Everything you Want to Know and Never Dared to ask:A Practical Approach to Employing Challenge-Based Learning in Engineering Ethics

Challenge-based learning (CBL) for engineering ethics tasks students with identifying ethical challenges in cooperation with an external partner, e.g., a technology company. As many best-practice parameters of such courses remain unclear, this contribution focuses on a teacher-centric introduction into deploying CBL for engineering ethics. Taking Goodlad's curriculum typology as a point of departure, we discuss practical issues in devising, maintaining and evaluating CBL courses for engineering ethics both in terms of the temporal dimension (before, during and after the course) as well as in terms of the people involved. We will discuss selecting learning objectives, forms of knowledge acquisition, supporting self-organization, and fostering discursive etiquette, as well as cooperative, yet critical attitudes. Additionally, we will delve into strategic matters, e.g., ways to approach potential external partners and maintain fruitful cooperations.</p

Consumer exposure to biocides - identification of relevant sources and evaluation of possible health effects

<p>Abstract</p> <p>Background</p> <p>Products containing biocides are used for a variety of purposes in the home environment. To assess potential health risks, data on products containing biocides were gathered by means of a market survey, exposures were estimated using a worst case scenario approach (screening), the hazard of the active components were evaluated, and a preliminary risk assessment was conducted.</p> <p>Methods</p> <p>Information on biocide-containing products was collected by on-site research, by an internet inquiry as well as research into databases and lists of active substances. Twenty active substances were selected for detailed investigation. The products containing these substances were subsequently classified by range of application; typical concentrations were derived. Potential exposures were then estimated using a worst case scenario approach according to the European Commission's Technical Guidance Document on Risk Assessment. Relevant combinations of scenarios and active substances were identified. The toxicological data for these substances were compiled in substance dossiers. For estimating risks, the margins of exposure (MOEs) were determined.</p> <p>Results</p> <p>Numerous consumer products were found to contain biocides. However, it appeared that only a limited number of biocidal active substances or groups of biocidal active substances were being used. The lowest MOEs for dermal exposure or exposure by inhalation were obtained for the following scenarios and biocides: indoor pest control using sprays, stickers or evaporators (chlorpyrifos, dichlorvos) and spraying of disinfectants as well as cleaning of surfaces with concentrates (hydrogen peroxide, formaldehyde, glutardialdehyde). The risk from aggregate exposure to individual biocides via different exposure scenarios was higher than the highest single exposure on average by a factor of three. From the 20 biocides assessed 10 had skin-sensitizing properties. The biocides isothiazolinone (mixture of 5-chloro-2-methyl-2H-isothiazolin-3-one and 2-methyl-2H-isothiazolin-3-one, CMI/MI), glutardialdehyde, formaldehyde and chloroacetamide may be present in household products in concentrations which have induced sensitization in experimental studies.</p> <p>Conclusions</p> <p>Exposure to biocides from household products may contribute to induction of sensitization in the population. The use of biocides in consumer products should be carefully evaluated. Detailed risk assessments will become available within the framework of the EU Biocides Directive.</p

Organophosphate im Vollblut (Chlorpyrifos, Diazinon, Fenitrothion, Fenthion, Malathion)

Das hier beschriebene Verfahren erlaubt die Bestimmung der Organophosphat-Insektizide Chlorpyrifos, Diazinon, Fenitrothion, Fenthion sowie Malathion im Vollblut. Dabei können arbeitsmedizinisch relevante Expositionen gegenüber diesen Organophosphaten erfasst werden. Hierzu wird EDTA-stabilisiertes Vollblut im Ultraschallbad hämolysiert. Die enthaltenen Organophosphate werden an Kieselgurkartuschen (Extrelut NT 20) angereichert und aufgereinigt. Nach der Elution werden die Analyten im Stickstoffstrom aufkonzentriert. Die Messung erfolgt nach kapillargaschromatographischer Trennung mit einem massenselektiven Detektor und Elektronenstossionisation (EI). Die quantitative Auswertung erfolgt an Kalibriergeraden mittels Vergleichsstandards, die mit Hilfe von gepoolten Humanblut hergestellt werden. Diese Standards werden in gleicher Weise behandelt wie die zu untersuchenden Vollblutproben. Als Interner Standard wird den Blutproben Chlorpyrifos-Diethyl-D10 zugesetzt. Die Nachweisgrenze der Methode liegt für die einzelnen Organophosphate zwischen 0,5 und 2,6 ng pro Liter Blut

Measurements in aircrafts during application of biocides for aircraft disinsection

Pest control operations in aircrafts are necessary to prevent the spreading of insect-transmitted infectious diseases. However, if pesticides are used in flight as sprays health disorders in passengers and crew members cannot be excluded. Measurements were taken during application of different disinsection sprays using the "top-of-descent" technique simulated at ground level in parked aircrafts. Concentrations in the air (during spraying and 40 minutes afterwards) were 21µg/m3/285 µg/m3 for pyrethrins/piperonyl butoxide (median values with SRA spray) and 133µg/m3 (224µg/m3) for d-phenothrin after use on Aircraft Disinsectant Denka ( Arrow Aircraft Disinsection Spray). Maximum amounts inhaled were calculated to be 17-200µg. Concentrations found on interior surfaces differed widely. On vertical surfaces (walls, folding tables, overhead bins) median values varied between <= 2 ng/cm2 and <= 17 ng/cm2 . Concentrations (median values) on seats, headrests and floor were 24-39 ng/cm² (pyrethrins), 144-233 ng/cm2 (piperonyl butoxide) and 219-1005 ng/cm2 (d-phenothrin)

The Emergent Yo-yo Movement of Nuclei Driven by Cytoskeletal Remodeling in Pseudo-synchronous Mitotic Cycles

Many aspects in tissue morphogenesis are attributed to a collective behavior of the participating cells. Yet, the mechanism for emergence of dynamic tissue behavior is not well understood. Here, we report that the “yo-yo”-like nuclear movement in the Drosophila syncytial embryo displays emergent features indicative of collective behavior. Following mitosis, the array of nuclei moves away from the wave front by several nuclear diameters only to return to its starting position about 5 min later. Based on experimental manipulations and numerical simulations, we find that the ensemble of elongating and isotropically oriented spindles, rather than individual spindles, is the main driving force for anisotropic nuclear movement. ELMO-dependent F-actin restricts the time for the forward movement and ELMO- and dia-dependent F-actin is essential for the return movement. Our study provides insights into how the interactions among the cytoskeleton as individual elements lead to collective movement of the nuclear array on a macroscopic scale

Developing a new process to agglomerate secondary raw material fines for recycling in the electric arc furnace - the Fines2EAF project

Recent years have seen a worldwide change in the environmental policy towards circular economy approaches. It is estimated that steel-making activities in Europe produce about 80 million tonnes annually of by-products and waste, equivalent to half of the European steel production, of which more than 10 million tonnes is waste for disposal. This waste of resources and land area is not sustainable and has to be decreased in the future. The Fines2EAF project aims to increase the value of steelmaking residues by internal recycling and (re)use in the form of agglomerates. The benefit of this strategy is threefold: improved utilization of residues, internal recovery of valuable materials and reduction of the amount of dumped materials. The approach followed is the development of an innovative process to produce cement -free agglomerates based on primary and secondary raw material fines, alternative binder systems and a hydraulic stamp press. In addition, a new pre-treatment process for fines based on microwave heating is investigated. The first results of the lab-scale investigation of the fines pre-treatment to reduce the amount of zinc, volatiles and alkalis are presented. Six materials from two steel plants have been tested in a laboratory microwave furnace. Also presented are first results of the agglomeration of fines using a laboratory press