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The history of the British Isles and Ireland is characterized by multiple periods of major cultural change, including the influential transformation after the end of Roman rule, which precipitated shifts in language, settlement patterns and material culture1. The extent to which migration from continental Europe mediated these transitions is a matter of long-standing debate2-4. Here we study genome-wide ancient DNA from 460 medieval northwestern Europeans-including 278 individuals from England-alongside archaeological data, to infer contemporary population dynamics. We identify a substantial increase of continental northern European ancestry in early medieval England, which is closely related to the early medieval and present-day inhabitants of Germany and Denmark, implying large-scale substantial migration across the North Sea into Britain during the Early Middle Ages. As a result, the individuals who we analysed from eastern England derived up to 76% of their ancestry from the continental North Sea zone, albeit with substantial regional variation and heterogeneity within sites. We show that women with immigrant ancestry were more often furnished with grave goods than women with local ancestry, whereas men with weapons were as likely not to be of immigrant ancestry. A comparison with present-day Britain indicates that subsequent demographic events reduced the fraction of continental northern European ancestry while introducing further ancestry components into the English gene pool, including substantial southwestern European ancestry most closely related to that seen in Iron Age France5,6.
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Pool de Genes , Migración Humana , Arqueología , ADN Antiguo/análisis , Dinamarca , Inglaterra , Femenino , Francia , Genética de Población , Genoma Humano/genética , Alemania , Historia Medieval , Migración Humana/historia , Humanos , Lenguaje , Masculino , Dinámica Poblacional , Armas/historiaRESUMEN
Understanding and predicting the relationship between leaf temperature (Tleaf) and air temperature (Tair) is essential for projecting responses to a warming climate, as studies suggest that many forests are near thermal thresholds for carbon uptake. Based on leaf measurements, the limited leaf homeothermy hypothesis argues that daytime Tleaf is maintained near photosynthetic temperature optima and below damaging temperature thresholds. Specifically, leaves should cool below Tair at higher temperatures (i.e., > â¼25-30°C) leading to slopes <1 in Tleaf/Tair relationships and substantial carbon uptake when leaves are cooler than air. This hypothesis implies that climate warming will be mitigated by a compensatory leaf cooling response. A key uncertainty is understanding whether such thermoregulatory behavior occurs in natural forest canopies. We present an unprecedented set of growing season canopy-level leaf temperature (Tcan) data measured with thermal imaging at multiple well-instrumented forest sites in North and Central America. Our data do not support the limited homeothermy hypothesis: canopy leaves are warmer than air during most of the day and only cool below air in mid to late afternoon, leading to Tcan/Tair slopes >1 and hysteretic behavior. We find that the majority of ecosystem photosynthesis occurs when canopy leaves are warmer than air. Using energy balance and physiological modeling, we show that key leaf traits influence leaf-air coupling and ultimately the Tcan/Tair relationship. Canopy structure also plays an important role in Tcan dynamics. Future climate warming is likely to lead to even greater Tcan, with attendant impacts on forest carbon cycling and mortality risk.
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Ciclo del Carbono , Carbono , Bosques , Hojas de la Planta , Carbono/metabolismo , Hojas de la Planta/anatomía & histología , Hojas de la Planta/metabolismo , TemperaturaRESUMEN
Background Prostatic artery embolization (PAE) is a safe, minimally invasive angiographic procedure that effectively treats benign prostatic hyperplasia; however, PAE-related patient radiation exposure and associated risks are not completely understood. Purpose To quantify radiation dose and assess radiation-related adverse events in patients who underwent PAE at multiple centers. Materials and Methods This retrospective study included patients undergoing PAE for any indication performed by experienced operators at 10 high-volume international centers from January 2014 to May 2021. Patient characteristics, procedural and radiation dose data, and radiation-related adverse events were collected. Procedural radiation effective doses were calculated by multiplying kerma-area product values by an established conversion factor for abdominopelvic fluoroscopy-guided procedures. Relationships between cumulative air kerma (CAK) or effective dose and patient body mass index (BMI), fluoroscopy time, or radiation field area were assessed with linear regression. Differences in radiation dose stemming from radiopaque prostheses or fluoroscopy unit type were assessed using two-sample t tests and Wilcoxon rank sum tests. Results A total of 1476 patients (mean age, 69.9 years ± 9.0 [SD]) were included, of whom 1345 (91.1%) and 131 (8.9%) underwent the procedure with fixed interventional or mobile fluoroscopy units, respectively. Median procedure effective dose was 17.8 mSv for fixed interventional units and 12.3 mSv for mobile units. CAK and effective dose both correlated positively with BMI (R2 = 0.15 and 0.17; P < .001) and fluoroscopy time (R2 = 0.16 and 0.08; P < .001). No radiation-related 90-day adverse events were reported. Patients with radiopaque implants versus those without implants had higher median CAK (1452 mGy [range, 900-2685 mGy] vs 1177 mGy [range, 700-1959 mGy], respectively; P = .01). Median effective dose was lower for mobile than for fixed interventional systems (12.3 mSv [range, 8.5-22.0 mSv] vs 20.4 mSv [range, 13.8-30.6 mSv], respectively; P < .001). Conclusion Patients who underwent PAE performed with fixed interventional or mobile fluoroscopy units were exposed to a median effective radiation dose of 17.8 mSv or 12.3 mSv, respectively. No radiation-related adverse events at 90 days were reported. © RSNA, 2024 See also the editorial by Mahesh in this issue.
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Embolización Terapéutica , Hiperplasia Prostática , Exposición a la Radiación , Humanos , Masculino , Anciano , Hiperplasia Prostática/diagnóstico por imagen , Hiperplasia Prostática/terapia , Estudios Retrospectivos , Próstata/diagnóstico por imagen , Arterias/diagnóstico por imagenRESUMEN
PURPOSE: To compare prostatic artery embolization (PAE) via transradial access (TRA-PAE) versus transfemoral access (TFA-PAE) to assist access selection. MATERIAL AND METHODS: Procedural outcomes and adverse events were evaluated in 998 patients who underwent PAE at a single center from April 2014 to August 2022; 821 (82%) underwent TRA-PAE (Group R) and 177 (18%) underwent TFA-PAE (Group F). Mean age and prostate size of Groups R and F were 69.2 years (SD ± 8.4) and 117.4 g (SD ± 63.1) and 75.2 years (SD ± 12.1) and 127.2 g (SD ± 83.6), respectively (P < .01 and P = .16; postpropensity matching: P = .38 and P = .35, respectively). Indications for PAE included lower urinary tract symptoms, acute or chronic urinary retention, and hematuria. Procedural and patient-specific metrics were reviewed. Technical success was defined as bilateral PAE. Adverse events were recorded according to the Society of Interventional Radiology (SIR) adverse events classification. Statistical significance was defined as P < .05. RESULTS: Technical success was achieved in 798 (97.2%) patients in Group R and 165 (93.2%) patients in Group F. Mean procedural time, single- and continuous-rotation fluoroscopy time, dose area product, and air kerma were significantly lower in Group R than in Group F (P < .001). Moreover, 6 (0.7%) patients in Group R and 9 (5.5%) patients in Group F had access site ecchymoses, whereas 5 (0.6%) patients in Group R and 6 (3.6%) in Group F had access site hematomas. Two patients experienced transient ischemic attacks (TIAs) after TRA-PAE and recovered without intervention. Two occult radial artery occlusions were noted, but no patient experienced hand ischemia. CONCLUSIONS: In a large single interventional radiologist cohort, TRA-PAE demonstrated similar technical success to that of TFA-PAE with lower access site hemorrhagic complications and radiation requirements; however, TIA and occult radial artery occlusions remain a concern.
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Embolización Terapéutica , Hiperplasia Prostática , Masculino , Humanos , Embolización Terapéutica/efectos adversos , Próstata/irrigación sanguínea , Arteria Femoral/diagnóstico por imagen , Hiperplasia Prostática/diagnóstico por imagen , Hiperplasia Prostática/terapia , Resultado del Tratamiento , Arteria Radial/diagnóstico por imagen , Estudios RetrospectivosRESUMEN
Shifts in vegetation phenology are a key example of the biological effects of climate change1-3. However, there is substantial uncertainty about whether these temperature-driven trends will continue, or whether other factors-for example, photoperiod-will become more important as warming exceeds the bounds of historical variability4,5. Here we use phenological transition dates derived from digital repeat photography6 to show that experimental whole-ecosystem warming treatments7 of up to +9 °C linearly correlate with a delayed autumn green-down and advanced spring green-up of the dominant woody species in a boreal Picea-Sphagnum bog. Results were confirmed by direct observation of both vegetative and reproductive phenology of these and other bog plant species, and by multiple years of observations. There was little evidence that the observed responses were constrained by photoperiod. Our results indicate a likely extension of the period of vegetation activity by 1-2 weeks under a 'CO2 stabilization' climate scenario (+2.6 ± 0.7 °C), and 3-6 weeks under a 'high-CO2 emission' scenario (+5.9 ± 1.1 °C), by the end of the twenty-first century. We also observed severe tissue mortality in the warmest enclosures after a severe spring frost event. Failure to cue to photoperiod resulted in precocious green-up and a premature loss of frost hardiness8, which suggests that vulnerability to spring frost damage will increase in a warmer world9,10. Vegetation strategies that have evolved to balance tradeoffs associated with phenological temperature tracking may be optimal under historical climates, but these strategies may not be optimized for future climate regimes. These in situ experimental results are of particular importance because boreal forests have both a circumpolar distribution and a key role in the global carbon cycle11.
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Aclimatación , Frío , Ecosistema , Calentamiento Global , Calor , Fenómenos Fisiológicos de las Plantas , Dióxido de Carbono/análisis , Dióxido de Carbono/metabolismo , Hielo , Modelos Biológicos , Fotograbar , Desarrollo de la Planta , Estaciones del AñoRESUMEN
Climate change is shifting the phenological cycles of plants1, thereby altering the functioning of ecosystems, which in turn induces feedbacks to the climate system2. In northern (north of 30° N) ecosystems, warmer springs lead generally to an earlier onset of the growing season3,4 and increased ecosystem productivity early in the season5. In situ6 and regional7-9 studies also provide evidence for lagged effects of spring warmth on plant productivity during the subsequent summer and autumn. However, our current understanding of these lagged effects, including their direction (beneficial or adverse) and geographic distribution, is still very limited. Here we analyse satellite, field-based and modelled data for the period 1982-2011 and show that there are widespread and contrasting lagged productivity responses to spring warmth across northern ecosystems. On the basis of the observational data, we find that roughly 15 per cent of the total study area of about 41 million square kilometres exhibits adverse lagged effects and that roughly 5 per cent of the total study area exhibits beneficial lagged effects. By contrast, current-generation terrestrial carbon-cycle models predict much lower areal fractions of adverse lagged effects (ranging from 1 to 14 per cent) and much higher areal fractions of beneficial lagged effects (ranging from 9 to 54 per cent). We find that elevation and seasonal precipitation patterns largely dictate the geographic pattern and direction of the lagged effects. Inadequate consideration in current models of the effects of the seasonal build-up of water stress on seasonal vegetation growth may therefore be able to explain the differences that we found between our observation-constrained estimates and the model-constrained estimates of lagged effects associated with spring warming. Overall, our results suggest that for many northern ecosystems the benefits of warmer springs on growing-season ecosystem productivity are effectively compensated for by the accumulation of seasonal water deficits, despite the fact that northern ecosystems are thought to be largely temperature- and radiation-limited10.
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Desarrollo de la Planta , Fenómenos Fisiológicos de las Plantas , Estaciones del Año , Temperatura , Simulación por Computador , Mapeo Geográfico , Transpiración de Plantas , PlantasRESUMEN
The International Olympic Committee (IOC) recently published a framework on fairness, inclusion, and nondiscrimination on the basis of gender identity and sex variations. Although we appreciate the IOC's recognition of the role of sports science and medicine in policy development, we disagree with the assertion that the IOC framework is consistent with existing scientific and medical evidence and question its recommendations for implementation. Testosterone exposure during male development results in physical differences between male and female bodies; this process underpins male athletic advantage in muscle mass, strength and power, and endurance and aerobic capacity. The IOC's "no presumption of advantage" principle disregards this reality. Studies show that transgender women (male-born individuals who identify as women) with suppressed testosterone retain muscle mass, strength, and other physical advantages compared to females; male performance advantage cannot be eliminated with testosterone suppression. The IOC's concept of "meaningful competition" is flawed because fairness of category does not hinge on closely matched performances. The female category ensures fair competition for female athletes by excluding male advantages. Case-by-case testing for transgender women may lead to stigmatization and cannot be robustly managed in practice. We argue that eligibility criteria for female competition must consider male development rather than relying on current testosterone levels. Female athletes should be recognized as the key stakeholders in the consultation and decision-making processes. We urge the IOC to reevaluate the recommendations of their Framework to include a comprehensive understanding of the biological advantages of male development to ensure fairness and safety in female sports.
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Medicina Deportiva , Deportes , Femenino , Humanos , Masculino , Identidad de Género , Atletas , TestosteronaRESUMEN
Colonially breeding birds and mammals form some of the largest gatherings of apex predators in the natural world and have provided model systems for studying mechanisms of population regulation in animals. According to one influential hypothesis, intense competition for food among large numbers of spatially constrained foragers should result in a zone of prey depletion surrounding such colonies, ultimately limiting their size. However, while indirect and theoretical support for this phenomenon, known as "Ashmole's halo," has steadily accumulated, direct evidence remains exceptionally scarce. Using a combination of vessel-based surveys and Global Positioning System tracking, we show that pelagic seabirds breeding at the tropical island that first inspired Ashmole's hypothesis do indeed deplete their primary prey species (flying fish; Exocoetidae spp.) over a considerable area, with reduced prey density detectable >150 km from the colony. The observed prey gradient was mirrored by an opposing trend in seabird foraging effort, could not be explained by confounding environmental variability, and can be approximated using a mechanistic consumption-dispersion model, incorporating realistic rates of seabird predation and random prey dispersal. Our results provide a rare view of the resource footprint of a pelagic seabird colony and reveal how aggregations of these central-place foraging, marine top predators profoundly influence the oceans that surround them.
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Ecosistema , Conducta Predatoria/fisiología , Animales , Conducta Animal , Evolución Biológica , Aves/fisiología , Conducta Competitiva , Conducta Alimentaria/fisiología , Peces/fisiología , IslasRESUMEN
OBJECTIVES: Rates of cannabis ingestion among young children are increasing. Small studies have evaluated symptomatology of these children. The literature lacks research regarding factors influencing medical management. Our goal was to 1) understand circumstances leading to exposure over time and 2) gain insight into factors that may influence emergency room management and Child Protective Services reporting over time. METHODS: Retrospective cross-sectional study on children younger than 10 years with cannabis-positive urine drug screens in the emergency room setting. Single-factor analysis of variance and Fisher exact tests were used to assess for trends. Two-tailed t tests and Fisher exact tests were used to compare management of children presenting to the emergency room with chief complaint (CC) "ingestion" versus those without. RESULTS: Of the 179 children, the mean age was 3.7 years and 48% were boys. We observed a significant increase over time in cannabis-positive children. The most common location of exposure was the primary residence (54%), with parents as the most frequent users (46%). In the emergency department, the most common CC was ingestion followed by altered mental status and fatigue. Children with an "ingestion" CC were managed with less testing than those with other CCs. They received fewer needle sticks (43% vs 91%), less imaging (5% vs 56% computed tomography heads), and fewer procedures (0% vs 8% lumbar punctures). Children with "ingestion" CC were less likely to be reported to Child Protective Services. CONCLUSIONS: Pediatric cannabis exposures are increasing and have a wide array of clinical presentations that complicate emergency room management. Parental report of cannabis ingestion seems to impact and reduce potentially unnecessary testing.
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Cannabis , Servicios de Protección Infantil , Servicio de Urgencia en Hospital , Humanos , Masculino , Femenino , Estudios Retrospectivos , Estudios Transversales , Preescolar , Niño , Lactante , Detección de Abuso de Sustancias/métodos , Abuso de Marihuana/epidemiología , Abuso de Marihuana/diagnósticoRESUMEN
Mitochondrial supercomplexes form around a conserved core of monomeric complex I and dimeric complex III; wherein a subunit of the former, NDUFA11, is conspicuously situated at the interface. We identified nduf-11 (B0491.5) as encoding the Caenorhabditis elegans homologue of NDUFA11. Animals homozygous for a CRISPR-Cas9-generated knockout allele of nduf-11 arrested at the second larval (L2) development stage. Reducing (but not eliminating) expression using RNAi allowed development to adulthood, enabling characterisation of the consequences: destabilisation of complex I and its supercomplexes and perturbation of respiratory function. The loss of NADH dehydrogenase activity was compensated by enhanced complex II activity, with the potential for detrimental reactive oxygen species (ROS) production. Cryo-electron tomography highlighted aberrant morphology of cristae and widening of both cristae junctions and the intermembrane space. The requirement of NDUF-11 for balanced respiration, mitochondrial morphology and development presumably arises due to its involvement in complex I and supercomplex maintenance. This highlights the importance of respiratory complex integrity for health and the potential for its perturbation to cause mitochondrial disease. This article has an associated First Person interview with Amber Knapp-Wilson, joint first author of the paper.
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Complejo I de Transporte de Electrón , Mitocondrias , Animales , Caenorhabditis elegans , Transporte de Electrón , Complejo I de Transporte de Electrón/genética , Complejo I de Transporte de Electrón/metabolismo , Humanos , Mitocondrias/genética , Mitocondrias/metabolismo , Membranas Mitocondriales/metabolismo , Oxidación-Reducción , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Shifts in the age or turnover time of non-structural carbohydrates (NSC) may underlie changes in tree growth under long-term increases in drought stress associated with climate change. But NSC responses to drought are challenging to quantify, due in part to large NSC stores in trees and subsequently long response times of NSC to climate variation. We measured NSC age (Δ14 C) along with a suite of ecophysiological metrics in Pinus edulis trees experiencing either extreme short-term drought (-90% ambient precipitation plot, 2020-2021) or a decade of severe drought (-45% plot, 2010-2021). We tested the hypothesis that carbon starvation - consumption exceeding synthesis and storage - increases the age of sapwood NSC. One year of extreme drought had no impact on NSC pool size or age, despite significant reductions in predawn water potential, photosynthetic rates/capacity, and twig and needle growth. By contrast, long-term drought halved the age of the sapwood NSC pool, coupled with reductions in sapwood starch concentrations (-75%), basal area increment (-39%), and bole respiration rates (-28%). Our results suggest carbon starvation takes time, as tree carbon reserves appear resilient to extreme disturbance in the short term. However, after a decade of drought, trees apparently consumed old stored NSC to support metabolism.
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Carbono , Pinus , Carbono/metabolismo , Pinus/fisiología , Sequías , Carbohidratos/química , Almidón/metabolismo , Árboles/fisiología , Metabolismo de los Hidratos de CarbonoRESUMEN
In deciduous forests, spring leaf development and fall leaf senescence regulate the timing and duration of photosynthesis and transpiration. Being able to model these dates is therefore critical to accurately representing ecosystem processes in biogeochemical models. Despite this, there has been relatively little effort to improve internal phenology predictions in widely used biogeochemical models. Here, we optimized the phenology algorithms in a regionally developed biogeochemical model (PnET-CN) using phenology data from eight mid-latitude PhenoCam sites in eastern North America. We then performed a sensitivity analysis to determine how the optimization affected future predictions of carbon, water, and nitrogen cycling at Bartlett Experimental Forest, New Hampshire. Compared to the original PnET-CN phenology models, our new spring and fall models resulted in shorter season lengths and more abrupt transitions that were more representative of observations. The new phenology models affected daily estimates and interannual variability of modeled carbon exchange, but they did not have a large influence on the magnitude or long-term trends of annual totals. Under future climate projections, our new phenology models predict larger shifts in season length in the fall (1.1-3.2 days decade-1) compared to the spring (0.9-1.5 days decade-1). However, for every day the season was longer, spring had twice the effect on annual carbon and water exchange totals compared to the fall. These findings highlight the importance of accurately modeling season length for future projections of carbon and water cycling.
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Ecosistema , Tumores Neuroectodérmicos Primitivos , Estaciones del Año , Árboles , Carbono , Bosques , Hojas de la Planta/fisiología , Cambio ClimáticoRESUMEN
BACKGROUND: The spleen is the most commonly injured visceral organ in blunt abdominal trauma. Post-splenectomy infection risk has led to the shift toward spleen preserving procedures and splenic artery embolization (SAE) is now the treatment of choice for hemodynamically stable patients with splenic injury. This study aims to assess the long-term effect of SAE on splenic volume and platelet count. MATERIALS AND METHODS: Using CPT codes, 66 patients who underwent SAE were identified, and 14 of those who had the necessary imaging and laboratory follow-up were included in the study. Indications for SAE were portal hypertension in 8 patients, bleeding in 4 patients, and thrombocytopenia in 1, and one patient had a separate indication. Splenic volume was calculated by automated volumetric software (Aquarius, TeraRecon, Inc.). Paired t-tests were performed to compare splenic volume and platelets before and after SAE. RESULTS: Fourteen patients (7 males, 7 females) with a mean age of 51 ± 11.95 years underwent SAE and were followed by a repeat computed tomography scan at an average of 733.57 days. Nine SAEs were performed using vascular plugs, 3 using micro coils, and 2 out of that were with Gelfoam slurry, and 2 using coils only. All embolizations were technically successful with complete cessation of flow. Mean splenic volumes pre- and post-SAE were 903.5 ± 523.73 cm3 and 746.5 ± 511.95 cm3, respectively, representing a mean decrease of 8.31% compared to baseline [P = 0.346]. Minimum platelet counts (x103) pre-SAE (within 3 months) and post-SAE (2 weeks to 3 months after the procedure) were 55.79 ± 57.11 and 116 ± 145.40, respectively. The minimum platelet count showed a statistically significant mean increase of 134.92% (P = 0.033). CONCLUSIONS: The splenic volume is not altered significantly by SAE in the long term. Similarly, the platelet count is also not significantly altered at 3 months follow-up. This study, although small, suggests that SAE is a safe intervention that can preserve splenic volume and function in the long term.
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Embolización Terapéutica , Heridas no Penetrantes , Masculino , Femenino , Humanos , Adulto , Persona de Mediana Edad , Bazo/diagnóstico por imagen , Bazo/irrigación sanguínea , Bazo/lesiones , Recuento de Plaquetas , Arteria Esplénica/diagnóstico por imagen , Resultado del Tratamiento , Estudios Retrospectivos , Embolización Terapéutica/efectos adversos , Embolización Terapéutica/métodos , Heridas no Penetrantes/diagnóstico por imagen , Heridas no Penetrantes/terapia , Heridas no Penetrantes/etiologíaRESUMEN
Urbanization has caused environmental changes, such as urban heat islands (UHIs), that affect terrestrial ecosystems. However, how and to what extent urbanization affects plant phenology remains relatively unexplored. Here, we investigated the changes in the satellite-derived start of season (SOS) and the covariation between SOS and temperature (RT ) in 85 large cities across the conterminous United States for the period 2001-2014. We found that 1) the SOS came significantly earlier (6.1 ± 6.3 d) in 74 cities and RT was significantly weaker (0.03 ± 0.07) in 43 cities when compared with their surrounding rural areas (P < 0.05); 2) the decreased magnitude in RT mainly occurred in cities in relatively cold regions with an annual mean temperature <17.3 °C (e.g., Minnesota, Michigan, and Pennsylvania); and 3) the magnitude of urban-rural difference in both SOS and RT was primarily correlated with the intensity of UHI. Simulations of two phenology models further suggested that more and faster heat accumulation contributed to the earlier SOS, while a decrease in required chilling led to a decline in RT magnitude in urban areas. These findings provide observational evidence of a reduced covariation between temperature and SOS in major US cities, implying the response of spring phenology to warming conditions in nonurban environments may decline in the warming future.
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Desarrollo de la Planta , Urbanización , Ciudades , Cambio Climático , Ecosistema , Calor , Estaciones del Año , Estados UnidosRESUMEN
OBJECTIVE: To model the financial impact of policies governing the scheduling of overlapping surgeries, and to identify optimal solutions that maximize operating efficiency that satisfy the fiduciary duty to patients. BACKGROUND: Hospitals depend on procedural revenue to maintain financial health as the recent pandemic has revealed. Proposed policies governing the scheduling of overlapping surgeries may dramatically impact hospital revenue. To date, the potential financial impact has not been modeled. METHODS: A linear forecasting model based on a logic matrix decision tree enabled an analysis of surgeon productivity annualized over a fiscal year. The model applies procedural and operational variables to policy constraints limiting surgical scheduling. Model outputs included case and financial metrics modeled over 1000-surgeon-year simulations. case metrics included annual case volume, case mix, operating room (OR) utilization, surgeon utilization, idle time, and staff overtime hours. Financial outputs included annual revenue, expenses, and contribution margin. RESULTS: The model was validated against surgical data. case and financial metrics decreased as a function of increasingly restrictive scheduling scenarios, with the greatest contribution margin loses ($1,650,000 per surgeon-year) realized with the introduction of policies mandating that a second patient could not enter the OR until the critical portion of the first surgery was completed. We identify an optimal scheduling scenario that maximizes surgeon efficiency, minimizes OR idle time and revenue loses, and satisfies ethical obligations to patients. CONCLUSIONS: Hospitals may expect significant financial loses with the introduction of policies restricting OR scheduling. We identify an optimal solution that maximizes efficiency while satisfying ethical duty to patients. This forecast is immediately relevant to any hospital system that depends upon procedural revenue.
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Quirófanos , Políticas , Predicción , Accesibilidad a los Servicios de Salud , Hospitales , HumanosRESUMEN
Wood formation determines major long-term carbon (C) accumulation in trees and therefore provides a crucial ecosystem service in mitigating climate change. Nevertheless, we lack understanding of how species with contrasting wood anatomical types differ with respect to phenology and environmental controls on wood formation. In this study, we investigated the seasonality and rates of radial growth and their relationships with climatic factors, and the seasonal variations of stem nonstructural carbohydrates (NSC) in three species with contrasting wood anatomical types (red oak: ring-porous; red maple: diffuse-porous; white pine: coniferous) in a temperate mixed forest during 2017-2019. We found that the high ring width variability observed in both red oak and red maple was caused more by changes in growth duration than growth rate. Seasonal radial growth patterns did not vary following transient environmental factors for all three species. Both angiosperm species showed higher concentrations and lower inter-annual fluctuations of NSC than the coniferous species. Inter-annual variability of ring width varied by species with contrasting wood anatomical types. Due to the high dependence of annual ring width on growth duration, our study highlights the critical importance of xylem formation phenology for understanding and modelling the dynamics of wood formation.
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Pinus , Quercus , Tracheophyta , Carbohidratos , Ecosistema , Estaciones del Año , Madera , XilemaRESUMEN
Whether sources or sinks control wood growth remains debated with a paucity of evidence from mature trees in natural settings. Here, we altered carbon supply rate in stems of mature red maples (Acer rubrum) within the growing season by restricting phloem transport using stem chilling; thereby increasing carbon supply above and decreasing carbon supply below the restrictions, respectively. Chilling successfully altered nonstructural carbon (NSC) concentrations in the phloem without detectable repercussions on bulk NSC in stems and roots. Ring width responded strongly to local variations in carbon supply with up to seven-fold differences along the stem of chilled trees; however, concurrent changes in the structural carbon were inconclusive at high carbon supply due to large local variability of wood growth. Above chilling-induced bottlenecks, we also observed higher leaf NSC concentrations, reduced photosynthetic capacity, and earlier leaf coloration and fall. Our results indicate that the cambial sink is affected by carbon supply, but within-tree feedbacks can downregulate source activity, when carbon supply exceeds demand. Such feedbacks have only been hypothesized in mature trees. Consequently, these findings constitute an important advance in understanding source-sink dynamics, suggesting that mature red maples operate close to both source- and sink-limitation in the early growing season.
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Acer , Madera/fisiología , Fotosíntesis , Árboles/fisiología , Carbono/análisis , Hojas de la Planta/fisiologíaRESUMEN
BACKGROUND: Prostate artery embolization (PAE) is an emerging therapy for lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH). AIM: This retrospective study was conducted to assess the effect of prostate artery embolization (PAE) on erectile function in a cohort of patients with LUTS attributable to BPH at 3-months after the procedure. METHODS: A retrospective review was performed on 167 patients who underwent PAE. Data collected included Sexual Health Inventory in Men (SHIM) scores at 3, 6, and 12 months post-PAE, in conjunction with the International Prostate Symptom Scores (IPSS), Quality of Life (QoL) scores, and prostate volumes. Primary outcome was erectile function as assessed by SHIM scores at 3 months after PAE. An analysis was performed to identify patients with a ±5-point SHIM change to group them according to this minimum clinically significant difference in erectile function. Adverse events were recorded using the Clavien-Dindo (CD) classification. OUTCOMES: At 3 months following PAE, median IPSS decreased by 16.0 [IQR, 9.0-22.0] points, median QOL decreased by 4.0 [IQR, 2.0-5.0] points, and median prostate volume decreased by 33 g [IQR, 14-55]. RESULTS: Median SHIM score was 17.0 [IQR, 12.0-22.0] at baseline, 18.0 [IQR, 14.0-23.0] at 3 months [P = .031], 19.0 [IQR, 14.5-21.5] at 6 months [P = .106] and 20 [IQR, 16.0-24.0] at 12 months [P = .010] following PAE. In patients with no erectile dysfunction (ED) at baseline, 21% (n = 9) reported some degree of decline in erectile function post-PAE. However, 38% (n = 40) of patients who presented with mild-to-moderate ED reported improvement in their erectile function 3 months following PAE. Overall, the changes in baseline SHIM score were relatively small; 82% (n = 137) of patients did not have more than 5 points of change in their SHIM scores at 3 months following PAE. CLINICAL IMPLICATIONS: Our findings suggest PAE has no adverse impact on erectile function for most patients. STRENGTHS & LIMITATIONS: The study was performed at a single center with 1 operator's experience, and is retrospective with no control group. CONCLUSION: Findings suggest that prostate artery embolization has no adverse effect on erectile function in the majority of patients with LUTS attributable to BPH at 3 months after the procedure. Bhatia S, Acharya V, Jalaeian H, et al., Effect of Prostate Artery Embolization on Erectile Function - A Single Center Experience of 167 Patients. J Sex Med 2022;19:594-602.
Asunto(s)
Disfunción Eréctil , Síntomas del Sistema Urinario Inferior , Hiperplasia Prostática , Arterias , Disfunción Eréctil/complicaciones , Disfunción Eréctil/terapia , Humanos , Síntomas del Sistema Urinario Inferior/complicaciones , Síntomas del Sistema Urinario Inferior/terapia , Masculino , Próstata , Hiperplasia Prostática/complicaciones , Hiperplasia Prostática/terapia , Calidad de Vida , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Diverse organisms, from insects to humans, actively seek out sensory information that best informs goal-directed actions. Efficient active sensing requires congruity between sensor properties and motor strategies, as typically honed through evolution. However, it has been difficult to study whether active sensing strategies are also modified with experience. Here, we used a sensory brain-machine interface paradigm, permitting both free behavior and experimental manipulation of sensory feedback, to study learning of active sensing strategies. Rats performed a searching task in a water maze in which the only task-relevant sensory feedback was provided by intracortical microstimulation (ICMS) encoding egocentric bearing to the hidden goal location. The rats learned to use the artificial goal direction sense to find the platform with the same proficiency as natural vision. Manipulation of the acuity of the ICMS feedback revealed distinct search strategy adaptations. Using an optimization model, the different strategies were found to minimize the effort required to extract the most salient task-relevant information. The results demonstrate that animals can adjust motor strategies to match novel sensor properties for efficient goal-directed behavior.