Statistical Picking of Multivariate Waveforms.

In this paper, we propose a new approach based on the fitting of a generalized linear regression model in order to detect points of change in the variance of a multivariate-covariance Gaussian variable, where the variance function is piecewise constant. By applying this new approach to multivariate waveforms, our method provides simultaneous detection of change points in functional time series. The proposed approach can be used as a new picking algorithm in order to automatically identify the arrival times of P- and S-waves in different seismograms that are recording the same seismic event. A seismogram is a record of ground motion at a measuring station as a function of time, and it typically records motions along three orthogonal axes (X, Y, and Z), with the Z-axis being perpendicular to the Earth's surface and the X- and Y-axes being parallel to the surface and generally oriented in North-South and East-West directions, respectively. The proposed method was tested on a dataset of simulated waveforms in order to capture changes in the performance according to the waveform characteristics. In an application to real seismic data, our results demonstrated the ability of the multivariate algorithm to pick the arrival times in quite noisy waveforms coming from seismic events with low magnitudes.

Vascular Risk Factors, Vascular Diseases, and Imaging Findings in a Hospital-based Cohort of Mild Cognitive Impairment Types.

BACKGROUND: Mild Cognitive Impairment (MCI) is a transitional state between normal cognition and dementia. OBJECTIVE: The aim of this study is to investigate the role of vascular risk factors, vascular diseases, cerebrovascular disease and brain atrophy in a large hospital-based cohort of MCI types including 471 amnestic MCI (a-MCI), 693 amnestic MCI multiple domain (a-MCImd), 322 single non-memory MCI (snm-MCI), and 202 non amnestic MCI multiple domain (na-MCImd). For comparison, 1,005 neurologically and cognitively healthy subjects were also evaluated. METHOD: Several vascular risk factors and vascular diseases were assessed. All participants underwent neurological, neuropsychological and behavioural assessments as well as carotid ultrasonography and standard brain MRI. Multinomial logistic regression models on the MCI cohort with the NCH group and a-MCI type as reference categories were used to assess the effects of the variables evaluated on the estimated probability of one of the four MCI types. RESULTS: This study demonstrates that cerebrovascular disease contributes substantially to the risk of non-memory MCI types and a-MCImd type, and that brain atrophy is present in all MCI types and is greater in multiple domain types particularly in the na-MCI type. CONCLUSION: Improving detection and control of cerebrovascular disease in aging individuals should be mandatory. Since the incidence of MCI and dementia will be expected to rise because of the progressive life expectancy, a better management of cerebrovascular disease could indeed prevent or delay the onset of MCI, or could delay progression of MCI to dementia.

A prospective, randomized study of empirical antifungal therapy for the treatment of chemotherapy-induced febrile neutropenia in children.

Given that the rationale for empirical antifungal therapy in neutropenic children is limited and based on adult patient data, we performed a prospective, randomized, controlled trial that evaluated 110 neutropenic children with persistent fever. Those at high risk for invasive fungal infections (IFI) received caspofungin (Arm C) or liposomal amphotericinB (Arm B); those with a lower risk were randomized to receive Arm B, C, or no antifungal treatment (Arm A). Complete response to empirical antifungal therapy was achieved in 90/104 patients (86·5%): 48/56 at high risk (85·7%) [88·0% in Arm B; 83·9% in Arm C (P = 0·72)], and 42/48 at low risk (87·5%) [87·5% in control Arm A, 80·0% Arm B, 94·1% Arm C; (P = 0·41)]. None of the variables tested by multiple logistic regression analysis showed a significant effect on the probability to achieve complete response. IFI was diagnosed in nine patients (8·2%, 95% confidence interval, 3·8-15·0). This randomized controlled study showed that empirical antifungal therapy was of no advantage in terms of survival without fever and IFI in patients aged <18 years and defined with low risk of IFI. Higher risk patients, including those with relapsed cancer, appear to be the target for empirical antifungal therapy during protracted febrile neutropenia.