Impact of host community composition on Lyme disease risk

The drivers of variable disease risk in complex multi-host disease systems have proved very difficult to identify. Here we test a model that explains the entomological risk of Lyme disease (LD) in terms of host community composition. The model was parameterized in a continuous forest tract at the Cary Institute of Ecosystem Studies (formerly the Institute of Ecosystem Studies) in New York State, U.S.A. We report the results of continuing longitudinal observations (10 years) at the Cary Institute, and of a shorter-term study conducted in forest fragments in LD endemic areas of Connecticut, New Jersey, and New York, USA. Model predictions were significantly correlated with the observed nymphal infection prevalence (NIP) in both studies, although the relationship was stronger in the longer-term Cary Institute study. Species richness was negatively, albeit weakly, correlated with NIP (logistic regression), and there was no relationship between the Shannon diversity index (H') and NIP. Although these results suggest that LD risk is in fact dependent on host diversity, the relationship relies explicitly on the identities and frequencies of host species such that conventional uses of the term biodiversity (i.e., richness, evenness, H') are less appropriate than are metrics that include species identity. This underscores the importance of constructing interaction webs for vertebrates and exploring the direct and indirect effects of anthropogenic stressors on host community composition.     

Spawning and development in <Emphasis Type="Italic">Osedax</Emphasis> boneworms (Siboglinidae,Annelida)

We report observations on spawning and early development in bone-eating worms of the genus Osedax. Individual females of Osedax rubiplumus were observed at 1820 m depth freely spawning hundreds of oocytes, and females of an undescribed species, Osedax “orange collar”, were observed spawning in laboratory aquaria. Cytological and molecular analysis of the spawned oocytes of two Osedax species revealed no evidence for the bacterial endosymbionts that the female worms require for their nutrition, suggesting that the bacteria must be acquired later from the environment, as they are in other siboglinids. Individual O. “orange collar” females released an average of 335 (±130) eggs per day, but the number of oocytes spawned per day varied greatly, suggesting that not all the females spawned daily. Fertilization rates of the spawned oocytes varied from 0 to 100%, though most females showed nearly 100% fertilization rates. Oocytes spawned in the laboratory at 4–6°C were negatively buoyant. If fertilized, these oocytes extruded polar bodies and then after at least four hours cleaved unequally. Subsequent cleavages occurred in a spiral pattern at roughly 2-h intervals, resulting in free-swimming trochophore larvae after 24 h. These lecithotrophic trochophores swam for 9–16 days before settling with several hooked chaetae, similar to those of dwarf Osedax males. The larval life span of the Osedax species studied in the laboratory appears to be shorter than in closely related Vestimentifera. Osedax rubiplumus, on the other hand, has much larger oocytes and so may have greater dispersal potential than these other Osedax species. The high fecundity and apparently continuous reproduction of Osedax boneworms permits the opportunistic exploitation of sunken vertebrate bones. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

垃圾填埋气对植物生长影响初探

以11种上海常见绿化植物的盆栽幼苗为对象,在上海顾村垃圾填埋场就填埋气对这些植物幼苗生长和生理特征的影响进行了初步分析和比较。研究测定的形态指标和生理指标主要包括：生长势、存活率、株高变化、叶绿素含量和脯氨酸含量。结果表明：1）距离填埋气排放口越近的植物生长越差,存活率越低,株高变矮。2）距离填埋气排放口越近的植物叶绿素含量越小,脯氨酸含量越高。3）狗牙根（Cynodon dactylon）、构树（Broussonetia papyrifera）等植物出现了受害后的恢复性生长,暗示了其对垃圾填埋气良好的适应性,而蚊母树（Distylium racemosum）存活率低且生长势差,暗示了其对垃圾填埋气的极度不适应。本研究的结果可以为在高浓度填埋气环境下对垃圾填埋场进行近自然植被恢复提供一定的研究基础。     

城市绿地土壤呼吸时空变异及其影响因素

2012年7月-2012年12月,采用LI—COR-8100测定了柳树、圆柏和杏树3种北京绿化树木的土壤呼吸速率,并分析了生物因子和非生物因子对土壤呼吸的影响。结果表明：3个树种的土壤呼吸速率平均值为：柳树3．53μmol／（m2·s）,圆柏2．68μmol（m2·s）,杏树2．38μmol／（m2·s）;3种树木土壤呼吸速率呈现相似的月动态,与温度呈极显著指数相关,而与土壤水分相关性不显著。8月柳树和圆柏的土壤呼吸显著高于杏树;9月柳树的土壤呼吸显著高于圆柏和杏树;10—11月3种树木之间差异性不显著。8—9月土壤呼吸速率和温度、树木胸径、总碳、总氮、有机碳及硝态氮显著相关,而与碳氮比、叶面积指数呈极显著负相关。逐步回归分析表明,8—9月间3种树木的土壤呼吸主要受到树木胸径和叶面积指数的影响,模型解释率为42．0％（p=0．001）。     

SNAKES USED IN ETHNOMEDICINE IN NORTHEAST BRAZIL

This paper documents zootherapeutic practices in Northeast Brazil. It is primarily based on field surveys carried out in fishing villages located in the States of Maranhão and Paraíba, where dwellers provided information on snake species used as medicine, body parts used to prepare the remedies, and the illnesses to which the remedies were prescribed. The species used as medicinal drug and their respective families were: Crotalus durissus (rattlesnake), Bothrops leucurus (‘lance head’, a venomous snake), and Lachesis muta (bushmaster) of the family Crotalidae; and Boa constrictor (boa constrictor), Epicrates cenchria (‘salamanta’), and Eunectes murinus (anaconda) of the family (Boidae). These zootherapeutical resources were used for the cure of 14 illnesses. The most commonly cited species were Crotalus durissus (n=26) e Boa constrictor (n=6), Apparently, the medicinal use of snakes does not pose a threat for their population in the studied sites.     

基于关联向量机回归的水质预测模型

提出了一种基于关联向量机回归的水质时间序列预测模型,并以该模型对氢离子浓度指数(p H值)、溶解氧(DO)、高锰酸盐指数(CODMn)和氨氮(NH3-N)4种重要水质指标进行预测.首先采用国家环保部发布的四川攀枝花龙洞水质自动监测数据进行实验,对该模型的有效性进行了验证;然后将关联向量机回归预测模型与支持向量机回归预测模型进行比较.为了比较不同核函数的预测效果,实验中预测模型的核函数分别采用了线性函数和高斯函数.实验结果表明,关联向量机回归模型的预测效果不亚于支持向量机回归模型;且在给出预测值时,还能同时给出预测结果的可信程度.     

Marine Protected Area Design and the Spatial and Temporal Distribution of Cetaceans in a Submarine Canyon

Abstract: The Gully, the largest submarine canyon off the coast of eastern Canada, is currently under consideration as a marine conservation area, primarily because of the increasing interest in oil and gas production on the Scotian Shelf. Cetaceans, as a guild of abundant, large organisms that are relatively sensitive to such threats, provide a reliable means to determine the boundaries for a conservation area in this region. We compared the abundance of cetaceans between the Gully and other parts of the Scotian Shelf and Slope and found that abundance was higher in the Gully. We also assessed cetacean distribution and relative abundance within the Gully relative to search effort for several spatial and temporal parameters: depth, slope, sea surface temperature, and month. Distribution within the Gully was most strongly correlated with depth, but was also significantly correlated with sea surface temperature and month. Five of the 11 cetacean species commonly found in the Gully, and all those for which the Gully formed significant habitat on the Scotian Shelf, were concentrated in the deep (200–2000 m) mouth of the canyon. We suggest that a year-round marine protected area is necessary for the Gully. A core protection zone should be defined in the Gully based on depth and bounded by the 200-m isobath. A buffer zone around the core zone should be defined to provide protection from activities with further-reaching effects, such as noise, dredging, and chemical pollution.     

Implementing cash for work programmes in post-tsunami Aceh: experiences and lessons learned

Cash for work (CFW) programmes are utilised in various disaster and emergency contexts and were a prominent component of the tsunami response in Aceh province, Indonesia. This paper describes Mercy Corps' CFW programme, discusses CFW implementation experiences and provides key recommendations for similar programmes in future emergencies. For the majority of CFW participants and their households, CFW was the only source of household income and 93 per cent of household incomes were attributable to it. The CFW programme empowered displaced populations to return to their communities; 91 per cent of participants indicated that CFW facilitated their return. Other reported psychosocial benefits included providing productive activities and giving communities an opportunity to work together. Mercy Corps' experience in Aceh demonstrates that cash disbursements can be safely delivered in a widespread manner in emergencies, and that when implemented on a short-term basis, can have positive impacts at the individual and community level.     

Organizational practices and workplace health and safety: A cross-sectional study in manufacturing companies

We report the results of a mail questionnaire for 312 manufacturing firms in the province of Ontario (Canada). We conducted a cross-sectional analysis of workplace level health and safety policies, practices and attitudes. Analyses were conducted across firm categories based upon lost-time frequency rate (LTFR) data. Lower LTFRs were associated with paternalistic initiatives, recording of occupational health and safety (OHS) measures, greater involvement of workers in decision-making, and better managerial attitudes concerning the importance of OHS. The composition of the Joint Health and Safety Committee (JHSC), a committee mandated in all workplaces we sampled, differed according to injury rate: the mean number of worker (vs. management) members on the JHSC was higher for lower injury sites, and the mean number of worker members attending JHSC meetings was also higher for lower injury worksites. In addition, workplaces with lower LTFR benefitted by having JHSCs with more executive functions and greater worker involvement. In conclusion, managerial and worker participation in OHS initiatives characterizes safer workplaces. Also, general concern of management towards OHS—illustrated by both attitudes and concrete actions—is also associated with lower injury rates.