Synergistic nanoarchitecture of mesoporous carbon and carbon nanotubes for lithium-oxygen batteries

A rechargeable lithium–oxygen battery (LOB) operates via the electrochemical formation and decomposition of solid-state Li2O2 on the cathode. The rational design of the cathode nanoarchitectures is thus required to realize high-energy-density and long-cycling LOBs. Here, we propose a cathode nanoarchitecture for LOBs, which is composed of mesoporous carbon (MPC) integrated with carbon nanotubes (CNTs). The proposed design has the advantages of the two components. MPC provides sufficient active sites for the electrochemical reactions and free space for Li2O2 storage, while CNT forests serve as conductive pathways for electron and offer additional reaction sites. Results show that the synergistic architecture of MPC and CNTs leads to improvements in the capacity (~ 18,400 mAh g− 1), rate capability, and cyclability (~ 200 cycles) of the CNT-integrated MPC cathode in comparison with MPC. © 2021, The Author(s).1

The socio-economic transition and health professions education in Mongolia: a qualitative study

Background Former socialist countries have undergone a socio-economic transition in recent decades. New challenges for the healthcare system have arisen in the transition economy, leading to demands for better management and development of the health professions. However, few studies have explored the effects of this transition on health professions education. Thus, we investigated the effects of the socio-economic transition on the health professions education system in Mongolia, a transition economy country, and to identify changes in requirements. Methods We used a multi-level perspective to explore the effects of the transition, including the input, process, and output levels of the health professions education system. The input level refers to planning and management, the process level refers to the actual delivery of educational services, and the output level refers to issues related to the health professionals, produced by the system. This study utilized a qualitative research design, including document review and interviews with local representatives. Content analysis and the constant comparative method were used for data analysis. Results We explored tensions in the three levels of the health professions education system. First, medical schools attained academic authority for planning and management without proper regulation and financial support. The government sets tuition fees, which are the only financial resource of medical schools; thus, medical schools attempt to enroll more students in order to adapt to the market environment. Second, the quality of educational services varies across institutions due to the absence of a core curriculum and differences in the learning environment. After the transition, the number of private medical schools rapidly increased without quality control, while hospitals started their own specialized training programs. Third, health professionals are struggling to maintain their professional values and development in the market environment. Fixed salaries lead to a lack of motivation, and quality evaluation measures more likely reflect government control than quality improvement. Conclusions Mongolia continues to face the consequences of the socio-economic transition. Medical schools lack of financial authority, the varying quality of educational services, and poor professional development are the major adverse effects. Finding external financial support, developing a core curriculum, and reforming a payment system are recommended

Evaluation of an international faculty development program for developing countries in Asia: the Seoul Intensive Course for Medical Educators

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.Abstract Background The issue of collaboration in medical education is becoming prominent. Some faculty development programs have suggested an approach for promoting collaboration on a global level. However, non-English-speaking developing countries in Asia, especially in Southeast Asia, do not take advantage of them due to their unique context, such as language and culture. To address these issues, Seoul National University College of Medicine initiated a 6-week international faculty development program called the Seoul Intensive Course for Medical Educators for 16 fellows from five Asian countries (Cambodia, Laos, Mongolia, Myanmar, and Vietnam). The aim of this study is to report the evaluation results of the outcome of the program and discuss better ways of collaborating with developing countries. Methods Three levels of collaboration—intraorganizational, intranational, and international—were central initiatives of the program. Prior to setting up the program details, we first established four design principles, following which the contents, materials, and facilitators were determined to maintain consistency with the design principles. The evaluation of the program was done with Kirkpatricks four-level model. Most of the evaluation data for level 1 were collected by two questionnaires, the post-module survey and the post-program survey. Portfolios and progress reports were mainly used to collect outcome data for levels 2 and 3, respectively. Results The reaction was generally positive throughout the program and there was a significant correlation between satisfaction and relevance to ones job or needs. Despite the fellows propensity for overestimating themselves, both the evaluators and fellows reported that there was significant improvement in learning. Opinions on the impact or urgency of the topics were slightly different from country to country; however, the answers regarding feasibility were fairly similar. Moreover, we could observe from the post-program progress reports that the transfer of learning was actively in progress, mainly for topics that were highly feasible. Conclusions These results show that the program was successful in terms of its effectiveness. Consistent and timely support is essential for the sustainable development of the medical education systems in these countries. Further understanding of the underlying factors on transfer (level 3) could improve the effectiveness of faculty development programs for developing countries

Etiquette for medical students email communication with faculty members: a single-institution study

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.Abstract Background Email is widely used as a means of communication between faculty members and students in medical education because of its practical and educational advantages. However, because of the distinctive nature of medical education, students inappropriate email etiquette may adversely affect their learning as well as faculty members perception of them. Little data on medical students competency in professional email writing is available; therefore, this study explored the strengths and weaknesses of medical students email etiquette and factors that contribute to professional email writing. Methods A total of 210 emails from four faculty members at Seoul National University College of Medicine were collected. An evaluation criteria and a scoring rubric were developed based on the various email-writing guidelines. The rubric comprised 10 items, including nine items for evaluation related to the email components and one item for the assessment of global impression of politeness. Three evaluators independently assessed all emails according to the criteria. Results Students were identified as being 61.0 % male and 52.8 % were in the undergraduate-entry program. The sum of each component score was 62.21 out of 100 and the mean value for global impression was 2.6 out of 4. The results demonstrated that students email etiquettes remained low-to-mediocre for most criteria, except for readability and honorifics. Three criteria, salutation (r=0.668), closing (r=0.653), and sign-off (r=0.646), showed a strong positive correlation with the global impression of politeness. Whether a student entered a graduate-entry program or an undergraduate-entry program significantly contributed to professional email writing after other variables were controlled. Conclusions Although students in the graduate-entry program demonstrated a relatively superior level of email etiquette, the majority of medical students did not write emails professionally. Educating all medical students in email etiquette may well contribute to the improvement of student–faculty relationships as well as their email writing

Arsenic trioxide concentration determines the fate of Ewing’s sarcoma family tumors and neuroblastoma cells in vitro

AbstractArsenic trioxide (As2O3) induces both the differentiation and apoptosis of acute promyelocytic leukemia cells in a concentration dependent manner. We assessed the effects of As2O3 in CADO-ES Ewing’s sarcoma (ES), JK-GMS peripheral primitive neuroectodermal tumor (PNET), and SH-SY5Y neuroblastoma cells, as they share common histogenetic backgrounds. As2O3 at low concentrations (0.1–1μM) induced SH-SY5Y differentiation, and whereas PNET cells acquired a slightly differentiated phenotype, change was minimal in ES cells. Extracellular signal-regulated kinase 2 (ERK2) was activated at low As2O3 concentrations, and PD98059, an inhibitor of MEK-1, blocked SH-SY5Y cell differentiation by As2O3. High concentrations (2–10μM) of As2O3 induced the apoptosis in all three cell lines, and this was accompanied by the activation of c-jun N-terminal kinase. The generation of H2O2 and activation of caspase 3 were identified as critical components of As2O3-induced apoptosis in all of the above cell lines. Fibroblast growth factor 2 enhanced As2O3-induced apoptosis in JK-GMS cells. The overall effects of As2O3 strongly suggest that it has therapeutic potential for the treatment of ES/PNET

A functional regulatory variant of MYH3 influences muscle fiber-type composition and intramuscular fat content in pigs

Muscle development and lipid accumulation in muscle critically affect meat quality of livestock. However, the genetic factors underlying myofiber-type specification and intramuscular fat (IMF) accumulation remain to be elucidated. Using two independent intercrosses between Western commercial breeds and Korean native pigs (KNPs) and a joint linkage-linkage disequilibrium analysis, we identified a 488.1-kb region on porcine chromosome 12 that affects both reddish meat color (a*) and IMF. In this critical region, only the MYH3 gene, encoding myosin heavy chain 3, was found to be preferentially overexpressed in the skeletal muscle of KNPs. Subsequently, MYH3-transgenic mice demonstrated that this gene controls both myofiber-type specification and adipogenesis in skeletal muscle. We discovered a structural variant in the promotor/regulatory region of MYH3 for which Q allele carriers exhibited significantly higher values of a* and IMF than q allele carriers. Furthermore, chromatin immunoprecipitation and cotransfection assays showed that the structural variant in the 5-flanking region of MYH3 abrogated the binding of the myogenic regulatory factors (MYF5, MYOD, MYOG, and MRF4). The allele distribution of MYH3 among pig populations worldwide indicated that the MYH3 Q allele is of Asian origin and likely predates domestication. In conclusion, we identified a functional regulatory sequence variant in porcine MYH3 that provides novel insights into the genetic basis of the regulation of myofiber type ratios and associated changes in IMF in pigs. The MYH3 variant can play an important role in improving pork quality in current breeding programs

A functional regulatory variant of MYH3 influences muscle fiber-type composition and intramuscular fat content in pigs

Muscle development and lipid accumulation in muscle critically affect meat quality of livestock. However, the genetic factors underlying myofiber-type specification and intramuscular fat (IMF) accumulation remain to be elucidated. Using two independent intercrosses between Western commercial breeds and Korean native pigs (KNPs) and a joint linkage-linkage disequilibrium analysis, we identified a 488.1-kb region on porcine chromosome 12 that affects both reddish meat color (a*) and IMF. In this critical region, only the MYH3 gene, encoding myosin heavy chain 3, was found to be preferentially overexpressed in the skeletal muscle of KNPs. Subsequently, MYH3-transgenic mice demonstrated that this gene controls both myofiber-type specification and adipogenesis in skeletal muscle. We discovered a structural variant in the promotor/regulatory region of MYH3 for which Q allele carriers exhibited significantly higher values of a* and IMF than q allele carriers. Furthermore, chromatin immunoprecipitation and cotransfection assays showed that the structural variant in the 5′-flanking region of MYH3 abrogated the binding of the myogenic regulatory factors (MYF5, MYOD, MYOG, and MRF4). The allele distribution of MYH3 among pig populations worldwide indicated that the MYH3 Q allele is of Asian origin and likely predates domestication. In conclusion, we identified a functional regulatory sequence variant in porcine MYH3 that provides novel insights into the genetic basis of the regulation of myofiber type ratios and associated changes in IMF in pigs. The MYH3 variant can play an important role in improving pork quality in current breeding programs.info:eu-repo/semantics/publishedVersio

Hematopoietic Differentiation of Embryoid Bodies Derived from the Human Embryonic Stem Cell Line SNUhES3 in Co-culture with Human Bone Marrow Stromal Cells

Human embryonic stem (ES) cells can be induced to differentiate into hematopoietic precursor cells via two methods: the formation of embryoid bodies (EBs) and co-culture with mouse bone marrow (BM) stromal cells. In this study, the above two methods have been combined by co-culture of human ES-cell-derived EBs with human BM stromal cells. The efficacy of this method was compared with that using EB formation alone. The undifferentiated human ES cell line SNUhES3 was allowed to form EBs for two days, then EBs were induced to differentiate in the presence of a different serum concentration (EB and EB/high FBS group), or co-cultured with human BM stromal cells (EB/BM co-culture group). Flow cytometry and hematopoietic colony-forming assays were used to assess hematopoietic differentiation in the three groups. While no significant increase of CD34+/CD45- or CD34+/CD38- cells was noted in the three groups on days 3 and 5, the percentage of CD34+/CD45- cells and CD34+/CD38- cells was significantly higher in the EB/BM co-culture group than in the EB and EB/high FBS groups on day 10. The number of colony-forming cells (CFCs) was increased in the EB/BM co-culture group on days 7 and 10, implying a possible role for human BM stromal cells in supporting hematopoietic differentiation from human ES cell-derived EBs. These results demonstrate that co-culture of human ES-cell-derived EBs with human BM stromal cells might lead to more efficient hematopoietic differentiation from human ES cells cultured alone. Further study is warranted to evaluate the underlying mechanism

Two-year Clinical Outcomes of Patients with Long Segments Drug-Eluting Stents: Comparison of Sirolimus-Eluting Stent with Paclitaxel-Eluting Stent

Limited data are available on the long-term clinical efficacy of drug-eluting stent (DES) in diffuse long lesions. From May 2006 to May 2007, a total of 335 consecutive patients (374 lesions) were underwent percutaneous coronary intervention with implantation of long DES (≥ 30 mm) in real world practice. Eight-month angiographic outcomes and 2-yr clinical outcomes were compared between SES (n = 218) and PES (n = 117). Study endpoints were major adverse cardiac events including cardiac death, myocardial infarction, target-lesion revascularization, target-vessel revascularization and stent thrombosis. Baseline characteristics were similar in the two groups as were mean stent length (44.9 ± 15.2 mm in SES and 47.4 ± 15.9 in PES, P = 0.121). Late loss at 8 months follow-up was significantly lower in SES than in PES group (0.4 ± 0.6 mm in SES vs 0.7 ± 0.8 mm in PES, P = 0.007). Mean follow-up duration was 849 ± 256 days, and 2-yr cumulative major adverse cardiac events were significantly lower in the SES than in the PES group (5.5% in SES vs 15.4% in PES, P = 0.003). In conclusion, long-term DES use in diffuse long coronary lesions is associated with favorable results, with SES being more effective and safer than PES in this real-world clinical experience