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Despite considerable research on the importance of a management practice emphasizing the relational aspect such as participative management, little is known regarding the mechanism through which this relation-oriented management practice motivates public employees to cultivate pro-organizational work behavior such as organizational citizenship behavior. Using data from public employees in South Korea, this study examines the association between participative management and organizational citizenship behavior. We also explore how participative management sparks public employees to be engaged in their job, which in turn leads to higher organizational citizenship behavior. By identifying employee engagement as a mediating mechanism that links participative management and organizational citizenship behavior, this study offers insights into the role of relational management practices in public settings.

Di(9-methyl-3-carbazolyl)-(4-anisyl)amine is presented as an effective hole-transporting material suitable for application in perovskite solar cells. It is obtained by a three-step synthesis from inexpensive starting compounds. It has a relatively high glass transition temperature of 93 °C and thermal stability with 5% weight loss at 374 °C. The compound exhibits reversible double-wave electrochemical oxidation below +1.5 V and polymerization at higher potential. A mechanism for its oxidation is proposed based on electrochemical impedance and electron spin resonance spectroscopy investigations, ultraviolet-visible-near-infrared absorption spectroelectrochemistry results, and density functional theory-based calculations. Vacuum-deposited films of the compound are characterized by a low ionization potential of 5.02 ± 0.06 eV and hole mobility of 10-3 cm2/(Vs) at an electric field of 4 × 105 V/cm. The newly synthesized compound has been used to fabricate dopant-free hole-transporting layers in perovskite solar cells. A power conversion efficiency of 15.5% was achieved in a preliminary study.

Emerging technologies in solar energy will be critical in enabling worldwide society in overcoming the present energy challenges and reaching carbon net zero. Inefficient and unstable charge transport materials limit the current emerging energy conversion and storage technologies. Low-dimensional coordination polymers represent an alternative, unprecedented class of charge transport materials, comprised of molecular building blocks. Here, we provide a comprehensive study of mixed-valence coordination polymers from an analysis of the charge transport mechanism to their implementation as hole-conducting layers. CuII dithiocarbamate complexes afford morphology control of 1D polymer chains linked by (CuI2X2) copper halide rhombi. Concerted theoretical and experimental efforts identified the charge transport mechanism in the transition to band-like transport with a modeled effective hole mass of 6me. The iodide-bridged coordination polymer showed an excellent conductivity of 1 mS cm−1 and a hole mobility of 5.8 10−4 cm2 (V s)−1 at room temperature. Nanosecond selective hole injection into coordination polymer thin films was captured by nanosecond photoluminescence of halide perovskite films. Coordination polymers constitute a sustainable, tunable alternative to the current standard of heavily doped organic hole conductors.

Lead bromide perovskite with high bandgap and good stability has aroused broad interest for utilization in perovskite solar cells (PSCs) with high photovoltage, especially as a candidate for the front cell of tandem solar cells. However, the efficiency of lead bromide PSCs is still much lower than the standard lead iodide PSCs, and the defects in the perovskite are one of the main limiting factors hindering device performance. The construction of a 2D/3D perovskite interface is an effective way to passivate the interfacial defects and achieve efficient and stable PSCs. Herein, a facile and effective phenethylammonium bromide (PEABr) treatment method was applied to build a 2D/3D perovskite interface in FAPbBr(3) solar cells. An ultrathin layer of 2D PEA(2)PbBr(4) perovskite was successfully fabricated on the surface of 3D FAPbBr(3) perovskite by depositing the PEABr solution on the 3D perovskite films. The 2D perovskite layer significantly passivated the interfacial defects, leading to enhancement of power conversion efficiency from 7.7% to 9.4% and fill factor from 67.6% to 77.6%. Moreover, the hydrophobic alkyl chain in the PEA cation improved the moisture tolerance of the perovskite and significantly increases the solar cell stability. Additionally, the PEABr treatment strategy was successfully utilized for preparing semitransparent 2D/3D FAPbBr(3) perovskite solar cells.

In this work, efficient and bending durable flexible perovskite solar cells are obtained by modification of the perovskite film surface with 1- dodecanethiol (DT) followed by drop-casting of pre-dispersed thin nanosheets of MoS2. Our results show an enhancement in efficiency of the flexible device after the interface modification and revealed that the DT and MoS2 modified device recovers completely its initial values of PCE and FF, current density, and open-circuit voltage after 300 bending cycles while the standard device resembles only 50% of its PCE. Following a standard light cycling protocol for unencapsulated devices, it revealed an apparent PCE drop of the standard device up to 32% of its maximum value while the modified device recovers 95% of its highest PCE value. Different characterization methods suggest that the surface modification method induces hydrophobicity as well as significantly reduces the interface trap density.

Lead bromide perovskite solar cells (PSCs) have attracted increasing interest partly because of the high open-circuit voltage that has been obtained. Here, we present a simple way to prepare PSCs based on formamidinium lead tribromide, FAPbBr(3), by adding methylammonium chloride and methylammonium bromide into the precursor solution. With this method, high-quality and pin-hole free perovskite films with large crystal sizes were prepared. These additives result in a power conversion efficiency (PCE) of 7.9%, almost free of hysteresis, for a device on a rigid glass substrate. The first flexible lead bromide PSC is also prepared in this work and the flexible PSC exhibited a high PCE of 5.0%.

Despite the rapid development of perovskite solar cells (PSCs) toward commercialization, the toxic lead (Pb) ions in PSCs pose a potential threat to the environment, health and safety. Managing Pb via recycling represents a promising approach to mitigating its toxicity. However, managing Pb from commonly used organic solvents has been challenging due to the lack of suitable Pb adsorbents. Here, we report a new adsorbent for both separation and recovery of Pb from PSC pollutants. The synthesized iron-incorporated hydroxyapatite possesses a strongly negatively charged surface that improves electrostatic interaction through surface-charge delocalization, thus leading to enhanced Pb adsorption. We demonstrate the feasibility of a complete Pb management process, including the purification of Pb-containing non-aqueous solvents below 15 parts per 109, a level compliant with the standards of the US Environmental Protection Agency, as well as recycling of 99.97% of Pb ions by forming lead iodide. The most-efficient solar cells use Pb-based halide perovskites; however, their toxicity poses environmental and health risks. Here, the authors report an adsorbent that allows for sustainable Pb management in these devices.

Perovskite solar cells (PSCs), which have surprisingly emerged in recent years, are now aiming at commercialization. Rapid, low-temperature, and continuous fabrication processes that can produce high-efficiency PSCs with a reduced fabrication cost and shortened energy payback time are important challenges on the way to commercialization. Herein, we report a reactive ion etching (RIE) method, which is an ultrafast room-temperature technique, to fabricate mesoporous TiO2 (mp-TiO2) as an electron transport layer for high-efficiency PSCs. Replacing the conventional high-temperature annealing process by RIE reduces the total processing time for fabricating 20 PSCs by 40%. Additionally, the RIE-processed mp-TiO2 exhibits enhanced electron extraction, whereupon the optimized RIE-mp-TiO2-based PSC exhibits a power conversion efficiency (PCE) of 19.60% without J-V hysteresis, when the devices were optimized with a TiCl4 surface treatment process. Finally, a flexible PSC employing RIE-mp-TiO2 is demonstrated with 17.29% PCE. Considering that the RIE process has been actively used in the semiconductor industry, including for the fabrication of silicon photovoltaic modules, the process developed in this work could be easily applied toward faster, simpler, and cheaper manufacturing of PSC modules.

For commercialization of perovskite solar cells (PSCs), it is important to substitute the alternative electrode for Au to decrease the unit cost. From the early stage, Ag exhibits a potential to be a good counter electrode in PSCs; however, there is an abnormal s-shaped J-V curve with the Ag electrode, and it is recovered as time passes. The perception of the aging-induced recovery process and refutation of the raised stability issues are required for commercial application of Ag electrodes. Herein, we compared the aging effect of PSCs with Ag and Au electrodes and found that only devices with Ag electrodes have a dramatical aging-induced recovery process. We observed the change of photoelectronic properties only in the devices with Ag electrodes as time passes, which mainly contributes to recovery of the s-shaped J-V curve. We verified the work function change of an aged Ag electrode and its mechanism by photoelectron spectroscopy analysis. By comparing the light stability under 1 sun intensity illumination, we can assure the practical stability of Ag electrodes in case of being encapsulated. This work suggests the profound understanding of the aging-induced recovery process of PSCs and the possibility of commercial application of Ag electrodes.

Drawing on the social-ecological systems perspective of health, this study explores whether the deteriorating trend of immigrant health over time differs depending on immigrants' pre-migration macro-level factors in their birth country. Using the Household, Income, and Labor Dynamics in Australia survey (N = 1,847), we conducted an HLM analysis to examine the association among GDP per capita in the birth country, length of stay, and immigrants' health status post-migration. Support was found for both the negative association between the length of stay and health and the positive association between the GDP of the birth country and health. The negative association between length of stay and health was stronger among immigrants from low GDP countries compared to those from high GDP countries. Our findings suggest the importance of the population-level characteristics of the birth country in understanding healthy immigrant effect post-migration.

Mesoporous TiO2 (mp-TiO2) layers are commonly used as electron transport layers in perovskite solar cells, which help to extract electrons from the perovskite light-absorbing layer and transport them to the electrodes. We investigated the effects of the layer thickness of mp-TiO2 and particle size of TiO2 on photovoltaic properties, in terms of the surface area of the mp-layer and the interfacial areas of the TiO2 nanoparticles in the mp-layer. Various mp-TiO2 layers with thicknesses of 150, 250, and 400 nm and particle sizes of 25 nm and 41 nm were prepared to compare the photovoltaic properties of such layer-containing perovskite solar cells. Time-resolved photoluminescence decay and impedance studies showed that interfacial resistance as well as perovskite-to-TiO2 charge injection are important factors affecting photovoltaic performance. The deterioration of the photovoltaic parameters with increasing TiO2/TiO2 interfacial area also confirms that the interfacial series resistance that arises from these connections should be reduced to enhance the performance of mesoscopic perovskite solar cells.

We report the amorphous quaternary oxide, indium-tin-silicon-oxide (ITSO), thin film as a new electron-transport layer (ETL) for perovskite solar cells (PSCs). ITSO thin films are grown by magnetron co-sputtering indium-tin-oxide (ITO) and silicon oxide (SiO2) on commercial transparent conducting oxide (ITO) thin films at room temperature. As Si content increases (0–53.8 at%) the optical bandgap increases by over 1.5 eV and the electrical resistivity increases by six orders mainly because of the carrier concentration decrease. Consequently, the ITSO electronic structure depends largely on Si content. PSCs employing ITSO thin films as ETLs were fabricated to evaluate the effect of Si content on device performances. Si content influenced the shunt and series resistance. The optimized device was obtained using an ITSO film with 33.0 at% Si content, exhibiting 14.50% power-conversion efficiency. These results demonstrate that ITSO films are promising for developing efficient PSCs by optimizing the growing process and/or In/Sn/Si/O compositions. This approach can reduce PSC manufacturing process time and costs if ITO and ITSO are grown together by continuous sequential sputtering in a dual gun (ITO and SiO2) chamber.

Surface modification of perovskite films using a combination of 1-dodecanethiol (DT) and MoS2 nanosheets is investigated for perovskite solar cells. This surface modification is studied for two different types of perovskites, one with triple cations (CsFAMA) and one with double cations (FAMA), resulting in solar cell devices with power conversion efficiency (PCE) values of 18-19 and >20%, respectively. In both cases, stability enhancement is observed with DT and MoS2 surface modification using three different stability tracking protocols. The results reveal that by including DT and MoS2, the device retains 92% of its highest efficiency after 2200 h in dark (in air), while the standard device retained only 72%. Moreover, after light cycling, the device with DT and MoS2 retained 80%, and the standard device retained 55% of its maximum PCE. Moreover, these surface modifications gave rise to 58% decrease in the number of short-circuited devices and more reproducible results. Different characterizations revealed that the stability and efficiency enhancement is mainly due to reduced interface trap densities, improved charge transfer, and longer charge carrier lifetime. Moreover, the DT and MoS2 modifications induce hydrophobicity with an average contact angle over 80 degrees.

The cesium cation (Cs+) is widely used as a dopant for highly efficient and stable formamidinium lead tri-halide perovskite (FAPbX3, X = I, Br, Cl) solar cells. Herein, we introduce a small amount of cesium acetate (CsAc) that can effectively stabilize FAMAPbI3 under thermal- and light illumination-stress. We show that incorporated Cs+ leads to relaxation of strain in the perovskite layer, and that Ac- forms a strong intermediate phase with PbI2, which can help the intercalation of the PbI2 film with Cs+ and cation halide (FAI, MAI, MACl) in the sequential deposition process. The addition of CsAc reduces the trap density in the resulting perovskite layers and extends their carrier lifetime. The CsAc-modified perovskite solar cells show less hysteresis phenomena and enhanced operational and thermal stability in ambient conditions. Our findings provide insight into how dopants and synthesis precursors play an important role in efficient and stable perovskite solar cells.

BACKGROUND: Problems related to ankle instability, decreased proprioceptive sensation, altered static and dynamic balance abilities are suggested as major representative factors that contribute to the recurrence of ankle sprains. OBJECTIVE: To assess the effect of a three-week intervention (intervention emphasizing diagonal eccentric contraction (IEDEC) and intervention of general exercise (IGE)) on static and dynamic balance abilities, ankle strength and joint position sense at pre- and post-intervention, and at two- and three-week post-intervention. METHODS: Twenty-five participants with ankle instability, including a history of ankle sprain and recurrent episodes of giving way, were enrolled in the study. They were randomly classified into the IEDEC group (n= 12) and the IGE group (n= 13). Dynamic balance was examined using the Y Balance Test, four-way ankle strength was measured, and the static balance was evaluated using the total displacement of the center of pressure (COP). To identify the joint position error, eversion and inversion of the ankle angle were measured. RESULTS: The results revealed significant increases in ankle dynamic stability and strength at two and three weeks post-intervention (p< 0.05). Similarly, the total displacement of the COP differed significantly over time, with a higher COP during the initial measurement than at two and three weeks intervention (p< 0.05) General balance training with IEDEC can improve position sense during ankle inversion (p< 0.05). CONCLUSION: General balance training with IEDEC improved the position sense of the inversion. Combined therapeutic intervention, such as with the manual technique, could be a beneficial approach to maximize the treatment effects.

Energy efficient synthesis providing high quality crystalline thin films are highly desired in many applications. Here we devise a non-toxic solvent approach for production of highly crystalline MAPbI3 perovskite by exploiting diffusion aggregation processes. Isopropanol solution based methylammonium lead triiodide (MAPbI3) is used in this context, where the crystal growth initiation starts in an unstable suspension far from equilibrium and the subsequent crystallization is driven by the solubility parameters. The crystal formation is monitored by scanning transmission electron microscope (STEM), observing small crystallization centers growing as time evolves to large grains with high crystal purity. Energy dispersive X-ray spectroscopy (EDS) in STEM mode revealed a Pb rich core-shell structure in newly formed grains. Nano-beam Electron Diffraction (NBED) scan defined PbI2 crystallites in the Pb rich shell with a single crystal MAPbI3 core in newly formed grains. After a week stirring, the same aggregated suspension exhibited grains with only single crystal MAPbI3 structure. The NBED analysis shows a kinetically slow transition from a core shell structure to a single crystal grain. This research presents an impactful insight on the factors that may cause sub-stoichiometric grain boundary effects which can influence the solar cell performance. In addition, the structure, morphology and optical properties of the perovskite grains have been presented. A powder of highly crystalline particles was subsequently prepared by evaporation of the solvent in a low-vacuum oven. Thin film MAPbI3 solar cells were fabricated by dissolving the powder and applying it in a classical fabrication route. The MAPbI3 solar cells gave a champion efficiency of 20% (19.9%) and an average efficiency at approximately 17% with low hysteresis effects. Here a strategy to manufacture the material structure without toxic solvents is highlighted. The single-crystal growth devised here opens both for shelf storage of materials as well as a more flexible manufacturing of devices. The process can likely be extended to other fields, where the intermediate porous framework and large surface area would be beneficial for battery or super capacitor materials.

This study examined the effects of group exercise program on health conditions and quality of life in cerebral palsy. Adults with cerebral palsy in their 20’s who participated in the evaluation of measurement tools prior to and following the experiment. The control group was engaged in manual exercise for the range of joint movement and extension exercise for arms, legs and trunk, and experimental group performed group exercise program including boccia exercise. The health condition and quality of life of the experimental group were significantly increased after intervention (.05

The purpose of this study was to examine the immediate effect of neck stabilization exercise and Swiss ball exercise on the recovery from the fatigue of neck muscles induced. The turtleneck posture was set artificially by using Smartphone with healthy adults. Repetitively measured ANOVA was executed to examine the changes in the muscle fatigue of sternocleidomastoid, upper trapezius, and splenius capitis among three-time intervals (at the time of general resting, work and after intervention) in the three intervention groups (neck stabilization exercise group, Swiss ball exercise group, and ordinary rest group). There were no significant differences in the changes of fatigue of sternocleidomastoid muscle among all three intervention groups at the time of general resting, work and after intervention (p>.05). Although there was no significant difference in the changes in the fatigue of upper trapezius and splenius capitis muscles between the intervention groups at the time of general resting and work (p>.05), there was the significant difference between the three intervention groups at the time of work and after intervention (p>.05). This study suggest that Swiss ball exercise is more effective in reducing the muscular fatigue of the neck and shoulder at a turtleneck posture than neck stabilization exercise.

This study was conducted to examine the effects of the application of familycentered training over the 12-week period by the pediatric physiotherapist on functional balance and activities of daily living in children with cerebral palsy. Among the 26 children with cerebral palsy as the subjects were allocated to the experimental and control group. Both groups were subjected to neurodevelopmental treatment by the pediatric physiotherapist. The experimental group, participated in family-centered training program 3 times a week over a period of 12 weeks for the total of 36 sessions, functional balance and activities of daily living were verified through intergroup comparison. There was no significant difference between the outcomes prior to training and after 6 weeks of training, (p>.05) Pediatric Berg''s Balance Scale(PBS) and Functional Independence Measure for children(Wee-FIM) increased significantly from those measures after 6 weeks to those after 12 weeks of training (p

The main focus of this study was to investigate effects of lumbar central posteroanterior (PA) mobilization on isometric knee extension (IKE) ability and patellar tendon reflex amplitude (PTRA) in healthy university students. University students aged 19-26 (male; 10, female; 10) without any neurological disorders participated voluntarily and excluded the subjects with abnormal reflexes. The participation had an average body mass of 64.25±13.52 kg, an average height of 1.66±0.08m, and an average Body Mass Index (BMI) of 23.07±3.21. Every student was randomly assigned to be received squatting exercise and PA mobilization sequentially with 5 days of wash out period. IKE and PTRA were not significantly different between the two groups after the intervention. All the outcome measures were arranged into two data groups; PA mobilization and squatting exercise data group. In the PA mobilization data group, IKE and PTRA significantly increased after the intervention, however, these aspects were decreased in the squatting exercise group. These findings suggest that IKE and PTRA increase immediately after PA mobilization, therefore PA mobilization could be a valuable topic for controlled clinical trials.

Photovoltaic device based on inorganic–organic hybrid perovskite structured materials have been one of the brightest spotlights in the energy-conversion research field in recent years. However, due to their inherent properties and the architecture of the fabricated device, many defects trap states or carrier transport barriers are present at the interfaces between each functional layer and at the grain boundaries of the perovskite. These defects cause undesirable phenomena such as hysteresis and instability in the perovskite solar cells , which has slowed their commercialization. To address these issues, intensive research effort has been devoted recently to the development of passivation materials and approaches that can reduce the amount of interface and surface defect states in perovskite solar cells. Here, we have reviewed the state of the research progress in the development of passivation of different interfaces in the perovskite solar cell, including the interface (a) between transparent conductive oxide and electron transport material; (b) between the electron transport material and perovskite; (c) between the perovskite grains (grain boundaries); (d) between the perovskite and hole transport layer; (e) between the hole transport layer and electrode, and (f) between the electrode material and atmospheric environment. We also look into the prospects and challenges in the passivation of hybrid perovskite solar cells.

[Purpose] This study was conducted to examine the effects of task-specific movement patterns during resistance exercise program, which are applied to children with cerebral palsy, on respiratory functions and thickness of abdominal muscles. [Participants and Methods] This study was conducted with randomized double-blinded controlled research was pursued since it is a clinical trial with minors with disabilities as the participants. Seventeen children with cerebral palsy were randomly allocated to both experimental group and placebo group by means of simple randomized sampling. The experimental group wore weighted vest to which loaded-resistance was applied by means of sand bag while the placebo group wore weighted vest without loaded-resistance. Task-specific movement patterns during resistance exercise were performed for 40 minutes 2 times a week over a period of 12 weeks for the participants in both groups. Differences in respiratory functions and thickness of abdominal muscles measured prior to and after 12 weeks of the experiment were compared. [Results] All the measurement values for the respiratory functions and abdominal muscle thickness displayed statistically significant changes between those prior to and after the exercise in both of the experimental group and the placebo group. There were statistically significant differences in the changes prior to and following the exercise between the two groups. [Conclusion] Therefore, task-specific movement patterns in anatomical plane, diagonal patterns and combined forms during resistance exercise program on for children with cerebral palsy can be considered as an efficient intervention method in improving respiratory capacity.

Cs2AgBiBr6, has recently gained wide attention as a possible alternative to lead-halide perovskites, considering the nontoxicity and improved stability. However, this double perovskite suffers from defects, especially deep electron traps, severely hampering the photovoltaic performance. This work reports a simple method to control the double perovskite crystallization by adding volatile salts into the precursor solution. X-ray diffraction patterns reveal that the organic cation with suitable radius (such as methylammonium, MA(+)) is introduced into the perovskite lattice, forming an organic/inorganic mixed double perovskite intermediate phase. The organic salt is thereafter fully evaporated during high temperature annealing, and the all-inorganic double perovskite is obtained with dense surface and less pin-holes. From optical and electrical characterization, it is concluded that the Cs2AgBiBr6 film exhibits high quality, with higher light absorptance and emission. Reduced trap density and longer carrier lifetime are also observed. The improved Cs2AgBiBr6 film is beneficial for efficient carrier collection with suppressed defect-assisted recombination. With this strategy, a power conversion efficiency (PCE) of 2.53% is achieved for the champion Cs2AgBiBr6-based solar cell device, which is significantly higher compared to the control device with 1.43% PCE. This work is therefore helpful for further improvement of inorganic lead-free perovskite materials for optoelectronic applications.

Organic–inorganic halide perovskites (OIHPs) has emerged as promising optoelectronic materials for solar cells and light-emitting diodes. OIHPs are usually coated on a flat surface or mesoporous scaffold for the applications. Herein, we report a facile sol-gel-derived solution route for coating methylammonium lead iodide (MAPbI3) perovskite layers onto various nanoporous structures. We found that lead-acetate solution has superior infiltration property onto surface of oxide membranes, and it can easily be converted to MAPbI3 by sequential transform to PbO, PbI2, and finally MAPbI3. Excellent pore-filling and full coverage of the nanostructures with the final MAPbI3 perovskite material are demonstrated via this sol-gel-derived solution route, using mesoporous TiO2, TiO2 nanorods, and high-aspect ratio nanopores in anodic aluminum oxide membranes. Given that this sol-gel-based method fills nanopores better than other conventional coating methods for OIHPs, this method may find wide applications in nanostructured OIHPs-based optoelectronic systems.

In this study, we examine the thickness of the abdominal muscle and its activity during the performance of the three drawing-in methods. The subjects were 20 healthy male and female students in their 20s. Using ultrasonography and electromyography, the experimenter measured the thickness of the transversus abdominis (TrA) muscle, internal oblique (IO) muscle and external oblique (EO) muscle. The ultrasonography measurements for the drawing-in manoeuver (DI), abdominal bracing, and posterior pelvic tilt (PT) techniques were 0.64±0.20, 0.54±0.15, and 0.46±0.12, respectively, with significant differences for the TrA. The electromyography results of the DI, SA, and PT techniques were 4.35±1.72, 3.00±1.48, and 2.70±1.52, respectively, for the IO. There was a significant difference in the DI, SA, and PT techniques for the EO (5.10±3.30, 3.85±3.89, 2.25±1.29, respectively). The DI method activated the oblique abdominal muscles, but there was no great change in their thickness; the TrA, however, was selectively strengthened through changes in its thickness.

Coupling dissimilar oxides in heterostructures allows the engineering of interfacial, optical, charge separation/transport and transfer properties of photoanodes for photoelectrochemical (PEC) water splitting. Here, we demonstrate a double-heterojunction concept based on a BiVO4/WO3/SnO2 triple-layer planar heterojunction (TPH) photoanode, which shows simultaneous improvements in the charge transport (∼93% at 1.23 V vs RHE) and transmittance at longer wavelengths (>500 nm). The TPH photoanode was prepared by a facile solution method: a porous SnO2 film was first deposited on a fluorine-doped tin oxide (FTO)/glass substrate followed by WO3 deposition, leading to the formation of a double layer of dense WO3 and a WO3/SnO2 mixture at the bottom. Subsequently, a BiVO4 nanoparticle film was deposited by spin coating. Importantly, the WO3/(WO3+SnO2) composite bottom layer forms a disordered heterojunction, enabling intimate contact, lower interfacial resistance, and efficient charge transport/transfer. In addit...

[Purpose] This study was carried out to examine the effect of the application of group exercise program composed to induce interests and assertive participation of adults with cerebral palsy on the self-efficacy and activities of daily living, as well as to provide basic clinical data that are effective and trustworthy in enhancing the physical and emotional interaction in the future. [Subjects and Methods] Those among the 23 adult with cerebral palsy who are the subjects of research and able to participate only in the evaluation of measurement tools prior to and after the experiment were allocated to the control group while only those who can participate in the group exercise program implemented over 12 sessions were allocated to the experimental group. For the control group, a range of motion of joint exercise and stretching exercise were executed on the arms, legs and trunk, while for the experimental group, group exercise that is implemented with participation of several subjects simultaneously was executed 2 times a week with 40 minutes for each session over a period of 6 weeks for the total of 12 sessions. [Results] In both the experimental group and the control group, there were statistically significant changes in the average scores of self-efficacy and activities of daily living after the exercise in comparison to that prior to the exercise. Moreover, there were statistically significant differences in self-efficacy and activities of daily living in terms of quantity of change prior to and after the exercise between the two groups. [Conclusion] Therefore, group exercise program composed to induce physical and emotional interaction, and active participation of adults with cerebral palsy can be considered as an effective intervention method in improving their self-efficacy and activities of daily living.

Electron selective layers are important to the efficiency, stability and hysteresis of perovskite solar cells. Photo-annealing is a low-cost, roll-to-roll-compatible process that can be applied to the post-treatment fabrication of sol-gel based metal oxide layers. Here, we fabricate an amorphous titanium oxide electron selective layer at a low temperature in a dry atmosphere using a UV light annealing system and compare it with a thermal annealing process. Active oxygen species are created by using UV light to promote hydrolysis and condense the TiO2 precursor, which removes organic ligands effectively. The photo-annealed TiO2-based perovskite solar cell has a power conversion efficiency of 19.37% without hysteresis.

We report herein a facile process for the fabrication of amorphous TiO2 thin films under ambient atmosphere using thermal-assisted UV-annealing (~125 °C). The TiO2 films were prepared via spin-coating titanium diisopropoxide bis(acetylacetonate) precursor and sequential photo-annealing at various temperatures. Additional soft annealing during the UV-annealing altered the surface chemical states and electrical band structures of the amorphous TiO2 films. The UV-annealing at room temperature leads to a higher conduction band minimum level of the film and a smaller amount of hydroxyl group at the film surface, compared to the thermal-assisted (100–250 °C) UV-annealing or the thermal-only annealing (500 °C). Effects of the temperature during the UV-annealing process on photovoltaic properties were investigated by fabricating planar heterojunction perovskite cells with methylammonium lead triiodide under ambient atmosphere. At higher temperature of 100–150 °C, compared to room temperature, fill factor and power conversion efficiency were enhanced, and hysteresis in current-voltage curves were reduced. Impedance analysis demonstrates that the capacitance is significantly reduced, leading to suppressed hysteresis of the perovskite solar cells. Finally, we achieved a power-conversion efficiency of 20.36% (for the reverse scan) and a stabilized power output of 18.57% from a 125 °C -photo-annealed TiO2-based device.

Enhancing hole extraction inside the perovskite layer is the key factor for boosting photovoltaic performance. Realization of halide concentration gradient perovskite materials has been expected to exhibit rapid hole extraction due to the precise bandgap tuning. Moreover, a formation of Br-rich region on the tri-iodide perovskite layer is expected to enhance moisture stability without a loss of current density. However, conventional synthetic techniques of perovskite materials such as the solution process have not achieved the realization of halide concentration gradient perovskite materials. In this report, we demonstrate the fabrication of Br concentration gradient mixed halide perovskite materials using a novel and facile halide conversion method based on vaporized hydrobromic acid. Accelerated hole extraction and enhanced lifetime due to Br gradient was verified by observing photoluminescence properties. Through the combination of secondary ion mass spectroscopy and transmission electron microscopy with energy-dispersive X-ray spectroscopy analysis, the diffusion behavior of Br ions in perovskite materials was investigated. The Br-gradient was found to be eventually converted into a homogeneous mixed halide layer after undergoing an intermixing process. Br-substituted perovskite solar cells exhibited a power conversion efficiency of 18.94% due to an increase in open circuit voltage from 1.08 to 1.11 V and an advance in fill-factor from 0.71 to 0.74. Long-term stability was also dramatically enhanced after the conversion process, i.e., the power conversion efficiency of the post-treated device has remained over 97% of the initial value under high humid conditions (40-90%) without any encapsulation for 4 weeks.

PURPOSE: This study investigated the effects of lower limb and trunk muscles activation on seat angle and height during sit to stand and stand to sit. METHODS: Subjects were instructed to sit and stand on different angles and heights; (43cm), (48cm), (51cm) and (58cm). Measurements were conducted from sit to stand and stand to sit for external oblique, transversus abdominis, rectus femoris, vastus medialis, vastus lateralis, tibialis anterior and gastrocnemius muscle activation by surface EMG. The muscle activation was measured three times for five seconds in each posture, and the %RVC value was calculated after the exclusion of one second before and after this measurement. This calculation standardized the data from each participant so it could be comparatively analyzed. RESULTS: The external oblique, tibialis anterior, and erector spinae muscles showed significant difference in (51cm), (58cm) and (43cm), rectus femoris, in (58cm) and (43cm)(p(43cm) and (58cm), erector spinae and vastus medialis muscles showed significant difference in (51cm), (58cm) and (43cm)(P

We report a highly efficient p–i–n type planar perovskite solar cell with a hybrid PEDOT/NiOx hole-extraction layer. It has been found that the perovskite solar cell with a NiOx thin film as a hole-extraction layer generally exhibits lower fill factor compared to the conventionally used PEDOT:PSS thin film, whereas it shows higher photocurrent and photovoltage. The fill factor of the NiOx-based perovskite solar cell can be significantly improved by treating the NiOx surface with a dilute PEDOT solution. The photoluminescence quenching study and impedance spectroscopic (IS) analysis have revealed that the hole injection at the perovskite/NiOx interface is significantly facilitated with the PEDOT treatment, which should lead to the increased fill factor. As a result, the p–i–n type planar perovskite solar cell with the new hybrid hole-extraction layer exhibits a high conversion efficiency of 15.1% without the hysteresis effect.

Methods such table flow, slump and outflow time have used to be as a main evaluation criteria regards to fluidity of concrete. Since those methods mentioned above have some inaccuracies which are up to its condition of test. Studies that evaluate fluidity applying the rheology has increased its portion in this field. Meanwhile, demands for AAS binder have been increased in accordance with its demand for this market, studies for rheology of AAS binder are little though. Therefore, this paper mainly deals a rheological peculiarity of AAS binder according to its condition of W/B ratio and alkali activators. The fluidity of AAS paste was evaluated with the index of table flow and outflow time. And shear stress following its shear rate was analyzed through rheological test. Rheological parameters were deduced through this rheological test of Bingham model and analyzed its interrelation with fluidity test. As the final outcome, it proposed the interrelation among table flow, yield stress, viscosity and outflow time. In basis of this study, we would like to suggest a reference for mixing AAS mortars and concretes.

This study was executed as correlation study to investigate the correla-tion between the dimensions of diaphragm movement, and respiratory functions and pressures in accordance with the Gross Motor Function Classification System (GMFCS) levels on children with cerebral palsy as the participants. Forty-three children in the age range of 5–13 years di-agnosed with cerebral palsy as the research participants were divided into three groups (levels I, II, and III) through systematic stratified ran-dom sampling in accordance with their GMFCS levels. Pearson correla-tion analysis was executed to examine the correlation between dimen-sions of diaphragm movement, and respiratory functions and pressures in accordance with the GMFCS levels of the participants. There was no significant correlation between the dimensions of diaphragm move-ment, and respiratory functions and pressures in all of the three groups in accordance with the GMFCS levels of the participants. Therefore, it is deemed that although measurement of the dimensions of diaphragm movement of children with cerebral palsy by using diagnostic ultrason-ic M-mode imaging device can be considered as auxiliary tool in pre-dicting the breathing capabilities, it cannot be used as independent measurement equipment.

Photovoltaic technologies based on perovskite absorber materials have led this optoelectronic field into a brand-new horizon. However, the present antisolvents used in the one-step spin-coating method always encounter problems with the very narrow process window. Herein, anisole is introduced into the one-step spin-coating method, and the technology is developed to fabricate perovskite thin films with ultrawide processing window with a dimethylformamide (DMF):dimethyl sulfoxide (DMSO) ratio varying from 6:4 to 9:1 in the precursor solution, anisole dripping time ranging from 5 to 25 s, and an antisolvent volume varying from 0.1 to 0.9 mL. Perovskite thin films as large as 100 cm2 are successfully fabricated using this method. Maximum photoelectric conversion efficiencies of 19.76% for small-area (0.14 cm2 ) and 17.39% for large-area (1.08 cm2 ) perovskite solar cell devices are obtained. It is also found that there are intermolecular hydrogen-bonding forces between anisole and DMF/DMSO that play critical roles in the wide process window. These results provide a deeper understanding of the crystallizing procedure of perovskite during the one-step spin-coating process.

PURPOSE: The purpose of this study is to investigate the effects of the angles of the knee and heel-off on the muscle activity during a bridge exercise. METHODS: 15 healthy adult men and women with the balance ability and joint working range required for performing a bridge exercise participated in this study, in which 120°, 90° and 60° angles of the knee-flexion and heel-off were applied during the bridge exercise. RESULTS: Our data showed that there were significant differences in muscle activities of elector spinae and rectus abdominis when 120°and 60°angles of the knee were applied, of internal oblique when 120°and 60°were applied, and external oblique when 90°and 60°were applied. When heel-off was applied, there were significant differences in muscle activities of elector spinae and rectus abdominis when 120°and 60°were applied, of internal oblique when 120°and 60°were applied, and external oblique when 90°and 60°were applied. CONCLUSION: In this study on an application of heel-off to the bridge exercise, we showed that the effect of †Corresponding Author: ptlsk@deu.ac.kr This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. the angles of the knee on the muscle activities of elector spinae, rectus abdominis, internal oblique and external oblique were all similar to the regular bridge exercise, but overall muscle activities were increased with heel-off when compared with the regular bridge exercise.

Perovskite solar cells (PSCs) are the most promising candidates as next-generation solar energy conversion systems. To design a highly efficient PSC, understanding electronic properties of mesoporous metal oxides is essential. Herein, we explore the effect of Nb doping of TiO2 on electronic structure and photovoltaic properties of PSCs. Light Nb doping (0.5 and 1.0 at %) increased the optical band gap slightly, but heavy doping (5.0 at %) distinctively decreased it. The relative Fermi level position of the conduction band is similar for the lightly Nb-doped TiO2 (NTO) and the undoped TiO2 whereas that of the heavy doped NTO decreased by as much as ∼0.3 eV. The lightly doped NTO-based PSCs exhibit 10 % higher efficiency than PSCs based on undoped TiO2 (from 12.2 % to 13.4 %) and 52 % higher than the PSCs utilizing heavy doped NTO (from 8.8 % to 13.4 %), which is attributed to fast electron injection/transport and preserved electron lifetime, verified by transient photocurrent decay and impedance studies.