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181.
Elizabeth A. Law Nathan J. Bennett Christopher D. Ives Rachel Friedman Katrina J. Davis Carla Archibald Kerrie A. Wilson 《Conservation biology》2018,32(2):294-303
Conservation decisions increasingly involve multiple environmental and social objectives, which result in complex decision contexts with high potential for trade‐offs. Improving social equity is one such objective that is often considered an enabler of successful outcomes and a virtuous ideal in itself. Despite its idealized importance in conservation policy, social equity is often highly simplified or ill‐defined and is applied uncritically. What constitutes equitable outcomes and processes is highly normative and subject to ethical deliberation. Different ethical frameworks may lead to different conceptions of equity through alternative perspectives of what is good or right. This can lead to different and potentially conflicting equity objectives in practice. We promote a more transparent, nuanced, and pluralistic conceptualization of equity in conservation decision making that particularly recognizes where multidimensional equity objectives may conflict. To help identify and mitigate ethical conflicts and avoid cases of good intentions producing bad outcomes, we encourage a more analytical incorporation of equity into conservation decision making particularly during mechanistic integration of equity objectives. We recommend that in conservation planning motivations and objectives for equity be made explicit within the problem context, methods used to incorporate equity objectives be applied with respect to stated objectives, and, should objectives dictate, evaluation of equity outcomes and adaptation of strategies be employed during policy implementation. 相似文献
182.
Plants are expected to differentially allocate resources to reproduction, growth, and survival in order to maximize overall fitness. Life history theory predicts that the allocation of resources to reproduction should occur at the expense of vegetative growth. Although it is known that both organism size and resource availability can influence life history traits, few studies have addressed how size dependencies of growth and reproduction and variation in resource supply jointly affect the coupling between growth and reproduction. In order to understand the relationship between growth and reproduction in the context of resource variability, we utilize a long-term observational data set consisting of 670 individual trees over a 10-year period within a local population of Bursera simaruba (L.) Sarg. We (1) quantify the functional form and variability in the growth-reproduction relationship at the population and individual-tree level and (2) develop a theoretical framework to understand the allometric dependence of growth and reproduction. Our findings suggest that the differential responses of allometric growth and reproduction to resource availability, both between years and between microsites, underlie the apparent relationship between growth and reproduction. Finally, we offer an alternative approach for quantifying the relationship between growth and reproduction that accounts for variation in allometries. 相似文献
183.
The electrosensory capabilities of wobbegong sharks are of particular interest, partly because very little is known about
their behavioural ecology and specifically because of their unusual ambush predatory strategy and benthic lifestyle. While
several biological functions of electroreception have been proposed, less consideration has been given to the functional significance
of interspecific differences in the morphology and topographic distribution of the ampullary organs. The morphology of the
ampullary organs was examined in four species of wobbegong shark, and the distribution of electroreceptive pores was mapped
in two species. The ampullary systems of wobbegongs are similar in morphology to other marine elasmobranchs. The number of
alveoli per ampullae is not significantly different between the four species; however, differences are seen between ampullary
cell size in some species. Ampullary pore distribution patterns are relatively unique, with the majority of pores occurring
on the dorsal region of the head. Wobbegongs feed primarily on demersal teleost fishes, and as the benthic and well-camouflaged
wobbegong remains motionless, these fish could be easily detected by the dorsal pores when swimming within range. 相似文献
184.
The people of the Democratic Republic of Congo for decades have been living in a situation of chronic crisis. Violence, population displacement and the destruction of infrastructure and health services have devastated the health of the population. In 2001, Médicins Sans Frontières conducted a survey in five areas of western and central DRC to assess mortality, access to health-care, vaccination coverage and exposure to violence. High mortality rates were found in front-line zones, mainly due to malnutrition and infectious diseases. In Basankusu approximately 10 per cent of the total population and 25 per cent of the under-five population had perished in the year before the survey. Humanitarian needs remain acute across the country, particularly near the front line. Infectious-disease control and treatment are a priority, as is increasing access to health-care. Humanitarian assistance must be increased considerably, especially in rural areas and zones that have been affected directly by conflict. 相似文献
185.
Sharks are apex predators, and their evolutionary success is in part due to an impressive array of sensory systems, including
vision. The eyes of sharks are well developed and function over a wide range of light levels. However, whilst close relatives
of the sharks—the rays and chimaeras—are known to have the potential for colour vision, an evolutionary trait thought to provide
distinct survival advantages, evidence for colour vision in sharks remains equivocal. Using single-receptor microspectrophotometry,
we measured the absorbance spectra of visual pigments located in the retinal photoreceptors of 17 species of shark. We show
that, while the spectral tuning of the rod (wavelength of maximum absorbance, λmax 484–518 nm) and cone (λmax 532–561 nm) visual pigments varies between species, each shark has only a single long-wavelength-sensitive cone type. This
suggests that sharks may be cone monochromats and, therefore, potentially colour blind. Whilst cone monochromacy on land is
rare, it may be a common strategy in the marine environment: many aquatic mammals (whales, dolphins and seals) also possess
only a single, green-sensitive cone type. It appears that both sharks and marine mammals may have arrived at the same visual
design by convergent evolution. The spectral tuning of the rod and cone pigments of sharks is also discussed in relation to
their visual ecology. 相似文献
186.
The problem of scale dependency is widespread in investigations of ecological communities. Null model investigations of community assembly exemplify the challenges involved because they typically include subjectively defined "regional species pools." The burgeoning field of community phylogenetics appears poised to face similar challenges. Our objective is to quantify the scope of the problem of scale dependency by comparing the phylogenetic structure of assemblages across contrasting geographic and taxonomic scales. We conduct phylogenetic analyses on communities within three tropical forests, and perform a sensitivity analysis with respect to two scaleable inputs: taxonomy and species pool size. We show that (1) estimates of phylogenetic overdispersion within local assemblages depend strongly on the taxonomic makeup of the local assemblage and (2) comparing the phylogenetic structure of a local assemblage to a species pool drawn from increasingly larger geographic scales results in an increased signal of phylogenetic clustering. We argue that, rather than posing a problem, "scale sensitivities" are likely to reveal general patterns of diversity that could help identify critical scales at which local or regional influences gain primacy for the structuring of communities. In this way, community phylogenetics promises to fill an important gap in community ecology and biogeography research. 相似文献
187.
Concentrations of polychlorinated biphenyls (PCBs) in water, sediment, and aquatic biota in the Houston Ship Channel, Texas 总被引:14,自引:0,他引:14
Polychlorinated biphenyls (PCBs) were quantified in water, sediment, and catfish and crab tissue collected from the Houston Ship Channel (HSC) in Texas. The total concentrations of the 209 PCB congeners ranged from 0.49 to 12.49 ng l(-1), 4.18 to 4601 ng g(-1) dry wt, 4.13 to 1596 ng g(-1) wet wt, and 3.44 to 169 ng g(-1) wet wt, in water, sediment, catfish and crab tissue, respectively. All media showed maximum concentrations greater than studies in other regions with the highest concentrations occurring in the most industrialized segments of the channel. Inter-media correlations suggested that sediment is a source to water. Galveston Bay sediment concentrations compared to a previous study showed a declining trend though the rate of the decline may be slowing. Detailed homolog profiles revealed that the industrialized part of the channel may be receiving PCB-laden sediment from its tributaries. An unusually high fraction of the deca-chlorinated congener (PCB-209) was found in all media. Seen in only a few other studies and in previous air concentrations in the channel, this may point to unusual Aroclor mixtures used in the history of the HSC or to contemporary sources from local industry. A comparison of PCB concentrations obtained using Aroclor, representative congener, and all congener methods, indicated that Aroclors are not an appropriate surrogate for total PCBs and that the NOAA NST method is more representative than the NOAA EPA method. 相似文献
188.
Aishwarya Arjunan Holly Bellerose Raul Torres Rotem Ben-Shachar Jodi D. Hoffman Brad Angle Robert Nathan Slotnick Brittany N. Simpson Andrea M. Lewis Pilar L. Magoulas Kelly Bontempo Jeanine Schulze Jennifer Tarpinian Jessica A. Bucher Richard Dineen Allison Goetsch Gabriel A. Lazarin Katherine Johansen Taber 《黑龙江环境通报》2020,40(10):1246-1257
Background
Disease severity is important when considering genes for inclusion on reproductive expanded carrier screening (ECS) panels. We applied a validated and previously published algorithm that classifies diseases into four severity categories (mild, moderate, severe, and profound) to 176 genes screened by ECS. Disease traits defining severity categories in the algorithm were then mapped to four severity-related ECS panel design criteria cited by the American College of Obstetricians and Gynecologists (ACOG).Methods
Eight genetic counselors (GCs) and four medical geneticists (MDs) applied the severity algorithm to subsets of 176 genes. MDs and GCs then determined by group consensus how each of these disease traits mapped to ACOG severity criteria, enabling determination of the number of ACOG severity criteria met by each gene.Results
Upon consensus GC and MD application of the severity algorithm, 68 (39%) genes were classified as profound, 71 (40%) as severe, 36 (20%) as moderate, and one (1%) as mild. After mapping of disease traits to ACOG severity criteria, 170 out of 176 genes (96.6%) were found to meet at least one of the four criteria, 129 genes (73.3%) met at least two, 73 genes (41.5%) met at least three, and 17 genes (9.7%) met all four.Conclusion
This study classified the severity of a large set of Mendelian genes by collaborative clinical expert application of a trait-based algorithm. Further, it operationalized difficult to interpret ACOG severity criteria via mapping of disease traits, thereby promoting consistency of ACOG criteria interpretation.189.
We examined whether sexualizing a businesswoman impacts attitudes toward subsequently evaluated, nonsexualized females applying for a corporate managerial position. Research shows that sexualized women are perceived as less warm and competent (i.e., objectified). Integrating this work with research on social cognition, we hypothesized that the negative effect of sexualization “spills over” onto other nonsexualized women, reducing their hireability. Across two experiments, initially sexualized women were perceived as less warm and competent, as were subsequently evaluated nonsexualized female job candidates. In turn, these negative perceptions reduced the applicants' probability of being hired. Sexualization of women also increased intentions to hire a subsequently evaluated male candidate. The results were robust when we controlled for evaluators' gender and age. Our findings demonstrate that female job applicants can experience detrimental effects from sexually based objectification, even when they are not the individuals initially sexualized. We discuss implications for women's careers. 相似文献
190.
In this paper we examine the characteristics of near-inertial internal Poincaré waves in Lake Michigan (USA) as discerned from field experiments and hydrodynamic simulations. The focus is on the determination of the lateral and vertical structure of the waves. Observations of near-inertial internal wave properties are presented from two field experiments in southern Lake Michigan conducted during the years 2009 and 2010 at Michigan City (IN, USA) and Muskegon (MI, USA), respectively. Spectra of thermocline displacements and baroclinic velocities show that kinetic and potential baroclinic energy is dominated by near-inertial internal Poincaré waves. Vertical structure discerned from empirical orthogonal function analysis shows that this energy is predominantly vertical mode 1. Idealized hydrodynamic simulations using stratifications from early summer (June), mid-summer (July) and fall (September) identify the basin-scale internal Poincaré wave structure as a combination of single- and two-basin cells, similar to those identified in Lake Erie by Schwab, with near-surface velocities largest in the center of the northern and southern basins. Near-inertial bottom kinetic energy is seen to have roughly constant magnitude over large swathes across the basin, with higher magnitude in the shallower areas like the Mid-lake Plateau, as compared with the deep northern and southern basins. The near-bottom near-inertial kinetic energy when mapped appears similar to the bottom topography map. The wave-induced vertical shear across thermocline is concentrated along the longitudinal axis of the lake basin, and both near-bottom velocities and thermocline shear are reasonably explained by a simple conceptual model of the expected transverse variability. 相似文献