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971.
The specific heat and magnetocaloric effect (MCE) of A-site ordered PrBaMn2O6 manganite have been studied. The anomalies caused by the ferromagnetic (FM) and antiferromagnetic (AFM) phase transitions are revealed in the specific heat curve. Direct and inverse MCE are observed at the Curie and Néel points correspondingly. A value of the inverse MCE in the heating run is smaller than in the cooling regime. We attribute this effect to the competition between FM and AFM interactions. A significant advantage of PrBaMn2O6 as a magnetocaloric material is an MCE spanning a broad range of temperature with a maximum at room temperature. 相似文献
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Yu.B. Bolkhovityanov A.S. Deryabin A.K. Gutakovskii L.V. Sokolov 《Philosophical Magazine Letters》2013,93(7):458-464
Edge misfit dislocations (MDs) formed as result of reactions between 60° glissile threading dislocations and 60° MDs lying on an intersecting glide plane were found in strained GeSi-on-Si(001) and Ge-on-InGaAs/GaAs films. It was demonstrated that dislocations penetrating from the InGaAs buffer layer to the strained Ge film can provoke formation of not only 60° MDs, but also edge MDs on the interface even at minor mismatch of the lattice parameters of the film and the InGaAs/GaAs virtual substrate. 相似文献
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Anke Ehlers Nick Grey Jennifer Wild Richard Stott Sheena Liness Alicia Deale Rachel Handley Idit Albert Deborah Cullen Ann Hackmann John Manley Freda McManus Francesca Brady Paul Salkovskis David M. Clark 《Behaviour research and therapy》2013,51(11):742-752
ObjectiveTrauma-focused psychological treatments are recommended as first-line treatments for Posttraumatic Stress Disorder (PTSD), but clinicians may be concerned that the good outcomes observed in randomized controlled trials (RCTs) may not generalize to the wide range of traumas and presentations seen in clinical practice. This study investigated whether Cognitive Therapy for PTSD (CT-PTSD) can be effectively implemented into a UK National Health Service Outpatient Clinic serving a defined ethnically mixed urban catchment area.MethodA consecutive sample of 330 patients with PTSD (age 17–83) following a wide range of traumas were treated by 34 therapists, who received training and supervision in CT-PTSD. Pre and post treatment data (PTSD symptoms, anxiety, depression) were collected for all patients, including dropouts. Hierarchical linear modeling investigated candidate moderators of outcome and therapist effects.ResultsCT-PTSD was well tolerated and led to very large improvement in PTSD symptoms, depression and anxiety. The majority of patients showed reliable improvement/clinically significant change: intent-to-treat: 78.8%/57.3%; completer: 84.5%/65.1%. Dropouts and unreliable attenders had worse outcome. Statistically reliable symptom exacerbation with treatment was observed in only 1.2% of patients. Treatment gains were maintained during follow-up (M = 280 days, n = 220). Few of the selection criteria used in some RCTs, demographic, diagnostic and trauma characteristics moderated treatment outcome, and only social problems and needing treatment for multiple traumas showed unique moderation effects. There were no random effects of therapist on symptom improvement, but therapists who were inexperienced in CT-PTSD had more dropouts than those with greater experience.ConclusionsThe results support the effectiveness of CT-PTSD and suggest that trauma-focused cognitive behavior therapy can be successfully implemented in routine clinical services treating patients with a wide range of traumas. 相似文献
976.
Previous studies have demonstrated that animals use multiple strategies to solve spatial tasks. We used a T-maze to examine spatial behavior in crayfish, using visual and tactile stimuli as place cues and a food-scented escape tank as reinforcement to leave the maze. In trials on a single day and across multiple days, crayfish learned to exit the maze with significantly reduced latency and with fewer turns. In addition, we examined place memory in 40-min periods with the maze closed and found that crayfish spent longer in the vicinity of a previously open exit compared to a closed exit. Probe tests were conducted using a forced-choice procedure to determine whether crayfish remembered the route out of the maze using primarily place cues or response learning. We found that approximately equal numbers of animals used each strategy, and individuals were able to switch from one strategy to the other on different test days. Males and females did not differ significantly in their performance in the place memory test, maze exit task, or probe tests. Both sexes displayed place memory for the exit location and reduced latency to exit during trials 24 h, 48 h, 72 h, and 1 week after initial training trials, suggesting that spatial memories in crayfish are relatively enduring. 相似文献
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Jose Prados Beatriz Alvarez Joanna Howarth Katharine Stewart Claire L. Gibson Claire V. Hutchinson Andrew M. J. Young Colin Davidson 《Animal cognition》2013,16(2):177-186
The learning abilities of planarian worms (Dugesia tigrina) were assessed by using a number of Pavlovian conditioning paradigms. Experiment 1 showed that planaria were susceptible to basic conditioning in that they readily developed a conditioned response to a change in ambient luminance when it was consistently paired with an electric shock over a number of trials. In Experiment 2, the change in luminance was presented in a compound with a vibration stimulus during conditioning. Subsequent tests revealed poor conditioning of the elements compared with control groups in which the animals were conditioned in the presence of the elements alone, an instance of overshadowing. In Experiment 3, pre-training of one of the elements before compound conditioning resulted in blocking of learning about the other element. These results add to other studies that have reported cue competition effects in animal species belonging to different phyla (chordate, mollusk, arthropod), suggesting that learning in these phyla could be ruled by similar principles. The results are discussed adopting an evolutionary-comparative approach. 相似文献
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As a result of our technological advances in space exploration, human enterprise is no longer limited to the confines of planet Earth. Although several philosophical approaches to environmental ethics have already been advocated for human encounters with other planets such as Mars, it may be argued that various religious worldviews will significantly influence these suggested value systems. In this article, we present an Eastern Orthodox Christian interpretation of Creation and explore the theological meaning of the human vocation as Priests of Creation. An appropriate application of these two principles provides a theological basis for an interplanetary eco-praxis. 相似文献