Excess trace metal effects on cotton: 4. Chromium and lithium in Yolo loam soil

Abstract

Two cultivars of cotton (Gossypium spp) were grown in Yolo loam soil in a glasshouse to determine phytotoxicity effects of Cr and Li and possible interactions with other metals. The Cr at 100 μg/g soil had no adverse effects on either cultivar studied. A Cr increase was not observed in either stems or leaves. Both cultivars tolerated 25 and 50 μg Li/g soil. The 50 μg Li/g soil resulted in leaves of Acala SJ‐2 with 432 μg Li/g leaves and 720 in Giza 45. The 100 μg Li/g soil resulted in 74% and 87% leaf yield reductions in Acala SJ‐2 and Giza 45 respectively. Leaf concentrations of Li respectively were 1950 and 1850 μg/g. Except at the highest level of Li, leaves had higher concentrations of Li than did roots. The Cr and Li resulted in some plant metal interactions.     

Effects of pirenzepine on expression of MMP-2 and TIMP-2 in stroma of sclera in chick myopic eyes

AIM:To observe the effect of intravitreal injection of pirenzepine on form-deprivation myopia in chicks. METHODS:Forty-one day old chicks were randomly divided into 4 groups:normal control group, form deprivation group, vehicle control group and pirenzepine injection group. The right eyes of all chicks were used as experimental eyes. The deprived eyes in vehicle control group and pirenzepine injection group received daily intravitreal injection of vehicle control solution(0.01 mol/L PBS) and pirenzepine(1%in PBS), respectively. Optical examinations such as refraction, axial length and equatorial diameter were made at the end of the 5th day. The mRNA and protein levels of matrix metalloproteinase 2(MMP-2) and tissue inhibitor of metalloproteinase-2(TIMP-2), and the activity of MMP-2 were detected by RT-PCR, Western blotting and zymography analysis,respectively. RESULTS:Refraction, axial length and equatorial diameter of the eyes in pirenzepine injection group were significantly lower than those in form deprivation group and vehicle control group(P<0.05), but those were higher(P<0.05) and the eyes were relatively myopic as compared with normal control group. The mRNA expression, protein le vels and activity of MMP-2 in pirenzepine group were significantly higher than those in normal control group(P<0.01), and were significantly lower than those in form deprivation group and vehicle control group(P<0.01, P<0.01). The mRNA and protein levels of TIMP-2 in pirenzepine group were significantly lower than those in normal control group(P<0.01), and was significantly higher than those in form deprivation group and vehicle control group(P<0.01, P<0.01). CONCLUSION:Intravitreal injection of pirenzepine may partly prevent form-deprivation myopia by modulating the expression of MMP-2 and TIMP-2 in the fibrous layer of sclera.     

Interaction of NR2D subunit of NMDA receptor with MOCA

AIM: To identify the potential proteins interacting with NR2D subunit of NMDA receptor by yeast two-hybrid screening and to investigate the role of NR2D in excitotoxicity of the retina.METHODS: The Clontech GAL4 yeast two-hybrid system was used to screen the mouse brain cDNA library, and the bait plasmid containing C-terminus of NR2D was constructed. Physical interaction between 2 proteins was verified by co-immunoprecipitation assay. The subcellular localization of 2 proteins in the mouse retina was observed under microscope with immunofluorescence.RESULTS: Modifier of cell adhesion (MOCA) was identified as a new protein interacting with NR2D. MOCA and NR2D were co-expressed in the mouse retina. CONCLUSION: MOCA specifically interacts with NR2D, which provides the experimental basis for identifying the role of glutamate excitotoxicity in the retina neurodegeneration.     

茄子新品种青茄2号的选育

青茄2号是以H2005-8-4-3为母本,以X2005-1-7-9为父本选育的茄子一代杂种。中晚熟,始花节位为第7~8节,生育期171d(天)左右;果实卵圆形,纵径17.6cm,横径11.3cm,果皮绿色,果面光滑,单果质量为0.49kg,平均每667m2产量可达5000kg。田间对黄萎病、青枯病、绵疫病和病毒病的抗性与对照新乡糙青茄相当。适于河南省平顶山、漯河、郑州、驻马店、信阳以及各地喜好绿茄地区栽培。     

Soil nitrogen and denitrification potential as affected by land use and stand age following agricultural abandonment in a headwater catchment

Changes in vegetation and soil properties because of agricultural abandonment may affect soil nitrogen (N) and associated processes. We investigated soil N (total N: TN, inorganic N: NH₄–N and NO₃–N) and denitrification potential in cropland, pine plantations and abandoned agricultural land along a secondary succession sequence (grassland→shrubland→secondary forest) in a headwater catchment in the Qinling Mountains, northwest China. The results show that the soil denitrification potential differed significantly among the five land‐use types with the highest potential in the secondary forest, followed by grassland, shrubland, cropland and plantations. The denitrification potential of the 20‐ to 40‐cm layer was significantly lower compared with the topsoil (0–20 cm) across all land‐use types. TN, soil organic matter (SOM) and NH₄–N increased significantly with stand age, whereas there was an opposite trend in soil pH. However, the denitrification potential did not relate to stand age in a linear manner. We conclude that changes in soil TN, SOM and pH during vegetation succession following agricultural abandonment are critical controls on the denitrification potential.     

人呼吸道合胞病毒的研究与防治进展

人呼吸道合胞病毒是全世界婴幼儿下呼吸道感染最常见的病原体,导致每年超过300万人住院和20万以上的人死亡,给全球带来了非常严重的经济和社会负担。目前,尚不存在防治RSV的疫苗,也没有特异性强、安全性高的抗RSV药物。对HRSV的结构、流行病学特征以及疾病模型构建方面的研究进展进行综述,并对已有的检测和治疗方法进行总结,旨在为今后开发抗HRSV的药物提供全面的参考信息。     

Correlation of Soil pH and Mehlich‐3 Phosphorus with Postflood Rice Phosphorus Concentrations in Arkansas

Abstract

Plant‐available phosphorus (P) measured by routine soil‐test methods is poorly correlated with rice grain yield in Arkansas. Our objective was to determine whether soil water pH (pH_w) and Mehlich‐3 P were correlated with growth and yield of rice grown on silt loam soils. Data from 35 field studies were used to correlate Mehlich‐3 P and pH_w with relative yield, dry matter accumulation, and P concentration at the midtillering stage. Significant linear or nonlinear relationships between pH_w or Mehlich‐3 P with rice growth parameters were delineated but explained less than 27% of the variability in dry matter and P concentrations at the midtillering stage and grain yield at maturity. Mehlich‐3 P and pH_w together explained 61% of the variability in midtillering P concentrations. Midtillering whole‐plant P concentrations were positively related to relative grain yield and dry matter production and will be used to identify soils with limited P availability for rice in Arkansas.     

Nitrogen requirements associated with improved conservation tillage for corn production

Abstract

Excessive soil erosion and use of nitrogen fertilizer are costly to the Atlantic Coastal Plain corn (zea mays L., ’Funks G 4507') producer and both may serve to create environmental hazards. An in‐row chisel (36 cm deep) tillage method was compared with the standard 5 cm fluted coulter method for planting corn in premature wheat (Triticim aestivum L.) residues grown on an Orangeburg sandy loam (Typic Paleudult). Five orthogonal N levels ranging up to 440 kg of N/ha were used to determine an economic N optimum for each tillage method.

The in‐row chisel tillage method provides a possible yield advantage in the Atlantic Coastal Plain because of observed restricting soil layers within the normal corn rooting zone. The estimated profit‐maximizing quantities of N fertilizer were 262 and 295 kg of N/ha (234 and 263 1b of N/acre) for the fluted coulter and in‐row tillage procedures, respectively. Corn grain yields associated with these inputs were 9.6 × 10³ and 12.6 × 10³ kg/ha (153 and 200 bu/acre), respectively. The yield increase associated with in‐row chiseling through a 2.5 metric ton mulched surface is attributed to potentially improved rooting and more efficient water storage and use.     

产单核细胞李斯特菌P60蛋白的可溶性表达

以食品中分离到的L.mXFL0605株为试验菌株,PCR扩增得到iap全基因。将iap连接到pET-28a(+)载体进行原核表达,分别采用培养温度为25℃或37℃,IPTG浓度为5μg/mL或10μg/mL优化组合进行诱导。结果显示,当采用37℃培养和10μg/mLIPTG诱导时可以获得部分可溶性表达的p60,重组p60蛋白分子质量约60 ku。     

基于开源J2EE框架的高校实验教学管理系统研究

依据高等院校实验教学管理的应用需求,在分析开源框架体系结构的基础上,通过整合Struts、Spring和Hibernate,利用分层解耦、框架管理层次的思想构建了一个基于开源J2EE的应用架构,并据此架构开发了高校实验教学管理系统。系统可靠性高,安全性好,可扩展性和可维护性强,能有效提高高校实验教学管理和服务效率。