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1.
Sci Rep ; 14(1): 4357, 2024 02 22.
Article in English | MEDLINE | ID: mdl-38388645

ABSTRACT

Monitoring pathogen circulation in wildlife sentinel populations can help to understand and predict the spread of disease at the wildlife-livestock-human interface. Immobile young provide a useful target population for disease surveillance, since they can be easily captured for sampling and their levels of antibodies against infectious agents can provide an index of localized circulation. However, early-life immune responses include both maternally-derived antibodies and antibodies resulting from exposure to pathogens, and disentangling these two processes requires understanding their individual dynamics. We conducted an egg-swapping experiment in an urban-nesting sentinel seabird, the yellow-legged gull, and measured antibody levels against three pathogens of interest (avian influenza virus AIV, Toxoplasma gondii TOX, and infectious bronchitis virus IBV) across various life stages, throughout chick growth, and between nestlings raised by biological or non-biological parents. We found that levels of background circulation differed among pathogens, with AIV antibodies widely present across all life stages, TOX antibodies rarer, and IBV antibodies absent. Antibody titers declined steadily from adult through egg, nestling, and chick stages. For the two circulating pathogens, maternal antibodies declined exponentially after hatching at similar rates, but the rate of linear increase due to environmental exposure was significantly higher in the more prevalent pathogen (AIV). Differences in nestling antibody levels due to parental effects also persisted longer for AIV (25 days, vs. 14 days for TOX). Our results suggest that yellow-legged gulls can be a useful sentinel population of locally transmitted infectious agents, provided that chicks are sampled at ages when environmental exposure outweighs maternal effects.


Subject(s)
Charadriiformes , Influenza A virus , Influenza in Birds , Animals , Humans , Antibodies, Viral , Chickens
2.
Development ; 150(16)2023 08 15.
Article in English | MEDLINE | ID: mdl-37526609

ABSTRACT

Developmentally programmed polyploidy (whole-genome duplication) of cardiomyocytes is common across evolution. Functions of such polyploidy are essentially unknown. Here, in both Drosophila larvae and human organ donors, we reveal distinct polyploidy levels in cardiac organ chambers. In Drosophila, differential growth and cell cycle signal sensitivity leads the heart chamber to reach a higher ploidy/cell size relative to the aorta chamber. Cardiac ploidy-reduced animals exhibit reduced heart chamber size, stroke volume and cardiac output, and acceleration of circulating hemocytes. These Drosophila phenotypes mimic human cardiomyopathies. Our results identify productive and likely conserved roles for polyploidy in cardiac chambers and suggest that precise ploidy levels sculpt many developing tissues. These findings of productive cardiomyocyte polyploidy impact efforts to block developmental polyploidy to improve heart injury recovery.


Subject(s)
Drosophila , Myocytes, Cardiac , Animals , Humans , Polyploidy , Ploidies , Cell Cycle
3.
Nutr Metab Insights ; 16: 11786388231151355, 2023.
Article in English | MEDLINE | ID: mdl-37197267

ABSTRACT

Background: Milk contains essential nutrients that help can improve the growth and development of adolescent girls. Objectives: The study determined the effect of milk consumption on the nutritional status of schoolgirls ages 10 to 12 years old in Magdalena, Laguna, Philippines. Methodology: A quasi-experimental study design was used to determine the impact of daily consumption of 200 ml buffalo milk on the prevalence of undernutrition among the 57 schoolgirl participants before and after 160 days. One sample t-test and paired t-test were used to compare the actual and expected total increment and monthly changes in the height and body mass index (BMI) of the participants, while a one-way analysis of variance was used to compare the actual total changes in height and BMI by age. Factors that are correlated with these measurements were identified based on Spearman's correlation coefficients. Results: The percentage of stunting (31.6%-22.8%) and thinness (21.1%-15.8%) decreased after the milk feeding. Significant differences were observed in the means of total actual and expected changes in height (P < .00) and BMI (P < .00). While there were significant differences in the means of actual and expected monthly changes in height every month, this was only observed in the first 2 months for BMI. Only the mean actual changes in height had significant differences when compared by age (P = .04). Lastly, the age and education of the father were found to be correlated with the height of the schoolgirls. Conclusion: Buffalo milk consumption can improve the growth outcomes of schoolgirls.

4.
Med Decis Making ; 43(6): 631-641, 2023 08.
Article in English | MEDLINE | ID: mdl-37199414

ABSTRACT

BACKGROUND: Rates of advance directive (AD) completion in the United Kingdom are lower than in the United States and other western European countries, which is especially concerning in light of the COVID-19 pandemic. UK residents typically complete an advance decision to refuse care (ADRT), whereas US versions of ADs present a more neutral choice between comfort-oriented or life-prolonging care. The purpose of this study is to test whether this framing affects decision making for end-of-life care and if this is affected by exposure to information about the COVID-19 pandemic. METHODS: In an online experiment, 801 UK-based respondents were randomly allocated to document their preferences for end-of-life care in a 2 (US AD or UK ADRT) by 2 (presence or absence of COVID-19 prime) between-subjects factorial design. RESULTS: Most (74.8%) of participants across all conditions chose comfort-oriented care. However, framing comfort care as a refusal of treatment made respondents significantly less likely to choose it (65.4% v. 84.1%, P < 0.001). This effect was exacerbated by priming participants to think about COVID-19: those completing an ADRT were significantly more likely to choose life-prolonging care when exposed to the COVID-19 prime (39.8% v. 29.6%, P = 0.032). Subgroup analyses revealed these effects differed by age, with older participants' choices influenced more by COVID-19 while younger participants were more affected by the AD framing. CONCLUSIONS: The UK ADRT significantly reduced the proportion of participants choosing comfort-oriented care, an effect that was heightened in the presence of information about COVID-19. This suggests the current way end-of-life care wishes are documented in the United Kingdom could affect people's choices in a way that does not align with their preferences, especially in the context of the COVID-19 pandemic. HIGHLIGHTS: Participants completing an AD framed as an advance decision to refuse treatment were significantly less likely to choose comfort-oriented care than participants completing an AD with a neutral choice between comfort-oriented and life-prolonging care.Exposure to a COVID-19 prime had an interactive effect on documented preferences in the refusal of treatment condition, with these participants even less likely to choose comfort-oriented care.Policy makers and organizations that design templates for advance care planning, particularly in the time of the COVID-19 pandemic, should be aware how the framing of these forms can influence decisions.


Subject(s)
COVID-19 , Patient Comfort , Humans , United States , Pandemics , Death , Treatment Refusal
6.
bioRxiv ; 2023 Feb 11.
Article in English | MEDLINE | ID: mdl-36798187

ABSTRACT

Developmentally programmed polyploidy (whole-genome-duplication) of cardiomyocytes is common across evolution. Functions of such polyploidy are essentially unknown. Here, we reveal roles for precise polyploidy levels in cardiac tissue. We highlight a conserved asymmetry in polyploidy level between cardiac chambers in Drosophila larvae and humans. In Drosophila , differential Insulin Receptor (InR) sensitivity leads the heart chamber to reach a higher ploidy/cell size relative to the aorta chamber. Cardiac ploidy-reduced animals exhibit reduced heart chamber size, stroke volume, cardiac output, and acceleration of circulating hemocytes. These Drosophila phenotypes mimic systemic human heart failure. Using human donor hearts, we reveal asymmetry in nuclear volume (ploidy) and insulin signaling between the left ventricle and atrium. Our results identify productive and likely conserved roles for polyploidy in cardiac chambers and suggest precise ploidy levels sculpt many developing tissues. These findings of productive cardiomyocyte polyploidy impact efforts to block developmental polyploidy to improve heart injury recovery.

7.
Mov Ecol ; 11(1): 1, 2023 Jan 04.
Article in English | MEDLINE | ID: mdl-36600306

ABSTRACT

Telemetry is a powerful and indispensable tool for evaluating wildlife movement and distribution patterns, particularly in systems where opportunities for direct observation are limited. However, the effort and expense required to track individuals often results in small sample sizes, which can lead to biased results if the sample of tracked individuals does not fully capture spatial, temporal, and individual variability within the target population. To better understand the influence of sampling design on results of automated radio telemetry studies, we conducted a retrospective power analysis of very high frequency (VHF) radio telemetry data from the Motus Wildlife Tracking System for two species of birds along the United States Atlantic coast: a shorebird, the piping plover (Charadrius melodus), and a nearshore seabird, the common tern (Sterna hirundo). We found that ~ 100-150 tracked individuals were required to identify 90% of locations known to be used by the tracked population, with 40-50 additional individuals required to include 95% of used locations. For any number of individuals, the percentage of stations included in the sample was higher for common terns than for piping plovers when tags were deployed within a single site and year. Percentages of stations included increased for piping plovers when birds were tagged over multiple sites and, to a lesser extent, years, and increased with average length of the tracking period. The probability that any given receiver station used by the population would be included in a subsample increased with the number of birds tracked, station proximity to a migratory stopover or staging site, number of receiving antennas per station, and percentage of the tracked population present. Our results provide general guidance for the number and distribution of tagged birds required to obtain representative VHF telemetry data, while also highlighting the importance of accounting for station network configuration and species-specific differences in behavior when designing automated radio telemetry studies to address specific research questions. Our results have broad applications to remotely track movements of small-bodied migratory wildlife in inaccessible habitats, including predicting and monitoring effects of offshore wind energy development.

8.
Conserv Physiol ; 10(1): coac064, 2022.
Article in English | MEDLINE | ID: mdl-36159741

ABSTRACT

The northern Gulf of Mexico supports a diverse community of nearshore seabirds during both breeding and nonbreeding periods of the annual cycle and is also a highly industrialized marine ecosystem with substantial levels of oil and gas development particularly in the west and central regions. Stakeholders in the region often assess risk to species of interest based on these differing levels of development. We collected blood samples from 81 adult and 35 chick eastern brown pelicans (Pelecanus occidentalis carolinensis) from 10 colonies across the northern Gulf of Mexico and used these to establish baseline values for hematology and blood biochemistry. We assessed the potential influence of body condition, sex and home range size on hematology and blood biochemistry. We also assessed potential influences of oil and gas activity by considering differing levels of oil and gas development that occur regionally throughout the study area. Although blood analyte concentrations of adults and chicks were often associated with these regional differences, the pattern we observed was not entirely consistent with the differing levels of oil and gas activity across the Gulf, suggesting that regional levels of oil and gas activity around breeding sites may not be the primary drivers of hematology and blood biochemistry. We note that baseline values or reference intervals are not available for other nearshore seabirds that breed in the northern Gulf. Given that exposure and risk may differ among this suite of species based on diet, foraging strategies and life history strategies, similar assessments and monitoring may be warranted.

10.
Cogn Res Princ Implic ; 7(1): 51, 2022 06 17.
Article in English | MEDLINE | ID: mdl-35713818

ABSTRACT

The world population is getting older and, as a result, the number of older victims of crime is expected to increase. It is therefore essential to understand how ageing affects eyewitness identification, so procedures can be developed that enable victims of crime of all ages to provide evidence as accurately and reliably as possible. In criminal investigations, witnesses often provide a description of the perpetrator of the crime before later making an identification. While describing the perpetrator prior to making a lineup identification can have a detrimental effect on identification in younger adults, referred to as verbal overshadowing, it is unclear whether older adults are affected in the same way. Our study compared lineup identification of a group of young adults and a group of older adults using the procedure that has consistently revealed verbal overshadowing in young adults. Participants watched a video of a mock crime. Following a 20-min filled delay, they either described the perpetrator or completed a control task. Immediately afterwards, they identified the perpetrator from a lineup, or indicated that the perpetrator was not present, and rated their confidence. We found that describing the perpetrator decreased subsequent correct identification of the perpetrator in both young and older adults. This effect of verbal overshadowing was not explained by a change in discrimination but was consistent with participants adopting a more conservative criterion. Confidence and response time were both found to predict identification accuracy for young and older groups, particularly in the control condition.


Subject(s)
Criminals , Recognition, Psychology , Aged , Aging , Crime , Humans , Mental Processes , Young Adult
11.
Front Psychiatry ; 13: 797427, 2022.
Article in English | MEDLINE | ID: mdl-35370806

ABSTRACT

Introduction: Establishing structured peer support in mental health, particularly for people with schizophrenia, as a psychosocial intervention is early in low and middle-income countries like India. Before implementing and understanding the effectiveness of peer support service and which mode of peer support delivery will be suitable for our culture, our study aimed to understand if peer support would be accepted by the different participants like persons with schizophrenia, caregivers and mental health professionals in a tertiary care center in Chennai, India. Methods: The study was conducted at the outpatient department (OPD) of a tertiary psychiatric care facility in Chennai, India. A cross-sectional study method was used. Consecutive persons diagnosed with schizophrenia and caregivers of persons with schizophrenia, who attended the outpatient department, and mental health professionals within and outside the facility who met the inclusion and exclusion criteria participated in the study. A structured questionnaire purposefully developed for the study was administered to the different study participants. Descriptive statistics were used to analyze the data. Categorical variables were expressed as frequency and percentages, while the continuous variables were expressed as mean and standard deviation. Results: A total of 155 participants (52 persons with schizophrenia, 50 caregivers and 53 mental health professionals) completed the survey. The majority of the participants (90.4% of persons with schizophrenia, 86% caregivers and all mental health professionals) welcomed peer support interventions. The participants wanted peers to help persons with schizophrenia achieve personal goals to enhance their mental health and day to day living with an emphasis on independent living and interpersonal and social relationships and help them achieve medication and treatment-related goals toward recovery. Understanding the role of a peer support volunteer and transitioning from a "person with schizophrenia" to a "peer support volunteer" by persons with schizophrenia was thought most challenging. Conclusion: The results highlight the potential acceptability of peer support across several stakeholders in the care of schizophrenia in a low and middle-income country context. The results may guide the implementation of a peer support volunteer programme as an essential mechanism of delivering psychosocial interventions for persons with schizophrenia.

12.
J Pediatr Nurs ; 59: 158-163, 2021.
Article in English | MEDLINE | ID: mdl-33894543

ABSTRACT

BACKGROUND: Education is the most essential component for effective asthma control and is endorsed by guidelines worldwide. However, multiple caregivers are often jointly involved in child care, and educating them is often a challenging task. This study determines the effectiveness of a web-based asthma education program in enhancing knowledge, attitude and practice of caregivers and reducing unscheduled hospital visits of children for asthma. METHODS: A two-arm, randomized controlled trial was carried out between November 2018 and December 2019. Child-parent dyads were recruited when the children (4-11 years of age) were admitted due to asthma exacerbations. A nurse-led web-based home asthma education program was developed and implemented before discharge. Outcomes included parents' knowledge, attitude and practice regarding asthma and frequency of unscheduled visits and readmissions in children. RESULTS: 112 child-parent dyads were enrolled. The parents' knowledge, attitude and practice and the number of unscheduled visits of the children were found to be significantly different between two groups at different time points (Ps < 0.001) with a large effect size (Cohen's d > 0.8). CONCLUSION: This intervention was shown to be an effective strategy to educate caregivers who are jointly involved in their child's asthma control after discharge from hospital. TRIAL REGISTRATION: The Chinese Clinical Trial Registry, World Health Organization (ChiCTR1800019706).


Subject(s)
Asthma , Nurse's Role , Asthma/prevention & control , Caregivers , Humans , Internet , Patient Discharge
13.
Am J Surg ; 222(1): 139-144, 2021 07.
Article in English | MEDLINE | ID: mdl-33279170

ABSTRACT

BACKGROUND: Pancreatic cancer is a leading cause of financial insolvency and cancer related deaths in the United States. The risk of catastrophic health expenditure (CHE) was calculated for patients undergoing pancreatic resection at an academic institution. METHODS: Patients who underwent pancreatic resection between 2013 and 2017 were identified through an institutional cancer registry. A CHE was an out-of-pocket payment (OOP) > 10% of the estimated median household income. RESULTS: 319 patients met inclusion criteria. Hospital median charge was $76,700. 99% of patients had insurance and hospital bill adjustments. As a result, 61% (n = 193) made no OOP. Only 3 patients risked CHE. For all tumors combined there were no differences in survival outcomes by OOP. CONCLUSION: This is the first study to use institutional financial data to calculate CHE risk for pancreatic resection patients. Insurance adjustments to hospital charges that accompany health insurance and voluntary hospital adjustments for the uninsured protect patients against CHE.


Subject(s)
Financial Stress/epidemiology , Financing, Personal/statistics & numerical data , Health Expenditures/statistics & numerical data , Insurance, Health/economics , Pancreatic Neoplasms/surgery , Academic Medical Centers/economics , Academic Medical Centers/statistics & numerical data , Aged , Female , Financial Stress/prevention & control , Humans , Insurance, Health/statistics & numerical data , Kaplan-Meier Estimate , Male , Middle Aged , Pancreatectomy/economics , Pancreatectomy/statistics & numerical data , Pancreatic Neoplasms/economics , Pancreatic Neoplasms/mortality , Registries/statistics & numerical data , Retrospective Studies , Risk Assessment/statistics & numerical data , Socioeconomic Factors , Survival Rate , United States/epidemiology
14.
Ann Glob Health ; 86(1): 121, 2020 09 22.
Article in English | MEDLINE | ID: mdl-33024707

ABSTRACT

Background: Community Health Education (CHE) programs have been shown to be effective in relieving the burden on healthcare systems in Sub-Saharan Africa. Objective: This project aimed to determine the baseline level of health literacy, behavioral practices, and accessibility to resources in a set of 16 informal settlements located around Lagos, Nigeria in order to identify topics that should be emphasized in a new teaching curriculum directed at local Community Health Educators. Methods: In June of 2017, a unique cross-sectional survey composed of 37 questions was conducted in informal settlements around Lagos. Sites selected were areas in which future CHE trainings were planned to take place and survey participants were chosen by trained community health educators based on convenience sampling with snowball effect. Survey questions included both multiple-choice and open-ended questions and were asked in the local language. We collected demographic information and assessed health literacy, health behaviors, and community practices. Results were analyzed using descriptive statistics to assess for differences between demographic groups. Findings: Our survey collected 348 total responses. Respondents displayed a high level of knowledge regarding the benefits of hand washing (97.1%) and childhood immunizations (81.0%). Knowledge around infectious diseases and reproductive health was lower, including a large proportion of people (50%) incorrectly indicating that HIV could be spread through a mosquito bite. Malaria was reported to be the most prevalent disease affecting both adults (40.0%) and children (58.3%). Health access was limited, with most people not reporting access to a nearby health center (55.8%). Conclusions: Areas of knowledge that should be emphasized in future versions of CHE training curricula include infectious diseases, reproductive health, and reinforcement of the importance of sanitation and clean water. The curriculum should address the reality of limited health access and develop strategies to improve this.


Subject(s)
Health Education , Malaria , Adult , Child , Cross-Sectional Studies , Health Knowledge, Attitudes, Practice , Humans , Nigeria , Perception
15.
Elife ; 92020 10 14.
Article in English | MEDLINE | ID: mdl-33051002

ABSTRACT

Multiple nuclei sharing a common cytoplasm are found in diverse tissues, organisms, and diseases. Yet, multinucleation remains a poorly understood biological property. Cytoplasm sharing invariably involves plasma membrane breaches. In contrast, we discovered cytoplasm sharing without membrane breaching in highly resorptive Drosophila rectal papillae. During a six-hour developmental window, 100 individual papillar cells assemble a multinucleate cytoplasm, allowing passage of proteins of at least 62 kDa throughout papillar tissue. Papillar cytoplasm sharing does not employ canonical mechanisms such as incomplete cytokinesis or muscle fusion pore regulators. Instead, sharing requires gap junction proteins (normally associated with transport of molecules < 1 kDa), which are positioned by membrane remodeling GTPases. Our work reveals a new role for apical membrane remodeling in converting a multicellular epithelium into a giant multinucleate cytoplasm.


Most cells are self-contained ­ they have a cell membrane that delimits and therefore defines the cell, separating it from other cells and from its environment. But sometimes several cells interconnect and form collectives so they can pool their internal resources. Some of the best-known examples of this happen in animal muscle cells and in the placenta of mammals. These cell collectives share their cytoplasm ­ the fluid within the cell membrane that contains the cell organelles ­ in one of two ways. Cells can either remain linked instead of breaking away when they divide, or they can fuse their membranes with those of their neighbors. Working out how cells link to their neighbors is difficult when so few examples of cytoplasm sharing are available for study. One way to tackle this is to try and find undiscovered cell collectives in an animal that is already heavily studied in the lab, such as the fruit fly Drosophila melanogaster. Peterson et al. used a genetic system that randomly labels each cell of the developing fly with one of three fluorescent proteins. These proteins are big and should not move between cells unless they are sharing their cytoplasm. This means that any cell containing two or more different colors of fluorescent protein must be connected to at least one of its neighbors. The experiment revealed that the cells of the fruit fly rectum share their cytoplasm in a way never seen before. This sharing occurs at a consistent point in the development of the fruit fly and uses a different set of genes to those used by interconnecting cells in mammal muscles and placenta. These genes produce proteins that reshape the membranes of the cells and fit them with gap junctions ­ tiny pores that cross from one membrane to the next, allowing the passage of very small molecules. In this case, the gap junctions allowed the cells to share molecules much larger than seen before. The result is a giant cell membrane containing the cytoplasm and organelles of more than a hundred individual cells. These findings expand scientists' understanding of how cells in a tissue can share cytoplasm and resources. They also introduce a new tissue in the fruit fly that can be used in future studies of cytoplasm sharing. Relatives of fruit flies, including fruit pests and mosquitos, have similar cell structure to the fruit fly, which means that further investigations using this system could result in advances in agriculture or human health.


Subject(s)
Cell Membrane/metabolism , Cytoplasm/metabolism , Drosophila melanogaster/embryology , Intestines/embryology , Animals , Connexins/metabolism , Crosses, Genetic , Cytokinesis , Cytosol/metabolism , Epithelium/metabolism , GTP Phosphohydrolases/chemistry , Gap Junctions , Genotype , Microscopy, Electron, Transmission , Signal Transduction
16.
Mov Ecol ; 7: 30, 2019.
Article in English | MEDLINE | ID: mdl-31673358

ABSTRACT

BACKGROUND: Mobile organisms in marine environments are expected to modify their behavior in response to external stressors. Among environmental drivers of animal movement are long-term climatic indices influencing organism distribution and short-term meteorological events anticipated to alter acute movement behavior. However, few studies exist documenting the response of vagile species to meteorological anomalies in coastal and marine systems. METHODS: Here we examined the movements of Eastern brown pelicans (Pelecanus occidentalis carolinensis) in the South Atlantic Bight in response to the passage of three separate hurricane events in 2 years. Pelicans (n = 32) were tracked with GPS satellite transmitters from four colonies in coastal South Carolina, USA, for the entirety of at least one storm event. An Expectation Maximization binary Clustering algorithm was used to discretize pelican behavioral states, which were pooled into 'active' versus 'inactive' states. Multinomial logistic regression was used to assess behavioral state probabilities in relation to changes in barometric pressure and wind velocity. RESULTS: Individual pelicans were more likely to remain inactive during tropical cyclone passage compared to baseline conditions generally, although responses varied by hurricane. When inactive, pelicans tended to seek shelter using local geomorphological features along the coastline such as barrier islands and estuarine systems. CONCLUSIONS: Our telemetry data showed that large subtropical seabirds such as pelicans may mitigate risk associated with spatially-extensive meteorological events by decreasing daily movements. Sheltering may be related to changes in barometric pressure and wind velocity, and represents a strategy common to several other classes of marine vertebrate predators for increasing survival probabilities.

17.
Ecol Appl ; 29(5): e01919, 2019 07.
Article in English | MEDLINE | ID: mdl-31141283

ABSTRACT

Conservation of long-distance migratory species poses unique challenges. Migratory connectivity, that is, the extent to which groupings of individuals at breeding sites are maintained in wintering areas, is frequently used to evaluate population structure and assess use of key habitat areas. However, for species with complex or variable annual cycle movements, this traditional bimodal framework of migratory connectivity may be overly simplistic. Like many other waterfowl, sea ducks often travel to specific pre- and post-breeding sites outside their nesting and wintering areas to prepare for migration by feeding extensively and, in some cases, molting their flight feathers. These additional migrations may play a key role in population structure, but are not included in traditional models of migratory connectivity. Network analysis, which applies graph theory to assess linkages between discrete locations or entities, offers a powerful tool for quantitatively assessing the contributions of different sites used throughout the annual cycle to complex spatial networks. We collected satellite telemetry data on annual cycle movements of 672 individual sea ducks of five species from throughout eastern North America and the Great Lakes. From these data, we constructed a multi-species network model of migratory patterns and site use over the course of breeding, molting, wintering, and migratory staging. Our results highlight inter- and intra-specific differences in the patterns and complexity of annual cycle movement patterns, including the central importance of staging and molting sites in James Bay, the St. Lawrence River, and southern New England to multi-species annual cycle habitat linkages, and highlight the value of Long-tailed Ducks (Calengula haemalis) as an umbrella species to represent the movement patterns of multiple sea duck species. We also discuss potential applications of network migration models to conservation prioritization, identification of population units, and integrating different data streams.


Subject(s)
Ducks , Ecosystem , Animal Migration , Animals , Lakes , New England , Seasons
18.
Ecol Evol ; 9(5): 2346-2364, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30891185

ABSTRACT

Modeling organism distributions from survey data involves numerous statistical challenges, including accounting for zero-inflation, overdispersion, and selection and incorporation of environmental covariates. In environments with high spatial and temporal variability, addressing these challenges often requires numerous assumptions regarding organism distributions and their relationships to biophysical features. These assumptions may limit the resolution or accuracy of predictions resulting from survey-based distribution models. We propose an iterative modeling approach that incorporates a negative binomial hurdle, followed by modeling of the relationship of organism distribution and abundance to environmental covariates using generalized additive models (GAM) and generalized additive models for location, scale, and shape (GAMLSS). Our approach accounts for key features of survey data by separating binary (presence-absence) from count (abundance) data, separately modeling the mean and dispersion of count data, and incorporating selection of appropriate covariates and response functions from a suite of potential covariates while avoiding overfitting. We apply our modeling approach to surveys of sea duck abundance and distribution in Nantucket Sound (Massachusetts, USA), which has been proposed as a location for offshore wind energy development. Our model results highlight the importance of spatiotemporal variation in this system, as well as identifying key habitat features including distance to shore, sediment grain size, and seafloor topographic variation. Our work provides a powerful, flexible, and highly repeatable modeling framework with minimal assumptions that can be broadly applied to the modeling of survey data with high spatiotemporal variability. Applying GAMLSS models to the count portion of survey data allows us to incorporate potential overdispersion, which can dramatically affect model results in highly dynamic systems. Our approach is particularly relevant to systems in which little a priori knowledge is available regarding relationships between organism distributions and biophysical features, since it incorporates simultaneous selection of covariates and their functional relationships with organism responses.

19.
Sci Total Environ ; 648: 1031-1041, 2019 Jan 15.
Article in English | MEDLINE | ID: mdl-30340251

ABSTRACT

People altered the biophysical environment upon which they depend through the overexploitation of resources and growing waste generation. Action is urgently needed to return the resource economy within planetary boundaries and safeguard human well-being, by realising an increasingly closed-loop system that maintains values of materials and products within a sustainable circular economy. Innovative technologies and business models must be developed and implemented, requiring convincing "business cases" for industry and government; why should they be interested in adopting circular, resource recovery practices? Despite multi-dimensional challenges facing people and their environment, and the ability of resource recovery to contribute to restoring environment, society and economy, arguments for circular practices are often overly focused on economic aspects. Economic growth is not a panacea and this article supports the preparation of better arguments by presenting expert insights on 37 themes to consider for a resource recovery business case. The most important themes cover 1) Economic, social, environmental and technical value of resources and 2) Regulatory change; focusing business cases on these is likely to deliver positive impacts regarding all identified themes. The article synthesises the old "growth will solve it-" with a new "multi-dimensional challenges and solutions" paradigm, suggesting that resource recovery should support multi-dimensional growth to partly redistribute economic benefits to social and environmental values through the preservation of technical, functional value of materials and products. Writing successful business cases for resource recovery requires inter-disciplinary collaboration, and sustained effort to complete and translate business cases into measurable impacts through changed practices outside academia.

20.
PLoS One ; 13(1): e0190953, 2018.
Article in English | MEDLINE | ID: mdl-29329319

ABSTRACT

Rock salt represents a potential host rock formation for the final disposal of radioactive waste. The interactions between indigenous microorganisms and radionuclides, e.g. uranium, need to be investigated to better predict the influence of microorganisms on the safety assessment of the repository. Hence, the association process of uranium with two microorganisms isolated from rock salt was comparatively studied. Brachybacterium sp. G1, which was isolated from the German salt dome Gorleben, and Halobacterium noricense DSM15987T, were selected as examples of a moderately halophilic bacterium and an extremely halophilic archaeon, respectively. The microorganisms exhibited completely different association behaviors with uranium. While a pure biosorption process took place with Brachybacterium sp. G1 cells, a multistage association process occurred with the archaeon. In addition to batch experiments, in situ attenuated total reflection Fourier-transform infrared spectroscopy was applied to characterize the U(VI) interaction process. Biosorption was identified as the dominating process for Brachybacterium sp. G1 with this method. Carboxylic functionalities are the dominant interacting groups for the bacterium, whereas phosphoryl groups are also involved in U(VI) association by the archaeon H. noricense.


Subject(s)
Bacteria/metabolism , Halobacterium/metabolism , Uranium/metabolism , Bacteria/classification , Bacteria/growth & development , Halobacterium/classification , Halobacterium/growth & development , Microscopy, Electron, Scanning , Phylogeny , Radioactive Waste , Spectrometry, X-Ray Emission , Spectroscopy, Fourier Transform Infrared
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