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We propose a procedure to implement Dirichlet velocity boundary conditions for complex shapes that use data from a single node only, in the context of the lattice Boltzmann method. Two ideas are at the base of this approach. The first is to generalize the geometrical description of boundary conditions combining bounce-back rule with interpolations. The second is to enhance them by limiting the interpolation extension to the proximity of the boundary. Despite its local nature, the resulting method exhibits second-order convergence for the velocity field and shows similar or better accuracy than the well-established Bouzidi's scheme for curved walls [M. Bouzidi, M. Firdaouss, and P. Lallemand, Phys. Fluids 13, 3452 (2001)]PHFLE61070-663110.1063/1.1399290. Among the infinite number of possibilities, we identify several meaningful variants of the method, discerned by their approximation of the second-order nonequilibrium terms and their interpolation coefficients. For each one, we provide two parametrized versions that produce viscosity independent accuracy at steady state. The method proves to be suitable to simulate moving rigid objects or surfaces moving following either the rigid body dynamics or a prescribed kinematic. Also, it applies uniformly and without modifications in the whole domain for any shape, including corners, narrow gaps, or any other singular geometry.

Background: the aim of this study was to perform an Italian telematics survey analysis on the changes in couples’ sex lives during the coronavirus disease 2019 (COVID-19) lockdown. Methods: a multicenter cross sectional study was conducted on people sexually active and in stable relationships for at least 6 months. To evaluate male and female sexual dysfunctions, we used the international index of erectile function (IIEF-15) and the female sexual function index (FSFI), respectively, marital quality and stability were evaluated by the marital adjustment test (items 10–15), to evaluate the severity of anxiety symptoms, we used the Hamilton Anxiety Rating Scale. The effects of the quarantine on couples’ relationships was assessed with questions created in-house. Results: we included 2149 participants. The sex lives improved for 49% of participants, particularly those in cohabitation, for 29% it deteriorated, while for 22% of participants it did not change. Women who responded that their sex lives deteriorated had no sexual dysfunction, but they had anxiety, tension, fear, and insomnia. Contrarily, men who reported deteriorating sex lives had erectile dysfunctions and orgasmic disorders. In both genders, being unemployed or smart working, or having sons were risk factors for worsening the couples’ sex lives. Conclusion: this study should encourage evaluation of the long-term effects of COVID-19 on the sex lives of couples.

PURPOSE: to evaluate clinical predictors of positive surgical margins (PSMs) in a large multicenter prospective observational study and to develop a clinic nomogram to predict the likelihood of PSMs after partial nephrectomy (PN). MATERIALS AND METHODS: We prospectively evaluated 4308 patients who had surgical treatment for renal tumors between January 2013 and December 2016 at 26 urological Italian Centers (RECORd 2 project). Two multivariable logistic models were evaluated to predict the likelihood of PSMs. Center caseload was dichotomized using a visual assessment adjusted for several predictors of PSMs. A nomogram predicting PSMs was developed. RESULTS: Overall, 2076 patients treated with PN were evaluated. pT1a, pT1b, pT2 and pT3a were recorded in 68.7%, 22.6%, 2.1% and 6.6% of the patients, respectively. PSMs were recorded in 342 (16.5%) patients. From a null multivariable model against number of PN/year, 60 PN/year were identified as the best cut-off to define a high-volume centre. At multivariable analysis, clinical stage (cT1a vs. cT2 [OR 1.94]; p = 0.03), volume centre (≤60 PN/year) (OR 2.22; p

We present a lattice Boltzmann model designed for the simulation of dilute and dense finite-sized rigid particle suspensions under applied shear. We use a bottom-up approach and fully resolve the mechanical interaction between fluid and particles. Our model consists in coupling a lattice Boltzmann scheme for Newtonian and incompressible fluid flows with an immersed boundary scheme to simulate two-ways fluid-particles interaction. We introduce a simple yet robust contact model that includes repulsive elastic collision between particles, and neglects lubrication corrections. We apply this model to simple sheared flow with rigid spherical particles and we provide results for the relative apparent viscosity of the particle suspension as a function of the particle volume fraction and strain rate of the flow. We show that, using the proposed approach, there is no need for a lubrication model in the Newtonian regime, provided that an elastic contact model is included. Our algorithm, therefore, can be based only on physically sound and simple rules, a feature that we think to be fundamental for aiming at resolving polydispersed and arbitrarily shaped particle suspensions. Comparing our results with Krieger–Dougherty semi-empirical law, we confirm that the simulations are not sensitive to the particle Reynolds number for Rep ≪ 1 in the Newtonian regime. We show that the proposed model is sufficient to obtain a correct description of the rheology of particle suspension up to volume fraction equal to 0.55 (approaching the critical random packing fraction for monodispersed spheres), which goes beyond the state of the art.

We sought to test the content validity of a new training model for flexible ureteroscopy: the Key-Box.Sixteen medical students were randomized to undergo a 10-day training consisting of performing 10 different exercises aimed at learning specific movements with the flexible ureteroscope, and how to catch and release stones with a nitinol basket using the Key-Box (n = 8 students in the training group, n = 8 students in the nontraining control group). Subsequently, an expert endourologist (O.T.) blindly assessed skills acquired by the whole cohort of students through two exercises on ureteroscope manipulation and one exercise on stone capture selected among those used for the training. A performance scale (1-5) assessing different steps of the procedure was used to evaluate each student. Time to complete the exercises was measured. Mann-Whitney Rank Sum test was used for comparisons between the two groups.Mean scores obtained by trained students were significantly higher compared with those obtained by nontrained students (all p 0.001). All trained students were able to complete the two exercises on ureteroscope manipulation within 3 minutes, whereas two students (25%) were not able to finish the exercise on stone capture. Conversely, four (50%) and six (75%) nontrained students were not able to finish one out of the two exercises on ureteroscope manipulation and the exercise on stone capture, respectively. The mean time to complete the three exercises was 76.3, 69.9, and 107 and 172.5, 137.9, and 168 seconds in the trained and nontrained groups, respectively (all p 0.001).The K-Box

Introduction Primary female bladder neck obstruction is a rare clinical condition characterized by the absence/incomplete bladder neck opening during the voiding phase of micturition. Methods We present the cases of two women complaining dysuria, abdominal straining and sensation of incomplete bladder emptying. Videourodynamic evaluation was fundamental for a correct diagnosis. Results Videourodynamic evaluation showed a high detrusor pressure during emptying phase, partial use of abdominal strain, very low urine flow rate and significant postvoid residual; imaging showed a defect in the physiological funneling of the bladder neck, absent or incomplete. The first step therapy is represented by oral alpha-blockers and clean intermittent self-catheterization in case of high postvoid residual. Surgical operations, such as bladder neck incision and resection, represent the last option. Conclusions In our experience, bladder neck obstruction is a rare condition in women and only a complete clinical evaluation associated with videourodynamic study can lead to an appropriate diagnosis and treatment.

Pelvic floor damage is a well-recognized consequence after childbirth, and a huge number of studies give interesting data regarding its epidemiology. A recent study of Glazener et al. collected data from 3,763 women 12 years after childbirth and found an objective prolapse in 24 % of women; they reported that a body mass index (BMI) over 25 and age over 25 years at first delivery were associated with worse prolapse symptom score (POP-SS), and that in women over 30 years at their first pregnancy there was a significant association with the onset of prolapse [1]. Analyses about risks factors related with prolapse surgery have been made: Women older than 30 years at first vaginal delivery had an incidence of POP surgery of 13.8 %, while in younger women it was only 6.8 % [2]. Prolapse stage usually changes after delivery: Elenskaia et al. reported that 5 years after childbirth the stage of prolapse worsen after vaginal delivery but not after cesarean [3]. Other older studies reported that 50 % of parous women have some degrees of genital prolapse, with 10–20 % symptomatic [4]. Anyway a precise epidemiology about POP is not easily available, due to lack of a standard evaluation. Samuelsson et al. reported that about 44 % of parous women have some form of POP [5]. It is to notice that clinical prolapse evaluation is different from subjective prolapse perception with symptoms: In a study by Durnea et al. with 202 participants despite the high prevalence of POP on POP-Q examination, only 20 % of participants were symptomatic [6].

Over the last two decades there has been an increase in the incidence of kidney stone disease with a simultaneous rise in the use of ureteroscopy for its management [1]. Flexible ureteroscopy training is variable and still largely dependent on high fidelity models and virtual reality (VR) simulation, both of which are expensive and not readily available in many parts of the world. There is also a lack of good quality bench trainers. In a recent survey of endourologists worldwide, flexible ureteroscopy was considered as a first line treatment for stones

Flexible ureterorenoscopy (F-URS) plays a major role in the management of kidney stones. Ureteral access sheaths (UAS) are important tools for F-URS. In this study, we aimed to evaluate the difference in intrarenal pressures between different flexible ureteroscopes while using the same UAS and to calculate the irrigation flow variance.Eight different flexible ureteroscopes were tested with five different UAS on an artificial kidney model to measure intrarenal pressures and irrigation flow. Irrigation at 60 cmH2O pressure was performed; the pressure and the irrigation flow amount were recorded with different states of the operator channel: Free, with the laser fiber (272 μm), and with the nitinol basket (1.9F) inside.The highest pressure recorded was 46.68 cmH2O with Wolf Boa and 9.5/11.5F Cook Medical UAS. All the ureteroscopes that fit inside the 10/12F Coloplast ReTrace provided pressures below 40 cmH2O. The inner diameter of the 10/12F Rocamed Bi-Flex is actually 11F, so intrarenal pressures were lower and irrigation flow was higher. With the 11/13F Boston Scientific Navigator HD and 12/14F Coloplast ReTrace, the pressures were very low. The irrigation flow measurements were in concordance with pressure measurements.The ureteroscope sizes diminished with advancements in technology. Small-sized ureteroscopes can provide low intrarenal pressures with good irrigation flow when used with convenient small-sized access sheaths. The compatibility between the ureteroscopes and UASs should be anticipated by all endourologists and considered during F-URS. The advantages of 10/12 UASs in terms of intrarenal pressure and irrigational flow should make these access sheaths an interesting first-line choice.

that UI and UTI phenotypes have negative bidirectional impact on each other, which worsens with aging. METHODS: UTI was induced by inoculations of z108 uropathogenic E coli (UPEC89) in 0.05ml PBS into the bladder via a transurethral catheter. Control mock infected mice received 0.05 ml saline. We tested various components of our hypotheses by 4 sets of experiments: i) Determined the impact of recurrent UTI on UI by measuring leak point pressure (LPP) in 20wk old B6 mice 2wk after 2 infections (1day apart) with UPEC89 (UTIx2 n1⁄410, Saline n1⁄46). ii) Determined the impact of UI on urine bacterial clearance in 20wk old B6 mice after UPEC89 challenge. UI was created by pudendal nerve transection in 17wk old mice, followed by single UTI induction 3wk later (PNTþUTIx1 n1⁄410). Bacterial counted for urine collected on day 1,2,3,5,9, and 14. Control groups included: Saline n1⁄46, UTIx1 n1⁄410, PNTþSaline n1⁄46; iii) Determined if recurrent UTI in >80wk old B6 mice worsens UI 2wk following infection (UTIx2 aged mice: n1⁄415, Saline control aged mice: n1⁄410) compared to experiment (i) 20wk old mice. iv) Determined if bacterial clearance following 2 challenges with UPEC89 was diminished in >80wk old mice compared to 20wk old mice during 2wk. RESULTS: i) No significant differences between LPP of infected andcontrolmice 2wk after inoculation. ii) Control, andPNTgroup remained sterile during the study. All UTIx1 induced mice, and 86% of PNTþUTIx1 mice developedUTI by day 2. Complete urine bacterial clearance rate was z40% lower in PNTþUTIx1 mice compared to UTIx1 alone. No LPP differencewas found inPNTþUTI, saline,UTI, andPNT treatedgroupsat day 14. iii) Significantly reduced LPP was observed in aged mice with UTIx2 compared to saline controls (P 80wkoldmicewasnotobservedbyday14,while 40%of20wkoldmiceurineclearedbyday14. *Homogenizedkidney tissue had negative microbial culture in all animals. CONCLUSIONS: Recurrent UTI failed to induce UI in 20wk old B6 mice but was associated with increased UI in >80wk old mice. Additionally >80wk old mice cleared UTI infections slower than 20wk old mice. Our finding suggests aging prolongs bacterial clearance while prolonged bacterial infection promotes the development of UI.

When we refer to the term “male urinary incontinence” we implicitly refer to several anatomical structures involved in these complex mechanisms. A relevant part of these structures plays a pivotal role when radical prostatectomy is performed. In this chapter all the structures involved with urinary continence will be analyzed, both from an anatomical and functional point of view. The urinary sphincter and the bladder neck, the puboprostatic ligamentous complex, the rectourethralis muscle, the prostate vascular supply, the laevator ani muscle, the inferior hypogastric plexus (IHP), the Denonvillieres’ fascia, and the obturatory fossa will be discussed in order. Most of the anatomical descriptions will be accompanied with a brief embryological contextualization, according to the authors’ conviction that anatomical knowledge should be always contextualized with an embryological setting.

Objectifs Tester l’interet d’un nouvel outil d’entrainement a l’ureteroscopie souple (URSS). Methodes La K-Box® est un modele reproduisant plusieurs configurations d’arbre urinaire ( Fig. 1 , Fig. 2 ). Seize etudiants en medecine sans experience en URSS ont ete repartis en deux groupes de huit de maniere randomisee et invites a tester ce dispositif. Un groupe avait le droit de s’entrainer quotidiennement a dix exercices specifiques pendant dix jours alors que l’autre non. A la fin de cette periode d’essai, tous les etudiants etaient evalues sur la manipulation de l’URSS par une echelle de performance specifique et sur le temps mis pour realiser des exercices specifiques aux boites de la K-Box® ( Tableau 1 ). La notation selon l’echelle a ete realisee par un urologue confirme en insu. Resultats Les scores moyens obtenus selon l’echelle dediee pour etudier la manipulation etaient tous statistiquement meilleurs chez les etudiants entraines pendant la periode de dix jours compares a ceux n’ayant pas eu d’entrainement, p Tableau 2 ). Conclusion La K-Box apparait etre un nouvel outil d’entrainement efficace pour l’initiation a l’URSS.