Magnetic structures in R5Pt2In4 (R = Tb-Tm) investigated by neutron powder diffraction.

Results of the neutron powder diffraction measurements carried out for R5Pt2In4 (R = Tb-Tm) are reported. The compounds crystallize in an orthorhombic crystal structure of the Lu5Ni2In4-type with the rare earth atoms occupying three different sublattices. At low temperatures the rare earth magnetic moments order below the critical temperature equal to 105, 93, 28, 12 and 3.8 K for R = Tb, Dy, Ho, Er and Tm, respectively. With decreasing temperature the rare earth magnetic moments at the 2a and 4g2 sites order first, while the moments at the 4g1 site order at lower temperatures. Ferrimagnetic order along the c axis, described by the propagation vector k1 = [0, 0, 0], develops in Tb5Pt2In4 below the Curie temperature (TC = 108 K). At lower temperatures, an antiferromagnetic component in the ab plane appears. The component is incommensurate with the crystal structure (k2 = [0, 0.66, ½]), but it turns into a commensurate one (k3 = [0, 0, ½]) with decreasing temperature. Antiferromagnetic order along the c axis, described by k4 = [½, 0, 0], is found in Dy5Pt2In4 below the Néel temperature (TN = 93 K). The k4-related component disappears below 80 K and the magnetic structure transforms into a ferro/ferrimagnetic one described by k1 = [0, 0, 0]. Further decrease in temperature leads to the appearance of an incommensurate antiferromagnetic component along the ab plane below 10 K (k2 = [0, 0.45, ½]), which finally turns into a commensurate one (k5 = [0, ½, ½]). In Ho5Pt2In4, a sine-modulated magnetic structure with moments parallel to the c axis (k6 = [⅓,0,0]) is observed below 28 K. With a decrease in temperature, new components, related to k1 = [0, 0, 0] (bc plane) and k4 = [½, 0, 0] (c axis), appear. The coexistence of two orderings - in the ab plane (k1 = [0, 0, 0]) and a modulated one with moments along the b axis (k7 = [kx, 0, 0]) - is found in Er5Pt2In4 below 12 K. Decreasing temperature leads to the order-order transformation of the k1-related component to another one with magnetic moments still constrained to the ab plane and preserved value of the propagation vector (i.e. k1 = [0, 0, 0]). Tm5Pt2In4 orders antiferromagnetically below TN = 4.1 K. Thulium magnetic moments lie in the ab plane, while the magnetic structure is described by k5 = [0, ½ , ½]. The direction of magnetic moments depends on the rare earth element involved and indicates an influence of single ion anisotropy resulting from interaction with the crystalline electric field.

Multigenerational Fitness Effects of Natural Immigration Indicate Strong Heterosis and Epistatic Breakdown in a Wild Bird Population.

AbstractThe fitness of immigrants and their descendants produced within recipient populations fundamentally underpins the genetic and population dynamic consequences of immigration. Immigrants can in principle induce contrasting genetic effects on fitness across generations, reflecting multifaceted additive, dominance, and epistatic effects. Yet full multigenerational and sex-specific fitness effects of regular immigration have not been quantified within naturally structured systems, precluding inference on underlying genetic architectures and population outcomes. We used four decades of song sparrow (Melospiza melodia) life history and pedigree data to quantify fitness of natural immigrants, natives, and their F1, F2, and backcross descendants and test for evidence of nonadditive genetic effects. Values of key fitness components (including adult lifetime reproductive success and zygote survival) of F1 offspring of immigrant-native matings substantially exceeded their parent mean, indicating strong heterosis. Meanwhile, F2 offspring of F1-F1 matings had notably low values, indicating surprisingly strong epistatic breakdown. Furthermore, magnitudes of effects varied among fitness components and differed between female and male descendants. These results demonstrate that strong nonadditive genetic effects on fitness can arise within weakly structured and fragmented populations experiencing frequent natural immigration. Such effects will substantially affect the net degree of effective gene flow and resulting local genetic introgression and adaptation.

Multi-generation genetic contributions of immigrants reveal cryptic elevated and sex-biased effective gene flow within a natural meta-population.

Impacts of immigration on micro-evolution and population dynamics fundamentally depend on net rates and forms of resulting gene flow into recipient populations. Yet, the degrees to which observed rates and sex ratios of physical immigration translate into multi-generational genetic legacies have not been explicitly quantified in natural meta-populations, precluding inference on how movements translate into effective gene flow and eco-evolutionary outcomes. Our analyses of three decades of complete song sparrow (Melospiza melodia) pedigree data show that multi-generational genetic contributions from regular natural immigrants substantially exceeded those from contemporary natives, consistent with heterosis-enhanced introgression. However, while contributions from female immigrants exceeded those from female natives by up to three-fold, male immigrants' lineages typically went locally extinct soon after arriving. Both the overall magnitude, and the degree of female bias, of effective gene flow therefore greatly exceeded those which would be inferred from observed physical arrivals, altering multiple eco-evolutionary implications of immigration.

Angina en pacientes con estenosis aórtica grave sometidos a implante percutáneo de la válvula aórtica / Angina in patients with severe aortic stenosis undergoing transcatheter aortic valve replacement

Introducción y objetivos: Evaluar la prevalencia, las características clínicas y el impacto de la angina en pacientes con estenosis aórtica sometidos a implante percutáneo de válvula aórtica (TAVI). Métodos: Se analizó a 1.687 pacientes consecutivos con estenosis aórtica sometidos a TAVI, clasificados en función de la presencia o ausencia basal de angina. Los datos basales, del procedimiento y del seguimiento se recogieron en una base de datos local. Resultados: Un total de 497 pacientes (29%) presentaban angina antes del TAVI. Los pacientes con angina basal presentaban peor clase funcional (NYHA> II, el 69% frente al 63%; p=0,017) y una mayor prevalencia de enfermedad coronaria (el 74% frente al 56%; p <0,001). La angina basal no mostró impacto pronóstico a 1 año en mortalidad por cualquier causa (HR=1,02; IC95%, 0,71-1,48; p=0,898) ni en mortalidad cardiovascular (HR=1,2; IC95%, 0,69-2,11; p=0,517). Sin embargo, la persistencia de angina 30 días después del procedimiento se asoció con un incremento en la mortalidad a 1 año, tanto total (HR=4,86; IC95%, 1,71-13,8; p=0,003) como de causa cardiovascular (HR=20,7; IC95%, 3,50-122,6; p=0,001). Conclusiones: Más de un cuarto de los pacientes con estenosis aórtica sometidos a TAVI tenían angina antes del procedimiento. La angina basal no mostró impacto pronóstico alguno. Sin embargo, la persistencia de angina 30 días después del procedimiento se asoció con una mayor mortalidad al año.(AU)

Introduction and objectives: To evaluate the prevalence, clinical characteristics, and outcomes of patients with angina undergoing transcatheter aortic valve replacement (TAVR) for severe aortic stenosis. Methods: A total of 1687 consecutive patients with severe aortic stenosis undergoing TAVR at our center were included and classified according to patient-reported angina symptoms prior to the TAVR procedure. Baseline, procedural and follow-up data were collected in a dedicated database. Results: A total of 497 patients (29%) had angina prior to the TAVR procedure. Patients with angina at baseline showed a worse New York Heart Association (NYHA) functional class (NYHA class> II: 69% vs 63%; P=.017), a higher rate of coronary artery disease (74% vs 56%; P <.001), and a lower rate of complete revascularization (70% vs 79%; P <.001). Angina at baseline had no impact on all-cause mortality (HR, 1.02; 95%CI, 0.71-1.48; P=.898) and cardiovascular mortality (HR, 1.2; 95%CI, 0.69-2.11; P=.517) at 1 year. However, persistent angina at 30 days post-TAVR was associated with increased all-cause mortality (HR, 4.86; 95%CI, 1.71-13.8; P=.003) and cardiovascular mortality (HR, 20.7; 95%CI, 3.50-122.6; P=.001) at 1-year follow-up. Conclusions: More than one-fourth of patients with severe aortic stenosis undergoing TAVR had angina prior to the procedure. Angina at baseline did not appear to be a sign of a more advanced valvular disease and had no prognostic impact; however, persistent angina at 30 days post-TAVR was associated with worse clinical outcomes.(AU)

High-Speed On-Site Deep Learning-Based FFR-CT Algorithm: Evaluation Using Invasive Angiography as the Reference Standard.

BACKGROUND. Estimation of fractional flow reserve from coronary CTA (FFR-CT) is an established method of assessing the hemodynamic significance of coronary lesions. However, clinical implementation has progressed slowly, partly because of off-site data transfer with long turnaround times for results. OBJECTIVE. The purpose of this study was to evaluate the diagnostic performance of FFR-CT computed on-site with a high-speed deep learning-based algorithm with invasive hemodynamic indexes as the reference standard. METHODS. This retrospective study included 59 patients (46 men, 13 women; mean age, 66.5 ± 10.2 years) who underwent coronary CTA (including calcium scoring) followed within 90 days by invasive angiography with invasive fractional flow reserve (FFR) and/or instantaneous wave-free ratio measurements from December 2014 to October 2021. Coronary artery lesions were considered to have hemodynamically significant stenosis in the presence of invasive FFR of 0.80 or less and/or instantaneous wave-free ratio of 0.89 or less. A single cardiologist evaluated the CTA images using an on-site deep learning-based semiautomated algorithm entailing a 3D computational flow dynamics model to determine FFR-CT for coronary artery lesions detected with invasive angiography. Time for FFR-CT analysis was recorded. FFR-CT analysis was repeated by the same cardiologist in 26 randomly selected examinations and by a different cardiologist in 45 randomly selected examinations. Diagnostic performance and agreement were assessed. RESULTS. A total of 74 lesions were identified with invasive angiography. FFR-CT and invasive FFR had strong correlation (r = 0.81) and, in Bland-Altman analysis, bias of 0.01 and 95% limits of agreement of -0.13 to 0.15. FFR-CT had AUC for hemodynamically significant stenosis of 0.975. At a cutoff of 0.80 or less, FFR-CT had 95.9% accuracy, 93.5% sensitivity, and 97.7% specificity. In 39 lesions with severe calcifications (≥ 400 Agatston units), FFR-CT had AUC of 0.991 and at a cutoff of 0.80, 94.7% sensitivity, 95.0% specificity, and 94.9% accuracy. Mean analysis time per patient was 7 minutes 54 seconds. Intraobserver agreement (intraclass correlation coefficient, 0.85; bias, -0.01; 95% limits of agreement, -0.12 and 0.10) and interobserver agreement (intraclass correlation coefficient, 0.94; bias, -0.01; 95% limits of agreement, -0.08 and 0.07) were good to excellent. CONCLUSION. A high-speed on-site deep learning-based FFR-CT algorithm had excellent diagnostic performance for hemodynamically significant stenosis with high reproducibility. CLINICAL IMPACT. The algorithm should facilitate implementation of FFR-CT technology into routine clinical practice.

Angina in patients with severe aortic stenosis undergoing transcatheter aortic valve replacement.

INTRODUCTION AND OBJECTIVES: To evaluate the prevalence, clinical characteristics, and outcomes of patients with angina undergoing transcatheter aortic valve replacement (TAVR) for severe aortic stenosis. METHODS: A total of 1687 consecutive patients with severe aortic stenosis undergoing TAVR at our center were included and classified according to patient-reported angina symptoms prior to the TAVR procedure. Baseline, procedural and follow-up data were collected in a dedicated database. RESULTS: A total of 497 patients (29%) had angina prior to the TAVR procedure. Patients with angina at baseline showed a worse New York Heart Association (NYHA) functional class (NYHA class> II: 69% vs 63%; P=.017), a higher rate of coronary artery disease (74% vs 56%; P <.001), and a lower rate of complete revascularization (70% vs 79%; P <.001). Angina at baseline had no impact on all-cause mortality (HR, 1.02; 95%CI, 0.71-1.48; P=.898) and cardiovascular mortality (HR, 1.2; 95%CI, 0.69-2.11; P=.517) at 1 year. However, persistent angina at 30 days post-TAVR was associated with increased all-cause mortality (HR, 4.86; 95%CI, 1.71-13.8; P=.003) and cardiovascular mortality (HR, 20.7; 95%CI, 3.50-122.6; P=.001) at 1-year follow-up. CONCLUSIONS: More than one-fourth of patients with severe aortic stenosis undergoing TAVR had angina prior to the procedure. Angina at baseline did not appear to be a sign of a more advanced valvular disease and had no prognostic impact; however, persistent angina at 30 days post-TAVR was associated with worse clinical outcomes.

Large-scale oxygen order phase transitions and fast ordering kinetics at moderate temperatures in Nd2NiO4+δ electrodes.

Non-stoichiometric 214-nickelates with Ruddlesden-Popper (RP) type frameworks emerged as potential candidates for mixed electronic/ionic conductors in the intermediate temperature range. In this work we investigated structural aspects of the oxygen ion mobility diffusion mechanisms in non-stoichiometric Nd2NiO4+δ nickelates by X-ray (laboratory and synchrotron) as well by neutron diffraction. Temperature dependent synchrotron powder diffraction revealed a phase diagram of unprecedented complexity, involving a series of highly organized, 3D modulated phases related to oxygen ordering below 800 K. All phase transitionsimply translational periodicities exceeding 100 Å, and are found to be of 1st order, together with fast ordering kinetics. These surprising structural correlations, induced by the presence of interstitial oxygen atoms, suggest a collective phason-like oxygen diffusion mechanism together with dynamical contributions from the aperiodical lattice creating shallow diffusion pathways down to room temperature.

Syncope in Patients With Severe Aortic Stenosis Undergoing Transcatheter Aortic Valve Replacement.

BACKGROUND: No data exist on the clinical and prognostic significance of syncope in patients undergoing transcatheter aortic valve replacement (TAVR) for severe aortic stenosis. METHODS: A total of 1705 consecutive patients with severe aortic stenosis undergoing TAVR in a tertiary university centre between 2007 and 2021 were included and classified according to the presence of syncope before the TAVR procedure. Baseline, procedural, and follow-up data were collected prospectively in a dedicated database. RESULTS: A total of 115 patients (7%) presented with syncope before the TAVR procedure. Of these, 15 patients (13%) showed arrhythmic episodes as the probable cause of the syncope, and all of them had pacemakers implanted at a median of 13 (6 to 53) days before the TAVR procedure. Patients with syncope were older (82 ± 8 years vs 80 ± 8 years, P = 0.001) and had a higher rate of pacemaker implantation before the TAVR procedure (27% vs 14%, P < 0.001), with no differences between groups regarding the severity of aortic stenosis (transvalvular gradient, valve area). There were no differences between groups in 30-day (adjusted hazard ratio [HR], 1.28; 95% confidence interval [CI], 0.46-3.60) and 1-year (adjusted HR, 0.71; 95% CI, 0.0.35-1.45) mortality following TAVR. CONCLUSIONS: Syncope was not associated with a more advanced valvular disease and had no significant prognostic impact on patients undergoing TAVR. However, arrhythmias and conduction-system disturbances were more common in patients with previous syncope and might play a relevant role in the pathogenesis of syncope in patients with aortic stenosis.

Continued non-vitamin K antagonist oral anticoagulants versus vitamin K antagonists during transcatheter aortic valve implantation.

BACKGROUND: One-third of patients undergoing transcatheter aortic valve implantation (TAVI) have an indication for long-term oral anticoagulation (OAC). AIMS: We aimed to investigate whether continued non-vitamin K antagonist oral anticoagulant (NOAC) therapy compared with continued vitamin K antagonist (VKA) therapy during TAVI is equally safe and effective.  Methods: Consecutive patients on OAC with either NOAC or VKA undergoing transfemoral TAVI at five European centres were enrolled. The primary outcome measure was a composite of major/life-threatening bleeding, stroke, and all-cause mortality at 30 days. RESULTS: In total, 584 patients underwent TAVI under continued OAC with 294 (50.3%) patients receiving VKA and 290 (49.7%) patients receiving NOAC. At 30 days, the composite primary outcome had occurred in 51 (17.3%) versus 36 (12.4%) patients with continued VKA and with continued NOAC, respectively (odds ratio [OR] 0.68, 95% confidence interval [CI]: 0.43-1.07; p=0.092). Rates of major/life-threatening bleeding (OR 0.87, 95% CI: 0.52-1.47; p=0.606) and stroke (OR 1.02, 95% CI: 0.29-3.59; p=0.974) were not different between groups. In a multivariate Cox regression analysis, continued NOAC, compared with continued VKA, was associated with a lower risk for all-cause 1-year mortality (hazard ratio [HR] 0.61, 95% CI: 0.37-0.98; p=0.043). The analysis of the propensity score-matched cohort revealed similar results. CONCLUSIONS: Continued NOAC compared with continued VKA during TAVI led to comparable outcomes with regard to the composite outcome measure indicating that continued OAC with both drugs is feasible. These hypothesis-generating results need to be confirmed by a dedicated randomised controlled trial.

Association of N-terminal pro-B-type natriuretic peptide with mortality in elderly (≥80 years) patients undergoing percutaneous coronary intervention.

OBJECTIVES: The aim of this study was to determine the role of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in the prognostication of patients ≥80 years of age undergoing percutaneous coronary intervention (PCI). BACKGROUND: Elderly patients with coronary artery disease in need of PCI represent a growing patient population. Advanced risk prediction in this frail and comorbid patient population is important. METHODS: A total of 460 consecutive patients ≥80 years of age undergoing PCI for acute (ACS) or chronic coronary syndromes (CCS) at the University Hospital Zurich, Switzerland, between January 2016 and December 2018 and with available baseline NT-proBNP levels were included in the analysis. Patients were stratified according to baseline NT-proBNP levels. The primary endpoint was all-cause mortality at a median follow-up of 33 (interquartile range: 3-392) days. RESULTS: Median baseline NT-proBNP levels were 1411 (457-3984) ng/L. All-cause mortality was 7.8% in the lowest and 27.8% in the highest NT-proBNP quartile group (p < 0.001). In patients with ACS, all-cause mortality was 4.8% and 30.4% in the lowest and the highest NT-proBNP quartile (p < 0.001), and corresponding rates in patients with CCS were 11.1% and 22.2% (p = 0.38). In multivariable Cox regression analysis, baseline NT-proBNP levels were independently associated with an increased risk of all-cause mortality (adjusted hazard ratio: 1.00, 95% confidence interval: 1.00-1.00, p = 0.04). CONCLUSIONS: Baseline NT-proBNP levels were identified as independent predictor of mortality in elderly (≥80 years) patients undergoing PCI. Hence, baseline NT-proBNP allows for the identification of a high-risk elderly patient subset.

Percutaneous Coronary Intervention Pre-TAVR: Current State of the Evidence.

PURPOSE OF REVIEW: This review intends to give an up-to-date overview of the current state of evidence in the treatment of coronary artery disease (CAD) in patients undergoing transcatheter aortic valve replacement (TAVR), focusing on percutaneous coronary interventions (PCI) pre-TAVR. RECENT FINDINGS: The recently published ACTIVATION trial is the 1st randomized trial comparing coronary revascularization (PCI) versus medical treatment in patients with significant CAD undergoing TAVR. With the caveat of several major limitations of the trial, the results of this study raised the question about the appropriateness of the common practice to routinely revascularize coronary stenosis before TAVR. Aortic valve stenosis is the most common valvular heart disease among the elderly and it often co-occurs with CAD. TAVR is increasingly considered an alternative to surgical aortic valve replacement not only in the elderly population but also in younger and lower-risk patients. The impact of co-existing CAD on clinical outcomes as well as the optimal timing of PCI in TAVR candidates is still unclear and the subject of ongoing randomized trials. Meanwhile, it is common practice in many centers to routinely perform invasive coronary angiography and PCI for significant coronary disease as part of the TAVR workup. While computed tomography angiography has emerged as a possible alternative to the invasive coronary angiography in patients with low pre-test probability for CAD, the value of functional invasive assessment of coronary lesions in the pre-TAVR setting has still to be clarified. Also, there is an increasing interest in the clinical relevance and optimal management of the potentially challenging coronary access post-TAVR, requiring further research.

Genetic variance in fitness indicates rapid contemporary adaptive evolution in wild animals.

The rate of adaptive evolution, the contribution of selection to genetic changes that increase mean fitness, is determined by the additive genetic variance in individual relative fitness. To date, there are few robust estimates of this parameter for natural populations, and it is therefore unclear whether adaptive evolution can play a meaningful role in short-term population dynamics. We developed and applied quantitative genetic methods to long-term datasets from 19 wild bird and mammal populations and found that, while estimates vary between populations, additive genetic variance in relative fitness is often substantial and, on average, twice that of previous estimates. We show that these rates of contemporary adaptive evolution can affect population dynamics and hence that natural selection has the potential to partly mitigate effects of current environmental change.

Revisiting the antiferromagnetic structure of Tb14Ag51: the importance of distinguishing alternative symmetries for a multidimensional order parameter.

The antiferromagnetic structure of Tb14Ag51 with the propagation vector [1/3, 1/3, 0] and the parent space group P6/m is revisited using both magnetic symmetry and irreducible representation arguments. A new magnetic structure under the hexagonal Shubnikov magnetic space group P6' which fits much better the experimental data is found. This new solution was obtained by constraining the spin arrangement to one of the three possible magnetic space groups of maximal symmetry that can be realized by a magnetic ordering transforming according to the four-dimensional physically irreducible representation that is known to be relevant in this magnetic phase. The refined model, parameterized under P6', implicitly includes the presence of a third harmonic with the propagation vector at the gamma point [0, 0, 0], which has an important weight in the final result. The structure consists of 13 symmetry-independent Tb magnetic moments with the same size of 8.48 (2) µB, propagating cycloidally in the ab plane. The modulation has a substantial deviation from being purely sinusoidal due to the contribution of the mentioned third harmonic.

Depressive symptoms in patients after primary and secondary prophylactic ICD implantation.

OBJECTIVE: Implantable cardioverter defibrillators (ICD) are successfully used to treat life-threatening arrhythmias and prevent sudden cardiac death. However, they are also known to have a major psychological impact leading to higher prevalence of depression and anxiety in a substantial proportion of patients. The aim of this study was to assess the prevalence of depressive symptoms in a large cohort of ICD carriers with a different clinical background and to compare prevalence and risk factors between patients with primary and secondary prophylactic indication for ICD implantation. METHODS: 315 out of 622 patients (50.6%), who regularly attended ICD assessments at the University Hospital Zurich completed the Beck Depression Inventory (BDI I-II) to estimate current depressive symptoms. RESULTS: Overall, depressive symptoms were common in ICD patients, with 20.3% of the patients showing clinically relevant depression (12.4% mild depressive symptoms, 6.0% moderate, 1.9% severe). Moderate to severe depressive symptoms seem to be more likely in patients with secondary prophylactic indication of the ICD as compared to a group of patients with primary prophylactic implantation. Patients that received more than 5 ICD shocks since implantation reveal more depressive symptoms than those with less events. Mean BDI Score in total (n = 315) was at 8.44 ± 7.56 without a statistically significant difference between the primary (M = 8.04 ± 7.10, n = 153) and secondary (M = 8.81 ± 7.98, n = 162) preventive group (p value = 0.362), even after adjustment for various clinical characteristics. ICD patients should therefore be well supported and advised concerning the psychological impact of their device and particular aspects of daily life concerns (e.g. physical activity), with a special focus on patients, who have received multiple shocks.

Are immigrants outbred and unrelated? Testing standard assumptions in a wild metapopulation.

Immigration into small recipient populations is expected to alleviate inbreeding and increase genetic variation, and hence facilitate population persistence through genetic and/or evolutionary rescue. Such expectations depend on three standard assumptions: that immigrants are outbred, unrelated to existing natives at arrival, and unrelated to each other. These assumptions are rarely explicitly verified, including in key field systems in evolutionary ecology. Yet, they could be violated due to non-random or repeated immigration from adjacent small populations. We combined molecular genetic marker data for 150-160 microsatellite loci with comprehensive pedigree data to test the three assumptions for a song sparrow (Melospiza melodia) population that is a model system for quantifying effects of inbreeding and immigration in the wild. Immigrants were less homozygous than existing natives on average, with mean homozygosity that closely resembled outbred natives. Immigrants can therefore be considered outbred on the focal population scale. Comparisons of homozygosity of real or hypothetical offspring of immigrant-native, native-native and immigrant-immigrant pairings implied that immigrants were typically unrelated to existing natives and to each other. Indeed, immigrants' offspring would be even less homozygous than outbred individuals on the focal population scale. The three standard assumptions of population genetic and evolutionary theory were consequently largely validated. Yet, our analyses revealed some deviations that should be accounted for in future analyses of heterosis and inbreeding depression, implying that the three assumptions should be verified in other systems to probe patterns of non-random or repeated dispersal and facilitate precise and unbiased estimation of key evolutionary parameters.

Immigration counter-acts local micro-evolution of a major fitness component: Migration-selection balance in free-living song sparrows.

Ongoing adaptive evolution, and resulting "evolutionary rescue" of declining populations, requires additive genetic variation in fitness. Such variation can be increased by gene flow resulting from immigration, potentially facilitating evolution. But, gene flow could in fact constrain rather than facilitate local adaptive evolution if immigrants have low additive genetic values for local fitness. Local migration-selection balance and micro-evolutionary stasis could then result. However, key quantitative genetic effects of natural immigration, comprising the degrees to which gene flow increases the total local additive genetic variance yet counteracts local adaptive evolutionary change, have not been explicitly quantified in wild populations. Key implications of gene flow for population and evolutionary dynamics consequently remain unclear. Our quantitative genetic analyses of long-term data from free-living song sparrows (Melospiza melodia) show that mean breeding value for local juvenile survival to adulthood, a major component of fitness, increased across cohorts more than expected solely due to drift. Such micro-evolutionary change should be expected given nonzero additive genetic variance and consistent directional selection. However, this evolutionary increase was counteracted by negative additive genetic effects of recent immigrants, which increased total additive genetic variance but prevented a net directional evolutionary increase in total additive genetic value. These analyses imply an approximate quantitative genetic migration-selection balance in a major fitness component, and hence demonstrate a key mechanism by which substantial additive genetic variation can be maintained yet decoupled from local adaptive evolutionary change.

Safety and Efficacy of Transcatheter Aortic Valve Replacement With Continuation of Vitamin K Antagonists or Direct Oral Anticoagulants.

OBJECTIVES: This study investigated whether transcatheter aortic valve replacement (TAVR) with peri-procedural continuation of oral anticoagulation is equally safe and efficacious as TAVR with peri-procedural interruption of anticoagulation. BACKGROUND: A significant proportion of patients undergoing TAVR have an indication for long-term oral anticoagulation. The optimal peri-procedural management of such patients is unknown. METHODS: Consecutive patients on oral anticoagulation who underwent transfemoral TAVR at 5 European centers were enrolled. Oral anticoagulation was either stopped 2 to 4 days before TAVR or continued throughout the procedure. Primary safety outcome was major bleeding. Secondary efficacy endpoints included vascular complications, stroke, and mortality. RESULTS: Of 4,459 patients, 584 patients were treated with continuation of anticoagulation and 733 with interruption of anticoagulation. At 30 days, major or life-threatening bleedings occurred in 66 (11.3%) versus 105 (14.3%; odds ratio [OR]: 0.86; 95% confidence interval [CI]: 0.61 to 1.21; p = 0.39) and major vascular complications in 64 (11.0%) versus 90 (12.3%; OR: 0.89; CI: 0.62 to 1.27; p = 0.52) of patients with continuation and with interruption of anticoagulation, respectively. Transfusion of packed red blood cells was less often required in patients with continuation of anticoagulation (80 [13.7%] vs. 130 [17.7%]; OR: 0.59; 95% CI: 0.42 to 0.81; p = 0.001). Kaplan-Meier estimates of survival at 12 months were 85.3% in patients with continuation of anticoagulation and 84.0% in patients with interruption of anticoagulation (hazard ratio: 0.90; 95% CI: 0.73 to 1.12; p = 0.36). CONCLUSIONS: Continuation of oral anticoagulation throughout TAVR did not increase bleeding or vascular complication rates. Moreover, packed red blood cell transfusions were less often required in patients with continuation of oral anticoagulation.

Mechanisms governing avian phylosymbiosis: Genetic dissimilarity based on neutral and MHC regions exhibits little relationship with gut microbiome distributions of Galápagos mockingbirds.

The gut microbiome of animals, which serves important functions but can also contain potential pathogens, is to varying degrees under host genetic control. This can generate signals of phylosymbiosis, whereby gut microbiome composition matches host phylogenetic structure. However, the genetic mechanisms that generate phylosymbiosis and the scale at which they act remain unclear. Two non-mutually exclusive hypotheses are that phylosymbiosis is driven by immunogenetic regions such as the major histocompatibility complex (MHC) controlling microbial composition, or by spatial structuring of neutral host genetic diversity via founder effects, genetic drift, or isolation by distance. Alternatively, associations between microbes and host phylogeny may be generated by their spatial autocorrelation across landscapes, rather than the direct effects of host genetics. In this study, we collected MHC, microsatellite, and gut microbiome data from separate individuals belonging to the Galápagos mockingbird species complex, which consists of four allopatrically distributed species. We applied multiple regression with distance matrices and Bayesian inference to test for correlations between average genetic and microbiome similarity across nine islands for which all three levels of data were available. Clustering of individuals by species was strongest when measured with microsatellite markers and weakest for gut microbiome distributions, with intermediate clustering of MHC allele frequencies. We found that while correlations between island-averaged gut microbiome composition and both microsatellite and MHC dissimilarity existed across species, these relationships were greatly weakened when accounting for geographic distance. Overall, our study finds little support for large-scale control of gut microbiome composition by neutral or adaptive genetic regions across closely related bird phylogenies, although this does not preclude the possibility that host genetics shapes gut microbiome at the individual level.

A quantum liquid of magnetic octupoles on the pyrochlore lattice.

Spin liquids are highly correlated yet disordered states formed by the entanglement of magnetic dipoles1. Theories define such states using gauge fields and deconfined quasiparticle excitations that emerge from a local constraint governing the ground state of a frustrated magnet. For example, the '2-in-2-out' ice rule for dipole moments on a tetrahedron can lead to a quantum spin ice2-4 in rare-earth pyrochlores. However, f-electron ions often carry multipole degrees of freedom of higher rank than dipoles, leading to intriguing behaviours and 'hidden' orders5-6. Here we show that the correlated ground state of a Ce3+-based pyrochlore, Ce2Sn2O7, is a quantum liquid of magnetic octupoles. Our neutron scattering results are consistent with a fluid-like state where degrees of freedom have a more complex magnetization density than that of magnetic dipoles. The nature and strength of the octupole-octupole couplings, together with the existence of a continuum of excitations attributed to spinons, provides further evidence for a quantum ice of octupoles governed by a '2-plus-2-minus' rule7-8. Our work identifies Ce2Sn2O7 as a unique example of frustrated multipoles forming a 'hidden' topological order, thus generalizing observations on quantum spin liquids to multipolar phases that can support novel types of emergent fields and excitations.