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Percutaneous coronary intervention in patients with peripheral artery disease and adverse cardiovascular adverse event and bleeding. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.1149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Peripheral artery disease (PAD) increase the risk of comorbidity and mortality in coronary artery disease (CAD).
Objectives
We evaluate influence of PAD on prognosis in patients undergoing percutaneous coronary intervention (PCI).
Methods
We analyzed all consecutive patients included in our dedicated local registry for PCI between January 2011 and December 2016. Presence of PAD was defined by decreased ankle-brachial index (<0.9). Major adverse cardiovascular event (MACE) was defined as a composite of cardiovascular death, non-fatal myocardial infarct, revascularization, and ischemic stroke. Major bleeding was defined as Bleeding Academic Research Consortium 3 or 5.
Results
Among the 4,747 patients who underwent the PCI, 12.9% (n=610) of PAD were identified. Old age (>60 years), renal dysfunction, reduced ejection fraction, and presence of PAD were predictors with both MACE and major bleeding event. Among them, presence of PAD was an independent risk factor of MACE and major bleeding (MACE, HR 8.26, 95% CI 2.33- 29.41, p=0.036; major bleeding, HR 3.11, 95% CI 1.10–10.63, p=0.040, respectively). The MACE and major bleeding rate at 5-year was significantly increased in patients with PAD (MACE, 30.0% vs. 15.8%, log rank test p<0.001; major bleeding, 6.7 vs. 3.6%, log rank test p=0.003, respectively) (Figure).
Conclusion
Presence of PAD was strongly associated with higher rate of long-term MACE and major bleeding. These findings could have a clinical relevance in requiring individualized pharmacologic strategies to reduce the burden of cardiovascular disease.
Funding Acknowledgement
Type of funding sources: None.
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Impact of active and stable cancer on survival in patients undergoing percutaneous coronary intervention. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.2858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
With advances in treatment of ischemic heart disease and cancer treatment, use of percutaneous coronary intervention (PCI) in cancer survivors and patients with active cancer (AC) is expanding.
Objectives
The purpose of this study was to determine the impact of cancer on survival and major cardiovascular events (MACE) in a long-term, single-center cohort of patients treated with PCI.
Methods
Patients treated with PCI between January 2010 and December 2017 were grouped as follows: controls (patients without cancer), stable cancer (SC), and AC. AC was included patients with cancer diagnosed within the past 6 months, patients who had cancer-related therapy within the past 6 months, active metastatic disease, or active recurrence of the cancer. The primary endpoints were 5-year survival and a secondary endpoint was 5-year MACE.
Results
A total of 6,743 patients (age 66±12 years, 68.4% men) treated with PCI were included: 6,404 (95.0%) controls, 245 (3.6%) SC, and 94 (1.4%) AC. Predominant malignancies were gastrointestinal (37.4%), lung (22.7%), and genitourinary cancer (14.7%). No differences were observed between patients with AC, SC and controls regarding 5-year MACE (total MACE, 33.2% vs. 28.1% vs. 17.5%, p=0.072; cardiac death, 13.6% vs. 9.1% vs. 6.7%, p=0.066; non-fatal myocardial infarction, 2.9% vs. 7.5% vs. 7.8%, p=0.820; revascularization, 17.9% vs. 17.6% vs. 11.6%, p=0.794, respectively). Patients with AC and SC had reduced 5-year survival compared with controls (62.0% vs. 81.5% vs. 89.8%, p<0.001) (Figure). AC was associated with a 1.76 (95% CI 1.22 to 2.54, p=0.002) fold increased risk of all-cause 5-year mortality in multivariable adjusted models.
Conclusions
Cumulative incidence of 5-year survival was discriminated by concurrent status of cancer following PCI. Individualized decision making is needed in the routine practice of PCI regarding concurrent cancer-specific treatment and prognosis.
Funding Acknowledgement
Type of funding sources: None.
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P1416 Clinical importance of consecutive transthoracic echocardiography in the patients with hypertrophic cardiomyopathy. Eur Heart J Cardiovasc Imaging 2020. [DOI: 10.1093/ehjci/jez319.848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Funding Acknowledgements
nothing
OnBehalf
nothing
Background
prediction of outcomes Hypertrophic cardiomyopathy (HCM) have been robustly analyzed with echocardiography. However, there is limited data of serial follow-up (FU) transthoracic echocardiography (TTE) to predict outcomes in patients with HCM.
Objectives
This study aim is to discover clinical predictors associated with consecutive TTE follow-up in patients with HCM.
Methods
From 2010 to 2016, 162 patients with HCM were enrolled retrospectively. Concentric LVH and others systolic disease related to wall thickness were excluded. Index TTE (baseline) was measured when firstly admitted in our hospital. FU TTE was analyzed at the end of follow-up, defined as the last recorded value in patients who did not develop events or the last recorded value before events developed.
Results
The average of FU TTE and clinical FU period was 3.7 ± 2.0 years. Clinical outcomes were defined as stroke, syncope, heart failure, arrhythmia and death. Interestingly, only baseline TR V max was a predictor for clinical outcome whereas the others echo parameters were not associated with events (Table 1). KM curve showed the TR Vmax ≥2.5m/s was also significant (log rank = 0.008, Fig 1.)
Conclusions Our study showed short-term FU TTE did not bring clinician with clinical benefits in the aspect of prediction for events. Only baseline TR V max was good correlation with cardiovascular outcomes and even in the survival analysis.
Serial TTE and changed values Total N = 162 index TTE (baseline) FU TTE Change of FU per year event no event p-value event no event p-value event no event p-value IVDd, mm 14 ± 4 15 ± 5 0.500 15 ± 5 14 ± 5 0.758 0.23 ± 0.51 -0.07 ± 1.27 0.200 LVIDd, mm 47 ± 5 48 ± 6 0.256 47 ± 7 48 ± 6 0.560 -0.22 ± 2.79 0.10 ± 2.27 0.444 LVEF, % 62 ± 5 61 ± 7 0.379 61 ± 6 61 ± 10 0.927 -0.43 ± 3.10 -0.04 ± 4.94 0.620 LAVI 43 ± 9 43 ± 8 0.879 57 ± 27 58 ± 23 0.849 0.53 ± 14.5 3.11 ± 7.2 0.134 EA ratio 0.9 ± 0.6 0.9 ± 0.6 0.782 1.0 ± 0.8 0.9 ± 0.6 0.595 -0.02 ± 0.76 0.003 ± 0.027 0.594 DT,ms 196 ± 58 201 ± 62 0.603 203 ± 91 217 ± 89 0.370 17 ± 57 5 ± 40 0.154 septal e` 4.4 ± 2.1 4.2 ± 1.6 0.585 4.4 ± 1.6 4.6 ± 1.7 0.438 0.24 ± 0.91 0.05 ± 0.65 0.190 E of e` 17 ± 11 17 ± 23 0.993 15 ± 9 15 ± 6 0.726 -0.48 ± 4.42 -1.66 ± 22.78 0.728 TR velocity 2.6 ± 0.5 2.4 ± 0.4 0.012 2.7 ± 0.6 2.6 ± 0.4 0.604 0.05 ± 0.30 0.04 ± 0.18 0.905 Max wall thickness 17 ± 3 18 ± 3 0.137 17 ± 4 17 ± 3 0.888 -0.01 ± 2.19 -0.18 ± 1.14 0.522
Abstract P1416 Figure. TR Vmax and CV outcomes in the KM curve
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P3637Relationship between serial measurements of NT-proBNP and cardiovascular events in patients with acute coronary syndrome. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz745.0494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Increased level of natriuretic peptides has been known as an important predictors of adverse cardiovascular (CV) outcomes in patients with acute coronary syndrome (ACS). We sought to evaluate clinical implication of N-terminal pro-brain natriuretic peptide (NT-proBNP) measured at initial and follow-up periods.
Methods
Serial NT-proBNP levels (on-admission and one-month post-PCI) were measured in ACS patients undergoing PCI (n=2,290). High NT-proBNP levels were determined according to the predefined age-specific criteria. Patients were stratified into 4 groups according to NT-proBNP levels (on-admission & one-month): (1) normal-normal group (n=1234, 53.9%); (2) high–normal group (n=257, 11.2%); (3) normal-high group (n=376, 16.4%); and (4) high-high group (n=423, 18.5%). Clinical events were defined as all-cause death and MACE (a composite of CV death, non-fatal MI, and ischemic stroke).
Results
With a median follow-up of 35.9 (IQR: 16.8, 54.5) months, all-cause death and MACE were occurred in 4.1% and 7.2%, respectively. NT-proBNP on-admission vs. at one-month did not differ significantly (median 391.6 [IQR: 143.9, 1402.3] vs. median 619.1 [IQR 240.1, 1616.1]; p=0.622), but the prevalence of high NT-proBNP was increased over time (25.3% to 34.9%; p<0.001). The rates of all-cause death and MACE significantly increased only in the high-high group compared with other groups (log-rank test, all p values <0.001, Figure). After adjustment, the high-high group remained significantly risky in terms with the occurrence of all-cause death (HR, 2.99; 95% CI, 1.65 to 5.41; p<0.001) and MACE (HR, 1.96; 95% CI, 1.28 to 3.01; p=0.002).
Figure 1
Conclusion
Serial measurements of NT-proBNP at on-admission and follow-up can help to stratify the risks of all-cause death and adverse CV events following PCI in ACS patients. About two-fifths of patients having high NT-proBNP level during hospitalization can be classified into the low-risk group for all-cause death and adverse CV events.
Acknowledgement/Funding
None
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Abstract
Sarcopenia, defined as loss of skeletal muscle mass and function with age, is an important health issue in aging society. We tried to investigate the relationship between blood pressure variability and skeletal muscle mass in nation-wide large population cohort. This cross-sectional study was based on data acquired in the Korea National Health and Nutrition Examination Survey (KNHANES), conducted from 2009 to 2011 by the Korean Centers for Disease Control and Prevention. We included 14,481 participants (age ≥ 20 years, male 6,302) for the analysis who had both blood pressure and whole-body dual energy X-ray absorptiometry (DXA) scan data. As an intra-individual within-visit blood pressure variability index, we calculated standard deviation (SD), coefficient of variation (CV), and maximum minus minimum BP difference (MMD) of systolic and diastolic blood pressure, which was measured 3 times. Appendicular skeletal muscle mass (ASM) was the sum of lean masses of both arms and legs. We adjusted ASM by body mass index. Significant inverse relationship was observed between blood pressure variability index (SD, CV, and MMD) and adjusted ASM. Blood pressure variability index were significantly higher in the lowest ASM quintile group both in male and female participants (p<0.001). In multivariate analysis, blood pressure variability index were significantly associated with ASM, even after adjusting confounding factors (p<0.001). In conclusion, hemodynamic influence may play an important role in the development of sarcopenia.
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P3681Syntax-I score can predict in-hospital mortality among the patients with ST segment elevation myocardial infarction and cardiogenic shock. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy563.p3681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Staphylococcal enterotoxin IgE sensitization in late-onset severe eosinophilic asthma in the elderly. Clin Exp Allergy 2016; 46:411-21. [PMID: 26436720 DOI: 10.1111/cea.12652] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Revised: 09/08/2015] [Accepted: 09/10/2015] [Indexed: 12/15/2022]
Abstract
BACKGROUND Asthma in the elderly (aged ≥ 65 years old) is a significant concern with high morbidity, but the pathophysiology remains unclear particularly in late-onset asthma. Recent studies suggest staphylococcal enterotoxin IgE (SE-IgE) sensitization to be a risk factor for asthma in general populations; however, the associations have not been examined in late-onset elderly asthma. OBJECTIVE We aimed to examine the associations of SE-IgE sensitization with late-onset asthma in the elderly, using a database of elderly asthma cohort study. METHODS A total of 249 elderly patients with asthma and 98 controls were analysed. At baseline, patients were assessed for demographics, atopy, induced sputum profiles and comorbidities including chronic rhinosinusitis (CRS). Serum total IgE and SE-IgE levels were measured. Asthma severity was assessed on the basis of asthma outcomes during a 12-month follow-up period. RESULTS At baseline, serum SE-IgE concentrations were significantly higher in patients with asthma than in controls [median 0.16 (interquartile range 0.04-0.53) vs. 0.10 (0.01-0.19), P < 0.001]. Elderly asthma patients with high SE-IgE levels had specific characteristics of having more severe asthma, sputum eosinophilia and CRS, compared to those with lower SE-IgE levels. In multivariate logistic regression analyses, the associations between serum SE-IgE concentrations and severe asthma were significant, independently of covariables [SE-IgE-high (≥ 0.35 kU/L) vs. negative (< 0.10 kU/L) group: odds ratio 7.47, 95% confidence interval 1.86-30.03, P = 0.005]. Multiple correspondence analyses also showed that high serum SE-IgE level had close relationships with severe asthma, CRS and sputum eosinophilia together. CONCLUSIONS AND CLINICAL RELEVANCE This is the first report on the significant associations of SE-IgE sensitization with late-onset asthma in the elderly, particularly severe eosinophilic asthma with CRS comorbidity. Our findings indicate a potential implication of SE in the high morbidity burden of elderly asthma and suggest clues to the pathogenesis of severe late-onset eosinophilic asthma in the elderly.
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A Study of Piezoelectric Field Related Strain Difference in GaN-Based Blue Light-Emitting Diodes Grown on Silicon(111) and Sapphire Substrates. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2016; 16:1798-1801. [PMID: 27433673 DOI: 10.1166/jnn.2016.11939] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We investigate the strain difference in InGaN/GaN multiple quantum wells of blue light-emitting diode (LED) structures grown on silicon(1 11) and c-plane sapphire substrates by comparing the strength of piezo-electric fields in MQWs. The piezo-electric fields for two LED samples grown on silicon and sapphire substrates are measured by using the reverse-bias electro-reflectance (ER) spectroscopy. The flat-band voltage is obtained by measuring the applied reverse bias voltage that induces a phase inversion in the ER spectra, which is used to calculate the strength of piezo-electric fields. The piezo-electric field is determined to be 1.36 MV/cm for the LED on silicon substrate and 1.83 MV/cm for the LED on sapphire substrate. The ER measurement results indicate that the strain-induced piezo-electric field is greatly reduced in the LED grown on silicon substrates consistent with previous strain measurement results by micro-Raman spectroscopy and high-resolution transmission electron microscopy.
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Comparison of Strain in GaN-Based Blue Light-Emitting Diode Grown on Silicon(111) and Sapphire Substrates. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2015; 15:5264-5266. [PMID: 26373120 DOI: 10.1166/jnn.2015.10408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We compare the strain states and device performances of GaN-based blue light-emitting diodes (LEDs) grown on Si(111) and sapphire substrates. The strain characteristics are investigated using micro-Raman spectroscopy and high-resolution transmission electron microscopy. These analyses reveal that GaN layer grown on Si has a residual tensile strain in contrast to a compressive strain for GaN on sapphire, and quantum wells (QWs) on GaN/Si experience reduced lattice mismatch than those of GaN/sapphire. When external quantum efficiencies of LED on sapphire and Si substrates are compared, the LED on Si shows better efficiency droop characteristics and this is attributed to a decrease in piezo-electric field strength in InGaN/GaN layers owing to reduced lattice mismatch.
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Two cases of cytarabine syndrome successfully resolved by desensitization. J Investig Allergol Clin Immunol 2015; 25:80-82. [PMID: 25898709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023] Open
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11
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Tuning the Fano resonance with an intruder continuum. NANO LETTERS 2014; 14:788-793. [PMID: 24460187 DOI: 10.1021/nl404133d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Through a combination of experiment and theory we establish the possibility of achieving strong tuning of Fano resonances (FRs), by allowing their usual two-path geometry to interfere with an additional, "intruder", continuum. As the coupling strength to this intruder is varied, we predict strong modulations of the resonance line shape that, in principle at least, may exceed the amplitude of the original FR itself. For a proof-of-concept demonstration of this phenomenon, we construct a nanoscale interferometer from nonlocally coupled quantum point contacts and utilize the unique features of their density of states to realize the intruder. External control of the intruder coupling is enabled by means of an applied magnetic field, in the presence of which we demonstrate the predicted distortions of the FR. This general scheme for resonant control should be broadly applicable to a variety of wave-based systems, opening up the possibility of new applications in areas such as chemical and biological sensing and secure communications.
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Insulator, semiclassical oscillations and quantum Hall liquids at low magnetic fields. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:405601. [PMID: 22968955 DOI: 10.1088/0953-8984/24/40/405601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Magneto-transport measurements are performed on two-dimensional GaAs electron systems to probe the quantum Hall (QH) effect at low magnetic fields. Oscillations following the Shubnikov-de Haas (SdH) formula are observed in the transition from the insulator to QH liquid when the observed almost temperature-independent Hall slope indicates insignificant interaction correction. Our study shows that the existence of SdH oscillations in such a transition can be understood based on the non-interacting model.
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Severe drug hypersensitivity induced by erdosteine and doxofylline as confirmed by patch and lymphocyte transformation tests: a case report. J Investig Allergol Clin Immunol 2012; 22:230-232. [PMID: 22697021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023] Open
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Fabrication and radio frequency characterization of carbon nanotube field effect transistor: evidence of quantum capacitance. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2011; 11:7222-7225. [PMID: 22103162 DOI: 10.1166/jnn.2011.4834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We fabricated an radio frequency (RF) carbon nanotube field effect transistor (CNTFET) whose electrode shapes were standard RF designed ground-signal-ground (GSG)-type pads. The S-parameters measured from our RF CNTFET in the frequency range up to 6 GHz were fitted with an RF equivalent circuit, and the extracted gate capacitance was shown to be the capacitance value of the series combination of the electrostatic capacitance and the quantum capacitance. The effect of the channel resistance and the kinetic inductance was also discussed.
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Association between levels of physical activity and poor self-rated health in Korean adults: The Third Korea National Health and Nutrition Examination Survey (KNHANES), 2005. Public Health 2009; 123:665-9. [PMID: 19854457 DOI: 10.1016/j.puhe.2009.08.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2009] [Revised: 08/13/2009] [Accepted: 08/23/2009] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To investigate the association between level of physical activity and poor self-rated health in Korean adults. STUDY DESIGN A cross-sectional study was conducted on 7,800 adults aged > or =19 years who completed the Health Interview and the Health Behavior Surveys, issued during the Third National Health and Nutrition Examination Survey (2005). METHODS The association between self-rated health and physical activity was tested using Chi-squared test. Multiple logistic regression analysis was used to calculate the odds ratios of poor self-rated health for different levels of physical activity after adjusting for physical and chronic medical conditions. RESULTS The prevalence of poor self-rated health was significantly lower as the level of physical activity increased, and odds ratios for poor self-rated health were significantly lower for higher levels of physical activity after adjusting for age, marital status, educational status, smoking, alcohol consumption, and the number of physical impairments and chronic medical conditions. The association was similar in different age groups and among healthy respondents and respondents with physical impairments or chronic medical conditions. CONCLUSIONS Physical activity was positively associated with self-rated health in Koreans. The independent association between a lower level of physical activity and poor self-rated health supports public health programmes that encourage regular physical activity.
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Fabrication of one-dimensional devices by a combination of AC dielectrophoresis and electrochemical deposition. NANOTECHNOLOGY 2008; 19:105305. [PMID: 21817698 DOI: 10.1088/0957-4484/19/10/105305] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We demonstrate a hybrid process for fabricating one-dimensional wire devices. The process is a combination of an alignment procedure using dielectrophoresis and subsequent contact metal formation utilizing electrochemical deposition with non-toxic organic-based Au electrolytes. Several devices have been successfully made from GaN nanowires or multi-walled carbon nanotubes (MWCNTs) using our hybrid technique. We demonstrate that rapid thermal annealing improves the ohmic characteristics by five orders of magnitude in the case of the GaN devices and ∼300% in the case of the MWCNT devices. One of the reasons for this improvement is enhanced gold wetting due to the reduction of grain size at the annealing temperature.
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Morphological and photoelectrochemical characterization of core-shell nanoparticle films for dye-sensitized solar cells: Zn-O type shell on SnO2 and TiO2 cores. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:4246-53. [PMID: 15969424 DOI: 10.1021/la036122x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Core-shell type nanoparticles with SnO2 and TiO2 cores and zinc oxide shells were prepared and characterized by surface sensitive techniques. The influence of the structure of the ZnO shell and the morphology ofnanoparticle films on the performance was evaluated. X-ray absorption near-edge structure and extended X-ray absorption fine structure studies show the presence of thin ZnO-like shells around the nanoparticles at low Zn levels. In the case of SnO2 cores, ZnO nanocrystals are formed at high Zn/Sn ratios (ca. 0.5). Scanning electron microscopy studies show that Zn modification of SnO2 nanoparticles changes the film morphology from a compact mesoporous structure to a less dense macroporous structure. In contrast, Zn modification of TiO2 nanoparticles has no apparent influence on film morphology. For SnO2 cores, adding ZnO improves the solar cell efficiency by increasing light scattering and dye uptake and decreasing recombination. In contrast, adding a ZnO shell to the TiO2 core decreases the cell efficiency, largely owing to a loss of photocurrent resulting from slow electron transport associated with the buildup of the ZnO surface layer.
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Biochemical and biophysical evidence for gamma 2 subunit association with neuronal voltage-activated Ca2+ channels. J Biol Chem 2001; 276:32917-24. [PMID: 11441000 DOI: 10.1074/jbc.m100787200] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A novel gene (Cacng2; gamma(2)) encoding a protein similar to the voltage-activated Ca(2+) channel gamma(1) subunit was identified as the defective gene in the epileptic and ataxic mouse, stargazer. In this study, we analyzed the association of this novel neuronal gamma(2) subunit with Ca(2+) channels of rabbit brain, and the function of the gamma(2) subunit in recombinant neuronal Ca(2+) channels expressed in Xenopus oocytes. Our results showed that the gamma(2) subunit and a closely related protein (called gamma(3)) co-sedimented and co-immunoprecipitated with neuronal Ca(2+) channel subunits in vivo. Electrophysiological analyses showed that gamma(2) co-expression caused a significant decrease in the current amplitude of both alpha(1B)(alpha(1)2.2)-class (36.8%) and alpha(1A)(alpha(1)2.1)-class (39.7%) Ca(2+) channels (alpha(1)beta(3)alpha(2)delta). Interestingly, the inhibitory effects of the gamma(2) subunit on current amplitude were dependent on the co-expression of the alpha(2)delta subunit. In addition, co-expression of gamma(2) or gamma(1) also significantly decelerates the activation kinetics of alpha(1B)-class Ca(2+) channels. Taken together, these results suggest that the gamma(2) subunit is an important constituent of the neuronal Ca(2+) channel complex and that it down-regulates neuronal Ca(2+) channel activity. Furthermore, the gamma(2) subunit likely contributes to the fine-tuning of neuronal Ca(2+) channels by counterbalancing the effects of the alpha(2)delta subunit.
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Abstract
This study was conducted to integrate the results of previous studies which evaluated hypertension as a risk factor for cerebrovascular disorders (CVD) in Koreans. We retrieved the Korean literature using a manual search and the English literature using the MEDLINE database concerning the relationship between hypertension and CVD in Koreans from 1980 to 1997. The overall effect size of hypertension as a risk factor of CVD was represented by common odds ratio (OR). Before the integration of each effect size, a heterogeneity test and a sensitivity test was conducted. The materials were nine published epidemiologic studies with a total of 2,271 cases of CVD. The common ORs (95% confidence interval) of overall CVD, hemorrhagic CVD and ischemic CVD associated with hypertension were 4.10 (3.56-4.71), 6.56 (4.92-8.80) and 3.28 (2.77-3.90), respectively. Thus, the common OR of hemorrhagic CVD associated with hypertension was significantly higher than that of overall or ischemic CVD. This suggests that hypertension is an important risk factor for overall CVD and its subtypes in Koreans. Due to the lack of reliable prospective studies, however, longitudinal study is required in this area.
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Generalized interframe vertex-based shape encoding scheme for video sequences. IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 2000; 9:1667-1676. [PMID: 18262906 DOI: 10.1109/83.869178] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The efficiency of shape coding is an important problem concerning content-based image manipulations and object-based coding of the video sequences. In order to encode the shape information of an object, the boundary is approximated by a polygon which can be encoded with the smallest number of bits for maximum allowable distortion. The conventional boundary coding schemes, however, does not successfully remove the temporal redundancy of the video sequences. This paper proposes a new boundary encoding scheme by which the temporal redundancy between two successive frames is efficiently removed, resulting in lower bit-rate than the conventional algorithms. The interframe vertex selection problem is solved by finding the path with the minimum cost in the directed acyclic graph (DAG) and its fast version using a simplified graph is introduced to reduce the computational load. The vertices were selected from both the current frame to be encoded and the previous frame already encoded, and thus, the temporal redundancy was effectively removed.
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Adaptive approximation bounds for vertex based contour encoding. IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 1999; 8:1142-1147. [PMID: 18267531 DOI: 10.1109/83.777097] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
When approximating the shape of a region, a fixed bound on the tolerable distortion is set for approximating its contour points. An adaptive approximation bound for lossy coding of the contour points is proposed. A function representing the relative significance of the contour points is defined to adjust the distortion bound along the region contour allowing an adaptive approximation of the region shape. The effectiveness of the adaptive contour coding approach for a region-based coding system is verified through experiments.
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Raf-1 kinase, a potential regulator of intracellular pH in Xenopus oocytes. Biol Cell 1998; 90:477-85. [PMID: 9923073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Xenopus laevis oocytes undergo an increase in intracellular pH (pHi) from 7.2 to 7.7 due to the up-regulation of Na+/H+ antiporters in their plasma membrane during oocyte meiotic maturation. Up-regulation of Na+/H+ exchangers (NHE) found in other cell systems appears to be controlled, in some cases, by direct phosphorylation of the exchanger. A number of active protein kinases can be found in maturing Xenopus oocytes. These include, c-mos kinase, Raf-1 kinase, mitogen-activated kinase kinase (MAPKK), MAPK, ribosomal S6 kinase (RSK), and histone H-1 kinase. Our previous study indicated that c-mos kinase, was involved in regulating the increase in oocyte pHi. In the current study, we show that when mRNA coding for a constitutively active form of Raf-1 kinase (delta N-Raf-1) was microinjected into oocytes, the protein product induced an increase in oocyte pHi. On the contrary, the injection of mRNA coding for wild-type Raf-1 (WT-Raf-1) or a kinase-deficient form of Raf-1 (KD-Raf-1) had no effect on the recipient oocyte pHi. 8-Br-cAMP and forskolin blocked the increase in pHi during oocyte meiotic maturation, but had no effect on the Raf-1-induced increase in oocyte pHi. Studies using antisense c-mos oligos demonstrated that Raf-1 was not working via a feedback loop to endogenous c-mos mRNA within the recipient oocytes. Experiments using the selective MAPKK inhibitor, PD 98059, indicated that the Raf-1 effect on oocyte pHi was not mediated by the downstream kinase, MAPKK. Therefore, Raf-1 appears to act independently of c-mos kinase in a pathway, not involving MAPKK, leading to the up-regulation of the Na+/H+ antiporters in Xenopus oocytes.
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A new mouse gene, SRG3, related to the SWI3 of Saccharomyces cerevisiae, is required for apoptosis induced by glucocorticoids in a thymoma cell line. J Exp Med 1997; 185:1827-36. [PMID: 9151708 PMCID: PMC2196310 DOI: 10.1084/jem.185.10.1827] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/1997] [Revised: 03/17/1997] [Indexed: 02/04/2023] Open
Abstract
We isolated a new mouse gene that is highly expressed in thymocytes, testis, and brain. This gene, SRG3, showed a significant sequence homology to SWI3, a yeast transcriptional activator, and its human homolog BAF155. SRG3 encodes 1,100 amino acids and has 33-47% identity with SWI3 protein over three regions. The SRG3 protein contains an acidic NH2 terminus, a myb-like DNA binding domain, a leucine-zipper motif, and a proline- and glutamine-rich region at its COOH terminus. Rabbit antiserum raised against a COOH-terminal polypeptide of the SRG3 recognized a protein with an apparent molecular mass of 155 kD. The serum also detected a 170-kD protein that seems to be a mouse homologue of human BAF170. Immunoprecipitation of cell extract with the antiserum against the mouse SRG3 also brought down a 195-kD protein that could be recognized by an antiserum raised against human SWI2 protein. The results suggest that the SRG3 protein associates with a mouse SWI2. The SRG3 protein is expressed about three times higher in thymocytes than in peripheral lymphocytes. The expression of anti-sense RNA to SRG3 mRNA in a thymoma cell line, S49.1, reduced the expression level of the SRG3 protein, and decreased the apoptotic cell death induced by glucocorticoids. These results suggest that the SRG3 protein is involved in the glucocorticoid-induced apoptosis in the thymoma cell line. This implicates that the SRG3 may play an important regulatory role during T cell development in thymus.
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Simultaneous multichannel image restoration and estimation of the regularization parameters. IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 1997; 6:774-778. [PMID: 18282972 DOI: 10.1109/83.568936] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
In this correspondence, a constrained least-squares multichannel image restoration approach is proposed, in which no prior knowledge of the noise variance at each channel or the degree of smoothness of the original image is required. The regularization functional for each channel is determined by incorporating both within-channel and cross-channel information. It is shown that the proposed smoothing functional has a global minimizer.
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General choice of the regularization functional in regularized image restoration. IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 1995; 4:594-602. [PMID: 18290009 DOI: 10.1109/83.382494] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The determination of the regularization parameter is an important issue in regularized image restoration, since it controls the trade-off between fidelity to the data and smoothness of the solution. A number of approaches have been developed in determining this parameter. In this paper, a new paradigm is adopted, according to which the required prior information is extracted from the available data at the previous iteration step, i.e., the partially restored image at each step. We propose the use of a regularization functional instead of a constant regularization parameter. The properties such a regularization functional should satisfy are investigated, and two specific forms of it are proposed. An iterative algorithm is proposed for obtaining a restored image. The regularization functional is defined in terms of the restored image at each iteration step, therefore allowing for the simultaneous determination of its value and the restoration of the degraded image. Both proposed iteration adaptive regularization functionals are shown to result in a smoothing functional with a global minimum, so that its iterative optimization does not depend on the initial conditions. The convergence of the algorithm is established and experimental results are shown.
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