Changes of enzyme activity and hematopoiesis in Chinese prawn Fenneropenaeus chinensis (Osbeck) induced by white spot syndrome virus and zymosan A

White spot syndrome virus and zymosan A were used to stimulate the Chinese prawn Fenneropenaeus chinensis (Osbeck), and enzyme activities in organs involved in immune defence e.g., lymphoid organ, hepatopancreas and gill, total haemocyte count and mitotic index of haematopoietic tissue (HPT) were measured. The results showed that activities of phenoloxidase (PO), superoxide dismutase (SOD), alkaline phosphatase (ALP) and acid phosphatase (ACP) were higher in lymphoid organ than in gill. The hepatopancreas had no PO activity, its SOD activity was similar to the lymphoid organ, and its ALP and ACP activities were higher than lymphoid organ and gill. Phenoloxidase activity in lymphoid organ was higher than that of the control group at 2 h after injection and lower than control after 24 h. Superoxide dismutase activity in all organs showed an increase. Alkaline phosphatase activity in lymphoid organ and gill was higher than that of the control group at 2 and 24 h after injection respectively. The difference in ACP activity was not significant. After injection with zymosan A, the mitotic index of HPT increased by 1.5‐fold compared with the control, and returned to control level after 48 h.     

Chlorogenic acid attenuates inflammation,oxidative stress,apoptosis and protects head kidney macrophage of yellow catfish from ammonia toxicity

Ammonia is the most common contaminants found in aquaculture water that seriously endangers fish health. However, there are few studies on the strategy and mechanism on alleviating ammonia toxicity in fish. The current study aimed to observe the cytotoxic effects of ammonia and the protective effects of chlorogenic acid (CGA) on head kidney macrophage of yellow catfish from the perspective of inflammation, oxidative stress and apoptosis. The cells were randomized into normal control, ammonia group (0.23 mg L^?1), CGA group (125 µmol L^?1), CGA (5, 25, 125 µmol L^?1) + ammonia (0.23 mg L^?1) groups. Cells were pretreated with CGA for 1 h followed by ammonia for 24 h. Findings suggested that ammonia treatment reduced cell viability, increased ROS production, up-regulated antioxidant (SOD, GPx) and pro-inflammatory (TNF-α, IL-1, IL-6, COX-2, NF-κB p65) genes expression, down-regulated the mRNA levels of M2-type macrophage marker (Arg-1) and anti-apoptosis (Bcl-2), and CGA attenuated the toxic effects of ammonia. The findings may provide insight into the underlying mechanisms of ammonia toxicity and suggest that CGA can be used as a potential natural supplement to alleviate ammonia toxicity in fish.     

一种基于NFC的农产品溯源系统

传统的RFID和二维码农产品溯源系统需要专门的阅读设备才能查询农产品溯源信息,用户使用不便,造成产品推广、普及困难。本文结合智能手机中的NFC模块,提出一种基于NFC的农产品溯源系统,可以通过智能手机查询农产品溯源信息。系统改进溯源信息存储位置、存储方式和存储权限,提高农产品溯源信息的可靠性、公正性和真实性,并采用B/S架构,可以兼容多种硬件平台和操作系统。     

盘式吸渗仪测定土壤导水率的两种新方法

应用盘式吸渗仪测定田间土壤导水率具有快速简单的优点，但是测定结果的计算处理比较繁琐，寻求简单的计算方法是广泛应用盘式吸渗仪的关键问题。该文改变盘式吸渗仪测定土壤导水率的三维入渗过程为一维入渗过程，简化了测定结果的计算处理。结果显示：两种不同的一维入渗过程达到的稳定入渗率和导水率之间有很好的线性关系，但是三维过程计算的导水率大于一维过程。双套盘吸渗仪一维过程计算导水率与稳定入渗率一致性较好，但是和三维稳态、瞬态方法计算结果之间差异明显，因此在应用这些方法时需要适当调整参数，建议使用双套盘吸渗仪快速测定田间土壤导水率。     

黄河泥沙充填复垦中土工布排水拦沙效果的模拟试验

为验证土工布用于加速引黄河泥沙充填采煤沉陷地的后期侧向排水及降低排水中泥沙含量的效果,在室内进行了基于土工布的泥沙充填排水模拟试验。该试验在玻璃槽内完成,设计3个试验处理,分别为ZT-250(整个断面开口+铁丝网+ZW-250土工布)、ZT-300(整个断面开口+铁丝网+ZW-300土工布)以及CK(断面中间部分开口+可调节高度的塑料板)。测定了3个处理的排水含沙量及泥沙粒径、玻璃槽内表层泥沙粒径以及充填表层和底层泥沙含水率随时间的变化。结果表明:1)3种处理排水含沙量整体差异较小,但使用土工布处理的排水含沙量随时间的延长逐渐降低,而对照处理排水含沙量随时间的延长逐渐增大;2)排水初期和中期,对照CK的排水中泥沙的黏粒含量均高于使用土工布的2个处理。排水后期CK的黏粒含量介于处理ZT-250和ZT-300之间。随着试验的进行,使用土工布的2个处理排水中泥沙的黏粒含量逐渐升高,粉粒含量逐渐降低,而对照处理呈现相反的变化趋势。使用土工布的2个处理拦沙效果较为稳定。3)3种处理充填表层泥沙粒径级配无明显差异,但使用土工布处理充填的表层泥沙的极细砂粒含量较高。4)3种处理充填泥沙表层和底层含水率变化存在差异,使用土工布可以加速泥沙中过饱和水的排除,其中处理ZT-250排水效果最好。该研究可为中国东部高潜水位平原矿区采煤沉陷地引黄河泥沙充填复垦的快速排水工艺革新提供依据。     

不同施肥条件下农田硝态氮迁移的试验研究

NO^-₃-N的淋失是旱地农田氮素损失的重要途径之一，也是引起地下水污染的一个主要原因。在黄土高原地区，夏玉米生长正逢雨季，是NO^-₃-N淋失的主要时期。该研究基于阻水层理论和黄土高原地区传统的垄作习惯，在手工模拟机具成垄压实施肥的基础上研究了该施肥法与传统的平地施肥、垄沟施肥(成垄不压实)条件下土壤NO^-₃-N的迁移动态，结果表明，在供水量相同条件下，由于平地和垄沟条件下水分分布的差异，导致平地土壤中的NO^-₃-N较垄沟耕作易于迁移。在生育前期，由于作物根系对NO^-₃-N的吸收和拦截，成垄压实与成垄不压实施肥对阻止NO^-₃-N随水下移差异不大；生育后期，当作物需肥量减小时，成垄压实施肥能够阻止NO^-₃-N向深层土壤迁移累积。玉米收获后，3种施肥方式下土壤NO^-₃-N迁移深度为平地(>60 cm)>垄沟施肥(>45 cm)>成垄压实施肥(＜35 cm)。     

多孔介质溶质运移边界层理论初探

研究了溶质运移边界层条件和边界层运动方程。采用一个小的运移通量脉冲定义边界层应满足的特征值。应用加Ｌａｐｌａｃｅ变换方法求解边界层问题的浓度解，并推导出边界层运动方程。边界层问题浓度解与精确解比较表明在计算浓度方面误差很小。边界层运动方程的一个重要应用是估算溶质运移参数。这个估算参数的新方法是应用边界层随时间运动的观测信息。这个方法简单，节省时间，并能充分利用边界层运动观测资料。     

Mineralogy of Inhalable Particulate Matter (PM10) in the Atmosphere of Beijing, China

The study of mineral components in respirable particles (particulate matter with diameter less than 10 μm, PM₁₀) in ambient air is important in understanding and improving air quality. In this study, PM₁₀ samples were collected in various areas around Beijing during 2002～2003, including an urban setting, a satellite city and a rural area. The mineralogical composition of these PM₁₀ samples was studied by X-ray diffraction (XRD), environmental scanning electron microscopy / and energy-dispersive X-ray analyzer (ESEM/EDX). The results indicated that mineral composition of PM₁₀ in different seasons and in different region varied significantly. Mineral mass concentration in Beijing PM₁₀ reached the highest percentage in the spring and fell to the lowest level in the autumn. The minerals in the spring PM₁₀ were dominated by clay minerals and quartz, followed by plagioclase, K-feldspar, calcite, dolomite, hematite, pyrite, magnesite, gypsum and laumontite as well as some unidentified materials. Fewer mineral types were collected in summer, however some new components, including K(NH₄)Ca(SO4)₂·H₂O, NH₄Cl and As₂O₃·SO₃ were noted to be present, suggesting that atmospheric chemical reaction in Beijing air were more active in summer than in other seasons. Mineral components in Beijing urban air were at a higher percentage with fewer phases than that in satellite city air. In conclusion, there was considerable variation in mineral components in PM₁₀ samples collected in different seasons and areas, which reflects the related air quality of sampling areas.     

转基因棉花早代材料细胞学变异研究

农杆菌介导转基因棉花早代 ( T0 )材料 ,花粉母细胞的染色体构型变异很大 ,只有部分二价体 ( 7～ 1 6个 ) ,多数是单价体 ,没有更高的价体。二价体位于赤道面 ,但多形成染色体桥。单价体多散布在两极。减数分裂后形成 1～ 8个分体的多分体 ,其中四分体虽然比例很高 ,多为畸形。染色体数目的减少、PMC染色体构型变异等 ,是这类材料高度败育的直接原因     

Production of Primary Triticale from Calluses of Immature Abnormal Hybrid Embryos between Triticum durum and Secale cereale

Plant regeneration was attempted in callus induced from the immature abnormal hybrid embryos between T. durum and S. cereale, using 4-Huorophenoxyacetic acid as a growth regulator. In particular, the relationship of numerical variation in chromosomes between the callus tissues and the regenerated plants was investigated. Cytological observation revealed that there was no distinctive numerical difference between the shoot-forming (SF) and the non-shoot-forming calluses and also between the SF calluses and the regenerated plants. The root-tips of regenerated plants consisted of cells having various chromosome numbers, including the expected 2 n = 3 ×= 21 (genomes, ABR) of which the frequency was 69.8 %. The regenerated plants showed partial fertility, notwithstanding that the hybrid plants were expected to be sterile. Since the frequency of abnormal embryos was about 90 % in this cross, the utilization of abnormal embryos was demonstrated by use of callus culture.