Manufacturing carbon storage sintered body using microwave-selective and high-speed heating techniques.

Microwave sintering of fly ash samples with large amounts of unburned carbon and CaCO3 was examined in this study. To this end, CaCO3 was mixed with fly ash sintered body to fix CO2. The decomposition of CaCO3 was observed when the raw material was heated to 1000 °C using microwave irradiation; however, a sintered body containing aragonite was obtained when the raw material was heated to 1000 °C with added water. Further, carbides in the fly ash could be selectively heated by controlling the microwave irradiation. The microwave magnetic field created a temperature gradient of 100 °C in a narrow region of 2.7 µm or less in the sintered body, and it helped suppress the CaCO3 decomposition in the mixture during sintering. By storing water in the gas phase before spreading, CaCO3, which is difficult to sinter using conventional heating, can be sintered without decomposing.

Microwave sintering of fly ash containing unburnt carbon and sodium chloride.

Recently, the application of microwave heating to high-temperature processing has received increased attention. In this study, fly ash containing large amounts of unburnt carbon and sodium chloride was sintered by applying microwaves as part of an investigation of the application of microwave heating to high-temperature processes. Microwave fields were separated by cavities, and pure electrical fields were employed as a heat source. The heating rate and maximum temperature increased with the microwave power, while the fly ash exhibited anomalous heating behavior at 450 °C. In this case, unburnt carbon in the fly ash plays an important role in the microwave absorption properties. At 900-1200 °C, no change was observed in the hardness or composition even when the heating duration was increased. In addition, it was found that the amount of chlorine and carbon in the fly ash decreased as the temperature increased. The chlorine concentration in the sample decreased due to the addition of carbon.

Detoxification mechanism of asbestos materials by microwave treatment.

The detoxification mechanism of asbestos materials was investigated through simulations and experiments. The permittivities of pure CaO and Mg3Si4O12, as quasi-asbestos materials, were measured using the cavity perturbation method. The real and imaginary parts of the relative permittivity (ɛr' and ɛr″) of CaO are functions of temperature, and numerical simulations revealed the thermal distributions in an electromagnetic field with respect to both asbestos shape and material configuration based on permittivity. Optical microscopic observation revealed that the thickness of chrysotile fibers decreased as a result of CaO heating. The heating mechanism of asbestos materials has been determined using CaO phase, and the detoxification mechanism of asbestos materials was discussed based on the heating mechanism.

Relationship between muscle oxygenation kinetics and the rate of decline in peak torque during isokinetic knee extension in acute hypoxia and normoxia.

To investigate whether low FiO2 affects muscle oxygenation and the rate of decline in peak torque (DR) during isokinetic knee extension, subjects performed 50 isokinetic knee extensions at 180 degrees /s and at 0.5 Hz while inhaling low O2 gas (12 %O2; H) or air (N). Muscle oxygenation kinetics was assessed by near-infrared spectroscopy, and whole-body V.O2 and HR were measured. We calculated total-, oxy- and deoxy-hemoglobin/myoglobin concentrations (TotalHb/Mb, OxyHb/Mb, DeoxyHb/Mb), and the slopes of the change in OxyHb/Mb during exercise. SpO2 decreased in H while DR and V.O2 did not differ between the conditions. During exercise, OxyHb/Mb was lower in H than in N, and DeoxyHb/Mb was higher in H than in N. TotalHb/Mb began to increase from the resting level earlier in H. HR was higher during the latter half of the exercise in H. The slopes of the change in OxyHb/Mb were the same in the two conditions. Our results show that low FiO2 decreases SpO2 and muscle oxygenation during maximal isokinetic knee extension. However, low SpO2 and muscle oxygenation did not affect the rates of decline of peak torque. These results suggest that the decline in peak torque occurs for reasons other than O2 availability.

Selective binding of sucralfate to endoscopic mucosal resection-induced gastric ulcer: evaluation of aluminium adherence.

We evaluated the effect of sucralfate in patients with early gastric cancer in endoscopic mucosal resection (EMR)-induced gastric ulcers, and in rats with acetic acid-induced ulcers, by measuring concentrations of aluminium adhering to mucosal lesions. Twenty-two patients who underwent EMR received sucralfate with or without ranitidine and were examined endoscopically after 1 week, 2 weeks and 3 weeks. Gastric juice pH and concentration of aluminium in samples of ulcerated and normal mucosa were measured at various time-points. Good ulcer healing was observed in all patients. Significantly higher concentrations of aluminium were found in ulcerated tissue compared with normal mucosa. This selective binding of sucralfate was even found 12 h after drug administration and was confirmed in acetic acid-induced ulcers in 40 rats. Neutral rather than acid gastric juice was observed up to 12 h after the administration of sucralfate alone. These results suggest that sucralfate with or without ranitidine may contribute to the healing of EMR-induced ulcers by selectively binding to lesions.

Comparison of various submucosal injection solutions for maintaining mucosal elevation during endoscopic mucosal resection.

BACKGROUND AND STUDY AIMS: One of the major complications of endoscopic mucosal resection (EMR) for gastrointestinal tumors is perforation, and the most effective way of preventing perforation is to elevate the lesion sufficiently by endoscopic injection of fluid into the submucosa. MATERIALS AND METHODS: In order to compare the lesion-lifting properties of several different solutions, 1 ml of each of the following solutions was injected into the submucosa of the resected porcine stomach: normal saline, 3.75 % NaCl, 20 % dextrose water, 10 % glycerin with 0.9 % NaCl plus 5 % fructose, and two sodium hyaluronate (SH) solutions. RESULTS: Significantly higher initial elevation was produced by both SH solutions, and it remained higher than that achieved by the other solutions at all times. Hypertonic solutions, especially 10 % glycerin with 0.9 % NaCl plus 5 % fructose, tended to produce and maintain greater mucosal elevation than normal saline, but the difference was not significant. CONCLUSIONS: SH solutions were the most suitable ones for producing and maintaining long-term mucosal elevation, while the superiority of hypertonic solutions over normal saline was not clearly demonstrated.

Different mixtures of sodium hyaluronate and their ability to create submucosal fluid cushions for endoscopic mucosal resection.

BACKGROUND AND STUDY AIMS: Sodium hyaluronate (SH) is a promising submucosal injection solution during endoscopic mucosal resection, but its high cost is an obstacle to more widespread use. The aim of this study was to identify an appropriate low-cost SH solution by varying the molecular weight of SH and mixing various solutions with it. MATERIALS AND METHODS: The viscoelasticity of various SH solutions was first measured. The concentrations of two 1 % SH preparations with different molecular weights (800 kDa and 1900 kDa) were adjusted to 0.5 %, 0.25 %, and 0.125 %, using 0.9 %/3.75 % normal saline (NS), 5 %/20 % dextrose water (DW), and a glycerin solution (Glyceol): 10 % glycerin with 0.9 % normal saline plus 5 % fructose. The ability of these SH solutions to create submucosal fluid cushions (SFCs) was then investigated in the stomachs of two live minipigs. RESULTS: The 0.25 % 1900 kDa SH/NS solution and the 0.125 % 1900 kDa SH/20 % DW solution created a similar viscoelasticity to that of the 0.5 % 800 kDa SH/NS solution. The ability of these solutions to create SFCs was also similar. In addition, the 0.125 % 1900 kDa SH/Glyceol solution created similar SFCs, with a synergistic effect of increased viscoelasticity and the hypertonic nature of glycerin. CONCLUSIONS: A mixture of higher molecular weight sodium hyaluronate with a sugar solution (particularly 20 % dextrose), with or without glycerin, should be regarded as a cost-effective option for creating SFCs instead of the conventional SH solution made with the same amount of a 1 % 800 kDa SH preparation and normal saline.

Left atrial appendage dysfunction in chronic nonvalvular atrial fibrillation is significantly associated with an elevated level of brain natriuretic peptide and a prothrombotic state.

The study tested the hypothesis that left atrial appendage (LAA) dysfunction in nonvalvular atrial fibrillation (NVAF) correlates with a prothrombotic state, and investigated whether the plasma natriuretic peptides are marker of LAA dysfunction in NVAF. Sixty-seven patients underwent transthoracic and transesophageal echocardiography. The left ventricular fractional shortening, left atrial diameter (LAD), LAA flow velocity and the grade of spontaneous echo contrast (SEC) were determined. The plasma concentrations of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), D-dimer, and thrombin-antithrombin III complex (TAT) were measured. The patients were divided into 2 groups according to LAA flow velocity: group I (LAA velocity <20 cm/s) and group II (LAA velocity > or = 20cm/s). The SEC score, D-dimer, TAT, BNP and LAD were significantly increased in group I. Based on simple linear regression analysis, SEC score (r=-0.638), LAD (r=-0.493), D-dimer (r = -0.485), BNP (r = -0.463), TAT (r = -0.455) and age (r = -0.314) were inversely correlated with LAA flow velocity. Multivariate analysis showed that SEC score (p = 0.0014) and plasma BNP level (p=0.0075) were independent negative predictors for LAA flow velocity. In conclusion, LAA dysfunction is associated with a prothrombotic state, and the plasma BNP concentration may serve as a determinant of LAA function in NVAF.

Coexisting primary early gastric plasmacytoma and sarcoidosis with hypercalcaemia.

We report on a 61-year-old woman with coexisting early stage primary gastric plasmacytoma and sarcoidosis with hypercalcaemia. Laboratory data on admission showed hypercalcaemia, with 12.8 mg/dl, parathyroid hormone-related peptide (PTHrP) 1.2 pmol/l, C-PTHrP 69.5 pmol/l, and 1,25-dihydroxyvitamin D3 46.7 pg/ml. Neoplastic plasma cells proliferated in the propria mucosa of the stomach, showed a monoclonal immunoglobulin of cytoplasmic IgA (lambda light chain) and were positive for leucocyte common antigen and epithelial membrane antigen on paraffin section prepared from a stomach biopsy specimen. Russel bodies were present, as were crystals. Abundant sarcoid granulomas were observed in many of the regional lymph nodes around the stomach and in the dermis of a skin nodule. The patient underwent subtotal gastrectomy with administration of antimyeloma chemotherapy. We suggest that the hypercalcaemia in this patient was due to PTHrP production by neoplastic plasma cells.

Changes in transglutaminase activity in carbon tetrachloride-damaged rat liver.

A significant decrease in transglutaminase (TGase) activity was observed in the cytosol and nuclear fractions of carbon tetrachloride-damaged rat liver. The degree of decrease in TGase activity in the cytosol fraction was closely related to the serum transaminase level. Gel filtration studies revealed that TGase activity in 80 kDa fractions significantly decreased, but that in 160 kDa fractions slightly increased after carbon tetrachloride treatment.

[Glucagon-producing carcinoid of the rectum--report of a case].

A 22-year-old male who had been receiving insulin therapy to treat uncontrollable hyperglycemia, was diagnosed to have a carcinoid in the lower rectum. The excised tumor was 1.5 cm in diameter, and showed a yellowish-white cut surface. It did not invade into the proper muscle. Numerous glucagon immunoreactive cells were found. The tumor cells contained many rounded neurosecretory granules. After tumor excision, the patient's hyperglycemia did not return in the absence of insulin administration. We suggest that the tumor may have secreted glucagon which may have acted as an antagonist against insulin in the circulation.