Multichannel optical atomic magnetometer operating in unshielded environment

A multi-channel atomic magnetometer operating in an unshielded environment is described and characterised. The magnetometer is based on D1 optical pumping and D2 polarimetry of Cs vapour contained in gas-buffered cells. Several technical implementations are described and discussed in detail. The demonstrated sensitivity of the setup is 100fT/Hz^1/2 when operating in the difference mode.Comment: 9 pages, 5 figures, appearing in Appl.Phys.

A Non-Inductive Magnetic Eye-Tracker: From Dipole Tracking to Gaze Retrieval

We analyze the information that can be retrieved from the tracking parameters produced by an innovative wearable eye tracker. The latter is based on a permanent-magnet marked corneal lens and by an array of magnetoresistive detectors that measure the magnetostatic field in several positions in the eye proximity. We demonstrate that, despite missing information due to the axial symmetry of the measured field, physiological constraints or measurement conditions make possible to infer complete eye-pose data. Angular precision and accuracy achieved with the current prototypical device are also assessed and briefly discussed. The results show that the instrumentation considered is suitable as a new, moderately invasive medical diagnostics for the characterization of ocular movements and associated disorders

Fast, cheap, and scalable magnetic tracker with an array of magnetoresistors

We present the hardware of a cheap multi-sensor magnetometric setup where a relatively large set of magnetic field components is measured in several positions by calibrated magnetoresistive detectors. The setup is developed with the scope of mapping the (inhomogeneous) field generated by a known magnetic source, which is measured as superimposed to the (homogeneous) geomagnetic field. The final goal is to use the data produced by this hardware to reconstruct position and orientation of the magnetic source with respect to the sensor frame, simultaneously with the orientation of the frame with respect to the environmental field. Possible applications of the setup are shortly discussed, together with a synthetic description of the data elaboration and analysis.Comment: 10 pages, 7 figures, 30 ref

Validation of a fast and accurate magnetic tracker operating in the environmental field

We characterize the performance of a system based on a magnetoresistor array. This instrument is developed to map the magnetic field, and to track a dipolar magnetic source in the presence of a static homogeneous field. The position and orientation of the magnetic source with respect to the sensor frame is retrieved together with the orientation of the frame with respect to the environmental field. A nonlinear best-fit procedure is used, and its precision, time performance, and reliability are analyzed. This analysis is performed in view of the practical application for which the system is designed that is an eye-tracking diagnostics and rehabilitative tool for medical purposes, which require high speed ($\ge 100$~Sa/s) and sub-millimetric spatial resolution. A throughout investigation on the results makes it possible to list several observations, suggestions, and hints, which will be useful in the design of similar setups.Comment: 12 pages, 9 figs, 15 ref

A Wearable Wireless Magnetic Eye-Tracker, in-vitro and in-vivo tests

A wireless, wearable magnetic eye tracker is described and characterized. The proposed instrumentation enables simultaneous evaluation of eye and head angular displacements. Such a system can be used to determine the absolute gaze direction as well as to analyze spontaneous eye re-orientation in response to stimuli consisting in head rotations. The latter feature has implications to analyze the vestibulo-ocular reflex and constitutes an interesting opportunity to develop medical (oto-neurological) diagnostics. Details of data analysis are reported together with some results obtained in-vivo or with simple mechanical simulators that enable measurements under controlled conditions

Assessment Of Circulating Endothelial Cells And Their Progenitors As Potential Biomarkers Of Disease Activity And Damage Accrual In Behçet's Syndrome

PURPOSE: To explore the potential role of circulating endothelial cells (CECs) and their progenitors (EPCs) as biomarkers of disease activity and damage accrual in patients with Behçet's syndrome (BS), by using a standardised and reliable flow cytometry protocol. PATIENTS AND METHODS: CECs and EPCs were assessed in 32 BS patients and 11 gender/age/smoking habits matched healthy controls (HC). They were identified by flow cytometry as alive/nucleated/CD45-negative/CD34-bright/CD146-positive and alive/nucleated/CD45-negative/CD34-bright/CD309-positive events, respectively. In BS patients, demographic and clinical features, including disease activity (assessed by Behçet's disease current disease activity form, BDCAF) and irreversible damage accrual (by the vasculitis damage index, VDI) were recorded. Uni- and multivariate analysis were performed to compare the CECs and EPCs concentrations in BS vs HC and to identify potential associations with demographic or clinical features. RESULTS: The CECs concentration was significantly higher in the BS patients than HCs [median (IQR) 15.0 (7.5-23.0) vs 6.0 (2.0-13.0) CECs/mL, p=0.024]. In BS patients, no significant associations were found between CECs and demographic features, present and past clinical manifestations, BDCAF score and ongoing treatment. A significant association was observed between CECs and organ damage, as assessed by the VDI (rho 0.356, p=0.045). Higher levels of CECs were especially associated with vascular damage [median (IQR) 23.0 (14.0-47.0) vs 13.0 (6.0-19.0) CECs/mL, p=0.011], including arterial aneurysm and stenosis, complicated venous thrombosis, cerebrovascular accident. The concentration of EPCs did not significantly differ between the BS and HC [median 26.5 (13.0-46.0) vs 19.0 (4.0-42.0) EPCs/mL, p=0.316] and no significant associations were observed between their levels and any clinical characteristic. CONCLUSION: Our study suggests that the CECs concentration is significantly higher in BS than healthy subjects, and it mainly correlates with vascular damage. A longitudinal extension of the present study on a wider cohort would be useful to validate the potential role of CECs as a marker or, hopefully, predictor of vascular damage in BS

Total Skin Electron Therapy Stanford Technique Evolution With Monte Carlo Simulation Toward Personalized Treatments For Cutaneous Lymphoma

Current Total Skin Electron Therapy (TSET) Stanford technique for cutaneous lymphoma, established in the 70's, involves a unique irradiation setup, i.e. patient's position and beam arrangement, for all patients with ensuing great variability in dose distribution and difficult dose optimization. A Geant4-based simulation has been developed to explore the possibility of personalizing the dose to each patient's anatomy. To achieve this optimization of the treatment method, this project enrolls different aspects of the clinical and computational techniques: starting with the knowledge of the experimental parameters involving TSET practice, passing through an innovative approach to model the patient's anatomy, a precise description of the electron beam and a validated configuration of the physics models handling the interactions of the electrons and of secondary particles. The Geant4-based simulation models the patient as a tessellated solid derived from the optical scan of her/his body, realistically reproduces the irradiation environment in detail and calculates the energy deposition corresponding to each facet of the patient's scanned surface. The resulting three-dimensional dose distribution constitutes the basis for the personalization of the medical treatement as appropriate to each patient's specific characteristics.Comment: Presented at the 2022 IEEE Nuclear Science Symposiu

The 8 and 9 September 2002 flash flood event in France: a model intercomparison

Within the framework of the European Interreg IIIb Medocc program, the HYDROPTIMET project aims at the optimization of the hydrometeorological forecasting tools in the context of intense precipitation within complex topography. Therefore, some meteorological forecast models and hydrological models were tested on four Mediterranean flash-flood events. One of them occured in France where the South-eastern ridge of the French “Massif Central”, the Gard region, experienced a devastating flood on 8 and 9 September 2002. 24 people were killed during this event and the economic damage was estimated at 1.2 billion euros. To built the next generation of the hydrometeorological forecasting chain that will be able to capture such localized and fast events and the resulting discharges, the forecasted rain fields might be improved to be relevant for hydrological purposes. In such context, this paper presents the results of the evaluation methodology proposed by Yates et al. (2005) that highlights the relevant hydrological scales of a simulated rain field. Simulated rain fields of 7 meteorological model runs concerning with the French event are therefore evaluated for different accumulation times. The dynamics of these models are either based on non-hydrostatic or hydrostatic equation systems. Moreover, these models were run under different configurations (resolution, initial conditions). The classical score analysis and the areal evaluation of the simulated rain fields are then performed in order to put forward the main simulation characteristics that improve the quantitative precipitation forecast. The conclusions draw some recommendations on the value of the quantitative precipitation forecasts and way to use it for quantitative discharge forecasts within mountainous areas

Metagenomics and microscope revealed T. trichiura and other intestinal parasites in a cesspit of an Italian nineteenth century aristocratic palace

This study evidenced the presence of parasites in a cesspit of an aristocratic palace of nineteenth century in Sardinia (Italy) by the use of classical paleoparasitological techniques coupled with next-generation sequencing. Parasite eggs identified by microscopy included helminth genera pathogenic for humans and animals: the whipworm Trichuris sp., the roundworm Ascaris sp., the flatworm Dicrocoelium sp. and the fish tapeworm Diphyllobothrium sp. In addition, 18S rRNA metabarcoding and metagenomic sequencing analysis allowed the first description in Sardinia of aDNA of the human specific T. trichiura species and Ascaris genus. Their presence is important for understanding the health conditions, hygiene habits, agricultural practices and the diet of the local inhabitants in the period under study