No abstract

Four lower rank coals were oxidized in 0.5 N Na 2 CO 3 aqueous solution, into which atmospheric oxygen gas was bubbled. The reaction was carried out at 20-85 °C, and, after cooling to ambient temperature, the slurry was acidified (pH 1.3) with a 5 N HCl solution. The coals oxidized at 85 °C for 6-24 h were extracted with methanol/tetrahydrofuran mixtures of 25/75 and 50/50 in volume ratio at 30 °C under ultrasonic irradiation. The O 2 oxidation dramatically enhanced the extractability of the coals, and extraction yields reached 80-90 wt % daf. Dimethyl sulfoxide and a mixture of benzene and methanol gave similar extraction yields for each oxidized coal. Pyridine showed lower extraction yields in spite of its higher hydrogen-bond-breaking ability. Extractability was, thus, better correlated with the solubility parameter of solvents than with the heat of hydrogen bond complexation. Diffuse reflectance FTIR analysis revealed that the O 2 oxidation introduced carboxylic, phenolic, and alcoholic hydroxyls into the coals with a decrease in alkyl groups and aryl-alkyl ethers. This structural change was due to the oxidation of aliphatic carbon-hydrogen bonds to peroxides and subsequent dissociation by acid-catalyzed hydrolysis. The O 2 oxidation also converted a portion of the coals to water-soluble acids such as oxalic, formic, acetic, and malonic acids and carbon dioxide. The carbon conversion to CO 2 was negligible for the O 2 oxidation at 20-50 °C and was 5-9 wt % daf for that at 85 °C.

Aim: Suicide is associated not only with primary psychiatric disorders but also with physical disorders. Physicians' education on suicide prevention contributes to reducing suicide. Therefore, medical residents, who contact patients daily and who eventually become primary physicians in each specialty, might be the most appropriate candidates for intervention. In this article, we introduce our newly developed suicide intervention program among medical residents. Methods:We developed a 2-hour suicide intervention program among medical residents, based on the Mental Health First Aid (MHFA), which had originally been developed for the public. The program contains a 1-hour lecture and a 1-hour role-play session. As the first pilot trial, we conducted the program among 44 first-year medical residents at a university hospital and evaluated its effectiveness. Changes in confidence, attitudes and behavior toward suicidal people were evaluated using selfreported questionnaires before, immediately after, and 6 months after the program.Results: Participants' confidence and attitudes significantly improved after the program. The total mean score (standard deviation) of the Suicide Intervention Response Inventory improved from 18.4 (2.0) before the intervention to 19.4 (2.0) immediately after the intervention. However, the effectiveness was limited after 6 months. In the course of 6 months, the participants learned to apply the MHFA principles in their daily clinical practice. Conclusion:Our newly developed brief suicide intervention program demonstrating its effectiveness among medical residents should be modified in order to be more effective in the long term. The next trial with a control group ought to be conducted to evaluate our developed program.

A sequence of hot briquetting and carbonization (HBC) is a promising technology for the production of coke with a high mechanical strength from lignite, but factors affecting the coke strength have not yet been fully understood. The HBC cokes prepared from 12 lignites in this study showed diverse tensile strength (e.g., from 0.2 to 31.2 MPa in the preparation at 200 °C and 112 MPa for hot briquetting and 1000 °C for carbonization), and the coke strengths could not be explained by differences in commonly used structural properties of the parent lignites, such as elemental composition and contents of volatile matter/fixed carbon and ash. In this study, two methods were proposed for correlating the coke strength with the lignite properties, which employed the chemical structure analyzed by solid-state 13C nuclear magnetic resonance or the volumetric shrinkage during carbonization. A stronger coke was obtained from lignite that contained more aliphatic carbons (less aromatic carbons) or shrank more considerably. These characteristics contributed to intensified compaction of lignite in the briquetting and suppression of the formation of large pores, which are a cause of coke fracture. Two empirical equations, predicting the coke strength from the parameters of lignite properties, were established to be criteria for selection of lignite as HBC coke feedstock, although further investigation with more experimental data would be necessary for the validation.

Wereport a 69-year-old womanwith liver cirrhosis due to chronic hepatitis C virus (HCV) infection in whomiat-rogenic arteriovenous fistula (AVF) developed after sig-moidectomy. A soft mass with bruit led to the diagnosis of inferior mesenteric AVF.Most mesenteric AVFcases have portal hypertension, but this patients showednone of the usual symptomsof portal hypertension; however, she had a splenomegaly that became worse after sigmoidectomy. Clinicians should be aware of the possibility ofAVFin patients with a history of abdominal surgery. (Internal Medicine 41: 543-548, 2002)

Summary Background Tenofovir alafenamide (TAF) may be preferable to other nucleos(t)ide analogues (NA) regarding outcomes against chronic hepatitis B virus (HBV) infection. Aims To evaluate the longer term virological/biochemical effectiveness of TAF and the renal safety of sequential therapy to TAF in real‐world settings Methods This multi‐centre, retrospective cohort study included consecutive adult patients who were switched from other NAs to TAF. We assessed the virological and biochemical responses up to 144 weeks. We performed sensitivity analyses for a subgroup with chronic kidney disease (CKD) at baseline. Results We analysed the data of 391 patients with chronic hepatitis B previously treated with entecavir (ETV) (n = 174), tenofovir disoproxil fumarate (TDF) (n = 116) or an NA combination (n = 101) for ≥ 24 months. HBV DNA <10 IU/ml at week 144 was found for 99% of patients, regardless of prior NA regimen or HBV DNA level at baseline. For patients who switched from TDF to TAF, total, low‐density lipoprotein, high‐density lipoprotein cholesterol and triglycerides were significantly increased after the switch. Patients who switched from a nucleotide analogue to TAF had an improved estimated glomerular filtration rate, although the rate of hypophosphataemia (<2.5 mg/dl) remained 9.7% at week 144. The virological and biochemical responses of patients with CKD were similar to the overall results. Conclusions Switching to TAF remained effective and safe for up to 3 years. Given the increasing comorbidities related to ageing, it will be important to carefully follow the change in the lipid levels of patients with a prior TDF‐based regimen.

To develop accurate models for the numerical simulation of coal combustion field, detailed experimental data using laser techniques, which can figure out the basic phenomena in a coal flame, are necessary. In particular, soot is one of the important intermediate substances in a coal flame. This paper is the first paper in the world reporting soot particle size distributions in a coal flame. The spatial distribution of the primary soot particle diameter were measured by the combination of the time-resolved laser induced incandescence (TiRe-LII) method and the thermophoretic sampling (TS) method. The primary soot particle diameter distribution was expressed by the log normal function based on the particle diameter measurement using SEM images obtained from the TS samples. The relative function between the signal decay ratio obtained by TiRe-LII and the primary soot particle diameter was defined based on the log normal function. Using the relative function, the spatial distributions of the primary soot particle diameter with the soot volume fraction were obtained. The results show that the small isolated soot regions instantaneously exist in the entire combustion field. This characteristics is different from spray combustion field. From the ensemble-averaged TiRe-LII images, it was found that the soot volume fraction and the primary soot particle diameter increases with increasing the height above the burner in any radial distance. It was also found that the volumetric ratio of small particles decreases with increasing radial distance at the region close to the burner exit. However, the variation of the soot particle diameter distribution along the radial direction becomes small in the downstream region. This tendency is caused by the turbulent mixing effect. It is expected that the accurate soot formation model will be developed in the near future by using the data reported in this paper.

This work presents experimental observations of strong expanding thermal jets following the application of nanosecond spark discharges. These jets propagate in a toroidal shape perpendicular to the interelectrode axis, with high velocities of up to 30 m/s and over distances of centimeter scale. Their propagation length is much larger than the thermal expansion region produced by the conventional millisecond sparks used in car engine ignition, thus greatly improving the volumetric excitation of gas mixtures. The shape and velocity of the jets is found to be fairly insensitive to the shape of the electrodes. In addition, their spatial extent is found to increase with the number of nanosecond sparks and with the discharge voltage, and to decrease slightly with the pressure between 1 and 7 atm at constant applied voltage. Finally, this thermal jet phenomenon is observed in experiments conducted with many types of gas mixtures, including air, nitrogen, argon, and combustible CH 4 /air mixtures. This makes Nanosecond Repetitively Pulsed (NRP) discharges particularly attractive for aerodynamic flow control or plasma-assisted combustion because of their ability to excite very large volumes of gas.