802 research outputs found
TB8: Enzyme Levels in Birds
This technical bulletin describes a research project relating to enzymes and chickens during health and disease. This project was started in 1957, and with the aid of a National Institutes of Health grant #C-4957 in 1959 the work was accelerated. This bulletin covers some of the work that has not been published and at also summarizes some of the literature relating to enzyme activity levels in birds.https://digitalcommons.library.umaine.edu/aes_techbulletin/1190/thumbnail.jp
Measurement errors in body size of sea scallops (Placopecten magellanicus) and their effect on stock assessment models
Body-size measurement errors are usually ignored in stock
assessments, but may be important when body-size data (e.g., from visual sur veys) are imprecise. We used
experiments and models to quantify measurement errors and their effects on assessment models for sea scallops
(Placopecten magellanicus). Errors in size data obscured modes from strong year classes and increased frequency
and size of the largest and smallest sizes, potentially biasing growth, mortality, and biomass estimates. Modeling
techniques for errors in age data proved useful for errors in size data. In terms of a goodness of model fit to the assessment data, it was more important to accommodate variance than bias. Models that accommodated size errors fitted size data substantially better. We recommend experimental quantification of errors along with a modeling approach that accommodates measurement errors because a direct algebraic approach was not robust and because error parameters were diff icult to estimate in our assessment model. The importance of measurement errors depends on
many factors and should be evaluated on a case by case basis
National Center for Biomedical Ontology: Advancing biomedicine through structured organization of scientific knowledge
The National Center for Biomedical Ontology is a consortium that comprises leading informaticians, biologists, clinicians, and ontologists, funded by the National Institutes of Health (NIH) Roadmap, to develop innovative technology and methods that allow scientists to record, manage, and disseminate biomedical information and knowledge in machine-processable form. The goals of the Center are (1) to help unify the divergent and isolated efforts in ontology development by promoting high quality open-source, standards-based tools to create, manage, and use ontologies, (2) to create new software tools so that scientists can use ontologies to annotate and analyze biomedical data, (3) to provide a national resource for the ongoing evaluation, integration, and evolution of biomedical ontologies and associated
tools and theories in the context of driving biomedical projects (DBPs), and (4) to disseminate the tools and resources of the Center and to identify, evaluate, and communicate best practices of ontology development to the biomedical community. Through the research activities within the Center, collaborations with the DBPs, and interactions with the biomedical community, our goal is to help scientists to work more effectively in the e-science paradigm, enhancing experiment design, experiment execution, data analysis, information synthesis, hypothesis generation and testing, and understand human disease
YPFS Lessons Learned Oral History Project: An Interview with Matthew A. Feldman
Suggested Citation Form: Feldman, Matthew A., 2019. “Lessons Learned Interview. Interview by Mary Anne Chute Lynch and Alexander Nye. Yale Program on Financial Stability Lessons Learned Oral History Project. October 25, 2019. Transcript. https://ypfs.som.yale.edu/library/ypfs-lesson-learned-oral-history-project-interview-matthew-feldma
Analyzing historical diagnosis code data from NIH N3C and RECOVER Programs using deep learning to determine risk factors for Long Covid
Post-acute sequelae of SARS-CoV-2 infection (PASC) or Long COVID is an
emerging medical condition that has been observed in several patients with a
positive diagnosis for COVID-19. Historical Electronic Health Records (EHR)
like diagnosis codes, lab results and clinical notes have been analyzed using
deep learning and have been used to predict future clinical events. In this
paper, we propose an interpretable deep learning approach to analyze historical
diagnosis code data from the National COVID Cohort Collective (N3C) to find the
risk factors contributing to developing Long COVID. Using our deep learning
approach, we are able to predict if a patient is suffering from Long COVID from
a temporally ordered list of diagnosis codes up to 45 days post the first COVID
positive test or diagnosis for each patient, with an accuracy of 70.48\%. We
are then able to examine the trained model using Gradient-weighted Class
Activation Mapping (GradCAM) to give each input diagnoses a score. The highest
scored diagnosis were deemed to be the most important for making the correct
prediction for a patient. We also propose a way to summarize these top
diagnoses for each patient in our cohort and look at their temporal trends to
determine which codes contribute towards a positive Long COVID diagnosis
CheXpert: A Large Chest Radiograph Dataset with Uncertainty Labels and Expert Comparison
Large, labeled datasets have driven deep learning methods to achieve
expert-level performance on a variety of medical imaging tasks. We present
CheXpert, a large dataset that contains 224,316 chest radiographs of 65,240
patients. We design a labeler to automatically detect the presence of 14
observations in radiology reports, capturing uncertainties inherent in
radiograph interpretation. We investigate different approaches to using the
uncertainty labels for training convolutional neural networks that output the
probability of these observations given the available frontal and lateral
radiographs. On a validation set of 200 chest radiographic studies which were
manually annotated by 3 board-certified radiologists, we find that different
uncertainty approaches are useful for different pathologies. We then evaluate
our best model on a test set composed of 500 chest radiographic studies
annotated by a consensus of 5 board-certified radiologists, and compare the
performance of our model to that of 3 additional radiologists in the detection
of 5 selected pathologies. On Cardiomegaly, Edema, and Pleural Effusion, the
model ROC and PR curves lie above all 3 radiologist operating points. We
release the dataset to the public as a standard benchmark to evaluate
performance of chest radiograph interpretation models.
The dataset is freely available at
https://stanfordmlgroup.github.io/competitions/chexpert .Comment: Published in AAAI 201
Association Between COVID-19 and Mortality in Hip Fracture Surgery in the National COVID Cohort Collaborative (N3C): A Retrospective Cohort Study
BACKGROUND: This study investigated the outcomes of coronavirus disease (COVID-19)-positive patients undergoing hip fracture surgery using a national database.
METHODS: This is a retrospective cohort study comparing hip fracture surgery outcomes between COVID-19 positive and negative matched cohorts from 46 sites in the United States. Patients aged 65 and older with hip fracture surgery between March 15 and December 31, 2020, were included. The main outcomes were 30-day all-cause mortality and all-cause mortality.
RESULTS: In this national study that included 3303 adults with hip fracture surgery, the 30-day mortality was 14.6% with COVID-19-positive versus 3.8% in COVID-19-negative, a notable difference. The all-cause mortality for hip fracture surgery was 27.0% in the COVID-19-positive group during the study period.
DICUSSION: We found higher incidence of all-cause mortality in patients with versus without diagnosis of COVID-19 after undergoing hip fracture surgery. The mortality in hip fracture surgery in this national analysis was lower than other local and regional reports. The medical community can use this information to guide the management of hip fracture patients with a diagnosis of COVID-19
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