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1.
Small ; : e2400692, 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38651492

ABSTRACT

Aqueous rechargeable zinc-ion batteries (ARZIBs) are considered as an emerging energy storage technology owing to their low cost, inherent safety, and reasonable energy density. However, significant challenges associated with electrodes, and aqueous electrolytes restrict their rapid development. Herein, ethylene glycol-choline chloride (Eg-ChCl) based hydrated deep-eutectic electrolytes (HDEEs) are proposed for RZIBs. Also, a novel V10O24·nH2O@rGO composite is prepared and investigated in combination with HDEEs. The formulated HDEEs, particularly the composition of 1 ml of EG, 0.5 g of ChCl, 4 ml of H2O, and 2 M ZnTFS (1-0.5-4-2 HDEE), not only exhibit the lowest viscosity, highest Zn2+ conductivity (20.38 mS cm-1), and the highest zinc (Zn) transference number (t+ = 0.937), but also provide a wide electrochemical stability window (>3.2 V vs ZnǁZn2+) and enabledendrite-free Zn stripping/plating cycling over 1000 hours. The resulting ZnǁV10O24·nH2O@rGO cell with 1-0.5-4-2 HDEE manifests high reversible capacity of ≈365 mAh g-1 at 0.1 A g-1, high rate-performance (delivered ≈365/223 mAh g-1 at 0.1/10 mA g-1) and enhanced cycling performance (≈63.10% capacity retention in the 4000th cycle at 10 A g-1). Furthermore, 1-0.5-4-2 HDEE support feasible Zn-ion storage performance across a wide temperature range (0-80 °C) FInally, a ZnǁV10O24·nH2O@rGO pouch-cell prototype fabricated with 1-0.5-4-2 HDEE demonstrates good flexibility, safety, and durability.

2.
Sensors (Basel) ; 23(10)2023 May 10.
Article in English | MEDLINE | ID: mdl-37430539

ABSTRACT

With the development of artificial intelligence technology, systems that can actively adapt to their surroundings and cooperate with other systems have become increasingly important. One of the most important factors to consider during the process of cooperation among systems is trust. Trust is a social concept that assumes that cooperation with an object will produce positive results in the direction we intend. Our objectives are to propose a method for defining trust during the requirements engineering phase in the process of developing self-adaptive systems and to define the trust evidence models required to evaluate the defined trust at runtime. To achieve this objective, we propose in this study a provenance-based trust-aware requirement engineering framework for self-adaptive systems. The framework helps system engineers derive the user's requirements as a trust-aware goal model through analysis of the trust concept in the requirements engineering process. We also propose a provenance-based trust evidence model to evaluate trust and provide a method for defining this model for the target domain. Through the proposed framework, a system engineer can treat trust as a factor emerging from the requirements engineering phase for the self-adaptive system and understand the factors affecting trust using the standardized format.

3.
Adv Sci (Weinh) ; 10(7): e2205690, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36638252

ABSTRACT

Crystal structures determine material properties, suggesting that crystal phase transformations have the potential for application in a variety of systems and devices. Phase transitions are more likely to occur in smaller crystals; however, in quantum-sized semiconductor nanocrystals, the microscopic mechanisms by which phase transitions occur are not well understood. Herein, the phase transformation of 2D CdSe quantum nanosheets caused by off-stoichiometry is revealed, and the progress of the transformation is directly observed by in situ transmission electron microscopy. The initial hexagonal wurtzite-CdSe nanosheets with atomically uniform thickness are transformed into cubic zinc blende-CdSe nanosheets. A combined experimental and theoretical study reveals that electron-beam irradiation can change the stoichiometry of the nanosheets, thereby triggering phase transformation. The loss of Se atoms induces the reconstruction of surface atoms, driving the transformation from wurtzite-CdSe(11 2 ¯ $\bar{2}$ 0) to zinc blende-CdSe(001) 2D nanocrystals. Furthermore, during the phase transformation, unconventional dynamic phenomena occur, including domain separation. This study contributes to the fundamental understanding of the phase transformations in 2D quantum-sized semiconductor nanocrystals.

4.
Article in English | MEDLINE | ID: mdl-36498391

ABSTRACT

This study was to investigate the effects of 13 weeks of long-distance cycling on biomarkers of joint cartilage, muscle damage and inflammation. All subjects in this study were seven participants of the "One Korea New-Eurasia Peace Cycle Expedition", in which they rode cycles from Berlin, Germany to Seoul, Korea for thirteen weeks. The total course of the expedition was divided into three sub-courses: course 1 (from Berlin to Moscow), course 2 (from Moscow to Ulaanbaatar) and course 3 (from Ulaanbaatar to Seoul). All the selected participants rode 87.4 km/day (course 1), 70.4 km/day (course 2) and 57.6 km/day (course 3) on average, respectively. We collected their blood samples before the expedition in Seoul (S1), after course 1 in Moscow (M), after course 2 in Ulaanbaatar (U) and after the expedition in Seoul (S2), to analyze biomarkers of joint cartilage damage (Cartilage Oligomeric Matrix Protein; COMP), muscle damage (Creatine Phosphokinase; CPK, Lactate Dehydrogenase; LDH, Myoglobin), inflammation (Interleukin-6; IL-6, Interleukin-1ß; IL-1ß, Tumor Necrosis Factor-α; TNF-α, C-Reactive Protein; CRP) and stress hormone (Cortisol). According to this result, COMP (S1; 188.37 ± 46.68 ng/mL) showed a significant increase after the expedition course 1 (M; 246.69 ± 51.69 ng/mL, p = 0.012) and course 2 (U; 237.09 ± 62.57 ng/mL, p = 0.047), and recovered to the stable state after expedition course 3 (S2; 218.46 ± 34.78. p = 0.047). Biomarkers of muscle damage (CPK, LDH and Myoglobin) and inflammation (IL-6, IL-1ß, TNF-α and CRP) were not significantly changed in all courses, but CRP (S1; 1.07 ± 0.76 ng/mL) showed a tendency to decrease after the expedition course 1 (M; 0.3 ± 0.1 mg/mL, p = 0.044). Lastly, the Cortisol level significantly increased in all courses (per p < 0.05), but the Cortisol level after expedition course 3 (S2; 21.00 ± 3.65 mg/mL) was lower than that of after the expedition course 1 (M; 24.23 ± 2.47 mg/mL, p = 0.028). In summary, it seems that repetitive and continuous 50−90 km/day of cycling can increase joint cartilage damage risk and stress hormone temporarily. However, this result suggests that the appropriate intensity of cycling for thirteen weeks does not increase physical damage, and rather enhances the human body to adapt to exercise training.


Subject(s)
Bicycling , Cartilage, Articular , Muscles , Humans , Biomarkers , Cartilage, Articular/injuries , Cartilage, Articular/metabolism , Hormones , Inflammation , Interleukin-6 , Muscles/injuries , Muscles/metabolism , Tumor Necrosis Factor-alpha/metabolism , Bicycling/physiology
5.
J Phys Ther Sci ; 27(7): 2373-6, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26311985

ABSTRACT

[Purpose] This study investigated the effect of horseback riding exercise on the background electroencephalograms of elderly people who performed horseback riding for 8 weeks. [Subjects] Twenty elderly people were divided into the horseback riding exercise and control group (n = 10 each). [Methods] The exercise was performed for 15 minutes, 3 times per week for 8 weeks. Electroencephalograms were analyzed. Post-exercise evaluation was performed after 8 weeks. [Results] After the horseback riding exercise, the relative slower alpha power index was active in the T3 and P4 domains but suppressed in the Fp1, Fp2, F3, F4, T4, and P3 domains. Moreover, the relative faster alpha power index was active in all domains of the horseback riding exercise group but was suppressed in all domains of the control group. There was a significant difference between groups in the F3 domain. [Conclusion] The alpha power index increased significantly after horseback riding exercise, suggesting the exercise improved background electroencephalogram.

6.
J Phys Ther Sci ; 27(3): 581-3, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25931685

ABSTRACT

[Purpose] The purpose of this study was to determine how an exercise program focusing on muscular strength could aid firefighters with chronic lower back pain. [Subjects] The research subjects were randomly assigned to two groups, the experimental group (n=8) and the control (n=8). [Methods] The experimental group performed two types of exercise programs four times per week for 8 weeks under supervision. Tests were performed before and after the 8 weeks of exercise in accordance with the Korea Occupational Safety and Health Agency's program. [Results] At the end of the 8 weeks of the rehabilitation program, abdominal muscular strength were significantly increased in the experimental group, and this indicates that the exercise therapy was effective for improvement of muscular strength. [Conclusion] We found that exercise therapy is an effective intervention that can reduce the pain of patients with chronic lower back pain. The firefighters with chronic lower back pain who participated in this study exhibited enhanced lower back muscular strength and obtained some additional benefits. They need regular exercise.

7.
J Phys Ther Sci ; 27(4): 989-92, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25995539

ABSTRACT

[Purpose] The aim of this study was to investigate the effect of an exercise intervention on the balance ability and muscle function of elderly women. [Subjects] The subjects were randomly divided into a control group (n=10) and an exercise group (n=10). [Methods] The subjects participated in an elastic band exercise program lasting for 8 weeks, exercising for 40 minutes, four days a week with resting terms of 60 sec. Subjects used a band corresponding to 60% of the strength of the color band with which repetitive exercise was possible up to twelve times. The subjects performed elastic band exercises, with variations to the number of band exercises according to the improvement of their physical fitness levels. When fifteen repetitive elastic band exercises could be performed with no damage of the body, we changed the band for one which was one level up from the former one and subjects used the same band for the upper body and lower body. [Results] Leg muscular strength measured as sit-stand repetitions in 30 s significantly increased in the exercise group after the intervention compared to before the intervention. Leg muscular endurance measured as the number of knee ups in 2 minutes significantly increased in the exercise group after the intervention compared to before the intervention. Balance measured by one-leg standing time with the eyes open significantly improved in the exercise group after the intervention compared to before the intervention. [Conclusion] Balance ability and muscle function significantly improved in the exercise group and showing that the intervention is effective at improving balance, muscle strength, and muscle endurance of elderly women.

8.
J Phys Ther Sci ; 26(11): 1675-7, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25435675

ABSTRACT

[Purpose] The aim of this study was to examine the effects of exercise therapy on blood lipids of obese women. [Subjects] The subjects were 24 clinically obese women. [Methods] The subjects were divided into an exercise group (n=12), and a control group (n=12). The exercise group performed exercise for 10 weeks with diet restriction. We investigated how this type of exercise influenced blood lipids. Blood was taken before and after the intervention. The collected blood was centrifuged at 3,000 rpm for 10 minutes; and plasma was preserved at -73 °C. For hemanalysis, a medical laboratory was asked to analyze total cholesterol and triglyceride. The exercise was performed 5 times per week, and an exercise was performed every two days, and exercise program was composed of warm up, main exercise and cool down. [Results] There were significant differences between the two groups in blood lipid levels after the intervention. The differences between the two groups in TC and TG were significant. [Conclusion] TC and TG significantly inproved in the experimental group showing that the exercise was effective at improveing blood lipid levels.

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