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A Whole Country Cannot Be Comparatively Superior
No full textAn einem fehlerhaften Beispiel wird aufgezeigt, dass ein Land nicht in jedem Produkt einem anderen Land komparativ überlegen sein kann. Absolute Kostenvorteile sind in allen Produkten möglich, doch auch das unproduktivere Land besitzt in der Regel mindestens einen komparativen Kostenvorteil und sollte sich dann auf die Produktion des entsprechenden Gutes konzentrieren. Nur wenn das Einsatzverhältnis der Produktionsfaktoren für alle Güter und Länder gleich ist, hat keines einen komparativen Kostenvorteil und lohnt internationaler Handel nicht.On an erroneous example, it is shown that a country cannot be comparatively superior to another country in every product. Absolute cost advantages are possible for all products, but the less productive country usually also has at least one comparative cost advantage and should then concentrate on the production of the corresponding good. Only if the input ratio of the production factors is the same for all goods and countries, does no country have a comparative cost advantage and international trade is not worthwhile
Ethics Guidelines of the German Network for Forced Migration Studies
No full textThe Ethics Guidelines of the German Network for Forced Migration Studies (Netzwerk Fluchtforschung e.V.) aim to support ethical research practices in Forced Migration Studies. The Guidelines place the respect for human dignity and safeguarding the rights and well-being of all research participants, especially but not exclusively those with lived experience of displacement, at the heart of all research processes. The objective is to support ethical considerations, reflections and practices in Forced Migration Studies scholarship regardless of the chosen research methods. The Guidelines provide a practical framework for academics to make ethically informed decisions throughout the research process
Experimental and theoretical studies on self-diffusion in amorphous germanium
No full textSelf-diffusion in amorphous germanium is studied at temperatures between 325 and 370 °C utilizing amorphous isotopically controlled germanium multilayer structures. The isotope multilayer is epitaxially grown on a single crystalline germanium-on-insulator structure by means of molecular beam epitaxy and subsequently amorphized by self-ion implantation. After heat treatment, the diffusional broadening of the isotope structure is measured with time-of-flight secondary ion mass spectrometry. The temperature dependence of self-diffusion is accurately described by the Arrhenius equation with the activation enthalpy Q = (2.21 ± 0.12) eV and pre-exponential factor D_0=(2.32_{-2.10}^{+20.79}) cm^2 s^−1. The activation enthalpy equals the activation enthalpy of solid phase epitaxial recrystallization (SPER). This agreement suggests that self-diffusion in amorphous germanium is similar to SPER, also mainly mediated by local bond rearrangements. Classical molecular dynamics simulations with a modified Stillinger–Weber-type interatomic potential yield results that are consistent with the experimental data and support the proposed atomic mechanism
Extracellular vesicle-associated tyrosine kinase-like orphan receptors ROR1 and ROR2 promote breast cancer progression
No full textBackground: Extracellular vesicles (EVs) harbor a plethora of different biomolecules, which they can transport across cells. In cancer, tumor-derived EVs thereby support the creation of a favorable tumor microenvironment. So far, EV uptake and cargo delivery into target cells have been regarded as the main mechanisms for the pro-tumoral function of EVs. To test this hypothesis, we investigated the fate of the oncogenic transmembrane Wnt tyrosine kinase-like orphan receptor 1 and 2 (ROR1, ROR2) delivered via distinct EV subpopulations to breast cancer cells and aimed to unravel their impact on tumor progression. Methods: EVs were isolated by differential ultracentrifugation from cell culture supernatant as well as plasma samples from healthy individuals (n = 27) and breast cancer patients (n = 41). EVs were thoroughly characterized by electron microscopy, nanoparticle tracking analysis, immunoblot, and flow cytometry. ROR transfer to target cells was observed using microscopy-based assays and biodistribution experiments were conducted in syngeneic mice. EV impact on cancer cell migration and invasion was tested in functional assays. Results: We observed that the supernatant of ROR-overexpressing cells was sufficient for transferring the receptors to ROR-negative cells. Analyzing the secretome of the ROR-overexpressing cells, we detected a high enrichment of ROR1/2 on large and small EVs, but not on large oncosomes. Interestingly, the majority of ROR-positive EVs remained attached to the target cell surface after 24 h of stimulation and was quickly removed by treatment with trypsin. Nonetheless, ROR-positive EVs increased migration and invasion of breast cancer cells, even after chemically inhibiting EV uptake, in dependence of RhoA downstream signaling. In vivo, ROR-depleted EVs tended to distribute less into organs prone for the formation of breast cancer metastases. ROR-positive EVs were also significantly elevated in the plasma of breast cancer patients and allowed to separate them from healthy controls. Conclusions: The oncogenic Wnt receptors ROR1/2 are transferred via EVs to the surface of ROR-negative cancer cells, in which they induce an aggressive phenotype supporting tumor progression
Die binationale Eheschließung als Aushandlung: Regeln und Ausnahmen in Zeiten zunehmender Vielfalt (1870 –1930)
No full textDer Artikel versteht sich als Beitrag zur Geschichte der Eheschließung mit Nichtdeutschen. Im Untersuchungszeitraum zwischen dem letzten Drittel des 19. Jahrhunderts und den 1920er Jahren geht er der Frage nach, wie die damit betrauten Behörden – allen voran die in den 1870er Jahren ins Leben gerufenen Standesämter – auf die zunehmende nationale Vielfalt auf dem Heiratsmarkt reagiert haben. Diese wachsende Diversität in Bezug auf die Herkünfte von Ehebewerberinnen und Ehebewerbern führte zu dem Bestreben, eine möglichst große privatrechtliche Vereinheitlichung im Umgang mit den Eheanträgen herbeizuführen – nicht zuletzt, um rechtliche Unsicherheiten zu minimieren. In der Verwirklichung dieser rechtlichen "Einheit" kam es aus unterschiedlichen Gründen immer wieder zu normativen Konflikten, die in der rechtlichen Praxis zu Ausnahmeregelungen führten und Handlungsspielräume generierten – sowohl auf Seiten der Standesbeamten als auch für die Verlobten selbst.The article is a contribution to the history of marriages with non-Germans. Covering the period between the last third of the 19th century and the 1920s, it examines the question of how the authorities entrusted with this task – above all the registry offices established in the 1870s – reacted to the increasing national diversity on the marriage market. This growing diversity with regard to the origins of marriage applicants led to efforts to bring about the greatest possible standardisation under private law in the handling of marriage applications – not least in order to minimise legal uncertainties. In the realisation of this legal "unity", normative conflicts arose time and again for various reasons, which led to several exceptions in legal practice and generated room for manoeuvre – both on the part of the registrars and for the engaged couples themselves
A Data Model Inference Algorithm for Schemaless Process Modeling
No full textMobile devices have become ubiquitous not only in the consumer domain but also support the
digitalization of business operations though business apps. Many frameworks for programming
cross-platform apps have been proposed, but only few modeling approaches exist that focus on
platform-agnostic representations of mobile apps. In addition, app development activities are
almost exclusively performed by software developers, while domain experts are rarely involved in
the actual app creation beyond requirements engineering phases.
This work concentrates on a model-driven approach to app development that is also comprehensible
to non-technical users. With the help of a graphical domain-specific language, data model, view
representation, business logic, and user interactions are modeled in a common model from a
process perspective. To enable such an approach from a technical point of view, an inference
mechanism is presented that merges multiple partial data models into a global specification.
Through model transformations, native business apps can then be generated for multiple platforms
without manual programming
A Leray-Serre spectral sequence for Euclidean buildings
No full textDie Leray-Serre Spektralfolge ist ein algebraisches Werkzeug,
das auf Hurewicz-Faserungen angewandt wird. Unter guten Umständen
ermöglicht dieses Werkzeug, eine neue Homologie auf dem Basisraum
zu definieren, eine Homologie mit lokalen Koeffizienten, die außerdem
Informationen über die singuläre Homologie des Totalraumes liefert.
Ein euklidisches Gebäude ist ein besonderer Simplizialkomplex, auf dem
man eine Metrik definieren kann, die aus diesem einen CAT(0)-Raum macht.
Da ein euklidisches Gebäude kontrahierbar ist, ist seine singuläre Homologie
trivial. Also kann man sich eine neue Homologie für euklidische Gebäude wünschen.
In dieser Thesis konstruieren wir eine „Pseudo-Faserung“, in der ein euklidisches
Gebäude die Rolle des Basisraumes spielt, und dazu ein Analogon der Leray-Serre Spektralfolge, das wir auf diese Pseudo-Faserung anwenden.
In einem Schritt dieser Arbeit definieren wir darüber hinaus für bestimmte CAT(0)-Räume
(unter denen euklidische Gebäude sind) ein Analogon des Tangentialbündels riemannscher
Mannigfaltigkeiten, das „Richtungsbündel“ („direction bundle“).The Leray-Serre spectral sequence is an algebraic tool that applies
to Hurewicz fibrations. Under good circumstances, this tool enables
one to define a new homology on the base space of the fibration,
a homology with local coefficients, which will also deliver information
about the singular homology of the total space of the fibration.
Euclidean buildings are particular simplicial complexes that can be
equipped with a metric which makes them into CAT(0) spaces. They often
arise from certain groups that act on them, and they therefore help to
study these groups. Unfortunately, since Euclidean buildings are contractible,
their singular homology is trivial. Therefore, one may wish to obtain a new
homology for these. In this thesis, we construct a 'pseudo-fibration'
in which a Euclidean building fits as the base space, as well as an analogue of
the Leray-Serre spectral sequence that applies to this pseudo-fibration.
At some step of this work, we also define, for certain CAT(0) spaces and
in particular for Euclidean buildings, an analogue of the tangent bundle
of Riemannian manifolds, called the 'direction bundle'
Anforderungen an barrierefreie Online-Befragungen:Handreichung für Forschung und Lehre
No full textDer Muster-Foliensatz "Anforderungen an barrierefreie Online-Befragungen" bietet eine umfassende Übersicht zu den Anforderungen an die barrierefreie Gestaltung von Online-Befragungen für Forschung und Lehre. Ausgehend von der Relevanz von Barrierefreiheit angesichts der hohen Zahl von Menschen mit Behinderungen und eingeschränkten Kompetenzen wird die Notwendigkeit einer barrierefreien Umsetzung von empirischen Forschungsansätzen anhand der ethischen Prinzipien wie Gerechtigkeit und Schadensvermeidung deutlich. Methodische Herausforderungen werden durch Maßnahmen zur Reduktion von Abbrüchen und Verbesserung der Datenqualität adressiert. Rechtliche und technische Anforderungen, wie die UN-Behindertenrechtskonvention und die Web Content Accessibility Richtlinien 2.1 sind zentrale Bestandteile praktischer Empfehlungen zur visuellen Gestaltung, zur Integration von assistiven Technologien und zur benutzerfreundlichen Formulierung in Online-Befragungen in Einfacher Sprache. Der Muster-Foliensatz gibt damit Anregungen und praktische Hinweise, wie die Zugänglichkeit und Bedienbarkeit von Online-Befragungen für alle Nutzer:innen ermöglicht werden kann.The sample slides "Requirements for accessible online surveys" provide a comprehensive overview of the requirements for the accessible design of online surveys for research and teaching. Based on the relevance of accessibility in the light of the high number of people with disabilities and with restricted skills, the necessity of an accessible implementation of empirical research approaches is made clear on the basis of ethical principles such as justice and avoidance of harm. Methodological challenges are addressed by measures to reduce drop-outs and improve data quality. Legal and technical requirements, such as the UN Convention on the Rights of Persons with Disabilities and the Web Content Accessibility Guidelines 2.1, are central components of practical recommendations for visual design, the integration of assistive technologies and user-friendly wording in online surveys in plain language. The sample slide set thus provides suggestions and practical tips on how the accessibility and usability of online surveys can be made possible for all users
Challenges of Data Management and Analytics in Omni-Channel CRM
No full textData Management and Data Analytics are of huge importance to Business Process Outsourcing Providers in Customer Relationship Management (CRM) in order to offer tailor-made CRM Solutions to their business clients during presales, sales and aftersales. These solutions support business clients to improve their internal processes, as well as their customer service in a variety of communication channels (including e-mail, chat, social media, private messages, etc.) to reach out to end customers in an efficient way. As customer interactions may happen via various channels basically at any time, a crucial challenge is to efficiently store and integrate the data of the various channels in order to obtain a unified customer profile. This paper abstracts from the underlying platforms and instead considers the requirements to CRM solutions for the various communication channels, in order to devise a uniform and corporate-wide data architecture for an omni-channel customer view to maximize the business clients' value in customer retention and customer centric analytics. Especially, online customer segmentation integrating channel usage and preferences is presented as a very promising means for constructing a self-energising information loop which will lead to highly improved customer service along the whole customer journey
Combined Application of a Novel Robotic System and Exoscope for Microsurgical Anastomoses: Preclinical Performance
No full textBackground The concept of robotic microsurgery is becoming increasingly known as
several robotic systems tailored to the specific needs of microsurgery are being introduced.
Training with these devices is essential to draw conclusions about their potential clinical
utility. This study describes the training and learning curve of experienced microsurgeons
and complete novices using such a robotic surgical system in combination with an exoscope.
Methods Four experienced microsurgeons and three complete novices performed a
total of 62 manual and robot-assisted anastomoses. The time for anastomosis
completion and surgeon's satisfaction with the anastomosis and with the robotic
system were recorded. The anastomoses' quality was assessed using the Structured
Assessment of Microsurgery Skills (SAMS) and the Anastomosis Lapse Index (ALI). The
Rapid Entire Body Assessment (REBA) was used for ergonomics evaluation.
Results All expert microsurgeons and novices improved their performance during
training. The average anastomosis time decreased significantly, while satisfaction with
the anastomosis and robotic system increased significantly over time. Multiple SAMS
score parameters increased significantly throughout robotic but not manual training
and the ALI score demonstrated more errors in the manual group. The REBA score
displayed a significantly lower risk for musculoskeletal disorders in the robotic group.
Conclusion Currently, the first clinical applications of robotic surgical systems
specifically designed for microsurgery are being reported. The introduction of such
systems into clinical practice can be expected to have a steep learning curve, as
demonstrated in our study. Meanwhile, robotic systems for microsurgical procedures
may hold great potential for improvement of surgical quality and ergonomics