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Children's early literacy experiences are critical, yet it remains unclear whether memories of early reading instruction continue to be associated with reading habits into adulthood. We examined the association between recollections of reading experiences and present-day reading habits in an adult population. University students responded in writing to three open-ended prompts asking about their memories of reading during early childhood, elementary school and high school. They also completed two questionnaires inquiring about reading enjoyment and frequency in elementary school and high school. For the concurrent measures of reading, participants described their current reading habits in an open-ended prompt and completed an author recognition test. Results showed positive links between favourable memories of reading during elementary and high school years and present-day reading habits. Conversely, unfavourable memories during high school were associated with unenthusiastic present-day reading habits. We found that reading instruction in school forms long-lasting memories, and these memories are linked in meaningful ways with print exposure during adulthood. 相似文献
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The physics behind the game of billiards is rather well understood as is our grasp of classical mechanics. We present here a mathematical explanation of why slice shots are more difficult than direct shots. Despite a large number of treatises dedicated to the study of physics of billiards, it appears that the simple explanation has escaped our attention until now. We show that high impact-parameter shots impart a larger angular spread to the object ball, compared to head-on shots. The effect can be understood in terms of a non-linear relationship between the impact parameter and the scattering angle, and the fact that a real-world pool player does not have a perfect cue ball control; in other words, the impact parameter distribution is not a delta function, but has a finite spread. To keep the mathematics simple and not to obscure the underlying physical principles our treatment ignores the ball’s spin, friction, and other well-known effects in the game of pool. 相似文献
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Maryam Farahnak Zarabi Ali Farhangi Samaneh Khademi Mazdeh Zahra Ansarian Davod Zare Mohammad Reza Mehrabi Azim Akbarzadeh 《Indian journal of clinical biochemistry : IJCB》2014,29(2):154-160
Carboxylate-modified gold nanoparticles (GNPs) were synthesized in a simple one-step process based on the reduction of tetrachloroauric acid by aspartic acid in water. GNPs were identified by UV–Vis spectroscopy, dynamic light scattering (DLS) and transmission electron microscopy. Conjugation of protein molecules with functionalized nanoparticles was performed through electrostatic interaction. The GNP–protein conjugates were characterized by gel electrophoresis. The interaction between functionalized GNPs and protein molecules lead to conformational transition of protein structure after conjugation of protein with GNPs. This process was investigated by fluorescence spectroscopy and circular dichroism spectroscopy. 相似文献
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Azim Akbarzadeh Dariush Norouzian Ali Farhangi Mohammad Reza Mehrabi Shirin Jamshidi Davood Zare Morvarid Shafiei 《Indian journal of clinical biochemistry : IJCB》2008,23(1):57-61
Flow cytometry has been employed as a method to study homogeneity of isolated islet subpopulations. After collagenase digestion
of rat pancreas and elutriation of tissue fragments, islets were isolated and dissociated, and cells were analyzed and sorted
according to their low forward angle light scattering properties by using automated flow cytometry. A standardized procedure
was developed for the preparation of rat islet cell grafts for purification of islet cells. In this process, after collagenase
digestion of pancreas, islets were isolated, dissociated, identification by dithizone method and then with enzymatic procedure
by DNase and trypsin, the islet cells changed into single cells and beta cells were identified by immunofluorescence method
and then assayed by flow cytometry. Methods have been developed for the preparation of suspension of viable rat pancreatic
islet cells and their analysis and sorting in the fluorescence activated cell sorter (FACC IV, Becton Dickinson, Sunnyvale,
Ca). Flow cytometry of these cells indicated that there were 91% of beta cells in cell suspension. Most of the exocrine particles
were lost during digestion. Purified endocrine islet cell grafts were prepared by pure beta-cells, without endocrine non-beta
cells. The purified aggregates were devoid of endocrine non-beta cells and damaged cells. 相似文献
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The interaction of two identical polar neutral molecules is modeled by two equal but oppositely charged point particles at a fixed distance of separation. The total Coulomb potential energy of this system is calculated as a function of this distance, x, and the distance, y, between their centers of mass. We find that when the y/x ratio is less than about 3.1619, the linear configuration has the lower energy, whereas when this ratio exceeds 3.1619, a stacked structure is more stable. Interestingly, when two real polar molecules, such as HF interact, neither of these structures are formed. It is ‘hydrogen bonded’. The NaF dimer on the other hand, has a global minimum as stacked structure at a y/x ratio of about 1, significantly smaller than 3.1619! 相似文献
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