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几种主要水化学因素对典型重金属水生生物毒性的影响分析

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中国环境科学 2024年第7期44卷 4071-4083页

作者：王昕噶玛扎西石文卿程英豪许子寒郭伟王颖北京航空航天大学材料科学与工程学院北京100191 北京航空航天大学空间与环境学院北京100191 生态环境部核与辐射安全中心北京100082 北京师范大学水科学研究院北京100875 中国环境科学研究院环境基准与风险评估国家重点实验室北京100012 北京市水文总站北京100089

为阐明不同水化学条件对水体中重金属生物毒性的影响,本研究探究了pH值、硬度、温度和有机碳(OC)四个主要水化学因素对4种典型重金属引起不同类别水生生物急、慢性毒性的影响.结果表明,单一水化学因素对不同金属的水生生物毒性影响存在... 详细信息

为阐明不同水化学条件对水体中重金属生物毒性的影响,本研究探究了pH值、硬度、温度和有机碳(OC)四个主要水化学因素对4种典型重金属引起不同类别水生生物急、慢性毒性的影响.结果表明,单一水化学因素对不同金属的水生生物毒性影响存在较大差异;硬度和OC的升高会使得鱼类的水生生物毒性降低;温度的升高则会增加鱼类、昆虫的水生生物毒性.对不同类别的生物,单一水化学因素的毒性影响不同.考虑综合水化学因素的影响时,水生生物急性毒性和慢性毒性受到的影响效果显著不同;综合因素中OC可能是影响毒性的重要因子.

关键词：重金属水生生物水化学因素毒性影响

Twenty years of misdiagnosis of schizophrenia in a patient with Dandy-Walker variant syndrome

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General Psychiatry 2019年第1期32卷 46-48页

作者： Joao gama Marques Hospital Julio de Matos Centro Hospitalar Psiquiatrico de LisboaClinica Universitaria de Psiquiatriae Psicologia MedicaFaculdade de Medicina Universidade de LisboaLisboa Portugal

sUMMARY Various case reports of patients with Dandy-Walker variant syndrome mimicking schizophrenia have been published in the last 20 years, suggest!ng that this neurodevelopment disorder should be part of the differential diagnosis for every patient with a first episode of psychosis. In this report, it is presented that a patient who was diagnosed and treated as a paranoid schizophrenic for 20 years and had four bone fractures secondary to ataxic gait impairment, before performing a neuroimaging examination that revealed Dandy-Walker variant syndrome.

关键词： Twenty years misdiagnosis schizophrenia

Investigation of normal,lateral,and oblique impact of microscale projectiles into unidirectional glass/epoxy composites

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Defence Technology（防务技术） 2022年第11期18卷 1960-1978页

作者： Christopher s.Meyer Isabel G.Catugas John W.Gillespie Jr. Bazle Z.gama Haque University of Delaware Center for Composite Materials(UD-CCM) 101 Academy StreetNewarkDE19716USA

spacesuits and spacecraft must endure high velocity impacts from micrometeoroids. This work considers the impact of 100 μm diameter projectiles into composite targets at velocities from 0.5 km/s to 2 km/*** work begins by presenting an energy-based theoretical model relating depth of penetration(Do P)and impact force to impact velocity, characteristic time, and threshold velocity and force. Next, this work compares numerical simulations of normal impact on composites to the theoretical model. Numerical simulations are conducted with Ls-DYNA and the well-known composite model, MAT-162. The numerical models consider unidirectional s2-glass fiber reinforced sC-15 epoxy composite laminates. The numerical model shows good correlation with the theoretical model. The numerical model also investigates lateral impact, parallel to the fiber direction, and oblique impact at angles from 30°to 82.5°.This work decomposes oblique impact into normal and lateral components, and compares them with normal and lateral impact results. The results show good correlation of the normal component of oblique results with the theoretical model. This numerical and theoretical study focuses on Do P, velocity, and penetration resistance force as functions of time. The theoretical model and numerical simulations are used to determine new Do P parameters: characteristic time of depth of penetration and threshold impact velocity. These models are a first step in developing the capability to predict Do P for oblique,microscale, high-speed impact on composite materials.

关键词： Microscale Hypervelocity impact Composites Erosion Penetration

Easy proft maximization method for open-pit mining

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Journal of Rock Mechanics and Geotechnical Engineering 2013年第5期5卷 350-353页

作者： C.dinis da gama IsT – Technical University of Lisbon

A methodology applicable at any phase of a surface mining project for evaluating its current technical and economic feasibility is *** requires the typically available quantitative data on the ore-body,with its three-dimensional block model developed upon accurate *** it allows estimations of exploitable reserves in function of various cut-off grades,such as the average grade of mineable ore,the tonnages of ore and waste rock,stripping ratios and proft estimates for different production *** cost evaluations of essential mine operations are available(such as ore mining,waste removal,ore concentration,transportation,indirect project costs and expected concentrate selling prices),the methodology will provide clear indications on the economic feasibility of mining,including the best available options at any *** expressions are developed on the basis of a proft mathematical function and an application example is presented with data available from an existing iron ore deposit.

关键词： Open-pit Proft maximization Ore grade stripping ratio Economic feasibility

Carbon and nitrogen mineralization in soil of leguminous trees in a degraded pasture in northern Rio de Janeiro, Brazil

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Journal of Forestry Research 2016年第1期27卷 91-99页

作者： Danielle A. D. Nunes Emanuela F. gama-Rodrigues Patricia A. B. Barreto[ Antonio C. gama-Rodrigue Paulo H. M. Monroe Chemistry school Rio de Janeiro Federal UniversityRio de Janeiro RJ 21941-909 Brazil soil Laboratory North Fluminense State UniversityCampos dos Goytacazes RJ 28013-602 Brazil Department of soil and Agricultural Engineering State University of Southwest Bahia Vitoda da ConquistaBA 45031-300 Brazil

Use of legume trees can improve soil quality in degraded pastures. The aim of this study was to charac- terize C and N mineralization kinetics and estimate the potentially mineralizable C and N in soil under Mimosa caesalpiniifolia Benth. and Acacia auriculiformis A. Cunn. ex Benth. secondary forest and pasture in red-yellow latosols in southeast Brazil. We conducted a laboratory aerobic incubation experiment using a completely ran- domized design of four replicates and four types of plant cover using a modified version of the stanford and smith technique （1972） to study C and N mineralization potential. Potentially mineralizable N （No） ranged from 135 to 170 mg kg-1. The predominant form of mineral N for all types of plant cover was N-NO3-. M. caesalpiniifolia was the only species that had a positive influence on N min- eralization. Neither of the legumes influenced C mineral- ization in pasture or secondary forest. The model of N mineralization corresponded to a sigmoidal curve while C mineralization corresponded to an exponential curve, revealing that the N and C mineralization processes were distinct. N mineralized by M. caesalpiniifolia （216 kg ofN ha-1） was adequate to meet the N requirement for a livestock-forest system.

关键词： Carbon dioxide Forest soil Mineralized N Organic matter soil microorganisms

surgical risk for patients with Chagasic achalasia and its correlation with the degree of esophageai dilation

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World Journal of Gastroenterology 2005年第37期11卷 5840-5844页

作者： José Garcia Neto Roberto de Cleva Bruno Zilberstein Joaquim José gama-Rodrigues surgery Division Hospital das Clínicas Federal University of Goiás Medical School Goiás Brazil Gastroenterology Department Digestive Tract surgery Division Hospital das Clínicas University of Sao Paulo Medical School So Paulo Brazil

AIM： To analyze the risk of cardiovascular complications in patients with indication for surgical treatment of Chagasic esophageal achalasia and to correlate the surgical risks with the degree of esophageal dilation, thereby proposing a risk scale index. METHODs： One hundred and twenty-four patients with Chagasic esophageal achalasia, who received surgical treatment at the Hospital das Clinicas of the Federal University of Goiás, were included in this study. The patients were mostly related to the postoperative complications due to the cardiovascular system. All the patients were submitted to：（1） clinical history to define the cardiac functional class （New York Heart Association）; （2） conventional 12-lead electrocardiogram at rest; and （3） contrast imaging of the esophagus to determine esophageal dilatation according to Rezende＇s classification of Chagasic megaesophagus. REsULTs： An assessment of the functional classification （FC） of heart failure during the preoperative period determined that 67 patients （54.03%） were assigned functional class Ⅰ （FC Ⅰ）, 46 patients （37.09%） were assigned functional class Ⅱ （FC Ⅱ）, and 11 patients （8.87%） were assigned functional class Ⅲ （FC Ⅲ）. None of the patients were assigned to functional class Ⅳ （FC Ⅳ）. There was a positive correlation between the functional class and the postoperative complications （FC Ⅰ×FC Ⅱ： P〈0.001; FC Ⅰ×FC Ⅲ： P〈0.001）. The ECG was normal in 44 patients （35.48%） and presented abnormalities in 80 patients （64.52%）. There was a significant statistical correlation between abnormal ECG （arrhythmias and primary change in ventricular repolarization） and postoperative complications （P〈0.001）. With regard to the classification of the Chagasic esophageal achalasia, the following distribution was observed： group Ⅱ, 53 patients （42.74%）; group Ⅲ, 37 patients （29.83%）; and group Ⅳ, 34 patients （27.41%）. There was a positive correlation between the degree of esophageal dilation and the increase in postoperative compli

关键词： Postoperative Chagas' disease surgical risk Chagasic achalasia Cardiovascular risk

Toxicity studies for indigenous Bacillus thuringiensis isolates from Malang city,East Java on Aedes aegypti larvae

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Asian Pacific Journal of Tropical Biomedicine 2013年第2期3卷 111-117页

作者： Zulfaidah Penata gama Nobukazu Nakagoshi suharjono Faridah setyowati Graduate school for International Development(IDEC) Hiroshima University Department of Biology Faculty of ScienceBrawijaya University

Objective:To investigate the toxicity of indigenous Bacillus thuringiensis（***）isolates from Malang City for controlling Aedes aegypti（***）***:soil samples were taken from Purwantoro and sawojajar *** isolation was performed using *** selective *** characteristics of the isolates were obtained with the simple matching *** growth and prevalence of spores were determined by the Total Plate Count method,and toxicity tests were also performed on the third instar larval stage of *** percentage of larval mortality was analysed using probit *** LC50was analysed by ANOVA,and the Tukey HsD interval was 95%.Results:Among the 33 selected bacterial isolates,six were obtained（PWR4-31,PWR4-32,sWJ4-2b,sWJ4-4b,sWJ-4k and sWJ5-1）that had a similar phenotype to reference *** on the dendrogram,all of the bacterial isolates were 71%*** isolates that had a higher prevalence of reference *** were PWR4-32,sWJ4-4b and sW5-1,of which the spore prevalence was 52.44%,23.59%,34.46%,*** three indigenous isolates from Malang City successfully killed *** *** PWR4-32 isolates were the most effective at killing the ***:six indigenous *** isolates among the 33 bacterial isolates found in the sawojajar and Purwantoro sub-districts were toxic to the third instar larvae of *** PWR4-32 isolates were identical to tbe reference *** and had 88%phenotype *** PWR4-32 isolates had the highest spore prevalence（52.44%）,and the early stationary phase occurred at 36 *** PWR4-32 isolates were the most effective at killing *** larvae(LC50-72 h=2.3×108 cells/mL).

关键词： Aedes aegypti Bacillus thuringiensis LC_(50) Toxicological studies

Comparative stability analyses of traditional and selective room-and-pillar mining techniques for sub-horizontal tungsten veins

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International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 1-8页

作者： Vidal Felix Navarro Torres Carlos dinis da gama Matilde Costa e silva Paula Falcao Neves Qiang Xie Mining and Geo-resources Engineering Department of IsT Technical University of Lisbon 1049-001 Portugal Faculty of Civil Engineering Chongqing University Chongqing 400045 China

The stability and productivity concerning a modification on the traditional room and pillar for a new selective technique at the Portuguese Panasqueira Mine have been *** traditional room-and-pillar stoping uses 5.0-m wide rooms with 3.0 m×3.0 m pillars,while the selective room-and-pillar mining technique consists in stoping with rooms of 4.0 m wide and pillars of 4 m×4 m with a subsequent selective cutting of the quartz veins at the mid pillar of approximately 0.5 m high,to obtain a pillar section with an area of 3.0 m×3.0 *** stability and productivity analyses indicate that the selective technique obtains smaller average pillar safety factor,more rock mass displacement,more extraction and selectivity ratios,and ore grade improvement,compared with the traditional *** results show that the selective technique is also more *** proposed selective room-and-pillar mining technique is applicable to any sub-horizontal narrow quartz veins with wolfram,gold,*** as the famous La Rinconada gold mine in the Peruvian Andes.

关键词： mines and mining tungsten deposits productivity stability stoping

sARs-CoV-2 infection in liver transplant recipients:A complex relationship

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World Journal of Gastroenterology 2021年第44期27卷 7734-7738页

作者： Ricardo Wesley Alberca Gil Benard Gabriela gama Freire Alberca Maria Notomi sato Laboratorio de Dermatologia e Imunodeficiencias(LIM-56) Departamento de Dermatologia e Institute de Medicina TropicalFaculdade de Medicina FMUSPUniversidade de São PauloSão Paulo 01246-903Brazil Laboratorio de Dermatologia e Imunodeficiencias(LIM-56) Departamento de DermatologiaFaculdade de Medicina FMUSPUniversidade de São PauloSão Paulo 01246-903Brazil

The recent manuscript reviewed investigations involving liver damage in coronavirus disease 2019(COVID-19)patients,and COVID-19 in patients with previous chronic hepatological diseases,such as patients with liver *** literature presents several conflicting results concerning the anti-sARs-CoV-2 response in patients with solid organ transplants,in liver transplant ***,we would like to humbly state a few points for consideration involving liver transplant recipients and COVID-19,such as the time since transplantation,comorbidities,and immunosuppressive regimens.

关键词： COVID-19 sARs-CoV-2 Liver transplant Immunosuppression Infection Comorbidities