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Amal Hussain Alajmi 《Journal of Mathematics Teacher Education》2009,12(4):263-283
Computational estimation has not yet established a place in the Kuwaiti national curriculum. An attempt was made to include
it during the early 1990s, but it was dropped by the Kuwaiti Ministry of Education because of the difficulties teachers had
teaching it. In an effort to provide guidance for reintroducing the concept into the curriculum, this study reports on mathematics
teachers’ understanding of the meaning of computational estimation and their views about its significance in the elementary
and middle school curricula in Kuwait. Data gathered from 59 elementary and middle schools teachers in Kuwait revealed that
more than 60% of teachers equate computational estimation with rounding. While two-thirds of the teachers viewed computational
estimation to be an important skill for daily life; only one-fifth (20%) saw it as important in mathematics education. More
than half of the teachers either disagreed with the idea of teaching computational estimation or only wanted to teach it in
limited situations. Most were concerned about the difficulty of learning computational estimation or feared that teaching
computational estimation would cause problems with students’ development of standard algorithms for determining an exact answer.
These findings reveal the challenge that mathematics educators face in introducing computational estimation into the mathematics
curriculum. In order for computational estimation to be taught in elementary and middle school classrooms, teachers need to
understand the concept and its value in education. Teacher education needs to focus on helping teachers better understand
the concept of computational estimation and appreciate its value for instruction. 相似文献
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B. Shailaja G. Jagadeesh Tajamul Hussain M. P. J. S. Anandaraj 《Indian journal of clinical biochemistry : IJCB》1996,11(2):165-167
With a view to gain an insight into the regulation of calcium activated neutral protease by its endogenous inhibitor, the inhibitor was quantitated in platelets and lymphocytes of Duchenne muscular dystrophy patients and controls by dot immunoblot procedure using polyclonal antibodies against the inhibitor. A two fold increase in inhibitor levels was observed in lymphocytes but no significant increase in inhibitor levels in platelets from Duchenne muscular dystrophy. These results suggest that different regulatory mechanisms of modulation of CANP operate in these two cell types in Duchenne muscular dystrophy. 相似文献
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This paper presents a class of time-frequency distributions (TFDs) characterized by time-lag kernels which are functions of time only. If the parameters of the time-only kernels are properly chosen, their corresponding TFDs, the T-distributions, are more efficient than their two-dimensional counterparts in terms of cross-terms suppression while keeping a high-energy concentration (resolution) around the IF law of non-stationary signals. The proposed class is a subclass of Cohen's Class of quadratic TFDs. We have shown that separable time-lag kernels should be lag-independent (or time-only) for best resolution. In addition, non-parametric amplitude estimation is possible directly from the T-distributions in case of FM signals, a property that is not verified by other TFDs. Two examples of the T-distributions are given and their performance is compared to other TFDs with numerical examples using synthetic and real-life signals. 相似文献
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P. Aruna Prabhavathi Tajamul Hussain G. N. Mallikarjuna Rao MP JS Anandaraj 《Indian journal of clinical biochemistry : IJCB》2002,17(1):94-98
The efficacy of two intragenic polymorphic markers of factor VIII gene has been examined in Andhra Pradesh population with
a view to confirm/revise the strategy for carrier detection that would be precise and economical. The haemophilia A carrier
was detected using Bcl I and Xba I polymorphic sites in intron 18 and 22 respectively. The cumulative efficiency of these
two sites for detection of carriers is 100% since all 15 families tested were informative for one of these polymorphisms,
thus confirming their usefulness for factor VIII gene mutations found in Andhra Pradesh. 相似文献
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Nazim HUSSAIN Hui LI Yu-xiao JIANG Zahra JABEEN Imran Haider SHAMSI Essa ALI Li-xi JIANG 《Journal of Zhejiang University. Science. B》2014,(2)
研究目的:生育酚是菜籽重要的品质指标,氮肥是影响作物生物学与籽粒产量最常用的肥料。这项研究旨在搞清楚氮肥种类与施量对油菜种子生育酚含量与组分的确切影响,以及这种影响在基因型之间的差异。创新要点:这篇论文研究了不同的氮肥种类(硝态氮与铵态氮)与低、中、高施用量对种子生育酚总量与组分的影响,并分析了其中的原因,为通过合理的氮肥施用方案配置,以达到最理想的菜籽生育酚含量或组分提供依据。研究方法:采用盆钵实验控制氮肥施量与流失的精准方法,五种基因型、二种氮肥种类、三档施量水平,三重复控制误差;尝试用气相色谱法检测菜籽生育酚含量的新方法。重要结论:尿素比硝酸氨更有利于菜籽总生育酚、阿尔法生育酚及伽马生育酚的有效形成;提高氮肥施量对于菜籽形成高含量的总生育酚与伽马生育酚非常有效,但对提高菜籽阿尔法生育酚含量的效果却不太明显。 相似文献
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Immunogenicity of formaldehyde and binary ethylenimine inactivated infectious bursal disease virus in broiler chicks 总被引：2，自引：2，他引：0
Habib M Hussain I Irshad H Yang ZZ Shuai JB Chen N 《Journal of Zhejiang University. Science. B》2006,7(8):660-664
Infectious bursal disease virus （IBDV） was inactivated by two different chemicals-formaldehyde and binary ethylenimine （BEI）. Formaldehyde was used at 0. 1% and 0.2%, while BEI was used at concentrations of 0.001 and 0.002 mol/L. These four vaccines were tested for their efficiency in generating humoral immune response in different groups of broiler chicks. Both BEI-inactivated vaccines gave relatively higher antibody titers and were almost twice as efficient as formaldehyde-inactivated ones. 相似文献