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Environmental gradients have the potential to influence genetic differentiation among populations ultimately leading to allopatric speciation. However, environmental gradients can also facilitate hybridization between closely related taxa. We investigated a putative hybrid zone in western Ecuador, involving two polytypic wren species (Aves: Troglodytidae), Campylorhynchus zonatus and C. fasciatus. Our study addressed two primary questions: (1) Is there evidence of population structure and genetic admixture between these taxa in western Ecuador? and (2) What are the relative contributions of isolation by distance and isolation by the environment to the observed genetic differentiation along the environmental gradient in this region? We analyzed 4409 single-nucleotide polymorphisms (SNPs) from 112 blood samples sequenced using ddRadSeq and a de novo assembly. The optimum number of genetic clusters ranged from 2 to 4, aligning with geographic origins, known phylogenetics, and physical or ecological constraints. We observed notable transitions in admixture proportions along the environmental gradient in western Ecuador between C. z. brevirostris and the northern and southern genetic clusters of C. f. pallescens. Genetic differentiation between the two C. f. pallescens populations could be attributed to an unreported potential physical barrier in central western Ecuador, where the proximity of the Andes to the coastline restricts lowland habitats, limiting dispersal and gene flow, especially among dry-habitat specialists. The observed admixture in C. f. pallescens suggests that this subspecies may be a hybrid between C. z. brevirostris and C. fasciatus, with varying degrees of admixture in western Ecuador and northwestern Peru. We found evidence of isolation by distance, while isolation by the environment was less pronounced but still significant for annual mean precipitation and precipitation seasonality. This study enhances our understanding of avian population genomics in tropical regions.
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What is natural behavior and how does it differ from laboratory-based behavior? The "natural" in natural behavior implies the everyday, complex, ever-changing, yet predictable environment in which children grow up. "Behavior" is motor action and is foundational to psychology, as it includes all things to function in everyday environments. Is behavior demonstrated in the laboratory un-natural? Suppose behavior emerges spontaneously, in a context that is most common to the animal but an observer is there to document it using particular research tools. Is that behavior natural or natural-ish? Methods can powerfully affect conclusions about infant experiences and learning. In the lab, tasks are typically narrowly constrained where infants and children have little opportunity to display the variety of behaviors in their repertoire. Data from naturalistic observations may paint a very different picture of learning and development from those based on structured tasks, exposing striking variability in the environment and behavior and new relations between the organism and its environment. Using motor development as a model system, in this chapter we compare frameworks, methods, and findings originating in the lab and in the field, applied and adapted in different settings. Specifically, we recount our journey of pursuing the study of cultural influences on motor development in Tajikistan, and the challenges, surprises, and lessons learned.
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Desenvolvimento Infantil , Humanos , Lactente , Desenvolvimento Infantil/fisiologia , Comportamento do Lactente , Meio Social , Cultura , Destreza Motora/fisiologia , AprendizagemRESUMO
BACKGROUND: There is persistent controversy surrounding the merit of surgical volume benchmarks being used solely as a sufficient proxy for assessing the quality of open abdominal aortic aneurysm (AAA) repair. Importantly, operative volume quotas may fail to reflect a more nuanced and comprehensive depiction of surgical outcomes most relevant to patients. Accordingly, we herein propose a patient-centered textbook outcome (TO) for AAA repair that is analogous to other large magnitude extirpative operations performed in other surgical specialties, and test its feasibility to discriminate hospital performance using Society for Vascular Surgery (SVS) volume guidelines. METHODS: All elective open infrarenal AAA repairs (OAR) in the SVS-Vascular Quality Initiative were examined (2009-2022). The primary end point was a TO, defined as a composite of no in-hospital complication or reintervention/reoperation, length of stay of ≤10 days, home discharge, and 1-year survival rates. The discriminatory ability of the TO measure was assessed by comparing centers that did or did not meet the SVS annual OAR volume threshold recommendation (high volume ≥10 OARs/year; low volume <10 OARs/year). Logistic regression and multivariable models adjusted for patient and procedure-related differences. RESULTS: A total of 9657 OARs across 198 centers were analyzed (mean age, 69.5 ± 8.4 years; female, 26%; non-White, 12%). A TO was identified in 44% (n = 4293) of the overall cohort. The incidence of individual TO components included no in-hospital complication (61%), no in-hospital reintervention or reoperation (92%), length of stay of ≤10 days (78%), home discharge (76%), and 1-year survival (91%). Median annual center volume was 6 (interquartile range, 3-10) and a majority of centers did not meet the SVS volume suggested threshold (<10 OARs/year, n = 148 [74%]). However, most patients (6265 of 9657 [65%]) underwent OAR in high-volume hospitals. When comparing high- and low-volume centers, a TO was more likely to occur in high-volume institutions: ≥10 OARs/year (46%) vs <10 OARs/year (42%; P = .0006). The association of a protective effect for higher center volume remained after risk adjustment (odds ratio, 1.1; 95% confidence interval, 1.05-1.26; P = .003). CONCLUSIONS: TOs for elective OAR reflect a more nuanced and comprehensive patient centered proxy to measure care delivery, consistent with other surgical specialties. Surprisingly, a TO was achieved in <50% of elective AAA cases nationally. Although the likelihood of a TO seems to correlate with SVS center volume recommendations, it more importantly reflects elements which may be prioritized by patients and thus offers insights into further improving real-world AAA care.
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Short-term protein-calorie dietary restriction (StDR) is a promising preoperative strategy for modulating postoperative inflammation. We have previously shown marked gut microbial activity during StDR, but relationships between StDR, the gut microbiome, and systemic immunity remain poorly understood. Mucosal-associated invariant T-cells (MAITs) are enriched on mucosal surfaces and in circulation, bridge innate and adaptive immunity, are sensitive to gut microbial changes, and may mediate systemic responses to StDR. Herein, we characterized the MAIT transcriptomic response to StDR using single-cell RNA sequencing of human PBMCs and evaluated gut microbial species-level changes through sequencing of stool samples. Healthy volunteers underwent 4 days of DR during which blood and stool samples were collected before, during, and after DR. MAITs composed 2.4% of PBMCs. More MAIT genes were differentially downregulated during DR, particularly genes associated with MAIT activation (CD69), regulation of pro-inflammatory signaling (IL1, IL6, IL10, TNFα), and T-cell co-stimulation (CD40/CD40L, CD28), whereas genes associated with anti-inflammatory IL10 signaling were upregulated. Stool analysis showed a decreased abundance of multiple MAIT-stimulating Bacteroides species during DR. The analyses suggest that StDR potentiates an anti-inflammatory MAIT immunophenotype through modulation of TCR-dependent signaling, potentially secondary to gut microbial species-level changes.
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Restrição Calórica , Microbioma Gastrointestinal , Células T Invariantes Associadas à Mucosa , Humanos , Células T Invariantes Associadas à Mucosa/imunologia , Masculino , Adulto , Feminino , Fezes/microbiologia , Inflamação/imunologia , Adulto Jovem , Voluntários Saudáveis , TranscriptomaRESUMO
Visual mimicry is less understood in birds than in other taxa. The interspecific social dominance mimicry (ISDM) hypothesis asserts that subordinate species resemble dominant ones to reduce aggression. Plumage mimicry has also been consistently noted in mixed-species flocks (MSFs), suggesting a connection to grouping behaviour, although it is unclear whether this is linked to ISDM. We studied greater necklaced laughingthrush (GNLT, Pterorhinus pectoralis) and lesser necklaced laughingthrush (LNLT, Garrulax monileger), which were recently placed in different genera. Measurements of 162 museum specimens showed LNLT converging in sympatry with GNLT in necklace colour, but diverging in necklace to body ratio, with proportionally smaller necklaces. The species were closely associated in six of seven MSF systems from Nepal to China. In a study of foraging behaviour in Nepal, aggression was rare between the species, LNLT followed GNLT and had lower foraging rates when further from GNLT. Our data suggest a link between this MSF-associated mimicry and ISDM, and that the subordinate LNLT may be the mimic and gain more from the resemblance. The species spend much time together in dense and poorly lit vegetation, where the LNLTs resemblance to GNLTs potentially allows them to forage closer to GNLTs than would be otherwise possible.
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Participants in mixed-species bird flocks (MSFs) have been shown to associate with species that are similar in body size, diet, and evolutionary history, suggesting that facilitation structures these assemblages. In addition, several studies have suggested that species in MSFs resemble each other in their plumage, but this question has not been systematically investigated for any MSF system. During the nonbreeding season of 2020 and 2021, we sampled 585 MSFs on 14 transects in 2 habitats of Tongbiguang Nature Reserve in western Yunnan Province, China. We performed social network analysis and the Multiple Regression Quadratic Assignment Procedure to evaluate the effect of 4 species traits (body size, overall plumage color, distinctive plumage patterns, and diet) and evolutionary history on species association strength at the whole-MSF and within-MSF levels. All 41 significant relationships showed that species with stronger associations were more similar in their various traits. Body size had the strongest effect on association strength, followed by phylogeny, plumage patterns, and plumage color; diet had the weakest effect. Our results are consistent with the hypotheses that the benefits of associating with phenotypically similar species outweigh the potential costs of interspecific competition, and that trait matching can occur in plumage characteristics, albeit more weakly than in other traits. Several explanations exist as to why similarities in plumage may occur in MSFs, including that they could reduce predators' ability to target phenotypically "odd" individuals. Whether trait matching in plumage occurs through assortative processes in ecological time or is influenced by co-evolution requires further study.
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Migrating species are particularly vulnerable to habitat loss. A new study shows that migrating birds use seasonally different stopover hotspots, which need to be protected better.
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Migração Animal , Aves , Animais , Estações do Ano , Ecossistema , Conservação dos Recursos NaturaisRESUMO
BACKGROUND: Insurance companies have adopted variable and inconsistent approval criteria for chronic venous disease (CVD) treatment. Although vein ablation (VA) is accepted as the standard of care for venous ulcers, the treatment criteria for patients with milder forms of CVD remain controversial. This study aims to identify factors associated with a lack of clinical improvement (LCI) in patients with less severe CVD without ulceration undergoing VA to improve patient selection for treatment. METHODS: We performed a retrospective analysis of patients undergoing VA for CEAP C2 to C4 disease in the Vascular Quality Initiative varicose veins database from 2014 to 2023. Patients who required intervention in multiple veins, had undergone prior interventions, or presented with CEAP C5 to C6 disease were excluded. The difference (Δ) in venous clinical severity score (VCSS; VCSS before minus after the procedure) was used to categorize the patients. Patients with a ΔVCSS of ≤0 were defined as having LCI after VA, and patients with ≥1 point decrease in the VCSS after VA (ΔVCSS ≥1) as having some benefit from the procedure and, therefore, "clinical improvement." The characteristics of both groups were compared, and multivariable regression analysis was performed to identify factors independently associated with LCI. A second analysis was performed based on the VVSymQ instrument, which measures patient-reported outcomes using five specific symptoms (ie, heaviness, achiness, swelling, throbbing pain, and itching). Patients with LCI showed no improvement in any of the five symptoms, and those with clinical improvement had a decrease in severity of at least one symptom. RESULTS: A total of 3544 patients underwent initial treatment of CVD with a single VA. Of the 3544 patients, 2607 had VCSSs available before and after VA, and 420 (16.1%) had LCI based on the ΔVCSS. Patients with LCI were more likely to be significantly older and African American and have CEAP C2 disease compared with patients with clinical improvement. Patients with clinical improvement were more likely to have reported using compression stockings before treatment. The vein diameters were not different between the two groups. The incidence of complications was overall low, with minor differences between the two groups. However, the patients with LCI were significantly more likely to have symptoms after intervention than those with improvement. Patients with LCI were more likely to have technical failure, defined as vein recanalization. On multivariable regression, age (odds ratio [OR], 1.01; 95% confidence interval [CI], 1.00-1.02) and obesity (OR, 1.47; 95% CI, 1.09-2.00) were independently associated with LCI, as was treatment of less severe disease (CEAP C2; OR, 1.82; 95% CI, 1.30-2.56) compared with more advanced disease (C4). The lack of compression therapy before intervention was also associated with LCI (OR, 6.05; 95% CI, 4.30-8.56). The analysis based on the VVSymQ showed similar results. CONCLUSIONS: LCI after VA is associated with treating patients with a lower CEAP class (C2 vs C4) and a lack of compression therapy before intervention. Importantly, no significant association between vein size and clinical improvement was observed.