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Purpose: This study aimed to measure toe grip strength (TGS) and identify its related factors among older adults receiving services from home-visiting caregivers. It is necessary to investigate TGS to develop fall prevention programs because the chance of falling at home increases among older adults.Methods: Data were gathered from 91 older adults enrolled in six home-visiting care centers located in C city. Six trained social workers at each center visited older adults’ homes and gathered data between March 29 and April 15, 2021.Results: There were significant differences in TGS by gender (t=2.15, p=.035), age (r=-.28, p=.006), education level (F=6.69, p

Electrical and optical characteristics of InGaN-based green micro-light-emitting diodes (µLEDs) with different active areas are investigated; results are as follows. Reverse and forward leakage currents of µLED increase as emission area is reduced owing to the non-radiative recombination process at the sidewall defects; this is more prominent in smaller µLED because of larger surface-to-volume ratio. Leakage currents of µLEDs deteriorate the carrier injection to light-emitting quantum wells, thereby degrading their external quantum efficiency. Reverse leakage current originate primarily from sidewall edges of the smallest device. Therefore, aggressive suppression of sidewall defects of µLEDs is essential for low-power and downscaled µLEDs.

Life cycle thinking analysis (LCT) was conducted on the production of vanillin via bamboo wet air oxidation compared to vanillin production from crude oil or Kraft lignin. Synthetic vanillin has been produced from crude oil and paper pulping process “waste” for nearly a century. Bamboo is quick growing, lignin rich biomass with the potential for the generation of aromatic products including vanillin. Wet air oxidation experiments were performed, using CuSO4 and Fe2O3 catalysts in alkaline environments, on raw bamboo with the purpose of determining the aromatic compound yields in order to investigate bamboo as a potential source of fine chemical products. From the LCT approach, production of vanillin from Kraft Lignin compared to crude oil has a lower environmental impact across all categories per kg produced of vanillin. Kraft lignin production of vanillin is shown to reduce smog formation and CO2 emissions from non energy sources to negligible levels while decrease acidification potential by 38 times, toxic inhalation by 18 times and toxic inhalation potential by 346 times compared to crude oil. The proposed bamboo oxidation route has the potential to have the least environmental impact with negligible impact on smog formation potential and ozone depletion potential if a green polar extractive solvent can be utilised in future while also decreasing toxicity by inhalation by a further 10 fold and ingestion by 198 fold. This work has the potential to contribute to the United Nation Sustainable Development Goal for Responsible Consumption and Production, Goal 12

Nanotechnology is an emerging field with tremendous potential and usage of medicinal plants and green preparation of nanoparticles (NPs) is one of the widely explored areas. These have been shown to be effective against different biological activities such as diabetes mellitus, cancer, antioxidant, antimicrobial, etc. The current studies focus on the green synthesis of zinc NPs (ZnO NPs) from aqueous leaf extract of Murraya koenigii (MK). The synthesized Murraya koeingii zinc oxide NPs (MK ZnO NPs) were characterized using UV-visible spectroscopy, dynamic light scattering (DLS), Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), energy-dispersive spectrum (EDS) and cyclic voltammetry (CV). The synthesized MK ZnO NPs were evaluated for their in vitro antidiabetic, antioxidant, antimicrobial, and cytotoxic activity. They demonstrated significant antidiabetic and cytotoxic activity, as well as moderate free-radical scavenging and antibacterial activity.

In this study, we aimed to better understand the mechanism for creating carrier localization centers (CLCs) in Ga0.70In0.30N/GaN quantum wells (QWs) and examine their impacts on device performance. Particularly, we focused on the incorporation of native defects into the QWs as a main cause of the mechanism behind the CLC creation. For this purpose, we prepared two GaInN-based LED samples with and without pre-trimethylindium (TMIn) flow-treated QWs. Here, the QWs were subjected to a pre-TMIn flow treatment to control the incorporation of defects/impurities in the QWs. In an effort to investigate how the pre-TMIn flow treatment affects the incorporation of native defects into the QWs, we employed steady-state photo-capacitance and photo-assisted capacitance-voltage measurements, and acquired high-resolution micro-charge-coupled device images. The experimental results showed that CLC creation in the QWs during growth is closely related to the native defects, most likely VN-related defects/complexes, since they have a strong affinity to In atoms and the nature of clustering. Moreover, the CLC creation is fatal to the performance of the yellow-red QWs since they simultaneously increase the non-radiative recombination rate, decrease the radiative recombination rate, and increase operating voltage—unlike blue QWs.

The piezoelectric field in InGaN/AlGaN-based multiple-quantum-well (MQW) near-ultraviolet light-emitting diodes (LEDs) was measured by electroreflectance and photocurrent spectroscopies. At forward and reverse biases, both electroreflectance and photocurrent spectra were studied by utilizing similar-structure samples with indium contents of ~4.5%, ~5.5%, ~6.5%, and ~7.5%. The influence of MQW and superlattice structures on the electroreflectance spectra was interactively identified. The relation between the defects and the diffusion of Mg acceptors through the defects into the MQWs was also observed and systematically confirmed through the capacitance-voltage characteristics. The effects of diffused Mg acceptors on electroreflectance spectra, depletion width, and the piezoelectric field were found. The strain relaxation caused by the defects was also systematically investigated. The calculated piezoelectric fields of these samples were in good agreement with the theoretically calculated values.

In InGaN/GaN multiple-quantum-well (MQW) light-emitting diodes (LEDs), carrier accumulation in MQWs due to the saturation of the radiative recombination rate affects the internal-quantum-efficiency (IQE) and forward-voltage ( ${V} _{\text {F}}$ ) characteristics simultaneously. In this letter, we investigate the interrelation between the IQE and ${V} _{\text {F}}$ at an operating current density, using 31 blue LEDs with MQW active layers grown under slightly different conditions. The general trend observed demonstrates that ${V} _{\text {F}}$ decreases as the IQE increases. We analyze this interrelation between the IQE and ${V} _{\text {F}}$ through separation of radiative and nonradiative current densities, and propose to use the active efficiency (AE) to quantify the performance of the active layer more precisely. We examine the two cases where only the radiative (nonradiative) current density changes and establish that the increase of the radiative current density is more desirable than the decrease of the nonradiative current density in improving the AE of the device.

As an attempt to elucidate the origin of the power-efficiency (PE) degradation at high current injection for GaInN-based light-emitting diodes, the injection current is quantitatively separated to radiative and nonradiative current components as a function of applied voltage. It is found that the conventional Shockley equation for the current-voltage curve of a Si pn diode is not adequate for the LED since the carrier transport and recombination processes are quite different from those of the Si pn diode. Hence, we propose a diode equation for an LED where the radiative and nonradiative currents are separately expressed as a function of applied voltage. By analyzing the proposed diode equation, it is concluded that the PE degradation at high injection currents is due to the increase of the junction voltage and the decrease of the internal quantum efficiency at the same time. The phenomena can be understood by the insufficient recombination rate in the active quantum wells.

Despite the wide application of organic light-emitting diodes (OLEDs), the performance of OLED devices is sometimes limited by their reliabilities. In this paper, we report the transient degradation behaviors of fluorescent blue OLEDs, where both the current and luminance initially increase under electrical stress within a short stress time. We analyze the degradation mechanism in terms of the carrier recombination and transport. From the comprehensive analyses of electrical and optical characteristics, it is suggested that the electron transport is responsible for the initial transient behavior of the device.

This study aimed to conduct a job analysis of nurse carecoordinators and to identify the frequency, importance and difficulty of each task of their job.A committee for developing a curriculum (DACUM) was formed and members of the committee defined nurse care coordinators' jobs and enumerated the duties, tasks and task elements by applying the DACUM technique. Then nurse care coordinators enrolled in the pilot project evaluated the frequency, importance and difficulty of each task.From the job descriptions of nurse care coordinators, we identified 12 duties and 42 tasks. Each task comprised 1~5 task elements. Among tasks, 'assess the patient's general health status' was carried out most frequently. Nurse care coordinators perceived that 'check vital signs' and'strengthen patient competence to promote health behaviors' were more important than all other tasks. The most difficult task was 'develop professionalism as a nurse care coordinator'.The nurse care coordinators' roles developed in this study will serve as the key guidelines for human resource management of care coordinators. Further, job specifications for nurse care coordinators need to be developed, which is necessary for designing education and training programs. We also need to integrate primary health care as an essential component in nursing education.

This work investigates the effect of current stress on InGaN/GaN multiple-quantum-well flip-chip blue micro light-emitting diodes ( μ-LEDs) with a mesa size of 30 × 30 μm2 and describes the stress-related mechanisms: defect aggregation and generation, which cause the change in optoelectronic performance of μ-LEDs. A forward-current stress is applied at 75 A/cm2 (0.7 mA) for 200 h. The device performance degrades with increasing stress time except until 25 h. During the initial 25 h of aging, the light output power and the external quantum efficiency (EQE) increase due to the improved crystal quality caused by aggregation of point defects in the active region, which are supported by the ideality factor and the S-parameter. The high-resolution emission-microscope images reveal that the generation of point defects at mesa sidewalls rather than the active region is crucial in performance degradation. We highlight, in particular, that the aging test generates sidewall point defects even though the sidewalls were properly passivated by a thick SiO2 layer. The mechanisms of defect aggregation and generation due to aging are consistently described by the ideality factor, the S-parameter, and the EQE.

This study aims to elucidate the carrier dynamics behind thermal droop in GaInN-based blue light-emitting diodes (LEDs) by separating multiple physical factors. To this end, first, we study the differential carrier lifetimes (DCLs) by measuring the impedance of a sample LED under given driving-current conditions over a very wide operating temperature range of 300 K–500 K. The measured DCLs are decoupled into radiative carrier lifetime (τR) and nonradiative carrier lifetime (τNR), via utilization of the experimental DCL data, and then very carefully investigated as a function of driving current over a wide range of operating temperatures. Next, to understand the measurement results of temperature-dependent τR and τNR characteristics, thermodynamic analysis is conducted, which enables to look deeply into the temperature-dependent behavior of the carriers. On the basis of the results, we reveal that thermal droop is originated by the complex dynamics of multiple closely interrelated physical factors instead of a single physical factor. In particular, we discuss the inherent cause of accelerated thermal droop with elevated temperature.

Drilling work on Inconel, a well-known super-heat-resistant alloy, requires a significant quantity of cutting oil to prevent heat-induced abrasion and damage to the cutting tool, caused by the strength and toughness of the alloy. This high requirement of cutting oil, however, negatively affects the processing environment, therefore, minimum-quantity lubrication (MQL), an eco-friendly cutting-oil-supply method, is attracting attention. The conventional MQL method, however, has the disadvantage that an oil-mist is produced along with high-pressure air, hence, the mist is scattered in the air, making the application of the oil to the cutting point inefficient and rendering the cooling effect to be less than that in wet processing. In this study, therefore, an eco-friendly compound, polyhedral oligomeric silsesquioxane (POSS)&mdash, a nanostructured organic&ndash, inorganic hybrid material that exhibits better adhesion to materials than conventional MQL-specific oil and is resistant to the heat generated during drilling&mdash, was developed by adding POSS to the conventional MQL-specific oil, and the effects were verified.

To assess the feasibility of a primary health care (PHC) project for people with disabilities (PwDs) in South Korea, participants' experiences and perceptions were explored using the Analysis of Determinants of Policy Impact (ADEPT) model as a guide. Three focus group interviews and three one-on-one interviews were administered, and a directed content analysis was conducted based on four determinants from the ADEPT model. The findings showed that the project goal should be specified and reviewed periodically by participants. Although they were willing to devote themselves to the project, lack of a clear job description or mutual understanding often led to participants, especially health coordinators, feeling overwhelmed with their workload. Nevertheless, the project gave PwDs an opportunity to feel that they were being cared for by their care providers, while the participants as service providers had an opportunity to provide integrated care to their patients. For the successful settlement of team-based, person-centered PHC in South Korea, the formal PHC education should include an interprofessional team approach emphasizing communication skills among the health workforce. Opinions of PwDs and their family members also need to be reflected in the content of PHC.

For accurate and reliable measurement of the internal quantum efficiency (IQE) of light-emitting diodes (LEDs), the method should be theoretically solid and experimentally simple to use without any prior assumption of physical parameters or complicated equipment. In this paper, we critically review the conventional characterization techniques for measuring the IQE of LEDs, including the methods based on temperature-dependent electroluminescence and constant AB(C) models. After reviewing the limitations of the existing IQE measurement techniques, we present the recently proposed method based on the improved AB model, called room-temperature reference-point method (RTRM). The RTRM is then applied to various LED devices to show how the IQE measurement techniques can be utilized to analyze their optoelectronic performances quantitatively.

Purpose: This study was done to develop competencies and core curriculum for gerontological nursing education in programs towards a Bachelor of Science in Nursing (BSN). Methods: From June 2015 to January 2016, competencies and core curriculum from gerontological nursing education in foreign countries were analyzed using a literature review, along with an analysis of the current gerontological nursing curriculum in Korean BSN programs. Competencies and core curriculum of undergraduate nursing education for gerontological nursing were determined through expert panel discussions in the Korean Gerontological Nursing Society. Results: Data were collected from 30 BSN programs in Seoul, Kyunggido, Kangwondo, Chungchungdo, Kyungsangdo, and Jeollado. Compared with the core curriculum for gerontological nursing recommended by the National Gerontological Nursing Association, there were deficiencies in legal/ethical issues, administrative issues, nursing research in gerontological nursing, and care and service delivery. From the data and panel discussion, 13 competencies and core curriculum including 6 contents, 32 programs, and 197 learning objectives were found to be important. Conclusion: Use of the recommended curriculum from this study can address deficiencies in baccalaureate gerontological nursing education, but it is also necessary to develop textbooks based on the recommended 13 competencies and core curriculum including 6 contents, 32 programs, and 197 learning objectives.

We present a method of measuring the internal quantum efficiency (IQE) of light-emitting diodes (LEDs) as a function of driving current at an arbitrary temperature only with experimentally measurable quantities of optical power and current. The measurement procedure starts to find an exact value of the IQE at the reference point where the injection efficiency is considered as 100% and the radiative efficiency is calculated from the infinitesimal change of the relative external quantum efficiency (EQE). Once the IQE at the reference point is exactly known, the IQE at any other point is calculated by the relative ratio of the EQE values to the reference one. We show the theoretical formalism of the proposed method and demonstrate its validity using a commercial InGaN blue LED as an example. The comparison with the IQE obtained by the conventional temperature-dependent electroluminescence is also given for various temperatures.

Cancer is a potentially fatal disease that affects people worldwide. Cancer diagnosis at a later stage is a major challenge today, and will provide essential, faster and more accurate treatment using novel diagnostic techniques. Unfortunately, traditional methods of diagnosis have not been fully helpful and most cancers are diagnosed too late. Early-stage and sensitive diagnostics for various kinds of cancer can assist patients in gaining access to the best treatment options available to combat these diseases. Development of a quick, simple, portable, and low-cost method for detecting cancer diseases is critical. As a result, biosensors have become one of the most important study fields in recent years as a potentially beneficial tool for the identification and detection of a variety of cancer cells in the early stage. Aptasensors (aptamers-based biosensors) are one of several new detection approaches that have lately showed promise in terms of sensitivity, detection or identification, of all types of cancer cells. Aptasensors can detect small and very high-selectivity cancer markers, as well as optimized time and cost savings. In this report, we discussed the current issues of aptasensors in cancer diagnostics, as well its potential future prospects.