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j.urnal of Water Resource and Protection 2018年第8期10卷 740-761页

作者： nancy j. leland j.mes F. Haney Lim-Tex North Andover MA USA Department of Zoology University of New Hampshire Durham NH USA

The management of cyanobacteria and potential exposure to associated biotoxins requires the allocation of scarce resources across a range of freshwater resources within various j.risdictions. Cost effective and reliable methods for sample processing and analysis form the foundation of the protocol yielding reliable data from which to derive important decisions. In this study the utilization of new methods to collect, process and analyze samples enhanced our ability to evaluate cyanobacterial populations. Extraction of phycocyanin using the single freeze thaw method provided more accurate and precise measurements (CV 4.7% and 6.4%), offering a simple and cost-effective means to overcome the influence of morphological variability. In-vacuo concentration of samples prior to ELISA analysis provided a detection limit of 0.001 μg·L?1 MC. Fractionation of samples (?1) = ?0.279 + (1.368 ? Log PC (μg·L?1) while in an Aphanizomemon spp. dominant system Log MC (ng·L?1) = 0.385 + (0.449 ? Log PC (μg·L?1). These methods and sampling protocol could be used in other aquatic systems across a broader regional landscape to estimate the levels of microcystins.

关键词： Cyanobacteria Size Fractions Fluorometry Monitoring Phycocyanin Extraction

Trophic Interactions between Anadromous j.venile Alewife (<i>Alosa pseudoharengus</i>) and Cyanobacterial Populations in a Shallow Mesotrophic Pond

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Natural Resources 2020年第9期11卷 394-419页

作者： nancy j. leland Ryan A. Landon j.mes F. Haney Department of Zoology University of New Hampshire Durham NH USA Lim-Tex North Andover MA USA

Alosa pseudoharengus is an anadromous fish that migrates from marine to freshwaters to spawn. The early larval and j.venile forms are known to be planktivorous, where heavy feeding upon their preferred food source of ... 详细信息

Alosa pseudoharengus is an anadromous fish that migrates from marine to freshwaters to spawn. The early larval and juvenile forms are known to be planktivorous, where heavy feeding upon their preferred food source of large crustacean zooplankton often results in changes to composition and size structure within this trophic guild which in turn can result in shifts within the trophic spectrum and a classic trophic cascade. In this study of Lower Mill Pond, Brewster MA, we evaluated the feeding strategy of juvenile Alosa to determine whether juvenile alewife switches to feeding largely on cyanobacteria and whether cyanotoxins microcystin (MC) and β-methlyamino-L-alanine (BMAA) bioaccumulate in their muscle tissue. Within 15 - 30 days of their estimated spawning date, overexploitation of crustacean zooplankton resulted in a shift from planktivory to benthic detritivory for the majority of their life history, although this did not reduce their condition based on weight-length relationships (Log Wwt. = -5.503 + (3.101 × Log Length). Mean MC (0.003 μg

Evaluation of Size Structure in Freshwater Cyanobacterial Populations: Methods to Quantify Risk Associated with Changes in Biomass and Microcystin Concentrations

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j.urnal of Water Resource and Protection 2019年第6期11卷 810-829页

作者： nancy j. leland j.mes F. Haney Kristin Conte Karen Malkus-Benj.min Bryan Horsely Lim-Tex North Andover MA USA Department of Zoology University of New Hampshire Durham NH USA Manchester Water Works Manchester NH USA Town of Barnstable Barnstable MA USA Association to Preserve Cape Cod Dennis MA USA

Cyanobacterial populations in surface waters, including drinking water supplies and recreational waters, represent an ever present challenge for resource managers. As communities continuously respond to external and internal processes, dynamic profiles of composition, dominance, growth and toxigenicity emerge. In this study measures of size structure and biomass, quantified using light microscopy and fluorometry, were used to estimate microcystin concentrations through linear regression analysis. Toxigenic profiles using cyanobacterial biomass were developed for lakes dominated by Microcystis spp. and Dolichospermum spp., influenced by both genus-specific pigment concentrations as well as microcystin concentrations. Community composition (Log %MIC) and biomass were used to describe microcystin concentrations in mixed assemblages, where composition was the first input variable. The accessory photopigment phycocyanin was used to describe the linear relationship between the daily growth and net microcystin production rates in the bloom-forming Microcystis spp. samples, suggesting that this size-fractionated sample may provide indications of potential toxigenicity in the whole lake water sample. Future investigations using fluorometric evaluation of cyanobacterial populations could provide additional applications and metrics for use by resource managers to quantify risk association with elevated cyanotoxin concentrations.

关键词： Microcystis Dolichospermum Phycocyanin Microcystins Growth Rates

Isolation of Picocyanobacteria (Order Synechococcales) and Occurrence of the Cyanotoxin Anatoxin-A in a Shallow Mesotrophic Pond

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j.urnal of Water Resource and Protection 2023年第9期15卷 299-314页

作者： nancy j. leland Kimberley Crocker Pearson Marty K. Burke j.ffrey T. Miller Alison Watts j.mes F. Haney Department of Biological Sciences University of New Hampshire Center for Freshwater Biology and Ecotoxicology Durham New Hampshire USA Lim-Tex North Andover Massachusetts USA Brewster Natural Resources Advisory Commission Brewster Massachusetts USA Brewster Ponds Coalition Brewster Massachusetts USA Department of Civil and Environmental Engineering University of New Hampshire College of Engineering and Physical Sciences Durham New Hampshire USA

We have verified the use of a serial filtration method to isolate picocyanobacteria for analysis. We used eDNA metabarcoding to confirm the picocyanobacteria as members of the Order Synechococcales, Genus Cyanobium, specifically Cyanobium 6307. Fluorometric analysis using accessory pigments phycocyanin and phycoerythrin described periods of excess biomass, where the net growth rate model confirmed these conditions. The total anatoxin-a concentrations in the picocyanobacterial sample ranged from 0.0074 - 6.41 μg·L-1 representing a 40-fold difference over the entire sampling season. Sampling frequency of every three days appeared to be an important factor in capturing these changes in anatoxin-a concentration. During a period of excess biomass, we were able to establish a linear correlation between cyanobacterial biomass and Anatoxin-a concentrations.

关键词： Picocyanobacteria Anatoxin-a eDNA Phycocyanin Phycoerythrin

Diet variability of snappers(Teleostei:Lutj.nidae)in a bay-to-reef ecosystem of the Mexican Caribbean

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Water Biology and Security 2024年第1期3卷 53-59页

作者： Leon Felipe Martínez-j.arez j.an j.Schmitter-Soto nancy Cabanillas-Teran Norman Mercado-Silva El Colegio de la Frontera Sur 77014ChetumalQuintana RooMexico Centro de Investigacion en Biodiversidad y Conservacion Universidad Autonoma del Estado de Morelos62209CuernavacaMorelosMexico

Fishes use environmental resources *** ontogenic movements among coastal habitats lead to diverse *** investigated the diets of seven snapper species(Lutj.nus apodus,***,***,***,***,***,and Ocyurus chrysurus)in three interconnected coastal environments in the western Caribbean:Río Huach channel,Chetumal/Corozal bay,and the adj.cent Xcalak reef *** three encompass all habitats used by the seven species in the study *** diets were mostly composed of fish and crustaceans,but dominance of either group varied among the studied habitats;for example,fish were the main prey for *** from the reef lagoon zone,but second in the *** are piscivorous-invertivorous mesopredators;the species that relied the most on fishes were *** and ***,whereas *** preferred *** content results revealed a high degree of dietary overlap among *** findings suggested a tradeoff in relative weight between fish and crustaceans as the main food source of snappers at these connected areas,supporting the hypothesis of niche *** results can be used as a baseline to further our understanding of the ecology and differences in resource use by snapper species in an area undergoing important anthropogenic changes.

关键词： Resource partitioning Chetumal/Corozal bay Quintana Roo Trophic ecology

Isolation of Picocyanobacteria (Order Synechococcales ) and Occurrence of the Cyanotoxin Anatoxin-A in a Shallow Mesotrophic Pond

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Effects of Gamma Irradiation for Sterilization on Aqueous Dispersions of Length Sorted Carbon Nanotubes

j.urnal of Water Resource and Protection（水资源与保护） 2023年第6期

作者： nancy j. leland Kimberley Crocker Pearson Marty K. Burke j.ffrey T. Miller Alison Watts j.mes F. Haney

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Nano Research 2011年第4期4卷 393-404页

作者： j.ffrey A. Fagan nancy j. Lin Rolf Zeisler Angela R. Hight Walker Polymers Division National Institute of Standards and Technology Gaithersburg MD 20899 USA Analytical Chemistry Division National Institute of Standards and Technology Gaithersburg MD 20899 USA Optical Technology Division. National Institute of Standards and Technology Gaithersburg MD 20899. USA

There is currently great interest in the potential use of carbon nanotubes as delivery vessels for nanotherapeutics and other medical applications. However, no data are available on the effects of sterilization methods on the properties of nanotube dispersions, the form in which most medical applications will be processed. Here we show the effects of gamma irradiation from a 60Co source on the dispersion and optical properties of single-wall carbon nanotubes in aqueous dispersion. Samples of different length-refined populations were sealed in ampoules and exposed to a dose of approximately 28 kGy, a level sufficient to ensure sterility of the dispersions. In contrast to literature results for solid-phase nanotube samples, the effects of gamma irradiation on the dispersion and optical properties of the nanotube samples were found to be minimal. Based on these results, gamma irradiation appears sufficiently non-destructive to be industrially useful for the sterilization of nanotube dispersions.

关键词： Nanotube single-wall nanotube (SWNT) single-wall carbon nanotube (SWCNT) gamma irradiation sterilization dispersion

SimMarket research student playbook / nancy j. Nentl, Craig Miller.

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SimMarket research student playbook / Nancy J. Nentl, Craig ...

Development and Preliminary Validation of the Older Adult Service Usage Assessment

2003年

作者： nancy j. Nentl Craig Miller.

来源：畅想之星图书光盘版（南... 评论

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Advances in Aging Research 2017年第4期6卷 61-72页

作者： nancy j. Karlin School of Psychological Sciences University of Northern Colorado Greeley CO USA

This study provides information on the development and factor scaling, validity, and reliability of a newly developed community service utilization measure (Older Adult Service Usage Assessment-OASUA). Analyzes indicate the OASUA can be used to assess current perceived community service use and satisfaction, as well as providing an indication for future service use and potential service needs with older persons. Additional data collection sites should be identified and a broader sample obtained so as to confirm the psychometric properties of the instrument in conj.nction with further development of the OASUA.

关键词： Older Adult Home and Community-Based Services Rural Aging

Gastric cancer in Alaska Native people: A cancer health disparity

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World j.urnal of Gastroenterology 2018年第25期24卷 2722-2732页

作者： Holly A Martinson nancy j.Shelby Steven R Alberts Matthew j.Olnes WWAMI School of Medical Education University of Alaska Anchorage Department of Oncology Mayo Clinic Cancer Center Hematology and Medical Oncology Department Alaska Native Medical Center

AIM To evaluate recent trends in gastric cancer incidence, response to treatment, and overall survival among Alaska Native(AN) people. METHODS A retrospective analysis of the Alaska Native Medical Center patient database was performed. Patient history, clinical, pathological, response to treatment and patient outcomes were collected from one-hundred and thirty-two AN gastric cancer patients. The Surveillance, Epidemiology and End Result database 18 was used to collect comparison United States non-Hispanic White(NHW) and AN gastric cancer patient data between *** AN gastric cancer patients have a higher incidence rate, a poorer overall survival, and are diagnosed at a significantly younger age compared to NHW patients. AN patients differ from NHW patients in greater prevalence of non-cardia, diffuse subtype, and signet ring cell carcinomas. AN females were more likely to be diagnosed with later stage cancer, stage IV, compared to AN males. Diminished overall survival was observed among AN patients with increasing stage, O+ blood type, < 15 lymph nodes examined at resection, and no treatment. This study is the first report detailing the clinicopathologic features of gastric cancer in AN people with outcome *** Our findings confirm the importance of early detection, treatment, and surgical resection for optimizing AN patient outcomes. Further research on early detection markers are warranted.

关键词： Alaska Native gastric cancer Helicobacter pylori gender health disparities