Polarity Effect and Electromagnetic Radiation of Partial Discharge Accompanying Growth of Electrical Tree

We have investigated the characteristics of radiated electromagnetic (EM) waves from positive and negative partial discharges (PD) in epoxy resin and cross‐linked polyethylene. We found that there is a correlation among the EM level from PD, the positive PD current, and electrical trees. Therefore, the growth of an electrical tree produces a lot of positive PD. We have also investigated the characteristics of the frequency region of EM waves from PD in air, insulating oil, and liquid epoxy in addition to the above insulators. EM waves were detected in the frequency region of 40 MHz to 300 MHz from positive and negative PD in epoxy resin and cross‐linked polyethylene. EM waves were also detected in the frequency region of 40 MHz to 150 MHz from positive and negative PD in air. In the case of insulating oil and liquid epoxy, EM waves were detected in the frequency regions of 40 MHz to 150 MHz from positive PD, and 40 MHz to 250 MHz from negative PD. The frequency region differed depending on the material and the discharge polarity. Our investigation indicates that the cause is differences in electric field strength at the time of PD occurrence.     

Molecular cloning of human Frizzled-6

The Frizzled genes encode receptors for WNTs, secreted glycoproteins implicated in development as well as in carcinogenesis. In this paper, we report molecular cloning of Hfz6, the human homologue of Mfz6. Nucleotide sequence analysis showed that the Hfz6 gene encodes the 706 amino-acid protein with seven transmembrane domains, a cystein-rich domain in the N-terminal extracellular region, two N-linked glycosylation sites, and two cystein residues in the second and third extracellular loops. Hfz6 mRNA 4.4-kb in size was detected in various normal adult and fetal tissues, and a larger amount of Hfz6 mRNA was detected in both fetal lung and fetal kidney. The Hfz6 gene has been mapped to human chromosome 8q22.3-q23.1. In conclusion, we have cloned Hfz6, which encodes a seven-transmembrane receptor with the cystein-rich domain in the N-terminal extracellular region, but without the Ser/Thr-X-Val motif in the C-terminus.     

Recovery of fluorocarbons in Japan as a measure for abating global warming

The objective of this study is to evaluate the potential for recovering fluorocarbons as measures for the abatement of global warming. In this study, we focused on the three different kinds of fluorocarbons: CFCs, HCFCs and HFCs, and targeted refrigerant use because of the availability of relevant data. We first estimated future fluorocarbon emissions from the targeted appliances; we next compared those emissions in the units of CO₂ equivalent to the level of CO₂ emissions in 1990 from a quantitative point of view. As the result of this study, it was found that fluorocarbon emissions in 1999 and 2010 would be equal to approximately 7 and 3% of the level of CO₂ emissions in 1990 respectively. Moreover, if we implement a 100% recovery rate in every recovery route, we can reduce a large amount of emissions which correspond to approximately 2–5% of the level of CO₂ emissions in 1990, even if we take into account the energy-related CO₂ emissions by the transportation and decomposition of fluorocarbons.     

Preparation and antibacterial activity of novel fluoroalkyl end-capped oligomers/silica nanocomposites-encapsulated low molecular biocides

Fluoroalkyl end-capped N-(1,1-dimethyl-3-oxobutyl)acrylamide oligomer [R_F-(DOBAA) _n -R_F] reacted with tetraethoxysilane (TEOS) and silica nanoparticles in the presence of low-molecular weight biocides such as hibitane, hinokitiol, and hinokioil under alkaline conditions to afford R_F-(DOBAA) _n -R_F/silica nanocomposites-encapsulated these biocides in excellent to moderate isolated yields. Fluoroalkyl end-capped N,N-dimethylacrylamide oligomer [R_F-(DMAA) _n -R_F] and acrylic acid oligomer [R_F-(ACA) _n -R_F]/silica nanocomposites-encapsulated hibitane were obtained under similar conditions. Dynamic light scattering measurements showed that the size of these fluorinated nanocomposites-encapsulated biocides thus obtained is nanometer size-controlled. Additionally, these fluorinated nanocomposites were shown to have a good dispersibility and stability in methanol and water. Of particular interest, these fluorinated nanocomposites-encapsulated biocides were found to have a good antibacterial activity against Staphylococcus aureus, and these nanocomposites were applied to the surface modification of traditional organic polymers such as poly(methyl methacrylate).     

Temporal Specificity of Extinction in Autoshaping.

Three experiments investigated the effects of varying the conditioned stimulus (CS) duration between training and extinction. Ring doves (Streptopelia risoria) were autoshaped on a fixed CS-unconditioned stimulus (US) interval and extinguished with CS presentations that were longer, shorter, or the same as the training duration. During a subsequent test session, the training CS duration was reintroduced. Results suggest that the cessation of responding during an extinction session is controlled by generalization of excitation between the training and extinction CSs and by the number of nonreinforced CS presentations. Transfer of extinction to the training CS is controlled by the similarity between the extinction and training CSs. Extinction learning is temporally specific. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Magnetic resonance imaging study on the results of surgery for cervical compression myelopathy

The morphologic changes and signal intensity of the spinal cord on preoperative magnetic resonance images were correlated with postoperative outcomes in 74 patients undergoing decompressive cervical surgery for compressive myelopathy. The transverse area of the spinal cord on T1-weighted images at the level of maximum compression was closely correlated with the severity of myelopathy, duration of disease, and recovery rate as determined by the Japanese Orthopaedic Association score. In patients with ossification of the posterior longitudinal ligament or cervical spondylotic myelopathy, the increased intramedullary T2-weighted magnetic resonance imaging signal at the site of maximal cord compression and duration of disease significantly influenced the rate of recovery. A multiple regression equation was then developed with these three variables to predict surgical outcomes.     

Enhancement by ganglioside GT1b of annexin I phosphorylation in bovine mammary gland in the presence of phosphatidylserine and Ca2+

Ganglioside GT1b and, to a lesser extent, GD3, enhanced phosphorylation of a 36 kDa protein (the substrate of protein kinase C) in the particulate fraction from bovine mammary gland. Sialic acids, asialogangliosides, and GM3 were without effect, and GD1a conversely inhibited phosphorylation of the 36 kDa protein. The enhanced phosphorylation by GT1b required the simultaneous presence of phosphatidylserine (PS) and Ca²⁺. The 36 kDa protein reacted with anti-annexin I in Western blot analysis. Addition of purified annexin I to the reaction mixture containing the particulate fraction increased the extent of phosphorylated 36 kDa protein, and the phosphorylation was further enhanced by GT1b. The enhanced phosphorylation of annexin I by GT1b was also dependent on PS and Ca²⁺. When annexin I was phosphorylated by purified protein kinase C, GT1b inhibited the annexin I phosphorylation. Addition of epidermal growth factor or insulin to the particulate fraction had little effect on the enhancement. These results suggest that an enzyme or enzymes other than protein kinase C, epidermal growth factor receptor kinase, or insulin receptor kinase is responsible for the GT1b- and GD3-enhanced phosphorylation of annexin I in the presence of PS and Ca²⁺.     

Survey of switching techniques in high-speed networks and their performance

One of the most promising approaches for high speed networks for integrated service applications is fast packet switching, or ATM (asynchronous transfer mode). ATM can be characterized by very high speed transmission links and simple, hard-wired protocols within a network. To match the transmission speed of the network links, and to minimize the overhead due to the processing of network protocols, the switching of cells is done in hardware switching fabrics in ATM networks. A number of designs have been proposed for implementing ATM switches. Although many differences exist among the proposals, the vast majority of them are based on self-routeing multistage interconnection networks. This is because of the desirable features of multi-stage interconnection networks such as self-routeing capability and suitability for VLSI implementation. Existing ATM switch architectures can be classified into two major classes: blocking switches, where blockings of cells may occur within a switch when more than one cell contends for the same internal link, and non-blocking switches, where no internal blocking occurs. A large number of techniques have also been proposed to improve the performance of blocking and non-blocking switches. In this paper, we present an extensive survey of the existing proposals for ATM switch architectures, focusing on their performance issues.     

Evaluation of intraductal ultrasonography in the diagnosis of pancreatic cancer

An intraductal ultrasound (IDUS) probe which is inserted via the papilla into the main pancreatic duct (MPD) was evaluated in the diagnosis of 20 patients with pancreatic cancer. The examination was successfully performed with the probe in 17 of the patients (85%). Due to its high frequency (30 MHz) the probe only allowed visualization of the ductal wall and the immediate periductal vicinity (up to about 10 mm). In 15 of the 20 patients the tumors were surgically resected and IDUS scanning was also performed in vitro on the resection specimens, the results being compared to those of histopathological examination. Of these 15 patients, 13 were found to have ductal adenocarcinomas and all but one had been unequivocally diagnosed as having such by ultrasonography (US), computed tomography (CT), endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasonography (EUS). IDUS showed an echorich area (corresponding to cancerous canaliculi on histopathological examination), surrounded by an echopoor area (abundant stroma). This pattern was classified as type I. In two patients with intraductal papillary carcinomas in whom a conclusive diagnosis was not established on US, CT, EUS or ERCP, IDUS showed tumorous tissue with an inhomogeneous echopattern outside (type II) or within (type III) the duct. These results show that IDUS offers valuable diagnostic information complementary to ERCP especially in cases of intraductal papillary tumors. Whether the high resolution imaging of the duct and the paraductal tissue can be used to differentiate between the different forms of pancreatic lesions (inflammation, neoplasms) has to be investigated further.