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Surface morphology of monolayers related to solid-state structure for methacrylate comb copolymers having fluorocarbon and hydrocarbon side-chains was investigated by X-ray diffraction (XRD), differential scanning calorimetry (DSC), and atomic force microscopy (AFM). From the XRD profiles, two kinds of short spacing peaks were confirmed at 5.0 and 4.2 A, which assigned the sub-cells for both side-chains. Furthermore, two kinds of endothermic peaks, which corresponded to melting peaks of the both side-chain crystals, appeared in the thermograms. From the AFM observation, it was found that there were hydrogenated domains at a few hundred nm diameter in their monolayers, whereas corresponding acrylate copolymer monolayers form the phase-separated structure at 10–30 nm order scales.

The molecular orientation in monolayer and multilayer films of fluorinated comb copolymers with various monomer ratios can be characterized by in-plane and out-of plane X-ray diffraction (XRD), near-edge X-ray absorption fine structures (NEXAFS) spectroscopy at the C K-edges, and atomic force microscopic observation. And further, the fine structure in the solid state and phase transition behavior of newly synthesized comb copolymers having fluorocarbon and hydrocarbon side-chains were investigated by temperature controlled wide-angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC). From the WAXD profiles, two kinds of short spacing peaks based on the formation of the sub-cell for fluorinated and hydrogenated side-chains were confirmed at 5.0 and 4.1 A, respectively. Furthermore, two kinds of endothermic peaks, which corresponded to melting peaks of both side-chain crystals, appeared in the heating process of the DSC thermograms. From these experimental findings, the phase separation structure having the independently packed immiscible side-chain crystalline formed in the whole polymer crystal. In addition, it was found that these comb polymers formed highly ordered (double) layer structures estimated using WAXD and small-angle X-ray scattering (SAXS). These fluorinated comb copolymers form the monolayer on the water surface and their transferred film with phase separated structure at nanometer size on the solid. There were hydrogenated domains at 10–20 nm diameter scales in these phase separated surface structures of the monolayers. From these experimental results, these copolymer monolayers are expected to be used as in new molecular devices such as nano-lithography based on the surface patterning of polymer nano-materials. Copyright © 2006 John Wiley & Sons, Ltd.

Although conventional bypass grafting is commonly used to treat ischemia in lower extremities, graft failure often occurs. This study retrospectively analyzed the factors that affect graft patency to help establish more effective treatment of obstructive arterial disease of the lower limbs. Kaplan-Meier analysis was used to estimate graft patency in 90 legs of 80 patients who underwent femoropopliteal bypass (28 vein grafts and 62 expanded polytetrafluoroethylene grafts) between 1984 and 2003. Patients were randomly selected for graft materials in sequential surgical treatment order. After initial analysis, several risk factors and postoperative medication regimens were analyzed to ascertain any association with graft failure. The overall mean patency period for femoropopliteal bypass was 10.5 +/- 0.7 years. Graft occlusion occurred in 20 limbs. Neither the materials composing the grafts nor the position of distal anastmosis had any influence on patency maintenance. Graft occlusion rates were significantly greater in patients with either diabetes (p = 0.0049) or rest pain before surgery (p = 0.0011). Postoperative administration of beraprost sodium significantly increased the patency period (p = 0.0082). Diabetes and rest pain before surgery are important factors for late graft failure after femoropopliteal bypass. Our data also suggest that administration of beraprost sodium increases the graft patency period.

Background: The optimal timing of valve surgery is very important. In patients who are severely symptomatic, the marked improvement in symptomatic status observed following successful valve surgery. However, in patients with no or only mild symptoms, the decision is more difficult. The aim of this retrospective study was to determine whether the measurement of plasma brain natriuretic peptides (BNP) levels is useful to decide surgical timing for valve disease. Methods: Fifty-one patients with valve disease underwent single valve surgery (mitral stenosis, MS, 13; mitral regurgitation, MR, 16; aortic stenosis, AS, 14; aortic regurgitation, AR, 8 patients). Blood samples, echocardiographic and cardiac catheterization data were obtained before operation and echocardiographic examination were performed after 1-year of operations. Results: In patients subjected to single heart valve surgery, plasma BNP mean levels were 214.6±48.5 pg/ml. In plasma BNP levels, there was only significant difference between MS and AS group (MS 67.5±9.7 vs. AS 314.3±112.0 pg/ml, P=0.04). There were no relationships between plasma BNP levels and pre-operative cardiac functions. After 1-year of the valve surgery, NYHA functional class was reduced in 36 patients (70.6%) and plasma BNP levels before the surgery significantly correlated with post-operative NYHA functional class. Conclusions: In this retrospective study, patients with high plasma BNP levels significantly impaired the improvement of clinical symptoms after surgery. We have suggested that plasma BNP levels is useful for detecting asymptomatic valvular disease, and is a clinical marker useful in determining the optimal surgical timing.

Objective: To assess the performance of magnetic resonance venography (MRV) for pelvis and deep vein thrombosis in the lower extremities before surgical interventions for varicose veins. Materials and Methods: We enrolled 72 patients who underwent MRV and ultrasonography before stripping for varicose veins of lower extremities. All images of the deep venous systems were evaluated by time-of-flight MRV. Results: Forty-six patients (63.9%) of all were female. Mean age was 65.2 ± 10.2 years (37–81 years). There were forty patients (55.6%) with varicose veins in both legs. Two deep vein thrombosis (2.8%) and three iliac vein thrombosis (4.2%) were diagnosed. All patients without deep vein thrombosis underwent the stripping of saphenous veins, and post-thrombotic change was avoided in all cases. Conclusion: MRV, without contrast medium, is considered clinically useful for the lower extremity venous system.

The European Rock Mechanics Symposium (EUROCK) 2001, Espoo, Finland, 4-7 June, 2001.

International audience; Using ambient seismic noise for imaging subsurface structure dates back to the development of the spatial autocorrelation (SPAC) method in the 1950s. We present a theoretical analysis of the SPAC method for multicomponent recordings of surface waves to determine the complete 3 × 3 matrix of correlations between all pairs of three-component motions, called the correlation matrix. In the case of isotropic incidence, when either Rayleigh or Love waves arrive from all directions with equal power, the only non-zero off-diagonal terms in the matrix are the vertical-radial (ZR) and radial-vertical (RZ) correlations in the presence of Rayleigh waves. Such combinations were not considered in the development of the SPAC method. The method originally addressed the vertical-vertical (ZZ), RR and TT correlations, hence the name spatial autocorrelation. The theoretical expressions we derive for the ZR and RZ correlations offer additional ways to measure Rayleigh wave dispersion within the SPAC framework. Expanding on the results for isotropic incidence, we derive the complete correlation matrix in the case of generally anisotropic incidence. We show that the ZR and RZ correlations have advantageous properties in the presence of an out-of-plane directional wavefield compared to ZZ and RR correlations. We apply the results for mixed-component correlations to a data set from Akutan Volcano, Alaska and find consistent estimates of Rayleigh wave phase velocity from ZR compared to ZZ correlations. This work together with the recently discovered connections between the SPAC method and time-domain correlations of ambient noise provide further insights into the retrieval of surface wave Green's functions from seismic noise.

We experienced a case of chronic traumatic aneurysm of the thoracic arota due to a traffic accident. This paper presents the case with a review of the relevant literature in Japan. A 26-years-old man was seen at the hospital because of an abnormal shadow on a chest X-ray film which was incidentally found 7 years after blunt trauma on the chest at the traffic accident. With contrast enhanced CT and angiography of the chest, the patient diagnosed as having a chronic traumatic aneurysm of the thoracic aorta. The patient was asymptomatic, but was operated on because of possible enlargement of the aneurysm and risk of rupture. Operative procedures included left posterolateral thoracotomy and grafting under partial extracorporeal circulation. Postoperative course was uneventful without particular complication. The patient was discharge from the hospital on the 18th hospital day. Chronic traumatic aneurysm of the thoracic aorata is a rare disease. If the disease is suspected from a blunt trauma on the chest, early diagnosis followed by surgical operation is essential.