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1.
Physical work, high ambient temperature and wearing protective clothing can elevate body temperature and cardiovascular strain sufficiently to degrade performance and induce heat-related illnesses. We have recently developed an Arm Immersion Cooling System (AICS) for use in military training environments and this paper will review literature supporting such an approach and provide details regarding its construction. Extremity cooling in cool or cold water can accelerate body (core temperature) cooling from 0.2 to 1.0 °C/10 min vs. control conditions, depending on the size/surface area of the extremity immersed. Arm immersion up to the elbow results in greater heat loss than hand- or foot-only immersion and may reduce cardiovascular strain by lowering heart rate by 10–25 beats/min and increase work tolerance time by up to 60%. The findings from studies in this paper support the use of AICS prototypes, which have been incorporated as part of the heat stress mitigation procedures employed in US Army Ranger Training and may have great application for sports and occupational use.  相似文献   

2.
Although limited almost exclusively to military trainees, acute respiratory disease (ARD) caused by adenovirus types 4 and 7 had been the leading cause of hospitalization in U.S. Army personnel. This decrease which resembles influenza in clinical manifestations led to hospitalization of as many as 50% of military trainees in midwinter and imposed a heavy burden on military hospitals and training programs. In studies undertaken from 1965 to 1970, live adenovirus type 4 and subsequently type 7 vaccines were found to be safe and immunogenic and to confer protection against type specific adenovirus ARD. For the past 5 yr. military trainees have been immunized with both adenovirus vaccines during periods of expected adenovirus disease. Since 1966, use of adenovirus vaccines has been monitored through the adenovirus surveillance program which yields weekly data on incidence and etiology of ARD in basic combat trainees. Since 1973, stable adenovirus vaccines have resulted in excellent control of adenovirus ARD. Potential problems with this immunization program are discussed.  相似文献   

3.
We investigated trends in biological control to both capture its evolution and explore future opportunities. We examined recent changes in public interest, international networking and peer-reviewed research. A Google Trends analysis revealed that the popularity of biological control is decreasing in terms of search hits on the internet. This trend is potentially worrying for the biological control community, given that public interest tends to drive political decisions regarding regulatory processes and governmental funding of research. To examine patterns of international collaboration, we established the list of authors who published their work in the three main biological control journals from the early 1990s to 2016. International co-authorship has intensified and the biological control sector is increasingly characterized by multilateral collaboration. We surveyed papers published in BioControl and Biological Control over the last 25 years to identify research trends with respect to target pests, commodities, biological control agents and biological control approaches. Finally, we report that articles on biological control are published in the broad-based scientific journals Science and Nature on a regular basis. This reflects contributions that biological control research makes to scientific discussions in general. Our analyses revealed a thriving scientific discipline with several major research trends in arthropod, plant pathogen and weed biological control.  相似文献   

4.
Abstract: Lactic acid has been an intermediate-volume specialty chemical (world production ∼ 40,000 tons/yr) used in a wide range of food processing and industrial applications. Lactic acid has the potential of becoming a very large volume, commodity-chemical intermediate produced from renewable carbohydrates for use as feedstocks for biodegradable polymers, oxygenated chemicals, plant growth regulators, environmentally friendly 'green' solvents, and specialty chemical intermediates. The recent announcements of new development-scale plants for producing lactic acid and polymer intermediates by major U.S. companies, such as Cargill, Ecochem (DuPont/ConAgra), and Archer Daniels Midland, attest to this potential.
In the past, efficient and economical technologies for the recovery and purification of lactic acid from crude fermentation broths and the conversion of lactic acid to the chemical or polymer intermediates had been the key technology impediments and main process cost centers. The development and deployment of novel separations technologies, such as electrodialysis (ED) with bipolar membranes, extractive distillations integrated with fermentation, and chemical conversion, can enable low-cost production with continuous processes in large-scale operations. The use of bipolar ED can virtually eliminate the salt or gypsum waste produced in the current lactic acid processes. Thus, the emerging technologies can use environmentally sound processes to produce environmentally useful products from lactic acid. The process economics of some of these processes and products can also be quite attractive. In this paper, the recent technical advances in lactic and polyactic acid processes are discussed. The economic potential and manufacturing cost estimates of several products and process options are presented. The technical accomplishments at Argonne National Laboratory (ANL) and the future directions of this program at ANL are discussed.  相似文献   

5.
Isoprene is facing a growing global market due to its wide industrial applications. Current industrial production of isoprene is almost entirely petroleum-based, which is influenced by the shrinking C5 supply, while the natural emission of isoprene is predominantly contributed by plants. To bridge the need gap, a highly efficient fermentation-based process for isoprene production might be a suitable and sustainable solution, and extensive research works have been performed to achieve this goal. Here we review the accomplishments in this field by summarizing the history and prospects of microbial isoprene production. The natural producers and biosynthesis pathways of isoprene, the key enzyme isoprene synthase and the metabolic engineering strategies adopted for developing isoprene-producing microorganisms are introduced. In particular, strategies employed for achieving engineered strains with improved performance indices are discussed based on the published papers and patents. The perspectives on further performance improvements and potential future strategies are presented as well.  相似文献   

6.
The need for batch-to-batch consistency in available dyes and stains used for biological purposes posed a considerable problem for United States scientists following World War I. Prior to that time, most of the acceptable stains in this country were of German origin. In an attempt to standardize the performance of biological stains and dyes, the Society of American Bacteriologists in 1922 appointed Dr. Harold Conn to form the Committee on the Standardization of Biological Stains. To assist him, Dr. Conn recruited scientists from several major professional scientific societies. Mr. Holland Will, a Rochester, NY, vendor of stains, was also instrumental in the Committee's success. This article traces the origin, mission and accomplishments of the product of that Committee, the Biological Stain Commission, through the past 75 years, and focuses on some of the major events that influenced and shaped its development.  相似文献   

7.
I McCulloch 《CMAJ》1995,153(10):1494-1497
Although Canada''s military physicians didn''t come to prominence until WW I and WW II, the Canadian Army Medical Corps (CAMC), the forerunner of the Royal Canadian Army Medical Corps and the current Canadian Forces Medical Service, actually had its origins in the Boer War. During that turn-of-the-century conflict, field hospitals accompanied Canadian troops to South Africa. Ian McCulloch discusses that early type of medical service and the steps that led to the creation of the CAMC.  相似文献   

8.
The need for batch-to-batch consistency in available dyes and stains used for biological purposes posed a considerable problem for United States scientists following World War I. Prior to that time, most of the acceptable stains in this country were of German origin. In an attempt to standardize the performance of biological stains and dyes, the Society of American Bacteriologists in 1922 appointed Dr. Harold Conn to form the Committee on the Standardization of Biological Stains. To assist him, Dr. Conn recruited scientists from several major professional scientific societies. Mr. Holland Will, a Rochester, NY, vendor of stains, was also instrumental in the Committee's success. This article traces the origin, mission and accomplishments of the product of that Committee, the Biological Stain Commission, through the past 75 years, and focuses on some of the major events that influenced and shaped its development.  相似文献   

9.
Between 1963 and 1970, the Smithsonian Institution held a grant from the US Army to observe migratory patterns of pelagic birds in the Central Pacific. For six years, the Pacific Ocean Biological Survey Program (POBSP) collected a vast amount of data from a quarter of the globe little known to science, and difficult for civilians to access. Its reports were (and remain) of great value to science. In 1969, however, the Program became embroiled in controversy. Some alleged that the Smithsonian, by accepting the military's coin, had violated its own rules governing the receipt of government funds and the publication of research. Recent investigations have pointed to a number of unexplained relationships between the POBSP and the Army, during a period of intense activity in chemical and biological weapons testing. The controversy marked a watershed in Smithsonian-military relations. As yet, its history is incomplete. What is known, however, suggests that the POBSP involved a highly problematic mésalliance between science and secrecy during the height of the Cold War. Its gradual unfolding prompts questions of contemporary relevance that await contemporary answers. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

10.
Water pollution control is presently one of the major thrust areas of scientific research. While coloured organic compounds generally impart only a minor fraction of the organic load to wastewaters, their colour renders them aesthetically unacceptable. Stringent regulating measures are coaxing industries to treat their waste effluents to increasingly high standards. Colour removal, in particular, has recently become an area of major scientific interest as indicated by the multitude of related research reports. During the past two decades, several decolourization techniques have been reported, few of which have been accepted by some industries. There is a need to find alternative treatments that are effective in removing dyes and colourants from large volume of effluents, which are cost-effective, like the biological or integrated systems. This article reviews some of the widely used and most promising industrial wastewater decolourization methods. Data on decolourizing efficiencies of different causative agents, obtained by means of different physical, chemical and biological methods are discussed. Further a critical review is made on the various treatment methodologies and emerging technologies with a note on their advantages and disadvantages.  相似文献   

11.
The risk assessment process is a critical function for deployment toxicology research. It is essential to the decision making process related to establishing risk reduction procedures and for formulating appropriate exposure levels to protect naval personnel from potentially hazardous chemicals in the military that could result in a reduction in readiness operations. These decisions must be based on quality data from well-planned laboratory animal studies that guide the judgements, which result in effective risk characterization and risk management. The process of risk assessment in deployment toxicology essentially uses the same principles as civilian risk assessment, but adds activities essential to the military mission, including intended and unintended exposure to chemicals and chemical mixtures. Risk assessment and Navy deployment toxicology data are integrated into a systematic and well-planned approach to the organization of scientific information. The purpose of this paper is to outline the analytical framework used to develop strategies to protect the health of deployed Navy forces.  相似文献   

12.
To delineate age- and gender-related differences in physiological responses to cold exposure, men and women between the ages of 20 and 29 yr and 51 and 72 yr, wearing minimal clothing, were exposed at rest for 2 h to 28, 20, 15, and 10 degrees C room temperatures with 40% relative humidity. During the coldest exposure, the rates of increase in metabolic rate (W X m-2 or ml X kg lean body mass-1 X min-1 were similar for all groups. However, older women (n = 7) may have benefited from a larger (P less than 0.05) early metabolic (M) increase (40% within 15 min) than young men (18%) (n = 10), young women (5%) (n = 10), or older men (5%) (n = 10). A similar rapid M response in older women occurred during the 15 degrees C exposure. During all cold exposures, older women maintained constant rectal temperature (Tre) and young women maintained Tre only during the 20 degrees C exposures, whereas Tre of the men declined during all cold exposures (P less than 0.01). Changes in Tre and mean skin temperature (Ts) during cold exposure were largely related to body fat, although age and surface area/mass modified the changes in men. The data suggest that older men are more susceptible to cold ambients than younger people, since they did not prevent a further decline in their initially relatively low Tre. Despite greater insulation from body fat, the older women maintained a constant Tre at greater metabolic cost than men or younger women.  相似文献   

13.
A biosensor is an analytical device that responds to an analyte in an appropriate sample and interprets its concentration as an electrical signal via a suitable combination of a biological recognition system and an electrochemical transducer. As a result of recent scientific and technological progress, such devices are likely to play an increasingly important role in generating analytical information in all sectors of human endeavour, from medicine to the military. In particular, biosensors will form the basis of cheap, simple devices for acquiring chemical information, bringing sophisticated analytical capabilities to the non-specialist and general public alike. The market opportunities for the rapid exploitation of novel developments in this sector are substantial. Biosensor research is also likely to have a significant impact on the development of modern electronics.  相似文献   

14.
长期以来, 分类学的研究成果主要以平面的方式发表在各种纸质文献资料中。近年来, 随着计算机和人工智能等新兴技术的发展和应用, 平面资料信息的数字化成为一种趋势, 世界各国都非常重视本国生物资源信息的收集汇总, 构建了多种数据库, 为科学研究、政府决策、资源保护、合理利用和科学传播提供了重要的信息基础。本研究探索并建立从菌物学平面资料信息构建数据库的流程和方法, 并在中国菌物名录数据库和Index Fungorum所收集数据的基础上进行数据挖掘和分析。通过软件操作和程序设计, 在数据库中提取相关信息, 辅助完成了《中国生物多样性红色名录——大型真菌卷》的编制工作, 同时梳理和规范了菌物拉丁和汉语学名, 为菌物分类研究和资源评估与保护提供基础。  相似文献   

15.
The review article covers three major aspects of scientific research on sediment-associated contaminants during the last 20 years: (i) identification and monitoring of sources and distribution (sampling; sample preparation; analyses, mainly of non-residual fractions; estimation of pollution potential); (ii) study of processes and mechanisms of pollutant transfer (interactions between dissolved and particulate element species; particle environments; transport and diagenesis: colloids; surface microlayers; particle related processes; bioturbation; dredging operations; remobilization of toxic elements; bioaccumulation of organic chemicals: solid/dissolved distribution of contaminants); (iii) assessment of the environmental impact of particle-bound pollutations (chemical extraction sequence; sediment bioassay; combined chemical/biological test procedures). Enstead, empirical tests developed from multi-disciplinary research on biological, chemical and physical factors are applied for assessing the reactivity, mobility and bioavailability of sediment-bound pollutations and for estimating the validity of remedial measures.  相似文献   

16.
During the past century, research studies using animal models have contributed to numerous scientific discoveries and have been vital for the understanding of numerous biological processes, including disease. Over the past decades, the scientific community has defined a small number of model organisms that includes a few mammals, fish (mainly zebrafish), birds (mainly chicken), frogs, flies, and nematodes. Rodents are by far the most commonly employed laboratory animals in biomedical research. Mice share many biological similarities to humans and can be genetically manipulated to express mutations linked to human diseases. Mice and rats reproduce relatively quickly and have a short life span, which allows scientists to study progressive disorders, including aging. A large range of inbred mice strains enables accurate and reproducible experiments by decreasing the variability often associated with animal models and biological systems in general. Finally, mice are cost‐effective, small, and relatively easy to handle, transport, and house. All of these advantages combine to make mice the major species for recapitulating and studying human diseases. However, focusing exclusively on one or very few animal models may lead researchers to lose sight of other species with vastly different biology that might inform and affect our understanding of disease pathogenesis.  相似文献   

17.
ABSTRACT: Copyright and licensing of scientific data, internationally, are complex and present legal barriers to data sharing, integration and reuse, and therefore restrict the most efficient transfer and discovery of scientific knowledge. Much data are included within scientific journal articles, their published tables, additional files (supplementary material) and reference lists. However, these data are usually published under licenses which are not appropriate for data. Creative Commons CC0 is an appropriate and increasingly accepted method for dedicating data to the public domain, to enable data reuse with the minimum of restrictions. BioMed Central is committed to working towards implementation of open data-compliant licensing in its publications. Here we detail a protocol for implementing a combined Creative Commons Attribution license (for copyrightable material) and Creative Commons CC0 waiver (for data) agreement for content published in peer-reviewed open access journals. We explain the differences between legal requirements for attribution in copyright, and cultural requirements in scholarship for giving individuals credit for their work through citation. We argue that publishing data in scientific journals under CC0 will have numerous benefits for individuals and society, and yet will have minimal implications for authors and minimal impact on current publishing and research workflows. We provide practical examples and definitions of data types, such as XML and tabular data, and specific secondary use cases for published data, including text mining, reproducible research, and open bibliography. We believe this proposed change to the current copyright and licensing structure in science publishing will help clarify what users -- people and machines -- of the published literature can do, legally, with journal articles and make research using the published literature more efficient. We further believe this model could be adopted across multiple publishers, and invite comment on this article from all stakeholders in scientific research.  相似文献   

18.
石质文物的生物风化问题普遍存在,随着全球气候与环境变化加剧,其面临的生物风化挑战日趋严峻,防风化任务愈趋紧迫.本文综述了地衣类微生物介导的石材风化机理及其与气候环境因子间的关系,讨论了地衣的生物保护作用和地衣防治中生物杀灭剂的效力评价,并展望了该领域未来的研究方向.对地衣-岩石界面的大量研究表明,生物风化可主要归因于以菌丝穿透和草酸钙形成为代表的生物物理风化和生物化学风化;露天石质文物的生物风化与包括石材基质、周边环境及气候因素等在内的整个生态系统多种非生物条件息息相关;地衣对石材兼具生物风化作用和生物保护效应.在石质文物风化修复方面,应逐步改善文物赋存的环境条件,建立用于生物风化和杀灭效率评估的行业规范和国家标准等“通用语言”,推进石质文物的科学保护.  相似文献   

19.
咖啡化学成分与健康   总被引:1,自引:0,他引:1  
咖啡数百年来一直作为功能饮料因而被称作第一饮品。咖啡的化学成分及其生物活性备受人们关注,本文仅对咖啡化学成分的特点及其一些主要成分的结构类型和生物活性、咖啡化学成分研究的新方法等进行了简要评论。  相似文献   

20.
Many biomedical experiments require the qualitative and quantitative localization of trace elements with high sensitivity and good spatial resolution. The feasibility of measuring the chemical form of the elements, the time course of trace element metabolism, and conducting experiments in living biological systems are also important requirements for biological trace element research. Nuclear analytical techniques that employ ion or photon beams have grown in importance in the past decade and have led to several new experimental approaches. Some of the important features of these methods are reviewed here along with their role in trace element research. Examples of their use are given to illustrate potential for new research directions. It is emphasized that the effective application of these methods necessitates a closely integrated multidisciplinary scientific team.  相似文献   

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