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https://www.readbyqxmd.com/read/28645766/phylogenomic-analysis-supports-multiple-instances-of-polyphyly-in-the-oomycete-peronosporalean-lineage
#1
Marina S Ascunce, Jose C Huguet-Tapia, Almudena Ortiz-Urquiza, Nemat O Keyhani, Edward L Braun, Erica M Goss
The study of biological diversification of oomycetes has been a difficult task for more than a century. Pioneer researchers used morphological characters to describe this heterogeneous group, and physiological and genetic tools expanded knowledge of these microorganisms. However, research on oomycete diversification is limited by conflicting phylogenies. Using whole genomic data from 17 oomycete taxa, we obtained a dataset of 277 core orthologous genes shared among these genomes. Analyses of this dataset resulted in highly congruent and strongly supported estimates of oomycete phylogeny when we used concatenated maximum likelihood and coalescent-based methods; the one important exception was the position of Albugo...
June 20, 2017: Molecular Phylogenetics and Evolution
https://www.readbyqxmd.com/read/28645707/syndemic-factors-mediate-the-relationship-between-sexual-stigma-and-depression-among-sexual-minority-women-and-gender-minorities
#2
Carmen H Logie, Ashley Lacombe-Duncan, Tonia Poteat, Anne C Wagner
INTRODUCTION: Stigma and discrimination contribute to elevated depression risks among sexual minority women (SMW) and gender minority (GM) people who identify as lesbian, bisexual, or queer. Syndemics theory posits that adverse psychosocial outcomes cluster to negatively impact health and mental health outcomes among sexual minorities. We tested whether a syndemic condition composed of low social support, low self-rated health, low self-esteem, and economic insecurity mediated the relationship between sexual stigma and depressive symptoms among SMW/GM...
June 20, 2017: Women's Health Issues: Official Publication of the Jacobs Institute of Women's Health
https://www.readbyqxmd.com/read/28645142/polyphyly-of-arundinoideae-poaceae-and-evolution-of-the-twisted-geniculate-lemma-awn
#3
J K Teisher, M R McKain, B A Schaal, E A Kellogg
Background and Aims: Subfamily Arundinoideae represents one of the last unsolved taxonomic mysteries in the grass family (Poaceae) due to the narrow and remote distributions of many of its 19 morphologically and ecologically heterogeneous genera. Resolving the phylogenetic relationships of these genera could have substantial implications for understanding character evolution in the grasses, for example the twisted geniculate awn - a hygroscopic awn that has been shown to be important in seed germination for some grass species...
June 21, 2017: Annals of Botany
https://www.readbyqxmd.com/read/28645059/association-of-elevated-ambient-temperature-with-death-from-cocaine-overdose
#4
Nathalie Auger, Marianne Bilodeau-Bertrand, Maud Emmanuelle Labesse, Tom Kosatsky
BACKGROUND: Ecologic data suggest that elevated outdoor temperature is correlated with mortality rates from cocaine overdose. Using non-aggregated death records, we studied the association of hot temperatures with risk of death from cocaine overdose. METHODS: We carried out a case-crossover study of all deaths from cocaine or other drug overdose between the months of May and September, from 2000 through 2013 in Quebec, Canada. We used conditional logistic regression to estimate odds ratios (OR) and 95% confidence intervals (CI) for the association between maximum outdoor temperature and death from cocaine or other drug overdose...
June 10, 2017: Drug and Alcohol Dependence
https://www.readbyqxmd.com/read/28644719/shaping-of-reach-to-grasp-kinematics-by-intentions-a-meta-analysis
#5
Ida Egmose, Simo Køppe
When we reach to grasp something, we need to take into account both the properties of the object we are grasping and the intention we have in mind. Previous research has found these constraints to be visible in the reach-to-grasp kinematics, but there is no consensus on which kinematic parameters are the most sensitive. To examine this, a systematic literature search and meta-analyses were performed. The search identified studies assessing how changes in either an object property or a prior intention affect reach-to-grasp kinematics in healthy participants...
June 23, 2017: Journal of Motor Behavior
https://www.readbyqxmd.com/read/28643694/simultaneous-maximum-a-i-posteriori-i-longitudinal-pet-image-reconstruction
#6
Sam Ellis, Andrew J Reader
Positron emission tomography (PET) is frequently used to monitor functional changes that occur over extended time scales, for example in longitudinal oncology PET protocols that include routine clinical follow-up scans to assess the efficacy of a course of treatment. In these contexts PET datasets are currently reconstructed into images using single-dataset reconstruction methods. Inspired by recently proposed joint PET-MR reconstruction methods, we propose to reconstruct longitudinal datasets simultaneously by using a joint penalty term in order to exploit the high degree of similarity between longitudinal images...
June 23, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28642469/tracing-the-epidemic-history-of-hiv-1-crf01_ae-clusters-using-near-complete-genome-sequences
#7
Xingguang Li, Haizhou Liu, Lu Liu, Yi Feng, Marcia L Kalish, Simon Y W Ho, Yiming Shao
Human immunodeficiency virus (HIV) has a number of circulating recombinant forms that are the product of recombination between different HIV subtypes. The first circulating recombinant form of HIV-1 to be identified was CRF01_AE, which originated in Central Africa and is now most prevalent in Southeast and East Asia. In this study, we investigated the timescale, evolutionary history, and population genetics of the HIV-1 CRF01_AE strains primarily responsible for the epidemic in Asia. A further aim of our study was to define and standardize the nomenclature and provide well-characterized reference sequences for the phylogenetic transmission clusters of CRF01_AE...
June 22, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28640619/optimization-and-automation-of-the-construction-of-smooth-free-energy-profiles
#8
Jeremy Schofield
An adaptive procedure is introduced to construct smooth analytical profiles of the free energy along a reaction coordinate using sampled data from multiple biased simulations. The procedure is based upon identifying problematic regions encountered in maximum likelihood estimators of the profile where there are statistically relevant discrepancies between the empirical and parameterized cumulative distribution functions and preferentially improving the construction of the parametric profile in these regions...
June 22, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28640184/a-carrier-estimation-method-based-on-mle-and-kf-for-weak-gnss-signals
#9
Hongyang Zhang, Luping Xu, Bo Yan, Hua Zhang, Liyan Luo
Maximum likelihood estimation (MLE) has been researched for some acquisition and tracking applications of global navigation satellite system (GNSS) receivers and shows high performance. However, all current methods are derived and operated based on the sampling data, which results in a large computation burden. This paper proposes a low-complexity MLE carrier tracking loop for weak GNSS signals which processes the coherent integration results instead of the sampling data. First, the cost function of the MLE of signal parameters such as signal amplitude, carrier phase, and Doppler frequency are used to derive a MLE discriminator function...
June 22, 2017: Sensors
https://www.readbyqxmd.com/read/28639220/emergence-of-rabbit-haemorrhagic-disease-virus-2-in-the-archipelago-of-madeira-portugal-2016-2017
#10
Carina Luísa Carvalho, Sara Silva, Paz Gouveia, Margarida Costa, Elsa Leclerc Duarte, Ana Margarida Henriques, Sílvia Santos Barros, Tiago Luís, Fernanda Ramos, Teresa Fagulha, Miguel Fevereiro, Margarida Dias Duarte
We report the detection of rabbit haemorrhagic disease virus 2 (RHDV2) in the Madeira archipelago, Portugal. Viral circulation was confirmed by RT-qPCR and vp60 sequencing. Epidemiological data revealed the outbreak initiated in October 2016 in Porto Santo affecting wild and domestic rabbits. It was then detected three months later on the island of Madeira. Five haplotypes were identified and a genetic overall similarity of 99.54 to 99.89% was observed between the two viral populations. Unique single nucleotide polymorphisms were recognised in the Madeira archipelago strains, two of which resulting in amino acid substitutions at positions 480 and 570 in the VP60 protein...
June 21, 2017: Virus Genes
https://www.readbyqxmd.com/read/28635549/a-missed-primary-care-appointment-correlates-with-a-subsequent-emergency-department-visit-among-children-with-asthma
#11
Colleen Marie McGovern, Margaret Redmond, Kimberly Arcoleo, David R Stukus
OBJECTIVE: Since the Affordable Care Act's implementation, emergency department (ED) visits have increased. Poor asthma control increases the risk of acute exacerbations and preventable ED visits. The Centers for Medicare and Medicaid Services support the reduction of preventable ED visits to reduce healthcare spending. Implementation of interventions to avoid preventable ED visits has become a priority for many healthcare systems yet little data exist examining children's missed asthma management primary care (PC) appointments and subsequent ED visits...
March 2, 2017: Journal of Asthma: Official Journal of the Association for the Care of Asthma
https://www.readbyqxmd.com/read/28635123/measuring-fitness-heritability-life-history-traits-versus-morphological-traits-in-humans
#12
Alina Gavrus-Ion, Torstein Sjøvold, Miguel Hernández, Rolando González-José, María Esther Esteban Torné, Neus Martínez-Abadías, Mireia Esparza
OBJECTIVES: Traditional interpretation of Fisher's Fundamental Theorem of Natural Selection is that life history traits (LHT), which are closely related with fitness, show lower heritabilities, whereas morphological traits (MT) are less related with fitness and they are expected to show higher heritabilities. In humans, although few studies have examined the heritability of LHT and MT, none of them have analyzed the same sample for comparative purposes. Here we assessed, for the first time, the heritability, additive genetic variance (VA ), residual variance (VR ) and coefficient of genetic additive variation (CVA ) values of LHT and MT in a singular collection of identified skulls with associated demographic records from Hallstatt (Austria)...
June 21, 2017: American Journal of Physical Anthropology
https://www.readbyqxmd.com/read/28632933/patient-characteristics-associated-with-a-successful-response-to-nurse-led-care-programs-targeting-the-oldest-old-a-comparison-of-two-rcts
#13
Nienke Bleijenberg, Lorenz Imhof, Romy Mahrer-Imhof, Margaret I Wallhagen, Niek J de Wit, Marieke J Schuurmans
BACKGROUND: To improve the effectiveness of community-based care programs, especially those targeting the oldest-old population (80+), data are needed that elucidate those factors associated with a successful response to the intervention. Two comparable nurse-led care programs have been evaluated in two large randomized controlled trials (RCTs), one in Switzerland and one in the Netherlands. AIMS: To identify common patient characteristics that are related to a successful response to proactive nurse-led care, we explored if and to what extent, identical factors were present in both study populations...
June 2017: Worldviews on Evidence-based Nursing
https://www.readbyqxmd.com/read/28631295/an-em-algorithm-for-nonparametric-estimation-of-the-cumulative-incidence-function-from-repeated-imperfect-test-results
#14
Birgit I Witte, Johannes Berkhof, Marianne A Jonker
In screening and surveillance studies, event times are interval censored. Besides, screening tests are imperfect so that the interval at which an event takes place may be uncertain. We describe an expectation-maximization algorithm to find the nonparametric maximum likelihood estimator of the cumulative incidence function of an event based on screening test data. Our algorithm has a closed-form solution for the combined expectation and maximization step and is computationally undemanding. A simulation study indicated that the bias of the estimator tends to zero for large sample size, and its mean squared error is in general lower than the mean squared error of the estimator that assumes the screening test is perfect...
June 20, 2017: Statistics in Medicine
https://www.readbyqxmd.com/read/28630602/comparing-the-performance-of-improved-classify-analyze-approaches-for-distal-outcomes-in-latent-profile-analysis
#15
John J Dziak, Bethany C Bray, Jieting Zhang, Minqiang Zhang, Stephanie T Lanza
Several approaches are available for estimating the relationship of latent class membership to distal outcomes in latent profile analysis (LPA). A three-step approach is commonly used, but has problems with estimation bias and confidence interval coverage. Proposed improvements include the correction method of Bolck, Croon, and Hagenaars (BCH; 2004), Vermunt's (2010) maximum likelihood (ML) approach, and the inclusive three-step approach of Bray, Lanza, & Tan (2015). These methods have been studied in the related case of latent class analysis (LCA) with categorical indicators, but not as well studied for LPA with continuous indicators...
October 2016: Methodology: European Journal of Research Methods for the Behavioral & Social Sciences
https://www.readbyqxmd.com/read/28630234/multiparametric-model-for-penumbral-flow-prediction-in-acute-stroke
#16
Michelle Livne, Tabea Kossen, Vince I Madai, Olivier Zaro-Weber, Walter Moeller-Hartmann, Kim Mouridsen, Wolf-Dieter Heiss, Jan Sobesky
BACKGROUND AND PURPOSE: Identification of salvageable penumbra tissue by dynamic susceptibility contrast magnetic resonance imaging is a valuable tool for acute stroke patient stratification for treatment. However, prior studies have not attempted to combine the different perfusion maps into a predictive model. In this study, we established a multiparametric perfusion imaging model and cross-validated it using positron emission tomography perfusion for detection of penumbral flow. METHODS: In a retrospective analysis of 17 subacute stroke patients with consecutive magnetic resonance imaging and H2O15 positron emission tomography scans, perfusion maps of cerebral blood flow, cerebral blood volume, mean transit time, time-to-maximum, and time-to-peak were constructed and combined using a generalized linear model (GLM)...
June 19, 2017: Stroke; a Journal of Cerebral Circulation
https://www.readbyqxmd.com/read/28624874/reliable-molecular-differentiation-of-trichuris-ovis-and-trichuris-discolor-from-sheep-ovis-orientalis-aries-and-roe-deer-capreolus-capreolus-and-morphological-characterisation-of-their-females-morphology-does-not-work-sufficiently
#17
Pavel Vejl, Stanislava Nechybová, Pavla Peřinková, Martina Melounová, Vladimíra Sedláková, Jakub Vašek, Daniela Čílová, Kateřina Rylková, Ivana Jankovská, Jaroslav Vadlejch, Iva Langrová
The main aim of the study was to evaluate associations between morphological variability of Trichuris females from sheep and roe deer and their rDNA polymorphism in whipworm populations from the Czech Republic. The results introduced the use of new molecular markers based on the internal transcribed spacer (ITS)1-5.8S RNA-ITS2 region polymorphisms, as useful tools for the unambiguous differentiation of congeners Trichuris ovis and Trichuris discolor. These markers revealed both parasites in roe deer and in sheep; however, T...
June 17, 2017: Parasitology Research
https://www.readbyqxmd.com/read/28624516/pleistocene-range-shifts-refugia-and-the-origin-of-widespread-species-in-western-palaearctic-water-beetles
#18
David García-Vázquez, David T Bilton, Garth N Foster, I Ribera
Quaternary glacial cycles drove major shifts in both the extent and location of the geographical ranges of many organisms. During glacial maxima, large areas of central and northern Europe were inhospitable to temperate species, and these areas are generally assumed to have been recolonized during interglacials by range expansions from Mediterranean refugia. An alternative is that this recolonization was from non-Mediterranean refugia, in central Europe or western Asia, but data on the origin of widespread central and north European species remain fragmentary, especially for insects...
June 15, 2017: Molecular Phylogenetics and Evolution
https://www.readbyqxmd.com/read/28623959/the-impact-of-wolbachia-infection-on-the-rate-of-vertical-transmission-of-dengue-virus-in-brazilian-aedes-aegypti
#19
Etiene Casagrande Pacidônio, Eric Pearce Caragata, Debora Magalhães Alves, João Trindade Marques, Luciano Andrade Moreira
BACKGROUND: Wolbachia pipientis is a common endosymbiotic bacterium of arthropods that strongly inhibits dengue virus (DENV) infection and transmission in the primary vector, the mosquito Aedes aegypti. For that reason, Wolbachia-infected Ae. aegypti are currently being released into the field as part of a novel strategy to reduce DENV transmission. However, there is evidence that DENV can be transmitted vertically from mother to progeny, and this may help the virus persist in nature in the absence of regular human transmission...
June 17, 2017: Parasites & Vectors
https://www.readbyqxmd.com/read/28618610/estimating-higher-order-structure-functions-from-geophysical-turbulence-time-series-confronting-the-curse-of-the-limited-sample-size
#20
Adam W DeMarco, Sukanta Basu
Utilizing synthetically generated random variates and laboratory measurements, we document the inherent limitations of the conventional structure function approach in limited sample size settings. We demonstrate that an alternative approach, based on the principle of maximum likelihood, can provide nearly unbiased structure function estimates with far less uncertainty under such unfavorable conditions. The superiority of this approach over the conventional approach does not diminish even in the case of strongly correlated samples...
May 2017: Physical Review. E
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