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Insights into the structure of surface oxides on Zn–coated press–hardened steel (PHS) are indispensable for further processing like welding or adhesive bonding. The main oxide on top of galvanized steel is Al2O3 from the primary galvanizing process. This oxide is strongly altered during final austenitization annealing before hot–forming resp. press–hardening, depending on the annealing time. Four different steel grades are investigated, whereupon two are standard galvanized and the other two are galvannealed. For both coatings, we can show that the main oxides after austenitization heat treatment are native ZnO and the initial Al2O3. Our results indicate that the main alloying component Mn forms (Mn,Zn)Mn2O4 spinel, which also contains traces of Fe and is embedded in the upper ZnO layer. Also noticeable was a varying, nanometer thick Cr enrichment at the initial Al2O3 layer depending on the availability of Cr in the steel alloy. Small precipitates of further alloy elements can be found at this (Cr,Al)2O3 layer. Further experiments with time–of–flight secondary ion mass spectrometry attached to a helium ion microscope allowed to reliably distinguish between ZnO and Zn(OH)2, which are both present in the oxide layers. All specimen show high local differences related to skin–passing prior to final heat treatment. This is especially the case for shorter annealed specimen, where thermodynamic equilibrium is not yet reached.

Effects of steel alloying agents on the formation of the surface oxide layer of galvanized press hardened steel after austenitization annealing were examined with various advanced microscopy and spectroscopy techniques. The main oxides on top of the original thin Al2O3 layer, originating from the primary galvanizing process, are identified as ZnO and (Mn,Zn)Mn2O4 spinel. For some of the investigated steel alloys, a non-uniform, several nanometer thick Cr-enriched additional film was found at the Al2O3 layer. At a sufficiently high concentration, Cr can act as a substitute for Al during annealing, strengthening and regenerating the original Al2O3 layer with Cr2O3. Further analysis with secondary ion mass spectrometry allowed a reliable distinction between ZnO and Zn(OH)2.

Zink-coated press hardened steel (PHS) is due to its extremely high tensile strength and its excellent corrosive protection indispensable for structural elements in modern automotive applications. Different studies clarify the resulting microstructure of the Zn-coating after press hardening [1] of such steel parts. Also, the uppermost surface oxide layer, which can be influenced by steel matrix alloy elements, has a significant impact on the processing properties like coating or welding. In this study, we investigated these surface oxide layers for alloy compositions of four different PHS systems with scanning and conventional transmission electron microscopy (TEM), Auger electron spectroscopy (AES) and helium ion microscopy (HIM). The complex and porous oxide-layers were stabilized by epoxy before the preparation of cross-sections and TEM-lamellae by focused ion beam milling. The main oxides on top of the original thin Al2O3 layer, originating from the primary galvanizing process, could be determined with energy dispersive X-ray spectroscopy (EDX), selected area diffraction and AES as Zn-oxides and (Mn,Zn)Mn2O4 spinel (Fig. 1a). Also noticeable was a varying, nanometre thick Cr enrichment at this Al2O3 layer (Fig. 1b), which depends strongly on the steel alloy. Further experiments with secondary mass spectrometry (ToF-SIMS) attached to a HIM [2] allowed reliable distinguishing between ZnO and Zn(OH)2 (Fig. 2c), which are both present in our oxide layers. Thus, we could show an influence of different steel alloy elements on the final oxide structure after press hardening. The formation of spinel is triggered by Mn, which is transported with the Zn above the Al2O3 layer, which itself is a trap for Cr, leading to a coverage of it with Cr-oxides. Figure 1. a) AES Mapping. b) STEM-EDX Mapping c) ToF-SIMS Mapping References: [1] H. Järvinen et al, Surface and Coatings Technology 352 (2018), 378-391. [2] N. Klingner et al, Ultramicroscopy 198 (2019), 10-17. The financial support by the Austrian Federal Ministry for Digital and Economic Affairs and the National Foundation for Research, Technology and Development in the frame of the CDL for nanoscale phase transformations is gratefully acknowledged.

Under cloud free conditions, the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) provides measurements of spectrally resolved limb radiances down to the upper troposphere. These are used to infer global distributions of mixing ratios of atmospheric constituents in the upper troposphere and the stratosphere. From 21 October to 12 November 2003, MIPAS observed enhanced amounts of upper tropospheric C2H6 (up to about 400 pptv) and ozone (up to about 80 ppbv). The absolute values of C2H6, however, may be systematically low by about 30% due to uncertainties of the spectroscopic data used. By means of trajectory calculations, the enhancements observed in the southern hemisphere are, at least partly, attributed to a biomass burning plume, which covers wide parts of the Southern hemisphere, from South America, the Atlantic Ocean, Africa, the Indian Ocean to Australia. The chemical composition of the part of the plume-like pollution belt associated with South American fires, where rainforest burning is predominant appears different from the part of the plume associated with southern African savanna burning. In particular, African savanna fires lead to a larger ozone enhancement than equatorial American fires. In this analysis, MIPAS observations of high ozone were disregarded where low CFC-11 (below 245 pptv) was observed, because this hints at a stratospheric component in the measured signal. Different type of vegetation burning (flaming versus smouldering combustion) has been identified as a candidate explanation for the different plume compositions.

Durch die Gewinnung einer Samenprobe in Medium erhöht sich der Anteil der antikörperfreien Spermatozoen in Samenproben mit antikörperbehafteten Spermien und erhöht somit die Fertilisationsrate in vitro. Das Ziel dieser Studie war es zu untersuchen, ob sich dieser Verdünnungseffekt auch günstig auf Ejakulate mit einem Oligoasthenoterato-zoospermie (OAT)-Syndrom auswirkt, in denen oft eine große Anzahl an Bakterien und Zelldetritus den Spermien anhaftet. Die Zugabe von Medium vor der Verflüssigung könnte das Anhaften von Bakterien und Detritus an der Spermienoberfläche verhindern und somit zu besseren Befruchtungschancen führen. 173 Patienten, die in einem Probespermiogramm oder einem früheren IVF-Zyklus ein schweres OAT-Syndrom zeigten, wurden in diese retrospektive Studie eingeschlossen. Alle Patienten durchliefen 1997 und 1998 das ICSI-ET (Intrazytoplasmatische Spermieninjektion und Embryotransfer) Programm an der Universität Würzburg. 118 Patienten gewannen ihre Samenprobe in leere, sterile Gefäße (Gruppe A) und 55 Patienten ejakulierten in 20 ml Hepes gepuffertes Ham's F-10-Medium, das mit 10 % HSA (humanes Serumalbumin) versetzt war (Gruppe B). Das Alter der Patientinnen und der Ehemänner, die Ejakulatparameter und die Anzahl der transferierten Embryonen war in beiden Gruppen vergleichbar. Alle Ejakulate wurden gemäß WHO-Kriterien klassifiziert. Nach Gewinnung der Samenprobe in Medium wurde das Ejakulat der Gruppe B für 30 min inkubiert, anschließend zentrifugiert und mit einer Swim-up-Technik aufbereitet. Die Ejakulate der Gruppe A wurden ebenfalls mit einer Swim-up-Technik präpariert. Bei den 173 ICSI-Zyklen konnten durchschnittlich 9,3 Eizellen gewonnen werden. Die mediane Fertilisationsrate (FR) lag bei 83,3 % und unterschied sich in den Gruppen A (FR = 87,5 %) und B (FR = 77,8 %) nicht signifikant. Es wurden im Mittel 2,7 Embryonen transferiert. 27 von 118 Patientinnen der Gruppe A konzipierten, was zu einer klinischen Schwangerschaftsrate von 22,9 % führte. In Gruppe B konnte eine Schwangerschaftsrate von 34,5 % (19 Konzeptionen von 55 Patientinnen) erzielt werden (n.s.). Die Ergebnisse zeigen, daß die Vorlage von Hepes gepuffertem Ham's F-10-Medium bei der Ejakulation bei Patienten mit Oligoasthenoteratozoospermie zu einer deutlichen, wenn auch nicht statistisch signifikanten Erhöhung der klinischen Schwangerschaftsrate führen kann. Es ist eine einfache und effiziente Methode, die bei allen Patienten mit schwerer männlicher Subfertilität Anwendung finden könnte.

During several periods since 2005 the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on Envisat has performed observations dedicated to the region of the upper troposphere/lower stratosphere (UTLS). For the duration of November/December 2005 global distributions of temperature and several trace gases from MIPAS UTLS-1 mode measurements have been retrieved using the IMK/IAA (Institut für Meteorologie und Klimaforschung/ Instituto de Astrof´ısica de Andalucía) scientific processor. In the UTLS region a vertical resolution of 3 km for temperaure, 3 to 4 km for H2O, 2.5 to 3 km for O3, 3.5 km for HNO3 and 3.5 to 2.5 km for N2O has been achieved. The retrieved temperature, H2O, O3, HNO3, N2O, and relative humidity over ice are intercompared with the Microwave Limb Sounder (MLS/Aura) v2.2 data in the pressure range 316 to 0.68 hPa, 316 to 0.68 hPa, 215 to 0.68 hPa, 215 to 3.16 hPa, 100 to 1 hPa and 316 to 10 hPa, respectively. In general, MIPAS and MLS temperatures are biased within ±4K over the whole pressure and latitude range. Systematic, latitude-independent differences of −2 to −4K (MIPASMLS) at 121 hPa are explained by previously observed biases in the MLS v2.2 temperature retrievals. Temperature differences of −4K up to 12K above 10.0 hPa are present both in MIPAS and MLS with respect to ECMWF (European Centre for Medium-Range Weather Forecasts) and are likely due to deficiencies of the ECMWF analysis data. MIPAS and MLS stratospheric volume mixing ratios (vmr) of H2O are biased within ±1 ppmv, with indication of oscillations between 146 and 26 hPa in the MLS dataset. Tropical upper tropospheric values of relative humidity over ice measured by the two instruments differ by ±20% in the pressure range ~146 to 68 hPa. These differences are mainly caused by the MLS temperature biases. Ozone mixing ratios agree within 0.5 ppmv (10 to 20%) between 68 and 14 hPa. At pressures smaller than 10 hPa, MIPAS O3 vmr are higher than MLS by an average of 0.5 ppmv (10%). General agreement between MIPAS and MLS HNO3 is within the range of −1.0 (−10%) to 1.0 ppbv (20%). MIPAS HNO3 is 1.0 ppbv (10%) higher compared to MLS between 46 hPa and 10 hPa over the Northern Hemisphere. Over the tropics at 31.6 hPaMLS shows a low bias of more than 1 ppbv (>50%). In general, MIPAS and MLS N2Ovmr agree within 20 to 40 ppbv (20 to 40%). Differences in the range between 100 to 21 hPa are attributed to a known 20% positive bias in MIPAS N2O data.

In order to improve the ovarian response to exogenous gonadotropins and to reduce the risk of the ovarian hyperstimulation syndrome and of multiple pregnancies, human menopausal gonadotropin (hMG) was administered by continuous pulsatile subcutaneous (s.c.) infusion via a portable pump. The effectiveness of pulsatile hMG treatment was first demonstrated in a control group comprising 7 females with regular ovulatory cycles, who underwent gonadotropin ovarian superovulation and subsequent IVF/GIFT procedures for tubal or male factor. All pulsatile s.c. hMG cycles were ovulatory and one clinical pregnancy was achieved. In this group, ovarian response was similar following intramuscular (i.m.) and pulsatile s.c. hMG therapy, with a marked reduction of preovulatory serum levels of oestradiol in the pulsatile s.c. hMG cycles. In a prospective study, 11 patients with overt polycystic ovary syndrome (PCO) who failed to ovulate in response to clomiphene, received i.m. hMG ovarian superovulation treatment in 19 cycles and pulsatile s.c. hMG in 21 cycles. Following i.m. hMG treatment, only 10 cycles were ovulatory; 7 cycles had to be cancelled for impending ovarian hyperstimulation syndrome. Following pulsatile s.c. hMG treatment, 15 cycles were ovulatory, only 3 treatment cycles had to be disrupted for multifollicular ovarian response. Both modes of treatment were similar in terms of requirement of hMG ampoules, number of preovulatory follicles, preovulatory serum levels of oestradiol and duration of the preovulatory oestradiol rise. The total duration of hMG treatment was significantly increased following pulsatile s.c. hMG. It is concluded, that in overt PCO syndrome, continuous pulsatile s.c. administration of hMG is an effective method to induce follicular maturation and to achieve ovulations.(ABSTRACT TRUNCATED AT 250 WORDS)

International audience; The Fourier transform spectrometer MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) on Envisat measures infrared emission of the Earth's atmosphere in a limb viewing mode. High spectral resolution measurements of MIPAS are sensitive to formaldehyde from the upper troposphere to the stratopause. Formaldehyde single profile retrieval is formally possible, however with a large noise error (more than 60%), which is the dominant error source. The number of degrees of freedom for single profile retrieval ranges from 2 to 4.5 depending on latitude and number of cloud-free tangent altitudes. Calculation of zonal mean values for 30 days of data during 8 September 2003 and 1 December 2003 reduces the noise induced error by a factor of 20 or more. In the upper tropical troposphere zonal mean values of about 70 parts per trillion by volume (pptv) were found, which have been attributed to biomass burning emissions. In the stratosphere, formaldehyde values are determined by photochemical reactions. In the upper tropical stratosphere, formaldehyde zonal mean maximum values can reach 130 pptv. Diurnal variations in this region can be up to 50 pptv. Comparisons with other satellite instruments show generally good agreement in the region of upper troposphere and lower stratosphere as well as in the upper stratosphere.

An in vitro model based on luteinised granulosa cells gained during an in vitro fertilisation programme examines the question of whether prednisolone, and thus glucocorticoids in general, are capable of exerting an influence on the secretion of oestradiol and progesterone. It can be demonstrated that prednisolone leads to dosage-dependent increases in the concentration of both steroids, even independently of concurrent stimulation by human chorionic gonadotropin. A similar mechanism for aromatase activity of human adipose cells is suggested.

International audience; Under cloud free conditions, the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) provides measurements of spectrally resolved limb radiances down to the upper troposphere. These are used to infer global distributions of mixing ratios of atmospheric constituents in the upper troposphere and the stratosphere. From 21 October to 12 November 2003, MIPAS observed enhanced amounts of upper tropospheric C2H6 (up to about 400 pptv) and ozone (up to about 80 ppbv). The absolute values of C2H6, however, may be systematically low by about 30% due to uncertainties of the spectroscopic data used. By means of trajectory calculations, the enhancements observed in the southern hemisphere are, at least partly, attributed to a biomass burning plume, which covers wide parts of the Southern hemisphere, from South America, the Atlantic Ocean, Africa, the Indian Ocean to Australia. The chemical composition of the part of the plume-like pollution belt associated with South American fires, where rainforest burning is predominant appears different from the part of the plume associated with southern African savanna burning. In particular, African savanna fires lead to a larger ozone enhancement than equatorial American fires. In this analysis, MIPAS observations of high ozone were disregarded where low CFC-11 (below 245 pptv) was observed, because this hints at a stratospheric component in the measured signal. Different type of vegetation burning (flaming versus smouldering combustion) has been identified as a candidate explanation for the different plume compositions.