27 research outputs found

    Czochralski growth techniques of germanium crystals grown from a melt covered partially or fully by liquid B2O3

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    We propose two unique Czochralski (CZ) techniques for growing germanium (Ge) crystals with an extremely low dislocation density and high interstitial oxygen concentration ([Oi]) using boron oxide (B2O3) and a silica crucible. When a Ge melt is partially covered with liquid B2O3, but only on the outer region of the melt surface, germanium-oxide (GeO2)-related particles forming naturally in the melt are effectively dissolved by the liquid B2O3. The clean central portion of the melt produces dislocation-free undoped or Ga-doped Ge crystals. In addition, Ge crystals with [Oi] up to 6 x 10(17) cm(-3) can be grown from a melt fully covered by liquid B2O3 with added GeO2 powder. The reaction and transportation of oxygen atoms during the growth process using B2O3 was investigated, revealing that liquid B2O3 acts like a catalyst without heavy contamination of the growing Ge crystal by B and Si atoms. (C) 2011 Elsevier B.V. All rights reserved.JOURNAL OF CRYSTAL GROWTH. 360:47-51 (2012)journal articl

    Czochralski-growth of germanium crystals containing high concentrations of oxygen impurities

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    Oxygen-containing germanium (Ge) single crystals with low density of grown-in dislocations were grown by the Czochralski (CZ) technique from a Ge melt, both with and without a covering by boron oxide (B(2)O(3)) liquid. Interstitially dissolved oxygen concentrations in the crystals were determined by the absorption peak at 855 cm(-1) in the infrared absorption spectra at room temperature. It was found that oxygen concentration in a Ge crystal grown from melt partially or fully covered with B(2)O(3) liquid was about 10(16) cm(-3) and was almost the same as that in a Ge crystal grown without B(2)O(3). Oxygen concentration in a Ge crystal was enhanced to be greater than 10(17) cm(-3) by growing a crystal from a melt fully covered with B(2)O(3); with the addition of germanium oxide powder, the maximum oxygen concentration achieved was 5.5 x 10(17) cm(-3). The effective segregation coefficients of oxygen in the present Ge crystal growth were roughly estimated to be between 1.0 and 1.4.ArticleJOURNAL OF CRYSTAL GROWTH. 312(19):2783-2787 (2010)journal articl

    Plasma brain natriuretic peptide as a surrogate marker for cardioembolic stroke

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    <p>Abstract</p> <p>Background</p> <p>Cardioembolic stroke generally results in more severe disability, since it typically has a larger ischemic area than the other types of ischemic stroke. However, it is difficult to differentiate cardioembolic stroke from non-cardioembolic stroke (atherothrombotic stroke and lacunar stroke). In this study, we evaluated the levels of plasma brain natriuretic peptide in acute ischemic stroke patients with cardioembolic stroke or non-cardioembolic stroke, and assessed the prediction factors of plasma brain natriuretic peptide and whether we could differentiate between stroke subtypes on the basis of plasma brain natriuretic peptide concentrations in addition to patient's clinical variables.</p> <p>Methods</p> <p>Our patient cohort consisted of 131 consecutive patients with acute cerebral infarction who were admitted to Kagawa University School of Medicine Hospital from January 1, 2005 to December 31, 2007. The mean age of patients (43 females, 88 males) was 69.6 ± 10.1 years. Sixty-two patients had cardioembolic stroke; the remaining 69 patients had non-cardioembolic stroke (including atherothrombotic stroke, lacunar stroke, or the other). Clinical variables and the plasma brain natriuretic peptide were evaluated in all patients.</p> <p>Results</p> <p>Plasma brain natriuretic peptide was linearly associated with atrial fibrillation, heart failure, chronic renal failure, and left atrial diameter, independently (F<sub>4,126 </sub>= 27.6, p < 0.0001; adjusted R<sup>2 </sup>= 0.45). Furthermore, atrial fibrillation, mitral regurgitation, plasma brain natriuretic peptide (> 77 pg/ml), and left atrial diameter (> 36 mm) were statistically significant independent predictors of cardioembolic stroke in the multivariable setting (Χ<sup>2 </sup>= 127.5, p < 0.001).</p> <p>Conclusion</p> <p>It was suggested that cardioembolic stroke was strongly predicted with atrial fibrillation and plasma brain natriuretic peptide. Plasma brain natriuretic peptide can be a surrogate marker for cardioembolic stroke.</p

    Design and baseline characteristics of the finerenone in reducing cardiovascular mortality and morbidity in diabetic kidney disease trial

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    Background: Among people with diabetes, those with kidney disease have exceptionally high rates of cardiovascular (CV) morbidity and mortality and progression of their underlying kidney disease. Finerenone is a novel, nonsteroidal, selective mineralocorticoid receptor antagonist that has shown to reduce albuminuria in type 2 diabetes (T2D) patients with chronic kidney disease (CKD) while revealing only a low risk of hyperkalemia. However, the effect of finerenone on CV and renal outcomes has not yet been investigated in long-term trials. Patients and Methods: The Finerenone in Reducing CV Mortality and Morbidity in Diabetic Kidney Disease (FIGARO-DKD) trial aims to assess the efficacy and safety of finerenone compared to placebo at reducing clinically important CV and renal outcomes in T2D patients with CKD. FIGARO-DKD is a randomized, double-blind, placebo-controlled, parallel-group, event-driven trial running in 47 countries with an expected duration of approximately 6 years. FIGARO-DKD randomized 7,437 patients with an estimated glomerular filtration rate >= 25 mL/min/1.73 m(2) and albuminuria (urinary albumin-to-creatinine ratio >= 30 to <= 5,000 mg/g). The study has at least 90% power to detect a 20% reduction in the risk of the primary outcome (overall two-sided significance level alpha = 0.05), the composite of time to first occurrence of CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure. Conclusions: FIGARO-DKD will determine whether an optimally treated cohort of T2D patients with CKD at high risk of CV and renal events will experience cardiorenal benefits with the addition of finerenone to their treatment regimen. Trial Registration: EudraCT number: 2015-000950-39; ClinicalTrials.gov identifier: NCT02545049

    Czochralski growth techniques of germanium crystals grown from a melt covered partially or fully by liquid B2O3

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    We propose two unique Czochralski (CZ) techniques for growing germanium (Ge) crystals with an extremely low dislocation density and high interstitial oxygen concentration ([Oi]) using boron oxide (B2O3) and a silica crucible. When a Ge melt is partially covered with liquid B2O3, but only on the outer region of the melt surface, germanium-oxide (GeO2)-related particles forming naturally in the melt are effectively dissolved by the liquid B2O3. The clean central portion of the melt produces dislocation-free undoped or Ga-doped Ge crystals. In addition, Ge crystals with [Oi] up to 6 x 10(17) cm(-3) can be grown from a melt fully covered by liquid B2O3 with added GeO2 powder. The reaction and transportation of oxygen atoms during the growth process using B2O3 was investigated, revealing that liquid B2O3 acts like a catalyst without heavy contamination of the growing Ge crystal by B and Si atoms. (C) 2011 Elsevier B.V. All rights reserved.JOURNAL OF CRYSTAL GROWTH. 360:47-51 (2012)journal articl
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