Thermal diffusivity in polymers oriented uniaxially in the solid and in the molten state

Measurements of thermal diffusivity were carried out with semicrystalline and amorphous polymers stretched in the solid and in the molten state to different elongations. For semi-crystalline materials two regions in the curves of the diffusivity versus the elongation can be detected. The change occurs at an elongation of 1.4 for the polymers stretched in the solid state and at an elongation of 3 for the polymers stretched in the molten state. For amorphous polystyrene the shape of the curves of thermal diffusivity versus elongation also depends on the mode of stretching. Along with thermal diffusivity measurements, wide angle X-ray scattering investigations were also performed and give explanations for the differences in thermal behavior.     

The Palladium(II) Complex of Aβ4−16 as Suitable Model for Structural Studies of Biorelevant Copper(II) Complexes of N-Truncated Beta-Amyloids

The Aβ4−42 peptide is a major beta-amyloid species in the human brain, forming toxic aggregates related to Alzheimer’s Disease. It also strongly chelates Cu(II) at the N-terminal Phe-Arg-His ATCUN motif, as demonstrated in Aβ4−16 and Aβ4−9 model peptides. The resulting complex resists ROS generation and exchange processes and may help protect synapses from copper-related oxidative damage. Structural characterization of Cu(II)Aβ4−x complexes by NMR would help elucidate their biological function, but is precluded by Cu(II) paramagneticism. Instead we used an isostructural diamagnetic Pd(II)-Aβ4−16 complex as a model. To avoid a kinetic trapping of Pd(II) in an inappropriate transient structure, we designed an appropriate pH-dependent synthetic procedure for ATCUN Pd(II)Aβ4−16, controlled by CD, fluorescence and ESI-MS. Its assignments and structure at pH 6.5 were obtained by TOCSY, NOESY, ROESY, 1H-13C HSQC and 1H-15N HSQC NMR experiments, for natural abundance 13C and 15N isotopes, aided by corresponding experiments for Pd(II)-Phe-Arg-His. The square-planar Pd(II)-ATCUN coordination was confirmed, with the rest of the peptide mostly unstructured. The diffusion rates of Aβ4−16, Pd(II)-Aβ4−16 and their mixture determined using PGSE-NMR experiment suggested that the Pd(II) complex forms a supramolecular assembly with the apopeptide. These results confirm that Pd(II) substitution enables NMR studies of structural aspects of Cu(II)-Aβ complexes.     

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.     

Authenticity Assessment of the “Onisiówka” <Emphasis Type="Italic">Nalewka</Emphasis> Liqueurs Using Two-Dimensional Gas Chromatography and Sensory Evaluation

The “Onisiówka” nalewka liqueur is a regional Polish alcoholic beverage, which is inscribed on the list of regional and traditional products of the Ministry of Agriculture and Rural Development in Poland. It is produced from multiflower honey, black elderberry flower syrup, and spirit. Due to fact that the “Onisiówka” nalewka liqueur has never been investigated, these studies are the foundation for further work on this regional alcoholic beverage. The main aim of this work is the authenticity assessment of the “Onisiówka” nalewka liqueurs by means of qualitative characteristics of volatile fraction and sensory evaluation. Tentative identification has been performed using two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC-TOFMS). Application of GC×GC-TOFMS allowed for detection of around 350 compounds present in the volatile fraction of the “Onisiówka” from which 102 compounds were tentatively identified. PCA results showed that the first two principal components constitute 96.98% of total variance. Statistical analysis was used to visualize relations between tentatively identified compounds; therefore, it has been demonstrated that 23 chemical compounds may have significant influence on the overall flavor and taste of the “Onisiówka”. These substances belong to four chemical classes, in which the greatest number is represented by esters (13), aldehydes (6), alcohols (3), and one terpene compound. According to the sensory evaluation, the Onisiówka is characterized by sweet, honey, fruity, flowery, bitter, and spirituous flavor and taste.     

Effect of temperature and initial dibutyl sulfide concentration in chloroform on its oxidation rate by ozone

A scheme of dibutyl sulfide (DBS) oxidation with ozone and generation of transitional products was determined in this study. The main identified intermediate product was dibutyl sulfoxide (DBSO), and the main end product of DBS oxidation was dibutyl sulfone (DBSO2). It was determined that for three temperatures: 0, 10 and 20 degrees C there was certain initial DBS concentration for which half-times observed in experimental conditions were equal and independent from temperature. Generation of phosgene and water as by-products was confirmed for the reaction of DBS with ozone in chloroform. Results of the described study allowed to present generalized mechanism of sulfide oxidation with ozone.     

Zn(1-x)MnxTe diluted magnetic semiconductor nanowires grown by molecular beam epitaxy

It is shown that the growth of II-VI diluted magnetic semiconductor nanowires is possible by the catalytically enhanced molecular beam epitaxy (MBE). Zn(1-x)MnxTe NWs with manganese content up to x=0.60 were produced by this method. X-ray diffraction, Raman spectroscopy, and temperature dependent photoluminescence measurements confirm the incorporation of Mn(2+) ions in the cation substitutional sites of the ZnTe matrix of the NWs.     

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.     

1-V Inverting and Non-inverting Loser-Take-All Circuit and Its Applications

A new solution for a non-conventional loser-take-all (LTA) circuit is proposed in the paper. The circuit possesses several inverting and non-inverting input terminals and an additional current output, which increases its versatility and allows simplifying its possible applications. In order to show its usefulness and versatility, several new applications of the proposed LTA have also been developed, including a simple digital-to-analog converter, an n-bit programmable adder/summer, a chopper modulator and a precision rectifier. The LTA has been designed and fabricated with a 0.35 \(\upmu \hbox {m}\) CMOS I3T25 AMIS process, exploiting the recently proposed bulk-driven quasi-floating-gate technique. The LTA circuit operates from 1 V supply and dissipates 74 \(\upmu \hbox {W}\) of power. The simulations performed in Cadence environment and the measurements of a real chip confirm the attractive features of the proposed LTA.