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Interactive effect of dissolved organic matter and phenanthrene on soil enzymatic activities

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Journal of Environmental Sciences 2010年第4期22卷 607-614页

作者： Xinhua Zhan,Wenzhu Wu,Lixiang Zhou,Jianru Liang,Tinghui Jiang college of Resources and Environmental Sciences,Nanjing Agricultural University,Nanjing 210095,china.Greenstar Plant Products Inc.,9430 198 St,Langley,Bc,canada V1M3c8. college of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 China

The investigation of dissolved organic matter （DOM） on urease, catalase and polyphenol oxidase activity in a phenanthrene （phe）- contaminated soil was conducted under laboratory incubation conditions. Values of soil enzymatic activity depended mainly on incubation time. In the initial 16 days, urease activity increased, and was followed by a decrease. In the initial 8 days, catalase activity decreased and then increased. Variation of polyphenol oxidase activity was just the reverse of catalase activity. After 30 days of incubation, no pronounced difference among treatments with phe, phe and DOM, and control were detected in urease, catalase and polyphenol oxidase activity. phe might inhibit urease and catalase, and stimulate polyphenol oxidase. DOM could improve inhibition of phe in soil urease and catalase activity during the initial period of applying DOM. Nevertheless, DOM had no significant effect on polyphenol oxidase activity in the phe contaminated soil. There was a negative correlation between catalase and polyphenol oxidase （r = -0.761＊＊＊）, and catalase and urease （r = -0.554＊＊）. Additionally, a positive correlation between polyphenol oxidase and urease was also detected （r = 0.701＊＊＊）. It is implied that the formed DOM after application of organic wastes into soils may counteract the inhibition of polycyclic aromatic hydrocarbons in soil enzyme activities.

关键词： polycyclic aromatic hydrocarbons dissolved organic matter phenanthrene soil enzymes

[Nle^4-D-phe^7]-α-促黑素激素显著增加白人志愿者毛发、皮肤色素的生成及紫外线损伤的减少

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世界核心医学期刊文摘（皮肤病学分册） 2006年第11期2卷 29-30页

作者： Barnetson R.S.c. Ooi T.K.T. 李翠华 Department of Dermatology Royal Prince Alfred Hospital Camperdown NSW 2050 AustraliaProf.

Epidermal melanin reduces some effects of UV radiation,the major cause of skin cancer. To examine whether induced melanin can provide protection from sunburn injury,65 subjects completed a trial with the potent synthetic melanotropin, [Nle4-D-phe7]-α-melanocyte-stimulating hormone ([Nle4-D-phe7]-α-MSH) delivered by subcutaneous injection into the abdomen at 0.16 mg/kg for three 10-day cycles over 3 months. Melanin density, measured by reflectance spectroscopy, increased significantly in all [Nle4-D-phe7]-α-MSH-treated subjects. The highest increases were in volunteers with lowest baseline skin melanin levels. In subjects with low minimal erythemal dose (MED) skin type,melanin increased by an average of 41%(from 2.55 to 3.59, Pcebo)-over eight separate skin sites compared with only 12%(from 4.18 to 4.70,Pcebo) in subjects with a high-MED skin type. Epidermal sunburn cells resulting from exposure to 3 MED of UV radiation were reduced by more than 50%after [Nle4-D-phe7]-α-MSH treatment in the volunteers with low baseline MED. Thymine dimer formation was also shown to be reduced by 59%(P=0.002) in the epidermal basal layer. This study has shown for the first time the potential ability of a synthetic hormone that augments melanin production to provide photoprotection to people who normally burn in direct sunlight.

关键词：促黑素激素 Nle^4-D-phe^7 紫外线损伤皮肤色素最小红斑量皮肤类型表皮基底层黑素

Soil Biological and Biochemical Responses to cd Exposure

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Open Journal of Soil Science 2011年第1期1卷 8-15页

作者： R. Ebhin Masto Rajkumar Ahirwar Joshy George L. c. Ram V. A. Selvi 不详

Heavy metals can stimulate the activity of soil enzymes in smaller amounts, but act as inhibitors if present in high concentrations. Natural and anthropogenic heavy metal contamination and its disturbances on soils can be evaluated by using enzymatic activities as sensors. To study the effects of cd, soil added with known cd concentrations (0, 10, 20, 50,100 and 200 mg/kg soil) were incubated for a period of 30 days at 28℃. At intervals of 0, 5, 10, 20 and 30 days samples were withdrawn for enzyme assays like dehydrogenase (DHA), catalase (cAT), phenol oxidase (phe), and peroxidise (PER). In a separate experiment the effect of cd on active microbial biomass carbon (AMBc), basal soil respiration (BSR), and metabolic quotient were studied. AMBc showed a reduction trend with increase in cd concentration, and a maximum reduction of 47% was observed at 30th day for 200 mg/kg treatment. BSR also has got the same trend, with a maximum decrease of 42% at the 30th day. With the rate of cd amendments and treatment period, DHA has shown an inhibition trend;whereas maximum decrease was observed for 200 mg/kg treatment at 30th day. cAT, PER, and phe were found to be increased with cd addition and remained at higher levels than in the control soil. These changes can be attributed to the effect of cd on microbial activities. Based on cluster analysis, AMBc appears to be the sensitive indicators for the soil exposed to cd contamination.

关键词： chemical Elements Dynamics Synergism Antagonism Information Function Hierarchic Order Soil Formation Mineral Substratum

Searching systematics for nonfactorizable contributions to B^(-)and B^(0) hadronic decays

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chinese Physics c 2022年第7期46卷 47-55页

作者： Maninder Kaur Supreet Pal Singh R.c.Verma Department of Physics Punjabi UniversityPatiala-147002India

The two-body weak decays B→πD/B→ρD and B→πD are examined using isospin analysis to study nonfactorizable *** determining strong interaction phases and obtaining factorizable contributions from spectator-quark diagrams for Nc=3,we determine nonfactorizable isospin amplitudes from the experimental data for these *** results support the universality of the ratio of nonfactorizable isospin reduced amplitudes for these decays within experimental *** demonstrate that these systematics are not coincidental,we also plot our results *** ratio.

关键词： nonfactorization weak hadronic decays HEP-phe

Transcriptome Profiling and Biochemical Studies Reveal New Mechanisms for cotton Fiber cell Elongation

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分子植物育种 2007年第2期5卷 159-160页

作者： Y.H. Shi Y.M. Qin c.Y. Hu Y. Pang Y.X. Zhu The National laboratory of Protein Engineering and Plant Genetic Engineering College of Life Sciences Peking University Beijing 100871 China

cotton is the world's most important natural textile fi ber, and is practiced on about 2.5% of arable land that supported the life of about 100 million family units. Each cotton fi ber, about 25 000 per seed, is a sin... 详细信息

关键词：生物化学棉花纤维伸长率

耐化学腐蚀和疏水性的食品包装用含SnO_(2)生物纳米复合材料

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Transactions of Nonferrous Metals Society of china 2023年第7期33卷 2136-2154页

作者： Joseph Raj XAVIER cDHANALAKSHMI Shanmuga Sundari cHANDRARAJ SPVINODHINI Department of chemistry Saveetha School of EngineeringSaveetha Institute of Medical and Technical SciencesChennai-602105Tamil NaduIndia Department of chemistry Vel Tech Rangarajan Dr.Sagunthala R&D Institute of Science and TechnologyChennai-600062Tamil NaduIndia

研究了聚(天冬酰胺-共苯丙氨酸)(P(Asn-co-phe)/SnO_(2))对环氧树脂(EP)涂层防护性能的影响。电化学阻抗谱分析表明,与纯环氧树脂涂层相比,马口铁表面EP-P(Asn-co-phe)/SnO_(2)纳米复合材料涂层具有更好的防护作用。EP-P(Asn-co-phe)/Sn... 详细信息

研究了聚(天冬酰胺-共苯丙氨酸)(P(Asn-co-phe)/SnO_(2))对环氧树脂(EP)涂层防护性能的影响。电化学阻抗谱分析表明,与纯环氧树脂涂层相比,马口铁表面EP-P(Asn-co-phe)/SnO_(2)纳米复合材料涂层具有更好的防护作用。EP-P(Asn-co-phe)/SnO_(2)纳米复合材料涂层的电阻(Rcoat)为3854.70 kΩ·cm^(2),比环氧树脂涂层的大38倍。扫描电化学显微镜分析表明,EP-P(Asn-co-phe)/SnO_(2)的电流分布更小。通过XRD和SEM/EDX对降解产物进行分析,证实了功能化SnO_(2)颗粒对环氧树脂涂层防护能力的影响。EP-P(Asn-co-phe)/SnO_(2)纳米复合材料涂层的水接触角为133°,证实了其疏水性。此外,与纯环氧树脂涂层相比,EP-P(Asn-co-phe)/SnO_(2)纳米材料复合涂层具有更高的力学性能和抗菌活性。综上,由于在环氧树脂基体中添加了P(Asn-co-phe)/SnO_(2)纳米颗粒,EP-P(Asn-co-phe)/SnO_(2)纳米复合材料提供了出色的屏障和力学性能,从而阻碍了材料的降解,有助于延长涂层钢的寿命。

关键词：马口铁环氧树脂 SnO_(2) 纳米材料复合涂层共聚物热稳定性硬度

两个巴西种族及反复性流产患者Tyr204phe和Val34Leu基因的多态性

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世界核心医学期刊文摘（妇产科学分册） 2005年第4期1卷 50-50页

作者： Barbosa H.c.L. carvalho E.c.c. BariniR. 朱国栋

This study investigated the prevalence of Tyr204phe and Val34Leu polymorphisms in two Brazilian ethnic groups (171 caucasians and 27 Blacks, and 117 men and 81 women) and in patients with recurrent miscarriages (RM) (86 women: 53 caucasians and 33 Blacks). Study groups were matched to control groups by race and age. The prevalence of these polymorphisms did not differ between patients with RM and controls or between caucasian and blacks, suggesting that these polymorphisms cannot be considered a risk factor for RM.

关键词： Tyr204phe Val34Leu 多态性高加索人流产者间人

HIV感染儿童接受强化的抗逆转录病毒治疗(HAART)后的HIV脑病发病率及流行

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世界核心医学期刊文摘（儿科学分册） 2005年第8期1卷 29-30页

作者： chiriboga c.A. Fleishman S. champion S. 虎小毅 columbia University Medical center Harkness Pavillion 552 180 Fort Washington Avenue New York NY 10032 United States Dr.

Objective: To describe neurologic outcomes in children infected with HIV in t he era of highly active anti- retroviral therapy (HAART), including rates of pr ogressive HIV encephalopathy (phe) and clinical sequelae among phe survivors. St udy design: Neurobehavior and school placement was assessed prospectively in the year 2000 in 126 children infected with HIV. phe, developmental delay, and atte ntion deficit disorder (ADHD) were the main outcome variables analyzed. Predicto rs of phe were assessed in controlled analysis among age- matched controls. Res ults: The rate of active phe in 2000 was 1.6% (n = 2), and the prevalence of a rrested phe was 10% (n = 13). Residual motor and cognitive sequelae and need f or special education was found in the majority of survivors. phe relapse occurre d in 3 (23% ) children with previously arrested phe. Viral load (VL) was the on ly significant factor associated with *** or phe was not associated with ADH D. Isolated developmental delay was not associated with HIV. conclusions: phe is an infrequent and reversible complication of HIV infection that responds to HAA RT and that may relapse if control of the virus is lost. children with arrested phe show higher rates of residual neurologic, cognitive, and scholastic impairme nts compared with children who never had phe. children with arrested phe are the group of children with HIV infectionmost at risk for phe, in the form of a rela pse.

关键词： HIV脑病 HIV感染 HAART 神经行为存活患者病毒载量发育性活动率静止期存活者

中位神经运动传导速度与髓磷脂蛋白零基因突变相一致

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世界核心医学期刊文摘（神经病学分册） 2005年第8期1卷 40-41页

作者： Lee Y.-c. Soong B.-W. 赵睿

Background: Myelin protein zero gene (MPZ) mutations may account for a small p roportion of cases of charcot-Marie-Tooth disease (cMT). Different MPZ mutatio ns may be associated with different clinical and electrophysiological phenotypes .Objectives: To expand our understanding of the characteristics of nerve conduct ion velocity (NcV) in patients with different MPZ mutations, the authors collect ed and analysed the NcVvalues from patients with MPZ mutations. Materials and Me thods:The NcVs of fourteen patients from six families carrying MPZ mutations of Val58Asp, Ser63phe, Thr65Ile,Arg98cys,Arg98His, and Ser233fs were collected retr ospectively. Five of them had received nerve conduction studies (NcS) twice. The mutations were verified by polymerase chain reaction (PcR)-amplifications and nucleotide sequencing. Scatterplot analyses of media n motor NcV (MNcV) versus specific MPZ mutation were performed. Results: The med ian MNcV varied widely,with a mean of 16.3 m/s (SD=7.7 m/s) and a range of 5.1- 32.9 m/s. Median MNcVs of patients with particular MPZ mutations were similar. M oreover, Median MNcV did not change significantly over time. conclusions: There was concordance between median MNcV and specific MPZ ***, median M NcV is not an ideal measure with which to distinguish cMT1B patients with MPZ mu tations from cMT1A patients with PMP22 mutations.

关键词：运动传导速度基因突变髓磷脂核苷酸序列肌肉萎缩电生理学散点图时间变化