When half the truth is better than the truth: A Theory of aggregate information cascades

We introduce a new model of aggregate information cascades where only one of two possible actions is observable to others. When called upon, agents (who decide in some random order that they do not know) are only informed about the total number of others who have chosen the observable action before them. This informational structure arises nat- urally in many applications. Our most important result is that only one type of cascade arises in equilibrium, the aggregate cascade on the observable action. A cascade on the unobservable action never arises. Our results may have important policy consequences. Central agencies, for example in the health sector, may optimally decide to withhold in- formation from the public.

Hippocampal neurogenesis requires cell-autonomous thyroid hormone signaling

Adult hippocampal neurogenesis is strongly dependent on thyroid hormone (TH). Whether TH signaling regulates this process in a cell-autonomous or non-autonomous manner remains unknown. To answer this question, we used global and conditional knockouts of the TH transporter monocarboxylate transporter 8 (MCT8), having first used FACS and immunohistochemistry to demonstrate that MCT8 is the only TH transporter expressed on neuroblasts and adult slice cultures to confirm a necessary role for MCT8 in neurogenesis. Both mice with a global deletion or an adult neural stem cell-specific deletion of MCT8 showed decreased expression of the cell-cycle inhibitor P27KIP1, reduced differentiation of neuroblasts, and impaired generation of new granule cell neurons, with global knockout mice also showing enhanced neuroblast proliferation. Together, our results reveal a cell-autonomous role for TH signaling in adult hippocampal neurogenesis alongside non-cell-autonomous effects on cell proliferation earlier in the lineage

Discrimination, narratives and family history: an experiment with Jordanian host and Syrian refugee children

We measure the prevalence of discrimination between Jordanian host and Syrian refugee children attending school in Jordan. Using a simple sharing experiment, we find only little discrimination. Among the Jordanian children, however, we see that those who descended from Palestinian refugees do not discriminate at all, suggesting that a family history of refugee status can generate solidarity with new refugees. We also find that parents' narratives about the refugee crisis are correlated with the degree of discrimination, suggesting that discriminatory preferences are being transmitted through parental attitudes

Visumpolitik und die Regulierung globaler Mobilität. Ein Vergleich dreier OECD Länder

This article deals with the historical development of visa waiver policies in three selected OECD countries, the USA, Austria, and Finland, since 1960. Its point of departure is the question whether, in the context of globalization, mobility has become easier, or whether, in contrast, borders have become more selective. This issue is taken up by looking at short term mobility and the development of policies with the aim of waiving visa requirements. Our findings indicate that political and economic factors have become increasingly important when it comes to choosing who is allowed and who is denied access without a visa. Citizens from “rich democracies” are granted enhanced mobility rights while citizens from the “Global South” have to undergo lengthy visa application processes. The article also documents the fact that visa waiver policies are increasingly converging in the OECD world and that we find an asymmetry of visa waiver policies in relations to non-OECD countries. Globalization, evidently, is not just a matter of mobility. Rather, it produces mobility and immobility at the same time. This is established though rules of selective access and control as manifested in visa waiver policies.Der Artikel untersucht die historische Entwicklung von Visumbefreiungspolitiken in drei ausgewählten OECD-Ländern, den USA, Österreich und Finnland, für den Zeitraum seit dem Ende des zweiten Weltkrieges. Ausgangspunkt ist die Frage, ob im Zuge von Globalisierungsprozessen Mobilitätserleichterungen zugenommen haben oder ob im Gegenteil Grenzen nicht viel selektiver wurden. Dieser Frage gehen wir am Beispiel kurzfristiger Personenmobilität und sich verändernder Visumbefreiungspolitiken nach. Dabei wird deutlich, dass die Untersuchungsländer immer strengere Auswahlkriterien für die Befreiung von der Visumpflicht anwenden, sich also die Selektivität mit der Zeit erhöht. Zudem wird gezeigt, dass politische und ökonomische Faktoren ausschlaggebend dafür sind, welche Länder von einer Visumbefreiung profitieren und dass erweiterte Mobilitätsrechte vor allem an Bürger reicher Demokratien vergeben werden. Zugleich dokumentiert der Artikel zum einen die zunehmende Übereinstimmung der Regelungen zur Visumbefreiung innerhalb der OECD-Welt (Konvergenz) und zum anderen die Asymmetrie der Visumbefreiungen im Verhältnis von OECD-Ländern zu Nicht-OECD-Ländern. Globalisierung ist daher weder als Öffnung noch als Schließung zu interpretieren, sondern als Gleichzeitigkeit von Mobilität und Immobilität, welche vor allem über Regeln des selektiven Zugangs durchgesetzt wird

ELISA- and Activity Assay-Based Quantification of BMP-2 Released In Vitro Can Be Biased by Solubility in “Physiological” Buffers and an Interfering Effect of Chitosan

Chitosan nanogel-coated polycaprolactone (PCL) fiber mat-based implant prototypes with tailored release of bone morphogenic protein 2 (BMP-2) are a promising approach to achieve implant-mediated bone regeneration. In order to ensure reliable in vitro release results, the robustness of a commercially available ELISA for E. coli-derived BMP-2 and the parallel determination of BMP-2 recovery using a quantitative biological activity assay were investigated within a common release setup, with special reference to solubility and matrix effects. Without bovine serum albumin and Tween 20 as solubilizing additives to release media buffed at physiological pH, BMP-2 recoveries after release were notably reduced. In contrast, the addition of chitosan to release samples caused an excessive recovery. A possible explanation for these effects is the reversible aggregation tendency of BMP-2, which might be influenced by an interaction with chitosan. The interfering effects highlighted in this study are of great importance for bio-assay-based BMP-2 quantification, especially in the context of pharmaceutical release experiments

MULTISENSORY DLA BIOSENSORÓW PEŁNOKOMÓRKOWYCH

Whole-cell biosensors, which can be used in the environmental protection and process measuring technology, in the biotechnology, food and pharmaceutical industry for the on-line control and monitoring of chemical and biochemical processes and for the fast detection of small amounts of solutes, are of great interest. These kind of  biosensors comprise microorganisms like genetically modified yeast cells, which react on a specific stimulus, e.g. a residual amount of drugs in the measurement medium with a dependent fluorescence. The receptors of the cells detect specific signal molecules and stimulate the organism to produce a fluorescent protein. In this work, a combined impedimetric-optical read out was used, which can provide the reliable and long-term stable detection of a fluorescence signal accompanied by impedance measurements monitoring cell vitality and activity. A new challenge thereby is a special sensor design which enables the integration of excitation source,  photodetector, interdigitated electrodes, and the fluidic system with an effective and long-term-stable packaging.Biosensory pełnokomórkowe cieszą się bardzo dużym zainteresowaniem. Mogą one być wykorzystywane w ochronie środowiska i technologii pomiaru procesów, w branży biotechnologicznej, spożywczej i farmaceutycznej do kontrolowania i monitorowania procesów chemicznych i biochemicznych on-line oraz do szybkiego wykrywania niewielkich ilości substancji rozpuszczonych,. Tego rodzaju biosensory obejmują mikroorganizmy, takie jak genetycznie zmodyfikowane komórki drożdży, które reagują na specyficzny bodziec, np. fluorescencją na resztkowa ilość leków w pożywce pomiarowej. Receptory komórek wykrywają określone cząsteczki sygnałowe i stymulują organizm do wytwarzania białka fluorescencyjnego. W pracy wykorzystano łączony odczyt impedancyjno-optyczny, który może zapewnić niezawodną i długotrwale stabilną detekcję sygnału fluorescencyjnego, któremu towarzyszą pomiary impedancji monitorujące żywotność i aktywność komórek. Nowym wyzwaniem jest specjalna konstrukcja czujnika, która umożliwia integrację źródła pobudzenia, fotodetektora, elektrod palcowych i układu płynowego w jednej obudowie

Product lifecycle and choice of transportation modes: Japan’s evidence of import and export

Here we test the hypothesis that commodities at their peak valuation are transported by air and those at their birth and maturity are shipped by sea, and that shippers would choose air for transporting high-valued commodities. We empirically investigated how the product lifecycle of commodities is reflected by shippers' choices of air transportation rather than seaborne transportation. We also assumed that the commodities that achieved substantial innovation in their lifecycles would be moved by air transportation so that these commodities could reach the targeted markets as quickly as possible to avoid the opportunity costs that might be generated by missed business chances. We constructed two unbalanced panel data of 18 commodities (the case of import) and 14 commodities (the case of export) for 24 years from Japan’s custom, demographic, and international statistics. By estimating structural equation systems that consisted of commodity-specific import/export and import/export air ratio functions, we found that the product lifecycle of cargo outgoing from Japan exactly matched the upward and downward move of the air ratio, whereas since incoming commodities are raw materials that have little to do with product lifecycle or matured phase in their lifecycle stage, the peak of commodities’ valuations and the use of air transportation were not necessarily synchronized

Fundraising on the Internet

Abstract We take a first step towards analysing fundraising on the internet. Internet fundraising allows for the possibility of instantaneous feedback on campaign progress. Analysing data from a large number of small scale internet fundraising campaigns we show that the rich feed-back information provided to donors alters subsequent donor behaviour. In particular, early donors set a precedent for later donors

Mobiles, ortsbezogenes Lernen in der Ernährungs- und Verbraucherbildung

Im MILE-Projekt werden digitale Technologien für mobile, ortsbezogene Lernangebote in der Ernährungs- und Verbraucherbildung (EVB) genutzt. Ziel ist es, mit sog. MILEGeogames Jugendliche für Themen der EVB zu sensibilisieren. Die im Projekt entwickelte MILE.Toolbox unterstützt Multiplikatoren bei der Erstellung von MILE-Geogames. Der Beitrag diskutiert das Potential des Ansatzes für die Ernährungs- und Verbraucherbildung. (DIPF/Orig.