Deutsche Gesetzliche Unfallversicherung

AimsTo compare the accuracy of a mechanobiological simulation against that of clinicians in forecasting long bone nonunions, and to determine whether the simulation’s results can be effectively used as input for a machine-learning algorithm.MethodsThis was a retrospective diagnostic accuracy study using a cohort of 98 patients who underwent surgery for tibial shaft fractures at four tertiary care trauma institutions in Germany between January 2018 and December 2023, 20 of whom developed nonunion. Biplanar pre- and postoperative radiographs and detailed demographic and clinical information (sex, age, BMI, comorbidities, fracture characteristics, surgical protocol, and implants used) were provided to clinicians to predict the likelihood of nonunion. All data were also analyzed with the Leeds-Genoa Non-Union-Index (LEG NUI) and entered into a mechanobiological simulation model, a machine-learning model, and a hybrid model. Performance metrics were then compared across all five assessment methods.ResultsComparing the overall predictive performance of the clinicians’ heuristic, the LEG NUI score, and the three computational models, the hybrid model outperforms all contenders concerning sensitivity (80%), positive predictive value (59%), negative predictive value (94%), and Matthews correlation coefficient (59%). Specificity was high (86%), solely outperformed by the specificity of the LEG NUI score (95%) and the mechanobiological simulation (90%).ConclusionThe AI-based hybrid model outperforms human experts in predicting nonunions in long bone fractures, enabling the early detection of patients at risk and the modification of treatment strategies to improve patient outcomes.Cite this article: Bone Joint Res 2026;15(10):1196–1205.

Cooling vests in occupational heat protection Heat increasingly affects outdoor workers and poses new challenges for occupational safety and health. Cooling vests are increasingly being considered a promising measure to reduce heat strain. But how effective are they under real working conditions? This article presents the results of a field study involving courier drivers and highlights key considerations for the practical implementation of cooling vests in the workplace.

DGUV expert discussion on “Exposure Assessment and Evaluation for Exposure to Benzene (Occupational Disease No. 1318)” Hosted by Katrin Pitzke (IFA) and Dr. Dirk Pallapies (IPA), the DGUV expert discussion on “Exposure Assessment and Evaluation for Exposure to Benzene (Occupational Disease No. 1318)” took place on February 2 and 3, 2026, in Berlin, with the participation of occupational physician experts, representatives of prevention departments and the administrative departments of the German social accident insurance institution, as well as the IPA and IFA. The objective was to exchange experiences and discuss challenges, as well as explore possible solutions regarding the assessment and evaluation of causality for Occupational Disease No. 1318.

Section S-1.Biases in model output arising from averaging ion properties A challenge in predicting particle charge distributions with charging models is that the measured ion properties are widely distributed rather than represented by a single value.In practice, the measured 𝑍 𝑖distribution is often reduced to the concentration-weighted mean mobility 〈𝑍 𝑖 〉. 〈𝑚 𝑖 〉 is either computed from 〈𝑍 𝑖 〉 or directly measured.From these mean ion properties, the mean combination coefficient 〈𝛽〉 is then calculated (Eq. 5 in the main text).However, because 𝛽 depends nonlinearly on 𝑍 𝑖 and 𝑚 𝑖 , and the ion properties are typically widely distributed, using the weighted averages of 𝑍 𝑖 and 𝑚 𝑖 to compute everything else inevitably introduces a bias in 〈𝛽〉, i.e., 〈𝛽(𝑍 𝑖 , 𝑚 𝑖 )〉 ≠ 𝛽(〈𝑍 𝑖 , 𝑚 𝑖 〉).This averaging bias is strongly reduced if ion properties are narrowly distributed, which can for example be reached when introducing VMS to the carrier gas, as shown in the manuscript.Interestingly, in the sub-20 nm regime, which is close to the ion free molecular limit (𝑟 p ≪ 𝜆 i ), the combination coefficient is linearly proportional to the ion mean thermal speed (White, 1951): 𝛽 𝑎≪𝜆 = 𝜋𝑟 p 2 𝑐̅ 𝑖 • 𝜀 -𝑒 2 𝑟 p 𝑘 B 𝑇 , Eq. S-1 which can potentially reduce this averaging error significantly.However, typically ion mass is used as main model input (besides electrical mobility) from which 𝑐̅ 𝑖 is determined.Given that 𝑚 𝑖 and 𝑐̅ 𝑖 are not linearly proportional and therefore 〈𝑐̅ 𝑖 (𝑚 𝑖 )〉 ≠ 𝑐̅ 𝑖 (〈𝑚 𝑖 〉) when averaging wide distributions, a similar averaging error is introduced when using 〈𝑚 𝑖 〉 as model input.For all the model calculations shown in the manuscript, it was therefore important to determine the measured weighted mean of 𝑐̅ 𝑖 as accurately as possible.This was done by converting the measured 𝑍 𝑖distribution into a 𝑐̅ 𝑖 -distribution using the mass-mobility relationship by (Mäkelä et al., 1996) and gas kinetic theory, from which 〈𝑐̅ 𝑖 〉 was determined (Eq.12 in the main text).

Abstract. The sizing of aerosol particles is commonly carried out by electrical techniques, requiring particles to reach a known charge distribution prior to measurement. This is typically achieved by passing the particles through bipolar diffusion chargers, where the resulting steady-state particle charge distribution depends on the properties of the ions therein. We present new measurements of the charge fractions of sub-20 nm particles after bipolar diffusion charging, along with measurements characterizing the properties of ions generated within the bipolar charger. Our results show that, under steady-state conditions, the particle charge distribution is primarily determined by charger ion properties, which can be influenced even by trace gas contamination. Specifically, the use of commonly employed conductive silicone tubing, which emits trace concentrations of volatile methyl siloxanes (VMS), changes the mean positive ion mobility by 20 %, leading to deviations of up to 25 % in the fraction of singly charged particles relative to measurements without the tubing. We further show that the use of conductive silicone tubing stabilizes the mean positive ion mobility to 1.05 ± 0.1 cm2 V−1 s−1associated with VMS. The mobility of the negative ions, on the other hand, remains highly dependent on gas composition. Building on the finding that positive ion properties can be readily stabilized to repeatable values, we show that negative ion properties can be approximated through a simple bipolar Mobility Particle Size Spectrometers (MPSS) measurement. Our measurements show good agreement with charge fractions predicted by Hoppel & Frick theory, with relative differences of up to −6.1 % and 0.6 % for positive and negative charge fractions, respectively, supporting the validity of classical charging theory for sub-20 nm particles. In contrast, significant deviations from the commonly used Wiedensohler (1988) approximation highlight the importance of accounting for environment-specific ion properties when predicting particle charge distributions.

Aerosol samplers have been widely applied to determine dust exposure in workplaces. In this study, a high flow rate respirable size-selective cyclone sampler GK6.27 was developed, computationally investigated, and experimentally tested at a sampling flow rate of 20 l/min. The aspiration efficiency of the GK6.27 sampler in calm air was determined from the simulation of the sampler in a wind tunnel. To ensure accurate aerosol sampling downstream of the cyclone, a 4-way flow splitter was developed. The measured cut-size of the GK6.27 sampler is 4.01 μm, which conforms to the respirable convention EN 481. The sampler performance was assessed using the bias map approach according to EN 13205-2, which showed that the bias in the sampled concentration of the GK6.27 sampler is within ±8% for all 216 aerosol size distributions of interest, with a root mean square bias of 3.48%. Additionally, detailed information on the particles collected on the filter, such as their travelling time and distance, as well as their distribution on the filter, was derived from LES simulations, which were validated based on experimental data.

Berechnungs- und Abrechnungspraxis verstehen Geldleistungen sind neben den Präventions- und Rehabilitationsmaßnahmen ein wesentlicher Leistungsauftrag der gesetzlichen Unfallversicherung (GUV). Unter die Geldleistungen fallen beispielsweise das Verletztengeld, das Übergangsgeld und die Versichertenrente. Eric Zimmermann erklärt alles Wissenswerte über die Geldleistungen im Detail für Studium, Ausbildung und Praxis. Das Buch richtet sich an Studierende und Auszubildende der Gesundheits- und Rechtswissenschaften. Es ist auch für die Praxis, z. B. Unfallversicherungsträger und Krankenkassen, geeignet.