Modeling the Cost Effectiveness of Malaria Control Interventions in the Highlands of Western Kenya

Introduction

Tools that allow for in silico optimization of available malaria control strategies can assist the decision-making process for prioritizing interventions. The OpenMalaria stochastic simulation modeling platform can be applied to simulate the impact of interventions singly and in combination as implemented in Rachuonyo South District, western Kenya, to support this goal.

Methods

Combinations of malaria interventions were simulated using a previously-published, validated model of malaria epidemiology and control in the study area. An economic model of the costs of case management and malaria control interventions in Kenya was applied to simulation results and cost-effectiveness of each intervention combination compared to the corresponding simulated outputs of a scenario without interventions. Uncertainty was evaluated by varying health system and intervention delivery parameters.

Results

The intervention strategy with the greatest simulated health impact employed long lasting insecticide treated net (LLIN) use by 80% of the population, 90% of households covered by indoor residual spraying (IRS) with deployment starting in April, and intermittent screen and treat (IST) of school children using Artemether lumefantrine (AL) with 80% coverage twice per term. However, the current malaria control strategy in the study area including LLIN use of 56% and IRS coverage of 70% was the most cost effective at reducing disability-adjusted life years (DALYs) over a five year period.

Conclusions

All the simulated intervention combinations can be considered cost effective in the context of available resources for health in Kenya. Increasing coverage of vector control interventions has a larger simulated impact compared to adding IST to the current implementation strategy, suggesting that transmission in the study area is not at a level to warrant replacing vector control to a school-based screen and treat program. These results have the potential to assist malaria control program managers in the study area in adding new or changing implementation of current interventions.     

杂质对蛋白质晶体影响研究进展

综述了杂质对蛋白质晶体生长影响研究领域的进展情况. 对可能的杂质来源以及杂质对结晶过程的影响进行了介绍.重点介绍了和结晶蛋白质分子结构相似的杂质分子的影响, 包括晶体成核、生长形态、表面形貌、生长动力学、质量等,以及杂质在晶体中的重新分配.     

Statistical Modeling Reveals the Effect of Absolute Humidity on Dengue in Singapore

Weather factors are widely studied for their effects on indicating dengue incidence trends. However, these studies have been limited due to the complex epidemiology of dengue, which involves dynamic interplay of multiple factors such as herd immunity within a population, distinct serotypes of the virus, environmental factors and intervention programs. In this study, we investigate the impact of weather factors on dengue in Singapore, considering the disease epidemiology and profile of virus serotypes. A Poisson regression combined with Distributed Lag Non-linear Model (DLNM) was used to evaluate and compare the impact of weekly Absolute Humidity (AH) and other weather factors (mean temperature, minimum temperature, maximum temperature, rainfall, relative humidity and wind speed) on dengue incidence from 2001 to 2009. The same analysis was also performed on three sub-periods, defined by predominant circulating serotypes. The performance of DLNM regression models were then evaluated through the Akaike''s Information Criterion. From the correlation and DLNM regression modeling analyses of the studied period, AH was found to be a better predictor for modeling dengue incidence than the other unique weather variables. Whilst mean temperature (MeanT) also showed significant correlation with dengue incidence, the relationship between AH or MeanT and dengue incidence, however, varied in the three sub-periods. Our results showed that AH had a more stable impact on dengue incidence than temperature when virological factors were taken into consideration. AH appeared to be the most consistent factor in modeling dengue incidence in Singapore. Considering the changes in dominant serotypes, the improvements in vector control programs and the inconsistent weather patterns observed in the sub-periods, the impact of weather on dengue is modulated by these other factors. Future studies on the impact of climate change on dengue need to take all the other contributing factors into consideration in order to make meaningful public policy recommendations.     

学习障碍儿童的弹性发展研究

学习障碍是学龄儿童较常见的问题之一。近年来,西方学者在学习障碍领域开始引人弹性发展理论,取得了大量的研究成果。本文就弹性发展理论的内容、影响学习障碍儿童弹性发展的保护性因素和危险性因素、弹性发展的作用机制以及学习障碍儿童的弹性干预作了简要的介绍,以期对我国的学习障碍研究和干预有所启发。     

The Effectiveness of Public Health Interventions to Reduce the Health Impact of Climate Change: A Systematic Review of Systematic Reviews

Background

Climate change is likely to be one of the most important threats to public health in the coming years. Yet despite the large number of papers considering the health impact of climate change, few have considered what public health interventions may be of most value in reducing the disease burden. We aimed to evaluate the effectiveness of public health interventions to reduce the disease burden of high priority climate sensitive diseases.

Methods and Findings

For each disease, we performed a systematic search with no restriction on date or language of publication on Medline, Web of Knowledge, Cochrane CENTRAL and SCOPUS up to December 2010 to identify systematic reviews of public health interventions. We retrieved some 3176 records of which 85 full papers were assessed and 33 included in the review. The included papers investigated the effect of public health interventions on various outcome measures. All interventions were GRADE assessed to determine the strength of evidence. In addition we developed a systematic review quality score. The interventions included environmental interventions to control vectors, chemoprophylaxis, immunization, household and community water treatment, greening cities and community advice. For most reviews, GRADE showed low quality of evidence because of poor study design and high heterogeneity. Also for some key areas such as floods, droughts and other weather extremes, there are no adequate systematic reviews of potential public health interventions.

Conclusion

In conclusion, we found the evidence base to be mostly weak for environmental interventions that could have the most value in a warmer world. Nevertheless, such interventions should not be dismissed. Future research on public health interventions for climate change adaptation needs to be concerned about quality in study design and should address the gap for floods, droughts and other extreme weather events that pose a risk to health.     

赤眼蜂防治小菜蛾问题

赤眼蜂Ｔｒｉｃｈｏｇｒａｍｍａ（Ｔ．ｃｏｎｆｕｓｕｍＶｉｇｇｉａｎｉ,＝Ｔ．ｃｈａｌｏｎｉｓ,Ｎａｇａｒａｊａ,ｎｅｃ．Ｉｓｈｕ）于卵期降低小菜蛾Ｐｌｕｔｅｌｌａｘｙｌｏｓｔｅｌｌａ（Ｌ．）种群密度,但对其幼虫期的天敌不会随即受到影响,相对地提高了天敌的作用。本文在生命表的基础上应用于扰作用控制抬数评价这两者的相辅相成的效果。试验分析结果表明,赤眼蜂对小菜蛾种群动态的控制作用是比较明显的。小菜蛾的产卵高峰期比较长,卵的发育历期比较短,这是应用赤眼蜂的不利条件．赤眼蜂成虫散放后继续扩散,同时不可避免逐日死亡,这也不利于寄生率的提高。本文通过对赤眼蜂成虫扩散行为的观察,结合小菜蛾的上述特点,讨论提高赤眼蜂对小菜蛾防治效果的措施。     

环境因子对药用植物药材形成的影响研究进展

药用植物是中药资源库的重要组成部分,药用植物中有效成分含量的高低是评鉴药材质量优劣的重要标准之一,而环境因子在药材形成过程中起着决定性作用,适宜的生长环境能促进药材中有效成分的合成与积累,从而提高药材质量。本文就近10年来国内外对光照、水分、温度等环境因子对药用植物质量影响的研究文献进行综述,为药用植物优质药源基地建设关键技术研究提供思路。     

染料的生物降解研究

生物降解法是染料污染治理的重要方法。针对目前使用量较大的偶氮染料、二苯基甲烷染料和蒽醌染料这3大类染料,重点介绍了厌氧和好氧条件下的偶氮还原及其机理、三苯基甲烷染料降解菌和蒽醌染料降解菌的研究进展。     

Pyrosequencing Reveals the Influence of Organic and Conventional Farming Systems on Bacterial Communities

It has been debated how different farming systems influence the composition of soil bacterial communities, which are crucial for maintaining soil health. In this research, we applied high-throughput pyrosequencing of V1 to V3 regions of bacterial 16S rRNA genes to gain further insight into how organic and conventional farming systems and crop rotation influence bulk soil bacterial communities. A 2×2 factorial experiment consisted of two agriculture management systems (organic versus conventional) and two crop rotations (flax-oat-fababean-wheat versus flax-alfalfa-alfalfa-wheat) was conducted at the Glenlea Long-Term Crop Rotation and Management Station, which is Canada’s oldest organic-conventional management study field. Results revealed that there is a significant difference in the composition of bacterial genera between organic and conventional management systems but crop rotation was not a discriminator factor. Organic farming was associated with higher relative abundance of Proteobacteria, while Actinobacteria and Chloroflexi were more abundant in conventional farming. The dominant genera including Blastococcus, Microlunatus, Pseudonocardia, Solirubrobacter, Brevundimonas, Pseudomonas, and Stenotrophomonas exhibited significant variation between the organic and conventional farming systems. The relative abundance of bacterial communities at the phylum and class level was correlated to soil pH rather than other edaphic properties. In addition, it was found that Proteobacteria and Actinobacteria were more sensitive to pH variation.     

植物的硅素营养研究综述

本文阐述了硅在植物中的形态、分布、吸收、积累、生理作用及其与其它元素的关系。研究表明：1．硅主要以二氧化硅胶(SiO2.nH2O)的无机物形态存在于植物表皮细胞和细胞壁。植物体内硅的含量在不同物种间差异很大。根据硅的含量,可将一般栽培植物分为三种类群;同时根据植物硅钙摩尔比值可将植物分为喜硅植物和非喜硅植物。硅在植物各部分分布不均匀,并且随着植株的生长发育,植株中的硅含量不断变化。植物中硅的积累受环境中多种因素的影响。2．植物主要以单硅酸形态吸收硅,不同植物吸收硅的能力不同。水稻具有主动吸硅能力,其吸收过程受体内代谢活动影响<请合法使用软件>其它大多数植物主要以被动方式吸收硅,但不排除具有选择性吸收硅的可能性。3．硅对植物的生长发育产生影响。硅是一些植物(如禾本科植物、甜菜、木贼属植物及某些硅藻)的必需元素。硅对其它很多植物具有有益作用。硅对植物的作用主要表现在对形态结构、生理过程和抗逆能力三方面的影响 上。在去硅条件下,多种植物表现出缺硅症状。4．硅对植物吸收利用对其它营养元素产生影响。硅对不同元素的影响方式和程度不同,同时随着植物的生长发育,对某种元素的作用常发生变化。     

Meta-analysis Reveals Potential Influence of Oxidative Stress on the Airway Microbiomes of Cystic Fibrosis Patients

The lethal chronic airway infection of the cystic fibrosis (CF) patients is predisposed by colonization of specific CF-philic pathogens or the CF microbiomes, but key processes and reasons of the microbiome settlement in the patients are yet to be fully understood, especially their survival and metabolic dynamics from normal to diseased status under treatment. Here, we report our meta-analysis results on CF airway microbiomes based on metabolic networks reconstructed from genome information at species level. The microbiomes of CF patients appear to engage much more redox-related activities than those of controls, and by constructing a large dataset of anti-oxidative stress (anti-OS) genes, our quantitative evaluation of the anti-OS capacity of each bacterial species in the CF microbiomes confirms strong conservation of the anti-OS responses within genera and also shows that the CF pathogens have significantly higher anti-OS capacity than commensals and other typical respiratory pathogens. In addition, the anti-OS capacity of a relevant species correlates with its relative fitness for the airways of CF patients over that for the airways of controls. Moreover, the total anti-OS capacity of the respiratory microbiome of CF patients is collectively higher than that of controls, which increases with disease progression, especially after episodes of acute exacerbation and antibiotic treatment. According to these results, we propose that the increased OS in the airways of CF patients may play an important role in reshaping airway microbiomes to a more resistant status that favors the pre-infection colonization of the CF pathogens for a higher anti-OS capacity.     

Thermodynamic Analysis of the Binding of 2F5 (Fab and Immunoglobulin G Forms) to Its gp41 Epitope Reveals a Strong Influence of the Immunoglobulin Fc Region on Affinity

Immunotherapies and vaccines based on the induction of broadly neutralizing monoclonal antibodies (bNAbs) have become outstanding strategies against HIV-1. Diverse bNAbs recognizing different regions of the HIV-1 envelope have been identified and extensively studied. However, there is little information about the thermodynamics of binding of these bNAbs and their epitopes. We used isothermal titration calorimetry to characterize thermodynamically the interactions between bNAb 2F5 (in both the IgG and Fab forms) and its functional and core epitope peptides. We found that these interactions are enthalpically driven and opposed by a negative entropy change. The highest affinity was found for 2F5 IgG for its functional epitope, indicating that additional interactions involving residues flanking the core epitope contribute strongly to higher affinity. In addition, the strong influence of the Fc region on the binding affinity suggests long-range allosteric effects within IgG. Our results provide useful information for developing new therapeutics against HIV-1 and, in a broader scope, contribute to a better understanding of antigen-antibody recognition.     

基于层次分析法的67种爵床科植物观赏价值综合评价

基于中国科学院西双版纳热带植物园收集保存的爵床科植物资源,运用层次分析法构建评价体系,对67种具有园林应用潜力的爵床科植物进行观赏价值综合评价。结果表明,在一级指标中,花观赏性所占权重最大,表示花观赏性在爵床科植物观赏价值综合评价中是最重要的方面;在二级指标中,花(序)量、花(序)色鲜艳度和盛花期时长对爵床科植物观赏价值的影响权重均超过10%,对评价结果有较大影响,而花(序)大小、花后观赏性和叶片盖度对爵床科植物观赏价值的影响权重均低于5%,对评价结果影响较小。依据指标权重和评分标准,对67种爵床科植物的观赏价值进行综合评分并划分等级,赤苞花(Megaskepasma erythrochlamys)、宽叶十万错(Asystasia gangetica)、鸟尾花(Crossandra infundibuliformis)、翠芦莉(Ruellia simplex)、翼叶山牵牛(Thunbergia alata)、金苞花(Pachystachys lutea)、黄花老鸦嘴(Thunbergia mysorensis)、白苞爵床(Justicia betonica)、叉花草(Strobilanthes hamiltoniana)、绯红珊瑚花(Pachystachys coccinea)、白金羽花(Schaueria calytricha)、山牵牛(Thunbergia grandiflora)等12种植物的观赏价值较高,综合评价等级为Ⅰ级,具有较好的园林应用前景。     

Modeling HIV Vaccines in Brazil: Assessing the Impact of a Future HIV Vaccine on Reducing New Infections,Mortality and Number of People Receiving ARV

Background

The AIDS epidemic in Brazil remains concentrated in populations with high vulnerability to HIV infection, and the development of an HIV vaccine could make an important contribution to prevention. This study modeled the HIV epidemic and estimated the potential impact of an HIV vaccine on the number of new infections, deaths due to AIDS and the number of people receiving ARV treatment, under various scenarios.

Methods and Findings

The historical HIV prevalence was modeled using Spectrum and projections were made from 2010 to 2050 to study the impact of an HIV vaccine with 40% to 70% efficacy, and 80% coverage of adult population, specific groups such as MSM, IDU, commercial sex workers and their partners, and 15 year olds. The possibility of disinhibition after vaccination, neglecting medium- and high-risk groups, and a disease-modifying vaccine were also considered. The number of new infections and deaths were reduced by 73% and 30%, respectively, by 2050, when 80% of adult population aged 15–49 was vaccinated with a 40% efficacy vaccine. Vaccinating medium- and high-risk groups reduced new infections by 52% and deaths by 21%. A vaccine with 70% efficacy produced a great decline in new infections and deaths. Neglecting medium- and high-risk population groups as well as disinhibition of vaccinated population reduced the impact or even increased the number of new infections. Disease-modifying vaccine also contributed to reducing AIDS deaths, the need for ART and new HIV infections.

Conclusions

Even in a country with a concentrated epidemic and high levels of ARV coverage, such as Brazil, moderate efficacy vaccines as part of a comprehensive package of treatment and prevention could have a major impact on preventing new HIV infections and AIDS deaths, as well as reducing the number of people on ARV. Targeted vaccination strategies may be highly effective and cost-beneficial.     

遗鸥研究概述

叙述自遗鸥（Larus relictus)被确认为有效物种以来30余年中世界范围内对遗鸥的主要研究结果与对遗鸥认知发展的概况,总的来讲,遗鸥作为环蒙古高原的繁殖分布,为荒漠-半荒漠生态条件下的典型鸟种,具4个相对独立的繁殖种群,取湖心岛为繁殖生境,遗鸥当年幼鸟呈辐射方式作最初扩散。而其主要越冬地和越冬种群至今尚不明了,由于气候变化造成繁殖生境的不稳定,应是导致遗鸥繁殖群呈较强动态变化的重要原因。     

基于子图模式的巨强连通体局域结构特征(英文)

对代谢网络的"蝴蝶结"结构进行研究吸引了众多科研人员的关注。当前,基于复杂网络理论的全局拓扑结构特征已经被广泛用于研究这种"蝴蝶结"结构的组织原则,然而基于局域结构特征的研究相对较少。本文分析了10种有机物代谢网络及其相应的巨强连通体部分的网络模体(即频繁的子图)。结果显示代谢网络及其相应的巨强连通体部分的网络模体非常相似,这从局域结构特征的角度论证了代谢网络巨强连通体部分的重要性。