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131.
Forty-two communities in rural Alaska are considered unserved or underserved with water and sewer infrastructure. Many challenges exist to provide centralized piped water and sewer infrastructure to the homes, and they are exacerbated by decreasing capital funding. Unserved communities in rural Alaska experience higher rates of disease, supporting the recommendation that sanitation infrastructure should be provided. Organizations are pursuing alternative solutions to conventional piped water and sewer in order to maximize water use and reuse for public health. This paper reviews initiatives led by the State of Alaska, the Alaska Native Tribal Health Consortium, and the Yukon Kuskokwim Health Corporation to identify and develop potential long-term solutions appropriate and acceptable to rural communities. Future developments will likely evolve based on the lessons learned from the initiatives. Recommendations include Alaska-specific research needs, increased end-user participation in the design process, and integrated monitoring, evaluation, and information dissemination in future efforts.  相似文献   
132.
Chlordecone is an organochlorine pesticide, used in the Lesser Antilles from 1972 to 1993 to fight against a banana weevil. That molecule is very persistent in the natural environment and ends up in the sea with runoff waters. The objective of the present study is to evaluate the level of contamination in several trophic groups of marine animals according to their distance from the source of pollution. Samples of suspended matter, macroalgae, herbivorous fishes, detrivorous crustaceans, zooplanktivorous fishes, first- and second-order of carnivorous fishes, and piscivorous fishes have been collected in two sites, located downstream the contaminated sites (Goyave and Petit-Bourg), in three marine habitats (coastal mangroves, seagrass beds located 1.5 km from the shoreline, and coral reefs at 3 km offshore). Animals collected in mangroves were the most contaminated (mean concentrations 193 μg kg?1 in Goyave and 213 μg kg?1 in Petit-Bourg). Samples from seagrass beds presented intermediate concentrations of chlordecone (85 μg kg?1 in Goyave and 107 μg kg?1 in Petit-Bourg). Finally, samples from coral reefs were the less contaminated (71 μg kg?1 in Goyave and 74 μg kg?1 in Petit-Bourg). Reef samples, collected 3 km offshore, were two to three times less contaminated than those collected in mangroves.  相似文献   
133.
The effectiveness of environmental protection measures is based on the early identification and diagnosis of anthropogenic pressures. Similarly, restoration actions require precise monitoring of changes in the ecological quality of ecosystems, in order to highlight their effectiveness. Monitoring the ecological quality relies on bioindicators, which are organisms revealing the pressures exerted on the environment through the composition of their communities. Their implementation, based on the morphological identification of species, is expensive because it requires time and experts in taxonomy. Recent genomic tools should provide access to reliable and high-throughput environmental monitoring by directly inferring the composition of bioindicators’ communities from their DNA (metabarcoding). The French-Swiss program SYNAQUA (INTERREG France-Switzerland 2017–2019) proposes to use and validate the tools of environmental genomic for biomonitoring and aims ultimately at their implementation in the regulatory bio-surveillance. SYNAQUA will test the metabarcoding approach focusing on two bioindicators, diatoms, and aquatic oligochaetes, which are used in freshwater biomonitoring in France and Switzerland. To go towards the renewal of current biomonitoring practices, SYNAQUA will (1) bring together different actors: scientists, environmental managers, consulting firms, and biotechnological companies, (2) apply this approach on a large scale to demonstrate its relevance, (3) propose robust and reliable tools, and (4) raise public awareness and train the various actors likely to use these new tools. Biomonitoring approaches based on such environmental genomic tools should address the European need for reliable, higher-throughput monitoring to improve the protection of aquatic environments under multiple pressures, guide their restoration, and follow their evolution.  相似文献   
134.
Efforts are on the way on the Swedish West Coast to develop the capacity for cultivation of marine resources, notably of kelps. Given that this is a region of great natural and national heritage, public opposition to marine developments has been identified as a possible risk factor. This survey thus sought to shed light on awareness levels, perceptions of different types of aquaculture and on reactions to a scenario depicting future aquaculture developments on the West Coast. When asked about their general opinions of aquaculture, respondents tended to be favourable though a majority chose neutral responses. On the whole, respondents were favourable to the depicted scenario. Finally, it was found that the high-awareness group tended to be more supportive than the low or medium-awareness groups, hinting at the benefits of increasing awareness to reduce public aversion and to support a sustainable development of aquaculture on the Swedish West Coast.  相似文献   
135.
Environmental Science and Pollution Research - Multi-biological level assessments have become great tools to evaluate the health of aquatic ecosystems. Using this approach, a complementary study...  相似文献   
136.
Abstract

The aim of this study was to produce Bacillus thuringiensis-based biopesticide using starch-producing industry wastewater (SIW) fortified with soybean medium and optimize the formulated product using different adjuvants. This study was necessary as low endotoxin concentration is obtained in formulated biopesticide when SIW alone is used as fermentation medium. The fermentation runs were conducted using SIW alone and SIW fortified with 25% soybean (w/v) medium in 2000?L and 150?L bioreactor, respectively. SIW supplemented with soybean medium showed an increase in cell count (from 1.95?×?108 to 1.65?×?109 CFU mL–1), spore synthesis (from 1.5?×?108 to 1.35?×?109 CFU mL–1) and endotoxin concentration (from 436 to 1170?μg mL–1) when compared to SIW medium alone. The fermented broth was concentrated using continuous centrifugation and adjuvants were added for biopesticide formulation in order to enhance its resistance against UV rays and rainfastness. Entomotoxicity of the formulation produced using fermented broth of SIW fortified with soybean (38,000?IU μL–1) was higher than that obtained by SIW medium alone (21,000?IU μL–1), commercial biopesticide Foray 76B (20,000?IU μL–1) and Btk sander’s (12,500?IU μL–1).  相似文献   
137.
Abstract

Monensin (MON) is a coccidiostat used as a growth promoter that can reach the environment through fertilization with manure from farm animals. To verify whether field-relevant concentrations of this drug negatively influence the structure and activity of tropical soil bacteria, plate counts, CO2 efflux measurements, phospholipid fatty acids (PLFA) and community-level physiological profiling (CLPP) profiles were obtained for soil microcosms exposed to 1 or 10?mg kg?1 of MON across 11?days. Although 53% (1?mg kg?1) to 40% (10?mg kg?1) of the MON concentrations added to the microcosms dissipated within 5?days, a subtle concentration-dependent decrease in the number of culturable bacteria (<1 log CFU g?1), reduced (?20 to ?30%) or exacerbated (+25%) soil CO2 effluxes, a marked shift of non-bacterial fatty acids, and altered respiration of amines (1.22-fold decrease) and polymers (1.70-fold increase) were noted in some of the treatments. These results suggest that MON quickly killed some microorganisms and that the surviving populations were selected and metabolically stimulated. Consequently, MON should be monitored in agronomic and environmental systems as part of One Health efforts.  相似文献   
138.
Abstract

In the present study, ethanolic extract from Heliopsis longipes roots and affinin/spilanthol against Aspergillus parasiticus growth and aflatoxins production were studied in relation to the expression of aflD and aflR, two key genes of aflatoxins biosynthetic pathway. Phytochemical analysis of the ethanolic extract by GC-EIMS identified affinin/spilanthol (7.84?±?0.27?mg g?1) as the most abundant compounds in H. longipes roots. The antifungal and anti-aflatoxigenic assays showed that affinin/spilanthol at 300?µg mL?1 produced the higher inhibition of radial growth (95%), as well as, the higher aflatoxins production inhibition (61%) in comparison to H. longipes roots (87% and 48%, respectively). qRT-PCR revealed that the expression of aflD and aflR genes showed a higher downregulation in affinin/spilanthol at 300?µg mL?1. The expression ratio of alfD was suppressed by affinin/spilanthol in 79% and aflR in 84%, while, a lower expression ratio suppressed by H. longipes was obtained, alfD (55%) and aflR (59%). Affinin/spilanthol possesses higher antifungal and anti-aflatoxigenic activity against A. parasiticus rather than H. longipes roots, and this anti-aflaxotigenic activity occurring via downregulation of the aflD and aflR genes. Thus, H. longipes roots and affinin/spilanthol can be considered potent antifungal agents against aflatoxigenic fungus, especially, affinin/spilanthol.  相似文献   
139.
Abstract

Organochlorine pesticides (OCPs) are widely used around the world as insecticides, herbicides, fungicides, nematicides, and rodenticides. Despite banned in Brazil, the usage remains occurring in many countries. The persistence and extreme mobility of OCPs contribute to the contamination of the environment and the human body. The OCPs bioaccumulation in adipose tissue triggers the excretion into human milk during breastfeeding. Hence, the present study determined eighteen OCPs residues in the breast milk of mothers from the Western Region of Bahia State, Brazil. Nine different residue species were found, including beta-Hexachlorocyclohexane (9.24?±?0.00?ng g?1 fat), delta- Hexachlorocyclohexane (22.15?±?10.48?ng g?1 fat), Heptachlor (58.08?±?74.13?ng g?1 fat), Aldrin (142.65?±?50.65?ng g?1 fat), Dieldrin (774.62?±?472.68?ng g?1 fat), Endosulfan I (408.44?±?245.51?ng g?1 fat), Dichloro-diphenyl-dichloro-ethylene (29.17?±?22.42?ng g?1 fat), Dichloro-diphenyl-trichloro-ethane (28.87?±?0.00?ng g?1 fat) and Methoxychlor (1699.67?±?797.43?ng g?1 fat). The Methoxychlor presence in all samples may reveal a recent exposure, while Dieldrin and Endosulfan I analyses can point to distant past exposure.  相似文献   
140.
Little research has been conducted on the occurrence of pharmaceuticals and personal care products (PPCPs) in the marine environment despite being increasingly impacted by these contaminants. This article reviews data on the occurrence of PPCPs in seawater, sediment, and organisms in the marine environment. Data pertaining to 196 pharmaceuticals and 37 personal care products reported from more than 50 marine sites are analyzed while taking sampling strategies and analytical methods into account. Particular attention is focused on the most frequently detected substances at highest concentrations. A snapshot of the most impacted marine sites is provided by comparing the highest concentrations reported for quantified substances. The present review reveals that: (i) PPCPs are widespread in seawater, particularly at sites impacted by anthropogenic activities, and (ii) the most frequently investigated and detected molecules in seawater and sediments are antibiotics, such as erythromycin. Moreover, this review points out other PPCPs of concern, such as ultraviolet filters, and underlines the scarcity of data on those substances despite recent evidence on their occurrence in marine organisms. The exposure of marine organisms in regard to these insufficient data is discussed.  相似文献   
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