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201.
202.
Partnerships between organisations in humanitarian crisis situations generally are challenging, but at the apex are those established as part of remote management in a context of extreme insecurity. To date, little systematic research has been conducted on arrangements between local organisations that have access to crisis‐affected populations and international organisations that hold the purse strings. This paper presents the findings of nine months of qualitative research conducted with five Syrian local organisations and their international partners engaging in humanitarian action across the Turkey–Syria border, and presents insights into the components of successful partnerships. It redefines capacity along organisational and operational lines, and unpacks how monitoring and evaluation and donor requirements create tension and, at times, place local organisations at risk. The paper highlights the centrality of trust in successful partnerships, and describes the personalisation of the conflict by local organisations. Based on a historical case study of civil society in northern Iraq, it closes with some suggestions for long‐term sustainability. 相似文献
203.
AbstractAtrazine, an endocrine-disrupting compound and environmental pollutant, can have adverse effects on amphibian reproductive development and function. To determine the effects of atrazine on anuran gonadal development, Lithobates pipiens larvae were exposed from Gosner stage 25 through 1-month post metamorphosis to 0, 2, 20, or 200?μg/L atrazine or estradiol. Exposure to atrazine did not markedly alter tadpole growth, development, gonadal histology, or reproductive steroidogenesis. Testicular ovarian follicles appeared in L. pipiens metamorphs following all treatments, including controls, whereas ovotestes occurred only in positive controls. Testicular ovarian follicles may be a natural ontogenetic occurrence in this species while ovotestes indicate disruption in development. Establishing the normal pattern of reproductive development for anuran species and conducting comparisons in fully sexually differentiated animals is necessary to clarify the influence of endocrine disrupting compounds. 相似文献
204.
Chensheng Lu Teresa Rodriguez Anamai Thiravirojana-Thetkathuek Melanie Pearson 《毒物与环境化学》2013,95(2):315-325
The objective of this study was to determine the feasibility of using salivary biomarkers to assess chlorpyrifos exposure using data collected from laboratory controlled animal study, as well as from farmers in Thailand and Nicaragua who applied chlorpyrifos in the field. Time-matched saliva and arterial blood samples were collected from rats and adult agricultural workers, while spot saliva samples were collected from children. Specimen samples were analyzed for chlorpyrifos using a commercially available enzyme-linked immunosorbent assay. The results from both animal and farmer studies show that chlorpyrifos is excreted into saliva. Nevertheless, salivary excretion of chlorpyrifos seems to differ from other pesticides, as evidenced by the lack of correspondence of chlorpyrifos levels between saliva and plasma samples. The lower chlorpyrifos concentrations in saliva collected from rats, and from farmers and their children, may have resulted from the rapid hydrolysis of chlorpyrifos during the intracellular passive diffusion in the salivary gland. In conclusion, chlorpyrifos is excreted into saliva; however, the majority of chlorpyrifos that is excreted in saliva may have been metabolized due to base-dependent hydrolysis. Because of this finding, it was hypothesized that it would be ideal to measure its metabolite, 3,5,6-trichloropyridinol, in saliva as the biomarker for chlorpyrifos exposure. 相似文献
205.
Pilar Santidrián Tomillo Jack S. Suss Bryan P. Wallace Kimberly D. Magrini Gabriela Blanco Frank V. Paladino James R. Spotila 《Marine Biology》2009,156(10):2021-2031
Reproductive output of leatherback turtles (Dermochelys coriacea) is affected by the stochastic nature of emergence success. Average emergence success of nests at Playa Grande, Costa Rica
was 0.38 ± 0.27. Incubation temperature affected development of leatherback turtle eggs and emergence of hatchlings from the
nest. We found that high temperatures reduced hatching success and emergence rate and increased embryonic mortality both early
and late during incubation at Playa Grande. There was a temporal effect on emergence success that resulted in more hatchlings
being produced at the beginning of the season, because of higher emergence success, than toward the end. Likewise, production
of hatchlings varied from year to year. The average annual reproductive output was 252 ± 141 hatchlings per female. The 2005–2006
nesting season had the highest emergence success and produced the greatest number of hatchlings per female compared to the
2004–2005 (+120%) and 2006–2007 (+41%) seasons. However, average clutch size (62 ± 10) and clutch frequency (9.45 ± 1.63),
were not different among years. Turtles that had nested a high number of years exhibited greater clutch frequency and arrived
earlier to nest than turtles that had nested in fewer numbers of years. Nesting when environmental conditions favor high developmental
success and emergence rate may constitute an advantageous reproductive strategy. 相似文献
206.
Asunción Lago-Lestón Catarina Mota Lena Kautsky Gareth A. Pearson 《Marine Biology》2010,157(3):683-688
In the Baltic Sea, the broadly distributed brown alga Fucus vesiculosus coexists in sympatry over part of its range (south west Gulf of Bothnia) with the Baltic endemic F. radicans sp. nov, while further north in colder and lower-salinity areas of the Baltic F. radicans occurs alone (north west Gulf of Bothnia). F. radicans appears to have arisen via rapid speciation from F. vesiculosus within the recent history of the Baltic (ca. 7500 BP). Possible functional divergence between the two species was investigated
by comparing stress-responsive gene expression in a common-garden experiment. The experiment used two allopatric populations
of Fucus vesiculosus from the Skagerrak (North Sea) and Central Baltic, as well as F. radicans from the same Central Baltic site. The two species in sympatry displayed divergent heat shock responses, while F. vesiculosus populations from allopatric sites did not. F. radicans was more sensitive to heat shock at 25°C, either alone or together with high irradiance and desiccation, than Baltic or Skagerrak
F. vesiculosus. The results indicate that rapid functional divergence in the inducible heat shock response has occurred between sympatric
species on a timescale of thousands of years. 相似文献
207.
Amita A. Jatkar Barbara E. Brown John C. Bythell Reia Guppy Nicholas J. Morris Jeffery P. Pearson 《Marine Biology》2010,157(2):261-267
A method previously used to measure thickness of the surface mucus layer (SML) of the mammalian gastrointestinal tract has
been applied to the SML of reef corals. It involves manual measurement of mucus thickness using a micromanipulator and fine
glass needle (micropipette) and is non-destructive to the coral, meaning that repeated measurements can be taken. A measurable
mucus layer was recorded in all cases in the study, which comprised 450 individual thickness measurements from four coral
species. Mucus thickness ranged from 145 to 700 μm. Thus, whatever dynamic processes control mucus synthesis, secretion to
the tissue surface and subsequent release into the water column, a continuous mucosal barrier is maintained. A change in SML
thickness was recorded as a response to aerial exposure during the natural tidal cycle and to solar exposure-induced bleaching,
although the response due to bleaching varied between two studied species. The technique is rapid, cost-effective and a simple
means of assessing coral SML thickness, a variable that shows significant variation in relation to environmental conditions
and is likely to be an important health indicator in these organisms. 相似文献
208.
Egg release and settlement patterns of dioecious and hermaphroditic fucoid algae during the tidal cycle 总被引:1,自引:0,他引:1
The timing of gamete release by fucoid algae, although known to be restricted to calm days is not clearly understood within
a circadian time scale. The need for externally fertilizing species to avoid gamete dilution suggests that in wave-exposed
areas spawning may occur during particular tidal phases. However, this may differ between mating systems, as selfing species
may be less affected by gamete dilution. In this study, two different approaches were used to determine when egg release occurs
during the tidal cycle in two sister species with different mating systems. First, egg settlement of Fucus vesiculosus (dioecious) and Fucus spiralis (selfing hermaphrodite) was quantified on removable substrates (egg settlement disks) every day for 2 months and settlement
patterns were used to statistically estimate the radius of a circle that would encompass 99% of each patch of settled eggs
(the egg dispersal radius). Also, egg release was quantified every 2 h during the tidal cycle. A significantly larger egg
dispersal radius (P < 0.02) was found for F. spiralis than F. vesiculosus, and this difference was somewhat site dependent with a greater difference between species in exposed sites. The egg dispersal
radius was negatively correlated with significant wave height and positively correlated with sea surface temperature for both
the species (P < 0.05), with a greater effect of both the factors for F. spiralis than for F. vesiculosus. Egg release during the tidal cycle was variable between species and experiments, with F. vesiculosus releasing more eggs, later in the day, and at a lower tide, than F. spiralis, which released fewer eggs, throughout the day and at all tides. The dioecious species, F. vesiculosus, may have developed a specific adaptation for timing the egg release to periods when emersed in exposed habitats to avoid
rapid dilution of gametes that require outcrossing for fertilization. On the other hand, egg release for F. spiralis, which can self-fertilize, occurred both when emersed and immersed, suggesting this species has developed less synchrony
with specific environmental factors. Site dependence also suggests local wave conditions can modulate timing of release. The
data are consistent with the relaxation of the selective constraints of water motion on fertilization success in a selfing
hermaphrodite, relative to an obligate outcrossing species. Results support the idea that species with different mating systems
evolve different sensitivities to environmental cues for gamete release with specific implications for inbreeding and successful
external fertilization in the ocean. 相似文献
209.
Incorporating covariates into fisheries stock assessment models with application to Pacific herring.
We present a framework for evaluating the cause of fishery declines by integrating covariates into a fisheries stock assessment model. This allows the evaluation of fisheries' effects vs. natural and other human impacts. The analyses presented are based on integrating ecological science and statistics and form the basis for environmental decision-making advice. Hypothesis tests are described to rank hypotheses and determine the size of a multiple covariate model. We extend recent developments in integrated analysis and use novel methods to produce effect size estimates that are relevant to policy makers and include estimates of uncertainty. Results can be directly applied to evaluate trade-offs among alternative management decisions. The methods and results are also broadly applicable outside fisheries stock assessment. We show that multiple factors influence populations and that analysis of factors in isolation can be misleading. We illustrate the framework by applying it to Pacific herring of Prince William Sound, Alaska (USA). The Pacific herring stock that spawns in Prince William Sound is a stock that has collapsed, but there are several competing or alternative hypotheses to account for the initial collapse and subsequent lack of recovery. Factors failing the initial screening tests for statistical significance included indicators of the 1989 Exxon Valdez oil spill, coho salmon predation, sea lion predation, Pacific Decadal Oscillation, Northern Oscillation Index, and effects of containment in the herring egg-on-kelp pound fishery. The overall results indicate that the most statistically significant factors related to the lack of recovery of the herring stock involve competition or predation by juvenile hatchery pink salmon on herring juveniles. Secondary factors identified in the analysis were poor nutrition in the winter, ocean (Gulf of Alaska) temperature in the winter, the viral hemorrhagic septicemia virus, and the pathogen Ichthyophonus hoferi. The implication of this result to fisheries management in Prince William Sound is that it may well be difficult to simultaneously increase the production of pink salmon and maintain a viable Pacific herring fishery. The impact can be extended to other commercially important fisheries, and a whole ecosystem approach may be needed to evaluate the costs and benefits of salmon hatcheries. 相似文献
210.
The Theory of Conservation Biology 总被引:2,自引:0,他引:2
Kimberly A. With 《Conservation biology》1997,11(6):1436-1440