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Calcium Phosphate Biomaterials: An Update

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Journal of Wuhan University of technology(Materials Science) 2005年第B12期20卷 1-6页

作者： Racquel Z LeGeros john P LeGeros New York University College of Dentistry New York 10010 USA

Current calcium phosphate （ CaP ） biomaterials for bone repair, substitution, augmentation and regeneration include hydroxyapatite （ ha ） from synthetic or biologic origin, beta-tricaicium phosphate （ β- tCP ）, biphasic calcium phosphate （BCP）, and are available as granules, porous blocks, components of compashes （CaP/pollymer） cements, and as coatings on orthopedic and dental implants. Experimental calcium phosphate biomaterials include CO3^- and F-substituted apatites, Mg-and Zn-substituted β-tCP, calcium phosphate glasses, this paper is a brief review of the different types of CaP biomaterials and their properties such as bioactivity , osteoconductivity , osteoinductivity.

关键词： calcium phosphates ha β- tCP BCP calcium phosphate cement implant coatings bonegrafts

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电子产品多物理场耦合仿真方法研究

系统仿真学报 2010年第4期22卷 853-857页

作者：彭博杜平安夏汉良何凌川电子科技大学机械电子工程学院成都610054 嘉利环球科技有限公司东莞523709

多物理场耦合涉及机械、电磁、流体、热、声等学科,对产品性能有直接影响。针对电子产品,研究其共同属性、基本场及耦合模式、各场间耦合关系,提出一种面向电子产品的多场耦合协同仿真方法和仿真框架,并以机架式服务器为例,提出了协同... 详细信息

多物理场耦合涉及机械、电磁、流体、热、声等学科,对产品性能有直接影响。针对电子产品,研究其共同属性、基本场及耦合模式、各场间耦合关系,提出一种面向电子产品的多场耦合协同仿真方法和仿真框架,并以机架式服务器为例,提出了协同仿真流程和内容,并采用Pro/E、FLOthERM和FLUENt等软件进行了多场耦合仿真,特别是气—声耦合的噪声分析。仿真结果验证了多场耦合协同仿真方法,对预测和优化产品性能具有一定指导意义。

关键词：多场耦合建模耦合分析仿真

Mapping and Assessing typhoon-induced Forest Disturbance in Changbai Mountain National Nature Reserve Using time Series Landsat Imagery

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Journal of Mountain Science 2015年第2期12卷 404-416页

作者： GUO Xiao-yi ZhaNG hong-yan WANG Ye-qiao john Clark School of Geographical Sciences Northeast Normal University Department of Natural Resources Science University of Rhode Island

Monitoring forest disturbances is important for understanding changes in ecosystems. the 1986 typhoon Vera was a serious disturbance that severely impacted the forest ecosystems of Changbai Mountain National Nature Reserve. Although the typhoon disturbance occurred more than two decades ago, the effects of the typhoon still remain within the study area. Few studies have focused on mapping and assessing disturbances across broad spatial and temporal scales. For this study, we first generated a map of forest composition prior to the typhoon disturbance, which served as a baseline data for the extraction of disturbed area. then, the Disturbance Index(DI) method was tested for mapping the extent and magnitude of disturbance in the study area by applying a tasseled Cap transformation to the Landsat imagery. the Landsatbased DI method estimated that an area of 13,764.78 ha of forest was disturbed by the typhoon. Based on visual assessments, these results correspond closely with the reference map derived from ground surveys. these results also revealed the influence of local topographic features on the distribution of windthrow areas. Windthrow areas were more pronounced inareas with elevations ranging from 1,000 to 2,000 m, slopes of less than 10 degrees, and southwestern to northwestern aspects. In addition, the relatively long(25 years) post-typhoon recovery period assessed by this study provided a more comprehensive analysis of the dynamics of forest recovery processes over time. Windthrow areas did not recover immediately after the typhoon, likely due to forest management practices enacted at the time. So far, forest recovery has proceeded more rapidly at elevations below 1,400 m, particularly on western slopes within the study area. Finally, a time series of DI values within the study period suggests a secondary disturbance may have occurred between 2000 and 2001.

关键词： typhoon Vera Windthrow areas Disturbance Index(DI) topographic features Forest recovery process

Development and clinical trial of a novel bioactive bone cement

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Frontiers of Medicine 2008年第2期2卷 117-126页

作者： john CY LEONG Zhaoyang LI William W LU the Open University of hong Kong Hong Kong SAR.China Department of Orthopaedics and traumatology The University of Hong KongHong Kong SAR.China

Strontium(Sr)and related compounds have become more attractive in the prevention and treatment of ***,we developed a novel bioactive bone cement which is mainly composed of strontium-con-taining hydroxyapatite(Sr-ha)filler and bisphenol A diglycidylether dimethacrylate(Bis-GMA)*** bone cement is superior to conventional polymethylmethacrylate(PMMA)bone cement in bioactivity,biocompatibility,and *** also has shown sufficient mechanical strength properties for its use in percutaneous vertebro-plasty(PVP)and total hip replacement(thR).In this paper,we review the in vitro,in vivo and clinical evidence for the effectiveness of this bioactive bone cement.

关键词： Strontium osteoporosis bioactive bone cement vertebroplasty total hip replacement

the Enjoyment of Physical Activity Determines Body Mass Index in Young People with Physical Disabilities

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Open Journal of Preventive Medicine 2014年第5期4卷 241-249页

作者： Shirley S. M. Fong Amy S. C. ha tina W. t. Chan Mei K. Au Department of Sports Science and Physical Education The Chinese University of Hong Kong Hong Kong China Physiotherapy Department Hong Kong Red Cross John F. Kennedy Centre Hong Kong China Physiotherapy Department Kowloon Hospital Hong Kong China

Objective: this study aimed to 1) compare the body mass index (BMI) and patterns of out-of-school activity participation in young people with and without physical disabilities, and 2) examine the relationship between BMI and the activity participation patterns among young people with physical disabilities. Methods: thirty-nine young persons with physical disabilities (mean age ± standard deviation: 18.79 ± 1.99 years) and 70 healthy individuals (mean age ± standard deviation: 18.64 ± 0.74 years) participated in the study. the diversity, intensity, companionship, location and enjoyment of participation in activities were evaluated using the Children’s Assessment of Participation and Enjoyment (CAPE) scale. Body height and weight were obtained and BMI was calculated. Results: People with physical disabilities, regardless of their gender, had significantly lower CAPE-derived scores in almost all types of activity than the control participants (p tly higher in the group with physical disabilities than in the control group (p ther showed that the CAPE score for physical activity explained 17.2% of the variance in BMI (p = 0.021). Conclusion: Young people with physical disabilities generally had lower levels of activity participation and a higher BMI than their healthy counterparts. the perception of enjoyment during physical activities was an important determinant of BMI in this group of participants.

关键词： Exercise Obesity happiness Disabled Persons

th1 cytokines promote t-cell binding to antigen-presenting cells via enhanced hyaluronan production and accumulation at the immune synapse

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Cellular & Molecular Immunology 2010年第3期7卷 211-220页

作者： Paul L Bollyky Stephen P Evanko Rebecca P Wu Susan Potter-Perigo S Alice Long Brian Kinsella helena Reijonen Kelly Guebtner Brandon teng Christina K Chan Kathy R Braun john A Gebe Gerald t Nepom thomas N Wight Benaroya Research Institute SeattleWAUSA

hyaluronan(ha)production by dendritic cells(DCs)is known to promote antigen presentation and to augment t-cell activation and *** hypothesized that pericellular ha can function as intercellular‘glue’directly mediating t cell–DC *** primary human cells,we observed ha-dependent binding between t cells and DCs,which was abrogated upon pre-treatment of the DCs with 4-methylumbelliferone(4-MU),an agent which blocks ha ***,t cells regulate ha production by DCs via t cell-derived cytokines in a t helper(th)subset-specific manner,as demonstrated by the observation that cell-culture supernatants from th1 but not th2 clones promote ha *** effects were seen upon the addition of exogenous th1 cytokines,IL-2,interferon c(IFN-c)and tumor necrosis factor a(tNF-a).the critical factors which determined the extent of DC–t cell binding in this system were the nature of the pre-treatment the DCs received and their capacity to synthesize ha,as t-cell clones which were pre-treated with monensin,added to block cytokine secretion,bound equivalently irrespective of their th *** data support the existence of a feedforward loop wherein t-cell cytokines influence DC production of ha,which in turn affects the extent of DC–t cell *** also document the presence of focal deposits of ha at the immune synapse between t-cells and APC and on dendritic processes thought to be important in antigen *** data point to a pivotal role for ha in DC–t cell interactions at the IS.

关键词： dendritic cell hyaluronan immune synapse pericellular matrix th1

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酸气回注技术发展现状及其在中国的应用前景

天然气工业 2013年第1期33卷 105-111页

作者：王寿喜汤林 john Carroll 西安石油大学中国石油勘探与生产分公司 Gas Liquids Engineering Ltd.

零排放的酸气回注技术是一种替代硫磺回收工艺的经济可行的酸气处理方法,同时也是一个减少温室气体排放的环保方法。为此,总结了酸气回注技术的发展和应用现状,结合实例对酸气回注和硫磺回收进行了经济技术和环保对比分析,结果表明:酸... 详细信息

零排放的酸气回注技术是一种替代硫磺回收工艺的经济可行的酸气处理方法,同时也是一个减少温室气体排放的环保方法。为此,总结了酸气回注技术的发展和应用现状,结合实例对酸气回注和硫磺回收进行了经济技术和环保对比分析,结果表明:酸气回注方案的硫处理费用为1 270美元/t;而硫磺回收的硫处理费用为1 400美元/t,若进一步考虑CO2排放、硫磺销售等因素,其综合处理费用将超过1 779美元/t。同时,分析了酸气回注在中国的应用需求及条件,展望了该技术在中国的应用前景,指出在下述几种情况下,为了取得最好的经济和环保效益,酸气回注会是一个不错的选择:①老气田气质变化后,硫磺回收装置已不适应生产需要而需改造;②新开发气田太偏远或h2S含量太低,硫磺回收不经济或工艺技术不好解决;③部分新开发气田的天然气组成不稳定,进行硫磺回收投资大、风险高;④部分碳酸盐岩开发油田伴生气含h2S,但含量变化大,进行硫磺回收工艺选择难度大;⑤火驱开发油田和采用蒸汽辅助重力泄油开发的稠油油田,其伴生气中h2S含量大,但气量小,回收不经济;⑥低渗透油田用CO2提高采收率等。

关键词：酸气回注硫磺回收碳排放温室气体中国经济和环保效益

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论厄普代克《罗杰教授的版本》的叙述策略

南京师范大学文学院学报 2013年第3期 97-101页

作者：哈旭娴南京大学外国语学院江苏南京210037

《罗杰教授的版本》是美国作家约翰·厄普代克的"红字"三部曲中的一部,在作品的创作中,作家突破以往的创作风格,在叙事实验方面作了尝试。作者运用叙事视角的突破、人物品行中的缺陷的暴露、模糊叙述者与隐含作者伦理取位等叙事技巧,为... 详细信息

《罗杰教授的版本》是美国作家约翰·厄普代克的"红字"三部曲中的一部,在作品的创作中,作家突破以往的创作风格,在叙事实验方面作了尝试。作者运用叙事视角的突破、人物品行中的缺陷的暴露、模糊叙述者与隐含作者伦理取位等叙事技巧,为读者营造出叙述的不可靠性和含混性,从而赋予文本多义性和开放性。

关键词：《罗杰教授的版本》叙述策略

Seasonal exports of phosphorus from intensively fertilised nested grassland catchments

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Journal of Environmental Sciences 2013年第9期25卷 1847-1857页

作者： Ciaran Lewis Rashad Rafique Nelius Foley Paul Leahy Gerard Morgan john Albertson Sandeep Kumar Gerard Kiely Department of Civil and Environmental Engineering University College Cork Department of Microbiology and Plant Biology University of Oklahoma Environmental Research Institute University College Cork Aquatic Services Unit Environmental Research Institute University College Cork Department of Civil and Environmental Engineering Duke University Department of Plant Science South Dakota State University

We carried out a one year （2002） study of phosphorus （P） loss from soil to water in three nested grassland catchments with known P input in chemical fertilizer and animal liquid slurry applications. Chemical fertilizer was applied to the grasslands between March and September and animal slurry was applied over the twelve months. the annual chemical P fertilizer applications for the 17 and 211 ha catchments were 16.4 and 23.7 kg P/ha respectively and the annual slurry applications were 10.7 and 14.0 kg P/ha, respectively. the annual total phosphorus （tP） export in stream-flow was 2.61, 2.48 and 1.61 kg P/ha for the 17, 211 and 1524 ha catchments, respectively, compared with a maximum permissible （by regulation） annual export of ca. 0.35 kg P/ha. the export rate （ratio of P export to P in land applications） was 9.6% and 6.6% from the 17 and 211 ha catchments, respectively. On average, 70% of stream flow and 85% of the P export occurred during the five wet months （October to February） indicating that when precipitation is much greater than evaporation, the hydrological conditions are most favourable for P export. however the soil quality and land use history may vary the results. Particulate P made up 22%, 43% and 37% of the tP export at the 17, 211 and 1524 ha catchment areas, respectively. As the chemical fertilizer was spread during the grass growth months （March to September）, it has less immediate impact on stream water quality than the slurry applications. We also show that as the catchment scale increases, the P concentrations and P export decrease, confirming dilution due to increasing rural catchment size. In the longer term, the excess P from fertilizer maintains high soil P levels, an antecedent condition favourable to P loss from soil to water. this study confirms the significant negative water quality impact of excess P applications, particularly liquid animal slurry applications in wet winter months. the findings suggest that restricted P application in w

关键词： phosphorus fertilizer slurry exports grassland land management water quality eutrophication