• Title/Summary/Keyword: Magnetic fluid

검색결과 781건 처리시간 0.024초

Performance Analysis of Water-Water Heat Pump System of 100 kW Scale for Cooling Agricultural Facilities

  • Kang, Youn Ku;Ryou, Young Sun;Jang, Jae Kyung;Kim, Young Hwa;Kim, Jong Goo;Kang, Geum Chun
    • Journal of Biosystems Engineering
    • /
    • 제39권1호
    • /
    • pp.34-38
    • /
    • 2014
  • Purpose: In this study, the performance of cooling system with the water-water heat pump system of 100kW scale made for cooling agricultural facilities, especially for horticultural facilities, was analyzed. It was intended to suggest performance criteria and performance improvement for the effective cooling system. Methods: The measuring instruments consisted of two flow meters, a power meter and thermocouples. An ultrasonic and a magnetic flow meter measured the flow rate of the water, which was equivalent to heat transfer fluid. The power meter measured electric power in kW consumed by the heat pump system. T-type thermocouples measured the temperature of each part of the heat pump system. All of measuring instruments were connected to the recorder to store all the data. Results: When the water temperature supplied into the evaporator of the heat pump system was over $20^{\circ}C$, the cooling Coefficient Of Performance(COP) of the system was higher than 3.0. As the water temperature supplied into the evaporator, gradually, lowered, the cooling COP, also, decreased, linearly. Especially, when the water temperature supplied into the evaporator was lower than $15^{\circ}C$, the cooling COP was lower below 2.5. Conclusions: In order to maintain the cooling COP higher than 3.0, we suggest that the water temperature supplied into evaporator from the thermal storage tank should be maintained above $20^{\circ}C$. Also, stratification in the thermal storage tank should be formed well and the circulating pumps and the pipe lines should be arranged in order for the relative low-temperature water to be stored in the lower part of the thermal storage tank.

중추신경 장애를 가진 시추 종의 개에서 지속적인 가속성 심실고유 율동 (Persistent Accelerated Idioventricular Rhythm in a Shih Tzu with Central Neuropathy)

  • 한숙희;현창백
    • 한국임상수의학회지
    • /
    • 제27권4호
    • /
    • pp.440-444
    • /
    • 2010
  • 5.2 kg의 7살령 중성화 된 수컷 시추가 심각한 신경증상(paddling, 무의식, 실명, 발작)으로 내원하였다. 내원 당시 ECG 상에 심실 유래의 심박동 약 140회의 가속성 심실 고유박동(AVIR)이 지속적으로 나타났다. 이 환축은 자기공명영상법(MRI)과 뇌척수액검사(CSF)를 통해 파종성 육아종성 뇌수막염(GME)로 잠정 진단 내려졌다. 신경증상은 스테로이드제와 항경련제, 이뇨제, 항생제, 20% 만니톨 정맥 주사 등으로 호전 되었으며 부정맥은(AIVR) mexiletin으로 통제되었다. 신경학적인 문제에 대한 응급 처치 후 증상의 호전에도 불구하고 항부정맥제 처치 없이는 심장의 리듬이 불안정 했기 때문에 항부정맥 처치는 신경증상이 완전히 소실 될 때까지 유지되었다.

원인불명의 수막뇌염을 보인 개에서 Cytosine Arabinoside와 Prednisolone으로 치료한 2례 (Combined Cytosine Arabinoside and Prednisolone Therapy for Meningoencephalitis of Unknown Etiology in 2 Dogs)

  • 김태호;서경원;이영흔;황철용;이영원;윤화영
    • 한국임상수의학회지
    • /
    • 제27권4호
    • /
    • pp.462-467
    • /
    • 2010
  • A Maltese (5-years old, castrated male) and a Yorkshire Terrier (8-years old, intact female) were referred to Seoul National University Hospital for Animals with ataxia, circling, depression and anorexia. It was suspected to meningoencephalitis of unknown etiology (MUE) based on neurological signs, magnetic resonance imaging findings, cerebrospinal fluid analysis and canine distemper virus antigen test. Immunosuppressive dose of corticosteroid was initially chosen to treat in two dogs. However, the clinical signs were relapsed and side effects had arisen including polyuria, polydipsia, calcinosis cutis, liver enzyme elevation, weight gain and abdominal distension. Combination therapy of cytosine arabinoside (CA) and prednisolone (PDS) was tried. With this combination, the clinical signs were resolved and the side effects were alleviated. The dose of PDS was tapered to 0.5 mg/kg q48h in one case and the PDS was discontinued in the other case. These cases suggested that combined CA and PDS therapy may be significantly useful for the treatment of MUE uncontrolled by PDS alone.

Efficacy of arthrocentesis and lavage for treatment of post-traumatic arthritis in temporomandibular joints

  • Park, Joo-Young;Lee, Jong-Ho
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • 제46권3호
    • /
    • pp.174-182
    • /
    • 2020
  • Objectives: Joint injuries frequently lead to progressive joint degeneration that causes articular disc derangement, joint inflammation, and osteoarthritis. Such arthropathies that arise after trauma are defined as post-traumatic arthritis (PTA). Although PTA is well recognized in knee and elbow joints, PTA in the temporomandibular joint (TMJ) has not been clearly defined. Interestingly, patients experiencing head and neck trauma without direct jaw fracture have displayed TMJ disease symptoms; however, definitive diagnosis and treatment options are not available. This study will analyze clinical aspects of PTA in TMJ and their treatment outcomes after joint arthrocentesis and lavage. Materials and Methods: Twenty patients with history of trauma to the head and neck especially without jaw fracture were retrospectively studied. Those patients developed TMJ disease symptoms and were diagnosed by computed tomography or magnetic resonance imaging. To decrease TMJ discomfort, arthrocentesis and lavage with or without conservative therapy were applied, and efficacy was evaluated by amount of mouth opening and pain scale. Statistical differences between pre- and post-treatment values were evaluated by Wilcoxon signed-rank test. Results: Patient age varied widely between 20 and 80 years, and causes of trauma were diverse. Duration of disease onset was measured as 508 post-trauma days, and 85% of the patients sought clinic visit within 2 years after trauma. In addition, 85% of the patients showed TMJ disc derangement without reduction, and osteoarthritis was accompanied at the traumatized side or at both sides in 40% of the patients. After arthrocentesis or lavage, maximal mouth opening was significantly increased (28-44 mm on average, P<0.001) and pain scale was dramatically decreased (7.8-3.5 of 10, P<0.001); however, concomitant conservative therapy showed no difference in treatment outcome. Conclusion: The results of this study clarify the disease identity of PTA in TMJ and suggest early diagnosis and treatment options to manage PTA in TMJ.

Characterization of Itraconazole Semisolid Dosage Forms Prepared by Hot Melt Technique

  • Shim, Sang-Young;Ji, Chang-Won;Sah, Hong-Kee;Park, Eun-Seok;Lee, Beom-Jin
    • Archives of Pharmacal Research
    • /
    • 제29권11호
    • /
    • pp.1055-1060
    • /
    • 2006
  • The objective of this study was to formulate itraconazole semisolid dosage forms and characterize their physicochemical properties. Itraconazole and excipients such as polysorbate 80, fatty acids, fatty alcohols, oils and organic acids were melted at $160^{\circ}C$. The fused solution was then cooled immediately at $-10^{\circ}C$ to make wax-like semisolid preparations. Their physicochemical attributes were first characterized using differential scanning calorimetry, Fourier transform infrared spectroscopy and nuclear magnetic resonance spectrometry. The solubility of itraconazole in semisolid preparations and their dispersability in the simulated gastric fluid were also determined. Our semisolid preparations did not show any distinct endothermic peak of a crystalline form of itraconazole around $160-163^{\circ}C$. This suggested that it was changed into amorphous one, when it was formulated into semisolid preparations. In addition, the distinctive functional peaks and chemical shifts of itraconazole were well retained after processing into semisolid preparations. It could be inferred from the data that itraconazole was stable during incorporation into semisolid preparations by the hot melt technique. In particular, itraconazole semisolid preparations composed of polysorbate 80, fatty acids and organic acids showed good solubility and dissolution when dispersed in an aqueous medium. It was anticipated that the semisolid dosage forms would be industrially applicable to improving the bioavailability of poorly water-soluble drugs.

Non-infected and Infected Bronchogenic Cyst: The Correlation of Image Findings with Cyst Content

  • Jeon, Hong Gil;Park, Ju Hwan;Park, Hye Min;Kwon, Woon Jung;Cha, Hee Jeong;Lee, Young Jik;Park, Chang Ryul;Jegal, Yangjin;Ahn, Jong-Joon;Ra, Seung Won
    • Tuberculosis and Respiratory Diseases
    • /
    • 제76권2호
    • /
    • pp.88-92
    • /
    • 2014
  • We hereby report a case on bronchogenic cyst which is initially non-infected, then becomes infected after bronchoscopic ultrasound (US)-guided transesophageal fine-needle aspiration (FNA). The non-infected bronchogenic cyst appears to be filled with relatively echogenic materials on US, and the aspirate is a whitish jelly-like fluid. Upon contrast-enhanced MRI of the infected bronchogenic cyst, a T1-weighted image shows low signal intensity and a T2-weighted image shows high signal intensity, with no enhancements of the cyst contents, but enhancements of the thickened cystic wall. The patient then undergo video-assisted thoracic surgery 14 days after the FNA. The cystic mass is known to be completely removed, and the aspirate is yellowish and purulent. To understand the image findings that pertain to the gross appearance of the cyst contents will help to diagnose bronchogenic cysts in the future.

Regional Grey and White Matter Changes in the Brain Reward System Among Patients with Alcohol Dependency

  • Park, Mi-Sook;Seok, Ji-Woo;Kim, Eun-Ye;Noh, Ji-Hye;Sohn, Jin-Hun
    • 감성과학
    • /
    • 제20권4호
    • /
    • pp.113-126
    • /
    • 2017
  • The purpose of the study was to find grey matter (GM) and white matter (WM) volume reduction in the brain reward system among patients with alcohol dependency. This study investigated regional GM and WM in chronic alcoholic patients, focusing primarily on the reward system, including principal components of the mesocorticolimbic reward circuit as well as cortical areas with modulating and oversight functions. Sixteen abstinent long-term chronic alcoholic men and demographically matched 16 healthy control men participated in the study. Morphometric analysis was performed on magnetic resonance brain scans using voxel-based morphometry (VBM)-diffeomorphic Anatomical Registration through Exponentiated Liealgebra (DARTEL). We derived GM and WM volumes from total brain and cortical and subcortical reward-related structures. Morphometric analyses that revealed the total volume of GM and WM was reduced and cerebrospinal fluid (CSF) was increased in the alcohol group compared to control group. The pronounced volume reduction in the reward system was observed in the GM and WM of the nucleus accumbens (NAc), GM of the amygdala, GM and WM of the hippocampus, WM of the thalamus, GM and WM of the insula, GM of the dorsolateral prefrontal cortex (DLPFC), GM of the orbitofrontal cortex (OFC), GM of the cingulate cortex (CC), GM and WM of the parahippocampal gyrus in the alcohol group. We identified volume reductions in WM as well as GM of reward system in the patients with alcohol dependency. These structural deficits in the reward system elucidate underlying impairment in the emotional and cognitive processing in alcoholism.

Psychotic Symptoms of Hashimoto's Encephalopathy: A Diagnostic Challenge

  • Savarimuthu, Monisha K;Tsheringla, Sherab;Mammen, Priya
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
    • /
    • 제30권1호
    • /
    • pp.42-44
    • /
    • 2019
  • Hashimoto's encephalopathy (HE) is a rare and underdiagnosed neuropsychiatric illness. We present the case of a 17-year-old girl who was admitted to a tertiary-care psychiatric center with acute onset psychosis and fever. Her psychotic symptoms were characterized by persecutory and referential delusions, as well as tactile and visual hallucinations. Her acute behavioral disturbance warranted admission and treatment in a psychiatric setting (risperidone tablets, 3 mg/day). She had experienced an episode of fever with a unilateral visual acuity defect approximately 3 years before admission, which was resolved with treatment. Focused clinical examination revealed an enlarged thyroid, and baseline blood investigations, including thyroid function test results were normal. Abnormal laboratory investigations revealed elevated anti-thyroid peroxidase (anti-TPO) and anti-thyroglobulin (anti-TG) levels (anti-TPO of 480 IU/mL; anti-TG of 287 IU/mL). Results of other investigations for infection, including cerebrospinal fluid examination, electroencephalography, and brain magnetic resonance imaging were normal. She was diagnosed with HE and was treated with intravenous corticosteroids (methylprednisolone up to 1 g/day; tapered and discontinued after a month). The patient achieved complete remission of psychotic symptoms and normalization of the anti-thyroid antibody titers. Currently, at the seventh month of follow-up, the patient is doing well. This case highlights the fact that in the absence of well-defined clinical diagnostic criteria, a high index of suspicion is required for early diagnosis of HE. Psychiatrists need to explore for organic etiologies when dealing with acute psychiatric symptoms in a younger age group.

2단 감압 수소레귤레이터의 연성해석 및 도금특성에 관한 연구 (A Study of Fluid Structure Interaction Analysis and Coating Characteristics of a Two-stage Pressure Reduction Hydrogen Regulator)

  • 송재욱;김승모
    • 한국산학기술학회논문지
    • /
    • 제22권1호
    • /
    • pp.37-44
    • /
    • 2021
  • 수소연료전지차(FCEV)는 전기를 자체 생산하는 연료전지를 동력원으로 하고 있으며 기존 기계식 레귤레이터의 출구압은 시스템 사양에 의해 제작 시점에서 고정되며 순간적인 수소 공급량에 의한 출구압 강하가 발생하는 경우 수소의 공급유량이 부정확해지는 문제가 있다. 본 연구에서는 기존에 존재하는 1단 기계식 감압 레귤레이터를 보완하기 위한 2단 감압 레귤레이터의 형상 설계 및 재질 선정을 수행하였다. 2단계 감압을 통한 맥동과 느린 응답을 보상하고 고압 편차 문제를 해결하기 위해 감압 유닛의 접촉면 형상을 가공성을 고려하여 설계하였다. 기밀성 측면에서 TPU의 변형량은 최대 15.82% 작은 변위량을 보였으며, 재질 선정에서는 2단 감압에 보편성을 확보하고 다양한 수소 연료 공급시스템에 적용 가능한 전자식 솔레노이드를 고려하여 자성체를 선정하고 적절한 도금 종류를 검증하기 위한 수소 취성 및 내식성 평가를 실시하였다. 시편의 표면 부식은 Cr 도금의 경우에서만 발생되지 않았으며, 인장 시험을 통해 부식과정간 연신율을 비교하였을 때, 2% 이내의 차이를 확인하였다.

Long-Term Management of a Refractory Corticosteroid Responsive Tremor Syndrome

  • Kim, Soomin;Kim, Yoonji;Kim, Ji-Hee;Kim, Hyeon-Jin;Lee, Ji-Hye;Geum, Migyeong;Kim, Ha-Jung
    • 한국임상수의학회지
    • /
    • 제38권3호
    • /
    • pp.143-146
    • /
    • 2021
  • A 2-year-old intact female Maltese dog was presented with generalized involuntary tremors and nystagmus without regular direction. The dog was conscious the whole time while it was trembling. Its involuntary tremors were alleviated at rest or during sleep. Magnetic resonance imaging (MRI) revealed asymmetric hydrocephalus and caudal occipital malformation. In cerebrospinal fluid (CSF) analysis, a trace of protein was found and total nucleated cell count (TNCC) was slightly increased. However, infectious pathogens were not found. In complete blood count, there was a mild leukocytosis. After the patient received anticonvulsants (midazolam, phenobarbital, KBr), diuretics (furosemide) with an anti-inflammatory drug (prednisolone, 0.5 mg/kg PO bid), and a proton-pump inhibitor (omeprazole), it showed no improvement. The patient was tentatively diagnosed with corticosteroid responsive tremor syndrome. So the anticonvulsants and diuretics were discontinued and the dose of prednisolone was increased to an immunosuppressive dose (1 mg/kg PO bid). After administering the immunosuppressive dose of prednisolone, the patient did not show nystagmus. Its tremors were much alleviated. However, they did not disappear. Five weeks later, the patient showed gradual improvement but still was trembling when moving around. Nine weeks later, its tremors were similar to before. So diazepam (0.3 mg/kg PO sid) was added to the treatment. After that, its tremors were alleviated more. Prednisolone and diazepam were maintained for about five months, with tapering of the dose of prednisolone (until 0.5 mg/kg PO sid). About 7 months later after the treatment was started, the dog was trembling rarely except when it was excited. Therefore, diazepam was discontinued. This case describes a refractory white dog shaker syndrome successfully managed with long-term administration of a steroid and diazepam.