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Zusammenfassung Hintergrund Die Hüftdysplasie ist eine komplexe statisch-dynamische Pathologie, welche zu chronischer Gelenkinstabilität und Arthrose führt. Das Verständnis der zugrundeliegenden Pathomorphologie hat sich weiterentwickelt, sodass eine Aktualisierung der Definition erforderlich ist. Fragestellung Wie lautet die Definition der Hüftdysplasie im Jahr 2023? Methoden Durch Zusammenfassung und Aufarbeitung der relevanten Literatur wird eine aktuelle Definition der Hüftdysplasie mit konkreten Angaben zur Diagnostik bereitgestellt. Ergebnisse Neben pathognomonischen sind supportive und deskriptive Parameter, sowie sekundäre Veränderungen von zentraler Bedeutung zur Diagnose der Hüftinstabilität. Die diagnostische Basis ist die konventionelle Beckenübersichtsaufnahme, welche bei Bedarf durch Zusatzuntersuchungen (Arthro-MRT der Hüfte; CT) ergänzt wird. Schlussfolgerung Die Komplexität, Subtilität und Vielfalt der Pathomorphologie residueller Hüftdysplasien erfordert eine sorgfältige, mehrstufige Diagnostik und Therapieplanung in spezialisierten Zentren.

The increase in evidence on the adverse health effects of air pollution has been possible thanks to the advances in technology for air pollution monitoring and personal exposure. In this context, air quality sensors present a huge potential for enhancing long-term personal exposure prediction. In order to prove the potential of air sensors for health research, a pilot study with patients suffering from chronic obstructive pulmonary diseases or Asthma was carried out in Stuttgart (Germany) in cooperation with the University Hospital Charité in Berlin, and an outpatient pulmonary practice in Stuttgart.Prior to the pilot study, we first tested several sensor models for PM and NO2 in the laboratory as well as in the field. The sensors with the best performance were selected to build two different sensor boxes for indoor and outdoor measurements. Temperature and relative humidity sensors were also included in the boxes. To avoid the overestimation of the PM readings due to hygroscopic growth, a low-cost dryer was designed and evaluated for the PM sensor of the outdoor boxes (Chacón-Mateos et al. 2022).The measurements inside and outside the houses were carried out over 30 days. Passive sampling of NO2 was done additionally for quality assurance of the NO2 measurements. Participants completed spirometry, a questionnaire assessing respiratory symptoms, and a protocol of activities on a daily basis. The calibration and validation of the sensors were conducted two weeks before the start of the measurements. To perform the quality assurance, the sensor boxes for indoors were collocated in the laboratory, and the sensor boxes for outdoors in the field, together with reference-grade instruments. The PM2.5 concentrations were corrected using univariate linear regression whereas multilinear regression and machine learning algorithms were tested and applied to correct the raw data of the NO2 sensors.The sensor validations have shown that measuring low concentrations of PM2.5 and NO2 has higher expanded uncertainty, but high concentrations can be measured with expanded uncertainties that fulfill the Data Quality Objectives (DQO) set by the Air Quality Directives for indicative measurements. However, we also found a high unit-to-unit variability which means that model coefficients cannot be transferred from one sensor to another. We also recommend collocating NO2 passive samples close to the sensor boxes to determine whether or not the sensor is measuring within the expected range as the signal of some NO2 sensors drifted unexpectedly during the measurements in the houses of the patients.In conclusion, air sensors are not yet to be recommended to quantify the effects of low-level air pollution but they are a promising tool to increase the ubiquity of epidemiological studies for low- and middle-income countries where high air pollution is expected. Moreover, it is important to consider that in order to get actionable data with air sensors, a significant amount of time in sensor calibration should be invested.References:Chacón-Mateos, M., Laquai, B., Vogt, U., and Stubenrauch, C.: Evaluation of a low-cost dryer for a low-cost optical particle counter, Atmos. Meas. Tech., 15, 7395–7410, https://doi.org/10.5194/amt-15-7395-2022, 2022

Efficient Process Development by Combining Process Simulation and Miniplant Technique. International competition, growing ever fiercer, and product life cycles which are becoming shorter all the time demand a significant contraction times from the chemical industry, of the implementation times from the conception of a product to its market introduction. A significant contribution to rapid and cost-effective detailed planning of a new production process is provided by the combination of process simulation and an experimental technique developed within BASF AG, i.e. the „miniplant” technique. This article starts by demonstrating the importance of process simulation in the individual phases of process development. It explains the characteristic features of the miniplant technique, what objectives are pursued by employing his technique, and what advantages ccan be achieved, compared with setting up and operating pilot plants. Finally, two examples illustrate that it is possible, by combining process simulation and miniplant technique, to develop processes more rapidely and to scale them up directly from the laboratory to production level.

A novel 2∶1 (permethylated-β-cyclodextrin)–fullerene conjugate has been synthesised; highly soluble in cold water with formation of aggregates, it displays a negative solubility coefficient and has a partition coefficient between octanol and water (Log P = 1.58) in the suitable range for biological studies.

Economic and technological evaluation of processes. The process engineer is finding it increasingly important to evaluate a given process from the economic and technological standpoint, when developing a process or realizing an investment project. In order to demonstrate the possibility of a structured and systematic mode of procedure, a brief account is given of the available tools. Profitability can be evaluated on the basis of the accounting rate of return (ROI), the internal rate of return (dcf yield), and the ratio of equity, all measures that can be derived from an assessment of costs and economics. To take into account the uncertainty of the boundary conditions assumed, such as raw materials costs, selling prices, and plant utilization, it is advisable to carry out a risk and sensitivity analysis. Examples are given that demonstrate the possibility of both calculating and reducing the economic and technological risks.

Various approaches to process intensification can be taken at various levels. At the lowest level, it may be possible to optimise basic physical, thermodynamic and chemical processes, for example, by changing geometries and surface structures, or using catalysts, etc. At the next level, possibilities include the use of cleverly designed plant items such as spiral heat exchangers or centrifugal reactors. Finally, at the highest or process level, improvements may involve carrying out several unit operations simultaneously in a single piece of equipment or making specific process modifications. This paper uses three examples (extractive distillation, reactive distillation column, steam injection) to demonstrate the breadth of possibilities for intensifying chemical processes. The processes were all developed with the help of process simulation and verified experimentally in laboratory-based miniplants. The information gained was essential to the successful design and operation of production-scale plant.

A novel 2:1 (permethylated-beta-cyclodextrin)-fullerene conjugate has been synthesised; highly soluble in cold water with formation of aggregates, it displays a negative solubility coefficient and has a partition coefficient between octanol and water (Log P = 1.58) in the suitable range for biological studies.

Mass transfer between moisture in a packed bed of porous aluminium silicate particles and vapour flowing through it is investigated theoretically and experimentally as well. The vapour and moisture both consist of isopropanol and water. If the inlet composition of the vapour is different from the vapour composition at the particle surface the more volatile component is enriched in the vapour while the latter passes through the bed. By variation of mixture composition, particle size, bed height and flow rate the extent of enrichment can be shown to depend on vapour-liquid phase equilibrium, liquid-phase diffusion inside the particles and gas-phase mass transfer.

The selectivity during the drying of porous materials containing binary mixtures depends on the thermodynamic equilibrium, the gas-side mass transfer and the liquid-side mass transfer. Very often the drying process is nonselective owing to the controlling liquid-side mass transfer. However, in this case at the early stages a selectivity might be expected, because the liquid-side mass transfer resistance is negligible at the beginning. This so-called initial selectivity can be extended to the whole drying process by intermittent drying. For this purpose the time required for the development of the steady state concentration profile at the beginning (transient time t T ) and the time required for the degraation of the steady state concentration profile during recovery (relaxation time t R ) had been estimated theoretically and experimentally in this work.

L'appareil en forme de schema agite mecaniquement, ses parois en cuivre sont chauffees electriquement. On mesure le coefficient de transfert de chaleur en fonction de la dimension des particules (0,5; 1 ; 2 mm) et du gaz circulant (air ou helium)

For vacuum contact drying of mechanically agitated, coarse, hygroscopic bulk material the drying rate and final moisture content can be controlled by a proper choice of drying conditions, mixing intensity and granular bed properties. This is demonstrated by means of theoretical and experimental investigations.