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1.
Proc Natl Acad Sci U S A ; 121(21): e2313599121, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38739790

RESUMO

The ecoevolutionary drivers of species niche expansion or contraction are critical for biodiversity but challenging to infer. Niche expansion may be promoted by local adaptation or constrained by physiological performance trade-offs. For birds, evolutionary shifts in migratory behavior permit the broadening of the climatic niche by expansion into varied, seasonal environments. Broader niches can be short-lived if diversifying selection and geography promote speciation and niche subdivision across climatic gradients. To illuminate niche breadth dynamics, we can ask how "outlier" species defy constraints. Of the 363 hummingbird species, the giant hummingbird (Patagona gigas) has the broadest climatic niche by a large margin. To test the roles of migratory behavior, performance trade-offs, and genetic structure in maintaining its exceptional niche breadth, we studied its movements, respiratory traits, and population genomics. Satellite and light-level geolocator tracks revealed an >8,300-km loop migration over the Central Andean Plateau. This migration included a 3-wk, ~4,100-m ascent punctuated by upward bursts and pauses, resembling the acclimatization routines of human mountain climbers, and accompanied by surging blood-hemoglobin concentrations. Extreme migration was accompanied by deep genomic divergence from high-elevation resident populations, with decisive postzygotic barriers to gene flow. The two forms occur side-by-side but differ almost imperceptibly in size, plumage, and respiratory traits. The high-elevation resident taxon is the world's largest hummingbird, a previously undiscovered species that we describe and name here. The giant hummingbirds demonstrate evolutionary limits on niche breadth: when the ancestral niche expanded due to evolution (or loss) of an extreme migratory behavior, speciation followed.


Assuntos
Migração Animal , Aves , Especiação Genética , Animais , Migração Animal/fisiologia , Aves/genética , Aves/fisiologia , Aves/classificação , Ecossistema , Altitude , Evolução Biológica
3.
Oecologia ; 195(2): 435-451, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33484348

RESUMO

Turnover in species composition between sites, or beta diversity, is a critical component of species diversity that is typically influenced by geography, environment, and biotic interactions. Quantifying turnover is particularly challenging, however, in multi-host, multi-parasite assemblages where undersampling is unavoidable, resulting in inflated estimates of turnover and uncertainty about its spatial scale. We developed and implemented a framework using null models to test for community turnover in avian haemosporidian communities of three sky islands in the southwestern United States. We screened 776 birds for haemosporidian parasites from three genera (Parahaemoproteus, Plasmodium, and Leucocytozoon) by amplifying and sequencing a mitochondrial DNA barcode. We detected infections in 280 birds (36.1%), sequenced 357 infections, and found a total of 99 parasite haplotypes. When compared to communities simulated from a regional pool, we observed more unique, single-mountain haplotypes and fewer haplotypes shared among three mountain ranges than expected, indicating that haemosporidian communities differ to some degree among adjacent mountain ranges. These results were robust even after pruning datasets to include only identical sets of host species, and they were consistent for two of the three haemosporidian genera. The two more distant mountain ranges were more similar to each other than the one located centrally, suggesting that the differences we detected were due to stochastic colonization-extirpation dynamics. These results demonstrate that avian haemosporidian communities of temperate-zone forests differ on relatively fine spatial scales between adjacent sky islands. Null models are essential tools for testing the spatial scale of turnover in complex, undersampled, and poorly known systems.


Assuntos
Doenças das Aves , Haemosporida , Parasitos , Plasmodium , Animais , Haemosporida/genética , Ilhas , Filogenia , Sudoeste dos Estados Unidos
4.
Int J Parasitol ; 49(6): 437-448, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30910465

RESUMO

Haemosporidian parasites of birds are ubiquitous in terrestrial ecosystems, but their coevolutionary dynamics remain poorly understood. If species turnover in parasites occurs at a finer scale than turnover in hosts, widespread hosts would encounter diverse parasites, potentially diversifying as a result. Previous studies have shown that some wide-ranging hosts encounter varied haemosporidian communities throughout their range, and vice-versa. More surveys are needed to elucidate mechanisms that underpin spatial patterns of diversity in this complex multi-host multi-parasite system. We sought to understand how and why a community of avian haemosporidian parasites varies in abundance and composition across elevational transects in eight sky islands in southwestern North America. We tested whether bird community composition, environment, or geographic distance explain haemosporidian parasite species turnover in a widespread host that harbors a diverse haemosporidian community, the Audubon's Warbler (Setophaga auduboni). We tested predictors of infection using generalized linear models, and predictors of bird and parasite community dissimilarity using generalized dissimilarity modeling. Predictors of infection differed by parasite genus: Parahaemoproteus was predicted by elevation and climate, Leucocytozoon varied idiosyncratically among mountains, and Plasmodium was unpredictable, but rare. Parasite turnover was nearly three-fold higher than bird turnover and was predicted by elevation, climate, and bird community composition, but not geographic distance. Haemosporidian communities vary strikingly at fine spatial scales (hundreds of kilometers), across which the bird community varies only subtly. The finer scale of turnover among parasites implies that their ranges may be smaller than those of their hosts. Avian host species should encounter different parasite species in different parts of their ranges, resulting in spatially varying selection on host immune systems. The fact that parasite turnover was predicted by bird turnover, even when considering environmental characteristics, implies that host species or their phylogenetic history plays a role in determining which parasite species will be present in a community.


Assuntos
Doenças das Aves/parasitologia , Haemosporida/fisiologia , Infecções Protozoárias em Animais/parasitologia , Aves Canoras/parasitologia , Altitude , Animais , Distribuição Binomial , Biodiversidade , Intervalos de Confiança , DNA de Protozoário/isolamento & purificação , Clima Desértico , Florestas , Haemosporida/classificação , Haplótipos , Funções Verossimilhança , Modelos Lineares , Dinâmica não Linear , Filogenia , Infecções Protozoárias em Animais/epidemiologia , Análise de Regressão , Sudoeste dos Estados Unidos , Análise Espacial
5.
PeerJ ; 5: e3700, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28828279

RESUMO

Avian malaria and related haemosporidian parasites (genera Haemoproteus, Plasmodium, and Leucocytozoon) affect bird demography, species range limits, and community structure, yet they remain unsurveyed in most bird communities and populations. We conducted a community-level survey of these vector-transmitted parasites in New Mexico, USA, to describe their diversity, abundance, and host associations. We focused on the breeding-bird community in the transition zone between piñon-juniper woodland and ponderosa pine forests (elevational range: 2,150-2,460 m). We screened 186 birds representing 49 species using both standard PCR and microscopy techniques to detect infections of all three avian haemosporidian genera. We detected infections in 68 out of 186 birds (36.6%), the highest proportion of which were infected with Haemoproteus (20.9%), followed by Leucocytozoon (13.4%), then Plasmodium (8.0%). We sequenced mtDNA for 77 infections representing 43 haplotypes (25 Haemoproteus, 12 Leucocytozoon, 6 Plasmodium). When compared to all previously known haplotypes in the MalAvi and GenBank databases, 63% (27) of the haplotypes we recovered were novel. We found evidence for host specificity at the avian clade and species level, but this specificity was variable among parasite genera, in that Haemoproteus and Leucocytozoon were each restricted to three avian groups (out of six), while Plasmodium occurred in all groups except non-passerines. We found striking variation in infection rate among host species, with nearly universal infection among vireos and no infection among nuthatches. Using rarefaction and extrapolation, we estimated the total avian haemosporidian diversity to be 70 haplotypes (95% CI [43-98]); thus, we may have already sampled ∼60% of the diversity of avian haemosporidians in New Mexico pine forests. It is possible that future studies will find higher diversity in microhabitats or host species that are under-sampled or unsampled in the present study. Fortunately, this study is fully extendable via voucher specimens, frozen tissues, blood smears, parasite images, and documentation provided in open-access databases (MalAvi, GenBank, and ARCTOS).

6.
J Hand Ther ; 30(3): 359-366, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28341324

RESUMO

STUDY DESIGN: Prospective, repeated-measures study. INTRODUCTION: Understanding individual hand function can assist therapists with the process of determining relevant treatment approaches and realistic therapeutic outcomes. At this point in time, a composite test that assesses both unilateral and bimanual hand function in relation to a functional activity is not available. PURPOSE OF THE STUDY: To establish the reliability and validity of the suitcase packing activity (SPA). METHODS: An expert panel established face and content validity. Eighty healthy, English-speaking volunteers aged between 18 and 45 years were randomly assigned to either 1 or 2 sessions (test-retest reliability). Relative agreement between 2 examiners using an intraclass correlation coefficient (ICC)3,1 determined interrater reliability. Test-retest reliability was determined by using a repeated-measures analysis of variance and an ICC3,2. Concurrent validity was evaluated against 2 well-established hand evaluations using separate tests of correlational coefficients. RESULTS: Face and content validity were established across 4 focus groups. Our results demonstrate good to excellent interrater reliability (ICC3,1 ≥ 0.93) and good to excellent test-retest reliability (ICC3,2 ≥ 0.83). SPA scores were moderately correlated with the 2-hand evaluations. DISCUSSION: Through evaluating hand function during participation in a goal-directed activity (eg, packing a suitcase), the SPA exhibits promise in usefulness as a future viable outcome measure that can be used to assess functional abilities following a hand injury. CONCLUSION: The SPA is a valid and reliable tool for assessing bimanual and unilateral hand function in healthy subjects. LEVELS OF EVIDENCE: Diagnostic level II.

7.
Proc Natl Acad Sci U S A ; 114(2): E122-E131, 2017 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-28028223

RESUMO

Climate change in the circumpolar region is causing dramatic environmental change that is increasing the vulnerability of infrastructure. We quantified the economic impacts of climate change on Alaska public infrastructure under relatively high and low climate forcing scenarios [representative concentration pathway 8.5 (RCP8.5) and RCP4.5] using an infrastructure model modified to account for unique climate impacts at northern latitudes, including near-surface permafrost thaw. Additionally, we evaluated how proactive adaptation influenced economic impacts on select infrastructure types and developed first-order estimates of potential land losses associated with coastal erosion and lengthening of the coastal ice-free season for 12 communities. Cumulative estimated expenses from climate-related damage to infrastructure without adaptation measures (hereafter damages) from 2015 to 2099 totaled $5.5 billion (2015 dollars, 3% discount) for RCP8.5 and $4.2 billion for RCP4.5, suggesting that reducing greenhouse gas emissions could lessen damages by $1.3 billion this century. The distribution of damages varied across the state, with the largest damages projected for the interior and southcentral Alaska. The largest source of damages was road flooding caused by increased precipitation followed by damages to buildings associated with near-surface permafrost thaw. Smaller damages were observed for airports, railroads, and pipelines. Proactive adaptation reduced total projected cumulative expenditures to $2.9 billion for RCP8.5 and $2.3 billion for RCP4.5. For road flooding, adaptation provided an annual savings of 80-100% across four study eras. For nearly all infrastructure types and time periods evaluated, damages and adaptation costs were larger for RCP8.5 than RCP4.5. Estimated coastal erosion losses were also larger for RCP8.5.

8.
Front Public Health ; 4: 272, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28018897

RESUMO

BACKGROUND/AIMS: This study's objective was to evaluate a patient-centered educational electronic tablet application, "My Interventional Drug-Eluting Stent Educational App" (MyIDEA) to see if there was an increase in patient knowledge about dual antiplatelet therapy (DAPT) and medication possession ratio (MPR) compared to treatment as usual. METHODS: In a pilot project, 24 elderly (≥50 years old) research participants were recruited after a drug-eluting stent. Eleven were randomized to the control arm and 13 to the interventional arm. All the participants completed psychological and knowledge questionnaires. Adherence was assessed through MPR, which was calculated at 3 months for all participants who were scheduled for second and third follow-up visits. RESULTS: Relative to control, the interventional group had a 10% average increase in MPR. As compared to the interventional group, more patients in the control group had poor adherence (<80% MPR). The psychological data revealed a single imbalance in anxiety between the control and interventional groups. On average, interventional participants spent 21 min using MyIDEA. DISCUSSION: Consumer health informatics has enabled us to engage patients with their health data using novel methods. Consumer health technology needs to focus more on patient knowledge and engagement to improve long-term health. MyIDEA takes a unique approach in targeting DAPT from the onset. CONCLUSION: MyIDEA leverages patient-centered information with clinical care and the electronic health record highlighting the patients' role as a team member in their own health care. The patients think critically about adverse events and how to solve issues before leaving the hospital.

10.
JMIR Mhealth Uhealth ; 3(3): e74, 2015 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-26139587

RESUMO

BACKGROUND: Patient adherence to medication regimens is critical in most chronic disease treatment plans. This study uses a patient-centered tablet app, "My Interventional Drug-Eluting Stent Educational App (MyIDEA)." This is an educational program designed to improve patient medication adherence. OBJECTIVE: Our goal is to describe the design, methodology, limitations, and results of the MyIDEA tablet app. We created a mobile technology-based patient education app to improve dual antiplatelet therapy adherence in patients who underwent a percutaneous coronary intervention and received a drug-eluting stent. METHODS: Patient advisers were involved in the development process of MyIDEA from the initial wireframe to the final launch of the product. The program was restructured and redesigned based on the patient advisers' suggestions as well as those from multidisciplinary team members. To accommodate those with low health literacy, we modified the language and employed attractive color schemes to improve ease of use. We assumed that the target patient population may have little to no experience with electronic tablets, and therefore, we designed the interface to be as intuitive as possible. RESULTS: The MyIDEA app has been successfully deployed to a low-health-literate elderly patient population in the hospital setting. A total of 6 patients have interacted with MyIDEA for an average of 17.6 minutes/session. CONCLUSIONS: Including patient advisers in the early phases of a mobile patient education development process is critical. A number of changes in text order, language, and color schemes occurred to improve ease of use. The MyIDEA program has been successfully deployed to a low-health-literate elderly patient population. Leveraging patient advisers throughout the development process helps to ensure implementation success.

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