p = 0.02). Women from the HAES group experienced significant weight loss at 4 months (?1.6 ± 2.5 kg, p < 0.0001), which did not differ significantly from the SS and control groups (p = 0.09). An increase in flexible restraint was significantly related to a greater weight loss in both HAES and SS groups (r = ?0.39, p < 0.01; and r = ?0.37, p < 0.05, respectively). A decrease in habitual susceptibility to disinhibition was also associated with a greater weight loss in HAES and control groups (r = 0.31, p < 0.05; and r = 0.44, p < 0.05, respectively). Discussion: These results suggest that a HAES intervention could have significant effects on eating behaviors and appetite ratings in premenopausal overweight women, when compared with an SS intervention or a control group. 相似文献
82.
本研究在甘肃兴隆山国家级自然保护区马麝繁育场展开,分别于2012年7月和2013年8月,针对374只圈养马麝,采用基于量表的个性评价法进行评价调查。结果表明:可建立包含17个个性项目的圈养马麝个性量表,因子分析显示每个项目公因子方差和载荷均大于0. 4,各因子累计贡献率为60. 33%,表明此量表具有较好的结构效度。此外Cronbach’sα系数为0. 787,表明量表具有较高的内部一致性信度,量表设计合理;因子分析和聚类分析结果显示,可将圈养马麝划分为五大个性维度:侵略性、社会性、刻板性、温顺性、活跃性。研究发现,圈养马麝个性维度与野生个体的个性类型划分存在差异,主要是受圈养条件和人为干扰等影响。圈养马麝个性量表和五大个性维度的建立对指导马麝繁育管理具有重要实践价值,填补了马麝个性研究的空缺,并为进一步进行麝类动物个性研究奠定了基础。另外,此类个性层次研究方法具有较好区分度,可为其他动物个性的初期研究提供参考。 相似文献
83.
Doreen Gabriel Carsten Thies Teja Tscharntke 《Perspectives in Plant Ecology, Evolution and Systematics》2005,7(2):85-93
Patterns of plant diversity are often related to local site conditions and to competitive interactions, but landscape context may also be important for local plant species richness. This is shown here by analysing the relationship between landscape complexity and local species richness of arable weeds in wheat fields. The fields were located in 18 landscapes characterised by a gradient in landscape complexity from structurally complex to structurally simple (39–94% arable land). We quantified local site conditions, field management intensity and landscape characteristics, and used principle component analyses to ordinate the environmental variables. The percentage of arable land was negatively correlated with perimeter–area ratio, habitat-type diversity and topographical heterogeneity, but landscape characteristics did not correlate with local site conditions and field management intensity. The number of plant species was mainly related to landscape characteristics and to a lesser extent to field management intensity (nitrogen fertilisation), whereas local soil characteristics did not contribute to the explanation of arable weed richness. In a geographic scale analysis using circular landscape sectors ranging from 1 km up to 5 km diameter, the predictive power of landscape complexity for local plant species richness was strongest at 2 km indicating a scale-dependent relationship between landscape context and plant species richness. Our results support the hypothesis that local plant species richness in arable fields is greatly influenced by processes operating at the landscape scale. Seed rain from ruderal source habitats and disturbed edges may be the most important underlying process. 相似文献
84.
Usually the literature on Heliconius show three types of scales, classified based on the correlation between color and ultrastructure: type I – white and yellow, type II – black, and type III – orange and red. The ultrastructure of the scales located at the silvery/brownish surfaces of males/females is for the first time described in this paper. Besides, we describe the ontogeny of pigmentation, the scale morphogenesis and the maturation timing of scales fated to different colors in Heliconius erato phyllis. The silvery/brownish surfaces showed ultrastructurally similar scales to the type I, II and III. The ontogeny of pigmentation follows the sequence red, black, silvery/brownish and yellow. The maturation of yellow-fated scales, however, occurred simultaneously with the red-fated scales, before the pigmentation becomes visible. In spite of the scales at the silvery/brownish surfaces being ultrastructurally similar to the yellow, red and black scales, they mature after them; this suggests that the maturation timing does not show a relationship with the scale ultrastructure, with the deposition timing of the yellow pigment. The analysis of H. erato phyllis scale morphogenesis, as well as the scales ultrastructure and maturation timing, provided new findings into the developmental architecture of color pattern in Heliconius. 相似文献
85.
M. Kraabøl G. Fjeld S. I. Johnsen J. G. Dokk B. K. Dervo J. Skurdal 《Journal of fish biology》2013,82(5):1717-1719
The last of 12 brown trout Salmo trutta stocked in a small pond in south‐east Norway in 1979 were caught in July 2011. These fish represent a curiosity regarding longevity and growth pattern, and ageing from otoliths was consistent with the known life history of this specimen. Despite almost total stagnation in growth since the age of 16 years, the testes were fully developed. 相似文献
86.
长期生态研究中的若干重要问题及趋势 总被引:12,自引:4,他引:12
长期生态研究(LTER)是对生态过程进行长期的监测,研究各种生态因子的相互作用及生态过程,从而揭示出生态系统和环境的长期变化。为生态系统评价管理提供科学依据。本文探讨了长期生态研究的核心问题及其时空尺度,揭示出长期生态所注重的问题及其对策,并以国际长期生态研究计划为例论述了生态研究所关注的内容并提出了研究的发展趋势,这对中国的长期生态研究及陆地生态系统评价有着积极的指导作用。 相似文献
87.
We examined the influence of riparian vegetation on macroinvertebrate community structure in streams of the Upper Thames River
watershed in southwestern Ontario. Thirty-three μ-basins (129–1458 ha) were used to identify land cover variables that influenced
stream macroinvertebrates. Micro-basins represented the entire drainage area of study streams and were similar in stream order
(first, second) and land cover (agricultural or forest; no urban). We described the structure and composition of riparian
vegetation and benthic macroinvertebrate communities at the outflow reach. The nature of the land cover was quantified for
the stream network buffer (30 m) and the whole μ-basin. The objective of this study was to measure the magnitude and nature
of the relationship between the riparian vegetation and benthic macroinvertebrate community at the outflow reach, stream network
buffer, and whole μ-basin scales. Taxon richness (including total number of Ephemeroptera, Plecoptera, and Trichoptera taxa)
and Simpson’s diversity of the macroinvertebrate community all increased with increased tree cover in the riparian zone at
the outflow reach scale. Simpson’s equitability was lower with greater agricultural land cover in the stream network buffer.
No relationship between the macroinvertebrate community and land cover was found at the whole μ-basin scale. Analysis of the
influence of land cover on stream communities within a spatial hierarchy is important for understanding the interactions of
stream ecosystems with their adjacent landscapes. 相似文献
88.
89.
We quantitatively assessed the ability of the gills, caudal fin and scales of the floating goby Gymnogobius urotaenia (Hilgendorf, 1879) (Perciformes: Gobiidae) to serve as substrates for the larvae (glochidia) of the freshwater mussel Sinanodonta japonica (Clessin, 1874) (Unionida: Unionidae) by comparing parasitism success and metamorphosis success. We established three experimental treatments with 10 fish per treatment. Twenty glochidia were introduced onto one of the three body parts of each test fish by direct pipette infestation. Glochidia in the gill group had higher parasitism success than those in the fin and scale groups. Juvenile mussels were obtained only in the gill group. We quantitatively assessed the appropriateness of the three body parts as substrates for glochidia on the basis of three indicators: parasitism success; metamorphosis success; and parasitism and metamorphosis success. We conclude from our laboratory experiment that the artificial introduction of S. japonica glochidia onto G. urotaenia gills is a better procedure for obtaining juvenile mussels than the introduction onto fin or scales. 相似文献
90.
Similarities and differences in intrapopulation trait correlations of co‐occurring tree species: consistent water‐use relationships amid widely different correlation patterns 下载免费PDF全文