Measuring Half-Lives Using A Non-Parametric Bootstrap Approach

In this paper we extend the Murray and Papell (2002) study by using a non-parametric bootstrap approach which allows for non-normality, and focusing on quarterly real exchange rate in twenty OECD countries in the post-1973 floating period. We run Augmented Dickey-Fuller (ADF) regressions, and estimate the half-lives (and confidence intervals) from the corresponding impulse response functions. Further, we use an approximately median-unbiased estimator of the autoregressive parameters, and report the implied point estimates and confidence intervals. We find that accounting for nonnormality results in even higher estimates of the degree of persistence of PPP deviations, but, as in Murray and Papell (2002), the confidence intervals are so wide that no strong conclusions are warranted on the existence of a PPP puzzle

An investigation of customer order flow in the foreign exchange market

This paper examines the effect that heterogeneous customer orders flows have on exchange rates by using a new, and the largest, proprietary dataset of weekly net order flow segmented by customer type across nine of the most liquid currency pairs. We make several contributions. Firstly, we investigate the extent to which customer order flow can help to explain exchange rate movements over and above the influence of macro-economic variables. Secondly, we address the issue of whether order flows contain (private) information which explain exchange rates changes. Thirdly, we look at the usefulness of order flow in forecasting exchange rate movements at longer horizons than those generally considered in the micro-structure literature. Finally we address the question of whether the out-of-sample exchange rate forecasts generated by order flows can be employed profitably in the foreign exchange markets

Etiological diagnosis, prognostic significance and role of electrophysiological study in patients with Brugada ECG and syncope.

BACKGROUND: Syncope is considered a risk factor for life-threatening arrhythmias in Brugada patients. Distinguishing a benign syncope from one due to ventricular arrhythmias is often difficult, unless an ECG is recorded during the episode. Aim of the study was to analyze the characteristics of syncopal episodes in a large population of Brugada patients and evaluate the role of electrophysiological study (EPS) and the prognosis in the different subgroups. METHODS AND RESULTS: One hundred ninety-five Brugada patients with history of syncope were considered. Syncope were classified as neurally mediated (group 1, 61%) or unexplained (group 2, 39%) on the basis of personal and family history, clinical features, triggers, situations, associated signs, concomitant therapy. Most patients underwent EPS; they received ICD or implantable loop-recorder on the basis of the result of investigations and physician's judgment. At 62±45months of mean follow-up, group 1 showed a significantly lower incidence of arrhythmic events (2%) as compared to group 2 (9%, p<0.001). Group 2 patients with positive EPS showed the highest risk of arrhythmic events (27%). No ventricular events occurred in subjects with negative EPS. CONCLUSION: Etiological definition of syncope in Brugada patients is important, as it allows identifying two groups with different outcome. Patients with unexplained syncope and ventricular fibrillation induced at EPS have the highest risk of arrhythmic events. Patients presenting with neurally mediated syncope showed a prognosis similar to that of the asymptomatic and the role of EPS in this group is unproven

Separation of realized ecological niche axes among sympatric tilefishes provides insight into potential drivers of co-occurrence in the NW Atlantic

Golden and Blueline Tilefish (Lopholatilus chamaeleonticeps and Caulolatilus microps) are keystone taxa in northwest (NW) Atlantic continental shelf-edge environments due to their biotic (trophic-mediated) and abiotic (ecosystem engineering) functional roles combined with high-value fisheries. Despite this importance, the ecological niche dynamics (i.e., those relating to trophic behavior and food-web interactions) of these sympatric species are poorly understood, knowledge of which may be consequential for maintaining both ecosystem function and fishery sustainability. We used stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) to build realized ecological niche hypervolumes to serve as proxies for diet and production use patterns of L. chamaeleonticeps and C. microps. We hypothesized that: (a) species exhibit ontogenetic shifts in diet and use of production sources; (b) species acquire energy from spatially distinct resource pools that reflect a sedentary life-history and differential use of the continental shelf-edge; and (c) species exhibit differentiation in one or more measured niche axes. We found evidence for ontogenetic shifts in diet (δ15N) but not production source (δ13C) in both species, suggesting a subtle expansion of measured ecological niche axes. Spatial interpolation of stable isotope ratios showed distinct latitudinal gradients; for example, individuals were 13C enriched in northern and 15N enriched in southern regions, supporting the assertion that tilefish species acquire energy from regional resource pools. High isotopic overlap was observed among species (≥82%); however, when hypervolumes included depth and region of capture, overlap among species substantially decreased to overlap estimates of 15%–77%. This suggests that spatial segregation could alleviate potential competition for resources among tilefish species inhabiting continental shelf-edge environments. Importantly, our results question the consensus interpretation of isotopic overlap estimates as representative of direct competition among species for shared resources or habitats, instead identifying habitat segregation as a possible mechanism for coexistence of tilefish species in the NW Atlantic

Oxidative inactivation of SARS-CoV-2 on photoactive AgNPs@Tio2 ceramic tiles

The current SARS-CoV-2 pandemic causes serious public health, social, and economic issues all over the globe. Surface transmission has been claimed as a possible SARS-CoV-2 infection route, especially in heavy contaminated environmental surfaces, including hospitals and crowded public places. Herein, we studied the deactivation of SARS-CoV-2 on photoactive AgNPs@TiO2 coated on industrial ceramic tiles under dark, UVA, and LED light irradiations. SARS-CoV-2 inactivation is effective under any light/dark conditions. The presence of AgNPs has an important key to limit the survival of SARS-CoV-2 in the dark; moreover, there is a synergistic action when TiO2 is decorated with Ag to enhance the virus photocatalytic inactivation even under LED. The radical oxidation was confirmed as the the central mechanism behind SARS-CoV-2 damage/inactivation by ESR analysis under LED light. Therefore, photoactive AgNPs@TiO2 ceramic tiles could be exploited to fight surface infections, especially during viral severe pandemics

Evolution of realized Eltonian niches across Rajidae species

The notion that closely related species resemble each other in ecological niche space (i.e., phylogenetic dependence) has been a long-standing, contentious paradigm in evolutionary biology, the incidence of which is important for predicting the ecosystem-level effects of species loss. Despite being examined across a multitude of terrestrial taxa, many aspects of niche conservatism have yet to be explored in marine species, especially for characteristics related to resource use and trophic behavior (Eltonian niche characteristics, ENCs). We combined ENCs derived from stable isotope ratios at assemblage- and species-levels with phylogenetic comparative methods, to test the hypotheses that benthic marine fishes (1) exhibit similar assemblage-wide ENCs regardless of geographic location and (2) display phylogenetically dependent ENCs at the species level. We used a 12-species sub-set of the monophyletic group Rajidae sampled from three independent assemblages (Central California, Gulf of Alaska, and Northwest Atlantic), which span two ocean basins. Assemblage-level ENCs implied low trophic diversity and high evenness, suggesting that Rajidae assemblages may exhibit a well-defined trophic role, a trend consistent regardless of geographic location. At the species level, we found evidence for phylogenetic dependence of ENCs relating to trophic diversity (i.e., isotopic niche width; SEAc). Whether individuals can be considered functional equivalents across assemblages is hard to ascertain because we did not detect a significant phylogenetic signal for ENCs relating to trophic function (e.g., trophic position). Thus, additional, complimentary approaches are required to further examine the phylogenetic dependence of species functionality. Our approach illustrates the potential of stable isotope-derived niche characteristics to provide insight on macroecological processes occurring across evolutionary time, which could help predict how assemblages may respond to the effects of species loss

Indole-based perenosins as highly potent HCl transporters and potential anti-cancer agents

Prodigiosin is one of the most potent anion transporters in lipid bilayer membranes reported to date. Inspired by the structure of this natural product, we have recently designed and synthesised a new class of H+/Cl− cotransporters named 'perenosins'. Here we report a new library of indole-based perenosins and their anion transport properties. The new transporters demonstrated superior transmembrane transport efciency when compared to other indole-based transporters, due to favourable encapsulating efects from the substituents on the perenosin backbone. Anion transport assays were used to determine the mechanism of chloride transport revealing that the compounds function as 'strict' HCl cotransporters. Cell viability studies showed that some compounds specifcally trigger lateonset cell death after 72h with a unique correlation to the position of alkyl chains on the perenosins. Further investigations of cell death mechanism showed a mixture of cell cycle arrest and apoptosis was responsible for the observed decrease in cell viability

Involvement of RET oncogene in human tumours: specificity of RET activation to thyroid tumours.

Non-thyroid neoplasia were analysed by Southern blot of genomic DNA and DNA prepared by reverse transcription and amplification by polymerase chain reaction (RT/PCR) for the activation of the RET oncogene. It is known that the rearrangement of RET occurs in about 10%-20% of human thyroid papillary carcinomas. None of 528 non-thyroid tumours showed rearrangement of the RET proto-oncogene, whereas three out of 30 thyroid papillary carcinomas were positive for RET activation. Therefore the activation of RET seems to be a somatic cell mutation specific to human thyroid carcinomas