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Zusammenfassung Hintergrund und Ziel Um bei kieferorthopädischen Behandlungen die Therapietreue von Kindern zu unterstützen, werden bei herausnehmbaren Apparaturen häufig Glitzerpartikel in den Kunststoff eingebettet, die Aluminium (Al) enthalten. Bei einer Tragedauer von bis zu 16 h täglich über 2–3 Jahre kann angenommen werden, dass über die Zeit Al-Ionen in den Speichel diffundieren. Ziel der Studie war es, die Freisetzung von Al-Ionen aus dem Kunststoff unter Verwendung verschiedener kieferorthopädischer Drähte zu untersuchen. Materialien und Methode Es wurden Prüfkörper (Oberfläche 5,65 cm2) aus kieferorthopädischem Kunststoff und verschiedenen Drähten angefertigt; die Hälfte enthielt Glitzerpartikel aus Aluminium. Die Prüfkörper wurden 7 Tage lang in Petrischalen mit 50 ml Korrosionsmedium (pH 2,3) gem. DIN EN ISO 10271 bei 37 °C eingelegt. Zur Quantifizierung der spezifischen Ionen in der Korrosionslösung wurde die induktiv gekoppelte Plasmamassenspektrometrie (inductively coupled plasma - mass spectrometry, ICP-MS) verwendet. Ergebnisse Die statistische Analyse zeigte einen signifikanten Unterschied in der Konzentration der Al-Ionen zwischen Proben mit und ohne Glitzerpartikel. Die Konzentrationen aus Proben mit Glitzer erreichten bis zu 14.474 μg/l Al-Ionen, Proben ohne Glitzer enthielten im Durchschnitt 1260 μg/l. Ein geringer Anteil der Al-Ionen kann aus den Legierungen der Drähte stammen. Schlussfolgerungen Es sollte untersucht werden, ob die Aluminiumkonzentration zu Gesundheitsrisiken für den Menschen führen kann. Angesichts der Befunde sollten Kieferorthopäden keine glitzerhaltigen Apparaturen anbieten, um die Aluminiumaufnahme mit dem Speichel zu minimieren. Es muss geklärt werden, ob die in der Mundhöhle vorgefundenen Bedingungen zu gleichen Ergebnissen führen wie unter den oben genannten. Gesetzliche Regelungen sollten entwickelt werden, um die Freisetzung von Aluminium aus kieferorthopädischen Produkten zu begrenzen.

Background The function of high-density lipoprotein (HDL) cholesterol may play a more important role in the prevention of cardiovascular disease compared to the concentration of the HDL. Cardiovascular diseases such as coronary artery disease (CAD) and atrial fibrillation (AF) have been linked to impaired HDL function. Purpose The aim of the present study is to assess a biochemical measure of the antioxidant function of HDL and its association with presence of CAD and AF. Methods Patients admitted for elective cardiac catheterization were recruited in this cross-sectional study. Out of 1231 participants that were included in the analyses, 727 patients had confirmed CAD (CAD group), 369 patients had no CAD (no CAD group) and 129 persons were included as a control group. HDL function was measured in sera by determination of HDL-lipid peroxidation content (HDLox) assessed by a validated fluorometric cell-free biochemical assay and was normalized for the levels of HDL cholesterol (normalized HDLox/HDL-C ratio or nHDLox; no units). Results are expressed as median with interquartile range. Associations of nHDLox with presence of CAD and AF were assessed by univariate and multivariate analyses. Results Participants in the CAD group had higher levels of nHDLox (0.80, 0.61–1.03) compared to the no CAD (0.70, 0.55–0.93) and control (0.66, 0.55–1.03, no units, p0.05) Conclusions Reduced antioxidant function of HDL (increased HDLox measured by a biochemical assay), a metric of HDL function, is increased in patients with atherosclerosis and manifested CAD and is also associated with the presence of atrial fibrillation independent of the presence of CAD. Funding Acknowledgement Type of funding sources: Public hospital(s). Main funding source(s): Medical School of Brandenburg-MHB Fontane

Various orthodontic wire compositions and configurations are present on the market for removable appliances, however, there have still been only few studies focusing on the effect of resin color and additives such as glitter on corrosion of metallic wires under different conditions. Thus, the aim of the study was to compare concentrations of released ions (aluminium, chromium, nickel) in a corrosive medium under three different conditions: non-loaded wires, loaded wires, and non-loaded wires treated with Kukis® cleaning tablets. Six different wires made of three types of steel alloy were embedded in PMMA resin leaving one centimetre of each wire emerging from the resin to come into contact with the corrosive medium. Glitter particles were added to half of the produced test specimens. For the unloaded test series, five specimens of each group were covered in a petri dish with 50 mL of corrosive medium (pH 2.3) following EN-ISO 10271 for seven days at 37 °C. The wires for the mechanically loaded test specimens overlapped the resin by 5 cm and were clamped into a time-switched electric drive for a defined period of time before the samples were taken after a testing time of 7 days. In the third group, unloaded test specimens were transferred from their petri dishes into the prepared Kukis® solution every 24 h before being stored in the corrosive medium. Inductively coupled plasma mass spectrometry (ICP-MS) was used to quantify the specific ions in the corrosive solution. Statistical analysis showed that the mechanical loading of all wires could significantly raise the diffusion of ions into the corrosive medium. The colour of the resin did not affect the concentration of the released ions. The Kukis® cleaning tabs could not lower the corrosion of the tested metals, as some of the wires were corroded even more using the brace cleanser. Glitter-containing test specimens showed significantly higher amounts of aluminium. Mechanical loading as well as the presence of glitter particles in the resin significantly affected ion concentrations.

We have used discrete polyoxopalladates(II) (POPs) of the MPd12X8 nanocube- and Pd15X10 nanostar-types (M = central metal ion, X = capping group) as molecular precursors (diameter ca. 1 nm) for the formation of supported (SBA-15) metallic nanoparticles. These materials proved to be highly active in the hydrogenation of o-xylene. The characterization of such hydrogenation catalysts revealed that the average size of the resulting alloy particles is quite uniform with diameters ranging from 1 to 3 nm (indicating little to no agglomeration). The central transition-metal ion M n+ (MnII, FeIII, CoII, NiII, CuII, ZnII, PdII) in the POP structure and also the nature of the capping group (AsO43-, SeO32-, PO43-, phenyl-AsO32-) influence the resulting catalytic performance.

International audience; We report on the synthesis and structural characterization of the giant discrete and neutral molecular disk, [Pd40O24(OH)16{(CH3)2AsO2}16] (Pd40), comprising a 40-palladium-oxo core that is capped by 16 dimethylarsinate moieties, resulting in a palladium-oxo cluster (POC) with a diameter of ~2 nm. Pd40, which is the largest neutral Pd-based oxo-cluster, can be isolated either as a discrete species or constituting a 3D H-bonded organic-inorganic framework (HOIF) with a 12-tungstate Keggin ion [SiW12O40] 4or [GeW12O40] 4-. 1 H and 13 C NMR as well as 1H-DOSY NMR studies indicate that Pd40 is stable in aqueous solution, which is also confirmed by ESI-MS studies. Pd40 was also immobilized on a mesoporous support (SBA15) followed by the generation of size-controlled Pd-nanoparticles (diameter ~2-6 nm, as based on HR-TEM), leading to an effective heterogeneous hydrogenation catalyst for the transformation of various arenes to saturated carbocycles.

Upon biofilm formation, production of extracellular matrix components and alteration in physiology and metabolism allows bacteria to build up multicellular communities which can facilitate nutrient acquisition during unfavorable conditions and provide protection towards various forms of environmental stresses to individual cells. Thus, bacterial cells become tolerant against antimicrobials and the immune system within biofilms. In the current study, we evaluated the antibiofilm activity of the macrolides clarithromycin and azithromycin. Clarithromycin showed antibiofilm activity against rdar (red, dry and rough) biofilm formation of the gastrointestinal pathogen Salmonella typhimurium ATCC14028 Nalr at 1.56 μM subinhibitory concentration in standing culture and dissolved cell aggregates at 15 μM in a microaerophilic environment suggesting that the oxygen level affects the activity of the drug. Treatment with clarithromycin significantly decreased transcription and production of the rdar biofilm activator CsgD, with biofilm genes such as csgB and adrA to be consistently downregulated. While fliA and other flagellar regulon genes were upregulated, apparent motility was downregulated. RNA sequencing showed a holistic cell response upon clarithromycin exposure, whereby not only genes involved in the biofilm-related regulatory pathways, but also genes that likely contribute to intrinsic antimicrobial resistance, and the heat shock stress response were differentially regulated. Most significantly, clarithromycin exposure shifts the cells towards an apparent oxygen- and energy-depleted status, whereby the metabolism that channels into oxidative phosphorylation is downregulated, and energy gain by degradation of propane 1,2-diol, ethanolamine and L-arginine catabolism is upregulated. This initial analysis will allow the subsequent identification of novel intrinsic antimicrobial resistance determinants.

Development requires the expression of master regulatory genes necessary to specify a cell lineage. Equally significant is the stable and heritable silencing of master regulators that would specify alternative lineages. This regulated gene silencing is carried out by Polycomb group (PcG) proteins, which must be correctly recruited only to the subset of their target loci that requires lineage-specific silencing. A recent study by Erceg and colleagues (pp. 590–602) expands on a key aspect of that targeting: The same DNA elements that recruit PcG complexes to a repressed locus also encode transcriptional enhancers that function in different lineages where that locus must be expressed. Thus, PcG targeting elements overlap with enhancers.

This paper proposes and compares two nonlinear time-domain models of self-excited thermoacoustic oscillations of laminar premixed flames. Both models are hybrid formulations, where the flame and its immediate vicinity are resolved with a reactive flow simulation, while the acoustic field is modeled with a low-order model that is coupled to the reactive flow simulation. Firstly, a flame model based on the fully compressible Navier–Stokes equations is investigated. In this case, the flame simulation is coupled to the low-order model via the characteristic wave amplitudes at the inlet boundary. Secondly, the flame is resolved with a low Mach number reactive flow simulation. In order to include two-way thermoacoustic feedback, this flame model is coupled with an acoustic network model via the global heat release rate and the fluctuation of the axial velocity at a reference position upstream of the flame. A bifurcation analysis using the plenum length as bifurcation parameter is conducted. Both models exhibit complex nonlinear oscillations and are in good agreement with each other. Therefore, we conclude that the coupling of a linear acoustic model and a nonlinear flame model via reference velocity and global heat release rate is sufficient to accurately capture thermoacoustic oscillations of the configuration investigated. This implies that the most important nonlinearities can be attributed to hydrodynamic effects and flame kinematics. Furthermore, the study corroborates that premixed flames respond predominantly to fluctuations of the upstream flow velocity.

Background. Epidemiological evidence on the association between ambient air pollution and brain tumor risk is sparse and inconsistent. Methods. In 12 cohorts from 6 European countries, individual estimates of annual mean air pollution levels at the baseline residence were estimated by standardized land-use regression models developed within the ESCAPE and TRANSPHORM projects: Particulate matter (PM) ≥2.5,≥10, and 2.5-10 FÊm in diameter (PM2.5, PM10, and PMcoarse), PM2.5 absorbance, nitrogen oxides (NO2 and NOx) and elemental composition of PM. We estimated cohort-specific associations of air pollutant concentrations and traffic intensity with total, malignant, and nonmalignant brain tumor, in separate Cox regression models, adjusting for risk factors, and pooled cohort-specific estimates using random-effects meta-analyses. Results. Of 282 194 subjects from 12 cohorts, 466 developed malignant brain tumors during 12 years of follow-up. Six of the cohorts also had data on nonmalignant brain tumor, where among 106 786 subjects, 366 developed brain tumor: 176 nonmalignant and 190 malignant. We found a positive, statistically nonsignificant association between malignant brain tumor and PM2.5 absorbance (hazard ratio and 95% CI: 1.67; 0.89.3.14 per 10.5/m3), and weak positive or null associations with the other pollutants. Hazard ratio for PM2.5 absorbance (1.01; 0.38.2.71 per 10-5/m3) and all other pollutants were lower for nonmalignant than for malignant brain tumors. Conclusion. We found suggestive evidence of an association between long-term exposure to PM2.5 absorbance indicating traffic-related air pollution and malignant brain tumors, and no association with overall or nonmalignant brain tumors. © 2018 The Author(s). Chemicals/CAS: nitric oxide, 10102-43-9; nitrogen dioxide, 10102-44-0

A study on the velocity sensitivity and intrinsic thermoacoustic stability of a laminar, premixed, Bunsen-type flame is carried out. Direct numerical simulation (DNS) of the flame, placed in an acoustically anechoic environment and subjected to broad-band, low-amplitude acoustic forcing, generates time series of fluctuating heat release rate, velocities and pressure. The time series data is post-processed with system identification to estimate the impulse response and transfer function of the flame. The associated frequency response is validated against experiment with good accuracy. DNS results obtained with acoustic excitation from the inlet or outlet boundary, respectively, confirm that the flame responds predominantly to perturbations of velocity. The stability of eigenmodes related to intrinsic thermoacoustic feedback is investigated with a network model. Both stable and unstable intrinsic thermoacoustic modes are predicted, depending on details of the configuration. The predicted modes are directly observed in direct numerical simulations, with good agreement in frequencies and stability.

In order to enable dynamic driving while increasing both safety and comfort, active suspension systems can minimize or completely eliminate roll movements in the vehicle body. Active electrical roll stabilization can provide high dynamics to compensate roll movement during cornering while rapidly compensating road irregularities. Whereas battery-stabilized 48 V systems provide sufficient power and speed to source the required highly dynamic current of existing roll stabilizers, such 48 V energy storages in addition to a standard 12 V battery increase weight and cost. We present a highly dynamic DC/DC converter to eliminate the 48 V battery. The bidirectional 12 V/48 V converter uses a mixed feed-forward/feed-back design to deal with both rapid 48 V load changes as well as fluctuations of the 12 V supply caused by typical 12 V loads and the generator. Latest wide-bandgap semiconductors in a multiphase topology enable the high required speed and efficiency.

Respiratory syncytial virus (RSV) is a leading cause of pneumonia and bronchiolitis in young children and the elderly. Therapeutic small molecules have been developed that bind the RSV F glycoprotein and inhibit membrane fusion, yet their binding sites and molecular mechanisms of action remain largely unknown. Here we show that these inhibitors bind to a three-fold-symmetric pocket within the central cavity of the metastable prefusion conformation of RSV F. Inhibitor binding stabilizes this conformation by tethering two regions that must undergo a structural rearrangement to facilitate membrane fusion. Inhibitor-escape mutations occur in residues that directly contact the inhibitors or are involved in the conformational rearrangements required to accommodate inhibitor binding. Resistant viruses do not propagate as well as wild-type RSV in vitro, indicating a fitness cost for inhibitor escape. Collectively, these findings provide new insight into class I viral fusion proteins and should facilitate development of optimal RSV fusion inhibitors.

The reaction of [Ru(arene)Cl(2)](2) (arene = benzene, p-cymene) with [X(2)W(22)O(74)(OH)(2)](12-) (X = Sb(III), Bi(III)) in buffer medium resulted in four organo-ruthenium supported heteropolytungstates, [Sb(2)W(20)O(70)(RuC(6)H(6))(2)](10-) (1), [Bi(2)W(20)O(70)(RuC(6)H(6))(2)](10-) (2), [Sb(2)W(20)O(70)(RuC(10)H(14))(2)](10-) (3), and [Bi(2)W(20)O(70)(RuC(10)H(14))(2)](10-) (4), which have been characterized in solution by multinuclear ((183)W, (13)C, (1)H) NMR, UV-vis spectroscopy, electrochemistry, and in the solid state by single-crystal X-ray diffraction, IR spectroscopy, thermogravimetric analysis, and elemental analysis. Polyanions 1, 2, and 4 crystallize in the triclinic system, space group P1 with the following unit cell parameters: K(5)Na(5)[Sb(2)W(20)O(70)(RuC(6)H(6))(2)] x 22 H(2)O (KNa-1), a = 12.1625(2) A, b = 13.1677(2) A, c = 16.0141(3) A, alpha = 78.9201(7) degrees, beta = 74.4442(8) degrees, gamma = 78.9019(8) degrees, and Z = 1; Cs(2)Na(8)[Bi(2)W(20)O(70)(RuC(6)H(6))(2)] x 30 H(2)O (CsNa-2), a = 11.6353(7) A, b = 13.3638(7) A, c = 16.7067(8) A, alpha = 79.568(2) degrees, beta = 71.103(2) degrees, gamma = 80.331(2) degrees, and Z = 1; Na(10)[Bi(2)W(20)O(70)(RuC(10)H(14))(2)].35H(2)O (Na-4), a = 15.7376(12) A, b = 15.9806(13) A, c = 24.2909(19) A, alpha = 92.109(4) degrees, beta = 101.354(4) degrees, gamma = 97.365(3) degrees, and Z = 2. Polyanions 1-4 consist of two (L)Ru(2+) (L = benzene or p-cymene) units linked to a [X(2)W(20)O(70)](14-) (X = Sb(III), Bi(III)) fragment via Ru-O(W) bonds resulting in an assembly with idealized C(2h) symmetry. Polyanions 1-4 are stable in solution as indicated by the expected (183)W, (13)C, and (1)H NMR spectra. The electrochemistry of 1-4 is described by considering the reduction and the oxidation processes. The nature of the arene in Ru(arene) has practically no influence on the formal potentials of the W-centers, which are more sensitive to the Sb or Bi hetero atoms. The results suggest that the respective Sb- and Bi derivatives have very different pK(a) values, with the reduced form of 1 being the most basic, thus permitting the observation of two well-developed voltammetric waves at pH 6. In contrast, the identity of the arene influences the oxidation processes, thus permitting to distinguish them. A strong electrocatalytic water oxidation peak is observed that is more positive than the one corresponding to the Ru(arene) oxidation process. Also a stepwise oxidation of the Ru(benzene) group could be observed at pH 3. The catalytic efficiency, on the other hand, of 1-4 toward the oxidation of n-hexadecane and p-xylene illustrated the effect of ruthenium substitution on the polyanion catalytic performance.

The increasing interest of neutron scattering scientists in multi-spectral moderators motivated the search for reliable moderator materials fulfilling these requirements. One very elegant approach is methane hydrate as a moderator material, a material, where a methane molecule is encaged by six water molecules on average, leads to a combination of the neutron scattering properties of solid methane and ice. In this contribution the investigation of methane hydrate at T = 20 K and the analysis of the resulting spectra will be discussed. The second part of the paper deals with the observed differences between simulation and experiment in the cold energy range. It will be shown that the stainless steel beam and its possibility to reflect cold neutrons—a neutron optical effect not included in MCNPX—is responsible for the disagreement.

Two episodes of accidental urea toxicosis are described in wild silver gulls (Larus novaehollandiae) following spillage of fertilizer grade urea at a commercial shipping facility near Perth, Western Australia. In both cases, urea spillage had been seen to contaminate freshwater wash-down pools on the wharves where ships were being unloaded and gulls were seen to be drinking and washing in the pools nearby the spillages. Affected birds were found moribund or dead. Necropsy and histopathological findings were non-specific and consisted of mild to moderate congestion of visceral organs and brain. Analysis of a water sample collected during Case 1 revealed a very high urea concentration of 4.124 mol/l (pH 5.5), and fluid from the proventriculus of two birds had urea concentrations of 382 and 308 mmol/l, respectively. Nine birds were examined during the second episode (Case 2) and, from heparinized heart blood samples collected (n = 5), the mean plasma urea (288 +/- 92.0 mmol/l), ammonia (43.9 +/- 34.2 mmol/l) and uric acid (7.45 +/- 1.99 mmol/l) concentrations were markedly elevated above the reference ranges for all bird species. Proventricular contents (n = 7) similarly contained high concentrations of urea (394 +/- 203 mmol/l) and ammonia (9.3 +/- 15 mmol/l). The probable mechanisms of urea and ammonia toxicity in these birds are discussed.

Two major protease activities were present in gut homogenates of the cladoceran crustacean Daphnia magna: (i) a trypsin activity that hydrolysed the synthetic substrate N-benzoyl- dl -arginine p-nitroanilide and was strongly inhibited by N-p-tosyl-lysine chloroketone (TLCK) and 4-(amidinophenyl)methanesulfonyl fluoride (APMSF) and not inhibited by chymostatin; and (ii) a chymotrypsin activity that hydrolysed synthetic chymotrypsin substrates containing more than one amino acid, did not hydrolyse N-benzoyl- l -tyrosine p-nitroanilide, and was strongly inhibited by chymostatin and not by TLCK and APMSF. Both activities had alkaline pH optima (pH 7–10), but were shown to be due to distinct types of proteases. These two enzyme activities accounted for 75–83% of the proteolytic activity of gut contents. Substrate SDS-polyacrylamide gel electrophoresis revealed nine different proteases ranging from 15 to 73 kDa.

In spectra obtained from foil-excited and laser-produced plasmas, we have identified 70 new lines as belonging to the spectra of fluorine-like scandium and vanadium ions, Sc XIII and V XV The new lines in the wavelength region from 70 to 600 Angstrom represent 2p(4)3s-3p, 3p-3d and 3d-4f transition arrays. The spectra have been interpreted with the aid of theoretical calculations, and the consistency of our derived 3s, 3p, 3d and 4f energy levels has been checked by means of isoelectronic comparisons.

The effects of acute (3 h), repeated acute (3 exposures each of 3 h) and chronic (72 h) normobaric hyperoxic exposure in budgerigars (Melopsittacus undulatus) were evaluated by monitoring the effects on pulmonary enzymic antioxidants, and indicators of lipid peroxidation. All durations of oxygen exposure resulted in significant respiratory alkalosis and elevated pulmonary and blood glutathione peroxidase concentrations. The concentrations of other pulmonary enzymic antioxidants including glutathione reductase and superoxide dismutase were not significantly altered by oxygen exposure. Pulmonary concentrations of the lipid peroxidation markers malonaldehyde and 4-hydroxyalkenal were not significantly elevated following oxygen exposure. Plasma concentrations of 8-epi isoprostane F(2alpha) were significantly elevated following both acute and repeated acute exposure. The results indicate that in budgerigars, both acute and chronic oxygen exposure can result in significant alteration in respiratory function and increased production of reactive oxygen species.

Concentrations of polycyclic aromatic hydrocarbons (PAH) and oxidised PAH (oxy-PAH) from outdoor air were determined. Size-fractionated aerosol samples were collected in the city of Munich (Germany). Twenty-four hour samples with six- and nine-stage Berner-type low-pressure impactors were collected between 1996 and 1998. Fluoranthene, pyrene, chrysene, benzo[b] flu oranthene, benzo[k]fluoranthene, benzo[a]pyrene and benzo[ghi]perylene were quantified by HPLC with fluorescence detection. The averaged sum of these PAH reached 1.24 ng m−3 (range: 0.68–1.85ngm−3) at the inner city site which was not directly influenced by any road nearby, whereas samples from two sites close to busy roads exhibited average PAH concentrations equal to 5.61 ngm−3 (range: 3.65#x02013;6.65ngm−3) and 5.74ngm−3 (range: 1.67–15.13ngm−3). The PAH concentration observed at the northern outskirts of Munich ranged from 0.15 to 9.45ngm−3 (average: 2.4ngm−3). Different distributions of the PAH in the investigated particle size fractions were observed. Close to the road (at about 1 m off), about 40% of the PAH were found in the particle fraction with diameters of 0.06-0.13 μm. Similar distributions were observed at the second sampling site located close to a road when winds blew directly from this road. When winds blew from other directions, higher percents of PAH were present on larger particles. A bigger accumulation of PAH on particles ranging from 0.26 to 0.9 μm was also observed at the outskirts. Since the lung dose of particle-associated compounds is influenced by the distribution of the compounds within the particle size range, the observed differences in the distribution of PAH have implications on human exposure.

Glycosylphosphatidylinositol-anchored proteins (GPI-APs) are a class of lipid anchored proteins expressed on the cell surface of eukaryotes. The potential interaction of GPI-APs with ordered lipid domains enriched in cholesterol and sphingolipids has been proposed to function in the intracellular transport of these lipid anchored proteins. Here, we examined the biological importance of two saturated fatty acids present in the phosphatidylinositol moiety of GPI-APs. These fatty acids are introduced by the action of lipid remodeling enzymes and required for the GPI-AP association within ordered lipid domains. We found that the fatty acid remodeling is not required for either efficient Golgi-to-plasma membrane transport or selective endocytosis via GPI-enriched early endosomal compartment (GEEC)/ clathrin-independent carrier (CLIC) pathway, whereas cholesterol depletion significantly affects both pathways independent of their fatty acid structure. Therefore, the mechanism of cholesterol dependence does not appear to be related to the interaction with ordered lipid domains mediated by two saturated fatty acids. Furthermore, cholesterol extraction drastically releases the unremodeled GPI-APs carrying an unsaturated fatty acid from the cell surface, but not remodeled GPI-APs carrying two saturated fatty acids. This underscores the essential role of lipid remodeling to ensure a stable membrane association of GPI-APs particularly under potential membrane lipid perturbation.

The relative sensitivity of conventional assays of liver function was evaluated in com- parison with galactose clearance, a test of liver function used in humans since the 1960s. Results of galactose clearance tests were compared with plasma enzyme concentrations and serum bile acid levels in clinically normal galahs (Eolophus roseicapillus; n = 8), after celiotomy (n = 4), and after 6% or 18% hepatectomy (n = 8, respectively). Clearance tests and biochemical analyses were performed within 2-4 hours of surgery and at 4 and 7 days after surgery. Celiotomy and 6% and 18% hepatectomy resulted in changes in alkaline phosphatase, aspartate aminotransferase, and al- anine aminotransferase concentrations that were consistent with muscle trauma. Celiotomy and 6% hepatectomy did not significantly alter the results of galactose clearance tests; however, 18% hep- atectomy resulted in significant reduction in galactose clearance and galactose clearance as a func- tion of body surface area (GEC-SA). Galactose single-point concentrations were not significantly elevated at any time during the experiments; however, single-point concentrations were strongly correlated with galactose clearance and GEC-SA values, especially at 80 minutes after galactose injection. Serum bile acid levels were not significantly elevated after celiotomy or partial hepatec- tomy. Measurement of galactose single-point concentrations has the potential to be a simple, sen- sitive method of screening for reduced hepatic function in birds. Galactose clearance and GEC-SA have the potential to be sensitive assays of hepatic functional mass, for use as a noninvasive method of monitoring hepatic function.

The tetrairon(III)-substituted polytungstates [Fe(4)(H(2)O)(10)(beta-XW(9)O(33))(2)](n-) (n = 6, X = As(III), Sb(III); n = 4, X = Se(IV), Te(IV)) were immobilized on (3-aminopropyl)triethoxysilane-modified SBA-15 and showed an excellent catalytic performance for solvent-free aerobic oxidation of long-chain n-alkanes using air as the oxidant under ambient conditions through a classical free-radical chain autoxidation mechanism.

Structural parameters and the magnetic structure of TbPtGa are determined from neutron powder diffraction performed in white beam time-of-flight technology. The crystallographic space group is Pnma with four formula units per cell and Tb, Pt and Ga at sites 4c(x, 1 4 , z) each. Refined lattice constants, atomic positional parameters and interatomic distances are presented. At 25 ± 1 K TbPtGa undergoes a magnetic phase transition into a collinear antiferromagnetic structure with propagation vector k=[0, 1 2 , 0] . Terbium magnetic moments of 7.4(1) μ B are oriented along the b axis.

To evaluate the health and nutritional status of 3 wild Australian psittacine species, plasma and hepatic mineral concentrations and plasma biochemical values were measured in wild-caught galahs (Eolophus roseicapilla), long-billed corellas (Cacatua tenuirostris), and sulphur-crested cockatoos (Cacatua galerita). No correlations were found between hepatic and plasma mineral levels. Mean plasma calcium (1.79 mmol/L [7.16 mg/dL]) and sodium (103 mmol/ L [103 mEq/L]) concentrations were lower, whereas mean total phosphorus (6.53 mmol/L [20.22 mg/dL]) and potassium (8.87 mmol/L [8.87 mEq/L]) concentrations were higher than values for captive counterparts. Plasma iron levels were higher than those reported for captive counterparts, with evidence of interspecific (sulphur-crested cockatoos, 109 micromol/L [609 microg/dL]; corellas, 57 micromol/L [318 microg/dL]; galahs, 90 micromol/L [503 microg/dL]) and temporal variation (galahs: May, 107 micromol/L [598 microg/dL]; July, 59 micromol/L [330 microg/dL]). Hepatic iron concentrations were as high as 1030 mg/kg. Interspecific variation was minimal in mean plasma selenium (11.8 micromol/L [929 microg/L]) and zinc (31.2 micromol/L [204 microg/dL]) concentrations. Plasma biochemical values varied significantly from reported reference ranges. Ranges for total protein, albumin, and bile acid concentrations were lower, whereas uric acid, glutamate dehydrogenase, amylase, and cholesterol concentrations were higher than those previously reported for these species, and interspecific variation was evident. Variation in measures of mineral status or plasma biochemical values between males and females were negligible. An evaluation of fecal microflora showed a distinct absence of gram-negative bacteria or budding yeast. Results of this study show that analyte values used to determine health and nutritional status of wild birds differ from those published for captive counterparts. Although analyte values appear to vary minimally by sex, distinct taxonomic and some temporal differences exist in values from wild birds of these 3 species.

The selective oxidation of alkanes as a green process remains a challenging task because partial oxidation is easier to achieve with sacrificial oxidants, such as hydrogen peroxide, alkyl hydroperoxides or iodosylbenzene, than with molecular oxygen or air. Here, we report on a heterogeneous catalyst for n-hexadecane oxidation comprised of the wheel shaped Cu20-polyoxotungstate [Cu20Cl(OH)24(H2O)12(P8W48O184)]25- anchored on 3-aminopropyltriethoxysilane (apts)-modified SBA-15. The catalysts were characterized by powder X-ray diffraction (XRD), N2-adsorption measurements and Fourier transform infrared reflectance (FT-IR) spectroscopy. The heterogeneous Cu20-polyanion system catalyzed the solvent-free aerobic oxidation of n-hexadecane to alcohols and ketones by using air as the oxidant under ambient conditions. The catalyst exhibits an exceptionally high turn over frequency (TOF) of 20,000 h(-1) at 150 degrees C and is resistant to poisoning by CS2. Moreover, it can be easily recovered and reused by filtration without loss of its catalytic activity. Possible homogeneous contributions also have been examined and eliminated. Thus, this system can use air as oxidant, which, in combination with its good overall performance and poison tolerance, raises the prospect of this type of heterogeneous catalyst for practical applications.

Values for galactose and indocyanine green (ICG) clearances, and plasma and serum biochemical markers of liver dysfunction were determined in normal chickens and following coeliotomy, and compared with birds after partial hepatectomy. Clearance tests, and serum and plasma biochemistry were performed 4h, and 4 and 7 days after surgery. Coeliotomy and manipulation of the liver did not delay clearance of either compound. Partial hepatectomy resulted in elevation of galactose single point concentrations but did not significantly alter galactose clearance (GEC) values. Clearance values of ICG were not significantly altered. Biochemical values were not significantly elevated in birds after a partial hepatectomy in comparison with birds after coeliotomy. Galactose single point concentrations have the potential to become a simple, relatively non-invasive method of screening for liver disease, with GEC tests having the potential to quantify the degree of loss of functional hepatic mass.

The aerial parts of Hoffmannia strigillosa afforded, in addition to known compounds, seven new diterpenes, five clerodanes, two ent -phyllocladanes (8,13-bis- epi - ent -kauranes) and two new monoterpenes. The structures were elucidated by high field NMR spectroscopy.

The two main saponins of commercially available extract of Primula sp. were isolated by HPLC. Their structures were elucidated by spectroscopic methods as already known primulasaponin (1) and the new 3-O-?[alpha-rhamnopyranosyl-(1-->2)-beta- galactopyranosyl-(1-->3)-[beta-xylopyranosyl-(1-->4)-beta-glucopyranosyl - (1-->2)]-beta-glucuronopyranosyl]?-protoprimulagenin A (2).

SANS anisotropies from SiO2 precipitates in Cz-silicon depend on the initial oxygen content and temperature. There is a particle-shape governed central peak and numerous weak intensities for larger Q-values. They originate from a correlation between the precipitates and disappear reversibly at temperatures below 100K. Model calculations do well resemble the observed intensity patterns.

The formation of silicon oxide precipitates from Czochralski grown silicon depends on the time and temperature of the heat treatment as well as on the initial content of interstitially dissolved oxygen. Samples containing between 5×1017 Oi/cm3 and 13×1017 Oi/cm3 have been heated at 750° C for 96 h. SiO2 precipitates of various shape and size have been obtained and investigated by means of small angle neutron scattering (SANS) in the Q-range 0.05 A−1

This communication presents four different assay systems for the determination of myeloperoxidase in body fluids. One is based on conventional chemiluminescence, two on luminescence-amplified enzyme measurement using either spiroadamantane-1,2-dioxetanes with alkaline phosphatase or luminol/peroxidase/4-iodophenol coupled with a peroxidase label. The assays covered the range 0-600 micrograms/l peroxidase. Established reference range for EDTA plasma from healthy volunteers gave an upper limit of 250 micrograms/l (95% confidence limits). Intra-assay coefficients of variation were less than 5% for all assays, as seen in compound precision profiles. Inter-assay variation was less than 10% throughout the whole concentration range. Kinetic curves for the light production were performed over a 2 hour period for the enhanced luminescence assays. Dynamic ranges of these assays were compared with the conventional colorimetric assay using 4-nitrophenyl phosphate--alkaline phosphatase. The assay was standardized using a commercially available myeloperoxidase preparation with defined enzymatic activity. The protein content was estimated and the laboratory standard compared and calibrated in mass units.

We have continued our investigations on magnetic excitations in the olivine-type silicates with neutron scattering measurements on Co 2 SiO 4 . The excitation spectra have been compared with classical spin-wave model calculations. As already reported for Fe 2 SiO 4 also the Co-compound shows a strong coupling between magnons and phonons. Further, we could confirm a magnetic pre-ordering above the Neel-temperature of 49 K.

In the first part of this work matrix cells were examined by [3H]TdR autoradiography in rat embryos from the twelfth to the eighteenth day of gestation. A time-table of the cell cycle during embryonic development was calculated from the generation time (Tc) and the duration of the DNA-synthetic phase (TS), which were determined by the labeling index and by a modified double-labeling technique. The results show that the generation time (Tc) lenghtens from the twelfth to the eighteenth day of gestation (11 h and 19 h respectively). There is a significant increase in TC between days 14 and 15. The mean DNA-synthetic phase (TS) remains fairly constant within the time studied, ranging from 6 to 8 h. The lengthening of TC results mainly from an increase of the pre-synaptic phase (G1). Calculations were made both for steady-state and exponential cell proliferations. These results are mean values based on the presumption that all cells are equally distributed throughout the cell cycle and that the entire cell population participates in the proliferating activity. In order to obtain more detailed information concerning the growth characteristics of the matrix cell population the second part of this work was performed, using continuous [3H]TdR infusions for 4, 6, 8, 10 and 14 h. It was shown that the matrix cell layer comprises at least two different cell populations with different generation times. Details of the calculations are discussed in the Appendix.

Die Iminonitrile (I), erhalten nach Literaturverfahren oder analogen angewandten Verfahren, cyclisieren in Gegenwart von LiOH oder, in einigen Fallen, von NEt3 zu den Titelverbindungen (II).

The effects of oxygen exposure on pulmonary and blood non-enzymic antioxidant concentrations was evaluated in budgerigars (Melopsittacus undulatus). Budgerigars were exposed to acute (3 h), repeated acute (3 exposures each of 3 h) or chronic (72 h) normobaric hyperoxic environments and the pulmonary and plasma concentrations of selected non-enzymic antioxidants, namely glutathione, uric acid, alpha- and gamma-tocopherol and carotenoids were assayed. With increasing duration of oxygen exposure, the ratio of oxidised to reduced glutathione was significantly increased, while the concentrations of uric acid, alpha- and gamma-tocopherol and carotenoids were significantly reduced, especially following chronic oxygen exposure. Following acute and repeated acute exposure, alteration in glutathione concentrations and reduction in alpha-tocopherol concentrations indicated oxygen stress. Following chronic exposure, depletion of non-enzymic antioxidants indicated exhaustion of these protective mechanisms and progression from oxygen stress to oxygen toxicity.