Bacteriophages vB_Sen-TO17 and vB_Sen-E22, Newly Isolated Viruses from Chicken Feces,Specific for Several Salmonella enterica Strains

Two newly discovered bacteriophages, isolated from chicken feces and infecting Salmonella enterica strains, are described in this report. These phages have been named vB_Sen-TO17 and vB_Sen-E22, and we present their molecular and functional characterization. Both studied viruses are able to infect several S. enterica strains and develop lytically, but their specific host ranges differ significantly. Electron microscopic analyses of virions have been performed, and full genome sequences were determined and characterized, along with molecular phylogenetic studies. Genomes of vB_Sen-TO17 (ds DNA of 41,658 bp) and vB_Sen-E22 (dsDNA of 108,987 bp) are devoid of homologs of any known or putative gene coding for toxins or any other proteins potentially deleterious for eukaryotic cells. Both phages adsorbed efficiently (>95% adsorbed virions) within 10 min at 42 °C (resembling chicken body temperature) on cells of most tested host strains. Kinetics of lytic development of vB_Sen-TO17 and vB_Sen-E22, determined in one-step growth experiments, indicated that development is complete within 30–40 min at 42 °C, whereas burst sizes vary from 9 to 79 progeny phages per cell for vB_Sen-TO17 and from 18 to 64 for vB_Sen-E22, depending on the host strain. Virions of both phages were relatively stable (from several percent to almost 100% survivability) under various conditions, including acidic and alkaline pH values (from 3 to 12), temperatures from −80 °C to 60 °C, 70% ethanol, chloroform, and 10% DMSO. These characteristics of vB_Sen-TO17 and vB_Sen-E22 indicate that these phages might be considered in further studies on phage therapy, particularly in attempts to eliminate S. enterica from chicken intestine.     

The Mechanical Properties of the Novel Nanocrystalline Refractory Tantalum Alloys

Protection of Metals and Physical Chemistry of Surfaces - The nanocrystalline tantalum alloys were investigated in terms of mechanical properties. The materials were obtained by powder metallurgy...     

Analysis of the effect of structural defects on the fatigue strength of RFSSW joints using C‐scan scanning acoustic microscopy and SEM

Solid‐state refill friction stir spot welding (RFSSW) technology offers significant benefits in the fabrication of aluminium structures in the transport and aerospace industries. In this paper, the joining of 1.6‐mm‐thick Alclad 7075‐T6 aluminium alloy sheets is investigated. High‐cycle fatigue strength tests of single‐lap welded joints were carried out on an Instron E10000 testing machine with a limited number of cycles equal to 2 × 10⁶. The welding of overlap fatigue specimens was conducted using an RPS100 spot welder by Harms & Wende GmbH & Co KG. C‐mode scanning acoustic microscopy (C‐SAM) and scanning electron microscopy (SEM) were utilised to evaluate the joint quality and characterise the microstructure. The paper discusses the effect of the maximum load force and defects (voids, hook, kissing bond, bonding ligament, etc) associated with the material flow in the weld on the failure mechanism. Insufficient plasticisation of sheet material and mixing of the material in the weld area are crucial defects that influence the number of destructive cycles. The weld defects in the joint structure are a source of a decrease in the fatigue life compared with the fatigue life of defect‐free welds. It was also found that RFSSW joint defects can be effectively detected by the nondestructive C‐SAM method.     

Real-time background generation and foreground object segmentation for high-definition colour video stream in FPGA device

The processing of a high-definition video stream in real-time is a challenging task for embedded systems. However, modern FPGA devices have both a high operating frequency and sufficient logic resources to be successfully used in these tasks. In this article, an advanced system that is able to generate and maintain a complex background model for a scene as well as segment the foreground for an HD colour video stream (1,920 × 1,080 @ 60 fps) in real-time is presented. The possible application ranges from video surveillance to machine vision systems. That is, in all cases, when information is needed about which objects are new or moving in the scene. Excellent results are obtained by using the CIE Lab colour space, advanced background representation as well as integrating information about lightness, colour and texture in the segmentation step. Finally, the complete system is implemented in a single high-end FPGA device.     

Design,Synthesis, and Evaluation of ω‐(Isothiocyanato)alkylphosphinates and Phosphine Oxides as Antiproliferative Agents

A series of 21 novel, structurally diverse ω‐(isothiocyanato)alkylphosphinates and phosphine oxides (ITCs) were designed and synthesized in moderate to good yields. The synthesized compounds were evaluated for in vitro antiproliferative activity using LoVo and LoVo/DX cancer cell lines. The biological activity of the synthesized compounds was higher than that of natural isothiocyanates such as benzyl isothiocyanate or sulforaphane. The antiproliferative activity of selected ITCs was also tested on selected cancer cell lines: A549, MESSA and MESSA/DX‐5, HL60 and HL60MX2, BALB/3T3, and 4T1. These compounds were assessed for their mechanism of action as inducers of cell‐cycle arrest and apoptosis. Ethyl (6‐isothiocyanatohexyl)(phenyl)phosphinate ( 71 ) was tested in vivo on the 4T1 cell line and demonstrated moderate antitumor activity, similar to that benzyl isothiocyanate and cyclophosphamide.     

Melt fracture and rheology of linear low density polyethylene ‐ calcium carbonate composites

Rheological behavior and melt fracture of linear low‐density polyethylene (LLDPE) calcium carbonate (CaCO₃) composites were investigated. Two types of commercial inorganic fillers were used, unmodified and modified with stearic acid. Rheological capillary studies were conducted to assess the influence of inorganic filler incorporation as well as chemical treatment on the rheological properties and instability sequence of polyethylene‐based composites. Strong suppression of melt flow instabilities was observed for both types of composites. Mooney analysis was applied to examine the influence of mineral filler addition and stearic acid modification on the wall slip. Moreover, chemical treatment of calcium carbonate allows to obtain better dispersion of the inorganic filler in a polymeric matrix. POLYM. ENG. SCI., 57:998–1004, 2017. © 2016 Society of Plastics Engineers     

Diagnosis of early-stage damage to polymer - glass fibre composites using non-contact measurement of vibration signals

Ensuring reliable operation of the means of transport requires the development of methods for early detection of damage to its components made of composite materials. For diagnostic testing of composite materials during normal operation of the means of transport, the authors propose to use non-contact vibration measurement methods and their subsequent processing and analysis. The paper presents the results of laboratory tests whose aim was to assess the ability to detect early symptoms of damage to composite materials using non-contact vibration measurement methods. The measurements included mechanical curves of the glass composite samples made in a conventional manner and simultaneously their vibrations were measured in a non-contact manner using a laser vibrometer. Continuous wavelet transform was used for processing vibration signals. Calculated time-frequency scale distributions of vibration signals enabled the designation of frequency scale bands in which early, low-energy symptoms of damage to glass composites are observed. The analysis results allow to draw conclusions that the use of non-contact measurements and processing of vibration signals extends the existing range of composites research and enables detection of early, low-energy symptoms of damage to glass fibre reinforced composites.     

Interferometric generation of parametrically shaped polarization pulses

We demonstrate the capabilities of the recently introduced interferometric parallel pulse shaper setup and present a method for fully tailoring the three-dimensional electrical field of femtosecond laser pulses. The possibility of producing parametric polarization pulses with arbitrary orientations and ellipticities in time is demonstrated with a selection of example pulses.