Quality and timeliness in medical laboratory testing

In terms of testing, modern laboratory medicine can be divided into centralized testing in central laboratories and point-of-care testing (POCT). Centralized laboratory medicine offers high-quality results, as guaranteed by the use of quality management programs and the excellence of the staff. POCT is performed by clinical staff, and so such testing has moved back closer to the patient. POCT has the advantage of shortening the turnaround time, which potentially benefits the patient. However, the clinical laboratory testing expertise of clinical staff is limited. Consequently, when deciding which components of laboratory testing must be conducted in central laboratories and which components as POCT (in relation to quality and timeliness), it will be medical necessity, medical utility, technological capabilities and costs that will have to be ascertained. Provided adequate quality can be guaranteed, POCT is preferable, considering its timeliness, when testing vital parameters. It is also preferred when the central laboratory cannot guarantee the delivery of results of short turn-around-time (STAT) markers within 60 or (even better) 30 min. POCT should not replace centralized medical laboratory testing in general, but it should be used in cases where positive effects on patient care have been clearly demonstrated.     

Desoxy-nitrozucker. 13. Mitteilung. Herstellung ungeschützter und partiell geschützter 1-Desoxy-1-nitro-D-aldosen sowie Röntgenstrukturanalysen einiger ihrer Vertreter

Preparation of Unprotected and Partially Protected 1-Deoxy-1-nitro-D -aldoses and Some Representative X-Ray Structure Analyses The unprotected and partially protected 1-deoxy-1-nitro derivatives of α-and β-D -glucopyranose (see 15 and 14 ), β-D -mannopyranose (see 16 ), N-acetyl-β-D -glucosamine (see 17 ), β-D -galactofuranose (see 19 ), β-D -ribofuranose (see 20 ), α-D -arabinofuranose (see 21 ), 4,6-O-benzylidene-β-D -glucose (see 40 ), N-acetyl-4,6-O-benzylidene-β-D -glucosamine (see 41 ), and 4,6-O-benzylidene-β-D -galactose (see 42 ) were prepared by ozonolysis of the corresponding nitrones which were obtained from the acid-catalyzed reaction of p-nitrobenzaldehyde with the hydroxylamine 4 , the unprotected oximes 3 and 5–9 and the 4,6-O-benzylidene oximes 35–37 , respectively (Schemes 1–3). The gluco- and manno-nitrones 10 and 12 were isolated, and their ring size and their anomeric and (E/Z) configurations were determined by NMR spectroscopy and by their transformation into their corresponding nitro derivatives. The structure of the deoxynitroaldoses were determined by NMR spectroscopy, polarimetry, and, in the case of 14 , 16 , and 17 , by formation of the 4,6-O-benzylidene ( 14 → 40 ) or 4,6-O-isopropylidene ( 16 → 43 , 17 → 23 ) derivatives (Scheme 3). Acetylation of the nitroglucopyranose 14 , the 2-acetamido-nitroglucopyranose 17 , and the nitrogalactofuranose 19 gave the crystalline peracetylated nitroaldoses 22 , 24 , and 45 , respectively (Scheme 4, Figs. 1 and 3); acetylation of the nitromannopyranose 16 gave the nitro-arabino-glycal 44 (Scheme 4). The structure of the peracetylated nitroglucopyranose 22 , the nitroglucosamine 25 , the nitrogalactofuranose 45 , and the nitroribofuranose 20 were confirmed by X-ray analysis (Figs. 1 4). In all cases, including the β-D -glucopyranose derivative 22 , considerably shortening of the (endocyclic) C(1)-O bond was observed. Base-catalyzed anomerization of the β-D -configurated nitroglucopyranose 14 , the nitromannopyranose 16 , the benzylidene acetal 40 of nitroglucose, and the 2,3,4,6-tetraacetylated glucosamine derivative 24 gave the corresponding nitro-α-D -aldoses 15 , 26 , 47 , and 25 , respectively (Scheme 4).     

TEM investigation of TiNx-PACVD-coatings

The wear resistance of cermet cutting tools can be remarkably increased by TiN_x coatings. These layers are deposited at substrate temperatures of 723 K, 773 K and 973 K using a plasma-assisted chemical vapour deposition (PACVD) process. TEM investigations combined with EDXS analysis and electron diffraction gave information on structure and composition of the TiN_x layers and the interface range. X-ray structure investigations were performed additionally.The structure and the chlorine content of layers and interfaces change in dependence on the deposition temperature. All coatings show a columnar structure, but the fibre diameter increases with temperature. The fine-grained TiN_x layer deposited at 723 K has the highest chlorine content, a low-developed columnar structure and a 111 texture. The coatings deposited at 773 K and 973 K contain less chlorine impurities and have a 100 preferred orientation. The fibre structures at 723 K and 773 K can be resolved into single crystallites. By TEM investigations the fibres formed at 773 K are proved to be an accumulation of neighbouring and similarly oriented crystallites. Grain size determined by X-ray analysis and fibre diameter agree with each other. Grain sizes determined more exactly from TEM images are 6 nm at 723 K, 10 nm at 773 K and 30 nm at 973 K. In the interface region the thickness and the chlorine content of this zone decreases with increasing deposition temperature and simultaneously the layer adhesion increases.Dedicated to Professor Dr. rer. nat. Dr. h.c. Hubertus Nickel on the occasion of his 65th birthday     

Dual nature of a tin-containing liquid crystalline side group homopolymer

Two tin-containing homopolymers, one liquid crystalline and the other non-mesomorphic, were synthesized and characterized by different relaxation methods (dielectric, calorimetric, NMR). The results prove the existence of two glass transition temperatures related to the dynamics of the main chain and of the liquid crystalline side group, respectively. The reason for this effect is based on a phase separation on nanometer scale.     

Energy-filtered TEM imaging and EELS study of ODS particles and argon-filled cavities in ferritic-martensitic steels

Oxide-dispersion-strengthened (ODS) ferritic-martensitic steels with yttrium oxide (Y(2)O(3)) have been produced by mechanical alloying and hot isostatic pressing for use as advanced material in fusion power reactors. Argon gas, usually widely used as inert gas during mechanical alloying, was surprisingly detected in the nanodispersion-strengthened materials. Energy-filtered transmission electron microscopy (EFTEM) and electron energy loss spectroscopy (EELS) led to the following results: (i) chemical composition of ODS particles, (ii) voids with typical diameters of 1-6 nm are formed in the matrix, (iii) these voids are filled with Ar gas, and (iv) the high-density nanosized ODS particles serve as trapping centers for the Ar bubbles. The Ar L(3,2) energy loss edge at 245 eV as well as the absorption features of the ODS particle elements were identified in the EELS spectrum. The energy resolution in the EEL spectrum of about 1.0 eV allows to identify the electronic structure of the ODS particles.     

Fissile core and Tritium-Breeding Blanket: structural materials and their requirements

High radiation resistant structural materials for fusion and fission nuclear power plants are a key issue for the development of both types of reactors. Selection criteria, elements of metallurgy of the selected materials, and the major issues as they are revealed by the results of the present development programmes, are presented. At low temperature (300 °C) ferritic/martensitic steels are suffering from He-embrittlement, associated with possible hardening due to α/α^′ unmixing. The kinetics of hardening and embrittlement versus dose, especially saturation with dose, are still open key issues, difficult to settle on the basis of a purely experimental programme. Important progress is still to be made in mastering the initial microstructure, inclusion cleanness and joining techniques of oxide dispersion strengthened steels for higher heat resistance. Physics modeling as presented in this issue should promote guidance to the understanding of the mechanisms involved, provide solutions to master the initial microstructure and phase stability, and mitigate the in-service property degradation. To cite this article: J.-L. Boutard et al., C. R. Physique 9 (2008).