• 제목/요약/키워드: Combination mechanism

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가변길이 엔드팁을 갖는 원추형 스프링을 이용한 도약로봇의 이동성 향상 (Mobility Improvement of a Jumping Robot using Conical Spring with Variable Length Endtip)

  • 김기석;김병상;송재복;임충혁
    • 제어로봇시스템학회논문지
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    • 제15권11호
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    • pp.1108-1114
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    • 2009
  • Mobility is one of the most important features for a guard robot since it should be operated in rough places. A wheel-based mobile robot capable of jumping is an appropriate structure for a guard robot because it can easily satisfy the requirements for small guard robots. The jumping robot can reach a higher place more rapidly than other locomotion methods. This research proposes a small robot equipped with the jumping mechanism based on the conical spring with the variable length endtip. The variable length endtip enables the independent control of the jump force and jump angle which are related to the jump height and jump distance, respectively. Various experiments demonstrated that the proposed jumping mechanism can provide the independent control of jump force and jump angle, and improve the mobility of a small robot to overcome an obstacle. Furthermore, a combination of the jumping mechanism and the PSD sensor to measure the distance to the step enable the jumping robot to autonomously climb stairs.

Metformin에 추가로 병용되는 SGLT2 inhibitors의 효능과 안전성에 관한 고찰 (A Review on Efficacy and Safety of SGLT2 Inhibitors as Add-on Therapy with Metformin)

  • 정경혜
    • 한국임상약학회지
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    • 제28권3호
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    • pp.243-249
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    • 2018
  • Background: The new type of diabetes treatment, SGLT2 inhibitors, has been approved for monotherapy and combination therapy, but medical insurance is only allowed in combination therapy with metformin, which is the first choice for type 2 diabetes treatment. Methods: The SGLT2 inhibitors prescribed in Korea are dapagliflozin, empagliflozin and ipragliflozin. A review was conducted using Pubmed to evaluate efficacy and safety for these medications with metformin combination therapy. 10 studies were selected by searching for keywords and related references and were reviewed in full. The mechanism of action, pharmacokinetics, and the economics of treatment with SGLT2 inhibitors were examined. Results: SGLT2 inhibitors had moderate glycemic control when added to the treatment of patients with type 2 diabetes who were not being regulated by metformin monotherapy. They also showed positive effects such as weight loss, as well as the lowering of blood pressure. Hypotension and serious side effects were relatively low. However, the risk of genital infection was increased. Conclusion: The SGLT2 inhibitors are a new class of drugs that promote glucose excretion in the urine. They are a good choice for combination therapy with metformin for the treatment of type 2 diabetes, with weight loss and very low risk of serious side effects.

Enhancing Anti-Cancer Therapy with Selective Autophagy Inhibitors by Targeting Protective Autophagy

  • Jae-Sung Park;Min Ju Lee;Seong Bin Jo;Young Ae Joe
    • Biomolecules & Therapeutics
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    • 제31권1호
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    • pp.1-15
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    • 2023
  • Autophagy is a process of eliminating damaged or unnecessary proteins and organelles, thereby maintaining intracellular homeostasis. Deregulation of autophagy is associated with several diseases including cancer. Contradictory dual roles of autophagy have been well established in cancer. Cytoprotective mechanism of autophagy has been extensively investigated for overcoming resistance to cancer therapies including radiotherapy, targeted therapy, immunotherapy, and chemotherapy. Selective autophagy inhibitors that directly target autophagic process have been developed for cancer treatment. Efficacies of autophagy inhibitors have been tested in various pre-clinical cancer animal models. Combination therapies of autophagy inhibitors with chemotherapeutics are being evaluated in clinal trials. In this review, we will focus on genetical and pharmacological perturbations of autophagy-related proteins in different steps of autophagic process and their therapeutic benefits. We will also summarize combination therapies of autophagy inhibitors with chemotherapies and their outcomes in pre-clinical and clinical studies. Understanding of current knowledge of development, progress, and application of cytoprotective autophagy inhibitors in combination therapies will open new possibilities for overcoming drug resistance and improving clinical outcomes.

Combination of oxaliplatin and β-carotene suppresses colorectal cancer by regulating cell cycle, apoptosis, and cancer stemness in vitro

  • Junghyeun Lee;Seung Chul Heo;Yuri Kim
    • Nutrition Research and Practice
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    • 제18권1호
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    • pp.62-77
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    • 2024
  • BACKGROUND/OBJECTIVES: Colorectal cancer (CRC) is the third most common cancer worldwide with a high recurrence rate. Oxaliplatin (OXA) resistance is one of the major reasons hindering CRC therapy. β-Carotene (BC) is a provitamin A and is known to have antioxidant and anticancer effects. However, the combined effect of OXA and BC has not been investigated. Therefore, this study investigated the anticancer effects and mechanism of the combination of OXA and BC on CRC. MATERIALS/METHODS: In the present study, the effects of the combination of OXA and BC on cell viability, cell cycle arrest, and cancer stemness were investigated using HCT116, HT29, OXA-resistant cells, and human CRC organoids. RESULTS: The combination of OXA and BC enhanced apoptosis, G2/M phase cell cycle arrest, and inhibited cancer cell survival in human CRC resistant cells and CRC organoids without toxicity in normal organoids. Cancer stem cell marker expression and self-replicating capacity were suppressed by combined treatment with OXA and BC. Moreover, this combined treatment upregulated apoptosis and the stem cell-related JAK/STAT signaling pathway. CONCLUSIONS: Our results suggest a novel potential role of BC in reducing resistance to OXA, thereby enhances the anticancer effects of OXA. This enhancement is achieved through the regulation of cell cycle, apoptosis, and stemness in CRC.

Bearing capacity of micropiled-raft system

  • Hwang, Tae-Hyun;Kim, Kang-Hyun;Shin, Jong-Ho
    • Structural Engineering and Mechanics
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    • 제63권3호
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    • pp.417-428
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    • 2017
  • The micropile has been mainly used under the concept of supplementing structural support or reinforcing soft ground. For the micropiled-raft system which uses a micropile and a raft in combination in particular, it is generally considered as ground reinforcement rather than foundation components considering the bearing capacity of the micropile in many cases. In this study, the bearing capacity mechanism of the micropiled-raft system is investigated through a physical model test and numerical method. The numerical results have shown that not only the slender-pile-effect of the micropile, but also the ground reinforcement effect, increase the bearing capacity considerably. The bearing capacity formula of the micropiled-raft system is derived based on the failure mechanism obtained through model tests. The formula is verified and proposed as a design chart.

얀센 메커니즘을 이용한 자동주행 보행 로봇의 최적 설계 (Optimal design of an automatic walking robot based on Jansen's Mechanism)

  • 김동찬;김무환;이민수;박제열;조성욱
    • EDISON SW 활용 경진대회 논문집
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    • 제6회(2017년)
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    • pp.540-546
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    • 2017
  • Bipedal robots tend to have greater mobility than conventional treaded or wheeled robots yet they are commonly complicated by instabilities in balance. This paper presents a bipedal robot based upon Jansen's locomotive mechanism which addresses these challenges in stability and efficiency. In order to achieve a functioning robot, we considered a multitude of variables in its motion including, the Ground Score, Drag Score, step size, foot lift, stride, and instantaneous speed of the Jansen mechanism. Matlab and Jansen Opt solver were used to optimize the legs of the robot. A trial and error experimental method was used to determine the best combination of link lengths, and m.Sketch was used to model our results. Finally, we drew the entirety of the robot's figure by using the Edison design.

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얀센 메커니즘을 적용한 보행 로봇 다리의 운동학 해석 (Kinematic Analysis of A Walking Robot Leg Based on Jansen Mechanism)

  • 김영두;방정현
    • EDISON SW 활용 경진대회 논문집
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    • 제5회(2016년)
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    • pp.424-428
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    • 2016
  • This paper presents the kinematics of a walking robot leg based on Jansen mechanism. By using simple mathematics, all trajectories of walking robot leg links can be calculated. A foot point trajectory is used to evaluate the performance of a walking robot leg. Trial and Error method is used to find a best combination of link lengths under certain restrictions. All simulations are performed by Matlab. Ground score, drag score, step size, foot lift, instant speed, and average speed of foot point trajectories are used for selecting the best one.

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Rotational behavior of exposed column bases with different base plate thickness

  • Cui, Yao;Wang, Fengzhi;Li, Hao;Yamada, Satoshi
    • Steel and Composite Structures
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    • 제32권4호
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    • pp.497-507
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    • 2019
  • Exposed column base connections are used in low- to mid-rise steel moment resisting frames. This paper is to investigate the effect of the base plate thickness on the exposed column base connection strength, stiffness, and energy dissipation. Five specimens with different base plate thickness were numerically modelled using ABAQUS software. The numerical model is able to reproduce the key characteristics of the experimental response. Based on the numerical analysis, the critical base plate thickness to identify the base plate and anchor rod yield mechanism is proposed. For the connection with base plate yield mechanism, the resisting moment is carried by the flexural bending of the base plate. Yield lines in the base plate on the tension side and compression side are illustrated, respectively. This type of connection exhibits a relatively large energy dissipation. For the connection with anchor rod yield mechanism, the moment is resisted through a combination of bearing stresses of concrete foundation on the compression side and tensile forces in the anchor rods on the tension side. This type of connection exhibits self-centering behavior and shows higher initial stiffness and bending strength. In addition, the methods to predict the moment resistance of the connection with different yield mechanisms are presented. And the evaluated moment resistances agree well with the values obtained from the FEM model.

Diagnostic Significance of Combined Detection of Epstein-Barr Virus Antibodies, VCA/IgA, EA/IgA, Rta/IgG and EBNA1/IgA for Nasopharyngeal Carcinoma

  • Cai, Yong-Lin;Li, Jun;Lu, Ai-Ying;Zheng, Yu-Ming;Zhong, Wei-Ming;Wang, Wei;Gao, Jian-Quan;Zeng, Hong;Cheng, Ji-Ru;Tang, Min-Zhong
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권5호
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    • pp.2001-2006
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    • 2014
  • The objective of this study was to investigate the diagnostic significance of EBV antibody combined detection for nasopharyngeal carcinoma (NPC) in a high incidence region of southern China. Two hundred and eleven untreated NPC patients, 203 non-NPC ENT patients, and 210 healthy controls were recruited for the study. The titers of VCA/IgA and EA/IgA were assessed by immunoenzyme assay, and the levels of Rta/IgG and EBNA1/IgA were determined by enzyme-linked immunosorbent assay. The levels of VCA/IgA, EA/IgA, Rta/IgG and EBNA1/IgA demonstrated no association with gender or age (p>0.05). The receiver operating characteristic curve and the area under the curve were used to evaluate the diagnostic value. The sensitivity of VCA/IgA (98.1%) and the specificity of EA/IgA (98.5%) were the highest. When a logistic regression model was used to combine the results from multiple antibodies to increase the accuracy, the combination of VCA/IgA+Rta/IgG, whose area under the curve was 0.99, had the highest diagnostic efficiency, and its sensitivity, specificity and Youden index were 94.8%, 98.0% and 0.93 respectively. The data suggest that the combination of VCA/IgA+Rta/IgG may be most suitable for NPC serodiagnosis.