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https://www.readbyqxmd.com/read/28324092/association-between-choice-of-radical-prostatectomy-external-beam-radiotherapy-brachytherapy-or-active-surveillance-and-patient-reported-quality-of-life-among-men-with-localized-prostate-cancer
#1
Ronald C Chen, Ramsankar Basak, Anne-Marie Meyer, Tzy-Mey Kuo, William R Carpenter, Robert P Agans, James R Broughman, Bryce B Reeve, Matthew E Nielsen, Deborah S Usinger, Kiayni C Spearman, Sarah Walden, Dianne Kaleel, Mary Anderson, Til Stürmer, Paul A Godley
Importance: Patients diagnosed with localized prostate cancer have to decide among treatment strategies that may differ in their likelihood of adverse effects. Objective: To compare quality of life (QOL) after radical prostatectomy, external beam radiotherapy, and brachytherapy vs active surveillance. Design, Setting, and Participants: Population-based prospective cohort of 1141 men (57% participation among eligible men) with newly diagnosed prostate cancer were enrolled from January 2011 through June 2013 in collaboration with the North Carolina Central Cancer Registry...
March 21, 2017: JAMA: the Journal of the American Medical Association
https://www.readbyqxmd.com/read/28316883/middle-pleistocene-protein-sequences-from-the-rhinoceros-genus-stephanorhinus-and-the-phylogeny-of-extant-and-extinct-middle-late-pleistocene-rhinocerotidae
#2
Frido Welker, Geoff M Smith, Jarod M Hutson, Lutz Kindler, Alejandro Garcia-Moreno, Aritza Villaluenga, Elaine Turner, Sabine Gaudzinski-Windheuser
BACKGROUND: Ancient protein sequences are increasingly used to elucidate the phylogenetic relationships between extinct and extant mammalian taxa. Here, we apply these recent developments to Middle Pleistocene bone specimens of the rhinoceros genus Stephanorhinus. No biomolecular sequence data is currently available for this genus, leaving phylogenetic hypotheses on its evolutionary relationships to extant and extinct rhinoceroses untested. Furthermore, recent phylogenies based on Rhinocerotidae (partial or complete) mitochondrial DNA sequences differ in the placement of the Sumatran rhinoceros (Dicerorhinus sumatrensis)...
2017: PeerJ
https://www.readbyqxmd.com/read/28303174/local-site-differences-in-survival-and-parasitism-of-periwinkles-littorina-sitkana-philippi-1846
#3
Mónica Ayala-Díaz, Jean M L Richardson, Bradley R Anholt
The periwinkle, Littorina sitkana, is found throughout the intertidal zone, often in isolated subpopulations. The majority of trematode parasites use snails as intermediate hosts, and decreased survivorship is often observed in snails infected with trematodes. Sampling L. sitkana from four sites in Barkley Sound, British Columbia, Canada, we test the effects of parasitic infection on snail survival using maximum likelihood and Bayesian approaches using the software MARK and WinBUGS. We found that survival of periwinkles and trematode community composition differed among sites, but survival and trematode prevalence were uncorrelated...
February 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28299958/a-model-of-self-monitoring-blood-glucose-measurement-error
#4
Martina Vettoretti, Andrea Facchinetti, Giovanni Sparacino, Claudio Cobelli
BACKGROUND: A reliable model of the probability density function (PDF) of self-monitoring of blood glucose (SMBG) measurement error would be important for several applications in diabetes, like testing in silico insulin therapies. In the literature, the PDF of SMBG error is usually described by a Gaussian function, whose symmetry and simplicity are unable to properly describe the variability of experimental data. Here, we propose a new methodology to derive more realistic models of SMBG error PDF...
March 1, 2017: Journal of Diabetes Science and Technology
https://www.readbyqxmd.com/read/28299468/gw-sem-a-statistical-package-to-conduct-genome-wide-structural-equation-modeling
#5
Brad Verhulst, Hermine H Maes, Michael C Neale
Improving the accuracy of phenotyping through the use of advanced psychometric tools will increase the power to find significant associations with genetic variants and expand the range of possible hypotheses that can be tested on a genome-wide scale. Multivariate methods, such as structural equation modeling (SEM), are valuable in the phenotypic analysis of psychiatric and substance use phenotypes, but these methods have not been integrated into standard genome-wide association analyses because fitting a SEM at each single nucleotide polymorphism (SNP) along the genome was hitherto considered to be too computationally demanding...
March 15, 2017: Behavior Genetics
https://www.readbyqxmd.com/read/28296913/breeding-jatropha-curcas-by-genomic-selection-a-pilot-assessment-of-the-accuracy-of-predictive-models
#6
Leonardo de Azevedo Peixoto, Bruno Galvêas Laviola, Alexandre Alonso Alves, Tatiana Barbosa Rosado, Leonardo Lopes Bhering
Genomic wide selection is a promising approach for improving the selection accuracy in plant breeding, particularly in species with long life cycles, such as Jatropha. Therefore, the objectives of this study were to estimate the genetic parameters for grain yield (GY) and the weight of 100 seeds (W100S) using restricted maximum likelihood (REML); to compare the performance of GWS methods to predict GY and W100S; and to estimate how many markers are needed to train the GWS model to obtain the maximum accuracy...
2017: PloS One
https://www.readbyqxmd.com/read/28296797/improvements-in-spectrum-s-fit-to-program-data-tool
#7
Severin G Mahiane, Kimberly Marsh, Kelsey Grantham, Shawna Crichlow, Karen Caceres, John Stover
OBJECTIVE: The Joint United Nations Program on HIV/AIDS-supported Spectrum software package (Glastonbury, Connecticut, USA) is used by most countries worldwide to monitor the HIV epidemic. In Spectrum, HIV incidence trends among adults (aged 15-49 years) are derived by either fitting to seroprevalence surveillance and survey data or generating curves consistent with program and vital registration data, such as historical trends in the number of newly diagnosed infections or people living with HIV and AIDS related deaths...
April 2017: AIDS
https://www.readbyqxmd.com/read/28295486/estimating-efficacy-in-trials-with-selective-crossover
#8
Adam R Brentnall, Peter Sasieni, Jack Cuzick
When one arm in a trial has a worse early endpoint such as recurrence, a data-monitoring committee might recommend that all participants are offered the apparently superior treatment. The resultant crossover makes it difficult to measure differences between arms thereafter, including for longer-term endpoints such as mortality and disease-specific mortality. In this paper, we consider estimators of the efficacy of treatment on those who would not cross over if randomised to the apparently inferior arm. Binomial and proportional hazards maximum likelihood estimators are developed...
March 15, 2017: Statistics in Medicine
https://www.readbyqxmd.com/read/28295456/firth-s-logistic-regression-with-rare-events-accurate-effect-estimates-and-predictions
#9
Rainer Puhr, Georg Heinze, Mariana Nold, Lara Lusa, Angelika Geroldinger
Firth's logistic regression has become a standard approach for the analysis of binary outcomes with small samples. Whereas it reduces the bias in maximum likelihood estimates of coefficients, bias towards one-half is introduced in the predicted probabilities. The stronger the imbalance of the outcome, the more severe is the bias in the predicted probabilities. We propose two simple modifications of Firth's logistic regression resulting in unbiased predicted probabilities. The first corrects the predicted probabilities by a post hoc adjustment of the intercept...
March 12, 2017: Statistics in Medicine
https://www.readbyqxmd.com/read/28295095/first-experimental-demonstration-of-faster-than-nyquist-pdm-16qam-transmission-over-standard-single-mode-fiber
#10
Zhuopeng Xiao, B Li, Songnian Fu, L Deng, M Tang, Deming Liu
We demonstrate faster-than-Nyquist (FTN) transmission with a novel mitigation scheme of intercarrier interference. To the best of our knowledge, it is the first experimental demonstration of FTN PDM-16QAM transmission over standard single mode fiber (SSMF). Due to the use of maximum likelihood sequence detection and multi-input multi-output processing for severely overlapped Nyquist-PDM-16QAM carriers, 5.4-dB optical signal-to-noise ratio improvement is experimentally observed under the scenario of 2×16-GBd PDM-16QAM back-to-back transmission with a carrier spacing of 15 GHz...
March 15, 2017: Optics Letters
https://www.readbyqxmd.com/read/28294388/interpretable-inference-on-the-mixed-effect-model-with-the-box-cox-transformation
#11
K Maruo, Y Yamaguchi, H Noma, M Gosho
We derived results for inference on parameters of the marginal model of the mixed effect model with the Box-Cox transformation based on the asymptotic theory approach. We also provided a robust variance estimator of the maximum likelihood estimator of the parameters of this model in consideration of the model misspecifications. Using these results, we developed an inference procedure for the difference of the model median between treatment groups at the specified occasion in the context of mixed effects models for repeated measures analysis for randomized clinical trials, which provided interpretable estimates of the treatment effect...
March 10, 2017: Statistics in Medicine
https://www.readbyqxmd.com/read/28294341/reconstruction-of-uptake-patterns-in-pet-the-influence-of-regularizing-priors
#12
Elisabetta De Bernardi, Federico Fallanca, Luigi Gianolli, Maria Carla Gilardi, Valentino Bettinardi
PURPOSE: The effects of regularizing priors on the maximum likelihood (ML) reconstruction of activity patterns in Positron Emission Tomography (PET) was assessed. METHODS: Two edge-preserving priors (one originally proposed by Nuyts et al. and nowadays implemented and commercialized by General Electric Medical Systems as Q.Clear software, and a second one originally proposed by Rapisarda et al. and our group) were assessed and compared to a standard Ordered Subset (OS)-ML reconstruction, assumed as reference...
March 11, 2017: Medical Physics
https://www.readbyqxmd.com/read/28291487/physical-screening-predictors-for-success-in-completing-air-force-phase-ii-air-liaison-officer-aptitude-assessment
#13
John Christopher McGee, Eric Wilson, Haley Barela, Sharon Blum
OBJECTIVES: Air Liaison Officer Aptitude Assessment (AAA) attrition is often associated with a lack of candidate physical preparation. The Functional Movement Screen, Tactical Fitness Assessment, and fitness metrics were collected (n = 29 candidates) to determine what physical factors could predict a candidate s success in completing AAA. METHODS: Between-group comparisons were made between candidates completing AAA versus those who did not (p < 0.05). Upper 50% thresholds were established for all variables with R(2) < 0...
March 2017: Military Medicine
https://www.readbyqxmd.com/read/28290309/polydactyly-suggesting-local-husbandry-of-pre-columbian-camelids-a-case-from-castillo-de-huarmey-archaeological-site-northern-coast-of-peru
#14
Weronika Tomczyk, Miłosz Giersz
Three camelid metapodials with polydactyly (additional digits) were found at the Wari culture archaeological site (dated to the Middle Horizon) of Castillo de Huarmey. The anomalous bones were excavated among numerous remains, and presumably represent animals that were sacrificed within the principal mortuary mausoleum. The bones derive from at least two individuals. The etiology of the deformities remains unknown, but the most probable causes include low genetic diversity in the herd or unintended effect of selective breeding...
March 2017: International Journal of Paleopathology
https://www.readbyqxmd.com/read/28290111/generalized-network-psychometrics-combining-network-and-latent-variable-models
#15
Sacha Epskamp, Mijke Rhemtulla, Denny Borsboom
We introduce the network model as a formal psychometric model, conceptualizing the covariance between psychometric indicators as resulting from pairwise interactions between observable variables in a network structure. This contrasts with standard psychometric models, in which the covariance between test items arises from the influence of one or more common latent variables. Here, we present two generalizations of the network model that encompass latent variable structures, establishing network modeling as parts of the more general framework of structural equation modeling (SEM)...
March 13, 2017: Psychometrika
https://www.readbyqxmd.com/read/28289556/molecular-characterization-and-genetic-diversity-of-jatropha-curcas-l-in-costa-rica
#16
Marcela Vásquez-Mayorga, Eric J Fuchs, Eduardo J Hernández, Franklin Herrera, Jesús Hernández, Ileana Moreira, Elizabeth Arnáez, Natalia M Barboza
We estimated the genetic diversity of 50 Jatropha curcas samples from the Costa Rican germplasm bank using 18 EST-SSR, one G-SSR and nrDNA-ITS markers. We also evaluated the phylogenetic relationships among samples using nuclear ribosomal ITS markers. Non-toxicity was evaluated using G-SSRs and SCARs markers. A Neighbor-Joining (NJ) tree and a Maximum Likelihood (ML) tree were constructed using SSR markers and ITS sequences, respectively. Heterozygosity was moderate (He = 0.346), but considerable compared to worldwide values for J...
2017: PeerJ
https://www.readbyqxmd.com/read/28288549/the-psychometric-properties-of-the-reading-the-mind-in-the-eyes-test-an-item-response-theory-irt-analysis
#17
Antonio Preti, Marcello Vellante, Donatella R Petretto
INTRODUCTION: The "Reading the Mind in the Eyes" Test (hereafter: Eyes Test) is considered an advanced task of the Theory of Mind aimed at assessing the performance of the participant in perspective-takingthat is, the ability to sense or understand other people's cognitive and emotional states. In this study, the item response theory analysis was applied to the adult version of the Eyes Test. METHODS: The Italian version of the Eyes Test was administered to 200 undergraduate students of both genders (males = 46%)...
March 13, 2017: Cognitive Neuropsychiatry
https://www.readbyqxmd.com/read/28288166/the-relationships-within-the-chaitophorinae-and-drepanosiphinae-hemiptera-aphididae-inferred-from-molecular-based-phylogeny-and-comprehensive-morphological-data
#18
Karina Wieczorek, Dorota Lachowska-Cierlik, Łukasz Kajtoch, Mariusz Kanturski
The Chaitophorinae is a bionomically diverse Holarctic subfamily of Aphididae. The current classification includes two tribes: the Chaitophorini associated with deciduous trees and shrubs, and Siphini that feed on monocotyledonous plants. We present the first phylogenetic hypothesis for the subfamily, based on molecular and morphological datasets. Molecular analyses were based on the mitochondrial gene cytochrome oxidase subunit I (COI) and the nuclear gene elongation factor-1α (EF-1α). Phylogenetic inferences were obtained individually on each of genes and joined alignments using Bayesian inference (BI) and Maximum likelihood (ML)...
2017: PloS One
https://www.readbyqxmd.com/read/28288156/parameter-estimation-for-multistage-clonal-expansion-models-from-cancer-incidence-data-a-practical-identifiability-analysis
#19
Andrew F Brouwer, Rafael Meza, Marisa C Eisenberg
Many cancers are understood to be the product of multiple somatic mutations or other rate-limiting events. Multistage clonal expansion (MSCE) models are a class of continuous-time Markov chain models that capture the multi-hit initiation-promotion-malignant-conversion hypothesis of carcinogenesis. These models have been used broadly to investigate the epidemiology of many cancers, assess the impact of carcinogen exposures on cancer risk, and evaluate the potential impact of cancer prevention and control strategies on cancer rates...
March 13, 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28287747/assessment-of-gold-nano-particle-mediated-enhanced-hyperthermia-using-mr-guided-high-intensity-focused-ultrasound-ablation-procedure
#20
Surendra Balaji Devarakonda, Matthew R Myers, Matthew Lanier, Charles Dumoulin, Rupak Kumar Banerjee
High-intensity focused ultrasound (HIFU) has gained increasing popularity as a non-invasive therapeutic procedure to treat solid tumors. However, collateral damage due to the use of high acoustic powers during HIFU procedures remains a challenge. The objective of this study is to assess the utility of using gold nano-particles (gNPs) during HIFU procedures to locally enhance heating at low powers, thereby reducing the likelihood of collateral damage. Phantoms containing tissue-mimicking material (TMM) and physiologically relevant concentrations (0%, 0...
March 13, 2017: Nano Letters
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