Reactive Turing Machines

We propose reactive Turing machines (RTMs), extending classical Turing machines with a process-theoretical notion of interaction, and use it to define a notion of executable transition system. We show that every computable transition system with a bounded branching degree is simulated modulo divergence-preserving branching bisimilarity by an RTM, and that every effective transition system is simulated modulo the variant of branching bisimilarity that does not require divergence preservation. We conclude from these results that the parallel composition of (communicating) RTMs can be simulated by a single RTM. We prove that there exist universal RTMs modulo branching bisimilarity, but these essentially employ divergence to be able to simulate an RTM of arbitrary branching degree. We also prove that modulo divergence-preserving branching bisimilarity there are RTMs that are universal up to their own branching degree. Finally, we establish a correspondence between executability and finite definability in a simple process calculus

The transrectus sheath preperitoneal mesh repair for inguinal hernia: technique, rationale, and results of the first 50 cases

Item does not contain fulltextINTRODUCTION: Laparoscopic and endoscopic hernia repair popularized the preperitoneal mesh position due to promising results concerning less chronic pain. However, considerable proportions of severe adverse events, learning curves, or added costs have to be taken into account. Therefore, open preperitoneal mesh techniques may have more advantages. The open approach to the preperitoneal space (PPS) according to transrectus sheath preperitoneal (TREPP) mesh repair is through the sheath of the rectus abdominus muscle. This technique provides an excellent view of the PPS and facilitates elective or acute hernia reduction and mesh positioning under direct vision. In concordance with the promising transinguinal preperitoneal inguinal hernia repair experiences in the literature, we investigated the feasibility of TREPP. METHODS: A rationale description of the surgical technique, available level of evidence for thoughts behind technical considerations. Furthermore, a descriptive report of the clinical outcomes of our pilot case series including 50 patients undergoing the TREPP mesh repair. RESULTS: A consecutive group of our first 50 patients were operated with the TREPP technique. No technical problems were experienced during the development of this technique. No conversions to Lichtenstein repair were necessary. No recurrences and no chronic pain after a mean follow-up of 2 years were notable findings. CONCLUSION: This description of the technique shows that the TREPP mesh repair might be a promising method because of the complete preperitoneal view, the short learning curve, and the stay-away-from-the-nerves principle. The rationale of the TREPP repair is discussed in detail.1 juni 201

Expressiveness modulo Bisimilarity of Regular Expressions with Parallel Composition (Extended Abstract)

The languages accepted by finite automata are precisely the languages denoted by regular expressions. In contrast, finite automata may exhibit behaviours that cannot be described by regular expressions up to bisimilarity. In this paper, we consider extensions of the theory of regular expressions with various forms of parallel composition and study the effect on expressiveness. First we prove that adding pure interleaving to the theory of regular expressions strictly increases its expressiveness up to bisimilarity. Then, we prove that replacing the operation for pure interleaving by ACP-style parallel composition gives a further increase in expressiveness. Finally, we prove that the theory of regular expressions with ACP-style parallel composition and encapsulation is expressive enough to express all finite automata up to bisimilarity. Our results extend the expressiveness results obtained by Bergstra, Bethke and Ponse for process algebras with (the binary variant of) Kleene's star operation.Comment: In Proceedings EXPRESS'10, arXiv:1011.601

Larotrectinib efficacy and safety in TRK fusion cancer: An expanded clinical dataset showing consistency in an age and tumor agnostic approach

Background: TRK fusion cancer results from gene fusions involving NTRK1, NTRK2 or NTRK3. Larotrectinib, the first selective TRK inhibitor, has demonstrated an overall response rate (ORR) of 75% with a favorable safety profile in the first 55 consecutively enrolled adult and pediatric patients with TRK fusion cancer (Drilon et al.,NEJM2018). Here, we report the clinical activity of larotrectinib in an additional 35 TRK fusion cancer patients and provide updated follow-up of the primary analysis set (PAS) of 55 patients as of 19thFeb 2018. Methods: Patients with TRK fusion cancer detected by molecular profiling from 3 larotrectinib clinical trials (NCT02122913, NCT02637687, and NCT02576431) were eligible.Larotrectinib was administered until disease progression, withdrawal, or unacceptable toxicity. Disease status was assessed using RECIST version 1.1. Results: As of Feb 2018, by independent review, 6 PRs in the PAS deepened to CRs. The median duration of response (DoR) and progression-free survival in the PAS had still not been reached, with 12.9 months median follow-up. At 1 year, 69% of responses were ongoing, 58% of patients remained progression-free and 90% of patients were alive. An additional 19 children and 25 adults (age range, 0.1-78 years) with TRK fusion cancer were enrolled after the PAS, and included cancers of the salivary gland, thyroid, lung, colon, melanoma, sarcoma, GIST and congenital mesoblastic nephroma. In 35 evaluable patients, the ORR by investigator assessment was 74% (5 CR, 21 PR, 6 SD, 2 PD, 1 not determined). In these patients, with median follow-up of 5.5 months, median DoR had not yet been reached, and 88% of responses were ongoing at 6 months, consistent with the PAS. Adverse events (AEs) were predominantly grade 1, with dizziness, increased AST/ALT, fatigue, nausea and constipation the most common AEs reported in ≥ 10% of patients. No AE of grade 3 or 4 related to larotrectinib occurred in more than 5% of patients. Conclusions: TRK fusions are detected in a broad range of tumor types. Larotrectinib is an effective age- and tumor-agnostic treatment for TRK fusion cancer with a positive safety profile. Screening patients for NTRK gene fusions in solid- and brain tumors should be actively considered

Seasonal Association of Pediatric Functional Abdominal Pain Disorders and Anxiety

Objectives: Abdominal pain-related pediatric functional gastrointestinal disorders (AP-FGIDs) are defined by abdominal discomfort or pain that may provide obstacles to everyday activities, such as school attendance. It has been reported that AP-FGID symptoms may be reduced in summer, but it is unclear what drives this seasonal variation. This pilot study aimed to explore whether the seasonal variation in AP-FGID symptoms could be explained by various psychological and behavioral factors. Methods: Parents of children with AP-FGID symptoms completed online questionnaires on symptoms, anxiety, parental responses to pain, sleep, diet, and physical activity once during spring months and again in the summer months. Results: In a sample of 34 participants who completed both questionnaires, 22 reported improvements during the summer months. These participants reported a significantly higher seasonal decrease in anxiety than participants whose children's symptoms did not improve from spring to summer (mean decrease 2.21 vs 0.08, P = 0.017). Both groups reported equal improvements in sleep and decreased stress from spring to summer. Neither group experienced statistically significant seasonal change in physical activity or fruit, vegetables, dairy, or caffeine consumption. Conclusions: This study suggests that amelioration of gastrointestinal symptoms in pediatric patients with AP-FGID during summer months is associated with amelioration of anxiety in the same time period. It is not yet clear whether decreased anxiety is the cause or effect of decreased AP-FGID symptoms

Recent Onderzoek: Een slechter gehoor leidt tot meer eenzaamheid, maar niet bij alle ouderen

Bespreking recent onderzoek Marieke Pronk, Dorly J.H. Deeg, Cas Smits, Theo G. van Tilburg, Dirk J. Kuik, Joost M. Festen, Sophia E. Kramer (2011). Prospective effects of hearing status on loneliness and depression in older persons: Identification of subgroups. International Journal of Audiology, 50: 887-896

Commissioning and performance of the LHCb Silicon Tracker

The LHCb Silicon Tracker is a silicon micro-strip detector with a sensitive area of 12 m2 and a total of 272k readout channels. The Silicon Tracker consists of two parts that use different detector modules. The detector installation was completed by early summer 2008 and the commissioning without beam has reached its final stage, successfully overcoming most of the encountered problems. Currently, the detector has more than 99% of the channels fully functioning. Commissioning with particles has started using beam-induced events from the LHC injection tests in 2008 and 2009. These events allowed initial studies of the detector performance. Especially, the detector modules could be aligned with an accuracy of about 20μm. Furthermore, with the first beam collisions that took place end of 2009 we could further study the performance and improve the alignment of the detector

De impact van de versoepeling van het bezoekverbod op bewoners van verpleeghuizen en woonzorgcentra: Een vergelijking tussen mei en juni/juli 2020

Deze factsheet beschrijft de situatie van bewoners in instellingen voor verpleging en verzorging tijdens en na het beëindigen van het landelijke bezoekverbod in 2020. In mei en juni/juli is online vragenlijst onderzoek uitgevoerd naar de gevolgen van sociale isolatie door het nieuwe coronavirus in verpleeghuizen en woonzorgcentra. Voor beide metingen zijn deelnemers (bewoners, familieleden en zorgmedewerkers) onafhankelijk van elkaar geworven. Over het algemeen werd kwaliteit van leven in juni/juli vaker belangrijk gevonden dan veiligheid, en leken deelnemers meer bereid dan in mei om het risico van besmettingen te accepteren door bezoek toe te laten. Hoewel bewoners weer twee tot drie keer per week bezoek konden ontvangen, waren zij niet per se minder eenzaam. Wel werden positieve veranderingen in stemming en gedragsproblemen van bewoners gerapporteerd door familieleden en medewerkers. Ook kwaliteit van leven van bewoners werd beter gewaardeerd dan tijdens het bezoekverbod, maar was nog niet op het niveau als vóór het bezoekverbod. De positieve impact van de versoepeling van het bezoekverbod op bewoners, was al na een relatief korte periode zichtbaar. De resultaten ondersteunen de beslissing geen landelijk bezoekverbod meer in te stellen