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1.
Eur Phys J C Part Fields ; 81(4): 337, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720714

RESUMO

The selection of low-radioactive construction materials is of utmost importance for the success of low-energy rare event search experiments. Besides radioactive contaminants in the bulk, the emanation of radioactive radon atoms from material surfaces attains increasing relevance in the effort to further reduce the background of such experiments. In this work, we present the 222 Rn emanation measurements performed for the XENON1T dark matter experiment. Together with the bulk impurity screening campaign, the results enabled us to select the radio-purest construction materials, targeting a 222 Rn activity concentration of 10 µ Bq / kg in 3.2 t of xenon. The knowledge of the distribution of the 222 Rn sources allowed us to selectively eliminate problematic components in the course of the experiment. The predictions from the emanation measurements were compared to data of the 222 Rn activity concentration in XENON1T. The final 222 Rn activity concentration of ( 4.5 ± 0.1 ) µ Bq / kg in the target of XENON1T is the lowest ever achieved in a xenon dark matter experiment.

2.
Phys Rev Lett ; 127(15): 151803, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34678031

RESUMO

We present a search for the decays of a neutral scalar boson produced by kaons decaying at rest, in the context of the Higgs portal model, using the MicroBooNE detector. We analyze data triggered in time with the Fermilab NuMI neutrino beam spill, with an exposure of 1.93×10^{20} protons on target. We look for monoenergetic scalars that come from the direction of the NuMI hadron absorber, at a distance of 100 m from the detector, and decay to electron-positron pairs. We observe one candidate event, with a standard model background prediction of 1.9±0.8. We set an upper limit on the scalar-Higgs mixing angle of θ<(3.3-4.6)×10^{-4} at the 95% confidence level for scalar boson masses in the range (100-200) MeV/c^{2}. We exclude, at the 95% confidence level, the remaining model parameters required to explain the central value of a possible excess of K_{L}^{0}→π^{0}νν[over ¯] decays reported by the KOTO collaboration. We also provide a model-independent limit on a new boson X produced in K→πX decays and decaying to e^{+}e^{-}.

3.
PeerJ ; 9: e12013, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34692243

RESUMO

Background: Globally, amphibian species have suffered drastic population declines over the past 40 years. Hundreds of species are now listed as Critically Endangered, with many of these considered "possibly extinct". Most of these species are stream-dwelling frogs inhabiting remote, montane areas, where remnant populations are hard to find using traditional surveys. Environmental DNA (eDNA) could revolutionize surveys for 'missing' and endangered amphibian populations by screening water samples from downstream sections to assess presence in the upstream catchments. However, the utility of this survey technique is dependent on quantifying downstream detection probability and distances. Methods: Here we tested downstream detection distances in two endangered stream frogs (Litoria lorica and L. nannotis) that co-occur in a remote stream catchment in north-east Australia, and for which we know precise downstream distributional limits from traditional surveys. Importantly, the two last populations of L. lorica persist in this catchment: one small (~1,000 frogs) and one very small (~100 frogs). We conducted eDNA screening at a series of sites kilometers downstream from the populations using precipitation from two fixed water volumes (15 and 100 mL) and via water filtering (mean 1,480 L). Results: We detected L. nannotis and the small L. lorica population (~1,000 frogs) at most sampling sites, including 22.8 km downstream. The filtration method was highly effective for far-downstream detection, as was precipitation from 100 mL water samples, which also resulted in consistent detections at the far-downstream sites (including to 22.8 km). In contrast, we had limited downstream detection success for the very small L. lorica population (~100 frogs). Discussion: The ecological aspects of our study system, coupled with thorough traditional surveys, enabled us to measure downstream eDNA detection distances with accuracy. We demonstrate that eDNA from a small population of approximately 1,000 frogs can be detected as far as 22.8 km downstream from the population. Water filtration is considered best for eDNA detection of rare aquatic species-indeed it was effective in this study-but we also achieved far-downstream detections when precipitating eDNA from 100 mL water samples. Collecting small water volumes for subsequent precipitation in the lab is more practical than filtration when surveying remote areas. Our downstream detection distances (>20 km) suggest eDNA is a valuable tool for detecting rare stream amphibians. We provide recommendations on optimal survey methods.

4.
Int J Surg ; 94: 106133, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34597822

RESUMO

The exponential increase in the volume and complexity of healthcare data presents new challenges to researchers and clinicians in analysis and interpretation. The requirement for new strategies to extract meaningful information from large, noisy datasets has led to the development of the field of big data analytics. Artificial intelligence (AI) is a general-purpose technology in which machines carry out tasks traditionally thought to be only achievable by humans. Machine learning (ML) is an approach to AI in which machines can "learn" to perform tasks in an automated process, rather than being explicitly programmed by a human. Research aiming to apply ML techniques to classification, prediction and decision-making problems in healthcare has increased 61-fold from 2005 to 2019, mirroring this sense of early promise. The field of healthcare ML is relatively young, and many critical steps are needed before adoption into clinical practice, including transparent, unbiased development and reporting of algorithms. Articles claiming that machines can outperform, or replace, doctors in high-level tasks, such as diagnosis or prognostication, must be carefully appraised. It is critical that surgeons have an understanding of the principles and terminology of AI and ML to evaluate these claims and to take an active role in directing research. This article is an up-to-date review and primer for surgeons covering the core tenets of ML applied to surgical problems, including algorithm types and selection, model training and validation, interpretation of common outcome metrics, current and future reporting guidelines and discussion of the challenges and limitations in this field.


Assuntos
Inteligência Artificial , Cirurgiões , Algoritmos , Atenção à Saúde , Humanos , Aprendizado de Máquina
5.
PLoS One ; 16(10): e0257444, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34710099

RESUMO

Floodplains represent critical nursery habitats for a variety of fish species due to their highly productive food webs, yet few tools exist to quantify the extent to which these habitats contribute to ecosystem-level production. Here we conducted a large-scale field experiment to characterize differences in food web composition and stable isotopes (δ¹³C, δ¹5N, δ³4S) for salmon rearing on a large floodplain and adjacent river in the Central Valley, California, USA. The study covered variable hydrologic conditions including flooding (1999, 2017), average (2016), and drought (2012-2015). In addition, we determined incorporation rates and tissue fractionation between prey and muscle from fish held in enclosed locations (experimental fields, cages) at weekly intervals. Finally, we measured δ³4S in otoliths to test if these archival biominerals could be used to reconstruct floodplain use. Floodplain-reared salmon had a different diet composition and lower δ13C and δ³4S (δ¹³C = -33.02±2.66‰, δ³4S = -3.47±2.28‰; mean±1SD) compared to fish in the adjacent river (δ¹³C = -28.37±1.84‰, δ³4S = +2.23±2.25‰). These isotopic differences between habitats persisted across years of extreme droughts and floods. Despite the different diet composition, δ¹5N values from prey items on the floodplain (δ¹5N = 7.19±1.22‰) and river (δ¹5N = 7.25±1.46‰) were similar, suggesting similar trophic levels. The food web differences in δ13C and δ³4S between habitats were also reflected in salmon muscle tissue, reaching equilibrium between 24-30 days (2014, δ¹³C = -30.74±0.73‰, δ³4S = -4.6±0.68‰; 2016, δ¹³C = -34.74 ±0.49‰, δ³4S = -5.18±0.46‰). δ³4S measured in sequential growth bands in otoliths recorded a weekly time-series of shifting diet inputs, with the outermost layers recording time spent on the floodplain (δ³4S = -5.60±0.16‰) and river (δ³4S = 3.73±0.98‰). Our results suggest that δ¹³C and δ³4S can be used to differentiate floodplain and river rearing habitats used by native fishes, such as Chinook Salmon, across different hydrologic conditions and tissues. Together these stable isotope analyses provide a toolset to quantify the role of floodplains as fish habitats.


Assuntos
Salmão/crescimento & desenvolvimento , Fenômenos Fisiológicos da Nutrição Animal , Animais , Isótopos de Carbono/análise , Ecossistema , Cadeia Alimentar , Isótopos de Nitrogênio/análise , Rios , Salmão/fisiologia , Isótopos de Enxofre/análise
7.
Ecol Evol ; 11(17): 11749-11761, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34522338

RESUMO

Australia is in the midst of an extinction crisis, having already lost 10% of terrestrial mammal fauna since European settlement and with hundreds of other species at high risk of extinction. The decline of the nation's biota is a result of an array of threatening processes; however, a comprehensive taxon-specific understanding of threats and their relative impacts remains undocumented nationally. Using expert consultation, we compile the first complete, validated, and consistent taxon-specific threat and impact dataset for all nationally listed threatened taxa in Australia. We confined our analysis to 1,795 terrestrial and aquatic taxa listed as threatened (Vulnerable, Endangered, or Critically Endangered) under Australian Commonwealth law. We engaged taxonomic experts to generate taxon-specific threat and threat impact information to consistently apply the IUCN Threat Classification Scheme and Threat Impact Scoring System, as well as eight broad-level threats and 51 subcategory threats, for all 1,795 threatened terrestrial and aquatic threatened taxa. This compilation produced 4,877 unique taxon-threat-impact combinations with the most frequently listed threats being Habitat loss, fragmentation, and degradation (n = 1,210 taxa), and Invasive species and disease (n = 966 taxa). Yet when only high-impact threats or medium-impact threats are considered, Invasive species and disease become the most prevalent threats. This dataset provides critical information for conservation action planning, national legislation and policy, and prioritizing investments in threatened species management and recovery.

8.
Plast Reconstr Surg Glob Open ; 9(9): e3806, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34549001

RESUMO

Background: The CLEFT-Q is a patient-reported outcome measure with seven scales measuring elements of facial appearance in cleft lip and/or palate. We built on the validated CLEFT-Q structural model to describe conceptual relationships between these scales, and tested our hypothesis through structural equation modeling (SEM). In our hypothesized model, the appearance of the nose, nostrils, teeth, jaw, lips, and cleft lip scar all contribute to overall facial appearance. Methods: We included 640 participants from the international CLEFT-Q field test. Model fit was assessed using weighted least squares mean and variance adjusted regression. The model was then refined through modification indices. The fit of the hypothesized model was confirmed in an independent sample of 452 participants. Results: The refined model demonstrated excellent fit to the data (comparative fit index 0.999, Tucker-Lewis index 0.999, root mean square error of approximation 0.036 and standardized root mean square residual 0.036). The confirmatory analysis also demonstrated excellent model fit. Conclusion: Our structural model, based on a clinical understanding of appearance in orofacial clefting, aligns with CLEFT-Q field test data. This supports the instrument's use and the exploration of a wider range of applications, such as multidimensional computerized adaptive testing.

9.
BMC Med Res Methodol ; 21(1): 158, 2021 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-34332525

RESUMO

BACKGROUND: Unstructured text, including medical records, patient feedback, and social media comments, can be a rich source of data for clinical research. Natural language processing (NLP) describes a set of techniques used to convert passages of written text into interpretable datasets that can be analysed by statistical and machine learning (ML) models. The purpose of this paper is to provide a practical introduction to contemporary techniques for the analysis of text-data, using freely-available software. METHODS: We performed three NLP experiments using publicly-available data obtained from medicine review websites. First, we conducted lexicon-based sentiment analysis on open-text patient reviews of four drugs: Levothyroxine, Viagra, Oseltamivir and Apixaban. Next, we used unsupervised ML (latent Dirichlet allocation, LDA) to identify similar drugs in the dataset, based solely on their reviews. Finally, we developed three supervised ML algorithms to predict whether a drug review was associated with a positive or negative rating. These algorithms were: a regularised logistic regression, a support vector machine (SVM), and an artificial neural network (ANN). We compared the performance of these algorithms in terms of classification accuracy, area under the receiver operating characteristic curve (AUC), sensitivity and specificity. RESULTS: Levothyroxine and Viagra were reviewed with a higher proportion of positive sentiments than Oseltamivir and Apixaban. One of the three LDA clusters clearly represented drugs used to treat mental health problems. A common theme suggested by this cluster was drugs taking weeks or months to work. Another cluster clearly represented drugs used as contraceptives. Supervised machine learning algorithms predicted positive or negative drug ratings with classification accuracies ranging from 0.664, 95% CI [0.608, 0.716] for the regularised regression to 0.720, 95% CI [0.664,0.776] for the SVM. CONCLUSIONS: In this paper, we present a conceptual overview of common techniques used to analyse large volumes of text, and provide reproducible code that can be readily applied to other research studies using open-source software.


Assuntos
Aprendizado de Máquina , Processamento de Linguagem Natural , Algoritmos , Humanos , Redes Neurais de Computação , Máquina de Vetores de Suporte
10.
Compend Contin Educ Dent ; 42(7): 382-388, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34297593

RESUMO

Along with the many technological advancements in implant-supported restorations that have impacted dentistry in recent years has come an evolution in clinical workflows and the dental materials to support them. Today, a synergy is rapidly forming in the dental industry among digital design, processing equipment, and restorative materials. This interaction is leading to increased clinical predictability supported by high-quality products. This review discusses the latest cutting-edge materials used in the restoration of implant-supported cases and how these materials fit into modern-day digital workflows.


Assuntos
Implantes Dentários , Prótese Dentária Fixada por Implante , Materiais Dentários , Planejamento de Prótese Dentária , Estética Dentária , Fluxo de Trabalho
11.
Curr Oncol ; 28(4): 2560-2578, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34287274

RESUMO

Lung metastases are the second most common malignant neoplasms of the lung. It is estimated that 20-54% of cancer patients have lung metastases at some point during their disease course, and at least 50% of cancer-related deaths occur at this stage. Lung metastases are widely accepted to be oligometastatic when five lesions or less occur separately in up to three organs. Stereotactic body radiation therapy (SBRT) is a noninvasive, safe, and effective treatment for metastatic lung disease in carefully selected patients. There is no current consensus on the ideal dose and fractionation for SBRT in lung metastases, and it is the subject of study in ongoing clinical trials, which examines different locations in the lung (central and peripheral). This review discusses current indications, fractionations, challenges, and technical requirements for lung SBRT.


Assuntos
Neoplasias Pulmonares , Radiocirurgia , Progressão da Doença , Fracionamento da Dose de Radiação , Humanos , Resultado do Tratamento
12.
J Med Internet Res ; 23(7): e26412, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34328443

RESUMO

BACKGROUND: Computerized adaptive testing (CAT) has been shown to deliver short, accurate, and personalized versions of the CLEFT-Q patient-reported outcome measure for children and young adults born with a cleft lip and/or palate. Decision trees may integrate clinician-reported data (eg, age, gender, cleft type, and planned treatments) to make these assessments even shorter and more accurate. OBJECTIVE: We aimed to create decision tree models incorporating clinician-reported data into adaptive CLEFT-Q assessments and compare their accuracy to traditional CAT models. METHODS: We used relevant clinician-reported data and patient-reported item responses from the CLEFT-Q field test to train and test decision tree models using recursive partitioning. We compared the prediction accuracy of decision trees to CAT assessments of similar length. Participant scores from the full-length questionnaire were used as ground truth. Accuracy was assessed through Pearson's correlation coefficient of predicted and ground truth scores, mean absolute error, root mean squared error, and a two-tailed Wilcoxon signed-rank test comparing squared error. RESULTS: Decision trees demonstrated poorer accuracy than CAT comparators and generally made data splits based on item responses rather than clinician-reported data. CONCLUSIONS: When predicting CLEFT-Q scores, individual item responses are generally more informative than clinician-reported data. Decision trees that make binary splits are at risk of underfitting polytomous patient-reported outcome measure data and demonstrated poorer performance than CATs in this study.


Assuntos
Fenda Labial , Fissura Palatina , Fenda Labial/diagnóstico , Fissura Palatina/diagnóstico , Humanos , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida
13.
PLoS Biol ; 19(6): e3001210, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34061821

RESUMO

Global biodiversity loss is a profound consequence of human activity. Disturbingly, biodiversity loss is greater than realized because of the unknown number of undocumented species. Conservation fundamentally relies on taxonomic recognition of species, but only a fraction of biodiversity is described. Here, we provide a new quantitative approach for prioritizing rigorous taxonomic research for conservation. We implement this approach in a highly diverse vertebrate group-Australian lizards and snakes. Of 870 species assessed, we identified 282 (32.4%) with taxonomic uncertainty, of which 17.6% likely comprise undescribed species of conservation concern. We identify 24 species in need of immediate taxonomic attention to facilitate conservation. Using a broadly applicable return-on-investment framework, we demonstrate the importance of prioritizing the fundamental work of identifying species before they are lost.


Assuntos
Biodiversidade , Classificação , Pesquisa , Animais , Austrália , Lagartos/classificação , Serpentes/classificação
16.
J Grad Med Educ ; 13(2): 276-280, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33897962

RESUMO

Background: With the recent announcement that Step 1 score reporting will soon change to pass/fail, residency programs will need to reconsider their recruitment processes. Objective: We (1) evaluated the feasibility of blinding residency programs to applicants' Step 1 scores and their number of attempts throughout the recruitment process; (2) described the selection process that resulted from the blinding; and (3) reviewed if a program's initial rank list, created before scores were known, would be changed before submission for the Match. Methods: During the 2018-2019 and 2019-2020 recruitment seasons, all programs at a single sponsoring institution were invited to develop selection criteria in the absence of Step 1 data, and to remain blinded to this data throughout recruitment. Participating programs were surveyed to determine factors affecting feasibility and metrics used for residency selection. Once unblinded to Step 1 scores, programs had the option to change their initial rank lists. Results: Of 24 residency programs, 4 participated (17%) in the first year: emergency medicine, neurology, pediatrics, and psychiatry. The second year had the same participants, with the addition of family and community medicine and radiation oncology (n = 6, 25%). Each program was able to determine mission-specific qualities in the absence of Step 1 data. In both years, one program made changes to the final rank list. Conclusions: It was feasible for programs to establish metrics for residency recruitment in the absence of Step 1 data, and most programs made no changes to final rank lists after Step 1 scores were known.


Assuntos
Medicina de Emergência , Internato e Residência , Criança , Medicina de Emergência/educação , Estudos de Viabilidade , Humanos , Inquéritos e Questionários
17.
Phys Rev Lett ; 126(9): 091301, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33750173

RESUMO

We report on a search for nuclear recoil signals from solar ^{8}B neutrinos elastically scattering off xenon nuclei in XENON1T data, lowering the energy threshold from 2.6 to 1.6 keV. We develop a variety of novel techniques to limit the resulting increase in backgrounds near the threshold. No significant ^{8}B neutrinolike excess is found in an exposure of 0.6 t×y. For the first time, we use the nondetection of solar neutrinos to constrain the light yield from 1-2 keV nuclear recoils in liquid xenon, as well as nonstandard neutrino-quark interactions. Finally, we improve upon world-leading constraints on dark matter-nucleus interactions for dark matter masses between 3 and 11 GeV c^{-2} by as much as an order of magnitude.

18.
J Cosmet Dermatol ; 2021 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-33779023

RESUMO

INTRODUCTION: Safeguarding the integrity of the donor site during the initial suspension phase of an interpolation flap is difficult. There are a variety of approaches and no consensus on post-operative management of the donor site or pedicle following the creation of the flap. The use of xenografts at the donor site of postauricular interpolation flaps simplifies post-operative wound care and prevents infection, desiccation of tissue, reduces pain, and assists with hemostasis. METHODS: A porcine acellular dermal skin substitute can be utilized for the purpose of care-free interpolation flap wound care. First, the flap is designed and raised using standard surgical technique. The porcine xenograft is then sutured into the donor site and to the exposed subcutaneous side of the flap pedicle using nylon suture material. The flap then is interpolated and sutured into the surgical defect of the auricle. Silicone gel is applied to the surface of the xenograft. A pressure dressing is then placed over the surgical site. RESULTS: A total of 4 patients had postauricular interpolation flaps to the ipsilateral helix. All four patients had a xenograft placed at the donor site and flap pedicle at the time of the flap creation and suspension. No infections and no incidence of post-operative bleeding requiring intervention were noted. CONCLUSION: Utilizing a dermal skin substitute as a biological dressing for an interpolation flap prior to division and inset of the flap provides a useful alternative to traditional wound care during this interim period.

19.
J Allergy Clin Immunol ; 148(2): 420-427.e5, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33581200

RESUMO

BACKGROUND: A total of 15 states allow schools to manage respiratory emergencies among multiple students by using a single albuterol inhaler (stock inhaler) paired with a disposable holding chamber. OBJECTIVE: Our aim was to evaluate implementation barriers and facilitators, as well as satisfaction with a stock inhaler program across K through12 schools in Pima County, Arizona. METHODS: All public, charter, private, and parochial schools were offered supplies, web-based training, and technical assistance at no cost. The RE-AIM (Reach, Effectiveness, Adoption, Implementation and Maintenance) framework was used to evaluate program implementation. School documentation logs were reviewed, school health personnel were surveyed, and a convenience sample of health personnel were interviewed. Chi-square tests evaluated categoric outcomes and Poisson hurdle regression examined stock inhaler use by school organization type, grade levels served, and type of school health personnel employed. RESULTS: In all, 229 schools (68%) participated, reaching 82% of students in the county. A total of 152 schools (66%) used a stock inhaler, accounting for 1038 events. The mean number of puffs administered was 2.7 (SD = 1.2) per event, and most events (79%) involved students with asthma. Although most events (83.9%) resulted in the student returning to class, 15.6% resulted in students being sent home. Only 6 events resulted in 911 calls, and 5 of these led to an ambulance transport. School health personnel reported high levels of satisfaction, and all schools renewed participation for a second year. Program costs were $156 per school. CONCLUSION: With technical assistance, stock inhaler programs can be feasibly implemented by schools in a wide range of settings, thereby increasing their capacity to safely manage respiratory emergencies.


Assuntos
Albuterol/administração & dosagem , Asma/tratamento farmacológico , Serviços de Saúde Escolar , Instituições Acadêmicas , Administração por Inalação , Adolescente , Arizona/epidemiologia , Asma/epidemiologia , Criança , Emergências , Feminino , Humanos , Masculino
20.
Ecol Appl ; 31(2): e02243, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33098718

RESUMO

Many estuarine ecosystems and the fish communities that inhabit them have undergone substantial changes in the past several decades, largely due to multiple interacting stressors that are often of anthropogenic origin. Few are more impactful than droughts, which are predicted to increase in both frequency and severity with climate change. In this study, we examined over five decades of fish monitoring data from the San Francisco Estuary, California, USA, to evaluate the resistance and resilience of fish communities to disturbance from prolonged drought events. High resistance was defined by the lack of decline in species occurrence from a wet to a subsequent drought period, while high resilience was defined by the increase in species occurrence from a drought to a subsequent wet period. We found some unifying themes connecting the multiple drought events over the 50-yr period. Pelagic fishes consistently declined during droughts (low resistance), but exhibit a considerable amount of resiliency and often rebound in the subsequent wet years. However, full recovery does not occur in all wet years following droughts, leading to permanently lower baseline numbers for some pelagic fishes over time. In contrast, littoral fishes seem to be more resistant to drought and may even increase in occurrence during dry years. Based on the consistent detrimental effects of drought on pelagic fishes within the San Francisco Estuary and the inability of these fish populations to recover in some years, we conclude that freshwater flow remains a crucial but not sufficient management tool for the conservation of estuarine biodiversity.


Assuntos
Secas , Estuários , Animais , Ecossistema , Peixes , São Francisco
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