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https://www.readbyqxmd.com/read/28819276/a-new-mathematical-model-and-experimental-validation-on-foamy-oil-flow-in-developing-heavy-oil-reservoirs
#1
Pengcheng Liu, Zhenbao Mu, Wenhui Li, Yongbin Wu, Xiuluan Li
To model foamy-oil flow in the development of heavy oil reservoirs, three depletion experiments were conducted with foamy oil treated as a pseudo-single-phase flow. In this pseudo single phase, dispersed bubbles are viewed as a part of the oil, and the redefined effective permeability varies with the changes of pressure depletion rate, oil viscosity, and gas saturation. A mathematical expression for the effective permeability was developed based on experiments, where the viscosity of foamy oil is assumed to be approximately equal to the saturated oil under equivalent conditions...
August 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28818710/multivariate-soil-fertility-relationships-for-predicting-the-environmental-persistence-of-2-4-6-trinitrotoluene-tnt-and-1-3-5-trinitro-1-3-5-tricyclohexane-rdx-among-taxonomically-distinct-soils
#2
Chelsea K Katseanes, Mark A Chappell, Bryan G Hopkins, Brian D Durham, Cynthia L Price, Beth E Porter, Lesley F Miller
After nearly a century of use in numerous munition platforms, TNT and RDX contamination has turned up largely in the environment due to ammunition manufacturing or as part of releases from low-order detonations during training activities. Although the basic knowledge governing the environmental fate of TNT and RDX are known, accurate predictions of TNT and RDX persistence in soil remain elusive, particularly given the universal heterogeneity of pedomorphic soil types. In this work, we proposed overcoming this problem by considering the environmental persistence of these munition constituents (MC) as multivariate mathematical functions over a variety of taxonomically distinct soil types, instead of a single constant or parameter of a specific absolute value...
August 14, 2017: Journal of Environmental Management
https://www.readbyqxmd.com/read/28818512/ploc-meuk-predict-subcellular-localization-of-multi-label-eukaryotic-proteins-by-extracting-the-key-go-information-into-general-pseaac
#3
Xiang Cheng, Xuan Xiao, Kuo-Chen Chou
Many efforts have been made in predicting the subcellular localization of eukaryotic proteins, but most of the existing methods have the following two limitations: (1) their coverage scope is less than ten locations and hence many organelles in an eukaryotic cell cannot be covered, and (2) they can only be used to deal with single-label systems in which each of the constituent proteins has one and only one location. Actually, proteins with multiple locations are particularly interesting since they may have some exceptional functions very important for in-depth understanding the biological process in a cell and for selecting drug target as well...
August 14, 2017: Genomics
https://www.readbyqxmd.com/read/28818467/mathematical-modelling-and-analysis-of-the-brassinosteroid-and-gibberellin-signalling-pathways-and-their-interactions
#4
Henry R Allen, Mariya Ptashnyk
The plant hormones brassinosteroid (BR) and gibberellin (GA) have important roles in a wide range of processes involved in plant growth and development. In this paper we derive and analyse new mathematical models for the BR signalling pathway and for the crosstalk between the BR and GA signalling pathways. To analyse the effects of spatial heterogeneity of the signalling processes, along with spatially-homogeneous ODE models we derive coupled PDE-ODE systems modelling the temporal and spatial dynamics of molecules involved in the signalling pathways...
August 14, 2017: Journal of Theoretical Biology
https://www.readbyqxmd.com/read/28818204/geometry-as-a-confounder-when-assessing-ventricular-systolic-function-comparison-between-ejection-fraction-and-strain
#5
Thomas M Stokke, Nina E Hasselberg, Marit K Smedsrud, Sebastian I Sarvari, Kristina H Haugaa, Otto A Smiseth, Thor Edvardsen, Espen W Remme
BACKGROUND: Preserved left ventricular (LV) ejection fraction (EF) and reduced myocardial strain are reported in patients with hypertrophic cardiomyopathy, ischemic heart disease, diabetes mellitus, and more. OBJECTIVES: The authors performed a combined mathematical and echocardiographic study to understand the inconsistencies between EF and strains. METHODS: An analytical equation showing the relationship between EF and the 4 parameters, global longitudinal strain (GLS), global circumferential strain (GCS), wall thickness, and short-axis diameter, was derived from an elliptical LV model...
August 22, 2017: Journal of the American College of Cardiology
https://www.readbyqxmd.com/read/28817625/disentangling-the-relationship-between-children-s-motor-ability-executive-function-and-academic-achievement
#6
Mirko Schmidt, Fabienne Egger, Valentin Benzing, Katja Jäger, Achim Conzelmann, Claudia M Roebers, Caterina Pesce
Even though positive relations between children's motor ability and their academic achievement are frequently reported, the underlying mechanisms are still unclear. Executive function has indeed been proposed, but hardly tested as a potential mediator. The aim of the present study was therefore to examine the mediating role of executive function in the relationship between motor ability and academic achievement, also investigating the individual contribution of specific motor abilities to the hypothesized mediated linkage to academic achievement...
2017: PloS One
https://www.readbyqxmd.com/read/28817568/an-optimal-strategy-for-epilepsy-surgery-disruption-of-the-rich-club
#7
Marinho A Lopes, Mark P Richardson, Eugenio Abela, Christian Rummel, Kaspar Schindler, Marc Goodfellow, John R Terry
Surgery is a therapeutic option for people with epilepsy whose seizures are not controlled by anti-epilepsy drugs. In pre-surgical planning, an array of data modalities, often including intra-cranial EEG, is used in an attempt to map regions of the brain thought to be crucial for the generation of seizures. These regions are then resected with the hope that the individual is rendered seizure free as a consequence. However, post-operative seizure freedom is currently sub-optimal, suggesting that the pre-surgical assessment may be improved by taking advantage of a mechanistic understanding of seizure generation in large brain networks...
August 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28816683/cardiorespiratory-model-based-data-driven-approach-for-sleep-apnea-detection
#8
Sandeep Gutta, Qi Cheng, Hoa Nguyen, Bruce Benjamin
Obstructive sleep apnea (OSA) is a chronic sleep disorder affecting millions of people worldwide. Individuals with OSA are rarely aware of the condition and are often left untreated, which can lead to some serious health problems. Nowadays, several low-cost wearable health sensors are available that can be used to conveniently and noninvasively collect a wide range of physiological signals. In this paper, we propose a new framework for OSA detection in which we combine the wearable sensor measurement signals with the mathematical models of the cardiorespiratory system...
August 14, 2017: IEEE Journal of Biomedical and Health Informatics
https://www.readbyqxmd.com/read/28816679/adaptive-unknown-input-estimation-by-sliding-modes-and-differential-neural-network-observer
#9
Ivan Salgado, Isaac Chairez
In this paper, a differential neural network (DNN) implemented as a robust observer estimates the dynamics of perturbed uncertain nonlinear systems affected by exogenous unknown inputs. In the first stage, the identification error converges into a neighborhood around the origin. Then, the second-order sliding mode supertwisting algorithm implemented as a robust exact differentiator reconstructed the unknown inputs. The approach proposed in this paper can be applied in the case of full access to the state vector (identification problem) and in the case of partial access to the state vector (estimation problem)...
August 15, 2017: IEEE Transactions on Neural Networks and Learning Systems
https://www.readbyqxmd.com/read/28816060/the-broad-spectrum-antimicrobial-potential-of-mn-co-4-s2cnme-ch2co2h-a-water-soluble-co-releasing-molecule-corm-401-intracellular-accumulation-transcriptomic-and-statistical-analyses-and-membrane-polarization
#10
Lauren Katie Wareham, Samantha McLean, Ronald Begg, Namrata Rana, Salar Ali, John J Kendall, Guido Sanguinetti, Brian E Mann, Robert K Poole
AIMS: Carbon monoxide (CO)-releasing molecules (CORMs) are candidates for animal and antimicrobial therapeutics. We aimed to probe the antimicrobial potential of a novel manganese CORM. RESULTS: [Mn(CO)4S2CNMe(CH2CO2H)], CORM-401, inhibits growth of Escherichia coli and several antibiotic-resistant clinical pathogens. CORM-401 releases CO that binds oxidases in vivo but is an ineffective respiratory inhibitor. Extensive CORM accumulation (assayed as intracellular manganese) accompanies antimicrobial activity...
August 17, 2017: Antioxidants & Redox Signaling
https://www.readbyqxmd.com/read/28815994/imrt-qa-using-machine-learning-a-multi-institutional-validation
#11
Gilmer Valdes, Maria F Chan, Seng Boh Lim, Ryan Scheuermann, Joseph O Deasy, Timothy D Solberg
PURPOSE: To validate a machine learning approach to Virtual intensity-modulated radiation therapy (IMRT) quality assurance (QA) for accurately predicting gamma passing rates using different measurement approaches at different institutions. METHODS: A Virtual IMRT QA framework was previously developed using a machine learning algorithm based on 498 IMRT plans, in which QA measurements were performed using diode-array detectors and a 3%local/3 mm with 10% threshold at Institution 1...
August 17, 2017: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/28815557/societal-and-family-lifetime-cost-of-dementia-implications-for-policy
#12
Eric Jutkowitz, Robert L Kane, Joseph E Gaugler, Richard F MacLehose, Bryan Dowd, Karen M Kuntz
OBJECTIVES: To estimate the cost of dementia and the extra cost of caring for someone with dementia over the cost of caring for someone without dementia. DESIGN: We developed an evidence-based mathematical model to simulate disease progression for newly diagnosed individuals with dementia. Data-driven trajectories of cognition, function, and behavioral and psychological symptoms were used to model disease progression and predict costs. Using modeling, we evaluated lifetime and annual costs of individuals with dementia, compared costs of those with and without clinical features of dementia, and evaluated the effect of reducing functional decline or behavioral and psychological symptoms by 10% for 12 months (implemented when Mini-Mental State Examination score ≤21)...
August 17, 2017: Journal of the American Geriatrics Society
https://www.readbyqxmd.com/read/28814583/does-use-of-point-of-care-testing-improve-cost-effectiveness-of-the-nhs-health-check-programme-in-the-primary-care-setting-a-cost-minimisation-analysis
#13
Austen El-Osta, Maria Woringer, Elena Pizzo, Talitha Verhoef, Claire Dickie, Melody Z Ni, Jeremy R Huddy, Michael Soljak, George B Hanna, Azeem Majeed
OBJECTIVE: To determine if use of point of care testing (POCT) is less costly than laboratory testing to the National Health Service (NHS) in delivering the NHS Health Check (NHSHC) programme in the primary care setting. DESIGN: Observational study and theoretical mathematical model with microcosting approach. SETTING: We collected data on NHSHC delivered at nine general practices (seven using POCT; two not using POCT). PARTICIPANTS: We recruited nine general practices offering NHSHC and a pathology services laboratory in the same area...
August 15, 2017: BMJ Open
https://www.readbyqxmd.com/read/28814310/modelling-the-benefits-of-long-acting-or-transmission-blocking-drugs-for-reducing-plasmodium-falciparum-transmission-by-case-management-or-by-mass-treatment
#14
Michael T Bretscher, Jamie T Griffin, Azra C Ghani, Lucy C Okell
BACKGROUND: Anti-malarial drugs are an important tool for malaria control and elimination. Alongside their direct benefit in the treatment of disease, drug use has a community-level effect, clearing the reservoir of infection and reducing onward transmission of the parasite. Different compounds potentially have different impacts on transmission-with some providing periods of prolonged chemoprophylaxis whilst others have greater transmission-blocking potential. The aim was to quantify the relative benefit of such properties for transmission reduction to inform target product profiles in the drug development process and choice of first-line anti-malarial treatment in different endemic settings...
August 16, 2017: Malaria Journal
https://www.readbyqxmd.com/read/28814049/wearable-sensing-for-rehabilitation-after-stroke-bimanual-jerk-asymmetry-encodes-unique-information-about-the-variability-of-upper-extremity-recovery
#15
Diogo S de Lucena, Oliver Stoller, Justin B Rowe, Vicky Chan, David J Reinkensmeyer
Wearable sensing is a new tool for quantifying upper extremity (UE) rehabilitation after stroke. However, it is unclear whether it provides information beyond what is available through standard clinical assessments. To investigate this question, people with a chronic stroke (n=9) wore accelerometers on both wrists for 9 hours on a single day during their daily activities. We used principal components analysis (PCA) to characterize how novel kinematic measures of jerk and acceleration asymmetry, along with conventional measures of limb use asymmetry and clinical function, explained the behavioral variance of UE recovery across participants...
July 2017: IEEE ... International Conference on Rehabilitation Robotics: [proceedings]
https://www.readbyqxmd.com/read/28813980/human-mimetic-forearm-mechanism-towards-bionic-arm
#16
Minsang Seo, Hogyun Kim, Youngjin Choi
The paper presents a mechanical forearm mechanism to extend the pronation and supination (P/S) movement of the trans-radial amputee when he/she is able to conduct the P/S motion partially with his/her remaining forearm. The P/S motions of the existing prostheses and robotic arms developed till now are completely different from those of the human. When we are to develop the robotic prostheses for the amputees, two important issues should be considered such as cosmetic issue to look like normal arm and motion harmony issue between robotic prosthesis and the amputated living arm...
July 2017: IEEE ... International Conference on Rehabilitation Robotics: [proceedings]
https://www.readbyqxmd.com/read/28813938/online-sparse-gaussian-process-based-human-motion-intent-learning-for-an-electrically-actuated-lower-extremity-exoskeleton
#17
Yi Long, Zhi-Jiang Du, Chao-Feng Chen, Wei Dong, Wei-Dong Wang
The most important step for lower extremity exoskeleton is to infer human motion intent (HMI), which contributes to achieve human exoskeleton collaboration. Since the user is in the control loop, the relationship between human robot interaction (HRI) information and HMI is nonlinear and complicated, which is difficult to be modeled by using mathematical approaches. The nonlinear approximation can be learned by using machine learning approaches. Gaussian Process (GP) regression is suitable for high-dimensional and small-sample nonlinear regression problems...
July 2017: IEEE ... International Conference on Rehabilitation Robotics: [proceedings]
https://www.readbyqxmd.com/read/28813895/customized-therapy-using-distributions-of-reaching-errors
#18
Moria F Bittmann, James L Patton, Felix C Huang
While there has been recent success with robotic therapy approaches, individual differences in motor impairments motivate the need for customized therapy. Our latest work with healthy participants considered the likelihood of one's error to construct a customized force field training environment, which we termed an error field. We believe error statistics could characterize individual motor impairments for stroke survivors. Here we present preliminary results from a pilot study testing this therapy technique on individuals following stroke...
July 2017: IEEE ... International Conference on Rehabilitation Robotics: [proceedings]
https://www.readbyqxmd.com/read/28813604/experimental-study-and-mathematical-modeling-of-self-sustained-kinetic-oscillations-in-catalytic-oxidation-of-methane-over-nickel
#19
Elena A Lashina, Vasily V Kaichev, Andrey Aleksandrovich Saraev, Zakhar S Vinokurov, Nataliya A Chumakova, Gennadii Chumakov, Valerii I Bukhtiyarov
The self-sustained kinetic oscillations in the oxidation of CH4 over Ni foil have been studied at atmospheric pressure using an X-ray diffraction technique and mass spectrometry. It has been shown that the regular oscillations appear under oxygen-deficient conditions; CO, CO2, H2, and H2O are detected as the products. According to in situ X-ray diffraction measurements nickel periodically oxidizes to NiO initiating the reaction-rate oscillations. To describe the oscillations we have proposed a 5-stage mechanism of the partial oxidation of methane over Ni and a corresponding three-variable kinetic model...
August 16, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28813485/magnetic-lenz-lenses-improve-the-limit-of-detection-in-nuclear-magnetic-resonance
#20
Nils Spengler, Peter T While, Markus V Meissner, Ulrike Wallrabe, Jan G Korvink
A high NMR detection sensitivity is indispensable when dealing with mass and volume-limited samples, or whenever a high spatial resolution is required. The use of miniaturised RF coils is a proven way to increase sensitivity, but situations may arise where space restrictions could prevent the use of a small resonant coil, e.g., in the interior of the smallest practicable micro-coils. We present the use of magnetic lenses, denoted as Lenz lenses due to their working principle, to focus the magnetic flux of an RF coil into a smaller volume and thereby locally enhance the sensitivity of the NMR experiment-at the expense of the total sensitive volume...
2017: PloS One
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