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Endoscopic treatment of vesicoureteral reflux (VUR) is an important minimally invasive surgical approach in patients undergoing surgical treatment of VUR. In our past experience, we observed that a bulking agent mound sagittal diameter of 10 mm is the main predictor of effectiveness of the procedure. Moreover we noticed that the use of intraoperative ultrasound, allows the surgeon to better identify the site, volume and shape of the bulking agent injected, finally reducing operative time. We aimed to evaluate if the intraoperative ultrasound assistance could definitively improve effectiveness of the endoscopic procedure. We retrospectively compared two series treated with endoscopic procedures for intermediate and high grade primary VUR, respectively without (series A) and with (series B) intraoperative ultrasound (IO-US). In all patients VCUG was performed to assess VUR grade and to verify resolution or VUR downgrading during the follow-up. A total of 177 ureteric units were treated. Endoscopic procedures globally were effective in 68/96 ureters (70.8 %) in series A and in 68/81 ureters (83.9 %) in series B. No significant differences in effectiveness were observed comparing the series with regard to VUR grades, but a significant difference is shown (p < 0.05) when grouping grades III-V VUR. No significance in differences of volume injected were detected, but operative time was significantly lower in series B (27.5 min vs 19.6 min, p < 0.05). Mean sagittal mound diameter measured during cystoscopy in series B was 10.45 mm (range 8.5–14.2 mm). The intraoperative ultrasound assistance during endoscopic treatment of VUR could represent a valid tool for surgeons to better identify location, volume and shape of the bulking agent. Furthermore, the use of an objective parameter of evaluation of the implant can overcome the subjective intraoperative evaluation of the implant itself, improving results for experienced surgeons and reducing the learning-curve for inexperienced ones. Results of endoscopic injection of bulking-agent can be improved with intraoperative ultrasound, allowing at the same time a significant reduction of operative time. [ABSTRACT FROM AUTHOR]

Abstract: A geometrical approach to design centering of analog circuits is presented. This approach exploits symbolic analysis techniques, which permit one to perform only a single simulation of the circuit to determine a set of parameter values maximizing the manufacturing yield. For linear, or linearized, circuits, with constraints on the frequency response, this approach can be an advantageous alternative to existing techniques of design centering, whose major limiting factor is the considerable computational effort required for multiple simulations of the circuit under consideration. After a brief description of the program implementing the proposed design centering approach, benchmark circuit examples previously published by other researchers are reported in order to compare the results obtained through the developed procedure with those of existing techniques. An example of a circuit with relatively large dimensions is also included. [Copyright &y& Elsevier]

In the present paper we analyse type III and type IV shock–shock interactions. The main emphasis of the paper is first to review the various shock–shock interference patterns that may occur, and the theoretical approaches: (1) to determine and to characterize the conditions for the transition from one type to another; and (2) to estimate the aerothermal loads for the most critical interactions. The paper then presents an experimental investigation focused on type III and type IV interferences, the goal being the assessment of the influence of the impinging shock strength. The results indicate that the most critical conditions occur when the supersonic jet (typical of type IV interaction) is nearly perpendicular to the body surface. The jet is found to exhibit a change from perpendicular to curved in the case of strong shock wave strength. The analysis also shows that shock/shock interactions may experience a hysteresis phenomenon which is typical of steady shock wave reflections. [Copyright &y& Elsevier]

• Direct numerical simulation of supersonic square duct flow is performed, up to Re τ = 500. • Classical compressibility transformations for velocity, developed for plane channel flow and boundary layer, are extended to the case of multiple walls. • The accuracy of temperature-velocity relations for square duct flow is studied. • The transport of a passive scalar field is also considered and the differences with respect to the temperature field are analyzed. We carry out direct numerical simulation of compressible square duct flow in the range of bulk Mach numbers M b = 0.2 − 3 , and up to friction Reynolds number Re τ = 500. The effects of flow compressibility on the secondary motions are found to be negligible, with the typical Mach number associated with the cross-stream flow always less than 0.1. As in the incompressible case, we find that the wall law for the mean streamwise velocity applies with good approximation with respect to the nearest wall, upon suitable compressibility transformation. The same conclusion also applies to a passive scalar field, whereas the mean temperature does not exhibit inertial layers because of nonuniformity of the aerodynamic heating. We further find that the same temperature/velocity relation that holds for planar channels is applicable with good approximation for square ducts, and develop a similar relation between temperature and passive scalars. [ABSTRACT FROM AUTHOR]

A general parametric representation function (Shape Function) for wind turbine – dedicated airfoils based on Taylor high-order polynomial series is presented for the first time. The design space and shape control function of the airfoil have been studied. The objective of the high-performance WT (Wind Turbine) airfoils was to maximise the lift/drag ratio at the design angle of attack both in free and fixed transitions. The optimised mathematical model of the airfoils is built combing genetic algorithm and the flow solver RFOIL. The new airfoil family (ranging in thickness from 15 to 20%) with target characteristics were designed for variable-speed operation with pitch control of large megawatt-sized rotors. Wind tunnel experiments for the WT180 airfoil were carried out for both clean and rough conditions. The experimental results for the lift and drag coefficients agree well with the RFOIL predictions. The testing verified the high lift/drag ratio and the high maximum lift coefficient for the WT180 airfoil. The results indicate that this novel design method is feasible to optimise wind turbine airfoils. [ABSTRACT FROM AUTHOR]

Abstract: The effect of carotid artery stenting (CAS) on cognitive function is still debated. Cerebral microembolism, detectable by post-procedural diffusion-weighted imaging (DWI) lesions, has been suggested to predispose to cognitive decline. Our study aimed at evaluating the effect of CAS on cognitive profile focusing on the potential role of cerebral microembolic lesions, taking into consideration the impact of factors potentially influencing cognitive status (demographic features, vascular risk profile, neuropsychological evaluation at baseline and magnetic resonance (MR) markers of brain structural damage). Thirty-seven patients with severe carotid artery stenosis were enrolled. Neurological assessment, neuropsychological evaluation and brain MR were performed the day before CAS (E0). Brain MR with DWI was repeated the day after CAS (E1), while neuropsychological evaluation was done after a 14-month median period (E2). Volumes of both white matter hyperintensities and whole brain were estimated at E0 on axial MR FLAIR and T1w-SE sequences, respectively. Unadjusted ANOVA analysis showed a significant CAS∗DWI interaction for MMSE (F=7.154(32), p=.012). After adjusting for factors potentially influencing cognitive status CAS∗DWI interaction was confirmed for MMSE (F=7.092(13), p=.020). Patients with DWI lesions showed a mean E2–E0 MMSE reduction of −3.1, while group without DWI lesions showed a mean E2–E0 MMSE of +1.1. Our study showed that peri-procedural brain microembolic load impacts negatively on cognitive functions, independently from the influence of patients-related variables. [Copyright &y& Elsevier]

Abstract: The aim of this article is to find a correlation between height and femur/skull measurements through Computed Tomography (CT) scans and derive regression equations for total skeletal height estimation in the Caucasian population. We selected 200 Caucasian patients from March 2010 to July 2011 who had to perform a CT scan for cancer restaging. The mean age is 64.5 years. Both sexes are represented by the same number of persons. Patients have executed a total body CT scan with contrast; once scan accomplished, we measured height through a digital scales. We analyzed CT scans of each patient, obtaining multiplanar reconstruction in sagittal and coronal planes with 1mm of thickness, and we measured 10 diameters of skull and femur. Then we performed a single and a multiple regression analysis considering the three diameters that better correlated with height. The skeletal diameters with the highest correlation coefficients with stature were femur lengths, length of cranial base (Ba-N), and distance from the posterior extremity of the cranial base to the inferior point of the nasal bone (Ba-NB). Although both femur and skull are skeletal segments used for stature estimation, in our sample femur gave stronger correlation with height than skull. h =35.7+1.48·BaN+2.32·BaNB+2.53·FEM and h =3.06·FEM+72.6 are the formulae that provided the most accurate stature assessment using multiple and single regression analysis respectively. [Copyright &y& Elsevier]