• Title/Summary/Keyword: Artificial heart

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Ubiquitous healthcare model based on context recognition (상황인식에 기반한 유비쿼터스 헬스케어 모델)

  • Kim, Jeong-Won
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.9
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    • pp.129-136
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    • 2010
  • With mobile computing, wireless sensor network and sensor technologies, ubiquitous computing services are being realized and could satisfy the feasibility of ubiquitous healthcare to everyone. This u-Healthcare service can improve life quality of human since medical service can be provided to anyone, anytime, and anywhere. To confirm the vision of u-Healthcare service, we've implemented a healthcare system for heart disease patient which is composed of two components. Front-end collects various signals such as temperature, blood pressure, SpO2, and electrocardiogram, etc. As a backend, medical information server accumulates sensing data and performs back-end processing. To simply transfer these sensing values to a medical team may be too trivial. So, we've designed a model based on context awareness for more improved medical service which is based on artificial neural network. Through rigid experiments, we could confirm that the proposed system can provide improved medical service.

The 21-century Techo-Scientific Predicaments and Its Call for Post-anthropocentric Worldviews: Luth Ozeki's A Tale for The Time Being (21세기 기술과학적 곤경과 탈인간중심주의적 세계관의 요청: 루스 오제키의 『시간존재를 위한 이야기』)

  • Lee, Kyung-Ran
    • English & American cultural studies
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    • v.17 no.1
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    • pp.129-162
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    • 2017
  • Ruth Ozeki(Japanese-American female novelist)?s recent novel, A Tale for the Time Being (2013) draws our attention because the fiction shows very interesting fictional experiments, especially in terms of post-humanism. Indeed, the novel is not a science fiction at all which has been, and still is, the typical fictional field employed in the discussion for the transhumanism and posthumanism. It also does not include any cybogs, robots, or aliens which provoke the posthumanism-related issues like mind/body, human/nonhuman, nature/culture relations. Indeed, it seems "merely" represent realistic day-to-day lives of ordinary people living in contemporary Japan and Canada, and in very minute and particular details at that. Indeed, the central action of the main characters of the novel seems very traditional, that is on the one hand writing a diary by a teenage girl who is counting the days and weeks before her suicide and on the other hand reading it by a female novelist who happens to find her diary several years later. Nevertheless, I would like to suggest that underneath this traditional narrative surface are simmering post-humanist and post-anthropocentric worldviews beyond liberal Humanism which takes human beings to be exceptional against human or non-human others. Not only in narrative contents and characterizations but also through narrative structure and strategies, the novel enacts post-humanist and post-anthropocentric worldviews which are interestingly drawn from both age-old Buddhist ideas and modern eco-philosophy and quantum physics. I would like to stress that what triggers the author's fictional experiments helping our rethinking and redefining "what human beings are" and "what the relation between humans and nonhumans" is not merely intellectual interests but her keen and passionate response to the heart-breaking pains and sufferings of human and nonhuman beings caused by the contemporary natural-artificial catastrophes and techno-scientific predicaments.

Can Artificial Intelligence Boost Developing Electrocatalysts for Efficient Water Splitting to Produce Green Hydrogen?

  • Jaehyun Kim;Ho Won Jang
    • Korean Journal of Materials Research
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    • v.33 no.5
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    • pp.175-188
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    • 2023
  • Water electrolysis holds great potential as a method for producing renewable hydrogen fuel at large-scale, and to replace the fossil fuels responsible for greenhouse gases emissions and global climate change. To reduce the cost of hydrogen and make it competitive against fossil fuels, the efficiency of green hydrogen production should be maximized. This requires superior electrocatalysts to reduce the reaction energy barriers. The development of catalytic materials has mostly relied on empirical, trial-and-error methods because of the complicated, multidimensional, and dynamic nature of catalysis, requiring significant time and effort to find optimized multicomponent catalysts under a variety of reaction conditions. The ultimate goal for all researchers in the materials science and engineering field is the rational and efficient design of materials with desired performance. Discovering and understanding new catalysts with desired properties is at the heart of materials science research. This process can benefit from machine learning (ML), given the complex nature of catalytic reactions and vast range of candidate materials. This review summarizes recent achievements in catalysts discovery for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The basic concepts of ML algorithms and practical guides for materials scientists are also demonstrated. The challenges and strategies of applying ML are discussed, which should be collaboratively addressed by materials scientists and ML communities. The ultimate integration of ML in catalyst development is expected to accelerate the design, discovery, optimization, and interpretation of superior electrocatalysts, to realize a carbon-free ecosystem based on green hydrogen.

Computerized Multiple 15-hue tests for Quantifying Color Vision Acuity (색각 능력의 정량적 평가를 위한 전산화된 다중 15-색상 배열 검사법)

  • Ko S.T.;Hong S.C.;Choi M.J.
    • Journal of Biomedical Engineering Research
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    • v.21 no.3 s.61
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    • pp.321-331
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    • 2000
  • Multiple 15-hue tests were designed and implemented on a PC in the study so as to quickly and quantitatively evaluate color vision acuity. Difficulty of the test was control)ed by the value of CDBACC (color difference between adjacent color chips) calculated using a CIELAB formula. The multiple 15-hue tests consist of eight of the hue tests (test 3-10) and three of the basic color (red, green, blue) tests (test 11-13). The 15 colors used for the hue tests were specified by the 15 color coordinates that were located at a constant distance (d = 2. 3. 5. 7, 10, 20, 30. 40) from white reference in the CIE chromaticity coordinate system and were separated by a constant color difference (CDBACC = 0.75, 1.1, 1.8. 2.5. 3.5. 7.5. 11, 14) from the adjacent chips. The color coordinates for the 15 chips for the basic color tests were the same as those of the 15 points spaced equally by a constant color difference (6.87 for the green color test. 7.27 for the red color test, 7.86 for the blue color test) from the white reference along the axis of red, green and blue. Thirty normal subjects who were not color blind were taken to undergo the multiple 15-hue tests. It was observed that most of the subjects correctly arranged color chips for the tests with CDBACC greater than 5, whereas no one correctly answered for those with CDBACC less than 2. Rapid changes in the number of the subjects correctly arranged took place when CDBACC of the tests was between 2 and 4.5. In the basic color tests, unlike the hue tests having similar values of CDBACC, it was seen that the subjects arranged color chips even less correctly. It was found that JNCD (just noticeable color difference) - a measure of color vision acuity was about 3 in average for the subjects. The JNCD was chosen as the value of the CDBACC of the test for which about $50\%$ of the subjects failed to successfully arrange color chips. ERCCA (error rate of color chips arrangement) for the test with CDBACC the same as the JNCD was shown to be about $20\%$. It is expected that the multi 15-hue tests implemented on a PC in the study will be an economical tool to quickly and quantitatively evaluate color vision acuity and, accordingly, the tests can be used for early diagnosis to massive potential patients suffering from diseases (ex. diabetes, glaucoma) which may induce changes in color vision acuity.

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A Study on an Effective Decellularization Technique for a Xenograft Cardiac Valve: the Effect of Osmotic Treatment with Hypotonic Solution (이종 심장 판막 이식편에서 효과적인 탈세포화 방법에 관한 연구; 저장성 용액(hypotonic solution)의 삼투압 처치법 효과)

  • Sung, Si-Chan;Kim, Yong-Jin;Choi, Sun-Young;Park, Ji-Eun;Kim, Kyung-Hwan;Kim, Woong-Han
    • Journal of Chest Surgery
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    • v.41 no.6
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    • pp.679-686
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    • 2008
  • Background: Cellular remnants in the bioprosthetic heart valve are known to be related to a host's immunologic response and they can form the nidus for calcification. The extracellular matrix of the decellularized valve tissue can also be used as a biological scaffold for cell attachment, endothelialization and tissue reconstitution. Thus, decellularization is the most important part in making a bioprosthetic valve and biological caffold. Many protocols and agents have been suggested for decellularization, yet there ave been few reports about the effect of a treatment with hypotonic solution prior to chemical or enzymatic treatment. This study investigated the effect of a treatment with hypotonic solution and the appropriate environments such as temperature, the treatment duration and the concentration of sodium dodecylsulfate (SDS) for achieving proper decellularization. Material and Method: Porcine aortic valves were decellularized with odium dodecylsulfate at various concentrations (0.25%, 0.5%), time durations (6, 12, 24 hours) and temperatures ($4^{\circ}C$, $20^{\circ}C$)(Group B). Same the number of porcine aortic valves (group A) was treated with hypotonic solution prior to SDS treatment at the same conditions. The duration of exposure to the hypotonic solution was 4, 7 and 14 hours and he temperature was $4^{\circ}C$ and $20^{\circ}C$, respectively. The degree of decellularization was analyzed by performing hematoxylin and eosin staining. Result: There were no differences in the degree of decellularization between the two concentrations (0.25% 0.5%) of SDS. Twenty four hours treatment with SDS revealed the best decellularization effect for both roups A and B at the temperature of $4^{\circ}C$, but there was no differences between the roups at $20^{\circ}C$. Treatment with hypotonic solution (group A) showed a better ecellularization effect at all the matched conditions. Fourteen hours treatment at $4^{\circ}C$ ith ypotonic solution prior to 80S treatment revealed the best decellularization effect. The treatment with hypotonic solution at $20^{\circ}C$ revealed a good decellularization effect, but his showed significant extracellular matrix destruction. Conclusion: The exposure of porcine heart valves to hypotonic solution prior to SDS treatment is highly effective for achieving decellularization. Osmotic treatment with hypotonic solution should be considered or achieving decellularization of porcine aortic valves. Further study should be carried out to see whether the treatment with hypotonic solution could reduce the exposure duration and concentration of chemical detergents, and also to evaluate how the structure of the extracellular matrix of the porcine valve is affected by the exposure to hypotonic solution.

Results of Surgical Management in Patients with Cardiac and Arterial Manifestations of Behcet's Syndrome (심장 및 동맥계를 침범한 베체트씨 증후군 환자의 수술 후 결과)

  • 원종윤;장병철;이도연;박상준
    • Journal of Chest Surgery
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    • v.35 no.1
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    • pp.36-42
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    • 2002
  • Background: To evaluate the efficiency of surgical treatment in patients with cardiac valvular and arterial involvement of Behcet's syndrome. Material and Method: 12 patients underwent surgical treatment due to the valvular heart diseases and the various arterial diseases associated with Behest's syndrome over 7 years; 6 with valvular heart disease, 1 with annuloaortic ectasia, 1 with ascending aortic aneurysm, 4 with pseudoaneurysms in abdominal aorta(n=2), carotid artery(n=1), and popliteal artery(n=1). All 12 patients had received valvular replacement(n=6) and the artificial(n=5) or autologous(n=1) graft interposition. We followed the results of these surgical treatments. Result: Operations were technically successful in all 12 patients and peri-operative complication was not demonstrated. However, 10 patients had recurrences; 6 with valvular dehiscence, 3 with pseudoaneurysm at anastostomosis site, and 1 with aorto-duodenal fistula. The duration of recurrence was 1 to 55 months(mean: 15.7$\pm$ 16.2 months). 7 patients underwent the second operation and among them, 4 patients showed repeated recurrences. Overall, 5 patients died 2 to 25 months after the operation(mean: 13.6 months), because of the bleeding at the anastomosis site Five patients did not present recurrence after the first(n=2) or the second operation(n=3) and their follow up duration was 5 to 60 months(mean: 45.8$\pm$41.7 months). Five patients received immune-suppressive therapy after the first(n=2) and second operation(n=3). Three did not shown recurrence for the 13, 29 and 33 months. Conclusion: Post-operative prognosis of arterial manifestation of Behcet's syndrome was not encouraging and if possible, other treatment strategy should be considered.

Outcome of pregnant mothers with systemic lupus erythematosus (focusing on congenital heart block) (전신성 홍반성 루푸스 산모의 출산아의 임상적 고찰 (완전 방실 블록을 중심으로))

  • Baek, Hey Sung;Choi, Jae Hyung;Kim, Nam Su;Kim, Chang Ryul;Moon, Su Ji
    • Clinical and Experimental Pediatrics
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    • v.49 no.4
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    • pp.381-387
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    • 2006
  • Purpose : Neonatal lupus is characterized by congenital complete heart block(CCHB), cutaneous rash, and laboratory abnormalities in infants born to mothers with systemic lupus erythematosus(SLE). This study aims to examine the incidence of CCHB and clinical outcome in neonates born to mothers with SLE. Methods : The study group consisted of 49 neonates, born from 57 pregnancies of 55 women with SLE, diagnosed at Hanyang University Hospital for the period between January 1997 and January 2005. Clinical and laboratory data were retrospectively identified from medical record. Results : There were 5(8.8 percent) spontaneous abortions and one(1.8 percent) still births among 57 pregnancies of 55 mothers. Of 49 live births, 15(26.3 percent) were premature and eight(12.3 percent) were small for their gestational age. There was one(1.8 percent) CCHB suspected during pregnancy on fetal echocardiograpy in a fetus of mother with systemic lupus erythematosus and the fetus was not born by artificial abortion because of mother. There was no CCHB among EKG findings of 49 newborns. Laboratory testing showed hematologic abnormalities among 25.6 percent(10/39) of the babies. 5.1 percent(2/39) and 7.7 percent(3/39) of them were diagnosed as neutropenia, and thrombocytopenia was seen respectively. Anti-SSA(Ro) and antiphospholipid antibodies were predictive factors for prematurity(P=0.003, P=0.049). Anticardiolipin antibodies were predictive factors for ventilatory care(P=0.018). Conclusion : The incidence of CCHB among neonates born to mothers with SLE, which was measured in this study, was lower than that in earlier studies. A high incidence of hematologic abnormalities was found in our study. It is suggested that careful examination should be made of skin for the diagnosis of neonatal lupus.

Effects of Gamichangbaek-san(Jiaweichangbai-san) on Anti-inflammatory, Analgesic, Anti-febrile Activities and Immune Responses in Carrageenan-induced Arthritic Animals (가미창백산(加味蒼栢散)이 Carrageenan유발 동물모델 관절염의 소염, 진통, 해열 및 면역에 미치는 영향)

  • Han, Young-Gyu;Park, Young-Hoi;Keum, Dong-Ho;Lee, Myeong-jong
    • Journal of Korean Medicine Rehabilitation
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    • v.15 no.1
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    • pp.127-141
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    • 2005
  • Objectives : This study was performed to investigate the effects of Gamichangbaek-san(Jiaweichangbai-san) on anti-inflammatory, analgesic, anti-febrile and immune response on the arthritis of carrageenan-induced animals. Methods and Materials : Rats were classified into control and sample groups which are 7 individuals each for the experiments about anti-inflammatory and anti-febrile. Each of the 7 mice were classified into normal, control, sample groups for the analgesic experiments. Gamichangbai-san(Jiaweichangbai-san) was administered to sample group and normal saline was administered to normal and control groups. Arthritis was induced by injection of 1% carrageenan $0.1m{\ell}$ and Gamichangbaek-san(Jiaweichangbai-san) was administered after 30 minutes. The change of edema in Carrageenan-induced Arthritic Rats' Paws was measured after 1 hour and 5 hours from the injection of carraqeenan with Plethysmometer(7150, UGO BASILE, ltaly) by Winter' method. WBC, Lymphocyte and ESR were measured by heart puncture and CD4+ T cell, CD8+ T cell and CD4+/CD8+ T cell ratio were measured from the spleen tissue. Writhing syndrom was measured with Tail flick unit(UGO BASILE, Italy) in the experiments conducted to check the analgesic activity. The temperature of the paws of carrageenan-induced arthritic rats was measured by Laser thermometer. Rectal temperature was measured by Yeast's method in anti-febrile experiments. Immune response was measured by CD4+, CD8+ T cell ratio and CD4+/CD8+ T cell ratio. Results : 1. It was recognized that Gamichangbaek-san(Jiaweichangbai-san) decreased the increase rate of Paw Edema effectively with statistical significance. 2. It was recognized that Gamichangbaek-san(Jiaweichangbai-san) decreased WBC, Lymphocyte and ESR with statistically high significance. 3. It was recognized that Gamichangbaek-san(Jiaweichangbai-san) did not show significant analgesic effect, but the Pressure pain threshold of the paws was increased with statistical significance. 4. It was recognized that Gamichangbaek-san(Jiaweichangbai-san) decreased rectal temperature effectively and had an anti-febrile effect about the febrile of a joint with statistical significance. 5. It was recognized that Gamichangbaek-san(Jiaweichangbai-san) increased CD4+ T cell ratio with statistically high significance and increased CD+8 T cell ratio with statistical non significance but increased CD4+/CD8+ T cell ratio effectively with statistical significance, too. Conclusions : According to the above results, it can be concluded Gamichangbaek-san(Jiaweichangbai-san) showed the treatment effects on the artificial arthritis resulted from carageenan in rats and it is suggested that more interest and study in the security for the clinical use were needed.

Effects of Diuretics on Warfarin Responses in Patients with Atrial Fibrillation (심방세동 환자에서 Warfarin 반응성에 이뇨제가 미치는 영향)

  • Park, Hee Joo;La, Hyen-Oh;Gwak, Hye Sun
    • Korean Journal of Clinical Pharmacy
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    • v.23 no.2
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    • pp.151-157
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    • 2013
  • Purpose: Warfarin is the most widely used anticoagulant drug for preventing cardiovascular diseases after ischemic stroke and thromboembolism related to atrial fibrillation, artificial heart valves, deep vein thrombosis, and pulmonary embolism. Warfarin is commonly used in combination with other drugs such as diuretics in order to treat the comorbidity. Although several warfarin-diuretics interactions have been reported, the results are conflicting. Therefore, the initial aim of this study was to identify the effects of diuretics on the warfarin response in patients with atrial fibrillation. Methods: One hundred forty six patients with atrial fibrillation who were on anticoagulation therapy with warfarin and maintained INR levels of 2-3 for three consecutive times were followed up, retrospectively. Stable warfarin doses and INR per stable warfarin dose were compared according to age, gender, comorbidity, and concurrent medication. The stable warfarin dose was defined as the maintenance dose of warfarin of the measured patient whose INR was within the target INR range more than 3 times consecutively. Results: The differences of stable warfarin doses in patients with ($3.22{\pm}1.21$ mg/day) and without ($3.58{\pm}1.14$ mg/day) diuretics were marginally significant (P=0.069). On the other hand, stable warfarin doses were $2.97{\pm}1.10$ mg/day in patients with thiazide (n=36) and $3.58{\pm}1.14$ mg/day in patients without diuretics (n=82), which was statistically significant (p=0.009). INR values per stable warfarin dose in patients with diuretics and thiazide were $0.84{\pm}0.31$ and $0.90{\pm}0.34$, respectively, which were statistically different from those without diuretics ($0.72{\pm}0.21$, P=0.010 and P=0.006, respectively). Age, gender, and concurrent use of thiazide diuretics were found to have significant influence on the warfarin response from multivariate analysis. Conclusion: Our study showed that the concurrent use of thiazide diuretics could increase the response of warfarin in patient with atrial fibrillation. Therefore, clinicians should be aware that warfarin dose needs to be adjusted when it is used with thiazide diuretics concomitantly.

Spectral Properties of the Sound From the Mechanical Valve Employed in an Implantable Biventricular Assist Device (이식형 양심실 보조 장치에 사용된 기계식 판막의 음향 스펙트럼 특성)

  • 최민주;이서우;이혁수;민병구
    • Journal of Biomedical Engineering Research
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    • v.22 no.5
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    • pp.439-448
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    • 2001
  • This paper considers the acoustical characteristics of the closing click sounds of the mechanical valves employed in an implantable biventricular assist device (BYAD) and their re1evance to the Physical states of the valved. Bj rk Shiley Convexo Concave tilting disk valve was chosen for the study and acoustic measurement was made for the BYAD operated in a mock circulatory system as well as implanted in an animal (sheep). In the BYAD operated in the mock circulatory system. three different states of the valve were examined, ie. normal. mechanically damaged. pseudo-thrombus attached. Microphone measurement for the BVAD implanted in the animal was carried out for five days at a regular time interval from one day after implantation. Characteristic spectrum of the sound from the valve was estimated using Multiple Signal Classification (MUSIC) in which the optimal order was determined according to Bayesian Information Criterion (BIC) . It was observed that the mechanical damage of the valve resulted in changes of the structure of the acoustic spectrum. In contrast. the thrombus formed on the valve did not change much the basic structure of the spectrum but brought about altering the spectral Peak frequencies and energies. Maximum spectral Peak (MSP) with the greatest energy was seen at 2 kHz for the normal valve and it was shifted to 3 kHz for the calve attaching the Pseudo-thrombus. Unlike the normal valve, strong spectral Peak appeared around 7 kHz in the sound from the valve mechanically damaged. In the case of the BYAD implanted in the animal. as the thrombus grew, acoustic energy was reduced relatively more in the low frequency components (〈 2 kHz) and the frequencies of the 1st, 2nd and 3rd MSP were increased little. The thrombus formation would result in reduction in both the variability of the 1st, 2nd and 3rd MSP and the value of the BIC optimal order.

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