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1.
Transl Anim Sci ; 8: txae076, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38764467

RESUMO

Waterfowl are housed in captivity for research studies that are infeasible in the wild. Accommodating the unique requirements of semi-aquatic species in captivity while meeting experimental design criteria for research questions can be challenging and may have unknown effects on animal health. Thus, testing and standardizing best husbandry and care practices for waterfowl is necessary to facilitate proper husbandry and humane care while ensuring reliable and repeatable research results. To inform husbandry practices for captive-reared and wild-caught lesser scaup (Aythya affinis; hereafter, scaup), we assessed body mass and fat composition across two different aspects of husbandry, source population (captive-reared or wild caught), and housing densities (birds/m2). Our results suggest that housing scaup at low densities (≤0.6 m2/bird, P = 0.049) relative to other species can minimize negative health effects. Captive-reared scaup were heavier (P = 0.027) with greater body fat (P < 0.001) and exhibited fewer signs of stress during handling than wild-caught scaup. In our experience, scaup which are captive-reared from eggs collected in the wild were better for long-term captivity studies as they maintained body mass between and recovered lost body mass following trials. Researchers would benefit from carefully evaluating the tradeoffs of using short- and long-term captive methods on their research question before designing projects, husbandry practices, and housing facilities for waterfowl.

3.
Ecol Appl ; 34(3): e2952, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38417451

RESUMO

Animals balance costs of antipredator behaviors with resource acquisition to minimize hunting and other mortality risks and maximize their physiological condition. This inherent trade-off between forage abundance, its quality, and mortality risk is intensified in human-dominated landscapes because fragmentation, habitat loss, and degradation of natural vegetation communities is often coupled with artificially enhanced vegetation (i.e., food plots), creating high-risk, high-reward resource selection decisions. Our goal was to evaluate autumn-winter resource selection trade-offs for an intensively hunted avian generalist. We hypothesized human access was a reliable cue for hunting predation risk. Therefore, we predicted resource selection patterns would be spatiotemporally dependent upon levels of access and associated perceived risk. Specifically, we evaluated resource selection of local-scale flights between diel periods for 426 mallards (Anas platyrhynchos) relative to wetland type, forage quality, and differing levels of human access across hunting and nonhunting seasons. Mallards selected areas that prohibited human access and generally avoided areas that allowed access diurnally, especially during the hunting season. Mallards compensated by selecting for high-energy and greater quality foraging patches on allowable human access areas nocturnally when they were devoid of hunters. Postseason selection across human access gradients did not return to prehunting levels immediately, perhaps suggesting a delayed response to reacclimate to nonhunted activities and thus agreeing with the assessment mismatch hypothesis. Last, wetland availability and human access constrained selection for optimal natural forage quality (i.e., seed biomass and forage productivity) diurnally during preseason and hunting season, respectively; however, mallards were freed from these constraints nocturnally during hunting season and postseason periods. Our results suggest risk-avoidance of human accessible (i.e., hunted) areas is a primary driver of resource selection behaviors by mallards and could be a local to landscape-level process influencing distributions, instead of forage abundance and quality, which has long-been assumed by waterfowl conservation planners in North America. Broadly, even an avian generalist, well adapted to anthropogenic landscapes, avoids areas where hunting and human access are allowed. Future conservation planning and implementation must consider management for recreational access (i.e., people) equally important as foraging habitat management for wintering waterfowl.


Assuntos
Patos , Ecossistema , Animais , Humanos , Biomassa , Patos/fisiologia , Áreas Alagadas , Comportamento Predatório
4.
Neuroimage ; 286: 120505, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38224825

RESUMO

Functional MRI has emerged as a powerful tool to assess the severity of Post-concussion syndrome (PCS) and to provide guidance for neuro-cognitive therapists during treatment. The next-generation functional neuro-cognitive imaging protocol (fNCI2) has been developed to provide this assessment. This paper covers the first step in the analysis process, the development of a rapidly re-trainable, machine-learning, brain parcellation tool. The use of a sufficiently deep U-Net architecture encompassing a small (39 × 39 × 39 voxel input, 27 × 27 × 27 voxel output) sliding window to sample the entirety of the 3D image allows for the prediction of the entire image using only a single trained network. A large number of training, validating, and testing windows are thus generated from the 101 manually-labeled Mindboggle images, and full-image prediction is provided via a voxel-vote method using overlapping windows. Our method produces parcellated images that are highly consistent with standard atlas-based methods in under 3 min on a modern GPU, and the single network architecture allows for rapid retraining (<36 hr) as needed.


Assuntos
Encéfalo , Redes Neurais de Computação , Humanos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Cognição , Processamento de Imagem Assistida por Computador/métodos
5.
Phys Rev Lett ; 131(22): 221801, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101357

RESUMO

Using an 185-kg NaI[Tl] array, COHERENT has measured the inclusive electron-neutrino charged-current cross section on ^{127}I with pion decay-at-rest neutrinos produced by the Spallation Neutron Source at Oak Ridge National Laboratory. Iodine is one the heaviest targets for which low-energy (≤50 MeV) inelastic neutrino-nucleus processes have been measured, and this is the first measurement of its inclusive cross section. After a five-year detector exposure, COHERENT reports a flux-averaged cross section for electron neutrinos of 9.2_{-1.8}^{+2.1}×10^{-40} cm^{2}. This corresponds to a value that is ∼41% lower than predicted using the MARLEY event generator with a measured Gamow-Teller strength distribution. In addition, the observed visible spectrum from charged-current scattering on ^{127}I has been measured between 10 and 55 MeV, and the exclusive zero-neutron and one-or-more-neutron emission cross sections are measured to be 5.2_{-3.1}^{+3.4}×10^{-40} and 2.2_{-0.5}^{+0.4}×10^{-40} cm^{2}, respectively.

6.
Sci Rep ; 13(1): 14473, 2023 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-37660131

RESUMO

Avian influenza viruses pose a threat to wildlife and livestock health. The emergence of highly pathogenic avian influenza (HPAI) in wild birds and poultry in North America in late 2021 was the first such outbreak since 2015 and the largest outbreak in North America to date. Despite its prominence and economic impacts, we know relatively little about how HPAI spreads in wild bird populations. In January 2022, we captured 43 mallards (Anas platyrhynchos) in Tennessee, USA, 11 of which were actively infected with HPAI. These were the first confirmed detections of HPAI H5N1 clade 2.3.4.4b in the Mississippi Flyway. We compared movement patterns of infected and uninfected birds and found no clear differences; infected birds moved just as much during winter, migrated slightly earlier, and migrated similar distances as uninfected birds. Infected mallards also contacted and shared space with uninfected birds while on their wintering grounds, suggesting ongoing transmission of the virus. We found no differences in body condition or survival rates between infected and uninfected birds. Together, these results show that HPAI H5N1 clade 2.3.4.4b infection was unrelated to body condition or movement behavior in mallards infected at this location during winter; if these results are confirmed in other seasons and as HPAI H5N1 continues to evolve, they suggest that these birds could contribute to the maintenance and dispersal of HPAI in North America. Further research on more species across larger geographic areas and multiple seasons would help clarify potential impacts of HPAI on waterfowl and how this emerging disease spreads at continental scales, across species, and potentially between wildlife and domestic animals.


Assuntos
Virus da Influenza A Subtipo H5N1 , Influenza Aviária , Animais , Influenza Aviária/epidemiologia , Estações do Ano , Patos , Animais Selvagens , América do Norte/epidemiologia
7.
Allergy ; 78(10): 2756-2766, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37366581

RESUMO

BACKGROUND: A modified grass allergen subcutaneous immunotherapy (SCIT) product with MicroCrystalline Tyrosine and monophosphoryl lipid-A as an adjuvant system (Grass MATA MPL [PQ Grass]) is being developed as short-course treatment of grass-pollen allergic rhinitis (SAR) and/or rhinoconjunctivitis. We sought to evaluate the combined symptom and medication score (CSMS) of the optimized cumulative dose of 27,600 standardized units (SU) PQ Grass in a field setting prior to embarking on a pivotal Phase III trial. METHODS: In this exploratory, randomized, double-blind, placebo-controlled trial subjects were enrolled across 14 sites (Germany and the United States of America). Six pre-seasonal subcutaneous injections of PQ Grass (using conventional or extended regimens) or placebo were administered to 119 subjects (aged 18-65 years) with moderate-to-severe SAR with or without asthma that was well-controlled. The primary efficacy endpoint was CSMS during peak grass pollen season (GPS). Secondary endpoints included Rhinoconjunctivitis Quality of Life Questionnaire standardized (RQLQ-S) and allergen-specific IgG4 response. RESULTS: The mean CSMS compared to placebo was 33.1% (p = .0325) and 39.5% (p = .0112) for the conventional and extended regimens, respectively. An increase in IgG4 was shown for both regimens (p < .01) as well as an improvement in total RQLQ-S for the extended regimen (mean change -0.72, p = .02). Both regimens were well-tolerated. CONCLUSIONS: This trial demonstrated a clinically relevant and statistically significant efficacy response to PQ Grass. Unprecedented effect sizes were reached for grass allergy of up to ≈40% compared to placebo for CSMS after only six PQ Grass injections. Both PQ Grass regimens were considered equally safe and well-tolerated. Based on enhanced efficacy profile extended regime will be progressed to the pivotal Phase III trial.

8.
Phys Rev Lett ; 130(5): 051803, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36800477

RESUMO

The COHERENT Collaboration searched for scalar dark matter particles produced at the Spallation Neutron Source with masses between 1 and 220 MeV/c^{2} using a CsI[Na] scintillation detector sensitive to nuclear recoils above 9 keV_{nr}. No evidence for dark matter is found and we thus place limits on allowed parameter space. With this low-threshold detector, we are sensitive to coherent elastic scattering between dark matter and nuclei. The cross section for this process is orders of magnitude higher than for other processes historically used for accelerator-based direct-detection searches so that our small, 14.6 kg detector significantly improves on past constraints. At peak sensitivity, we reject the flux consistent with the cosmologically observed dark-matter concentration for all coupling constants α_{D}<0.64, assuming a scalar dark-matter particle. We also calculate the sensitivity of future COHERENT detectors to dark-matter signals which will ambitiously test multiple dark-matter spin scenarios.

9.
Phys Rev Lett ; 129(8): 081801, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36053683

RESUMO

We measured the cross section of coherent elastic neutrino-nucleus scattering (CEvNS) using a CsI[Na] scintillating crystal in a high flux of neutrinos produced at the Spallation Neutron Source at Oak Ridge National Laboratory. New data collected before detector decommissioning have more than doubled the dataset since the first observation of CEvNS, achieved with this detector. Systematic uncertainties have also been reduced with an updated quenching model, allowing for improved precision. With these analysis improvements, the COHERENT Collaboration determined the cross section to be (165_{-25}^{+30})×10^{-40} cm^{2}, consistent with the standard model, giving the most precise measurement of CEvNS yet. The timing structure of the neutrino beam has been exploited to compare the CEvNS cross section from scattering of different neutrino flavors. This result places leading constraints on neutrino nonstandard interactions while testing lepton flavor universality and measures the weak mixing angle as sin^{2}θ_{W}=0.220_{-0.026}^{+0.028} at Q^{2}≈(50 MeV)^{2}.

10.
Exerc Sport Sci Rev ; 50(4): 231, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36095075
11.
Glob Chang Biol ; 28(18): 5469-5479, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35656733

RESUMO

Global climate change is increasing the frequency and severity of extreme climatic events (ECEs) which may be especially detrimental during late-winter when many species are surviving on scarce resources. However, monitoring animal populations relative to ECEs is logistically challenging. Crowd-sourced datasets may provide opportunity to monitor species' responses to short-term chance phenomena such as ECEs. We used 14 years of eBird-a global citizen science initiative-to examine distribution changes for seven wintering waterfowl species across North America in response to recent extreme winter polar vortex disruptions. To validate inferences from eBird, we compared eBird distribution changes against locational data from 362 GPS-tagged Mallards (Anas platyrhynchos) in the Mississippi Flyway. Distributional shifts between eBird and GPS-tagged Mallards were similar following an ECE in February 2021. In general, the ECE affected continental waterfowl population distributions; however, responses were variable across species and flyways. Waterfowl distributions tended to stay near wintering latitudes or moved north at lesser distances compared with non-ECE years, suggesting preparedness for spring migration was a stronger "pull" than extreme weather was a "push" pressure. Surprisingly, larger-bodied waterfowl with grubbing foraging strategies (i.e., geese) delayed their northward range shift during ECE years, whereas smaller-bodied ducks were less affected. Lastly, wetland obligate species shifted southward during ECE years. Collectively, these results suggest specialized foraging strategies likely related to resource limitations, but not body size, necessitate movement from extreme late-winter weather in waterfowl. Our results demonstrate eBird's potential to monitor population-level effects of weather events, especially severe ECEs. eBird and other crowd-sourced datasets can be valuable to identify species which are adaptable or vulnerable to ECEs and thus, begin to inform conservation policy and management to combat negative effects of global climate change.


Assuntos
Ciência do Cidadão , Clima Extremo , Animais , Mudança Climática , Patos/fisiologia , Estações do Ano , Tempo (Meteorologia)
12.
J Investig Allergol Clin Immunol ; 32(5): 345-356, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-35522054

RESUMO

The prevalence of allergic disorders has increased drastically over the last 50 years to the extent that they can be considered epidemic. At present, allergen-specific immunotherapy (AIT) is the only therapy that targets the underlying cause of allergic disorders, and evidence of its superiority is based on data accumulated from clinical trials and observational studies demonstrating efficacy and safety. However, several aspects remain unresolved, such as harmonization and standardization of manufacturing and quantification procedures across manufacturers, homogeneous reporting of strength, and the establishment of international reference standards for many allergens. This article discusses issues related to the measurement of major allergen content in AIT extracts, raising the question of whether comparison of products from different manufacturers is an appropriate basis for selecting a specific AIT product. Allergen standardization in immunotherapy products is critical for ensuring quality and, thereby, safety and efficacy. However, lack of harmonization in manufacturing processes, allergen quantification (methodologies and references), national regulatory differences, clinical practice, and labeling shows that the comparison of AIT products based solely on major allergen amounts is not rational and, in fact, impossible. Moreover, when rating the information given for a specific product, it is necessary to take into account further inherent characteristics of products and their application in clinical practice, such as the state of extract modification, addition of adjuvant or adjuvant system, route of administration (sublingual/ subcutaneous), and cumulative dose as per posology (including the volume per administration). Finally, only convincing clinical data can serve as the basis for product-specific evaluation and cross-product comparability of individual products.


Assuntos
Alérgenos , Hipersensibilidade , Adjuvantes Imunológicos/uso terapêutico , Dessensibilização Imunológica/métodos , Humanos , Hipersensibilidade/tratamento farmacológico , Prevalência
13.
Exerc Sport Sci Rev ; 50(2): 81-88, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35025844

RESUMO

Prolonged sitting prevents a 1-h bout of running from improving fat oxidation and reducing plasma triglycerides. This "exercise resistance" can be prevented by taking 8500 steps·d-1 or by interrupting 8 h of sitting with hourly cycle sprints. We hypothesize that there is an interplay between background physical activity (e.g., steps·d-1) and the exercise stimuli in regulating some acute and chronic adaptations to exercise.


Assuntos
Período Pós-Prandial , Corrida , Exercício Físico/fisiologia , Humanos , Período Pós-Prandial/fisiologia , Comportamento Sedentário , Triglicerídeos/metabolismo
14.
J Youth Adolesc ; 51(1): 128-140, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34550495

RESUMO

Despite increasing efforts to better understand sexual and gender minority youth (SGMY), asexual youth remain understudied. This study examines differences in health, family support, and school safety among asexual youth (n = 938) from a national study of SGMY (N = 17,112) ages 13-17. Compared to non-asexual youth, asexual youth were more likely to identify as transgender and report a disability, and less likely to identify as Black or Hispanic/Latino. Transgender (versus cisgender) asexual youth fared worse on most study outcomes. Cisgender asexual (versus cisgender non-asexual) youth fared worse on all study outcomes. Transgender asexual (versus transgender non-asexual) youth reported lower sexuality-related family support. These findings underscore the role of gender identity in understanding the experiences of asexual youth.


Assuntos
Minorias Sexuais e de Gênero , Pessoas Transgênero , Adolescente , Feminino , Identidade de Gênero , Humanos , Masculino , Instituições Acadêmicas , Comportamento Sexual
15.
J. investig. allergol. clin. immunol ; 32(5): 345-356, 2022. ilus
Artigo em Inglês | IBECS | ID: ibc-212730

RESUMO

The prevalence of allergic disorders has increased drastically over the last 50 years to the extent that they can be considered epidemic.At present, allergen-specific immunotherapy (AIT) is the only therapy that targets the underlying cause of allergic disorders, and evidenceof its superiority is based on data accumulated from clinical trials and observational studies demonstrating efficacy and safety. However,several aspects remain unresolved, such as harmonization and standardization of manufacturing and quantification procedures acrossmanufacturers, homogeneous reporting of strength, and the establishment of international reference standards for many allergens. Thisarticle discusses issues related to the measurement of major allergen content in AIT extracts, raising the question of whether comparison ofproducts from different manufacturers is an appropriate basis for selecting a specific AIT product. Allergen standardization in immunotherapyproducts is critical for ensuring quality and, thereby, safety and efficacy. However, lack of harmonization in manufacturing processes,allergen quantification (methodologies and references), national regulatory differences, clinical practice, and labeling shows that thecomparison of AIT products based solely on major allergen amounts is not rational and, in fact, impossible. Moreover, when rating theinformation given for a specific product, it is necessary to take into account further inherent characteristics of products and their applicationin clinical practice, such as the state of extract modification, addition of adjuvant or adjuvant system, route of administration (sublingual/subcutaneous), and cumulative dose as per posology (including the volume per administration). Finally, only convincing clinical data canserve as the basis for product-specific evaluation and cross-product comparability of individual products. (AU)


La prevalencia de las enfermedades alérgicas se ha incrementado drásticamente en los últimos 50 años y hoy pueden considerarse unaepidemia. Actualmente, la inmunoterapia específica con alérgenos (ITA) es el único tratamiento dirigido a la causa subyacente de lasenfermedades alérgicas y su superioridad se basa en resultados de ensayos clínicos/estudios observacionales que demuestran su eficaciay seguridad. Pero quedan aspectos sin resolver, como la armonización y estandarización de los procesos de fabricación y cuantificaciónentre fabricantes, la declaración homogénea de la potencia y el establecimiento de estándares internacionales de referencia. En este artículo se discuten aspectos relacionados con la medida del contenido de alérgenos mayores en los extractos de ITA, cuestionandosi, como base para elegir entre productos, es apropiada la comparación entre diferentes fabricantes. La estandarización alergénica escrucial para asegurar la calidad y, por tanto, la seguridad y eficacia de la ITA. Sin embargo, la falta de armonización en los procesos defabricación, la cuantificación alergénica, las diferencias regulatorias, la práctica clínica y el etiquetado, demuestran que comparar productosbasándose únicamente en la cantidad de alérgeno mayor no está justificado y es imposible. Además, cuando se evalúa la informaciónpara un determinado producto, deben tenerse en cuenta las características propias de cada producto y su uso clínico, como el estado dela modificación del extracto, la adición de adyuvantes, la vía de administración y la dosis acumulada. Solo datos clínicos convincentesdeben servir para la evaluación específica de cada producto o como base para la comparación entre productos. (AU)


Assuntos
Humanos , Alérgenos/imunologia , Dessensibilização Imunológica/métodos , Adjuvantes Imunológicos/uso terapêutico , Hipersensibilidade/tratamento farmacológico
16.
Med Sci Sports Exerc ; 53(9): 1937-1944, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34398061

RESUMO

PURPOSE: This study determined if the level of background physical inactivity (steps per day) influences the acute and short-term adaptations to intense aerobic training. METHODS: Sixteen untrained participants (23.6 ± 1.7 yr) completed intense (80%-90% V˙O2peak) short-term training (5 bouts of exercise over 9 d) while taking either 4767 ± 377 steps per day (n = 8; low step) or 16,048 ± 725 steps per day (n = 8; high step). At baseline and after 1 d of acute exercise and then after the short-term training (posttraining), resting metabolic responses to a high-fat meal (i.e., plasma triglyceride concentration and fat oxidation) were assessed during a 6-h high-fat tolerance test. In addition, responses during submaximal exercise were recorded both before and after training during 15 min of cycling (~79% of pretraining V˙O2peak). RESULTS: High step displayed a reduced incremental area under the curve for postprandial plasma triglyceride concentrations by 31% after acute exercise and by 27% after short-term training compared with baseline (P < 0.05). This was accompanied by increased whole-body fat oxidation (24% and 19%; P < 0.05). Furthermore, stress during submaximal exercise as reflected by heart rate, blood lactate, and deoxygenated hemoglobin were all reduced in high step (P < 0.05), indicating classic training responses. Despite completing the same training regimen, low step showed no significant improvements in postprandial fat metabolism or any markers of stress during submaximal exercise after training (P > 0.05). However, the two groups showed a similar 7% increase in V˙O2peak (P < 0.05). CONCLUSION: When completing an intense short-term exercise training program, decreasing daily background steps from 16,000 to approximately 5000 steps per day blunts some of the classic cardiometabolic adaptations to training. The blunting might be more pronounced regarding metabolic factors (i.e., fat oxidation and blood lactate concentration) compared with cardiovascular factors (i.e., V˙O2peak).


Assuntos
Tecido Adiposo/metabolismo , Glicemia/metabolismo , Exercício Físico/fisiologia , Consumo de Oxigênio/fisiologia , Triglicerídeos/sangue , Adulto , Dieta Hiperlipídica , Feminino , Voluntários Saudáveis , Humanos , Masculino , Período Pós-Prandial , Comportamento Sedentário , Adulto Jovem
17.
Eur J Appl Physiol ; 121(8): 2295-2304, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33974126

RESUMO

PURPOSE: Interval exercise allows very high-power outputs to be maintained, a key for stimulating training adaptations. The main purpose of this study was to develop a sprint interval protocol that stimulated both anaerobic and aerobic systems while maximizing power output and minimizing fatigue. The secondary goal was to investigate the influence of inter-sprint recovery duration. METHODS: Sixteen (8 females) participants (age: 23.5 ± 3.4 years, peak oxygen consumption (VO2peak): 45.6 ± 9.2 ml kg-1 min-1) took part in this study. The exercise protocol involved 30 bouts of 4 s maximal cycling sprints using an 'Inertial Load Ergometer'. Recovery durations between sprints of 15, 30 and 45 s were studied in three trials. RESULTS: Peak power output (PPO) was maintained while taking 45 and 30 s of recovery, although it was 9% higher (p < 0.05) during 45 vs. 30 s. PPO with 15 s recovery declined 18% (p < 0.05) and then stabilized as did oxygen consumption (72±2% VO2peak) at a level that might reflect the peak rate of ATP-PC resynthesis from oxidative metabolism. The 15-, 30-, and 45 s trials elicited 72, 56, and 49% VO2peak and 86, 80, and 75% of maximal heart rate (all p<0.001). Perceived exertion increased with shorter recovery periods but remained at 12.6-14.7 and never became 'very hard'. CONCLUSION: The present study describes the use of an inertial-load ergometer to accommodate repeated 4 s maximal cycling sprints that elicit 72% VO2peak when the recovery period is 15 s. However, a recovery duration of 15 s was insufficient for the maintenance of power generation. TRIAL REGISTRATION NUMBER AND DATE: NCT04448925, 26 Jun 2020; retrospectively registered to clinicaltrials.gov.


Assuntos
Adaptação Fisiológica/fisiologia , Ciclismo/fisiologia , Esforço Físico/fisiologia , Aceleração , Estudos Cross-Over , Feminino , Frequência Cardíaca/fisiologia , Humanos , Lactatos/sangue , Masculino , Consumo de Oxigênio/fisiologia , Troca Gasosa Pulmonar/fisiologia , Adulto Jovem
18.
Phys Rev Lett ; 126(1): 012002, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33480779

RESUMO

We report the first measurement of coherent elastic neutrino-nucleus scattering (CEvNS) on argon using a liquid argon detector at the Oak Ridge National Laboratory Spallation Neutron Source. Two independent analyses prefer CEvNS over the background-only null hypothesis with greater than 3σ significance. The measured cross section, averaged over the incident neutrino flux, is (2.2±0.7)×10^{-39} cm^{2}-consistent with the standard model prediction. The neutron-number dependence of this result, together with that from our previous measurement on CsI, confirms the existence of the CEvNS process and provides improved constraints on nonstandard neutrino interactions.

19.
Skin Health Dis ; 1(2): e19, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35664971

RESUMO

Background: Many classifiers have been developed that can distinguish different types of skin lesions (e.g., benign nevi, melanoma) with varying degrees of success.1-5 However, even successfully trained classifiers may perform poorly on images that include artefacts. While problems created by hair and ink markings have been published, quantitative measurements of blur, colour and lighting variations on classification accuracy has not yet been reported to our knowledge. Objectives: We created a system that measures the impact of various artefacts on machine learning accuracy. Our objectives were to (1) quantitatively identify the most egregious artefacts and (2) demonstrate how to assess a classification algorithm's accuracy when input images include artefacts. Methods: We injected artefacts into dermatologic images using techniques that could be controlled with a single variable. This allows us to quantitatively evaluate the impact on the accuracy. We trained two convolutional neural networks on two different binary classification tasks and measured the impact on dermoscopy images over a range of parameter values. The area under the curve and specificity-at-a-given-sensitivity values were measured for each artefact induced at each parameter. Results: General blur had the strongest negative effect on the melanoma versus other task. Conversely, shifting the hue towards blue had a more pronounced effect on the suspicious versus follow task. Conclusions: Classifiers should either mitigate artefacts or detect them. Images should be excluded from diagnosis/recommendation when artefacts are present in amounts outside the machine perceived quality range. Failure to do so will reduce accuracy and impede approval from regulatory agencies.

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