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Telomeres:Linking stress and survival,ecology and evolution

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Current Zoology 2010年第6期56卷 714-727页

作者： Mark F.HAUSSMANN Nicole M.marchetto Department of Biology Bucknell University

Telomeres are protective structures at the ends of eukaryotic chromosomes. The loss of telomeres through cell divisionand oxidative stress is related to cellular aging, organismal growth and disease. In this way, telomeres link molecular andcellular mechanisms with organismal processes, and may explain variation in a number of important life-history traits. Here, wediscuss how telomere biology relates to the study of physiological ecology and life history evolution. We emphasize currentknowledge on how telomeres may relate to growth, survival and lifespan in natural populations. We finish by examining interestingnew connections between telomeres and the glucocorticoid stress response. Glucocorticoids are often employed as indices ofphysiological condition, and there is evidence that the glucocorticoid stress response is adaptive. We suggest that one way thatglucocorticoids impact organismal survival is through elevated oxidative stress and telomere loss. Future work needs to establishand explore the link between the glucocorticoid stress response and telomere shortening in natural populations. If a link is found,it provides an explanatory mechanism by which environmental perturbation impacts life history

关键词：端粒生物学生理生态生存压力链接进化糖皮质激素应激反应应力损失

Interference of iron as a coagulant on MIB removal by powdered activated carbon adsorption for low turbidity waters

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Journal of Environmental Sciences 2013年第8期25卷 1575-1582页

作者： Ferreira Filho SIDNEY SECKLER marchetto MARGARIDA Alves Laganaro ROSEMEIRE Department of Hydraulic and Environmental Engineering Polytechnic School University of Sao Paulo Department of Sanitary and Environmental Engineering University of Mato Grosso Companhia de Saneamento Basico do Estado de So Paulo(SABESP)

Powered activated carbon （PAC） is widely used in water treatment plants to minimize odors in drinking water. This study investigated the removal of 2-methylisoborneol （MIB） by PAC adsorption, combined with coagulation using iron as a coagulant. The adsorption and coagulation process were studied through different case scenarios of jar tests. The analysis evaluated the effect of PAC dosing in the liquid phase immediately before or after the coagulant addition. Ferric sulphate was used as the coagulant with dosages from 10 to 30 mg/L, and PAC dosages varied from 10 to 40 mg/L. The highest MIB removal efficiency （about 70%） was achieved without the coagulant addition and with the highest PAC dosage （40 mg/L）. Lower MIB removal efficiencies were observed in the presence of coagulant, showing a clear interference of the iron precipitate or coagulant in the adsorption process. The degree of interference of the coagulation process in the MIB removal was proportional to the ratio of ferric hydroxide mass to the PAC mass. For both cases of PAC dosing, upstream and downstream of the coagulant injection point, the MIB removal efficiency was similar. However, MIB removal efficiency was 15% lower when compared with experiments without the coagulant application. This interference in the MIB adsorption occurs potentially because the coagulant coats the surface of the carbon and interferes with the MIB coming in contact with the carbon＇s surface and pores. This constraint requires an increase of the PAC dosage to provide the same efficiency observed without coagulation.

关键词： adsorption 2-methylisoborneol (MIB) coagulation activated carbon

Microscale study of frictional properties of graphene in ultra high vacuum

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Friction 2015年第2期3卷 161-169页

作者： Diego marchetto Tim FESER Martin DIENWIEBEL Fraunhofer-Institute for Mechanics of Materials Microtribology CenterμTCWöhlerstr.1179108 FreiburgGermany Karlsruhe Institute of Technology Institute for Applied Materials-Computational Materials Science IAM-CMSKaiserstr.1276131 KarlsruheGermany

We report on the frictional properties of epitaxial graphene on SiC in ultra high *** have been performed using a microtribometer in the load regime of 0.5 to 1 *** observed that a ruby sphere sliding against graphene results in very low friction coefficients ranging from 0.02 to *** friction and also the stability of the graphene layer is higher than that under similar conditions in ambient *** friction shows a load *** it was found that graphene masks the frictional anisotropy which was observed on the SiC surface.

关键词： graphene SiC friction vacuum microtribology anisotropy

意大利的大气湿沉降化学:一项五年研究的成果

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人类环境杂志 1996年第1期25卷 21-25页

作者： Rosario Mosello Aldo marchetto 李哲 CNR Istituto Italiano di Idrobiologia I-28048 PallanzaItaly

1988～1992年间,意大利环境部主办了一项湿沉降协作研究,参加的有44个研究所,47个实验室和172个采样站。质量控制分析包括根据离子平衡及计算出的传导率对结果进行年度间相互核准及验证。意大利北部的采样站主要设在城市和工业区,而南... 详细信息

1988～1992年间,意大利环境部主办了一项湿沉降协作研究,参加的有44个研究所,47个实验室和172个采样站。质量控制分析包括根据离子平衡及计算出的传导率对结果进行年度间相互核准及验证。意大利北部的采样站主要设在城市和工业区,而南部和岛屿上的采样站大多设在农村。聚类分析突出显示出8个化学类别,它们相应于不同的地理位置。由于撒哈拉沙漠尘埃偶发性传输的影响,造成了湿沉降化学具有大量碱性阳离子沉降的特征。在西北部,酸度较高,而且硫酸盐、硝酸盐及铵的浓度也较高,而在北方的其它地区,铵和钙缓和了酸性。在南部(尤其是阿尔卑斯山区站),硫酸盐和铵的浓度均较低(硝酸盐除外),但是全都高于偏远地区的测量值。

关键词：意大利大气湿沉降化学试验

Long-term alpha interferon and lamivudine combination therapy in non-responder patients with anti-HBe-positive chronic hepatitis B:Results of an open,controlled trial

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World Journal of Gastroenterology 2003年第7期9卷 1491-1495页

作者： M. Francesca Jaboli Carlo Fabbri Stefania Liva Francesco Azzaroli Giovanni Nigro Silvia Giovanelli Francesco Ferrara Anna Miracolo Sabrina.marchetto Marco Montagnani Antonio Colecchia Davide Festi Letizia Bacchi Reggiani Enrico Roda Giuseppe Mazzella Department of Internal Medicine and Gastroenterology University of BolognaItaly Department of Gastroenterology and Gastrointestinal Endoscopy Bellaria HospitalBolognaItaly Department of Medicine and Aging University of ChietiItaly Department of Cardiology University of BolognaItaly

AIM: To investigate the safety and efficacy of long-term combination therapy with alpha interferon and lamivudine in non-responsive patients with anti-HBe-positive chronic hepatitis ***: 34 patients received combination treatment (1 month lamivudine, 12 month lamivudine+interferon, 6month lamivudine), 24 received lamivudine (12 months),24 received interferon (12 months). Interferon was administered at 6 MU tiw and lamivudine at 100 mg orally once daily. Patients were followed up for 6 months after ***: At the end of treatment, HBV DNA negativity rates were 88 % with lamivudine+interferon, 99 % with lamivudine and 55 % with interferon, (P=0.004, combination therapy vs. interferon, and P=0.001 lamivudine ***), and serum transaminase normalization rates were 84 %, 91% and 53 % (P=0.01 combination therapy vs. interferon, and P=0.012 lamivudine vs. interferon). Six months later, HBV DNA negativity rates were 44 % with lamivudine+interferon, 33 % with lamivudine and 25 % with interferon, and serum transaminase normalization rates were 61%, 42 % and 45 %, respectively, without statistical significance. No YMDD variants were observed with lamivudine+interferon (vs. 12 % with lamivudine). The combination therapy appeared to be safe. CONCLUSION: Although viral clearance and transaminase normalization are slower with long-term lamivudine+interferon than that with lamivudine alone, the combination regimen seems to provide more lasting benefits and to protect against the appearance of YMDD variants. Studies with other regimens regarding sequence and duration are needed.

关键词：干扰素拉米夫定联合用药慢性乙型肝炎