A case of anastomotic aneurysm-enteric fistula

Reimplantation failure of avulsed anterior teeth in an adolescent patient requires removal of the attempted-reimplanted teeth and consideration of several restorative options. These options may include a removable partial denture, as well as a transitional bridge or permanent fixed prosthesis. In all cases, the potential effects of the adolescent's expected amount and directions of maxillary and mandibular growth must be considered. A case is presented examining how maxillary growth may affect the restorative treatment options for avulsed anterior teeth replacement for an adolescent boy. Unfortunately, the patient and family were unable to complete treatment due to financial considerations. Consequently, the case presented here is submitted as a treatment planning exercise.     

Flexible pulse waveform generation using silica-waveguide-based spectrum synthesis circuit

Pulse waveform shaping with a silica-waveguide-based circuit employing an arrayed-waveguide grating pair and an array of amplitude and phase controllers is demonstrated. The frequency components of a modelocked laser have been flexibly synthesised to produce 40 GHz square pulses with various widths.     

Two-channel-based Noise Reduction in a Complex Spectrum Plane for Hands-free Communication System

For hands-free communication system, this paper describes a noise reduction method using a two-channel microphone. Recently, the Complex Spectrum Circle Centroid (CSCC) method has been proposed. This method utilizes geometric information and estimates the spectrum of the target signal. The method is advantageous in that no adjustment of the array-processing parameters to the environment is necessary before its operation and it is effective with non-stationary noise. However, the original CSCC method requires at least three microphones to estimate the spectrum of the target signal (center of circle). In this paper, we propose a method which estimates the spectrum of the target signal using only two microphones. In experimental results, the proposed method achieves the performance as good as the original CSCC method and can restore the target signal almost completely in a simulated noisy environment.     

Molecular cloning of cDNA for nonhepatic mitochondrial arginase (arginase II) and comparison of its induction with nitric oxide synthase in a murine macrophage-like cell line

Arginase exists in two isoforms. Liver-type arginase (arginase I) is expressed almost exclusively in the liver and catalyzes the last step of urea synthesis, whereas the nonhepatic type (arginase II) is expressed in extrahepatic tissues. Arginase II has been proposed to play a role in down-regulation of nitric oxide synthesis. A cDNA for human arginase II was isolated. A polypeptide of 354 amino acid residues including the putative NH2-terminal presequence for mitochondrial import was predicted. It was 59% identical with arginase I. The arginase II precursor synthesized in vitro was imported into isolated mitochondria and proteolytically processed. mRNA for human arginase II was present in the kidney and other tissues, but was not detected in the liver. Arginase II mRNA was coinduced with nitric oxide synthase mRNA in murine macrophage-like RAW 264.7 cells by lipopolysaccharide. This induction was enhanced by dexamethasone and dibutyryl cAMP, and was prevented by interferon-gamma. Possible roles of arginase II in NO synthesis are discussed.     

Effect of different magnitudes of tension force on prostaglandin E2 production by human periodontal ligament cells

Periodontal ligament (PDL) cells are known to produce prostaglandin E2 (PGE2) in response to mechanical stress. However, the rate of PGE2 production from PDL cells in response to different magnitudes of tension forces has not been examined. This study, therefore, was undertaken to determine the effect of different magnitudes of tension forces on PGE2 production and inositol trisphosphate (IP3) levels in PDL cells in vitro. Human PDL cells were cultured on flexible-bottomed plates and placed on a Flexercell strain unit. Cells were flexed at six cycles (5-s strain, 5-s relaxation) at six steps of tension force (9, 12, 15, 18, 21, 24% increase in surface area) for 5 days. PGE2 production and IP3 levels were determined by radioimmunoassay. There was a 6- and 25-fold increase in the rate of PGE2 production by cells exposed to low (9%) and high (24%) tension forces, respectively, and these increases were tension force-dependent. Tension force also induced increases in the intracellular levels of IP3 that did not seem to be directly related to the production of PGE2. The different rates of PGE2 production by PDL cells in response to different magnitudes of mechanical stress may be of importance in PDL and alveolar bone metabolism.     

Unrepeatered transmission of an OTDM 40 Gbit/s signal over 110 kmusing a dispersion-adjustable PLC delay equaliser

Using a dispersion-adjustable PLC delay equaliser, unrepeatered 110 km transmission of a 40 Gbit/s PRBS signal over both positive and negative dispersion fibre has been successfully demonstrated for the first time     

Immunohistochemical localization of arginase II and other enzymes of arginine metabolism in rat kidney and liver

Arginine is a precursor for the synthesis of urea, polyamines, creatine phosphate, nitric oxide and proteins. It is synthesized from ornithine by argininosuccinate synthetase and argininosuccinate lyase and is degraded by arginase, which consists of a liver-type (arginase I) and a non-hepatic type (arginase II). Recently, cDNAs for human and rat arginase II have been isolated. In this study, immunocytochemical analysis showed that human arginase II expressed in COS-7 cells was localized in the mitochondria. Arginase II mRNA was abundant in the rat small intestine and kidney. In the kidney, argininosuccinate synthetase and lyase were immunostained in the cortex, intensely in proximal tubules and much less intensely in distal tubules. In contrast, arginase II was stained intensely in the outer stripes of the outer medulla, presumably in the proximal straight tubules, and in a subpopulation of the proximal tubules in the cortex. Immunostaining of serial sections of the kidney showed that argininosuccinate synthetase and arginase II were colocalized in a subpopulation of proximal tubules in the cortex, whereas only the synthetase, but not arginase II, was present in another subpopulation of proximal tubules. In the liver, all the enzymes of the urea cycle, i.e. carbamylphosphate synthetase I, ornithine transcarbamylase, argininosuccinate synthetase and lyase and arginase I, showed similar zonation patterns with staining more intense in periportal hepatocytes than in pericentral hepatocytes, although zonation of ornithine transcarbamylase was much less prominent. The implications of these results are discussed.     

Polymeric Reaction of Methacrylic Polymer: Monomer System Irradiated by Low-Energy Electron Beam

The low-energy electron beam (EB) curing process has been proposed as a new manufacturing method for papers, foils, and films which may substitute for the heating and ultraviolet (UV) process. Recently, the process was applied to the curing of magnetic media, pressure-sensitive adhesives, and high-gloss printing, because of its economic benefits and the improved mechanical property of the coatings. One advantage characteristic of the EB process is high-speed polymerization of 100% solids without heating. The EB process has been industrialized in manufacturing processes involving high-gloss printing and coating with thin films, which might deteriorate in processes involving heating.     

A biomimetic underwater microrobot with multifunctional locomotion

Underwater microrobots are in urgent demand for applications such as pollution detection and video mapping in limited space. Compact structure, multi-functionality, and flexibility are normally considered incompatible characteristics for underwater microrobots. Nevertheless, to accomplish our objectives, we designed a novel inchworm-inspired biomimetic locomotion prototype with ionic polymer metal composite (IPMC) actuators, and conducted experiments to evaluate its crawling speed on a flat underwater surface. Based on this type of biomimetic locomotion, we introduced a new type of underwater microrobot, using ten IPMC actuators as legs or fingers to implement walking, rotating, floating, and grasping motions. We analysed the walking mechanism of the microrobot and calculated its theoretical walking speed. We then constructed a prototype of the microrobot, and carried out a series of experiments to evaluate its walking and floating speeds. Diving/surfacing experiments were also performed by electrolysing the water around the surfaces of the actuators. The microrobot used six of its actuators to grasp small objects while walking or floating. To implement closed-loop control, we employed three proximity sensors on the microrobot to detect an object or avoid an obstacle while walking.