• Title/Summary/Keyword: Response efficacy

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Experimental Study on the Active Control of a Three-story Building using $\textrm{H}_2$method ($\textrm{H}_2$제어 기법을 적용한 3층 건물의 능동제어 실험)

  • Joo, Soek-Jun;Min, Kyung-Won;Lee, Sung-Kyung;Kim, Sung-Chon;Hong, Sung-Mok
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1999.10a
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    • pp.225-232
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    • 1999
  • For the study of the seismic-response control, it is necessary to use an experimental system with an earthquake simulator and control devices employing a hydraulic actuator system. However, such system is too expensive to prepare at the university laboratory. In this research, an economical experimental system is developed which has a small-sized earthquake simulator and an AMD using AC servo motors. An accurate mathematical model of the three-degree-of-freedom tests structure with an AMD is developed from the measurement of the input/output relationships of the structure. This paper demonstrates experimentally the efficacy of the frequency domain optimal control algorithm H$_2$in reducing the response of seismically excited building to verify the performance of the experimental system.

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Experimental Study on the Vibration Control for Building Structures using LQG Compensator (LQG 보상기를 이용한 건물의 진동제어 실험)

  • 민경원
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 1999.04a
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    • pp.202-216
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    • 1999
  • To control the motion of building structures under earthquakes their response should be measured first by various sensors and transformed into the control forces using some control algorithms. Of many control algorithms linear quadratic control is widely used as it is easy to implement and analyze. However the algorithms has the disadvantage that it needs the real-time measurements of all state variables(i.e, building's displacements and velocities) which are difficult to achieve for the building structures under earthquakes. Thus the practical algorithms employing output feedback are developed. In this paper LQG algorithm is used for the control of the building model with an active mass driver. The building's acceleration is used to obtain the control gain and the Kalman filter gain. The LQG control strategy is verified with the experimental study on the one-storybuilding model equipped with the active mass driver. This paper demonstrates experimentally the efficacy of the LQG algorithm based on the active mass driver system in reducing the response of seismically excited buildings.

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Cellular senescence: a promising strategy for cancer therapy

  • Lee, Seongju;Lee, Jae-Seon
    • BMB Reports
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    • v.52 no.1
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    • pp.35-41
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    • 2019
  • Cellular senescence, a permanent state of cell cycle arrest, is believed to have originally evolved to limit the proliferation of old or damaged cells. However, it has been recently shown that cellular senescence is a physiological and pathological program contributing to embryogenesis, immune response, and wound repair, as well as aging and age-related diseases. Unlike replicative senescence associated with telomere attrition, premature senescence rapidly occurs in response to various intrinsic and extrinsic insults. Thus, cellular senescence has also been considered suppressive mechanism of tumorigenesis. Current studies have revealed that therapy-induced senescence (TIS), a type of senescence caused by traditional cancer therapy, could play a critical role in cancer treatment. In this review, we outline the key features and the molecular pathways of cellular senescence. Better understanding of cellular senescence will provide insights into the development of powerful strategies to control cellular senescence for therapeutic benefit. Lastly, we discuss existing strategies for the induction of cancer cell senescence to improve efficacy of anticancer therapy.

Security Determinants of the Educational Use of Mobile Cloud Computing in Higher Education

  • Waleed Alghaith
    • International Journal of Computer Science & Network Security
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    • v.24 no.9
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    • pp.50-62
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    • 2024
  • The decision to integrate mobile cloud computing (MCC) in higher education without first defining suitable usage scenarios is a global issue as the usage of such services becomes extensive. Consequently, this study investigates the security determinants of the educational use of mobile cloud computing among universities' students. This study proposes and develops a theoretical model by adopting and modifying the Protection Motivation Theory (PMT). The study's findings show that a significant amount of variance in MCC adoption was explained by the proposed model. MCC adoption intention was shown to be highly influenced by threat appraisal and coping appraisal factors. Perceived severity alone explains 37.8% of students "Intention" to adopt MCC applications, which indicates the student's perception of the degree of harm that would happen can hinder them from using MCC. It encompasses concerns about data security, privacy breaches, and academic integrity issues. Response cost, perceived vulnerability and response efficacy also have significant influence on students "intention" by 18.8%, 17.7%, and 6.7%, respectively.

Security Determinants of the Educational Use of Mobile Cloud Computing in Higher Education

  • Waleed Alghaith
    • International Journal of Computer Science & Network Security
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    • v.24 no.8
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    • pp.105-118
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    • 2024
  • The decision to integrate mobile cloud computing (MCC) in higher education without first defining suitable usage scenarios is a global issue as the usage of such services becomes extensive. Consequently, this study investigates the security determinants of the educational use of mobile cloud computing among universities students. This study proposes and develops a theoretical model by adopting and modifying the Protection Motivation Theory (PMT). The studys findings show that a significant amount of variance in MCC adoption was explained by the proposed model. MCC adoption intention was shown to be highly influenced by threat appraisal and coping appraisal factors. Perceived severity alone explains 37.8% of students "Intention" to adopt MCC applications, which indicates the student's perception of the degree of harm that would happen can hinder them from using MCC. It encompasses concerns about data security, privacy breaches, and academic integrity issues. Response cost, perceived vulnerability and response efficacy also have significant influence on students "intention" by 18.8%, 17.7%, and 6.7%, respectively.

Clinical Course of Infliximab Treatment in Korean Pediatric Ulcerative Colitis Patients: A Single Center Experience

  • Kim, Jong Min;Lee, Yoo Min;Kang, Ben;Choe, Yon Ho
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.17 no.1
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    • pp.31-36
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    • 2014
  • Purpose: Infliximab (IFX) is considered safe and effective for the treatment of ulcerative colitis (UC) in both adults and children. The aim of this study was to evaluate the short- and long-term clinical course of IFX in Korean children with UC. Methods: Pediatric patients with UC who had received IFX infusions between November 2007 and May 2013 at Samsung Medical Center were retrospectively investigated. The clinical efficacy of IFX treatment was evaluated at 8 weeks (short term) and 54 weeks (long term) after the initiation of IFX treatment using the Pediatric Ulcerative Colitis Activity Index (PUCAI). The degree of response to IFX treatment was defined as complete response (PUCAI score=0), partial response (decrement of PUCAI score${\geq}20$ points), and non-response (decrement of PUCAI score <20 points). Adverse events associated with IFX treatment were also investigated. Results: Eleven pediatric patients with moderate to severe UC had received IFX. The remission rate after IFX treatment was 46% (5/11) and 82% (9/11) at 8 weeks and 54 weeks after IFX treatment, respectively. All patients who were steroid-dependent before treatment with IFX achieved remission at 54 weeks and were able to stop treatment with corticosteroids, while all steroid-refractory patients failed to achieve remission at 54 weeks after treatment with IFX. Conclusion: Response to IFX treatment after 8 weeks may predict a favorable long-term response to IFX treatment in Korean pediatric UC patients.

Effects of the Combination Chemotherapy of Docetaxel and Cisplatin in Non-Small Cell Lung Cancer Patients (비소세포성 폐암환자에서의 Docetaxel과 Cisplatin의 복합요법에 대한 효과)

  • Bang, Eun Sook;Oh, Jung Mi
    • Korean Journal of Clinical Pharmacy
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    • v.12 no.1
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    • pp.1-6
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    • 2002
  • Central Cancer Registry of Korean National Cancer Center in 1999 reported that mortality from lung cancer is higher than mortality from stomach cancer or hepatocellular carcinoma in Korean male. Lung cancer is classified into small cell cancer and non-small cell lung cancer (NSCLC), and NSCLC patients account for $70\%$ of the whole lung cancer patients. The purpose of this study was to evaluate the efficacy and toxicity of docetaxel and cisplatin combination in Korean patients with NSCLC. All patients who had received the combination therapy of docetaxel and cisplatin for histologically confirmed NSCLC in Ajou University Hospital between 2000. $2\~2001$. 4 were retrospectively evaluated for the responses and toxicities of that combination therapy. Nineteen patients were treated with docetaxel 75 $mg/m^2$ on Day 1 and cisplatin 25 $mg/m^2$ on Day 1-3 every 4 weeks. The response for combination regimen was evaluated by CT scans after 2 or 3 cycles of treatments. Seventeen patients were evaluated for the responses and the 19 patients far the toxicities. Among the 19 patients (14 men and 5 women), there were one patient $(5.3\%)$ with stage I disease, 4 patients $(21.1\%)$ with stage III disease, and 14 patients $(73.1\%)$ with stage IV disease. Of the 17 patients who were evaluable for response, complete response (CR) was not observed in any patient while partial response (PR) was observed in 5 patients $(29.4\%)$. The overall response rate (CR+PR) was $29.4\%$. Stable disease (SD) was observed in 11 patients $(64.7\%)$ and progressive disease (PD) in 1 patient $(5.9\%)$. The toxicities were graded by NCI (National Cancer Institute) Common Toxicity Criteria for the evaluable 70 cycles. Grade 3 or 4 neutropenia occurred in 53 cycles $(76\%)$. Four patients were hospitalized due to febrile neutropenia. The combination chemotherapy of docetaxel and cisplatin was effective as NSCLC treatments, however, the regimen must be administered carefully due to its hematological side effects.

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Seismic evaluation and retrofitting of reinforced concrete buildings with base isolation systems

  • Vasiliadis, Lazaros K.
    • Earthquakes and Structures
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    • v.10 no.2
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    • pp.293-311
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    • 2016
  • A parametric study on the nonlinear seismic response of isolated reinforced concrete structural frame is presented. Three prototype frames designed according to the 1954 Hellenic seismic code, with number of floor ranging from 1 to 3 were considered. These low rise frames are representative of many existing reinforced concrete buildings in Greece. The efficacy of the implementation of both lead rubber bearings (LRB) and friction pendulum isolators (FPI) base isolation systems were examined. The selection of the isolation devices was made according to the ratio $T_{is}/T_{fb}$, where Tis is the period of the base isolation system and $T_{bf}$ is the period of the fixed-base building. The main purpose of this comprehensive study is to investigate the effect of the isolation system period on the seismic response of inadequately designed low rise buildings. Thus, the implementation of isolation systems which correspond to the ratio $T_{is}/T_{fb}$ that values from 3 to 5 is studied. Nonlinear time history analyses were performed to investigate the response of the isolated structures using a set of three natural seismic ground motions. The evaluation of each retrofitting case was made in terms of storey drift and storey shear force while in view of serviceability it was made in terms of storey acceleration. Finally, the maximum developed displacements and the residual displacements of the isolation systems are presented.

The role of necroptosis in the treatment of diseases

  • Cho, Young Sik
    • BMB Reports
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    • v.51 no.5
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    • pp.219-224
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    • 2018
  • Necroptosis is an emerging form of programmed cell death occurring via active and well-regulated necrosis, distinct from apoptosis morphologically, and biochemically. Necroptosis is mainly unmasked when apoptosis is compromised in response to tumor necrosis factor alpha. Unlike apoptotic cells, which are cleared by macrophages or neighboring cells, necrotic cells release danger signals, triggering inflammation, and exacerbating tissue damage. Evidence increasingly suggests that programmed necrosis is not only associated with pathophysiology of disease, but also induces innate immune response to viral infection. Therefore, necroptotic cell death plays both physiological and pathological roles. Physiologically, necroptosis induce an innate immune response as well as premature assembly of viral particles in cells infected with virus that abrogates host apoptotic machinery. On the other hand, necroptosis per se is detrimental, causing various diseases such as sepsis, neurodegenerative diseases and ischemic reperfusion injury. This review discusses the signaling pathways leading to necroptosis, associated necroptotic proteins with target-specific inhibitors and diseases involved. Several studies currently focus on protective approaches to inhibiting necroptotic cell death. In cancer biology, however, anticancer drug resistance severely hampers the efficacy of chemotherapy based on apoptosis. Pharmacological switch of cell death finds therapeutic application in drug- resistant cancers. Therefore, the possible clinical role of necroptosis in cancer control will be discussed in brief.

Reversal of Immunogenicity in Pediatric Inflammatory Bowel Disease Patients Receiving Anti-Tumor Necrosis Factor Medications

  • Kang, Elise;Khalili, Ali;Splawski, Judy;Sferra, Thomas J.;Moses, Jonathan
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.21 no.4
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    • pp.329-335
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    • 2018
  • Loss of response to anti-tumor necrosis factor (anti-TNF) agents in the treatment of inflammatory bowel disease (IBD) is a major consideration to maintain sustained response. Reversal of immunogenicity can re-establish response and increase the durability of these agents. Strategies to reverse immunogenicity include dose-intensification and/or the addition of an immunomodulator. However, there is a relative paucity of data on the efficacy of such interventions in pediatric IBD patients. Available reports have not strictly utilized homogenous mobility shift assay, which reports on anti-drug antibodies even in the presence of detectable drug, whereas prior studies have been confounded by the use of drug sensitive assays. We report four pediatric inflammatory bowel disease patients with successful reversal of immunogenicity on an anti-TNF agent using dose intensification and/or addition of an immunomodulator.