• Title/Summary/Keyword: ejection

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Effect of Host Egg Color Dimorphism on Interactions Between the Vinous-throated Parrotbill (Paradoxornis webbianus) and Common Cuckoo (Cuculus canorus)

  • Yoo, Jeong-Chil;Lee, Jin-Won
    • Animal cells and systems
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    • v.8 no.2
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    • pp.77-80
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    • 2004
  • To investigate the effect of host egg color dimorphism on the vinous-throated parrotbill (Paradoxornis webbianus) - common cuckoo (Cuculus canorus) interactions, we monitored breeding nests of vinous-throated parrotbills, and conducted model egg experiments, using two colors: white and blue. Of the 190 nests examined in this study, cuckoo parasitism occurred at 10 nests (8 blue and 2 white egg clutches, respectively), and only blue cuckoo eggs were found. This frequency was similar to the egg-color ratio of all host nests found (151 blue and 39 white egg clutches). Vinous-throated parrotbills showed high rejection rate towards both cuckoo eggs and model ones. There was a significant difference in rejection rates towards mimetic (blue) and non-mimetic (white) eggs in blue egg clutches. Mimetic eggs put in nests took significantly longer to be rejected than non-mimetic ones. The most common rejection method used by the hosts was egg ejection (puncture-ejection). The costs of ejecting non-mimetic eggs tended to be lower than those of ejecting mimetic eggs. These results indicate that egg-color dimorphism in this species favors the individuals having white egg clutches in terms of higher rejection rate and lower ejection costs of the parasitic eggs. This study also suggests that egg-color dimorphism of the vinous-throated parrotbill decreases the effect of cuckoo parasitism on host populations.

Clinical Study of Ventricular Function Following Open Heart Surgery by Radionuclide Angiocardiogram - left ventricular ejection fraction by ECG gated blood pool scan - (방사성 동위원소를 이용한 개심술 전후의 심실기능 변화에 관한 연구: ECG gated blood pool scan을 이용한 ejection fraction 검사)

  • Lee, Jeong-Cheol;Kim, Gyu-Tae
    • Journal of Chest Surgery
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    • v.19 no.1
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    • pp.25-34
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    • 1986
  • Recently, radionuclide angiocardiogram is one of the most common procedure for assessment of ventricular performance due to its distinctive advantages such as safety, accuracy, and ease of repeated studies. Also, measurement and comparison between pre and postoperative left ventricular ejection fraction [LVEF] are meaningful for assessing the severity of myocardial damage which occurred during open heart surgery and the status of myocardial recovery. We obtained pre and post operative LVEF using radionuclide angiocardiogram on 30 patients composed of atrial septal defect, ventricular septal defect, cyanotic congenital heart disease, and valvular heart disease who undergone the open heart surgery from March to august 1984. The study revealed that ventricular septal defect and mitral valvular heart disease showed 8.1% and 6.2% decreases of postoperative LVEF, respectively. But, there are little increases of postoperative LVEF in the atrial septal defect and cyanotic congenital heart disease. In ventricular septal defect, each group of Qp/Qs over 2.0 and systolic pulmonary artery pressure over 50mmHg showed significant 17% and 14.7% decreases of postoperative LVEF, respectively. Considering the duration of the aortic cross clamping times and closing methods of VSD, each group of duration over 30 min. and of patch closure showed 13.9% and 14.2% decreases of LVEF between pre and postoperative status respectively which was significant finding statistically.

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A Systems Engineering Approach to Multi-Physics Analysis of CEA Ejection Accident

  • Sebastian Grzegorz Dzien;Aya Diab
    • Journal of the Korean Society of Systems Engineering
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    • v.19 no.2
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    • pp.46-58
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    • 2023
  • Deterministic safety analysis is a crucial part of safety assessment, particularly when it comes to demonstrating the safety of nuclear power plant designs. The traditional approach to deterministic safety analysis models is to model the nuclear core using point kinetics. However, this simplified approach does not fully reflect the real core behavior with proper moderator and fuel reactivity feedbacks during the transient. The use of Multi-Physics approach allows more precise simulation reflecting the inherent three-dimensionality (3D) of the problem by representing the detailed 3D core, with instantaneous updates of feedback mechanisms due to changes of important reactivity parameters like fuel temperature coefficient (FTC) and moderator temperature coefficient (MTC). This paper addresses a CEA ejection accident at hot full power (HFP), in which the underlying strong and un-symmetric feedback between thermal-hydraulics and reactor kinetics exist. For this purpose, a multi-physics analysis tool has been selected with the nodal kinetics code, 3DKIN, implicitly coupled to the thermal-hydraulic code, RELAP5, for real-time communication and data exchange. This coupled approach enables high fidelity three-dimensional simulation and is therefore especially relevant to reactivity initiated accident (RIA) scenarios and power distribution anomalies with strong feedback mechanisms and/or un-symmetrical characteristics as in the CEA ejection accident. The Systems Engineering approach is employed to provide guidance in developing the work in a systematic and efficient fashion.

Sudden Death and Ventricular Arrhythmias in Heart Failure With Preserved Ejection Fraction

  • Jae Hyung Cho
    • Korean Circulation Journal
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    • v.52 no.4
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    • pp.251-264
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    • 2022
  • Heart failure with preserved ejection fraction (HFpEF) accounts for approximately half of all heart failure (HF) cases. The prevalence of HFpEF is increasing due to an aging population with hypertension, diabetes mellitus, and obesity. HFpEF remains a challenging clinical entity due to a lack of effective treatment options. Traditional HF medications have not been shown to reduce mortality of patients with HFpEF, and an implantable cardioverter-defibrillator is not indicated due to normal ejection fraction. Sudden death is the most common mode of death in patients with HFpEF; however, the underlying mechanisms of sudden death are not fully elucidated. Although ventricular arrhythmias are responsible for the majority of sudden deaths in general, their contribution to sudden deaths in HFpEF patients is likely less significant. The mechanisms of ventricular arrhythmias in HFpEF are 1) reduced conduction velocity due to ventricular hypertrophy, 2) delayed repolarization due to potassium current down-regulation, 3) calcium leakage due to altered excitation-contraction coupling, and 4) increased ventricular fibrosis caused by systemic inflammation. Hypertension and subsequent ventricular hypertrophy reduce the conduction velocity in HFpEF hearts via heterogeneous distribution of connexin 43. Delayed repolarization caused by potassium current down-regulation in HFpEF hearts provides a window for early afterdepolarization to trigger ventricular arrhythmias. Altered excitation-contraction coupling in HFpEF can cause calcium to leak and trigger delayed afterdepolarization. Increased systemic inflammation and subsequent ventricular fibrosis provide substrates for re-entry. Further research is warranted to investigate the detailed mechanisms of ventricular arrhythmias in HFpEF.

Medical Management of Patients With Heart Failure and Reduced Ejection Fraction

  • Barry Greenberg
    • Korean Circulation Journal
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    • v.52 no.3
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    • pp.173-197
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    • 2022
  • Treatment options for patients with heart failure (HF) with reduced ejection fraction (HFrEF) have expanded considerably over the past few decades. Whereas neurohormonal modulation remains central to the management of patients with HFrEF, other pathways have been targeted with drugs that have novel mechanisms of action. The angiotensin receptor-neprilysin inhibitors (ARNIs) which enhance levels of compensatory molecules such as the natriuretic peptides while simultaneously providing angiotensin receptor blockade have emerged as the preferred strategy for inhibiting the renin angiotensin system. Sodium glucose cotransporter 2 (SGLT2) inhibitors which were developed as hypoglycemic agents have been shown to improve outcomes in patients with HF regardless of their diabetic status. These agents along with beta blockers and mineralocorticoid receptor antagonists are the core medical therapies for patients with HFrEF. Additional approaches using ivabradine to slow heart rate in patients with sinus rhythm, the hydralazine/isosorbide dinitrate combination to unload the heart, digoxin to provide inotropic support and vericiguat to augment cyclic guanosine monophosphate production have been shown in well-designed trials to have beneficial effects in the HFrEF population and are used as adjuncts to the core therapies in selected patients. This review provides an overview of the medical management of patients with HFrEF with focus on the major developments that have taken place in the field. It offers prospective of how these drugs should be employed in clinical practice and also a glimpse into some strategies that may prove to be useful in the future.

A Study for the Gallbladder Stone on the Dietary Factors (식이요인에 따른 담석형성에 관한 연구)

  • Sim, Hyun-Sun;Jung, Hong-Ryang
    • Journal of radiological science and technology
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    • v.30 no.4
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    • pp.391-397
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    • 2007
  • Background/Aims : Gallbladder(GB) stone is the most common disease in the biliary system, and the incidence is gradually increasing in Korea. This change may include rapidly proceeding urbanization and changing food factor. We performed this study to investigate related GB stones and contraction of GB as dietary factors. Methods : We investigated 129 subjects(mean age : 47 years). GB stone group is 9 subjects(M: 2, F: 7) in Namyangju-si. Control group without GB stone is 18 subjects(M: 6, F: 12) in Wi-do island. For subjects without GB stone, diabetes mellitus decide 4(M: 2, F: 2) and then each after eat flesh and meat of estimated by experimental group ejection fraction rate(%). Results : Ejection fraction rate of GB were different between meat and fishes intake. When ate the meat in experiment for hypothetical verification, when become ejection fraction rate of meal GB 210 minutes, was the highest and when ate fish, the ejection fraction rate of GB was the highest in meal 120 minutes. Conclusions : After meats intaking the bile inside the GB is stagnant long and the GB stone is formed. We studied the results GB motility may important play a role on GB stone formation.

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Effects of anesthesia on echocardiograms in myocardial infarcted dogs (심근경색 유발견에서 마취가 심초음파에 미치는 영향)

  • Yoon, Jung-hee;Sung, Jai-ki
    • Korean Journal of Veterinary Research
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    • v.37 no.3
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    • pp.669-685
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    • 1997
  • The present study was performed to evaluate the effects of xylazine and tiletamine + zolazepam on echocardiograms before and after experimental myocardial infarctions in clinically normal dogs taken preliminary examinations related to cardiac function. The results are as follows. With xylazine administration, left ventricle end-diastolic dimension, left ventricle end-systolic dimension, left atrium/aorta, ejection time and velocity of circumferential fiber shortening increased and mitral valve CD slope, % delta D decreased(p<0.01). In tiletamine+zolazepam administered group, interventricular septum amplitude(p<0.01), mitral valve DE slope(p<0.05) and ejection time(p<0.01) decreased and left atrium/aorta, ejection time also decreased compared with xylazine group(p<0.01). In 48 hours after experimental myocardial infarction group, anterior aortic wall amplitude decreased compared with control, xylazine, tiletamine + zolazepam group, respectively(p<0.01). Posterior aortic wall amplitude decreased compared with control(p<0.01). Left ventricle end systolic dimension increased compared with control and tiletamine + zolazepam group, respectively(p<0.01). Left ventricular posterior wall end systolic dimension decreased compared with control(p<0.01). Left ventricular posterior wall amplitude decreased compared with control and tiletamine+zolazepam group(p<0.01). Left atrium/aorta decreased compared with xylazine group(p<0.01). % thickening left ventricular posterior wall decreased compared with control(p<0.05). % delta D decreased compared with control and tiletamine+zolazepam group(p<0.01). Ejection time decreased compared with xylazine(p<0.01). Velocity of circumferential fiber shortening increased compared with control and tiletamine + zolazepam group(p<0.01). With xylazine administration 48 hours after experimental myocardial infarction, anterior aortic wall amplitude, posterior aortic wall amplitude decreased compared with control(p<0.01). Left ventricle end-diastolic dimension increased compared with control(p<0.01). Left ventricle end-systolic dimension increased compared with control and tiletamine + zolazepam group, respectively(p<0.01). Left ventricular posterior wall end-systolic dimension and left ventricular posterior wall end-diastolic dimension decreased compared with control(p<0.01). Left atrium/aorta decreased compared with xylazine group(p<0.01). % thickening left ventricular posterior. wall(p<0.05) and % delta D(p<0.01) decreased compared with control. Velocity of circumferential fiber shortening increased compared with tiletamine + zolazepam group(p<0.01). With tiletamine + zolazepam administration 48 hours after experimental myocardial infarction, anterior aortic wall amplitude decreased compared with control, xylazine and tiletamine+zolazepam group, respectively(p<0.01). Posterior aortic wall amplitude decreased compared with control(p<0.01). Left ventricle end-systolic dimension increased compared with control and tiletamine+zolazepam group(p<0.01). Left ventricular posterior wall end-systolic dimension, left ventricular posterior wall end-diastolic dimension and interventricular septum amplitude decreased compared with control(p<0.01). Left atrium/aorta decreased compared with xylazine group(p<0.01). % delta D decreased compared with control and tiletamine + zolazepam group(p<0.01). Ejection time decreased compared with xylazine group and velocity of circumferential fiber shortening increased compared withtiletamine+zolazepam group(p<0.01). Conclusively, echocardiography was proved to be a useful, diagnostic, non-invasive and simple method for establishing the diagnosis of myocardial infarction and evaluating the effects of drug on cardiac function before and after myocardial infarction.

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A Case of Pleural Effusion in a Patient with Heart Failure with Preserved Ejection Fraction Improved by A Combined Korean-Western Medicine Approach (좌심실 수축 기능 보전 심부전증으로 인한 흉수에 대한 한양방 복합치료 치험 1례)

  • Ha, Won Jung;Seo, Yuna;Lee, Young seon;Cho, Ki-Ho;Mun, Sang-Kwan;Jung, Woo-Sang;Kwon, Seungwon
    • The Journal of the Society of Stroke on Korean Medicine
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    • v.22 no.1
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    • pp.45-56
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    • 2021
  • ■ Background Heart Failure with Preserved Ejection Fraction(HFpEF) is a heart failure that appears to have normal contraction function. In the case of HFpEF, no pharmacological therapy has been found to improve clinical prognosis, so it should be approached as an symptomatic treatment, therefore alternatives are needed due to concerns over adverse effects such as electrolyte imbalance caused by medication. ■ Case report A 81 year old female patient with Heart Failure with Preserved Ejection Fraction(HFpEF) patient complained dyspnea. Herbal prescription Mokbanggi-tang and Oryeongsan was administered on 6th day and 8th day respectively since the symptoms started. The NYHA Classification and Chest X-ray had been evaluated during the treatment period. Until the 7th day, the patient was classified as Class II, and when discharged from the hospital on the 28th day, it gradually improved and was classified as Class II. Chest X-Ray took on 2nd day showed pleural effusion and it was aggravated until 13th day. Follow up Chest X-Ray showed improving state of pleural effusion from 20th day and gradually got better. Mokbanggi-tang treatment continued for 52 days and stopped on 58th day. After Mokbanggi-tang treatment ended, only Oryeongsan treatment was maintained. ■ Conclusion The present case report suggests that Korean-Western medicine approach with Mokbangki-tang and Oryeongsan might be effective to pleural effusion and heart failure symptoms such as poor physical activity shown in a NYHA Classification. This shows that Mokbanggi-tang and Oryeongsan can be a therapeutic option as a treatment for patient with Heart Failure with Preserved Ejection Fraction(HFpEF).