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71.
Primary lithium batteries contain hazardous materials such as lithium metal and flammable solvents, which can lead to exothermic activity and runaway reactions above a defined temperature. Lithium-ion batteries operating outside the safe envelope can also lead to formation of lithium metal and thermal runaway. Despite protection by battery safety mechanisms, fires originating from primary lithium and lithium-ion batteries are a relatively frequent occurrence.This paper reviews the hazards associated with primary lithium and lithium-ion cells, with an emphasis on the role played by chemistry at individual cell level. Safety mechanisms to prevent the occurrence and limit the consequences of incidents are reviewed, together with safety tests to monitor compliance with battery safety regulations and standards. Incident information from news accounts and open literature sources are reviewed to extract causal information.It is concluded that the potential severity of incidents during storage, transport and recycling of waste batteries can be significantly higher than in end-use applications. Safe storage, packaging and labelling practices, as well as communication among the parties involved, are essential to ensure safety across the battery lifecycle. It is recommended that a database of lithium battery incidents would be valuable to improve the evidence base for informing accident prevention measures.  相似文献   
72.
Rareness and specialization in plant-pollinator networks   总被引:1,自引:0,他引:1  
Most rare species appear to be specialists in plant-pollinator networks. This observation could result either from real ecological processes or from sampling artifacts. Several methods have been proposed to overcome these artifacts, but they have the limitation of being based on visitation data, causing interactions involving rare visitor species to remain undersampled. We propose the analysis of food composition in bee trap nests to assess the reliability of network specialization estimates. We compared data from a plant-pollinator network in the Monte Desert of Villavicencio Nature Reserve, Argentina, sampled by visit observation, and data from trap nests sampled at the same time and location. Our study shows that trap nest sampling was good for estimating rare species degree. The rare species in the networks appear to be more specialized than they really are, and the bias in the estimation of the species degree increases with the rareness. The low species degree of these rare species in the visitation networks results from insufficient sampling of the rare interactions, which could have important consequences for network structure.  相似文献   
73.
The depth distribution and temperature preferences of wahoo (Acanthocybium solandri) were quantified in the eastern North Pacific using archival tags. One hundred and eight data-loggers were deployed on wahoo (105?C165-cm fork length) from 2005 to 2008 at three locations off of the coast of Baja California Sur, Mexico (Alijos Rocks, 25°00??N/115°45??W; Magdalena Bay Ridge, 25°55??N/113°21??W; Hurricane Bank, 16°51??N/117°29??W). Twenty-five tagged individuals (23%) were recaptured within close proximity (<20?km) of their release sites. Collectively, depth and temperature data from 499?days revealed a predominant distribution within the upper mixed layer, with an average (±SD) depth of 18?±?4?m during the day and 17?±?6?m at night. Wahoo spent 99.2% of the daytime and 97.9% of night above the thermocline, and the greatest depth achieved by any fish was 253?m. Mean dive duration (3.8?±?2.9 vs. 2.3?±?0.8?min) and the vertical rate of movement (3.8?±?1.3 vs. 3.0?±?0.5?m?min?1) were greater at night when compared to day. Ambient temperatures obtained from tag records ranged from 11.1 to 27.9°C, with an average of 25.0?±?1.1°C. These data identify the importance of the warm, upper mixed layer for the wahoo. High recapture rates proximal to the deployment sites suggest seasonal site fidelity and reveal the economic importance of this resource to both commercial and recreational fisheries of the region.  相似文献   
74.
The protective effect of sodium bicarbonate (NaHCO3), a urine modifier, to alleviate murine ochratoxicosis was investigated. The study included two trials. Urinary pH was altered before oral administration of ochratoxin A (OA) in Trial 1, and animals were given combined doses of OA and ethyl biscoumacetate (Eb) in Trial 2. Acute toxicity of OA as measured by LD50 values was reduced by 23% and 20% in rats treated with NaHCO3 for Trials 1 and 2 respectively. Bicarbonate-treated rats dosed with 20 mg/kg OA or with a combination dose of OA at 17 mg/kg and Eb at 50 mg/kg, had a lower frequency of histological lesions in kidneys, liver, lung, spleen and heart. Two types of heart lesions found in the present study are described.  相似文献   
75.
BACKGROUND: The ability for suicides of drivers to be disguised as traffic accidents raises the possibility that suicidal behaviors of this nature are far more prevalent than previously thought, potentially impacting health, road safety, and insurance companies. METHOD: Persons residing at the Gold Coast, Australia, identified as having a history of suicidal ideation and behaviors (n = 1,196), were sent a mail-out survey after their consent was obtained in initial telephone contact (CATI random digit-dialing). Among those responding, 412 had made suicide plans or arrangements and 228 suicide attempts. RESULTS: Of those who reported planning a suicide, 14.8% (19.1% of male planners and 11.8% of female planners) had conceived to have a motor vehicle "accident" (n = 61). Of all attempters, 8.3% (13.3% of male attempters) had previously attempted via motor vehicle collision (n = 19). All attempters reported having emotional or mental problems at the time of the event. Suicide planners were significantly more likely to be in full-time employment and have a partner and children compared with other planners. CONCLUSION: The study gives a rare insight into driver suicide plans and attempts, via a large-scale community survey, to provide the best opportunity of collecting unbiased data on the driver suicide behavior. Results suggest the use of this method, particularly in attempts made by males, may be underreported leading to inaccuracy of statistics. The motives behind choosing this method are somewhat different to those behind other methods, including financial benefits and eliminating stigma in the aftermath of a suicide.  相似文献   
76.
The photolysis in water solution of three fungicides (Metalaxyl, Benalaxyl, and Furalaxyl) was studied under artificial light. At λ = 254 Benalaxyl and Furalaxyl underwent fast degradation with rearrangement reactions less complex than those of Metalaxyl. Under A = 254–290 the photolysis was very fast and Benalaxyl and Furalaxyl show a common behaviour. This was found to be a kinetic consecutive process leading, at first, to N‐2,6‐xylyl‐D,L‐alaninate (II), which was degraded to 2,6‐dimethylaniline (IV). This amine gives unknown products. Metalaxyl underwent a parallel/consecutive photodegradtion to give (II) and N‐(methoxyacetyl)‐2,6‐dimethylaniline (VI). While (II) was easily converted to (IV) as earlier, (VI) was more stable to photolysis. Under λ > 290 all the fungicides shown very slow degradation with pseudo first order rate constants. The photoproducts were degraded faster than the parent compounds by factors from 13 to 1800. The presence of photosensitizer in water (humic acids or acetone) resulted in total decomposition of fungicides and of their photoproducts.  相似文献   
77.
Feeding ecology of juvenile green turtles (Chelonia mydas) was studied from 2008 to 2011 at Samborombón Bay (35°30′–36°30′S, Argentina), combining data on digestive tract examination and stable isotope analysis through a Bayesian mixing model. We found that animal matter, in particular gelatinous plankton, was consumed in large proportions compared to herbivorous food items such as terrestrial plants and macroalgae. This diet is facilitated by the high abundance of gelatinous plankton in the region, thus confirming the adaptive foraging behaviour of the juveniles according to prey abundance in the SW Atlantic. To our knowledge, this is the first study to employ this combination of techniques and to conclusively demonstrate that animal matter, in particular gelatinous plankton, is important in the diet of the neritic green sea turtles.  相似文献   
78.
Adaptive strategies of sex allocation functioning to increase fitness, including strategic allocation of sex in relation to birth order and sex composition of the progeny, have frequently been explored, but the development of a statistical framework for these analyses has lagged behind. In this paper, we contribute to filling this gap by devising a method for analyzing sex sequences based on a proper parameterization of generalized linear mixed models (GLMMs). The method is highly flexible and can be easily extended to investigate sequences of traits or events or other longitudinal data. As a worked example, we focus on the analysis of sex sequences of offspring produced by females in a single reproductive event and develop a method that allows analyzing simultaneously sequences of different length (e.g., clutches of different size) and sequences with missing data, as may frequently happen in “real-world” data sets. Different patterns of allocation among traits or events along the sequence were investigated, and a real data base of sex sequences of eclectus parrots (Eclectus roratus) fledglings produced by different females was analyzed. A tutorial for running the analyses with the R or the SAS software is provided in the Electronic Supplementary Material.  相似文献   
79.
Assessing the sustainability of complex development processes requires multi-causal and integrated analyses. We develop a system-based methodology, rooted in interdisciplinary discussion and consensus building between 15 experts, to construct a multi-causal diagram which examines the sustainability of the Argentine Pampas′ process of agriculturization. The resulting diagram includes 25 factors and provides a big-picture of the multiple dimensions and interrelations affecting sustainability. According to this examination, the increasing concentration of production and the incorporation of technological innovations, triggered by economic and institutional factors, are the cause of environmental distresses and social changes, whose consequences for sustainability are still highly disputed. Nevertheless, the symptoms of both environmental and social unsustainability are more evident in the case of the extra-Pampean regions than in the Pampas. This suggests that the Pampean agriculture model should not be transferred to these regions without substantial modifications. The experts did not reach consensus on whether the agriculturization process is overall sustainable or unsustainable. Lack of consensus revolved mainly around opposing perspectives regarding the significance of the threats to environmental sustainability. The magnitude of socio-distributive unbalance and loss of rural jobs were also contentious. Yet, the paper shows how the exercise of building a joint causal diagram was undoubtedly helpful for linking piece-meal disciplinary facts, brought in from all fronts, into a comprehensive and coherent picture. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
80.
The recognition that growing proportions of species worldwide are endangered has led to the development of comparative analyses to elucidate why some species are more prone to extinction than others. Understanding factors and patterns of species vulnerability might provide an opportunity to develop proactive conservation strategies. Such comparative analyses are of special concern at national scales because this is the scale at which most conservation initiatives take place. We applied powerful ensemble learning models to test for biological correlates of the risk of decline among the Bolivian mammals to understand species vulnerability at a national scale and to predict the population trend for poorly known species. Risk of decline was nonrandomly distributed: higher proportions of large‐sized taxa were under decline, whereas small‐sized taxa were less vulnerable. Body mass, mode of life (i.e., aquatic, terrestrial, volant), geographic range size, litter size, home range, niche specialization, and reproductive potential were strongly associated with species vulnerability. Moreover, we found interacting and nonlinear effects of key traits on the risk of decline of mammals at a national scale. Our model predicted 35 data‐deficient species in decline on the basis of their biological vulnerability, which should receive more attention in order to prevent their decline. Our results highlight the relevance of comparative analysis at relatively narrow geographical scales, reveal previously unknown factors related to species vulnerability, and offer species‐by‐species outcomes that can be used to identify targets for conservation, especially for insufficiently known species. Predección y Definición de Prioridades de Conservación para Mamíferos de Bolivia con Base en Correlaciones Biológicas del Riesgo de Declinación  相似文献   
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