Perception of Nuclear Energy and Coal in France and the Netherlands

This study focuses on the perception of large scale application of nuclear energy and coal in the Netherlands and France. The application of these energy-sources and the risks and benefits are judged differently by various group in society. In Europe, France has the highest density of nuclear power plants and the Netherlands has one of the lowest. In both countries scientists and social scientists completed a questionnaire assessing the perception of the large scale application of both energy sources. Furthermore, a number of variables relating to the socio cultural and political circumstances were measured. The results indicate that the French had a higher risk perception and a more negative attitude toward nuclear power than the Dutch. But they also assess the benefits of the use of nuclear power to be higher. Explanations for these differences are discussed

Experimental study of pedestrian flow through a bottleneck

In this work the results of a bottleneck experiment with pedestrians are presented in the form of total times, fluxes, specific fluxes, and time gaps. A main aim was to find the dependence of these values from the bottleneck width. The results show a linear decline of the specific flux with increasing width as long as only one person at a time can pass, and a constant value for larger bottleneck widths. Differences between small (one person at a time) and wide bottlenecks (two persons at a time) were also found in the distribution of time gaps.Comment: accepted for publication in J. Stat. Mec

Parsimony versus reductionism: how can crowd psychology be introduced into computer simulation?

Computer simulations are increasingly being used to predict the behaviour of crowds. However, the models used are mainly based on video observations, not an understanding of human decision making. Theories of crowd psychology can elucidate the factors underpinning collective behaviour in human crowds. Yet, in contrast to psychology, computer science must rely upon mathematical formulations in order to implement algorithms and keep models manageable. Here we address the problems and possible solutions encountered when incorporating social psychological theories of collective behaviour in computer modelling. We identify that one primary issue is retaining parsimony in a model whilst avoiding reductionism by excluding necessary aspects of crowd psychology, such as the behaviour of groups. We propose cognitive heuristics as a potential avenue to create a parsimonious model that incorporates core concepts of collective behaviour derived from empirical research in crowd psychology

Abnormal Regional and Global Connectivity Measures in Subjective Cognitive Decline Depending on Cerebral Amyloid Status

Background: Amyloid-β accumulation was found to alter precuneus-based functional connectivity (FC) in mild cognitive impairment (MCI) and Alzheimer’s disease (AD) dementia, but its impact is less clear in subjective cognitive decline (SCD), which in combination with AD pathologic change is theorized to correspond to stage 2 of the Alzheimer’s continuum in the 2018 NIA-AA research framework. Objective: This study addresses how amyloid pathology relates to resting-state fMRI FC in SCD, especially focusing on the precuneus. Methods: From the DELCODE cohort, two groups of 24 age- and gender-matched amyloid-positive (SCDAβ+) and amyloidnegative SCD (SCDβ−) patients were selected according to visual [18F]-Florbetaben (FBB) PET readings, and studied with resting-state fMRI. Local (regional homogeneity [ReHo], fractional amplitude of low-frequency fluctuations [fALFF]) and global (degree centrality [DC], precuneus seed-based FC) measures were compared between groups. Follow-up correlation analyses probed relationships of group differences with global and precuneal amyloid load, as measured by FBB standard uptake value ratios (SUVR=⫖FBB). Results: ReHo was significantly higher (voxel-wise p < 0.01, cluster-level p < 0.05) in the bilateral precuneus for SCDAβ+patients, whereas fALFF was not altered between groups. Relatively higher precuneus-based FC with occipital areas (but no altered DC) was observed in SCDAβ+ patients. In this latter cluster, precuneus-occipital FC correlated positively with global (SCDAβ+) and precuneus SUVRFBB (both groups). Conclusion: While partial confounding influences due to a higher APOE ε4 carrier ratio among SCDAβ+ patients cannot be excluded, exploratory results indicate functional alterations in the precuneus hub region that were related to amyloid-β load, highlighting incipient pathology in stage 2 of the AD continuum

Impact of complications after resection of pancreatic cancer on disease recurrence and survival, and mediation effect of adjuvant chemotherapy:nationwide, observational cohort study

Background: The causal pathway between complications after pancreatic cancer resection and impaired long-term survival remains unknown. The aim of this study was to investigate the impact of complications after pancreatic cancer resection on disease-free interval and overall survival, with adjuvant chemotherapy as a mediator.Methods: This observational study included all patients undergoing pancreatic cancer resection in the Netherlands (2014-2017). Clinical data were extracted from the prospective Dutch Pancreatic Cancer Audit. Recurrence and survival data were collected additionally. In causal mediation analysis, direct and indirect effect estimates via adjuvant chemotherapy were calculated.Results: In total, 1071 patients were included. Major complications (hazards ratio 1.22 (95 per cent c.i. 1.04 to 1.43); P = 0.015 and hazards ratio 1.25 (95 per cent c.i. 1.08 to 1.46); P = 0.003) and organ failure (hazards ratio 1.86 (95 per cent c.i. 1.32 to 2.62); P &lt; 0.001 and hazards ratio 1.89 (95 per cent c.i. 1.36 to 2.63); P &lt; 0.001) were associated with shorter disease-free interval and overall survival respectively. The effects of major complications and organ failure on disease-free interval (-1.71 (95 per cent c.i. -2.27 to -1.05) and -3.05 (95 per cent c.i. -4.03 to -1.80) respectively) and overall survival (-1.92 (95 per cent c.i. -2.60 to -1.16) and -3.49 (95 per cent c.i. -4.84 to -2.03) respectively) were mediated by adjuvant chemotherapy. Additionally, organ failure directly affected disease-free interval (-5.38 (95 per cent c.i. -9.27 to -1.94)) and overall survival (-6.32 (95 per cent c.i. -10.43 to -1.99)). In subgroup analyses, the association was found in patients undergoing pancreaticoduodenectomy, but not in patients undergoing distal pancreatectomy.Conclusion: Major complications, including organ failure, negatively impact survival in patients after pancreatic cancer resection, largely mediated by adjuvant chemotherapy. Prevention or adequate treatment of complications and use of neoadjuvant treatment may improve oncological outcomes.</p

Predicting Long-term Disease-free Survival after Resection of Pancreatic Ductal Adenocarcinoma:A Nationwide Cohort Study

Objective: To develop a prediction model for long-term (≥5 years) disease-free survival (DFS) after the resection of pancreatic ductal adenocarcinoma (PDAC). Background: Despite high recurrence rates, 10% of patients have long-term DFS after PDAC resection. A model to predict long-term DFS may aid individualized prognostication and shared decision-making. Methods: This nationwide cohort study included all consecutive patients who underwent PDAC resection in the Netherlands (2014-2016). The best-performing prognostic model was selected by Cox-proportional hazard analysis and Akaike's Information Criterion, presented by hazard ratios (HRs) with 95% confidence intervals (CIs). Internal validation was performed, and discrimination and calibration indices were assessed. Results: In all, 836 patients with a median follow-up of 67 months (interquartile range 51-79) were analyzed. Long-term DFS was seen in 118 patients (14%). Factors predictive of long-term DFS were low preoperative carbohydrate antigen 19-9 (logarithmic; HR 1.21; 95% CI 1.10-1.32), no vascular resection (HR 1.33; 95% CI 1.12-1.58), T1 or T2 tumor stage (HR 1.52; 95% CI 1.14-2.04, and HR 1.17; 95% CI 0.98-1.39, respectively), well/moderate tumor differentiation (HR 1.44; 95% CI 1.22-1.68), absence of perineural and lymphovascular invasion (HR 1.42; 95% CI 1.11-1.81 and HR 1.14; 95% CI 0.96-1.36, respectively), N0 or N1 nodal status (HR 1.92; 95% CI 1.54-2.40, and HR 1.33; 95% CI 1.11-1.60, respectively), R0 resection margin status (HR 1.25; 95% CI 1.07-1.46), no major complications (HR 1.14; 95% CI 0.97-1.35) and adjuvant chemotherapy (HR 1.74; 95% CI 1.47-2.06). Moderate performance (concordance index 0.68) with adequate calibration (slope 0.99) was achieved. Conclusions: The developed prediction model, readily available at www.pancreascalculator.com, can be used to estimate the probability of long-term DFS after resection of pancreatic ductal adenocarcinoma.</p

Preoperative predictors for early and very early disease recurrence in patients undergoing resection of pancreatic ductal adenocarcinoma

BACKGROUND: This study aimed to identify predictors for early and very early disease recurrence in patients undergoing resection of pancreatic ductal adenocarcinoma (PDAC) resection with and without neoadjuvant therapy. METHODS: Included were patients who underwent PDAC resection (2014-2016). Multivariable multinomial regression was performed to identify preoperative predictors for manifestation of recurrence within 3, 6 and 12 months after PDAC resection. RESULTS: 836 patients with a median follow-up of 37 (interquartile range [IQR] 30-48) months and overall survival of 18 (IQR 10-32) months were analyzed. 670 patients (80%) developed recurrence: 82 patients (10%) <3 months, 96 patients (11%) within 3-6 months and 226 patients (27%) within 6-12 months. LogCA 19-9 (OR 1.25 [95% CI 1.10-1.41]; P < 0.001) and neoadjuvant treatment (OR 0.09 [95% CI 0.01-0.68]; P = 0.02) were associated with recurrence <3 months. LogCA 19-9 (OR 1.23 [95% CI 1.10-1.38]; P < 0.001) and 0-90° venous involvement on CT imaging (OR 2.93 [95% CI 1.60-5.37]; P < 0.001) were associated with recurrence within 3-6 months. A Charlson Age Comorbidity Index ≥4 (OR 1.53 [95% CI 1.09-2.16]; P = 0.02) and logCA 19-9 (OR 1.24 [95% CI 1.14-1.35]; P < 0.001) were related to recurrence within 6-12 months. CONCLUSION: This study demonstrates preoperative predictors that are associated with the manifestation of early and very early recurrence after PDAC resection. Knowledge of these predictors can be used to guide individualized surveillance and treatment strategies

Predicting overall survival and resection in patients with locally advanced pancreatic cancer treated with FOLFIRINOX:Development and internal validation of two nomograms

Background and Objectives Patients with locally advanced pancreatic cancer (LAPC) are increasingly treated with FOLFIRINOX, resulting in improved survival and resection of tumors that were initially unresectable. It remains unclear, however, which specific patients benefit from FOLFIRINOX. Two nomograms were developed predicting overall survival (OS) and resection at the start of FOLFIRINOX for LAPC. Methods From our multicenter, prospective LAPC registry in 14 Dutch hospitals, LAPC patients starting first-line FOLFIRINOX (April 2015-December 2017) were included. Stepwise backward selection according to the Akaike Information Criterion was used to identify independent baseline predictors for OS and resection. Two prognostic nomograms were generated. Results A total of 252 patients were included, with a median OS of 14 months. Thirty-two patients (13%) underwent resection, with a median OS of 23 months. Older age, female sex, Charlson Comorbidity Index 1, involvement of the superior mesenteric artery, celiac trunk, and superior mesenteric vein >= 270 degrees were independent factors decreasing the probability of resection (c-index: 0.79). Conclusions Two nomograms were developed to predict OS and resection in patients with LAPC before starting treatment with FOLFIRINOX. These nomograms could be beneficial in the shared decision-making process and counseling of these patients

Detection, Treatment, and Survival of Pancreatic Cancer Recurrence in the Netherlands A Nationwide Analysis

OBJECTIVE: To evaluate whether detection of recurrent pancreatic ductal adenocarcinoma (PDAC) in an early, asymptomatic stage increases the number of patients receiving additional treatment, subsequently improving survival. SUMMARY OF BACKGROUND DATA: International guidelines disagree on the value of standardized postoperative surveillance for early detection and treatment of PDAC recurrence. METHODS: A nationwide, observational cohort study was performed including all patients who underwent PDAC resection (2014-2016). Prospective baseline and perioperative data were retrieved from the Dutch Pancreatic Cancer Audit. Data on follow-up, treatment, and survival were collected retrospectively. Overall survival (OS) was evaluated using multivariable Cox regression analysis, before and after propensity-score matching, stratified for patients with symptomatic and asymptomatic recurrence. RESULTS: Eight hundred thirty-six patients with a median follow-up of 37 months (interquartile range 30-48) were analyzed. Of those, 670 patients (80%) developed PDAC recurrence after a median follow-up of 10 months (interquartile range 5-17). Additional treatment was performed in 159/511 patients (31%) with symptomatic recurrence versus 77/159 (48%) asymptomatic patients (P < 0.001). After propensity-score matching on lymph node ratio, adjuvant therapy, disease-free survival, and recurrence site, additional treatment was independently associated with improved OS for both symptomatic patients [hazard ratio 0.53 (95% confidence interval 0.42-0.67); P < 0.001] and asymptomatic patients [hazard ratio 0.45 (95% confidence interval 0.29-0.70); P < 0.001]. CONCLUSIONS: Additional treatment of PDAC recurrence was independently associated with improved OS, with asymptomatic patients having a higher probability to receive recurrence treatment. Therefore, standardized postoperative surveillance aiming to detect PDAC recurrence before the onset of symptoms has the potential to improve survival. This provides a rationale for prospective studies on standardized surveillance after PDAC resection