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A Panchromatic View of the Bulge Globular Cluster NGC 6569
Get PDFWe used high-resolution optical HST/WFC3 and multi-conjugate adaptive optics assisted GEMINI GeMS/GSAOI observations in the near-infrared to investigate the physical properties of the globular cluster NGC 6569 in the Galactic bulge. We have obtained the deepest purely NIR color-magnitude diagram published so far for this cluster using ground-based observations, reaching ≈ 21.0 mag (two magnitudes below the main-sequence turn-off point). By combining the two datasets secured at two different epochs, we determined relative proper motions for a large sample of individual stars in the center of NGC 6569, allowing a robust selection of cluster member stars. Our proper motion analysis solidly demonstrates that, despite its relatively high metal content, NGC 6569 hosts some blue horizontal branch stars. A differential reddening map has been derived in the direction of the system, revealing a maximum color excess variation of about ~ 0.12 mag in the available field of view. The absolute age of NGC 6569 has been determined for the first time. In agreement with the other few bulge globular clusters with available age estimates, NGC 6569 turns out to be old, with an age of about 12.8 Gyr, and a typical uncertainty of 0.8-1.0 Gyr
Spatially Variable Increase in Rock Uplift in the Northern U.S. Cordillera Recorded in the Distribution of River Knickpoints and Incision Depths
Get PDFLandscape evolution is driven by factors like tectonics and climate, and unraveling such factors can reveal the history recorded in landscape morphology. The northern U.S. Cordillera features many potential drivers, such as the Yellowstone plume, the extrusion of a large igneous province, and the drainage of large lakes. Among this complex geologic history, the drivers of transient incision in the Clearwater and Salmon watersheds of central Idaho are not well understood. To constrain the pattern of regional incision, we analyze the morphologies of 80 individual tributaries underlain by single lithologies. From north to south across our study area, knickpoint elevations increase from about 800 to 2,200 m, and incision depths increase from about 300 to 1,200 m. We use both numerical and analytical models to demonstrate that such a gradient could represent spatial variations in rock uplift. These findings suggest that transience is driven by a spatially variable increase in rock uplift that has disrupted a low‐relief paleolandscape, and the high steepness values of main drainages suggest that high rock‐uplift rates are still maintained to the present. Changes in rock uplift may be related to interactions between the Yellowstone plume and the lithosphere, although base level fall from the drainage of the Lake Idaho down the proto‐Snake River may be superimposed over these patterns in rock uplift. We show that careful, quantitative analyses of river profiles in geologically complex regions can differentiate between the influences of rock uplift and far‐field base level changes
¿Vales educativos suponen una mejor educación? Nuevas investigaciones dejan interrogantes
Get PDFDurante las últimas dos décadas, proponentes de los vales para escuelas privadas han estado impulsando la idea de que los vales funcionan
« Elle dansa et plut à Hérode » : les arts d’incarner Salomé
Get PDFLe thème de la danse de Salomé, négligé par l’iconographie traditionnelle au profit de l’image édifiante de la tête coupée de Jean-Baptiste, a connu un rayonnement esthétique prodigieux à partir des années 1870 et jusqu’au début du xxe siècle. La fascination suscitée par ce thème, réduit à un couple de syntagmes verbaux dans ses sources bibliques (« elle dansa, et plut » [Marc vi, 22]), a ainsi engendré un foisonnement textuel, visuel, théâtral, musical, chorégraphique, etc. ; depuis l’Hérodias de Flaubert jusqu’à la « danse des sept voiles » dans l’opéra de Strauss et au-delà, en passant par les Salomé de Moreau, de Wilde, de Loïe Fuller, parmi d’autres. Cet article examine certains procédés transartistiques qui ont permis au corps de Salomé, anonyme et dépouillé dans les Évangiles, de devenir l’un des principaux foyers de correspondances entre les arts, à l’origine du symbolisme
RISING FROM FAILURE, STAYING DOWN, OR MORE OF THE SAME? AN INDUCTIVE STUDY OF ENTREPRENEURIAL REENTRY
Get PDFDrawing on a multi-year qualitative study, we explore the phenomenon of reentry into venturing after a failure. The primary discovery of this study is a pathway by which interactions of failure attributions and emotions lead to effective entrepreneurial reentry in the aftermath of a failure. Specifically, we discover three trajectories of reentry: separation (reentry with minimal modifications), reinforcement (no reentry), and metamorphosis (reentry with substantial modifications). We describe the differences between the trajectories and detail three dimensions of primary discovery: negative emotions are not necessarily an obstacle to reentry, as previously thought; perceived controllability is critical in explaining reentry; and the evolution of attributional/emotional responses over time as a result of the interplay between these concepts is central to explaining effective reentry
Circumventing Standing to Appeal
Get PDFThe requirement of standing to sue in federal court is familiar, but the related requirement of standing to appeal within the Article III judiciary is badly undertheorized. The Supreme Court’s opinions suggest (at least) four constitutional rationales. Standing to appeal might serve the same functional purposes as standing to sue, or it might follow from the fact that appeals involve two separate courts, or it might be triggered because the underlying case or controversy has become moot, or because it has reached the point of final judgment. Compounding the confusion, the requirement of standing to appeal can have troubling consequences in the cases in which it arises most frequently: when state officials refuse to defend state law against constitutional attack and decline to appeal from an adverse judgment. In an era of political polarization, state attorneys general increasingly find it tempting to abandon the defense of laws supported by the opposing party. Standing doctrine makes that situation worse, affording state officials the opportunity to short-circuit appellate review for self-serving or partisan reasons. After critically examining the possible constitutional theories, this Article concludes that the requirement of standing to appeal is best explained by the finality of the judgment and the conclusion of the underlying “case” or “controversy.” On that account, however, Congress is not powerless to facilitate appellate review, even in the absence of an appeal by an injured party. Congress plays a primary role in determining when a legal judgment becomes final, and it already postpones the point of finality through a wide range of procedural devices. Consistent with the Constitution, Congress could provide for automatic appeals by operation of statute, for example, whenever a district court enters an injunction against the enforcement of state law, or for judge-initiated appeals in the discretion of the appellate court, on its own motion or at the suggestion of the district court or a party
Thioallenoates in Catalytic Enantioselective [2+2]-Cycloadditions with Unactivated Alkenes
No full textThe application of thioallenoates to catalytic enantioselective [2+2]-cycloadditions with unactivated alkenes is reported.In many cases, the thioallenoates examined exhibit superior reactivity and selectivity compared to the alkoxy analogs generally used in these cycloadditions
Effects of 10 yr of nitrogen and phosphorus fertilization on carbon and nutrient cycling in a tidal freshwater marsh
No full textTidal freshwater marshes can protect downstream ecosystems from eutrophication by intercepting excess nutrient loads, but recent studies in salt marshes suggest nutrient loading compromises their structural and functional integrity. Here, we present data on changes in plant biomass, microbial biomass and activity, and soil chemistry from plots in a tidal freshwater marsh on the Altamaha River (GA) fertilized for 10 yr with nitrogen (+N), phosphorus (+P), or nitrogen and phosphorus (+NP). Nitrogen alone doubled aboveground biomass and enhanced microbial activity, specifically rates of potential nitrification, denitrification, and methane production measured in laboratory incubations. Phosphorus alone increased soil P and doubled microbial biomass but did not affect microbial processes. Nitrogen or P alone decreased belowground biomass and soil carbon (C) whereas +NP increased aboveground biomass, microbial biomass and N cycling, and N, P, and C assimilation and burial more than either nutrient alone. Our findings suggest differential nutrient limitation of tidal freshwater macrophytes by N and microbes by P, similar to what has been observed in salt marshes. Macrophytes outcompete microbes for P in response to long-term N and P additions, leading to increased soil C storage through increased inputs of belowground biomass relative to N and P added singly. The susceptibility of tidal freshwater marshes to long-term nutrient enrichment and, hence their ability to mitigate eutrophication will depend on the quantity and relative proportion of N vs. P entering estuaries and tidal wetlands
The Influence of Harm Avoidance and Impulsivity on Delay Discounting Rates
No full textHigh rates of delay discounting are associated with a range of disorders characterized by behavioral disinhibition, such as substance abuse and childhood behavioral problems. The current study extends the research of the personality correlates of delay discounting by examining its association with two domains of disinhibited personality, impulsivity and low harm avoidance. Trait measures of impulsivity and harm avoidance as well as a delay discounting task were administered to 669 young adult subjects (350 male, 319 female). The primary hypothesis was that a combination of high impulsivity and low harm avoidance would be associated with the highest delay discounting rates. Delay discounting rates were significantly associated with high levels of impulsivity. Counterintuitively, the highest rates of delay discounting were associated with high rates of impulsivity and high rates of harm avoidance. Results suggest that those high in impulsivity and harm avoidance are more sensitive to immediate rewards. These results are novel and suggest more complex processes involved when considering a choice between an immediate and a delayed reward that may require longer waiting periods, which itself may be anxiety providing and perceived as potentially harmful
Social Relationships and Risk of Type 2 Diabetes Among Postmenopausal Women
No full textObjectives: We examined whether social relationship variables (social support, social strain, social network size, and stressful life events) were associated with risk of developing type 2 diabetes among postmenopausal women. Method: 139,924 postmenopausal women aged 50–79 years without prevalent diabetes at baseline were followed for a mean of 14 years. 19,240 women developed diabetes. Multivariable Cox proportional hazard models tested associations between social relationship variables and diabetes incidence after consideration of demographics, depressive symptoms, and lifestyle behaviors. We also examined moderating effects of obesity and race/ethnicity, and we tested whether social variable associations were mediated by lifestyle or depressive symptoms. Results: Compared with the lowest quartile, women in the highest social support quartile had lower risk of diabetes after adjusting for demographic factors, health behaviors, and depressive symptoms (hazard ratio [HR] = 0.93, 95% confidence interval [CI] = 0.89–0.97). Social strain (HR = 1.09, 95% CI = 1.04–1.13) and stressful life events (HR = 1.10, 95% CI = 1.05–1.15) were associated with higher diabetes risks. The association between diabetes and social strain was stronger among African American women. Social relationship variables had direct relationships to diabetes, as well as indirect effects partially mediated by lifestyle and depressive symptoms. Discussion: Social support, social strain, and stressful life events were associated with diabetes risk among postmenopausal women independently of demographic factors and health behaviors. In addition to healthy behaviors such as diet and physical activity, healthy social relationships among older women may be important in the prevention of diabetes