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https://www.readbyqxmd.com/read/28750400/a-dopamine-hypothesis-of-autism-spectrum-disorder
#1
Denis Pavăl
Autism spectrum disorder (ASD) comprises a group of neurodevelopmental disorders characterized by social deficits and stereotyped behaviors. While several theories have emerged, the pathogenesis of ASD remains unknown. Although studies report dopamine signaling abnormalities in autistic patients, a coherent dopamine hypothesis which could link neurobiology to behavior in ASD is currently lacking. In this paper, we present such a hypothesis by proposing that autistic behavior arises from dysfunctions in the midbrain dopaminergic system...
July 28, 2017: Developmental Neuroscience
https://www.readbyqxmd.com/read/28750347/global-synchronization-in-finite-time-for-fractional-order-neural-networks-with-discontinuous-activations-and-time-delays
#2
Xiao Peng, Huaiqin Wu, Ka Song, Jiaxin Shi
This paper is concerned with the global Mittag-Leffler synchronization and the synchronization in finite time for fractional-order neural networks (FNNs) with discontinuous activations and time delays. Firstly, the properties with respect to Mittag-Leffler convergence and convergence in finite time, which play a critical role in the investigation of the global synchronization of FNNs, are developed, respectively. Secondly, the novel state-feedback controller, which includes time delays and discontinuous factors, is designed to realize the synchronization goal...
July 10, 2017: Neural Networks: the Official Journal of the International Neural Network Society
https://www.readbyqxmd.com/read/28750319/theoretically-obtained-insight-into-the-mechanism-and-dioxetanone-species-responsible-for-the-singlet-chemiexcitation-of-coelenterazine
#3
Chun-Gang Min, Paulo J O Ferreira, Luís Pinto da Silva
Coelenterazine is a widespread bioluminescent substrate for a diverse set of marine species. Moreover, its imidazopyrazinone core is present in eight phyla of bioluminescent organisms. Given their very attractive intrinsic properties, these bioluminescent systems have been used in bioimaging, photodynamic therapy of cancer, as gene reporter and in sensing applications, among others. While it is known that bioluminescence results from the thermolysis of high-energy dioxetanones, the mechanism and dioxetanone species responsible for the singlet chemiexcitation of Coelenterazine are not fully understood...
July 20, 2017: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/28750306/electrical-characterization-of-c28-fullerene-junctions-formed-with-group-1b-metal-electrodes
#4
Rupan Preet Kaur, Ravinder Singh Sawhney, Derick Engles
We present an atomistic theory of electronic transport through single molecular junctions based on smallest stable fullerene molecule, C28. The electronic properties of single molecular junctions critically depend on the nature of electrode material. The two probe device is modeled by constraining C28 between two semi-infinite metal electrodes, from group 1B of periodic table, copper, silver and gold. We have highlighted the correlated phenomena of resonant conduction and current driven dynamics in molecular junctions using extendend Huckel theory in combination with non equilibrium Green's function framework...
July 19, 2017: Journal of Molecular Graphics & Modelling
https://www.readbyqxmd.com/read/28750285/modelling-food-web-mediated-effects-of-hydrological-variability-and-environmental-flows
#5
REVIEW
Barbara J Robson, Rebecca E Lester, Darren S Baldwin, Nicholas R Bond, Romain Drouart, Robert J Rolls, Darren S Ryder, Ross M Thompson
Environmental flows are designed to enhance aquatic ecosystems through a variety of mechanisms; however, to date most attention has been paid to the effects on habitat quality and life-history triggers, especially for fish and vegetation. The effects of environmental flows on food webs have so far received little attention, despite food-web thinking being fundamental to understanding of river ecosystems. Understanding environmental flows in a food-web context can help scientists and policy-makers better understand and manage outcomes of flow alteration and restoration...
July 17, 2017: Water Research
https://www.readbyqxmd.com/read/28750250/philosophical-and-theoretical-content-of-the-nursing-discipline-in-academic-education-a-critical-interpretive-synthesis
#6
REVIEW
Maria Luisa Rega, Fabia Telaretti, Rosaria Alvaro, Mari Kangasniemi
BACKGROUND: Nursing as clinical practice, management and research are based on nursing philosophy and theory. Thus, the philosophical and theoretical content is required to be incorporated in academic education in order to enable nurses' skills for reflection, analysis, and thinking about the profession. OBJECTIVE: The aim of this review was to describe what is known of the philosophical and theoretical content of the nursing discipline within academic education...
July 13, 2017: Nurse Education Today
https://www.readbyqxmd.com/read/28750245/antecedents-and-outcomes-of-nurses-rest-break-organization-a-scoping-review
#7
REVIEW
Johannes Wendsche, Argang Ghadiri, Amelie Bengsch, Jürgen Wegge
OBJECTIVES: To prevent an accumulation of strain during work and to reduce error risk, many countries have made rest breaks mandatory. In the nursing literature, insufficient rest break organization is often reported. However, the outcomes of nurses' rest break organization and its anteceding factors are less clear. DATA SOURCES: We searched for academic literature on nurses' rest break organization in electronic databases (PubMed, Medline, PsycArticles, PsycINFO, CINAHL)...
July 14, 2017: International Journal of Nursing Studies
https://www.readbyqxmd.com/read/28749995/direction-of-arrival-estimation-of-multipath-signals-using-independent-component-analysis-and-compressive-sensing
#8
Lin Zhao, Jian Xu, Jicheng Ding, Aimeng Liu, Liang Li
Multipath signal is often considered an interference that must be removed. The coherence between multipath and direct component makes it difficult to use conventional direction-of-arrival (DOA) estimation methods in a smart antenna system. This study demonstrates a new multipath signal DOA estimation technique. Unlike the common methods, without decoherence preprocessing, the proposed algorithm first apply a complex fast independent component analysis (cFastICA) algorithm to obtain the steering vectors with multipath information that corresponds to each source signal...
2017: PloS One
https://www.readbyqxmd.com/read/28749826/fathers-needs-and-masculinity-dilemmas-in-a-neonatal-intensive-care-unit-in-denmark
#9
Betty Noergaard, Jette Ammentorp, Jesper Fenger-Gron, Poul-Erik Kofoed, Helle Johannessen, Shelley Thibeau
BACKGROUND: Most healthcare professionals in neonatal intensive care units typically focus on the infants and mothers; fathers often feel powerless and find it difficult to establish a father-child relationship. In family-centered healthcare settings, exploring fathers' experiences and needs is important because men's roles in society, especially as fathers, are changing. PURPOSE: To describe fathers' needs when their infants are admitted to a neonatal intensive care unit and to discuss these needs within a theoretical framework of masculinity to advance understanding and generate meaningful knowledge for clinical practices...
August 2017: Advances in Neonatal Care: Official Journal of the National Association of Neonatal Nurses
https://www.readbyqxmd.com/read/28749664/matildite-contact-with-media-first-principles-study-of-agbis2-surfaces-and-nanoparticle-morphology
#10
Francesc Viñes, Gerasimos Konstantatos, Francesc Illas
Motivated by the interest in AgBiS2 material for solar light harvesting applications, a detailed bulk first principles quantum mechanical of surface properties is presented. Density functional theory based calculations with the Perdew-Burke-Ernzerhof functional have been carried out for different surface orientations and terminations. From the results, two particularly stable facets are predicted to dominate Wulff shaped AgBiS2 nanoparticles. These are the (001) type nonpolar surface and the (111) polar terminations where facets are exposed containing solely Ag or S atoms...
July 27, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28749654/decomposition-mechanism-of-c5f10o-an-environmental-friendly-insulation-medium
#11
Xiaoxing Zhang, Yi Li, Song Xiao, Ju Tang, Shuangshuang Tian, Zaitao Deng
SF6, the most widely used electrical-equipment-insulation gas, has serious greenhouse effects. C5F10O has attracted much attention as an alternative gas in recent two years, but the environmental impact of its decomposition products is unclear. In this work, the decomposition characteristics of C5F10O were studied based on gas chromatography-mass spectrometry and density functional theory. We found that the amount of decomposition products of C5F10O, namely, CF4, C2F6, C3F6, C3F8, C4F10, and C6F14, increased with increased number of discharges...
July 27, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28749603/protection-motivation-theory-in-predicting-intention-to-receive-cervical-cancer-screening-in-rural-chinese-women
#12
Yang Bai, Qing Liu, Xinguang Chen, Yanduo Gao, Huiyun Gong, Xiaodong Tan, Min Zhang, Jiyu Tuo, Yuling Zhang, Qunying Xiang, Fenghua Deng, Guiling Liu
OBJECTIVE: Despite the significance of cervical cancer screening, motivating more women to participate remains a challenge in resource-limited settings. In this study, we tested the protection motivation theory (PMT) in predicting screening intentions. METHODS: Participants were women from Wufeng, a typical rural county in China. Participants (n=3000) with no cervical cancer history were recruited from 10 randomly selected villages. As mediating variables, six PMT constructs (Perceived Risk, Fear Arousal, Perceived Severity, Response Efficacy, Response Cost and Self-Efficacy) were measured using the standardized questionnaire...
July 27, 2017: Psycho-oncology
https://www.readbyqxmd.com/read/28749597/a-structural-model-of-nitro-porphyrin-dyes-based-on-spectroscopy-and-density-functional-theory
#13
Christopher Farley, Amit Aggarwal, Sunaina Singh, Aaron Dolor, Philip To, Alexander Falber, Maxwell Crossley, Charles Michael Drain
Nitro-porphyrins are an important class of commercial dyes with a range of potential applications. The nitro group is known to dramatically affect the photophysics of the porphyrin, but there are few systematic investigations of the contributing factors. To address this deficiency, we present spectroscopic studies of a series of nitro-porphyrins, accompanied by density functional theory calculations to elucidate their structures. In particular, we explore how the positions of the substituents affect the energy levels and nuclear geometry...
July 27, 2017: Journal of Computational Chemistry
https://www.readbyqxmd.com/read/28749554/high-energy-resolution-x-ray-absorption-spectroscopy-for-identification-of-reactive-surface-species-on-supported-single-site-iridium-catalysts
#14
Adam S Hoffman, Dimosthenis Sokaras, Shengjie Zhang, Louise M Debefve, Chia-Yu Fang, Alessandro Gallo, Thomas Kroll, David A Dixon, Simon R Bare, Bruce C Gates
We report high-energy-resolution X-ray absorption spectroscopy detection of ethylene and CO ligands adsorbed on catalytically active iridium centers isolated on zeolite HY and on MgO supports. The data are supported by density functional theory and FEFF X-ray absorption near-edge modelling, together with infrared (IR) spectra. The results demonstrate that high-energy-resolution X-ray absorption spectra near the iridium LIII (2p3/2 ) edge provide clearly ascribable, distinctive signatures of the ethylene and CO ligands and illustrate effects of supports and other ligands...
June 9, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28749541/dynamic-covalent-bond-from-first-principles-diarylbibenzofuranone-structural-electronic-and-oxidation-studies
#15
Gabriel R Schleder, Adalberto Fazzio, Jeverson T Arantes
A structure that can self-heal under standard conditions is a challenge faced nowadays and is one of the most promising areas in smart materials science. This can be achieved by dynamic bonds, of which diarylbibenzofuranone (DABBF) dynamic covalent bond is an appealing solution. In this report, we studied the DABBF bond formation against arylbenzofuranone (ABF) and O2 reaction (autoxidation). Our results show that the barrierless DABBF bond formation is preferred over autoxidation due to the charge transfer process that results in the weakly bonded superoxide...
July 27, 2017: Journal of Computational Chemistry
https://www.readbyqxmd.com/read/28749519/atomic-scale-computational-design-of-hydrophobic-re-surface-doped-al2o3-and-tio2
#16
Kamil Czelej, Marcin Roland Zemła, Piotr Spiewak, Tomasz Wejrzanowski, Krzysztof Jan Kurzydłowski
Intrinsically hydrophobic rare-earth oxides (REOs) have emerged as a robust class of ceramics for a variety of applications. Recently, the hydrophobicity of REOs has been observed experimentally and subsequently scrutinized using electronic structure density functional theory (DFT) calculations. In this work, we applied the DFT method to analyze the possibility of tuning the wettability of commonly used hydrophilic Al2O3 and TiO2 by surface doping with Ce. The calculations indicate that Ce can preferentially segregate to the surface of Al2O3 and TiO2 and form a Ce-rich oxide layer, which is stable under a wide range of oxygen chemical potentials...
July 27, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28749518/the-mechanism-and-regioselectivities-of-nhc-nickel-ii-hydride-catalyzed-cycloisomerization-of-dienes-a-computational-study
#17
Yuan Gao, K N Houk, Chun-Yu Ho, Xin Hong
Transition metal-catalyzed hydroalkenylation is widely applied in organic synthesis to construct carbon-carbon bonds and synthesize substituted alkenes. In this work, the mechanism and regioselectivities of [(NHC)NiH](+)-catalyzed intramolecular cycloisomerization of dienes are studied by density functional theory (DFT) calculations. Through an initial hydride insertion, [(NHC)NiH](+) reacts with the diene substrate to generate the alkyl nickel species. This alkyl nickel species is the resting state of the catalytic cycle, and the hydroalkenylation reaction involves sequential olefin insertion and β-hydride transfer...
July 27, 2017: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/28749516/computational-prediction-of-high-methane-storage-capacity-in-v-mof-74
#18
Seokwon Hyeon, Young-Chul Kim, Jihan Kim
The methane adsorption properties in M-MOF-74 (M = Mg, Ti, V, Cr, Mn, Co, Ni, Cu, and Zn) were investigated for potential adsorbed natural gas (ANG) vehicle applications. In particular, density functional theory (DFT) simulations were conducted to derive the force field parameters that were used in the grand canonical Monte Carlo (GCMC) simulations to obtain the methane adsorption isotherm curves. Our results indicate that commonly used DFT exchange correlation functionals (e.g. vdW-DF, vdW-DF2, PBE+D2) overestimated the methane binding strength to the metal sites, leading to inaccurate description of the adsorption properties...
July 27, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28749457/the-theory-of-disappearing-microbiota-and-the-epidemics-of-chronic-diseases
#19
Martin J Blaser
In recent decades, the incidence of many apparently unrelated chronic diseases has markedly increased. Here, I theorize that losses of particular bacterial species of our ancestral microbiota have altered the context in which immunological, metabolic and cognitive development occur in early life, which results in increased disease. This ominous trend suggests that we must refocus efforts to understand and reverse the underlying circumstances that are responsible for our disappearing microbiota.
July 27, 2017: Nature Reviews. Immunology
https://www.readbyqxmd.com/read/28749441/stages-of-behavioral-change-for-reducing-sodium-intake-in-korean-consumers-comparison-of-characteristics-based-on-social-cognitive-theory
#20
So-Hyun Ahn, Jong Sook Kwon, Kyungmin Kim, Hye-Kyeong Kim
High sodium intake increases the risk of cardiovascular disease. Given the importance of behavioral changes to reducing sodium intake, this study aims to investigate the stages of change and the differences in cognitive and behavioral characteristics by stage in Korean consumers. Adult participants (N = 3892) completed a questionnaire on the stages of behavioral change, recognition of social efforts, outcome expectancy, barriers to practice, nutrition knowledge and dietary behaviors, and self-efficiency related to reduced sodium intake...
July 27, 2017: Nutrients
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