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21.
Campbell Susan B.; Matestic Patricia; von Stauffenberg Camilla; Mohan Roli; Kirchner Thomas 《Canadian Metallurgical Quarterly》2007,43(5):1202
Using data from the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development, the authors modeled trajectories of maternal depressive symptoms from infant age 1 month to 7 years. The authors identified 6 trajectories of maternal depressive symptoms: high-chronic, moderate-increasing, high-decreasing, intermittent, moderate-stable, and low-stable. Women on these depression trajectories varied in sociodemographic risk and in changes in observed maternal sensitivity over time. Maternal sensitivity was generally higher and increased when depressive symptoms were low; sensitivity was lower and decreased when depressive symptoms were either high or increasing. Child outcomes at 1st grade were examined by trajectory group. The authors discuss the complexity of disentangling maternal symptoms from maternal sensitivity and sociodemographic risk when predicting children's functioning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
22.
Oil Spill Detection in Radarsat and Envisat SAR Images 总被引:8,自引:0,他引:8
Anne H. S. Solberg Camilla Brekke Per Ove Husoy 《Geoscience and Remote Sensing, IEEE Transactions on》2007,45(3):746-755
We present algorithms for automatic detection of oil spills in synthetic aperture radar (SAR) images. The algorithms consist of three main parts, namely: 1) detection of dark spots; 2) feature extraction from the dark spot candidates; and 3) classification of dark spots as oil spills or look-alikes. The algorithms have been trained on a large number of Radarsat and Envisat Advanced Synthetic Aperture Radar (ASAR) images. The performance of the algorithm is compared to manual and semiautomatic approaches in a benchmark study using 59 Radarsat and Envisat images. The algorithms can be considered to be a good alternative to manual inspection when large ocean areas are to be inspected 相似文献
23.
Camilla B. Schwind 《Computational Intelligence》1990,6(3):172-178
In this paper, we present a formalism called feature grammar and its application to several problems of semantic analysis. Our extension concerns the structure of the feature value sets, which can be complex, and the definition of unification, which is dependent on this structure. Moreover, we introduce generation rules for feature symbols in order to determine well-formed symbols, which form the alphabet of a formal language for natural language analysis. 相似文献
24.
Research from the individual-differences tradition pertinent to the optimal development of exceptional talent is reviewed, using the theory of work adjustment (TWA) to organize findings. The authors show how TWA concepts and psychometric methods, when used together, can facilitate positive development among talented youth by aligning learning opportunities with salient aspects of each student's individuality. Longitudinal research and more general theoretical models of (adult) academic and intellectual development support this approach. This analysis also uncovers common threads running through several positive psychological concepts (e.g., effectance motivation, flow, and peak experiences). The authors conclude by underscoring some important ideals from counseling psychology for fostering intellectual development and psychological well-being. These include conducting a multifaceted assessment, focusing on strength, helping people make choices, and providing a developmental context for bridging educational and industrial psychology to facilitate positive psychological growth throughout the life span. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
25.
The performance of mathematically talented 12- and 13-year-olds on various cognitive tasks was compared with that of average-ability youth, verbally talented youth, and college students. In Experiment 1, the hypothesis that mathematical talent includes enhanced problem-translation skills was supported: The mathematically talented students were better than other groups at writing equations expressing complex relationships. Although the mathematically talented group outperformed their average-ability peers, they were no better than the verbally talented group or the college students in rewriting and recalling the propositions in an algebra story problem. In Experiment 2, the hypothesis that mathematical talent includes enhanced ability to represent and manipulate information in short-term memory was strongly supported: the mathematically talented youth outperformed the other youth and, in most cases, performed as well as or better than the college students. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
26.
Yi Pang Lu-Tai Tien Hobart Zhu Juying Shen Camilla F. Wright Tembra K. Jones Samir A. Mamoon Abhay J. Bhatt Zhengwei Cai Lir-Wan Fan 《International journal of molecular sciences》2015,16(4):8635-8654
Our previous study showed that a single lipopolysaccharide (LPS) treatment to neonatal rats could induce a long-lasting neuroinflammatory response and dopaminergic system injury late in life. This is evidenced by a sustained activation of microglia and elevated interleukin-1β (IL-1β) levels, as well as reduced tyrosine hydroxylase (TH) expression in the substantia nigra (SN) of P70 rat brain. The object of the current study was to test whether co-administration of IL-1 receptor antagonist (IL-1ra) protects against LPS-induced neurological dysfunction later in life. LPS (1 mg/kg) with or without IL-1ra (0.1 mg/kg), or sterile saline was injected intracerebrally into postnatal day 5 (P5) Sprague-Dawley male rat pups. Motor behavioral tests were carried out from P7 to P70 with subsequent examination of brain injury. Our results showed that neonatal administration of IL-1ra significantly attenuated LPS-induced motor behavioral deficits, loss of TH immunoreactive neurons, as well as microglia activation in the SN of P70 rats. These data suggest that IL-1β may play a pivotal role in mediating a chronic neuroinflammation status by a single LPS exposure in early postnatal life, and blockading IL-1β might be a novel approach to protect the dopaminergic system against perinatal infection/inflammation exposure. 相似文献
27.
C. Galletti A. Paglianti K. C. Lee M. Yianneskis 《Chemical Engineering Communications》2013,200(4):516-531
Flow instabilities associated with changes in the clearance (C) of a Rushton impeller from the bottom of a stirred vessel of diameter T?=?294?mm were studied experimentally with laser Doppler anemometry. It is shown that for C/T?=?0.17–0.18 flow changes from a double- to a single-loop pattern occur randomly. The transition from one regime to the other is characterized by periodic oscillations at a frequency (f) related to the impeller speed (N) by f/N?=?0.135. The lifetimes of the stable and unstable patterns were found to be affected by fluid density and viscosity as well as clearance. The implications of the results for both mixing processes in stirred vessels and related predictions of the flows are discussed. 相似文献
28.
Federica Benvenuti Carlo Carlini Mario Marchionna Renata Patrini Anna Maria Raspolli Galletti Glauco Sbrana 《Journal of Inorganic and Organometallic Polymers》1997,7(3):183-201
The synthesis and structural characterization of a novel bidentate ligand such as bis(diphenylphosphino) methane bound to a cross-linked styrene/divinylbenzene resin and to linear poly(styrene) are reported. Moreover, the anchoring of palladium acetate to the above polymeric ligands is described and the structure of the heterogenized palladium(II) complexes obtained is proposed. 相似文献
29.
Antifouling agent release from marine coatings-ion pair formation/dissolution for controlled release 总被引:2,自引:0,他引:2
In marine coatings, the ability to sustain constant release of antifouling agents (AFA(s)) over a long period of time has become increasingly important. One efficient approach to prevent that diffusion depletes the paint film's antifouling activity is to adsorb the AFA strongly to a specie with low translational mobility, such as a high molecular weight polymer. Therefore, the AFA, Medetomidine, was adsorbed onto a sulfonated polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (SDPS) generating a Medetomidine–SDPS ion pair in an organic solvent. The interaction was investigated by 1H NMR in butanol (BuOH-d10) and on solid surfaces by the quartz crystal microbalance with dissipation monitoring technique (QCM-D) in two different solvents, seawater and o-xylene. From the NMR studies in butanol (BuOH-d10), a strong interaction between Medetomidine and SDPS was observed. From the QCM-D measurements, differences in affinity between Medetomidine and the SDPS was observed when changing from seawater to o-xylene. In seawater, the interaction was weak and displayed a large degree of reversibility compared to in o-xylene, where the interaction was strong and almost irreversible. Different swelling behaviour was also observed at the solid surfaces depending on the solvent used with o-xylene exhibiting the largest swelling of the polymer layer. 相似文献
30.