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maximum likelihood

Liuyu Wu, Xiao Xiong, Xuming Wang, Tianrong Xin, Jing Wang, Zhiwen Zou, Bin Xia
The bluish yellow lappet moth, Trabala vishnou guttata is an extraordinarily important pest in China. The complete mitochondrial genome is sequenced and determined firstly, which is based on traditional PCR amplification and primer walking methods with a length of 15,281 bp, including 13 protein-coding (PCG) genes, 22 transfer RNA (rRNA) genes, two ribosomal RNA (tRNA) genes, and an A + T-rich region. The gene order and orientation of the T. vishnou guttata mitogenome were identical to the other sequenced Lasiocampidae species...
October 21, 2016: Genetica
Toby N Weingarten, Tasha L Welch, Tamara L Moore, Gulshat F Walters, Joni L Whipple, Alexandre Cavalcante, Irina Bancos, William F Young, Lucinda M Gruber, Muhammad Z Shah, Travis J McKenzie, Darrell R Schroeder, Juraj Sprung
OBJECTIVE: To determine whether, despite pharmacologic adrenergic receptor blockade, higher preoperative levels of catecholamines and metanephrines (adrenergic activity) are associated with increased intraoperative complications. METHODS: Records of patients undergoing paraganglioma and pheochromocytoma (PGL-PCC) resection from January 1, 2000, through June 31, 2015, were reviewed for preoperative levels of adrenergic activity, intraoperative variability in blood pressure and heart rate (range), and postoperative outcomes (hypotension requiring treatment)...
October 18, 2016: Urology
Qiu-Ning Liu, Zhao-Zhe Xin, Dan-Dan Bian, Xin-Yue Chai, Chun-Lin Zhou, Bo-Ping Tang
The mitochondrial genome (mitogenome) provides important information for understanding molecular evolution and phylogeny. To determine the systematic status of the family Limacodidae within Lepidoptera, we infer a phylogenetic hypothesis based on the complete mitogenome of Monema flavescens (Lepidoptera: Limacodidae). The mitogenome of M. flavescens is 15,396 base pairs (bp), and includes 13 protein-coding genes (PCGs), two ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and a control region (CR)...
October 21, 2016: Scientific Reports
Sarah Thabet, Nada Souissi
The mycobacterial insertion sequence IS6110 proved crucial in deciphering tuberculosis (TB) transmission dynamics. This sequence was also shown to play an important role in the pathogenicity (transmission ability and/or virulence) of Mycobacterium tuberculosis, the main causative agent of TB in humans. In this study, we explored the usefulness of IS6110 and its potential as a phylogenetic/typing marker. We also analyzed the genetic polymorphism and evolutionary trends (selective pressure) of its transposase-encoding open reading frames (ORFs), A and B, using the maximum likelihood method...
October 20, 2016: Molecular Biology Reports
E H Baker, S W Levin, Z Zhang, A B Mukherjee
BACKGROUND AND PURPOSE: Infantile neuronal ceroid lipofuscinosis is a devastating neurodegenerative storage disease caused by palmitoyl-protein thioesterase 1 deficiency, which impairs degradation of palmitoylated proteins (constituents of ceroid) by lysosomal hydrolases. Consequent lysosomal ceroid accumulation leads to neuronal injury, resulting in rapid neurodegeneration and childhood death. As part of a project studying the treatment benefits of a combination of cysteamine bitartrate and N-acetyl cysteine, we made serial measurements of patients' brain volumes with MR imaging...
October 20, 2016: AJNR. American Journal of Neuroradiology
W-Y Guo, C-C J Lee, C-J Lin, H-C Yang, H-M Wu, C-C Wu, W-Y Chung, K-D Liu
BACKGROUND AND PURPOSE: Sinus stenosis occasionally occurs in dural arteriovenous fistulas. Sinus stenosis impedes venous outflow and aggravates intracranial hypertension by reversing cortical venous drainage. This study aimed to analyze the likelihood of sinus stenosis and its impact on cerebral hemodynamics of various types of dural arteriovenous fistulas. MATERIALS AND METHODS: Forty-three cases of dural arteriovenous fistula in the transverse-sigmoid sinus were reviewed and divided into 3 groups: Cognard type I, type IIa, and types with cortical venous drainage...
October 20, 2016: AJNR. American Journal of Neuroradiology
Zhuanglin Ma, Honglu Zhang, Steven I-Jy Chien, Jin Wang, Chunjiao Dong
To investigate the relationship between crash frequency and potential influence factors, the accident data for events occurring on a 50km long expressway in China, including 567 crash records (2006-2008), were collected and analyzed. Both the fixed-length and the homogeneous longitudinal grade methods were applied to divide the study expressway section into segments. A negative binomial (NB) model and a random effect negative binomial (RENB) model were developed to predict crash frequency. The parameters of both models were determined using the maximum likelihood (ML) method, and the mixed stepwise procedure was applied to examine the significance of explanatory variables...
October 17, 2016: Accident; Analysis and Prevention
Zhuo Wang, Alan A Stocker, Daniel D Lee
The efficient coding hypothesis assumes that biological sensory systems use neural codes that are optimized to best possibly represent the stimuli that occur in their environment. Most common models use information-theoretic measures, whereas alternative formulations propose incorporating downstream decoding performance. Here we provide a systematic evaluation of different optimality criteria using a parametric formulation of the efficient coding problem based on the Lp reconstruction error of the maximum likelihood decoder...
October 20, 2016: Neural Computation
Christina Hunger, Lena Krause, Rebecca Hilzinger, Beate Ditzen, Jochen Schweitzer
There is a need of an economical, reliable, and valid instrument in the German-speaking countries to measure the burden of relatives who care for mentally ill persons. We translated the Burden Assessment Scale (BAS) and conducted a study investigating factor structure, psychometric quality and predictive validity. We used confirmative factor analyses (CFA, maximum-likelihood method) to examine the dimensionality of the German BAS in a sample of 215 relatives (72% women; M = 32 years, SD = 14, range: 18 to 77; 39% employed) of mentally ill persons (50% (ex-)partner or (best) friend; M = 32 years, SD = 13, range 8 to 64; main complaints were depression and/or anxiety)...
2016: PloS One
Elizabeth Wolf, Joshua Herbeck, Stephen Van Rompaey, Mari M Kitahata, Katherine K Thomas, Gregory Pepper, Lisa Frenkel
HIV-1 incidence among youth, especially men who have sex with men (MSM), is increasing in the US. We aimed to better understand the patterns of adolescent HIV-1 acquisition, in order to help guide future prevention interventions. We conducted a study combining epidemiologic and HIV-1 pol sequence data from a retrospective cohort of HIV-infected adults and adolescents in Seattle, WA between 2000 and 2013. Adolescents were defined as 13-24 years of age at the time of first HIV-1 care. Maximum-likelihood phylogenetic trees were reconstructed to identify putative viral transmission clusters of two or more individuals, followed by multivariable regression tests of associations between clustering and demographic and clinical parameters...
October 20, 2016: AIDS Research and Human Retroviruses
Joanna Malukiewicz, Crystal M Hepp, Katerina Guschanski, Anne C Stone
OBJECTIVES: Two subgroups make up the marmoset genus Callithrix. The "aurita" group is composed of two species, whereas evolutionary relationships among the four species of the "jacchus" group remain unclear. To uncover these relationships, we first sequenced mitochondrial genomes for C. kuhlii and C. penicillata to complement data available for congeners. We then constructed a phylogenetic tree based on mtDNA heavy chain protein coding genes from several primates to untangle species relationships and estimate divergence times of the jacchus group...
October 20, 2016: American Journal of Physical Anthropology
Edwin J Niklitschek, Audrey M Darnaude
BACKGROUND: Mixture models (MM) can be used to describe mixed stocks considering three sets of parameters: the total number of contributing sources, their chemical baseline signatures and their mixing proportions. When all nursery sources have been previously identified and sampled for juvenile fish to produce baseline nursery-signatures, mixing proportions are the only unknown set of parameters to be estimated from the mixed-stock data. Otherwise, the number of sources, as well as some/all nursery-signatures may need to be also estimated from the mixed-stock data...
2016: PeerJ
H Felix Fischer, Matthias Rose
BACKGROUND: Recently, a growing number of Item-Response Theory (IRT) models has been published, which allow estimation of a common latent variable from data derived by different Patient Reported Outcomes (PROs). When using data from different PROs, direct estimation of the latent variable has some advantages over the use of sum score conversion tables. It requires substantial proficiency in the field of psychometrics to fit such models using contemporary IRT software. We developed a web application ( http://www...
October 19, 2016: BMC Medical Research Methodology
Jianfei Yang, Dirk H J Poot, Matthan W A Caan, Tanja Su, Charles B L M Majoie, Lucas J van Vliet, Frans M Vos
PURPOSE: This paper presents and studies a framework for reliable modeling of diffusion MRI using a data-acquisition adaptive prior. METHODS: Automated relevance determination estimates the mean of the posterior distribution of a rank-2 dual tensor model exploiting Jeffreys prior (JARD). This data-acquisition prior is based on the Fisher information matrix and enables the assessment whether two tensors are mandatory to describe the data. The method is compared to Maximum Likelihood Estimation (MLE) of the dual tensor model and to FSL's ball-and-stick approach...
2016: PloS One
Shi-Yong Dong, Zheng-Yu Zuo, Yi-Shan Chao, Kipiro Damas, Bernard Sule
To determine the taxonomic identities and the systematic positions of some collections of Lindsaea sect. Synaphlebium (Lindsaeaceae) from Papua New Guinea, we conducted morphological comparisons and phylogenetic analyses on the whole section. A total of 22 morphological characters were selected and coded for each of all known taxa in L. sect. Synaphlebium, and were analyzed using maximum parsimony. The datasets containing either of or combined two plastid DNA sequences (trnL-trnF spacer and trnH-psbA spacer) of 37 taxa were analyzed using maximum parsimony, maximum likelihood, and Bayesian inference...
2016: PloS One
S Dehkharghani, M Bowen, D C Haussen, T Gleason, A Prater, Q Cai, J Kang, R G Nogueira
BACKGROUND AND PURPOSE: The neuronal substrate is highly sensitive to temperature elevation; however, its impact on the fate of the ischemic penumbra has not been established. We analyzed interactions between temperature and penumbral expansion among successfully reperfused patients with acute ischemic stroke, hypothesizing infarction growth and worse outcomes among patients with fever who achieve full reperfusion. MATERIALS AND METHODS: Data from 129 successfully reperfused (modified TICI 2b/3) patients (mean age, 65 ± 15 years) presenting within 12 hours of onset were examined from a prospectively collected acute ischemic stroke registry...
October 6, 2016: AJNR. American Journal of Neuroradiology
Wei Tong, Tae-Sung Kim, Yong-Jin Park
BACKGROUND: Chloroplast genome variations have been detected, despite its overall conserved structure, which has been valuable for plant population genetics and evolutionary studies. Here, we described chloroplast variation architecture of 383 rice accessions from diverse regions and different ecotypes, in order to mine the rice chloroplast genome variation architecture and phylogenetic. RESULTS: A total of 3677 variations across the chloroplast genome were identified with an average density of 27...
December 2016: Rice
Stephen Shannon, Gavin Breslin, Ben Fitzpatrick, Donncha Hanna, Deirdre Brennan
BACKGROUND: Kidscreen-27 was developed as part of a cross-cultural European Union-funded project to standardise the measurement of children's health-related quality of life. Yet, research has reported mixed evidence for the hypothesised 5-factor model, and no confirmatory factor analysis (CFA) has been conducted on the instrument with children of low socio-economic status (SES) across Ireland (Northern and Republic). METHOD: The data for this study were collected as part of a clustered randomised controlled trial...
October 18, 2016: Quality of Life Research
Bert-Ram Sah, Paul Stolzmann, Gaspar Delso, Scott D Wollenweber, Martin Hüllner, Yahya A Hakami, Marcelo A Queiroz, Felipe de Galiza Barbosa, Gustav K von Schulthess, Carsten Pietsch, Patrick Veit-Haibach
PURPOSE: To investigate the clinical performance of a block sequential regularized expectation maximization (BSREM) penalized likelihood reconstruction algorithm in oncologic PET/computed tomography (CT) studies. METHODS: A total of 410 reconstructions of 41 fluorine-18 fluorodeoxyglucose-PET/CT studies of 41 patients with a total of 2010 lesions were analyzed by two experienced nuclear medicine physicians. Images were reconstructed with BSREM (with four different β values) or ordered subset expectation maximization (OSEM) algorithm with/without time-of-flight (TOF/non-TOF) corrections...
October 18, 2016: Nuclear Medicine Communications
Eun Sook Kim, Robert F Dedrick, Chunhua Cao, John M Ferron
We provide reporting guidelines for multilevel factor analysis (MFA) and use these guidelines to systematically review 72 MFA applications in journals across a range of disciplines (e.g., education, health/nursing, management, and psychology) published between 1994 and 2014. Results are organized in terms of the (a) characteristics of the MFA application (e.g., construct measured), (b) purpose (e.g., measurement validation), (c) data source (e.g., number of cases at Level 1 and Level 2), (d) statistical approach (e...
October 18, 2016: Multivariate Behavioral Research
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