河西走廊苜蓿产业的可持续发展

从土资源状况，种植业和结构调整，生态环境建设、饲料工业及畜牧业发展，市场经济发展的需要５个方面论述了河西走廊苜蓿产业可持续发展的潜力，并提出了苜蓿产业发展的思路、对策及措施。     

蚕学专业"互联网+"教学改革初探及调查分析

为了探索新型教学体系,拓展学生实践教学活动,以蚕学专业课程体系中的代表课程为例,建设"互联网+"教学资源,组建教学队伍和创新"互联网+"教学评价体系.通过"互联网+"网络课程教学实践1年后,对105名本科学生进行问卷式调查,从学生对网络课程的需求、认知、务件、意见反馈和实际教学效果等方面分析了基于互联网的教学模式与传统课堂教学的优势和弊端,以期促进蚕学专业本科教学质量不断提升.结果 显示,学生具有网络教学配合和补充课堂教学的需求,具备通过网络教学进行学习的条件,但由于蚕学课程大多专业实践性很强,学生更愿意接受线上线下的混合式教学模式和翻转课堂教学形式,而且这两种教学方式更有利于教师对教学效果的掌控,更有利于学生巩固基础知识,形成系统的知识和技能,网络教学可以作为辅助教学方式.     

Climate and groundwater recharge during the last glaciation in an ice-covered region

A multitracer study of a small aquifer in northern Switzerland indicates that the atmosphere in central Europe cooled by at least 5 degreesC during the last glacial period. The relation between oxygen isotope ratios (delta18O) and recharge temperatures reconstructed for this period is similar to the present-day one if a shift in the delta18O value of the oceans during the ice age is taken into account. This similarity suggests that the present-day delta18O-temperature relation can be used to reconstruct paleoclimate conditions in northern Switzerland. A gap in calculated groundwater age between about 17,000 and 25,000 years before the present indicates that during the last glacial maximum, local groundwater recharge was prevented by overlying glaciers.     

家蚕突变型第2煤色(so2)的遗传学研究

家蚕第2煤色(so2)发掘于西南大学家蚕基因资源库保存的16-111系统,其主要特征为:幼虫体表污灰色,蛹色黝黑.其它性状均正常.遗传分析结果:第2煤色(so2)对正常型为隐性,单基因突变;是相似性状突变型煤色(so)的等位基因,对煤色(so)为显性.因此,家蚕第26号染色体上该基因座的3个等位基因间的显隐性关系为:+＞so2＞so.

Abstract：

"Sooty 2" (so2) has been discovered in silkworm strain 16-111 conserved in the Silkworm Re-source Bank at Southwest University. It is characterized by dirty grey colored body surface of the larva andblack-skin pupa. The other traits are all normal. Genetic analysis shows that it is controlled by a single re-cessive mutant gene. It is the allele of sooty(so)with similar characters, and so2 seems to be dominant toso. Therefore, the dominant-recessive relationship of the 3 alleles at the locus on the 26 th chromosome insilkworm is +＞so2＞so.     

Apoptosis‐Related Protein Expression During Pre‐ and Post‐Natal Testicular Development After Administration of Glucocorticoid in utero in the Sheep

Pre‐natal glucocorticoids are used in women at risk of preterm delivery to induce foetal lung maturation. However, glucocorticoids can produce negative outcomes for other tissues such as the reproductive system. We therefore tested the effects of pre‐natal betamethasone on testicular morphology and apoptotic protein immune expression during pre‐ and post‐natal development. Pregnant ewes (n = 42) bearing singleton male foetuses were randomly allocated to receive intramuscular injections of saline or betamethasone (0. 5 mg/kg) at 104, 111 and 118 days of gestation (DG). Testes were collected at 121 and 132 DG, and at 45 and 90 post‐natal days (PD) and subjected to morphometric analysis (volume densities of sex cords and interstitial tissues; sex cord diameter). Immunohistochemistry (% stained area) was used to assess active caspase‐3, Bax, Bcl‐2 and cell‐cycle proteins (PCNA). Compared with control values, betamethasone treatment decreased sex cord diameter at 121 DG, 45 and 90 PD, and sex cord volume at 90 PD. Active caspase‐3 was decreased by betamethasone at 121 DG and 90 PD, but Bax was increased in all betamethasone groups. Bcl‐2 and PCNA decreased in the betamethasone groups at 121 DG and 45 PD, but increased at 132 DG and 90 PD. We conclude that high levels of pre‐natally administered glucocorticoid reduce foetal testicular development, perhaps via changes in the balance between pro‐ and anti‐apoptotic proteins and cell‐cycle proteins. These outcomes could compromise the future spermatogenic potential of male offspring.     

民勤绿洲沙地系统特征及"退耕"建议

以民勤绿洲退耕地为研究对象,从民勤绿洲耕地退耕背景及特点出发,阐述了民勤绿洲沙地系统特征,并提出了退耕地生态恢复建议.认为民勤绿洲沙地系统存在水资源短缺、林牧业用地比例偏低、农业用地面积与水资源活动紧密相连的特点;民勤耕地退耕是当前水资源危机解决的关键.退耕地生态治理的意义在于变退耕地生态恢复区为新的防风阻沙林区,从而加强绿洲防护,也充当了减少水资源利用的生态减压区角色,更调节了当地农业产业结构和行业结构;提出有顺序条理化退耕,重点治理风沙口退耕地,退耕前采取植被恢复措施,政府制定、协调退耕地植被恢复各项工作的建议.     

野油菜黄单胞菌XC3813-3815基因启动子的定位分析

野油菜黄单胞菌野油菜致病变种（简称Xcc）是十字花科作物黑腐病的病原菌,同时也是发酵工业生产黄原胶的菌种。在以前的工作中,证实了Xcc8004菌株基因组中一个包含XC3813-3815三个基因的新位点与致病性和胞外多糖（EPS,又称黄原胶）合成有关。本工作通过PCR合成包含相应ORF及其上游不同长度的DNA片段,并克隆于不带启动子的质粒载体pLAFR6后,将所获的重组质粒互补相应的突变体。通过这一功能互补的方法,确定了这三个基因在其ORF上游约50bp内分别拥有自身的启动子。     

Cloning and Characterization of Boar Epididymal Secretory Proteins by Homology to the Human

Northern blot analysis suggested that the boar epididymis produces closely related counterparts to human epididymal proteins HE1, HE3, HE4, HE5 and HE12. ‘Full‐length’ cloning by nucleic acid and amino acid sequence similarity was achieved by RT‐PCR methods in the case of the porcine counterparts of HE3 and HE4, while the homologues of HE5 and HE12, despite their cross‐hybridization during Northern blot analysis, have not yet been cloned. The two novel porcine cDNAs were derived from moderately abundant epididymal mRNAs that were 75 and 83% identical to HE3 and HE4 cDNAs, respectively. To emphasize their relationship to the corresponding HEs, they were named Se3 and Se4 cDNAs. Their open reading frames predicted small secretory proteins with 55% (Se3) and 76% (Se4) conserved amino acids. Monospecific antipeptide antibodies to HE secretory proteins identified He3‐ and HE12‐related proteins on Western blots of porcine epididymal fluid and semen. Both Northern and Western analyses indicated that the Se proteins were produced in a regionalized pattern and accumulated in the cauda fluid.     

Effect of growth differentiation factor‐9 (GDF‐9) on the progression of buffalo follicles in vitrified–warmed ovarian tissues

To improve the reproductive performance of water buffalo to level can satisfy our needs, the mechanisms controlling ovarian follicular growth and development should be thoroughly investigated. Therefore, in this study, the expressions of growth differentiation factor‐9 (GDF‐9) in buffalo ovaries were examined by immunohistochemistry, and the effects of GDF‐9 treatment on follicle progression were investigated using a buffalo ovary organ culture system. Frozen–thawed buffalo ovarian follicles within slices of ovarian cortical tissue were cultured for 14 days in the presence or absence of GDF‐9. After culture, ovarian slices were fixed, sectioned and stained. The follicles were morphologically analysed and counted. Expression pattern of GDF‐9 was detected in oocytes from primordial follicles onwards, besides, also presented in granulosa cells. Moreover, GDF‐9 was detected in mural granulosa cells and theca cells of pre‐antral follicles. In antral follicles, cumulus cells and theca cells displayed positive expression of GDF‐9. In corpora lutea, GDF‐9 was expressed in both granulosa and theca lutein cells. After in vitro culture, there was no difference in the number of primordial follicles between cultured plus GDF‐9 and cultured control that indicated the GDF‐9 treatment has no effect on the primordial to primary follicle transition. GDF‐9 treatment caused a significant decrease in the number of primary and secondary follicles compared with controls accompanied with a significant increase in pre‐antral and antral follicles. These results suggest that a larger number of primary and secondary follicles were stimulated to progress to later developmental stages when treated with GDF‐9. Vitrification/warming of buffalo ovarian tissue had a little remarkable effect, in contrast to culturing for 14 days, on the expression of GDF‐9. In conclusion, treatment with GDF‐9 was found to promote progression of primary follicle that could provide an alternative approach to stimulate early follicle development and to improve therapies for the most common infertility problem in buffaloes (ovarian inactivity).     

QTL Detection and Epistasis Analysis for Heading Date Using Single Segment Substitution Lines in Rice(Oryza sativa L.)

Heading date of rice is a key agronomic trait determining cultivated areas and seasons and affecting yield. In the present study, five primary single segment substitution lines with the same genetic background were used to detect quantitative trait loci(QTLs) for heading date in rice. Two QTLs, q HD3 and q HD6 on the short arm of chromosome 3 and the short arm of chromosome 6, respectively, were identified under natural long-day(NLD). Nineteen secondary single segment substitution lines(SSSLs) and seven double segments pyramiding lines were designed to map the two QTLs and to evaluate their epistatic interaction between them. By overlapping mapping, q HD3 was mapped in a 791-kb interval between SSR markers RM3894 and RM569 and q HD6 in a 1 125-kb interval between RM587 and RM225. Results revealed the existence of epistatic interaction between q HD3 and q HD6 under natural long-day(NLD). It was also found that q HD3 and q HD6 had significant effects on plant height and yield traits, indicating that both of the QTLs have pleiotropic effects.