127 research outputs found
Enhanced magnetic and thermoelectric properties in epitaxial polycrystalline SrRuO3 thin film
Transition metal oxide thin films show versatile electrical, magnetic, and
thermal properties which can be tailored by deliberately introducing
macroscopic grain boundaries via polycrystalline solids. In this study, we
focus on the modification of the magnetic and thermal transport properties by
fabricating single- and polycrystalline epitaxial SrRuO3 thin films using
pulsed laser epitaxy. Using epitaxial stabilization technique with atomically
flat polycrystalline SrTiO3 substrate, epitaxial polycrystalline SrRuO3 thin
film with crystalline quality of each grain comparable to that of
single-crystalline counterpart is realized. In particular, alleviated
compressive strain near the grain boundaries due to coalescence is evidenced
structurally, which induced enhancement of ferromagnetic ordering of the
polycrystalline epitaxial thin film. The structural variations associated with
the grain boundaries further reduce the thermal conductivity without
deteriorating the electronic transport, and lead to enhanced thermoelectric
efficiency in the epitaxial polycrystalline thin films, compared with their
single-crystalline counterpart.Comment: 24 pages, 5 figure
A Grid Web Portal for Aerospace
A wind tunnel simulation requires high-performance computing power like
supercomputers and deep knowledge of this subject. Those requirements make win tunnel
simulation difficult. Grid technology will make these difficulties simpler by providing easy to use
grid web portal. By using grid web portal, scientist can execute simulation and access to highperformance
computing power without any serious difficulties. In this paper will present a grid
web portal for a wind tunnel simulation that is used in Aerospace area.OAIID:oai:osos.snu.ac.kr:snu2006-01/104/0000004648/27SEQ:27PERF_CD:SNU2006-01EVAL_ITEM_CD:104USER_ID:0000004648ADJUST_YN:NEMP_ID:A001138DEPT_CD:446CITE_RATE:0FILENAME:A Grid Web Portal for Aerospace.pdfDEPT_NM:기계항공공학부EMAIL:[email protected]:
Thyroid Transcription Factor-1 Facilitates Cerebrospinal Fluid Formation by Regulating Aquaporin-1 Synthesis in the Brain
In the brain, aquaporin-1 (AQP-1), a water channel for high osmotic water permeability, is mainly expressed in the apical membrane of the ventricular choroid plexus and regulates formation of cerebrospinal fluid (CSF). Although the physiology of AQP-1 has been the subject of several publications, much less is known about the trans-acting factors involved in the control of AQP-1 gene expression. Here we report that TTF-1, a homeodomain-containing transcriptional regulator, is coexpressed with AQP-1 in the rat brain choroid plexus and enhances AQP-1 gene transcription by binding to conserved core TTF-1-binding motifs in the 5'-flanking region of the AQP-1 gene. Intracerebroventricular administration of an antisense TTF-1 oligodeoxynucleotide significantly decreased AQP-1 synthesis and reduced CSF formation. In addition, blockade of TTF-1 synthesis increased survival of the animals following acute water intoxication-induced brain edema. These results suggest that TTF-1 is physiologically involved in the transcriptional control of AQP-1, which is required for CSF formation
Enhanced magnetic and thermoelectric properties in epitaxial polycrystalline SrRuO3 thin film
Transition metal oxide thin films show versatile electrical, magnetic, and
thermal properties which can be tailored by deliberately introducing
macroscopic grain boundaries via polycrystalline solids. In this study, we
focus on the modification of the magnetic and thermal transport properties by
fabricating single- and polycrystalline epitaxial SrRuO3 thin films using
pulsed laser epitaxy. Using epitaxial stabilization technique with atomically
flat polycrystalline SrTiO3 substrate, epitaxial polycrystalline SrRuO3 thin
film with crystalline quality of each grain comparable to that of
single-crystalline counterpart is realized. In particular, alleviated
compressive strain near the grain boundaries due to coalescence is evidenced
structurally, which induced enhancement of ferromagnetic ordering of the
polycrystalline epitaxial thin film. The structural variations associated with
the grain boundaries further reduce the thermal conductivity without
deteriorating the electronic transport, and lead to enhanced thermoelectric
efficiency in the epitaxial polycrystalline thin films, compared with their
single-crystalline counterpart.Comment: 24 pages, 5 figure
Clinical Review of Endogenous Endophthalmitis in Korea: A 14-Year Review of Culture Positive Cases of Two Large Hospitals
PURPOSE: To identify the clinical features and outcomes of endogenous endophthalmitis in Korea.
MATERIALS AND METHODS: We reviewed 18 patients with endogenous endophthalmitis at 2 Korean hospitals, treated over a 14 year period between January 1993 and December 2006.
RESULTS: The comorbidities observed in these cases were diabetes mellitus and liver cirrhosis. The most common pathogens, which were found in 7 patients each (38.9%), were Klebsiella pneumonia and Pseudomonas aeruginosa. All patients were treated with systemic antibiotics and fortified topical antibiotics. A surgical approach including vitrectomy was performed in 9 cases (50.0%). The prognosis was generally poor, and visual acuity improved slightly in 6 patients (33.3%).
CONCLUSION: In this study, diabetes mellitus and Klebsiella pneumonia showed a close relationship with endogenous endophthalmitis, respectively. Endogenous endophthalmitis is a serious risk to sight and careful attention to establishing the diagnosis and management may decrease the ocular morbidity.ope
Identification of MYC as an antinecroptotic protein that stifles RIPK1-RIPK3 complex formation
The underlying mechanism of necroptosis in relation to cancer is still unclear. Here, MYC, a potent oncogene, is an antinecroptotic factor that directly suppresses the formation of the RIPK1-RIPK3 complex. Gene set enrichment analyses reveal that the MYC pathway is the most prominently down-regulated signaling pathway during necroptosis. Depletion or deletion of MYC promotes the RIPK1-RIPK3 interaction, thereby stabilizing the RIPK1 and RIPK3 proteins and facilitating necroptosis. Interestingly, MYC binds to RIPK3 in the cytoplasm and inhibits the interaction between RIPK1 and RIPK3 in vitro. Furthermore, MYC-nick, a truncated form that is mainly localized in the cytoplasm, prevented TNF-induced necroptosis. Finally, down-regulation of MYC enhances necroptosis in leukemia cells and suppresses tumor growth in a xenograft model upon treatment with birinapant and emricasan. MYC-mediated suppression of necroptosis is a mechanism of necroptosis resistance in cancer, and approaches targeting MYC to induce necroptosis represent an attractive therapeutic strategy for cancer
Tenofovir disoproxil fumarate monotherapy for nucleos(t)ide analogue-naïve and nucleos(t)ide analogue-experienced chronic hepatitis B patients
Background/AimsThis study investigated the antiviral effects of tenofovir disoproxil fumarate (TDF) monotherapy in nucleos(t)ide analogue (NA)-naive and NA-experienced chronic hepatitis B (CHB) patients.MethodsCHB patients treated with TDF monotherapy (300 mg/day) for ≥12 weeks between December 2012 and July 2014 at a single center were retrospectively enrolled. Clinical, biochemical, and virological parameters were assessed every 12 weeks.ResultsIn total, 136 patients (median age 49 years, 96 males, 94 HBeAg positive, and 51 with liver cirrhosis) were included. Sixty-two patients were nucleos(t)ide (NA)-naïve, and 74 patients had prior NA therapy (NA-exp group), and 31 patients in the NA-exp group had lamivudine (LAM)-resistance (LAM-R group). The baseline serum hepatitis B virus (HBV) DNA level was 4.9±2.3 log IU/mL (mean±SD), and was higher in the NA-naïve group than in the NA-exp and LAM-R groups (5.9±2.0 log IU/mL vs 3.9±2.0 log IU/mL vs 4.2±1.7 log IU/mL, P<0.01). The complete virological response (CVR) rate at week 48 in the NA-naïve group (71.4%) did not differ significantly from those in the NA-exp (71.3%) and LAM-R (66.1%) groups. In multivariate analysis, baseline serum HBV DNA was the only predictive factor for a CVR at week 48 (hazard ratio, 0.809; 95% confidence interval, 0.729-0.898), while the CVR rate did not differ with the NA experience.ConclusionsTDF monotherapy was effective for CHB treatment irrespective of prior NA treatment or LAM resistance. Baseline serum HBV DNA was the independent predictive factor for a CVR
Korea HIV/AIDS Cohort Study: study design and baseline characteristics
The number of persons infected by HIV/AIDS has consistently increased in Korea since the first case of HIV/AIDS infection in 1985 and reached 15,208 by 2016. About 1,100 new patients with HIV/ AIDS infections have emerged every year since 2013. In Korea, the Korea HIV/AIDS Cohort Study was established for the evidenced-based prevention, treatment, and effective management of patients infected with human immunodeficiency virus (HIV) in December 2006. This study monitored 1,438 patients, who accounted for about 10% of all patients with HIV/AIDS in Korea, for 10 years with the following aims: (1) to develop an administrative system for the establishment of a HIV/AIDS cohort-based study; (2) to standardize methodologies and the case report forms; and (3) to standardize multi-cohort data and develop a data cleaning method. This study aims to monitor at least 1,000 patients (excluding those for whom investigation had been completed) per year (estimated number of patients who can be monitored by January 2018: 939). By December 2016, the sex distribution was 93.3% for men, and 6.7% for women (gender ratio, 13.9:1.0), and 98.9% of all participants were Korean. More than 50.0% of the participants were confirmed as HIV positive after 2006. This study reports competitive, long-term research that aimed to develop policies for the prevention of chronic infectious diseases for patients with HIV. The data collected over the last decade will be used to develop indices for HIV treatment and health promotion
Erratum: Global, regional, and national comparative risk assessment of 84 behavioural, environmental and occupational, and metabolic risks or clusters of risks for 195 countries and territories, 1990–2017: a systematic analysis for the Global Burden of Disease Study 2017
Interpretation: By quantifying levels and trends in exposures to risk factors and the resulting disease burden, this assessment offers insight into where past policy and programme efforts might have been successful and highlights current priorities for public health action. Decreases in behavioural, environmental, and occupational risks have largely offset the effects of population growth and ageing, in relation to trends in absolute burden. Conversely, the combination of increasing metabolic risks and population ageing will probably continue to drive the increasing trends in non-communicable diseases at the global level, which presents both a public health challenge and opportunity. We see considerable spatiotemporal heterogeneity in levels of risk exposure and risk-attributable burden. Although levels of development underlie some of this heterogeneity, O/E ratios show risks for which countries are overperforming or underperforming relative to their level of development. As such, these ratios provide a benchmarking tool to help to focus local decision making. Our findings reinforce the importance of both risk exposure monitoring and epidemiological research to assess causal connections between risks and health outcomes, and they highlight the usefulness of the GBD study in synthesising data to draw comprehensive and robust conclusions that help to inform good policy and strategic health planning
Aerospace Integrated Research Systems
Recently, people move their interest from
developing single middleware to integration of those
middleware and operations. One way to integrate Grid
middleware and provide easy to use environment to
application research scientists is using a portal. In this
paper, we will discuss how to develop a wind tunnel
simulation service that will be used by aerospace
community by using this portal technology.
Two main philosophies of such architecture are
reusability and user-friendliness. Each part of our
system can be re-used without any major difficulties.
And since we have developed this system user in mind
we try to make as easy as possible to use. Aerospace
research scientists are actively involved from the
beginning when we design overall architecture and
design user interface of each step.OAIID:oai:osos.snu.ac.kr:snu2006-01/104/0000004648/59SEQ:59PERF_CD:SNU2006-01EVAL_ITEM_CD:104USER_ID:0000004648ADJUST_YN:NEMP_ID:A001138DEPT_CD:446CITE_RATE:0FILENAME:04021110.pdfDEPT_NM:기계항공공학부EMAIL:[email protected]:
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