Asset prices and portfolio choice with learning from experience

We study asset prices and portfolio choice with overlapping generations, where the young disregard history to learn from own experience. Disregarding history implies less precise estimates of output growth, which in equilibrium leads the young to increase their investment in risky assets after positive returns, that is, they act as trend chasers. In equilibrium, the risk premium decreases after a positive shock and, therefore, trend chasing young agents lose wealth relative to old agents who behave as contrarians. Consistent with findings from survey data, the average belief about the risk premium in the economy relates negatively to future excess returns and is smoother than the true risk premium

Adenylylzyklasen vermittelte Signalgebung in thalamokortikalen Schaltneuronen

Thalamokortikale Netzwerke generieren sowohl normale als auch anomale Muster synchronisierter Aktivität, wie Schlafspindeln und epileptische Spitze-Welle-Entladungen. Tonische Aktivität hingegen herrscht in Phasen der sensorischen Informationsverarbeitung vor. Es wurde bereits gezeigt, dass der intrazelluläre Botenstoff cAMP Ionenkanäle moduliert, welche an der Generierung von thalamokortikaler Aktivität beteiligt sind. Mittels molekularbiologischen und patch clamp-Techniken beleuchtet diese Arbeit das Expressionsprofil von thalamischen Adenylylzyklasen (AC) und die funktionellen Konsequenzen ihrer Aktivierung im Tiermodell der humanen Absence Epilepsie. Es konnte gezeigt werden, dass ACs eine wichtige Funktion bei der Generierung thalamischer Aktivität erfüllen und eine Dysfunktion zur Epileptogenese beitragen kann. Nach AC Aktivierung unterstützt auch die Inhibition der BKCa Kanäle über eine verminderte Frequenzadaptation die 1:1-Weiterleitung von sensorischer Information zum Kortex

Study of the piezoresistivity of doped nanocrystalline silicon thin films

The piezoresistive response of n- and p-type hydrogenated nanocrystalline silicon thin films, deposited by hot-wire (HW) and plasma-enhanced chemical vapor deposition (PECVD) on thermally oxidized silicon wafers, has been studied using four-point bending tests. The piezoresistive gauge factor (GF) was measured on patterned thin-film micro-resistors rotated by an angle θ with respect to the principal strain axis. Both longitudinal (GFL) and transverse (GFT) GFs, corresponding to θ = 0° and 90°, respectively, are negative for n-type and positive for p-type films. For other values of θ (30°, 45°, 120°, and 135°) GFs have the same signal as GFL and GFT and their value is proportional to the normal strain associated with planes rotated by θ relative to the principal strain axis. It is concluded that the films are isotropic in the growth plane since the GF values follow a Mohr’s circle with the principal axes coinciding with those of the strain tensor. The strongest p-type pirezoresistive response (GFL = 41.0, GFT = 2.84) was found in a film deposited by PECVD at a substrate temperature of 250 °C and working pressure of 0.250 Torr, with dark conductivity 1.6 Ω−1cm−1. The strongest n-type response (GFL =− 28.1, GFT =− 5.60) was found in a film deposited by PECVD at 150 °C and working pressure of 3 Torr, with dark conductivity 9.7 Ω−1cm−1. A model for the piezoresistivity of nc-Si is proposed, based on a mean-field approximation for the conductivity of an ensemble of randomly oriented crystallites and neglecting grain boundary effects. The model is able to reproduce the measured GFL values for both n- and p-type films. It fails, however, to explain the transversal GFT data. Both experimental and theoretical data show that nanocrystalline silicon can have an isotropic piezoresistive effect of the order of 40% of the maximum response of crystalline silicon.Fundação para a Ciência e a Tecnologia (FCT) - PTDC/CTM/66558/2006, bolsa de investigação SFRH/BSAB/883/200

Demographische Standards für Deutschland: ein Instrumentenentwurf

Es wird ein Vorschlag für demographische Standards vorgesetllt, der langfristig zu einer Vereinheitlichung der Fragestellungen bei Forschern, Instituten und der amtlichen Statistik führen soll. Der unterschiedlichen Thematik von einzelnen Erhebungen soll dadurch Rechnung getragen werden, daß umfragenspezifische Erweiterungen des vorgeschlagenen Variablensets sowie der Kategoriensysteme möglich sind. Können die vorgeschlagenen Formulierungen aus inhaltlichen oder technischen Gründen nicht verwendet werden, sollten die Fragen so gestellt werden, daß Schnittstellen zu den vorgeschlagenen Kategorien bestehen. (psz

Effect of exposing rams to a female stimulus before semen collection on ram libido and semen quality

peer-reviewedRams with strong libido and desirable semen characteristics can provide more insemination doses per ejaculate and produce more progeny, improving population genetic linkage to improve the accuracy of EBV. The objective of this study was to determine if teasing rams, either by sight and smell alone (Exp. 1), or physical contact (Exp. 2), could improve libido and semen quality of rams. In Exp. 1, there were 3 treatments in which rams were exposed to the sight and smell of the ewe for 1 h: control treatment (n = 5) in which rams were exposed to a ewe not in estrus; non-novel treatment (n = 6) in which rams were exposed to a ewe in estrus and the same ewe was used for semen collection; and novel treatment (n = 6) in which rams were exposed to a ewe in estrus and a different ewe in estrus was used for semen collection. In Exp. 2, rams were individually given full access to a ewe, which had a cotton apron fi tted to cover her vulva, for 15 min. The 3 treatments in Exp. 2 were: control treatment (n = 5) in which rams were placed in a pen with a ewe not in estrus; a nonnovel treatment (n = 5) in which rams were placed in a pen with a ewe in estrus and the same ewe was used for semen collection; novel treatment (n = 6) in which rams were placed in a pen with a ewe in estrus and a different ewe in estrus was used for semen collection. Experiment 1 was repeated for 5 consecutive days and Exp. 2 was repeated for 4 consecutive days. Data on reaction time, number of mounts, semen volume, semen concentration, sperm wave motion, and progressive linear motion (Exp. 1 only) were collected and analyzed as a randomized complete block design, where rams were initially blocked for breed and age. In Exp. 1, there was an effect of day (P < 0.05) and a treatment × day interaction (P < 0.05) on semen volume, whereas there was also an effect of treatment (P < 0.05) and day (P < 0.01) on semen concentration, which was most evident on d 1. In Exp. 2, there was an effect of treatment on reaction time (P < 0.05) and semen volume (P = 0.08), which was most evident on d 1. This study demonstrates an acute effect on d 1 on semen concentration when rams were exposed to the sight and smell of a ewe in estrus. Alternatively, when rams were stimulated with physical contact of a ewe in estrus, an acute increase in semen volume was evident on d 1. These effects were not evident on subsequent days and thus the overall benefi ts on ram libido and semen quality of exposing rams to ewes in estrus are minimal.PUBLISHEDpeer-reviewe

Glufosinate constrains synchronous and metachronous metastasis by promoting anti-tumor macrophages

Abstract Glutamine synthetase (GS) generates glutamine from glutamate and controls the release of inflammatory mediators. In macrophages, GS activity, driven by IL10, associates to the acquisition of M2‐like functions. Conditional deletion of GS in macrophages inhibits metastasis by boosting the formation of anti‐tumor, M1‐like, tumor‐associated macrophages (TAMs). From this basis, we evaluated the pharmacological potential of GS inhibitors in targeting metastasis, identifying glufosinate as a specific human GS inhibitor. Glufosinate was tested in both cultured macrophages and on mice bearing metastatic lung, skin and breast cancer. We found that glufosinate rewires macrophages toward an M1‐like phenotype both at the primary tumor and metastatic site, countering immunosuppression and promoting vessel sprouting. This was also accompanied to a reduction in cancer cell intravasation and extravasation, leading to synchronous and metachronous metastasis growth inhibition, but no effects on primary tumor growth. Glufosinate treatment was well‐tolerated, without liver and brain toxicity, nor hematopoietic defects. These results identify GS as a druggable enzyme to rewire macrophage functions and highlight the potential of targeting metabolic checkpoints in macrophages to treat cancer metastasis

Harmonisation of demographic and socio-economic variables in cross-national survey research

The aim of the present paper is to demonstrate how demographic and socio-economic variables in cross-national comparative survey research can be harmonized. After a short introduction discussing the difference between translation and harmonization, the path from a national concept and structure to an internationally-applicable measurement instrument is traced using the education variable as an example. Tables, References. Adapted from the source document. (author's abstract

Primary breast cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up

The original local lymph node assay (LLNA) is based on the use of radioactive labelling to measure cell proliferation. Other endpoints for the assessment of proliferation are also authorized by the OECD Guideline 429 provided there is appropriate scientific support, including full citations and description of the methodology (OECD, 2002. OECD Guideline for the Testing of Chemicals; Skin Sensitization: Local Lymph Node Assay, Guideline 429. Paris, adopted 24th April 2002.). Here, we describe the outcome of the second round of an inter-laboratory validation of alternative endpoints in the LLNA conducted in nine laboratories in Europe. The validation study was managed and supervised by the Swiss Agency for Therapeutic Products (Swissmedic) in Bern. Ear-draining lymph node (LN) weight and cell counts were used to assess LN cell proliferation instead of [3H]TdR incorporation. In addition, the acute inflammatory skin reaction was measured by ear weight determination of circular biopsies of the ears to identify skin irritation properties of the test items. The statistical analysis was performed in the department of statistics at the university of Bern. Similar to the EC3 values defined for the radioactive method, threshold values were calculated for the endpoints measured in this modification of the LLNA. It was concluded that all parameters measured have to be taken into consideration for the categorisation of compounds due to their sensitising potencies. Therefore, an assessment scheme has been developed which turned out to be of great importance to consistently assess sensitisation versus irritancy based on the data of the different parameters. In contrast to the radioactive method, irritants have been picked up by all the laboratories applying this assessment scheme

Genotyping of Bacillus cereus Strains by Microarray-Based Resequencing

The ability to distinguish microbial pathogens from closely related but nonpathogenic strains is key to understanding the population biology of these organisms. In this regard, Bacillus anthracis, the bacterium that causes inhalational anthrax, is of interest because it is closely related and often difficult to distinguish from other members of the B. cereus group that can cause diverse diseases. We employed custom-designed resequencing arrays (RAs) based on the genome sequence of Bacillus anthracis to generate 422 kb of genomic sequence from a panel of 41 Bacillus cereus sensu lato strains. Here we show that RAs represent a “one reaction” genotyping technology with the ability to discriminate between highly similar B. anthracis isolates and more divergent strains of the B. cereus s.l. Clade 1. Our data show that RAs can be an efficient genotyping technology for pre-screening the genetic diversity of large strain collections to selected the best candidates for whole genome sequencing