基于利益相关者理论的灌溉水价改革研究

从利益相关者的角度探讨灌溉水价改革的相关问题,采用利益相关者理论,对灌溉水价改革的利益相关者进行了定义,分析了传统利益相关者的属性,对关键利益相关者进行了认定,研究了灌溉水价改革驱动下相关利益主体的互作关系及其演变规律,以此提出了灌溉水价改革的相关对策和建议.     

模拟林(竹)-草种植模式遮荫对扁穗牛鞭草的光合速率、生长的影响及其经济效益分析

在模拟遮荫条件下对扁穗牛鞭草的净光合速率、生长指标和经济效益进行了分析。结果表明,扁穗牛鞭草在自然光强1 200μmol/(m2.s)左右时达到饱和点,遮荫48%~79%的光强下很难达到光饱和状态;在中、低光强辐射时,遮荫16%~79%的净光合速率仅为全光下的33.8%~86.4%,高光强辐射下,不同遮荫度下的净光合速率为其全光照的35.0%~94.7%;不同光照强度或者同一光照强度的不同遮荫梯度下,扁穗牛鞭草净光合速率都表现出显著差异[F遮荫=44.09>F0.05(3.84),Pv<0.05;F光照=11.72>F0.05(4.46),Pv<0.05];遮荫改变了光照条件,影响光合产物的合成,进而抑制了扁穗牛鞭草的茎粗生长、植株萌发以及生物量的积累,对株高生长则表现为抑制和促进2个方面;不同遮荫梯度下扁穗牛鞭草产值下降幅度为35.0%~83.1%,年产出0.512 3万元/hm2为扁穗牛鞭草种植的临界值,林(竹)-扁穗牛鞭草模式的冠层遮荫度需等于或小于43%,才能有一定的经济效益。     

重庆雪宝山自然保护区生态安全设计

介绍了重庆雪宝山自然保护区的基本情况、保护区自然资源的主要特色及其科学价值，论述了保护区生态安全设计的指导思想和原则，略述了该设计的主要内容。     

芒属(Miscanthus)植物种质资源研究进展

芒属植物属禾本科多年生高大草类,多分布于热带非洲至亚洲东南部。近年来在欧美国家受到广泛的关注,被认为是一种开发潜力巨大的生物质能源。本文查阅近年国内外相关文献,对芒属植物的生境、分布、遗传多样性、光合特性、抗性生理生化、繁殖学、饲草利用以及作为能源植物的研究等方面做了综述,并展望了其研究前景,旨在推动芒属种质资源的研究。     

Ellagic acid attenuates hypoxic-ischemic brain injury by alleviating autophagy

AIM:To investigate whether ellagic acid (EA) attenuates hypoxic-ischemic encephalopathy (HIE) by down-regulating autophagy. METHODS:In vivo, Sprague-Dawley rats (n=17) were randomly divided into 3 groups:5 rats for sham group, 6 rats for HIE group and 6 rats for HIE+EA pretreatment group. The rats in HIE+EA pretreatment group were treated with EA (10 mg/kg, 10 mL/kg, suspended in corn oil, ig). After 24 h of operation, the rats from each group were sacrificed and their brains were collected. TTC staining and HE staining were used to define the infarct areas and brain structure. The autophagy-related proteins beclin-1, P62, LC3-Ⅱ/-I and Atg5 in the cortex in each group were compared by Western blot. In vitro, PC12 cells were divided into 3 groups:control group, CoCl₂ group and CoCl₂+EA pretreatment group. CoCl₂ at 800 μmol/L was added to the PC12 cells to induce an anoxic environment. The PC12 cells were pretreated with EA at 8 μmol/L and the cell viability was measured by CCK-8 assay. The production of reactive oxidative species (ROS) in the cells was detected by flow cytometry with DCFH-DA staining. MDC staining and TMRE staining were applied to reflect the extent of autophagy and the state of apoptosis, respectively. The autophagy-related proteins in PC12 cells were also investigated. RESULTS:In HIE group, 7-day-old rats were given the operations and the their large infarct areas in the hemisphere were observed by TTC staining. HE staining displayed the injured hemispheres which contained few neurons, and exhibited edema status and serious structural damage. EA pretreatment decreased the infarct area and alleviated the damage to hemisphere with more visible neurons, compared with HIE group. Compared with sham group, the levels of autophagy-related proteins Atg5, beclin-1 and LC3-Ⅱ/-I in the cortex were increased (P<0.01), and P62 protein expression was decreased (P<0.01) in HIE group. Compared with HIE group, the protein expression of Atg5, beclin-1 and LC3-Ⅱ/-I was decreased (P<0.01) and P62 protein expression was increased in HIE+EA pretreatment group (P<0.01). In vitro, compared with CoCl₂ group, the PC12 cells in CoCl₂+EA pretreatment group showed a lower ROS level. Moreover, the cells in CoCl₂+EA pretreatment group exhibited higher mitochondrial membrane potential than that in CoCl₂ group. MDC staining in CoCl₂ group showed high value of fluorescence and increased number of autophagosomes. EA pretreatment reduced the number of autophagosomes and the extent of autophagy to protect PC12 cells. Furthermore, the protein levels of Atg5, beclin-1 and LC3-Ⅱ/-I in CoCl₂ group were higher (P<0.01), and the protein expression of P62 was lower (P<0.01) than those in control group. In CoCl₂+EA pretreatment group, the protein levels of Atg5, beclin-1 and LC3-Ⅱ/-I were decreased (P<0.01) and the protein expression of P62 was increased as compared with CoCl₂ group (P<0.01). CONCLUSION:EA pretreatment attenuates autophagy to protect the neurons against HIE injury.     

吡咯伯克霍尔德氏菌JK-SH007产嗜铁素的相关基因克隆及条件优化

为了明确吡咯伯克霍尔德氏菌Burkholderia Pyrrocinia JK-SH007是否产嗜铁素,揭示其生防机制,本文通过CAS检测该菌株产嗜铁素的能力,并对其嗜铁素合成相关基因cepR进行克隆及序列分析,同时采用单因素试验及响应面法对菌株JK-SH007产嗜铁素条件进行优化。结果表明,菌株JK-SH007具有明显的产嗜铁素能力,其嗜铁素合成相关基因cepR大小为720 bp,与B.pyrrocinia（EU034001）的亲缘关系最近,同源性为99%,两者序列相似性为97%,13个位点出现SNP;另外菌株JK-SH007 cepR基因编码的氨基酸序列有3个氨基酸发生了替换,两者一致性为97%。该菌产嗜铁素最优培养时间是15 h、pH 8、转速200 r/min、最佳碳源和氮源分别是甘油和氯化铵;PB试验筛选出影响该菌株产嗜铁素的关键性因素分别是pH、加碳量、加氮量;CCD试验结果显示,pH和加氮量的交互作用较明显;最终采用Design-Expert软件分析出菌株JK-SH007产嗜铁素最佳方案为碳源加入量15.00 g/L、氮源加入量10.50 g/L、温度30℃、pH 7.36,优化后菌株产嗜铁素能力由18.59提升到37.86,响应面优化产嗜铁素条件的效果是显著的,嗜铁素产量得到明显提高。     

The Efficacy of Mechanical Abrasion and Talc Slurry as Methods of Pleurodesis in Normal Dogs

OBJECTIVE: To determine the efficacy of mechanical abrasion and talc slurry as methods for pleurodesis in normal dogs. STUDY DESIGN: Experimental study. ANIMALS OR SAMPLE POPULATION: Ten normal beagle dogs. METHODS: Group I dogs had mechanical abrasion (MA) of the pulmonary and costal pleurae performed in one hemithorax with a dry gauze sponge with a median sternotomy approach. Group II dogs had 100 mL of a 1 g talc slurry (TS) administered into one hemithorax through a tube thoracostomy. Administration of the TS was visualized by using video thoracoscopy. All dogs were evaluated at 2, 10, 20, and 30 days postoperatively by means of thoracic radiography and ultrasonographic thoracic wall measurement. The dogs were euthanatized 30 days postoperatively and a gross necropsy was performed. Hemithoraces were assigned a pleurodesis score (0-4) and an obliteration grade (0-6). Tissues were collected for histopathologic examination of pulmonary pleura, costal pleura, and pleural adhesions. Pulmonary and costal pleurae were graded for the degree of fibrosis (0-4). RESULTS: Obliteration grade and costal pleural fibrosis score were significantly higher for the treated sides in the MA dogs compared with the TS dogs. MA Dogs: Mechanical abrasion dogs had pleurodesis, obliteration, and pleural fibrosis scores that were greater on the treated side than the untreated side, however, the differences were not statistically significant. Only two MA dogs had firm adhesion of the pulmonary pleura to the costal pleura in portions of the cranial and middle lung lobes in the treated hemithorax. Thoracic wall surface area covered with adhesions was 15% and 21% in each of these two dogs. The median pulmonary pleural fibrosis score of all MA dogs for the treated hemithorax was 3 compared to 0 on the untreated side. TS Dogs: There was no statistical difference for pleurodesis scores and obliteration grades between the treated and untreated sides. No dogs showed evidence of pulmonary to costal pleural adhesions. Histopathology showed talc crossover into the untreated side in all five dogs. Median pulmonary fibrosis score of the treated hemithorax was 1 compared with 0 on the untreated side. CONCLUSIONS: Neither method of pleurodesis produced sufficient pleural adhesions to obliterate the pleural space. It is possible that the degree of pulmonary pleural fibrosis present in MA dogs may be sufficient to limit air leakage from pulmonary blebs and bullae resulting in successful treatment of spontaneous pneumothorax.     

Development and application of plant transformation techniques

Genetic transformation is a powerful biotechnology for introducing novel genes into economically important plants from distantly-related plants or even unrelated species such as microbes and animals.This feat is impossible to be achieved by conventional breeding techniques.Development of transgenic plants has been a controversial subject since 1971 when the first genetically modified organism(GMO)was developed(James and Krattiger1996).Afterwards,transgenic study of plants has sparked     

不同营养添加剂对热应激异育银鲫血液生化指标的影响

为探讨VC、VE和小肽对鱼类抗热应激能力的影响及营养调控作用。本研究选择体重(100±3)g的异育银鲫150尾,随机分成5组,即Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ组。Ⅰ为对照组,饲喂基础日粮,Ⅱ、Ⅲ、Ⅳ和Ⅴ组为试验组,分别饲喂在基础日粮中添加VC制剂100mg/kg、VE制剂100mg/kg、VC制剂100mg/kg VE制剂100mg/kg和1%小肽(替代基础日粮中等量鱼粉)的日粮。常温(25℃)下饲养42d后,将鱼在31℃水中应激24h,随机抽取应激前后3尾鱼血样,测定应激前后血清超氧化物歧化酶(SOD)、乙酰胆碱脂酶(TchE)、谷草转氨酶(GOT)活性。结果表明:在常温养殖条件下,VE组血清TchE活性显著降低(P<0.05),GOT活性显著升高(P<0.05),其他各组鱼血清3种酶活性与对照组相比差异不显著(P>0.05);热应激后,与常温状态相比,添加VC、VE使得SOD活性降低,GOT、TchE活性升高;VC与VE协同作用引起TchE、GOT活性显著上升(P<0.05),SOD活性没有变化;添加小肽能使TchE活性显著升高(P<0.05),SOD、GOT活性不变。与高温对照组相比,VC与VE协同作用组显著提高了SOD、TchE活性(P<0.05);添加小肽可提高SOD活性,降低TchE和GOT活性。由此表明,通过在日粮中补充抗热应激营养添加剂,有助于增强鱼类机体的抗热应激能力;添加小肽以及VC与VE协同作用对缓解异育银鲫热应激损伤具有良好的调控作用。