One Net Fits All: A unifying semantics of Dynamic Fault Trees using GSPNs

Dynamic Fault Trees (DFTs) are a prominent model in reliability engineering. They are strictly more expressive than static fault trees, but this comes at a price: their interpretation is non-trivial and leaves quite some freedom. This paper presents a GSPN semantics for DFTs. This semantics is rather simple and compositional. The key feature is that this GSPN semantics unifies all existing DFT semantics from the literature. All semantic variants can be obtained by choosing appropriate priorities and treatment of non-determinism.Comment: Accepted at Petri Nets 201

New Ultra-minimally Invasive Surgical Treatment for Benign Prostatic Hyperplasia: A Systematic Review and Analysis of Comparative Outcomes

Context: Benign prostatic hyperplasia (BPH) associated with lower urinary tract symptoms (LUTS) is diagnosed in up to 80% of men during their lifetime. Several novel ultra-minimally invasive surgical treatments (uMISTs) for BPH/benign prostatic obstruction (BPO) have become available over the past 5 yr. Objective: To evaluate the perioperative and functional outcomes of recently introduced uMISTs for BPH/BPO, including Urolift, Rezūm, temporary implantable nitinol device, prostatic artery embolization (PAE), and intraprostatic injection. Evidence acquisition: A systematic literature search was conducted in December 2020 using Medline (via PubMed), Embase (via Ovid), Scopus, and Web of Science (registered on PROSPERO as CRD42021225014). The search strategy used PICO criteria and article selection was conducted in accordance with the PRISMA guidelines. The risk of bias and the quality of the articles included were assessed. A dedicated data extraction form was used to collect the data of interest. Pooled and cumulative analyses were performed to compare perioperative and functional outcomes between study groups. A random-effects model using the DerSimonian and Laird method was used to evaluate heterogeneity. Stata version 15.0 software was used for all statistical analyses. Evidence synthesis: The initial electronic search identified 3978 papers, of which 48 ultimately met the inclusion criteria and were included in the analysis. Pooled analysis revealed a uMIST benefit in terms of International Prostate Symptom Score (IPSS; −9.81 points, 95% confidence interval [CI] −11.37 to −8.25 at 1 mo; −13.13 points, 95% CI −14.98 to −11.64 at 12 mo), maximum flow rate (from +3.66 ml/s, 95% CI 2.8–4.5 to +4.14 ml/s, 95% CI 0.72–7.56 at 12 mo), and postvoid residual volume (−10.10 ml, 95% CI −27.90 to 7.71 at 12 mo). No negative impact was observed on scores for the International Index of Erectile Function-5, Male Sexual Health Questionnaire-Ejaculatory Dysfunction bother and function scales (overall postintervention change in pooled median score of 1.88, 95% CI 1.34–2.42 at the start of follow-up; and 1.04, 95% CI 0.28–1.8 after 1 yr), or the IPSS-Quality of Life questionnaire. Conclusions: Novel uMISTs can yield fast and effective relief of LUTS without affecting patient quality of life. Only Rezūm, UroLift, and PAE had a minimal impact on patients’ sexual function with respect to baseline, especially regarding preservation of ejaculation. Patient summary: We reviewed outcomes for recently introduced ultra-minimally invasive surgical treatments for patients with lower urinary tract symptoms caused by benign prostate enlargement or obstruction. The evidence suggests that these novel techniques are beneficial in terms of controlling symptoms while preserving sexual function. Take Home Message: Novel ultra-minimally invasive treatments can yield fast and effective relief of lower urinary tract symptoms without affecting a patient's quality of life

Outcomes of minimally invasive partial nephrectomy among very elderly patients: Report from the resurge collaborative international database

The aim of the study was to perform a comprehensive investigation of clinical outcomes of robot-assisted partial nephrectomy (RAPN) or laparoscopic partial nephrectomy (LPN) in elderly patients presenting with a renal mass.The REnal SURGery in Elderly (RESURGE) collaborative database was queried to identify patients aged 75 or older diagnosed with cT1-2 renal mass and treated with RAPN or LPN. Study outcomes were: overall complications (OC); warm ischemia time (WIT) and 6-month estimated glomerular filtration rate (eGFR); positive surgical margins (PSM), disease recurrence (REC), cancer-specific mortality (CSM) and other-cause mortality (OCM). Descriptive statistics, Kaplan-Meier, smoothed Poisson plots and logistic and linear regression models (MVA) were used.Overall, 216 patients were included in this analysis. OC rate was 34%, most of them being of low Clavien grade. Median WIT was 17 minutes and median 6-month eGFR was 54 ml/min/1.73 m(2). PSM rate was 5%. After a median follow-up of 20 months, the 5-year rates of REC, CSM and OCM were 4, 4 and 5%, respectively. At MVA predicting perioperative morbidity, RAPN relative to LPN (odds ratio [OR] 0.33; p <0.0001) was associated with lower OC rate. At MVA predicting functional outcomes, RAPN relative to LPN was associated with shorter WIT (estimate [EST]-4.09; p <0.0001), and with higher 6-month eGFR (EST 6.03; p = 0.01).In appropriately selected patients with small renal masses, minimally-invasive PN is associated with acceptable perioperative outcomes. The use of a robotic approach over a standard laparoscopic approach can be advantageous with respect to clinically relevant outcomes, and it should be preferred when available

Transperitoneal vs retroperitoneal minimally invasive partial nephrectomy: comparison of perioperative outcomes and functional follow-up in a large multi-institutional cohort (The RECORD 2 Project)

Background Aim of this study was to evaluate and compare perioperative outcomes of transperitoneal (TP) and retroperitoneal (TR) approaches in a multi-institutional cohort of minimally invasive partial nephrectomy (MI-PN). Material and methods All consecutive patients undergone MI-PN for clinical T1 renal tumors at 26 Italian centers (RECORd2 project) between 01/2013 and 12/2016 were evaluated, collecting the pre-, intra-, and postoperative data. The patients were then stratified according to the surgical approach, TP or RP. A 1:1 propensity score (PS) matching was performed to obtain homogeneous cohorts, considering the age, gender, baseline eGFR, surgical indication, clinical diameter, and PADUA score. Results 1669 patients treated with MI-PN were included in the study, 1256 and 413 undergoing TP and RP, respectively. After 1:1 PS matching according to the surgical access, 413 patients were selected from TP group to be compared with the 413 RP patients. Concerning intraoperative variables, no differences were found between the two groups in terms of surgical approach (lap/robot), extirpative technique (enucleation vs standard PN), hilar clamping, and ischemia time. Conversely, the TP group recorded a shorter median operative time in comparison with the RP group (115 vs 150 min), with a higher occurrence of intraoperative overall, 21 (5.0%) vs 9 (2.1%);p = 0.03, and surgical complications, 18 (4.3%) vs 7 (1.7%);p = 0.04. Concerning postoperative variables, the two groups resulted comparable in terms of complications, positive surgical margins and renal function, even if the RP group recorded a shorter median drainage duration and hospital length of stay (3 vs 2 for both variables),p < 0.0001. Conclusions The results of this study suggest that both TP and RP are feasible approaches when performing MI-PN, irrespectively from tumor location or surgical complexity. Notwithstanding longer operative times, RP seems to have a slighter intraoperative complication rate with earlier postoperative recovery when compared with TP

Probe Automata for Passage Time Specification

Passage time distribution has drawn increasing attention over the past years as an important measure to define and verify service level agreements. The definition of passage time requires the specification of a condition to start/stop the computation, and possibly of a restriction on the system behavior to be considered between start and stop. Different characterizations have been defined in the past, either state-based, action-based or a mix of the two, either for Markov chains, or for stochastic Petri nets and process algebras. In this paper we propose probe automata as a way to specify passage time for GSPNs that allows one to select entering, goal, and forbidden states, as well as paths of interest starting from any reachable state. The specification is in terms of conditions over the current marking, the transition (sequence) being fired, as well as over the marking reached through the firing. Probe automata subsume previous definitions of passage time for GSPNs and for Tagged GSPNs, the extension of GSPNs that was defined in the past for computing passage time of a {em tagged token} in a GSPN