Read by QxMD icon Read

State dependent model

Mengfei Fan, Zhiguo Zeng, Enrico Zio, Rui Kang, Ying Chen
In this paper, we develop a framework to model and analyze systems that are subject to dependent, competing degradation processes and random shocks. The degradation processes are described by stochastic differential equations, whereas transitions between the system discrete states are triggered by random shocks. The modeling is, then, based on Stochastic Hybrid Systems (SHS), whose state space is comprised of a continuous state determined by stochastic differential equations and a discrete state driven by stochastic transitions and reset maps...
2017: PloS One
Joon Sang Kang, Ming Ke, Yongjie Hu
Two-dimensional van der Waals materials have shown novel fundamental properties and promise for wide applications. Here, we reported, for the first time, an experimental demonstration of the in-situ characterization and control of the anisotropic thermal conductivity of black phosphorus. We develop a novel platform based on lithium ion batteries that integrates ultrafast optical spectroscopy and electrochemical control to investigate the interactions between lithium ions and the lattices of the black phosphorus electrode...
February 23, 2017: Nano Letters
Kazuki Matsui, Yasuhiro Tsume, Susumu Takeuchi, Amanda Searls, Gordon L Amidon
Weakly basic drugs exhibit a pH-dependent dissolution profile in the gastrointestinal (GI) tract, making it difficult to predict their oral absorption profile. The aim of this study was to investigate the utility of the Gastrointestinal Simulator (GIS), a novel in vivo predictive dissolution (iPD) methodology, in predicting the in vivo behavior of the weakly basic drug, dipyridamole, when coupled with in silico analysis. The GIS is a multi-compartmental dissolution apparatus, which represents physiological gastric emptying in the fasted state...
February 23, 2017: Molecular Pharmaceutics
Pin-Hao Sher, Juen-Kai Wang
Applications of quantum dot (QD) are often obstructed by its associated surface electronic states that quench photoluminescence (PL) and hinder charge transport. Their origins are still largely stymied owing to lacking means to regulate their presence. Dispersing PbS QDs in toluene, we show that varying solvent temperature offers an opportunity to modulate their surface electronic state. A comprehensive energy-transfer model explains all anomalous temperature-dependent behaviors of absorption and PL, explicitly revealing PL quenching dynamics of isolated QDs due to induced surface state by imposed solvent stress to their surface ligands...
February 23, 2017: Nanotechnology
Jialu Liu, Xiang Ren, Jingbo Shang, Taylor Cassidy, Clare R Voss, Jiawei Han
Many text mining approaches adopt bag-of-words or n-grams models to represent documents. Looking beyond just the words, i.e., the explicit surface forms, in a document can improve a computer's understanding of text. Being aware of this, researchers have proposed concept-based models that rely on a human-curated knowledge base to incorporate other related concepts in the document representation. But these methods are not desirable when applied to vertical domains (e.g., literature, enterprise, etc.) due to low coverage of in-domain concepts in the general knowledge base and interference from out-of-domain concepts...
April 2016: Proceedings of the International World-Wide Web Conference
Jasper Boschmans, Filip Lemière, Frank Sobott
The use of traveling wave ion mobility mass spectrometry (TWIMS) is evaluated in conjunction with, and as a possible alternative to, conventional LC-MS(/MS) methods for the separation and characterization of drug-like compounds and metabolites. As a model system we use an in vitro incubation mixture of the chemotherapeutic agent melphalan, which results in more than ten closely related hydrolysis products and chain-like oligomers. Ion mobility as a filtering tool results in the separation of ions of interest from interfering ions, based on charge state and shape/size...
February 14, 2017: Journal of Chromatography. A
Han Luo, Marat Kulakhmetov, Alina Alexeenko
Quasi-classical trajectory (QCT) calculations are used in this work to calculate state-specific N2(X(1)Σ)+O((3)P)→2N((4)S)+O((3)P) dissociation and N2(X(1)Σ)+O((3)P)→NO(X(2)Π)+N((4)S) exchange cross sections and rates based on the 1(3)A″ and 1(3)A' ab initio potential energy surface by Gamallo et al. [J. Chem. Phys. 119, 2545-2556 (2003)]. The calculations consider translational energies up to 23 eV and temperatures between 1000 K and 20 000 K. Vibrational favoring is observed for dissociation reaction at the whole range of collision energies and for exchange reaction around the dissociation limit...
February 21, 2017: Journal of Chemical Physics
Qiuju Zheng, John C Mauro
Glasses are nonequilibrium materials that continuously relax toward the metastable supercooled liquid state. As such, the properties of a glass depend on both its composition and thermal history. When an initially cooled glass is subjected to additional thermal cycles, relaxation during the heat treatment is accelerated, leading to changes in the macroscopic properties of the glass. This relaxation behavior is intrinsic to the glassy state and of critical interest to the high-tech glass industry. In many practical cases, the magnitude of the relaxation is less important than the variability of the relaxation effects due to slight variations in the thermal history experienced by the glass...
February 21, 2017: Journal of Chemical Physics
Shuai Zhang, Kevin P Driver, François Soubiran, Burkhard Militzer
As one of the simple alkali metals, sodium has been of fundamental interest for shock physics experiments, but knowledge of its equation of state (EOS) in hot, dense regimes is not well known. By combining path integral Monte Carlo (PIMC) results for partially ionized states [B. Militzer and K. P. Driver, Phys. Rev. Lett. 115, 176403 (2015)] at high temperatures and density functional theory molecular dynamics (DFT-MD) results at lower temperatures, we have constructed a coherent equation of state for sodium over a wide density-temperature range of 1...
February 21, 2017: Journal of Chemical Physics
Yuncheng Du, Dongping Du, Yuncheng Du, Dongping Du, Dongping Du, Yuncheng Du
Cardiac potassium (K+) channel plays an important role in cardiac electrical signaling. Mathematical models have been widely used to investigate the effects of K+ channels on cardiac functions. However, the model of K+ channel involves parametric uncertainties, which can be induced by fitting the model's parameters that best capture experimental data. Since the prediction of cardiac functions are highly parameter-dependent, it is critical to quantify the influence of parametric uncertainty on the model responses to provide the more reliable predictions...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
Behnaz Jarrahi, Dante Mantini, Behnaz Jarrahi, Dante Mantini, Behnaz Jarrahi, Dante Mantini
Advanced multivariate analyses of functional magnetic resonance imaging (fMRI) data based on blood oxygen level-dependent (BOLD) contras have revealed that the human brain organizes its activities into multiple intrinsic connectivity networks (ICNs). Several fMRI studies have evaluated the modulations of these networks during different cognitive or emotional tasks using blind source separation techniques particularly the independent component analysis (ICA). In this exploratory study, we applied ICA methodology to examine ICN modulations under different interoceptive conditions...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
Gregg Johns, Evelyn Morin, Keyvan Hashtrudi-Zaad, Gregg Johns, Evelyn Morin, Keyvan Hashtrudi-Zaad, Keyvan Hashtrudi-Zaad, Gregg Johns, Evelyn Morin
There is a discontinuity in published electromechanical delays (EMD) in upper-limb muscles and the state-of-the-art in modelling end-point force from electromyographic signals collected from one or more muscles. Published values are typically in the range of 10 to 30ms, depending on the nature of the contraction. In published literature where the EMG-force relationship is modelled, generally a delay of 100ms or more is induced during linear enveloping to match the EMD. The implications of EMD on end-point force prediction were considered using inter-session end-point force modelling with a support-vector-regression model...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
J Hagenah, E Werrmann, M Scharfschwerdt, F Ernst, C Metzner, J Hagenah, E Werrmann, M Scharfschwerdt, F Ernst, C Metzner, C Metzner, E Werrmann, J Hagenah, F Ernst, M Scharfschwerdt
Valve-sparing aortic root reconstruction is an up- and-coming approach for patients suffering from aortic valve insufficiencies which promises to significantly reduce complications. However, the success of the treatment strongly depends on the challenging task of choosing the correct size of the prosthesis, for which, up to now, surgeons solely have to rely on their experience. Here, we present a novel machine learning based approach, which might make it possible to predict the size of the prosthesis from pre-operatively acquired ultrasound images...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
I Loram, R Cunningham, J Zenzeri, H Gollee, I Loram, R Cunningham, J Zenzeri, H Gollee, J Zenzeri, R Cunningham, I Loram, H Gollee
Multivariable intermittent control (MIC) combines stability with flexibility in the control of unstable systems. Using an underlying continuous-time optimal control design, MIC uses models of the physical system to generate multivariate open-loop control signals between samples of the observed state. Using accurate model values of physical system parameters, stability of the closed loop system is not dependent upon sample interval. Here we consider the sensitivity of MIC to inaccurate model values of system parameters...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
Xiya Lu, Victor Ovchinnikov, Darren Demapan, Daniel Roston, Qiang Cui
The mechanism of ATP hydrolysis in the myosin motor domain is analyzed using a combination of DFTB3/CHARMM simulations and enhanced sampling techniques. The motor domain is modeled in the pre-powerstroke state, in the post-rigor state, and a hybrid model based on the post-rigor state with a closed nucleotide-binding pocket. The ATP hydrolysis activity is found to depend on the positioning of nearby water molecules, and a network of polar residues facilitates proton transfer and charge redistribution during hydrolysis...
February 22, 2017: Biochemistry
Susmita Ghosh, Abhijit Chatterjee, Swati Bhattacharya
This Letter demonstrates that using time-dependent Markov state models (TD-MSMs) one can obtain molecular-scale insights into force-extension curves for a variety of stretching experiments. A master-MSM constructed at a reference extension using a handful of molecular dynamics calculations forms the basis for generating the required TD-MSM. Changes in the network topology upon stretching is related through a thermodynamic quantity termed the mechanical disposition. Proof-of-principle is provided using a stretched alanine decapeptide under a time-varying pulling force...
February 22, 2017: Journal of Chemical Theory and Computation
Mangyu Choe, Young-Ha Park, Chang-Ro Lee, Yeon-Ran Kim, Yeong-Jae Seok
Preferential sugar utilization is a widespread phenomenon in biological systems. Glucose is usually the most preferred carbon source in various organisms, especially in bacteria where it is taken up via the phosphoenolpyruvate:sugar phosphotransferase system (PTS). The currently proposed model for glucose preference over non-PTS sugars in enteric bacteria including E. coli is strictly dependent on the phosphorylation state of the glucose-specific PTS component, enzyme IIA(Glc) (EIIA(Glc)). However, the mechanism of the preference among PTS sugars is largely unknown in Gram-negative bacteria...
February 22, 2017: Scientific Reports
Patrick D Brophy
Telehealth in Pediatric Medicine presents many of the same benefits and challenges noted in adult-based medicine. In terms of health care delivery, the promise of improving access and reducing costs using telehealth in Pediatrics, particularly chronic care, is high. The ability to address clinician shortages and provide remote guidance for chronic care pathways from pediatric subspecialists to rural-based referring physicians is a developing model that represents a sustainable and cost-effective strategy to improve pediatric care...
January 2017: Advances in Chronic Kidney Disease
Sunghee Oh, Seongho Song
In gene expression profile, data analysis pipeline is categorized into four levels, major downstream tasks, i.e., (1) identification of differential expression; (2) clustering co-expression patterns; (3) classification of subtypes of samples; and (4) detection of genetic regulatory networks, are performed posterior to preprocessing procedure such as normalization techniques. To be more specific, temporal dynamic gene expression data has its inherent feature, namely, two neighboring time points (previous and current state) are highly correlated with each other, compared to static expression data which samples are assumed as independent individuals...
2017: Methods in Molecular Biology
Kenji Okamoto
Structural dynamics of biomolecules, such as proteins, plays essential roles in many biological phenomena at molecular level. It is crucial to understand such dynamics in recent biology. The single-molecule Förster resonance energy transfer (smFRET) measurement is one of few methods that enable us to observe structural changes of biomolecules in realtime. Time series data of smFRET, however, typically contains significant fluctuation, making analysis difficult. On the other hand, one can often assume a Markov process behind such data so that the hidden Markov model (HMM) can be used to reproduce a state transition trajectory (STT)...
2017: Methods in Molecular Biology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"