• Title/Summary/Keyword: migration process

Search Result 543, Processing Time 0.03 seconds

Improvement of Electrochemical Performance of Lithium-ion Secondary Batteries using Double-Layered Thick Cathode Electrodes

  • Phiri, Isheunesu;Kim, Jeong-Tae;Kennedy, Ssendagire;Ravi, Muchakayala;Lee, Yong Min;Ryou, Myung-Hyun
    • Journal of the Korean Electrochemical Society
    • /
    • v.25 no.1
    • /
    • pp.32-41
    • /
    • 2022
  • Various steps in the electrode production process, such as slurry mixing, slurry coating, drying, and calendaring, directly affect the quality and, consequently, mechanical properties and electrochemical performance of electrodes. Herein, a new method of slurry coating is developed: Double-coated electrode. Contrary to single-coated electrode, the cathode is prepared by double coating, wherein each coat is of half the total loading mass of the single-coated electrode. Each coat is dried and calendared. It is found that the double-coated electrode possesses more uniform pore distribution and higher electrode density and allows lesser extent of particle segregation than the single-coated electrode. Consequently, the double-coated electrode exhibits higher adhesion strength (74.7 N m-1) than the single-coated electrode (57.8 N m-1). Moreover, the double-coated electrode exhibits lower electric resistance (0.152 Ω cm-2) than the single-coated electrode (0.177 Ω cm-2). Compared to the single-coated electrode, the double-coated electrode displays higher electrochemical performance by exhibiting better rate capability, especially at higher C rates, and higher long-term cycling performance. Despite its simplicity, the proposed method allows effective electrode preparation by facilitating high electrochemical performance and is applicable for the large-scale production of high-energy-density electrodes.

In vivo molecular and single cell imaging

  • Hong, Seongje;Rhee, Siyeon;Jung, Kyung Oh
    • BMB Reports
    • /
    • v.55 no.6
    • /
    • pp.267-274
    • /
    • 2022
  • Molecular imaging is used to improve the disease diagnosis, prognosis, monitoring of treatment in living subjects. Numerous molecular targets have been developed for various cellular and molecular processes in genetic, metabolic, proteomic, and cellular biologic level. Molecular imaging modalities such as Optical Imaging, Magnetic Resonance Imaging (MRI), Positron Emission Tomography (PET), Single Photon Emission Computed Tomography (SPECT), and Computed Tomography (CT) can be used to visualize anatomic, genetic, biochemical, and physiologic changes in vivo. For in vivo cell imaging, certain cells such as cancer cells, immune cells, stem cells could be labeled by direct and indirect labeling methods to monitor cell migration, cell activity, and cell effects in cell-based therapy. In case of cancer, it could be used to investigate biological processes such as cancer metastasis and to analyze the drug treatment process. In addition, transplanted stem cells and immune cells in cell-based therapy could be visualized and tracked to confirm the fate, activity, and function of cells. In conventional molecular imaging, cells can be monitored in vivo in bulk non-invasively with optical imaging, MRI, PET, and SPECT imaging. However, single cell imaging in vivo has been a great challenge due to an extremely high sensitive detection of single cell. Recently, there has been great attention for in vivo single cell imaging due to the development of single cell study. In vivo single imaging could analyze the survival or death, movement direction, and characteristics of a single cell in live subjects. In this article, we reviewed basic principle of in vivo molecular imaging and introduced recent studies for in vivo single cell imaging based on the concept of in vivo molecular imaging.

Bioremediation Options for Nuclear Sites a Review of an Emerging Technology

  • Robinson, Callum;White-Pettigrew, Matthew;Shaw, Samuel;Morris, Katherine;Graham, James;Lloyd, Jonathan R.
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.20 no.3
    • /
    • pp.307-319
    • /
    • 2022
  • 60+ Years of nuclear power generation has led to a significant legacy of radioactively contaminated land at a number of nuclear licenced "mega sites" around the world. The safe management and remediation of these sites is key to ensuring there environmental stewardship in the long term. Bioremediation utilizes a variety of microbially mediated processes such as, enzymatically driven metal reduction or biominerialisation, to sequester radioactive contaminants from the subsurface limiting their migration through the geosphere. Additionally, some of these process can provide environmentally stable sinks for radioactive contaminants, through formation of highly insoluble mineral phases such as calcium phosphates and carbonates, which can incorporate a range of radionuclides into their structure. Bioremediation options have been considered and deployed in preference to conventional remediation techniques at a number of nuclear "mega" sites. Here, we review the applications of bioremediation technologies at three key nuclear licenced sites; Rifle and Hanford, USA and Sellafield, UK, in the remediation of radioactively contaminated land.

Ginsenoside Re inhibits myocardial fibrosis by regulating miR-489/myd88/NF-κB pathway

  • Jinghui Sun;Ru Wang;Tiantian Chao;Jun Peng;Chenglong Wang;Keji Chen
    • Journal of Ginseng Research
    • /
    • v.47 no.2
    • /
    • pp.218-227
    • /
    • 2023
  • Background: Myocardial fibrosis (MF) is an advanced pathological manifestation of many cardiovascular diseases, which can induce heart failure and malignant arrhythmias. However, the current treatment of MF lacks specific drugs. Ginsenoside Re has anti-MF effect in rat, but its mechanism is still not clear. Therefore, we investigated the anti-MF effect of ginsenoside Re by constructing mouse acute myocardial infarction (AMI) model and AngII induced cardiac fibroblasts (CFs) model. Methods: The anti-MF effect of miR-489 was investigated by transfection of miR-489 mimic and inhibitor in CFs. Effect of ginsenoside Re on MF and its related mechanisms were investigated by ultrasonographic, ELISA, histopathologic staining, transwell test, immunofluorescence, Western blot and qPCR in the mouse model of AMI and the AngII-induced CFs model. Results: MiR-489 decreased the expression of α-SMA, collagenI, collagen III and myd88, and inhibited the phosphorylation of NF-κB p65 in normal CFs and CFs treated with AngII. Ginsenoside Re could improve cardiac function, inhibit collagen deposition and CFs migration, promote the transcription of miR-489, and reduce the expression of myd88 and the phosphorylation of NF-κB p65. Conclusion: MiR-489 can effectively inhibit the pathological process of MF, and the mechanism is at least partly related to the regulation of myd88/NF-κB pathway. Ginsenoside Re can ameliorate AMI and AngII induced MF, and the mechanism is at least partially related to the regulation of miR-489/myd88/NF-κB signaling pathway. Therefore, miR-489 may be a potential target of anti-MF and ginsenoside Re may be an effective drug for the treatment of MF.

A Study on the Development and Performance Improvement of Chatbot for Office Automation (행정업무 자동화 챗봇 개발 및 성능 향상에 관한 연구)

  • Park, Junsoo;Kim, Youngjun;Jung, Yoonkyo
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2022.05a
    • /
    • pp.158-160
    • /
    • 2022
  • Many office workers spend a lot of time performing repetitive office tasks in inefficient ways. We developed a user-friendly chatbot system based on Kakaotalk to automate repetitive tasks and used the chatbot in the real workplace. In the process of operating the chatbot, if several people use the chatbot at the same time, the server was down or could not respond. To address these issues, we performed code migration of programs used by chatbot back-end servers and tried several ways to improve server performance such as database redesign and load balancing. To determine how much each method affects performance improvement, we measured total request per second and average latency. After that, we proposed ways to improve the problems of using the chatbot in the work environment.

  • PDF

A Study on Sustainable Greenspace based on Urban Remodeling Design of an Old Apartment Building

  • Myung Sik Lee;Seung Ryeol Min
    • International Journal of High-Rise Buildings
    • /
    • v.12 no.2
    • /
    • pp.179-193
    • /
    • 2023
  • It is undeniable that urban greenspace is the soul of a city. Conventional urban greenspace such as parks, community gardens, playgrounds etc. located within a city reduce the negative effects of pollution, play a major role in the survival of the urban ecosystem, and promote healthy lifestyles. Today, 55% of the world's population lives in urban areas, which is expected to increase to 68% by 2050. Projections show that urbanization and the gradual migration to urban areas combined with the fast growth of the world's population, could add another 2.5 billion people to urban areas by 2050 and almost 90% of this increase will take place in Asia(UN, 2018). As a result, many plots in the cities are and will continue to be occupied with buildings to provide residential support to the increased population. This will dangerously decrease urban greenspaces. Moreover, worldwide, food crisis, energy crisis, and social crisis is posing a great threat to the existence of mankind. Additionally, the COVID - 19 has introduced a new lifestyle where from work culture to community configuration has drastically transformed. In this scenario, residential buildings will have to serve more than just providing privacy and shelter. As urban greenspaces are being occupied by concrete residential buildings, these buildings will have to compensate for the percentage of urban green they are destroying and the issues they are imposing in the process. The goal of this thesis is to design, architecturally define and, categorize comprehensive 'sustainable Greenspace'(S.G.S) for the multi-family housing scenario. These will be different than the conventional green (veranda, rooftop green) we commonly see in residential buildings. An old, dilapidated apartment building will be the target of remodeling to fulfill the purpose of this thesis.

Unveiling the impact of lysosomal ion channels: balancing ion signaling and disease pathogenesis

  • Yoona Jung;Wonjoon Kim;Na Kyoung Shin;Young Min Bae;Jinhong Wie
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.27 no.4
    • /
    • pp.311-323
    • /
    • 2023
  • Ion homeostasis, which is regulated by ion channels, is crucial for intracellular signaling. These channels are involved in diverse signaling pathways, including cell proliferation, migration, and intracellular calcium dynamics. Consequently, ion channel dysfunction can lead to various diseases. In addition, these channels are present in the plasma membrane and intracellular organelles. However, our understanding of the function of intracellular organellar ion channels is limited. Recent advancements in electrophysiological techniques have enabled us to record ion channels within intracellular organelles and thus learn more about their functions. Autophagy is a vital process of intracellular protein degradation that facilitates the breakdown of aged, unnecessary, and harmful proteins into their amino acid residues. Lysosomes, which were previously considered protein-degrading garbage boxes, are now recognized as crucial intracellular sensors that play significant roles in normal signaling and disease pathogenesis. Lysosomes participate in various processes, including digestion, recycling, exocytosis, calcium signaling, nutrient sensing, and wound repair, highlighting the importance of ion channels in these signaling pathways. This review focuses on different lysosomal ion channels, including those associated with diseases, and provides insights into their cellular functions. By summarizing the existing knowledge and literature, this review emphasizes the need for further research in this field. Ultimately, this study aims to provide novel perspectives on the regulation of lysosomal ion channels and the significance of ion-associated signaling in intracellular functions to develop innovative therapeutic targets for rare and lysosomal storage diseases.

The Betrayal of Love, Trauma Narrative and Subjectivity Formation: Toni Morrison's A Mercy (사랑의 배반, 트라우마 서사와 주체 형성 -토니 모리슨의 『자비』)

  • Koo, Eunsook
    • Journal of English Language & Literature
    • /
    • v.57 no.5
    • /
    • pp.813-838
    • /
    • 2011
  • Toni Morrison's ninth novel A Mercy delves into the colonial American history of the seventeenth century when Europeans began to migrate to the New World and when the first slaves were brought to Virginia. Morrison presents a diverse group of people such as white Europeans, an American Indian, a free black man, indentured servants, and slaves from Africa in order to explore the subjects of ownership, freedom and racism. She emphasizes the fact that most of the Europeans who came to America in the early seventeenth century were the people who were thrown out from the society such as felons, prostitutes, servants and children. By portraying how these castaways tried to settle in a new environment surrounded by unknown dangers and challenges, Morrison demystifies and reconstructs the myth of the birth of America as a nation state. In continuation of Morrison's writings about love and the betrayal of love, her novel A Mercy explores the subjects of trauma, memory and subjectivity by choosing the topic of motherly love and its betrayal which she dealt with poignantly in Beloved. The female protagonist, Florens, is given away by her mother in partial payment of debt incurred by the owner of Florens's mother. The traumatic memory of Florens's separation from her mother shapes Florence's character. She has to revisit the site of the original traumatic experiences of being given up by her mother in order to reconstruct her fragmented memory and past. The recurring dream of the traumatic incident that takes hold of Florens can be explained by the trauma theory of Freud, Cathy Caruth, Suzette Henke, and Judith Herman. The paper explores the self journey of Florens in which she faces the traumatic past and comprehends its meaning which enables her to construct her subjectivity by understanding the true meaning of being free and of owning oneself. In particular, it demonstrates how the process of writing a confession, a story about one's history, enables one to reclaim the traumatic experience and to locate it in the narrative memory.

Anti-photoaging and anti-oxidative activities of natural killer cell conditioned medium following UV-B irradiation of human dermal fibroblasts and a reconstructed skin model

  • Sung‑Eun Lee;Tae‑Rin Kwon;Jong Hwan Kim;Byung‑Chul Lee;Chang Taek Oh;Minju Im;Kyeong Hwang;Sang Hoon Paik;Seungryel Han;Jeom‑Yong Kim;Beom Joon Kim
    • International Journal of Molecular Medicine
    • /
    • v.44 no.5
    • /
    • pp.1641-1652
    • /
    • 2019
  • Conditioned media from various sources comprise numerous growth factors and cytokines and are known to promote the regeneration of damaged tissues. Among these, natural killer cell conditioned medium (NK-CdM) has been shown to stimulate collagen synthesis and the migration of fibroblasts during the wound healing process. With a long-term aim of developing a treatment for skin photoaging, the ability of NK-CdM to prevent ultraviolet-B (UV-B) damage was assessed in neonatal human dermal fibroblasts (NHDFs) and an in vitro reconstructed skin model. The factors present in NK-CdM were profiled using an antibody array analysis. Protein and mRNA levels in UV-B exposed NHDFs treated with NK-CdM were measured by western blotting and quantitative reverse transcription-PCR, respectively. The total antioxidant capacity of NK-CdM was determined to assess its ability to suppress reactive oxygen species. The anti-photoaging effect of NK-CdM was also assessed in a 3D reconstituted human full skin model. NK-CdM induced proliferation of UV-B-treated NHDFs, increased procollagen expression, and decreased matrix metalloproteinase (MMP)-1 expression. NK-CdM also exhibited a potent antioxidant activity as measured by the total antioxidant capacity. NK-CdM inhibited UV-B-induced collagen degradation by inactivating MAPK signaling. NK-CdM also elicited potential anti-wrinkle effects by inhibiting the UV-B-induced increase in MMP-1 expression levels in a 3D reconstituted human full skin model. Taken together, the suppression of both UV-B-induced MMP-1 expression and JNK activation by NK-CdM suggests NK-CdM as a possible candidate anti-skin aging agent.

Electrical properties of metal-oxide-semiconductor structures containing Si nanocrystals fabricated by rapid thermal oxidation process (급속열처리산화법으로 형성시킨 $SiO_2$/나노결정 Si의 전기적 특성 연구)

  • Kim, Yong;Park, Kyung-Hwa;Jung, Tae-Hoon;Park, Hong-Jun;Lee, Jae-Yeol;Choi, Won-Chul;Kim, Eun-Kyu
    • Journal of the Korean Vacuum Society
    • /
    • v.10 no.1
    • /
    • pp.44-50
    • /
    • 2001
  • Metal oxide semiconductor (MOS) structures containing nanocrystals are fabricated by using rapid thermal oxidations of amorphous silicon films. The amorphous films are deposited either by electron beam deposition method or by electron beam deposition assisted by Ar ion beam during deposition. Post oxidation of e-beam deposited film results in relatively small hysteresis of capacitance-voltage (C-V) and the flat band voltage shift, $\DeltaV_{FB}$ is less than 1V indicative of the formation of low density nanocrystals in $SiO_2$ near $SiO_2$/Si interface. By contrast, we observe very large hysteresis in C-V characteristics for oxidized ion-beam assisted e-beam deposited sample. The flat band voltage shift is larger than 22V and the hysteresis becomes even broader as increasing injection times of holes at accumulation condition and electrons at inversion condition. The result indicates the formation of slow traps in $SiO_2$ near $SiO_2$/Si interface which might be related to large density nanocrystals. Roughly estimated trap density is $1{\times}10^{13}cm^{-2}$. Such a large hysteresis may be explained in terms of the activation of adatom migration by Ar ion during deposition. The activated migration may increase nucleation rate of Si nuclei in amorphous Si matrix. During post oxidation process, nuclei grow into nanocrystals. Therefore, ion beam assistance during deposition may be very feasible for MOS structure containing nanocrystals with large density which is a basic building block for single electron memory device.

  • PDF