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11.
This study's primary purpose was to examine the relative contribution of social-behavioral predictors to reading and math skills. The study expands on Duncan et al.'s (2007) work by using longitudinal methodology from the National Institute of Child Health and Human Development's Study of Child Care and Youth Development (SECCYD) and the Early Childhood Longitudinal Study, Kindergarten Class of 1998–1999 (ECLS-K) databases, and by focusing on potential differences in patterns of early predictors of later reading and math trajectories for African American versus Caucasian students. Predictor measures were selected at kindergarten, and the outcomes included standardized reading and math scores obtained from Grades 1, 3, 5, and 9 for the SECCYD sample, and Grades 3, 5, and 8 for the ECLS-K sample. Consistent with Duncan et al.'s findings, results reflect the relative contributions of early reading and math skills to later functioning in these respective academic domains for both samples, and there are indications for the importance of early expressive language skills to both reading and math in the SECCYD sample. Findings related to the power of social-behavioral predictors, however, are not consistent across samples. Although the SECCYD sample evidenced no such predictors, several interactions in the ECLS-K sample suggested the moderating effects of early ratings of aggressive behaviors and internalizing behaviors on later reading and math for African American students. The moderating effects of early teacher ratings of attention and internalizing behaviors for African American students as compared with Caucasian students in later math growth also were noted. The importance of early social-behavioral functions as related to later academic skills remains an important area of inquiry. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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An alternative implementation of an algorithm for the computation of the multivariable stability margin to check the robust stability of feedback systems with real parametric uncertainty is proposed. This method eliminates the need for the frequency search by reducing it to the testing of a finite number of conditions. These conditions have a special structure that allows a significant improvement in the speed of computation  相似文献   
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Summary In this paper, we present a solution to the problem of free vibrations of the human head system taking into account the dissipative behaviour of the brain. The mathematical model is based on the three-dimensional theory of viscoelasticity and the representation of the displacement field in terms of the Navier eigenvectors. The frequency equation is solved numerically and the results for eigenfrequencies and damping coefficients are presented for various geometrical and physical parameters of the system. The results obtained are in excellent agreement with the measured eigenfrequencies, and the predicted damping coefficients are within the order of magnitude of the measured ones. From the proposed analysis we have obtained the information that the role of the viscoelastic neck as well as the viscoelastic properties of the skull-brain system have to be simultaneously taken into account in the study of the frequency spectrum of the human head. The analysis of the realistic model is under preparation.  相似文献   
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Learning convergence in the cerebellar model articulationcontroller   总被引:10,自引:0,他引:10  
A new way to look at the learning algorithm in the cerebellar model articulation controller (CMAC) proposed by J.S. Albus (1975) is presented. A proof that the CMAC learning always converges with arbitrary accuracy on any set of training data is obtained. An alternative way to implement CMAC based on the insights obtained in the process is proposed. The scheme is tested with a computer simulation for learning the inverse dynamics of a two-link robot arm.  相似文献   
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Eosinophils are emerging as an increasingly important cell in the immunoregulatory network of normal and pathological processes. No studies has yet described optimized experimental strategies to transfect DNA into human eosinophils. Using a frequently employed in vitro model of human eosinophil, the EoL-1 cells, we now described the optimal transfection of DNA into these cells by electroporation. Our results indicate that electroporation can efficiently and reproducibly transfect DNA into EoL-1 cells. Optimal electroporation conditions consist of the use of 1 X RPMI medium 1640 with 10% FBS, voltage setting at 275 V, 1150 microF capacitance, 40 mg of DNA and 4.0 X 10(7) cells/ml per electroporation in a total volume of 0.5 ml in 0.4 cm gap cuvettes. These conditions may be a useful protocol for transfecting eosinophil cell lines.  相似文献   
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OBJECTIVES: The aim of this study was to assess the incidence of incontinence and impotence in patients following total prostatectomy and assess the impact their symptoms have on their quality of life. PATIENTS AND METHODS: Between 1987 and 1994, one surgeon performed retropubic total prostatectomies on 89 patients, of which 87 were available for follow-up. All patients were sent an ICS-male questionnaire. Patients' ages ranged from 49 to 73 years (median 65). The interval between surgery and completing the questionnaire ranged from 7 to 87 months (median 22). RESULTS: The response rate was 95%. No patients reported incontinence pre-operatively. Postoperatively, 69% (57/83) of patients suffered to some degree of leakage of urine and 24% (29/83) used pads. Of these, 60% used 1 pad per day, 15% 2 pads and 25% (5 patients) used 3 or more. Nocturnal incontinence was reported by 20% of patients. Urinary incontinence was considered a problem in only 34% (28/83) of patients. Sixty-five percent of patients using pads considered urinary leakage to be a problem, but only 1 considered it a serious problem. 89% claimed to have been potent prior to surgery. The overall postoperative potency rate was 41% (30/74) in those potent pre-operatively. However, 67% of patients reporting potency had severely reduced rigidity, and only 12% (9/74) achieved what they considered full erections. Ten percent of all patients considered postoperative impotence to be a serious problem, and 47% stated that it was not a problem at all. CONCLUSIONS: The incidence of incontinence and impotence following total prostatectomy is higher than earlier reports suggest, but the impact of these complications appears to be surprisingly low. These results allow patients to be given realistic expectations when counselled prior to this operation.  相似文献   
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Nutrient Cycling in Agroecosystems - Precise knowledge of safflower (Carthamus tinctorius L.) nitrogen (N) dynamics is essential to optimize crop nutrition and minimize environmental impacts of...  相似文献   
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Tremor is the most common motor disorder of Parkinson's disease (PD) and consequently its detection plays a crucial role in the management and treatment of PD patients. The current diagnosis procedure is based on subject-dependent clinical assessment, which has a difficulty in capturing subtle tremor features. In this paper, an automated method for both resting and action/postural tremor assessment is proposed using a set of accelerometers mounted on different patient's body segments. The estimation of tremor type (resting/action postural) and severity is based on features extracted from the acquired signals and hidden Markov models. The method is evaluated using data collected from 23 subjects (18 PD patients and 5 control subjects). The obtained results verified that the proposed method successfully: 1) quantifies tremor severity with 87 % accuracy, 2) discriminates resting from postural tremor, and 3) discriminates tremor from other Parkinsonian motor symptoms during daily activities.  相似文献   
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