Quantum computing teaching with CoSpaces

The first prototypes of quantum computers sparked interest in quantum computing and the basic principles of quantum mechanics. The education project on the physical bases of quantum computing is part of this context, based on the experimental description with virtual methods of the physical implementation of Di Vincenzo's first 5 principles. The computation process is implemented as transformations of qubits encoded in the polarization of optical photons. These transformations are implemented as quantum gates made as 3D virtual objects using Blender. In detail, the models of: Laser Ar +, PBS, HWP / QWP, BBO, APD, SMF, Control electronics are made. With the 3D models, a virtual laboratory has been created within CoSpaces where it is possible to become familiar with the basic processes of quantum computing: production of announced photons, transformation of a qubit, measurement of a qubit, production of entangled photons, transformation of two qubits, measure of two qubits. The realization of physical models to be used in the metaverse could fill the didactic void due to the absence of quantum optics laboratories

Venous compliance and clinical implications

Compliance is a characteristic of every deformable system. Compliance is very clear concept in physics and mechanics but in clinics, perhaps, is not the same. However, in veins compliance fits perfectly with the function of drainage of the venous system. Volumetric increase (dV) of the content is correlated with pressure increase (dP) inside the vein according to the equation C'= dV/dP. In humans 75% of the blood is located in the venous system, primarily because the molecular components of a vein media layer is significantly more compliant to that of arteries. This property is fundamental to understanding the change in blood volume in response to a change in posture. Measurements of venous compliance in clinical practice can be done by the means of ultrasound, as well as with the plethysmography. Ultrasound methods assimilate the cross sectional area to the volume of the vein, because it reflects the blood content. Changes in cross sectional area can be reliably measured in response to a change in posture, while pressure can be derived from the hydrostatic pressure changes. Venous compliance is of paramount importance also in pulsatile veins such as the inferior or superior vena cava and the jugular veins, where high resolution ultrasound may accurately derive the cross sectional area. Clinical implications of the mechanical properties of the venous wall are extensively discussed, including the need of dedicated venous stenting, which takes into account venous compliance as the main parameter of the venous function. In addition, venous compliance is the interpretative key for a better understanding of plethysmography curves, as well as of varicose veins and of their return to normal cross sectional area following ambulatory venous pressure reduction

Conventional echo color Doppler versus ULA-OP in the assessment of venous flow model

The quantification of venous flows can be obtained by multiplying cross sectional area, measured on a B-mode video-clip, by velocity values, obtained with Doppler measurements. The Doppler angle between ultrasound (US) line and blood flow requires a manual adjustment. Establishing this parameter is critical in order to calculate blood velocity. However, the operator dependency gives high variable results. It is worth noting that a new class of vector Doppler devices can enhance the accuracy and precision of measurements. Such technology uses a double US line that leads to automatically know the Doppler angle. By comparing in an in vitro model of venous flow conventional echo color Doppler (ECD) equipment with the new device, we found a better minimal difference between the latter and the nominal flow rate (20%). On the contrary, the comparison with conventional ECD showed a difference ranging between 2% and 43%, according to the possible settings of the equipment. Our study demonstrates a better accuracy of the experimental device with respect to conventional ECD in measuring the venous flow rate

On the consistency of flow rate color Doppler assessment for the internal jugular vein

Color Doppler methodology to assess the vessel blood flow rate is based on the time averaged velocity of the blood measured in the longitudinal plane and the cross sectional area measurement taken either in the longitudinal plane, by assuming circular cross sectional area, or in the transversal plane. The measurement option in longitudinal plane is based on the assumption of circular cross sectional area, while the transversal one needs to evaluate both time-averaged velocity and cross sectional area in the same vessel point. A precise and validated assessment methodology is still lacking. Four healthy volunteers underwent internal jugular vein colour Doppler scanning. The cross sectional area was assessed by means of B-mode imaging in the transversal plane all along the vessel cervical course. During this assessment, cross sectional area, major and minor axis of the vessel were measured and recorded. The distance between the internal jugular vein wall and the skin surface were measured together with the intra-luminal diameter and statistically correlated with the cross sectional area data. The internal jugular vein cross sectional area measured on the transversal plane were significantly different from the cross sectional area calculated using the assumption of circular shape. The intra-luminal distance showed high correlation with the measured cross sectional area. The proper anatomical point in the cross sectional area transversal measurement can be identified by using the internal jugular vein intra-luminal distance as landmark

Patient-specific dosimetry in 90Y-lipiodol brachytherapy

Dottorato di ricerca in tecniche radioisotopiche. 12. ciclo. A.a. 1998-99. Relatore A. DelguerraConsiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7, Rome; Biblioteca Nazionale Centrale - P.za Cavalleggeri, 1, Florence / CNR - Consiglio Nazionale delle RichercheSIGLEITItal

Misurazione ecodoppler dell'outflow venoso cerebrale. Nuovi indici per diagnosi CCSVI.

Misurazione ecodoppler dell'outflow venoso cerebrale. Nuovi indici per diagnosi CCSV