Transport Costs in International Trade

This paper claims that distance alone is a poor proxy for international transport costs in gravity equations. We develop a theoretical framework with a manufacturing and a transport sector, where the level of manufacturing exports determines the demand for transport. Above a certain threshold, transport service suppliers find it profit-maximizing to invest into advanced transport technology, which lowers their marginal costs and as a consequence, transport prices. Transport costs therefore vary with the distance between the two locations, and with the endogenous decision to invest in a more efficient technology. We tackle the biases in traditional gravity estimates by using newly collected data on transport prices from UPS and by applying instrument variable estimation techniques. Our results reveal that distance affects trade beyond the transport cost channel. Transport prices, in turn, are influenced by the distance and by the exports between two countries. We find that trading partners with 10% more exports enjoy 0.7% lower transport prices.

Monopoles in the presence of the Chern-Simons term via the Julia-Toulouse approach

We study $QED_3$ with magnetic-like defects using the Julia-Toulouse condensation mechanism (JTM). By a careful treatment of the symmetries we suggest a geometrical interpretation for distinct debatable issues in the MCS-monopole system: (i) the induction of the non-conserved electric current together with the Chern-Simons term (CS), (ii) the deconfinement transition and, (iii) the computation of the fermionic determinant in the presence of Dirac string singularities. The JTM leads to proper interpretation of the non-conserved current as originating from Dirac brane symmetry breaking. The mechanism behind this symmetry breaking is clarified. The physical origin of the deconfinement transition becomes evident in the low energy effective theory induced by the JTM. The proper procedure to compute the fermionic determinant in the presence of Dirac branes will be presented. A byproduct of this approach is the possible appearance of statistical transmutation and the clarification for the different quantization rules for the topological mass.Comment: 6 pages, 2 figures, minor changes, references added, accepted for publication in Physics Letters

Duality and confinement in D=3 models driven by condensation of topological defects

We study the interplay of duality and confinement in certain three-dimensional models induced by the condensation of topological defects. To this end we check for the confinement phenomenon, in both sides of the duality, using the static quantum potential within the framework of the gauge-invariant but path-dependent variables formalism. Our calculations show that the interaction energy contains a linear term leading to the confinement of static probe charges.Comment: 13 pages, RevTex; correction for a mispelled author, final version to be published in Phys. Lett.

Was macht die "Frische" von Brot aus?

Die Frische von Brot lässt sich nicht mit einheitlichen Kriterien beurteilen. Vielmehr hängt die Wahl der jeweiligen Kritereien von den Anforderungen ab, die an das Produkt gestellt werden. Sensorische Eigenschaften spielen dabei eine bedeutende Rolle. An der Zürcher Hochschule für Angewandte Wissenschaften (ZHAW) in Wädenswil wurde im Rahmen einer studentischen Arbeit eine Studie zum Thema „Definition der Frische von Brot aus Konsumentensicht“ durchgeführt

U(1) effective confinement theory from SU(2) restricted gauge theory via the Julia-Toulouse Approach

We derive an U(1) effective theory of color confinement by applying the so-called Julia-Toulouse Approach for defects condensation to the SU(2) restricted gauge theory defined by means of the Cho decomposition of the non-abelian connection. Cho's geometric construction naturally displays the topological degrees of freedom of the theory and can be used to put the Yang-Mills action into an abelianized form under certain conditions. On the other hand, the use of the Julia-Toulouse prescription to deal with the monopole condensation leads to an effective action describing the phase whose dynamics is dominated by the magnetic condensate. The effective theory we found describes the interaction between external electric currents displaying a short-range Yukawa interaction plus a linear confinement term that governs the long distance physics.Comment: 7 page

Prevalence of Uncontrolled Hypertension in Patients With Fabry Disease

Background: Fabry disease is a rare X-linked disease arising from deficiency of α-galactosidase A. It results in early death related to renal, cardiac, and cerebrovascular disease, which are also important outcomes in patients with elevated blood pressure (BP). The prevalence of uncontrolled hypertension, as well as the effect of enzyme replacement therapy on BP, in patients with Fabry disease is unknown. Methods: We examined uncontrolled hypertension (systolic BP [SBP] ≥130 mm Hg or diastolic BP [DBP] ≥80 mm Hg) among 391 patients with Fabry disease who were participating in the Fabry Outcome Survey (FOS). Results: Uncontrolled hypertension was present in 57% of men and 47% of women. In patients with chronic kidney disease (CKD) stage 1 (n100), median SBP was 120 mm Hg and median DBP was 74 mm Hg. In patients with CKD stage 2 (n172), median SBP was 125 mm Hg and median DBP was 75 mm Hg. In patients with CKD stage 3 (n63), median SBP was 130 mm Hg and median DBP was 75 mm Hg. There was a significant decrease in both SBP and DBP during a 2-year course of enzyme replacement therapy. Conclusions: This study revealed a high prevalence of uncontrolled hypertension among patients with Fabry disease. Thus there is a need to improve BP control and renoprotection in patients with Fabry diseas

The HAAWAII Framework for Automatic Speech Understanding of Air Traffic Communication

During the last decade many successful applications combining Automatic Speech Recognition and Understanding (ASRU) for Air Traffic Management applications have been proposed and demonstrated. The HAAWAII project developed a generic architecture and framework, which was validated for, e.g., callsign highlighting, pre-filling radar labels and readback error detection. It supports recognizing and understanding pilot and air traffic controller (ATCo) transmissions. Contextual information extracted from available surveillance data, from flight plan data and from previous transmissions can be exploited to significantly improve ASRU performance. Different design decisions have been taken, depending on concrete scenarios. This paper evaluates the effect of the design decisions integrated in the HAAWAII framework on overall performance for speech understanding based on eight hypotheses, of which seven are validated. Using all framework elements enables command recognition rates for ATCos of 90% for real-time applications and 93% for offline applications, respectively. The most significant impact is achieved, when callsign information from surveillance data is available: the command recognition rate improves by more than 20% absolute. Knowing apriori, whether ATCo or pilot is speaking, can provide additional improvement in command recognition rate up to 16% absolute. The reported results are based on commands from apron, approach, and enroute recorded both in laboratory and in ops room environment

Midkine Controls Arteriogenesis by Regulating the Bioavailability of Vascular Endothelial Growth Factor A and the Expression of Nitric Oxide Synthase 1 and 3

Midkine is a pleiotropic factor, which is involved in angiogenesis. However, its mode of action in this process is still ill defined. The function of midkine in arteriogenesis, the growth of natural bypasses from pre-existing collateral arteries, compensating for the loss of an occluded artery has never been investigated. Arteriogenesis is an inflammatory process, which relies on the proliferation of endothelial cells and smooth muscle cells. We show that midkine deficiency strikingly interferes with the proliferation of endothelial cells in arteriogenesis, thereby interfering with the process of collateral artery growth. We identified midkine to be responsible for increased plasma levels of vascular endothelial growth factor A (VEGFA), necessary and sufficient to promote endothelial cell proliferation in growing collaterals. Mechanistically, we demonstrate that leukocyte domiciled midkine mediates increased plasma levels of VEGFA relevant for upregulation of endothelial nitric oxide synthase 1 and 3, necessary for proper endothelial cell proliferation, and that non-leukocyte domiciled midkine additionally improves vasodilation. The data provided on the role of midkine in endothelial proliferation are likely to be relevant for both, the process of arteriogenesis and angiogenesis. Moreover, our data might help to estimate the therapeutic effect of clinically applied VEGFA in patients with vascular occlusive diseases

Nos2 Inactivation Promotes the Development of Medulloblastoma in Ptch1+/− Mice by Deregulation of Gap43–Dependent Granule Cell Precursor Migration

Medulloblastoma is the most common malignant brain tumor in children. A subset of medulloblastoma originates from granule cell precursors (GCPs) of the developing cerebellum and demonstrates aberrant hedgehog signaling, typically due to inactivating mutations in the receptor PTCH1, a pathomechanism recapitulated in Ptch1+/− mice. As nitric oxide may regulate GCP proliferation and differentiation, we crossed Ptch1+/− mice with mice lacking inducible nitric oxide synthase (Nos2) to investigate a possible influence on tumorigenesis. We observed a two-fold higher medulloblastoma rate in Ptch1+/− Nos2−/− mice compared to Ptch1+/− Nos2+/+ mice. To identify the molecular mechanisms underlying this finding, we performed gene expression profiling of medulloblastomas from both genotypes, as well as normal cerebellar tissue samples of different developmental stages and genotypes. Downregulation of hedgehog target genes was observed in postnatal cerebellum from Ptch1+/+ Nos2−/− mice but not from Ptch1+/− Nos2−/− mice. The most consistent effect of Nos2 deficiency was downregulation of growth-associated protein 43 (Gap43). Functional studies in neuronal progenitor cells demonstrated nitric oxide dependence of Gap43 expression and impaired migration upon Gap43 knock-down. Both effects were confirmed in situ by immunofluorescence analyses on tissue sections of the developing cerebellum. Finally, the number of proliferating GCPs at the cerebellar periphery was decreased in Ptch1+/+ Nos2−/− mice but increased in Ptch1+/− Nos2−/− mice relative to Ptch1+/− Nos2+/+ mice. Taken together, these results indicate that Nos2 deficiency promotes medulloblastoma development in Ptch1+/− mice through retention of proliferating GCPs in the external granular layer due to reduced Gap43 expression. This study illustrates a new role of nitric oxide signaling in cerebellar development and demonstrates that the localization of pre-neoplastic cells during morphogenesis is crucial for their malignant progression