10,037 research outputs found

    Fokus auf der Untersuchung des Einflusses biometrischer Faktoren auf das Ergebnis der nTMS Messung sprachrelevanter Areale neurochirurgischer Patienten

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    Objective: Navigated transcranial magnetic stimulation (nTMS) is a non-invasive mapping tool to locate functional areas of the brain, gaining importance as a preoperative diagnostic device. This is a summary of three studies, Schwarzer et al., Rosenstock et al. and Zdunczyk et al., whose aim it is to increase the accuracy and usability of nTMS in different neurosurgical patient groups. They intend to describe neurophysiological data gained through nTMS as a supportive measure for surgical planning to increase patient safety and improve outcome. Methods: All patients and healthy subjects were examined via bihemispheric nTMS. Schwarzer et al. ascertained a baseline picture naming performance and used repetitive nTMS (rnTMS) to induce speech disruptions to identify individual language areas in patients with language eloquent lesions. Nine biometric factors were analyzed for correlation with elevated error occurrence. Rosenstock et al. concentrated on the primary motor cortex of patients with motor-eloquent glioma and performed correlation analyses to test the association of nTMS-related variables and postoperative motor outcome. Zdunczyk et al. examined patients with degenerative cervical myelopathy (DCM) and healthy volunteers to see differences in neurophysiological nTMS data due to disease severity. Results: Schwarzer et al. showed a significant increase in error occurrence with increased severity of cognitive impairment (p8mm (p=0.014). New postoperative deficits could be seen in patients with pathological excitability of the motor cortex (resting motor threshold ratio 110%, p=0.031). Patients with DCM had a reduced corticospinal excitability estimated by the recruitment curve (p=0.022), and patients with mild symptoms showed an increased activation on non- primary motor areas (p<0.005). Patients with severe symptoms showed a higher cortical inhibition (p<0.05) and a reduced motor area (p<0.05). Conclusion: Most patients are eligible for rnTMS language mapping. A new protocol for language mapping is proposed for secure identification of patients eligible for reliable rnTMS in Schwarzer et al. Rosenstock et al. introduce a new risk stratification model, based on objective functional-anatomical and neurophysiological measures, which enables physicians to counsel patients about the risk of functional deterioration or the potential for recovery and supports surgical planning. Zdunczyk et al. propose a new concept for functional compensation for DCM on the cortical and spinal level: the corticospinal reserve capacity. nTMS is a viable diagnostic tool to characterize this and its parameters serve as valuable prognostic factors.Fragestellung: Navigierte transkranielle Magnetstimulation (nTMS) ist eine nicht-invasive Untersuchungsmethode, um kortikale Funktionsareale zu identifizieren, welche zunehmend an Bedeutung als präoperatives diagnostisches Mittel gewinnt. Dies ist eine Zusammenfassung dreier Studien, Schwarzer et al., Rosenstock et al. und Zdunczyk et al. Die Studien haben als Ziel, die Benutzerfreundlichkeit und Genauigkeit von nTMS für unterschiedliche neurochirurgische Patientengruppen zu verbessern. Neurophysiologische Parameter wurden mittels nTMS erhoben, um die operative Planung zu unterstützen und das individuelle Patientenrisiko korrekt einzuschätzen und zu verbessern. Methodik: Alle Patienten und Probanden wurden bihemisphärisch mittels nTMS untersucht. Schwarzer et al. erhoben vorher die individuelle Fähigkeit zur Objektbenennung (baseline) und nutzten repetitive nTMS (rnTMS), um Sprachunterbrechungen hervorzurufen und somit Kortexareale bei Patienten mit sprachrelevanten Hirnläsionen zu identifizieren. Neun biometrische Patienteneigenschaften wurden in ein Verhältnis mit der Fehleranfälligkeit gesetzt. Rosenstock et al. untersuchten den primär motorischen Kortex bei Gliompatienten und analysierten den Zusammenhang von nTMS-ermittelten Parametern mit dem postoperativen Patientenzustand. Zdunczyk et al. betrachteten Patienten mit degenerativer zervikaler Myelopathie (DCM), sowie gesunde Probanden und ermittelten die unterschiedlichen nTMS-Parameter in Abhängigkeit von der Symptomschwere. Ergebnisse: Die meisten biometrischen Faktoren zeigten keinen statistischen Zusammenhang mit dem Stimulationsergebnis bei Schwarzer et al. Je schwerer der Aphasiegrad und die kognitiven Einschränkungen waren, desto mehr Sprachfehler wurden in der rnTMS Untersuchung gemacht (je p8mm zwischen Tumor und kortikospinalem Trakt keine neuen permanenten postoperativen Defizite auftraten (p=0.014). Neue postoperative Defizite traten bei Patienten mit präoperativ pathologischer Kortexerregbarkeit (Ruhemotorschwellenverhältnis RMT 110%, p=0.031) auf. DCM Patienten wiesen eine reduzierte kortikospinale Erregbarkeit, gekennzeichnet durch ein Abflachen der recruitment curve, auf (p=0.022). Ein vergrößertes motorisch relevantes Kortexareal mit Aktivierung sekundärer Motorareale zeigte sich bei Patienten mit milder Symptomatik (p<0.005), während bei schwer betroffenen Patienten eine erhöhte kortikale Hemmung (CSP, p<0.05) und reduzierte motorische Kortexfläche auffiel (p<0.05). Schlussfolgerung: Schwarzer et al. stellen ein neues Prüfungsprotokoll für die Eignung von Patienten für ein reliables rnTMS Ergebnis vor, wobei die statistische Analyse ergab, dass die meisten Patienten für eine reliable rnTMS Sprachuntersuchung geeignet sind. Rosenstock et al. präsentieren ein neues Risikostratifikationsmodell für Patienten mit motorisch relevanten Gliomen, wodurch der Operateur anhand von funktionell-anatomischen und neurophysiologischen Parametern das individuelle Patientenrisiko für den postoperativen Verlauf einschätzen kann. Zdunczyk et al. beschreiben einen möglichen funktionellen Kompensationsmechanismus bei DCM Patienten auf kortikaler und spinaler Ebene: die kortikospinale Reservekapazität. Die durch nTMS ermittelten Parameter lassen damit objektivierbare prognostische Aussagen zu

    Changes in glass consumption in Pergamon (Turkey) from Hellenistic to late Byzantine and Islamic times

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    We present compositional data for nearly 100 glass samples from Pergamon, western Turkey, spanning 1500 years from the Hellenistic to Late Byzantine and Islamic periods. The data shows the use of already-known Roman glass groups during the first half of the time frame, for imported vessels as well as locally worked glass. No compositional change is seen related to the introduction of glass blowing for either of the glass groups in use during this time. During the first half of the 1st millennium AD, two previously little-known boron- and alumina-rich compositional groups emerge. These glass groups, thought to be regionally produced, dominate glass compositions in Pergamon during the mid-to late Byzantine and Islamic periods, indicating a major shift in glass supply and a fragmentation of the economy into more regional units. Plant-ash glass, from the 9th century AD replacing mineral natron glass in the Levant, plays only a minor role in Byzantine and Islamic Pergamon

    FOODLIT-PRO: Food literacy domains, influential factors and determinants—A qualitative study

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    Poor eating habits are increasing the prevalence of weight-related issues, such as diabetes and cardiovascular diseases. Given the demand to improve individuals’ food knowledge and competencies aiming at healthier behaviours, the current investigation explores the concept of food literacy. Considering the lack of a shared understanding of food literacy, this study aims to explore food literacy’s domains, influential factors and determinants. Using a qualitative deductive-dominant content analysis, 30 experts from food-related fields were interviewed. The obtained outcomes were compared to available food literacy frameworks. Agreement among inter-raters was nearly perfect (k = 0.82). Yielding a total of 184 codes nested within 19 categories, identified domains were Origin, Safety, Choice and Decision, Select and Acquire, Plan, Preserve, Prepare, Cook, and Knowledge; influential factors included Nutrition, Psychological, Health, Learning Contexts, Policy, Industry, Sustainability, and Social and Cultural; External determinants were “Access to Food-Related Information”, “Perishable and/or Unreliable Food-Related Information”, “Family Dynamic and/or Identity”, and “Professionals’ Unpreparedness on Food-Related Expertise”, and Internal determinants included “Prioritise Food”, “Convenience and Practicality”, “Time and Financial Management”, “Previous Food-Related Habits”, and “Innate and Learned Flavour Preferences”. In conclusion, more than half of the identified attributes (62.5%) are corroborated by the current literature. However, the manifested content unmatched with the current frameworks of food literacy literature express food-literacy-related fields of action, knowledge, competencies, and determinants that have not yet been explored. As such, this study provides new and useful information concerning food literacy definition and development, by identifying its domains, factors of influence, and potential determinants. Moreover, this work paves the way for new measurements and interventions within this field

    Qualitative failure analysis on laminate structures of windsurfing boards using analytical linear elastic modelling

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    Recently developed mathematical tools for the modelling of contact problems on thin film structures are adapted to allow the investigation of arbitrarily mixed purely isotropic and transversally isotropic laminate structures. The new tool is applied to model a variety of load problems resulting in the failure of windsurfing boards consisting of a relatively thin laminate shell and a soft polymer foam core. It is shown that local impact and distributed bending loads due to “bad landing” after high jumps or contact with parts of the sailing gear (the so called rig) especially the front part of the boom are leading to the most critical stress distributions resulting in failure. So most of the investigated boards were damaged because the rider (windsurfer) landed flat and thus produced a sudden impact force under his feet (impact defect). Other overloading occurred due to overturning of so called loop movements or the landing of the board exactly on respectively between two waves and this way producing high bending moments. Some of those typical loads are analysed in detail and the stresses occurring in the complex structure of the windsurfing boards are evaluated

    Piscinas biológicas e serviços ecossistémicos: que relação?

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    Os ecossistemas oferecem à humanidade uma vasta gama de benefícios denominados serviços ecossistémicos, englobando a purificação da água e estímulos estéticos e espirituais. Estes serviços estão em larga medida dependentes da conservação da biodiversidade. As piscinas convencionais contribuem para a degradação destes serviços, pois a depuração da água exige para além do cloro, outros produtos para ajuste do pH e algicidas, tóxicos para um grande número de espécies. Por outro lado, as piscinas biológicas são lagos construídos que imitam e recriam os processos ecológicos que ocorrem nos sistemas naturais, constituindo uma solução de engenharia natural, que permite criar espaços de lazer aquáticos de baixo impacto ambiental. Nestes sistemas, a purificação da água, com o objetivo de ter qualidade para fins balneares, é realizada por filtros biológicos e plantas aquáticas (utilização dos serviços ecossistémicos). Como não é adicionado nenhum produto químico à água estes sistemas são rapidamente colonizados por plâncton, macroinvertebrados e alguns vertebrados, promovendo a manutenção da biodiversidade e o aumento do valor estético da envolvente (conservação e recuperação dos serviços ecossistémicos). As piscinas biológicas também funcionam, à escala da paisagem, como habitats que facilitam os fluxos de algumas espécies entre diferentes cursos de água e como reservatórios de água.info:eu-repo/semantics/publishedVersio

    Implications of macrophyte abundance on algal growth management: The case of three natural swimming pools with distinct macrophyte abundance

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    Natural swimming pools are small constructed lakes for recreational proposes. They are composed by a swimming area merging with an area planted with emergent and submerged macrophytes, which function as biological filters. Fish are absent, however a wide diversity of phytoplankton, zooplankton and macroinvertebrate species colonize these pools. Therefore, pools can be regarded as the ideal systems to extrapolate the implications of macrophyte abundance management on algal growth control. The present study was taken in three pools (A, B and C) located in Minho Region (Northern Portugal) In early summer the macrophyte area had a 30% of cover in Pool A, in B 40% and in C 60%. Phytoplankton, zooplankton and filamentous algae abundance as well as conductivity, pH, dissolved oxygen, hardness, nitrates, nitrites, ammonia, phosphates were recorded in February, April and June. The lowest densities of phytoplankton were observed in pool C. Besides, filamentous algae were abundant in the pool A, whereas in B and C they were recorded only in summer. In Pool A, zooplankton assemblage was always dominated specialists on small particle feeding, which food preference are detritus and bacteria. Conversely, in the Pool C herbivorous zooplankton was predominant. The low algal densities observed in the Pool C are explained by the presence of a well established macrophyte assemblage. These plants contribute to the reduction of algal densities by (1) creating of areas of shade; (2) removing nutrients from water column and (3) provide refuges for herbivorous zooplankton. Therefore, the present study stresses the pertinence of take in account the key role of aquatic macrophytes when management practices for algal growth control are developed

    Short note on improved integration of mechanical testing in predictive wear models

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    In this work, a new global increment nano-fretting wear model based on the effective indenter concept has been used and the results were compared with experimental data. A series of DLC coatings with varied mechanical properties was deposited using industrial scale PECVD system and characterised on a low-drift nanomechanical test platform (NanoTest Vantage). 4500. cycle nano-scale fretting measurements have been performed in order to examine the tribological properties of the coatings. A physical analysis of the nanoindentation test enabled the true coating Young's Modulus (E) and the coating yield strength (Y) to be determined. In comparison to the hardness (H) this is the basis for a more generic understanding of the mechanical coating behaviour. This allowed a direct examination of the influence of the variation of Y/. E in the coatings on the observed nano-fretting wear, with the coating with highest Y/. E showing significantly improved resistance to nano-fretting wear. A preliminary evaluation of the stress field evolution during the test and the extraction of wear and fretting parameters provides the opportunity to discuss the effects possibly being dominant within the nano-scale tribo-tests

    The EU’s incremental adjustments to the eurocrisis may not be enough to meet the coming challenges to its governance and democratic legitimacy.

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    Since the beginning of the eurozone debt crisis three years ago, the member states have been forced to change the governance of the eurozone in a long period of crisis management. Daniela Schwarzer looks over the major changes to the EU’s governance structure, arguing that the European Council, Germany, and the European Central Bank have moved to the centre stage, often leading to the marginalization of other supranational actors and smaller member states in decision making. She argues that while the eurozone has shown a remarkable capacity to adjust thus far, it may need far more fundamental reform to its institutional set-up if it is to cope with looming problems of governance and legitimacy
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