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Other than the fully synchronized state, a twisted state can also be an equilibrium solution in the Kuramoto model and its variations. In the present work, we explore the stability of the twisted state in Kuramoto oscillators put on a rim of a planar circle in the two-dimensional space in the presence of power-law decaying interaction strength (â¼r^{-α} with the distance r) and time delays due to a finite speed of information transfer. For example, our model can phenomenologically mimic a large sports stadium where many people try to sing or clap their hands in unison; the sound intensity decays with the distance and there can exist a time delay proportional to the distance due to the finiteness of sound speed. We first consider the case without the time delay effect and numerically find that stable twisted states emerge when the exponent α exceeds a critical value of α_{c}≈2. In other words, for α<α_{c}, the fully synchronized state, not the twisted state, is the only stable fixed point of the dynamics. In our analytic approach, we also derive an equation for α_{c} and discuss its solutions. In the presence of time delay, we find that it is possible that the synchronized state becomes unstable while twisted states are stable.
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PURPOSE: To determine the genomic feature of novel spotted fever-causing Rickettsia koreansis strain CNH17-7, which is different from R. japonica that is a causative agent for Japanese spotted fever (JSF), and to perform its comparative genomic analysis. METHODS: Whole genome sequencing (WGS) was performed on R. koreansis strain CNH17-7 by using the Illumina Miseq system. After WGS, assembly and annotation were done by SPAdes. Then, its genomic features were compared with 19 different Rickettsia species. Based on the average nucleotide identity (ANI) value, an unweighted pair group method with an arithmetic mean (UPGMA) dendrogram was generated. Following the dendrogram analysis, pan-and core-genome analysis was performed. Then additional comparative analyses with two genetically closest Rickettsia species were conducted based on gene repertoire. RESULTS: R. koreansis strain CNH17-7 has a chromosome consisting of 1,392,633 bp with GC content of 32.4%. The ANI-derived UPGMA showed that R. koreansis strain CNH17-7 is genetically close to R. japonica YH and R. heilongjiangensis 054 but is distinctively differentiated. The ANI value of R. koreansis strain CNH17-7 to R. japonica YH and R. heilongjiangensis 054 are 98.14% and 98.04% respectively, indicating R. koreansis strain CNH17-7 is sufficient to be classified as a new species. Other than ANI, R. koreansis strain CNH17-7 also contains novel CDS and its COG functional category proportion which is distinct compared to R. japonica YH and R. heilongjiangensis 054. CONCLUSION: We have revealed genomic features of the novel R. koreansis strain CNH17-7. Hence, we propose R. koreansis strain CNH17-7 as new Rickettsia species.
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The gastrointestinal (GI) tract of shrimp, which is comprised of the stomach, hepatopancreas, and intestine, houses microbial communities that play crucial roles in immune defense, nutrient absorption, and overall health. While the intestine's microbiome has been well-studied, there has been limited research investigating the stomach and hepatopancreas. The present study addresses this gap by profiling the bacterial community in these interconnected GI segments of Pacific whiteleg shrimp. To this end, shrimp samples were collected from a local aquaculture farm in South Korea, and 16S rRNA gene amplicon sequencing was performed. The results revealed significant variations in bacterial diversity and composition among GI segments. The stomach and hepatopancreas exhibited higher Proteobacteria abundance, while the intestine showed a more diverse microbiome, including Cyanobacteria, Actinobacteria, Bacteroidetes, Firmicutes, Chloroflexi, and Verrucomicrobia. Genera such as Oceaniovalibus, Streptococcus, Actibacter, Ilumatobacter, and Litorilinea dominated the intestine, while Salinarimonas, Sphingomonas, and Oceaniovalibus prevailed in the stomach and hepatopancreas. It is particularly notable that Salinarimonas, which is associated with nitrate reduction and pollutant degradation, was prominent in the hepatopancreas. Overall, this study provides insights into the microbial ecology of the Pacific whiteleg shrimp's GI tract, thus enhancing our understanding of shrimp health with the aim of supporting sustainable aquaculture practices.
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Bacterias , Microbioma Gastrointestinal , Hepatopáncreas , Intestinos , Penaeidae , ARN Ribosómico 16S , Animales , Penaeidae/microbiología , Hepatopáncreas/microbiología , ARN Ribosómico 16S/genética , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , República de Corea , Intestinos/microbiología , Filogenia , Estómago/microbiología , Biodiversidad , Acuicultura , ADN Bacteriano/genéticaRESUMEN
Background: This study examines the relationship between physical and mental function and frailty, independently and in conjunction with polypharmacy, among older adults. Methods: This cross-sectional study consisted of 368 participants aged ≥60 years. The participants were categorized into either robust or frail groups using Fried's frailty phenotype. Physical functions were assessed using grip strength, gait speed, Timed Up and Go (TUG), the Five Chair Sit to Stand Test (FCSST) and the Six-Minute Walk Test (SMWT). Mental functions were assessed using cognitive function and depression. Cognitive function was measured using Mini-Mental State Examination (MMSE). Depression was assessed with the Korean version of the Short Geriatric Depression Scale (SGDS). Results: The mean age of study population was 75.4 years. In this population, we identified 78.8% (n = 290) robust participants and 21.2% (n = 78) frail participants. The study examined frailty status (frail vs. non-frail) and frailty with and without polypharmacy using multivariate logistic regressions, adjusting for age and sex. In the logistic regression model estimating the risk of frailty, after adjustments for age, sex, BMI, and number of medications, individuals with low SMWT showed a significantly increased risk of frailty, with an odds ratio (OR) of 8.66 and a 95% confidence interval (CI) of 4.55-16.48. Additionally, global cognitive function was associated with a 1.97-fold increase in frailty risk (95% CI: 1.02-3.67). Moreover, in models adjusted for age, sex, and BMI to assess frailty risk linked to polypharmacy, the TUG, SMWT, and SGDS all showed increased risks, with ORs of 3.65 (95% CI: 1.07-12.47), 5.06 (95% CI: 1.40-18.32), and 5.71 (95% CI: 1.79-18.18), respectively. Conclusions: Physical function (SMWT, FCSST, TUG) and mental function (depression, cognition) were associated with frailty. By comprehensively examining these factors, we will gain valuable insights into frailty and enable more precise strategies for intervention and prevention.
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BACKGROUND: Due to the increasing proportion of older adults in Korea and growing interest in aging, the concepts of oral aging and oral hypofunction have recently been introduced. Thus, it is necessary to investigate the age-specific oral function levels of Korean older adults and develop expert intervention methods for healthy aging. METHODS: Dysphagia, independence of daily living, and oral hypofunction were assessed in 206 older adults living in Wonju, Gangwon State, South Korea. Subjective dysphagia was assessed through self-report questionnaires using the Dysphagia Handicap Index (DHI), the Korean version of Eating Assessment Tool-10, and the Korean version of the Modified Barthel Index. In addition, the oral hypofunction assessment items included decreased chewing ability, occlusal pressure, tongue pressure, oral dryness, and oral cleanliness. RESULTS: DHI increased significantly with age, with those in their 80 s reporting the most difficulty swallowing. Oral function in terms of chewing ability (maximum occlusal pressure and number of remaining teeth), maximum occlusal pressure, and maximum tongue pressure also declined with increasing age. While there was no significant difference in oral dryness by age, those in their 80 s had dry mouth according to the criteria of the oral moisture checking device. CONCLUSIONS: In an assessment of oral function in community-dwelling, independent Korean older adults, the number of items that were assessed as oral hypofunction increased with age. The findings can be used to standardize the oral hypofunction assessment item and develop age-based individualized intervention plans for the early management of oral health and individual oral myofunctional rehabilitation in Korean community-dwelling older adults.
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Trastornos de Deglución , Xerostomía , Humanos , Anciano , Vida Independiente , Presión , Lengua , Salud Bucal , Evaluación GeriátricaRESUMEN
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 & Objective: Aging is a global trend, and Korea is also entering an aging society, which threatens the mental health of the elderly due to isolation, etc. In line with the growing domestic and international interest in elderly issues, this study aimed to identify the effects of depression, stress and self-esteem on the lives of the elderly in South Korea and to provide basic data for welfare measures. Methods: Depression, stress, self-esteem, and quality of life were measured in 104 South Korean seniors (32 men, 72 women, average age 72.94 years old). Differences between groups according to gender and residence type were confirmed. Results: There were no significant differences in stress among the elderly by place of residence, but there were significant differences in quality of life, depression, and self-esteem. Quality of life and self-esteem were higher in private housing than in public housing, and depression was higher in public housing than in private housing. In addition, lower depression and higher self-esteem were correlated with higher quality of life among the elderly. Conclusion: With the global trend of an aging society, it is essential to continue to pay attention to assist the lives of elderly and provide them with practical support and policies. The quality of life of the elderly requires continuous attention and efforts to support and policies for mental health and economic support.
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Patient-physician interaction (PPI) is an important area in medical education, but in-depth discussions on the content of the outcome of patient-doctor education are rare. Therefore, in this study, we will systematically analyze the research on PPI education in Korea. In this study, papers searched with keywords related to PPI education from Korea's academic journal service were targeted according to a systematic literature analysis method. The scope of the study was to include papers published in academic journals that are candidates for Korea Citation Index registration, excluding dissertations, research reports, posters, conference presentations, books, and internet materials. The content included papers targeting medical education and medical school students was set as the range. As a result of the analysis, although communication between PPI has many positive effects in the PPI in medical education at medical schools, obstacles do occur, and various ways to overcome them were suggested. Therefore, although medical interview training between patients and doctors in medical schools is necessary, it was analyzed as being based on overseas research or lacking in specific content. The core of PPI education appears to be medical interviews, and it seems necessary to discuss whether empathy or patient-centered medical care are appropriate as the main principles of PPI education in Korea. Therefore, education on the patient-doctor relationship is an important element in medical humanities and medical humanities education, and it is expected that research and education on this will progress more actively.
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OBJECTIVES: This study aimed to establish the validity-specifically, the sensitivity and specificity-of the screening questionnaire and diagnostic criteria for oral frailty proposed by the Korean Academy of Geriatric Dentistry (KAGD) among community-dwelling older adults. METHODS: This study enrolled 100 participants. Among various definitions of oral frailty, this study used the criteria proposed by Tanaka as the reference test. The screening questionnaire consisted of 11 items for screening physical frailty, chewing ability, swallowing difficulties, oral dryness, and tongue and lip motor function. Each question had a different scoring weight, and if the total score was 1 or higher, an oral frailty diagnostic examination proposed by the KAGD would be recommended. The diagnostic test was the oral frailty diagnostic criteria proposed by the KAGD including 6 measures: chewing ability, occlusal force, tongue pressure, oral dryness, swallowing difficulty, and oral hygiene. If a participant exhibited 2 or more positive measures, this participant was classified as "oral frail." The screening questionnaire was analyzed using a cut-off value of 1 or higher, while the diagnostic criteria utilized a cut-off of 2 or more positive measures. Sensitivity and specificity were calculated. RESULTS: The screening questionnaire showed significant power for screening oral frailty (area under the receiver operating characteristic curve, 0.783; sensitivity, 87.8%; specificity, 52.5%). The diagnostic accuracy of the newly proposed diagnostic criteria was acceptable (sensitivity, 95.1%; specificity, 42.4%). CONCLUSIONS: The newly proposed screening questionnaire and diagnostic criteria in Korea appear to be a useful tool to identify oral frailty in community-dwelling older adults.
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Fragilidad , Humanos , Anciano , Fragilidad/diagnóstico , Vida Independiente , Anciano Frágil , Odontología Geriátrica , Presión , Estudios Transversales , Evaluación Geriátrica , Lengua , Encuestas y Cuestionarios , República de CoreaRESUMEN
INTRODUCTION: Sodium-glucose cotransporter 2 (SGLT2) inhibitors target SGLT2 in renal proximal tubules and promote glycosuria in type 2 diabetes mellitus in humans and animal models, resulting in reduced blood glucose levels. Although clinical trials have shown that SGLT2 inhibitors attenuate the progression of chronic kidney disease, there have been concerns regarding SGLT2-induced acute kidney injury. In this study, we investigated the effect of SGLT2 inhibitors on adriamycin-induced kidney injury in mice. METHODS: Seven-week-old balb/c mice were injected with adriamycin 11.5 mg/kg via the tail vein. Additionally, dapagliflozin was administered via gavage for 2 weeks. The mice were divided into five groups: vehicle, dapagliflozin 3 mg/kg, adriamycin, adriamycin plus dapagliflozin 1 mg/kg, and adriamycin plus dapagliflozin 3 mg/kg. RESULTS: Adriamycin injection reduced the body weight and food and water intakes. Dapagliflozin also decreased the body weight and food and water intakes. Fasting blood glucose and urine volume were not altered by either adriamycin or dapagliflozin. Once adriamycin-induced kidney injury had developed, there were no differences in systolic blood pressure among the groups. Dapagliflozin did not alleviate proteinuria in adriamycin-induced kidney injury. Adriamycin induced significant glomerular and interstitial injury, but dapagliflozin did not attenuate these changes in renal injury. Interestingly, SGLT2 expressions were different between the cortex and medulla of kidneys by dapagliflozin treatment. Dapagliflozin increased SGLT2 expression in medulla, not in cortex. CONCLUSION: Dapagliflozin had no effect on proteinuria or inflammatory changes such as glomerular and tubular damages in adriamycin-induced kidney injury. Our study suggests that dapagliflozin does not protect against adriamycin-induced kidney injury. More experimental studies regarding the effects of SGLT2 inhibitors on various kidney diseases are needed to clarify the underlying mechanisms.
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Diabetes Mellitus Tipo 2 , Glucósidos , Insuficiencia Renal Crónica , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Humanos , Ratones , Animales , Transportador 2 de Sodio-Glucosa/farmacología , Inhibidores del Cotransportador de Sodio-Glucosa 2/farmacología , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Doxorrubicina , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Riñón/metabolismo , Compuestos de Bencidrilo/farmacología , Compuestos de Bencidrilo/uso terapéutico , Insuficiencia Renal Crónica/metabolismo , Proteinuria/tratamiento farmacológico , Peso Corporal , Agua/metabolismoRESUMEN
The spexin-based GALR2 agonist (NS200) is a novel drug, which has shown antidepressant and anxiolytic action in a recent experimental study. In this study, we investigated the effects of NS200 on renal injury in an animal model of type 2 diabetes. Eight-week-old diabetic db/db mice were administered NS200 for 12 weeks. NS200 was intraperitoneally administered at a dose of 1.0â mg/kg/day. Metabolic parameters and structural and molecular changes in the kidneys were compared among the three groups: non-diabetic db/m control, db/db mice, and NS200-treated db/db mice. In db/db mice, NS200 administration did not impact the body weight, food and water intake, urinary volume, fasting blood glucose level, or HbA1c levels. Insulin and glucose tolerance were also unaffected by NS200 treatment. However, NS200 improved urinary albumin excretion and glomerulosclerosis in diabetic kidneys. Activation of TGFß1 and insulin signaling pathways, such as PI3â K /AKT/ERK, were inhibited by NS200. In conclusion, a spexin-based GALR2 agonist attenuated diabetic nephropathy by alleviating renal fibrosis in mice with type 2 diabetes. Spexin-based GALR2 agonists have considerable potential as novel treatment agents in diabetic nephropathy.
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We study evolutionary game dynamics in a growing habitat with vacancies. Fitness is determined by the global effect of the environment and a local prisoner's dilemma among neighbors. We study population growth on a one-dimensional lattice and analyze how the environment affects evolutionary competition. As the environment becomes harsh, an absorbing phase transition from growing populations to extinction occurs. The transition point depends on which strategies are present in the population. In particular, we find a 'cooperative window' in parameter space, where only cooperators can survive. A mutant defector in a cooperative community might briefly proliferate, but over time naturally occurring vacancies separate cooperators from defectors, thereby driving defectors to extinction. Our model reveals that vacancies provide a strong boost for cooperation by spatial selection.
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Conducta Cooperativa , Teoría del Juego , Humanos , Dinámica Poblacional , Crecimiento Demográfico , Ecosistema , Evolución BiológicaRESUMEN
The purpose of this study is to examine how physical function, physical activity, and sleep are related to depressive symptoms in older adults using a nonlinear model. The participants were 283 Korean older adults aged 65 and older who met the study inclusion criteria. Depressive symptoms were measured using the shortened version of the Geriatric Depression Scale in Korean (SGDS-K). Physical activity and sleep time were objectively quantified by continuously monitoring participants over 20 consecutive days using a triaxial accelerometer. Physical function was evaluated using five distinct measurements: grip strength, gait speed, the Timed Up and Go Test (TUG), the Six-Minute Walk Test (SMWT), and the Five Times Sit to Stand Test (FTSST). The SMWT, gait speed, and MVPA exhibited a nonlinear relationship with depressive symptoms. However, other physical functions showed linear relationships. Also, sleep time showed a U-shaped trend starting at approximately 390 min. After adjusting for age, sex, drinking, and smoking in the logistic regression model, SMWT, MVPA, and sleep time were significantly associated with depressive symptoms. The outcomes highlight the importance of considering multiple factors in understanding depression among the elderly, particularly the intricate interactions between these elements and biological rhythms.
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Increasing wealth inequality is a significant global issue that demands attention. While the distribution of wealth varies across countries based on their economic stages, there is a universal trend observed in the distribution function. Typically, regions with lower wealth values exhibit an exponential distribution, while regions with higher wealth values demonstrate a power-law distribution. In this review, we introduce measures that effectively capture wealth inequality and examine wealth distribution functions within the wealth exchange model. Drawing inspiration from the field of econophysics, wealth exchange resulting from economic activities is likened to a kinetic model, where molecules collide and exchange energy. Within this framework, two agents exchange a specific amount of wealth. As we delve into the analysis, we investigate the impact of various factors such as tax collection, debt allowance, and savings on the wealth distribution function when wealth is exchanged. These factors play a crucial role in shaping the dynamics of wealth distribution.
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BACKGROUND: While mobile health apps have demonstrated their potential in revolutionizing health behavior changes, the impact of a mobile community built on these apps on the level of physical activity and mental well-being in cancer survivors remains unexplored. OBJECTIVE: In this randomized controlled trial, we examine the effects of participation in a mobile health community specifically designed for breast cancer survivors on their physical activity levels and mental distress. METHODS: We performed a single-center, randomized, parallel-group, open-label, controlled trial. This trial enrolled women between 20 and 60 years of age with stage 0 to III breast cancer, an Eastern Cooperative Oncology Group performance status of 0, and the capability of using their own smartphone apps. From January 7, 2019, to April 17, 2020, a total of 2,616 patients were consecutively screened for eligibility after breast cancer surgery. Overall, 202 patients were enrolled in this trial, and 186 patients were randomly assigned (1:1) to either the intervention group (engagement in a mobile peer support community using an app for tracking steps; n=93) or the control group (using the app for step tracking only; n=93) with a block size of 10 without stratification. The mobile app provides a visual interface of daily step counts, while the community function also provides rankings among its members and regular notifications encouraging physical activity. The primary end point was the rate of moderate to severe distress for the 24-week study period, measured through an app-based survey using the Distress Thermometer. The secondary end point was the total weekly steps during the 24-week period. RESULTS: After excluding dropouts, 85 patients in the intervention group and 90 patients in the control group were included in the analysis. Multivariate analyses showed that patients in the intervention group had a significantly lower degree of moderate to severe distress (B=-0.558; odds ratio 0.572; P<.001) and a higher number of total weekly step counts (B=0.125; rate ratio 1.132; P<.001) during the 24-week period. CONCLUSIONS: Engagement in a mobile app-based patient community was effective in reducing mental distress and increasing physical activity in breast cancer survivors. TRIAL REGISTRATION: ClinicalTrials.gov NCT03783481; https://classic.clinicaltrials.gov/ct2/show/NCT03783481.
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Neoplasias de la Mama , Supervivientes de Cáncer , Aplicaciones Móviles , Femenino , Humanos , Neoplasias de la Mama/terapia , Ejercicio Físico , Grupos de Autoayuda , Adulto Joven , Adulto , Persona de Mediana EdadRESUMEN
Oligodendrocytes are specialized cells that insulate and support axons with their myelin membrane, allowing proper brain function. Here, we identify lamin A/C (LMNA/C) as essential for transcriptional and functional stability of myelinating oligodendrocytes. We show that LMNA/C levels increase with differentiation of progenitors and that loss of Lmna in differentiated oligodendrocytes profoundly alters their chromatin accessibility and transcriptional signature. Lmna deletion in myelinating glia is compatible with normal developmental myelination. However, altered chromatin accessibility is detected in fully differentiated oligodendrocytes together with increased expression of progenitor genes and decreased levels of lipid-related transcription factors and inner mitochondrial membrane transcripts. These changes are accompanied by altered brain metabolism, lower levels of myelin-related lipids, and altered mitochondrial structure in oligodendrocytes, thereby resulting in myelin thinning and the development of a progressively worsening motor phenotype. Overall, our data identify LMNA/C as essential for maintaining the transcriptional and functional stability of myelinating oligodendrocytes.
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Lámina Nuclear , Transcriptoma , Transcriptoma/genética , Células Cultivadas , Oligodendroglía/metabolismo , Vaina de Mielina/metabolismo , Cromatina/metabolismoRESUMEN
Purpose: To investigate the MRI markers for the prediction of amyloid ß (Aß)-positivity in mild cognitive impairment (MCI) and Alzheimer's disease (AD), and to evaluate the differences in MRI markers between Aß-positive (Aß [+]) and -negative groups using the machine learning (ML) method. Materials and Methods: This study included 139 patients with MCI and AD who underwent amyloid PET-CT and brain MRI. Patients were divided into Aß (+) (n = 84) and Aß-negative (n = 55) groups. Visual analysis was performed with the Fazekas scale of white matter hyperintensity (WMH) and cerebral microbleeds (CMB) scores. The WMH volume and regional brain volume were quantitatively measured. The multivariable logistic regression and ML using support vector machine, and logistic regression were used to identify the best MRI predictors of Aß-positivity. Results: The Fazekas scale of WMH (p = 0.02) and CMB scores (p = 0.04) were higher in Aß (+). The volumes of hippocampus, entorhinal cortex, and precuneus were smaller in Aß (+) (p < 0.05). The third ventricle volume was larger in Aß (+) (p = 0.002). The logistic regression of ML showed a good accuracy (81.1%) with mini-mental state examination (MMSE) and regional brain volumes. Conclusion: The application of ML using the MMSE, third ventricle, and hippocampal volume is helpful in predicting Aß-positivity with a good accuracy.
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It is well-known that interactions between species determine the population composition in an ecosystem. Conventional studies have focused on fixed population structures to reveal how interactions shape population compositions. However, interaction structures are not fixed but change over time due to invasions. Thus, invasion and interaction play an important role in shaping communities. Despite its importance, however, the interplay between invasion and interaction has not been well explored. Here, we investigate how invasion affects the population composition with interactions in open evolving ecological systems considering generalized Lotka-Volterra-type dynamics. Our results show that the system has two distinct regimes. One is characterized by low diversity with abrupt changes of dominant species in time, appearing when the interaction between species is strong and invasion slowly occurs. On the other hand, frequent invasions can induce higher diversity with slow changes in abundances despite strong interactions. It is because invasion happens before the system reaches its equilibrium, which drags the system from its equilibrium all the time. All species have similar abundances in this regime, which implies that fast invasion induces regime shift. Therefore, whether invasion or interaction dominates determines the population composition.
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Ecosistema , Modelos Biológicos , Dinámica PoblacionalRESUMEN
We have previously found that long-term effects of exposure to radiofrequency electromagnetic fields in 5×FAD mice with severe late-stage Alzheimer's disease reduced both amyloid-ß deposition and glial activation, including microglia. To examine whether this therapeutic effect is due to the regulation of activated microglia, we analyzed microglial gene expression profiles and the existence of microglia in the brain in this study. 5×FAD mice at the age of 1.5 months were assigned to sham- and radiofrequency electromagnetic fields-exposed groups and then animals were exposed to 1950 MHz radiofrequency electromagnetic fields at a specific absorption rate of 5 W/kg for 2 hours/day and 5 days/week for 6 months. We conducted behavioral tests including the object recognition and Y-maze tests and molecular and histopathological analysis of amyloid precursor protein/amyloid-beta metabolism in brain tissue. We confirmed that radiofrequency electromagnetic field exposure for 6 months ameliorated cognitive impairment and amyloid-ß deposition. The expression levels of Iba1 (pan-microglial marker) and colony-stimulating factor 1 receptor (CSF1R; regulates microglial proliferation) in the hippocampus in 5×FAD mice treated with radiofrequency electromagnetic fields were significantly reduced compared with those of the sham-exposed group. Subsequently, we analyzed the expression levels of genes related to microgliosis and microglial function in the radiofrequency electromagnetic fields-exposed group compared to those of a CSF1R inhibitor (PLX3397)-treated group. Both radiofrequency electromagnetic fields and PLX3397 suppressed the levels of genes related to microgliosis (Csf1r, CD68, and Ccl6) and pro-inflammatory cytokine interleukin-1ß. Notably, the expression levels of genes related to microglial function, including Trem2, Fcgr1a, Ctss, and Spi1, were decreased after long-term radiofrequency electromagnetic field exposure, which was also observed in response to microglial suppression by PLX3397. These results showed that radiofrequency electromagnetic fields ameliorated amyloid-ß pathology and cognitive impairment by suppressing amyloid-ß deposition-induced microgliosis and their key regulator, CSF1R.
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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.