468 research outputs found

    Orientation and temperature dependence of some mechanical properties of the single-crystal nickel-base superalloy Rene N4. 3: Tension-compression anisotropy

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    Single crystal superalloy specimens with various crystallographic directions along their axes were tested in compression at room temperature, 650, 760, 870, and 980 deg C. These results are compared with the tensile behavior studied previously. The alloy, Rene N4, was developed for gas turbine engine blades and has the nominal composition 3.7 Al, 4.2 Ti, 4 Ta, 0.5 Nb, 6 W, 1.5 Mo 9 Cr. 7.5 Co, balance Ni, in weight percent. Slip trace analysis showed that primary cube slip occurred even at room temperature for the 111 specimens. With increasing test temperature more orientations exhibited primary cube slip, until at 870 deg C only the 100 and 011 specimens exhibited normal octahedral slip. The yield strength for octahedral slip was numerically analysed using a model proposed by Lall, Chin, and Pope to explain deviations from Schmid's Law in the yielding behavior of a single phase Gamma prime alloy, Ni3(Al, Nb). The Schmid's Law deviations in Rene N4 were found to be largely due to a tension-compression anisotropy. A second effect, which increases trength for orientations away from 001, was found to be small in Rene N4. Analysis of recently published data on the single crystal superalloy PWA 1480 yielded the same result

    Placebos in der Psychotherapieforschung – eine systematische Analyse am Beispiel der systematischen Desensibilisierung

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    Hintergrund: Die Voraussetzungen der randomisierten, Placebo-kontrollierten Evaluation - die Ununterscheidbarkeit der Therapiebedingungen fĂŒr die Patienten und die Verblindung der Therapeuten - sind in der Psychotherapieforschung nicht uneingeschrĂ€nkt gegeben. Das Ziel dieser qualitativen systematischen Übersichtsarbeit ist es, am Beispiel der systematischen Desensibilisierung (SD) die Vorgehensweisen zur Bestimmung der BehandlungsspezifitĂ€t zu beschreiben und deren theoretische und praktische Implikationen zu diskutieren. Methodik: Auf der Basis einer systematischen Literaturrecherche in PsycINFO und PubMed fĂŒr den Zeitraum von 1976-2015 wurden Psychotherapiestudien gesucht, in denen Patienten mit Angstsymptomen einer SD- oder Placebo-Gruppe zugewiesen und verglichen wurden. Nach Extraktion der gewĂ€hlten Moderator-Variablen konnten 11 Studien eingeschlossen werden. Ergebnisse: Die Ergebnisse zu den spezifischen Effekten der SD waren nicht einheitlich. Eine durchgefĂŒhrte Moderator-Analyse zeigte, dass der Nachweis spezifischer Effekte von der GlaubwĂŒrdigkeit des Placebos und dem dabei erlebten Ausmaß emotionaler Erfahrungen abhĂ€ngig ist. Schlussfolgerung: Ob ein bestimmtes psychotherapeutisches Verfahren als spezifisch einzustufen ist, hĂ€ngt von der Operationalisierung der Placebo-Kontrolle ab. Insbesondere bei SD scheint die EinschrĂ€nkung des zu bearbeitenden Themas und in der Folge die Unterbindung der emotionalen Erfahrung des Patienten innerhalb der Kontrollbedingung eine Voraussetzung dafĂŒr zu sein, spezifische Effekte der SD zu finden

    Examining the relationship between home literacy environment and neural correlates of phonological processing in beginning readers with and without a familial risk for dyslexia: an fMRI study

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    Developmental dyslexia is a language-based learning disability characterized by persistent difficulty in learning to read. While an understanding of genetic contributions is emerging, the ways the environment affects brain functioning in children with developmental dyslexia are poorly understood. A relationship between the home literacy environment (HLE) and neural correlates of reading has been identified in typically developing children, yet it remains unclear whether similar effects are observable in children with a genetic predisposition for dyslexia. Understanding environmental contributions is important given that we do not understand why some genetically at-risk children do not develop dyslexia. Here we investigate for the first time the relationship between HLE and the neural correlates of phonological processing in beginning readers with (FHD+, n=29) and without (FHD−, n=21) a family history of developmental dyslexia. We controlled for socio-economic status to isolate the neurobiological mechanism by which HLE affects reading development. Group differences revealed stronger correlation of HLE with brain activation in the left inferior/middle frontal and right fusiform gyri in FHD− compared to FHD+ children, suggesting greater impact of HLE on manipulation of phonological codes and recruitment of orthographic representations in typically developing children. In contrast, activation in the right precentral gyrus showed a significantly stronger correlation with HLE in FHD+ compared to FHD− children, suggesting emerging compensatory networks in genetically at-risk children. Overall, our results suggest that genetic predisposition for dyslexia alters contributions of HLE to early reading skills before formal reading instruction, which has important implications for educational practice and intervention models

    NASA ESTO Lidar Technologies Investment Strategy: 2016 Decadal Update

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    The NASA Earth Science Technology Office (ESTO) recently updated its investment strategy in the area of lidar technologies as it pertains to NASA's Earth Science measurement goals in the next decade. The last ESTO lidar strategy was documented in 2006. The current (2016) report assesses the state-of-the-art in lidar technologies a decade later. Lidar technology maturation in the past decade has been evaluated, and the ESTO investment strategy is updated and laid out in this report according to current NASA Earth science measurement needs and new emerging technologies

    Machine Learning in Clinical Psychology and Psychotherapy Education: A Mixed Methods Pilot Survey of Postgraduate Students at a Swiss University

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    Background: There is increasing use of psychotherapy apps in mental health care.Objective: This mixed methods pilot study aimed to explore postgraduate clinical psychology students' familiarity and formal exposure to topics related to artificial intelligence and machine learning (AI/ML) during their studies.Methods: In April-June 2020, we conducted a mixed-methods online survey using a convenience sample of 120 clinical psychology students enrolled in a two-year Masters' program at a Swiss University.Results: In total 37 students responded (response rate: 37/120, 31%). Among respondents, 73% (n = 27) intended to enter a mental health profession, and 97% reported that they had heard of the term “machine learning.” Students estimated 0.52% of their program would be spent on AI/ML education. Around half (46%) reported that they intended to learn about AI/ML as it pertained to mental health care. On 5-point Likert scale, students “moderately agreed” (median = 4) that AI/M should be part of clinical psychology/psychotherapy education. Qualitative analysis of students' comments resulted in four major themes on the impact of AI/ML on mental healthcare: (1) Changes in the quality and understanding of psychotherapy care; (2) Impact on patient-therapist interactions; (3) Impact on the psychotherapy profession; (4) Data management and ethical issues.Conclusions: This pilot study found that postgraduate clinical psychology students held a wide range of opinions but had limited formal education on how AI/ML-enabled tools might impact psychotherapy. The survey raises questions about how curricula could be enhanced to educate clinical psychology/psychotherapy trainees about the scope of AI/ML in mental healthcare.</jats:p

    2016 Decadal Update of the NASA ESTO Lidar Technologies Investment Strategy

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    We describe the 2016 update of the NASA Earth Science Technology Office (ESTO) investment strategy in the area of lidar technologies as pertaining to NASAs Earth Science measurement goals in the next decade

    Role of quantum coherence in chromophoric energy transport

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    The role of quantum coherence and the environment in the dynamics of excitation energy transfer is not fully understood. In this work, we introduce the concept of dynamical contributions of various physical processes to the energy transfer efficiency. We develop two complementary approaches, based on a Green's function method and energy transfer susceptibilities, and quantify the importance of the Hamiltonian evolution, phonon-induced decoherence, and spatial relaxation pathways. We investigate the Fenna-Matthews-Olson protein complex, where we find a contribution of coherent dynamics of about 10% and of relaxation of 80%.Comment: 5 pages, 3 figures, included static disorder, correlated environmen

    NASA ESTO Lidar Technologies Investment Strategy: 2016 Decadal Update

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    The NASA Earth Science Technology Office (ESTO) recently updated its investment strategy in the area of lidar technologies as it pertains to NASAs Earth Science measurement goals in the next decade. The last ESTO lidar strategy was documented in 2006. The current (2016) report assesses the state-of-the-art in lidar technologies a decade later. Lidar technology maturation in the past decade has been evaluated, and the ESTO investment strategy is updated and laid out in this report according to current NASA Earth science measurement needs and new emerging technologies
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