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91.
The extraordinary romance and thrilling adventure associated with the tale of wootz steel shows how Indian metallurgists were
the world leaders in antiquity in the manufacture of this legendary high-grade steel. In many ways this material was brought
to global attention by the writings of Cyril Stanley Smith. Modern metallurgy and materials science rest on the foundation
built by the study of this steel during the past three centuries. 相似文献
92.
Orthographic spelling is a major difficulty in German-speaking children with dyslexia. The aim of the present study was to
evaluate the effectiveness of an orthographic spelling training in spelling-disabled students (grade 5 and 6). In study 1,
ten children (treatment group) received 15 individually administered weekly intervention sessions (60 min each). A control
group (n = 4) did not receive any intervention. In study 2, orthographic spelling training was provided to a larger sample consisting
of a treatment group (n = 13) and a delayed treatment control group (n = 14). The main criterion of spelling improvement was analyzed using an integrated dataset from both studies. Repeated-measures
analysis of variance revealed that gains in spelling were significantly greater in the treatment group than in the control
group. Statistical analyses also showed significant improvements in reading (study 1) and in a measure of participants’ knowledge
of orthographic spelling rules (study 2). The findings indicate that an orthographic spelling training enhances reading and
spelling ability as well as orthographic knowledge in spelling-disabled children learning to spell a transparent language
like German. 相似文献
93.
Charys M. Martin Victoria A. Roach Ngan Nguyen Charles L. Rice Timothy D. Wilson 《Anatomical sciences education》2013,6(6):393-403
The use of three‐dimensional (3D) models for education, pre‐operative assessment, presurgical planning, and measurement have become more prevalent. With the increase in prevalence of 3D models there has also been an increase in 3D reconstructive software programs that are used to create these models. These software programs differ in reconstruction concepts, operating system requirements, user features, cost, and no one program has emerged as the standard. The purpose of this study was to conduct a systematic comparison of three widely available 3D reconstructive software programs, Amira®, OsiriX, and Mimics®, with respect to the software's ability to be used in two broad themes: morphometric research and education to translate morphological knowledge. Cost, system requirements, and inherent features of each program were compared. A novel concept selection tool, a decision matrix, was used to objectify comparisons of usability of the interface, quality of the output, and efficiency of the tools. Findings indicate that Mimics was the best‐suited program for construction of 3D anatomical models and morphometric analysis, but for creating a learning tool the results were less clear. OsiriX was very user‐friendly; however, it had limited capabilities. Conversely, although Amira had endless potential and could create complex dynamic videos, it had a challenging interface. These results provide a resource for morphometric researchers and educators to assist the selection of appropriate reconstruction programs when starting a new 3D modeling project. Anat Sci Educ 6: 393–403. © 2013 American Association of Anatomists. 相似文献
94.
Two groups of 4.5–5.5 year old children in their first year at school were examined; one taught by a whole word teaching method and one taught by a mixed whole word and phonological teaching method. The children were given a test to investigate their reading of normal words. The results of this test were subjected to a detailed error analysis and the two groups were examined in order to see if there were differences in the reading strategies they used. No evidence was found counter to the assumption that reading begins with a logographic stage. However, it was found that teaching method was having a significant impact on the reading strategies which the children adopted. In addition it was found that a number of children from the whole school appeared to exhibit letter by letter reading. This suggests that letter by letter dyslexia might in part be an extreme form of a strategy used by normal readers. 相似文献
95.
Walter P. Vispoel Thomas R. Rocklin Tianyou Wang Timothy Bleiler 《Journal of Educational Measurement》1999,36(2):141-157
Part of the controversy about allowing examinees to review and change answers to previous items on computerized adaptive tests (CATs) centers on a strategy for obtaining positively biased ability estimates attributed to Wainer (1993) in which examinees intentionally answer items incorrectly before review and to the best of their abilities upon review. Our results, based on both simulated and live testing data, showed that there were instances in which the Wainer strategy yielded inflated ability estimates as well as instances in which it yielded deflated ability estimates. The success of the strategy in inflating ability estimates depended on the ability estimation method used (maximum likelihood versus Bayesian), the examinee's true ability level, the standard error of the ability estimate, the examinee's ability to implement the strategy, and the type of decision made from the ability estimate. We discuss approaches to dealing with the Wainer strategy in operational CAT settings. 相似文献
96.
Luciano Floridi argues that every existing entity is deserving of at least minimal moral respect in virtue of having intrinsic value qua information object. In this essay, I attempt a comprehensive assessment of this important view as well as the arguments Floridi offers in support of it. I conclude both that the arguments are insufficient and that the thesis itself is substantively implausible from the standpoint of ordinary intuitions. 相似文献
97.
Acoustic trapping of minute bead amounts against fluid flow allows for easy automation of multiple assay steps, using a convenient aspirate/dispense format. Here, a method based on acoustic trapping that allows sample preparation for immuno-matrix-assisted laser desorption/ionization mass spectrometry using only half a million 2.8 μm antibody covered beads is presented. The acoustic trapping is done in 200 × 2000 μm2 glass capillaries and provides highly efficient binding and washing conditions, as shown by complete removal of detergents and sample processing times of 5-10 min. The versatility of the method is demonstrated using an antibody against Angiotensin I (Ang I), a peptide hormone involved in hypotension. Using this model system, the acoustic trapping was efficient in enriching Angiotensin at 400 pM spiked in plasma samples. 相似文献
98.
?erif Ercan Mustafa ?al??kan Erhan Koptur 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2014,24(3):391-395
Introduction:
There are a number of pre-analytical and analytical factors, which cause false results in the complete blood count. The present case identifies cold agglutinins as the cause for the mismatch between hematocrit and hemoglobin values.Materials and methods:
70-year old female patient had a history of cerebrovascular diseases and rheumatoid arthritis. During routine laboratory examination, the patient had normal leukocyte and platelet counts; however, the hemoglobin (Hb: 105 g/L) and hematocrit (HCT: 0.214 L/L) results were discordant. Hemolysis, lipemia and cold agglutinin were evaluated as possible reasons for the mismatch between hematocrit and hemoglobin values.Results:
First blood sample was slightly hemolysed. Redrawn sample without hemolysis or lipemia was analyzed but the mismatch became even more distinct (Hb: 104 g/L and HCT: 0.08 L/L). In this sample, the titration of the cold agglutinin was determined and found to be positive at 1:64 dilution ratios. After an incubation of the sample at 37°C for 2 hours, reversibility of agglutination was observed.Conclusion:
We conclude that cold agglutinins may interfere with the analysis of erythrocyte and erythrocyte-related parameters (HCT, MCV, MCH and MCHC); however, Hb, leukocyte and platelet counts are not affected. 相似文献99.
A seven channel polystyrene (PS) microchip has been constructed using a micromilling machine and a high-temperature assembling. Protein A (PA) has been immobilized by a passive sorption on the microchannel walls. Two bioaffinity assays with human immunoglobulin G (hIgG) as a ligand have been carried out. (i) PA as the receptor and fluorescently labeled hIgG (FITC-hIgG) as the ligand, (ii) PA as the receptor with hIgG as the quantified ligand and fluorescently labeled goat anti-human IgG (FITC-gIgG) as the secondary ligand. One incubation step of the assays took only 5 min instead of hours typical for enzyme-linked immunosorbent assay applications. Calibration curves of the dependence of a fluorescence signal on the hIgG concentration in a sample have been obtained in one step due to a parallel arrangement of microchannels. A mathematical model of the PA-FITC-hIgG complex formation in the chip has been developed. The values of the kinetic constant of the PA-FITC-hIgG binding (kon=5.5 m3 mol−1 s−1) and the equilibrium dissociation constant of the formed complex (Kd≤3×10−6 mol m−3) have been obtained by fitting to experimental data. The proposed microchip enables fast evaluation of kinetic and equilibrium constants of ligand-receptor bioaffinity pairs and the ligand quantification. As the use of microfluidic chips for immunoassays is often limited by price, we used procedures and chemicals that allow for an inexpensive construction and operation of the microdevice, e.g., temperature assembling as a fabrication technique, detection via an ordinary digital camera, nonspecific polystyrene as a substrate, passive sorption of biomolecules as an immobilization technique, etc. 相似文献
100.
Adrijana Doroti? Dragana Anton?i? Vanja Radi?i? Biljak Dara Nedi? Andjelo Beleti? 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2015,25(3):393-400