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Plasma-based accelerators are on the brink of a development stage, where applications of the beam for medical sciences, imaging, or as an injector for a future large-scale accelerator-driven light source become feasible. The requirements on electron beams for injection into a storage-ring are stringent regarding beam quality and reliability. Here, we propose a beam diagnostic technique for measuring lateral beam sizes with a few-μm resolution by applying a state-of-art single-photon camera to coherent synchrotron radiation that affords by a sub-femtosecond short bunch-length property. A sophisticated image processing algorithm enables the technique down to 5 photons/pixel for the visibility of 0.132. Results show the potential of the proposed system that achieves precise retrieval of the complex degree of coherence at an extremely low photon intensity similar to those expected towards the plasma-acceleration injectors. Before laser-driven accelerators can reach broad application, their performance must be ensured by robust characterization. Here, an interferometric method allowing high-resolution measurement of the beam size is demonstrated.

Zusammenfassung Hintergrund Kenntnisse über den typischen Ausspracheerwerb sind notwendig, um Aussprachestörungen identifizieren zu können. Hierbei spielt die phonologische Prozessanalyse eine wichtige Rolle. Informationen zum Ausspracheerwerb bilingualer Kinder sind bislang rar, sodass eine Diagnosestellung erschwert ist. Methode Mit Hilfe eines Bilderbenenntests wurden die phonologischen Prozesse im Deutschen von 84 türkisch-deutsch bilingualen Kindern im Alter von 3;0–5;5 Jahren untersucht. Ergebnis Bis auf wenige Ausnahmen (z. B. Vokalfehler) wurden nur phonologische Prozesse im Deutschen beobachtet, die denen monolingualer Kinder entsprechen. Diese wurden meist später als von monolingualen Kindern überwunden. Simultan und sukzessiv bilingual aufwachsende Kinder unterschieden sich hier kaum. Diskussion Die Ergebnisse bestätigen bisherige Pilotstudien zum türkisch-deutschen Phonologieerwerb und können zur Orientierung in der sprachtherapeutischen Aussprachediagnostik herangezogen werden.

International audience; The stinging nettle Urtica dioica L. is a perennial crop with low fertilizer and pesticide requirements, well adapted to a wide range of environmental conditions. It has been successfully grown in most European climatic zones while also promoting local flora and fauna diversity. The cultivation of nettle could help meet the strong increase in demand for raw materials based on plant fibers as a substitute for artificial fibers in sectors as diverse as the textile and automotive industries. In the present review, we present a historical perspective of selection, harvest, and fiber processing features where the state of the art of nettle varietal selection is detailed. A synthesis of the general knowledge about its biology, adaptability, and genetics constituents, highlighting gaps in our current knowledge on interactions with other organisms, is provided. We further addressed cultivation and processing features, putting a special emphasis on harvesting systems and fiber extraction processes to improve fiber yield and quality. Various uses in industrial processes and notably for the restoration of marginal lands and avenues of future research on this high-value multi-use plant for the global fiber market are described.

In commercial injection moulding simulation software only tools for glass fibre-reinforced thermoplastics exist, but not for natural fibres. In our research, we adapted a simulation software for sisal fibre-reinforced polypropylene. To evaluate our simulation results, three experimental methods, to measure fibre orientation are compared to each other using injection moulded sisal fibre-reinforced polymer parts: terahertz spectroscopy, μ-CT and light microscopy measurements (LMM) of microtome sections. Terahertz spectroscopy determines the main orientation over the plate thickness, but it neglects variances of fibre orientation across the plate thickness. Using μ-CT and LMM allows measuring fibre orientation at different layers across the plate thickness and to detect a shell-core effect. Care has to be taken comparing results from μ-CT and LMM, due to their differences in the slice thicknesses. The orientation found with the μ-CT correlates well with the injection moulding simulation developed for sisal fibre-reinforced polypropylene.

With the help of new design tools, manufacturing-integrated solutions can be generated that concurrently consider function and process. Based on the design pattern matrix, solution elements can be developed that realize the product function by systematically utilizing manufacturing-induced properties. The developed manufacturing-integrated product solutions are refined using computer-aided methods (feature-based modeling and information modeling). A product embodiment is generated that is specifically tailored to the chosen manufacturing technology. An integrated information model allows the introduced tools to be used throughout the entire development process. The example of a linear flow split snap-fit fastening illustrates how the tools beneficially interact and realize manufacturing potential, resulting in an innovative product design.

The present study focuses on the reprocessing behaviour of recycled injection moulded polylactide (PLA) composites. The composites are reinforced with regenerated cellulose fibres (lyocell) of variable fineness and a fibre mass content of 30%. They were reprocessed up to three times. The influence of reprocessing on the fibre length distribution and the resulting composite mechanical properties (tensile and impact strength) was analysed. While the first reprocessing cycle does not affect the mechanical characteristics of the neat PLA matrix, the strength of the composites decreases significantly due to a decreasing fibre aspect ratio. It was shown that fibres having a larger cross-sectional area display a lower aspect ratio than finer fibres, after reprocessing. This phenomenon leads to a larger decrease in tensile strength of composites reinforced with coarser fibres when compared to composites reinforced with finer fibres. A comparison of virgin composites and threefold reprocessed composites with a similar fibre length distribution resulted in a significantly higher tensile strength compared to the virgin sample. This result leads to the conclusion that not only the fibre length is drastically reduced by reprocessing but also that the fibres and the matrix were damaged.

The Multihemp biorefinery concept combines processing systems that, starting from harvesting, transform hemp biomass into a spectrum of marketable intermediate and final products. Hackling loss sorted out during production of long hemp was used for the compounding process to produce hemp fibre-reinforced Polylactide (PLA) granules for the injection moulding process. Even though only side stream fibres were used, the overall mechanical properties lie within the range of properties reported for PLA – bast fibre composites cited in the literature or even above. The use of hemp from an earlier harvest at full flowering (harvest 1) significantly increases Young’s modulus values compared to the pure PLA polymer and shows a slightly better reinforcing potential than hemp harvested later at seed maturity (harvest 2). A significant influence of harvest time on the composite properties was found, which is stronger than the variety influence. Based on the presented results, the poly-product MultiHemp system showed a proof of concept for the use of hackling loss for injection moulded composites.

To establish injection-moulded, natural fibre-reinforced polymers in the automotive industry, numerical simulations are important. To include the breakage behaviour of natural fibres in simulations, a profound understanding is necessary. In this study, the length and width reduction of flax and sisal fibre bundles were analysed experimentally during compounding and injection moulding. Further an optical analysis of the fibre breakage behaviour was performed via scanning electron microscopy and during fibre tensile testing with an ultra-high-speed camera. The fibre breakage of flax and sisal during injection moulding was modelled using a micromechanical model. The experimental and simulative results consistently show that during injection moulding the fibre length is not reduced further; the fibre length was already significantly reduced during compounding. For the mechanical properties of a fibre-reinforced composite it is important to overachieve the critical fibre length in the injection moulded component. The micromechanical model could be used to predict the necessary fibre length in the granules.

Unter evidenzbasiertem Handeln im klinischen Alltag wird meist verstanden, die bestmogliche therapeutische Versorgung eines Patienten zu gewahrleisten. Dies setzt allerdings voraus, dass es zunachst moglich ist, ein behandlungsbedurftiges Problem verlasslich zu ermitteln. Dollaghan (2007) beschreibt die Bedeutung der Qualitat von Messverfahren fur die interne Validitat empirischer Evidenz. Es stellt sich die Frage, ob die Qualitat diagnostischer Verfahren in den Therapieberufen in Deutschland ausreichend ist, um evidenzbasierte Praxis anzuwenden. Daher werden Merkmale zur Uberprufung der Validitat und Reliabilitat von Diagnostikinstrumenten vorgestellt und fur ein Teilgebiet der Logopadie (kindliche Aussprachestorungen) praktisch angewandt. Es zeigt sich, dass im deutschsprachigen Raum bislang kaum eine Diskussion dieses Themas zu finden ist und dass die existierenden Verfahren fur den untersuchten Bereich nicht oder nur bedingt den Qualitatsanspruchen genugen.

Virtual product development aims at the use of information modeling techniques and computer-aided (CAx-) tools during the product development process, to represent the real product digitally as an integrated product model (Anderl and Trippner 2000). Thereby, data related to the product as well as product properties are generated and stored as result of the product development process (e.g., product planning, conceptual design) (Pahl et al. 2007; VDI 2221 1993). Within virtual product development CAx process chains have been established. They comprise the concatenating of the applied tools and technologies within the steps of the virtual product development process enabling the consistent use of product data (Anderl and Trippner 2000). The computer-aided design (CAD) technology aims at the integration of computer systems to support engineers during the design process such as design conceptualization, design, and documentation. It provides the geometry of the design and its properties (e.g., mass properties, tolerances) which is abstracted to be used in computer-aided engineering (CAE) systems (e.g., finite element method (FEM)) for design analysis, evaluation, and optimization. The computer-aided process planning (CAPP) technology provides tools to support process planning, Numerical Control (NC) programming, and quality control (Hehenberger 2011; Lee 1998; Vajna 2009). The advantages are continuous processing and refinement of the product model, minimizing the modeling efforts regarding time as well as costs and avoiding error sources. In addition, all relevant data and information related to the product can be provided for subsequent processing (Anderl and Trippner 2000). CAx technologies have been widely established within the product development processes in industry. They have been further developed in the last years; however efforts to integrate and to automate them are still a topic of research. Especially, with the introduction of innovative manufacturing technologies such as linear flow and bend splitting require new methods and tools for the virtual product development process. These technologies enable the production of a new range of sheet metal products with characteristic properties (e.g., Y-profile geometry, material properties) that are not addressed in state-of-the-art methods and tools.

One of the key challenges faced by engineers is finding, concretizing, and optimizing solutions for a specific technical problem in the context of requirements and constraints (Pahl et al. 2007). Depending on the technical problem’s nature, specifically designed products and processes can be its solution with product and processes depending on each other. Although products are usually modeled within the context of their function, consideration of the product’s life cycle processes is also essential for design. Processes of the product’s life cycle concern realization of the product (e.g., manufacturing processes), processes that are realized with the help of the product itself (e.g., use processes) and processes at the end of the product’s life cycle (recycling or disposal). Yet, not just product requirements have to be considered during product development, as requirements regarding product life cycle processes need to be taken into account, too. Provision for manufacturing process requirements plays an important role in realizing the product’s manufacturability, quality, costs, and availability (Chap. 3). Further life cycle demands, such as reliability, durability, robustness, and safety, result in additional product and life cycle process requirements. Consequently, the engineer’s task of finding optimal product and process solutions to solve a technical problem or to fulfill a customer need is characterized by high complexity, which has to be handled appropriately (Chaps. 5 and 6).

Within the Collaborative Research Center 666 the algorithm based product development process has been established. It is based on state of the art product development methodologies and enhanced in order to optimize the product development process of integral bifurcated sheet metal parts. Algorithms based on mathematical optimization approaches as well as the initial product requirements and constraints information are applied to obtain an optimized design as CAD-Model. Regarding this methodology there are still some challenges to be solved, such as reduction of iterations steps to elaborate final product design as CAD-model, use of heterogeneous data as well as software and enhancement of information exchange. Therefore, this paper introduces a concept for a web-based application to support the algorithmic product development methodology and CAD modeling in CRC 666. It enables the development and adaptation of integral bifurcated parts based on the initial optimization data provided by XML-files. Besides the description of use cases and use scenarios, the concept is implemented as a web-based application for validation purposes. Based on the validation, advantages and limitations of the presented approach are discussed.

The present study investigates the influence of different plasma treatments on the tensile characteristics of lyocell fibers and the interfacial interactions of lyocell fibers in a poly(lactic acid) matrix. For the investigations, the fibers were coated by an amine-functional, nanoporous layer (a-C:H:N) using a gaseous mixture of NH3:C2H4 of 1:1 and 5:3, respectively, an oxygen-functional layer (a-C:H:O) with CO2:C2H4 and CO2 posttreatment, or an oxygen-functional layer (a-C:H:O) comprising hydroxyl groups with H2O:C2H4 and H2O posttreatment. As reference, uncoated fibers and fibers coated with a crosslinked, amorphous hydrocarbon layer (a-C:H) without functional group incorporation were investigated. While the different treatments maintained the tensile strength of the lyocell fibers, which were all in the range between 295 and 338 N/mm2, the interfacial shear strength, measured by the pull-out test, was clearly influenced. The best improvement of the fiber/matrix adhesion was obtained by a plasma treatment with a mixture of water vapor and ethylene resulting in an interfacial shear strength of 17.8 N/mm2 in comparison to the untreated lyocell fiber with 10.3 N/mm2. Amine-functional plasma polymers (a-C:H:N) were also found to be suitable for adhesion-promoting interlayers on lyocell fibers in poly(lactic acid). © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

The aim of the present study was to assess the effects of vaccination against boar taint on testosterone levels, body weight and behaviour in male fattening pigs when compared with boars and barrows. The study was carried out in two replicates over time. Pigs were allocated to fattening pens according to treatment group (immunised males (IM), castrated males (CM), entire males (EM)) with 10 and 13 pigs per pen in batches one and two, respectively. IM pigs were vaccinated twice with Improvac™ according to manufacturer's instructions (first injection was given on the day of entry to the fattening unit, second injection was performed when pigs had an average weight of 76.6 kg and 80.4 kg in the two replicates over time, respectively). During fattening, pigs were videotaped twice (test periods one and two) for a consecutive period of 96 h during each test period and blood samples were taken. Live weight measurements were conducted on a weekly basis. Before second vaccination was given (test period one), IM pigs had serum testosterone levels comparable to those of entire boars. Two weeks after second Improvac™-injection (test period two) testosterone levels of IM pigs decreased significantly ( p p p

The Collaborative Research Centre 666 has the focus on researching fundamental new methods for the development of optimized products and production processes for integral bifurcated sheet metal parts. Technological innovations have been achieved with respect to new production processes such as linear flow splitting and linear bend splitting as well as to produce products with flexible profiles. The use of state of art product development methodologies can be applied but these are not optimized to deal with the high complexity of the requirements and properties of integral bifurcated sheet metal products. In order to deal with that complexity a new approach of a product development methodology, the algorithm based product development process, has been established. Within the scope of the algorithm based product development methodology a topology optimization, based on mathematical algorithms using product requirements information, is already applied in the conceptual steps of product development process. By using this methodological approach an optimized concept of bifurcated sheet metal can be determined. The results are stored as optimized geometric data in XML-format files. 3D-CAD-Models are generated based on these data. However the import of these data into 3D-CAD-Systems are not fully automated. The developed data model, from earlier works for linear flow splitting and linear bend splitting, does not take into account the variability of the profiles in the third-dimension. In addition the topology optimization does not provide production-orientated design requirements and therefore it does not take into account the production process limits (of linear flow splitting and linear bend splitting). Hence 3D-CAD-Models resulting from the optimized geometric data need to be adapted manually. Therefore new advanced approaches in terms of virtual product development tools need to be explored. This paper describes the development of an interface within the CAD-System Siemens NX which supports the automatic import of XML-files containing the optimized geometric data of non-linear integral bifurcated sheet metal in 3D-CAD-Models. The existing data model is extended considering the requirements of the developed interface in order to represent nonlinear bifurcated profiles. An approach of the interface using the described data model and the NX Open API is introduced and explained.

Todays’ product development process is characterized by an increasing use of embedded software solutions integrated into mechatronic products. The development is more and more translocated into a virtual environment. New software methods and tools have to be developed. Industry 4.0 is an approach to highlight the tendency of modern development. Communication between smart products, communication via internet technologies, cyber-physical systems and the Internet of Things are the basis of Industry 4.0. Owing this development, used project management methodologies have to be adjusted. In special the well-known V-Model is now extended to the W-Model to cope with the new requirements like communications between different disciplines. New approaches in virtual development have to be adapted to modern teaching techniques. Therefore a course for first semester mechanical engineering students is conducted by the department of Computer Integrated Design at the Technische Universität Darmstadt. Industry 4.0 fundamentals are taught as well as the development process underlying the so called W-Model. The students will apply this knowledge while they participate in exercises. A web-based tutorial is provided every week with different learning packages. With these learning packages, the students learn to use the project management techniques as well as software development techniques to solve different tasks. Later complex data structures and algorithms can be coded and are applied. The software development techniques, established in development of information technologies, gets more important in mechanical engineering. Therefore the students learn these aspects. Over three months length the students work in groups and use all their skills to realize a bigger software-project — a digital factory. They use a virtual testing environment (ViTMeS 3.0) to develop their solution. The presented ViTMeS 3.0 is a further development of a virtual testing environment used in last year’s team work. Later they can test their code with a real life example. This example, the digital factory, built with LEGO Mindstorms, is an important part of teaching students the foundations of communication and information techniques as well as software development and programming skills. The last step of the team work is the coding of a graphical user interface for appropriate visualization.

Smart Engineering aims at a new approach for describing, designing and dimensioning Smart Products. Design methodology is far advanced and provides both a systematic approach to develop new products as well as appropriate methods to support development tasks in specific development phases. Within this development process the communication capabilities of Smart Products, the structure of communication among Smart Products as well as executing functional operations triggered by communicated messages is not described yet.

In Europe growing concerns regarding animal welfare issues in pig production have forced the pig industry to introduce alternative methods to conventional castration procedures. Besides the raising of entire males and castration in combination with analgesia and anaesthesia the vaccination against GnRF (Gonadotropin-releasing factor) seems to be the most promising long-term solution. Immunised male pigs (IM) show higher average daily weight gain than surgically castrated males (CM). Additionally the feed intake in IM is lower than in CM and feed conversion ratio is consequently better. Carcass weight, back fat depth and dressing percentage of IM pigs are intermediate between CM and entire males while meat quality seems not to be influenced by castration technique since CM and IM show comparable results. Steroid hormone concentrations in IM decline to very low levels (below detection line) after the second administration of the anti-GnRF vaccine and boar taint compounds are reliably metabolized. Pigs which received two injections of the anti-GnRF vaccine reduce their sexual and aggressive behaviour to levels of CM pigs which results in low incidents of injury and carcass damages. Surveys analyzing the consumers’ attitude to vaccination against boar taint reveal that if profound information on the technique is provided, the acceptance of meat from vaccinated animals is even better than the acceptance of meat from pigs castrated under current farm conditions. Furthermore economic analyses reveal that immunisation against GnRF provides a potential for a return on investment since better feed efficiency compensates for the additional costs of drug and labour time.

The role of glucocorticoids in the regulation of apoptosis remains incongruous. Here, we demonstrate that corticosterone protects neurons from apoptosis by a mechanism involving the cyclin-dependent kinase inhibitor p21Waf1/Cip1. In primary cortical neurons, corticosterone leads to a dose- and Akt-kinase-dependent upregulation with enhanced phosphorylation and cytoplasmic appearance of p21Waf1/Cip1at Thr 145. Exposure of neurons to the neurotoxin ethylcholine aziridinium (AF64A) results in activation of caspase-3 and a dramatic loss of p21Waf1/Cip1preceding apoptosis in neurons. These effects of AF64A are reversed by pretreatment with corticosterone. Corticosterone-mediated upregulation of p21Waf1/Cip1and neuroprotection are completely abolished by glucocorticoid and mineralocorticoid receptor antagonists as well as inhibitors of PI3- and Akt-kinase. Both germline and somatically induced p21Waf1/Cip1deficiency abrogate the neuroprotection by corticosterone, whereas overexpression of p21Waf1/Cip1suffices to protect neurons from apoptosis. We identify p21Waf1/Cip1as a novel antiapoptotic factor for postmitotic neurons and implicate p21Waf1/Cip1as the molecular target of neuroprotection by high-dose glucocorticoids.

Following the algorithm based product development process, integral bifurcated sheet metal profiles are optimized. However mathematical optimized profiles do not contain information about manufacturing restrictions or additional information. Therefore many iterations between product development and manufacturing are necessary until the production of the profile. The following contribution introduces manufacturing restriction models and their integration as non-geometric information into mathematical optimized profiles to reduce the time costing iterations for adapting a profile.