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Paratuberculosis (PTB) is a chronic contagious granulomatous enteritis of wild and domestic ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP). PTB causes considerable economic losses to the dairy industry through decreased milk production and premature culling. PTB-affected cattle undergo a subclinical stage without clinical signs and initiate fecal shedding of MAP into the environment. Current diagnostic tools have low sensitivity for the detection of subclinical PTB infection. Therefore, alternative diagnostic tools are required to improve the diagnostic sensitivity of subclinical PTB infection. In this study, we performed ELISA for three previously identified host biomarkers (fetuin, alpha-1-acid glycoprotein, and apolipoprotein) and analyzed their diagnostic performance with conventional PTB diagnostic methods. We observed that serum fetuin levels were significantly lowered in the subclinical shedder and clinical shedder groups than in the healthy control group, indicating its potential utility as a diagnostic biomarker for bovine PTB. Also, fetuin showed an excellent discriminatory power with an AUC = 0.949, a sensitivity of 92.6%, and a specificity of 94.4% for the detection of subclinical MAP infection. In conclusion, our results demonstrated that fetuin could be used as a diagnostic biomarker for enhancing the diagnostic sensitivity for the detection of subclinical MAP infections that are difficult to detect based on current diagnostic methods.

The increasing emergence of drug-resistant bacteria creates a requirement for new antibiotics and various types of antibiotic materials such as proteins, peptides, polymers, and chemical compounds. Among these, antimicrobial peptides (AMPs) are considered to be promising antibiotic candidates for clinical treatments. In this study, we have designed a novel series of peptides with repeated sequences of minimum membrane-active motif, ‘XWZX’ basic sequence (X: lysine or arginine, Z: leucine, tyrosine, valine, or glycine), and an α-helical secondary structure. Some peptides displayed a potent antibacterial activity via membranolytic action and high therapeutic index (toxic dose/minimum inhibitory concentration) in vitro. Furthermore, in vivo experiments using bacterial ear-skin infection models verified that these peptides have the potential to be powerful and safe antibiotics. The present study provides a lead sequence for designing peptide antibiotics against bacterial membranes and information for cell-selectivity of hydrophobic amino acids with aromatic side chains such as Trp and Tyr.

The nucleotide sequence of a 3955-bp Helicobacter pylori plasmid, pHP51 was determined, and two open reading frames, ORF1 and ORF2, were identified. The deduced amino acid sequence of ORF1 was highly conserved (87-89%) among plasmid replication initiation proteins, RepBs. The function of ORF2 was not assigned because it lacked known functional domains or sequence similarity with other known proteins, although it had a HPFXXGNG motif that was also found in the cAMP-induced filamentation (fic) gene. Three kinds of repeats were present on the plasmid outside of the ORFs, including the R1 and R2 repeats that are common in H. pylori plasmids. One 100-bp sequence detected in the noncoding region of pHP51 was highly similar to the genomic sequence of H. pylori 26695.

In this study, the deformation behavior of aluminium during equal channel angular pressing (ECAP) was calculated on the basis of a dislocation density-based model. The behavior of the material under ECAP, including the dislocation density and cell size evolution as well as texture development, was simulated using the finite element method (FEM). The simulated stress, strain and cell size were compared with the experimental data, which were obtained by ECAP for several passes in a modified Route C regime. Good agreement between simulation results and experimental data, including strain distribution, dislocation density and cell size evolution, strain hardening and texture development was obtained. As concerns the general trends, the stress was found to increase rapidly in the first ECAP pass, the strain-hardening rate then dropping from the second pass on. Calculations showed a non-uniform strain distribution evolving in the course of ECAP. The simulated cell size is also in good agreement with the experiment, particularly with the observed rapid decrease of the cell size during the first pass slowing down from the second pass onwards. Larger cells were found to form in the upper and the lower parts of the workpiece where the strain is smaller than in the middle part. Due to the accumulation of strain throughout the workpiece and an overall trend to saturation of the cell size, a decrease of the difference in cell size with the number of passes was predicted.

A yield criterion of sheets with slot-type holes under biaxial loading has been proposed in terms of apparent stresses. The yield criterion was confirmed by finite-element analysis results. In order to analyse stretching of a perforated sheet for slot-type shadow mask by finite-element method, a yield function which can incorporate the apparent yield stress and the apparent plastic contraction ratio has been obtained. The agreement between the measured and calculated results of stretch forming of the perforated sheet was satisfactory.

A yield criterion of sheets with a uniform triangular pattern of round holes under biaxial loading has been proposed in terms of apparent stresses. The yield criterion was confirmed by finite element analysis results in the whole range of ligament efficiency of the perforated sheet. In order to analyse stretching of a perforated sheet for dot-type shadow mask by the finite element method, a yield function which can incorporate the apparent yield stress and the apparent plastic contraction ratio has been obtained. The agreement between the measured and calculated results of stretch forming of the perforated sheet was satisfactory.

Two-dimensional (2D) and three-dimensional (3D) finite-element methods (FEM) have been used to analyse the deformation behaviour of a perforated sheet during uniaxial tension. The 2D results analysed under plane stress and plane strain have been compared with the results of 3D analysis. As the thickness and the diameter of holes increase, the deformation behaviour at the yield point becomes closer to plane strain. A shadow mask was used for the tensile test of the perforated sheet, the shadow mask containing holes the size of which varied across the thickness. Because the apparent plastic contraction ratio of the perforated sheets was dependent on hole size, the tensile specimens of the shadow mask suffered bending when subjected to unaxial tension. The calculated radii of curvature of the bent specimens as a function of strain were found to be in good agreement with measured data.

The proper design and manufacture of tube sheets in heat exchangers and shadow masks in color picture tubes require the characterization of the deformation behavior of perforated sheets containing a large number of holes. The limit or failure strains in sheet metal forming are best represented by a forming limit curve (FLC) which indicates the onset of necking over all possible combinations of strains in the plane. A number of theoretical treatments have been developed to predict the FLC of continuum materials. However, there are few reports on the experimental and theoretical studies on FLC for a perforated sheet. The purpose of this paper is to propose a model which can explain the FLC of a perforated sheet for dot-type shadow mask.