614 research outputs found
Space matters: incorporating mechanistically determined spatial patterns into projected impacts of climate change on stream temperature
River temperatures are increasing as a results of climate change, and combined with decreased summertime flows, coldwater species are becoming increasingly stressed. In order to conserve sensitive species, managers need an estimate of how the availability of summertime thermal refuges in rivers will change in the future. Here, we applied the DHSVM-RBM, an existing process-based water temperature model that has been shown to accurately represent temporal variance in water temperature over hours to years. We calibrated this model to empirical data for two case study watersheds (Siletz River, Oregon and Snoqualmie River, Washington) to also ensure representation of observed spatial heterogeneity during summer. We used the model to predict future spatiotemporal patterns in water temperature that may arise as a result of climate change and to assess Pacific salmon vulnerability. We then compared our predictions to those made by statistical models to assess the unique benefits and constraints of a process-based approach. We found that a substantial decrease of snowmelt, and subsequently summer flow, will drive increases in water temperature and spatial variability in future summers. Our vulnerability analysis suggested that for salmon and steelhead exposed to warm August temperatures, conditions are already stressful in lower portions of the case study watersheds, and unlikely to become better in the future. All models predicted generally similar spatial patterns of water temperature in the future; across models, future cool patches will be reduced in number and located farther upstream. However, projected increases in water temperature were strikingly different among models, ranging from about +5 oC in the Snoqualmie River as predicted by DHSVM-RBM, to a negligible change in both watersheds as predicted by statistical methods. This information can be used to identify locations where protection and restoration of coolwater habitats may be most important into the future
The Oral and Skin Microbiomes of Captive Komodo Dragons Are Significantly Shared with Their Habitat.
Examining the way in which animals, including those in captivity, interact with their environment is extremely important for studying ecological processes and developing sophisticated animal husbandry. Here we use the Komodo dragon (Varanus komodoensis) to quantify the degree of sharing of salivary, skin, and fecal microbiota with their environment in captivity. Both species richness and microbial community composition of most surfaces in the Komodo dragon's environment are similar to the Komodo dragon's salivary and skin microbiota but less similar to the stool-associated microbiota. We additionally compared host-environment microbiome sharing between captive Komodo dragons and their enclosures, humans and pets and their homes, and wild amphibians and their environments. We observed similar host-environment microbiome sharing patterns among humans and their pets and Komodo dragons, with high levels of human/pet- and Komodo dragon-associated microbes on home and enclosure surfaces. In contrast, only small amounts of amphibian-associated microbes were detected in the animals' environments. We suggest that the degree of sharing between the Komodo dragon microbiota and its enclosure surfaces has important implications for animal health. These animals evolved in the context of constant exposure to a complex environmental microbiota, which likely shaped their physiological development; in captivity, these animals will not receive significant exposure to microbes not already in their enclosure, with unknown consequences for their health. IMPORTANCE Animals, including humans, have evolved in the context of exposure to a variety of microbial organisms present in the environment. Only recently have humans, and some animals, begun to spend a significant amount of time in enclosed artificial environments, rather than in the more natural spaces in which most of evolution took place. The consequences of this radical change in lifestyle likely extend to the microbes residing in and on our bodies and may have important implications for health and disease. A full characterization of host-microbe sharing in both closed and open environments will provide crucial information that may enable the improvement of health in humans and in captive animals, both of which experience a greater incidence of disease (including chronic illness) than counterparts living under more ecologically natural conditions
An evaluation framework to determine the impact of the Lyme Bay Fisheries and Conservation Reserve and the activities of the Lyme Bay Consultative Committee on ecosystem services and human wellbeing.
This research evaluates the social and economic impact of the management measures that form the Lyme Bay Reserve and the partnership activities of the Lyme Bay Consultative Committee (LBCC) on Lyme Bay resource users. For the purpose of this evaluation it is the combination of the 2008 Statutory Instrument (SI) closure and the more recently designated Site of Community Interest (SCI) that form the boundary of the Lyme Bay Fisheries and Conservation Reserve, termed as the Lyme Bay Reserve. Data is analysed between 2005 and 2015. The results show that the habitats and species of Lyme Bay interact to support the delivery of several ecosystem processes (e.g. primary and secondary production, formation of species habitat) and the realisation of ecosystem services (e.g. fish for food). Overall it is clear that the closure of the area to mobile fishing gear has benefitted static gear fishermen by separating spatial conflict between gear types. The closure has enabled reef habitats to recover which in turn has supported increased catches of some reef associated species e.g. scallops. Further management and support measures agreed through the LBCC have clearly been successful in improving the well-being for those fishermen directly involved in the project. This research represents collaboration between Plymouth University, Exeter University, The Blue Marine Foundation and CEFAS. Input into the evaluation was provided by the Devon and Severn Inshore Fisheries and Conservation Authority (IFCA), the Southern IFCA, local fishermen and fishery representatives
The surveillance for enteric fever in asia project (SEAP), severe typhoid fever surveillance in Africa (SETA), surveillance of enteric fever in India (SEFI), and strategic typhoid alliance across Africa and Asia (STRATAA) population-based enteric fever studies: A Review of methodological similarities and differences
Building on previous multicountry surveillance studies of typhoid and others salmonelloses such as the Diseases of the Most Impoverished program and the Typhoid Surveillance in Africa Project, several ongoing blood culture surveillance studies are generating important data about incidence, severity, transmission, and clinical features of invasive Salmonella infections in sub-Saharan Africa and South Asia. These studies are also characterizing drug resistance patterns in their respective study sites. Each study answers a different set of research questions and employs slightly different methodologies, and the geographies under surveillance differ in size, population density, physician practices, access to healthcare facilities, and access to microbiologically safe water and improved sanitation. These differences in part reflect the heterogeneity of the epidemiology of invasive salmonellosis globally, and thus enable generation of data that are useful to policymakers in decision-making for the introduction of typhoid conjugate vaccines (TCVs). Moreover, each study is evaluating the large-scale deployment of TCVs, and may ultimately be used to assess post-introduction vaccine impact. The data generated by these studies will also be used to refine global disease burden estimates. It is important to ensure that lessons learned from these studies not only inform vaccination policy, but also are incorporated into sustainable, low-cost, integrated vaccine-preventable disease surveillance systems
An evaluation of the social and economic impact of a Marine Protected Area on commercial fisheries
A marine natural capital asset and risk register—Towards securing the benefits from marine systems and linked ecosystem services
Captive reptile mortality rates in the home and implications for the wildlife trade
The trade in wildlife and keeping of exotic pets is subject to varying levels of national and international regulation and is a topic often attracting controversy. Reptiles are popular exotic pets and comprise a substantial component of the live animal trade. High mortality of traded animals raises welfare concerns, and also has implications for conservation if collection from the wild is required to meet demand. Mortality of reptiles can occur at any stage of the trade chain from collector to consumer. However, there is limited information on mortality rates of reptiles across trade chains, particularly amongst final consumers in the home. We investigated mortality rates of reptiles amongst consumers using a specialised technique for asking sensitive questions, additive Randomised Response Technique (aRRT), as well as direct questioning (DQ). Overall, 3.6% of snakes, chelonians and lizards died within one year of acquisition. Boas and pythons had the lowest reported mortality rates of 1.9% and chameleons had the highest at 28.2%. More than 97% of snakes, 87% of lizards and 69% of chelonians acquired by respondents over five years were reported to be captive bred and results suggest that mortality rates may be lowest for captive bred individuals. Estimates of mortality from aRRT and DQ did not differ significantly which is in line with our findings that respondents did not find questions about reptile mortality to be sensitive. This research suggests that captive reptile mortality in the home is rather low, and identifies those taxa where further effort could be made to reduce mortality rate
Little Things
We present LITTLE THINGS (Local Irregulars That Trace Luminosity Extremes,
The HI Nearby Galaxy Survey) that is aimed at determining what drives star
formation in dwarf galaxies. This is a multi-wavelength survey of 37 Dwarf
Irregular and 4 Blue Compact Dwarf galaxies that is centered around HI-line
data obtained with the National Radio Astronomy Observatory (NRAO) Very Large
Array (VLA). The HI-line data are characterized by high sensitivity (less than
1.1 mJy/beam per channel), high spectral resolution (less than or equal to 2.6
km/s), and high angular resolution (~6 arcseconds. The LITTLE THINGS sample
contains dwarf galaxies that are relatively nearby (less than or equal to 10.3
Mpc; 6 arcseconds is less than or equal to 300 pc), that were known to contain
atomic hydrogen, the fuel for star formation, and that cover a large range in
dwarf galactic properties. We describe our VLA data acquisition, calibration,
and mapping procedures, as well as HI map characteristics, and show channel
maps, moment maps, velocity-flux profiles, and surface gas density profiles. In
addition to the HI data we have GALEX UV and ground-based UBV and Halpha images
for most of the galaxies, and JHK images for some. Spitzer mid-IR images are
available for many of the galaxies as well. These data sets are available
on-line.Comment: In press in A
A Blood-Based Screening Tool for Alzheimer's Disease That Spans Serum and Plasma: Findings from TARC and ADNI
There is no rapid and cost effective tool that can be implemented as a front-line screening tool for Alzheimer's disease (AD) at the population level.To generate and cross-validate a blood-based screener for AD that yields acceptable accuracy across both serum and plasma. status) data.Alzheimer's disease.11 proteins met our criteria and were utilized for the biomarker risk score. The random forest (RF) biomarker risk score from the TARC serum samples (training set) yielded adequate accuracy in the ADNI plasma sample (training set) (AUC = 0.70, sensitivity (SN) = 0.54 and specificity (SP) = 0.78), which was below that obtained from ADNI cerebral spinal fluid (CSF) analyses (t-tau/Aβ ratio AUC = 0.92). However, the full algorithm yielded excellent accuracy (AUC = 0.88, SN = 0.75, and SP = 0.91). The likelihood ratio of having AD based on a positive test finding (LR+) = 7.03 (SE = 1.17; 95% CI = 4.49–14.47), the likelihood ratio of not having AD based on the algorithm (LR−) = 3.55 (SE = 1.15; 2.22–5.71), and the odds ratio of AD were calculated in the ADNI cohort (OR) = 28.70 (1.55; 95% CI = 11.86–69.47).It is possible to create a blood-based screening algorithm that works across both serum and plasma that provides a comparable screening accuracy to that obtained from CSF analyses
High-resolution mass models of dwarf galaxies from LITTLE THINGS
We present high-resolution rotation curves and mass models of 26 dwarf galaxies from LITTLE THINGS. LITTLE THINGS is a high-resolution Very Large Array HI survey for nearby dwarf galaxies in the local volume within 11 Mpc. The rotation curves of the sample galaxies derived in a homogeneous and consistent manner are combined with Spitzer archival 3.6 micron and ancillary optical U, B, and V images to construct mass models of the galaxies. We decompose the rotation curves in terms of the dynamical contributions by baryons and dark matter halos, and compare the latter with those of dwarf galaxies from THINGS as well as Lambda CDM SPH simulations in which the effect of baryonic feedback processes is included. Being generally consistent with THINGS and simulated dwarf galaxies, most of the LITTLE THINGS sample galaxies show a linear increase of the rotation curve in their inner regions, which gives shallower logarithmic inner slopes alpha of their dark matter density profiles. The mean value of the slopes of the 26 LITTLE THINGS dwarf galaxies is alpha =-0.32 +/- 0.24 which is in accordance with the previous results found for low surface brightness galaxies (alpha = -0.2 +/- 0.2) as well as the seven THINGS dwarf galaxies (alpha =-0.29 +/- 0.07). However, this significantly deviates from the cusp-like dark matter distribution predicted by dark-matter-only Lambda CDM simulations. Instead our results are more in line with the shallower slopes found in the Lambda CDM SPH simulations of dwarf galaxies in which the effect of baryonic feedback processes is included. In addition, we discuss the central dark matter distribution of DDO 210 whose stellar mass is relatively low in our sample to examine the scenario of inefficient supernova feedback in low mass dwarf galaxies predicted from recent Lambda SPH simulations of dwarf galaxies where central cusps still remain.Peer reviewe
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