Literatura académica sobre el tema "Vcadb"

A new CAD system, which is called Volume-CAD (VCAD) have been developed. We carried out research and development of VCAD fabrication process based on VCAD/CAM precision control. In this study, a developed V-CAM had been used for a polishing fundamental experiment of a free form surface. The relationship between NC resolution and form accuracy of polished surface are discussed.

Patients with mild chronic obstructive pulmonary disease (COPD) demonstrate resting pulmonary vascular dysfunction as well as a blunted pulmonary diffusing capacity (DLCO) and pulmonary capillary blood volume (VC) response to exercise. The transition from the upright to supine position increases central blood volume and perfusion pressure, which may overcome microvascular dysfunction in an otherwise intact alveolar-capillary interface. The present study examined whether the supine position normalized DLCO and VC responses to exercise in mild COPD. Sixteen mild COPD participants and 13 age-, gender-, and height-matched controls completed DLCO maneuvers at rest and during exercise in the upright and supine position. The multiple [Formula: see text]-DLCO method was used to determine DLCO, VC, and membrane diffusion capacity (DM). All three variables were adjusted for alveolar volume (DLCOAdj, VCAdj, and DMAdj). The supine position reduced alveolar volume similarly in both groups, but oxygen consumption and cardiac output were unaffected. DLCOAdj, DMAdj, and VCAdj were all lower in COPD. These same variables all increased with upright and supine exercise in both groups. DLCOAdj was unaffected by the supine position. VCAdj increased in the supine position similarly in both groups. DMAdj was reduced in the supine position in both groups. While the supine position increased exercise VCAdj in COPD, the increase was of similar magnitude to healthy controls; therefore, exercise VC remained blunted in COPD. The persistent reduction in exercise DLCO and VC when supine suggests that pulmonary vascular destruction is a contributing factor to the blunted DLCO and VC response to exercise in mild COPD. NEW & NOTEWORTHY Patients with mild chronic obstructive pulmonary disease demonstrate a combination of reversible pulmonary microvascular dysfunction and irreversible pulmonary microvascular destruction.

Objectives: Off pump TACR/MACR performed in experienced hands hascomparable results to on pump TACR/MACR. Period: January-2012 to December-2015.Material and method: 405 patients with two and three vessel coronary artery disease (two &three VCAD) underwent OPCAB at the department of cardiac surgery, Jinnah hospital, Lahore.73 of them got total or multiple arterial coronary revascularizations. 34 patients (41%) hadtwo VCAD and 47 (59%) had three VCAD. Total arterial revascularization was performed in 70(95.8%) patients using right internal mammary artery and left internal mammary artery and/orradial artery. 3 (4.10%) patients got multiple arterial grafts using BITA, RA and SVG. Results:There was no death reported in first 30 days post operatively. Deep sternal wound infectionoccurred in only one patient. The rate of perioperative stroke and renal failure was zero. Two(2.46%) patients had acute MI and 1 patient was reopened due to bleeding. Conclusion: Weconclude that early outcome of OPCAB total or multiple arterial coronary revascularizations, inexperienced hands, are as safe and effective as ONCAB.

Under investigation in this paper is a variable-coefficient AB (vcAB) system, which describes marginally unstable baroclinic wave packets in geophysical fluids and ultra-short pulses in nonlinear optics. The modulation instability analysis of solutions with variable coefficients in the presence of a small perturbation is studied. The modified Darboux transformation (mDT) of the vcAB system is constructed via a gauge transformation. The first-order non-autonomous rogue wave solutions of the vcAB system are presented based on the mDT. It is found that the wave amplitude of [Formula: see text] exhibits two types of structures, i.e. the double-peak structure appears if the plane-wave solution parameter [Formula: see text] is equal to zero, while selecting [Formula: see text] yields a single-peak one. Effects of the variable coefficients on the rogue waves are graphically discussed in detail. The periodic rogue wave and composite rogue wave are obtained with different inhomogeneous parameters. Additionally, the nonlinear tunneling of the rogue waves through a conventional hyperbolic nonlinear well and barrier are investigated.

The Volume-CAD System Research Program aims at developing a core technology for data integration of computerized design, analysis, manufacturing, and testing processes. The potential applications of the Volume-CAD environment cover a large area of engineering and biomedical design. In this paper, we shall mainly focus on the VCAD-based software for the structural analysis and the simulation of casting processes.

Lo scopo del nostro studio è stato quello di dimostrare e confermare l’utilità dell’ampio spettro di metodiche fornite dalla tecnologia ecografica tridimensionale e quadridimensionale, nel diagnosticare, monitorare, prevedere o studiare determinate patologie ostetriche. Il nostro studio ha coinvolto patologie perinatali che risultano essere ancora di problematica gestione. In particolare si è cercato di approfondire la diagnosi e la previsione delle patologie cromosomiche, della pre-eclampsia e della pre-eclampsia grave tale da richiedere l’espletamento del parto prima di 32 settimane di gestazione, di alcune malformazioni cardiache quali la Trasposizione completa e corretta dei Grossi Vasi, lo studio della funzionalità cardiaca in feti normali e con ritardo di crescita intrauterino. Per tutti gli esami effettuati è stato utilizzato un ecografo Voluson 730 (G. E. Healthcare). La tecnica ultrasonografica utilizzata è stata quella tradizionale bidimensionale con la misurazione di distanze (valvole cardiache, biometria fetale), con l’uso del Doppler colore e pulsato (visualizzazione di vasi sanguigni quali le arterie uterine e l’arteria ombelicale, dei flussi sanguigni intracardiaci, la visualizzazione dei diagrammi di flusso dei vasi uterini, la misurazione del PI, TVI, dei flussi trans-valvolari cardiaci). La tecnica tradizionale è stata integrata e confrontata con quella tridimensionale e quadridimensionale. Gli apparecchi ecografici tridimensionali acquisiscono un singolo volume di voxels mediante una “spazzolata” del fascio ultrasonoro attraverso l’area di interesse, e ciò permette l’approccio standard per lo studio tridimensionale delle strutture non-cardiovascolari. L’immagine così ottenuta è un’immagine statica. La tecnologia 4D aggiunge l’elemento movimento ed in particolare lo Spatio-Temporal Image Correlation (STIC) permette di ottenere una sequenza di un singolo ciclo cardiaco, come fosse un esame bidimensionale condotto dal vivo ed in tempo reale. La sovrapposizione del colore è invece particolarmente utile per verificare la normale emodinamica cardiaca o la presenza di eventuali anomalie. L’utilizzo del power Doppler tridimensionale ha permesso di studiare gli indici di vascolarizzazione placentare quali vascularization index (VI), flow index (FI) e vascularization flow index (VFI). Per studiare il volume di un tessuto, di un organo o di una cavità (nel caso specifico dell’intera placenta o delle cavità cardiache) è stata utilizzata la tecnica VOCAL (Virtual Organ Computer-Aided anaLysis), che permette di ottenere una sequenza di diverse sezioni dopo una rotazione di alcuni gradi rispetto alla precedente. In ogni piano il contorno è stato tracciato manualmente. Il computer ha poi eseguito la ricostruzione e calcolato il volume. Per studiare le scansioni utili a diagnosticare malformazioni cardiache quali la Trasposizione dei grossi vasi è stata utilizzata la metodica SonoVCAD (Sonographically based Volume Computer-AideD) che ricostruisce automaticamente le scansioni cardiache diagnostiche da un volume quadridimensionale del torace fetale ottenuto tramite STIC. Le tecniche descritte sono state utilizzate nella ricerca clinica, permettendo la stesura dei quattro studi analizzati di seguito.
The aim of this study was to demonstrate and confirm the utility of the wide spectrum of methods provided by the 3D and 4D ultrasound technology, in increasing the detection rate, monitoring, predicting and studying several obstetrical pathologies. Our study involved perinatal pathologies where management could be difficult. In particular we tried to go into diagnosis and prediction of chromosomal abnormalities, pre-eclampsia and severe pre-eclampsia requiring delivery prior to 32 weeks of gestation, some cardiac defect like complete and correct trasposition of the great arteries and the study of cardiac function in normal and growth restricted fetuses. Every scan was performed using a Voluson 730 ultrasound machine.(G. E. Healthcare). We used the traditional bidimensional ultrasound technology to measure distances (cardiac valves, fetal biometry), with color and pulsed Doppler use (blood vessels visualization like uterin arteries and umbilical artery, intracardiac blood flow, uterin arteries waveform visualization, measure of PI, TVI and cardiac trasvalvular flows). T raditional technique was integrated and comparated to the tridimensional and quadridimensional ones. Ultrasound 3D machines acquire a single volume of voxels by a sweep of ultrasound troughout the interest area, and this allows the 3D approach for the study of non-vascular structures. This provides a static image. The 4D technology adds movement and in particular the STIC software (Spatio-Temporal Image Correlation) allows to obtain a sequence of a single cardiac cicle, like a bidimensional examination in real time. Adding color is useful to verify the cardiac flows and the presence ofe several abnormalities. 4D Power Doppler use allowed study of placental vascularization indices like vascularization index (VI), flow index (FI) e vascularization flow index (VFI). The VOCAL software was used to study the volume of a tissue, organ or cavity (for exemple the whole placenta or cardiac cavities) producing a sequence of several sections of the heart, each obtained after a rotation from the previous one. In each plane the contour was traced manually, and at the end, the computer provided the reconstruction of the ventricle and calculated its volume. To detect cardiac malformations such Trasposition of the great arteries we used the SonoVCAD software (Sonographically based Volume Computer-Aided anaLysis) that automatically retrieves diagnostic cardiac planes from a 4-dimensional volume of the fetal chest obtained with spatiotemporal image correlation (STIC). We finnally concluded that the 3D/4D technique provides several benefits, because the study of the volumes is possible offline, after sacnning and can be repeated by different operators or several times by the same operator, giving the possibility of double-blinded studies. The automatic approach shows good retrieval of diagnostic cardiac planes in fetuses with TGA, which may improve diagnostic efficacy for this disease. There is a good agreement between SV measured either by 2D Doppler or by 4D STIC. The 4D STIC represents a simple and rapid technique to estimate fetal SV and promises to become the method of choice. The combination of abnormal uterine artery Doppler and low placental volume at 11–14 weeks achieves better results than does either test alone in the prediction of pre-eclampsia. We provide normal ranges of placental vascular indices between 11 + 0 and 13 + 6 weeks of gestation, which may be useful in future research on placental vascularity in certain at-risk pregnancies. Additional studies are needed to further validate these methods and it’s very important to remember that to obtain a quality volume we need to have a good bidimensional image.