The excess volatility of foreign exchange rates: Statistical puzzle or theoretical artifact?

The inability to reconcile observed levels of foreign exchange rate volatility with predictions derived from rational expectations models represents one of the most persistent challenges in international nance. This paper shows that such excess volatility puzzles arise from informational assumptions by contrasting exchange rate equilibria under two different hypotheses: rational expectations and their generalization, rational beliefs. Under the latter agents hold data rather than model consistent expectations requiring learning and inference. Uncertainty arises endogenously as agents with diverse beliefs might trade even in the absence of new information. An analysis of currency volatility mechanisms now reveals that excess volatility is a theoretical consequence of rational expectations' structural knowledge assumptions. Markets only transmit volatility from exogenous variables to exchange rates without any amplication mechanism. Hence, rational expectations equilibria provide a lower volatility bound on more general exchange rate processes solving the excess volatility puzzle in terms of endogenous volatility generation. Finally, the results are applied to explore the structure of currency crises as short-lived rational deviations from economic fundamentals. --

Hydrothermisch behandelte Lupinen zur Eiweißversorgung der Milchkuh

According to producer statements hydrothermal treatment of lupines increases the amount of rumen undegradable protein (UDP) from 20 % to 45 % and nXP values from 196 to 245 g/kg thus providing sufficient protein for dairy cows. To evaluate the effects of hydrothermal treatment on nutritive value of lupines, intestinal protein supply and lactation performance as well as economical and ecological efficiency, a nine months feeding trial was carried out at the Agricultural Centre Haus Riswick, Kleve. Two groups of 20 cows blocked by milk yield, parity and expected calving date were fed a forage diet of grass-clover and corn silage enriched with 3 kg of concentrates (46 % blue lupine, 41 % triticale, 10 % wheat bran, 2 % mineral feed, 1 % rape oil), sufficient for 25 kg ECM (DLG, 2001). Nutrient values per kg dry matter were as follows (control/experiment): 6,8 / 6,8 MJ NEL, 168 / 168 g XP, 144 / 148 g nXP, 3,9 / 3,2 g RNB. Nutritive value of lupines was determined by feeding wethers according to standard procedure (GfE, 1991). Protein fractions were analysed according to Shannak et al. (2000). Experimental groups varied only in lupine treatment (Börde Kraftkorn, Gröningen, GER). Yield of natural and energy corrected milk (ECM), milk fat and milk protein were higher in cows fed treated lupines (p <0,001). Urea nitrogen concentration was marginally lower compared to controls (p <0,001). Improvement of lactational performance was slightly higher during the first 100 days of lactation, but persisted during the whole lactational period. Body weight and condition were not affected by treatment. Improved lactational performance resulted in an overall better economic result

Tuning the corona-core ratio of polyplex micelles for selective oligonucleotide delivery to hepatocytes or hepatic immune cells

Targeted delivery of oligonucleotides or small molecular drugs to hepatocytes, the liver's parenchymal cells, is challenging without targeting moiety due to the highly efficient mononuclear phagocyte system (MPS) of the liver. The MPS comprises Kupffer cells and specialized sinusoidal endothelial cells, efficiently clearing nanocarriers regardless of their size and surface properties. Physiologically, this non-parenchymal shield protects hepatocytes; however, these local barriers must be overcome for drug delivery. Nanocarrier structural properties strongly influence tissue penetration, in vivo pharmacokinetics, and biodistribution profile. Here we demonstrate the in vivo biodistribution of polyplex micelles formed by polyion complexation of short interfering (si)RNA with modified poly(ethylene glycol)-block-poly(allyl glycidyl ether) (PEG-b-PAGE) diblock copolymer that carries amino moieties in the side chain. The ratio between PEG corona and siRNA complexed PAGE core of polyplex micelles was chemically varied by altering the degree of polymerization of PAGE. Applying Raman-spectroscopy and dynamic in silico modeling on the polyplex micelles, we determined the corona-core ratio (CCR) and visualized the possible micellar structure with varying CCR. The results for this model system reveal that polyplex micelles with higher CCR, i.e., better PEG coverage, exclusively accumulate and thus allow passive cell-type-specific targeting towards hepatocytes, overcoming the macrophage-rich reticuloendothelial barrier of the liver

Targeted delivery of a phosphoinositide 3-kinase γ inhibitor to restore organ function in sepsis

Jaundice, the clinical hallmark of infection-associated liver dysfunction, reflects altered membrane organization of the canalicular pole of hepatocytes and portends poor outcomes. Mice lacking phosphoinositide 3-kinase-γ (PI3Kγ) are protected against membrane disintegration and hepatic excretory dysfunction. However, they exhibit a severe immune defect that hinders neutrophil recruitment to sites of infection. To exploit the therapeutic potential of PI3Kγ inhibition in sepsis, a targeted approach to deliver drugs to hepatic parenchymal cells without compromising other cells, in particular immune cells, seems warranted. Here, we demonstrate that nanocarriers functionalized through DY-635, a fluorescent polymethine dye, and a ligand of organic anion transporters can selectively deliver therapeutics to hepatic parenchymal cells. Applying this strategy to a murine model of sepsis, we observed the PI3Kγ-dependent restoration of biliary canalicular architecture, maintained excretory liver function, and improved survival without impairing host defense mechanisms. This strategy carries the potential to expand targeted nanomedicines to disease entities with systemic inflammation and concomitantly impaired barrier functionality

Influence of socioeconomic factors on medically unnecessary ambulance calls

<p>Abstract</p> <p>Background</p> <p>Unnecessary ambulance use has become a socioeconomic problem in Japan. We investigated the possible relations between socioeconomic factors and medically unnecessary ambulance calls, and we estimated the incremental demand for unnecessary ambulance use produced by socioeconomic factors.</p> <p>Methods</p> <p>We conducted a self-administered questionnaire-based survey targeting residents of Yokohama, Japan. The questionnaire included questions pertaining to socioeconomic characteristics, dichotomous choice method questions pertaining to ambulance calls in hypothetical nonemergency situations, and questions on the city's emergency medical system. The probit model was used to analyze the data.</p> <p>Results</p> <p>A total of 2,029 out of 3,363 targeted recipients completed the questionnaire (response rate, 60.3%). Probit regression analyses showed that several demographic and socioeconomic factors influence the decision to call an ambulance. Male respondents were more apt than female respondents to state that they would call an ambulance in nonemergency situations (p < 0.05). Age was an important factor influencing the hypothetical decision to call an ambulance (p < 0.05); elderly persons were more apt than younger persons to state that they would call an ambulance. Possession of a car and hesitation to use an ambulance negatively influenced the hypothetical decision to call an ambulance (p < 0.05). Persons who do not have a car were more likely than those with a car to state that they would call an ambulance in unnecessary situations.</p> <p>Conclusion</p> <p>Results of the study suggest that several socioeconomic factors, i.e., age, gender, household income, and possession of a car, influence a person's decision to call an ambulance in nonemergency situations. Hesitation to use an ambulance and knowledge of the city's primary emergency medical center are likely to be important factors limiting ambulance overuse. It was estimated that unnecessary ambulance use is increased approximately 10% to 20% by socioeconomic factors.</p

How local is local? Evidence from bank competition and corporate innovation in U.S.

This paper aims to fill in a research gap in the effects of bank competition on corporate innovation. In addition to the evidence on the favorable effects of bank competition on corporate innovation, we show novel evidence on the substitution effects of bank competition in a wider region and neighbor-state to local bank competition in financing corporate innovation activities. In banking market, we show ‘how local is local’ depends on the operating scope and information transparency of firms. Local banks have an information advantage over distant banks in financing local businesses and informationally opaque corporate innovation activities