Amphiphilic four-helix bundle peptides designed for light-induced electron transfer across a soft interface

A family of four-helix bundle peptides were designed to be amphiphilic, possessing distinct hydrophilic and hydrophobic domains along the length of the bundle's exterior. This facilitates their vectorial insertion across a soft interface between polar and nonpolar media. Their design also now provides for selective incorporation of electron donor and acceptor cofactors within each domain. This allows translation of the designed intramolecular electron transfer along the bundle axis into a macroscopic charge separation across the interface.     

Thermal Characterization of Metakaolin-Based Geopolymer

Thermal characterization of geopolymer powder was investigated at room and elevated temperatures. The physical, chemical and mass change with respect to various temperatures have been studied. The physical properties such as density, porosity, and particle size were analyzed in geopolymer powder. The chemical and phase compositions were determined by x-ray fluorescence. The surface images of solid blocks of geopolymer were examined at room and elevated temperatures using scanning electron microscopy. Thermal expansion, shrinkage, and mass loss behavior towards the elevated temperatures were investigated by differential scanning calorimetry (DSC). The endothermic peak arising in the DSC curve is due to evaporation of water, chemical, gases and weight loss.     

Characterization of a 82Rb generator for positron emission tomography

Characteristics of the developed ⁸²Rb medical generator intended for the production of Rubidium Chloride, ⁸²Rb from Generator radiopharmaceutical for positron emission tomography (PET) are examined. The results of laboratory tests and clinical trials are presented. The influence of thermal sterilization on the ionexchange characteristics of the sorbent based on hydrous tin(IV) oxide is studied. The possibility of radiation “self-sterilization” of the generator column and of the maintenance of aseptic conditions in it throughout the generator operation life is assessed. In the course of operation of one generator, it is possible to obtain up to 19 L of a sterile and apyrogenic solution of the radiopharmaceutical with permissible content of radioactive and stable impurities. The efficiency of the ⁸²Rb elution from the sorbent at different eluent flow rates is determined. The efficiency of using the generator in PET investigations in cardiology and oncology is demonstrated.     

Injury-Induced Innate Immune Response During Segment Regeneration of the Earthworm,Eisenia andrei

Regeneration of body parts and their interaction with the immune response is a poorly understood aspect of earthworm biology. Consequently, we aimed to study the mechanisms of innate immunity during regeneration in Eisenia andrei earthworms. In the course of anterior and posterior regeneration, we documented the kinetical aspects of segment restoration by histochemistry. Cell proliferation peaked at two weeks and remitted by four weeks in regenerating earthworms. Apoptotic cells were present throughout the cell renewal period. Distinct immune cell (e.g., coelomocyte) subsets were accumulated in the newly-formed blastema in the close proximity of the apoptotic area. Regenerating earthworms have decreased pattern recognition receptors (PRRs) (e.g., TLR, except for scavenger receptor) and antimicrobial peptides (AMPs) (e.g., lysenin) mRNA patterns compared to intact earthworms. In contrast, at the protein level, mirroring regulation of lysenins became evident. Experimental coelomocyte depletion caused significantly impaired cell divisions and blastema formation during anterior and posterior regeneration. These obtained novel data allow us to gain insight into the intricate interactions of regeneration and invertebrate innate immunity.     

Production of 225Ac and 223Ra by irradiation of Th with accelerated protons

The possibility of producing ²²⁵Ac and ²²³Ra by irradiation of natural ²³²Th with medium-energy protons was examined. Thorium foils were irradiated with 90-, 110-, and 135-MeV protons at the accelerator of the Institute for Nuclear Research, Russian Academy of Sciences, in Troitsk (Moscow oblast). The cumulative production cross sections for ²²⁵Ac were 6.7 ± 0.9, 9.8 ± 1.9, and 13.9 ± 1.5 mb, and for ²²⁷Th (²²³Ra precursor), 43 ± 5, 37 ± 6, and 35 ± 4 mb, respectively. Based on the experimental data and theoretical calculations, the possible yields of ²²⁵Ac and ²²³Ra in irradiation of thick thorium targets at various accelerators were determined. An efficient procedure was suggested for isolating the products from the irradiated targets: ²²⁵Ac, by liquid extraction and extraction chromatography, and ²²³Ra, by sublimation from a thorium-lanthanum melt followed by thermochromatographic separation in metallic titanium columns and extraction-chromatographic isolation of radium. The procedure allows production of large (units of curies) amounts of radiochemically pure ²²⁵Ac and ²²³Ra, which is promising for wide use of these radionuclides in nuclear medicine.     

Knowledge management for occupational safety,health, and ergonomics

The critical challenge for occupational safety, health, and ergonomics (OSHE) in contemporary industry is management of the existing individual (personal) knowledge, structural knowledge (i.e., knowledge codified into manuals, reports, databases, and data warehouses), and organizational knowledge (activity of learning within the organization) in the vast domain of practical applications. Therefore, the principles and tools of knowledge management (KM) should be used to facilitate the management of OSHE. The authors discuss the requirements for effective knowledge management, review the existing models of KM and their structures, and introduce a model for KM in OSHE. The proposed model of KM for OSHE is based on a strategy that establishes knowledge as the central resource to achieve the goals of OSHE management. The model includes the systems of organizational knowledge, organizational learning (knowledge creation, distribution, elaboration, and consolidation), development of knowledge workers, KM processes (review, conceptualization, reflection, and acting), and relevant information‐technologies. © 2006 Wiley Periodicals, Inc. Hum Factors Man 16: 309–319, 2006.     

Functionalizing nanocrystalline metal oxide electrodes with robust synthetic redox proteins

De novo designed synthetic redox proteins (maquettes) are structurally simpler, working counterparts of natural redox proteins. The robustness and adaptability of the maquette protein scaffold are ideal for functionalizing electrodes. A positive amino acid patch has been designed into a maquette surface for strong electrostatic anchoring to the negatively charged surfaces of nanocrystalline, mesoporous TiO(2) and SnO(2) films. Such mesoporous metal oxide electrodes offer a major advantage over conventional planar gold electrodes by facilitating formation of high optical density, spectroelectrochemically active thin films with protein loading orders of magnitude greater (up to 8 nmol cm(-2)) than that achieved with gold electrodes. The films are stable for weeks, essentially all immobilized-protein display rapid, reversible electrochemistry. Furthermore, carbon monoxide ligand binding to the reduced heme group of the protein is maintained, can be sensed optically and reversed electrochemically. Pulsed UV excitation of the metal oxide results in microsecond or faster photoreduction of an immobilized cytochrome and millisecond reoxidation. Upon substitution of the heme-group Fe by Zn, the light-activated maquette injects electrons from the singlet excited state of the Zn protoporphyrin IX into the metal oxide conduction band. The kinetics of cytochrome/metal oxide interfacial electron transfer obtained from the electrochemical and photochemical data obtained are discussed in terms of the free energies of the observed reactions and the electronic coupling between the protein heme group and the metal oxide surface.     

Sorption of radiostrontium from liquid rubidium metal

Sorption of radiostrontium (in particular, ⁸²Sr) from liquid rubidium metal on various inorganic sorbents (metals and oxides) was studied. The temperature dependence and dynamics of the adsorption were studied, and the observed relationships were accounted for. The procedure developed allows efficient isolation of ⁸²Sr from Rb targets after their irradiation with accelerated protons. Various versions of the procedure are considered, and prospects for the development of a new high-performance process for preparing ⁸²Sr, in particular, using circulating Rb targets, were discussed.     

The relationship between work organization and workforce agility in small manufacturing enterprises

Organizational agility requires development of an adaptable workforce that is able to deal with unexpected and dynamic changes in the business environment. However, little research has been done on the attributes and characteristics of workforce agility. Even less is known about what organization characteristics are conducive to the agile performance of employees. The main goal of this study was to explore the effect of agile strategies on work organization and employees' performance. A total of 41 managers, 82 office workers, and 52 production workers from six small manufacturing companies participated in the study. Three questionnaires, including Agility Strategy Scale, Work Organization Scale, and Workforce Agility Scale, were used for the purpose of data collection. The results support a hypothesized relationship between management strategies focused on agility development, work characteristics, and workforce agility. The results also reveal that autonomy at work is one of the most important predictors of workforce agility. A combination of job demands and job uncertainty had a significant effect on workforce agility. The study also suggests that developing strong cooperative relationships within an organization and with customers and suppliers promotes workforce agility in small manufacturing enterprises.