Behavior of Cu nanoparticles ink under reductive calcination for fabrication of Cu conductive film

Cu nanoparticle ink was prepared from Cu nanoparticles that were coated with a gelatin layer at an average diameter of 46 nm. The Cu nanoparticle ink was applied on the polyimide substrate. Conductive films were fabricated using the Cu nanoparticle ink with a two-step annealing process consisting of oxidative pre-heating at 200 °C under 10 ppm O₂-N₂ mixed gas flow and reductive calcination at 250 °C under 3 vol.% H₂-N₂ mixed gas flow showed a low resistivity of 5 μΩ cm. The hydrolysis of the remaining gelatin layer by H₂O vapor, which was formed during the reduction of the Cu oxide by 3 vol.% H₂-N₂ mixed gas, was suggested. The results suggest the possibility of the removal of the gelatin layer without oxidative pre-heating and simultaneous sintering of Cu nanoparticles in reductive calcination.     

Development of green composite consists of woodchips, bamboo fibers and biodegradable adhesive

From the viewpoint of the effective utilization of waste wood, the green composite which is produced by solidifying woodchips has been developed [Miki M, Takakura N, Kanayama K, Yamaguchi K, Iizuka T. Effects of forming conditions on compaction characteristics of wood powders. Trans Jpn Soc Mech Eng C 2003;69(678):502–8 [in Japanese]; Miki M, Takakura N, Kanayama K, Yamaguchi K, Iizuka T. Effects of forming conditions on flow characteristics of wood powders. Trans Jpn Soc Mech Eng C 2003;69(679):766–72 [in Japanese]; Miki M, Takakura N, Iizuka T, Yamaguchi K, Kanayama K. Possibility and problems in injection moulding of wood powders. Trans Jpn Soc Mech Eng C 2004;70(698):2966–72 [in Japanese]]. Since the composite was solidified by the compressive load without the binder, it did not have the high strength and was very brittle, and it had no water resistance [Kinoshita H, Kaizu K, Koga K, Tokunaga H, Ikeda K. In: Proceeding of the Japan Society of Mechanical Engineers M& M2007; 2007. CD [in Japanese]]. In this study, to improve these defects, it was proposed that a biodegradable resin as an adhesive and bamboo fibers as reinforced fibers were applied to the woodchip composite. By using woodchips with two kinds of the particle size, bamboo fibers with three kinds of the length and the biodegradable adhesive, several kinds of specimens changed mixing ratio of those materials were produced by compression molding at the appropriate temperature. By examining the bending strength and impact strength of the composites, it was found that the high bending strength was obtained in the case where woodchips with the small particle size and long bamboo fibers were used, and the high impact strength was obtained in the case where woodchips with the large particle size and long bamboo fibers were used.     

Production of aluminum-matrix carbon nanotube composite using high pressure torsion

In this study, an Al-based composite containing carbon nanotubes (CNTs) was fabricated using a process of severe plastic deformation through high pressure torsion (HPT). Neither heating nor sintering was required with the HPT process so that an in situ consolidation was successfully achieved at ambient temperature with 98% of the theoretical density. A significant increase in hardness was recorded through straining by the HPT process. When the composite was pulled in tension, the tensile strength of more than 200 MPa was attained with reasonable ductility. Transmission electron microscopy showed that the grain size was reduced to 100 nm and this was much smaller than the grain size without CNTs and the grain size reported on a bulk sample. High resolution electron microscopy revealed that CNTs were present at grain boundaries. It was considered that the significant reduction in grain size is attributed to the presence of CNTs hindering the dislocation absorption and annihilation at grain boundaries.     

Epstein-Barr virus-positive multiple early gastric cancers and dysplastic lesions: a case report

Epstein-Barr virus (EBV) has been implicated as a causal virus of gastric cancer with episomal monoclonality, elevated antibodies and a unique morphologic expression in the early intramucosal stage, but the infection mechanisms have not been demonstrated. EBV has been shown only in the cancerous lesions by the highly sensitive EBV-encoded small RNA in situ hybridization (EBER-ISH) method, not in the dysplastic mucosa adjacent to the cancer. A case is presented of multiple EBV-positive gastric cancer and dysplastic epithelium observed in a 52-year-old man. Serial cut sections of the gastrectomy specimen showed four small cancerous lesions, three of which were EBER-positive, and three EBER-positive, minute, non-cancerous dysplastic lesions. The three cancerous lesions were intramucosal cancer, with one having minimal submucosal invasion forming a lymphoepithelioma-like histology. All of these EBER-positive cancerous and dysplastic lesions showed intense CD8 T-lymphocytic infiltration. There was no such findings in the EBV-negative cancerous lesion. It was concluded that EBV infection may occur in the epithelial cells of atrophic gastric mucosa, and progress to cancer with monoclonal expansion through the EBV-positive dysplastic change. Cytotoxic T-lymphocytic reactions can occur even in the dysplastic lesions. Multifocal EBV infection in the gastric mucosa may occur and, if necessary, total gastrectomy is recommended in such a case.     

Plasma concentrations of antipsychotic drugs in psychiatric inpatients

We surveyed a random sample (n = 75) of doctors and dentists at University College Hospital, Ibadan, Nigeria. They were offered anonymous testing for hepatitis B surface antigen (HBsAg), hepatitis Be antigen (HBeAG), antibodies to hepatitis B core antigen (anti-HBc) and to hepatitis C virus (anti-HCV), by enzyme immunoassay. The results suggest a high prevalence of hepatitis B virus (HBV) with a high potential of transmissibility, as well as a high prevalence of HCV infection. The majority of the doctors and dentists use universal precaution for protection against viral hepatitis on < 50% of the occasions when they carry out procedures on their patients. Infection with HBV was associated with type of specialty (surgeons, dentists) and lack of HBV vaccination (p < 0.05). After logistic regression, these factors were independently associated with HBV infection (p < 0.05). Sixty (80%) had not received prior HBV vaccination. Unvaccinated personnel were more likely to be surgeons, dentists, < 37 years of age, and have fewer years of professional activity (p < 0.05). After logistic regression, only fewer years of professional activity remained independently associated with lack of vaccination (p < 0.05). To reduce the occupational exposure of HBV, universal precautions must be rigorously adhered to when the doctors and dentists carry out procedures on their patients, and all health-care workers should be vaccinated with HBV vaccine and the HCV vaccine, when it becomes available.     

YM-32890 A and B, new types of macrolide antibiotics produced by Cytophaga sp

Two new types of macrolide antibiotics, YM-32890 A and B, have been isolated from the fermentation broth of cytophaga sp. YL-02905S. In this paper, the taxonomy of the producing strain, fermentation, isolation, structure elucidation, and biological activity of the antibiotics are reported. YM-32890 A inhibits the growth of staphylococci including a macrolide-resistant strain, but shows no antimicrobial activity against other Gram-positive, Gram-negative bacteria and yeast.     

Six patients in whom exacerbation of asthma was complicated by mediastinal emphysema

We encountered 6 patients with bronchial asthma complicated by mediastinal emphysema. Their average age was 21 years. All were atopic and had histories of asthma in childhood. In 5 of the 6, mediastinal emphysema developed when the patients had upper respiratory infections. In 3, the mediastinal emphysema worsened. After insertion of subcutaneous drains to decrease intramediastinal pressure, the conditions of those 3 patients improved remarkably. The conditions of the other 3 improved after medication only. During the period of this study, 1.24% of all patients treated at Hiroshima Asa Citizen's Hospital for exacerbations of asthma had mediastinal emphysema.     

HLA-A26 subtype A pockets accommodate acidic N-termini of ligands

BACKGROUND: Fiberoptic flexible sigmoidoscopy (FFS) is routinely requested preoperatively as part of evaluation of pelvic masses to exclude colonic involvement by the tumor or concurrent colonic neoplasm. The aim of our study was to evaluate the utility of preoperative FFS in patients with suspected gynecologic malignancy. METHODS: FFS, performed using a 60 cm sigmoidoscope, evaluated (1) presence of bowel involvement by the tumor, (2) extrinsic compression by the tumor, and (3) presence of colonic neoplasms. FFS findings were correlated with surgical findings. RESULTS: A total of 107 women underwent preoperative FFS and subsequent surgery. Eleven patients (11%) had lower gastrointestinal symptoms. At surgery, 63% of pelvic tumors were malignant and 37% were benign. The most common abnormality at FFS was colonic polyps in 23 patients (21%). Colonic adenomas were found in 11 patients (10%). Extrinsic compression by the tumor without mucosal abnormalities was seen in 15 patients (14%). The most common intraoperative finding was tumor adhering to the bowel in 18 patients requiring dissection, but only 1 patient required bowel resection. Eight of these 18 patients had preoperative lower gastrointestinal symptoms. All 15 patients with extrinsic compression at FFS had tumor adhering to the bowel. CONCLUSIONS: Pelvic masses cause extrinsic compression at FFS in 14% of patients. This is suggestive of tumor adherent to the bowel at surgery. However, bowel resection is rarely required because of tumor involvement. Most patients with bowel adherence by tumor have lower gastrointestinal symptoms. Colonic adenomas are found in one tenth of patients, mostly in patients older than 50 years of age. Preoperative FFS does not change the surgical management of pelvic tumors. Screening FFS is indicated in all patients with pelvic tumors over age 50, as in persons with average risk, but is otherwise unnecessary in evaluation of pelvic masses.