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911.
Crits-Christoph Paul; Gibbons Mary Beth Connolly; Hamilton Jessica; Ring-Kurtz Sarah; Gallop Robert 《Canadian Metallurgical Quarterly》2011,79(3):267
Objective: To examine the dependability of alliance scores at the patient and therapist level, to evaluate the potential causal direction of session-to-session changes in alliance and depressive symptoms, and to investigate the impact of aggregating the alliance over progressively more sessions on the size of the alliance–outcome relationship. Method: We used data from a study (N = 45 patients; N = 9 therapists) of psychotherapy for major depressive disorder in which the alliance was measured at every treatment session to calculate generalizability coefficients and to predict change in depressive symptoms from alliance scores. Two replication samples were also used. Results: At the therapist level, a large number of patients (about 60) per therapist is needed to provide a dependable therapist-level alliance score. At the patient level, generalizability coefficients revealed that a single assessment of the alliance is only marginally acceptable. Very good (>.90) dependability at the patient level is only achieved through aggregating 4 or more assessments of the alliance. Session-to-session change in the alliance predicted subsequent session-to-session changes in symptoms. Evidence for reverse causation was found in later-in-treatment sessions, suggesting that only aggregates of early treatment alliance scores should be used to predict outcome. Session 3 alliance scores explained 4.7% of outcome variance, but the average of Sessions 3–9 explained 14.7% of outcome variance. Conclusion: Adequate assessment of the alliance using multiple patients per therapist and at least 4 treatment sessions is crucial for fully understanding the size of the alliance–outcome relationship. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
912.
Tanya N. Beran Alejandro Ramirez-Serrano Roman Kuzyk Meghann Fior Sarah Nugent 《International journal of human-computer studies》2011,69(7-8):539-550
Centuries ago, the existence of life was explained by the presence of a soul (Tylor, 1871). Known as animism, this term was re-defined in the 1970s by Piaget as young children's beliefs that inanimate objects are capable of actions and have life-like qualities. With the development of robots in the 21st century, researchers have begun examining whether animism is apparent in children's impressions of robots. The purpose of this study was to use a model of knowledge structures, or schemata, to examine whether children attribute human qualities of cognition, affect, and behavior to a robot. An experiment was set up at a science center located in a major Western Canadian city, and visitors to the center were invited to participate. A total of 198 children ages 5–16 years (M=8.18 years) with an approximate even number of boys and girls were included. Children completed a semi-structured interview after observing a robot, a small 5 degree of freedom robot arm, perform a block stacking task. Answers to the nine questions about the robot were scored according to whether they referenced humanistic qualities. Results from frequency and content analyses suggest that a significant proportion of children ascribe cognitive, behavioral, and especially affective, characteristics to robots. 相似文献
913.
914.
Jessica M. Walker Bartosz Marzec Renee B. Y. Lee Kristyna Vodrazkova Sarah J. Day Chiu C. Tang Rosalind E. M. Rickaby Fabio Nudelman 《Advanced functional materials》2019,29(1)
Coccolith‐associated polysaccharides (CAPs) are thought to be a key part of the biomineralization process in coccolithophores; however, their role is not fully understood. Two different systems that promote different polymorphs of calcium carbonate are used to show the effect of CAPs on nucleation and polymorph selection in vitro. Using a combination of time‐resolved cryo‐transmission electron microscopy and scanning electron microscopy, the mechanisms of calcite nucleation and growth in the presence of the intracrystalline fraction are examined containing CAPs extracted from coccoliths from Gephyrocapsa oceanica and Emiliania huxleyi, two closely related coccolithophore species. The CAPs extracted from G. oceanica are shown to promote calcite nucleation in vitro, even under conditions favoring the kinetic products of calcium carbonate, vaterite, and aragonite. This is not the case with CAPs extracted from E. huxleyi, suggesting that the functional role of CAPs in vivo may be different between the two species. Additionally, high‐resolution synchrotron powder X‐ray diffraction has revealed that the polysaccharide is located between grain boundaries of both calcite produced in the presence of the CAPs in vitro and biogenic calcite, rather than within the crystal lattice. 相似文献
915.
Eric C. Wu Charlene Z. Salamat Omar León Ruiz Thomas Qu Alexis Kim Sarah H. Tolbert Benjamin J. Schwartz 《Advanced functional materials》2023,33(19):2213652
When an electron is removed from a conjugated polymer, such as poly(3-hexylthiophene-2,5-diyl) (P3HT), the remaining hole and associated change in the polymer backbone structure from aromatic to quinoidal are referred to as a polaron. Bipolarons are created by removing the unpaired electron from an already-oxidized polymer segment. In electrochemically-doped P3HT films, polarons, and bipolarons are readily observed, but in chemically-doped P3HT films, bipolarons rarely form. This is explained by studying the effects of counterion position on the formation of polarons, strongly coupled polarons, and bipolarons using both spectroscopic and X-ray diffraction experiments and time-dependent density functional theory calculations. The counterion positions control whether two polarons spin-pair to form a bipolaron or whether they strongly couple without spin-pairing are found. When two counterions lie close to the same polymer segment, bipolarons can form, with an absorption spectrum that is blueshifted from that of a single polaron. Otherwise, polarons at high concentrations do not spin-pair, but instead J-couple, leading to a redshifted absorption spectrum. The counterion location needed for bipolaron formation is accompanied by a loss of polymer crystallinity. These results explain the observed formation order of single polarons, coupled single polarons, and singlet bipolarons in electrochemically- and chemically-doped conjugated polymers. 相似文献
916.
Rimoon Agaiby Yang Yang Sarah H. Olsen Anthony G. ONeill Geert Eneman Peter Verheyen Roger Loo Cor Claeys 《Solid-state electronics》2007,51(11-12):1473
Electrical results are presented for deep submicron strained Si MOSFETs fabricated on both thick and thin SiGe strain relaxed buffers, SRBs. For the first time thin SRB devices are shown to offer the same performance enhancements as thick SRB devices. The reduction in performance enhancement with device scaling widely reported in the literature has also been investigated. Correcting for dynamic self-heating effects using ac measurements, the enhancements seen in long channel devices are maintained down to short channel lengths, demonstrating the scalability of SRB technology. Thermal resistances have been measured experimentally and compared with analytical models. The thermal resistance for devices on the thin SRBs is reduced by 50% compared with devices on thick SRBs. Finally, a comparison of self-heating effects in MOSFETs fabricated on SOI and Si0.8Ge0.2 SRBs provides insight into the challenges ahead as power densities continue to increase. 相似文献
917.
A dynamic procedure for selective information fusion from multiple image frames is derived from robust error estimation theory. The fusion rate is driven by the anisotropic gain function, defined to be the difference between the Gaussian smoothed-edge maps of a given input frame and of an evolving synthetic output frame. The gain function achieves both selection and rapid fusion of relatively sharper features from each input frame compared to the synthetic frame. Effective applications are demonstrated for image sharpening in imaging through atmospheric turbulence, for multispectral fusion of the RGB spectral components of a scene, for removal of blurred visual obstructions from in front of a distant focused scene, and for high-resolution two-dimensional display of three-dimensional objects in microscopy. 相似文献
918.
Sarah J. Boehm Lei Kang Douglas H. Werner Christine D. Keating 《Advanced functional materials》2017,27(5)
Reconfigurability is one of the most critical properties of nanophotonic systems and, consequently, methods for enabling a significant degree of functionality are highly sought after. However, dynamically responsive control in top‐down fabricated photonic structures often requires extreme conditions and yields moderate modulation capability. In sharp contrast to top‐down methods, directed self‐assembly of micro‐ and nanoparticles offers a distinct avenue for reconfigurable photonics. In the present work, gold nanowire lattices are formed via electric field directed assembly in order to take advantage of their collective optical properties. The lattices are reconfigured on‐demand between two different functional states, in the form of broadband polarizers. By selectively switching the electric field between two orthogonal electrode pairs, a maximum transmission contrast of ≈50% is observed in the near‐infrared regime. Moreover, the reconfigurable transmission spectra, which are highly dependent on the nanowire size and electric field conditions, are reversible. The demonstrated proof‐of‐concept nanowire lattice polarizer provides potential for electrically reconfigurable photonic devices such as ultra‐compact polarization components, electro‐optic switches, and on‐chip modulators. 相似文献
919.
Ángel Enríquez Sarah Libring Tyler C. Field Julian Jimenez Taeksang Lee Hyunsu Park Douglas Satoski Michael K. Wendt Sarah Calve Adrian Buganza Tepole Luis Solorio Hyowon Lee 《Advanced functional materials》2021,31(1):2005021
Accurately replicating and analyzing cellular responses to mechanical cues is vital for exploring metastatic disease progression. However, many of the existing in vitro platforms for applying mechanical stimulation seed cells on synthetic substrates. To better recapitulate physiological conditions, a novel actuating platform is developed with the ability to apply tensile strain on cells at various amplitudes and frequencies in a high-throughput multi-well culture plate using a physiologically relevant substrate. Suspending fibrillar fibronectin across the body of the magnetic actuator provides a matrix representative of early metastasis for 3D cell culture that is not reliant on a synthetic substrate. This platform enables the culturing and analysis of various cell types in an environment that mimics the dynamic stretching of lung tissue during normal respiration. Metabolic activity, YAP activation, and morphology of breast cancer cells are analyzed within one week of cyclic stretching or static culture. Further, matrix degradation is significantly reduced in breast cancer cell lines with metastatic potential after actuation. These new findings demonstrate a clear suppressive cellular response due to cyclic stretching that has implications for a mechanical role in the dormancy and reactivation of disseminated breast cancer cells to macrometastases. 相似文献
920.
Xu Xiao Patrick Urbankowski Kanit Hantanasirisakul Yao Yang Stephen Sasaki Long Yang Chi Chen Hao Wang Ling Miao Sarah H. Tolbert Simon J. L. Billinge Hctor D. Abrua Steven J. May Yury Gogotsi 《Advanced functional materials》2019,29(17)
Ultrathin and 2D magnetic materials have attracted a great deal of attention recently due to their potential applications in spintronics. Only a handful of stable ultrathin magnetic materials have been reported, but their high‐yield synthesis remains a challenge. Transition metal (e.g., manganese) nitrides are attractive candidates for spintronics due to their predicted high magnetic transition temperatures. Here, a lattice matching synthesis of ultrathin Mn3N2 is employed. Taking advantage of the lattice match between a KCl salt template and Mn3N2, this method yields the first ultrathin magnetic metal nitride via a solution‐based route. Mn3N2 flakes show intrinsic magnetic behavior even at 300 K, enabling potential room‐temperature applications. This synthesis procedure offers an approach to the discovery of other ultrathin or 2D metal nitrides. 相似文献