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Asian Pacific Journal of Tropical Medicine 2017年第1期10卷 42-46页

作者： Salmon A Adebayo Leshweni J Shai jacobus n eloff Phytomedicine Programme Department of Paraclinical SciencesUniversity of Pretoria Department of Biomedical Sciences Faculty of ScienceTshwane University of Technology

Objective: To investigate the anti-inflammatory activity of different fractions and glutinol(isolated compound),using nitric oxide synthase and cyclooxygenase(COX) inhibition as an indication of anti-inflammatory activity,Methods: Anti-inflammatory activity was evaluated using an in vitro assay determining the inhibition of the activity of pro-inflammatory enzyme model,Cyclooxygenases and inducible nitric oxide synthase are crucial enzymes involved in the pathogenesis of many chronic inflammatory conditions,Results: Sub-fraction F3.3 that was derived from n-hexane fraction of PA leaves significantly inhibited(P = 0.01) the catalytic activity of COX-2(IC50 = 0.67 μg/m L) better than isolated compound,glutinol(IC50 = 1.22 μg/m L),compound 2(CP2)(IC50 = 1.71 μg/m L) and sub-fraction F3.3.0(IC50 = 1.30 μg/m L),A similar trend was observed in investigation of the inhibition of nitric oxide synthesis in RAW 264.7 cells by F3.3,glutinol,CP2 and F3.3.0,Inducible COX-2 and inducible nitric oxide synthase are among potent signalling enzymes that exacerbate inflammation,Conclusions: Bioactive sub-fractions(F3.3 and F3.3.0) derived from the n-hexane fraction of PA had good anti-inflammatory activity,and the isolated compound,and glutinol may be useful as a template for the development of new anti-inflammatory drugs.

关键词： Peltophorum africanum COX-1/COX-2 inOS nitric oxide Anti-inflammatory

Influence of Flow Regime on the Vegetation Zonation along Mountain Streams in the Western Cape, South Africa

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Journal of Mountain Science 2015年第6期12卷 1484-1498页

作者： Erwin jacobus Joannes SIEBEn University of the Free State Qwaqwa Campus Afromontane Research Unit

Zonation patterns of riparian vegetation have been sampled and described in mountain streams in two catchments in the Hottentots-Holland Mountains, Western Cape, South Africa. Six main vegetation types that differ in structure and species composition, are dominant along these river banks: Aquatic vegetation, Wetbanks, Palmiet, Scrub, Forest and Shrubland(Fynbos). The study aims to correlate the vegetation patterns to flooding patterns, in particular the inundation frequency and stream power. A problem arises: because these catchments are ungauged, like most mountain catchments, with the only weirs at the downstream end of the catchment. Discharge data at the weirs are extrapolated to the sites upstream by multiplication with a factor based on the size of the subcatchment that drains through a sample site. In this way, recurrence intervals for floods in mountain streams are derived. Discharges at sites are also calculated using bed roughness(Manning's n) and slope in straight sections with uniform flow conditions. Stream power is derived from the discharges calculated in this manner. The combination of stream power and recurrence intervals explains the occurrence of most vegetation types occurring on the banks, except for one type: Afromontane Forest. This type is probably more dependent on other factors, such as protection from fire and the depth of the groundwater table.

关键词： Hydrology Hydraulics Riparian vegetation Mountain streams Floods Stream power Manning's n.

Relict glacial landscape in the Sierra Baguales Mountain Range(50°-51°S):evidence of glaciation dynamics and types in the eastern foothills of the southern Patagonian Andes

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Journal of Mountain Science 2017年第2期14卷 282-295页

作者： ARAOS.JoséMiguel LE ROUX.jacobus Philiphus GUTIERREZ.néstor Mauricio Department of Geology FCFMUniversidad de ChilePlaza Ercilla#803SantiagoChile Department of Geography Faculty of Social Sciences.Universidad Alberto HurtadoUienfuegos#41SantiagoChile Department of Geology FCFMUniversidad de Chile.Andean Geothermal Centre of ExcellencePlaza Ereilla#803SantiagoChile

The glacial morphology of southern South American presents invaluable evidence to reconstruct former glacier behaviour and its relation to climate and environmental changes. However, there are still spatial and temporal gaps in the reconstruction of the Holocene Patagonian glacial landscape. Here we present the first geomorphological record for the Sierra Baguales Mountain Range(SBMR), forming the eastern foothills of the Southern Patagonian Andes 200 km from the Pacific coast. This area is topographically isolated from the Southern Patagonian Ice Field(SPIF), and is affected by the Westerly Winds. The study area shows evidence of ice sheet and alpine glaciations related to Andean uplift,which caused a marked climatic contrast between its western and eastern flanks since the Last Glacial Maximum(LGM). The regional rock mass strength and precipitation gradient acted as a controlling factor in the glacial cirque distribution and sizes, as well as in the development of glaciation types. We report new radiocarbon dates associated with warm/dry to cold/wet climatic changes during the middle Holocene, when former small alpine glaciers were located in the uppermost section of the SBMR basins, and eventually converged to form a small ice field or a composite valley glacier at lower *** can be explained by an estimated regional temperature drop of 3.8°C±0.8°C, based on a 585±26m Equilibrium Line Altitude(ELA) descent, inferred by geomorphological evidence and the Accumulation Area Ratio(AAR), in addition to a free-air adiabatic lapse rate. Subsequently, the glaciers receded due to climatic factors including a rise in temperature, as well as non-climatic factors, mainly the glacier bedrock topography.

关键词： Glacial morphology Sierra Baguales Ice sheet glaciations Alpine glaciations Middle Holocene

Optoelectronic properties analysis of silicon light-emitting diode monolithically integrated in standard CMOS IC

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Chinese Physics B 2019年第10期28卷 115-120页

作者： Yanxu Chen Dongliang Xu Kaikai Xu ning Zhang Siyang Liu Jianming Zhao Qian Luo State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of ChinaChengdu 610054China national ASIC System Engineering Research Center Southeast UniversityNanjing 210096China Department of Electrical Engineering University of South AfricaPretoria 0001South Africa Faculty of Electrical and Computer Engineering State University of Campinas-UNICAMPCampinas CEP 13083-852Brazil

Si p^+n junction diodes operating in the mode of avalanche breakdown are capable of emitting light in the visible range of 400-900 nm. In this study, to realize the switching speed in the GHz range, we present a transient model to shorten the carrier lifetime in the high electric field region by accumulating carriers in both p and n type regions. We also verify the optoelectronic characteristics by disclosing the related physical mechanisms behind the light emission phenomena. The emission of visible light by a monolithically integrated Si diode under the reverse bias is also discussed. The light is emitted as spatial sources by the defects located at the p-n junction of the reverse-biased diode. The influence of the defects on the electrical behavior is manifested as a current-dependent electroluminescence.

关键词： silicon light-emitting diode reverse bias electro-optic modulation

基于一个大型随机试验预测稳定性心绞痛队列患者死亡、心肌梗死和卒中的危险评分

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英国医学杂志中文版 2006年第1期9卷 16-19页

作者： Tim C Clayton Stuart J Pocock jacobus Lubsen Zoltán Vokó Bridget-Anne Kirwan Keith A A Fox Philip A Poole-Wilson Department ofEpidemiology andPopulation Health London School of Hygiene andTropical MedicineLondon Department of Epidemiology and Biostatistics Erasmus Medical Centre 3000 DR Rotterdam Netherlandsprofessor School of Public Health University of Debrecen H-4028 Debrecen Hungary assistant professor SOCAR Research SA PO Box 2564 CH-1260 Nyon 2 Switzerland director Cardiovascular Research Unit EdinburghUniversityEdinburghEH16 4SBprofessor CardiovascularSciences NationalHeart and LungInstitute ImperialCollege LondonLondon SW3 6LYprofessor

目的对需要抗心绞痛治疗并且左心室功能代偿症状稳定的心绞痛患者建立预测全因死亡、心肌梗死和导致致残性卒中的复合危险评分。设计大型多中心临床试验数据的多变量Cox回归分析。背景西欧、以色列、加拿大、澳大利亚和新西兰的心脏专... 详细信息

目的对需要抗心绞痛治疗并且左心室功能代偿症状稳定的心绞痛患者建立预测全因死亡、心肌梗死和导致致残性卒中的复合危险评分。设计大型多中心临床试验数据的多变量Cox回归分析。背景西欧、以色列、加拿大、澳大利亚和新西兰的心脏专科门诊患者。入选者7311例具有全部需要资料的患者被入选。主要结局的测量指标平均随访4.9年时间内所有原因的死亡、心肌梗死或者致残性卒中。结果1063例患者发生任何原因死亡或者持久性心肌梗死或者致残性卒中。这些复合终点的5年危险性在危险性最低的十分位患者为4%,而在危险性最高的十分位患者为35%。危险评分结合16项临床常规变量的降序排序是:年龄、左心室射血分数、吸烟、白细胞计数、糖尿病、随机血糖浓度、肌酐浓度、既往卒中病史、1周至少1次心绞痛发作、冠状动脉造影发现(如果能够获得)、降脂治疗、QT间期、收缩期血压≥150mmHg、抗心绞痛药物数量、陈旧性心肌梗死以及性别。把这个模型分别应用于任何原因所致的死亡、心肌梗死和卒中进行预测评估,所得的结果相似。危险评分似乎不能预测事件性质(39%的死亡、46%心肌梗死以及15%致残性卒中)或者冠状动脉造影或血管重建率(占29%的患者)。结论该危险评分对客观地决定稳定性心绞痛患者进一步治疗措施以减少重要预后事件发生是有帮助的。该危险评分同样可以用于将来的计划性试验。

关键词：陈旧性心肌梗死心绞痛患者稳定性心绞痛冠状动脉造影危险评分随机试验血管重建治疗措施卒中预测

Chronic antiepileptic drug use and functional network efficiency: A functional magnetic resonance imaging study

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World Journal of Radiology 2017年第6期9卷 287-294页

作者： Tamar M van Veenendaal Dominique M IJff Albert P Aldenkamp Richard H C Lazeron Paul A M Hofman Anton J A de Louw Walter H Backes jacobus F A Jansen School for Mental Health and neuroscience Maastricht University Departments of Radiology and nuclear Medicine Maastricht University Medical Center Departments of neurology and neuropsychology Epilepsy Center Kempenhaeghe Department of neurology Gent University Hospital Department of neurology Maastricht University Medical Center Faculty of Electrical Engineering University of Technology Eindhoven

AIM To increase our insight in the neuronal mechanisms underlying cognitive side-effects of antiepileptic drug(AED) *** The relation between functional magnetic resonance-acquired brain network measures, AED use, and cognitive function was investigated. Three groups of patients with epilepsy with a different risk profile for developing cognitive side effects were included: A "low risk" category(lamotrigine or levetiracetam, n=16), an "intermediate risk" category(carbamazepine, oxcarbazepine, phenytoin, or valproate, n=34) and a "high risk" category(topiramate, n=5). Brain connectivity was assessed using resting state functional magnetic resonance imaging and graph theoretical network analysis. The Computerized Visual Searching Task was used to measure central information processing speed, a common cognitive side effect of AED treatment. RESULTS Central information processing speed was lower in patients taking AEDs from the intermediate and high risk categories, compared with patients from the low risk category. The effect of risk category on global efficiency was significant(P nCOVA), with a significantly higher global efficiency for patient from the low category compared with the high risk category(P no significant effect on the clustering coefficient(AnCOVA, P > 0.2). Also no significant associations between information processing speed and global efficiency or the clustering coefficient(linear regression analysis, P > 0.15) were observed. COnCLUSIOn Only the four patients taking topiramate show aberrant network measures, suggesting that alterations in functional brain network organization may be only subtle and measureable in patients with more severe cognitive side effects.

关键词： Antiepileptic drugs Cognitive side effects Brain networks Resting state Functional magnetic resonance imaging Graph analysis