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To evaluate the association of short-term variation (STV) and Doppler parameters with adverse perinatal outcome in low-risk fetuses at term. This was a retrospective study of 1008 appropriate–for-gestational age (AGA) term fetuses. Doppler measurements [umbilical artery (UA), middle cerebral artery (MCA), and cerebroplacental ratio (CPR)] and computerized CTG (cCTG) with STV analysis were performed prior to active labor (≤ 4 cm cervical dilatation) within 72 h of delivery. The association between Doppler indices and STV values with adverse perinatal outcome was analyzed using univariate regression analysis. No significant association between Doppler parameters and the need for secondary cesarean delivery (CD) or operative vaginal delivery (OVD) was shown. Regarding fetuses delivered by CD due to fetal distress, regression analyzes revealed significantly higher UA PI MoM. However, the differences in MCA PI MoM and CPR MoM were not statistically significant. Fetuses with the need for emergency CD showed significantly higher UA PI MoM, lower MCA PI MoM and lower CPR MoM. Neonates with a 5-min Apgar score

Objectives To assess the frequency of antenatal corticosteroid (ACS) administration in cases with shortened cervical length by addition of placental alpha-microglobulin-1 (PAMG-1) testing to sonographic examination. Methods Single centre retrospective cohort study. Rate of ACS administration was compared between cases with cervical length between 15 and 25 mm and cases with positive PAMG-1 testing and cervical length between 15 and 25 mm. We evaluated the following outcome parameters: Rate of ACS administration, gestational age at delivery, time to delivery, delivery within seven days, delivery Results In total, 130 cases were included. “PAMG-1 group” consisted of 68 women, 62 cases built the “historical control group”. ACS administration was performed less frequently in the “PAMG-1 cohort” (18 (26%) vs. 46 (74%); p Conclusions Addition of biomarker testing can help to avoid unnecessary ACS administrations in women with shortened cervical length.

To evaluate the association of sonographic fetal biometry (sonographic head circumference (soHC), sonographic abdominal circumference (soAC), estimated fetal weight (EFW)) with mode of delivery and adverse perinatal outcome. Singleton pregnancies with a gestational age ≥ 37 weeks and an ultrasound examination with complete biometric parameters within 7 days before delivery were retrospectively included. The association between soHC, soAC, EFW and fetal (5-min Apgar 7, pH 7.1, neonatal intensive care unit (NICU) admission, shoulder dystocia (ShD)) and maternal (obstetric intervention (OI): caesarean or vaginal operative delivery, obstetric anal sphincter injury syndrome (OASIS), postpartum hemorrhage (pph)) adverse outcomes were analyzed using univariate and multivariate logistic regression analyses. 12 396 women were included and 3479 (28.07 %) needed an OI. Multivariate analyses demonstrated significant contributions for the prediction of OI by soHC and soAC, whereas EFW did not reach significance. The highest OR was shown for soHC (1087, p 0.001). ShD occurred in 73 (0.59 %) of the deliveries. Multivariate analyses showed that significant contributions for the prediction of ShD were provided only by soAC (OR 1460, p = 0.007). For the other maternal and neonatal adverse outcome parameters, no significant association with the biometric measurements could be demonstrated in the multivariate analyses. The overall detection rates for the prediction of adverse perinatal outcome by the different biometric parameters and EFW were poor. Obstetric management decisions should not be based solely on measurements of biometric parameters or EFW.ZIEL: Das Ziel dieser Studie war es, die Zusammenhänge zwischen sonografischer Biometrie (sonografischer Kopfumfang (soHC), Abdomenumfang (so AC), geschätztes fetales Gewicht (EFW)), Entbindungsmodus und perinatalem Outcome zu untersuchen. Es wurden retrospektiv Einlingsgraviditäten ≥ 37 Schwangerschaftswochen mit fetaler Schädellage mit einer vollständigen fetalen Biometrie innerhalb sieben Tagen vor Entbindung eingeschlossen. Die Assoziationen zwischen soHC, soAC, EFW und fetalem (5-min Apgar 7, pH 7,1, Verlegung in die Kinderklinik (NICU), Schulterdystokie (ShD)) und maternalem (geburtshilfliche Intervention (OI): Sectio caesarea (CD) oder vaginal-operative Entbindung, höhergradige Geburtsverletzung (OASIS), postpartale Hämorrhagie (pph)) Outcome wurden anhand von uni- und multivariaten logistischen Regressionsanalysen untersucht. 12 396 Frauen wurden eingeschlossen, von denen 3479 (28,07 %) per OI entbanden. Die multivariaten Analysen zeigten einen signifikanten Zusammenhang zwischen einer Entbindung per OI und dem soHC und soAC. Für EFW konnte kein signifikanter Zusammenhang nachgewiesen werden. Die höchste OR wurde für den soHC gezeigt (1087, p 0,001). Eine ShD zeigte sich in 73 Geburten (0,59 %). Die multivariaten Analysen ergaben ausschließlich für soAC (OR 1460, p = 0,007) einen signifikanten Zusammenhang zur SD. Die Untersuchung der anderen maternalen oder neonatalen Outcomeparameter blieb ohne signifikantes Ergebnis. Die Detektionsraten zur Vorhersage des perinatalen Outcomes durch die verschiedenen sonografischen Parameter waren niedrig. Das geburtshilfliche Vorgehen sollte nicht ausschließlich auf der Grundlage von sonografisch erhobenen biometrischen Parametern oder dem sonografisch geschätzten Fetalgewicht getroffen werden.

Introduction Would adolescent girls in Germany choose a different method of contraception to the combined oral contraceptive if provided with the appropriate information? Is there a need for long-acting contraception among our adolescent girls? How satisfied are female patients with the information they receive at their respective gynaecology practices, and how much do the girls know about different methods of contraception? Materials and Methods In the study “Thinking About Needs in COntraception” (TANCO), not only female patients, but also their respective gynaecologists were surveyed online about current methods of contraception, their satisfaction with these methods, and also their level of knowledge concerning the individual methods of contraception, the situation related to advice about different contraceptive options and their general satisfaction with gynaecological care. This article presents the data from the subset of adolescent girls aged 14 to 19 years (n = 2699) out of the total of 18 521 women surveyed. Results The girls surveyed were familiar with at least the name of more than five different methods of contraception (average 5.3). The doctors assumed that the respondents would know only 4.2 different methods. When asked explicitly about how the individual methods of contraception work, clear deficits became evident. This applies not only to the entire population of respondents, but also the users of the respective contraceptive method. In addition, a strong interest in long-acting contraception emerged from the survey, particularly among young women. Discussion The data from the TANCO study reveal a clear discrepancy between the existing contraception almost exclusively in the form of the contraceptive pill and the contraceptive options considered by adolescent girls if they are thoroughly informed. The need for education into alternatives to the pill is high, as is the willingness to use such alternatives after receiving information – much higher than the figures suggested by the gynaecologists.

Objective The aim of this study was to assess the influence of premature rupture of membranes (PROM) on the induction of labor. Material and Method This historical cohort study analyzed 1861 inductions of labor at term using misoprostol which occurred between 2010 and 2015. Exclusion criteria included intrauterine fetal death, previous cesarean section, and fetal structural or chromosomal anomalies. Induction of labor for PROM (PROM group) was compared to induction for other indications (no-PROM group); the primary outcome measure was the cesarean section rate. Results The cesarean section rate for the PROM group was significantly lower (21.9% vs. 26.3%, p = 0.029). The induction-to-delivery interval was shorter (mean: 972 [854 – 6734] min vs. 1741 [97 – 10 834] min, p Conclusion Premature rupture of membranes significantly affects various outcome measures when delivery is induced, particularly the induction-to-delivery interval.

The aim of this study was to determine the extent to which women’s choice of contraceptive method depends on the advice received from their gynecologist and whether more intensive counseling might lead to more frequent use of long-acting reversible contraception (LARC). A total of 1089 physicians and 18,521 women responded to 32 or 37 questions, respectively, using an online questionnaire. The women were asked about their current use of contraceptive methods, the extent of their satisfaction with them, their satisfaction with the counseling they had received, and whether they wanted to have more information about contraception. The physicians were similarly asked which contraceptive methods were being used, how satisfied with them they were, how they would assess their patients’ satisfaction with them, and whether the women wanted to have more information. The results showed that 61% of the women were using oral contraceptives, and a total of only 9% were using behavior-independent long-term contraceptive methods. However, 60% of the women stated that long-term contraception would be an option for them if they had more information about it. Gynecologists underestimated this figure, at only 18%. Whereas 66% of the gynecologists believed that their patients never forgot to take the pill, nearly, half of the women stated that they had forgotten it at least once during the previous 3 months. The small number of women who use long-term contraception is in clear contrast to the fact that many women want to have a very safe but also behavior-independent method.

To evaluate the longitudinal pattern of fetal heart rate short term variation (STV) and Doppler indices and their correlation to each other in severe growth restricted (IUGR) fetuses. In this retrospective study, pregnancies with a birth weight below the 10th percentile, born between 24 and 34 gestational weeks with serial Doppler measurements in combination with a computerized CTG (cCTG) with calculated STV were included. Longitudinal changes of both Doppler indices and STV values were evaluated with generalized additive models, adjusted for gestational age and the individual. For all measurements the frequency of abnormal values with regard to the time interval before delivery and Pearson correlations between Doppler indices and STV values were calculated. 41 fetuses with a total of 1413 observations were included. Over the course of the whole study period, regression analyses showed no significant change of STV values (p = 0.38). Only on the day of delivery, a prominent decrease was observed (mean STV d28-22: 7.97 vs. mean STV on day 0: 6.8). Doppler indices of UA and MCA showed a continuous, significant deterioration starting about three weeks prior to delivery (p = 0.007; UA and p 0.001, MCA). Correlation between any Doppler index and STV values was poor. Fetal heart rate STV does not deteriorate continuously. Therefore, cCTG monitoring should be performed at least daily in these high-risk fetuses. Doppler indices of umbilical artery (UA) and middle cerebral artery (MCA), however, showed continuous deterioration starting about 3 weeks prior to delivery.ZIEL: Analyse des longitudinalen Verlaufs der Kurzzeitvariation der fetalen Herzfrequenz (STV) und der Dopplerindizes und deren Korrelation zueinander bei Feten mit früh einsetzender Wachstumsrestriktion (IUGR). In diese retrospektive Studie wurden Einlings-Schwangerschaften eingeschlossen, welche ein Geburtsgewicht unterhalb der 10. Perzentile aufwiesen und zwischen 24 + 0 und 34 + 0 SSW entbunden wurden. Bei den eingeschlossenen Schwangerschaften fanden serielle Untersuchungen der Dopplerparameter, kombiniert mit der Erhebung der STV durch computerisierte CTGs (cCTG), statt. Die Analyse des longitudinalen Verlaufs der Dopplerparameter und der STV wurde mittels eines generalisierten additiven Modells durchgeführt. Für alle Messungen wurde die Häufigkeit pathologischer Untersuchungsbefunde im Hinblick auf das Zeitintervall zwischen Messung und Geburtszeitpunkt bestimmt. Zusätzlich wurden Pearson-Korrelationen zwischen Dopplerindizes und der STV berechnet. 41 Feten mit insgesamt 1413 Untersuchungen wurden eingeschlossen. Über den gesamten Beobachtungszeitraum zeigte sich in der Regressionsanalyse keine signifikante Veränderung der STV (p = 0,38). Einzig am Entbindungstag ließ sich ein deutlicher Abfall der STV nachweisen (mittlere STV d28-22: 7,97 vs. mittlere STV d0: 6,80). Die Auswertung der Dopplerindizes der UA und MCA zeigte eine stetige Verschlechterung der erhobenen Werte, beginnend ca. 3 Wochen vor Entbindung (p = 0,007, UA und p 0,001, MCA). Eine signifikante Korrelation zwischen einzelnen Dopplerindizes einerseits und STV andererseits bestand nicht, unabhängig von der Zeitdifferenz zwischen den jeweiligen Untersuchungen. Die fetalen STV-Werte zeigten ausschließlich am Entbindungstag einen signifikanten Abfall, sodass bei diesem Risikokollektiv mindestens täglich eine cCTG-Untersuchung durchgeführt werden sollte. Dopplerparameter von A. umbilicalis (UA) und A. cerebri media (MCA) jedoch zeigten bereits 3 Wochen vor Entbindung eine kontinuierliche Verschlechterung.

Aim The best time to commence cervical ripening with a balloon catheter is unknown. The aim of this study was to evaluate whether application of a balloon catheter in the morning or in the evening is better when sequential prostaglandin application is planned. Methods This multicenter historical cohort study included 415 women with an unfavorable cervix undergoing labor induction at term. Labor was induced with a double-balloon catheter and the sequential use of oral misoprostol if necessary. The balloon catheter was placed in the morning group between 02:00–15:00 and in the evening group between 15:00–02:00. The primary outcome measure was the cesarean section rate. Secondary outcome measures included failed labor induction (no vaginal delivery within 72 h). Results The cesarean section rate did not differ between the groups (morning 26.9%, evening 24.3%; P = 0.5553); however, more women in the morning group did not deliver within 72 h (8.8% vs 3.1%; P = 0.0138). In nulliparous women, labor induction failed more often in the morning group (12% vs. 4%, P = 0.043). In parous women, the induction-to-delivery interval was longer in the morning group (1756 vs. 1349 min; P = 0.046), and there were fewer deliveries within 24 h (35% vs. 56%, P = 0.016). Conclusions When sequential use of a double-balloon catheter and oral misoprostol for labor induction is planned, the preferable time for catheter placement is in the evening. This resulted in fewer failed inductions in nulliparous women and a shorter induction-to-delivery interval and more deliveries within 24 h in parous women.

Der verantwortungsvolle Umgang mit Patientinnen in der Kinder- und Jugendgynakologie bedarf eines speziellen Wissens uber die embryonale Entwicklung des inneren und auseren Genitales, uber Besonderheiten in den einzelnen Hormonphasen und Ablaufe in der Pubertat mit ihren Normvarianten. Die haufigste Diagnose des Kleinkindes ist die Labiensynechie, eine Verklebung der kleinen Schamlippen, die einfach zu diagnostizieren ist. Haufigster Vorstellungsgrund im Kindesalter ist die Vulvovaginitis, bei deren Diagnostik die verschiedenen Hormonphasen und mogliche Differenzialdiagnosen wichtig sind. Bei Jugendlichen sind Blutungsstorungen ein wichtiger Vorstellungsgrund. Hier kann durch die Erhebung der Pubertatsstadien einfach auf Ursachen geschlossen werden (primare/sekundare/tertiare Ovarialinsuffizienz). Bei Madchen mit primarer Amenorrho, normal abgelaufener Pubertatsentwicklung und Einsetzen der Thelarche vor > 2,5 Jahren muss an eine genitale Fehlbildung gedacht werden.

Introduction Preeclampsia is a hypertensive, gestational disease, which is still the leading cause of pregnancy related morbidity and mortality. The impairment of placental angiogenesis and vascularization is discussed to be of etiopathologic relevance. Deytrosination and tyrosination of α-tubulin is important for the stability and dynamics of microtubules. An increase of α-tubulin detyrosination leads to microtubule stabilization, which is an essential prerequisite for physiologic vascular tube morphogenesis during angiogenesis. So far, little is known about the specific localization of detyrosinated (detyr) and tyrosinated (tyr) tubulin in the placenta and its relevance for preeclampsia. Methods Placental expression of detyr- and tyr-tubulin was analyzed by immunohistochemistry, immunofluorescence and western blot. For western blot quantification we used biopsies from healthy placentas (n = 21) and placentas from pregnancies complicated with small for gestational age (n = 5), preeclampsia (n = 5) or both (n = 5). Results Specific placental localization of detyr-tubulin was detected in the fetal endothelial cells of the placenta. Villous and extravillous trophoblasts as well as villous stroma cells were tyr-tubulin positive. Detyr-tubulin protein expression was significantly decreased in placentas complicated by preeclampsia. Conclusions In summary, we report an accumulation of detyr-tubulin in villous vessels of the placenta and a significantly reduced level of detyr-tubulin in placental biopsies of preeclampsia cases. The reduction of placental detyr-tubulin in preeclampsia could suggest a deficit in villous vascular plasticity and might be associated with the impaired arborization of the disease.

Fragestellung: Kann die Leistung von Studierenden in der Klausur zur Hauptvorlesung durch das Angebot von CME-Fragen zu den einzelnen Themen der Veranstaltung gesteigert werden? Methodik: Fur diese prospektive randomisierte Untersuchung wurden die vier Semesterkohorten (von SoSe 2013 bis WiSe 2014/2015) jeweils in zwei Gruppen geteilt. Beide Gruppen erhielten zeitgleich Zugang zu den Folien der einzelnen Lehrveranstaltungen. Lediglich einer Gruppe wurden zusatzlich jeweils 3 CME-Fragen zu den Themen angeboten. Die Fragen konnten im Verlauf des Semesters mehrmals bearbeitet werden. Das Ergebnis der Beantwortung spielte keine Rolle fur die Benotung der Klausur. Es wurde ausgewertet, ob die Kohorte mit den CME-Fragen in der Hauptklausur besser abschnitt. Ergebnis: Die Gruppe der Studierenden mit CME-Fragen schnitt durchschnittlich um 2,2 Punkte (von moglichen 40 Punkten) besser ab. Dies stellte sich als signifikant heraus. Dieser Effekt nivellierte sich im Laufe der Semester. Schlussfolgerung: Das zusatzliche Angebot von CME-Fragen begleitend zur Hauptvorlesung in unserem Fach kann zu einer intensiveren Vorbereitung und zu einem besseren Abschneiden der Studierenden in der Klausur fuhren. Die Abflachung des Effektes uber die Semester kann eventuell durch eine Verbreitung der CME-Fragen in sozialen Netzwerken erklart werden.

Introduction: Endometriosis is a heterogeneous disease characterized by a range of different presentations. It is usually diagnosed when patients present with pain and/or infertility, but it has also been diagnosed in asymptomatic patients. Because of the different diagnostic approaches and diverse therapies, time to diagnosis can vary considerably and the definitive diagnosis may be delayed, with some cases not being diagnosed for several years. Endometriosis patients have many unmet needs. A systematic registration and follow-up of endometriosis patients could be useful to obtain an insight into the course of the disease. The validation of biomarkers could contribute to the development of diagnostic and predictive tests which could help select patients for surgical assessment earlier and offer better predictions about patients who might benefit from medical, surgical or other interventions. The aim is also to obtain a better understanding of the etiology, pathogenesis and progression of the disease. Material and Methods: To do this, an online multicenter documentation system was introduced to facilitate the establishment of a prospective multicenter case-control study, the IEEP (International Endometriosis Evaluation Program) study. We report here on the first 696 patients with endometriosis included in the program between June 2013 and June 2015. Results: A documentation system was created, and the structure and course of the study were mapped out with regard to data collection and the collection of biomaterials. Conclusion: The documentation system permits the history and clinical data of patients with endometriosis to be recorded. The IEEP combines this information with biomaterials and uses it for scientific studies. The recorded data can also be used to evaluate clinical quality control measures such as the certification parameters used by the EEL (European Endometriosis League) to assess certified endometriosis centers.

Selective area growth (SAG) technology has been added to an established InP monolithic integration platform to fabricate arrays of multi-wavelength distributed feedback (DFB) lasers. The local epitaxy growth rate is controlled by the SiO 2 mask width, and different quantum well (QW) thicknesses can be obtained in one run. The laser wavelengths span from 1447 nm to 1602 nm. The DFB lasers may include amplifying sections at the front and/or rear side. Output power up to 18 mW is achieved. This technology opens up possibilities to integrate various passive and active components such as lasers, modulators, detectors with different operating wavelengths monolithically on one wafer with less regrowth steps and reduced fabrication complexity.

An ultra-fine eutectic structure has been obtained in the Ti 70.5 Fe 29.5 binary alloy by slow cooling from the melt through arc melting and cold crucible rod casting. The addition of 3.85 at.% Sn to the binary Ti–Fe alloy induces a change of the morphology of the eutectic and increases the volume fraction of the FeTi ( Pm 3 m ) phase. A significant improvement of the plastic deformability of the ternary alloy has been observed under uniaxial compressive loading resulting in 16% strain to failure compared to 3.4% for binary Ti 70.5 Fe 29.5 . The morphology of the eutectic colonies, their refinement and supersaturation of the β-Ti phase are crucial factors for improving the ductility of the ultra-fine eutectic alloys.

The deformation behavior of multicomponent Ti66Cu8Ni4.8Sn7.2Nb14 composite containing primary dendrites embedded in a nanoeutectic matrix was studied under uniaxial compression. The evolution of slip and shear bands has been investigated at various stages of deformation. This type of advanced composite not only displays a high compressive plasticity of 31.8%, but also exhibits high fracture strength of approximate to 2.02 GPa (true fracture strength 1.38 GPa). Pronounced work hardening was observed after yielding. The surface deformation morphology reveals that the work hardening behavior of the composite is related to the plastic deformation of the dendritic phase through slip bands and the interaction of shear bands in the nanostructured matrix with the hardened dendrites. The nucleation of shear band occurs at a certain amount (8%) of plastic deformation at the dendrite-nanoeutectic matrix interface. The final stage of compression proceeds through passing of the shear bands through the work-hardened dendrites into the nanoeutectic matrix, whereby the propagation of the shear bands in the matrix is retarded by the nanoscale phases. (C) 2006 Elsevier B.V. All rights reserved.

Investigation of the microstructure of a compressed Ti66.1Cu8Ni4.8Sn7.2Nb13.9 nanostructure–dendrite composite reveals that the deformed bcc β-Ti dendrites form a stepped morphology at the interfaces between the individual dendrites and the nanostructured matrix of hcp α-Ti and bct Ti2Cu phases. Furthermore, there is a unique stained contrast during the propagation and the interaction of the shear bands in the dendrites indicating a local structural change near to the apex of the shear bands in the dendrite. In contrast, the shear bands pass through coherent grain boundaries between the hcp α-Ti and the bct Ti2Cu phases of the nanostructured matrix.

Granivory can play a pivotal role in influencing regeneration, colonization as well as abundance and distribution of plants. Due to their high abundance, nutrient content and longevity, seeds are an important food source for many animals. Among insects, carabid beetles consume substantial numbers of seeds and are thought to be responsible for a significant amount of seed loss. However, the processes that govern which seeds are eaten and are therefore prevented from entering the seedbank are poorly understood. Here, we assess if DNA-based diet analysis allows tracking the consumption of seeds by carabids. Adult individuals ofHarpalus rufipeswere fed with seeds ofTaraxacum officinaleandLolium perenneallowing them to digest for up to 3 days. Regurgitates were tested for the DNA of ingested seeds at eight different time points post-feeding using general and species-specific plant primers. The detection of seed DNA decreased with digestion time for both seed species, albeit in a species-specific manner. Significant differences in overall DNA detection rates were found with the general plant primers but not with the species-specific primers. This can have implications for the interpretation of trophic data derived from next-generation sequencing, which is based on the application of general primers. Our findings demonstrate that seed predation by carabids can be tracked, molecularly, on a species-specific level, providing a new way to unravel the mechanisms underlying in-field diet choice in granivores.

Usually, bulk metallic glasses exhibit strength values superior to conventional crystalline alloys, often combined with a large elastic limit and rather low Young's modulus. This combination of properties renders such alloys quite unique when compared to commercial materials. However, the major drawback for engineering applications is their limited room temperature ductility and toughness due to the localized deformation processes linked to shear banding, where high plastic deformation is accumulated in a very narrow region without contributing to macroscopic deformation, work hardening or yielding. In this work we report on a new class of metallic glass in a simple Cu-base alloy. Addition of 5 at.% Al increases the glass-forming ability of binary Cu50Zr50. The resulting Cu47.5Zr47.5Al5 glass exhibits high strength (2265 MPa) together with large room temperature ductility up to 18%. After yielding a strong increase in the flow stress is observed during deformation. The structure of the metallic glass exhibits atomic-scale heterogeneities that enable easy nucleation and continuous multiplication of shear bands. The interaction and intersection of shear bands increases the flow stress of the material with further deformation, leading to a 'work hardening'-like behavior and yields a continuous rotation of the shear angle up to fracture resulting in a high compressive ductility. (c) 2006 Elsevier Ltd. All rights reserved.

Ni70Nb30 metallic glass powders were prepared by mechanical alloying and subsequently combined with Al in order to form a metallic glass particle-reinforced Al-based metal matrix composite sintered below the melting temperature of Al by using the powder metallurgy method. The Young's modulus, yield strength and ultimate strength are all higher than for single-phase pure Al. (c) 2006 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Microstructural investigation of a deformed Ti66.1Cu8Ni4.8Sn7.2Nb13.9 nanostructure-dendrite composite using transmission electron microscopy (TEM) reveals heterogeneous propagation and interaction of the shear bands, depending on the geometry of the interfaces between the nanostructured matrix and dendrites. The geometrical effect on the propagation and interaction of the shear bands is presented by the different morphology of the interfaces i.e. stepped and smooth interfaces suggesting a different amount of accumulated shear strains at the interfaces between the nanostructured matrix and the dendrites. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

This paper evaluates the performance of the stratospheric ozone analyses delivered in near real time by the MACC (Monitoring Atmospheric Composition and Climate) project during the 3 year period between September 2009 and September 2012. Ozone analyses produced by four different chemistry transport models and data assimilation techniques are examined: the ECMWF Integrated Forecast System (IFS) coupled to MOZART-3 (IFS-MOZART), the BIRA-IASB Belgian Assimilation System for Chemical ObsErvations (BASCOE), the DLR/RIU Synoptic Analysis of Chemical Constituents by Advanced Data Assimilation (SACADA), and the KNMI Data Assimilation Model based on Transport Model version 3 (TM3DAM). The assimilated satellite ozone retrievals differed for each system: SACADA and TM3DAM assimilated only total ozone observations, BASCOE assimilated profiles for ozone and some related species, while IFS-MOZART assimilated both types of ozone observations. The stratospheric ozone analyses are compared to independent ozone observations from ground-based instruments, ozone sondes and the ACE-FTS (Atmospheric Chemistry Experiment – Fourier Transform Spectrometer) satellite instrument. All analyses show total column values which are generally in good agreement with groundbased observations (biases 50%) for ozone in the lower stratosphere in the Tropics and in the Antarctic, especially during ozone hole conditions. This study shows that ozone analyses with realistic total ozone column densities do not necessarily yield good agreement with the observed ozone profiles. It also shows the large benefit obtained from the assimilation of a single limb-scanning instrument (Aura MLS) with a high density of observations. Hence even state-of-the-art models of stratospheric chemistry still require the assimilation of limb observations for a correct representation of the vertical distribution of ozone in the stratosphere.

Atomic defects have been studied in Al–Pd–Mn and Zn–Mg–Ho icosahedral quasicrystals by means of positron annihilation spectroscopy and time-differential dilatometry. In addition, the first in situ positron lifetime measurements on Al–Pd–Mn quasicrystals at high temperatures are performed. In the time-differential dilatometry studies, after fast cooling at high temperatures an anomalous time-dependent isothermal expansion of the specimen was observed. If this length change is attributed to atomic defects the defect formation and the migration can be studied. Positron lifetimes could be derived for icosahedral Al 70.2 Pd 21.3 Mn 8.5 and icosahedral Zn 61 Mg 28 Ho 11 with 214 and 212 ps, respectively. These lifetimes are ascribed to structural vacancies in these quasicrystalline systems, which are supported, by electron irradiation and long-term annealing experiments.

In order to better understand the electronic barriers at the metal contacts of organic light emitting devices (OLEDs), we investigated interfaces of thin films of endcapped sexithiophene (EC6T) with metal contacts by Ultraviolet and X-ray Photoelectron Spectroscopy (UPS/XPS). We compare the interface of an EC6T film deposited on an Ag(111) surface and the interface obtained by deposition of Al on an EC6T film. The two situations differ in so far as a strong chemical reaction and diffusion of Al into the EC6T film occurs in the latter. For the EC6T/Ag(111) interface we derive the existence of an interface dipole leading to a “band-offset” directly at the interface. For Al/EC6T, the data suggest a common vacuum level for the reacted molecules and the Al. The band-offset is determined as 1.7 eV. These results are discussed in context with capacity–voltage measurements performed on Al/EC6T/indium–tin-oxide OLEDs.

For studying atomic vacancies in quasicrystals the specific technique of positron annihilation spectroscopy has been employed. In quasicrystals and approximants of the Al–Pd–Mn and the Zn–Mg–Ho systems structural vacancies in the concentration range of 10 −3 have been observed. We perform the first in-situ measurements of the positron lifetime at high temperatures, where the formation of thermal vacancies in i-Al 70.2 Pd 21.3 Mn 8.5 can be observed directly. The annealing behavior of quenched-in vacancies, which coincide with the data from earlier time differential dilatometry studies after fast temperature changes, gives access to the vacancy migration properties and kinetics in quasicrystals. From the coincident measurement of the Doppler broadening of the positron-electron annihilation photon line at ambient temperatures, we deduce that the vacancies observed in i-Al 70.2 Pd 21.3 Mn 8.5 are predominantly located in an Al rich environment. Since high-temperature processes such as diffusion, plasticity and structural phase transformations, are strongly influenced by thermal vacancies and their kinetics, the present experiments can provide information on these processes.

Usually, monolithic bulk metallic glasses undergo inhomogeneous plastic deformation and exhibit poor ductility (< 1%) at room temperature. We present a new class of bulk metallic glass, which exhibits high strength of up to 2265 MPa together with extensive "work hardening" and large ductility of 18%. Significant increase in the flow stress was observed during deformation. The "work-hardening" capability and ductility of this class of metallic glass is attributed to a unique structure correlated with atomic-scale inhomogeneity, leading to an inherent capability of extensive shear band formation, interactions, and multiplication of shear bands.

In the present paper we succeeded in studying structural phase transitions from an atomistic point of view by positron annihilation Doppler broadening. This differs and is complementary to conventionally used diffraction experiments with large coherence lengths. In the exemplary case of the 1140 K order-disorder transition in decagonal Al71.5Ni14Co14.5 quasicrystals the importance of this atomistic approach and its wide scope of application is demonstrated.