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https://www.readbyqxmd.com/read/28222198/algorithmic-design-of-a-noise-resistant-and-efficient-closed-loop-deep-brain-stimulation-system-a-computational-approach
#1
Sofia D Karamintziou, Ana Luísa Custódio, Brigitte Piallat, Mircea Polosan, Stéphan Chabardès, Pantelis G Stathis, George A Tagaris, Damianos E Sakas, Georgia E Polychronaki, George L Tsirogiannis, Olivier David, Konstantina S Nikita
Advances in the field of closed-loop neuromodulation call for analysis and modeling approaches capable of confronting challenges related to the complex neuronal response to stimulation and the presence of strong internal and measurement noise in neural recordings. Here we elaborate on the algorithmic aspects of a noise-resistant closed-loop subthalamic nucleus deep brain stimulation system for advanced Parkinson's disease and treatment-refractory obsessive-compulsive disorder, ensuring remarkable performance in terms of both efficiency and selectivity of stimulation, as well as in terms of computational speed...
2017: PloS One
https://www.readbyqxmd.com/read/28221998/reduction-of-assessment-time-for-stroke-related-impairments-using-robotic-evaluation
#2
Sayyed Mostafa Mostafavi, Stephen H Scott, Sean P Dukelow, Parvin Mousavi
Robotic technologies can provide objective, reliable tools for assessing a broad range of sensory, motor and cognitive functions. However, as additional tasks are developed on these platforms, the time necessary to assess a patient increases. In this paper, we present a hierarchical task selection strategy for five tasks that form part of the battery of standard tests performed on the KINARM robotic system. The strategy is built using dependencies derived through three types of analyses: i) nonlinear hierarchical ordering theory is applied to determine the ordering of five tasks; ii) the parameters of all tasks are also ranked using non-linear hierarchical ordering theory; and iii) a modeling technique, fast orthogonal search (FOS), is applied to assess the predictive power of each robotic task for estimation of other task parameters...
February 16, 2017: IEEE Transactions on Neural Systems and Rehabilitation Engineering
https://www.readbyqxmd.com/read/28221835/social-information-on-fear-and-food-drives-animal-grouping-and-fitness
#3
Michael A Gil, Zachary Emberts, Harrison Jones, Colette M St Mary
Empirical studies in select systems suggest that social information-the incidental or deliberate information produced by animals and available to other animals-can fundamentally shape animal grouping behavior. However, to understand the role of social information in animal behavior and fitness, we must establish general theory that quantifies effects of social information across ecological contexts and generates expectations that can be applied across systems. Here we used dynamic state variable modeling to isolate effects of social information about food and predators on grouping behavior and fitness...
March 2017: American Naturalist
https://www.readbyqxmd.com/read/28221348/self-assembly-of-nanoparticles-into-biomimetic-capsid-like-nanoshells
#4
Ming Yang, Henry Chan, Gongpu Zhao, Joong Hwan Bahng, Peijun Zhang, Petr Král, Nicholas A Kotov
Nanoscale compartments are one of the foundational elements of living systems. Capsids, carboxysomes, exosomes, vacuoles and other nanoshells easily self-assemble from biomolecules such as lipids or proteins, but not from inorganic nanomaterials because of difficulties with the replication of spherical tiling. Here we show that stabilizer-free polydispersed inorganic nanoparticles (NPs) can spontaneously organize into porous nanoshells. The association of water-soluble CdS NPs into self-limited spherical capsules is the result of scale-modified electrostatic, dispersion and other colloidal forces...
March 2017: Nature Chemistry
https://www.readbyqxmd.com/read/28220835/effects-of-abiotic-factors-on-ecosystem-health-of-taihu-lake-china-based-on-eco-exergy-theory
#5
Ce Wang, Jun Bi, Brian D Fath
A lake ecosystem is continuously exposed to environmental stressors with non-linear interrelationships between abiotic factors and aquatic organisms. Ecosystem health depicts the capacity of system to respond to external perturbations and still maintain structure and function. In this study, we explored the effects of abiotic factors on ecosystem health of Taihu Lake in 2013, China from a system-level perspective. Spatiotemporal heterogeneities of eco-exergy and specific eco-exergy served as thermodynamic indicators to represent ecosystem health in the lake...
February 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28220682/the-treadmill-of-production-and-the-positional-economy-of-consumption
#6
Dean Curran
The theory of the treadmill of production highlights how the constant search for economic growth leads to advanced economies being stuck on a "treadmill," where their well-being is not improved by economic growth, yet the impacts of this pursuit of growth causes massive, unsustainable environmental damages. In interrogating the specific driving force that keeps the irrational system of the treadmill so powerfully in place, the theory of the treadmill of production focuses on how those who control the production process, corporations, are the primary agents driving the treadmill, while also highlighting how the state and workers generally continue to provide support for the treadmill's continued reproduction...
February 2017: Canadian Review of Sociology, Revue Canadienne de Sociologie
https://www.readbyqxmd.com/read/28220677/toward-a-sociology-of-oceans
#7
John Hannigan
Despite covering around 70 percent of the earth's surface, the ocean has long been ignored by sociology or treated as merely an extension of land-based systems. Increasingly, however, oceans are assuming a higher profile, emerging both as a new resource frontier, a medium for geopolitical rivalry and conflict, and a unique and threatened ecological hot spot. In this article, I propose a new sociological specialty area, the "sociology of oceans" to be situated at the interface between environmental sociology and traditional maritime studies...
February 2017: Canadian Review of Sociology, Revue Canadienne de Sociologie
https://www.readbyqxmd.com/read/28219896/parallel-contagion-phenomenon-of-concordant-mental-disorders-among-married-couples-a-nationwide-cohort-study
#8
Jong-Yi Wang, Ming-Hong Hsieh, Pei-Ching Lin, Chiu-Shong Liu, Jen-De Chen
BACKGROUND: The aggregation of mental disorders in couples, as reported by prior research, indicates the effect of familial environments and warrants attention. However, the concordant categories of mental disorders in couples remain unclear. This study investigated spousal concordance for the category of mental disorders among couples throughout Taiwan by using factors associated with such disorders. METHODS: 5643 couples in the 2002-2013 Taiwan National Health Insurance Research Database were analysed and compared with propensity-matched 5643 non-couples...
February 20, 2017: Journal of Epidemiology and Community Health
https://www.readbyqxmd.com/read/28219243/light-induced-radical-formation-and-isomerization-of-an-aromatic-thiol-in-solution-followed-by-time-resolved-x-ray-absorption-spectroscopy-at-the-sulfur-k-edge
#9
Miguel Ochmann, Inga von Ahnen, Amy A Cordones, Abid Hussain, Jae Hyuk Lee, Kiryong Hong, Katrin Adamczyk, Oriol Vendrell, Tae Kyu Kim, Robert William Schoenlein, Nils Huse
We applied time-resolved sulfur-1s absorption spectroscopy to a model aromatic thiol system as a promising method for tracking chemical reactions in solution. Sulfur-1s absorption spectroscopy allows tracking multiple sulfur species with a time-resolution of ~70 ps. Experimental transient spectra combined with high-level electronic structure theory allow precise identification of a radical and two thione isomers, which are generated upon illumination with 267 nm radiation. Moreover, the regioselectivity of the thione isomerization is explained by resulting radical frontier orbitals...
February 20, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28219039/microwave-dielectric-relaxation-spectroscopy-study-of-propylene-glycol-ethanol-binary-mixtures-temperature-dependence
#10
T Vishwam, Suriya Shihab, V R K Murthy, Ha Sie Tiong, S Sreehari Sastry
Complex dielectric permittivity measurements of propylene glycol (PG) in ethanol at various mole fractions were measured by using open-ended coaxial probe technique at different temperatures in the frequency range 0.02<ν/GHz<20. The dipole moment (μ), excess dipole moment (Δμ),excess permittivity (ε(E)), excess inverse relaxation time(1/τ)(E), Bruggeman parameter (fB), excess Helmholtz energy (ΔF(E)) are determined using experimental data. From the minimum energy based geometry optimization, dipole moments of individual monomers of propylene glycol and ethanol and their binary system have been evaluated theoretically at gaseous state as well as alcoholic medium by using PCM and IEFPCM solvation models from the Hatree-Fock (HF) and Density Functional Theory (DFT-B3LYP) methods with 6-311G* and 6-311G** basis sets...
February 11, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28218848/effect-of-c%C3%AE-c%C3%AE-bond-type-on-the-radical-scavenging-activity-of-hydroxy-stilbenes-theoretical-insights-in-the-gas-and-liquid-phase
#11
Nikolaos Nenadis, Katholiki Stavra
Density functional theory/Becke's 3-parameter hybrid functional combined with the Lee-Yang-Parr correlation functional (DFT/B3LYP) was used to examine the radical scavenging potential of resveratrol, piceatannol, and their dehydro/dihydro counterparts. For this reason, the values of molecular descriptors predicting the hydrogen atom transfer (HAT) and the single electron transfer preceding (SET-PT) or following a proton transfer (SPLET) were computed in the gas and liquid (benzene, water) phase. The double bond, resulting in molecular planarity, was predicted to favor the single hydrogen or electron transfer...
February 20, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28218805/functional-nonredundancy-of-elephants-in-a-disturbed-tropical-forest
#12
Nitin Sekar, Chia-Lo Lee, Raman Sukumar
Conservation efforts are often motivated by the threat of global extinction. Yet if conservationists had more information suggesting that the local extirpation of individual species could lead to undesirable ecological effects, conservationists might more frequently attempt to protect or restore such species across their range even if they are not in danger of global extinction. Scientists have seldom measured or quantitatively predicted the functional consequences of species loss, even for large, extinction-prone species that theory suggests should be functionally unique...
February 20, 2017: Conservation Biology: the Journal of the Society for Conservation Biology
https://www.readbyqxmd.com/read/28218316/theoretical-study-of-hcn-water-interaction-five-dimensional-potential-energy-surfaces
#13
Ernesto Quintas Sánchez, Marie-Lise Dubernet
A new five-dimensional potential energy surface is calculated at the coupled-cluster CCSD(T) level of theory for the HCN-water system, treating both monomers as rigid rotors. The associated methodology, which combines extensive ab initio calculations of moderate accuracy (CCSD(T)/AVDZ) and a fitting procedure involving a much lower angular coverage with more accurate ab initio calculations (CCSD(T)/CBS), is described in detail. This methodology provides a time-saving approach to compute quantitatively accurate potential energy surfaces with reasonable computational effort...
February 20, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28218249/complexity-variability-assessment-of-nonlinear-time-varying-cardiovascular-control
#14
Gaetano Valenza, Luca Citi, Ronald G Garcia, Jessica Noggle Taylor, Nicola Toschi, Riccardo Barbieri
The application of complex systems theory to physiology and medicine has provided meaningful information about the nonlinear aspects underlying the dynamics of a wide range of biological processes and their disease-related aberrations. However, no studies have investigated whether meaningful information can be extracted by quantifying second-order moments of time-varying cardiovascular complexity. To this extent, we introduce a novel mathematical framework termed complexity variability, in which the variance of instantaneous Lyapunov spectra estimated over time serves as a reference quantifier...
February 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28217892/animal-pee-in-the-sea-consumer-mediated-nutrient-dynamics-in-the-world-s-changing-oceans
#15
REVIEW
Jacob E Allgeier, Deron E Burkepile, Craig A Layman
Humans have drastically altered the abundance of animals in marine ecosystems via exploitation. Reduced abundance can destabilize food webs, leading to cascading indirect effects that dramatically reorganize community structure and shift ecosystem function. However, the additional implications of these top-down changes for biogeochemical cycles via consumer-mediated nutrient dynamics (CND) are often overlooked in marine systems, particularly in coastal areas. Here, we review research that underscores the importance of this bottom-up control at local, regional, and global scales in coastal marine ecosystems, and the potential implications of anthropogenic change to fundamentally alter these processes...
February 20, 2017: Global Change Biology
https://www.readbyqxmd.com/read/28217739/grounded-and-embodied-mathematical-cognition-promoting-mathematical-insight-and-proof-using-action-and-language
#16
Mitchell J Nathan, Candace Walkington
We develop a theory of grounded and embodied mathematical cognition (GEMC) that draws on action-cognition transduction for advancing understanding of how the body can support mathematical reasoning. GEMC proposes that participants' actions serve as inputs capable of driving the cognition-action system toward associated cognitive states. This occurs through a process of transduction that promotes valuable mathematical insights by eliciting dynamic depictive gestures that enact spatio-temporal properties of mathematical entities...
2017: Cogn Res Princ Implic
https://www.readbyqxmd.com/read/28216800/treatment-of-depression-from-a-self-regulation-perspective-basic-concepts-and-applied-strategies-in-self-system-therapy
#17
Timothy J Strauman, Kari M Eddington
Self-regulation models of psychopathology provide a theory-based, empirically supported framework for developing psychotherapeutic interventions that complement and extend current cognitive-behavioral models. However, many clinicians are only minimally familiar with the psychology of self-regulation. The aim of the present manuscript is twofold. First, we provide an overview of self-regulation as a motivational process essential to well-being and introduce two related theories of self-regulation which have been applied to depression...
February 2017: Cognitive Therapy and Research
https://www.readbyqxmd.com/read/28215288/applications-of-dynamic-systems-theory-to-cognition-and-development-new-frontiers
#18
S Perone, V R Simmering
A central goal in developmental science is to explain the emergence of new behavioral forms. Researchers consider potential sources of behavioral change depending partly on their theoretical perspective. This chapter reviews one perspective, dynamic systems theory, which emphasizes the interactions among multiple components to drive behavior and developmental change. To illustrate the central concepts of dynamic systems theory, we describe empirical and computational studies from a range of domains, including motor development, the Piagetian A-not-B task, infant visual recognition, visual working memory capacity, and language learning...
2017: Advances in Child Development and Behavior
https://www.readbyqxmd.com/read/28214530/automaton-model-of-protein-dynamics-of-conformational-and-functional-states
#19
REVIEW
Andrei Khrennikov, Ekaterina Yurova
In this conceptual paper we propose to explore the analogy between ontic/epistemic description of quantum phenomena and interrelation between dynamics of conformational and functional states of proteins. Another new idea is to apply theory of automata to model the latter dynamics. In our model protein's behavior is modeled with the aid of two dynamical systems, ontic and epistemic, which describe evolution of conformational and functional states of proteins, respectively. The epistemic automaton is constructed from the ontic automaton on the basis of functional (observational) equivalence relation on the space of ontic states...
February 15, 2017: Progress in Biophysics and Molecular Biology
https://www.readbyqxmd.com/read/28214073/older-adults-with-ptsd-brief-state-of-research-and-evidence-based-psychotherapy-case-illustration
#20
Joan M Cook, Elissa McCarthy, Steven R Thorp
Although lifetime exposure to potentially traumatic events among older adults is fairly high, rates of full-blown post-traumatic stress disorder (PTSD) are estimated at about 4.5%, a rate lower than that for middle-aged and young adults. Nevertheless, PTSD seems to be an under-recognized and under-treated condition in older adults. Assessment and treatment can be challenging in this population for various reasons, including potential cognitive or sensory decline and comorbid mental and physical disorders. This article provides highlights of the empirical research on PTSD in late life, including information on its effects on cognition and physical health...
January 4, 2017: American Journal of Geriatric Psychiatry
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