Search

This paper presents a new numerical analysis method for cold pilger rolling which leads to compatible improvement of analysis accuracy and shortening calculation time. In pilger rolling, a raw tube is rolled by dozens of “shots”, which is repetitive reciprocating movement of caliber rolls. Previous studies carried out only one shot analysis for shortening calculation time. However, these studies cannot consider an accumulated plastic strain by the dozens of “shots”. The proposed method is composed of two models. In the first preliminary model, the accumulated plastic strain is evaluated based on the strain increment between the two continuous shots. The second main model is given the pre-strain calculated by the preliminary model, and analyses of shots are conducted until tool load becomes stable. This paper clarified the number of shots until stable tool load was obtained in the proposed model. In addition, the proposed model can improve analysis accuracy of the rolling load while shortening calculation time by 60 %, compared with the conventional models of dozen of shots. [ABSTRACT FROM AUTHOR]

Antibiotics have significantly improved our living environments. However, overuse of antibiotics has led to the emergence of multi-drug resistant microorganisms, and the subsequent constant demand for the exploration of novel antibiotics. To this end, antimicrobial peptides (AMPs) have attracted much attention as a novel class of antibiotics. AMPs have strong antimicrobial activity against a wide-range of species, including gram-positive and gram-negative bacteria, fungi, and viruses. In addition, they are also effective against pathogenic organisms that are resistant to conventional drugs. Despite their great potential, the hemolytic activity and a highly broad spectrum of activity of AMPs dictate the need for amendments to develop safe pharmaceuticals. The human body contains commensal microflora as an integral part of complex mucosal surfaces that offers protection against pathogenic organisms. Administration of antibiotics with broad spectra of activity disrupts the indigenous microflora and increases the risks of diarrhea and other fatal infections. Therefore, it is difficult, but vital, to develop treatments capable of rapidly eliminating pathogenic organisms while maintaining the commensal microbiota. As such, novel pharmaceuticals, safe designer AMPs have been heavily researched. In this article, we review recent attempts to spatially and temporally regulate AMPs to enhance the quality-of-life of patients. [ABSTRACT FROM AUTHOR]

Abstract: Saccharomyces cerevisiae cannot utilize cellulose as a carbon source. In nature, cellulose is mainly degraded into glucose by 3 cellulases: endoglucanase II (EG), cellobiohydrolase II (CBH), and β-glucosidase I (BG). A yeast codisplaying these 3 enzymes was constructed by cell surface engineering to directly ferment cellulose into ethanol. The constructed yeast was used to directly ferment newspaper—a carbon source. The newspaper was first pretreated with Trametes sp. Ha1 laccase, and the laccase-treated newspaper was used for investigating the fermentation by the constructed yeast. The results indicated that the laccase-pretreated waste paper could serve as a resource for the production of ethanol by direct fermentation mediated by yeast codisplaying EG, CBH, and BG. [Copyright &y& Elsevier]

The genetic engineering of microorganisms to adsorb metal ions is an attractive method to facilitate the environmental cleanup of metal pollution and to enrich the recovery of metal ions such as rare metal ions. For the recovery of metal ions by microorganisms, cell surface design is an effective strategy for the molecular breeding of bioadsorbents as an alternative to intracellular accumulation. The cell surface display of known metal-binding proteins/peptides and the molecular design of novel metal-binding proteins/peptides have been performed using a cell surface engineering approach. The adsorption of specific metal ions is the important challenge for the practical recovery of metal ions. In this paper, we discuss the recent progress in surface-engineered bioadsorbents for the recovery of metal ions. [Copyright &y& Elsevier]

The levels and distribution of 55 volatile organic compounds (VOCs) were determined by purge and trap GC-MS on water samples from 30 sites within the urban rivers and estuaries of Osaka, a populated industrialized city of Japan. Forty of 55 target VOCs listed in the US EPA Method 524.2 were detected. Dichloromethane (DCM) was found at higher levels at all of the sampling sites. The distribution of dominant VOCs followed four different patterns. First, the most common VOCs (DCM,toluene, trichloroethene and tetrachloroethene) showed concentrationmaxima in the river segments, and the sites of maximum concentrationfluctuated due to irregular large spills and/or loadings. Second, one VOC (cis-1,2dichloroethene) was evenly distributed in particular rivers due to fixed loadings. Both of these patterns were found in the upper and middle reaches. Third, some of VOCs (1,2,3-trichloropropaneand benzene) were specific to a single industrial site and traceableto those sources. Finally, some VOCs showed no concentration maxima along the rivers and entered from multiple sources (chloroform and bromodichloromethane). Diurnal variations of VOCs at the border of the city area, receiving domestic and industrial discharges, provided information to interpret their observed downstream distribution and possible sources. [ABSTRACT FROM AUTHOR]

Abstract: We determined the genetic background that would result in a more optimal display of heterologously expressed β-glucosidase (BGL) on the cell surface of yeast Saccharomyces cerevisiae. Amongst a collection of 28 strains carrying deletions in genes for glycosylphosphatidyl inositol (GPI)-anchored proteins, the Δsed1 and Δtos6 strains had significantly higher BGL-activity whilst maintaining wild type growth. Absence of Sed1p, which might facilitate incorporation of anchored BGL on the cell-surface, could also influence the activity of BGL on the cell surface with the heterologous gene being placed under the control of the SED1 promoter. For the evaluation of its industrial applicability we tested this system in heterologous and homogenous SED1-disruptants of sake yeast, a diploid S. cerevisiae strain, in which either the SED1 ORF or the complete gene including the promoter was deleted by use of the high-efficiency loss of heterozygosity method. Evaluation of disruptants displaying BGL showed that deletion of the SED1 ORF enhanced BGL activity on the cell surface, while additional deletion of the SED1 promoter increased further BGL activity on the cell surface. Compared to heterozygous disruption, homozygous disruption resulted generally in a higher BGL activity. Thus, homozygous deletion of both SED1 gene and promoter resulted in the most efficient display of BGL reaching a 1.6-fold increase of BGL-activity compared to wild type. [Copyright &y& Elsevier]

Convenient detection of Candida albicans in human bodies is essential to treat patients with candidiasis. In this study, we designed a fluorescence-quenched peptide that emits fluorescence after being cleaved by virulent proteases secreted by C. albicans. The designed peptide will enable easy detection of candidiasis in immunocompromised patients. [Copyright &y& Elsevier]

Abstract: Protease-targeted inhibitors have been promising pharmaceuticals. Here, we combined a yeast cell surface display system with a yeast cell chip for the high-throughput screening of protease inhibitors, and succeeded in improving the activity of a protease inhibitor. [ABSTRACT FROM AUTHOR]