微米木纤维JGD型木橡胶减震器的建模理论研究

选用可再生资源---红松木材的加工剩余物和边角碎料切削而成的木纤维为原料,用数学建模方法构造JGD型木橡胶减震器的外部造型,通过MATLAB验证JGD型木橡胶减震器仿真模型的通用性和精确性。动态输入模型参数,得到不同模型所需的加工尺寸,制作与模型相对应的模具。在模具上完成微米木纤维JGD型木橡胶减震器的整个模压加工过程,既能保证木橡胶减震器外形尺寸,又降低其生产成本,可为微米木纤维JGD型木橡胶减震器的加工系统实际生产提供理论依据。     

竹笋绒茎蝇的研究

竹笋绒茎蝇是毛竹笋根重要害虫,在浙江省一年1代,少数二年1代,以蛹越冬。成虫在 3月份日均气温达12℃以上时羽化,幼虫 4月中旬到 5月下旬为害。被害笋根仅残留 10cm 余,失去吸收及支持作用,增加竹笋退死率,成竹竹杆尖削度大,且容易倒伏。     

育苗基质配方对黄瓜幼苗生理特性的影响

以腐熟菇渣、牛粪为主要原料,研究4种不同配方基质对黄瓜幼苗叶片生理特性和根系活力的影响。结果表明,牛粪、菇渣、草炭、蛭石按体积比2∶2∶4∶2配制的基质中,黄瓜幼苗叶片净光合速率最高,可溶性蛋白和可溶性糖含量显著高于其余处理,叶绿素含量、比叶重、根系活力与传统育苗基质(草炭与蛭石体积比为6.7∶3.3)无显著差异,可代替传统基质用于黄瓜育苗。     

复合保水剂吸水保水性能及其应用

为了促进自制的复合保水剂(以下称复合保水剂)在节水型设施基质栽培中的合理应用,该文比较了复合保水剂和对照保水剂(旱宝贝MP3005KM)的吸水保水性和发芽率,以β-环糊精(β)、羧甲基纤维素钠(CMC)、可溶性淀粉(K)、竹炭粉(Z)和玉米芯热解粉(TD)为原料,采用水浴加热法制备,分析5种保水剂的pH值、溶胀度、吸水速率、失水速率、反复吸水性并进行发芽试验,对结果进行方差分析和多重比较。结果表明:4种复合保水剂性能均优于对照,其中以β-环糊精+羧甲基纤维素钠+可溶性淀粉+玉米芯热解粉配方的复合保水剂为最优,溶胀度达183.98mL/g,吸水速率最大,失水速率最小,发芽指数达对照的7倍。该研究可为中国未来保水剂的研究开发、生产和应用提供参考。     

Establishment of a comprehensive indicator system for the assessment of biodiversity and ecosystem services

Context

Common indicators are needed to monitor biodiversity loss and the implications for the sustainable provision of ecosystem services (ES). A plethora of different sets of indicators may hinder the identification of major endpoints for large-scale assessments of biodiversity and ecosystem services (BES).

Objectives

We aim to describe the main challenges of indicators for BES assessment and provide suggestions for establishing a comprehensive indicator system.

Methods

An extensive literature review was conducted in this study. We review the main challenges of indicators for BES assessment and propose corresponding improvements from our perspectives of theory and practical applications.

Results

The main theoretical challenges of existing indicators include inconsistent definitions and classifications of ES, misunderstanding of linkages among biodiversity, ecosystem structure, functions and services, and practical problems relate to such issues as indicator representativeness, data availability, and uncertainty. Our suggested improvements include clarifying the main terms, concepts and classification of indicators, establishing a robust conceptual framework with clear interactions among different components and indicators, selecting indicators based on ecosystem properties, streaming existing data into one platform, and strengthening validation of proxies. The steps for constructing a comprehensive indicator system for BES assessment are summarized.

Conclusions

Clear definitions of key terms are indispensable to classify indicators and construct a conceptual framework. Improved understanding of the relations among indicators of biodiversity, ecosystem functions, and ES across multiple scales can guide the development of the indicator system. The integrated indicator system is an important tool for BES assessment to support decision making for sustainable development.

     

‘丰香’草莓叶片高效再生体系的建立

 以草莓主栽品种丰香( Fragaria ×ananassa Duch ‘Toyonoka’) 叶片为外植体, 研究了影响组织培养的多个因素, 建立了高效再生体系。结果表明: MS + TDZ 1.5 mg·L ^{- 1} + IBA 0.4 mg·L ^{- 1}培养基最适于不定芽分化。不同滤光膜(绿膜、红膜、蓝膜、黄膜) 对草莓不定芽的分化具显著效应, 绿膜和红膜对芽的分化有明显促进作用, 不定芽再生率达95%以上, 平均每个外植体再生芽数在25个以上; 而蓝膜和黄膜则不利于芽的分化。不同滤光膜光谱差异主要集中在300～700 nm, 红、绿膜在该波段光强较弱,而黄、蓝膜和荧光灯较强。暗处理4周比1、2、3周更有利于提高叶片的不定芽再生率, 此后转到光下培养, 获得的不定芽再生率可达100%。     

热风干制温度对枣果微观组织结构的影响

为了研究热风干制温度对枣果微观组织结构的影响,该试验选用不同温度(35、40、45、50、55℃)热风干制枣果,利用石蜡切片、显微成像技术获得了热风干制过程中不同含水率条件下果肉细胞、空腔等结构参数的分布曲线,借助分布曲线的偏度、峰度(以鲜枣为参照)描述了微观结构参数在热风干制过程中的变化趋势,并建立了微观结构参数(果肉细胞、空腔横截面的面积比、周长比及当量直径比)与宏观干燥参数(水分比)的拟合方程。结果表明,利用微观结构参数分布曲线的偏度、峰度可较好地描述不同温度干制过程中细胞、空腔整体的变化趋势;干制过程中随着含水率的降低,果肉细胞、空腔结构参数的变化趋势均不具有一致性或连续性;不同温度相比之下,低温、高温干制过程对果肉细胞形态的改变均有较大影响,且高温(55℃)条件影响更大;不同温度热风干制过程中,由果肉细胞结构改变所引起的空腔塌缩和扩增同时存在,高温(55℃)条件对空腔的扩增、塌缩影响较大。果肉细胞,空腔结构参数比与水分比之间关系可用非线性模型描述(R2≥0.7283,Std≤25.1682%),模型可预测在不同温度热风干制过程中细胞、空腔随含水率的变化情况,研究结果可为热风干制新工艺的开发提供参考。     

Identification of SNPs in the 5′‐flanking region and 3′‐UTR of the MIH gene and their association with precocity of the Chinese mitten crab Eriocheir sinensis

Moult‐inhibiting hormone (MIH), an important regulator of steroidogenesis, inhibits the synthesis of ecdysteroid in Y‐organ (YO) and plays a significant role in the regulation of moulting and post‐embryonic development of crustacean. Because unsuccessful moulting have been widely observed in precocious crabs, we investigated whether genetic variants in the 5′‐flanking region and 3′‐untranslated region (3′‐UTR) of the MIH gene are associated with precocity of the Chinese mitten crab. Thirty individual DNA samples were sequenced to search for SNPs in the 5′‐flanking region and 3′‐UTR of the MIH gene. Five SNPs (g.196 T>A, g.230 C>T, g.305 T>C, g.323 C>A and g.372 C>T) in the 5′‐flanking region and 6 SNPs (g.2677 C>T, g.2759 T>A, g.2807 T>C, g.3042 A>G, g.3088 T>G and g.3295 T>G) in the 3′‐UTR of the MIH gene were selected for the individual genotyping in a two‐stage association study. We found that a SNP g.3088 T>G in the 3′‐UTR of MIH gene was consistently associated with precocity of the Chinese mitten crab in stage 1 and stage 2, with a per‐allele OR (Odds Ratio) of 1.469 (95% CI: 1.169–1.844) after two stages combined (P = 0.001). However, no significant associations were observed between the other 10 SNPs and precocity of the Chinese mitten crab. To our best knowledge, this is the first association study between various SNP genotypes and phenotype attributes in Chinese mitten crab. Our findings suggest that the SNP g.3088 T>G may be a candidate marker for effective marker‐assisted selection to decrease the precocity of the Chinese mitten crab in future studies.     

浅谈加强农业科研单位的内部控制制度

内部控制制度是单位内部管理制度的重要组成部分,是一种反馈腐败活动的预警装置。做好组织机构、不相容职务的分离、授权批准、财务会计、风险防范的控制并营造和谐的环境、加强内部稽核和审计,能够促进提高经济管理的效率。     

基于GF-3全极化SAR影像多特征优选的水产养殖塘提取

高分三号作为中国首颗民用高分辨率多极化合成孔径雷达卫星,为水产养殖用地监测提供了重要的数据源.为了充分利用GF-3全极化SAR影像,该研究提出了一种基于特征优选的全极化SAR影像养殖塘提取方法.首先通过极化分解和灰度共生矩阵方法共获取了55维特征;然后对影像进行多尺度分割,并利用随机森林-递归特征消除(Random F...