RADIATION-RESISTANT FIBER OPTIC STRAIN SENSORS FOR SNS TARGET INSTRUMENTATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blokland, Willem; Bryan, Jeff; Riemer, Bernie

2016-01-01

Measurement of stresses and strains in the mercury tar-get vessel of the Spallation Neutron Source (SNS) is important to understand the structural dynamics of the target. This work reports the development of radiation-resistant fiber optic strain sensors for the SNS target in-strumentation.

Quantum size and electric field modulations on electronic structures of SnS2/BN hetero-multilayers

NASA Astrophysics Data System (ADS)

Xia, Congxin; Zhang, Qian; Xiao, Wenbo; Du, Juan; Li, Xueping; Li, Jingbo

2018-05-01

Through first-principles calculations, we study the stability, band structures, band alignment, and interlayer charge transfer of SnS2/BN hetero-multilayers, considering quantum size and electric field effects. We find that SnS2/BN hetero-multilayers possess the characteristics of direct band structures and type-II band alignment. Moreover, increasing the BN layer number can decrease the band gap value and work function. Additionally, type-II can be tuned to type-I band alignment in the presence of an electric field. These results indicate that the SnS2/BN system is different from that of other BN-based hybrid materials, such as MoS2/BN with type-I band alignment, which is promising for optoelectronic device applications.

Calculations vs. Measurements for Remnant Dose Rates from SNS Spent Structures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Popova, Irina I.; Gallmeier, Franz X.; Trotter, Steven M.

The Spallation Neutron Source (SNS) in Oak Ridge, Tennessee, is an accelerator driven neutron scattering facility for materials research. Presently SNS is capable to operate at 1.4 MW proton beam power incident on a mercury target with a proton beam energy of 1 GeV and 60 Hz repetition rate. SNS target system components are periodically replaced because they reach their end-of-life due to radiation induced material damage. Target vessel, which houses mercury target, is exchanged about two-three times per year and the proton beam window (PBW) is exchanged every two – three years.Each spent structure that leaves the SNS sitemore » requires supporting documentation with radionuclide inventory and dose rate prediction for the time of the transportation. Neutronics analyses are performed, assuming realistic irradiation history and decay case to ensure that the container/package, housing the structure, is compliant with the waste management regulations. Analyses are complex due to geometry, multi-code usage and following data treatment.To validate analyses, measurements of dose rates from the spent target vessel # 13 and PBW module #5 were performed. Neutronics analyses were performed to calculate residual dose rates from both structures for the time of measurements.« less

Brain anatomy alterations associated with Social Networking Site (SNS) addiction

PubMed Central

He, Qinghua; Turel, Ofir; Bechara, Antoine

2017-01-01

This study relies on knowledge regarding the neuroplasticity of dual-system components that govern addiction and excessive behavior and suggests that alterations in the grey matter volumes, i.e., brain morphology, of specific regions of interest are associated with technology-related addictions. Using voxel based morphometry (VBM) applied to structural Magnetic Resonance Imaging (MRI) scans of twenty social network site (SNS) users with varying degrees of SNS addiction, we show that SNS addiction is associated with a presumably more efficient impulsive brain system, manifested through reduced grey matter volumes in the amygdala bilaterally (but not with structural differences in the Nucleus Accumbens). In this regard, SNS addiction is similar in terms of brain anatomy alterations to other (substance, gambling etc.) addictions. We also show that in contrast to other addictions in which the anterior-/ mid- cingulate cortex is impaired and fails to support the needed inhibition, which manifests through reduced grey matter volumes, this region is presumed to be healthy in our sample and its grey matter volume is positively correlated with one’s level of SNS addiction. These findings portray an anatomical morphology model of SNS addiction and point to brain morphology similarities and differences between technology addictions and substance and gambling addictions. PMID:28332625

In-situ sulfuration synthesis of sandwiched spherical tin sulfide/sulfur-doped graphene composite with ultra-low sulfur content

NASA Astrophysics Data System (ADS)

Zhao, Bing; Yang, Yaqing; Wang, Zhixuan; Huang, Shoushuang; Wang, Yanyan; Wang, Shanshan; Chen, Zhiwen; Jiang, Yong

2018-02-01

SnS is widely studied as anode materials since of its superior structural stability and physicochemical property comparing with other Sn-based composites. Nevertheless, the inconvenience of phase morphology control and excessive consumption of sulfur sources during synthesis hinder the scalable application of SnS nanocomposites. Herein, we report a facile in-situ sulfuration strategy to synthesize sandwiched spherical SnS/sulfur-doped graphene (SnS/S-SG) composite. An ultra-low sulfur content with approximately stoichiometric ratio of Sn:S can effectively promote the sulfuration reaction of SnO2 to SnS and simultaneous sulfur-doping of graphene. The as-prepared SnS/S-SG composite shows a three-dimensional interconnected spherical structure as a whole, in which SnS nanoparticles are sandwiched between the multilayers of graphene sheets forming a hollow sphere. The sandwiched sphere structure and high S doping amount can improve the binding force between SnS and graphene, as well as the structural stability and electrical conductivity of the composite. Thus, a high reversibility of conversion reaction, promising specific capacity (772 mAh g-1 after 100 cycles at 0.1 C) and excellent rate performance (705 and 411 mAh g-1 at 1 C and 10 C, respectively) are exhibited in the SnS/S-SG electrode, which are much higher than that of the SnS/spherical graphene synthesized by traditional post-sulfuration method.

Thickness-dependent structure and properties of SnS2 thin films prepared by atomic layer deposition

NASA Astrophysics Data System (ADS)

Seo, Wondeok; Shin, Seokyoon; Ham, Giyul; Lee, Juhyun; Lee, Seungjin; Choi, Hyeongsu; Jeon, Hyeongtag

2017-03-01

Tin disulfide (SnS2) thin films were deposited by a thermal atomic layer deposition (ALD) method at low temperatures. The physical, chemical, and electrical characteristics of SnS2 were investigated as a function of the film thickness. SnS2 exhibited a (001) hexagonal plane peak at 14.9° in the X-ray diffraction (XRD) results and an A1g peak at 311 cm-1 in the Raman spectra. These results demonstrate that SnS2 thin films grown at 150 °C showed a crystalline phase at film thicknesses above 11.2 nm. The crystallinity of the SnS2 thin films was evaluated by a transmission electron microscope (TEM). The X-ray photoelectron spectroscopy (XPS) analysis revealed that SnS2 consisted of Sn4+ and S2- valence states. Both the optical band gap and the transmittance of SnS2 decreased as the film thickness increased. The band gap of SnS2 decreased from 3.0 to 2.4 eV and the transmittance decreased from 85 to 32% at a wavelength of 400 nm. In addition, the resistivity of the thin film SnS2 decreased from 1011 to 106 Ω·cm as the film thickness increased.

Optimizing acoustical conditions for speech intelligibility in classrooms

NASA Astrophysics Data System (ADS)

Yang, Wonyoung

High speech intelligibility is imperative in classrooms where verbal communication is critical. However, the optimal acoustical conditions to achieve a high degree of speech intelligibility have previously been investigated with inconsistent results, and practical room-acoustical solutions to optimize the acoustical conditions for speech intelligibility have not been developed. This experimental study validated auralization for speech-intelligibility testing, investigated the optimal reverberation for speech intelligibility for both normal and hearing-impaired listeners using more realistic room-acoustical models, and proposed an optimal sound-control design for speech intelligibility based on the findings. The auralization technique was used to perform subjective speech-intelligibility tests. The validation study, comparing auralization results with those of real classroom speech-intelligibility tests, found that if the room to be auralized is not very absorptive or noisy, speech-intelligibility tests using auralization are valid. The speech-intelligibility tests were done in two different auralized sound fields---approximately diffuse and non-diffuse---using the Modified Rhyme Test and both normal and hearing-impaired listeners. A hybrid room-acoustical prediction program was used throughout the work, and it and a 1/8 scale-model classroom were used to evaluate the effects of ceiling barriers and reflectors. For both subject groups, in approximately diffuse sound fields, when the speech source was closer to the listener than the noise source, the optimal reverberation time was zero. When the noise source was closer to the listener than the speech source, the optimal reverberation time was 0.4 s (with another peak at 0.0 s) with relative output power levels of the speech and noise sources SNS = 5 dB, and 0.8 s with SNS = 0 dB. In non-diffuse sound fields, when the noise source was between the speaker and the listener, the optimal reverberation time was 0.6 s with SNS = 4 dB and increased to 0.8 and 1.2 s with decreased SNS = 0 dB, for both normal and hearing-impaired listeners. Hearing-impaired listeners required more early energy than normal-hearing listeners. Reflective ceiling barriers and ceiling reflectors---in particular, parallel front-back rows of semi-circular reflectors---achieved the goal of decreasing reverberation with the least speech-level reduction.

Nucleation and growth mechanism of 2D SnS2 by chemical vapor deposition: initial 3D growth followed by 2D lateral growth

NASA Astrophysics Data System (ADS)

Zhang, Haodong; van Pelt, Thomas; Nalin Mehta, Ankit; Bender, Hugo; Radu, Iuliana; Caymax, Matty; Vandervorst, Wilfried; Delabie, Annelies

2018-07-01

Tin disulfide (SnS2) is a n-type semiconductor with a hexagonally layered crystal structure and has promising applications in nanoelectronics, optoelectronics and sensors. Such applications require the deposition of SnS2 with controlled crystallinity and thickness control at monolayer level on large area substrate. Here, we investigate the nucleation and growth mechanism of two-dimensional (2D) SnS2 by chemical vapor deposition (CVD) using SnCl4 and H2S as precursors. We find that the growth mechanism of 2D SnS2 is different from the classical layer-by-layer growth mode, by which monolayer-thin 2D transition metal dichalcogenides can be formed. In the initial nucleation stage, isolated 2D SnS2 domains of several monolayers high are formed. Next, 2D SnS2 crystals grow laterally while keeping a nearly constant height until layer closure is achieved, due to the higher reactivity of SnS2 crystal edges than basal planes. We infer that the thickness of the 2D SnS2 crystals is determined by the height of initial SnS2 islands. After layer closure, SnS2 grows on grain boundaries and results in 3D growth mode, accompanied by spiral growth. Our findings suggest an approach to prepare 2D SnS2 with a controlled thickness of several monolayers and add more knowledge on the nucleation and growth mechanism of 2D materials.

KF addition to Cu2SnS3 thin films prepared by sulfurization process

NASA Astrophysics Data System (ADS)

Nakashima, Mitsuki; Fujimoto, Junya; Yamaguchi, Toshiyuki; Sasano, Junji; Izaki, Masanobu

2017-04-01

Cu2SnS3 thin films were fabricated by sulfurization with KF addition and applied to photovoltaic devices. Two methods, two-stage annealing and the use of four-layer precursors, were employed, and the quantity of NaF and KF and the annealing temperature were changed. By electron probe microanalysis (EPMA), the Cu/Sn mole ratio was found to range from 0.81 to 1.51. The X-ray diffraction (XRD) patterns and Raman spectra indicated that the fabricated thin films had a monoclinic Cu2SnS3 structure. The Cu2SnS3 thin films fabricated by two-stage annealing had a close-packed structure and a pinhole-free surface morphology. The best solar cell in this study showed V oc of 293 mV, which surpassed the previously reported value.

Synthesis of SnS2/SnS fullerene-like nanoparticles: a superlattice with polyhedral shape.

PubMed

Hong, Sung You; Popovitz-Biro, Ronit; Prior, Yehiam; Tenne, Reshef

2003-08-27

Tin disulfide pellets were laser ablated in an inert gas atmosphere, and closed cage fullerene-like (IF) nanoparticles were produced. The nanoparticles had various polyhedra and short tubular structures. Some of these forms contained a periodic pattern of fringes resulting in a superstructure. These patterns could be assigned to a superlattice created by periodic stacking of layered SnS(2) and SnS. Such superlattices are reminiscent of misfit layer compounds, which are known to form tubular morphologies. This mechanism adds up to the established mechanism for IF formation, namely, the annihilation of reactive dangling bonds at the periphery of the nanoparticles. Additionally, it suggests that one of the driving forces to form tubules in misfit compounds is the annihilation of dangling bonds at the rim of the layered structure.

Electrochemical synthesis of nanostructured Se-doped SnS: Effect of Se-dopant on surface characterizations

NASA Astrophysics Data System (ADS)

Kafashan, Hosein; Azizieh, Mahdi; Balak, Zohre

2017-07-01

SnS1-xSex nanostructures with different Se-dopant concentrations were deposited on fluorine doped tin oxide (FTO) substrate through cathodic electrodeposition technique. The pH, temperature, applied potential (E), and deposition time remained were 2.1, 60 °C, -1 V, and 30 min, respectively. SnS1-xSex nanostructures were characterized using X-ray diffraction (XRD), field emission scanning electron microcopy (FESEM), energy dispersive X-ray spectroscopy (EDX), room temperature photoluminescence (PL), and UV-vis spectroscopy. The XRD patterns revealed that the SnS1-xSex nanostructures were polycrystalline with orthorhombic structure. FESEM showed various kinds of morphologies in SnS1-xSex nanostructures due to Se-doping. PL and UV-vis spectroscopy were used to evaluate the optical properties of SnS1-xSex thin films. The PL spectra of SnS1-xSex nanostructures displayed four emission peaks, those are a blue, a green, an orange, and a red emission. UV-vis spectra showed that the optical band gap energy (Eg) of SnS1-xSex nanostructures varied between 1.22-1.65 eV, due to Se-doping.

Characteristics of layered tin disulfide deposited by atomic layer deposition with H2S annealing

NASA Astrophysics Data System (ADS)

Lee, Seungjin; Shin, Seokyoon; Ham, Giyul; Lee, Juhyun; Choi, Hyeongsu; Park, Hyunwoo; Jeon, Hyeongtag

2017-04-01

Tin disulfide (SnS2) has attracted much attention as a two-dimensional (2D) material. A high-quality, low-temperature process for producing 2D materials is required for future electronic devices. Here, we investigate tin disulfide (SnS2) layers deposited via atomic layer deposition (ALD) using tetrakis(dimethylamino)tin (TDMASn) as a Sn precursor and H2S gas as a sulfur source at low temperature (150° C). The crystallinity of SnS2 was improved by H2S gas annealing. We carried out H2S gas annealing at various conditions (250° C, 300° C, 350° C, and using a three-step method). Angle-resolved X-ray photoelectron spectroscopy (ARXPS) results revealed the valence state corresponding to Sn4+ and S2- in the SnS2 annealed with H2S gas. The SnS2 annealed with H2S gas had a hexagonal structure, as measured via X-ray diffraction (XRD) and the clearly out-of-plane (A1g) mode in Raman spectroscopy. The crystallinity of SnS2 was improved after H2S annealing and was confirmed using the XRD full-width at half-maximum (FWHM). In addition, high-resolution transmission electron microscopy (HR-TEM) images indicated a clear layered structure.

Effect of annealing atmosphere on properties of Cu2ZnSn(S,Se)4 thin films

NASA Astrophysics Data System (ADS)

Xue, Yuming; Yu, Bingbing; Li, Wei; Feng, Shaojun; Wang, Yukun; Huang, Shengming; Zhang, Chao; Qiao, Zaixiang

2017-12-01

Earth-abundant Cu2ZnSn(S,Se)4(CZTSSe) thin film photovoltaic absorber layers were fabricated by co-evaporated Cu, ZnS, SnS and Se sources in a vacuum chamber followed by annealing at tubular furnace for 30 min at 550 °C. In this paper, we investigated the metal elements with stoichiometric ratio film to study the effect of annealing conditions of Se, SnS + Se, S and SnS + S atmosphere on the structure, surface morphological, optical and electrical properties of Cu2ZnSn(S,Se)4 thin films respectively. These films were characterized by Inductively Coupled Plasma-Mass Spectrometer, scanning electron microscopy, X-ray diffraction to investigate the composition, morphological and crystal structural properties. The grain size of samples were found to increase after annealing. XRD patterns confirmed the formation of pure polycrystalline CZTSSe thin films at S atmosphere, the optical band gaps are 1.02, 1.05, 1.23, 1.35 eV for Se, SnS + Se, SnS + S and S atmosphere respectively.

Low-Temperature Wafer-Scale Deposition of Continuous 2D SnS2 Films.

PubMed

Mattinen, Miika; King, Peter J; Khriachtchev, Leonid; Meinander, Kristoffer; Gibbon, James T; Dhanak, Vin R; Räisänen, Jyrki; Ritala, Mikko; Leskelä, Markku

2018-04-19

Semiconducting 2D materials, such as SnS 2 , hold immense potential for many applications ranging from electronics to catalysis. However, deposition of few-layer SnS 2 films has remained a great challenge. Herein, continuous wafer-scale 2D SnS 2 films with accurately controlled thickness (2 to 10 monolayers) are realized by combining a new atomic layer deposition process with low-temperature (250 °C) postdeposition annealing. Uniform coating of large-area and 3D substrates is demonstrated owing to the unique self-limiting growth mechanism of atomic layer deposition. Detailed characterization confirms the 1T-type crystal structure and composition, smoothness, and continuity of the SnS 2 films. A two-stage deposition process is also introduced to improve the texture of the films. Successful deposition of continuous, high-quality SnS 2 films at low temperatures constitutes a crucial step toward various applications of 2D semiconductors. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Preparation and characterization of Cu2SnS3 thin films by electrodeposition

NASA Astrophysics Data System (ADS)

Patel, Biren; Narasimman, R.; Pati, Ranjan K.; Mukhopadhyay, Indrajit; Ray, Abhijit

2018-05-01

Cu2SnS3 thin films were electrodeposited on F:SnO2/Glass substrates at room temperature by using aqueous solution. Copper and tin were first electrodeposited from single bath and post annealed in the presence of sulphur atmosphere to obtain the Cu2SnS3 phase. The Cu2SnS3 phase with preferred orientation along the (112) crystal direction grows to greater extent by the post annealing of the film. Raman analysis confirms the monoclinic crystal structure of Cu2SnS3 with principle mode of vibration as A1 (symmetric breathing mode) corresponding to the band at 291 cm-1. It also reveals the benign coexistence of orthorhombic Cu3SnS4 and Cu2SnS7 phases. Optical properties of the film show direct band gap of 1.25 eV with a high absorption coefficient of the order of 104 cm-1 in the visible region. Photo activity of the electrodeposited film was established in two electrode photoelectro-chemical cell, where an open circuit voltage of 91.6 mV and a short circuit current density of 10.6 µA/cm2 were recorded. Fabrication of Cu2SnS3 thin film heterojunction solar cell is underway.

Combinatorial development of Cu2SnS3 as an earth abundant photovoltaic absorber

NASA Astrophysics Data System (ADS)

Baranowski, Lauryn L.

The development of high efficiency, earth abundant photovoltaic absorbers is critical if photovoltaics are to be implemented on the TW scale. Although traditional thin films absorbers such as Cu(In,Ga)Se2 and CdTe have achieved over 20% device efficiencies, the ultimately scalability of these devices may be limited by elemental scarcity and toxicity issues. To date, the most successful earth abundant thin film absorber is Cu2ZnSn(S,Se) 4, which has achieved 12.6% efficiency as of 2014. However, chemical complexity and disorder issues with this material have made the path to higher efficiency CZTSSe devices unclear. As a result, many researchers are now exploring alternative earth abundant absorber materials. In this thesis, we apply our "rapid development" methodology to the exploration of alternative photovoltaic absorbers. The rapid development (RD) methodology, consisting of exploration, research, and development stages, uses complementary theory and experiment to assess candidate materials and down-select in each stage. The overall result is that, in the time span of ~2-3 years, we are able to rapidly go from tens of possible absorber materials to 1-2 working PV device prototypes. Here, we demonstrate the RD approach as applied to the Cu-Sn-S system. We begin our investigation of the Cu-Sn-S system by evaluating the thermodynamic stability, electrical transport, electronic structure, and optical and defect properties of candidate materials using complementary theory and experiment. We find that Cu2SnS3 is the most promising absorber candidate because of its strong optical absorption, tunable doping, and wide stability range. Our other candidate compounds suffer from serious flaws that preclude them from being successful photovoltaic absorbers, including too high experimental conductivity (Cu4SnS4), or poor hole transport and low absorption coefficient (Cu4Sn7S16). Next, we investigate the doping and defect physics of Cu2SnS 3. We identify the origins of the changes in doping in sputtered cubic Cu2SnS3 thin films using combinatorial experiments and first-principles theory. High S chemical potential during deposition decreases the enthalpy of formation of Cu vacancies, which are the dominant acceptor defect in Cu2SnS3. Unexpectedly, under Cu-rich conditions, alloying with an isostructural (cubic) metallic Cu3SnS4 phase occurs, causing high levels of p-type doping. Both of these effects lead to undesirably high electrical conductivity, thus Cu2SnS 3 films must be grown both S- and Cu-poor in order to achieve moderate hole concentrations. To understand the effects of structural disorder on the transport properties in Cu2SnS3 we develop synthetic techniques to control this disorder, and observe improvements in the majority carrier (hole) transport. However, when the minority carrier (electron) transport was investigated, minimal differences were observed between the ordered and disordered Cu 2SnS3. By combining these results with first-principles and Monte Carlo theoretical calculations, we are able to conclude that even ostensibly "ordered" Cu2SnS3 displays minority carrier transport properties corresponding to the disordered structure. The presence of extended planar defects in all samples, observed in TEM imaging, suggests that disorder is present even when it is not detectable using traditional structural characterization methods. Lastly, we attempt to integrate our Cu2SnS3 films into photovoltaic devices, which requires translating our growth techniques to conductive substrates. We survey a wide range of possible conductive substrates, but are not able to find a suitable back contact for Cu2SnS 3 device integration, due to issues such as secondary phase formation and delamination. From a survey of successful Cu2SnS3 device literature, we are able to conclude that the issue may lie with our binary sputtering method in which the ternary compound formation and the film growth occur simultaneously. At the conclusion of this study, we eliminated Cu2SnS as an absorber candidate for future development. However, the two main issues we encountered (eliminating structural disorder and difficulty growing on conductive back contacts) may both be related to our binary sputtering technique. We expect that interest in Cu2SnS3-based photovoltaics will continue to grow, and that further scientific understanding may shed light on our particular difficulties. In the future, the RD methodology has the potential to greatly accelerate the discovery and development of non-traditional thin film absorbers, and may enable high impact material breakthroughs.

Photo-thermoelectric properties of SnS nanocrystals with orthorhombic layered structure

NASA Astrophysics Data System (ADS)

Hyun, Cheol-Min; Choi, Jeong-Hun; Lee, Myoung-Jae; Ahn, Ji-Hoon

2017-07-01

The photo-thermoelectric properties of SnS nanocrystals, two-dimensional materials with an orthorhombic symmetry, were investigated using a focused laser scanning method. The SnS nanocrystals were synthesized by a vapor transport method, and their fundamental material and electrical properties were investigated. Upon shining a laser onto the SnS channel region under a positive source-drain bias, a positive photocurrent was observed due to photo-excited electron-hole pairs. On the other hand, when this external electric field was not applied, a strong photocurrent was observed within the metal electrode region rather than at the metal-semiconductor interface, which indicated that the major mechanism for the photocurrent under zero external bias was a photo-induced thermoelectric effect rather than a photovoltaic effect. Moreover, the Seebeck coefficient of the SnS nanocrystal device was approximately 1735 μV/K, which is 3.5 times larger than that of its bulk counterpart.

Face-to-face or not-to-face: A technology preference for communication.

PubMed

Jaafar, Noor Ismawati; Darmawan, Bobby; Mohamed Ariffin, Mohd Yahya

2014-11-01

This study employed the Model of Technology Preference (MTP) to explain the relationship of the variables as the antecedents of behavioral intention to adopt a social networking site (SNS) for communication. Self-administered questionnaires were distributed to SNS account users using paper-based and web-based surveys that led to 514 valid responses. The data were analyzed using structural equation modeling (SEM). The results show that two out of three attributes of the attribute-based preference (ATRP) affect attitude-based preference (ATTP). The data support the hypotheses that perceived enjoyment and social presence are predictors of ATTP. In this study, the findings further indicated that ATTP has no relationship with the behavioral intention of using SNS, but it has a relationship with the attitude of using SNS. SNS development should provide features that ensure enjoyment and social presence for users to communicate instead of using the traditional face-to-face method of communication.

Negative consequences from heavy social networking in adolescents: The mediating role of fear of missing out.

PubMed

Oberst, Ursula; Wegmann, Elisa; Stodt, Benjamin; Brand, Matthias; Chamarro, Andrés

2017-02-01

Social networking sites (SNS) are especially attractive for adolescents, but it has also been shown that these users can suffer from negative psychological consequences when using these sites excessively. We analyze the role of fear of missing out (FOMO) and intensity of SNS use for explaining the link between psychopathological symptoms and negative consequences of SNS use via mobile devices. In an online survey, 1468 Spanish-speaking Latin-American social media users between 16 and 18 years old completed the Hospital Anxiety and Depression Scale (HADS), the Social Networking Intensity scale (SNI), the FOMO scale (FOMOs), and a questionnaire on negative consequences of using SNS via mobile device (CERM). Using structural equation modeling, it was found that both FOMO and SNI mediate the link between psychopathology and CERM, but by different mechanisms. Additionally, for girls, feeling depressed seems to trigger higher SNS involvement. For boys, anxiety triggers higher SNS involvement. Copyright © 2016 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

The Mediating Roles of Upward Social Comparison and Self-esteem and the Moderating Role of Social Comparison Orientation in the Association between Social Networking Site Usage and Subjective Well-Being.

PubMed

Wang, Jin-Liang; Wang, Hai-Zhen; Gaskin, James; Hawk, Skyler

2017-01-01

The increased pervasiveness of social media use has raised questions about potential effects on users' subjective well-being, with studies reaching contrasting conclusions. To reconcile these discrepancies and shed new light on this phenomenon, the current study examined: (1) whether upward social comparison and self-esteem mediate the association between social networking site (SNS) usage and users' subjective well-being, and (2) whether the association between SNS usage and upward social comparison is moderated by users' social comparison orientation. Data from 696 participants were collected. Structural equation modeling revealed that upward social comparison and self-esteem mediated the relationship between SNS usage and users' subjective well-being. We found that social comparison orientation moderated the association between passive SNS usage and users' upward social comparison. Specifically, social comparison orientation strengthened the association between passive SNS usage and upward social comparison. The results might suggest a process through which passive SNS usage is related to subjective well-being, and identify a context under which these associations may differ.

The Mediating Roles of Upward Social Comparison and Self-esteem and the Moderating Role of Social Comparison Orientation in the Association between Social Networking Site Usage and Subjective Well-Being

PubMed Central

Wang, Jin-Liang; Wang, Hai-Zhen; Gaskin, James; Hawk, Skyler

2017-01-01

The increased pervasiveness of social media use has raised questions about potential effects on users’ subjective well-being, with studies reaching contrasting conclusions. To reconcile these discrepancies and shed new light on this phenomenon, the current study examined: (1) whether upward social comparison and self-esteem mediate the association between social networking site (SNS) usage and users’ subjective well-being, and (2) whether the association between SNS usage and upward social comparison is moderated by users’ social comparison orientation. Data from 696 participants were collected. Structural equation modeling revealed that upward social comparison and self-esteem mediated the relationship between SNS usage and users’ subjective well-being. We found that social comparison orientation moderated the association between passive SNS usage and users’ upward social comparison. Specifically, social comparison orientation strengthened the association between passive SNS usage and upward social comparison. The results might suggest a process through which passive SNS usage is related to subjective well-being, and identify a context under which these associations may differ. PMID:28553256

2-Aminobenzimidazoles as potent Aurora kinase inhibitors.

PubMed

Zhong, Min; Bui, Minna; Shen, Wang; Baskaran, Subramanian; Allen, Darin A; Elling, Robert A; Flanagan, W Michael; Fung, Amy D; Hanan, Emily J; Harris, Shannon O; Heumann, Stacey A; Hoch, Ute; Ivy, Sheryl N; Jacobs, Jeffrey W; Lam, Stuart; Lee, Heman; McDowell, Robert S; Oslob, Johan D; Purkey, Hans E; Romanowski, Michael J; Silverman, Jeffrey A; Tangonan, Bradley T; Taverna, Pietro; Yang, Wenjin; Yoburn, Josh C; Yu, Chul H; Zimmerman, Kristin M; O'Brien, Tom; Lew, Willard

2009-09-01

This Letter describes the discovery and key structure-activity relationship (SAR) of a series of 2-aminobenzimidazoles as potent Aurora kinase inhibitors. 2-Aminobenzimidazole serves as a bioisostere of the biaryl urea residue of SNS-314 (1c), which is a potent Aurora kinase inhibitor and entered clinical testing in patients with solid tumors. Compared to SNS-314, this series of compounds offers better aqueous solubility while retaining comparable in vitro potency in biochemical and cell-based assays; in particular, 6m has also demonstrated a comparable mouse iv PK profile to SNS-314.

Pharmacists' perceptions of professionalism on social networking sites.

PubMed

Benetoli, Arcelio; Chen, Timothy F; Schaefer, Marion; Chaar, Betty; Aslani, Parisa

Social networking sites (SNS) are a new venue for communication, and health care professionals, like the general population, are using them extensively. However, their behavior on SNS may influence public perceptions about their professionalism. This study explored how pharmacists separate professional and personal information and activities on SNS, their perceptions of professional behavior on SNS, and opinions on guidelines in this area. In-depth, semi-structured interviews were conducted with international practising pharmacists (n = 31) recruited from a range of countries (n = 9). Initially, pharmacists known to the research team were invited, and thereafter, participants were recruited using a snowballing technique. The interviews lasted from 30 to 120 min. All interviews were recorded, transcribed verbatim, and thematically analyzed. A majority of participants mixed professional and personal information and activities on SNS, and about one third adopted a separation strategy where professional information and activities were clearly separated from personal ones (e.g. two different SNS accounts, or one particular SNS for professional use and another platform for personal purposes). Most participants expressed concern over how pharmacists present themselves and behave in SNS when they reported (un)professional behaviors of peers they had observed. Examples of perceived unprofessional behaviors included revealing details of personal life and activities; open complaints about the pharmacy sector, co-workers, physicians, and patients; inappropriate description of pharmacists' roles and activities; and breaches of patient confidentiality. Positive professional behaviors, such as expression of compassion for patients, examples of effective patient management, promotion of pharmacists' role, and correction of misleading health information being spread online were also observed. There was no consensus on having professional social media guidelines. Some preferred SNS to be unregulated while most believed certain guidance was needed to maintain high professional standards in the online environment. A definitive strategy to separate professional and personal information and activities on SNS was not adopted by most pharmacists. E-professionalism issues could negatively impact on the standing of individual practitioners and the profession. Most agreed that education about SNS use would be beneficial; however, support for guidelines or regulations for pharmacists' use of SNS was not unanimous. Copyright © 2016 Elsevier Inc. All rights reserved.

Face-to-Face or Not-to-Face: A Technology Preference for Communication

PubMed Central

Darmawan, Bobby; Mohamed Ariffin, Mohd Yahya

2014-01-01

Abstract This study employed the Model of Technology Preference (MTP) to explain the relationship of the variables as the antecedents of behavioral intention to adopt a social networking site (SNS) for communication. Self-administered questionnaires were distributed to SNS account users using paper-based and web-based surveys that led to 514 valid responses. The data were analyzed using structural equation modeling (SEM). The results show that two out of three attributes of the attribute-based preference (ATRP) affect attitude-based preference (ATTP). The data support the hypotheses that perceived enjoyment and social presence are predictors of ATTP. In this study, the findings further indicated that ATTP has no relationship with the behavioral intention of using SNS, but it has a relationship with the attitude of using SNS. SNS development should provide features that ensure enjoyment and social presence for users to communicate instead of using the traditional face-to-face method of communication. PMID:25405782

Identity Confusion and Materialism Mediate the Relationship Between Excessive Social Network Site Usage and Online Compulsive Buying.

PubMed

Sharif, Saeed Pahlevan; Khanekharab, Jasmine

2017-08-01

This study investigates the mediating role of identity confusion and materialism in the relationship between social networking site (SNS) excessive usage and online compulsive buying among young adults. A total of 501 SNS users aged 17 to 23 years (M = 19.68, SD = 1.65) completed an online survey questionnaire. A serial multiple mediator model was developed and hypotheses were tested using structural equation modeling. The results showed that excessive young adult SNS users had a higher tendency toward compulsive buying online. This was partly because they experienced higher identity confusion and developed higher levels of materialism. Targeted psychological interventions seeking to gradually increase identity clarity to buffer the detrimental effects of SNS usage and identity confusion in young adults are suggested.

Social Networking Site Use While Driving: ADHD and the Mediating Roles of Stress, Self-Esteem and Craving

PubMed Central

Turel, Ofir; Bechara, Antoine

2016-01-01

Background: Adults who present ADHD symptoms have an increased risk for vehicle accidents. One conceivable overlooked account for this association is the possibility that people with ADHD symptoms use rewarding technologies such as social networking sites (SNS) while driving, more than others. The objective of this study was to understand if and how ADHD symptoms can promote SNS use while driving and specifically to conceptualize and examine mechanisms which may underlie this association. To do so, ADHD is viewed in this study as an underlying syndrome that promotes SNS use while driving in a manner similar to how addictive syndromes promote compulsive seeking of drug rewards. Methods: Time-lagged survey data regarding ADHD, stress, self-esteem, SNS craving experience, SNS use while driving, and control variables were collected from a sample of 457 participants who use a popular SNS (Facebook) and drive, after face-validity examination with a panel of five users and pretest with a sample of 47. These data were subjected to structural equation modeling (SEM) analyses using the frequency of ADHD symptoms measured with ASRS v1.1 Part A as a continuous variable, as well as multivariate analysis of variance using ADHD classification based on ASRS v1.1 scoring guidelines. Results: ADHD symptoms promoted increased stress and reduced self-esteem, which in turn, together with ADHD symptoms, increased one's cravings to use the SNS. These cravings ultimately translated into increased SNS use while driving. Using the ASRS v1.1 classification, people having symptoms highly consistent with ADHD presented elevated levels of stress, cravings to use the SNS, and SNS use while driving, as well as decreased levels of self-esteem. Cravings to use the SNS among men were more potent than among women. Conclusion: SNS use while driving may be more prevalent than previously assumed and may be indirectly associated with ADHD symptoms. It is a new form of impulsive and risky behavior which is more common among people with symptoms compatible with ADHD than among others. Consistent with addiction and decision making models, SNS use while driving can be viewed as a form of a compensatory reward seeking behavior. As such, prevention and reduction interventions that target the mediating perceptions and states should be devised. PMID:27065923

Social Networking Site Use While Driving: ADHD and the Mediating Roles of Stress, Self-Esteem and Craving.

PubMed

Turel, Ofir; Bechara, Antoine

2016-01-01

Adults who present ADHD symptoms have an increased risk for vehicle accidents. One conceivable overlooked account for this association is the possibility that people with ADHD symptoms use rewarding technologies such as social networking sites (SNS) while driving, more than others. The objective of this study was to understand if and how ADHD symptoms can promote SNS use while driving and specifically to conceptualize and examine mechanisms which may underlie this association. To do so, ADHD is viewed in this study as an underlying syndrome that promotes SNS use while driving in a manner similar to how addictive syndromes promote compulsive seeking of drug rewards. Time-lagged survey data regarding ADHD, stress, self-esteem, SNS craving experience, SNS use while driving, and control variables were collected from a sample of 457 participants who use a popular SNS (Facebook) and drive, after face-validity examination with a panel of five users and pretest with a sample of 47. These data were subjected to structural equation modeling (SEM) analyses using the frequency of ADHD symptoms measured with ASRS v1.1 Part A as a continuous variable, as well as multivariate analysis of variance using ADHD classification based on ASRS v1.1 scoring guidelines. ADHD symptoms promoted increased stress and reduced self-esteem, which in turn, together with ADHD symptoms, increased one's cravings to use the SNS. These cravings ultimately translated into increased SNS use while driving. Using the ASRS v1.1 classification, people having symptoms highly consistent with ADHD presented elevated levels of stress, cravings to use the SNS, and SNS use while driving, as well as decreased levels of self-esteem. Cravings to use the SNS among men were more potent than among women. SNS use while driving may be more prevalent than previously assumed and may be indirectly associated with ADHD symptoms. It is a new form of impulsive and risky behavior which is more common among people with symptoms compatible with ADHD than among others. Consistent with addiction and decision making models, SNS use while driving can be viewed as a form of a compensatory reward seeking behavior. As such, prevention and reduction interventions that target the mediating perceptions and states should be devised.

Interests diffusion in social networks

NASA Astrophysics Data System (ADS)

D'Agostino, Gregorio; D'Antonio, Fulvio; De Nicola, Antonio; Tucci, Salvatore

2015-10-01

We provide a model for diffusion of interests in Social Networks (SNs). We demonstrate that the topology of the SN plays a crucial role in the dynamics of the individual interests. Understanding cultural phenomena on SNs and exploiting the implicit knowledge about their members is attracting the interest of different research communities both from the academic and the business side. The community of complexity science is devoting significant efforts to define laws, models, and theories, which, based on acquired knowledge, are able to predict future observations (e.g. success of a product). In the mean time, the semantic web community aims at engineering a new generation of advanced services by defining constructs, models and methods, adding a semantic layer to SNs. In this context, a leapfrog is expected to come from a hybrid approach merging the disciplines above. Along this line, this work focuses on the propagation of individual interests in social networks. The proposed framework consists of the following main components: a method to gather information about the members of the social networks; methods to perform some semantic analysis of the Domain of Interest; a procedure to infer members' interests; and an interests evolution theory to predict how the interests propagate in the network. As a result, one achieves an analytic tool to measure individual features, such as members' susceptibilities and authorities. Although the approach applies to any type of social network, here it is has been tested against the computer science research community. The DBLP (Digital Bibliography and Library Project) database has been elected as test-case since it provides the most comprehensive list of scientific production in this field.

The social network-network: size is predicted by brain structure and function in the amygdala and paralimbic regions

PubMed Central

Von Der Heide, Rebecca; Vyas, Govinda

2014-01-01

The social brain hypothesis proposes that the large size of the primate neocortex evolved to support complex and demanding social interactions. Accordingly, recent studies have reported correlations between the size of an individual’s social network and the density of gray matter (GM) in regions of the brain implicated in social cognition. However, the reported relationships between GM density and social group size are somewhat inconsistent with studies reporting correlations in different brain regions. One factor that might account for these discrepancies is the use of different measures of social network size (SNS). This study used several measures of SNS to assess the relationships SNS and GM density. The second goal of this study was to test the relationship between social network measures and functional brain activity. Participants performed a social closeness task using photos of their friends and unknown people. Across the VBM and functional magnetic resonance imaging analyses, individual differences in SNS were consistently related to structural and functional differences in three regions: the left amygdala, right amygdala and the right entorhinal/ventral anterior temporal cortex. PMID:24493846

Facile and fast synthesis of SnS2 nanoparticles by pulsed laser ablation in liquid

NASA Astrophysics Data System (ADS)

Johny, J.; Sepulveda-Guzman, S.; Krishnan, B.; Avellaneda, D.; Shaji, S.

2018-03-01

Nanoparticles (NPs) of tin disulfide (SnS2) were synthesized using pulsed laser ablation in liquid (PLAL) technique. Effects of different liquid media and ablation wavelengths on the morphology and optical properties of the nanoparticles were studied. Nd: YAG laser wavelengths of 532 nm and 1064 nm (frequency 10 Hz and pulse width 10 ns) were used to irradiate SnS2 target immersed in liquid for the synthesis of SnS2 nanoparticles. Here PLAL was a fast synthesis technique, the ablation was only for 30 s. Transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, UV-vis absorption spectroscopy and photoluminescence spectroscopy were used to characterize the SnS2 NPs. TEM images showed that the liquid medium and laser wavelength influence the morphology of the NPs. SAED patterns and high resolution TEM (HRTEM) images confirmed the crystallinity of the particles. XRD and XPS analyses confirmed that SnS2 NPs were having exact crystalline structure and chemical states as that of the target. Raman analysis also supported the results obtained by XRD and XPS. Optical band gaps of the nanocolloids evaluated from their UV-vis absorption spectra were 2.4-3.05 eV. SnS2 NPs were having luminescence spectra in the blue-green region irrespective of the liquid media and ablation wavelength.

Surface plasmon resonance induced enhancement of photoluminescence and Raman line intensity in SnS quantum dot-Sn nanoparticle hybrid structure.

PubMed

Warrier, Anita R; Gandhimathi, R

2018-04-27

In this article, we report on enhancement in photoluminescence and Raman line intensity of SnS quantum dots embedded in a mesh of Sn nanostructures. SnS nanoparticles synthesized by homogenous precipitation method show strong quantum confinement with a band gap of ∼2.7 eV (blue shift of ∼1 eV compared to bulk SnS particles). The optical band gap of SnS quantum dots is controlled by varying the pH (∼0 to 2.25), ageing time (24 to 144 h) and molarity (0 to 2 M) of the precursors. These SnS nanoparticles are embedded in a mesh of Sn nanostructures which are synthesized from tin chloride by using sodium borohydride as reducing agent. The Sn nanostructures have a morphology dependent, tunable surface plasmon resonance (SPR), ranging from UV (∼295 nm) to visible region (∼400 nm) of the electromagnetic spectrum. In the SnS-Sn nanohybrids, the excitons are strongly coupled with plasmons leading to a shift in the excitonic binding energy (∼400 meV). The pure SnS quantum dots have a very weak photoluminescence peak at ∼560 nm and Raman shift of low intensity at 853.08 cm -1 , 1078.17 cm -1 , 1255.60 cm -1 , 1466.91 cm -1 . The coupling of SnS nanoparticles with Sn nanoparticles results in strong exciton-plasmon interactions leading to enhanced photoluminescence and Raman line intensity. The nanohybrids formed using Sn nanosheets whose SPR matches with absorption onset of the SnS nanoparticles shows an enhancement of ∼10 4 times higher than pure SnS nanoparticles. Thus, Sn nanosheet with surface plasmon resonance in visible region (400 nm) like Au and Ag is a promising material for surface enhanced Raman spectroscopy, plasmon assisted fluorescence imaging and for enhancing the emission intensity of semiconductors with weak emission intensity.

Surface plasmon resonance induced enhancement of photoluminescence and Raman line intensity in SnS quantum dot-Sn nanoparticle hybrid structure

NASA Astrophysics Data System (ADS)

Warrier, Anita R.; Gandhimathi, R.

2018-07-01

In this article, we report on enhancement in photoluminescence and Raman line intensity of SnS quantum dots embedded in a mesh of Sn nanostructures. SnS nanoparticles synthesized by homogenous precipitation method show strong quantum confinement with a band gap of ∼2.7 eV (blue shift of ∼1 eV compared to bulk SnS particles). The optical band gap of SnS quantum dots is controlled by varying the pH (∼0 to 2.25), ageing time (24 to 144 h) and molarity (0 to 2 M) of the precursors. These SnS nanoparticles are embedded in a mesh of Sn nanostructures which are synthesized from tin chloride by using sodium borohydride as reducing agent. The Sn nanostructures have a morphology dependent, tunable surface plasmon resonance (SPR), ranging from UV (∼295 nm) to visible region (∼400 nm) of the electromagnetic spectrum. In the SnS-Sn nanohybrids, the excitons are strongly coupled with plasmons leading to a shift in the excitonic binding energy (∼400 meV). The pure SnS quantum dots have a very weak photoluminescence peak at ∼560 nm and Raman shift of low intensity at 853.08 cm‑1, 1078.17 cm‑1, 1255.60 cm‑1, 1466.91 cm‑1. The coupling of SnS nanoparticles with Sn nanoparticles results in strong exciton-plasmon interactions leading to enhanced photoluminescence and Raman line intensity. The nanohybrids formed using Sn nanosheets whose SPR matches with absorption onset of the SnS nanoparticles shows an enhancement of ∼104 times higher than pure SnS nanoparticles. Thus, Sn nanosheet with surface plasmon resonance in visible region (400 nm) like Au and Ag is a promising material for surface enhanced Raman spectroscopy, plasmon assisted fluorescence imaging and for enhancing the emission intensity of semiconductors with weak emission intensity.

Electronic and magnetic properties of SnS2 monolayer doped with non-magnetic elements

NASA Astrophysics Data System (ADS)

Xiao, Wen-Zhi; Xiao, Gang; Rong, Qing-Yan; Wang, Ling-Ling

2018-05-01

We performed a systematic study of the electronic structures and magnetic properties of SnS2 monolayer doped with non-magnetic elements in groups IA, IIA and IIIA based on the first-principles methods. The doped systems exhibit half-metallic and metallic natures depending on the doping elements. The formation of magnetic moment is attributable to the cooperative effect of the Hund's rule coupling and hole concentration. The spin polarization can be stabilized and enhanced through confining the delocalized impurity states by biaxial tensile strain in hole-doped SnS2 monolayer. Both the double-exchange and p-p exchange mechanisms are simultaneously responsible for the ferromagnetic ground state in those hole-doped materials. Our results demonstrate that spin polarization can be induced and controlled in SnS2 monolayers by non-magnetic doping and tensile strain.

van der Waals epitaxy of SnS film on single crystal graphene buffer layer on amorphous SiO2/Si

NASA Astrophysics Data System (ADS)

Xiang, Yu; Yang, Yunbo; Guo, Fawen; Sun, Xin; Lu, Zonghuan; Mohanty, Dibyajyoti; Bhat, Ishwara; Washington, Morris; Lu, Toh-Ming; Wang, Gwo-Ching

2018-03-01

Conventional hetero-epitaxial films are typically grown on lattice and symmetry matched single crystal substrates. We demonstrated the epitaxial growth of orthorhombic SnS film (∼500 nm thick) on single crystal, monolayer graphene that was transferred on the amorphous SiO2/Si substrate. Using X-ray pole figure analysis we examined the structure, quality and epitaxy relationship of the SnS film grown on the single crystal graphene and compared it with the SnS film grown on commercial polycrystalline graphene. We showed that the SnS films grown on both single crystal and polycrystalline graphene have two sets of orientation domains. However, the crystallinity and grain size of the SnS film improve when grown on the single crystal graphene. Reflection high-energy electron diffraction measurements show that the near surface texture has more phases as compared with that of the entire film. The surface texture of a film will influence the growth and quality of film grown on top of it as well as the interface formed. Our result offers an alternative approach to grow a hetero-epitaxial film on an amorphous substrate through a single crystal graphene buffer layer. This strategy of growing high quality epitaxial thin film has potential applications in optoelectronics.

College Students' Drinking and Posting About Alcohol: Forwarding a Model of Motivations, Behaviors, and Consequences.

PubMed

Thompson, Charee M; Romo, Lynsey K

2016-06-01

College drinking continues to remain a public health problem that has been exacerbated by alcohol-related posts on social networking sites (SNSs). Although existing research has linked alcohol consumption, alcohol posts, and adverse consequences to one another, comprehensive explanations for these associations have been largely unexplored. Thus, we reasoned that students' personal motivations (i.e., espousing an alcohol identity, needing entertainment, and adhering to social norms) influence their behaviors (i.e., alcohol consumption and alcohol-related posting on SNSs), which can lead to alcohol problems. Using structural equation modeling, we analyzed data from 364 undergraduate students and found general support for our model. In particular, espousing an alcohol identity predicted alcohol consumption and alcohol-related SNS posting, needing entertainment predicted alcohol consumption but not alcohol-related SNS posting, and adhering to social norms predicted alcohol-related SNS posting but not alcohol consumption. In turn, alcohol consumption and alcohol-related SNS posting predicted alcohol problems. It is surprising that alcohol-related SNS posting was a stronger predictor of alcohol problems than alcohol consumption. We discuss the findings within their applied applications for college student health.

Development of a researcher codebook for use in evaluating social networking site profiles.

PubMed

Moreno, Megan A; Egan, Katie G; Brockman, Libby

2011-07-01

Social networking sites (SNSs) are immensely popular and allow for the display of personal information, including references to health behaviors. Evaluating displayed content on an SNS for research purposes requires a systematic approach and a precise data collection instrument. The purpose of this article is to describe one approach to the development of a research codebook so that others may develop and test their own codebooks for use in SNS research. Our SNS research codebook began on the basis of health behavior theory and clinical criteria. Key elements in the codebook developmental process included an iterative team approach and an emphasis on confidentiality. Codebook successes include consistently high inter-rater reliability. Challenges include time investment in coder training and SNS server changes. We hope that this article will provide detailed information about one systematic approach to codebook development so that other researchers may use this structure to develop and test their own codebooks for use in SNS research. Copyright © 2011 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Higher Order Mode Analysis of the SNS Superconducting Linac

DOE Office of Scientific and Technical Information (OSTI.GOV)

M. Doleans; D. Jeon; S. Kim

2001-06-01

Higher order modes (HOM's) of monopoles, dipoles, quadrupoles and sextupoles in {beta} = 0.61 and {beta} = 0.81 6-cell superconducting (SC) cavities for the Spallation Neutron Source (SNS) project, have been found up to about 3 GHz and their properties such as R/Q, trapping possibility, etc have been figured out in concerning with the manufacturing imperfection. Main issues of HOM's are beam instabilities (published separately) and HOM induced power especially from TM monopoles. The time structure of SNS beam has three different time scales of pulses, which are micro-pulse, midi-pulse and macropulse. Each time structure will generate resonances. When amore » mode is near these resonance frequencies, the induced voltage could be large and accordingly the resulting HOM power, too. In order to understand the effects from such a complex beam time structure on the mode excitation and resulting HOM power, analytic expressions are developed. With these analytic expressions, the induced HOM voltage and HOM power were calculated by assuming external Q for each HOM.« less

High-Resolution Tracking Asymmetric Lithium Insertion and Extraction and Local Structure Ordering in SnS2.

PubMed

Gao, Peng; Wang, Liping; Zhang, Yu-Yang; Huang, Yuan; Liao, Lei; Sutter, Peter; Liu, Kaihui; Yu, Dapeng; Wang, En-Ge

2016-09-14

In the rechargeable lithium ion batteries, the rate capability and energy efficiency are largely governed by the lithium ion transport dynamics and phase transition pathways in electrodes. Real-time and atomic-scale tracking of fully reversible lithium insertion and extraction processes in electrodes, which would ultimately lead to mechanistic understanding of how the electrodes function and why they fail, is highly desirable but very challenging. Here, we track lithium insertion and extraction in the van der Waals interactions dominated SnS2 by in situ high-resolution TEM method. We find that the lithium insertion occurs via a fast two-phase reaction to form expanded and defective LiSnS2, while the lithium extraction initially involves heterogeneous nucleation of intermediate superstructure Li0.5SnS2 domains with a 1-4 nm size. Density functional theory calculations indicate that the Li0.5SnS2 is kinetically favored and structurally stable. The asymmetric reaction pathways may supply enlightening insights into the mechanistic understanding of the underlying electrochemistry in the layered electrode materials and also suggest possible alternatives to the accepted explanation of the origins of voltage hysteresis in the intercalation electrode materials.

Characterization of hydrothermally synthesized SnS nanoparticles for solar cell application

NASA Astrophysics Data System (ADS)

Rajwar, Birendra Kumar; Sharma, Shailendra Kumar

2018-05-01

In the present study, SnS nanoparticles were synthesized by simple hydrothermal method using stannous chloride and thiourea as tin (Sn) and sulfur (S) precursor respectively. Synthesized nanoparticles were characterized by X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy and UV-Vis Spectroscopy techniques. XRD pattern reveals that as-prepared nanoparticles exhibit orthorhombic structure. Average particles size was calculated using Scherrer's formula and found to be 23 nm. FESEM image shows that the as-prepared nanoparticles are in plate like structure. Direct optical band gap (Eg) of as-synthesized nanoparticles was calculated through UV-Vis Spectroscopy measurement and found to be 1.34 eV, which is near to optimum need for photovoltaic solar energy conversion (1.5 eV). Thus this SnS, narrowband gap semiconductor material can be applied as an alternative absorber material for solar cell application.

Impact of additional sulphur on structure, morphology and optical properties of SnS thin films by thermal evaporation

NASA Astrophysics Data System (ADS)

Banotra, Arun; Padha, Naresh; Kumar, Shiv; Kapoor, Ashok K.

2018-05-01

Thin films of SnS have been obtained from Sn and S powders which were mixed up using ball mill technique with and without evaporating additional sulphur prior to annealing at 523K. The obtained samples were taken for structural, optical, chemical and morphological studies. The X-ray diffraction reveals the formation of SnS phase on annealing in vacuum having S/Sn ratio of 0.67 obtained from EDAX. This deficit in `S' is removed by supplementing additional `S' of 200nm prior to annealing which results in the S/Sn ratio of 1.01. The optical transmission recorded from spectrophotometer used to study different optical parameters. Morphological results corroborate well with the XRD, EDAX and optical study. The obtained stoichiometric films were also tested for Ag/p-SnS Schottky diodes on In coated glass substrates using current voltage measurements.

Self-Concealment, Social Network Sites Usage, Social Appearance Anxiety, Loneliness of High School Students: A Model Testing

ERIC Educational Resources Information Center

Dogan, Ugur; Çolak, Tugba Seda

2016-01-01

This study was tested a model for explain to social networks sites (SNS) usage with structural equation modeling (SEM). Using SEM on a sample of 475 high school students (35% male, 65% female) students, model was investigated the relationship between self-concealment, social appearance anxiety, loneliness on SNS such as Twitter and Facebook usage.…

How do general practice residents use social networking sites in asynchronous distance learning?

PubMed

Maisonneuve, Hubert; Chambe, Juliette; Lorenzo, Mathieu; Pelaccia, Thierry

2015-09-21

Blended learning environments - involving both face-to-face and remote interactions - make it easier to adapt learning programs to constraints such as residents' location and low teacher-student ratio. Social networking sites (SNS) such as Facebook®, while not originally intended to be used as learning environments, may be adapted for the distance-learning part of training programs. The purpose of our study was to explore the use of SNS for asynchronous distance learning in a blended learning environment as well as its influence on learners' face-to-face interactions. We conducted a qualitative study and carried out semi-structured interviews. We performed purposeful sampling for maximal variation to include eight general practice residents in 2(nd) and 3(rd) year training. A thematic analysis was performed. The social integration of SNS facilitates the engagement of users in their learning tasks. This may also stimulate students' interactions and group cohesion when members meet up in person. Most of the general practice residents who work in the blended learning environment we studied had a positive appraisal on their use of SNS. In particular, we report a positive impact on their engagement in learning and their participation in discussions during face-to-face instruction. Further studies are needed in order to evaluate the effectiveness of SNS in blended learning environments and the appropriation of SNS by teachers.

Thermoelectric properties of SnSe1-xSx(0

NASA Astrophysics Data System (ADS)

Nguyen, Thi Minh Hai; Duong, Anh Tuan; Duvjir, Ganbat; Trinh, Thi Ly; Nguyen, Van Quang; Kim, Jungdae; Cho, Sunglae

Tin selenide (SnSe), a p-type semiconductor, has attracted many attention due to its excellent thermoelectric efficiency, i.e., ZT = 2.6 along the b-axis of its high temperature phase. This issue has renewed interests in thermoelectric properties of the materials which adopted the same layered structure as SnSe, such as SnS, GeS, and GeSe. Among these compounds, tin (II) sulfide (SnS) is exceptionally attractive because of its natural abundance and low toxicity. However, the experimental results show that SnS has possessed a small value of the figure of merit. To optimize the thermoelectric performance of SnS, making solid solution is a potential way. That is our motivation for the investigation of SnSe1-xSx single crystals' thermoelectric properties. In this study, SnSe1-xSx (0

New insights into the structure, chemistry, and properties of Cu 4SnS 4

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choudhury, Amitava; Mohapatra, Sudip; Yaghoobnejad Asl, Hooman

The ambient temperature structure of Cu 4SnS 4 has been revisited and the recently reported low temperature structure has been confirmed from single-crystal X-ray diffraction data. A structural phase transition from a large monoclinic unit cell at low temperature to a smaller orthorhombic unit cell at high temperature has been observed. The room temperature phase exhibited disorder in the two copper sites, which is a different finding from earlier reports. The low temperature monoclinic form crystallizes in P2 1/c space group, which is isostructural with Cu 4GeS 4. The phase transition has also been studied with variable temperature powder X-raymore » diffraction and 119Sn Mössbauer spectroscopy. The Seebeck coefficients and electrical resistivity of polycrystalline Cu 4SnS 4 are reported from 16 to 400 K on hot pressed pellets. Thermal conductivity measurements at high temperatures, 350 – 750 K exhibited very low thermal conductivities in the range 0.28 – 0.35 W K –1 m –1. In all the transport measurements the phase transition has been observed at around 232 K. Resistivity decreases, while Seebeck coefficient increases after the phase transition during warming up from low to high temperatures. This change in resistivity has been correlated with the results of first-principles electronic band structure calculations using highly-accurate screened-exchange local density approximation. It was found that both the low hole effective mass of 0.63 me for the Γ→Y crystallographic direction and small band gap, 0.49 eV, are likely to contribute to the observed higher conductivity of the orthorhombic phase. Cu 4SnS 4 is also electrochemically active and shows reversible reaction with lithium between 1.7 and 3.5 volts.« less

New insights into the structure, chemistry, and properties of Cu 4SnS 4

DOE PAGES

Choudhury, Amitava; Mohapatra, Sudip; Yaghoobnejad Asl, Hooman; ...

2017-05-25

The ambient temperature structure of Cu 4SnS 4 has been revisited and the recently reported low temperature structure has been confirmed from single-crystal X-ray diffraction data. A structural phase transition from a large monoclinic unit cell at low temperature to a smaller orthorhombic unit cell at high temperature has been observed. The room temperature phase exhibited disorder in the two copper sites, which is a different finding from earlier reports. The low temperature monoclinic form crystallizes in P2 1/c space group, which is isostructural with Cu 4GeS 4. The phase transition has also been studied with variable temperature powder X-raymore » diffraction and 119Sn Mössbauer spectroscopy. The Seebeck coefficients and electrical resistivity of polycrystalline Cu 4SnS 4 are reported from 16 to 400 K on hot pressed pellets. Thermal conductivity measurements at high temperatures, 350 – 750 K exhibited very low thermal conductivities in the range 0.28 – 0.35 W K –1 m –1. In all the transport measurements the phase transition has been observed at around 232 K. Resistivity decreases, while Seebeck coefficient increases after the phase transition during warming up from low to high temperatures. This change in resistivity has been correlated with the results of first-principles electronic band structure calculations using highly-accurate screened-exchange local density approximation. It was found that both the low hole effective mass of 0.63 me for the Γ→Y crystallographic direction and small band gap, 0.49 eV, are likely to contribute to the observed higher conductivity of the orthorhombic phase. Cu 4SnS 4 is also electrochemically active and shows reversible reaction with lithium between 1.7 and 3.5 volts.« less

System and method for embedding emotion in logic systems

NASA Technical Reports Server (NTRS)

Curtis, Steven A. (Inventor)

2012-01-01

A system, method, and computer readable-media for creating a stable synthetic neural system. The method includes training an intellectual choice-driven synthetic neural system (SNS), training an emotional rule-driven SNS by generating emotions from rules, incorporating the rule-driven SNS into the choice-driven SNS through an evolvable interface, and balancing the emotional SNS and the intellectual SNS to achieve stability in a nontrivial autonomous environment with a Stability Algorithm for Neural Entities (SANE). Generating emotions from rules can include coding the rules into the rule-driven SNS in a self-consistent way. Training the emotional rule-driven SNS can occur during a training stage in parallel with training the choice-driven SNS. The training stage can include a self assessment loop which measures performance characteristics of the rule-driven SNS against core genetic code. The method uses a stability threshold to measure stability of the incorporated rule-driven SNS and choice-driven SNS using SANE.

Spallation radiation effects in materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mansur, L.K.; Farrell, K.; Wechsler, M.S.

1996-06-01

Spallation refers to the process whereby particles (chiefly neutrons) are ejected from nuclei upon bombardment by high-energy protons. Spallation neutron sources (SNS`s) use these neutrons for neutron scattering and diffraction research, and SNS`s are proposed as the basis for systems for tritium production and transmutation of nuclear waste. Materials in SNS`s are exposed to the incident proton beam (energies typically about 1000 MeV) and to the spallation neutrons (spectrum of energies extending up to about 1000 MeV). By contrast the fission neutrons in nuclear reactors have an average energy of only about 2 MeV, and the neutrons in fusion reactorsmore » would have energies below about 14 MeV. Furthermore, the protons and neutrons in SNS`s for scattering and diffraction research are pulsed at frequencies of about 10 to 60 Hz, from which significant changes in the kinetics of point and extended defects may be expected. In addition, much higher transmutation rates occur in SNS-irradiated materials, On the whole, then, significant differences in microstructural development and macroscopic properties may result upon exposure in SNS systems, as compared with fission and fusion irradiations. In a more general sense, subjecting materials to new radiation environments has almost routinely led to new discoveries. To the extent that data are avaiable, however, the spallation environment appears to increase the degree of damage without introducing totally new effects. The first part of this presentation is an overview of radiation effects in materials, outlining essential concepts and property changes and their physical bases. This background is followed by a description of SNS irradiation environments and the effects on materials of exposure to these environments. A special discussion is given of the selection of target (e.g., liquid mercury), container (e.g., austenitic stainless steel or ferritic/martensitic steel), and structural materials in SNS systems.« less

n-type conversion of SnS by isovalent ion substitution: Geometrical doping as a new doping route

PubMed Central

Ran, Fan-Yong; Xiao, Zewen; Toda, Yoshitake; Hiramatsu, Hidenori; Hosono, Hideo; Kamiya, Toshio

2015-01-01

Tin monosulfide (SnS) is a naturally p-type semiconductor with a layered crystal structure, but no reliable n-type SnS has been obtained by conventional aliovalent ion substitution. In this work, carrier polarity conversion to n-type was achieved by isovalent ion substitution for polycrystalline SnS thin films on glass substrates. Substituting Pb2+ for Sn2+ converted the majority carrier from hole to electron, and the free electron density ranged from 1012 to 1015 cm−3 with the largest electron mobility of 7.0 cm2/(Vs). The n-type conduction was confirmed further by the position of the Fermi level (EF) based on photoemission spectroscopy and electrical characteristics of pn heterojunctions. Density functional theory calculations reveal that the Pb substitution invokes a geometrical size effect that enlarges the interlayer distance and subsequently reduces the formation energies of Sn and Pb interstitials, which results in the electron doping. PMID:26020855

Temperature controlled properties of sub-micron thin SnS films

NASA Astrophysics Data System (ADS)

Nwankwo, Stephen N.; Campbell, Stephen; Reddy, Ramakrishna K. T.; Beattie, Neil S.; Barrioz, Vincent; Zoppi, Guillaume

2018-06-01

Tin sulphide (SnS) thin films deposited by thermal evaporation on glass substrates are studied for different substrate temperatures. The increase in substrate temperature results in the increase of the crystallite size and change in orientation of the films. The crystal structure of the films is that of SnS only and for temperatures ≤300 °C the films are of random orientation, whereas for higher temperatures the films become (040) oriented. The variation of Sn/S composition was accompanied by a reduction in optical energy bandgap from 1.47 to 1.31 eV as the substrate temperature increases. The Urbach energy was found stable at 0.169 ± 0.002 eV for temperature up to 350 °C. Photoluminescence emission was observed only for films exhibiting stoichiometric properties and shows that a precise control of the film composition is critical to fabricate devices while an increase in grain size will be essential to achieve high efficiency.

Modularized Parallel Neutron Instrument Simulation on the TeraGrid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Meili; Cobb, John W; Hagen, Mark E

2007-01-01

In order to build a bridge between the TeraGrid (TG), a national scale cyberinfrastructure resource, and neutron science, the Neutron Science TeraGrid Gateway (NSTG) is focused on introducing productive HPC usage to the neutron science community, primarily the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL). Monte Carlo simulations are used as a powerful tool for instrument design and optimization at SNS. One of the successful efforts of a collaboration team composed of NSTG HPC experts and SNS instrument scientists is the development of a software facility named PSoNI, Parallelizing Simulations of Neutron Instruments. Parallelizing the traditional serialmore » instrument simulation on TeraGrid resources, PSoNI quickly computes full instrument simulation at sufficient statistical levels in instrument de-sign. Upon SNS successful commissioning, to the end of 2007, three out of five commissioned instruments in SNS target station will be available for initial users. Advanced instrument study, proposal feasibility evalua-tion, and experiment planning are on the immediate schedule of SNS, which pose further requirements such as flexibility and high runtime efficiency on fast instrument simulation. PSoNI has been redesigned to meet the new challenges and a preliminary version is developed on TeraGrid. This paper explores the motivation and goals of the new design, and the improved software structure. Further, it describes the realized new fea-tures seen from MPI parallelized McStas running high resolution design simulations of the SEQUOIA and BSS instruments at SNS. A discussion regarding future work, which is targeted to do fast simulation for automated experiment adjustment and comparing models to data in analysis, is also presented.« less

Perceptions of Pediatric Residents Regarding Counseling About Use of Social Networking Sites.

PubMed

Banker, Sumeet L; Fenick, Ada M; Qin, Li; Talwalkar, Jaideep S

2018-04-01

Increasing use of social networking sites (SNS) among youth prompted professional organizations to urge pediatricians to promote healthy media use. Electronic questionnaires were distributed to 76 pediatric residents at one academic center measuring attitudes, practices, and familiarity with SNS. Of 43 respondents (response rate = 57%), most reported personal SNS use (98%) and familiarity with SNS used by youth (72%), and 88% agreed that pediatricians should provide counseling on SNS use. Only 5% felt they had adequate training on SNS use in children, and just 26% felt comfortable advising families. Residents were less likely to discuss SNS use than general media use (19% vs 56%, P = .007). Media counseling was correlated with SNS counseling ( r = .38, P = .01). Pediatric residents recognize the importance of guiding families on SNS use, yet do not routinely provide counseling despite high levels of personal SNS use and familiarity. Focused training is necessary for pediatricians to prioritize practical guidance.

ABCB1 as predominant resistance mechanism in cells with acquired SNS-032 resistance

PubMed Central

Rothweiler, Florian; Voges, Yvonne; Balónová, Barbora; Blight, Barry A.; Cinatl, Jindrich

2016-01-01

The CDK inhibitor SNS-032 had previously exerted promising anti-neuroblastoma activity via CDK7 and 9 inhibition. ABCB1 expression was identified as major determinant of SNS-032 resistance. Here, we investigated the role of ABCB1 in acquired SNS-032 resistance. In contrast to ABCB1-expressing UKF-NB-3 sub-lines resistant to other ABCB1 substrates, SNS-032-adapted UKF-NB-3 (UKF-NB-3rSNS- 032300nM) cells remained sensitive to the non-ABCB1 substrate cisplatin and were completely re-sensitized to cytotoxic ABCB1 substrates by ABCB1 inhibition. Moreover, UKF-NB-3rSNS-032300nM cells remained similarly sensitive to CDK7 and 9 inhibition as UKF-NB-3 cells. In contrast, SHEPrSNS-0322000nM, the SNS-032-resistant sub-line of the neuroblastoma cell line SHEP, displayed low level SNS-032 resistance also when ABCB1 was inhibited. This discrepancy may be explained by the higher SNS-032 concentrations that were used to establish SHEPrSNS-0322000nM cells, since SHEP cells intrinsically express ABCB1 and are less sensitive to SNS-032 (IC50 912 nM) than UKF-NB-3 cells (IC50 153 nM). In conclusion, we show that ABCB1 expression represents the primary (sometimes exclusive) resistance mechanism in neuroblastoma cells with acquired resistance to SNS-032. Thus, ABCB1 inhibitors may increase the SNS-032 efficacy in ABCB1-expressing cells and prolong or avoid resistance formation. PMID:27517323

Enhanced light trapping and high charge transmission capacities of novel structures for efficient photoelectrochemical water splitting.

PubMed

Mu, Jianglong; Miao, Hui; Liu, Enzhou; Feng, Juan; Teng, Feng; Zhang, Dekai; Kou, Yumeng; Jin, Yanping; Fan, Jun; Hu, Xiaoyun

2018-06-13

Excellent PEC efficiency, good reusability and the super stability of trap-like SnS2/TiO2 nanotube arrays (NTs)-based photoanodes are reported. Specifically, the SnS2/TiO2-180 °C (ST-180) photoanode exhibited the highest photocurrent density (1.05 mA cm-2) and an optimal η (0.73%) at 0.5 V (vs. SCE) under simulated light irradiation (AM 1.5G), which are 4.6 and 3.8 times higher than those of pure TiO2 NTs (0.23 mA cm-2 and 0.19%). The IPCE values of ST-180 can reach 21.5% (365 nm) and 13.8% (420 nm), which are much higher than those of pure TiO2 NTs (10.6% at 365 nm and 0.8% at 420 nm). The APCE values of the pure TiO2 NTs photoelectrode are 12.8% (365 nm) and 1.1% (420 nm), while the ST-180 values are 22.3% and 14.2%, respectively. Furthermore, the generation rates of H2 and O2 for the ST-180 photoanode are 47.2 and 23.1 μmol cm-2 h-1 at 0.5 V under AM 1.5G, corresponding to faradaic efficiencies of around 80.1% and 78.3%, respectively. In short, the high-efficiency PEC water splitting performance of this SnS2/TiO2 photoanode results from the enhanced light harvesting ability of the trap-like SnS2 structure, accelerated carrier transportation properties of TiO2 NTs, and effective carrier separation of the type-II heterojunction structure. This work may offer a combinatorial strategy for the preparation of heterojunction structures with high PEC performance and can be a model structure for similar photoanode materials.

Improved electrical properties of atomic layer deposited tin disulfide at low temperatures using ZrO2 layer

NASA Astrophysics Data System (ADS)

Lee, Juhyun; Lee, Jeongsu; Ham, Giyul; Shin, Seokyoon; Park, Joohyun; Choi, Hyeongsu; Lee, Seungjin; Kim, Juyoung; Sul, Onejae; Lee, Seungbeck; Jeon, Hyeongtag

2017-02-01

We report the effect of zirconium oxide (ZrO2) layers on the electrical characteristics of multilayered tin disulfide (SnS2) formed by atomic layer deposition (ALD) at low temperatures. SnS2 is a two-dimensional (2D) layered material which exhibits a promising electrical characteristics as a channel material for field-effect transistors (FETs) because of its high mobility, good on/off ratio and low temperature processability. In order to apply these 2D materials to large-scale and flexible electronics, it is essential to develop processes that are compatible with current electronic device manufacturing technology which should be conducted at low temperatures. Here, we deposited a crystalline SnS2 at 150 °C using ALD, and we then annealed at 300 °C. X-ray diffraction (XRD) and Raman spectroscopy measurements before and after the annealing showed that SnS2 had a hexagonal (001) peak at 14.9° and A1g mode at 313 cm-1. The annealed SnS2 exhibited clearly a layered structure confirmed by the high resolution transmission electron microscope (HRTEM) images. Back-gate FETs with SnS2 channel sandwiched by top and bottom ZrO2 on p++Si/SiO2 substrate were suggested to improve electrical characteristics. We used a bottom ZrO2 layer to increase adhesion between the channel and the substrate and a top ZrO2 layer to improve contact property, passivate surface, and protect from process-induced damages to the channel. ZTZ (ZrO2/SnS2/ZrO2) FETs showed improved electrical characteristics with an on/off ratio of from 0.39×103 to 6.39×103 and a mobility of from 0.0076 cm2/Vs to 0.06 cm2/Vs.

Addictive use of social networking sites can be explained by the interaction of Internet use expectancies, Internet literacy, and psychopathological symptoms.

PubMed

Wegmann, Elisa; Stodt, Benjamin; Brand, Matthias

2015-09-01

Most people use the Internet in a functional way to achieve certain goals and needs. However, there is an increasing number of people who experience negative consequences like loss of control and distress based on an excessive use of the Internet and its specific online applications. Some approaches postulate similarities with behavioral addictions as well as substance dependencies. They differentiate between a generalized and a specific Internet addiction, such as the pathological use of social networking sites (SIA-SNS). Prior studies particularly identified the use of applications, personal characteristics, and psychopathological symptoms as significant predictors for the development and maintenance of this phenomenon. So far, it remains unclear how psychopathological symptoms like depression and social anxiety interact with individual expectancies of Internet use and capabilities of handling the Internet, summarized as Internet literacy. The current study (N = 334) investigated the interaction of these components in a structural equation model. The results indicate that the effects of depression and social anxiety on SIA-SNS were mediated by Internet use expectancies and self-regulation. Thus, Internet use expectancies seem to be crucial for SIA-SNS, which is in line with prior models. SNS use may be reinforced by experienced gratification and relief from negative feelings. Individual competences in handling the Internet may be preventive for the development of SIA-SNS.

Evidence for a curvilinear relationship between sympathetic nervous system activation and women's physiological sexual arousal.

PubMed

Lorenz, Tierney Ahrold; Harte, Christopher B; Hamilton, Lisa Dawn; Meston, Cindy M

2012-01-01

There is increasing evidence that women's physiological sexual arousal is facilitated by moderate sympathetic nervous system (SNS) activation. Literature also suggests that the level of SNS activation may play a role in the degree to which SNS activity affects sexual arousal. We provide the first empirical examination of a possible curvilinear relationship between SNS activity and women's genital arousal using a direct measure of SNS activation in 52 sexually functional women. The relationship between heart rate variability (HRV), a specific and sensitive marker of SNS activation, and vaginal pulse amplitude (VPA), a measure of genital arousal, was analyzed. Moderate increases in SNS activity were associated with higher genital arousal, while very low or very high SNS activation was associated with lower genital arousal. These findings imply that there is an optimal level of SNS activation for women's physiological sexual arousal. Copyright © 2011 Society for Psychophysiological Research.

Ultrasonic synthesis of In-doped SnS nanoparticles and their physical properties

NASA Astrophysics Data System (ADS)

Jamali-Sheini, Farid; Cheraghizade, Mohsen; Yousefi, Ramin

2018-05-01

Indium (In)-doped Tin (II) Sulfide (SnS) nanoparticles (NPs) were synthesized by an ultra-sonication method and their optical, electrical, dielectric and photocatalytic properties were investigated. XRD patterns of the obtained NPs indicated formation of orthorhombic polycrystalline SnS. Field emission scanning electron microscopy exhibited flower-like NPs with particle sizes below 100 nm for both SnS and In-doped SnS samples. Optical analysis showed a decrease in energy band gap of SnS NPs upon In doping. In addition, electrical results demonstrated p-type nature of the synthesized SnS NPs and enhanced electrical conductivity of the NPs due to increased tin vacancy. Dielectric experiments on SnS NPs suggested an electronic polarizations effect to be responsible for changing dielectric properties of the particles, in terms of frequency. Finally, photocatalytic experiments revealed that high degradation power can be obtained using In-doped SnS NPs.

Simple eco-friendly synthesis of the surfactant free SnS nanocrystal toward the photoelectrochemical cell application.

PubMed

Huang, Xiaoguang; Woo, Heechul; Wu, Peinian; Hong, Hyo Jin; Jung, Wan Gil; Kim, Bong-Joong; Vanel, Jean-Charles; Choi, Jin Woo

2017-11-28

A simple, low cost, non-toxic and eco-friendly pathway for synthesizing efficient sunlight-driven tin sulfide photocatalyst was studied. SnS nanocrystals were prepared by using mechanical method. The bulk SnS was obtained by evaporation of SnS nanocrystal solution. The synthesized samples were characterized by using XRD, SEM, TEM, UV-vis, and Raman analyses. Well crystallized SnS nanocrystals were verified and the electrochemical characterization was also performed under visible light irradiation. The SnS nanocrystals have shown remarkable photocurrent density of 7.6 mA cm -2 under 100 mW cm -2 which is about 10 times larger than that of the bulk SnS under notably stable operation conditions. Furthermore, the SnS nanocrystals presented higher stability than the bulk form. The IPCE(Incident photon to current conversion efficiency) of 9.3% at 420 nm was obtained for SnS nanocrystal photoanode which is strikingly higher than that of bulk SnS, 0.78%. This work suggests that the enhancement of reacting area by using SnS nanocrystal absorbers could give rise to the improvement of photoelectrochemical cell efficiency.

Intrinsic Ferroelasticity and/or Multiferroicity in Two-Dimensional Phosphorene and Phosphorene Analogues.

PubMed

Wu, Menghao; Zeng, Xiao Cheng

2016-05-11

Phosphorene and phosphorene analogues such as SnS and SnSe monolayers are promising nanoelectronic materials with desired bandgap, high carrier mobility, and anisotropic structures. Here, we show first-principles calculation evidence that these monolayers are potentially the long-sought two-dimensional (2D) materials that can combine electronic transistor characteristic with nonvolatile memory readable/writeable capability at ambient condition. Specifically, phosphorene is predicted to be a 2D intrinsic ferroelastic material with ultrahigh reversible strain, whereas SnS, SnSe, GeS, and GeSe monolayers are multiferroic with coupled ferroelectricity and ferroelasticity. Moreover, their low-switching barriers render room-temperature nonvolatile memory accessible, and their notable structural anisotropy enables ferroelastic or ferroelectric switching readily readable via electrical, thermal, optical, mechanical, or even spintronic detection upon the swapping of the zigzag and armchair direction. In addition, it is predicted that the GeS and GeSe monolayers as well as bulk SnS and SnSe can maintain their ferroelasticity and ferroelectricity (anti-ferroelectricity) beyond the room temperature, suggesting high potential for practical device application.

SnS2 Thin Film Deposition by Spray Pyrolysis

NASA Astrophysics Data System (ADS)

Jaber, Abdallah Yahia; Alamri, Saleh Noaiman; Aida, Mohammed Salah

2012-06-01

Tin disulfide (SnS2) thin films have been synthesized using a simplified spray pyrolysis technique using a perfume atomizer. The films were deposited using two different solutions prepared by the dilution of SnCl2 and thiourea in distilled water and in methanol. The obtained films have a microcrystalline structure. The film deposited using methanol as the solvent is nearly stochiometric SnS2 with a spinel phase having a (001) preferential orientation. The film prepared with an aqueous solution is Sn-rich. Scanning electronic microscopy (SEM) images reveal that the film deposited with the aqueous solution is rough and is formed with large wires. However, the film deposited with methanol is dense and smooth. Conductivity measurements indicate that the aqueous solution leads to an n-type semiconductor, while methanol leads to a p-type semiconductor.

Methodological issues in using data from social networking sites.

PubMed

Leng, Ho Keat

2013-09-01

Social networking sites (SNS) have become increasingly popular in recent years. With the amount of data available on SNS, the potential exists for researchers to use these data for their research. However, like any research method, there are limitations in using data from SNS. First, as members of SNS are not representative of the population, there is the limitation in generalizing the findings to the population. Second, in SNS with a low level of activity, there is also the issue of whether the data are sufficient for analysis. Third, the validity of the postings by members of SNS should be considered, as members of SNS may not be truthful in their responses. In addition, as the environment for SNS favors a quick emotive response as opposed to a cognitive response, the review suggests that the researcher will need to be aware of possibly different behavior when members of a SNS are faced with a high involvement decision. This article concludes that while there is potential in analyzing data from SNS, researchers should be aware of the limitations in using these data.

Enhanced electronic and optical properties of three TMD heterobilayers.

PubMed

Rehman, Shafiq Ur; Ding, Z J

2018-06-20

The physical and chemical properties of monolayers can be tuned by selective combinations so as to be useful for device applications. Here we present a density functional theory study on the structural, electronic and optical properties of three transition metal dichalcogenide (TMD) heterobilayers, ZrS2/HfS2, ZrSe2/HfSe2 and SnS2/SnSe2. These heterobilayers are predicted to be energetically and dynamically stable structures. The band structure calculation result shows that ZrS2/HfS2, ZrSe2/HfSe2 and SnS2/SnSe2 heterobilayers are semiconductors with indirect band gaps. The efficient charge carrier separation in ZrS2/HfS2 and ZrSe2/HfSe2 heterobilayers indicates that they can be employed in energy harvesting devices. Contrary to the previous report on the ZrS2/HfS2 heterobilayer, we found it to have an intrinsic type-II band alignment which is required in p-n junction diodes and tunnel field effect transistors, and the same behavior was observed in ZrSe2/HfSe2 and SnS2/SnSe2 for the first time. The ZrS2/HfS2 and ZrSe2/HfSe2 heterobilayers reveal enhanced optical absorption both in the ultraviolet and visible regions as compared to their respective monolayers, whereas the parallel and perpendicular part of the optical absorption of the SnS2/SnSe2 heterobilayer revealed an anisotropic behavior; the perpendicular part is largely improved in the higher energy region, and the parallel part of the optical absorption is improved in the ultraviolet region.

Hylleraas-Configuration Interaction study of the 1S ground state of the negative Li ion.

PubMed

Sims, James S

2017-12-28

In a previous work Sims and Hagstrom [J. Chem. Phys. 140, 224312 (2014)] reported Hylleraas-Configuration Interaction (Hy-CI) method variational calculations for the neutral atom and positive ion 1 S ground states of the beryllium isoelectronic sequence. The Li - ion, nominally the first member of this series, has a decidedly different electronic structure. This paper reports the results of a large, comparable calculation for the Li - ground state to explore how well the Hy-CI method can represent the more diffuse L shell of Li - which is representative of the Be(2sns) excited states as well. The best non-relativistic energy obtained was -7.500 776 596 hartree, indicating that 10 - 20 nh accuracy is attainable in Hy-CI and that convergence of the r 12 r 34 double cusp is fast and that this correlation type can be accurately represented within the Hy-CI model.

Social networking site usage among childhood cancer survivors--a potential tool for research recruitment?

PubMed

Seltzer, Erica D; Stolley, Melinda R; Mensah, Edward K; Sharp, Lisa K

2014-09-01

The recent and rapid growth of social networking site (SNS) use presents a unique public health opportunity to develop effective strategies for the recruitment of hard-to-reach participants for cancer research studies. This survey investigated childhood cancer survivors' reported use of SNS such as Facebook or MySpace and their perceptions of using SNS, for recruitment into survivorship research. Sixty White, Black, and Hispanic adult childhood cancer survivors (range 18-48 years of age) that were randomly selected from a larger childhood cancer study, the Chicago Healthy Living Study, participated in this pilot survey. Telephone surveys were conducted to understand current SNS activity and attitudes towards using SNS as a cancer research recruitment tool. Seventy percent of participants reported SNS usage of which 80 % were at least weekly users and 79 % reported positive attitudes towards the use of SNS as a recruitment tool for survivorship research. The results of this pilot study revealed that SNS use was high and regular among the childhood cancer survivors sampled. Most had positive attitudes towards using SNS for recruitment of research. The results of this pilot survey suggest that SNS may offer an alternative approach for recruitment of childhood cancer survivors into research.

Characterization of the Shielded Neutron Source at Triangle Universities Nuclear Laboratory

NASA Astrophysics Data System (ADS)

Hobson, Chad; Finch, Sean; Howell, Calvin; Malone, Ron; Tornow, Wernew

2016-09-01

In 2015, Triangle Universities Nuclear Laboratory rebuilt its shielded neutron source (SNS) with the goal of improving neutron beam collimation and reducing neutron and gamma-ray backgrounds. Neutrons are produced via the 2H(d,n)3He reaction and then collimated by heavy shielding to form a beam. The SNS has the ability to produce both a rectangular and circular neutron beam through use of two collimators with different beam apertures. Our work characterized both the neutron beam profiles as well as the neutron and gamma-ray backgrounds at various locations around the SNS. This characterization was performed to provide researchers who use the SNS with beam parameters necessary to plan and conduct an experiment. Vertical and horizontal beam profiles were measured at two different distances from the neutron production cell by scanning a small plastic scintillator across the face of the beam at various energies for each collimator. Background neutron and gamma-ray intensities were measured using time-of-flight techniques at 10 MeV and 16 MeV with the rectangular collimator. We present results on the position and size of neutron beam as well as on the structure and magnitude of the backgrounds.

Tunneling Diode Based on WSe2 /SnS2 Heterostructure Incorporating High Detectivity and Responsivity.

PubMed

Zhou, Xing; Hu, Xiaozong; Zhou, Shasha; Song, Hongyue; Zhang, Qi; Pi, Lejing; Li, Liang; Li, Huiqiao; Lü, Jingtao; Zhai, Tianyou

2018-02-01

van der Waals (vdW) heterostructures based on atomically thin 2D materials have led to a new era in next-generation optoelectronics due to their tailored energy band alignments and ultrathin morphological features, especially in photodetectors. However, these photodetectors often show an inevitable compromise between photodetectivity and photoresponsivity with one high and the other low. Herein, a highly sensitive WSe 2 /SnS 2 photodiode is constructed on BN thin film by exfoliating each material and manually stacking them. The WSe 2 /SnS 2 vdW heterostructure shows ultralow dark currents resulting from the depletion region at the junction and high direct tunneling current when illuminated, which is confirmed by the energy band structures and electrical characteristics fitted with direct tunneling. Thus, the distinctive WSe 2 /SnS 2 vdW heterostructure exhibits both ultrahigh photodetectivity of 1.29 × 10 13 Jones (I ph /I dark ratio of ≈10 6 ) and photoresponsivity of 244 A W -1 at a reverse bias under the illumination of 550 nm light (3.77 mW cm -2 ). © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fabrication of Cu2SnS3 thin films by ethanol-ammonium solution process by doctor-blade technique

NASA Astrophysics Data System (ADS)

Wang, Yaguang; Li, Jianmin; Xue, Cong; Zhang, Yan; Jiang, Guoshun; Liu, Weifeng; Zhu, Changfei

2017-11-01

In the present study, a low-cost and simple method is applied to fabricate Cu2SnS3 (CTS) thin films. Namely CTS thin films are prepared by a doctor-blade method with a slurry dissolving the Cu2O and SnS powders obtained from CBD reaction solution into ethanol-ammonium solvents. Series of characterization methods including XRD, Raman spectra, SEM and UV-Vis analyses are introduced to investigate the phase structure, morphology and optical properties of CTS thin films. As a result, monoclinic CTS films have been obtained with the disappearance of binary phases CuS and SnS2 while increasing the annealing temperature and time, high quality monoclinic CTS thin films consisting of compact and large grains have been successfully prepared by this ethanol-ammonium method. Moreover, the secondary phase Cu2Sn3S7 is also observed during the annealing process. In addition, the post-annealed CTS film with a band-gap about 0.89 eV shows excellent absorbance between 400 and 1200 nm, which is proper for the bottom layer in multi-junction thin film solar cells.[Figure not available: see fulltext.

Opportunities for Neutrino Physics at the Spallation Neutron Source: A White Paper

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bolozdynya, A.; Cavanna, F.; Efremenko, Y.

2012-11-01

The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory, Tennessee, provides an intense flux of neutrinos in the few tens-of-MeV range, with a sharply-pulsed timing structure that is beneficial for background rejection. In this document, the product of a workshop at the SNS in May 2012, we describe this free, high-quality stopped-pion neutrino source and outline various physics that could be done using it. We describe without prioritization some specific experimental configurations that could address these physics topics.

Development of SnS (FTO/CdS/SnS) thin films by nebulizer spray pyrolysis (NSP) for solar cell applications

NASA Astrophysics Data System (ADS)

Arulanantham, A. M. S.; Valanarasu, S.; Jeyadheepan, K.; Ganesh, V.; Shkir, Mohd

2018-01-01

Herein we report a well-organized analysis on various key-properties of SnS thin films for solar cell fabricated by nebulizer spray pyrolysis technique. X-ray diffraction study reveals the polycrystalline nature of deposited films with orthorhombic crystal structure. The crystallite size was calculated and observed to be in the range of 8-28 nm with increasing molarity of precursor solution. The stoichiometry composition of SnS was confirmed by EDX study. SEM/AFM studies divulge the well-covered deposited surface with spherical grains and the size of grains is increasing with concentration and so the roughness. A remarkable decrease in band gap from 2.6 eV to 1.6 eV was noticed by raising the molar concentration from 0.025 M up to 0.075 M. A single strong emission peak at about 825 nm is observed in PL spectra with enhanced intensity which may be attributed to near band edge emission. From the Hall effect measurement, it was found that the SnS thin film exhibits p-type conductivity. The calculated values of resistivity and carrier concentration are 0.729 Ω cm and 3.67 × 1018/cm3 respectively. Furthermore, to study the photovoltaic properties of SnS thin films a heterojunction solar cell, FTO/n-CdS/p-SnS was produced and the conversion efficiency was recorded about 0.01%.

Addictive use of social networking sites can be explained by the interaction of Internet use expectancies, Internet literacy, and psychopathological symptoms

PubMed Central

Wegmann, Elisa; Stodt, Benjamin; Brand, Matthias

2015-01-01

Background and Aims Most people use the Internet in a functional way to achieve certain goals and needs. However, there is an increasing number of people who experience negative consequences like loss of control and distress based on an excessive use of the Internet and its specific online applications. Some approaches postulate similarities with behavioral addictions as well as substance dependencies. They differentiate between a generalized and a specific Internet addiction, such as the pathological use of social networking sites (SIA–SNS). Prior studies particularly identified the use of applications, personal characteristics, and psychopathological symptoms as significant predictors for the development and maintenance of this phenomenon. So far, it remains unclear how psychopathological symptoms like depression and social anxiety interact with individual expectancies of Internet use and capabilities of handling the Internet, summarized as Internet literacy. Methods The current study (N = 334) investigated the interaction of these components in a structural equation model. Results The results indicate that the effects of depression and social anxiety on SIA–SNS were mediated by Internet use expectancies and self-regulation. Discussion Thus, Internet use expectancies seem to be crucial for SIA–SNS, which is in line with prior models. Conclusions SNS use may be reinforced by experienced gratification and relief from negative feelings. Individual competences in handling the Internet may be preventive for the development of SIA–SNS. PMID:26551905

How Relations are Built within a SNS World -- Social Network Analysis on Mixi --

NASA Astrophysics Data System (ADS)

Matsuo, Yutaka; Yasud, Yuki

Our purpose here is to (1) investigate the structure of the personal networks developed on mixi, a Japanese social networking service (SNS), and (2) to consider the governing mechanism which guides participants of a SNS to form an aggregate network. Our findings are as follows:the clustering coefficient of the network is as high as 0.33 while the characteristic path lenght is as low as 5.5. A network among central users (over 300 edges) consist of two cliques, which seems to be very fragile. Community-affiliation network suggests there are several easy-entry communities which later lead users to more high-entry, unique-theme communities. The analysis on connectedness within a community reveals the importance of real-world interaction. Lastly, we depict a probable image of the entire ecology on {\\\\em mixi} among users and communities, which contributes broadly to social systems on the Web.

Children's patterns of emotional reactivity to conflict as explanatory mechanisms in links between interpartner aggression and child physiological functioning.

PubMed

Davies, Patrick T; Sturge-Apple, Melissa L; Cicchetti, Dante; Manning, Liviah G; Zale, Emily

2009-11-01

This paper examined children's fearful, sad, and angry reactivity to interparental conflict as mediators of associations between their exposure to interparental aggression and physiological functioning. Participants included 200 toddlers and their mothers. Assessments of interparental aggression and children's emotional reactivity were derived from maternal surveys and a semi-structured interview. Cortisol levels and cardiac indices of sympathetic nervous system (SNS) and parasympathetic nervous system (PNS) activity were used to assess toddler physiological functioning. Results indicated that toddler exposure to interparental aggression was associated with greater cortisol levels and PNS activity and diminished SNS activity. Toddler angry emotional reactivity mediated associations between interparental aggression and cortisol and PNS functioning. Fearful emotional reactivity was a mediator of the link between interparental aggression and SNS functioning. The results are interpreted within conceptualizations of how exposure and reactivity to family risk organize individual differences in physiological functioning.

Unlocking the potential of SnS2: Transition metal catalyzed utilization of reversible conversion and alloying reactions

NASA Astrophysics Data System (ADS)

Huang, Zhi Xiang; Wang, Ye; Liu, Bo; Kong, Dezhi; Zhang, Jun; Chen, Tupei; Yang, Hui Ying

2017-01-01

The alloying-dealloying reactions of SnS2 proceeds with the initial conversion reaction of SnS2 with lithium that produces Li2S. Unfortunately, due to the electrochemical inactivity of Li2S, the conversion reaction of SnS2 is irreversible, which significantly limit its potential applications in lithium-ion batteries. Herein, a systematic understanding of transition metal molybdenum (Mo) as a catalyst in SnS2 anode is presented. It is found that Mo catalyst is able to efficiently promote the reversible conversion of Sn to SnS2. This leads to the utilization of both conversion and alloying reactions in SnS2 that greatly increases lithium storage capability of SnS2. Mo catalyst is introduced in the form of MoS2 grown directly onto self-assembled vertical SnS2 nanosheets that anchors on three-dimensional graphene (3DG) creating a hierarchal nanostructured named as SnS2/MoS2/3DG. The catalytic effect results in a significantly enhanced electrochemical properties of SnS2/MoS2/3DG; a high initial Coulombic efficiency (81.5%) and high discharge capacities of 960.5 and 495.6 mA h g-1 at current densities of 50 and 1000 mA g-1, respectively. Post cycling investigations using ex situ TEM and XPS analysis verifies the successful conversion reaction of SnS2 mediated by Mo. The successful integration of catalyst on alloying type metal sulfide anode creates a new avenue towards high energy density lithium anodes.

Unlocking the potential of SnS2: Transition metal catalyzed utilization of reversible conversion and alloying reactions.

PubMed

Huang, Zhi Xiang; Wang, Ye; Liu, Bo; Kong, Dezhi; Zhang, Jun; Chen, Tupei; Yang, Hui Ying

2017-01-19

The alloying-dealloying reactions of SnS 2 proceeds with the initial conversion reaction of SnS 2 with lithium that produces Li 2 S. Unfortunately, due to the electrochemical inactivity of Li 2 S, the conversion reaction of SnS 2 is irreversible, which significantly limit its potential applications in lithium-ion batteries. Herein, a systematic understanding of transition metal molybdenum (Mo) as a catalyst in SnS 2 anode is presented. It is found that Mo catalyst is able to efficiently promote the reversible conversion of Sn to SnS 2 . This leads to the utilization of both conversion and alloying reactions in SnS 2 that greatly increases lithium storage capability of SnS 2 . Mo catalyst is introduced in the form of MoS 2 grown directly onto self-assembled vertical SnS 2 nanosheets that anchors on three-dimensional graphene (3DG) creating a hierarchal nanostructured named as SnS 2 /MoS 2 /3DG. The catalytic effect results in a significantly enhanced electrochemical properties of SnS 2 /MoS 2 /3DG; a high initial Coulombic efficiency (81.5%) and high discharge capacities of 960.5 and 495.6 mA h g -1 at current densities of 50 and 1000 mA g -1 , respectively. Post cycling investigations using ex situ TEM and XPS analysis verifies the successful conversion reaction of SnS 2 mediated by Mo. The successful integration of catalyst on alloying type metal sulfide anode creates a new avenue towards high energy density lithium anodes.

The effect of social networking sites on the relationship between perceived social support and depression.

PubMed

McDougall, Matthew A; Walsh, Michael; Wattier, Kristina; Knigge, Ryan; Miller, Lindsey; Stevermer, Michalene; Fogas, Bruce S

2016-12-30

This study examined whether Social Networking Sites (SNSs) have a negative moderator effect on the established relationship between perceived social support and depression in psychiatric inpatients. Survey instruments assessing for depression, perceived social support, and SNS use, were filled out by 301 psychiatric inpatients. Additional data on age, gender, and primary psychiatric diagnosis were collected. A step-wise multiple regression analysis was performed to determine significant interactions. There was no significant interaction of SNS use on the relationship between perceived social support and depression when measured by Social Media Use Integration Scale or by hours of SNS use per day. There was a significant negative relationship between perceived social support and depression, and a significant positive relationship between hours of SNS use per day and depression, measured by the Beck Depression Inventory-II. Limitations include a gender discrepancy among participants, generalizability, recall bias, and SNS measurement. This is the first study to look at SNS use and depression in psychiatric inpatients. SNS use did not affect perceived social support or the protective relationship between perceived social support and depression. Hours of SNS use per day were correlated with depression scores. Future studies between SNS use and depression should quantify daily SNS use. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Social Networking Site Usage Among Childhood Cancer Survivors - A Potential Tool for Research Recruitment?

PubMed Central

Seltzer, Erica D.; Stolley, Melinda R.; Mensah, Edward K.; Sharp, Lisa K.

2014-01-01

Purpose The recent and rapid growth of social networking site (SNS) use presents a unique public health opportunity to develop effective strategies for the recruitment of hard-to-reach participants for cancer research studies. This survey investigated childhood cancer survivors’ reported use of SNS such as facebook or MySpace and their perceptions of using SNS, for recruitment into survivorship research. Methods Sixty White, Black and Hispanic, adult childhood cancer survivors (range 18 – 48 years of age) that were randomly selected from a larger childhood cancer study, the Chicago Healthy Living Study (CHLS), participated in this pilot survey. Telephone surveys were conducted to understand current SNS activity and attitudes towards using SNS as a cancer research recruitment tool. Results Seventy percent of participants reported SNS usage of which 80% were at least weekly users and 79 % reported positive attitudes towards the use of SNS as a recruitment tool for survivorship research. Conclusions and implications for cancer survivors The results of this pilot study revealed that SNS use was high and regular among the childhood cancer survivors sampled. Most had positive attitudes towards using SNS for recruitment of research. The results of this pilot survey suggest that SNS may offer an alternative approach for recruitment of childhood cancer survivors into research. PMID:24532046

Influence of vacuum annealing on the properties of Cu2SnS3 thin films using low cost ultrasonic spray pyrolysis

NASA Astrophysics Data System (ADS)

Rahaman, Sabina; Sunil, M. Anantha; Shaik, Habibuddin; Ghosh, Kaustab

2018-05-01

Deposition of Cu2SnS3 (CTS) thin films is successfully carried out on soda lime glass substrate using low cost ultrasonic spray pyrolysis technique. Vacuum annealing of CTS films is carried out at different temperatures 350°C, 400°C and 450°C. The present work is to study the effect of annealing temperature on the crystal structure, surface morphology and optical properties of CTS thin films. Structural studies confirm the formation of CTS phase. Raman analysis is carried out to study presence of defects with annealing temperature. Optical studies confirm that film prepared at 450°C temperature is suitable as absorber material for photovoltaic applications.

Anisotropic thermoelectric properties of layered compounds in SnX2 (X = S, Se): a promising thermoelectric material.

PubMed

Sun, Bao-Zhen; Ma, Zuju; He, Chao; Wu, Kechen

2015-11-28

Thermoelectrics interconvert heat to electricity and are of great interest in waste heat recovery, solid-state cooling and so on. Here we assessed the potential of SnS2 and SnSe2 as thermoelectric materials at the temperature gradient from 300 to 800 K. Reflecting the crystal structure, the transport coefficients are highly anisotropic between a and c directions, in particular for the electrical conductivity. The preferred direction for both materials is the a direction in TE application. Most strikingly, when 800 K is reached, SnS2 can show a peak power factor (PF) of 15.50 μW cm(-1) K(-2) along the a direction, while a relatively low value (11.72 μW cm(-1) K(-2)) is obtained in the same direction of SnSe2. These values are comparable to those observed in thermoelectrics such as SnSe and SnS. At 300 K, the minimum lattice thermal conductivity (κmin) along the a direction is estimated to be about 0.67 and 0.55 W m(-1) K(-1) for SnS2 and SnSe2, respectively, even lower than the measured lattice thermal conductivity of Bi2Te3 (1.28 W m(-1) K(-1) at 300 K). The reasonable PF and κmin suggest that both SnS2 and SnSe2 are potential thermoelectric materials. Indeed, the estimated peak ZT can approach 0.88 for SnSe2 and a higher value of 0.96 for SnS2 along the a direction at a carrier concentration of 1.94 × 10(19) (SnSe2) vs. 2.87 × 10(19) cm(-3) (SnS2). The best ZT values in SnX2 (X = S, Se) are comparable to that in Bi2Te3 (0.8), a typical thermoelectric material. We hope that this theoretical investigation will provide useful information for further experimental and theoretical studies on optimizing the thermoelectric properties of SnX2 materials.

Carbon-doped SnS2 nanostructure as a high-efficiency solar fuel catalyst under visible light.

PubMed

Shown, Indrajit; Samireddi, Satyanarayana; Chang, Yu-Chung; Putikam, Raghunath; Chang, Po-Han; Sabbah, Amr; Fu, Fang-Yu; Chen, Wei-Fu; Wu, Chih-I; Yu, Tsyr-Yan; Chung, Po-Wen; Lin, M C; Chen, Li-Chyong; Chen, Kuei-Hsien

2018-01-12

Photocatalytic formation of hydrocarbons using solar energy via artificial photosynthesis is a highly desirable renewable-energy source for replacing conventional fossil fuels. Using an L-cysteine-based hydrothermal process, here we synthesize a carbon-doped SnS 2 (SnS 2 -C) metal dichalcogenide nanostructure, which exhibits a highly active and selective photocatalytic conversion of CO 2 to hydrocarbons under visible-light. The interstitial carbon doping induced microstrain in the SnS 2 lattice, resulting in different photophysical properties as compared with undoped SnS 2 . This SnS 2 -C photocatalyst significantly enhances the CO 2 reduction activity under visible light, attaining a photochemical quantum efficiency of above 0.7%. The SnS 2 -C photocatalyst represents an important contribution towards high quantum efficiency artificial photosynthesis based on gas phase photocatalytic CO 2 reduction under visible light, where the in situ carbon-doped SnS 2 nanostructure improves the stability and the light harvesting and charge separation efficiency, and significantly enhances the photocatalytic activity.

A Review of HIV Prevention Studies that Use Social Networking Sites: Implications for Recruitment, Health Promotion Campaigns, and Efficacy Trials.

PubMed

Jones, Jamal; Salazar, Laura F

2016-11-01

This review describes the use of social networking sites (SNS) in the context of primary prevention of HIV. A review was conducted to assess the published literature for HIV interventions using SNS. Sixteen articles describing twelve interventions were included. SNS were instrumental in recruiting hard-to-reach populations within a short amount of time; were able to reach wide audiences beyond the targeted population for HIV prevention campaigns; and helped to significantly reduce sexual risk behaviors and increase HIV testing. SNS are a viable option to recruit hidden populations, engage the target audience, and disseminate HIV prevention messages. Researchers should use SNS to generate sampling frames that can be used to select participants. Practitioners should use SNS to post images of preventive behavior within health promotion campaigns. Researchers should use multiple SNS platforms to engage participants. As more studies are published using SNS for HIV prevention, meta-analyses will be needed.

Synthesis and Raman analysis of SnS nanoparticles synthesized by PVP assisted polyol method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baby, Benjamin Hudson; Mohan, D. Bharathi, E-mail: d.bharathimohan@gmail.com

2015-06-24

SnS film was prepared by a simple drop casting method after synthesizing SnS nanoparticles by using PVP assisted polyol method. Confocal Raman study was carried out for the as deposited and annealed (150, 300 and 400 °C) films at two different excitation wavelengths 514 and 785 nm. At the excitation wavelength of 514 nm, the Raman modes showed for a mixed phase of SnS and SnS{sub 2} up to 150 °C and then only a pure SnS phase was observed up to 400 °C due to the dissociation of SnS{sub 2} in to SnS by releasing S. The increase in intensity ofmore » Raman (A{sub g} and B{sub 3g}) as well as IR (B{sub 3u}) active modes of SnS are observed with increasing annealing temperature at excitation wavelength 785 nm due to the increased crystallinity and inactiveness of SnS{sub 2} modes. X-ray diffraction confirming the formation of a single phase of SnS while the greater homogeneity in both size and shape of SnS nanoparticles were confirmed through surface morphology from SEM.« less

Editor's Highlight: Effects of Intraperitoneal Injection of SnS2 Flowers on Mouse Testicle.

PubMed

Bai, Disi; Li, Qingzhao; Xiong, Yanjie; Zhao, Junjian; Bai, Liyuan; Shen, Peijun; Yuan, Lu; Wu, Ping

2018-02-01

SnS2 nanoflowers (SnS2 NFs) have been widely used in photoelectric and catalytic applications. However, its explosure and reproductive toxicity is unknown. The aim of this study was to investigate the effect of exposure to 3 different sized-SnS2 flowers (dose: 38 mg/kg; size: 50, 80, and 200 nm) in testes of mice for 4 weeks by intraperitoneal injection. Though the body weight of mice treated or not with SnS2 NFs was not different, and SnS2 NFs were distributed to the organs including liver, kidney, spleen, heart, brain, and testis, more distribution SnS2 NFs (50 and 80 nm) were found in testicle tissues compared with SnS2 flowers (200 nm) in those tissues. The results of sperm count and survival analysis, histopathological evaluation, and qRT-PCR detection showed that there was moderate reproductive toxicity induced by the small-sized SnS2 NFs in testicle tissues. Furthermore, elevated malondialdehyde level and decreased superoxide dismutase activity were also observed in the SnS2 NFs (dose: 38 mg/kg; size: 50 and 80 nm) treated groups. Likewise, the qRT-PCR data indicated that SnS2 NFs can induce apoptosis and inflammation responses. Although the pro-inflammation marker of TNF-α, IL-1β, iNOS, and COX-2 at the mRNA levels were higher expression in 50 and 80 nm groups than that in control and 200 nm group, no statistical significance existed between 50 and 80 nm groups. Accordingly, the repeated-dose toxicity of SnS2 NFs in testicle tissues was also observed in a dose-dependent manner by intraperitoneal injection of SnS2 NFs (size: 50 nm; 0.38, 3.8, and 38 mg/kg) for 4 weeks, when determined by sperm count, survival rate, and qRT-PCR analysis. In addition, transmission electron microscopy showed that the ultrastructural abnormalities formed by the small-sized SnS2 NFs in testes were more severe than those formed by the large-sized SnS2 in testes. Taken together, these findings implied that the SnS2 NFs activated inflammation responses that signified apoptosis in murine testes. This study provided useful information for risk analysis and regulation of SnS2 NFs by administration agencies. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Putting up emotional (Facebook) walls? Attachment status and emerging adults' experiences of social networking sites.

PubMed

Nitzburg, George C; Farber, Barry A

2013-11-01

Social networking sites (SNS) like Facebook can increase interpersonal connections but also intensify jealousy, envy, and surveillance behaviors. Attachment styles may help explain differences in experiencing SNS. This study investigated the role of attachment in influencing emerging adults' perceptions and feelings about SNS and their disclosures on SNS. Disorganized and anxious attachment predicted subjects' use of SNS to avoid more personal face-to-face communication, suggesting individuals with these tendencies use SNS to hold relationships at a psychological arm's distance. Anxious attachment also predicted feelings of intimacy when using SNS, perhaps reflecting online needs for comfort from others. A case narrative is presented to show how those with insecure attachment patterns may struggle to avoid interpersonal conflict when being continuously presented with ambiguous social information. © 2013 Wiley Periodicals, Inc.

The Relationship Between Use of Social Network Sites, Online Social Support, and Well-Being: Results From a Six-Wave Longitudinal Study.

PubMed

Utz, Sonja; Breuer, Johannes

2017-01-01

Existing work on the effects of social network sites (SNS) on well-being has often stressed that SNS can help people gain social support from their online networks, which positively affects their well-being. However, the majority of studies in this area have been cross-sectional in nature and/or relied on student samples. Using data from six waves of a longitudinal study with a representative sample of Dutch Internet users, we first examined whether users and nonusers of SNS differ in online social support and well-being (as indicated by life satisfaction and stress). In a second step, we investigated in more detail how SNS use - more specifically, asking for advice and the number of strong ties on these SNS - are related to online social support, stress, and satisfaction with life. Overall, our results provide no evidence for SNS use and online social support affecting either stress or life satisfaction. SNS users reported more online social support than nonusers did, but also higher levels of stress; the two groups did not differ in overall life satisfaction. With regard to the underlying processes, we found positive cross-sectional and longitudinal relationships between asking for advice on SNS and online social support, indicating that SNS can be an effective tool for receiving social support. However, online social support was not related to higher life satisfaction or reduced stress 6 months later; instead, it seems that SNS users with lower life satisfaction and/or higher stress seek more social support online by asking for advice on SNS.

The Relationship Between Use of Social Network Sites, Online Social Support, and Well-Being

PubMed Central

2017-01-01

Abstract. Existing work on the effects of social network sites (SNS) on well-being has often stressed that SNS can help people gain social support from their online networks, which positively affects their well-being. However, the majority of studies in this area have been cross-sectional in nature and/or relied on student samples. Using data from six waves of a longitudinal study with a representative sample of Dutch Internet users, we first examined whether users and nonusers of SNS differ in online social support and well-being (as indicated by life satisfaction and stress). In a second step, we investigated in more detail how SNS use – more specifically, asking for advice and the number of strong ties on these SNS – are related to online social support, stress, and satisfaction with life. Overall, our results provide no evidence for SNS use and online social support affecting either stress or life satisfaction. SNS users reported more online social support than nonusers did, but also higher levels of stress; the two groups did not differ in overall life satisfaction. With regard to the underlying processes, we found positive cross-sectional and longitudinal relationships between asking for advice on SNS and online social support, indicating that SNS can be an effective tool for receiving social support. However, online social support was not related to higher life satisfaction or reduced stress 6 months later; instead, it seems that SNS users with lower life satisfaction and/or higher stress seek more social support online by asking for advice on SNS. PMID:29147141

Beyond "Facebook Addiction": The Role of Cognitive-Related Factors and Psychiatric Distress in Social Networking Site Addiction.

PubMed

Pontes, Halley M; Taylor, Megan; Stavropoulos, Vasileios

2018-04-01

The use of social networking sites (SNSs) is rapidly increasing as billions of individuals use SNS platforms regularly to communicate with other users, follow the news, and play browser games. Given the widespread use of SNS platforms, investigating the potential predictors of addictive SNS use beyond Facebook use has become paramount given that most studies so far focused on "Facebook addiction." In this study, a total of 511 English-speaking SNS users (58.1% young adults aged 20-35 years; 64.6% female) were recruited online and asked to complete a battery of standardized psychometric tools assessing participants' sociodemographic characteristics, SNS preferences and patterns of use, SNS addiction, preference for online social interaction, maladaptive cognitions, fear of missing out (FoMo), dysfunctional emotion regulation, and general psychiatric distress. Overall, about 4.9% (n = 25) of all participants could be classed as having a high SNS addiction risk profile. Moreover, the results further indicated that FoMo (β = 0.38), maladaptive cognitions (β = 0.25), and psychiatric distress (β = 0.12) significantly predicted SNS addiction (i.e., p < 0.0001) and accounted for about 61% of the total variance in SNS addiction, with FoMo providing the strongest predictive contribution over and above the effects of sociodemographic variables and patterns of SNS use. The implications of the present findings were discussed in light of extant literature on behavioral addictions and Facebook addiction and further considerations were provided regarding the potential clinical implications for cognitive-based psychological treatment approaches to SNS addiction.

V-doped SnS2: a new intermediate band material for a better use of the solar spectrum.

PubMed

Wahnón, Perla; Conesa, José C; Palacios, Pablo; Lucena, Raquel; Aguilera, Irene; Seminovski, Yohanna; Fresno, Fernando

2011-12-07

Intermediate band materials can boost photovoltaic efficiency through an increase in photocurrent without photovoltage degradation thanks to the use of two sub-bandgap photons to achieve a full electronic transition from the valence band to the conduction band of a semiconductor structure. After having reported in previous works several transition metal-substituted semiconductors as able to achieve the electronic structure needed for this scheme, we propose at present carrying out this substitution in sulfides that have bandgaps of around 2.0 eV and containing octahedrally coordinated cations such as In or Sn. Specifically, the electronic structure of layered SnS(2) with Sn partially substituted by vanadium is examined here with first principles quantum methods and seen to give favourable characteristics in this respect. The synthesis of this material in nanocrystalline powder form is then undertaken and achieved using solvothermal chemical methods. The insertion of vanadium in SnS(2) is found to produce an absorption spectrum in the UV-Vis-NIR range that displays a new sub-bandgap feature in agreement with the quantum calculations. A photocatalytic reaction-based test verifies that this sub-bandgap absorption produces highly mobile electrons and holes in the material that may be used for the solar energy conversion, giving experimental support to the quantum calculations predictions.

How does personality matter? An investigation of the impact of extraversion on individuals' SNS use.

PubMed

Deng, Shengli; Liu, Yong; Li, Hongxiu; Hu, Feng

2013-08-01

The fast proliferation of social networking sites (SNS) offers Internet users new possibilities for developing and maintaining their social network. Despite a growing interest in SNS, less research attention has been paid to SNS usage from the perspective of personality, that is, the Big Five personality traits. This study develops a model to elucidate how extraversion, an important dimension of personality, affects the perceptions of SNS users and their continuance intention. The research model is empirically tested with answers gained from 221 usable questionnaires. The results indicate that extraversion positively affects perceived satisfaction, supplementary entertainment, and critical mass directly, and indirectly influences both playfulness and SNS continuance intention.

Low-Temperature Electrical Characteristics of Si-Based Device with New Tetrakis NiPc-SNS Active Layer

NASA Astrophysics Data System (ADS)

Yavuz, Arzu Büyükyağci; Carbas, Buket Bezgın; Sönmezoğlu, Savaş; Soylu, Murat

2016-01-01

A new tetrakis 4-(2,5-di-2-thiophen-2-yl-pyrrol-1-yl)-substituted nickel phthalocyanine (NiPc-SNS) has been synthesized. This synthesized NiPc-SNS thin film was deposited on p-type Si substrate using the spin coating method (SCM) to fabricate a NiPc-SNS/ p-Si heterojunction diode. The temperature-dependent electrical characteristics of the NiPc-SNS/ p-Si heterojunction with good rectifying behavior were investigated by current-voltage ( I- V) measurements between 50 K and 300 K. The results indicate that the ideality factor decreases while the barrier height increases with increasing temperature. The barrier inhomogeneity across the NiPc-SNS/ p-Si heterojunction reveals a Gaussian distribution at low temperatures. These results provide further evidence of the more complicated mechanisms occurring in this heterojunction. Based on these findings, NiPc-SNS/ p-Si junction diodes are feasible for use in low-temperature applications.

The pervasiveness, connectedness, and intrusiveness of social network site use among young adolescents.

PubMed

Espinoza, Guadalupe; Juvonen, Jaana

2011-12-01

Young adolescents are quickly becoming avid users of social networking sites (SNSs); however, little is known regarding how they use these sites. The goal of the present study was to examine the extent to which young adolescents use SNSs, with whom they connect via these sites, and whether SNS use disrupts daily functioning. Among 268 middle-school students surveyed, 63% reported having their own profile page on an SNS. On average, adolescents reported having 196 SNS contacts (friends), most of whom were known peers. Young adolescents with an SNS spent most of their time viewing and responding to comments written on their profile page. Among the SNS users, 39% reported getting behind on schoolwork and 37% reported losing sleep at least once because they were visiting an SNS. As SNS use becomes embedded in young teens' daily lives, it is important to better understand how such use affects their daily adaptive functioning.

First comes social networking, then comes marriage? Characteristics of Americans married 2005-2012 who met through social networking sites.

PubMed

Hall, Jeffrey A

2014-05-01

Abstract Although social networking sites (SNS) have become increasingly prevalent and integrated into the lives of users, the role of SNS in courtship is relatively unknown. The present manuscript reports on the characteristics of Americans married between 2005 and 2012 who met through SNS drawn from a weighted national sample (N=18,527). Compared to other online meetings (i.e., dating sites, online communities, one-on-one communication), individuals who met through SNS were younger, married more recently, and were more likely to be African American. Compared with offline meetings, individuals who met through SNS were more likely to be younger, male, African American and Hispanic, married more recently, and frequent Internet users with higher incomes. Trends suggest an increasing proportion of individuals are meeting using SNS, necessitating further research on factors that influence romantic relational development through SNS.

The use of social networking sites for relationship maintenance in long-distance and geographically close romantic relationships.

PubMed

Billedo, Cherrie Joy; Kerkhof, Peter; Finkenauer, Catrin

2015-03-01

Social networking sites (SNS) play an increasingly important role in maintaining geographically close romantic relationships (GCRR). However, knowledge about SNS use in long-distance romantic relationships (LDRR) is still lacking. The present study examined the relative importance of SNS in maintaining LDRR compared to GCRR, particularly with regard to the use of SNS to express involvement (via relational maintenance behaviors) and to gauge a partner's involvement (via partner surveillance and jealousy) in the relationship. An online survey was conducted among predominantly young adult Facebook users who were in a romantic relationship (N=272). Results showed that participants who were in a LDRR reported higher levels of relational maintenance behaviors through SNS than participants who were in a GCRR. Also, as compared to participants who were in a GCRR, participants who were in a LDRR used SNS more for partner surveillance and experienced higher levels of SNS jealousy.

A systematic review of social networking sites: innovative platforms for health research targeting adolescents and young adults.

PubMed

Park, Bu Kyung; Calamaro, Christina

2013-09-01

To review the evidence to determine if social networking sites (SNS) are effective tools for health research in the adolescent and young adult populations. Systematic review of published research articles focused on use of SNS for youth health research. Seventeen articles were selected that met the following criteria: used SNS at any stage of study, participants between 13 and 25 years of age, English language, and both international and national studies. Reviewers categorized selected studies based on the way SNS were used. Utilization of SNS for effectively implementing research with adolescents and young adults include (a) recruitment, (b) intervention, and (c) measurement. Four findings about advantages of using SNS apparent in this review are (a) ease of access to youth, (b) cost effectiveness in recruitment, (c) ease of intervention, and (d) reliable screening venue of mental status and high-risk behaviors. Although this literature review showed relatively minimal research to date on the use of SNS for research targeting adolescents and young adults, the impact of using SNS for health research is of considerable importance for researchers as well as participants. With careful focus, SNS can become a valuable platform to access, recruit, and deliver health interventions in a cost-effective manner to youth populations as well as hard-to-reach minority or underserved populations. The evidence demonstrates the usefulness of SNS as innovative platforms for health promotion among adolescents and young adults. © 2013 Sigma Theta Tau International.

Hepatic, metabolic and toxicity evaluation of repeated oral administration of SnS2 nanoflowers in mice.

PubMed

Bai, Disi; Li, Qingzhao; Xiong, Yanjie; Wang, Chao; Shen, Peijun; Bai, Liyuan; Yuan, Lu; Wu, Ping

2018-05-02

Tin sulphide (SnS2) nanoflowers (NFs) with highly photocatalytic activity for wastewater treatment may lead to potential health hazards via oral routes of human exposure. No studies have reported the hepatic effects of SnS2 NFs on the metabolic function and hepatotoxicity. In this study, we examined the hepatic effects of the oral administration of SnS2 NFs (250-1000 mg/kg) to ICR mice for 14 d, with the particle size ranging from 50 to 200 nm. Serum and liver tissue samples were assayed using biochemical analysis, liver histopathology and metabolic gene expression. The different sizes of SnS2 NFs (250 mg/kg dose), such as 50, 80 and 200 nm, did not induce any adverse hepatic effect related to biochemical parameters or histopathology in the treated mice compared with controls. The oral administration of 50-nm SnS2 NFs at doses of 250, 500 and 1000 mg/kg for 14 d produced dose-dependent hepatotoxicity and inflammatory responses in treated mice. Furthermore, the expression of metabolic genes in the liver tissues was altered, supporting the SnS2 NF-related hepatotoxic phenotype. The oral administration of SnS2 NFs also produced abnormal microstructures in the livers of the treated mice. Taken together, these data indicate that the increased risk of hepatotoxicity in SnS2 NF-treated mice was independent of the particle size but was dependent on their dose. The no-observed-adverse effect level was <250 mg/kg for the 50-nm SnS2 NFs. Our study provides an experimental basis for the safe application of SnS2 NFs.

Characteristics and outcomes of secondary nodules identified on initial computed tomography scan for patients undergoing resection for primary non-small cell lung cancer.

PubMed

Stiles, Brendon M; Schulster, Michael; Nasar, Abu; Paul, Subroto; Lee, Paul C; Port, Jeffrey L; Altorki, Nasser K

2015-01-01

We sought to define the prevalence, malignancy rate, and outcome of secondary nodules (SNs) detected on computed tomography (CT) scan for patients undergoing resection for primary non-small cell lung cancer (NSCLC). In consecutive patients with NSCLC, we reviewed all CT scan reports obtained at diagnosis of the dominant tumor for description of SNs. When resected, pathology was reviewed. Serial CT reports for 2 years postoperatively were evaluated to follow SNs not resected. Among 155 patients, 88 (57%) were found to have SNs. A total of 137 SNs were evaluated (median size, 0.5 cm). Thirty-two nodules were resected at primary resection. Nineteen (61%) resected nodules were benign, whereas 13 (39%) were malignant (8 synchronous primary tumors and 5 lobar metastases). A total of 105 unresected nodules were followed by CT. Of these, 32 (30%) resolved completely, 20 (19%) shrunk, and 28 (27%) were stable, whereas 11 (11%) were lost to follow-up. Fourteen SNs (13%) grew, of which 5 were found to be malignant, each a new primary. Overall 5-year survival was not different between patients with or without SNs (67% vs 64%; P = .88). The prevalence of SNs on CT scan in patients undergoing resection for primary NSCLC is high. Only a low proportion of SNs are ever found to be malignant, predominantly those on the ipsilateral side as the dominant tumor. The presence of SNs has no effect on survival. Patients with SNs, if otherwise appropriately staged, should not be denied surgical therapy. Copyright © 2015. Published by Elsevier Inc.

Online social networking in adolescence: patterns of use in six European countries and links with psychosocial functioning.

PubMed

Tsitsika, Artemis K; Tzavela, Eleni C; Janikian, Mari; Ólafsson, Kjartan; Iordache, Andreea; Schoenmakers, Tim Michaël; Tzavara, Chara; Richardson, Clive

2014-07-01

Online communication tools, such as social networking sites (SNS), have been comprehensively embraced by adolescents and have become a dominant daily social practice. Recognizing SNS as a key context of adolescent development, this study aimed to investigate associations between heavier SNS use, and adolescent competencies and internalizing problems. Data was collected in six European countries: Greece, Spain, Poland, the Netherlands, Romania, and Iceland. Participants were 10,930 adolescents aged 14-17 years (F/M: 5,719/5,211; mean age 15.8 ± .7 years); 62.3% were aged 14-15.9 years and 37.7% were aged 16-17.9 years. Participants reported on their use of online communication tools, and their general competencies and internalizing problems (Youth Self Report). SNS are both ubiquitous--used by 70% of adolescents--and engaging, given that 40% of users spend 2 or more hours daily on SNS (labeled heavier SNS use). Heavier SNS use was associated with more internalizing problems, and the relation was consistently more pronounced among younger adolescents. Moreover, heavier SNS use was associated with lower academic performance and lower activities scores, especially for younger adolescents. In contrast, among older adolescents heavier SNS use was positively associated with offline social competence. Although heavier SNS use is associated with higher social competence for older adolescents, it is also associated with increased internalizing problems and diminished competencies in academics and activities, especially for younger adolescents. Age, capturing developmental differences in social and regulatory skills, appears to moderate the effects of heavier SNS use on adolescent functioning. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Defining a mismatch: differences in usage of social networking sites between medical students and the faculty who teach them.

PubMed

Brisson, Gregory E; Fisher, Matthew J; LaBelle, Mark W; Kozmic, Sarah E

2015-01-01

Use of social networking sites (SNS) by medical students is increasing, and some students lack awareness of pitfalls arising from the intersection of social networking and medicine. Many institutions have developed guidelines on using SNS, but they are insufficient for students. Educators need new methods to train students on the appropriate use of this technology, but more information is needed before implementing change. Differences in SNS usage between students and faculty were examined. The goal was to evaluate four content areas: SNS usage patterns, attitudes regarding activity on SNS, experience with patient interactions online, and awareness of institutional guidelines on use of SNS. A cross-sectional survey took place at Feinberg School of Medicine, Northwestern University, in 2012. Participants included all students and a cohort of faculty who teach them in a class on professionalism. The response rate was 42% by students (300/711) and 78% by faculty (31/40). Of the students, 94% use SNS, compared to 48% of faculty. Students were more likely than faculty to display content they would not want patients to see (57% vs. 27%), report seeing inappropriate content on colleagues' SNS profiles (64% vs. 42%), and ignore harmful postings by colleagues (25% vs. 7%). Faculty were more likely than students to have been approached by patients on SNS (53% vs. 3%). Most participants were unlikely to conduct Internet searches on patients. Students are more likely than faculty to use SNS and use it very differently than faculty. Students would benefit from training on appropriate use of SNS. Topics that should be addressed include editing one's online presence, managing friend requests from patients, dealing with colleagues who post harmful content, conducting Internet searches on patients, and discussion of boundaries to identify potential harms associated with SNS usage. Differences in usage between students and faculty raise questions if faculty are well suited to provide this training.

The Effect of Loneliness on Social Networking Sites Use and Its Related Behaviors.

PubMed

Ranaeiy, Samira; Taghavi, Mohammad Reza; Goodarzi, Mohammad Ali

2016-08-01

The current research was conducted to examine the effect of "Loneliness", on time spent in Social Networking Sites (S.N.S), main reasons for S.N.S use, and its related behaviors. 156 students of Shiraz University voluntarily participated in this research. Loneliness was assessed usingthe UCLA Loneliness scale. 25% of highest scoring students reported that they were lonely whereas 25% of the lowest scoring students were considered to be non-lonely. The positive and negative reasons of using S.N.S were assessed based on Reasons for Internet Use Scale, and internet behaviors were assessed based on Scale of Internet Behaviors. There was no difference in time spent in S.N.S as well as the positive and negative reasons of using S.N.S (contrary to literature), but internet behaviors showed a significant difference between "lonely" and "non-lonely" individuals. "Lonely" and "non-lonely" individuals showed a significant difference in "social aspect" of S.N.S behaviors. There was also a significant difference between "Lonely" and "non-Lonely" individuals in "Negative impact" of S.N.S behaviors. Yet, there seemed to be no difference in "competency and convenience aspect" of S.N.S behaviors. This study suggested that there is no difference between lonely and non-lonely individuals in reasons for using S.N.S and time spent in S.N.S. This finding stands contrary to previous research findings and general literature on the subject In other words, what drives people to S.N.S at the first place shows no significant difference between lonely and non-lonely individuals while after attending S.N.S, social behavior of lonely individuals shows a significant difference which is consistently enhanced online. Lonely people also significantly develop internet-related problems in their daily functioning, including interference with real life socializing.

Sulfurization effect on optical properties of Cu2SNS3 thin films grown by two-stage process

NASA Astrophysics Data System (ADS)

Reddy, G. Phaneendra; Reddy, K. T. Ramakrishna

2017-05-01

A good phase controlled and impurity free two stage process was used to prepare Cu2SnS3 layers on glass substrates. The layers were prepared by sulfurization of sputtered Cu-Sn metallic precursors by varying the sulfurization temperature (Ts) in the range, 150-450°C, keeping the other deposition parameters constant. A complete investigation of the optical properties of the layers with sulfurization temperature was made by using the optical transmittance and reflectance measurements versus wavelength. The absorption coefficient α, was evaluated using the optical data that showed a α > 104 cm-1 for all the as-grown films. The optical bandgap of the as grown layers was determined from the second derivative diffused reflectance spectra that varied from 1.96 eV to 0.99 eV. Consequently, refractive index and extinction coefficient were calculated from Pankov's relations. In addition, the other optical parameters such as the dielectric constants, dissipation factor and also optical conductivity calculated. A detailed analysis of the dependence of all the above parameters on Ts is reported and discussed.

Children’s Patterns of Emotional Reactivity to Conflict as Explanatory Mechanisms in Links Between Interpartner Aggression and Child Physiological Functioning

PubMed Central

Davies, Patrick T.; Sturge-Apple, Melissa L.; Cicchetti, Dante; Manning, Liviah G.; Zale, Emily

2009-01-01

Background This paper examined children’s fearful, sad, and angry reactivity to interparental conflict as mediators of associations between their exposure to interparental aggression and physiological functioning. Methods Participants included 200 toddlers and their mothers. Assessments of interparental aggression and children’s emotional reactivity were derived from maternal surveys and a semi-structured interview. Cortisol levels and cardiac indices of sympathetic nervous system (SNS) and parasympathetic nervous system (PNS) activity were used to assess toddler physiological functioning. Results Results indicated that toddler exposure to interparental aggression was associated with greater cortisol levels and PNS activity and diminished SNS activity. Toddler angry emotional reactivity mediated associations between interparental aggression and cortisol and PNS functioning. Fearful emotional reactivity was a mediator of the link between interparental aggression and SNS functioning. Conclusions The results are interpreted within conceptualizations of how exposure and reactivity to family risk organizing individual differences in physiological functioning. PMID:19744183

Problematic internet use and social networking site use among Dutch adolescents.

PubMed

Jelenchick, Lauren A; Hawk, Skyler T; Moreno, Megan A

2016-02-01

Problematic Internet use (PIU), defined as Internet use that is risky, excessive, or impulsive in nature and leads to adverse life consequences, is an emerging health concern among adolescents worldwide. Social networking site (SNS) use is among the most popular and common Internet use activities for youth; however, risks of SNS use for PIU remain unexplored. The purpose of this study was to determine the prevalence of adolescents at risk for PIU within a national school-based sample of Dutch adolescents and to explore associations between SNS use and PIU. Adolescents were recruited from six public schools in the Netherlands to complete a survey, which included SNS use questions and the Problematic and Risky Internet Use Screening Scale (PRIUSS). Logistic regression models were used to test associations between risk for PIU and demographic or SNS use variables. A total of 474 adolescents participated (98% response rate), and 11% (n=51) of adolescents were at risk for PIU. Risk for PIU was significantly associated with gender (p=0.015), increased age (p=0.034), and posting on SNS more than four times a day (p=0.003). Risk for PIU was not associated with number of SNS profiles, SNS preference or the number of online friends. Findings illustrate high risk groups for PIU includes males and older teens. Findings also illuminate that risk for PIU related to SNS was not associated with a specific SNS or number of SNSs used but was related to one's personal investment in SNSs by posting four or more times a day.

Fabrication Of SNS Weak Links On SOS Substrates

NASA Technical Reports Server (NTRS)

Hunt, Brian D.

1995-01-01

High-quality superconductor/normal-conductor/superconductor (SNS) devices ("weak links") containing epitaxial films of YBa(2)Cu(3)O(7-x) and SrTiO(3) fabricated on silicon-on-sapphire (SOS) substrates with help of improved multilayer buffer system. Process for fabrication of edge-defined SNS weak links described in "Edge-Geometry SNS Devices Made of Y/Ba/Cu" (NPO-18552).

Hot-Chemistry Structural Phase Transformation in Single-Crystal Chalcogenides for Long-Life Lithium Ion Batteries.

PubMed

Hassan, Fathy M; Hu, Qianqian; Fu, Jing; Batmaz, Rasim; Li, Jingde; Yu, Aiping; Xiao, Xingcheng; Chen, Zhongwei

2017-06-21

Tuned chalcogenide single crystals rooted in sulfur-doped graphene were prepared by high-temperature solution chemistry. We present a facile route to synthesize a rod-on-sheet-like nanohybrid as an active anode material and demonstrate its superior performance in lithium ion batteries (LIBs). This nanohybrid contains a nanoassembly of one-dimensional (1D) single-crystalline, orthorhombic SnS onto two-dimensional (2D) sulfur-doped graphene. The 1D nanoscaled SnS with the rodlike single-crystalline structure possesses improved transport properties compared to its 2D hexagonal platelike SnS 2 . Furthermore, we blend this hybrid chalcogenide with biodegradable polymer composite using water as a solvent. Upon drying, the electrodes were subjected to heating in vacuum at 150 °C to induce polymer condensation via formation of carboxylate groups to produce a mechanically robust anode. The LIB using the as-developed anode material can deliver a high volumetric capacity of ∼2350 mA h cm -3 and exhibit superior cycle stability over 1500 cycles as well as a high capacity retention of 85% at a 1 C rate. The excellent battery performance combined with the simplistic, scalable, and green chemistry approach renders this anode material as a very promising candidate for LIB applications.

Empirical analysis of online social networks in the age of Web 2.0

NASA Astrophysics Data System (ADS)

Fu, Feng; Liu, Lianghuan; Wang, Long

2008-01-01

Today the World Wide Web is undergoing a subtle but profound shift to Web 2.0, to become more of a social web. The use of collaborative technologies such as blogs and social networking site (SNS) leads to instant online community in which people communicate rapidly and conveniently with each other. Moreover, there are growing interest and concern regarding the topological structure of these new online social networks. In this paper, we present empirical analysis of statistical properties of two important Chinese online social networks-a blogging network and an SNS open to college students. They are both emerging in the age of Web 2.0. We demonstrate that both networks possess small-world and scale-free features already observed in real-world and artificial networks. In addition, we investigate the distribution of topological distance. Furthermore, we study the correlations between degree (in/out) and degree (in/out), clustering coefficient and degree, popularity (in terms of number of page views) and in-degree (for the blogging network), respectively. We find that the blogging network shows disassortative mixing pattern, whereas the SNS network is an assortative one. Our research may help us to elucidate the self-organizing structural characteristics of these online social networks embedded in technical forms.

A Heterobimetallic W-Ni Complex Containing a Redox-Active W[SNS]2 Metalloligand.

PubMed

Rosenkoetter, Kyle E; Ziller, Joseph W; Heyduk, Alan F

2016-07-05

The tungsten complex W[SNS]2 ([SNS]H3 = bis(2-mercapto-4-methylphenyl)amine) was bound to a Ni(dppe) [dppe = 1,2-bis(diphenylphosphino)ethane] fragment to form the new heterobimetallic complex W[SNS]2Ni(dppe). Characterization of the complex by single-crystal X-ray diffraction revealed the presence of a short W-Ni bond, which renders the complex diamagnetic despite formal tungsten(V) and nickel(I) oxidation states. The W[SNS]2 unit acts as a redox-active metalloligand in the bimetallic complex, which displays four one-electron redox processes by cyclic voltammetry. In the presence of the organic acid 4-cyanoanilinium tetrafluoroborate, W[SNS]2Ni(dppe) catalyzes the electrochemical reduction of protons to hydrogen coincident with the first reduction of the complex.

INCREASED UNDERSTANDING OF BEAM LOSSES FROM THE SNS LINAC PROTON EXPERIMENT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aleksandrov, Alexander V; Shishlo, Andrei P; Plum, Michael A

Beam loss is a major concern for high power hadron accelerators such as the Spallation Neutron Source (SNS). An unexpected beam loss in the SNS superconducting linac (SCL) was observed during the power ramp up and early operation. Intra-beam-stripping (IBS) loss, in which interactions between H- particles within the accelerated bunch strip the outermost electron, was recently identified as a possible cause of the beam loss. A set of experiments using proton beam acceleration in the SNS linac was conducted, which supports IBS as the primary beam loss mechanism in the SNS SCL.

A review of defects and disorder in multinary tetrahedrally bonded semiconductors [Defects and disorder in multinary tetrahedrally bonded semiconductors studied by experiment and theory

DOE PAGES

Baranowski, Lauryn L.; Zawadzki, Pawel; Lany, Stephan; ...

2016-11-10

Defects are critical to understanding the electronic properties of semiconducting compounds, for applications such as light-emitting diodes, transistors, photovoltaics, and thermoelectrics. In this review, we describe our work investigating defects in tetrahedrally bonded, multinary semiconductors, and discuss the place of our research within the context of publications by other groups. We applied experimental and theory techniques to understand point defects, structural disorder, and extended antisite defects in one semiconductor of interest for photovoltaic applications, Cu 2SnS 3. We contrast our findings on Cu 2SnS 3 with other chemically related Cu-Sn-S compounds, as well as structurally related compounds such as Cumore » 2ZnSnS 4 and Cu(In,Ga)Se 2. We find that evaluation of point defects alone is not sufficient to understand defect behavior in multinary tetrahedrally bonded semiconductors. In the case of Cu 2SnS 3 and Cu 2ZnSnS 4, structural disorder and entropy-driven cation clustering can result in nanoscale compositional inhomogeneities which detrimentally impact the electronic transport. Therefore, it is not sufficient to assess only the point defect behavior of new multinary tetrahedrally bonded compounds; effects such as structural disorder and extended antisite defects must also be considered. Altogether, this review provides a framework for evaluating tetrahedrally bonded semiconducting compounds with respect to their defect behavior for photovoltaic and other applications, and suggests new materials that may not be as prone to such imperfections.« less

A review of defects and disorder in multinary tetrahedrally bonded semiconductors [Defects and disorder in multinary tetrahedrally bonded semiconductors studied by experiment and theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baranowski, Lauryn L.; Zawadzki, Pawel; Lany, Stephan

Defects are critical to understanding the electronic properties of semiconducting compounds, for applications such as light-emitting diodes, transistors, photovoltaics, and thermoelectrics. In this review, we describe our work investigating defects in tetrahedrally bonded, multinary semiconductors, and discuss the place of our research within the context of publications by other groups. We applied experimental and theory techniques to understand point defects, structural disorder, and extended antisite defects in one semiconductor of interest for photovoltaic applications, Cu 2SnS 3. We contrast our findings on Cu 2SnS 3 with other chemically related Cu-Sn-S compounds, as well as structurally related compounds such as Cumore » 2ZnSnS 4 and Cu(In,Ga)Se 2. We find that evaluation of point defects alone is not sufficient to understand defect behavior in multinary tetrahedrally bonded semiconductors. In the case of Cu 2SnS 3 and Cu 2ZnSnS 4, structural disorder and entropy-driven cation clustering can result in nanoscale compositional inhomogeneities which detrimentally impact the electronic transport. Therefore, it is not sufficient to assess only the point defect behavior of new multinary tetrahedrally bonded compounds; effects such as structural disorder and extended antisite defects must also be considered. Altogether, this review provides a framework for evaluating tetrahedrally bonded semiconducting compounds with respect to their defect behavior for photovoltaic and other applications, and suggests new materials that may not be as prone to such imperfections.« less

SNS Extraction Fast Kicker System Development

DTIC Science & Technology

2003-06-01

SNS EXTRACTION FAST KICKER SYSTEM DEVELOPMENT * W. Zhang ξ, J. Sandberg, R. Lambiase, Y.Y. Lee, R. Lockey, J. Mi, T. Nehring, C. Pai, N. Tsoupas...Oak Ridge, TN 37831 * SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for...the U.S. Department of Energy. SNS is a partnership of six national laboratories: Argonne, Brookhaven, Jefferson, Lawrence Berkeley, Los Alamos, and

The cost-effectiveness of sacral nerve stimulation (SNS) for the treatment of idiopathic medically refractory overactive bladder (wet) in the UK.

PubMed

Autiero, Silke Walleser; Hallas, Natalie; Betts, Christopher D; Ockrim, Jeremy L

2015-12-01

To estimate the long-term cost-effectiveness of specialised treatment options for medically refractory idiopathic overactive bladder (OAB) wet. The cost-effectiveness of competing treatment options for patients with medically refractory idiopathic OAB wet was estimated from the perspective of the National Health Service in the UK. We compared sacral nerve stimulation (SNS) with percutaneous nerve evaluation (PNE) or tined-lead evaluation (TLE) with optimal medical therapy (OMT), botulinum toxin type A (BoNT-A) injections, and percutaneous tibial nerve stimulation (PTNS). We used a Markov model with a 10-year time horizon for all treatment options with the exception of PTNS, which has a time horizon of 5 years. Costs and effects (measured as quality-adjusted life years) were calculated to derive incremental cost-effectiveness ratios (ICERs). Direct medical resources included are: device and drug acquisition costs, pre-procedure and procedure costs, and the cost of managing adverse events. Deterministic sensitivity analyses were performed to test robustness of results. At 5 years, SNS (PNE or TLE) was more effective and less costly than PTNS. Compared with OMT at 10 years, SNS (PNE or TLE) was more costly and more effective, and compared with BoNT-A, SNS PNE was less costly and more effective, and SNS TLE was more costly and more effective. Decreasing the BoNT-A dose from 150 to 100 IU marginally increased the 10 year ICERs for SNS TLE and PNE (SNS PNE was no longer dominant). However, both SNS options remained cost-effective. In the management of patients with idiopathic OAB wet, the results of this cost-utility analysis favours SNS (PNE or TLE) over PTNS or OMT, and the most efficient treatment strategy is SNS PNE over BoNT-A over a 10-year period. © 2015 The Authors BJU International © 2015 BJU International Published by John Wiley & Sons Ltd.

Patterns of Sympathetic Responses Induced by Different Stress Tasks

PubMed Central

Fechir, M; Schlereth, T; Purat, T; Kritzmann, S; Geber, C; Eberle, T; Gamer, M; Birklein, F

2008-01-01

Stress tasks are used to induce sympathetic nervous system (SNS) arousal. However, the efficacy and the patterns of SNS activation have not been systematically compared between different tasks. Therefore, we analyzed SNS activation during the following stress tasks: Presentation of negative, positive, and – as a control – neutral affective pictures, Color-Word interference test (CWT), mental arithmetic under time limit, singing a song aloud, and giving a spontaneous talk. We examined 11 healthy subjects and recorded the following SNS parameters: Activation of emotional sweating by quantitative sudometry, skin vasoconstriction by laser-Doppler flowmetry, heart rate by ECG, blood pressure by determination of pulse wave transit time (PWTT), and electromyographic (EMG) activity of the trapezius muscle. Moreover, subjective stress ratings were acquired for each task using a visual analog scale. All tasks were felt significantly stressful when compared to viewing neutral pictures. However, SNS activation was not reliable: Affective pictures did not induce a significant SNS response; singing, giving a talk and mental arithmetic selectively increased heart rate and emotional sweating. Only the CWT globally activated the SNS. Regarding all tasks, induction of emotional sweating, increase of heart rate and blood pressure significantly correlated with subjective stress ratings, in contrast to EMG and skin vasoconstriction. Our results show that the activation of the SNS widely varies depending on the stress task. Different stress tasks differently activate the SNS, which is an important finding when considering sympathetic reactions - in clinical situations and in research. PMID:19018304

Experimental and Theoretical Investigations on Intermediate Band in Doped Nano-SnS2

NASA Astrophysics Data System (ADS)

Heiba, Zein K.; Mohamed, Mohamed Bakr; Abdel Kader, M. H.

2018-03-01

Nano-SnS2 and Sn0.75 X 0.25S2 (X = Cr, Fe, Y) have been prepared by thermolysis method. Phase analysis of x-ray diffraction data confirmed the single-phase nature of all prepared samples, with some residual carbon contributing to the background. Rietveld refinement revealed high anisotropy in crystallite size, signifying a cylindrical structure for the particle shape, as confirmed by transmission electron microscopy. The refined occupancies obtained for the doped cations were found to be smaller than the nominal target doping ratio (25%). Fourier-transform infrared spectra showed presence of Sn-S bond in all samples. The energy was found to be 3.42 eV, 3.33 eV, 2.1 eV and 3.14 eV, and 3.62 eV for undoped SnS2 and when doped with Cr, Fe, and Y, respectively. Density functional theory calculations illustrated that Fe-doped SnS2 has two bandgaps [normal and intermediate (IB) bands]. Meanwhile, Sn0.75Fe0.25S2 sample showed anti-Stokes and an extra photoluminescence peak related to the newly created intermediate band (IB) inside the energy gap. On the other hand, pure SnS2 and Sn0.75 X 0.25S2 (X = Cr, Y) samples emitted four photoluminescence subspectra in ultraviolet, violet, and blue regions.

Perceptions of Teachers and Students towards Educational Application of SNS and Its Educational Effects in Middle School Class

ERIC Educational Resources Information Center

Lee, June; Lee, Yunoug; Kim, Mi Hwa

2015-01-01

SNS use by youth is a growing trend. However, there is a lack of studies on how the application of SNS can contribute to learning and public education for youth. As SNS was not originally developed for educational purposes, there is a possibility that it can be used for meaningful educational activity or that its application can lead to the…

Helium Bubble Injection Solution To The Cavitation Damage At The Spallation Neutron Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Francis, M. W.; Ruggles, A. E.

2009-03-10

The Spallation Neutron Source (SNS) is one of the largest science projects in the United States, with total cost near 1.4 Billion Dollars. The limiting factor of the facility had always been assumed to be the lifetime of the target window due to radiation damage. After further investigation, the lifetime of the target was determined not to be limited by radiation damage but by cavitation damage. The cavitation damage derives from pressure waves caused by the beam energy deposition. Vapor bubbles form when low to negative pressures occur in the mercury near the stainless steel target window due to wavemore » interaction with the structure. Collapse of these bubbles can focus wave energy in small liquid jets that erode the window surface. Compressibility of the mercury can be enhanced to reduce the amplitude of the pressure wave caused by the beam energy deposition. To enhance compressibility, small (10 to 30 micron diameter) gas bubbles could be injected into the bulk of the mercury. Solubility and diffusivity parameters of inert gas in mercury are required for a complete mechanical simulation and engineering of these strategies. Using current theoretical models, one obtains a theoretical Henry coefficient of helium in mercury on the order of 3.9E15 Pa-molHg/molHe at 300 K. This low solubility was confirmed by a direct, offline experimental method. Mercury was charged with helium and any pressure change was recorded. Any pressure change was attributed to gas going into solution. Therefore, with the sensitivity of the experiment, a lower limit of 9E12 Pa-molHg/molHe was placed on the mercury-helium system. These values guarantee a stable bubble lifetime needed within the SNS mercury target to mitigate cavitation issues.« less

A fluid response: Alpha-amylase reactions to acute laboratory stress are related to sample timing and saliva flow rate.

PubMed

Nagy, Tamás; van Lien, René; Willemsen, Gonneke; Proctor, Gordon; Efting, Marieke; Fülöp, Márta; Bárdos, György; Veerman, Enno C I; Bosch, Jos A

2015-07-01

Salivary alpha-amylase (sAA) is used as a sympathetic (SNS) stress marker, though its release is likely co-determined by SNS and parasympathetic (PNS) activation. The SNS and PNS show asynchronous changes during acute stressors, and sAA responses may thus vary with sample timing. Thirty-four participants underwent an eight-minute memory task (MT) and cold pressor task (CPT). Cardiovascular SNS (pre-ejection period, blood pressure) and PNS (heart rate variability) activity were monitored continuously. Unstimulated saliva was collected repeatedly during and after each laboratory stressor, and sAA concentration (U/ml) and secretion (U/minute) determined. Both stressors increased anxiety. The MT caused an immediate and continued cardiac SNS activation, but sAA concentration increased at task cessation only (+54%); i.e., when there was SNS-PNS co-activation. During the MT sAA secretion even decreased (-35%) in conjunction with flow rate and vagal tone. The CPT robustly increased blood pressure but not sAA. In summary, sAA fluctuations did not parallel changes in cardiac SNS activity or anxiety. sAA responses seem contingent on sample timing and flow rate, likely involving both SNS and PNS influences. Verification using other stressors and contexts seems warranted. Copyright © 2015 Elsevier B.V. All rights reserved.

Excessive Time on Social Networking Sites and Disordered Eating Behaviors Among Undergraduate Students: Appearance and Weight Esteem as Mediating Pathways.

PubMed

Murray, Marisa; Maras, Danijela; Goldfield, Gary S

2016-12-01

Social networking sites (SNS) are a popular form of communication among undergraduate students. Body image concerns and disordered eating behaviors are also quite prevalent among this population. Maladaptive use of SNS has been associated with disordered eating behaviors; however, the mechanisms remain unclear. The present study examined if body image concerns (e.g., appearance and weight esteem) mediate the relationship between excessive time spent on SNS and disordered eating behaviors (restrained and emotional eating). The sample included 383 (70.2 percent female) undergraduate students (mean age = 23.08 years, standard deviation = 3.09) who completed self-report questionnaires related to SNS engagement, body image, disordered eating behaviors, and demographics. Parallel multiple mediation and moderated mediation analyses revealed that lower weight and appearance esteem mediated the relationship between excessive time on SNS and restrained eating for males and females, whereas appearance esteem mediated the relationship between excessive time on SNS and emotional eating for females only. The study adds to the literature by highlighting mediational pathways and gender differences. Intervention research is needed to determine if teaching undergraduate students more adaptive ways of using SNS or reducing exposure to SNS reduces body dissatisfaction and disordered eating in this high-risk population.

Heterobimetallic complexes of palladium and platinum containing a redox-active W[SNS]2 metalloligand.

PubMed

Rosenkoetter, Kyle E; Ziller, Joseph W; Heyduk, Alan F

2017-05-02

Complexes of the general formula W[SNS] 2 M(dppe) (M = Pd, Pt; [SNS]H 3 = bis(2-mercapto-p-tolyl)amine; dppe = 1,2-bis(diphenylphosphino)ethane) were prepared by combining the corresponding (dppe)MCl 2 synthon with W[SNS] 2 under reducing conditions. X-ray diffraction studies revealed the formation of a heterobimetallic complex supported by a single thiolate bridging ligand and a short metal-metal bond between the tungsten and palladium or platinum. Electrochemical and computational results show that the frontier orbitals lie predominantly on the W[SNS] 2 fragment suggesting that it behaves as a redox-active metalloligand in these complexes.

Template-free synthesis of novel SnS2 array and its superior performances for lithium ion battery

NASA Astrophysics Data System (ADS)

Zhu, Anquan; Qiao, Lulu; Tan, Pengfei; Ma, Yongjin; Liu, Yi; Pan, Jun

2018-05-01

A kind of novel three-dimensional SnS2 array was fabricated by an ethylenediamine (EDA) assisting low-temperature solvothermal method. It was observed that as-obtained SnS2 array was composed of numerous SnS2 nanosheets with the thickness of about 22 nm. When used as lithium ion batteries (LIBs) anode, the SnS2 array displayed remarkable capacities on rate and cycling performances, delivering the rates with reversible capacities of 763.3, 658.6, 593.6, 554.4 and 450.3 mAh g-1 at the current densities of 0.2, 0.5, 1, 2 and 5 A g-1, respectively. Moreover, the satisfactory cycling performance was also disclosed, remaining capacity of 547.8 mAh g-1 after 100th cycle at 0.2 A g-1, better than some reported pure SnS2 nanostructures. Based on the characterization and experimental results, the reasons of such superior electrochemical performances were determined and elaborated. It means that the SnS2 array possesses promising potential on the renewable energy field.

In times of war, adolescents do not fall silent: Teacher-student social network communication in wartime.

PubMed

Ophir, Yaakov; Rosenberg, Hananel; Asterhan, Christa S C; Schwarz, Baruch B

2016-01-01

Exposure to war is associated with psychological disturbances, but ongoing communication between adolescents and teachers may contribute to adolescents' resilience. This study examined the extent and nature of teacher-student communication on Social Network Sites (SNS) during the 2014 Israel-Gaza war. Israeli adolescents (N = 208, 13-18 yrs) completed information about SNS communication. A subset of these (N = 145) completed questionnaires on social rejection and distress sharing on SNS. More than a half (56%) of the respondents communicated with teachers via SNS. The main content category was 'emotional support'. Adolescents' perceived benefits from SNS communication with teachers were associated with distress sharing. Social rejection was negatively associated with emotional support and perceived benefits from SNS communication. We conclude that SNS communication between teachers and students may provide students with easy access to human connections and emotional support, which is likely to contribute to adolescents' resilience in times of war. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Online social networking sites-a novel setting for health promotion?

PubMed

Loss, Julika; Lindacher, Verena; Curbach, Janina

2014-03-01

Among adolescents, online social networking sites (SNS) such as Facebook are popular platforms for social interaction and may therefore be considered as 'novel settings' that could be exploited for health promotion. In this article, we examine the relevant definitions in health promotion and literature in order to analyze whether key characteristics of 'settings for health promotion' and the socio-ecological settings approach can be transferred to SNS. As many of our daily activities have shifted to cyberspace, we argue that online social interaction may gain more importance than geographic closeness for defining a 'setting'. While exposition to positive references to risk behavior by peers may render the SNS environment detrimental to health, SNS may allow people to create their own content and therefore foster participation. However, those health promotion projects delivered on SNS up until today solely relied on health education directed at end users. It remains unclear how health promotion on SNS can meet other requirements of the settings approach (e.g. building partnerships, changing the environment). As yet, one should be cautious in terming SNS a 'setting'. Copyright © 2013 Elsevier Ltd. All rights reserved.

The Research on Informal Learning Model of College Students Based on SNS and Case Study

NASA Astrophysics Data System (ADS)

Lu, Peng; Cong, Xiao; Bi, Fangyan; Zhou, Dongdai

2017-03-01

With the rapid development of network technology, informal learning based on online become the main way for college students to learn a variety of subject knowledge. The favor to the SNS community of students and the characteristics of SNS itself provide a good opportunity for the informal learning of college students. This research first analyzes the related research of the informal learning and SNS, next, discusses the characteristics of informal learning and theoretical basis. Then, it proposed an informal learning model of college students based on SNS according to the support role of SNS to the informal learning of students. Finally, according to the theoretical model and the principles proposed in this study, using the Elgg and related tools which is the open source SNS program to achieve the informal learning community. This research is trying to overcome issues such as the lack of social realism, interactivity, resource transfer mode in the current network informal learning communities, so as to provide a new way of informal learning for college students.

Older adolescents' motivations for social network site use: the influence of gender, group identity, and collective self-esteem.

PubMed

Barker, Valerie

2009-04-01

This study assessed motives for social network site (SNS) use, group belonging, collective self-esteem, and gender effects among older adolescents. Communication with peer group members was the most important motivation for SNS use. Participants high in positive collective self-esteem were strongly motivated to communicate with peer group via SNS. Females were more likely to report high positive collective self-esteem, greater overall use, and SNS use to communicate with peers. Females also posted higher means for group-in-self, passing time, and entertainment. Negative collective self-esteem correlated with social compensation, suggesting that those who felt negatively about their social group used SNS as an alternative to communicating with other group members. Males were more likely than females to report negative collective self-esteem and SNS use for social compensation and social identity gratifications.

It is all about being popular: the effects of need for popularity on social network site use.

PubMed

Utz, Sonja; Tanis, Martin; Vermeulen, Ivar

2012-01-01

Prior research on predictors of social network site (SNS) use has mainly focused on the Big Five, narcissism, and self-esteem. Results have been inconsistent, and variance explained was rather low. Need for popularity (NfP) might be a better predictor of SNS use, because SNSs are ideal venues for people with a high NfP. Study 1 tested NfP, self-esteem, need to belong, entitlement, and vanity as predictors for a range of SNS behaviors; Study 2 replaced entitlement and vanity with narcissism and added the Big Five as predictors. SNS behaviors assessed were grooming, strategic self-presentation, profile enhancement, disclosure of feelings, routine use of SNS, and number of friends. Results showed that NfP was the strongest and most consistent predictor of SNS behaviors. This pattern indicates that NfP plays an important role in SNSs.

Sex differences in the association of social network satisfaction and the risk for type 2 diabetes.

PubMed

Lukaschek, K; Baumert, J; Kruse, J; Meisinger, C; Ladwig, K H

2017-05-02

The role of an individual's social network satisfaction (SNS) in the association of social isolation or living alone and incident type 2 diabetes (T2D) is unclear. We assessed the association of SNS with incident T2D and analysed potential modifications of the SNS-T2D association by social isolation or living alone. The study population (N = 6839 aged 25-74 years without diabetes at baseline) derived from the prospective population-based MONICA/KORA study (1989-2009). Social network satisfaction was assessed by a single item. Cox regression was used to estimate hazard ratios (HR) for SNS separately in men and women. In men with low SNS, risk for incident T2D increased significantly (HR: 2.15, 95% CI: 1.33-3.48, p value 0.002). After additional adjustments for social isolation or living alone, the risk for incident T2D was still significant, albeit less pronounced (HRs 1.85 or 2.05, p values 0.001 or 0.004). The interaction analysis showed an increased T2D risk effect for low SNS compared to high SNS in women living in a partnership (HR: 2.11, 95% CI: 1.00-4.44, p value for interaction: 0.047) and for moderate SNS compared to high SNS in socially connected women (1.56, 1.01-2.39, 0.010). Further research is needed to address the complexities of the perception of social relationships and social interactions, or interdependence, especially when another major public health issue such as T2D is concerned.

Separate and shared sympathetic outflow to white and brown fat coordinately regulates thermoregulation and beige adipocyte recruitment

PubMed Central

Nguyen, Ngoc Ly T.; Barr, Candace L.; Ryu, Vitaly; Cao, Qiang; Bartness, Timothy J.

2017-01-01

White adipose tissue (WAT) and brown adipose tissue (BAT) are innervated and regulated by the sympathetic nervous system (SNS). It is not clear, however, whether there are shared or separate central SNS outflows to WAT and BAT that regulate their function. We injected two isogenic strains of pseudorabies virus, a retrograde transneuronal viral tract tracer, with unique fluorescent reporters into interscapular BAT (IBAT) and inguinal WAT (IWAT) of the same Siberian hamsters to define SNS pathways to both. To test the functional importance of SNS coordinated control of BAT and WAT, we exposed hamsters with denervated SNS nerves to IBAT to 4°C for 16–24 h and measured core and fat temperatures and norepinephrine turnover (NETO) and uncoupling protein 1 (UCP1) expression in fat tissues. Overall, there were more SNS neurons innervating IBAT than IWAT across the neuroaxis. However, there was a greater percentage of singly labeled IWAT neurons in midbrain reticular nuclei than singly labeled IBAT neurons. The hindbrain had ~30–40% of doubly labeled neurons while the forebrain had ~25% suggesting shared SNS circuitry to BAT and WAT across the brain. The raphe nucleus, a key region in thermoregulation, had ~40% doubly labeled neurons. Hamsters with IBAT SNS denervation maintained core body temperature during acute cold challenge and had increased beige adipocyte formation in IWAT. They also had increased IWAT NETO, temperature, and UCP1 expression compared with intact hamsters. These data provide strong neuroanatomical and functional evidence of WAT and BAT SNS cross talk for thermoregulation and beige adipocyte formation. PMID:27881398

Reactivation and reuse of TiO2-SnS2 composite catalyst for solar-driven water treatment.

PubMed

Kovacic, Marin; Kopcic, Nina; Kusic, Hrvoje; Stangar, Urska Lavrencic; Dionysiou, Dionysios D; Bozic, Ana Loncaric

2018-01-01

One of the most important features of photocatalytic materials intended to be used for water treatment is their long-term stability. The study is focused on the application of thermal and chemical treatments for the reactivation of TiO 2 -SnS 2 composite photocatalyst, prepared by hydrothermal synthesis and immobilized on the glass support using titania/silica binder. Such a catalytic system was applied in solar-driven treatment, solar/TiO 2 -SnS 2 /H 2 O 2 , for the purification of water contaminated with diclofenac (DCF). The effectiveness of studied reactivation methods for retaining TiO 2 -SnS 2 activity in consecutive cycles was evaluated on basis of DCF removal and conversion, and TOC removal and mineralization of organic content. Besides these water quality parameters, biodegradability changes in DCF aqueous solution treated by solar/TiO 2 -SnS 2 /H 2 O 2 process using simply reused (air-dried) and thermally and chemically reactivated composite photocatalyst through six consecutive cycles were monitored. It was established that both thermal and chemical reactivation retain TiO 2 -SnS 2 activity in the second cycle of its reuse. However, both treatments caused the alteration in the TiO 2 -SnS 2 morphology due to the partial transformation of visible-active SnS 2 into non-active SnO 2 . Such alteration, repeated through consecutive reactivation and reuse, was reflected through gradual activity loss of TiO 2 -SnS 2 composite in applied solar-driven water treatment.

77 FR 2674 - Airworthiness Directives; Glasflugel Gliders

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-19

... Models Standard Libelle-201B, Club Libelle 205, Mosquito, and Kestrel gliders. This proposed AD results... 205, all S/Ns (2) Kestrel, all S/Ns, except S/N 85, 110, and 125 (3) Mosquito, all S/Ns (4) Standard...

SnS2 films deposited from molecular ink as Cd-free alternative buffer layer for solar cells

NASA Astrophysics Data System (ADS)

Jariwala, Akshay; Chaudhuri, Tapas K.; Toshniwal, Aditi; Patel, Sanjay; Kheraj, Vipul; Ray, Abhijit

2018-05-01

This work investigates the potential of SnS2 as a Cd-free alternative buffer layer for CIGS solar cells. The suitability of SnS2 film as a buffer layer has been evaluated by numerical analysis using SCAPS software. A new simple method for preparation of SnS2 films by dip-coating from molecular ink is reported. The formation of SnS2 is confirmed by Raman spectroscopy. The films are smooth and shiny with roughness of 2-3 nm. The films are n-type with band gap of 2.6 eV and electrical conductivity of 10-3 S/cm.

SNS programming environment user's guide

NASA Technical Reports Server (NTRS)

Tennille, Geoffrey M.; Howser, Lona M.; Humes, D. Creig; Cronin, Catherine K.; Bowen, John T.; Drozdowski, Joseph M.; Utley, Judith A.; Flynn, Theresa M.; Austin, Brenda A.

1992-01-01

The computing environment is briefly described for the Supercomputing Network Subsystem (SNS) of the Central Scientific Computing Complex of NASA Langley. The major SNS computers are a CRAY-2, a CRAY Y-MP, a CONVEX C-210, and a CONVEX C-220. The software is described that is common to all of these computers, including: the UNIX operating system, computer graphics, networking utilities, mass storage, and mathematical libraries. Also described is file management, validation, SNS configuration, documentation, and customer services.

Social media in health professional education: a student perspective on user levels and prospective applications.

PubMed

Maloney, Stephen; Moss, Alan; Ilic, Dragan

2014-12-01

Social Networking Sites (SNS) have seen exponential growth in recent years. The high utilisation of SNS by tertiary students makes them an attractive tool for educational institutions. This study aims to identify health professional students' use and behaviours with SNS, including students' perspectives on potential applications within health professional curricula. Students enrolled in an undergraduate physiotherapy program were invited to take part in an anonymous, online questionnaire at the end of 2012. The survey consisted of 20 items, gathering demographic data, information on current use of SNS, and opinions regarding the application of SNS into education. Both quantitative and qualitative data were gathered. A total of 142 students, from all years of study, completed the online questionnaire. Only two participants were not current users of social media. Facebook and YouTube had been utilised for educational purposes by 97 and 60 % of participants respectively; 85 % believed that SNS could benefit their learning experience. Only five respondents were not interested in following peers, academic staff, clinicians or professional associations on Facebook. Four key themes emerged: peer collaboration, need for separation between personal and professional realms, complimentary learning and enhanced communication. Students wish to make educational connections via SNS, yet expressed a strong desire to maintain privacy, and a distinction between personal and professional lives. Educational utilisation of SNS may improve communication speed and accessibility. Any educator involvement should be viewed with caution.

Development of SnS2/RGO nanosheet composite for cost-effective aqueous hybrid supercapacitors.

PubMed

Chauhan, Himani; Singh, Manoj K; Kumar, Praveen; Hashmi, Safir Ahmad; Deka, Sasanka

2017-01-13

The development of low cost supercapacitor cells with unique capacitive properties is essential for many domestic and industrial purposes. Here we report the first ever application of SnS 2 -reduced graphene oxide (SnS 2 /RGO) layered nanocomposite as a superior electrode material for symmetric aqueous hybrid supercapacitors. We synthesized SnS 2 /RGO nanocomposite comprised of nanosheets of SnS 2 and graphene oxide via a one-pot hydrothermal approach. in situ as-synthesized SnS 2 /RGO is devised for the first time to give high specific capacitance 500 Fg -1 , energy density 16.67 Wh kg -1 and power density 488 W kg -1 . The cell retains 95% charge/discharge cycle stability up to 1000 cycles. In-short, the SnS 2 /RGO nanosheet composite presented is a novel and advanced material for application in high stability moderate value hybrid supercapacitors. All the currently available surveys in literature state the potential applicability of SnS 2 as the anode material for reversible lithium/sodium ion batteries (LIBs/NIBs) but there is a lack of equivalent studies on electrochemical capacitors. We filled up this knowledge gap by the use of the same material in a cost-effective, highly active hybrid supercapacitor application by utilizing its pseudocapacitance property combined with the layered capacitance property of graphene sheets.

Online social networking addiction among college students in Singapore: Comorbidity with behavioral addiction and affective disorder.

PubMed

Tang, Catherine So-Kum; Koh, Yvaine Yee Woen

2017-02-01

This study aimed to determine the prevalence of addiction to social networking sites/platforms (SNS) and its comorbidity with other behavioral addiction and affective disorder among college students in Singapore. 1110 college students (age: M=21.46, SD=1.80) in Singapore completed measures assessing online social networking, unhealthy food intake and shopping addiction as well as depression, anxiety and mania. Descriptive analyses were conducted to investigate the prevalence and comorbidity of behavioral addiction and affective disorder. Chi-square tests were used to examine gender differences. The prevalence rates of SNS, food and shopping addiction were 29.5%, 4.7% and 9.3% respectively for the total sample. SNS addiction was found to co-occur with food addiction (3%), shopping addiction (5%), and both food and shopping addiction (1%). The comorbidity rates of SNS addiction and affective disorder were 21% for depression, 27.7% for anxiety, and 26.1% for mania. Compared with the total sample, students with SNS addiction reported higher comorbidity rates with other behavioral addiction and affective disorder. In general, females as compared to males reported higher comorbidity rates of SNS addiction and affective disorder. SNS addiction has a high prevalence rate among college students in Singapore. Students with SNS addiction were vulnerable to experience other behavior addiction as well as affective disorder, especially among females. Copyright © 2016. Published by Elsevier B.V.

Sympathetic Nervous Regulation of Calcium and Action Potential Alternans in the Intact Heart.

PubMed

Winter, James; Bishop, Martin J; Wilder, Catherine D E; O'Shea, Christopher; Pavlovic, Davor; Shattock, Michael J

2018-01-01

Rationale: Arrhythmogenic cardiac alternans are thought to be an important determinant for the initiation of ventricular fibrillation. There is limited information on the effects of sympathetic nerve stimulation (SNS) on alternans in the intact heart and the conclusions of existing studies, focused on investigating electrical alternans, are conflicted. Meanwhile, several lines of evidence implicate instabilities in Ca handling, not electrical restitution, as the primary mechanism underpinning alternans. Despite this, there have been no studies on Ca alternans and SNS in the intact heart. The present study sought to address this, by application of voltage and Ca optical mapping for the simultaneous study of APD and Ca alternans in the intact guinea pig heart during direct SNS. Objective : To determine the effects of SNS on APD and Ca alternans in the intact guinea pig heart and to examine the mechanism(s) by which the effects of SNS are mediated. Methods and Results : Studies utilized simultaneous voltage and Ca optical mapping in isolated guinea pig hearts with intact innervation. Alternans were induced using a rapid dynamic pacing protocol. SNS was associated with rate-independent shortening of action potential duration (APD) and the suppression of APD and Ca alternans, as indicated by a shift in the alternans threshold to faster pacing rates. Qualitatively similar results were observed with exogenous noradrenaline perfusion. In contrast with previous reports, both SNS and noradrenaline acted to flatten the slope of the electrical restitution curve. Pharmacological block of the slow delayed rectifying potassium current (I Ks ), sufficient to abolish I Ks -mediated APD-adaptation, partially reversed the effects of SNS on pacing-induced alternans. Treatment with cyclopiazonic acid, an inhibitor of the sarco(endo)plasmic reticulum ATPase, had opposite effects to that of SNS, acting to increase susceptibility to alternans, and suggesting that accelerated Ca reuptake into the sarcoplasmic reticulum is a major mechanism by which SNS suppresses alternans in the guinea pig heart. Conclusions : SNS suppresses calcium and action potential alternans in the intact guinea pig heart by an action mediated through accelerated Ca handling and via increased I Ks .

Advancing Materials Science using Neutrons at Oak Ridge National Laboratory

ScienceCinema

Carpenter, John

2018-02-14

Jack Carpenter, pioneer of accelerator-based pulsed spallation neutron sources, talks about neutron science at Oak Ridge National Laboratory (ORNL) and a need for a second target station at the Spallation Neutron Source (SNS). ORNL is the Department of Energy's largest multiprogram science and energy laboratory, and is home to two scientific user facilities serving the neutron science research community: the High Flux Isotope Reactor (HFIR) and SNS. HFIR and SNS provide researchers with unmatched capabilities for understanding the structure and properties of materials, macromolecular and biological systems, and the fundamental physics of the neutron. Neutrons provide a window through which to view materials at a microscopic level that allow researchers to develop better materials and better products. Neutrons enable us to understand materials we use in everyday life. Carpenter explains the need for another station to produce long wavelength neutrons, or cold neutrons, to answer questions that are addressed only with cold neutrons. The second target station is optimized for that purpose. Modern technology depends more and more upon intimate atomic knowledge of materials, and neutrons are an ideal probe.

Electronic and magnetic properties of SnS2 monolayer doped with 4d transition metals

NASA Astrophysics Data System (ADS)

Xiao, Wen-Zhi; Xiao, Gang; Rong, Qing-Yan; Chen, Qiao; Wang, Ling-Ling

2017-09-01

We investigate the electronic structures and magnetic properties of SnS2 monolayers substitutionally doped with 4-d transition-metal through systematic first principles calculations. The doped complexes exhibit interesting electronic and magnetic behaviors, depending on the interplay between crystal field splitting, Hund's rule, and 4d levels. The system doped with Y is nonmagnetic metal. Both the Zr- and Pd-doped systems remain nonmagnetic semiconductors. Doping results in half-metallic states for Nb-, Ru-, Rh-, Ag, and Cd doped cases, and magnetic semiconductors for systems with Mo and Tc dopants. In particular, the Nb- and Mo-doped systems display long-ranged ferromagnetic ordering with Curie temperature above room temperature, which are primarily attributable to the double-exchange mechanism, and the p-d/p-p hybridizations, respectively. Moreover, The Mo-doped system has excellent energetic stability and flexible mechanical stability, and also possesses remarkable dynamic and thermal (500 K) stability. Our studies demonstrate that Nb- and Mo-doped SnS2 monolayers are promising candidates for preparing 2D diluted magnetic semiconductors, and hence will be a helpful clue for experimentalists.

Thickness-controlled electronic structure and thermoelectric performance of ultrathin SnS2 nanosheets.

PubMed

Li, Jun; Shen, Jinni; Ma, Zuju; Wu, Kechen

2017-08-21

The thermoelectric conversion efficiency of a material relies on a dimensionless parameter (ZT = S 2 σT/κ). It is a great challenge in enhancing the ZT value basically due to that the related transport factors of most of the bulk materials are inter-conditioned to each other, making it very difficult to simultaneously optimize these parameters. In this report, the negative correlation between power factor and thermal conductivity of nano-scaled SnS 2 multilayers is predicted by high-level first-principle computations combined with Boltzmann transport theory. By diminishing the thickness of SnS 2 nanosheet to about 3 L, the S and σ along a direction simultaneously increase whereas κ decreases, achieving a high ZT value of 1.87 at 800 K. The microscopic mechanisms for this unusual negative correlation in nano-scaled two dimensional (2D) material are elucidated and attributed to the quantum confinement effect. The results may open a way to explore the high ZT thermoelectric nano-devices for the practical thermoelectric applications.

The suite of small-angle neutron scattering instruments at Oak Ridge National Laboratory

DOE PAGES

Heller, William T.; Cuneo, Matthew J.; Debeer-Schmitt, Lisa M.; ...

2018-02-21

Oak Ridge National Laboratory is home to the High Flux Isotope Reactor (HFIR), a high-flux research reactor, and the Spallation Neutron Source (SNS), the world's most intense source of pulsed neutron beams. The unique co-localization of these two sources provided an opportunity to develop a suite of complementary small-angle neutron scattering instruments for studies of large-scale structures: the GP-SANS and Bio-SANS instruments at the HFIR and the EQ-SANS and TOF-USANS instruments at the SNS. This article provides an overview of the capabilities of the suite of instruments, with specific emphasis on how they complement each other. As a result, amore » description of the plans for future developments including greater integration of the suite into a single point of entry for neutron scattering studies of large-scale structures is also provided.« less

Solar Synthesis of PbS-SnS2 Superstructure Nanoparticles.

PubMed

Brontvein, Olga; Albu-Yaron, Ana; Levy, Moshe; Feuerman, Daniel; Popovitz-Biro, Ronit; Tenne, Reshef; Enyashin, Andrey; Gordon, Jeffrey M

2015-08-25

We report the synthesis and supporting density-functional-theory computations for a closed-cage, misfit layered-compound superstructure from PbS-SnS2, generated by highly concentrated sunlight from a precursor mixture of Pb, SnS2, and graphite. The unique reactor conditions created in our solar furnace are found to be particularly conducive to the formation of these nanomaterials. Detailed structural and chemical characterization revealed a spontaneous inside-out formation mechanism, with a broad range of nonhollow fullerene-like structures starting at a diameter of ∼20 nm and a wall thickness of ∼5 layers. The computations also reveal a counterintuitive charge transfer pathway from the SnS2 layers to the PbS layers, which indicates that, in contrast to binary-layered compounds where it is principally van der Waals forces that hold the layers together, polar forces appear to be as important in stabilizing superstructures of misfit layered compounds.

The suite of small-angle neutron scattering instruments at Oak Ridge National Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heller, William T.; Cuneo, Matthew J.; Debeer-Schmitt, Lisa M.

Oak Ridge National Laboratory is home to the High Flux Isotope Reactor (HFIR), a high-flux research reactor, and the Spallation Neutron Source (SNS), the world's most intense source of pulsed neutron beams. The unique co-localization of these two sources provided an opportunity to develop a suite of complementary small-angle neutron scattering instruments for studies of large-scale structures: the GP-SANS and Bio-SANS instruments at the HFIR and the EQ-SANS and TOF-USANS instruments at the SNS. This article provides an overview of the capabilities of the suite of instruments, with specific emphasis on how they complement each other. As a result, amore » description of the plans for future developments including greater integration of the suite into a single point of entry for neutron scattering studies of large-scale structures is also provided.« less

Help, I Am Losing Control! Examining the Reporting of Sexual Harassment by Adolescents to Social Networking Sites.

PubMed

Van Royen, Kathleen; Poels, Karolien; Vandebosch, Heidi

2016-01-01

Sexual harassment is often encountered by adolescents on social networking sites (SNS). One option to cope with a situation of harassment on SNS is to alarm the provider by reporting the transgressive content. It is yet unclear what the determinants of reporting a sexual harassment situation on SNS are, as well as the subsequent actions to these reports from the part of the SNS provider. In this article, we seek to address these gaps, and in particular examine whether control-by-the-self over the situation and negative emotions play a role in the reporting of sexual harassment on SNS. Findings indicate that a low situational control-by-the-self, indirectly (namely through a higher experience of negative emotions such as anger and shame) increases the reporting of sexual harassment by the victim. Public visibility of the incident and the impossibility to remove the content reduce the situational control-by-the-self. Results further suggest that SNS providers often ignore reported situations of sexual harassment. The study concludes with suggestions for responses to reported harassment on SNS, which should be directed toward increasing behavioral control and thereby alleviating negative emotions.

Thermoelectric SnS and SnS-SnSe solid solutions prepared by mechanical alloying and spark plasma sintering: Anisotropic thermoelectric properties

PubMed Central

Asfandiyar; Wei, Tian-Ran; Li, Zhiliang; Sun, Fu-Hua; Pan, Yu; Wu, Chao-Feng; Farooq, Muhammad Umer; Tang, Huaichao; Li, Fu; Li, Bo; Li, Jing-Feng

2017-01-01

P–type SnS compound and SnS1−xSex solid solutions were prepared by mechanical alloying followed by spark plasma sintering (SPS) and their thermoelectric properties were then studied in different compositions (x = 0.0, 0.2, 0.5, 0.8) along the directions parallel (//) and perpendicular (⊥) to the SPS–pressurizing direction in the temperature range 323–823 Κ. SnS compound and SnS1−xSex solid solutions exhibited anisotropic thermoelectric performance and showed higher power factor and thermal conductivity along the direction ⊥ than the // one. The thermal conductivity decreased with increasing contents of Se and fell to 0.36 W m−1 K−1 at 823 K for the composition SnS0.5Se0.5. With increasing selenium content (x) the formation of solid solutions substantially improved the electrical conductivity due to the increased carrier concentration. Hence, the optimized power factor and reduced thermal conductivity resulted in a maximum ZT value of 0.64 at 823 K for SnS0.2Se0.8 along the parallel direction. PMID:28240324

Soft neurological signs in childhood by measurement of arm movements using acceleration and angular velocity sensors.

PubMed

Kaneko, Miki; Yamashita, Yushiro; Inomoto, Osamu; Iramina, Keiji

2015-10-12

Soft neurological signs (SNS) are evident in the motor performance of children and disappear as the child grows up. Therefore SNS are used as criteria for evaluating age-appropriate development of neurological function. The aim of this study was to quantify SNS during arm movement in childhood. In this study, we focused on pronation and supination, which are arm movements included in the SNS examination. Two hundred and twenty-three typically developing children aged 4-12 years (107 boys, 116 girls) and 18 adults aged 21-26 years (16 males, two females) participated in the experiment. To quantify SNS during pronation and supination, we calculated several evaluation index scores: bimanual symmetry, compliance, postural stability, motor speed and mirror movement. These index scores were evaluated using data obtained from sensors attached to the participants' hands and elbows. Each score increased as age increased. Results obtained using our system showed developmental changes that were consistent with criteria for SNS. We were able to successfully quantify SNS during pronation and supination. These results indicate that it may be possible to use our system as quantitative criteria for evaluating development of neurological function.

Thermoelectric SnS and SnS-SnSe solid solutions prepared by mechanical alloying and spark plasma sintering: Anisotropic thermoelectric properties.

PubMed

Asfandiyar; Wei, Tian-Ran; Li, Zhiliang; Sun, Fu-Hua; Pan, Yu; Wu, Chao-Feng; Farooq, Muhammad Umer; Tang, Huaichao; Li, Fu; Li, Bo; Li, Jing-Feng

2017-02-27

P-type SnS compound and SnS 1-x Se x solid solutions were prepared by mechanical alloying followed by spark plasma sintering (SPS) and their thermoelectric properties were then studied in different compositions (x = 0.0, 0.2, 0.5, 0.8) along the directions parallel (//) and perpendicular (⊥) to the SPS-pressurizing direction in the temperature range 323-823 Κ. SnS compound and SnS 1-x Se x solid solutions exhibited anisotropic thermoelectric performance and showed higher power factor and thermal conductivity along the direction ⊥ than the // one. The thermal conductivity decreased with increasing contents of Se and fell to 0.36 W m -1  K -1 at 823 K for the composition SnS 0.5 Se 0.5 . With increasing selenium content (x) the formation of solid solutions substantially improved the electrical conductivity due to the increased carrier concentration. Hence, the optimized power factor and reduced thermal conductivity resulted in a maximum ZT value of 0.64 at 823 K for SnS 0.2 Se 0.8 along the parallel direction.

Thickness-dependently enhanced photodetection performance of vertically grown SnS2 nanoflakes with large size and high production.

PubMed

Jia, Xiansheng; Tang, Chengchun; Pan, Ruhao; Long, Yun-Ze; Gu, Changzhi; Li, Junjie

2018-05-10

Photodetection based on Two-dimensional (2D) SnS2 has attracted a growing interest due to its superiority in response rate and responsivity, but high-quality growth and high performance photodetecting of 2D SnS2still face great challenges. Here, high-quality SnS2 nanoflakes with large-size and high-production are vertically grown on Si substrate by a modified CVD method, having an average size of 30 m with different thicknesses. Then a single SnS2 nanoflake-based phototransistor was fabricated to obtain a high current on/off ratio of 107 and excellent performances in photodetection, including fast response rates, low dark current, high responsivity and detectivity. Specifically, the SnS2 nanoflakes show the thickness-dependent photodetection capability and the highest responsivity of 354.4 A W-1 is obtained at the average thickness of 100.5 nm. A sensitized process using HfO2 nanolayer can further enhance the responsivity up to 1922 A W-1. Our work provides an efficient path to select SnS2 crystal samples with the optimal thickness as promising candidates for high-performance optoelectronic applications.

Structure, Surface Morphology, and Optical and Electronic Properties of Annealed SnS Thin Films Obtained by CBD

NASA Astrophysics Data System (ADS)

Reghima, Meriem; Akkari, Anis; Guasch, Cathy; Turki-Kamoun, Najoua

2014-09-01

SnS thin films were initially coated onto Pyrex substrates by the chemical bath deposition (CBD) method and annealed at various temperatures ranging from 200°C to 600°C for 30 min in nitrogen gas. X-ray diffraction (XRD) analysis revealed that a structural transition from face-centered cubic to orthorhombic occurs when the annealing temperature is over 500°C. The surface morphology of all thin layers was investigated by means of scanning electron microscopy and atomic force microscopy. The elemental composition of Sn and S, as measured by energy dispersive spectroscopy, is near the stoichiometric ratio. Optical properties studied by means of transmission and reflection measurements show an increase in the absorption coefficient with increasing annealing temperatures. The band gap energy is close to 1.5 eV, which corresponds to the optimum for photovoltaic applications. Last, the thermally stimulated current measurements show that the electrically active traps located in the band gap disappear after annealing at 500°C. These results suggest that, once again, annealing as a post-deposition treatment may be useful for improving the physical properties of the SnS layers included in photovoltaic applications. Moreover, the thermo-stimulated current method may be of practical relevance to explore the electronic properties of more conventional industrial methods, such as sputtering and chemical vapor deposition.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Repins, Ingrid; Mansfield, Lorelle; Kanevce, Ana

Band-edge effects - including grading, electrostatic fluctuations, bandgap fluctuations, and band tails - affect chalcogenide device efficiency. These effects now require more careful consideration as efficiencies increase beyond 20%. Several aspects of the relationships between band-edge phenomena and device performance for NREL absorbers are examined. For Cu(In, Ga)Se2 devices, recent increases in diffusion length imply changes to the optimum bandgap profile. The origin, impact, and modification of electrostatic and bandgap fluctuations are also discussed. The application of the same principles to devices based on CdTe, kesterites, and emerging absorbers (Cu2SnS3, CuSbS2), considering differences in materials properties, is examined.

Future Muon Source Possibilities at the SNS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Williams, Travis J.; MacDougall, Prof. Gregory J.

2017-06-01

The workshop “Future Muon Source Possibilities at the SNS” was held September 1-2, 2016 at Oak Ridge National Laboratory. The workshop aimed to examine the technical feasibility and scientific need to construct a μSR and/or β-NMR facility at the SNS. During the course of the workshop it became evident that recently developed technology could enable the development of a world leading pulsed muon source at SNS, without impacting the neutron science missions of the SNS. The details are discussed below.

(abstract) High-T(sub c) SNS Weak Links Using Oxide Normal Metals

NASA Technical Reports Server (NTRS)

Hunt, B. D.; Barner, J. B.; Foote, M. C.; Vasquez, R. P.

1993-01-01

This work examines device results for edge-geometry SNS weak links utilizing a variety of oxide normal metals. A comparison of the electrical properties of fabricated devices and the magnetic field response will be presented. Device reproducibility will also be discussed. This talk will also examine recent progress in fabrication of epitaxial SNS weak links on silicon-on-sapphire (SOS) substrates. SNS weak links fabricated recently are under investigation, and preliminary results on these devices will be discussed.

Effects of Equivalent Sympathetic Activation during Hypoglycemia on Endothelial Function and Pro-Atherothrombotic Balance in Healthy Individuals and Obese Standard Treated Type 2 Diabetes

PubMed Central

Joy, Nino G.; Mikeladze, Maia; Younk, Lisa M.; Tate, Donna B.; Davis, Stephen N.

2016-01-01

Objective Recent studies in type 2 diabetes have reported an association between hypoglycemia and severe cardiovascular adverse events, which are relatively increased in standard versus intensively treated individuals. The aim of this study was to determine the effects of equivalent sympathetic nervous system (SNS) activity during moderate hypoglycemia on in-vivo endothelial function, pro-inflammatory, pro-atherothrombotic, and pro-coagulant responses in healthy and standard treated type 2 diabetes individuals. Research design and methods Eleven type 2 diabetes and 16 healthy individuals participated in single 2 day studies. Day 1 involved a 2 hr hyperinsulinemic/euglycemic clamp and day 2, a 2 hr hyperinsulinemic/hypoglycemic clamp of 3.2±1 mmol/L in type 2 diabetes and (2.9±0.1 mmol/L) in healthy individuals. Results ICAM-1, VCAM-1, P-selectin, PAI-1, VEGF and endothelin-1 (ET-1) fell during hyperinsulinemic euglycemia but increased during hypoglycemia in type 2 diabetes and healthy individuals. Epinephrine and norepinephrine levels were equivalent during hypoglycemia in type 2 DM and healthy individuals. However, despite similar SNS drive but milder and hypoglycemia there were greater ICAM-1, VCAM-1, PAI-1, VEGF and ET-1 responses in the type 2 diabetes group. Endogenous and exogenous nitric oxide mediated arterial vasodilation were also impaired only during hypoglycemia in type 2 diabetes. Conclusion We conclude that, milder hypoglycemia but equivalent SNS activation results in more diffuse endothelial dysfunction and a greater pro-inflammatory, pro-atherothrombotic and pro-coagulant state in standard treated type 2 diabetes as compared to healthy individuals. PMID:27832858

SIMULATION AND MOCKUP OF SNS JET-FLOW TARGET WITH WALL JET FOR CAVITATION DAMAGE MITIGATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wendel, Mark W; Geoghegan, Patrick J; Felde, David K

2014-01-01

Pressure waves created in liquid mercury pulsed spallation targets at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory induce cavitation damage on the stainless steel target container. The cavitation damage is thought to limit the lifetime of the target for power levels at and above 1 MW. Severe through-wall cavitation damage on an internal wall near the beam entrance window has been observed in spent-targets. Surprisingly though, there is very little damage on the walls that bound an annular mercury channel that wraps around the front and outside of the target. The mercury flow through this channel ismore » characterized by smooth, attached streamlines. One theory to explain this lack of damage is that the uni-directional flow biases the direction of the collapsing cavitation bubble, reducing the impact pressure and subsequent damage. The theory has been reinforced by in-beam separate effects data. For this reason, a second-generation SNS mercury target has been designed with an internal wall jet configuration intended to protect the concave wall where damage has been observed. The wall jet mimics the annular flow channel streamlines, but since the jet is bounded on only one side, the momentum is gradually diffused by the bulk flow interactions as it progresses around the cicular path of the target nose. Numerical simulations of the flow through this jet-flow target have been completed, and a water loop has been assembled with a transparent test target in order to visualize and measure the flow field. This paper presents the wall jet simulation results, as well as early experimental data from the test loop.« less

A Cross-Cultural Examination of SNS Usage Intensity and Managing Interpersonal Relationships Online: The Role of Culture and the Autonomous-Related Self-Construal.

PubMed

Lee, Soon Li; Kim, Jung-Ae; Golden, Karen Jennifer; Kim, Jae-Hwi; Park, Miriam Sang-Ah

2016-01-01

Perception of the autonomy and relatedness of the self may be influenced by one's experiences and social expectations within a particular cultural setting. The present research examined the role of culture and the Autonomous-Related self-construal in predicting for different aspects of Social Networking Sites (SNS) usage in three Asian countries, especially focusing on those aspects serving interpersonal goals. Participants in this cross-cultural study included 305 university students from Malaysia (n = 105), South Korea (n = 113), and China (n = 87). The study explored specific social and interpersonal behaviors on SNS, such as browsing the contacts' profiles, checking for updates, and improving contact with SNS contacts, as well as the intensity of SNS use, hypothesizing that those with high intensity of use in the Asian context may be doing so to achieve the social goal of maintaining contact and keeping updated with friends. Two scales measuring activities on other users' profiles and contact with friends' profiles were developed and validated. As predicted, some cross-cultural differences were found. Koreans were more likely to use SNS to increase contact but tended to spend less time browsing contacts' profiles than the Malaysians and Chinese. The intensity of SNS use differed between the countries as well, where Malaysians reported higher intensity than Koreans and Chinese. Consistent with study predictions, Koreans were found with the highest Autonomous-Related self-construal scores. The Autonomous-Related self-construal predicted SNS intensity. The findings suggest that cultural contexts, along with the way the self is construed in different cultures, may encourage different types of SNS usage. The authors discuss study implications and suggest future research directions.

A Cross-Cultural Examination of SNS Usage Intensity and Managing Interpersonal Relationships Online: The Role of Culture and the Autonomous-Related Self-Construal

PubMed Central

Lee, Soon Li; Kim, Jung-Ae; Golden, Karen Jennifer; Kim, Jae-Hwi; Park, Miriam Sang-Ah

2016-01-01

Perception of the autonomy and relatedness of the self may be influenced by one's experiences and social expectations within a particular cultural setting. The present research examined the role of culture and the Autonomous-Related self-construal in predicting for different aspects of Social Networking Sites (SNS) usage in three Asian countries, especially focusing on those aspects serving interpersonal goals. Participants in this cross-cultural study included 305 university students from Malaysia (n = 105), South Korea (n = 113), and China (n = 87). The study explored specific social and interpersonal behaviors on SNS, such as browsing the contacts' profiles, checking for updates, and improving contact with SNS contacts, as well as the intensity of SNS use, hypothesizing that those with high intensity of use in the Asian context may be doing so to achieve the social goal of maintaining contact and keeping updated with friends. Two scales measuring activities on other users' profiles and contact with friends' profiles were developed and validated. As predicted, some cross-cultural differences were found. Koreans were more likely to use SNS to increase contact but tended to spend less time browsing contacts' profiles than the Malaysians and Chinese. The intensity of SNS use differed between the countries as well, where Malaysians reported higher intensity than Koreans and Chinese. Consistent with study predictions, Koreans were found with the highest Autonomous-Related self-construal scores. The Autonomous-Related self-construal predicted SNS intensity. The findings suggest that cultural contexts, along with the way the self is construed in different cultures, may encourage different types of SNS usage. The authors discuss study implications and suggest future research directions. PMID:27148100

Predictors of Mobile Phone and Social Networking Site Dependency in Adulthood.

PubMed

Burnell, Kaitlyn; Kuther, Tara L

2016-10-01

The present study explored social and psychological predictors of social networking site (SNS) and mobile phone dependency in a sample of emerging adults (ages 18-25, n = 159, M = 21.87, SD = 2.08) and young adults (ages 26-40, n = 97, M = 31.21, SD = 4.11). Path analysis revealed that SNS dependency mediated the relationship of social comparison, SNS support, and impulsivity on mobile phone dependency. Impulsivity also showed direct links to mobile phone dependency. The present findings suggest that individuals with a strong orientation toward social comparison, who perceive a strong sense of support through SNS networks, or who show difficulty with self-regulation may be at risk for SNS and mobile phone dependency.

Synthesis of tin monosulfide (SnS) nanoparticles using surfactant free microemulsion (SFME) with the single microemulsion scheme

NASA Astrophysics Data System (ADS)

Tarkas, Hemant S.; Marathe, Deepak M.; Mahajan, Mrunal S.; Muntaser, Faisal; Patil, Mahendra B.; Tak, Swapnil R.; Sali, Jaydeep V.

2017-02-01

Synthesis of monomorphic, SnS nanoparticles without using a capping agent is a difficult task with chemical route of synthesis. This paper reports on synthesis of tin monosulfide (SnS) nanopartilces with dimension in the quantum-dot regime using surfactant free microemulsion with single microemulsion scheme. This has been achieved by reaction in microreactors in the CME (C: chlorobenzene, M: methanol and E: ethylene glycol) microemulsion system. This is an easy and controllable chemical route for synthesis of SnS nanoparticles. Nanoparticle diameter showed prominent dependence on microemulsion concentration and marginal dependence on microemulsion temperature in the temperature range studied. The SnS nanoparticles formed with this method form stable dispersion in Tolune.

Is use of social networking sites associated with young women's body dissatisfaction and disordered eating? A look at Black-White racial differences.

PubMed

Howard, Lindsay M; Heron, Kristin E; MacIntyre, Rachel I; Myers, Taryn A; Everhart, Robin S

2017-12-01

Maladaptive patterns of social networking site (SNS) use, such as excessive reassurance seeking, are associated with body dissatisfaction and disordered eating. However, it is unclear how these processes play out among different racial groups. This study examined racial differences in SNS use and body dissatisfaction and disordered eating. Black (n=445) and White (n=477) female undergraduates completed online measures of SNS use (frequency and reassurance seeking), body dissatisfaction, and disordered eating. Black women reported less body dissatisfaction, marginally less disordered eating, and less frequent Facebook use than White women; there were no race differences in SNS reassurance seeking. More frequent Facebook use was associated with more body dissatisfaction (but not disordered eating), and more SNS reassurance seeking predicted both more body dissatisfaction and disordered eating. Associations were not moderated by race, suggesting maladaptive SNS use may have negative consequences for both Black and White women. Copyright © 2017 Elsevier Ltd. All rights reserved.

Identification of metabolites of Si-Ni-San, a traditional Chinese medicine formula, in rat plasma and urine using liquid chromatography/diode array detection/triple-quadrupole spectrometry.

PubMed

Yan, Zhixiang; Chen, Ying; Li, Tianxue; Zhang, Jie; Yang, Xinghao

2012-02-15

Si-Ni-San (SNS) is a widely used traditional Chinese medicine formula (TCMF) in treating various diseases. However, the in vivo integrated metabolism of its multiple components remains unknown. In this paper, a liquid chromatography coupled with diode array detection and triple-quadrupole spectrometry (LC-DAD-MS/MS) method was developed for detection and identification of SNS metabolites in rat plasma and urine at a normal clinical dosage. Accurate structural elucidation was performed using MS/MS, UV data and n-octanol/water partition coefficient. Based on the proposed strategy, 36 absorbed compounds and 29 metabolites in plasma and 33 metabolites in urine were detected by a highly sensitive MRM method. Our results indicated that phase II reactions (e.g., methylation, glucuronidation and sulfation) were the main metabolic pathways of gallic acid and flavanones, while phase I reactions (e.g., hydroxylation) were the major metabolic reaction for triterpenoid saponins. The metabolite profile analysis of SNS provided a comprehensive understanding of the in vivo metabolic fates of constituents in SNS. Moreover, the results in this work demonstrated the present strategy based on the combination of chromatographic, spectrophotometric, mass-spectrometric, and software prediction to detect and identify metabolites was effective and reliable. And such a strategy may also be extended to investigate the metabolism of other TCMF. Copyright © 2011 Elsevier B.V. All rights reserved.

Potential benefits and harms of a peer support social network service on the internet for people with depressive tendencies: qualitative content analysis and social network analysis.

PubMed

Takahashi, Yoshimitsu; Uchida, Chiyoko; Miyaki, Koichi; Sakai, Michi; Shimbo, Takuro; Nakayama, Takeo

2009-07-23

Internet peer support groups for depression are becoming popular and could be affected by an increasing number of social network services (SNSs). However, little is known about participant characteristics, social relationships in SNSs, and the reasons for usage. In addition, the effects of SNS participation on people with depression are rather unknown. The aim was to explore the potential benefits and harms of an SNS for depression based on a concurrent triangulation design of mixed methods strategy, including qualitative content analysis and social network analysis. A cross-sectional Internet survey of participants, which involved the collection of SNS log files and a questionnaire, was conducted in an SNS for people with self-reported depressive tendencies in Japan in 2007. Quantitative data, which included user demographics, depressive state, and assessment of the SNS (positive vs not positive), were statistically analyzed. Descriptive contents of responses to open-ended questions concerning advantages and disadvantages of SNS participation were analyzed using the inductive approach of qualitative content analysis. Contents were organized into codes, concepts, categories, and a storyline based on the grounded theory approach. Social relationships, derived from data of "friends," were analyzed using social network analysis, in which network measures and the extent of interpersonal association were calculated based on the social network theory. Each analysis and integration of results were performed through a concurrent triangulation design of mixed methods strategy. There were 105 participants. Median age was 36 years, and 51% (36/71) were male. There were 37 valid respondents; their number of friends and frequency of accessing the SNS were significantly higher than for invalid/nonrespondents (P = .008 and P = .003). Among respondents, 90% (28/31) were mildly, moderately, or severely depressed. Assessment of the SNS was performed by determining the access frequency of the SNS and the number of friends. Qualitative content analysis indicated that user-selectable peer support could be passive, active, and/or interactive based on anonymity or ease of use, and there was the potential harm of a downward depressive spiral triggered by aggravated psychological burden. Social network analysis revealed that users communicated one-on-one with each other or in small groups (five people or less). A downward depressive spiral was related to friends who were moderately or severely depressed and friends with negative assessment of the SNS. An SNS for people with depressive tendencies provides various opportunities to obtain support that meets users' needs. To avoid a downward depressive spiral, we recommend that participants do not use SNSs when they feel that the SNS is not user-selectable, when they get egocentric comments, when friends have a negative assessment of the SNS, or when they have additional psychological burden.

Materials Data on BaAg2SnS4 (SG:23) by Materials Project

DOE Data Explorer

Kristin Persson

2014-07-09

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

Materials Data on Ag8SnS6 (SG:33) by Materials Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kristin Persson

2014-11-02

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

Materials Data on Fe3(SnS4)2 (SG:44) by Materials Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kristin Persson

2016-02-10

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

Materials Data on Co3(SnS)2 (SG:166) by Materials Project

DOE Data Explorer

Kristin Persson

2014-11-02

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

Very large cooperative effects in heterobimetallic titanium-chromium catalysts for ethylene polymerization/copolymerization.

PubMed

Liu, Shaofeng; Motta, Alessandro; Mouat, Aidan R; Delferro, Massimiliano; Marks, Tobin J

2014-07-23

The heterobimetallic complexes, (η(5)-indenyl)[1-Me2Si((t)BuN)TiCl2]-3-CnH2n-[N,N-bis(2-(ethylthio)ethyl)amine]CrCl3 (n = 0, Ti-C0-Cr(SNS); n = 2, Ti-C2-Cr(SNS); n = 6, Ti-C6-Cr(SNS)), (η(5)-indenyl)[1-Me2Si((t)BuN)TiCl2]-3-C2H4-[N,N-bis((o-OMe-C6H4)2P)amine]CrCl3 (Ti-C2-Cr(PNP)), and (η(5)-indenyl)[1-Me2Si((t)BuN)TiCl2]-3-C2H4-[N,N-bis((diethylamine)ethyl)-amine]CrCl3 (Ti-C2-Cr(NNN)), are synthesized, fully characterized, and employed as olefin polymerization catalysts. With ethylene as the feed and MAO as cocatalyst/activator, SNS-based complexes Ti-C0-Cr(SNS), Ti-C2-Cr(SNS), and Ti-C6-Cr(SNS) afford linear low-density polyethylenes (LLDPEs) with exclusive n-butyl branches (6.8-25.8 branches/1000 C), while under identical polymerization conditions Ti-C2-Cr(PNP) and Ti-C2-Cr(NNN) produce polyethylenes with heterogeneous branching (C2, C4, and C≥6) or negligible branching, respectively. Under identical ethylene polymerization conditions, Ti-C0-Cr(SNS) produces polyethylenes with higher activity (4.5× and 6.1×, respectively), Mn (1.3× and 1.8×, respectively), and branch density (1.4× and 3.8×, respectively), than Ti-C2-Cr(SNS) and Ti-C6-Cr(SNS). Versus a CGC(Et)Ti + SNSCr tandem catalyst, Ti-C0-Cr(SNS) yields polyethylene with somewhat lower activity, but with 22.6× higher Mn and 4.0× greater branching density under identical conditions. In ethylene +1-pentene competition experiments, Ti-C0-Cr(SNS) yields 5.5% n-propyl branches and 94.5% n-butyl branches at [1-pentene] = 0.1 M, and the estimated effective local concentration of 1-hexene is ∼8.6 M. In contrast, the tandem CGC(Et)Ti + SNSCr system yields 91.0% n-propyl branches under identical reaction conditions. The homopolymerization and 1-pentene competition results argue that close Ti···Cr spatial proximity together with weak C-H···Ti and C-H···S interactions significantly influence relative 1-hexene enchainment and chain transfer rates, supported by DFT computation, and that such effects are conversion insensitive but cocatalyst and solvent sensitive.

Perceived stress and life satisfaction: social network service use as a moderator.

PubMed

Niu, Qikun; Liu, Yihao; Sheng, Zitong; He, Yue; Shao, Xiaolin

2011-01-01

Social Network Service (SNS) has become a buzzword in recent media coverage with the development of the second generation of Web-based communities. In China, SNS has played an increasingly important role in its users' daily lives, especially among students. With a sample of 471 college students, we tested the direct relationship between perceived stress and life satisfaction using a regression analysis. Moreover, we found SNS use could buffer the negative effect of perceived stress. This study has practical implications on Internet users' SNS use.

Factors Affecting Intention to Use in Social Networking Sites: An Empirical Study on Thai Society

NASA Astrophysics Data System (ADS)

Jairak, Rath; Sahakhunchai, Napath; Jairak, Kallaya; Praneetpolgrang, Prasong

This research aims to explore the factors that affect the intention to use in Social Networking Sites (SNS). We apply the theory of Technology Acceptance Model (TAM), intrinsic motivation, and trust properties to develop the theoretical framework for SNS users' intention. The results show that the important factors influencing SNS users' intention for general purpose and collaborative learning are task-oriented, pleasure-oriented, and familiarity-based trust. In marketing usage, dispositional trust and pleasure-oriented are two main factors that reflect intention to use in SNS.

Efficient Photocatalytic Hydrogen Evolution via Band Alignment Tailoring: Controllable Transition from Type-I to Type-II.

PubMed

Cheng, Zhongzhou; Wang, Fengmei; Shifa, Tofik Ahmed; Jiang, Chao; Liu, Quanlin; He, Jun

2017-11-01

Considering the sizable band gap and wide spectrum response of tin disulfide (SnS 2 ), ultrathin SnS 2 nanosheets are utilized as solar-driven photocatalyst for water splitting. Designing a heterostructure based on SnS 2 is believed to boost their catalytic performance. Unfortunately, it has been quite challenging to explore a material with suitable band alignment using SnS 2 nanomaterials for photocatalytic hydrogen generation. Herein, a new strategy is used to systematically tailor the band alignment in SnS 2 based heterostructure to realize efficient H 2 production under sunlight. A Type-I to Type-II band alignment transition is demonstrated via introducing an interlayer of Ce 2 S 3 , a potential photocatalyst for H 2 evolution, between SnS 2 and CeO 2 . Subsequently, this heterostructure demonstrates tunability in light absorption, charge transfer kinetics, and material stability. The optimized heterostructure (SnS 2 -Ce 2 S 3 -CeO 2 ) exhibits an incredibly strong light absorption ranging from deep UV to infrared light. Significantly, it also shows superior hydrogen generation with the rate of 240 µmol g -1 h -1 under the illumination of simulated sunlight with a very good stability. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chronic sympathetic activation: consequence and cause of age-associated obesity?

PubMed

Seals, Douglas R; Bell, Christopher

2004-02-01

Primary aging in adult humans is associated with a progressive, tonic activation of the peripheral sympathetic nervous system (SNS). The purpose of this SNS activation and its physiological impact are, however, unknown. We hypothesize that the chronic stimulation of the SNS with aging is driven in part by a progressive accumulation of body fat. This "error" is sensed by the central nervous system via increases in adiposity-sensitive humoral signals (e.g., leptin, insulin) that cross the blood-brain barrier, activate subcortical areas involved in the regulation of energy balance (e.g., ventromedial hypothalamus), and stimulate SNS outflow to peripheral tissues. The SNS activation is intended to increase beta-adrenergic thermogenesis in order to expend excess energy as heat rather than by storage of fat. Recent evidence, however, indicates that these adjustments are not effective in augmenting energy expenditure with aging. Indeed, older sedentary adults demonstrate reduced, not increased, beta-adrenergic stimulation of metabolic rate because of reduced tissue responsiveness, presumably mediated by SNS-induced impairment of beta-adrenergic signaling. As a result, age-associated SNS activation, initiated as a consequence of accumulating adiposity with the intent of preventing further fat storage, ironically, may in time evolve into a potential mechanism contributing to the development of obesity with aging.

Sns Moderator Poison Design and Experiment Validation of the Moderator Performance

NASA Astrophysics Data System (ADS)

Lu, W.; Iverson, E. B.; Ferguson, P. D.; Crabtree, J. A.; Gallmeier, F. X.; Remec, I.; Baxter, D. V.; Lavelle, C. M.

2009-08-01

The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory reached 180 kW in August 2007, becoming the brightest pulsed neutron source in the world. At its full power of 1.4 MW, SNS will have thermal neutron fluxes approximately an order of magnitude greater than any existing pulsed spallation source. It thus brings a serious challenge to the lifetime of the moderator poison sheets. The SNS moderators are integrated with the inner reflector plug (IRP) at a cost of $2 million a piece. A replacement of the IRP presents a significant drawback to the facility due to the activation and the operation cost. Although there are many factors limiting the lifetime of the IRP, such as radiation damage to the structural material and helium production in beryllium, the limiting factor is the lifetime of the moderator poison sheets. The current operating target system of SNS was built with thick Gd poison sheets at a projected lifetime of 3 years. A recent design based on the MCNPX calculation proposed to replace the Gd poison sheets with even thicker Cd poison sheets, aiming to extend the poison sheet lifetime from 3 to 4 years accompanied by an approximate 5% gain of the moderator performance. An experiment was carried out to verify the calculated moderator performance at the Low Energy Neutron Source (LENS), Indiana University, where the spectra of two polyethylene moderators were measured. The moderators are Cd-decoupled and are poisoned with 0.8 mm Gd and 1.2 mm Cd, respectively. The preliminary analysis of the experiment data shows that the characteristics of the measured spectra of the Gd- and Cd-poisoned moderators agree well with what the calculation predicted. A better moderator performance is observed in the Cd-poisoned moderator. The measured ratio of Cd over Gd on the moderator performance is in a reasonable agreement with the calculation. Further investigation is underway for a better understanding of the difference between the experiment and the calculation.

Materials Data on Ba2SnS3F2 (SG:62) by Materials Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kristin Persson

2014-11-02

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

Materials Data on Sr2SnS3F2 (SG:62) by Materials Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kristin Persson

2014-11-02

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

Communication inequalities and public health implications of adult social networking site use in the United States.

PubMed

Kontos, Emily Z; Emmons, Karen M; Puleo, Elaine; Viswanath, K

2010-01-01

Social media, and specifically social networking sites (SNSs), are emerging as an important platform for communication and health information exchange. Yet, despite the increase in popularity and use, only a limited number of empirical studies document which segments of the adult population are and are not using social networking sites and with what, if any, affect on health. The purpose of this study is to identify potential communication inequalities in social networking site use among a representative sample of U.S. adults and to examine the association between SNS use and psychological well-being. We analyzed data from the National Cancer Institute's 2007 Health Information National Trends Survey (HINTS). Thirty-five percent of online adults reported SNS use within the past 12 months, and there were no significant differences in SNS use by race/ethnicity or socioeconomic position. Younger age (p = .00) was the most significant predictor of SNS use, while being married (p = .02) and having a history of cancer (p = .02) were associated with a decreased odds of SNS use. SNS use was significantly associated with a 0.80 (p = .00) increment in psychological distress score after controlling for other factors. The absence of inequalities in adult SNS use across race/ethnicity and class offers some support for the continued use of social media to promote public health efforts; however, issues such as the persisting digital divide and potential deleterious effects of SNS use on psychological well-being need to be addressed.

GH replacement therapy and second neoplasms in adult survivors of childhood cancer: a retrospective study from a single institution.

PubMed

Brignardello, E; Felicetti, F; Castiglione, A; Fortunati, N; Matarazzo, P; Biasin, E; Sacerdote, C; Ricardi, U; Fagioli, F; Corrias, A; Arvat, E

2015-02-01

Growth hormone deficiency (GHD) is the most common endocrine late effect observed in childhood cancer survivors (CCS) previously submitted to cranial irradiation. Radiation therapy can also increase the risk of second neoplasms (SNs). Since in previous studies GH replacement therapy was associated with increased incidence of neoplasia, we explored the association between SNs and GH replacement therapy in a cohort of CCS with GHD. Within the clinical cohort of CCS referred to the Transition Unit for Childhood Cancer Survivors of Turin between November 2001 and December 2012, we considered all patients who developed GHD as a consequence of cancer therapies. GHD was always diagnosed in childhood. To evaluate the quality of data, our cohort was linked to the Childhood Cancer Registry of Piedmont. GHD was diagnosed in 49 out of 310 CCS included in our clinical cohort. At least one SN was diagnosed in 14 patients, meningioma and basal cell carcinoma being the most common SNs. The cumulative incidence of SNs was similar in GH-treated and -untreated patients (8 SNs out of 26 GH-treated and 6 out of 23 GH-untreated patients; p = 0.331). Age, sex and paediatric cancer type had no impact on SNs development. In our CCS, GH replacement therapy does not seem to increase the risk of SNs. Anyway, independently from replacement therapy, in these patients we observed an elevated risk of SNs, possibly related to previous radiation therapy, which suggests the need of a close long-term follow-up.

Testing of SNS-032 in a Panel of Human Neuroblastoma Cell Lines with Acquired Resistance to a Broad Range of Drugs.

PubMed

Löschmann, Nadine; Michaelis, Martin; Rothweiler, Florian; Zehner, Richard; Cinatl, Jaroslav; Voges, Yvonne; Sharifi, Mohsen; Riecken, Kristoffer; Meyer, Jochen; von Deimling, Andreas; Fichtner, Iduna; Ghafourian, Taravat; Westermann, Frank; Cinatl, Jindrich

2013-12-01

Novel treatment options are needed for the successful therapy of patients with high-risk neuroblastoma. Here, we investigated the cyclin-dependent kinase (CDK) inhibitor SNS-032 in a panel of 109 neuroblastoma cell lines consisting of 19 parental cell lines and 90 sublines with acquired resistance to 14 different anticancer drugs. Seventy-three percent of the investigated neuroblastoma cell lines and all four investigated primary tumor samples displayed concentrations that reduce cell viability by 50% in the range of the therapeutic plasma levels reported for SNS-032 (<754 nM). Sixty-two percent of the cell lines and two of the primary samples displayed concentrations that reduce cell viability by 90% in this concentration range. SNS-032 also impaired the growth of the multidrug-resistant cisplatin-adapted UKF-NB-3 subline UKF-NB-3(r)CDDP(1000) in mice. ABCB1 expression (but not ABCG2 expression) conferred resistance to SNS-032. The antineuroblastoma effects of SNS-032 did not depend on functional p53. The antineuroblastoma mechanism of SNS-032 included CDK7 and CDK9 inhibition-mediated suppression of RNA synthesis and subsequent depletion of antiapoptotic proteins with a fast turnover rate including X-linked inhibitor of apoptosis (XIAP), myeloid cell leukemia sequence 1 (Mcl-1), baculoviral IAP repeat containing 2 (BIRC2; cIAP-1), and survivin. In conclusion, CDK7 and CDK9 represent promising drug targets and SNS-032 represents a potential treatment option for neuroblastoma including therapy-refractory cases.

Testing of SNS-032 in a Panel of Human Neuroblastoma Cell Lines with Acquired Resistance to a Broad Range of Drugs12

PubMed Central

Löschmann, Nadine; Michaelis, Martin; Rothweiler, Florian; Zehner, Richard; Cinatl, Jaroslav; Voges, Yvonne; Sharifi, Mohsen; Riecken, Kristoffer; Meyer, Jochen; von Deimling, Andreas; Fichtner, Iduna; Ghafourian, Taravat; Westermann, Frank; Cinatl, Jindrich

2013-01-01

Novel treatment options are needed for the successful therapy of patients with high-risk neuroblastoma. Here, we investigated the cyclin-dependent kinase (CDK) inhibitor SNS-032 in a panel of 109 neuroblastoma cell lines consisting of 19 parental cell lines and 90 sublines with acquired resistance to 14 different anticancer drugs. Seventy-three percent of the investigated neuroblastoma cell lines and all four investigated primary tumor samples displayed concentrations that reduce cell viability by 50% in the range of the therapeutic plasma levels reported for SNS-032 (<754 nM). Sixty-two percent of the cell lines and two of the primary samples displayed concentrations that reduce cell viability by 90% in this concentration range. SNS-032 also impaired the growth of the multidrug-resistant cisplatin-adapted UKF-NB-3 subline UKF-NB-3rCDDP1000 in mice. ABCB1 expression (but not ABCG2 expression) conferred resistance to SNS-032. The antineuroblastoma effects of SNS-032 did not depend on functional p53. The antineuroblastoma mechanism of SNS-032 included CDK7 and CDK9 inhibition-mediated suppression of RNA synthesis and subsequent depletion of antiapoptotic proteins with a fast turnover rate including X-linked inhibitor of apoptosis (XIAP), myeloid cell leukemia sequence 1 (Mcl-1), baculoviral IAP repeat containing 2 (BIRC2; cIAP-1), and survivin. In conclusion, CDK7 and CDK9 represent promising drug targets and SNS-032 represents a potential treatment option for neuroblastoma including therapy-refractory cases. PMID:24466371

Communication Inequalities and Public Health Implications of Adult Social Networking Site Use in the United States

PubMed Central

Kontos, Emily Z.; Emmons, Karen M.; Puleo, Elaine; Viswanath, K.

2011-01-01

Background Social media, and specifically social networking sites (SNS), are emerging as an important platform for communication and health information exchange. Yet, despite the increase in popularity and use, only a limited number of empirical studies document which segments of the adult population are and are not using social networking sites and with what, if any, affect on health. Methods The purpose of this study is to identify potential communication inequalities in social networking site use among a representative sample of US adults and to examine the association between SNS-use and psychological well-being. We analyzed data from the National Cancer Institute’s 2007 Health Information National Trends Survey (HINTS). Results Thirty-five percent of online adults reported SNS-use within the past 12 months, and; there were no significant differences in SNS-use by race/ethnicity or socio-economic position. Younger age (p=.00) was the most significant predictor of SNS-use while being married (p=.02) and having a history of cancer (p=.02) were associated with a decreased odds of SNS-use. Social networking site use was significantly associated with a 0.80 (p=.00) increment in psychological distress score after controlling for other factors. Conclusion The absence of inequalities in adult SNS-use across race/ethnicity and class offers some support for the continued use of social media to promote public health efforts; however, issues such as the persisting Digital Divide and potential deleterious effects of SNS-use on psychological well-being need to be addressed. PMID:21154095

A three-dimensional self-assembled SnS 2 -nano-dots@graphene hybrid aerogel as an efficient polysulfide reservoir for high-performance lithium–sulfur batteries

DOE PAGES

Luo, Liu; Chung, Sheng-Heng; Manthiram, Arumugam

2018-01-01

A free-standing self-assembled graphene aerogel embedded with SnS 2 nano-dots (SnS 2 -ND@G) is established as an efficient substrate for high-loading sulfur cathodes with synergistically physical and chemical polysulfide-trapping capability.

Learning through Social Networking Sites--The Critical Role of the Teacher

ERIC Educational Resources Information Center

Callaghan, Noelene; Bower, Matt

2012-01-01

This comparative case study examined factors affecting behaviour and learning in social networking sites (SNS). The behaviour and learning of two classes completing identical SNS based modules of work was observed and compared. All student contributions to the SNS were analysed, with the cognitive process dimension of the Revised Bloom's Taxonomy…

A three-dimensional self-assembled SnS 2 -nano-dots@graphene hybrid aerogel as an efficient polysulfide reservoir for high-performance lithium–sulfur batteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luo, Liu; Chung, Sheng-Heng; Manthiram, Arumugam

A free-standing self-assembled graphene aerogel embedded with SnS 2 nano-dots (SnS 2 -ND@G) is established as an efficient substrate for high-loading sulfur cathodes with synergistically physical and chemical polysulfide-trapping capability.

Validation of a combined health literacy and numeracy instrument for patients with type 2 diabetes.

PubMed

Luo, Huabin; Patil, Shivajirao P; Wu, Qiang; Bell, Ronny A; Cummings, Doyle M; Adams, Alyssa D; Hambidge, Bertha; Craven, Kay; Gao, Fei

2018-05-20

This study aimed to validate a new consolidated measure of health literacy and numeracy (health literacy scale [HLS] plus the subjective numeracy scale [SNS]) in patients with type 2 diabetes (T2DM). A convenience sample (N = 102) of patients with T2DM was recruited from an academic family medicine center in the southeastern US between September-December 2017. Participants completed a questionnaire that included the composite HLS/SNS (22 questions) and a commonly used objective measure of health literacy-S-TOFHLA (40 questions). Internal reliability of the HLS/SNS was assessed using Cronbach's alpha. Criterion and construct validity was assessed against the S-TOFHLA. The composite HLS/SNS had good internal reliability (Cronbach's alpha = 0.83). A confirmatory factor analysis revealed there were four factors in the new instrument. Model fit indices showed good model-data fit (RMSEA = 0.08). The Spearman's rank order correlation coefficient between the HLS/SNS and the S-TOFHLA was 0.45 (p < 0.01). Our study suggests that the composite HLS/SNS is a reliable, valid instrument. Published by Elsevier B.V.

Correlates to sleepiness on night shift among male workers engaged in three-shift work in a chemical plant: its association with sleep practice and job stress.

PubMed

Kageyama, Takayuki; Kobayashi, Toshio; Abe-Gotoh, Ayano

2011-01-01

The purpose of this study was to examine the correlation of sleepiness during night shift (SNS) in male shiftworkers with nonpharmacological self-management (nPSM) practices to facilitate good day sleep, and also with job stress. Sleepiness on the job and possible correlates to SNS among 157 male shiftworkers in a rotating three-shift schedule at a chemical plant were cross-sectionally investigated using a self-administered questionnaire. Multivariate analyses revealed that SNS was positively associated with drinking alcoholic beverages before day sleep, but inversely associated with subjective health status, being of the evening type, abstaining from caffeine before day sleep, having a bath before day sleep, job control, reward from work, feeling suited to the job, and support from colleagues. SNS correlated with certain nPSM practices and also with possible modifiers of job stress. These findings provide clues to developing countermeasures against SNS among shiftworkers. The effects of nPSM practices and job stress management on their day sleep and SNS should be examined in detail.

Self-Assembled Cu-Sn-S Nanotubes with High (De)Lithiation Performance.

PubMed

Lin, Jie; Lim, Jin-Myoung; Youn, Duck Hyun; Kawashima, Kenta; Kim, Jun-Hyuk; Liu, Yang; Guo, Hang; Henkelman, Graeme; Heller, Adam; Mullins, Charles Buddie

2017-10-24

Through a gelation-solvothermal method without heteroadditives, Cu-Sn-S composites self-assemble to form nanotubes, sub-nanotubes, and nanoparticles. The nanotubes with a Cu 3-4 SnS 4 core and Cu 2 SnS 3 shell can tolerate long cycles of expansion/contraction upon lithiation/delithiation, retaining a charge capacity of 774 mAh g -1 after 200 cycles with a high initial Coulombic efficiency of 82.5%. The importance of the Cu component for mitigation of the volume expansion and structural evolution upon lithiation is informed by density functional theory calculations. The self-generated template and calculated results can inspire the design of analogous Cu-M-S (M = metal) nanotubes for lithium batteries or other energy storage systems.

Synthesis and characterisation of co-evaporated tin sulphide thin films

NASA Astrophysics Data System (ADS)

Koteeswara Reddy, N.; Ramesh, K.; Ganesan, R.; Ramakrishna Reddy, K. T.; Gunasekhar, K. R.; Gopal, E. S. R.

2006-04-01

Tin sulphide films were grown at different substrate temperatures by a thermal co-evaporation technique. The crystallinity of the films was evaluated from X-ray diffraction studies. Single-phase SnS films showed a strong (040) orientation with an orthorhombic crystal structure and a grain size of 0.12 μm. The films showed an electrical resistivity of 6.1 Ω cm with an activation energy of 0.26 eV. These films exhibited an optical band gap of 1.37 eV and had a high optical absorption coefficient (>104 cm-1) above the band-gap energy. The results obtained were analysed to evaluate the potentiality of the co-evaporated SnS films as an absorber layer in solar photovoltaic devices.

A correlation study of social network usage among health care students.

PubMed

Suit, Louise; Winkler, Patricia; Campbell, Linda; Pennington, Karen; Szutenbach, Mary Pat; Haight, Robert; Roybal, Deborah; McCollum, Marianne

2015-04-01

Due to anecdotal concerns about adequacy of health professions students' communication skills, health professions faculty at a private university formed an interprofessional research team. The study was designed to explore whether the use of social networking services (SNS) influenced health care students' written and oral communication skills. One hundred thirty-two students participated in the study. Communication skills were assessed by using assignments from a health care ethics course required of all students. Use of SNS was measured with an information technology questionnaire. Contrary to expected findings, this exploratory correlation study found no meaningful relationship between the frequency of SNS usage and oral and written communication skills in health professions students. Future studies of SNS would benefit from a younger and more homogeneous study population to assess the use of SNS for learning versus leisure. Copyright 2015, SLACK Incorporated.

Compulsive use of social networking sites in Belgium: prevalence, profile, and the role of attitude toward work and school.

PubMed

De Cock, Rozane; Vangeel, Jolien; Klein, Annabelle; Minotte, Pascal; Rosas, Omar; Meerkerk, Gert-Jan

2014-03-01

A representative sample (n=1,000) of the Belgian population aged 18 years and older filled out an online questionnaire on their Internet use in general and their use of social networking sites (SNS) in particular. We measured total time spent on the Internet, time spent on SNS, number of SNS profiles, gender, age, schooling level, income, job occupation, and leisure activities, and we integrated several psychological scales such as the Quick Big Five and the Mastery Scale. Hierarchical multiple regression modeling shows that gender and age explain an important part of the compulsive SNS score (5%) as well as psychological scales (20%), but attitude toward school (additional 3%) and income (2.5%) also add to explained variance in predictive models of compulsive SNS use.

Numerical modeling of the SNS H{sup −} ion source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Veitzer, Seth A.; Beckwith, Kristian R. C.; Kundrapu, Madhusudhan

Ion source rf antennas that produce H- ions can fail when plasma heating causes ablation of the insulating coating due to small structural defects such as cracks. Reducing antenna failures that reduce the operating capabilities of the Spallation Neutron Source (SNS) accelerator is one of the top priorities of the SNS H- Source Program at ORNL. Numerical modeling of ion sources can provide techniques for optimizing design in order to reduce antenna failures. There are a number of difficulties in developing accurate models of rf inductive plasmas. First, a large range of spatial and temporal scales must be resolved inmore » order to accurately capture the physics of plasma motion, including the Debye length, rf frequencies on the order of tens of MHz, simulation time scales of many hundreds of rf periods, large device sizes on tens of cm, and ion motions that are thousands of times slower than electrons. This results in large simulation domains with many computational cells for solving plasma and electromagnetic equations, short time steps, and long-duration simulations. In order to reduce the computational requirements, one can develop implicit models for both fields and particle motions (e.g. divergence-preserving ADI methods), various electrostatic models, or magnetohydrodynamic models. We have performed simulations using all three of these methods and have found that fluid models have the greatest potential for giving accurate solutions while still being fast enough to perform long timescale simulations in a reasonable amount of time. We have implemented a number of fluid models with electromagnetics using the simulation tool USim and applied them to modeling the SNS H- ion source. We found that a reduced, single-fluid MHD model with an imposed magnetic field due to the rf antenna current and the confining multi-cusp field generated increased bulk plasma velocities of > 200 m/s in the region of the antenna where ablation is often observed in the SNS source. We report here on comparisons of simulated plasma parameters and code performance using more accurate physical models, such as two-temperature extended MHD models, for both a related benchmark system describing a inductively coupled plasma reactor, and for the SNS ion source. We also present results from scaling studies for mesh generation and solvers in the USim simulation code.« less

Discovering the influential users oriented to viral marketing based on online social networks

NASA Astrophysics Data System (ADS)

Zhu, Zhiguo

2013-08-01

The target of viral marketing on the platform of popular online social networks is to rapidly propagate marketing information at lower cost and increase sales, in which a key problem is how to precisely discover the most influential users in the process of information diffusion. A novel method is proposed in this paper for helping companies to identify such users as seeds to maximize information diffusion in the viral marketing. Firstly, the user trust network oriented to viral marketing and users’ combined interest degree in the network including isolated users are extensively defined. Next, we construct a model considering the time factor to simulate the process of information diffusion in viral marketing and propose a dynamic algorithm description. Finally, experiments are conducted with a real dataset extracted from the famous SNS website Epinions. The experimental results indicate that the proposed algorithm has better scalability and is less time-consuming. Compared with the classical model, the proposed algorithm achieved a better performance than does the classical method on the two aspects of network coverage rate and time-consumption in our four sub-datasets.

Studies of molecular diffusion in single-supported bilayer lipid membranes at low hydration by quasielastic neutron scattering

NASA Astrophysics Data System (ADS)

Miskowiec, A.; Bai, M.; Lever, M.; Taub, H.; Hansen, F. Y.; Jenkins, T.; Tyagi, M.; Neumann, D. A.; Diallo, S. O.; Mamontov, E.; Herwig, K. W.

2011-03-01

We have extended our investigation of the quasielastic neutron scattering from single-supported bilayer lipid membranes to a sample of lower hydration using the backscattering spectrometer BASIS at the SNS of ORNL. To focus on the diffusive motion of the water, tail-deuterated DMPC membranes were deposited onto Si O2 -coated Si(100) substrates and characterized by AFM. Compared to a sample of higher hydration, the dryer sample does not have a step-like freezing transition at ~ 267 K and shows less intensity at higher temperatures of a broad Lorentzian component representing bulk-like water. However, the broad component of the ``wet'' and ``dry'' samples behaves similarly at lower temperatures. The dryer sample also shows evidence of a narrow Lorentzian component that has a different temperature dependence than that attributed to conformational changes of the alkyl tails of the lipid molecules in the wet sample. We tentatively identify this slower diffusive motion (time scale ~ 1 ns) with water more tightly bound to the membrane. Supported by NSF Grant No. DMR-0705974.

Three-year cost-effectiveness model for non-animal stabilized hyaluronic acid and dextranomer copolymer compared with sacral nerve stimulation after conservative therapy for the management of fecal incontinence.

PubMed

Bernstein, Mitchell A; Purdy, Christopher H; Becker, Alison; Magar, Raf

2014-06-01

Two new therapies for fecal incontinence (FI) are now available: non-animal stabilized hyaluronic acid and dextranomer copolymer (NASHA/Dx) and sacral nerve stimulation (SNS). This study aimed to determine the cost-effectiveness of NASHA/Dx compared with SNS and conservative therapy (CT) for the treatment of FI after CT failure. Decision tree models with Markov subbranches were developed to compare all direct costs and outcomes during a 3-year period from the viewpoint of the US third-party payer. Costs (in 2013 US dollars) of devices, medical and surgical care, and hospitalization were included. Outcomes included quality-adjusted life-years (QALYs) and incontinence-free days (IFDs). Both costs and outcomes were discounted at an annual rate of 3%. The incremental cost-effectiveness ratio was calculated for each outcome. One-way and probabilistic sensitivity analyses were performed to examine robustness of results and model stability. A budget impact analysis was also undertaken to estimate the potential cost and savings of NASHA/Dx for a payer with 1,000,000 covered lives. For the 3-year cost-effectiveness models, the expected cost was $9053 for CT, $14,962 for NASHA/Dx, and $33,201 for SNS. The numbers of QALYs were 1.769, 1.929, and 2.004, respectively. The numbers of IFDs were 128.8, 267.6, and 514.8, respectively. The incremental cost-effectiveness ratios per additional IFD gained were $42.60 for NASHA/Dx vs CT, $73.76 for SNS vs NASHA/Dx, and $62.55 for SNS vs CT. The incremental costs per QALY gained were $37,036 for NASHA/Dx vs CT, $244,509 for SNS vs NASHA/Dx, and $103,066 for SNS vs CT. The budget impact analysis evaluated the financial effect on the health care system of the use of NASHA/Dx and SNS. For the scenarios evaluated, when all of the patients receive NASHA/Dx, the net annual effect to the health care payer budget ranged from $571,455 to $2,857,275. When all of the patients receive SNS, the net annual effect to the health care payer budget ranged from $1,959,323 to $9,796,613. Both NASHA/Dx and SNS have produced significant improvements in FI symptoms for affected patients. NASHA/Dx is a cost-effective and more efficient use of resources for the treatment of FI when compared with SNS. The budget impact analysis suggests that although reimbursement for NASHA/Dx treatment initially adds costs to the health care system, it is significantly less expensive than SNS for patients who are candidates for either treatment. Copyright © 2014 The Authors. Published by EM Inc USA.. All rights reserved.

Enhanced cyclic stability of SnS microplates with conformal carbon coating derived from ethanol vapor deposition for sodium-ion batteries

NASA Astrophysics Data System (ADS)

Li, Xiang; Liu, Jiangwen; Ouyang, Liuzhang; Yuan, Bin; Yang, Lichun; Zhu, Min

2018-04-01

Carbon coated SnS microplates (SnS@C MPs) were prepared via a facile chemical vapor deposition method using SnS2 nanoflakes as precursor and ethanol vapor as carbon source. The carbon coating restrains the growth of SnS during the heat treatment. Furthermore, it improves the electronic conductivity as well as accommodates volume variations of SnS during the sodiation and desodiation processes. Therefore, the rate capability and cycle performance of the SnS@C MPs as anode materials for sodium-ion batteries are remarkably enhanced compared with the bare SnS and the SnS2 precursor. At current densities of 0.1, 0.2, 0.5, 1 and 2 A g-1, the optimized SnS@C MPs exhibit stable capacities of 602.9, 532.1, 512.2, 465.9 and 427.2 mAh g-1, respectively. At 1 A g-1, they show a reversible capacity of 528.8 mAh g-1 in the first cycle, and maintain 444.7 mAh g-1 after 50 cycles, with capacity retention of 84.1%. The carbon coating through chemical vapor deposition using ethanol vapor as carbon sources is green, simple and cost-effective, which shows great promise to improve the reversible Na+ storage of electrode materials.

Online Social Networking and Addiction—A Review of the Psychological Literature

PubMed Central

Kuss, Daria J.; Griffiths, Mark D.

2011-01-01

Social Networking Sites (SNSs) are virtual communities where users can create individual public profiles, interact with real-life friends, and meet other people based on shared interests. They are seen as a ‘global consumer phenomenon’ with an exponential rise in usage within the last few years. Anecdotal case study evidence suggests that ‘addiction’ to social networks on the Internet may be a potential mental health problem for some users. However, the contemporary scientific literature addressing the addictive qualities of social networks on the Internet is scarce. Therefore, this literature review is intended to provide empirical and conceptual insight into the emerging phenomenon of addiction to SNSs by: (1) outlining SNS usage patterns, (2) examining motivations for SNS usage, (3) examining personalities of SNS users, (4) examining negative consequences of SNS usage, (5) exploring potential SNS addiction, and (6) exploring SNS addiction specificity and comorbidity. The findings indicate that SNSs are predominantly used for social purposes, mostly related to the maintenance of established offline networks. Moreover, extraverts appear to use social networking sites for social enhancement, whereas introverts use it for social compensation, each of which appears to be related to greater usage, as does low conscientiousness and high narcissism. Negative correlates of SNS usage include the decrease in real life social community participation and academic achievement, as well as relationship problems, each of which may be indicative of potential addiction. PMID:22016701

[Sincerity of effort: isokinetic evaluation of knee extension].

PubMed

Colombo, R; Demaiti, G; Sartorio, F; Orlandini, D; Vercelli, S; Ferriero, G

2008-01-01

The aim of this study was to find a reliable method to evaluate the sincerity of the muscular maximal effort performed in a dynamometric isokinetic test of knee flexion-extension. The coefficient of variation of the peak torque (CV) and 3 new indices were analysed: (1) the average coefficient of variation calculated on the complete peak torque curve (CVM); (2) the slope of the regression line in an endurance test (PRR); (3) the correlation coefficient of the peak torques in the same endurance test (CCR). Twenty healthy subjects underwent assessment in two different trials, maximal (MX) and 50% submaximal (SMX), with 20 minutes of rest between trials. Each trial consisted of 4 tests, each of 3 repetitions, at angular speed of 30, 180, 30, and 180 degrees/s, respectively, and 1 test of 15 repetitions at 240 degrees/s. Our findings confirmed the ability of CV to detect a high percentage of sincere efforts: at 30 degrees/s Sensibility (Sns)=100% and Specificity (Spc)=70%; at 180 degrees/s Sns=75%, Spc=95%. The 3 new indices here proposed showed high characteristics of Sns and Spc, generally better than those of CV. CVM showed at 180 degrees/s Sns=90% and Spc=100%, while at 30 degrees/s Sns=90%, Spc=75%. PRR was the best index identifying all the efforts, except one (Sns=100%, Spc=95%). The CCR coefficient showed Sns and Spc values both of 90%.

Online social networking and addiction--a review of the psychological literature.

PubMed

Kuss, Daria J; Griffiths, Mark D

2011-09-01

Social Networking Sites (SNSs) are virtual communities where users can create individual public profiles, interact with real-life friends, and meet other people based on shared interests. They are seen as a 'global consumer phenomenon' with an exponential rise in usage within the last few years. Anecdotal case study evidence suggests that 'addiction' to social networks on the Internet may be a potential mental health problem for some users. However, the contemporary scientific literature addressing the addictive qualities of social networks on the Internet is scarce. Therefore, this literature review is intended to provide empirical and conceptual insight into the emerging phenomenon of addiction to SNSs by: (1) outlining SNS usage patterns, (2) examining motivations for SNS usage, (3) examining personalities of SNS users, (4) examining negative consequences of SNS usage, (5) exploring potential SNS addiction, and (6) exploring SNS addiction specificity and comorbidity. The findings indicate that SNSs are predominantly used for social purposes, mostly related to the maintenance of established offline networks. Moreover, extraverts appear to use social networking sites for social enhancement, whereas introverts use it for social compensation, each of which appears to be related to greater usage, as does low conscientiousness and high narcissism. Negative correlates of SNS usage include the decrease in real life social community participation and academic achievement, as well as relationship problems, each of which may be indicative of potential addiction.

Social Media in Health Professional Education: A Student Perspective on User Levels and Prospective Applications

ERIC Educational Resources Information Center

Maloney, Stephen; Moss, Alan; Ilic, Dragan

2014-01-01

Social Networking Sites (SNS) have seen exponential growth in recent years. The high utilisation of SNS by tertiary students makes them an attractive tool for educational institutions. This study aims to identify health professional students' use and behaviours with SNS, including students' perspectives on potential applications within…

Enhancing the Performance of Perovskite Solar Cells by Hybridizing SnS Quantum Dots with CH3 NH3 PbI3.

PubMed

Han, Jianhua; Yin, Xuewen; Nan, Hui; Zhou, Yu; Yao, Zhibo; Li, Jianbao; Oron, Dan; Lin, Hong

2017-08-01

The combination of perovskite solar cells and quantum dot solar cells has significant potential due to the complementary nature of the two constituent materials. In this study, solar cells (SCs) with a hybrid CH 3 NH 3 PbI 3 /SnS quantum dots (QDs) absorber layer are fabricated by a facile and universal in situ crystallization method, enabling easy embedding of the QDs in perovskite layer. Compared with SCs based on CH 3 NH 3 PbI 3 , SCs using CH 3 NH 3 PbI 3 /SnS QDs hybrid films as absorber achieves a 25% enhancement in efficiency, giving rise to an efficiency of 16.8%. The performance improvement can be attributed to the improved crystallinity of the absorber, enhanced photo-induced carriers' separation and transport within the absorber layer, and improved incident light utilization. The generality of the methods used in this work paves a universal pathway for preparing other perovskite/QDs hybrid materials and the synthesis of entire nontoxic perovskite/QDs hybrid structure. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Flexible low-cost infrared photodetector based on SnS thin film grown by chemical bath deposition

NASA Astrophysics Data System (ADS)

Mahdi, Mohamed S.; Ibrahim, K.; Ahmed, Naser M.; Kadhim, A.; Azzez, Shrook A.; Mustafa, Falah I.; Bououdina, M.

2017-10-01

A novel, flexible, and low-cost infrared (IR) SnS photodetector was fabricated onto a polyethylene terephthalate (PET) substrate by a simple approach based on chemical bath deposition. X-ray diffraction analysis confirmed an orthorhombic structure, scanning electron microscopy observations revealed flower-like morphology, and UV-vis spectroscopy indicated a direct energy gap of 1.42 eV. The photodetector exhibited maximum responsivity at 850 nm under the illumination of a Hg (Xe) lamp. The photoresponse properties of the photodetector were determined under illumination of 850 nm at various bias voltages (3, 5 and 7 V). The photodetector manifested good sensitivity, excellent reproducibility and fast response time. Both rise/decay times measured at bias voltage of 3 V were determined: τ rise  =  0.38 s and τ decay  =  0.67 s. Additionally, the photoresponse versus different power density of illumination was also measured. The as-obtained results, highlighted that the newly fabricated SnS photodetector can be considered as a promising photoelectronic device that can be effectively used in the IR region due to its excellent photoresponce characteristics, low cost, flexibility, and non-toxicity.

Open chromatin structures regulate the efficiencies of pre-RC formation and replication initiation in Epstein-Barr virus

PubMed Central

Papior, Peer; Arteaga-Salas, José M.; Günther, Thomas; Grundhoff, Adam

2012-01-01

Whether or not metazoan replication initiates at random or specific but flexible sites is an unsolved question. The lack of sequence specificity in origin recognition complex (ORC) DNA binding complicates genome-scale chromatin immunoprecipitation (ChIP)-based studies. Epstein-Barr virus (EBV) persists as chromatinized minichromosomes that are replicated by the host replication machinery. We used EBV to investigate the link between zones of pre-replication complex (pre-RC) assembly, replication initiation, and micrococcal nuclease (MNase) sensitivity at different cell cycle stages in a genome-wide fashion. The dyad symmetry element (DS) of EBV’s latent origin, a well-established and very efficient pre-RC assembly region, served as an internal control. We identified 64 pre-RC zones that correlate spatially with 57 short nascent strand (SNS) zones. MNase experiments revealed that pre-RC and SNS zones were linked to regions of increased MNase sensitivity, which is a marker of origin strength. Interestingly, although spatially correlated, pre-RC and SNS zones were characterized by different features. We propose that pre-RCs are formed at flexible but distinct sites, from which only a few are activated per single genome and cell cycle. PMID:22891264

First-principles study of SnS electronic properties using LDA, PBE and HSE06 functionals

NASA Astrophysics Data System (ADS)

Ibragimova, R.; Ganchenkova, M.; Karazhanov, S.; Marstein, E. S.

2018-03-01

Recently, tin sulphide (SnS) has emerged as a promising alternative to conventional CIGS and CZTC for use in solar cells, possessing such properties as non-toxicity, low cost and production stability. SnS has a high theoretically predicted efficiency above 20%, but the experimentally achieved efficiency so far is as low as 4.36%. The reason for the low achieved efficiency is unclear. One of the powerful tools to get deeper insights about the nature of the problem is first-principles calculation approaches. That is why SnS has become an attractive subject for first-principles calculations recently. Previously calculated data, however, show a widespread of such fundamental value as the bandgap varying from 0.26 to 1.26 eV. In order to understand a reason for that, in this work, we concentrate on a systematic study of calculation parameters effects on the resulting electronic structure, with the particular attention paid to the influence of the exchange-correlation functional chosen for calculations. Several exchange-correlation functionals (LDA, PBE and HSE06) were considered. The systematic analysis has shown that the bandgap variation can result from a tensile/compressive hydrostatic pressure introduced by non-equilibrium lattice parameters used for the calculations. The study of the applicability of three functionals has shown that HSE06 gives the best match to both experimentally obtained bandgap and the XPS valence band spectra. LDA underestimates the bandgap but qualitatively reproduces experimentally measured valence DOS similar to that of HSE06 in contrast to PBE. PBE underestimates the bandgap and does not match to the measured XPS spectra.

Long term safety of sacral nerve modulation in medicare beneficiaries.

PubMed

Chughtai, Bilal; Sedrakyan, Art; Isaacs, Abby; Lee, Richard; Te, Alexis; Kaplan, Steven

2015-09-01

Sacral nerve stimulation (SNS) is FDA approved as second-line therapy for both urinary and bowel control. However, there is limited evidence regarding long term safety. We determined adverse events associated with SNS among Medicare beneficiaries. We used the 5% national random sample of Medicare claims for 2001-2011 to identify patients. Patients who underwent SNS implantation were identified with Current Procedure Terminology (CPT-4) codes. We determined safety of SNS using analysis of complication occurrences on day of surgery and during 5 years following initial procedure. SAS v9.3 statistical package was used. One thousand four hundred seventy-four patients underwent treatment with SNS in the 5% national sample of Medicare patients within the time period. Representative of real-world patients undergoing SNS surgery, comorbidities included hypertension (69.3%), diabetes (29.4%), chronic pulmonary disease (25.5%), hypothyroidism (25.2%), and depression (22.7%). Few complications occurred on day of surgery. At 90 days, 3.2% of patients had bowel complications, 2.0% urological, 9.4% infectious, and 1.5% stroke. Overall, bowel, neurological health event occurrences were consistent with prior year rates, while infectious events decreased. Of 206 patients who were followed for at least 5 years, 17.3% had devices removed and 11.3% replaced, with 26.1% having at least one of those, leaving 73.9% with original devices. Urological, infectious, and bowel complication occurrences were low after SNS among Medicare beneficiaries with multiple comorbidities. There were infrequent serious complications like hemorrhage and stroke postoperatively. Although SNS appears safe in this high-risk population, a comprehensive registry will ensure continuous safety. © 2014 Wiley Periodicals, Inc.

Investigation of user behavior on social networking sites

PubMed Central

2017-01-01

Social networking sites (SNS) are used for social and professional interaction with people. SNS popularity has encouraged researchers to analyze the relationship of activities performed on SNS with user behavior. In doing so, the term “user behavior” is rather used ambiguously with different interpretations, which makes it difficult to identify studies on user behavior in relation to SNS. This phenomenon has encouraged this thorough research on the characteristics of user behavior being discussed in the literature. Therefore, in this study, we aim to identify, analyze, and classify the characteristics associated with user behavior to answer the research questions designed to conduct this research. A mapping study (also called scoping study), which is a type of systematic literature review, is employed to identify potential studies from digital databases through a developed protocol. Thematic analysis is carried out for the classification of user behavior. We identified 116 primary studies for full analysis. This study found seven characteristics associated with behavior that have direct influence on SNS use and nine factors that have an indirect effect. All studies were conducted largely under seven areas that set the context of these studies. Findings show that the research on SNS is still in its early stage. The range of topics covered in the analyzed studies is quite expansive, although the depth in terms of number of studies under each topic is quite limited. This study reports that activities performed on SNS are either associated with user behavior or reflect personality characteristics. The findings of this study could be used by practitioners to evaluate their SNS platforms and develop more user-centered applications. These studies can also help organizations to understand better the needs of their employees. PMID:28151963

Investigation of user behavior on social networking sites.

PubMed

Waheed, Hajra; Anjum, Maria; Rehman, Mariam; Khawaja, Amina

2017-01-01

Social networking sites (SNS) are used for social and professional interaction with people. SNS popularity has encouraged researchers to analyze the relationship of activities performed on SNS with user behavior. In doing so, the term "user behavior" is rather used ambiguously with different interpretations, which makes it difficult to identify studies on user behavior in relation to SNS. This phenomenon has encouraged this thorough research on the characteristics of user behavior being discussed in the literature. Therefore, in this study, we aim to identify, analyze, and classify the characteristics associated with user behavior to answer the research questions designed to conduct this research. A mapping study (also called scoping study), which is a type of systematic literature review, is employed to identify potential studies from digital databases through a developed protocol. Thematic analysis is carried out for the classification of user behavior. We identified 116 primary studies for full analysis. This study found seven characteristics associated with behavior that have direct influence on SNS use and nine factors that have an indirect effect. All studies were conducted largely under seven areas that set the context of these studies. Findings show that the research on SNS is still in its early stage. The range of topics covered in the analyzed studies is quite expansive, although the depth in terms of number of studies under each topic is quite limited. This study reports that activities performed on SNS are either associated with user behavior or reflect personality characteristics. The findings of this study could be used by practitioners to evaluate their SNS platforms and develop more user-centered applications. These studies can also help organizations to understand better the needs of their employees.

Social networking sites (SNS); exploring their uses and associated value for adolescent mothers in Western Australia in terms of social support provision and building social capital.

PubMed

Nolan, Samantha; Hendricks, Joyce; Towell, Amanda

2015-09-01

to explore the use of social networking sites (SNS) by adolescent mothers in Western Australia (WA) in relation to social support and the building of social capital. a constructionist narrative inquiry approach was employed to guide the research design and processes. Approval was gained from the university human ethics department. Sampling was purposeful and data were collected using in-depth interviews with seven adolescent mothers in WA. interviews were undertaken within the homes of adolescent mothers across WA. from within three fundamental domains of social support; tangible, emotional and informational support, provided by SNS use, five key themes were identified from the narratives. 'Social connectedness' was identified as a form of tangible support, sometimes termed 'practical' or 'instrumental' support. This theme incorporates connectedness with family, friends, and peers and across new and existing social groups. Three themes were identified that relate to emotional support; 'increased parenting confidence'; 'reduced parental stress' and 'enhanced self-disclosure' afforded by use of SNS. 'Access to information' was identified in terms of informational support, with participants often highlighting SNS use as their primary portal for information and advice. the findings of this study suggest that SNS use affords adolescent mothers in WA access to tangible, informational and emotional support and thus is a valuable source of social capital for these mothers. This study provides a platform for further exploration into this phenomenon, and possible implications include the potential for midwives and health care professionals to promote the benefits of SNS use with, and for, this group of mothers, or to incorporate SNS use into modern health care practices to further develop the potential for improved social capital related outcomes for them. Copyright © 2015 Elsevier Ltd. All rights reserved.

Giant piezoelectricity of monolayer group IV monochalcogenides: SnSe, SnS, GeSe, and GeS

NASA Astrophysics Data System (ADS)

Fei, Ruixiang; Li, Wenbin; Li, Ju; Yang, Li

2015-10-01

We predict enormous, anisotropic piezoelectric effects in intrinsic monolayer group IV monochalcogenides (MX, M=Sn or Ge, X=Se or S), including SnSe, SnS, GeSe, and GeS. Using first-principle simulations based on the modern theory of polarization, we find that their piezoelectric coefficients are about one to two orders of magnitude larger than those of other 2D materials, such as MoS2 and GaSe, and bulk quartz and AlN which are widely used in industry. This enhancement is a result of the unique "puckered" C2v symmetry and electronic structure of monolayer group IV monochalcogenides. Given the achieved experimental advances in the fabrication of monolayers, their flexible character, and ability to withstand enormous strain, these 2D structures with giant piezoelectric effects may be promising for a broad range of applications such as nano-sized sensors, piezotronics, and energy harvesting in portable electronic devices.

Schottky barrier tuning of the graphene/SnS2 van der Waals heterostructures through electric field

NASA Astrophysics Data System (ADS)

Zhang, Fang; Li, Wei; Ma, Yaqiang; Dai, Xianqi

2018-03-01

Combining the electronic structures of two-dimensional monolayers in ultrathin hybrid nanocomposites is expected to display new properties beyond their single components. The effects of external electric field (Eext) on the electronic structures of monolayer SnS2 with graphene hybrid heterobilayers are studied by using the first-principle calculations. It is demonstrated that the intrinsic electronic properties of SnS2 and graphene are quite well preserved due to the weak van der Waals (vdW) interactions. We find that the n-type Schottky contacts with the significantly small Schottky barrier are formed at the graphene/SnS2 interface. In the graphene/SnS2 heterostructure, the vertical Eext can control not only the Schottky barriers (n-type and p-type) but also contact types (Schottky contact or Ohmic contact) at the interface. The present study would open a new avenue for application of ultrathin graphene/SnS2 heterostructures in future nano- and optoelectronics.

Taking Stress Response out of the Box: Stability, Discontinuity, and Temperament Effects on HPA and SNS across Social Stressors in Mother-Infant Dyads

ERIC Educational Resources Information Center

Laurent, Heidemarie K.; Ablow, Jennifer C.; Measelle, Jeffrey

2012-01-01

This study investigated continuity and stability of hypothalamic-pituitary-adrenal (HPA) and sympathetic nervous system (SNS) response measures in mother-infant dyads across 2 different types of social stress sessions. Synchrony of response trajectories across systems (SNS-HPA coordination) and partners (mother-infant attunement) was addressed, as…

Tracking Stripped Proton Particles in SNS Ring Injection Momentum Dump Line

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Jian-Guang

3D computer simulations are performed to study magnetic field distributions and particle trajectories along the SNS ring injection momentum dump line. Optical properties and transfer maps along the dump line are calculated. The stripped proton particle distributions on the dump window are analyzed. The study has provided useful information for the redesign of the SNS ring injection beam dump.

SNS Heterojunctions With New Combinations Of Materials

NASA Technical Reports Server (NTRS)

Vasquez, Richard P.; Hunt, Brian D.; Foote, Marc C.

1992-01-01

New combinations of materials proposed for superconductor/normal-metal/superconductor (SNS) heterojunctions in low-temperature electronic devices such as fast switches, magnetometers, and mixers. Epitaxial heterojunctions formed between high-temperature superconductors and either oxide semiconductors or metals. Concept offers alternative to other three-layer heterojunction concepts; physical principles of operation permit SNS devices to have thicker barrier layers and fabricated more easily.

A Personal Statement about a Four-Year Curriculum for Heritage and Native Speakers of Spanish Programs.

ERIC Educational Resources Information Center

Stering, Edward

This document shares a vision for a 4-year curriculum for Heritage Speakers of Spanish (HSS)/Spanish for Native Speakers (SNS), describing a course developed for SNS students within Mercy High School in San Francisco, California. The vision foresees an ever-increasing number of HSS and SNS students completing college level degree programs then…

Exploring the Usefulness of School Education about Risks on Social Network Sites: A Survey Study

ERIC Educational Resources Information Center

Vanderhoven, Ellen; Schellens, Tammy; Valcke, Martin

2013-01-01

The growing popularity of social network sites (SNS) is causing concerns about privacy and security, especially with teenagers, since they show various forms of unsafe behavior on SNS. It has been put forth by researchers, teachers, parents, and teenagers that school is ideally placed to educate teens about risks on SNS and to teach youngsters how…

Shadow netWorkspace: An Open Source Intranet for Learning Communities

ERIC Educational Resources Information Center

Laffey, James M.; Musser, Dale

2006-01-01

Shadow netWorkspace (SNS) is a web application system that allows a school or any type of community to establish an intranet with network workspaces for all members and groups. The goal of SNS has been to make it easy for schools and other educational organizations to provide network services in support of implementing a learning community. SNS is…

Activities in Cu2S-FeS-SnS melts at 1200 °C

NASA Astrophysics Data System (ADS)

Eric, R. Hurman

1993-04-01

The dew-point technique was used to measure the vapor pressures of SnS over liquid sulfides of the system Cu2S-FeS-SnS at 1200 °C. Activities of SnS were generated from the measured vapor pressures of SnS. Activities of Cu2S and FeS were evaluated both in binary and ternary melts by Gibbs-Duhem calculations from the known SnS activity data. The systems Cu2S-SnS and Cu2S-FeS exhibit negative departures from ideal behavior, while FeS-SnS melts exhibit positive deviations.

The absorption, distribution, excretion and toxicity of mesoporous silica nanoparticles in mice following different exposure routes.

PubMed

Fu, Changhui; Liu, Tianlong; Li, Linlin; Liu, Huiyu; Chen, Dong; Tang, Fangqiong

2013-03-01

Mesoporous silica nanoparticles (MSNs) are emerging as one of the promising nanomaterials for biomedical applications, but the nanomaterials-body interaction exposed by different administration routes remained poorly understood. In the present study, a systematic investigation of the absorption, distribution, excretion and toxicity of silica nanoparticles (SNs) with the average size of 110 nm after four different exposure routes including intravenous, hypodermic, intramuscular injection and oral administration to mice were achieved. The results showed that a fraction of the SNs administrated by the intramuscular and hypodermic injection could cross different biological barriers into the liver but with a low absorption rate. Exposing by oral administration, SNs were absorbed into the intestinal tract and persisted in the liver. And SNs administrated by intravenous injection were mainly present in the liver and spleen. In addition, SNs could cause inflammatory response around the injection sites after intramuscular and hypodermic injection. It was also found that SNs were mainly excreted through urine and feces after different exposure routes. This study will be helpful for selecting the appropriate exposed routes for the development of nanomaterials-based drug delivery system for biomedical applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

Hemispheric Sunspot Unit Area: Comparison with Hemispheric Sunspot Number and Sunspot Area

NASA Astrophysics Data System (ADS)

Li, K. J.; Xiang, N. B.; Qu, Z. N.; Xie, J. L.

2014-03-01

The monthly mean northern and southern hemispheric sunspot numbers (SNs) and sunspot areas (SAs) in the time interval of 1945 January to 2012 December are utilized to construct the monthly northern and southern hemispheric sunspot unit areas (SUAs), which are defined as the ratio of hemispheric SA to SN. Hemispheric SUAs are usually found to rise at the beginning and to fall at the ending time of a solar cycle more rapidly, forming a more irregular cycle profile than hemispheric SNs and SAs, although it also presents Schwabe-cycle-like hemispheric SNs and SAs. Sunspot activity (SN, SA, and SUA) is found asynchronously and is asymmetrically distributed in the northern and southern hemispheres, and hemispheric SNs, SAs, and SUAs are not in phase in the two hemispheres. The similarity of hemispheric SNs and SAs is found to be much more obvious than that of hemispheric SUAs and SNs (or SAs), and also for their north-south asymmetry. A notable feature is found for the behavior of the SUA around the minimum time of cycle 24: the SUA rapidly decreases from the cycle maximum value to the cycle minimum value of sunspot cycles 19-24 within just 22 months.

Hemispheric sunspot unit area: comparison with hemispheric sunspot number and sunspot area

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, K. J.; Xiang, N. B.; Qu, Z. N.

2014-03-01

The monthly mean northern and southern hemispheric sunspot numbers (SNs) and sunspot areas (SAs) in the time interval of 1945 January to 2012 December are utilized to construct the monthly northern and southern hemispheric sunspot unit areas (SUAs), which are defined as the ratio of hemispheric SA to SN. Hemispheric SUAs are usually found to rise at the beginning and to fall at the ending time of a solar cycle more rapidly, forming a more irregular cycle profile than hemispheric SNs and SAs, although it also presents Schwabe-cycle-like hemispheric SNs and SAs. Sunspot activity (SN, SA, and SUA) is foundmore » asynchronously and is asymmetrically distributed in the northern and southern hemispheres, and hemispheric SNs, SAs, and SUAs are not in phase in the two hemispheres. The similarity of hemispheric SNs and SAs is found to be much more obvious than that of hemispheric SUAs and SNs (or SAs), and also for their north-south asymmetry. A notable feature is found for the behavior of the SUA around the minimum time of cycle 24: the SUA rapidly decreases from the cycle maximum value to the cycle minimum value of sunspot cycles 19-24 within just 22 months.« less

Segregation of chlorine in n-type tin monosulfide ceramics: Actual chlorine concentration for carrier-type conversion

NASA Astrophysics Data System (ADS)

Iguchi, Yuki; Sugiyama, Taiki; Inoue, Kazutoshi; Yanagi, Hiroshi

2018-05-01

Tin monosulfide (SnS) is an attractive material for photovoltaic cells because of its suitable band-gap energy, high absorption coefficient, and non-toxic and abundant constituent elements. The primary drawback of this material is the lack of n-type SnS. We recently demonstrated n-type SnS by doping with Cl. However, the Cl-doped n-type SnS bulk ceramics exhibited an odd behavior in which carrier-type conversion but not electron carrier concentration depended on the Cl concentration. In this study, the electron probe microanalysis (EPMA) elemental mapping of Cl-doped SnS revealed continuous homogeneous regions with a relatively low Cl concentration along with the islands of high Cl concentration in which Sn/S is far from unity. The difference between the Cl concentration in the homogeneous region (determined by EPMA) and the bulk Cl concentration (determined by wavelength-dispersive X-ray fluorescence spectroscopy) increased with the increasing Cl doping amount. The carrier concentration and the Hall coefficient clearly depended on the Cl concentration in the homogeneous region. Carrier-type conversion was observed at the Cl concentration of 0.26 at. % (in the homogeneous region).

Analysis of SnS2 hyperdoped with V proposed as efficient absorber material.

PubMed

Seminovski, Yohanna; Palacios, Pablo; Wahnón, Perla

2014-10-01

Intermediate-band materials can improve the photovoltaic efficiency of solar cells through the absorption of two subband-gap photons that allow extra electron-hole pair formations. Previous theoretical and experimental findings support the proposal that the layered SnS2 compound, with a band-gap of around 2 eV, is a candidate for an intermediate-band material when it is doped with a specific transition-metal. In this work we characterize vanadium doped SnS2 using density functional theory at the dilution level experimentally found and including a dispersion correction combined with the site-occupancy-disorder method. In order to analyze the electronic characteristics that depend on geometry, two SnS2 polytypes partially substituted with vanadium in symmetry-adapted non-equivalent configurations were studied. In addition the magnetic configurations of vanadium in a SnS2 2H-polytype and its comparison with a 4H-polytype were also characterized. We demonstrate that a narrow intermediate-band is formed, when these dopant atoms are located in different layers. Our theoretical predictions confirm the recent experimental findings in which a paramagnetic intermediate-band material in a SnS2 2H-polytype with 10% vanadium concentration is obtained.

Social Network Sites as a Mode to Collect Health Data: A Systematic Review

PubMed Central

Ramzan, Farzan; Rawaf, Salman; Majeed, Azeem

2014-01-01

Background To date, health research literature has focused on social network sites (SNS) either as tools to deliver health care, to study the effect of these networks on behavior, or to analyze Web health content. Less is known about the effectiveness of these sites as a method for collecting data for health research and the means to use such powerful tools in health research. Objective The objective of this study was to systematically review the available literature and explore the use of SNS as a mode of collecting data for health research. The review aims to answer four questions: Does health research employ SNS as method for collecting data? Is data quality affected by the mode of data collection? What types of participants were reached by SNS? What are the strengths and limitations of SNS? Methods The literature was reviewed systematically in March 2013 by searching the databases MEDLINE, Embase, and PsycINFO, using the Ovid and PubMed interface from 1996 to the third week of March 2013. The search results were examined by 2 reviewers, and exclusion, inclusion, and quality assessment were carried out based on a pre-set protocol. Results The inclusion criteria were met by 10 studies and results were analyzed descriptively to answer the review questions. There were four main results. (1) SNS have been used as a data collection tool by health researchers; all but 1 of the included studies were cross-sectional and quantitative. (2) Data quality indicators that were reported include response rate, cost, timeliness, missing data/completion rate, and validity. However, comparison was carried out only for response rate and cost as it was unclear how other reported indicators were measured. (3) The most targeted population were females and younger people. (4) All studies stated that SNS is an effective recruitment method but that it may introduce a sampling bias. Conclusions SNS has a role in health research, but we need to ascertain how to use it effectively without affecting the quality of research. The field of SNS is growing rapidly, and it is necessary to take advantage of the strengths of this tool and to avoid its limitations by effective research design. This review provides an important insight for scholars who plan to conduct research using SNS. PMID:25048247

Tin Sulfide Phase Exploration: Dependence of Optoelectronic Properties on Microstructural Growth and Chemical Variations in Thin Film Material

NASA Astrophysics Data System (ADS)

Banai, Rona Elinor

Herzenbergite tin (II) monosulfide (alpha-SnS) is of growing interest as a photovoltaic material because of its interesting optoelectronic properties and Earth abundance. It has several stable phases due to the dual valency of tin. As a layered material, alpha-SnS has the ability to form varying microstructure with differing properties. For this dissertation, films were RF sputtered from a SnS and SnS2 target to produce films with varying microstructure. Growth of high energy phases includin beta-SnS and amorphous SnS2 were possible through sputtering. Films of mixed or strained phase resulted from both targets. Pure phase alpha-SnS was made by annealing amorphous SnS2 films. Microstructure was measured using grazing incidence XRD and field emission SEM. The impact of microstructure was seen for both optical and electronic properties. Films were evaluated using spectroscopic ellipsometry as well as unpolarized UV-Vis transmission and reflection measurements. Optical modeling of the films is sufficient for developing models corresponding to specific microstructure, enabling it to be an inexpensive tool for studying the material. Absorption coefficient and band gap were also derived for these films. Films deposited with the SnS target had resistivity values up to 20,000 O-cm. Annealing of amorphous films deposited from the SnS2 target resulted in alpha-SnS films with much lower resistivity (<50 O-cm) values. This method for producing alpha-SnS offered better control of the phase, microstructure and therefore optoelectronic properties. While SnS films made from either target were typically p-type, sputtering of the SnS2 target with substrate heating resulted in n-type SnSx of a potentially new phase similar to SnS2 but with a 2:3 tin-to-sulfur ratio. Resistivity of those films typically ranged from 1 to 40 O-cm. Both p- and n-type films made from the SnS2 target had high carrier concentration of 10 17 to 1020 cm-3, but films had low Hall mobility such that conductivity type was not determined. Titanium, molybdenum, and aluminum contacts were tested for Ohmic and Schottky behavior using transmission line measurements. The complexity of its microstructure and flexibility in formation of varying phase and altered phase presents challenges to its use as a PV absorber.

Laparoscopic sentinel lymph node procedure using a combination of patent blue and radioisotope in women with cervical carcinoma.

PubMed

Barranger, Emmanuel; Grahek, Dany; Cortez, Annie; Talbot, Jean Noel; Uzan, Serge; Darai, Emile

2003-06-15

The authors evaluated the feasibility of a laparoscopic sentinel lymph node (SN) procedure with combined radioisotopic and patent blue labeling in patients with cervical carcinoma. Thirteen women (median age, 52.5 years) with cervical carcinoma (Stage Ia2 in 1 patient, Stage Ib1 in 10 patients, Stage Ib2 in 1 patient, and Stage IIa in 1 patient) underwent a laparoscopic SN procedure using an endoscopic gamma probe after both radioactive isotope and patent blue injections. After the procedure, all patients underwent complete laparoscopic pelvic lymphadenectomy and either laparoscopic radical hysterectomy (eight patients) or the Schauta-Amreich operation (five patients). SNs (mean, 1.7 SNs per patient; range, 1-3 SNs per patient) were identified in 12 of 13 patients. A median of 10.5 pelvic lymph nodes per patient (range, 4-17 pelvic lymph nodes per patient) were removed. No lymph node involvement was detected in SNs with hematoxylin and eosin staining. Immunohistochemical studies identified four metastatic SNs in two patients, with micrometastases in two SNs from the first patient and isolated tumor cells in two SNs from the second patient. No false-negative SN results were obtained. The results of this study suggest that SN detection with a combination of radiocolloid and patent blue is feasible in patients with cervical carcinoma. The combination of laparoscopy and the SN procedure permitted minimally invasive management of early-stage disease. Copyright 2003 American Cancer Society.

Effect of annealing on physical characteristics of the vacuum evaporated mixed phase Sn x S y thin films

NASA Astrophysics Data System (ADS)

Banotra, A.; Padha, N.

2017-11-01

The mixed phase Sn x S y films of the thickness of 200 nm were obtained by annealing in an indigenously designed furnace at 473 K, 523 K, 573 K and 623 K for 1 h at each temperature. Prior to annealing, the precursor ‘Sn’ and ‘S’ materials were mixed up in a ball milling setup and thermally evaporated at the vacuum pressure ~2  ×  10-6 mbar on corning glass substrate. The increase in the annealing temperature influenced the reaction kinetics of ‘Sn’ and ‘S’ materials and led to the formation of SnS phase at 473 K. The SnS phase existed from 473 K to 573 K and transformed to Sn2S3 at temperatures between 573 K and 623 K. Besides this, the SnS2 phase co-existed in all undertaken temperatures where intensity of its most prominent peak increased with increase in annealing temperature. The transmittance (%) values of the undertaken films increased with increase in the annealing temperature in the wavelengths varying from 400 nm (visible) to 1600 nm (NIR). The absorption coefficient (α) values decreased with increase in annealing temperature from 1  ×  105 to 4  ×  104 cm-1 in the visible region and attained saturation values (~2  ×  104 cm-1) in the NIR region. The films possessed direct bandgap (E g) with values increasing from 1.90 eV to 2.82 eV with increase in the annealing temperature from 473 K to 623 K it also possessed indirect bandgaps with E g values varying from 0.82 eV to 1.52 eV with increase in annealing temperature in the same temperature range. The 473 K annealed samples provided irregular shaped SnS grains indicated by bright crystallites which reached to their stable position with enhanced crystallinity at the annealing temperatures of 523 K and 573 K. The SnS grains, however, reduced to lesser number at 623 K due to growth of Sn2S3 crystallites at the expense of SnS. The ‘S’ rich SnS phase (SnS2) crystallites were seen represented by darker crystallites appeared at 523 K, 573 K and 623 K. The current-voltage (I-V) study of the FTO/Film/Ag structure confirmed the schottky diode formation between Ag and film interface. There are variations in the I-V behaviour of diodes which resulted in random changes in the values of ‘ideality factor’ and ‘barrier heights’. The changes in diode parameters may be due to variation in the interface states, surface defects and barrier inhomogenities occurring due to compositional changes in Sn x S y films.

Effect of direct reciprocity and network structure on continuing prosperity of social networking services.

PubMed

Osaka, Kengo; Toriumi, Fujio; Sugawara, Toshihauru

2017-01-01

Social networking services (SNSs) are widely used as communicative tools for a variety of purposes. SNSs rely on the users' individual activities associated with some cost and effort, and thus it is not known why users voluntarily continue to participate in SNSs. Because the structures of SNSs are similar to that of the public goods (PG) game, some studies have focused on why voluntary activities emerge as an optimal strategy by modifying the PG game. However, their models do not include direct reciprocity between users, even though reciprocity is a key mechanism that evolves and sustains cooperation in human society. We developed an abstract SNS model called the reciprocity rewards and meta-rewards games that include direct reciprocity by extending the existing models. Then, we investigated how direct reciprocity in an SNS facilitates cooperation that corresponds to participation in SNS by posting articles and comments and how the structure of the networks of users exerts an influence on the strategies of users using the reciprocity rewards game. We run reciprocity rewards games on various complex networks and an instance network of Facebook and found that two types of stable cooperation emerged. First, reciprocity slightly improves the rate of cooperation in complete graphs but the improvement is insignificant because of the instability of cooperation. However, this instability can be avoided by making two assumptions: high degree of fun, i.e. articles are read with high probability, and different attitudes to reciprocal and non-reciprocal agents. We then propose the concept of half free riders to explain what strategy sustains cooperation-dominant situations. Second, we indicate that a certain WS network structure affects users' optimal strategy and facilitates stable cooperation without any extra assumptions. We give a detailed analysis of the different characteristics of the two types of cooperation-dominant situations and the effect of the memory of reciprocal agents on cooperation.

Structural studies of ZnO nanostructures by varying the deposition parameters

NASA Astrophysics Data System (ADS)

Yunus, S. H. A.; Sahdan, M. Z.; Ichimura, M.; Supee, A.; Rahim, S.

2017-01-01

The effect of Zinc Oxide (ZnO) thin film on the growth of ZnO nanorods (NRs) was investigated. The structures of ZnO NRs were synthesized by chemical bath deposition (CBD) method in aqueous solution of N2O6Zn.6H2O and C6H12N4 at 90°C of deposition temperature. One of the ZnO NRs samples was deposited on a ZnO seed layer coated on a glass substrate to investigate the properties of ZnO NRs without receiving effect of other materials. Next, for diode application, the ZnO NRs was deposited on tin monosulfide (SnS) coated on indium-tin-oxide (ITO) coated glass substrate (SnS/ITO). The next, the ZnO structural properties were studied from surface morphology, X-ray diffractometer (XRD) spectra, and chemical composition by using field emission scanning electron microscope (FESEM), XRD and energy dispersive X-ray Spectroscopy (EDX). The growth of ZnO NRs on ZnO seed layer was investigated by ZnO seed layer condition while the growth of ZnO NRs on SnS/ITO was investigated by deposition time and deposition temperature parameters. From FESEM images, aligned ZnO NRs were obtained, and the diameters of ZnO NRs were 0.024-3.94 µm. The SnS thin film was affected by the diameter of ZnO NRs which are the ZnO NRs grow on SnS thin films has a larger diameter compared to ZnO NRs grow on ZnO seed layer. Besides that, all of ZnO peaks observed from XRD corresponding to the wurzite structure and preferentially oriented along the c-axis. In addition, EDX shows a high composition of zinc (Zn) and oxygen (O) signals, which indicated that the NRs are indeed made up of Zn and O.

The association between exposure to social media alcohol marketing and youth alcohol use behaviors in India and Australia.

PubMed

Gupta, Himanshu; Lam, Tina; Pettigrew, Simone; Tait, Robert J

2018-06-13

Alcohol marketing on social networking sites (SNS) is associated with alcohol use among young people. Alcohol companies adapt their online marketing content to specific national contexts and responses to such content differ by national settings. However, there exists very little academic work comparing the association between alcohol marketing on SNS and alcohol use among young people in different national settings and across different SNS. Therefore, we aimed to extend the limited existing work by investigating and comparing the association between self-reported exposure to alcohol marketing on three leading SNS (Facebook, YouTube, and Twitter) and alcohol use among young people in diverse national contexts (India and Australia). Cross-sectional, self-report data were obtained from a convenience sample of 631 respondents (330 in India; 301 in Australia) aged 13-25 years via online surveys. Respondents answered questions on their drinking behaviors and involvement with alcohol marketing on SNS. Many respondents from both countries reported interacting with alcohol content online, predominantly on Facebook, followed by YouTube and then Twitter. The interaction was primarily in the forms of posting/liking/sharing/commenting on items posted on alcohol companies' social media accounts, viewing the event page/attending the event advertised by an alcohol company via social media, and/or accessing an alcohol website. Multivariate analyses demonstrated significant associations between respondents' interaction with alcohol content and drinking levels, with effects differing by SNS, demographic group, and country. For example, having friends who shared alcohol-related content was an important predictor of usual alcohol consumption for Indian respondents (p < .001), whereas posting alcohol-related information themselves was a stronger predictor among Australians (p < .001). The results suggest that interaction with alcohol-related content on SNS is associated with young people's alcohol use behaviors and that these behaviors vary by national settings. This study extends previous work by demonstrating this connection across varying social media platforms and national contexts. The results highlight the need to formulate and implement strategies to effectively regulate the SNS alcohol marketing, especially among younger SNS users.

Overview of ten-year operation of the superconducting linear accelerator at the Spallation Neutron Source

NASA Astrophysics Data System (ADS)

Kim, S.-H.; Afanador, R.; Barnhart, D. L.; Crofford, M.; Degraff, B. D.; Doleans, M.; Galambos, J.; Gold, S. W.; Howell, M. P.; Mammosser, J.; McMahan, C. J.; Neustadt, T. S.; Peters, C.; Saunders, J. W.; Strong, W. H.; Vandygriff, D. J.; Vandygriff, D. M.

2017-04-01

The Spallation Neutron Source (SNS) has acquired extensive operational experience of a pulsed proton superconducting linear accelerator (SCL) as a user facility. Numerous lessons have been learned in its first 10 years operation to achieve a stable and reliable operation of the SCL. In this paper, an overview of the SNS SCL design, qualification of superconducting radio frequency (SRF) cavities and ancillary subsystems, an overview of the SNS cryogenic system, the SCL operation including SCL output energy history and downtime statistics, performance stability of the SRF cavities, efforts for SRF cavity performance recovery and improvement at the SNS, and maintenance activities for cryomodules are introduced.

Overview of ten-year operation of the superconducting linear accelerator at the Spallation Neutron Source

DOE PAGES

Kim, Sang-Ho; Afanador, Ralph; Barnhart, Debra L.; ...

2017-02-04

The Spallation Neutron Source (SNS) has acquired extensive operational experience of a pulsed proton superconducting linear accelerator (SCL) as a user facility. Numerous lessons have been learned in its first 10 years operation to achieve a stable and reliable operation of the SCL. In this paper, an overview of the SNS SCL design, qualification of superconducting radio frequency (SRF) cavities and ancillary subsystems, an overview of the SNS cryogenic system, the SCL operation including SCL output energy history and downtime statistics, performance stability of the SRF cavities, efforts for SRF cavity performance recovery and improvement at the SNS, and maintenancemore » activities for cryomodules are introduced.« less

Overview of ten-year operation of the superconducting linear accelerator at the Spallation Neutron Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Sang-Ho; Afanador, Ralph; Barnhart, Debra L.

The Spallation Neutron Source (SNS) has acquired extensive operational experience of a pulsed proton superconducting linear accelerator (SCL) as a user facility. Numerous lessons have been learned in its first 10 years operation to achieve a stable and reliable operation of the SCL. In this paper, an overview of the SNS SCL design, qualification of superconducting radio frequency (SRF) cavities and ancillary subsystems, an overview of the SNS cryogenic system, the SCL operation including SCL output energy history and downtime statistics, performance stability of the SRF cavities, efforts for SRF cavity performance recovery and improvement at the SNS, and maintenancemore » activities for cryomodules are introduced.« less

Damping the e-p instability in the SNS accumulator ring

NASA Astrophysics Data System (ADS)

Evans, N. J.; Deibele, C.; Aleksandrov, A.; Xie, Z.

2018-03-01

A broadband, digital damper system for both transverse planes developed for the SNS accumulator ring has recently damped the first indications of the broadband 50-150 MHz e-p instability in a 1.2 MW neutron production beam. This paper presents details of the design and operation of the SNS damper system as well as results of active damping of the e-p instability in the SNS ring showing a reduction in power of betatron oscillation over the 10-300 MHz band of up to 70%. The spectral content of the beam during operation, with and without the damper system is presented and performance of the damper system is evaluated.

The relationship between Facebook and Instagram appearance-focused activities and body image concerns in young women.

PubMed

Cohen, Rachel; Newton-John, Toby; Slater, Amy

2017-12-01

The present study aimed to identify the specific social networking sites (SNS) features that relate to body image concerns in young women. A total of 259 women aged 18-29years completed questionnaire measures of SNS use (Facebook and Instagram) and body image concerns. It was found that appearance-focused SNS use, rather than overall SNS use, was related to body image concerns in young women. Specifically, greater engagement in photo activities on Facebook, but not general Facebook use, was associated with greater thin-ideal internalisation and body surveillance. Similarly, following appearance-focused accounts on Instagram was associated with thin-ideal internalisation, body surveillance, and drive for thinness, whereas following appearance-neutral accounts was not associated with any body image outcomes. Implications for future SNS research, as well as for body image and disordered eating interventions for young women, are discussed. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Nanoscale Surface Modification of Polycrystalline Tin Sulphide Films during Plasma Treatment

NASA Astrophysics Data System (ADS)

Zimin, S. P.; Gorlachev, E. S.; Dubov, G. A.; Amirov, I. I.; Naumov, V. V.; Gremenok, V. F.; Ivanov, V. A.; Seidi, H. G.

2013-05-01

In this paper, we present a comparative research of the nanoscale modification of the surface morphology of polycrystalline SnS films on glass substrates with two different preferred growth orientations processed in inductively coupled argon plasma. We report a new effect of polycrystalline SnS film surface smoothing during plasma treatment, which can be advantageous for the fabrication of multilayer solar cell devices with SnS absorption layers.

Analgesic effect of Facebook: Priming with online social networking may boost felt relatedness that buffers against physical pain.

PubMed

Ho, Liang-Chu; Wu, Wen-Hsiung; Chiou, Wen-Bin

2016-10-01

Social networking sites (SNSs) are extremely popular for providing users with a convenient platform for acquiring social connections and thereby feeling relatedness. Plenty of literature has shown that mental representations of social support can reduce the perception of physical pain. The current study tested whether thinking about SNS would interfere with users' perceptions of experimentally induced pain. Ninety-six undergraduate Facebook users were recruited to participate in a priming-based experiment. They were randomly assigned to one of the three study conditions (SNS prime, neutral prime, or no prime) via rating the aesthetics of logos. The results showed that participants exposed to SNS primes reported less pain of immersion in hot water than did both control groups (neutral- and no-prime). Felt relatedness mediated the link between SNS primes and diminished pain perceptions. This research provides the first demonstration that thinking about SNS can lower experienced physical pain among Facebook users. Online social networking may serve as an analgesic buffer against pain experience than previously thought. The SNS-enabled analgesia has far reaching implications for pain relief applications and the enhancement of well-being in human-interaction techniques. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Permissive Parenting, Deviant Peer Affiliations, and Delinquent Behavior in Adolescence: the Moderating Role of Sympathetic Nervous System Reactivity.

PubMed

Hinnant, J Benjamin; Erath, Stephen A; Tu, Kelly M; El-Sheikh, Mona

2016-08-01

The present study examined two measures of sympathetic nervous system (SNS) activity as moderators of the indirect path from permissive parenting to deviant peer affiliations to delinquency among a community sample of adolescents. Participants included 252 adolescents (M = 15.79 years; 53 % boys; 66 % European American, 34 % African American). A multi-method design was employed to address the research questions. Two indicators of SNS reactivity, skin conductance level reactivity (SCLR) and cardiac pre-ejection period reactivity (PEPR) were examined. SNS activity was measured during a baseline period and a problem-solving task (star-tracing); reactivity was computed as the difference between the task and baseline periods. Adolescents reported on permissive parenting, deviant peer affiliations, externalizing behaviors, and substance use (alcohol, marijuana). Analyses revealed indirect effects between permissive parenting and delinquency via affiliation with deviant peers. Additionally, links between permissive parenting to affiliation with deviant peers and affiliation with deviant peers to delinquency was moderated by SNS reactivity. Less SNS reactivity (less PEPR and/or less SCLR) were risk factors for externalizing problems and alcohol use. Findings highlight the moderating role of SNS reactivity in parenting and peer pathways that may contribute to adolescent delinquency and point to possibilities of targeted interventions for vulnerable youth.

Permissive Parenting, Deviant Peer Affiliations, and Delinquent Behavior in Adolescence: The Moderating Role of Sympathetic Nervous System Reactivity

PubMed Central

Hinnant, J. Benjamin; Erath, Stephen A.; Tu, Kelly M.; El-Sheikh, Mona

2015-01-01

The present study examined two measures of sympathetic nervous system (SNS) activity as moderators of the indirect path from permissive parenting to deviant peer affiliations to delinquency among a community sample of adolescents. Participants included 252 adolescents (M = 15.79 years; 53% boys; 66% European American, 34% African American). A multi-method design was employed to address the research questions. Two indicators of SNS reactivity, skin conductance level reactivity (SCLR) and cardiac pre-ejection period reactivity (PEPR) were examined. SNS activity was measured during a baseline period and a problem-solving task (star-tracing); reactivity was computed as the difference between the task and baseline periods. Adolescents reported on permissive parenting, deviant peer affiliations, externalizing behaviors, and substance use (alcohol, marijuana). Analyses revealed indirect effects between permissive parenting and delinquency via affiliation with deviant peers. Additionally, links between permissive parenting to affiliation with deviant peers and affiliation with deviant peers to delinquency was moderated by SNS reactivity. Less SNS reactivity (less PEPR and/or less SCLR) were risk factors for externalizing problems and alcohol use. Findings highlight the moderating role of SNS reactivity in parenting and peer pathways that may contribute to adolescent delinquency and point to possibilities of targeted interventions for vulnerable youth. PMID:26667026

Evidence of the paradoxical effect of social network support: A study among Filipino domestic workers in China.

PubMed

Mendoza, Norman B; Mordeno, Imelu G; Latkin, Carl A; Hall, Brian J

2017-09-01

Labor migrants are at an increased risk for poor mental health. Post-migration stressors contribute significantly to this risk. Social network supports are vitally important to protect health but little is known about the role of social network supports among labor migrants. The current study evaluated the role of migration stressors on poor mental health among Filipino female domestic workers (FDW) and whether family and friend social network support (SNS) modified this relationship. Data were collected from 261 FDWs in Macau, China from May to September 2013. Hierarchical multiple regression was conducted to test for direct and moderating effects of social networks on psychological distress. Post-migration stress was associated with increased anxiety, depression, somatization, and post-traumatic stress disorder symptoms. SNS from family was not associated with the four psychological symptoms nor did it modify the association between stress and these symptoms. SNS from friends was positively associated with these symptoms, and significantly moderated the relationship between stress and these symptoms. Counterintuitive to the known buffering effects of SNS, greater SNS was associated with greater psychological symptoms among FDWs exposed to post-migration stressors. The present findings suggest that reliance on SNS to cope with post-migration stressors may worsen psychological distress. Copyright © 2017. Published by Elsevier B.V.

Role of the speech-language pathologist: augmentative and alternative communication for acute care patients with severe communication impairments.

PubMed

Vento-Wilson, Margaret T; McGuire, Anthony; Ostergren, Jennifer A

2015-01-01

Severe communication deficits occur frequently in acute care. Augmentative and alternative communication (AAC) may improve patient-nurse communication, yet it remains underutilized. The objective of this study was to assess the impact of training student nurses (SNs) in acute and critical care on the use of AAC with regard to confidence levels and likelihood of implementation of AAC by SNs in acute care. Training in AAC techniques was provided to SNs. A pretraining and posttraining assessment was completed along with follow-up surveys conducted after the SNs had an opportunity to use AAC. A 6-fold increase in confidence (P < .01) was reported by the SNs after AAC training, as was an approximately 3-fold increase in likelihood of use (P < .01). The reliable yes/no was the most reported AAC technique (34.7% of the students). Providing SNs with AAC tools accompanied by brief training increases their confidence in the use of AAC and the likelihood that they will use them. Inclusion of AAC education in nursing curricula and nursing orientations could be an important step in risk reduction among patients with severe communication disorders. Further study is needed of the relationship between training student nurses in the use of AAC as a way to change practice and improve communication outcomes.

Social network site addiction - an overview.

PubMed

Andreassen, Cecilie Schou; Pallesen, Ståle

2014-01-01

Research into frequent, excessive, and compulsive social network activity has increased the last years, in which terms such as "social network site addiction" and "Facebook addiction" have been used interchangeably. The aim of this review is to offer more knowledge and better understanding of social network site addiction (SNS-addiction) among researchers as well as clinicians by presenting a narrative overview of the research field in terms of definition, measurement, antecedents, consequences, and treatment as well as recommendations for future research efforts. Seven different measures of SNS-addiction have been developed, although they have to a very little extent been validated against each other. The small number of studies conducted so far on this topic suggests that SNS-addiction is associated with health-related, academic, and interpersonal problems/issues. However such studies have relied on a simple cross-sectional study design. It is therefore hard to draw any conclusions about potential causality and long-term effects at this point, beyond hypothetical speculations. Empirical studies suggest that SNS-addiction is caused by dispositional factors (e.g., personality, needs, self-esteem), although relevant explanatory socio-cultural and behavioral reinforcement factors remain to be empirically explored. No well-documented treatment for SNS-addiction exists, but knowledge gained from Internet addiction treatment approaches might be transferable to SNS-addiction. Overall, the research on this topic is in its infancy, and as such the SNS-addiction construct needs further conceptual and empirical exploration. There is a great demand for studies using careful longitudinal designs and studies which include objective measures of both behavior and health based on broad representative samples.

Friends' Alcohol-Related Social Networking Site Activity Predicts Escalations in Adolescent Drinking: Mediation by Peer Norms.

PubMed

Nesi, Jacqueline; Rothenberg, W Andrew; Hussong, Andrea M; Jackson, Kristina M

2017-06-01

Adolescents' increased use of social networking sites (SNS) coincides with a developmental period of heightened risk for alcohol use initiation. However, little is known regarding associations between adolescents' SNS use and drinking initiation nor the mechanisms of this association. This study examined longitudinal associations among adolescents' exposure to friends' alcohol-related SNS postings, alcohol-favorable peer injunctive norms, and initiation of drinking behaviors. Participants were 658 high-school students who reported on posting of alcohol-related SNS content by self and friends, alcohol-related injunctive norms, and other developmental risk factors for alcohol use at two time points, 1 year apart. Participants also reported on initiation of three drinking behaviors: consuming a full drink, becoming drunk, and heavy episodic drinking (three or more drinks per occasion). Probit regression analyses were used to predict initiation of drinking behaviors from exposure to alcohol-related SNS content. Path analyses examined mediation of this association by peer injunctive norms. Exposure to friends' alcohol-related SNS content predicted adolescents' initiation of drinking and heavy episodic drinking 1 year later, controlling for demographic and known developmental risk factors for alcohol use (i.e., parental monitoring and peer orientation). In addition, alcohol-favorable peer injunctive norms statistically mediated the relationship between alcohol-related SNS exposure and each drinking milestone. Results suggest that social media plays a unique role in contributing to peer influence processes surrounding alcohol use and highlight the need for future investigative and preventive efforts to account for adolescents' changing social environments. Copyright © 2017 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Electrochemical growth of SnS thin film: application to the photocatalytic degradation of rhodamine B under visible light

NASA Astrophysics Data System (ADS)

Kabouche, S.; Louafi, Y.; Bellal, B.; Trari, M.

2017-08-01

A facile and template-free wet electrochemical technique was used to deposit SnS on tin substrate. Longer time (>40 min) is required for the formation of the chalcogenide thin films and the potential must be carefully controlled to come out with a rough chemical identification of sulfide deposited at low potential scan. The deposition potential is selected from the cyclic voltammetry to preclude the oxidation of SnS to SnS2. The SnS films are uniform and well adhered to the substrate. They were characterized by X-ray diffraction, UV-Vis spectroscopy and electrochemical impedance spectroscopy (EIS). SnS crystallizes in an orthorhombic symmetry (SG: Pnma) and a crystallite size of 42 nm was obtained. The Mott-Schottky plot exhibited a linear behavior with a negative slope, characteristic of p-type conductivity. Holes density of 9.75 × 1020 cm-3, a flat band potential of 0.56 V SCE and a depletion width of 38 nm were determined. The valence band was located at (-5.41 eV/0.66 V) and derives mainly from S 2-: 3 p while the conduction band (3.8 eV/-0.95 V) was primarily made up of Sn2+: 5 p orbital. The EIS spectra measured over the frequency range (3 × 10-3-105 Hz) revealed mainly a bulk contribution. On application, rhodamine B was successfully oxidized on SnS films, 38% of the initial concentration (10 mg L-1) disappeared after 4 h of exposure to solar light (90 mW cm-2).

New Professionalism Challenges in Medical Training: An Exploration of Social Networking

PubMed Central

Kesselheim, Jennifer C.; Batra, Maneesh; Belmonte, Frank; Boland, Kimberly A.; McGregor, Robert S.

2014-01-01

Background Innovative online technology can enhance the practice of medicine, yet it also may be a forum for unprofessional behavior. Objective We surveyed program directors regarding their perceptions and experiences with residents' use of social networking sites (SNS). Methods In September 2011, we sent an online survey to program directors and associate program directors of pediatrics residency programs within the United States who are members of the Association of Pediatric Program Directors. Results A total of 162 program directors or associate program directors (representing 50% of residency programs) responded to the survey. One-third of respondents are “very familiar” with SNS and 23% use them “daily or often.” Most respondents (70%) rated “friending” peers as “completely appropriate,” whereas only 1% of respondents rated “friending” current or past patients as “completely appropriate.” More than one half of respondents believe inappropriate behavior on SNS is “somewhat” or “very” prevalent, and 91% are “somewhat” or “very” concerned that the prevalence of inappropriate behavior on SNS may increase. The most commonly reported problematic online activity was posting inappropriate comments about the workplace. Posting of inappropriate comments about self, patients, and staff also was observed. Residency programs commonly educate trainees about SNS during intern orientation (45%), or using written guidelines (29%) and ad hoc remediation (16%). Conclusions As educators teach trainees principles of online professionalism, appropriate use of SNS needs to be included in the training process. Curricular efforts may be hindered by some program directors' lack of familiarity with SNS. PMID:24701318

Shared responsibility: school nurses' experience of collaborating in school-based interprofessional teams.

PubMed

Reuterswärd, Marina; Hylander, Ingrid

2017-06-01

The Swedish Education Act (2011) mandated a new combination of services to boost students' physical health, their mental health and special education through interprofessional pupil health and well-being (PH) teams. For Swedish school nurses, providing these services presents new challenges. To describe how Swedish school nurses experience their work and collaboration within the interprofessional PH teams. Twenty-five school nurses (SNs) were interviewed in five focus groups. Content analysis was used to examine the data and to explore SNs' workplace characteristics by using the components of the sense of coherence (SOC) framework. SNs' experiences of work and collaboration within PH teams can be described using three domains: the expectations of others regarding SNs' roles, SNs' contributions to pupils' health and well-being, and collaboration among SNs within PH teams. The results indicate a discrepancy between SNs' own experiences of their contribution and their experiences of other professionals' expectations regarding those contributions. Some duties were perceived as expected, comprehensible, manageable and meaningful, while other duties - though expected - were perceived as less meaningful, taking time away from school-related matters. Other duties that were not explicitly expected - promoting general health and creating safety zones for pupils, teachers and parents, for example - were nonetheless perceived as meaningful. Collaboration within PH teams was considered meaningful, comprehensible and manageable only if the objectives of the team meetings were clear, if other professionals were available and if professional roles on the team were clearly communicated. The SNs reported a lack of clarity regarding their role in PH and its implementation in schools, indicating that professionals in PH teams need to discuss collaboration so as to find their niche given the new conditions. SOC theory emerged as a useful framework for discussing concrete work-related factors in the school environment. © 2016 Nordic College of Caring Science.

Noncoplanar VMAT for nasopharyngeal tumors: Plan quality versus treatment time.

PubMed

Wild, Esther; Bangert, Mark; Nill, Simeon; Oelfke, Uwe

2015-05-01

The authors investigated the potential of optimized noncoplanar irradiation trajectories for volumetric modulated arc therapy (VMAT) treatments of nasopharyngeal patients and studied the trade-off between treatment plan quality and delivery time in radiation therapy. For three nasopharyngeal patients, the authors generated treatment plans for nine different delivery scenarios using dedicated optimization methods. They compared these scenarios according to dose characteristics, number of beam directions, and estimated delivery times. In particular, the authors generated the following treatment plans: (1) a 4π plan, which is a not sequenced, fluence optimized plan that uses beam directions from approximately 1400 noncoplanar directions and marks a theoretical upper limit of the treatment plan quality, (2) a coplanar 2π plan with 72 coplanar beam directions as pendant to the noncoplanar 4π plan, (3) a coplanar VMAT plan, (4) a coplanar step and shoot (SnS) plan, (5) a beam angle optimized (BAO) coplanar SnS IMRT plan, (6) a noncoplanar BAO SnS plan, (7) a VMAT plan with rotated treatment couch, (8) a noncoplanar VMAT plan with an optimized great circle around the patient, and (9) a noncoplanar BAO VMAT plan with an arbitrary trajectory around the patient. VMAT using optimized noncoplanar irradiation trajectories reduced the mean and maximum doses in organs at risk compared to coplanar VMAT plans by 19% on average while the target coverage remains constant. A coplanar BAO SnS plan was superior to coplanar SnS or VMAT; however, noncoplanar plans like a noncoplanar BAO SnS plan or noncoplanar VMAT yielded a better plan quality than the best coplanar 2π plan. The treatment plan quality of VMAT plans depended on the length of the trajectory. The delivery times of noncoplanar VMAT plans were estimated to be 6.5 min in average; 1.6 min longer than a coplanar plan but on average 2.8 min faster than a noncoplanar SnS plan with comparable treatment plan quality. The authors' study reconfirms the dosimetric benefits of noncoplanar irradiation of nasopharyngeal tumors. Both SnS using optimized noncoplanar beam ensembles and VMAT using an optimized, arbitrary, noncoplanar trajectory enabled dose reductions in organs at risk compared to coplanar SnS and VMAT. Using great circles or simple couch rotations to implement noncoplanar VMAT, however, was not sufficient to yield meaningful improvements in treatment plan quality. The authors estimate that noncoplanar VMAT using arbitrary optimized irradiation trajectories comes at an increased delivery time compared to coplanar VMAT yet at a decreased delivery time compared to noncoplanar SnS IMRT.

Sex-Related Online Behaviors, Perceived Peer Norms and Adolescents’ Experience with Sexual Behavior: Testing an Integrative Model

PubMed Central

Doornwaard, Suzan M.; ter Bogt, Tom F. M.; Reitz, Ellen; van den Eijnden, Regina J. J. M.

2015-01-01

Research on the role of sex-related Internet use in adolescents’ sexual development has often isolated the Internet and online behaviors from other, offline influencing factors in adolescents’ lives, such as processes in the peer domain. The aim of this study was to test an integrative model explaining how receptive (i.e., use of sexually explicit Internet material [SEIM]) and interactive (i.e., use of social networking sites [SNS]) sex-related online behaviors interrelate with perceived peer norms in predicting adolescents’ experience with sexual behavior. Structural equation modeling on longitudinal data from 1,132 Dutch adolescents (Mage T1 = 13.95; range 11-17; 52.7% boys) demonstrated concurrent, direct, and indirect effects between sex-related online behaviors, perceived peer norms, and experience with sexual behavior. SEIM use (among boys) and SNS use (among boys and girls) predicted increases in adolescents’ perceptions of peer approval of sexual behavior and/or in their estimates of the numbers of sexually active peers. These perceptions, in turn, predicted increases in adolescents’ level of experience with sexual behavior at the end of the study. Boys’ SNS use also directly predicted increased levels of experience with sexual behavior. These findings highlight the need for multisystemic research and intervention development to promote adolescents’ sexual health. PMID:26086606

Sex-Related Online Behaviors, Perceived Peer Norms and Adolescents' Experience with Sexual Behavior: Testing an Integrative Model.

PubMed

Doornwaard, Suzan M; ter Bogt, Tom F M; Reitz, Ellen; van den Eijnden, Regina J J M

2015-01-01

Research on the role of sex-related Internet use in adolescents' sexual development has often isolated the Internet and online behaviors from other, offline influencing factors in adolescents' lives, such as processes in the peer domain. The aim of this study was to test an integrative model explaining how receptive (i.e., use of sexually explicit Internet material [SEIM]) and interactive (i.e., use of social networking sites [SNS]) sex-related online behaviors interrelate with perceived peer norms in predicting adolescents' experience with sexual behavior. Structural equation modeling on longitudinal data from 1,132 Dutch adolescents (M(age) T1 = 13.95; range 11-17; 52.7% boys) demonstrated concurrent, direct, and indirect effects between sex-related online behaviors, perceived peer norms, and experience with sexual behavior. SEIM use (among boys) and SNS use (among boys and girls) predicted increases in adolescents' perceptions of peer approval of sexual behavior and/or in their estimates of the numbers of sexually active peers. These perceptions, in turn, predicted increases in adolescents' level of experience with sexual behavior at the end of the study. Boys' SNS use also directly predicted increased levels of experience with sexual behavior. These findings highlight the need for multisystemic research and intervention development to promote adolescents' sexual health.

Threefold growth efficiency improvement of silica nanosprings by using silica nanosprings as a substrate

NASA Astrophysics Data System (ADS)

Corti, Giancarlo; Brown, Justin; Rajabi, Negar; McIlroy, D. N.

2018-03-01

The growth efficiency of one-dimension (1D) nanostructures via the vapor-liquid-solid process is commonly attributed to parameters such as precursor vapor pressure, substrate temperature, and the choice of the catalyst. The work presented herein is an investigation of the use of silica nanosprings (SNs) as a 3D substrate for improving the growth efficiency of SN themselves. SNs are a 1D nanomaterial that form a nonwoven structure with optimal geometric characteristics and surface properties that mitigate collisions between growing nanosprings and ripening of the gold catalyst, which should improve SN yield. Nanospring growth, for an eight hour period, on an SN coated surface relative to an equivalent flat substrate increased from ≈25 mgh-1 to ≈80 mgh-1, respectively. All things being equal, by splitting the typical amount of catalyst, in this case gold, between the first and second growth, the double growth procedure produced more than three times more nanosprings than the equivalent single growth of a SN. In addition, using an SN as a substrate increased the sustained growth condition from four to eight hours, and thus increased by a factor of ten the gravimetric yield of SNs relative to the mass of gold used.

Sacral Nerve Stimulation For Urinary Urge Incontinence, Urgency-Frequency, Urinary Retention, and Fecal Incontinence

PubMed Central

2005-01-01

Executive Summary Objective The aim of this review was to assess the effectiveness, safety, and cost of sacral nerve stimulation (SNS) to treat urinary urge incontinence, urgency-frequency, urinary retention, and fecal incontinence. Background: Condition and Target Population Urinary urge incontinence, urgency-frequency, urinary retention, and fecal incontinence are prevalent, yet rarely discussed, conditions. They are rarely discussed because patients may be uncomfortable disclosing their symptoms to a health professional or may be unaware that there are treatment options for these conditions. Briefly, urge incontinence is an involuntary loss of urine upon a sudden urge. Urgency-frequency is an uncontrollable urge to void, which results in frequent, small-volume voids. People with urgency-frequency may or may not also experience chronic pelvic pain. Urinary retention refers to the inability to void despite having the urge to void. It can be caused by a hypocontractile detrusor (weak or no bladder muscle contraction) or obstruction due to urethral overactivity. Fecal incontinence is a loss of voluntary bowel control. The prevalence of urge incontinence, urgency-frequency, and urinary retention in the general population is 3.3% to 8.2%, and the prevalence of fecal incontinence is 1.4% to 1.9%. About three-quarters of these people will be successfully treated by behaviour and/or drug therapy. For those who do not respond to these therapies, the options for treatment are management with diapers or pads, or surgery. The surgical procedures are generally quite invasive, permanent, and are associated with complications. Pads and/or diapers are used throughout the course of treatment as different therapies are tried. Patients who respond successfully to treatment may still require pads or diapers, but to a lesser extent. The Technology Being Reviewed: Sacral Nerve Stimulation Sacral nerve stimulation is a procedure where a small device attached to an electrode is implanted in the abdomen or buttock to stimulate the sacral nerves in an attempt to manage urinary urge incontinence, urgency-frequency, urinary retention, and fecal incontinence. The device was originally developed to manage urinary urge incontinence; however, it has also been used in patients with urgency-frequency, urinary retention, and fecal incontinence. SNS is intended for patients who are refractory to behaviour, drug, and/or interventional therapy. There are 2 phases in the SNS process: first, patients must undergo a test stimulation phase to determine if they respond to sacral nerve stimulation. If there is a 50% or greater improvement in voiding function, then the patient is considered a candidate for the next phase, implantation. Review Strategy The standard Medical Advisory Secretariat search strategy was used to locate international health technology assessments and English-language journal articles published from 2000 to November 2004. The Medical Advisory Secretariat also conducted Internet searches of Medscape (1) and the manufacturer’s website (2) to identify product information and recent reports on trials that were unpublished but that were presented at international conferences. In addition, the Web site Current Controlled Trials (3) was searched for ongoing randomized controlled trials (RCTs) investigating the role of sacral nerve stimulation in the management of voiding conditions. Summary of Findings Four health technology assessments were found that reviewed SNS in patients with urge incontinence, urgency-frequency, and/or urinary retention. One assessment was found that reviewed SNS in patients with fecal incontinence. The assessments consistently reported that SNS was an effective technology in managing these voiding conditions in patients who did not respond to drug or behaviour therapy. They also reported that there was a substantial complication profile associated with SNS. Complication rates ranged from 33% to 50%. However, none of the assessments reported that they found any incidences of permanent injury or death associated with the device. The health technology assessments for urge incontinence, urgency-frequency, and urinary retention included (RCTs (level 2) as their primary source of evidence for their conclusions. The assessment of fecal incontinence based its conclusions on evidence from case series (level 4). Because there was level 2 data available for the use of SNS in patients with urinary conditions, the Medical Advisory Secretariat chose to review thoroughly the RCTs included in the assessments and search for publications since the assessments were released. However, for the health technology assessment for fecal incontinence, which contained only level 4 evidence, the Medical Advisory Secretariat searched for studies on SNS and fecal incontinence that were published since that assessment was released. Urge Incontinence Two RCTs were identified that compared SNS to no treatment in patients with refractory urge incontinence. Both RCTs reported significant improvements (> 50% improvement in voiding function) in the SNS group for number of incontinence episodes per day, number of pads used per day, and severity of incontinence episodes. Urgency-Frequency (With or Without Chronic Pelvic Pain) One RCT was identified that compared SNS to no treatment in patients with refractory urgency-frequency. The RCT reported significant improvements in urgency-frequency symptoms in the SNS group (average volume per void, detrusor pressure). In addition to the RCT, 1 retrospective review and 2 prospective case series were identified that measured pelvic pain associated with urgency-frequency in patients who underwent SNS. All 3 studies reported a significant decrease in pain at median follow-up. Urinary Retention One RCT was identified that compared SNS to no treatment in patients with refractory urinary retention. The RCT reported significant improvements in urinary retention in the SNS group compared to the control group for number of catheterizations required and number of voids per day. In addition to this RCT, 1 case series was also identified investigating SNS in women with urinary retention. This study also found that there were significant improvements in urinary retention after the women had received the SNS implants. Fecal Incontinence Three case series were identified that investigated the role of SNS in patients with fecal incontinence. All 3 reported significant improvements in fecal incontinence symptoms (number of incontinent episodes per week) after the patients received the SNS implants. Long-Term Follow-up None of the studies identified followed patients until the point of battery failure. Of the 6 studies identified describing the long-term follow-up of patients with SNS, follow-up periods ranged from 1.5 years to over 5 years. None of the long-term follow-up studies included patients with fecal incontinence. All of the studies reported that most of the patients who had SNS had at least a 50% improvement in voiding function (range 58%–77%). These studies also reported the number of patients who had their device explanted in the follow-up period. The rates of explantation ranged from 12% to 21%. Safety, Complications, and Quality of Life A 33% surgical revision rate was reported in an analysis of the safety of 3 RCTs comparing SNS to no treatment in patients with urge incontinence, urgency-frequency, or urinary retention. The most commonly reported adverse effects were pain at the implant site and lead migration. Despite the high rate of surgical revision, there were no reports of permanent injury or death in any of the studies or health technology assessments identified. Additionally, patients consistently said that they would recommend the procedure to a friend or family member. Economic Analysis One health technology assessment and 1 abstract were found that investigated the costing factors pertinent to SNS. The authors of this assessment did their own “indicative analysis” and found that SNS was not more cost-effective than using incontinence supplies. However, the assessment did not account for quality of life. Conversely, the authors of the abstract found that SNS was more cost-effective than incontinence supplies alone; however, they noted that in the first year after SNS, it is much more expensive than only incontinence supplies. This is owing to the cost of the procedure, and the adjustments required to make the device most effective. They also noted the positive effects that SNS had on quality of life. Conclusions and Implications In summary, there is level 2 evidence to support the effectiveness of SNS to treat people with urge incontinence, urgency-frequency, or urinary retention. There is level 4 evidence to support the effectiveness of SNS to treat people with fecal incontinence. To qualify for SNS, people must meet the following criteria: Be refractory to behaviour and/or drug therapy Have had a successful test stimulation before implantation; successful test stimulation is defined by a 50% or greater improvement in voiding function based on the results of a voiding diary. Test stimulation periods range from 3 to 7 days for patients with urinary dysfunctions, and from 2 to 3 weeks for patients with fecal incontinence. Be able to record voiding diary data, so that clinical results of the implantation can be evaluated. Patients with stress incontinence, urinary retention due to obstruction and neurogenic conditions (such as diabetes with peripheral nerve involvement) are ineligible for sacral nerve stimulation. Physicians will need to learn how to use the InterStim System for Urinary Control. Requirements for training include these: Physicians must be experienced in the diagnosis and treatment of lower urinary tract disorders and should be trained in the implantation and use of the InterStim System for Urinary Control. Training should include the following: Participation in a seminar or workshop that includes instructional and laboratory training on SNS. This seminar should include a review of the evidence on SNS with emphasis on techniques to prevent adverse events. Completion of proctoring by a physician experienced in SNS for the first 2 test stimulations and the first 2 implants PMID:23074472

Transverse beam stability measurement and analysis for the SNS accumulator ring

DOE PAGES

Xie, Zaipeng; Deibele, Craig; Schulte, Michael J.; ...

2015-07-01

In a Field-programmable gate array (FPGA) based transverse feedback damper system we implemented in the Spallation Neutron Source (SNS) accumulator ring with the intention to stabilize the electron-proton (e-p) instability in a frequency range from 1 MHz to 300 MHz. The transverse damper could also be used as a diagnostic tool by measuring the beam transfer function (BTF). An analysis of the BTF measurement provides the stability diagram for the production beam at SNS. Our paper describes the feedback damper system and its set-up as the BTF diagnostic tool. Experimental BTF results are presented and beam stability analysis is performedmore » based on the BTF measurements for the SNS accumulator ring.« less

Gender Differences in the Continuance of Online Social Networks

NASA Astrophysics Data System (ADS)

Shi, Na; Cheung, Christy M. K.; Lee, Matthew K. O.; Chen, Huaping

Social network sites (SNS) have become increasingly popular in the past few years benefiting from the rapid growth of Web 2.0 applications. However, research on the adoption and usage of SNS is limited. In this study, we attempt to understand users' continuance intention to use SNS and investigate the role of gender. A research model was developed and tested with 213 respondents from an online survey. The results confirm that users' continuance intention to use SNS is strongly determined by satisfaction. The effect of disconfirmation of maintaining offline contacts on satisfaction is more important for women, while the effect of disconfirmation of entertainment is more salient for men. Implications of this study for both researchers and practitioners are discussed.

Propofol-induced increase in vascular capacitance is due to inhibition of sympathetic vasoconstrictive activity.

PubMed

Hoka, S; Yamaura, K; Takenaka, T; Takahashi, S

1998-12-01

Venodilation is thought to be one of the mechanisms underlying propofol-induced hypotension. The purpose of this study is to test two hypotheses: (1) propofol increases systemic vascular capacitance, and (2) the capacitance change produced by propofol is a result of an inhibition of sympathetic vasoconstrictor activity. In 33 Wistar rats previously anesthetized with urethane and ketamine, vascular capacitance was examined before and after propofol infusion by measuring mean circulatory filling pressure (Pmcf). The Pmcf was measured during a brief period of circulatory arrest produced by inflating an indwelling balloon in the right atrium. Rats were assigned into four groups: an intact group, a sympathetic nervous system (SNS)-block group produced by hexamethonium infusion, a SNS-block + noradrenaline (NA) group, and a hypovolemic group. The Pmcf was measured at a control state and 2 min after a bolus administration of 2, 10, and 20 mg/kg of propofol. The mean arterial pressure (MAP) was decreased by propofol dose-dependently in intact, hypovolemic, and SNS-block groups, but the decrease in MAP was less in the SNS-block group (-25%) than in the intact (-50%) and hypovolemic (-61%) groups. In the SNS-block + NA group, MAP decreased only at 20 mg/kg of propofol (-18%). The Pmcf decreased in intact and hypovolemic groups in a dose-dependent fashion but was unchanged in the SNS-block and SNS-block + NA groups. The results have provided two principal findings: (1) propofol decreases Pmcf dose-dependently, and (2) the decrease in Pmcf by propofol is elicited only when the sympathetic nervous system is intact, suggesting that propofol increases systemic vascular capacitance as a result of an inhibition of sympathetic nervous system.

Second Neoplasms in Survivors of Childhood Cancer: Findings From the Childhood Cancer Survivor Study Cohort

PubMed Central

Meadows, Anna T.; Friedman, Debra L.; Neglia, Joseph P.; Mertens, Ann C.; Donaldson, Sarah S.; Stovall, Marilyn; Hammond, Sue; Yasui, Yutaka; Inskip, Peter D.

2009-01-01

Purpose To review the reports of subsequent neoplasms (SNs) in the Childhood Cancer Survivor Study (CCSS) cohort that were made through January 1, 2006, and published before July 31, 2008, and to discuss the host-, disease-, and therapy-related risk factors associated with SNs. Patients and Methods SNs were ascertained by survivor self-reports and subsequently confirmed by pathology findings or medical record review. Cumulative incidence of SNs and standardized incidence ratios for second malignant neoplasms (SMNs) were calculated. The impact of host-, disease-, and therapy-related risk factors was evaluated by Poisson regression. Results Among 14,358 cohort members, 730 reported 802 SMNs (excluding nonmelanoma skin cancers). This represents a 2.3-fold increase in the number of SMNs over that reported in the first comprehensive analysis of SMNs in the CCSS cohort, which was done 7 years ago. In addition, 66 cases of meningioma and 1,007 cases of nonmelanoma skin cancer were diagnosed. The 30-year cumulative incidence of SMNs was 9.3% and that of nonmelanoma skin cancer was 6.9%. Risk of SNs remains elevated for more than 20 years of follow-up for all primary childhood cancer diagnoses. In multivariate analyses, risks differ by SN subtype, but include radiotherapy, age at diagnosis, sex, family history of cancer, and primary childhood cancer diagnosis. Female survivors whose primary childhood cancer diagnosis was Hodgkin's lymphoma or sarcoma and who received radiotherapy are at particularly increased risk. Analyses of risk associated with radiotherapy demonstrated different dose-response curves for specific SNs. Conclusion Childhood cancer survivors are at a substantial and increasing risk for SNs, including nonmelanoma skin cancer and meningiomas. Health care professionals should understand the magnitude of these risks to provide individuals with appropriate counseling and follow-up. PMID:19255307

Short and long sympathetic-sensory feedback loops in white fat

PubMed Central

Ryu, Vitaly

2014-01-01

We previously demonstrated white adipose tissue (WAT) innervation using the established WAT retrograde sympathetic nervous system (SNS)-specific transneuronal viral tract tracer pseudorabies virus (PRV152) and showed its role in the control of lipolysis. Conversely, we demonstrated WAT sensory innervation using the established anterograde sensory system (SS)-specific transneuronal viral tracer, the H129 strain of herpes simplex virus-1, with sensory nerves showing responsiveness with increases in WAT SNS drive. Several brain areas were part of the SNS outflow to and SS inflow from WAT between these studies suggesting SNS-SS feedback loops. Therefore, we injected both PRV152 and H129 into inguinal WAT (IWAT) of Siberian hamsters. Animals were perfused on days 5 and 6 postinoculation after H129 and PRV152 injections, respectively, and brains, spinal cords, sympathetic, and dorsal root ganglia (DRG) were processed for immunohistochemical detection of each virus across the neuroaxis. The presence of H129+PRV152-colocalized neurons (∼50%) in the spinal segments innervating IWAT suggested short SNS-SS loops with significant coinfections (>60%) in discrete brain regions, signifying long SNS-SS loops. Notably, the most highly populated sites with the double-infected neurons were the medial part of medial preoptic nucleus, medial preoptic area, hypothalamic paraventricular nucleus, lateral hypothalamus, periaqueductal gray, oral part of the pontine reticular nucleus, and the nucleus of the solitary tract. Collectively, these results strongly indicate the neuroanatomical reality of the central SNS-SS feedback loops with short loops in the spinal cord and long loops in the brain, both likely involved in the control of lipolysis or other WAT pad-specific functions. PMID:24717676

Social Networking Sites, Depression, and Anxiety: A Systematic Review

PubMed Central

Kern, Margaret L; Rickard, Nikki S

2016-01-01

Background Social networking sites (SNSs) have become a pervasive part of modern culture, which may also affect mental health. Objective The aim of this systematic review was to identify and summarize research examining depression and anxiety in the context of SNSs. It also aimed to identify studies that complement the assessment of mental illness with measures of well-being and examine moderators and mediators that add to the complexity of this environment. Methods A multidatabase search was performed. Papers published between January 2005 and June 2016 relevant to mental illness (depression and anxiety only) were extracted and reviewed. Results Positive interactions, social support, and social connectedness on SNSs were consistently related to lower levels of depression and anxiety, whereas negative interaction and social comparisons on SNSs were related to higher levels of depression and anxiety. SNS use related to less loneliness and greater self-esteem and life satisfaction. Findings were mixed for frequency of SNS use and number of SNS friends. Different patterns in the way individuals with depression and individuals with social anxiety engage with SNSs are beginning to emerge. Conclusions The systematic review revealed many mixed findings between depression, anxiety, and SNS use. Methodology has predominantly focused on self-report cross-sectional approaches; future research will benefit from leveraging real-time SNS data over time. The evidence suggests that SNS use correlates with mental illness and well-being; however, whether this effect is beneficial or detrimental depends at least partly on the quality of social factors in the SNS environment. Understanding these relationships will lead to better utilization of SNSs in their potential to positively influence mental health. PMID:27881357

The influence of social networking sites on health behavior change: a systematic review and meta-analysis

PubMed Central

Laranjo, Liliana; Arguel, Amaël; Neves, Ana L; Gallagher, Aideen M; Kaplan, Ruth; Mortimer, Nathan; Mendes, Guilherme A; Lau, Annie Y S

2015-01-01

Objective Our aim was to evaluate the use and effectiveness of interventions using social networking sites (SNSs) to change health behaviors. Materials and methods Five databases were scanned using a predefined search strategy. Studies were included if they focused on patients/consumers, involved an SNS intervention, had an outcome related to health behavior change, and were prospective. Studies were screened by independent investigators, and assessed using Cochrane's ‘risk of bias’ tool. Randomized controlled trials were pooled in a meta-analysis. Results The database search retrieved 4656 citations; 12 studies (7411 participants) met the inclusion criteria. Facebook was the most utilized SNS, followed by health-specific SNSs, and Twitter. Eight randomized controlled trials were combined in a meta-analysis. A positive effect of SNS interventions on health behavior outcomes was found (Hedges’ g 0.24; 95% CI 0.04 to 0.43). There was considerable heterogeneity (I2 = 84.0%; T2 = 0.058) and no evidence of publication bias. Discussion To the best of our knowledge, this is the first meta-analysis evaluating the effectiveness of SNS interventions in changing health-related behaviors. Most studies evaluated multi-component interventions, posing problems in isolating the specific effect of the SNS. Health behavior change theories were seldom mentioned in the included articles, but two particularly innovative studies used ‘network alteration’, showing a positive effect. Overall, SNS interventions appeared to be effective in promoting changes in health-related behaviors, and further research regarding the application of these promising tools is warranted. Conclusions Our study showed a positive effect of SNS interventions on health behavior-related outcomes, but there was considerable heterogeneity. Protocol registration The protocol for this systematic review is registered at http://www.crd.york.ac.uk/PROSPERO with the number CRD42013004140. PMID:25005606

Social Networking Sites, Depression, and Anxiety: A Systematic Review.

PubMed

Seabrook, Elizabeth M; Kern, Margaret L; Rickard, Nikki S

2016-11-23

Social networking sites (SNSs) have become a pervasive part of modern culture, which may also affect mental health. The aim of this systematic review was to identify and summarize research examining depression and anxiety in the context of SNSs. It also aimed to identify studies that complement the assessment of mental illness with measures of well-being and examine moderators and mediators that add to the complexity of this environment. A multidatabase search was performed. Papers published between January 2005 and June 2016 relevant to mental illness (depression and anxiety only) were extracted and reviewed. Positive interactions, social support, and social connectedness on SNSs were consistently related to lower levels of depression and anxiety, whereas negative interaction and social comparisons on SNSs were related to higher levels of depression and anxiety. SNS use related to less loneliness and greater self-esteem and life satisfaction. Findings were mixed for frequency of SNS use and number of SNS friends. Different patterns in the way individuals with depression and individuals with social anxiety engage with SNSs are beginning to emerge. The systematic review revealed many mixed findings between depression, anxiety, and SNS use. Methodology has predominantly focused on self-report cross-sectional approaches; future research will benefit from leveraging real-time SNS data over time. The evidence suggests that SNS use correlates with mental illness and well-being; however, whether this effect is beneficial or detrimental depends at least partly on the quality of social factors in the SNS environment. Understanding these relationships will lead to better utilization of SNSs in their potential to positively influence mental health. ©Elizabeth M Seabrook, Margaret L Kern, Nikki S Rickard. Originally published in JMIR Mental Health (http://mental.jmir.org), 23.11.2016.

Associations between the use of social networking sites and unhealthy eating behaviours and excess body weight in adolescents.

PubMed

Sampasa-Kanyinga, Hugues; Chaput, Jean-Philippe; Hamilton, Hayley A

2015-12-14

Unhealthy eating behaviour and excess body weight have been related to sedentary behaviour, particularly screen time, in adolescents; however, little is known about their associations with the use of social networking sites (SNS). We investigated the associations between time spent using SNS and unhealthy eating behaviours (including breakfast skipping, consumption of sugar-sweetened beverages (SSB) and energy drinks) and body weight in adolescents. Data on 9858 students (mean age: 15·2 (SD 1·9) years) in grades 7 through 12 were derived from the 2013 cycle of the Ontario Student Drug Use and Health Survey--a cross-sectional school-based survey of middle and high school students. The majority (81·5%) of students reported daily use of SNS and an additional 10·7% reported using them on an irregular basis. Multivariate logistic regression analyses revealed that the use of SNS was associated with increased odds of skipping breakfast (P trend<0·01) and consuming SSB (P trend<0·01) and energy drinks (P trend<0·01) in a dose-response manner with adjustments for age, sex, ethnicity, socio-economic status, tobacco, alcohol and cannabis use as well as BMI. However, there was no evidence of a significant association between use of SNS and BMI before or after adjusting for all the covariates and unhealthy eating behaviours. In conclusion, our results suggest associations between the use of SNS and unhealthy eating behaviours among youth. Given the popularity of SNS, more efforts are needed to better understand the impact of social networks on eating behaviours and risk of excess weight.

Who You Gonna Call? Responding to a Medical Emergency with the Strategic National Stockpile

DTIC Science & Technology

2004-06-01

pharmaceuticals. The logistical burden on the local and state responders who receive, dispense, and distribute the SNS is considerable. The time and...bulk drugs in the SNS are repackaged on- site , the labeling machines that accompany each of the push packs can be programmed to provide the required...burden on local responders , who already will be facing a significant task in dispensing the SNS materiel to a (potentially) large affected population

Social and parasocial relationships on social network sites and their differential relationships with users' psychological well-being.

PubMed

Baek, Young Min; Bae, Young; Jang, Hyunmi

2013-07-01

With the advent of social network sites (SNSs), people can efficiently maintain preexisting social relationships and make online friendships without offline encounters. While such technological features of SNSs hold a variety of potential for individual and collective benefits, some scholars warn that use of SNSs might lead to socially negative consequences, such as social isolation, erosion of social cohesion, or SNS addiction. This study distinguishes types of SNS relationships, and investigates their relationships with social isolation, interpersonal trust, and SNS addiction. We classify SNS relationships into two types: (a) social relationships based on reciprocity between a user and his/her friends, and (b) parasocial relationships in which an ordinary user is aware of activities of a celebrity (e.g., famous actors, athletes, and others) but not vice versa. Based on achievements in studies of media effect and social psychology, we constructed a set of hypotheses, and tested them using a subsample of SNS users drawn from representative survey data in South Korea. We found that dependency on parasocial relationships is positively related with loneliness but negatively correlated with interpersonal distrust, while dependency on social relationship is negatively correlated with loneliness but positively related with trust. However, more dependency on both social and parasocial relationships are positively related with SNS addiction. Implications based on findings are also discussed.

The independent relationship between trouble controlling Facebook use, time spent on the site and distress.

PubMed

Muench, Fredrick; Hayes, Marie; Kuerbis, Alexis; Shao, Sijing

2015-09-01

There is an emerging literature base on the relationship between maladaptive traits and "addiction" to social networking sites. These studies have operationalized addiction as either spending excessive amounts of time on social networking sites (SNS) or trouble controlling SNS use, but have not assessed the unique contribution of each of these constructs on outcomes in the same models. Moreover, these studies have exclusively been conducted with younger people rather than a heterogeneous sample. This study examined the independent relationship of a brief Facebook addiction scale, time spent on Facebook, and Facebook checking on positive and negative social domains, while controlling for self-esteem and social desirability. Participants were recruited using e-mail, SNS posts and through Amazon's MTurk system. The sample included 489 respondents ages from 18 to approximately 70, who completed a 10-15 minute survey. Results indicate that neither time spent on Facebook nor Facebook checking was significantly associated with either self-esteem, fear of negative social evaluation or social comparison, while SNS addiction symptoms were each independently associated with Facebook usage. Neither time spent on Facebook nor SNS addiction symptoms were associated with positive social relationships. Overall results suggest that time on SNS and trouble controlling use should be considered independent constructs and that interventions should target underlying loss of control as the primary intervention target above ego syntonic time spent on the site.

Deceptive Intentions: Can Cues to Deception Be Measured before a Lie Is Even Stated?

PubMed Central

Ströfer, Sabine; Noordzij, Matthijs L.; Ufkes, Elze G.; Giebels, Ellen

2015-01-01

Can deceitful intentions be discriminated from truthful ones? Previous work consistently demonstrated that deceiving others is accompanied by nervousness/stress and cognitive load. Both are related to increased sympathetic nervous system (SNS) activity. We hypothesized that SNS activity already rises during intentions to lie and, consequently, cues to deception can be detected before stating an actual lie. In two experiments, controlling for prospective memory, we monitored SNS activity during lying, truth telling, and truth telling with the aim of lying at a later instance. Electrodermal activity (EDA) was used as an indicator of SNS. EDA was highest during lying, and compared to the truth condition, EDA was also raised during the intention to deceive. Moreover, the switch from truth telling toward lying in the intention condition evoked higher EDA than switching toward non-deception related tasks in the lie or truth condition. These results provide first empirical evidence that increased SNS activity related to deception can be monitored before a lie is stated. This implies that cues to deception are already present during the mere intention to lie. PMID:26018573

"Facebook depression?" social networking site use and depression in older adolescents.

PubMed

Jelenchick, Lauren A; Eickhoff, Jens C; Moreno, Megan A

2013-01-01

To evaluate the association between social networking site (SNS) use and depression in older adolescents using an experience sample method (ESM) approach. Older adolescent university students completed an online survey containing the Patient Health Questionnaire-9 depression screen (PHQ) and a week-long ESM data collection period to assess SNS use. Participants (N = 190) included in the study were 58% female and 91% Caucasian. The mean age was 18.9 years (standard deviation = .8). Most used SNSs for either <30 minutes (n = 100, 53%) or between 30 minutes and 2 hours (n = 74, 39%); a minority of participants reported daily use of SNS >2 hours (n = 16, 8%). The mean PHQ score was 5.4 (standard deviation = 4.2). No associations were seen between SNS use and either any depression (p = .519) or moderate to severe depression (p = .470). We did not find evidence supporting a relationship between SNS use and clinical depression. Counseling patients or parents regarding the risk of "Facebook Depression" may be premature. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Hybrid quantum dot-tin disulfide field-effect transistors with improved photocurrent and spectral responsivity

DOE PAGES

Cotlet, Mircea; Huang, Yuan Zang; Chen, Jia -Shiang; ...

2016-03-24

We report an improved photosensitivity in few-layer tin disulfide (SnS 2) field-effect transistors(FETs) following doping with CdSe/ZnS core/shell quantum dots(QDs). The hybrid QD-SnS 2 FET devices achieve more than 500% increase in the photocurrent response compared with the starting SnS 2-only FET device and a spectral responsivity reaching over 650 A/W at 400 nm wavelength. The negligible electrical conductance in a control QD-only FET device suggests that the energy transfer between QDs and SnS 2 is the main mechanism responsible for the sensitization effect, which is consistent with the strong spectral overlap between QDphotoluminescence and SnS 2 optical absorption asmore » well as the large nominal donor-acceptor interspacing between QD core and SnS 2. Furthermore, we also find enhanced charge carrier mobility in hybrid QD-SnS 2 FETs which we attribute to a reduced contact Schottky barrier width due to an elevated background charge carrier density.« less

Is the igeneration a 'we' generation? Social networking use among 9- to 13-year-olds and belonging.

PubMed

Quinn, Sally; Oldmeadow, Julian A

2013-03-01

Research suggests that online communication is associated with increased closeness to friends and friendship quality. Children under 13 years of age are increasingly using social networking sites (SNSs), but research with this younger age group is scarce. This study examined the relationship between SNS use and feelings of belonging among children aged 9-13 years. A self-report questionnaire was administered to 443 children (48.98% boys), asking about their SNS use and their sense of belonging to their friendship group. SNS users reported a stronger sense of belonging to their friendship group than non-users, but this was found only among older boys. Furthermore, among boy SNS users, a positive linear relationship was found between the intensity of usage and feelings of belonging. No significant relationships were found for girls. These findings suggest that boys who use these sites are gaining friendship benefits over and above those boys who are non-users or low-intensity users. Longitudinal studies should investigate the causal relationships between SNS use and social effects within this age group. © 2012 The British Psychological Society.

Impact of Social Networking Sites on Children in Military Families.

PubMed

McGuire, Austen B; Steele, Ric G

2016-09-01

Youth in military families experience a relatively unique set of stressors that can put them at risk for numerous psychological and behavior problems. Thus, there is a need to identify potential mechanisms by which children can gain resiliency against these stressors. One potential mechanism that has yet to be empirically studied with military youth is social networking sites (SNSs). SNSs have gained significant popularity among society, especially youth. Given the significance of these communication tools in youths' lives, it is important to analyze how SNS use may affect military youth and their ability to cope with common military life stressors. The current review examines the potential positive and negative consequences associated with SNS use in coping with three common stressors of youth in military families: parent deployment, frequent relocation, and having a family member with a psychological or physical disability. By drawing from SNS and military literature, we predict that SNS use can be a positive tool for helping children in military families to cope with stressors. However, certain SNS behaviors can potentially result in more negative outcomes. Recommendations for future research are also discussed.

Online social networking and the experience of cyber-bullying.

PubMed

O'Dea, Bridianne; Campbell, Andrew

2012-01-01

Online social networking sites (SNS) are popular social tools used amongst adolescents and account for much of their daily internet activity. Recently, these sites have presented opportunities for youth to experience cyber-bullying. Often resulting in psychological distress, cyber-bullying is a common experience for many young people. Continual use of SNS signifies the importance of examining its links to cyber-bullying. This study examined the relationship between online social networking and the experience of cyber-bullying. A total of 400 participants (Mage=14.31 years) completed an online survey which examined the perceived definitions and frequency of cyber-bullying. Users of SNS reported significantly higher frequencies of stranger contact compared to non-users. Spearman's rho correlations determined no significant relationship between daily time on SNS and the frequency of stranger contact. This suggests that ownership of a SNS profile may be a stronger predictor of some cyber-bullying experiences compared to time spent on these sites. Findings encourage continued research on the nature of internet activities used by young adolescents and the possible exposure to online victimization.

A model "go-kit" for use at Strategic National Stockpile Points of Dispensing.

PubMed

May, Larissa; Cote, Timothy; Hardeman, Bernard; Gonzalez, Gabriela R; Adams, Sherry B; Blair, Roderick K; Pane, Gregg

2007-01-01

The Strategic National Stockpile (SNS) is a national repository of pharmaceuticals and other medical supplies forseeably needed during a medical disaster. In the event of SNS deployment, state and local public health authorities must be prepared to receive, distribute, and dispense the materials. We propose a cache of supplies, termed the "POD go-kit," prepared in advance and locally available prior to the establishment of Points of Dispensing (POD) for SNS material. Characteristics of the preassembled go-kit are its multiplicity of use, ease of storage and transportation, minimal redundancy with SNS material, and packaging in a manner consistent with POD function. The POD go-kit is assembled into 4 separate "subkits": administrative supplies, patient routing supplies, dispensing supplies, and POD staff protection supplies. Incorporating existing practices from the SNS Listserv, this article itemizes the contents of the POD go-kit and its subkits and provides a rationale for its packaging. The Division of Strategic National Stockpile (DSNS) has not certified the proposed "POD go-kit" as a standardized POD go-kit.

Habitat-related specialization of lateral-line system morphology in a habitat-generalist and a habitat-specialist New Zealand eleotrid.

PubMed

Vanderpham, J P; Nakagawa, S; Senior, A M; Closs, G P

2016-04-01

An investigation of intraspecific habitat-related patterns of variation in oculoscapular lateral-line superficial neuromasts (SN) identified a decrease in the ratio of total SNs to pores, and a trend towards decreased asymmetry in SNs in the habitat-generalist common bully Gobiomorphus cotidianus from fluvial habitats compared to lacustrine habitats, suggesting habitat-related phenotypic variability. A greater ratio of pores to SNs, as well as less variation in the total number and asymmetry of SNs observed in the fluvial habitat-specialist redfin bully Gobiomorphus huttoni may provide further evidence of variations in the oculoscapular lateral-line morphology of fluvial habitat G. cotidianus individuals serving as adaptations to more turbulent environments. © 2016 The Fisheries Society of the British Isles.

H(-) ion source developments at the SNS.

PubMed

Welton, R F; Stockli, M P; Murray, S N; Pennisi, T R; Han, B; Kang, Y; Goulding, R H; Crisp, D W; Sparks, D O; Luciano, N P; Carmichael, J R; Carr, J

2008-02-01

The U.S. Spallation Neutron Source (SNS) will require substantially higher average and pulse H(-) beam currents than can be produced from conventional ion sources such as the base line SNS source. H(-) currents of 40-50 mA (SNS operations) and 70-100 mA (power upgrade project) with a rms emittance of 0.20-0.35pi mm mrad and a approximately 7% duty factor will be needed. We are therefore investigating several advanced ion source concepts based on rf plasma excitation. First, the performance characteristics of an external antenna source based on an Al(2)O(3) plasma chamber combined with an external multicusp magnetic configuration, an elemental Cs system, and plasma gun will be discussed. Second, the first plasma measurements of a helicon-driven H(-) ion source will also be presented.

Extending Social Networking into the Secondary Education Sector

ERIC Educational Resources Information Center

Kio, Su Iong

2016-01-01

Secondary schools do not have the same technical resources and capabilities as universities. They usually need to rely on ready-to-use tools to fulfill their information and communication technology (ICT) structure. Social networking site (SNS) has emerged as a practical solution to this need. However, few have collected empirical data on the…

Photoelectrochemical (PEC) studies on Cu2SnS3 (CTS) thin films deposited by chemical bath deposition method.

PubMed

Shelke, H D; Lokhande, A C; Kim, J H; Lokhande, C D

2017-11-15

Cu 2 SnS 3 (CTS) thin films have been successfully deposited on a cost-effective stainless steel substrate by simple and inexpensive chemical bath deposition (CBD) method. The films are deliberated in provisos of their structural, morphological, optical and photoelectrochemical (PEC) properties before and after annealing treatment, using various physico-chemical techniques. The XRD studies showed the formation of triclinic phase of CTS films with nanocrystalline structure. Also, the crystallinity is enhanced with annealing and the secondary phase of Cu 2 S observed. Raman analysis confirmed the formation of CTS compound with secondary Cu 2 S phase. The SEM images also discovered mostly tiny spherical grains and significant progress in the size of grains after annealing. The films possess direct transitions with band gap energies of 1.35eV and 1.31eV before and after annealing, respectively. The improved photoconversion efficiency of CTS thin film based PEC cell is explained with the help of theoretical modeling of energy band diagram and correspondent circuit model of the impedance spectra. Copyright © 2017 Elsevier Inc. All rights reserved.

[Influence of collagen/fibroin scaffolds containing silver nanoparticles on dermal regeneration of full-thickness skin defect wound in rat].

PubMed

You, Z G; Zhang, L P; Wang, X G; Zhou, H L; Guo, S X; Wu, P; Han, C M

2017-02-20

Objective: To explore the influence of collagen/fibroin scaffolds containing silver nanoparticles on dermal regeneration of full-thickness skin defect wound in rat. Methods: Eighty-one collagen/fibroin scaffolds containing silver nanoparticles (with the mass concentration of silver nanoparticles as 10 mg/L) and 81 collagen/fibroin scaffolds without silver nanoparticles were produced respectively with freeze-drying method and enrolled as silver nanoparticles scaffold group (SNS) and control scaffold group (CS). Nine scaffolds in each group were cultured with human fibroblasts. At post culture hour (PCH) 2, 12, and 24, the human fibroblasts adherent to the scaffolds ( n =3) in two groups were counted. Four full-thickness skin defect wounds were reproduced on the back of each one of the 36 SD rats. The rats were divided into groups SNS (wounds were transplanted with collagen/fibroin scaffolds containing silver nanoparticles) and CS (wounds were transplanted with collagen/fibroin scaffolds without silver nanoparticles) according to the random number table, with 18 rats in each group. In post surgery week (PSW) 1, 2, and 4, 6 rats in each group were sacrificed respectively for general observation, observation of histological structure, inflammatory cell infiltration, and collagen deposition with HE staining, count of CD68 positive cells with immunohistochemical staining, and mRNA expressions of interleukin-6 (IL-6) and IL-10 with real-time fluorescent quantitative reverse transcription polymerase chain reaction. Data were processed with analysis of variance of factorial design, t test, and Bonferroni correction. Results: (1) At PCH 2, 12, and 24, the numbers of human fibroblasts adherent to the scaffolds in the two groups were close (with t values from 1.77 to 2.60, P values above 0.05). (2) In PSW 1, no obvious symptom of infection was observed in wound or wound edge of rats in group SNS with obvious vascularization of scaffolds, while obvious symptoms of infection were observed in wounds of rats in group CS with some scaffolds exfoliated. In PSW 2, the scaffolds were firmly attached to the wounds of rats in group SNS, while obvious contracture was observed in the wounds of rats in group CS with a lot of scaffolds exfoliated. In PSW 4, the scaffolds covered the wounds of rats in group SNS with obvious epithelization on the surface of the scaffolds, while all the scaffolds exfoliated, leaving obvious contracture of residual wounds of rats in group CS. (3) In PSW 1 and 2, compared with those in group CS, more collagen secretion and tissue regeneration and less inflammatory cell infiltration in the scaffolds were observed in the wounds of rats in group SNS. In PSW 4, obvious epithelization was observed in the wounds of rats in group SNS, while inflammatory cell infiltration was observed without obvious epithelization in the wounds of rats in group CS. (4) In PSW 1, the number of CD68 positive cells in the wounds of rats in group SNS [(54±10) /mm(2)] was similar to that in group CS [(78±7) /mm(2,) t =1.52, P >0.05]. In PSW 2 and 4, the numbers of CD68 positive cells in the wounds of rats in group SNS [(154±10) and (77±7) /mm(2)] were significantly less than those in group CS [(268±16) and (136±13) /mm(2,) with t values respectively 7.31 and 3.83, P values below 0.01] respectively. (5) Except for the expression in PSW 4 ( t =1.23, P >0.05), the mRNA expressions of IL-6 in the wounds of rats in group SNS in PSW 1 and 2 were significantly lower than those in group CS (with t values respectively 13.12 and 4.65, P values below 0.01). Except for the expression in PSW 1 ( t =3.08, P <0.05), the mRNA expressions of IL-10 in PSW 2 and 4 in the wounds of rats in the two groups were similar (with t values respectively 2.14 and 0.49, P values above 0.05). Conclusions: Besides good biocompatibility, collagen/fibroin scaffolds containing silver nanoparticles have obvious effect in modulating inflammation, thus they can accelerate dermal regeneration induced by collagen/fibroin scaffolds for wound repair.

Noncoplanar VMAT for nasopharyngeal tumors: Plan quality versus treatment time

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wild, Esther, E-mail: e.wild@dkfz.de; Bangert, Mark; Nill, Simeon

Purpose: The authors investigated the potential of optimized noncoplanar irradiation trajectories for volumetric modulated arc therapy (VMAT) treatments of nasopharyngeal patients and studied the trade-off between treatment plan quality and delivery time in radiation therapy. Methods: For three nasopharyngeal patients, the authors generated treatment plans for nine different delivery scenarios using dedicated optimization methods. They compared these scenarios according to dose characteristics, number of beam directions, and estimated delivery times. In particular, the authors generated the following treatment plans: (1) a 4π plan, which is a not sequenced, fluence optimized plan that uses beam directions from approximately 1400 noncoplanar directionsmore » and marks a theoretical upper limit of the treatment plan quality, (2) a coplanar 2π plan with 72 coplanar beam directions as pendant to the noncoplanar 4π plan, (3) a coplanar VMAT plan, (4) a coplanar step and shoot (SnS) plan, (5) a beam angle optimized (BAO) coplanar SnS IMRT plan, (6) a noncoplanar BAO SnS plan, (7) a VMAT plan with rotated treatment couch, (8) a noncoplanar VMAT plan with an optimized great circle around the patient, and (9) a noncoplanar BAO VMAT plan with an arbitrary trajectory around the patient. Results: VMAT using optimized noncoplanar irradiation trajectories reduced the mean and maximum doses in organs at risk compared to coplanar VMAT plans by 19% on average while the target coverage remains constant. A coplanar BAO SnS plan was superior to coplanar SnS or VMAT; however, noncoplanar plans like a noncoplanar BAO SnS plan or noncoplanar VMAT yielded a better plan quality than the best coplanar 2π plan. The treatment plan quality of VMAT plans depended on the length of the trajectory. The delivery times of noncoplanar VMAT plans were estimated to be 6.5 min in average; 1.6 min longer than a coplanar plan but on average 2.8 min faster than a noncoplanar SnS plan with comparable treatment plan quality. Conclusions: The authors’ study reconfirms the dosimetric benefits of noncoplanar irradiation of nasopharyngeal tumors. Both SnS using optimized noncoplanar beam ensembles and VMAT using an optimized, arbitrary, noncoplanar trajectory enabled dose reductions in organs at risk compared to coplanar SnS and VMAT. Using great circles or simple couch rotations to implement noncoplanar VMAT, however, was not sufficient to yield meaningful improvements in treatment plan quality. The authors estimate that noncoplanar VMAT using arbitrary optimized irradiation trajectories comes at an increased delivery time compared to coplanar VMAT yet at a decreased delivery time compared to noncoplanar SnS IMRT.« less

Recurrent PAX3-MAML3 Fusion in Biphenotypic Sinonasal Sarcoma

PubMed Central

Wang, Xiaoke; Bledsoe, Krista L.; Graham, Rondell P.; Asmann, Yan W.; Viswanatha, David S.; Lewis, Jean E.; Lewis, Jason T.; Chou, Margaret M.; Yaszemski, Michael J.; Jen, Jin; Westendorf, Jennifer J.; Oliveira, André M.

2014-01-01

Biphenotypic sinonasal sarcoma (SNS) is a newly described tumor of the nasal and paranasal areas. Herein, we report the novel recurring chromosomal translocation t(2;4)(q35;q31.1) in SNS. The translocation results in the formation of the fusion protein PAX3-MAML3, which is a potent transcriptional activator of PAX3 response elements. The SNS phenotype is characterized by aberrant expression of genes involved in neuroectodermal and myogenic differentiation, which closely simulates the developmental roles of PAX3. PMID:24859338

Development of SNS Stream Analysis Based on Forest Disaster Warning Information Service System

NASA Astrophysics Data System (ADS)

Oh, J.; KIM, D.; Kang, M.; Woo, C.; Kim, D.; Seo, J.; Lee, C.; Yoon, H.; Heon, S.

2017-12-01

Forest disasters, such as landslides and wildfires, cause huge economic losses and casualties, and the cost of recovery is increasing every year. While forest disaster mitigation technologies have been focused on the development of prevention and response technologies, they are now required to evolve into evacuation and border evacuation, and to develop technologies fused with ICT. In this study, we analyze the SNS (Social Network Service) stream and implement a system to detect the message that the forest disaster occurred or the forest disaster, and search the keyword related to the forest disaster in advance in real time. It is possible to detect more accurate forest disaster messages by repeatedly learning the retrieved results using machine learning techniques. To do this, we designed and implemented a system based on Hadoop and Spark, a distributed parallel processing platform, to handle Twitter stream messages that open SNS. In order to develop the technology to notify the information of forest disaster risk, a linkage of technology such as CBS (Cell Broadcasting System) based on mobile communication, internet-based civil defense siren, SNS and the legal and institutional issues for applying these technologies are examined. And the protocol of the forest disaster warning information service system that can deliver the SNS analysis result was developed. As a result, it was possible to grasp real-time forest disaster situation by real-time big data analysis of SNS that occurred during forest disasters. In addition, we confirmed that it is possible to rapidly propagate alarm or warning according to the disaster situation by using the function of the forest disaster warning information notification service. However, the limitation of system application due to the restriction of opening and sharing of SNS data currently in service and the disclosure of personal information remains a problem to be solved in the future. Keyword : SNS stream, Big data, Machine learning techniques, CBS, Forest disaster warning information service system Acknowledgement : This research was supported by the Forestry Technology 2015 Forestry Technology Research and Development Project (Planning project).

Microwave assisted synthesis of porous ZnO/SnS heterojunction and its application in visible light degradation of ciprofloxacin

NASA Astrophysics Data System (ADS)

Makama, A. B.; Salmiaton, A.; Saion, E. B.; Choong, T. S. Y.; Abdullah, N.

2016-07-01

Porous ZnO/SnS heterojunctions were successfully synthesized via microwave-assisted heating of aqueous solutions containing different amounts of SnS precursors (SnCl2 and Na2S) in the presence of fixed amount of ZnCO3 nanoparticles. The experimental results revealed that the heterojunctions exhibited much higher visible light-driven photocatalytic activity for the degradation of the ciprofloxacin than pure SnS nanocrystals. The photocatalytic degradation efficiency (1-Ct/C0) of the pollutant for the most active heterogeneous nanostructure is about four times more efficient than pure SnS. The enhanced photocatalytic efficiency is ascribed to the synergic effect of high photon absorption and reduction in the recombination of electrons and holes because of efficient separation and electron transfer from the SnS to ZnO nanoparticles.

The independent relationship between trouble controlling Facebook use, time spent on the site and distress

PubMed Central

Muench, Fredrick; Hayes, Marie; Kuerbis, Alexis; Shao, Sijing

2015-01-01

Background and Aims There is an emerging literature base on the relationship between maladaptive traits and “addiction” to social networking sites. These studies have operationalized addiction as either spending excessive amounts of time on social networking sites (SNS) or trouble controlling SNS use, but have not assessed the unique contribution of each of these constructs on outcomes in the same models. Moreover, these studies have exclusively been conducted with younger people rather than a heterogeneous sample. This study examined the independent relationship of a brief Facebook addiction scale, time spent on Facebook, and Facebook checking on positive and negative social domains, while controlling for self-esteem and social desirability. Methods Participants were recruited using e-mail, SNS posts and through Amazon’s MTurk system. The sample included 489 respondents ages from 18 to approximately 70, who completed a 10–15 minute survey. Results Results indicate that neither time spent on Facebook nor Facebook checking was significantly associated with either self-esteem, fear of negative social evaluation or social comparison, while SNS addiction symptoms were each independently associated with Facebook usage. Neither time spent on Facebook nor SNS addiction symptoms were associated with positive social relationships. Discussion Overall results suggest that time on SNS and trouble controlling use should be considered independent constructs and that interventions should target underlying loss of control as the primary intervention target above ego syntonic time spent on the site. PMID:26551906

The use of social networking sites: A risk factor for using alcohol, marijuana, and synthetic cannabinoids?

PubMed

Gutierrez, Kevin M; Cooper, Theodore V

2016-06-01

The use of social networking sites (SNS) has become a central aspect of youth culture allowing individuals to explore and assert their identities. A commonly portrayed online identity is an "alcohol identity," and past research suggests such identities may contribute to one's risk of using alcohol. The present study builds on past research by examining the relationship between alcohol, marijuana, and synthetic cannabinoid use (e.g., Spice, K2) and time spent on SNS in a sample of college students. Six hundred ninety nine undergraduates (62.4% female; Mage=21.0, SD=8.56) were recruited from a university on the U.S./Mexico border for an online study. Participants completed measures assessing demographics, substance use history, and amount of time spent on SNS. Participants reported spending 46h per month on SNS. Seventy-one percent, 14%, and 3% of the sample reported past month use of alcohol, marijuana, and synthetic cannabinoids, respectively. Regression analyses revealed that hours spent on SNS in the past month were significantly associated with frequency of alcohol (p<0.001) and synthetic cannabinoid use (p<0.001). In addition, being male was associated with frequency of alcohol and marijuana use in the past month (p<0.001 and p<0.001, respectively). These findings suggest that assessment of time spent on SNS is warranted in studies investigating drug use among college students. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Comparing farmers' market revenue trends before and after the implementation of a monetary incentive for recipients of food assistance.

PubMed

Freedman, Darcy A; Mattison-Faye, Amy; Alia, Kassandra; Guest, M Aaron; Hébert, James R

2014-05-22

We examined the influence of an intervention to increase fruit and vegetable purchases at farmers' markets for recipients of food assistance, Shop N Save (SNS), on revenue trends at a farmers' market located at a federally qualified health center (FQHC) in rural South Carolina. We compared revenue trends for 20 weeks before the intervention (2011) and 20 weeks after (2012). SNS provided one $5 monetary incentive per week to customers spending $5 or more in food assistance at the farmers' market. SNS was available to any farmers' market customer using Supplemental Nutrition Assistance Program (SNAP), Special Supplemental Nutrition Program for Women, Infants, and Children (WIC), and/or Senior or WIC Farmers' Market Nutrition Program (FMNP) vouchers. Sales receipts were recorded for each transaction at the farmers' market to document payment type and the cost of the purchase. All SNS participants completed a one-time enrollment survey. A total of 336 customers self-enrolled in SNS from June through October 2012. Most SNS participants were female, African American, and patients at the FQHC. In total, the use of all forms of food assistance (SNAP, WIC, and FMNP) at the farmers' market increased significantly after the intervention (from 10% before, to 25% after, P = .003). Senior FMNP vouchers and SNAP usage increased the most. Interventions that provide incentives to recipients of food assistance programs at farmers' markets are a viable strategy for increasing food assistance usage and revenue.

The unpredictability of lymphatic drainage from the ear in melanoma patients, and its implications for management.

PubMed

Peach, Howard S; van der Ploeg, Augustinus P T; Haydu, Lauren E; Stretch, Jonathan R; Shannon, Kerwin F; Uren, Roger F; Thompson, John F

2013-05-01

The ear is known to have variable lymphatic drainage. The purpose of this study was to define better the lymphatic drainage patterns of the ear by correlating the location of primary tumors, classified according to the embryologically derived anatomical subunits of the ear, with their mapped sentinel nodes (SNs) identified by lymphoscintigraphy (LS). Lymphatic drainage data for patients with a primary melanoma of the ear were reviewed and correlated with the precise primary melanoma site. Between 1993 and 2010, LS was performed in 111 patients with a primary melanoma on the ear, identifying 281 SNs in 195 lymph node (LN) fields. The mean numbers of SNs and LN fields identified by LS per patient were 2.65 and 1.76. SN biopsy was performed in 71 patients (64 %). The mean number of SNs removed was 2.36. The 111 ear melanomas were mostly located on the helical rim (55 %), followed by the lobule (24.3 %). The five different primary ear sites drained mainly to SNs in level CII, level CV and the preauricular region. Drainage was most often to level CII (36.4 %). Drainage to the contralateral neck was not observed. Lymphatic drainage of the ear has no predictable pattern and can be to SNs anywhere in the ipsilateral neck. Most commonly drainage is to cervical level II and the preauricular and postauricular LN fields. LS defines the lymphatic drainage pattern in individual melanoma patients and is essential for accurate SN identification and reliable SN biopsy.

Lessons learned from use of social network strategy in HIV testing programs targeting African American men who have sex with men.

PubMed

McCree, Donna H; Millett, Gregorio; Baytop, Chanza; Royal, Scott; Ellen, Jonathan; Halkitis, Perry N; Kupprat, Sandra A; Gillen, Sara

2013-10-01

We report lessons derived from implementation of the Social Network Strategy (SNS) into existing HIV counseling, testing, and referral services targeting 18- to 64-year-old Black gay, bisexual, and other men who have sex with men (MSM). The SNS procedures used in this study were adapted from a Centers for Disease Control and Prevention-funded, 2-year demonstration project involving 9 community-based organizations (CBOs) in 7 cities. Under the SNS, HIV-positive and HIV-negative men at high risk for HIV (recruiters) were enlisted to identify and recruit persons from their social, sexual, or drug-using networks (network associates) for HIV testing. Sites maintained records of modified study protocols for ascertaining lessons learned. The study was conducted between April 2008 and May 2010 at CBOs in Washington, DC, and New York, New York, and at a health department in Baltimore, Maryland. Several common lessons regarding development of the plan, staffing, training, and use of incentives were identified across the sites. Collectively, these lessons indicate use of SNS is resource-intensive, requiring a detailed plan, dedicated staff, and continual input from clients and staff for successful implementation. SNS may provide a strategy for identifying and targeting clusters of high-risk Black MSM for HIV testing. Given the resources needed to implement the strategy, additional studies using an experimental design are needed to determine the cost-effectiveness of SNS compared with other testing strategies.

Comparing Farmers’ Market Revenue Trends Before and After the Implementation of a Monetary Incentive for Recipients of Food Assistance

PubMed Central

Mattison-Faye, Amy; Alia, Kassandra; Guest, M. Aaron; Hébert, James R.

2014-01-01

Introduction We examined the influence of an intervention to increase fruit and vegetable purchases at farmers’ markets for recipients of food assistance, Shop N Save (SNS), on revenue trends at a farmers’ market located at a federally qualified health center (FQHC) in rural South Carolina. We compared revenue trends for 20 weeks before the intervention (2011) and 20 weeks after (2012). Methods SNS provided one $5 monetary incentive per week to customers spending $5 or more in food assistance at the farmers’ market. SNS was available to any farmers’ market customer using Supplemental Nutrition Assistance Program (SNAP), Special Supplemental Nutrition Program for Women, Infants, and Children (WIC), and/or Senior or WIC Farmers’ Market Nutrition Program (FMNP) vouchers. Sales receipts were recorded for each transaction at the farmers’ market to document payment type and the cost of the purchase. All SNS participants completed a one-time enrollment survey. Results A total of 336 customers self-enrolled in SNS from June through October 2012. Most SNS participants were female, African American, and patients at the FQHC. In total, the use of all forms of food assistance (SNAP, WIC, and FMNP) at the farmers’ market increased significantly after the intervention (from 10% before, to 25% after, P = .003). Senior FMNP vouchers and SNAP usage increased the most. Conclusion Interventions that provide incentives to recipients of food assistance programs at farmers’ markets are a viable strategy for increasing food assistance usage and revenue. PMID:24854238

Problematic use of social network sites: the interactive relationship between gratifications sought and privacy concerns.

PubMed

Chen, Hsuan-Ting; Kim, Yonghwan

2013-11-01

Problematic Internet use has long been a matter of concern; however, few studies extend this line of research from general Internet use to the use of social network sites (SNSs), or explicate the problematic use of SNSs by understanding what factors may enhance or reduce users' compulsive behaviors and excessive form of use on SNSs. Building on literature that found a positive relationship between gratifications sought from the Internet and problematic Internet use, this study first explores the types of gratifications sought from SNSs and examines their relationship with problematic SNS use. It found that three types of gratifications-diversion, self-presentation, and relationship building-were positively related to problematic SNS use. In addition, with a growing body of research on SNS privacy, a moderating role of privacy concerns on SNSs has been proposed to understand how it can influence the relationship between gratifications sought from SNSs and problematic SNS use. The findings suggest that different subdimensions of privacy concerns interact with gratifications sought in different manners. In other words, privacy concerns, including unauthorized secondary use and improper access, play a more influential role in constraining the positive relationship between gratifications sought and problematic SNS use when individuals seek to build relationships on SNSs. However, if individuals seek to have diversion on SNSs, their privacy concerns will be overridden by their gratifications sought, which in turn leads to problematic SNS use. Implications of these findings for future research are discussed.

Interests diffusion on a semantic multiplex. Comparing Computer Science and American Physical Society communities

NASA Astrophysics Data System (ADS)

D'Agostino, Gregorio; De Nicola, Antonio

2016-10-01

Exploiting the information about members of a Social Network (SN) represents one of the most attractive and dwelling subjects for both academic and applied scientists. The community of Complexity Science and especially those researchers working on multiplex social systems are devoting increasing efforts to outline general laws, models, and theories, to the purpose of predicting emergent phenomena in SN's (e.g. success of a product). On the other side the semantic web community aims at engineering a new generation of advanced services tailored to specific people needs. This implies defining constructs, models and methods for handling the semantic layer of SNs. We combined models and techniques from both the former fields to provide a hybrid approach to understand a basic (yet complex) phenomenon: the propagation of individual interests along the social networks. Since information may move along different social networks, one should take into account a multiplex structure. Therefore we introduced the notion of "Semantic Multiplex". In this paper we analyse two different semantic social networks represented by authors publishing in the Computer Science and those in the American Physical Society Journals. The comparison allows to outline common and specific features.

Quasiparticle band structures and interface physics of SnS and GeS

NASA Astrophysics Data System (ADS)

Malone, Brad; Kaxiras, Efthimios

2013-03-01

Orthorhombic SnS and GeS are layered materials made of earth-abundant elements which have the potential to play a useful role in the massive scale up of renewable power necessary by 2050 to avoid unmanageable levels of climate change. We report on first principles calculations of the quasiparticle spectra of these two materials, predicting the type and magnitude of the fundamental band gap, a quantity which shows a strong degree of scatter in the experimental literature. Additionally, in order to evaluate the possible role of GeS as an electron-blocking layer in a SnS-based photovoltaic device, we investigate the band offsets of the interfaces between these materials along the three principle crystallographic directions. We find that while the valence-band offsets are similar along the three principle directions, the conduction-band offsets display a substantial amount of anisotropy.

Eco-friendly p-type Cu2SnS3 thermoelectric material: crystal structure and transport properties

PubMed Central

Shen, Yawei; Li, Chao; Huang, Rong; Tian, Ruoming; Ye, Yang; Pan, Lin; Koumoto, Kunihito; Zhang, Ruizhi; Wan, Chunlei; Wang, Yifeng

2016-01-01

As a new eco-friendly thermoelectric material, copper tin sulfide (Cu2SnS3) ceramics were experimentally studied by Zn-doping. Excellent electrical transport properties were obtained by virtue of 3-dimensionally conductive network for holes, which are less affected by the coexistence of cubic and tetragonal phases that formed upon Zn subsitition for Sn; a highest power factors ~0.84 mW m−1 K−2 at 723 K was achieved in the 20% doped sample. Moreover, an ultralow lattice thermal conductivity close to theoretical minimum was observed in these samples, which could be related to the disordering of atoms in the coexisting cubic and tetragonal phases and the interfaces. Thanks to the phonon-glass-electron-crystal features, a maximum ZT ~ 0.58 was obtained at 723 K, which stands among the tops for sulfide thermoelectrics at the same temperature. PMID:27666524

Chasing The 'Like': Adolescent Use Of Social Networking Sites In Australia.

PubMed

la Sala, Louise; Skues, Jason; Wise, Lisa; Theiler, Stephen

2015-01-01

The current study investigated how adolescents behave on Social Networking Sites (SNSs) and how they interpret the feedback they receive online from others. Thirty-four Australian adolescents (26 girls, 8 boys) aged 13 to 17 years participated in the study. Five semi-structured focus groups (3 mixed groups, 2 all-girl groups) were conducted to explore how adolescents perceive their own and others' SNS behaviours, the motivation underlying these behaviours, and the expected outcomes related to particular behaviours. Teenagers reported that they spend a good deal of time planning their SNS posts, felt that the information they posted was a true reflection of them as a person, and thus interpreted feedback ("likes") as measuring their self-worth. In contrast, some teenagers were perceived as "chasing the like" for status and popularity while not caring about how accurately their posts represented them as a person. A potential gender bias in these findings is discussed.

Social Networking Sites and Addiction: Ten Lessons Learned

PubMed Central

Kuss, Daria J.; Griffiths, Mark D.

2017-01-01

Online social networking sites (SNSs) have gained increasing popularity in the last decade, with individuals engaging in SNSs to connect with others who share similar interests. The perceived need to be online may result in compulsive use of SNSs, which in extreme cases may result in symptoms and consequences traditionally associated with substance-related addictions. In order to present new insights into online social networking and addiction, in this paper, 10 lessons learned concerning online social networking sites and addiction based on the insights derived from recent empirical research will be presented. These are: (i) social networking and social media use are not the same; (ii) social networking is eclectic; (iii) social networking is a way of being; (iv) individuals can become addicted to using social networking sites; (v) Facebook addiction is only one example of SNS addiction; (vi) fear of missing out (FOMO) may be part of SNS addiction; (vii) smartphone addiction may be part of SNS addiction; (viii) nomophobia may be part of SNS addiction; (ix) there are sociodemographic differences in SNS addiction; and (x) there are methodological problems with research to date. These are discussed in turn. Recommendations for research and clinical applications are provided. PMID:28304359

Social Networking Sites and Addiction: Ten Lessons Learned.

PubMed

Kuss, Daria J; Griffiths, Mark D

2017-03-17

Online social networking sites (SNSs) have gained increasing popularity in the last decade, with individuals engaging in SNSs to connect with others who share similar interests. The perceived need to be online may result in compulsive use of SNSs, which in extreme cases may result in symptoms and consequences traditionally associated with substance-related addictions. In order to present new insights into online social networking and addiction, in this paper, 10 lessons learned concerning online social networking sites and addiction based on the insights derived from recent empirical research will be presented. These are: (i) social networking and social media use are not the same; (ii) social networking is eclectic; (iii) social networking is a way of being; (iv) individuals can become addicted to using social networking sites; (v) Facebook addiction is only one example of SNS addiction; (vi) fear of missing out (FOMO) may be part of SNS addiction; (vii) smartphone addiction may be part of SNS addiction; (viii) nomophobia may be part of SNS addiction; (ix) there are sociodemographic differences in SNS addiction; and (x) there are methodological problems with research to date. These are discussed in turn. Recommendations for research and clinical applications are provided.

Sympathetic overactivity in hypertension and cardiovascular disease.

PubMed

Manolis, A J; Poulimenos, L E; Kallistratos, M S; Gavras, I; Gavras, H

2014-01-01

From the first description of its anatomy by T. Willis to the novel therapeutic manipulations, it is unanimously recognized that the sympathetic nervous system (SNS) holds a crucial role in cardiovascular homeostasis. The introduction of sophisticated techniques, as microneurography and regional norepinephrine spillover provided the evidence for the role of sympathetic overactivity in various cardiovascular disease entities. Sympathetic activation is common in patients with essential hypertension and contributes to initiation, maintenance and progression of the disease and it contributes to the manifestation of its major complications. A considerable body of evidence relates SNS overactivity with high sodium intake in experimental animals and humans and the underlying mechanisms have nowadays been elucidated. SNS activity is more pronounced in patients with resistant hypertension and there are several conditions that lead to this phenomenon, as older age, kidney disease, obesity and metabolic syndrome, mental stress and sleep apnea. SNS overactivity holds also a key physiopathological role in heart failure, acute coronary syndromes and arrhythmias. Moreover, inhibition of sympathetic overactivity by various means, including central SNS suppressing drugs, peripheral alpha- and beta- adrenergic receptor blockers, or novel approaches as renal sympathetic denervation have been used successfully in the treatment of all these disorders.

Exploring the predicted effect of social networking site use on perceived social capital and psychological well-being of Chinese international students in Japan.

PubMed

Guo, Yu; Li, Yiwei; Ito, Naoya

2014-01-01

This study investigated how social networking sites (SNSs) use by Chinese international students in Japan influenced their perceived social capital and psychological well-being. In addition, it examined how, as sojourners, Chinese international students' perceived acculturative stress varied. Data were collected from 142 Chinese international students. The results indicated that the intensity of SNS use was unable to predict individuals' perceived social capital and psychological well-being. The effect of SNS use varied according to the functions it serves. Specifically, SNS use for social and informational functions (SIF) increased individuals' levels of perceived bridging social capital and perceived life satisfaction, while SNS use for entertaining recreational functions (ERF) was unable to predict perceived social capital but increased individuals' levels of loneliness. It was also found that, in the intercultural environment, Chinese international students' levels of perceived acculturative stress were decreased by their perceived bonding social capital and increased by their perceived loneliness but had no relationship with their SNS use. Findings of the study suggest that individuals using SNSs to stay informed and connected will benefit with regard to their social network building and psychological well-being.

One-step solvothermal synthesis of carnation flower-like SnS2 as superior electrodes for supercapacitor applications

NASA Astrophysics Data System (ADS)

Mishra, Rajneesh Kumar; Baek, Geun Woo; Kim, Kyuwon; Kwon, Hyuck-In; Jin, Sung Hun

2017-12-01

We report the synthesis of carnation flower-like SnS2 (CF-SnS2) via a one-step solvothermal method for potential application as supercapacitor electrodes in energy storage devices. The structural and morphological properties of CF-SnS2 were characterized by X-ray diffraction, Raman analysis, and field-emission scanning and transmission electron microscopies. X-ray photoelectron spectroscopy and scanning tunneling electron microscopy with color mapping verified the distribution of Sn and S, and depicted the successful formation of SnS2. Electrochemical studies were performed to explore the supercapacitive nature of CF-SnS2. Supercapacitors with CF-SnS2 electrodes delivered excellent cyclic voltammetry performances, superior gravimetric specific capacitances, and high power densities. The evaluated specific capacitance and power density reached ∼524.5 F/g and 12.3 W/kg, respectively, at a current density of 0.08 A/g, and ∼215.9 F/g and 61.4 W/kg, respectively, at a current density of 0.38 A/g. These values are at least two times higher than those previously reported. The long-term cyclic stability was also tested to demonstrate the endurance of the CF-SnS2-based supercapacitor, with a 66% rate retention and galvanostatic charge/discharge reversibility. These electrochemical findings indicate that CF-SnS2 is a promising candidate for electrode materials in supercapacitor applications.

Strategic Self-Presentation or Authentic Communication? Predicting Adolescents' Alcohol References on Social Media.

PubMed

Geusens, Femke; Beullens, Kathleen

2017-01-01

The current study is one of the first to examine how self-reported alcohol consumption, friends' perceived alcohol consumption, and the perceived number of friends sharing alcohol references on social networking sites (SNS) is associated with adolescents' sharing of alcohol references on SNS. A cross-sectional paper-and-pencil survey was administered among 3,172 adolescents (n = 3,133 used for analyses, mean age = 17.16 years, SD = 0.93; 50.7% male). Structural equation modeling was used to test the hypotheses. First, the results indicated that both self-reported drinking behavior and the perceived number of friends sharing alcohol references were related to sharing alcohol references on SNS, but the perceived number of friends sharing alcohol references was a stronger predictor than self-reported drinking behavior. Friends' perceived drinking behavior was not a significant predictor. In the second place, self-reported drinking behavior was a stronger predictor for girls than for boys, whereas the perceived number of friends sharing alcohol references was a stronger predictor for boys than for girls. Adolescents' alcohol-related self-representation is in line with their alcohol consumption and is also strongly related to what their friends are sharing. Thus, adolescents appear to communicate authentically about their drinking experiences, but the decision to do so is heavily influenced by the prevailing social norm regarding alcohol-related communication.

Shielding and Activation Analyses for BTF Facility at SNS

NASA Astrophysics Data System (ADS)

Popova, Irina; Gallmeier, Franz X.

2017-09-01

The beam test facility (BTF), which simulates front end of the Spallation Neutron Source (SNS), has been built at the SNS, and is preparing for commissioning. The BTF has been assembled and will operate in one of service buildings at the site. The 2.5 MeV proton beam, produced in the facility, will be stopped in the beam dump. In order to support BTF project from radiation protection site, neutronics simulations and activation analyses were performed to evaluate the necessary shielding around the facility and radionuclide inventory of the beam stop.

Occurrence of Multiple Subsequent Neoplasms in Long-Term Survivors of Childhood Cancer: A Report From the Childhood Cancer Survivor Study

PubMed Central

Armstrong, Gregory T.; Liu, Wei; Leisenring, Wendy; Yasui, Yutaka; Hammond, Sue; Bhatia, Smita; Neglia, Joseph P.; Stovall, Marilyn; Srivastava, Deokumar; Robison, Leslie L.

2011-01-01

Purpose Childhood cancer survivors experience an increased incidence of subsequent neoplasms (SNs). Those surviving the first SN (SN1) remain at risk to develop multiple SNs. Because SNs are a common cause of late morbidity and mortality, characterization of rates of multiple SNs is needed. Patients and Methods In a total of 14,358 5-year survivors of childhood cancer diagnosed between 1970 and 1986, analyses were carried out among 1,382 survivors with an SN1. Cumulative incidence of second subsequent neoplasm (SN2), either malignant or benign, was calculated. Results A total of 1,382 survivors (9.6%) developed SN1, of whom 386 (27.9%) developed SN2. Of those with SN2, 153 (39.6%) developed more than two SNs. Cumulative incidence of SN2 was 46.9% (95% CI, 41.6% to 52.2%) at 20 years after SN1. The cumulative incidence of SN2 among radiation-exposed survivors was 41.3% (95% CI, 37.2% to 45.4%) at 15 years compared with 25.7% (95% CI, 16.5% to 34.9%) for those not treated with radiation. Radiation-exposed survivors who developed an SN1 of nonmelanoma skin cancer (NMSC) had a cumulative incidence of subsequent malignant neoplasm (SMN; ie, malignancies excluding NMSC) of 20.3% (95% CI, 13.0% to 27.6%) at 15 years compared with only 10.7% (95% CI, 7.2% to 14.2%) for those who were exposed to radiation and whose SN1 was an invasive SMN (excluding NMSC). Conclusion Multiple SNs are common among aging survivors of childhood cancer. SN1 of NMSC identifies a population at high risk for invasive SMN. Survivors not exposed to radiation who develop multiple SNs represent a population of interest for studying genetic susceptibility to neoplasia. PMID:21709189

Narrow-gap physical vapour deposition synthesis of ultrathin SnS1-xSex (0 ≤ x ≤ 1) two-dimensional alloys with unique polarized Raman spectra and high (opto)electronic properties.

PubMed

Gao, Wei; Li, Yongtao; Guo, Jianhua; Ni, Muxun; Liao, Ming; Mo, Haojie; Li, Jingbo

2018-05-10

Here we report ultrathin SnS1-xSex alloyed nanosheets synthesized via a narrow-gap physical vapour deposition approach. The SnS1-xSex alloy presents a uniform quadrangle shape with a lateral size of 5-80 μm and a thickness of several nanometers. Clear orthorhombic symmetries and unique in-plane anisotropic properties of the 2D alloyed nanosheets were found with the help of X-ray diffraction, high resolution transmission electron microscopy and polarized Raman spectroscopy. Moreover, 2D alloyed field-effect transistors were fabricated, exhibiting a unipolar p-type semiconductor behavior. This study also provided a lesson that the thickness of the alloyed channels played the major role in the current on/off ratio, and the high ratio of 2.10 × 102 measured from a large ultrathin SnS1-xSex device was two orders of magnitude larger than that of previously reported SnS, SnSe nanosheet based transistors because of the capacitance shielding effect. Obviously enhanced Raman peaks were also found in the thinner nanosheets. Furthermore, the ultrathin SnS0.5Se0.5 based photodetector showed a highest responsivity of 1.69 A W-1 and a short response time of 40 ms under illumination of a 532 nm laser from 405 to 808 nm. Simultaneously, the corresponding highest external quantum efficiency of 392% and detectivity of 3.96 × 104 Jones were also achieved. Hopefully, the narrow-gap synthesis technique provides us with an improved strategy to obtain large ultrathin 2D nanosheets which may tend to grow into thicker ones for stronger interlayer van der Waals forces, and the enhanced physical and (opto)electrical performances in the obtained ultrathin SnS1-xSex alloyed nanosheets prove their great potential in the future applications for versatile devices.

Subsequent neoplasms in survivors of childhood central nervous system tumors: risk after modern multimodal therapy.

PubMed

Tsui, Karen; Gajjar, Amar; Li, Chenghong; Srivastava, Deokumar; Broniscer, Alberto; Wetmore, Cynthia; Kun, Larry E; Merchant, Thomas E; Ellison, David W; Orr, Brent A; Boop, Frederick A; Klimo, Paul; Ross, Jordan; Robison, Leslie L; Armstrong, Gregory T

2015-03-01

Multimodal therapy has improved survival for some childhood CNS tumors. However, whether risk for subsequent neoplasms (SNs) also increases is unknown. We report the cumulative incidence of, and risk factors for, SNs after a childhood primary CNS tumor and determine whether treatment that combines radiation therapy (RT) with chemotherapy increases risk for SNs. Analyses included 2779 patients with a primary CNS tumor treated at St Jude Children's Research Hospital between 1985 and 2012. Cumulative incidence and standardized incidence ratios (SIRs) were estimated for SNs confirmed by pathology report. Cumulative incidence among the 237 five-year medulloblastoma survivors treated with multimodal therapy (RT + chemotherapy) was compared with a historical cohort of 139 five-year survivors treated with RT but no chemotherapy in the Childhood Cancer Survivor Study. Eighty-one survivors had 97 SNs. The cumulative incidence of first SN was 3.0% (95% CI: 2.3%-3.9%) at 10 years, and 6.0% (95% CI: 4.6%-7.7%) at 20 years from diagnosis. Risks were highest for subsequent glioma, all grades (SIR = 57.2; 95% CI: 36.2-85.8) and acute myeloid leukemia (SIR = 31.8; 95% CI: 10.2-74.1). Compared with RT alone, RT + chemotherapy did not increase risk for SNs (hazard ratio: 0.64; 95% CI: 0.38-1.06). Among five-year survivors of medulloblastoma treated with multimodal therapy, cumulative incidence of SN was 12.0% (95% CI: 6.4%-19.5%) at 20 years, no different than survivors treated with RT alone (11.3%, P = .44). The cumulative incidence of SNs continues to increase with time from treatment with no obvious plateau, but the risk does not appear to be higher after exposure to multimodal therapy compared with RT alone. Continued follow-up of survivors as they age is essential. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The influence of social networking sites on health behavior change: a systematic review and meta-analysis.

PubMed

Laranjo, Liliana; Arguel, Amaël; Neves, Ana L; Gallagher, Aideen M; Kaplan, Ruth; Mortimer, Nathan; Mendes, Guilherme A; Lau, Annie Y S

2015-01-01

Our aim was to evaluate the use and effectiveness of interventions using social networking sites (SNSs) to change health behaviors. Five databases were scanned using a predefined search strategy. Studies were included if they focused on patients/consumers, involved an SNS intervention, had an outcome related to health behavior change, and were prospective. Studies were screened by independent investigators, and assessed using Cochrane's 'risk of bias' tool. Randomized controlled trials were pooled in a meta-analysis. The database search retrieved 4656 citations; 12 studies (7411 participants) met the inclusion criteria. Facebook was the most utilized SNS, followed by health-specific SNSs, and Twitter. Eight randomized controlled trials were combined in a meta-analysis. A positive effect of SNS interventions on health behavior outcomes was found (Hedges' g 0.24; 95% CI 0.04 to 0.43). There was considerable heterogeneity (I(2) = 84.0%; T(2) = 0.058) and no evidence of publication bias. To the best of our knowledge, this is the first meta-analysis evaluating the effectiveness of SNS interventions in changing health-related behaviors. Most studies evaluated multi-component interventions, posing problems in isolating the specific effect of the SNS. Health behavior change theories were seldom mentioned in the included articles, but two particularly innovative studies used 'network alteration', showing a positive effect. Overall, SNS interventions appeared to be effective in promoting changes in health-related behaviors, and further research regarding the application of these promising tools is warranted. Our study showed a positive effect of SNS interventions on health behavior-related outcomes, but there was considerable heterogeneity. Protocol registration The protocol for this systematic review is registered at http://www.crd.york.ac.uk/PROSPERO with the number CRD42013004140. © The Author 2014. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.comFor numbered affiliations see end of article.

Wild Band Edges: The Role of Bandgap Grading and Band-Edge Fluctuations in High-Efficiency Chalcogenide Devices: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Repins, Ingrid; Mansfield, Lorelle; Kanevce, Ana

Band-edge effects -- including grading, electrostatic fluctuations, bandgap fluctuations, and band tails -- affect chalcogenide device efficiency. These effects now require more careful consideration as efficiencies increase beyond 20%. Several aspects of the relationships between band-edge phenomena and device performance for NREL absorbers are examined. For Cu(In,Ga)Se2 devices, recent increases in diffusion length imply changes to optimum bandgap profile. The origin, impact, and modification of electrostatic and bandgap fluctuations are also discussed. The application of the same principles to devices based on CdTe, kesterites, and emerging absorbers (Cu2SnS3, CuSbS2), considering differences in materials properties and defect formation energies, is examined.

Online Social Networking and Mental Health

PubMed Central

2014-01-01

Abstract During the past decade, online social networking has caused profound changes in the way people communicate and interact. It is unclear, however, whether some of these changes may affect certain normal aspects of human behavior and cause psychiatric disorders. Several studies have indicated that the prolonged use of social networking sites (SNS), such as Facebook, may be related to signs and symptoms of depression. In addition, some authors have indicated that certain SNS activities might be associated with low self-esteem, especially in children and adolescents. Other studies have presented opposite results in terms of positive impact of social networking on self-esteem. The relationship between SNS use and mental problems to this day remains controversial, and research on this issue is faced with numerous challenges. This concise review focuses on the recent findings regarding the suggested connection between SNS and mental health issues such as depressive symptoms, changes in self-esteem, and Internet addiction. PMID:25192305

Snaps, Selfies, and Shares: How Three Popular Social Media Platforms Contribute to the Sociocultural Model of Disordered Eating Among Young Women.

PubMed

Saunders, Jessica F; Eaton, Asia A

2018-06-01

The current study aimed to integrate and test the sociocultural model of disordered eating with theories explaining the impact of mass media on the development of disordered eating for users of three popular social networking platforms. Young women social networking site (SNS) users (age 18-24) who had never received an eating disorder diagnosis (N = 637) completed questions capturing their SNS gratifications and usage, body surveillance, social comparisons, body dissatisfaction, and eating pathology. Measures were administered in one online session. Model relationships were similar across users of all three SNS platforms: Facebook, Instagram, and Snapchat. Users of all platforms demonstrated a significant positive relationship between upward comparisons and disordered eating outcomes, and between body surveillance and disordered eating outcomes, although differences between models did emerge. Empirical findings support extending the sociocultural model of disordered eating to include SNS uses and gratifications.

The use of social networking services and their relationship with the big five personality model and job satisfaction in Korea.

PubMed

Kim, Hyondong; Chung, Yang Woon

2014-10-01

Social networking services (SNSs) have been garnering attention from society due to their recent rapid growth. This study examines whether SNS use can affect the relationship between the Big Five personality model and individual job satisfaction. Based on a sample of 1,452 workers in Korea, the results of this study indicate that the Big Five personality model (extroversion, agreeableness, and neuroticism) was significantly related to individual job satisfaction. Further, SNS use moderated the relationship between extroversion and neuroticism with individual job satisfaction. Also, SNS use was found to increase job satisfaction of Korean workers who are more extroverted, while it also affected job satisfaction of Korean workers with low agreeableness. As SNS use plays an important role in the workplace, it is necessary to realize and appreciate the importance of SNSs in shaping and promoting job satisfaction of working individuals.

Social networking sites: a clinical dilemma?

PubMed

Maughan, Daniel Lawrence; Economou, Alexis

2015-02-01

Social networking sites (SNS) are having an increasing influence on patients' lives and doctors are far from certain about how to deal with this new challenge. In our literature search, we could find no research on how doctors could engage positively with SNS to improve patient outcomes or create more patient-led care. We need to acknowledge the fact that a review of a patient's SNS page has the potential to enhance assessment and management, particularly where a corroborant history is hard to attain. As doctors, we need to think clearly about how to adapt our practice in light of this new form of communication; in particular, whether there is a case for engaging with SNS to improve patient care. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Online social networking and mental health.

PubMed

Pantic, Igor

2014-10-01

During the past decade, online social networking has caused profound changes in the way people communicate and interact. It is unclear, however, whether some of these changes may affect certain normal aspects of human behavior and cause psychiatric disorders. Several studies have indicated that the prolonged use of social networking sites (SNS), such as Facebook, may be related to signs and symptoms of depression. In addition, some authors have indicated that certain SNS activities might be associated with low self-esteem, especially in children and adolescents. Other studies have presented opposite results in terms of positive impact of social networking on self-esteem. The relationship between SNS use and mental problems to this day remains controversial, and research on this issue is faced with numerous challenges. This concise review focuses on the recent findings regarding the suggested connection between SNS and mental health issues such as depressive symptoms, changes in self-esteem, and Internet addiction.

Enhancement of photoelectrochemical activity of SnS thin-film photoelectrodes using TiO2, Nb2O5, and Ta2O5 metal oxide layers

NASA Astrophysics Data System (ADS)

Vequizo, Junie Jhon M.; Yokoyama, Masanori; Ichimura, Masaya; Yamakata, Akira

2016-06-01

Tin sulfide (SnS) fine photoelectrodes fabricated by three-step pulsed electrodeposition were active for H2 evolution. The incident-photon-conversion-efficiency increases from 900 nm and offers a good fit with the absorption spectrum. The activity was enhanced by 3.4, 3.0, and 1.8 times compared to bare SnS by loading Nb2O5, TiO2, and Ta2O5, respectively. Nb2O5 was most efficient because its conduction band is low enough to facilitate effective electron transfer from SnS; it also has sufficiently high potential for H2 evolution. The overall activity is determined by the competitive interfacial electron transfer between SnS/metal-oxide and metal-oxide/water. Therefore, constructing appropriate heterojunctions is necessary for further improving photoelectrochemical systems.

Magnetometry with Low-Resistance Proximity Josephson Junction

NASA Astrophysics Data System (ADS)

Jabdaraghi, R. N.; Peltonen, J. T.; Golubev, D. S.; Pekola, J. P.

2018-06-01

We characterize a niobium-based superconducting quantum interference proximity transistor (Nb-SQUIPT) and its key constituent formed by a Nb-Cu-Nb SNS weak link. The Nb-SQUIPT and SNS devices are fabricated simultaneously in two separate lithography and deposition steps, relying on Ar ion cleaning of the Nb contact surfaces. The quality of the Nb-Cu interface is characterized by measuring the temperature-dependent equilibrium critical supercurrent of the SNS junction. In the Nb-SQUIPT device, we observe a maximum flux-to-current transfer function value of about 55 nA/Φ_0 in the sub-gap regime of bias voltages. This results in suppression of power dissipation down to a few fW. Low-bias operation of the device with a relatively low probe junction resistance decreases the dissipation by up to two orders of magnitude compared to a conventional device based on an Al-Cu-Al SNS junction and an Al tunnel probe (Al-SQUIPT).

Fabrication of 2D SnS2/g-C3N4 heterojunction with enhanced H2 evolution during photocatalytic water splitting.

PubMed

Liu, Enzhou; Chen, Jibing; Ma, Yongning; Feng, Juan; Jia, Jia; Fan, Jun; Hu, Xiaoyun

2018-08-15

In this work, the 2D SnS 2 /g-C 3 N 4 heterojunctions were successfully prepared by heating the homogeneous dispersion of SnS 2 nanosheets and g-C 3 N 4 nanosheets using a microwave muffle. SEM, TEM and HRTEM images indicated that the SnS 2 nanosheets were loaded on the surface of the g-C 3 N 4 nanosheets. The UV-vis spectra show that the absorption intensity of the as-prepared samples was increased and the absorption range was also extended from 420 nm to approximately 600 nm. The H 2 production rate over 5 wt% SnS 2 /g-C 3 N 4 can reach 972.6 μmol·h -1 ·g -1 under visible light irradiation (λ > 420 nm) using TEOA as the sacrifice agent and Pt as the electron trap, which is 2.9 and 25.6 times higher than those of the pristine g-C 3 N 4 and SnS 2 , respectively. According to the obtained PL spectra, photocurrent and EIS spectra, the enhanced performance for H 2 generation over the heterojunctions is primarily ascribed to the rapid charge transfer arising from the suitable band gap positions leading to an improved photocatalytic performance. The recycling experiments indicated that the as-prepared composites exhibit good stability in H 2 production. Additionally, a possible enhanced mechanism for H 2 evolution was deduced based on the results obtained by various characterization techniques. Copyright © 2018 Elsevier Inc. All rights reserved.

Making Record-efficiency SnS Solar Cells by Thermal Evaporation and Atomic Layer Deposition

PubMed Central

Jaramillo, Rafael; Steinmann, Vera; Yang, Chuanxi; Hartman, Katy; Chakraborty, Rupak; Poindexter, Jeremy R.; Castillo, Mariela Lizet; Gordon, Roy; Buonassisi, Tonio

2015-01-01

Tin sulfide (SnS) is a candidate absorber material for Earth-abundant, non-toxic solar cells. SnS offers easy phase control and rapid growth by congruent thermal evaporation, and it absorbs visible light strongly. However, for a long time the record power conversion efficiency of SnS solar cells remained below 2%. Recently we demonstrated new certified record efficiencies of 4.36% using SnS deposited by atomic layer deposition, and 3.88% using thermal evaporation. Here the fabrication procedure for these record solar cells is described, and the statistical distribution of the fabrication process is reported. The standard deviation of efficiency measured on a single substrate is typically over 0.5%. All steps including substrate selection and cleaning, Mo sputtering for the rear contact (cathode), SnS deposition, annealing, surface passivation, Zn(O,S) buffer layer selection and deposition, transparent conductor (anode) deposition, and metallization are described. On each substrate we fabricate 11 individual devices, each with active area 0.25 cm2. Further, a system for high throughput measurements of current-voltage curves under simulated solar light, and external quantum efficiency measurement with variable light bias is described. With this system we are able to measure full data sets on all 11 devices in an automated manner and in minimal time. These results illustrate the value of studying large sample sets, rather than focusing narrowly on the highest performing devices. Large data sets help us to distinguish and remedy individual loss mechanisms affecting our devices. PMID:26067454

Under the influence of Facebook? Excess use of social networking sites and drinking motives, consequences, and attitudes in college students

PubMed Central

Hormes, Julia M.

2016-01-01

Background and aims Excessive use of social networking sites (SNS) has recently been conceptualized as a behavioral addiction (i.e., “disordered SNS use”) using key criteria for the diagnosis of substance dependence and shown to be associated with a variety of impairments in psychosocial functioning, including an increased risk of problem drinking. This study sought to characterize associations between “disordered SNS use” and attitudes towards alcohol, drinking motives, and adverse consequences resulting from alcohol use in young adults. Methods Undergraduate students (n = 537, 64.0% female, mean age = 19.63 years, SD = 4.24) reported on their use of SNSs and completed the Alcohol Use Disorders Identification Test, Temptation and Restraint Inventory, Approach and Avoidance of Alcohol and Drinking Motives Questionnaires, and Drinker Inventory of Consequences. Results Respondents meeting previously established criteria for “disordered SNS use” were significantly more likely to use alcohol to cope with negative affect and to conform to perceived social norms, reported significantly more conflicting (i.e., simultaneous positive and negative) attitudes towards alcohol, and had experienced significantly more, and more frequent adverse consequences from drinking in their inter- and intrapersonal, physical, and social functioning, compared to individuals without problems related to SNS use. Discussion and conclusions Findings add to an emerging body of literature suggesting a link between excess or maladaptive SNS use and problems related to alcohol in young adults and point to emotion dysregulation and coping motives as potential shared risk factors for substance and behavioral addictions in this demographic. PMID:28092186

Under the influence of Facebook? Excess use of social networking sites and drinking motives, consequences, and attitudes in college students.

PubMed

Hormes, Julia M

2016-03-01

Background and aims Excessive use of social networking sites (SNS) has recently been conceptualized as a behavioral addiction (i.e., "disordered SNS use") using key criteria for the diagnosis of substance dependence and shown to be associated with a variety of impairments in psychosocial functioning, including an increased risk of problem drinking. This study sought to characterize associations between "disordered SNS use" and attitudes towards alcohol, drinking motives, and adverse consequences resulting from alcohol use in young adults. Methods Undergraduate students (n = 537, 64.0% female, mean age = 19.63 years, SD = 4.24) reported on their use of SNSs and completed the Alcohol Use Disorders Identification Test, Temptation and Restraint Inventory, Approach and Avoidance of Alcohol and Drinking Motives Questionnaires, and Drinker Inventory of Consequences. Results Respondents meeting previously established criteria for "disordered SNS use" were significantly more likely to use alcohol to cope with negative affect and to conform to perceived social norms, reported significantly more conflicting (i.e., simultaneous positive and negative) attitudes towards alcohol, and had experienced significantly more, and more frequent adverse consequences from drinking in their inter- and intrapersonal, physical, and social functioning, compared to individuals without problems related to SNS use. Discussion and conclusions Findings add to an emerging body of literature suggesting a link between excess or maladaptive SNS use and problems related to alcohol in young adults and point to emotion dysregulation and coping motives as potential shared risk factors for substance and behavioral addictions in this demographic.

Feasibility of Real-Time Near-Infrared Fluorescence Tracer Imaging in Sentinel Node Biopsy for Oral Cavity Cancer Patients.

PubMed

Christensen, Anders; Juhl, Karina; Charabi, Birgitte; Mortensen, Jann; Kiss, Katalin; Kjær, Andreas; von Buchwald, Christian

2016-02-01

Sentinel node biopsy (SNB) is an established method in oral squamous cell carcinoma (OSCC) for staging the cN0 neck and to select patients who will benefit from a neck dissection. Near-infrared fluorescence (NIRF) imaging has the potential to improve the SNB procedure by facilitating intraoperative visual identification of the sentinel lymph node (SN). The purpose of this study was to evaluate the feasibility of fluorescence tracer imaging for SN detection in conjunction with conventional radio-guided technique. Prospective study of patients with primary OSCC planned for tumor resection and SNB. Thirty patients were injected peritumorally with a bimodal tracer (ICG-99mTc-Nanocoll) followed by lymphoscintigraphy and SPECT/CT to define the SNs and their anatomic allocation preoperatively. SNs were detected intraoperatively with a hand-held gamma-probe and a hand-held NIRF camera. In 29 of 30 subjects (97%), all preoperatively defined SNs could be identified intraoperatively using a combination of radioactive and fluorescence guidance. A total of 94 SNs (mean 3, range 1-5) that were both radioactive and fluorescent ex vivo were harvested. Eleven of 94 SNs (12%) could only be identified in vivo using NIRF imaging, and the majority of those were located in level 1 close to the primary tumor. A combined fluorescent and radioactive tracer for SNB is feasible, and the additional use of NIRF imaging may improve the accuracy of SN identification in oral cancer patients. Intraoperative fluorescence guidance seems of particular value when SNs are located in close proximity to the injection site.

Qzone use and depression among Chinese adolescents: A moderated mediation model.

PubMed

Niu, Geng-Feng; Luo, Yi-Jun; Sun, Xiao-Jun; Zhou, Zong-Kui; Yu, Feng; Yang, Shen-Long; Zhao, Liang

2018-04-15

Social networking sites (SNSs), which provide abundant social comparison opportunities, are ubiquitous around the world, especially among adolescents. In China, Qzone stands out as the most popular SNS. Due to the opportunity it provides for meticulous self-presentation, SNS may give the impression that others are doing better, which is detrimental to individuals' well-being. Based on social comparison theory, the current study aimed to investigate the association between Chinese adolescents' SNS (Qzone) use and depression, as well as the mediating role of negative social comparison and the moderating role of self-esteem. A total of 764 adolescents (aged 12-18 years, M = 14.23, SD = 1.75), who had an active Qzone account, were recruited voluntarily to complete questionnaires on Qzone use intensity, negative social comparison on Qzone, self-esteem, and depression. More intense Qzone use was associated with higher level of negative social comparison on Qzone, which fully mediated the association between Qzone use and depression. Moreover, the mediating effect of negative social comparison on Qzone was moderated by self-esteem. The specific link between Qzone use and negative social comparison was weaker among adolescents with high self-esteem than those with low self-esteem. As all the data in this study were self-reported and cross-sectional, causal associations cannot be identified. Additionally, the specific activities on SNS were not identified. Negative social comparison may be a key factor and mechanism accounting for the positive association between SNS use and depression, while self-esteem could protect adolescents from the adverse outcome of SNS use. Copyright © 2018 Elsevier B.V. All rights reserved.

Reach, engagement, and effectiveness: a systematic review of evaluation methodologies used in health promotion via social networking sites.

PubMed

Lim, Megan S C; Wright, Cassandra J C; Carrotte, Elise R; Pedrana, Alisa E

2016-02-01

Issue addressed Social networking sites (SNS) are increasingly popular platforms for health promotion. Advancements in SNS health promotion require quality evidence; however, interventions are often not formally evaluated. This study aims to describe evaluation practices used in SNS health promotion. Methods A systematic review was undertaken of Medline, PsycINFO, Scopus, EMBASE, CINAHL Plus, Communication and Mass Media Complete, and Cochrane Library databases. Articles published between 2006 and 2013 describing any health promotion intervention delivered using SNS were included. Results Forty-seven studies were included. There were two main evaluation approaches: closed designs (n=23), which used traditional research designs and formal recruitment procedures; and open designs (n=19), which evaluated the intervention in a real-world setting, allowing unknown SNS users to interact with the content without enrolling in research. Closed designs were unable to assess reach and engagement beyond their research sample. Open designs often relied on weaker study designs with no use of objective outcome measures and yielded low response rates. Conclusions Barriers to evaluation included low participation rates, high attrition, unknown representativeness and lack of comparison groups. Acceptability was typically assessed among those engaged with the intervention, with limited population data available to accurately assess intervention reach. Few studies were able to assess uptake of the intervention in a real-life setting while simultaneously assessing effectiveness of interventions with research rigour. So what? Through use of quasi-experimental or well designed before-after evaluations, in combination with detailed engagement metrics, it is possible to balance assessment of effectiveness and reach to evaluate SNS health promotion.

The next evolution in radioguided surgery: breast cancer related sentinel node localization using a freehandSPECT-mobile gamma camera combination

PubMed Central

Engelen, Thijs; Winkel, Beatrice MF; Rietbergen, Daphne DD; KleinJan, Gijs H; Vidal-Sicart, Sergi; Olmos, Renato A Valdés; van den Berg, Nynke S; van Leeuwen, Fijs WB

2015-01-01

Accurate pre- and intraoperative identification of the sentinel node (SN) forms the basis of the SN biopsy procedure. Gamma tracing technologies such as a gamma probe (GP), a 2D mobile gamma camera (MGC) or 3D freehandSPECT (FHS) can be used to provide the surgeon with radioguidance to the SN(s). We reasoned that integrated use of these technologies results in the generation of a “hybrid” modality that combines the best that the individual radioguidance technologies have to offer. The sensitivity and resolvability of both 2D-MGC and 3D-FHS-MGC were studied in a phantom setup (at various source-detector depths and using varying injection site-to-SN distances), and in ten breast cancer patients scheduled for SN biopsy. Acquired 3D-FHS-MGC images were overlaid with the position of the phantom/patient. This augmented-reality overview image was then used for navigation to the hotspot/SN in virtual-reality using the GP. Obtained results were compared to conventional gamma camera lymphoscintigrams. Resolution of 3D-FHS-MGC allowed identification of the SNs at a minimum injection site (100 MBq)-to-node (1 MBq; 1%) distance of 20 mm, up to a source-detector depth of 36 mm in 2D-MGC and up to 24 mm in 3D-FHS-MGC. A clinically relevant dose of approximately 1 MBq was clearly detectable up to a depth of 60 mm in 2D-MGC and 48 mm in 3D-FHS-MGC. In all ten patients at least one SN was visualized on the lymphoscintigrams with a total of 12 SNs visualized. 3D-FHS-MGC identified 11 of 12 SNs and allowed navigation to all these visualized SNs; in one patient with two axillary SNs located closely to each other (11 mm), 3D-FHS-MGC was not able to distinguish the two SNs. In conclusion, high sensitivity detection of SNs at an injection site-to-node distance of 20 mm-and-up was possible using 3D-FHS-MGC. In patients, 3D-FHS-MGC showed highly reproducible images as compared to the conventional lymphoscintigrams. PMID:26069857

Solution-processable glass LiI-Li 4SnS 4 superionic conductors for all-solid-state Li-ion batteries

DOE PAGES

Kern Ho Park; Oh, Dae Yang; Choi, Young Eun; ...

2015-12-22

The new, highly conductive (4.1 × 10 –4 S cm –1 at 30 °C), highly deformable, and dry-air-stable glass 0.4LiI-0.6Li 4SnS 4 is prepared using a homogeneous methanol solution. Furthermore, the solution process enables the wetting of any exposed surface of the active materials with highly conductive solidified electrolytes (0.4LiI-0.6Li 4SnS 4), resulting in considerable improvements in electrochemical performances of these electrodes over conventional mixture electrodes.

Mining Archived HYSPEC User Data to Analyze the Prompt Pulse at the SNS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, Michael B.; Iverson, Erik B.; Gallmeier, Franz X.

The Hybrid-Spectrometer (HYSPEC) is one of 17 instruments currently operated at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratories (ORNL). The secondary spectrometer of this instrument is located inside an out-building off the north side of the SNS instrument hall. HYSPEC has experienced a larger background feature than similar inelastic instruments since its commissioning in 2011. This background feature is caused by a phenomenon known as the “prompt pulse” which is an essential part of neutron production in a pulsed spallation source but comes with unfortunate side effects.

Sensing Properties of GO and Amine-Silica Nanoparticles Functionalized QCM Sensors for Detection of Formaldehyde

NASA Astrophysics Data System (ADS)

Wang, Zhenqiang; Yang, Mingqing; He, Junhui

2014-12-01

In the current work, graphene oxides (GO) and Amine-Functionalized Silica Nanoparticles (NH2-SNs) were used as sensing layer on quart crystal microbalance (QCM) for detection of HCHO gas. The GO and NH2-SNs functionalized QCM resonators all had a significant response to HCHO gas. The sensitivity of GO functionalized QCM resonator is 0.04 Hz/(μgṡppm), which is four times as high as that of NH2-SNs functionalized QCM resonator (0.01 Hz/(μgṡppm)). The GO functionalized QCM resonators would be of benefit in area of environmental applications.

Evaluation and utilization of beam simulation codes for the SNS ion source and low energy beam transport developmenta)

NASA Astrophysics Data System (ADS)

Han, B. X.; Welton, R. F.; Stockli, M. P.; Luciano, N. P.; Carmichael, J. R.

2008-02-01

Beam simulation codes PBGUNS, SIMION, and LORENTZ-3D were evaluated by modeling the well-diagnosed SNS base line ion source and low energy beam transport (LEBT) system. Then, an investigation was conducted using these codes to assist our ion source and LEBT development effort which is directed at meeting the SNS operational and also the power-upgrade project goals. A high-efficiency H- extraction system as well as magnetic and electrostatic LEBT configurations capable of transporting up to 100mA is studied using these simulation tools.

Partially Oxidized SnS2 Atomic Layers Achieving Efficient Visible-Light-Driven CO2 Reduction.

PubMed

Jiao, Xingchen; Li, Xiaodong; Jin, Xiuyu; Sun, Yongfu; Xu, Jiaqi; Liang, Liang; Ju, Huanxin; Zhu, Junfa; Pan, Yang; Yan, Wensheng; Lin, Yue; Xie, Yi

2017-12-13

Unraveling the role of surface oxide on affecting its native metal disulfide's CO 2 photoreduction remains a grand challenge. Herein, we initially construct metal disulfide atomic layers and hence deliberately create oxidized domains on their surfaces. As an example, SnS 2 atomic layers with different oxidation degrees are successfully synthesized. In situ Fourier transform infrared spectroscopy spectra disclose the COOH* radical is the main intermediate, whereas density-functional-theory calculations reveal the COOH* formation is the rate-limiting step. The locally oxidized domains could serve as the highly catalytically active sites, which not only benefit for charge-carrier separation kinetics, verified by surface photovoltage spectra, but also result in electron localization on Sn atoms near the O atoms, thus lowering the activation energy barrier through stabilizing the COOH* intermediates. As a result, the mildly oxidized SnS 2 atomic layers exhibit the carbon monoxide formation rate of 12.28 μmol g -1 h -1 , roughly 2.3 and 2.6 times higher than those of the poorly oxidized SnS 2 atomic layers and the SnS 2 atomic layers under visible-light illumination. This work uncovers atomic-level insights into the correlation between oxidized sulfides and CO 2 reduction property, paving a new way for obtaining high-efficiency CO 2 photoreduction performances.

Silver colloidal nanoparticle stability: influence on Candida biofilms formed on denture acrylic.

PubMed

Monteiro, Douglas Roberto; Takamiya, Aline Satie; Feresin, Leonardo Perina; Gorup, Luiz Fernando; de Camargo, Emerson Rodrigues; Delbem, Alberto Carlos Botazzo; Henriques, Mariana; Barbosa, Debora Barros

2014-08-01

Our aim in this study was to evaluate how the chemical stability of silver nanoparticles (SNs) influences their efficacy against Candida albicans and C. glabrata biofilms. Several parameters of SN stability were tested, namely, temperature (50ºC, 70ºC, and 100ºC), pH (5.0 and 9.0), and time of contact (5 h and 24 h) with biofilms. The control was defined as SNs without temperature treatment, pH 7, and 24 h of contact. These colloidal suspensions at 54 mg/L were used to treat mature Candida biofilms (48 h) formed on acrylic. Their efficacy was determined by total biomass and colony-forming unit quantification. Data were analyzed using analysis of variance and the Bonferroni post hoc test (α = 0.05). The temperature and pH variations of SNs did not affect their efficacy against the viable cells of Candida biofilms (P > 0.05). Moreover, the treatment periods were not decisive in terms of the susceptibility of Candida biofilms to SNs. These findings provide an important advantage of SNs that may be useful in the treatment of Candida-associated denture stomatitis. © The Author 2014. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Thermoelectric Properties of SnS with Na-Doping.

PubMed

Zhou, Binqiang; Li, Shuai; Li, Wen; Li, Juan; Zhang, Xinyue; Lin, Siqi; Chen, Zhiwei; Pei, Yanzhong

2017-10-04

Tin sulfide (SnS), a low-cost compound from the IV-VI semiconductors, has attracted particular attention due to its great potential for large-scale thermoelectric applications. However, pristine SnS shows a low carrier concentration, which leads to a low thermoelectric performance. In this work, sodium is utilized to substitute Sn to increase the hole concentration and consequently improve the thermoelectric power factor. The resultant Hall carrier concentration up to ∼10 19 cm -3 is the highest concentration reported so far for this compound. This further leads to the highest thermoelectric figure of merit, zT of 0.65, reported so far in polycrystalline SnS. The temperature-dependent Hall mobility shows a transition of carrier-scattering source from a grain boundary potential below 400 K to acoustic phonons at higher temperatures. The electronic transport properties can be well understood by a single parabolic band (SPB) model, enabling a quantitative guidance for maximizing the thermoelectric power factor. Using the experimental lattice thermal conductivity, a maximal zT of 0.8 at 850 K is expected when the carrier concentration is further increased to ∼1 × 10 20 cm -3 , according to the SPB model. This work not only demonstrates SnS as a promising low-cost thermoelectric material but also details the material parameters that fundamentally determine the thermoelectric properties.

Overview of Privacy in Social Networking Sites (SNS)

NASA Astrophysics Data System (ADS)

Powale, Pallavi I.; Bhutkar, Ganesh D.

2013-07-01

Social Networking Sites (SNS) have become an integral part of communication and life style of people in today's world. Because of the wide range of services offered by SNSs mostly for free of cost, these sites are attracting the attention of all possible Internet users. Most importantly, users from all age groups have become members of SNSs. Since many of the users are not aware of the data thefts associated with information sharing, they freely share their personal information with SNSs. Therefore, SNSs may be used for investigating users' character and social habits by familiar or even unknown persons and agencies. Such commercial and social scenario, has led to number of privacy and security threats. Though, all major issues in SNSs need to be addressed, by SNS providers, privacy of SNS users is the most crucial. And therefore, in this paper, we have focused our discussion on "privacy in SNSs". We have discussed different ways of Personally Identifiable Information (PII) leakages from SNSs, information revelation to third-party domains without user consent and privacy related threats associated with such information sharing. We expect that this comprehensive overview on privacy in SNSs will definitely help in raising user awareness about sharing data and managing their privacy with SNSs. It will also help SNS providers to rethink about their privacy policies.

Effect of intrinsic electronic defect states on the morphology and optoelectronic properties of Sn-rich SnS particles

NASA Astrophysics Data System (ADS)

Singh, Chetan C.; Panda, Emila

2018-05-01

A small variation in the elemental composition of a chemical compound can cause the formation of additional electronic defect states in the material, thereby altering the overall microstructure and thus induced properties. In this work, we observed chemical constitution-induced modification in the morphology and optoelectronic properties of SnS. To this end, SnS particles were prepared using the solution chemical route and were characterized using a wide range of experimental techniques, such as x-ray diffractometry, field emission scanning electron microscopy, high resolution transmission electron microscopy, energy dispersive spectroscopy (EDS), x-ray photoelectron spectroscopy (XPS), UV-Vis spectrophotometry, and scanning tunneling spectroscopy (STS). All these SnS particles are found to be Sn-rich and p-type. However, distinctly different morphologies (i.e., flower-like and aggregated ones) are observed. These are then correlated with the electronic defect states, which are induced because of the presence of Sn vacancies, Sn antisites, and/or Sn interstitials. A combination of EDS, XPS, and STS data confirmed the presence of a higher concentration of Sn vacancies along with lower quantities of Sn interstitials and/or antisites in the SnS particles with flower-like morphologies giving rise to higher hole concentration, which subsequently leads to reduced transport, optical band gaps, and barrier heights.

Physiological stress responses predict sexual functioning and satisfaction differently in women who have and have not been sexually abused in childhood

PubMed Central

Meston, Cindy M.; Lorenz, Tierney A.

2012-01-01

Physiological responses to sexual stimuli may contribute to the increased rate of sexual problems seen in women with childhood sexual abuse (CSA) histories. We compared two physiological stress responses as predictors of sexual function and satisfaction, sympathetic nervous system (SNS) activation and cortisol in women with (CSA, N = 136) and without CSA histories (NSA, N = 102). In CSA survivors, cortisol response to sexual stimuli did not significantly predict sexual functioning; however, in NSA women, cortisol increases were associated with poorer sexual functioning, and decreases with higher functioning. For women with CSA histories, lower SNS activity was associated with poorer sexual functioning. For CSA survivors with low lifetime trauma, lower SNS activity was associated with higher sexual satisfaction; for women with high lifetime trauma, the reverse was true. Decreased SNS activity during sexual stimuli predicted higher sexual functioning in NSA women with low lifetime exposure to traumatic events, but lower sexual functioning in those with high exposure. Differences between women with and without CSA histories in the association between cortisol and SNS response and sexual functioning and satisfaction suggests that CSA causes disruptions in both short and long-term stress responses to sexual stimuli that perpetuate into adulthood. PMID:24748915

Neutron Scattering and Diffraction Studies of Fluids and Fluid-Solid Interactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cole, David R; Herwig, Kenneth W; Mamontov, Eugene

2006-01-01

There can be no disputing the fact that neutron diffraction and scattering have made a clear contribution to our current understanding of the structural and dynamical characteristics of liquid water and water containing dissolved ions at ambient conditions and to a somewhat lesser degree other state conditions involving a change in temperature and pressure. Indeed, a molecular-level understanding of how fluids (e.g., water, CO{sub 2}, CH{sub 4}, higher hydrocarbons, etc.) interact with and participate in reactions with other solid earth materials are central to the development of predictive models that aim to quantify a wide array of geochemical processes. Inmore » the context of natural systems, interrogation of fluids and fluid-solid interactions at elevated temperatures and pressures is an area requiring much more work, particularly for complex solutions containing geochemically relevant cations, anions, and other important dissolved species such as CO{sub 2} or CH{sub 4}. We have tried to describe a series of prototypical interfacial and surface problems using neutron scattering to stimulate the thinking of earth scientists interested applying some of these approaches to confined systems of mineralogical importance. Our ability to predict the molecular-level properties of fluids and fluid-solid interactions relies heavily on the synergism between experiments such as neutron diffraction or inelastic neutron scattering and molecular-based simulations. Tremendous progress has been made in closing the gap between experimental observations and predicted behavior based on simulations due to improvements in the experimental methodologies and instrumentation on the one hand, and the development of new potential models of water and other simple and complex fluids on the other. For example there has been an emergence of studies taking advantage of advanced computing power that can accommodate the demands of ab initio molecular dynamics. On the neutron instrumentation side while much of the quasielastic work described has been performed using instrumentation located at reactor based sources, the advent of 2{sup nd} generation spallation neutron sources like ISIS, new generation sources like the SNS at the Oak Ridge National Laboratory and the low repetition rate 2{sup nd} target station at ISIS offer significant opportunities for the study of interfacial and entrained liquids. At the very least, an improvement of the counting statistics by one to two orders of magnitude on many instruments such as vibrational and time-of-flight spectrometers at SNS will allow parametric studies of many systems which otherwise would be prohibitively time consuming. The extended-Q SANS diffractometer at SNS will offer very high intensity and unparalleled Q-range to extend the accessible length scale in the real space, from 0. 05 nm to150 nm. The backscattering spectrometer will provide very high intensity and excellent energy resolution through unprecedented range of energy transfers, thereby allowing simultaneous studies of translational and rotational diffusion components in various systems. The vibrational spectrometer with two orders of magnitude improvement in performance and the capability to perform simultaneous structural measurements should present exciting opportunities to and engender an entire new population of users in the neutron community.« less

High-T(sub c) Edge-geometry SNS Weak Links on Silicon-on-sapphire Substrates

NASA Technical Reports Server (NTRS)

Hunt, B.; Foote, M.; Pike, W.; Barner, J.; Vasquez, R.

1994-01-01

High-quality superconductor/normal-metal/superconductor(SNS) edge-geometry weak links have been produced on silicon-on-sapphire (SOS) substrates using a new SrTiO(sub 3)/'seed layer'/cubic-zirconia (YS2) buffer system.

Manganese-impregnated mesoporous silica nanoparticles for signal enhancement in MRI cell labelling studies

NASA Astrophysics Data System (ADS)

Guillet-Nicolas, Rémy; Laprise-Pelletier, Myriam; Nair, Mahesh M.; Chevallier, Pascale; Lagueux, Jean; Gossuin, Yves; Laurent, Sophie; Kleitz, Freddy; Fortin, Marc-André

2013-11-01

Mesoporous silica nanoparticles (MSNs) are used in drug delivery and cell tracking applications. As Mn2+ is already implemented as a ``positive'' cell contrast agent in preclinical imaging procedures (in the form of MnCl2 for neurological studies), the introduction of Mn in the porous network of MSNs would allow labelling cells and tracking them using MRI. These particles are in general internalized in endosomes, an acidic environment with high saline concentration. In addition, the available MSN porosity could also serve as a carrier to deliver medical/therapeutic substances through the labelled cells. In the present study, manganese oxide was introduced in the porous network of MCM-48 silica nanoparticles (Mn-M48SNs). The particles exhibit a narrow size distribution (~140 nm diam.) and high porosity (~60% vol.), which was validated after insertion of Mn. The resulting Mn-M48SNs were characterized by TEM, N2 physisorption, and XRD. Evidence was found with H2-TPR, and XPS characterization, that Mn(ii) is the main oxidation state of the paramagnetic species after suspension in water, most probably in the form of Mn-OOH. The colloidal stability as a function of time was confirmed by DLS in water, acetate buffer and cell culture medium. In NMR data, no significant evidence of Mn2+ leaching was found in Mn-M48SNs in acidic water (pH 6), up to 96 hours after suspension. High longitudinal relaxivity values of r1 = 8.4 mM-1 s-1 were measured at 60 MHz and 37 °C, with the lowest relaxometric ratios (r2/r1 = 2) reported to date for a Mn-MSN system. Leukaemia cells (P388) were labelled with Mn-M48SNs and nanoparticle cell internalization was confirmed by TEM. Finally, MRI contrast enhancement provided by cell labelling with escalated incubation concentrations of Mn-M48SNs was quantified at 1 T. This study confirmed the possibility of efficiently confining Mn into M48SNs using incipient wetness, while maintaining an open porosity and relatively high pore volume. Because these Mn-labelled M48SNs express strong ``positive'' contrast media properties at low concentrations, they are potentially applicable for cell tracking and drug delivery methodologies.Mesoporous silica nanoparticles (MSNs) are used in drug delivery and cell tracking applications. As Mn2+ is already implemented as a ``positive'' cell contrast agent in preclinical imaging procedures (in the form of MnCl2 for neurological studies), the introduction of Mn in the porous network of MSNs would allow labelling cells and tracking them using MRI. These particles are in general internalized in endosomes, an acidic environment with high saline concentration. In addition, the available MSN porosity could also serve as a carrier to deliver medical/therapeutic substances through the labelled cells. In the present study, manganese oxide was introduced in the porous network of MCM-48 silica nanoparticles (Mn-M48SNs). The particles exhibit a narrow size distribution (~140 nm diam.) and high porosity (~60% vol.), which was validated after insertion of Mn. The resulting Mn-M48SNs were characterized by TEM, N2 physisorption, and XRD. Evidence was found with H2-TPR, and XPS characterization, that Mn(ii) is the main oxidation state of the paramagnetic species after suspension in water, most probably in the form of Mn-OOH. The colloidal stability as a function of time was confirmed by DLS in water, acetate buffer and cell culture medium. In NMR data, no significant evidence of Mn2+ leaching was found in Mn-M48SNs in acidic water (pH 6), up to 96 hours after suspension. High longitudinal relaxivity values of r1 = 8.4 mM-1 s-1 were measured at 60 MHz and 37 °C, with the lowest relaxometric ratios (r2/r1 = 2) reported to date for a Mn-MSN system. Leukaemia cells (P388) were labelled with Mn-M48SNs and nanoparticle cell internalization was confirmed by TEM. Finally, MRI contrast enhancement provided by cell labelling with escalated incubation concentrations of Mn-M48SNs was quantified at 1 T. This study confirmed the possibility of efficiently confining Mn into M48SNs using incipient wetness, while maintaining an open porosity and relatively high pore volume. Because these Mn-labelled M48SNs express strong ``positive'' contrast media properties at low concentrations, they are potentially applicable for cell tracking and drug delivery methodologies. Electronic supplementary information (ESI) available: TEM images, particle size distributions, XRD, TPR, magnetometric profiles, T1 and T2 measurements at 60 MHz over time, NMRD profiles of materials, P388 cell proliferation assay after 4 h and T1-w. MR images of P388 cells incubated with a solution of M48SNs. See DOI: 10.1039/c3nr02969g

Decreased sensory nerve excitation and bone pain associated with mouse Lewis lung cancer in TRPV1-deficient mice.

PubMed

Wakabayashi, Hiroki; Wakisaka, Satoshi; Hiraga, Toru; Hata, Kenji; Nishimura, Riko; Tominaga, Makoto; Yoneda, Toshiyuki

2018-05-01

Bone pain is one of the most common and life-limiting complications of cancer metastasis to bone. Although the mechanism of bone pain still remains poorly understood, bone pain is evoked as a consequence of sensitization and excitation of sensory nerves (SNs) innervating bone by noxious stimuli produced in the microenvironment of bone metastases. We showed that bone is innervated by calcitonin gene-related protein (CGRP) + SNs extending from dorsal root ganglia (DRG), the cell body of SNs, in mice. Mice intratibially injected with Lewis lung cancer (LLC) cells showed progressive bone pain evaluated by mechanical allodynia and flinching with increased CGRP + SNs in bone and augmented SN excitation in DRG as indicated by elevated numbers of pERK- and pCREB-immunoreactive neurons. Immunohistochemical examination of LLC-injected bone revealed that the tumor microenvironment is acidic. Bafilomycin A1, a selective inhibitor of H + secretion from vacuolar proton pump, significantly alleviated bone pain, indicating that the acidic microenvironment contributes to bone pain. We then determined whether the transient receptor potential vanilloid 1 (TRPV1), a major acid-sensing nociceptor predominantly expressed on SNs, plays a role in bone pain by intratibially injecting LLC cells in TRPV1-deficient mice. Bone pain and SN excitation in the DRG and spinal dorsal horn were significantly decreased in TRPV1 -/- mice compared with wild-type mice. Our results suggest that TRPV1 activation on SNs innervating bone by the acidic cancer microenvironment in bone contributes to SN activation and bone pain. Targeting acid-activated TRPV1 is a potential therapeutic approach to cancer-induced bone pain.

Percutaneous tibial nerve stimulation vs sacral nerve stimulation for faecal incontinence: a comparative case-matched study.

PubMed

Al Asari, S; Meurette, G; Mantoo, S; Kubis, C; Wyart, V; Lehur, P-A

2014-11-01

The study assessed the initial experience with posterior tibial nerve stimulation (PTNS) for faecal incontinence and compared it with sacral nerve stimulation (SNS) performed in a single centre during the same timespan. A retrospective review of a prospectively collected database was conducted at the colorectal unit, University Hospital, Nantes, France, from May 2009 to December 2010. Seventy-eight patients diagnosed with chronic severe faecal incontinence underwent neurostimulation including PTNS in 21 and SNS in 57. The main outcome measures were faecal incontinence (Wexner score) and quality of life (Fecal Incontinence Quality of Life, FIQL) scores in a short-term follow-up. No significant differences were observed in patients' characteristics. Of 57 patients having SNS, 18 (32%) failed peripheral nerve evaluation and 39 (68%) received a permanent implant. Two (5%) developed a wound infection. No adverse effects were recorded in the PTNS group. There was no significant difference in the mean Wexner and FIQL scores between patients having PTNS and SNS at 6 (P = 0.39 and 0.09) and 12 months (P = 0.79 and 0.37). A 50% or more improvement in Wexner score was seen at 6 and 12 months in 47% and 30% of PTNS patients and in 50% and 58% of SNS patients with no significant difference between the groups. Posterior tibial nerve stimulation is a valid method of treating faecal incontinence in the short term when conservative treatment has failed. It is easier, simpler, cheaper and less invasive than SNS with a similar short-term outcome. Colorectal Disease © 2014 The Association of Coloproctology of Great Britain and Ireland.

One-pot, facile fabrication of a Ag3PO4-based ternary Z-scheme photocatalyst with excellent visible-light photoactivity and anti-photocorrosion performance

NASA Astrophysics Data System (ADS)

Xie, Mingyuan; Zhang, Tailiang

2018-04-01

Ag3PO4 can-not be widely used as an efficient photocatalyst in practical applications because of its susceptibility to photocorrosion. In this study, a novel, ternary Z-scheme photocatalytic system containing graphene oxide (GO), Ag3PO4 and SnS2 was fabricated by a one-pot, mild, in-situ precipitation method successfully. Using Rhodamine B (RhB) as the target of elimination, GO/Ag3PO4/SnS2 exhibited outstanding photocatalytic and anti-photocorrosion properties compared with those of Ag3PO4, Ag3PO4/SnS2 and GO/Ag3PO4. RhB was thoroughly degraded over the optimized GO/Ag3PO4/SnS2 nanocomposite after only 15 min under visible-light irradiation; this result is approximately 2.14, 3.33 and 5.83 times faster than that of GO/Ag3PO4, Ag3PO4/SnS2 and Ag3PO4, respectively. After three reuses, the photocatalytic activity of the ternary composite slightly decreased but remained 2.36, 4.08 and 12.70 times higher than those of the reused GO/Ag3PO4, Ag3PO4/SnS2 and Ag3PO4, respectively. In this system, the efficient separation and migration of the photoinduced current carriers in Ag3PO4 was realized through a double Z-scheme electron-transfer mechanism in which the GO nanosheets acted as the photocatalyst and electron mediator, thereby enhancing the photoactivity and stability of Ag3PO4. The present study provides a new perspective for enhancing photocatalytic and anti-photocorrosion performances in perishable photocatalysts for organic sewage and other environmental contamination treatments.

Increased yield pressure in the anal canal during sacral nerve stimulation: a pilot study with the functional lumen imaging probe.

PubMed

Haas, S; Liao, D; Gregersen, H; Lundby, L; Laurberg, S; Krogh, K

2017-02-01

Sacral nerve stimulation (SNS) is a well-established treatment for fecal incontinence but its mode of action remains obscure. Anal sphincter function is usually evaluated with manometry but resistance to distension may be a more appropriate parameter than luminal pressure. The functional lumen imaging probe allows detailed description of distension properties of the anal canal. Our objective in this study was to characterize the impact of SNS on distension properties of the anal canal in patients with idiopathic fecal incontinence. We studied 10 women (median age 64 [44-79] years) with idiopathic fecal incontinence at baseline and during SNS. The luminal geometry of the anal canal was examined with the FLIP at rest and during squeeze and the distensibility of the anal canal was investigated during filling of the bag. All patients were successfully treated with SNS and the mean Wexner Incontinence Score was reduced from 14.9 ± 4 to 7.1 ± 4.8 (P<.001). The pressure required to open the narrowest point of the anal canal during distension (yield pressure) increased from 14.5 ± 12.2 mmHg at baseline to 20.5 ± 13.3 mmHg during SNS (P<.01). The pressure-strain elastic modulus increased non-significantly from 2.2 ± 0.5 to 2.9 ± 1.6 kPa, indicating increased stiffness of the anal canal. The yield pressure and the resistance to distension increased in response to SNS for idiopathic fecal incontinence. This will inevitably increase the resistance to flow through the anal canal, which may contribute to the benefits of sacral nerve stimulation. © 2016 John Wiley & Sons Ltd.

Thermoelectric materials by using two-dimensional materials with negative correlation between electrical and thermal conductivity

PubMed Central

Lee, Myoung-Jae; Ahn, Ji-Hoon; Sung, Ji Ho; Heo, Hoseok; Jeon, Seong Gi; Lee, Woo; Song, Jae Yong; Hong, Ki-Ha; Choi, Byeongdae; Lee, Sung-Hoon; Jo, Moon-Ho

2016-01-01

In general, in thermoelectric materials the electrical conductivity σ and thermal conductivity κ are related and thus cannot be controlled independently. Previously, to maximize the thermoelectric figure of merit in state-of-the-art materials, differences in relative scaling between σ and κ as dimensions are reduced to approach the nanoscale were utilized. Here we present an approach to thermoelectric materials using tin disulfide, SnS2, nanosheets that demonstrated a negative correlation between σ and κ. In other words, as the thickness of SnS2 decreased, σ increased whereas κ decreased. This approach leads to a thermoelectric figure of merit increase to 0.13 at 300 K, a factor ∼1,000 times greater than previously reported bulk single-crystal SnS2. The Seebeck coefficient obtained for our two-dimensional SnS2 nanosheets was 34.7 mV K−1 for 16-nm-thick samples at 300 K. PMID:27323662

A COMPACTRIO-BASED BEAM LOSS MONITOR FOR THE SNS RF TEST CAVE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blokland, Willem; Armstrong, Gary A

2009-01-01

An RF Test Cave has been built at the Spallation Neutron Source (SNS) to be able to test RF cavities without interfering the SNS accelerator operations. In addition to using thick concrete wall to minimize radiation exposure, a Beam Loss Monitor (BLM) must abort the operation within 100 usec when the integrated radiation within the cave exceeds a threshold. We choose the CompactRIO platform to implement the BLM based on its performance, cost-effectiveness, and rapid development. Each in/output module is connected through an FPGA to provide point-by-point processing. Every 10 usec the data is acquired analyzed and compared to themore » threshold. Data from the FPGA is transferred using DMA to the real-time controller, which communicates to a gateway PC to talk to the SNS control system. The system includes diagnostics to test the hardware and integrates the losses in real-time. In this paper we describe our design, implementation, and results« less

Commissioning and operation of the horizontal test apparatus at SNS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Sang-Ho; Neustadt, Thomas S.; Howell, Matthew P.

2015-07-01

The Spallation Neutron Source (SNS) at Oak Ridge National Lab (ORNL) has built, commissioned and operated a Horizontal Test Apparatus (HTA) vessel in the Radiofrequency Test Facility (RFTF) test cave. It can be operated at 4.5 K using the independent Cryogenic Test Facility (CTF). The HTA is designed to be a single cavity version of an SNS cryomodule with the ability to demount and replace the cavity. It provides the functionality for testing a single dressed SNS medium or high beta Superconducting Radiofrequency (SRF) cavity. The HTA is currently being used in support of R&D for in-situ plasma processing ofmore » the cavity's inner niobium surface. The design and commissioning of the HTA at 4.5 K will be presented as well as results from operating the HTA including cool-down, warm-up and steady state operations. Results from plasma processing a warm SCRF cavity in-between cold HTA tests will also be reported.« less

Interaction between prenatal risk and infant parasympathetic and sympathetic stress reactivity predicts early aggression.

PubMed

Suurland, J; van der Heijden, K B; Huijbregts, S C J; van Goozen, S H M; Swaab, H

2017-09-01

Nonreciprocal action of the parasympathetic (PNS) and sympathetic (SNS) nervous systems, increases susceptibility to emotional and behavioral problems in children exposed to adversity. Little is known about the PNS and SNS in interaction with early adversity during infancy. Yet this is when the physiological systems involved in emotion regulation are emerging and presumably most responsive to environmental influences. We examined whether parasympathetic respiratory sinus arrhythmia (RSA) and sympathetic pre-ejection period (PEP) response and recovery at six months, moderate the association between cumulative prenatal risk and physical aggression at 20 months (N=113). Prenatal risk predicted physical aggression, but only in infants exhibiting coactivation of PNS and SNS (i.e., increase in RSA and decrease in PEP) in response to stress. These findings indicate that coactivation of the PNS and SNS in combination with prenatal risk is a biological marker for the development of aggression. Copyright © 2017 Elsevier B.V. All rights reserved.

Photocurrent Enhancement by a Rapid Thermal Treatment of Nanodisk-Shaped SnS Photocathodes.

PubMed

Patel, Malkeshkumar; Kumar, Mohit; Kim, Joondong; Kim, Yu Kwon

2017-12-21

Photocathodes made from the earth-abundant, ecofriendly mineral tin monosulfide (SnS) can be promising candidates for p/n-type photoelectrochemical cells because they meet the strict requirements of energy band edges for each individual photoelectrode. Herein we fabricated SnS-based cell that exhibited a prolonged photocurrent for 3 h at -0.3 V vs the reversible hydrogen electrode (RHE) in a 0.1 M HCl electrolyte. An enhancement of the cathodic photocurrent from 2 to 6 mA cm -2 is observed through a rapid thermal treatment. Mott-Schottky analysis of SnS samples revealed an anodic shift of 0.7 V in the flat band potential under light illumination. Incident photon-to-current conversion efficiency (IPCE) analysis indicates that an efficient charge transfer appropriate for solar hydrogen generation occurs at the -0.3 V vs RHE potential. This work shows that SnS is a promising material for photocathode in PEC cells and its performance can be enhanced via simple postannealing.

Coatable Li4 SnS4 Solid Electrolytes Prepared from Aqueous Solutions for All-Solid-State Lithium-Ion Batteries.

PubMed

Choi, Young Eun; Park, Kern Ho; Kim, Dong Hyeon; Oh, Dae Yang; Kwak, Hi Ram; Lee, Young-Gi; Jung, Yoon Seok

2017-06-22

Bulk-type all-solid-state lithium-ion batteries (ASLBs) for large-scale energy-storage applications have emerged as a promising alternative to conventional lithium-ion batteries (LIBs) owing to their superior safety. However, the electrochemical performance of bulk-type ASLBs is critically limited by the low ionic conductivity of solid electrolytes (SEs) and poor ionic contact between the active materials and SEs. Herein, highly conductive (0.14 mS cm -1 ) and dry-air-stable SEs (Li 4 SnS 4 ) are reported, which are prepared using a scalable aqueous-solution process. An active material (LiCoO 2 ) coated by solidified Li 4 SnS 4 from aqueous solutions results in a significant improvement in the electrochemical performance of ASLBs. Side-effects of the exposure of LiCoO 2 to aqueous solutions are minimized by using predissolved Li 4 SnS 4 solution. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

RF Conditioning and Testing of Fundamental Power Couplers for SNS Superconducting Cavity Production

DOE Office of Scientific and Technical Information (OSTI.GOV)

M. Stirbet; G.K. Davis; M. A. Drury

The Spallation Neutron Source (SNS) makes use of 33 medium beta (0.61) and 48 high beta (0.81) superconducting cavities. Each cavity is equipped with a fundamental power coupler, which should withstand the full klystron power of 550 kW in full reflection for the duration of an RF pulse of 1.3 msec at 60 Hz repetition rate. Before assembly to a superconducting cavity, the vacuum components of the coupler are submitted to acceptance procedures consisting of preliminary quality assessments, cleaning and clean room assembly, vacuum leak checks and baking under vacuum, followed by conditioning and RF high power testing. Similar acceptancemore » procedures (except clean room assembly and baking) were applied for the airside components of the coupler. All 81 fundamental power couplers for SNS superconducting cavity production have been RF power tested at JLAB Newport News and, beginning in April 2004 at SNS Oak Ridge. This paper gives details of coupler processing and RF high power-assessed performances.« less

The concurrent and longitudinal relationships between adolescents' use of social network sites and their social self-esteem.

PubMed

Valkenburg, Patti M; Koutamanis, Maria; Vossen, Helen G M

2017-11-01

The first aim of this study was to investigate the concurrent and longitudinal relationships between adolescents' use of social network sites (SNSs) and their social self-esteem. The second aim was to investigate whether the valence of the feedback that adolescents receive on SNSs can explain these relationships. We conducted a three-wave panel study among 852 pre- and early adolescents (10-15 years old). In line with earlier research, we found significant concurrent correlations between adolescents' SNS use and their social self-esteem in all three data waves. The longitudinal results only partly confirmed these concurrent findings: Adolescents' initial SNS use did not significantly influence their social self-esteem in subsequent years. In contrast, their initial social self-esteem consistently influenced their SNS use in subsequent years. The valence of online feedback from close friends and acquaintances explained the concurrent relationship between SNS use and social self-esteem, but not the longitudinal relationship. Results are discussed in terms of their methodological and theoretical implications.

Immersive Visual Analytics for Transformative Neutron Scattering Science

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steed, Chad A; Daniel, Jamison R; Drouhard, Margaret

The ORNL Spallation Neutron Source (SNS) provides the most intense pulsed neutron beams in the world for scientific research and development across a broad range of disciplines. SNS experiments produce large volumes of complex data that are analyzed by scientists with varying degrees of experience using 3D visualization and analysis systems. However, it is notoriously difficult to achieve proficiency with 3D visualizations. Because 3D representations are key to understanding the neutron scattering data, scientists are unable to analyze their data in a timely fashion resulting in inefficient use of the limited and expensive SNS beam time. We believe a moremore » intuitive interface for exploring neutron scattering data can be created by combining immersive virtual reality technology with high performance data analytics and human interaction. In this paper, we present our initial investigations of immersive visualization concepts as well as our vision for an immersive visual analytics framework that could lower the barriers to 3D exploratory data analysis of neutron scattering data at the SNS.« less

Initial observations of cavitation-induced erosion of liquid metal spallation target vessels at the Spallation Neutron Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

McClintock, David A; Riemer, Bernie; Ferguson, Phillip D

2012-01-01

During operation of the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory the mechanical properties of the AISI 316L target module are altered by high-energy neutron and proton radiation. The interior surfaces of the target vessel are also damaged by cavitation-induced erosion, which results from repetitive rapid heating of the liquid mercury by high-energy proton beam pulses. Until recently no observations of cavitation-induced erosion were possible for conditions prototypical to the SNS. Post irradiation examination (PIE) of the first and second operational SNS targets was performed to gain insight into the radiation-induced changes in mechanical properties of the 316Lmore » target material and the extent of cavitation-induced erosion to the target vessel inner surfaces. Observations of cavitation-induced erosion of the first and second operational SNS target modules are presented here, including images of the target vessel interiors and specimens removed from the target beam-entrance regions.« less

Influence of surface plasmon resonance of Sn nanoparticles and nanosheets on the photoluminescence and Raman spectra of SnS quantum dots

NASA Astrophysics Data System (ADS)

Warrier, Anita R.; Gandhimathi, R.

2018-04-01

We report on enhancement of photoluminescence of SnS quantum dots by embedding them in a mesh of Sn nanostructures. SnS quantum dots with band gap ˜2.7 eV are embedded in a mesh of Sn nanostructures, that are synthesized from tin chloride solution using sodium borohydride as reducing agent. The synthesized Sn nanostructures have a morphology dependent, tunable surface plasmon resonance ranging from UV region (295 nm) to visible region (400 nm) of the electromagnetic spectrum. In the SnS-Sn nanohybrids, the excitons are strongly coupled with plasmons leading to a shift in the excitonic binding energy (˜ 400 meV). Due to the influence of Sn nanoparticles on the SnS quantum dots, the photoluminescence and Raman line intensity is enhanced by an order of ˜103 The enhancement is more pronounced for Sn nanosheets due to the large surface area and visible light surface plasmon resonance.

Risks, Risk Factors, and Outcomes Associated with Phone and Internet Sexting Among University Students in the United States.

PubMed

Dir, Allyson L; Cyders, Melissa A

2015-08-01

Sexting, defined as the exchange of sexually suggestive pictures or messages via mobile phone or social networking sites (SNS), has received media attention for its prevalence and associated negative outcomes; however, research has not yet fully established risk factors for and resulting outcomes from sexting behaviors. The current study was the first empirical test of a causal path model in males and females, in which impulsivity-related traits and expectancies influence sexual behaviors through phone and SNS sexting. We also examined prevalence and perceived likelihood of common negative outcomes associated with sexting. Multiple regression and structural equation modeling (SEM) statistics were conducted on two independent undergraduate samples (n = 611 and 255). The best fitting SEM model (RMSEA = 0.04, CFI = 0.96, TLI = 0.94, and χ(2) = 176.06, df = 75, p < .001) demonstrated a significant indirect effect of sensation seeking on phone sexting behaviors through sex-related sexting expectancies and a significant indirect effect of sensation seeking on sexual hookup behaviors through phone sexting behaviors (b = 0.06, p = .03), but only for females. Reverse mediations and mediation with SNS were not significant. Negative outcomes were rare: sexts being spread to others was the most common negative sexting experience (n = 21, 12 %). This study suggests the viability of personality and expectancies affecting sexual hookup behaviors through engagement in sexting behaviors. It also suggests that although direct negative outcomes associated with sexting are thought to be common, they were rare in the current sample.

Assessing information needs and use of online resources for disease self-management in patients with rheumatoid arthritis: a qualitative study.

PubMed

des Bordes, Jude K A; Gonzalez, Elsa; Lopez-Olivo, Maria A; Shethia, Maithili; Nayak, Pratibha; Suarez-Almazor, Maria E

2018-07-01

To explore the information needs of patients with rheumatoid arthritis (RA) and their acceptance of online resources and Facebook in particular, as a source of information, interaction, and support among peers. Participants were adults with RA of ≤ 10 years duration, had ongoing or prior treatment with disease-modifying anti-rheumatic drugs or biologic agents, and internet access. We conducted 20 in-depth interviews using semi-structured interview guide to explore: (1) RA information needs, (2) use of self-management health behaviors, (3) use of internet resources for disease management, (4) role of peer support in health self-management, and (5) use of social networking sites (SNS) such as Facebook in disease management. Data were analyzed using content analysis and constant comparative methods. Participants were mainly female (85%), White (70%), and over 50 years old (70%). Specific information needs included knowledge regarding medications, disease course, pain control, diet, and exercise. Most participants had a narrow perception of SNS as a tool for disease management. However, they found SNS acceptable and were open to participating in a support group on Facebook with reasonable assurance of privacy. Although the overarching theme was RA information needs, the other themes contribute in supporting the robust emergence of Internet media in informing patients about their health and support systems. Our findings can inform the choice and format of materials to be considered for online education on self-management and social networking for RA patients.

Spin noise spectroscopy of rubidium atomic gas under resonant and non-resonant conditions

NASA Astrophysics Data System (ADS)

Ma, Jian; Shi, Ping; Qian, Xuan; Li, Wei; Ji, Yang

2016-11-01

The spin fluctuation in rubidium atom gas is studied via all-optical spin noise spectroscopy (SNS). Experimental results show that the integrated SNS signal and its full width at half maximum (FWHM) strongly depend on the frequency detuning of the probe light under resonant and non-resonant conditions. The total integrated SNS signal can be well fitted with a single squared Faraday rotation spectrum and the FWHM dependence may be related to the absorption profile of the sample. Project supported by the National Natural Science Foundation of China (Grant Nos. 91321310 and 11404325) and the National Basic Research Program of China (Grant No. 2013CB922304).

The Spallation Neutron Source (SNS) project accelerator systems

NASA Astrophysics Data System (ADS)

Holmes, Jeffrey A.; Alonso, Jose R.

1999-06-01

The SNS will be the world's leading accelerator-based neutron-scattering research facility when it begins operation in 2005. By delivering 1-MW of beam power to a heavy-metal target in short (<1 μs) bursts of 1-GeV protons, the SNS will provide intense neutron beams with flux levels at least a factor of five over present spallation sources. A multi-laboratory (LBNL, LANL, BNL, ANL and ORNL) collaboration, led by Oak Ridge National Laboratory, has developed a reference design that addresses the challenging technology issues associated with this project. This paper discusses the requirements, issues, and constraints that led to the present design choices.

The lateral line receptor array of cyprinids from different habitats.

PubMed

Schmitz, Anke; Bleckmann, Horst; Mogdans, Joachim

2014-04-01

The lateral line system of teleost fishes consists of an array of superficial and canal neuromasts (CN). Number and distribution of neuromasts and the morphology of the lateral line canals vary across species. We investigated the morphology of the lateral line system in four diurnal European cyprinids, the limnophilic bitterling (Rhodeus sericeus), the indifferent gudgeon (Gobio gobio), and ide (Leuciscus idus), and the rheophilic minnow (Phoxinus phoxinus). All fish had lateral line canals on head and trunk. The total number of both, CN and superficial neuromasts (SN), was comparable in minnow and ide but was greater than in gudgeon and bitterling. The ratio of SNs to CNs for the head was comparable in minnow and bitterling but was greater in gudgeon and ide. The SN-to-CN ratio for the trunk was greatest in bitterling. Polarization of hair cells in CNs was in the direction of the canal. Polarization of hair cells in SNs depended on body area. In cephalic SNs, hair cell polarization was dorso-ventral or rostro-caudal. In trunk SNs, it was rostro-caudal on lateral line scales and dorso-ventral on other trunk scales. On the caudal fin, hair cell polarization was rostro-caudal. The data show that, in the four species studied here, number, distribution, and orientation of CNs and SNs cannot be unequivocally related to habitat. Copyright © 2013 Wiley Periodicals, Inc.

Keep logging in! Experimental evidence showing the relation of affiliation needs to the idea of online social networking.

PubMed

Lee, Chun-Chia; Chiou, Wen-Bin

2013-06-01

As social networking sites (SNS) increasingly provide social connections that meet the need for affiliation, people are developing symbiotic relationships with these sites. Drawing on the notion that people motivated by affiliation may increase their attention to sources that provide social connections, we conducted a lab experiment to explore whether priming affiliation needs would prompt the idea of online social networking. Participants were randomly assigned to one of three between-subjects conditions (affiliation arousal, social exclusion, control) in which we employed the scrambled-sentence paradigm to manipulate affiliation motivations. Each experimental condition was followed by a modified Stroop task (a color naming task) to test reaction times to SNS and non-SNS terms (including general terms and brand names). People who were primed to think about a topic typically showed slowed reaction times for naming the color of related words (i.e., Stroop interference), as those words become more interesting and accessible. Confirming our hypothesis, participants took longer to name the font color of SNS-related words than that of matched general words when affiliation motivation was evoked. Moreover, priming with affiliation motivation created more Stroop interference for SNS brand names rather than for other global brand names. These results suggest that the idea of online social networking seems to have become deeply rooted in human social practices.

A Novel Loss Recovery and Tracking Scheme for Maneuvering Target in Hybrid WSNs.

PubMed

Qian, Hanwang; Fu, Pengcheng; Li, Baoqing; Liu, Jianpo; Yuan, Xiaobing

2018-01-25

Tracking a mobile target, which aims to timely monitor the invasion of specific target, is one of the most prominent applications in wireless sensor networks (WSNs). Traditional tracking methods in WSNs only based on static sensor nodes (SNs) have several critical problems. For example, to void the loss of mobile target, many SNs must be active to track the target in all possible directions, resulting in excessive energy consumption. Additionally, when entering coverage holes in the monitoring area, the mobile target may be missing and then its state is unknown during this period. To tackle these problems, in this paper, a few mobile sensor nodes (MNs) are introduced to cooperate with SNs to form a hybrid WSN due to their stronger abilities and less constrained energy. Then, we propose a valid target tracking scheme for hybrid WSNs to dynamically schedule the MNs and SNs. Moreover, a novel loss recovery mechanism is proposed to find the lost target and recover the tracking with fewer SNs awakened. Furthermore, to improve the robustness and accuracy of the recovery mechanism, an adaptive unscented Kalman filter (AUKF) algorithm is raised to dynamically adjust the process noise covariance. Simulation results demonstrate that our tracking scheme for maneuvering target in hybrid WSNs can not only track the target effectively even if the target is lost but also maintain an excellent accuracy and robustness with fewer activated nodes.

A Novel Loss Recovery and Tracking Scheme for Maneuvering Target in Hybrid WSNs

PubMed Central

Liu, Jianpo; Yuan, Xiaobing

2018-01-01

Tracking a mobile target, which aims to timely monitor the invasion of specific target, is one of the most prominent applications in wireless sensor networks (WSNs). Traditional tracking methods in WSNs only based on static sensor nodes (SNs) have several critical problems. For example, to void the loss of mobile target, many SNs must be active to track the target in all possible directions, resulting in excessive energy consumption. Additionally, when entering coverage holes in the monitoring area, the mobile target may be missing and then its state is unknown during this period. To tackle these problems, in this paper, a few mobile sensor nodes (MNs) are introduced to cooperate with SNs to form a hybrid WSN due to their stronger abilities and less constrained energy. Then, we propose a valid target tracking scheme for hybrid WSNs to dynamically schedule the MNs and SNs. Moreover, a novel loss recovery mechanism is proposed to find the lost target and recover the tracking with fewer SNs awakened. Furthermore, to improve the robustness and accuracy of the recovery mechanism, an adaptive unscented Kalman filter (AUKF) algorithm is raised to dynamically adjust the process noise covariance. Simulation results demonstrate that our tracking scheme for maneuvering target in hybrid WSNs can not only track the target effectively even if the target is lost but also maintain an excellent accuracy and robustness with fewer activated nodes. PMID:29370103

Online social networking services in the management of patients with diabetes mellitus: systematic review and meta-analysis of randomised controlled trials.

PubMed

Toma, Tania; Athanasiou, Thanos; Harling, Leanne; Darzi, Ara; Ashrafian, Hutan

2014-11-01

Social networking services (SNS) can facilitate real-time communication and feedback of blood glucose and other physiological data between patients and healthcare professionals. This systematic review and meta-analysis aims to summarise the current evidence surrounding the role of online social networking services in diabetes care. We performed a systematic literature review of the Medline, EMBASE and PsychINFO databases of all studies reporting HbA1c (glycated haemoglobin) as a measure of glycaemic control for social networking services in diabetes care. HbA1c, clinical outcomes and the type of technology used were extracted. Study quality and publication bias were assessed. SNS interventions beneficially reduced HbA1c when compared to controls, which was confirmed by sensitivity analysis. SNS interventions also significantly improved systolic and diastolic blood pressure, triglycerides and total cholesterol. Subgroup analysis according to diabetes type demonstrated that Type 2 diabetes patients had a significantly greater reduction in HbA1c than those with Type 1 diabetes. Online SNS provide a novel, feasible approach to improving glycaemic control, particularly in patients with Type 2 diabetes. Further mechanistic and cost-effectiveness studies are required to improve our understanding of SNS and its efficacy in diabetes care. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Social instability and immunity in rhesus monkeys: the role of the sympathetic nervous system.

PubMed

Capitanio, John P; Cole, Steven W

2015-05-26

Social instability can adversely affect endocrine, immune and health outcomes, and recent evidence suggests that the sympathetic nervous system (SNS) might mediate these effects. We conducted two studies with adult male rhesus monkeys (Macaca mulatta) to understand how social conditions affect measures of SNS activity and immune function. In Experiment 1, animals were socialized in stable social conditions, then were switched to unstable (stressful) social conditions, then were returned to stable conditions. Analysis revealed quadratic effects for measures of behaviour, urinary metabolites of epinephrine and norepinephrine, and expression of immune response genes: as expected, social instability adversely impacted most measures, and the effects remediated upon re-imposition of stable conditions. Cortisol levels were unaffected. In Experiment 2, we used the sympathomimetic drug methamphetamine to challenge the SNS; animals also underwent socialization in stable or unstable groups. Surprisingly, while methamphetamine elevated plasma catecholamines, responses in lymph nodes tracked the social, and not the drug, condition: social instability upregulated the density of SNS fibres in lymph nodes and downregulated Type I interferon gene expression. Together, these results indicate that the SNS is extremely sensitive to social conditions; full understanding of the adverse effects of social instability on health should therefore incorporate measures of this health-relevant system. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Neuroticism Magnifies the Detrimental Association between Social Media Addiction Symptoms and Wellbeing in Women, but Not in Men: a three-Way Moderation Model.

PubMed

Turel, Ofir; Poppa, Natalie Tasha; Gil-Or, Oren

2018-02-03

Addiction symptoms in relation to the use of social networking sites (SNS) can be associated with reduced wellbeing. However, the mechanisms that can control this association have not been fully characterized, despite their relevance to effective treatment of individuals presenting SNS addiction symptoms. In this study we hypothesize that sex and neuroticism, which are important determinants of how people evaluate and respond to addiction symptoms, moderate this association. To examine these assertions, we employed hierarchical linear and logistic regression techniques to analyze data collected with a cross-sectional survey of 215 Israeli college students who use SNS. Results lend support to the hypothesized negative association between SNS addiction symptoms and wellbeing (as well as potentially being at-risk for low mood/ mild depression), and the ideas that (1) this association is augmented by neuroticism, and (2) that the augmentation is stronger for women than for men. They demonstrated that the sexes may differ in their SNS addiction-wellbeing associations: while men had similar addiction symptoms -wellbeing associations across neuroticism levels, women with high levels of neuroticism presented much steeper associations compared to women with low neuroticism. This provides an interesting account of possible "telescoping effect", the idea that addicted women present a more severe clinical profile compared to men, in the case of technology-"addictions".

Investigating the differential effects of social networking site addiction and Internet gaming disorder on psychological health.

PubMed

Pontes, Halley M

2017-12-01

Background and aims Previous studies focused on examining the interrelationships between social networking site (SNS) addiction and Internet gaming disorder (IGD) in isolation. Moreover, little is known about the potential simultaneous differential effects of SNS addiction and IGD on psychological health. This study investigated the interplay between these two technological addictions and ascertained how they can uniquely and distinctively contribute to increasing psychiatric distress when accounting for potential effects stemming from sociodemographic and technology-related variables. Methods A sample of 509 adolescents (53.5% males) aged 10-18 years (mean = 13.02, SD = 1.64) were recruited. Results It was found that key demographic variables can play a distinct role in explaining SNS addiction and IGD. Furthermore, it was found that SNS addiction and IGD can augment the symptoms of each other, and simultaneously contribute to deterioration of overall psychological health in a similar fashion, further highlighting potentially common etiological and clinical course between these two phenomena. Finally, the detrimental effects of IGD on psychological health were found to be slightly more pronounced than those produced by SNS addiction, a finding that warrants additional scientific scrutiny. Discussion and conclusion The implications of these results are further discussed in light of the existing evidence and debates regarding the status of technological addictions as primary and secondary disorders.

Multi-phase structures of boron-doped copper tin sulfide nanoparticles synthesized by chemical bath deposition for optoelectronic devices

NASA Astrophysics Data System (ADS)

Rakspun, Jariya; Kantip, Nathakan; Vailikhit, Veeramol; Choopun, Supab; Tubtimtae, Auttasit

2018-04-01

We investigated the influence of boron doping on the structural, optical, and electrical properties of copper tin sulfide (CTS) nanoparticles coated on a WO3 surface and synthesized using chemical bath deposition. Boron doping at concentrations of 0.5, 1.0, 1.5, and 2.0 wt% was investigated. The X-ray diffraction pattern of CTS showed the presence of monoclinic Cu2Sn3S7, cubic Cu2SnS3, and orthorhombic Cu4SnS4. Boron doping influenced the preferred orientation of the nanoparticles for all phase structures and produced a lattice strain effect and changes in the dislocation density. Increasing the concentration of boron in CTS from 0.5 wt% to 2.0 wt% reduced the band gap for all phases of CTS from 1.46 to 1.29 eV and reduced the optical transmittance. Optical constants, such as the refractive index, extinction coefficient, and dissipation factor, were also obtained for B-doped CTS. The dispersion behavior of the refractive index was investigated in terms of a single oscillator model and the physical parameters were determined. Fourier transform infrared spectroscopy confirmed the successful synthesis of CTS nanoparticles. Cyclic voltammetry indicated that optimum boron doping (<1.5 wt% for all phases) resulted in desirable p-n junction behavior for optoelectronic applications.

Role of "Aplysia" Cell Adhesion Molecules during 5-HT-Induced Long-Term Functional and Structural Changes

ERIC Educational Resources Information Center

Han, Jin-Hee; Lim, Chae-Seok; Lee, Yong-Seok; Kandel, Eric R.; Kaang, Bong-Kiun

2004-01-01

We previously reported that five repeated pulses of 5-HT lead to down-regulation of the TM-apCAM isoform at the surface of "Aplysia" sensory neurons (SNs). We here examined whether apCAM down-regulation is required for 5-HT-induced long-term facilitation. We also analyzed the role of the cytoplasmic and extracellular domains by overexpressing…

Thermoelectric and phonon transport properties of two-dimensional IV-VI compounds.

PubMed

Shafique, Aamir; Shin, Young-Han

2017-03-30

We explore the thermoelectric and phonon transport properties of two-dimensional monochalcogenides (SnSe, SnS, GeSe, and GeS) using density functional theory combined with Boltzmann transport theory. We studied the electronic structures, Seebeck coefficients, electrical conductivities, lattice thermal conductivities, and figures of merit of these two-dimensional materials, which showed that the thermoelectric performance of monolayer of these compounds is improved in comparison compared to their bulk phases. High figures of merit (ZT) are predicted for SnSe (ZT = 2.63, 2.46), SnS (ZT = 1.75, 1.88), GeSe (ZT = 1.99, 1.73), and GeS (ZT = 1.85, 1.29) at 700 K along armchair and zigzag directions, respectively. Phonon dispersion calculations confirm the dynamical stability of these compounds. The calculated lattice thermal conductivities are low while the electrical conductivities and Seebeck coefficients are high. Thus, the properties of the monolayers show high potential toward thermoelectric applications.

Social Networking Postings: Views from School Principals

ERIC Educational Resources Information Center

Griffin, Marlynn M.; Lake, Robert L.

2012-01-01

Numerous recent media accounts indicate that teachers are being fired, put on probation, or otherwise censured because of information found on their social networking sites (SNS). While the literature in business, psychology, and pharmacy shows initial investigations of the impact of SNS information on hiring decisions, this area has not been…

Migraine-related healthcare resource use and costs for subjects prescribed fixed-dose combination sumatriptan/naproxen sodium vs. single-entity oral triptans in a managed care population in the USA.

PubMed

Runken, M Chris; Goodwin, Bridgett; Shah, Manan; Eaddy, Michael; D'Souza, Anna; Bowers, Brian; Bell, Christopher F

2015-02-01

Randomized clinical trials have demonstrated that the efficacy of a fixed-dose single-tablet combination containing sumatriptan and naproxen sodium (S/NS) was greater than either of its individual components. Simplifying drug regimens (e.g., via a fixed-dose combination) has been shown to improve "real-world" outcomes by reducing pill burden and treatment regimen complexity, improving adherence, and reducing healthcare resource use and associated costs; however, no studies assessing such outcomes have been conducted to date for the acute treatment of migraine. To assess migraine-related healthcare resource use and associated costs for subjects prescribed S/NS vs. subjects prescribed single-entity oral triptans (SOTs) within a managed care population in the USA. In this retrospective analysis of administrative claims data from July 1, 2008 to December 31, 2009 (IMS LifeLink), subjects meeting the following criteria were selected: one or more pharmacy claim(s) for either S/NS or SOT (index date), aged 18-64 years; at least one migraine diagnosis, and continuous enrollment in the 6 months prior to and post the index date. The study population was subsequently stratified for two analyses: triptan-naïve (triptan naïve in the 6-month period prior to the index date) and triptan-switch (triptan user in the 6-month period prior to the index date and switching to another triptan). Subjects prescribed S/NS were propensity-score matched with subjects prescribed SOT (triptan-naïve analysis: 1:3; triptan-switch analysis: 1:1) to assess differences in healthcare resource use and associated costs (2009 US$) between the S/NS and SOT groups. Results from the triptan-naïve and triptan-switch analyses suggest that subjects prescribed S/NS are likely to have similar healthcare resource use patterns as those either newly initiated on an SOT or switching SOTs, as measured by migraine medication use, migraine-related healthcare resource use, and all-cause healthcare resource use. One exception was the observed increased use of opioids in the SOT group compared with the S/NS group (change in mean number of tablets pre-index vs. post-index, S/NS vs. SOT; triptan-naïve analysis: 8.6 vs.18.3, p = 0.045; triptan-switch analysis: -8.2 vs. 17.7; p = 0.120). Total costs from the triptan-naïve analysis indicated that the S/NS group had lower migraine-related (US$744 vs. US$820; p = 0.067) and all-cause healthcare costs (US$4,391 vs. US$4,870; p = 0.040) when compared with the SOT group, driven by savings in medical costs (migraine-related: US$252 vs. US$380; p = 0.001; all-cause: US$3,023 vs. US$3,599; p = 0.014). However, no significant differences were observed for total costs from the triptan-switch analysis (migraine-related healthcare costs, S/NS vs. SOT: US$1,159 vs. US$1,117; p = 0.929; all-cause healthcare costs: US$5,128 vs. US$4,788; p = 0.381). Study results suggest similar healthcare resource use patterns and associated costs when comparing S/NS and SOT across a triptan-naïve and triptan-experienced population. While the current study focuses on direct medical costs, future studies should extend beyond such a perspective to explore functional status, productivity, and health-related quality of life and satisfaction, attributes not captured in administrative claims data, but nonetheless important treatment goals.

Life history and status of Shortnose Sturgeon (Acipenser brevirostrum LeSueur, 1818)

USGS Publications Warehouse

Kynard, Boyd; Bolden, Stephania; Kieffer, Micah; Collins, Mark; Brundage, Hal; Hilton, Eric; Litvak, Mark; Kinnison, Michael T.; King, Timothy L.; Peterson, Douglas C.

2016-01-01

Shortnose Sturgeon = SNS (Acipenser brevirostrum) is a small diadromous species with most populations living in large Atlantic coast rivers and estuaries of North America from New Brunswick, Canada, to GA, USA. There are no naturally landlocked populations, so all populations require access to fresh water and salt water to complete a natural life cycle. The species is amphidromous with use of fresh water and salt water (the estuary) varied across the species range, a pattern that may reflect whether freshwater or saltwater habitats provide optimal foraging and growth conditions. Migration is a dominant behavior during life history, beginning when fish are hatchling free embryos (southern SNS) or larvae (northeastern and far northern SNS). Migration continues by juveniles and nonspawning adult life stages on an individual time schedule with fish moving between natal river and estuary to forage or seek refuge, and by spawning adults migrating to and from riverine spawning grounds. Coastal movements by adults throughout the range (but particularly in the Gulf of Maine = GOM and among southern rivers) suggest widespread foraging, refuge use, and widespread colonization of new rivers. Colonization may also be occurring in the Potomac River, MD–VA–DC (midAtlantic region). Genetic studies (mtDNA and nDNA) identified distinct individual river populations of SNS, and recent rangewide nDNA studies identified five distinct evolutionary lineages of SNS in the USA: a northern metapopulation in GOM rivers; the Connecticut River; the Hudson River; a Delaware River–Chesapeake Bay metapopulation; and a large southern metapopulation (SC rivers to Altamaha River, GA). The Saint John River, NB, Canada, in the Bay of Fundy (north of the GOM), is the sixth distinct genetic lineage within SNS. Life history information from telemetry tracking supports the genetic information documenting extensive movement of adults among rivers within the three metapopulations. However, individual river populations with spawning adults are still the best basal unit for management and recovery planning. The focus on individual river populations should be complemented with attention to migratory processes and corridors that foster metapopulation level risks and benefits. The species may be extirpated at the center of the range, i.e., the midAtlantic region (Chesapeake Bay, MD–VA, and probably, NC), but large rivers in VA, including the James and Potomac rivers, need study. The largest SNS populations in GOM and northeastern rivers, like the Kennebec, Hudson, and Delaware rivers, typically have tens of thousands of adults. This contrasts with southern rivers, where rivers typically have much fewer (6000 adults). River damming in the 19th and 20th Centuries extirpated some populations, and also, created two dysfunctional segmented populations: the Connecticut River SNS in CT–MA and the SanteeCooper rivers–Lake Marion SNS in SC. The major anthropogenic impact on SNS in marine waters is fisheries bycatch. The major impacts that determine annual recruitment success occur in freshwater firstly, where adult spawning migrations and spawning are blocked or spawning success is affected by river regulation and secondly, where poor survival of early life stages is caused by river dredging, pollution, and unregulated impingement/entrainment in water withdrawal facilities. Climate warming has the potential to reduce abundance or eliminate SNS in many rivers, particularly in the South. In 1998, the National Marine Fisheries Service (NMFS) recommended management of 19 rivers as distinct population segments (DPSs) based on strong fidelity to natal rivers. A Biological Assessment completed in 2010 reaffirmed this approach. NMFS has not formally listed DPSs under the ESA and the species remains listed as endangered rangewide in the USA.

3D-QSAR and Molecular Docking Studies on Derivatives of MK-0457, GSK1070916 and SNS-314 as Inhibitors against Aurora B Kinase

PubMed Central

Zhang, Baidong; Li, Yan; Zhang, Huixiao; Ai, Chunzhi

2010-01-01

Development of anticancer drugs targeting Aurora B, an important member of the serine/threonine kinases family, has been extensively focused on in recent years. In this work, by applying an integrated computational method, including comparative molecular field analysis (CoMFA), comparative molecular similarity indices analysis (CoMSIA), homology modeling and molecular docking, we investigated the structural determinants of Aurora B inhibitors based on three different series of derivatives of 108 molecules. The resultant optimum 3D-QSAR models exhibited (q2 = 0.605, r2pred = 0.826), (q2 = 0.52, r2pred = 0.798) and (q2 = 0.582, r2pred = 0.971) for MK-0457, GSK1070916 and SNS-314 classes, respectively, and the 3D contour maps generated from these models were analyzed individually. The contour map analysis for the MK-0457 model revealed the relative importance of steric and electrostatic effects for Aurora B inhibition, whereas, the electronegative groups with hydrogen bond donating capacity showed a great impact on the inhibitory activity for the derivatives of GSK1070916. Additionally, the predictive model of the SNS-314 class revealed the great importance of hydrophobic favorable contour, since hydrophobic favorable substituents added to this region bind to a deep and narrow hydrophobic pocket composed of residues that are hydrophobic in nature and thus enhanced the inhibitory activity. Moreover, based on the docking study, a further comparison of the binding modes was accomplished to identify a set of critical residues that play a key role in stabilizing the drug-target interactions. Overall, the high level of consistency between the 3D contour maps and the topographical features of binding sites led to our identification of several key structural requirements for more potency inhibitors. Taken together, the results will serve as a basis for future drug development of inhibitors against Aurora B kinase for various tumors. PMID:21151441

3D-QSAR and molecular docking studies on derivatives of MK-0457, GSK1070916 and SNS-314 as inhibitors against Aurora B kinase.

PubMed

Zhang, Baidong; Li, Yan; Zhang, Huixiao; Ai, Chunzhi

2010-11-02

Development of anticancer drugs targeting Aurora B, an important member of the serine/threonine kinases family, has been extensively focused on in recent years. In this work, by applying an integrated computational method, including comparative molecular field analysis (CoMFA), comparative molecular similarity indices analysis (CoMSIA), homology modeling and molecular docking, we investigated the structural determinants of Aurora B inhibitors based on three different series of derivatives of 108 molecules. The resultant optimum 3D-QSAR models exhibited (q(2) = 0.605, r(2) (pred) = 0.826), (q(2) = 0.52, r(2) (pred) = 0.798) and (q(2) = 0.582, r(2) (pred) = 0.971) for MK-0457, GSK1070916 and SNS-314 classes, respectively, and the 3D contour maps generated from these models were analyzed individually. The contour map analysis for the MK-0457 model revealed the relative importance of steric and electrostatic effects for Aurora B inhibition, whereas, the electronegative groups with hydrogen bond donating capacity showed a great impact on the inhibitory activity for the derivatives of GSK1070916. Additionally, the predictive model of the SNS-314 class revealed the great importance of hydrophobic favorable contour, since hydrophobic favorable substituents added to this region bind to a deep and narrow hydrophobic pocket composed of residues that are hydrophobic in nature and thus enhanced the inhibitory activity. Moreover, based on the docking study, a further comparison of the binding modes was accomplished to identify a set of critical residues that play a key role in stabilizing the drug-target interactions. Overall, the high level of consistency between the 3D contour maps and the topographical features of binding sites led to our identification of several key structural requirements for more potency inhibitors. Taken together, the results will serve as a basis for future drug development of inhibitors against Aurora B kinase for various tumors.

Magnetic Correlations in the Triangular Antiferromagnet TbInO3

NASA Astrophysics Data System (ADS)

Sala, Gabriele; Clark, Lucy; Maharaj, Dalini; Stone, Matthew B.; Knight, Kevin S.; Cheong, Sang-Wook; Gaulin, Bruce D.

TbInO3 crystallizes with a hexagonal P63 cm structure in which layers of edge-sharing triangles of magnetic Tb3+ ions are separated by non-magnetic [InO5]7- units. TbInO3, therefore, realizes an excellent opportunity to explore the behavior of a two-dimensional magnetic triangular lattice, a canonical model of geometric frustration. Here we present our study of a polycrystalline sample of TbInO3. Our high resolution powder neutron diffraction data (HRPD, ISIS) of TbInO3 confirm that the triangular layers of Tb3+ remain undistorted to at least 0 . 46 K. Magnetic susceptibility data follow Curie-Weiss behavior over a wide range of T with θ = - 17 . 19 (3) K indicating the dominance of antiferromagnetic correlations. The susceptibility data also show an absence of conventional long-range spin order down to at least 0 . 55 K, reflecting the frustrated nature of TbInO3. Elastic magnetic diffuse neutron scattering (SEQUOIA, SNS) is observed below ~ 15 K, due to the presence of static two-dimensional spin correlations. The spectrum of crystal field excitations in TbInO3 appears to have an exotic form due to the existence of two crystallographically distinct Tb3+ sites and leads to a strong Ising anisotropy of the spin symmetry.

SNS Central Helium Liquefier spare Carbon Bed installation and commissioning

NASA Astrophysics Data System (ADS)

DeGraff, B.; Howell, M.; Kim, S.; Neustadt, T.

2017-12-01

The Spallation Neutron Source (SNS) Central Helium Liquefier (CHL) at Oak Ridge National Laboratory (ORNL) has been without major operations downtime since operations were started back in 2006. This system utilizes a vessel filled with activated carbon as the final major component to remove oil vapor from the compressed helium circuit prior to insertion into the system’s cryogenic cold box. The need for a spare carbon bed at SNS due to the variability of carbon media lifetime calculation to adsorption efficiency will be discussed. The fabrication, installation and commissioning of this spare carbon vessel will be presented. The novel plan for connecting the spare carbon vessel piping to the existing infrastructure will be presented.

75 FR 70938 - Information Collection Request to Office of Management and Budget; OMB Control numbers: 1625-0108.

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-19

... minimize the burden of the collections on respondents, including the use of automated collection techniques... Undocumented Vessels. OMB Control Number: 1625-0108. Summary: The Standard Numbering System (SNS) collects.... 12302(a) authorized the Secretary to prescribe, by regulation, a SNS that may be implemented by the...

Discovery of New Mineral Butianite, Ni6SnS2, an Alteration Phase from Allende

NASA Astrophysics Data System (ADS)

Ma, C.

2017-07-01

Butianite (Ni6SnS2) is a new chalcogenide mineral from an Allende CAI, along with nuwaite (Ni6GeS2), formed from a late-stage sulfidation process, where Ni-Fe metals reacted with a low-temperature fluid enriched in S, Ge, Sn and Te.

Cortisol and Children's Adjustment: The Moderating Role of Sympathetic Nervous System Activity

ERIC Educational Resources Information Center

El-Sheikh, Mona; Erath, Stephen A.; Buckhalt, Joseph A.; Granger, Douglas A.; Mize, Jacquelyn

2008-01-01

We examined relations among cortisol, markers of sympathetic nervous system (SNS) activity (including salivary alpha-amylase and skin conductance level), and children's adjustment. We also tested the Bauer et al. ("Journal of Developmental and Behavioral Pediatrics," 23(2), 102-113, 2002) hypothesis that interactions between the SNS and cortisol…

From CMS to SNS: Educational Networking for Urban Teachers

ERIC Educational Resources Information Center

Chen, Pearl

2011-01-01

A complex view of the socioeconomic digital divide in urban schools requires us to address not only the gaps in access to technology, but also inequities in access to human support, digital content, and "effective pedagogical" approaches to technology integration. This study explored the use of social networking site (SNS) as a platform…

A Phenomenological Investigation of Social Networking Privacy Awareness through a Media Literacy Lens

ERIC Educational Resources Information Center

Magolis, David; Briggs, Audra

2016-01-01

This research study focused on the social networking site (SNS) awareness of undergraduate students, examining their experiences through the type and extent of the information shared on their SNSs in order to discover the students' experiences with SNS privacy. A phenomenological research approach was used to interview eight undergraduates to…

77 FR 31172 - Airworthiness Directives; Bell Helicopter Textron Canada Limited Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-25

... control of the helicopter. Transport Canada (TC), which is the aviation authority for Canada, issued... BHTC Model 427 helicopters, serial numbers (S/Ns) 56001 through 56084, and S/Ns 58001 and 58002. TC..., TC, its technical representative, has notified us of the unsafe condition described in the TC AD. We...

Factors Affecting Social Network Use by Students in Indonesia

ERIC Educational Resources Information Center

Kristianto, Budhi

2017-01-01

Background: Although Indonesia is one of the world's most populated countries with a high penetration of internet usage there has been little research on SNS usage in Indonesia, especially involving children. Instead, SNS research in Indonesia has focused on university students and political, marketing, and disaster mitigation issues. Aim/Purpose:…

Public Health Interventions for School Nursing Practice

ERIC Educational Resources Information Center

Schaffer, Marjorie A.; Anderson, Linda J. W.; Rising, Shannon

2016-01-01

School nurses (SNs) use public health nursing knowledge and skills to provide nursing services to school populations. The Public Health Intervention Wheel is a practice framework that can be used to explain and guide public health nursing interventions. SNs who were also members of the National Association of School Nurses completed an electronic…

Social Networking Practices in School Psychology: Have Moral Panic Concerns Been Overstated?

ERIC Educational Resources Information Center

Segool, Natasha K.; Goforth, Anisa N.; Bowman, Nicholas; Pham, Andy

2016-01-01

The almost ubiquitous use of Facebook and other social networking sites (SNSs) by adults in the United States raises important practice considerations for school psychologists. This study examined the SNS practices of school psychologists, graduate trainers, and graduate students to explore (a) SNS use training experiences for school…

Benefits of early specialized nutritional support in malnourished patients.

PubMed

Morán López, Jesús Manuel; Beneítez Moralejo, Belén; Piedra León, María; Enciso Izquierdo, Fidel Jesús; Luengo Pérez, Luis Miguel; Amado Señaris, José Antonio

2017-04-07

Disease related malnutrition (DRM) is highly prevalent in Spain, affecting 23% of in-hospital patients, and is associated with clinical complications. Specialized nutritional support (SNS) can reduce these complications. Prospective study carried out in standard clinical practice conditions to test if SNS during the first 5 days of hospitalization, or subsequently, was associated to a lower length of stay or reduced complications in patients with a NRS-2002 score≥3 points. In the group of patients who initiated early SNS, the length of stay was 8.83 days shorter than in the group with a later introduction (95% CI 3.55-14.10); nevertheless, the higher prevalence of male and oncological patients in this group could have impacted the results. A tendency towards a statistically significant lower mortality rate and a reduced amount of total complications was described. The early introduction of SNS (within the first 5 days of hospitalization) in patients with DRM was associated with a 32.4% reduction in the length of stay. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

One-step growth of thin film SnS with large grains using MOCVD.

PubMed

Clayton, Andrew J; Charbonneau, Cecile M E; Tsoi, Wing C; Siderfin, Peter J; Irvine, Stuart J C

2018-01-01

Thin film tin sulphide (SnS) films were produced with grain sizes greater than 1 μm using a one-step metal organic chemical vapour deposition process. Tin-doped indium oxide (ITO) was used as the substrate, having a similar work function to molybdenum typically used as the back contact, but with potential use of its transparency for bifacial illumination. Tetraethyltin and ditertiarybutylsulphide were used as precursors with process temperatures 430-470 °C to promote film growth with large grains. The film stoichiometry was controlled by varying the precursor partial pressure ratios and characterised with energy dispersive X-ray spectroscopy to optimise the SnS composition. X-ray diffraction and Raman spectroscopy were used to determine the phases that were present in the film and revealed that small amounts of ottemannite Sn 2 S 3 was present when SnS was deposited on to the ITO using optimised growth parameters. Interaction at the SnS/ITO interface to form Sn 2 S 3 was deduced to have resulted for all growth conditions.

Influence of a multidimensional measure of attitudes on motives to use social networking sites.

PubMed

Krishnan, Archana; Hunt, Daniel Scot

2015-03-01

Positive attitudes toward a new communication technology tend to be a significant motivator in subsequent adoption and use. The recent spurt in the adoption of social media tools such as social networking sites (SNSs) demands the examination of attitudinal variables on motives to use these Web sites. This study explicated a multidimensional measure of attitudes toward SNSs and tested a theoretical model to examine the effect of attitudes on motives to use SNSs and SNS activity. Participants (N=674) completed a cross-sectional survey consisting of measures of attitudes toward SNSs, motives of SNS use, and level of activity. Results showed support for a revised model in which attitudinal variables-ease of use, self-disclosure, and social connection-strongly predicted motives of SNS use such as passing time, information/entertainment, social conformity, and, most importantly, socialization. The motive of using SNSs as a social tool superseded the direct effect of other motives on SNS activity, suggesting that users' primary activity on SNSs was for socialization and for relational development and maintenance.

The Relationship Between Online Social Network Use, Sexual Risk Behaviors, and HIV Sero-Status Among a Sample of Predominately African American and Latino Men Who have Sex with Men (MSM) Social Media Users.

PubMed

Chiu, ChingChe J; Young, Sean D

2015-06-01

Social networking technologies have emerged as potential platforms to reach HIV(+) MSM in HIV interventions. This study sought to compare use of online social networking sites (SNSs) and sexual risk behaviors between HIV(+) and HIV(-) individuals among a sample of predominately African American and Latino SNS-using MSM. A total of 112 MSM Facebook users were recruited online and offline and completed an online survey. We performed regression models to assess the association between HIV status, SNS use, and sexual risk behaviors. After adjusting for age, race, and employment status, being HIV positive was significantly associated with a greater number of sexual partners (ARR = 2.84, p = 0.0017) and lower comfort levels of discussing HIV/STI status on SNSs (AOR: 0.23, p = 0.011). Findings suggest that HIV status is associated with sexual risk behaviors and SNS use among SNS-using MSM. We discuss the implications for online HIV prevention.

Data Mining and Privacy of Social Network Sites' Users: Implications of the Data Mining Problem.

PubMed

Al-Saggaf, Yeslam; Islam, Md Zahidul

2015-08-01

This paper explores the potential of data mining as a technique that could be used by malicious data miners to threaten the privacy of social network sites (SNS) users. It applies a data mining algorithm to a real dataset to provide empirically-based evidence of the ease with which characteristics about the SNS users can be discovered and used in a way that could invade their privacy. One major contribution of this article is the use of the decision forest data mining algorithm (SysFor) to the context of SNS, which does not only build a decision tree but rather a forest allowing the exploration of more logic rules from a dataset. One logic rule that SysFor built in this study, for example, revealed that anyone having a profile picture showing just the face or a picture showing a family is less likely to be lonely. Another contribution of this article is the discussion of the implications of the data mining problem for governments, businesses, developers and the SNS users themselves.

Improving cycle stability of SnS anode for sodium-ion batteries by limiting Sn agglomeration

NASA Astrophysics Data System (ADS)

Wang, Wenhui; Shi, Liang; Lan, Danni; Li, Quan

2018-02-01

Flower-like SnS nanostructures are obtained by a simple solvothermal method for anode applications in Na-ion batteries. We show experimental evidence of progressive Sn agglomeration and crystalline Na2S enrichment at the end of de-sodiation process of the SnS electrode, both of which contribute to the capacity decay of the electrode upon repeated cycles. By replacing the commonly adopted acetylene black conductive additive with multi-wall carbon nanotubes (MWCNT), the cycle stability of the SnS electrode is largely improved, which correlates well with the observed suppression of both Sn agglomeration and Na2S enrichment at the end of de-sodiation cycle. A full cell is assembled with the SnS/MWCNT anode and the P2-Na2/3Ni1/3Mn1/2Ti1/6O2 cathode. An initial energy density of 262 Wh/kg (normalized to the total mass of cathode and anode) is demonstrated for the full cell, which retains 71% of the first discharge capacity after 40 cycles.

The First ASME Code Stamped Cryomodule at SNS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Howell, M P; Crofford, M T; Douglas, D L

The first spare cryomodule for the Spallation Neutron Source (SNS) has been designed, fabricated, and tested by SNS personnel. The approach to design for this cryomodule was to hold critical design features identical to the original design such as bayonet positions, coupler positions, cold mass assembly, and overall footprint. However, this is the first SNS cryomodule that meets the pressure requirements put forth in the 10 CFR 851: Worker Safety and Health Program. The most significant difference is that Section VIII of the ASME Boiler and Pressure Vessel Code was applied to the vacuum vessel of this cryomodule. Applying themore » pressure code to the helium vessels within the cryomodule was considered. However, it was determined to be schedule prohibitive because it required a code case for materials that are not currently covered by the code. Good engineering practice was applied to the internal components to verify the quality and integrity of the entire cryomodule. The design of the cryomodule, fabrication effort, and cryogenic test results will be reported in this paper.« less

The continued development of the Spallation Neutron Source external antenna H- ion sourcea)

NASA Astrophysics Data System (ADS)

Welton, R. F.; Carmichael, J.; Desai, N. J.; Fuga, R.; Goulding, R. H.; Han, B.; Kang, Y.; Lee, S. W.; Murray, S. N.; Pennisi, T.; Potter, K. G.; Santana, M.; Stockli, M. P.

2010-02-01

The U.S. Spallation Neutron Source (SNS) is an accelerator-based, pulsed neutron-scattering facility, currently in the process of ramping up neutron production. In order to ensure that the SNS will meet its operational commitments as well as provide for future facility upgrades with high reliability, we are developing a rf-driven, H- ion source based on a water-cooled, ceramic aluminum nitride (AlN) plasma chamber. To date, early versions of this source have delivered up to 42 mA to the SNS front end and unanalyzed beam currents up to ˜100 mA (60 Hz, 1 ms) to the ion source test stand. This source was operated on the SNS accelerator from February to April 2009 and produced ˜35 mA (beam current required by the ramp up plan) with availability of ˜97%. During this run several ion source failures identified reliability issues, which must be addressed before the source re-enters production: plasma ignition, antenna lifetime, magnet cooling, and cooling jacket integrity. This report discusses these issues, details proposed engineering solutions, and notes progress to date.

Single-Crystal Growth of Cl-Doped n-Type SnS Using SnCl2 Self-Flux.

PubMed

Iguchi, Yuki; Inoue, Kazutoshi; Sugiyama, Taiki; Yanagi, Hiroshi

2018-06-05

SnS is a promising photovoltaic semiconductor owing to its suitable band gap energy and high optical absorption coefficient for highly efficient thin film solar cells. The most significant carnage is demonstration of n-type SnS. In this study, Cl-doped n-type single crystals were grown using SnCl 2 self-flux method. The obtained crystal was lamellar, with length and width of a few millimeters and thickness ranging between 28 and 39 μm. X-ray diffraction measurements revealed the single crystals had an orthorhombic unit cell. Since the ionic radii of S 2- and Cl - are similar, Cl doping did not result in substantial change in lattice parameter. All the elements were homogeneously distributed on a cleaved surface; the Sn/(S + Cl) ratio was 1.00. The crystal was an n-type degenerate semiconductor with a carrier concentration of ∼3 × 10 17 cm -3 . Hall mobility at 300 K was 252 cm 2 V -1 s -1 and reached 363 cm 2 V -1 s -1 at 142 K.

Examining the scope and patterns of deliberate self-injurious cutting content in popular social media.

PubMed

Miguel, Elizabeth M; Chou, Tommy; Golik, Alejandra; Cornacchio, Danielle; Sanchez, Amanda L; DeSerisy, Mariah; Comer, Jonathan S

2017-09-01

Social networking services (SNS) have rapidly become a central platform for adolescents' social interactions and media consumption patterns. The present study examined a representative sample of publicly accessible content related to deliberate self-injurious cutting across three SNS platforms: Twitter, Tumblr, and Instagram. Data collection simulated searches for publicly available deliberate self-injury content on Twitter, Tumblr, and Instagram. Over a six-month period at randomly generated time points, data were obtained by searching "#cutting" on each SNS platform and collecting the first 10 posts generated. Independent evaluators coded posts for presence of the following: (a) graphic content, (b) negative self-evaluations, (c) references to mental health terms, (d) discouragement of deliberate self-injury, and (e) recovery-oriented resources. Differences across platforms were examined. Data collection yielded a sample of 1,155 public posts (770 of which were related to mental health). Roughly 60% of sampled posts depicted graphic content, almost half included negative self-evaluations, only 9.5% discouraged self-injury, and <1% included formal recovery resources. Instagram posts displayed the greatest proportion of graphic content and negative self-evaluations, whereas Twitter exhibited the smallest proportion of each. Findings characterize the graphic nature of online SNS deliberate self-injury content and the relative absence of SNS-posted resources for populations seeking out deliberate self-injurious cutting content. Mental health professionals must recognize the rapidly changing landscape of adolescent media consumption, influences, and social interaction as they may pertain to self-harm patterns. © 2017 Wiley Periodicals, Inc.

High-Performance Near-Infrared Photodetectors Based on p-type SnX (X=S, Se) Nanowires Grown via Chemical Vapor Deposition.

PubMed

Zheng, Dingshan; Fang, Hehai; Long, Mingsheng; Wu, Feng; Wang, Peng; Gong, Fan; Wu, Xing; Ho, Johnny C; Liao, Lei; Hu, Weida

2018-06-21

Because of the distinct electronic properties and strong interaction with light, quasi-one-dimensional nanowires (NWs) with semiconducting property have been demonstrated with tremendous potential for various technological applications, especially electronics and optoelectronics. However, until now, most of the state-of-the-art NW photodetectors are predominantly based on the N-type NW channel. Here, we successfully synthesized P-type SnSe and SnS NWs via chemical vapor deposition method and fabricated high-performance single SnSe and SnS NW photodetectors. Importantly, these two NW devices exhibit the impressive photodetection performance with the high photoconductive gain of 1.5 × 10 4 (2.8 × 10 4 ), good responsivity of 1.0× 10 4 A W -1 (1.6× 10 4 A W -1 ) as well as excellent detectivity of 3.3 × 10 12 Jones (2.4 × 10 12 Jones) under near-infrared illumination at a bias of 3 V for the SnSe NW (SnS NW) channel. The rise and fall times can be as efficient as 460 and 520 μs (1.2 and 15.1 ms), respectively, for the SnSe NW (SnS NW) device. Moreover, the spatially resolved photocurrent mapping of the devices further reveals the bias-dependent photocurrent generation. All these results evidently demonstrate that the P-type SnSe and SnS NWs have great potential to be applied in next-generation high-performance optoelectronic devices.

Electronic Structure of Helium Atom in a Quantum Dot

NASA Astrophysics Data System (ADS)

Saha, Jayanta K.; Bhattacharyya, S.; Mukherjee, T. K.

2016-03-01

Bound and resonance states of helium atom have been investigated inside a quantum dot by using explicitly correlated Hylleraas type basis set within the framework of stabilization method. To be specific, precise energy eigenvalues of bound 1sns (1Se) (n = 1-6) states and the resonance parameters i.e. positions and widths of 1Se states due to 2sns (n = 2-5) and 2pnp (n = 2-5) configurations of confined helium below N = 2 ionization threshold of He+ have been estimated. The two-parameter (Depth and Width) finite oscillator potential is used to represent the confining potential due to the quantum dot. It has been explicitly demonstrated that the electronic structural properties become sensitive functions of the dot size. It is observed from the calculations of ionization potential that the stability of an impurity ion within a quantum dot may be manipulated by varying the confinement parameters. A possibility of controlling the autoionization lifetime of doubly excited states of two-electron ions by tuning the width of the quantum cavity is also discussed here. TKM Gratefully Acknowledges Financial Support under Grant No. 37(3)/14/27/2014-BRNS from the Department of Atomic Energy, BRNS, Government of India. SB Acknowledges Financial Support under Grant No. PSW-160/14-15(ERO) from University Grants Commission, Government of India

Control of Bone Remodeling by the Peripheral Sympathetic Nervous System

PubMed Central

Campbell, Preston; Ma, Yun

2013-01-01

The skeleton is no longer seen as a static, isolated, and mostly structural organ. Over the last two decades, a more complete picture of the multiple functions of the skeleton has emerged, and its interactions with a growing number of apparently unrelated organs have become evident. The skeleton not only reacts to mechanical loading and inflammatory, hormonal, and mineral challenges, but also acts of its own accord by secreting factors controlling the function of other tissues, including the kidney and possibly the pancreas and gonads. It is thus becoming widely recognized that it is by nature an endocrine organ, in addition to a structural organ and site of mineral storage and hematopoiesis. Consequently and by definition, bone homeostasis must be tightly regulated and integrated with the biology of other organs to maintain whole body homeostasis, and data uncovering the involvement of the central nervous system (CNS) in the control of bone remodeling support this concept. The sympathetic nervous system (SNS) represents one of the main links between the CNS and the skeleton, based on a number of anatomic, pharmacologic, and genetic studies focused on β-adrenergic receptor (βAR) signaling in bone cells. The goal of this report was to review the data supporting the role of the SNS and βAR signaling in the regulation of skeletal homeostasis. PMID:23765388

Integrated modeling/analyses of thermal-shock effects in SNS targets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taleyarkhan, R.P.; Haines, J.

1996-06-01

In a spallation neutron source (SNS), extremely rapid energy pulses are introduced in target materials such as mercury, lead, tungsten, uranium, etc. Shock phenomena in such systems may possibly lead to structural material damage beyond the design basis. As expected, the progression of shock waves and interaction with surrounding materials for liquid targets can be quite different from that in solid targets. The purpose of this paper is to describe ORNL`s modeling framework for `integrated` assessment of thermal-shock issues in liquid and solid target designs. This modeling framework is being developed based upon expertise developed from past reactor safety studies,more » especially those related to the Advanced Neutron Source (ANS) Project. Unlike previous separate-effects modeling approaches employed (for evaluating target behavior when subjected to thermal shocks), the present approach treats the overall problem in a coupled manner using state-of-the-art equations of state for materials of interest (viz., mercury, tungsten and uranium). That is, the modeling framework simultaneously accounts for localized (and distributed) compression pressure pulse generation due to transient heat deposition, the transport of this shock wave outwards, interaction with surrounding boundaries, feedback to mercury from structures, multi-dimensional reflection patterns & stress induced (possible) breakup or fracture.« less

Optimization of Neuromodulation for Bladder Control in a Rat Cystitis Model.

PubMed

Su, Xin; Nickles, Angela; Nelson, Dwight E

2016-01-01

In a bladder overactivity model of cystitis induced by intravesical infusion of acetic acid (a.a.), several parameters of spinal nerve stimulation (SNS) were optimized using continuous infusion cystometry. The optimal stimulation was further characterized through measurements of urodynamic function using single-fill cystometry. In anesthetized male rats, a cannula was placed into the bladder dome for saline or 0.3% a.a. infusion and intravesical pressure monitoring. For SNS, two teflon-coated stainless steel electrodes were placed bilaterally under each of the L6 spinal nerves, and current stimulation was controlled independently using two Grass stimulators. Stimulation of 1 Hz or 50 Hz at motor threshold (Tmot ) was ineffective for altering bladder activities, but 10-Hz SNS increased the infused volume (IV) in a stimulation intensity-dependent fashion (P < 0.01, mixed model repeated analysis). Pairwise comparisons of IV differences to each stimulation intensity show that IV during 1 × Tmot stimulation was significantly larger than 0 × Tmot (no stim, P = 0.001), while the IV during 2 × Tmot stimulation was significantly larger than other intensities tested (P < 0.01). The mean IV (±SEM) during 0 × Tmot (no stim), 0.5 × Tmot , 1 × Tmot , and 2 × Tmot were 0.23 ± 0.04 mL, 0.25 ± 0.03 mL, 0.26 ± 0.03 mL, and 0.40 ± 0.04 mL, respectively. In single-fill cystometry, 10-Hz SNS at 1 × Tmot and 2 × Tmot stimulation increased the IV, or voiding duration and threshold pressure. SNS did not produce significant effects on basal pressure and micturition pressure. SNS significantly attenuates hypersensitive micturition reflex; 10 Hz and high-intensity stimulation are mostly effective. Acute peripheral nerve activation increases the functional bladder capacity, which may be via mechanisms on the afferent arm of the bladder micturition reflex. © 2015 International Neuromodulation Society.

Sacral neurostimulation for urinary retention: 10-year experience from one UK centre.

PubMed

Datta, Soumendra N; Chaliha, Charlotte; Singh, Anubha; Gonzales, Gwen; Mishra, Vibhash C; Kavia, Rajesh B C; Kitchen, Neil; Fowler, Clare J; Elneil, Sohier

2008-01-01

To report our 10-year experience of sacral neurostimulation (SNS) for women in urinary retention, comparing the original one-stage with the newer two-stage technique, as SNS therapy is a well-established treatment for urinary retention secondary to urethral sphincter overactivity (Fowler's syndrome). Between 1996 and 2006, 60 patients with urinary retention had a SNS device inserted; their case records were reviewed and data on efficacy, follow-up, need for continued clean intermittent self-catheterization (CISC), complications and operative revision rate were assessed. Overall, 43 of 60 (72%) women were voiding spontaneously, with a mean postvoid residual volume of 100 mL; 30 (50%) no longer needed to use CISC. During a total of 2878 months of SNS experience, adverse event episodes included lead migration in 20, 'box-site' pain in 19, leg pain/numbness in 18 and loss of response/failure in 18 patients; 53% of the women required a surgical revision related to their implanted stimulator. The efficacy of the two-stage was similar to that of the one-stage procedure (73% vs 70%). Women with a normal urethral sphincter electromyogram had worse outcomes than women with an abnormal test (43% vs 76%). Although the efficacy was no different in those taking analgesia/antidepressant medication, this group of women had a higher surgical revision rate. Failure and complications for the one-stage procedure were not restricted to the early follow-up period. The mean battery life of the implant was 7.31 years. SNS has sustained long-term efficacy but the procedure has a significant complication rate. At present, the two-stage technique has comparable efficacy to the one-stage technique but a longer-term follow-up is required. The National Institute of Clinical Excellence recommended the use of SNS in women with urinary incontinence who fail to respond adequately to anticholinergic therapy, but patients choosing this treatment should be made aware of the high complication rate associated with the procedure.

Queer as F**k: Reaching and Engaging Gay Men in Sexual Health Promotion through Social Networking Sites

PubMed Central

Hellard, Margaret; Gold, Judy; Ata, Nadine; Chang, Shanton; Howard, Steve; Asselin, Jason; Ilic, Olivia; Batrouney, Colin; Stoove, Mark

2013-01-01

Background A growing number of health promotion interventions are taking advantage of the popularity and interactivity of new social media platforms to foster and engage communities for health promotion. However, few health promotion interventions using social networking sites (SNS) have been rigorously evaluated. "Queer as F**k"(QAF) began as pilot project in 2010 to deliver sexual health promotion via short "webisodes" on SNS to gay men. Now in its fifth season, QAF is among the few published examples internationally to demonstrate the sexual health promotion potential of SNS. Objective The objective of this evaluation is to assess reach, interactivity, and engagement generated by QAF to inform future health interventions and evaluations using SNS. Methods We undertook a mixed method process evaluation using an uncontrolled longitudinal study design that compared multiple measurements over time to assess changes in reach and engagement. We adapted evaluation methods from the health promotion, information systems, and creative spheres. We incorporated online usage statistics, interviews informed by user diary-scrapbooks, and user focus groups to assess intervention reach and engagement. Results During Series 1-3 (April 2010 to April 2011), 32 webisodes were posted on the QAF Facebook and YouTube pages. These webisodes attracted over 30,000 views; ranging from 124-3092 views per individual episode. By April 2011, the QAF Facebook page had 2929 predominantly male fans. Interview and focus group participants supported the balance of education and entertainment. They endorsed the narrative "soap opera" format as an effective way to deliver sexual health messages in an engaging, informative, and accessible manner that encouraged online peer discussion of sexual health and promoted community engagement. Conclusions QAF offers a successful example of exploiting the reach, interactivity, and engagement potential of SNS; findings from this process evaluation provide a model to inform the delivery and evaluation of future health promotion interventions on SNS. PMID:23391459

Queer as F**k: reaching and engaging gay men in sexual health promotion through social networking sites.

PubMed

Pedrana, Alisa; Hellard, Margaret; Gold, Judy; Ata, Nadine; Chang, Shanton; Howard, Steve; Asselin, Jason; Ilic, Olivia; Batrouney, Colin; Stoove, Mark

2013-02-07

A growing number of health promotion interventions are taking advantage of the popularity and interactivity of new social media platforms to foster and engage communities for health promotion. However, few health promotion interventions using social networking sites (SNS) have been rigorously evaluated. "Queer as F**k"(QAF) began as pilot project in 2010 to deliver sexual health promotion via short "webisodes" on SNS to gay men. Now in its fifth season, QAF is among the few published examples internationally to demonstrate the sexual health promotion potential of SNS. The objective of this evaluation is to assess reach, interactivity, and engagement generated by QAF to inform future health interventions and evaluations using SNS. We undertook a mixed method process evaluation using an uncontrolled longitudinal study design that compared multiple measurements over time to assess changes in reach and engagement. We adapted evaluation methods from the health promotion, information systems, and creative spheres. We incorporated online usage statistics, interviews informed by user diary-scrapbooks, and user focus groups to assess intervention reach and engagement. During Series 1-3 (April 2010 to April 2011), 32 webisodes were posted on the QAF Facebook and YouTube pages. These webisodes attracted over 30,000 views; ranging from 124-3092 views per individual episode. By April 2011, the QAF Facebook page had 2929 predominantly male fans. Interview and focus group participants supported the balance of education and entertainment. They endorsed the narrative "soap opera" format as an effective way to deliver sexual health messages in an engaging, informative, and accessible manner that encouraged online peer discussion of sexual health and promoted community engagement. QAF offers a successful example of exploiting the reach, interactivity, and engagement potential of SNS; findings from this process evaluation provide a model to inform the delivery and evaluation of future health promotion interventions on SNS.

Lack of α2C-Adrenoceptor Results in Contrasting Phenotypes of Long Bones and Vertebra and Prevents the Thyrotoxicosis-Induced Osteopenia

PubMed Central

Cruz Grecco Teixeira, Marilia Bianca; Martins, Gisele Miyamura; Miranda-Rodrigues, Manuela; De Araújo, Iasmin Ferreira; Oliveira, Ricardo; Brum, Patrícia Chakur; Azevedo Gouveia, Cecilia Helena

2016-01-01

A series of studies have demonstrated that activation of the sympathetic nervous system (SNS) causes osteopenia via β2-adrenoceptor (β2-AR) signaling. However, in a recent study, we found an unexpected and generalized phenotype of high bone mass in female mice with chronic sympathetic hyperactivity, due to double gene inactivation of adrenoceptors that negatively regulate norepinephrine release, α2A-and α2C-AR (α2A/2C-AR-/-). These findings suggest that β2-AR is not the single adrenoceptor involved in bone turnover regulation and show that α2-AR signaling may also mediate the SNS actions in the skeleton. In addition, we found that α2A/2C-AR-/- animals are resistant to the thyrotoxicosis-induced osteopenia, suggesting that thyroid hormone (TH), when in supraphysiological levels, interacts with the SNS to control bone mass and structure, and that this interaction may also involve α2-AR signaling. In the present study, to further investigate these hypotheses and to discriminate the roles of α2-AR subtypes, we have evaluated the bone phenotype of mice with the single gene inactivation of α2C-AR subtype, which mRNA expression was previously shown to be down regulated by triiodothyronine (T3). A cohort of 30 day-old female α2CAR-/- mice and their wild-type (WT) controls were treated with a supraphysiological dose of T3 for 30 or 90 days, which induced a thyrotoxic state in both mouse lineages. The micro-computed tomographic (μCT) analysis showed that α2C-AR-/- mice present lower trabecular bone volume (BV/TV) and number (Tb.N), and increased trabecular separation (Tb.Sp) in the femur compared with WT mice; which was accompanied by decreased bone strength (determined by the three-point bending test) in the femur and tibia. The opposite was observed in the vertebra, where α2C-AR-/- mice show increased BV/TV, Tb.N and trabecular thickness (Tb.Th), and decreased Tb.Sp, compared with WT animals. In spite of the contrasting bone phenotypes of the femur and L5, thyrotoxicosis negatively regulated most of the micro architectural features of the trabecular bone in both skeletal sites of WT, but not of α2C-AR-/- mice. T3 treatment also decreased biomechanical properties (maximum load and ultimate load) in the femur and tibia of WT, but not of knockout mice. The mRNA expression of osteocalcin, a marker of mature osteoblasts, and tartrate-resistant acid phosphatase, which is expressed by osteoclasts and is involved in collagen degradation, was increased by T3 treatment only in WT, and not in α2C-AR-/- mice. Altogether, these findings suggest that α2C-AR subtype mediates the effects of the SNS in the bone in a skeletal site-dependent manner, and that thyrotoxicosis depends on α2C-AR signaling to promote bone loss, which sustains the hypothesis of a TH-SNS interaction to modulate bone remodeling and structure. PMID:26815679

Lack of α2C-Adrenoceptor Results in Contrasting Phenotypes of Long Bones and Vertebra and Prevents the Thyrotoxicosis-Induced Osteopenia.

PubMed

Cruz Grecco Teixeira, Marilia Bianca; Martins, Gisele Miyamura; Miranda-Rodrigues, Manuela; De Araújo, Iasmin Ferreira; Oliveira, Ricardo; Brum, Patrícia Chakur; Azevedo Gouveia, Cecilia Helena

2016-01-01

A series of studies have demonstrated that activation of the sympathetic nervous system (SNS) causes osteopenia via β2-adrenoceptor (β2-AR) signaling. However, in a recent study, we found an unexpected and generalized phenotype of high bone mass in female mice with chronic sympathetic hyperactivity, due to double gene inactivation of adrenoceptors that negatively regulate norepinephrine release, α2A-and α2C-AR (α2A/2C-AR-/-). These findings suggest that β2-AR is not the single adrenoceptor involved in bone turnover regulation and show that α2-AR signaling may also mediate the SNS actions in the skeleton. In addition, we found that α2A/2C-AR-/- animals are resistant to the thyrotoxicosis-induced osteopenia, suggesting that thyroid hormone (TH), when in supraphysiological levels, interacts with the SNS to control bone mass and structure, and that this interaction may also involve α2-AR signaling. In the present study, to further investigate these hypotheses and to discriminate the roles of α2-AR subtypes, we have evaluated the bone phenotype of mice with the single gene inactivation of α2C-AR subtype, which mRNA expression was previously shown to be down regulated by triiodothyronine (T3). A cohort of 30 day-old female α2CAR-/- mice and their wild-type (WT) controls were treated with a supraphysiological dose of T3 for 30 or 90 days, which induced a thyrotoxic state in both mouse lineages. The micro-computed tomographic (μCT) analysis showed that α2C-AR-/- mice present lower trabecular bone volume (BV/TV) and number (Tb.N), and increased trabecular separation (Tb.Sp) in the femur compared with WT mice; which was accompanied by decreased bone strength (determined by the three-point bending test) in the femur and tibia. The opposite was observed in the vertebra, where α2C-AR-/- mice show increased BV/TV, Tb.N and trabecular thickness (Tb.Th), and decreased Tb.Sp, compared with WT animals. In spite of the contrasting bone phenotypes of the femur and L5, thyrotoxicosis negatively regulated most of the micro architectural features of the trabecular bone in both skeletal sites of WT, but not of α2C-AR-/- mice. T3 treatment also decreased biomechanical properties (maximum load and ultimate load) in the femur and tibia of WT, but not of knockout mice. The mRNA expression of osteocalcin, a marker of mature osteoblasts, and tartrate-resistant acid phosphatase, which is expressed by osteoclasts and is involved in collagen degradation, was increased by T3 treatment only in WT, and not in α2C-AR-/- mice. Altogether, these findings suggest that α2C-AR subtype mediates the effects of the SNS in the bone in a skeletal site-dependent manner, and that thyrotoxicosis depends on α2C-AR signaling to promote bone loss, which sustains the hypothesis of a TH-SNS interaction to modulate bone remodeling and structure.

76 FR 15818 - Airworthiness Directives; Reims Aviation S.A. Model F406 Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-22

... economic impact, positive or negative, on a substantial number of small entities under the criteria of the... numbers (SNs) 0002, 0003, 0004, 0006, 0008, 0009, 0010, 0012, 0013, 0017, 0024, 0025, 0039, 0042, 0044... Compliance (f) Unless already done, do the following actions: (1) For all affected SNs except F406-0091: (i...

76 FR 3854 - Airworthiness Directives; REIMS AVIATION S.A. Model F406 Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-21

... a substantial number of small entities under the criteria of the Regulatory Flexibility Act. We... Reims Aviation S.A. Model F406 airplanes, serial numbers (SNs) 0002, 0003, 0004, 0006, 0008, 0009, 0010... the following actions: (1) For all affected SNs except F406-0091: (i) Within the next 10 hours time-in...

Research on SNS and Education: The State of the Art and Its Challenges

ERIC Educational Resources Information Center

Rodríguez-Hoyos, Carlos; Haya Salmón, Ignacio; Fernández-Díaz, Elia

2015-01-01

This paper presents, for further discussion, a review of the scientific literature produced internationally on the use of Social Network Sites (SNS) in different levels of education and settings. A total of 62 articles published in international scientific journals with peer review have been analysed. The main objective of this paper is to discuss…

Preservice Teachers' Social Networking Use, Concerns, and Educational Possibilities: Trends from 2008 to 2012

ERIC Educational Resources Information Center

Hughes, Joan E.; Ko, Yujung; Lim, Mihyun; Liu, Sa

2015-01-01

This four-year, cross-sectional study, situated in one U.S. university, investigated 206 preservice teachers' use of social network services (SNS) in teacher preparation and their disposition toward using it in their future teaching. Using descriptive survey methodology, results revealed nearly all preservice teachers used a general SNS (e.g.,…

77 FR 5425 - Airworthiness Directives; Bell Helicopter Textron Canada Limited Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-03

.... Discussion Transport Canada (TC), which is the aviation authority for Canada, has issued AD CF-2010-32, dated..., serial numbers (S/Ns) 56001 through 56084, and S/Ns 58001 and 58002. TC advises that a review of the... 21.29 and the applicable bilateral agreement. Pursuant to the bilateral agreement, TC has kept the...

Cross Space: The Exploration of SNS-Based Writing Activities in a Multimodal Learning Environment

ERIC Educational Resources Information Center

Lee, Kwang-Soon; Kim, Bong-Gyu

2016-01-01

This study explores the positive learning effect of formulating English sentences via Social Network Service (SNS; "Kakao-Talk") on less proficient L2 university students' (LPSs') writing, when the application is utilized as a tool to link in and out-of class activities in a multimodal-learning environment. Its objective is also to…

Usefulness of Social Network Sites for Adolescents' Development of Online Career Skills

ERIC Educational Resources Information Center

Rutten, Mariëlle; Ros, Anje; Kuijpers, Marinka; Kreijns, Karel

2016-01-01

Schools have an important role in teaching students how to use Social Network Site (SNS) for career purposes. This involves the opportunity for students to practice online career skills. Different types of digital environments are available for schools. There are SNS designed to enable users to interact and network. In addition there are digital…

High-T(sub c) Superconductor-Normal-Superconductor Junctions with Polyimide-Passivated Ambient Temperature Edge Formation

NASA Technical Reports Server (NTRS)

Barner, J. B.; Kleinsasser, A. W.; Hunt, B. D.

1996-01-01

The ability to controllably fabricate High-Temperature Superconductor (HTS) S-Normal-S (SNS) Josephson Juntions (JJ's) enhances the possibilities fro many applications, including digital circuits, SQUID's, and mixers. A wide variety of approaches to fabricating SNS-like junctions has been tried and analyzed in terms of proximity effect behavior.

Preparation of SnS2 colloidal quantum dots and their application in organic/inorganic hybrid solar cells

PubMed Central

2011-01-01

Dispersive SnS2 colloidal quantum dots have been synthesized via hot-injection method. Hybrid photovoltaic devices based on blends of a conjugated polymer poly[2-methoxy-5-(3",7"dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV) as electron donor and crystalline SnS2 quantum dots as electron acceptor have been studied. Photoluminescence measurement has been performed to study the surfactant effect on the excitons splitting process. The photocurrent of solar cells with the hybrid depends greatly on the ligands exchange as well as the device heat treatment. AFM characterization has demonstrated morphology changes happening upon surfactant replacement and annealing, which can explain the performance variation of hybrid solar cells. PMID:21711811

Method Producing an SNS Superconducting Junction with Weak Link Barrier

NASA Technical Reports Server (NTRS)

Hunt, Brian D. (Inventor)

1999-01-01

A method of producing a high temperature superconductor Josephson element and an improved SNS weak link barrier element is provided. A YBaCuO superconducting electrode film is deposited on a substrate at a temperature of approximately 800 C. A weak link barrier layer of a nonsuperconducting film of N-YBaCuO is deposited over the electrode at a temperature range of 520 C. to 540 C. at a lower deposition rate. Subsequently a superconducting counter-electrode film layer of YBaCuO is deposited over the weak link barrier layer at approximately 800 C. The weak link barrier layer has a thickness of approximately 50 A and the SNS element can be constructed to provide an edge geometry junction.

Ignition and monitoring technique for plasma processing of multicell superconducting radio-frequency cavities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Doleans, Marc

In this study, an in-situ plasma processing technique has been developed at the Spallation Neutron Source (SNS) to improve the performance of the superconducting radio-frequency (SRF) cavities in operation. The technique uses a low-density reactive neon-oxygen plasma at room-temperature to improve the surface work function, to help remove adsorbed gases on the RF surface and to reduce its secondary emission yield. SNS SRF cavities are six-cell elliptical cavities and the plasma typically ignites in the cell where the electric field is the highest. This article will detail a technique that was developed to ignite and monitor the plasma in eachmore » cell of the SNS cavities.« less

Sulfide semiconductor materials prepared by high-speed electrodeposition and discussion of electrochemical reaction mechanism

NASA Astrophysics Data System (ADS)

Okamoto, Naoki; Kataoka, Kentaro; Saito, Takeyasu

2017-07-01

A manufacturing method for SnS using a one-step electrochemical technique was developed. The sulfide semiconductor was formed by electrodeposition using an aqueous bath at low temperatures. The sulfide semiconductor particles produced were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The highest current density at which SnS was formed was 1800 mA/cm2 at a bath temperature of 293 K, which is 36 times larger than that in a previous deposition process. Analysis of the chronoamperometric current-time transients indicated that in the potential range from -1100 to -2000 mV vs saturated calomel electrode (SCE), the electrodeposition of SnS can be explained by an instantaneous nucleation model.

Are Social Networking Sites Making Health Behavior Change Interventions More Effective? A Meta-Analytic Review.

PubMed

Yang, Qinghua

2017-03-01

The increasing popularity of social networking sites (SNSs) has drawn scholarly attention in recent years, and a large amount of efforts have been made in applying SNSs to health behavior change interventions. However, these interventions showed mixed results, with a large variance of effect sizes in Cohen's d ranging from -1.17 to 1.28. To provide a better understanding of SNS-based interventions' effectiveness, a meta-analysis of 21 studies examining the effects of health interventions using SNS was conducted. Results indicated that health behavior change interventions using SNS are effective in general, but the effects were moderated by health topic, methodological features, and participant features. Theoretical and practical implications of findings are discussed.

A SnS2-based photomemristor driven by sun

NASA Astrophysics Data System (ADS)

Dragoman, Mircea; Batiri, Mihail; Dinescu, Adrian; Ciobanu, Vladimir; Rusu, Emil; Dragoman, Daniela; Tiginyanu, Ion

2018-01-01

We demonstrate experimentally that a sample of a SnS2 layered semiconductor compound with the area of 1 cm2 and the thickness of 100 μm, contacted laterally by silver electrodes with the area of 1 mm2, acts naturally as a memristor device when illuminated by a sun simulator. Although the conductance of the device changes with the number of pulses or voltages sweeps, the current-voltage dependence is almost linear, showing only a very narrow but clearly pinched hysteresis, which is the main imprint of a memristor. This SnS2-based solid-state miniaturized photomemristor could be used for the implementation of all-optical neuromorphic circuits based on artificial neurons and synapses, oriented to learning algorithms of living organisms.

SNS Central Helium Liquefier spare Carbon Bed installation and commissioning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Degraff, Brian D.; Howell, Matthew P.; Kim, Sang-Ho

The Spallation Neutron Source (SNS) Central Helium Liquefier (CHL) at Oak Ridge National Laboratory (ORNL) has been without major operations downtime since operations were started back in 2006. This system utilizes a vessel filled with activated carbon as the final major component to remove oil vapor from the compressed helium circuit prior to insertion into the system's cryogenic cold box. The need for a spare carbon bed at SNS due to the variability of carbon media lifetime calculation to adsorption efficiency will be discussed. The fabrication, installation and commissioning of this spare carbon vessel will be presented. The novel planmore » for connecting the spare carbon vessel piping to the existing infrastructure will be presented.« less

Ignition and monitoring technique for plasma processing of multicell superconducting radio-frequency cavities

DOE PAGES

Doleans, Marc

2016-12-27

In this study, an in-situ plasma processing technique has been developed at the Spallation Neutron Source (SNS) to improve the performance of the superconducting radio-frequency (SRF) cavities in operation. The technique uses a low-density reactive neon-oxygen plasma at room-temperature to improve the surface work function, to help remove adsorbed gases on the RF surface and to reduce its secondary emission yield. SNS SRF cavities are six-cell elliptical cavities and the plasma typically ignites in the cell where the electric field is the highest. This article will detail a technique that was developed to ignite and monitor the plasma in eachmore » cell of the SNS cavities.« less

Crystal Structure of Hydrazinium Iodide by Neutron Diffraction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Campbell, Eric V.; Wang, Xiaoping; Miller, Joel S.

The structure of hydrazinium iodide, [H 5N 2] +·I -, at 100 K has monoclinic (P2 1/n) symmetry from single crystal neutron diffraction with a = 7.4599(7) Å, b = 5.3185(6) Å, c = 10.1628(11) Å, β = 103.150(10)°, V = 392.64(7) Å 3, Z = 4. The refinement converged to R = 0.0575, wR 2 = 0.1602, S = 1.022. Data for the crystal structure was collected on the SNS TOPAZ single-crystal time-of-flight Laue diffractometer. The compound has a one-dimensional structure which displays N–H···N hydrogen bonding. Finally, accurate intra- and intermolecular N–H distances have been determined.

Crystal Structure of Hydrazinium Iodide by Neutron Diffraction

DOE PAGES

Campbell, Eric V.; Wang, Xiaoping; Miller, Joel S.

2017-10-31

The structure of hydrazinium iodide, [H 5N 2] +·I -, at 100 K has monoclinic (P2 1/n) symmetry from single crystal neutron diffraction with a = 7.4599(7) Å, b = 5.3185(6) Å, c = 10.1628(11) Å, β = 103.150(10)°, V = 392.64(7) Å 3, Z = 4. The refinement converged to R = 0.0575, wR 2 = 0.1602, S = 1.022. Data for the crystal structure was collected on the SNS TOPAZ single-crystal time-of-flight Laue diffractometer. The compound has a one-dimensional structure which displays N–H···N hydrogen bonding. Finally, accurate intra- and intermolecular N–H distances have been determined.

Men are from Mars, women are from Venus? Examining gender differences in self-presentation on social networking sites.

PubMed

Haferkamp, Nina; Eimler, Sabrina C; Papadakis, Anna-Margarita; Kruck, Jana Vanessa

2012-02-01

Psychological research on gender differences in self-presentation has already revealed that women place higher priority on creating a positive self-presentation, while men are less concerned about the image they present in face-to-face (ftf) communication. Nowadays, with the extensive use of new media, self-presentation is no longer so closely tied to ftf situations, but can also take place in the online world. Specifically, social networking sites (SNS), such as Facebook or MySpace, offer various features such as profile pictures, groups, and virtual bulletin boards with which users can create elaborated online representations of themselves. What remains open is whether this virtual self-presentation on SNS is subject to gender differences. Based on studies emphasizing gender-related differences in Internet communication and behavior in general, it can be assumed that men and women have different motives regarding their SNS usage as well. A multimethodological study, combining results of an online survey and a content analysis of 106 user profiles, assessed users' diverse motives for participating in SNS in general, and their use of specific profile elements or self-presentation in particular. In this sample of StudiVZ users, women tend to be more likely to use SNS for comparing themselves with others and for searching for information. Men, on the other hand, are more likely to look at other people's profiles to find friends. Moreover, women tend to use group names for their self-presentation and prefer adding portrait photos to their profiles, while men choose full-body shots.

The viscoelastic standard nonlinear solid model: predicting the response of the lumbar intervertebral disk to low-frequency vibrations.

PubMed

Groth, Kevin M; Granata, Kevin P

2008-06-01

Due to the mathematical complexity of current musculoskeletal spine models, there is a need for computationally efficient models of the intervertebral disk (IVD). The aim of this study is to develop a mathematical model that will adequately describe the motion of the IVD under axial cyclic loading as well as maintain computational efficiency for use in future musculoskeletal spine models. Several studies have successfully modeled the creep characteristics of the IVD using the three-parameter viscoelastic standard linear solid (SLS) model. However, when the SLS model is subjected to cyclic loading, it underestimates the load relaxation, the cyclic modulus, and the hysteresis of the human lumbar IVD. A viscoelastic standard nonlinear solid (SNS) model was used to predict the response of the human lumbar IVD subjected to low-frequency vibration. Nonlinear behavior of the SNS model was simulated by a strain-dependent elastic modulus on the SLS model. Parameters of the SNS model were estimated from experimental load deformation and stress-relaxation curves obtained from the literature. The SNS model was able to predict the cyclic modulus of the IVD at frequencies of 0.01 Hz, 0.1 Hz, and 1 Hz. Furthermore, the SNS model was able to quantitatively predict the load relaxation at a frequency of 0.01 Hz. However, model performance was unsatisfactory when predicting load relaxation and hysteresis at higher frequencies (0.1 Hz and 1 Hz). The SLS model of the lumbar IVD may require strain-dependent elastic and viscous behavior to represent the dynamic response to compressive strain.

Infant Parasympathetic and Sympathetic Activity during Baseline, Stress and Recovery: Interactions with Prenatal Adversity Predict Physical Aggression in Toddlerhood.

PubMed

Suurland, J; van der Heijden, K B; Huijbregts, S C J; van Goozen, S H M; Swaab, H

2018-05-01

Exposure to prenatal adversity is associated with aggression later in life. Individual differences in autonomic nervous system (ANS) functioning, specifically nonreciprocal activation of the parasympathetic (PNS) and sympathetic (SNS) nervous systems, increase susceptibility to aggression, especially in the context of adversity. Previous work examining interactions between early adversity and ANS functioning in infancy is scarce and has not examined interaction between PNS and SNS. This study examined whether the PNS and SNS moderate the relation between cumulative prenatal risk and early physical aggression in 124 children (57% male). Cumulative risk (e.g., maternal psychiatric disorder, substance (ab)use, and social adversity) was assessed during pregnancy. Parasympathetic respiratory sinus arrhythmia (RSA) and sympathetic pre-ejection period (PEP) at baseline, in response to and during recovery from emotional challenge were measured at 6 months. Physical aggression and non-physical aggression/oppositional behavior were measured at 30 months. The results showed that cumulative prenatal risk predicted elevated physical aggression and non-physical aggression/oppositional behavior in toddlerhood; however, the effects on physical aggression were moderated by PNS and SNS functioning. Specifically, the effects of cumulative risk on physical aggression were particularly evident in children characterized by low baseline PNS activity and/or by nonreciprocal activity of the PNS and SNS, characterized by decreased activity (i.e., coinhibition) or increased activity (i.e., coactivation) of both systems at baseline and/or in response to emotional challenge. These findings extend our understanding of the interaction between perinatal risk and infant ANS functioning on developmental outcome.

Rapidly Synthesized, Few-Layered Pseudocapacitive SnS2 Anode for High-Power Sodium Ion Batteries.

PubMed

Thangavel, Ranjith; Samuthira Pandian, Amaresh; Ramasamy, Hari Vignesh; Lee, Yun-Sung

2017-11-22

The abundance of sodium resources has recently motivated the investigation of sodium ion batteries (SIBs) as an alternative to commercial lithium ion batteries. However, the low power and low capacity of conventional sodium anodes hinder their practical realization. Although most research has concentrated on the development of high-capacity sodium anodes, anodes with a combination of high power and high capacity have not been widely realized. Herein, we present a simple microwave irradiation technique for obtaining few-layered, ultrathin two-dimensional SnS 2 over graphene sheets in a few minutes. SnS 2 possesses a large number of active surface sites and exhibits high-capacity, rapid sodium ion storage kinetics induced by quick, nondestructive pseudocapacitance. Enhanced sodium ion storage at a high current density (12 A g -1 ), accompanied by high reversibility and high stability, was demonstrated. Additionally, a rationally designed sodium ion full cell coupled with SnS 2 //Na 3 V 2 (PO 4 ) 3 exhibited exceptional performance with high initial Coulombic efficiency (99%), high capacity, high stability, and a retention of ∼53% of the initial capacity even after the current density was increased by a factor of 140. In addition, a high specific energy of ∼140 Wh kg -1 and an ultrahigh specific power of ∼8.3 kW kg -1 (based on the mass of both the anode and cathode) were observed. Because of its outstanding performance and rapid synthesis, few-layered SnS 2 could be a promising candidate for practical realization of high-power SIBs.

Teachers' Attitude towards Special Need Students in Secondary Schools in North Senatorial District of Edo State, Nigeria

ERIC Educational Resources Information Center

Offor, Dianarose Iyeoma; Akinlosotu, Nathaniel Toyosi

2017-01-01

The study investigated attitude towards special need students (SNS) among teachers in public secondary schools in Edo Central Senatorial District. The study was undertaken to determine the teachers' attitude and the influence of gender, educational specialisation and experience on their attitude towards SNS. A total of 369 (50%) of the 739…

A Generational Comparison of Social Networking Site Use: The Influence of Age and Social Identity

ERIC Educational Resources Information Center

Barker, Valerie

2012-01-01

An online survey (N = 256) compared social networking site (SNS) use among younger (millennial: 18-29) and older (baby-boomer: 41-64) subscribers focusing on the influence of collective self-esteem and group identity on motives for SNS use. Younger participants reported higher positive collective self-esteem, social networking site use for peer…

A Study of How Young Adults Leverage Multiple Profile Management Functionality in Managing Their Online Reputation on Social Networking Sites

ERIC Educational Resources Information Center

McCune, T. John

2017-01-01

With privacy settings on social networking sites (SNS) perceived as complex and difficult to use and maintain, young adults can be left vulnerable to others accessing and using their personal information. Consequences of not regulating the boundaries their information on SNS include the ability for current and future employers to make…

Design Analysis of SNS Target StationBiological Shielding Monoligh with Proton Power Uprate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bekar, Kursat B.; Ibrahim, Ahmad M.

2017-05-01

This report documents the analysis of the dose rate in the experiment area outside the Spallation Neutron Source (SNS) target station shielding monolith with proton beam energy of 1.3 GeV. The analysis implemented a coupled three dimensional (3D)/two dimensional (2D) approach that used both the Monte Carlo N-Particle Extended (MCNPX) 3D Monte Carlo code and the Discrete Ordinates Transport (DORT) two dimensional deterministic code. The analysis with proton beam energy of 1.3 GeV showed that the dose rate in continuously occupied areas on the lateral surface outside the SNS target station shielding monolith is less than 0.25 mrem/h, which compliesmore » with the SNS facility design objective. However, the methods and codes used in this analysis are out of date and unsupported, and the 2D approximation of the target shielding monolith does not accurately represent the geometry. We recommend that this analysis is updated with modern codes and libraries such as ADVANTG or SHIFT. These codes have demonstrated very high efficiency in performing full 3D radiation shielding analyses of similar and even more difficult problems.« less

A Privacy Preservation Model for Health-Related Social Networking Sites.

PubMed

Li, Jingquan

2015-07-08

The increasing use of social networking sites (SNS) in health care has resulted in a growing number of individuals posting personal health information online. These sites may disclose users' health information to many different individuals and organizations and mine it for a variety of commercial and research purposes, yet the revelation of personal health information to unauthorized individuals or entities brings a concomitant concern of greater risk for loss of privacy among users. Many users join multiple social networks for different purposes and enter personal and other specific information covering social, professional, and health domains into other websites. Integration of multiple online and real social networks makes the users vulnerable to unintentional and intentional security threats and misuse. This paper analyzes the privacy and security characteristics of leading health-related SNS. It presents a threat model and identifies the most important threats to users and SNS providers. Building on threat analysis and modeling, this paper presents a privacy preservation model that incorporates individual self-protection and privacy-by-design approaches and uses the model to develop principles and countermeasures to protect user privacy. This study paves the way for analysis and design of privacy-preserving mechanisms on health-related SNS.

Text Messaging and Social Network Site Use to Facilitate Alcohol Involvement: A Comparison of U.S. and Korean College Students.

PubMed

Jensen, Michaeline; Hussong, Andrea M; Baik, Jeesook

2018-05-01

Alcohol-related content on public social networking sites (SNS) has been linked to collegiate alcohol use, but we know little about whether and how private forms of computer-mediated communication (CMC), like text messaging, are related to collegiate drinking, nor how alcohol-related CMC content and drinking are associated in non-Western cultures. We examined the ways in which private text messaging and SNS are used to facilitate alcohol involvement among U.S. (n = 575) and Korean (n = 462) college students (total N = 1037), two technologically wired cultures with prevalent collegiate alcohol misuse. Results show that college students prefer private text messaging over SNS to find parties and facilitate alcohol involvement, and this preference tends to be stronger in Korea than the United States. Private text messaging is more consistently and strongly associated with alcohol use frequency and heavy episodic drinking than SNS posts in both countries, with particularly robust associations between private text messaging and drinking in the United States. Findings underscore the role of CMCs in facilitating alcohol involvement and highlight the potential for analysis of private message content to further understand computer-mediated social processes in college student drinking.

Why do people move? Enhancing human mobility prediction using local functions based on public records and SNS data.

PubMed

Kim, Jungmin; Park, Juyong; Lee, Wonjae

2018-01-01

The quality of life for people in urban regions can be improved by predicting urban human mobility and adjusting urban planning accordingly. In this study, we compared several possible variables to verify whether a gravity model (a human mobility prediction model borrowed from Newtonian mechanics) worked as well in inner-city regions as it did in intra-city regions. We reviewed the resident population, the number of employees, and the number of SNS posts as variables for generating mass values for an urban traffic gravity model. We also compared the straight-line distance, travel distance, and the impact of time as possible distance values. We defined the functions of urban regions on the basis of public records and SNS data to reflect the diverse social factors in urban regions. In this process, we conducted a dimension reduction method for the public record data and used a machine learning-based clustering algorithm for the SNS data. In doing so, we found that functional distance could be defined as the Euclidean distance between social function vectors in urban regions. Finally, we examined whether the functional distance was a variable that had a significant impact on urban human mobility.

A systematic review of the impact of the use of social networking sites on body image and disordered eating outcomes.

PubMed

Holland, Grace; Tiggemann, Marika

2016-06-01

A large body of literature has demonstrated mass media effects on body image and disordered eating. More recently, research in this area has turned to 'new' forms of media, such as the Internet, and particularly Social Networking Sites (SNSs). A systematic search for peer-reviewed articles on SNS use and body image and eating disorders resulted in 20 studies meeting specific inclusion criteria. As a whole, these articles demonstrated that use of SNSs is associated with body image and disordered eating. Specific SNS activities, such as viewing and uploading photos and seeking negative feedback via status updates, were identified as particularly problematic. A small number of studies also addressed underlying processes and found that appearance-based social comparison mediated the relationship between SNS use and body image and eating concerns. Gender was not found to be a moderating factor. It was concluded that, although there is a good deal of correlational research supporting the maladaptive effect of SNS use on body image and disordered eating, more longitudinal and experimental studies are needed. Copyright © 2016 Elsevier Ltd. All rights reserved.

A Privacy Preservation Model for Health-Related Social Networking Sites

PubMed Central

2015-01-01

The increasing use of social networking sites (SNS) in health care has resulted in a growing number of individuals posting personal health information online. These sites may disclose users' health information to many different individuals and organizations and mine it for a variety of commercial and research purposes, yet the revelation of personal health information to unauthorized individuals or entities brings a concomitant concern of greater risk for loss of privacy among users. Many users join multiple social networks for different purposes and enter personal and other specific information covering social, professional, and health domains into other websites. Integration of multiple online and real social networks makes the users vulnerable to unintentional and intentional security threats and misuse. This paper analyzes the privacy and security characteristics of leading health-related SNS. It presents a threat model and identifies the most important threats to users and SNS providers. Building on threat analysis and modeling, this paper presents a privacy preservation model that incorporates individual self-protection and privacy-by-design approaches and uses the model to develop principles and countermeasures to protect user privacy. This study paves the way for analysis and design of privacy-preserving mechanisms on health-related SNS. PMID:26155953

The role of social networking sites in medical genetics research.

PubMed

Reaves, Allison Cook; Bianchi, Diana W

2013-05-01

Social networking sites (SNS) have potential value in the field of medical genetics as a means of research subject recruitment and source of data. This article examines the current role of SNS in medical genetics research and potential applications for these sites in future studies. Facebook is the primary SNS considered, given the prevalence of its use in the United States and role in a small but growing number of studies. To date, utilization of SNS in medical genetics research has been primarily limited to three studies that recruited subjects from populations of Facebook users [McGuire et al. (2009); Am J Bioeth 9: 3-10; Janvier et al. (2012); Pediatrics 130: 293-298; Leighton et al. (2012); Public Health Genomics 15: 11-21]. These studies and a number of other medical and public health studies that have used Facebook as a context for recruiting research subjects are discussed. Approaches for Facebook-based subject recruitment are identified, including paid Facebook advertising, snowball sampling, targeted searching and posting. The use of these methods in medical genetics research has the potential to facilitate cost-effective research on both large, heterogeneous populations and small, hard-to-access sub-populations. Copyright © 2013 Wiley Periodicals, Inc.

Ion Source Development at the SNS

NASA Astrophysics Data System (ADS)

Welton, R. F.; Stockli, M. P.; Murray, S. N.; Carr, J.; Carmichael, J.; Goulding, R. H.; Baity, F. W.

2007-08-01

The US Spallation Neutron Source (SNS) has recently begun producing neutrons and is currently on track to becoming a world-leading facility for material science based on neutron scattering. The facility is comprised of an H- ion source, a linear accelerator, an accumulator ring, a liquid-Hg target and a suite of neutron scattering instruments. Over the next several years the average H- current from the ion source will be increased in order to meet the baseline facility requirement of providing 1.4 MW of beam-power to the target and the SNS power upgrade power requirement of 2+ MW on target. Meeting the latter goal will require H- currents of 70-100 mA with an RMS emittance of 0.20-0.35 π mm mrad and a ˜7% duty-factor. To date, the RF-driven-multicusp SNS ion source has only been able to demonstrate sustained operation at 33 mA of beam current at a ˜7% duty-factor. This report details our efforts to develop variations of the current ion source which can meet these requirements. Designs and experimental results are presented for helicon plasma drivers, high-power external antennas, glow-discharge plasma guns and advanced Cs systems.

Energy Balanced Strategies for Maximizing the Lifetime of Sparsely Deployed Underwater Acoustic Sensor Networks

PubMed Central

Luo, Hanjiang; Guo, Zhongwen; Wu, Kaishun; Hong, Feng; Feng, Yuan

2009-01-01

Underwater acoustic sensor networks (UWA-SNs) are envisioned to perform monitoring tasks over the large portion of the world covered by oceans. Due to economics and the large area of the ocean, UWA-SNs are mainly sparsely deployed networks nowadays. The limited battery resources is a big challenge for the deployment of such long-term sensor networks. Unbalanced battery energy consumption will lead to early energy depletion of nodes, which partitions the whole networks and impairs the integrity of the monitoring datasets or even results in the collapse of the entire networks. On the contrary, balanced energy dissipation of nodes can prolong the lifetime of such networks. In this paper, we focus on the energy balance dissipation problem of two types of sparsely deployed UWA-SNs: underwater moored monitoring systems and sparsely deployed two-dimensional UWA-SNs. We first analyze the reasons of unbalanced energy consumption in such networks, then we propose two energy balanced strategies to maximize the lifetime of networks both in shallow and deep water. Finally, we evaluate our methods by simulations and the results show that the two strategies can achieve balanced energy consumption per node while at the same time prolong the networks lifetime. PMID:22399970

Atom-Thin SnS2-xSex with Adjustable Compositions by Direct Liquid Exfoliation from Single Crystals.

PubMed

Yang, Zhanhai; Liang, Hui; Wang, Xusheng; Ma, Xinlei; Zhang, Tao; Yang, Yanlian; Xie, Liming; Chen, Dong; Long, Yujia; Chen, Jitao; Chang, Yunjie; Yan, Chunhua; Zhang, Xinxiang; Zhang, Xueji; Ge, Binghui; Ren, Zhian; Xue, Mianqi; Chen, Genfu

2016-01-26

Two-dimensional (2D) chalcogenide materials are fundamentally and technologically fascinating for their suitable band gap energy and carrier type relevant to their adjustable composition, structure, and dimensionality. Here, we demonstrate the exfoliation of single-crystal SnS2-xSex (SSS) with S/Se vacancies into an atom-thin layer by simple sonication in ethanol without additive. The introduction of vacancies at the S/Se site, the conflicting atomic radius of sulfur in selenium layers, and easy incorporation with an ethanol molecule lead to high ion accessibility; therefore, atom-thin SSS flakes can be effectively prepared by exfoliating the single crystal via sonication. The in situ pyrolysis of such materials can further adjust their compositions, representing tunable activation energy, band gap, and also tunable response to analytes of such materials. As the most basic and crucial step of the 2D material field, the successful synthesis of an uncontaminated and atom-thin sample will further push ahead the large-scale applications of 2D materials, including, but not limited to, electronics, sensing, catalysis, and energy storage fields.

Synthesis of SnS nanoparticles by SILAR method for quantum dot-sensitized solar cells.

PubMed

Tsukigase, Hiroki; Suzuki, Yoshikazu; Berger, Marie-Hélène; Sagawa, Takashi; Yoshikawa, Susumu

2011-03-01

SnS-sensitized TiO2 electrodes were applied in quantum dot-sensitized solar cells (QDSSCs) which are environmentally more favorable than conventional Cd or Pb-chalcogenide-sensitized electrodes. SnS nanoparticles were well-distributed over the surface of TiO2 nanoparticles by the successive ionic layer adsorption and reaction (SILAR) method. Deposited SnS nanoparticles had diameter about 3 nm. Under AM1.5 irradiation with 100 mW/cm2 light intensity (at 1 sun), the energy conversion efficiency of obtained cells reached a value of 0.21% (0.25 cm2) at SILAR coating cycles of 5. In addition, the photovoltaic performance was improved by additional ZnS coating on the surface of SnS-sensitized TiO2 electrodes.

Nonradiative Energy Transfer from Individual CdSe/ZnS Quantum Dots to Single-Layer and Few-Layer Tin Disulfide

DOE PAGES

Zang, Huidong; Routh, Prahlad K.; Huang, Yuan; ...

2016-03-31

We study the combination of zero-dimensional (0D) colloidal CdSe/ZnS quantum dots with tin disulfide (SnS 2), a two-dimensional (2D)-layered metal dichalcogenide, results in 0D–2D hybrids with enhanced light absorption properties. These 0D–2D hybrids, when exposed to light, exhibit intrahybrid nonradiative energy transfer from photoexcited CdSe/ZnS quantum dots to SnS 2. Using single nanocrystal spectroscopy, we find that the rate for energy transfer in 0D–2D hybrids increases with added number of SnS 2 layers, a positive manifestation toward the potential functionality of such 2D-based hybrids in applications such as photovoltaics and photon sensing.

Nonradiative Energy Transfer from Individual CdSe/ZnS Quantum Dots to Single-Layer and Few-Layer Tin Disulfide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zang, Huidong; Routh, Prahlad K.; Huang, Yuan

We study the combination of zero-dimensional (0D) colloidal CdSe/ZnS quantum dots with tin disulfide (SnS 2), a two-dimensional (2D)-layered metal dichalcogenide, results in 0D–2D hybrids with enhanced light absorption properties. These 0D–2D hybrids, when exposed to light, exhibit intrahybrid nonradiative energy transfer from photoexcited CdSe/ZnS quantum dots to SnS 2. Using single nanocrystal spectroscopy, we find that the rate for energy transfer in 0D–2D hybrids increases with added number of SnS 2 layers, a positive manifestation toward the potential functionality of such 2D-based hybrids in applications such as photovoltaics and photon sensing.

Impact of Sodium Contamination in Tin Sulfide Thin-Film Solar Cells

DOE PAGES

Steinmann, Vera; Brandt, Riley E.; Chakraborty, Rupak; ...

2016-02-12

Empirical observations show that sodium(Na) is a benign contaminant in some thin-filmsolar cells. Here, we intentionally contaminate thermally evaporated tin sulfide (SnS)thin-films with sodium and measure the SnS absorber properties and solar cellcharacteristics. The carrier concentration increases from 2 × 10 16 cm -3 to 4.3 × 10 17 cm -3 in Na-doped SnSthin-films, when using a 13 nm NaCl seed layer, which is detrimental for SnS photovoltaic applications but could make Na-doped SnS an attractive candidate in thermoelectrics. We observed trends in carrier concentration and found that it is in good agreement with density functional theory calculations, which predictmore » an acceptor-type NaSn defect with low formation energy.« less

H- ion source developments at the SNSa)

NASA Astrophysics Data System (ADS)

Welton, R. F.; Stockli, M. P.; Murray, S. N.; Pennisi, T. R.; Han, B.; Kang, Y.; Goulding, R. H.; Crisp, D. W.; Sparks, D. O.; Luciano, N. P.; Carmichael, J. R.; Carr, J.

2008-02-01

The U.S. Spallation Neutron Source (SNS) will require substantially higher average and pulse H- beam currents than can be produced from conventional ion sources such as the base line SNS source. H- currents of 40-50mA (SNS operations) and 70-100mA (power upgrade project) with a rms emittance of 0.20-0.35πmmmrad and a ˜7% duty factor will be needed. We are therefore investigating several advanced ion source concepts based on rf plasma excitation. First, the performance characteristics of an external antenna source based on an Al2O3 plasma chamber combined with an external multicusp magnetic configuration, an elemental Cs system, and plasma gun will be discussed. Second, the first plasma measurements of a helicon-driven H- ion source will also be presented.

DEVELOPMENT OF TITANIUM NITRIDE COATING FOR SNS RING VACUUM CHAMBERS.

DOE Office of Scientific and Technical Information (OSTI.GOV)

HE,P.; HSEUH,H.C.; MAPES,M.

2001-06-18

The inner surface of the ring vacuum chambers of the US Spallation Neutron Source (SNS) will be coated with {approximately}100 nm of Titanium Nitride (TiN). This is to minimize the secondary electron yield (SEY) from the chamber wall, and thus avoid the so-called e-p instability caused by electron multipacting as observed in a few high-intensity proton storage rings. Both DC sputtering and DC-magnetron sputtering were conducted in a test chamber of relevant geometry to SNS ring vacuum chambers. Auger Electron Spectroscopy (AES) and Rutherford Back Scattering (RBS) were used to analyze the coatings for thickness, stoichiometry and impurity. Excellent resultsmore » were obtained with magnetron sputtering. The development of the parameters for the coating process and the surface analysis results are presented.« less

POWER SUPPLY CONTROL AND MONITORING FOR THE SNS RING AND TRANSPORT SYSTEM

DOE Office of Scientific and Technical Information (OSTI.GOV)

LAMBIASE,R.; OERTER,B.; PENG,S.

2001-06-28

There are approximately 300 magnet power supplies in the SNS accumulator ring and transport lines. Control and monitoring of the these converters will be primarily accomplished with a new Power Supply Interface and Controller (PSI/PSC) system developed for the SNS project. This PSI/PSC system provides all analog and digital commands and status readbacks in one fiber isolated module. With a maximum rate of 10KHz, the PSI/PSC must be supplemented with higher speed systems for the wide bandwidth pulsed injection supplies, and the even wider bandwidth extraction kickers. This paper describes the implementation of this PSI/PSC system, which was developed throughmore » an industry/laboratory collaboration, and the supplementary equipment used to support the wider bandwidth pulsed supplies.« less

The theory of spin noise spectroscopy: a review

DOE PAGES

Sinitsyn, Nikolai A.; Pershin, Yuriy V.

2016-09-12

Direct measurements of spin fluctuations are becoming the mainstream approach for studies of complex condensed matter, molecular, nuclear, and atomic systems. Our review covers recent progress in the field of optical spin noise spectroscopy (SNS) with an additional goal to establish an introduction into its theoretical foundations. Finally we used various theoretical techniques recently to interpret results of SNS measurements are explained alongside examples of their applications.

Security and Privacy Preservation in Human-Involved Networks

NASA Astrophysics Data System (ADS)

Asher, Craig; Aumasson, Jean-Philippe; Phan, Raphael C.-W.

This paper discusses security within human-involved networks, with a focus on social networking services (SNS). We argue that more secure networks could be designed using semi-formal security models inspired from cryptography, as well as notions like that of ceremony, which exploits human-specific abilities and psychology to assist creating more secure protocols. We illustrate some of our ideas with the example of the SNS Facebook.

Opinions of Students in Physical Education and Sports Teaching on the Use of Social Network Sites

ERIC Educational Resources Information Center

Herguner, Gulten

2011-01-01

Because an important period of time of daily life has been spent on the Internet, the way people communicate has recently changed. One of the most important reasons for this change is social network sites (SNS). It can be seen that the most adhesive users of SNS in Turkey which have gained an increasing global quality are students. This…

Working with Secondary School Leadership in a Large-Scale Reform in London, UK: Consultants' Perspectives of Their Role as Agents of School Change and Improvement

ERIC Educational Resources Information Center

Cameron, David Hagen

2010-01-01

This article uses a cultural and political theoretical framework to examine the relationship between consultants and secondary school leaders within a large-scale consultancy-based reform, the Secondary National Strategy (SNS), in London UK. The SNS follows a cascade model of implementation, in which nationally created initiatives are introduced…

Exploring Student Use of Social Networking Services (SNS) Surrounding Moral Development, Gender, Campus Crime, Safety, and the Clery Act: A Mixed Methods Study

ERIC Educational Resources Information Center

Baum, Haley

2017-01-01

The purpose of this explanatory sequential mixed methods study was to explore college students' use of social networking services (SNS); examining how and why they communicate about campus safety information. This study took place at Stockton University, a regional state institution in NJ. Undergraduate students took part in an online quantitative…

Sweat pore reactivity as a surrogate measure of sympathetic nervous system activity in trauma-exposed individuals with and without posttraumatic stress disorder.

PubMed

Familoni, Babajide O; Gregor, Kristin L; Dodson, Thomas S; Krzywicki, Alan T; Lowery, Bobby N; Orr, Scott P; Suvak, Michael K; Rasmusson, Ann M

2016-09-01

Stress analysis by FLIR (forward-looking infrared) evaluation (SAFE) has been demonstrated to monitor sweat pore activation (SPA) as a novel surrogate measure of sympathetic nervous system (SNS) activity in a normal population. SNS responses to a series of 15 1-s, 82 dB, white noise bursts were measured by skin conductance (SC) and SAFE monitoring of SPA on the fingers (FiP) and face (FaP) in 10 participants with posttraumatic stress disorder (PTSD) and 16 trauma-exposed participants without PTSD (Mage  = 48.92 ± 12.00 years; 26.9% female). Within participants, SC and FiP responses across trials were strongly correlated (r = .92, p < .001). Correlations between SC and FaP (r = .76, p = .001) and between FiP and FaP (r = .47, p = .005) were smaller. The habituation of SNS responses across the 15 trials was substantial (SC: d = -2.97; FiP: d = -2.34; FaP: d = -1.02). There was a strong correlation between habituation effects for SC and FiP (r = .76, p < .001), but not for SC and FaP (r = .15, p = .45) or FiP and FaP (r = .29, p = .16). Participants with PTSD showed larger SNS responses to the first loud noise than those without PTSD. PTSD reexperiencing symptoms assessed by the PTSD Checklist on the day of testing were associated with the SNS responses to the first loud noise measured by SC (d = 1.19) and FiP (d = .99), but not FaP (d = .10). This study confirms convergence of SAFE and SC as valid measures of SNS activity. SAFE FiP and SC responses were highly predictive of self-rated PTSD reexperiencing symptoms. SAFE may offer an attractive alternative for applications in PTSD and similar populations. © 2016 Society for Psychophysiological Research. This article has been contributed to by US Government employees and their work is in the public domain in the USA.

The influence of health-specific social network site use on the psychological well-being of cancer-affected people.

PubMed

Erfani, Seyedezahra Shadi; Blount, Yvette; Abedin, Babak

2016-05-01

We aimed to explore and examine how and in what ways the use of social network sites (SNSs) can improve health outcomes, specifically better psychological well-being, for cancer-affected people. Qualitative semi-structured interviews were conducted with users of the Ovarian Cancer Australia Facebook page (OCA Facebook), the exemplar SNS used in this study. Twenty-five women affected by ovarian cancer who were users of OCA Facebook were interviewed. A multi-theory perspective was employed to interpret the data. Most of the study participants used OCA Facebook daily. Some users were passive and only observed created content, while other users actively posted content and communicated with other members. Analysis showed that the use of this SNS enhanced social support for users, improved the users' experiences of social connectedness, and helped users learn and develop social presence, which ultimately improved their psychological well-being. The strong theoretical underpinning of our research and empirically derived results led to a new understanding of the capacity of SNSs to improve psychological well-being. Our study provides evidence showing how the integration of these tools into existing health services can enhance patients' psychological well-being. This study also contributes to the body of knowledge on the implications of SNS use for improving the psychological well-being of cancer-affected people. This research assessed the relationship between the use of SNSs, specifically OCA Facebook, and the psychological well-being of cancer-affected people. The study confirmed that using OCA Facebook can improve psychological well-being by demonstrating the potential value of SNSs as a support service in the healthcare industry. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Interfacial Interactions in Monolayer and Few-Layer SnS/CH3 NH3 PbI3 Perovskite van der Waals Heterostructures and Their Effects on Electronic and Optical Properties.

PubMed

Li, Jian-Cai; Wei, Zeng-Xi; Huang, Wei-Qing; Ma, Li-Li; Hu, Wangyu; Peng, Ping; Huang, Gui-Fang

2018-02-05

A high light-absorption coefficient and long-range hot-carrier transport of hybrid organic-inorganic perovskites give huge potential to their composites in solar energy conversion and environmental protection. Understanding interfacial interactions and their effects are paramount for designing perovskite-based heterostructures with desirable properties. Herein, we systematically investigated the interfacial interactions in monolayer and few-layer SnS/CH 3 NH 3 PbI 3 heterostructures and their effects on the electronic and optical properties of these structures by density functional theory. It was found that the interfacial interactions in SnS/CH 3 NH 3 PbI 3 heterostructures were van der Waals (vdW) interactions, and they were found to be insensitive to the layer number of 2D SnS sheets. Interestingly, although their band gap decreased upon increasing the layer number of SnS, the near-gap electronic states and optical absorption spectra of these heterostructures were found to be strikingly similar. This feature was determined to be critical for the design of 2D layered SnS-based heterostructures. Strong absorption in the ultraviolet and visible-light regions, type II staggered band alignment at the interface, and few-layer SnS as an active co-catalyst make 2D SnS/CH 3 NH 3 PbI 3 heterostructures promising candidates for photocatalysis, photodetectors, and solar energy harvesting and conversion. These results provide first insight into the nature of interfacial interactions and are useful for designing hybrid organic-inorganic perovskite-based devices with novel properties. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Dock mediates Scar- and WASp-dependent actin polymerization through interaction with cell adhesion molecules in founder cells and fusion-competent myoblasts.

PubMed

Kaipa, Balasankara Reddy; Shao, Huanjie; Schäfer, Gritt; Trinkewitz, Tatjana; Groth, Verena; Liu, Jianqi; Beck, Lothar; Bogdan, Sven; Abmayr, Susan M; Önel, Susanne-Filiz

2013-01-01

The formation of the larval body wall musculature of Drosophila depends on the asymmetric fusion of two myoblast types, founder cells (FCs) and fusion-competent myoblasts (FCMs). Recent studies have established an essential function of Arp2/3-based actin polymerization during myoblast fusion, formation of a dense actin focus at the site of fusion in FCMs, and a thin sheath of actin in FCs and/or growing muscles. The formation of these actin structures depends on recognition and adhesion of myoblasts that is mediated by cell surface receptors of the immunoglobulin superfamily. However, the connection of the cell surface receptors with Arp2/3-based actin polymerization is poorly understood. To date only the SH2-SH3 adaptor protein Crk has been suggested to link cell adhesion with Arp2/3-based actin polymerization in FCMs. Here, we propose that the SH2-SH3 adaptor protein Dock, like Crk, links cell adhesion with actin polymerization. We show that Dock is expressed in FCs and FCMs and colocalizes with the cell adhesion proteins Sns and Duf at cell-cell contact points. Biochemical data in this study indicate that different domains of Dock are involved in binding the cell adhesion molecules Duf, Rst, Sns and Hbs. We emphasize the importance of these interactions by quantifying the enhanced myoblast fusion defects in duf dock, sns dock and hbs dock double mutants. Additionally, we show that Dock interacts biochemically and genetically with Drosophila Scar, Vrp1 and WASp. Based on these data, we propose that Dock links cell adhesion in FCs and FCMs with either Scar- or Vrp1-WASp-dependent Arp2/3 activation.

Deprotonation/protonation of coordinated secondary thioamide units of pincer ruthenium complexes: modulation of voltammetric and spectroscopic characterization of the pincer complexes.

PubMed

Teratani, Takuya; Koizumi, Take-aki; Yamamoto, Takakazu; Tanaka, Koji; Kanbara, Takaki

2011-09-21

New pincer ruthenium complexes, [Ru(SCS)(tpy)]PF(6) (1) (SCS = 2,6-bis(benzylaminothiocarbonyl)phenyl), tpy = 2,2':6',2''-terpyridyl) and [Ru(SNS)(tpy)]PF(6) (2) (SNS = 2,5-bis(benzylaminothiocarbonyl)pyrrolyl), having κ(3)SCS and κ(3)SNS pincer ligands with two secondary thioamide units were synthesized by the reactions of [RuCl(3)(tpy)] with N,N'-dibenzyl-1,3-benzenedicarbothioamide (L1) and N,N'-dibenzyl-2,5-1H-pyrroledicarbothioamide (L2), respectively, and their chemical and electrochemical properties were elucidated. The structure of 1 was determined by X-ray crystallography. The complexes 1 and 2 showed a two-step deprotonation reaction by treatment with 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU), and the addition of DBU led to a shift of the metal-centered redox couples to a lower potential by 720 and 550 mV, respectively. The di-deprotonated complexes were also studied by (1)H-NMR and UV-vis spectroscopy. The addition of methanesulfonic acid (MSA) to the di-deprotonated complexes enabled the recovery of 1 and 2, indicating that the thioamide moiety underwent a reversible deprotonation-protonation process, which resulted in regulating the redox potentials of the metal center. The Pourbaix diagram of 1 revealed that 1 underwent a one-proton/one-electron transfer process in the pH range of 5.83-10.35, and a two-proton/one-electron process at a pH of over 10.35, indicating that the deprotonation/protonation process of the complexes is related to proton-coupled electron transfer (PCET). This journal is © The Royal Society of Chemistry 2011

Multi-Step Lithiation of Tin Sulfide: An Investigation Using In Situ Electron Microscopy

DOE PAGES

Hwang, Sooyeon; Yao, Zhenpeng; Zhang, Lei; ...

2018-04-03

Two-dimensional metal sulfides have been widely explored as promising electrodes for lithium ion batteries since their two-dimensional layered structure allows lithium ions to intercalate between layers. For tin disulfide, the lithiation process proceeds via a sequence of three different types of reactions: intercalation, conversion, and alloying but the full scenario of reaction dynamics remains nebulous. In this paper, we investigate the dynamical process of the multi-step reactions using in situ electron microscopy and discover an intermediate rock-salt phase with the disordering of Li and Sn cations, after the initial 2-dimensional intercalation. The disordered cations occupy all the octahedral sites andmore » block the channels for intercalation, which alter the reaction pathways during further lithiation. Our first principles calculations of the non-equilibrium lithiation of SnS2 corroborate the energetic preference of the disordered rock-salt structure over known layered polymorphs. The in situ observations and calculations suggest a two-phase reaction nature for intercalation, disordering, and following conversion reactions. In addition, in situ de-lithiation observation confirms that the alloying reaction is reversible while the conversion reaction is not, which is consistent to the ex situ analysis. This work reveals the full lithiation characteristic of SnS2 and sheds light on the understanding of complex multistep reactions in two-dimensional materials.« less

Multi-Step Lithiation of Tin Sulfide: An Investigation Using In Situ Electron Microscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hwang, Sooyeon; Yao, Zhenpeng; Zhang, Lei

Two-dimensional metal sulfides have been widely explored as promising electrodes for lithium ion batteries since their two-dimensional layered structure allows lithium ions to intercalate between layers. For tin disulfide, the lithiation process proceeds via a sequence of three different types of reactions: intercalation, conversion, and alloying but the full scenario of reaction dynamics remains nebulous. In this paper, we investigate the dynamical process of the multi-step reactions using in situ electron microscopy and discover an intermediate rock-salt phase with the disordering of Li and Sn cations, after the initial 2-dimensional intercalation. The disordered cations occupy all the octahedral sites andmore » block the channels for intercalation, which alter the reaction pathways during further lithiation. Our first principles calculations of the non-equilibrium lithiation of SnS2 corroborate the energetic preference of the disordered rock-salt structure over known layered polymorphs. The in situ observations and calculations suggest a two-phase reaction nature for intercalation, disordering, and following conversion reactions. In addition, in situ de-lithiation observation confirms that the alloying reaction is reversible while the conversion reaction is not, which is consistent to the ex situ analysis. This work reveals the full lithiation characteristic of SnS2 and sheds light on the understanding of complex multistep reactions in two-dimensional materials.« less

The sentinel lymph node spread determines quantitatively melanoma seeding to non-sentinel lymph nodes and survival.

PubMed

Ulmer, Anja; Dietz, Klaus; Werner-Klein, Melanie; Häfner, Hans-Martin; Schulz, Claudia; Renner, Philipp; Weber, Florian; Breuninger, Helmut; Röcken, Martin; Garbe, Claus; Fierlbeck, Gerhard; Klein, Christoph A

2018-03-01

Complete lymph node dissection (CLND) after a positive sentinel node (SN) biopsy provides important prognostic information in melanoma patients but has been questioned for therapeutic use recently. We explored whether quantification of the tumour spread to SNs may replace histopathology of non-sentinel nodes (NSNs) for staging purposes. We quantified melanoma spread in SNs and NSNs in 128 patients undergoing CLND for a positive SN. In addition to routine histopathology, one-half of each of all 1496 SNs and NSNs was disaggregated into a single cell suspension and stained immunocytochemically to determine the number of melanoma cells per 10 6 lymph node cells, i.e. the disseminated cancer cell density (DCCD). We uncovered melanoma spread to NSNs in the majority of patients; however, the tumour load and the proportion of positive nodes were significantly lower in NSNs than in SNs. The relation between SN and NSN spread could be described by a mathematical function with DCCD NSN  = DCCD SN c /10 1 - c (c = 0.69; 95% confidence interval [CI]: 0.62-0.76). At a median follow-up of 67 months, multivariable Cox regression analyses revealed that DCCD SN (p = 0.02; HR 1.34, 95% CI: 1.05-1.71) and the total number of pathologically positive nodes (p = 0.02; HR 1.53, 95% CI: 1.07-2.22) were significant risk factors after controlling for age, gender, thickness of melanoma and ulceration status. A prognostic model based on DCCD SN and melanoma thickness predicted outcome as accurately as a model including pathological information of both SNs and NSNs. The assessment of DCCD SN renders CLND for staging purposes unnecessary. Copyright © 2017 Elsevier Ltd. All rights reserved.

Preparedness for pandemics: does variation among states affect the nation as a whole?

PubMed

Potter, Margaret A; Brown, Shawn T; Lee, Bruce Y; Grefenstette, John; Keane, Christopher R; Lin, Chyongchiou J; Quinn, Sandra C; Stebbins, Samuel; Sweeney, Patricia M; Burke, Donald S

2012-01-01

Since states' public health systems differ as to pandemic preparedness, this study explored whether such heterogeneity among states could affect the nation's overall influenza rate. The Centers for Disease Control and Prevention produced a uniform set of scores on a 100-point scale from its 2008 national evaluation of state preparedness to distribute materiel from the Strategic National Stockpile (SNS). This study used these SNS scores to represent each state's relative preparedness to distribute influenza vaccine in a timely manner and assumed that "optimal" vaccine distribution would reach at least 35% of the state's population within 4 weeks. The scores were used to determine the timing of vaccine distribution for each state: each 10-point decrement of score below 90 added an additional delay increment to the distribution time. A large-scale agent-based computational model simulated an influenza pandemic in the US population. In this synthetic population each individual or agent had an assigned household, age, workplace or school destination, daily commute, and domestic intercity air travel patterns. Simulations compared influenza case rates both nationally and at the state level under 3 scenarios: no vaccine distribution (baseline), optimal vaccine distribution in all states, and vaccine distribution time modified according to state-specific SNS score. Between optimal and SNS-modified scenarios, attack rates rose not only in low-scoring states but also in high-scoring states, demonstrating an interstate spread of infections. Influenza rates were sensitive to variation of the SNS-modified scenario (delay increments of 1 day versus 5 days), but the interstate effect remained. The effectiveness of a response activity such as vaccine distribution could benefit from national standards and preparedness funding allocated in part to minimize interstate disparities.

Risk factors for testicular cancer--differences between pure non-seminoma and mixed seminoma/non-seminoma?

PubMed

Aschim, E L; Haugen, T B; Tretli, S; Daltveit, A K; Grotmol, T

2006-08-01

The origin of testicular germ cell cancer (TGCC) is believed to be carcinoma in situ cells developed in utero. Clinically, TGCCs are divided into two major histological groups, seminomas and non-seminomas, where the latter group includes non-seminomatous TGCCs with seminomatous components (mixed S/NS TGCC). Recent studies, however, have suggested that non-seminomas and mixed S/NS TGCCs could have certain differences in aetiology, and in this study the TGCCs were divided into three, rather than the conventional two histological groups. A large case-control study was undertaken on data on all live-born boys registered in the Medical Birth Registry of Norway during the period 1967-1998 (n=961 396). Among these were 1087 TGCC cases registered in the Cancer Registry of Norway until February 2004. We found several risk factors for TGCC, including low parity, low gestational age, epilepsy and retained placenta. Several of the variables studied seemed to be risk factors for specific histological groups, e.g. parity 0 vs. 2 and low gestational age being associated with increased risk of non-seminomas, but not of mixed S/NS TGCC, and low maternal age being associated with increased risk of mixed S/NS TGCC, but not of non-seminomatous TGCC. Therefore, our results might suggest that non-seminomas and mixed S/NS TGCCs have partially different risk factors, whose associations may be obscured by combining these two histological groups. The histological groups were not significantly different, however. Most of our findings on risk factors for TGCC are in agreement with at least some previous studies. An unexplainable exception is low birth weight being associated with reduced risk of TGCC in our study.

Deconstructing sub-clinical psychosis into latent-state and trait variables over a 30-year time span.

PubMed

Rössler, Wulf; Hengartner, Michael P; Ajdacic-Gross, Vladeta; Haker, Helene; Angst, Jules

2013-10-01

Our aim was to deconstruct the variance underlying the expression of sub-clinical psychosis symptoms into portions associated with latent time-dependent states and time-invariant traits. We analyzed data of 335 subjects from the general population of Zurich, Switzerland, who had been repeatedly measured between 1979 (age 20/21) and 2008 (age 49/50). We applied two measures of sub-clinical psychosis derived from the SCL-90-R, namely schizotypal signs (STS) and schizophrenia nuclear symptoms (SNS). Variance was decomposed with latent state-trait analysis and associations with covariates were examined with generalized linear models. At ages 19/20 and 49/50, the latent states underlying STS accounted for 48% and 51% of variance, whereas for SNS those estimates were 62% and 50%. Between those age classes, however, expression of sub-clinical psychosis was strongly associated with stable traits (75% and 89% of total variance in STS and SNS, respectively, at age 27/28). Latent states underlying variance in STS and SNS were particularly related to partnership problems over almost the entire observation period. STS was additionally related to employment problems, whereas drug-use was a strong predictor of states underlying both syndromes at age 19/20. The latent trait underlying expression of STS and SNS was particularly related to low sense of mastery and self-esteem and to high depressiveness. Although most psychosis symptoms are transient and episodic in nature, the variability in their expression is predominantly caused by stable traits. Those time-invariant and rather consistent effects are particularly influential around age 30, whereas the occasion-specific states appear to be particularly influential at ages 20 and 50. © 2013.

Factors associated with online victimisation among Malaysian adolescents who use social networking sites: a cross-sectional study

PubMed Central

Marret, Mary J; Choo, Wan Yuen

2017-01-01

Objective To determine the prevalence of online interpersonal victimisation and its association with patterns of social networking site (SNS) use, offline victimisation, offline perpetration and parental conflict among Malaysian adolescents using SNS. Methods A cross-sectional study of students from randomly selected public secondary schools in the state of Negeri Sembilan was conducted using an anonymous self-administered questionnaire. The questionnaire examined patterns of SNS use and included measures of online victimisation, online perpetration, offline victimisation and parental conflict. A response rate of 91% from a total of 1634 yielded a sample of 1487 students between 15 years and 16 years of age. Results Ninety-two per cent of respondents had used at least one SNS. More than half of SNS users (52.2%) reported experiences of online victimisation over the past 12 months. Boys were significantly more likely to experience online harassment compared with girls (52.2% vs 43.3%, p<0.001). There were no significant gender differences in experiences of unwanted sexual solicitation. Adolescents who engaged in perpetration behaviours online had almost six times higher odds of reporting frequent online victimisation compared with online behaviours involving personal disclosure. There was a significant dose-response relationship between engagement in multiple types of online behaviour and the risk of frequent online victimisation. Both online and offline perpetrations were associated with an increased risk of victimisation. Those who were victimised offline or experienced parental conflict were twice as likely to report online victimisation. Conclusion Interventions to prevent online electronic aggression should target perpetration behaviour both online and offline. Youth should be equipped with skills in communication and decision-making in relationships that can be applied across a spectrum of contexts both online and offline. PMID:28667209

Surface oxidation of tin chalcogenide nanocrystals revealed by 119Sn-Mössbauer spectroscopy.

PubMed

de Kergommeaux, Antoine; Faure-Vincent, Jérôme; Pron, Adam; de Bettignies, Rémi; Malaman, Bernard; Reiss, Peter

2012-07-18

Narrow band gap tin(II) chalcogenide (SnS, SnSe, SnTe) nanocrystals are of high interest for optoelectronic applications such as thin film solar cells or photodetectors. However, charge transfer and charge transport processes strongly depend on nanocrystals' surface quality. Using (119)Sn-Mössbauer spectroscopy, which is the most sensitive tool for probing the Sn oxidation state, we show that SnS nanocrystals exhibit a Sn((IV))/Sn((II)) ratio of around 20:80 before and 40:60 after five minutes exposure to air. Regardless of the tin or sulfur precursors used, similar results are obtained using six different synthesis protocols. The Sn((IV)) content before air exposure arises from surface related SnS(2) and Sn(2)S(3) species as well as from surface Sn atoms bound to oleic acid ligands. The increase of the Sn((IV)) content upon air exposure results from surface oxidation. Full oxidation of the SnS nanocrystals without size change is achieved by annealing at 500 °C in air. With the goal to prevent surface oxidation, SnS nanocrystals are capped with a cadmium-phosphonate complex. A broad photoluminescence signal centered at 600 nm indicates successful capping, which however does not reduce the air sensitivity. Finally we demonstrate that SnSe nanocrystals exhibit a very similar behavior with a Sn((IV))/Sn((II)) ratio of 43:57 after air exposure. In the case of SnTe nanocrystals, the ratio of 55:45 is evidence of a more pronounced tendency for oxidation. These results demonstrate that prior to their use in optoelectronics further surface engineering of tin chalcogenide nanocrystals is required, which otherwise have to be stored and processed under inert atmosphere.

Two dimensional disorder in black phosphorus and layered monochalcogenides

NASA Astrophysics Data System (ADS)

Barraza-Lopez, Salvador; Mehboudi, Mehrshad; Kumar, Pradeep; Harriss, Edmund O.; Churchill, Hugh O. H.; Dorio, Alex M.; Zhu, Wenjuan; van der Zande, Arend; Pacheco Sanjuan, Alejandro A.

The degeneracies of the structural ground state of materials with a layered orthorhombic structure such as black phosphorus and layered monochalcogenides GeS, GeSe, SnS, and SnSe, lead to an order/disorder transition in two dimensions at finite temperature. This transition has consequences on applications based on these materials requiring a crystalline two-dimensional structure. Details including a Potts model that explains the two-dimensional transition, among other results, will be given in this talk. References: M. Mehboudi, A.M. Dorio, W. Zhu, A. van der Zande, H.O.H. Churchill, A.A. Pacheco Sanjuan, E.O.H. Harris, P. Kumar, and S. Barraza-Lopez. arXiv:1510.09153.

Facing austerity: the decline in health access and quality of care for patients with cancer in Portugal.

PubMed

Barradas, Carlos da Silva; Nunes, João Arriscado

2017-01-01

In April 2011, Portugal called on the European Union for a financial bailout due to its debt crisis, and counterbalanced this rescue with various austerity measures. Within the Portuguese public health system (Serviço Nacional de Saúde, SNS) these measures were swiftly applied on a large scale, and in turn led to increasing difficulties among the health professionals within the SNS with regard to the use of diagnostics, treatments, and medications for patients, as well as growing obstacles to regular clinical consultations. Through media analysis of Portuguese health policy related to cancer and statements from professionals in the SNS, this article expresses the concerns of these health providers and explores how this situation is negatively impacting the lives of those who deal with this disease every day.

Personality and Social Influence Characteristic Affects on Ease of Use and Peer Influence of New Media Users Over Time

DTIC Science & Technology

2011-03-01

online social networking sites (SNSs) have emerged in today’s society as seen in the SNS Facebook and its over 500 million users. Millions of people...and locations through the social networking site ( SNS ) Facebook (Ghonim, 2011). Through the Facebook page created by Ghonim “We are all Khalid...1 Social Network Sites Defined ......................................................................................3 Purpose and

Sparsity and Nullity: Paradigm for Analysis Dictionary Learning

DTIC Science & Technology

2016-08-09

16. SECURITY CLASSIFICATION OF: Sparse models in dictionary learning have been successfully applied in a wide variety of machine learning and...we investigate the relation between the SNS problem and the analysis dictionary learning problem, and show that the SNS problem plays a central role...and may be utilized to solve dictionary learning problems. 1. REPORT DATE (DD-MM-YYYY) 4. TITLE AND SUBTITLE 13. SUPPLEMENTARY NOTES 12

A comparative analysis of anorexia nervosa groups on Facebook.

PubMed

Teufel, Martin; Hofer, Eva; Junne, Florian; Sauer, Helene; Zipfel, Stephan; Giel, Katrin Elisabeth

2013-12-01

To analyze the content and culture of anorexia nervosa (AN)-related communication on the current major social network site (SNS) Facebook. We searched for groups and sites related to AN on Facebook by means of a faux profile of a young female. Identified groups/sites were analyzed with respect to (1) category (education, self-help, professional help, pro-ana, anti pro-ana), (2) activity, (3) motivational aspects (prose, pictures), and (4) social support. Numerous relevant groups were found in all categories except that professional help was almost nonexistent. Pro-ana groups were found to be the most active, best organized, and offered the highest levels of social support. Prose motivation was distinctly offered in all categories. Motivation with pictures was particularly evident in pro-ana groups. The most functional motivation was found in self-help groups. SNS appears to be a relevant way for young females suffering from AN to communicate and exchange disease and health-related ideas. Caregivers, researchers, and institutions in the field of eating disorders should be aware of the existence, possibilities, dysfunctions, and influence of SNS. Whether SNS can help persons with AN to get therapeutic assistance as well as whether it can be integrated into psychotherapeutic strategies should be examined in future studies.

IRLT: Integrating Reputation and Local Trust for Trustworthy Service Recommendation in Service-Oriented Social Networks

PubMed Central

Liu, Zhiquan; Ma, Jianfeng; Jiang, Zhongyuan; Miao, Yinbin; Gao, Cong

2016-01-01

With the prevalence of Social Networks (SNs) and services, plenty of trust models for Trustworthy Service Recommendation (TSR) in Service-oriented SNs (S-SNs) have been proposed. The reputation-based schemes usually do not contain user preferences and are vulnerable to unfair rating attacks. Meanwhile, the local trust-based schemes generally have low reliability or even fail to work when the trust path is too long or does not exist. Thus it is beneficial to integrate them for TSR in S-SNs. This work improves the state-of-the-art Combining Global and Local Trust (CGLT) scheme and proposes a novel Integrating Reputation and Local Trust (IRLT) model which mainly includes four modules, namely Service Recommendation Interface (SRI) module, Local Trust-based Trust Evaluation (LTTE) module, Reputation-based Trust Evaluation (RTE) module and Aggregation Trust Evaluation (ATE) module. Besides, a synthetic S-SN based on the famous Advogato dataset is deployed and the well-known Discount Cumulative Gain (DCG) metric is employed to measure the service recommendation performance of our IRLT model with comparing to that of the excellent CGLT model. The results illustrate that our IRLT model is slightly superior to the CGLT model in honest environment and significantly outperforms the CGLT model in terms of the robustness against unfair rating attacks. PMID:26963089

Why do people move? Enhancing human mobility prediction using local functions based on public records and SNS data

PubMed Central

Park, Juyong

2018-01-01

The quality of life for people in urban regions can be improved by predicting urban human mobility and adjusting urban planning accordingly. In this study, we compared several possible variables to verify whether a gravity model (a human mobility prediction model borrowed from Newtonian mechanics) worked as well in inner-city regions as it did in intra-city regions. We reviewed the resident population, the number of employees, and the number of SNS posts as variables for generating mass values for an urban traffic gravity model. We also compared the straight-line distance, travel distance, and the impact of time as possible distance values. We defined the functions of urban regions on the basis of public records and SNS data to reflect the diverse social factors in urban regions. In this process, we conducted a dimension reduction method for the public record data and used a machine learning-based clustering algorithm for the SNS data. In doing so, we found that functional distance could be defined as the Euclidean distance between social function vectors in urban regions. Finally, we examined whether the functional distance was a variable that had a significant impact on urban human mobility. PMID:29432440

Surface functionalized Cu2Zn1- x Cd x SnS4 quinternary alloyed nanostructure for DNA sensing

NASA Astrophysics Data System (ADS)

Ibraheam, A. S.; Al-Douri, Y.; Voon, C. H.; Foo, K. L.; Azizah, N.; Gopinath, S. C. B.; Ameri, M.; Ibrahim, Sattar S.

2017-03-01

A sensing plate of extended Cu2Zn1- x Cd x SnS4 quinternary alloy nanostructures, fabricated on an oxidized silicon substrate by the sol-gel method, is reported in this paper. The fabricated device was characterized and analyzed via field emission-scanning electron microscopy, X-ray diffraction (XRD), and photoluminescence (PL). The XRD peaks shifted towards the lower angle side alongside increasing concentration of cadmium. The average diameter of the Cu2Zn1- x Cd x SnS4 quinternary alloy nanostructures falls between 21.55 and 43.12 nm, while the shift of the PL bandgap was from 1.81 eV ( x = 0) to 1.72 eV ( x = 1). The resulting Cu2Zn1- x Cd x SnS4 quinternary alloy nanostructures components were functionalized with oligonucleotides probe DNA molecules and interacted with the target, exhibiting good sensing capabilities due to its large surface-to-volume ratio. The fabrication, immobilization, and hybridization processes were analyzed via representative current-voltage ( I- V) plots. Its electrical profile shows that the device is capable to distinguish biomolecules. Its high performance was evident from the linear relationship between the probe DNA from cervical cancer and the target DNA, showing its applicability for medical applications.

Sympathetic Nervous System Modulation of Inflammation and Remodeling in the Hypertensive Heart

PubMed Central

Levick, Scott P.; Murray, David B.; Janicki, Joseph S.; Brower, Gregory L.

2010-01-01

Chronic activation of the sympathetic nervous system (SNS) is a key component of cardiac hypertrophy and fibrosis. However, previous studies have provided evidence to also implicate inflammatory cells, including mast cells, in the development of cardiac fibrosis. The current study investigated the potential interaction of cardiac mast cells with the SNS. Eight week old male SHR were sympathectomized to establish the effect of the SNS on cardiac mast cell density, myocardial remodeling and cytokine production in the hypertensive heart. Age-matched WKY served as controls. Cardiac fibrosis and hypertension were significantly attenuated and left ventricular mass normalized while cardiac mast cell density was markedly increased in sympathectomized SHR. Sympathectomy normalized myocardial levels of IFN-γ, IL-6 and IL-10, but had no effect on IL-4. The effect of norepinephrine and substance P on isolated cardiac mast cell activation was investigated as potential mechanisms of interaction between the two. Only substance P elicited mast cell degranulation. Substance P was also shown to induce the production of angiotensin II by a mixed population of isolated cardiac inflammatory cells, including mast cells, lymphocytes and macrophages. These results demonstrate the ability of neuropeptides to regulate inflammatory cell function, providing a potential mechanism by which the SNS and afferent nerves may interact with inflammatory cells in the hypertensive heart. PMID:20048196

Detection of sentinel lymph nodes in patients with early stage cervical cancer.

PubMed

Seong, Seok Ju; Park, Hyun; Yang, Kwang Moon; Kim, Tae Jin; Lim, Kyung Taek; Shim, Jae Uk; Park, Chong Taik; Lee, Ki Heon

2007-02-01

The purpose of this study was to determine the feasibility of identifying the sentinel lymph nodes (SNs) as well as to evaluate factors that might influence the SN detection rate in patients with cervical cancer of the uterus. Eighty nine patients underwent intracervical injection of 1% isosulfan blue dye at the time of planned radical hysterectomy and lymphadenectomy between January 2003 and December 2003. With the visual detection of lymph nodes that stained blue, SNs were identified and removed separately. Then all patients underwent complete pelvic lymph node dissection and/or para-aortic lymph node dissection. SNs were identified in 51 of 89 (57.3%) patients. The most common site for SN detection was the external iliac area. Metastatic nodes were detected in 21 of 89 (23.5%) patients. One false negative SN was obtained. Successful SN detection was more likely in patients younger than 50 yr (p=0.02) and with a history of preoperative conization (p=0.05). However, stage, histological type, surgical procedure and neoadjuvant chemotherapy showed no significant difference for SN detection rate. Therefore, the identification of SNs with isosulfan blue dye is feasible and safe. The SN detection rate was high in patients younger than 50 yr or with a history of preoperative conization.

Factors affecting satisfaction with cancer information provided through the social networking services of the National Cancer Information Center in Korea.

PubMed

Kye, Su Yeon; Lee, Min Hee; Yoo, Jisu; Oh, Kyung Hee; Jun, Jae Kwan

2017-01-01

This study aimed to identify the characteristics of social networking service (SNS) users and to assess the relationship of those factors to user satisfaction with the SNSs of the National Cancer Information Center (NCIC) in South Korea. A Web-based survey was completed by 1,670 users of the NCIC SNSs, who provided data on the sources they consulted for information about cancer, determinants of SNS use, sources of NCIC SNS awareness, the time of day they used the SNS, and their satisfaction level. Facebook users mainly became aware of the NCIC SNSs through an acquaintance's recommendation, while Twitter was accessed through other SNSs or blogs. Users in their 30s were less satisfied with the NCIC SNSs than those in their teens and 20s. Browsing for cancer-related information on the Internet, prioritizing information quality, and engaging in active use were related to a high level of satisfaction with the NCIC SNSs. Individuals who were exposed to the NCIC SNSs through other SNSs or printed materials were less satisfied with their experience of the NCIC SNSs than those who received a recommendation from an acquaintance. These findings may act as a catalyst to guide public health agencies to enhance their use of SNSs.

Taking stress response out of the box: stability, discontinuity, and temperament effects on HPA and SNS across social stressors in mother-infant dyads.

PubMed

Laurent, Heidemarie K; Ablow, Jennifer C; Measelle, Jeffrey

2012-01-01

This study investigated continuity and stability of hypothalamic-pituitary-adrenal (HPA) and sympathetic nervous system (SNS) response measures in mother-infant dyads across 2 different types of social stress sessions. Synchrony of response trajectories across systems (SNS-HPA coordination) and partners (mother-infant attunement) was addressed, as were associations with infant temperament. Primiparous mothers and their 18-month-old infants (n = 86 dyads) completed an attachment stressor--Strange Situation (Ainsworth, Blehar, Waters, & Wall, 1978)--at Session 1 and challenge stressors--cleanup task and emotion task battery--at Session 2. Mother and infant saliva samples collected to index pre-stress, stress, and post-stress response during each session were assayed for cortisol (HPA marker) and salivary alpha-amylase (sAA; SNS marker). Multilevel modeling of cortisol/sAA trajectories across sessions revealed rank-order stability in mother/infant stress measures but discontinuity in absolute levels; cortisol trajectories were higher during attachment stress, and sAA trajectories were higher during challenge stress. Varying degrees of mother-infant attunement were found across sessions/systems. Infant surgency predicted higher stress measures, and negative affect and effortful control predicted lower stress measures, though associations depended on session/system. Findings are discussed in terms of advancing a multisystemic, contextual definition of developing stress responsiveness.

Fish oil intake induces UCP1 upregulation in brown and white adipose tissue via the sympathetic nervous system.

PubMed

Kim, Minji; Goto, Tsuyoshi; Yu, Rina; Uchida, Kunitoshi; Tominaga, Makoto; Kano, Yuriko; Takahashi, Nobuyuki; Kawada, Teruo

2015-12-17

Brown adipose tissue (BAT) plays a central role in regulating energy homeostasis, and may provide novel strategies for the treatment of human obesity. BAT-mediated thermogenesis is regulated by mitochondrial uncoupling protein 1 (UCP1) in classical brown and ectopic beige adipocytes, and is controlled by sympathetic nervous system (SNS). Previous work indicated that fish oil intake reduces fat accumulation and induces UCP1 expression in BAT; however, the detailed mechanism of this effect remains unclear. In this study, we investigated the effect of fish oil on energy expenditure and the SNS. Fish oil intake increased oxygen consumption and rectal temperature, with concomitant upregulation of UCP1 and the β3 adrenergic receptor (β3AR), two markers of beige adipocytes, in the interscapular BAT and inguinal white adipose tissue (WAT). Additionally, fish oil intake increased the elimination of urinary catecholamines and the noradrenaline (NA) turnover rate in interscapular BAT and inguinal WAT. Furthermore, the effects of fish oil on SNS-mediated energy expenditure were abolished in transient receptor potential vanilloid 1 (TRPV1) knockout mice. In conclusion, fish oil intake can induce UCP1 expression in classical brown and beige adipocytes via the SNS, thereby attenuating fat accumulation and ameliorating lipid metabolism.

Fish oil intake induces UCP1 upregulation in brown and white adipose tissue via the sympathetic nervous system

PubMed Central

Kim, Minji; Goto, Tsuyoshi; Yu, Rina; Uchida, Kunitoshi; Tominaga, Makoto; Kano, Yuriko; Takahashi, Nobuyuki; Kawada, Teruo

2015-01-01

Brown adipose tissue (BAT) plays a central role in regulating energy homeostasis, and may provide novel strategies for the treatment of human obesity. BAT-mediated thermogenesis is regulated by mitochondrial uncoupling protein 1 (UCP1) in classical brown and ectopic beige adipocytes, and is controlled by sympathetic nervous system (SNS). Previous work indicated that fish oil intake reduces fat accumulation and induces UCP1 expression in BAT; however, the detailed mechanism of this effect remains unclear. In this study, we investigated the effect of fish oil on energy expenditure and the SNS. Fish oil intake increased oxygen consumption and rectal temperature, with concomitant upregulation of UCP1 and the β3 adrenergic receptor (β3AR), two markers of beige adipocytes, in the interscapular BAT and inguinal white adipose tissue (WAT). Additionally, fish oil intake increased the elimination of urinary catecholamines and the noradrenaline (NA) turnover rate in interscapular BAT and inguinal WAT. Furthermore, the effects of fish oil on SNS-mediated energy expenditure were abolished in transient receptor potential vanilloid 1 (TRPV1) knockout mice. In conclusion, fish oil intake can induce UCP1 expression in classical brown and beige adipocytes via the SNS, thereby attenuating fat accumulation and ameliorating lipid metabolism. PMID:26673120

IRLT: Integrating Reputation and Local Trust for Trustworthy Service Recommendation in Service-Oriented Social Networks.

PubMed

Liu, Zhiquan; Ma, Jianfeng; Jiang, Zhongyuan; Miao, Yinbin; Gao, Cong

2016-01-01

With the prevalence of Social Networks (SNs) and services, plenty of trust models for Trustworthy Service Recommendation (TSR) in Service-oriented SNs (S-SNs) have been proposed. The reputation-based schemes usually do not contain user preferences and are vulnerable to unfair rating attacks. Meanwhile, the local trust-based schemes generally have low reliability or even fail to work when the trust path is too long or does not exist. Thus it is beneficial to integrate them for TSR in S-SNs. This work improves the state-of-the-art Combining Global and Local Trust (CGLT) scheme and proposes a novel Integrating Reputation and Local Trust (IRLT) model which mainly includes four modules, namely Service Recommendation Interface (SRI) module, Local Trust-based Trust Evaluation (LTTE) module, Reputation-based Trust Evaluation (RTE) module and Aggregation Trust Evaluation (ATE) module. Besides, a synthetic S-SN based on the famous Advogato dataset is deployed and the well-known Discount Cumulative Gain (DCG) metric is employed to measure the service recommendation performance of our IRLT model with comparing to that of the excellent CGLT model. The results illustrate that our IRLT model is slightly superior to the CGLT model in honest environment and significantly outperforms the CGLT model in terms of the robustness against unfair rating attacks.

Reception thresholds for sentences in quiet, continuous noise, and interrupted noise in school-age children.

PubMed

Stuart, Andrew

2008-02-01

Sentence recognition in noise was employed to investigate the development of temporal resolution in school-age children. Eighty children aged 6 to 15 years and 16 young adults participated. Reception thresholds for sentences (RTSs) were determined in quiet and in backgrounds of competing continuous and interrupted noise. In the noise conditions, RTSs were determined with a fixed noise level. RTSs were higher in quiet for six- to seven-year-old children (p = .006). Performance was better in the interrupted noise evidenced by lower RTS signal-to-noise ratios (S/Ns) relative to continuous noise (p < .0001). An effect of age was found in noise (p < .0001) where RTS S/Ns decreased with increasing age. Specifically, children under 14 years performed worse than adults. "Release from masking" was computed by subtracting RTS S/Ns in interrupted noise from continuous noise for each participant. There was no significant difference in RTS S/N difference scores as a function of age (p = .057). Children were more adversely affected by noise and needed greater S/Ns in order to perform as well as adults. Since there was no effect of age on the amount of release from masking, one can suggest that school-age children have inherently poorer processing efficiency rather than temporal resolution.

Elaboration of leadership and culture in high-performing nursing units of hospitals as perceived by staff nurses.

PubMed

Casida, Jesus M; Crane, Patrick C; Walker, Tara L; Wargo, Lisa M

2012-01-01

The leadership-culture phenomenon, a known explanatory construct for organizational performance, is understudied in nursing. Building on our previous work, we further addressed this knowledge gap through explorations of demographics and hospital variables which may have a significant influence on staff nurses' (SNs) perceptions of their nurse managers' (NMs) leadership and nursing unit culture. Furthermore, we explored the extent to which the NMs' leadership predicted specific cultures which typify nursing unit effectiveness. Using dissertation data provided by278 SNs, we found that SNs educated at the baccalaureate level or higher had favorable perceptions of their nursing unit performance and viewed their NMs' leadership differently than the SNs with diploma or associate degrees. The frequent portrayals of transformational (TFL) leadership behaviors (e.g., visionary) by the NMs were paramount in shaping culture traits which exemplify high performance outcomes. TFL leaders were more likely to shape unit cultures which are flexible and adaptive to the environmental challenges within and outside the nursing unit. Thus, the type of NMs' leadership and unit culture may provide an added value in explaining the performance level in patient care units which consequently affects the overall hospital/organizational outcomes. Implications for research and leadership practices are presented.

Use of social networking sites and associations with skin tone dissatisfaction, sun exposure, and sun protection in a sample of Australian adolescents.

PubMed

Mingoia, John; Hutchinson, Amanda D; Gleaves, David H; Corsini, Nadia; Wilson, Carlene

2017-12-01

Previous research has indicated that greater exposure to traditional media (i.e. television, film, and print) predicted skin cancer risk factors in adolescents; however, the relationship between social media usage and these outcomes remains unexplored. We examined whether social networking site (SNS) usage, and the particular manner of this use, was associated with skin tone dissatisfaction, sun exposure and sun protection among Australian adolescents. We also explored sex differences in SNS usage related to tanning. A total of 1856 South Australian secondary school students completed the Australian School Students Alcohol and Drug 2014 survey. SNS usage related to tanning comprised posting pictures, posting text, viewing pictures, viewing text and liking or sharing posts. Adolescents spent 214.56 minutes, on average, per day using SNSs. Behaviours related to tanning that involved pictures (i.e. viewing pictures, posting pictures, and liking or sharing content) were significantly associated with more skin tone dissatisfaction, more sun exposure and less sun protection. Females performed all SNS-linked behaviours more frequently than did males, with the exception of posting text. Australian adolescents spend a considerable amount of time using SNSs, and their behaviours related to tanning on these SNSs are significantly associated with skin cancer risk factors.

ASCA Observations of LMC SNRS

NASA Technical Reports Server (NTRS)

Hughes, John P.

1999-01-01

We present our first results from a study of the supernova remnants (SNRs) in the Large Magellanic Cloud (LMC) using data from ASCA. The three remnants we have analyzed to date, 0509-67.5, 0519-69.0, and N103B, are among the smallest, and presumably also the youngest, in the Cloud. The X-ray spectra of these SNRs show strong K(alpha) emission lines of silicon, sulfur, argon, and calcium with no evidence for corresponding lines of oxygen, neon, or magnesium. The dominant feature in the spectra is a broad blend of emission lines around 1 keV which we attribute to L-shell emission lines of iron. Model calculations (Nomoto, Thielemann, & Yokoi 1984) show that the major products of nucleosynthesis in Type Ia supernovae (SNs) are the elements from silicon to iron, as observed here. The calculated nucleosynthetic yields from Type Ib and II SNs are shown to be qualitatively inconsistent with the data. We conclude that the SNs which produced these remnants were of Type Ia. This finding also confirms earlier suggestions that the class of Balmer-dominated remnants arise from Type Ia SN explosions. Based an these early results from the LMC SNR sample, we find that roughly one-half of the SNRs produced in the LMC within the last approximately 1500 yr came from Type Ia SNs.

Differentiation in the angiotensin II receptor 1 blocker class on autonomic function.

PubMed

Krum, H

2001-09-01

Autonomic function is disordered in cardiovascular disease states such as chronic heart failure (CHF) and hypertension. Interactions between the renin-angiotensin-aldosterone system (RAAS) and the sympathetic nervous system (SNS) may potentially occur at a number of sites. These include central sites (eg, rostral ventrolateral medulla), at the level of baroreflex control, and at the sympathetic prejunctional angiotensin II receptor 1 (AT(1)) receptor, which is facilitatory for norepinephrine release from the sympathetic nerve terminal. Therefore, drugs that block the RAAS may be expected to improve autonomic dysfunction in cardiovascular disease states. In order to test the hypothesis that RAAS inhibition directly reduces SNS activity, a pithed rat model of sympathetic stimulation has been established. In this model, an increase in frequency of stimulation results in a pressor response that is sympathetically mediated and highly reproducible. This pressor response is enhanced in the presence of angiotensin II and is reduced in the presence of nonselective AIIRAs that block both AT(1) and AT(2) receptor subtypes (eg, saralasin). AT(1)-selective antagonists have also been studied in this model, at pharmacologically relevant doses. In one such study, only the AT(1) blocker eprosartan reduced sympathetically stimulated increases in blood pressure, whereas comparable doses of losartan, valsartan, and irbesartan did not. The reason(s) for the differences between eprosartan and other agents of this class on sympathetic modulation are not clear, but may relate to the chemical structure of the drug (a non- biphenyl tetrazole structure that is chemically distinct from the structure of other AIIRAs), receptor binding characteristics (competitive), or unique effects on presynaptic AT(1) receptors.

Electron-cloud updated simulation results for the PSR, and recent results for the SNS

NASA Astrophysics Data System (ADS)

Pivi, M.; Furman, M. A.

2002-05-01

Recent simulation results for the main features of the electron cloud in the storage ring of the Spallation Neutron Source (SNS) at Oak Ridge, and updated results for the Proton Storage Ring (PSR) at Los Alamos are presented in this paper. A refined model for the secondary emission process including the so called true secondary, rediffused and backscattered electrons has recently been included in the electron-cloud code.

Improving older people's life satisfaction via social networking site use: Evidence from China.

PubMed

Zhou, Junjie

2018-03-01

This study aimed to examine the pathways by which social networking sites (SNSs) can improve older people's life satisfaction. We conducted an online survey in China that lasted eight weeks. Respondents were required to report their demographic characteristics and feelings regarding SNS use. Data were analysed using SPSS 20 and Amos 21. We collected 596 valid samples. The empirical results show that SNS use improves older people's life satisfaction by reducing their loneliness and improving their self-efficacy. Social support alleviates the negative effect of loneliness and enhances the positive effect of self-efficacy on life satisfaction. Sex differences and education differences were significant. Men and less educated people had higher levels of life satisfaction. Policymakers should offer support to SNSs targeting older people and encourage them to provide more useful services. SNS operators should encourage social support among older users and pay attention to sex differences and education differences. © 2018 AJA Inc.

Type Ia supernovae as standard candles

NASA Technical Reports Server (NTRS)

Branch, David; Miller, Douglas L.

1993-01-01

The distribution of absolute blue magnitudes among Type Ia supernovae (SNs Ia) is studied. Supernovae were used with well determined apparent magnitudes at maximum light and parent galaxies with relative distances determined by the Tully-Fisher or Dn - sigma techniques. The mean absolute blue magnitude is given and the observational dispersion is only sigma(MB) 0.36, comparable to the expected combined errors in distance, apparent magnitude, and extinction. The mean (B-V) color at maximum light is 0.03 +/- 0.04, with a dispersion sigma(B-V) = 0.20. The Cepheid-based distance to IC 4182, the parent galaxy of the normal and unextinguished Type Ia SN 1937C, leads to a Hubble constant of H(0) + 51 +/- 12 km/s Mpc. The existence of a few SNs Ia that appear to have been reddened and dimmed by dust in their parent galaxies does not seriously compromise the use of SNs Ia as distance indicators.

"Was it something I said?" "No, it was something you posted!" A study of the spiral of silence theory in social media contexts.

PubMed

Gearhart, Sherice; Zhang, Weiwu

2015-04-01

New media technologies make it necessary for scholars to reassess mass communication theories developed among legacy media. One such theory is the spiral of silence theory originally proposed by Noelle-Neumann in the 1970s. Increasing diversity of media content, selectivity, social networking site (SNS) interactivity, and the potential for anonymity have posed various challenges to its theoretical assumptions. While application of the spiral of silence in SNS contexts has been theorized, its empirical testing is scarce. To fill this void, the Pew 2012 Search, Social Networks, and Politics survey is used to test the theory. Results reveal that encountering agreeable political content predicts speaking out, while encountering disagreeable postings stifles opinion expression, supporting the spiral of silence theory in the SNS environment. However, certain uses of SNSs and psychological factors demonstrate a liberating effect on opinion expression.

Fast Monte Carlo simulation of a dispersive sample on the SEQUOIA spectrometer at the SNS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Granroth, Garrett E; Chen, Meili; Kohl, James Arthur

2007-01-01

Simulation of an inelastic scattering experiment, with a sample and a large pixilated detector, usually requires days of time because of finite processor speeds. We report simulations on an SNS (Spallation Neutron Source) instrument, SEQUOIA, that reduce the time to less than 2 hours by using parallelization and the resources of the TeraGrid. SEQUOIA is a fine resolution (∆E/Ei ~ 1%) chopper spectrometer under construction at the SNS. It utilizes incident energies from Ei = 20 meV to 2 eV and will have ~ 144,000 detector pixels covering 1.6 Sr of solid angle. The full spectrometer, including a 1-D dispersivemore » sample, has been simulated using the Monte Carlo package McStas. This paper summarizes the method of parallelization for and results from these simulations. In addition, limitations of and proposed improvements to current analysis software will be discussed.« less

State of the (net)work address Developing criteria for applying social networking to the work environment.

PubMed

Valdez, André Calero; Schaar, Anne Kathrin; Ziefle, Martina

2012-01-01

In an increasingly faster paced innovative world, maintaining the ability to innovate in spite of an aging work force will become every company's strongest leverage for success. Tapping the latent knowledge resources and creativity of overlooked employees and persisting crucial information for business conduct are promising results for social networking sites (SNS) in a working context. Usability and usefulness are exponential factors in creating a successful SNS. In order to make a SNS usable for a heterogeneous user group, analyses of user diversity in regard to social media need to be done. Furthermore differences in communication medium and frequency in regard to age, content, hierarchy position, departmental thresholds and company size need to be analyzed. For analysis purposes both qualitative and quantitative research methods were applied. Strong effects of age and communication content were found in survey with 194 participants.

Online Social Networking, Sexual Risk and Protective Behaviors: Considerations for Clinicians and Researchers.

PubMed

Holloway, Ian W; Dunlap, Shannon; Del Pino, Homero E; Hermanstyne, Keith; Pulsipher, Craig; Landovitz, Raphael J

2014-09-01

Online social networking refers to the use of internet-based technologies that facilitate connection and communication between users. These platforms may be accessed via computer or mobile device (e.g., tablet, smartphone); communication between users may include linking of profiles, posting of text, photo and video content, instant messaging and email. This review provides an overview of recent research on the relationship between online social networking and sexual risk and protective behaviors with a focus on use of social networking sites (SNS) among young people and populations at high risk for sexually transmitted infections (STIs). While findings are mixed, the widespread use of SNS for sexual communication and partner seeking presents opportunities for the delivery and evaluation of public health interventions. Results of SNS-based interventions to reduce sexual risk are synthesized in order to offer hands-on advice for clinicians and researchers interested in engaging patients and study participants via online social networking.

Effects of Perceived Values on Continuance Usage of Facebook

NASA Astrophysics Data System (ADS)

Yang, Heng-Li; Lai, Cheng-Yu

Facebook is one of the renowned social networking sites (SNS) on the Internet. As compared to the conventional SNS, it not only provides social interaction features, but has more entertainment elements on the website. Many Facebook users use the website for the purpose of playing the embedded games rather than use its original social features, i.e., individual's perceived values about the usage of Facebook may have changed. Consequently, it is an interesting issue to know individual's perceived values and satisfaction toward continuance usage of the new style SNS like Facebook. Based on prior literatures, three different value orientations, including social orientation, entertainment orientation and fashion orientation, were adopted in this study to examine their influence on individual's satisfaction and continuance intention to use Facebook. An empirical survey and partial least squares (PLS) technology was utilized to test the proposed hypotheses. Several empirical results were found. Both academic and practical implications are discussed.

Characteristics of Illinois School Districts That Employ School Nurses.

PubMed

Searing, Lisabeth M; Guenette, Molly

2016-08-01

Research indicates that school nursing services are cost-effective, but the National Association of School Nurses estimates that 25% of schools do not have a school nurse (SN). The purpose of this study was to identify the characteristics of Illinois school districts that employed SNs. This was a secondary data analysis of Illinois School Report Card system data as well as data obtained from district websites regarding SNs. Employment of an SN was determined for 95% of the 862 existing districts. Binary logistic regression analysis found that district size was the largest significant predictor of employment of an SN. Other factors included the type of district and diversity of the teaching staff as well as the percentage of students receiving special education services or with limited English proficiency. These findings indicate where to focus advocacy and policy efforts to encourage employment of SNs. © The Author(s) 2015.

Surface plasma source with saddle antenna radio frequency plasma generator.

PubMed

Dudnikov, V; Johnson, R P; Murray, S; Pennisi, T; Piller, C; Santana, M; Stockli, M; Welton, R

2012-02-01

A prototype RF H(-) surface plasma source (SPS) with saddle (SA) RF antenna is developed which will provide better power efficiency for high pulsed and average current, higher brightness with longer lifetime and higher reliability. Several versions of new plasma generators with small AlN discharge chambers and different antennas and magnetic field configurations were tested in the plasma source test stand. A prototype SA SPS was installed in the Spallation Neutron Source (SNS) ion source test stand with a larger, normal-sized SNS AlN chamber that achieved unanalyzed peak currents of up to 67 mA with an apparent efficiency up to 1.6 mA∕kW. Control experiments with H(-) beam produced by SNS SPS with internal and external antennas were conducted. A new version of the RF triggering plasma gun has been designed. A saddle antenna SPS with water cooling is fabricated for high duty factor testing.

Nurse-led epistaxis management within the emergency department.

PubMed

Hakim, Navid; Mummadi, Sangha Mitra; Jolly, Karan; Dawson, Julian; Darr, Adnan

2018-01-11

the incidence of epistaxis has increased secondary to increased life expectancy and morbidities. This study sought to assess the knowledge, practice and opinion relating to adequacy of training of advanced nurse practitioners (ANPs) and staff nurses (SNs) in the emergency department. a national survey was distributed over an 8-week period; this included a 3-point scoring system based on the National Institute for Health and Care Excellence Clinical Knowledge Summaries guidance on epistaxis management to assess overall performance. analysis included 109 ANPs and 101 SNs; 12% of ANPs achieved the maximum score, 40% scored 2, 25% scored 1, and 23% scored 0, while 14% of SNs achieved the maximum score, 24% scored 2, 29% scored 1, and 32% scored 0. Overall 88% of respondents advocated further training. significant deficits in knowledge regarding epistaxis management were highlighted. Further training could help to empower patients in basic first aid measures, subsequently reducing admissions rates.

[Sacral nerve stimulation in the treatment of the lower urinary tract function disorders].

PubMed

Miotła, Paweł; Kulik-Rechberger, Beata; Skorupski, Paweł; Rechberger, Tomasz

2011-11-01

Functional disorders of the female lower urinary tract like urge incontinence, idiopathic urinary retention and symptoms of urgency-frequency occasionally do not respond properly to classical behavioral and pharmacological therapy Therefore, additional alternative therapies are needed to alleviate these bothersome symptoms. Sacral neuromodulation (SNS) utilize mild electrical pulses which activate or suppress neural reflexes responsible for voiding by stimulating the sacral nerves that innervate the bladder, external urethral sphincter and pelvic floor muscles. The exact mechanism of SNS action is not yet fully understood but it is assumed that it influences the neuroaxis at different levels of the central nervous system and restores the balance between inhibitory and activatory control over the voiding reflex. There is numerous evidence on the success of SNS not only in the treatment of refractory urge incontinence in adult and children but also in idiopathic urinary retention and symptoms of urgency-frequency

A systematic review of clinical studies of electrical stimulation for treatment of lower urinary tract dysfunction.

PubMed

Monga, Ash K; Tracey, Michael R; Subbaroyan, Jeyakumar

2012-08-01

The aim of this manuscript was to provide a systematic literature review of clinical trial evidence for a range of electrical stimulation therapies in the treatment of lower urinary tract symptoms (LUTS). The databases MEDLINE, BIOSIS Previews, Inside Conferences, and EMBASE were searched. Original clinical studies with greater than 15 subjects were included. Seventy-three studies were included, representing implanted sacral nerve stimulation (SNS), percutaneous posterior tibial nerve stimulation (PTNS), and transcutaneous electrical stimulation (TENS) therapy modalities. Median mean reductions in incontinence episodes and voiding frequency were similar for implanted SNS and PTNS. However, long-term follow-up data to validate the sustained benefit of PTNS are lacking. Despite a substantial body of research devoted to SNS validation, it is not possible to definitively define the appropriate role of this therapy owing largely to study design flaws that inhibited rigorous intention to treat analyses for the majority of these studies.