大众化教育背景下大学生就业心态调查与分析     

许晓辉 《高等农业教育》2011,(1):85-87,91

通过因子分析技术,探寻大学生就业心态的结构。通过比较不同群体在就业心态的各因素间的差异,了解各个群体的特殊性,以便对大学生就业进行有效的管理与预防,加强就业指导的针对性和实效性,帮助学生进行合理的认知调节,提高大学生的就业率和就业质量。  相似文献   

稀有植物喜荫草种群结构及所在群落结构特征     

陈焕强  余传文  王朝勇  郑景苏  莫锦华  许涵  李意德 《热带林业》2010,38(4):29-31

文章对我国热带地区出现的稀有植物喜荫草S.tenella Bl.的种群结构及其所在群落结构特征进行描述。结果表明喜荫草在野外出现的频度较小,不易于被发现;但其种群结构较为稳定,更新良好。而且,喜荫草种群所在群落存在一定数量的本土特有种和保护植物,喜荫草能与它们良好的共生,它主要生长区域集中在尖峰岭自然保护区的范围内,得到良好的保护。  相似文献   

风景园林本科课程体系中“场地认识与分析”课程的引入     

张善峰  许大为 《高等农业教育》2010,(7):49-52

风景园林学科研究范围、操作范围的拓展,学科研究深度、操作深度的发展,对风景园林专业人才的培养提出了更高的要求。针对当前专业教育在课程设置和教育方式存在的问题,尝试引入新的专业课程以完善学生专业知识和专业能力,使学生具备提出科学合理、技术可行、功能合适、表现适当的环境解决方案的能力。  相似文献   

冰雪灾害后南岭常绿阔叶林受损优势种萌条特性   总被引：1，自引：0，他引：1  

王旭  黄世能  李家湘  吴仲民  周光益  张守攻  沈孝清  刘新科 《林业科学》2010,46(11)

在南岭冰雪灾害受损常绿阔叶林建立4块样地,分析样地内受损树木的受损类型、径级、树种组成等因子与灾后萌条关系,结果表明:1)灾害后受损优势木72.00%以上均有萌条出现,乔木层优势木萌条率高于灌木层,为南岭地区冰雪灾害后受损森林生态系统快速恢复与重建提供保障;2)不同受损优势木萌条率存在差异,萌条率随着受损程度的增加呈增加的趋势,其中倒伏类型萌条率最高(100%),其他受损类型中灌木层金缕梅科萌条率最低,乔木层樟科萌条率最低;3)冰雪灾害后萌条特性表现出与采伐、刀耕火种后不同的规律,应做为1个特例进行研究;4)建议在我国亚热带地区森林自然干扰频发区,在人工促进恢复时多选用格药柃、小红栲和交让木等,有利于各层次结构与组成的保持.  相似文献   

抗球虫药新剂型的制备与研究     

底佳芳  徐恩娟  聂月美  陈贵才 《饲料工业》2012,33(6):35-37

采用固体分散技术,利用溶剂法,以处方比例马度米星铵:聚维酮(聚乙烯吡咯烷酮,PVPk30)分别为1:1、1:2、1:3制备了3个马度米星铵固体分散体,通过差示扫描量热法(DSC)分析鉴定,当马度米星铵与PVP k30的比例为1:3时马度米星铵的药物特征吸热峰消失,说明固体分散体制备成功。对药物进行体外累积溶出度研究,结果马度米星铵固体分散体在60 min内体外累积溶出度可达98.46%,比马度米星铵预混剂的2.57%提高了38倍多。抗球虫效果研究表明,马度米星铵固体分散体的抗球虫指数(ACI)为197.7,明显高于ACI为191.8的马度米星铵预混剂。  相似文献   

不同激素处理对非洲菊开花的影响     

刘旭  刘博  吕春华  陈芬  罗桂杰  王昊 《北方园艺》2012,(24)

以“玲珑”非洲菊为试材,研究了不同浓度的赤酶素、激动素和二者混合液对非洲菊开花的影响.结果表明:三者均能影响非洲菊开花时间和开花质量,50 mg/L的赤霉素处理和赤霉素200 mg/L+激动素200 mg/L处理效果最佳,使非洲菊产花量及切花质量显著高于对照(清水),并且缩短开花时间.  相似文献   

Atorvastatin inhibits IL-1β and IL-18 releases via lowering the expression of NLRP1 inflammasome     

YU Si-yang  WANG Yan  ZENG Gao-feng  LIU Yang  XU Jian-qiang  ZENG Meng-ya  TANG Ye-hua  ZENG Zhi-ying  SHI Xiao-qiao  CHEN Ying  ZHAO Guo-jun 《园艺学报》2016,32(5):863-868

AIM: To explore the role of nucleotide-binding oligomerization domain-like receptor protein 1 (NLRP1) inflammasome in atorvastatin-induced reduction of interleukin-1β (IL-1β) and interleukin-18 (IL-18) releases from the THP-1 macrophages. METHODS: Lipopolysaccharide (LPS, 10 μg/L) was used to trigger the secretion of IL-1β and IL-18 in the THP-1 macrophages. The cells were incubated with different concentrations of atorvastatin (1, 10 and 20 μmol/L) for 24 h, or treated with 10 μmol/L atorvastatin for different time (12 h, 24 h and 48 h). NLRP1 siRNA was transfected into the THP-1 cells. The mRNA expression of NLRP1 inflammasome was detected by RT-PCR. The protein expression of NLRP1 inflammasome was determined by Western blot. The secretion of proinflammatory cytokines IL-1β and IL-18 was quantified by ELISA. RESULTS: Atorvastatin inhibited the mRNA and protein expression of NLRP1 inflammasome in the THP-1 macrophages in a dose- and time-dependent manner. Transfection of NLRP1 siRNA significantly decreased the protein expression of NLRP1 and promoted the suppressive effect of atorvastatin on IL-1β and IL-18 secretion in the THP-1 macrophages. CONCLUSION: Atorvastatin inhibits the production of IL-1β and IL-18 in the macrophages through decreasing NLRP1 inflammasome expression, possibly contributing to the anti-inflammatory effect of atorvastatin on atherosclerosis.  相似文献   

High‐throughput Cryopreservation of Sperm from Sex‐reversed Southern Flounder,Paralichthys lethostigma          下载免费PDF全文

E Hu  Rafael Cuevas‐Uribe  Huiping Yang  Robin Sanderson  Adriane O. Gill  Harry Daniels  Terrence R. Tiersch 《Journal of the World Aquaculture Society》2016,47(4):555-565

The Southern flounder, Paralichthys lethostigma, is a valuable aquaculture fish with established markets in the USA. All‐female production in this species is an important technology for aquaculture because the females usually have body sizes twice those of males at the same age, and sex‐reversed males (genotypic XX neomales) are used for all‐female production by crossing with genetically normal females. However, sperm volume from the neomales is usually small (<0.5 mL) and limits their application for all‐female fish production. Cryopreservation of sperm from these sex‐reversed neomales will provide access on demand with increased efficiency to extend the application of neomales. The goal of this study was to develop a protocol for cryopreservation of sperm from the Southern flounder by using an automated high‐throughput processing system. The objectives were to: (1) determine the effect of osmolality on activation of sperm motility; (2) evaluate the effect of extender solutions on sperm motility capacity; (3) evaluate the acute toxicity of cryoprotectants (dimethyl sulfoxide [DMSO], propylene glycol, and polyethylene glycol) on sperm motility, and (4) estimate the effect of cooling rate on sperm cryopreservation and post‐thaw fertilization. Sperm motility was activated when osmolality was 400 mOsmol/kg or higher. Of the three extender buffers tested, HEPES4‐(2‐hydroxyethyl)‐1‐piperazineethanesulfonic acid (HEPES) at 300 mOsmol/kg resulted in better protection for sperm motility than did Hanks' balanced salt solution and Mounib solution at 300 mOsmol/kg during 7 d of refrigerated storage. After 30 min equilibration with the cryoprotectant of 15% DMSO, sperm motility was 24 ± 21% (fresh sperm motility without any cryoprotectants was 42%). After cooling at a rate of 20 C/min, post‐thaw sperm motility was 8 ± 5% and fertilization was 63 ± 40% evaluated at the 32–64 cell stage (5 × 10⁵ sperm per egg). Overall, a protocol was developed for sperm cryopreservation in the Southern flounder with high‐throughput processing, which provides a tool to preserve the valuable genetic resources from neomale flounders, and enables germplasm repository development for the Southern flounder.  相似文献   

Molecular characterization,tissue distribution,and expression regulation from fasting and re-feeding of two growth hormone receptors in mandarin fish Siniperca chuatsi     

Xue Lu  Yongming Gu  Xiaocui Hou  Haifang Wang  Pengfei Wang  Peng Xu  Lei Zeng  Lei Zhou  Guifeng Li 《Fisheries Science》2016,82(1):155-169

  相似文献   

麻核桃果实性状的变异及相关分析     

陈梦华  史薪钰  刘洋  韩飞腾  李保国  张雪梅 《北方园艺》2016,(2):6-11

以"满天星"、"苹果园"、"大官帽"等7个麻核桃品种为试材,对其青果的单果重、横径、纵径、果形指数以及坚果的单果重、横径、纵径、侧径、果形指数、三径均值进行了变异和相关分析,以期为麻核桃种植户、青果采购商在品种选择时提供参考依据。结果表明:在青果性状方面,"大官帽"的单果重和横径分别为109.01g和6.01cm,"承德官帽"的纵径为5.79cm,"满天星"的青皮厚度为1.17cm,均高于其它品种;"四座楼"单果重、纵径和青皮厚度的变异幅度分别为29.30g、0.63cm和0.29cm,变异系数分别为9.43%、3.63%和10.43%,"承德官帽"和"白狮子头"果形指数的变异幅度分别为0.11和0.11,变异系数分别为3.07%和3.97%,均低于其它品种。在坚果性状方面,"大官帽"的单果重、纵径、横径、侧径及三径均值分别为33.47g、4.47cm、4.69cm、4.39cm和4.52cm,均高于其它品种;"四座楼"和"苹果园"单果重、纵径及三径均值的变异幅度分别为9.00g、0.43cm、0.55cm和9.00g、0.44cm、0.45cm,变异系数分别为11.26%、3.91%、4.24%和12.09%、3.48%、4.00%,"四座楼"果形指数的变异幅度为0.13,变异系数为4.66%,均低于其它品种。青果和坚果性状的相关分析表明,青果单果重与坚果的单果重和横径呈显著正相关,与坚果的纵径和三径均值呈极显著正相关;青果纵径与坚果果形指数呈显著正相关,与坚果纵径呈极显著正相关;青皮厚度与坚果纵径呈极显著正相关。  相似文献