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Effects of variable ice–ocean surface properties and air mass transformation on the Arctic radiative energy budget
No full textLow-level airborne observations of the Arctic surface radiative energy budget are discussed. We fo-
cus on the terrestrial part of the budget, quantified by the thermal-infrared net irradiance (TNI). The data were
collected in cloudy and cloud-free conditions over and in the vicinity of the marginal sea ice zone (MIZ) close
to Svalbard during two aircraft campaigns conducted in the spring of 2019 and in the early summer of 2017. The
measurements, complemented by ground-based observations available from the literature and radiative transfer
simulations, are used to evaluate the influence of surface type (sea ice, open ocean, MIZ), seasonal characteris-
tics, and synoptically driven meridional air mass transports into and out of the Arctic on the near-surface TNI.
The analysis reveals a typical four-mode structure of the frequency distribution of the TNI as a function of sur-
face albedo, the sea ice fraction, and surface brightness temperature. Two modes prevail over sea ice and another
two over open ocean, each representing cloud-free and cloudy radiative states. Characteristic shifts and modifi-
cations of the TNI modes during the transition from winter to spring and early summer conditions are discussed.
Furthermore, the influence of warm air intrusions (WAIs) and marine cold-air outbreaks (MCAOs) on the near-
surface downward thermal-infrared irradiances and the TNI is highlighted for several case studies. It is concluded
that during WAIs the surface warming depends on cloud properties and evolution. Lifted clouds embedded in
warmer air masses over a colder sea ice surface, decoupled from the ground by a surface-based temperature
inversion, have the potential to warm the surface more strongly than near-surface fog or thin low-level boundary
layer clouds because of a higher cloud base temperature. For MCAOs it is found that the thermodynamic profile
of the southward-moving air mass adapts only slowly to the warmer ocean surface
Absolute scattering length density profile of liposome bilayers obtained by SAXS combined with GIXOS: a tool to determine model biomembrane structure
No full textLipid membranes play an essential role in biology, acting as host matrices for biomolecules like proteins and facilitating their functions. Their structures and structural responses to physiologically relevant interactions (i.e. with membrane proteins) provide key information for understanding biophysical mechanisms. Hence, there is a crucial need of methods to understand the effects of membrane host molecules on the lipid bilayer structure. Here, a purely experimental method is presented for obtaining the absolute scattering length density profile and the area per lipid of liposomal bilayers, by aiding the analysis of small-angle X-ray scattering (SAXS) data with the volume of bare headgroups obtained from grazing-incidence X-ray off-specular scattering (GIXOS) data of monolayers of the same model membrane lipid composition. The GIXOS data experimentally demonstrate that the variation of the bare headgroup volume upon change in lipid packing density is small enough to allow its usage as a reference value without knowing the lipid packing stage in a bilayer. This approach also has the advantage that the reference volume is obtained in the same aqueous environment as used for the model membrane bilayers. The validity of this method is demonstrated using several typical membrane compositions, as well as one example of a phospholipid membrane with an incorporated transmembrane peptide. This methodology allows us to obtain absolute scale rather than relative scale values using solely X-ray-based instrumentation, retaining a similar resolution to SAXS experiments. The method presented has high potential for understanding the structural effects of membrane proteins on the biomembrane structure
Fabrication of 3D Printed, Core-and-Shell Implants as Controlled Release Systems for Local siRNA Delivery
No full textThe development and clinical translation of small interfering RNA (siRNA) therapies remains challenging owing to their poor pharmacokinetics. 3D printing technology presents a great opportunity to fabricate personalized implants for local and sustained delivery of siRNA. Hydrogels can mimic the mechanical properties of tissues, avoiding the problems associated with rigid implants. Herein, a thermoresponsive composite hydrogel suitable for extrusion 3D-printing is formulated to fabricate controlled-release implants loaded with siRNA-Lipofectamine RNAiMAX complexes. A hydrogel matrix mainly composed of uncharged agarose to protect siRNA from decomplexation is selected. Additionally, pluronic F127 and gelatin are added to improve the printability, degradation, and cell adhesion to the implants. To avoid exposing siRNA to thermal stress during the printing process, a core-and-shell design is set up for the implants in which a core of siRNA-complexes loaded-pluronic F127 is printed without heat and enclosed with a shell comprising the thermoresponsive composite hydrogel. The release profile of siRNA-complexes is envisioned to be controlled by varying the printing patterns. The results reveal that the implants sustain siRNA release for one month. The intactness of the released siRNA-complexes is proven until the eighth day. Furthermore, by changing the printing patterns, the release profiles can be tailored
How language shapes our minds: On the relationship between generics, stereotypes and social norms
No full textIn this article, we discuss the role of labels and generics
referring to social kinds in mindshaping practices, arguing
that they promote generalizations that foster essentialist
thinking and carry a normative force. We propose that
their cognitive function consists in both contributing to
the formation and reinforcement of schemata and scripts
for social interaction and in activating these schemata in
specific social situations. Moreover, we suggest that failure
to meet the expectations engendered by these schemata
and scripts leads to the activation of “reactive attitudes”
embedded in feedback loops of reactive exchange that are
constitutive of our mindshaping practices
Auf dem Weg zur Abstraktion: das Problem des abstrakten Ausdrucks im Werk von Čiurlionis und seinen Zeitgenossen
No full textReview: Reperfusion Injury: How Can We Reduce It by Pre-, Per-, and Postconditioning
No full textWhile early coronary reperfusion via primary percutaneous coronary intervention (pPCI)
is established as the most efficacious therapy for minimizing infarct size (IS) in acute ST-elevation
myocardial infarction (STEMI), the restoration of blood flow also introduces myocardial ischemia-
reperfusion injury (IRI), leading to cardiomyocyte death. Among diverse methods, ischemic condi-
tioning (IC), achieved through repetitive cycles of ischemia and reperfusion, has emerged as the most
promising method to mitigate IRI. IC can be performed by applying the protective stimulus directly
to the affected myocardium or indirectly to non-affected tissue, which is known as remote ischemic
conditioning (RIC). In clinical practice, RIC is often applied by serial inflations and deflations of a
blood pressure cuff on a limb. Despite encouraging preclinical studies, as well as clinical studies
demonstrating reductions in enzymatic IS and myocardial injury on imaging, the observed impact on
clinical outcome has been disappointing so far. Nevertheless, previous studies indicate a potential
benefit of IC in high-risk STEMI patients. Additional research is needed to evaluate the impact of
IC in such high-risk cohorts. The objective of this review is to summarize the pathophysiological
background and preclinical and clinical data of IRI reduction by IC
Von der Dunkelheit zum Licht. Ukrainisches Musiktheater während des russisch-ukrainischen Krieges
No full textMusiktheater als Kulturwaffe im Krieg: Am Beispiel der Aufführungen des Lemberger Nationaltheaters für Oper und Ballett Solomia Kruschelnytska
No full textSeventy-five years West German currency reform: Crisis as catalyst for the erosion of the market order
No full textThe paper analyzes the role of the 1948 currency and eco-
nomic reform in West Germany for growth and social cohe-
sion in Germany and Europe. It describes the theoretical
foundation by Walter Eucken and the implementation and
defense of the new economic order by Ludwig Erhard. The
paper stresses the positive impact of the market economy
on growth and welfare in Germany and Europe. Then, it is
shown that Eucken's constituting principles of the market
economy were gradually eroded after euro introduction in
course of crises, with the negative repercussions on growth
and equality being explained. The policy conclusion is that
only the reconstitution of price stability in the euro area can
prevent a further decline of welfare in Europe. The 1948
economic reforms provide an important blueprint for the
necessary reform process