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https://www.readbyqxmd.com/read/28449257/the-development-and-application-of-random-match-probabilities-to-firearm-and-toolmark-identification
#1
John E Murdock, Nicholas D K Petraco, John I Thornton, Michael T Neel, Todd J Weller, Robert M Thompson, James E Hamby, Eric R Collins
The field of firearms and toolmark analysis has encountered deep scrutiny of late, stemming from a handful of voices, primarily in the law and statistical communities. While strong scrutiny is a healthy and necessary part of any scientific endeavor, much of the current criticism leveled at firearm and toolmark analysis is, at best, misinformed and, at worst, punditry. One of the most persistent criticisms stems from the view that as the field lacks quantified random match probability data (or at least a firm statistical model) with which to calculate the probability of a false match, all expert testimony concerning firearm and toolmark identification or source attribution is unreliable and should be ruled inadmissible...
May 2017: Journal of Forensic Sciences
https://www.readbyqxmd.com/read/28448739/health-economic-evaluation-of-immunization-strategies-of-hepatitis-e-vaccine-for-elderly-population
#2
Xiaoqing Cheng, Yueyuan Zhao, Xuefeng Zhang, Hui Jin, Jin Min
Objective This study was conducted to assess the cost-effectiveness of hepatitis E vaccination of elderly population in the sporadic regions in China. Methods We used a decision tree-Markov model to evaluate the cost-effectiveness of three kinds of hepatitis E virus vaccination strategies from societal perspectives. Parameter estimates were obtained from published researches and experts' opinion. The time horizon was 16 years, and the discounted rate was 3% annually. Costs are expressed in 2016 US dollars...
April 27, 2017: Human Vaccines & Immunotherapeutics
https://www.readbyqxmd.com/read/28446703/efficient-use-of-sentinel-sites-detection-of-invasive-honeybee-pests-and-diseases-in-the-uk
#3
Matt J Keeling, Samik Datta, Daniel N Franklin, Ivor Flatman, Andy Wattam, Mike Brown, Giles E Budge
Sentinel sites, where problems can be identified early or investigated in detail, form an important part of planning for exotic disease outbreaks in humans, livestock and plants. Key questions are: how many sentinels are required, where should they be positioned and how effective are they at rapidly identifying new invasions? The sentinel apiary system for invasive honeybee pests and diseases illustrates the costs and benefits of such approaches. Here, we address these issues with two mathematical modelling approaches...
April 2017: Journal of the Royal Society, Interface
https://www.readbyqxmd.com/read/28444463/cost-effectiveness-of-craniotomy-for-epidural-hematomas-at-a-major-government-hospital-in-cambodia
#4
Dane Moran, Mark G Shrime, Sam Nang, Iv Vycheth, Din Vuthy, Raksmey Hong, William V Padula, Kee B Park
BACKGROUND: Epidural hematoma (EDH) is a common and potentially deadly occurrence following a severe traumatic brain injury. Our aim was to determine whether craniotomy is cost-effective when indicated for the treatment of EDH when a trained neurosurgeon is available. METHODS: A decision tree was used to model the cost-effectiveness of craniotomy available versus craniotomy unavailable for the management of traumatic EDH from a Cambodian societal and provider perspective...
April 25, 2017: World Journal of Surgery
https://www.readbyqxmd.com/read/28444137/effects-of-serotonin-transporter-gene-variation-on-impulsivity-mediated-by-default-mode-network-a-family-study-of-depression
#5
Jiook Cha, Guia Guffanti, Jay Gingrich, Ardesheer Talati, Priya Wickramaratne, Myrna Weissman, Jonathan Posner
Serotonergic neurotransmission, potentially through effects on the brain's default mode network (DMN), may regulate aspects of attention including impulse control. Indeed, genetic variants of the serotonin transporter (5-HTT) have been implicated in impulsivity and related psychopathology. Yet it remains unclear the mechanism by which the 5-HTT genetic variants contribute to individual variability in impulse control. Here, we tested whether DMN connectivity mediates an association between the 5-HTT genetic variants and impulsivity...
April 21, 2017: Cerebral Cortex
https://www.readbyqxmd.com/read/28442144/a-proposal-to-evaluate-the-fibers-break-probability-in-ligaments-and-tendons
#6
Marco Bontempi
Understanding the yield and failure mechanisms of ligaments and tendons is important to have a deeper knowledge of their structure and function. Evaluating what are the limits of the human body is also important to prevent injuries in workers, in athletes and the elderly. The tissue yield mechanism was analyzed by modifying and extending a probabilistic model of collagen bundles. Since not usable experimental data are available in the literature, the model and the method were tested using Monte Carlo simulations...
April 13, 2017: Journal of Biomechanics
https://www.readbyqxmd.com/read/28441977/detecting-clusters-in-atom-probe-data-with-gaussian-mixture-models
#7
Jennifer Zelenty, Andrew Dahl, Jonathan Hyde, George D W Smith, Michael P Moody
Accurately identifying and extracting clusters from atom probe tomography (APT) reconstructions is extremely challenging, yet critical to many applications. Currently, the most prevalent approach to detect clusters is the maximum separation method, a heuristic that relies heavily upon parameters manually chosen by the user. In this work, a new clustering algorithm, Gaussian mixture model Expectation Maximization Algorithm (GEMA), was developed. GEMA utilizes a Gaussian mixture model to probabilistically distinguish clusters from random fluctuations in the matrix...
April 2017: Microscopy and Microanalysis
https://www.readbyqxmd.com/read/28439014/brain-networks-for-confidence-weighting-and-hierarchical-inference-during-probabilistic-learning
#8
Florent Meyniel, Stanislas Dehaene
Learning is difficult when the world fluctuates randomly and ceaselessly. Classical learning algorithms, such as the delta rule with constant learning rate, are not optimal. Mathematically, the optimal learning rule requires weighting prior knowledge and incoming evidence according to their respective reliabilities. This "confidence weighting" implies the maintenance of an accurate estimate of the reliability of what has been learned. Here, using fMRI and an ideal-observer analysis, we demonstrate that the brain's learning algorithm relies on confidence weighting...
April 24, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28438523/predictors-of-early-childbirth-among-female-adolescents-in-foster-care
#9
Bryn King, Melissa Van Wert
PURPOSE: Placement into foster care is driven by a number of factors, many of which are associated with adolescent childbirth. Yet, there are few studies that identify the experiences and characteristics that predict adolescent childbirth among girls who spend time in foster care. METHODS: A longitudinal, population-based data set was constructed by probabilistically matching California child protective service records for female foster youth to maternal information available on vital birth records for children born between 2001 and 2010...
April 21, 2017: Journal of Adolescent Health: Official Publication of the Society for Adolescent Medicine
https://www.readbyqxmd.com/read/28436898/extended-polynomial-growth-transforms-for-design-and-training-of-generalized-support-vector-machines
#10
Ahana Gangopadhyay, Oindrila Chatterjee, Shantanu Chakrabartty
Growth transformations constitute a class of fixed-point multiplicative update algorithms that were originally proposed for optimizing polynomial and rational functions over a domain of probability measures. In this paper, we extend this framework to the domain of bounded real variables which can be applied towards optimizing the dual cost function of a generic support vector machine (SVM). The approach can, therefore, not only be used to train traditional soft-margin binary SVMs, one-class SVMs, and probabilistic SVMs but can also be used to design novel variants of SVMs with different types of convex and quasi-convex loss functions...
April 17, 2017: IEEE Transactions on Neural Networks and Learning Systems
https://www.readbyqxmd.com/read/28436850/pulmonary-lobe-segmentation-with-probabilistic-segmentation-of-the-fissures-and-a-groupwise-fissure-prior
#11
Felix Bragman, Jamie McClelland, Joseph Jacob, John Hurst, David Hawkes
A fully automated, unsupervised lobe segmentation algorithm is presented based on a probabilistic segmentation of the fissures and the simultaneous construction of a population model of the fissures. A two-class probabilistic segmentation segments the lung into candidate fissure voxels and the surrounding parenchyma. This was combined with anatomical information and a groupwise fissure prior to drive non-parametric surface fitting to obtain the final segmentation. The performance of our fissure segmentation was validated on 30 patients from the COPDGene cohort, achieving a high median F1-score of 0:90 and showed general insensitivity to filter parameters...
April 18, 2017: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/28436847/learning-trans-dimensional-random-fields-with-applications-to-language-modeling
#12
Bin Wang, Zhijian Ou, Zhiqiang Tan
To describe trans-dimensional observations in sample spaces of different dimensions, we propose a probabilistic model, called the trans-dimensional random field (TRF) by explicitly mixing a collection of random fields. In the framework of stochastic approximation (SA), we develop an effective training algorithm, called augmented SA, which jointly estimates the model parameters and normalizing constants while using trans-dimensional mixture sampling to generate observations of different dimensions. Furthermore, we introduce several statistical and computational techniques to improve the convergence of the training algorithm and reduce computational cost, which together enable us to successfully train TRF models on large datasets...
April 24, 2017: IEEE Transactions on Pattern Analysis and Machine Intelligence
https://www.readbyqxmd.com/read/28436844/probabilistic-elastic-part-model-a-pose-invariant-representation-for-real-world-face-verification
#13
Haoxiang Li, Gang Hua
Pose variation remains to be a major challenge for real-world face recognition. We approach this problem through a probabilistic elastic part model. We extract local descriptors (e.g., LBP or SIFT) from densely sampled multi-scale image patches. By augmenting each descriptor with its location, a Gaussian mixture model (GMM) is trained to capture the spatial-appearance distribution of the face parts of all face images in the training corpus, namely the probabilistic elastic part (PEP) model. Each mixture component of the GMM is confined to be a spherical Gaussian to balance the influence of the appearance and the location terms, which naturally defines a part...
April 18, 2017: IEEE Transactions on Pattern Analysis and Machine Intelligence
https://www.readbyqxmd.com/read/28434560/accelerated-fatigue-testing-of-dentin-composite-bond-with-continuously-increasing-load
#14
Kai Li, Jiawen Guo, Yuping Li, Young Cheul Heo, Jihua Chen, Haitao Xin, Alex Fok
OBJECTIVES: The aim of this study was to evaluate an accelerated fatigue test method that used a continuously increasing load for testing the dentin-composite bond strength. METHODS: Dentin-composite disks (ϕ5mm×2mm) made from bovine incisor roots were subjected to cyclic diametral compression with a continuously increasingly load amplitude. Two different load profiles, linear and nonlinear with respect to the number of cycles, were considered. The data were then analyzed by using a probabilistic failure model based on the Weakest-Link Theory and the classical stress-life function, before being transformed to simulate clinical data of direct restorations...
April 20, 2017: Dental Materials: Official Publication of the Academy of Dental Materials
https://www.readbyqxmd.com/read/28433588/how-environmental-noise-can-contract-and-destroy-a-persistence-zone-in-population-models-with-allee-effect
#15
Irina Bashkirtseva, Lev Ryashko
A problem of the analysis of the noise-induced extinction in population models with Allee effect is considered. To clarify mechanisms of the extinction, we suggest a new technique combining an analysis of the geometry of attractors and their stochastic sensitivity. For the conceptual one-dimensional discrete Ricker-type model, on the base of the bifurcation analysis, deterministic persistence zones are constructed in the space of initial states and biological parameters. It is shown that the random environmental noise can contract, and even destroy these persistence zones...
April 19, 2017: Theoretical Population Biology
https://www.readbyqxmd.com/read/28433383/screening-for-chronic-kidney-disease-in-canadian-indigenous-peoples-is-cost-effective
#16
Thomas W Ferguson, Navdeep Tangri, Zhi Tan, Matthew T James, Barry D A Lavallee, Caroline D Chartrand, Lorraine L McLeod, Allison B Dart, Claudio Rigatto, Paul V J Komenda
Canadian indigenous (First Nations) have rates of kidney failure that are 2- to 4-fold higher than the non-indigenous general Canadian population. As such, a strategy of targeted screening and treatment for CKD may be cost-effective in this population. Our objective was to assess the cost utility of screening and subsequent treatment for CKD in rural Canadian indigenous adults by both estimated glomerular filtration rate and the urine albumin-to-creatinine ratio. A decision analytic Markov model was constructed comparing the screening and treatment strategy to usual care...
April 19, 2017: Kidney International
https://www.readbyqxmd.com/read/28432822/focal-liver-lesions-segmentation-and-classification-in-nonenhanced-t2-weighted-mri
#17
Ilias Gatos, Stavros Tsantis, Maria Karamesini, Stavros Spiliopoulos, Dimitris Karnabatidis, John D Hazle, George C Kagadis
PURPOSE: To automatically segment and classify focal liver lesions (FLLs) on nonenhanced T2-weighted magnetic resonance imaging (MRI) scans using a computer-aided diagnosis (CAD) algorithm. METHODS: 71 FLLs (30 benign lesions, 19 hepatocellular carcinomas, and 22 metastases) on T2-weighted MRI scans were delineated by the proposed CAD scheme. The FLL segmentation procedure involved wavelet multiscale analysis to extract accurate edge information and mean intensity values for consecutive edges computed using horizontal and vertical analysis that were fed into the subsequent fuzzy C-means algorithm for final FLL border extraction...
April 22, 2017: Medical Physics
https://www.readbyqxmd.com/read/28432778/cross-species-studies-of-cognition-relevant-to-drug-discovery-a-translational-approach
#18
REVIEW
T W Robbins
This Review advances the case that bidirectional, cross-species translation of findings from experimental animals to and from humans is an important strategy for drug discovery. Animal models of mental disorders require appropriate behavioural or cognitive outcome variables that can be generalized cross-species. One example is the treatment of impulsive behaviour in attention deficit hyperactivity disorder (ADHD) with stimulant drugs. Performance on the stop signal reaction task as an index of impulsivity is improved both in healthy human volunteers and in patients with adult ADHD by stimulant drugs and also by the selective noradrenergic reuptake blocker atomoxetine...
April 22, 2017: British Journal of Pharmacology
https://www.readbyqxmd.com/read/28432423/note-on-the-coefficient-of-variations-of-neuronal-spike-trains
#19
Johannes Lengler, Angelika Steger
It is known that many neurons in the brain show spike trains with a coefficient of variation (CV) of the interspike times of approximately 1, thus resembling the properties of Poisson spike trains. Computational studies have been able to reproduce this phenomenon. However, the underlying models were too complex to be examined analytically. In this paper, we offer a simple model that shows the same effect but is accessible to an analytic treatment. The model is a random walk model with a reflecting barrier; we give explicit formulas for the CV in the regime of excess inhibition...
April 21, 2017: Biological Cybernetics
https://www.readbyqxmd.com/read/28431415/potential-impact-of-affordable-care-act-related-insurance-expansion-on-trauma-care-reimbursement
#20
John W Scott, Pooja U Neiman, Peter A Najjar, Thomas C Tsai, Kirstin W Scott, Mark G Shrime, David M Cutler, Ali Salim, Adil H Haider
BACKGROUND: Nearly one quarter of trauma patients are uninsured and hospitals recoup less than 20% of inpatient costs for their care. This study examines changes to hospital reimbursement for inpatient trauma care if the full coverage expansion provisions of the Affordable Care Act (ACA) were in effect. METHODS: We abstracted nonelderly adults (ages 18-64 years) admitted for trauma from the Nationwide Inpatient Sample during 2010-the last year before most major ACA coverage expansion policies...
May 2017: Journal of Trauma and Acute Care Surgery
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