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71.
Gillian U. Bayne 《Learning Environments Research》2012,15(2):231-250
This research is distinctive in that a mixed-methods approach, employing both cogenerative dialogues and student responses from the Constructivist Learning Environment Survey (CLES), was used to help to understand 9th grade urban students?? experiences in their biochemistry class in New York City. Factor analyses of student responses demonstrated that empirically there were four robust scales rather than five. Qualitative analyses, using cogenerative dialogues and informal interviewing, demonstrated that more adaptable forms of teaching, learning and assessing could support a variety of students. Shared with students, the contents of the CLES and cogenerative dialogues created opportunities for understanding ontologies and helped to create, access and appropriate resources that assist in bringing about success in the science classroom. 相似文献
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Chemical and isotope characterization of lead finds at the Santa Barbara nuraghe (Bauladu, Sardinia)
Twenty lead finds, unearthed in Late Bronze–Early Iron Age levels at the Santa Barbara nuraghe situated at Bauladu in Sardinia (Italy), have been examined. Their chemical composition has been determined using the ICP-MS plasma-mass technique (Cu, Fe, As, Ag, Sn, Sb, Bi, Zn, Cs, Tl, Mo, Cd, In, Te, W, Th, U, Li, Se). Lead isotope ratios (208/206, 207/206, 206/204) have also been determined. The results are discussed in relation to the mineral source and some aspects of the metal extraction processes. The finds are composed of high purity lead obtained using a smelting at low temperature. Based on the isotope ratios it has been possible to establish that the metal originated from Sardinian ore deposits type. 相似文献
74.
Ho Tak U Kevin 《Educational Media International》2013,50(4):264-265
Abstract Integrated Services Digital Network (ISDN) is available today in Macau and has been since 1997. It is emerging as a mainstream telecommunications network that will serve a wide variety of users’ needs. It has improved service capabilities, reduced costs and improved productivity for Macau organizations, both large and small. The following are short notes on possible uses. 相似文献
75.
Miraca U.M. Gross 《Roeper Review》2013,35(4):189-194
Educators often fail to recognize that the intellectually gifted differ from their age peers in their social and emotional development as much as in their intellectual and academic characteristics. A dilemma peculiar to gifted youth arises through the interaction of the psychosocial drives towards intimacy and achievement, which complement each other in students of average ability, but which place the gifted student in a forced‐choice situation. If the gifted child chooses to satisfy the drive for excellence he or she must risk forfeiting the attainment of intimacy with age peers; if the choice is intimacy, the gifted may be forced into a pattern of systematic and deliberate underachievement to retain membership in the social group. Homogeneous grouping of gifted students is suggested as a partial solution to this dilemma. 相似文献
76.
We describe a case of poorly differentiated adenocarcinoma of stomach, which did not present typical symptoms of gastrointestinal
malignancy on first visit. The patient, a 62 year old smoker presented with shortness of breathe and pain in right lumbar
region with no history of fever. Bone scans revealed multiple hot spots in skull, sternum, lumbar vertebrae and both iliac
crests. A series of tumor markers were ordered which include PSA, CEA, CA19.9, CA 72.4 and AFP. Serum PSA and AFP concentrations
were within normal range. Serum CEA and CA 72.4 were raised significantly. Markedly elevated levels of serum CA19.9 were found
(>45000 U/ml) in this patient. CT chest and bronchoscopic examination ruled out the possibility of cancer lung. Upper GI tract
endoscopy was done to find out lesion in GI tract. An ulcerative lesion was found in lesser curvature of stomach. Histopathological
examination of endoscopic biopsy revealed a poorly differentiated adenocarcinoma of stomach. An unusually high serum CA19.9
(>45000U/ml) in case of gastric carcinoma has not been reported earlier. 相似文献
77.
The aim of this study was to investigate the effect of pre-induced inspiratory muscle fatigue (IMF) on race-paced swimming and acid-base status. Twenty-one collegiate swimmers performed two discontinuous 400-m race-paced swims on separate days, with (IMF trial) and without (control trial) pre-induced IMF. Swimming characteristics, inspiratory and expiratory mouth pressures, and blood parameters were recorded. IMF and expiratory muscle fatigue (P < 0.05) were evident after both trials and swimming time was slower (P < 0.05) from 150-m following IMF inducement. Pre-induced IMF increased pH before the swim (P < 0.01) and reduced bicarbonate (P < 0.05) and the pressure of carbon dioxide (PCO2) (P < 0.05). pH (P < 0.05), bicarbonate (P < 0.01) and PCO2 (P < 0.05) were lower during swimming in the IMF trial. Blood lactate was similar before both trials (P > 0.05) but was higher (P < 0.01) in the IMF trial after swimming. Pre-induced IMF induced respiratory alkalosis, reduced bicarbonate buffering capacity and slowed swimming speed. Pre-induced and propulsion-induced IMF reflected metabolic acidosis arising from dual role breathing and propulsion muscle fatigue. 相似文献
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