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Urban Park Soil and Vegetation: Effects of Natural and Anthropogenic factors

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Pedosphere 2015年第3期25卷 392-404页

作者： pariente SARAH Helena Michaela ZHEVELEV Atar OZ Laboratory of Geomorphology and Soil Department of Geography and EnvironmentBar-Ilan University

Various soil surface components, such as trees, shrubs and biological crusts, and human recreational activities, e.g., barbecues and trampling by visitors, may divide the area of the urban park into smaller fragments/mieroenvironments, differentiated by their microenvironmental conditions, which may differ in soil and vegetation characteristics. The spatial changes in the soil and vegetation characteristics and their causes were investigated in an urban park located south of Tel Aviv-Jaffa, Israel. The area of the park is 0.5 km^2, including groves, a lake, lawns, and rest areas. Soil was sampled in nine microenvironments, of which seven were within the park： under Ceratonia siliqua trees （CsU）, under ficus sycomorus trees （fLU）, rest area between tables under f. sycomorus （fIB）, rest area under tables under f. sycomorus （fIT）, open area with bare soil （OaS）, open area with biological crust cover （OaC）, and open area covered by herbaceous vegetation （OaV）. Two more microenvironments, planar and sloping open areas （CoP and CoS, respectively） in the vicinity of the park, were used as the controls. Electrical conductivity, concentrations of soluble ions （Mg^2＋, Ca^2＋, Na^＋, K^＋ and HCO3）, pH, contents of organic carbon, calcium carbonate and moisture, and grain size distribution were determined. In addition, herbaceous vegetation cover, number and diversity of herbaceous vegetation species were measured. It was found that soil properties and herbaceous vegetation characteristics varied within the park. Soil organic carbon, electrical conductivity, soluble salts, penetration depth, and vegetation characteristics were affected by human activities, mainly in the rest area between the tables. In contrast, the above characteristics were affected by natural factors mainly in the rest of the microenvironments, which were subjected to low levels of anthropogenic intervention. The heterogeneous structure of the park, as represented by the various microenvironments, offered new

关键词： anthropogenic activity herbaceous vegetation microenvironment soil properties species diversity

Effects of melatonin on the oxidative damage and pancreatic antioxidant defenses in ceruleininduced acute pancreatitis in rats

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Hepatobiliary & Pancreatic Diseases International 2014年第4期13卷 442-446页

作者： Cristina Carrasco Ana Beatriz Rodríguez José A pariente Department of Physiology Neuroimmunophysiology and Chrononutrition Research Group University of Extremadura

BACKGROUND： Oxidative stress is recognized as a pivotal effector of several pathogenic processes, including acute pancreatitis. Reactive oxygen species not just cause damage on the main cellular components, but also influence the expression of antioxidant system genes. Antioxidant molecules, such as melatonin, could be good candidates for the treatment of this multidimensional disease. The present study was to evaluate the chemopreventive effect of melatonin in a rat model of ceruleininduced acute ***： four subcutaneous injections of cerulein（20 μg/kg body weight） were given to Wistar rats at two hours intervals;melatonin was injected intraperitoneally（25 mg/kg body weight）30 minutes before each injection of cerulein. Lipid peroxidation,protein oxidation（carbonyl groups）, total antioxidant status,and glutathione peroxidase activity were determined in pancreatic tissue using commercial ***： The chemopreventive administration of melatonin caused a reduction in lipid peroxidation and protein oxidation due to injections of cerulein. Additionally, melatonin treatment was also able to revert glutathione peroxidase activity and total antioxidant status near to control levels, suggesting that melatonin could prevent from oxidative phenomena in the pancreas, such as lipid peroxidation and protein oxidation,and could stimulate, directly or indirectly, the expression of antioxidant ***： Melatonin, a polyvalent antioxidant, protected the pancreatic damage via the decrease of oxidative stress andincrease of the activities of antioxidant enzymes in ceruleininduced acute pancreatitis.

关键词： acute pancreatitis antioxidants cerulein melatonin oxidative stress

Imaging resolution of biocatalytic activity using nanoscale scanning electrochemical microscopy

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Nano Research 2018年第8期11卷 4232-4244页

作者： Jase M .Abad Alvaro Y. Tesio EmUiano Martinez-Perinan felix pariente Encamacion Lorenzo Departamento de Qufmica Analftica y Andlisis Instrumental Universidad Aut6noma de Madrid Cantoblanco 28049 Madrid Spain Centro de Investigaci6n y Desarrollo en Materiales Avanzados y Almacenamiento de Energfa de Jujuy-CIDMEJu (CONICET-UniversidadNacional de Jujuy) Centro de Desarrollo Tecnol6gico General Savio Av. Martijena s/n 4612-Palpald Jujuy Argentina Instituto Madrileno de Estudios Avanzados en Nanociencia (IMDEA-Nanociencia) Campus UAM Cantoblanco 28049 Madrid Spain

Scanning electrochemical microscopy represents a powerful tool for electro（chemical） characterization of surfaces, but its applicability has been limited in most cases at microscale spatial resolution, and the greatest challenge has been the scaling down to the nanoscale for fabrication and the use of nanometer-sized tips. Here, Pt nanoelectrodes with nanometer electroactive area were fabricated and employed for imaging a distribution of gold nanoparticles （AuNPs） and bioelectrocatalytic activity of a redox-active enzyme immobilized on gold surfaces.

关键词： scanning electrochemicalmicroscopy gold nanoparticle redox enzyme nanoelectrode lactate oxidase

Electrochemically driven phenothiazine modification of carbon nanodots

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Nano Research 2018年第12期11卷 6405-6416页

作者： Monica Mediavilla Emiliano Martinez-Perinan Iria Bravo Tania Garcia-Mendiola Monica Revenga-Parra felix pariente Encarnacion Lorenzo Departamento de Qufmica Analftica yAndlisis Instrumental UniversidadAutonoma de MadridMadrid28049Spain Instituto Madrileno de Estudios Avanzados (IMDEA)Nanociencia Faraday9Campus UAMCantoblancoMadrid28049Spain Institute for Advanced Research in Chemical Sciences (IAdChem) UniversidadAutonoma de MadridMadrid 28049Spain

Carbon nanodots (CNDs) with enriched periphery carboxylic groups were synthesized using the low-cost starting material glucose. The obtained CNDs were assembled onto Au electrodes following one of two strategies: covalent bonding, using cystamine as a cross-linker, or by drop-casting. The immobilized CNDs were covalently modified with the phenothiazine Azure A via electron transfer chemistry; in particular via reactions with aryl diazonium salts. The reaction mechanism for the diazonium functionalization of CNDs was investigated. Spectroelectrochemistry experiments confirmed that electrografting, rather than adsorption, governs the functionalization of CNDs with Azure A. finally, the application of these CNDs as electrocatalysts for the oxidation of hydrazine was demonstrated.

关键词： carbon nanodots Azure A electrografting phenothiazine

Role of melatonin on diabetes-related metabolic disorders

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World Journal of Diabetes 2011年第6期2卷 82-91页

作者： Javier Espino José A pariente Ana B Rodríguez Department of Physiology Neuroimmunophysiology and Chrononutrition Research Group Faculty of ScienceUniversity of Extremadura

Melatonin is a circulating hormone that is mainly re- leased from the pineal gland. It is best known as a regulator of seasonal and circadian rhythms, its levels being high during the night and low during the day. Interestingly, insulin levels are also adapted to day/night changes through melatonin-dependent synchronization. This regulation may be explained by the inhibiting action of melatonin on insulin release, which is transmitted through both the pertussis-toxin-sensitive membrane receptors MT1 and MT2 and the second messengers 3',5' -cyclic adenosine monophosphate, 3',5'-cyclic guanosine monophosphate and inositol 1,4,5-trisphosphate. Melatonin may influence diabetes and associated metabolic disturbances not only by regulating insulin secretion, but also by providing protection against reactive oxygen species, since pancreatic β-cells are very susceptible to oxidative stress because they possess only low-antioxidative capacity. On the other hand, in several genetic association studies, single nucleotide polymorphysms of the human MT2 receptor have been described as being causally linked to an elevated risk of developing type 2 diabetes. This suggests that these individuals maybe more sensitive to the actions of melatonin, thereby leading to impaired insulin secretion. Therefore, block- ing the melatonin-induced inhibition of insulin secretion may be a novel therapeutic avenue for type 2 diabetes.

关键词： Melatonin Circadian rhythm Diabetes Insulin secretion Pancreatic β-cell Melatonin receptor

The Spatial Variability and Temporal Dynamics of Soil Properties as Affected by Visitors’ Pressure in an Urban Park

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Journal of Environmental Protection 2013年第8期4卷 52-64页

作者： Helena M. Zhevelev pariente Sarah Atar Oz Laboratory of Geomorphology and Soil Department of Geography and Environment Bar-Ilan University Ramat Gan Israel.

Soil properties and their tempo-spatial heterogeneity, affected by visitors’ pressure, season and soil depth, were studied in an urban park in Tel-Aviv. Soil was sampled twice yearly in wet and dry seasons. In each season soil was sampled from areas exposed to differing levels of visitors’ pressure (VP), and designated “no VP (Control)”, “High VP” and “Low VP”. The soil samples were taken from two depths. for each soil sample, moisture, organic matter and soluble-ion contents, pH, and electrical conductivity were determined. It was found that different properties were differently affected by VP, seasonal dynamics and soil depth: organic matter content, penetration depth and sodium concentration were the most sensitive to VP;Soil moisture did not respond to VP, but sharply reflected seasonal changes;Calcium and organic matter contents were significantly affected by the soil depth. The sensitivity of soil properties to VP increased from March to July, and the upper soil layer was more sensitive to seasonal dynamics and VP than the deeper layer. Some soil properties exhibited “spotty” patterns;others a “frontal” one. Organic matter content was completely controlled by VP at both depths and in both seasons, and could be used as an indicator of soil status in recreation areas. Visitors’ activities included trampling and other anthropogenic factors that enhanced the spatial changes and seasonal dynamics of soil properties. Based on these measurements the intensity of soil degradation and dynamics was evaluated and used to describe the soil status in an urban park.

关键词： Urban Park Urban Soil Visitors’ Pressure Soil Spatial Variability Seasonal Dynamics

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一种改型海泡石的表面酸度和催化活度

湖南地质 1985年第S1期 141-142页

作者： A.CORMA J.PEREZ—pariente V.fORNTS A.MIfSUD 陈世益

自从沸石作为催化剂被成功采用以后,在这个地区工作的几个研究组看到了粘土矿物用作催化剂的前景。其实,粘土对催化剂的制备有着良好的性能,即是说,在某种情况下,结晶结构能够很方便地被改型变成一种高表面积、以及对某些热处理和化学... 详细信息

自从沸石作为催化剂被成功采用以后,在这个地区工作的几个研究组看到了粘土矿物用作催化剂的前景。其实,粘土对催化剂的制备有着良好的性能,即是说,在某种情况下,结晶结构能够很方便地被改型变成一种高表面积、以及对某些热处理和化学处理的稳定性。在天然粘土矿物中,海泡石分布十分广泛。这种矿物具有在纤维状结构边缘被接合在一起构成的板条状晶体。根据全长5.3A的纤维,通道测量约为11.5A。在某些

关键词：海泡石天然甲基环已烷蛸螵石粘土矿物链烷基环烷烃酸度

阿片制剂在胆囊切除术后发生疑似奥狄氏括约肌功能障碍中的作用被低估

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世界核心医学期刊文摘（胃肠病学分册） 2006年第6期2卷 26-27页

作者： Druart-Blazy A. pariente A. Berthelemy P. Arotarena R. 王晓君 Unitéd'HGE Centre Hospitalier 64046 Pau Cedex

Aims-Pain recurrence after cholecystectomy is often attributed to sphincter of Oddi dysfunction, whose diagnostic criteria and treatments remain uncertain. We performed a retrospective study to assess the possible precipitating role of opiate ingestion in this setting. Methods-The retrospective study of the files of 147 consecutive patients investigated for post-cholecystectomy syndrome by endoscopic ultrasonography and/or endoscopic retrograde cholangiography yielded 37 cases of suspected biliary-type sphincter of Oddi dysfunction. Results-Thirteen patients (30%) with suspected sphincter of Oddi dysfunction had taken opiate-containing drugs 15 minutes to two hours (median 1 hr) before the onset of pain (“Opiate group“). When compared with the 23 patients having not taken opiates (“Non Opiate Group“), they were significantly younger (47 vs. 60 yrs), had a narrower common bile duct (5.0 vs. 7.7 mm), but had similar biochemical abnormalities and belonged to the same Milwaukee’s classes, mainly class II. None of the patients in the “Opiate group“ were submitted to retrograde cholangiography or endoscopic sphincterotomy vs. 52%and 39%, respectively of the patients of the “Non-Opiate Group“. After a mean follow-up of 3.5 years, there were three recurrences of biliary-type pain (1 choledochal stone, and 2 suspected sphincter of Oddi dysfunction) in the “Opiate Group“, and 2 (1 choledochal stone, 1 after codeine intake) in the “Non-Opiate Group“. Conclusions-Opiate intake is a frequent cause of suspicion of sphincter of Oddi dysfunction after cholecystectomy, especially in young patients with a narrow common bile duct. A careful history taking is essential to avoid unnecessary and potentially harmful procedures.

关键词：胆囊切除术后综合征括约肌功能障碍阿片药物奥狄氏制剂超声内镜检查胆总管结石逆行胆管造影

有先兆子痫病史女性的动脉粥样硬化长期发病率

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中华高血压杂志 2015年第1期23卷 99-99页

作者： Kessous R Shoham-Vardi I pariente G Sergienko R Sheiner E 刘莉叶鹏

该研究旨在确定重度及复发先兆子痫是否增加母亲长期动脉粥样硬化性疾病的发生风险。方法：进行一项以人口为基础的研究，比较1988—2012年分娩的女性队列中长期动脉粥样硬化的发病率。研究变量为先兆子痫。平均随访时间为11．2年。

关键词：动脉粥样硬化性疾病先兆子痫发病率女性病史发生风险随访时间