71 research outputs found

    Characterizing benthic macroinvertebrate and algal biological condition gradient models for California wadeable Streams, USA

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    The Biological Condition Gradient (BCG) is a conceptual model that describes changes in aquatic communities under increasing levels of anthropogenic stress. The BCG helps decision-makers connect narrative water quality goals (e.g., maintenance of natural structure and function) to quantitative measures of ecological condition by linking index thresholds based on statistical distributions (e.g., percentiles of reference distributions) to expert descriptions of changes in biological condition along disturbance gradients. As a result, the BCG may be more meaningful to managers and the public than indices alone. To develop a BCG model, biological response to stress is divided into 6 levels of condition, represented as changes in biological structure (abundance and diversity of pollution sensitive versus tolerant taxa) and function. We developed benthic macroinvertebrate (BMI) and algal BCG models for California perennial wadeable streams to support interpretation of percentiles of reference-based thresholds for bioassessment indices (i.e., the California Stream Condition Index [CSCI] for BMI and the Algal Stream Condition Index [ASCI] for diatoms and soft-bodied algae). Two panels (one of BMI ecologists and the other of algal ecologists) each calibrated a general BCG model to California wadeable streams by first assigning taxa to specific tolerance and sensitivity attributes, and then independently assigning test samples (264 BMI and 248 algae samples) to BCG Levels 1–6. Consensus on the assignments was developed within each assemblage panel using a modified Delphi method. Panels then developed detailed narratives of changes in BMI and algal taxa that correspond to the 6 BCG levels. Consensus among experts was high, with 81% and 82% expert agreement within 0.5 units of assigned BCG level for BMIs and algae, respectively. According to both BCG models, the 10th percentiles index scores at reference sites corresponded to a BCG Level 3, suggesting that this type of threshold would protect against moderate changes in structure and function while allowing loss of some sensitive taxa. The BCG provides a framework to interpret changes in aquatic biological condition along a gradient of stress. The resulting relationship between index scores and BCG levels and narratives can help decision-makers select thresholds and communicate how these values protect aquatic life use goals

    Biodiversity of the Deep-Sea Continental Margin Bordering the Gulf of Maine (NW Atlantic): Relationships among Sub-Regions and to Shelf Systems

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    Background: In contrast to the well-studied continental shelf region of the Gulf of Maine, fundamental questions regarding the diversity, distribution, and abundance of species living in deep-sea habitats along the adjacent continental margin remain unanswered. Lack of such knowledge precludes a greater understanding of the Gulf of Maine ecosystem and limits development of alternatives for conservation and management. Methodology/Principal Findings: We use data from the published literature, unpublished studies, museum records and online sources, to: (1) assess the current state of knowledge of species diversity in the deep-sea habitats adjacent to the Gulf of Maine (39–43uN, 63–71uW, 150–3000 m depth); (2) compare patterns of taxonomic diversity and distribution of megafaunal and macrofaunal species among six distinct sub-regions and to the continental shelf; and (3) estimate the amount of unknown diversity in the region. Known diversity for the deep-sea region is 1,671 species; most are narrowly distributed and known to occur within only one sub-region. The number of species varies by sub-region and is directly related to sampling effort occurring within each. Fishes, corals, decapod crustaceans, molluscs, and echinoderms are relatively well known, while most other taxonomic groups are poorly known. Taxonomic diversity decreases with increasing distance from the continental shelf and with changes in benthic topography. Low similarity in faunal composition suggests the deep-sea region harbours faunal communities distinct from those of the continental shelf. Non-parametric estimators of species richness suggest a minimum of 50% of the deep-sea species inventory remains to be discovered. Conclusions/Significance: The current state of knowledge of biodiversity in this deep-sea region is rudimentary. Our ability to answer questions is hampered by a lack of sufficient data for many taxonomic groups, which is constrained by sampling biases, life-history characteristics of target species, and the lack of trained taxonomists

    Practical guidelines for rigor and reproducibility in preclinical and clinical studies on cardioprotection

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    The potential for ischemic preconditioning to reduce infarct size was first recognized more than 30 years ago. Despite extension of the concept to ischemic postconditioning and remote ischemic conditioning and literally thousands of experimental studies in various species and models which identified a multitude of signaling steps, so far there is only a single and very recent study, which has unequivocally translated cardioprotection to improved clinical outcome as the primary endpoint in patients. Many potential reasons for this disappointing lack of clinical translation of cardioprotection have been proposed, including lack of rigor and reproducibility in preclinical studies, and poor design and conduct of clinical trials. There is, however, universal agreement that robust preclinical data are a mandatory prerequisite to initiate a meaningful clinical trial. In this context, it is disconcerting that the CAESAR consortium (Consortium for preclinicAl assESsment of cARdioprotective therapies) in a highly standardized multi-center approach of preclinical studies identified only ischemic preconditioning, but not nitrite or sildenafil, when given as adjunct to reperfusion, to reduce infarct size. However, ischemic preconditioning—due to its very nature—can only be used in elective interventions, and not in acute myocardial infarction. Therefore, better strategies to identify robust and reproducible strategies of cardioprotection, which can subsequently be tested in clinical trials must be developed. We refer to the recent guidelines for experimental models of myocardial ischemia and infarction, and aim to provide now practical guidelines to ensure rigor and reproducibility in preclinical and clinical studies on cardioprotection. In line with the above guideline, we define rigor as standardized state-of-the-art design, conduct and reporting of a study, which is then a prerequisite for reproducibility, i.e. replication of results by another laboratory when performing exactly the same experiment

    Translating LA : a tour of the Rainbow City /

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    Writing the world: American authors looking outward

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    Peter Hessler was the The New Yorker\u27s correspondent in the People’s Republic of China, from 1996 to 2008. His first book, River Town: Two Years on the Yangtze, which recounts his experiences during two years in the Peace Corps, won the Kiriyama Prize and was short-listed for the Thomas Cook Travel Book Award. His second book, Oracle Bones, was a finalist for the 2006 National Book Award. His newest book, Country Driving: A Journey from Farm to Factory, a record of his journey from northern Chinese counties to the factory towns on southern China, appeared in 2010. His stories have been published in the Best American Travel Writing for 2001, 2004, and 2005. Paul Theroux’s highly acclaimed novels include Picture Palace (winner of the Whitbread Prize for Fiction), Hotel Honolulu, My Other Life, Kowloon Tong, and The Mosquito Coast (adapted into a major motion picture). He has also published chronicles of his own travels by train throughout the world in renowned travel books, including Ghost Train to the Eastern Star, Dark Star Safari, Riding the Iron Rooster, The Great Railway Bazaar, The Old Patagonian Express, and The Happy Isles of Oceania. He lives in Hawaii and on Cape Cod. Mary-Ann Tirone Smith is the author of eight novels, and co-author of a ninth. Her book Girls of Tender Age: A Memoir examines the murder of a classmate and her brother\u27s undiagnosed autism (both taboo subjects for discussion in the nineteen-fifties working-class neighborhood of her childhood); it was selected by Maureen Corrigan, of National Public Radio, as one of the best works of nonfiction of 2006, and has been widely read by discussion groups and book clubs. A former Peace Corps volunteer in Cameroon, Mary-Ann has taught fiction writing at Fairfield University and participated in writing seminars throughout the country, as well as in Ireland. Her book reviews have appeared in The New York Times, the Hartford Courant, the Boston Globe, and others. She lives in Connecticut. Marnie Mueller is the author of three novels: Green Fires, partially based on her Peace Corps experiences in Ecuador; The Climate of the Country, set in Tule Lake Japanese American Segregation Camp where Mueller was born; and My Mother’s Island, set in her family’s Puerto Rico. Recipient of an American Book Award from the Before Columbus Foundation, her work has been singled out by Barnes and Noble Discover Great New Writers, the New York Times Book Review, and BookSense. Her current project is a non-fiction book, Triple Threat: The Life and Times of Mary Mon Toy Okada, about a Japanese-American showgirl interned during World War II

    Study protocol for FUTURES: Testing a web-based reproductive health education program for adolescent and young adult males with sickle cell disease.

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    Individuals with sickle cell disease are increasingly surviving into adulthood, many of whom have interest in future biological parenthood. Reproductive health knowledge is low among adolescent and young adult males and their caregivers. Their understanding of these topics is needed to optimize their reproductive health outcomes. As such, through collaboration with a community advisory board (adolescents and young adults with sickle cell disease and mothers of adolescent and young adult males with sickle cell disease) and digital design team, we developed a web-based sickle cell disease-focused reproductive health program entitled FUTURES to address these knowledge gaps. For phase I of this two phase feasibility and acceptability study, adolescent and young adult males and their caregivers will complete a pre- and post-program reproductive health knowledge and attitudes questionnaire to assess change in knowledge. In phase II, after learning about fertility testing as part of the FUTURES curriculum, adolescent and young adult male participants are given the option to pursue testing. The two-phase study aims to: 1) develop and test the feasibility, acceptability, and efficacy of a reproductive health web-based educational program at increasing reproductive health knowledge in male adolescent and young adult males with sickle cell disease and their caregivers, and 2) assess feasibility of fertility testing. The long-term goal is to improve reproductive and psychosocial outcomes among adolescent and young adult males with sickle cell disease
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