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2.
J Anim Ecol ; 87(5): 1484-1496, 2018 09.
Article in English | MEDLINE | ID: mdl-29782655

ABSTRACT

Fire creates challenges and opportunities for wildlife through rapid destruction, modification and creation of habitat. Fire has spatially variable effects on landscapes; however, for species that benefit from the ephemeral resource patches created by fire, it is critical to understand characteristics of fires that promote postfire colonization and persistence and the spatial scales on which they operate. Using a model postfire specialist, the black-backed woodpecker (Picoides arcticus), we examined how colonization and persistence varied across two spatial scales as a function of four characteristics of fire regimes-fire severity, fire size, fire ignition date and number of years since fire. We modelled black-backed woodpecker colonization and persistence using data from 108 recently burned forests in the Sierra Nevada and southern Cascades ecoregions of California, USA, that we monitored for up to 10 years following fire. We employed a novel, spatially hierarchical, dynamic occupancy framework which differentiates colonization and persistence at two spatial scales: across fires and within fires. We found strong effects of fire characteristics on dynamic rates, with colonization and persistence declining across both spatial scales with increasing years since fire. Additionally, at sites within fires, colonization decreased with fire size and increased with fire severity and for fires with later ignition dates. Our results support the notion that different aspects of a species' environment are important for population processes at different spatial scales. As habitat quality is ephemeral for any given postfire area, our results illustrate the importance of time since fire in structuring occupancy at the fire level, with other characteristics of fires playing larger roles in determining abundance within individual fires. Our results contribute to the broader understanding of how variation in fire characteristics influences the colonization and persistence of species using ephemeral habitats, which is necessary for conserving and promoting postfire biodiversity in the context of rapidly shifting fire regimes.


Subject(s)
Fires , Animals , California , Ecosystem , Forests , Nevada
3.
Proc Biol Sci ; 283(1840)2016 Oct 12.
Article in English | MEDLINE | ID: mdl-27708152

ABSTRACT

An emerging hypothesis in fire ecology is that pyrodiversity increases species diversity. We test whether pyrodiversity-defined as the standard deviation of fire severity-increases avian biodiversity at two spatial scales, and whether and how this relationship may change in the decade following fire. We use a dynamic Bayesian community model applied to a multi-year dataset of bird surveys at 1106 points sampled across 97 fires in montane California. Our results provide strong support for a positive relationship between pyrodiversity and bird diversity. This relationship interacts with time since fire, with pyrodiversity having a greater effect on biodiversity at 10 years post-fire than at 1 year post-fire. Immediately after fires, patches of differing burn severities hold similar bird communities, but over the ensuing decade, bird assemblages within patches of contrasting severities differentiate. When evaluated at the scale of individual fires, fires with a greater heterogeneity of burn severities hold substantially more species. High spatial heterogeneity in severity, sometimes called 'mixed-severity fire', is a natural part of wildfire regimes in western North America, but may be jeopardized by climate change and a legacy of fire suppression. Forest management that encourages mixed-severity fire may be critical for sustaining biodiversity across fire-prone landscapes.


Subject(s)
Biodiversity , Birds/classification , Fires , Forests , Animals , Bayes Theorem , California , Climate Change
4.
Gerontologist ; 55(4): 719-29, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26179707

ABSTRACT

PURPOSE OF THE STUDY: Artistic engagement has been identified as a promising way to improve older adults' quality of life (QoL) and health. This has resulted in a growing, yet diverse, knowledge base. The purpose of this scoping review was to describe and map the nature and extent of research conducted on the arts, aging, and either QoL or health for well older adults. DESIGN AND METHODS: We followed scoping review procedures. Research librarians developed a comprehensive search strategy to capture published and gray literature across 16 databases. We systematically screened 9,720 titles/abstracts and extracted data. Findings were collated by tabulating frequencies and textual data organized according to themes. RESULTS: 94 articles were included, spanning nine disciplines, and most were published after 2000 (72%). Most of the studies were conducted in the United States (52%). Research teams rarely published more than one study about the arts and QoL/health. The studies used qualitative (49%), quantitative (38%), or mixed methods (10%). The most common art form examined was music (40%). Artistic engagement was usually active (70%) and frequently occurred in groups (56%). Health and QoL were conceptualized and operationalized in many different ways. IMPLICATIONS: There is a need for programs of research (instead of teams conducting only one study), the development and application of conceptual frameworks, and multiple perspectives in order to build knowledge about how the arts contribute to health and QoL for older adults.


Subject(s)
Aging/psychology , Art , Creativity , Quality of Life , Aged , Health Status , Humans , Music
5.
PLoS One ; 10(4): e0125198, 2015.
Article in English | MEDLINE | ID: mdl-25915801

ABSTRACT

To evaluate the current status of the western population of the Yellow-billed Cuckoo (Coccyzus americanus) along the Sacramento and Feather rivers in California's Sacramento Valley, we conducted extensive call playback surveys in 2012 and 2013. We also quantified the amount and distribution of potential habitat. Our survey transects were randomly located and spatially balanced to sample representative areas of the potential habitat. We estimated that the total area of potential habitat was 8,134 ha along the Sacramento River and 2,052 ha along the Feather River, for a total of 10,186 ha. Large-scale restoration efforts have created potential habitat along both of these rivers. Despite this increase in the amount of habitat, the number of cuckoos we detected was extremely low. There were 8 detection occasions in 2012 and 10 occasions in 2013 on the Sacramento River, in both restored and remnant habitat. We had no detections on the Feather River in either year. We compared our results to 10 historic studies from as far back as 1972 and found that the Yellow-billed Cuckoo had unprecedentedly low numbers in 2010, 2012, and 2013. The current limiting factor for the Yellow-billed Cuckoo in the Sacramento Valley is likely not the amount of appropriate vegetation, as restoration has created more habitat over the last 30 years. Reasons for the cuckoo decline on the Sacramento and Feather rivers are unclear.


Subject(s)
Birds , Animals , California , Demography , Ecosystem , Rivers
6.
Conserv Biol ; 26(3): 482-92, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22443304

ABSTRACT

Monitoring responses by birds to restoration of riparian vegetation is relatively cost-effective, but in most assessments species-specific abundances, not demography, are monitored. Data on birds collected during the nonbreeding season are particularly lacking. We captured birds in mist nets and resighted banded birds to estimate species richness and diversity, abundance, demographic indexes, and site-level persistence of permanent-resident and overwintering migrants in remnant and restored riparian sites in California. Species richness in riparian remnants was significantly higher than in restored sites because abundances of uncommon permanent residents were greater in remnants. Species richness of overwintering migrants did not differ between remnants and restored sites. Responses among overwintering migrants (but not permanent residents) to remnant and restored riparian sites differed. Capture rates were higher in remnant or restored riparian sites for 7 of 10 overwintering migratory species. For Lincoln's Sparrows (Melospiza lincolnii) and White-crowned Sparrows (Zonotrichia leucophrys) proportions of older birds were significantly higher in remnants, even though capture rates of these species were higher in restored sites. Overwinter persistence of 4 migrant species was significantly higher in remnant than in restored sites. A higher proportion of Hermit Thrushes (Catharus guttatus, 56.3%), older Fox Sparrows (Passerella iliaca, 57.1%), Lincoln's Sparrows (59.7%), and White-crowned Sparrows (67.8%) persisted in remnants than restored sites. Our results suggest restored riparian sites provide habitat for a wide variety of species in comparable abundances and diversity as occurs in remnant riparian sites. Our demographic and persistence data showed that remnants supported some species and age classes to a greater extent than restored sites.


Subject(s)
Biota , Conservation of Natural Resources , Ecosystem , Songbirds/physiology , Animal Migration , Animals , California , Seasons
7.
Proc Natl Acad Sci U S A ; 106 Suppl 2: 19729-36, 2009 Nov 17.
Article in English | MEDLINE | ID: mdl-19822750

ABSTRACT

As the rate and magnitude of climate change accelerate, understanding the consequences becomes increasingly important. Species distribution models (SDMs) based on current ecological niche constraints are used to project future species distributions. These models contain assumptions that add to the uncertainty in model projections stemming from the structure of the models, the algorithms used to translate niche associations into distributional probabilities, the quality and quantity of data, and mismatches between the scales of modeling and data. We illustrate the application of SDMs using two climate models and two distributional algorithms, together with information on distributional shifts in vegetation types, to project fine-scale future distributions of 60 California landbird species. Most species are projected to decrease in distribution by 2070. Changes in total species richness vary over the state, with large losses of species in some "hotspots" of vulnerability. Differences in distributional shifts among species will change species co-occurrences, creating spatial variation in similarities between current and future assemblages. We use these analyses to consider how assumptions can be addressed and uncertainties reduced. SDMs can provide a useful way to incorporate future conditions into conservation and management practices and decisions, but the uncertainties of model projections must be balanced with the risks of taking the wrong actions or the costs of inaction. Doing this will require that the sources and magnitudes of uncertainty are documented, and that conservationists and resource managers be willing to act despite the uncertainties. The alternative, of ignoring the future, is not an option.


Subject(s)
Algorithms , Biodiversity , Birds/physiology , Models, Biological , Animals , California
8.
PLoS One ; 4(9): e6825, 2009 Sep 02.
Article in English | MEDLINE | ID: mdl-19724641

ABSTRACT

By facilitating independent shifts in species' distributions, climate disruption may result in the rapid development of novel species assemblages that challenge the capacity of species to co-exist and adapt. We used a multivariate approach borrowed from paleoecology to quantify the potential change in California terrestrial breeding bird communities based on current and future species-distribution models for 60 focal species. Projections of future no-analog communities based on two climate models and two species-distribution-model algorithms indicate that by 2070 over half of California could be occupied by novel assemblages of bird species, implying the potential for dramatic community reshuffling and altered patterns of species interactions. The expected percentage of no-analog bird communities was dependent on the community scale examined, but consistent geographic patterns indicated several locations that are particularly likely to host novel bird communities in the future. These no-analog areas did not always coincide with areas of greatest projected species turnover. Efforts to conserve and manage biodiversity could be substantially improved by considering not just future changes in the distribution of individual species, but including the potential for unprecedented changes in community composition and unanticipated consequences of novel species assemblages.


Subject(s)
Birds/physiology , Climate Change , Algorithms , Animals , Biodiversity , California , Climate , Conservation of Natural Resources , Ecosystem , Extinction, Biological , Geography , Multivariate Analysis , Population Dynamics , Probability , Species Specificity , Temperature
9.
Crit Care Nurs Clin North Am ; 18(4): 523-9, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17118307

ABSTRACT

The ACNP service in this study decreased the TA, TC, and LOS for patients transferred from outlying hospitals for cardiac catheterization or PCI. Patients on the ACNP service were provided prescription for appropriate discharge medications including beta-blockers, aspirin, ACE inhibitors, and lipid-lowering agents more often than patients on the housestaff service. Other aspects of care, including follow-up appointments and elements of patient education, were documented more often for patients on the ACNP interventional cardiac service and expand the role of ACNPs into other areas of acute-care cardiology practice.


Subject(s)
Angioplasty, Balloon, Coronary/nursing , Cardiac Catheterization/nursing , Nurse Practitioners/organization & administration , Nurse's Role , Cooperative Behavior , Cost-Benefit Analysis , Female , Humans , Length of Stay/statistics & numerical data , Male , Middle Aged , Multivariate Analysis , Nursing Evaluation Research , Outcome Assessment, Health Care , Patient Admission , Patient Discharge/standards , Patient Education as Topic/standards , Patient Selection , Physician-Nurse Relations , Professional Autonomy , Program Evaluation , Retrospective Studies , Time Factors
10.
J Cardiovasc Nurs ; 20(4): 271-5, 2005.
Article in English | MEDLINE | ID: mdl-16000916

ABSTRACT

Despite medical therapy, the overall prognosis for heart failure (HF) remains poor with high rates of sudden death and death from progressive HF. Device-based therapies offer considerable promise both for the relief of symptoms and for improving prognosis. Cardiac resynchronization therapy is a relatively new and effective treatment for patients with moderate to severe systolic HF and ventricular dyssynchrony. Clinical trials have demonstrated an improvement in quality of life, improved exercise tolerance, decreased HF hospitalizations, and improved survival. Complication rates for patients receiving cardiac pacemakers are relatively low. Although rare, cardiac tamponade caused by myocardial perforation during pacing lead insertion usually occurs a short time after the procedure. This case study discusses a patient who presented with cardiac tamponade 4 months after pacemaker implant. A small perforation of the right atrial lead caused a slow effusion into the pericardial sac. The patient's unusual presentation, hospital course, pathophysiology, and treatment for cardiac tamponade are discussed.


Subject(s)
Cardiac Tamponade/etiology , Heart Atria/injuries , Pacemaker, Artificial/adverse effects , Pericardial Effusion/etiology , Female , Heart Injuries/diagnosis , Heart Injuries/surgery , Humans , Middle Aged , Reoperation
11.
Aging Cell ; 2(2): 123-30, 2003 04.
Article in English | MEDLINE | ID: mdl-12882325

ABSTRACT

Molecular advances of the past decade have led to the discovery of a myriad of 'aging genes' (methuselah, Indy, InR, Chico, superoxide dismutase) that extend Drosophila lifespan by up to 85%. Despite this life extension, these mutants are no longer lived than at least some recently wild-caught strains. Typically, long-lived mutants are identified in relatively short-lived genetic backgrounds, and their effects are rarely tested in genetic backgrounds other than the one in which they were isolated or derived. However, the mutant's high-longevity phenotype may be dependent on interactions with alleles that are common in short-lived laboratory strains. Here we set out to determine whether one particular mutant could extend lifespan in long-lived genetic backgrounds in the fruit fly, Drosophila melanogaster. We measured longevity and resistance to thermal stress in flies that were transgenically altered to overexpress human superoxide dismutase (SOD) in the motorneurones in each of 10 genotypes. Each genotype carried the genetic background from a different naturally long-lived wild-caught Drosophila strain. While SOD increased lifespan on average, the effect was genotype- and sex-specific. Our results indicate that naturally segregating genes interact epistatically with the aging gene superoxide dismutase to modify its ability to extend longevity. This study points to the need to identify mutants that increase longevity not only in the lab strain of origin but also in naturally long-lived genetic backgrounds.


Subject(s)
Aging/genetics , Drosophila melanogaster/genetics , Genes, Insect , Longevity/genetics , Superoxide Dismutase/physiology , Animals , Animals, Genetically Modified , Crosses, Genetic , Drosophila melanogaster/physiology , Epistasis, Genetic , Female , Hot Temperature , Humans , Male , Motor Neurons/enzymology , Nerve Tissue Proteins/physiology , Phenotype , Recombinant Fusion Proteins/physiology , Sex Characteristics , Stress, Physiological , Superoxide Dismutase/genetics , Superoxide Dismutase-1
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