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High-Ni layered oxide cathodes are promising candidates for lithium-ion batteries due to their high energy density. However, their cycle stability is compromised by the poor mechanical durability of the particle microstructure. In this study, we investigate the impact of the calcination temperature on microstructural changes, including primary particle growth and pore evolution, using LiNi0.88Mn0.08Co0.04O2 (N884), with an emphasis on the critical calcination temperature for polycrystalline and single-crystal designs in high-Ni cathodes. As the calcination temperature increases, the primary particles undergo a rectangular growth pattern while the pore population decreases. Beyond a certain critical temperature (in this case, 850 °C), a sudden increase in primary particle size and a simultaneous rapid reduction in the pore population are observed. This sudden microstructure evolution leads to poor cycle retention in N884. In contrast, single-crystal particles, free of grain boundaries, synthesized at this critical temperature exhibit superior cycle retention, underscoring the significance of microstructural design over crystalline quality for achieving long-term cyclability. Our study sheds light on the interplay between calcination temperature and microstructural evolution, proposing the critical temperature as a key criterion for single-crystal synthesis.
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PURPOSE: Although interest in various forms of learning media is increasing due to the coronavirus disease 2019 (COVID-19) pandemic there is relatively little research on influencing student motivation by intervening in cognitive processing. The purpose of this study was to present the optimal form of learning materials provided to medical students. METHODS: This study provided learning materials in class at a level according to social cues (script, video [artificial intelligence (AI) voice], video [professor voice]) based on the principle of voices among the principles of personalization, voices, image, and embodiment of social cues in multimedia learning, and surveyed students' opinions. RESULTS: There was no statistically significant difference according to social clues in satisfaction and learning help, but both appeared in the order of silent videos containing the professor's voice, followed by videos containing the AI voice. CONCLUSION: This study is significant in that there is no research on the impact of student motivation on the provision of learning materials for medical school education in Korea, and we hope that it will help provide learning materials for self-directed learning of medical students in the post-COVID-19.
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COVID-19 , Estudiantes de Medicina , Humanos , Señales (Psicología) , Estudiantes de Medicina/psicología , Multimedia , Inteligencia ArtificialRESUMEN
BACKGROUND: Poly-L-lactic acid (PLLA), a synthetic, biocompatible, and biodegradable polymer, has been safely used in several clinical applications. Recently, PLLA has been widely used in the field of dermatology to treat wrinkles in aging skin. Reportedly, PLLA directly acts on dermal fibroblasts causing a significant increase in the expression of type I collagen. However, little is known about the effect of PLLA on adipocytes. OBJECTIVE: This study aimed to analyze the effect of PLLA on adipocytes and examine its potential in treating deep wrinkles engendered by the loss of subcutaneous fat because of aging and photoaging. METHODS: To elucidate the effect of PLLA on skin photoaging, cultured 3T3-L1 adipocytes were irradiated with ultraviolet B (UVB) rays. Oil red O staining was used to detect lipid accumulation in the adipocytes. Real-time quantitative polymerase chain reaction and Western blotting were performed to detect types IV and VI collagen mRNA and protein levels, respectively, under different conditions. RESULTS: The differentiation of 3T3-L1 cells enhanced adipogenesis and the expression of types IV and VI collagens, both of which were inhibited by UVB irradiation. Following this irradiation, PLLA stimulated adipogenesis and the expression of types IV and VI collagens. CONCLUSION: PLLA may provide the beneficial effect on adipocytes from the aspect of adipogenesis and collagen expression in the subcutaneous adipose tissues.
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PURPOSE: This study was conducted to examine the results of designing and implementing a teaching program for medical education as the elective course for 4th-year students of medical course. METHODS: In order to design the teaching program for medical education as an elective course, we conducted literature review, five medical education experts were interviewed, and the literature required in the design process was reviewed. A developing teaching program was implemented as an elective course in a medical school of Korea, and 4th-year students of medical course participated in the program. RESULTS: In the elective course, the medical education program process competencies were derived into three categories: theoretical educational knowledge, teaching competency, and research competency for education. Moreover, instructional materials were developed to help students achieve these competencies. And project-based learning strategy was selected and implemented for 4th-year students in medical course, and positive satisfaction was confirmed. CONCLUSION: As a study designed and implemented in a medical education program in a medical school in Korea, it is expected to be helpful when introducing medical education to undergraduate students or developing a medical education program to strengthen the teaching capacity of residents.
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Educación de Pregrado en Medicina , Educación Médica , Estudiantes de Medicina , Humanos , Curriculum , Estudiantes , República de Corea , EnseñanzaRESUMEN
Porokeratosis ptychotropica is an uncommon form of porokeratosis, which was initially described in 1995. It is clinically characterized by symmetrical reddish to brown-colored hyperkeratotic, verrucous, or psoriasiform plaques on the perianal and gluteal regions. The lesions tend to integrate and expand centrally, with small peripheral satellite lesions. Early skin biopsy and appropriate diagnosis are essential because malignant change occurs in 7.5% of porokeratotic lesions. Conventional treatment options include topical steroid, retinoid, imiquimod, 5-fluorouracil, isotretinoin, excimer laser, photodynamic therapy, intralesional steroid or bleomycin injection, cryotherapy, carbon dioxide (CO2) laser, and dermatome and excision, but none seem to achieve complete clearance. A 68-year-old woman presented with diffuse hyperkeratotic scaly lichenoid plaques on the buttocks that had persisted for several years. A skin biopsy of the buttocks revealed multiple cornoid lamellae and intense hyperkeratosis. There were some dyskeratotic cells beneath the cornoid lamellae and the granular layer was absent. Porokeratosis ptychotropica was diagnosed based on the characteristic clinical appearance and typical histopathological manifestations. She was treated with a CO2 laser in one session and topical application of urea and imiquimod cream for 1 month. The lesions slightly improved at the 1-month follow-up. We herein present a rare case of porokeratosis ptychotropica.
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Hypoxemia and multiple organ dysfunction are significant contributors to mortality in patients with pediatric acute respiratory distress syndrome (PARDS). P50, the oxygen tension at which hemoglobin is 50% saturated, is a measure of hemoglobin-oxygen affinity, and its alteration might have implications for tissue hypoxia and organ dysfunction. The purpose of this single-center, retrospective study was to evaluate P50 levels in PARDS and to determine the association between P50 and clinical outcomes. The study included 212 children diagnosed with PARDS according to the Pediatric Acute Lung Injury Consensus Conference definition who required invasive mechanical ventilation and had arterial blood gas results of hemoglobin oxygen saturation < 97% at the time of diagnosis. P50 levels were calculated using Doyle's method, and organ dysfunction was assessed using the Pediatric Logistic Organ Dysfunction-2 score. Most patients exhibited more than one dysfunctional extrapulmonary organ at PARDS onset. P50 increased with increasing PARDS severity (mild (26.6 [24.9-29.6]), moderate (26.8 [25.0-29.5]), and severe PARDS (29.1 [26.1-32.4] mmHg; P = 0.025). Moreover, P50 demonstrated a significant positive association with extrapulmonary organ dysfunction score (ß = 0.158, P = 0.007) and risk of mortality (adjusted hazard ratio, 1.056; 95% confidence interval, 1.015-1.098; P = 0.007), irrespective of initial PARDS severity. The relationship between P50 and mortality was largely mediated by extrapulmonary organ dysfunction. A high P50 value at the time of PARDS diagnosis may be associated with mortality via dysfunctional extrapulmonary organs. Future studies should consider P50 as a potential candidate index for risk stratification of PARDS patients.
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Insuficiencia Multiorgánica , Síndrome de Dificultad Respiratoria , Niño , Humanos , Hipoxia , Insuficiencia Multiorgánica/etiología , Oxígeno , Respiración Artificial/métodos , Síndrome de Dificultad Respiratoria/terapia , Estudios RetrospectivosRESUMEN
OBJECTIVE: To summarize proceedings of a workshop convened to discuss the current state of science in the disease of osteoarthritis (OA), identify the knowledge gaps, and examine the developmental and regulatory challenges in bringing these products to market. DESIGN: Summary of the one-day workshop held virtually on June 22nd, 2021. RESULTS: Speakers selected by the Planning Committee presented data on the current approach to assessment of OA therapies, biomarkers in OA drug development, and the assessment of disease progression and long-term benefit. CONCLUSIONS: Demonstrated by numerous failed clinical trials, OA is a challenging disease for which to develop therapeutics. The challenge is magnified by the slow time of onset of disease and the need for clinical trials of long duration and/or large sample size to demonstrate the effect of an intervention. The OA science community, including academia, pharmaceutical companies, regulatory agencies, and patient communities, must continue to develop and test better clinical endpoints that meaningfully reflect disease modification related to long-term patient benefit.
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Osteoartritis , Biomarcadores , Progresión de la Enfermedad , Desarrollo de Medicamentos , Humanos , Osteoartritis/tratamiento farmacológicoRESUMEN
Background and Objective: In 2020, during the coronavirus disease (COVID-19) pandemic, medical students were placed in a learning environment that exposed them to unsafe clinical settings. In this study, using a phenomenological approach, we analyze the experiences of fourth-year students in the Daegu area of South Korea, a region that experienced a high concentration of COVID-19 infections. Methods: The essays of 80 students from four medical schools who agreed to participate in the study were utilized in the final data analysis. The data were analyzed using the proposed phenomenological analysis. Results: Forty-seven condensed meaning units, twelve subthemes, and three essential themes were identified. The main theme includes the following: 1) confusion and stress due to sudden changes in the learning situation 2) learned the medical professionalism of physicians 3) reflection and internal change regarding what it means to be a physician. Conclusions: The COVID-19 pandemic had a significant impact on students who participated in clinical clerkships. This study can provide baseline data for planning educational strategies and establishing a support system for students in response to the changes that they may experience in the event of the reoccurrence of a novel infectious disease in the future.
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OBJECTIVE: There is an unmet need for therapies that target the underlying pathophysiology of osteoarthritis (OA). However, defining appropriate measures for clinical trials of such therapies is challenging. Our objective was to propose concept clinical end points that directly capture clinical benefit in this setting and evaluate the feasibility of their use. METHODS: This analysis used the multicenter, longitudinal, observational Osteoarthritis Initiative (OAI) database. OAI participants primarily had knee OA, with follow-up of up to 9 years and assessments of joints, surgical interventions, performance outcomes, and patient-reported outcomes. We examined this data set to identify existing outcome measures of direct clinical benefit. We evaluated the feasibility of conducting trials using these candidate end points by estimating incidence rates and resulting required sample sizes and study durations in time-to-event analyses. RESULTS: We identified candidate end points based on total knee replacement (TKR) and composite end points defined by TKR and conservative thresholds of patient-reported outcomes of pain and function. Using time to TKR as an end point, a study with an average follow-up time of 3 years requires approximately 3,000 to 18,000 subjects, depending on effect size. Alternatively, for a composite end point, such as "time to TKR or severe pain or severely impaired functioning," the required sample sizes ranged from approximately 2,000 to 11,000 for a 3-year study. CONCLUSION: The proposed concept end points can reliably and feasibly evaluate the effectiveness of therapies for this unmet need. In particular, the composite end point approach can substantially reduce sample sizes (up to approximately 40%) compared to the use of TKR alone.
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Artroplastia de Reemplazo de Rodilla , Osteoartritis de la Rodilla , Humanos , Incidencia , Osteoartritis de la Rodilla/diagnóstico , Osteoartritis de la Rodilla/cirugía , Dolor/cirugía , Dimensión del DolorRESUMEN
BACKGROUND: A foodborne pathogen, Vibrio vulnificus, encounters normal microflora inhabiting the gut environments prior to causing fatal septicemia or gastroenteritis and should overcome the barriers derived from the gut commensals for successful infection. Its interactions with gut commensals during the infection process, however, have not yet been understood. In the present study, the effect of V. vulnificus on the community structures of gut microbiota in mice was examined. RESULTS: Analyses of microbiota in the fecal samples of mice that died due to V. vulnificus infection revealed the decreased abundance of bacteria belonged to Bacteroidetes, notably, the species Bacteroides vulgatus. In vitro coculturing of the two bacterial species resulted in the decreased survival of B. vulgatus. The antagonistic effect of V. vulnificus against B. vulgatus was found to be mediated by cyclo-Phe-Pro (cFP), one of the major compounds secreted by V. vulnificus. cFP-treated B. vulgatus showed collapsed cellular morphology with an undulated cell surface, enlarged periplasmic space, and lysed membranes, suggesting the occurrence of membrane disruption. The degree of membrane disruption caused by cFP was dependent upon the cellular levels of ObgE in B. vulgatus. Recombinant ObgE exhibited a high affinity to cFP at a 1:1 ratio. When mice were orally injected with cFP, their feces contained significantly reduced B. vulgatus levels, and their susceptibility to V. vulnificus infection was considerably increased. CONCLUSIONS: This study demonstrates that V. vulnificus-derived cFP modulates the abundance of the predominant species among gut commensals, which made V. vulnificus increase its pathogenicity in the hosts. Video abstract.
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Microbioma Gastrointestinal , Vibrio vulnificus , Animales , Bacteroides , Membrana Celular , RatonesRESUMEN
This paper is submitted to accompany the article "Analyses of three-dimensional weather radar data from volcanic eruption clouds" [1]; it describes three-dimensional (3D) visualizations of the Sakurajima volcanic eruption clouds and the weather radar data used for analyses, as well as their availability and downloading procedures. The radar data were acquired by an operational X-band weather radar located approximately 11 km south of the Showa vent of Sakurajima in Kagoshima, Japan. The original raw radar data are available from the "XRAIN Precipitation Original Data search and Download System", which is hosted on the website "Data Integration and Analysis System (DIAS)". Animated images of the radar data shown here, which provide a visual explanation of the temporal evolution and the inner structure of volcanic eruption clouds, were created using the program "Analysis Tools of Three-dimensional Weather Radar Data (AN3D)". The detailed methods of ANT3D are provided in the co-submitted article "Construction of three-dimensional weather radar data from volcanic eruption clouds" [2].
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In the 21st-century postmodernism era, which represents diversity and relativity, one of the most essential elements in the field of education is to strengthen individual human values. Accordingly, we must focus on developing capacity in order to adapt to change. It is clear that the medical field maximizes the need for new judgments to solve life-related problems constantly, and this problem-solving capacity is an essential skill for a physician. Problem-solving capacity can be achieved simultaneously with creativity to apply them in an appropriate manner based on standardized expertise and well-trained skills. Creativity is also a key element that medical education is currently pursuing. Many studies on creativity have resulted in confusion and misunderstandings on the concept of creativity due to similar terms and varied definitions, such as creation, innovation, etc. In this study, we attempt to identify the importance of creativity in medical education by comparing and organizing concepts related to creative capacity.
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The data presented in this article are related to the research article entitled "Three-dimensional analysis of the initial stage of convective precipitation using an operational X-band polarimetric radar network" [1]. The data presented were obtained using a three-dimensional constant-altitude plan-position-indicator (3D CAPPI), which was generated by a new method proposed by [1]. The data used to create the 3D CAPPI were derived from two X-band polarimetric radar installations in the Kanto region of Japan, Ebina (139.39°E, 35.40°N), and Shin-yokohama (139.60°E, 35.51°N). These data are superior to operational radar data in terms of their temporal and spatial resolution. These high resolution data can indicate a rapidly developing storm, such as localized precipitation. It is particularly important to understand the early stages of storms in terms of numerical and short-term models. These data show the time of appearance, life cycle, and evolution of each cell that constitutes a storm in three-dimensional detail.
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Resting state functional connectomes are massive and complex. It is an open question, however, whether connectomes differ across individuals in a correspondingly massive number of ways, or whether most differences take a small number of characteristic forms. We systematically investigated this question and found clear evidence of low-rank structure in which a modest number of connectomic components, around 50-150, account for a sizable portion of inter-individual connectomic variation. This number was convergently arrived at with multiple methods including estimation of intrinsic dimensionality and assessment of reconstruction of out-of-sample data. In addition, we show that these connectomic components enable prediction of a broad array of neurocognitive and clinical symptom variables at levels comparable to a leading method that is trained on the whole connectome. Qualitative observation reveals that these connectomic components exhibit extensive community structure reflecting interrelationships between intrinsic connectivity networks. We provide quantitative validation of this observation using novel stochastic block model-based methods. We propose that these connectivity components form an effective basis set for quantifying and interpreting inter-individual connectomic differences, and for predicting behavioral/clinical phenotypes.
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Encéfalo/fisiología , Conectoma , Descanso , Encéfalo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Modelos Neurológicos , FenotipoRESUMEN
Owing to its high sensitivity and high selectivity along with rapid response time, plasmonic detection has gained considerable interest in a wide variety of sensing applications. To improve the fieldwork applicability and reliability of plasmonic detection, the integration of plasmonic nanoparticles into optical devices is desirable. Herein, we propose an integrated label-free detection platform comprising a plasmonic cavity that allows sensitive molecular detection via either surface-enhanced Raman scattering (SERS) or plasmon resonance energy transfer (PRET). A small droplet of metal ion solution spontaneously produces a plasmonic cavity on the surface of uncured poly(dimethylsiloxane) (PDMS), and as PDMS is cured, the metal ions are reduced to form a plasmonic antennae array on the cavity surface. Unique spherical feature and the integrated metallic nanoparticles of the cavity provide excellent optical functions to focus the incident light in the cavity and to rescatter the light absorbed by the nanoparticles. The optical properties of the plasmonic cavity for SERS or PRET are optimized by controlling the composition, size, and density of the metal nanoparticles. By using the cavity, we accomplish both 1000-fold sensitive detection and real-time monitoring of reactive oxygen species secreted by live cells via PRET. In addition, we achieve sensitive detection of trace amounts of toxic environmental molecules such as 5-chloro-2-methyl-4-isothiazolin-3-one/2-methyl-4-isothiazol-3-one (CMIT/MIT) and bisphenol A, as well as several small biomolecules such as glucose, adenine, and tryptophan, via SERS.
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In this study, we investigated an energy harvesting effect of tensile stress using piezoelectric polymers and flexible electrodes. A chemical-vapor-deposition grown graphene film was transferred onto both sides of the PVDF and P(VDF-TrFE) films simultaneously by means of a conventional wet chemical method. Output voltage induced by sound waves was measured and analyzed when a mechanical tension was applied to the device. Another energy harvester was made with a metallic electrode, where Al and Ag were deposited by using an electron-beam evaporator. When acoustic vibrations (105 dB) were applied to the graphene/PVDF/graphene device, an induced voltage of 7.6 Vpp was measured with a tensile stress of 1.75 MPa, and this was increased up to 9.1 Vpp with a stress of 2.18 MPa for the metal/P(VDF-TrFE)/metal device. The 9 metal/PVDF/metal layers were stacked as an energy harvester, and tension was applied by using springs. Also, we fabricated a full-wave rectifying circuit to store the electrical energy in a 100 µF capacitor, and external vibration generated the electrical charges. As a result, the stored voltage at the capacitor, obtained from the harvester via a bridge diode rectifier, was saturated to ~7.04 V after 180 s charging time.
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Reactive oxygen species (ROS) are strong oxidants, and have attracted considerable attention in both biological and environmental fields. Although various methods for ROS detection, including optical and electrochemical techniques, have been developed, they still face challenging issues in terms of poor sensitivity, reproducibility, stability, and in vivo applicability. Here, we present a sensitive and selective optical sensor for ROS detection, based on single plasmonic nanoprobes and redox-active cytochrome c (Cyt c)-mediated plasmon resonance energy transfer. By measuring the spectral changes of plasmonic nanoprobes, derived from the unique molecular absorption of Cyt c in accordance with the redox state, calibration curves for H2O2, a representative ROS, in various media were obtained over a wide concentration range from 100 mM to 1 nM. Limit of detection and limit of quantification in accordance with the used medium were determined from 8.3 to 12.8 nM and from 27.6 to 42.7 nM, respectively. Selectivity coefficients for major interfering solutes were much lower than 0.1 indicating a good selectivity for ROS. From the dynamic spectral changes, we sensitively monitored ROS generated in Caenorhabditis elegans (C. elegans) exposed to graphene oxide. Based on the calibration curves, we also determined ROS levels in various aquatic environments, such as river streams and a small pond, as a way of environmental monitoring. We believe that our approach could provide an avenue for achieving dynamic and sensitive monitoring of ROS in toxicological, biological, and environmental fields in the future.
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Monitoreo del Ambiente , Nanopartículas , Especies Reactivas de Oxígeno/análisis , Animales , Caenorhabditis elegans/metabolismo , Peróxido de Hidrógeno , Estanques , Reproducibilidad de los Resultados , RíosRESUMEN
Herein, we report a novel method for H2O2 detection based on a single plasmonic nanoprobe via cytochrome c (Cyt c)-mediated plasmon resonance energy transfer (PRET). Dynamic spectral changes were observed in the fingerprint quenching dip of a single plasmonic nanoprobe in response to changes in the redox state of Cyt c, induced by H2O2. Based on the changes in the spectral profile of the single plasmonic nanoprobe, H2O2 was successfully detected in a wide concentration range from 100 mM to 10 nM, including physiologically relevant micromolar and nanomolar concentrations.
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Citocromos c/química , Transferencia Resonante de Energía de Fluorescencia , Oro/química , Peróxido de Hidrógeno/análisis , Nanopartículas del Metal/química , Citocromos c/metabolismo , Peróxido de Hidrógeno/metabolismo , Oxidación-ReducciónRESUMEN
OBJECTIVE: To compare the diagnostic performance of contrast-enhanced (CE) magnetic resonance imaging (MRI) and non-CE MRI for adhesive capsulitis (AC). METHODS: CE MRI of 50 AC and 53 non-AC patients were reviewed by two radiologists independently. RESULTS: Axillary capsular thickening and T2 hyperintensity (sensitivity=92-94%; specificity=53-64%) and enhancement of the axillary capsule and rotator interval (sensitivity=92-98%; specificity=38-64%) were helpful in diagnosing AC. Interobserver reliability was highest with axillary joint capsule enhancement (κ=0.92). CONCLUSION: Non-CE and CE MRI are helpful in confirming the clinical diagnosis of AC. CE-MRI may improve assessment of the rotator interval and diagnostic confidence in patients with AC.
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Bursitis/diagnóstico , Imagen por Resonancia Magnética/métodos , Articulación del Hombro/patología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto JovenRESUMEN
BACKGROUND: The aim of this study was to evaluate the effect of an Assertive Community Treatment (ACT) program on psychiatric symptoms, global functioning, life satisfaction, and recovery-promoting relationships among individuals with mental illness. METHODS: Participants were patients at the Suwon Mental Health Center. Thirty-two patients were part of the ACT program and 32 patients matched for age, sex, and mental illness were in a standard case-management program and served as a control group. Follow-up with patients occurred every 3 months during the 15 months after a baseline interview. Participants completed the Brief Psychiatric Rating Scale (BPRS), Global Assessment of Functioning (GAF) Scale, Life Satisfaction Scale, and Recovery-Promoting Relationship Scale (RPRS). RESULTS: No significant differences were noted in the sociodemographic characteristics of the ACT and the case-management group. According to the BPRS, the ACT group showed a significant reduction in symptom severity, but the ACT program was not significantly more effective at reducing psychiatric symptoms from baseline to the 15-month follow-up compared to the case-management approach. The ACT group showed more significant improvement than the control group in terms of the GAF Scale. Both groups showed no significant differences in the change of life satisfaction and in the change of recovery-promoting relationships. We observed a significant increase in recovery-promoting relationships in the control group, but the degree of change of recovery-promoting relationships through time flow between groups was not significantly different. DISCUSSION: In this study, we observed that ACT was significantly better at improving the GAF than case management and that participation in ACT was associated with a significant decrease in BPRS scores. However, ACT did not demonstrate an absolute superiority over the standard case-management approach in terms of the BPRS and the measures of life satisfaction and recovery-promoting relationships. CONCLUSIONS: ACT may have some advantages over a standard case management approach.