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To facilitate the use of Geant4-DNA for radiation transport simulations in micro- and nanodosimeters, which are physically operated with tissue-equivalent gases such as nitrogen (and propane), this work aims to extend the cross section data available in Geant4-DNA to include those of nitrogen for electron energies ranging from 1 MeV down to the ionisation threshold. To achieve this, interaction cross section data for nitrogen that have been used with the in-house PTB PTra track structure code have been implemented in the current state-of-the-art Geant4-DNA simulation toolkit. An intercomparison has been performed between the two codes to validate this implementation. To quantify the agreement between the cross section models for nitrogen adopted in PTra and those implemented in Geant4-DNA, the simulation results of both codes were analysed using three physical parameters describing the ionisation cluster size distribution (ICSD): mean ionisation cluster size, variance of the cluster size and the probability to obtain a single ionisation within the target. Statistical analysis of the results indicates that the interaction cross section models for nitrogen used in PTra (elastic scattering, impact ionisations and electronic excitations) have been successfully implemented in Geant4-DNA. In addition, simulated ICSDs were compared to those measured with the Jet Counter nanodosimeter for energies between 100 and 2000 eV. For greater energies, the ICRP data for LET and particle range were used as a reference. The modified Geant4-DNA code and data successfully passed all these benchmarks fulfilling the requirement for their public release in the next version of the Geant4 toolkit. • Implementation of electron cross-sections in nitrogen down to ionisation threshold in Geant4-DNA. • Consistency check of Geant4-DNA and PTra Monte Carlo track-structure codes. • Good agreement between results of simulations performed using both codes. [ABSTRACT FROM AUTHOR]

Start-ups in dynamic industries frequently pivot their focus, which can help them develop a clear strategic position and subsequently generate a competitive advantage. Whether to pivot or persevere becomes a real-time, critical, and multifaceted decision involving the founder, firm, and environment, but little is known about this complex interplay. Through an explorative case study, we tracked the founding, survival, and growth of Codigames, a high-performing Valencia-based mobile gaming start-up. We combine entrepreneurial leadership, decision-making, and perspective-taking theories to generate insight into critical moments in the start-up's lifepath, contributing to research on the contextualisation of entrepreneurship decision-making under uncertainty. • Start-ups pivot for competitive advantage. • Entrepreneurial leadership shapes strategic change. • Perspective-taking aids decision-making in uncertainty. • Mobile-gaming industry's rapid growth post-COVID-19. [ABSTRACT FROM AUTHOR]

• "dsbandrepair" a Monte Carlo simulation tool based on Geant-DNA toolkit. • Calculation of DSB yields and biological endpoints for alpha, proton, and x-ray irradiations. • Calculation of DSB yields, survival probabilities and fraction of un-rejoined DSBs in agreement with experimental data. Interdisciplinary scientific communities have shown large interest to achieve a mechanistic description of radiation-induced biological damage, aiming to predict biological results produced by different radiation quality exposures. Monte Carlo track-structure simulations are suitable and reliable for the study of early DNA damage induction used as input for assessing DNA damage. This study presents the most recent improvements of a Geant4-DNA simulation tool named "dsbandrepair". "dsbandrepair" is a Monte Carlo simulation tool based on a previous code (FullSim) that estimates the induction of early DNA single-strand breaks (SSBs) and double-strand breaks (DSBs). It uses DNA geometries generated by the DNAFabric computational tool for simulating the induction of early single-strand breaks (SSBs) and double-strand breaks (DSBs). Moreover, the new tool includes some published radiobiological models for survival fraction and un-rejoined DSB. Its application for a human fibroblast cell and human umbilical vein endothelial cell containing both heterochromatin and euchromatin was conducted. In addition, this new version offers the possibility of using the new IRT-syn method for computing the chemical stage. The direct and indirect strand breaks, SSBs, DSBs, and damage complexity obtained in this work are equivalent to those obtained with the previously published simulation tool when using the same configuration in the physical and chemical stages. Simulation results on survival fraction and un-rejoined DSB are in reasonable agreement with experimental data. "dsbandrepair" is a tool for simulating DNA damage and repair, benchmarked against experimental data. It has been released as an advanced example in Geant4.11.2. [ABSTRACT FROM AUTHOR]

This paper demonstrates the impact of the pre-chemical stage, especially the dissociation scheme and the associated probabilities, on water radiolysis simulation using the Geant4-DNA Monte Carlo track structure simulation toolkit. The models and parameters provided by TRACs have been collected and implemented into Geant4-DNA. In order to evaluate their influence on water radiolysis simulation, the radiochemical yields (G-values) are evaluated as a function of time and LET using the "chem6" Geant4-DNA example, and they are compared with published experimental and calculated data. The new pre-chemical models lead to a better agreement with literature data than the default pre-chemical models of Geant4-DNA, especially for OH radicals and H 2 O 2. The revised chemistry constructor "G4EmDNAChemistry_option3" is available in Geant4-DNA version 10.7. [ABSTRACT FROM AUTHOR]

• Realistic dose enhancement of gold nanoparticles for X-rays with secondary particle equilibrium. • Novel approach to estimate uncertainty of correction for lack of secondary particle equilibrium. • Set of consistency checks allowed identifying and correcting normalization problems. • Good agreement of dose enhancement ratios for extended field within uncertainty of correction. • DERs deviate from unity only within the first few 100 nm and maximum values are below 20. Results of a Monte Carlo code intercomparison exercise for simulations of the dose enhancement from a gold nanoparticle (GNP) irradiated by X-rays have been recently reported. To highlight potential differences between codes, the dose enhancement ratios (DERs) were shown for the narrow-beam geometry used in the simulations, which leads to values significantly higher than unity over distances in the order of several tens of micrometers from the GNP surface. As it has come to our attention that the figures in our paper have given rise to misinterpretation as showing 'the' DERs of GNPs under diagnostic X-ray irradiation, this article presents estimates of the DERs that would have been obtained with realistic radiation field extensions and presence of secondary particle equilibrium (SPE). These DER values are much smaller than those for a narrow-beam irradiation shown in our paper, and significant dose enhancement is only found within a few hundred nanometers around the GNP. The approach used to obtain these estimates required the development of a methodology to identify and, where possible, correct results from simulations whose implementation deviated from the initial exercise definition. Based on this methodology, literature on Monte Carlo simulated DERs has been critically assessed. [ABSTRACT FROM AUTHOR]

• EURADOS organized an inter-code intercomparison of dose enhancement of gold nanoparticles irradiated by kVp X-ray spectra. • Variations and uncertainties of dose enhancement are observed by using multiple Monte Carlo codes. • This study gives a reference range of dose enhancement in simulating gold nanoparticles irradiated by x-ray spectra. • This intercomparison improved the simulation performances by identifying differences in settings, scoring and analysis. • Further inter-code intercomparisons ensure a high quality of dose assessment for gold nanoparticle-assisted radiotherapy. [ABSTRACT FROM AUTHOR]

To ascertain the phenomenological characterisation of catatonia in N -methyl- d -aspartate receptor antibody encephalitis (NMDAr-AbE). A systematic review of case reports was undertaken in accordance with PRISMA guidelines. Case reports of NMDAr-AbE containing sufficient information on the cases' clinical presentation and meeting the study's inclusion criteria were selected. Cases were searched for clinical data in keeping with core catatonic signs by applying the screening instrument of the Bush-Francis Catatonia Rating Scale. When two or more core signs were ascertained catatonia was considered to be present. 2645 records were identified through the database search. Following screening and application of eligibility/inclusion criteria 139 articles were selected reporting on 189 individual subjects. Catatonia was present in 60% of these cases. The most prevalent signs were immobility/stupor (70%), mutism (67%), excitement (50%), posturing/catalepsy (34%), stereotypies (31%), and rigidity (30%). Immobility/stupor and excitement co-occurred in the same patient in 33% of cases. The phenomenological profile of catatonia in this sample of cases of NMDAr-AbE was characterised by a preponderance of signs in the hypokinetic spectrum. However, excitement often co-occurred in these patients suggesting that fluctuations in catatonic semiology may be frequent. [ABSTRACT FROM AUTHOR]

Background: Anxiety disorders are recognized as one of the most prevalent mental disorders in late-life. However, the prevalence of anxiety disorders in older Spanish people has not yet been determined. The aim was to review epidemiological studies systematically to calculate the overall prevalence of anxiety in Spanish older adults by using meta-analytic techniques.Methods: We searched relevant published studies in electronic databases up to January 2018 providing data on the prevalence of anxiety among people aged 65+  years in Spain. Overall anxiety prevalence estimates were calculated using random-effects models. Sources of heterogeneity were explored by means of univariate meta-regressions.Results: A total of 9 studies were included in the meta-analysis (N = 12,577). Pooled overall prevalence of anxiety was 11% (95% confidence interval (CI): 6%-18%) representing 1958,471 people aged 65+  (95%CI: 1068,257-3204,771). Point, 12-month and lifetime prevalence of anxiety disorders were 12%, 6% and 19%, respectively.Limitations: We detected a small publication bias effect for life-time prevalence of anxiety. The use of different diagnostic methods across the studies would have required separate analyzes.Conclusion: Some heterogeneity was found across studies, probably due to different methodological issues. Overall, the pooled prevalence of anxiety disorders in Spanish older adults was lower than that observed in other countries. Due to the negative consequences of anxiety disorders in older adults, detection and treatment should be a priority in this population. [ABSTRACT FROM AUTHOR]

The configuration of urban projects using Information and Communication Technologies is an essential aspect in the education of future architects. Students must know the technologies that will facilitate their academic and professional development, as well as anticipating the needs of the citizens and the requirements of their designs. In this paper, a data mining approach was used to outline the strategic requirements for an urban design project in an architecture course using a Project-Based Learning strategy. Informal data related to an award-winning public space (Gillett Square in London, UK) was retrieved from two social networks (Flickr and Twitter), and from its official website. The analysis focused on semantic, temporal and spatial patterns, aspects generally overlooked in traditional approaches. Text-mining techniques were used to relate semantic and temporal data, focusing on seasonal and weekly (work-leisure) cycles, and the geographic patterns were extracted both from geotagged pictures and by geocoding user locations. The results showed that it is possible to obtain and extract valuable data and information in order to determine the different uses and architectural requirements of an urban space, but such data and information can be challenging to retrieve, structure, analyze and visualize. The main goal of the paper is to outline a strategy and present a visualization of the results, in a way designed to be attractive and informative for both students and professionals – even without a technical background – so the conducted analysis may be reproducible in other urban data contexts. [ABSTRACT FROM AUTHOR]