25 research outputs found
The Other January Effect: International Evidence
This paper investigates the predictive power of stock market returns in January for the subsequent eleven months' returns across 19 countries, thereby contributing to the literature on stock market seasonalities. Only two out of 19 countries' stock markets exhibit a robust Other January Eect. In light of this evidence, we conclude that the Other January Eect is not an international phenomenon.Stock market efciency, Other January Efect, Stock market anomalies
Do Individual Index Futures Investors Destabilize the Underlying Spot Market?
This paper investigates the impact of introducing index futures trading on the volatility of the underlying stock market. We exploit a unique institutional setting in which presumably uninformed individuals are the dominant trader type in the futures markets. This enables us to investigate the destabilization hypothesis more accurately than previous studies do and to provide evidence for or against the in
uence of individuals trading in index futures on spot market volatility. To overcome econometric shortcomings of the existing literature we employ a Markov-switching-GARCH approach to endogenously identify distinct volatility regimes. Our empirical evidence for Poland surprisingly suggests that the introduction of index futures trading does not destabilize the spot market. This nding is robust across 3 stock market indices and is corroborated by further analysis of a control group.Individual Investors, Uninformed Trading, Stock Index Futures, Emerging Capital Markets, Stock Market Volatility, Markov-Switching-GARCH Model
Testing the Water–Energy Theory on American Palms (Arecaceae) Using Geographically Weighted Regression
Water and energy have emerged as the best contemporary environmental correlates of broad-scale species richness patterns. A corollary hypothesis of water–energy dynamics theory is that the influence of water decreases and the influence of energy increases with absolute latitude. We report the first use of geographically weighted regression for testing this hypothesis on a continuous species richness gradient that is entirely located within the tropics and subtropics. The dataset was divided into northern and southern hemispheric portions to test whether predictor shifts are more pronounced in the less oceanic northern hemisphere. American palms (Arecaceae, n = 547 spp.), whose species richness and distributions are known to respond strongly to water and energy, were used as a model group. The ability of water and energy to explain palm species richness was quantified locally at different spatial scales and regressed on latitude. Clear latitudinal trends in agreement with water–energy dynamics theory were found, but the results did not differ qualitatively between hemispheres. Strong inherent spatial autocorrelation in local modeling results and collinearity of water and energy variables were identified as important methodological challenges. We overcame these problems by using simultaneous autoregressive models and variation partitioning. Our results show that the ability of water and energy to explain species richness changes not only across large climatic gradients spanning tropical to temperate or arctic zones but also within megathermal climates, at least for strictly tropical taxa such as palms. This finding suggests that the predictor shifts are related to gradual latitudinal changes in ambient energy (related to solar flux input) rather than to abrupt transitions at specific latitudes, such as the occurrence of frost
Biodiversity and the Functioning of Ecosystems in the Age of Global Change: Integrating Knowledge Across Scales
The dramatic decline of biodiversity worldwide has raised a general concern on the impacts this process could have for the well-being of humanity. Human societies strongly depend on the benefits provided by natural ecosystems, which are the result of biogeochemical processes governed by species activities and their interaction with abiotic compartments. After decades of experimental research on the biodiversity-functioning relationship, a relative agreement has been reached on the mechanisms underlying the impacts that biodiversity loss can have on ecosystem processes. However, a general consensus is still missing. We suggest that the reason preventing an integration of existing knowledge is the scale discrepancy between observations on global change impacts and biodiversity-functioning experiments. The present chapter provides an overview of global change impacts on biodiversity across various ecological scales and its consequences for ecosystem functioning, highlighting what is known and where knowledge gaps still persist. Furthermore, the reader will be introduced to a set of tools that allow a multi-scale analysis of how global change drivers impact ecosystem functioning
Clinical characteristics of women captured by extending the definition of severe postpartum haemorrhage with 'refractoriness to treatment': a cohort study
Background: The absence of a uniform and clinically relevant definition of severe postpartum haemorrhage
hampers comparative studies and optimization of clinical management. The concept of persistent postpartum
haemorrhage, based on refractoriness to initial first-line treatment, was proposed as an alternative to common
definitions that are either based on estimations of blood loss or transfused units of packed red blood cells
(RBC). We compared characteristics and outcomes of women with severe postpartum haemorrhage captured
by these three types of definitions.
Methods: In this large retrospective cohort study in 61 hospitals in the Netherlands we included 1391 consecutive
women with postpartum haemorrhage who received either ≥4 units of RBC or a multicomponent transfusion. Clinical
characteristics and outcomes of women with severe postpartum haemorrhage defined as persistent postpartum
haemorrhage were compared to definitions based on estimated blood loss or transfused units of RBC within 24 h
following birth. Adverse maternal outcome was a composite of maternal mortality, hysterectomy, arterial embolisation
and intensive care unit admission.
Results: One thousand two hundred sixty out of 1391 women (90.6%) with postpartum haemorrhage fulfilled the
definition of persistent postpartum haemorrhage. The majority, 820/1260 (65.1%), fulfilled this definition within 1 h
following birth, compared to 819/1391 (58.7%) applying the definition of ≥1 L blood loss and 37/845 (4.4%) applying
the definition of ≥4 units of RBC. The definition persistent postpartum haemorrhage captured 430/471 adverse maternal
outcomes (91.3%), compared to 471/471 (100%) for ≥1 L blood loss and 383/471 (81.3%) for ≥4 units of RBC. Persistent
postpartum haemorrhage did not capture all adverse outcomes because of missing data on timing of initial, first-line
treatment.
Conclusion: The definition persistent postpartum haemo
Positive feedback trading in stock index futures: International evidence
Using a simple intertemporal asset pricing model with heterogeneous agents, this paper addresses the issue of trend-chasing investor behavior in stock index futures markets. There is strong evidence of positive feedback trading in the majority of 32 emerging and mature markets. Trend-chasing appears most pronounced after price drops during periods of financial crisis. Our empirical findings are of great concern for investors who want to use index futures as an instrument to hedge risk or exploit arbitrage opportunities. They also have implications for the debate on destabilizing effects of futures trading.Stock index futures Heterogeneous agents Feedback trading Hedging Market efficiency
Preparation of metal-SAM-dendrimer-SAM-metal junctions by supramolecular metal transfer printing
Metal-self-assembled monolayer (SAM)-dendrimer-SAM-metal junctions were prepared by a new type of metal transfer printing (mTP) that uses multiple ß-cyclodextrin (ßCD) host-guest interactions between a metal-coated stamp decorated with a monolayer of host molecules and a substrate which is functionalized with the same host molecules. Metal transfer from the stamp to the substrate is mediated by multivalent guest molecules, immobilized at either the host-functionalized stamp or the substrate, which act as a supramolecular glue. A ßCD SAM was formed at thin Au films that were deposited onto PDMS stamps. Conformal contact of these functionalized PDMS stamps with redox-active monolayers of different generations of ferrocenyl- (Fc-) and biferrocenyl- (BFc-) terminated dendrimers, or redox-inactive monolayers of adamantyl- (Ad-) terminated dendrimers adsorbed at ßCD SAMs (molecular printboards) resulted in transfer of the Au from the PDMS stamp to the substrate. ßCD SAMs at different substrates were used, e.g. Au and SiO2. Also transfer of metal to SiO2 surfaces was possible owing to electrostatic interactions between the positively charged dendrimers and the SiO2 substrate. Various types of metal patterns were transferred, such as dots, squares or lines with dimensions varying from 5 µm to 50 µm. Lines of 10 µm width and as long as 10 mm could be faithfully transferred
Preparation of metal-SAM-dendrimer-SAM-metal junctions by supramolecular metal transfer printing
Metal-self-assembled monolayer (SAM)-dendrimer-SAM-metal junctions were prepared by a new type of metal transfer printing (mTP) that uses multiple -cyclodextrin ( CD) host-guest interactions between a metal-coated stamp decorated with a monolayer of host molecules and a substrate which is functionalized with the same host molecules. Metal transfer from the stamp to the substrate is mediated by multivalent guest molecules, immobilized at either the hostfunctionalized stamp or the substrate, which act as a supramolecular glue . A CD SAM was formed at thin Au films that were deposited onto PDMS stamps. Conformal contact of these functionalized PDMS stamps with redox-active monolayers of different generations of ferrocenyl-(Fc-) and biferrocenyl-(BFc-) terminated dendrimers, or redox-inactive monolayers of adamantyl-(Ad-) terminated dendrimers adsorbed at CD SAMs ( molecular printboards ) resulted in transfer of the Au from the PDMS stamp to the substrate. CD SAMs at different substrates were used, e.g. Au and SiO 2 . Also transfer of metal to SiO 2 surfaces was possible owing to electrostatic interactions between the positively charged dendrimers and the SiO 2 substrate. Various types of metal patterns were transferred, such as dots, squares or lines with dimensions varying from 5 µm to 50 µm. Lines of 10 µm width and as long as 10 mm could be faithfully transferred
The German Focus on the Outcomes of Communication Under Six (FOCUS-G): Reliability and Validity of a Novel Assessment of Communicative Participation
Purpose: Our purpose was to explore the validity and reliability of the German Focus on the Outcomes of Communication Under Six (FOCUS-G; Thomas-Stonell, Oddson, Robertson, & Rosenbaum, 2010, 2012), which is an authorized adaptation of the Focus on the Outcomes of Communication Under Six (Thomas-Stonell et al., 2010) tool, which measures communicative participation in preschool children. Method: Parents of typically developing children (TDC) and of children with speech impairment (CSI) completed the FOCUS-G and the Questionnaire for Measuring Health-Related Quality of Life in Children (KiddyKINDL; Ravens-Sieberer & Bullinger, 2000). To determine test-retest reliability, the FOCUS-G was readministered to a subsample of parents 1 week later. Results: The FOCUS-G had high values for internal consistency (alpha =.959, Omega =.941), test-retest reliability (intraclass correlation coefficient =.974), and split-half reliability (r =.832). Total scores on the FOCUS-G and KiddyKINDL demonstrated significant associations. FOCUS-G total scores and subdomain scores for both samples showed significant correlations, indicating good construct validity. The discriminatory ability of the FOCUS-G was indicated by significantly higher mean scores for TDC (M = 6.03, SD = 0.65) than CSI (M = 5.47, SD = 1.02). Conclusion: The overall good psychometric properties of this novel assessment of communicative participation support its use by speech-language pathologists for clinical and research purposes with German-speaking children