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21.
Conservation is an important organizational focus for zoos and aquariums. Organizational identity theory predicts a relationship between what is central to organizations, such as their mission statements, and their strategic activities. Based on this theory, we tested how organizational missions relate to their conservation strategies and practices. Tax forms and websites provided data from 173 zoos and 38 aquariums in the Association of Zoos and Aquariums in North America. We analyzed conservation mission strength, organizational characteristics, and project features with dependent variables representing the depth of organizational conservation commitments: amount of grants zoos funded, number of partner organizations, and number of projects per zoo. On tax forms, the average amount of total conservation grants donated to partner organizations per zoo was over $650,000, while the average number of partners reported on the tax forms was two. The content analysis of websites revealed an average of 14 conservation partners and 10 projects per zoo. Negative binomial regression models were significant. The financial analysis revealed that only the number of zoo personnel, as a surrogate for organization size, significantly predicted the amount of zoos’ conservation grants. Website analyses found increasing budgets, organizational involvement, and geographic reach of the projects predicted increasing numbers of conservation projects and partnerships. However, our findings did not support the hypothesized relationship—strength of organizational mission did not predict strategy and activities. Zoos could do more to strategically activate their organizational identities and conservation missions to achieve their conservation goals.  相似文献   
22.
The presence of Neotyphodium endophyte in forage grass tillers has been associated with increased tolerance of abiotic stresses. The effect of four endophyte treatments (plants with three different strains of Neotyphodium lolii compared with plants without endophyte) on superoxide dismutase (SOD) (EC1.15.1.1) activity in Lolium perenne cv ‘Grasslands Samson’ was measured under high and low dehydration regimes in a glasshouse experiment. SOD activity was assayed by a microplate method utilising the inhibition of reduction of a tetrazolium dye by superoxide radicals. A progressive increase in dehydration over 2 weeks reduced shoot fresh weight, dry weight and shoot water content for high, compared with low, moisture-stressed plants. Mean shoot fresh weight was significantly lower for plants with strain AR37 endophyte than for plants with strain AR1 endophyte, wild-type or endophyte-free plants, but there was no interaction between endophyte treatment and dehydration treatment. There were no differences in mean SOD activity between the dehydration treatments, and the four endophyte treatments at any of the harvests. All harvest mean SOD levels for plants in both stress groups, however, were significantly different from the preceding harvest value. Between the first and second week of moisture stress there was a significant endophyte by harvest interaction for mean percentage change in SOD activity when activity in plants with wild-type strain endophyte increased more rapidly than in AR1, AR37 or endophyte-free plants. The results are in agreement with earlier reports suggesting that Neotyphodium endophytes do not have major effects on the water stress physiology of perennial ryegrass, although water deficits applied were not extreme.  相似文献   
23.
The RXopJ4 resistance locus from the wild accession Solanum pennellii (Sp) LA716 confers resistance to bacterial spot disease of tomato (S. lycopersicum, Sl) caused by Xanthomonas perforans (Xp). RXopJ4 resistance depends on recognition of the pathogen type III effector protein XopJ4. We used a collection of Sp introgression lines (ILs) to narrow the RXopJ4 locus to a 4.2-Mb segment on the long arm of chromosome 6, encompassed by the ILs 6-2 and 6-2-2. We then adapted or developed a collection of 14 molecular markers to map on a segregating F2 population from a cross between the susceptible parent Sl FL8000 and the resistant parent RXopJ4 8000 OC7. In the F2 population, a 190-kb segment between the markers J350 and J352 cosegregated with resistance. This fine mapping will enable both the identification of candidate genes and the detection of resistant plants using cosegregating markers. The RXopJ4 resistance gene(s), in combination with other recently characterized genes and a quantitative trait locus (QTL) for bacterial spot disease resistance, will likely be an effective tool for the development of durable resistance in cultivated tomato.  相似文献   
24.
The financial crisis in Greece is largely impinging on the health and mental health of the population, raising concerns about a potential rise in suicide rates. The aim of this study was to explore changes in suicidal ideation and reported suicide attempts between 2009 and 2011 in a representative sample of the population and in several population subgroups. The socio‐economic predictors of suicidal ideation and suicide attempts in 2011 were also investigated. Two nationwide cross‐sectional telephone surveys were conducted in 2009 and 2011 using the same methodology. A random and representative sample of 2192 and 2256 people, respectively, took part in the surveys. Between 2009 and 2011, there was a substantial increase in the prevalence of suicidal ideation and reported suicide attempts. People suffering from depression, men, married individuals, people experiencing financial strain, people with low interpersonal trust, and individuals with a history of suicide attempts were particularly vulnerable.  相似文献   
25.
Cerium oxide nanoparticles (nanoceria) possess catalytic and regenerative radical scavenging activities. The ability of nanoceria to maintain cellular redox balance makes them ideal candidates for treatment of retinal diseases whose development is tightly associated with oxidative damage. We have demonstrated that our stable water-dispersed nanoceria delay photoreceptor cell degeneration in rodent models and prevent pathological retinal neovascularization in vldlr mutant mice. The objectives of the current study were to determine the temporal and spatial distributions of nanoceria after a single intravitreal injection, and to determine if nanoceria had any toxic effects in healthy rat retinas. Using inductively-coupled plasma mass spectrometry (ICP-MS), we discovered that nanoceria were rapidly taken up by the retina and were preferentially retained in this tissue even after 120 days. We also did not observe any acute or long-term negative effects of nanoceria on retinal function or cytoarchitecture even after this long-term exposure. Because nanoceria are effective at low dosages, nontoxic and are retained in the retina for extended periods, we conclude that nanoceria are promising ophthalmic therapeutics for treating retinal diseases known to involve oxidative stress in their pathogeneses.  相似文献   
26.

Background

Primaquine is the only drug consistently effective against mature gametocytes of Plasmodium falciparum. The transmission blocking dose of primaquine previously recommended was 0.75mg/kg (adult dose 45mg) but its deployment was limited because of concerns over haemolytic effects in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency. G6PD deficiency is an inherited X-linked enzymatic defect that affects an estimated 400 million people around the world with high frequencies (15–20%) in populations living in malarious areas. To reduce transmission in low transmission settings and facilitate elimination of P. falciparum, the World Health Organization now recommends adding a single dose of 0.25mg/kg (adult dose 15mg) to Artemisinin-based Combination Therapies (ACTs) without G6PD testing. Direct evidence of the safety of this low dose is lacking. Adverse events and haemoglobin variations after this treatment were assessed in both G6PD normal and deficient subjects in the context of targeted malaria elimination in a malaria endemic area on the North-Western Myanmar-Thailand border where prevalence of G6PD deficiency (Mahidol variant) approximates 15%.

Methods and Findings

The tolerability and safety of primaquine (single dose 0.25 mg base/kg) combined with dihydroartemisinin-piperaquine (DHA-PPQ) given three times at monthly intervals was assessed in 819 subjects. Haemoglobin concentrations were estimated over the six months preceding the ACT + primaquine rounds of mass drug administration. G6PD deficiency was assessed with a phenotypic test and genotyping was performed in male subjects with deficient phenotypes and in all females. Fractional haemoglobin changes in relation to G6PD phenotype and genotype and primaquine round were assessed using linear mixed-effects models. No adverse events related to primaquine were reported during the trial. Mean fractional haemoglobin changes after each primaquine treatment in G6PD deficient subjects (-5.0%, -4.2% and -4.7%) were greater than in G6PD normal subjects (0.3%, -0.8 and -1.7%) but were clinically insignificant. Fractional drops in haemoglobin concentration larger than 25% following single dose primaquine were observed in 1.8% of the population but were asymptomatic.

Conclusions

The single low dose (0.25mg/kg) of primaquine is clinically well tolerated and can be used safely without prior G6PD testing in populations with high prevalence of G6PD deficiency. The present evidence supports a broader use of low dose primaquine without G6PD testing for the treatment and elimination of falciparum malaria.

Trial Registration

ClinicalTrials.gov NCT01872702  相似文献   
27.
28.
The seminal vesicles are male accessory sex glands that contribute the major portion of the seminal plasma in which mammalian spermatozoa are bathed during ejaculation. In addition to conveying sperm through the ejaculatory duct, seminal vesicle secretions support sperm survival after ejaculation, and influence the female reproductive tract to promote receptivity to pregnancy. Analysis of seminal vesicle fluid (SVF) composition by proteomics has proven challenging, due to its highly biased protein signature with a small subset of dominant proteins and the difficulty of solubilizing this viscous fluid. As such, publicly available proteomic datasets identify only 85 SVF proteins in total. To address this limitation, we report a new preparative methodology involving sequential solubilization of mouse SVF in guanidine hydrochloride, acetone precipitation, and analysis by label-free mass spectrometry. Using this strategy, we identified 126 SVF proteins, including 83 previously undetected in SVF. Members of the seminal vesicle secretory protein family were the most abundant, accounting for 79% of all peptide spectrum matches. Functional analysis identified inflammation and formation of the vaginal plug as the two most prominent biological processes. Other notable processes included modulation of sperm function and regulation of the female reproductive tract immune environment. Together, these findings provide a robust methodological framework for future SVF studies and identify novel proteins with potential to influence both male and female reproductive physiology.  相似文献   
29.
Abstract Enrichment cultures from marine sediments mineralized benzene while using sulfate as the terminal electron acceptor. Parallel cultures using river marsh sediment displayed no activity. Mineralization was confirmed by release of 14CO2 from radiolabeled benzene. The dependence on sulfate reduction was demonstrated by stoichiometric balances and the use of specific inhibitors. This work supports recent observations that anaerobic benzene degradation takes place coupled to sulfate reduction.  相似文献   
30.
Nrdp1 is a RING finger-containing E3 ubiquitin ligase that physically interacts with and regulates steady-state cellular levels of the ErbB3 and ErbB4 receptor tyrosine kinases and has been implicated in the degradation of the inhibitor-of-apoptosis protein BRUCE. Here we demonstrate that the Nrdp1 protein undergoes efficient proteasome-dependent degradation and that mutations in its RING finger domain that disrupt ubiquitin ligase activity enhance stability. These observations suggest that Nrdp1 self-ubiquitination and stability could play an important role in regulating the activity of this protein. Using affinity chromatography, we identified the deubiquitinating enzyme USP8 (also called Ubpy) as a protein that physically interacts with Nrdp1. Nrdp1 and USP8 could be coimmunoprecipitated, and in transfected cells USP8 specifically bound to Nrdp1 but not cbl, a RING finger E3 ligase involved in ligand-stimulated epidermal growth factor receptor down-regulation. The USP8 rhodanese and catalytic domains mediated Nrdp1 binding. USP8 markedly enhanced the stability of Nrdp1, and a point mutant that disrupts USP8 catalytic activity destabilized endogenous Nrdp1. Our results indicate that Nrdp1 is a specific target for the USP8 deubiquitinating enzyme and are consistent with a model where USP8 augments Nrdp1 activity by mediating its stabilization.  相似文献   
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