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31.
Preschoolers’ conceptual understanding and procedural skills were examined so as to explore the role of number‐words and concept–procedure interactions in their additional knowledge. Eighteen three‐ to four‐year‐olds and 24 four‐ to five‐year‐olds judged commutativity and associativity principles and solved two‐term problems involving number words and unknown numbers. The older preschoolers outperformed younger preschoolers in judging concepts involving unknown numbers and children made more accurate commutativity than associativity judgements. Children with conceptual profiles indicating a strong understanding of concepts applied to unknown numbers were more accurate at solving number‐word problems than those with a poor conceptual understanding. The findings suggest that an important mathematical development during the preschool years may be learning to appreciate addition concepts as general principles that apply when exact numbers are unknown. 相似文献
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33.
John DuBose Xinyu Lu Saurin Patel Shizhi Qian Sang Woo Joo Xiangchun Xuan 《Biomicrofluidics》2014,8(1)
Shape is an intrinsic marker of cell cycle, an important factor for identifying a bioparticle, and also a useful indicator of cell state for disease diagnostics. Therefore, shape can be a specific marker in label-free particle and cell separation for various chemical and biological applications. We demonstrate in this work a continuous-flow electrical sorting of spherical and peanut-shaped particles of similar volumes in an asymmetric double-spiral microchannel. It exploits curvature-induced dielectrophoresis to focus particles to a tight stream in the first spiral without any sheath flow and subsequently displace them to shape-dependent flow paths in the second spiral without any external force. We also develop a numerical model to simulate and understand this shape-based particle sorting in spiral microchannels. The predicted particle trajectories agree qualitatively with the experimental observation. 相似文献
34.
Chavan VU Durgawale PP Sayyed AK Sontakke AV Attar NR Patel SB Patil SR Nilakhe SD 《Indian journal of clinical biochemistry : IJCB》2011,26(3):283-289
Twenty-four hour urinary albumin excretion (UAE) is considered as gold standard method for albuminuria measurement, but collection
of 24-h urine is inconvenient. The aim of present study was to evaluate whether albumin: creatinine ratio (ACR) and urinary
albumin concentration (UAC) in different spot urine samples correlate or not with 24-h UAE for screening of microalbuminuria
in type 2 diabetic patients. We collected first morning void (FMV), random urine sample (RUS) and 24-h urine, separately on
consecutive days from 104 type 2 diabetic patients. ACR and UAC in each spot urine sample compared with 24-h UAE with regard
to Pearson correlation coefficient. Pearson’s correlation of albumin: creatinine ratio (ACR) with 24-h UAE was (r = 0.802 and 0.623) in first morning void (FMV) and random urine sample (RUS), respectively. Pearson’s correlation coefficient
of urinary albumin concentration (UAC) compared with 24-h UAE was (r = 0.943 and 0.920), in FMV and RUS, respectively, P < 0.01. Results revealed that values in first morning void (FMV) were better correlated with 24-h urinary albumin excretion
(UAE), than the values in random urine sample (RUS). We conclude that the first morning void (FMV) may be able to replace
24-h urine collection, preferably urinary albumin concentration (UAC) in the initial screening of microalbuminuria in diabetic
patients. 相似文献
35.
Vidya Akhileshwar Samir P. Patel Surendra S. Katyare 《Indian journal of clinical biochemistry : IJCB》2007,22(1):84-90
Studies were carried out to examine and compare the effects of alloxan-diabetes on reactive oxygen species (ROS) related parameters
in the heart from male and female rats. Effects of insulin treatment were also evaluated. The diabetic state severely compromised
the ROS defense mechanism in the cardiac tissue and the effects were more pronounced in the female than in the male rats.
There was several fold increase in the xanthine oxidase (XO) activity in general and the magnitude of increase was higher
in the females; insulin treatment resulted in further increase in the XO activity. The glucose-6-phosphate dehydrogenase (G6PDH)
and catalase activities decreased and the reduced glutathione (GSH) content in mitochondria was completely depleted in diabetic
state with significant decrease in the GSH levels in the post-mitochondrial fraction; the effect was more pronounced in the
females. The superoxide dismutase (SOD) and glutathione peroxidase (GPox) activities increased in the diabetic state to a
greater extent in male rats. Insulin treatment had restorative action only on some parameters. In conclusion, our results
suggest that diabetic state may further compromise the weak ROS defense systems in the heart thus initiating a lesion at the
level of mitochondria which ultimately leads to cardiomyopathy and the effects are especially more pronounced in the females.
Our results also pointed out that insulin treatment was ineffective in restoring ROS related parameters. 相似文献
36.
Paola Giuri Myriam Mariani Gustavo Crespi Dominique Francoz Walter Garcia-Fontes Raul Gonzales Karin Hoisl Alessandra Luzzi Lionel Nesta Önder Nomaler Pari Patel Bart Verspagen 《Research Policy》2007,36(8):1107-1127
Based on a survey of the inventors of 9017 European patented inventions, this paper provides new information about the characteristics of European inventors, the sources of their knowledge, the importance of formal and informal collaborations, the motivations to invent, and the actual use and economic value of the patents. 相似文献
37.
R.V. Patel 《Journal of The Franklin Institute》1984,318(2):123-141
This paper describes a computational method for solving the problem of eigenvalue assignment in a multi-input linear system. The given system is first reduced to an upper block Hessenberg form by means of orthogonal state coordinate transformations. It is then shown how a sequence of state feedback matrices and orthogonal state coordinate transformations can be applied to obtain a block triangular structure for the resulting state matrix, where the matrices on the diagonal are square matrices in upper Hessenberg form and of dimensions equal to the controllability indices of the multi-input system. Furthermore, the structure of the corresponding input matrix is such that the problem of eigenvalue assignment in the multi-input system can be reduced to several single-input eigenvalue assignment problems where the dimensions of the single-input systems are equal to the controllability indices of the multi-input system. 相似文献
38.
This paper reports two studies on comprehension of pharmaceutical texta containing pictorial and written instructions by mothers in rural Kenya. The subjects were asked to read and recall instructions for preparing and administering a solution for the treatment of dehydration due to diarrheal disease in children. A set of pictures describing the preparation procedure, together with written text instructions under two conditions, (a) original, as in the commercial product, and (b) revised, to include familiar terminology and explanations of some procedures, were presented to two groups of Kenyan mothers. The verbal protocols generated were transcribed and analyzed using propositional representation of instructional procedures.The results showed that mothers recalled the procedures for the preparation as in the pictures but not those presented in the written instructions. The written instructions were generally found to be difficult, with the original text being more difficult than the revised text. Any conflicting information between the written and pictorial instructions was resolved by selecting the familiar procedure. The information recalled from the revised text that was recalled was that which supported the procedures in the pictures. The results have implications for writing adequate pharmaceutical texts for users such that little room is left for misinterpretation. 相似文献
39.
40.
Callie Martin Mardis Dunham Samir H. Patel Susana Contreras‐Bloomdahl 《Psychology in the schools》2016,53(9):926-937
The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM‐5), requires that symptoms of ADHD must be developmentally inappropriate in order for an ADHD diagnosis to be considered. Because the DSM‐5 does not specifically outline procedure for determining developmental inappropriateness of behaviors, practitioners do not have guidance for making this consideration. To explore the relationship between mental age and behavior ratings of ADHD symptoms, the cognitive and behavioral data from 50 children who were evaluated in a school or clinic were compiled for this study. Cognitive ability scores were used to calculate mental age and behavior rating scores were then recalculated using the assessed mental age. Using the recalculated behavior ratings, scores based on mental age decreased significantly on the Attention Problems, Hyperactivity, and Atypicality scales of the BASC‐2. Additionally, as the discrepancy between mental and chronological age increased, larger differences in scores were found. 相似文献