• 제목/요약/키워드: molecular distribution

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Bending of axially functionally graded carbon nanotubes reinforced composite nanobeams

  • Ahmed Drai;Ahmed Amine Daikh;Mohamed Oujedi Belarbi;Mohammed Sid Ahmed Houari;Benoumer Aour;Amin Hamdi;Mohamed A. Eltaher
    • Advances in nano research
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    • 제14권3호
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    • pp.211-224
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    • 2023
  • This work presents a modified analytical model for the bending behavior of axially functionally graded (AFG) carbon nanotubes reinforced composite (CNTRC) nanobeams. New higher order shear deformation beam theory is exploited to satisfy parabolic variation of shear through thickness direction and zero shears at the bottom and top surfaces.A Modified continuum nonlocal strain gradient theoryis employed to include the microstructure and the geometrical nano-size length scales. The extended rule of the mixture and the molecular dynamics simulations are exploited to evaluate the equivalent mechanical properties of FG-CNTRC beams. Carbon nanotubes reinforcements are distributed axially through the beam length direction with a new power graded function with two parameters. The equilibrium equations are derived with associated nonclassical boundary conditions, and Navier's procedure are used to solve the obtained differential equation and get the response of nanobeam under uniform, linear, or sinusoidal mechanical loadings. Numerical results are carried out to investigate the impact of inhomogeneity parameters, geometrical parameters, loadings type, nonlocal and length scale parameters on deflections and stresses of the AFG CNTRC nanobeams. The proposed model can be used in the design and analysis of MEMS and NEMS systems fabricated from carbon nanotubes reinforced composite nanobeam.

우리나라 의사 국가시험 필기시험(2016-2018)의 기초의학 역량 평가 현황의 분석 (Analysis of Basic Medicine-Related Questions in the Korean Medical Licensing Examination (2016-2018))

  • 국현;오세옥;이덕주;기선호;전용성
    • 의학교육논단
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    • 제25권1호
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    • pp.68-77
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    • 2023
  • Basic medical education is important for developing the competencies of medical doctors, and it includes basic biomedical sciences, preventive medicine, medical ethics, and clinical science. This study aimed to reveal the current status of the Korean Medical Licensing Examination (KMLE) regarding its evaluation of competencies in basic biomedical sciences. The basic medicine-related questions were screened and selected from the test forms of the KMLE (2016-2018) by personnel conducting basic biomedical science education, and the selected questions were analyzed by three independent groups of undergraduate students at Chonnam National University Medical School in terms of the learning outcomes of basic medical education. The study scope includes the proportion of basic medicine-related questions, which consist of basic medicine questions and basic medicine-related clinical medicine questions, its annual change, discipline distribution, and associated learning outcomes. The average proportions of basic biomedical sciences, preventive medicine and medical law, and clinical sciences were 2.3%, 5.8%, and 91.9% of all questions, respectively. The proportion of basic medicine-related questions, except those on preventive medicine and medical law, was 22.0% of the total, and questions on pharmacology and microbiology accounted for 83.0% of the basic medicine-related questions. The proportion of sub-enabling learning outcomes linked with basic medicine-related questions comprised 14.0% of the total outcomes for basic biomedical sciences and 30.4% for preventive medicine and medical law. It is concluded that the KMLE questions may not sufficiently cover the essential competencies of basic medical education for medical doctors, and the KMLE may need to be improved with regard to competencies in basic biomedical sciences.

Correlation of the 2223 percentage before the first intermediate pressing and the transport property of the fully processed Bi-2223/Ag tapes

  • Jiang, C.H.;Yoo, J.M.;Ko, J.W.;Kim, Y.K.;Chung, H.S.
    • Progress in Superconductivity
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    • 제4권1호
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    • pp.94-98
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    • 2002
  • Two kinds of multifilament Bi-2223/Ag tapes, which are different in the precursor calcination temperatures, were heat treated for different time (12, 20, 30, 50, 70, or 100 h) firstly to obtain varied B2223 contents, and then followed by the same pressing and sintering cycles. The relation of the 2223 phase contents after the first sintering and the transport property of the fully processed tapes was studied. The results show that 75-80% 2223 phase formed in tapes before the first cold pressing is beneficial to get a high $I_{c}$ in the final tapes. Compensating the total heat treatment time of the tapes first sintered for 20 h to the same length as that first sintered for 50 h in the subsequent sintering stages, different $I_{c}$ enhancements were observed in these two tapes. No improvement on $I_{c}$ was found in the tape made from the powder calcined at higher temperature, whereas for the tape prepared with the lower temperature calcined powder, the $I_{c}$ was increased to the same level as that first sintered for 50 h. The 2223 contents before the intermediate mechanical work is related to the residual reactants, especially to the liquid phase, which is of vital importance to the phase conversion and healing microcracks, meanwhile, to the size and distribution of the non-superconducting secondary phases. The lower temperature calcined powder resulted in slow formation of 2223 phase, but also provided more reactants and liquid phase for the further phase conversion, as a consequence, for the Improvement of $I_{c}$. c/.

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Unveiling mesophotic diversity in Hawai'i: two new species in the genera Halopeltis and Leptofauchea (Rhodymeniales, Rhodophyta)

  • Erika A., Alvarado;Feresa P., Cabrera;Monica O., Paiano;James T., Fumo;Heather L., Spalding;Celia M., Smith;Jason C., Leonard;Keolohilani H., Lopes Jr.;Randall K., Kosaki;Alison R., Sherwood
    • ALGAE
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    • 제37권4호
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    • pp.249-264
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    • 2022
  • Two genera of the Rhodymeniales, Halopeltis and Leptofauchea, are here reported for the first time from the Hawaiian Islands and represent the deepest records for both genera. Molecular phylogenetic analyses of cytochrome oxidase subunit I (COI), rbcL, and large subunit ribosomal DNA (LSU) sequences for Hawaiian specimens of Leptofauchea revealed one well-supported clade of Hawaiian specimens and three additional lineages. One of these clades is described here as Leptofauchea huawelau sp. nov., and is thus far known only from mesophotic depths at Penguin Bank in the Main Hawaiian Islands. L. huawelau sp. nov. is up to 21 cm, and is the largest known species. An additional lineage identified in the LSU and rbcL analyses corresponds to the recently described L. lucida from Western Australia, and is a new record for Hawai'i. Hawaiian Halopeltis formed a well-supported clade along with H. adnata from Korea, the recently described H. tanakae from mesophotic depths in Japan, and H. willisii from North Carolina, and is here described as Halopeltis nuahilihilia sp. nov. H. nuahilihilia sp. nov. has a distinctive morphology of narrow vegetative axes that harbor constrictions along their length. The current distribution of H. nuahilihilia includes mesophotic depths around W. Maui, W. Moloka'i, and the island of Hawai'i in the Main Hawaiian Islands. Few reproductive characters were observed because of the small number of specimens available; however, both species are distinct based on phylogeny and morphology. These descriptions further emphasize the Hawaiian mesophotic zone as a location harboring many undescribed species of marine macroalgae.

제주도 남부해역에서 채집된 Bathylagidae (바다빙어목) Lipolagus ochotensis 자어의 한국 첫기록 (First Record of the Eared Blacksmelt, Lipolagus ochotensis (Bathylagidae, Osmeriformes) Larvae from the Southern Coastal Waters of Jejudo Island, Korea)

  • 윤문주;지환성
    • 한국어류학회지
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    • 제35권1호
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    • pp.57-63
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    • 2023
  • 본 연구에서는 2018년 2~3월 제주도 남부해역에서 Bathylagidae에 속하는 Lipolagus ochotensis 자어 4개체(체장 13.4~21.3 mm)를 봉고네트로 채집하였다. L. ochotensis 자어는 몸이 길게 신장되었으며, 체고는 낮고, 눈이 돌출되며, 몸의 후반부에 흑색소포가 나 있고, 등지느러미가 몸 중앙에 위치하는 특징을 가진다. 미토콘드리아 DNA COI의 염기서열 625 bp를 분석한 결과, L. ochotensis 성어와 97.6%로 매우 가깝게 나타났다. 국내 처음 보고되는 본 종의 새로운 과명으로 "심해빙어과", 속명으로 "검은빙어속", 국명으로 "검은뺨빙어"를 각각 제안한다.

Evaluation of porcine intestinal organoids as an in vitro model for mammalian orthoreovirus 3 infection

  • Se-A Lee;Hye Jeong Lee;Na-Yeon Gu;Yu-Ri Park;Eun-Ju Kim;Seok-Jin Kang;Bang-Hun Hyun;Dong-Kun Yang
    • Journal of Veterinary Science
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    • 제24권4호
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    • pp.53.1-53.12
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    • 2023
  • Background: Mammalian orthoreovirus type 3 (MRV3), which is responsible for gastroenteritis in many mammalian species including pigs, has been isolated from piglets with severe diarrhea. However, the use of pig-derived cells as an infection model for swine-MRV3 has rarely been studied. Objectives: This study aims to establish porcine intestinal organoids (PIOs) and examine their susceptibility as an in vitro model for intestinal MRV3 infection. Methods: PIOs were isolated and established from the jejunum of a miniature pig. Established PIOs were characterized using polymerase chain reaction (PCR) and immunofluorescence assays (IFAs) to confirm the expression of small intestine-specific genes and proteins, such as Lgr5, LYZI, Mucin-2, ChgA, and Villin. The monolayered PIOs and three-dimensional (3D) PIOs, obtained through their distribution to expose the apical surface, were infected with MRV3 for 2 h, washed with Dulbecco's phosphate-buffered saline, and observed. Viral infection was confirmed using PCR and IFA. We performed quantitative real-time reverse transcription-PCR to assess changes in viral copy numbers and gene expressions linked to intestinal epithelial genes and antiviral activity. Results: The established PIOs have molecular characteristics of intestinal organoids. Infected PIOs showed delayed proliferation with disruption of structures. In addition, infection with MRV3 altered the gene expression linked to intestinal epithelial cells and antiviral activity, and these effects were observed in both 2D and 3D models. Furthermore, viral copy numbers in the supernatant of both models increased in a time-dependent manner. Conclusions: We suggest that PIOs can be an in vitro model to study the infection mechanism of MRV3 in detail, facilitating pharmaceutical development.

Effect of Elevated Temperature on Physiological and Molecular Responses and Photoassimilate Production of Rice Leaves During Early Seed Development

  • Jung-Il Cho;Yo-Han Yoo;Eun-Ji Kim;Hoejeong Jeong;Jae-Kyeong Baek;Wan-Gyu Sang;Sungyul Chang;Dongwon Kwon
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2022년도 추계학술대회
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    • pp.107-107
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    • 2022
  • The increase in atmospheric temperature due to climate change prolongs the period of exposure to high-temperature environments during rice cultivation. In particular, high-temperature during early seed development greatly affects on the productivity and quality of rice. The high temperature at this time not only affects the transport and distribution of assimilates from leaves to seeds and the accumulation of starch in the seeds, but also affects the leaves, which are the production organs of assimilates, and increases the consumption of assimilation products due to an increase in respiration. Therefore, in this study, rice was grown in temperature gradient chambers(TGC) to analyze the effects of high temperature on physiological responses, assimilate production, and changes in gene expression in rice leaves. Analysis of chlorophyll and sugar contents and RNA-seq experiments were performed using flag leaves collected under normal and elevated temperature conditions, respectively, during the early seed development stage, and then these results were comprehensively discussed.

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Unrecorded species of Korean invertebrates discovered through the project of 'Discovery of Korean Indigenous Species' III

  • Su-Jung Ji;Jongwoo Jung;Sa Heung Kim;Dong-Ha Ahn;Min-Seop Kim;Jeounghee Lee;Hee-Min Yang;Geon Hyuk Lee;Eunjung Nam;Taeseo Park;Anna B. Jost;Huyen T. M. Pham;Jina Park;Joohee Park;Seoyoung Keum;Ivana Karanovic;Tomislav Karanovic;Joong-Ki Park;Chuleui Jung;Gi-Sik Min
    • Journal of Species Research
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    • 제12권4호
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    • pp.341-354
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    • 2023
  • This is the third series of catalogs reporting on Korean species discovered through the 'Discovery of Korean Indigenous Species'. This catalog includes 22 species of invertebrates, excluding insects. The catalog includes the scientific name, an abridged list of synonyms, collection sites, distribution, diagnosis, and figures for each species. Additionally, we provide the newly assigned Korean name, specimen voucher, and, if available, mitochondrial CO1 or 16S gene sequences of the species listed. All species identified and documented here will be officially listed on the 'National Species List of Korea', a database maintained by the National Institute of Biological Resources(NIBR).

파킨슨병 변증 유형 및 지표 분포에 대한 전향적 다기관 관찰연구 프로토콜 (An Observational Multi-Center Study Protocol for Distribution of Pattern Identification and Clinical Index in Parkinson's Disease)

  • 조혜연;권오진;서복남;박성욱;유호룡;장정희
    • 대한한방내과학회지
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    • 제45권1호
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    • pp.1-10
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    • 2024
  • Objectives: This study investigated the pattern identification (PI) and clinical index of Parkinson's disease (PD) for personalized diagnosis and treatment. Methods: This prospective observational multi-center study recruited 100 patients diagnosed with PD from two Korean medicine hospitals. To cluster new subtypes of PD, items on a PI questionnaire (heat and cold, deficiency and excess, visceral PI) were evaluated along with pulse and tongue analysis. Gait analysis was performed and blood and feces molecular signature changes were assessed to explore biomarkers for new subtypes. In addition, unified PD rating scale II and III scores and the European quality of life 5-dimension questionnaire were assessed. Results: The clinical index obtained in this study analyzed the frequency statistics and hierarchical clustering analysis to classify new subtypes based on PI. Moreover, the biomarkers and current status of herbal medicine treatment were analyzed using the new subtypes. The results provide comprehensive data to investigate new subtypes and subtype-based biomarkers for the personalized diagnosis and treatment of PD patients. Ethical approval was obtained from the medical ethics committees of the two Korean medicine hospitals. All amendments to the research protocol were submitted and approved. Conclusions: An objective and standardized diagnostic tool is needed for the personalized treatment of PD by traditional Korean medicine. Therefore, we developed a clinical index as the basis for the PI clinical evaluation of PD. Trial Registration: This trial is registered with the Clinical Research Information Service (CRIS) (KCT0008677)

Research progress on hydrogel-based drug therapy in melanoma immunotherapy

  • Wei He;Yanqin Zhang;Yi Qu;Mengmeng Liu;Guodong Li;Luxiang Pan;Xinyao Xu;Gege Shi;Qiang Hao;Fen Liu;Yuan Gao
    • BMB Reports
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    • 제57권2호
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    • pp.71-78
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    • 2024
  • Melanoma is one of the most aggressive skin tumors, and conventional treatment modalities are not effective in treating advanced melanoma. Although immunotherapy is an effective treatment for melanoma, it has disadvantages, such as a poor response rate and serious systemic immune-related toxic side effects. The main solution to this problem is the use of biological materials such as hydrogels to reduce these side effects and amplify the immune killing effect against tumor cells. Hydrogels have great advantages as local slow-release drug carriers, including the ability to deliver antitumor drugs directly to the tumor site, enhance the local drug concentration in tumor tissue, reduce systemic drug distribution and exhibit good degradability. Despite these advantages, there has been limited research on the application of hydrogels in melanoma treatment. Therefore, this article provides a comprehensive review of the potential application of hydrogels in melanoma immunotherapy. Hydrogels can serve as carriers for sustained drug delivery, enabling the targeted and localized delivery of drugs with minimal systemic side effects. This approach has the potential to improve the efficacy of immunotherapy for melanoma. Thus, the use of hydrogels as drug delivery vehicles for melanoma immunotherapy has great potential and warrants further exploration.