keyword
MENU ▼
Read by QxMD icon Read
search

State dependent model

keyword
https://www.readbyqxmd.com/read/29166451/factors-associated-with-frailty-in-a-community-dwelling-population-of-older-adults
#1
Danielle Teles da Cruz, Marcel de Toledo Vieira, Ronaldo Rocha Bastos, Isabel Cristina Gonçalves Leite
OBJECTIVE: To analyze if demographic and socioeconomic factors and factors related to health and health services are associated with frailty in community-dwelling older adults. METHODS: This is a cross-sectional study with 339 older adults (60 years old or more) living in Juiz de Fora, State of Minas Gerais, Brazil, in 2015. A household survey was carried out and frailty was evaluated using the Edmonton Frail Scale. For the analysis of the factors associated with outcome, a theoretical model of determination was constructed with three hierarchical blocks: block 1 with demographic and socioeconomic characteristics, block 2 with the health of the older adult (divided into three sub-levels: 2...
2017: Revista de Saúde Pública
https://www.readbyqxmd.com/read/29166153/catastrophic-shifts-in-semiarid-vegetation-soil-systems-may-unfold-rapidly-or-slowly
#2
Derek Karssenberg, Marc F P Bierkens, Max Rietkerk
Under gradual change of a driver, complex systems may switch between contrasting stable states. For many ecosystems it is unknown how rapidly such a critical transition unfolds. Here we explore the rate of change during the degradation of a semiarid ecosystem with a model coupling the vegetation and geomorphological system. Two stable states-vegetated and bare-are identified, and it is shown that the change between these states is a critical transition. Surprisingly, the critical transition between the vegetated and bare state can unfold either rapidly over a few years or gradually over decennia up to millennia, depending on parameter values...
December 2017: American Naturalist
https://www.readbyqxmd.com/read/29166120/mechanical-response-of-transient-telechelic-networks-with-many-part-stickers
#3
Michelle K Sing, Jorge Ramírez, Bradley D Olsen
A central question in soft matter is understanding how several individual, weak bonds act together to produce collective interactions. Here, gel-forming telechelic polymers with multiple stickers at each chain end are studied through Brownian dynamics simulations to understand how collective interaction of the bonds affects mechanical response of the gels. These polymers are modeled as finitely extensible dumbbells using an explicit tau-leap algorithm and the binding energy of these associations was kept constant regardless of the number of stickers...
November 21, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/29166116/theoretical-study-of-photodetachment-spectroscopy-of-hydrogenated-boron-cluster-anion-h2b7-and-its-deuterated-isotopomer
#4
Rudraditya Sarkar, S Mahapatra
Photodetachment spectroscopy of H2B7(-) and its deuterated isotopomer probing the energetically low-lying electronic states of the respective neutral cluster is theoretically investigated in this paper. The theoretical methodology is based on detailed quantum chemistry calculations of electronic state energies, construction of a vibronic coupling model in the diabatic electronic basis, and nuclear dynamics calculations from first principles using time-dependent and time-independent quantum mechanical methods...
November 21, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/29166106/nodeless-vibrational-amplitudes-and-quantum-nonadiabatic-dynamics-in-the-nested-funnel-for-a-pseudo-jahn-teller-molecule-or-homodimer
#5
William K Peters, Vivek Tiwari, David M Jonas
The nonadiabatic states and dynamics are investigated for a linear vibronic coupling Hamiltonian with a static electronic splitting and weak off-diagonal Jahn-Teller coupling through a single vibration with a vibrational-electronic resonance. With a transformation of the electronic basis, this Hamiltonian is also applicable to the anti-correlated vibration in a symmetric homodimer with marginally strong constant off-diagonal coupling, where the non-adiabatic states and dynamics model electronic excitation energy transfer or self-exchange electron transfer...
November 21, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/29166098/pulling-force-and-surface-tension-drive-membrane-fusion
#6
Xuejuan Liu, Falin Tian, Tongtao Yue, Xianren Zhang, Chongli Zhong
Despite catalyzed by fusion proteins of quite different molecular architectures, intracellular, viral, and cell-to-cell fusions are found to have the essential common features and the nearly same nature of transition states. The similarity inspires us to find a more general catalysis mechanism for membrane fusion that minimally depends on the specific structures of fusion proteins. In this work, we built a minimal model for membrane fusion, and by using dissipative particle dynamics simulations, we propose a mechanism that the pulling force generated by fusion proteins initiates the fusion process and the membrane tension regulates the subsequent fusion stages...
November 21, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/29166096/building-better-water-models-using-the-shape-of-the-charge-distribution-of-a-water-molecule
#7
Chamila Chathuranga Dharmawardhana, Toshiko Ichiye
The unique properties of liquid water apparently arise from more than just the tetrahedral bond angle between the nuclei of a water molecule since simple three-site models of water are poor at mimicking these properties in computer simulations. Four- and five-site models add partial charges on dummy sites and are better at modeling these properties, which suggests that the shape of charge distribution is important. Since a multipole expansion of the electrostatic potential describes a charge distribution in an orthogonal basis set that is exact in the limit of infinite order, multipoles may be an even better way to model the charge distribution...
November 21, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/29166083/water-structure-around-hydrophobic-amino-acid-side-chain-analogs-using-different-water-models
#8
Timir Hajari, Sanjoy Bandyopadhyay
The water structure around hydrophobic groups governs various biochemical processes. There is an ongoing debate on whether water molecules near hydrophobic groups are more ordered with greater participation in water-water hydrogen bonding with respect to water in the pure bulk state. The water structure around six different hydrophobic amino acid side chain analog molecules has been studied in pure water using molecular dynamics simulations. The analysis of water tetrahedral order parameter and the number of hydrogen bonds formed by the individual water molecules in the first hydration shell of the hydrophobic analogs provide evidence that both ordering and hydrogen bonds involving water molecules are to some extent reduced in the hydrophobic hydration shell...
June 14, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/29166081/three-sources-of-errors-in-the-ehrenfest-treatment-of-inelastic-scattering-and-possible-ways-of-resolving-them
#9
Alexander Semenov, Dmitri Babikov
In order to identify the origin of possible errors in the mixed quantum/classical approach to inelastic scattering [A. Semenov and D. Babikov, J. Chem. Phys. 140, 044306 (2014) and A. Semenov, M.-L. Dubernet, and D. Babikov, J. Chem. Phys. 141, 114304 (2014)], a simplified model is considered that consists of one intermolecular degree of freedom and two intramolecular states, coupled by a simple potential. For this system, analytic derivations are carried out to determine (i) the exact quantum mechanical solution of the inelastic scattering problem, (ii) a simplified version of it with all oscillatory terms neglected, and (iii) the Ehrenfest solution in which the translational motion is described by the mean-field trajectory while the internal molecular motion is treated by the time-dependent Schrodinger equation...
June 14, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/29166021/differences-in-the-aspect-ratio-of-gold-nanorods-that-induce-defects-in-cell-membrane-models
#10
Paula M P Lins, Valeria Spolon Marangoni, Thiers M Uehara, Paulo Barbeitas Miranda, Valtencir Zucolotto, Juliana Cancino Bernardi
Understanding the interactions between biomolecules and nanomaterials is of great importance for many areas of nanomedicine and bioapplications. Although studies in this area have been performed, the interactions between cell membranes and nanoparticles are not fully understood. Here, we investigate the interactions that occur between the Langmuir monolayers of dipalmitoylphosphatidyl glycerol (DPPG) and dipalmitoylphosphatidyl choline (DPPC) with gold nanorods (NR) - with three aspect ratios - and gold nanoparticles...
November 22, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/29165842/nitrogen-reduction-to-ammonia-on-a-biomimetic-mononuclear-iron-centre-insights-into-the-nitrogenase-enzyme
#11
Samuel de Visser, Monika Kaczmarek, Abheek Malhotra, Alex Balan, Amy Timmins
Nitrogenases catalyze the nitrogen fixation to ammonia on a multinuclear Fe-Mo centre, but their mechanism and particularly the order of proton and electron transfer processes that happen during the catalytic cycle is still unresolved. Recently, a unique biomimetic mononuclear iron model was developed using tris(phosphine)borate (TPB) ligands that was shown to convert N2 into NH3. Herein, we present a computational study on the [(TPB)FeN2]- complex and its conversion to ammonia through the addition of electrons and protons...
November 22, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/29165587/identification-of-diverse-target-rnas-that-are-functionally-regulated-by-human-pumilio-proteins
#12
Jennifer A Bohn, Jamie L Van Etten, Trista L Schagat, Brittany M Bowman, Richard C McEachin, Peter L Freddolino, Aaron C Goldstrohm
Human Pumilio proteins, PUM1 and PUM2, are sequence specific RNA-binding proteins that regulate protein expression. We used RNA-seq, rigorous statistical testing and an experimentally derived fold change cut-off to identify nearly 1000 target RNAs-including mRNAs and non-coding RNAs-that are functionally regulated by PUMs. Bioinformatic analysis defined a PUM Response Element (PRE) that was significantly enriched in transcripts that increased in abundance and matches the PUM RNA-binding consensus. We created a computational model that incorporates PRE position and frequency within an RNA relative to the magnitude of regulation...
November 20, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/29164138/modeling-the-costs-of-postpartum-dysgalactia-syndrome-and-locomotory-disorders-on-sow-productivity-and-replacement
#13
Jarkko K Niemi, Paula Bergman, Sami Ovaska, Marja-Liisa Sevón-Aimonen, Mari Heinonen
Postpartum dysgalactia syndrome (PPDS) and locomotory disorders are common health problems in sows. Previous research suggests that they can cause substantial losses, reduce sow welfare, and result in premature removal of the sow from the herd. However, economic consequences of PPDS and locomotory disorders have not been investigated thoroughly. The goal of this study was to examine economic losses caused by PPDS and locomotory disorders and their impacts on sow longevity. A stochastic dynamic programming model, which maximizes return on sow space unit and assesses sow replacement under several scenarios, was developed...
2017: Frontiers in Veterinary Science
https://www.readbyqxmd.com/read/29163328/parkinson-s-disease-severity-at-3%C3%A2-years-can-be-predicted-from-non-motor-symptoms-at-baseline
#14
Alba Ayala, José Matías Triviño-Juárez, Maria João Forjaz, Carmen Rodríguez-Blázquez, José-Manuel Rojo-Abuin, Pablo Martínez-Martín
Objective: The aim of this study is to present a predictive model of Parkinson's disease (PD) global severity, measured with the Clinical Impression of Severity Index for Parkinson's Disease (CISI-PD). Methods: This is an observational, longitudinal study with annual follow-up assessments over 3 years (four time points). A multilevel analysis and multiple imputation techniques were performed to generate a predictive model that estimates changes in the CISI-PD at 1, 2, and 3 years...
2017: Frontiers in Neurology
https://www.readbyqxmd.com/read/29163179/in-silico-assessment-of-efficacy-and-safety-of-ikur-inhibitors-in-chronic-atrial-fibrillation-role-of-kinetics-and-state-dependence-of-drug-binding
#15
Nicholas Ellinwood, Dobromir Dobrev, Stefano Morotti, Eleonora Grandi
Current pharmacological therapy against atrial fibrillation (AF), the most common cardiac arrhythmia, is limited by moderate efficacy and adverse side effects including ventricular proarrhythmia and organ toxicity. One way to circumvent the former is to target ion channels that are predominantly expressed in atria vs. ventricles, such as KV1.5, carrying the ultra-rapid delayed-rectifier K(+) current (IKur). Recently, we used an in silico strategy to define optimal KV1.5-targeting drug characteristics, including kinetics and state-dependent binding, that maximize AF-selectivity in human atrial cardiomyocytes in normal sinus rhythm (nSR)...
2017: Frontiers in Pharmacology
https://www.readbyqxmd.com/read/29163144/the-relationship-of-cognitive-performance-and-the-theta-alpha-power-ratio-is-age-dependent-an-eeg-study-of-short-term-memory-and-reasoning-during-task-and-resting-state-in-healthy-young-and-old-adults
#16
Janet P Trammell, Priscilla G MacRae, Greta Davis, Dylan Bergstedt, Ariana E Anderson
Objective: The Theta-Alpha ratio (TAR) is known to differ based upon age and cognitive ability, with pathological electroencephalography (EEG) patterns routinely found within neurodegenerative disorders of older adults. We hypothesized that cognitive ability would predict EEG metrics differently within healthy young and old adults, and that healthy old adults not showing age-expected EEG activity may be more likely to demonstrate cognitive deficits relative to old adults showing these expected changes. Methods: In 216 EEG blocks collected in 16 young and 20 old adults during rest (eyes open, eyes closed) and cognitive tasks (short-term memory [STM]; matrix reasoning [RM; Raven's matrices]), models assessed the contributing roles of cognitive ability, age, and task in predicting the TAR...
2017: Frontiers in Aging Neuroscience
https://www.readbyqxmd.com/read/29163063/acetylcholine-neuromodulation-in-normal-and-abnormal-learning-and-memory-vigilance-control-in-waking-sleep-autism-amnesia-and-alzheimer-s-disease
#17
Stephen Grossberg
Adaptive Resonance Theory, or ART, is a neural model that explains how normal and abnormal brains may learn to categorize and recognize objects and events in a changing world, and how these learned categories may be remembered for a long time. This article uses ART to propose and unify the explanation of diverse data about normal and abnormal modulation of learning and memory by acetylcholine (ACh). In ART, vigilance control determines whether learned categories will be general and abstract, or specific and concrete...
2017: Frontiers in Neural Circuits
https://www.readbyqxmd.com/read/29162917/keratin-water-nmf-interaction-as-a-three-layer-model-in-the-human-stratum-corneum-using-in-vivo-confocal-raman-microscopy
#18
ChunSik Choe, Johannes Schleusener, Jürgen Lademann, Maxim E Darvin
The secondary and tertiary structure of keratin and natural moisturizing factor (NMF) are of great importance regarding the water regulating functions in the stratum corneum (SC). In this in vivo study, the depth-dependent keratin conformation and its relationship to the hydrogen bonding states of water and its content in the SC, are investigated using confocal Raman microscopy. Based on the obtained depth-profiles for the β-sheet/α-helix ratio, the stability of disulphide bonds, the amount of cysteine forming disulphide bonds, the buried/exposed tyrosine and the folding/unfolding states of keratin, a "three layer model" of the SC, regarding the keratin-water-NMF interaction is proposed...
November 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29162864/dual-mode-manipulating-multicenter-photoluminescence-in-a-single-phased-ba9lu2si6o24-bi-3-eu-3-phosphor-to-realize-white-light-tunable-emissions
#19
Yue Guo, Sung Heum Park, Byung Chun Choi, Jung Hyun Jeong, Jung Hwan Kim
A Bi(3+) and Eu(3+) ion co-doped Ba9Lu2Si6O24 single-phased phosphor was synthesized successfully via a conventional high-temperature solid-state reaction. X-ray diffraction, crystal structure analysis, diffuse reflectance and luminescent spectra, quantum efficiency measurements, and thermal stability analysis were applied to investigate the phase, structure, luminescent and thermal stability properties. From the analyses of the crystal structure and luminescent spectra, we observed four discernible Bi(3+) luminescent centers with peaks at ~363...
November 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29162549/diversification-dynamics-and-transoceanic-eurasian-australian-disjunction-in-the-genus-picris-compositae-induced-by-the-interplay-of-shifts-in-intrinsic-extrinsic-traits-and-paleoclimatic-oscillations
#20
Marek Slovák, Jaromír Kučera, Hans Walter Lack, Jotham Ziffer-Berger, Andrea Melicharková, Eliška Záveská, Peter Vďačný
Understanding transcontinental biogeographic patterns has been one of the main foci of the field of biogeography. While multiple explanations for transcontinental disjunctions have been proposed, little is still known about the relative importance of intrinsic and extrinsic traits for the diversification dynamics of disjunct taxa. Here, we study the evolutionary history of the genus Picris L. (Compositae), a great model for investigating the diversification dynamics of transoceanic bipolar disjunct organisms...
November 18, 2017: Molecular Phylogenetics and Evolution
keyword
keyword
99530
1
2
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"