Search Results - (Author, Cooperation:D. Guenther)

2014-07-06

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Computer Science

Medicine

Natural Sciences in General

Physics

1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] Porphyry copper–molybdenum–gold deposits are the most important metal resources formed by hydrothermal processes associated with magmatism. It remains controversial, however, whether the metal content of porphyry-style and other magmatic–hydrothermal deposits is dominantly ...

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1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] One puzzle has been why the immunologically competent cells of the foreign marrow are not 'paralysed' in the presence of excess host tissue antigen. If time is required and if the ciitical injury to the host occurs in the first few days, before tolerance or paralysis develops, it might be expected ...

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1435-1536

Springer Online Journal Archives 1860-2000

Chemistry and Pharmacology

Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics

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1572-8099

Springer Online Journal Archives 1860-2000

Architecture, Civil Engineering, Surveying

Abstract Technology is being developed to illustrate the feasibility of determining the temperature of a fire from the spring constant of a spring. Although preliminary in development, the first tests indicate a relationship between a fire's temperature and the spring constant of a heated spring. This discussion is based on studies performed at The Ohio State University.

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1432-1904

Springer Online Journal Archives 1860-2000

Biology

Chemistry and Pharmacology

Natural Sciences in General

Electronic Resource

1432-1904

Springer Online Journal Archives 1860-2000

Biology

Chemistry and Pharmacology

Natural Sciences in General

Electronic Resource

1432-069X

Springer Online Journal Archives 1860-2000

Medicine

Zusammenjassung Ergebnisse der Clotrimazol-Behandlung von 4 Kindern mit chronisch-mucocutaner Candidiasis (Candida Granulomen) werden berichtet. Das orale Breitspektrumantimycoticum Clotrimazol (BAY b 5097) wurde in täglichen Dosen von nahezu 60 mg/kg Körpergewicht verabreicht, bis der Patient klinisch symptomfrei war und der Candida-Nachweis negativ blieb. Bei einem Patienten mit einer 15jährigen Krankheitsanamnese dauerte die Rezidivfreiheit bis jetzt 5 Monate. Jüngere Kinder zeigten leichte Rezidive im Abstand von mehreren Wochen nach Behandlungsbeendigung. Diese Rezidive sind möglicherweise auf eine unzureichende Dosierung zurückzuführen. Die bei jüngeren Kindern erforderliche Langzeittherapie kann zu einem beträchtlichen Widerwillen führen, die die weitere regelmäßige Tabletteneinnahme bei ambulant behandelten Kindern verhindert. Neben geringen Erhöhungen der alkalischen Phosphatase, die jedoch niemals die altersentsprechenden Normalwerte überschritten, konnten Nebeneffekte nicht beobachtet werden.

Summary Results of a clotrimazole treatment of children with chronic mucocutaneous candidiasis (Candida granuloma) are reported. The oral broadspectrum antimycotic clotrimazole (BAY b 5097) was administered in a daily dose of approximately 60 mg/kg body weight until the patient was free of clinical symptoms and until Candida was no longer detectable. One patient who had had the disease for 15 years has had no relapse for 5 months now. The younger children suffered milder relapses several weeks after termination of the treatment. The recurrences may have been due to insufficient dosage. In younger children the need for longterm administration of tablets gives rise to considerable aversion, which can prevent regular ingestion in children treated on an ambulatory basis. Apart from elevation of alkaline phosphatase, which did not go beyond the normal limits for the age, side effects were not observed.

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1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] THE opacity of matter has been measured for the first time at the temperatures and densities that occur in the interiors of stars. Da Silva, of the University of California at Berkeley, and his collaborators at the Lawrence Livermore National Laboratory1 used an X-ray laser to heat a thin sample of ...

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1432-1130

Springer Online Journal Archives 1860-2000

Chemistry and Pharmacology

Abstract A homogenized 193 nm ArF* laser ablation system coupled to an inductively coupled plasma-”Time of Flight”-mass spectrometer (LA-ICP-TOFMS) was tested for depth profiling analysis on different single-layer Ti based coatings on steel and W carbides. Laser parameters, such as repetition rate, pulse energy and spatial resolution were tested to allow optimum depth related calibration curves. The ablation process using a laser repetition rate of 3 Hz, 120 μm crater diameter, and 100 mJ output energy, leads to linear calibration curves independent of the drill time or peak area used for calibrating the thickness of the layer. The best depth resolution obtained (without beam splitter) was 0.20 μm per laser shot. The time resolution of the ICP-TOFMS of 102 ms integration time per isotope was sufficient for the determination of the drill time of the laser through the coatings into the matrix with better than 2.6% RSD (about 7 μm coating thickness, n = 7). Variation of the volume of the ablation cell was not influencing the depth resolution, which suggests that the depth resolution is governed by the ablation process. However, the application on the Ti(N,C) based single layer shows the potential of LA-ICP-TOFMS as a complementary technique for fast depth determinations on various coatings in the low to medium μm region.

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1432-1130

Springer Online Journal Archives 1860-2000

Chemistry and Pharmacology

Abstract Trace elements in microliter quantities of aqueous solutions were analysed by direct liquid ablation using an 193 nm excimer with an inductively coupled plasma mass spectrometer (ICP-MS). Fractionation resulting from splashing and evaporation can be minimised by covering the liquid surface with a thin plastic film, through which a 20 μm hole is drilled with the laser. Particle-size distribution and oxide formation in the plasma resulting from the direct liquid ablation are similar to those generated by solid ablation. The ICP-MS response in cps/ppm is approximately 100 × higher for the direct ablation, but is proportional to the response from solid ablation, within an accuracy 〈 15% for most trace elements in NIST 610 and NIST 612 glass standards. A matrix load up to 2.5 wt.-% NaCl in the solution does not affect the proportionality of trace element responses. Thus, direct liquid ablation is not only suited for analysing small volumes of complex aqueous solutions (e.g., the quantitative microanalysis of fluid inclusions in minerals), but also provides a new approach for calibrating laser ablation ICP-MS microanalysis of solids.

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1432-1130

Springer Online Journal Archives 1860-2000

Chemistry and Pharmacology

Abstract The increased interest in laser technology (e.g. for micro-machining, for medical applications, light shows, CD-players) is a tremendous driving force for the development of new laser types and optical set-ups. This directly influences their use in analytical chemistry. For direct analysis of the elemental composition of solids, mostly solid state lasers, such as Nd:YAG laser systems operating at 1064 nm (fundamental wavelength), 266 nm (frequency quadrupled) and even 213 nm (frequency quintupled) have been investigated in combination with all available inductively coupled plasma mass spectrometers. The trend towards shorter wavelengths (1064 nm– 157 nm) was initiated by access to high quality optical materials which led to the incorporation of UV gas lasers, such as excimer lasers (XeCl 308 nm, KrF 248 nm, ArF 193 nm, and F2 157 nm) into laser ablation set-ups. The flexibility in laser wavelengths, output energy, repetition rate, and spatial resolution allows qualitative and quantitative local and bulk elemental analysis as well as the determination of isotope ratios. However, the ablation process and the ablation behavior of various solid samples are different and no laser wavelength was found suitable for all types of solid samples. This article highlights some of the successfully applied systems in LA-ICP-MS. The current fields of applications are explained on selected examples using 266 nm and 193 nm laser ablation systems.

Electronic Resource

1432-1130

Springer Online Journal Archives 1860-2000

Chemistry and Pharmacology

Abstract Simultaneous ion sampling and sequential detection offered by inductively coupled plasma ‘time of flight’ mass spectrometry (ICP-TOFMS) provides advantages for the analysis of short transient concentration-variable signals as produced in laser ablation. In order to investigate the capabilities of ICP-TOFMS in combination with an excimer laser ablation system, ablation studies on reference materials and geological samples were carried out. Various ICP-TOFMS parameters were optimized for laser-induced aerosols. Transverse rejection ion pulse was used to extend the dynamic range in concentration. A reduced volume ablation cell was designed and used in order to increase the sample density in the ICP. Results for 63 simultaneously measured isotopes (SRM 610 from NIST) lead to limits of detection in the 1–100 μg/g range for a 80 μm crater diameter (10 Hz, 1.2 mJ pulse energy). The reproducibility of signal ratios was determined to be better than 2% RSD for transient signals using 102 ms integration time. These optimized parameters were then used for the analysis of tin-rich fluid inclusions. Preliminary results of multielement analysis and isotopic ratio determinations on individual fluid inclusions (63 isotopes, 102 ms integration time) demonstrate the capabilities of ICP-TOFMS in combination with laser ablation.

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1432-2048

Cadmium stress ; Heat stress ; Lycopersicon

Springer Online Journal Archives 1860-2000

Biology

Abstract Cell cultures of Lycopersicon peruvianum L. stressed with CdSO4 (10−3M) show typical changes in the ultrastructure, starting with the plasmalemma and later on extending to the endoplasmic reticulum and the mitochondrial envelope. Part of the membrane material is extruded, with the formation of osmiophilic droplets which increase in size and number during the stress period. After 4 h, about 20‰ of the cells are dead. A short heat stress preceeding the heavy-metal stress induces a tolerance effect by preventing the membrane damage. The cells show a normal ultrastructure with one exception: cytoplasmic heat-shock granules are formed. This protective effect can be abolished by cycloheximide. Cadmium uptake is not markedly influenced by the heat stress. Cadmium is found together with sulfur in small deposits in the vacuoles of stressed cells. The precipitates contain an excess of sulfur, evidently due to the stress-induced formation of phytochelatins. The role in heavy-metal tolerance of heat-shock proteins in the plasmalemma (HSP70) and in cytoplasmic heat-stress granules (HSP17, HSP70) is discussed.

Electronic Resource

1432-0967

Springer Online Journal Archives 1860-2000

Geosciences

Abstract Zircon and monazite from granulite- to amphibolite-facies rocks of the Vosges mountains (central Variscan Belt, eastern France) were dated by ion-microprobe and conventional U-Pb techniques. Different granulites of igneous (so-called leptynites) and sedimentary origin (kinzigites) and their leucosomes were dated at 334.9 ± 3.6, 335.4 ± 3.6 and 336.7 ± 3.5 Ma (conventional age 335.4 ± 0.6 Ma). Subsequent growth stages of zircon were distinguished by secondary electron (SEM) and cathodoluminescence (CL) imaging: (1) subsolidus growth producing round anhedral morphologies and sector zoning; (2) appearance of an intergranular fluid or melt phase at incipient dehydration melting that first resulted in resorption of pre-existing zircons, followed by growth of acicular zircons or overgrowths on round zircons consisting of planar growth zoning; (3) advanced melting producing euhedral prismatic zircons with oscillatory zoning overgrowing the sector zones. Two further lithologies, the Kaysersberg granite and the Trois-Epis units, were both formerly considered as migmatites. The intrusion of the Kaysersberg granite was dated at 325.8 ± 4.8 Ma. The Trois-Epis unit was found to be the product of volume recrystallization of a former granulite, which occurred under amphibolite-facies conditions 327.9 ± 4.4 Ma ago. The amphibolite-facies overprint of the Trois-Epis zircons led to the complete rejuvenation of most of the zircon domains by annealing and replacement/recrystallization processes. Annealing is assumed to occur in strained lattice domains, which are possibly disturbed by high trace element contents and/or large differences in decay damage between adjacent growth zones. Investigation of cathodoluminescence structures reveals that the replacement occurs along curved chemical reaction fronts that proceed from the surface towards the interior of the zircon. The monazite U-Pb system still records the age of high-grade metamorphism at around 335 Ma. The chemical reagent responsible for the rejuvenation of zircon obviously left the monazite unaffected.

Electronic Resource

1432-0967

Springer Online Journal Archives 1860-2000

Geosciences

Abstract Up to 3 km of dunitic rocks occur below crustal gabbro in the Blow Me Down massif (Bay of Islands Ophiolite, Newfoundland). Analyses of dunite- and gabbro-hosted clinopyroxene grains (cpx) for rare earth elements (REE), Zr, and Ti reveal three types of chondrite-normalized patterns: N-group patterns are similar to cpx grains as they would form by fractionation from a range of mid ocean ridge basalts (MORB). They are typical for a few higher level dunitic samples as well as mafic cumulates. F-group patterns show light REE depletion, very strong middle REE fractionation and a positive Zr anomaly and occur in dunites only. R-group patterns are severely depleted in both light and heavy REEs relative to MORB-like cpx and two samples of the group display a positive Ti anomaly. They are also restricted to dunitic rocks. The patterns are explained in a two stage model in which an established dunite sequence, dominated by MORB-type cumulate signatures (N-group), was infiltrated by extremely refractory melts. During infiltration of the refractory melt chromatographic fractionation occurred, transforming N-group dunites into F-group and R-group dunites. The F-group patterns are composite patterns: heavy REE, Ti ± Zr reflect the original MORB-like cumulate dunite host, light REEs indicate equilibrium with the infiltrating, refractory melts. Steep slopes in the middle REEs reflect the position of the chromatographic front. For more intense percolation of refractory melts, R-group patterns with a positive Ti anomaly will form by the same process. The rest of the R-group patterns displaying no positive Ti anomaly may represent either the most intensely reacted host rocks or these dunites derive directly as cumulates from refractory melts. Only small volumes of refractory melt (a 5 m column) are required to imprint the observed trace element pattern on the thick original dunite sequence. One of several possible origins for the refractory melts is transformation of original MORB-type melts by way of chromatographic fractionation within the highly depleted, residual uppermost mantle. In the framework of an oceanic spreading centre, the migrating, refractory liquids are considered a late event following the main constructive stage dominated by aggregated melts. The study demonstrates that highly refractory melts can exist under oceanic spreading centres dominated by a MORB-like cumulate and volcanic sequence.

Electronic Resource

1432-1440

Springer Online Journal Archives 1860-2000

Medicine

Electronic Resource

1435-2451

Diaphragm, defects, congenital ; Approach, surgical, abdominal/thoracic ; Comparison, retrospective ; Kindliche Zwerchfelldefekte ; thorakaler und abdominaler Zugang ; vergleichende Spätergebnisse

Springer Online Journal Archives 1860-2000

Medicine

Zusammenfassung Operation von 45 kindlichen kongenitalen Zwerchfelldefekten von 1956-1972. Operation bei Neugeborenen dringend, bei älteren Kindern elektiv. 29mal thorakales, 16mal abdominales Vorgehen. Etwa 50% Zusatzanomalien, deswegen hohe Operationsmortalität von 17,8%. Klinische, spirometrische und röntgenologische Nachuntersuchungen von 26 Patienten 4–20 Jahre nach der Operation. Ergebnisse: Alle subjektives Wohlbefinden, leichte bis mäßige respiratorische Ventilationsstörungen, Thoraxdeformitäten oder Skoliosen, bei der thorakal operierten Gruppe häufiger. Pleuraschwarten, Minderung der Zwerchfellbeweglichkeit, Minderbelüftung der Lunge gleich häufig bei beiden Gruppen.

Summary From 1956-1972, 45 children received surgical treatment for congenital defects of the diaphragm. Surgery is essential in neonates, but optional in older children. The approach was thoracic in 29 cases and abdominal in 16. Other anomalies were found in about 50 percent of cases, so that there was a high mortality rate of 17.8 percent. Clinical, spirometric, and radiographic follow-up examinations were carried out in 26 patients 4–20 years after the operation. All felt well; slight or moderate respiratory difficulties, thoracic deformities or scoliosis were noted in some patients, and these were commoner in patients in whom a thoracic approach had been used. Pleural scars, restricted diaphragmatic motility, and respiratory insufficiency were equally common in both groups.

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1435-1285

Schlüsselwörter Ambulante kardiale Rehabilitation – koronare Herzkrankheit – körperliche Leistungsfähigkeit – Herzfrequenz – Laktat ; Key words Ambulatory cardiac rehabilitation – coronary artery disease – physical performance – heart rate – lactate acid

Springer Online Journal Archives 1860-2000

Medicine

Summary During a 4-week ambulatory cardiacc rehabilitation program, 262 patients with coronary artery disease (CAD), 235 men and 27 women, 53.6±10.2 years, performed 30.5±2,9 exercise units. Before and after the rehabilitation program exercise, capacity was assessed by bicycle ergometry. There was a significant (p〈0.001) increase in the maximum exercise capacity at the end of the program (105.3±32.3 vs. 121.9±37.3 W). Physical work capacity on the 2.0 mmol lactate level improved (p〈0.001) from 72.2±23.5 to 86.4±25.8 W, on the 2.5 mmol/l level (p〈0.001) from 83.5±23.2 to 97.4±26.4 W, and on the 3.0 mmol/l level (p〈0.001) from 93.1±23.0 to 106.6±26.1 W. Despite enhanced performance, heart rate remained unaltered on the 2.0, 2.5, and 3.0 mmol/l lactate level. Furthermore, ergometric performance on predefined heart rate levels was significantly (p〈0.001) increased: 85/min: from 56.0±24.1 to 65.8±24.5 W; 90/min: from 62.0±27.3 to 71.2±26 W; 95/min: from 67.2±26.4 to 77.5±27.6 W; 100/min: from 71.1±29.6 to 80.6±28.1 W; 105/min: from 69.8±26.2 to 81.9±28.2 W and 110/min: from 73.6±28.9 to 90.4±29.4 W. The results demonstrate that physical performance in patients with CAD was improved by our novel ambulatory cardiac rehabilitation program. This improvement included an increase in maximum as well as endurance work capacity; furthermore, this increase was accompanied by a decrease in resting and exercise heart rates. The results demonstrate an absolute increase of physical performance, more importantly an increase of physical performance at defined lactate levels in the presence of unchanged heart rates mediated by the rehabilitation program. Thus, this increase was independent of motivational factors in the patients and/or the investigators during the re-exercise test. On the contrary, our data demonstrate that it is based on an improvement of aerobic endurance capacity associated with a therapeutically beneficial significant decrease of heart rate for a defined workload. The effects were independent of pharmacological influences (e.g., β-receptor antagonists). These findings are of clinical importance with respect to reduction of myocardial oxygen consumption in patients with CAD.

Zusammenfassung Während eines 4wöchigen ambulanten Rehabilitationsprogramms wurden 262 KHK-Patienten, 235 Männer und 27 Frauen, Durchschnittsalter 53,6±10,2 Jahre, im Mittel 30,5±2,9 Therapiestunden im Bereich der Bewegungs- und Sporttherapie unterzogen. Inhaltlicher Schwerpunkt war ein dosiertes Ergometertraining 5mal pro Woche. Im Mittel wurden 18,4±1,8 Trainingseinheiten auf dem Ergometer absolviert. Vor und nach der Rehabilitation wurde die Leistungsfähigkeit mittels einer Belastungsuntersuchung auf dem Fahrradergometer überprüft. Auf jeder Belastungsstufe wurde neben Pulsfrequenz- und Blutdruckmessung auch eine Blutprobe aus dem hyperämisierten Ohrläppchen entnommen für die Bestimmung der Laktatkonzentration im arterialisierten Blut. Die Bestimmung der Laktatkonzentration bei ansteigender Belastung ermöglicht eine exakte Beurteilung der Ausdauerleistungsfähigkeit und dadurch eine gezielte Intensitätssteuerung während der Therapie. Weiter kann durch die Kontrolle des Laktatwertes der Therapieerfolg objektiv nachgewiesen werden. Die Ergebnisse der Vor- und Nachuntersuchung zeigten eine hochsignifikante Steigerung der maximalen Ergometerleistung von 105,3±32,3 auf 121,9±37,3 Watt. Die relative Leistungsfähigkeit wurde von 1,30±0,39 auf 1,51±0,44 Watt/kg Körpergewicht erhöht. Die mittlere Leistung bei 2,0 mmol/l Laktat im Blut wurde von 72,2±23,5 auf 86,4±25,8 Watt um 19,7%, bei 2,5 mmol/l von 83,5±23,2 auf 97,4±26,4 Watt um, 16,6% und bei 3,0 mmol/l von 93,1±23,0 auf 106,6±26,1 Watt um 14,5% jeweils hochsignifikant gesteigert. Die Herzfrequenz bei der Belastung von 2,0, 2,5 und 3,0 mmol/l Laktat blieb trotz erhöhter Wattleistung unverändert. Die Leistung für definierte Herzfrequenzwerte wurde bei allen definierten Herzfrequenzwerten (85, 90, 95, 100, 105, 110) jeweils hochsignifikant erhöht. Am deutlichsten war die Steigerung bei Herzfrequenz 110/min mit 22,8%. Die Ergebnisse zeigen, daß durch die Rehabilitation die Leistungsfähigkeit der Patienten verbessert wurde. Wie die Veränderung der erreichten Wattleistung für definierte Laktat- und Herzfrequenzwerte zeigt, basiert die beobachtete Leistungssteigerung auf einer Verbesserung der Ausdauerleistungsfähigkeit mit Ökonomisierung der Herzkreislauffunktion, verbunden mit einer für den Herzpatienten wertvollen Senkung der Herzfrequenz, und nicht lediglich auf dem psychologischen Effekt einer gesteigerten Ausbelastung auf Grund einer stärkeren Motivation des untersuchten Patietnen bzw. der Untersucher. Der Bezug auch auf die Laktatwerte ließ diesen Effekt auch unabhängig von eventueller medikamentöser Einwirkung (β-Rezeptoren-Blocker) nachweisen.

Electronic Resource

1435-1536

Springer Online Journal Archives 1860-2000

Chemistry and Pharmacology

Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics

Zusammenfassung Es wird über die Synthesen der L,L-, D,D- und D,L-Formen des 1,4-Cyclo-Phe-digly-phe-digly, des D,D-1,3-Cyclo-D-Phe-gly-D-phe-trigly sowie der Dimethyl- und Dibenzylester der 1,4-L,L-Cyclo-glu-digly-glu-digly berichtet und die Reversibilität der zum Drehungsbetrage Null für den sichtbaren Bereich der optischen Aktivität beim übergang derα-trans-trans-Formen in die ebenen polarisierten elektronenisomerenβ-Formen besprochen, eine Beobachtung, die bisher an allen 1,4 symmetrisch substituierten L-L, und D,D-Formen gemacht wurde (vgl. insbesondere die diesbezüglichen Tyrosin-Typen). Das Drehungsverhalten wird mit dem Übergang der tetraedrischen Asymmetriezentren inga-1,4-Stellung in die durch entgegengesetzte Spinanordnungen ausgezeichneten Proton-stabilisierten ebenen Biradikale an Cα 1 und Cα 4, begründet. — Die Beobachtungen an Cyclopeptiden in Verbindung mit früheren Befunden über dieα- undβ-Elektronenleitung lieferten Beiträge zur Elektronenanordnung im Diamant- und Graphitgitter, letztere haben als Prototypen aliphatischer bzw. aromatischer Verbindungen zu neuen Vorstellungen über die Verknüpfung der Elektronenkonfiguration mit der Raumstruktur, über Radikale und Onium-Verbindungen, über die C-C(Einfach)- und C=C(Doppel)-Bindung geführt. — Das Studium von SH/SS-Redox-systemen unter Beteiligung eines35-markierten cyclischen Hexapeptiddisulfids lieferte einen wichtigenBeitrag zur Frage des Peptidkettenauf- und umbaus, wie auch von Cyclopeptiden z. B. vom Typ des Cyclo-L-his-digly-L-tyr-digly; durch Polarisation erzeugte metastabile, angeregte Zustände konnten nachgewiesen werden. – Schließlich werden die Halbleitereffekte von Polypeptiden, Fermentmodellen etc. besprochen und dieβ-übergänge unter und oberhalb der Energieschwelle mit den Vorgängen in Gittern verknüpft. — Schließlich wird über dieα- undgb-Formen von Polarkomplexverbindungen sowie über polare Heterocyclen mit Dreipunktstruktur berichtet.

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