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Childhood neglect and/or abuse can induce mental health conditions with unknown mechanisms. Here, we identified stress hormones as strong inducers of astrocyte-mediated synapse phagocytosis. Using in vitro, in vivo, and human brain organoid experiments, we showed that stress hormones increased the expression of the Mertk phagocytic receptor in astrocytes through glucocorticoid receptor (GR). In post-natal mice, exposure to early social deprivation (ESD) specifically activated the GR-MERTK pathway in astrocytes, but not in microglia. The excitatory post-synaptic density in cortical regions was reduced in ESD mice, and there was an increase in the astrocytic engulfment of these synapses. The loss of excitatory synapses, abnormal neuronal network activities, and behavioral abnormalities in ESD mice were largely prevented by ablating GR or MERTK in astrocytes. Our work reveals the critical roles of astrocytic GR-MERTK activation in evoking stress-induced abnormal behaviors in mice, suggesting GR-MERTK signaling as a therapeutic target for stress-induced mental health conditions.
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Astrócitos , Fagocitose , Estresse Psicológico , Animais , Criança , Humanos , Camundongos , Astrócitos/metabolismo , c-Mer Tirosina Quinase/genética , Hormônios/metabolismo , Sinapses/metabolismo , Estresse Psicológico/metabolismoRESUMO
Glia contribute to synapse elimination through phagocytosis in the central nervous system. Despite the important roles of this process in development and neurological disorders, the identity and regulation of the "eat-me" signal that initiates glia-mediated phagocytosis of synapses has remained incompletely understood. Here, we generated conditional knockout mice with neuronal-specific deletion of the flippase chaperone Cdc50a, to induce stable exposure of phosphatidylserine, a well-known "eat-me" signal for apoptotic cells, on the neuronal outer membrane. Surprisingly, acute Cdc50a deletion in mature neurons causes preferential phosphatidylserine exposure in neuronal somas and specific loss of inhibitory post-synapses without effects on other synapses, resulting in abnormal excitability and seizures. Ablation of microglia or the deletion of microglial phagocytic receptor Mertk prevents the loss of inhibitory post-synapses and the seizure phenotype, indicating that microglial phagocytosis is responsible for inhibitory post-synapse elimination. Moreover, we found that phosphatidylserine is used for microglia-mediated pruning of inhibitory post-synapses in normal brains, suggesting that phosphatidylserine serves as a general "eat-me" signal for inhibitory post-synapse elimination.
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Microglia/metabolismo , Fosfatidilserinas/metabolismo , Convulsões/fisiopatologia , Sinapses/fisiologia , c-Mer Tirosina Quinase/metabolismo , Animais , Encéfalo/fisiopatologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Fagocitose/fisiologia , Convulsões/genética , c-Mer Tirosina Quinase/genéticaRESUMO
The adolescent social experience is essential for the maturation of the prefrontal cortex in mammalian species. However, it still needs to be determined which cortical circuits mature with such experience and how it shapes adult social behaviors in a sex-specific manner. Here, we examined social-approaching behaviors in male and female mice after postweaning social isolation (PWSI), which deprives social experience during adolescence. We found that the PWSI, particularly isolation during late adolescence, caused an abnormal increase in social approaches (hypersociability) only in female mice. We further found that the PWSI female mice showed reduced parvalbumin (PV) expression in the left orbitofrontal cortex (OFCL). When we measured neural activity in the female OFCL, a substantial number of neurons showed higher activity when mice sniffed other mice (social sniffing) than when they sniffed an object (object sniffing). Interestingly, the PWSI significantly reduced both the number of activated neurons and the activity level during social sniffing in female mice. Similarly, the CRISPR/Cas9-mediated knockdown of PV in the OFCL during late adolescence enhanced sociability and reduced the social sniffing-induced activity in adult female mice via decreased excitability of PV+ neurons and reduced synaptic inhibition in the OFCL Moreover, optogenetic activation of excitatory neurons or optogenetic inhibition of PV+ neurons in the OFCL enhanced sociability in female mice. Our data demonstrate that the adolescent social experience is critical for the maturation of PV+ inhibitory circuits in the OFCL; this maturation shapes female social behavior via enhancing social representation in the OFCL SIGNIFICANCE STATEMENT Adolescent social isolation often changes adult social behaviors in mammals. Yet, we do not fully understand the sex-specific effects of social isolation and the brain areas and circuits that mediate such changes. Here, we found that adolescent social isolation causes three abnormal phenotypes in female but not male mice: hypersociability, decreased PV+ neurons in the left orbitofrontal cortex (OFCL), and decreased socially evoked activity in the OFCL Moreover, parvalbumin (PV) deletion in the OFCL in vivo caused the same phenotypes in female mice by increasing excitation compared with inhibition within the OFCL Our data suggest that adolescent social experience is required for PV maturation in the OFCL, which is critical for evoking OFCL activity that shapes social behaviors in female mice.
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Neurônios , Parvalbuminas , Masculino , Camundongos , Animais , Feminino , Parvalbuminas/metabolismo , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Comportamento Social , Isolamento Social , Interneurônios/fisiologia , MamíferosRESUMO
Donation after circulatory death (DCD) is driving the increase in deceased organ donors in the United States. Normothermic regional perfusion (NRP) and ex situ machine perfusion (es-MP) have been instrumental in improving liver transplant outcomes and graft utilization. This study examines the current landscape of liver utilization from cardiac DCD donors in the United States. Using the United Network for Organ Sharing Standard Transplant Analysis and Research file, all adult (≥18 years old) DCD donors in the United States from which the heart was used for transplantation from October 1, 2020, to September 30, 2023, were compared by procurement technique (NRP versus super rapid recovery [SRR]) and storage strategy (es-MP versus static cold storage). One hundred eighty-eight livers were transplanted from 309 thoracoabdominal NRP donors (61% utilization) versus 305 (56%) liver transplants from 544 SRR donors. es-MP was used in 20% (n = 38) of NRP cases versus 32% (98) of SRR cases. Of the liver grafts, 281 (59%) were exposed to NRP, es-MP, or both. While there is widespread utilization of machine perfusion, more research is needed to determine optimal graft management strategies, particularly concerning the use of multiple technologies in complementary ways. More complete data collection is necessary at a national level to address these important research questions.
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Carbon black (CB) particles that can absorb from near ultraviolet to infrared rays are well dispersed into an isotropic dielectric liquid and their optical properties can be kept even under exposure to sunlight over a long time. The shutter which controls the position of CB particles by electrophoretic force can be applied to switchable light shutters for windows in buildings and automobiles for the purpose of energy savings. Here, a wideband light shutter with three terminal electrodes is proposed, exhibiting excellent dark (transmittance ≈1.4%) and transparent state (transmittance >60%). The device operates at a low field intensity of about 1 V µm-1 to obtain transparent state and its wide temperature range operation from -50 to 120 °C is confirmed while conventional liquid crystal-based shutter cannot perform such levels due to a limited temperature range in the nematic phase. In addition, haze is minimized in a transparent state by adopting an insulation layer over electrodes and a solution is found to keep a transparent state without applying power. It is believed that the proposed broadband shutter with fast response time could open a new chapter in switchable windows owing to its low power consumption and working in a wide temperature range.
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INTRODUCTION: Normothermic regional perfusion (NRP) represents an innovative technology that improves the outcomes for liver and kidney recipients of donation after circulatory determination of death (DCD) organs but protocols for abdominal-only NRP (A-NRP) DCD are lacking in the US. METHODS: We describe the implementation and expansion strategies of a transplant-center-based A-NRP DCD program that has grown in volume, geographical reach, and donor acceptance parameters, presented as four eras. RESULTS: In the implementation era, two donors were attempted, and one liver graft was transplanted. In the local expansion era, 33% of attempted donors resulted in transplantation and 42% of liver grafts from donors who died within the functional warm ischemic time (fWIT) limit were transplanted. In the Regional Expansion era, 25% of attempted donors resulted in transplantation and 50% of liver grafts from donors who died within the fWIT limit were transplanted. In the Donor Acceptance Expansion era, 46% of attempted donors resulted in transplantation and 72% of liver grafts from donors who died within the fWIT limit were transplanted. Eight discarded grafts demonstrated a potential opportunity for utilization. CONCLUSION: The stepwise approach to building an A-NRP program described here can serve as a model for other transplant centers.
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Preservação de Órgãos , Obtenção de Tecidos e Órgãos , Humanos , Preservação de Órgãos/métodos , Perfusão/métodos , Doadores de Tecidos , Morte , Sobrevivência de EnxertoRESUMO
INTRODUCTION: Around 12% of Europeans and 20% of Americans have at least one tattoo. Tattoo inks, the substances used to create tattoos on the body, consist of chemicals that contain formaldehyde, which can be harmful to human health. The amount of formaldehyde present in commercially available tattoo inks and its causes are not well understood. METHODS: We investigated the levels of formaldehyde in tattoo ink products sold in different countries and identified the factors contributing to its production. We also explored methods to reduce formaldehyde generation in tattoo inks. Seven tattoo inks from various brands were tested. RESULTS: Formaldehyde release was predominantly associated with gamma radiation sterilization. Formaldehyde levels were observed to be higher in compositions containing organic components compared to those with inorganic components, irrespective of sterilization method and container type. Glycerin released over seven times more formaldehyde than other components during gamma-ray sterilization. CONCLUSION: The results suggest that the presence of hydroxyl groups in carbon organic compounds in tattoo ink leads to photodegradation during gamma-ray radiation sterilization, resulting in increased concentrations of formaldehyde. Further research is needed to examine the chemical reactions occurring during sterilization processes and identify alternative sterilization methods that minimize formaldehyde formation. Additionally, the development of tattoo inks with reduced formaldehyde content and the establishment of strict quality control measures can help ensure the safety of tattooing practices.
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Tatuagem , Humanos , Tinta , Formaldeído , EsterilizaçãoRESUMO
Importance: Uterus transplant in women with absolute uterine-factor infertility offers the possibility of carrying their own pregnancy. Objective: To determine whether uterus transplant is feasible and safe and results in births of healthy infants. Design, Setting, and Participants: A case series including 20 participants with uterine-factor infertility and at least 1 functioning ovary who underwent uterus transplant in a large US tertiary care center between September 14, 2016, and August 23, 2019. Intervention: The uterus transplant (from 18 living donors and 2 deceased donors) was surgically placed in an orthotopic position with vascular anastomoses to the external iliac vessels. Participants received immunosuppression until the transplanted uterus was removed following 1 or 2 live births or after graft failure. Main Outcomes and Measures: Uterus graft survival and subsequent live births. Results: Of 20 participants (median age, 30 years [range, 20-36]; 2 Asian, 1 Black, and 16 White), 14 (70%) had a successful uterus allograft; all 14 recipients gave birth to at least 1 live-born infant. Eleven of 20 recipients had at least 1 complication. Maternal and/or obstetrical complications occurred in 50% of the successful pregnancies, with the most common being gestational hypertension (2 [14%]), cervical insufficiency (2 [14%]), and preterm labor (2 [14%]). Among the 16 live-born infants, there were no congenital malformations. Four of 18 living donors had grade 3 complications. Conclusions and Relevance: Uterus transplant was technically feasible and was associated with a high live birth rate following successful graft survival. Adverse events were common, with medical and surgical risks affecting recipients as well as donors. Congenital abnormalities and developmental delays have not occurred to date in the live-born children. Trial Registration: ClinicalTrials.gov Identifier: NCT02656550.
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Infertilidade Feminina , Nascido Vivo , Útero , Adulto , Feminino , Humanos , Gravidez , Adulto Jovem , Estudos de Viabilidade , Sobrevivência de Enxerto , Infertilidade Feminina/cirurgia , Infertilidade Feminina/etiologia , Doadores Vivos , Útero/transplante , Útero/anormalidades , Estudos ProspectivosRESUMO
In patients with chronic pancreatitis, pancreatic calcification is a risk factor for diabetes development, poor islet yield, and metabolic outcomes after total pancreatectomy with islet autotransplantation (TPIAT). We investigated whether calcification pattern based on computed tomography is associated with outcomes using our database of 200 consecutive TPIAT procedures. Three groups were compared: noncalcification (NC); focal calcification, limited to the pancreas head, body, or tail; and diffuse calcification (DC), with calcification in >2 sections. Maximum changes in outcomes were seen in the DC vs focal calcification group. In the DC group, preoperative hemoglobin A1c levels were higher (P < .01), and stimulated C-peptide levels were lower (P < .01) than in the NC group. Islet isolation from the DC pancreas resulted in the lowest islet equivalent (IEQ) yield and IEQ/kg among the 3 groups (P < .0001), with no insulin independence 12 months posttransplant (P < .05 vs NC group). Notably, at 12 months, the DC group was 91.7% narcotic-free, significantly higher than the NC group (P < .05). Although DC is a sign of diabetes risk after TPIAT, the DC group showed exceptional pain relief. These findings suggest that TPIAT can be beneficial for patients with chronic pancreatitis with severe calcification.
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Diabetes Mellitus , Transplante das Ilhotas Pancreáticas , Pancreatite Crônica , Humanos , Pancreatectomia/efeitos adversos , Pancreatectomia/métodos , Transplante Autólogo , Transplante das Ilhotas Pancreáticas/efeitos adversos , Transplante das Ilhotas Pancreáticas/métodos , Resultado do Tratamento , Pâncreas/cirurgia , Pancreatite Crônica/cirurgiaRESUMO
Air pollution is a severe concern globally as it disturbs the health conditions of living beings and the environment because of the discharge of acetone molecules. Metal oxide semiconductor (MOS) nanomaterials are crucial for developing efficient sensors because of their outstanding chemical and physical properties, empowering the inclusive developments in gas sensor productivity. This review presents the ZnO nanostructure state of the art and notable growth, and their structural, morphological, electronic, optical, and acetone-sensing properties. The key parameters, such as response, gas detection limit, sensitivity, reproducibility, response and recovery time, selectivity, and stability of the acetone sensor, have been discussed. Furthermore, gas-sensing mechanism models based on MOS for acetone sensing are reported and discussed. Finally, future possibilities and challenges for MOS (ZnO)-based gas sensors for acetone detection have also been explored.
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Líquidos Corporais , Nanoestruturas , Óxido de Zinco , Acetona , Reprodutibilidade dos Testes , Gases Nobres , ÓxidosRESUMO
BACKGROUND: Although research experience is important for medical students, it is difficult to develop research skills only through a formal curriculum. To develop research programs that address the authentic needs of students and align with the entirety of the medical school curriculum, a learner-centered approach may be more effective than an instructor-centered approach. This study investigates medical student perspectives on factors that help them develop research competency. METHODS: Hanyang University College of Medicine in South Korea operates the Medical Scientist Training Program (MSTP) as a supplement to its formal curriculum. Semi-structured interviews were held with 18 students (20 cases) in the program, and qualitative content analysis was performed using the software tool MAXQDA20. RESULTS: The findings are discussed in relation to three domains: learner engagement, instructional design, and program development. The students were more engaged when they perceived the program as a new experience, had prior research experience, wanted to make a good impression, and felt a sense of contribution. In terms of instructional design, they positively participated in research when their supervisors respected them, set clear tasks, provided constructive feedback, and invited them into the research community. In particular, the students highly valued relationships with their professors, and these relationships served not only as a main motivating factor in their research participation but also affected their college lives and careers. CONCLUSIONS: The longitudinal relationship between students and professors has newly emerged in the Korean context as a factor that strengthens student engagement in research and the complementary relationship between formal curriculum and MSTP was highlighted to encourage student engagement in research.
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Educação de Graduação em Medicina , Estudantes de Medicina , Humanos , Currículo , Pesquisa Qualitativa , AtitudeRESUMO
A chemotherapeutic approach is crucial in malignancy management, which is often challenging due to the development of chemoresistance. Over time, chemo-resistant cancer cells rapidly repopulate and metastasize, increasing the recurrence rate in cancer patients. Targeting these destined cancer cells is more troublesome for clinicians, as they share biology and molecular cross-talks with normal cells. However, the recent insights into the metabolic profiles of chemo-resistant cancer cells surprisingly illustrated the activation of distinct pathways compared with chemo-sensitive or primary cancer cells. These distinct metabolic dynamics are vital and contribute to the shift from chemo-sensitivity to chemo-resistance in cancer. This review will discuss the important metabolic alterations in cancer cells that lead to drug resistance.
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Resistencia a Medicamentos Antineoplásicos , Neoplasias , Humanos , Glucose/metabolismoRESUMO
The 2020-2025 Dietary Guidelines for Americans* advise incorporating more fruits and vegetables into U.S. residents' diets as part of healthy dietary patterns. Adults should consume 1.5-2 cup-equivalents of fruits and 2-3 cup-equivalents of vegetables daily. A healthy diet supports healthy immune function (1) and helps to prevent obesity, type 2 diabetes, cardiovascular diseases, and some cancers (2); having some of these conditions can predispose persons to more severe illness and death from COVID-19 (3). CDC used the most recent 2019 Behavioral Risk Factor Surveillance system (BRFSS) data to estimate the percentage of states' adult population who met intake recommendations overall and by sociodemographic characteristics for 49 states and the District of Columbia (DC). Overall, 12.3% of adults met fruit recommendations, ranging from 8.4% in West Virginia to 16.1% in Connecticut, and 10.0% met vegetable recommendations, ranging from 5.6% in Kentucky to 16.0% in Vermont. The prevalence of meeting fruit intake recommendations was highest among Hispanic adults (16.4%) and lowest among males (10.1%); meeting vegetable intake recommendations was highest among adults aged ≥51 years (12.5%) and lowest among those living below or close to the poverty level (income to poverty ratio [IPR] <1.25) (6.8%). Additional policies§ and programs that will increase access to fruits and vegetables in places where U.S. residents live, learn, work, and play, might increase consumption and improve health.
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Dieta Saudável/estatística & dados numéricos , Frutas , Política Nutricional , Recomendações Nutricionais , Verduras , Adulto , Sistema de Vigilância de Fator de Risco Comportamental , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sociodemográficos , Estados UnidosRESUMO
Synapses are the fundamental elements of the brain's complicated neural networks. Although the ultrastructure of synapses has been extensively studied, the difference in how synaptic inputs are organized onto distinct neuronal types is not yet fully understood. Here, we examined the cell-type-specific ultrastructure of proximal processes from the soma of parvalbumin-positive (PV+) and somatostatin-positive (SST+) GABAergic neurons in comparison with a pyramidal neuron in the mouse primary visual cortex (V1), using serial block-face scanning electron microscopy. Interestingly, each type of neuron organizes excitatory and inhibitory synapses in a unique way. First, we found that a subset of SST+ neurons are spiny, having spines on both soma and dendrites. Each of those spines has a highly complicated structure that has up to eight synaptic inputs. Next, the PV+ and SST+ neurons receive more robust excitatory inputs to their perisoma than does the pyramidal neuron. Notably, excitatory synapses on GABAergic neurons were often multiple-synapse boutons, making another synapse on distal dendrites. On the other hand, inhibitory synapses near the soma were often single-targeting multiple boutons. Collectively, our data demonstrate that synaptic inputs near the soma are differentially organized across cell types and form a network that balances inhibition and excitation in the V1.
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Neurônios GABAérgicos/ultraestrutura , Células Piramidais/ultraestrutura , Sinapses/ultraestrutura , Córtex Visual/ultraestrutura , Animais , Neurônios GABAérgicos/metabolismo , Imageamento Tridimensional , Camundongos , Microscopia Eletrônica de Varredura , Parvalbuminas/metabolismo , Células Piramidais/metabolismo , Somatostatina/metabolismoRESUMO
BACKGROUND: For medical school students, specialty choice after graduation significantly impacts their future doctor life. Several Korean medical schools have made efforts to prepare career development programs. However, career support programs based on the systematic analysis of medical school students' first to the final year are still lacking. Therefore, this study aims to analyze the students' career preparation of one medical school in Korea using the Career Maturity Inventory (CMI) and Specialty Indecision Scale (SIS) and to explore the relationship between CMI and SIS variables. METHODS: From December 2020 to July 2021, we conducted an online survey of 600 students in years 1 to 4 at Seoul National University College of Medicine. We analyzed the differences between the years of the students through one-way analysis of variance of the CMI and SIS and the relationship between the two instruments by correlation analysis and multiple regression analysis. RESULTS: A total of 198 students completed the survey. The average scores of the CMI variables tended to increase as the year of study went up, and the confidence score of the 1st year students was significantly lower than that of the 2nd and 4th year students. Although there was almost no consistent decrease by year in the SIS variables, 3rd and 4th year students showed significantly lower readiness scores than 1st year students. Additionally, we found that the CMI variables mostly had a negative effect on the SIS variables. CONCLUSION: There is an increasing tendency for career maturity by year of study in Korean medical school students. However, looking at the SIS results, the career concerns vary among the students. Therefore, medical schools can effectively use the SIS to identify the career concerns of students.
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Medicina , Estudantes de Medicina , Escolha da Profissão , Humanos , República da Coreia , Faculdades de Medicina , Inquéritos e QuestionáriosRESUMO
BACKGROUND: For OSCE (Objective Structured Clinical Examination) scoring, medical schools must bring together many clinical experts at the same place, which is very risky in the context of the coronavirus pandemic. However, if the FLEX model with the properties of self-directed learning and offline feedback is applied to OSCE, it is possible to provide a safe and effective evaluation environment for both universities and students through experts' evaluation of self-video clips of medical students. The present study investigated validity of the FLEX model to evaluate OSCE in a small group of medical students. METHODS: Sixteen 3rd grade medical students who failed on OSCE were required to take a make-up examination by videotaping the failed items and submitting them online. The scores between original examination and make-up examination were compared using Paired Wilcoxon Signed Rank Test, and a post-hoc questionnaire was conducted. RESULTS: The score for make-up examination was significantly higher than those for original examination. The significance was maintained even when the score was compared by individual domains of skills and proficiency. In terms of preference, students were largely in favor of self-videotaped examination primarily due to the availability of self-practice. CONCLUSION: The FLEX model can be effectively applied to medical education, especially for evaluation of OSCE.
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Educação Médica , Estudantes de Medicina , Competência Clínica , Humanos , Aprendizagem , Pandemias , Faculdades de MedicinaRESUMO
BACKGROUND: While clinical competency is crucial for traditional East-Asian medical education, available studies on the educational system for fostering clinical performance are scarce. This study aimed to review the educational system, curriculum, facilities, and management of current traditional East-Asian medicine in a well-established university of Korea and develop a Best Practice Framework (BPF) of clinical competency education. METHODS: The clinical competency education system in Pusan National University School of Korean Medicine was systematically described through 5 steps of governance of the educational system, competency of the graduates, educational resources, assessment strategies and tools, and gaps in the curriculum. We also reviewed the experiences in education and the points to be improved. RESULTS: The Office of Traditional Korean Medicine Education governs the development, implementation, and evaluation of the educational curriculum for cultivating students' clinical competency. Medical students have undertaken 39 modules of clinical biomedicine and 21 of traditional medicine during the clinical clerkship courses in an affiliated hospital, Clinical Skill Practice Center, clinical research center, practice lab for medical herb, and other locations. After training, 15 modules of simulated clinical training using standardized patients, students' clinical competency are evaluated by a Clinical Performance Test using a Clinical Performance Examination (CPX) and an Objective Structured Clinical Examination (OSCE) for biomedical and traditional medical skills. CONCLUSIONS: A clinical competency framework is required for a qualified physician of traditional East-Asian medicine. This study reviewed the current well-organized educational system of Korean traditional medicine in detail, which can be used for the BPF of competency-based clinical education. We expect the current study to be a representative reference for establishing an educational system of traditional medicine such as acupuncture and medical herbs in other countries.
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Competência Clínica , Estudantes de Medicina , Educação Baseada em Competências , Currículo , Avaliação Educacional , HumanosRESUMO
Here, we report the synthesis of the WS2 nanorods (NRs) using an eco-friendly and facile hydrothermal method for an acetone-sensing application. This study explores the acetone gas-sensing characteristics of the WS2 nanorod sensor for 5, 10, and 15 ppm concentrations at 25 °C, 50 °C, 75 °C, and 100 °C. The WS2 nanorod sensor shows the highest sensitivity of 94.5% at 100 °C for the 15 ppm acetone concentration. The WS2 nanorod sensor also reveals the outstanding selectivity of acetone compared to other gases, such as ammonia, ethanol, acetaldehyde, methanol, and xylene at 100 °C with a 15 ppm concentration. The estimated selectivity coefficient indicates that the selectivity of the WS2 nanorod acetone sensor is 7.1, 4.5, 3.7, 2.9, and 2.0 times higher than xylene, acetaldehyde, ammonia, methanol, and ethanol, respectively. In addition, the WS2 nanorod sensor also divulges remarkable stability of 98.5% during the 20 days of study. Therefore, it is concluded that the WS2 nanorod can be an excellent nanomaterial for developing acetone sensors for monitoring work/public places.
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Acetona , Nanotubos , Amônia , Xilenos , Metanol , Gases , Etanol , AcetaldeídoRESUMO
According to the 2020-2025 Dietary Guidelines for Americans, persons should consume fruits and vegetables as part of a healthy eating pattern to reduce their risk for diet-related chronic diseases, such as cardiovascular disease, type 2 diabetes, some cancers, and obesity.* A healthy diet is important for healthy growth in adolescence, especially because adolescent health behaviors might continue into adulthood (1). The U.S. Department of Agriculture (USDA) recommends minimum daily intake of 1.5 cups of fruit and 2.5 cups of vegetables for females aged 14-18 years and 2 cups of fruit and 3 cups of vegetables for males aged 14-18 years. Despite the benefits of fruit and vegetable consumption, few adolescents consume these recommended amounts (2-4). In 2013, only 8.5% of high school students met the recommendation for fruit consumption, and only 2.1% met the recommendation for vegetable consumption (2). To update the 2013 data, CDC analyzed data from the 2017 national and state Youth Risk Behavior Surveys (YRBSs) to describe the percentage of students who met intake recommendations, overall and by sex, school grade, and race/ethnicity. The median frequencies of fruit and vegetable consumption nationally were 0.9 and 1.1 times per day, respectively. Nationally, 7.1% of students met USDA intake recommendations for fruits (95% confidence interval [CI] = 4.0-10.3) and 2.0% for vegetables (upper 95% confidence limit = 7.9) using previously established scoring algorithms. State-specific estimates of the percentage of students meeting fruit intake recommendations ranged from 4.0% (Connecticut) to 9.3% (Louisiana), and the percentage meeting vegetable intake recommendations ranged from 0.6% (Kansas) to 3.7% (New Mexico). Additional efforts to expand the reach of existing school and community programs or to identify new effective strategies, such as social media approaches, might help address barriers and improve adolescent fruit and vegetable consumption.