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Gender Gaps in the Measurement of Public Opinion About Homosexuality in Cross-national Surveys: A Question-Wording Experiment
Measures of attitudes towards homosexuality in cross-national studies have received criticism for not being ‘gender-sensitive’. The current study used a split-ballot design allowing for separate analyses of the attitudes towards ‘gay men and lesbian women’, ‘gay men’, and ‘lesbian women’ in a pooled sample of 3,381 participants from Great Britain, Hungary, and Portugal. Analyses controlling for sociodemographics showed that differences in attitudes towards male and female targets were generally small and did not interact with the gender of the rater. In addition, results showed that men’s attitudes towards homosexuality were more strongly related to their gender ideology than women’s attitudes. Implications of these findings for cross-national studies measuring attitudes towards homosexuality are discussed
Stammzellen der Neuralleiste im Gastrointestinaltrakt: Ansatz zur kausalen Therapie des Morbus Hirschsprung?
Zusammenfassung: Stammzellen sind selbsterneuernde Zellelemente mit dem Potenzial, verschiedene Zelltypen hervorzubringen. Der menschliche Körper benötigt Stammzellen zum Aufbau der Organe während der Embryonalentwicklung. Nach Abschluss der Organentwicklung sind Stammzellen auch zur Gewebeerhaltung ("Homöostase") und zur Gewebeerneuerung notwendig. Angesichts der vielfältigen Funktionen von Stammzellen erstaunt es nicht, dass Stammzellfehlentwicklungen zu Krankheiten führen können, wie z.B. zu M.Hirschsprung, einer Krankheit des enterischen Nervensystems mit komplexer Ätiologie. Ob Stammzellen zur Regeneration von krankhaften Organen eingesetzt werden könnten, wie dem enterischen Nervensystem bei M.Hirschsprung, ist Gegenstand intensiver Forschun
Dynamic hysteresis in Finemet thin films
We performed a series of dynamic hysteresis measurements on three series of
Finemet films with composition FeCuNbSiB, using
both the longitudinal magneto-optical Kerr effect (MOKE) and the inductive
fluxometric method. The MOKE dynamic hysteresis loops show a more marked
variability with the frequency than the inductive ones, while both measurements
show a similar dependence on the square root of frequency. We analyze these
results in the frame of a simple domain wall depinning model, which accounts
for the general behavior of the data.Comment: 3 pages, 3 figure
Geochemical and spectral characterization of naturally altered rock surfaces
The possibility of using the visible-near infrared region for compositional analysis of remotely sensed rock surfaces is studied. This would allow mapping rock type both on the Earth's surface and on other planetary surfaces. Reflectance spectroscopy, economic geology, optical depth determination, and X-ray diffraction mineralogy are discussed
Investigation of scaling properties of hysteresis in Finemet thin films
We study the behavior of hysteresis loops in Finemet
FeCuNbSiB thin films by using a fluxometric setup
based on a couple of well compensated pickup coils. The presence of scaling
laws of the hysteresis area is investigated as a function of the amplitude and
frequency of the applied field, considering sample thickness from about 20 nm
to 5 m. We do not observe any scaling predicted by theoretical models,
while dynamic loops show a logarithmic dependence on the frequency.Comment: 2 pages, 2 figure
A Statistical Model for Simultaneous Template Estimation, Bias Correction, and Registration of 3D Brain Images
Template estimation plays a crucial role in computational anatomy since it
provides reference frames for performing statistical analysis of the underlying
anatomical population variability. While building models for template
estimation, variability in sites and image acquisition protocols need to be
accounted for. To account for such variability, we propose a generative
template estimation model that makes simultaneous inference of both bias fields
in individual images, deformations for image registration, and variance
hyperparameters. In contrast, existing maximum a posterori based methods need
to rely on either bias-invariant similarity measures or robust image
normalization. Results on synthetic and real brain MRI images demonstrate the
capability of the model to capture heterogeneity in intensities and provide a
reliable template estimation from registration
Discovering Novel Gas-phase Nitrogen-heterocycle Formation Pathways With An Ab Initio Nanoreactor
Nitrogen-containing heterocycles pose an intriguing astrochemical mystery. 45 different varieties have been detected on meteorites with non-terrestrial isotopic abundances, but none have been detected in space, despite numerous search attempts.
It is unclear if these species are more likely to form through low-temperature gas-phase chemistry, photoprocessing of icy grains, aqueous chemistry in a meteorite parent body, or a combination of processes.
Further exploration of this question requires a broader catalog of potential N-heterocycle precursors, particularly for low temperature gas-phase chemistry.
Here, results of \textit{ab initio} molecular dynamics simulations of gas-phase N-heterocycle forming reactions will be discussed. These simulations were performed with an \textit{ab initio} nanoreactor, a computational tool developed for chemical reaction discovery.
Multiple novel gas-phase N-heterocycle formation pathways have been revealed, and many reactants are similar to known interstellar molecules. These simulations also reinforce previous experimental and theoretical studies which demonstrated that smaller N-heterocycles are potential precursors to larger ones. While these simulations cannot provide direct insight into interstellar chemistry, they have revealed nonintuitive N-heterocycle precursors that warrant further experimental and astronomical study
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