3,074 research outputs found

    Krefelderski test - novi eksperimentalni postupak za proučavanje toksičnosti kemikalija

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    During the last years, skin compatibility of textiles has gained importance for consumers. Therefore, the development of suitable test methods for the evaluation of skin compatibility is a vital challenge. The fundamental requirements for these test methods are low experimental complexity combined with minor costs. The Cilitatetest has been developed for the cosmetic and pharmaceutics industry. Due to the optical measurement of the number of living microorganisms, this method is not suitable for colored or heterogeneous samples. However, using a calorimetric detection, these problems are resolved. This method allows very sensitive detection of the metabolism of the microorganism. The presence of any toxic substance results in a reduction of the heat of metabolism.Kompatibilnost tekstila prema koži postajala je tijekom posljednjih godina sve važnija potrošačima. Zato je razvoj prikladnih postupaka ispitivanja za prosudbu kompatibilnosti s kožom primjeran izazov. Osnovni zahtjev postavljen za ove postupke ispitivanja jest eksperimentalna jednostavnost povezana s nižim troškovima. Ispitivanje trepetljikašima razvijeno je za kozmetičku i farmaceutsku industriju. Zbog optičkog mjerenja broja živih mikroorganizama taj postupak nije prikladan za obojene ili heterogene uzorke. Međutim, ti problemi su riješeni primjenom kalorimetijskog otkrivanja. Taj postupak otkrivanja omogućuje vrlo osjetljivo prepoznavanje metabolizma mikroorganizama. Postojanje bilo koje otrovne tvari znači smanjenje topline metabolizm

    Methods and apparatus for the on-site production of hydrogen peroxide

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    Methods, apparatus, and applications for the on-site production of hydrogen peroxide are described. An embodiment of the apparatus comprises at least one anolyte chamber coupled to at least one anode, at least one catholyte chamber, wherein the at least one catholyte chamber is coupled to at least one cathode, at least one anode membrane and at least one cathode membrane, wherein the anode membrane is adjacent to the at least one anode, wherein the cathode membrane is adjacent to the at least one cathode, at least one central chamber disposed between the at least one anolyte chamber and the at least one catholyte chamber. Hydrogen peroxide is produced by reduction of an oxygen-containing gas at the cathode

    Isolation and structural determination of {(1,1,2,2-tetracyano-1,2-ethanediyl)bis[imino(cyanomethylene)]}bis-(cyanamide) ion(2--), [C12N12]2--, a new cyanocarbon

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    Journal ArticleThe oxidative degradation of [N(PPh3)2]3[Mnilll(CN)6] leads to the isolation of the unprecedented [C12N12]2- dianion, which is characterized by single-crystal X-ray diffraction and spectroscopic techniques

    Structure and physical properties of hexacyanomanganate(IV), [MnIV(CN)6]2-

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    Journal ArticleHydrolytically unstable d3 [MnI V(CN)6]2- as the [N(PPh3)2]+ salt is crystallographically, spectroscopically, and magnetically characterized

    Structural and functional investigation of ABC transporter STE6-2p from Pichia pastoris reveals unexpected interaction with sterol molecules

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    Adenosine triphosphate (ATP)-binding cassette (ABC) transporters are multidomain transmembrane proteins, which facilitate the transport of various substances across cell membranes using energy derived from ATP hydrolysis. They are important drug targets since they mediate decreased drug susceptibility during pharmacological treatments. For the methylotrophic yeast Pichia pastoris, a model organism that is a widely used host for protein expression, the role and function of its ABC transporters is unexplored. In this work, we investigated the Pichia ABC-B transporter STE6-2p. Functional investigations revealed that STE6-2p is capable of transporting rhodamines in vivo and is active in the presence of verapamil and triazoles in vitro. A phylogenetic analysis displays homology among multidrug resistance (MDR) transporters from pathogenic fungi to human ABC-B transporters. Further, we present high-resolution single-particle electron cryomicroscopy structures of an ABC transporter from P. pastoris in the apo conformation (3.1 Å) and in complex with verapamil and adenylyl imidodiphosphate (AMP-PNP) (3.2 Å). An unknown density between transmembrane helices 4, 5, and 6 in both structures suggests the presence of a sterol-binding site of unknown function

    Variability in disease phenotypes within a single PRNP genotype suggests the existence of multiple natural sheep scarpie strains within Europe

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    Variability of pathological phenotypes within classical sheep scrapie cases has been reported for some time, but in many instances it has been attributed to differences in the PRNP genotype of the host. To address this issue we have examined by immunohistochemistry (IHC) and Western blotting (WB) for the disease-associated form of the prion protein (PrPd), the brains of 23 sheep from five European countries, all of which were of the same ARQ/ARQ genotype. As a result of IHC examinations, sheep were distributed into five groups with different phenotypes and the groups were the same regardless of the scoring method used, ‘long’ or ‘short’ PrPd profiling. The groups made did not respond to the geographical origin of the cases and did not correlate with the vacuolar lesion profiles, which showed a high individual variability. Discriminatory IHC and WB methods coincided to detect a ‘CH1641-like’ case but otherwise correlated poorly in the classification of disease phenotypes. No other polymorphisms of the PRNP gene were found that could account for the pathological differences, except perhaps for a sheep from Spain with a mutation at codon 103 and a unique pathological phenotype. Preliminary evidence indicates that those different IHC phenotypes correlate with distinct biological properties on bioassay, suggesting that they are indicative of strain diversity. We therefore conclude that natural scrapie strains exist and that they can be revealed by detailed pathological examinations, which can be harmonized between laboratories to produce comparable results

    A Catalog of Architectural Tactics for Cyber-Foraging

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    Mobile devices have become for many the preferred way of interacting with the Internet, social media and the enterprise. However, mobile devices still do not have the computing power or battery life that will allow them to perform effectively over long periods of time or for executing applications that require extensive communication or computation, or low latency. Cyber-foraging is a technique enabling mobile devices to extend their computing power and storage by offloading computation or data to more powerful servers located in the cloud or in single-hop proximity. This paper presents a catalog of architectural tactics for cyber-foraging that was derived from the results of a systematic literature review on architectures for cyber-foraging systems. Elements of the architectures identified in the primary studies were codified in the form of Architectural Tactics for Cyber-Foraging. These tactics will help architects extend their design reasoning towards cyber-foraging as a way to support the mobile applications of the present and the future

    Iridium complexes of the conformationally rigid IBioxMe4Ligand : hydride complexes and dehydrogenation of cyclooctene

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    A method for accessing the formally 14 VE iridium(III) hydride fragment {Ir(IBioxMe4)2(H)2}+ (2), containing the conformationally rigid NHC ligand IBioxMe4, is reported. Hydrogenation of trans-[Ir(IBioxMe4)2(COE)Cl] (1) in the presence of excess Na[BArF4] leads to the formation of dimeric [{Ir(IBioxMe4)2(H)2}2Cl][BArF4] (3), which is structurally fluxional in solution and acts as a reservoir of monomeric 2 in the presence of excess halogen ion abstractor. Stable dihydride complexes trans-[Ir(IBioxMe4)2(2,2′-bipyridine)(H)2][BArF4] (4) and [Ir(IBioxMe4)3(H)2][BArF4] (5) were subsequently isolated through in situ trapping of 2 using 2,2′-bipyridine and IBioxMe4, respectively, and fully characterized. Using mixtures of 3 and Na[BArF4] as a latent source of 2, the reactive monomeric fragment’s reactivity was explored with excess ethylene and cyclooctene, and trans-[Ir(IBioxMe4)2(C2H4)2][BArF4] (6) and cis-[Ir(IBioxMe4)2(COD)][BArF4] (7) were isolated, respectively, through sacrificial hydrogenation of the alkenes. Complex 6 is notable for the adoption of a very unusual orthogonal arrangement of the trans-ethylene ligands in the solid state, which has been analyzed computationally using energy and charge decomposition (EDA-NOCV). The formation of 7 via transfer dehydrogenation of COE highlights the ability to partner IBioxMe4 with reactive metal centers capable of C–H bond activation, without intramolecular activation. Reaction of 7 with CO slowly formed trans-[Ir(IBioxMe4)2(CO)2][BArF4] (8), but the equivalent reaction with bis-ethylene 6 was an order of magnitude faster, quantifying the strong coordination of COD in 7

    Agile at scale : a summary of the 8th International Workshop on Large-Scale Agile Development

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    The Large-Scale Agile Development workshop explored the main research challenges in large-scale software development. We considered multi-site organisations with large-scale projects that include a large number of teams adopting agile methods. Such topics include inter-team coordination, knowledge sharing, large project organisation, agile transformation, agile teamwork quality, project models that facilitate several self-organising teams, and practices for scaling agile methods. We accepted five full research papers, which are included in this volume. The accepted papers report empirical research studies using surveys, observations and case studies. Also, an interactive online discussion session was conducted to compare the two approaches, SAFe and Spotify. The workshop participants, which were around a hundred people, joined this discussion to compare the two approaches and suggest some future research questions about the hybridisation of SAFe and Spotify. This workshop summary contributes as a current snapshot of research along with some results from an interactive discussion about SAFe and Spotify
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