盛中唐诗歌向晚唐过渡的标本——薛逢诗歌论评

薛逢诗歌在唐代诗人中算不上大家和名家，但也算独具面目的一个。薛逢诗歌艺术看似不名一状，难测其端：诗歌风格豪放与英逸交错，诗歌感情基调沉郁与雄浑间杂，诗歌语言浅俗与精警并存。而在其思想和心态表达上：盛世理想主义情怀中渗透衰世感伤，关中士族辉煌自傲中渗透没落烙印，岁月人生反复感慨中渗透个人忧愤。从中可见盛唐的理想主义、中唐的通俗化向晚唐的怀古伤今倾向的转变轨迹。从这个意义上说，薛逢的诗歌艺术形式和思想心态是盛中唐向晚唐过渡的标本，也是时代由盛而衰和诗歌变向的生动写照。     

近交系数计算的程序设计

本文运用字符标记的方法,编制了近交系数计算的程序。利用本程序计算近交系数,不需要对原始系谱整理编码,可将系谱的畜号直接输入计算机处理和运算,使用方便,运算结果准确。本程序可以在 IBM—PC 和 PC—1500微机上运行。     

基于Web的肉羊信息管理系统中亲缘系数及近交系数的程序设计与实现

肉羊计算机辅助育种工作需建立在系统、规范化的羊场生产管理模式下,大量累积数据基础上。本文在肉羊生产管理实现信息化的前期工作基础上,进一步开展育种分析,从近交系数和亲缘系数入手,采用亲缘协方差法,设计程序,按照获取简明系谱、对系谱排序、计算亲缘协方差矩阵三步骤计算。该方法的特点在于无需人工做系谱图,查找共同祖先,绘制通径线,易于计算机编程求解,且与生产管理系统结合可实现全程自动批量运算,简捷、快速,把育种工作者从繁琐的劳动中解放出来,可有效提高育种工作效率。     

基于Excel的个体近交系数直观估算

通过计算畜群内的个体近交系数,可以把握现有畜群的遗传效应,对于畜群的选种选配有着重要的指导意义,能有效地防止近交造成的品种退化等现象。通过Excel函数计算畜群系谱信息中共同祖先出现的次数频率,可简单快速地估算个体间的近交系数,实现近交系数的直观估算,不需要使用者掌握计算机编程知识,可供基层畜牧行业的技术人员参考使用,能快速估算系谱个体的近交情况,使得对群体遗传效应的评估工作极易进行。     

Genetic description of a divergent selection experiment in Angora rabbits with overlapping generations

The chief aims of this paper were the following: (i) to describe the demography and genetic structure in two divergent selected lines for total fleece weight (TFW) of French Angora rabbits with overlapping generations; (ii) to describe the effects of inbreeding during an experiment of divergent selection. A study of longevity with the survival kit showed that there was no significant difference in the risk of death or culling between the low line (LL) and high line (HL). A significant effect of inbreeding (p < 0.05) was observed with a 30% higher risk factor in the highest class of inbreeding coefficient compared with the other classes. The means of generation interval were 562 and 601 days in LL and HL, respectively. The numbers of generations for LL and HL were 3.90 and 3.64, respectively. Generation intervals decreased significantly from 1995 to 2000 (p < 0.05). The number of daughters in HL was very variable. The number of animals per generation was higher in HL than in LL. Each buck left nearly three daughters to the next generation (2.52 in LL, 3.24 in HL). In both lines, the effective number of ancestor genomes still present in the genetic pool of the generation was around eight from the reference population of 1995 to that of 2001. Inbreeding in HL was always higher than in LL. The effect of inbreeding was also significant (p < 0.05) on TFW and live weight. The animals with the lowest inbreeding category produced a higher TFW (p < 0.05) than the others. The observed selection differentials were lower than that expected owing to the breeding animal management rules in order to control inbreeding increase.     

高校大学生抑郁症的成因及预防探析

基于抑郁症的流行病学研究成果,从生物-心理-社会的整合模式分析导致大学生抑郁症的多种病因。针对可能诱发大学生抑郁症的病因,结合党和国家相关政策文件以及心理学相关研究成果,提出构建“医-校-家”三位一体的大学生抑郁症预防体系,实现育心与育德相结合、学校前置预警与医院绿色通道相结合、全员普及教育与特殊重点教育相结合、课堂主渠道与课外主阵地相结合、学校立体育人与家庭联学联动相结合,以期培养高校学生拥有健康的心态。     

Suitability of Canopy Temperature Depression in a Temperate Climate with Drought‐Stressed Winter Rye,Determined with Three Infrared Measurement Devices

Canopy temperature has been recognised as an indicator of crop water status and may thus be a useful secondary trait in selecting for yield under dry conditions. The aim of this study was to test the suitability of canopy temperature depression (CTD = T_air ? T_canopy) in a temperate climate with winter rye, by means of three infrared (IR) temperature measuring devices. In the years 2011 and 2012, 16 winter rye genotypes were examined under drought stress conditions in a rainout shelter and under well‐watered conditions. In each year, the CTD was determined several times during the growth period using two IR thermometers and an IR camera. By means of CTD, it was possible to detect drought stress and to differentiate between water regimes. The three measurement devices showed comparable results, despite greatly different costs. Under drought‐stress conditions, a significant positive correlation between grain yield and CTD was found on most measurement dates in 2011 and on some dates in 2012. When the CTD was pooled across water regimes, a significant positive correlation between grain yield and CTD was obtained on every measurement date. However, as genotypic differences for CTD were non‐existent, the correlations are less meaningful. The missing genotypic differences for CTD were rather caused by the limited genetic variability of the genotypes used in this study, than by climatic conditions. Due to this limitation, we were not able to make a concluding statement about the CTD in a temperature climate, although the results are quite promising and indicate that the CTD can potentially be used in a temperate climate.     

Relationship between inbreeding and milk production traits in two Italian dairy sheep breeds

The effects of inbreeding in livestock species breeds have been well documented and they have a negative impact on profitability. The objective of this study was to evaluate the levels of inbreeding in Sarda (SAR, n = 785) and Valle del Belice (VdB, n = 473) dairy sheep breeds and their impact on milk production traits. Two inbreeding coefficients (F) were estimated: using pedigree (F_PED), or runs of homozygosity (ROH; F_ROH) at different minimum ROH lengths and different ROH classes. After the quality control, 38,779 single nucleotide polymorphisms remained for further analyses. A mixed-linear model was used to evaluate the impact of inbreeding coefficients on production traits within each breed. VdB showed higher inbreeding coefficients compared to SAR, with both breeds showing lower estimates as the minimum ROH length increased. Significant inbreeding depression was found only for milk yield, with a loss of around 7 g/day (for SAR) and 9 g/day (VdB) for a 1% increase of F_ROH. The present study confirms how the use of genomic information can be used to manage intra-breed diversity and to calculate the effects of inbreeding on phenotypic traits.     

Phenotypic variation and correlations between monoploids and doubled monoploids of Solanum phureja

Summary Ten anther-derived monoploids, twelve doubled monoploids and the heterozygous anther donor clone of Solanum phureja were compared for six vegetative, eight reproductive and three yield characters in the greenhouse. Significant high correlations were observed between the monoploids and their doubled monoploids for 14 of 17 characters. Therefore, doubled monoploids presumably express the same alleles as monoploids and the phenotypic expression of a monoploid can be used to predict accurately the phenotype of the derived doubled monoploid. Doubled monoploids flowered earlier and had significantly higher values than the monoploids for 15 of 17 characters, indicating a positive effect of increasing gene dosage from monoploid to diploid. Morphological traits can be used to distinguish plants of the two ploidy levels. Significant differences among clones were observed for all parameters within each ploidy level. The anther donor was not significantly different from the mean of doubled monoploids for 10 of 17 characters. For each of 14 characters, some doubled monoploids exceeded the anther donor. Therefore, doubled monoploids which do not express homozygote depression can be obtained.     

鹅掌楸属树种近交衰退分析

异交物种易发生近交衰退。为了研究濒危树种鹅掌楸天然种群的濒危机制,以鹅掌楸属树种4种人工交配类型(种间杂交、种内杂交、回交、自交)子代为材料,从表型(种子饱满度、出苗率、苗期生长量)和基因型(SSR位点)两方面分析了鹅掌楸近交衰退状况。结果表明:子代饱满度、出苗率有相同的变异趋势,种内杂交>种间杂交>回交>自交。子代苗期生长量为种间杂交>回交>种内杂交>自交。子代纯合子比率为自交>种内杂交>回交>种间杂交,表明鹅掌楸属树种近交衰退明显。同时还发现北美鹅掌楸基因杂合度高于鹅掌楸。