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991.
Schwegel Megan A. Filazzola Alessandro Chapman Colin A. Schoof Valérie A. M. 《International journal of primatology》2023,44(1):45-70
International Journal of Primatology - Resource availability is intricately linked to female reproductive success, and poor timing of reproduction can negatively impact maternal and/or infant... 相似文献
992.
Francine H. Mejia Valerie Ouellet Martin A. Briggs Stephanie M. Carlson Roser Casas-Mulet Mollie Chapman Mathias J. Collins Stephen J. Dugdale Joseph L. Ebersole Danielle M. Frechette Aimee H. Fullerton Carole-Anne Gillis Zachary C. Johnson Christa Kelleher Barret L. Kurylyk Rebecca Lave Benjamin H. Letcher Knut M. Myrvold Tracie-Lynn Nadeau Helen Neville Herve Piégay Kathryn A. Smith Diego Tonolla Christian E. Torgersen 《Global Change Biology》2023,29(19):5482-5508
Human activities and climate change threaten coldwater organisms in freshwater ecosystems by causing rivers and streams to warm, increasing the intensity and frequency of warm temperature events, and reducing thermal heterogeneity. Cold-water refuges are discrete patches of relatively cool water that are used by coldwater organisms for thermal relief and short-term survival. Globally, cohesive management approaches are needed that consider interlinked physical, biological, and social factors of cold-water refuges. We review current understanding of cold-water refuges, identify gaps between science and management, and evaluate policies aimed at protecting thermally sensitive species. Existing policies include designating cold-water habitats, restricting fishing during warm periods, and implementing threshold temperature standards or guidelines. However, these policies are rare and uncoordinated across spatial scales and often do not consider input from Indigenous peoples. We propose that cold-water refuges be managed as distinct operational landscape units, which provide a social and ecological context that is relevant at the watershed scale. These operational landscape units provide the foundation for an integrated framework that links science and management by (1) mapping and characterizing cold-water refuges to prioritize management and conservation actions, (2) leveraging existing and new policies, (3) improving coordination across jurisdictions, and (4) implementing adaptive management practices across scales. Our findings show that while there are many opportunities for scientific advancement, the current state of the sciences is sufficient to inform policy and management. Our proposed framework provides a path forward for managing and protecting cold-water refuges using existing and new policies to protect coldwater organisms in the face of global change. 相似文献
993.
Amy Trentham-Dietz Oguzhan Alagoz Christina Chapman Xuelin Huang Jinani Jayasekera Nicolien T. van Ravesteyn Sandra J. Lee Clyde B. Schechter Jennifer M. Yeh Sylvia K. Plevritis Jeanne S. Mandelblatt for the Breast Working Group of the Cancer Intervention Surveillance Modeling Network 《PLoS computational biology》2021,17(6)
Since 2000, the National Cancer Institute’s Cancer Intervention and Surveillance Modeling Network (CISNET) modeling teams have developed and applied microsimulation and statistical models of breast cancer. Here, we illustrate the use of collaborative breast cancer multilevel systems modeling in CISNET to demonstrate the flexibility of systems modeling to address important clinical and policy-relevant questions. Challenges and opportunities of future systems modeling are also summarized. The 6 CISNET breast cancer models embody the key features of systems modeling by incorporating numerous data sources and reflecting tumor, person, and health system factors that change over time and interact to affect the burden of breast cancer. Multidisciplinary modeling teams have explored alternative representations of breast cancer to reveal insights into breast cancer natural history, including the role of overdiagnosis and race differences in tumor characteristics. The models have been used to compare strategies for improving the balance of benefits and harms of breast cancer screening based on personal risk factors, including age, breast density, polygenic risk, and history of Down syndrome or a history of childhood cancer. The models have also provided evidence to support the delivery of care by simulating outcomes following clinical decisions about breast cancer treatment and estimating the relative impact of screening and treatment on the United States population. The insights provided by the CISNET breast cancer multilevel modeling efforts have informed policy and clinical guidelines. The 20 years of CISNET modeling experience has highlighted opportunities and challenges to expanding the impact of systems modeling. Moving forward, CISNET research will continue to use systems modeling to address cancer control issues, including modeling structural inequities affecting racial disparities in the burden of breast cancer. Future work will also leverage the lessons from team science, expand resource sharing, and foster the careers of early stage modeling scientists to ensure the sustainability of these efforts. 相似文献
994.
Jaspreet Toor Jonathan I. D. Hamley Claudio Fronterre María Soledad Castao Lloyd A. C. Chapman Luc E. Coffeng Federica Giardina Thomas M. Lietman Edwin Michael Amy Pinsent Epke A. Le Rutte T. Dirdre Hollingsworth 《PLoS neglected tropical diseases》2021,15(5)
Locally tailored interventions for neglected tropical diseases (NTDs) are becoming increasingly important for ensuring that the World Health Organization (WHO) goals for control and elimination are reached. Mathematical models, such as those developed by the NTD Modelling Consortium, are able to offer recommendations on interventions but remain constrained by the data currently available. Data collection for NTDs needs to be strengthened as better data are required to indirectly inform transmission in an area. Addressing specific data needs will improve our modelling recommendations, enabling more accurate tailoring of interventions and assessment of their progress. In this collection, we discuss the data needs for several NTDs, specifically gambiense human African trypanosomiasis, lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminths (STH), trachoma, and visceral leishmaniasis. Similarities in the data needs for these NTDs highlight the potential for integration across these diseases and where possible, a wider spectrum of diseases. 相似文献
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997.
Liposome supported peritoneal dialysis is a recently described technique which may eventually be applicable in the clinical scenario of the intoxicated patient. We evaluated the hypothesis that intravenous injection of lipid emulsion (ILE) would augment acidic pH gradient liposome supported peritoneal dialysis (LSPD). Orogastrically amitriptyline dosed rats were treated with either Sodium bicarbonate (NaHCO3) intravenously and standard intraperitoneal dialysate (Group A); NaHCO3 intravenously and LSPD (Group B); or ILE and LSPD (Group C). The primary endpoint was dialysate amitriptyline concentration after a 60?min dwell. Secondary analysis included an estimate of extraction ratio for peritoneal blood flow (ERs). There were significantly higher intraperitoneal concentrations of amitriptyline and ERs in the two groups treated with LSPD (Group B, p?=?0.02, Group C, p?<?0.01 vs. Group A). There was no observed effect for ILE on intraperitoneal amitriptyline concentration or ERs (p?>?0.20). LSPD increased the amitriptyline concentration in peritoneal dialysate. No further increase was demonstrated with ILE. This may be either because such an effect is absent, or type II error. Exploratory analysis suggests LSPD may be driven by total rather than free drug concentrations. 相似文献
998.
Low-dose pramlintide reduced food intake and meal duration in healthy, normal-weight subjects 总被引:1,自引:0,他引:1
Chapman I Parker B Doran S Feinle-Bisset C Wishart J Lush CW Chen K Lacerte C Burns C McKay R Weyer C Horowitz M 《Obesity (Silver Spring, Md.)》2007,15(5):1179-1186
Objective: We previously reported that a single preprandial injection (120 μg) of pramlintide, an analog of the β‐cell hormone amylin, reduced ad libitum food intake in obese subjects. To further characterize the meal‐related effects of amylin signaling in humans, we studied a lower pramlintide dose (30 μg) in normal‐weight subjects. Research Methods and Procedures: In a randomized, double‐blind, placebo‐controlled, cross‐over study, 15 healthy men (age, 24 ± 7 years; BMI, 22.2 ± 1.8 kg/m2) underwent a standardized buffet meal test on two occasions. After an overnight fast, subjects received a single subcutaneous injection of pramlintide (30 μg) or placebo, followed immediately by a standardized pre‐load meal. After 1 hour, subjects were offered an ad libitum buffet meal, and total caloric intake and meal duration were measured. Results: Compared with placebo, pramlintide reduced total caloric intake (1411 ± 94 vs. 1190 ± 117 kcal; Δ, ?221 ± 101 kcal; ?14 ± 9%; p = 0.05) and meal duration (36 ± 2 vs. 31 ± 3 minutes; Δ, ?5.1 ± 1.4 minutes; p < 0.005). Visual analog scale profiles of hunger trended lower and fullness higher during the first hour after pramlintide administration. In response to the buffet, hunger and fullness changed to a similar degree after pramlintide and placebo, despite subjects on pramlintide consuming 14% fewer kilocalories. Visual analog scale nausea ratings remained near baseline, without differences between treatments. Plasma peptide YY, cholecystokinin, and ghrelin concentrations did not differ with treatment, whereas glucagon‐like peptide‐1 concentrations after meals were lower in response to pramlintide than to placebo. Discussion: These observations add support to the concept that amylin agonism may have a role in human appetite control. 相似文献
999.
Effects of different concentrations of GF-120 NF Naturalyte Fruit Fly Bait on attraction and feeding responses, mortality, and control of the western cherry fruit fly, Rhagoletis indifferens Curran, were determined. In the laboratory, flies that had been exposed to sugar and yeast extract and then deprived of all food for 16-20 h were attracted to 40.0% GF-120, but not to 0.6 and 4.8% GF-120 (vol:vol). Nonstarved flies were not attracted to any concentration. Flies in the field were not attracted to 55.6% GF-120 on cherry leaves, and few flies fed on the bait. In the laboratory, males fed for shorter durations on and ingested lower amounts of 0.6% than 4.8 or 40.0% GF-120, but females fed equally on all concentrations. Spinosad in GF-120 was highly toxic to flies. Lethal concentrations50 (LC50 values) of spinosad for starved flies at 1-4 d were 1.5-0.7 ppm. When gravid flies were exposed to cherries treated with 0.6, 4.8, and 40.0% GF-120, mortality was greater at each higher concentration, but none prevented oviposition. Field spray tests comparing 0.6, 4.8, and 40.0% GF-120 in 225 ml of spray per cherry tree resulted in 79-94% lower larval infestations than in controls, but no differences were seen among the concentrations. Evidence from this study indicates that fresh 40.0% GF-120 was attractive in the laboratory but that flies were not attracted to fresh GF-120 from far distances within trees, suggesting that suppression of populations is caused in large part by flies finding the bait through normal movement over large areas. 相似文献
1000.
Regulation of Expression of Nitrate and Dinitrogen Assimilation by Anabaena Species 总被引:6,自引:1,他引:6 下载免费PDF全文
John C. Meeks Keith L. Wycoff John S. Chapman Carol S. Enderlin 《Applied microbiology》1983,45(4):1351-1359
Anabaena sp. strain 7120 appeared more responsive to nitrogen control than A. cylindrica. Growth in the presence of nitrate strongly repressed the differentiation of heterocysts and fixation of dinitrogen in Anabaena sp. strain 7120, but only weakly in A. cylindrica. Nitrate assimilation by ammonium-grown cultures was strongly repressed in Anabaena sp. strain 7120, but less so in A. cylindrica. The repressive effect of nitrate on dinitrogen assimilation in Anabaena sp. strain 7120, compared to A. cylindrica, did not correlate with a greater rate of nitrate transport, reduction to ammonium, assimilation into amino acids, or growth. Although both species grew at similar rates with dinitrogen, A. cylindrica grew faster with nitrate, incorporated more 13NO3− into amino acids, and assimilated (transported) nitrate at the same rate as Anabaena sp. strain 7120. Full expression of nitrate assimilation in the two species occurred within 2.5 h (10 to 14% of their generation times) after transfer to nitrate medium. The induction and continued expression of nitrate assimilation was dependent on protein synthesis. The half-saturation constants for nitrate assimilation and for nitrate and ammonium repression of dinitrogen assimilation have ecological significance with respect to nitrogen-dependent growth and competitiveness of the two Anabaena species. 相似文献