Observation and Structure Determination of an Oxide Quasicrystal Approximant.

We report on the first observation of an approximant structure to the recently discovered two-dimensional oxide quasicrystal. Using scanning tunneling microscopy, low-energy electron diffraction, and surface x-ray diffraction in combination with ab initio calculations, the atomic structure and the bonding scheme are determined. The oxide approximant follows a 3^{2}.4.3.4 Archimedean tiling. Ti atoms reside at the corners of each tiling element and are threefold coordinated to oxygen atoms. Ba atoms separate the TiO_{3} clusters, leading to a fundamental edge length of the tiling 6.7 Å.

Activation and isomerization of n-butane on sulfated zirconia model systems--an integrated study across the materials and pressure gaps.

Butane activation has been studied using three types of sulfated zirconia materials, single crystalline epitaxial films, nanocrystalline films, and powders. A surface phase diagram of zirconia in interaction with SO(3) and water was established by DFT calculations, which was verified by LEED investigations on single-crystalline films and by IR spectroscopy on powders. At high sulfate surface densities a pyrosulfate species is the prevailing structure in the dehydrated state; if such species are absent, the materials are inactive. Theory and experiment show that the pyrosulfate can react with butane to give butene, H(2)O and SO(2), hence butane can be activated via oxidative dehydrogenation. This reaction occurred on all investigated materials; however, isomerization could only be proven for powders. Transient and equilibrium adsorption measurements in a wide pressure and temperature range (isobars measured via UPS on nanocrystalline films, microcalorimetry and temporal analysis of products measurements on powders) show weak and reversible interaction of butane with a majority of sites but reactive interaction with <5 micromol g(-1) sites. Consistently, the catalysts could be poisoned by adding sodium to the surface in a ratio S/Na = 35. Future research will have to clarify what distinguishes these few sites.

Interaction of SO3 with c-ZrO2(111) films on Pt(111).

Single-crystalline sulfated c-ZrO2(111) films of the cubic (c) type have been prepared by reactive deposition of Zr onto Pt(111) in an O2 atmosphere and subsequent exposition to a SO3 atmosphere. The morphology, atomic structure, and composition have been examined by scanning tunneling microscopy, low-energy electron diffraction (LEED), Auger electron spectroscopy, and density functional theory (DFT) calculations. The clean c-ZrO2(111) films display a (2x2) surface structure. During SO3 exposure at room temperature, a clear (radical3xradical3)R30 degrees structure develops. At about 700 K, the SO3-induced (radical3xradical3)R30 degrees structure disappears and the bright (2x2) LEED pattern of the clean ZrO2 films reappears. The energies of plausible c-ZrO2(111)/SO3 structures have been examined by DFT. The (radical3xradical3)R30 degrees structure found in the experiments turned out to be the most stable one for temperatures below 700 K. At temperatures around 700 K, a disordered low coverage structure may exist, which can not be observed by conventional LEED. A comparison of cubic zirconia surfaces with the alternative tetragonal system yields similar results for the SO3 adsorption in the DFT calculations and shows that c-ZrO2 surfaces are good models for the industrial used tetragonal ZrO2 supports.

[Diagnosis and control of the course of multiple pregnancy using ultrasonic B picture technic]. / Zur Diagnose und Verlaufskontrolle von Mehrlingsschwangerschaften mit der Ultraschall-B-Bildtechnik.

In this study you find a report about the diagnosis and the control of the course of multiple pregnancy with the help of echoscopy. Out of 513 case studies, 304 female patients were examined with this method. The diagnosis can always be put practically by the experienced examiner as the optimal period for this is stated between the 20th and the 26th week of pregnancy. It is emphasized that the early detection of the multiple pregnancy is clinically uncertain. The ultrasonic control of the course of pregnancy makes it possible to find out the hypotrophy of one or both of the babies. It is also possible to measure the birth weight of the multiple babies exactly clinically. The diagnosis of the prepartal position gives an idea about the expected course of delivery. The diagnosis of a quadriple in the 22nd week of pregnancy and the corresponding ultrasonic control of the course of pregnancy is also dealt casually in short.

[Ultrasonic diagnosis in hazardous or irregular early pregnancies]. / Ultraschalldiagnostik bei der bedrohten oder gestörten Frühschwangerschaft.

747 cases of ultrasonic B-scan examinations carried out over 528 patients, in threatened or deranged stage of early gestation, are reported, and this method is hereby recommended in therapeutic check-ups of imminent abortions. Concerning cases of missed abortion it is established on the basis of individual materials and other publications that the ultrasonic technique cannot be presently substituted by any other methods. The application of ultrasonic B-scan for the diagnosis and exclusive diagnosis of hydatidiform mole, ectopic pregnancy and incomplete abortions is discussed.

[Myomas and ovarian neoplasms during pregnancy in the ultrasonic-B-picture]. / Myome und Ovarialtumoren während der Schwangerschaft im Ultraschall-B-Bild.

A report, backed up with 153 case studies of female patients, exploring the possibility of the application of ultrasonic-diagnosis in the case of a simultaneous coincidence of pregnancy and ovarian tumors and myomas is hereby forwarded. This method is suitable to differentiate ovarian tumors and myomas even during pregnancy. Cases, which are by normal clinical proceedings unintelligible, can be recognised through ultrasonic examinations. The ultrasonic course furnishes, in the ease of a normal treated tumor during pregnancy, besides parameters about the development of fetus also informations about the changes of size and position of the tumor.

[Peridural analgesia a full-term delivery of low-pain childbirth (author's transl)]. / Schmerzarme geburt durch Periduralanalgesie bei terminierter Entbindung.

Reported in this paper is a combination of "single shot" peridural analgesia with termed delivery, in the context of 100 patients. The analgesic method was applied individually to any of the women involved, depending on aggravating nociperception, all under compulsory cardiotocographic control. The results are given with reference to both objective parameters and interviews with the patients. The authors' own modification seems to be suitable for large-scale routine use.

[Diagnostic value of molecular weight related urinary protein electrophoresis in normal total protein excretion]. / Diagnostische Wertigkeit der molekulargewichtsbezogenen Harnproteinelektrophorese bei normaler Gesamteiweissausscheidung.

The electrophoresis of urinary proteins related to the molecular weight in SDS-polyacrylamide gels stood the test for the clarification of the cause of proteinurias. Also in normal excretion of the total protein the analysis of protein is reasonable after concentration of the urine. In the electrophoretic separation of 104 urinary specimens with a maximum protein content of 0.15 g/l in 44 cases a normal protein pattern was found. In 60 cases pathological patterns occurred which in their protein composition greatly corresponded to the damage within the nephron to be expected in the different clinical diagnoses. The results show that the SDS-polyacryl amide gel electrophoresis is suitable for the early recognition and differentiation of injuries of the kidneys.

[Status of ultrasound and roentgen diagnosis in prenatal detection of osteochondrodysplasias]. / Zum Stellenwert der Ultraschall- und Röntgendiagnostik bei der pränatalen Erfassung letaler Osteochondrodysplasien.

Ultrasound and X-ray investigation have a specific but complementary importance within the prenatal recording of lethal osteochondrodysplasia. In the prenatal diagnoses of thanatophoric dysplasia, asphyxiating thoracic dysplasia, chondrodysplasia punctata and achondroplasia we present our procedure for the investigation. All pregnant women are examined by ultrasound. Where the sonographical findings--according to our previous definition for the above mentioned diseases--suggest that they may be present we recommend referral to an institution with highly-specialized diagnostic possibilities for further investigation. Already in the II. trimester of pregnancy it is possible to make such group diagnoses by ultrasound. To give further specificity to the findings prenatal X-ray investigation should be done preferably in the III. trimester. The importance of confirming the diagnosis by either postnatal or postmortem X-ray investigation should be emphasized.

[Growth of the fetal thyroid gland in the 2nd half of pregnancy--biometric ultrasound studies]. / Wachstum der fetalen Schilddrüse in der II. Schwangerschaftshälfte-Sonographisch-biometrische Untersuchungen.

PURPOSE: Determination of normal values for fetal thyroid size in the 2nd half of pregnancy. METHOD: In 211 pregnant women (completed 20th to 41st week for pregnancy) without thyroid disease the fetal thyroid was measured and characterized by 5 parameters: right lobe transverse and p.a. diameter, left lobe transverse and p.a. diameter, right lobe and left lobe transverse including trachea. The level of measurement was a horizontal section of the neck with circular image of the trachea (centrally) and with the carotids as lateral limiting markers. RESULTS: The trend lines and regression coefficients of the parameters are shown in relation to week of pregnancy. The transverse diameter of both thyroid lobes including the trachea grows from 10 mm (20th week of pregnancy) to 20 mm (40th week of pregnancy). The transverse and p.a. diameters of either lobe double in the 2nd half of pregnancy. CONCLUSION: The normal values presented can help in early diagnosis of fetal thyroid hypertrophy.

[Transparent 3-D ultrasound in fetal abnormalities]. / Transparente 3D-Sonographie bei fetalen Fehlbildungen.

AIM: Evaluation of three-dimensional ultrasound (3D-ultrasound) for optimal diagnosis in fetal malformations. METHOD: The 3D-system used consists of a transmitter, position sensor and 3D-workstation. In 38 fetal malformations, verified using real-time two dimensional ultrasound, 101 volume scans were recorded to prove the following functional abilities of the system; (1) Sequential analysis of single images including volume estimation; (2) Simultaneous three plane display (longitudinal, transverse and horizontal planes); (3) Cubic sectional image; (4) Rotating or swinging volume block. RESULTS: In 85% of the cases the 3D-ultrasound clearly achieved a more reliable diagnosis in comparison to the two-dimensional images. Furthermore, the diagnostic information was considerably improved in 44% of the investigated malformations compared to the conventional two-dimensional method. The main advantages of the transparent 3D-technology are (1) Plastic global imaging of the pathological topography (fetal tumours, ureteral stenosis); (2) Exact measurement of irregular volumes (ventricle system, cerebellum); (3) Precise evaluation of fetal disproportions (triploidy, osteochondrodysplasia); (4) Detection of minor malformations. The disadvantages of the method is that all fetal movements during the scanning procedure affect adversely the three-dimensional display. CONCLUSION: The application of 3D-ultrasound in specialized prenatal units recommended.

[Utrasonic B-scan diagnosis in connection with normal prenatal care]. / Ultraschall-B-Bilddiagnostik im Rahmen der normalen Schwangerenberatung.

It is a description of a programme aimed at the inclusion of the method of Ultrasonic-B scanning diagnosis within the system of measures of cares, undertaken during pregnancy. Every fresh entry in a consultation centre, dealing with cases of pregnancy and covering a certain section of the population, undergoes echoscopy three times during the pregnancy. Investigations of the longitudinal section helps to ensure the diminishing of the deep seat of placenta with advancing stage of pregnancy. Views have been expressed about the use of echoscopy for determining the exact stage of pregnancy, for an early recognition of hypotrophy and for the calculation of the weight of the fetus. The authors recommend the integration of the method of ultrasonic diagnosis in the system of measures taken for tending the pregnant.

[Amyloidosis of the kidneys in Crohn disease]. / Amyloidose der Nieren beim Morbus Crohn.

At the instance of the variegated anamnesis of a patient with Crohn's disease the unusually rapid development of a secondary amyloidosis of the kidneys is described. Crohn's disease became manifest at the 17th year of age. The severe course of the disease of the last four years with relapsing intraabdominal abscesses and multiple formations of fistulae might be significant for the pathogenesis of the amyloidosis. If the local complications of Crohn's disease are controlled then the amyloidosis still threatens the patient's life. In case the inflammatory process could be cured the consequence would as expected be the alleviation of the amyloidosis. An additional colchicine therapy may then accelerate the process of healing. However, the nature of Crohn's disease is uncertain.

[Studies on the occurrence of Listeria in Cheese]. / Untersuchungen zum Vorkommen von Listerien im Käse.

Various outbreaks of Listeria registered in the USA and Europe after eating cheese were the motive to investigate different cheese sorts of the GDR-production on the occurrence of Listeria species. Out of 100 samples of different cheese brands 11 curdled milk cheeses (11%) showed Listeria innocua, an nonpathogenic Listeria species.

[Methods, value and limits of prenatal hearing diagnosis]. / Methode, Aussagefähigkeit und Grenzen pränataler Hördiagnostik.

An intrauterine sound test was developed for monitoring prenatal hearing disorders and evaluated concerning its efficacy and practical feasibility. The procedure is based on the fetesto capacity react upon exogenous sound stimulation. An acoustic stimulation was achieved by a noise generator placed directly on the maternal abdomen in the proximity of the fetal ear. Successful stimulation was monitored by sonographic means expressed as fetal child movements in 447 pregnant women at the end of the 26th to the 37th week of gestation. The most favourable time for an intrauterine hearing test is between the 30th and 32nd week of gestation. The quantity of amniotic liquor, placental location and pathological pregnancies influences the test results. Efficiency and limits of prenatal hearing diagnostics are discussed.