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101.
Wild animals eating agricultural products and coming close to people's residences are primary causes of human–wildlife conflict worldwide. When carnivores eat anthropogenic foods and cause human safety concerns, it often results in the removal of the animals and public demand for reduced wildlife populations. The use of remote methods, such as scare devices, to deter carnivores has been touted in the literature; however, efficacy evidence remains thin. I test the efficacy of a widely available motion-activated solar alarm lamp to deter grizzly bears (Ursus arctos) from farms in Montana, USA. When scare devices were activated, there was a 46% reduction in the odds bears would access an attractant. For every additional scare device, there was an additional 44% reduction in the odds of a bear getting the food. Additionally, scare devices caused bears to be more vigilant and increase movement behavior. More bears in a group led to loss of deterrence efficacy, and there was no evidence for habituation to the aversive stimuli. This deterrence method was most effective in August and for fungicide-treated wheat. Out of 21 farms, scare devices stopped bears from returning to 11 sites. Overall, scare devices can be a cheap and easy first step to preventing, or resolving, some grizzly bear issues in the use-of-force continuum, which hierarchically organizes conflict responses from non-lethal to more severe.  相似文献   
102.
Synthetic biology includes an effort to logically control cellular behavior. One long-term goal is to implement medical interventions inside living cells, creating intracellular "disease fighters"; one may imagine a system that detects viral infection and responds to halt the spread of the virus. Here, we explore a system designed to display some of the qualitative features that such disease prevention systems should have, while not claiming that the system itself has any medical application. An intracellular disease prevention mechanism should: lie dormant in the absence of the disease state; detect the onset of a lethal disease pathway; respond to halt or mitigate the disease's effects; and be subject to external deactivation when required. We have created a device that displays these properties, in the highly simplified case of a bacterial viral disease. Our system detects the onset of the lytic phase of bacteriophage lambda in Escherichia coli, responds by preventing this lethal pathway from being followed, and is deactivated by a temperature shift. We have formulated a mathematical model of the engineered system, using parameters obtained from the literature and by local experimental measurement, and shown that the model captures the essential experimental behavior of the system in most parameter regimes.  相似文献   
103.
Cancer is one of the most deadly diseases in the world. Although advances in the field of chemo-preventive and therapeutic medicine have been made regularly over the last ten years, the search for novel anticancer treatments continues. In this field, the marine environment, with its rich variety of organisms, is a largely untapped source of novel compounds with potent antitumor activity. Although many reviews of marine anticancer compounds have been published, we focus here on selected marine compounds that act on the six hallmarks of cancer presented namely self-sufficiency in growth signals, insensitivity to anti-growth signals, evasion of apoptosis, limitless replication, sustained angiogenesis and tissue invasion and metastasis.  相似文献   
104.
Phenylethanoid glycosides are naturally occurring water-soluble compounds with remarkable biological properties that are widely distributed in the plant kingdom. Verbascoside is a phenylethanoid glycoside that was first isolated from mullein but is also found in several other plant species. It has also been produced by in vitro plant culture systems, including genetically transformed roots (so-called ‘hairy roots’). Verbascoside is hydrophilic in nature and possesses pharmacologically beneficial activities for human health, including antioxidant, anti-inflammatory and antineoplastic properties in addition to numerous wound-healing and neuroprotective properties. Recent advances with regard to the distribution, (bio)synthesis and bioproduction of verbascoside are summarised in this review. We also discuss its prominent pharmacological properties and outline future perspectives for its potential application.  相似文献   
105.
Electron transfer (ET) reactions are important for their implications in both oxidative and reductive DNA damages. The current contribution investigates the efficacy of caffeine, a xanthine alkaloid in preventing UVA radiation induced ET from a carcinogen, benzo[a]pyrene (BP) to DNA by forming stable caffeine–BP complexes. While steady‐state emission and absorption results emphasize the role of caffeine in hosting BP in aqueous medium, the molecular modeling studies propose the energetically favorable structure of caffeine–BP complex. The picosecond‐resolved emission spectroscopic studies precisely explore the caffeine‐mediated inhibition of ET from BP to DNA under UVA radiation. The potential therapeutic activity of caffeine in preventing DNA damage has been ensured by agarose gel electrophoresis. Furthermore, time‐gated fluorescence microscopy has been used to monitor caffeine‐mediated exclusion of BP from various cell lines including squamous epithelial cells, WI‐38 (fibroblast), MCF‐7 (breast cancer) and HeLa (cervical cancer) cells. Our in vitro and ex vivo experimental results provide imperative evidences about the role of caffeine in modified biomolecular recognition of a model carcinogen BP by DNA resulting dissociation of the carcinogen from various cell lines, implicating its potential medicinal applications in the prevention of other toxic organic molecule induced cellular damages. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
106.
布鲁氏菌病(简称布病)是由布鲁氏菌属细菌侵入机体引起的人畜共患传染病.近年来,布病疫情在世界范围内呈反弹趋势,我国尤甚.进入2000年以后,人间布病在我国成为报告发病数上升速度最快的传染病之一,令我国布病防治形势严峻.为了明确我国布病防治工作的现状和需求、最新研究现状和研究动态以及面临的挑战和机遇,深入研讨分析我国布病防治研究中的重大科学和关键技术问题,凝练和提出今后我国布病防治研究发展中亟需关注、解决的重要基础科学问题,在国家自然科学基金委员会资助下,由中国疾病预防控制中心地方病控制中心主办,哈尔滨医科大学、中国疾病预防控制中心传染病预防控制所和内蒙古地方病防治研究中心共同协办,于2013年6月21日召开了由来自全国布病防治与基础研究领域专家共同参加的“布鲁氏菌病防治基础研究发展战略研讨会”.会议在我国布病疫情最重的省份内蒙古自治区呼和浩特市召开,中国疾病预防控制中心传染病预防控制所、军事医学科学院疾病预防控制所、石河子大学、中国兽医药品监察所等19家从事布病防治与基础研究的科研院所、高等院校、疾病防治机构的40余位专家参加了此次会议.现结合文献资料以及本次会议的内容,对国内外布病流行现状、研究进展,以及影响我国布病防治的亟需解决的科学问题和建议作一综述.  相似文献   
107.
Frank B. Hu 《Aging cell》2014,13(3):391-400
Excess body weight and adiposity cause insulin resistance, inflammation, and numerous other alterations in metabolic and hormonal factors that promote atherosclerosis, tumorigenesis, neurodegeneration, and aging. Studies in both animals and humans have demonstrated a beneficial role of dietary restriction and leanness in promoting health and longevity. Epidemiological studies have found strong direct associations between increasing body mass index (BMI) and risks of developing type 2 diabetes, cardiovascular disease, and several types of cancer, beginning from BMI of 20–21 kg m−2. Although a recent meta-analysis suggests that overweight individuals have significantly lower overall mortality than normal-weight individuals, these data are likely to be an artifact produced by serious methodological problems, especially confounding by smoking, reverse causation due to existing chronic disease, and nonspecific loss of lean mass and function in the frail elderly. From a clinical and public health point of view, maintaining a healthy weight through diet and physical activity should remain the cornerstone in the prevention of chronic diseases and the promotion of healthy aging.  相似文献   
108.
109.
Dynamic gait stability can be quantified by the relationship of the motion state (i.e. the position and velocity) between the body center of mass (COM) and its base of support (BOS). Humans learn how to adaptively control stability by regulating the absolute COM motion state (i.e. its position and velocity) and/or by controlling the BOS (through stepping) in a predictable manner, or by doing both simultaneously following an external perturbation that disrupts their regular relationship. Post repeated-slip perturbation training, for instance, older adults learned to forward shift their COM position while walking with a reduced step length, hence reduced their likelihood of slip-induced falls. How and to what extent each individual joint influences such adaptive alterations is mostly unknown. A three-dimensional individualized human kinematic model was established. Based on the human model, sensitivity analysis was used to systematically quantify the influence of each lower limb joint on the COM position relative to the BOS and the step length during gait. It was found that the leading foot had the greatest effect on regulating the COM position relative to the BOS; and both hips bear the most influence on the step length. These findings could guide cost-effective but efficient fall-reduction training paradigm among older population.  相似文献   
110.
Approximately 320,000 anterior cruciate ligament (ACL) injuries in the United States each year are non-contact injuries, with many occurring during a single-leg jump landing. To reduce ACL injury risk, one option is to improve muscle strength and/or the activation of muscles crossing the knee under elevated external loading. This study?s purpose was to characterize the relative force production of the muscles supporting the knee during the weight-acceptance (WA) phase of single-leg jump landing and investigate the gastrocnemii forces compared to the hamstrings forces. Amateur male Western Australian Rules Football players completed a single-leg jump landing protocol and six participants were randomly chosen for further modeling and simulation. A three-dimensional, 14-segment, 37 degree-of-freedom, 92 muscle-tendon actuated model was created for each participant in OpenSim. Computed muscle control was used to generate 12 muscle-driven simulations, 2 trials per participant, of the WA phase of single-leg jump landing. A one-way ANOVA and Tukey post-hoc analysis showed both the quadriceps and gastrocnemii muscle force estimates were significantly greater than the hamstrings (p<0.001). Elevated gastrocnemii forces corresponded with increased joint compression and lower ACL forces. The elevated quadriceps and gastrocnemii forces during landing may represent a generalized muscle strategy to increase knee joint stiffness, protecting the knee and ACL from external knee loading and injury risk. These results contribute to our understanding of how muscle?s function during single-leg jump landing and should serve as the foundation for novel muscle-targeted training intervention programs aimed to reduce ACL injuries in sport.  相似文献   
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