77 research outputs found
Energetic Impacts of Passage Delays in Migrating Adult Atlantic Salmon
For any migratory organism, habitat connectivity is critical for population stability. Structures that impede movement between necessary habitats can be damaging to population persistence. In riverine systems, dams act as migratory barriers, altering ecosystems and delaying, injuring, or otherwise impairing migratory fish movement into essential habitat. Critically endangered Atlantic salmon (Salmo salar) populations in Maine have been on the decline since the 1800s. Because most Atlantic salmon rivers are now highly dammed systems, hydropower dams have been cited as causal to the decline in returning adult populations. Previous studies have demonstrated that Atlantic salmon experience substantial delays below dams while moving upstream, but current state of knowledge with respect to metabolic costs and fitness outcomes for delayed Atlantic salmon provides no clear quantification of risk associated with this delay. I sought to understand consequences of delay in the context of an increased thermal experience below dams. With my collaborators, I have documented that water temperatures below surface-release dams remain several degrees warmer throughout peak summer months than water temperatures in upstream sections of river. Thus, adult Atlantic salmon experiencing delays below dams will be subject to warmer thermal experiences than if they had moved rapidly to upstream sections of river. As ectotherms, ambient water temperatures directly impact physiological processes, but salmonids generally have a narrow optimum temperature range. As waters warm to outside that range, metabolic processes become more energetically costly. That excess energy use might manifest itself in reduced individual reproductive success, or in the case of Atlantic salmon, a decrease in population iteroparity rates. In Chapter 1, we quantified the energetic cost of dam-mediated delays of adult migrating Atlantic salmon using HOBO temperature loggers, temperature-logging radio tags, and a Distell Fish Fatmeter as a noninvasive surrogate for full-body energy estimation. On the Penobscot River and Kennebec Rivers of central Maine, we tagged fish, released them a short distance below the dams, and tracked their movements back upstream, taking a Fatmeter measurement first at tagging and then after ascending the fish way at the respective dams. We found that Atlantic salmon experienced delays of two to three weeks on average while attempting to pass dams on their respective rivers. I that time, these fish lost between 11.1 and 19.4% of their starting endogenous fat reserves. Using the temperature-logging radio tags, we documented the individual thermal experience of each study salmon and determined that the thermal experience did indeed predict fat loss. Our results suggest that dams cause delays, not only extending migration times but also exposing adult Atlantic salmon to warmer water temperatures, compounding energetic impacts of dams and depleting available energy reserves. In Chapter 2, we utilized a bioenergetic model to further understand energy allocation of migrating adult Atlantic salmon in the context of delays at dams and corresponding water temperatures. Atlantic salmon can survive after spawning to be iteroparous, engaging in multiple reproductive life cycles over the course of a lifetime. Iteroparity is thought to be important to the conservation of this federally endangered species through greater population recruitment but currently, repeat spawners in Maine populations have been nearly eliminated. We modeled five different Atlantic salmon spawning runs in five different hypothetical rivers with either zero, one, two, three, or four dams presenting as migration barriers causing delays and subjecting salmon to warmer water temperatures. The results of our model showed that as the number of dams on a river increased, the number of post-spawn surviving Atlantic salmon decreased. On the unimpeded river, 6.3% of the run survived after spawning but on a river with four dams, only 2.8% of the returning salmon run survived. We also found that the number of salmon able to complete the single reproductive event decreased and the number of salmon that died before spawning increased as dams were added to the modeled system. Our results from Chapter 2 suggest that rapid movement through warmer downstream sections of rivers to upstream, cooler waters is key to increasing iteroparity rates in spawning populations and overall reproductive success
Bringing traits back in the equation : A roadmap to understand species redistribution
Acknowledgments This research is a product of the BIOSHIFTS working group funded by the synthesis center (CESAB) of the French Foundation for Research on Biodiversity (FRB; www.fondationbiodiversite.fr) and the project FRAGSHIFTS funded by the Ministry of Ecological Transition (MTE), French Office for Biodiversity (OFB), and the French Foundation for Research on Biodiversity (FRB). We thank Holly Embke and two reviewers (including Tom Luhring) for their time and constructive comments that have improved the initial submission.Peer reviewe
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Provision of mental health services in resource-poor settings: a randomised trial comparing counselling with routine medical treatment in North Afghanistan (Mazar-e-Sharif)
<p>Abstract</p> <p>Background</p> <p>Psychosocial stress caused by war, ongoing conflict, lack of security, and restricted access to resources promotes mental suffering and diseases in many resource-poor countries. In an exemplary setting, the present study compares the efficacy of psychosocial counselling with routine pharmacological treatment in a randomised trial in Mazar-e-Sharif (Afghanistan).</p> <p>Methods</p> <p>Help seeking Afghan women (N = 61), who were diagnosed with mental health symptoms by local physicians either received routine medical treatment<b/>(treatment as usual) or psychosocial counselling (5-8 sessions) following a specifically developed manualised treatment protocol. Primary outcome measures were symptoms of depression and anxiety assessed before treatment and at follow-up using the Hopkins Symptom Checklist and the Mini-International Neuropsychiatric Interview. Secondary outcome measures were psychosocial stressors and coping mechanisms.</p> <p>Results</p> <p>At 3-month follow-up, psychosocial counselling patients showed high improvements with respect to the severity of symptoms of depression and anxiety. In addition, they reported a reduction of psychosocial stressors and showed an enhancement of coping strategies. At the same time, the severity of symptoms, the quantity of psychosocial stressors and coping mechanisms did not improve in patients receiving routine medical treatment.</p> <p>Conclusion</p> <p>These results indicate that psychosocial counselling can be an effective treatment for mental illnesses even for those living in ongoing unsafe environments.</p> <p>Trial registration</p> <p><a href="http://www.clinicaltrials.gov/ct2/show/NCT01155687">NCT01155687</a></p
Introducing a unique animal ID and digital life history museum for wildlife metadata
Funding: C.R. acknowledges funding from the Gordon and Betty Moore Foundation (GBMF9881) and the National Geographic Society (NGS-82515R-20). G.B., R.K., S.C.D. and D.E.-S. acknowledge funding from NASA. A.S. and F.I. acknowledge support from the European Commission through the Horizon 2020 Marie Skłodowska-Curie Actions Individual Fellowships (grant no. 101027534 and no. 101107666, respectively). S.C.D. acknowledges funding from NASA Ecological Forecasting Program Grant 80NSSC21K1182. A.M.M.S. was supported by an ARC DP DP210103091. This project is funded in part by the Gordon and Betty Moore Foundation through Grant GBMF10539 to M.W., as well as the Academy for the Protection of Zoo Animals and Wildlife e.V., Germany.1. Over the past five decades, a large number of wild animals have been individually identified by various observation systems and/or temporary tracking methods, providing unparalleled insights into their lives over both time and space. However, so far there is no comprehensive record of uniquely individually identified animals nor where their data and metadata are stored, for example photos, physiological and genetic samples, disease screens, information on social relationships. 2. Databases currently do not offer unique identifiers for living, individual wild animals, similar to the permanent ID labelling for deceased museum specimens. 3. To address this problem, we introduce two new concepts: (1) a globally unique animal ID (UAID) available to define uniquely and individually identified animals archived in any database, including metadata archived at the time of publication; and (2) the digital ‘home’ for UAIDs, the Movebank Life History Museum (MoMu), storing and linking metadata, media, communications and other files associated with animals individually identified in the wild. MoMu will ensure that metadata are available for future generations, allowing permanent linkages to information in other databases. 4. MoMu allows researchers to collect and store photos, behavioural records, genome data and/or resightings of UAIDed animals, encompassing information not easily included in structured datasets supported by existing databases. Metadata is uploaded through the Animal Tracker app, the MoMu website, by email from registered users or through an Application Programming Interface (API) from any database. Initially, records can be stored in a temporary folder similar to a field drawer, as naturalists routinely do. Later, researchers and specialists can curate these materials for individual animals, manage the secure sharing of sensitive information and, where appropriate, publish individual life histories with DOIs. The storage of such synthesized lifetime stories of wild animals under a UAID (unique identifier or ‘animal passport’) will support basic science, conservation efforts and public participation.Peer reviewe
Abbott and Bacon Districts: Education Finances During the Great Recession
In the State of New Jersey, any child between the age of five and eighteen has the constitutional right to a thorough and efficient education. The State of New Jersey also has one of the country's most rigid policies regarding a balanced budget come fiscal end. When state and local revenues took a big hit in the most recent recession, officials had to make tough decisions about education spending. This paper exploits rich panel data and trend-shift analysis to analyze how school finances in the Abbott and Bacon School Districts, as well as the high-poverty districts in general, were affected during the Great Recession and the American Recovery and Reinvestment Act (ARRA) federal stimulus period. For these groups of districts, the debate over the meaning of thorough and efficient has become a perennial courtroom discussion. Our analysis shows downward shifts in revenue and expenditure per pupil during the post-recession era in all three groups of districts. However, the Abbott Districts showed the sharpest declines in both revenue and expenditure relative to preexisting trends. Of importance, the Abbott Districts were the only group in our analysis to show statistically significant negative shifts in instructional expenditure (the expenditure category most closely related to student learning), even with the federal stimulus. Declines in noninstructional categories were also the most prominent in the Abbott Districts. With comparably less declines in state and federal aid, the Bacon Districts maintained spending across the board at higher levels than the other groups. Given the unique role of the Abbott and Bacon Districts in the history of New Jersey education policy, the findings of this paper contribute valuable insight regarding the experience of these high-poverty districts during recessions
Prion Seeding Activities of Mouse Scrapie Strains with Divergent PrPSc Protease Sensitivities and Amyloid Plaque Content Using RT-QuIC and eQuIC
Different transmissible spongiform encephalopathy (TSE)-associated forms of prion protein (e.g. PrPSc) can vary markedly in ultrastructure and biochemical characteristics, but each is propagated in the host. PrPSc propagation involves conversion from its normal isoform, PrPC, by a seeded or templated polymerization mechanism. Such a mechanism is also the basis of the RT-QuIC and eQuIC prion assays which use recombinant PrP (rPrPSen) as a substrate. These ultrasensitive detection assays have been developed for TSE prions of several host species and sample tissues, but not for murine models which are central to TSE pathogenesis research. Here we have adapted RT-QuIC and eQuIC to various murine prions and evaluated how seeding activity depends on glycophosphatidylinositol (GPI) anchoring and the abundance of amyloid plaques and protease-resistant PrPSc (PrPRes). Scrapie brain dilutions up to 10-8 and 10-13 were detected by RT-QuIC and eQuIC, respectively. Comparisons of scrapie-affected wild-type mice and transgenic mice expressing GPI anchorless PrP showed that, although similar concentrations of seeding activity accumulated in brain, the heavily amyloid-laden anchorless mouse tissue seeded more rapid reactions. Next we compared seeding activities in the brains of mice with similar infectivity titers, but widely divergent PrPRes levels. For this purpose we compared the 263K and 139A scrapie strains in transgenic mice expressing P101L PrPC. Although the brains of 263K-affected mice had no immunoblot-detectable PrPRes, RT-QuIC indicated that seeding activity was comparable to that associated with a high-PrPRes strain, 139A. Thus, in this comparison, RT-QuIC seeding activity correlated more closely with infectivity than with PrPRes levels. We also found that eQuIC, which incorporates a PrPSc immunoprecipitation step, detected seeding activity in plasma from wild-type and anchorless PrP transgenic mice inoculated with 22L, 79A and/or RML scrapie strains. Overall, we conclude that these new mouse-adapted prion seeding assays detect diverse types of PrPSc
Dancing in time: feasibility and acceptability of a contemporary dance programme to modify risk factors for falling in community dwelling older adults
Background: Falls are a common cause of injury in older adults, with the prevention of falls being a priority for public health departments around the world. This study investigated the feasibility, and impact of an 8 week contemporary dance programme on modifiable physical (physical activity status, mobility, sedentary behaviour patterns) and psychosocial (depressive state, fear of falling) risk factors for falls. Methods: An uncontrolled ‘pre-post’ intervention design was used. Three groups of older (60 yrs.+) adults were recruited from local community groups to participate in a 3 separate, 8 week dance programmes. Each programme comprised two, 90 min dance classes per week. Quantitative measures of physical activity, sedentary behaviour, depression, mobility and fear of falling were measured at baseline (T1) and after 8 weeks of dance (T2). Weekly attendance was noted, and post-study qualitative work was conducted with participants in 3 separate focus groups. A combined thematic analysis of these data was conducted. Results: Of the 38 (Mean Age = 77.3 ± 8.4 yrs., 37 females) who attended the dance sessions, 22 (21 females; 1 male; mean age = 74.8, ±8.44) consented to be part of the study. Mean attendance was 14.6 (±2.6) sessions, and mean adherence was 84.3% (±17). Significant increases in moderate and vigorous physical activity were noted, with a significant decrease in sitting time over the weekdays (p < 0.05). Statistically significant decreases in the mean Geriatric Depression Scale (p < 0.05) and fear of falling (p < 0.005) score were noted, and the time taken to complete the TUG test decreased significantly from 10.1 s to 7.7 s over the 8 weeks (p < 0.005). Themes from the focus groups included the dance programme as a means of being active, health Benefits, and dance-related barriers and facilitators. Conclusions: The recruitment of older adults, good adherence and favourability across all three sites indicate that a dance programme is feasible as an intervention, but this may be limited to females only. Contemporary dance has the potential to positively affect the physical activity, sitting behaviour, falls related efficacy, mobility and incidence of depression in older females which could reduce their incidence of falls. An adequately powered study with control groups are required to test this intervention further
Moving in the anthropocene: global reductions in terrestrial mammalian movements
Animal movement is fundamental for ecosystem functioning and species survival, yet the effects of the anthropogenic footprint on animal movements have not been estimated across species. Using a unique GPS-tracking database of 803 individuals across 57 species, we found that movements of mammals in areas with a comparatively high human footprint were on average one-half to one-third the extent of their movements in areas with a low human footprint. We attribute this reduction to behavioral changes of individual animals and to the exclusion of species with long-range movements from areas with higher human impact. Global loss of vagility alters a key ecological trait of animals that affects not only population persistence but also ecosystem processes such as predator-prey interactions, nutrient cycling, and disease transmission
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