Search results for " Timing"
showing 10 items of 87 documents
Timing of surgery following SARS-CoV-2 infection: an international prospective cohort study
2021
Peri-operative SARS-CoV-2 infection increases postoperative mortality. The aim of this study was to determine the optimal duration of planned delay before surgery in patients who have had SARS-CoV-2 infection. This international, multicentre, prospective cohort study included patients undergoing elective or emergency surgery during October 2020. Surgical patients with pre-operative SARS-CoV-2 infection were compared with those without previous SARS-CoV-2 infection. The primary outcome measure was 30-day postoperative mortality. Logistic regression models were used to calculate adjusted 30-day mortality rates stratified by time from diagnosis of SARS-CoV-2 infection to surgery. Among 140,231…
Delayed and incomplete treatment may result in dural fistula development in children with Vein of Galen malformation
2017
The association of dural arteriovenous fistulas (DAVF) in children with Vein of Galen malformation (VGM) has recently been reported for the first time. In a larger series of cases treated with transarterial NBCA embolization, 30% had DAVF. We wanted to analyze the development of DAVF in our cohort of children with VGM and to evaluate whether their occurrence depends on different treatment timing and embolic materials. We analyzed 43 VGM cases treated with a combined transarterial and transvenous approach between 2003 and 2016. In our early series until 2011, we used coils solely in 21 children. Since 2012, 22 children were treated with the combination of coils and Onyx. In the early series…
Embodiment and the origin of interval timing : kinematic and electromyographic data
2016
International audience; Recent evidence suggests that interval timing (the judgment of durations lasting from approximately 500 ms. to a few minutes) is closely coupled to the action control system. We used surface electromyography (EMG) and motion capture technology to explore the emergence of this coupling in 4-, 6-, and 8-month-olds. We engaged infants in an active and socially relevant arm-raising task with seven cycles and response period. In one condition, cycles were slow (every 4 s); in another, they were fast (every 2 s). In the slow condition, we found evidence of time-locked sub-threshold EMG activity even in the absence of any observed overt motor responses at all three ages. Th…
Endogenous timing with infinitely many firms
2008
Abstract A model with constant marginal costs is considered where firms choose first a period for production and then the amount to produce when competing in the market according to the resulting timing decisions. Multiple equilibria arise allowing for infinitely many industry output configurations encompassing one limit-output dominant firm and the Cournot equilibrium with free entry as extreme cases. At each of these equilibria a firm produces a positive amount only if this firm commits to produce at period one. Both Stackelberg and Cournot-like outcomes are sustainable as equilibria however. When the number of leaders is given, production at subsequent periods is always prevented, and in…
Fooled by Data-Mining: The Real-Life Performance of Market Timing with Moving Averages
2013
In this paper, we revisit the myths regarding the superior performance of market timing strategies based on moving average and time-series momentum rules. These active timing strategies are very appealing to investors because of their extraordinary simplicity and because they promise substantial advantages over their passive counterparts (see, for example, the paper by M. Faber (2007) "A Quantitative Approach to Tactical Asset Allocation" published in the Journal of Wealth Management). However, the ``too good to be true" reported performance of these market timing rules raises a legitimate concern as to whether this performance is realistic and whether investors can expect that future perfo…
Market Timing with Moving Averages: Anatomy and Performance of Trading Rules
2015
The underlying concept behind the technical trading indicators based on moving averages of prices has remained unaltered for more than half of a century. The development in this field has consisted in proposing new ad-hoc rules and using more elaborate types of moving averages in the existing rules, without any deeper analysis of commonalities and differences between miscellaneous choices for trading rules and moving averages. The first contribution of this paper is to uncover the anatomy of market timing rules with moving averages. Our analysis offers a new and very insightful reinterpretation of the existing rules and demonstrates that the computation of every trading indicator can equiva…
Spin up and phase fluctuations in the timing of the accreting millisecond pulsar XTE J1807-294
2007
We performed a timing analysis of the 2003 outburst of the accreting X-ray millisecond pulsar XTE J1807-294 observed by RXTE. Using recently refined orbital parameters we report for the first time a precise estimate of the spin frequency and of the spin frequency derivative. The phase delays of the pulse profile show a strong erratic behavior superposed to what appears as a global spin-up trend. The erratic behavior of the pulse phases is strongly related to rapid variations of the light curve, making it very difficult to fit these phase delays with a simple law. As in previous cases, we have therefore analyzed separately the phase delays of the first harmonic and of the second harmonic of …
Endogenous R&D Symmetry in Linear Duopoly with One-way Spillovers
2005
A duopoly model of cost reducing R&D-Cournot market competition is extended to encompass endogenous timing of R&D investments. Under the assumption that R&D spillovers are zero under simultaneous choices of R&D and only flow from the R&D leader to the follower under sequential choices, sequential and simultaneous play at the R&D stage are compared in order to assess the role of technological externalities in stimulating or attenuating endogenous firm asymmetry. The only timing structure of the R&D stage sustainable as subgame–perfect Nash equilibrium involves simultaneous play and thus zero spillovers.
Ozone therapy in idiopathic carpal tunnel syndrome. Biochemical, neurophysiological and clinical aspects
2018
Purpose.
 Idiopathic Carpal Tunnel Syndrome (CTS) is the most common entrapment neuropathy; however few and only retrospective studies have been found in search engines about Ozone Therapy. 
 The aim of this paper was to evaluate clinical and neurophysiological outcome following Ozone Therapy in CTS.
 We focused the attention on the evidences concerning the role of Subsynovial Connective Tissue (SSCT) in the pathogenesis of CTS and the ozone pre-conditioning effects linked to pain and inflammatory pathways and to fibrosis induced by Ischemia-Reperfusion Injury.
 
 Materials and methods.
 Thirty-five patients, aged between 21 and 80, were stratified clinically b…
Neural networks engaged in milliseconds and seconds time processing: evidence from transcranial magnetic stimulation and patients with cortical or su…
2009
Here, we review recent transcranial magnetic stimulation studies and investigations in patients with neurological disease such as Parkinson's disease and stroke, showing that the neural processing of time requires the activity of wide range-distributed brain networks. The neural activity of the cerebellum seems most crucial when subjects are required to quickly estimate the passage of brief intervals, and when time is computed in relation to precise salient events. Conversely, the circuits involving the striatum and the substantia nigra projecting to the prefrontal cortex (PFC) are mostly implicated in supra-second time intervals and when time is processed in conjunction with other cognitiv…