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Since August 2001, German radiation protection law is governed by a new Radiation Protection Ordinance, implementing two new Euratom Directives and taking into account new scientific developments, which provides a comprehensive basis for the protection of man and the environment. The Ordinance has been completely re-structured; however, it is still a very complex piece of legislation comprising 118 provisions and 14 annexes, some of them highly technical. Reduced dose limits for occupationally exposed persons and members of the public, a detailed provision on clearance of radioactive substances, a new part aiming at the protection of man and the environment against ionising radiation emanating from natural sources, and regulations dealing with the protection of consumers in connection with the addition of radioactive substances to consumer goods are some of the centre pieces of the new legislation which shall contribute significantly to the further prevention or at least minimisation of the adverse effects of radiation exposure.

Isothermal sections at 800, 1000, and 1150 °C as well as a tentative partial liquidus surface of the ternary Fe–Al–Zr system were established by means of electron-probe microanalysis, X-ray diffraction, differential thermal analysis, and light-optical as well as scanning electron microscopy. The most prominent features of the ternary phase diagram are the extended homogeneity ranges of the Laves phases. By continuous substitution of Fe by Al, the structure changes three times starting from the cubic C15 structure of Fe2Zr to hexagonal C14 (λ1) back to cubic C15 (λ2) and again to hexagonal C14 (Al2Zr). The various Laves phase fields are separated by very small two-phase fields. Besides the Laves phases λ1and λ2, three more ternary intermetallic phases were found, whose homogeneity ranges have been determined for the first time. In addition, new results concerning the homogeneity ranges of intermetallic phases in the binary subsystems Fe–Al and Al–Zr are reported. The solubilities of the third components in the binary phases are found to be generally very low with the exception of the Laves phases. As a consequence, extended two-phase fields between the Fe(Al) solid solution and Laves phase or between Fe(Al) solid solution and the ternary ThMn12-type phase τ1are formed.

The liquidus surface of the Al –Fe –Ti system has been reexamined. 34 different alloys have been studied by differential thermal analysis, and the temperatures of invariant reactions have been determined. By examining the as-cast samples by optical microscopy, X-ray diffraction and energy-dispersive spectrometry in a scanning electron microscope, the crystal structures and chemical compositions of the primary phases and two-phase aggregates have been established. In some cases, additional investigations were carried out in the transmission electron microscope. From the combined results of these investigations the solidification paths of the alloys were established leading to a revised representation of the liquidus surface of the Al –Fe –Ti system. A reaction scheme has been set up which shows phase equilibria that are consistent with previous solid-state isothermal sections.

In this paper we present an overview of agent-based models that are used to simulate mechanical and physiological phenomena in cells and tissues, and we discuss underlying concepts, limitations, and future perspectives of these models. As the interest in cell and tissue mechanics increase, agent-based models are becoming more common the modeling community. We overview the physical aspects, complexity, shortcomings, and capabilities of the major agent-based model categories: lattice-based models (cellular automata, lattice gas cellular automata, cellular Potts models), off-lattice models (center-based models, deformable cell models, vertex models), and hybrid discrete-continuum models. In this way, we hope to assist future researchers in choosing a model for the phenomenon they want to model and understand. The article also contains some novel results.

A nickel alloy of a composition similar to that of the nickel based superalloy Inconel alloy 718 (IN718) was produced with the electron beam melting (EBM) process developed by Arcam AB. The microstructures of the as processed and heat treated material are similar to that of conventionally produced IN718, except that the EBM material showed some porosity and the dphase did not dissolve during the solution heat treatment because the temperature of 1000°C apparently was too low. Mechanical testing of the layer structured material, parallel and perpendicular to the built layers, revealed sufficient strength in both directions. However, it showed only limited elongation when tested perpendicular to the built layers due to local agglomerations of pores. Otherwise, data for the hardness, Young's modulus, 0·2 yield tensile strength and ultimate tensile strength match those recommended for IN718.

After 5 years of development, the European College of Veterinary Clinical Pathology (ECVCP) was formally recognized and approved on July 4, 2007 by the European Board of Veterinary Specialisation (EBVS), the European regulatory body that oversees specialization in veterinary medicine and which has approved 23 colleges. The objectives, committees, basis for membership, constitution, bylaws, information brochure and certifying examination of the ECVCP have remained unchanged during this time except as directed by EBVS. The ECVCP declared full functionality based on the following criteria: 1) a critical mass of 65 members: 15 original diplomates approved by the EBVS to establish the ECVCP, 37 de facto diplomates, 7 diplomates certified by examination, and 5 elected honorary members; 2) the development and certification of training programs, laboratories, and qualified supervisors for residents; currently there are 18 resident training programs in Europe; 3) administration of 3 annual board-certifying examinations thus far, with an overall pass rate of 70; 4) European consensus criteria for assessing the continuing education of specialists every 5 years; 5) organization of 8 annual scientific congresses and a joint journal (with the American Society for Veterinary Clinical Pathology) for communication of scientific research and information; the College also maintains a website, a joint listserv, and a newsletter; 6) collaboration in training and continuing education with relevant colleges in medicine and pathology; 7) development and strict adherence to a constitution and bylaws compliant with the EBVS; and 8) demonstration of compelling rationale, supporting data, and the support of members and other colleges for independence as a specialty college. Formal EBVS recognition of ECVCP as the regulatory body for the science and practice of veterinary clinical pathology in Europe will facilitate growth and development of the discipline and compliance of academic, commercial diagnostic, and industry laboratories in veterinary clinical pathology. Future needs are in developing sponsorship for resident positions, increasing employment opportunities, increasing compliance with laboratory, training, and continuing education standards, and advancing relevant science and technology.

Background: There are numerous methods for analyzing creatinine concentration in plasma, including the Jaffé alkaline picrate method in various modifications, enzymatic tests, and chromatographic methods. Objective: The purpose of this study was to evaluate whether an enzymatic method could replace a Jaffé method for routine creatinine measurements in plasma from dogs, rats, and mice. The enzymatic method and a compensated Jaffé method were tested against a high-pressure liquid chromatography (HPLC) method, regarded as the gold standard for creatinine measurement. Methods: Heparinized plasma samples were obtained from 20 beagle dogs, 20 Wistar rats, and 20 CD1-strain mice. The 2 test kits (Roche Diagnostics), Creatinine Jaffé Compensated and the enzymatic Creatinine Plus Version 2 reagent, were used on a Cobas Integra 400. The Jaffé compensated method used a calibration adjustment of ?18 ?mol/L to correct for the protein matrix in serum and plasma. The HPLC method was an isocratic method using a weak cation-exchange column following protein precipitation. Results: Creatinine concentrations obtained using the enzymatic and the Jaffé methods differed significantly from the results obtained by the HPLC method. For dog plasma, mean values of 61.2, 61.8, and 67.8 ?mol/L were obtained by the compensated Jaffé, enzymatic, and HPLC methods, respectively. In the rat, respective mean values were 26.7, 21.9, and 23.0 ?mol/L, and in the mouse, respective mean values were 14.2, 5.4, and 9.2 ?mol/L. Conclusion: The enzymatic method can replace the Jaffé method for plasma creatinine determination in dogs, rats, and mice because results from the enzymatic method were closer to HPLC values than were those of the Jaffé method.

This paper describes the extraction of hemicellulosic oligosaccharides from spruce, using microwave or steam treatment that can be used for the production of polymers, replacing fossil-based polymers, e.g., hydrogels. The highest yield of oligosaccharides, measured as mannan, was 70% obtained with treatment in the microwave oven at 200 °C for 5 min. The amount of oligosaccharides extracted was 12.5 g per 100 g of dry wood. The molecular weights of some selected samples were analyzed using fast protein liquid chromatography and size exclusion chromatography and time-of-flight matrix-assisted laser desorption ionization. Recovered oligosaccharides following steam treatment at 200 °C for 2 min had a mean molecular weight of 3400 g/mol with a maximum weight of 12000 g/mol. Higher severity, i.e., increased temperature (>200 °C) and residence time, resulted in lower mean molecular weights and yield. Oligosaccharides with higher mean molecular weights were obtained at lower severity, but the yield was considerably lower. The feasibility of using the extracted hemicellulosic oligosaccharides from spruce for the synthesis of hydrogels was demonstrated.

Abstract: The phase diagram of the binary Fe-Zr system was redetermined by differential thermal analysis (DTA), electron-probe microanalysis (EPMA), x-ray diffraction (XRD), and metallography in the whole range of compositions. The stable intermetallic phases of the binary system are the cubic and the hexagonal polymorphs of the Fe2Zr Laves phase and the Zr-rich phases FeZr2 and FeZr3. While the cubic polymorph of the Laves phase is the stable structure at the stoichiometric Fe2Zr composition, the hexagonal C36-type polymorph of the Laves phase is a high-temperature phase that is found at Zr concentrations as low as 26.6 at.%. The Zr-rich phases FeZr2 and FeZr3 have small homogeneity ranges of about 0.5 at.%. FeZr2 is a high-temperature phase, stable between 780 and 951 °C. FeZr3 decomposes peritectoidally at 851 °C. The frequently reported phase Fe23Zr6 (Fe3Zr) is found not to be an equilibrium phase of the binary system.

Generation of Chinese Hamster Ovary (CHO) cell lines stably expressing green fluorescent protein (GFP) was achieved using a plasmid vector that encoded the red-shifted pCX-xGFP under the control of a strong hybrid promoter composed of a CMV enhancer and a β-actin/β-globin gene promoter. Cotransfection of the promoter-less pSV2-Neo helper plasmid transmitting neomycin resistance was followed by selection with the antibiotic G418. Constitutive GFP expression could be visualized in living and fixed cells using fluorescence spectroscopy, fluorescence microscopy, and flow cytometry. DNA repair-proficient (AA8) and deficient (UV5) CHO strains were used for survival tests after UVC irradiation. Cells carrying the GFP construct (AA8-pGFP, UV5-pGFP) show the same response to UV irradiation (colony forming ability) as their nontransformed parental cell lines (AA8, UV5). Using GFP as a marker for cell viability, cells were harvested after certain postirradiation growth periods and the numbers of GFP expressing cells and fluorescence intensities were determined by FACS analysis. Generally, GFP fluorescence in irradiated cells is not seen when cell membranes are damaged (leak-out of the soluble GFP). Irradiated cells without membrane damage express GFP continuously (leading to a dose-dependent increase in GFP contents).

Different conditions for establishing a cell culture system for generation of AA‐amyloid were investigated. The most effective system was based on peritoneal macrophages from CBA/J mice that had received repeated injections of Hammersten casein, with subsequent cultivation of the cells at high density, high levels of acute phase serum, and neutral pH. Staining with Congo red, thioflavin T, and anti‐AA revealed amyloid‐like structures associated with macrophage clusters. The structures increased in number and size from day 2 to 6 of cell cultivation. The concentration of apoSAA in the culture medium fell markedly in the amyloid‐producing cell cultures, while the SAP concentration was not reduced. The described cell culture system can be useful in studies of the influence of chaperone molecules and other factors on the formation and degradation of amyloid fibrils.

Abstract: An extensive experimental investigation of the Fe-Al-Ti system by metallography, microprobe analysis, and XRD on quenched specimens and on diffusion couples is presented. Two isothermal sections at 800 and 1000 �C were established; they differ substantially from the existing (800 �C) or partly determined (1000 �C) diagrams. From these results, existence of the τ1 phase (Fe2AlTi) can be ruled out. Existence of the ternary compounds, τ2 (Al2FeTi) and τ3 (Al22Fe3Ti8), is confirmed. The composition limits of both phases were determined; they differ considerably from those given in earlier reports. The τ2 phase apparently exists in a cubic and a tetragonal polymorph, depending on composition. The cubic form exists at high titanium contents. At 1000 �C, the two polymorphs are separated by a miscibility gap. At compositions where the “X phase” (Al69Fe25Ti6) was previously reported, single-phase samples were obtained at both temperatures. From the present results, there is no evidence to assume that this is a new ternary phase rather than the ternary homogeneity range of the Al3Fe phase. In addition, extensions of the binary intermetallic phases into the ternary system were determined.

Results of in vitro and ex vivo experiments with a newly developed LDL-binding material are presented. This material consists of macroporous bead cellulose which is capable to bind selectively LDL. LDL-cholesterol is considerably decreased after contacts of plasma or serum samples with this bead cellulose. On the other hand high density lipoproteins (HDL) and other plasma components (proteins, enzymes, electrolytes, and metabolic substances) remained high or unchanged. Triglycerides (TG) - transported by very low density lipoproteins - are also bound up to a certain degree. 1 g of the adsorbent wet mass binds at least 20 mg cholesterol. The capacity suffices to decrease two- to threefold increased cholesterol and LDL plasma levels to the low normal range following passage of the senvenfold plasma volume through two the three LDL adsorbent columns (results of perfusion experiments). In vitro and dog experiments revealed only slight drops of the hemolytic capacities of the classic complement pathway and moderate decreases of the alternative one. But no detectible side effects were noticed in the dog experiments.

Three groups of patients suffering from acute attacks or progressive multiple sclerosis (MS) are under investigation. First results revealed remarkable clinical improvements of patients with acute attacks in the groups treated by therapeutic plasma exchange (TPE) and immunoadsorption (IA). Only slight or no improvements were seen in the patients of the control group treated only with steroids.Plasma protein levels (IgG, IgM, IgA, fibrinogen) were considerably reduced in patients of the TPE group after each treatment procedure as expected. The same holds true concerning the total hemolytic capacities (THC) of the complement of the classic (CP) and the alternative (AP) pathway. On the other hand in the IA group only slight decreases of plasma proteins (about 20%) were observed, but the behaviour of THC's were quite similar than those seen in the patients of the TPE group. The THC decreases in both groups can be explained by removal of all complement factors (TPE group) or by the adsorption of single factors (IA group) of both complement pathways according to earlier in vitro investigations. The THC decreases in patients of both groups suffering from acute MS attacks could mean an "antiinflammatory" effect and could - at least partially - contribute to the clinical improvements of these patients.

The procoagulant protein F.VIII:C is noncovalently bound to von Willebrand factor (vWF) to give the factor VIII macromolecular complex. New highly purified preparations of isolated human F.VIII:C, devoid of vWF and about 500,000-fold purified, were administered to hemophilia A and von Willebrand disease (vWD) dogs to determine their hemostatic effectiveness and survival in the circulation. Two preparations of F.VIII:C were used: peak 1, with active components of Mr 185,000-280,000, and peak 2, with a single component of Mr 170,000. In hemophilic dogs, with no plasma F.VIII:C but normal vWF, both preparations immediately elevated plasma F.VIII:C to expected levels, promptly stopped induced and spontaneous hemorrhages, and gave sustained plasma levels of F.VIII:C. The isolated F.VIII:C immediately complexed with endogenous vWF in hemophilic plasma and was eliminated exponentially, with a half-life (t1/2) of about 9 hr. Survival of peak 2 F.VIII:C was longer than that of peak 1 material. In contrast, F.VIII:C complexed to vWF in a therapeutic concentrate administered to hemophilic dogs was eliminated biexponentially with first-phase t1/2 of 3.2 hr and second-phase t1/2 of 9 hr. In vWD dogs with no vWF and reduced F.VIII:C levels, the isolated F.VIII:C produced supernormal levels of F.VIII:C without effect on induced bleeding. It was rapidly eliminated from plasma with a t1/2 of about 1 hr, as was the complexed F.VIII:C in the concentrate. These data indicate that isolated F.VIII:C promptly complexes with vWF and in this form is highly effective in controlling hemophilic hemorrhages with good survival in plasma. Without endogenous vWF with which to complex, the F.VIII:C is promptly eliminated.

The aim was to describe the microbiology of surgically treated infective native (mycotic) aortic aneurysms (INAAs), and associated survival and development of infection-related complications (IRCs).

Summary In this experiment arterial grafts were implanted in 24 young rats and venous grafts in 25 animals. The average increase in length of the grafts was 76.6% for arteries and 50.8% for veins after a mean of 263 days. The patency rate of the grafts was 95.6%, and that of the venous grafts 84%. There were aneurysmal changes in 43 of the venous grafts, but no such changes were found with the arterial grafts. The anastomotic sites showed no stenosing alterations. According to our measurements the implanted grafts develop in keeping with the totalorganism.