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https://www.readbyqxmd.com/read/28732165/complexity-reduction-in-large-quantum-systems-fragment-identification-and-population-analysis-via-a-local-optimized-minimal-basis
#1
Stephan Mohr, Michel Masella, Laura Elizabeth Ratcliff, Luigi Genovese
We present, within Kohn-Sham Density Functional Theory calculations, a quantitative method to identify and assess the partitioning of a large quantum mechanical system into fragments. We then show how within this framework simple generalizations of other well-known population analyses can be used to extract, from first principles, reliable electrostatic multipoles for the identified fragments. Our approach reduces arbitrariness in the fragmentation procedure, and enables the possibility to assess, quantitatively, whether the corresponding fragment multipoles can be interpreted as observable quantities associated to a system's moiety...
July 21, 2017: Journal of Chemical Theory and Computation
https://www.readbyqxmd.com/read/28732163/diamines-can-initiate-new-particle-formation-in-the-atmosphere
#2
Jonas Elm, Monica Passananti, Theo Kurtén, Hanna Vehkamaki
Recent experimental evidence suggests that diamines can enhance atmospheric new particle formation more efficiently compared to monoamines such as dimethylamine. Here we investigate the molecular interactions between sulfuric acid (sa) and the di- amine putrescine (put) using computational methods. The molecular structure of up to four sulfuric acid molecules and up to four putrescine molecules were obtained at the ωB97X-D/6-31++G(d,p) level of theory. We utilized a domain local pair natural orbital coupled cluster method - DLPNO-CCSD(T)/aug-cc-pVTZ - to obtain highly accurate binding energies of the clusters...
July 21, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28731839/cost-benefit-arbitration-between-multiple-reinforcement-learning-systems
#3
Wouter Kool, Samuel J Gershman, Fiery A Cushman
Human behavior is sometimes determined by habit and other times by goal-directed planning. Modern reinforcement-learning theories formalize this distinction as a competition between a computationally cheap but inaccurate model-free system that gives rise to habits and a computationally expensive but accurate model-based system that implements planning. It is unclear, however, how people choose to allocate control between these systems. Here, we propose that arbitration occurs by comparing each system's task-specific costs and benefits...
July 1, 2017: Psychological Science
https://www.readbyqxmd.com/read/28731755/spacetime-symmetries-and-conformal-data-in-the-continuous-multiscale-entanglement-renormalization-ansatz
#4
Q Hu, G Vidal
The generalization of the multiscale entanglement renormalization ansatz (MERA) to continuous systems, or cMERA [Haegeman et al., Phys. Rev. Lett. 110, 100402 (2013)PRLTAO0031-900710.1103/PhysRevLett.110.100402], is expected to become a powerful variational ansatz for the ground state of strongly interacting quantum field theories. In this Letter, we investigate, in the simpler context of Gaussian cMERA for free theories, the extent to which the cMERA state |Ψ^{Λ}⟩ with finite UV cutoff Λ can capture the spacetime symmetries of the ground state |Ψ⟩...
July 7, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28731730/uhlmann-connection-in-fermionic-systems-undergoing-phase-transitions
#5
Bruno Mera, Chrysoula Vlachou, Nikola Paunković, Vítor R Vieira
We study the behavior of the Uhlmann connection in systems of fermions undergoing phase transitions. In particular, we analyze some of the paradigmatic cases of topological insulators and superconductors in one dimension, as well as the BCS theory of superconductivity in three dimensions. We show that the Uhlmann connection signals phase transitions in which the eigenbasis of the state of the system changes. Moreover, using the established fidelity approach and the study of the edge states, we show the absence of thermally driven phase transitions in the case of topological insulators and superconductors...
July 7, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28731351/theory-of-light-modulated-emission-spectroscopy
#6
Mehdi Ansari-Rad, Juan Bisquert
Perovskite solar cells and fluorescent collectors formed by a dispersion of quantum dots in a transparent solid are paradigmatic devices for photon capture and utilization that involve the coupling of photon displacement, absorption and regeneration. In order to obtain information about the coupled photonic processes in systems involving photon recycling, we analyse the transfer function for modulated outgoing to incoming photon flux. We show the physical features of light-to-light impedance that reveals a trap-limited diffusion of photons coupled with the nonradiative recombination...
July 21, 2017: Journal of Physical Chemistry Letters
https://www.readbyqxmd.com/read/28731081/metal-mediated-reactions-between-dialkylcyanamides-and-acetamidoxime-generate-unusual-nitrosoguanidinate-nickel-ii-complexes
#7
Zarina M Bikbaeva, Alexander S Novikov, Vitalii V Suslonov, Nadezhda A Bokach, Vadim Yu Kukushkin
The nitrosoguanidinate complexes [Ni{NH[double bond, length as m-dash]C(NR2)NN(O)}2] (R2 = Me21, (CH2)4O 2, (CH2)43, (CH2)54, (Me)Ph 5, Ph26, (p-MeC6H4)27) were obtained in low-to-moderate (12-26%) yields but reproducible yields in an unexpected metal-mediated reaction in MeOH between the nickel salt NiCl2·2H2O, N,N-disubstituted cyanamides NCNR2, and the amidoxime MeC([double bond, length as m-dash]NOH)NH2. These complexes were formed along with a spectrum of cyanamide-oxime coupling products. The IR and X-ray data indicate the delocalization within the NNO and NCN systems of the nitrosoguanidinate ligand...
July 21, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28730744/improving-hospital-discharge-arrangements-for-people-who-are-homeless-a-realist-synthesis-of-the-intermediate-care-literature
#8
REVIEW
Michelle Cornes, Martin Whiteford, Jill Manthorpe, Joanne Neale, Richard Byng, Nigel Hewett, Michael Clark, Alan Kilmister, James Fuller, Robert Aldridge, Michela Tinelli
This review presents a realist synthesis of "what works and why" in intermediate care for people who are homeless. The overall aim was to update an earlier synthesis of intermediate care by capturing new evidence from a recent UK government funding initiative (the "Homeless Hospital Discharge Fund"). The initiative made resources available to the charitable sector to enable partnership working with the National Health Service (NHS) in order to improve hospital discharge arrangements for people who are homeless...
July 20, 2017: Health & Social Care in the Community
https://www.readbyqxmd.com/read/28730720/microstructural-white-matter-brain-abnormalities-in-patients-with-idiopathic-fecal-incontinence
#9
J Muthulingam, S Haas, T M Hansen, S Laurberg, L Lundby, H S Jørgensen, A M Drewes, K Krogh, J B Frøkjaer
BACKGROUND: Abnormal central nervous system processing of visceral sensation may be a part of the pathogenesis behind idiopathic fecal incontinence (IFI). Our aim was to characterize brain differences in patients with IFI and healthy controls by means of structural magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI). METHODS: In 21 female patients with IFI and 15 female healthy controls, whole-brain structural differences in gray matter volume (GMV), cortical thickness, and white matter tracts fractional anisotropy (FA) were quantified...
July 21, 2017: Neurogastroenterology and Motility: the Official Journal of the European Gastrointestinal Motility Society
https://www.readbyqxmd.com/read/28730559/fathers-know-best-inner-city-african-american-fathers-perceptions-regarding-their-involvement-in-the-pediatric-medical-home
#10
Orville Newton-Ray Bignall, Whitney J Raglin Bignall, Lisa M Vaughn, Ndidi I Unaka
OBJECTIVE: Despite nearly three in four African American (AA) children being born to unwed mothers, AA fathers maintain relatively high levels of parenting engagement, whether or not they live with their children. While father involvement correlates with decreased adverse child health outcomes, the nature of AA father involvement in child health-including engagement in the pediatric medical home-remains largely unexplored. Our study aimed to assess perceptions of pediatric medical home participation among a cohort of urban, AA fathers...
July 20, 2017: Journal of Racial and Ethnic Health Disparities
https://www.readbyqxmd.com/read/28730402/theoretical-perspectives-of-adherence-to-web-based-interventions-a-scoping-review
#11
Cathal Ryan, Michael Bergin, John Sg Wells
PURPOSE: The purpose of this paper is to review the literature as this relates to theoretical perspectives of adherence to web-based interventions, drawing upon empirical evidence from the fields of psychology, business, information technology and health care. METHODS: A scoping review of the literature utilising principles outlined by Arksey and O'Malley was undertaken. RESULTS: Several relevant theoretical perspectives have emerged, eight of which are charted and discussed in this review...
July 20, 2017: International Journal of Behavioral Medicine
https://www.readbyqxmd.com/read/28730353/an-exploration-into-the-bacterial-community-under-different-pasteurization-conditions-during-substrate-preparation-composting-phase-ii-for-agaricus-bisporus-cultivation
#12
Fabricio Rocha Vieira, John Andrew Pecchia
Substrate preparation (i.e., composting) for Agaricus bisporus cultivation is the most critical point of mushroom production. Among many factors involved in the composting process, the microbial ecology of the system is the underlying drive of composting and can be influenced by composting management techniques. Pasteurization temperature at the beginning of phase II, in theory, may influence the bacterial community and subsequently the "selectivity" and nutrition of the final substrate. Therefore, this hypothesis was tested by simulation in bioreactors under different pasteurization conditions (57 °C/6 h, 60 °C/2 h, and 68 °C/2 h), simulating conditions adopted by many producers...
July 20, 2017: Microbial Ecology
https://www.readbyqxmd.com/read/28730352/exploring-the-potential-energy-surface-of-novel-h-s-se-br-species-a-high-level-first-principle-study
#13
S U A Ramjauny, I A Alswaidan, N B Jaufeerally-Safee, L Rhyman, P Ramasami
The characterization of the seleno-sulfide-bromo systems and the isomerization process on the [H, S, Se, Br] potential energy surface were investigated using state-of-the-art theoretical methods. The CCSD(T) and the MP2 levels of theory were employed along with the series of correlation consistent basis sets extrapolated to the complete basis set (CBS) limit in the optimization of the geometrical parameters and computation of electronic energies. The relative stability, in kcal mol(-1), at the CCSD(T)/CBS follows the trend: HSSeBr (0) > HSeSBr (9...
August 2017: Journal of Molecular Modeling
https://www.readbyqxmd.com/read/28729927/fatigue-and-cognition-pupillary-responses-to-problem-solving-in-early-multiple-sclerosis-patients
#14
Sigrid A de Rodez Benavent, Gro O Nygaard, Hanne F Harbo, Siren Tønnesen, Piotr Sowa, Nils I Landrø, Marte Wendel-Haga, Lars Etholm, Kristian B Nilsen, Liv Drolsum, Emilia Kerty, Elisabeth G Celius, Bruno Laeng
INTRODUCTION: In early multiple sclerosis (MS) patients, cognitive changes and fatigue are frequent and troublesome symptoms, probably related to both structural and functional brain changes. Whether there is a common cause of these symptoms in MS is unknown. In theory, an altered regulation of central neuropeptides can lead to changes in regulation of autonomic function, cognitive difficulties, and fatigue. Direct measurements of central neuropeptides are difficult to perform, but measurements of the eye pupil can be used as a reliable proxy of function...
July 2017: Brain and Behavior
https://www.readbyqxmd.com/read/28729900/unravelling-functional-neurology-a-scoping-review-of-theories-and-clinical-applications-in-a-context-of-chiropractic-manual-therapy
#15
REVIEW
Anne-Laure Meyer, Amanda Meyer, Sarah Etherington, Charlotte Leboeuf-Yde
BACKGROUND: Functional Neurology (FN), a seemingly attractive treatment approach used by some chiropractors, proposes to have an effect on a multitude of conditions but some of its concepts are controversial. OBJECTIVES AND DESIGN: A scoping review was performed to describe, in the context of chiropractic manual therapy, 1) the FN theories, and 2) its clinical applications (i.e. its indications, examination procedures, treatment modalities, treatment plans, and clinical outcomes) using four sources: i) one key textbook, ii) the scientific peer-reviewed literature, iii) websites from chiropractors using FN, and iv) semi-structured interviews of chiropractors using FN...
2017: Chiropractic & Manual Therapies
https://www.readbyqxmd.com/read/28729893/mechanically-and-electrically-robust-self-assembled-monolayers-for-large-area-tunneling-junctions
#16
Yanxi Zhang, Xinkai Qiu, Pavlo Gordiichuk, Saurabh Soni, Theodorus L Krijger, Andreas Herrmann, Ryan C Chiechi
This paper examines the relationship between mechanical deformation and the electronic properties of self-assembled monolayers (SAMs) of the oligothiophene 4-([2,2':5',2″:5″,2‴-quaterthiophen]-5-yl)butane-1-thiol (T4C4) in tunneling junctions using conductive probe atomic force microscopy (CP-AFM) and eutectic Ga-In (EGaIn). We compared shifts in conductivity, transition voltages of T4C4 with increasing AFM tip loading force to alkanethiolates. While these shifts result from an increasing tilt angle from penetration of the SAM by the AFM tip for the latter, we ascribe them to distortions of the π system present in T4C4, which is more mechanically robust than alkanethiolates of comparable length; SAMs comprising T4C4 shows about five times higher Young's modulus than alkanethiolates...
July 13, 2017: Journal of Physical Chemistry. C, Nanomaterials and Interfaces
https://www.readbyqxmd.com/read/28729843/is-a-transdisciplinary-theory-of-engagement-in-organized-settings-possible-a-concept-analysis-of-the-literature-on-employee-engagement-consumer-engagement-and-patient-engagement
#17
REVIEW
Guendalina Graffigna
Organizations are experiencing increased competition, disruptive innovation, and continuous changes in their social and economic context. Furthermore, the decrease of resources (economic and human) in such a demanding context make it imperative for organizations to find new models and strategies to make their service delivery more sustainable at the economic, environmental and psychological levels. In such a complex scenario the concept of engagement of the individuals involved in organized settings (either as service providers or as final receivers) is a promising lever for innovation...
2017: Frontiers in Psychology
https://www.readbyqxmd.com/read/28729538/geometric-heterogeneity-of-continental-shale-in-the-yanchang-formation-southern-ordos-basin-china
#18
Lihui Li, Beixiu Huang, Yufang Tan, Xiaolong Deng, Yanyan Li, Hu Zheng
Favorable prospects for the exploration of shale gas have been demonstrated in the Ordos Basin, China. Outcrop and core observations indicate that there are abundant laminas in the shale strata, which exert a great influence on hydro-fracture propagation, gas storage and fluid flow. In this study, the continental shale of the Chang 72 Member, collected from the south of Ordos Basin, was investigated to characterize the geometric heterogeneity. Laminas at multiple scales were observed and measured using conventional logging, borehole TV, core analysis, scanning electron microscopy, and the Particle and Crack Analysis System...
July 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28729417/mathematical-modeling-of-tumor-tumor-distant-interactions%C3%A2-supports-a-systemic-control-of-tumor-growth
#19
Sebastien Benzekry, Clare Lamont, Dominique Barbolosi, Lynn Hlatky, Philip Hahnfeldt
Interactions between different tumors within the same organism have major clinical implications, especially in the context of surgery and metastatic disease. Three main explanatory theories (competition, angiogenesis inhibition and proliferation inhibition) have been proposed but precise determinants of the phenomenon remain poorly understood. Here we formalized these theories into mathematical models and performed biological experiments to test them with empirical data. In syngeneic mice bearing two simultaneously implanted tumors, growth of only one of the tumors was significantly suppressed (61% size reduction at day 15, p<0...
July 20, 2017: Cancer Research
https://www.readbyqxmd.com/read/28728997/sepsis-reconsidered-identifying-novel-metrics-for-behavioral-landscape-characterization-with-a-high-performance-computing-implementation-of-an-agent-based-model
#20
Chase Cockrell, Gary An
OBJECTIVES: Sepsis affects nearly 1 million people in the United States per year, has a mortality rate of 28-50% and requires more than $20 billion a year in hospital costs. Over a quarter century of research has not yielded a single reliable diagnostic test or a directed therapeutic agent for sepsis. Central to this insufficiency is the fact that sepsis remains a clinical/physiological diagnosis representing a multitude of molecularly heterogeneous pathological trajectories. Advances in computational capabilities offered by High Performance Computing (HPC) platforms call for an evolution in the investigation of sepsis to attempt to define the boundaries of traditional research (bench, clinical and computational) through the use of computational proxy models...
July 17, 2017: Journal of Theoretical Biology
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