Teaching PSS in business practice : A win-win-win approach

NARCIS (Netherlands)

Keskin, D.; Brezet, J.C.; Diehl, J.C.

2010-01-01

This paper presents the findings gained through the implementation of the renewed Product Service Systems (PSS) course within the Design for Sustainability curriculum in 2010. Based upon the outcomes of our recent PSS research projects in practice and evaluation of the earlier PSS courses a new

The Influence of Peer Groups on Academic Success

Science.gov (United States)

Sallee, Margaret W.; Tierney, William G.

2007-01-01

The authors examine how peer relationships influence students' academic success. After defining peer groups, the article considers the ways in which students' peer networks facilitate or inhibit access to academic resources. The authors argue that the composition and purpose of a peer group influences academic achievement and students' likelihood…

Spray-deposited PEDOT:PSS for inverted organic solar cells

Energy Technology Data Exchange (ETDEWEB)

Weickert, Jonas; Sun, Haiyan; Palumbiny, Claudia; Hesse, Holger Christian; Schmidt-Mende, Lukas [Ludwig-Maximilians-University Munich, Department of Physics and Center for NanoScience (CeNS), Amalienstr. 54, 80799 Munich (Germany)

2010-12-15

The method of spray-depositing PEDOT:PSS allows the fabrication of thin films with controlled thickness on polymer layers. PEDOT:PSS is used in inverted ITO/TiO{sub 2}/P3HT:PCBM/PEDOT:PSS/Ag solar cells to optimize the work function of the hole-collecting electrode. The interlayer is also found to protect the organic layer during metal top deposition and improve the contact between P3HT-PCBM and the Ag electrode, which is confirmed using two different metal-deposition techniques; thermal evaporation and sputtering. Cells with PEDOT:PSS show full V{sub OC} and efficiency immediately after fabrication, whereas devices without PEDOT:PSS exhibit low performance in the beginning and improve significantly during the first 10 days after production. Devices are long-term stable if stored in the dark and in ambient air and show no significant performance decrease after 80 days. No inert nitrogen atmosphere is needed for any fabrication step, thus reducing the potential production costs since no glove box has to be used. (author)

Estimation of the Influence of Power System Mathematical Model Parameter Uncertainty on PSS2A System Stabilizers

Directory of Open Access Journals (Sweden)

Adrian Nocoń

2015-09-01

Full Text Available This paper presents an analysis of the influence of uncertainty of power system mathematical model parameters on optimised parameters of PSS2A system stabilizers. Optimisation of power system stabilizer parameters was based on polyoptimisation (multi-criteria optimisation. Optimisation criteria were determined for disturbances occurring in a multi-machine power system, when taking into account transient waveforms associated with electromechanical swings (instantaneous power, angular speed and terminal voltage waveforms of generators. A genetic algorithm with floating-point encoding, tournament selection, mean crossover and perturbative mutations, modified for the needs of investigations, was used for optimisation. The impact of uncertainties on the quality of operation of power system stabilizers with optimised parameters has been evaluated using various deformation factors.

Autoclave Sterilization of PEDOT:PSS Electrophysiology Devices.

Science.gov (United States)

Uguz, Ilke; Ganji, Mehran; Hama, Adel; Tanaka, Atsunori; Inal, Sahika; Youssef, Ahmed; Owens, Roisin M; Quilichini, Pascale P; Ghestem, Antoine; Bernard, Christophe; Dayeh, Shadi A; Malliaras, George G

2016-12-01

Autoclaving, the most widely available sterilization method, is applied to poly(3,4-ethylenedioxythiophene) doped with polystyrene sulfonate (PEDOT:PSS) electrophysiology devices. The process does not harm morphology or electrical properties, while it effectively kills E. coli intentionally cultured on the devices. This finding paves the way to widespread introduction of PEDOT:PSS electrophysiology devices to the clinic. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Understanding the Capacitance of PEDOT:PSS

DEFF Research Database (Denmark)

Volkov, Anton V.; Wijeratne, Kosala; Mitraka, Evangelia

2017-01-01

Poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) is the most studied and explored mixed ion-electron conducting polymer system. PEDOT:PSS is commonly included as an electroactive conductor in various organic devices, e.g., supercapacitors, displays, transistors, and energy......-converters. In spite of its long-term use as a material for storage and transport of charges, the fundamentals of its bulk capacitance remain poorly understood. Generally, charge storage in supercapacitors is due to formation of electrical double layers or redox reactions, and it is widely accepted that PEDOT...

Surface analysis of the selective excimer laser patterning of a thin PEDOT:PSS film on flexible polymer films

Energy Technology Data Exchange (ETDEWEB)

Schaubroeck, David, E-mail: David.Schaubroeck@elis.ugent.be [Center for Microsystems Technology (CMST), imec and Ghent University, Technologiepark 15, B-9052 Ghent (Belgium); De Smet, Jelle; Willems, Wouter [Center for Microsystems Technology (CMST), imec and Ghent University, Technologiepark 15, B-9052 Ghent (Belgium); Cools, Pieter; De Geyter, Nathalie; Morent, Rino [Research Unit Plasma Technology (RUPT), Department of Applied Physics, Faculty of Engineering, Ghent University, Sint-Pietersnieuwstraat 41, B-9000 Ghent (Belgium); De Smet, Herbert; Van Steenbeerge, Geert [Center for Microsystems Technology (CMST), imec and Ghent University, Technologiepark 15, B-9052 Ghent (Belgium)

2016-07-15

Highlights: • Laser patterning of thin film PEDOT:PSS on polymer foils is characterized in great detail. • PEDOT:PSS does not need to be fully removed to create electrically insulating patterns. • The underlying polymer foil influences the ablation behavior. - Abstract: Fast patterning of highly conductive polymers like PEDOT:PSS (poly (3,4-ethylene dioxythiophene): polystyrene sulfonate) with lasers can contribute to the development of industrial production of liquid crystal displays on polymer foils. In this article, the selective UV laser patterning of a PEDOT:PSS film on flexible polymer films is investigated. Based on their optical properties, three polymer films are investigated: polyethylene terephthalate (PET), polymethyl methacrylate (PMMA) and cellulose triacetate (TAC). Ablation parameters for a 110 nm PEDOT:PSS film on these polymer films are optimized. A detailed study of the crater depth, topography and surface composition are provided using optical profilometry, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), respectively. The electrical insulation of the lines is measured and correlated to the crater analyses for different laser settings. Finally, potential ablation parameters for each of the polymer films are derived.

Energy level and thickness control on PEDOT:PSS layer for efficient planar heterojunction perovskite cells

Science.gov (United States)

Wang, Chunhua; Zhang, Chujun; Tong, Sichao; Xia, Huayan; Wang, Lijuan; Xie, Haipeng; Gao, Yongli; Yang, Junliang

2018-01-01

Efficient planar heterojunction perovskite solar cells (PHJ-PSCs) with an architecture of ITO/PEDOT:PSS/CH3NH3PbI3/PCBM/Al were fabricated by controlling the energy level and thickness of the PEDOT:PSS layer, where the PEDOT:PSS precursor was diluted with deionized water (H2O) and isopropyl alcohol (IPA), i.e. W-PEDOT:PSS and I-PEDOT:PSS. The performance parameters of the PHJ-PSCs showed soaring enhancement after employing W-PEDOT:PSS or I-PEDOT:PSS instead of pristine PEDOT:PSS (P-PEDOT:PSS), resulting in an increase of the power conversion efficiency (PCE) of W-PEDOT:PSS-based PHJ-PSCs to 15.60% from 11.95% for P-PEDOT:PSS-based PHJ-PSCs. The performance improvement results from two aspects. On the one hand, as compared to P-PEDOT:PSS, the occupied molecular orbital energy (HOMO) level of dilute PEDOT:PSS showed an impressive decrease and can well match the valence band of CH3NH3PbI3 film, resulting in less energy loss and a significant improvement in the open-circuit voltage (V oc). On the other hand, the dilute PEDOT:PSS could produce a thinner film as compared with the P-PEDOT:PSS, which also played an important role in the performance of the PHJ-PSCs. Furthermore, the electrochemical impedance spectroscopy (EIS) results indicated that the interface between perovskite and PEDOT:PSS was greatly improved by employing W-PEDOT:PSS or I-PEDOT:PSS, leading to an obvious decrease in the series resistance (R s) and an increase in the recombination resistance (R rec). The research demonstrated that diluting PEDOT:PSS with a common solvent, such as H2O and IPA, is a feasible low-temperature way of achieving efficient PHJ-PSCs.

Directives to support the design of changeable (I)PSS

NARCIS (Netherlands)

Pereira Pessoa, Marcus Vinicius; Jauregui Becker, Juan Manuel; Maier, Anja; Skec, Stanko; Kim, Harrison; Kokkolaras, Michael; Oehmen, Josef; Fadel, Georges; Salustri, Filippo; Van der Loos, Mike

2017-01-01

Product service models (PSM) benefits are not limited to its providers and costumers, but the whole society might also take advantage from its sustainability impact. Achieving these benefits, though, require changeable product service systems ((I)PSS). Changeability means the (I)PSS' modules have

Optical-Electrical-Chemical Engineering of PEDOT:PSS by Incorporation of Hydrophobic Nafion for Efficient and Stable Perovskite Solar Cells.

Science.gov (United States)

Ma, Shuang; Qiao, Wenyuan; Cheng, Tai; Zhang, Bing; Yao, Jianxi; Alsaedi, Ahmed; Hayat, Tasawar; Ding, Yong; Tan, Zhan'ao; Dai, Songyuan

2018-01-31

In PIN-type perovskite solar cells (PSCs), the hydroscopicity and acidity of the poly(3,4-ethylenedioxythiophene)-poly(styrene-sulfonate) (PEDOT:PSS) hole transport layer (HTL) have critical influences on the device stability. To eliminate these problems, Nafion, the hydrophobic perfluorosulfonic copolymer, is incorporated into PEDOT:PSS by a simple spin-coating process. For the modified film, Nafion/PSSH (poly(styrene sulfonate) acid) acts as an electron-blocking layer on the surface and the PEDOT-rich domain tends to gather into larger particles with better interchain charge transfer inside the film. Consequently, the modified PEDOT:PSS HTL shows enhanced conductivity and light transmittance as well as more favorable work function, ending up with the increased short-circuit current density (J sc ) and open-circuit voltage (V oc ) of the device. Finally, PSCs with Nafion-modified HTLs achieve the best power conversion efficiency of 16.72%, with 23.76% improvement compared with PEDOT:PSS-only devices (13.51%). Most importantly, the device stability is obviously enhanced because of the hydrophobicity and chemical and mechanical stability of the Nafion polymer that is enriched on the surface of the PEDOT:PSS film.

PEDOT:PSS-Containing Nanohydroxyapatite/Chitosan Conductive Bionanocomposite Scaffold: Fabrication and Evaluation

Directory of Open Access Journals (Sweden)

Alireza Lari

2016-01-01

Full Text Available Conductive poly(3,4-ethylenedioxythiophene-poly(4-styrene sulfonate (PEDOT:PSS was incorporated into nanohydroxyapatite/chitosan (nHA/CS composite scaffolds through a freezing and lyophilization technique. The bionanocomposite conductive scaffold was then characterized using several techniques. A scanning electron microscope image showed that the nHA and PEDOT:PSS were dispersed homogeneously in the chitosan matrix, which was also confirmed by energy-dispersive X-ray (EDX analysis. The conductive properties were measured using a digital multimeter. The weight loss and water-uptake properties of the bionanocomposite scaffolds were studied in vitro. An in vitro cell cytotoxicity test was carried out using mouse fibroblast (L929 cells cultured onto the scaffolds. Using a freezing and lyophilization technique, it was possible to fabricate three-dimensional, highly porous, and interconnected PEDOT:PSS/nHA/CS scaffolds with good handling properties. The porosity was 74% and the scaffold’s conductivity was 9.72±0.78 μS. The surface roughness was increased with the incorporation of nHA and PEDOT:PSS into the CS scaffold. The compressive mechanical properties increased significantly with the incorporation of nHA but did not change significantly with the incorporation of PEDOT:PSS. The PEDOT:PSS-containing nHA/CS scaffold exhibited significantly higher cell attachment. The PEDOT:PSS/nHA/CS scaffold could be a potential bionanocomposite conductive scaffold for tissue engineering.

A Study of Motivational Influences on Academic Achievement

Science.gov (United States)

Dishon-Berkovits, Miriam

2014-01-01

This study examined the influence of motivation on academic achievement. The theoretical rationale for the study is grounded in bridging two influential yet isolated literatures of motivation: goal setting theory and achievement goal theory. Although it is clear that academic performance should be influenced by assigned learning goals,…

Pseudospark switches (PSS) for pulsed power applications

Energy Technology Data Exchange (ETDEWEB)

Heine, F; Prucker, U; Frank, K; Goertler, A; Schwandner, A; Tkotz, R; Hoffmann, D H.H.; Christiansen, J [Univ. of Erlangen (Germany). Physics Dept. I

1997-12-31

Based on the pseudospark discharge, a low pressure gas discharge in a special geometry, fast closing switches for different pulsed power applications have been designed. Medium power PSS ({<=} 30 kA peak current) were used in laser circuits whereas high current PSS are tested successfully in high current pulsed power applications ({<=} 200 kA). For currents of a few kA the discharge is supported by cathode spots on the cold cathode surface. For higher currents, anode activity is observed too. Inserting semiconductor material seems not only to suppress high erosive spot formation but to support diffuse large-area electrode emission. A different approach to solving the problem of lowering the erosion rate is the multichannel PSS (MUPS). In order to distribute the discharge current to more than one single channel, three or more discharge channels are radial or coaxial arranged. With regard to high voltage applications the maximum hold-off voltage was increased by adding an intermediate electrode. (author). 1 figs., 12 refs.

Durability of PEDOT: PSS-pentacene Schottky diode

International Nuclear Information System (INIS)

Kang, K S; Lim, H K; Cho, K Y; Han, K J; Kim, Jaehwan

2008-01-01

The durability and failure cause of a polymer Schottky diode made with PEDOT : PSS-pentacene were investigated. A polymer Schottky diode was fabricated by dissolving pentacene in N-methylpyrrolidone (NMP) and mixing with PEDOT : PSS. Pentacene solution having a maximum concentration of approximately 9.7 mmoles was prepared by simply stirring the solution at room temperature for 36 h. As the pentacene concentration increased, the absorption of the broad UV regime increased dramatically. However, absorption peaks of pentacene at 301 and 260 nm were not observed for the PEDOT : PSS-pentacene. A three-layered polymer Schottky diode was fabricated and its current-voltage (I-V) characteristic was evaluated. The current was reduced by 7% in the first 50 min and then stabilized during biased electrical field sweeps. After 500 and 800 min, catastrophic failure occurred. FESEM images revealed that the electrode damage caused catastrophic failure of the Schottky diode. (fast track communication)

The Curious Out-of-Plane Conductivity of PEDOT : PSS

NARCIS (Netherlands)

van de Ruit, Kevin; Katsouras, Ilias; Bollen, Dirk; van Mol, Ton; Janssen, Rene A. J.; de Leeuw, Dago M.; Kemerink, Martijn

2013-01-01

For its application as transparent conductor in light-emitting diodes and photovoltaic cells, both the in-plane and out-of-plane conductivity of PEDOT:PSS are important. However, studies into the conductivity of PEDOT:PSS rarely address the out-of-plane conductivity and those that do, report widely

Improved stability of OLEDs with mild oxygen plasma treated PEDOT:PSS

International Nuclear Information System (INIS)

Zhou Yunfei; Yuan Yongbo; Cao Lingfang; Zhang Jie; Pang Hongqi; Lian Jiarong; Zhou Xiang

2007-01-01

We demonstrate improved stability of OLEDs with mild oxygen plasma-treated poly (3,4-ethylenedioxythiophene) doped with poly (styrenesulfonate) (PEDOT:PSS) as anode buffer layer. The devices with treated PEDOT:PSS layer exhibited dramatically enhanced lifetime by a factor of 9 compared to the control devices. We investigated the substantial changes in surface morphology of PEDOT:PSS layer after the mild oxygen plasma treatment by scanning electron microscopy and atomic force microscopy. We found that the appropriate treatment can form uniformly distributed nano scaled hillocks/islands on the surface of PEDOT:PSS layer, which possibly result in improved contact to hole transport layer and thus enhanced lifetime of the devices

Multiple congenital PSS in a dog: case report and literature review.

Science.gov (United States)

Leeman, Jessica J; Kim, Stanley E; Reese, David J; Risselada, Marije; Ellison, Gary W

2013-01-01

A 4 yr old spayed female mixed-breed dog presented with a 2 yr history of recurring increases in liver enzymes. Two congenital portosystemic shunts (PSSs) were identified using computed tomography (CT) angiography, which included a portoazygous and portorenal extrahepatic shunt. Double right renal veins were also identified. The shunts were successfully identified and attenuated with cellophane banding. Multiple congenital PSS is a rare phenomenon, but should be considered during exploratory laparotomy for PSS and in dogs with poor response to surgical attenuation of a single PSS. CT proved to be a crucial part of accurate diagnosis and surgical planning for this dog with multiple congenital PSS.

Framing design research for service orientation through PSS approaches

DEFF Research Database (Denmark)

Sakao, Tomohiko; Sandström, Gunilla Ölundh; Matzen, Detlef

2009-01-01

on the literature analysis, the authors present three crucial dimensions for service oriented design research, i.e. an offer dimension representing products and services, a provider dimension, and a customer/user dimension. In addition, three research targets are proposed; PSS-offer modelling, PSS development......, and PSS potential. Furthermore, several promising future research directions are identified. These include evaluating economic consequences or environmental benefits, establishing terminology, organizational issues, and developing methods and tools to support designers. The boundaries to other research...... fields are getting blurry and many aspects of other professionalisms must be taken into account. Thus, there is especially need in future research to open towards other research areas....

Low-Temperature Cross-Linking of PEDOT:PSS Films Using Divinylsulfone.

Science.gov (United States)

Mantione, Daniele; Del Agua, Isabel; Schaafsma, Wandert; ElMahmoudy, Mohammed; Uguz, Ilke; Sanchez-Sanchez, Ana; Sardon, Haritz; Castro, Begoña; Malliaras, George G; Mecerreyes, David

2017-05-31

Recent interest in bioelectronics has prompted the exploration of properties of conducting polymer films at the interface with biological milieus. Poly(3,4-ethylenedioxythiophene) doped with poly(styrenesulfonate) (PEDOT:PSS) from a commercially available source has been used as a model system for these studies. Different cross-linking schemes have been used to stabilize films of this material against delamination and redispersion, but the cost is a decrease in the electrical conductivity and/or additional heat treatment. Here we introduce divinylsulfone (DVS) as a new cross-linker for PEDOT:PSS. Thanks to the higher reactiveness of the vinyl groups of DVS, the cross-linking can be performed at room temperature. In addition, DVS does not reduce electronic conductivity of PEDOT:PSS but rather increases it by acting as a secondary dopant. Cell culture studies show that PEDOT:PSS:DVS films are cytocompatible and support neuroregeneration. As an example, we showed that this material improved the transconductance value and stability of an organic electrochemical transistor (OECT) device. These results open the way for the utilization of DVS as an effective cross-linker for PEDOT:PSS in bioelectronics applications.

Academic season does not influence cardiac surgical outcomes at US Academic Medical Centers.

Science.gov (United States)

Lapar, Damien J; Bhamidipati, Castigliano M; Mery, Carlos M; Stukenborg, George J; Lau, Christine L; Kron, Irving L; Ailawadi, Gorav

2011-06-01

Previous studies have demonstrated the influence of academic season on outcomes in select surgical populations. However, the influence of academic season has not been evaluated nationwide in cardiac surgery. We hypothesized that cardiac surgical outcomes were not significantly influenced by time of year at both cardiothoracic teaching hospitals and non-cardiothoracic teaching hospitals nationwide. From 2003 to 2007, a weighted 1,614,394 cardiac operations were evaluated using the Nationwide Inpatient Sample database. Patients undergoing cardiac operations at cardiothoracic teaching and non-cardiothoracic teaching hospitals were identified using the Association of American Medical College's Graduate Medical Education Tracking System. Hierarchic multivariable logistic regression analyses were used to estimate the effect of academic quarter on risk-adjusted outcomes. Mean patient age was 65.9 ± 10.9 years. Women accounted for 32.8% of patients. Isolated coronary artery bypass grafting was the most common operation performed (64.7%), followed by isolated valve replacement (19.3%). The overall incidence of operative mortality and composite postoperative complication rate were 2.9% and 27.9%, respectively. After accounting for potentially confounding risk factors, timing of operation by academic quarter did not independently increase risk-adjusted mortality (p = 0.12) or morbidity (p = 0.24) at academic medical centers. Risk-adjusted mortality and morbidity for cardiac operations were not associated with time of year in the US at teaching and nonteaching hospitals. Patients should be reassured of the safety of performance of cardiac operations at academic medical centers throughout a given academic year. Copyright © 2011 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Step-by-step towards PSS – Evaluating, Deciding and Executing

DEFF Research Database (Denmark)

Neugebauer, Line Maria; Mougaard, Krestine; McAloone, Tim C.

2012-01-01

Successful implementation of product-service system (PSS) as business strategy has proven lucrative through many industry examples. However, companies should tread carefully before committing to a costly restructuring towards PSS business creation. This paper claims that before a company moves fr...

Industry specific PSS: A study of opportunities and barriers for maritime suppliers

DEFF Research Database (Denmark)

Andersen, Jakob Axel Bejbro; McAloone, Tim C.; Garcia i Mateu, Adrià

2013-01-01

Product-Service System (PSS) business models are finding applications with suppliers and manufacturers across industries, but the models have yet to establish a strong foothold in the maritime sector. A number of metrics for evaluating the attractiveness of PSS business models have been proposed...... in chiefly design research and operations management literature. This paper applies a number of these metrics to the maritime sector using data from a number of maritime suppliers. It is found that the industry is, at least in some aspects, attractive from this PSS metrics standpoint. To explain the inherent...... lack of PSS maturity in the industry despite this metrics-based conclusion, the discussion moves beyond the quantitative factors and considers a number of organisational, structural and cultural issues that stand in the way of PSS. This paper is based on the initial responses provided by maritime...

Environmentally Friendly Plasma-Treated PEDOT:PSS as Electrodes for ITO-Free Perovskite Solar Cells.

Science.gov (United States)

Vaagensmith, Bjorn; Reza, Khan Mamun; Hasan, Md Nazmul; Elbohy, Hytham; Adhikari, Nirmal; Dubey, Ashish; Kantack, Nick; Gaml, Eman; Qiao, Qiquan

2017-10-18

Solution processed poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) transparent electrodes (TEs) offer great potential as a low cost alternative to expensive indium tin oxide (ITO). However, strong acids are typically used for enhancing the conductivity of PEDOT:PSS TEs, which produce processing complexity and environmental issues. This work presents an environmentally friendly acid free approach to enhance the conductivity of PEDOT:PSS using a light oxygen plasma treatment, in addition to solvent blend additives and post treatments. The plasma treatment was found to significantly reduce the sheet resistance of PEDOT:PSS TEs from 85 to as low as 15 Ω sq -1 , which translates to the highest reported conductivity of 5012 S/cm for PEDOT:PSS TEs. The plasma treated PEDOT:PSS TE resulted in an ITO-free perovskite solar cell efficiency of 10.5%, which is the highest reported efficiency for ITO-free perovskite solar cells with a PEDOT:PSS electrode that excludes the use of acid treatments. This research presents the first demonstration of this technology. Moreover, the PEDOT:PSS TEs enabled better charge extraction from the perovskite solar cells and reduced hysteresis in the current density-voltage (J-V) curves.

Product/Service-System Origins and Trajectories: A Systematic Literature Review of PSS Definitions and their Characteristics

DEFF Research Database (Denmark)

Haase, Ronja P.; Pigosso, Daniela Cristina Antelmi; McAloone, Tim C.

2017-01-01

Literature provides multiple definitions on Product/Service-Systems (PSS), and as the field develops, certain trajectories emerge. The purpose ofthis article is to provide an overview of the stabilization of PSS definitions within PSS research, by presenting the most prominent PSS definitionsand...... their interrelationships. As the result of a strict protocol, the paper identifies 52 prominent definitions related to PSS, where the citationrelations between the prominent definitions are studied and graphically illustrated. The definitions are furthermore analyzed to identify commonPSS definition characteristics...... and eleven different characteristics identified. Descriptive analysis is carried out on the identified PSS definitioncharacteristics, to determine commonalties and differences in the field. Even though the literature provides many different variations of PSS definitions, there is certain convergence...

Total dynamic response of a PSS vehicle negotiating asymmetric road excitations

Science.gov (United States)

Zhu, Jian Jun; Khajepour, Amir; Esmailzadeh, Ebrahim

2012-12-01

A planar suspension system (PSS) is a novel automobile suspension system in which an individual spring-damper strut is implemented in both the vertical and longitudinal directions, respectively. The wheels in a vehicle with such a suspension system can move back and forth relative to the chassis. When a PSS vehicle experiences asymmetric road excitations, the relative longitudinal motion of wheels with respect to the chassis in two sides of the same axle are not identical, and thus the two wheels at one axle will not be aligned in the same axis. The total dynamic responses, including those of the bounce, pitch and the roll of the PSS vehicle, to the asymmetric road excitation may exhibit different characteristics from those of a conventional vehicle. This paper presents an investigation into the comprehensive dynamic behaviour of a vehicle with the PSS, in such a road condition, on both the straight and curved roads. The study was carried out using an 18 DOF full-car model incorporating a radial-spring tyre-ground contact model and a 2D tyre-ground dynamic friction model. Results demonstrate that the total dynamic behaviour of a PSS vehicle is generally comparable with that of the conventional vehicle, while PSS exhibits significant improvement in absorbing the impact forces along the longitudinal direction when compared to the conventional suspension system. The PSS vehicle is found to be more stable than the conventional vehicle in terms of the directional performance against the disturbance of the road potholes on a straight line manoeuvre, while exhibiting a very similar handling performance on a curved line.

Nanostructural optimization of silicon/PEDOT:PSS hybrid solar cells for performance improvement

International Nuclear Information System (INIS)

Wang, Yanzhou; Shao, Pengfei; Li, Yali; Li, Junshuai; He, Deyan; Chen, Qiang

2017-01-01

In this paper, an inverted silicon (Si) nanopyramid (iSiNP) surface structure with low aspect ratio and remarkable antireflection is developed through sequential treatments of NaOH and HF/CH 3 COOH/HNO 3 solutions to Si nanowire (SiNW)-textured Si wafers, which are prepared by traditional electroless chemical etching. The iSiNP/PEDOT:PSS hybrid solar cell is fabricated through conformally spin-coating poly(3.4-ethylene dioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) onto the iSiNPs; it exhibits enhanced device performance owing to the improved junction and contact quality as compared to the SiNW/PEDOT:PSS counterpart. A power conversion efficiency (PCE) of 9.6% mainly contributed from an increased fill factor (FF) of 0.61 and improved open circuit voltage ( V oc ) of 0.53 V is delivered by the iSiNP/PEDOT:PSS solar cell. As a comparison, the SiNW/PEDOT:PSS structure delivers a 7.1% PCE with a FF of 0.45 and V oc of 0.46 V. Considering the submicro-scale characteristic dimensions, iSiNPs are expected to be applicable to highly efficient thin film Si/PEDOT:PSS hybrid solar cells. (paper)

Reflections on product/service-system (PSS) conceptualisation in a course setting

DEFF Research Database (Denmark)

Tan, Adrian; McAloone, Timothy Charles; Lauridsen, Erik Hagelskjær

2009-01-01

Product/service-system (PSS) approaches have over the past decade received considerable attention as possible sustainable innovation strategies. This paper presents and reflects upon the background, rationale and experiences behind a PSS design methodology applied with engineering students...... in a project course for the past five years. The methodology proposes four complementary dimensions of PSS: value proposition, product life cycle, activity modelling cycle and actor network, that all seem to comprehensively describe the essential conceptual design perspectives. Each of these dimensions...

Renal diagnostic nuclear medicine procedures in progressive systemic scleroderma (PSS)

Energy Technology Data Exchange (ETDEWEB)

Ammari, B.; Hotze, A.; Gruenwald, F.; Biersack, H.J.; Blitz, H.; Kuester, W.; Kreysel, H.W.

1989-02-01

The involvement of kidneys in progressive systemic scleroderma (PSS) is one of the most frequent causes of death in this disease. Using clinical criteria and laboratory tests only the frequency of kidney involvement would be clearly underestimated. Invasive diagnostic procedures such as biopsy and angiography can not be applied in those patients. Nuclear medicine techniques (hippurate clearance, DMSA-scan), however, offer non invasive and sensitive methods in the diagnosis of renal involvement in PSS patients. In our study 46 of 76 patients (60%) revealed pathologic findings. The mentioned diagnostic techniques show a high sensitivity and are in agreement with pathological findings described in PSS.

Renal diagnostic nuclear medicine procedures in progressive systemic scleroderma (PSS)

International Nuclear Information System (INIS)

Ammari, B.; Hotze, A.; Gruenwald, F.; Biersack, H.J.; Blitz, H.; Kuester, W.; Kreysel, H.W.

1989-01-01

The involvement of kidneys in progressive systemic scleroderma (PSS) is one of the most frequent causes of death in this disease. Using clinical criteria and laboratory tests only the frequency of kidney involvement would be clearly underestimated. Invasive diagnostic procedures such as biopsy and angiography can not be applied in those patients. Nuclear medicine techniques (hippurate clearance, DMSA-scan), however, offer non invasive and sensitive methods in the diagnosis of renal involvement in PSS patients. In our study 46 of 76 patients (60%) revealed pathologic findings. The mentioned diagnostic techniques show a high sensitivity and are in agreement with pathological findings described in PSS. (orig.) [de

LOFT facility PSS experiments: analysis of wet well vertical loads resulting from transient initiation

International Nuclear Information System (INIS)

Berta, V.T.

1977-05-01

Fourteen experiments on the Loss-of-Fluid Test (LOFT) facility pressure suppression system (PSS) are analyzed in relation to the vertical load generated on the suppression tank in the first 0.5 sec of the transient. Variations in principle parameters affecting the generation of vertical loads were included in the experiments. The internal and external vent submergences are identified from the analysis as being parameters which are first order in influencing the magnitude of the vertical load. These parameters are geometric in nature and depend only on PSS design. Physical parameters of total energy input and rate of energy input to the dry well, which influence the dry well pressurization, also are identified as being first order in influencing the magnitude of the vertical loads. The vertical load magnitude is a direct function of these geometric and physical parameters. The analysis indicates that a small value in any one of the parameters will cause the vertical load to be small and to have little dependence on the magnitude of the other parameters. In addition, the phenomena of nonuniform nonsynchronized vent inlet pressures, which have origins that are either geometric, physical, or a combination of both, act as a significant vertical load reduction mechanism

Pseudo-spark switch (PSS) characteristics under different operation conditions

Energy Technology Data Exchange (ETDEWEB)

Hamad, B. H., E-mail: dr.bassmahussain@gmail.com; Ahmad, A. K., E-mail: ahmad.kamal@sc.nahrainuniv.edu.iq [College of Science, Al Nahrain University, Jadria, Baghdad (Iraq); Lateef, K. H., E-mail: kamalhlatif@yahoo.com [Ministry of Science and Technology, Jadria, Baghdad (Iraq)

2016-08-15

The present paper concentrates on the characteristics of the pseudospark switch (PSS) designed in a previous work. The special characteristics of PSS make it a replacement for other high voltage switches such as thyratrons and ordinary high-pressure spark gaps. PSS is characterized by short rise time and small jitter time. The pseudo park chamber consists of two hollow cylindrical electrodes made of a stainless steel material (type 306L) separated by an insulator. The insulator used in our design is a glazed ceramic 70 mm in diameter and 3.5 mm in thickness. A PSS with an anode voltage of 29.2 kV, and a current of 3.6 kA and 11 ns rise time was achieved and used successfully at a repetition rate of about 2.2 kHz. A simple trigger circuit designed, built, and used effectively reaching more than 1.56 kV trigger pulse which is sufficient to ignite the argon gas inside the cathode to cause a breakdown. A non-inductive dummy load is designed to be a new technique to find the accurate value of the PSS inductance. A jitter time of ±10 ns pulses is observed to occur in a reliable manner for more than 6 h of continuous operation. In this research, the important parameters of this switch like rise time, peak current, and anode voltage were studied at various values of charging capacitance. The lifetime of this system is depending on the kind of the electrode material and on the type of insulation material in the main gap of the pseudospark switch.

Emotional intelligence, perceived stress and academic performance of Sri Lankan medical undergraduates

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P. Ranasinghe

2017-02-01

Full Text Available Abstract Background Previous research has shown that higher Emotional Intelligence (EI is associated with better academic and work performance. The present study intended to explore the relationship between EI, perceived stress and academic performance and associated factors among medical undergraduates. Methods This descriptive cross-sectional research study was conducted among 471 medical undergraduates of 2nd, 4th and final years of University of Colombo, Sri Lanka. Students were rated on self administered Perceived Stress Scale (PSS and Schutte Self-Report Emotional Intelligence Test (SEIT. Examination results were used as the dichotomous outcome variable in a logistic regression analysis. Results Females had higher mean EI scores (p = 0.014. A positive correlation was found between the EI score and the number of extracurricular activities (r = 0.121, p = 0.008. Those who were satisfied regarding their choice to study medicine, and who were planning to do postgraduate studies had significantly higher EI scores and lower PSS scores (p <0.001. Among final year undergraduates, those who passed the Clinical Sciences examination in the first attempt had a higher EI score (p <0.001 and a lower PSS score (p <0.05. Results of the binary logistic-regression analysis in the entire study population indicated that female gender (OR:1.98 and being satisfied regarding their choice of the medical undergraduate programme (OR:3.69 were significantly associated with passing the examinations. However, PSS Score and engagement in extracurricular activities were not associated with ‘Examination Results’. Conclusions Higher EI was associated with better academic performance amongst final year medical students. In addition a higher EI was observed in those who had a higher level of self satisfaction. Self-perceived stress was lower in those with a higher EI. Enhancing EI might help to improve academic performance among final year medical

Emotional intelligence, perceived stress and academic performance of Sri Lankan medical undergraduates.

Science.gov (United States)

Ranasinghe, P; Wathurapatha, W S; Mathangasinghe, Y; Ponnamperuma, G

2017-02-20

Previous research has shown that higher Emotional Intelligence (EI) is associated with better academic and work performance. The present study intended to explore the relationship between EI, perceived stress and academic performance and associated factors among medical undergraduates. This descriptive cross-sectional research study was conducted among 471 medical undergraduates of 2nd, 4th and final years of University of Colombo, Sri Lanka. Students were rated on self administered Perceived Stress Scale (PSS) and Schutte Self-Report Emotional Intelligence Test (SEIT). Examination results were used as the dichotomous outcome variable in a logistic regression analysis. Females had higher mean EI scores (p = 0.014). A positive correlation was found between the EI score and the number of extracurricular activities (r = 0.121, p = 0.008). Those who were satisfied regarding their choice to study medicine, and who were planning to do postgraduate studies had significantly higher EI scores and lower PSS scores (p <0.001). Among final year undergraduates, those who passed the Clinical Sciences examination in the first attempt had a higher EI score (p <0.001) and a lower PSS score (p <0.05). Results of the binary logistic-regression analysis in the entire study population indicated that female gender (OR:1.98) and being satisfied regarding their choice of the medical undergraduate programme (OR:3.69) were significantly associated with passing the examinations. However, PSS Score and engagement in extracurricular activities were not associated with 'Examination Results'. Higher EI was associated with better academic performance amongst final year medical students. In addition a higher EI was observed in those who had a higher level of self satisfaction. Self-perceived stress was lower in those with a higher EI. Enhancing EI might help to improve academic performance among final year medical student and also help to reduce the stress levels and cultivate

Enhanced thermoelectric properties of PEDOT/PSS/Te composite films treated with H2SO4

International Nuclear Information System (INIS)

Song, Haijun; Cai, Kefeng; Shen, Shirley

2016-01-01

Firstly, tellurium (Te) nanorods with a high Seebeck coefficient have been integrated into a conducting polymer PEDOT/PSS to form PEDOT/PSS/Te composite films. The Seebeck coefficient of the PEDOT/PSS/Te (90 wt.%) composite films is ~191 μV/K, which is about 13 times greater than that of pristine PEDOT/PSS. Then, H 2 SO 4 treatment has been used to further tune the thermoelectric properties of the composite films by adjusting the doping level and increasing the carrier concentration. After the acid treatment, the electrical conductivity of the composite films has increased from 0.22 to 1613 S/cm due to the removal of insulating PSS and the structural rearrangement of PEDOT. An optimized power factor of 42.1 μW/mK 2 has been obtained at room temperature for a PEDOT/PSS/Te (80 wt.%) sample, which is about ten times larger than that of the untreated PEDOT/PSS/Te composite film.

How to Distinguish Patients with pSS among Individuals with Dryness without Invasive Diagnostic Studies

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Agata Sebastian

2018-01-01

Full Text Available In the course of pSS, inflammatory cell infiltration consists mainly of lymphocytes infiltrating exocrine glands, which leads to their impaired function. The characteristic feature is generalized dryness. The aim of this study was to attempt to answer the question whether it is possible to distinguish between patients with pSS and individuals with dryness caused by other pathologies without applying invasive studies. The study included 68 patients with pSS and 43 healthy controls with dryness. FS ≥ 1 was observed in 90% of patients with pSS (with or without dryness, and only in 23% of the control group (only with xerostomia. In the pSS group, anaemia (p=0.0085, lymphocytopenia (p=0.0006, elevated ERS (p=0.001, higher RF titer, and ANA antibodies were noted. Configuration of anti-SSA + SSB + Ro52 antibodies was characteristic for the pSS group. Considering the clinical symptoms, statistically significant differences were noted between pSS patients and the control group in frequency (p=0.02 and severity (p=0.042 of fatigue, lymphadenopathy, major salivary gland involvement, and photosensitivity to UV light. In conclusion, invasive methods are pivotal in pSS diagnosis in this salivary gland biopsy. Chronic fatigue syndrome is more common in pSS patients and can be subjective distinguishing factor in the group of people with dryness.

Business-IT alignment in PSS value networks : a capability-based framework

NARCIS (Netherlands)

Bagheri, S.; Kusters, R.J.; Trienekens, J.J.M.; Camarinha-Matos, L.M.; Afsarmanesh, H.

2014-01-01

Advanced information technology (IT) is regarded as a foundation for the operation of product-service system (PSS) value networks. This requires alignment between IT and PSS business strategy. Business‐IT alignment (BIA) in a value network can raise the ability of partners to collaborate effectively

CNNH_PSS: protein 8-class secondary structure prediction by convolutional neural network with highway.

Science.gov (United States)

Zhou, Jiyun; Wang, Hongpeng; Zhao, Zhishan; Xu, Ruifeng; Lu, Qin

2018-05-08

Protein secondary structure is the three dimensional form of local segments of proteins and its prediction is an important problem in protein tertiary structure prediction. Developing computational approaches for protein secondary structure prediction is becoming increasingly urgent. We present a novel deep learning based model, referred to as CNNH_PSS, by using multi-scale CNN with highway. In CNNH_PSS, any two neighbor convolutional layers have a highway to deliver information from current layer to the output of the next one to keep local contexts. As lower layers extract local context while higher layers extract long-range interdependencies, the highways between neighbor layers allow CNNH_PSS to have ability to extract both local contexts and long-range interdependencies. We evaluate CNNH_PSS on two commonly used datasets: CB6133 and CB513. CNNH_PSS outperforms the multi-scale CNN without highway by at least 0.010 Q8 accuracy and also performs better than CNF, DeepCNF and SSpro8, which cannot extract long-range interdependencies, by at least 0.020 Q8 accuracy, demonstrating that both local contexts and long-range interdependencies are indeed useful for prediction. Furthermore, CNNH_PSS also performs better than GSM and DCRNN which need extra complex model to extract long-range interdependencies. It demonstrates that CNNH_PSS not only cost less computer resource, but also achieves better predicting performance. CNNH_PSS have ability to extracts both local contexts and long-range interdependencies by combing multi-scale CNN and highway network. The evaluations on common datasets and comparisons with state-of-the-art methods indicate that CNNH_PSS is an useful and efficient tool for protein secondary structure prediction.

Development of an Innovation Model Based on a Service-Oriented Product Service System (PSS

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Seungkyum Kim

2015-10-01

Full Text Available Recently, there have been many attempts to cope with increasingly-diversified and ever-changing customer needs by combining products and services that are critical components of innovation models. Although not only manufacturers, but also service providers, try to integrate products and services, most of the previous studies on Product Service System (PSS development deal with how to effectively integrate services into products from the product-centric point of view. Services provided by manufacturers’ PSSes, such as delivery services, training services, disposal services, and so on, offer customers ancillary value, whereas products of service providers’ PSSes enrich core value by enhancing the functionality and quality of the service. Thus, designing an effective PSS development process from the service-centric point of view is an important research topic. Accordingly, the purpose of this paper is to propose a service-oriented PSS development process, which consists of four stages: (1 strategic planning; (2 idea generation and selection; (3 service design; and (4 product development. In the proposed approach, the PSS development project is initiated and led by a service provider from a service-centric point of view. From the perspective of methodology, customer needs are converted into product functions according to Quality Function Deployment (QFD, while Analytic Hierarchy Process (AHP is employed to prioritize the functions. Additionally, this paper illustrates a service-oriented PSS development that demonstrates the application of the proposed process. The proposed process and illustration are expected to serve as a foundation for research on service-oriented PSS development and as a useful guideline for service providers who are considering the development of a service-oriented PSS.

Avidin/PSS membrane microcapsules with biotin-binding activity.

Science.gov (United States)

Endo, Yoshihiro; Sato, Katsuhiko; Sugimoto, Kentaro; Anzai, Jun-ichi

2011-08-15

Polyelectrolyte microcapsules with avidin-poly(styrene sulfonate) (PSS) membrane were prepared by a layer-by-layer deposition technique. The uptake and release of biotin-labeled fluorescein (b-FITC) as well as immobilization of biotin-labeled glucose oxidase (b-GOx) to the microcapsule were studied. The polyelectrolyte microcapsules were prepared by coating the surface of calcium carbonate (CaCO(3)) microparticles with an avidin/PSS multilayer membrane, followed by dissolution of CaCO(3) core in an ethylenediaminetetraacetic acid solution. Inner and outer poly(allylamine)/PSS films were required to isolate the microcapsules, whereas microcapsules could not be formed without the support. The uptake of b-FITC into the microcapsule was highly enhanced through a strong binding of b-FITC to avidin as compared with the uptake of biotin-free FITC. Release of b-FITC from the microcapsule was accelerated upon addition of biotin due to a competitive binding of the added biotin to the binding site of avidin. Similarly, the surface of microcapsule was modified with b-GOx with retaining its catalytic activity. Copyright © 2011 Elsevier Inc. All rights reserved.

Caracterização de hidrogéis condutores constituídos por PAAm e PEDOT/PSS por meio de planejamento fatorial Characterization of conducting hydrogels made with PAAm and PEDOT/PSS using factorial design

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Fauze A. Aouada

2008-06-01

, maximum compression stress, ionic conductance and relative intensity of light transmitted through the hydrogel. ANOVA was obtained using Statistical Software®. The results of the twelve runs from the factorial design (eight runs from 2³ plus four central point replicates were applied to evaluate the main effects and their interaction, in addition to decide if they are statistically significant. The results demonstrated that mechanical stability of semi-IPN hydrogels is preserved, with PEDOT/PSS creating additional entanglements within the PAAm network. In addition, the optical properties are strongly influenced by the presence of PEDOT/PSS. In summary, hydrogels could be synthesized with controlled hydrophilicity, transparency and mechanical stability, which is important for optical devices.

Effect of Secondary Doping Using Sorbitol on Structure and Transport Properties of PEDOT-PSS Thin Films

Science.gov (United States)

Khasim, Syed; Pasha, Apsar; Roy, Aashish S.; Parveen, Ameena; Badi, Nacer

2017-07-01

Poly(3,4-ethylene dioxythiophene):poly(styrenesulphonate) (PEDOT-PSS) in the recent past has emerged as one of the most fascinating conducting polymers for many device applications. The unique feature of PEDOT-PSS is its transparency in the entire visible spectrum with excellent thermal stability. The PEDOT-PSS as prepared as an aqueous dispersion has very low conductivity, and it hinders the performance of a device. In this work we report the conductivity enhancement of PEDOT-PSS thin films through secondary doping using a polar organic solvent such as sorbitol. The mechanism of conductivity enhancement was studied through various physical and chemical characterizations. The effect of sorbitol concentration on structure and transport properties of PEDOT-PSS thin films was investigated in detail. The structural and morphological modifications in PEDOT-PSS due to the addition of sorbitol was studied through Fourier transform spectroscopy, Ultra Violet-visible spectroscopy, theromogravimetric analysis, scanning electron microscopy and atomic force microscopy. The interactions resulting from conformational changes of PEDOT chains that changes from coiled to linear structure due to the sorbitol treatment significantly improves the conductivity of PEDOT-PSS films. The secondary doping of sorbitol reduces the energy barrier that facilitates the charge carrier hopping leading to enhanced conductivity. We have observed that the conductivity of PEDOT-PSS thin films was increased by two fold due to sorbitol treatment when compared to conductivity of pure PEDOT-PSS. We have carried out detailed analysis of dielectric parameters of sorbitol-treated PEDOT-PSS films and found that sorbitol treatment has a significant effect on various dielectric attributes of PEDOT-PSS films. Hence, secondary doping using sorbitol could be a useful way to effectively tailor the conductivity and dielectric properties of PEDOT-PSS thin films that can be used as flexible electrodes in

Assessing health-related quality of life in primary Sjögren's syndrome-The PSS-QoL.

Science.gov (United States)

Lackner, Angelika; Stradner, Martin H; Hermann, Josef; Unger, Julia; Stamm, Tanja; Graninger, Winfried B; Dejaco, Christian

2017-11-27

To develop a questionnaire for the assessment of health-related quality of life (HRQL) in primary Sjögren's syndrome (PSS), and to test its psychometric properties. Based on the concepts of a previous qualitative study, a questionnaire for the assessment of HRQL in PSS (PSS-QoL) was developed. Psychometric testing of PSS-QoL was performed after revising the first draft with feedback of patients (n = 6) and clinicians (n = 4). Convergent construct validity was assessed by correlating the score with the EULAR Sjögren's Syndrome Patient Reported Index (ESSPRI), EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI) and Euro-QoL 5D (EQ-5D). Reliability was examined by asking patients to complete the questionnaire twice 1-2 weeks apart. An English Version of the PSS-QoL was developed by using standard methodology with forward and back translation. Out of the 75 PSS patients, 91% were female, mean (±SD) age was 58.5 ± 12.5 years. PSS-QoL consists of 25 questions and can be divided into two main categories: physical (discomfort and dryness) and psychosocial. The internal consistency of the PSS-QoL revealed a Crohnbach's α of 0.892. Strong and moderate correlations were found between the PSS-QoL and ESSPRI (corr coeff = 0.755) and EQ. 5D-pain/discomfort (corr coeff = 0.531). Reproducibility of the PSS-QoL was high, yielding an ICC of 0.958 (95% CI: 0.926-0.981). The PSS-QoL is the first specific tool for the assessment of patients' HRQL in PSS and showed good psychometric properties. It may serve as a novel patient-reported outcome measure in future clinical studies. Copyright © 2017 Elsevier Inc. All rights reserved.

Influence of academic procrastination and personality types on ...

African Journals Online (AJOL)

The study examined the influence of academic procrastination and personality types on the academic achievement and efficacy of In-school adolescents in Ibadan, Oyo state. Two hundred participants were randomly selected from four schools in Akinyele Local Government area of Oyo state. Multiple regression analysis ...

Effect of incorporation of silver nanoparticles in PEDOT:PSS layer on performance of organic solar cell

Science.gov (United States)

Singh, Joginder; Nirwal, Varun Singh; Bhatnagar, P. K.; Peta, Koteswara Rao

2018-05-01

Solution processable organic solar cells have attracted significant interest in scientific community due to their easy processability, flexibility and eco friendly fabrication. In these organic solar cells structure, PEDOT:PSS layer has major importance as it used as hole transporting layer. In the present work, we have analyzed the effect of incorporation of silver nanoparticles (AgNPs) in PEDOT:PSS layer for P3HT:PCBM based organic solar cells. The presence of Ag nanoparticles in PEDOT:PSS film is confirmed by atomic force microscopy (AFM) images. It has been observed that PEDOT:PSS layer with AgNPs has ˜5.4% more transmittance than PEDOT:PSS layer in most of the visible region, which helps in reaching more light on active layer. Finally, solar cell with structure ITO/PEDOT:PSS:AgNPs/Al is fabricated and J-V characteristics are plotted under illumination. It is observed that there is a significant (˜10%) enhancement in short circuit current and slight increment in open circuit voltage with addition of AgNPs in PEDOT:PSS layer. The calculated value of power conversion efficiency (PCE) of fabricated device without AgNPs in PEDOT:PSS was 1.67%, which increased to 2.02% after addition of AgNPs in PEDOT:PSS layer.

Timing and Targeting of PSS Methods and Tools: An Empirical Study amongst Academic Contributors

DEFF Research Database (Denmark)

Nøhr Hinz, Hector; Bey, Niki; McAloone, Tim C.

2013-01-01

The emergence of product/service-systems has meant that development methods for such systems have emerged from academia. This paper investigates existing methods that are aimed at developing product/service-systems. Two aspects are determined for each examined method. The first aspect that has been...... surveyed is when a given method is meant to be used in the development of a product/service-system. This aspect has been determined through a qualitative assessment of each method. The second aspect surveyed is which persons in an organisation who are seen as the main drivers in the use of the methods....... To gain this insight a questionnaire for each method has been conducted with the authors of the methods as participants. The main finding indicates that current PSS methods cannot thoroughly support the development of product/ service-systems as their specificity is too low and that the methods need...

Assessing product service systems (PSS)

DEFF Research Database (Denmark)

Hsuan, Juliana; McAloone, Tim C.; Neugebauer, Line

We apply a management tool to classify different integrated PSS within the context of Danish maritime industry. We investigate how a firm should organize its operations to manage the transition from being a manufacturing to a servitizing company, and to provide a guideline for strategic positioni...... and planning of the balance between product sales and service activities....

The Influence of an Academic Pharmacy Mentorship Program on Mentees’ Commitment to Pursue an Academic Career

Science.gov (United States)

Sierra, Caroline M.

2017-01-01

The objective of this study was to determine the influence of the American Association of Colleges of Pharmacy (AACP) Walmart Scholars Program on mentees’ attitudes towards and decision to pursue a career in academia. Upon completion of the AACP Walmart* Scholars Program, wherein mentor-mentee pairs attend the AACP Annual Meeting to learn about academic pharmacy careers, mentees wrote essays evaluating the program. Their views on academic pharmacy careers were analyzed for themes in the evaluations. Of the mentees who addressed the impact of the program on their perspectives on a career in academic pharmacy, over half stated the program positively influenced pursuit of such a career. This reinforces the importance of mentorship for those interested in or new to academic pharmacy. PMID:28289293

The Influence of an Academic Pharmacy Mentorship Program on Mentees' Commitment to Pursue an Academic Career.

Science.gov (United States)

Sierra, Caroline M; Adams, Jennifer

2017-02-25

The objective of this study was to determine the influence of the American Association of Colleges of Pharmacy (AACP) Walmart Scholars Program on mentees' attitudes towards and decision to pursue a career in academia. Upon completion of the AACP Walmart Scholars Program, wherein mentor-mentee pairs attend the AACP Annual Meeting to learn about academic pharmacy careers, mentees wrote essays evaluating the program. Their views on academic pharmacy careers were analyzed for themes in the evaluations. Of the mentees who addressed the impact of the program on their perspectives on a career in academic pharmacy, over half stated the program positively influenced pursuit of such a career. This reinforces the importance of mentorship for those interested in or new to academic pharmacy.

Faculty and Peer Influences on Academic Integrity: College Cheating in Romania

Science.gov (United States)

Teodorescu, Daniel; Andrei, Tudorel

2009-01-01

The purpose of this research was to examine student perceptions of academic integrity among faculty and peers at a sample of public universities in Romania. The study explores the factors that influence academic dishonesty among college students and compares the relative importance of faculty influences and peer influences on students' intent to…

Charge injection and accumulation in organic light-emitting diode with PEDOT:PSS anode

Energy Technology Data Exchange (ETDEWEB)

Weis, Martin, E-mail: martin.weis@stuba.sk [Institute of Electronics and Photonics, Slovak University of Technology, Ilkovičova 3, Bratislava 81219 (Slovakia); Otsuka, Takako; Taguchi, Dai; Manaka, Takaaki; Iwamoto, Mitsumasa, E-mail: iwamoto@ome.pe.titech.ac.jp [Department of Physical Electronics, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8552 (Japan)

2015-04-21

Organic light-emitting diode (OLED) displays using flexible substrates have many attractive features. Since transparent conductive oxides do not fit the requirements of flexible devices, conductive polymer poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) has been proposed as an alternative. The charge injection and accumulation in OLED devices with PEDOT:PSS anodes are investigated and compared with indium tin oxide anode devices. Higher current density and electroluminescence light intensity are achieved for the OLED device with a PEDOT:PSS anode. The electric field induced second-harmonic generation technique is used for direct observation of temporal evolution of electric fields. It is clearly demonstrated that the improvement in the device performance of the OLED device with a PEDOT:PSS anode is associated with the smooth charge injection and accumulation.

Facile Preparation and Enhanced Capacitance of the Ag-PEDOT:PSS/Polyaniline Nanofiber Network for Supercapacitors

International Nuclear Information System (INIS)

Patil, Dipali S.; Pawar, Sachin A.; Kim, Jin Hyeok; Patil, Pramod S.; Shin, Jae Cheol

2016-01-01

Graphical abstract: Fig. shows the steps involved in the development of the AgNW-PEDOT:PSS/PANI electrode. The bright silver nanocubes were observed onto the PANI nanofibers. This means that during the electrodeposition of PANI, there is an electrostatic interaction between AgNWs and PANI; the AgNWs are segmented into the small nanocubes. These nanocubes are distributed equally all over the interconnected network of the PANI nanofibers. This provides a continuous path for the electrons during the charge/discharge process. - Highlights: • Ag-PEDOT:PSS/PANI hybrid nanostructure was prepared. • Dip coating and electrodeposition techniques are used for electrodes preparation. • Symmetric supercapacitor based on AgNW-PEDOT:PSS/PANI was developed. • The positive synergistic effect of AgNW, PEDOT:PSS and PANI was observed. - Abstract: This paper reports the synthesis of a silver − Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)/Polyaniline(Ag-PEDOT:PSS/PANI)hybrid nanostructure using a simple dip coating technique followed by potentiodynamic electrodeposition to achieve an electrochemical supercapacitor with excellent electrochemical performance. In this sandwich type structure, the Ag nanostructure-blended PEDOT: PSS acts as a current collector, where electrons can be transferred easily through this network to the PANI nanofibers and vice versa. The AgNW-PEDOT:PSS/PANI showed a specific capacitance of 643 Fg −1 at 10 mVs −1 and an energy density of 86.19 Whkg −1 at 0.1 mA, indicating the positive synergistic effect of silver nanowires (AgNW), PEDOT:PSS and PANI. The Ag nanostructure incorporated PEDOT:PSS helps to improve the electronic conductivity and the electrochemical stability of the PANI electrodes. Promising electrochemical properties achieved from the measurement of symmetric device demonstrate the ideal capacitive behavior of our prepared electrodes.

Enhanced thermoelectric properties of PEDOT/PSS/Te composite films treated with H{sub 2}SO{sub 4}

Energy Technology Data Exchange (ETDEWEB)

Song, Haijun; Cai, Kefeng, E-mail: kfcai@tongji.edu.cn [Tongji University, Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, School of Materials Science and Engineering (China); Shen, Shirley [CSIRO Manufacturing (Australia)

2016-12-15

Firstly, tellurium (Te) nanorods with a high Seebeck coefficient have been integrated into a conducting polymer PEDOT/PSS to form PEDOT/PSS/Te composite films. The Seebeck coefficient of the PEDOT/PSS/Te (90 wt.%) composite films is ~191 μV/K, which is about 13 times greater than that of pristine PEDOT/PSS. Then, H{sub 2}SO{sub 4} treatment has been used to further tune the thermoelectric properties of the composite films by adjusting the doping level and increasing the carrier concentration. After the acid treatment, the electrical conductivity of the composite films has increased from 0.22 to 1613 S/cm due to the removal of insulating PSS and the structural rearrangement of PEDOT. An optimized power factor of 42.1 μW/mK{sup 2} has been obtained at room temperature for a PEDOT/PSS/Te (80 wt.%) sample, which is about ten times larger than that of the untreated PEDOT/PSS/Te composite film.

Risk Management Challenges in Large-scale Energy PSS

DEFF Research Database (Denmark)

Tegeltija, Miroslava; Oehmen, Josef; Kozin, Igor

2017-01-01

data and representation of the results to the decision makers play an important role. Second, we introduce a selection of alternative, so-called “post-probabilistic”, risk management methods developed across different scientific fields to cope with uncertainty due to lack of knowledge. Possibilities......Probabilistic risk management approaches have a long tradition in engineering. A large variety of tools and techniques based on the probabilistic view of risk is available and applied in PSS practice. However, uncertainties that arise due to lack of knowledge and information are still missing...... for overcoming industrial PSS risk management challenges are suggested through application of post-probabilistic methods. We conclude with the discussion on the importance for the field to consider their application....

Impact of PSS and SVC on the Power System Transient Stability

Directory of Open Access Journals (Sweden)

Mohammed Omar Benaissa

2017-06-01

Full Text Available The Static Var Compensator (SVC is used to improve the stability of the power system because of its role in injecting or absorbing the reactive power in the electrical transmission lines. The Power System Stabilizer (PSS is also a control device which ensures maximum power transfer and thus the stability of the power system enhancement. The PSS has been widely used to damp electromechanical oscillations occur in power systems. If no adequate damping is available, the oscillations will increase leading to instability. The present work is an original contribution to the problem of transient stability in the electrical power system, the authors have made some efforts to illustrate the flexibility and the importance of inserting the SVC alone or with the PSS the fact that maintain the characteristics of the system within acceptable limits in a very short time. The results show that the system has been developed successfully in terms of transient stability in a bi-machine transmission system only with the presence of PSS when a single-phase fault has been occurred, while the presence of SVC is more than essential when a three-phase fault is occurred.

Influence of sedentary lifestyle on academic performance in adolescence: a bibliographical review

Directory of Open Access Journals (Sweden)

José Carlos Escámez Baños

2018-02-01

Full Text Available Adolescence proves to be a key age for acquiring and maintaining healthy habits. Nowadays, numerous research studies link physical activity practice with academic performance, as well as the physical fitness state and the body composition with academic achievement. Objective: Review the grade of influence of physical-sport activity on the variable academic performance and to know the influence of sedentary lifestyle on academic performance. Method: For this purpose, various databases were analyzed, including PubMed and Google Scholar, choosing a total of 75 articles in the first selection, using a total of 18 finally. Results and Conclusions: In terms of results and conclusions, we can see how physical activity practice has a positive influence on academic performance, being the recommended time 30-60 minutes daily.

Nozzle Printed-PEDOT:PSS for Organic Light Emitting Diodes with Various Dilution Rates of Ethanol

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Dai Geon Yoon

2018-01-01

Full Text Available In this study, we investigated the ink formulation of poly(3,4-ethylenedioxythiophene polystyrene sulfonate (PEDOT:PSS as the hole injection layer (HIL in an organic light emitting diode (OLED structure. Generally, in a PEDOT:PSS solution, water is incorporated in the solution for the solution process. However, the fabrication of thin film which contained the water, main solvent, could not easily form by using printing technology except spin-coating process because of the high surface tension of water. On the other hand, mixing PEDOT:PSS solution and ethanol (EtOH, a dilution solvent, could restrain the non-uniform layer that forms by the high surface tension and low volatility of water. Therefore, we printed a PEDOT:PSS solution with various concentrations of EtOH by using a nozzle printer and obtained a uniform pattern. The line width of PEDOT:PSS diluted with 90% (volume ratio ehtanol was measured as about 4 mm with good uniformity with a 0.1 mm nozzle. Also, imaging software and a scanning electron microscope (SEM were used to measure the uniformity of PEDOT:PSS coated on a substrate. Finally, we fabricated a green phosphorescent OLED device with printed-PEDOT:PSS with specific concentrations of EtOH and we achieved a current efficiency of 27 cd/A with uniform quality of luminance in the case of device containing 90% EtOH.

Preparation of Composited Graphene/PEDOT:PSS Film for Its Possible Application in Graphene-based Organic Solar Cells

Institute of Scientific and Technical Information of China (English)

YU; Yue; LI; Meicheng; CHU; Lihua; YU; Hakki; Wodtke; A.M.; ZHAO; Yan; ZHANG; Zhongmo

2015-01-01

The interface between graphene and organic layers is a key factor responsible for the performance of graphene-based organic solar cells(OSCs). In this paper, we focus on coating PEDOT:PSS onto the surface of graphene. We demonstrate two approaches, applying UV/Ozone treatment on graphene and modifying PEDOT:PSS with Zonyl, to get a PEDOT:PSS well-coated graphene film. Our results prove that both methods can be effective to solve the interface issue between graphene and PEDOT: PSS. Thereby it shows a positive application of the composited graphene/PEDOT:PSS film on graphene-based OSCs.

Preparation of Composited Graphene/PEDOT:PSS Film for Its Possible Application in Graphene-based Organic Solar Cells

Institute of Scientific and Technical Information of China (English)

YU Yue; LI Meicheng; CHU Lihua; YU Hakki; Wodtke A M; ZHAO Yan; ZHANG Zhongmo

2015-01-01

The interface between graphene and organic layers is a key factor responsible for the performance of gra-phene-based organic solar cells (OSCs). In this paper, we focus on coating PEDOT:PSS onto the surface of graphene. We demonstrate two approaches, applying UV/Ozone treatment on graphene and modifying PEDOT:PSS with Zonyl, to get a PEDOT:PSS well-coated graphene film . Our results prove that both methods can be effective to solve the interface issue between graphene and PEDOT: PSS. Thereby it shows a positive application of the composited gra-phene/PEDOT:PSS film on graphene-based OSCs.

Oscillation Control in a Synchronous Machine using a Neural based PSS

Directory of Open Access Journals (Sweden)

Sandra Milena Pérez Londoño

2008-01-01

Full Text Available En este artículo se presenta el diseño y la prueba en laboratorio de un estabilizador de potencia (PSS, basado en redes neuronales. La arquitectura propuesta del PSS utiliza dos redes neuronales, la primera es un controlador que efectúa un control suplementario del sistema de excitación, y una segunda red utilizada para mejorar el desempeño del controlador anterior. Para garantizar la correcta operación del PSS propuesto, éste ha sido entrenado utilizando datos obtenidos a partir de varias condiciones de operación de la máquina, y una amplia variedad de disturbios. La efectividad del método propuesto se confirma a partir de los resultados de las pruebas con máquinas síncronas utilizadas en laboratorio.

NiS(NPs)-PEDOT-PSS composite counter electrode for a high efficiency dye sensitized solar cell

Energy Technology Data Exchange (ETDEWEB)

Maiaugree, Wasan [Integrated Nanotechnology Research Center, Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen 40002 (Thailand); Center for Alternative Energy Research and Development, Khon Kaen University, Khon Kaen 40002 (Thailand); Pimparue, Pachara; Jarernboon, Wirat [Integrated Nanotechnology Research Center, Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen 40002 (Thailand); Pimanpang, Samuk [Department of Physics, Faculty of Science, Srinakharinwirot University, Bangkok 10110 (Thailand); Amornkitbamrung, Vittaya [Integrated Nanotechnology Research Center, Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen 40002 (Thailand); Swatsitang, Ekaphan, E-mail: ekaphan@kku.ac.th [Integrated Nanotechnology Research Center, Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen 40002 (Thailand); Center for Alternative Energy Research and Development, Khon Kaen University, Khon Kaen 40002 (Thailand)

2017-06-15

Graphical abstract: Figure(a) and (b) represent models depict PEDOT-PSS counter electrodes of DSSC without and with NiS NPs modification, respectively. The active surface area of PEDOT-PSS polymer can be improved by combining with NiS(NPs). The I-V curves in figure (c) show the superior photovoltaic conversion efficiency of 8.18% for NiS(NPs)/PEDOT-PSS DSSC. - Highlights: • Active surface area of PEDOT-PSS CE can be improved by mixing with NiS(NPs). • Electrocatalytic activity of mixed NiS(NPs)/PEDOT-PSS polymer is also improved. • NiS(NPs)/PEDOT-PSS CE shows a very low charge transfer resistance of 0.46 Ω. • In this work, the high photovoltaic conversion efficiency of 8.18% is achieved. - Abstract: Nickel sulfide (NiS) nanoparticles (NPs) (NiS(NPs)) were prepared by the hydrothermal method. X-ray diffraction (XRD) results indicate the hexagonal structure of NiS(NPs). SEM micrographs reveal the agglomeration of irregular hexagonal – shaped NiS(NPs) with estimated particle size in the range of 50–150 nm. Counter electrodes (CEs) of dye-sensitized solar cells (DSSCs) were prepared by coating the composite slurry of different NiS(NPs) loadings and Poly (3, 4-Ethylendioxythiophene) – Poly (Styrene Sulfonate) (PEDOT-PSS) on fluoride-doped tin oxide (FTO) substrates using a doctor blading technique. Cyclic voltammetry (CV) results indicate that the composites of NiS(NPs) and PEDOT-PSS (NiS(NPs)/PEDOT-PSS) films could function as a catalyst for I{sub 3}{sup −} reduction with a maximum cell efficiency of 8.18% for a cell of 0.3 g NiS(NPs) loading.

Influence of ZnO:Al, MoO3 and PEDOT:PSS on efficiency in standard and inverted polymer solar cells based on polyazomethine and poly(3-hexylthiophene)

International Nuclear Information System (INIS)

Iwan, Agnieszka; Palewicz, Marcin; Tazbir, Igor; Boharewicz, Bartosz; Pietruszka, Rafal; Filapek, Michal; Wojtkiewicz, Jacek; Witkowski, Bartłomiej Sławomir; Granek, Filip; Godlewski, Marek

2016-01-01

This paper is devoted to the development of standard and inverted polymer solar cells based on polyazomethine (PAZ-Car-TPA), poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C 61 butyric acid methyl ester (PCBM). We analyzed the influence of: (i) PEDOT:PSS or MoO 3 as a hole transporting layer in standard devices, (ii) aluminum doping level (from 0 to 3.7%) in ZnO (obtained by atomic layer deposition, ALD) applied as an electron transporting layer in inverted solar cells and (iii) the method applied to obtain ZnO layer (ALD or sol-gel) on its photovoltaic properties. The best device configuration is ITO/AZO (3% Al)/P3HT:PCBM/MoO 3 /Ag which exhibits a power conversion efficiency of 1.51% under about 100 mW/cm 2 AM 1.5 G simulated solar emission. Devices were additionally tested by electrochemical impedance spectroscopy. HOMO-LUMO levels of PAZ-Car-TPA and its mixture with HCl, H 2 SO 4 , p-toluenesulfonic acid, PEDOT:PSS and water were analyzed by cyclic voltammetry and quantum mechanical calculations using Density Functional Theory method.

Preparation of 2D MoSe2/PEDOT:PSS composite and its thermoelectric properties

Science.gov (United States)

Li, Xia; Liu, Congcong; Wang, Tongzhou; Wang, Wenfang; Wang, Xiaodong; Jiang, Qinglin; Jiang, Fengxing; Xu, Jingkun

2017-11-01

Nowadays, inorganic/polymer composites have attracted significant interest in thermoelectric field, since the composite materials usually achieve their respective advantages complementary to each other. In this work, molybdenum diselenide (MoSe2) was synthesized by a facile hydrothermal method. Solution processible two-dimensional (2D) MoSe2 nanosheets (NSs) were successfully obtained using dimethylsulfoxide (DMSO) solvent or lithium intercalation procedure. Combined with Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), MoSe2/PEDOT:PSS composite thin films were fabricated by direct vacuum-filtration method. Thermoelectric properties of composite thin films were investigated systematically and found that 2D MoSe2 NSs and PEDOT:PSS have the synergistic effect on improving thermoelectric properties. The maximum power factor was calculated to be 48.6 µW m-1 K-2 with 5 wt% 2D MoSe2 NSs embedding into PEDOT:PSS matrix, which is almost 69% higher than that of pure PEDOT:PSS. These results demonstrate that 2D inorganic/polymer composite method is one of promising strategies to get high-performance polymer-based thermoelectric composites.

Comparison of intelligent fuzzy based AGC coordinated PID controlled and PSS controlled AVR system

Energy Technology Data Exchange (ETDEWEB)

Mukherjee, V. [Department of Electrical Engineering, Asansol Engineering College, Asansol, West Bengal (India); Ghoshal, S.P. [Department of Electrical Engineering, National Institute of Technology, Durgapur, West Bengal (India)

2007-11-15

This paper attempts to investigate the performance of intelligent fuzzy based coordinated control of the Automatic Generation Control (AGC) loop and the excitation loop equipped with Proportional Integral Derivative (PID) controlled Automatic Voltage Regulator (AVR) system and Power System Stabilizer (PSS) controlled AVR system. The work establishes that PSS controlled AVR system is much more robust in dynamic performance of the system over a wide range of system operating configurations. Thus, it is revealed that PSS equipped AVR is much more superior than PID equipped AVR in damping the oscillation resulting in improved transient response. The paper utilizes a novel class of Particle Swarm Optimization (PSO) termed as Craziness based Particle Swarm Optimization (CRPSO) as optimizing tool to get optimal tuning of PSS parameters as well as the gains of PID controllers. For on-line, off-nominal operating conditions Takagi Sugeno Fuzzy Logic (TSFL) has been applied to obtain the off-nominal optimal gains of PID controllers and parameters of PSS. Implementation of TSFL helps to achieve very fast dynamic response. Fourth order model of generator with AVR and high gain thyristor excitation system is considered for PSS controlled system while normal gain exciter is considered for PID controlled system. Simulation study also reveals that with high gain exciter, PID control is not at all effective. Transient responses are achieved by using modal analysis. (author)

Gender Influence On Managerial Efficiency Of Academic Librarians ...

African Journals Online (AJOL)

This study discusses the influences of gender on managerial efficiency of academic librarians in Nigeria. The rationale for the study was to investigate if gender grouping has an influence on the managerial competence of librarians in Nigeria. The total enumeration sampling technique with a questionnaire instrument was ...

Open to Influence: What Counts as Academic Influence in Scholarly Networked "Twitter" Participation

Science.gov (United States)

Stewart, Bonnie

2015-01-01

Within the academy, signals of a scholar's academic influence are made manifest in indices like the "h"-index, which rank output. In open scholarly networks, however, signals of influence are less codified, and the ways in which they are enacted and understood have yet to be articulated. Yet the influence scholars cultivate in open…

Enhancement of UV photodetector properties of ZnO nanorods/PEDOT:PSS Schottky junction by NGQD sensitization along with conductivity improvement of PEDOT:PSS by DMSO additive

Science.gov (United States)

Dhar, Saurab; Majumder, Tanmoy; Chakraborty, Pinak; Mondal, Suvra Prakash

2018-04-01

Schottky junction ultraviolet (UV) photodetector was fabricated by spin coating a hole conducting polymer, poly 3,4-ethylenedioxythiophene: polystyrene sulfonate (PEDOT:PSS) on hydrothermally grown zinc oxide (ZnO) nanorod arrays. The UV detector performance was significantly improved two step process. Firstly, ZnO nanorods were modified by sensitizing N doped grapheme quantum dots (NGQDs) for better photoresponce behavior. Afterwards, the junction properties as well as photoresponse was enhanced by modifying electrical conductivity of PEDOT:PSS layer with organic solvent (DMSO). Our NGQD decorated ZnO NRs/DMSO-PEDOT:PSS Schottky junction device demonstrated superior external quantum efficiency (EQE ˜ 90063 %) and responsivity (Rλ˜247 A/W) at 340 nm wavelength and -1V external bias. The response and recovery times of the final photodetector device was very fast compared to GQD as well as NGQD modified and pristine ZnO nanorod based detectors.

Effects of pentacene-doped PEDOT:PSS as a hole-conducting layer on the performance characteristics of polymer photovoltaic cells.

Science.gov (United States)

Kim, Hyunsoo; Lee, Jungrae; Ok, Sunseong; Choe, Youngson

2012-01-05

We have investigated the effect of pentacene-doped poly(3,4-ethylenedioxythiophene:poly(4-styrenesulfonate) [PEDOT:PSS] films as a hole-conducting layer on the performance of polymer photovoltaic cells. By increasing the amount of pentacene and the annealing temperature of pentacene-doped PEDOT:PSS layer, the changes of performance characteristics were evaluated. Pentacene-doped PEDOT:PSS thin films were prepared by dissolving pentacene in 1-methyl-2-pyrrolidinone solvent and mixing with PEDOT:PSS. As the amount of pentacene in the PEDOT:PSS solution was increased, UV-visible transmittance also increased dramatically. By increasing the amount of pentacene in PEDOT:PSS films, dramatic decreases in both the work function and surface resistance were observed. However, the work function and surface resistance began to sharply increase above the doping amount of pentacene at 7.7 and 9.9 mg, respectively. As the annealing temperature was increased, the surface roughness of pentacene-doped PEDOT:PSS films also increased, leading to the formation of PEDOT:PSS aggregates. The films of pentacene-doped PEDOT:PSS were characterized by AFM, SEM, UV-visible transmittance, surface analyzer, surface resistance, and photovoltaic response analysis.

Factors Influencing American Plastic Surgery Residents Toward an Academic Career.

Science.gov (United States)

Chetta, Matthew D; Sugg, Kristoffer B; Diaz-Garcia, Rafael J; Kasten, Steven J

2018-02-01

Plastic surgery residency program directors have an interest in recruiting applicants who show an interest in an academic practice. Medical school achievements (ie, United States Medical Licensing Examination® scores, publications, and Alpha Omega Alpha status) are metrics assessed to grade applicants but may not correlate with ultimately choosing an academic career. This study was designed to investigate factors influencing residents' choices for or against academic careers. A 25-item online questionnaire was designed to measure baseline interest in academic plastic surgery and factors that influence decisions to continue on or abandon that career path. This questionnaire was disseminated to the integrated/combined plastic surgery residents during the 2013 to 2014 academic year. One hundred twenty-five respondents indicated that they were currently interested in pursuing academic practice (n = 78) or had lost interest in academic practice (n = 47). Among all respondents, 92.8% (n = 116) stated they were interested in academic careers at the time of residency application, but one-third (n = 41) subsequently lost interest. Those residents who retained interest in academic careers indicated resident/medical student educational opportunities (57%) and complexity of patients (52%) as reasons. Those who lost interest cited a lack of autonomy (43%), publishing requirements (32%), and income discrepancy (26%) as reasons. Many residents report losing interest in academics during residency. Traditional metrics valued in the recruitment process may not serve as positive predictors of an academic career path. Reasons why residents lose interest are not easily correctable, but mentorship, adequate career counseling, and research opportunities during training remain factors that can be addressed across all residency programs.

Nonvolatile write-once-read-many-times memory device with functionalized-nanoshells/PEDOT:PSS nanocomposites

International Nuclear Information System (INIS)

Avila-Nino, J.A.; Segura-Cardenas, E.; Sustaita, A.O.; Cruz-Cruz, I.; Lopez-Sandoval, R.; Reyes-Reyes, M.

2011-01-01

We have investigated the memory effect of the nanocomposites of functionalized carbon nanoshells (f-CNSs) mixed with poly(3,4-ethylenedioxythiophene) doped with polystyrenesulfonate (PEDOT:PSS) polymer. The f-CNSs were synthesized by the spray pyrolysis method and functionalized in situ with functional groups (OH, COOH, C-H, C-OH) with the aim of improving their compatibility in the aqueous dispersion of PEDOT:PSS. The current-voltage (I-V) sweep curves at room temperature for the Al/f-CNSs, for certain concentrations range, embedded in a PEDOT:PSS layer/Al devices showed electrical bistability for write-once-read-many-times (WORM) memory devices. The memory effect observed in the devices can be explained due to the existence of trapped charges in the f-CNSs/PEDOT:PSS layer. The carrier transport mechanisms for the memory devices is studied and discussed.

Nonvolatile write-once-read-many-times memory device with functionalized-nanoshells/PEDOT:PSS nanocomposites

Energy Technology Data Exchange (ETDEWEB)

Avila-Nino, J.A.; Segura-Cardenas, E. [Universidad Autonoma de San Luis Potosi, Instituto de Investigacion en Comunicacion Optica, Alvaro Obregon 64 Zona Centro, 78000 SLP (Mexico); Sustaita, A.O. [Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la presa San Jose 2055, CP 78216, San Luis Potosi (Mexico); Cruz-Cruz, I. [Universidad Autonoma de San Luis Potosi, Instituto de Investigacion en Comunicacion Optica, Alvaro Obregon 64 Zona Centro, 78000 SLP (Mexico); Lopez-Sandoval, R. [Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la presa San Jose 2055, CP 78216, San Luis Potosi (Mexico); Reyes-Reyes, M., E-mail: reyesm@iico.uaslp.mx [Universidad Autonoma de San Luis Potosi, Instituto de Investigacion en Comunicacion Optica, Alvaro Obregon 64 Zona Centro, 78000 SLP (Mexico)

2011-03-25

We have investigated the memory effect of the nanocomposites of functionalized carbon nanoshells (f-CNSs) mixed with poly(3,4-ethylenedioxythiophene) doped with polystyrenesulfonate (PEDOT:PSS) polymer. The f-CNSs were synthesized by the spray pyrolysis method and functionalized in situ with functional groups (OH, COOH, C-H, C-OH) with the aim of improving their compatibility in the aqueous dispersion of PEDOT:PSS. The current-voltage (I-V) sweep curves at room temperature for the Al/f-CNSs, for certain concentrations range, embedded in a PEDOT:PSS layer/Al devices showed electrical bistability for write-once-read-many-times (WORM) memory devices. The memory effect observed in the devices can be explained due to the existence of trapped charges in the f-CNSs/PEDOT:PSS layer. The carrier transport mechanisms for the memory devices is studied and discussed.

Systematic Approach to Formulate PSS Development Project Proposals in the Fuzzy Front End

DEFF Research Database (Denmark)

Barquet, Ana Paula B.; Pigosso, Daniela Cristina Antelmi; Rozenfeld, Henrique

2013-01-01

be considered by companies during this definition. The systematization of PSS attributes may help increase the knowledge about different PSS projects that can emerge in the front end, thus leading to the discovery of opportunities that are not apparent in the existing business models and give rise to new ideas...

Highly Conductive PEDOT:PSS Films with 1,3-Dimethyl-2-Imidazolidinone as Transparent Electrodes for Organic Light-Emitting Diodes.

Science.gov (United States)

Kim, Jin Hee; Joo, Chul Woong; Lee, Jonghee; Seo, Yoon Kyung; Han, Joo Won; Oh, Ji Yoon; Kim, Jong Su; Yu, Seunggun; Lee, Jae Hyun; Lee, Jeong-Ik; Yun, Changhun; Choi, Bum Ho; Kim, Yong Hyun

2016-09-01

Highly conductive poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) ( PSS) films as transparent electrodes for organic light-emitting diodes (OLEDs) are doped with a new solvent 1,3-dimethyl-2-imidazolidinone (DMI) and are optimized using solvent post-treatment. The DMI doped PSS films show significantly enhanced conductivities up to 812.1 S cm(-1) . The sheet resistance of the PSS films doped with DMI is further reduced by various solvent post-treatment. The effect of solvent post-treatment on DMI doped PSS films is investigated and is shown to reduce insulating PSS in the conductive films. The solvent posttreated PSS films are successfully employed as transparent electrodes in white OLEDs. It is shown that the efficiency of OLEDs with the optimized DMI doped PSS films is higher than that of reference OLEDs doped with a conventional solvent (ethylene glycol). The results present that the optimized PSS films with the new solvent of DMI can be a promising transparent electrode for low-cost, efficient ITO-free white OLEDs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The Vietnamese version of the Perceived Stress Scale (PSS-10): Translation equivalence and psychometric properties among older women.

Science.gov (United States)

Dao-Tran, Tiet-Hanh; Anderson, Debra; Seib, Charrlotte

2017-02-06

The Perceived Stress Scale 10 item (PSS-10) has been translated into more than 20 languages and used widely in different populations. Yet, to date, no study has tested psychometric properties of the instrument among older women and there is no Vietnamese version of the instrument. This study translated the PSS-10 into Vietnamese and assessed Vietnamese version of the Perceived Stress Scale 10 items (V-PSS-10) for translation equivalence, face validity, construct validity, correlations, internal consistency reliability, and test-retest reliability among 473 women aged 60 and over. The study found that V-PSS-10 retained the original meaning and was understood by Vietnamese older women. An exploratory factor analysis of the V-PSS-10 yielded a two-factor structure, and these two factors were significantly correlated (0.56, p < .01) with all item loadings exceeded .50. The V-PSS-10 score was positively correlated with general sleep disturbance (ρ = .12, p < .05), CES-D score for depression symptoms (ρ = .60, p < .01), and negatively correlated with mental (ρ = -.46, p < .01), and physical health scores (ρ = -.19, p < .01). The Cronbach's alpha for the V-PSS-10 was .80, and the test-retest correlation at one month's interval was .43. Findings from this study suggest that the V-PSS-10 has acceptable validity and reliability levels among older women. The V-PSS-10 can be used to measure perceived stress in future research and practice. However, future research would be useful to further endorse the validity and reliability of the V-PSS-10.

Efficient and Air-Stable Planar Perovskite Solar Cells Formed on Graphene-Oxide-Modified PEDOT:PSS Hole Transport Layer

Science.gov (United States)

Luo, Hui; Lin, Xuanhuai; Hou, Xian; Pan, Likun; Huang, Sumei; Chen, Xiaohong

2017-10-01

As a hole transport layer, PEDOT:PSS usually limits the stability and efficiency of perovskite solar cells (PSCs) due to its hygroscopic nature and inability to block electrons. Here, a graphene-oxide (GO)-modified PEDOT:PSS hole transport layer was fabricated by spin-coating a GO solution onto the PEDOT:PSS surface. PSCs fabricated on a GO-modified PEDOT:PSS layer exhibited a power conversion efficiency (PCE) of 15.34%, which is higher than 11.90% of PSCs with the PEDOT:PSS layer. Furthermore, the stability of the PSCs was significantly improved, with the PCE remaining at 83.5% of the initial PCE values after aging for 39 days in air. The hygroscopic PSS material at the PEDOT:PSS surface was partly removed during spin-coating with the GO solution, which improves the moisture resistance and decreases the contact barrier between the hole transport layer and perovskite layer. The scattered distribution of the GO at the PEDOT:PSS surface exhibits superior wettability, which helps to form a high-quality perovskite layer with better crystallinity and fewer pin holes. Furthermore, the hole extraction selectivity of the GO further inhibits the carrier recombination at the interface between the perovskite and PEDOT:PSS layers. Therefore, the cooperative interactions of these factors greatly improve the light absorption of the perovskite layer, the carrier transport and collection abilities of the PSCs, and especially the stability of the cells.

Electromechanical properties of polyamide/lycra fabric treated with PEDOT:PSS

Science.gov (United States)

Tadesse, M. G.; Mengistie, D. A.; Loghin, C.; Chen, Y.; Wang, L.; Catalin, D.; Müller, C.; Nierstrasz, V.

2017-10-01

One of the challenges in smart textiles is to develop suitable multifunctional materials that can address simultaneously several characteristics such as durability, stretchability, lightweight, and conductivity. Conductive polymers which showed success in different technological fields like polymer solar cells and light emitting diodes are promising in many smart textile applications. In this work, we treated a common polyamide/lycra knitted fabric with PEDOT:PSS for stretchable e-textiles. PEDOT:PSS, with DMSO as a conductivity enhancer and different ratios of water-based polyurethane dispersions as a binder, was applied to the fabric with simple immersion and coating applications. The effect of different application methods and binder ratio on the surface resistance of the fabric was monitored with four point probe electrical surface resistance measurement systems. Samples prepared by immersion technique are more uniform and have higher conductivity than those prepared by a coating technique. SEM images showed that PEDOT:PSS is incorporated into the structure in the immersion method while in the coating it is majorly present on the surface of the fabric. The tensile measurement showed that the acidic PEDOT:PSS and polyurethane dispersion coating has no adverse effect on the tensile strength of the fabric. The coated samples can be stretched up to 700% while still reasonably conductive. The resistance increases only by a small amount when samples were stretched cyclically by stretching 100%. Generally, samples prepared by the immersion method maintained better conductivity while stretching than those by a coating method. The washing fastness of the samples was also assessed.

A paper-based electrode using a graphene dot/PEDOT:PSS composite for flexible solar cells

KAUST Repository

Lee, Chuan-Pei

2017-04-22

We have synthesized a metal-free composite ink that contains graphene dots (GDs) and poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) that can be used on paper to serve as the counter electrode in a flexible dye-sensitized solar cell (DSSC). This paper-based GD/PEDOT:PSS electrode is low-cost, light-weight, flexible, environmentally friendly, and easy to cut and process for device fabrication. We determined the GD/PEDOT:PSS composite effectively fills the dense micro-pores in the paper substrate, which leads to improved carrier transport in the electrode and a 3-fold enhanced cell efficiency as compared to the paper electrode made with sputtered Pt. Moreover, the DSSC with the paper electrode featuring the GD/PEDOT:PSS composite did not fail in photovoltaic tests even after bending the electrode 150 times, whereas the device made with the Pt-based paper electrode decreased in efficiency by 45% after such manipulation. These exceptional properties make the metal-free GD/PEDOT:PSS composite ink a promising electrode material for a wide variety of flexible electronic applications.

Conductivity, work function, and environmental stability of PEDOT:PSS thin films treated with sorbitol

NARCIS (Netherlands)

Nardes, A.M.; Kemerink, M.; Kok, de M.M.; Vinken, E.; Maturova, K.; Janssen, R.A.J.

2008-01-01

The electrical properties of poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) thin films deposited from aqueous dispersion using different concentrations of sorbitol have been studied in detail. Although it is well known that sorbitol enhances the conductivity of PEDOT:PSS thin

Theoretical considerations regarding the existence of PsO and PsS+

International Nuclear Information System (INIS)

Farazdel, A.; Cade, P.E.

1977-01-01

It has been proposed from experimental studies and in analogy with hydrogen compounds that PsO may be an entity of some importance, or an intermediate, in the reaction of positronium, Ps, with aqueous oxyacid species such as H 2 PO 4 - , HSO 4 - , ClO 4 - , and NO 3 - . This communication explores the stability of PsO and PsS, or [O - :e + ] and [S - :e + ], respectively, relative to dissociation into Ps and O( 3 P) or S( 3 P) on the basis of restricted Hartree-Fock calculations for the PsO and PsS systems and certain correlation correction arguments. A reasonable lower estimate of the dissociation energy to Y+Ps of >-0.47 eV for PsO and >0.70 eV for PsS is obtained. It is suggested that a modest correlation correction to the positron affinity (PA) of O - would very probably lead to a bound state system for PsO. (Auth.)

Academic musculoskeletal radiology: influences for gender disparity.

Science.gov (United States)

Qamar, Sadia R; Khurshid, Kiran; Jalal, Sabeena; Bancroft, Laura; Munk, Peter L; Nicolaou, Savvas; Khosa, Faisal

2018-03-01

Research productivity is one of the few quintessential gauges that North American academic radiology departments implement to determine career progression. The rationale of this study is to quantify the relationship of gender, research productivity, and academic advancements in the musculoskeletal (MSK) radiology to account for emerging trends in workforce diversity. Radiology residency programs enlisted in the Fellowship and Residency Electronic Interactive Database (FREIDA), Canadian Resident Matching Service (CaRMS) and International Skeletal Society (ISS) were searched for academic faculty to generate the database for gender and academic profiles of MSK radiologists. Bibliometric data was collected using Elsevier's SCOPUS archives, and analyzed using Stata version 14.2. Among 274 MSK radiologists in North America, 190 (69.34%) were men and 84 (30.66%) were women, indicating a statistically significant difference (χ2 = 6.34; p value = 0.042). The available number of female assistant professors (n = 50) was more than half of the male assistant professors (n = 88), this ratio however, plummeted at higher academic ranks, with only one-fourth of women (n = 11) professors compared to men (n = 45). The male MSK radiologist had 1.31 times the odds of having a higher h-index, keeping all other variables constant. The trend of gender disparity exists in MSK radiology with significant underrepresentation of women in top tiers of academic hierarchy. Even with comparable h-indices, at the lower academic ranks, a lesser number of women are promoted relative to their male colleagues. Further studies are needed to investigate the degree of influence research productivity has, in determining academic advancement of MSK radiologists.

Damping Torsional Torques in Turbine-Generator Shaft by Novel PSS Based on Genetic Algorithm and Fuzzy Logic

Directory of Open Access Journals (Sweden)

Abbas Shoulaie

2010-07-01

Full Text Available Torsional torques on turbine-generator shaft which are yields of disturbances in power systems, can reduce the useful lifetime of shaft. In this paper, these oscillations will be damped and controlled by novel Power System Stabilizers (PSSs. Complex PSS which is used in this paper will act on the excitation system in generator set and also on the controller of in High Voltage Direct Current (HVDC system. This PSS uses three terms (generator angle deviation, frequency oscillation and capacitor voltage deviation in HVDC system of the study system which includes two ties AC and DC. This is the reason that this PSS is named novel one against the conventional PSSs. In order to adjust the PSS parameters to damp the oscillations, genetic algorithm is used. To improve the application of this PSS, fuzzy logic control methods are also used which has notable effect on controlling the oscillations in study system. The simulation results show the effectiveness of designed PSS in controlling the torsional torques in turbine-generator shaft.

Psychometric properties of the Perceived Stress Scale (PSS: measurement invariance between athletes and non-athletes and construct validity

Directory of Open Access Journals (Sweden)

Yi-Hsiang Chiu

2016-12-01

Full Text Available Background Although Perceived Stress Scale (PSS, Cohen, Kamarack & Mermelstein, 1983 has been validated and widely used in many domains, there is still no validation in sports by comparing athletes and non-athletes and examining related psychometric indices. Purpose The purpose of this study was to examine the measurement invariance of PSS between athletes and non-athletes, and examine construct validity and reliability in the sports contexts. Methods Study 1 sampled 359 college student-athletes (males = 233; females = 126 and 242 non-athletes (males = 124; females = 118 and examined factorial structure, measurement invariance and internal consistency. Study 2 sampled 196 student-athletes (males = 139, females = 57, Mage = 19.88 yrs, SD = 1.35 and examined discriminant validity and convergent validity of PSS. Study 3 sampled 37 student-athletes to assess test-retest reliability of PSS. Results Results found that 2-factor PSS-10 fitted the model the best and had appropriate reliability. Also, there was a measurement invariance between athletes and non-athletes; and PSS positively correlated with athletic burnout and life stress but negatively correlated with coping efficacy provided evidence of discriminant validity and convergent validity. Further, the test-retest reliability for PSS subscales was significant (r = .66 and r = .50. Discussion It is suggested that 2-factor PSS-10 can be a useful tool in assessing perceived stress either in sports or non-sports settings. We suggest future study may use 2-factor PSS-10 in examining the effects of stress on the athletic injury, burnout, and psychiatry disorders.

The Thai version of the PSS-10: An Investigation of its psychometric properties.

Science.gov (United States)

Wongpakaran, Nahathai; Wongpakaran, Tinakon

2010-06-12

Among the stress instruments that measure the degree to which life events are perceived as stressful, the Perceived Stress Scale (PSS) is widely used. The goal of this study was to examine the psychometric properties of a Thai version of the PSS-10 (T-PSS-10) with a clinical and non-clinical sample. Internal consistency, test-retest reliability, concurrent validity, and the factorial structure of the scale were tested. A total sample of 479 adult participants was recruited for the study: 368 medical students and 111 patients from two hospitals in Northern Thailand. The T-PSS-10 was used along with the Thai version of State Trait Anxiety Inventory (STAI), the Thai Version of the Rosenberg Self-Esteem Scale (RSES), and the Thai Depression Inventory (TDI). Exploratory Factor Analysis (EFA) yielded 2 factors with eigenvalues of 5.05 and 1.60, accounting for 66 percent of variance. Factor 1 consisted of 6 items representing "stress"; whereas Factor 2 consisted of 4 items representing "control". The item loadings ranged from 0.547 to 0.881. Investigation of the fit indices associated with Maximum Likelihood (ML) estimation revealed that the two-factor solution was adequate [chi2 = 35.035 (df = 26, N = 368, p reliability. The Thai version of the PSS-10 demonstrated excellent goodness-of-fit for the two factor solution model, as well as good reliability and validity for estimating the level of stress perception with a Thai population. Limitations of the study are discussed.

Functional solid additive modified PEDOT:PSS as an anode buffer layer for enhanced photovoltaic performance and stability in polymer solar cells

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Xu, Binrui; Gopalan, Sai-Anand; Gopalan, Anantha-Iyengar; Muthuchamy, Nallal; Lee, Kwang-Pill; Lee, Jae-Sung; Jiang, Yu; Lee, Sang-Won; Kim, Sae-Wan; Kim, Ju-Seong; Jeong, Hyun-Min; Kwon, Jin-Beon; Bae, Jin-Hyuk; Kang, Shin-Won

2017-01-01

Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is most commonly used as an anode buffer layer in bulk-heterojunction (BHJ) polymer solar cells (PSCs). However, its hygroscopic and acidic nature contributes to the insufficient electrical conductivity, air stability and restricted photovoltaic (PV) performance for the fabricated PSCs. In this study, a new multifunctional additive, 2,3-dihydroxypyridine (DOH), has been used in the PEDOT: PSS buffer layer to obtain modified properties for PEDOT: PSS@DOH and achieve high PV performances. The electrical conductivity of PEDOT:PSS@DOH films was markedly improved compared with that of PEDOT:PSS. The PEDOT:PSS@DOH film exhibited excellent optical characteristics, appropriate work function alignment, and good surface properties in BHJ-PSCs. When a poly(3-hexylthiohpene):[6,6]-phenyl C61-butyric acid methyl ester blend system was applied as the photoactive layer, the power conversion efficiency of the resulting PSCs with PEDOT:PSS@DOH(1.0%) reached 3.49%, outperforming pristine PEDOT:PSS, exhibiting a power conversion enhancement of 20%. The device fabricated using PEDOT:PSS@DOH (1.0 wt%) also exhibited improved thermal and air stability. Our results also confirm that DOH, a basic pyridine derivative, facilitates adequate hydrogen bonding interactions with the sulfonic acid groups of PSS, induces the conformational transformation of PEDOT chains and contributes to the phase separation between PEDOT and PSS chains. PMID:28338088

Fully Textile, PEDOT:PSS Based Electrodes for Wearable ECG Monitoring Systems.

Science.gov (United States)

Pani, Danilo; Dessi, Alessia; Saenz-Cogollo, Jose F; Barabino, Gianluca; Fraboni, Beatrice; Bonfiglio, Annalisa

2016-03-01

To evaluate a novel kind of textile electrodes based on woven fabrics treated with PSS, through an easy fabrication process, testing these electrodes for biopotential recordings. Fabrication is based on raw fabric soaking in PSS using a second dopant, squeezing and annealing. The electrodes have been tested on human volunteers, in terms of both skin contact impedance and quality of the ECG signals recorded at rest and during physical activity (power spectral density, baseline wandering, QRS detectability, and broadband noise). The electrodes are able to operate in both wet and dry conditions. Dry electrodes are more prone to noise artifacts, especially during physical exercise and mainly due to the unstable contact between the electrode and the skin. Wet (saline) electrodes present a stable and reproducible behavior, which is comparable or better than that of traditional disposable gelled Ag/AgCl electrodes. The achieved results reveal the capability of this kind of electrodes to work without the electrolyte, providing a valuable interface with the skin, due to mixed electronic and ionic conductivity of PSS. These electrodes can be effectively used for acquiring ECG signals. Textile electrodes based on PSS represent an important milestone in wearable monitoring, as they present an easy and reproducible fabrication process, very good performance in wet and dry (at rest) conditions and a superior level of comfort with respect to textile electrodes proposed so far. This paves the way to their integration into smart garments.

Influence of teachers' competence on students academic ...

African Journals Online (AJOL)

This study investigated the influence of teachers' competence on students; academic performance in senior secondary school chemistry. A random sampling technique was used to select 6 secondary schools out of 12 secondary schools in Yala Local Government Area of Cross River State. 200 students, 20 teachers and 6 ...

influence of teachers' competence on students academic ...

African Journals Online (AJOL)

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This study investigated the influence of teachers' competence on students; academic performance in senior secondary school chemistry. A random sampling technique was used to select 6 secondary schools out of 12 secondary schools in Yala Local Government Area of Cross River State. 200 students, 20 teachers and 6 ...

Thin film free-standing PEDOT:PSS/SU8 bilayer microactuators

International Nuclear Information System (INIS)

Taccola, S; Greco, F; Mazzolai, B; Mattoli, V; Jager, E W H

2013-01-01

Several smart active materials have been proposed and tested for the development of microactuators. Among these, conjugated polymers are of great interest because miniaturization improves their electrochemical properties, such as increasing the speed and stress output of microactuators, with respect to large-scale actuators. Recently we developed a novel fabrication process to obtain robust free-standing conductive ultra-thin films made of the conjugated polymer poly(3, 4-ethylenedioxythiophene) doped with the polyanion poly(styrenesulfonate) (PEDOT:PSS). These conductive free-standing nanofilms, with thicknesses ranging between a few tens to several hundreds of nm, allow the realisation of new all polymer microactuators using facile microfabrication methods. Here, we report a novel processing method for manufacturing all polymer electrochemical microactuators. We fabricated and patterned free-standing PEDOT:PSS/SU8 bilayer microactuators in the form of microfingers of a variety of lengths using adapted microfabrication procedures. By imposing electrochemical oxidation/reduction cycles on the PEDOT:PSS we were able to demonstrate reversible actuation of the microactuators resulting in bending of the microfingers. A number of possible applications can be envisaged for these small, soft actuators, such as microrobotics and cell manipulation. (technical note)

Substrate treatment and drying conditions effect on the properties of roll-to-roll gravure printed PEDOT:PSS thin films

International Nuclear Information System (INIS)

Koidis, C.; Logothetidis, S.; Kapnopoulos, C.; Karagiannidis, P.G.; Laskarakis, A.; Hastas, N.A.

2011-01-01

Highlights: → Drying conditions effect on the optical, electrical and structural characteristics of R2R gravure printed PEDOT:PSS thin films → Insight on microstructural, compositional and electrical characteristics of the PEDOT:PSS films by Spectroscopic Ellipsometry combined with the AFM results → Drying temperature increase leads to less remained water volume fraction, smaller particles, lower film roughness and finally better conductivity → Transformation of spherical particles in solution to pancakes in thin films is attributed to the drying process → The increase of corona efficiency leads to a deeper PET surface modification without affecting the adhesion of PEDOT:PSS - Abstract: The optical, structural and electrical properties of poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonic acid) (PEDOT:PSS) thin films printed by roll-to-roll gravure have been investigated. Corona treatment has been applied to enhance the adhesion of PEDOT:PSS on PolyEthylene Terephthalate (PET) web. It has been found that there was a stronger in-depth surface modification of PET with the increase of corona efficiency; however, the adhesion of PEDOT:PSS was not actually affected. Also, Spectroscopic Ellipsometry and Atomic Force Microscopy have been used to extract information on the mechanisms that define PEDOT:PSS properties. The increase of the drying temperature of the PEDOT:PSS films has been found to reduce the remaining water inside the films and lead to the decrease of the PEDOT:PSS particles size.

The role of sleep in predicting college academic performance: is it a unique predictor?

Science.gov (United States)

Taylor, Daniel J; Vatthauer, Karlyn E; Bramoweth, Adam D; Ruggero, Camilo; Roane, Brandy

2013-01-01

Few studies have looked at the predictability of academic performance (i.e., cumulative grade point average [GPA]) using sleep when common nonsleep predictors of academic performance are included. This project studied psychological, demographic, educational, and sleep risk factors of decreased academic performance in college undergraduates. Participants (N = 867) completed a questionnaire packet and sleep diary. It was hypothesized that low total sleep time (TST), increased sleep onset latency, later bedtimes, later wake times, and TST inconsistency would predict decreased academic performance. The most significant predictors of academic performance were high school GPA, standardized test scores (i.e., SAT/ACT), TST, time awake before arising (TWAK), TST inconsistency, and the quadratic terms of perceived stress (PSS) and TST.

Effect of Pedot-Pss on Electrical and Photovoltaic Properties of ITO/MEH-PPV:PCBM/Al Organic Diodes

International Nuclear Information System (INIS)

Gunduz, B.

2008-01-01

The photovoltaic and electrical properties of ITO/MEH-PPV:PCBM/Al and ITO/PEDOT-PSS/MEHPPV:PCBM/Al organic diodes have been investigated. The ideality factor, series resistance and shunt resistance values of ITO/MEH-PPV:PCBM/Al and ITO/PEDOT-PSS/MEHPPV:PCBM/Al diodes were found to be 4.6, 6.84x10 6 Ω, 2.2x10 8 Ω and 4.02, 5.8x10 5 Ω, 2x10 7 Ω respectively. The electronic parameters of the ITO/MEH-PPV:PCBM/Al diode were improved using PEDOT-PSS conducting polymer. ITO/MEH-PPV:PCBM/Al and ITO/PEDOT-PSS/MEHPPV:PCBM/Al organic diodes indicate a photovoltaic behaviour with a maximum open circuit voltage V o c and short-circuit current I s c. The photoconductivity sensitivity and responsivity properties of the organic diodes have been characterized by transient-current measurements. The obtained electrical and photovoltaic results indicate that ITO/MEH-PPV:PCBM/Al and ITO/PEDOT-PSS/MEHPPV:PCBM/Al structures are the organic photodiodes with calculated electronic parameters and the electrical properties of the ITO/MEH-PPV:PCBM/Al diode have been improved with PEDOT-PSS conducting polymer

An HPLC Method for Microanalysis and Pharmacokinetics of Marine Sulfated Polysaccharide PSS-Loaded Poly Lactic-co-Glycolic Acid (PLGA Nanoparticles in Rat Plasma

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Hua-Shi Guan

2013-04-01

Full Text Available This study was aimed at developing a sensitive and selective HPLC method with postcolumn fluorescence derivatization for the detection of propylene glycol alginate sodium sulfate (PSS in rat plasma. Plasma samples were prepared by a simple and fast ultrafiltration method. PSS was extracted from rat plasma with d-glucuronic acid as internal standard. Isocratic chromatographic separation was performed on a TSKgel G2500 PWxL column with the mobile phase of 0.1 M sodium sulfate at a flow rate of 0.5 mL/min. Analyte detection was achieved by fluorescence detection (FLD at 250 nm (excitation and 435 nm (emission using guanidine hydrochloride as postcolumn derivatizing reagent in an alkaline medium at 120 °C. The calibration curve was linear over a concentration range of 1–500 μg/mL, and the lower limit of detection (LLOD was found to be 250 ng/mL. This validated method was applied successfully to the pharmacokinetic study of PSS and PSS-loaded poly lactic-co-glycolic acid (PLGA nanoparticles (PSS-NP in rat plasma after a single intravenous (PSS only and oral administration (PSS and PSS-NP. Significant differences in the main pharmacokinetic parameters of PSS and PSS-NP were observed. The relative bioavailability of PSS-NP was 190.10% compared with PSS which shows that PSS-NP can improve oral bioavailability.

Moving away from exhaustion: how core self-evaluations influence academic burnout.

Science.gov (United States)

Lian, Penghu; Sun, Yunfeng; Ji, Zhigang; Li, Hanzhong; Peng, Jiaxi

2014-01-01

Academic burnout refers to students who have low interest, lack of motivation, and tiredness in studying. Studies concerning how to prevent academic burnout are rare. The present study aimed to investigate the impact of core self-evaluations on the academic burnout of university students, and mainly focused on the confirmation of the mediator role of life satisfaction. A total of 470 university students accomplished the core self-evaluation scale, Satisfaction with Life, and academic burnout scale. Both core self-evaluations and life satisfaction were significantly correlated with academic burnout. Structural equation modeling indicated that life satisfaction partially mediated the relationship between core self-evaluations and academic burnout. Core self-evaluations significantly influence academic burnout and are partially mediated by life satisfaction.

Sheet resistance, transmittance, and chromatic property of CNTs coated with PEDOT:PSS films for transparent electrodes of touch screen panels

Energy Technology Data Exchange (ETDEWEB)

Kim, Bu-Jong; Han, Sang-Hoon; Park, Jin-Seok

2014-12-01

This study demonstrates hybrid-type transparent electrodes based on carbon nanotubes (CNTs) that possess characteristics desirable for touch screen panels. This has been accomplished by depositing CNTs via spray-coating and then depositing thin conductive polymer (such as PEDOT:PSS) films on the CNTs via spin-coating. For all of the samples such as CNTs, PEDOT:PSS, and hybrid (i.e., PEDOT:PSS-coated CNTs), their surface morphologies, sheet resistances, visible transmittances, and chromatic properties are characterized as functions of their preparation conditions. In the PEDOT:PSS-coated CNTs, the PEDOT:PSS particles fill up the voids between tubes in CNTs, forming a conduction bridge for electron transfer and eventually decreasing the sheet resistance of the hybrid electrode. Also, the hybrid electrode reveals a superior color property compared with that of CNTs or the PEDOT:PSS single electrode due to the complementary color relation between CNTs and PEDOT:PSS. Experimental results show that the fabricated hybrid-type electrodes can simultaneously satisfy the requirements necessary for transparent electrodes of touch screen panels such as the sheet resistance requiring to be lower than 100 Ω/sq, visible transmittance higher than 80%, and yellowness approaching to zero. - Highlights: • Hybrid-type (PEDOT:PSS-coated CNTs) electrodes for touch panels are fabricated. • PEDOT:PSS films are coated via spin-coating on spray-deposited CNTs. • Hybrid electrodes are fabricated by varying the thickness of CNTs and PEDOT:PSS. • The resistance, transmittance, and color properties have been analyzed. • Hybrid electrodes satisfy electrical and optical properties for touch panels.

Sheet resistance, transmittance, and chromatic property of CNTs coated with PEDOT:PSS films for transparent electrodes of touch screen panels

International Nuclear Information System (INIS)

Kim, Bu-Jong; Han, Sang-Hoon; Park, Jin-Seok

2014-01-01

This study demonstrates hybrid-type transparent electrodes based on carbon nanotubes (CNTs) that possess characteristics desirable for touch screen panels. This has been accomplished by depositing CNTs via spray-coating and then depositing thin conductive polymer (such as PEDOT:PSS) films on the CNTs via spin-coating. For all of the samples such as CNTs, PEDOT:PSS, and hybrid (i.e., PEDOT:PSS-coated CNTs), their surface morphologies, sheet resistances, visible transmittances, and chromatic properties are characterized as functions of their preparation conditions. In the PEDOT:PSS-coated CNTs, the PEDOT:PSS particles fill up the voids between tubes in CNTs, forming a conduction bridge for electron transfer and eventually decreasing the sheet resistance of the hybrid electrode. Also, the hybrid electrode reveals a superior color property compared with that of CNTs or the PEDOT:PSS single electrode due to the complementary color relation between CNTs and PEDOT:PSS. Experimental results show that the fabricated hybrid-type electrodes can simultaneously satisfy the requirements necessary for transparent electrodes of touch screen panels such as the sheet resistance requiring to be lower than 100 Ω/sq, visible transmittance higher than 80%, and yellowness approaching to zero. - Highlights: • Hybrid-type (PEDOT:PSS-coated CNTs) electrodes for touch panels are fabricated. • PEDOT:PSS films are coated via spin-coating on spray-deposited CNTs. • Hybrid electrodes are fabricated by varying the thickness of CNTs and PEDOT:PSS. • The resistance, transmittance, and color properties have been analyzed. • Hybrid electrodes satisfy electrical and optical properties for touch panels

Determining Factors for Stress Perception Assessed with the Perceived Stress Scale (PSS-4) in Spanish and Other European Samples.

Science.gov (United States)

Vallejo, Miguel A; Vallejo-Slocker, Laura; Fernández-Abascal, Enrique G; Mañanes, Guillermo

2018-01-01

Objective: Stress perception depends on cultural and social aspects that vary from one country to another. One of the most widely disseminated methods of assessing psychological stress is the Perceived Stress Scale (PSS-4). Therefore, in order to identify these factors and their impact on mental health, the present study compares the PSS-4 results among three European countries (Great Britain, France and Spain). This study focuses on PSS-4 results within a Spanish sample to determine: (1) normative data, reliability and validity of PSS-4 in a Spanish sample and (2) how stress perception changes depending on cultural and social factors. Methods: The data were obtained from a website representing a service of a smoking cessation program, the study represented a service that was open to all individuals. The number of participants were 37,451. They reported their age, gender, nationality, marital status, education and employment status, and completed two psychological questionnaires (PPS-4 and the anxiety and depression scales of the Symptom Checklist-90-Revised, SCL 90-R). Results: The PSS-4 scores could differentiate between relevant sociodemographic variables (such as sex, age, nationality, marital status, education, parental status, employment status, and income class). The PSS-4 scores showed a positive correlation with the SCL 90-R anxiety and depression scales. The normed values for interpreting the PSS-4 scores are presented. The PSS-4 showed adequate internal consistency and reliability. Conclusions: The PSS-4 is a useful instrument for assessing stress perception levels in the general population in different countries. Its internal consistency is sufficient for a 4-item scale.

Morphology, conductivity, and wetting characteristics of PEDOT:PSS thin films deposited by spin and spray coating

Energy Technology Data Exchange (ETDEWEB)

Zabihi, F.; Xie, Y.; Gao, S.; Eslamian, M., E-mail: Morteza.Eslamian@sjtu.edu.cn

2015-05-30

Highlights: • Nanostructure of spun-on and spray-on PEDOT:PSS thin films is studied. • A correlation is established between the film nanostructure and electrical conductivity. • Effect of process parameters is studied on the film characteristics. • A high solution concentration, high process temperature and multiple deposition layers are recommended. - Abstract: The goal of this paper is to study the characteristics of PEDOT:PSS thin films and the effects of varying the processing parameters on the structure, functionality, and surface wetting of spun-on and spray-on PEDOT:PSS thin films. PEDOT:PSS is a polymer mixture, which is electrically conductive and transparent and, therefore, is an attractive material for some optoelectronic applications, such as organic and perovskite solar cells. In this work, the films are fabricated using spin coating (a lab-scale method) and spray coating (an up-scalable method). The effects of spinning speed, drying time, and post-annealing temperature on spun-on samples and the effects of the substrate temperature and number of spray passes (deposition layers) on spray-on samples, as well as the effect of precursor solution concentration on both cases are investigated. Various characterization tools, such as AFM, SEM, XRD, confocal laser scanning microscopy (CLSM), and electrical conductivity measurements are used to determine the film roughness, thickness, structure, and morphology. The solution precursor physical data, such as contact angle on glass substrates, viscosity, and interfacial tension, are also obtained within a practical range of temperatures and concentrations. It is found that in both spin and spray coating routes, only well-controlled operating conditions result in the formation of conductive and defect-free PEDOT:PSS films. The formation of PEDOT:PSS thin films with small grains composed of PEDOT forming the core of the grains and PSS forming a shell or coating, which are evenly distributed in a PSS

Morphology, conductivity, and wetting characteristics of PEDOT:PSS thin films deposited by spin and spray coating

International Nuclear Information System (INIS)

Zabihi, F.; Xie, Y.; Gao, S.; Eslamian, M.

2015-01-01

Highlights: • Nanostructure of spun-on and spray-on PEDOT:PSS thin films is studied. • A correlation is established between the film nanostructure and electrical conductivity. • Effect of process parameters is studied on the film characteristics. • A high solution concentration, high process temperature and multiple deposition layers are recommended. - Abstract: The goal of this paper is to study the characteristics of PEDOT:PSS thin films and the effects of varying the processing parameters on the structure, functionality, and surface wetting of spun-on and spray-on PEDOT:PSS thin films. PEDOT:PSS is a polymer mixture, which is electrically conductive and transparent and, therefore, is an attractive material for some optoelectronic applications, such as organic and perovskite solar cells. In this work, the films are fabricated using spin coating (a lab-scale method) and spray coating (an up-scalable method). The effects of spinning speed, drying time, and post-annealing temperature on spun-on samples and the effects of the substrate temperature and number of spray passes (deposition layers) on spray-on samples, as well as the effect of precursor solution concentration on both cases are investigated. Various characterization tools, such as AFM, SEM, XRD, confocal laser scanning microscopy (CLSM), and electrical conductivity measurements are used to determine the film roughness, thickness, structure, and morphology. The solution precursor physical data, such as contact angle on glass substrates, viscosity, and interfacial tension, are also obtained within a practical range of temperatures and concentrations. It is found that in both spin and spray coating routes, only well-controlled operating conditions result in the formation of conductive and defect-free PEDOT:PSS films. The formation of PEDOT:PSS thin films with small grains composed of PEDOT forming the core of the grains and PSS forming a shell or coating, which are evenly distributed in a PSS

Results of RNV studies and /sup 201/Tl myocardial scintigraphy in patients with progressive systemic scleroderma (PSS)

Energy Technology Data Exchange (ETDEWEB)

Ammari, B.; Hotze, A.; Gruenwald, F.; Biersack, H.J.; Biltz, H.; Kuester, W.

1988-12-01

Prognosis of progressive systemic scleroderma (PSS) depends directly on the extent of visceral organ involvement, and in particular, on the cardiac, renal and pulmonary appearance. Therapeutic approaches therefore require periodic followup with non-invasive methods to evaluate the actual course of disease and the success of therapy. Tl-201 scintigraphy showed pathologic heart abnormalities in 47% and RNV in 23% of the PSS patients. Our results and published data reveal the sensitivity of both myocardial scans and RNV in the evaluation of patients with PSS. Other current methods for the diagnosis of heart diseases, however, such as echocardiography should also be performed. In patients with PSS coronary angiography, however, usually shows normal coronary vessels.

The Relative Age Effect and Its Influence on Academic Performance.

Science.gov (United States)

Navarro, Juan-José; García-Rubio, Javier; Olivares, Pedro R

2015-01-01

The policy of school organisation for grouping students in the same academic year is based on date of birth. The differences in the experiences and maturation of older students involve a relatively better performance in academic settings, which is known as the relative age effect (RAE). This effect is more important the younger the student is. The goal of this study is to identify the connections of influence that RAE, socioeconomic status (SES), and type of institution have on academic performance in a school population of eighth graders. The study is based on a population-based, representative sample of 15,234 8th graders (50.4% female; average age = 13.61 years) in the 2011 National System of Quality Assessment in Education Survey (SIMCE) from Chile. The SIMCE for global academic performance consists of 4 tests: reading, mathematics, social studies, and science. All tests consist of multiple-choice and closed questions. In addition, in order to have the information of general academic performance, an extra variable expressing the average score of each student was created. Also, the SIMCE includes additional variables for the evaluation process such as SES or type of school. Students were assigned to one of five age groups in terms of date of birth (G1, G2, G3, G4, and G5), in which students belonging to G1 are the oldest and students belonging to G5 are the youngest. The results achieved in the structural equation modelling indicate a good global fit. Individual relationships show significant effects of the three variables observed on academic performance, although SES received the highest values. The influence of RAE took place both in the full sample and sub-samples composed according to the SES and academic performance, showing higher values for students with lower scores. Although the influence of RAE decreases when SES is controlled, its effect is still significant and contributes to additionally explain the performance. The RAE remains, even with residual

The Relative Age Effect and Its Influence on Academic Performance.

Directory of Open Access Journals (Sweden)

Juan-José Navarro

Full Text Available The policy of school organisation for grouping students in the same academic year is based on date of birth. The differences in the experiences and maturation of older students involve a relatively better performance in academic settings, which is known as the relative age effect (RAE. This effect is more important the younger the student is. The goal of this study is to identify the connections of influence that RAE, socioeconomic status (SES, and type of institution have on academic performance in a school population of eighth graders.The study is based on a population-based, representative sample of 15,234 8th graders (50.4% female; average age = 13.61 years in the 2011 National System of Quality Assessment in Education Survey (SIMCE from Chile. The SIMCE for global academic performance consists of 4 tests: reading, mathematics, social studies, and science. All tests consist of multiple-choice and closed questions. In addition, in order to have the information of general academic performance, an extra variable expressing the average score of each student was created. Also, the SIMCE includes additional variables for the evaluation process such as SES or type of school. Students were assigned to one of five age groups in terms of date of birth (G1, G2, G3, G4, and G5, in which students belonging to G1 are the oldest and students belonging to G5 are the youngest.The results achieved in the structural equation modelling indicate a good global fit. Individual relationships show significant effects of the three variables observed on academic performance, although SES received the highest values. The influence of RAE took place both in the full sample and sub-samples composed according to the SES and academic performance, showing higher values for students with lower scores. Although the influence of RAE decreases when SES is controlled, its effect is still significant and contributes to additionally explain the performance.The RAE remains, even

Moving Away from Exhaustion: How Core Self-Evaluations Influence Academic Burnout

Science.gov (United States)

Lian, Penghu; Sun, Yunfeng; Ji, Zhigang; Li, Hanzhong; Peng, Jiaxi

2014-01-01

Background Academic burnout refers to students who have low interest, lack of motivation, and tiredness in studying. Studies concerning how to prevent academic burnout are rare. Objective The present study aimed to investigate the impact of core self-evaluations on the academic burnout of university students, and mainly focused on the confirmation of the mediator role of life satisfaction. Methods A total of 470 university students accomplished the core self-evaluation scale, Satisfaction with Life, and academic burnout scale. Results Both core self-evaluations and life satisfaction were significantly correlated with academic burnout. Structural equation modeling indicated that life satisfaction partially mediated the relationship between core self-evaluations and academic burnout. Conclusions Core self-evaluations significantly influence academic burnout and are partially mediated by life satisfaction. PMID:24489857

Moving away from exhaustion: how core self-evaluations influence academic burnout.

Directory of Open Access Journals (Sweden)

Penghu Lian

Full Text Available BACKGROUND: Academic burnout refers to students who have low interest, lack of motivation, and tiredness in studying. Studies concerning how to prevent academic burnout are rare. OBJECTIVE: The present study aimed to investigate the impact of core self-evaluations on the academic burnout of university students, and mainly focused on the confirmation of the mediator role of life satisfaction. METHODS: A total of 470 university students accomplished the core self-evaluation scale, Satisfaction with Life, and academic burnout scale. RESULTS: Both core self-evaluations and life satisfaction were significantly correlated with academic burnout. Structural equation modeling indicated that life satisfaction partially mediated the relationship between core self-evaluations and academic burnout. CONCLUSIONS: Core self-evaluations significantly influence academic burnout and are partially mediated by life satisfaction.

Determining Factors for Stress Perception Assessed with the Perceived Stress Scale (PSS-4 in Spanish and Other European Samples

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Miguel A. Vallejo

2018-01-01

Full Text Available Objective: Stress perception depends on cultural and social aspects that vary from one country to another. One of the most widely disseminated methods of assessing psychological stress is the Perceived Stress Scale (PSS-4. Therefore, in order to identify these factors and their impact on mental health, the present study compares the PSS-4 results among three European countries (Great Britain, France and Spain. This study focuses on PSS-4 results within a Spanish sample to determine: (1 normative data, reliability and validity of PSS-4 in a Spanish sample and (2 how stress perception changes depending on cultural and social factors.Methods: The data were obtained from a website representing a service of a smoking cessation program, the study represented a service that was open to all individuals. The number of participants were 37,451. They reported their age, gender, nationality, marital status, education and employment status, and completed two psychological questionnaires (PPS-4 and the anxiety and depression scales of the Symptom Checklist-90-Revised, SCL 90-R.Results: The PSS-4 scores could differentiate between relevant sociodemographic variables (such as sex, age, nationality, marital status, education, parental status, employment status, and income class. The PSS-4 scores showed a positive correlation with the SCL 90-R anxiety and depression scales. The normed values for interpreting the PSS-4 scores are presented. The PSS-4 showed adequate internal consistency and reliability.Conclusions: The PSS-4 is a useful instrument for assessing stress perception levels in the general population in different countries. Its internal consistency is sufficient for a 4-item scale.

The Thai version of the PSS-10: An Investigation of its psychometric properties

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Wongpakaran Tinakon

2010-06-01

Full Text Available Abstract Background Among the stress instruments that measure the degree to which life events are perceived as stressful, the Perceived Stress Scale (PSS is widely used. The goal of this study was to examine the psychometric properties of a Thai version of the PSS-10 (T-PSS-10 with a clinical and non-clinical sample. Internal consistency, test-retest reliability, concurrent validity, and the factorial structure of the scale were tested. Methods A total sample of 479 adult participants was recruited for the study: 368 medical students and 111 patients from two hospitals in Northern Thailand. The T-PSS-10 was used along with the Thai version of State Trait Anxiety Inventory (STAI, the Thai Version of the Rosenberg Self-Esteem Scale (RSES, and the Thai Depression Inventory (TDI. Results Exploratory Factor Analysis (EFA yielded 2 factors with eigenvalues of 5.05 and 1.60, accounting for 66 percent of variance. Factor 1 consisted of 6 items representing "stress"; whereas Factor 2 consisted of 4 items representing "control". The item loadings ranged from 0.547 to 0.881. Investigation of the fit indices associated with Maximum Likelihood (ML estimation revealed that the two-factor solution was adequate [χ2 = 35.035 (df = 26, N = 368, p r = 0.60, p r = 0.55, p r = -0.46, p Conclusions The Thai version of the PSS-10 demonstrated excellent goodness-of-fit for the two factor solution model, as well as good reliability and validity for estimating the level of stress perception with a Thai population. Limitations of the study are discussed.

Association of academic stress with sleeping difficulties in medical students of a Pakistani medical school: a cross sectional survey

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Ahmed Waqas

2015-03-01

Full Text Available Introduction. Medicine is one of the most stressful fields of education because of its highly demanding professional and academic requirements. Psychological stress, anxiety, depression and sleep disturbances are highly prevalent in medical students.Methods. This cross-sectional study was undertaken at the Combined Military Hospital Lahore Medical College and the Institute of Dentistry in Lahore (CMH LMC, Pakistan. Students enrolled in all yearly courses for the Bachelor of Medicine and Bachelor of Surgery (MBBS degree were included. The questionnaire consisted of four sections: (1 demographics (2 a table listing 34 potential stressors, (3 the 14-item Perceived Stress Scale (PSS-14, and (4 the Pittsburgh Quality of Sleep Index (PSQI. Logistic regression was run to identify associations between group of stressors, gender, year of study, student’s background, stress and quality of sleep.Results. Total response rate was 93.9% (263/280 respondents returned the questionnaire. The mean (SD PSS-14 score was 30 (6.97. Logistic regression analysis showed that cases of high-level stress were associated with year of study and academic-related stressors only. Univariate analysis identified 157 cases with high stress levels (59.7%. The mean (SD PSQI score was 8.1 (3.12. According to PSQI score, 203/263 respondents (77% were poor sleepers. Logistic regression showed that mean PSS-14 score was a significant predictor of PSQI score (OR 1.99, P < 0.05.Conclusion. We found a very high prevalence of academic stress and poor sleep quality among medical students. Many medical students reported using sedatives more than once a week. Academic stressors contributed significantly to stress and sleep disorders in medical students.

Correlation between the fine structure of spin-coated PEDOT:PSS and the photovoltaic performance of organic/crystalline-silicon heterojunction solar cells

Energy Technology Data Exchange (ETDEWEB)

Funda, Shuji; Ohki, Tatsuya; Liu, Qiming; Hossain, Jaker; Ishimaru, Yoshihiro; Ueno, Keiji; Shirai, Hajime [Graduate School of Science and Engineering, Saitama University, Saitama 338-8570 (Japan)

2016-07-21

We investigated the relationship between the fine structure of spin-coated conductive polymer poly(3,4-ethylenedioxythiphene):poly(styrene sulfonate) (PEDOT:PSS) films and the photovoltaic performance of PEDOT:PSS crystalline-Si (PEDOT:PSS/c-Si) heterojunction solar cells. Real-time spectroscopic ellipsometry revealed that there were two different time constants for the formation of the PEDOT:PSS network. Upon removal of the polar solvent, the PEDOT:PSS film became optically anisotropic, indicating a conformational change in the PEDOT and PSS chain. Polarized Fourier transform infrared attenuated total reflection absorption spectroscopy and Raman spectroscopy measurements also indicated that thermal annealing promoted an in-plane π-conjugated C{sub α} = C{sub β} configuration attributed to a thiophene ring in PEDOT and an out-of-plane configuration of -SO{sub 3} groups in the PSS chain with increasing composition ratio of oxidized (benzoid) to neutral (quinoid) PEDOT, I{sub qui}/I{sub ben}. The highest power conversion efficiency for the spin-coated PEDOT:PSS/c-Si heterojunction solar cells was 13.3% for I{sub qui}/I{sub ben} = 9–10 without employing any light harvesting methods.

Supporting the Development of Environmentally Sustainable PSS by Means of the Ecodesign Maturity Model

DEFF Research Database (Denmark)

Pigosso, Daniela Cristina Antelmi; McAloone, Tim C.

2015-01-01

best practice for ecodesign implementation and management. The Ecodesign Maturity Model (EcoM2) is a management framework that supports manufacturing companies to consistently and systematicallyimplement ecodesign, based on a step-by-step approach. EcoM2 contains a database containing more than 600...... practices, categorized into management practices, operational practices and methods &tools. Currently, only two management practices of theEcoM2address PSS development. This paper aims to identify the best practices for PSS development, based on a literature review, followed by a presentation of a proposal......Despite their substantial potential for enabling increased environmental performance, product/service-systems (PSS) are not intrinsically environmentally sustainable. In order to ensure increased sustainability performance, PSSand related business models needs to be developed taking into account...

Modification of the Highly Conductive PEDOT:PSS Layer for Use in Silver Nanogrid Electrodes for Flexible Inverted Polymer Solar Cells.

Science.gov (United States)

Wang, Jie; Fei, Fei; Luo, Qun; Nie, Shuhong; Wu, Na; Chen, Xiaolian; Su, Wenming; Li, Yuanjie; Ma, Chang-Qi

2017-03-01

Silver nanogrid based flexible transparent electrode is recognized as the most promising alternative to ITO electrode for organic electronics, owing to its low production cost and excellent flexibility. Typically, a highly conductive thin film coating layer, such as highly conductive PEDOT:PSS (HC-PEDOT:PSS) is usually deposited onto the Ag-grid electrode to smooth the surface and to minimize the sheet resistance. In this paper, we found that inverted flexible polymer solar cells with structure of Ag-grid/HC-PEDOT:PSS/ZnO/photoactive layer/MoO 3 /Al generally exhibits strong S-shaped J-V curves, which could be eliminated by light-soaking treatment. Kelvin probe force microscope (KPFM) measurement proved that a large work function (WF) difference (0.70 eV) between HC-PEDOT:PSS and ZnO is the main reason for the formation of S-shape. White light soaking of the Ag-grid/HC-PEDOT:PSS gradually decreased the WF of HC-PEDOT:PSS from 5.10 to 4.60 eV, leading to a reduced WF difference between HC-PEDOT:PSS and ZnO from 0.70 to 0.38 eV. Such a WF difference decrease was believed to be the working mechanism for the light-soaking effect in this flexible device. Based on this finding, the HC-PEDOT:PSS solution was then modified by doping with polyethylenimine (PEI) and aqueous ammonia. The modified PEDOT:PSS film is characteristic of adjusting WF through varying PEI doping concentrations. By using such a modified PEDOT:PSS layer, light-soaking-free flexible inverted polymer solar cell with a power conversion efficiency of 6.58% was achieved for PTB7-Th:PC 71 BM cells. The current work provides a useful guideline for interfacial modification for Ag-grid based flexible electrode.

A Survey of the Influencing Factors for International Academic Mobility of Chinese University Students

Science.gov (United States)

Cao, Chun; Zhu, Chang; Meng, Qian

2016-01-01

This research aims to understand the factors influencing international academic mobility within the Chinese higher education context. The inventory of University Students' Perceptions of Influencing Factors for International Academic Mobility was developed and tested to enquire about Chinese university students' perceptions of factors influencing…

Multiwall carbon nanotube and poly(3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT:PSS) composite films for transistor and inverter devices.

Science.gov (United States)

Yun, Dong-Jin; Hong, KiPyo; Kim, Se hyun; Yun, Won-Min; Jang, Jae-young; Kwon, Woo-Sung; Park, Chan-Eon; Rhee, Shi-Woo

2011-01-01

Highly conductive multiwalled carbon nanotube (MWNT)/Poly(3,4-ethylenedioxythiophene) polymerized with poly(4-styrenesulfonate) (PEDOT:PSS) films were prepared by spin coating a mixture solution. The solution was prepared by dispersing MWNT in the PEDOT:PSS solution in water using ultrasonication without any oxidation process. The effect of the MWNT loading in the solution on the film properties such as surface roughness, work function, surface energy, optical transparency, and conductivity was studied. The conductivity of MWNT/PEDOT:PSS composite film was increased with higher MWNT loading and the high conductivity of MWNT/PEDOT:PSS films enabled them to be used as a source/drain electrode in organic thin film transistor (OTFT). The pentacene TFT with MWNT/PEDOT:PSS S/D electrode showed much higher performance with mobility about 0.2 cm²/(V s) and on/off ratio about 5 × 10⁵ compared to that with PEDOT:PSS S/D electrode (∼0.05 cm²/(V s), 1 × 10⁵). The complementary inverters exhibited excellent characteristics, including high gain value of about 30.

Influence of Facebook in Academic Performance of Sri Lankan University Students

OpenAIRE

Thuseethan, S.; Kuhanesan, S.

2015-01-01

Facebook is only an electronic communication between human but unfortunately it has become an addiction for all. This paper examines the usage of Facebook among university students and its influence in their academic performance. The impact of Facebook can either be good or bad on university students and in their academic activities. Even though a closer look on the real impact of Facebook reveals that it leads to several problems in university students academic performances. Today Facebook i...

Assessment of academic/non-academic factors and extracurricular activities influencing performance of medical students of faculty of medicine, Universiti Sultan Zainal Abidin, Malaysia

OpenAIRE

Mainul Haque; Nor Azlina A Rahman; Md. Anwarul Azim Majumder; Nor Iza A Rahman; Seraj Zohurul Haque; Zainal Zulkifli; Halyna Lugova; Rabiu Muazu Musa; Ahmed Ghazi Alattraqchi

2018-01-01

Background: Physical and mental comfort is known to have a crucial influence on health and performance amongst medical students. Very often, medical students suffer from poor quality of life (QOL) related to the work-life balance due to the lack of sleep, nutritional and dietary disorders and low physical activity, resulting in a negative impact on their academic performance. This study aims to determine the potential academic/non-academic factors and extra-curricular activities influencing t...

Influence of motivation on academic library employees' performance ...

African Journals Online (AJOL)

Influence of motivation on academic library employees' performance and productivity in ... Information Impact: Journal of Information and Knowledge Management ... motivated from time to time to boost their morale for efficiency and higher productivity. ... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL ...

Influences on Academic Achievement of Primary School Pupils in Cambodia

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Sopheak Song

2012-12-01

Full Text Available Employing education production function approach, this article investigates the influences of school and pupil background factors on academic achievement of primary school pupils in Cambodia. Based on achievement data of 1,080 Grade 6 pupils from one rural and one semi-urban area, the study reveals that school and teacher quality exerts a considerable effect on pupils’ performance. Teachers’ experience and teacher guides are positively correlated with academic achievement, while instructional time loss is significantly associated with poor performance. In light of these results, policies to boost academic achievement of primary school pupils in Cambodia are discussed.

Solution synthesis of telluride-based nano-barbell structures coated with PEDOT:PSS for spray-printed thermoelectric generators

Science.gov (United States)

Bae, Eun Jin; Kang, Young Hun; Jang, Kwang-Suk; Lee, Changjin; Cho, Song Yun

2016-05-01

Solution-processable telluride-based heterostructures coated with poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (Te-Bi2Te3/PEDOT:PSS) were synthesized through a solution-phase reaction at low temperatures. The water-based synthesis yielded PEDOT:PSS-coated Te-Bi2Te3 nano-barbell structures with a high Seebeck coefficient that can be stably dispersed in water. These hybrid solutions were deposited onto a substrate by the spray-printing method to prepare thermoelectric generators. The thermoelectric properties of the Te-Bi2Te3/PEDOT:PSS hybrid films were significantly enhanced by a simple acid treatment due to the increased electrical conductivity, and the power factor of those materials can be effectively tuned over a wide range depending on the acid concentration of the treatment. The power factors of the synthesized Te-Bi2Te3/PEDOT:PSS hybrids were optimized to 60.05 μW m-1 K-2 with a Seebeck coefficient of 93.63 μV K-1 and an electrical conductivity of 69.99 S cm-1. The flexible thermoelectric generator fabricated by spray-printing Te-Bi2Te3/PEDOT:PSS hybrid solutions showed an open-circuit voltage of 1.54 mV with six legs at ΔT = 10 °C. This approach presents the potential for realizing printing-processable hybrid thermoelectric materials for application in flexible thermoelectric generators.Solution-processable telluride-based heterostructures coated with poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (Te-Bi2Te3/PEDOT:PSS) were synthesized through a solution-phase reaction at low temperatures. The water-based synthesis yielded PEDOT:PSS-coated Te-Bi2Te3 nano-barbell structures with a high Seebeck coefficient that can be stably dispersed in water. These hybrid solutions were deposited onto a substrate by the spray-printing method to prepare thermoelectric generators. The thermoelectric properties of the Te-Bi2Te3/PEDOT:PSS hybrid films were significantly enhanced by a simple acid treatment due to the increased electrical conductivity, and

Large area ITO-free flexible white OLEDs with Orgacon™ PEDOT:PSS and printed metal shunting lines

NARCIS (Netherlands)

Harkema, S.; Mennema, S.; Barink, M.; Rooms, H.C.A.; Wilsona, J.S.; Mol, A.M.B. van; Bollen, D.

2009-01-01

We demonstrate the feasibility of white organic light-emitting diodes that exclude the transparent conductor indium-tinoxide. Instead, a highly conductive Orgacon™ PEDOT:PSS material in combination with a metal support structure is used as transparent anode and hole-injection layer. The PEDOT:PSS

Business-IT alignment in PSS value networks linking customer knowledge management to social customer relationship management

NARCIS (Netherlands)

Bagheri, S.; Kusters, R.J.; Trienekens, J.J.M.; Hammoudi, S.; Cordeiro, J.; Maciaszek, L.

2015-01-01

Offering a PSS that is based on co-creating value with customer, starts with understanding customer needs. Customer understanding is realized through the process of managing customer knowledge across a PSS value network. In this respect, customer knowledge management (CKM) is seen as a core business

PEDOT:PSS incorporated silver nanoparticles prepared by gamma radiation for the application in organic solar cells

Directory of Open Access Journals (Sweden)

Omayma A. Ghazy

2015-04-01

Full Text Available Poly(3,4-ethylenedioxythiophene:Polystyrene sulfonate (PEDOT:PSS is a dispersion used as a buffer layer on the ITO electrode in the organic solar cells. Silver nanoparticles (Ag NPs are incorporated to the dispersion using two different strategies. The first is by reduction of silver ions in the PEDOT:PSS dispersion. Chemical reduction of silver ions using sodium borohydried is compared with reduction using gamma radiation. The TEM and UV-visible spectra indicates that smaller Ag NPs are obtained for the chemical reduction method than those obtained from the radiochemical. The second strategy, is by preparing Ag NPs in polyvinyl pyrolidone (PVP solution using gamma irradiation then adding them to the PEDOT:PSS dispersion. Layers of the PEDOT:PSS incorporated different concentrations of Ag NPs (1, 2, 4, 6, 8, 10% are formed. The SEM and AFM studies of the layers morphology reveal that smooth morphology on the obtained for layers containing Ag NPs up to concentrations of 4%.

P-doped organic semiconductor: Potential replacement for PEDOT:PSS in organic photodetectors

Energy Technology Data Exchange (ETDEWEB)

Herrbach, J.; Revaux, A., E-mail: amelie.revaux@cea.fr [University of Grenoble Alpes, CEA-LITEN, Grenoble 38000 (France); Vuillaume, D. [IEMN, CNRS, University of Lille, Villeneuve d' Ascq 59652 (France); Kahn, A. [Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544 (United States)

2016-08-15

In this work, we present an alternative to the use of PEDOT:PSS as hole transport and electron blocking layers in organic photodetectors processed by solution. As Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) is known to be sensitive to humidity, oxygen, and UV, removing this layer is essential for lifetime improvements. As a first step to achieving this goal, we need to find an alternative layer that fulfills the same role in order to obtain a working diode with similar or better performance. As a replacement, a layer of poly[(4,8-bis-(2-ethylhexyloxy)-benzo(1,2-b:4,5-b′)dithiophene)-2, 6-diyl-alt-(4-(2-ethylhexanoyl)-thieno[3,4-b]thiophene-)-2-6-diyl)] (PBDTTT-c) p-doped with the dopant tris-[1-(trifluoroethanoyl)-2-(trifluoromethyl)ethane-1,2-dithiolene] (Mo(tfd-COCF{sub 3}){sub 3}) is used. This p-doped layer effectively lowers the hole injection barrier, and the low electron affinity of the polymer prevents the injection of electrons into the active layer. We show similar device performance under light and the improvements of detection performance with the doped layer in comparison with PEDOT:PSS, leading to a detectivity of 1.9 × 10{sup 13} cm (Hz){sup 1/2} (W){sup −1}, competitive with silicon diodes used in imaging applications. Moreover, contrary to PEDOT:PSS, no localization of the p-doped layer is needed, leading to a diode active area defined by the patterned electrodes.

High Performance of PEDOT:PSS/n-Si Solar Cells Based on Textured Surface with AgNWs Electrodes

Science.gov (United States)

Jiang, Xiangyu; Zhang, Pengbo; Zhang, Juan; Wang, Jilei; Li, Gaofei; Fang, Xiaohong; Yang, Liyou; Chen, Xiaoyuan

2018-02-01

Hybrid heterojunction solar cells (HHSCs) have gained extensive research and attention due to simple device structure and low-cost technological processes. Here, HHSCs are presented based on a highly transparent conductive polymer poly(3,4ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS) directly spin-coated on an n-type crystalline silicon with microscale surface textures, which are prepared by traditional chemical etching. We have studied interface properties between PEDOT:PSS and textured n-Si by varying coating conditions. Final power conversion efficiency (PCE) could arrive at 8.54% by these simple solution-based fabrication processes. The high conversion efficiency is attributed to the fully conformal contact between PEDOT:PSS film and textured silicon. Furthermore, the reflectance of the PEDOT:PSS layer on textured surface is analyzed by changing film thickness. In order to improve the performance of the device, silver nanowires were employed as electrodes because of its better optical transmittance and electrical conductivity. The highest PCE of 11.07% was achieved which displayed a 29.6% enhancement compared with traditional silver electrodes. These findings imply that the combination of PEDOT:PSS film and silver nanowire transparent electrodes pave a promising way for realizing high-efficiency and low-cost solar cells.

Limitations on Change: Current Conditions Influencing Academic Intransigence in Educational Administration Programs.

Science.gov (United States)

Logan, Connie Stokes; Pounder, Diana G.

An analysis of academic intransigence (resistance to change) in educational administrative preparation programs is presented in this paper. Drawing upon two conceptual frameworks, the stakeholder perspective and Porter's (1980) five-force model of industry structure and competitive influence, two factors contributing to academic intransigence are…

PSS and TCSC damping controller coordinated design using PSO in multi-machine power system

Energy Technology Data Exchange (ETDEWEB)

Shayeghi, H., E-mail: hshayeghi@gmail.co [Technical Engineering Department, University of Mohaghegh Ardabili, Ardabil (Iran, Islamic Republic of); Safari, A.; Shayanfar, H.A. [Center of Excellence for Power System Automation and Operation, Electrical Engineering Department, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of)

2010-12-15

The paper develops a new design procedure for simultaneous coordinated designing of the thyristor controlled series capacitor (TCSC) damping controller and power system stabilizer (PSS) in multi-machine power system. The coordinated design problem of PSS and TCSC damping controllers over a wide range of loading conditions is converted to an optimization problem with the time domain-based objective function that is solved by a particle swarm optimization (PSO) technique which has a strong ability to find the most optimistic results. By minimizing the proposed fitness function in which oscillatory characteristics between areas are included and thus the interactions among the TCSC controller and PSS under transient conditions in the multi-machine power system are improved. To ensure the robustness of the proposed stabilizers, the design process takes a wide range of operating conditions into account. The effectiveness of the proposed controller is demonstrated through the nonlinear time-domain simulation and some performance indices studies. The results of these studies show that the proposed coordinated controllers have an excellent capability in damping power system inter-area oscillations and enhance greatly the dynamic stability of the power system. Moreover, it is superior to both the uncoordinated designed stabilizers of the PSS and the TCSC damping controller.

Economical low-light photovoltaics by using the Pt-free dye-sensitized solar cell with graphene dot/PEDOT:PSS counter electrodes

KAUST Repository

Lee, Chuan Pei

2015-10-23

Graphene dots (GDs) are used for enhancing the performance of the poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS)-based counter electrodes in Pt-free dye-sensitized solar cells (DSSCs). As compared to PEDOT:PSS CEs, GD-PEDOT:PSS films possess a rough surface morphology, high conductivity and electrocatalytic activity, and low charge-transfer resistance toward I/I redox reaction, pushing cell efficiency to 7.36%, which is 43% higher than that of the cell with PEDOT:PSS CEs (5.14%). Without much impact on efficiency, the DSSCs with GD-PEDOT:PSS CEs work well under low-light conditions (light intensity <13.5mWcm and angle of incidence >60°), such as indoor and low-level outdoor lighting and of the sun while the other traditional cells would fail to work. The concurrent advantage in low cost in Pt-free materials, simple fabrication processes, comparable efficiency with Pt CEs, and high performance under low-light conditions makes the DSSC with GD-PEDOT:PSS CEs suitable to harvest light for a diverse range of indoor and low-level outdoor lighting locations.

The Influence of Selected Personality and Workplace Features on Burnout among Nurse Academics

Science.gov (United States)

Kizilci, Sevgi; Erdogan, Vesile; Sozen, Emine

2012-01-01

This study aimed to determine the influence of selected individual and situational features on burnout among nurse academics. The Maslach Burnout Inventory was used to assess the burnout levels of academics. The sample population comprised 94 female participant. The emotion exhaustion (EE) score of the nurse academics was 16.43[plus or minus]5.97,…

Preparation of graphene oxide/poly (3,4-ethylenedioxytriophene): Poly (styrene sulfonate) (PEDOT:PSS) electrospun nanofibers

International Nuclear Information System (INIS)

Efelina, Vita; Widianto, Eri; Rusdiana, Dadi; Nugroho, A. A.; Kusumaatmaja, Ahmad; Triyana, Kuwat; Santoso, Iman

2016-01-01

Graphene oxide (GO)/Poly (3,4-Ethylenedioxytriophene):Poly (styrene Sulfonate) (PEDOT:PSS) nanofibers have been successfully fabricated by a simple electrospinning technique to develop conductive nanofibers with polyvinyl alcohol (PVA) act as a carrier solution. Graphene oxide has been synthesized by Hummer’s method and has been confirmed by Raman Spectroscopy, FTIR and UV-Vis Spectroscopy. GO/PEDOT:PSS composite nanofibers. The structural and morphological properties were characterized by Scanning Electron Microscopy (SEM). The result of SEM show that GO/PEDOT:PSS nanofibers has a relatively uniform morphology nanofiber with diameter between 180 nm - 340 nm with smooth nanofiber surface. The produced nanofibers from this study can be utilized for various applications such as flexible, conductive and transparent electrode.

Preparation of graphene oxide/poly (3,4-ethylenedioxytriophene): Poly (styrene sulfonate) (PEDOT:PSS) electrospun nanofibers

Energy Technology Data Exchange (ETDEWEB)

Efelina, Vita; Widianto, Eri [Department of Physics, Universitas Gadjah Mada, Sekip Utara BLS.21 Yogyakarta, 55281 Indonesia (Indonesia); Rusdiana, Dadi [Department of Physical Education, Universitas Pendidikan Indonesia, Bandung (Indonesia); Nugroho, A. A. [Department of Physics, Institut Teknologi Bandung, Jl. Ganesha 10 Bandung (Indonesia); Kusumaatmaja, Ahmad; Triyana, Kuwat; Santoso, Iman, E-mail: iman.santoso@ugm.ac.id [Department of Physics, Universitas Gadjah Mada, Sekip Utara BLS.21 Yogyakarta, 55281 Indonesia (Indonesia); Nanomaterials Research Group, Universitas Gadjah Mada,, Sekip Utara, Yogyakarta (Indonesia)

2016-04-19

Graphene oxide (GO)/Poly (3,4-Ethylenedioxytriophene):Poly (styrene Sulfonate) (PEDOT:PSS) nanofibers have been successfully fabricated by a simple electrospinning technique to develop conductive nanofibers with polyvinyl alcohol (PVA) act as a carrier solution. Graphene oxide has been synthesized by Hummer’s method and has been confirmed by Raman Spectroscopy, FTIR and UV-Vis Spectroscopy. GO/PEDOT:PSS composite nanofibers. The structural and morphological properties were characterized by Scanning Electron Microscopy (SEM). The result of SEM show that GO/PEDOT:PSS nanofibers has a relatively uniform morphology nanofiber with diameter between 180 nm - 340 nm with smooth nanofiber surface. The produced nanofibers from this study can be utilized for various applications such as flexible, conductive and transparent electrode.

In Situ Complementary Doping, Thermoelectric Improvements, and Strain-Induced Structure within Alternating PEDOT:PSS/PANI Layers.

Science.gov (United States)

Andrei, Virgil; Bethke, Kevin; Madzharova, Fani; Bronneberg, Aafke Cecile; Kneipp, Janina; Rademann, Klaus

2017-09-27

Although the deposition of alternating layers from poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and polyaniline (PANI) salts has recently provided a breakthrough in the field of conductive polymers, the cause for the conductivity improvement has remained unclear. In this work, we report a cooperative doping effect between alternating PANI base and PEDOT:PSS layers, resulting in electrical conductivities of 50-100 S cm -1 and power factors of up to 3.0 ± 0.5 μW m -1 K -2 , which surpass some of the recent values obtained for protonated PANI/PEDOT:PSS multilayers by a factor of 20. In this case, the simultaneous improvement in the electrical conductivity of both types of layers is caused by the in situ protonation of PANI, which corresponds to the removal of the excess acidic PSS chains from the PEDOT:PSS grains. The interplay between the functional groups' reactivity and the supramolecular chain reorganization leads to an array of preparation-dependent phenomena, including a stepwise increase in the film thickness, an alternation in the electrical conductivity, and the formation of a diverse surface landscape. The latter effect can be traced to a buildup of strain within the layers, which results in either the formation of folds or the shrinkage of the film. These results open new paths for designing nanostructured thin-film thermoelectrics.

Silicon surface passivation by PEDOT: PSS functionalized by SnO2 and TiO2 nanoparticles.

Science.gov (United States)

García-Tecedor, M; Karazhanov, S Zh; Vásquez, G C; Haug, H; Maestre, D; Cremades, A; Taeño, M; Ramírez-Castellanos, J; González-Calbet, J M; Piqueras, J; You, C C; Marstein, E S

2018-01-19

In this paper, we present a study of silicon surface passivation based on the use of spin-coated hybrid composite layers. We investigate both undoped poly(3,4-ethylenedioxythiophene)/poly-(styrenesulfonate) (PEDOT:PSS), as well as PEDOT:PSS functionalized with semiconducting oxide nanomaterials (TiO 2 and SnO 2 ). The hybrid compound was deposited at room temperature by spin coating-a potentially lower cost, lower processing time and higher throughput alternative compared with the commonly used vacuum-based techniques. Photoluminescence imaging was used to characterize the electronic properties of the Si/PEDOT:PSS interface. Good surface passivation was achieved by PEDOT:PSS functionalized by semiconducting oxides. We show that control of the concentration of semiconducting oxide nanoparticles in the polymer is crucial in determining the passivation performance. A charge carrier lifetime of about 275 μs has been achieved when using SnO 2 nanoparticles at a concentration of 0.5 wt.% as a filler in the composite film. X-ray diffraction (XRD), scanning electron microscopy, high resolution transmission electron microscopy (HRTEM), energy dispersive x-ray in an SEM, and μ-Raman spectroscopy have been used for the morphological, chemical and structural characterization. Finally, a simple model of a photovoltaic device based on PEDOT:PSS functionalized with semiconducting oxide nanoparticles has been fabricated and electrically characterized.

Enhanced photoelectrochemical performance of inorganic–organic hybrid consisting of BiVO{sub 4} and PEDOT:PSS

Energy Technology Data Exchange (ETDEWEB)

Trzciński, K. [Faculty of Chemistry, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk (Poland); Szkoda, M., E-mail: mariusz-szkoda@wp.pl [Faculty of Chemistry, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk (Poland); Siuzdak, K.; Sawczak, M. [Centre for Plasma and Laser Engineering, The Szewalski Institute of Fluid Flow Machinery, Fiszera 14, 80-231 Gdańsk (Poland); Lisowska-Oleksiak, A., E-mail: alo@pg.gda.pl [Faculty of Chemistry, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk (Poland)

2016-12-01

Highlights: • Bismuth vanadate layers were prepared using pulsed laser deposition technique. • The modification method of BiVO{sub 4} by PEDOT:PSS was developed. • Modified layers exhibited higher photoactivity than bare BiVO{sub 4}. • Prepared material can act as semiconducting layer in photoelectrochemical cells. - Abstract: The PEDOT:PSS (poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)) was electrodeposited on a thin layer of bismuth vanadate (BiVO{sub 4}) prepared using the pulsed laser deposition technique onto FTO. The inorganic–organic junction was characterized by Raman spectroscopy, UV–vis spectroscopy and scanning electron microscopy. Chronoamperometry curves, recorded under simulated solar light illumination, were performed to determine generated photocurrent during water and hydroquinone oxidation at the electrode surface. Experiments were performed for three types of electrode materials: (i) FTO/BiVO{sub 4}, (ii) FTO/PEDOT:PSS and (iii) FTO/BiVO{sub 4}/PEDOT:PSS in aqueous electrolyte. Almost 5 times higher photocurrent in electrolyte containing hole scavenger was generated after modification of BiVO{sub 4} photoanode with electrodeposited polymer. It is noteworthy that anodic photocurrent was stable even after 4 h of illumination. Cyclic voltammetry curves of FTO/BiVO{sub 4}/PEDOT:PSS recorded before and after experiments performed under electrode illumination indicated that the organic part in tested junction is photo-corrosion resistant.

Recognizing Academic Performance, Sleep Quality, Stress Level, and Mental Health using Personality Traits, Wearable Sensors and Mobile Phones.

Science.gov (United States)

Sano, Akane; Phillips, Andrew J; Yu, Amy Z; McHill, Andrew W; Taylor, Sara; Jaques, Natasha; Czeisler, Charles A; Klerman, Elizabeth B; Picard, Rosalind W

2015-06-01

What can wearable sensors and usage of smart phones tell us about academic performance, self-reported sleep quality, stress and mental health condition? To answer this question, we collected extensive subjective and objective data using mobile phones, surveys, and wearable sensors worn day and night from 66 participants, for 30 days each, totaling 1,980 days of data. We analyzed daily and monthly behavioral and physiological patterns and identified factors that affect academic performance (GPA), Pittsburg Sleep Quality Index (PSQI) score, perceived stress scale (PSS), and mental health composite score (MCS) from SF-12, using these month-long data. We also examined how accurately the collected data classified the participants into groups of high/low GPA, good/poor sleep quality, high/low self-reported stress, high/low MCS using feature selection and machine learning techniques. We found associations among PSQI, PSS, MCS, and GPA and personality types. Classification accuracies using the objective data from wearable sensors and mobile phones ranged from 67-92%.

The kinesin AtPSS1 promotes synapsis and is required for proper crossover distribution in meiosis.

Directory of Open Access Journals (Sweden)

Yann Duroc

2014-10-01

Full Text Available Meiotic crossovers (COs shape genetic diversity by mixing homologous chromosomes at each generation. CO distribution is a highly regulated process. CO assurance forces the occurrence of at least one obligatory CO per chromosome pair, CO homeostasis smoothes out the number of COs when faced with variation in precursor number and CO interference keeps multiple COs away from each other along a chromosome. In several organisms, it has been shown that cytoskeleton forces are transduced to the meiotic nucleus via KASH- and SUN-domain proteins, to promote chromosome synapsis and recombination. Here we show that the Arabidopsis kinesin AtPSS1 plays a major role in chromosome synapsis and regulation of CO distribution. In Atpss1 meiotic cells, chromosome axes and DNA double strand breaks (DSBs appear to form normally but only a variable portion of the genome synapses and is competent for CO formation. Some chromosomes fail to form the obligatory CO, while there is an increased CO density in competent regions. However, the total number of COs per cell is unaffected. We further show that the kinesin motor domain of AtPSS1 is required for its meiotic function, and that AtPSS1 interacts directly with WIP1 and WIP2, two KASH-domain proteins. Finally, meiocytes missing AtPSS1 and/or SUN proteins show similar meiotic defects suggesting that AtPSS1 and SUNs act in the same pathway. This suggests that forces produced by the AtPSS1 kinesin and transduced by WIPs/SUNs, are required to authorize complete synapsis and regulate maturation of recombination intermediates into COs. We suggest that a form of homeostasis applies, which maintains the total number of COs per cell even if only a part of the genome is competent for CO formation.

Effects of pentacene-doped PEDOT:PSS as a hole-conducting layer on the performance characteristics of polymer photovoltaic cells

OpenAIRE

Kim, Hyunsoo; Lee, Jungrae; Ok, Sunseong; Choe, Youngson

2012-01-01

We have investigated the effect of pentacene-doped poly(3,4-ethylenedioxythiophene:poly(4-styrenesulfonate) [PEDOT:PSS] films as a hole-conducting layer on the performance of polymer photovoltaic cells. By increasing the amount of pentacene and the annealing temperature of pentacene-doped PEDOT:PSS layer, the changes of performance characteristics were evaluated. Pentacene-doped PEDOT:PSS thin films were prepared by dissolving pentacene in 1-methyl-2-pyrrolidinone solvent and mixing with PEDO...

Sustaining the edge: factors influencing strategy selection in academic health centers.

Science.gov (United States)

Walsh, Anne M; Szabat, Kathryn

2002-01-01

Competition within the acute care sector as well as increased penetration by managed care organizations has influenced the structure and role of academic health centers during the past decade. The market factors confronting academic health centers are not dissimilar from conditions that confront other organizations competing in mature industries characterized by declining profitability and intense rivalry for market share. When confronted with intense competition or adverse external events, organizations in other industries have responded to potential threats by forming alliances, developing joint ventures, or merging with another firm to maintain their competitive advantage. Although mergers and acquisitions dominated the strategic landscape in the healthcare industry during the past decade, recent evidence suggests that other types of strategic ventures may offer similar economic and contracting benefits to member organizations. Academic health centers have traditionally been involved in network relationships with multiple partners via their shared technology, collaborative research, and joint educational endeavors. These quasi-organizational relationships appear to have provided a framework for strategic decisions and allowed executives of academic health centers to select strategies that were competitive yet closely aligned with their organizational mission. The analysis of factors that influenced strategy selection by executives of academic health centers suggests a deliberate and methodical approach to achieving market share objectives, expanding managed care contracts, and developing physician networks.

Planar silver nanowire, carbon nanotube and PEDOT:PSS nanocomposite transparent electrodes

Science.gov (United States)

Stapleton, Andrew J.; Yambem, Soniya D.; Johns, Ashley H.; Afre, Rakesh A.; Ellis, Amanda V.; Shapter, Joe G.; Andersson, Gunther G.; Quinton, Jamie S.; Burn, Paul L.; Meredith, Paul; Lewis, David A.

2015-04-01

Highly conductive, transparent and flexible planar electrodes were fabricated using interwoven silver nanowires and single-walled carbon nanotubes (AgNW:SWCNT) in a PEDOT:PSS matrix via an epoxy transfer method from a silicon template. The planar electrodes achieved a sheet resistance of 6.6 ± 0.0 Ω/□ and an average transmission of 86% between 400 and 800 nm. A high figure of merit of 367 Ω-1 is reported for the electrodes, which is much higher than that measured for indium tin oxide and reported for other AgNW composites. The AgNW:SWCNT:PEDOT:PSS electrode was used to fabricate low temperature (annealing free) devices demonstrating their potential to function with a range of organic semiconducting polymer:fullerene bulk heterojunction blend systems.

Simulation-Based Business Case for PSS: A System Dynamics Framework

DEFF Research Database (Denmark)

Rodrigues, Vinicius Picanco; Pigosso, Daniela Cristina Antelmi; McAloone, Tim C.

2017-01-01

of a business case for PSS implementation and management, based on a System Dynamics simulation framework. With amaturity-oriented theoretical perspective and the associated capability concepts, the study provides insights into how the development of PSScapabilities can potentially affect corporate performance...

The Optical Properties of Thin Film Reduced Graphene Oxide/Poly (3,4 Ethylenedioxtriophene):Poly (Styrene Sulfonate)(PEDOT:PSS) Fabricated by Spin Coating

Science.gov (United States)

Rokmana, Arinta W.; Asriani, A.; Suhendar, H.; Triyana, K.; Kusumaatmaja, A.; Santoso, I.

2018-04-01

Reduced Graphene Oxide (rGO) has been successfully synthesized from Graphite powder through chemical process using modified Hummers method by removing NaNO3 from reaction formula. Hydrazine hydrate 80 wt% has been chosen as reductor to eliminate the epoxy group in GO. FTIR and Uv-Vis spectroscopy result showed that Graphene Oxide (GO) and rGO were formed. Our produced rGO then used to fabricated the composite thin film rGO/PEDOT:PSS by spin coating at room temperature. The optical constant of thin film rGO/PEDOT:PSS were calculated from the absorbance spectrum of Uv-Visible spectra. The result showed that the value of coefficient absorbance of rGO dropped from 4.7×106 m-1 to 1.3×106 m-1 after doped with 0.02 mL PEDOT:PSS, then increase with the addition volume concentration of PEDOT:PSS. The value of extinction coefficient decrease from 0.31 to 0.08 after rGO doped with 0.02 ml PEDOT:PSS and then increase with the addition concentration of PEDOT:PSS. Our result show that thin film rGO/PEDOT:PSS was more transparent than that of thin film rGO.

First selection, then influence : Developmental differences in friendship dynamics regarding academic achievement

NARCIS (Netherlands)

Gremmen, Mariola Claudia; Dijkstra, Jan Kornelis; Steglich, Christian; Veenstra, René

This study concerns peer selection and influence dynamics in early adolescents' friendships regarding academic achievement. Using longitudinal social network analysis (RSiena), both selection and influence processes were investigated for students' average grades and their cluster-specific grades

Highly porous scaffolds of PEDOT:PSS for bone tissue engineering.

Science.gov (United States)

Guex, Anne Géraldine; Puetzer, Jennifer L; Armgarth, Astrid; Littmann, Elena; Stavrinidou, Eleni; Giannelis, Emmanuel P; Malliaras, George G; Stevens, Molly M

2017-10-15

Conjugated polymers have been increasingly considered for the design of conductive materials in the field of regenerative medicine. However, optimal scaffold properties addressing the complexity of the desired tissue still need to be developed. The focus of this study lies in the development and evaluation of a conductive scaffold for bone tissue engineering. In this study PEDOT:PSS scaffolds were designed and evaluated in vitro using MC3T3-E1 osteogenic precursor cells, and the cells were assessed for distinct differentiation stages and the expression of an osteogenic phenotype. Ice-templated PEDOT:PSS scaffolds presented high pore interconnectivity with a median pore diameter of 53.6±5.9µm and a total pore surface area of 7.72±1.7m 2 ·g -1 . The electrical conductivity, based on I-V curves, was measured to be 140µS·cm -1 with a reduced, but stable conductivity of 6.1µS·cm -1 after 28days in cell culture media. MC3T3-E1 gene expression levels of ALPL, COL1A1 and RUNX2 were significantly enhanced after 4weeks, in line with increased extracellular matrix mineralisation, and osteocalcin deposition. These results demonstrate that a porous material, based purely on PEDOT:PSS, is suitable as a scaffold for bone tissue engineering and thus represents a promising candidate for regenerative medicine. Tissue engineering approaches have been increasingly considered for the repair of non-union fractions, craniofacial reconstruction or large bone defect replacements. The design of complex biomaterials and successful engineering of 3-dimensional tissue constructs is of paramount importance to meet this clinical need. Conductive scaffolds, based on conjugated polymers, present interesting candidates to address the piezoelectric properties of bone tissue and to induce enhanced osteogenesis upon implantation. However, conductive scaffolds have not been investigated in vitro in great measure. To this end, we have developed a highly porous, electrically conductive scaffold

The Influence of Instructional Materials on Academic Performance of ...

African Journals Online (AJOL)

This research work investigated the influence of instructional materials (teaching aids) on students' academic performance in senior secondary school Chemistry in Cross River State. A two group pre-test post test quasi-experimental design was adopted for the study. One research question and one hypothesis were ...

Towards assessing Product/Service-Systems (PSS) within the Danish maritime industry: A PSS positioning map

DEFF Research Database (Denmark)

Hsuan, Juliana; Andersen, Jakob Axel Bejbro; Bey, Niki

2012-01-01

In response to requirements resulting from a changing business landscape from solely physical-product-based value creation towards performance-based value creation, this paper presents a questionnaire-based matrix, the PSS Categorization Matrix, that is developed in order to help organizations find...... their position in terms of the balance between product-related and service-related activities. Judging from a workshop carried out with companies from the maritime industry and researchers in the area, the approach seems promising, but requires improvements on questionnaire and Matrix. These need to incorporate...... further improvements regarding the factor of time and the applicability related to product/service portfolios, as opposed to single product/services. The authors already plan further research on the identified issues....

Conductive PEDOT:PSS coated polylactide (PLA) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) electrospun membranes: Fabrication and characterization

Energy Technology Data Exchange (ETDEWEB)

Chang, Hui Chung [Faculty of Bioscience and Medical Engineering, Universiti Teknologi Malaysia, 81300, Johor (Malaysia); Sun, Tao [Miniaturized Medical Devices Program, Institute of Microelectronics, Agency for Science, Technology and Research - A*STAR (Singapore); Sultana, Naznin, E-mail: naznin@biomedical.utm.my [Faculty of Bioscience and Medical Engineering, Universiti Teknologi Malaysia, 81300, Johor (Malaysia); Advanced Membrane Technology Research Center, Universiti Teknologi Malaysia, 81300, Johor (Malaysia); Lim, Mim Mim [Faculty of Bioscience and Medical Engineering, Universiti Teknologi Malaysia, 81300, Johor (Malaysia); Khan, Tareef Hayat [KALAM, Faculty of Alam Bina, Universiti Teknologi Malaysia, 81300, Johor (Malaysia); Ismail, Ahmad Fauzi [Advanced Membrane Technology Research Center, Universiti Teknologi Malaysia, 81300, Johor (Malaysia)

2016-04-01

In the current study, electrospinning technique was used to fabricate composite membranes by blending of a synthetic polymer, polylactic acid (PLA) and a natural polymer, poly(3-hydroxybutyrate-co-3-hydroxyvalerate), PHBV. Conductive membranes were prepared by dipping PLA/PHBV electrospun membranes into poly(3,4-ethylenedioxythiophene)–poly(styrenesulfonate) (PEDOT:PSS) solution, which is a biocompatible polymer. The coated and uncoated membranes were evaluated using several techniques. The electrical conductivity of the coated membranes was measured using a digital multimeter. In vitro cell cytotoxicity and cell viability were measured by culturing human skin fibroblast (HSF) cells onto the membranes using MTT assays. It was observed that electrospinning of 20% (w/v) PLA/PHBV with a weight ratio of 50:50 produced the most uniform fibers with no beads. It was observed that the wettability and surface roughness of the PEDOT:PSS coated PLA/PHBV membranes were greatly increased than uncoated membrane. The results of cell viability using MTT assay, cell attachment and cell proliferation showed that the conductive PEDOT:PSS coated PLA/PHBV membrane were more favorable for tissue engineering application than their uncoated counterparts. - Highlights: • Coating with PEDOT:PSS increased the wettability of PLA/PHBV membrane. • PEDOT:PSS rendered the PLA/PHBV membrane conductive. • PEDOT:PSS coated PLA/PHBV had significantly higher cell attachment.

Conductive PEDOT:PSS coated polylactide (PLA) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) electrospun membranes: Fabrication and characterization

International Nuclear Information System (INIS)

Chang, Hui Chung; Sun, Tao; Sultana, Naznin; Lim, Mim Mim; Khan, Tareef Hayat; Ismail, Ahmad Fauzi

2016-01-01

In the current study, electrospinning technique was used to fabricate composite membranes by blending of a synthetic polymer, polylactic acid (PLA) and a natural polymer, poly(3-hydroxybutyrate-co-3-hydroxyvalerate), PHBV. Conductive membranes were prepared by dipping PLA/PHBV electrospun membranes into poly(3,4-ethylenedioxythiophene)–poly(styrenesulfonate) (PEDOT:PSS) solution, which is a biocompatible polymer. The coated and uncoated membranes were evaluated using several techniques. The electrical conductivity of the coated membranes was measured using a digital multimeter. In vitro cell cytotoxicity and cell viability were measured by culturing human skin fibroblast (HSF) cells onto the membranes using MTT assays. It was observed that electrospinning of 20% (w/v) PLA/PHBV with a weight ratio of 50:50 produced the most uniform fibers with no beads. It was observed that the wettability and surface roughness of the PEDOT:PSS coated PLA/PHBV membranes were greatly increased than uncoated membrane. The results of cell viability using MTT assay, cell attachment and cell proliferation showed that the conductive PEDOT:PSS coated PLA/PHBV membrane were more favorable for tissue engineering application than their uncoated counterparts. - Highlights: • Coating with PEDOT:PSS increased the wettability of PLA/PHBV membrane. • PEDOT:PSS rendered the PLA/PHBV membrane conductive. • PEDOT:PSS coated PLA/PHBV had significantly higher cell attachment.

Influence of Family Background on the Academic Performance of ...

African Journals Online (AJOL)

The study was conducted to investigate the influence of family background on the academic performance of secondary school students in Nigeria. The study was carried out in the three senatorial districts of Kwara State. Three hundred respondents participated in this research. Descriptive statistics was used to analyze the ...

Towards a Lean Product Service Systems (PSS) Design: State of the Art, Opportunities and Challenges

OpenAIRE

Sassanelli, Claudio; Pezzotta, Giuditta; Rossi, Monica; Terzi, Sergio; Cavalieri, Sergio

2015-01-01

As for conventional products, the profit generation and the market success of Product Service Systems (PSS) critically depend on the decisions taken during the initial lifecycle stages, when PSSs are conceptualized, designed, developed and engineered. Successful cases show the adoption of lean techniques in the early stages of products development, impelling the authors to assess the application of the same approaches also to PSS development. For this reasons the paper aims to report the stat...

Relation between secondary doping and phase separation in PEDOT:PSS films

Energy Technology Data Exchange (ETDEWEB)

Donoval, Martin; Micjan, Michal; Novota, Miroslav; Nevrela, Juraj; Kovacova, Sona; Pavuk, Milan; Juhasz, Peter; Jagelka, Martin; Kovac, Jaroslav; Jakabovic, Jan [Institute of Electronics and Photonics, Slovak University of Technology, Ilkovičova 3, Bratislava 81219 (Slovakia); Cigan, Marek [Institute of Chemistry, Faculty of Natural Science, Comenius University, Mlynska dolina CH-2, Ilkovicova 6, Bratislava 84215 (Slovakia); Weis, Martin, E-mail: martin.weis@stuba.sk [Institute of Electronics and Photonics, Slovak University of Technology, Ilkovičova 3, Bratislava 81219 (Slovakia)

2017-02-15

Highlights: • Surface morphology of highly conductive polymer was investigated. • Phase separation due to secondary doping is an origin of conductivity enhancement. • Phase separation is not dependent on secondary dopant type. - Abstract: Conductive copolymer poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) has been proposed as an alternative to transparent conductive oxides because of its flexibility, transparency, and low-cost production. Four different secondary dopants, namely N,N-dimethylformamide, ethyleneglycol, sorbitol, and dimethyl sulfoxide, have been used to improve the conductivity. The relation between the structure changes and conductivity enhancement is studied in detail. Atomic force microscopy study of the thin film surface reveals the phase separation of PEDOT and PSS. We demonstrate that secondary doping induces the phase separation as well as the conductivity enhancement.

Significantly improved photovoltaic performance in polymer bulk heterojunction solar cells with graphene oxide /PEDOT:PSS double decked hole transport layer

Science.gov (United States)

Rafique, Saqib; Abdullah, Shahino Mah; Shahid, Muhammad Mehmood; Ansari, Mohammad Omaish; Sulaiman, Khaulah

2017-01-01

This work demonstrates the high performance graphene oxide (GO)/PEDOT:PSS doubled decked hole transport layer (HTL) in the PCDTBT:PC71BM based bulk heterojunction organic photovoltaic device. The devices were tested on merits of their power conversion efficiency (PCE), reproducibility, stability and further compared with the devices with individual GO or PEDOT:PSS HTLs. Solar cells employing GO/PEDOT:PSS HTL yielded a PCE of 4.28% as compared to either of individual GO or PEDOT:PSS HTLs where they demonstrated PCEs of 2.77 and 3.57%, respectively. In case of single GO HTL, an inhomogeneous coating of ITO caused the poor performance whereas PEDOT:PSS is known to be hygroscopic and acidic which upon direct contact with ITO reduced the device performance. The improvement in the photovoltaic performance is mainly ascribed to the increased charge carriers mobility, short circuit current, open circuit voltage, fill factor, and decreased series resistance. The well matched work function of GO and PEDOT:PSS is likely to facilitate the charge transportation and an overall reduction in the series resistance. Moreover, GO could effectively block the electrons due to its large band-gap of ~3.6 eV, leading to an increased shunt resistance. In addition, we also observed the improvement in the reproducibility and stability.

Significantly improved photovoltaic performance in polymer bulk heterojunction solar cells with graphene oxide /PEDOT:PSS double decked hole transport layer.

Science.gov (United States)

Rafique, Saqib; Abdullah, Shahino Mah; Shahid, Muhammad Mehmood; Ansari, Mohammad Omaish; Sulaiman, Khaulah

2017-01-13

This work demonstrates the high performance graphene oxide (GO)/PEDOT:PSS doubled decked hole transport layer (HTL) in the PCDTBT:PC 71 BM based bulk heterojunction organic photovoltaic device. The devices were tested on merits of their power conversion efficiency (PCE), reproducibility, stability and further compared with the devices with individual GO or PEDOT:PSS HTLs. Solar cells employing GO/PEDOT:PSS HTL yielded a PCE of 4.28% as compared to either of individual GO or PEDOT:PSS HTLs where they demonstrated PCEs of 2.77 and 3.57%, respectively. In case of single GO HTL, an inhomogeneous coating of ITO caused the poor performance whereas PEDOT:PSS is known to be hygroscopic and acidic which upon direct contact with ITO reduced the device performance. The improvement in the photovoltaic performance is mainly ascribed to the increased charge carriers mobility, short circuit current, open circuit voltage, fill factor, and decreased series resistance. The well matched work function of GO and PEDOT:PSS is likely to facilitate the charge transportation and an overall reduction in the series resistance. Moreover, GO could effectively block the electrons due to its large band-gap of ~3.6 eV, leading to an increased shunt resistance. In addition, we also observed the improvement in the reproducibility and stability.

Revisiting PSS and service design in the light of the SD-logic

DEFF Research Database (Denmark)

Costa, Nina; Patrício, Lia; Morelli, Nicola

2016-01-01

are only means to an end. Also, different approaches, methods and tools have been developed to design value propositions however they still lack to explicit the SDlogic principles. The design of solutions that provide value-in-use is at the centre of both Product Service System (PSS) approach and service...... comprehensive discussion about these two approaches and proposes a conceptual framework for integrating PSS organizational point of view; and SD human-centred focus to design better service.......Researchers and practitioners have increasingly recognized the importance of offering value propositions to customers that enable value co-creation as discussed in the service dominant logic (SD-logic). SD-logic recognizes customers as active co-creators and posits that products and services...

Systems of career influences: a conceptual model for evaluating the professional development of women in academic medicine.

Science.gov (United States)

Magrane, Diane; Helitzer, Deborah; Morahan, Page; Chang, Shine; Gleason, Katharine; Cardinali, Gina; Wu, Chih-Chieh

2012-12-01

Surprisingly little research is available to explain the well-documented organizational and societal influences on persistent inequities in advancement of women faculty. The Systems of Career Influences Model is a framework for exploring factors influencing women's progression to advanced academic rank, executive positions, and informal leadership roles in academic medicine. The model situates faculty as agents within a complex adaptive system consisting of a trajectory of career advancement with opportunities for formal professional development programming; a dynamic system of influences of organizational policies, practices, and culture; and a dynamic system of individual choices and decisions. These systems of influence may promote or inhibit career advancement. Within this system, women weigh competing influences to make career advancement decisions, and leaders of academic health centers prioritize limited resources to support the school's mission. The Systems of Career Influences Model proved useful to identify key research questions. We used the model to probe how research in academic career development might be applied to content and methods of formal professional development programs. We generated a series of questions and hypotheses about how professional development programs might influence professional development of health science faculty members. Using the model as a guide, we developed a study using a quantitative and qualitative design. These analyses should provide insight into what works in recruiting and supporting productive men and women faculty in academic medical centers.

Flexible, high performance Two-Ply Yarn Supercapacitors based on irradiated Carbon Nanotube Yarn and PEDOT/PSS

International Nuclear Information System (INIS)

Su, Fenghua; Miao, Menghe

2014-01-01

Graphical abstract: - Highlights: • Two-ply supercapacitors based on CNT yarn were prepared by a simple method. • The two-ply supercapacitors are high-performance, flexible and thread-like. • Gamma irradiation of CNT yarn improves the capacitance of the resulting supercapacitor. • PEDOT/PSS coated on the yarn surface further improve the capacitance of supercapacitors. • The two-ply supercapacitors can be easily woven or knitted into conventional textile fabrics. - Abstract: We present a simple design and a fabrication method for a high-performance, flexible, two-ply yarn supercapacitor based on irradiated CNT yarn and conductive polymer Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT/PSS). The CNT yarn is treated with gamma irradiation and the yarn surface is coated with the PEDOT/PSS to improve the energy storage capacitance of the as-spun yarn supercapacitor. A layer of PVA gel is coated on the surfaces of the CNT yarn and the composite yarn to form a separation layer containing electrolyte. The results show that the gamma irradiation greatly increases the electrical conductivity and improved the gram capacitance of the as-spun CNT two-ply yarn supercapacitor. The coating of PEDOT/PSS on the surface of the pure and irradiated CNT yarns further significantly improves the capacitance of the supercapacitors. The two-ply yarn supercapacitor constructed from the irradiation CNT yarn coated by PEDOT/PSS exhibits the large capacitance and high cyclic charge-discharge stability. Moreover, these two-ply yarn supercapacitors with fine diameters are highly flexible and can be easily woven or knitted into textile fabrics for uses in wearable electronics

Influencing Academic Motivation: The Effects of Student-Faculty Interaction

Science.gov (United States)

Trolian, Teniell L.; Jach, Elizabeth A.; Hanson, Jana M.; Pascarella, Ernest T.

2016-01-01

Using data from the Wabash National Study of Liberal Arts Education, we examined the influence of student-faculty interactions on student academic motivation over 4 years of college. Results suggest that several forms of student-faculty interaction, such as quality of faculty contact, frequency of faculty contact, research with faculty, personal…

High performance silicon–organic hybrid solar cells via improving conductivity of PEDOT:PSS with reduced graphene oxide

International Nuclear Information System (INIS)

Jiang, Xinyu; Wang, Zilei; Han, Wenhui; Liu, Qiming; Lu, Shuqi; Wen, Yuxiang; Hou, Juan; Huang, Fei; Peng, Shanglong; He, Deyan; Cao, Guozhong

2017-01-01

Highlights: • The fabricated Si–organic hybrid solar cells with 2 mg/ml rGO addition yielded a power conversion efficiency of 11.95% with a J_s_c of 31.94 mA cm"−"2, a V_o_c of 579 mV and a FF of 0.648, about 27.8% increase from 9.35% in pristine hybrid solar cells. • The electrical conductivity of PEDOT:PSS improved 35% when appropriate amount rGO was added to PEDOT:PSS, the electron recombination at the junction interface of the device was suppressed by the appropriate amount rGO flakes addition. • The rGO flakes also serve as an antireflection coating to further reduce the reflectance in the wavelength range of 300–550 nm, leading to further enhanced performances of hybrid solar cells. - Abstract: The optical and electrical properties of PEDOT:PSS organic layer play a very important role in determining the power conversion efficiency (PCE) of Si–organic hybrid solar cells (HSCs). In the present study, properties of PEDOT:PSS thin films with reduced graphene oxide (rGO) and their impacts on the performances of the resultant Si–organic HSCs have been systematically investigated. The electrical conductivity of PEDOT:PSS improved 35% when rGO was added to PEDOT:PSS, and the fabricated HSCs with 2 mg/ml rGO addition yielded an PCE of 11.95% with a J_s_c of 31.94 mA cm"−"2, a V_o_c of 579 mV and a FF of 0.648. However, excess rGO would deteriorate the solar cells performances and it might create additional defects and prevent carriers being collected. The Raman spectroscopy, sheet resistance and EQE analyses with rGO suggested that the interaction between the conductive rGO flakes and the aromatic PEDOT most probably not only provide additional charge transport pathways in hole transport layer to improve carrier mobility leading to a higher carrier collection efficiency, but also suppress the electron recombination at the junction interface. In addition, the rGO serve as an antireflection coating to reduce the reflectance of PEDOT:PSS thin film

High performance silicon–organic hybrid solar cells via improving conductivity of PEDOT:PSS with reduced graphene oxide

Energy Technology Data Exchange (ETDEWEB)

Jiang, Xinyu; Wang, Zilei; Han, Wenhui; Liu, Qiming; Lu, Shuqi; Wen, Yuxiang [School of Physical Science and Technology, Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Hou, Juan [School of Science, Key Laboratory of Ecophysics, Shihezi University, Xinjiang 832003 (China); Huang, Fei [Department of Materials Science and Engineering, University of Washington, Seattle, WA 98195-2120 (United States); Peng, Shanglong, E-mail: pengshl@lzu.edu.cn [School of Physical Science and Technology, Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000 (China); He, Deyan [School of Physical Science and Technology, Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Cao, Guozhong, E-mail: gzcao@u.washington.edu [Department of Materials Science and Engineering, University of Washington, Seattle, WA 98195-2120 (United States)

2017-06-15

Highlights: • The fabricated Si–organic hybrid solar cells with 2 mg/ml rGO addition yielded a power conversion efficiency of 11.95% with a J{sub sc} of 31.94 mA cm{sup −2}, a V{sub oc} of 579 mV and a FF of 0.648, about 27.8% increase from 9.35% in pristine hybrid solar cells. • The electrical conductivity of PEDOT:PSS improved 35% when appropriate amount rGO was added to PEDOT:PSS, the electron recombination at the junction interface of the device was suppressed by the appropriate amount rGO flakes addition. • The rGO flakes also serve as an antireflection coating to further reduce the reflectance in the wavelength range of 300–550 nm, leading to further enhanced performances of hybrid solar cells. - Abstract: The optical and electrical properties of PEDOT:PSS organic layer play a very important role in determining the power conversion efficiency (PCE) of Si–organic hybrid solar cells (HSCs). In the present study, properties of PEDOT:PSS thin films with reduced graphene oxide (rGO) and their impacts on the performances of the resultant Si–organic HSCs have been systematically investigated. The electrical conductivity of PEDOT:PSS improved 35% when rGO was added to PEDOT:PSS, and the fabricated HSCs with 2 mg/ml rGO addition yielded an PCE of 11.95% with a J{sub sc} of 31.94 mA cm{sup −2}, a V{sub oc} of 579 mV and a FF of 0.648. However, excess rGO would deteriorate the solar cells performances and it might create additional defects and prevent carriers being collected. The Raman spectroscopy, sheet resistance and EQE analyses with rGO suggested that the interaction between the conductive rGO flakes and the aromatic PEDOT most probably not only provide additional charge transport pathways in hole transport layer to improve carrier mobility leading to a higher carrier collection efficiency, but also suppress the electron recombination at the junction interface. In addition, the rGO serve as an antireflection coating to reduce the reflectance of

PEDOT:PSS self-assembled films to methanol crossover reduction in Nafion{sup ®} membranes

Energy Technology Data Exchange (ETDEWEB)

Almeida, Tiago P. [Universidade Federal de São Carlos, Sorocaba, SP (Brazil); Miyazaki, Celina M. [Universidade Estadual Paulista, POSMAT, SP (Brazil); Paganin, Valdecir A. [Universidade de São Paulo, IQSC, São Carlos, SP (Brazil); Ferreira, Marystela [Universidade Federal de São Carlos, Sorocaba, SP (Brazil); Saeki, Margarida J. [Universidade Estadual Paulista, Instituto de Biociências, Botucatu, SP (Brazil); Perez, Joelma [Universidade de São Paulo, IQSC, São Carlos, SP (Brazil); Riul, Antonio, E-mail: riul@ifi.unicamp.br [Universidade Estadual de Campinas, IFGW, Campinas (Brazil)

2014-12-30

Highlights: • PAH/PEDOT:PSS LbL films were regularly multilayered onto Nafion. • The LbL modified membranes were succesfully applied to reduce methanol crossover in Nafion. • PAH/PEDO:PSS films also decreased the proton conduction, reducing in 15% the DMFC performance. - Abstract: Alternative energy sources are on a global demand, with fuel cells as promising devices from mobile to stationary applications. Nafion{sup ®} is at the heart of many of these appliances, being mostly used due to its high proton conduction and good chemical stability at ambient temperature in proton exchange membranes (PEM). Therefore, methanol permeation throughout Nafion{sup ®} films reduces drastically the performance of direct methanol fuel cells (DMFC). We present here the deposition of layer-by-layer (LbL) nanostructured thin films of poly(allylamine hydrochloride) (PAH) and poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) onto commercial Nafion{sup ®} 212 membranes. It was observed a good adherence of the LbL films onto Nafion{sup ®} 212, with UV–vis results displaying a linear characteristic growth, indicative that the same amount of material was deposited at each deposition step during the layer-by-layer assembly. In addition, the LbL films also act as a good barrier to avoid methanol crossover, with an observed reduction in the methanol permeation from 5.5 × 10{sup −6} cm{sup 2} s{sup −1} to 3.2 × 10{sup −6} cm{sup 2} s{sup −1}, respectively to pristine Nafion{sup ®} 212 and a 5-bilayer PAH/PEDOT:PSS LbL film deposited on Nafion{sup ®}212. The measured power density in a DMFC set-up was not significantly changed (∼12 mW cm{sup −2}) due to the LbL films, since the PAH/PEDOT:PSS nanostructure is impeding water and ion transport, consequently affecting the proton conduction throughout the membrane.

Vacuum-assisted bilayer PEDOT:PSS/cellulose nanofiber composite film for self-standing, flexible, conductive electrodes.

Science.gov (United States)

Ko, Youngsang; Kim, Dabum; Kim, Ung-Jin; You, Jungmok

2017-10-01

Sustainable cellulose nanofiber (CNF)-based composites as functional conductive materials have garnered considerable attention recently for their use in soft electronic devices. In this work, self-standing, highly flexible, and conductive PEDOT:PSS-CNF composite films were developed using a simple vacuum-assisted filtration method. Two different composite films were successfully fabricated and then tested: 1) a single-layer composite composed of a mixture of PEDOT:PSS and CNF phases and 2) a bilayer composite composed of an upper PEDOT:PSS membrane layer and a CNF matrix sub-layer. The latter composite was constructed by electrostatic/hydrogen bonding interactions between PEDOT:PSS and CNFs coupled with sequential vacuum-assisted filtration. Our results demonstrated that the resultant bilayer composite film exhibited a competitive electrical conductivity (ca. 22.6Scm -1 ) compared to those of previously reported cellulose-based composites. Furthermore, decreases in the electrical properties were not observed in the composite films when they were bent up to 100 times at an angle of 180° and bent multiple times at an angle of 90°, clearly demonstrating their excellent mechanical flexibility. This study provides a straightforward method of fabricating highly flexible, lightweight, and conductive films, which have the potential to be used in high-performance soft electronic systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Components of Communication Systems in Universities: Their Influence on Academic Work Life

Science.gov (United States)

Uslu, Baris

2018-01-01

This research aimed to identify the components of communication systems in universities and to explore their influence on academic life. To collect data, interviews were carried out with academics from Australian universities. Thematic descriptive and content analyses were performed on the data-set. Analyses showed that the human relations unit,…

Systems of Career Influences: A Conceptual Model for Evaluating the Professional Development of Women in Academic Medicine

Science.gov (United States)

Helitzer, Deborah; Morahan, Page; Chang, Shine; Gleason, Katharine; Cardinali, Gina; Wu, Chih-Chieh

2012-01-01

Abstract Background Surprisingly little research is available to explain the well-documented organizational and societal influences on persistent inequities in advancement of women faculty. Methods The Systems of Career Influences Model is a framework for exploring factors influencing women's progression to advanced academic rank, executive positions, and informal leadership roles in academic medicine. The model situates faculty as agents within a complex adaptive system consisting of a trajectory of career advancement with opportunities for formal professional development programming; a dynamic system of influences of organizational policies, practices, and culture; and a dynamic system of individual choices and decisions. These systems of influence may promote or inhibit career advancement. Within this system, women weigh competing influences to make career advancement decisions, and leaders of academic health centers prioritize limited resources to support the school's mission. Results and Conclusions The Systems of Career Influences Model proved useful to identify key research questions. We used the model to probe how research in academic career development might be applied to content and methods of formal professional development programs. We generated a series of questions and hypotheses about how professional development programs might influence professional development of health science faculty members. Using the model as a guide, we developed a study using a quantitative and qualitative design. These analyses should provide insight into what works in recruiting and supporting productive men and women faculty in academic medical centers. PMID:23101486

Fabrication of flexible conductive films derived from poly(3,4-ethylenedioxythiophene)–poly(styrenesulfonic acid) (PEDOT:PSS) on the nonwoven fabrics substrate

Energy Technology Data Exchange (ETDEWEB)

Wu, Chieh-Han [Institute of Polymer Science and Engineering, National Taiwan University, Taipei 106, Taiwan, ROC (China); Shen, Hsiu-Ping [Department of Chemical Engineering, National Taiwan University, Taipei 106, Taiwan, ROC (China); Don, Trong-Ming, E-mail: tmdon@mail.tku.edu.tw [Department of Chemical and Materials Engineering, Tamkang University, New Taipei 251, Taiwan, ROC (China); Chiu, Wen-Yen, E-mail: ycchiu@ntu.edu.tw [Institute of Polymer Science and Engineering, National Taiwan University, Taipei 106, Taiwan, ROC (China); Department of Chemical Engineering, National Taiwan University, Taipei 106, Taiwan, ROC (China); Department of Materials Science and Engineering, National Taiwan University, Taipei 106, Taiwan, ROC (China)

2013-12-16

In this research, conducting poly(3,4-ethylenedioxythiophene)–poly(styrenesulfonic acid) (PEDOT:PSS) aqueous dispersion was synthesized at first via chemical oxidative polymerization and followed by mixing it with poly(styrene-r-butyl acrylate) P(St-BA) aqueous latex, creating a conductive material with outstanding stretchability. The elastic conductive composite were then film formed on the glass and poly(ethylene terephthalate) (PET) nonwoven fabric substrate by spin coating and dip coating, respectively. Composite films with various contents of PEDOT:PSS polymer (10–100 wt.%) had been prepared. From the conductivity measurements, the conductivity was still kept as high as 88 S cm{sup −1} even the PEDOT:PSS content was lowered to 10 wt.%. Furthermore, the elasticity of conductive films on the PET-nonwoven fabric substrate was evaluated by the 180° bending test repeating 100 times. With introducing soft P(St-BA) material in the PEDOT:PSS phase, the surface resistance increased merely 3–6 times after bending 100 times, while the surface resistance for pure PEDOT:PSS film could reach 18–20 times. - Highlights: • Flexible PEDOT:PSS based material had been coated on the PET-nonwoven fabrics. • The integrity of conductive circuit on fabrics was evaluated by bending test. • With adding rubbery material, the flexibility of PEDOT:PSS coating was enhanced.

Fabrication of flexible conductive films derived from poly(3,4-ethylenedioxythiophene)–poly(styrenesulfonic acid) (PEDOT:PSS) on the nonwoven fabrics substrate

International Nuclear Information System (INIS)

Wu, Chieh-Han; Shen, Hsiu-Ping; Don, Trong-Ming; Chiu, Wen-Yen

2013-01-01

In this research, conducting poly(3,4-ethylenedioxythiophene)–poly(styrenesulfonic acid) (PEDOT:PSS) aqueous dispersion was synthesized at first via chemical oxidative polymerization and followed by mixing it with poly(styrene-r-butyl acrylate) P(St-BA) aqueous latex, creating a conductive material with outstanding stretchability. The elastic conductive composite were then film formed on the glass and poly(ethylene terephthalate) (PET) nonwoven fabric substrate by spin coating and dip coating, respectively. Composite films with various contents of PEDOT:PSS polymer (10–100 wt.%) had been prepared. From the conductivity measurements, the conductivity was still kept as high as 88 S cm −1 even the PEDOT:PSS content was lowered to 10 wt.%. Furthermore, the elasticity of conductive films on the PET-nonwoven fabric substrate was evaluated by the 180° bending test repeating 100 times. With introducing soft P(St-BA) material in the PEDOT:PSS phase, the surface resistance increased merely 3–6 times after bending 100 times, while the surface resistance for pure PEDOT:PSS film could reach 18–20 times. - Highlights: • Flexible PEDOT:PSS based material had been coated on the PET-nonwoven fabrics. • The integrity of conductive circuit on fabrics was evaluated by bending test. • With adding rubbery material, the flexibility of PEDOT:PSS coating was enhanced

Bringing service design to manufacturing companies: integrating PSS and service design approaches

DEFF Research Database (Denmark)

Costa, Nina; Patrício, Lia; Morelli, Nicola

2018-01-01

in a manufacturing industry. This paper details how the application supports the design of product–service system solutions from the exploration to the implementation stages, highlighting the physical evidence of service, and contributes to advance design research at the intersection of PSS and Service Design.......Manufacturing companies increasingly try to innovate in their offers to consumers by creating more complete solutions that combine product and service components. However, shifting from a product-centric perspective to a solution-oriented perspective is challenging. The present study adopted...... a design research methodology and built on Service-Dominant logic, integrating the human-oriented perspective of Service Design with an organizational network-oriented perspective of Product–Service System. It creates a new Integrative PSS approach, evolves design models, and provides an application...

Microscopic understanding of the anisotropic conductivity of PEDOT:PSS thin films

NARCIS (Netherlands)

Nardes, A.M.; Kemerink, M.; Janssen, R.A.J.; Bastiaansen, J.J.A.M.; Kiggen, N.M.M.; Langeveld, B.M.W.; Breemen, A.J.J.M. van; Kok, M.M. de

2007-01-01

The anisotropic conductivity of spin-coated poly(3,4- ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) thin films by temperature-dependent conductivity measurements, has been analyzed. A detailed 3D morphological model was derived from topographic scanning tunneling microscopy (STM) and

Factors that influence career progression among postdoctoral clinical academics: a scoping review of the literature

OpenAIRE

Ranieri, V.; Barratt, H.; Fulop, N.; Rees, G.

2016-01-01

Background: The future of academic medicine is uncertain. Concerns regarding the future availability of qualified and willing trainee clinical academics have been raised worldwide. Of significant concern is our failure to retain postdoctoral trainee clinical academics, who are likely to be our next generation of leaders in scientific discovery. / Objectives: To review the literature about factors that may influence postdoctoral career progression in early career clinical academics. / Design: ...

Factors that influence career progression among postdoctoral clinical academics: a scoping review of the literature

OpenAIRE

Ranieri, Veronica; Barratt, Helen; Fulop, Naomi; Rees, Geraint

2016-01-01

Background The future of academic medicine is uncertain. Concerns regarding the future availability of qualified and willing trainee clinical academics have been raised worldwide. Of significant concern is our failure to retain postdoctoral trainee clinical academics, who are likely to be our next generation of leaders in scientific discovery. Objectives To review the literature about factors that may influence postdoctoral career progression in early career clinical academics. Design This st...

Stable inverted polymer/fullerene solar cells using a cationic polythiophene modified PEDOT:PSS cathodic interface

Energy Technology Data Exchange (ETDEWEB)

Rider, David A.; Worfolk, Brian J.; Buriak, Jillian M. [Department of Chemistry, University of Alberta, Edmonton, Alberta (Canada); NRC National Institute for Nanotechnology, Edmonton, Alberta (Canada); Harris, Kenneth D.; Shahbazi, Kevin; Fleischauer, Michael D. [NRC National Institute for Nanotechnology, Edmonton, Alberta (Canada); Lalany, Abeed [Department of Electrical and Computer Engineering, University of Alberta, Edmonton (Canada); Brett, Michael J. [NRC National Institute for Nanotechnology, Edmonton, Alberta (Canada); Department of Electrical and Computer Engineering, University of Alberta, Edmonton (Canada)

2010-08-09

A cationic and water-soluble polythiophene [poly[3-(6-pyridiniumylhexyl)thiophene bromide](P3PHT{sup +}Br{sup -})] is synthesized and used in combination with anionic poly(3,4-ethylenedioxythiophene):poly(p-styrenesulfonate) (PEDOT:PSS){sup -} to produce hybrid coatings on indium tin oxide (ITO). Two coating strategies are established: i) electrostatic layer-by-layer assembly with colloidal suspensions of (PEDOT:PSS){sup -}, and ii) modification of an electrochemically prepared (PEDOT:PSS){sup -} film on ITO. The coatings are found to modify the work function of ITO such that it could act as a cathode in inverted 2,5-diyl-poly(3-hexylthiophene) (P3HT)/[6,6]-phenyl-C{sub 61}-butyric acid methyl ester (PCBM) polymer photovoltaic cells. The interfacial modifier created from the layer-by-layer assembly route is used to produce efficient inverted organic photovoltaic devices (power conversion efficiency {proportional_to}2%) with significant long-term stability in excess of 500 h. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

Impact of PSS and STATCOM Devices to the Dynamic Performance of a Multi-Machine Power System

Directory of Open Access Journals (Sweden)

G. Shahgholian

2017-12-01

Full Text Available This paper studies the impact of leveraging both static syn­ch­ron­ous compensator (STATCOM and power system stabilizer (PSS on multi-machine power systems. Considering a sta­ndard IEEE 9-bus test power network, classic and intelligent controllers are applied to achieve the desirable system performance. Simulated tests show the usefulness of STATCOM on network power quality in terms of voltage profile. In addition, it is shown that it can significantly improve the damping oscillations of synchronous generator under normal and abnormal network conditions. As shown, the PSS also contributes to improving the synch­ron­o­u­s generator parameters. It is also observed that using intelligent controllers with STATCOM and PSS leads to a better perfor­ma­nc­e relative to the classic controllers.

Stable angular emission spectra in white organic light-emitting diodes using graphene/PEDOT:PSS composite electrode.

Science.gov (United States)

Cho, Hyunsu; Lee, Hyunkoo; Lee, Jonghee; Sung, Woo Jin; Kwon, Byoung-Hwa; Joo, Chul-Woong; Shin, Jin-Wook; Han, Jun-Han; Moon, Jaehyun; Lee, Jeong-Ik; Cho, Seungmin; Cho, Nam Sung

2017-05-01

In this work, we suggest a graphene/ poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) composite as a transparent electrode for stabilizing white emission of organic light-emitting diodes (OLEDs). Graphene/PEDOT:PSS composite electrodes have increased reflectance when compared to graphene itself, but their reflectance is still lower than that of ITO itself. Changes in the reflectance of the composite electrode have the advantage of suppressing the angular spectral distortion of white emission OLEDs and achieving an efficiency of 16.6% for white OLEDs, comparable to that achieved by graphene-only electrodes. By controlling the OLED structure to compensate for the two-beam interference effect, the CIE color coordinate change (Δxy) of OLEDs based on graphene/PEDOT:PSS composite electrodes is 0.018, less than that based on graphene-only electrode, i.e.,0.027.

Effect of Nonionic Surfactant Additive in PEDOT:PSS on PFO Emission Layer in Organic-Inorganic Hybrid Light-Emitting Diode.

Science.gov (United States)

Cho, Seong Rae; Porte, Yoann; Kim, Yun Cheol; Myoung, Jae-Min

2018-03-21

Poly(9,9-dioctylfluorene) (PFO) has attracted significant interests owing to its versatility in electronic devices. However, changes in its optical properties caused by its various phases and the formation of oxidation defects limit the application of PFO in light-emitting diodes (LEDs). We investigated the effects of the addition of Triton X-100 (hereinafter shortened as TX) in poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) to induce interlayer diffusion between PEDOT:PSS and PFO to enhance the stability of the PFO phase and suppress its oxidation. Photoluminescence (PL) measurement on PFO/TX-mixed PEDOT:PSS layers revealed that, upon increasing the concentration of TX in the PEDOT:PSS layer, the β phase of PFO could be suppressed in favor of the glassy phase and the wide PL emission centered at 535 nm caused by ketone defects formed by oxidation was decreased considerably. LEDs were then fabricated using PFO as an emission layer, TX-mixed PEDOT:PSS as hole-transport layer, and zinc oxide (ZnO) nanorods as electron-transport layer. As the TX concentration reached 3 wt %, the devices exhibited dramatic increases in current densities, which were attributed to the enhanced hole injection due to TX addition, along with a shift in the dominant emission wavelength from a green electroluminescence (EL) emission centered at 518 nm to a blue EL emission centered at 448 nm. The addition of TX in PEDOT:PSS induced a better hole injection in the PFO layer, and through interlayer diffusion, stabilized the glassy phase of PFO and limited the formation of oxidation defects.

Parental Influence, School Readiness and Early Academic Achievement of African American Boys

Science.gov (United States)

Joe, Emanique M.; Davis, James Earl

2009-01-01

This study examined the relationship between parental influence and the school readiness of African American boys, using data from the Early Childhood Longitudinal Study: ECLS-K, Parents' influence, via their academic beliefs and behaviors, was associated with the cognitive performance of African American boys during kindergarten. While previous…

Towards assessing Product/Service Systems (PSS) within the Danish Maritime Industry

DEFF Research Database (Denmark)

Hsuan, Juliana; Andersen, Jakob B.; Bey, Niki

2012-01-01

In response to requirements resulting from a changing business landscape from solely physical-product-based value creation towards perfoprmance-based value creation, this paper presents a questionaire-based matrix, the PSS Categorization Matric, that is developed in order to help organizations fi...

The Diffusion of Academic Achievements: Social Selection and Influence in Student Networks

OpenAIRE

Sofia Dokuka; Diliara Valeeva; Maria Yudkevich

2015-01-01

Peer group effects show the influence of student social environments on their individual achievements. Traditionally, a social environment is considered by researchers of peer effects as exogenously given. However, significant peers that affect performance are often those that are deliberately chosen. Students might choose their friends among peers with similar academic achievements. A dynamic analysis of student social networks and academic achievements is needed to disentangle social select...

Tailoring the Electrochemical and Mechanical Properties of PEDOT:PSS Films for Bioelectronics

KAUST Repository

Elmahmoudy, Mohammed; Inal, Sahika; Charrier, Anne; Uguz, Ilke; Malliaras, George G.; Sanaur, Sé bastien

2017-01-01

The effect of 3-glycidoxypropyltrimethoxysilane (GOPS) content in poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) dispersions on the properties of films spun cast from these formulations is investigated. It has been found out

Flexible nonvolatile memory devices based on Au/PMMA nanocomposites deposited on PEDOT:PSS/Ag nanowire hybrid electrodes

International Nuclear Information System (INIS)

Sung, Sihyun; Kim, Tae Whan

2017-01-01

Highlights: • Flexible nonvolatile memory (NVM) devices fabricated utilizing Au nanoparticles (AuNPs) embedded in a PMMA layer were fabricated. • The insertion of the PEDOT:PSS layer enhanced the surface uniformity of the AgNW bottom electrode, resulting in improved device performances. • Current-voltage curves for the Al/PMMA:AuNP/PEDOT:PSS/AgNW/PET devices showed clockwise current hysteresis behaviors. • ON/OFF ratio of 1 × 10 3 was maintained for retention times longer than 1 × 10 4 s. • Memory characteristics of the NVM devices before and after bending were similar. - Abstract: Flexible nonvolatile memory (NVM) devices fabricated utilizing Au nanoparticles (AuNPs) embedded in a poly(methylmethacrylate) (PMMA) layer were fabricated on a silver nanowire (AgNW) or a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/AgNW coated on poly(ethylene terephthalate) (PET) substrates. The transmittance and the sheet resistance of the PEDOT:PSS/AgNW hybrid layer were approximately 89% and 50 Ω/sq, respectively, which were comparable to the values for commercial indium-tin-oxide (ITO) electrodes. Current-voltage curves for the Al/PMMA:AuNP/PEDOT:PSS/AgNW/PET devices at 300 K showed clockwise current hysteresis behaviors due to the existence of the AuNPs. The endurance number of ON/OFF switching for the NVM devices was above 30 cycles. An ON/OFF ratio of 1 × 10 3 was maintained for retention times longer than 1 × 10 4 s. The maximum memory margins of the NVM devices before and after bending were approximately 3.4 × 10 3 and 1.4 × 10 3 , respectively. The retention times of the devices before and after bending remained same 1 × 10 4 s. The memory margin and the stability of flexible NVMs fabricated on AgNW electrodes were enhanced due to the embedded PEDOT:PSS buffer layer.

Flexible nonvolatile memory devices based on Au/PMMA nanocomposites deposited on PEDOT:PSS/Ag nanowire hybrid electrodes

Energy Technology Data Exchange (ETDEWEB)

Sung, Sihyun; Kim, Tae Whan, E-mail: twk@hanyang.ac.kr

2017-07-31

Highlights: • Flexible nonvolatile memory (NVM) devices fabricated utilizing Au nanoparticles (AuNPs) embedded in a PMMA layer were fabricated. • The insertion of the PEDOT:PSS layer enhanced the surface uniformity of the AgNW bottom electrode, resulting in improved device performances. • Current-voltage curves for the Al/PMMA:AuNP/PEDOT:PSS/AgNW/PET devices showed clockwise current hysteresis behaviors. • ON/OFF ratio of 1 × 10{sup 3} was maintained for retention times longer than 1 × 10{sup 4} s. • Memory characteristics of the NVM devices before and after bending were similar. - Abstract: Flexible nonvolatile memory (NVM) devices fabricated utilizing Au nanoparticles (AuNPs) embedded in a poly(methylmethacrylate) (PMMA) layer were fabricated on a silver nanowire (AgNW) or a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/AgNW coated on poly(ethylene terephthalate) (PET) substrates. The transmittance and the sheet resistance of the PEDOT:PSS/AgNW hybrid layer were approximately 89% and 50 Ω/sq, respectively, which were comparable to the values for commercial indium-tin-oxide (ITO) electrodes. Current-voltage curves for the Al/PMMA:AuNP/PEDOT:PSS/AgNW/PET devices at 300 K showed clockwise current hysteresis behaviors due to the existence of the AuNPs. The endurance number of ON/OFF switching for the NVM devices was above 30 cycles. An ON/OFF ratio of 1 × 10{sup 3} was maintained for retention times longer than 1 × 10{sup 4} s. The maximum memory margins of the NVM devices before and after bending were approximately 3.4 × 10{sup 3} and 1.4 × 10{sup 3}, respectively. The retention times of the devices before and after bending remained same 1 × 10{sup 4} s. The memory margin and the stability of flexible NVMs fabricated on AgNW electrodes were enhanced due to the embedded PEDOT:PSS buffer layer.

Does academic assessment system type affect levels of academic stress in medical students? A cross-sectional study from Pakistan

Directory of Open Access Journals (Sweden)

Madiha Ali

2015-06-01

Full Text Available Introduction: Stress among medical students induced by academic pressures is on the rise among the student population in Pakistan and other parts of the world. Our study examined the relationship between two different systems employed to assess academic performance and the levels of stress among students at two different medical schools in Karachi, Pakistan. Methods: A sample consisting of 387 medical students enrolled in pre-clinical years was taken from two universities, one employing the semester examination system with grade point average (GPA scores (a tiered system and the other employing an annual examination system with only pass/fail grading. A pre-designed, self-administered questionnaire was distributed. Test anxiety levels were assessed by The Westside Test Anxiety Scale (WTAS. Overall stress was evaluated using the Perceived Stress Scale (PSS. Results: There were 82 males and 301 females while four did not respond to the gender question. The mean age of the entire cohort was 19.7±1.0 years. A total of 98 participants were from the pass/fail assessment system while 289 were from the GPA system. There was a higher proportion of females in the GPA system (85% vs. 59%; p<0.01. Students in the pass/fail assessment system had a lower score on the WTAS (2.4±0.8 vs. 2.8±0.7; p=0.01 and the PSS (17.0±6.7 vs. 20.3±6.8; p<0.01, indicating lower levels of test anxiety and overall stress than in students enrolled in the GPA assessment system. More students in the pass/fail system were satisfied with their performance than those in the GPA system. Conclusion: Based on the present study, we suggest governing bodies to revise and employ a uniform assessment system for all the medical colleges to improve student academic performance and at the same time reduce stress levels. Our results indicate that the pass/fail assessment system accomplishes these objectives.

Degradation and Its Control of Ultraviolet Avalanche Photodiodes Using PEDOT:PSS/ZnSSe Organic-Inorganic Hybrid Structure

Science.gov (United States)

Abe, Tomoki; Uchida, Shigeto; Tanaka, Keita; Fujisawa, Takanobu; Kasada, Hirofumi; Ando, Koshi; Akaiwa, Kazuaki; Ichino, Kunio

2018-05-01

We investigated device degradation in PEDOT:PSS/ZnSSe organic-inorganic hybrid ultraviolet avalanche photodiodes (UV-APDs). ZnSSe/n-GaAs wafers were grown by molecular beam epitaxy, and PEDOT:PSS window layers were formed by inkjet technique. We observed rapid degradation with APD-mode stress (˜ 30 V) in the N2 (4 N) atmosphere, while we observed no marked change in forward bias current stress and photocurrent stress. In the case of a vacuum condition, we observed no detectable degradation in the dark avalanche current with APD-mode stress. Therefore, the degradation in the PEDOT:PSS/ZnSSe interface under the APD-mode stress was caused by the residual water vapor or oxygen in the N2 atmosphere and could be controlled by vacuum packaging.

Deposition of PEDOT: PSS Nanoparticles as a Conductive Microlayer Anode in OLEDs Device by Desktop Inkjet Printer

Directory of Open Access Journals (Sweden)

S. Ummartyotin

2011-01-01

Full Text Available A simple microfabrication technique for delivering macromolecules and patterning microelectrode arrays using desktop inkjet printer was described. Aqueous solution of nanoparticle of poly (3,4-ethylenedioxythiophene (PEDOT doped with polystyrene sulfonic acid (PSS was prepared while its particle size, the surface tension, and the viscosity of the solution were adjusted to be suitable for deposition on a flexible cellulose nanocomposite substrate via inkjet printer. The statistical average of PEDOT: PSS particle size of 100 nm was observed. The microthickness, surface morphology, and electrical conductivity of the printed substrate were then characterized by profilometer, atomic force microscope (AFM, and four-point probe electrical measurement, respectively. The inkjet deposition of PEDOT: PSS was successfully carried out, whilst retained its transparency feature. Highly smooth surface (roughness ~23–44 nm was achieved.

Influence of parenting style on the academic performance of middle school students

Directory of Open Access Journals (Sweden)

María José Domínguez

2014-06-01

Full Text Available Students who don't succeed in school are a persistent problem in our educational system. This fact shows that all the efforts to reduce this problem are not succeeding. One third of our students are left behind by the educational system; their results are discouraging. The measures to fight the academic failure are not working and that we have to put into practice new ways of analysis and treatment of this problem. This research explores the relationship between the way children perceive the parenting style of their parents and his o her own academic performance. In the intersection of both phenomena we find our hypothesis: the way parents socialise their children influences significantly on their academic performance. This research is orientated to decision taking process: the aim is to define the level of influence of the parenting style on academic outcomes. The main result is that parents acceptation/implication appears to be significantly linked to the school performance (this evidence shows a big area for new researches: the family. Our research confirms and frames the correlation between these two variables and underlies the family as a new scenario of pedagogical concern to explain and treat school failure.

Emotional Intelligence, Academic Procrastination and Academic ...

African Journals Online (AJOL)

Itwas therefore recommended that efforts should be made to look into other pressing factors like self-esteem, teacher's attitude, student's attitude, parental background among others which may be influencing student's poor academic achievement. Key words: Emotional Intelligence, Academic Procrastination, Academic ...

Career choice and its influence on academic performance of library ...

African Journals Online (AJOL)

The study examined career choice and its influence on academic performance of library and information science students in the University of Benin. Questionnaire was used to obtain information from the respondents. The entire population was used as sample because of the size of the population and the simple ...

Flexible white phosphorescent organic light emitting diodes based on multilayered graphene/PEDOT:PSS transparent conducting film

Energy Technology Data Exchange (ETDEWEB)

Wu, Xiaoxiao; Li, Fushan, E-mail: fushanli@hotmail.com; Wu, Wei; Guo, Tailiang, E-mail: gtl_fzu@hotmail.com

2014-03-01

Highlights: • A double-layered graphene/PEDOT:PSS film was fabricated by spray-coating. • A white flexible phosphorescent OLED was fabricated based on this film. • The white flexible OLED presented pure white light emission. • The flexible OLEDs showed a stable white emission during bending test. - Abstract: A double-layered graphene/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) conductive film was prepared, in which the PEDOT:PSS layer was obtained by using spray-coating technique. A flexible white phosphorescent organic light-emitting devices based on the graphene/PEDOT:PSS conductive film was fabricated. Phosphorescent material tris(2-phenylpyridine) iridium (Ir(ppy){sub 3}) and the fluorescent dye 5,6,11,12-tetraphenylnapthacene (Rubrene) were co-doped into 4,4′-N,N′-dicarbazole-biphenyl (CBP) host. N,N′-diphenyl-N,N′-bis(1-naphthyl)-(1,1′-biphenyl)-4,4′-diamine (NPB) and 4,7-diphenyl-1,10-phenanthroline (Bphen) were used as hole-transporting and electron-transporting layer, respectively, and 4,4′-bis(2,2′-diphenylvinyl)-1,1′-biphenyl (DPVBi) was used as blue light-emitting layer. The device presented pure white light emission with a Commission Internationale De I’Eclairage coordinates of (0.31, 0.33) and exhibited an excellent light-emitting stability during the bending cycle test with a radius of curvature of 10 mm.

Flexible white phosphorescent organic light emitting diodes based on multilayered graphene/PEDOT:PSS transparent conducting film

International Nuclear Information System (INIS)

Wu, Xiaoxiao; Li, Fushan; Wu, Wei; Guo, Tailiang

2014-01-01

Highlights: • A double-layered graphene/PEDOT:PSS film was fabricated by spray-coating. • A white flexible phosphorescent OLED was fabricated based on this film. • The white flexible OLED presented pure white light emission. • The flexible OLEDs showed a stable white emission during bending test. - Abstract: A double-layered graphene/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) conductive film was prepared, in which the PEDOT:PSS layer was obtained by using spray-coating technique. A flexible white phosphorescent organic light-emitting devices based on the graphene/PEDOT:PSS conductive film was fabricated. Phosphorescent material tris(2-phenylpyridine) iridium (Ir(ppy) 3 ) and the fluorescent dye 5,6,11,12-tetraphenylnapthacene (Rubrene) were co-doped into 4,4′-N,N′-dicarbazole-biphenyl (CBP) host. N,N′-diphenyl-N,N′-bis(1-naphthyl)-(1,1′-biphenyl)-4,4′-diamine (NPB) and 4,7-diphenyl-1,10-phenanthroline (Bphen) were used as hole-transporting and electron-transporting layer, respectively, and 4,4′-bis(2,2′-diphenylvinyl)-1,1′-biphenyl (DPVBi) was used as blue light-emitting layer. The device presented pure white light emission with a Commission Internationale De I’Eclairage coordinates of (0.31, 0.33) and exhibited an excellent light-emitting stability during the bending cycle test with a radius of curvature of 10 mm

Perceived Social Support and Early Adolescents' Achievement : The Mediational Roles of Motivational Beliefs and Emotions

NARCIS (Netherlands)

Ahmed, Wondimu; Minnaert, Alexander; van der Werf, Greetje; Kuyper, Hans

Although a bulk of literature shows that perceived social support (PSS) influences academic achievement, the mechanisms through which this effect operates received little empirical attention. The present study examined the multiple mediational effects of motivational beliefs (competence beliefs and

Graphene oxide/PEDOT:PSS composite hole transport layer for efficient and stable planar heterojunction perovskite solar cells.

Science.gov (United States)

Lee, Da-Young; Na, Seok-In; Kim, Seok-Soon

2016-01-21

We investigated a graphene oxide (GO)/poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) ( PSS) composite as a promising candidate for the practical application of a 2-D carbonaceous hole transport layer (HTL) to planar heterojunction perovskite solar cells (PeSCs) consisting of a transparent electrode/HTL/perovskite/fullerene/metal electrode. Both the insulating properties of GO and the non-uniform coating of the transparent electrode with GO cause the poor morphology of perovskite induced low power conversion efficiency (PCE) of 6.4%. On the other hand, PeSCs with a GO/PEDOT:PSS composite HTL, exhibited a higher PCE of 9.7% than that of a device fabricated with conventional PSS showing a PCE of 8.2%. The higher performance is attributed to the decreased series resistance (RS) and increased shunt resistance (RSh). The well-matched work-function between GO (4.9 eV) and PSS (5.1 eV) probably results in more efficient charge transport and an overall decrease in RS. The existence of GO with a large bandgap of ∼3.6 eV might induce the effective blocking of electrons, leading to an increase of RSh. Moreover, improvement in the long-term stability under atmospheric conditions was observed.

MnO2-Graphene Oxide-PEDOT:PSS Nanocomposite for an Electrochemical Supercapacitor

Science.gov (United States)

Patil, Dipali S.; Pawar, Sachin A.; Shin, Jae Cheol; Kim, Hyo Jin

2018-04-01

A ternary nanocomposite with poly (3,4 ethylene dioxythiophene:poly(styrene sulfonate) (PEDOT:PSS)-MnO2 nanowires-graphene oxide (PMn-GO) was synthesized by using simple chemical route. The formation of the nanocomposite was analyzed by using X-ray diffraction and X-ray photoelectron spectroscopy. Field-emission scanning microscopy (FESEM) revealed the formation of MnO2 nanowires and graphene oxide nanosheets. The highest specific capacitance (areal capacitance) of 841 Fg -1 (177 mFcm -2) at 10 mVs -1 and energy density of 0.593 kWhkg -1 at 0.5 mA were observed for PMn-GO, indicating a constructive synergistic effect of PEDOT:PSS, MnO2 nanowires and graphene oxide. The achieved promising electrochemical characteristics showed that this ternary nanocomposite is a good alternative as an electrode material for supercapacitor.

HSA/PSS coated gold nanorods as thermo-triggered drug delivery vehicles for combined cancer photothermal therapy and chemotherapy

Science.gov (United States)

Tu, Ting-Yu; Yang, Shu-Jyuan; Wang, Chung-Hao; Lee, Shin-Yu; Shieh, Ming-Jium

2018-02-01

Drug delivery systems combined multimodal therapy strategies are very promising in cancer theranostic applications. In this work, a new drug-delivery vehicles based on human serum albumin (HSA)-coated gold nanorods (GNR/PSS/HSA NPs) was developed. The success of coating was verified by transmission electron microscopy (TEM), zeta potential and fourier transform infrared spectroscopy (FTIR). Furthermore, it is demonstrated that doxorubicin (DOX) is successfully loaded among multilayered gold nanorods by the electrostatic and hydrophobic force, and DOX@GNR/PSS/HSA NPs were highly biocompatible and stable in various physiological solutions. The NPs possess strong absorbance in nearinfrared (NIR) region, and high photothermal conversion efficiency for outstanding photothermal therapy applications. A bimodal drug release triggered by proteinase or NIR irradiation has been revealed, resulting in a significant chemotherapeutic effect in tumor sites because of the preferential drug accumulation and triggered release. Importantly, the in vitro and in vivo experiments demonstrated that DOX@GNR/PSS/HSA NPs, which combined photothermal and chemotherapy for cancer therapy, revealing a remarkably superior synergistic anticancer effect over either monotherapy. All these results suggested a considerable potential of DOX@GNR/PSS/HSA NPs nano-platform for antitumor therapy.

Microtexturing of the conductive PEDOT:PSS Polymer for superhydrophobic organic electrochemical transistors

KAUST Repository

Gentile, Francesco; Coppedè , Nicola; Tarabella, Giuseppe; Villani, Marco; Calestani, Davide; Candeloro, Patrizio; Iannotta, Salvatore; Di Fabrizio, Enzo M.

2014-01-01

and materials science to obtain an advanced device where, on account of the superhydrophobicity of the system, the solutions of interest can be manipulated and, on account of the conductive PEDOT:PSS polymer, the charged molecules dispersed inside can

Students' Persistence and Academic Success in a First-Year Professional Bachelor Program: The Influence of Students' Learning Strategies and Academic Motivation

Directory of Open Access Journals (Sweden)

Gert Vanthournout

2012-01-01

Full Text Available The present study explores whether students' learning strategies and academic motivation predict persistence and academic success in the first year of higher education. Freshmen students in a professional bachelor program in teacher education were questioned on their learning strategy use and motivation at the start and at the end of the academic year. Students' learning strategies were assessed using the inventory of learning styles-SV. Motivation was measured using scales from the self-regulation questionnaire and the academic motivation scale. Gender and students' prior education were incorporated as control variables. Logistic regression analyses and general linear modelling were applied to predict persistence and academic success, respectively. In each case a stepwise approach in data analysis was used. Results on persistence indicate that lack of regulation and amotivation at the start of the year are significant predictors. For academic success, results showed that relating and structuring, lack of regulation, and lack of motivation at the end of the year are meaningful predictors. Overall, our study demonstrates that learning strategies and motivation have a moderate explanatory value regarding academic success and persistence, and that these effects remain even after controlling for the influence of background variables.

Energy level alignment at C{sub 60}/DTDCTB/PEDOT:PSS interfaces in organic photovoltaics

Energy Technology Data Exchange (ETDEWEB)

Yoo, Jisu; Jung, Kwanwook; Jeong, Junkyeong; Hyun, Gyeongho [Institute of Physics and Applied Physics, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722 (Korea, Republic of); Lee, Hyunbok, E-mail: hyunbok@kangwon.ac.kr [Department of Physics, Kangwon National University, Chuncheon-si, Gangwon-do 24341 (Korea, Republic of); Yi, Yeonjin, E-mail: yeonjin@yonsei.ac.kr [Institute of Physics and Applied Physics, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722 (Korea, Republic of)

2017-04-30

Highlights: • The interfacial energy level alignment of C{sub 60}/DTDCTB/PEDOT:PSS was determined via in situ UPS and IPES measurements. • A large photovoltaic gap of 1.30 eV was evaluated between the DTDCTB donor and C{sub 60} acceptor. • A low hole extraction barrier of 0.42 eV from DTDCTB to PEDOT:PSS was evaluated. • The excellent electronic properties of DTDCTB with a narrow band gap were the source of its high OPV power conversion efficiencies. - Abstract: The electronic structure of a narrow band gap small molecule ditolylaminothienyl–benzothiadiazole–dicyanovinylene (DTDCTB), possessing a donor-acceptor-acceptor configuration, was investigated with regard to its application as an efficient donor material in organic photovoltaics (OPVs). The interfacial orbital alignment of C{sub 60}/DTDCTB/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) was determined using in situ ultraviolet photoelectron and inverse photoelectron spectroscopic methods. The ionization energy and electron affinity values of DTDCTB were measured to be 5.27 eV and 3.65 eV, respectively, and thus a very small transport gap of 1.62 eV was evaluated. Large band bending of DTDCTB on PEDOT:PSS was observed, resulting in a low hole extraction barrier. Additionally, the photovoltaic gap between the highest occupied molecular orbital level of the DTDCTB donor and the lowest unoccupied molecular orbital level of the C{sub 60} acceptor was estimated to be 1.30 eV, which is known to be the theoretical maximum open-circuit voltage in OPVs employing the C{sub 60}/DTDCTB active layer. The unique electronic structures of DTDCTB contributed toward the recently reported excellent power conversion efficiencies of OPVs containing a DTDCTB donor material.

Photovoltaic performance of multi-wall carbon nanotube/PEDOT:PSS composite on the counter electrode of a dye-sensitized solar cell

Science.gov (United States)

Rhee, Yonghoon; Ko, Minjae; Jin, Hwayoung; Jin, Joon-Hyung; Min, Nam Ki

2014-08-01

A composite of poly(3,4-ethylendioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and multi-walled carbon nanotubes (MWCNTs) was cyclovoltametrically electropolymerized on a fluorine-doped tin oxide (FTO) substrate and used as a counter electrode for a dye-sensitized solar cell. The PEDOT:PSS-MWCNT composite film was investigated using scanning electron microscopy (SEM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The CV diagrams showed that the PEDOT:PSS-MWCNT composite film has better electro-catalytic activity for the I-/I3- redox reaction than the conventional platinized FTO. The best energy conversion efficiency was observed in EIS data with an MWCNT content of 0.002 wt %.

The Influence of Child Abuse on the Academic Performance of ...

African Journals Online (AJOL)

The aim of this study was to find out the influence of child abuse on pupils academic performance in primary science. To carry out this study effectively two variables were identified for the study. These were used to formulate the research hypotheses. The design for the study was ex-post-facto. The area of study was Cross ...

Trait procrastination among dental students in India and its influence on academic performance.

Science.gov (United States)

Madhan, Balasubramanian; Kumar, Cholleti Sudheer; Naik, Eslavath Seena; Panda, Sujit; Gayathri, Haritheertham; Barik, Ashish Kumar

2012-10-01

Trait procrastination is believed to be highly prevalent among college students and detrimental to their educational performance. As the scenario among dental students is virtually unknown, this study was conducted to evaluate the prevalence of trait procrastination among dental students and to analyze its influence on their academic performance. A total of 174 fourth-year dental students from three dental colleges in India voluntarily completed the Lay's Procrastination Scale-student version (LPS). The mean percentage marks scored in the subsequent final university examinations were used as a measure of academic performance. The descriptive statistics were computed to evaluate the prevalence of significant procrastination (LPS score ≥60). Mann-Whitney U test and multiple linear regressions were used to assess the influence of age and gender on procrastination severity, and the latter was again used to analyze the association between procrastination severity and academic performance. The results indicated that 27 percent (n=47) of the students exhibited a significant extent of trait procrastination; neither age nor gender affected its severity (pProcrastination had a significant and negative impact on the academic performance of the student (beta=-0.150, p=0.039). These findings highlight the need for active measures to reduce the causes and consequences of procrastination in dental education.

The Influence of Academic Culture on Quality Management System ISO 9001 Maintenance within Malaysian Universities

Science.gov (United States)

Basir, Siti Arni; Davies, John; Douglas, Jacqueline; Douglas, Alexander

2017-01-01

This study investigates the influence of the elements of academic culture on quality management system ISO 9001 maintenance within Malaysian universities. There is a dearth of empirical studies on maintaining ISO 9001, particularly in the higher education context. From the literature review, academic culture was classified according to four…

A Framework for PSS Business Models: Formalization and Application

OpenAIRE

Adrodegari, Federico; Saccani, Nicola; Kowalkowski, Christian

2016-01-01

In order to successfully move "from products to solutions", companies need to redesign their business model. Nevertheless, service oriented BMs in product-centric firms are under-investigated in the literature: very few works develop a scheme of analysis of such BMs. To provide a first step into closing this gap, we propose a new framework to describe service-oriented BMs, pointing out the main BM components and related PSS characteristics. Thus, the proposed framework aims to help companies ...

Analysis of the PEDOT:PSS/Si nanowire hybrid solar cell with a tail state model

Science.gov (United States)

Ho, Kuan-Ying; Li, Chi-Kang; Syu, Hong-Jhang; Lai, Yi; Lin, Ching-Fuh; Wu, Yuh-Renn

2016-12-01

In this paper, the electrical properties of the poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS)/silicon nanowire hybrid solar cell have been analyzed and an optimized structure is proposed. In addition, the planar PEDOT:PSS/c-Si hybrid solar cell is also modeled for comparison. We first developed a simulation software which is capable of modeling organic/inorganic hybrid solar cells by including Gaussian shape density of states into Poisson and drift-diffusion solver to present the tail states and trap states in the organic material. Therefore, the model can handle carrier transport, generation, and recombination in both organic and inorganic materials. Our results show that at the applied voltage near open-circuit voltage (Voc), the recombination rate becomes much higher at the PEDOT:PSS/Si interface region, which limits the fill factor and Voc. Hence, a modified structure with a p-type amorphous silicon (a-Si) layer attached on the interface of Si layer and an n+-type Si layer inserted near the bottom contact are proposed. The highest conversion efficiency of 16.10% can be achieved if both structures are applied.

Characterization of Piezoresistive PEDOT:PSS Pressure Sensors with Inter-Digitated and Cross-Point Electrode Structures

Directory of Open Access Journals (Sweden)

Jer-Chyi Wang

2015-01-01

Full Text Available The piezoresistive characteristics of poly(3,4-ethylenedioxythiophene:polystyrene sulfonate (PEDOT:PSS pressure sensors with inter-digitated (IDE and cross-point electrode (CPE structures have been investigated. A small variation of the resistance of the pressure sensors with IDE without bottom indium-tin-oxide (b-ITO film and with CPE structures was observed owing to the single carrier-conducting pathway. For the IDE pressure sensors with b-ITO, the piezoresistive characteristics at low and high pressure were similar to those of the pressure sensors with IDE without b-ITO and with CPE structures, respectively, leading to increased piezoresistive pressure sensitivity as the PEDOT:PSS film thickness decreased. A maximum sensitivity of more than 42 kΩ/Pa was achieved. When the normal pressure was applied, the increased number of conducting points or the reduced distance between the PEDOT oligomers within the PEDOT:PSS film resulted in a decrease of the resistance. The piezoresistive pressure sensors with a single carrier-conducting pathway, i.e., IDE without b-ITO and CPE structures, exhibited a small relaxation time and a superior reversible operation, which can be advantageous for fast piezoresistive response applications.

Characterization of piezoresistive PEDOT:PSS pressure sensors with inter-digitated and cross-point electrode structures.

Science.gov (United States)

Wang, Jer-Chyi; Karmakar, Rajat Subhra; Lu, Yu-Jen; Huang, Chiung-Yin; Wei, Kuo-Chen

2015-01-05

The piezoresistive characteristics of poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) pressure sensors with inter-digitated (IDE) and cross-point electrode (CPE) structures have been investigated. A small variation of the resistance of the pressure sensors with IDE without bottom indium-tin-oxide (b-ITO) film and with CPE structures was observed owing to the single carrier-conducting pathway. For the IDE pressure sensors with b-ITO, the piezoresistive characteristics at low and high pressure were similar to those of the pressure sensors with IDE without b-ITO and with CPE structures, respectively, leading to increased piezoresistive pressure sensitivity as the PEDOT:PSS film thickness decreased. A maximum sensitivity of more than 42 kΩ/Pa was achieved. When the normal pressure was applied, the increased number of conducting points or the reduced distance between the PEDOT oligomers within the PEDOT:PSS film resulted in a decrease of the resistance. The piezoresistive pressure sensors with a single carrier-conducting pathway, i.e., IDE without b-ITO and CPE structures, exhibited a small relaxation time and a superior reversible operation, which can be advantageous for fast piezoresistive response applications.

Book citations: influence of epidemiologic thought in the academic community

Directory of Open Access Journals (Sweden)

Porta Miquel

2006-01-01

Full Text Available Whilst their 'death' has often been certified, books remain highly important to most professions and academic disciplines. Analyses of citations received by epidemiologic texts may complement other views on epidemiology. The objective was to assess the number of citations received by some books of epidemiology and public health, as a first step towards studying the influence of epidemiological thought and thinking in academia. For this purpose, Institute for Scientific Information/ Thomson Scientific - Web of Science/ Web of Knowledgedatabase was consulted, in May 2006. The book by Rothman & Greenland appeared to have received the highest number of citations overall (over 8,000 and per year. The books by Kleinbaum et al, and by Breslow & Day received around 5,000 citations. In terms of citations per year the book by Sackett et al ranks 3rd, and the one by Rose, 4th of those included in this preliminary study. Other books which were influential in the classrooms collected comparatively less citations. Results offer a rich picture of the academic influences and trends of epidemiologic methods and reasoning on public health, clinical medicine and the other health, life and social sciences. They may contribute to assess epidemiologists' efforts to demarcate epidemiology and to assert epistemic authority, and to analyze some historical influences of economic, social and political forces on epidemiological research.

Who perceives they are smarter? Exploring the influence of student characteristics on student academic self-concept in physiology.

Science.gov (United States)

Cooper, Katelyn M; Krieg, Anna; Brownell, Sara E

2018-06-01

Academic self-concept is one's perception of his or her ability in an academic domain and is formed by comparing oneself to other students. As college biology classrooms transition from lecturing to active learning, students interact more with each other and are likely comparing themselves more to other students in the class. Student characteristics can impact students' academic self-concept; however, this has been unexplored in the context of undergraduate biology. In this study, we explored whether student characteristics can affect academic self-concept in the context of an active learning college physiology course. Using a survey, students self-reported how smart they perceived themselves to be in the context of physiology relative to the whole class and relative to their groupmate, the student with whom they worked most closely in class. Using linear regression, we found that men and native English speakers had significantly higher academic self-concept relative to the whole class compared with women and nonnative English speakers. Using logistic regression, we found that men had significantly higher academic self-concept relative to their groupmate compared with women. Using constant comparison methods, we identified nine factors that students reported influenced how they determined whether they were more or less smart than their groupmate. Finally, we found that students were more likely to report participating more than their groupmate if they had a higher academic self-concept. These findings suggest that student characteristics can influence students' academic self-concept, which in turn may influence their participation in small-group discussion and their academic achievement in active learning classes.

Composite films of oxidized multiwall carbon nanotube and poly(3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT:PSS) as a contact electrode for transistor and inverter devices.

Science.gov (United States)

Yun, Dong-Jin; Rhee, Shi-Woo

2012-02-01

Composite films of multiwall carbon nanotube (MWNT)/poly(3,4-ethylenedioxythiophene) polymerized with poly(4-styrenesulfonate) (PEDOT:PSS) were prepared by spin-coating a mixture solution. The effect of the MWNT loading and the MWNT oxidation, with acid solution or ultraviolet (UV)-ozone treatment, on the film properties such as surface roughness, work function, surface energy, optical transparency and conductivity were studied. Also pentacene thin film transistors and inverters were made with these composite films as a contact metal and the device characteristics were measured. The oxidation of MWNT reduced the conductivity of MWNT/PEDOT:PSS composite film but increased the work function and transparency. UV-ozone treated MWNT/PEDOT:PSS composite film showed higher conductivity (14000 Ω/□) and work function (4.9 eV) than acid-oxidized MWNT/PEDOT:PSS composite film and showed better performance as a source/drain electrode in organic thin film transistor (OTFT) than other types of MWNT/PEDOT:PSS composite films. Hole injection barrier of the UV-ozone treated MWNT/PEDOT:PSS composite film with pentacene was significantly lower than any other films because of the higher work function.

A Qualitative Study of the Influences on Clinical Academic Physicians' Postdoctoral Career Decision-Making.

Science.gov (United States)

Ranieri, Veronica F; Barratt, Helen; Rees, Geraint; Fulop, Naomi J

2018-01-23

To describe the influences on clinical academic physicians' postdoctoral career decision-making. Thirty-five doctoral trainee physicians from University College London took part in semi-structured interviews in 2015 and 2016. Participants were asked open-ended questions about their career to-date, their experiences undertaking a PhD, and their career plans post-PhD. The interviews were audio-recorded and transcribed. Thematic analysis was used to generate, review, and define themes from the transcripts. Emerging differences and similarities in participants' reasons for pursuing a PhD were then grouped to produce typologies to explore how their experiences influenced their career decision-making. Participants described four key reasons for undertaking a PhD, which formed the basis of the four typologies identified. These reasons included: to pursue a clinical academic career; to complete an extensive period of research to understand whether a clinical academic career was the desired path forward; to improve clinical career prospects; and to take a break from clinical training. These findings highlight the need to target efforts at retaining clinical academic physicians according to their reasons for pursuing a PhD and their subsequent experiences with the process. Those responsible for overseeing clinical training must be well-informed of the long-term benefits of training academically-qualified physicians. In light of current political uncertainty, universities, hospitals, and external agencies alike must increase their efforts to inspire and assuage early-career clinical academic physicians' fears regarding their academic future.This is an open access article distributed under the Creative Commons Attribution License 4.0 (CCBY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Influence of Mothers' Parenting Styles on Self-Regulated Academic Learning among Saudi Primary School Students

Science.gov (United States)

Alnafea, Tahany; Curtis, David D.

2017-01-01

Much of the research on self-regulation has investigated the influence of school settings. However, fewer studies have concentrated on the home environment and its influence on student's academic behaviour in school. The present research investigates the influence of mothers' parenting styles on students' self-regulated learning behaviours in…

Rear-Sided Passivation by SiNx:H Dielectric Layer for Improved Si/PEDOT:PSS Hybrid Heterojunction Solar Cells.

Science.gov (United States)

Sun, Yiling; Gao, Pingqi; He, Jian; Zhou, Suqiong; Ying, Zhiqin; Yang, Xi; Xiang, Yong; Ye, Jichun

2016-12-01

Silicon/organic hybrid solar cells have recently attracted great attention because they combine the advantages of silicon (Si) and the organic cells. In this study, we added a patterned passivation layer of silicon nitride (SiNx:H) onto the rear surface of the Si substrate in a Si/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) ( PSS) hybrid solar cell, enabling an improvement of 0.6 % in the power conversion efficiency (PCE). The addition of the SiNx:H layer boosted the open circuit voltage (V oc) from 0.523 to 0.557 V, suggesting the well-passivation property of the patterned SiNx:H thin layer that was created by plasma-enhanced chemical vapor deposition and lithography processes. The passivation properties that stemmed from front PSS, rear-SiNx:H, front PSS/rear-SiNx:H, etc. are thoroughly investigated, in consideration of the process-related variations.

Surface analysis of the selective excimer laser patterning of a thin PEDOT:PSS film on flexible polymer films

Science.gov (United States)

Schaubroeck, David; De Smet, Jelle; Willems, Wouter; Cools, Pieter; De Geyter, Nathalie; Morent, Rino; De Smet, Herbert; Van Steenbeerge, Geert

2016-07-01

Fast patterning of highly conductive polymers like PEDOT:PSS (poly (3,4-ethylene dioxythiophene): polystyrene sulfonate) with lasers can contribute to the development of industrial production of liquid crystal displays on polymer foils. In this article, the selective UV laser patterning of a PEDOT:PSS film on flexible polymer films is investigated. Based on their optical properties, three polymer films are investigated: polyethylene terephthalate (PET), polymethyl methacrylate (PMMA) and cellulose triacetate (TAC). Ablation parameters for a 110 nm PEDOT:PSS film on these polymer films are optimized. A detailed study of the crater depth, topography and surface composition are provided using optical profilometry, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), respectively. The electrical insulation of the lines is measured and correlated to the crater analyses for different laser settings. Finally, potential ablation parameters for each of the polymer films are derived.

Factors that influence career progression among postdoctoral clinical academics: a scoping review of the literature

Science.gov (United States)

Ranieri, Veronica; Barratt, Helen; Fulop, Naomi; Rees, Geraint

2016-01-01

Background The future of academic medicine is uncertain. Concerns regarding the future availability of qualified and willing trainee clinical academics have been raised worldwide. Of significant concern is our failure to retain postdoctoral trainee clinical academics, who are likely to be our next generation of leaders in scientific discovery. Objectives To review the literature about factors that may influence postdoctoral career progression in early career clinical academics. Design This study employed a scoping review method. Three reviewers separately assessed whether the articles found fit the inclusion criteria. Data sources PubMed, Scopus, Web of Science and Google Scholar (1991–2015). Article selection The review encompassed a broad search of English language studies published anytime up to November 2015. All articles were eligible for inclusion, including research papers employing either quantitative or qualitative methods, as well as editorials and other summary articles. Data extraction Data extracted from included publications were charted according to author(s), sample population, study design, key findings, country of origin and year of publication. Results Our review identified 6 key influences: intrinsic motivation, work–life balance, inclusiveness, work environment, mentorship and availability of funding. It also detected significant gaps within the literature about these influences. Conclusions Three key steps are proposed to help support postdoctoral trainee clinical academics. These focus on ensuring that researchers feel encouraged in their workplace, involved in collaborative dialogue with key stakeholders and able to access reliable information regarding their chosen career pathway. Finally, we highlight recommendations for future research. PMID:27798036

Academic Stress Influences Periodontal Health Condition and Interleukin-1 beta Level

Directory of Open Access Journals (Sweden)

Sandra O. Kuswandani

2014-10-01

Full Text Available Stress is a risk factor for periodontal disease, causing increase levels of interleukin-1 beta that involve in periodontal destruction. Objective: To analyze the relationship between academic stress in residency program students conditions and levels of interleukin-1 beta in gingival crevicular fluid. Methods: Thirty eight subjects filled the questionnaire of Graduate Dental Environtmental Stress (GDES, periodontal examination and samples of gingival crevicular fluid were tested for interleukin-1 beta with the Enzyme-linked Immunosorbent Assay (ELISA test. Results: There were significant differences between academic stress to periodontal tissue in oral hygiene (p=0.038, bleeding on probing index (p=0.02, but no significant differences in pocket depth and loss of attachment (p=0.972. There were significant differences between academic stress to levels of interleukin-1 beta (p=0.03, but no significant differences between levels of interleukin-1 beta to periodontal tissue in oral hygiene (p=0.465, bleeding on probing index (p=0.826, pocket depth (p=0.968, and loss of attachment (p=0.968. Conclusion: Academic stress influences the periodontal risk factor and level of interleukin-1 beta.

Layered sulfur/PEDOT:PSS nano composite electrodes for lithium sulfur cell applications

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Anilkumar, K. M.; Jinisha, B.; Manoj, M.; Pradeep, V. S.; Jayalekshmi, S.

2018-06-01

Lithium-Sulfur (Li-S) cells are emerging as the next generation energy storage devices owing to their impressive electrochemical properties with high theoretical specific capacity of 1675 mAh/g. Lack of electronic conductivity of sulfur, its volume expansion during high lithium intake and the shuttling effect due to the formation of soluble polysulfides are the main limitations, delaying the commercialization of this technology. To address these challenges, in the present work, the conducting polymer PEDOT:PSS is used as the covering matrix over the sulfur particles to improve their Li storage properties. The sulfur/PEDOT:PSS nanocomposite is synthesised using the hydrothermal process and its formation with the polymer coating over sulfur nanoparticles is established from the XRD, Raman spectroscopy, FE-SEM and TEM studies. The electrochemical studies show that the cells assembled using the sulfur/PEDOT:PSS nanocomposite as the cathode, with the components taken in the weight ratio of 9:1, offer a reversible capacity of 1191 mAh g-1 at 0.1C rate. These cells display stable electrochemical capacities over 200 cycles at gradually increasing current rates. The polymer layer facilitates electronic conduction and suppresses the polysulfide formation and the volume expansion of sulfur. A reversible capacity of 664 mAh g-1 is observed after 200 cycles at 1C rate with the capacity retention of 75 % of the initial stable capacity. The highlight of the present work is the possibility to achieve high discharge capacities at high C rates and the retention of a good percentage of the initial capacity over 200 cycles, for these Li-S cells.

Possible Major Influences of Children Learning Social Studies on Academic Self Concept and Achievement

Directory of Open Access Journals (Sweden)

Laurens Kaluge

2016-02-01

Full Text Available This study was aimed at finding the best model to explain pupil academic attainment in learning social studies. The data came from pupils learning Social Studies at grade 3 and 4 of primary schools. The structural equation model contained 2 exogenous constructs–attitudes toward school and locus of control–and 2 endogenous constructs–self-concept and academic achievement. It was confirmed that the academic self-concept and achievement related to each other and both were influenced by attitudes toward school and internal locus of control. The model was fitting differently for different grade.

Silver Nanowires Modified with PEDOT: PSS and Graphene for Organic Light-Emitting Diodes Anode.

Science.gov (United States)

Xu, Yilin; Wei, Xiang; Wang, Cong; Cao, Jin; Chen, Yigang; Ma, Zhongquan; You, Ying; Wan, Jixiang; Fang, Xiaohong; Chen, Xiaoyuan

2017-03-28

Silver nanowires (AgNWs) networks are promising candidates for the replacement of indium tin oxide (ITO). However, the surface roughness of the AgNWs network is still too high for its application in optoelectronic devices. In this work, we have reduced the surface roughness of the AgNWs networks to 6.4 nm, compared to 33.9 nm of the as-deposited AgNWs network through the hot-pressing process, treatment with poly (3,4ethylenedioxythiophene)-poly (styrenesulfanate), and covered with graphene films. Using this method, we are able to produce AgNWs/PEDOT: PSS/SLG composite films with the transmittance and sheet resistance of 88.29% and 30 Ω/□, respectively. The OLEDs based on the AgNWs/PEDOT: PSS/SLG anodes are comparable to those based on ITO anodes.

Heuristic method of fabricating counter electrodes in dye-sensitized solar cells based on a PEDOT:PSS layer as a catalytic material

International Nuclear Information System (INIS)

Edalati, Sh; Houshangi far, A; Torabi, N; Baneshi, Z; Behjat, A

2017-01-01

Poly(3,4-ethylendioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) was deposited on a fluoride-doped tin oxide glass substrate using a heuristic method to fabricate platinum-free counter electrodes for dye-sensitized solar cells (DSSCs). In this heuristic method a thin layer of PEDOT:PPS is obtained by spin coating the PEDOT:PSS on a Cu substrate and then removing the substrate with FeCl 3 . The characteristics of the deposited PEDOT:PSS were studied by energy dispersive x-ray analysis and scanning electron microscopy, which revealed the micro-electronic specifications of the cathode. The aforementioned DSSCs exhibited a solar conversion efficiency of 3.90%, which is far higher than that of DSSCs with pure PEDOT:PSS (1.89%). This enhancement is attributed not only to the micro-electronic specifications but also to the HNO 3 treatment through our heuristic method. The results of cyclic voltammetry, electrochemical impedance spectroscopy (EIS) and Tafel polarization plots show the modified cathode has a dual function, including excellent conductivity and electrocatalytic activity for iodine reduction. (paper)

PEDOT:PSS interfaces support the development of neuronal synaptic networks with reduced neuroglia response in vitro

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Giada eCellot

2016-01-01

Full Text Available The design of electrodes based on conductive polymers in brain-machine interface technology offers the opportunity to exploit variably manufactured materials to reduce gliosis, indeed the most common brain response to chronically implanted neural electrodes. In fact, the use of conductive polymers, finely tailored in their physical-chemical properties, might result in electrodes with improved adaptability to the brain tissue and increased charge-transfer efficiency. Here we interfaced poly(3,4-ethylenedioxythiophene:poly(styrene sulfonate (PEDOT:PSS doped with different amounts of ethylene glycol (EG with rat hippocampal primary cultures grown for 3 weeks on these synthetic substrates. We used immunofluorescence and scanning electron microscopy combined to single cell electrophysiology to assess the biocompatibility of PEDOT:PSS in terms of neuronal growth and synapse formation. We investigated neuronal morphology, density and electrical activity. We reported the novel observation that opposite to neurons, glial cell density was progressively reduced, hinting at the ability of this material to down regulate glial reaction. Thus PEDOT:PSS is an attractive candidate for the design of new implantable electrodes, controlling the extent of glial reactivity without affecting neuronal viability and function.

The Influence of MCAT and GPA Preadmission Academic Metrics on Interview Scores

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Gay, Steven E.; Santen, Sally A.; Mangrulkar, Rajesh S.; Sisson, Thomas H.; Ross, Paula T.; Zaidi, Nikki L. Bibler

2018-01-01

Medical school admissions interviews are used to assess applicants' nonacademic characteristics as advocated by the Association of American Medical Colleges' Advancing Holistic Review Initiative. The objective of this study is to determine whether academic metrics continue to significantly influence interviewers' scores in holistic processes by…

Factors that influence career progression among postdoctoral clinical academics: a scoping review of the literature.

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Ranieri, Veronica; Barratt, Helen; Fulop, Naomi; Rees, Geraint

2016-10-21

The future of academic medicine is uncertain. Concerns regarding the future availability of qualified and willing trainee clinical academics have been raised worldwide. Of significant concern is our failure to retain postdoctoral trainee clinical academics, who are likely to be our next generation of leaders in scientific discovery. To review the literature about factors that may influence postdoctoral career progression in early career clinical academics. This study employed a scoping review method. Three reviewers separately assessed whether the articles found fit the inclusion criteria. PubMed, Scopus, Web of Science and Google Scholar (1991-2015). The review encompassed a broad search of English language studies published anytime up to November 2015. All articles were eligible for inclusion, including research papers employing either quantitative or qualitative methods, as well as editorials and other summary articles. Data extracted from included publications were charted according to author(s), sample population, study design, key findings, country of origin and year of publication. Our review identified 6 key influences: intrinsic motivation, work-life balance, inclusiveness, work environment, mentorship and availability of funding. It also detected significant gaps within the literature about these influences. Three key steps are proposed to help support postdoctoral trainee clinical academics. These focus on ensuring that researchers feel encouraged in their workplace, involved in collaborative dialogue with key stakeholders and able to access reliable information regarding their chosen career pathway. Finally, we highlight recommendations for future research. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Does Self-Citation Influence Quantitative Measures of Research Productivity Among Academic Oral and Maxillofacial Surgeons?

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Susarla, Srinivas M; Swanson, Edward W; Lopez, Joseph; Peacock, Zachary S; Dodson, Thomas B

2015-10-01

Quantitative measures of research productivity depend on the citation frequency of a publication. Citation-based metrics, such as the h-index (total number of publications h that have at least h citations), can be susceptible to self-citation, resulting in an inflated measure of research productivity. The purpose of the present study was to estimate the effect of self-citation on the h-index among academic oral and maxillofacial surgeons (OMSs). The present study was a cross-sectional study of full-time academic OMSs in the United States. The predictor variable was the frequency of self-citation. The primary outcome of interest was the h-index. Other study variables included demographic factors and citation metrics. Descriptive, bivariate, and regression statistics were computed. The study sample consisted of 325 full-time academic OMSs. Most surgeons were men (88.3%); approximately 40% had medical degrees. The study subjects had an average of 23.5 ± 37.1 publications. The mean number of self-citations was 15 + 56. The sample's mean h-index was 6.6 ± 7.6 and was associated with self-citation (r = 0.71, P citations. After adjusting for PhD degree, total number of publications, and academic rank, an increasing self-citation rate influenced the h-index (r = 0.006, P citations were more likely to have their h-index influenced by self-citation. Self-citation among full-time academic OMSs does not substantially affect the h-index. Surgeons in the top quartile of self-citation rates are more likely to influence their h-index. Copyright © 2015 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Relationships between molecular structure and kinetic and thermodynamic controls in lipid systems. Part III. Crystallization and phase behavior of 1-palmitoyl-2,3-stearoyl-sn-glycerol (PSS) and tristearoylglycerol (SSS) binary system.

Science.gov (United States)

Bouzidi, Laziz; Narine, Suresh S

2012-01-01

The phase behavior of 1-palmitoyl-2,3-distearoyl-sn-glycerol (PSS)/tristearoylglycerol (SSS) binary system was investigated in terms of polymorphism, crystallization and melting behavior, microstructure and solid fat content (SFC) using widely different constant cooling rates. Kinetic phase diagrams were experimentally determined from the DSC heating thermograms and analyzed using a thermodynamic model to account for non-ideality of mixing. The kinetic phase diagram presented a typical eutectic behavior with a eutectic point at the 0.5(PSS) mixture with a probable precipitation line from 0.5(PSS) to 1.0(PSS), regardless of the rate at which the sample was cooled. The eutectic temperature decreased only slightly with increasing cooling rate. PSS has a strong effect on the physical properties of the PSS-SSS mixtures. In fact, the overall phase behavior of the PSS-SSS binary system was determined, for a very large part, by the asymmetrical TAG. Moreover, PSS is a key driver of the high stability observed in crystal growth, polymorphism and phase development. Levels as low as 10% PSS, when cooled slowly, and 30% when cooled rapidly, were found to be sufficient to suppress the effect of thermal processing. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

The Roll of NaPSS Surfactant on the Ceria Nanoparticles Embedding in Polypyrrole Films

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Simona Popescu

2016-01-01

Full Text Available Cerium oxide nanoparticles (CeO2 NPs in crystalline form have been synthesized by a coprecipitation method. CeO2 nanoparticles were then embedded in polypyrrole (PPy films during the electropolymerization of pyrrole (Py on titanium substrate. The influence of poly(sodium 4-styrenesulfonate (NaPSS surfactant used during polymerization on the embedding of CeO2 NPs in polypyrrole films was investigated. The new films were characterized in terms of surface analysis, wettability, electrochemical behaviour, and antibacterial effect. The surface and electrochemical characterization revealed the role of surfactant on PPy doping process cerium oxide incorporation. In the presence of surfactant, CeO2 NPs are preferentially embedded in the polymeric film while, without surfactant, the ceria nanoparticles are quasiuniformly spread as agglomerates onto polymeric films. The antibacterial effect of studied PPy films was substantially improved in the presence of cerium oxide and depends by the polymerization conditions.

Assessment of academic/non-academic factors and extracurricular activities influencing performance of medical students of faculty of medicine, Universiti Sultan Zainal Abidin, Malaysia

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Mainul Haque

2018-01-01

Full Text Available Background: Physical and mental comfort is known to have a crucial influence on health and performance amongst medical students. Very often, medical students suffer from poor quality of life (QOL related to the work-life balance due to the lack of sleep, nutritional and dietary disorders and low physical activity, resulting in a negative impact on their academic performance. This study aims to determine the potential academic/non-academic factors and extra-curricular activities influencing the performance of medical students in Universiti Sultan Zainal Abidin (UniSZA. Materials and Methods: This was a cross-sectional study conducted on medical students at the Faculty of Medicine, UniSZA, Terengganu, Malaysia. A sample size of 300 respondents were recruited from Year I to V medical students. The questionnaire was adopted, modified and validated from a similar study in Saudi Arabia. Results: Majority of the students enjoy medical education are self-motivated, have a good command of English, non-smokers and have a sufficient sleep. Conclusion: University medical students possess good QOL within the optimum educational environment.

The Critical Choice of PEDOT: PSS Additives for Long Term Stability of Roll‐to‐Roll Processed OPVs

DEFF Research Database (Denmark)

Roth, Bérenger; Benatto, Gisele Alves dos Reis; Corazza, Michael

2015-01-01

The impact of additives mixed with poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) on the stability of organic photovoltaic modules is investigated for fully ambient roll-to-roll (R2R) processed indium tin oxide free modules. Four different PEDOT:PSS inks from two different...... on organic photovoltaic stability (ISOS). For the harsh indoor test (ISOS-L-3) only a slight difference in stability is observed between the different modules. During both ISOS-L-3 and ISOS-D-3 one new failure mode is observed as a result of tiny air inclusions in the barrier foil and a R2R method...

The Role of Academic Self-Efficacy as a Mediator Variable between Perceived Academic Climate and Academic Performance

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Abd-Elmotaleb, Moustafa; Saha, Sudhir K.

2013-01-01

This study examines the mediating influence of academic self-efficacy on the link between perceived academic climate and academic performance among university students. The participants in the study consist of 272 undergraduate students at the University of Assiut, Assiut, Egypt. A scale to measure perceived academic climate, was developed. To…

Performance and Long-Term Stability of Pd/PSS and Pd/Al2O3 Membranes for Hydrogen Separation.

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Liguori, Simona; Iulianelli, Adolfo; Dalena, Francesco; Pinacci, Pietro; Drago, Francesca; Broglia, Maria; Huang, Yan; Basile, Angelo

2014-03-06

The present work is focused on the investigation of the performance and long-term stability of two composite palladium membranes under different operating conditions. One membrane (Pd/porous stainless steel (PSS)) is characterized by a ~10 µm-thick palladium layer on a porous stainless steel substrate, which is pretreated by means of surface modification and oxidation; the other membrane (Pd/Al2O3) is constituted by a ~7 µm-thick palladium layer on an asymmetric microporous Al2O3 substrate. The operating temperature and pressure ranges, used for studying the performance of these two kinds of membranes, are 350-450 °C and 200-800 kPa, respectively. The H2 permeances and the H2/N2 selectivities of both membranes were investigated and compared with literature data. At 400 °C and 200 kPa as pressure difference, Pd/PSS and Pd/Al2O3 membranes exhibited an H2/N2 ideal selectivity equal to 11700 and 6200, respectively, showing stability for 600 h. Thereafter, H2/N2 selectivity of both membranes progressively decreased and after around 2000 h, dropped dramatically to 55 and 310 for the Pd/PSS and Pd/Al2O3 membranes, respectively. As evidenced by Scanning Electron Microscope (SEM) analyses, the pinholes appear on the whole surface of the Pd/PSS membrane and this is probably due to release of sulphur from the graphite seal rings.

Polymeric Flexible Immunosensor Based on Piezoresistive Micro-Cantilever with PEDOT/PSS Conductive Layer

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Rui Zhao

2018-02-01

Full Text Available In this paper, a fully polymeric micro-cantilever with the surface passivation layer of parylene-C and the strain resistor of poly(3,4-ethylenedioxythiophene/poly (styrene sulfonate (PEDOT/PSS was proposed and demonstrated for immunoassays. By optimizing the design and fabrication of the polymeric micro-cantilever, a square resistance of 220 Ω/□ for PEDOT/PSS conductive layer have been obtained. The experimental spring constant and the deflection sensitivity were measured to be 0.017 N/m and 8.59 × 10−7 nm−1, respectively. The biological sensing performances of polymeric micro-cantilever were investigated by the immunoassay for human immunoglobulin G (IgG. The immunosensor was experimentally demonstrated to have a linear behavior for the detection of IgG within the concentrations of 10~100 ng/mL with a limit of detection (LOD of 10 ng/mL. The experimental results indicate that the proposed polymeric flexible conductive layer-based sensors are capable of detecting trace biological substances.

Polymeric Flexible Immunosensor Based on Piezoresistive Micro-Cantilever with PEDOT/PSS Conductive Layer.

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Zhao, Rui; Sun, Ying

2018-02-03

In this paper, a fully polymeric micro-cantilever with the surface passivation layer of parylene-C and the strain resistor of poly(3,4-ethylenedioxythiophene)/poly (styrene sulfonate) (PEDOT/PSS) was proposed and demonstrated for immunoassays. By optimizing the design and fabrication of the polymeric micro-cantilever, a square resistance of 220 Ω/□ for PEDOT/PSS conductive layer have been obtained. The experimental spring constant and the deflection sensitivity were measured to be 0.017 N/m and 8.59 × 10 -7 nm -1 , respectively. The biological sensing performances of polymeric micro-cantilever were investigated by the immunoassay for human immunoglobulin G (IgG). The immunosensor was experimentally demonstrated to have a linear behavior for the detection of IgG within the concentrations of 10~100 ng/mL with a limit of detection (LOD) of 10 ng/mL. The experimental results indicate that the proposed polymeric flexible conductive layer-based sensors are capable of detecting trace biological substances.

Peer Influence on Academic Performance: A Social Network Analysis of Social-Emotional Intervention Effects.

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DeLay, Dawn; Zhang, Linlin; Hanish, Laura D; Miller, Cindy F; Fabes, Richard A; Martin, Carol Lynn; Kochel, Karen P; Updegraff, Kimberly A

2016-11-01

Longitudinal social network analysis (SNA) was used to examine how a social-emotional learning (SEL) intervention may be associated with peer socialization on academic performance. Fifth graders (N = 631; 48 % girls; 9 to 12 years) were recruited from six elementary schools. Intervention classrooms (14) received a relationship building intervention (RBI) and control classrooms (8) received elementary school as usual. At pre- and post-test, students nominated their friends, and teachers completed assessments of students' writing and math performance. The results of longitudinal SNA suggested that the RBI was associated with friend selection and peer influence within the classroom peer network. Friendship choices were significantly more diverse (i.e., less evidence of social segregation as a function of ethnicity and academic ability) in intervention compared to control classrooms, and peer influence on improved writing and math performance was observed in RBI but not control classrooms. The current findings provide initial evidence that SEL interventions may change social processes in a classroom peer network and may break down barriers of social segregation and improve academic performance.

Academic Achievement, Perceived Stress, Admission Data, and Sociodemographic Background Among Therapy Students in Israel.

Science.gov (United States)

Jacob, Tamar; Einstein, Ofira

2017-01-01

Academic achievement (AA) is of great importance in the academic world. The aims of this study were to: 1) identify contributors to AA of physical therapy (PT) students; 2) evaluate students' perceived stress (PS); and 3) identify contributors to PS. A cross-sectional study involving three undergraduate PT classes in a single academic year was performed 1 week prior to final examinations. Current grade point average (GPA) and admission data were collected from administrative records. Additional data, collected using an online questionnaire, included the Perceived Stress Scale 10 (PSS), Scale for Assessing Academic Stress (SAAS), and selected sociodemographic variables. Regression analysis identified contributors to AA and to PS. Records of 153 students and questionnaires of 118 students were included in the study. Combined grades from psychometric tests and matriculation exams at admission, low PS, absence due to military reserve service during the academic year, and participation in the second and third years of the PT program accounted for a modest variance (31.1% ) in students' GPA. The low contribution of admission criteria to GPA suggests that there is no justification for raising the level of the present criteria.

The Malay Version of the Perceived Stress Scale (PSS)-10 is a Reliable and Valid Measure for Stress among Nurses in Malaysia.

Science.gov (United States)

Sandhu, Sukhvinder Singh; Ismail, Noor Hassim; Rampal, Krishna Gopal

2015-11-01

The Perceived Stress Scale-10 (PSS-10) is widely used to assess stress perception. The aim of this study was to translate the original PSS-10 into Malay and assess the reliability and validity of the Malay version among nurses. The Malay version of the PSS-10 was distributed among 229 nurses from four government hospitals in Selangor State. Test-retest reliability and concurrent validity was conducted with 25 nurses with the Malay version of the Depression Anxiety Stress Scales (DASS) 21. Cronbach's alpha, confirmatory factor analysis (CFA), intraclass correlation coefficient and Pearson's r correlation coefficient were used to determine the psychometric properties of the Malay PSS-10. Two factor components were yielded through exploratory factor analysis with eigenvalues of 3.37 and 2.10, respectively. Both of the factors accounted for 54.6% of the variance. CFA yielded a two-factor structure with satisfactory goodness-of-fit indices [x 2 /df = 2.43; comparative fit index (CFI) = 0.92, goodness-of-fit Index (GFI) = 0.94; standardised root mean square residual (SRMR) = 0.07 and root mean square error of approximation (RMSEA) = 0.08 (90% CI = 0.07-0.09)]. The Cronbach's alpha coefficient for the total items was 0.63 (0.82 for factor 1 and 0.72 for factor 2). The intraclass correlation coefficient (ICC) was 0.81 (95% CI: 0.62-0.91) for test-retest reliability testing after seven days. The total score and the negative component of the PSS-10 correlated significantly with the stress component of the DASS-21: (r = 0.61, P < 0.001) and (r = 0.56, P < 0.004), respectively. The Malay version of the PSS-10 demonstrated a satisfactory level of validity and reliability to assess stress perception. Therefore, this questionnaire is valid in assessing stress perception among nurses in Malaysia.

Reversing an S-kink effect caused by interface degradation in organic solar cells through gold ion implantation in the PEDOT:PSS layer

Science.gov (United States)

Brenes-Badilla, D.; Coutinho, D. J.; Amorim, D. R. B.; Faria, R. M.; Salvadori, M. C.

2018-04-01

In this work, we performed a study on the recovery of the photovoltaic performance of an ITO/PEDOT:PSS/P3HT:PCBM/Ca/Al solar cell after the hole transport layer (PEDOT:PSS) had been degraded by contact with the environment. A device that was fully built in an inert environment exhibited a fill factor (FF) of 0.64, while the device whose hole transport layer was exposed to air presented a FF equal to 0.2. In addition, the J-V characteristic curve of the degraded device did not follow the photovoltaic pattern exhibiting the degenerate S shape. However, the elimination of the deleterious effect was achieved by bombarding gold ions on the contaminated surface of PEDOT:PSS by means of the Metal Plasma Immersion Ion Implantation technique. Due to the low energy of the ionic beam of gold, the implanted gold atoms were located at few nanometers off the surface, forming nanometric clusters, that is, gold nanoparticles. Most probably, the degradation of the J-V photovoltaic curve, represented by the S-kink effect, was caused by the appearance of a potential barrier at PEDOT:PSS/P3HT:PCBM interface, which was demolished by the gold nanoparticles that have work function close to HOMO of P3HT. This S-kink effect was also simulated by using an equivalent circuit model constituted by a two-diode circuit, one of which plays the role of the undesirable potential barrier formed at the PEDOT:PSS/P3HT:PCBM interface. Our analysis shows that deposition of gold nanoparticles next to the interface recovers the good hole injection condition from the PEDOT:PSS into the active layer, restoring the fill factor and the device efficiency.

Hybrid UV-Ozone-Treated rGO-PEDOT:PSS as an Efficient Hole Transport Material in Inverted Planar Perovskite Solar Cells

Science.gov (United States)

Wang, Shuying; Huang, Xiaona; Sun, Haoxuan; Wu, Chunyang

2017-12-01

Inverted planar perovskite solar cells (PSCs), which are regarded as promising devices for new generation of photovoltaic systems, show many advantages, such as low-temperature film formation, low-cost fabrication, and smaller hysteresis compared with those of traditional n-i-p PSCs. As an important carrier transport layer in PSCs, the hole transport layer (HTL) considerably affects the device performance. Therefore, HTL modification becomes one of the most critical issues in improving the performance of PSCs. In this paper, we report an effective and environmentally friendly UV-ozone treatment method to enhance the hydrophilia of reduced graphene oxide (rGO) with its excellent electrical performance. The treated rGO was applied to doped poly(3,4-ethylenedioxythiophene) poly(styrene-sulfonate) (PEDOT:PSS) as HTL material of PSCs. Consequently, the performance of rGO/PEDOT:PSS-doped PSCs was improved significantly, with power conversion efficiency (PCE) of 10.7%, Jsc of 16.75 mA/cm2, Voc of 0.87 V, and FF of 75%. The PCE of this doped PSCs was 27% higher than that of the PSCs with pristine PEDOT:PSS as HTL. This performance was attributed to the excellent surface morphology and optimized hole mobility of the solution-processable rGO-modified PEDOT:PSS.

Unveiling Research Agendas: a study of the influences on research problem selection among academic researchers

Energy Technology Data Exchange (ETDEWEB)

Bianco, M.; Sutz, J.

2016-07-01

Research problem selection is central to the dynamics of scientific knowledge production. Research agendas result from the selection of research problems and the formulation of individual and/or collective academic strategies to address them. But, why researchers study what they study? This paper presents incipient research focused on the way different factors influence the construction of academic research agendas. It takes a researcher-oriented approach relying on opinions and perspectives of a wide range of researchers in all fields of knowledge. The empirical work is carried out in Uruguay, a country in the periphery of mainstream science, whose academic community struggles in search of a balance between the requirements of the world community of scholars and the demands from different national stakeholders. The methodology and research results from this study may be relevant to other countries, at different peripheries. Further, understanding the interplay of influences that shape research agendas is an important tool for policy analysis and planning everywhere. (Author)

Workplace Influences on Chinese TEFL Academics' Development as Researchers: A Study of Two Chinese Higher Education Institutions

Science.gov (United States)

Bai, Li; Millwater, Jan; Hudson, Peter

2013-01-01

Workplace influences on Chinese Teaching English as a Foreign Language (TEFL) academics' development as researchers were examined in two Chinese higher education institutions in this qualitative collective case study. Data sources included research documentation and interviews with 12 Chinese TEFL academics. Both institutions were keen on research…

The temperature-dependent microstructure of PEDOT/PSS films: insights from morphological, mechanical and electrical analyses

KAUST Repository

Zhou, Jian

2014-09-24

Poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT/PSS) is a widely used conductive polymer in the field of flexible electronics. The ways its microstructure changes over a broad range of temperatures remain unclear. This paper describes microstructure changes at different temperatures and correlates the microstructure with its physical properties (mechanical and electrical). We used High-Angle Annular Dark-Field Scanning Electron Microscopy (HAADF-STEM) combined with electron energy loss spectroscopy (EELS) to determine the morphology and elemental atomic ratio of the film at different temperatures. These results together with the Atomic Force Microscopy (AFM) analysis provide the foundation for a model of how the temperature affects the microstructure of PEDOT/PSS. Moreover, dynamic mechanical analysis (DMA) and electrical characterization were performed to analyze the microstructure and physical property correlations.

Inverted Planar Perovskite Solar Cells with a High Fill Factor and Negligible Hysteresis by the Dual Effect of NaCl-Doped PEDOT:PSS.

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Hu, Lijun; Sun, Kuan; Wang, Ming; Chen, Wei; Yang, Bo; Fu, Jiehao; Xiong, Zhuang; Li, Xinyi; Tang, Xiaosheng; Zang, Zhigang; Zhang, Shupeng; Sun, Lidong; Li, Meng

2017-12-20

The performance of inverted perovskite solar cells is highly dependent on hole extraction and surface properties of hole transport layers. To highlight the important role of hole transport layers, a facile and simple method is developed by adding sodium chloride (NaCl) into poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). The average power conversion efficiency of the perovskite solar cells prepared on NaCl-doped PEDOT:PSS is 17.1% with negligible hysteresis, compared favorably to the control devices (15.1%). Particularly, they exhibit markedly improved V oc and fill factor (FF), with the best FF as high as 81.9%. The enhancement of photovoltaic performance is ascribed to two effects. Better conductivity and hole extraction of PEDOT:PSS are observed after NaCl doping. More intriguingly, the perovskite polycrystalline film shows a preferred orientation along the (001) direction on NaCl-doped PEDOT:PSS, leading to a more uniform thin film. The comparison of the crystal structure between NaCl and MAPbCl 3 indicates a lattice constant mismatch less than 2% and a matched chlorine atom arrangement on the (001) surface, which implies that the NaCl crystallites on the top surface of PEDOT:PSS might serve as seeds guiding the growth of perovskite crystals. This simple method is fully compatible with printing technologies to mass-produce perovskite solar cells with high efficiency and tunable crystal orientations.

Differences in Learning Characteristics Between Students With High, Average, and Low Levels of Academic Procrastination: Students’ Views on Factors Influencing Their Learning

Directory of Open Access Journals (Sweden)

Lennart Visser

2018-05-01

Full Text Available Within the field of procrastination, much research has been conducted on factors that have an influence on academic procrastination. Less is known about how such factors may differ for various students. In addition, not much is known about differences in the process of how factors influence students’ learning and what creates differences in procrastination behavior between students with different levels of academic procrastination. In this study learning characteristics and the self-regulation behavior of three groups of students with different levels of academic procrastination were compared. The rationale behind this was that certain learning characteristics and self-regulation behaviors may play out differently in students with different levels of academic procrastination. Participants were first-year students (N = 22 with different levels of academic procrastination enrolled in an elementary teacher education program. The selection of the participants into three groups of students (low procrastination, n = 8; average procrastination, n = 8; high procrastination, n = 6 was based on their scores on a questionnaire measuring the students’ levels of academic procrastination. From semi-structured interviews, six themes emerged that describe how students in the three groups deal with factors that influence the students’ learning: degree program choice, getting started with study activities, engagement in study activities, ways of reacting to failure, view of oneself, and study results. This study shows the importance of looking at differences in how students deal with certain factors possibly negatively influencing their learning. Within the group of students with average and high levels of academic procrastination, factors influencing their learning are regularly present. These factors lead to procrastination behavior among students with high levels of academic procrastination, but this seems not the case among students with an average

Differences in Learning Characteristics Between Students With High, Average, and Low Levels of Academic Procrastination: Students' Views on Factors Influencing Their Learning.

Science.gov (United States)

Visser, Lennart; Korthagen, Fred A J; Schoonenboom, Judith

2018-01-01

Within the field of procrastination, much research has been conducted on factors that have an influence on academic procrastination. Less is known about how such factors may differ for various students. In addition, not much is known about differences in the process of how factors influence students' learning and what creates differences in procrastination behavior between students with different levels of academic procrastination. In this study learning characteristics and the self-regulation behavior of three groups of students with different levels of academic procrastination were compared. The rationale behind this was that certain learning characteristics and self-regulation behaviors may play out differently in students with different levels of academic procrastination. Participants were first-year students ( N = 22) with different levels of academic procrastination enrolled in an elementary teacher education program. The selection of the participants into three groups of students (low procrastination, n = 8; average procrastination, n = 8; high procrastination, n = 6) was based on their scores on a questionnaire measuring the students' levels of academic procrastination. From semi-structured interviews, six themes emerged that describe how students in the three groups deal with factors that influence the students' learning: degree program choice, getting started with study activities, engagement in study activities, ways of reacting to failure, view of oneself, and study results. This study shows the importance of looking at differences in how students deal with certain factors possibly negatively influencing their learning. Within the group of students with average and high levels of academic procrastination, factors influencing their learning are regularly present. These factors lead to procrastination behavior among students with high levels of academic procrastination, but this seems not the case among students with an average level of academic

Differences in Learning Characteristics Between Students With High, Average, and Low Levels of Academic Procrastination: Students’ Views on Factors Influencing Their Learning

Science.gov (United States)

Visser, Lennart; Korthagen, Fred A. J.; Schoonenboom, Judith

2018-01-01

Within the field of procrastination, much research has been conducted on factors that have an influence on academic procrastination. Less is known about how such factors may differ for various students. In addition, not much is known about differences in the process of how factors influence students’ learning and what creates differences in procrastination behavior between students with different levels of academic procrastination. In this study learning characteristics and the self-regulation behavior of three groups of students with different levels of academic procrastination were compared. The rationale behind this was that certain learning characteristics and self-regulation behaviors may play out differently in students with different levels of academic procrastination. Participants were first-year students (N = 22) with different levels of academic procrastination enrolled in an elementary teacher education program. The selection of the participants into three groups of students (low procrastination, n = 8; average procrastination, n = 8; high procrastination, n = 6) was based on their scores on a questionnaire measuring the students’ levels of academic procrastination. From semi-structured interviews, six themes emerged that describe how students in the three groups deal with factors that influence the students’ learning: degree program choice, getting started with study activities, engagement in study activities, ways of reacting to failure, view of oneself, and study results. This study shows the importance of looking at differences in how students deal with certain factors possibly negatively influencing their learning. Within the group of students with average and high levels of academic procrastination, factors influencing their learning are regularly present. These factors lead to procrastination behavior among students with high levels of academic procrastination, but this seems not the case among students with an average level of academic

The Effect of Academic Advising on Academic Performance of ...

African Journals Online (AJOL)

Although academic advising in Kenyan universities exists, no research has been done to find out how it impacts on students' educational and career goals. This research aimed at establishing the effect of academic advising on academic performance and the influence of year of study and gender on students' tendency to ...

Reimagining the self at late-career transitions: how identity threat influences academic physicians' retirement considerations.

Science.gov (United States)

Onyura, Betty; Bohnen, John; Wasylenki, Don; Jarvis, Anna; Giblon, Barney; Hyland, Robert; Silver, Ivan; Leslie, Karen

2015-06-01

There is scant empirical work exploring academic physicians' psychosocial adjustment during late-career transitions or on the factors that influence their retirement decisions. The authors examine these issues through the lens of sociopsychological identity theory, specifically examining how identity threat influences academic physicians' decisions about retirement. Participants were academic physicians at a Canadian medical school and were recruited via e-mail requests for clinical faculty interested in discussing late-career and retirement planning issues. Participants included 15 males and 6 females (N = 21; mean age = 63, standard deviation = 7.54), representing eight specialties (clinical and surgical). Data were collected in October and November 2012 via facilitated focus groups, which were digitally recorded, transcribed verbatim, and anonymized, then analyzed using thematic analysis. Four primary themes were identified: centrality of occupational identity, experiences of identity threat, experiences of aging in an indifferent system, and coping with late-career transitions. Identity threats were manifested in apprehensions about self-esteem after retirement, practice continuity, and clinical competence, as well as in a loss of meaning and belonging. These identity challenges influenced decisions on whether to retire. Organizational and system support was perceived as wanting. Coping strategies included reimagining and revaluing various aspects of the self through assimilating new activities and reprioritizing others. Identity-related struggles are a significant feature of academic physicians' considerations about late-career transitions. Understanding these challenges, their antecedents, and their consequences can prepare faculty, and their institutions, to better manage late-career transitions. Individual- and institution-level implications are discussed.

How Is Working Memory Training Likely to Influence Academic Performance? Current Evidence and Methodological Considerations.

Science.gov (United States)

Bergman Nutley, Sissela; Söderqvist, Stina

2017-01-01

Working memory (WM) is one of our core cognitive functions, allowing us to keep information in mind for shorter periods of time and then work with this information. It is the gateway that information has to pass in order to be processed consciously. A well-functioning WM is therefore crucial for a number of everyday activities including learning and academic performance (Gathercole et al., 2003; Bull et al., 2008), which is the focus of this review. Specifically, we will review the research investigating whether improving WM capacity using Cogmed WM training can lead to improvements on academic performance. Emphasis is given to reviewing the theoretical principles upon which such investigations rely, in particular the complex relation between WM and mathematical and reading abilities during development and how these are likely to be influenced by training. We suggest two possible routes in which training can influence academic performance, one through an effect on learning capacity which would thus be evident with time and education, and one through an immediate effect on performance on reading and mathematical tasks. Based on the theoretical complexity described we highlight some methodological issues that are important to take into consideration when designing and interpreting research on WM training and academic performance, but that are nonetheless often overlooked in the current research literature. Finally, we will provide some suggestions for future research for advancing the understanding of WM training and its potential role in supporting academic attainment.

Parental Influence on Academic Achievement among the Primary School Students in Trinidad

Science.gov (United States)

Johnson, Emmanuel Janagan; Descartes, Christine H.

2017-01-01

The present study examined the level of parental influence on academic achievement in primary school students who prepare for the National-level test at standard five (grade 6), Secondary Entrance Examinations in Trinidad. A sample of 128 students studying standard five from primary schools was randomly selected. The data were analysed using SPSS.…

Tailoring the Electrochemical and Mechanical Properties of PEDOT:PSS Films for Bioelectronics

KAUST Repository

Elmahmoudy, Mohammed

2017-02-21

The effect of 3-glycidoxypropyltrimethoxysilane (GOPS) content in poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) dispersions on the properties of films spun cast from these formulations is investigated. It has been found out that the concentration of GOPS has a tremendous, yet gradual impact on the electrical, electrochemical, and mechanical properties of the PEDOT:PSS/GOPS films and that there is an optimum concentration which maximizes a particular feature of the film such as its water uptake or elasticity. The benefits of aqueous stability and mechanical strength with GOPS are to be compensated by an increase in the electrochemical impedance. GOPS aids obtaining excellent mechanical integrity in aqueous media with still highly conducting properties. Moreover, active devices like organic electrochemical transistors that contain 1 wt% GOPS, which is a concentration that leads to film with high electrical conductivity with sufficient mechanical stability and softness, exhibit steady performance over three weeks. These results suggest that variations in the concentration of such an additive like GOPS can enable a facile co-optimization of electrical and mechanical properties of a conducting polymer film for in vivo bioelectronics application.

Flexible and Compressible PEDOT:PSS@Melamine Conductive Sponge Prepared via One-Step Dip Coating as Piezoresistive Pressure Sensor for Human Motion Detection.

Science.gov (United States)

Ding, Yichun; Yang, Jack; Tolle, Charles R; Zhu, Zhengtao

2018-05-09

Flexible and wearable pressure sensor may offer convenient, timely, and portable solutions to human motion detection, yet it is a challenge to develop cost-effective materials for pressure sensor with high compressibility and sensitivity. Herein, a cost-efficient and scalable approach is reported to prepare a highly flexible and compressible conductive sponge for piezoresistive pressure sensor. The conductive sponge, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)@melamine sponge (MS), is prepared by one-step dip coating the commercial melamine sponge (MS) in an aqueous dispersion of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). Due to the interconnected porous structure of MS, the conductive PEDOT:PSS@MS has a high compressibility and a stable piezoresistive response at the compressive strain up to 80%, as well as good reproducibility over 1000 cycles. Thereafter, versatile pressure sensors fabricated using the conductive PEDOT:PSS@MS sponges are attached to the different parts of human body; the capabilities of these devices to detect a variety of human motions including speaking, finger bending, elbow bending, and walking are evaluated. Furthermore, prototype tactile sensory array based on these pressure sensors is demonstrated.

The influence of gender on personality variables conditioning learning: Emotional intelligence and academic procrastination

Directory of Open Access Journals (Sweden)

Mercè Clariana,

2011-10-01

Full Text Available This research analyses the relationship between academic procrastination and emotional intelligence taking also into account the gender and age influence. Psychology undergraduates from the UAB (Universitat Autónoma de Barcelona, Spain and the UIB (Universitat de les Illes Balears, Spain, 45 males and 147 females constituted the sample of the study. Academic procrastination was assessed by means of the D scale (CLARIANA & MARTÍN, 2008 and emotional intelligence by means of the EQ–i (BAR–ON, 1997. The results show that academic procrastination has a significant negative relationship with intrapersonal intelligence, emotional quotient and mood. Moreover, female students scored significantly higher than males both in intrapersonal and interpersonal Intelligence while males obtained higher scores in both stress management and adaptability.

Influence of study satisfaction on academic procrastination in psychology students: a preliminary study

Directory of Open Access Journals (Sweden)

Sergio Alexis Dominguez-Lara

2017-06-01

Full Text Available The aim of this predictive study was to analyze the degree of influence of study satisfaction (SS on academic procrastination (AP. One hundred forty- eight (148 psychology students (111 women between 18 and 32 years old (M = 22.41 were evaluated using the Brief Scale of Study Satisfaction and the Academic Procrastination Scale. After preliminary analyses focused on the scores reliability (α > 0.70 and correlations between dimensions, a regression analysis was performed to determine how much of the variability in the AP dimensions’ scores is explained by the variations in the SS. For that purpose, a method that uses bivariate correlations corrected for attenuation and provides confidence intervals under a bootstrap approach of the associated statistics was applied. All analyses were assessed from an effect size approach. The results indicate that the influence of SS on AP was not significant. These findings provide new ways to implement studies in order to understand the procrastinating behavior in the university setting.

Hybrid device based on GaN nanoneedles and MEH-PPV/PEDOT:PSS polymer

International Nuclear Information System (INIS)

Shin, Min Jeong; Gwon, Dong-Oh; Lee, Chan-Mi; Lee, Gang Seok; Jeon, In-Jun; Ahn, Hyung Soo; Yi, Sam Nyung; Ha, Dong Han

2015-01-01

Highlights: • A hybrid device was demonstrated by using MEH-PPV, PEDOT:PSS, and GaN nanoneedles. • I–V curve of the hybrid device showed its rectification behaviour, similar to a diode. • EL peak originated by the different potential barriers at MEH-PPV and GaN interface. - Abstract: A hybrid device that combines the properties of organic and inorganic semiconductors was fabricated and studied. It incorporated poly[2-methoxy-5-(2-ethylhexyloxy)- 1,4-phenylenevinylene] (MEH-PPV) and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as organic polymers and GaN nanoneedles as an inorganic semiconductor. Layers of the two polymers were spin coated on to the GaN nanoneedles. The one peak in the electroluminescence spectrum originated from the MEH-PPV layer owing to the different potential barriers of electrons and holes at its interface with the GaN nanoneedles. However, the photoluminescence spectrum showed peaks due to both GaN nanoneedles and MEH-PPV. Such hybrid structures, suitably developed, might be able to improve the efficiency of optoelectronic devices

Hybrid device based on GaN nanoneedles and MEH-PPV/PEDOT:PSS polymer

Energy Technology Data Exchange (ETDEWEB)

Shin, Min Jeong; Gwon, Dong-Oh; Lee, Chan-Mi; Lee, Gang Seok [Department of Applied Science, Korea Maritime and Ocean University, Busan 606-791 (Korea, Republic of); Jeon, In-Jun [Department of Nano-semiconductor Engineering, Korea Maritime and Ocean University, Busan 606-791 (Korea, Republic of); Ahn, Hyung Soo [Department of Applied Science, Korea Maritime and Ocean University, Busan 606-791 (Korea, Republic of); Department of Nano-semiconductor Engineering, Korea Maritime and Ocean University, Busan 606-791 (Korea, Republic of); Yi, Sam Nyung, E-mail: snyi@kmou.ac.kr [Department of Applied Science, Korea Maritime and Ocean University, Busan 606-791 (Korea, Republic of); Department of Nano-semiconductor Engineering, Korea Maritime and Ocean University, Busan 606-791 (Korea, Republic of); Ha, Dong Han [Division of Convergence Technology, Korea Research Institute of Standards and Science, Daejeon 305-340 (Korea, Republic of)

2015-08-15

Highlights: • A hybrid device was demonstrated by using MEH-PPV, PEDOT:PSS, and GaN nanoneedles. • I–V curve of the hybrid device showed its rectification behaviour, similar to a diode. • EL peak originated by the different potential barriers at MEH-PPV and GaN interface. - Abstract: A hybrid device that combines the properties of organic and inorganic semiconductors was fabricated and studied. It incorporated poly[2-methoxy-5-(2-ethylhexyloxy)- 1,4-phenylenevinylene] (MEH-PPV) and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as organic polymers and GaN nanoneedles as an inorganic semiconductor. Layers of the two polymers were spin coated on to the GaN nanoneedles. The one peak in the electroluminescence spectrum originated from the MEH-PPV layer owing to the different potential barriers of electrons and holes at its interface with the GaN nanoneedles. However, the photoluminescence spectrum showed peaks due to both GaN nanoneedles and MEH-PPV. Such hybrid structures, suitably developed, might be able to improve the efficiency of optoelectronic devices.

Reversible structural transformation and enhanced performance of PEDOT:PSS-based hybrid solar cells driven by light intensity.

Science.gov (United States)

Thomas, Joseph Palathinkal; Srivastava, Saurabh; Zhao, Liyan; Abd-Ellah, Marwa; McGillivray, Donald; Kang, Jung Soo; Rahman, Md Anisur; Moghimi, Nafiseh; Heinig, Nina F; Leung, Kam Tong

2015-04-15

Hybrid solar cells made of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) ( PSS) and appropriate amounts of a cosolvent and a fluorosurfactant on planar n-type silicon substrates showed a photoconversion efficiency (PCE) of above 13%. These cells also exhibited stable, reproducible, and high external quantum efficiency (EQE) that was not sensitive to light-bias intensity (LBI). In contrast, solar cells made of pristine PSS showed low PCE and high EQE only under certain measurement conditions. The EQE was found to degrade with increasing LBI. Here we report that the LBI-sensitive variation of EQE of the low-PCE cells is related to a reversible structural transformation from a quinoid to a benzoid structure of PEDOT.

A paper-based electrode using a graphene dot/PEDOT:PSS composite for flexible solar cells

KAUST Repository

Lee, Chuan-Pei; Lai, Kun-Yu; Lin, Chin-An; Li, Chun-Ting; Ho, Kuo-Chuan; Wu, Chih-I; Lau, Shu-Ping; He, Jr-Hau

2017-01-01

We have synthesized a metal-free composite ink that contains graphene dots (GDs) and poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) that can be used on paper to serve as the counter electrode in a flexible dye-sensitized solar

Reliability prediction for the vehicles equipped with advanced driver assistance systems (ADAS and passive safety systems (PSS

Directory of Open Access Journals (Sweden)

Balbir S. Dhillon

2012-10-01

Full Text Available The human error has been reported as a major root cause in road accidents in today’s world. The human as a driver in road vehicles composed of human, mechanical and electrical components is constantly exposed to changing surroundings (e.g., road conditions, environmentwhich deteriorate the driver’s capacities leading to a potential accident. The auto industries and transportation authorities have realized that similar to other complex and safety sensitive transportation systems, the road vehicles need to rely on both advanced technologies (i.e., Advanced Driver Assistance Systems (ADAS and Passive Safety Systems (PSS (e.g.,, seatbelts, airbags in order to mitigate the risk of accidents and casualties. In this study, the advantages and disadvantages of ADAS as active safety systems as well as passive safety systems in road vehicles have been discussed. Also, this study proposes models that analyze the interactions between human as a driver and ADAS Warning and Crash Avoidance Systems and PSS in the design of vehicles. Thereafter, the mathematical models have been developed to make reliability prediction at any given time on the road transportation for vehicles equipped with ADAS and PSS. Finally, the implications of this study in the improvement of vehicle designs and prevention of casualties are discussed.

Solution-processed highly conductive PEDOT:PSS/AgNW/GO transparent film for efficient organic-Si hybrid solar cells.

Science.gov (United States)

Xu, Qiaojing; Song, Tao; Cui, Wei; Liu, Yuqiang; Xu, Weidong; Lee, Shuit-Tong; Sun, Baoquan

2015-02-11

Hybrid solar cells based on n-Si/poly(3,4-ethylenedioxythiophene):poly(styrene- sulfonate) (PEDOT:PSS) heterojunction promise to be a low cost photovoltaic technology by using simple device structure and easy fabrication process. However, due to the low conductivity of PEDOT:PSS, a metal grid deposited by vacuum evaporation method is still required to enhance the charge collection efficiency, which complicates the device fabrication process. Here, a solution-processed graphene oxide (GO)-welded silver nanowires (AgNWs) transparent conductive electrode (TCE) was employed to replace the vacuum deposited metal grid. A unique "sandwich" structure was developed by embedding an AgNW network between PEDOT:PSS and GO with a figure-of-merit of 8.6×10(-3) Ω(-1), which was even higher than that of sputtered indium tin oxide electrode (6.6×10(-3) Ω(-1)). A champion power conversion efficiency of 13.3% was achieved, because of the decreased series resistance of the TCEs as well as the enhanced built-in potential (Vbi) in the hybrid solar cells. The TCEs were obtained by facile low-temperature solution process method, which was compatible with cost-effective mass production technology.

Planning Support Systems (PSS-Based Spatial Plan Alternatives and Environmental Assessment

Directory of Open Access Journals (Sweden)

Hee-Sun Choi

2016-03-01

Full Text Available Spatial planning is at the core of national land and urban development. Many countries and cities seek sustainable development through various means such as coordinated environmental planning, environmental assessment, and internalization of environmental analysis and planning. A Planning Support System (PSS is a GIS (Geographic Information System-based, spatial decision-making support system that incorporates a variety of theories and pertinent models. This study adopted the “What if?” model to design an alternative spatial plan that includes generation of predictive scenarios and is relatively easy to use. In the cities studied, we identified a total of six scenarios based on the main drivers of development—namely, population and spatial policies. Subsequently, we assessed the alternatives for their environmental impact, preparing sensitivity maps for each major environmental issue in the target area (natural ecosystem, air and microclimate, natural disasters. One projected advantage of the “What if?” model is that its digital visualization of proposed plans may improve public awareness and involvement. Furthermore, the tool is expected to be highly useful in ensuring the objectivity of quantitative analyses. However, it is necessary to develop a PSS that is both standardized and tailored to the particular needs of each area. Finally, the development of an e-governance system will be beneficial in ensuring public access to the decision making process.

Costs on the Mind: the Influence of the Financial Burden of College on Academic Performance and Cognitive Functioning

Science.gov (United States)

Destin, Mesmin; Svoboda, Ryan C.

2018-01-01

The current studies test the hypothesis that the financial burden of college can initiate a psychological process that has a negative influence on academic performance for students at selective colleges and universities. Prior studies linking high college costs and student loans to academic outcomes have not been grounded within relevant social…

Social Consequences of Academic Teaming in Middle School: The Influence of Shared Course-Taking on Peer Victimization

Science.gov (United States)

Echols, Leslie

2014-01-01

This study examined the influence of academic teaming (i.e., sharing academic classes with the same classmates) on the relationship between social preference and peer victimization among 6th grade students in middle school. Approximately 1,000 participants were drawn from 5 middle schools that varied in their practice of academic teaming. A novel methodology for measuring academic teaming at the individual level was employed, in which students received their own teaming score based on the unique set of classmates with whom they shared academic courses in their class schedule. Using both peer- and self-reports of victimization, the results of two path models indicated that students with low social preference in highly teamed classroom environments were more victimized than low preference students who experienced less teaming throughout the school day. This effect was exaggerated in higher performing classrooms. Implications for the practice of academic teaming were discussed. PMID:25937668

An investigation of the structure–property relationships in ionic polymer polymer composites (IP2Cs) manufactured by polymerization in situ of PEDOT/PSS on Nafion®117

International Nuclear Information System (INIS)

Di Pasquale, G; Messina, F G; Pollicino, A; Puglisi, R; Graziani, S; Umana, E

2014-01-01

Ionic polymer polymer composites (IP 2 Cs) are all-organic electroactive polymers (EAPs) that show sensing and actuation capabilities when a deformation or a voltage is applied, respectively. They are fabricated starting from an ionic polymer coated on both sides with a conducting polymer as electrode element. In this work, poly(3,4-ethylendioxytiophene)–poly-(styrenesulfonate) (PEDOT/PSS) has been polymerized directly on Nafion ® 117 membrane and devices have been manufactured varying the polymerization time. Water and ethylene glycol (EG) have been used as solvents. The obtained IP 2 Cs have been characterized using thermal and mechanical analyses and electromechanically tested. The results have shown that in IP 2 Cs manufactured by polymerization in situ the PEDOT/PSS layer adheres very strongly on the Nafion ® 117 film, improving the possibility of rehydrating the devices after use. Moreover, taking into account that the different polymerization times influence the uniformity of the surface of the organic electrode and, consequently, both device stiffness and electrode conductivity, the structure–property relationships of the obtained devices have been investigated. The influence of the different solvents inside the devices has also been studied when IP 2 Cs have been used as actuators or sensors. Reported results show that it is possible to modulate the performances of IP 2 Cs by varying some manufacture parameters and the solvent. (paper)

Electrical characterization of the ITO/NiPc/PEDOT : PSS junction diode

Energy Technology Data Exchange (ETDEWEB)

Shah, Mutabar; Sayyad, M H; Karimov, Kh S; Wahab, Fazal, E-mail: mutabar_shah@hotmail.co, E-mail: mutabarshah@gmail.co [Ghulam Ishaq Khan Institute of Engineering Sciences and Technology, Topi, District Swabi, Khyber Pakhtunkhwa 23640 (Pakistan)

2010-10-13

This paper reports on the fabrication and characterization of an ITO/NiPc/PEDOT : PSS junction diode. A thin film of nickel phthalocyanine (NiPc) was deposited by the thermal vacuum deposition method on indium tin oxide (ITO) used as a substrate. The current-voltage characteristics of the diode were measured at room temperature under dark condition and showed rectifying behaviour. The values of several electrical parameters such as ideality factor, barrier height, conductivity, and series and shunt resistances were calculated.

The electronic properties of the interface between nickel phthalocyanine and a PEDOT:PSS film

Czech Academy of Sciences Publication Activity Database

Petraki, F.; Kennou, S.; Nešpůrek, Stanislav

2008-01-01

Roč. 103, č. 3 (2008), 033710/1-033710/6 ISSN 0021-8979 R&D Projects: GA AV ČR KAN401770651; GA MŠk OC 138 Institutional research plan: CEZ:AV0Z40500505 Keywords : NiPC * PEDOT:PSS * XPS Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.201, year: 2008

Microtexturing of the conductive PEDOT:PSS Polymer for superhydrophobic organic electrochemical transistors

KAUST Repository

Gentile, Francesco

2014-01-22

Superhydrophobic surfaces are bioinspired, nanotechnology artifacts, which feature a reduced friction coefficient, whereby they can be used for a number of very practical applications including, on the medical side, the manipulation of biological solutions. In this work, we integrated superhydrophobic patterns with the conducting polymer PEDOT:PSS, one of the most used polymers in organic electronics because highly sensitive to ionized species in solution. In doing so, we combined geometry and materials science to obtain an advanced device where, on account of the superhydrophobicity of the system, the solutions of interest can be manipulated and, on account of the conductive PEDOT:PSS polymer, the charged molecules dispersed inside can be quantitatively measured. This original substrate preparation allowed to perform electrochemical measurements on ionized species in solution with decreasing concentration down to 10 -7 molar. Moreover, it was demonstrated the ability of the device of realizing specific, combined time and space resolved analysis of the sample. Collectively, these results demonstrate how a tight, interweaving integration of different disciplines can provide realistic tools for the detection of pathologies. The scheme here introduced offers breakthrough capabilities that are expected to radically improve both the pace and the productivity of biomedical research, creating an access revolution. 2014 Francesco Gentile et al.

THE INFLUENCE OF PARENTS’ EDUCATIONAL BACKGROUND AND STUDY FACILITIES ON ACADEMIC PERFORMANCE AMONG SECONDARY SCHOOL STUDENTS

OpenAIRE

ALOKAN, FUNMILOLA BOSEDE; OSAKINLE, EUNICE OLUFUNMILAYO; ONIJINGIN, EMMANUEL OLUBU

2013-01-01

There has been an outcry against the poor performance of students in the Senior Secondary Certificate Examination in Nigeria. This study investigated the difference between the academic performance of students from parents with high educational background and students from parents with low educational background. It also investigated the influence of having study facilities at home on academic performance. The population for this study comprised all public secondary school students in Ondo St...

Culture and Climate: Factors That Influence the Academic Success of African American Students in Prelicensure Nursing Education.

Science.gov (United States)

Murray, Teri A

2015-12-01

Despite numerous calls to diversify the nursing workforce, little progress has been made in increasing the numbers of African American graduates from prelicensure nursing programs, thus widening the diversity gap in the number of African Americans who enter the RN workforce. An integrative literature review was conducted to determine whether, from the students' perspective, the institutional climate and culture influenced their academic success. Themes of Alienation and Isolation, Persistent Determination, and Difficulty Seeking Help emerged as having an influence on students' academic success. On the basis of this review, professional development programs on topics such as implicit bias, microaggressions, and other unintentional and unconscious behaviors are recommended. Copyright 2015, SLACK Incorporated.

Script Towards Research 2.0: The Influence of Digital and Online Tools in Academic Research

Directory of Open Access Journals (Sweden)

Gabriela Grosseck

2016-07-01

Full Text Available The new Internet technologies have infiltrated in a stunning way the academic environment, both at individual and at institutional level. Therefore, more and more teachers have started educational blogs, librarians are active on Twitter, other educational actors curate web content, students post on Instagram or Flickr, and university departments have Facebook pages and/or YouTube accounts etc. Today, the use of web technology has become “a legitimate activity in many areas of higher education” (Waycott, 2010 and a considerable shift to digital academic research has gradually occurred. Teachers are encouraging students to take up digital tools for research and writing, thus revealing new ways of using information and communication technologies for academic purposes and not just for socializing. The main objective of this paper is to investigate the effects of integrating diverse digital, Web 2.0 tools and resources and OERs/MOOCs in research and in the construction of students’ academic texts. We aim to stress the increasing influence of digital and online tools in academic research and writing. Teachers, specialists, and students alike are affected by this process. In order to show how, we explore the following issues: What is Research 2.0? Which digital/online tools have we used to assist our students? What are the challenges for academic research using digital / web 2.0 tools? And how do digital tools shape academic research?

Optoelectronic Evaluation and Loss Analysis of PEDOT:PSS/Si Hybrid Heterojunction Solar Cells.

Science.gov (United States)

Yang, Zhenhai; Fang, Zebo; Sheng, Jiang; Ling, Zhaoheng; Liu, Zhaolang; Zhu, Juye; Gao, Pingqi; Ye, Jichun

2017-12-01

The organic/silicon (Si) hybrid heterojunction solar cells (HHSCs) have attracted considerable attention due to their potential advantages in high efficiency and low cost. However, as a newly arisen photovoltaic device, its current efficiency is still much worse than commercially available Si solar cells. Therefore, a comprehensive and systematical optoelectronic evaluation and loss analysis on this HHSC is therefore highly necessary to fully explore its efficiency potential. Here, a thoroughly optoelectronic simulation is provided on a typical planar polymer poly (3,4-ethylenedioxy thiophene):polystyrenesulfonate (PEDOT:PSS)/Si HHSC. The calculated spectra of reflection and external quantum efficiency (EQE) match well with the experimental results in a full-wavelength range. The losses in current density, which are contributed by both optical losses (i.e., reflection, electrode shield, and parasitic absorption) and electrical recombination (i.e., the bulk and surface recombination), are predicted via carefully addressing the electromagnetic and carrier-transport processes. In addition, the effects of Si doping concentrations and rear surface recombination velocities on the device performance are fully investigated. The results drawn in this study are beneficial to the guidance of designing high-performance PEDOT:PSS/Si HHSCs.

Connections, Productivity and Funding: An Examination of Factors Influencing Scientists' Perspectives on the Market Orientation of Academic Research

Science.gov (United States)

Ronning, Emily Anne

2012-01-01

This study examines scientists' perceptions of the environment in which they do their work. Specifically, this study examines how academic and professional factors such as research productivity, funding levels for science, connections to industry, type of academic appointment, and funding sources influence scientists' perceptions of the…

Damping Improvement of Multiple Damping Controllers by Using Optimal Coordinated Design Based on PSS and FACTS-POD in a Multi-Machine Power System

Directory of Open Access Journals (Sweden)

Ali Nasser Hussain

2016-09-01

Full Text Available The aim of this study is to present a comprehensive comparison and assessment of the damping function improvement of power system oscillation for the multiple damping controllers using the simultaneously coordinated design based on Power System Stabilizer (PSS and Flexible AC Transmission System (FACTS devices. FACTS devices can help in the enhancing the stability of the power system by adding supplementary damping controller to the control channel of the FACTS input to implement the task of Power Oscillation Damping (FACT POD controller. Simultaneous coordination can be performed in different ways. First, the dual coordinated designs between PSS and FACTS POD controller or between different FACTS POD controllers are arranged in a multiple FACTS devices without PSS. Second, the simultaneous coordination has been extended to triple coordinated design among PSS and different FACTS POD controllers. The parameters of the damping controllers have been tuned in the individual controllers and coordinated designs by using a Chaotic Particle Swarm Optimization (CPSO algorithm that optimized the given eigenvalue-based objective function. The simulation results for a multi-machine power system show that the dual coordinated design provide satisfactory damping performance over the individual control responses. Furthermore, the triple coordinated design has been shown to be more effective in damping oscillations than the dual damping controllers.

Academic Entrepreneurship and Traditional Academic Duties: Synergy or Rivalry?

Science.gov (United States)

De Silva, Muthu

2016-01-01

This study investigates the influence of academic entrepreneurship on traditional academic duties carried out in a resource-constrained environment, particularly focusing on whether there is synergy or rivalry between these two activities. Using qualitative evidence, we discover that there are funding, resource, knowledge and skill and networking…

PEDOT: PSS: rGO nanocomposite as a hole transport layer (HTLs) for P3HT:PCBM based organic solar cells

Science.gov (United States)

Tiwari, D. C.; Dwivedi, Shailendra Kumar; Dipak, Pukhrambam; Chandel, Tarun

2018-05-01

This paper reports the fabrication process of organic solar cell (OSCs) having structure ITO/PEDOT:PSS:rGO/P3HT:PCBM/Al. In this cell, poly (3, 4-ethylenedioxythiophene): poly (styrenesulfonate) (PEDOT: PSS) is ultrasonically mixed with thermally reduced graphene oxide (rGO), which was used as a hole transport layer (HTLs). In order to investigate structural, morphological and optical properties of nanocomposite, XRD, FE-SEM and UV-vis spectroscopy were carried out. We have observed, Jsc = 6.5mA/cm2, Voc = 212 mV, FF=0.31 and PCE of 0.43% from fabricated organic solar cell.

Stretchable and Hydrophobic Electrochromic Devices Using Wrinkled Graphene and PEDOT:PSS

Directory of Open Access Journals (Sweden)

Srinivasa Kartik Nemani

2018-01-01

Full Text Available We present an electrochromic device (ECD fabricated using PEDOT:PSS and graphene as active conductive electrode films and a flexible compliant polyurethane substrate with 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonylimide (EMI-TSFI additive, as ionic medium. This device with a docile, elastic intermediate substrate along with a transparency controlled PEDOT:PSS film provides a wide color contrast and fast switching rate. We harness wrinkling instability of graphene to achieve a hydrophobic nature without compromising transparency of the ECD. This mechanical self-assembly approach helps in controlling the wavelength of wrinkles generated by inducing measured prestrain conditions and regulating the modulus contrast by selection of underlying materials used, hereby controlling the extent of transparency. The reduction and oxidation switching times for the device were analyzed to be 5.76 s and 5.34 s for a 90% transmittance change at an operating DC voltage of 15 ± 0.1 V. Strain dependent studies show that the performance was robust with the device retaining switching contrasts even at 15% uniaxial strain conditions. Our device also exhibits superior antiwetting properties with an average water contact angle of 110°  ± 2° at an induced radial prestrain of 30% in the graphene film. A wide range color contrast, flexibility, and antiwetting nature of the device envision its uses in smart windows, visors, and other wearable equipment where these functionalities are of outmost importance for developing new generation of smart interactive devices.

Teachers' Perceptions of How They Influence Student Academic Performance in VCE Physical Education

Science.gov (United States)

Whittle, Rachael J.; Telford, Amanda; Benson, Amanda C.

2018-01-01

This research explored teacher perceptions of how they influence academic performance of Victorian Certificate of Education (VCE) Physical Education students. VCE Physical Education teachers (n = 37) from 31 secondary schools in Victoria, Australia participated in a qualitative study using focus groups with a semi-structured interview schedule.…

The influence of learning styles, enrollment status and gender on academic performance of optometry undergraduates.

Science.gov (United States)

Prajapati, Bhavna; Dunne, Mark; Bartlett, Hannah; Cubbidge, Robert

2011-01-01

This cross-sectional study was designed to determine whether the academic performance of optometry undergraduates is influenced by enrollment status, learning style or gender. Three hundred and sixty undergraduates in all 3 years of the optometry degree course at Aston University during 2008-2009 were asked for their informed consent to participate in this study. Enrollment status was known from admissions records. An Index of Learning Styles (http://www4.nscu.edu/unity/lockers/users/f/felder/public/Learning-Styles.html) determined learning style preference with respect to four different learning style axes; active-reflective, sensing-intuitive, visual-verbal and sequential-global. The influence of these factors on academic performance was investigated. Two hundred and seventy students agreed to take part (75% of the cohort). 63% of the sample was female. There were 213 home non-graduates (entrants from the UK or European Union without a bachelor's degree or higher), 14 home graduates (entrants from the UK or European Union with a bachelor's degree or higher), 28 international non-graduates (entrants from outside the UK or European Union without a bachelor's degree or higher) and 15 international graduates (entrants from outside the UK or European Union with a bachelor's degree or higher). The majority of students were balanced learners (between 48% and 64% across four learning style axes). Any preferences were towards active, sensing, visual and sequential learning styles. Of the factors investigated in this study, learning styles were influenced by gender; females expressed a disproportionate preference for the reflective and visual learning styles. Academic performance was influenced by enrollment status; international graduates (95% confidence limits: 64-72%) outperformed all other student groups (home non graduates, 60-62%; international non graduates, 55-63%) apart from home graduates (57-69%). Our research has shown that the majority of optometry students

How Students' Beliefs about Their Intelligence Influence Their Academic Performance. Information Capsule. Volume 1012

Science.gov (United States)

Blazer, Christie

2011-01-01

Students' academic success may be influenced not only by their actual ability, but also by their beliefs about their intelligence. Studies have found that students enter a classroom with one of two distinct conceptions of their intellectual ability: some students believe their intelligence is expandable (growth mindset), while others believe their…

Risk Management Challenges in Large-scale Energy PSS

DEFF Research Database (Denmark)

Tegeltija, Miroslava; Oehmen, Josef; Kozin, Igor

2017-01-01

Probabilistic risk management approaches have a long tradition in engineering. A large variety of tools and techniques based on the probabilistic view of risk is available and applied in PSS practice. However, uncertainties that arise due to lack of knowledge and information are still missing...... adequate representations. We focus on a large-scale energy company in Denmark as one case of current product/servicesystems risk management best practices. We analyze their risk management process and investigate the tools they use in order to support decision making processes within the company. First, we...... identify the following challenges in the current risk management practices that are in line with literature: (1) current methods are not appropriate for the situations dominated by weak knowledge and information; (2) quality of traditional models in such situations is open to debate; (3) quality of input...

Electrochemical Impedance Analysis of a PEDOT:PSS-Based Textile Energy Storage Device

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Ida Nuramdhani

2017-12-01

Full Text Available A textile-based energy storage device with electroactive PEDOT:PSS (poly(3,4-ethylenedioxythiophene/poly(4-styrenesulfonate polymer functioning as a solid-state polyelectrolyte has been developed. The device was fabricated on textile fabric with two plies of stainless-steel electroconductive yarn as the electrodes. In this study, cyclic voltammetry and electrochemical impedance analysis were used to investigate ionic and electronic activities in the bulk of PEDOT:PSS and at its interfaces with stainless steel yarn electrodes. The complex behavior of ionic and electronic origins was observed in the interfacial region between the conductive polymer and the electrodes. The migration and diffusion of the ions involved were confirmed by the presence of the Warburg element with a phase shift of 45° (n = 0.5. Two different equivalent circuit models were found by simulating the model with the experimental results: (QR(QR(QR for uncharged and (QR(QR(Q(RW for charged samples. The analyses also showed that the further the distance between electrodes, the lower the capacitance of the cell. The distribution of polymer on the cell surface also played important role to change the capacitance of the device. The results of this work may lead to a better understanding of the mechanism and how to improve the performance of the device.

Covalently Bonded Polyaniline and para-phenylenediamine Functionalized Graphene Oxide: How the Conductive Two-dimensional Nanostructure Influences the Electrochromic Behaviors of Polyaniline

International Nuclear Information System (INIS)

Xiong, Shanxin; Li, Zhufeng; Gong, Ming; Wang, Xiaoqin; Fu, Jialun; Shi, Yujing; Wu, Bohua; Chu, Jia

2014-01-01

Graphical abstract: - Abstract: Polyaniline (PANI) was attached onto the reduced graphene oxide (rGO) sheets through copolymerization of aniline with a para-phenylenediamine (PPD) functionalized graphene oxide (GO-PPD) using the poly(styrene sulfonate) (PSS) as the macromolecular dopant agent to produce a water-dispersible electrochromic material. The structures and the morphologies analysis confirm that the final electrochromic materials (rGO-PANI) are the mixture of PANI/PSS and the covalently bonded rGO-PANI (rGO-PANI hybrid). The rGO-PANI hybrid can be found to form a parallel arrangement to the substrate in the spin-coated film. This parallel arrangement of the layered two-dimensional nanostructure of rGO-PANI hybrid may narrow the ion transportation pathways of the exchanged ions, which will result in a high charge transfer resistance and slow switching speed. Meanwhile, with the conductive rGO added, the electrical conductivity of the electrochromic layer will be increased, which will benefit to low charge transfer resistance and high optical contrast. So the conductive two-dimensional nanostructure has a double-face influence on the electrochromic performances of PANI, which include a positive influence on the electrical conductivity and a negative influence on the ion diffusion. The overall influences depend on the loading amount of GO-PPD. With 4 wt.% GO-PPD feeding, the optical contrast was enhanced by 36% from 0.38 for PANI/PSS to 0.52 for rGO-PANI-3, while the coloration time was almost same as that of PANI/PSS and the bleaching time was decreased by ∼20% from 9.1s for PANI/PSS to 7.4s for rGO-PANI-3. The electrochemical tests showed that with the increasing of GO-PPD loading, the peak currents of cyclic voltammetry (CV) curves were increased, and the peak locations shifted to the positive potential for oxidation peak and the negative potential for reduction peak, respectively, which confirmed that the double-face influences of rGO-PANI on the

Influence of admission marks on the academic performance of technical architecture students

OpenAIRE

Gaspar Fàbregas, Kàtia; Núñez Andrés, María Amparo; Rodríguez Jordana, Juan; Jordana Riba, Francisco de Paula

2016-01-01

Traditionally, students from higher training cycle and upper secondary school education access higher technical education with a wide range of access marks in each group. The purpose of this article is to analyse how students’ backgrounds and access marks really influence their success in the first academic year and further evolution to obtain the degree of Technical Architecture. To achieve this aim, the progress of students from different backgrounds was analysed for three acade...

Direct laser interference patterning of poly(3,4-ethylene dioxythiophene)-poly(styrene sulfonate) (PEDOT-PSS) thin films

International Nuclear Information System (INIS)

Lasagni, Andres F.; Hendricks, Jeffrey L.; Shaw, Charles M.; Yuan, Dajun; Martin, David C.; Das, Suman

2009-01-01

We have developed a patterning procedure based on selective ablation using interference patterns with ns-laser pulses to fabricate periodic arrays on large areas of poly(3,4-ethylene dioxythiophene)-poly(4-styrene sulfonic acid) (PEDOT-PSS) thin films over a metallic gold-palladium layer. Single pulse laser-ablation experiments were performed to study the ablation characteristics of the thin films as a function of the film thickness. The ablation threshold fluence of the PEDOT-PSS films was found to be dependent on thickness with values ranging from 43 mJ/cm 2 to 252 mJ/cm 2 . Additionally, fluences at which the PEDOT-PSS films could be ablated without inducing damage in the underlying metallic films were observed (128 mJ/cm 2 and 402 mJ/cm 2 for film thicknesses of 70 nm and 825 nm, respectively). Linear periodic arrays with line spacings of 7.82 μm and 13.50 μm were also fabricated. The surface topography of these arrays was analyzed using scanning electron and atomic force microscopy. For thicker polymeric layers, several peeled sub-layers of the conjugated polymer with average thicknesses of about 165-185 nm were observed in the ablation experiments. The size and scale of structures produced by this technique could be suitable for several biomedical applications and devices in which controlling cell adhesion, promoting cell alignment, or improving biocompatibility are important.

Human estrogen receptor (ESR) gene locus: PssI dimorphism

Energy Technology Data Exchange (ETDEWEB)

Coleman, R T; Taylor, J E; Frossard, P M [California Biotechnology Inc., Mountain View, CA (USA); Shine, J J [Garvan Institute, Darlinghurst (Australia)

1988-07-25

pESR-2, a 2.1 kb partial cDNA containing the entire translated sequence of the human estrogen receptor mRNA isolated from MCF-7 human breast cancer cells, was subcloned in the Eco RI site of pBR322. PssI (PuGGNCCPy) identifies a single two-allele polymorphism with bands at either 1.7 or 1.4 kb, as well as invariant bands at 12.6, 9.3, 4.1, 3.7, 2.4, 2.2, and 1.2 kb. Its frequency was studied in 77 unrelated North American Caucasians. The human estrogen receptor gene has been localized to 6q24 -- q27 by in situ hybridization. Co-dominant segregation is demonstrated in one family (8 individuals).

Análise fatorial confirmatória das três versões da Perceived Stress Scale (PSS: um estudo populacional

Directory of Open Access Journals (Sweden)

André Faro

2015-03-01

Full Text Available Este estudo teve como objetivos realizar a análise fatorial confirmatória da Escala de Estresse Percebido (Perceived Stress Scale- PSS, nas versões traduzidas de 14, 10 e 4 itens; analisar sua validade concorrente com o Questionário de Saúde Geral (QSG-12; mapear o perfil do estresse em uma amostra representativa da população; e estabelecer parâmetros de avaliação do estresse por meio da normatização dos escores da população total. A amostragem foi de base populacional, em formato de conglomerado por setores censitários. Participaram 1.154 habitantes de uma capital do Nordeste brasileiro, sendo a maioria do sexo feminino (55,6%, com nível de escolaridade em ensino médio (51,7%, empregados (72,7% e não tabagistas (90,6%. As medianas de renda e idade ficaram em R$ 1.200,00 e 29 anos. Ao final, constatou-se que houve ajustes satisfatórios para as três versões da PSS apenas em seu modelo bifatorial e a escala com 10 itens se mostrou uma solução harmônica entre as versões completa e mais reduzida, considerando-se a relação entre a parcimônia na quantidade de itens e a robustez estatística deste instrumento. Ademais, a PSS ratificou sua validade concorrente com o QSG-12 e foi feita a normatização dos escores da PSS, estabelecendo-se parâmetros para comparação em futuros estudos.

High Mobility, Hole Transport Materials for Highly Efficient PEDOT:PSS Replacement in Inverted Perovskite Solar Cells

KAUST Repository

Neophytou, Marios

2017-04-24

Perovskite solar cells are one of the most promising photovoltaic technologies, due to their rapid increase in power conversion efficiency (3.8% to 21.1%) in a very short period of time and the relative ease of their fabrication compared to traditional inorganic solar cells. One of the drawbacks of perovskite solar cells is their limited stability in non-inert atmospheres. In the inverted device configuration this lack of stability can be attributed to the inclusion of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate(PEDOT:PSS) as the hole transporting layer. Herein we report the synthesis of two new triarylamine based hole transporting materials, synthesised from readily available starting materials. These new materials show increased power conversion efficiencies, of 13.0% and 12.1%, compared to PEDOT:PSS (10.9%) and exhibit increased stability achieving lifetimes in excess of 500 hours. Both molecules are solution processible at low temperatures and offer potential for low cost, scalable production on flexible substrates for large scale perovskite solar cells.

High Mobility, Hole Transport Materials for Highly Efficient PEDOT:PSS Replacement in Inverted Perovskite Solar Cells

KAUST Repository

Neophytou, Marios; Griffiths, Jack; Fraser, James; Kirkus, Mindaugas; Chen, Hu; Nielsen, Christian; McCulloch, Iain

2017-01-01

Perovskite solar cells are one of the most promising photovoltaic technologies, due to their rapid increase in power conversion efficiency (3.8% to 21.1%) in a very short period of time and the relative ease of their fabrication compared to traditional inorganic solar cells. One of the drawbacks of perovskite solar cells is their limited stability in non-inert atmospheres. In the inverted device configuration this lack of stability can be attributed to the inclusion of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate(PEDOT:PSS) as the hole transporting layer. Herein we report the synthesis of two new triarylamine based hole transporting materials, synthesised from readily available starting materials. These new materials show increased power conversion efficiencies, of 13.0% and 12.1%, compared to PEDOT:PSS (10.9%) and exhibit increased stability achieving lifetimes in excess of 500 hours. Both molecules are solution processible at low temperatures and offer potential for low cost, scalable production on flexible substrates for large scale perovskite solar cells.

A facile micropatterning method for a highly flexible PEDOT:PSS on SU-8

KAUST Repository

Cho, Nam Chul

2016-04-17

We report the micropatterning of conducting polymer on the epoxy-based photoresist to demonstrate fully organic, conducting and flexible electrodes. We show that polystyrene sulfonic acid can be covalently linked to the surface of the photoresist (SU-8) by forming sulfonyl ester at the interfaces. We also present an application of the patterned PEDOT:PSS (poly(3,4-ethylenedioxythiophene) polystyrene sulfonate)/SU-8 to the electroplating of metal electrodes. © 2016 Elsevier B.V.

A facile micropatterning method for a highly flexible PEDOT:PSS on SU-8

KAUST Repository

Cho, Nam Chul; Diekhans, Justin; Steward, Malia; Bakr, Osman; Choi, Seungkeun

2016-01-01

We report the micropatterning of conducting polymer on the epoxy-based photoresist to demonstrate fully organic, conducting and flexible electrodes. We show that polystyrene sulfonic acid can be covalently linked to the surface of the photoresist (SU-8) by forming sulfonyl ester at the interfaces. We also present an application of the patterned PEDOT:PSS (poly(3,4-ethylenedioxythiophene) polystyrene sulfonate)/SU-8 to the electroplating of metal electrodes. © 2016 Elsevier B.V.

Influence of Parenting Styles on the Adolescent Students' Academic Achievement in Kenyan Day Secondary Schools

Science.gov (United States)

Odongo, Alice Atieno; Aloka, Peter J. O.; Raburu, Pamela

2016-01-01

The present study sought to establish the influence of parenting styles on adolescent academic achievement in day secondary schools in North Rachuonyo Sub-County, Kenya. Baumrind's theory of parenting style informed the study. The Concurrent Triangulation Design was used. The target population comprised 2409 day secondary students registered for…

Initial Teacher Education: Does Self-Efficacy Influence Candidate Teacher Academic Achievement and Future Career Performance?

Science.gov (United States)

Shawer, Saad F.

2013-01-01

This quantitative investigation examined the influence of low and high self-efficacy on candidate teacher academic performance in a foreign language teaching methodology course through testing the speculation that high self-efficacy levels would improve pedagogical-content knowledge (PCK). Positivism guided the research design at the levels of…

A first-in-man PET study of [18F]PSS232, a fluorinated ABP688 derivative for imaging metabotropic glutamate receptor subtype 5.

Science.gov (United States)

Warnock, Geoffrey; Sommerauer, Michael; Mu, Linjing; Pla Gonzalez, Gloria; Geistlich, Susanne; Treyer, Valerie; Schibli, Roger; Buck, Alfred; Krämer, Stefanie D; Ametamey, Simon M

2018-06-01

Non-invasive imaging of metabotropic glutamate receptor 5 (mGlu 5 ) in the brain using PET is of interest in e.g., anxiety, depression, and Parkinson's disease. Widespread application of the most widely used mGlu 5 tracer, [ 11 C]ABP688, is limited by the short physical half-life of carbon-11. [ 18 F]PSS232 is a fluorinated analog with promising preclinical properties and high selectivity and specificity for mGlu 5 . In this first-in-man study, we evaluated the brain uptake pattern and kinetics of [ 18 F]PSS232 in healthy volunteers. [ 18 F]PSS232 PET was performed with ten healthy male volunteers aged 20-40 years. Seven of the subjects received a bolus injection and the remainder a bolus/infusion protocol. Cerebral blood flow was determined in seven subjects using [ 15 O]water PET. Arterial blood activity was measured using an online blood counter. Tracer kinetics were evaluated by compartment modeling and parametric maps were generated for both tracers. At 90 min post-injection, 59.2 ± 11.1% of total radioactivity in plasma corresponded to intact tracer. The regional first pass extraction fraction of [ 18 F]PSS232 ranged from 0.41 ± 0.06 to 0.55 ± 0.03 and brain distribution pattern matched that of [ 11 C]ABP688. Uptake kinetics followed a simple two-tissue compartment model. The volume of distribution of total tracer (V T , ml/cm 3 ) ranged from 1.18 ± 0.20 for white matter to 2.91 ± 0.51 for putamen. The respective mean distribution volume ratios (DVR) with cerebellum as the reference tissue were 0.88 ± 0.06 and 2.12 ± 0.10, respectively. The tissue/cerebellum ratios of a bolus/infusion protocol (30/70 dose ratio) were close to the DVR values. Brain uptake of [ 18 F]PSS232 matched the distribution of mGlu 5 and followed a two-tissue compartment model. The well-defined kinetics and the possibility to use reference tissue models, obviating the need for arterial blood sampling, make [ 18 F]PSS232 a promising fluorine-18 labeled

Personal factors that influence deaf college students' academic success.

Science.gov (United States)

Albertini, John A; Kelly, Ronald R; Matchett, Mary Karol

2012-01-01

Research tells us that academic preparation is key to deaf students' success at college. Yet, that is not the whole story. Many academically prepared students drop out during their first year. This study identified entering deaf college students' personal factors as assessed by their individual responses to both the Noel-Levitz College Student Inventory Form B and the Learning and Study Strategies Inventory, second edition (LASSI). Entering students in 3 successive cohorts (total n =437) participated in this study. Results show that in addition to entry measurements of reading and mathematic skills, personal factors contributed to the academic performance of students in their first quarter in college. The Noel-Levitz provided the comparatively better predictive value of academic performance: Motivation for Academic Study Scale (e.g., desire to finish college). The LASSI also showed statistically significant predictors, the Self-Regulation Component (e.g., time management) and Will Component (e.g., self-discipline), but accounted for relatively less variability in the students' initial grade point averages. For this group of underprepared students, results show that personal factors can play a significant role in academic success. Deaf students' personal factors are discussed as they relate to other first-year college students and to their subsequent academic performance and persistence.

p-PEDOT:PSS as a heterojunction partner with n-ZnO for detection of LPG at room temperature

Energy Technology Data Exchange (ETDEWEB)

Ladhe, R.D. [Thin Film and Nano Science Laboratory, Department of Physics, School of Physical Sciences, North Maharashtra University, Jalgaon 425 001 (M.S.) (India); Gurav, K.V. [Department of Materials Science and Engineering, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Pawar, S.M. [Solar Cell Laboratory, LG Components R and D Center, 1271, Sa-Dong, Sanggrok-gu, Ansan-si, Gyeonggi-do 426-791 (Korea, Republic of); Kim, J.H. [Department of Materials Science and Engineering, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Sankapal, B.R., E-mail: brsankapal@rediffmail.com [Thin Film and Nano Science Laboratory, Department of Physics, School of Physical Sciences, North Maharashtra University, Jalgaon 425 001 (M.S.) (India)

2012-02-25

Highlights: Black-Right-Pointing-Pointer Formation of heterojunction n-ZnO and p-PEDOT:PSS at room temperature (27 Degree-Sign C). Black-Right-Pointing-Pointer Use of this heterojunction as room temperature LPG sensor. Black-Right-Pointing-Pointer Remarkable gas response with good stability of the sensing device. Black-Right-Pointing-Pointer Use of heterojunction could offer cost-effective LPG sensor that is ecological-friendly. Black-Right-Pointing-Pointer The mass production using scalable room temperature chemical deposition process. - Abstract: Investigation towards the performance of room temperature (27 Degree-Sign C) liquefied petroleum gas (LPG) sensor based on the heterojunction between p-PEDOT:PSS and n-type ZnO is reported. The junction was developed by using chemically deposited ZnO film on to fluorine doped tin oxide (FTO) coated glass substrate followed by coating of thin slurry layer of PEDOT:PSS by using spin coating technique. Both these methods are simple, inexpensive and suitable for large area applications. Different characterization techniques were used to characterize structural, surface morphological and compositional of the material deposited. LPG sensing behavior of the heterojunction was studied at room temperature along with the stability studies. At room temperature, the heterojunction showed 58.8% sensitivity upon exposure to 1000 ppm of LPG with good response and recovery time like 225 s and 190 s, respectively. Furthermore, the LPG sensor reported is cost-effective, user friendly, and easy to fabricate using low cost chemical methods at room temperature.

Measuring Malaysia School Resource Centers' Standards through iQ-PSS: An Online Management Information System

Science.gov (United States)

Zainudin, Fadzliaton; Ismail, Kamarulzaman

2010-01-01

The Ministry of Education has come up with an innovative way to monitor the progress of 9,843 School Resource Centers (SRCs) using an online management information system called iQ-PSS (Quality Index of SRC). This paper aims to describe the data collection method and analyze the current state of SRCs in Malaysia and explain how the results can be…

How Do Supports from Parents, Teachers, and Peers Influence Academic Achievement of Twice-Exceptional Students

Science.gov (United States)

Wang, Clare Wen; Neihart, Maureen

2015-01-01

This study investigated how perceived external factors such as supports from parents and teachers, and influences from peers contributed to the academic successes and failures of Singaporean twice-exceptional (2e) students. A total of six 2e participants from one secondary school in Singapore voluntarily participated in the study. This study used…

The Influence of Parents Educational Level on Secondary School Students Academic Achievements in District Rajanpur

Science.gov (United States)

Khan, Rana Muhammad Asad; Iqbal, Nadeem; Tasneem, Saima

2015-01-01

This study was conducted to focus the influence and impact of parents educational level on students academic achievement at secondary level of education. The study utilizes the students results of the 9th class in secondary school certificate examination taken by the Board of Intermediate & Secondary Education Dera Ghazi Khan. Oral interview,…

Influence of Emotional Intelligence and Need for Achievement on Interpersonal Relations and Academic Achievement of Undergraduates

Science.gov (United States)

Afolabi, Olukayode Ayooluwa; Ogunmwonyi, Edosa; Okediji, Abayomi

2009-01-01

This study examined influence of emotional intelligence and need for achievement on interpersonal relations and academic achievement of undergraduates. Questionnaires were administered to one hundred and ten (110) subjects. The independent variables are emotional intelligence and need for achievement, while the dependent variables are…

Development of a Flexible Strain Sensor Based on PEDOT:PSS for Thin Film Structures

Directory of Open Access Journals (Sweden)

Alexandra El Zein

2017-06-01

Full Text Available The aim of this study was to develop and optimize a reproducible flexible sensor adapted to thin low-density polyethylene (LDPE films and/or structures to enable their deformation measurements. As these deformations are suspected to be weak (less than 10%, the developed sensor needs to be particularly sensitive. Moreover, it is of prime importance that sensor integration and usability do not modify the mechanical behavior of its LDPE substrate. The literature review allowed several materials to be investigated and an elastomer/intrinsically conductive polymer PEDOT:PSS (CleviosTM filled composite was selected to simultaneously combine mechanical properties and electrical conductivity. This composite (made of PEDOT:PSS and silicone Bluesil® presented satisfying compatibilities with piezoresistive effects, negative temperature performances (in a range from −60 °C to 20 °C, as well as elongation properties (until the elastic limit of the substrate was reached. The method used for creating the sensor is fully described, as are the optimization of the sensor manufacture in terms of used materials, the used amount of materials where the percolation theory aspects must be considered, the adhesion to the substrate, and the manufacturing protocol. Electromechanical characterization was performed to assess the gauge factor (K of the sensor on its substrate.

Computer Anxiety, Academic Stress, and Academic Procrastination on College Students

Directory of Open Access Journals (Sweden)

Wahyu Rahardjo

2013-01-01

Full Text Available Academic procrastination is fairly and commonly found among college students. The lack of understanding in making the best use of computer technology may lead to anxiety in terms of operating computer hence cause postponement in completing course assignments related to computer operation. On the other hand, failure in achieving certain academic targets as expected by parents and/or the students themselves also makes students less focused and leads to tendency of postponing many completions of course assignments. The aim of this research is to investigate contribution of anxiety in operating computer and academic stress toward procrastination on students. As much as 65 students majoring in psychology became participants in this study. The results showed that anxiety in operating computer and academic stress play significant role in influencing academic procrastination among social sciences students. In terms of academic procrastination tendencies, anxiety in operating computer and academic stress, male students have higher percentage than female students.

Asian American women in science, engineering, and mathematics: Background contextual and college environment influences on self-efficacy and academic achievement

Science.gov (United States)

Vogt, Kristen E.

2005-07-01

The purpose of this research study was to examine, for undergraduate women of various Asian American ethnic backgrounds, the influence of background contextual and college environment factors on their sense of academic self-efficacy and achievement in science, technology, engineering, and mathematics (STEM) majors. Social cognitive career theory and its critiques provided a theoretical foundation for relationships from past performance, socioeconomic status, acculturation, and college environment variables (compositional diversity, racial climate, gendered climate, academic peer support), to academic self-efficacy and achievement. Data were collected through an online survey. Instrumentation included the scales of Language, Identity, and Behavioral Acculturation; Gender Discrimination; Faculty and Classroom Behavior; Interactions with Peers; and Academic Milestones Self-efficacy. The participants were 228 Asian American undergraduate women in STEM at a large public, doctoral research extensive university on the east coast; the response rate was 51%. In three MANOVAs for nine social cognitive career variables, four ethnic groups (East, South, Southeast, and Multi-ethnic Asian American) significantly differed only on socioeconomic status. In path analysis, the initial model was not a good fit and was rejected. The model was respecified through statistical and theoretical evaluation, tested in exploratory analysis, and considered a good fit. The respecified model explained 36% of semester GPA (achievement) and 28% of academic self-efficacy. The academic achievement of Asian American women in STEM was related to past performance, background contextual factors, academic self-efficacy, academic peer support, and gendered climate. The strongest direct influence on achievement was academic self-efficacy followed by past performance. The total effect of Asian acculturation on achievement was negative and the total effect of American acculturation on achievement was not

How do academic stress and leisure activities influence college students' emotional well-being? A daily diary investigation.

Science.gov (United States)

Zhang, Jieting; Zheng, Yao

2017-10-01

China has one of the largest bodies of college students who face growing academic stress that influences their well-being. Using a daily diary method in a group of Chinese college students (n = 139, mean age = 19.50 years, 27% males) who reported their daily positive and negative emotion consecutively for two weeks, this study investigated the dynamic relations between daily academic stress, leisure activities engagement, and emotion, and further examined the moderation of sex on these links. The results showed that at both between- and within-person level, academic stress was positively associated with negative emotion, and leisure activities engagement was positively associated with positive emotion. The association between leisure activities engagement and positive emotion were stronger among female students than among male students. These results suggest that effectively reducing academic stress and actively engaging in leisure activities are both important in promoting and enhancing daily emotional well-being. Copyright © 2017. Published by Elsevier Ltd.

Adaptação cultural e validação para a língua portuguesa da Parental Stress Scale: Neonatal Intensive Care Unit (PSS:NICU Adaptación cultural y validación al idioma português del Parental Stress Scale: Neonatal Intensive Care Unit (PSS:NICU Cultural adaptation and validation for the portuguese language of the Parental Stress Scale: Neonatal Intensive Care Unit (PSS:NICU

Directory of Open Access Journals (Sweden)

Sandra Regina de Souza

2012-01-01

Full Text Available OBJETIVO: Traduzir, realizar a adaptação cultural e validar a escala Parental Stress Scale:Neonatal Intensive Care Unit (PSS:NICU para a língua portuguesa. MÉTODOS: Utilizou-se o método descritivo de validação de instrumentos de medida, baseado nas etapas propostas por Guillemin et al. A análise da confiabilidade foi realizada por meio dos testes e retestes e da consistência interna. Na validação clínica, participaram 163 pais de recém-nascidos internados em Unidade de Terapia Intensiva Neonatal (UTIN. RESULTADOS: Os coeficientes de correlação intraclasse ficaram em torno de 0,70 mostrando boa estabilidade entre as duas avaliações. A análise fatorial pelo método de componentes principais utilizou os mesmos critérios da escala original, com rotação Varimax, com grau de variância adequado de 57,9%. Os maiores níveis de estresse dos pais foram obtidos na subescala "alteração do papel de pais". CONCLUSÃO: A PSS:NICU na versão em português é uma ferramenta válida e confiável para avaliação do estresse de pais com filho internado na UTIN.OBJETIVO: Traducir, realizar la adaptación cultural y validar la escala Parental Stress Scale:Neonatal Intensive Care Unit (PSS:NICU al idioma portugués. MÉTODOS: Se utilizó el método descriptivo de validación de instrumentos de medida, basado en las etapas propuestas por Guillemin et al. El análisis de la confiabilidad fue realizado por medio de los tests y retests y de la consistencia interna. En la validación clínica, participaron 163 padres de recién nacidos internados en una Unidad de Cuidados Intensivos Neonatal (UCIN. RESULTADOS: Los coeficientes de correlación intraclase quedaron alrededor de 0,70 mostrando buena estabilidad entre las dos evaluaciones El análisis factorial por el método de componentes principales utilizó los mismos criterios de la escala original, con rotación Varimax, con grado de varianza adecuado de 57,9%. Los mayores niveles de estrés de

Factors influencing the academic motivation of individual college students.

Science.gov (United States)

Yoshida, Masahiro; Tanaka, Masaaki; Mizuno, Kei; Ishii, Akira; Nozaki, Kumi; Urakawa, Ayako; Cho, Yuki; Kataoka, Yosky; Watanabe, Yasuyoshi

2008-10-01

Motivation is an important psychological concept in academic learning. Subjects performed jigsaw puzzle and square puzzle sessions (as difficulty variant task) and 80%, 50%, and 20% completion sessions (as completion variant task). After square puzzle or 20% completion sessions, subjective motivation decreased. Although baseline scores on an academic motivation scale were negatively correlated with changes in subjective motivation for the square puzzle session, a positive correlation was observed for the 20% completion session. These suggest that while continual completion of facile task trials may support the motivation of college students with lower academic motivation, attempting difficult task trials may sustain that of those with higher academic motivation.

The Influence of the College Environment and Student Involvement on First-Year Academic Self-Concept

Science.gov (United States)

Stocksdale, Brent

2015-01-01

Enhancing the self-beliefs of college students--in particular, academic self-concept--has been suggested as one way to enhance college student success. However, the literature on the influence of college often does not clearly identify nor effectively assess the type of self-belief being investigated, and little remains known as to how and when…

Peer relationships and academic achievement

Directory of Open Access Journals (Sweden)

Krnjajić Stevan B.

2002-01-01

Full Text Available After their childhood, when children begin to establish more intensive social contacts outside family, first of all, in school setting, their behavior i.e. their social, intellectual, moral and emotional development is more strongly affected by their peers. Consequently, the quality of peer relationships considerably affects the process of adaptation and academic achievement and their motivational and emotional attitude towards school respectively. Empirical findings showed that there is bi-directional influence between peer relationships and academic achievement. In other words, the quality of peer relationships affects academic achievement, and conversely, academic achievement affects the quality of peer relationships. For example, socially accepted children exhibiting prosocial, cooperative and responsible forms of behavior in school most frequently have high academic achievement. On the other hand, children rejected by their peers often have lower academic achievement and are a risk group tending to delinquency, absenteeism and drop out of school. Those behavioral and interpersonal forms of competence are frequently more reliable predictors of academic achievement than intellectual abilities are. Considering the fact that various patterns of peer interaction differently exert influence on students' academic behavior, the paper analyzed effects of (a social competence, (b social acceptance/rejection, (c child's friendships and (d prosocial behavior on academic achievement.

Examining reciprocal influences among family climate, school attachment, and academic self-regulation: Implications for school success.

Science.gov (United States)

Xia, Mengya; Fosco, Gregory M; Feinberg, Mark E

2016-06-01

Guided by family systems and ecological theories, this study examined the multicontextual implications of family, school, and individual domains for adolescents' school success. The first goal of this study was to examine reciprocal influences among family climate, school attachment, and academic self-regulation (ASR) during the middle school years. The second goal was to test the relative impact of each of these domains on adolescents' school adjustment and academic achievement after the transition to high school. We applied a cross-lag structural equation modeling approach to longitudinal data from 979 students in the 6th grade and their families, followed over 5 measurement occasions, from 6th through 9th grade. Controlling for family income, parent education, and adolescent gender, the results revealed reciprocal relationships between the family climate and school attachment over time; both of these factors were related to increases in ASR over time. In turn, ASR was a robust predictor of academic success, with unique associations with school adjustment and academic achievement. Family climate and school adjustment had modest to marginal associations with school adjustment, and no association with academic achievement. Applications of these findings for family school interventions are discussed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

The influence of costs and benefits' analysis on service strategy formulation: Learnings from the shipping industry

DEFF Research Database (Denmark)

Pagoropoulos, Aris; Kjær, Louise Laumann; Andersen, Jakob Axel Bejbro

2017-01-01

. This paper assesses how the analysis of costs and benefits of Product-Service Systems (PSS) as servitized offerings influences the formulation of service strategies in the shipping industry. The study examines both the manufacturer and customer perspectives using two case studies from the shipping sector....... Life Cycle Costing (LCC) was used as a tool to assess the associated costs and benefits of two proposed PSS. Based on the results of the LCC, the drivers and barriers of the actual transformation processes were explored through workshops and interviews served to map the perspectives of both...

The Influence of Reciprocal interactions in the Family on Academic Performance among Secondary School Students in Kenya

Directory of Open Access Journals (Sweden)

Rael Achieng Ogwari

2014-08-01

Full Text Available This study aimed to investigate the influence of reciprocal interactions in the family on academic performance among secondary school students in Siaya District. Stratified and purposive sampling techniques were used to select the study participants. The sample comprised of a total of 243 students (154 boys and 89 girls drawn from 27 public coeducational schools in the district.  Data was collected using student questionnaires. The researchers’ judgment of the representativeness of the items in the questionnaire to the study topic was used to determine content validity of the instrument while Cronbach’s alpha coefficient was used to ascertain validity and reliability of the instrument. Linear regression analysis and one way Analysis of Variance were used to analyze data. The results revealed significant relationship between reciprocal interactions in the family and academic performance of students. There was positive correlation between parental expectation, autonomy granting, cross-sex behaviour and students’ academic performance. Siblings’ sex dyads and birth order were also found to correlate with students’ academic performance. The findings may be used by policy makers to sensitize parents and students on the significance of specific interactions in the family on academic performance.

How academic career and habits related to the school environment influence on academic performance in the physical education subject

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Vizuete Carrizosa, Manuel

2012-01-01

Full Text Available The main objective of this study was to analyze the degree of influence of some school habits and scholar trayectory on academic achievement in physical education (PE students in secondary education (ESO in the city of Badajoz. A total sample of 1197 students in compulsory secondary education 49.9% men, and 50.1% women, participated in the study. They spent a questionnaire filled out by the river questions about major school habits, of which eight variables were analyzed also included the final course in the subject of EF as a variable for analysis of academic performance. Through statistical analysis with ANOVA, Mann-Whitney U, and Kruskal Wallis H, there are significant differences in PE scores in all variables analyzed (p d».001, among which being repetitive, being truant, the time to read and study daily. In the variable environment perceived in class, there is a degree of significance (p d».05. Pupils who were repeaters, missing more classes or were delayed more times than read and studied less and earned a worse environment in their classes, are those who obtained poorer performance on EF.

Vice-Chancellors Influence on Academic Staff Intentions to Use ...

African Journals Online (AJOL)

kmacharia

adoption and diffusion of Learning Management System (LMS) by academic staff for ... of TAM, as a supportive framework for investigating the academic staff ... This definition includes university-wide information systems that embrace blended.

Handheld and automated ultrasonic spray deposition of conductive PEDOT:PSS films and their application in AC EL devices

NARCIS (Netherlands)

Ely, Fernando; Matsumoto, Agatha; Zoetebier, Bram; Peressinotto, Valdirene S.; Hirata, Marcelo Kioshi; de Sousa, Douglas A.; Maciel, Rubens

2014-01-01

In this contribution we explore the spray deposition technique to achieve smooth films based on the conductive polymer PEDOT:PSS. Two different spray systems were used and compared namely: (a) handheld airbrush and (b) automated ultrasonic spray system. For each system a number of parameters were

Schooling Background and Academic Academic Achievement of Agricultural Students

Directory of Open Access Journals (Sweden)

N. Jayakumar

2016-05-01

Full Text Available In our society academic achievement is considered as a key criterion to judge one’s total potentiality and capability. Academic achievement is seen as a students’ grade point averages in many academic settings. Academic achievement has become an index of students’ future in this highly competitive world and Agricultural education is no exception.  Hence it becomes necessary to find out the factors that determine better academic performance. In this context the present study had been carried out to find out the possible relationship between schooling background and academic achievement of agriculture students. The students admitted in Adhiparasakthi Agricultural College, Kalavai, Vellore between 1999 and 2009 formed the subjects of the study. Findings of the study revealed that determinants like gender, type of school and stream of education had a significant role in the academic achievement of the students. Medium of instruction in HSC did influence the academic achievement but not significantly. It was also found that students who performed well in their HSC did perform well in their undergraduate programme also. This confirms that previous educational outcomes are the most important indicators of student’s future achievement and schooling background has a significant role in academic achievement of students.

Comparing LCC with LCA to assess PSS sustainability: the case of the eco-box

DEFF Research Database (Denmark)

Chong, K.N.; Dreijer, L.S.; Howard, Thomas J.

2014-01-01

Product/Service-Systems strategies are increasingly proving to be a source of competitive advantage and environmental improvement for engineering companies, the main hypothesis being that PSS should allow to decouple functionality, user satisfaction and financial income on the one hand, from the ...... the total environmental impact of the function-delivering technology on the other. This paper describes an integration of Life Cycle Assessment (LCA) and Life Cycle Costing (LCC), in an attempt to see if the two life cycle elements are related....

Photovoltaic performance of hybrid ITO/PEDOT:PSS/n-SnS/Al solar cell structure

Science.gov (United States)

Jain, Priyal; Arun, P.

2016-07-01

The present paper discusses the performance of ITO/PEDOT:PSS/n-SnS/Al structured solar cells fabricated by thermal evaporation. The performance characterizing parameters such as the open circuit voltage, short circuit current density, series resistance, parallel resistance, ideality factor and the overall efficiency were found to be dependent on the SnS grain size in the nano-meter regime and incident light intensity. The experimental work directly reconfirms the theoretical results and ideas raised in the literature by early researchers.

Liquid electrolyte positioning along the device channel influences the operation of Organic Electro-Chemical Transistors

KAUST Repository

D'angelo, Pasquale; Coppedè , Nicola; Tarabella, Giuseppe; Romeo, Agostino; Gentile, Francesco T.; Iannotta, Salvatore; Di Fabrizio, Enzo M.; Mosca, Roberto

2014-01-01

In this work, we show the influence of the liquid electrolyte adsorption by porous films made of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate), PEDOT:PSS, on the operation of an Organic Electro-Chemical Transistor with an active channel

Characterization of Piezoresistive PEDOT:PSS Pressure Sensors with Inter-Digitated and Cross-Point Electrode Structures

OpenAIRE

Wang, Jer-Chyi; Karmakar, Rajat; Lu, Yu-Jen; Huang, Chiung-Yin; Wei, Kuo-Chen

2015-01-01

The piezoresistive characteristics of poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) pressure sensors with inter-digitated (IDE) and cross-point electrode (CPE) structures have been investigated. A small variation of the resistance of the pressure sensors with IDE without bottom indium-tin-oxide (b-ITO) film and with CPE structures was observed owing to the single carrier-conducting pathway. For the IDE pressure sensors with b-ITO, the piezoresistive characteristics at low...

Investigating the Effect of Academic Procrastination on the Frequency and Variety of Academic Misconduct: A Panel Study

Science.gov (United States)

Patrzek, Justine; Sattler, Sebastian; van Veen, Floris; Grunschel, Carola; Fries, Stefan

2015-01-01

In prior studies, academic procrastination has been discussed as an influencing factor of academic misconduct. However, empirical studies were conducted solely cross-sectionally and investigated only a few forms of academic misconduct. This large scale web-based study examined the responses of between 1359 and 2207 participants from different…

Structural Modeling for Influence of Mathematics Self-Concept, Motivation to Learn Mathematics and Self-Regulation Learning on Mathematics Academic Achievement

OpenAIRE

Hamideh Jafari Koshkouei; Ahmad Shahvarani; Mohammad Hassan Behzadi; Mohsen Rostamy-Malkhalifeh

2016-01-01

The present study was carried out to investigate the influence of mathematics self-concept (MSC), motivation to learn mathematics (SMOT) and self-regulation learning (SRL) on students' mathematics academic achievement. This study is of a descriptive survey type. 300 female students at the first grade of high school (the second period) in City Qods, were selected by multiple step cluster sampling method and completed MSC, SMOT and SRL questionnaires. Mathematics academic achievement was measur...

The Influence Of Parental Background On Academic Performance Of ...

African Journals Online (AJOL)

It was hypothesized that there is no significant difference between the academic performance of students from high socio-economic status background and those from low SES backgrounds, also there is no significant difference between the academic performance of students form intact homes and the broken homes.

Profit enhancement by a set of performance and robustness indices based design of dual-dimensional PODC and PSS2B in smart grids

International Nuclear Information System (INIS)

Shayeghi, H.; Hashemi, Y.

2014-01-01

Highlights: • Design based on a set of performance and robustness criteria can increase profit. • Time delay as uncertainty in smart grid decrease profit. • Design method applied in this paper deal with large structure of controllers. • INSGA-II optimization and FDM method is applied to specify the best solution. - Abstract: Expansion of power systems is accompanied by innovations in smart grid solutions to power system operation and control. Profit enhancement by power oscillation damping controllers (PODC) and acceleration based power system stabilizer (PSS), model PSS2B, designed by the idea of pseudo-spectra based on multi-objective optimization is presented. The contribution of multi-objective functions in respect of performance and robustness criteria in stability enhancement is evaluated by considering the control actions of PODC and PSS2B as an ancillary service (AS). The robustness requirement is achieved by using the idea of pseudo-spectra to handle the changes of power system parameters and time delay introduced by processing of remote signals in the wide-area supplementary damping controller (WASDC). The weighted sum of six objective functions as performance and robustness criteria is selected as low-frequency oscillation damping index (LFODI). Two scenarios for the evaluation of small signal stability as an AS provided by PODC and PSS2B are considered. A multi-objective optimization approach based on LFODI, generation costs is formulated and improved non-dominated sorting genetic algorithm-II (INSGA-II) is employed to solve this problem. Fuzzy decision making (FDM) is used to find the best compromise solution from the set of Pareto-solution obtained by INSGA-II. Comparative analysis of the results of the conventional method and the proposed design method is presented by case study on a modified 2-area 4-machine power system

Interfacial micropore defect formation in PEDOT:PSS-Si hybrid solar cells probed by TOF-SIMS 3D chemical imaging.

Science.gov (United States)

Thomas, Joseph P; Zhao, Liyan; Abd-Ellah, Marwa; Heinig, Nina F; Leung, K T

2013-07-16

Conducting p-type polymer layers on n-type Si have been widely studied for the fabrication of cost-effective hybrid solar cells. In this work, time-of-flight secondary ion mass spectrometry (TOF-SIMS) is used to provide three-dimensional chemical imaging of the interface between poly(3,4-ethylene-dioxythiophene):polystyrenesulfonate (PEDOT:PSS) and SiOx/Si in a hybrid solar cell. To minimize structural damage to the polymer layer, an Ar cluster sputtering source is used for depth profiling. The present result shows the formation of micropore defects in the interface region of the PEDOT:PSS layer on the SiOx/Si substrate. This interfacial micropore defect formation becomes more prominent with increasing thickness of the native oxide layer, which is a key device parameter that greatly affects the hybrid solar cell performance. Three-dimensional chemical imaging coupled with Ar cluster ion sputtering has therefore been demonstrated as an emerging technique for probing the interface of this and other polymer-inorganic systems.

The Influence of Academic Tracking on Adolescent Social Networks

Science.gov (United States)

Fisher, Kim W.; Shogren, Karrie A.

2016-01-01

This study examined adolescents' social capital, through social network analyses (i.e., ego network analyses), in two high schools where students were placed into academic tracks adopted by the schools and shaped by disability status (i.e., general education, co-taught, segregated special education classrooms). The impact of academic tracks, as…

Deepening Our Understanding of Academic Inbreeding Effects on Research Information Exchange and Scientific Output: New Insights for Academic Based Research

Science.gov (United States)

Horta, Hugo

2013-01-01

This paper analyzes the impact of academic inbreeding in relation to academic research, and proposes a new conceptual framework for its analysis. We find that mobility (or lack of) at the early research career stage is decisive in influencing academic behaviors and scientific productivity. Less mobile academics have more inward oriented…

Academic Functioning and Peer Influences: A Short-Term Longitudinal Study of Network-Behavior Dynamics in Middle Adolescence

Science.gov (United States)

Rambaran, J. Ashwin; Hopmeyer, Andrea; Schwartz, David; Steglich, Christian; Badaly, Daryaneh; Veenstra, René

2017-01-01

In this study, the associations between peer effects and academic functioning in middle adolescence (N = 342; 14-15 years old; 48% male) were investigated longitudinally. Similarity in achievement (grade point averages) and unexplained absences (truancy) was explained by both peer selection and peer influence, net of acceptance, and connectedness.…

Psychological Factors Influencing Life Satisfaction of Undergraduates

OpenAIRE

Ajayi, Olubukola; Adewumi, Bukunmi

2017-01-01

This study was designed to assess the psychological factors influencing life satisfaction of undergraduates. The instruments used were Perceived Stress Scale (PSS), Wong and Law Emotional Intelligence Scale (WLEIS), Rosenberge Self-esteem Scale (RSS), and Satisfaction with Life Scale (SWLS). A total number of 190 participants were purposively selected across various faculties in Ekiti State University. Four hypotheses were tested using Independent t-test to find the effects of perceived stres...

One-pot preparation of PEDOT:PSS-reduced graphene decorated with Au nanoparticles for enzymatic electrochemical sensing of H{sub 2}O{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Mercante, Luiza A., E-mail: lamercante@gmail.com [National Laboratory for Nanotechnology in Agribusiness (LNNA), Embrapa Instrumentation, 13560-970, São Carlos, SP (Brazil); Facure, Murilo H.M. [National Laboratory for Nanotechnology in Agribusiness (LNNA), Embrapa Instrumentation, 13560-970, São Carlos, SP (Brazil); Center for Exact Sciences and Technology, Federal University of São Carlos (UFSCar), 13565-905, São Carlos, SP (Brazil); Sanfelice, Rafaela C.; Migliorini, Fernanda L.; Mattoso, Luiz H.C. [National Laboratory for Nanotechnology in Agribusiness (LNNA), Embrapa Instrumentation, 13560-970, São Carlos, SP (Brazil); Correa, Daniel S., E-mail: daniel.correa@embrapa.br [National Laboratory for Nanotechnology in Agribusiness (LNNA), Embrapa Instrumentation, 13560-970, São Carlos, SP (Brazil); Center for Exact Sciences and Technology, Federal University of São Carlos (UFSCar), 13565-905, São Carlos, SP (Brazil)

2017-06-15

Highlights: • Hybrid ternary nanocomposite PEDOT:PSS-rGO-AuNPs is developed by a one-step approach. • Horseradish peroxidase is used to build a novel hybrid biomaterial. • The PEDOT:PSS-rGO-AuNPs-HRP displays excellent electrochemical activity toward the reduction of H{sub 2}O{sub 2}. • A significant low detection limit of 0.08 μM and wider linear range is achieved. • The constructed electrode is used detecting H{sub 2}O{sub 2} in real samples. - Abstract: The development of novel graphene-based nanocomposites is a hotspot in materials science due to their unique optical, electronic, thermal, mechanical and catalytic properties for varied applications. The present work reports on the development of a graphene-based ternary nanocomposite of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate), reduced graphene oxide and gold nanoparticles (PEDOT:PSS-rGO-AuNPs) for the detection of hydrogen peroxide (H{sub 2}O{sub 2}). The hybrid nanocomposite showed superior electrochemical properties and higher stability compared to each individual component as electrode materials, showing a synergistic effect between PEDOT, rGO and AuNPs. The nanocomposite was obtained via a facile one-step approach and was assembly with horseradish peroxidase (HRP). The PEDOT:PSS-rGO-AuNPs-HRP modified electrode has been used for the amperometric detection of H{sub 2}O{sub 2} and exhibited a high sensitivity of up to 677 μA mM{sup −1} cm{sup −2}, with a wide linear range from 5 to 400 μM and a low detection limit of 0.08 μM (S/N = 3). This developed enzymatic biosensor showed to be highly stable and unresponsive to potentially interfering substances, and it could be used for sensing H{sub 2}O{sub 2} in real samples, including tap water and bovine milk samples. These enhanced sensing performance could be ascribed to the intimate contact of AuNPs onto the rough surface of the PEDOT:PSS-rGO nanocomposite, which has a high electrical conductivity and large surface area, providing

Influence of Counselling Services on Perceived Academic Performance of Secondary School Students in Lagos State

Directory of Open Access Journals (Sweden)

Foluke Nike Bolu-Steve

2017-04-01

Full Text Available This study aimed at looking at the influence of counseling services on perceived academic performance of secondary school students in Lagos State. At the first stage, the researchers purposively selected Ikorodu L.G.A in Lagos State. At the researchers selected two schools (1 Private schools, & 1 Public schools, using simple random technique. Thus, a total of two schools were picked in each of the L.G.A. Finally, simple random sampling was used in selecting eighty students in each L.G.A, thus making a total of two hundred and forty Senior Secondary students that participated in the study. Six hypotheses were generated for the purpose of this study. Data were gathered using a researcher designed instrument tagged “Influence of Counselling Service on Academic Performance of Students Questionnaire (ICAPSQ. The findings of this study showed that there was no significant difference on the basis of age, class level and school type. However a significant difference was found on the basis of respondent’s religion, gender and the number of times the students visited the counselor. It was therefore recommended that the ministry of education should ensure that guidance and counselling units are established in all public and private secondary schools in Nigeria.

Monolayer WS{sub 2} crossed with an electro-spun PEDOT-PSS nano-ribbon: Fabricating a Schottky diode

Energy Technology Data Exchange (ETDEWEB)

Ortiz, Deliris N.; Vedrine, Josee [Department of Physics and Electronics, University of Puerto Rico-Humacao, Humacao, PR 00791 (United States); Pinto, Nicholas J., E-mail: nicholas.pinto@upr.edu [Department of Physics and Electronics, University of Puerto Rico-Humacao, Humacao, PR 00791 (United States); Naylor, Carl H.; Charlie Johnson, A.T. [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 (United States)

2016-12-15

Highlights: • First report on a Schottky diode formed from monolayer WS{sub 2} and PEDOT-PSSA nano-ribbon. • Straightforward and unique fabrication technique. • Diode operation is stable in air. - Abstract: WS{sub 2} and PEDOT-PSS were individually characterized with the goal of analyzing charge transport across a hetero-junction formed by these two materials. In thermal equilibrium electron flow from the WS{sub 2} conduction band into the polymer LUMO level leads to band bending that creates a potential barrier preventing further current. The measured current-voltage (I{sub DS}-V{sub DS}) curve across the hetero-junction was non-linear and asymmetric similar to a diode, with a turn-on voltage of 1.4 V and a rectification ratio of 12. The device I–V data were analyzed using the standard thermionic emission model of a Schottky junction and yielded an ideality parameter of 1.9 and a barrier height of 0.58 eV. This facile technique is the first report on a nano-diode fabricated using WS{sub 2} and PEDOT-PSS, opening up the possibility of extending this work to include other layered transition metal dichalcogenides and conducting polymers.

From academic research articles to academic visual and video essays: Only a multimodal transition?

DEFF Research Database (Denmark)

Maier, Carmen Daniela

Drawing on an interdisciplinary theoretical framework, we propose to examine multimodal texts from the academic genre set belonging to the field of presenting and discussing research results: the academic research article, the academic visual essay and the academic video essay. The data...... for this study has been collected from academic journals that belong to print medium and to multimedia. In order to articulate an analytical model for the description and interpretation of these subgenres, we depart from the understanding of genres as linguistic categories influenced by specific situations...... subgenres will also be facilitated by applying theoretical approaches focused on knowledge communication because the academic discourse in these subgenres is based on specific meaning-making structures. The fact that these structures are linked to the subgenres’ common communicative purpose of representing...

Capacitated vehicle routing problem for PSS uses based on ubiquitous computing: An emerging markets approach

OpenAIRE

Alberto Ochoa-Ortíz; Francisco Ornelas-Zapata; Lourdes Margain-Fuentes; Miguel Gastón Cedillo-Campos; Jöns Sánchez-Aguilar; Rubén Jaramillo-Vacio; Isabel Ávila

2015-01-01

El problema de ruteo de vehículos bajo las limitaciones de capacidad y basado en computación ubicua desde una perspectiva relacionada con PSS (Producto-Servicio de Sistemas) para desarrollar configuraciones para el transporte urbano de mercancías es abordado. Éste trabajo considera las especificidades de la logística urbana bajo un contexto de mercados emergentes. En este caso, involucra: i) bajas competencias logísticas de los tomadores de decisiones; ii) la limitada disponibilidad de datos;...

Machine-Washable PEDOT:PSS Dyed Silk Yarns for Electronic Textiles.

Science.gov (United States)

Ryan, Jason D; Mengistie, Desalegn Alemu; Gabrielsson, Roger; Lund, Anja; Müller, Christian

2017-03-15

Durable, electrically conducting yarns are a critical component of electronic textiles (e-textiles). Here, such yarns with exceptional wear and wash resistance are realized through dyeing silk from the silkworm Bombyx mori with the conjugated polymer:polyelectrolyte complex PEDOT:PSS. A high Young's modulus of approximately 2 GPa combined with a robust and scalable dyeing process results in up to 40 m long yarns that maintain their bulk electrical conductivity of approximately 14 S cm -1 when experiencing repeated bending stress as well as mechanical wear during sewing. Moreover, a high degree of ambient stability is paired with the ability to withstand both machine washing and dry cleaning. For the potential use for e-textile applications to be illustrated, an in-plane thermoelectric module that comprises 26 p-type legs is demonstrated by embroidery of dyed silk yarns onto a piece of felted wool fabric.

Model Calibration of Exciter and PSS Using Extended Kalman Filter

Energy Technology Data Exchange (ETDEWEB)

Kalsi, Karanjit; Du, Pengwei; Huang, Zhenyu

2012-07-26

Power system modeling and controls continue to become more complex with the advent of smart grid technologies and large-scale deployment of renewable energy resources. As demonstrated in recent studies, inaccurate system models could lead to large-scale blackouts, thereby motivating the need for model calibration. Current methods of model calibration rely on manual tuning based on engineering experience, are time consuming and could yield inaccurate parameter estimates. In this paper, the Extended Kalman Filter (EKF) is used as a tool to calibrate exciter and Power System Stabilizer (PSS) models of a particular type of machine in the Western Electricity Coordinating Council (WECC). The EKF-based parameter estimation is a recursive prediction-correction process which uses the mismatch between simulation and measurement to adjust the model parameters at every time step. Numerical simulations using actual field test data demonstrate the effectiveness of the proposed approach in calibrating the parameters.

Entrepreneurship Education and Academic Performance

Science.gov (United States)

Johansen, Vegard

2014-01-01

The significant increase of entrepreneurship education (EE) is a trend in Europe. Entrepreneurship education is supposed to promote general and specific entrepreneurial abilities and improve academic performance. This paper evaluates whether EE influences academic performance, measured by Grade Point Average. The main indicator used for EE is the…

Nursing Faculty and Academic Integrity

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Wilson, Cecilia E.

2013-01-01

Insufficient information exists regarding the process influencing faculty decisions, specifically in the area of maintaining academic integrity in an online environment. The purpose of the study was to explore the experiences and decision-making process of nursing faculty related to maintaining academic integrity in an online environment. The…

Influence of Academic Self-Regulation, Critical Thinking, and Age on Online Graduate Students' Academic Help-Seeking

Science.gov (United States)

Dunn, Karee E.; Rakes, Glenda C.; Rakes, Thomas A.

2014-01-01

Academic help-seeking is an invaluable learning strategy that has not yet received much attention in the distance education research literature. The asynchronous nature of distance education and many online courses presents an inherent roadblock to help-seeking. The purpose of this study was to explore the effect of academic self-regulation,…

Rituximab Effectiveness and Safety for Treating Primary Sjögren's Syndrome (pSS: Systematic Review and Meta-Analysis.

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Francine Bertolais do Valle Souza

Full Text Available Primary Sjögren's Syndrome (pSS is a systemic autoimmune disease that involves the exocrine glands and internal organs. pSS leads to destruction and loss of secretory function due to intense lymphoplasmacytic infiltration. Therapeutic options include mainly symptomatic and supportive measures, and traditional immunosuppressant drugs have shown no effectiveness in randomized trials. Rituximab (RTX is a chimeric antibody anti-CD20 that leads to B cell depletion by diverse mechanisms. There is evidence that this drug may be effective for treating pSS. The objective of this systematic review was to evaluate Rituximab effectiveness and safety for treating pSS.We conducted a systematic review of RCTs published until December 2015, with no language restriction. We registered a protocol on Plataforma Brasil (40654814.6.0000.5505 and developed search strategies for the following scientific databases: MEDLINE, EMBASE, CENTRAL and LILACS. We included adults with established pSS diagnosis and considered the use of Rituximab as intervention and the use of other drugs or placebo as control. Four studies met our eligibility criteria: three with low risk of bias and one with uncertain risk of bias. The total number of participants was 276 (145 RTX, 131 placebo. We assessed the risk of bias of each included study and evaluated the following as primary outcomes: lacrimal gland function, salivary gland function, fatigue improvement and adverse events. We found no significant differences between the groups in the Schirmer test at week 24 meta-analysis (MD 3.59, 95% CI -2.89 to 10.07. Only one study evaluated the lissamine green test and reported a statistically significant difference between the groups at week 24 (MD -2.00, 95% CI -3.52 to -0.48. There was a significant difference between the groups regarding salivary flow rate (MD 0.09, 95% CI 0.02 to 0.16 and improvement in fatigue VAS at weeks 6 (RR 3.98, 95% CI 1.61 to 9.82 and week 16 (RR 3.08, 95% CI 1.21 to

An Evaluation Of Academic Stress And Coping Mechanism Among ...

African Journals Online (AJOL)

The study assessed and evaluated academic stress coping mechanisms adopted by married female students in Nigerian tertiary institutions. This was with the aim of exploring the influence of academic stress on married female students‟ academic performance and their coping strategies used to enhance their academic ...

Economical low-light photovoltaics by using the Pt-free dye-sensitized solar cell with graphene dot/PEDOT:PSS counter electrodes

KAUST Repository

Lee, Chuan Pei; Lin, Chin An; Wei, Tzu Chiao; Tsai, Meng Lin; Meng, Ying; Li, Chun Ting; Ho, Kuo Chuan; Wu, Chih I.; Lau, Shu Ping; He, Jr-Hau

2015-01-01

.14%). Without much impact on efficiency, the DSSCs with GD-PEDOT:PSS CEs work well under low-light conditions (light intensity <13.5mWcm and angle of incidence >60°), such as indoor and low-level outdoor lighting and of the sun while the other traditional cells

Predicting Intra-Individual Academic Achievement Trajectories of Adolescents Nested in Class Environment: Influence of motivation, implicit theory of intelligence, self-esteem and parenting

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Isabelle Roskam

2007-05-01

Full Text Available In a longitudinal study conducted on 1130 adolescents (557 male and 573 female in the 1st-6th grades from Belgian secondary schools, we tested the influence of individual factors (motivational constructs, implicit theory of intelligence and self-esteem and environmental determinants (parenting and class environment of academic achievement (grades in mathematics, language arts and GPA at three points in time. Using hierarchical linear models, we observed a decrease of grade over the course of the study, reciprocal relations between motivational constructs, self-esteem and academic achievement, a strong positive impact of supportive parenting and a moderate influence of class environment.

The Emotional Impact Nursing Faculty Experience in Relationship to Student Academic Dishonesty and the Social and Political Factors That Influence Their Decision to Report Dishonesty

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Scebold, Jody L.

2016-01-01

The purpose of the study was to explore the emotional impact nursing faculty experience in relationship to nursing student academic dishonesty and the social and political factors that influence their decision to report suspected acts of academic dishonesty. The study was based on Fontana's 2009 study titled "Nursing Faculty Experiences of…

Does learning style influence academic performance in different forms of assessment?

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Wilkinson, Tracey; Boohan, Mairead; Stevenson, Michael

2014-03-01

Educational research on learning styles has been conducted for some time, initially within the field of psychology. Recent research has widened to include more diverse disciplines, with greater emphasis on application. Although there are numerous instruments available to measure several different dimensions of learning style, it is generally accepted that styles differ, although the qualities of more than one style may be inherent in any one learner. But do these learning styles have a direct effect on student performance in examinations, specifically in different forms of assessment? For this study, hypotheses were formulated suggesting that academic performance is influenced by learning style. Using the Honey and Mumford Learning Style Questionnaire, learning styles of a cohort of first year medical and dental students at Queen's University Belfast were assessed. Pearson correlation was performed between the score for each of the four learning styles and the student examination results in a variety of subject areas (including anatomy) and in different types of assessments - single best answer, short answer questions and Objective Structured Clinical Examinations. In most of the analyses, there was no correlation between learning style and result and in the few cases where the correlations were statistically significant, they generally appeared to be weak. It seems therefore from this study that although the learning styles of students vary, they have little effect on academic performance, including in specific forms of assessment. © 2013 Anatomical Society.

Black males' self-perceptions of academic ability and gifted potential in advanced science classes

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Rascoe, Barbara; Monroe Atwater, Mary

2005-10-01

The purpose of this research effort was to examine Black male students' self-perceptions of academic ability and gifted potential in science. The purposeful sample consisted of nine Black males between the ages of 14 and 18 years. Four categories of self-perceptions of academic ability and gifted potential emerged from the data. These included: (a) gifted high achievers; (b) gifted could do better high achievers; (c) gifted could do better situational nonachievers; and (d) gifted could do better underachievers. Science teachers' influences that referenced participants' academic achievement pointed to validation. Participants' perceptions regarding how science teachers' influenced their academic performance focused on science teachers' content knowledge. Power dynamics germane to Black male participants' value or worth that directed their efforts in science learning environments are discussed. Implications are posited for science teaching, science education programs, and future research. This research endeavor was based on two premises. The first premise is that Black males' self-perceptions of academic ability affect their science academic achievement. The second premise is that, given parental, peer, and community influences, science teachers have considerable influence on students' self-perceptions of academic ability. However, the focus of this research was not on parental influences, peer influences, or any potential influences that participants' communities may have on their academic achievement.

The Influence of Academic Values on Scholarly Publication and Communication Practices. Research and Occasional Paper Series: CSHE.13.06

Science.gov (United States)

Harley, Diane; Earl-Novell, Sarah; Arter, Jennifer; Lawrence, Shannon; King, C. Judson

2006-01-01

This study reports on five disciplinary case studies that explore academic value systems as they influence publishing behavior and attitudes of University of California, Berkeley faculty. The case studies are based on direct interviews with relevant stakeholders--faculty, advancement reviewers, librarians, and editors--in five fields: chemical…

Academic Libraries in the Kingdom of Saudi Arabia.

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Tameem, Jamal A.

1988-01-01

Considers the status of higher education and academic libraries in Saudi Arabia. Topics covered include the role of academic libraries, use patterns, library education, the availability of professional librarians and administrators, library automation, academic cooperation with the United States, and the impact of social influences on library…

Drug consumption among medical students in São Paulo, Brazil: influences of gender and academic year.

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Oliveira, Lucio Garcia de; Barroso, Lucia Pereira; Wagner, Gabriela Arantes; Ponce, Julio de Carvalho; Malbergier, André; Stempliuk, Vladimir de Andrade; Andrade, Arthur Guerra de

2009-09-01

To analyze alcohol, tobacco and other drug use among medical students. Over a five-year period (1996-2001), we evaluated 457 students at the Universidade de São Paulo School of Medicine, located in São Paulo, Brazil. The students participated by filling out an anonymous questionnaire on drug use (lifetime, previous 12 months and previous 30 days). The influence that gender and academic year have on drug use was also analyzed. During the study period, there was an increase in the use of illicit drugs, especially inhalants and amphetamines, among the medical students evaluated. Drug use (except that of marijuana and inhalants) was comparable between the genders, and academic year was an important influencing factor. Increased inhalant use was observed among the medical students, especially among males and students in the early undergraduate years. This is suggestive of a specific behavioral pattern among medical students. Our findings corroborate those of previous studies. Inhalant use is on the rise among medical students at the Universidade de São Paulo School of Medicine. Because of the negative health effects of illicit drug use, further studies are needed in order to deepen the understanding of this phenomenon and to facilitate the development of preventive measures.

How Distorted Thinking Influence Arab Children Academic Achievement in Israel?

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Gith, Emad

2018-01-01

The purpose of the current study was to examine the relation between the parents Cognitive Distortion and Arab children academic achievements in Israel. 52 fifth grade Arab Children and their parents from Israel were participated. The results indicated that parent's cognitive distortion related negatively to children academic achievements; there…

A structural equation modelling of the academic self-concept scale

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Musa Matovu

2014-03-01

Full Text Available The study aimed at validating the academic self-concept scale by Liu and Wang (2005 in measuring academic self-concept among university students. Structural equation modelling was used to validate the scale which was composed of two subscales; academic confidence and academic effort. The study was conducted on university students; males and females from different levels of study and faculties. In this study the influence of academic self-concept on academic achievement was assessed, tested whether the hypothesised model fitted the data, analysed the invariance of the path coefficients among the moderating variables, and also, highlighted whether academic confidence and academic effort measured academic selfconcept. The results from the model revealed that academic self-concept influenced academic achievement and the hypothesised model fitted the data. The results also supported the model as the causal structure was not sensitive to gender, levels of study, and faculties of students; hence, applicable to all the groups taken as moderating variables. It was also noted that academic confidence and academic effort are a measure of academic self-concept. According to the results the academic self-concept scale by Liu and Wang (2005 was deemed adequate in collecting information about academic self-concept among university students.

Effect of Surface Morphology and Dispersion Media on the Properties of PEDOT:PSS/n-Si Hybrid Solar Cell Containing Functionalized Graphene

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Pham Van Trinh

2017-01-01

Full Text Available We present the results on the effect of surface morphology and dispersion media on the properties of PEDOT:PSS/n-Si hybrid solar cell containing functionalized graphene (Gr. The hybrid solar cells based on SiNWs showed higher power conversion efficiency (PCE compared to the planar based cells due to suppressing the carrier recombination and improving carrier transport efficiency. The PCE of hybrid solar cells could be improved by adding Gr into PEDOT:PSS. Different solvents including deionized (DI water, ethylene glycol (EG, and isopropyl alcohol (IPA were used as media for Gr dispersion. The best performance was obtained for the cell containing Gr dispersed in EG with a measured PCE of 7.33% and nearly 13% and 16% enhancement in comparison with the cells using Gr dispersed in IPA and DI water, respectively. The increase in PCE is attributed to improving the carrier-mobility, electrical conductivity, PEDOT crystallinity, and ordering.

Relationships between molecular structure and kinetic and thermodynamic controls in lipid systems. Part II: Phase behavior and transformation paths of SSS, PSS and PPS saturated triacylglycerols--effect of chain length mismatch.

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Bouzidi, Laziz; Narine, Suresh S

2012-01-01

The kinetic phase behavior and phase transformation paths of purified tristearoylglycerol (SSS), 3-palmitoyl-1,2-distearoyl-sn-glycerol (PSS) and 1,2-dipalmitoyl-3-stearoyl-sn-glycerol (PPS) were investigated in terms of polymorphism, crystallization and melting. The details of the phase transformation paths were obtained using the heating cycles of two sets of experiments: (a) cooling rate was varied and heating rate fixed and (b) cooling rate was fixed and heating rate varied. Kinetic effects were manifest in all measured properties, underscoring the complexity of the phase transformation paths for each TAG, and the intricate thermodynamics-molecular relationships. For the first time, XRD data obtained for SSS, PSS and PPS TAGs, cooled at rates higher than 0.5°C/min, suggested the formation of a transient structure similar to the so-called α(2)-phase which has been observed in mixed saturated-unsaturated TAGs quenched from the melt. The more stable phases (β' in PSS and PPS, and β in SSS) were only observed for cooling rates lower than 1.0°C/min. The kinetic and thermodynamic differences observed in the crystallization, structure and melting of SSS, PSS and PPS are proposed to be mainly due to the disturbances introduced at the "terrace" level via methyl-end group interactions, i.e., the missing of two or four CH(2) groups compared to SSS. The symmetrical SSS with a relatively flat "terrace" crystallizes preferably in the most stable β-form. Two missing CH(2) groups at the sn-1 position (PSS) introduces enough structural disturbances to promote the relative prevalence and persistence of the β'-phase, and four missing CH(2) groups at the sn-1 and sn-2 positions (PPS) is relatively too large of a disturbance and therefore favors the α-form. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Emotional Intelligence and Academic Anxieties: A Literature Review

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Jan, Sajjad Ullah; Anwar, Mumtaz Ali; Warraich, Nosheen Fatima

2017-01-01

Emotional intelligence is an important area of psychology, which has gained acceptance in almost every academic discipline. It also seems to influence the various academic activities undertaken by students. This article, which is part of a larger study, reviews the literature on emotional intelligence, and its relationship with the academic and…

Longitudinal influence of alcohol and marijuana use on academic performance in college students.

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Shashwath A Meda

Full Text Available Alcohol and marijuana are the two most abused substances in US colleges. However, research on the combined influence (cross sectional or longitudinal of these substances on academic performance is currently scant.Data were derived from the longitudinal 2-year Brain and Alcohol Research in College Students (BARCS study including 1142 freshman students who completed monthly marijuana use and alcohol consumption surveys. Subjects were classified into data-driven groups based on their alcohol and marijuana consumption. A linear mixed-model (LMM was employed using this grouping factor to predict grade point average (GPA, adjusted for a variety of socio-demographic and clinical factors.Three data-driven clusters emerged: 1 No/low users of both, 2 medium-high alcohol/no-low marijuana, and 3 medium-high users of both substances. Individual cluster derivations between consecutive semesters remained stable. No significant interaction between clusters and semester (time was noted. Post-hoc analysis suggest that at the outset, compared to sober peers, students using moderate to high levels of alcohol and low marijuana demonstrate lower GPAs, but this difference becomes non-significant over time. In contrast, students consuming both substances at moderate-to-high levels score significantly lower at both the outset and across the 2-year investigation period. Our follow-up analysis also indicate that when students curtailed their substance use over time they had significantly higher academic GPA compared to those who remained stable in their substance use patterns over the two year period.Overall, our study validates and extends the current literature by providing important implications of concurrent alcohol and marijuana use on academic achievement in college.

Longitudinal influence of alcohol and marijuana use on academic performance in college students.

Science.gov (United States)

Meda, Shashwath A; Gueorguieva, Ralitza V; Pittman, Brian; Rosen, Rivkah R; Aslanzadeh, Farah; Tennen, Howard; Leen, Samantha; Hawkins, Keith; Raskin, Sarah; Wood, Rebecca M; Austad, Carol S; Dager, Alecia; Fallahi, Carolyn; Pearlson, Godfrey D

2017-01-01

Alcohol and marijuana are the two most abused substances in US colleges. However, research on the combined influence (cross sectional or longitudinal) of these substances on academic performance is currently scant. Data were derived from the longitudinal 2-year Brain and Alcohol Research in College Students (BARCS) study including 1142 freshman students who completed monthly marijuana use and alcohol consumption surveys. Subjects were classified into data-driven groups based on their alcohol and marijuana consumption. A linear mixed-model (LMM) was employed using this grouping factor to predict grade point average (GPA), adjusted for a variety of socio-demographic and clinical factors. Three data-driven clusters emerged: 1) No/low users of both, 2) medium-high alcohol/no-low marijuana, and 3) medium-high users of both substances. Individual cluster derivations between consecutive semesters remained stable. No significant interaction between clusters and semester (time) was noted. Post-hoc analysis suggest that at the outset, compared to sober peers, students using moderate to high levels of alcohol and low marijuana demonstrate lower GPAs, but this difference becomes non-significant over time. In contrast, students consuming both substances at moderate-to-high levels score significantly lower at both the outset and across the 2-year investigation period. Our follow-up analysis also indicate that when students curtailed their substance use over time they had significantly higher academic GPA compared to those who remained stable in their substance use patterns over the two year period. Overall, our study validates and extends the current literature by providing important implications of concurrent alcohol and marijuana use on academic achievement in college.

Influences for Gender Disparity in Academic Neuroradiology.

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Ahmadi, M; Khurshid, K; Sanelli, P C; Jalal, S; Chahal, T; Norbash, A; Nicolaou, S; Castillo, M; Khosa, F

2018-01-01

There has been extensive interest in promoting gender equality within radiology, a predominately male field. In this study, our aim was to quantify gender representation in neuroradiology faculty rankings and determine any related factors that may contribute to any such disparity. We evaluated the academic and administrative faculty members of neuroradiology divisions for all on-line listed programs in the US and Canada. After excluding programs that did not fulfill our selection criteria, we generated a short list of 85 US and 8 Canadian programs. We found 465 faculty members who met the inclusion criteria for our study. We used Elsevier's SCOPUS for gathering the data pertaining to the publications, H-index, citations, and tenure of the productivity of each faculty member. Gender disparity was insignificant when analyzing academic ranks. There are more men working in neuroimaging relative to women (χ 2 = 0.46; P = .79). However, gender disparity was highly significant for leadership positions in neuroradiology (χ 2 = 6.76; P = .009). The median H-index was higher among male faculty members (17.5) versus female faculty members (9). Female faculty members have odds of 0.84 compared with male faculty members of having a higher H-index, adjusting for publications, citations, academic ranks, leadership ranks, and interaction between gender and publications and gender and citations (9). Neuroradiology faculty members follow the same male predominance seen in many other specialties of medicine. In this study, issues such as mentoring, role models, opportunities to engage in leadership/research activities, funding opportunities, and mindfulness regarding research productivity are explored. © 2018 by American Journal of Neuroradiology.

[Socio-economic and psycho-affective factors and their influence on academic performance of residents in Obstetrics and Gynecology].

Science.gov (United States)

Manterola Álvarez, David

2015-03-01

Academic performance is the mean objective of the teaching-learning process, but there are many other variables or factors outside the OB/GYN resident involved in this process, such as those related to the environment in which they operate, teachers, interaction with their peers, family, society, and many other factors contained individually, such as learning styles, motivation, study habits, personality traits, among others. Identify which are the main socio-economic and psycho-affective factors that influence on academic performance of residents in Obstetrics and Gynecology. Observational, cross-sectional quantitative, correlational and non-experimental study in Obstetrics and Gynecology residents of a public general hospital tertiary care. A type survey to obtain data and deepen personal and socioeconomic status of each resident instrument was designed. Females predominated with 15 cases and only 5 were male. Sixteen of medical residents claimed that having a good habit of sleep helps improve their academic performance and their performance in academic and healthcare activities. Fifteen felt that work much better with peers of the opposite sex. Ten felt that developing a type of self-directed learning contributes greatly to improve their performance and 19 felt that having a mentor during residency contributes to improve their academic performance. Fifteen reported being victim of abuse or discrimination from their peers. Sixteen claimed to have been very sad or depressed at some point during residency. Eight consumed alcohol and seven used tobacco to relax.

The Influence of Experience and Cognitive Style on International Entrepreneurial Intentions: The Contribution of Academic Education in this Relation

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Sommer, Lutz

2013-01-01

Introduction: The paper at hand examines the influence of Cognitive Style (CS) and International Experience (IE) on International Entrepreneurial Self-Efficacy (IESE) and International Entrepreneurial Intention (IEI) as well as the role of Academic Education (AE) in this context. Method: Based on a survey that was conducted among 111 students the…

Peace of Mind, Academic Motivation, and Academic Achievement in Filipino High School Students.

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Datu, Jesus Alfonso D

2017-04-09

Recent literature has recognized the advantageous role of low-arousal positive affect such as feelings of peacefulness and internal harmony in collectivist cultures. However, limited research has explored the benefits of low-arousal affective states in the educational setting. The current study examined the link of peace of mind (PoM) to academic motivation (i.e., amotivation, controlled motivation, and autonomous motivation) and academic achievement among 525 Filipino high school students. Findings revealed that PoM was positively associated with academic achievement β = .16, p amotivation β = -.19, p < .05, and autonomous motivation was positively associated with academic achievement β = .52, p < .01. Furthermore, the results of bias-corrected bootstrap analyses at 95% confidence interval based on 5,000 bootstrapped resamples demonstrated that peace of mind had an indirect influence on academic achievement through the mediating effects of autonomous motivation. In terms of the effect sizes, the findings showed that PoM explained about 1% to 18% of the variance in academic achievement and motivation. The theoretical and practical implications of the results are elucidated.

Family Decision-Making Style, Peer Group Affiliation and Prior Academic Achievement as Predictors of the Academic Achievement of African American Students

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Engerman, Kimarie

2006-01-01

A study analyzed family decision-making style, peer group affiliation, and academic achievement in 10th grade as predictors of academic achievement of African American students in 12th grade. Findings indicated that though peer groups were known to influence academic performance, affiliation with learning oriented peers in 10th grade did not…

Home Influences on the Academic Performance of Agricultural Science Students in Ikwuano Local Government Area of Abia State, Nigeria

Science.gov (United States)

Ndirika, Maryann C.; Njoku, U. J.

2012-01-01

This study was conducted to investigate the home influences on the academic performance of agricultural science secondary school students in Ikwuano Local Government Area of Abia State. The instrument used in data collection was a validated questionnaire structured on a two point rating scale. Simple random sampling technique was used to select…

Students' academic self-efficacy viz-a-viz their academic achievement

African Journals Online (AJOL)

Self-efficacy predicts academic achievement by influencing the effect of skills, previous experience, mental ability, or other self-beliefs on subsequent achievement. Students with high self-efficacy set challenging goals engage in more effective learning strategy use and persevere when encountered by difficult tasks.

A greater voice for academic health sciences libraries: the Association of Academic Health Sciences Libraries' vision.

Science.gov (United States)

Bunting, Alison

2003-04-01

The founders of the Association of Academic Health Sciences Libraries (AAHSL) envisioned the development of a professional organization that would provide a greater voice for academic health sciences libraries, facilitate cooperation and communication with the Association of American Medical Colleges, and create a forum for identifying problems and solutions that are common to academic health sciences libraries. This article focuses on the fulfillment of the "greater voice" vision by describing action and leadership by AAHSL and its members on issues that directly influenced the role of academic health sciences libraries. These include AAHSL's participation in the work that led to the publication of the landmark report, Academic Information in the Academic Health Sciences Center: Roles for the Library in Information Management; its contributions to the recommendations of the Physicians for the Twenty-first Century: The GPEP Report; and the joint publication with the Medical Library Association of Challenge to Action: Planning and Evaluation Guidelines for Academic Health Sciences Libraries.

Factors Influencing Academic Failure of University Students

Science.gov (United States)

Khan, Yousaf Ali; Ahamad, Zahoor; Kousar, Sadia

2013-01-01

There was a close link between education and development. Education played a vital role in human capital formation. Academic failure from university was a problem that had became a serious concern for higher education institutions. This study presented the result of a recent investigation at the University of Gujrat that attempted to identify the…

Governance and Academic Culture in Higher Education: Under the Influence of the SSCI Syndrome

Directory of Open Access Journals (Sweden)

Chuing Prudence Chou

2017-10-01

Full Text Available The trend towards neo-liberal policies which began in the 1980s has caused public finances around the world to be linked to market forces rather than state allocation. In consequence, the sharp reduction in public funding allotted to the education sector has affected both social values and educational quality. With the growing influence of globalization on higher education, many East Asian nations have enacted urgent university reforms designed to boost competitiveness of their domestic university systems. China’s Projects 211 and 985; South Korea’s BK21; Japan’s National University Corporation Plan; and Taiwan’s ‘Five Year- Fifty Billion Plan have all been initiated in response to the process of globalization and the demand for global talent in academia. Elsewhere, governments in the Arab Middle East, the Americas, Europe, East and Southeast Asia have all initiated new policies to enhance the global competitiveness and international visibility of their flagship universities, and many of these focus in an unprecedented away on journal publication as the major performance criterion for faculty reward. The increasing extent to which government policies worldwide favour measurements derived from publication indexes such as SCI/SSCI has led to strengthened managerial governance over academic culture and the academic profession itself. This paper argues that a phenomenon of ‘publish globally and perish locally’ has emerged, especially in the humanities and social sciences which are most vulnerable to ‘SSCI Syndrome’, and that this trend is detrimental to academic effectiveness and diversity.

Multifaceted Impact of Self-Efficacy Beliefs on Academic Functioning.

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Bandura, Albert; And Others

1996-01-01

Analyzed the psychosocial influences through which efficacy beliefs affect academic achievement. Found that parents' sense of academic efficacy and aspirations for their children, children's beliefs in their efficacy to regulate their own learning and academic attainments, children's perceived social efficacy and ability to manage peer pressure,…

Influence of music training on academic examination-induced stress in Thai adolescents.

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Laohawattanakun, Janejira; Chearskul, Supornpim; Dumrongphol, Hattaya; Jutapakdeegul, Nuanchan; Yensukjai, Juntima; Khumphan, Nipaporn; Niltiean, Songwit; Thangnipon, Wipawan

2011-01-10

Several pieces of evidence suggest that academic examinations fulfill the classical requirement of a psychological stressor. Academic examinations represent a stressful challenge to many students, but studies on examination-dependent corticosteroid response, a sensitive physiological indicator of a stress response, are inconsistent. In addition, several studies showed that music can decrease cortisol and adrenocorticotropic hormone (ACTH) levels, and other studies have found that music also may enhance a variety of cognitive functions, such as attention, learning, communication and memory. The present study investigated cortisol response in saliva of Thai adolescents taking academic examinations and analyzed the differences of the stress response between musician and control subjects. Also, we observed whether the academic examination-dependent corticosteroid response affected learning and memory in the test subjects, which comprised 30 musician and 30 control students, age ranging from 15 to 17 years. Mathematical examinations were used as the stressor. Pre- and post-academic examination saliva cortisol levels were measured including self-estimated stress levels. Results showed that the pre-academic examination saliva cortisol concentrations of the musician group are significantly lower than those of the control group, whereas there is no difference in the stress inventory scores. Interestingly, among students with grade point average (GPA) of >3.50, pre-academic examination cortisol levels are significantly lower in the musician compared with control group. This study suggests that under academic examination-induced stress condition, music training can reduce saliva cortisol level in Thai adolescents. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Women Physicians: Choosing a Career in Academic Medicine

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Borges, Nicole J.; Navarro, Anita M.; Grover, Amelia C.

2011-01-01

Purpose Despite recent efforts to understand the complex process of physician career development, the medical education community has a poor understanding of why, how, and when women physicians embark on a career in academic medicine. Method In 2010, the authors phone-interviewed women physicians in academic medicine regarding why, how, and when they chose an academic medicine career. Project investigators first individually and then collectively analyzed transcripts to identify themes in the data. Results Through analyzing the transcripts of the 53 interviews, the investigators identified five themes related to why women choose careers in academic medicine: fit, aspects of the academic health center environment, people, exposure, and clincial medicine. They identified five themes related to how women make the decision to enter academic medicine: change in specialty, dissatisfaction with former career, emotionality, parental influence, and decision-making styles. The authors also identified four themes regarding when women decide to enter academic medicine: as a practicing phyisican, fellow, resident, or medical student. Conclusions Choosing a career in academic medicine is greatly influenced by the environment in which one trains and by people—be they faculty, mentors, role models, or family. An interest in teaching is a primary reason women choose a career in academic medicine. Many women physicians entering acadmic medicine chose this after or during fellowship, which is when they became more aware of academic medicine as a possible career. For many women, choosing academic medicine was not necessarily an active, planned decision; rather it was serendipitous or circumstantial. PMID:22104052

Sports Involvement and Academic Achievement: A Study of Malaysian University Athletes

Science.gov (United States)

Chuan, Chun Cheng; Yusof, Aminuddin; Shah, Parilah Mohd

2013-01-01

Factors that influence the academic achievement of Malaysian university athletes were investigated using 156 field hockey players from several universities. The relationship between team subculture, parental influence, the learning environment, support systems, financial aid, training factors, academic assistance, socialization, and stress level…

ACADEMIC MISSION - FROM AUTOCRACY TO BUREAUCRACY

Directory of Open Access Journals (Sweden)

LIVIU NEAMŢU

2015-12-01

Full Text Available The mission is generic expression of reason for the existence of an organization. Organizational mission ensure continuity of existence beyond the objectives and targets of activities. It is the expression of an organization's responsibilities towards the environment in which it belongs. As the organization grows and its activities or environmental conditions change, managers adapt their strategies, but stated mission will remain valid for a period of time or unchanged throughout the life of the organization. All managerial elements of the organization are aligned with stated mission, starting from the organization structure, management behavior or specific business processes. The focus of the mission of an higher education institution on a need or several integrated needs, on customers who manifest this need and on how they can be met, that really means defining of its strategic domanin, as a sphere of influence of the organization in their environment. In this sphere of influence, three components integrate on three levels of the mission: to establish needs; identify the customer type to which an organization adress and key competencies that differentiate it from the rest competitors. To that context identifies four specific forms of academic institutions starting from their mission and strategic area: autocratic academic institutions, meritocrate academic institutions, democratic academic institutions, bureaucrats academic institutions.

Academic performance of school children with behavioural ...

African Journals Online (AJOL)

Introduction: Behavioural disorders can have a negative influence on the academic performance of school children. There are no similiar published is no known studies in Nigeria. Objective: To compare the academic performance of primary school children with behavioural disorders with that of their controls. Methods: A ...

Performance management and academic workload in higher ...

African Journals Online (AJOL)

The South African Higher Education system is in a state of rapid flux. Various factors are rendering education vulnerable to destructive influences. It has become imperative for academic managers to ensure that academic staff function productively. Management information systems which will generate correct information as ...

Relationship between Motivation and Academic Performance of ...

African Journals Online (AJOL)

The study investigated the influence of motivation on the academic performance of undergraduate distance learners of the University of Cape Coast, Ghana. The study was guided by two hypotheses; the relationship between intrinsic motivation and academic performance of Level 300 undergraduate students of College of ...

The Influence of Reciprocal interactions in the Family on Academic Performance among Secondary School Students in Kenya

OpenAIRE

Rael Achieng Ogwari; Dr. Catherine Simiyu; Professor Jonah Nyaga Kindiki

2014-01-01

This study aimed to investigate the influence of reciprocal interactions in the family on academic performance among secondary school students in Siaya District. Stratified and purposive sampling techniques were used to select the study participants. The sample comprised of a total of 243 students (154 boys and 89 girls) drawn from 27 public coeducational schools in the district.  Data was collected using student questionnaires. The researchers’ judgment of the representativeness of the items...

Flexible, Transparent, Thickness-Controllable SWCNT/PEDOT:PSS Hybrid Films Based on Coffee-Ring Lithography for Functional Noncontact Sensing Device

KAUST Repository

Tai, Yanlong

2015-12-08

Flexible transparent conductive films (FTCFs) as the essential components of the next generation of functional circuits and devices are presently attracting more attention. Here, a new strategy has been demonstrated to fabricate thickness-controllable FTCFs through coffee ring lithography (CRL) of single-wall carbon nanotube (SWCNT)/poly(3,4-ethylenedioxythiophene)-polystyrenesulfonate (PEDOT:PSS) hybrid ink. The influence of ink concentration and volume on the thickness and size of hybrid film has been investigated systematically. Results show that the final FTCFs present a high performance, including a homogeneous thickness of 60-65 nm, a sheet resistance of 1.8 kohm/sq, a visible/infrared-range transmittance (79%, PET = 90%), and a dynamic mechanical property (>1000 cycle, much better than ITO film), respectively, when SWCNT concentration is 0.2 mg/mL, ink volume is 0.4 μL, drying at room temperature. Moreover, the benefits of these kinds of FTCFs have been verified through a full transparent, flexible noncontact sensing panel (3 × 4 sensing pixels) and a flexible battery-free wireless sensor based on a humidity sensing mechanism, showing excellent human/machine interaction with high sensitivity, good stability, and fast response/recovery ability. © 2015 American Chemical Society.

Flexible, Transparent, Thickness-Controllable SWCNT/PEDOT:PSS Hybrid Films Based on Coffee-Ring Lithography for Functional Noncontact Sensing Device

KAUST Repository

Tai, Yanlong; Yang, Zhen Guo

2015-01-01

Flexible transparent conductive films (FTCFs) as the essential components of the next generation of functional circuits and devices are presently attracting more attention. Here, a new strategy has been demonstrated to fabricate thickness-controllable FTCFs through coffee ring lithography (CRL) of single-wall carbon nanotube (SWCNT)/poly(3,4-ethylenedioxythiophene)-polystyrenesulfonate (PEDOT:PSS) hybrid ink. The influence of ink concentration and volume on the thickness and size of hybrid film has been investigated systematically. Results show that the final FTCFs present a high performance, including a homogeneous thickness of 60-65 nm, a sheet resistance of 1.8 kohm/sq, a visible/infrared-range transmittance (79%, PET = 90%), and a dynamic mechanical property (>1000 cycle, much better than ITO film), respectively, when SWCNT concentration is 0.2 mg/mL, ink volume is 0.4 μL, drying at room temperature. Moreover, the benefits of these kinds of FTCFs have been verified through a full transparent, flexible noncontact sensing panel (3 × 4 sensing pixels) and a flexible battery-free wireless sensor based on a humidity sensing mechanism, showing excellent human/machine interaction with high sensitivity, good stability, and fast response/recovery ability. © 2015 American Chemical Society.

The Influence of Self-Compassion on Academic Procrastination and Dysfunctional Attitudes

Science.gov (United States)

Iskender, Murat

2011-01-01

In the present study, aims were (1) to determine gender differences in self-compassion, academic procrastination, and dysfunctional attitudes and (2) to examine the relationships between self-compassion, academic procrastination, and dysfunctional attitudes. Participants were 251 university students who completed a questionnaire package that…

Factors influencing academic library users' intention to use mobile systems:A comparison of current users and potential adopters

Institute of Scientific and Technical Information of China (English)

Haijuan YANG; Sisi GUI

2014-01-01

Purpose:The study intends to examine the factors influencing the behavioral intention to use academic libraries' mobile systems from the perspective of current users and potential adopters,respectively.Design/methodology/approach:Our study investigates the mobile library system's acceptance by using a context-specific extension of the theory of reasoned action (TRA) and the technology acceptance model (TAM),which includes such factors as mobile self-efficacy,personal innovativeness and perceived playfulness.Structural equation modeling was used to test the validity of the proposed model based on the empirical data which was collected from 210 questionnaire survey participants.Findings:The result shows that 1) for both current users and potential adopters,attitude toward use and subjective norm both have a significant and positive impact on behavioral intention to use;2) perceived usefulness and perceived ease of use are significantly correlated to potential adopters' attitude toward use whereas perceived usefulness and perceived playfulness are significantly related to current users' attitude toward use;3) as for the comparison between the two groups of users,personal innovativeness not only affects perceived usefulness of both current users and potential adopters,but also affects potential adopters' perceived playfulness positively.Mobile self-efficacy has a significant effect on perceived ease of use for both types of users.Research limitations:Although the sample size met the basic statistics requirements for the social research,the participants were mainly college students,and other mobile system users like faculty members and researchers were not investigated.In addition,some influencing factors,such as information quality,system quality and service quality were not considered in the research model.Practical implications:This study reveals main factors which influence both current users and potential adopters' intention to use the mobile system

Factors influencing academic library users’ intention to use mobile systems: A comparison of current users and potential adopters

Institute of Scientific and Technical Information of China (English)

Haijuan; YANG; Sisi; GUI

2014-01-01

Purpose: The study intends to examine the factors influencing the behavioral intention to use academic libraries’ mobile systems from the perspective of current users and potential adopters, respectively. Design/methodology/approach: Our study investigates the mobile library system’s acceptance by using a context-specific extension of the theory of reasoned action(TRA) and the technology acceptance model(TAM), which includes such factors as mobile self-efficacy, personal innovativeness and perceived playfulness. Structural equation modeling was used to test the validity of the proposed model based on the empirical data which was collected from 210 questionnaire survey participants.Findings: The result shows that 1) for both current users and potential adopters, attitude toward use and subjective norm both have a significant and positive impact on behavioral intention to use; 2) perceived usefulness and perceived ease of use are significantly correlated to potential adopters’ attitude toward use whereas perceived usefulness and perceived playfulness are significantly related to current users’ attitude toward use; 3) as for the comparison between the two groups of users, personal innovativeness not only affects perceived usefulness of both current users and potential adopters, but also affects potential adopters’ perceived playfulness positively. Mobile self-efficacy has a significant effect on perceived ease of use for both types of users.Research limitations: Although the sample size met the basic statistics requirements for the social research, the participants were mainly college students, and other mobile system users like faculty members and researchers were not investigated. In addition, some influencing factors, such as information quality, system quality and service quality were not considered in the research model.Practical implications: This study reveals main factors which influence both current users and potential adopters’ intention to use

Influence of anionic and cationic polyelectrolytes on the conductivity and morphology of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) films

Energy Technology Data Exchange (ETDEWEB)

Valtakari, Dimitar, E-mail: dimitar.valtakari@abo.fi [Abo Akademi University, Laboratory of Paper Coating and Converting, Center for Functional Materials at Biological Interfaces (FUNMAT), Porthansgatan 3, FI-20500 Åbo/Turku (Finland); Bollström, Roger [Omya International AG, CH 4665 Oftringen (Switzerland); Toivakka, Martti; Saarinen, Jarkko J. [Abo Akademi University, Laboratory of Paper Coating and Converting, Center for Functional Materials at Biological Interfaces (FUNMAT), Porthansgatan 3, FI-20500 Åbo/Turku (Finland)

2015-09-01

Conductivity of the poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) strongly depends on the film morphology, which can be altered by the presence of polyelectrolytes. Aqueous dispersion of PEDOT:PSS was studied with anionic sodium polyacrylate (PA) and cationic poly(dimethyldiallylammonium chloride) (pDADMAC) polyelectrolytes that are typically used in papermaking as retention aids and dispersing agents in the paper pigment coating formulations. Spin-coated PEDOT:PSS films on a PA coated glass formed non-uniform layers with lowered conductivity compared to the reference PEDOT:PSS films on a clean glass substrate. On contrary, spin-coated PEDOT:PSS on a pDADMAC coated glass formed uniform layers with good conductivity. These results point out the importance of surface chemistry when using renewable and recyclable paper-based substrates with the PEDOT:PSS films. - Highlights: • PEDOT:PSS polymer was studied in the presence of polyelectrolytes. • Uniform layers of PEDOT:PSS and polyelectrolytes were spin-coated on glass. • Cationic polyelectrolyte was found to be more susceptible to humidity. • Cationic polyelectrolyte improves the conductivity of PEDOT:PSS. • PEDOT:PSS forms non-uniform layers on anionic polyelectrolyte coated glass.

Influence of anionic and cationic polyelectrolytes on the conductivity and morphology of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) films

International Nuclear Information System (INIS)

Valtakari, Dimitar; Bollström, Roger; Toivakka, Martti; Saarinen, Jarkko J.

2015-01-01

Conductivity of the poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) strongly depends on the film morphology, which can be altered by the presence of polyelectrolytes. Aqueous dispersion of PEDOT:PSS was studied with anionic sodium polyacrylate (PA) and cationic poly(dimethyldiallylammonium chloride) (pDADMAC) polyelectrolytes that are typically used in papermaking as retention aids and dispersing agents in the paper pigment coating formulations. Spin-coated PEDOT:PSS films on a PA coated glass formed non-uniform layers with lowered conductivity compared to the reference PEDOT:PSS films on a clean glass substrate. On contrary, spin-coated PEDOT:PSS on a pDADMAC coated glass formed uniform layers with good conductivity. These results point out the importance of surface chemistry when using renewable and recyclable paper-based substrates with the PEDOT:PSS films. - Highlights: • PEDOT:PSS polymer was studied in the presence of polyelectrolytes. • Uniform layers of PEDOT:PSS and polyelectrolytes were spin-coated on glass. • Cationic polyelectrolyte was found to be more susceptible to humidity. • Cationic polyelectrolyte improves the conductivity of PEDOT:PSS. • PEDOT:PSS forms non-uniform layers on anionic polyelectrolyte coated glass

Job Satisfaction of Academics: Does Gender Matter?

Science.gov (United States)

Machado-Taylor, Maria de Lourdes; White, Kate; Gouveia, Odilia

2014-01-01

Academic work in higher education has been influenced by global trends such as accountability, massification and deteriorating financial support. Within this broader context, the performance of academic staff as teachers and researchers has an impact on student learning and implications for the quality of higher education institutions (HEIs).…

ADHD symptoms, academic achievement, self-perception of academic competence and future orientation: a longitudinal study.

Science.gov (United States)

Scholtens, Sara; Rydell, Ann-Margret; Yang-Wallentin, Fan

2013-06-01

In the investigation of the effect of attention deficit hyperactivity disorder (ADHD) symptoms on school careers there is a need to study the role of adolescent and childhood ADHD symptoms and academic achievement, and to incorporate measures that include the individual's perspective. Our aim was to gain an overview of the long-term development of school careers in relation to ADHD symptoms. We studied associations between ADHD symptoms and academic achievement at different time-points and future orientation at the end of high school, and assessed the role of self-perceptions of academic competence in these associations. Participants were 192 children (47% girls) with a range of ADHD symptoms taken from a community sample. Collecting data at three time points, in 6th, 11th and 12th grade we tested a structural equation model. Results showed that ADHD symptoms in 6th grade negatively affected academic achievement concurrently and longitudinally. ADHD symptoms in 11th grade negatively affected concurrent academic achievement and academic self-perception and future orientation in 12th grade. Academic achievement had a positive influence on academic self-perception and future orientation. Given the other factors, self-perception of academic competence did not contribute to outcomes. We concluded that early ADHD symptoms may cast long shadows on young people's academic progress. This happens mainly by way of stability in symptoms and relations to early low academic achievement. © 2013 The Authors. Scandinavian Journal of Psychology © 2013 The Scandinavian Psychological Associations.

How Does Ethics Institutionalization Reduce Academic Cheating?

Science.gov (United States)

Popoola, Ifeoluwa; Garner, Bart; Ammeter, Anthony; Krey, Nina; Beu Ammeter, Danielle; Schafer, Stuart

2017-01-01

Extant research on academic cheating primarily focuses on the impact of honor codes on academic cheating. However, the influence of ethics institutionalization is curiously missing in past research. The authors developed and validated a structural equations model in the R programming language to examine the impact of formal (explicit) and informal…

Influence of Weak Base Addition to Hole-Collecting Buffer Layers in Polymer:Fullerene Solar Cells

Directory of Open Access Journals (Sweden)

Jooyeok Seo

2017-02-01

Full Text Available We report the effect of weak base addition to acidic polymer hole-collecting layers in normal-type polymer:fullerene solar cells. Varying amounts of the weak base aniline (AN were added to solutions of poly(3,4-ethylenedioxythiophene:poly(styrenesulfonate (PEDOT:PSS. The acidity of the aniline-added PEDOT:PSS solutions gradually decreased from pH = 1.74 (AN = 0 mol% to pH = 4.24 (AN = 1.8 mol %. The electrical conductivity of the PEDOT:PSS-AN films did not change much with the pH value, while the ratio of conductivity between out-of-plane and in-plane directions was dependent on the pH of solutions. The highest power conversion efficiency (PCE was obtained at pH = 2.52, even though all devices with the PEDOT:PSS-AN layers exhibited better PCE than those with the pristine PEDOT:PSS layers. Atomic force microscopy investigation revealed that the size of PEDOT:PSS domains became smaller as the pH increased. The stability test for 100 h illumination under one sun condition disclosed that the PCE decay was relatively slower for the devices with the PEDOT:PSS-AN layers than for those with pristine PEDOT:PSS layers.

PSS Support for Maritime Technology Ventures: From Exploration to Methodology and Theory

DEFF Research Database (Denmark)

Andersen, Jakob Axel Bejbro

-efficient, competitive Eastern suppliers. The Danish suppliers - by some considered the world leaders in terms of technological knowledge - are faced with a difficult choice: Either try to survive by cutting costs and competing on price or attempt to leverage their unique knowledge of technology to the market and build...... new business ventures, which are not dependent on cost as a competitive factor. The recommendation of this thesis is to pursue the latter option and adopt entrepreneurial strategies as a means to future prosperity. To achieve this goal, the area of Product/Service-Systems (PSS) is introduced...... to validate an existing theory for entrepreneurship process against the data. This study fails to find proof for or against the assertions of the theory. In the last study, a grounded theory approach is used for building a conceptual framework for entrepreneurship processes. As such, the framework is entirely...

Social Networking and Academic Performance: A Review

Science.gov (United States)

Doleck, Tenzin; Lajoie, Susanne

2018-01-01

The ubiquitous use of social networking sites by students and the potential impacts of such use on academic performance are of both theoretical and practical importance. Hence, this paper addresses the question: how does the use of social networking sites influence academic performance? The present review synthesizes the empirical findings of the…

Relation between academic yield and stress in medical students

Directory of Open Access Journals (Sweden)

Sandra Patricia González Peña

2006-12-01

Full Text Available Objective. To study risk factors that where found as influence in the academic yield (stress, alcohol, friendships, depression and family relations in the students of the Medicine Faculty of the Universidad de Manizales. Materials and methods: Descriptive study integrated by random selected sample, who were attending of II to XI semester of the Medicine faculty. An anonymous survey was conduced about sociodemographic, cultural, academic and motivational characteristics,including stress, depresión, family disfunction and substance abuse. We correlated all variables with academic yield using chi square test, Pearson`s coefficient and lineal regression. Results: 212 students of ages between 17 and 31 years where analyzed, in which the majority where from another city. Some of the factors were detected which affect the academic yield of the students as it is stress, depression, the family function and friendships among others. Conclusions: A significant relation between academic yield and stress was found. In turn, stress variable was influenced by depression, alcohol and family relation.

A study of factors influencing surgical cesarean delivery times in an academic tertiary center.

Science.gov (United States)

Gonzalez Fiol, A; Meng, M-L; Danhakl, V; Kim, M; Miller, R; Smiley, R

2018-05-01

Knowledge of hospital-specific average cesarean delivery operative times, and factors influencing length of surgery, can serve as a guide for anesthesiologists when choosing the optimal anesthetic technique. The aim of this study was to determine operative times and the factors influencing those times for cesarean delivery. We conducted a retrospective review of all 1348 cesarean deliveries performed at an academic hospital in 2011. The primary outcome was mean operative time for first, second, third and fourth or more cesarean deliveries. The secondary goal was to identify factors influencing operative time. Variables included age, body mass index, previous surgery, gestational age, urgency of cesarean delivery, anesthesia type, surgeon's seniority, layers closed, and performance of tubal ligation. Mean (standard deviation) operative times for first (n=857), second (n=353), third (n=108) and fourth or more (n=30) cesarean deliveries were 56 (19), 60 (19), 69 (28) and 82 (31) minutes, respectively (P cesarean delivery or the presence of other factors that could increase operative time may warrant catheter-based anesthetic techniques or the addition of adjunctive medications to prolong spinal anesthetic block. Institutional and individual surgeon factors may play an even more important role in determining surgical time. Copyright © 2018 Elsevier Ltd. All rights reserved.

A Synthesis Model of Sustainable Market Orientation: Conceptualization, Measurement, and Influence on Academic Accreditation--A Case Study of Egyptian-Accredited Faculties

Science.gov (United States)

Abou-Warda, Sherein H.

2014-01-01

Higher education institutions are increasingly concerned about accreditation. Although sustainable market orientation (SMO) bears on academic accreditation, to date, no study has developed a valid scale of SMO or assessed its influence on accreditation. The purpose of this paper is to construct and validate an SMO scale that was developed in…

Influence of environmental health services on students' academic ...

African Journals Online (AJOL)

The study investigated the effect of environmental health services on students' academic performance in secondary schools in Brass Local Government Area of Bayelsa State. The study adopted the descriptive survey design. The sample for the study comprised a total of 245 students and 59 teachers, amounting to 304 ...

the influence of instructional materials on academic performance

African Journals Online (AJOL)

students' academic performance in senior secondary school Chemistry in Cross River State. ... the motivation on the teaching-learning process. ... Today advances in technology have ... retention. A truism often heard in teaching is that if you have not learnt, I have not taught. A .... resources have significant effect on students'.

Assessing the relationship between perceived emotional intelligence and academic performance of medical students

Science.gov (United States)

Rajasingam, Uma; Suat-Cheng, Peh; Aung, Thidar; Dipolog-Ubanan, Genevieve; Wei, Wee Kok

2014-12-01

This study examines the association between emotional intelligence and its influence on academic performance on medical students to see if emotional intelligence emerges as a significant influencer of academic achievement. The instrument used is the Trait-Meta Mood Scale (TMMS), a 30-item self-report questionnaire designed to measure an individual's perceived emotional intelligence (PEI). Participants are required to rate the extent to which they agree with each item on a 5-point Likert scale. The TMMS consists of three subscales - Attention to Feelings (which measures the extent to which individuals notice and think about their feelings, Clarity (which measures the extent to which an individual is able to discriminate among different moods) and Mood Repair (related to an individual's ability to repair/terminate negative moods or maintain pleasant ones). Of special interest is whether high scores in the Clarity and Repair subscales correlate positively with academic performance, and whether high scores on the Attention subscale, without correspondingly high scores in the Clarity and Mood Repair subscales, correlates negatively with academic performance. Sample population includes all medical students (Years 1-5) of the MD program in UCSI University, Malaysia. Preliminary analysis indicates no significant relationship between overall TMMS scores and academic performance; however, the Attention subscale is significantly correlated to academic performance. Therefore even though PEI has to be ruled out as an influencer on academic performance for this particular sample, the fact that Attention has a significant relationship with academic performance may give some insight into the factors that possibly influence medical students' academic performance.

Developing and Testing a Method to Measure Academic Societal Impact

Science.gov (United States)

Phillips, Paul; Moutinho, Luiz; Godinho, Pedro

2018-01-01

This paper aims to extend understanding of the business and societal impact of academic research. From a business school perspective, it has taken stock of the role of academic research and relevance in business and society. The proposed conceptual framework highlights the forces influencing the pursuit of academic rigour and relevance in…

Work-Life Conflict among Young Academics: Antecedents and Gender Effects

Science.gov (United States)

Dorenkamp, Isabelle; Süß, Stefan

2017-01-01

Aligning work and private life is a significant challenge for young academics because of demanding working conditions (e.g. high workload, low job security). It is particularly strong for young female academics due to growing family responsibilities. Our study aims to identify the factors influencing the work-life conflict of young academics and…

Evolution of design of PSS from NAPP to RAPP-3,4

International Nuclear Information System (INIS)

Dixit, K.B.; Kapoor, H.; Biswas, G.

1997-01-01

Primary Shut off System (PSS) is a fast acting system which shuts down the reactor from normal as well as accident conditions. Cadmium tube sandwiched between stainless steel 304L grade tubes is used as neutron absorbing element at fourteen locations on the reactor vessel. The elements are dropped there in the reactor with the help of drive mechanisms. This system was used for the first time in NAPS and was indigenously designed and manufactured. Based on experience in commissioning and operation, this has further been improved for subsequent projects at Kakrapar, Kaiga and RAPP-3 and 4. The improvement include change of rope drum to sheave type rope winding system, use of higher capacity indigenous specially designed electromagnetic clutch, use of higher dia wire rope, elimination of spiral springs, use of large size dash pot, reduction in number of components, incorporation of mechanical seals in place of O rings, modification of guide tube. With the above modifications the reliability of the system has been enhanced and chances of failure of components have been minimized due to higher factor of safety

Learning styles, academic achievement, and mental health problems among medical students in Thailand.

Science.gov (United States)

Paiboonsithiwong, Salilthip; Kunanitthaworn, Natchaya; Songtrijuck, Natchaphon; Wongpakaran, Nahathai; Wongpakaran, Tinakon

2016-01-01

This study aimed to investigate the prevalence of various learning styles among medical students and their correlations with academic achievement and mental health problems in these students. This study was conducted among 140 first-year medical students of Chiang Mai University, Thailand in 2014. The participants completed the visual-aural-read/write-kinesthetic (VARK) questionnaire, the results of which can be categorized into 4 modes, corresponding to how many of the 4 types are preferred by a respondent. The 10-item Perceived Stress Scale (PSS-10) and the 21-item Outcome Inventory (OI-21) were also used. The participants' demographic data, grade point average (GPA), and scores of all measurements are presented using simple statistics. Correlation and regression analysis were employed to analyze differences in the scores and to determine the associations among them. Sixty percent of the participants were female. The mean age was 18.86±0.74 years old. Quadmodal was found to be the most preferred VARK mode (43.6%). Unimodal, bimodal, and trimodal modes were preferred by 35%, 12.9%, and 18.6% of the participants, respectively. Among the strong unimodal learners, visual, aural, read/write, and kinesthetic preferences were reported by 4.3%, 7.1%, 11.4%, and 12.1% of participants, respectively. No difference was observed in the PSS-10, OI-anxiety, OI-depression, and OI-somatization scores according to the VARK modes, although a significant effect was found for OI-interpersonal (F=2.788, P=0.043). Moreover, neither VARK modes nor VARK types were correlated with GPA. The most preferred VARK learning style among medical students was quadmodal. Learning styles were not associated with GPA or mental health problems, except for interpersonal problems.

Learning styles, academic achievement, and mental health problems among medical students in Thailand

Directory of Open Access Journals (Sweden)

Salilthip Paiboonsithiwong

2016-10-01

Full Text Available Purpose This study aimed to investigate the prevalence of various learning styles among medical students and their correlations with academic achievement and mental health problems in these students. Methods This study was conducted among 140 first-year medical students of Chiang Mai University, Thailand in 2014. The participants completed the visual-aural-read/write-kinesthetic (VARK questionnaire, the results of which can be categorized into 4 modes, corresponding to how many of the 4 types are preferred by a respondent. The 10-item Perceived Stress Scale (PSS-10 and the 21-item Outcome Inventory (OI-21 were also used. The participants’ demographic data, grade point average (GPA, and scores of all measurements are presented using simple statistics. Correlation and regression analysis were employed to analyze differences in the scores and to determine the associations among them. Results Sixty percent of the participants were female. The mean age was 18.86±0.74 years old. Quadmodal was found to be the most preferred VARK mode (43.6%. Unimodal, bimodal, and trimodal modes were preferred by 35%, 12.9%, and 18.6% of the participants, respectively. Among the strong unimodal learners, visual, aural, read/write, and kinesthetic preferences were reported by 4.3%, 7.1%, 11.4%, and 12.1% of participants, respectively. No difference was observed in the PSS-10, OI-anxiety, OI-depression, and OI-somatization scores according to the VARK modes, although a significant effect was found for OI-interpersonal (F=2.788, P=0.043. Moreover, neither VARK modes nor VARK types were correlated with GPA. Conclusion The most preferred VARK learning style among medical students was quadmodal. Learning styles were not associated with GPA or mental health problems, except for interpersonal problems.

Students' Persistence and Academic Success in a First-Year Professional Bachelor Program: The Influence of Students' Learning Strategies and Academic Motivation

OpenAIRE

Vanthournout, Gert; Gijbels, David; Coertjens, Liesje; Donche, Vincent; Van Petegem, Peter

2012-01-01

The present study explores whether students' learning strategies and academic motivation predict persistence and academic success in the first year of higher education. Freshmen students in a professional bachelor program in teacher education were questioned on their learning strategy use and motivation at the start and at the end of the academic year. Students' learning strategies were assessed using the inventory of learning styles-SV. Motivation was measured using scales from the self-regu...

Influence of Public Relations and Reference Services on Academic ...

African Journals Online (AJOL)

... infrastructure. Keywords: Academic Library, library services, Public relations, Reference Services ... books and journal articles for writing them and doing class assignment. ..... the present economic situation in the country is having adverse ...

Sleep and Academic Performance in Hong Kong Adolescents

Science.gov (United States)

Mak, Kwok-Kei; Lee, So-Lun; Ho, Sai-Yin; Lo, Wing-Sze; Lam, Tai-Hing

2012-01-01

Background: Sleep problems may have different influences on students' academic performance. We investigated the prevalence of sleep patterns, naps, and sleep disorders, and their associations with academic performance in Hong Kong adolescents. Methods: In 2007-2008, 22,678 students aged 12-18 (41.6% boys) completed a questionnaire on…

From LCA to PSS – Making leaps towards sustainability by applying product/service-system thinking in product development

DEFF Research Database (Denmark)

Bey, Niki; McAloone, Timothy Charles

2006-01-01

for optimisations on all system levels. However, as the act of ecodesign conventionally focuses on physical products, the search for potential optimisations is usually directed ‘downwards’, i.e. towards lower system levels, resulting in optimised components within products rather than optimised products within...... their surrounding systems. This paper will exemplify that when broadening the ecodesign horizon to environmental product/service-system (PSS) design, there is a better possibility of applying a system-oriented life cycle thinking approach, and therefore a potential to yield extreme improvements towards...

Academic Performance and the Use of Social Networks

Directory of Open Access Journals (Sweden)

Jéssica Ribeiro Rangel

2016-08-01

Full Text Available This study aimed to investigate whether the use of social networks influences on the academic performance of students in the undergraduate program in accounting. Data were collected from 322 students of the course of a federal University of the State of Minas Gerais, Brazil. The regression results show that the variables "gender", "motivation" and "classification in the University entrance examination" are significant in explaining students' academic performance measured by the Grade Point Average (GPA. The results show that the performance of male students is lower than that of female students at the level of 5%. Also was identified that the greater the student's motivation level, the greater your academic performance (at the level of 1 percent. Finally, it was observed that the best ranked students in the University entrance examination, the higher their academic performance. However, none of the variables relating to the use of social networks ("familiarity with technological resources", "hours", "Internet hours on social networks" and "use of social networks to study" presented relation with academic performance. In other words, these results show that the use of social networks does not have positive or negative impacts directly on academic performance. We can conclude for the sample analyzed, that use of social networks during the academic period does not influence significantly the performance of the students. However, you can verify that the motivation is directly related to the academic performance of the Accounting student with regard to perception of motivation, to familiarity with technological resources and the use of applications.

Two Are Better than One: The Joint Influence of Maternal Preparedness for Parenting and Children's Self-Esteem on Academic Achievement and Adjustment

Science.gov (United States)

Farris, Jaelyn; Burke Lefever, Jennifer E.; Borkowski, John G.; Whitman, Thomas L.

2013-01-01

Research Findings: This study investigated the joint influence of maternal cognitive readiness to parent and children's self-esteem on children's academic achievement and behavioral adjustment in the classroom at age 10. Participants were 153 adolescent mothers and their firstborn children. Findings indicated that low levels of prenatal maternal…

Academic Administrator Influence on Institutional Commitment to Open Access of Scholarly Research

Science.gov (United States)

Reinsfelder, Thomas L.

2012-01-01

This quantitative study investigated the interrelationships among faculty researchers, publishers, librarians, and academic administrators when dealing with the open access of scholarly research. This study sought to identify the nature of any relationship between the perceived attitudes and actions of academic administrators and an…

Determinants of academic performance in children with sickle cell anaemia.

Science.gov (United States)

Ezenwosu, Osita U; Emodi, Ifeoma J; Ikefuna, Anthony N; Chukwu, Barth F; Osuorah, Chidiebere D

2013-11-19

Some factors are known to influence the academic performance of children with Sickle Cell Anaemia (SCA). Information on their effects in these children is limited in Nigeria. The factors which influence academic performance of children with SCA in Enugu, Nigeria are determined in this study. Consecutive children with SCA aged 5-11 years were recruited at the weekly sickle cell clinic of the University of Nigeria Teaching Hospital (UNTH) Enugu, Nigeria. Their age- and sex- matched normal classmates were recruited as controls. The total number of days of school absence for 2009/2010 academic session was obtained for each pair of pupils from the class attendance register. Academic performance was assessed using the average of the overall scores in the three term examinations of same session. Intelligence ability was determined with Draw-A-Person Quotient (DAPQ) using the Draw-A-Person Test while socio-economic status was determined using the occupational status and educational attainment of each parent. Academic performance of children with SCA showed statistically significant association with their socio-economic status (χ2 = 9.626, p = 0.047), and significant correlation with DAPQ (r = 0.394, p = 0.000) and age (r = -0.412, p = 0.000). However, no significant relationship existed between academic performance and school absence in children with SCA (r = -0.080, p = 0.453). Academic performance of children with SCA is influenced by their intelligence ability, age and socio-economic status but not negatively affected by their increased school absenteeism.

Parent-adolescent interaction: influence on the academic achievement of African American adolescent males.

Science.gov (United States)

Shearin, Sherin A

2002-01-01

As the achievement gap between African American and while students persists, an examination of factors outside the school setting are essential. Acknowledging the dynamics of family environment as perceived by African American adolescent males is apposite to understanding the relationship between family environment and academic achievement. Utilizing an ecological perspective, this study describes the characteristics of family process variables and analyzes the adolescents' perception of parent-adolescent interaction and its influence on their psychological well-being. Results indicate that a substantial proportion of the 179 adolescent males who perceived parent-adolescent interaction as positive and were identified as having a stable psychological well-being, were more likely to have average to above-average grade point averages, high Stanford Nine scores and high achievement group membership, than those adolescent males who did not perceive parent-adolescent interaction as positive.

Relationships between Learning Approach, Procrastination and Academic Achievement amongst First-Year University Students

Science.gov (United States)

Saele, Rannveig Grøm; Dahl, Tove Irene; Sørlie, Tore; Friborg, Oddgeir

2017-01-01

Individual differences in student learning influence academic performance, and two aspects influencing the learning process are the particular learning approach the students use and procrastination behaviour. We examined the relationships between learning approaches, procrastination and academic achievement (measured 1 year later as the grade…

Stress among UK Academics: Identifying Who Copes Best

Science.gov (United States)

Darabi, Mitra; Macaskill, Ann; Reidy, Lisa

2017-01-01

This article examined levels of stress and associated coping strategies among UK academics. Adopting a positive psychology approach, the influence of the character strengths of hope, optimism, gratitude and self-efficacy on stress, subjective well-being (SWB), and mental health was examined in 216 academics in a UK university. The study explored…

The influence of parenting style on academic achievement and career path

OpenAIRE

ZAHRA ZAHED ZAHEDANI; RITA REZAEE; ZAHRA YAZDANI; SINA BAGHERI; PARISA NABEIEI

2016-01-01

Introduction Several factors affect the academic performance of college students and parenting style is one significant factor. The current study has been done with the purpose of investigating the relationship between parenting styles, academic achievement and career path of students at Shiraz University of Medical Sciences.???? Methods This is a correlation study carried out at Shiraz University of Medical Sciences. Among 1600 students, 310 students were selected randomly as the sample. Bau...

Socialization of Perceived Academic Competence among Highly Competent Children.

Science.gov (United States)

Phillips, Deborah A.

1987-01-01

Academically competent third-graders and their parents were studied to (1) determine whether the illusion of incompetence documented in fifth graders appears in younger children; and (2) examine the influence that parents exert on their children's development of self-perceptions of academic competence. (PCB)

Social Network Perspectives Reveal Strength of Academic Developers as Weak Ties

Science.gov (United States)

Matthews, Kelly E.; Crampton, Andrea; Hill, Matthew; Johnson, Elizabeth D.; Sharma, Manjula D.; Varsavsky, Cristina

2015-01-01

Social network perspectives acknowledge the influence of disciplinary cultures on academics' teaching beliefs and practices with implications for academic developers. The contribution of academic developers in 18 scholarship of teaching and learning (SoTL) projects situated in the sciences are explored by drawing on data from a two-year national…

Change of Academic Major: The Influence of Broad and Narrow Personality Traits

Science.gov (United States)

Foster, N. A.

2017-01-01

The relationship between academic major change and ten personality traits (the Big Five and five narrow traits), was investigated in a sample of 437 college undergraduates. Contrary to expectations, Career Decidedness and Optimism were positively related to academic major change, regardless of class ranking. When parsing data by college year,…

Relative Age Effect and Academic Timing in American Junior College Baseball.

Science.gov (United States)

Beals, Thomas C; Furtado, Ovande; Fontana, Fabio E

2018-02-01

Previous research has shown that older athletes within age groupings are often perceived to be more talented simply due to advanced maturity, leading to biased selection in higher levels of sports competition, now commonly termed relative age effect (RAE). This study's goals were to determine whether (a) RAE influenced the selection of junior college baseball participants and (b) academic timing ( Glamser & Marciani, 1992 ), in which academic status determines age groupings more than strict age guidelines for college sports, influenced the formation of RAE. Participants were 150 junior college baseball players. Our results showed that RAE was only a significant factor, comparing the birth distribution of participants born before and after the midpoint of the participation year, when academic timing was also a factor in determining age groupings. In addition, the birth rate distribution, though not significantly different than expected, was greater only when those participants born during the expected participation year were included. The results of this study indicate that RAE could bear more influence among American student-athletes than was previously reported in that RAE in conjunction with academic timing does influence the selection of collegiate athletes.

Female and Male Psychologists in Academic Administration: Resource Control and Perceived Influence

Science.gov (United States)

Schenk, Jennifer

2010-01-01

This study examined male and female psychologists in academic administrative positions with regard to their perceptions of their own power and their actual power within the administrative hierarchies in which they work. In the past, researchers have compared women and men in academic administrative positions with regard to parity of numbers,…

The Influence of Self-Esteem and Selected Demographic Characteristics on First Semester Academic Achievement of Students Enrolled in a College of Agriculture

Science.gov (United States)

Gaspard, Mae B.; Burnett, Michael F.; Gaspard, Camile P.

2011-01-01

The primary purpose of this study was to determine the influence of self-esteem and selected demographic characteristics on academic achievement among students at the freshman level in the College of Agriculture at Louisiana State University. The sample of the study was all students at Louisiana State University enrolled in the Introduction to…

Career choice in academic medicine: systematic review.

Science.gov (United States)

Straus, Sharon E; Straus, Christine; Tzanetos, Katina

2006-12-01

To review systematically the evidence about what factors influence the decision to choose or not choose a career in academic medicine. A systematic review of relevant literature from 1990 to May 2005. Searches of The Cochrane Library, Medline (using Ovid and PubMed) from 1990 to May 2005, and EMBASE from 1990 to May 2005 were completed to identify relevant studies that explored the influential factors. Additional articles were identified from searching the bibliographies of retrieved articles. We attempted to identify studies that included residents, fellows, or staff physicians. No restrictions were placed on the study methodologies identified and all articles presenting empirical evidence were retrieved. For cohort, case-control, and cross-sectional studies, minimum inclusion criteria were the presence of defined groups, and the ability to extract relevant data. For surveys that involved case series, minimum inclusion criteria were a description of the population, and the availability of extractable data. Minimum inclusion criteria for qualitative studies were descriptions of the sampling strategy and methods. The search identified 251 abstracts; 25 articles were included in this review. Completion of an MD with a graduate degree or fellowship program is associated with a career in academic medicine. Of the articles identified in this review, this finding is supported by the highest quality of evidence. Similarly, the completion of research and publication of this research in medical school and residency are associated with a career in academic medicine. The desire to teach, conduct research, and the intellectual stimulation and challenge provided in academia may also persuade people to choose this career path. The influence of a role model or a mentor was reported by physicians to impact their decision making. Trainees' interest in academic medicine wanes as they progress through their residency. In order to revitalize academic medicine, we must engage trainees

Encouraging an environment to nurture lifelong learning: an Asian experience.

Science.gov (United States)

Jacobs, Joshua L; Samarasekera, Dujeepa D; Shen, Liang; Rajendran, K; Hooi, Shing Chuan

2014-02-01

Within an Asian context, this study examines the effect of changing from traditional course grades to a distinction/pass/fail (D/P/F) grading system on medical student self-perceived stress levels and on student exam performance. At the end of the 2010-2011 academic year, the Perceived Stress Scale-10 (PSS-10) was administered to the cohort of students finishing their first year of medical studies. For the academic year 2011-2012, the grading system was changed to D/P/F for the first year of medical school. The PSS-10 was also administered to the subsequent cohort of first-year medical students at the same point in the academic year as previous. Qualitative comments were collected for both cohorts. Stress as measured by the PSS-10 was significantly lower in the cohort that went through the year with the D/P/F grading system in place. Thematic analysis of qualitative responses showed a shift in sources of student stress away from peer-competition. There were no significant differences in overall exam performance. Within an Asian context, switching to a D/P/F grading system can alleviate stress and peer competition without compromising knowledge. This may help foster a "learning orientation" rather than an "exam orientation," and contribute to inculcating lifelong learning skills.

Retention of Mohs surgeons in academic dermatology.

Science.gov (United States)

Zhang, Shali; Mina, Mary Alice; Brown, Marc D; Zwald, Fiona O

2015-08-01

Retention of academic Mohs surgeons is important for the growth of this specialty and teaching of residents and students. To examine factors that influence retention of Mohs surgeons in academics and to better understand reasons for their departure. A survey was electronically distributed to academic Mohs surgeons in the American College of Mohs Surgery, asking them to rate the importance of several variables on their decision to remain in academia. Private practice Mohs surgeons who had left academics were also surveyed. Two hundred thirty-six dermatologic surgeons completed the survey. Twenty-nine percent work full time in academics, and approximately 7% work part time. The top reasons for practicing in the academic setting are intellectual stimulation, teaching opportunities, and collaboration with other university physicians and researchers. Seventy-one percent of respondents reported they would stay in academics, 7% indicated they would not, and 22% were unsure. Unfair compensation, inadequate support staff, poor leadership, increased bureaucracy, and decreased autonomy were top reasons that may compel a Mohs surgeon to leave. Opportunities for intellectual stimulation, collaboration, and teaching remain the main draw for academic Mohs surgeons. A supportive environment, strong leadership, and establishing fair compensation are imperative in ensuring their stay.

teachers' competence and students' academic performance

African Journals Online (AJOL)

This study investigated the influence of teacher's competence on students; academic ... Recommendations were made on how to promote further development of science teachers in Nigeria. ... physical sciences like chemistry, engineering and.

Robust Coordinated Design of PSS and TCSC using PSO Technique for Power System Stability Enhancement

Directory of Open Access Journals (Sweden)

S. Panda

2007-06-01

Full Text Available Power system stability improvement by coordinated design of a Power System Stabilizer (PSS and a Thyristor Controlled Series Compensator (TCSC controller is addressed in this paper. Particle Swarm Optimization (PSO technique is employed for optimization of the parameterconstrained nonlinear optimization problem implemented in a simulation environment. The proposed controllers are tested on a weakly connected power system. The non-linear simulation results are presented for wide range of loading conditions with various fault disturbances and fault clearing sequences as well as for various small disturbances. The eigenvalue analysis and simulation results show the effectiveness and robustness of proposed controllers to improve the stability performance of power system by efficient damping of low frequency oscillations under various disturbances.

Binary Logistic Regression Analysis in Assessment and Identifying Factors That Influence Students' Academic Achievement: The Case of College of Natural and Computational Science, Wolaita Sodo University, Ethiopia

Science.gov (United States)

Zewude, Bereket Tessema; Ashine, Kidus Meskele

2016-01-01

An attempt has been made to assess and identify the major variables that influence student academic achievement at college of natural and computational science of Wolaita Sodo University in Ethiopia. Study time, peer influence, securing first choice of department, arranging study time outside class, amount of money received from family, good life…

Response to Haskell's "Academic Freedom ... & Student Evaluation"

Directory of Open Access Journals (Sweden)

Jeffrey E. Stake

1997-03-01

Full Text Available Haskell (1997 argued that the administrative practice of student evaluation of faculty is a threat to academic freedom. However, before that claim can be substantiated, several prior questions must be addressed: To whom does academic freedom belong? Individual faculty? The academy? Whose actions can violate the right? Can any lines be drawn based on whether the substance or form of classroom behavior is influenced? And still another crucial point is whether a body can violate academic freedom without any intent to interfere with or control the substance of what is said to students.

Academic performance and behavioral patterns

DEFF Research Database (Denmark)

Kassarnig, Valentin; Mones, Enys; Bjerre-Nielsen, Andreas

2018-01-01

Identifying the factors that influence academic performance is an essential part of educational research. Previous studies have documented the importance of personality traits, class attendance, and social network structure. Because most of these analyses were based on a single behavioral aspect...

Study habit skills as correlate of academic performance of ...

African Journals Online (AJOL)

Study habit is one of the major factors that could influence students' academic attainment. Thus, this study examined study habit skills as correlate of academic performance of undergraduates in Edo state, Nigeria. It employed a correlation research design, using multistage sampling technique. Two hundred and forty eight ...

Effect of a PEDOT:PSS modified layer on the electrical characteristics of flexible memristive devices based on graphene oxide:polyvinylpyrrolidone nanocomposites

Science.gov (United States)

Kim, Woo Kyum; Wu, Chaoxing; Kim, Tae Whan

2018-06-01

The electrical characteristics of flexible memristive devices utilizing a graphene oxide (GO):polyvinylpyrrolidone (PVP) nanocomposite charge-trapping layer with a poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)-modified layer fabricated on an indium-tin-oxide (ITO)-coated polyethylene glycol naphthalate (PEN) substrate were investigated. Current-voltage (I-V) curves for the Al/GO:PVP/PEDOT:PSS/ITO/PEN devices showed remarkable hysteresis behaviors before and after bending. The maximum memory margins of the devices before and after 100 bending cycles were approximately 7.69 × 103 and 5.16 × 102, respectively. The devices showed nonvolatile memory effect with a retention time of more than 1 × 104 s. The "Reset" voltages were distributed between 2.3 and 3.5 V, and the "Set" voltages were dispersed between -0.7 and -0.2 V, indicative of excellent, uniform electrical performance. The endurance number of ON/OFF-switching and bending cycles for the devices was 1 × 102, respectively. The bipolar resistive switching behavior was explained on the basis of I-V results. In particular, the bipolar resistive switching behaviors of the LRS and the HRS for the devices are dominated by the Ohmic and space charge current mechanisms, respectively.

Influence of social cognitive and ethnic variables on academic goals of underrepresented students in science and engineering: a multiple-groups analysis.

Science.gov (United States)

Byars-Winston, Angela; Estrada, Yannine; Howard, Christina; Davis, Dalelia; Zalapa, Juan

2010-04-01

This study investigated the academic interests and goals of 223 African American, Latino/a, Southeast Asian, and Native American undergraduate students in two groups: biological science and engineering (S/E) majors. Using social cognitive career theory (Lent, Brown, & Hackett, 1994), we examined the relationships of social cognitive variables (math/science academic self-efficacy, math/science outcome expectations), along with the influence of ethnic variables (ethnic identity, other-group orientation) and perceptions of campus climate to their math/science interests and goal commitment to earn an S/E degree. Path analysis revealed that the hypothesized model provided good overall fit to the data, revealing significant relationships from outcome expectations to interests and to goals. Paths from academic self-efficacy to S/E goals and from interests to S/E goals varied for students in engineering and biological science. For both groups, other-group orientation was positively related to self-efficacy and support was found for an efficacy-mediated relationship between perceived campus climate and goals. Theoretical and practical implications of the study's findings are considered as well as future research directions.

Interpolymer complexation: comparisons of bulk and interfacial structures.

Science.gov (United States)

Cattoz, Beatrice; de Vos, Wiebe M; Cosgrove, Terence; Crossman, Martin; Espidel, Youssef; Prescott, Stuart W

2015-04-14

The interactions between the strong polyelectrolyte sodium poly(styrenesulfonate), NaPSS, and the neutral polymer poly(vinylpyrrolidone), PVP, were investigated in bulk and at the silica/solution interface using a combination of diffusion nuclear magnetic resonance spectroscopy (NMR), small-angle neutron scattering (SANS), solvent relaxation NMR, and ellipsometry. We show for the first time that complex formation occurs between NaPSS and PVP in solution; the complexes formed were shown not to be influenced by pH variation, whereas increasing the ionic strength increases the complexation of NaPSS but does not influence the PVP directly. The complexes formed contained a large proportion of NaPSS. Study of these interactions at the silica interface demonstrated that complexes also form at the nanoparticle interface where PVP is added in the system prior to NaPSS. For a constant PVP concentration and varying NaPSS concentration, the system remains stable until NaPSS is added in excess, which leads to depletion flocculation. Surface complex formation using the layer-by-layer technique was also reported at a planar silica interface.

Academic and Socio-demographic Causes of Medical Student's underachievement in Iranian Medical Schools: A Systematic Review

OpenAIRE

Keivan Dolati; Hosein Hamadiyan; Fazilat Pour Ashouri; Sepehr Rasekhi

2016-01-01

The academic performance of medical students seems to influence and be influenced by various factors. Identification of the factors that would influence the academic performance may help to modify some of these factors which may be reflecting positively on student’s GPA. Therefore, the objective of present study was to examine the effects of factors such as the student’s demographic data, educational and socio-cultural factors on the academic underachievement of Iranian medical students. In t...

The Danish Prostatic Symptom Score (DAN-PSS-1) questionnaire is reliable in stroke patients

DEFF Research Database (Denmark)

Tibaek, Sigrid; Jensen, Rigmor; Klarskov, Peter

2006-01-01

. The questionnaire consists of 12 questions related to lower urinary tract symptoms (LUTS). The participants were asked to state the frequency and severity of their symptoms (symptom score) and its impact on their daily life (bother score). Seventy-one stroke patients were included and 59 (83%) answered...... the questionnaire twice. The reliability test was done in two aspects: (a) detecting the frequency of each symptom and its bother factor, the scores were reduced to a two-category scale (=0, >0) and simple kappa statistics was used; (b) detecting the severity of each symptom and its bother factor, the total scale...... (kappa(w) = 0.48) to good (kappa(w) = 0.68). CONCLUSIONS: The DAN-PSS-1 questionnaire had acceptable test-retest reliability and may be suitable for measuring the frequency and severity of LUTS and its bother factor in stroke patients....

Women in academic general surgery.

Science.gov (United States)

Schroen, Anneke T; Brownstein, Michelle R; Sheldon, George F

2004-04-01

To portray the professional experiences of men and women in academic general surgery with specific attention to factors associated with differing academic productivity and with leaving academia. A 131-question survey was mailed to all female (1,076) and a random 2:1 sample of male (2,152) members of the American College of Surgeons in three mailings between September 1998 and March 1999. Detailed questions regarding academic rank, career aspirations, publication rate, grant funding, workload, harassment, income, marriage and parenthood were asked. A five-point Likert scale measured influences on career satisfaction. Responses from strictly academic and tenure-track surgeons were analyzed and interpreted by gender, age, and rank. Overall, 317 surgeons in academic practice (168 men, 149 women) responded, of which 150 were in tenure-track positions (86 men, 64 women). Men and women differed in academic rank, tenure status, career aspirations, and income. Women surgeons had published a median of ten articles compared with 25 articles for men (p career satisfaction was high, but women reported feeling career advancement opportunities were not equally available to them as to their male colleagues and feeling isolation from surgical peers. Ten percent to 20% of surgeons considered leaving academia, with women assistant professors (29%) contemplating this most commonly. Addressing the differences between men and women academic general surgeons is critical in fostering career development and in recruiting competitive candidates of both sexes to general surgery.

Academic achievement in children with epilepsy: a review.

Science.gov (United States)

Reilly, Colin; Neville, Brian G R

2011-11-01

To examine published studies which have focussed on academic achievement in children with epilepsy with respect to prevalence rates of academic difficulties and possible correlates of academic achievement. This review examines studies which have focussed on prevalence rates of academic difficulties and correlates of academic achievement in children with epilepsy from 1990 to 2010. Prevalence rates of low academic achievement and academic underachievement are reported and correlates of academic achievement including seizure/epilepsy variables, demographic variables, and child/family variables are examined with respect to published studies. Published studies suggest that low academic achievement is more common than academic underachievement (achievement below that expected on basis of IQ scores) and it is not clear from published studies if rates of academic underachievement are significantly higher than in the general population. Clear patterns with regard to the identification of correlates of academic underachievement have not emerged although low achievement may be influenced in many cases by lower than average levels of cognitive functioning. Most studies have not focussed on the IQ-achievement discrepancy definitions of (specific) learning disability. Children with epilepsy who are experiencing academic difficulties may not qualify for formal educational supports to address these difficulties if eligibility criteria for such supports stress an IQ-achievement discrepancy. Copyright © 2011 Elsevier B.V. All rights reserved.

Are competition and extrinsic motivation reliable predictors of academic cheating?

Directory of Open Access Journals (Sweden)

Gábor eOrosz

2013-02-01

Full Text Available Previous studies suggest that extrinsic motivation and competition are reliable predictors of academic cheating. The aim of the present questionnaire study was to separate the effects of motivation- and competition-related variables on academic cheating by Hungarian high school students (N = 620, M = 264, F = 356. Structural equation modeling showed that intrinsic motivation has a negative effect, and amotivation has a positive indirect effect on self-reported academic cheating. In contrast, extrinsic motivation had no significant effect. Indirect positive influence on cheating, based on some characteristics of hypercompetition, was also found, whereas attitudes towards self-developmental competition had a mediated negative influence. Neither constructive nor destructive competitive classroom climate had a significant impact on academic dishonesty. Acceptance of cheating and guilt has significant and direct effect on self-reported cheating. In comparison with them, the effects of motivational and competition-related variables are relatively small, even negligible. These results suggest that extrinsic motivation and competition are not amongst the most reliable predictors of academic cheating behavior.

Are competition and extrinsic motivation reliable predictors of academic cheating?

Science.gov (United States)

Orosz, Gábor; Farkas, Dávid; Roland-Lévy, Christine

2013-01-01

Previous studies suggest that extrinsic motivation and competition are reliable predictors of academic cheating. The aim of the present questionnaire study was to separate the effects of motivation- and competition-related variables on academic cheating by Hungarian high school students (N = 620, M = 264, F = 356). Structural equation modeling showed that intrinsic motivation has a negative effect, and amotivation has a positive indirect effect on self-reported academic cheating. In contrast, extrinsic motivation had no significant effect. Indirect positive influence on cheating, based on some characteristics of hypercompetition, was also found, whereas attitudes toward self-developmental competition had a mediated negative influence. Neither constructive nor destructive competitive classroom climate had a significant impact on academic dishonesty. Acceptance of cheating and guilt has significant and direct effect on self-reported cheating. In comparison with them, the effects of motivational and competition-related variables are relatively small, even negligible. These results suggest that extrinsic motivation and competition are not amongst the most reliable predictors of academic cheating behavior.

How Do Interaction Experiences Influence Doctoral Students’ Academic Pursuits in Biomedical Research?

Science.gov (United States)

Kong, Xiaoqing; Chakraverty, Devasmita; Jeffe, Donna B.; Andriole, Dorothy A.; Wathington, Heather D.; Tai, Robert H.

2014-01-01

This exploratory qualitative study investigated how doctoral students reported their personal and professional interaction experiences that they believed might facilitate or impede their academic pursuits in biomedical research. We collected 19 in-depth interviews with doctoral students in biomedical research from eight universities, and we based our qualitative analytic approach on the work of Miles and Huberman. The results indicated that among different sources and types of interaction, academic and emotional interactions from family and teachers in various stages essentially affected students’ persistence in the biomedical science field. In addition, co-mentorship among peers, departmental environment, and volunteer experiences were other essential factors. This study also found related experiences among women and underrepresented minority students that were important to their academic pursuit. PMID:26166928

How Do Interaction Experiences Influence Doctoral Students' Academic Pursuits in Biomedical Research?

Science.gov (United States)

Kong, Xiaoqing; Chakraverty, Devasmita; Jeffe, Donna B; Andriole, Dorothy A; Wathington, Heather D; Tai, Robert H

2013-01-01

This exploratory qualitative study investigated how doctoral students reported their personal and professional interaction experiences that they believed might facilitate or impede their academic pursuits in biomedical research. We collected 19 in-depth interviews with doctoral students in biomedical research from eight universities, and we based our qualitative analytic approach on the work of Miles and Huberman. The results indicated that among different sources and types of interaction, academic and emotional interactions from family and teachers in various stages essentially affected students' persistence in the biomedical science field. In addition, co-mentorship among peers, departmental environment, and volunteer experiences were other essential factors. This study also found related experiences among women and underrepresented minority students that were important to their academic pursuit.

Development of the Diamond light source PSS in conformance with EN 61508

International Nuclear Information System (INIS)

Wilson, M.C.; Price, A.G.

2012-01-01

Diamond Light Source is constructing a third phase (Phase III) of photon beamlines and experiment stations. Experience gained in the design, realization and operation of the Personnel Safety Systems (PSS) on the first two phases of beamlines is being used to improve the design process for this development. Information on the safety functionality of Phase I and Phase II photon beamlines is maintained in a hazard database. The database is built using Microsoft Access 2007, it consists of table hazards, safeguards, frequencies of opportunity and outcome severities. Reports can be generated to support the EN 61508 process. These reports are used to assist in the design, verification and validation of the new PSSs. The data is used to make comparisons between beamlines, to validate safety functions and to record documentation for each beamline. The ability of the database to produce reports sorted and filtered on different criteria allows the production of reports tailored for specific stages of the EN 61508 process. The database is a useful tool but should not be employed blindly

Comparison of Long-Term Clinical Outcomes of Lesions Exhibiting Focal and Segmental Peri-Stent Contrast Staining.

Science.gov (United States)

Tokuda, Takahiro; Yamawaki, Masahiro; Takahara, Mitsuyohi; Mori, Shinsuke; Makino, Kenji; Honda, Yosuke; Takafuji, Hiroya; Takama, Takuro; Tsutsumi, Masakazu; Sakamoto, Yasunari; Takimura, Hideyuki; Kobayashi, Norihiro; Araki, Motoharu; Hirano, Keisuke; Ito, Yoshiaki

2016-03-18

Peri-stent contrast staining (PSS) after metallic drug-eluting stent deployment is associated with target lesion revascularization and very late stent thrombosis. However, the type of PSS that influences the clinical outcomes is unknown. Therefore, we aimed to reveal which PSS type was influencing clinical outcomes. This study included 5580 de novo lesions of 4405 patients who were implanted with a first- or second-generation drug-eluting stent and who were evaluated using follow-up angiography within 12 months after stent implantation. We compared the clinical outcomes of patients divided into focal PSS and segmental PSS groups for 6 years after stent implantation. Total PSS was observed in 97 lesions (2.2%), of which 42 and 55 lesions were focal and segmental PSS, respectively. Baseline characteristics were similar between groups, except for intraoperative chronic total occlusion (segmental PSS=47.3% versus focal PSS=11.9%, P=0.0001). The incidence of segmental PSS tended to be higher in patients with a first-generation drug-eluting stent (83.6% versus 16.4%, P=0.05). The cumulative incidence of stent thrombosis in the 6 years of segmental PSS group was significantly higher than that of the focal PSS group (13.9% versus 0%, P=0.04). The cumulative incidence of overall target lesion revascularization for restenosis, excluding target lesion revascularization procedures for stent thrombosis, was significantly higher in the segmental PSS group (38.0% versus 0%, P=0.01). The incidence of segmental PSS tended to be higher in patients with a first-generation drug-eluting stent and appeared to be significantly associated with target lesion revascularization and stent thrombosis. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

An Action Research Study on the Influence of Gangsta Rap on Academic and Behavioral Issues of 5th Grade African-American Males

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Lewis, Shaun; Boes, Susan R.; Chibbaro, Julie S.

2015-01-01

This small action research study (ARS) began with a review of the literature examining the relationship of gangsta rap in regards to academic achievement, self-esteem, decision-making, identity issues and development of young African American males. The purpose of the ARS was to examine the correlation between gangsta rap and its influence on 5th…

Motivation and academic achievement in medical students.

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Yousefy, Alireza; Ghassemi, Gholamreza; Firouznia, Samaneh

2012-01-01

Despite their ascribed intellectual ability and achieved academic pursuits, medical students' academic achievement is influenced by motivation. This study is an endeavor to examine the role of motivation in the academic achievement of medical students. In this cross-sectional correlational study, out of the total 422 medical students, from 4th to final year during the academic year 2007-2008, at School of Medicine, Isfahan University of Medical Sciences, 344 participated in completion of the Inventory of School Motivation (ISM), comprising 43 items and measuring eight aspects of motivation. The gold standard for academic achievement was their average academic marks at pre-clinical and clinical levels. Data were computer analyzed by running a couple of descriptive and analytical tests including Pearson Correlation and Student's t-student. Higher motivation scores in areas of competition, effort, social concern, and task were accompanied by higher average marks at pre-clinical as well as clinical levels. However, the latter ones showed greater motivation for social power as compared to the former group. Task and competition motivation for boys was higher than for girls. In view of our observations, students' academic achievement requires coordination and interaction between different aspects of motivation.

Managing the academic talent void: Investigating factors in academic turnover and retention in South Africa

Directory of Open Access Journals (Sweden)

Marguerite Theron

2014-04-01

Research purpose: This study aimed to investigate the factors that influence turnover and retention of academic and to validate the developed talent retention diagnostic tool for use in South African higher education institutions. Motivation for the study: Limited research currently exists on the retention factors of academic staff in the South African context. Research approach, design and method: Using an investigative quantitative research approach, the tool was administered to a convenience sample of academics (n = 153 in 13 higher education institutions. Main findings: The results showed an array of distinguishing turnover and retention factors and proved the tool to be a valid and reliable measure. Over half the respondents indicated slight to strong dissatisfaction with compensation and performance management practices. Significantly, 34% indicated that they considered exiting their academic institution, citing unhappiness about compensation, as the most likely reason, whilst 74.5% have previously looked for another job. Practical/managerial implications: The research highlights key areas (i.e. compensation, emotional recognition, a bonus structure that reflects employee contribution, performance management systems, mentorship and career development opportunities that higher education should attend to if they want to retain their key and talented academic staff. Contribution/value-add: The results contribute to new knowledge on the factors that contribute to turnover and retention of academic staff and present a valid and reliable measure to assess these retention factors.

Academic self-concept, autonomous academic motivation, and academic achievement : mediating and additive effects

OpenAIRE

Guay, Frédéric; Ratelle, Catherine; Roy, Amélie; Litalien, David

2010-01-01

Three conceptual models were tested to examine the relationships among academic self-concept, autonomous academic motivation, and academic achievement. This allowed us to determine whether 1) autonomous academic motivation mediates the relation between academic self-concept and achievement, 2) academic self-concept mediates the relation between autonomous academic motivation and achievement, or 3) both motivational constructs have an additive effect on academic achievement. A total of 925 hig...

Academic anxiety, academic procrastination, and parental involvement in students and their parents.

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Milgram, N; Toubiana, Y

1999-09-01

The study investigated the relationship between academic anxiety and procrastination in children and parents, and parents' direct involvement in their children's schoolwork. Children reported their current anxiety and procrastination and parents reported their anxiety and procrastination when they were children (a measure of indirect influence on their children's schoolwork habits), and on their current involvement in their children's schoolwork (a measure of direct influence). Self-report measures were administered to 354 Israeli adolescents (ages 13, 14, and 16) and their parents. Students were less anxious about homework than the other academic assignments. Older adolescents were less anxious about their schoolwork overall and procrastinated more than younger on homework. Parents of late adolescents were less involved in their children's schoolwork than parents of younger adolescents. Parents participated equally in school-related interactions that demanded high investment of time and effort, but mothers engaged more than fathers in low investment activities. These direct and indirect parental influences on their children's procrastination were of low magnitude overall, but appeared relatively stronger for mothers. The more students were anxious about preparing for examinations and writing papers, the more they procrastinated on these assignments, confirming the appraisal-anxiety avoidance (AAA) model. The inverse relationship of anxiety and procrastination with regard to homework led to our making a post hoc distinction between task-centred and consequence-centred anxiety.

Pharmaceutical speakers' bureaus, academic freedom, and the management of promotional speaking at academic medical centers.

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Boumil, Marcia M; Cutrell, Emily S; Lowney, Kathleen E; Berman, Harris A

2012-01-01

Pharmaceutical companies routinely engage physicians, particularly those with prestigious academic credentials, to deliver "educational" talks to groups of physicians in the community to help market the company's brand-name drugs. Although presented as educational, and even though they provide educational content, these events are intended to influence decisions about drug selection in ways that are not based on the suitability and effectiveness of the product, but on the prestige and persuasiveness of the speaker. A number of state legislatures and most academic medical centers have attempted to restrict physician participation in pharmaceutical marketing activities, though most restrictions are not absolute and have proven difficult to enforce. This article reviews the literature on why Speakers' Bureaus have become a lightning rod for academic/industry conflicts of interest and examines the arguments of those who defend physician participation. It considers whether the restrictions on Speakers' Bureaus are consistent with principles of academic freedom and concludes with the legal and institutional efforts to manage industry speaking. © 2012 American Society of Law, Medicine & Ethics, Inc.

Academic Advising and Potential Litigation.

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Schubert, Arline F.; Schubert, George W.

1983-01-01

Issues in tort and contract law and recent experiences in litigation that influence the academic adviser's responsibility are outlined, including negligence, nondisclosure and misrepresentation, defamation, written and oral contracts, and the adviser as an agent of the institution. Specific areas of adviser vulnerability are noted. (MSE)

Influence of Marital Stressors on Role Performance of Married Academic Women in Tertiary Institutions in Cross River State and Need for Counselling Therein

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Okpechi, Philip A.; Usani, Michael Okoi

2015-01-01

This study investigated the influence of marital stressors on role performance of married academic women of tertiary institutions in Cross River State. In order to accomplish the purpose of the study, two objectives and corresponding two hypotheses were postulated to guide the study. The survey research design was adopted in the study. A total of…

Academic learning for specialist nurses: a grounded theory study.

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Millberg, Lena German; Berg, Linda; Brämberg, Elisabeth Björk; Nordström, Gun; Ohlén, Joakim

2014-11-01

The aim was to explore the major concerns of specialist nurses pertaining to academic learning during their education and initial professional career. Specialist nursing education changed in tandem with the European educational reform in 2007. At the same time, greater demands were made on the healthcare services to provide evidence-based and safe patient-care. These changes have influenced specialist nursing programmes and consequently the profession. Grounded Theory guided the study. Data were collected by means of a questionnaire with open-ended questions distributed at the end of specialist nursing programmes in 2009 and 2010. Five universities were included. Further, individual, pair and group interviews were used to collect data from 12 specialist nurses, 5-14 months after graduation. A major concern for specialist nurses was that academic learning should be "meaningful" for their professional future. The specialist nurses' "meaningful academic learning process" was characterised by an ambivalence of partly believing in and partly being hesitant about the significance of academic learning and partly receiving but also lacking support. Specialist nurses were influenced by factors in two areas: curriculum and healthcare context. They felt that the outcome of contribution to professional confidence was critical in making academic learning meaningful. Copyright © 2014 Elsevier Ltd. All rights reserved.

Stability improvement of wind turbine penetrated using power system stabilizer (PSS) on South Sulawesi transmission system

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Siswanto, Agus; Gunadin, Indar Chaerah; Said, Sri Mawar; Suyuti, Ansar

2018-03-01

The purpose of this research is to improve the stability of interconnection of South Sulawesi system caused by penetration new wind turbine in Sidrap area on bus 2 and in Jeniponto area on bus 34. The method used in this research was via software Power System analysis Toolbox (PSAT) under MATLAB. In this research, there are two problems that are evaluated, the stability of the system before and after penetration wind turbine into the system South Sulawesi system. From the simulation result shows that penetration of wind turbine on bus 2 Sidrap, bus 37 Jeniponto give effect oscillation on the system. The oscillation was damped by installation of Power System Stabilizer (PSS) on bus 29 area Sungguminasa, that South Sulawesi system stable according to normal condition.

Cognitive Determinants of Academic Performance in Nigerian Pharmacy Schools

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Sansgiry, Sujit S.; Ukwe, Chinwe V.

2015-01-01

Objective. To evaluate cognitive factors that might influence academic performance of students in Nigerian pharmacy schools. Methods. A cross-sectional, multi-center survey of Nigerian pharmacy students from 7 schools of pharmacy was conducted using 2 validated questionnaires measuring cognitive constructs such as test anxiety, academic competence, test competence, time management, and strategic study habits. Results. Female students and older students scored significantly better on time management skills and study habits, respectively. Test anxiety was negatively associated with academic performance while test competence, academic competence, and time management were positively associated with academic performance. These 4 constructs significantly discriminated between the lower and higher performing students, with the first 2 contributing to the most differences. Conclusion. Test and academic competence, test anxiety, and time management were significant factors associated with low and high academic performance among Nigerian pharmacy students. The study also demonstrated the significant effects of age, gender, and marital status on these constructs. PMID:27168614

Cognitive Determinants of Academic Performance in Nigerian Pharmacy Schools.

Science.gov (United States)

Ubaka, Chukwuemeka M; Sansgiry, Sujit S; Ukwe, Chinwe V

2015-09-25

Objective. To evaluate cognitive factors that might influence academic performance of students in Nigerian pharmacy schools. Methods. A cross-sectional, multi-center survey of Nigerian pharmacy students from 7 schools of pharmacy was conducted using 2 validated questionnaires measuring cognitive constructs such as test anxiety, academic competence, test competence, time management, and strategic study habits. Results. Female students and older students scored significantly better on time management skills and study habits, respectively. Test anxiety was negatively associated with academic performance while test competence, academic competence, and time management were positively associated with academic performance. These 4 constructs significantly discriminated between the lower and higher performing students, with the first 2 contributing to the most differences. Conclusion. Test and academic competence, test anxiety, and time management were significant factors associated with low and high academic performance among Nigerian pharmacy students. The study also demonstrated the significant effects of age, gender, and marital status on these constructs.

Electronic Resource Expenditure and the Decline in Reference Transaction Statistics in Academic Libraries

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Dubnjakovic, Ana

2012-01-01

The current study investigates factors influencing increase in reference transactions in a typical week in academic libraries across the United States of America. Employing multiple regression analysis and general linear modeling, variables of interest from the "Academic Library Survey (ALS) 2006" survey (sample size 3960 academic libraries) were…

The Influence of Dispositional Optimism and Gender on Adolescents' Perception of Academic Stress

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Huan, Vivien S.; Yeo, Lay See; Ang, Rebecca P.; Chong, Wan Har

2006-01-01

This study investigated the role of optimism together with gender, on students' perception of academic stress. Four hundred and thirty secondary school students from Singapore participated in this study and data were collected using two self-report measures: the Life Orientation Test and the Academic Expectation Stress Inventory. Results revealed…

Pathophysiological appraisal of a rat model of total hepatic ischemia with an extracorporeal portosystemic shunt.

Science.gov (United States)

Suzuki, S; Nakamura, S; Sakaguchi, T; Mitsuoka, H; Tsuchiya, Y; Kojima, Y; Konno, H; Baba, S

1998-11-01

Animal models of total hepatic ischemia (THI) and reperfusion injury are restricted by concomitant splanchnic congestion. This study was performed to determine the requirement suitable for an extracorporeal portosystemic shunt (PSS) to maintain the intestinal integrity in a rat model of THI. Using a polyethylene tube (0.86 or 1 mm i.d.), PSS was placed between the mesenteric and jugular veins. Comparison was done between THI models with or without PSS and a partial ischemia model with hepatectomy of the nonischemic lobes. Well-tolerated hepatic ischemic period, portal pressure after 10 min of hepatic ischemia, portal endotoxin levels at 1 h after reperfusion, histological features of the small bowel just before reperfusion, and local jejunal and ileal blood hemoglobin oxygen saturation index (ISO2) were compared among the models. Animals without PSS poorly tolerated 30 min of THI. Animals receiving THI with PSS or partial hepatic ischemia tolerated a longer ischemic period (60 min) with a significantly higher small bowel ISO2, lower portal pressure and endotoxin levels (P tube as well as partial hepatic ischemia were significantly lower than those after THI with PSS using a 0.86-mm i.d. tube. THI with PSS using a 1-mm i.d. tube was strikingly similar to partial hepatic ischemia in the pathophysiological profile during hepatic ischemia. PSS with a tube 1 mm or more in inner diameter offers pathophysiological advantages in experiments on THI and reperfusion. Copyright 1998 Academic Press.

Changing academic roles and shifting gender inequalities: a case analysis of the influence of the teaching-research nexus on the academic career prospects of female academics in The Netherlands

NARCIS (Netherlands)

Leisyte, Liudvika; Hosch-Dayican, Bengü

2014-01-01

The purpose of this study is to gain an understanding of the change in academic roles for female academics and the implications of this change for their career opportunities. In this article, we therefore aim to answer the following research questions: (1) How have the changes introduced by the new

Influence of the motivational class climate on adolescents’ school engagement and their academic achievement

Directory of Open Access Journals (Sweden)

Melchor GUTIÉRREZ

2017-06-01

Full Text Available The scientific literature provides empirical evidence on the relationship between school engagement and numerous important variables of the adolescents’ educational context. The school engagement has been related, among other important constructs, with burnout of both teachers and students, school performance, satisfaction with the school, behavioral disruption, goal orientation and motivational climate in the classroom. Because of it, the aim of this study was to analyze the relationship between perceived motivational class climate and students’ academic achievement, with school engagement acting as a mediator. A sample of 2028 teenagers completed various instruments to measure the perception of motivational climate, perceived basic psychological needs satisfaction, perceived autonomy support provided by the teacher, and academic achievement. The data were analyzed using a structural equation model with observed variables (path analysis. The results have shown a significant relationship between motivational climate and school engagement, and of this with academic achievement. It should also be highlighted the direct relationship of perceived competence and perceived autonomy support with perception of academic success. Of the three variables to be predicted (Portuguese and Mathematics marks and Academic success, the largest percentage of variance explained was the one of academic success. The results are discussed within the framework of achievement goal theory, the self-determined motivation, and in terms of contributing practical issues to adolescents’ teaching-learning process.

Factors Influencing Academic Performance Of Standard Eight Girls In National Examinations In Public Primary Schools A Case Of Matungu Division.

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Oparanya Wamukoya Windrick

2015-06-01

Full Text Available ABSTARCT This study is designed to establish the factors influencing academic of standard eight girls in public primary schools in National exams in Matungu division. The researcher aimed at finding out why there is increased low performance of girls in public schools despite the fact that they are assessed through periodic performance tests do continuous assessment tests CATS midterm carry out tuition and the provision of free primary education which is aimed at improving academic performance. This study adapted a descriptive survey design as a major method of research where data was collected by the researcher members of a population under study. The target population comprised of Head teachers teachers pupils parents and parent schools representatives. Purposive sampling and simple random technique were used. Data was collected by use of questionnaires and interview guides. Data was analyzed by use of descriptive statistics constituting frequencies and percentages.The study established that girls were exposed to harsh school environmental conditions they walked long distances to school schools lacked facilities like toilets libraries and were exposed to male pest teachers. There were also teacher factors like training teacher shortage and motivation that affected girls performance.The study came up with recommendations for improvement of girls academic performance. More public schools should be build to reduce on distance and also overpopulation. The ministry of Education should monitor and evaluate the academic performance of girls in rural areas. The government should put up strict rules on pest teachers. The ministry should hire more teachers.

Predicting Academic Achievement from Classroom Behaviors

OpenAIRE

Flynt, Cynthia J.

2008-01-01

PREDICTING ACADEMIC ACHIEVEMENT FROM CLASSROOM BEHAVIORS by Cynthia J. Flynt Nancy Bodenhorn & Kusum Singh, Co-Chairs Counselor Education (ABSTRACT) This study examined the influence of behaviors exhibited in the classroom on reading and math achievement in the first, third and eighth grades; and the influence of teacher perceptions on reading and math achievement of African-Americans versus White students and male versus female students. Lastly, the study examined te...

Influence of serum percentage on the behavior of Wharton's jelly mesenchymal stem cells in culture.

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Harmouch, C; El-Omar, R; Labrude, P; Decot, V; Menu, P; Kerdjoudj, H

2013-01-01

Mesenchymal stem cells (MSCs) are multipotent cells able to differentiate into several lineages with valuable applications in regenerative medicine. MSCs differentiation is highly dependent on physicochemical properties of the culture substrate, cell density and on culture medium composition. In this study, we assessed the influence of fetal bovine serum (FBS) level on Wharton's jelly (WJ)-MSCs behavior seeded on polyelectrolyte multilayer films (PEMF) made of four bilayers of poly-allylamine hydrochloride (PAH) as polycation and poly-styrene sulfonate (PSS) as polyanion. MSCs isolated from WJ by explants method were amplified until the third passage. Their phenotypic characterization was performed by flow cytometry analyses. MSCs were seeded on PEMF, in Endothelial growth medium-2 (EGM-2) supplemented by either 5% or 2% FBS. Cell's behavior was monitored for 20 days by optical microscopy and immunofluorescence. Until 2 weeks on glass slides, no difference was observed whatever the FBS percentage. Then with 5% FBS, MSCs formed three-dimensional spheroids on PSS/PAH after 20 days of culture with a nuclear aggregate. Whereas, with 2% FBS, these spheroids did not appear and cells grown in 2D conserved the fibroblast-like morphology. The decrease of FBS percentage from 5% to 2% avoids 3D cell spheroids formation on PAH/PSS. Such results could guide bioengineering towards building 2D structures like cell layers or 3D structures by increasing the osteogenic or chondrogenic differentiation potential of MSCs.

Psychopathological factors that can influence academic achievement in early adolescence: a three-year prospective study.

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Voltas, Núria; Hernández-Martínez, Carmen; Aparicio, Estefania; Arija, Victoria; Canals, Josefa

2014-12-30

This three-phase prospective study investigated psychosocial factors predicting or associated with academic achievement. An initial sample of 1,514 school-age children was assessed with screening tools for emotional problems (Screen for Childhood Anxiety and Related Emotional Disorders; Leyton Obsessional Inventory-Child Version; Children's Depression Inventory). The following year, 562 subjects (risk group/without risk group) were re-assessed and attention deficit/hyperactivity disorder (ADHD) was assessed. Two years later, 242 subjects were followed, and their parents informed about their academic achievement. Results showed that early depression (phase 1 B = -.130, p = .001; phase 1 + phase 2 B = -.187, p anxiety symptoms (phase 1 + phase 2 B = -1.721, p = .018), and ADHD were predictors of lower academic achievement (phase 1 + phase 2 B = -3.415, p = .005). However, some anxiety symptoms can improve academic achievement (Social phobia B = .216, p = .018; Generalized anxiety B = .313, p academic achievement. We can conclude that in the transition period to adolescence, school-health professionals and teachers need to consider the emotional issues of students to avoid unwanted academic outcomes.

Links between Parenting Styles, Parent-Child Academic Interaction, Parent-School Interaction, and Early Academic Skills and Social Behaviors in Young Children of English-Speaking Caribbean Immigrants

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Roopnarine, Jaipaul L.; Krishnakumar, Ambika; Metindogan, Aysegul; Evans, Melanie

2006-01-01

This study examined the influence of parenting styles, parent-child academic involvement at home, and parent-school contact on academic skills and social behaviors among kindergarten-age children of Caribbean immigrants. Seventy immigrant mothers and fathers participated in the study. Hierarchical regression analyses revealed that fathers'…

The Moderating Role of Anxiety in Predicting Academic Achievement in Children

OpenAIRE

Bodas, Jaee

2003-01-01

The present study examined the relationship between anxiety and academic achievement in a sample of clinic-referred children. Specifically, the study investigated whether anxiety contributed to the prediction of academic achievement above and beyond the influence of IQ. Furthermore, the study explored whether anxiety moderated the already established relationship between IQ and academic achievement. In the present study, the WISC-III Verbal IQ, the RCMAS factors of physiological anxiety (i.e....

Facebook and Academic Performance: A Positive Outcome

OpenAIRE

González Ramírez, María Reyes; Gascó Gascó, José Luis; Llopis Taverner, Juan

2016-01-01

The objective sought with the present paper consists in analyzing the literature about Facebook in order to know the conclusions of the different works with regard to its influence on those results. The examination of 37 papers devoted to this thematic area allows us to know which journals publish more about the impacts that Facebook has on academic performance, which data collection methods are more often used, which topics emerge in parallel to the use of Facebook in the academic context, a...

Transfer students in STEM majors at a Midwestern University: Academic and social involvement factors that influence student success

Science.gov (United States)

Lopez, Carlos

There is soon-to-be a shortage of qualified U.S. workers in science, technology, engineering, and mathematics (STEM). As a result, many science-related jobs are being filled by technically-skilled foreign workers. If the U.S wants to maintain its global economic leadership, then it must ensure a continuous growth of highly-trained individuals in STEM disciplines. Therefore, American institutions of higher education, including community colleges, must identify potential factors that contribute to the lack of interest in STEM majors, as well as the low rate of success of students who enter STEM majors but struggle to finish their degrees. The purpose of this study was to ascertain the perceptions of community college transfer students who are pursuing bachelor degrees in STEM majors at Iowa State University (ISU). What were their transfer experiences and what influenced their academic success in STEM. Participants were encouraged to share their transfer experiences while at the community college as well as their experiences on the ISU campus. They were also asked about their level of academic involvement, their relationships with faculty, and their participation in peer group activities prior to and after transferring. The research design included both quantitative and qualitative components, which provided an in-depth look at the experiences of STEM non-engineering and engineering students. Quantitative data include students' background characteristics, demographic information, and college activities at the community college and ISU. Qualitative data were used to illuminate students' overall transfer experience and their successful journey in STEM fields. The combination of quantitative and qualitative methods allowed a better understanding of the strategies students put into practice once they transfer from a community college to a four-year institution in pursuit of a STEM bachelor's degree. The results of this study suggest that there is an association among the

Understanding wider environmental influences on mentoring: Towards an ecological model of mentoring in academic medicine

Directory of Open Access Journals (Sweden)

Dario Sambunjak

2015-05-01

Full Text Available Mentoring is a complex developmental relationship that contributes to individual growth and career advancement in different areas of human activity, including academic medicine. This article describes a broader environmental milieux in which mentoring occurs and considers the ways in which the environmental factors may affect the process and outcomes of mentoring. An ecological model of mentoring is proposed that takes into account various factors broadly operating at three contextual levels. The first is societal or “macro” level, which implies cultural, economic, and political factors. The second is institutional or “meso” level, consisting of a system-related factors such as field and discipline characteristics, and government policies, and b organization-related factors such as mentoring climate, reward structure, and work design. The third contextual level relates to intrapersonal and interpersonal characteristics of mentor-mentee dyads. If mentoring dyad is viewed as the focal point, societal and institutional levels may be labeled as “external”, and personal level as “internal”. The conceptual diversity and methodological challenges in the study of mentoring need to be acknowledged, but should not be an excuse to leave the external contextual elements out of the researchers’ horizon, as they inevitably shape and modify the mentoring relationships. Conclusion. Model presented in this article offers a holistic view of mentoring in academic medicine that may help one comprehend and appreciate the complexity of influences on mentoring, and inform the future research agenda on this important topic.

Generational influences in academic emergency medicine: teaching and learning, mentoring, and technology (part I).

Science.gov (United States)

Mohr, Nicholas M; Moreno-Walton, Lisa; Mills, Angela M; Brunett, Patrick H; Promes, Susan B

2011-02-01

For the first time in history, four generations are working together-traditionalists, baby boomers, generation Xers (Gen Xers), and millennials. Members of each generation carry with them a unique perspective of the world and interact differently with those around them. Through a review of the literature and consensus by modified Delphi methodology of the Society for Academic Emergency Medicine Aging and Generational Issues Task Force, the authors have developed this two-part series to address generational issues present in academic emergency medicine (EM). Understanding generational characteristics and mitigating strategies can help address some common issues encountered in academic EM. Through recognition of the unique characteristics of each of the generations with respect to teaching and learning, mentoring, and technology, academicians have the opportunity to strategically optimize interactions with one another. © 2011 by the Society for Academic Emergency Medicine.

The Relation between Binge Drinking and Academic Performance: Considering the Mediating Effects of Academic Involvement

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An, Brian P.; Loes, Chad N.; Trolian, Teniell L.

2017-01-01

Using longitudinal data from multiple institutions, we focused on the relation between binge drinking and academic performance. Binge drinking exerts a negative influence on grade point average, even after accounting for a host of precollege confounding variables. Furthermore, the number of times a student binge drinks in college is less…