The handling of numerical ages and their random uncertainties

Die korrekte Auswertung numerischer Alter mit ihren Plus-Minus-„Fehlerangaben“ oder besser Standardabweichungen und die Anwendung der damit verbundenen statistischen Auswerteverfahren sind für Geowissenschaftler und Geographen oft eine schwierige Aufgabe, weil ihnen dafür die Ausbildung fehlt. Entsprechend finden sich in der Literatur viele nur schwer nachvollziehbare geochronologische Folgerungen. Sie können allerdings auch dann falsch sein, wenn sie sich auf Ergebnisse aus Datenbanken ohne ausreichende Angaben über den Ursprung des datierten Materials und die angewandten analytischen Techniken beziehen. Diese Arbeit führt in die Beurteilung und Handhabung numerischer Altersangaben ein. Mit ihr können elementare Rechnungen und einfache statistische Tests korrekt ausgeführt werden. Entsprechende Beispiele veranschaulichen den Weg dazu. Die mit der Visualisierung von numerischen Altern in Form von einfachen und Dispersions-Histogrammen verbundenen Probleme werden diskutiert.researc

Sind Veröffentlichungen von publikationspflichtigen Unternehmensmeldungen faktorbasierte Marktrisiken? Eine Untersuchung von Noise-Trader-Risiken und Noise-Trader-Heuristiken

This thesis is intended to contribute to a further understanding of noise trader risk. It is examined whether company announcements subject to disclosure requirements contribute to cross-sectional Noise Trader risk. If prices are inefficient the Behavioral Asset-Pricing Model (BAPM) developed by Shefrin and Statman postulates a noise trading risk premium. A theoretical analysis reveals, that the abnormal expected return is an aggregated risk, including risk factors momentum, value and beta factor. Size approximates beta factor, eliminates momentum and weakens value. The Information-Adjusted Noise Model developed by Ramiah and Davidson is modified to capture time shifted as well as cross-sectional responses to company announcements. The responses to disclosures of annual financial reports and dividend announcements are classified as Noise Trading risk factors. They are delayed by one to two days and significantly correlated with beta-correction changes in market disequilibrium. The disclosures of dividend announcements might be proxy for an underlying risk factor caused by opinions shared on general annual meetings and investment of dividend payments. The disclosures of annual financial reports are related to book-to-market and momentum indicating similar risk factors to Fama French three-factor model and Carhart four-factor model, which might be caused by not recognizing inefficient market conditions by the Information Trader. The Information Trader think they are still trading on information, although they are trading on noise. Homogenous expectations synchronize effects on stock prices and create the observed risk factors. This concept of a collectively temporarily metamorphose of the Information Trader might explain same results from a neoclassical and a behavioral perspective. Investing in Noise Trader risk can be realized by combining the BAMP with zero-beta CAPM developed by Black. The zero-beta BAPM enables a risk-based Asset Allocation and is superior to zero-beta CAPM, because correlations with stocks not belonging to the portfolio are considered. Short selling of the zero-beta portfolio to finance a long position in the efficient portfolio enables a Factor Investing investment strategy. This portfolio meets all assumptions of Behavioral Portfolio Theory with multiple mental accounts (BPT-MA) developed by Shefrin and Statman

The role of contact guidance on cancer metastasis

Cancer cell metastasis is responsible for approximately 90% of deaths related to cancer. The migration of cancer cells away from the primary tumor and into healthy tissue is driven in part by contact guidance, or directed migration in response to aligned extracellular matrix. While contact guidance has been a focus of many studies, much of this research has explored environments that present 2D contact guidance structures. Contact guidance environments in 3D more closely resemble in vivo conditions and model cell-ECM interactions better than 2D environments. We have developed a simple rotational alignment technique which allows for the study of cancer cells response to contact guidance in collagen fiber gels. MDA-MB-231 (mesenchymal) and MTLn3 (amoeboid) cells. MDA-MB-231 cells migrate with high directional fidelity in aligned collagen gels, while MTLn3 cells show no directional migration. The collagen stiffness was increased through glycation, resulting in decreased MDA-MB-231 directionality in aligned collagen gels. Interestingly, partial inhibition of cell contractility dramatically decreased directionality in MDA-MB-231 cells. The directionality of MDA-MB-231 cells was most sensitive to ROCK inhibition, but unlike in 2D contact guidance environments, cell directionality and speed are more tightly coupled. Modulation of the contractile apparatus appears to more potently affect contact guidance than modulation of extracellular mechanical properties of the contact guidance cue. Pancreatic cancer has one of the lowest 5 year survival rates (3-5%), which is, in part, due to poor diagnostics and treatment options. Recently, aligned fibers have been seen oriented away from the edge of the tumor within the pancreas. This suggests that contact guidance, directional migration in response to aliened ECM fibers, may be critical to the early stages of metastasis. Communication between pancreatic cancer (PC) and pancreatic stellate (PS) cells under contact guidance were chosen to study in the aligned fiber field. PS cells migrated directionally in monoculture, however when co-cultured the directionally vanished. PC cells never showed contact guidance. Mucin 4 is a large glycoprotein which is a known communication modulator overexpressed in pancreatic cancer The MUC4 gene was knocked out of the PC cells (PC muc4 KO) which resulted a return of directionality to the PS cells but still did not produce contact guidance within the PC cells when co-cultured. Co-culturing PS and both PC cells always resulted in faster cell speeds. Second Harmonic Generation was used to investigate collage reorganization. PS and PC cells, when monocultured and co-cultured with each other, resulted in enhanced collagen fiber alignment. PC muc4 KO, when monoculutred or co-cultured with PS cells, did not alter the alignment or disrupted it and returned it to an unaligned state. F-actin intensity and MMP activity were shown to be higher in co-cultured systems. When F-actin was inhibited in co-culture conditions, alignment was neither enhanced nor disrupted. When MMP-14 was inhibited in PS+PC conditions alignment, was disrupted and returned to an unaligned state. When MMP-14 was inhibited in PS+PC muc4 KO conditions, alignment was neither enhanced nor disrupted. Hyaluronan (HA), a polysaccharide found to be overproduced within the pancreatic tumor, was added to the collagen gels to study how the presence of HA effects contact guidance in pancreatic cancer (PC) and pancreatic stellate (PS) cells. Mucin 4 is a large glycoprotein which is can block binding of cells to HA and is overexpressed in pancreatic cancer. The MUC4 gene was knocked out of the PC cells (PC muc4 KO) to investigate how mucin 4 may affect HA bonding. In the presence of HA, PS cells showed a slight increase in speed and directionality. Surprisingly, PC and PC muc4 KO cells showed directional migration in response to aligned fibers, which has not previously been seen. Further protrusion analysis revealed that the ratio of I to Y extensions was inversely proportional to cellular speed. Low molecular weight HA (LMW HA) is believed to be important during the early stages of invasion within the pancreases, so the molecular weight was decreased but concentration kept the same. Migration speed and directionality remained consistent while motility coefficient ratio median increased significantly. This indicates persistence time may be important and regulated by LMW HA

Late-glacial and early Holocene lake sediments, ground-water formation and climate in the Atacama Altiplano 22–24°S

Precipitation rates in the Atacama Altiplano 22–24°S were 400–500 mm yr−1 during late glacial and early Holocene times as opposed to 200 mm yr−1 today. This humid phase (Tauca phase) was likely due to strengthened tropical (monsoonal) circulation, which brought continental moisture to the Atacama Altiplano. The lake level of Laguna Lejía (23°30′S, 4350 m) at that time was up to 25 m higher than it is today. Mg/Ca and Sr/Ca data from lake sediments show that, what today is a highly saline lake was a freshwater lake at that time. Seasonally-laminated calcareous sediments were deposited between 13 500 and <10 400 yr B.P. indicating the maximum of the humid phase. Climatic changes in the past are important for current groundwater resources.14C and3H data from lake-, ground- and well water suggest that modern groundwater formation (i.e. water <40 years) in the Altiplano is very limited under current arid conditions. We conclude that significant amounts of the water resources in this area originated during the time of the late-glacial and early Holocene humid climate. Tritium data from snow samples show that the moisture in the Altiplano at 22–24°S is mainly of continental origin, whereas precipitation from the westerlies hardly contributes to the water supply in this area. This precipitation pattern matches the paleodata, and we suggest that current precipitation formation may provide an analogue framework for late-glacial circulation in this area

Dogville e Brecht: o teatro no cinema

Análise do filme Dogville (2003) para efeito de comparação com os recursos teatrais empregados pelo dramaturgo e teatrólogo Bertolt Brecht (1898-1956) em seu Teatro Épico. O que está em jogo é a comprovação de uma ideia difundida no meio cinematográfico que tal movimento teatral se configurou na principal influência do diretor do longa-metragem, o dinamarquês Lars Von Trier (1956 - ). Através do estudo de O Pequeno Organon para o Teatro, espécie de manifesto escrito por Brecht, e assim conhecendo os pilares do Teatro Épico, realiza-se um estudo comparativo com elementos do filme, como narrativa direção de arte e atuação do elenco. Busca-se encontrar diferenças e pontos de intersecção entre as duas obras, para reafirmar ou desmentir o que se afirma na mídia sobre Dogville, como no caso dos blogs destinados a comentar sobre cinema. Observa-se, através desse trabalho a aproximação cada vez mais comum entre cinema e teatro, sendo efetuada, nesse caso, em sua forma mais ousada. E a forma como e harmonizam os dois tipos de arte no que foi chamado por Lars Von Trier de “Cinema de Fusão”

Rotavirus-Associated Necrotizing Enterocolitis After Cardiac Catheterization in Infants

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72446/1/j.1540-8183.1991.tb01020.x.pd

Transmission routes of African swine fever virus to domestic pigs: current knowledge and future research directions

African swine fever (ASF) is a major threat to the pig industry in Europe. Since 2007, ASF outbreaks have been ongoing in the Caucasus, Eastern Europe and the Baltic countries, causing severe economic losses for many pig farmers and pork producers. In addition, the number of ASF cases in wild boar populations has dramatically increased over the past few years. Evidence supports direct contact with infectious domestic pigs and wild boars, and consumption of contaminated feed, as the main transmission routes of ASF virus (ASFV) to domestic pigs. However, significant knowledge gaps highlight the urgent need for research to investigate the dynamics of indirect transmission via the environment, the minimal infective doses for contaminated feed ingestion, the probability of effective contacts between infectious wild boars and domestic pigs, the potential for recovered animals to become carriers and a reservoir for transmission, the potential virus persistence within wild boar populations and the influence of human behaviour for the spread of ASFV. This will provide an improved scientific basis to optimise current interventions and develop new tools and strategies to reduce the risk of ASFV transmission to domestic pigs.ISSN:0042-490