Cognitive and brain aging is strongly influenced by everyday settings such as work demands. Long-term exposure to low job complexity, for instance, has detrimental effects on cognitive functioning ...and regional gray matter (GM) volume. Brain and cognition, however, are also characterized by plasticity. We postulate that the experience of novelty (at work) is one important trigger of plasticity. We investigated the cumulative effect of recurrent exposure to work-task changes (WTC) at low levels of job complexity on GM volume and cognitive functioning of middle-aged production workers across a time window of 17 years. In a case-control study, we found that amount of WTC was associated with better processing speed and working memory as well as with more GM volume in brain regions that have been associated with learning and that show pronounced age-related decline. Recurrent novelty at work may serve as an '
' intervention that helps counteracting debilitating long-term effects of low job complexity.
Flowering is an important agronomic trait that often depends on the integration of photoperiod, vernalization, gibberellin and/or autonomous signaling pathways by regulatory proteins such as ...FLOWERING LOCUS T (FT), a member of the phosphatidylethanolamine‐binding protein (PEBP) family. Six PEBP family proteins control flowering in the model plant Arabidopsis thaliana, and their regulatory functions are well established, but variation in the number and structural diversity of PEBPs in different species means their precise functions must be determined on a case‐by‐case basis. We isolated four novel FT‐like genes from Nicotiana tabacum (tobacco), and determined their expression profiles in wild‐type plants and their overexpression phenotypes in transgenic plants. We found that all four genes were expressed in leaves under short‐day conditions, and at least NtFT3 expression was restricted to phloem companion cells. We also found that the NtFT1, NtFT2 and NtFT3 proteins are floral inhibitors (atypical for FT‐like proteins), whereas only NtFT4 is a floral inducer. We were unable to detect the expression of these genes under long‐day conditions, suggesting that all four tobacco FT‐like proteins may control flowering in response to short days. Phylogenetic analysis of PEBP family proteins and their functions in different solanaceous species confirmed that gene duplication and divergence within the FT‐like clade has led to the evolution of antagonistic regulators that may help to fine‐tune floral initiation in response to environmental cues.
Evaluating chemical exposures from consumer products is an essential part of chemical safety assessments under REACH and may also be important to demonstrate compliance with consumer product ...legislation. Modelling of consumer exposure needs input information on the substance (e.g. vapour pressure), the product(s) containing the substance (e.g. concentration) and on consumer behaviour (e.g. use frequency and amount of product used). This feasibility study in Germany investigated methods for conducting a consumer survey in order to identify and retrieve information on frequency, duration, use amounts and use conditions for six example product types (four mixtures, two articles): hand dishwashing liquid, cockpit spray, fillers, paints and lacquers, shoes made of rubber or plastic, and ball-pens/pencils. Retrospective questionnaire methods (Consumer Product Questionnaire (CPQ), and Recall-Foresight Questionnaire (RFQ)) as well as protocol methods (written reporting by participants and video documentation) were used. A combination of retrospective questionnaire and written protocol methods was identified to provide valid information in a resource-efficient way. Relevant information, which can readily be used in exposure modelling, was obtained for all parameters and product types investigated. Based on the observations in this feasibility study, recommendations are given for designing a large consumer survey.
Heavy metals from natural and man-made sources can be a great threat to human and animal life. As small inorganic ions they are challenging to detect, usually requiring expensive and complicated ...machinery. Several heavy metals can accumulate in the human body, leading to long term toxic effects on the nervous system. Many bacteria have developed strategies to survive in heavy metal rich environments. One of these strategies is a bacterial operon containing genes for detoxification mechanisms controlled by a promoter and a regulatory protein. In this work some of these promoter-protein pairs, Pars-ArsR, PcopA-CueR, PmerTPAD-MerR and PzntA-ZntR from Escherichia coli have been employed in the design and construction of a set of biosensors aimed at the detection of heavy metals in drinking water. Biosensors usually employ biological recognition elements, transducing the signal from these to produce an output that can be integrated into electronic circuitry. The sensors presented in this work focus on reducing complexity and on providing a controlled sensor reaction. The arsenic biosensor ‘AsGard’ is based on the Pars-ArsR pair and functions by making the dissociation of an ArsR-mCherry fusion protein from its binding site in the Pars promoter visible. In the cell, ArsR dissociates from Pars upon binding of trivalent arsenic ions. Immobilising the relevant part of the Pars sequence on a solid plastic support allows for the mobilisation of previously bound ArsR-mCherry proteins in the presence of arsenic to become the sensor output. The AsGard sensor detects arsenic within minutes in a concentration range overlapping with the arsenic thresholds for drinking water as set by the World Health Organisation. Additional prototype sensors are presented bringing a reporter gene under the control of the aforementioned promoters. These sensors have been tested in vivo and in vitro in a cell free transcription translation system and partially detect metal concentrations close to relevant ranges. The Pars based sensor is tuneable in vitro by modifying the ratio of the supplied regulatory protein ArsR and is able to detect arsenic well within the relevant range. Spinach2, a fluorescent RNA aptamer, may make future designs independent from translation, drastically reducing complexity of cell free biosensors based on cis-trans transcriptional regulation.
Group decision making has attracted much scientific interest, but few studies have investigated group decisions that do not get made. Based on the Motivated Information Processing in Groups model, ...this study analysed the effect of epistemic motivation (low vs. high) and social motivation (proself vs. prosocial) on group decision refusal (the decision to delay choice and refuse all options). In a laboratory experiment, groups had to negotiate diverse preferences and choose one of three options or refuse all. When epistemic motivation was low decisions were made quickly, whereas high epistemic motivation more often led to refusal. This effect was partly mediated by perceived information insufficiency. Social motivation did not affect refusal, but proself motivation led to longer discussions, greater task conflict and more forcing behavior than prosocial motivation. Further, forcing was negatively related to decision refusal, but only when epistemic motivation was low.
The European Food Safety Authority (EFSA) commissioned RPA Europe and FoBiG to carry out the study ‘Mapping of data requirements and assessment methodologies linked to the regulatory frameworks and ...remits of the relevant EU Agencies (ECHA, EFSA and EMA) and EC Scientific Committees (Scientific Committee on Consumer Safety, SCCS, and Scientific Committee on Health, Environmental and Emerging Risks, SCHEER)’ (service contract OC/EFSA/FIP/2022/01 managed by the EFSA Unit on Food Ingredients and Packaging). The general objective was to collect and analyse data requirements (DRs) and risk assessment methodologies (RAMs) applied within the regulatory frameworks of EFSA, the European Chemicals Agency (ECHA), the European Medicines Agency (EMA), SCCS and SCHEER. For comparative analysis, a digital data inventory containing 230 records on legal acts, guidance and other documents related to DRs and RAMs was developed. Based on a comparative analysis methodology, the database of DRs and RAMs across different regulatory frameworks was created by extracting information on DRs (with respect to substance identity, physico‐chemical and environmental fate properties as well as ecotoxicity and toxicity and target organism safety) and RAMs (for the environment, human health and target organisms) from relevant documents. The study identified inconsistencies within regulatory areas in some cases, e.g. between legal acts and guidance documents. Furthermore, it found differences between regulatory frameworks in the DRs and RAMs with respect to terminology, general and detailed DRs and RAMs, the quality standards for experimental studies and other issues. Based on the identified differences and the potential for harmonisation across the regulatory frameworks, several recommendations were outlined in the study that involve addressing specific as well as more principal and structural differences.
An oral dose of 1000 mg/kg body weight/day is mentioned in Organisation for Economic Cooperation and Development (OECD) and European Union (EU) guidelines as a default maximum dose in limit tests for ...studies on reproductive toxicity. This paper investigated whether upper range human exposure data from the workplace are supportive of this limit dose as an upper limit of possible human exposure. To this end, published exposure data as well as data from the database MEGA of the German “Berufsgenossenschaften” were evaluated. These data indicate that exposure concentrations in the range of 500 to 2000 mg/m3 (time-weighted averages) can be considered high human exposures to volatile compounds. Inhalation exposure to aerosols and dermal exposure result in lower dose levels. By applying suitable extrapolation factors, it was concluded that occupational exposures up to 325 mg/m3 can reliably be assessed with limit tests using a dose level of 1000 mg/kg/day. The limit dose has been proposed for use in the EU as a starting point to derive specific concentration limits for hazard classification of preparations containing reproductive toxicants, with the objective to consider the potency of the substances. This analysis shows that for some groups of chemicals, instead of the limit dose, the putative maximum levels of human exposure should be taken into account when deriving concentration limits for the classification of preparations. Furthermore, possible deviations from a linear correlation between concentration in the preparation and exposure should be considered.
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