Psychological distortions of the research process: A summary of psychotherapeutic explorations.

Presents the results of a psychotherapeutic research project concerning psychological blocks to research and creativity. Clients were 10 established researchers and postgraduate students who were offered psychoanalytically based focal-insight therapy. Some of the crucial personal-dynamic problems that hindered the normal development of the knowledge constructing aims of the researcher were anxiety-identity, separation, fear of criticism, competition and envy, research as a means of aggressive outlet, and intellectualization as a mechanism of defense. Illustrative case material is presented. The constructive role of anxiety in research is discussed together with the necessity of viewing research not only as an intellectual but also as an emotional activity. Findings reveal the impact of life situation on research and show a relationship between insight in therapy and the research process. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Distribution of molecular weights and branching of high-density polyethylene

Samples of industrial high-density polyethylenes (Liten Macro, Liten FB 29, and Hostalen GM 9255 F) were divided into fractions by precipitation fractionation. The original samples and their fractions were characterized by light scattering, GPC, and viscometry. For all samples the molecular weight distribution is of logarithmic-normal type. High-density polyethylenes under investigation contain also high-molecular-weight fractions of pronouncedly branched structure, the content of branched molecules being, of course, considerably smaller than that in low-density polyethylenes.     

A study of the compaction process and the properties of tablets made of a new co-processed starch excipient

This article deals with the study of the energetic relationships during compaction and the properties of tablets produced from a co-processed excipient based on starch and called StarCap 1500?. This article compares it with the substance Starch1500?. The study also includes the mixtures of StarCap 1500? and the granulated directly compressible lactose Pharmatose DCL?15. The tablet properties tested included tensile strength and disintegration time, examined in dependence on compression force, and also a 0.4% addition of magnesium stearate. The results show a better compressibility of StarCap 1500 in comparison with Starch 1500 and a lower elastic component of energy. The tablets were stronger and disintegrated more rapidly, but the substance possessed a higher sensitivity to an addition of a lubricant than Starch 1500. Increasing portions of StarCap 1500 in the mixtures with Pharmatose DCL 15 increased the tensile strength of tablets, disintegration period as well as the sensitivity to an addition of a lubricant. From the energetic viewpoint, energy for friction was decreasing, while the energy accumulated by the tablet during compaction and the elastic component of energy were increased.     

制鞋工业中用于抑菌处理的甘油-酸酯

以甘油与不同偶数脂肪酸为原料合成了一系列甘油-酸酯(MAGS):甘油一辛酸酯(MAG C 8:0),甘油一癸酸酯(MAG C10:0),甘油-2-乙基乙酸单酯(MAG 2Eth-C 6:0)和甘油一月桂酸酯(MAG C 12:0),测定其抑菌效果.这些材料以乙醇溶液的形式应用于衬里材料上.酵母菌(白色念菌和近平滑假丝酵母)的实验证明这两种酵母菌对MAG C 8:0和MAG C 10:0敏感.在100～150mg/L的浓度范围内MAG C 8:0和MAG C10:0抑制微生物生长.纤维霉菌特别受到MAG C 8:0(100mg/L)溶液的抑制.当这一浓度的MAG C 8:0溶液应用于被测材料时,黑曲霉、点状毛霉、赭绿青霉具有抵抗性.实验证明,各种MAGS对不同种类可造成霉菌病的真菌微生物的防霉效果不同.     

Impedance measurement of growth of lactic acid bacteria in the presence of nisin and lysozyme

Effect of nisin (0.500 g/l), lysozyme (0.035 g/l) and the mix of nisin (0.500 g/l) and lysozyme (0.035 g/l) against two nisin-producing lactococci strains, three non-nisin-producing lactococci strains and four lactobacilli strains with antimicrobial activity was determined by the impedimetric method. None of the tested lactococci and lactobacilli strains were inhibited by lysozyme at concentration of 0.035 g/l. Only the nisin-producing lactococci strains were resistant to nisin at 0.500 g/l, the other lactococci and lactobacilli were inhibited by nisin at 0.500 g/l intensively. The mix of lysozyme and nisin displayed a comparable effect to the nisin addition against the used lactococci strains and was very variable depending on the strain of tested lactobacilli. The impedimetric method was shown to be convenient for screening the growth abilities of lactococci and lactobacilli in the presence of antimicrobial components.     

Cisplatin electrochemical biosensor

Platinum complexes play an important role in the chemotherapy of various tumour diseases. The aim of this paper was to investigate if a metallothionein (MT) modified hanging mercury drop electrode can be applied as a cisplatin electrochemical biosensor. The modification of the mercury electrode surface by MT and the determination of cisplatin were performed by adsorptive transfer stripping technique and differential pulse voltammetry. The detection limit (3 S/N) of cisplatin ([Pt^II(NH₃)₂Cl₂]⁰) calculated from the decrease of CdT peak was about 2.5 pmol in 5 μl (0.5 μM) at the interaction time of 400 s. Moreover, we tested the influence of human blood serum as a complex biological matrix on the way of determination of cisplatin. On the basis of the obtained results we estimated that we are able to determine tens of picomoles of cisplatin (5 μl drop) in the presence of human blood serum.     

Mechanical properties and microstructure evolution in ultrafine-grained AZ31 alloy processed by severe plastic deformation

Commercial MgAlZn alloy AZ31 was processed by two techniques of severe plastic deformation (SPD)—extrusion followed by equal channel angular pressing (EX-ECAP), and high pressure torsion (HPT). Processing by ECAP was conducted at elevated temperature of 180 °C for 1–12 passes following route B_C. HPT was applied at room temperature, and the specimens of the diameter of 19 mm with different number of turns (N = ¼ ? 15) were prepared. Mechanical properties and grain fragmentation with strain due to EX-ECAP and HPT were investigated by Vickers microhardness measurements and transmission electron microscopy, respectively. Variations in dislocation density were investigated by positron annihilation spectroscopy. Differences in microhardness, grain refinement and dislocation density evolution resulting from principal differences of straining were found in the specimens. EX-ECAP resulted in homogeneous microstructure throughout the specimen's cross section as early as after four passes. On the other hand, laterally inhomogeneous microstructure with gradual reduction of grain sizes from the centre towards the periphery of the disk was observed in specimens after HPT. This microstructure and microhardness inhomogeneities were continuously smeared out and almost homogeneous ultrafine-grained structure was observed in specimen subjected to 15 HPT turns. Variations in mechanical properties and dislocation density evolution were compared in conditions corresponding to the same equivalent strain imposed by both techniques of SPD.     

Antimicrobial Properties of Palladium and Platinum Nanoparticles: A New Tool for Combating Food-Borne Pathogens

Although some metallic nanoparticles (NPs) are commonly used in the food processing plants as nanomaterials for food packaging, or as coatings on the food handling equipment, little is known about antimicrobial properties of palladium (PdNPs) and platinum (PtNPs) nanoparticles and their potential use in the food industry. In this study, common food-borne pathogens Salmonella enterica Infantis, Escherichia coli, Listeria monocytogenes and Staphylococcus aureus were tested. Both NPs reduced viable cells with the log₁₀ CFU reduction of 0.3–2.4 (PdNPs) and 0.8–2.0 (PtNPs), average inhibitory rates of 55.2–99% for PdNPs and of 83.8–99% for PtNPs. However, both NPs seemed to be less effective for biofilm formation and its reduction. The most effective concentrations were evaluated to be 22.25–44.5 mg/L for PdNPs and 50.5–101 mg/L for PtNPs. Furthermore, the interactions of tested NPs with bacterial cell were visualized by transmission electron microscopy (TEM). TEM visualization confirmed that NPs entered bacteria and caused direct damage of the cell walls, which resulted in bacterial disruption. The in vitro cytotoxicity of individual NPs was determined in primary human renal tubular epithelial cells (HRTECs), human keratinocytes (HaCat), human dermal fibroblasts (HDFs), human epithelial kidney cells (HEK 293), and primary human coronary artery endothelial cells (HCAECs). Due to their antimicrobial properties on bacterial cells and no acute cytotoxicity, both types of NPs could potentially fight food-borne pathogens.