43 research outputs found
Red-throated diver breeding ecology and nest survival on Shetland
The aim of this thesis is to identify and measure biological, environmental and behavioural factors relevant to red-throated diver breeding ecology and then to distinguish their relative importance in determining breeding success and nest survival. Migratory birds that breed at high latitudes are at particular risk from human mediated climate change because the time window available for breeding in these areas is short, and if peak abundance of key prey items alters in response to climatic cues (Shultz et al. 2009), it may not be possible for birds to adjust their breeding strategies to compensate. Moreover, large scale environmental cues that migratory birds use to time their migration and breeding may become less reliable (Both & Visser 2001; Frederiksen et al. 2007). For such species it is particularly important to understand and monitor breeding biology, particularly the factors that determine breeding performance and nest survival, as these are likely to respond to large scale ecosystem changes before population changes are detected, and additionally provide valuable information that can be used to establish conservation priorities for the species. Red- throated divers are migratory fish-eating seabirds with a predominantly arctic breeding distribution that have apparently declined in large areas of their breeding range in the recent past (Groves et al. 1996; Hagemeijer & Blair 1997). In addition to the demonstrated effects of food availability (Eriksson & Sundberg 1991; Ball 1994), disturbance (Pakarinen & Järvinen 1984) and vulnerability to pollutants (Eriksson & Lindberg 2005) on breeding performance, direct and indirect effects of climate change are predicted, in particular a contracting of the European breeding range (Huntley et al. 2006) and vulnerability to both onshore and offshore renewable energy developments (Garthe & Huppop 2004; Halley & Hopshaug 2007).This research tests the importance of proximate factors influencing red-throated diver breeding performance using modern nest survival analysis with the intention that the findings will provide clues about the larger mechanisms driving population processes. First I developed a number of linear regression models using nest temperature signatures and photographic measures of chick size that; allowed timing of breeding to be estimated from a single field visit; were of comparable accuracy to established methods such as egg flotation (Westerkov 1950); and extended the period during the breeding cycle when timing of breeding estimates could be made, to include the later stages of incubation and chick rearing. I used these techniques to obtain timing of breeding estimates for the study sample. This allowed me to use an information-theoretic modelling approach (Burnham & Anderson 2002) to determine the daily nest survival rate and evaluate the importance of a set of biological and environmental effects on red-throated diver nest survival patterns. I found support for models that suggested that nest survival increased with nest age and individual quality and decreased with laying date. I explored the effects of habitat characteristics at different spatial scales and found support for models that suggested that both environmental conditions and predator avoidance were important determinants of nest survival rate. Finally I examined nest attendance behaviour and variation in nest temperature during incubation and found patterns in attendance in relation to nest age and through the day but no strong evidence of trends in survival in relation to attendance patterns
Plasma endocannabinoids in cocaine dependence and their interaction with cocaine craving and metabotropic glutamate receptor 5 density in the human brain
Animal models indicate that the endocannabinoid system (ECS) plays a modulatory role in stress and reward processing, both crucially impaired in addictive disorders. Preclinical findings showed endocannabinoid-modulated synaptic plasticity in reward brain networks linked to the metabotropic-glutamate-5 receptor (mGluR5), contributing to drug-reinforcing effects and drug-seeking behavior. Although animal models postulate a link between ECS and cocaine addiction, human translational studies are lacking. Here, we tested previous preclinical findings by investigating plasma endocannabinoids (eCBs) anandamide (AEA), 2-arachidonoylglycerol (2-AG), and the related N-acylethanolamines (NAEs) palmitoylethanolamide (PEA) and oleoylethanolamide (OEA), including their interaction with cerebral mGluR5, in chronic cocaine users (CU). We compared basal plasma concentrations between chronic CU (N=103; 69 recreational CU and 34 dependent CU) and stimulant-naïve healthy controls (N=92). Follow-up basal eCB/NAE plasma levels after 12 months were used for reliability and stability check (CU: N=33; controls: N=43). In an additional analysis usingC-ABP688 positron emission tomography (PET) in a male subsample (CU: N=18; controls: N=16), we investigated the relationships between eCBs/NAEs and mGluR5 density in the brain. We found higher 2-AG plasma levels in dependent CU compared to controls and recreational CU. 2-AG levels were stable over time across all groups. In the PET-subsample, a positive association between 2-AG and mGluR5 brain density only in CU was found. Our results corroborate animal findings suggesting an alteration of the ECS in cocaine dependence and an association between peripheral 2-AG levels and cerebral mGluR5 in humans. Therefore, the ECS might be a promising pharmaco-therapeutic target for novel treatments of cocaine dependence
Plasma endocannabinoids in cocaine dependence and their relation to cerebral metabotropic glutamate receptor 5 density
Animal models indicate that the endocannabinoid system (ECS) plays a modulatory role in stress and reward processing, both crucially impaired in addictive disorders. Preclinical findings showed endocannabinoid-modulated synaptic plasticity in reward brain networks linked to the metabotropic-glutamate-5 receptor (mGluR5), contributing to drug-reinforcing effects and drug-seeking behavior. Although animal models postulate a link between ECS and cocaine addiction, human translational studies are lacking. Here, we tested previous preclinical findings by investigating plasma endocannabinoids (eCBs) anandamide (AEA), 2-arachidonoylglycerol (2-AG), and the related N-acylethanolamines (NAEs) palmitoylethanolamide (PEA) and oleoylethanolamide (OEA), including their interaction with cerebral mGluR5, in chronic cocaine users (CU). We compared basal plasma concentrations between chronic CU (N = 103; 69 recreational CU and 34 dependent CU) and stimulant-naïve healthy controls (N = 92). Follow-up basal eCB/NAE plasma levels after 12 months were used for reliability and stability check (CU: N = 33; controls: N = 43). In an additional analysis using C-ABP688 positron emission tomography (PET) in a male subsample (CU: N = 18; controls: N = 16), we investigated the relationships between eCBs/NAEs and mGluR5 density in the brain. We found higher 2-AG plasma levels in dependent CU compared to controls and recreational CU. 2-AG levels were stable over time across all groups. In the PET-subsample, a positive association between 2-AG and mGluR5 brain density only in CU was found. Our results corroborate animal findings suggesting an alteration of the ECS in cocaine dependence and an association between peripheral 2-AG levels and cerebral mGluR5 in humans. Therefore, the ECS might be a promising pharmaco-therapeutic target for novel treatments of cocaine dependence
Association of Long-Term Nicotine Abstinence With Normal Metabotropic Glutamate Receptor-5 Binding
A review of raptor carcass persistence trials and the practical implications for fatality estimation at wind farms
Bird and bat turbine collision fatalities are a principal biodiversity impact at wind energy facilities. Raptors are a group at particular risk and often the focus of post-construction fatality monitoring programs. To estimate fatalities from detected carcasses requires correction for biases, including for carcasses that are removed or decompose before the following search. This is addressed through persistence trials, where carcasses are monitored until no longer detectable or the trial ends. Sourcing sufficient raptor carcasses for trials is challenging and surrogates that are typically used often have shorter persistence times than raptors. We collated information from raptor carcass persistence trials to evaluate consistencies between trials and assess the implications of using persistence values from other studies in wind facility fatality estimates. We compiled individual raptor carcass persistence times from published sources along with information on methods and location, estimated carcass persistence using GenEst and ran full fatality estimates using the carcass persistence estimates and mock datasets for other information. We compiled results from 22 trials from 17 sites across four terrestrial biomes, with trials lasting between 7 and 365 days and involving between 11 and 115 carcasses. Median carcass persistence was estimated at 420 days (90% confidence interval (CI) of 290 to 607 days) for the full dataset. Persistence time varied significantly between trials (trial-specific persistence estimates of 14 (5–42) days to 1,586 (816–3,084) days) but not between terrestrial biomes. We also found no significant relationship between either the number of carcasses in the trial or trial duration and estimated carcass persistence. Using a mock dataset with 12 observed fatalities, we estimated annual fatalities of 25 (16–33) or 26 (17–36) individuals using a 14- or 28-day search interval respectively using global dataset. When using trial-specific carcass persistence estimates and the same mock dataset, estimated annual fatalities ranged from 22 (14–30) to 37 (21–63) individuals for a 14-day search interval, and from 22 (15–31) to 47 (26–84) individuals for a 28-day search interval. The different raptor carcass persistence rates between trials translated to small effects on fatality estimates when using recommended search frequencies, since persistence rates were generally much longer than the search interval. When threatened raptor species, or raptors of particular concern to stakeholders are present, and no site-specific carcass persistence estimates are available, projects should use the lowest median carcass persistence estimate from this study to provide precautionary estimates of fatalities. At sites without threatened species, or where the risk of collision to raptors is low, the global median carcass persistence estimate from this review could be used to provide a plausible estimate for annual raptor fatalities
How ready is general practice to improve quality in chronic kidney disease? A diagnostic analysis
Chronic kidney disease (CKD) is associated with increased cardiovascular mortality and morbidity as well as progression to established renal failure. Interventions in primary care, particularly the lowering of blood pressure in individuals with CKD and proteinuria and diabetes, can slow disease progression. This evidence base is codified in national guidance and in a simplified form in pay-for-performance targets. Prior to conducting the QICKD study - a cluster of quality-improvement interventions with reduction of blood pressure as its primary outcome measure - a diagnostic analysis was conducted to assess the relevance of the intended interventions
Disability measurement in the anxiety disorders: Comparison of three brief measures
General measures of disablement are powerful tools in clinical settings as they provide a link between clinic and community populations and allow cross-disorder comparisons. Because of their generic nature, they allow the transmittal of comprehensible health planning information to decision makers. We located no studies of such general disability measures in the anxiety disorders and decided to examine the properties of three brief generic measures in an anxiety disorders clinic. Consecutive attenders (N=168) were administered the Medical Outcomes Study Short Form-12 item (SF-12), the Brief Disability Questionnaire (BDQ), and a measure of the number of disability days due to health over the past 4 weeks. These measures were compared on their ability to discriminate within the clinic and in comparison to a representative community group. The mental health scale of the SF-12 was the most sensitive of the generic measures to differences in functioning, and is recommended as a measure of such for people with anxiety disorders. Attenders at this anxiety clinic reported high levels of disablement, and normative data on the general measures are provided
The Intensive Care Unit Perspective of Becoming a Level I Trauma Center: Challenges of Strategy, Leadership, and Operations Management
Plasma endocannabinoids in cocaine dependence and their relation to cerebral metabotropic glutamate receptor 5 density
Animal models indicate that the endocannabinoid system (ECS) plays a modulatory role in stress and reward processing, both crucially impaired in addictive disorders. Preclinical findings showed endocannabinoid-modulated synaptic plasticity in reward brain networks linked to the metabotropic-glutamate-5 receptor (mGluR5), contributing to drug-reinforcing effects and drug-seeking behavior. Although animal models postulate a link between ECS and cocaine addiction, human translational studies are lacking. Here, we tested previous preclinical findings by investigating plasma endocannabinoids (eCBs) anandamide (AEA), 2-arachidonoylglycerol (2-AG), and the related N-acylethanolamines (NAEs) palmitoylethanolamide (PEA) and oleoylethanolamide (OEA), including their interaction with cerebral mGluR5, in chronic cocaine users (CU). We compared basal plasma concentrations between chronic CU (N = 103; 69 recreational CU and 34 dependent CU) and stimulant-naïve healthy controls (N = 92). Follow-up basal eCB/NAE plasma levels after 12 months were used for reliability and stability check (CU: N = 33; controls: N = 43). In an additional analysis using ¹¹C-ABP688 positron emission tomography (PET) in a male subsample (CU: N = 18; controls: N = 16), we investigated the relationships between eCBs/NAEs and mGluR5 density in the brain. We found higher 2-AG plasma levels in dependent CU compared to controls and recreational CU. 2-AG levels were stable over time across all groups. In the PET-subsample, a positive association between 2-AG and mGluR5 brain density only in CU was found. Our results corroborate animal findings suggesting an alteration of the ECS in cocaine dependence and an association between peripheral 2-AG levels and cerebral mGluR5 in humans. Therefore, the ECS might be a promising pharmaco-therapeutic target for novel treatments of cocaine dependence.ISSN:2158-318