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1.
Ecology ; 104(11): e4158, 2023 11.
Article in English | MEDLINE | ID: mdl-37632351

ABSTRACT

Spatially synchronized population dynamics are common in nature, and understanding their causes is key for predicting species persistence. A main driver of synchrony between populations of the same species is shared environmental conditions, which cause populations closer together in space to be more synchronized than populations further from one another. Most theoretical and empirical understanding of this driver considers resident species. For migratory species, however, the degree of spatial autocorrelation in the environment may change across seasons and vary by their geographic location along the migratory route or on a nonbreeding ground, complicating the synchronizing effect of the environment. Migratory species show a variety of different strategies in how they disperse to and aggregate on nonbreeding grounds, ranging from completely shared nonbreeding grounds to multiple different ones. Depending on the sensitivity to environmental conditions off the breeding grounds, we can expect that migration and overwintering strategies will impact the extent and spatial pattern of population synchrony on the breeding grounds. Here, we use spatial population-dynamic modeling and simulations to investigate the relationship between seasonal environmental autocorrelation and migration characteristics. Our model shows that the effects of environmental autocorrelation experienced off the breeding ground on population synchrony depend on the number and size of nonbreeding grounds, and how populations migrate in relation to neighboring populations. When populations migrated to multiple nonbreeding grounds, spatial population synchrony increased with increasing environmental autocorrelation between nonbreeding grounds. Populations that migrated to the same place as near neighbors had higher synchrony at short distances than populations that migrated randomly. However, synchrony declined less across increasing distances for the random migration strategy. The differences in synchrony between migration strategies were most pronounced when the environmental autocorrelation between nonbreeding grounds was low. These results show the importance of considering migration when studying spatial population synchrony and predicting patterns of synchrony and population viability under global environmental change. Climate change and habitat loss and fragmentation may cause range shifts and changes in migratory strategies, as well as changes in the mean and spatial autocorrelation of the environment, which can alter the scale and patterns observed in spatial population synchrony.


Subject(s)
Climate Change , Ecosystem , Seasons , Population Dynamics , Animal Migration
2.
J Anim Ecol ; 92(9): 1904-1918, 2023 09.
Article in English | MEDLINE | ID: mdl-37448134

ABSTRACT

Spatial population synchrony is common among populations of the same species and is an important predictor of extinction risk. Despite the potential consequences for metapopulation persistence, we still largely lack understanding of what makes one species more likely to be synchronized than another given the same environmental conditions. Generally, environmental conditions in a shared environment or a species' sensitivity to the environment can explain the extent of synchrony. Populations that are closer together experience more similar fluctuations in their environments than those populations that are further apart and are therefore more synchronized. The relative importance of environmental and demographic stochasticity for population dynamics is strongly linked to species' life-history traits, such as pace of life, which may impact population synchrony. For populations that migrate, there may be multiple environmental conditions at different locations driving synchrony. However, the importance of life history and migration tactics in determining patterns of spatial population synchrony have rarely been explored empirically. We therefore hypothesize that increasing generation time, a proxy for pace of life, would decrease spatial population synchrony and that migrants would be less synchronized than resident species. We used population abundance data on breeding birds from four countries to investigate patterns of spatial population synchrony in growth rate and abundance. We calculated the mean spatial population synchrony between log-transformed population growth rates or log-transformed abundances for each species and country separately. We investigated differences in synchrony across generation times in resident (n = 67), short-distance migrant (n = 86) and long-distance migrant (n = 39) bird species. Species with shorter generation times were more synchronized than species with longer generation times. Short-distance migrants were more synchronized than long-distance migrants and resident birds. Our results provide novel empirical links between spatial population synchrony and species traits known to be of key importance for population dynamics, generation time and migration tactics. We show how these different mechanisms can be combined to understand species-specific causes of spatial population synchrony. Understanding these specific drivers of spatial population synchrony is important in the face of increasingly severe threats to biodiversity and could be key for successful future conservation outcomes.


Subject(s)
Ecosystem , Population Growth , Animals , Seasons , Population Dynamics , Birds
3.
Injury ; 54(8): 110918, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37421836

ABSTRACT

INTRODUCTION: The management of paediatric femoral shaft fractures is expensive and is guided by age and fracture characteristics. The primary aim of this study was to perform a cost evaluation for managing paediatric femoral shaft fractures. The secondary aim of this study was to perform and compare costs of the different techniques of managing paediatric femoral shaft fractures. METHODS: Ninety-eight femoral shaft fractures in children aged ≤16 were identified between 01/06/2014-30/06/2019. Retrospective data of clinical complications were obtained on infection, malunion and non-union. Data on additional intervention, reoperations for complications and routine removal of metal work were obtained. Costing analysis was performed by a bottom-up calculation, and gathering Patient Level Information and Costing System (PLICS) data. RESULTS: There were 41 hip spica casting (HSC), 21 flexible intramedullary nailing (FIN), 14 submuscular plating (SMP), 19 rigid intramedullary nailing (RIN) and 3 external fixation (EF). Complications observed were HSC 3(7%); FIN 8(38%); SMP 2(14%); RIN 1(5%); EF 2(67%). The total costs for managing femoral shaft fractures were £8,955pp the costs for the different managements were; HSC £3,442pp; FIN £7,739pp; SMP £6,953pp; RIN £8,925pp; EF £19,116pp. The additional costs incurred for managing complications and routine removal of metal work for the internal fixation methods were: HSC 0.7%, FIN 23.7%, SMP 16.3%, RIN 10.9%, EF 28.1%. CONCLUSION: The operative management of paediatric femoral shaft fractures is associated with a high cost burden and this study demonstrates how financial data can be used to influence clinical management strategy. RIN carry a high initial implant cost however when considering the additional costs, such as treating complications it remains comparable to other modes of fixation. Our cost analysis did not demonstrate a significant difference between FIN, SMP and RIN. Due to the clinical complications observed and associated additional costs, we have discontinued the routine use of FIN for femoral shaft fractures at our centre. We recognise other centres may have a different complication and cost profile for each technique, but recommend they evaluate their practice given the potential economic benefit it has on the service provider.


Subject(s)
Femoral Fractures , Fracture Fixation, Intramedullary , Humans , Child , Retrospective Studies , Trauma Centers , Fracture Fixation, Intramedullary/methods , Femoral Fractures/surgery , Bone Nails , Treatment Outcome
4.
Psychiatry Res ; 325: 115218, 2023 07.
Article in English | MEDLINE | ID: mdl-37146462

ABSTRACT

Loneliness is a common, yet distressing experience associated with adverse outcomes including substance use problems and psychiatric disorders. To what extent these associations reflect genetic correlations and causal relationships is currently unclear. We applied Genomic Structural Equation Modelling (GSEM) to dissect the genetic architecture between loneliness and psychiatric-behavioural traits. Included were summary statistics from 12 genome-wide association analyses, including loneliness and 11 psychiatric phenotypes (range N: 9,537 - 807,553). We first modelled latent genetic factors amongst the psychiatric traits to then investigate potential causal effects between loneliness and the identified latent factors, using multivariate genome-wide association analyses and bidirectional Mendelian randomization. We identified three latent genetic factors, encompassing neurodevelopmental/mood conditions, substance use traits and disorders with psychotic features. GSEM provided evidence of a unique association between loneliness and the neurodevelopmental/mood conditions latent factor. Mendelian randomization results were suggestive of bidirectional causal effects between loneliness and the neurodevelopmental/mood conditions factor. These results imply that a genetic predisposition to loneliness may elevate the risk of neurodevelopmental/mood conditions, and vice versa. However, results may reflect the difficulty of distiguishing between loneliness and neurodevelopmental/mood conditions, which present in similar ways. We suggest, overall, the importance of addressing loneliness in mental health prevention and policy.


Subject(s)
Mental Disorders , Substance-Related Disorders , Humans , Genome-Wide Association Study , Loneliness , Mental Disorders/epidemiology , Mental Disorders/genetics , Phenotype , Substance-Related Disorders/epidemiology , Substance-Related Disorders/genetics , Polymorphism, Single Nucleotide
6.
Eur J Sport Sci ; 20(6): 813-818, 2020 Jul.
Article in English | MEDLINE | ID: mdl-31578132

ABSTRACT

Research suggests that caffeine can enhance measures of muscular strength in the upper and lower extremities, although the literature is somewhat equivocal. Little is known on whether or not caffeine will improve maximal inspiratory pressure (MIP), a surrogate measure of inspiratory muscle strength. The purpose of the study was to determine the effects of a moderate dose of caffeine on inspiratory muscle function. Fifteen (8 male, 7 female) healthy adults (mean ± SD: age = 24.3 ± 6.4 years; height = 1.75 ± 0.11 m; body mass = 78.8 ± 16.5 kg) volunteered to participate in the study which used a double-blind, placebo-controlled, cross-over design. During the initial visit, baseline data was collected and participants were familiarized with inspiratory muscle measurements. For the second and third visits, participants ingested either a 5 mg kg-1 dose of caffeine (CAF) or placebo capsule (PL). After one hour, they completed at least 12 maximal inspiratory manoeuvres with 1 min rest between each attempt. MIP, maximal inspiratory peak pressure (PP), and maximal rate of pressure development (MRPD) were recorded. The CAF trial resulted in significantly higher MIP (154.7 ± 35.8 vs. 146.6 ± 37.6 cmH2O; p = 0.02) and PP (165.8 ± 36.8 vs. 158.3 cmH2O; p = 0.01) compared to the PL condition. No significant difference was observed in MRPD (p = 0.18). MIP and PP improved after ingestion of caffeine compared to the placebo condition. The findings from the study further establish caffeine's potential ergogenic benefit on measures of muscular strength.


Subject(s)
Caffeine/pharmacology , Diaphragm/drug effects , Muscle Strength/drug effects , Performance-Enhancing Substances/pharmacology , Adult , Cross-Over Studies , Diaphragm/physiology , Double-Blind Method , Female , Humans , Inhalation , Male , Muscle Strength/physiology , Placebos , Young Adult
7.
J Biomech ; 99: 109507, 2020 01 23.
Article in English | MEDLINE | ID: mdl-31780121

ABSTRACT

Ladder slip and falls cause negative financial and health impacts due to their severity and frequency. However, frictional requirements of climbing, which presumably influence slip risk, are unknown. The purpose of this study was to quantify frictional requirements during climbing at different ladder angles. The required coefficient of friction (RCOF) was calculated during ladder climbing and assessed for three ladder angles (75.5°, 82.8°, and 90°). Data was collected from 10 participants at each angle. Kinetic data and kinematic data of the climber's shoe was collected and used to map friction and normal forces to the shoe. These forces were then used to calculate the RCOF. The RCOF and friction force at 90° was higher than at lower angles (75.5° and 82.8°). RCOF was correlated with shoe angle and body angle supporting both the relevance of shoe orientation and body position to slip risk. This study suggests that frictional requirements of ladder climbing are dependent on ladder angle, shoe orientation, and body angle.


Subject(s)
Friction , Shoes , Walking/physiology , Accidental Falls , Adult , Biomechanical Phenomena , Female , Humans , Male , Posture
8.
Am J Gastroenterol ; 114(6): 984-994, 2019 06.
Article in English | MEDLINE | ID: mdl-31008735

ABSTRACT

OBJECTIVES: The literature related to eosinophilic gastritis (EG), gastroenteritis (EGE), and colitis (EC) is limited. We aimed to characterize rates of diagnosis, clinical features, and initial treatments for patients with EG, EGE, and EC. METHODS: In this retrospective study, data were collected from 6 centers in the Consortium of Eosinophilic Gastrointestinal Researchers from 2005 to 2016. We analyzed demographics, time trends in diagnosis, medical history, presenting symptoms, disease overlap, and initial treatment patterns/responses. RESULTS: Of 373 subjects (317 children and 56 adults), 38% had EG, 33% EGE, and 29% EC. Rates of diagnosis of all diseases increased over time. There was no male predominance, and the majority of subjects had atopy. Presenting symptoms were similar between diseases with nausea/vomiting and abdominal pain, the most common. One hundred fifty-four subjects (41%) had eosinophilic inflammation outside of their primary disease location with the esophagus the second most common gastrointestinal (GI) segment involved. Multisite inflammation was more common in children than in adults (68% vs 37%; P < 0.001). Initial treatment patterns varied highly between centers. One hundred-nine subjects (29%) had follow-up within 6 months, and the majority had clinical, endoscopic, and histologic improvements. CONCLUSIONS: In this cohort, EG, EGE, and EC were diagnosed more frequently over time, and inflammation of GI segments outside the primary disease site co-occurrence of atopy was common with a lack of male predominance. Symptoms were similar between diseases, and initial treatment strategies were highly variable. Future investigation should assess the cause of the increased prevalence of eosinophilic GI disorders and prospectively assess outcomes to establish treatment algorithms.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Colitis/epidemiology , Enteritis/epidemiology , Eosinophilia/epidemiology , Eosinophils/pathology , Gastritis/epidemiology , Gastroenteritis/epidemiology , Gastrointestinal Agents/therapeutic use , Intestinal Mucosa/pathology , Adolescent , Adult , Child , Child, Preschool , Colitis/diagnosis , Colitis/drug therapy , Comorbidity/trends , Enteritis/diagnosis , Enteritis/drug therapy , Eosinophilia/diagnosis , Eosinophilia/drug therapy , Female , Follow-Up Studies , Forecasting , Gastritis/diagnosis , Gastritis/drug therapy , Gastroenteritis/diagnosis , Gastroenteritis/drug therapy , Humans , Incidence , Infant , Male , Middle Aged , Retrospective Studies , United States/epidemiology , Young Adult
14.
Health Soc Work ; 40(3): 191-200, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26285358

ABSTRACT

This article describes the development of an integrated psychosocial patient and caregiver assessment and plan of care for hospice social work documentation. A team of hospice social workers developed the Social Work Assessment Notes as a quality improvement project in collaboration with the information technology department. Using the Social Work Assessment Tool as an organizing framework, this comprehensive hospice social work documentation system is designed to integrate assessment, planning, and outcomes measurement. The system was developed to guide the assessment of patients' and caregivers' needs related to end-of-life psychosocial issues, to facilitate collaborative care plan development, and to measure patient- and family-centered outcomes. Goals established with the patient and the caregiver are documented in the plan of care and become the foundation for patient-centered, strengths-based interventions. Likert scales are used to assign numerical severity levels for identified issues and progress made toward goals and to track the outcome of social work interventions across nine psychosocial constructs. The documentation system was developed for use in an electronic health record but can be used for paper charting. Future plans include automated aggregate outcomes measurement to identify the most effective interventions and best practices in end-of-life care.


Subject(s)
Documentation/standards , Hospice Care , Outcome and Process Assessment, Health Care , Planning Techniques , Quality Improvement , Social Work , Terminal Care , Humans , Needs Assessment
15.
Nat Commun ; 6: 7587, 2015 Jun 29.
Article in English | MEDLINE | ID: mdl-26119338

ABSTRACT

Warming of high northern latitudes in the Pliocene (5.33-2.58 Myr ago) has been linked to the closure of the Central American Seaway and intensification of North Atlantic Deep Water. Subsequent cooling in the late Pliocene may be related to the effects of freshwater input from the Arctic Ocean via the Bering Strait, disrupting North Atlantic Deep Water formation and enhancing sea ice formation. However, the timing of Arctic freshening has not been defined. Here we present neodymium and lead isotope records of detrital sediment from the Bering Sea for the past 4.3 million years. Isotopic data suggest the presence of Alaskan glaciers as far back as 4.2 Myr ago, while diatom and C37:4 alkenone records show a long-term trend towards colder and fresher water in the Bering Sea beginning with the M2 glaciation (3.3 Myr ago). We argue that the introduction of low-salinity Bering Sea water to the Arctic Ocean by 3.3 Myr ago preconditioned the climate system for global cooling.

17.
Nature ; 517(7532): 30-1, 2015 Jan 01.
Article in English | MEDLINE | ID: mdl-25517092

Subject(s)
Ice Cover , Water Movements
19.
Comput Inform Nurs ; 31(6): 257-65, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23681256

ABSTRACT

Meta-analyses of broad scope and complexity require investigators to organize many study documents and manage communication among several research staff. Commercially available electronic tools, for example, EndNote, Adobe Acrobat Pro, Blackboard, Excel, and IBM SPSS Statistics (SPSS), are useful for organizing and tracking the meta-analytic process as well as enhancing communication among research team members. The purpose of this article is to describe the electronic processes designed, using commercially available software, for an extensive, quantitative model-testing meta-analysis. Specific electronic tools improved the efficiency of (a) locating and screening studies, (b) screening and organizing studies and other project documents, (c) extracting data from primary studies, (d) checking data accuracy and analyses, and (e) communication among team members. The major limitation in designing and implementing a fully electronic system for meta-analysis was the requisite upfront time to decide on which electronic tools to use, determine how these tools would be used, develop clear guidelines for their use, and train members of the research team. The electronic process described here has been useful in streamlining the process of conducting this complex meta-analysis and enhancing communication and sharing documents among research team members.


Subject(s)
Medical Informatics , Clinical Coding
20.
Science ; 312(5772): 428-30, 2006 Apr 21.
Article in English | MEDLINE | ID: mdl-16627741

ABSTRACT

Age estimates for the opening of Drake Passage range from 49 to 17 million years ago (Ma), complicating interpretations of the relationship between ocean circulation and global cooling. Secular variations of neodymium isotope ratios at Agulhas Ridge (Southern Ocean, Atlantic sector) suggest an influx of shallow Pacific seawater approximately 41 Ma. The timing of this connection and the subsequent deepening of the passage coincide with increased biological productivity and abrupt climate reversals. Circulation/productivity linkages are proposed as a mechanism for declining atmospheric carbon dioxide. These results also indicate that Drake Passage opened before the Tasmanian Gateway, implying the late Eocene establishment of a complete circum-Antarctic pathway.

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