Predictive factors for ovarian response in a corifollitropin alfa/GnRH antagonist protocol for controlled ovarian stimulation in IVF/ICSI cycles

Background This secondary analysis aimed to identify predictors of low (<6 oocytes retrieved) and high ovarian response (>18 oocytes retrieved) in IVF patients undergoing controlled ovarian stimulation with corifollitropin alfa in a gonadotropin-releasing hormone (GnRH) antagonist protocol. Methods Statistical model building for high and low ovarian response was based on the 150 μg corifollitropin alfa treatment group of the Pursue trial in infertile women aged 35–42 years (n = 694). Results Multivariable logistic regression models were constructed in a stepwise fashion (P <0.05 for entry). 14.1 % of subjects were high ovarian responders and 23.2 % were low ovarian responders. The regression model for high ovarian response included four independent predictors: higher anti-Müllerian hormone (AMH) and antral follicle count (AFC) increased the risk, and higher follicle-stimulating hormone (FSH) levels and advancing age decreased the risk of high ovarian response. The regression model for low ovarian response also included four independent predictors: advancing age increased the risk, and higher AMH, higher AFC and longer menstrual cycle length decreased the risk of low ovarian response. Conclusions AMH, AFC and age predicted both high and low ovarian responses, FSH predicted high ovarian response, and menstrual cycle length predicted low ovarian response in a corifollitropin alfa/GnRH antagonist protocol

Toward a script theory of guidance in computer-supported collaborative learning

This article presents an outline of a script theory of guidance for computer-supported collaborative learning (CSCL). With its four types of components of internal and external scripts (play, scene, role, and scriptlet) and seven principles, this theory addresses the question how CSCL practices are shaped by dynamically re-configured internal collaboration scripts of the participating learners. Furthermore, it explains how internal collaboration scripts develop through participation in CSCL practices. It emphasizes the importance of active application of subject matter knowledge in CSCL practices, and it prioritizes transactive over non-transactive forms of knowledge application in order to facilitate learning. Further, the theory explains how external collaboration scripts modify CSCL practices and how they influence the development of internal collaboration scripts. The principles specify an optimal scaffolding level for external collaboration scripts and allow for the formulation of hypotheses about the fading of external collaboration scripts. Finally, the article points towards conceptual challenges and future research questions

Electrostatic colloid-membrane complexation

We investigate numerically and on the scaling level the adsorption of a charged colloid on an oppositely charged flexible membrane. We show that the long ranged character of the electrostatic interaction leads to a wrapping reentrance of the complex as the salt concentration is varied. The membrane wrapping depends on the size of the colloid and on the salt concentration and only for intermediate salt concentration and colloid sizes we find full wrapping. From the scaling model we derive simple relations for the phase boundaries between the different states of the complex, which agree well with the numerical minimization of the free energy.Comment: 7 page, 11 figure

Gravitationswellen von Kernkollaps-Supernovae

The very first direct detection of gravitational waves from a black hole merger opened up a new field of observation to astrophysics. In this context, previous studies also examined upcoming core-collapse supernovae in the Local Group of the Milky Way. Strong hints lead to the assumption that they are potential sources of gravitational waves which we could measure with present gravitational wave detectors on earth. In this work, we review the current knowledge of the theory of core-collapse supernovae. Furthermore, we deliver a summary of the physical description of gravitational waves. Finally, we develop a simple model of a collapsing stellar core which is deformed by rotation into an oblate spheroid. At a distance of r = 10 kpc, we could measure linear polarized gravitation waves in order of magnitude hx ~ 1-3 x 10-21 on the equatorial plane. We show that the results are in agreement with typical gravitational wave signals from previous core-collapse simulations

Potential Neutrino Signals from Galactic Gamma-Ray Sources

The recent progress made in Galactic gamma-ray astronomy using the High Energy Stereoskopic System (H.E.S.S.) instrument provides for the first time a population of Galactic TeV gamma-rays, and hence potential neutrino sources, for which the neutrino flux can be estimated. Using the energy spectra and source morphologies measured by H.E.S.S., together with new parameterisations of pion production and decay in hadronic interactions, we estimate the signal and background rates expected for these sources in a first-generation water Cherenkov detector (ANTARES) and a next-generation neutrino telescope in the Mediterranean Sea, KM3NeT, with an instrumented volume of 1 km^3. We find that the brightest gamma-ray sources produce neutrino rates above 1 TeV, comparable to the background from atmospheric neutrinos. The expected event rates of the brightest sources in the ANTARES detector make a detection unlikely. However, for a 1 km^3 KM3NeT detector, event rates of a few neutrinos per year from these sources are expected, and the detection of individual sources seems possible. Although generally these estimates should be taken as flux upper limits, we discuss the conditions and type of gamma-ray sources for which the neutrino flux predictions can be considered robust.Comment: 20 pages, 4 figures; v2: ERROR in energy scale of KM3NeT effective neutrino area corrected which resulted in event rates being about a factor 3 too low; v3: grammatical changes and update of references after receiving proof

Influence of infertility diagnosis on pregnancy outcome in ART

Abstract Objective: To determine the influence of the infertility diagnosis on gestational age (GA) and birth weight (BW) of children conceived using assisted reproductive technology (ART). Design: Retrospective cohort. Setting: University-affiliated infertility clinic. Patients: Women with a singleton live birth following their first fresh ART cycle with autologous oocytes. Interventions: Patients were stratified into groups based on infertility diagnosis. GA and BW of their infants were compared. Main Outcome Measures: GA and BW of children conceived using ART. Results: 397 women were included. Average GA in the cohort was 38.7±2.3 weeks and average BW was 3301.5±633.8 grams. Maternal age, BMI, and parity were significantly different between groups. After controlling for these factors and stratifying by infertility diagnosis, there was no difference in GA or BW in infants conceived with ART. Conclusions: Contrary to previously reported data, there was no difference in GA or BW in infants conceived with ART when stratified by infertility diagnosis. Our results were not different from the national population; however GA was one week longer in our cohort than in the national ART database. These data suggest a difference exists between our cohort and the ART population at large. We propose that the main difference is our institution’s focus on single embryo transfer

IL-18-induced expression of high-affinity IL-2R on murine NK cells is essential for NK-cell IFN-γ production during murine Plasmodium yoelii infection.

Early production of pro-inflammatory cytokines, including IFN-γ, is essential for control of blood-stage malaria infections. We have shown that IFN-γ production can be induced among human natural killer (NK) cells by coculture with Plasmodium falciparum infected erythrocytes, but the importance of this response is unclear. To further explore the role of NK cells during malaria infection, we have characterized the NK-cell response of C57BL/6 mice during lethal (PyYM) or nonlethal (Py17XNL) P. yoelii infection. Ex vivo flow cytometry revealed that NK cells are activated within 24 h of Py17XNL blood-stage infection, expressing CD25 and producing IFN-γ; this response was blunted and delayed during PyYM infection. CD25 expression and IFN-γ production were highly correlated, suggesting a causal relationship between the two responses. Subsequent in vitro experiments revealed that IL-18 signaling is essential for induction of CD25 and synergizes with IL-12 to enhance CD25 expression on splenic NK cells. In accordance with this, Py17XNL-infected erythrocytes induced NK-cell CD25 expression and IFN-γ production in a manner that is completely IL-18- and partially IL-12-dependent, and IFN-γ production is enhanced by IL-2. These data suggest that IL-2 signaling via CD25 amplifies IL-18- and IL-12-mediated NK-cell activation during malaria infection