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11.
The present research examined continuity and change in the importance of major life goals and the relation between change in goals and change in personality traits over the course of college (N = 298). Participants rated the importance of their life goals 6 times over a 4-year period and completed a measure of the Big Five personality traits at the beginning and end of college. Like personality traits, life goals demonstrated high levels of rank-order stability. Unlike personality traits assessed during the same period and in the same sample, the mean importance of most life goals decreased over time. Moreover, each goal domain was marked by significant individual differences in change, and these individual differences were related to changes in personality traits. These findings provide insights into the relatively unstudied question of how life goals change during emerging adulthood. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
12.
Research suggests that presurgical personality attributes influence postsurgical well-being in both patients and their spouses in the context of coronary artery bypass grafting (CABG) surgery. The authors hypothesized that a spouse's characteristics would influence a partner's psychological well-being, regardless of whether he or she was the patient or the caregiver. In this study, 111 male patients and their caregiver spouses completed measures of neuroticism, optimism, perceived marital satisfaction, and depression prior to elective CABG. Follow-up was conducted at 18 months. As expected, higher caregiver presurgical neuroticism predicted higher patient depressive symptoms at follow-up, with caregiver's concurrent 18-month affect controlled for. Likewise, higher patient presurgical neuroticism predicted higher caregiver depressive symptoms at follow-up. Additionally, higher patient presurgical depressive symptoms and lower presurgical optimism contributed to greater caregiving burden. Relationship satisfaction moderated these effects. These results suggest that partners' personality traits are important determinants of both patients' and their caregiving spouses' well-being. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This study examined the association among caregivers' five-factor personality traits and subjective health with particular emphasis on the role of two theoretically implicated mediators: multi-domain self-efficacy and caregiver strain. The sample comprised 536 informal caregivers (mean age = 62.9 years, SD = 19.9, 72% female, 98% White) of community-dwelling older adults with multiple functional impairments. Both physical health and mental health were negatively associated with neuroticism and positively associated with extraversion and conscientiousness. Agreeableness and openness were associated with better subjective mental health and physical health, respectively. Multiple mediation analyses indicated that self-efficacy mediated all observed associations between personality and subjective health, whereas caregiver strain selectively mediated the associations of neuroticism and agreeableness with mental health. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
15.
应用改良拉裂法,对286份甘蓝型油菜品种(系)进行裂角力测定.结果表明,抗裂角性状在现有甘蓝型油菜品种(系)中存在广泛变异.在146份甘蓝型杂交油菜品种(组合)中,裂角力变异范围0.82~ 2.87N(牛顿),平均裂角力1.83N,变异系数22.11%;裂角力小于1N的有3份(占2.05%),1~2N之间的96份(占65.75%),在2~3N之间的47份(占32.19%),没有检测到裂角力大于3N的品种或组合.在140份甘蓝型常规油菜品种(系)中,裂角力变异范围0.58 ~ 3.47N,平均裂角力1.94N,变异系数31.55%,均高于杂交油菜,其中裂角力小于1N的6份(占4.29%),在1~2N之间的76份(占54.29%),在2~3N之间的49份(占35%),大于3N的9份(占6.42%).与角果和籽粒性状的相关分析表明,油菜角果的裂角力值与单角壳重、单位面积壳重、千粒重达极显著正相关,与每角粒数和角果宽度达到显著正相关.分析杂种与亲本恢复系之间的关系,发现杂种裂角力与恢复系的角果宽度、单角壳重、单位面积壳重、千粒重等性状呈极显著正相关,与粒壳比呈极显著负相关.说明角果大小显著影响油菜的抗裂角特性,角果大、果壳厚、千粒重高等可以作为筛选抗裂角油菜的形态指标.在杂交油菜育种中选用大角大粒恢复系亲本能有效提高杂交油菜的抗耐裂角性.  相似文献   
16.
为给安徽省种植小麦品种的品质利用提供参考,以2016年安徽省小麦产业体系收获的33个小麦品种(系)为试验材料,检测其籽粒品质、面团特性、面包烘焙品质、面粉白度、脂肪氧化酶(LOX)活性和类胡萝卜素含量等。结果表明,33个供试品种(系)间的籽粒品质、烘焙品质、白度、LOX活性等品质性状品种间差异均达极显著;面包表皮质地和形状与LOX活性及b值呈显著正相关;面包芯色泽与面团的稳定时间呈极显著正相关,与弱化度呈显著负相关;平滑度与a值、b值和LOX活性呈显著正相关,与L值及白度呈极显著负相关;纹理结构与b值呈显著正相关;面包总分与面团稳定时间呈显著正相关。本研究在安徽省种植小麦品种中筛选出扬麦23、涡麦182、周麦28、安科157和宿4095等面包评分较高的小麦品种。讨论了安徽种植小麦品种的品质性状及其利用等问题。  相似文献   
17.
Adaptive evolution of dispersal strategies is one mechanism by which species can respond to rapid environmental changes. However, under rapid anthropogenic fragmentation, the evolution of dispersal may be limited, and species may be unable to adequately adapt to fragmented landscapes. Here, we develop a spatially explicit model to investigate the evolution of dispersal kernels under various combinations of fragmentation dynamics and initial conditions. We also study the consequences of modelling an evolutionary process in which dispersal phenotypes continuously and gradually shift in phenotype space in a manner corresponding to a polygenic underlying genetic architecture. With rapid fragmentation rates, we observed the emergence of long-term transient states in which dispersal strategies are not well suited to fragmented landscapes. We also show that the extent and length of these transient states depend on the pre-fragmentation dispersal strategy of the species, as well as on the rate of the fragmentation process leading to the fragmented landscape. In an increasingly fragmented world, understanding the ability of populations to adapt, and the effects that rapid fragmentation has on the evolution of dispersal, is critical for an informed assessment of species viability in the Anthropocene.  相似文献   
18.
Sorghum (Sorghum bicolor) is known as a major feedstock for biofuel production. To improve its biomass yield through genetic research, manually measuring yield component traits (e.g. plant height, stem diameter, leaf angle, leaf area, leaf number, and panicle size) in the field is the current best practice. However, such laborious and time‐consuming tasks have become a bottleneck limiting experiment scale and data acquisition frequency. This paper presents a high‐throughput field‐based robotic phenotyping system which performed side‐view stereo imaging for dense sorghum plants with a wide range of plant heights throughout the growing season. Our study demonstrated the suitability of stereo vision for field‐based three‐dimensional plant phenotyping when recent advances in stereo matching algorithms were incorporated. A robust data processing pipeline was developed to quantify the variations or morphological traits in plant architecture, which included plot‐based plant height, plot‐based plant width, convex hull volume, plant surface area, and stem diameter (semiautomated). These image‐derived measurements were highly repeatable and showed high correlations with the in‐field manual measurements. Meanwhile, manually collecting the same traits required a large amount of manpower and time compared to the robotic system. The results demonstrated that the proposed system could be a promising tool for large‐scale field‐based high‐throughput plant phenotyping of bioenergy crops.  相似文献   
19.
This study focuses on an emerging media multitasking phenomenon called second screening or dual screening. Employing two-wave panel-data from 19 countries, we test whether the Big Five personality traits help explain the use of an additional screen or device while watching political content on TV to discuss the program with others or to look up for additional information. Results show that extraversion positively predicts political second screening. In contrast, agreeableness and openness to new experience are negatively related to political second screening. Moreover, multilevel analysis is performed to test whether the between-country variation is related to economic, political and cultural indicators.  相似文献   
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