649 research outputs found
Protectors of Wellbeing During the COVID-19 Pandemic: Key Roles for Gratitude and Tragic Optimism in a UK-Based Cohort
The COVID-19 pandemic has presented a global threat to physical and mental health worldwide. Research has highlighted adverse impacts of COVID-19 on wellbeing but has yet to offer insights as to how wellbeing may be protected. Inspired by developments in wellbeing science and guided by our own theoretical framework (the GENIAL model), we examined the role of various potentially protective factors in a sample of 138 participants from the United Kingdom. Protective factors included physical activity (i.e., a health behaviour that helps to build psychological wellbeing), tragic optimism (optimism in the face of tragedy), gratitude (a prosocial emotion), social support (the perception or experience of being loved, cared for, and valued by others), and nature connectedness (physical and psychological connection to nature). Initial analysis involved the application of one-sample t-tests, which confirmed that wellbeing (measured by the Warwick-Edinburgh Mental Well-being scale) in the current sample (N = 138; M = 46.08, SD = 9.22) was significantly lower compared to previous samples (d = −0.36 and d = −0.41). Protective factors were observed to account for up to 50% of variance in wellbeing in a hierarchical linear regression that controlled for a range of sociostructural factors including age, gender, and subjective social status, which impact on wellbeing but lie beyond individual control. Gratitude and tragic optimism emerged as significant contributors to the model. Our results identify key psychological attributes that may be harnessed through various positive psychology strategies to mitigate the adverse impacts of hardship and suffering, consistent with an existential positive psychology of suffering
Surveying Position Based Routing Protocols for Wireless Sensor and Ad-hoc Networks
A focus of the scientific community is to design network oriented position-based routing protocols and this has resulted in a very high number of algorithms, different in approach and performance and each suited only to particular applications. However, though numerous, very few position-based algorithms have actually been adopted for commercial purposes. This article is a survey of almost 50 position-based routing protocols and it comes as an aid in the implementation of this type of routing in various applications which may need to consider the advantages and pitfalls of position-based routing. An emphasis is made on geographic routing, whose notion is clarified as a more restrictive and more efficient type of position-based routing. The protocols are therefore divided into geographic and non-geographic routing protocols and each is characterized according to a number of network design issues and presented in a comparative manner from multiple points of view. The main requirements of current general applications are also studied and, depending on these, the survey proposes a number of protocols for use in particular application areas. This aims to help both researchers and potential users assess and choose the protocol best suited to their interest
Childhood- versus Adolescent-Onset Antisocial Youth with Conduct Disorder: Psychiatric Illness, Neuropsychological and Psychosocial Function
The present study investigates whether youths with childhood-onset antisocial behavior have higher rates of psychiatric illness, neuropsychological and psychosocial dysfunction than youths who engage in antisocial behavior for the first time in adolescence. Prior studies have generally focused on single domains of function in heterogeneous samples. The present study also examined the extent to which adolescent-onset antisocial behavior can be considered normative, an assumption of Moffitt's dual taxonomy model.Forty-three subjects (34 males, 9 females, mean age = 15.31, age range 12-21) with a diagnosis of conduct disorder (CD) were recruited through Headspace Services and the Juvenile Justice Community Centre. We compared childhood-onset antisocial youths (n = 23) with adolescent-onset antisocial youths (n = 20) with a conduct disorder, across a battery of psychiatric, neuropsychological and psychosocial measures. Neuropsychological function of both groups was also compared with normative scores from control samples.The childhood-onset group displayed deficits in verbal learning and memory, higher rates of psychosis, childhood maltreatment and more serious violent behavior, all effects associated with a large effect size. Both groups had impaired executive function, falling within the extremely low range (severely impaired).Childhood-onset CD displayed greater cognitive impairment, more psychiatric symptoms and committed more serious violent offences. The finding of severe executive impairment in both childhood- and adolescent-onset groupings challenges the assumption that adolescent-onset antisocial behavior is a normative process
Editorial: Improving wellbeing in patients with chronic conditions: Theory, evidence, and opportunities
Cerebral blood flow links insulin resistance and baroreflex sensitivity
Insulin resistance confers risk for diabetes mellitus and associates with a reduced capacity of the arterial baroreflex to regulate blood pressure. Importantly, several brain regions that comprise the central autonomic network, which controls the baroreflex, are also sensitive to the neuromodulatory effects of insulin. However, it is unknown whether peripheral insulin resistance relates to activity within central autonomic network regions, which may in turn relate to reduced baroreflex regulation. Accordingly, we tested whether resting cerebral blood flow within central autonomic regions statistically mediated the relationship between insulin resistance and an indirect indicator of baroreflex regulation; namely, baroreflex sensitivity. Subjects were 92 community-dwelling adults free of confounding medical illnesses (48 men, 30-50 years old) who completed protocols to assess fasting insulin and glucose levels, resting baroreflex sensitivity, and resting cerebral blood flow. Baroreflex sensitivity was quantified by measuring the magnitude of spontaneous and sequential associations between beat-by-beat systolic blood pressure and heart rate changes. Individuals with greater insulin resistance, as measured by the homeostatic model assessment, exhibited reduced baroreflex sensitivity (b = -0.16, p < .05). Moreover, the relationship between insulin resistance and baroreflex sensitivity was statistically mediated by cerebral blood flow in central autonomic regions, including the insula and cingulate cortex (mediation coefficients < -0.06, p-values < .01). Activity within the central autonomic network may link insulin resistance to reduced baroreflex sensitivity. Our observations may help to characterize the neural pathways by which insulin resistance, and possibly diabetes mellitus, relates to adverse cardiovascular outcomes. © 2013 Ryan et al
Seamount influences on mid-water shrimps (Decapoda) and Gnathophausiids (Lophogastridea) of the South-West Indian ridge
This study was conducted under the UNDP/IUCN project, funded by the Global Environment Facility (GEF). The authors thank the School of Biology at the University of St Andrews and the National Environmental Research Council (NERC) for funding toward Tom B Letessier's PhD.Maintenance of often-observed elevated levels of pelagic diversity and biomass on seamounts, that are of relevance to conservation and fishery management, involves complex interactions between physical and biological variables that remain poorly understood. To untangle these biophysical processes we explore factors influencing the distribution of epi- and meso-pelagic (0–1000 m) micronektonic crustaceans (>15 mm; order Lophogastridea, family Gnathophausiidea; and order Decapoda) on and off seamounts along the South West Indian Ridge (SWIR, 27° to 42°S) and on a seamount off the Madagascar Ridge (31.6°S, 42.8°E). Thirty-one species of micronektic crustaceans were caught using mid-water trawls within the study are but there was no apparent latitude-related patterns in species richness or abundance. Species richness predicted by rarefraction curves and numerical abundance was highest in the vicinity (800 m). The dominant species assemblage comprised the shrimps Systellaspis debilis (37%) and Sergia prehensilis (34%), and was restricted to seamounts on the subtropical SWIR. Our observations suggest that the ‘oasis effect’ of seamounts conventionally associated with higher trophic levels is also applicable to pelagic micronektic crustaceans at lower trophic levels. We suggest that the enhanced biomass and species richness attributed is due to ‘habitat enrichment’, whereby seamounts provide favourable habitats for both pelagic and bentho-pelagic mid-water crustaceans.PostprintPeer reviewe
Relative sea-level change in Connecticut (USA) during the last 2200 yrs
We produced a relative sea-level (RSL) reconstruction from Connecticut (USA) spanning the last ∼2200 yrs that is free from the influence of sediment compaction. The reconstruction used a suite of vertically- and laterally-ordered sediment samples ≤2 cm above bedrock that were collected by excavating a trench along an evenly-sloped bedrock surface. Paleomarsh elevation was reconstructed using a regional-scale transfer function trained on the modern distribution of foraminifera on Long Island Sound salt marshes and supported by bulk-sediment δ13C measurements. The history of sediment accumulation was estimated using an age-elevation model constrained by radiocarbon dates and recognition of pollution horizons of known age. The RSL reconstruction was combined with regional tide-gauge measurements spanning the last ∼150 yrs before being quantitatively analyzed using an error-in-variables integrated Gaussian process model to identify sea-level trends with formal and appropriate treatment of uncertainty and the temporal distribution of data. RSL rise was stable (∼1 mm/yr) from ∼200 BCE to ∼1000 CE, slowed to a minimum rate of rise (0.41 mm/yr) at ∼1400 CE, and then accelerated continuously to reach a current rate of 3.2 mm/yr, which is the fastest, century-scale rate of the last 2200 yrs. Change point analysis identified that modern rates of rise in Connecticut began at 1850–1886 CE. This timing is synchronous with changes recorded at other sites on the U.S. Atlantic coast and is likely the local expression of a global sea-level change. Earlier sea-level trends show coherence north of Cape Hatteras that are contrasted with southern sites. This pattern may represent centennial-scale variability in the position and/or strength of the Gulf Stream. Comparison of the new record to three existing and reanalyzed RSL reconstructions from the same site developed using sediment cores indicates that compaction is unlikely to significantly distort RSL reconstructions produced from shallow (∼2–3 m thick) sequences of salt-marsh peat
Fecal steroids as a potential tool for conservation paleobiology in East Africa
Conservation paleobiology seeks to leverage proxy reconstructions of ecological communities and environmental conditions to predict future changes and inform management decisions. Populations of East African megafauna likely changed during the Holocene in response to trends and events in the regional hydroclimate, but reconstructing these populations requires development of new proxies. We examine if fecal steroids are a viable proxy for megafauna populations since they are well preserved in sedimentary archives. We measured eleven fecal steroids in 87 fresh dung samples representing 22 species of megafauna in the Maasai Mara National Reserve (Kenya) and a further seven samples from captive animals. Using this reference library, four distinctive groups are identified, which reflect diet and biochemical modification of these inputs during digestion by the gut microbiome. Carnivore dung is characterized by more than ~ 75% cholesterol and primate dung includes uniquely high proportions of coprostanol. Two groups of herbivore are distinguished by their differing proportions of phytosterols that are consumed by eating plants and 5β-stanols produced during digestion. Under cross validation a random forests statistical model accurately classified 72% of dung samples to the species level using fecal steroids. Variability among individuals and between wild and captive animals suggests that fecal steroids in herbivore dung may reflect diversity and variability in diet, while a lack of variability in carnivore dung indicates that they cannot be identified to the species level in most instances. Our results suggest that fecal steroids may have utility in reconstructing the time-evolving composition megafauna populations in East Africa
Relative Sea-Level Trends in New York City During the Past 1500 Years
New York City (NYC) is threatened by 21st-century relative sea-level (RSL) rise because it will experience a trend that exceeds the global mean and has high concentrations of low-lying infrastructure and socioeconomic activity. To provide a long-term context for anticipated trends, we reconstructed RSL change during the past ~1500 years using a core of salt-marsh sediment from Pelham Bay in The Bronx. Foraminifera and bulk-sediment δ13C values were used as sea-level indicators. The history of sediment accumulation was established by radiocarbon dating and recognition of pollution and land-use trends of known age in down-core elemental, isotopic, and pollen profiles. The reconstruction was generated within a Bayesian hierarchical model to accommodate multiple proxies and to provide a unified statistical framework for quantifying uncertainty. We show that RSL in NYC rose by ~1.70 m since ~575 CE (including ~0.38 m since 1850 CE). The rate of RSL rise increased markedly at 1812–1913 CE from ~1.0 to ~2.5 mm/yr, which coincides with other reconstructions along the US Atlantic coast. We investigated the possible influence of tidal-range change in Long Island Sound on our reconstruction using a regional tidal model, and we demonstrate that this effect was likely small. However, future tidal-range change could exacerbate the impacts of RSL rise in communities bordering Long Island Sound. The current rate of RSL rise is the fastest that NYC has experienced for \u3e1500 years, and its ongoing acceleration suggests that projections of 21st-century local RSL rise will be realized
Taraxerol abundance as a proxy for in situ Mangrove sediment
Mangrove sediments are valuable archives of relative sea-level change if they can be distinguished in the stratigraphic record from other organic-rich depositional environments (e.g., freshwater swamps). Proxies for establishing environment of deposition can be poorly preserved (e.g., foraminifera) in mangrove sediment. Consequently, differentiating mangrove and freshwater sediment in the stratigraphic record is often subjective. We explore if biomarkers can objectively identify mangrove sediment with emphasis on their utility for reconstructing relative sea level. Our approach is specific to identifying in situ sediment, which has received less attention than identifying allochthonous mangrove organic matter. To characterize mangrove and non-mangrove (freshwater) environments, we measured n-alkane, sterol, and triterpenoid abundances in surface sediments at three sites in the Federated States of Micronesia. Elevated taraxerol abundance is diagnostic of sediment accumulating in mangroves and taraxerol is particularly abundant beneath monospecific stands of Rhizophora spp. Taraxerol was undetectable in freshwater sediment. Other triterpenoids are more abundant in mangrove sediment than in freshwater sediment. Using cores from Micronesian mangroves, we examine if biomarkers in sediments are indicative of in situ deposition in a mangrove, and have utility as a relative sea-level proxy. Taraxerol concentrations in cores are comparable to surface mangrove sediments, which indicates deposition in a mangrove. This interpretation is supported by pollen assemblages. Downcore taraxerol variability may reflect changing inputs from Rhizophora spp. rather than diagenesis. We propose that taraxerol is a proxy that differentiates between organic sediment that accumulated in mangrove vs. freshwater environments, lending it utility for reconstructing relative sea level
- …