Search

Background: A murine in vitro model of the allergic type I reaction was set up to determine the biologic activity of extracts without involvement of human beings. It is based on β-hexosaminidase release from passively sensitized RBL cells after allergen challenge. The intended application of this RBL cell assay in the field of quality control of allergenic extracts requires its comparison with established methods. Methods: The activity of five standardized birch-pollen prick test solutions was determined in parallel by RBL assay, direct IgE binding, IgE-binding inhibition, major allergen content, histamine-release assay, and skin testing. Results: The RBL cell-release assay corresponded well to other methods if a reagin raised against natural birch-pollen extract was used for passive sensitization. However, in the case of a reagin against recombinant Bet v 1, only a decreased activity was observed, presumably because a reduced number of epitopes were recognized by the monospecific reagin. In contrast to standardized birch-pollen extracts, nonstandardized apple extracts showed poor activity in all assays. Conclusions: This murine model might be a useful tool in the quality control of allergenic extracts. It combines properties of assays based on standardized antisera and of assays that consider IgE cross-linking properties.

This paper presents the machine description language LISA for the generation of bit- and cycle-accurate models of DSP processors. Based on a behavioral operation description, the architectural details and pipeline operations of modern DSP processors can be covered. Beyond the behavioral model, LISA descriptions include other architecture-related information like the instruction set. The information provided by LISA models enables automatic generation of simulators and assemblers which are essential elements of DSP software development environments. In order to proof the applicability of our approach, a realized model of the Texas Instruments TMS320C6201 DSP is presented and derived LISA code examples are given.

Lange Zeit lag der Schwerpunkt der judischen Bildungs- und Schulgeschichtsforschung auf der Rekonstruktion der Schulerziehung der Jungen. Aus dieser Perspektive wurde das liberale Judentum in der Kaiserzeit und in der Weimarer Republik als monolithischer Block in den Zusammenhang mit volliger Assimilation und Auflosung in die christliche Mehrheitskultur gebracht. Eine unreflektierte Gleichsetzung der Bildungsgange judisch-liberaler Kinder mit denen christlicher Kinder fuhrt jedoch zu unzulassigen Verallgemeinerungen. Zwar besuchten die judisch-liberalen Jungen tatsachlich nichtjudische Schulen, die auch die Eltern der christlichen hoheren Kreise Hamburgs fur ihre Sohne wahlten, aber die judisch-liberalen Madchen gingen dagegen oftmals zu sogenannten privaten Simultanschulen mit judischer Schulleitung.

The Reference Model for Open Distributed Processing (RM-ODP) [5] describes an architecture for the design of distributed services where the basic idea is to split the design concerns into several viewpoints. This is in order to overcome the immense complexity of today’s distributed systems by structuring the design process.

The TINA architecture specifications are well-known and have been available for many years. Experiences have been gathered with prototypical implementations of the TINA architecture or parts of it. These implementations have shown the benefits of the generic concept of TINA for surrounding distributed telecommunication services. Most of the implementations use new object-oriented implementation languages like C++ or Java and communication architectures like CORBA. However, up to now the question of the performance and satiability of TINA-conforming implementations, i.e., their eligibility for real applications with thousands of simultaneously acting users, still remains. This paper reports performance test results made with the TINA platform implementation at GMD FOKUS, which is based on C++, CORBA and Windows NT. The tests concentrate on the access session part of the service architecture (including subscription). The paper discusses the basic concepts of a flexible performance test architecture for distributed systems based on CORBA technology. Concrete performance test results are given, analysed and evaluated.

Publisher Summary Aged distilled spirits constitute a complex mixture of some hundreds of flavor compounds in an ethanol-water matrix. These flavor compounds, or congeners, originate from the original raw materials and the subsequent processes of mashing, fermentation, distillation and ageing, which together produce the final product. Complex inter-distillate reactions between congeners are also an important part of the flavor scenario, and this is particularly important during the ageing phase in oak barrels. There are many different approaches for the determination of abundant and trace congeners in distilled spirits. In many cases the apparatus and techniques are unique to the particular group or laboratory, and it can be difficult for other workers to reproduce the exact scheme adopted. This chapter also discusses some procedures favored by one of the present authors (K MacN), but a difference is that, they are rooted as much as possible in a dialogue with a specialist instrument manufacturer, and are therefore based on commercially available systems. Finally, much of the discussion and many of the examples centre around whiskey, but the methods and technology should be applicable to all distilled spirits.

This paper considers conformance testing of TINA service components in the realm of the ITU-T conformance testing methodology, which provides the only standardized, well accepted and widely used test methodology and test notation TTCN. It discusses the use of TTCN for testing computational objects of service components and proposes an implementation approach to derive executable tests from TTCN, which can be executed on any CORBA compliant ORB (with minor efforts for ORB specific adaptation) to check the functional correctness of deployed service components in distributed object environments. The TTCN/CORBA gateway is a general approach for testing distributed systems. TINA is taken as an example in this paper only. The work presented has been partially supported by the EC ACTS project TOSCA-TINA Open Service Creation Architecture, AC237.

International audience; We report on investigations of the excitonic quantum efficiency in GaN in dependence of different buffer layer thicknesses and residual oxygen content in the crystal. The quantum efficiency of the free excitons rises with increasing buffer layer thickness and decreasing residual oxygen content. The influence of oxygen on the quantum efficiency is stronger than that of the buffer layer thickness. In general, the observed quantum efficiencies are below 20% indicating the strong impact of nonradiative relaxation and recombination processes in the excitonic range.

Background: The determination of the biologic activity of allergenic extracts in human beings is limited for ethical and practical reasons. The establishment of a simplified in vitro model, which mimics a main event of the type I reaction, should provide true benefit for manufacturers, researchers, and clinicians. Objective: This study was designed to develop and evaluate a mediator release assay based on rat basophil leukemia cells for the purpose of investigating allergenic extracts. Methods: Rat basophil leukemia cells were passively sensitized with murine IgE raised against allergens and stimulated by serial dilutions of allergenic extracts in a dose-related manner. The allergen-specific degranulation was monitored by measuring the release of β-hexosaminidase. Results: The investigation of standardized commercial allergen products for in vivo diagnostics (birch pollen, cat dander, and bee venom) allowed a quantitative description of differences in biologic activity in accordance with the declared activity units. The Fel d 1 content was determined in 17 cat dander extracts and correlated well with the results of a two-site binding ELISA ( r = 0.93, log/log). Extremely low allergen amounts in the range of 10 to 100 pg/ml could be easily detected. Moreover, the cross-reactivity pattern of patients allergic to birch pollen could be reproduced with extracts of hazel, alder, apple, and celery. Conclusion: The assay is suitable for supplementing quality control of allergenic extracts and for the determination of biologic activity of final allergen products. As a research tool, it allows the study of IgE cross-linking properties of modified and recombinant allergens at an early stage before they are tested in human beings. (J Allergy Clin Immunol 1997;99:227-32.)

Identification of microorganisms by traditional microbiological methods is time consuming. The German Federal Health Office has developed a method using mid-infrared spectroscopy to identify microorganisms rapidly. This method has been modified for application to microorganisms important in the dairy industry. Mid- and near-infrared spectroscopies are well-established methods for quantitative measurements of fat, protein, lactose, and solid content in a variety of products. A disadvantage of both methods is the huge absorption due to water; extraction of other components is complicated and can be achived only statistically. With Raman spectroscopy, water causes less absorption. We investigated the use of Raman spectroscopy as a quantitative method for milk powder.

Bei Volvo im Werk Torslanda in Schweden lackieren seit August letzten Jahres Roboter die Ausenhaut der Karossen. Der Lackverbrauch sank durch diese Umstellung um rund 10 Prozent.

The molybdenum alloy TZM (Mo-0.5wt%Ti-0.08wt%Zr) is a commonly used constructional material for high-temperature applications. It is well known that molybdenum and its alloys develop a distinct subgrain structure and texture during hot deformation. These microstructural aspects have a significant effect on strength at elevated temperatures. It was observed that with proceeding primary recrystallization and therefore with disappearance of subgrains the yield strength drops almost to the level of pure molybdenum. The aim of the present work was to investigate and describe the strain hardening of hot deformed TZM on a microstructural basis. For this purpose sintered and prerolled TZM rods were recrystallized and each of them deformed to a specific degree of deformation afterwards. Especially the evolution of disorientation distributions was analyzed by electron backscattering diffraction (EBSD) and used to describe the work hardening effect. The yield strength was determined by tensile tests between room temperature and 1473 K. By analyzing disorientation profiles the formation and evolution of geometrically necessary and incidental dislocation boundaries could be observed. A model developed by Pantleon was used to describe the work hardening of TZM.

The Pr and Pfr forms of phytochrome in H2O and D2O have been studied by Fourier transform resonance Raman spectroscopy with near-infrared excitation (1064 nm). It is demonstrated that this technique is a powerful method for analyzing the chromophore structures of photosensitive pigments. The high spectral quality allows discussion of vibrational assignments based on an empirical approach using previously published data obtained from model compounds. The reduction in intensity of a high-frequency band assigned to the ring-C/D methine bridge vibration is an indication for the non-coplanarity of the ring D in Pfr. The high intensity of a C-H out-of-plane vibration also supports this hypothesis. In Pr, a broad peak at approximately 1100 cm-1 is assigned to an out-of-plane vibration of a strongly hydrogen-bonded pyrrole C=NH+ group. It is missing in Pfr, suggesting deprotonation of the corresponding ring during the transformation from Pr to Pfr.

Preresonance Raman and resonance Raman spectra of the primary donor (P) from reaction centers of the Rhodobacter (Rb.) sphaeroides R26 carotenoidless strain in the P and P+ states, respectively, were obtained at room temperature with 1064-nm excitation and a Fourier transform spectrometer. These spectra clearly indicate that the chromophore modes are observable over those of the protein with no signs of interference below 1800 cm-1. The chromophore modes are dominated by those of the bacteriochlorophylls (BChl a), and it is estimated that, in the P state, ca. 65% of the Raman intensity of the BChl a modes arises from the primary donor. This permits the direct observation of a vibrational spectrum of the primary donor at preresonance with the excitonic 865-nm band. The Raman spectrum of oxidized reaction centers in the presence of ferricyanide clearly exhibits bands arising from a BChl a+ species. The magnitude of the frequency shift of a keto carbonyl of neutral P from 1691 to 1717 cm-1 upon P+ formation strongly suggests that one BChl molecule in P+ carries nearly the full +1 charge. Our results indicate that the unpaired electron in P.+ does not share a molecular orbital common to the two components of the dimer on the time scale of the resonance Raman effect (ca. 10(-13) s).

A retrospective 5 year follow-up study was performed in 140 patients with unequivocal ischemia during exercise radionuclide angiography (greater than or equal to 10% decrease in left ventricular ejection fraction or greater than or equal to 5% decrease in ejection fraction together with a distinct regional wall motion abnormality). In 84 patients (60%), ischemia during radionuclide angiography was silent (silent ischemia group), whereas 56 patients experienced angina during the test (symptomatic group). Work load and antianginal medication were similar in both groups. Critical cardiac events (unstable angina, myocardial infarction, cardiac death) occurred in 27% of patients in the silent ischemia group and 16% of those in the symptomatic group (p = NS); however, myocardial infarction or death was more frequent in patients with silent ischemia (22% versus 9%; p less than 0.05). If there was additional exercise-induced ST segment depression, the rate of critical events was further increased (p less than 0.05). The difference in critical cardiac events seemed to be influenced by the higher incidence of revascularization procedures in symptomatic patients, whereas medical therapy had no similar effect. Thus, these findings suggest that patients with documented severe ischemia should undergo left heart catheterization and revascularization irrespective of symptoms to improve their prognosis.

Three [2]catenanes and three [3]catenanes incorporating one or two π-electron-rich macrocyclic polyethers and one π-electron-deficient polycationic cyclophane have been synthesized in yields ranging from 4 to 38 %. The π-electron-rich macrocyclic components possess either two 1,4-dioxybenzene or two 1,5-dioxynaphthalene recognition sites. The π-electron-deficient cyclophane components incorporate two bipyridinium and either one or two dialkylammonium recognition sites. The template-directed syntheses of these catenanes rely on i) π⋅⋅⋅π stacking interactions between the dioxyarene and bipyridinium recognition sites, ii) C−H⋅⋅⋅O hydrogen bonds between some of the bipyridinium hydrogen atoms and some of the polyether oxygen atoms, and iii) C-H⋅⋅⋅π interactions between some of the dioxyarene hydrogen atoms and the aromatic spacers separating the bipyridinium units. The six catenanes were characterized by mass spectrometry and by both 1H and 13C NMR spectroscopy. The absorption spectra and the electrochemical properties of the catenanes have been investigated and compared with those exhibited by the component macrocycles and by related known catenanes. Broad and weak absorption bands in the visible region, originating from charge-transfer (CT) interactions between electron-donor and electron-acceptor units, have been observed. Such charge-transfer interactions are responsible for the quenching of the potentially fluorescent excited states of the aromatic units of the macrocyclic polyether components. The redox behavior of these novel compounds has been investigated and correlations among the observed redox potentials are illustrated and discussed. The catenanes undergo co-conformational switching upon one-electron reduction of the two bipyridinium units. One of them—in its reduced form—can be also switched by acid/base inputs and exhibits AND logic behavior. The co-conformational rearrangements induced by the redox and acid/base stimulations lend themselves to exploitation in the development of molecular-level machines and logic gates. Sono stati sintetizzati tre [2]catenani e tre [3]catenani contenenti un ciclofano policationico π elettron accettore e, rispettivamente, uno e due polieteri macrociclici π elettron donatori, con rese comprese fra 4 e 38 %. I componenti macrociclici π donatori possiedono due unita 1,4-diossibenzene o due unita 1,5-diossinaftalene, mentre il componente π accettore contiene due gruppi dipiridinio ed uno o due gruppi dialchilammonio. La sintesi templata di questi catenani si basa su i) interazioni π⋅⋅⋅π fra i siti di riconoscimento diossiaromatici e dipiridinio, ii) legami a idrogeno C−H⋅⋅⋅O fra atomi di idrogeno dei gruppi dipiridinio ed atomi di ossigeno delle catene polieteree e iii) interazioni C−H⋅⋅⋅π fra atomi di idrogeno delle unita diossiaromatiche e gli spaziatori p-fenilenici che separano i gruppi dipiridinio. I sei catenani sono stati caratterizzati mediante spettrometria di massa e spettroscopia 1H e 13C NMR. Il comportamento elettrochimico e gli spettri di assorbimento dei catenani sono stati esaminati e confrontati con quelli dei componenti macrociclici e di altri catenani simili studiati in precedenza. Si osservano bande di assorbimento deboli e allargate nella regione del visibile, attribuite alle interazioni di trasferimento di carica fra le unita π elettron donatrici e quelle π elettron accettrici. Tali interazioni sono responsabili anche dello spegnimento degli stati eccitati, potenzialmente fluorescenti, localizzati sulle unita aromatiche dei polieteri macrociclici. Dalle correlazioni fra i potenziali dei processi redox osservati si puo concludere che i catenani subiscono riarrangiamenti co-conformazionali in seguito a riduzione monoelettronica dei due gruppi dipiridinio. Uno dei catenani esaminati, nella forma ridotta, da luogo a riarrangiamenti strutturali anche a seguito di stimoli chimici di tipo acido/base, evidenziando un comportamento logico di tipo AND. I movimenti co-conformazionali indotti mediante stimoli redox e acido/base suggeriscono la possibilita di impiegare questi nuovi catenani per la realizzazione di macchine e porte logiche a livello molecolare.

In an attempt to improve survival of patients with coronary artery disease and high-grade ventricular ectopic activity, several studies using different antiarrhythmic drugs were undertaken. A meta-analysis of all randomized controlled trials using type I antiarrhythmic agents showed that the treatment effect was much more likely to be adverse than beneficial. In contrast to these studies, the pooled results of major secondary prevention trials using beta-blocking agents could demonstrate a significant reduction in the sudden death rate by an average of 24% during observation periods of 9-36 months. In the beta-blocker trials, however, patients with contraindications for this type of drug, such as overt congestive heart failure or chronic obstructive lung disease, were excluded. In these patients a type III antiarrhythmic drug, such as amiodarone, may have a place, and in fact, the Basel Antiarrhythmic Study of Infarct Survival, a prospective, controlled, randomized trial using low-dose amiodarone as an antiarrhythmic agent, could demonstrate a 60% reduction in sudden death rate and a 74% reduction in arrhythmic events incidence during the first year after myocardial infarction. Therefore, in patients with repetitive ventricular ectopic activity after myocardial infarction and adequate left ventricular function, a therapeutic attempt with beta-blockers without intrinsic sympathomimetic activity seems advisable. Beside beta-adrenergic blockade, low-dose amiodarone is an alternative, especially in patients with impaired left ventricular function or other contraindications for beta-blockers.

To determine to what extent the effects of phentolamine (PHE) are mediated by the cardiac and vascular beta-receptors, the action of the drug was studied in anaesthetized cats pretreated with beta-blockers. Blockade of the cardiac beta-receptors with either propranolol or metoprolol entirely prevented the increases in heart rate, dP/dt and cardiac output caused by PHE. In animals pretreated with propranolol (in a dose blocking the vascular beta-receptors) or metoprolol (in a purely cardio-selective dose) PHE significantly lowered blood pressure to the same extent as in untreated controls. The effects of PHE on the heart are thus conditional on the integrity of cardiac beta-receptors, whereas it seems improbable that vascular beta-receptors have any part in its vasodilative action. Evidence presented in the literature rather suggests a predominantly central mode of action.

To evaluate the clinical performance of the St Jude Medical bileaflet heart valve prosthesis, we followed 150 consecutive patients (95 male and 55 female patients, mean age 54 years, range 1 to 74 years) for an average of 24 months. These included 74 patients with aortic, 56 patients with mitral, and 20 patients with multiple valve replacement. During the 2 year follow-up, there were a total of four perioperative and seven late deaths, two of which were prosthesis related. Reoperation was necessary in four patients, because of paravalvular leaks in two patients with mitral and one patient with aortic prostheses and because of leaflet dislodgment in one patient with a mitral prosthesis, a postoperative complication that has not been reported previously. The thromboembolic rate per 100 patient-years was 2.6 in aortic and 2.9 in mitral valve replacement, the symptoms being reversible in all patients. All patients were receiving anticoagulant therapy. A total of four complications of anticoagulant therapy (three minor and one fatal) were observed. Significant hemolysis was observed in none of the patients. In patients with dyspnea, the New York Heart Association functional classification was 2.7 +/- 0.8 preoperatively versus 1.3 +/- 0.6 postoperatively. In patients with angina, it was 2.6 +/- 0.6 preoperatively versus 1.03 +/- 0.2 postoperatively. Noninvasive Doppler measurements revealed excellent flow characteristics, values being close to those obtained in natural valves (mean +/- standard deviation of maximal flow velocity: 1.5 +/- 0.5 versus 0.9 +/- 0.1 m/sec in the aortic position; 1.1 +/- 0.3 versus 0.8 +/- 0.3 m/sec in the mitral position).

Persisting symptoms, consisting of palpitations, dizziness, or syncope, were found in 49 of 570 consecutively followed patients (8.6 percent) with permanent pacemakers (PM). Among 540 patients with ventricular PM, 19 had syncope and 24 dizziness; among 30 patients with dual-chamber PM, five had palpitations and one dizziness. Symptoms were PM-related in 17, caused by tachyarrhythmias in 12, of noncardiac origin in 16, and of unknown origin in four patients. Holter monitoring was necessary for evaluating the persisting symptoms in 36 patients and helpful in 32 studies (89 percent). Symptoms were relieved in all patients with PM-related causes but only in 6/16 patients (38 percent) with syncope or dizziness of noncardiac origin despite various therapeutic measures. In patients with either documented tachyarrhythmias or unknown cause of syncope or dizziness, antiarrhythmic drugs led to symptomatic improvement in 11 of 12 treated patients during an average follow-up of 15 months. We concluded that: (1) persistent syncope, dizziness, or palpitations occurred in 8.6 percent of 570 patients after PM-implantation; (2) symptoms were more frequent but less severe in patients with dual-chamber PM than in those with ventricular PM; (3) tachyarrhythmias as a possible cause of symptoms were found in 25 percent of patients; (4) symptomatic improvement was noted in 28 of 29 patients when a PM-related cause or tachyarrhythmias were treated.

In order to assess the influence of preoperative risk factors on the late postoperative course, 186 consecutive patients in whom coronary artery bypass graft (CABG) was performed for chronic stable angina (169 men, 17 women, mean age ±SD 54±8 years) were followed for an average of 54 (6 to 113) months. The overall five-year survival rate by life-table analysis was 90 ±2 percent. The postoperative course was considered favorable in 112 patients (60 percent) in whom angina was absent or improved by at least 2 NYHA classes throughout the entire follow-up, and was unsatisfactory in 74 patients. It was concluded that the late postoperative course of patients with CABG was unfavorably influenced by the presence of two or three risk factors, and a high preoperative cholesterol level was the only single risk factor associated with unsatisfactory outcome.

In order to investigate the relationship between the ease of suppression of complex (frequent multiform, repetitive, and early) ventricular premature beats (VPBs) and subsequent survival, 50 consecutive patients with chronic coronary artery disease (CAD) were followed retrospectively during a mean observation period of 16 months. A total of 124 drug trials were performed using single or combined class I, II, and III antiarrhythmic drugs. Thirty-nine patients were considered "responders" (elimination of Lown classes greater than or equal to IVa and reduction of greater than 30 multiform VPBs to occasional unifocal VPBs during Holter monitoring), whereas in 11 patients VPBs could not be adequately suppressed ("nonresponders"). There were no significant differences in age and congestive heart failure in the two groups. There were three deaths (one sudden) in the 39 "responders" but five deaths (three sudden) in the 11 "nonresponders" (p less than 0.01 for all deaths, p less than 0.05 for sudden deaths). Cumulative probability of survival at 12 months was 0.93 for "responders" and 0.64 for "nonresponders" (p less than 0.005). Significant side effects necessitated drug withdrawal in four patients. Our data suggest that survival in patients with CAD is better when complex VPBs can be suppressed.

Here we show that cold rolling decreased the brittle-to-ductile transitions (BDT) temperature of tungsten (W). Furthermore, we show that the BDT temperature correlates with the grain size (the smaller the grain size, the lower the BDT temperature) following a Hall–Petch-like equation. This relation between the grain size and the BDT temperature is well known from ferrous materials and is generally accepted in the steel community. Our ductilisation approach is the modification of the microstructure through cold rolling. In this work, we assess three different microstructures obtained from (i) hot-rolled, (ii) cold-rolled, and (iii) hot-rolled and annealed (1 h/2000 °C, annealed in H2) tungsten plates. From these plates, Charpy impact test samples with dimensions of 1 × 3 × 27 mm3, without notch, were cut and tested in the L-S and T-S directions. The results show the following BDT temperatures: 675 °C/948 K (L-S, “annealed”), 375 °C/648 K (L-S, “hot-rolled”) and 125 °C/398 K (L-S, “cold-rolled”). The microstructure of the plates is analysed by means of SEM (EBSD: grain size, subgrains, texture, KAM), FIB (channelling contrast) and TEM analyses (bright field imaging). The question of how cold rolling decreases the BDT temperature is discussed against the background of (i) microcracking, crack branching, and crack bridging effects; (ii) texture effects; (iii) the role of dislocations; and (iv) the impact of impurities, micropores, and sinter pores. Our results suggest that the availability of dislocation sources (dislocation boundaries, grain boundaries; in particular, IDBs and HAGBs) is the most important parameter responsible for the increase of the cleavage resistance stress, σF, or the decrease of the BDT temperature, respectively.

The quality ofWeb services is an important factor for businesses that advertise or sell their services in the Internet. Failures can directly lead to fewer costumers or security problems. However, the testing of complexWeb services that are organized in service-oriented architectures is a difficult and complex problem. Model-based testing (MBT) is one solution to deal with the complexity of the testing. With MBT, testers do not define the tests directly, but rather specify the structure and behavior of the System Under Test using models. Then, a test strategy is used to derive test cases automatically from the models. However, MBT yields a large amount of tests for complex systems which require lots of resources for their execution, thereby limiting its potential. Within this article, we discuss how cloud computing can be used to provide the required resources for scaling up test campaigns with large amounts of test cases derived using MBT. peerReviewed

A novel multi-volatile method (MVM) using sequential dynamic headspace (DHS) sampling for analysis of aroma compounds in aqueous sample was developed. The MVM consists of three different DHS method parameters sets including choice of the replaceable adsorbent trap. The first DHS sampling at 25 °C using a carbon-based adsorbent trap targets very volatile solutes with high vapor pressure (20 kPa). The second DHS sampling at 25 °C using the same type of carbon-based adsorbent trap targets volatile solutes with moderate vapor pressure (1-20 kPa). The third DHS sampling using a Tenax TA trap at 80 °C targets solutes with low vapor pressure (1 kPa) and/or hydrophilic characteristics. After the 3 sequential DHS samplings using the same HS vial, the three traps are sequentially desorbed with thermal desorption in reverse order of the DHS sampling and the desorbed compounds are trapped and concentrated in a programmed temperature vaporizing (PTV) inlet and subsequently analyzed in a single GC-MS run. Recoveries of the 21 test aroma compounds for each DHS sampling and the combined MVM procedure were evaluated as a function of vapor pressure in the range of 0.000088-120 kPa. The MVM provided very good recoveries in the range of 91-111%. The method showed good linearity (r20.9910) and high sensitivity (limit of detection: 1.0-7.5 ng mL(-1)) even with MS scan mode. The feasibility and benefit of the method was demonstrated with analysis of a wide variety of aroma compounds in brewed coffee. Ten potent aroma compounds from top-note to base-note (acetaldehyde, 2,3-butanedione, 4-ethyl guaiacol, furaneol, guaiacol, 3-methyl butanal, 2,3-pentanedione, 2,3,5-trimethyl pyrazine, vanillin, and 4-vinyl guaiacol) could be identified together with an additional 72 aroma compounds. Thirty compounds including 9 potent aroma compounds were quantified in the range of 74-4300 ng mL(-1) (RSD10%, n=5).

Here we show that cold-rolling is a method to achieve room-temperature ductility in commercial purity, monolithic tungsten (W). Furthermore, we show that a decrease in rolling temperature concomitantly increases the strength and ductility of tungsten. So cold-rolling is a way to overcome the strength–ductility trade-off. In this work, we assess three different cold-rolled microstructures obtained from rolling at (i) 1000 °C (1273 K), (ii) 800 °C (1073 K), and (iii) 600 °C (873 K). Benchmark experiments were performed on a sintered ingot as well as on a hot-rolled plate. From these plates tensile test specimens were cut by spark erosion and tested at room temperature. The results show an increase of total uniform elongation, A ut , ranging from 1.38% (cold-rolled at 1000 °C (1273 K), and 800 °C (1073 K)) up to 1.47% (cold-rolled at 600 °C (873 K)) and an increase of the total elongation to fracture, A t , ranging from approximately 3% (cold-rolled at 1000 °C (1273 K), and 800 °C (1073 K)) up to 4.19% (cold-rolled at 600 °C (873 K)) with decreasing rolling temperature. The microstructure of the plates is analysed by means of scanning electron microscopy (SEM) (grain size, subgrains, crystallographic texture) and transmission electron microscopy (TEM) (bright field imaging, scanning TEM). Furthermore, strain-rate jump tests have been performed at 400 °C (673 K) to determine the strain-rate sensitivity, m , (sintered ingot m = 0.088, cold-rolled at 600 °C (873 K) m = 0.011) and the activation volume, V , (hot-rolled W plate V = 191 b 3 , cold-rolled at 600 °C (873 K) V = 111 b 3 ) of the tungsten sheets. The question of why cold-rolling increases both strength and ductility is discussed against the background of cold-rolling-induced lattice defects. We speculate that the increase of ductility is caused by the ordered glide of screw dislocations, that move with low deformation incompatibility along the high-angle grain boundary (HAGB) channels (confined plastic slip).

Here we elucidate the mechanisms of plastic deformation and fracture of tungsten laminated composites. Our results suggest that the mechanical response of the laminates is governed by the plastic deformation of the tungsten plies. In most cases, the impact of the interlayer is of secondary importance. Severely cold-rolled ultrafine-grained tungsten foils possess exceptional properties in terms of brittle-to-ductile transition (BDT), toughness, and tensile ductility. The motivation for investigating laminated composites is to determine whether a bulk material can be made that retains the ductility of the thin tungsten foils. In this paper we analyse W-AgCu, W-Cu, W-V, and W-Pd laminates in their as-produced and annealed conditions (e.g. 10, 100 and 1000 h at 1000 °C (1273 K) in vacuum). The analyses comprise (i) the mechanical characterisation by means of three-point bending (damage tolerance), Charpy impact (BDT), and tensile tests (total elongation to fracture) as well as (ii) the in-depth analyses of the microstructure by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Auger electron spectroscopy (AES). W-Cu laminates (60 vol% W) show 15.5% total elongation to fracture in a tensile test at room temperature. Furthermore, the BDT of tungsten laminated composites occurs at a temperature that is several hundreds of Kelvin lower than the BDT temperature of the pure tungsten bulk counterparts. Finally, we present the successful fabrication of a 1000 mm long W-Cu laminated pipe and show its high heat flux performance. Fabrication studies of high heat flux components made of tungsten laminates, in which the laminates are used either as heat spreaders or structural pipes, are presented.

From November 1978 to June 1986, 743 patients received 828 ST. JUDE MEDICAL® valves (SJM) at the University Clinics of Basel, Berne, and Lausanne, Switzerland. There were 445 men and 298 women, with a mean age of 57 years (range 1–83 years), who were followed for a mean of 2.6 years (22,768 patient-months). Aortic valve replacement (AVR) was performed in 456 patients, mitral valve replacement (MVR) in 200 patients, tricuspid valve replacement (TVR) in 6 patients, double valve replacement in 77 patients, and triple valve replacement in 4 patients. In 187 patients, additional surgical interventions were performed. Operative mortality for the entire population was 1.6% and the 4-week perioperative mortality was 4.0%. During the mean follow-up period of 2.6 years, an additional 58 patients died, accounting for an annual mortality rate of 3.1%. Eighteen of these patients died of noncardiac causes, leaving an annual cardiac mortality rate of 2.1%. The thromboembolic rate was 1.25% per patient-year after AVR, 3.0% per patient-year after MVR, and 1.1% per patient-year after MuVR. In 8 of 32 patients (25%) with thromboembolic complications, symptoms were irreversible and in 14 of 32 patients (44%), the prothrombin time was not within therapeutic range. The incidence of major bleeding complications was 1.3% per patient-year.

Optical micro methods have an enormous potential of supplying analytical information: For every volume element complete spectra may be recorded. Since these techniques are non-destructive repeated analyses may be made even from precious samples. Micro techniques applying the methods of vibrational spectroscopy may supply detailed information concerning the composition of a sample, the identity and the structure of its components. The resolvable volume element is determined by the resolving power of the microscope and by the minimal amount of sample defined by the limit of detection. For Raman microscopes this is in the order of 1 cubic micrometer, for infrared microscopes in the order of 1000 cubic micrometers. Microscopes, however have an optical conductance) inferior to that of modern spectrometers. A compromise has to be found between the utilizable Raman light flux and spatial resolution. Both cannot be maximal under the same conditions. FT IR microscopes as well as Raman microscopes with dispersive spectrometers are supplied by several companies. The recently developed NIR FT Raman spectroscopy2 has the advantage of being essentially immune against fluorescence of impurities or products of decomposition.

Ten patients with prosthetic heart valve dysfunction, subsequently verified by invasive methods, were examined by a noninvasive continuous-wave Doppler ultrasound technique. Two cases of obstruction (one mitral, one tricuspid) were identified by either abnormal atrioventricular pressure half-time or by an abnormal flow pattern. Nine of 10 suspected paraprosthetic leaks in aortic, mitral and tricuspid prostheses were correctly diagnosed by detection of regurgitant flow. Experimental obstruction and regurgitation of aortic prostheses in two dogs was also detected by the Doppler method and a close correlation (r = 0.97) was found between pressure gradients measured directly and those calculated from Doppler data. Normal values of flow measurements in physiological and in three different types of prosthetic valves were established in 91 patients. All mean values were slightly, but significantly higher in prosthetic than in normal valves (p < 0.05). Our data suggest that Doppler ultrasound is a valuable method for noninvasive assessment of prosthetic heart valve function.

Raman spectroscopy is a powerful complement to infrared spectroscopy due to experimental as well as theoretical aspects: However, 'classical' Raman spectroscopy is not commonly used. This is mainly due to the fact that the fluorescence of minute amounts of impurities, excited by the radiation in the UV or visible range can mask the Raman spectra completely. NIR FT Raman spectrometers' have several advantages. As exciting light usually the radiation of the Nd-doped YAG laser at a wavelength of 1064 nm is used. Problems with fluorescing samples are largely reduced. There is the 'throughput advantage' of the Michelson interferometer and its high wavenumber accuracy. However, the intensity of the Raman radiation is inversely proportional to the fourth power of its absolute frequency. Laser light fluxes larger by the ν4-factor of about 30 are necessary to achieve the same radiance of the Raman lines in the NIR compared to the visible region. This enhances the danger of pyrolysis of the sample. In order to reduce this danger the whole instrument should have the largest possible optical conductance. Interferometers are therefore appropriate when they are properly matched to a sample arrangement with maximal efficiency.

A 32-year-old woman with prolapsed mitral valve was treated with flecainide because of an episode of primary ventricular fibrillation. The drug was chosen because several hundred short runs of ventricular tachycardia unrelated to exercise were observed during 24-hour monitoring. Oral medication at a dose of 200 mg twice daily suppressed all repetitive ventricular ectopy. Eighteen months later, however, a further 24-hour recording showed a ventricular arrhythmia which was provoked early in the morning by exercise. Because the tablets were taken late in the evening and early in the morning by exercise. Because the tablets were taken late in the evening and early in the morning it was suspected that toxic levels of flecainide may have produced the arrhythmia. Measurement confirmed this suspicion. Reducing the dosage abolished the arrhythmia.

ability to obtain multiple tomographic type images of the heart can confirm the location of the object. In this case the echocardiographic position of the wire was quite certain while the radiographic position was more questionable. Failure to visualize pacemaker wires or catheters is quite possible, however, if the plane of the 2DE beam does not cut across the path of the catheter or wire. The spatial orientation available from 2DE along with the ability to obtain multiple tomographic images of the heart make the technique very useful for the detection of intracavitary structures. Previous reports have documented detection of transvenous pacemaker perforation and in this case the detection of epicardial pacemaker perforation is confirmed. 2DE should be considered complementary to the usual studies available for the analysis of malfunctioning pacemaker leads.