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1.
Entropy (Basel) ; 23(10)2021 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-34682005

RESUMEN

Generative modelling is an important unsupervised task in machine learning. In this work, we study a hybrid quantum-classical approach to this task, based on the use of a quantum circuit born machine. In particular, we consider training a quantum circuit born machine using f-divergences. We first discuss the adversarial framework for generative modelling, which enables the estimation of any f-divergence in the near term. Based on this capability, we introduce two heuristics which demonstrably improve the training of the born machine. The first is based on f-divergence switching during training. The second introduces locality to the divergence, a strategy which has proved important in similar applications in terms of mitigating barren plateaus. Finally, we discuss the long-term implications of quantum devices for computing f-divergences, including algorithms which provide quadratic speedups to their estimation. In particular, we generalise existing algorithms for estimating the Kullback-Leibler divergence and the total variation distance to obtain a fault-tolerant quantum algorithm for estimating another f-divergence, namely, the Pearson divergence.

2.
Front Vet Sci ; 8: 629410, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33834047

RESUMEN

To better tackle diseases and sustain healthy ecosystems, One Health programs must efficiently bridge health in humans, domestic/livestock species, wild animals and plants, agriculture/aquaculture, and the environment. The Smithsonian Institution proposes to address this by considering 'health' in a broad sense - the absence of undue pathogens and unnecessary stress for any organisms as well as access to good living conditions in functional environments. Considering the interconnectedness of all life forms, the Smithsonian plans to create a framework that will integrate cultural, social, and educational components into health research on humans, animals, plants, or ecosystems. The objectives of this perspective article are to (1) propose an innovative framework to support an interconnected/integrated approach to health and (2) provide examples fostering impactful collaborations on One Health research and education. Based on the core strengths of the Smithsonian (multidisciplinary research, outreach and education programs, libraries/archives, and collections) and central institutional support, this framework has the potential to extend existing health-related projects, address new needs and situations (e.g., response to pandemics), provide invaluable resources to inform policy and decision makers, and educate all audiences globally.

3.
Artículo en Inglés | MEDLINE | ID: mdl-31336749

RESUMEN

Chronic diseases have added to the economic burden of the U.S. healthcare system. Most Americans spend most of their waking time at work, thereby, presenting employers with an opportunity to protect and promote health. The purpose of this study was to assess the implementation of workplace health governance and safety strategies among worksites in the State of Nebraska, over time and by industry sector using a randomized survey. Weighted percentages were compared by year, industry sector, and worksite size. Over the three study periods, 4784 responses were collected from worksite representatives. Adoption of workplace health governance and planning strategies increased over time and significantly varied across industry sector groups. Organizational safety policies varied by industry sector and were more commonly reported than workplace health governance and planning strategies. Time constraints were the most common barrier among worksites of all sizes, and stress was reported as the leading employee health issue that negatively impacts business. Results suggest that opportunities exist to integrate workplace health and safety initiatives, especially in blue-collar industry sectors and small businesses.


Asunto(s)
Promoción de la Salud , Servicios de Salud del Trabajador , Salud Laboral , Lugar de Trabajo , Comercio/estadística & datos numéricos , Promoción de la Salud/métodos , Humanos , Industrias , Nebraska , Política Organizacional , Pequeña Empresa , Encuestas y Cuestionarios , Lugar de Trabajo/organización & administración
4.
Environ Health Insights ; 13: 1178630219839016, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31168292

RESUMEN

Mini-grant programs are an increasingly popular method for outside organizations (eg, non-profits, state agencies) to support wellness initiatives. However, little is known about mini-grant programs in worksites. The present study explored the implementation and outcomes of a worksite wellness mini-grant program. Semi-structured interviews were conducted with 12 wellness champions representing 12 worksites that were involved in a mini-grant program over a 4-year span. Interviews focused on general use, barriers and facilitators, and outcomes of the mini-grant initiatives. Mini-grants were generally used to support a short-term activity, such as purchasing food, which was not allowed per grant funding, or supporting a one-time event-this type of use diverged from recommended use of funds. Participants reported that outcomes from the mini-grant initiates were largely positive, highlighting culture shifts and increased awareness/perception of employer support for wellness. Barriers included culture (eg, employee attitudes, motivation), environment (eg, infrastructure, weather), and worksite characteristics (eg, multiple locations, number of employees), while facilitators included employee interest and involvement, established wellness culture, awareness and accessibility (eg, providing options, education), and support (eg, employer support, support from outside organizations). There was overlap between certain barriers and facilitators, indicating key areas of focus for future research and mini-grant programs.

5.
J Phys Act Health ; 15(10): 730-736, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29741448

RESUMEN

BACKGROUND: The purpose of this study was to determine if the Go Nutrition and Physical Activity Self-Assessment in Child Care (Go NAP SACC) intervention was effective in improving best practices in the areas of infant and child physical activity and outdoor play and learning in family child care homes (FCCHs) in Nebraska. METHODS: FCCHs (n = 201) participated in a pre-post evaluation using the Infant and Child Physical Activity and Outdoor Play and Learning assessments from the Go NAP SACC validated measure to assess compliance with best practices. RESULTS: At post, FCCHs demonstrated significant differences in 85% of the Infant and Child Physical Activity items (17 of 20) and 80% of the Outdoor Play and Learning items (12 of 15). Significant differences in best practices between urban and rural FCCH providers were also found. CONCLUSION: Go NAP SACC appears to be an effective intervention in Nebraska as, after participation in the initiative, providers were improving child care physical activity best practices. Additional research is needed to objectively determine if these changes resulted in objective improvements in children's physical activity levels. Further, efforts are needed to develop and/or identify geographic-specific resources for continued improvement.


Asunto(s)
Cuidado del Niño/métodos , Guarderías Infantiles/estadística & datos numéricos , Salud Infantil/estadística & datos numéricos , Ejercicio Físico , Estado Nutricional , Evaluación de Programas y Proyectos de Salud , Preescolar , Femenino , Humanos , Lactante , Masculino , Nebraska , Población Rural , Autoevaluación (Psicología)
6.
Ecol Evol ; 8(2): 841-851, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29375758

RESUMEN

Species distribution models (SDM) can be valuable for identifying key habitats for conservation management of threatened taxa, but anthropogenic habitat change can undermine SDM accuracy. We used data for the Red Siskin (Spinus cucullatus), a critically endangered bird and ground truthing to examine anthropogenic habitat change as a source of SDM inaccuracy. We aimed to estimate: (1) the Red Siskin's historic distribution in Venezuela; (2) the portion of this historic distribution lost to vegetation degradation; and (3) the location of key habitats or areas with both, a high probability of historic occurrence and a low probability of vegetation degradation. We ground-truthed 191 locations and used expert opinion as well as landscape characteristics to classify species' habitat suitability as excellent, good, acceptable, or poor. We fit a Random Forest model (RF) and Enhanced Vegetation Index (EVI) time series to evaluate the accuracy and precision of the expert categorization of habitat suitability. We estimated the probability of historic occurrence by fitting a MaxLike model using 88 presence records (1960-2013) and data on forest cover and aridity index. Of the entire study area, 23% (20,696 km2) had a historic probability of Red Siskin occurrence over 0.743. Furthermore, 85% of ground-truthed locations had substantial reductions in mean EVI, resulting in key habitats totaling just 976 km2, in small blocks in the western and central regions. Decline in Area of Occupancy over 15 years was between 40% and 95%, corresponding to an extinction risk category between Vulnerable and Critically Endangered. Relating key habitats with other landscape features revealed significant risks and opportunities for proposed conservation interventions, including the fact that ongoing vegetation degradation could limit the establishment of reintroduced populations in eastern areas, while the conservation of remaining key habitats on private lands could be improved with biodiversity-friendly agri- and silviculture programs.

7.
Science ; 337(6092): 292; author reply 292, 2012 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-22822134

RESUMEN

Kelley and Endler (Reports, 20 January 2012, p. 335) claim that male great bowerbirds construct a visual illusion, using display object gradients, that affects mating success. We argue that they provide inadequate statistical support for their hypothesis, inappropriately exclude important data, and do not consider other display traits that explain mating success. We propose a more plausible alternative hypothesis to explain display object patterns.


Asunto(s)
Preferencia en el Apareamiento Animal , Ilusiones Ópticas , Passeriformes/fisiología , Conducta Sexual Animal , Animales , Femenino , Masculino
8.
J Exp Biol ; 215(Pt 7): 1090-105, 2012 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-22399654

RESUMEN

Variation in visual spectral tuning has evolved in concert with signal colour in some taxa, but there is limited evidence of this pattern in birds. To further investigate this possibility, we compared spectral sensitivity among bowerbird species that occupy different visual habitats and are highly diverged in plumage and decoration colour displays, which are important in mate choice and possibly reproductive isolation. Microspectrophotometry of violet-, short-, medium- and long-wavelength-sensitive cones revealed no significant interspecific variation in visual pigment peak spectral absorbance values that ranged between 404-410, 454, 503-511 and 558-568 nm, respectively. Mean cut-off wavelength values for C-, Y-, R- and P-type coloured oil droplets were 418-441, 508-523, 558-573 and 412-503 nm, respectively, with values at longer wavelengths in ventral compared with dorsal retina cones. Low ocular media mid-wavelength transmission values (340-352 nm) suggest that bowerbirds may represent a transitional stage in the evolution from the ancestral violet-sensitive- to the derived ultraviolet-sensitive-type short-wavelength-sensitive-1-based visual system found in younger passerine lineages. Sequence data obtained for rod opsin and four cone opsin genes were identical at key tuning sites, except for an interspecific leucine-52-alanine polymorphism in the short-wavelength-sensitive 2 opsin. There was no obvious relationship between relative proportions of cone classes and either visual habitat or display colour. Overall, we detected little interspecific variation in bowerbird spectral sensitivity and no association between sensitivity and display diversity, which is consistent with the general trend among avian taxa.


Asunto(s)
Sensibilidad de Contraste/fisiología , Microespectrofotometría , Passeriformes/fisiología , Pigmentación/fisiología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Color , Ecosistema , Opsinas/química , Opsinas/genética , Fotoblanqueo , Células Fotorreceptoras Retinianas Conos/metabolismo , Especificidad de la Especie
9.
Vasc Endovascular Surg ; 45(2): 178-80, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21278171

RESUMEN

Acute radiation syndrome or radiation sickness is a serious illness that occurs after the body receives a high dose of radiation, typically over a short period of time. This condition may be underrecognized by interventionalists and must be considered whenever performing complex endovascular procedures.


Asunto(s)
Síndrome de Radiación Aguda/etiología , Aneurisma de la Aorta Abdominal/cirugía , Aortografía/efectos adversos , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Radiografía Intervencional/efectos adversos , Anciano , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Implantación de Prótesis Vascular/efectos adversos , Procedimientos Endovasculares/efectos adversos , Fluoroscopía , Humanos , Masculino , Dosis de Radiación , Radiodermatitis/etiología , Medición de Riesgo
10.
Vascular ; 17(6): 359-64, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19909685

RESUMEN

Isolated dissection of the origin of both celiac and superior mesenteric arteries is a rare vascular pathology with limited management guidelines. The presentation is generally nonspecific, most often manifesting with epigastric pain radiating to the back. A high diagnostic index of suspicion and stepwise management are essential for a successful outcome. This case report details the clinical course of a 57-year-male who presented with a 2-week history of epigastric discomfort with back pain and was found to have focal celiac artery dissection with aneurysmal dilation of 1.2 cm. His vital signs were stable, and the physical examination was unremarkable. At this time, he was placed on antiplatelet medication and was scheduled for endovascular repair of his celiac aneurysm with a covered stent graft. Two weeks later, recurrent abdominal pain prompted a repeat computed tomographic scan that revealed sequential superior mesenteric artery (SMA) dissection. The patient was admitted and anticoagulated. A complete workup ruled out underlying collagen vascular and autoimmune pathology. He remained stable, with significant symptomatic improvement. After 6 months, anticoagulation was discontinued and antiplatelet therapy was instituted for long-term management. Subsequent operative or endovascular intervention was not required. The patient was continuing to do well on his 18-month clinical follow-up. There are 71 cases of SMA and 12 cases of celiac artery dissection in the literature. This report outlines this rare presentation of isolated, proximal sequential celiac artery and SMA dissection. This case illustrates that conservative management may be warranted in uncomplicated, isolated visceral arterial dissection.


Asunto(s)
Anticoagulantes/administración & dosificación , Disección Aórtica/tratamiento farmacológico , Arteria Celíaca , Arteria Mesentérica Superior , Inhibidores de Agregación Plaquetaria/administración & dosificación , Dolor Abdominal/etiología , Disección Aórtica/complicaciones , Disección Aórtica/diagnóstico , Dolor de Espalda/etiología , Arteria Celíaca/diagnóstico por imagen , Esquema de Medicación , Humanos , Masculino , Arteria Mesentérica Superior/diagnóstico por imagen , Persona de Mediana Edad , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Ultrasonografía
11.
Biol Lett ; 3(5): 463-6, 2007 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-17623632

RESUMEN

Males in many bird species mimic the vocalizations of other species during sexual displays, but the evolutionary and functional significance of interspecific vocal mimicry is unclear. Here we use spectrographic cross-correlation to compare mimetic calls produced by male satin bowerbirds (Ptilonorhynchus violaceus) in courtship with calls from several model species. We show that the accuracy of vocal mimicry and the number of model species mimicked are both independently related to male mating success. Multivariate analyses revealed that these mimetic traits were better predictors of male mating success than other male display traits previously shown to be important for male mating success. We suggest that preference-driven mimetic accuracy may be a widespread occurrence, and that mimetic accuracy may provide females with important information about male quality. Our findings support an alternative hypothesis to help explain a common element of male sexual displays.


Asunto(s)
Aves/fisiología , Conducta Sexual Animal , Vocalización Animal , Animales , Evolución Biológica , Femenino , Masculino
12.
J Psychosom Res ; 63(1): 83-91, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17586341

RESUMEN

OBJECTIVES: (1) To assess the overall performance of the Hospital Anxiety and Depression Scale (HADS) as a screening instrument to identify cases of major depressive disorder (MDD) in mixed cancer outpatients. (2) To determine the sensitivity and specificity of various HADS cut-off scores. (3) To recommend an optimal HADS cut-off score for use in this population. METHODS: A cross-sectional questionnaire and interview survey of consecutive patients attending outpatient clinics in a regional cancer centre in Edinburgh, Scotland, United Kingdom. RESULTS: Thirty (8.3%) of 361 patients met criteria for MDD at interview. With the use of the total HADS score to identify these cases of MDD, the area under the receiver operating characteristic curve was 0.94 (95% CI, 0.91-0.97). A cut-off of 14/15 gave a sensitivity of 0.87 (95% CI, 0.70-0.95), a specificity of 0.85 (95% CI, 0.81-0.89), and a positive predictive value of 0.35, and was considered optimal. CONCLUSION: The HADS can be used effectively as an initial screening tool for the detection of MDD in outpatients attending mixed cancer clinics.


Asunto(s)
Trastorno Depresivo Mayor/diagnóstico , Tamizaje Masivo , Neoplasias/psicología , Determinación de la Personalidad/estadística & datos numéricos , Adulto , Anciano , Atención Ambulatoria , Estudios Transversales , Trastorno Depresivo Mayor/epidemiología , Trastorno Depresivo Mayor/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psicometría/estadística & datos numéricos , Reproducibilidad de los Resultados , Escocia
13.
Evolution ; 61(3): 708-12; discussion 713-5, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17348934

RESUMEN

How the displays of bowerbirds have evolved has attracted widespread interest. Endler et al. (2005) analyzed color use in display in a subset of bowerbird species and generalized their results to all bowerbirds. Here we discuss problems with their analysis that calls into question their conclusions. For example, they state that bowerbirds do not use decorations that match their background, but this is not supported by their results. They reconstruct historical patterns of sexual dimorphism in plumage display using questionable methodology. The high lability of these display traits makes these reconstructions unreliable and, using accepted methods and acknowledging the lability problem, we were unable to support their conclusions. Their claim that plumage differences between sympatric species are due to character displacement is not supported by the available data. Their focus is on visual contrast as the cause for display color and we offer additional hypotheses that may contribute to explaining color use. We support studies of spectral analysis of display traits but urge greater care in using this information to reach conclusions about how colorful displays have evolved.


Asunto(s)
Comunicación Animal , Evolución Biológica , Color , Passeriformes/fisiología , Animales , Plumas/anatomía & histología , Plumas/fisiología , Femenino , Masculino , Preferencia en el Apareamiento Animal , Passeriformes/anatomía & histología , Caracteres Sexuales , Especificidad de la Especie
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