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1.
Pancreas ; 50(7): 916-922, 2021 08 01.
Article in English | MEDLINE | ID: mdl-34629446

ABSTRACT

ABSTRACT: The potential of artificial intelligence (AI) applied to clinical data from electronic health records (EHRs) to improve early detection for pancreatic and other cancers remains underexplored. The Kenner Family Research Fund, in collaboration with the Cancer Biomarker Research Group at the National Cancer Institute, organized the workshop entitled: "Early Detection of Pancreatic Cancer: Opportunities and Challenges in Utilizing Electronic Health Records (EHR)" in March 2021. The workshop included a select group of panelists with expertise in pancreatic cancer, EHR data mining, and AI-based modeling. This review article reflects the findings from the workshop and assesses the feasibility of AI-based data extraction and modeling applied to EHRs. It highlights the increasing role of data sharing networks and common data models in improving the secondary use of EHR data. Current efforts using EHR data for AI-based modeling to enhance early detection of pancreatic cancer show promise. Specific challenges (biology, limited data, standards, compatibility, legal, quality, AI chasm, incentives) are identified, with mitigation strategies summarized and next steps identified.


Subject(s)
Artificial Intelligence , Congresses as Topic , Early Detection of Cancer/methods , Electronic Health Records/statistics & numerical data , Pancreatic Neoplasms/diagnosis , Biomedical Research/methods , Biomedical Research/statistics & numerical data , Humans , Information Dissemination/methods
2.
Pancreas ; 50(3): 251-279, 2021 03 01.
Article in English | MEDLINE | ID: mdl-33835956

ABSTRACT

ABSTRACT: Despite considerable research efforts, pancreatic cancer is associated with a dire prognosis and a 5-year survival rate of only 10%. Early symptoms of the disease are mostly nonspecific. The premise of improved survival through early detection is that more individuals will benefit from potentially curative treatment. Artificial intelligence (AI) methodology has emerged as a successful tool for risk stratification and identification in general health care. In response to the maturity of AI, Kenner Family Research Fund conducted the 2020 AI and Early Detection of Pancreatic Cancer Virtual Summit (www.pdac-virtualsummit.org) in conjunction with the American Pancreatic Association, with a focus on the potential of AI to advance early detection efforts in this disease. This comprehensive presummit article was prepared based on information provided by each of the interdisciplinary participants on one of the 5 following topics: Progress, Problems, and Prospects for Early Detection; AI and Machine Learning; AI and Pancreatic Cancer-Current Efforts; Collaborative Opportunities; and Moving Forward-Reflections from Government, Industry, and Advocacy. The outcome from the robust Summit conversations, to be presented in a future white paper, indicate that significant progress must be the result of strategic collaboration among investigators and institutions from multidisciplinary backgrounds, supported by committed funders.


Subject(s)
Artificial Intelligence , Biomarkers, Tumor/genetics , Carcinoma, Pancreatic Ductal/genetics , Early Detection of Cancer/methods , Genomics/methods , Pancreatic Neoplasms/genetics , Carcinoma, Pancreatic Ductal/diagnosis , Carcinoma, Pancreatic Ductal/therapy , Humans , Interdisciplinary Communication , Pancreatic Neoplasms/diagnosis , Pancreatic Neoplasms/therapy , Prognosis , Survival Analysis
3.
World J Orthop ; 4(4): 267-78, 2013.
Article in English | MEDLINE | ID: mdl-24147262

ABSTRACT

AIM: To determine if rabbit models can be used to quantify the mechanical behaviour involved in tibial stress fracture (TSF) development. METHODS: Fresh rabbit tibiae were loaded under compression using a specifically-designed test apparatus. Weights were incrementally added up to a load of 30 kg and the mechanical behaviour of the tibia was analysed using tests for buckling, bone strain and hysteresis. Structural mechanics equations were subsequently employed to verify that the results were within the range of values predicted by theory. A finite element (FE) model was developed using cross-sectional computer tomography (CT) images scanned from one of the rabbit bones, and a static load of 6 kg (1.5 times the rabbit's body weight) was applied to represent running. The model was validated using the experimental strain gauge data, then geometric and elemental convergence tests were performed in order to find the minimum number of cross-sectional scans and elements respectively required for convergence. The analysis was then performed using both the model and the experimental results to investigate the mechanical behaviour of the rabbit tibia under compressive load and to examine crack initiation. RESULTS: The experimental tests showed that under a compressive load of up to 12 kg, the rabbit tibia demonstrates linear behaviour with little hysteresis. Up to 30 kg, the bone does not fail by elastic buckling; however, there are low levels of tensile stress which predominately occur at and adjacent to the anterior border of the tibial midshaft: this suggests that fatigue failure occurs in these regions, since bone under cyclic loading initially fails in tension. The FE model predictions were consistent with both mechanics theory and the strain gauge results. The model was highly sensitive to small changes in the position of the applied load due to the high slenderness ratio of the rabbit's tibia. The modelling technique used in the current study could have applications in the development of human FE models of bone, where, unlike rabbit tibia, the model would be relatively insensitive to very small changes in load position. However, the rabbit model itself is less beneficial as a tool to understand the mechanical behaviour of TSFs in humans due to the small size of the rabbit bone and the limitations of human-scale CT scanning equipment. CONCLUSION: The current modelling technique could be used to develop human FE models. However, the rabbit model itself has significant limitations in understanding human TSF mechanics.

4.
J Dent Educ ; 74(9): 931-40, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20837734

ABSTRACT

Technical skills are critical for dentists. Computer-based simulation offers a range of potential benefits for surgical training, but to date the development of simulators has not been characterized by a structured investigation of specific mechanisms by which trainees attain competence. This two-part study contributes to the understanding of the manner in which surgical psychomotor skills are acquired so that this knowledge can be incorporated into the design of training simulations. We studied participant groups of varying skill levels as they performed a drilling task in oral surgery. In this first part of our study, we investigated the elements of surgical technique and differences in the drilling performance of novice, competent, and expert dentists. Our results indicate that novice dentists employ a technique that differs considerably in drilling stroke length and duration from that employed by experts. Expert dentists perform faster, apply more force, lift the bur off the bone less, and produce superior results compared with novices.


Subject(s)
Bone and Bones/surgery , Clinical Competence , Education, Dental , Surgery, Oral/education , Bone and Bones/anatomy & histology , Computer Simulation , Cues , Curriculum , Dentists , Humans , Jaw/anatomy & histology , Motor Skills/physiology , Orthognathic Surgical Procedures , Osteotomy/instrumentation , Psychomotor Performance/physiology , Stress, Mechanical , Students, Dental , Time Factors , Tooth/anatomy & histology , Treatment Outcome , User-Computer Interface , Video Recording
5.
Am J Sports Med ; 36(6): 1179-89, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18490475

ABSTRACT

BACKGROUND: Various tibial dimensions and geometric parameters have been linked to stress fractures in athletes and military recruits, but many mechanical parameters have still not been investigated. HYPOTHESES: Sedentary people, athletes with medial tibial stress syndrome, and athletes with stress fractures have smaller tibial geometric dimensions and parameters than do uninjured athletes. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Using a total of 88 subjects, male and female patients with either a tibial stress fracture or medial tibial stress syndrome were compared with both uninjured aerobically active controls and uninjured sedentary controls. Tibial scout radiographs and cross-sectional computed tomography images of all subjects were scanned at the junction of the midthird and distal third of the tibia. Tibial dimensions were measured directly from the films; other parameters were calculated numerically. RESULTS: Uninjured exercising men have a greater tibial cortical cross-sectional area than do their sedentary and injured counterparts, resulting in a greater value of some other cross-sectional geometric parameters, particularly the section modulus. However, for women, the cross-sectional areas are either not different or only marginally different, and there are few tibial dimensions or geometric parameters that distinguish the uninjured exercisers from the sedentary and injured subjects. In women, the main difference between the groups was the distribution of cortical bone about the centroid as a result of the different values of section modulus. Last, medial tibial stress syndrome subjects had smaller tibial cross-sectional dimensions than did their uninjured exercising counterparts, suggesting that medial tibial stress syndrome is not just a soft-tissue injury but also a bony injury. CONCLUSION: The results show that in men, the cross-sectional area and the section modulus are the key parameters in the tibia to distinguish exercise and injury status, whereas for women, it is the section modulus only.


Subject(s)
Fractures, Stress/pathology , Sports/physiology , Tibia/anatomy & histology , Tibial Fractures/pathology , Adult , Body Size , Case-Control Studies , Cohort Studies , Exercise/physiology , Female , Humans , Male , Multivariate Analysis , Sex Factors , Statistics, Nonparametric , Tibia/injuries
6.
Genetics ; 171(1): 269-78, 2005 Sep.
Article in English | MEDLINE | ID: mdl-15956665

ABSTRACT

Dispensable, supernumerary (B) chromosomes are found in diverse eukaryotic species. The origin and genetic consequences of B chromosomes have been the subjects of speculation for more than a century. Until now, there has been no molecular evidence that B chromosome DNA is transcribed and there is no unequivocal evidence as to their origin. B chromosomes are considered to be genetically inert although they appear to cause a variety of phenotypic effects. We report that members of one of two ribosomal RNA gene families that are confined to the B chromosomes of a plant, Crepis capillaris, are transcribed--thus providing the first molecular evidence of gene activity on B chromosomes. Sequence analysis of part of the A and B chromosome rRNA genes, together with comparisons with related species, indicates that the B chromosome rRNA genes originate from the A chromosome.


Subject(s)
Chromosome Aberrations , Chromosomes, Plant/genetics , Crepis/genetics , Transcription, Genetic/genetics , Base Sequence , DNA, Plant/chemistry , DNA, Plant/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , DNA, Ribosomal Spacer/genetics , Flowers/genetics , Gene Expression Regulation, Plant , In Situ Hybridization, Fluorescence , Molecular Sequence Data , Phylogeny , Plant Leaves/genetics , RNA, Ribosomal/genetics , RNA, Ribosomal, 5.8S/genetics , Reverse Transcriptase Polymerase Chain Reaction , Sequence Alignment , Sequence Analysis, DNA , Sequence Homology, Nucleic Acid
7.
J Res Natl Inst Stand Technol ; 95(3): 237-253, 1990.
Article in English | MEDLINE | ID: mdl-28179777

ABSTRACT

This document describes the procedures used at NIST to calibrate dc voltage standards in terms of the NIST volt. Three calibration services are offered by the Electricity Division: Regular Calibration Service (RCS) of client standard cells at NIST; the Volt Transfer Program (VTP) a process to determine the difference between the NIST volt and the volt as maintained by a group of standard cells in a client laboratory; and the calibration of client solid-state dc voltage standards at NIST. The operational procedures used to compare these voltage standards to NIST voltage standards and to maintain the NIST volt via the ac Josephson effect are discussed.

8.
J Res Natl Bur Stand A Phys Chem ; 76A(4): 321-328, 1972.
Article in English | MEDLINE | ID: mdl-34565864

ABSTRACT

This paper gives the results of new measurements of the effect of temperature on the electromotive force of standard cells of the saturated cadmium sulfate type. Measurements were made over the temperature range of 15 to 40 °C. Twelve cells of NBS manufacture and twenty-four cells supplied by two different commercial manufacturers were used in the studies. Final results were analyzed by the method of least squares using computer programs. The relation between emf and temperature for NBS, company 1, and company 2 cells was found to be given, respectively, by: E t = E 20 ° C - [ 40.44 ( t - 20 ) + 0.921 ( t - 20 ) 2 - 0.00866 ( t - 20 ) 3 ] × 10 - 6 V E t = E 20 ° C - [ 40.14 ( t - 20 ) + 0.888 ( t - 20 ) 2 - 0.00668 ( t - 20 ) 3 ] × 10 - 6 V E t = E 20 ° C - [ 39.28 ( t - 20 ) + 0.986 ( t - 20 ) 2 - 0.00943 ( t - 20 ) 3 ] × 10 - 6 V Values for the entropy and heat-capacity changes for the cell reaction in "acid" standard cells are also given.

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