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Maltsev Victor A VA Laboratory of Cardiovascular Science, Intramural Research Program, National Institute on Aging, NIH, - - 2014
Cardiac pacemaking is a complex phenomenon that is still not completely understood. Together with experimental studies, numerical modeling has been traditionally used to acquire mechanistic insights in this research area. This review summarizes the present state of numerical modeling of the cardiac pacemaker, including approaches to resolve present paradoxes and ...
Lu Bing-Qiang BQ State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 - - 2014
A highly flexible and nonflammable inorganic hydroxyapatite (HAP) paper made from HAP ultralong nanowires is reported. The paper can be used for printing and writing and is promising for the permanent and safe storage of information, such as archives and important documents. The HAP paper is also an excellent and ...
Yu Ruiyun R Software College, Northeastern University, No. 11, Lane 3, Wenhua Road, Heping District, Shenyang 100819, China. - - 2014
The ubiquity of mobile devices brings forth a sensing paradigm, participatory sensing, to collect and interpret sensory information from the environment. Participants join in multifarious sensing tasks and share their data. The sensing result can be obtained in light of shared data. It is not uncommon that some corrupted data ...
Vu-Van Hiep H The School of Electrical Engineering, University of Ulsan, San 29, Muger 2-dong, Ulsan 680-749, Republic of - - 2014
Cognitive radio (CR) is a promising technology for improving usage of frequency band. Cognitive radio users (CUs) are allowed to use the bands without interference in operation of licensed users. Reliable sensing information about status of licensed band is a prerequirement for CR network. Cooperative spectrum sensing (CSS) is able ...
Yaniv Yael Y Laboratory of Cardiovascular Science, Intramural Research Program, National Institute on Aging - National Institutes of Health Baltimore, MD, USA ; Department of Biomedical Engineering, Technion - Israel Institute of Technology Haifa, - - 2014
Sinoatrial node (SAN) is the primary heart pacemaker which initiates each heartbeat under normal conditions. Numerous experimental data have demonstrated that Ca(2+-) and CaMKII-dependent processes are crucially important for regulation of SAN cells. However, specific mechanisms of this regulation and their relative contribution to pacemaker function remain mainly unknown. Our ...
Chavan Swapnil S Bioorganic & Biophysical Chemistry Laboratory, Linnaeus University Centre for Biomaterials Chemistry and Department of Chemistry & Biomedical Sciences, Linnaeus University, Kalmar SE-391 82, Sweden. - - 2014
A series of 436 Munro database chemicals were studied with respect to their corresponding experimental LD50 values to investigate the possibility of establishing a global QSAR model for acute toxicity. Dragon molecular descriptors were used for the QSAR model development and genetic algorithms were used to select descriptors better correlated ...
Woller Aurore A Unité de Chronobiologie Théorique, CP 231, Faculté des Sciences, Université Libre de Bruxelles, Bruxelles, - - 2013
The circadian timekeeping system appears more complex in birds than in mammals. In mammals, the main pacemaker is centralized in the suprachiasmatic nuclei, whereas in birds, the pacemaker involves the interplay between the pineal and hypothalamic oscillators. In order to investigate the consequence of this complex mechanism, we propose here ...
Costa Maria J MJ Warwick Systems Biology Centre, University of Warwick, Coventry CV4 7AL, UK,. - - 2013
Estimation of the period length of time-course data from cyclical biological processes, such as those driven by the circadian pacemaker, is crucial for inferring the properties of the biological clock found in many living organisms. We propose a methodology for period estimation based on spectrum resampling (SR) techniques. Simulation studies ...
Maltsev Victor A - - 2013
Recent evidence supports the idea that robust and, importantly, FLEXIBLE automaticity of cardiac pacemaker cells is conferred by a coupled system of membrane ion currents (an "M-clock") and a sarcoplasmic reticulum (SR)-based Ca(2+) oscillator ("Ca(2+)clock") that generates spontaneous diastolic Ca(2+) releases. This study identified numerical models of a human biological ...
Liu Xin - - 2013
The performance of cooperative spectrum sensing in cognitive radio (CR) networks depends on the sensing mode, the sensing time and the number of cooperative users. In order to improve the sensing performance and reduce the interference to the primary user (PU), a periodic cooperative spectrum sensing model based on weight ...
Verkerk Arie O - - 2013
A typical feature of sinoatrial (SA) node pacemaker cells is the presence of an ionic current that activates upon hyperpolarization. The role of this hyperpolarization-activated current, I f , which is also known as the "funny current" or "pacemaker current," in the spontaneous pacemaker activity of SA nodal cells remains ...
Kumar Sushil - - 2013
Sensing coverage problem in wireless sensor networks is a measure of quality of service (QoS). Coverage refers to how well a sensing field is monitored or tracked by the sensors. Aim of the paper is to have a priori estimate for number of sensors to be deployed in a harsh ...
Nguyen Thu L N TL School of Electronic Engineering, Soongsil University, Seoul 156-743, Republic of - - 2013
Compressive sensing is a sampling method which provides a new approach to efficient signal compression and recovery by exploiting the fact that a sparse signal can be suitably reconstructed from very few measurements. One of the most concerns in compressive sensing is the construction of the sensing matrices. While random ...
da Silva Kátia Regina KR Heart Institute, InCor, Clinics Hospital of the University of São Paulo Medical School, São Paulo, Brazil. - - 2013
The ability to apply standard and interoperable solutions for implementing and managing medical registries as well as aggregate, reproduce, and access data sets from legacy formats and platforms to advanced standard formats and operating systems are crucial for both clinical healthcare and biomedical research settings. Our study describes a reproducible, ...
Jasuja Om Prakash - - 2012
The latent fingermarks developed with iodine fumes are not permanent due to the sublimation of iodine. In this paper a new method has been proposed to fix the latent fingermarks developed with iodine fumes. Latent fingermarks were developed on both porous as well as non-porous substrates which were subsequently fixed ...
Fok Pak-Wing - - 2012
Atherosclerosis is an inflammatory disease of the artery characterized by an expansion of the intimal region. Intimal thickening is usually attributed to the migration of smooth muscle cells (SMCs) from the surrounding media and proliferation of SMCs already present in the intima. Intimal expansion can give rise to dangerous events ...
Chen Ming-Hui MH Department of Statistics, University of Connecticut, Storrs, CT, - - 2012
In this paper, we propose a class of multivariate random effects models allowing for the inclusion of study-level covariates to carry out meta-analyses. As existing algorithms for computing maximum likelihood estimates often converge poorly or may not converge at all when the random effects are multi-dimensional, we develop an efficient ...
Kuehnel F - - 2012
Common marmosets are suitable non-human primate models for many human diseases. Standard values for blood parameters are required to evaluate physiological and pathological situations. Two studies were conducted: study I to determine standard values and study II to examine these under changed housing conditions. In study I, all parameters for ...
Castello Michael A - - 2012
According to the amyloid cascade hypothesis, accumulation of the amyloid peptide Aβ, derived by proteolytic processing from the amyloid precursor protein (APP), is the key pathogenic trigger in Alzheimer's disease (AD). This view has led researchers for more than two decades and continues to be the most influential model of ...
Olofsson Sven-Olof - - 2012
In this short review, we discuss apolipoprotein B100 and the assembly of very low-density lipoproteins. In particular, we address the nature and importance of co- and posttranslational degradation of apolipoprotein B100 during the assembly process. We also provide a short historical background to the development of the current model for ...
Stevenson Jennifer E - - 2012
OBJECTIVE: The purpose of this research was to utilize a structural equation modeling (SEM) approach to simultaneously examine the relationship among the Metabolic Syndrome (MetSyn) and coronary artery calcification (CAC), a surrogate marker for sub-clinical atherosclerosis and coronary artery disease (CAD). MATERIALS/METHODS: Data were derived from the Spokane Heart Study ...
Hadley K R - - 2012
Computer simulations are an attractive means by which to probe the self-assembly and molecular level organization of lipids in biological membranes. In this work, we study a simple skin lipid system to demonstrate the ability of the coarse-grained models used for fatty acids, cholesterol, and water to self-assemble, thus validating ...
van Kempen Bob J H - - 2012
PURPOSE: Modeling studies that evaluate statin treatment for the prevention of cardiovascular disease (CVD) use different methods to model the effect of statins. The aim of this study was to evaluate the impact of using different modeling methods on the optimal decision found in such studies. METHODS: We used a ...
Chhabria Mahesh T - - 2012
The present study describes ligand-based pharmacophore modeling of a series of structurally diverse acyl coenzyme A cholesterol acyltransferase (ACAT) inhibitors. Quantitative pharmacophore models were generated using HypoGen module of Discovery Studio 2.1 whereby the best pharmacophore model possessing two hydrophobic, one ring aromatic and one hydrogen bond acceptor feature for ...
Getz Godfrey S GS Department of Pathology, University of Chicago, Chicago, IL 60637, USA. - - 2012
Atherosclerosis is a chronic inflammatory disorder that is the underlying cause of most cardiovascular disease. Both cells of the vessel wall and cells of the immune system participate in atherogenesis. This process is heavily influenced by plasma lipoproteins, genetics, and the hemodynamics of the blood flow in the artery. A ...
David Stephanie - - 2012
Several siRNA (small interfering RNA) therapeutics are undergoing clinical trials for cancer, respiratory diseases or macular degeneration, but most are administrated locally. In order to overcome the different barriers to attain an efficient siRNA action after systemic administration, nanocarriers able to carry and protect siRNA are awaited. With this aim, ...
Ibrahim Fady - - 2012
The purpose of this study was to investigate the intraluminal processing of novel oral lipid-based formulations of amphotericin B using an in vitro lipolysis model. Amphotericin B (AmB) was formulated in three lipid-based formulations consisting of different lipid components; iCo-009, iCo-010 and iCo-011. Various lipid loads (0.25, 0.5, 1 and ...
Jawien Jacek - - 2012
Although atherosclerosis was previously thought to be mainly a degenerative disease, it is now well ascertained that its pathogenesis is inflammatory. There was a pivotal role of apoE-knockout mice in understanding the inflammatory background of atherosclerosis. Currently, atherosclerosis is known as a chronic inflammatory disease, in most cases initiated by ...
Sahni Ekneet - - 2012
This review provides a comprehensive record of experimental and modeling approaches that can be used to study the effect of critical process parameters affecting the coating uniformity in pharmaceutical coating operation. Explicit reference is given to the development of the approach and its previous usage with particular emphasis on the ...
Xu Cheng-Jian - - 2012
PURPOSE: To study the impact of different statistical learning methods on the prediction performance of multivariate normal tissue complication probability (NTCP) models. METHODS AND MATERIALS: In this study, three learning methods, stepwise selection, least absolute shrinkage and selection operator (LASSO), and Bayesian model averaging (BMA), were used to build NTCP ...
Doyley M M - - 2012
Elastography is emerging as an imaging modality that can distinguish normal versus diseased tissues via their biomechanical properties. This paper reviews current approaches to elastography in three areas--quasi-static, harmonic and transient--and describes inversion schemes for each elastographic imaging approach. Approaches include first-order approximation methods; direct and iterative inversion schemes for ...
DeLouise Lisa A LA Department of Biomedical Engineering, University of Rochester, Rochester, New York 14642, USA. - - 2012
What are nanoparticles and why are they important in dermatology? These questions are addressed by highlighting recent developments in the nanotechnology field that have increased the potential for intentional and unintentional nanoparticle skin exposure. The role of environmental factors in the interaction of nanoparticles with skin and the potential mechanisms ...
Sasso Alan F - - 2012
A lipid-based physiologically based toxicokinetic (PBTK) model has been developed for a mixture of six polychlorinated biphenyls (PCBs) in rats. The aim of this study was to apply population Bayesian analysis to a lipid PBTK model, while incorporating an internal exposure-response model linking enzyme induction and metabolic rate. Lipid-based physiologically ...
Teli Mahesh Kumar - - 2012
Coronary heart disease continues to be the leading cause of mortality and a significant cause of morbidity and account for nearly 30% of all deaths each year worldwide. High levels of cholesterol are an important risk factor for coronary heart disease. The blockage of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase activity ...
Vasquez Elisardo C - - 2012
Genetically engineered mouse models and advances in molecular biotechnology have given extensive aid to experimental studies of cardiovascular mechanisms and dysfunction in pathological states such as atherosclerosis. Among the available animal models that have been developed to study atherosclerosis, the apolipoprotein E-deficient (apoE(-/-)) mouse is the most ideal genetically modified ...
Denman Robert B - - 2012
This chapter answers three basic questions, which are: (1) Why build models, (2) why build models of fragile X syndrome, and (3) what has been learned from the models of fragile X syndrome that have been made? The first question is used to frame the other two questions, providing the ...
Chambers David W - - 2012
Practice is fundamentally built on a sense for what is the case. Ideally, there is a scientific or at least rational overlay. But practice is inescapably grounded in flash judgments made by professionals trained to do so. There is virtually no scientific literature about this most basic type of clinical ...
Kepseu Wilfred D - - 2012
Bacterial virulence is a multifactorial process. In this chapter, we review some known mechanisms used by bacteria to trigger their production of virulence factors. We develop the idea that although the onset of virulence shows up an abrupt transition, the modelling of this dynamics can be classified in two qualitatively ...
Cho Dong-Sik - - 2012
Increased low-density lipoprotein cholesterol (LDL) concentration is associated with increased risk of coronary heart disease (CHD) but a substantial risk of cardiovascular disease often remains after LDL concentrations have been treated to target. Apolipoprotein B (apo B) is the major apolipoprotein contained within atherogenic lipoproteins such as LDL, and apo ...
Wong Kelvin Kl - - 2012
This study characterizes the distribution and components of plaque structure by presenting a three-dimensional blood-vessel modelling with the aim of determining mechanical properties due to the effect of lipid core and calcification within a plaque. Numerical simulation has been used to answer how cap thickness and calcium distribution in lipids ...
Yu Chen C Department of Psychological and Brain Sciences and Program in Cognitive Science, Indiana University, Bloomington, IN 47405, USA. - - 2012
Both adults and young children possess powerful statistical computation capabilities--they can infer the referent of a word from highly ambiguous contexts involving many words and many referents by aggregating cross-situational statistical information across contexts. This ability has been explained by models of hypothesis testing and by models of associative learning. ...
Jones Gareth G School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, United Kingdom. - - 2012
Ectopic foci originating from the pulmonary veins (PVs) have been suggested as the underlying cause for generating atrial arrhythmias that include atrial fibrillation (AF). Recent experimental findings indicate two types of PV cells: pacemaking and non-pacemaking. In this study, we have developed two mathematical models for human PV cardiomyocytes with ...
Ning Xia - - 2012
The identification of small potent compounds that selectively bind to the target under consideration with high affinities is a critical step toward successful drug discovery. However, there is still a lack of efficient and accurate computational methods to predict compound selectivity properties. In this paper, we propose a set of ...
Lin Hui-Yi HY H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL, USA. - - 2012
Studies have shown that interactions of single nucleotide polymorphisms (SNPs) may play an important role in understanding the causes of complex disease. We have proposed an integrated machine learning method that combines two machine-learning methods-Random Forests (RF) and Multivariate Adaptive Regression Splines (MARS)-to identify a subset of important SNPs and ...
Stewart Adam Michael - - 2011
Epilepsy is a complex brain disorder with multiple underlying causes and poorly understood pathogenetic mechanisms. Animal models have been indispensable tools in experimental epilepsy research. Zebrafish (Danio rerio) are rapidly emerging as a promising model organism to study various brain disorders. Seizure-like behavioral and neurophysiological responses can be evoked in ...
Marschalko Marian - - 2011
Underground mining activities may potentially play a role on the initiation and reactivation of the slope movements. However, an adequate attention has not yet been paid to these problems; in this study, the possible influence of present and former mining activities on the selected set of model slope deformations in ...
Gottfried Jay A - - 2011
Neuroscientific research has emphatically promoted the idea that the key function of the orbitofrontal cortex (OFC) is to encode value. Associative learning studies indicate that OFC representations of stimulus cues reflect the predictive value of expected outcomes. Neuroeconomic studies suggest that the OFC distills abstract representations of value from discrete ...
Doménech Antonio - - 2011
Historic Chemistry: The discovery of a set of greenish pellets from ancient plaster at the La Blanca archaeological site (Guatemala) provides evidence that the Maya people used a material akin to Maya Blue also outside of pottery, murals, sculptures or religious context. Obviously, the Maya people developed different preparative strategies ...
Curran-Everett Douglas - - 2011
Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This seventh installment of Explorations in Statistics explores regression, a technique that estimates the nature of the relationship between two things for which we may only surmise a mechanistic or ...
Baruque Bruno - - 2011
This paper presents a novel model for performing classification and visualization of high-dimensional data by means of combining two enhancing techniques. The first is a semi-supervised learning, an extension of the supervised learning used to incorporate unlabeled information to the learning process. The second is an ensemble learning to replicate ...
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