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A new approach for biomass liquefaction was developed and evaluated in a joint research project. Focus of the project, called FEBio@H2O, lies on a two-step hydrothermal conversion. Within step 1, the input biomass is converted employing a hydrothermal degradation without added catalyst or by homogeneous catalysis. Within step 2, the hydrogen accepting products of step 1, e.g., levulinic acid (LA) are upgraded by a heterogeneously catalyzed hydrogenation with hydrogen donor substances, e.g., formic acid (FA). As a result, components with an even lower oxygen content in comparison to step 1 products are formed; as an example, γ-valerolactone (GVL) can be named. Therefore, the products are more stable and contained less oxygen as requested for a possible application as liquid fuel. As a hydrothermal process, FEBio@H2O is especially suitable for highly water-containing feedstock. The evaluation involves hydrothermal conversion tests with model substances, degradation of real biomasses, transfer hydrogenation or hydrogenation with hydrogen donor of model substances and real products of step 1, catalyst selection and further development, investigation of the influence of reactor design, the experimental test of the whole process chain, and process assessment.

In this study, liquid chromatography–tandem mass spectrometry (LC–MSn; n = 2–3) has been used to characterize and distinguish chlorogenic acid lactones from cinnamoylshikimate esters. This is the first time when an LC–MSn method has been developed to distinguish between these two isomeric classes of compounds formed in particular in food processing from chlorogenic acids at elevated temperature through loss of water. The structures of regioisomeric chlorogenic acid lactones and shikimate esters have been assigned on the basis of LC–MSn patterns of fragmentation, relative hydrophobicity, and fragmentation analogy with the synthetic standards of dimethoxycinnamic, ferulic, and caffeic acid containing monoacyl chlorogenic acid lactones and shikimate esters. Copyright © 2011 John Wiley & Sons, Ltd.

The catalytic properties of highly dispersed, bacterial surface layer supported nanoscale platinum clusters immobilized at alumina particles are studied with respect to carbon monoxide oxidation. Compared to samples prepared from platinum impregnated alumina, the templated metal clusters are catalytically active at lower temperatures. The catalytic behaviour of the samples is discussed with respect to their cluster morphology studied by TEM.

Different vehicle manufacturers mount an air dam on the vehicle undercarriage just in front of the wheels. For better understanding of the noise generation mechanisms and flow induced vibrations directly at their source region, the acoustical effects in the interior of the vehicle will be correlated by the University of Applied Sciences Duesseldorf and BMW with the pressure fluctuations of the exterior of the vehicle. Steady state CFD calculations in the area of the rotating front wheel will be carried out for the positioning of the surface microphones and for a better understanding of the flow topology.

Die Staulippe befindet sich an Fahrzeugen unterschiedlicher Automobilhersteller am Unterboden jeweils vor den Radern. Ihre akustische Wirkung im Fahrzeuginnenraum wird im Rahmen einer Untersuchung der FH Dusseldorf und BMW mit Druckschwankungen an der Fahrzeugau:sBenseite korreliert, um den Ent stehungsmechanismus von Gerauschen und stromungsinduzierter Schwingungen bereits im Quellbereich besser zu verstehen. Fur die Positionie rung der Wandmikrofone und fur ein tieferes Verstandnis der Stromungstopografie werden stationare CFD-Rechnungen im Bereich des rotierenden Vorderrades durchgefuhrt.

AIM: A remodelling of the pancreatic cancer tumour microenvironment and extracellular matrix (ECM) has been implicated in the prognosis of PDAC. We investigated whether the aspartic protease cathepsin D contributes to proliferation, migration and fibrogenesis of pancreatic cancer cells and its expression affects the survival of pancreatic cancer patients. MATERIALS & METHODS: Mouse pancreatic stellate cells (PSC) were isolated by Nycodenz gradient. PSC and murine pancreatic cancer PD6606 cells were used for Western blotting and immunofluorescence staining. Cathepsin D activity was inhibited with pepstatin and its expression silenced with siRNA. TGFβ1 was measured using microplate sandwich ELISA and proliferation by standard MTT assay. Tumour tissue microarrays of 404 patients from the ESPAC-3 trial (all after PDAC-resection) were stained with anti-cathepsin D (C-20) antibody and patients with the highest quartile H-score (cut-off 22.35) were compared with those in the lowest quartile using Kaplan-Meier curves, log-rank tests, and Cox proportional hazards models. All statistical tests were two-sided. RESULTS: Inhibition of cathepsin D in ductal adenocarcinoma cells resulted in significantly reduced proliferation and migration. Cathepsin D expression increased in parallel with PSC trans-differentiation to myofibroblasts. Silencing (siRNA) or inhibiting cathepsin D decreased PSC proliferation by 20-30%. There was a time-dependent activation of latent TGF β1 and cathepsin D cleaved latent TGF β1, leading to its activation. Inhibition of cathepsin D decreased activated TGF β1. In 1824 tissue microarray cores from 382 patients (94.6%) median overall patients' survival was 23.85 months (95% CI 21.0-26.2). Median survival for patients in the highest quartile cathepsin D H-score was 21.2 months (95% CI 17.3-24.8) and in the lowest quartile 27.2 months (95% CI 24.1-31.2) χLR,1DF = 4.33; P = 0.0374. DISCUSSION: In pancreatic cancer, cathepsin D expression not only regulates fibrogenesis and stromal development but also ductal adenocarcinoma cell proliferation and migration. These mechanisms make cathepsin D a driver of pancreatic cancer growth and account for the poor prognosis of patients with high cathepsin D expression in PDAC.

Das Windgerausch spielt eine entscheidende Rolle beim Innengerauschkomfort. Bis jetzt wird durch Feinschliffmasnahmen das Windgerausch so optimiert, dass keine subjektiv wahrnehmbaren Storgerausche auf die Insassen wirken. Um in der Konzeptgestaltung eines Fahrzeugs die entscheidenden Komponenten auszulegen, ist der erweiterte Einsatz von neuen Versuchs- und Simulationsmethoden erforderlich. Fur den Akustikwindkanal der BMW Group wurde dazu in Zusammenarbeit mit Horiba ATS eine Modulwaage entwickelt und installiert, die fur die Losung von aeroakustischen Aufgaben vollig neue Moglichkeiten eroffnet.

Wind noise plays a deciding role today in reaching a high level of interior comfort within premium vehicles. Until now, wind noise was optimized using small incremental changes in such a manner that no subjectively measured noise sources had a large influence on the passengers. In the concept phase of the development of a vehicle, while the layout of the vehicle geometry is being developed, the incorporation of new testing and simulation techniques is essential. Above all the correlation between flow effects and noise must be determined. The BMW Group acoustic wind tunnel was used in cooperation with the firm Horiba ATS to develop and install a balance module that opens entirely new possibilities to solve for aeroacoustic effects.

Experimental investigations of flow-induced noise and the resulting interior acoustics are presented. The turbulent flow field next to the side window results in sound sources and, consequently, in the radiation of sound. The combination of these sound pressure fluctuations and the hydrodynamic wall-pressure fluctuations excites the side window and results in radiation of noise into the passenger cabin. To investigate these physical effects, a simplified model of an automobile was set up. The whole model is insulated acoustically in such a way that noise radiation to the interior is limited to the side window. To modify the flow around the model, a square bar at the a-pillar or a side mirror model was mounted. A microphone at the position of the driver’s ear detected the sound radiation to the interior. In order to quantify excitation of the side window, phase-resolved laser-scanning vibrometer measurements were performed. Furthermore, unsteady pressure measurements were carried out at the window surface. The investigations led to a better understanding of the physical mechanism of flow-induced sound generation and also the contribution of sound sources to the interior acoustics.

Experimental investigations of the flow-induced noise and the resulting interior acoustics are presented. The turbulent flow field next to the side window of a passenger car results in sound sources and, consequently, in the radiation of sound. The combination of these sound pressure fluctuations and the hydrodynamic wall-pressure fluctuations excites the side window and results in radiation of noise into the passenger cabin. To investigate these physical effects, a simplified model of an automobile was set up. The whole model is insulated acoustically in such a way that noise radiation to the interior is limited to the driver’s door. The overflown outer geometry is identical to the SAE (Society of Automotive Engineers)-body. To modify the flow around the model, an obstacle at different positions at the a-pillar and various side mirrors were mounted. Oil-flow visualization was applied to gain an impression of the complex flow structures in the wake of the a-pillar as well as the side mirror model. A microphone at the position of the driver’s ear detected the sound radiation to the interior. Furthermore, unsteady pressure measurements were carried out at the window surface to calculate wavenumber-frequency spectra of the pressure fluctuations. In order to quantify the application of energy to the side window, phase-resolved laser-scanning vibrometer measurements were performed. Based on these vibration measurements, the radiation of sound to the microphone position was computed employing a finite-element acoustics solver. The investigations provide a better understanding of the influence of different parameters on the sound radiation as well as the contribution of sound sources to the interior acoustics. In addition, the results act as a basis of comparison for numerical simulations.

An Escherichia coli mutant described by Noguchi et al. [Noguchi, S., et al. (1982) J. Biol. Chem. 275, 6544-6550] contains tRNA lacking the hypermodified wobble nucleoside queuosine (Q) due to an inactive tRNA-guanine transglycosylase (TGT). TGT catalyzes the posttranscriptional base exchange of the Q precursor preQ1 with the genetically encoded guanine in tRNA(Asp,Asn,His,Tyr). The mutant tgt gene was cloned and sequenced; it contained a single point mutation resulting in the change of serine 90 to phenylalanine. Overexpression of the mutant gene yielded TGT(S90F) that showed a reduced solubility and did not purify in the same fashion as the wild-type enzyme. TGT(S90F) has no detectable enzymic activity. To determine whether serine 90 performs a catalytic role in the TGT reaction or whether the loss of activity was caused solely by a conformational change of the enzyme, we used site-specific mutagenesis to construct serine-to-alanine (S90A) and serine-to-cysteine (S90C) mutants. Both S90A and S90C mutants were purified in a manner identical to that used for the wild-type enzyme. SDS-PAGE of dimethyl suberimidate-cross-linked mutants showed a pattern identical to that of the wild-type TGT, indicative of a trimeric quaternary structure. Native PAGE of wild-type and mutant TGTs in the absence and presence of substrate tRNA exhibited band shifts indicating that both mutants retain the ability to bind tRNA.(ABSTRACT TRUNCATED AT 250 WORDS)

In this study, liquid chromatography-tandem mass spectrometry (LC-MS(n); n = 2-3) has been used to characterize and distinguish chlorogenic acid lactones from cinnamoylshikimate esters. This is the first time when an LC-MS(n) method has been developed to distinguish between these two isomeric classes of compounds formed in particular in food processing from chlorogenic acids at elevated temperature through loss of water. The structures of regioisomeric chlorogenic acid lactones and shikimate esters have been assigned on the basis of LC-MS(n) patterns of fragmentation, relative hydrophobicity, and fragmentation analogy with the synthetic standards of dimethoxycinnamic, ferulic, and caffeic acid containing monoacyl chlorogenic acid lactones and shikimate esters.

Fifteen novel amiloride analogues were synthesized and their diuretic properties compared to amiloride and triamterene in white wistar rats. Whereas none of the 6-substituted derivatives exhibited significant natriuretic and antikaliuretic effects, five of the compounds modified in the 2-position were found equal or better than standards. The results are discussed with respect to chemical structure and physicochemical properties. Darstellung und diuretische Eigenschaften neuer Amiloridanaloga Es wurden funfzehn neue Amiloridanaloga dargestellt und ihre diuretischen Eigenschaften an White Whistar-Ratten mit denen von Amilorid und Triamteren verglichen. Wahrend keines der 6-substituierten Derivate signifikante natriuretische und antikaliuretische Wirkung zeigte, erwiesen sich funf der in Position 2 modifizierten Verbindungen als gleich gut oder besser wirksam als die Referenzsubstanzen. Die Ergebnisse werden im Hinblick auf die chemische Struktur und physikochemischen Eigenschaften diskutiert.

Fifteen novel amiloride analogues were synthesized and their diuretic properties compared to amiloride and triamterene in white wistar rats. Whereas none of the 6-substituted derivatives exhibited significant natriuretic and antikaliuretic effects, five of the compounds modified in the 2-position were found equal or better than standards. The results are discussed with respect to chemical structure and physicochemical properties. Darstellung und diuretische Eigenschaften neuer Amiloridanaloga Es wurden funfzehn neue Amiloridanaloga dargestellt und ihre diuretischen Eigenschaften an White Whistar-Ratten mit denen von Amilorid und Triamteren verglichen. Wahrend keines der 6-substituierten Derivate signifikante natriuretische und antikaliuretische Wirkung zeigte, erwiesen sich funf der in Position 2 modifizierten Verbindungen als gleich gut oder besser wirksam als die Referenzsubstanzen. Die Ergebnisse werden im Hinblick auf die chemische Struktur und physikochemischen Eigenschaften diskutiert.

A series of para-substituted triamterene derivatives (Table 1) were evaluated for their antiarrhythmic properties in vitro. Pharmacological evaluation of the compounds and some class-I- (quinidine, lidocaine, and propafenone) as well as class-III-antiarrhythmic drugs (±)-sotalol and amiodarone was carried out by measuring the functional refractory period (FRP), the maximal driving frequency (MDF) and the force of myocardial contractions (FC) of electrically stimulated guinea pig atria. The increase in FRP and the decrease in MDF was most pronounced with the class-I-antiarrhythmic drugs, but these compounds showed the typical negative inotropic effects, too. For the class-III-antiarrhythmics only a weak influence on FRP and MDF could be demonstrated, while FC was not altered in the presence of (±)-sotalol and amiodarone. Neutral substituted triamterenes like compounds 2—5 as well as most of the benzyltriamterene derivatives showed similar or stronger effects on FRP and MDF as (±)-sotalol and amiodarone. With the exception of 4 and 5, these effects were combined with an increase of FC. Compounds 6 and 7, well known potent diuretics, showed no influence to FRP, MDF and FC. Therefore, we conclude different mechanisms for the antikaliuretic and cardiac activity. In-vitro-Prufung von Triamterenderivaten auf antiarrhythmische Eigenschaften Es wurde eine Reihe von para-substituierten Triamterenderivaten (Tabelle 1) auf ihre antiarrhythmischen Eigenschaften untersucht. Die pharmakologische Prufung dieser Verbindungen und einiger Klasse-I- (Chinidin, Lidocain und Propafenon) und Klasse-III-Antiarrhythmika ((±)-Sotalol und Amiodaron) erfolgte durch Messung der funktionellen Refraktarzeit (FRP), der maximalen Treibfrequenz (MDF) und der Kontraktionskraft (FC) am elektrisch stimulierten Meerschweinchenvorhof. Der Anstieg von FRP und die Abnahme von MDF waren am deutlichsten bei den Klasse-I-Antiarrhythmika ausgepragt, aber diese Verbindungen zeigten auch den typischen negativ inotropen Effekt. Fur die Klasse-III-Antiarrhythmika konnte nur ein schwacher Einflus auf FRP und MDF nachgewiesen werden, wahrend FC in Gegenwart von (±)-Sotalol und Amiodaron nicht verandert wurde. Sowohl neutral substituierte Triamterenderivate wie die Substanzen 2—5 als auch Benzyltriamterenderivate zeigten ahnliche oder grosere Effekte auf FRP und MDF als (±)-Sotalol und Amiodaron. Mit Ausnahme von 4 und 5 waren diese Effekte mit einer positiv inotropen Wirkung verbunden. Die als potente Diuretika bekannten Triamterenderivate 6 und 7 zeigten in den Untersuchungen keinen Einflus auf FRP, MDF und FC. Daraus kann auf einen unterschiedlichen Mechanismus fur die antikaliuretische und kardiale Aktivitat geschlossen werden.

This paper is the first of a two-paper series that describes the experimental portion of a long-term, ongoing investigation - carried out by a consortium of the German automotive manufacturers Audi, BMW, Daimler, Porsche and Volkswagen - of the feasibility of predicting buffeting phenomena by means of computational fluid dynamics (CFD). The numerical simulations carried out as part of the study are reported on in the second paper of the series. Sunroof and side-window buffeting is a common phenomenon in passenger cars, and can cause considerable discomfort to the passengers due to the high sound-pressure levels (SPL) that are generated. The general physical mechanism, whereby an unsteady shear layer in the sunroof or window opening induces an acoustic resonance in the passenger compartment, is well-understood. However, experience has shown that making a priori predictions about the tendency of a given configuration to experience buffeting - essential in the early stages of the vehicle design process - with the required degree of reliability and accuracy is not possible. In the vehicle development process, pragmatic design solutions for suppressing buffeting at various wind speeds and geometric configurations are found experimentally. Previous work carried out by members of the consortium has shown that clearly identifying and isolating the individual factors that influence buffeting in real vehicles is very diffcult. They range from the geometry of the sunroof or side window, including small geometric details of the surrounding vehicle parts, to the quality of the oncoming flow, to the arrangement of the internal volume of the vehicle. Moreover, it has been found that the interaction of the fluid flow with the vehicle structure has a particularly large influence on buffeting behaviour and makes the analysis of the individual physical phenomena that contribute to the overall effect very diffcult. In order carry out a systematic analysis of these issues, the consortium devised a long-term project in which the first step, presented in this two-part publication, isolates and investigates only the issues related to fluid dynamics and acoustics, and ensures that the other aforementioned factors influencing buffeting play no role. Rigorous studies of this type which are also directly relevant to vehicle design are not found in the present literature. Only sunroof buffeting was considered in the present study, as the physical mechanism is essentially identical to that of side-window buffeting.

Wichtige Eigenschaften und Prozesse des Bodens werden durch dessen Humusausstattung beeinflusst. Kenntnisse uber den Humusstatus eines Bodens sind daher eine wichtige Voraussetzung, um z.B. Stoffdynamik und Gefahrdungspotentiale fundiert einschatzen zu konnen. Basierend auf dem umfangreichen Datenbestand des Bayerischen Landesamtes fur Umwelt, werden die typischen Humusgehalte und Humusvorrate fur Boden des Oberpfalzer und Bayerischen Waldes zusammengestellt. Ihre Bedeutung fur bodenkundliche und umweltrelevante Fragestellungen wird aufgezeigt. Wie die Auswertung zeigt, geht mit dem zunehmend kuhlfeuchten Klima der Mittelgebirgslagen ein deutlicher Anstieg der bodenburtigen Humusgehalte bzw. Humusvorrate einher. Dies trifft insbesondere fur den Mineralboden zu, wo oberhalb 600 m NN mehr abgestorbene organische Substanz gespeichert wird als in der Humusauflage. Die Gesamthumusvorrate variieren in Abhangigkeit von der Hohenlage zwischen ca. 12 und 40 kg* m−2, und sind damit als mittel bis sehr hoch einzustufen. Die hochsten Humusmengen entfallen auf die Hohenstufe zwischen 900 und 1200 m NN, wo relativ grundige, intensiv durchwurzelte Lockerbraunerden dominieren. Die etwas niedrigeren Gesamthumusvorrate der obersten Hohenstufe (> 1200 m NN) werden durch einen oberflachennah einsetzenden, stark verfestigten C-Horizont erklart, der die Durchwurzelung dieser Standorte auf die obersten 3–5 Dezimeter beschrankt. Die dennoch relativ hohen Humusvorrate dieses teilweise betonartig verfestigten Untergrunds (ca. 5 kg* m−2) beruhen wohl auf Einwaschungsprozessen. Die besonders machtige Humusauflage oberhalb 1200 m NN ist wahrscheinlich nicht nur klimatisch bedingt, sondern auch durch die schwer zersetzbare Streu der dort dominierenden Fichtenwaldgesellschaft erklarbar. Die hohen Humusvorrate in den Waldboden der ostbayerischen Mittelgebirge lassen bei einer Klimaerwarmung die Freisetzung betrachtlicher Mengen an C in Form von CO2 erwarten. Gleichzeitig durfte ein solcher Humusabbau insbesondere in den Gipfel- und Kammregionen zu einer deutlichen Verschlechterung der Nahrstoff- und Wasserversorgung fuhren.

Carotenoids and carotenoid-derived products were identified in green coffee beans of different origins. After extraction with acetone, the carotenoids, lutein and zeaxanthin, were identified by HPLC-Diode Array Detection. Glycosidically bound ionols were identified as carotenoid-derived products which are known to be formed by oxidative degradation of lutein and zeaxathin [1]. These glycosides were analysed by absorption on XAD-1180 resin followed by enzymatic hydrolysis of the eluted extract with β-glucosidase, and by GC-MS analysis of the released aglycones [2]. The impact of carotenoids on aroma formation was investigated by using a model roasting system. For this purpose, green coffee beans were depleted of their naturally occurring potential aroma precursors, and subsequently enriched with β-carotene, a carotenoid similar in structure to lutein and zeaxanthin. Under coffee roasting conditions, β-carotene yielded the aroma compound, β-ionone, as its major degradation product [3]. Furthermore, the importance of 3-oxo-α-ionol as an aroma precursor was investigated in the model system.

Im 2. Teil der Arbeit wurde eingehend die Relevanz des dieser Arbeit zu Grunde liegenden Problems, der Qualitatsbeurteilung von Dienstleistungen, erortert. Dabei konnte sowohl die praktische, handlungsorientierte Relevanz aufgezeigt werden als auch die theoretische Relevanz fur die Marketingwissenschaft. Beide Facetten der Relevanz auserten sich in einer Vielzahl nach wie vor bestehender Forschungsdefizite.

Eine Illustration der enormen Bedeutung von Dienstleistungen in der Realitat soll dem Leser einen Beurteilungsmasstab dafur liefern, inwiefern ein Ungleichgewicht zwischen der praktischen Relevanz des Problems der Dienstleistungsqualitat und dem Erkenntnisstand in der Marketingwissenschaft besteht. Grundlage zur Analyse der okonomischen Bedeutung einzelner Wirtschaftsbereiche und somit auch der Dienstleistungen bilden die volkswirtschaftlichen Gesamtrechnungen (VGR).77 Entsprechend der Systematik der Wirtschaftszweige werden die einzelnen wirtschaftlichen Institutionen zu Wirtschaftsbereichen zusammengefasst. Dabei wird nach dem Schwerpunktprinzip vorgegangen, was bedeutet, dass Unternehmen nach dem Schwerpunkt ihrer Aktivitaten zu bestimmten Bereichen zugeordnet werden. Die daraus resultierende institutionelle Gliederung der Unternehmen beruht auf der uberwiegend ausgeubten Tatigkeit einer einen Wirtschaftsbereich definierenden Aktivitat.78 Zur Messung der Aktivitat dienen Wertschopfungs-, Umsatz- oder Beschaftigtenanteile. In der VGR werden auf dieser Basis derzeit 58 unterschiedliche Wirtschaftsbereiche unterschieden, die wiederum unter den Oberbegriffen Land- und Forstwirtschaft, Fischerei, Produzierendes Gewerbe, Handel, Verkehr und Nachrichtenubertragung, Dienstleistungsunternehmen, Staat, Private Haushalte und Organisationen ohne Erwerbscharakter zusammengefasst sind.79 Die erste Gruppe wird haufig auch als primarer Sektor (Urproduktion) bezeichnet, das produzierende Gewerbe als sekundarer Sektor sowie die ubrigen Gruppen dem tertiaren Sektor zugeordnet.80 Auf Basis dieser Gliederung kann die wirtschaftliche Entwicklung des tertiaren Sektors naher betrachtet werden.

Die vorliegende Arbeit hatte das Ziel, einen Beitrag zu einer theoriegeleiteten Konzeptualisie-rung und Operationalisierung der Dienstleistungsqualitat zu leisten. Ausgangspunkt war eine wissenschaftstheoretische Standortbestimmung, die sich an der realtheoretischen Triade von Problem, Theorie und Empirie orientierte und eine ausgewogene Balance dieser Elemente forderte. Hieran orientierten sich auch die „Architektur“ des Untersuchungsaufbaus und die Formulierung der Forschungsfragen. In diesem Sinne wird mit der zusammenfassenden Beurteilung der Ergebnisse dieser Arbeit zum Abschluss das vierte Element der Realtheorie, das realtheoretische Wissen, also der Erkenntniszuwachs behandelt. Dementsprechend orientiert sich die Zusammenfassung der Arbeit an den in der Einfuhrung vorgestellten Forschungsfragen und den im Laufe der Untersuchung entwickelten Antworten. Besonderes Augenmerk wird dabei auf die Implikationen fur das Marketing-Management gelegt.

In this work, the draft European Standard prEN 15768 “The GC-MS identification of water leachable organic substances from materials in contact with water intended for human consumption” was applied to test 17 different commonly used plastic pipes for domestic plumbing systems for the migration of unexpected substances into drinking water. The tested pipes were made from 8 different plastic materials. Substances detected in the migration waters from the different pipe materials at concentrations exceeding 2 μg l−1 are reported. More than 60% of them could be identified by library search with the NIST mass spectral database. The migrated substances found and identified are discussed concerning their concentration trends with increasing time of testing. A significant number of substances identified were degradation products of antioxidants that are used as additives for the plastic materials. Possible degradation pathways for important antioxidants leading to frequently identified substances like 2,4-di-tert-butylphenol, 3-(3,5-di-tert-butyl-4-hydroxy-phenyl) propanoic acid, 7,9-di-tert-butyl-1-oxaspiro(4,5)deca-6,9-diene-2,8-dione, 3,5-di-tert-butyl-4-hydroxybenzaldehyde, and 2,6-di-tert-butyl-p-benzoquinone are proposed and discussed. As a conclusion, this study showed a good performance of the preliminary standard in practice.

Triamterene and several triamterene derivatives (Table 1) were tested for antiarrhythmic activity in the coronary artery ligated and reperfused (CAL-R) rat. The class-III antiarrhythmic drugs (±)-sotalol and amiodarone, the class-I antiarrhythmics lidocaine and quinidine as well as the potassium sparing diuretic amilorid were used as reference drugs. Triamterene at the highest dose (30 μmol/kg) revealed a 100% protection against ventricular fibrillation (VF), whereas at 10 μmol/kg no antiarrhythmic activity for triamterene could be found. For compound 4 (10 μmol/kg) a 75% protection against VF could be demonstrated, while 2, 3, and 5 revealed only a 25% protection. Compared to the reference drugs, triamterene and the derivatives 2–5 are more potent than (±)-sotalol, but less potent than lidocaine, quinidine and amiodarone. For amiloride as well as for the potent potassium retaining triamterene derivative 6 no antiarrhythmic activity could be shown. Therefore, we conclude different mechanisms responsible for the potassium sparing and antiarrhythmic properties of triamterene and its derivatives. Antiarrhythmische Eigenschaften von Triamteren-Derivaten am Modell der koronarligierten und reperfundierten Ratte Triamteren und verschiedene Triamterenderivate (Tab. 1) wurden in dem Modell der koronarligierten und reperfundierten Ratte auf antiarrhythmische Eigenschaften untersucht. Als Referenzsubstanzen dienten die Klasse-III-Antiarrhythmika (±)-Sotalol und Amiodaron, die Klasse-I-Antianrrythmika Lidocain und Chinidin und aus der Gruppe der kaliumsparenden Diuretika Amilorid. Triamteren zeigte bei der hochsten getesteten Dosis von 30 μmol/kg einen vollkommenen Schutz vor ventrikularer Fibrillation (VF), wahrend bei 10 μmol/kg keine antiarrhythmische Wirkung mehr nachweisbar war. Triamterenderivat 4 (10 μmol/kg) zeigte einen 75 proz. Schutz gegen VF, wahrend 2, 3 und 5 einen nur 25 proz. Schutz entwickelten. Im Vergleich zu den Referenzsubstanzen waren Triamteren und die Derivate 2–5 in diesem Modell wirksamer als (±)-Sotalol, jedoch weniger wirksam als Lidocain, Chinidin und Amiodaron. Sowohl fur Amilorid als auch fur das antikaliuretisch hochwirksame Triamterenderivat 6 konnte keine antiarrhythmische Aktivitat festgestellt werden. Daraus kann auf unterschiedliche Mechanismen der antiarrhythmischen Wirkung am Herzen und des antikaliuretischen Effekts an der Niere geschlossen werden.

The volatile compounds formed during autoxidation of linoleic acid and methyl linoleate at 22–24 °C were analysed by high resolution gas chromatography and eluate sniffing. The application of this technique to stepwise diluted extracts of the volatile compounds allowed the determination of a new parameter, theD-value, which reveals the most intense flavour compounds of an extract.

The volatile compounds formed during autoxidation of methyl linolenate (MLe) at 22–24°C were analyzed by a technique which reveals the flavor compounds having the highest flavor units (ratio of the concentration to the odor treshold). After a reaction time of 48 hr, when ca. 20 mol percent of the MLe had been converted into hydroperoxides,trans, cis-2,6-nonadienal followed by 1,cis-5-octadien-3-one,rans,cis-3-5-octadien-2-one andcis-3-hexenal showed the highest flavor units. After 102 hr 1,cis-5-octadien-3-one was by far the most important odor compound, followed bycis-3-hexenal andtrans,cis-2,6-nonadienal.

The FhuA protein in the outer membrane of Escherichia coli serves as a multifunctional receptor for the phages T5, T1, phi 80, for colicin M, for ferrichrome (Fe3+-siderophore) and for the structurally related antibiotic, albomycin. To determine structural domains required for these receptor functions and for export, a fusion protein between FhuA and Iut (receptor for Fe3+-aerobactin and cloacin DF13) was constructed. In the FhuA'-'Iut hybrid protein, 24 amino acids of FhuA were replaced by 19 amino acids, 18 of which were from Iut. The number of plaque forming units of phage T5 and T1 on cells expressing FhuA'-'Iut was nearly as high as on cells expressing plasmid-encoded wild-type FhuA. However, 10(7)-fold higher concentrations of phage phi 80 and 10(3) times more colicin M were required to obtain a zone of growth inhibition. Truncated FhuA' proteins in which the last 24 amino acids at the carboxy-terminus were replaced by 16 (FhuA'2) or 3 (FhuA'T) amino acids could hardly be detected on polyacrylamide electrophoretograms of outer membrane proteins, due to proteolytic degradation. Sensitivity of cells expressing FhuA'2 to phage T5 and T1 was reduced by several orders of magnitude and sensitivity to phage phi 80 and colicin M was totally abolished. In contrast, cells expressing FhuA'T were nearly as sensitive to pahge T5, T1, and phi 80 and to colicin M as cells containing FhuA'-'Iut. None of the constructs could grow on ferrichrome as sole iron source and none was sensitive to albomycin.(ABSTRACT TRUNCATED AT 250 WORDS)