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The development of efficient strategies for the treatment of the dynamics of relevant observables in complex quantum systems plays a decisive role in the theory of quantum relaxation and transport behavior. Here we discuss the most important tools that are based on the projection operator techniques of nonequilibrium statistical mechanics. For both the Nakajima-Zwanzig and the time-convolutionless projection operator technique we derive the equations of motion for a set of relevant observables and develop explicit expressions in second and fourth order of the corresponding perturbation expansions. We also discuss the Hilbert space average method which is based on the idea of a best guess of conditional quantum expectations determined by an average over a suitable region in the underlying Hilbert space, and relate this method to the projection operator technique.

We analyse the excitation mechanisms which determine the dynamics of highly excited hydrogen atoms traversing a waveguide. Experimental measurements to verify predictions derived from Floquet theory are suggested.

Abstract:: In a recent experiment the progressive decoherence of a mesoscopic superposition of two coherent field states in a high-Q cavity, known as Schrödinger cat state, has been measured for the first time [Brune et al., Phys. Rev. Lett. 77, 4887 (1996)]. Here, the full master equation governing the coupled dissipative dynamics of the atom-field system studied in the experiment is formulated and solved numerically for the experimental parameters. The model simulated avoids the approximations underlying an analytically solvable model which is based on a harmonic expansion of the energies of the dressed atomic states and on a treatment of their dynamics within the adiabatic approximation. In particular, the numerical simulations reveal that the coupling of the cavity field mode to its environment causes important decoherence effects already during the initial preparation phase of the Schrödinger cat state. This phenomenon is investigated in detail with the help of a measure for the purity of states. Moreover, the Hilbert-Schmidt distance of the intended target state, the Schrödinger cat, to the state that is actually prepared in the experiment is determined.

Abstract:: A rigorous extraction of the deuteron charge form factors from tensor polarization data in elastic electron-deuteron scattering, at given values of the 4-momentum transfer, is presented. Then the world data for elastic electron-deuteron scattering is used to parameterize, in three different ways, the three electromagnetic form factors of the deuteron in the 4-momentum transfer range 0-7 fm−1. This procedure is made possible with the advent of recent polarization measurements. The parameterizations allow a phenomenological characterization of the deuteron electromagnetic structure. They can be used to remove ambiguities in the form factors extraction from future polarization data.

The Brugada-Brugada syndrome is a rhythmologic disorder which can be diagnosed because of typical ECG criteria. A high-take off descending ST segment localized to the right chest leads, associated with right bundle branch block and ventricular fibrillation or syncopes are characteristic of the syndrome. ECG alterations in the right precordial leads were recorded in a 47 year old female patient who was admitted to hospital because of enteritis and associated syncope. The ECG alterations were initally not realized as Brugada-Brugada syndrome. Because of “recognizing” comparable ECG alterations during a congress lecture, the diagnosis was made. The patient was treated with an ICD. Das Brugada-Brugada-Syndrom ist ein anhand typischer EKG-Kriterien erkennbares rhythmologisches Krankheitsbild, welches familiär gehäuft zu Kammerflimmern oder Synkopen führt. Ein hoher ST-Strecken-Abgang mit zeltförmig deszendierendem Verlauf in den rechtspräkordialen Ableitungen, verbunden mit einem rechtsschenkelblockartig verbreiterten Kammerkomplex ist charakteristische für das Syndrom. Bei einer 47jährigen Patientin wurden während einer Enteritis mit begleitendem Kollaps rechtsventrikulär lokalisierte EKG-Veränderungen gesehen, jedoch primär nicht im Sinne eines Brugada-Brugada-Syndroms interpretiert. Erst nach “Wiedererkennen”ähnlicher EKG-Veränderungen wie bei der 47jährigen Patientin anläßlich eines Kongresses wurde die wegweisende Diagnostik eingeleitet. Präventiv erhielt die Patientin einen ICD.

Summary To investigate the effects of several endoscopic procedures like introduction of the bronchoscope, removal of the instrument, catheter suction, bronchoalveolar lavage and transbronchial biopsy on heart rate, systemic blood pressure, and transcutaneously measured blood gases 77 consecutive patients (age, 20–83 years) were studied. All patients received 10 l O2/min via face mask during bronchoscopy. Sedation was performed with midazolam or diazepam. The different characteristics of each patient, e.g. age, sex, smoking habits, baseline values of heart rate and systemic blood pressure, underlying pulmonary disease and kind of premedication were examined separately to analyse their special effects on the course of bronchoscopy.

Summary Plasma renin activity (PRA) was measured in five healthy women and four healthy men at hourly intervals during a period of 24–25 hrs. PRA was determined by measuring radioimmunologically angiotensin I which was liberated during incubation of the plasma sample for 1 hr. at pH 5.9. In all subjects, a significant increase of PRA was found at the beginning of the sleeping phase (23.00–2.00). This increase was relatively small in women whose PRA was low during the day. Apart from some intra-individual variations, PRA was always higher during the sleeping phase than during the active phase. In subjects with a short sleeping phase (approximately 5 hrs.), PRA remained elevated for some time after awaking; in contrast, after a longer period of sleep (approximately 8 hrs.), PRA soon returned to the basic values, observed during the active phase. Intra-individual variations were found independent of short term orthostatic stress. In one patient with untreated depressive psychosis, no circadian rhythm

Bei 14 gesunden jungen Frauen erfolgten in 48stündigem Abstand über jeweils einen menstruellen Zyklus hinweg Blutentnahmen unter kontrollierten Bedingungen (nüchtern morgens vor dem Aufstehen); die Konzentrationen von Reninsubstrat, Aldosteron, LH, FSH, Östradiol-17ß, Progesteron, 17a-Hydroxyprogesteron, 4-Androstendion und Prolaktin sowie die Reninaktivität im Plasma wurden bestimmt und ihr Verhalten verglichen.

Ohne Zusammenfassung:

Carcinoembryonic antigen (CEA) was localized in various embryonic and fetal human tissues between 8 and 16 weeks of gestation as well as in the colorectal mucosa of older fetuses, newborns and adults. Among the embryonic tissues, CEA was always present in the esophagus, the gastric antrum, the duodenum and the rectum. CEA positive staining of bile cannaliculi of the liver was inconstant. All other embryonic tissues were CEA negative. During early fetal development CEA positive staining of the esophagus, antrum and duodenum was inconstant. However, the whole colon became intensively stained. An inconstant CEA specific staining was found in parts of the midgut and in the bile cannaliculi of the liver. The other organs remained CEA negative. Between the 17th week of gestation and birth, CEA staining pattern of the colorectal mucosa did not change. The staining intensity of late fetal colonic mucosa was similar to that of adult colonic mucosa.

A highly sensitive method for the immuno-histochemical localisation of carcinoembryonic antigen (CEA) is described. This method is based on the binding of a peroxidase-antiperoxidase complex (PAP) to anti-CEA antibodies by means of an anti-gamma-globulin which reacts with both the anti-CEA and the antiperoxidase antibodies. Using the technique described here, CEA was localised in conventionally processed normal and cancerous colonic tissue. In normal as well as in neoplastic tissues, a CEA-specific staining of cell membranes and cytoplasm was demonstrated. In frozen sections of normal colonic tissue CEA was found even at high dilutions of the first antibody; this indicates the high sensitivity of the method. The applicability of the method to conventionally processed and thereby well preserved tissue specimens opens the possibility to identify CEA by light microscopy even at very low concentrations.

In this paper a new approach to computational fluid dynamics is introduced in which the fluid is regarded as a stochastic dynamical system. The velocity of the fluid is related to a stochastic process governed by an appropriate master equation acting in a discrete phase space. The method is explained by means of (1 + 1)-dimensional flow phenomena. It is shown that the stochastic approach naturally leads to transparent numerical algorithms for stochastic simulations of fluid motion. By simulating plane Poiseuille flow it is demonstrated that the probabilistic approach yields a correct description of laminar fluid motion. Furthermore, soliton-like and shock wave solutions of Burgers' equation are generated by stochastic simulations of the underlying stochastic process.

Stochastic differential equations are investigated which reduce in the deterministic limit to the canonical equations of motion of a Hamiltonian system with one degree of freedom. For example, stochastic differential equations of this type describe synchrotron oscillations of particles in storage rings under the influence of external fluctuating electromagnetic fields. In the first part of the article new numerical integration algorithms are proposed which take into account the symplectic structure of the deterministic Hamiltonian system. It is demonstrated that in the case of small white noise the algorithm is more efficient than conventional schemes for the integration of stochastic differential equations. In the second part the algorithms are applied to synchrotron oscillations. Analytical approximations for the expectation value of the squared longitudinal phase difference between the particle and the reference particle on the design orbit are derived. These approximations are tested by comparison with numerical results which are obtained by use of the symplectic integration algorithms.

We develop a method that allows the investigation of adiabatic evolution in periodically driven quantum systems. It is shown how Berry's geometrical phase emerges in quantum optics. We analyse microwave experiments performed on Rydberg atoms and suggest a new, non-perturbative mechanism to produce excited atomic states.

Abstract:: The pion absorption reaction (π+,3 p ) on Ar was studied at pion energies of 70, 118, 162 and 239 MeV, and on N and Xe at 239 MeV. The 3p cross section with a 50 MeV cut on the missing energy is presented. The existence of an initial state interaction (ISI) component to the reaction was investigated. The portion of the 3p cross section assigned to the ISI process is less than one half and at lower energies significantly so.

General repercussions of the extraordinarily rich avoidedcrossing structure in the parametric dependence of quasi-energies are discussed. A coarse-graining procedure leading to smooth effective quasienergy surfaces is introduced. New features and their experimental consequences encountered in the attempt of attaining an adiabatic limit are elucidated. Si discutono ripercussioni generali della struttura straordinariamente ricca a incrocio evitato nella dipendenza parametrica delle quasi energie. Si introduce un procedimento a grana grossa che porta a superfici liscie di quasi energia efficaci. Si chiariscono nuove caratteristiche e le loro conseguenze sperimentali incontrate nel tentativo di ottenere un limite adiabatico. Обсуждаются общие отражения для структур в случае параметрической зависимости квази-энергий. Вводится процедура, приводящая к гладким эффективным поверхностям квази-энергии. Анализируются новые особенности и их экспериментальные следствия, возникающие при попытке получения адиабатического предела.

In human and small animal intensive care medicine percutaneous sheath introducer (PSI) sets are commonly used for repeated insertion of an arterial or a venous catheter with only one vascular puncture.We used PSI for chronic catheterization of swine with a Swan-Ganz thermodilution catheter via a surgically exposed external jugular vein. In this way we were able to change defective catheters or correct the position of the catheter tip without renewed surgical intervention.

After incubation of 1,3,5(10),16-oestratetraenol, a 16-dehydrosteroid, with rat liver microsomes, 16α,17α-epoxy-oestratrienol was isolated as metabolite. The compound was detected by the use of mass fragmentography after purification of the incubation extract by thin-layer chromatography. Since the epoxide is rapidly hydrolysed by a hepatic epoxide hydratase, only very small concentrations of this metabolite were present in the incubation extract. When styrene oxide was added to the incubation mixture as inhibitor of the epoxide hydratase, the yield of the steroid epoxide increased considerably. Final identification of the oestrogen epoxide was performed by recording mass spectra and by comparison with authentic reference material.

Branching ratios for proton and α-particle decay of hole states in 16O have been determined from a 17O(d, tc) coincidence experiment. Total widths have been measured in s supplementary 17O(3He, α)16O experiment. Proton decay of stretched d5/2· p3/2−states to the p1/2−ground state of 15N is interpreted in terms of a nuclear Auger effect.

Photometrically measured values of O2-saturation (SO2) were compared with SO2 predictions on the basis of the equations proposed by Heck, Kelman, Lutz, Marsoner, Severinghaus, and Siggaard-Andersen on 1350 occasions. Capillary, venous and mixed venous blood samples from 23 healthy subjects and 30 patients, suffering from cardio-pulmonary diseases were analyzed at rest, during exhaustion, limited exercise and during the recovery phase of ergometric tests. Overall the best agreements with the measured values were found for the equations of Kelman, Severinghaus and Siggaard-Andersen. The results of Heck's, Lutz', and Marsoner's preditions were in reasonable agreement with the measured SO2 only under special physiological conditions. No calculation mode can be performed with constant accuracy and reliability when covering a wide range of acid-base values. If SO2 values are used for further calculations e.g. for determination of cardiac output, measured values are preferred.

Zusammenfassung Bei acht ovariektomierten Frauen wurde die Wirkung hoher Dosen von Äthinylostradiol (0,4 mg täglich) auf die Reninsubstratkonzentration, die Reninaktivität und die Aldosteronkonzentration im Plasma untersucht. Die Konzentration von Reninsubstrat (Angiotensinogen) im Plasma stieg schon innerhalb von 24–28 h an und erreichte ein Maximum zwischen dem dritten und fünften Tag nach Beginn der Östrogenbehandlung. Der Anstieg der Plasmareninaktivität war weniger deutlich ausgeprägt und zeigte große interindividuelle Unterschiede; eine statistische Signifikanz konnte nur 48 h nach Einnahme der ersten Dosis von Äthinylöstradiol nachgewiesen werden. Die Aldosteronkonzentration stieg bei zwei von vier untersuchten Versuchspersonen ebenfalls an. Bei einer Patientin, die mit 5 mg Östradiolbenzoat i.m. behandelt worden war, wurde ein Anstieg der Plasmareninaktivität ohne gleichzeitige Veränderung der Reninsubstratkonzentration beobachtet. Auch während der Einnahme von Äthinylostradiol stieg bei einer Versuchsperson die Reninaktivität schon vor der Reninsubstratkonzentration an. Somit erscheint es möglich, daß Östrogene nicht nur die Synthese von Reninsubstrat in der Leber, sondern außerdem auch die Reninfreisetzung in der Niere stimulieren.

The uptake of [4-14C]oestriol by the isolated perfused rat liver is 3.8 times faster as compared to that of simultaneously perfused [6,9-3H2]oestriol 16α-monoglucuronide. During perfusion the concentration of both radioactive oestrogens decreased exponentially in perfusion medium (apparent kel: 0.061 min−1and 0.016 min−1, respectively). [6,9−3H2]Oestriol 16α-monoglucuronide was metabolized only to a small extent; more than 92% was secreted unchanged into the bile where it was highly concentrated (1800 nmol/g). In contrast [4-14C]oestriol was extensively metabolized; it was mainly hydroxylated at C-atom 2, leading to a rapid increase in the concentration of 2-hydroxyoestriol in the perfused medium. This metabolite was quickly taken up by the liver during recirculation and subsequently either methylated or sulphated. 2-Hydroxyoestriol monosulphate was glucuronated to 2-hydroxyoestriol 16α-monoglucuronide 3-sulphate, which was rapidly excreted into the bile. No double conjugate was formed when [6,9-3H2]oestriol 16α-monoglucuronide was perfused; this is additional evidence for the correctness of the assumption that monoglucuronides cannot serve as precursors of sulphoglucuronides.

Structure-property relationships were investigated for blends of grafted rubbery polymers with PVC. Increasing grafting levels as well as higher blending temperatures improved the dispersion of the graft copolymers in PVC, lowered the impact strength, and reduced stress whitening. Presuming a mechanistic connection between impact strength and stress whitening, the causes of whitening due to mechanical deformations were studied by a variety of methods. Electron microscopy of stress-whitened zones revealed a large number of cavities formed by rupture of rubber particles, which correlated with the extent of whitening. Density measurements and quantitative evaluations of the volume increase due to the cavities in the stress-whitened zones were in agreement and proved that crazing did not significantly contribute to either volume dilation or stress-whitening. Light scattering studies indicated the existence of reflecting planes oriented at an angle of 55 to 64° to the direction of the applied stress, depending on the particle size of the modifier in the blends. The orientation of the scattered light could not be attributed to the cavities in the rubber particles because of their smallness (< 0.5 μm). An explanation was finally found by transmission light microscopy at various resolving powers. It was demonstrated that the ruptured rubber particles were accumulated in bands which corresponded to shear bands in the PVC matrix. Thus it was concluded that the rubber particles improved the impact strength of PVC by initiating shear bands and not by generating crazes.

The activity of the 17β-hydroxysteroid oxidoreductase (17β-HSOR), catalysing the oxidoreduction of oestradiol-17β and oestrone, has been studied in the cytosol fraction of rat liver under various conditions. The activity of the enzyme increased during maturation and reached a plateau at 100 days in females and at 180 days in males. In adult male rats, the activity of the 17β-HSOR was about 60% higher than in adult female rats. When female animals were castrated, the development of enzyme activity was similar to that observed in male rats; there was no difference in enzyme activity between adult castrated female rats and normal male rats. In normal female rats the activity of the 17β-HSOR was high during metoestrus and dioestrus, and low during pro-oestrus and oestrus. These findings show that oestrogens have a repressing effect on the activity of a key enzyme of steroid metabolism in rat liver.

Ovariectomized rats received a single injection of 10 μg oestradiol-17β 3-benzoate; 90 min or 19 h after injection, slices of various brain areas were prepared and incubated with tritiated noradrenaline for 30 min. Methylated and non-methylated metabolites of tritiated noradrenaline were determined after chromatographic separation. Nineteen h after administration of oestradiol-17β 3-benzoate, the formation of normetanephrine, 3-methoxy 4-hydroxy phenylglycol and 3-methoxy 4-hydroxy mandelic acid was decreased (P< 0.05) in hypothalamic tissue, whereas that of 3,4-dihydroxy mandelic acid was increased (P< 0.001). In thalamus tissue a decrease of normetanephrine (P< 0.05) and an increase of 3,4-dihydroxy mandelic acid (P< 0.01) were also observed. No conclusive results were obtained with hypophyseal tissue. The present findings suggest that oestrogens reduce the methylation of noradrenaline, probably through a competitive inhibition of the catechol-O-methyl-transferase by 2-hydroxylated oestrogens.

Plasma concentrations of LH and of sodium, potassium, total protein and haemoglobin were measured in ovariectomised rats during continuous blood withdrawal up to 180 min; 0.45 ml blood samples were taken every 10 min, the total volume of blood removed not exceeding 9 ml. Four groups of animals were studied: group A received no substitution (controls), group B was substituted with 0.9% NaCl-solution, group C with 3.5% polypeptide solution (Haemaccel), and group D with a suspension of washed erythrocytes from the blood removed. During blood withdrawal, the mean values of LH concentrations as well as the amplitudes of the rhythmic LH pulses remained constant in all the animals. However, the rate of pulses was reduced in the control animals and in the group receiving 0.9% NaCl-solution during the period between 90 and 180 min; in contrast no change was observed in the groups C and D during the whole period. The results presented here show that the characteristic LH pattern in ovariectomised rats is not affected by volume depletion, provided the blood is replaced by a solution containing either a polypeptide or a suspension of washed erythrocytes.