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https://www.readbyqxmd.com/read/28645065/cross-validation-of-short-forms-of-the-screener-and-opioid-assessment-for-patients-with-pain-revised-soapp-r
#1
Matthew D Finkelman, Robert N Jamison, Ronald J Kulich, Stephen F Butler, William C Jackson, Niels Smits, Scott G Weiner
BACKGROUND: The Screener and Opioid Assessment for Patients with Pain-Revised (SOAPP-R) is a 24-item assessment designed to assist in the prediction of aberrant drug-related behavior (ADB) among patients with chronic pain. Recent work has created shorter versions of the SOAPP-R, including a static 12-item short form and two computer-based methods (curtailment and stochastic curtailment) that monitor assessments in progress. The purpose of this study was to cross-validate these shorter versions in two new populations...
June 13, 2017: Drug and Alcohol Dependence
https://www.readbyqxmd.com/read/28644841/low-dimensional-spike-rate-models-derived-from-networks-of-adaptive-integrate-and-fire-neurons-comparison-and-implementation
#2
Moritz Augustin, Josef Ladenbauer, Fabian Baumann, Klaus Obermayer
The spiking activity of single neurons can be well described by a nonlinear integrate-and-fire model that includes somatic adaptation. When exposed to fluctuating inputs sparsely coupled populations of these model neurons exhibit stochastic collective dynamics that can be effectively characterized using the Fokker-Planck equation. This approach, however, leads to a model with an infinite-dimensional state space and non-standard boundary conditions. Here we derive from that description four simple models for the spike rate dynamics in terms of low-dimensional ordinary differential equations using two different reduction techniques: one uses the spectral decomposition of the Fokker-Planck operator, the other is based on a cascade of two linear filters and a nonlinearity, which are determined from the Fokker-Planck equation and semi-analytically approximated...
June 23, 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28644830/optimal-chemotactic-responses-in-stochastic-environments
#3
Martin Godány, Bhavin S Khatri, Richard A Goldstein
Although the "adaptive" strategy used by Escherichia coli has dominated our understanding of bacterial chemotaxis, the environmental conditions under which this strategy emerged is still poorly understood. In this work, we study the performance of various chemotactic strategies under a range of stochastic time- and space-varying attractant distributions in silico. We describe a novel "speculator" response in which the bacterium compare the current attractant concentration to the long-term average; if it is higher then they tumble persistently, while if it is lower than the average, bacteria swim away in search of more favorable conditions...
2017: PloS One
https://www.readbyqxmd.com/read/28644671/spin-pumping-and-torque-statistics-in-the-quantum-noise-limit
#4
P Virtanen, T T Heikkilä
We analyze the statistics of charge and energy currents and spin torque in a metallic nanomagnet coupled to a large magnetic metal via a tunnel contact. We derive a Keldysh action for the tunnel barrier, describing the stochastic currents in the presence of a magnetization precessing with the rate Ω. In contrast to some earlier approaches, our result is valid for an arbitrary ratio of ℏΩ/k_{B}T. We illustrate the use of the action by deriving spintronic fluctuation relations, the quantum limit of pumped current noise, and consider the fluctuations in two specific cases: the situation with a stable precession of magnetization driven by spin transfer torque, and the torque-induced switching between the minima of a magnetic anisotropy...
June 9, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28642991/extensive-overlap-of-tropical-rainforest-bacterial-endophytes-between-soil-plant-parts-and-plant-species
#5
Emmanuel Haruna, Noraziah M Zin, Dorsaf Kerfahi, Jonathan M Adams
The extent to which distinct bacterial endophyte communities occur between different plant organs and species is poorly known and has implications for bioprospecting efforts. Using the V3 region of the bacterial 16S ribosomal RNA (rRNA) gene, we investigated the diversity patterns of bacterial endophyte communities of three rainforest plant species, comparing leaf, stem, and root endophytes plus rhizosphere soil community. There was extensive overlap in bacterial communities between plant organs, between replicate plants of the same species, between plant species, and between plant organ and rhizosphere soil, with no consistent clustering by compartment or host plant species...
June 22, 2017: Microbial Ecology
https://www.readbyqxmd.com/read/28642735/functional-and-compositional-stability-of-bacterial-metacommunities-in-response-to-salinity-changes
#6
Mercè Berga, Yinghua Zha, Anna J Székely, Silke Langenheder
Disturbances and environmental change are important factors determining the diversity, composition, and functioning of communities. However, knowledge about how natural bacterial communities are affected by such perturbations is still sparse. We performed a whole ecosystem manipulation experiment with freshwater rock pools where we applied salinity disturbances of different intensities. The aim was to test how the compositional and functional resistance and resilience of bacterial communities, alpha- and beta-diversity and the relative importance of stochastic and deterministic community assembly processes changed along a disturbance intensity gradient...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28642686/transcranial-random-noise-stimulation-trns-shapes-the-processing-of-rapidly-changing-auditory-information
#7
Katharina S Rufener, Philipp Ruhnau, Hans-Jochen Heinze, Tino Zaehle
Neural oscillations in the gamma range are the dominant rhythmic activation pattern in the human auditory cortex. These gamma oscillations are functionally relevant for the processing of rapidly changing acoustic information in both speech and non-speech sounds. Accordingly, there is a tight link between the temporal resolution ability of the auditory system and inherent neural gamma oscillations. Transcranial random noise stimulation (tRNS) has been demonstrated to specifically increase gamma oscillation in the human auditory cortex...
2017: Frontiers in Cellular Neuroscience
https://www.readbyqxmd.com/read/28642270/heritable-micro-environmental-variance-covaries-with-fitness-in-an-outbred-population-of-drosophila-serrata
#8
Jacqueline L Sztepanacz, Katrina McGuigan, Mark W Blows
The genetic basis of stochastic variation within a defined environment, and the consequences of such micro-environmental variance for fitness are poorly understood. Using a multigenerational breeding design in Drosophila serrata, we demonstrated that the micro-environmental variance in a set of morphological wing traits in a randomly mating population had significant additive genetic variance in most single wing traits. Although heritability was generally low (< 1%), coefficients of additive genetic variance were of a magnitude typical of other morphological traits, indicating that the micro-environmental variance is an evolvable trait...
June 22, 2017: Genetics
https://www.readbyqxmd.com/read/28641438/erratum-stochastic-multi-reference-perturbation-theory-with-application-to-the-linearized-coupled-cluster-method-j-chem-phys-146-044107-2017
#9
Guillaume Jeanmairet, Sandeep Sharma, Ali Alavi
No abstract text is available yet for this article.
June 21, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28641269/a-model-based-tool-for-the-analysis-and-design-of-gene-regulatory-network
#10
Liliana Ironi, Ettore Lanzarone
Computational and mathematical models have significantly contributed to the rapid progress in the study of gene regulatory networks (GRN), but researchers still lack a reliable model-based framework for computer-aided analysis and design. Such tool should both reveal the relation between network structure and dynamics and find parameter values and/or constraints that enable the simulated dynamics to reproduce specific behaviors. This paper addresses these issues and proposes a computational framework that facilitates network analysis or design...
June 19, 2017: IEEE/ACM Transactions on Computational Biology and Bioinformatics
https://www.readbyqxmd.com/read/28640895/the-interplay-of-climate-intervention-and-imported-cases-as-determinants-of-the-2014-dengue-outbreak-in-guangzhou
#11
Qu Cheng, Qinlong Jing, Robert C Spear, John M Marshall, Zhicong Yang, Peng Gong
Dengue is a fast spreading mosquito-borne disease that affects more than half of the population worldwide. An unprecedented outbreak happened in Guangzhou, China in 2014, which contributed 52 percent of all dengue cases that occurred in mainland China between 1990 and 2015. Our previous analysis, based on a deterministic model, concluded that the early timing of the first imported case that triggered local transmission and the excessive rainfall thereafter were the most important determinants of the large final epidemic size in 2014...
June 22, 2017: PLoS Neglected Tropical Diseases
https://www.readbyqxmd.com/read/28640883/an-artificial-emg-generation-model-based-on-signal-dependent-noise-and-related-application-to-motion-classification
#12
Akira Furui, Hideaki Hayashi, Go Nakamura, Takaaki Chin, Toshio Tsuji
This paper proposes an artificial electromyogram (EMG) signal generation model based on signal-dependent noise, which has been ignored in existing methods, by introducing the stochastic construction of the EMG signals. In the proposed model, an EMG signal variance value is first generated from a probability distribution with a shape determined by a commanded muscle force and signal-dependent noise. Artificial EMG signals are then generated from the associated Gaussian distribution with a zero mean and the generated variance...
2017: PloS One
https://www.readbyqxmd.com/read/28640391/selective-sweeps-of-mitochondrial-dna-can-drive-the-evolution-of-uniparental-inheritance
#13
Joshua R Christie, Madeleine Beekman
While the uniparental (or maternal) inheritance of mitochondrial DNA (mtDNA) is widespread, the reasons for its evolution remain unclear. Two main hypotheses have been proposed: selection against individuals containing different mtDNAs (heteroplasmy) and selection against "selfish" mtDNA mutations. Recently, uniparental inheritance was shown to promote adaptive evolution in mtDNA, potentially providing a third hypothesis for its evolution. Here we explore this hypothesis theoretically and ask if the accumulation of beneficial mutations provides a sufficient fitness advantage for uniparental inheritance to invade a population in which mtDNA is inherited biparentally...
June 22, 2017: Evolution; International Journal of Organic Evolution
https://www.readbyqxmd.com/read/28639869/economic-burden-of-inpatient-admission-of-ankle-fractures
#14
Justin D Stull, Suneel B Bhat, Justin M Kane, Steven M Raikin
BACKGROUND: Ankle fractures are among the most prevalent traumatic orthopaedic injuries. A large proportion of patients sustaining operative ankle fractures are admitted directly from the emergency department prior to operative management. In the authors' experience, however, many closed ankle injuries may be safely and effectively managed on an outpatient basis. The aim of this study was to characterize the economic impact of routine inpatient admission of ankle fractures. METHODS: A retrospective review of all outpatient ankle fracture surgery performed by a single foot and ankle fellowship-trained surgeon at a tertiary level academic center in 2012 was conducted to identify any patients requiring postoperative inpatient admission...
June 1, 2017: Foot & Ankle International
https://www.readbyqxmd.com/read/28638377/a-novel-bromodomain-inhibitor-reverses-hiv-1-latency-through-specific-binding-with-brd4-to-promote-tat-and-p-tefb-association
#15
Huachao Huang, Shuai Liu, Maxime Jean, Sydney Simpson, He Huang, Mark Merkley, Tsuyoshi Hayashi, Weili Kong, Irene Rodríguez-Sánchez, Xiaofeng Zhang, Hailemichael O Yosief, Hongyu Miao, Jianwen Que, James J Kobie, James Bradner, Netty G Santoso, Wei Zhang, Jian Zhu
While combinatory antiretroviral therapy (cART) can effectively reduce HIV-1 viremia, it cannot eliminate HIV-1 infection. In the presence of cART, viral reservoirs remain latent, impeding the cure of HIV-1/AIDS. Recently, latency-reversing agents (LRAs) have been developed with the intent of purging latent HIV-1, providing an intriguing strategy for the eradication of the residual viral reservoirs. Our earlier studies show that the first-generation, methyl-triazolo bromodomain, and extra-terminal domain inhibitor (BETi), JQ1, facilitates the reversal of HIV-1 latency...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28638324/stochastic-signatures-of-involuntary-head-micro-movements-can-be-used-to-classify-females-of-abide-into-different-subtypes-of-neurodevelopmental-disorders
#16
Elizabeth B Torres, Sejal Mistry, Carla Caballero, Caroline P Whyatt
Background: The approximate 5:1 male to female ratio in clinical detection of Autism Spectrum Disorder (ASD) prevents research from characterizing the female phenotype. Current open access repositories [such as those in the Autism Brain Imaging Data Exchange (ABIDE I-II)] contain large numbers of females to help begin providing a new characterization of females on the autistic spectrum. Here we introduce new methods to integrate data in a scale-free manner from continuous biophysical rhythms of the nervous systems and discrete (ordinal) observational scores...
2017: Frontiers in Integrative Neuroscience
https://www.readbyqxmd.com/read/28638320/membrane-fusion-involved-in-neurotransmission-glimpse-from-electron-microscope-and-molecular-simulation
#17
REVIEW
Zhiwei Yang, Lu Gou, Shuyu Chen, Na Li, Shengli Zhang, Lei Zhang
Membrane fusion is one of the most fundamental physiological processes in eukaryotes for triggering the fusion of lipid and content, as well as the neurotransmission. However, the architecture features of neurotransmitter release machinery and interdependent mechanism of synaptic membrane fusion have not been extensively studied. This review article expounds the neuronal membrane fusion processes, discusses the fundamental steps in all fusion reactions (membrane aggregation, membrane association, lipid rearrangement and lipid and content mixing) and the probable mechanism coupling to the delivery of neurotransmitters...
2017: Frontiers in Molecular Neuroscience
https://www.readbyqxmd.com/read/28638071/emergent-stochastic-oscillations-and-signal-detection-in-tree-networks-of-excitable-elements
#18
Justus Kromer, Ali Khaledi-Nasab, Lutz Schimansky-Geier, Alexander B Neiman
We study the stochastic dynamics of strongly-coupled excitable elements on a tree network. The peripheral nodes receive independent random inputs which may induce large spiking events propagating through the branches of the tree and leading to global coherent oscillations in the network. This scenario may be relevant to action potential generation in certain sensory neurons, which possess myelinated distal dendritic tree-like arbors with excitable nodes of Ranvier at peripheral and branching nodes and exhibit noisy periodic sequences of action potentials...
June 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28638046/a-note-on-the-stationary-distribution-of-stochastic-seir-epidemic-model-with-saturated-incidence-rate
#19
Qixing Han, Liang Chen, Daqing Jiang
The stochastic SEIR infectious diseases model with saturated incidence rate is studied in this paper. By constructing appropriate Lyapunov functions, we show that there is a stationary distribution for the system and the ergodicity holds provided [Formula: see text] > 1. In particular, we improve the results obtained by previous studies greatly, condition in our Theorem is more concise and elegant.
June 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28637916/model-based-analysis-of-an-outbreak-of-bubonic-plague-in-cairo-in-1801
#20
Xavier Didelot, Lilith K Whittles, Ian Hall
Bubonic plague has caused three deadly pandemics in human history: from the mid-sixth to mid-eighth century, from the mid-fourteenth to the mid-eighteenth century and from the end of the nineteenth until the mid-twentieth century. Between the second and the third pandemics, plague was causing sporadic outbreaks in only a few countries in the Middle East, including Egypt. Little is known about this historical phase of plague, even though it represents the temporal, geographical and phylogenetic transition between the second and third pandemics...
June 2017: Journal of the Royal Society, Interface
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