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71.
Female mate choice has been shown to provide direct mating benefits in several animal groups. In butterflies, for which there are increasing reports of fine-scale color-based mate choice, the evolutionary benefits that accrue from such mating biases, if any, are largely unknown. We addressed this issue in the butterfly Colias eurytheme, a species in which females choose mates on the basis of iridescent ultraviolet (UV) wing ornamentation and in which males donate reproductively beneficial nuptial gifts. In the first experiment, we assessed the mass of gifts donated to 77 virgin females by males sampled directly from a field encounter site. Despite large variance in the male adult phenotype and ejaculate, no single aspect of dorsal wing coloration, including UV brightness, chroma, or hue, was related to ejaculate mass. There was, however, an interesting interaction between the effects of male body size and copula duration upon ejaculate mass, with size scaling positively with ejaculate mass among males involved in shorter copulations (those lasting <70 min) but negatively among males in longer copulations. In the second experiment, we assessed the lifetime fecundity, fertility, and longevity of 85 females mated under similar circumstances to free-flying wild males. Although several wing color parameters proved subtly informative in more sophisticated multivariable models, no model predicted more than about 20% of the variation in any single female fitness parameter. The duration of copulation, which ranged from 35 min to over 16 h and which carries putative costs for females, was, again, only very weakly predicted by male wing color parameters (i.e., R 2 = 0.089). Given the overall minor predictive power of male wing coloration in general and of UV brightness in particular, our results do not strongly support the hypothesis that female C. eurytheme prefer bright UV males to obtain direct benefits or to minimize the costs associated with lengthy copulations.  相似文献   
72.
The efficacy of protected areas varies, partly because socioeconomic factors are not sufficiently considered in planning and management. Although integrating socioeconomic factors into systematic conservation planning is increasingly advocated, research is needed to progress from recognition of these factors to incorporating them effectively in spatial prioritization of protected areas. We evaluated 2 key aspects of incorporating socioeconomic factors into spatial prioritization: treatment of socioeconomic factors as costs or objectives and treatment of stakeholders as a single group or multiple groups. Using as a case study the design of a system of no‐take marine protected areas (MPAs) in Kubulau, Fiji, we assessed how these aspects affected the configuration of no‐take MPAs in terms of trade‐offs between biodiversity objectives, fisheries objectives, and equity in catch losses among fisher stakeholder groups. The achievement of fisheries objectives and equity tended to trade‐off concavely with increasing biodiversity objectives, indicating that it is possible to achieve low to mid‐range biodiversity objectives with relatively small losses to fisheries and equity. Importantly, the extent of trade‐offs depended on the method used to incorporate socioeconomic data and was least severe when objectives were set for each fisher stakeholder group explicitly. We found that using different methods to incorporate socioeconomic factors that require similar data and expertise can result in plans with very different impacts on local stakeholders.  相似文献   
73.
Improvements in human wellbeing are dependent on improving ecosystems. Such considerations are particularly pertinent for regions of high ecological, but also social and cultural importance that are facing rapid change. One such region is the Great Barrier Reef (GBR). Although the GBR has world heritage status for its ‘outstanding universal value’, little is known about resident perceptions of its values. We surveyed 1545 residents, finding that absence of visible rubbish; healthy reef fish, coral cover, and mangroves; and iconic marine species, are considered to be more important to quality of life than the jobs and incomes associated with industry (most respondents were dissatisfied with the benefits they received from industry). Highly educated females placed more importance on environmental non-use values than other respondents; less educated males and those employed in mining found non-market use-values relatively more important. Environmental non-use values emerged as the most important management priority for all.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0554-3) contains supplementary material, which is available to authorized users.  相似文献   
74.
The meaning of hydraulic fracturing for shale gas is contested worldwide: is it an energy game changer, a transition fuel, or a technology that poses severe environmental problems? In the Netherlands, a policy controversy developed in which fracturing was reframed from ‘business as usual’ to a potential environmental risk. This article theoretically and empirically describes this shift by arguing that the technology of hydraulic fracturing for shale gas is a boundary object that created a sphere of engagement for all sorts of actors. In this sphere, they negotiated a common but soft meaning of this technology. These negotiations consisted of frame contests. As part of those contests, the discursive strategies of framing and boundary work enabled opponents to create uncertainty about economic benefits and environmental impact. The shift in meaning transformed the issue from an economic one with standard governmental rules and regulations into a planning issue that needs more precaution.  相似文献   
75.
Sustainability science aims to help societies across the globe address the increased environmental and health crises and risks that range from poverty to climate change to health pandemics. With the increased magnitude and frequency of these large-scale risks to different societies, scientists and institutions have increasingly recognized the need for improved communication and collaboration among researchers, governments, businesses, and communities. This article argues that risk communication has fundamentally important contributions to make to sustainability science’s mission to create use-inspired, “actionable science” that can lead to solutions. Risk communication research can advance the mission of sustainability science to engage a wide range of stakeholders. This kind of engagement is especially important in the context of addressing sustainability problems that are characterized by high levels of uncertainty and complexity. We introduce three core tenets of risk communication research that are fundamental to advancing sustainability science. Risk communication specifically offers an increased understanding of how system feedbacks, human perceptions, and levels of uncertainty influence the study and design of solutions within social ecological systems.  相似文献   
76.
In recent years, animal welfare has become an important element of sustainable production that has evolved along with the transformation of animal production systems. Consumer attitudes towards farm animal welfare are changing around the world, especially at emerging markets of Asia, Africa and Latin America. Survey-based research on consumer attitudes towards farm animal welfare has increased. However, the geographical coverage of studies on consumer attitudes and perceptions about farm animal welfare has mostly been limited to Europe, and North America. Until now, Latin American consumers’ attitudes towards animal welfare have not been well studied. Despite the fact that Mexico, Chile and Brazil belong to the same region (according to international organizations), there are marked differences between these countries in terms of their economical and geographical characteristics among other factors. Those differences potentially have an impact on consumer attitudes towards animal welfare and livestock production systems in general. Given the evidence from the literature review, it seems advisable that Latin American producers and food industry who engage in animal welfare-enhancing practices should clearly label their products with information on the type of husbandry system to reach those consumers who want to make an informed choice. Therefore, there are some aspects that need to be studied and cannot be worked separately in order to promote and understand consumer attitudes towards dairy and beef systems, such as geography, economic development, and politics.  相似文献   
77.

Objectives

To evaluate the clinical significance of nuchal translucency (NT) between the 95th–99th percentile in terms of typical and atypical chromosomal abnormalities (ACAs), associated fetal congenital defects and postnatal outcome.

Methods

A retrospective cohort study of fetuses with NT between the 95th–99th percentile. Data regarding the rate of associated fetal defects, genetic abnormalities and postnatal outcome were collected.

Results

A total of 306 cases of fetuses with an NT between the 95th–99th percentiles were included. The overall rate of genetic abnormalities was 12.1% (37/306). Chromosomal abnormalities were found in 10.1% (31/306) of cases and 2% were ACA (6/306). Within this group, two were pathogenic Copy Number Variants (CNVs) and four were single gene disorders. The overall rate of fetal congenital defects was 13.7% (42/306). All ACAs were found in fetuses with congenital defects. Postnatally, a new diagnosis of a single gene disorder was made in 0.85% of cases (2/236).

Conclusions

The presence of an NT between the 95th–99th percentiles carries a 10-fold increased risk of fetal defects, representing an indication for referral for a detailed fetal anatomy evaluation. The risk of ACA is mainly related to the presence of fetal defects, irrespective of the combined test risk.  相似文献   
78.
Associations were examined between riparian canopy cover, presence of cattle near streams, and month of year with the concentration of Enterococcus (Most Probable Number (MPN)/100 ml) in surface water at Waipā watershed on the North Side of the Hawaiian island Kaua'i. Each one percent decrease in riparian canopy cover was associated with a 3.6 MPN/100 ml increase of waterborne Enterococcus. Presence of cattle near monitoring sites was associated with an increase of 99.3 MPN/100 ml of Enterococcus in individual grab samples. Lastly, summer samples (July) were substantially higher in concentration of Enterococcus than winter collected samples (February) in Enterococcus in sampled streams. These results suggest that reducing canopy cover and introduction of cattle into riparian zones may contribute to increases of Enterococcus concentrations in stream water.  相似文献   
79.

Purpose

We reviewed 19 studies of mammals fed with commercialized genetically modified soybean and maize which represent, per trait and plant, more than 80% of all environmental genetically modified organisms (GMOs) cultivated on a large scale, after they were modified to tolerate or produce a pesticide. We have also obtained the raw data of 90-day-long rat tests following court actions or official requests. The data obtained include biochemical blood and urine parameters of mammals eating GMOs with numerous organ weights and histopathology findings.

Methods

We have thoroughly reviewed these tests from a statistical and a biological point of view. Some of these tests used controversial protocols which are discussed and statistically significant results that were considered as not being biologically meaningful by regulatory authorities, thus raising the question of their interpretations.

Results

Several convergent data appear to indicate liver and kidney problems as end points of GMO diet effects in the above-mentioned experiments. This was confirmed by our meta-analysis of all the in vivo studies published, which revealed that the kidneys were particularly affected, concentrating 43.5% of all disrupted parameters in males, whereas the liver was more specifically disrupted in females (30.8% of all disrupted parameters).

Conclusions

The 90-day-long tests are insufficient to evaluate chronic toxicity, and the signs highlighted in the kidneys and livers could be the onset of chronic diseases. However, no minimal length for the tests is yet obligatory for any of the GMOs cultivated on a large scale, and this is socially unacceptable in terms of consumer health protection. We are suggesting that the studies should be improved and prolonged, as well as being made compulsory, and that the sexual hormones should be assessed too, and moreover, reproductive and multigenerational studies ought to be conducted too.  相似文献   
80.
Objective: Whiplash research has largely focused on rear collisions because they account for the majority of whiplash injuries. The purpose of this study was to evaluate the effects of 4 perturbation directions (anterior, posterior, right, and left) on muscle activity and head kinematics to provide insight into the whiplash mechanism of injury. Methods: The effects of 4 perturbation directions induced by a parallel robotic platform, with peak acceleration of 8.50?m/s(2), were analyzed on 10 subjects. Surface electromyography (EMG) measures were collected from the sternocleidomastoid (SCM), trapezius, and splenius capitus muscles. Kinematics of the head, thorax, and head relative to thorax were also measured. Results: We observed stereotypic responses for kinematics and SCM EMG for the various perturbation directions; the trapezius and splenius capitus muscles showed amplitudes that were less than 5 percent maximum voluntary contraction (MVC). Rear perturbations elicited the smallest onset latencies for the SCM (30?ms) and kinematic variables and greatest linear head center of mass (COM) accelerations. Frontal perturbations resulted in an average SCM onset latency of 143?ms and demonstrated the greatest magnitude of head translations and rotations relative to the thorax. Left and right perturbations demonstrated similar kinematics and SCM onset latencies (55 and 65?ms, respectively). Conclusions: Compared to frontal, left, and right directions, rear perturbations showed smaller SCM onset latencies, greater SCM amplitudes, and larger head accelerations, relating to a greater potential for injury. We suggest that the greater contact area and stiffness of the seatback, in the posterior direction, compared to restrictions in other directions, led to increased peak head accelerations and shorter SCM onset latencies.  相似文献   
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