• 제목/요약/키워드: functional role

검색결과 1,957건 처리시간 0.032초

Enhanced binding between metals and CNT surface mediated by oxygen

  • 박미나;김병현;이광렬
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
    • /
    • pp.61-61
    • /
    • 2010
  • In the present work, we present the optimized the hybrid structures of carbon nanotubes (CNTs) and metal nanocomposites including Cu, Al, Co and Ni using the first principle calculations based on the density functional theory. Introduction of CNTs into a metal matrix has been considered to improve the mechanical properties of the metal matrix. However, the binding energy between metals and pristine CNTs wall is known to be so small that the interfacial slip between CNTs and the matrix occurs at a relatively low external stress. The application of defective or functionalized CNTs has thus attracted great attention to enhance the interfacial strength of CNT/metal nanocomposites. Herein, we design the various hybrid structures of the single wall CNT/metal complexes and characterize the interaction between single wall CNTs and various metals such as Cu, Al, Co or Ni. First, differences in the binding energies or electronic structures of the CNT/metal complexes with the topological defects, such as the Stone-Wales and vacancy, are compared. Second, the characteristics of functionalized CNTs with various surface functional groups, such as -O, -COOH, -OH interacting with metals are investigated.We found that the binding energy can be enhanced by the surface functional group including oxygen since the oxygen atom can mediate and reinforce the interaction between carbon and metal. The binding energy is also greatly increased when it is absorbed on the defects of CNTs. These results strongly support the recent experimental work which suggested the oxygen on the interface playing an important role in the excellent mechanical properties of the CNT-Cu composite[1].

  • PDF

Comparative analysis of dietary exosome-derived microRNAs from human, bovine and caprine colostrum and mature milk

  • Yun, Bohyun;Kim, Younghoon;Park, Dong June;Oh, Sangnam
    • Journal of Animal Science and Technology
    • /
    • 제63권3호
    • /
    • pp.593-602
    • /
    • 2021
  • Mammalian milk including microRNAs (miRNAs) as a novel class of noncoding RNAs, that can be transferred to infants and it plays on a critical role in biological functions such as immune regulation and development. However, the origin and functional importance of milk-derived miRNAs are still undetermined. This study applied RNA sequencing to explore the featured profiles of miRNA expression in colostrum and mature milk-originated exosomes from human, bovine, and caprine milk. These dietary exosome-derived miRNAs are highly conserved in human, bovine and caprine milk. Interestingly, abundant miRNAs expressed in human milk are similarly conserved across species. In addition, we confirmed that immune-related miRNAs (miR-30a-5p, miR-22-3p, and miR-26a) are commonly observed in the colostrum and mature milk of cows and caprines as well as humans. Our results provide new insights and resources for investigating the functionality of immune-associated miRNAs and evaluating physiological and biological condition in human, bovine and caprine milk as biomarkers.

Mini-review: oomycete RXLR genes as effector-triggered immunity

  • Arif, Saima;Jang, Hyun A;Kim, Mi-Reu;Oh, Sang-Keun
    • 농업과학연구
    • /
    • 제45권4호
    • /
    • pp.561-573
    • /
    • 2018
  • Oomycetes are known to secrete a vast arsenal of effectors that modulate the host defense system as well as facilitate establishing a parasitic infection in plants. In recent years, tremendous progress has been made in the field of effectromics based on studies of oomycetes, especially the cytoplasmic family of RXLR effectors. Yet, the biology of the RXLR effector family is still poorly understood. There has been a consensus regarding the structure of the RXLR motif in the mycologist community. However, the function of the RXLR motif is still unclear. First, different models have suggested that the role of the RXLR motif is either in translocation to a target destination inside a host cell or in the cleavage of itself followed by secretion. Second, recent studies have suggested different functional models for the RXLR motif. According to a widely accepted model, the RXLR motif is directly involved in the translocation of effectors to target sites. In contrast, a new study has proposed that the RXLR motif is involved in secretion rather than translocation. Thus, this review is an attempt to summarize the recent advances made in the functional analysis of the N-terminal domain of RXLR effectors.

기능에서 상징으로: 평양역사 건설, 1907-1958 (From the Functional to the Monumental: The Construction of the Pyongyang Station, 1907-1958)

  • 박동민
    • 대한건축학회논문집:계획계
    • /
    • 제35권4호
    • /
    • pp.115-126
    • /
    • 2019
  • Construction of the Pyongyang Railroad Station began in 1907 as an important foothold for the Japanese colonization of the Korean Peninsula and the further invasion of Manchuria. As Pyongyang gradually grew in size and political significance, the Pyongyang Station came to have two responsibilities: Fulfill its functional role and serve as a monument to the growing dignity of the city. This study argues that the Pyongyang Station, newly rebuilt in 1958, was the first building to solve the demands for both functional expansion and the pursuit of monumentality. Stylistically, the original single-story wooden building became a three-story classical masonry building. The stylistic change symbolizes the political shift by which the building was reconstructed. The simple wooden building built by the Japanese, representing Pyongyang's status as a colonial provincial town, was transformed into an imposing gateway for the capital city of a newly born socialist state. Socialist Realism, correctly described by its slogan "socialist in content and national in form," harmoniously blended classical architecture, socialist symbols, and Korean local motifs. This study is significant in that it illustrates the historical changes and continuity of the Pyongyang Station from 1907, when it was first built, through the "liberated space" to the postwar reconstruction period of the 1950s.

Effects of a Low-Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyol Diet on Symptoms of Functional Abdominal Pain in Pediatric Patients

  • Gendy, Yasmine Gamal Abdou El;Wahed, Mohammad Ashraf Abdel;Ragab, Mostafa Hussein Hassan;Awad, Yosra Mohamed Mohsen
    • Pediatric Gastroenterology, Hepatology & Nutrition
    • /
    • 제25권6호
    • /
    • pp.510-518
    • /
    • 2022
  • Purpose: Recently, great interest has been focused on dietary fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) for the treatment of functional abdominal pain (FAP). Several meta-analyses, including those on the adult population, have been published, potentiating its role. However, pediatric studies are scarce. We aimed to evaluate the effect of a low-FODMAP diet on the severity of FAP in children. Methods: This clinical trial included 50 patients aged 3-18 years with irritable bowel syndrome and FAP that were not otherwise specified. The patients were instructed to receive a low FODMAP diet guided by a dietitian. The primary outcome was the percentage of responders after 2 months of dietary intervention compared with baseline. Other outcomes included changes in stool consistency and quality of life (QoL) scores using the KIDSCREEN-10 questionnaire, and weight-for-age z-scores. Results: After the dietary intervention, 74% of patients showed more than 30% lower pain intensity, as examined using the Wong-Baker Faces pain rating scale. Their QoL significantly improved, and patients have gained weight. Conclusion: A low FODMAP diet can improve pain intensity and QoL among children with functional abdominal pain, with no detrimental effects on body weight.

Mitochondrial transplantation: an overview of a promising therapeutic approach

  • Ji Soo Kim;Seonha Lee;Won-Kon Kim;Baek-Soo Han
    • BMB Reports
    • /
    • 제56권9호
    • /
    • pp.488-495
    • /
    • 2023
  • Mitochondrial transplantation is a promising therapeutic approach for the treatment of mitochondrial diseases caused by mutations in mitochondrial DNA, as well as several metabolic and neurological disorders. Animal studies have shown that mitochondrial transplantation can improve cellular energy metabolism, restore mitochondrial function, and prevent cell death. However, challenges need to be addressed, such as the delivery of functional mitochondria to the correct cells in the body, and the long-term stability and function of the transplanted mitochondria. Researchers are exploring new methods for mitochondrial transplantation, including the use of nanoparticles or CRISPR gene editing. Mechanisms underlying the integration and function of transplanted mitochondria are complex and not fully understood, but research has revealed some key factors that play a role. While the safety and efficacy of mitochondrial transplantation have been investigated in animal models and human trials, more research is needed to optimize delivery methods and evaluate long-term safety and efficacy. Clinical trials using mitochondrial transplantation have shown mixed results, highlighting the need for further research in this area. In conclusion, although mitochondrial transplantation holds significant potential for the treatment of various diseases, more work is needed to overcome challenges and evaluate its safety and efficacy in human trials.

Globalization, Family life, and the Future Research Environment in Home Economics and Human Sciences

  • Jim, Moran
    • International Journal of Human Ecology
    • /
    • 제4권2호
    • /
    • pp.89-100
    • /
    • 2003
  • This paper identifies trends in research methodology due to globalization. Context in both research and in practice and forms the key perspective for modern methodology and theory. Ecological perspectives are a necessary condition for quality global research. Human ecology researchers must advance the role of interdisciplinary and inter-functional perspectives and be open to collaborative relationships. These researchers must work in teams across disciplinary and functional boundaries. The paper discusses directions for research within the context of trends at U.S. federal agencies with applications to globalization and family life. Trends include: (a) use of diverse but rigorous methodologies; (b) recognition of the research-practice-research feedback loop;(c) primacy of context and diverse sampling; and (d) connections of research to problem solving. The terms promoted recently such as ″relationships″, ″diversity″ or ″problem-based″ are ingrained in human ecology. Key aspects for research in the next decade will be: (a) seeking diversity in sampling; (b) seeking colleagues with different perspectives; (c) incorporating meta-analysis into our work; (d) seeking meaningful results; (e) utilizing varieties of research methodologies to address our problems; and (0 understanding that practice must continually change as a function of research.

Functional Changes of Spinal Sensory Neurons Following Gray Matter Degeneration

  • Park, Sah-Hoon;Park, Jong-Seong;Jeong, Han-Seong
    • The Korean Journal of Physiology
    • /
    • 제30권2호
    • /
    • pp.289-297
    • /
    • 1996
  • Excitatory amino acids (EAA) are thought to play an important role in producing cell death associated with ischemic and traumatic spinal cord injury. The present study was carried out to determine if the response characteristics of spinal sensory neurons in segments adjacent to degeneration sites induced by EAA are altered following these morphological changes. Intraspinal injections of quisqualic acid (QA) produced neuronal degeneration and spinal cavitation of gray matter. The severity of lesions was significantly attenuated by pretreatment with a non-NMDA antagonist NBQX. In extracellular single unit recordings, dorsal horn neurons in QA injected animal showed the increased mechanosensitivity, which included a shift to the left in the stimulus-response relationship, an increased background activity and an increase in the duration of after-discharge responses. Neuronal responses, especially the C-fiber response, to suprathreshold electrical stimulation of sciatic nerve also increased in most cases. These results suggest that altered functional states of neurons may be responsible for sensory abnormalities, e.g. allodynia and hyperalgesia, associated with syringomyolia and spinal cord injury.

  • PDF

Long non-coding RNA linc00152 acting as a promising oncogene in cancer progression

  • Seo, Danbi;Kim, Dain;Kim, Wanyeon
    • Genomics & Informatics
    • /
    • 제17권4호
    • /
    • pp.36.1-36.6
    • /
    • 2019
  • The incidence and mortality rate of cancer continues to gradually increase, although considerable research effort has been directed at elucidating the molecular mechanisms underlying biomarkers responsible for tumorigenesis. Accumulated evidence indicates that the long non-coding RNAs (lncRNAs), which are transcribed but not translated into functional proteins, contribute to cancer development. Recently, linc00152 (an lncRNA) was identified as a potent oncogene in various cancer types, and shown to be involved in cancer cell proliferation, invasiveness, and motility by sponging tumor-suppressive microRNAs acting as a competing endogenous RNA, binding to gene promoters acting as a transcriptional regulator, and binding to functional proteins. In this review, we focus on the oncogenic role of linc00152 in tumorigenesis and provided an overview of recent clinical studies on the effects of linc00152 expression in human cancers.

작용기를 치환한 Metal-Organic Frameworks 에 대한 DFT 연구 (A Density Functional Theory Study on a Series of Functionalized Metal-Organic Frameworks)

  • 김대진;이태범;최승훈;이은성;오유진;윤지혜;김자헌
    • 한국전기화학회:학술대회논문집
    • /
    • 한국전기화학회 2005년도 수소연료전지공동심포지움 2005논문집
    • /
    • pp.329-334
    • /
    • 2005
  • In order to find out rational design and synthetic strategies toward efficient hydrogen storage materials, we performed quantum mechanical calculations on a series of the Metal-Organic Frameworks (MOFs) containing functionalized organic linkers. Based on the shape of frontier orbitals and the electrostatic potential map of various MOFs from density functional theory calculations, it was found that the delocalization of electron and asymmetric polarization of the organic linker play an important role in the hydrogen storage capacity of Metal-Organic Frameworks. The prediction of the modeling study could be supported by the hydrogen adsorption experiments using MOF-5 and amine substituted MOF-5, which showed more enhanced hydrogen storage capacity of amine substituted MOF-5 compared with that of MOF-5.

  • PDF