Band gap control using electric field of photonic gel cells fabricated with block copolymer and hydrogel.

Optical and electrical characteristics of the devices using photonic gel film and hydrogel electrolyte were studied. Poly(styrene-b-2-vinylpyridine) (PS-b-P2VP) lamellar film with alternating hydrophobic block and hydrophilic polyelectrolyte block polymers (52 kg/mol-b-57 kg/mol) were prepared for the photonic gel. Poly(isobutylene-co-maleic acid) sodium salts were prepared for the hydrogel. This hydrogel fiber is common water swelling material and it owned ions for a device has conductivity. Photonic gel and hydrogel was spin coating onto Indium-tin-oxide (ITO) glass for make electric fields. The reflectance maximum wavelength of photonic crystal device shifted from 538 nm and reached to 557 nm, 585 nm and 604 nm during 30 min voltage applying time. The bandwidth variation was very limited. Loss of electrolyte was much less with hydrogel compared to the pure water. We can control color of hydrogel used photonic device by electric field with reasonable time range under moderate electric field by applying 2 V between two facing electrodes.

Fabrication and electroluminescence properties of white organic light-emitting diode with a new yellow fluorescent dopant.

A new yellow fluorescent material, (2Z)-3-[4,4"-bis(dimethylamino)-1,1':4',1"-terphenyl-2'-yl]-2-phenylacrylonitrile (BDAT-P), have been synthesized for use in organic light-emitting diodes. Opto-electronic properties of device with the structure of ITO (180 nm)/NPB (50 nm)/MADN:PFVtPh (SYB-41) 8% (17 nm)/CBP (5 nm)/CBP:Ir(pq)2acac 8% (3 nm)/CBP (5 nm)/MADN:BDAT-P 8% (3 nm)/CBP (5 nm)/MADN:SYB-41 8% (17 nm)/TPBi (40 nm)/Liq (2 nm)/Al (100 nm) was measured and revealed that BDAT-P was sufficiently applicable as a dopant of one of emitting layers in white light-emitting diodes. Maximum luminance of device was measured to be 26,950 cd/m2. Maximum luminous and quantum efficiency were observed to be 14.22 cd/A and 6.58%, respectively. The device emitted warm white light corresponding to Commission Internationale de l'Eclairage (CIExy) coordinates of (0.372, 0.424) at 11 V, (0.375,0.417) at 12 V, (0.372,0.409) at 13 V, (0.366, 0.401) at 14 V, and (0.360, 0.393) at 15 V, respectively.

Effectiveness of Peer Support Programs for Severe Mental Illness: A Systematic Review and Meta-Analysis.

(1) Background: While medication and various forms of psychotherapy are common treatments for severe mental illness, peer support programs have also proven to be effective in managing mental disorders. These programs, which involve individuals with similar experiences in navigating mental health challenges, aim to improve coping skills and foster supportive community networks. However, despite the prevalent mention of peer support programs, especially those with supervision, there has been no systematic review or meta-analysis of peer support supervision. This study aimed to systematically review and meta-analyze the forms and effectiveness of peer support programs for individuals with severe mental illnesses. (2) Methods: A literature search focusing on randomized controlled trials (RCTs) published between February 2003 and January 2024 was conducted. (3) Results: Sixteen RCTs meeting the inclusion criteria and involving a total of 4008 participants were reviewed. These studies utilized various peer support program strategies, with eight studies included in the qualitative analysis. The combined effect sizes for depressive symptoms (d = 0.12; 95% CI, -0.14, 0.37; p = 0.37), empowerment (d = 1.17; 95% CI, -0.81, 3.15; p = 0.25), quality of life (d = 0.70; 95% CI, -0.12, 1.52; p = 0.09), psychiatric symptoms (d = -0.05; 95% CI, -0.20, 0.10; p = 0.54), and self-efficacy (d = 0.20; 95% CI, 0.05, 0.36; p = 0.01) were assessed. (4) Conclusions: Our analysis emphasizes the need for further studies on peer support programs for individuals with severe mental illness, particularly those focused on self-efficacy outcomes across diverse geographic locations involving more countries and with larger scales to bolster the strength of the evidence.

High Efficiency Flat-Type GaN-Based Light-Emitting Diodes with Multiple Local Breakdown Conductive Channels.

We investigated a flat-type p*-p LED composed of a p*-electrode with a local breakdown conductive channel (LBCC) formed in the p-type electrode region by applying reverse bias. By locally connecting the p*-electrode to the n-type layer via an LBCC, a flat-type LED structure is applied that can replace the n-type electrode without a mesa-etching process. Flat-type p*-p LEDs, devoid of the mesa process, demonstrate outstanding characteristics, boasting comparable light output power to conventional mesa-type n-p LEDs at the same injection current. However, they incur higher operating voltages, attributed to the smaller size of the p* region used as the n-type electrode compared to conventional n-p LEDs. Therefore, despite having comparable external quantum efficiency stemming from similar light output, flat-type p*-p LEDs exhibit diminished wall-plug efficiency (WPE) and voltage efficiency (VE) owing to elevated operating voltages. To address this, our study aimed to mitigate the series resistance of flat-type p*-p LEDs by augmenting the number of LBCCs to enhance the contact area, thereby reducing overall resistance. This structure holds promise for elevating WPE and VE by aligning the operating voltage more closely with that of mesa-type n-p LEDs. Consequently, rectifying the issue of high operating voltages in planar p*-p LEDs enables the creation of efficient LEDs devoid of crystal defects resulting from mesa-etching processes.

Improvements in Resistive and Capacitive Switching Behaviors in Ga2O3 Memristors via High-Temperature Annealing Process.

This study investigates the effect of a high-temperature annealing process on the characteristics and performance of a memristor based on a Ag/Ga2O3/Pt structure. Through X-ray diffraction analysis, successful phase conversion from amorphous Ga2O3 to ß-Ga2O3 is confirmed, attributed to an increase in grain size and recrystallization induced by annealing. X-ray photoelectron spectroscopy analysis revealed a higher oxygen vacancy in annealed Ga2O3 thin films, which is crucial for conductive filament formation and charge transport in memristors. Films with abundant oxygen vacancies exhibit decreased set voltages and increased capacitance in a low-resistive state, enabling easy capacitance control depending on channel presence. In addition, an excellent memory device with a high on/off ratio can be implemented due to the reduction of leakage current due to recrystallization. Therefore, it is possible to manufacture a thin film suitable for a memristor by increasing the oxygen vacancy in the Ga2O3 film while improving the overall crystallinity through the annealing process. This study highlights the significance of annealing in modulating capacitance and high-resistive/low-resistive state properties of Ga2O3 memristors, contributing to optimizing device design and performance. This study underscores the significance of high-temperature annealing in improving the channel-switching characteristics of Ga2O3-based memristors, which is crucial for the development of low-power, high-efficiency memory device.

Monolithic Multicolor Emissions of InGaN-Based Hybrid Light-Emitting Diodes Using CsPbBr3 Green Quantum Dots.

To address the increasing demand for multicolor light-emitting diodes (LEDs), a monolithic multicolor LED with a simple process and high reliability is desirable. In this study, organic-inorganic hybrid LEDs with violet and green wavelengths were fabricated by depositing CsPbBr3 perovskite green quantum dots (QDs) as the light-converting material on InGaN-based violet LEDs. As the injection current was increased, the total electroluminescence (EL) intensities of the hybrid LEDs increased, whereas the light-converted green emission efficiency of the CsPbBr3 QDs decreased. The maximum green-to-violet EL spectral intensity ratio of the hybrid LEDs with CsPbBr3 QDs was achieved with the injection current of <10 mA. Moreover, the EL spectral ratio of the green-to-violet emission decreased at an injection current of 100 mA. The light-conversion intensity of the CsPbBr3 QDs decreased linearly as the junction temperature of the hybrid LEDs was increased with increasing injection current, similar to the temperature-dependent photoluminescence degradation of CsPbBr3 QDs. In addition, the junction temperature of the hybrid LED was minimized by pulse injection to suppress the thermal degradation of QDs and increase the light conversion efficiency to green emission. Therefore, the overall emission spectrum color coordinates of the hybrid LEDs exhibited a red shift from violet to blue in the low-current region and a blue shift toward violet as the green emission of the QDs was decreased above 10 mA.

Correlation between oxygen flow-controlled resistive switching and capacitance behavior in gallium oxide memristors grown via RF sputtering.

We studied on the bipolar resistive switching (RS)-dependent capacitance of Ga2O3 memristors, grown using controlled oxygen flow via a radio frequency sputtering process. The Ag/Ga2O3/Pt memristor structure was employed to investigate the capacitance changes associated with RS behavior and oxygen concentration. In the low-resistance state (LRS), capacitance increased by over 60 times compared to the high-resistance state (HRS). Furthermore, in the HRS state, increasing the oxygen flow from 0 to 0.3 sccm resulted in an 80 % decrease in capacitance, while in the LRS state, capacitance increased by 128 %. These results indicate that RS-dependent capacitance in Ga2O3 memristors is influenced by the density of oxygen vacancies. The presence of oxygen vacancies affects charge storage capacity and capacitance, with higher oxygen concentrations leading to reduced capacitance in HRS and increased capacitance in LRS. The results contribute to the understanding of the capacitance behavior in Ga2O3 memristors and highlight the significance of oxygen vacancies in their operation.

High efficiency GaN-based light emitting diode with nano-patterned ZnO surface fabricated by wet process.

The improvement of the optical output power of GaN-based light emitting diodes (LEDs) was achieved by a novel bi-layer transparent top electrode scheme. The proposed bi-layer structure is composed of a Ga-doped ZnO layer with nano-patterns obtained solely by wet etching process and an Indium Tin Oxide p-type transparent conducting electrode layer. We employed various wet-etching conditions to maximize light extraction efficiency and it was observed that the crystal morphologies of nano-patterns and optoelectronic properties are dependent on etching duration. Because of ITO under GZO layer, the current spreading was not affected even after formation of nano-patterned surface on the GZO layer by wet etching. Consequently, an enhancement of as high as 43.1% in optical output power at an injection current of 100 mA for the LED with nano-patterns wet-etched by 0.025% HCl for 30 seconds was realized without significant degradation in electrical property when compared to a reference LED.

Inkjet-printing of antimony-doped tin oxide (ATO) films for transparent conducting electrodes.

Antimony-doped Tin oxide (ATO) films have been prepared by inkjet-printing method using ATO nanoparticle inks. The electrical and optical properties of the ATO films were investigated in order to understand the effects of rapid thermal annealing (RTA) temperatures. The decrease in the sheet resistance and resistivity of the inkjet-printed ATO films was observed as the annealing temperature increased. The film annealed at 700 degrees C showed the sheet resistance of 1.7 x 10(3) Omega/sq with the film thickness of 350 nm. The optical transmittance of the films remained constant regardless of their annealing temperatures. In order to further reduce the sheet resistance of the films as well as the annealing temperature, Ag-grid was printed in between two layers of inkjet-printed ATO. With 1.5 mm Ag line spacing, the Ag-grid embedded ATO film showed the sheet resistance of 25.6 Omega/sq after RTA at 300 degrees C.

The Experiences of Psychiatric Mental Health Nurse Practitioners with Clinical Supervision in South Korea: A Grounded Theory Approach.

Clinical supervision (CS) helps improve expertise and job satisfaction in nursing staff, but its grounded research is limited. This study was conducted to derive a grounded theory based on the lived experiences of psychiatric mental health nurse practitioners (PMHNPs) in clinical supervision. Data were collected from January to April 2018 through in-depth unstructured interviews with 19 PMHMPs. Supervision of mental health nurses was necessary because of the "lack of ability to integrate theory and practice" and "difficulty working alone". The "poor supervision system" has been strengthened. The nurses used strategies such as "asking for help", "intensive training and sharing with the supervisor", "modeling of the supervisor and developing competencies", "continuing self-reflection and learning", and "participating in professional activities", according to the level of "personality characteristics", "institutional supervision policy", and "relationship with the supervisor". Consequently, the core objective of "supporting each other and becoming healthcare experts" was achieved. These findings can be used as a basis for education, practices, research, and policy development of mental health nursing. This study highlights areas for policy improvement to ensure that high-quality mental health nursing can be achieved through appropriately targeted CS.

Design and fabrication of vertical-injection GaN-based light-emitting diodes.

The fabrication process and design issues for the fabrication of vertical-injection GaN-based light-emitting diodes were investigated. The process yield was reduced according to the adhesion of reflective p-electrodes, the exposure of electroplated metal in plasma, and wet-etching induced surface textures. The chip design utilizing current blocking layer and branched n-electrode was found to significantly affect the power efficiency of LEDs.

Gate-controlled amplifiable ultraviolet AlGaN/GaN high-electron-mobility phototransistor.

Gate-controlled amplifiable ultraviolet phototransistors have been demonstrated using AlGaN/GaN high-electron-mobility transistors (HEMTs) with very thin AlGaN barriers. In the AlGaN/GaN HEMTs, the dark current between the source and drain increases with increasing thickness of the AlGaN barrier from 10 to 30 nm owing to the increase in piezoelectric polarization-induced two-dimensional electron gas (2-DEG). However, the photocurrent of the AlGaN/GaN HEMT decreases with increasing thickness of the AlGaN barrier under ultraviolet exposure conditions. It can be observed that a thicker AlGaN barrier exhibits a much higher 2-DEG than the photogenerated carriers at the interface between AlGaN and GaN. In addition, regardless of the AlGaN barrier thickness, the source-drain dark current increases as the gate bias increases from - 1.0 to + 1.0 V. However, the photocurrent of the phototransistor with the 30 nm thick AlGaN barrier was not affected by the gate bias, whereas that of the phototransistor with 10 nm thick AlGaN barrier was amplified from reduction of the gate bias. From these results, we suggest that by controlling the gate bias, a thin AlGaN barrier can amplify/attenuate the photocurrent of the AlGaN/GaN HEMT-based phototransistor.

High-performance flat-type InGaN-based light-emitting diodes with local breakdown conductive channel.

Flat-type InGaN-based light-emitting diodes (LEDs) without an n-type contact electrode were developed by using a local breakdown conductive channel (LBCC), and the effect of the In content of the InGaN quantum wells (QWs) on the local breakdown phenomenon was investigated. Electroluminescence and X-ray analyses demonstrated that the homogeneity and crystallinity of the InGaN QWs deteriorated as the In content of the InGaN QWs increased, thereby increasing the reverse leakage current and decreasing the breakdown voltage. After reverse breakdown with a reverse current of several mA, an LBCC was formed on the GaN-based LEDs. The surface size and anisotropic shape of the LBCC increased as the indium content of the InGaN QWs in the LEDs increased. Moreover, a flat-type InGaN LED without an n-type electrode was developed by using the LBCC. Notably, the resistance of the LBCC decreased with increasing indium content in the InGaN QWs, leading to lower resistance and higher light emission of the flat-type InGaN-based LEDs without an n-type contact electrode.

Breakdown-induced conductive channel for III-nitride light-emitting devices.

III-nitride semiconductor-based light-emitting diodes (LEDs) have superior physical properties, such as high thermal stability and brightness, for application to solid-state lighting sources. With the commercialization of GaN-based LEDs, improving LED reliability is important because they can be affected by electrostatic discharge, reverse leakage, and breakdown. However, research on the reverse bias characteristics of GaN-based LEDs is insufficient. We studied the reverse breakdown mechanism and demonstrated that a local breakdown can form a conductive channel in GaN-based LEDs, which can be expanded to a novel planar-type LED structure without an n-contact electrode. Furthermore, we found that this approach can be applied to AC-controllable light-emitting devices without any AC-DC converter.

Crystallographic Wet Chemical Etching of Semipolar GaN (11-22) Grown on m-Plane Sapphire Substrates.

This paper reports the etch rates and etched surface morphology of semipolar GaN using a potassium hydroxide (KOH) solution. Semipolar (11-22) GaN could be etched easily using a KOH solution and the etch rate was higher than that of Ga-polar c-plane GaN (0001). The etch rate was anisotropic and the highest etch rate was measured to be approximately 116 nm/min for the (1011) plane and 62 nm/min for the (11-20) plane GaN using a 4 M KOH solution at 100 °C, resulting in specific surface features, such as inclined trigonal cells.

Nanostructures of Indium Gallium Nitride Crystals Grown on Carbon Nanotubes.

Nanostructure (NS) InGaN crystals were grown on carbon nanotubes (CNTs) using metalorganic chemical vapor deposition. The NS-InGaN crystals, grown on a ~5-µm-long CNT/Si template, were estimated to be ~100-270 nm in size. Transmission electron microscope examinations revealed that single-crystalline InGaN NSs were formed with different crystal facets. The observed green (~500 nm) cathodoluminescence (CL) emission was consistent with the surface image of the NS-InGaN crystallites, indicating excellent optical properties of the InGaN NSs on CNTs. Moreover, the CL spectrum of InGaN NSs showed a broad emission band from 490 to 600 nm. Based on these results, we believe that InGaN NSs grown on CNTs could aid in overcoming the green gap in LED technologies.

Wet chemical etching of semipolar GaN planes to obtain brighter and cost-competitive light emitters.

Spotlight on etching: (11-22) semipolar GaN plane light-emitting diodes (LEDs) are demonstrated using a wet-etching process. A trigonal prism cell structure with a (0001) c plane and nnn{10-10} m planes is formed after KOH wet etching, and leads to a better ohmic contact and enhanced light extraction. LEDs fabricated by wet etching show excellent output performance 1.89 times higher than that of the reference LEDs.

Detection of transgene in early developmental stage by GFP monitoring enhances the efficiency of genetic transformation of pepper.

In order to establish a reliable and highly efficient method for genetic transformation of pepper, a monitoring system featuring GFP (green fluorescent protein) as a report marker was applied to Agrobacterium-mediated transformation. A callus-induced transformation (CIT) system was used to transform the GFP gene. GFP expression was observed in all tissues of T(0), T(1) and T(2) peppers, constituting the first instance in which the whole pepper plant has exhibited GFP fluorescence. A total of 38 T(0) peppers were obtained from 4,200 explants. The transformation rate ranged from 0.47 to 1.83% depending on the genotype, which was higher than that obtained by CIT without the GFP monitoring system. This technique could enhance selection power by monitoring GFP expression at the early stage of callus in vitro. The detection of GFP expression in the callus led to successful identification of the shoot that contained the transgene. Thus, this technique saved lots of time and money for conducting the genetic transformation process of pepper. In addition, a co-transformation technique was applied to the target transgene, CaCS (encoding capsaicinoid synthetase of Capsicum) along with GFP. Paprika varieties were transformed by the CaCS::GFP construct, and GFP expression in callus tissues of paprika was monitored to select the right transformant.