• 제목/요약/키워드: AoA

검색결과 481건 처리시간 0.031초

Dietary supplementation with astaxanthin may ameliorate sperm parameters and DNA integrity in streptozotocin-induced diabetic rats

  • Bahmanzadeh, Maryam;Vahidinia, Aliasghar;Mehdinejadiani, Shayesteh;Shokri, Saeed;Alizadeh, Zohreh
    • Clinical and Experimental Reproductive Medicine
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    • 제43권2호
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    • pp.90-96
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    • 2016
  • Objective: Diabetes mellitus (DM) is known to cause many systemic complications as well as male infertility. Astaxanthin (ASTX) is a powerful antioxidant that is involved in a variety of biologically active processes, including those with anti-diabetes effects. The present study investigates the effect of ASTX on the spermatozoa function in streptozotocin (STZ)-induced diabetic rats. Methods: We divided 30 adult rats into three groups (10 rats per group), with a control group that received corn oil mixed with chow. DM was induced by intra-peritoneal injection of STZ. Eight weeks after the STZ injection, half of the diabetic animals were used as diabetic controls, and the rest were treated with ASTX for 56 days. Then the parameters and chromatin integrity of the epididymal sperm were analyzed using chromomycin A3, toluidine blue (TB), and acridine orange (AO) staining. Results: The count, viability, and motility of the epididymal sperm were decreased significantly in the STZ group in comparison with the control group (count and viability, p<0.001; motility, p<0.01). ASTX increased normal morphology and viable spermatozoa compared to the STZ group (morphology, p=0.001; viability, p<0.05). The percentage of abnormal chromatins in TB and AO staining was higher in the STZ group compared to the control group (p<0.001). The mean percentage of TB and AO positive spermatozoa in STZ rats was significantly lower in the STZ+ASTX group (TB, p=0.001; AO, p<0.05). Conclusion: This study observed that in vivo ASTX treatment partially attenuates some detrimental effect of diabetes. Conversely, ASTX improved sperm viability, normal morphology, and DNA integrity.

Ulnar Nerve Injury Caused by the Incomplete Insertion of a Screw Head after Internal Fixation with Dual Locking Plates in AO/OTA Type C2 Distal Humerus Fractures

  • Shin, Jae-Hyuk;Kwon, Whan-Jin;Hyun, Yoon-Suk
    • Clinics in Shoulder and Elbow
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    • 제20권4호
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    • pp.236-239
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    • 2017
  • After dual plating with a locking compression plate for comminuted intraarticular fractures of the distal humerus, the incidence of ulnar nerve injury after surgery has been reported to be up to 38%. This can be reduced by an anterior transposition of the ulnar nerve but some surgeons believe that extensive handling of the nerve with transposition can increase the risk of an ulnar nerve dysfunction. This paper reports ulnar nerve injuries caused by the incomplete insertion of a screw head in dual plating without an anterior ulnar nerve transposition for AO/OTA type C2 distal humerus fractures. When an anatomical locking plate is applied to a distal humeral fracture, locking screws around the ulnar nerve should be inserted fully without protrusion of the screw because an incompletely inserted screw can cause irritation or injury to the ulnar nerve because the screw head in the locking system usually has a slightly sharp edge because screw head has threads. If the change in insertion angle and resulting protruded head of the screw are unavoidable for firm fixation of fracture, the anterior transposition of the ulnar nerve is recommended over a soft tissue shield.

인간공학 기준에 의한 차세대형 주제어실 조명설계 및 조도 휘도 분석- 중국 광동 Ling Ao Phase II NPP MCR 환경디자인을 중심으로- (A Study on Lighting Design and Illumination and Luminance of in Advanced type Control Room by the Standard of Ergonomics - Focused on Ling Ao Phase II NPP MCR Environmental Design in Guangdong, China-)

  • 백승경;이승훈
    • 대한인간공학회지
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    • 제27권2호
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    • pp.73-82
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    • 2008
  • Currently an office in information society is advanced to a digitalized VDT office. The VDT office has a natural luminous system prioritizing visual perception and so importance of lighting design by artificial lighting is emphasized in the VDT office. The purpose of the study is to analyze Illumination and Luminance for lighting design by the standard of ergonomics in the VDT office. The study analyzed Illumination and Luminance in the main control room of an nuclear power plant needing a design of ergonomics ACR(Advanced Control Room) type Ling Ao phase II NPP MCR in Guangdong, China. The study examined the relativity of ACR characteristics to its operator's duties and set up an outline of lighting design, the standard of ergonomics and input data for the analysis. Thus, the study examined appropriateness with the standard of ergonomics setting up the analyzed Illumination and Luminance and drew a conclusion.

Dynamic Economic Dispatch and Control of a Stand-alone Microgrid in DongAo Island

  • Ma, Yiwei;Yang, Ping;Guo, Hongxia;Wang, Yuewu
    • Journal of Electrical Engineering and Technology
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    • 제10권4호
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    • pp.1432-1440
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    • 2015
  • A dynamic economic dispatch and control method is proposed to minimize the overall generating cost for a stand-alone microgrid in DongAo Island, which is integrated with wind turbine generator, solar PV, diesel generator, battery storage, the seawater desalination system and the conventional loads. A new dispatching strategy is presented based on the ranking of component generation costs and two different control modes, in which diesel generator and battery storage alternate to act as the master power source to follow system power fluctuation. The optimal models and GA-based optimization process are given to minimize the overall system generating cost subject to the corresponding constraints and the proposed dispatch strategy. The effectiveness of the proposed method is verified in the stand-alone microgrid in DongAo Island, and the results provide a feasible theoretical and technical basis for optimal energy management and operation control of stand-alone microgrid.

유기색소분자와 고분자전해질 사이의 상호작용 효과에 관한 구조론적 연구 (II). Methylene Blue 및 Acridine Orange의 Chondroitin Sulfate와의 상호작용 (Structural Studies upon the Interactive Effects between Organic Dyestuffs and Polyelectrolytes (Ⅱ). The Interaction of Methylene Blue and Acridine Orange with Chondroitin Sulfate)

  • 박종회;박무순;이홍
    • 대한화학회지
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    • 제31권4호
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    • pp.295-300
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    • 1987
  • 고분자전해질인 Chondroitin sulfate A(CSA) 및 Chondroitin sulfate C(CSC) 존재하에서의 methylene blue(MB) 및 acridine orange(AO)의 metachromasy 현상에 관하여 각각 분광학적 방법으로 연구하였다. P/D값의 변화에 따르는 meta-band의 특성적 변화를 stacking 이론에 의하여 설명하였으며, staking 효과의 정량적 고찰에 의하여 고분자의 반복단위당 결합하는 색소분자의 수를 계산한 결과 MB가 AO보다 강한 stacking 효과를 나타냄이 발견되었다. CAS의 안정한 형태의 골격구조와 dimension을 발견하고 평면 방향색소의 free dimer의 모형을 근거로 CSA의 골격표면에 결합한 색소분자의 stacking모형과 dimension을 제안하였다.

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DMBA로 유발한 Mouse 피부암에 대한 Astaxanthin이 함유된 난황의 항암효과 (Inhibition of DMBA-Induced Mouse Epidermal Carcinogenesis by Astaxanthin-Containing Egg Yolks)

  • 이상호;박철우;이영춘;최의성;김무남;하영래
    • 한국환경성돌연변이발암원학회지
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    • 제18권1호
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    • pp.22-25
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    • 1998
  • Anticarcinogenic activity of astaxanthin-containing egg yolks (designate AEY) was investigated for 7,12-dimethylbenz[a]anthracene (DMBA)-induced two stage mouse epidermal carcinogenesis. Female ICR mouse (6-7 weeks of age) were house in a humidity-and-temperature-controlled facility and subjected to feed and water ad libitum. AEY (10 mg/0.2 ml acetone) was painted on the back of mice 7 days, 3 days and 5 min before DMBA treatment (50 nmole/0.2 ml acetone). One week later after DMBA treatment, 6 ${\mu}g$ tetradecanoyl 12-phorbol 13-O-acetate (TPA) dissolved in 0.2 ml acetone was applied on the mouse twice weekly over a period of 22 weeks. No sample was given to control mice. Control egg yolk (CEY) and astaxanthin-containing oil (designate AO) from Phaffia rhodozyma were used as positive controls. Mouse treated with AEY exhibited 10 tumors per mouse whereas control mouse exhibited 15 tumors per mouse, the fact that 33% reduction of tumor per mouse by AEY treatment. Tumor incidence was also reduced to 15% by AEY treatment when compared to that of control group. Such effects were also seen in CEY and AO treatment groups, but leaser extent. AO gave reduction of food intake and body weights relative to those of AEY and CEY, indicating toxicity of AO. These results suggest that AEY exhibits anticarcinogenic activity for DMBA-induced mouse epidermal carcinogenesis.

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Analysis of Tip/Tilt Compensation of Beam Wandering for Space Laser Communication

  • Seok-Min Song;Hyung-Chul Lim;Mansoo Choi;Yu Yi
    • Journal of Astronomy and Space Sciences
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    • 제40권4호
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    • pp.237-245
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    • 2023
  • Laser communication has been considered as a novel method for earth observation satellites with generation of high data volume. It offers faster data transmission speeds compared to conventional radio frequency (RF) communication due to the short wavelength and narrow beam divergence. However, laser beams are refracted due to atmospheric turbulence between the ground and the satellite. Refracted laser beams, upon reaching the receiver, result in angle-of-arrival (AoA) fluctuation, inducing image dancing and wavefront distortion. These phenomena hinder signal acquisition and lead to signal loss in the course of laser communication. So, precise alignment between the transmitter and receiver is essential to guarantee effective and reliable laser communication, which is achieved by pointing, acquisition, and tracking (PAT) system. In this study, we simulate the effectiveness of tip/tilt compensation for more efficient laser communication in the satellite-ground downlink. By compensating for low-order terms using tip/tilt mirror, we verify the alleviation of AoA fluctuations under both weak and strong atmospheric turbulence conditions. And the performance of tip/tilt correction is analyzed in terms of the AoA fluctuation and collected power on the detector.

Robust feedback-linearization control for axial power distribution in pressurized water reactors during load-following operation

  • Zaidabadi nejad, M.;Ansarifar, G.R.
    • Nuclear Engineering and Technology
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    • 제50권1호
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    • pp.97-106
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    • 2018
  • Improved load-following capability is one of the most important technical tasks of a pressurized water reactor. Controlling the nuclear reactor core during load-following operation leads to some difficulties. These difficulties mainly arise from nuclear reactor core limitations in local power peaking: the core is subjected to sharp and large variation of local power density during transients. Axial offset (AO) is the parameter usually used to represent the core power peaking. One of the important local power peaking components in nuclear reactors is axial power peaking, which continuously changes. The main challenge of nuclear reactor control during load-following operation is to maintain the AO within acceptable limits, at a certain reference target value. This article proposes a new robust approach to AO control of pressurized water reactors during load-following operation. This method uses robust feedback-linearization control based on the multipoint kinetics reactor model (neutronic and thermal-hydraulic). In this model, the reactor core is divided into four nodes along the reactor axis. Simulation results show that this method improves the reactor load-following capability in the presence of parameter uncertainty and disturbances and can use optimum control rod groups to maneuver with variable overlapping.

Hypocholesterolemic Effect of Amaranth Squalene (Amaranth esculantus) in Rats Fed a High Cholesterol Diet

  • Kim, Hye-Kyung;Chang, Young-Jeong;Heo, Ho-Jin;Cho, Hong-Yon;Hong, Bum-Shik ;Shin, Dong-Hoon
    • Preventive Nutrition and Food Science
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    • 제8권1호
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    • pp.13-18
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    • 2003
  • In experiment 1, rats (n=6) fed diet containing 10 g/kg cholesterol for 4 wk (control) with either no amaranth (control), amaranth grain (300 g/kg, AG) or amaranth oil (90 g/kg, AO). Both the AG and AO groups had lower concentration of serum and hepatic cholesterol and triglyceride than the controls (p < 0.05). Fecal excretions of cholesterol and bile acid in AO group increased about 4 fold and 2 fold, respectively, while AG affected only bile acid excretion (p < 0.05). In experiment 2, rats (n=6) were fed the cholesterol diet for 4 wk and injected intraperitoneally with saline (control) or amaranth squalene (AS) for 7d. The hypolipidemic effect of AS was evident in both serum and liver. Fecal excretions of cholesterol and bile acid were greater (p < 0.05) in AS than control. HMG-CoA (3-hydroxy-3-methylglutaryl coenzyme A) reductase activity was reduced in AS group (11.6%, p=0.13). This study suggests that the cholesterol-lowering effect of AS is mediated by greater fecal elimination of steroids through interference with cholesterol absorption.

고받음각에서 조종성능 및 안정성 증강을 위한 제어법칙에 관한 연구 (A Study on Control Law Augmentation in order to Improve Aircraft Controllability and Stability in High Angle of Attack)

  • 김종섭;황병문;이동규
    • 한국항공우주학회지
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    • 제33권10호
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    • pp.60-67
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    • 2005
  • 현대의 고성능 전투기는 한계받음각 내에서 적절한 조종성(Controllability) 및 안정성(Stability)을 확보하고 있어야 한다. 고받음각에서 항공기가 이탈에 진입할 수 있는 한계값은 항공기 형상설계에 직결되는 문제이다. 하지만 현대의 고성능 전투기는 전기식 비행제어계통(Digital Fly-By-Wire Flight Control System)을 사용하여 고받음각 제어법칙을 설계함으로써 한계값 내에서 항공기의 안정성을 보장하고 있다. 현재, T-50 세로축 고받음각 제어법칙에는 (+)한계받음각 이상으로의 비행을 제한하는 받음각 제한기(Angle of Attack Limiter)가 설계되어 있다. 그러나 (-)한계받음각 이상으로 비행을 제한하는 받음각 제한기는 설계되어 있지 않아, 조종사의 과도한 (-)세로축 기동에 대해 항공기가 이탈에 진입할 수 있다. 그리고 T-50 비행시험에서 PA에서 과도한 (+)세로축 기동 시, 받음각(Angle of Attack)이 현재 설계되어 있는 한계받음각을 초과하는 문제점이 발생하였다. 본 논문에서는 고받음각 제어법칙을 일부 수정하여 한계받음각 내에서 항공기의 세로축 조종성능을 향상시키고, 항공기 안정성을 확보할 수 있는 제어법칙에 관한 연구를 수행하였다.