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31.
L. Adrianne Bonham Jo Ann I. Luckie 《Community College Journal of Research & Practice》2013,37(6):543-554
One fact often overlooked in discussing the retention issue is that not everyone who fails to return to school is a dropout. Some persons return after an absence of a semester or more; they can be called stopouts. Some intended to take only a few classes and stop attending when they accomplish their educational goals; they can be called optouts. The only persons who should be labeled dropouts are those who failed to accomplish their educational goal and have no definite plans to accomplish it later. During the 1990‐91 school year, Del Mar College (DMC) and the Texas A&M Adult and Extension Education program developed and executed a plan to identify, count, and interview nonreturnees at DMC. The purposes of the study were toprovide DMC with baseline data on its nonreturnees and to test the feasibility of gathering interview information by telephone. Stopouts far outnumbered dropouts and optouts among respondents, with 303 of 399 nonreturnees identifying themselves as such. In this article, we define relevant terms, outline the data‐gathering process and describe the findings of the present study, and present recommendations regarding data gathering and the focus of retention efforts. 相似文献
32.
In the context of Learning Technologies, the need to be able to assess the learning and domain comprehension in open-ended learner responses has been present in artificial intelligence and education since its beginnings. The advantage of using summaries is that they allow teachers to diagnose comprehension and the amount of information remembered from text in the learning process. This study addresses the issue of automatically obtaining overall discourse scores from surface discourse measures for Basque language. Global measures have been studied for cohesion, adequacy and use of language. The approach taken was to estimate the presence of the automatically gathered surface discourse measures in expert grading decisions in cohesion, adequacy and use of language. As a consequence, three grading decision-making regression models were obtained to estimate overall grades from text written in Basque. Next, the obtained regression models were tested in corpus-containing summaries written by learners with different degrees of summarisation maturity. The results show that the obtained grading frameworks significantly reflect human decisions and are able to discriminate summarisation maturity differences. 相似文献
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34.
A simple experimental setup to study the impact and coalescence of deposited droplets is described. Droplet impact and coalescence have been investigated by high-speed particle image velocimetry. Velocity fields near the liquid-substrate interface have been observed for the impact and coalescence of 2.4 mm diameter droplets of glycerol∕water striking a flat transparent substrate in air. The experimental arrangement images the internal flow in the droplets from below the substrate with a high-speed camera and continuous laser illumination. Experimental results are in the form of digital images that are processed by particle image velocimetry and image processing algorithms to obtain velocity fields, droplet geometries, and contact line positions. Experimental results are compared with numerical simulations by the lattice Boltzmann method. 相似文献
35.
G. M. Sankolli M. I. Khatkhatay M. P. Desai D. K. Pardhe P. C. Ishrad U. M. Joshi 《Indian journal of clinical biochemistry : IJCB》1992,7(1):71-74
Aprototype kit for the detection of occurrence of ovulation based on urinary pregnanediol glucuronide estimations by ELISA
was developed in our laboratory. This kit was sent for evaluation at 4 centres in Bombay and Pune, India. The diagnosis of
ovulation/anovulation based on the results of the kit is comparable with that based on reference parameters commonly used
(ultrasonography of ovarian follicles and serum progesterone estimations). The accuracy of the test was 93.5%, specificity
was 87.5% and sensitivity was 95.7%. This rapid indigenous test can be very useful in assessing ovulatory status of the woman
by the clinicians in their offices. 相似文献
36.
Ivan Bradaric Athina P. Petropulu Konstantinos I. Diamantaras 《Journal of The Franklin Institute》2002,339(2):161-187
Higher-order statistics (HOS) are well known for their robustness to additive Gaussian noise and ability to preserve phase. HOS estimates, on the other hand, have been criticized for high complexity and the need for long data in order to maintain small variance. Since rank reduction offers a general principle for reduction of estimator variance and complexity, we consider the problem of designing low-rank estimators for HOS. We propose three methods for choosing the transformation matrix that reduces the mean-square error (MSE) associated with the low-rank HOS estimates. We also demonstrate the advantages of using low-rank third-order moment estimates for blind system estimation. Results indicate that the full rank MSE corresponding to some data length N can be attained by a low-rank estimator corresponding to a length significantly smaller than N. 相似文献
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38.
J. I. Anetor F I Ajose T. S Akingbola 《Indian journal of clinical biochemistry : IJCB》2005,20(1):193-197
A 64-year-old security guard and longstanding known hypertensive presented with hypertensive heart disease (HHD), weight loss,
an enlarged prostate, and a spontaneously fractured rib. Malignancy of the prostate with possible metastases to the ribs was
strongly suspected. Biochemical profiling revealed a paraprotein. Other biochemical and hematological correlates that were
on hand before serum protein electrophoresis were rather atypical. Paraprotein studies by immunofixation revealed IgA myelomatosis.
Unlike previous reports from Caucasians there was normocalcaemia, normal protein level, microcytic hypochromia, low MCHC,
cholesterol level at the lower limit of the reference range and normal urea level (in the face of markedly raised creatinine
level). Nutritional modulation of the classical laboratory features of this disease may account for the fairly atypical laboratory
picture.
The need to appreciate the influence of nutritional status on the laboratory (especially biochemical) features of a disease
and thus interpretation of diagnostic tests appears of exceptional current importance, given the widening gap in socioeconomic
status and the level of poverty between the resource poor and developed countries from which the classical, clinical and laboratory
features of most diseases were first described.
This case report reminds of the need not only to recognize theoretically the impact of nutritional status on the laboratory
characteristics of a disease but of the practical application of the nutritional perspective in the interpretation of diagnostic
investigations, especially in nutritionally disadvantaged communities. 相似文献
39.
40.
M. Jeanne Wilcox Shelley I. Gray Amy B. Guimond Addie E. Lafferty 《Early childhood research quarterly》2011,26(3):278-294
The purpose of this investigation was to examine the efficacy of a new preschool oral language and early literacy curriculum package (Teaching Early Literacy and Language [TELL]) for children with developmental speech and/or language impairment (DSLI) either as a primary (e.g., specific to speech and/or language) or secondary impairment (e.g., developmental delay that includes DSLI). Participants included 118 children (30 females, 88 males, M age = 53.58 months) with DLSI and their 29 preschool teachers. The design was a randomized controlled trial (RCT) with assignment to experimental versus contrast conditions at the classroom level. Teachers in TELL classes received formal training, in-class support, and mentoring to implement the curriculum. Dependent measures for the children included scores on the Clinical Evaluation of Language Fundamentals-Preschool 2nd edition (CELF-P2), the Phonological Awareness Literacy Screening for Preschool (PALS-PreK), the Renfrew Bus Story (BUS), and a receptive and expressive vocabulary measure developed for this investigation (VOCAB). Results indicated that when compared to the contrast group, children in the TELL condition demonstrated greater gains on the phonological awareness subtest of the CELF-P2, the sentence length score of the BUS, the letter sounds, beginning sound awareness, and rhyme awareness subtests of the PALS-PreK, and VOCAB. Results suggest that the TELL curriculum package has promise for promoting gains in early literacy and oral language skills in preschool children with DLSI. 相似文献