Although most odorants we encounter in daily life are mixtures of several chemical substances, we still lack significant information on how we perceive and how the brain processes mixtures of odorants. We aimed to investigate the processing of odor mixtures using behavioral measures and functional magnetic resonance imaging (fMRI). The odor mixture contained a target odor (ambroxan) in a concentration at which it could be perceived by half of the subjects (sensitive group); the other half could not perceive the odor (insensitive group). In line with previous findings on multi-component odor mixtures, both groups of subjects were not able to distinguish a complex odor mixture containing or not containing the target odor. However, sensitive subjects had stronger activations than insensitive subjects in chemosensory processing areas such as the insula when exposed to the mixture containing the target odor. Furthermore, the sensitive group exhibited larger brain activations when presented with the odor mixture containing the target odor compared to the odor mixture without the target odor; this difference was smaller, though present for the insensitive group. In conclusion, we show that a target odor presented within a mixture of odors can influence brain activations although on a psychophysical level subjects are not able to distinguish the mixture with and without the target. On the practical side these results suggest that the addition of a certain compound to a mixture of odors may not be detected on a cognitive level; however, this additional odor may significantly change the cerebral processing of this mixture. In this context, FMRI offers unique possibilities to look at the subliminal effects of odors.

Extreme haustorial parasites have long captured the interest of naturalists and scientists with their greatly reduced and highly specialized morphology. Along with the reduction or loss of photosynthesis, the plastid genome often decays as photosynthetic genes are released from selective constraint. This makes it challenging to use traditional plastid genes for parasitic plant phylogenetics, and has driven the search for alternative phylogenetic and molecular evolutionary markers. Thus, evolutionary studies, such as molecular clock-based age estimates, are not yet available for all parasitic lineages. In the present study, we extracted 14 nuclear single copy genes (nSCG) from Illumina transcriptome data from one of the “strangest plants in the world”, Hydnora visseri (Hydnoraceae). A ~15,000 character molecular dataset, based on all three genomic compartments, shows the utility of nSCG for reconstructing phylogenetic relationships in parasitic lineages. A relaxed molecular clock approach with the same multi-locus dataset, revealed an ancient age of ~91 MYA for Hydnoraceae. We then estimated the stem ages of all independently originated parasitic angiosperm lineages using a published dataset, which also revealed a Cretaceous origin for Balanophoraceae, Cynomoriaceae and Apodanthaceae. With the exception of Santalales, older parasite lineages tend to be more specialized with respect to trophic level and have lower species diversity. We thus propose the “temporal specialization hypothesis” (TSH) implementing multiple independent specialization processes over time during parasitic angiosperm evolution.

The choice of a meaningful baseline condition is a crucial issue for each experimental design. In the case of cognitive emotion regulation, it is common to either let participants passively view emotional stimuli without any further specific instructions or to instruct them to actively attend to and permit any arising emotions, and to contrast one of these baseline conditions with a regulation condition. While the “view” strategy can be assumed to allow for a more spontaneous emotional response, the “permit” strategy may result in a more pronounced affective and cognitive response. As these conceptual differences may be associated with differences both in subjective emotional experience and neural activation, we compared these two common control conditions within a single functional magnetic resonance imaging (fMRI) experiment, during which participants were instructed to either passively view a set of unpleasant and neutral pictures or to actively permit any emotions arising in response to the unpleasant pictures. Trial-by-trial ratings confirmed that participants perceived the unpleasant pictures as more arousing than the neutral pictures, but also indicated higher subjective arousal during the “permit negative” as compared to the “view negative” and “view neutral” conditions. While both the “permit negative” and “view negative” conditions led to increased activation of the bilateral amygdala when contrasted with the passive viewing of neutral pictures, activation in the left amygdala was increased in response to the “permit” instruction as compared to the “view” instruction for unpleasant pictures. The increase in amygdala activation in both the “permit” and “view” conditions renders both strategies as suitable baseline conditions for studies of cognitive emotion regulation. Conceptual and activation differences, however, indicate that these two variants are not exchangeable and should be chosen depending on the experimental context.

Elevated arsenic content in food crops pose a serious human health risk. Apart from rice wheat being another main food crop is possibly cultivated on contaminated sites. But for wheat uptake mechanisms are not entirely understood especially with regard to nutrient fertilization and different moisture regimes taking into account heavy rainfall events due to climate change. Here we show that especially higher P-fertilization under changing redox conditions may enhance arsenic uptake. This counteracts with higher N-fertilization reducing arsenic transfer and translocation into aboveground plant parts for both higher P-fertilization and reducing soil conditions. Arsenic speciation did not change in grain but for leaves P-fertilization together with reducing conditions increased the As(V) content compared to other arsenic species. Our results indicate important dependencies of nutrient fertilization, moisture conditions and substrate type on As accumulation of wheat as one of the most important crop plants worldwide with implications for agricultural practices.

We investigate the influence of the built-in voltage on the performance of organic bulk heterojuction solar cells that are based on a p-i-n structure. Electrical doping in the hole and the electron transport layer allows to tune their work function and hence to adjust the built-in voltage: Changing the doping concentration from 0.5 to 32 wt% induces a shift of the work function towards the transport levels and increases the built-in voltage. To determine the built-in voltage, we use electroabsorption spectroscopy which is based on an evaluation of the spectra caused by a change in absorption due to an electric field (Stark effect). For a model system with a bulk heterojunction of BF-DPB and C60, we show that higher doping concentrations in both the electron and the hole transport layer increase the built-in voltage, leading to an enhanced short circuit current and solar cell performance.

Background: Home visits are part of general practice work in Germany. Within the context of an expanding elderly population and a decreasing number of general practitioner (GPs), open questions regarding the organisation and adequacy of GPs’ care in immobile patients remain. To answer these questions, we will conduct a representative primary data collection concerning contents and organisation of GPs’ home visits in 2014. Because this study will require considerable efforts for documentation and thus substantial involvement by participating GPs, we conducted a pilot study to see whether such a study design was feasible. Methods: We used a mixed methods design with two study arms in a sample of teaching GPs of the University Halle. The quantitative arm evaluates participating GPs and documentation of home visits. The qualitative arm focuses on reasons for non-participation for GPs who declined to take part in the pilot study. Results: Our study confirms previously observed reasons for non-response of GPs in the particular setting of home visits including lack of time and/or interest. In contrast to previous findings, monetary incentives were not crucial for GPs participation. Several factors influenced the documentation rate of home visits and resulted in a discrepancy between the numbers of home visits documented versus those actually conducted. The most frequently reported problem was related to obtaining patient consent, especially when patients were unable to provide informed consent due to cognitive deficits. Conclusions: The results of our feasibility study provide evidence for improvement of the study design and study instruments to effectively conduct a documentation-intensive study of GPs doing home visits. Improvement of instructions and questionnaire regarding time variables and assessment of the need for home visits will be carried out to increase the reliability of future data. One particularly important methodological issue yet to be resolved is how to increase the representativeness of home visit care by including the homebound patient population that is unable to provide informed consent.

Safety has become one of the greatest gauging factors for organisational success, within the mining and construction industry of South Africa. This is due to the fact that organisations and their employees are expected to adhere to safety legislation, or risk permanent shutdown. Notwithstanding this importance, methods of communicating safety information to employees have not yet been widely researched – especially not within the unique context of the combined mining and construction industry of South Africa. In the light of the above, this study focused on researching those internal communication methods most suited for the communication of safety information. The systems theory as meta-theory, and the stakeholder relationship theory, the excellence theory and dual-capacity model were used to frame the study. An extensive literature review was firstly conducted, identifying and discussing internal communication methods, their use within the South African mining and construction industry, and specifically their application to safety communication. The concepts of communication satisfaction and communication effectiveness of internal safety communication, as well as employee relations were investigated. Secondly the application of these internal safety communication methods was then further researched empirically within the Gautrain project – specifically its Precast Yard –which is seated within both the mining, as well as the construction industry, as it has to adhere to safety legislations from both industries. This empirical research was done by means of questionnaires, focus groups, interviews, as well as a discussion of the communication channels employed by the organisation. This accounted for a triangulated approach of using quantitative, as well as qualitative methodologies. From this empirical research it was seen that the Precast Yard of the Gautrain project adheres to the guidelines set in the literature in some circumstances, whilst in others it does not. From these shortcomings, seven recommendations were formulated for the improvement of safety communication in this organisation. These include the proposal that safety communications should be strategically managed by integrating all forms of communication, so that external factors that may impact on this communication are factored in. Furthermore, the communication of safety information should strive to reflect the diverse viewpoints of the employees, as it endeavours to foster a relationship with them. Briefly, this study, therefore, focused on identifying and reporting on those methods and techniques suited for the internal communication of safety information, specifically within the South African mining and construction industry, thereby expanding the field. / Thesis (M.A. (Communication Studies))--North-West University, Potchefstroom Campus, 2010.

Safety has become one of the greatest gauging factors for organisational success, within the mining and construction industry of South Africa. This is due to the fact that organisations and their employees are expected to adhere to safety legislation, or risk permanent shutdown. Notwithstanding this importance, methods of communicating safety information to employees have not yet been widely researched – especially not within the unique context of the combined mining and construction industry of South Africa. In the light of the above, this study focused on researching those internal communication methods most suited for the communication of safety information. The systems theory as meta-theory, and the stakeholder relationship theory, the excellence theory and dual-capacity model were used to frame the study. An extensive literature review was firstly conducted, identifying and discussing internal communication methods, their use within the South African mining and construction industry, and specifically their application to safety communication. The concepts of communication satisfaction and communication effectiveness of internal safety communication, as well as employee relations were investigated. Secondly the application of these internal safety communication methods was then further researched empirically within the Gautrain project – specifically its Precast Yard –which is seated within both the mining, as well as the construction industry, as it has to adhere to safety legislations from both industries. This empirical research was done by means of questionnaires, focus groups, interviews, as well as a discussion of the communication channels employed by the organisation. This accounted for a triangulated approach of using quantitative, as well as qualitative methodologies. From this empirical research it was seen that the Precast Yard of the Gautrain project adheres to the guidelines set in the literature in some circumstances, whilst in others it does not. From these shortcomings, seven recommendations were formulated for the improvement of safety communication in this organisation. These include the proposal that safety communications should be strategically managed by integrating all forms of communication, so that external factors that may impact on this communication are factored in. Furthermore, the communication of safety information should strive to reflect the diverse viewpoints of the employees, as it endeavours to foster a relationship with them. Briefly, this study, therefore, focused on identifying and reporting on those methods and techniques suited for the internal communication of safety information, specifically within the South African mining and construction industry, thereby expanding the field. / Thesis (M.A. (Communication Studies))--North-West University, Potchefstroom Campus, 2010.

Background Ontologies play a major role in life sciences, enabling a number of applications, from new data integration to knowledge verification. SNOMED CT is a large medical ontology that is formally defined so that it ensures global consistency and support of complex reasoning tasks. Most biomedical ontologies and taxonomies on the other hand define concepts only textually, without the use of logic. Here, we investigate how to automatically generate formal concept definitions from textual ones. We develop a method that uses machine learning in combination with several types of lexical and semantic features and outputs formal definitions that follow the structure of SNOMED CT concept definitions. Results We evaluate our method on three benchmarks and test both the underlying relation extraction component as well as the overall quality of output concept definitions. In addition, we provide an analysis on the following aspects: (1) How do definitions mined from the Web and literature differ from the ones mined from manually created definitions, e.g., MeSH? (2) How do different feature representations, e.g., the restrictions of relations’ domain and range, impact on the generated definition quality?, (3) How do different machine learning algorithms compare to each other for the task of formal definition generation?, and, (4) What is the influence of the learning data size to the task? We discuss all of these settings in detail and show that the suggested approach can achieve success rates of over 90%. In addition, the results show that the choice of corpora, lexical features, learning algorithm and data size do not impact the performance as strongly as semantic types do. Semantic types limit the domain and range of a predicted relation, and as long as relations’ domain and range pairs do not overlap, this information is most valuable in formalizing textual definitions. Conclusions The analysis presented in this manuscript implies that automated methods can provide a valuable contribution to the formalization of biomedical knowledge, thus paving the way for future applications that go beyond retrieval and into complex reasoning. The method is implemented and accessible to the public from: https://github.com/alifahsyamsiyah/learningDL.

Iron and manganese are relevant constituents of the earth's crust and both show increasing mobility when reduced by free electrons. This reduction is known to be controlled by microbial dissimilation processes. Alternative sources of free electrons in nature are cloud-to-ground lightning events with thermal and galvanic effects. Where thermal effects of lightning events are well described, less is known about the impact of galvanic lightning effects on metal mobilization. Here we show that a significant mobilization of manganese occurs due to galvanic effects of both positive and negative lightning, where iron seems to be unaffected with manganese being abundant in oxic forms in soils/sediments. A mean of 0.025 mmol manganese (negative lightning) or 0.08 mmol manganese (positive lightning) mobilization may occur. We suggest that lightning possibly influences biogeochemical cycles of redox sensitive elements in continental parts of the tropics/subtropics on a regional/local scale.