Study of Various Flow Regimes in the Water Intrusion Process into Porous Media under Different Upstream Boundary Conditions

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

Short- and Long-Term Observations of Fracture Permeability in Granite by Flow-Through Tests and Comparative Observation by X-Ray CT

Having a grasp of the variation in the fracture contact area is a kernel in the understanding of the permeability evolution of fractured rocks. However, the number of studies that focus on measuring the long-term variation in the fracture contact area under different conditions is insufficient. In this study, a series of short- and long-term permeability tests under coupled conditions is performed to check the performance of permeability. The results reveal that the permeability measured in the short-term tests shows reversible behavior and a dependence on the applied confining pressures and temperature. In contrast, the permeability in the long-term tests displays irreversible behavior and an irregular change under the constant confining pressure. In order to verify the evolution of permeability, microfocus X-ray computed tomography (CT) is developed to observe the changes in the internal fracture structure under the same conditions as those in long-term permeability tests by assembling a triaxial cell with heating capability. The fracture aperture and the fracture contact-area ratio are calculated by a CT image analysis technique. The image analysis results show that the estimated aperture is seen to decrease with an increase in the confining pressure and to also decrease with time under a constant confining pressure. Moreover, the increase in the fracture contact area under the constant confining pressure observed by X-ray CT is confirmed. This also corresponds to a decrease in permeability in long-term tests. The hydraulic aperture calculated from the permeability tests and that evaluated from the CT observation have a similar decreasing trend. Therefore, the CT observation can better capture the evolution of the internal fracture contact area. These experiments underscore the importance of mechanical compaction and/or mineral dissolution at contacts in determining the rates and the magnitude of permeability evolution within rock fractures

Reduced endogenous secretory RAGE in blood and bronchoalveolar lavage fluid is associated with poor prognosis in idiopathic pulmonary fibrosis

Background The endogenous secretory receptor for advanced glycation end products (esRAGE) is a soluble isoform produced by alternative splicing of the RAGE gene. The isoform has anti-inflammatory properties due to its inhibition of the RAGE/ligand interaction and is reduced in the lung tissue of patients with idiopathic pulmonary fibrosis (IPF). This study aimed to investigate the association of esRAGE serum and bronchoalveolar lavage fluid (BALF) levels with progression of IPF. Methods This study included 79 IPF patients and 90 healthy controls. IPF and control serum esRAGE levels were compared, and the correlation between serum and BALF esRAGE levels was analyzed in 57 IPF patient samples. We also investigated the relationship of esRAGE serum and BALF levels with prognoses and lung function parameters in patients with IPF. Results Serum esRAGE levels in IPF patients were significantly lower than those in healthy controls (162.0 +/- 102.4 ng/ml and 200.7 +/- 107.3 ng/ml,p = 0.009), although the baseline characteristics of age and smoking history were not matched. Serum levels of esRAGE were correlated with BALF esRAGE levels (r(s) = 0.317). The BALF esRAGE levels were also correlated with diffusion capacity for carbon monoxide (r(s) = 0.406). A Kaplan-Meier curve analysis and univariate/multivariate Cox hazard proportion analysis revealed that lower levels of esRAGE in blood and BALF were significantly associated with poorer prognoses in patients with IPF. Conclusions Decreased esRAGE levels in BALF and blood were associated with poor prognoses in patients with IPF. These results suggest that esRAGE could be related to the pathophysiology of IPF and serum esRAGE could be a potential prognostic marker of IPF.Peer reviewe

Fatty liver incidence and predictive variables.

Although fatty liver predicts ischemic heart disease, the incidence and predictors of fatty liver need examination. The objective of this study was to determine fatty liver incidence and predictive variables. Using abdominal ultrasonography, we followed biennially through 2007 (mean follow-up, 11.6+/-4.6 years) 1635 Nagasaki atomic bomb survivors (606 men) without fatty liver at baseline (November 1990 through October 1992). We examined potential predictive variables with the Cox proportional hazard model and longitudinal trends with the Wilcoxon rank-sum test. In all, 323 (124 men) new fatty liver cases were diagnosed. The incidence was 19.9/1000 person-years (22.3 for men, 18.6 for women) and peaked in the sixth decade of life. After controlling for age, sex, and smoking and drinking habits, obesity (relative risk (RR), 2.93; 95% confidence interval (CI), 2.33-3.69, P<0.001), low high-density lipoprotein-cholesterol (RR, 1.87; 95% CI, 1.42-2.47; P<0.001), hypertriglyceridemia (RR, 2.49; 95% CI, 1.96-3.15; P<0.001), glucose intolerance (RR, 1.51; 95% CI, 1.09-2.10; P=0.013) and hypertension (RR, 1.63; 95% CI, 1.30-2.04; P<0.001) were predictive of fatty liver. In multivariate analysis including all variables, obesity (RR, 2.55; 95% CI, 1.93-3.38; P<0.001), hypertriglyceridemia (RR, 1.92; 95% CI, 1.41-2.62; P<0.001) and hypertension (RR, 1.31; 95% CI, 1.01-1.71; P=0.046) remained predictive. In fatty liver cases, body mass index and serum triglycerides, but not systolic or diastolic blood pressure, increased significantly and steadily up to the time of the diagnosis. Obesity, hypertriglyceridemia and, to a lesser extent, hypertension might serve as predictive variables for fatty liver

sdLDL-C and Cardiovascular Events

Aim: There is little information on the relationships of serum small dense low-density lipoprotein cholesterol (sdLDL-C) levels and serum triglyceride (TG) levels with cardiovascular events in patients with coronary artery disease (CAD) and type 2 diabetes mellitus (DM) who are receiving statins. The aim of this study was to evaluate the relationships of serum TG levels and sdLDL-C levels as residual risks for cardiovascular events in patients with CAD and type 2 DM who were being treated with statins. Methods: The subjects were divided into four groups based on TG levels and sdLDL-C levels: sdLDL-C of ＜40.0 mg/dL and TG of ＜150 mg/dL, sdLDL-C of ≥ 40.0 mg/dL and TG of ＜150 mg/dL, sdLDL-C of ＜40.0 mg/dL and TG of ≥ 150 mg/dL, and sdLDL-C of ≥ 40.0 mg/dL and TG of ≥ 150 mg/dL. During a median follow-up period of 1419 days, cardiovascular events occurred in 34 patients. Results: The incidences of cardiovascular events were significantly higher in patients with sdLDL-C of ≥ 40.0 mg/dL and TG of ＜150 mg/dL and in patients with sdLDL-C of ≥ 40.0 mg/dL and TG of ≥ 150 mg/dL, but not in patients with sdLDL-C of ＜40.0 mg/dL and TG of ≥ 150 mg/dL, than in patients with sdLDL-C of ＜40.0 mg/dL and TG of ＜150 mg/dL. Conclusions: Under the condition of treatment with statins, patients with CAD and type 2 DM who had sdLDL-C levels of ≥ 40.0 mg/dL had a high risk for cardiovascular events even though serum TG levels were controlled at ＜150 mg/dL

Risk for Progression to Overt Hypothyroidism in an Elderly Japanese Population with Subclinical Hypothyroidism

Background: Few population-based studies report the changes with time in thyroid function tests in patients with subclinical hypothyroidism. We compared the risk for developing overt hypothyroidism in patients with subclinical hypothyroidism and euthyroid controls from the same population of elderly Japanese. We also sought associations of selected parameters with the development of overt hypothyroidism in the subclinical hypothyroid and euthyroid groups. Methods: We measured thyrotropin (TSH) and free thyroxine (T4) levels at baseline examinations performed from 2000 to 2003 in the cohort of Japanese atomic-bomb survivors and identified 71 patients with spontaneous subclinical hypothyroidism (normal free T4 and TSH >4.5 mIU/L without a history of thyroid treatment, mean age 70 year) and 562 euthyroid controls. We re-examined TSH and free T4 levels an average of 4.2 years later (range, 1.9-6.9). Results: The risk for progression to overt hypothyroidism was significantly increased in subclinical hypothyroid patients (7.0%) compared with control subjects (1.6%) after adjusting for age and sex (odds ratio, 4.56; p=0.009). Higher baseline TSH levels were associated with progression from subclinical to overt hypothyroidism (p=0.02) in the multivariate analysis, including age, sex, antithyroid peroxidase antibody, and ultrasonography (US) findings. The analysis using binary TSH data suggested that a TSH level >8 mIU/L was a predictive value for development of overt hypothyroidism (p=0.005). On the other hand, serum TSH levels spontaneously normalized in 38 (53.5%) of the patients with subclinical hypothyroidism. In the multivariate analysis, normalization of TSH levels was associated with lower baseline TSH levels (p=0.004) and normal and homogenous thyroid US findings (p=0.04). Atomic-bomb radiation dose was not associated with subclinical hypothyroidism or its course. Conclusions: Subclinical hypothyroidism was four times more likely to be associated with development of overt hypothyroidism than euthyroid controls in the sample population of Japanese elderly. TSH levels in half of the patients normalized spontaneously when assessed after an average follow-up period of 4.2 years. Baseline TSH level and thyroid US findings are potential predictors of future thyroid function in subclinical hypothyroidism

Diagnostic Criteria of FMD and NID

Background - Diagnostic criteria of flow-mediated vasodilation (FMD), an index of endothelial function, and nitroglycerin-induced vasodilation (NID), an index of vascular smooth muscle function, of the brachial artery have not been established. The purpose of this study was to propose diagnostic criteria of FMD and NID for normal endothelial function and normal vascular smooth muscle function. Methods and Results - We investigated the cutoff values of FMD and NID in subjects with (risk group) and those without cardiovascular risk factors or cardiovascular diseases (no-risk group) in 7277 Japanese subjects (mean age 51.4±10.8 years) from the Flow-Mediated Dilation Japan study and the Flow-Mediated Dilatation Japan Registry study for analysis of the cutoff value of FMD and in 1764 Japanese subjects (62.2±16.1 years) from the registry of Hiroshima University Hospital for analysis of the cutoff value of NID. Receiver-operator characteristic curve analysis of FMD to discriminate subjects in the no-risk group from patients in the risk group showed that the optimal cutoff value of FMD to diagnose subjects in the no-risk group was 7.1%. Receiver-operator characteristic curve analysis of NID to discriminate subjects in the no-risk group from patients in the risk group showed that the optimal cutoff value of NID to diagnose subjects in the no-risk group was 15.6%. Conclusions - We propose that the cutoff value for normal endothelial function assessed by FMD of the brachial artery is 7.1% and that the cutoff value for normal vascular smooth muscle function assessed by NID of the brachial artery is 15.6% in Japanese subjects