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41.
有教员力量之大才能有大学力量之大。大学要成就教员力量之大,就必须重视涵养教员方正而理性的人格,必须重视教员学术思想来源的多元性,必须下功夫创设能持续提升广大教员学术素质与能力的环境与机制。  相似文献   
42.
Crop domestication, which gives rise to a number of desirable agronomic traits, represents a typical model system of plant evolution. Numerous genomic evidence has proven that noncoding RNAs such as microRNAs and phasiRNAs, as well as protein-coding genes, are selected during crop domestication. However, limited data shows plant long noncoding RNAs (lncRNAs) are also involved in this biological process. In this study, we performed strand-specific RNA sequencing of cultivated rice Oryza sativa ssp. japonica and O. sativa ssp. indica, and their wild progenitor O. rufipogon. We identified a total of 8528 lncRNAs, including 4072 lncRNAs in O. rufipogon, 2091 lncRNAs in japonica rice, and 2365 lncRNAs in indica rice. The lncRNAs expressed in wild rice were revealed to be shorter in length and had fewer exon numbers when compared with lncRNAs from cultivated rice. We also identified a number of conserved lncRNAs in the wild and cultivated rice. The functional study demonstrated that several of these conserved lncRNAs are associated with domestication-related traits in rice. Our findings revealed the feature and conservation of lncRNAs during rice domestication and will further promote functional studies of lncRNAs in rice.  相似文献   
43.
The impact of river incision induced by channelization and gravel mining on the structure of ground beetle assemblages in riparian habitats was investigated on three montane rivers in southern Poland. Ground beetles were collected on three benches of different elevation in 11 incised and 14 vertically stable cross sections of the rivers. In total, 5821 individuals representing 106 species were collected. The effect of river incision on the diversity and abundance of ground beetles depended on bench height. Only on the lowest bench, inundated about once per year on average, species richness of the assemblages was significantly reduced in incised river cross sections. On this bench, the abundance of the specialists of exposed riverine sediments, i.e. small and medium‐sized predators with high dispersal power and spring breeding strategy, was highly negatively affected by river incision. On the highest bench, large, brachypterous species with spring and autumn breeding strategy, typical of undisturbed habitats, were more abundant in incised cross sections. As this bench is practically not subjected to flooding even in vertically stable cross sections, these species probably benefited from the occurrence of riparian forest along most incised river sections, whereas the riparian areas along vertically stable sections are subjected to higher agricultural pressure. This study shows that in the mountain region where high precipitation helps to maintain moisture of the riparian habitats, river incision has a negative impact only on the specialists of exposed riverine sediments. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
44.
To improve the ecological functioning of riverine ecosystems, large‐scale floodplain rehabilitation has been carried out in the Rhine–Meuse Delta since the 1990s. This paper evaluates changes in abundance of 93 breeding bird species over a period of 10 years in response to rehabilitation, by comparing population changes in 75 rehabilitated sites with 124 non‐rehabilitated reference sites. Such quantitative, multi‐species, large‐scale and long‐term evaluations of floodplain rehabilitation on biodiversity are still scarce, particularly studies that focus on the terrestrial component. We try to understand the effects by relating population trends to ecological and life‐history traits and strategies of breeding birds. More specifically, we try to answer the question whether rehabilitation of vegetation succession or hydro‐geomorphological river processes is the key driver behind recent population changes in rehabilitated sites. Populations of 35 species have significantly performed better in rehabilitated sites compared to non‐rehabilitated floodplains, whereas only 8 have responded negatively to rehabilitation. Differences in effects between species are best explained by the trait selection of nest location. Reproductive investment and migratory behaviour were less strong predictors. Based on these three traits we defined eight life‐history strategies that successfully captured a substantial amount of variation in rehabilitation effects. We conclude that spontaneous vegetation succession and initial excavations are currently more important drivers of population changes than rehabilitation of hydrodynamics. The latter are strongly constrained by river regulation. If rehabilitation of hydro‐geomorphological processes remains incomplete in future, artificial cyclic floodplain rejuvenation will be necessary for sustainable conservation of characteristic river birds. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
45.
以栽培大豆和滩涂野大豆杂交组合(N23674×BB52)亲本及其经逐代耐盐性筛选获得的4个F4∶5家系为研究对象,对其苗期耐盐性、农艺性状、籽粒品质进行了分析和比较。结果表明:F44个株系的农艺性状都介于两亲本之间。盐胁迫下F5株系幼苗的耐盐系数、干物质积累和相对生长速率高于母本栽培大豆N23674,其中4076株系最为突出。籽粒品质较其父本BB52种群有明显改善,主要表现在籽粒中蛋白质和多数必需氨基酸、含硫氨基酸含量及氨基酸总量高于双亲,粗脂肪含量介于双亲之间,且接近于其母本N23674;4076和4111株系亚油酸含量超过双亲。  相似文献   
46.
A collaborative study among three nations (France, Belgium, Netherlands) along the Meuse River developed a consistent approach for collecting and interpreting macroinvertebrate data. Specific mesohabitats were sampled in 16 locations along an 800‐km stretch of this lowland regulated river. The objective was to assess the ‘river health’ using macroinvertebrate communities as indicators of biological and ecological variation in space. The main changes in assemblages were investigated using multimetric and multivariate approaches. The authors examined relationships between faunal variations and both physico‐chemical gradients and man‐made disturbances. We related species traits to faunal changes and habitat characteristics. Both a gradual shift from a macroinvertebrate assemblage dominated by insects to a community dominated by crustaceans and molluscs and a drastic decrease in biotic index values were observed along the longitudinal gradient. Taxa were distributed according to oxygen, nitrate and ammonium concentrations, pH, conductivity and summer hydraulic conditions. But major faunal differences among sites could not be explained simply by physico‐chemical variables. The trait analysis underlined the role of temporary habitats in structuring the summer macroinvertebrate community of sites of the uppermost French sector, which supported the most diverse community in terms of trait combination. Downstream the macroinvertebrate community exhibited a more simple and less stable functional organization. We concluded that the Meuse River exhibited both a high biodiversity and a ‘reasonably good’ water quality in the upper reaches. Two transition zones highlighted the influence of a high degree of human impact on stream integrity. Regulation for navigation, ship traffic and heavily polluted effluent discharges influenced instream conditions via multiple processes determining a decline of both habitat stability and diversity. However, the rare occurrence of habitat‐sensitive species in the lower reaches indicated that a partial recovery of communities may be predicted if restoration and protection of disturbed (especially riparian) habitats are fulfilled. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
47.
Plant communities and dynamics can be characterized according to species composition or plant traits. Here, we used species composition and plant traits to compare their effectiveness in discriminating the biogeomorphological (involving reciprocal feedbacks between physical and biological processes) and ecological (mainly biologically driven) phases of the fluvial biogeomorphological succession (FBS) model. The comparison was done between two French rivers, the largely unchannelized lower Allier and the channelized middle Garonne. One reach representative of each river section was selected for the study. Within each river reach, we chose two contrasted study sites in terms of channel and floodplain dynamics: a reference site (least altered channel and floodplain dynamics) and an altered site (laterally stabilized by riprap and constrained). In the four study sites, we sampled vegetation in 402 plots of 4 m2. The 512 species identified in the plots were characterized in terms of plant traits (20) from a literature review. When comparing reaches in unconstrained ordinations and permutational multivariate analyses of variance, both species composition and plant traits led to a similar identification of the biogeomorphological and the ecological successional trajectories. Nevertheless, the trait approach was less influenced by local and regional bioclimatic, hydrogeomorphological, and anthropogenic settings and thus produced a more comprehensive and general classification of the biogeomorphological and ecological phases of the FBS model. A lower than expected contrast between the four sites was found, because neither species composition nor plant traits could entirely characterize distinct successional trajectories occurring in our reference or altered sites. Furthermore, our results contributed to a better understanding of the multiple successional trajectories that can occur in midlatitude river corridors. It also showed that relating plant traits to their effects on fluvial landform dynamics remains a core challenge in explaining succession including feedback mechanisms between hydrology, morphodynamics, and vegetation dynamics.  相似文献   
48.
An individual's cumulative life decisions help determine that person's well-being. To make good decisions requires knowing something about who one is and who one wants to be. It seems plausible that personality may draw on a specifically tailored intelligence that supports its own self-understanding and contributes to such life decisions. This personal intelligence (PI) helps the individual meet his or her own personal needs and to fit in with (or stand out from) the environment. What are people high in PI actually like relative to those lower in the skills? Drawing on a 2008 theory of PI-related abilities, the author reviews several literatures to examine what features distinguish the behavior of people high in PI from those lower in such skills. The feature list sets the stage for future research in distinguishing high-PI individuals from low-PI individuals according to their life expressions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
49.
The study objective was to investigate whether, compared with nonclinical controls, participants with an avoidant, dependent, or obsessive–compulsive Cluster C personality disorder (PD) manifested reduced levels of memory specificity and whether the association of Cluster C PDs with memory specificity is mediated by repetitive negative thoughts and experiential avoidance. The Autobiographical Memory Test (R. J. McNally, N. B. Lasko, M. L. Macklin, & R. K. Pitman, 1995) was administered along with self-report measures (translated into Dutch) for repetitive, uncontrollable, and negative thinking in the form of worry (Penn State Worry Questionnaire; T. J. Meyer, M. L. Miller, R. L. Metzger, & T. D. Borkovec, 1990) and experiential avoidance (Acceptance and Action Questionnaire; S. C. Hayes et al., 2004) to 294 clinical participants diagnosed with Axis I disorders (assessed with the Structured Clinical Interview for DSM–IV Axis I Disorders [SCID-I]; M. B. First, R. L. Spitzer, M. Gibbon, & J. B. W. Williams, 1994) and Axis II disorders (assessed with the SCID-II; M. B. First, R. L. Spitzer, M. Gibbon, & J. B. W. Williams, 1997)—202 with avoidant, 49 with dependent, and 120 with obsessive–compulsive PD—and to 108 matched nonclinical controls. Participants with a Cluster C PD showed lower levels of memory specificity than did nonclinical controls. Depression and worry mediated the effect of Cluster C PDs on memory specificity. Besides depression severity, repetitive, uncontrollable, and negative thinking may constitute a general mechanism mediating the association of various Axis I and II disorders with memory specificity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
50.
This research has two main purposes. The first is to replicate and possibly to extend the results obtained in a previous study, where the authors found that visitors to the ancient art museum conducted their visit with the primary aim of acquiring understanding and knowledge, while modern art museum visitors conducted their visit with an approach that was primarily emotional and pleasure-seeking. The second purpose relates to studies showing that people who prefer abstract art present higher levels on personality traits like “Openness to Experience” and “Sensation Seeking,” compared to people who prefer realistic art. This study investigates these two personality traits for people who favor visiting museums of ancient rather than modern art. Results confirmed previous findings that emotional aspects related to the visit were relevant for modern art museum visitors, while a more cognitive approach based on learning characterized ancient art museum visitors. Concerning personality traits, no difference was found between the two museum groups on the “Openness to Experience” dimension; differences were found on the “Sensation Seeking” trait; modern art museum visitors attained higher scores as compared to ancient art museum visitors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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