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排序方式: 共有266条查询结果,搜索用时 375 毫秒
31.
Tiwari AK Mahdi AA Zahra F Chandyan S Srivastava VK Negi MP 《Indian journal of clinical biochemistry : IJCB》2010,25(4):411-418
The present study was conducted to investigate the oxidant–antioxidant status in iron deficient pregnant anemic women. One
hundred thirty pregnant women with iron deficiency anemia (IDA) were divided into three groups, namely mild (50), moderate
(50) and severe (30) anemic along with pregnant healthy women as controls (50). The complete blood count, plasma lipid peroxidation
products, enzymatic and non-enzymatic antioxidants were measured according to respective protocols. The levels of complete
blood count, iron, ferritin along with antioxidant enzymes namely catalase, superoxide dismutase, glutathione peroxidase,
glutathione reductase and reduced glutathione were significantly reduced in all IDA groups. However, the level of oxidized
glutathione, lipid peroxides, protein carbonyls, conjugated dienes were found significantly increased in all anemic patients.
Antioxidant vitamins, namely C, E and A were also found significantly decreased in IDA patients. On the basis of our results,
it may be concluded that IDA tends to increase the pro-oxidant components, which may result in various complications including
peroxidation of vital body molecules resulting in increased risk for pregnant women as well as fetus. 相似文献
32.
This paper addresses the filtering problem for the one-sided Lipschitz nonlinear systems under measurement delays and disturbances using a generalized observer. A generalized architecture for filtering of the one-sided Lipschitz nonlinear systems with output delays is explored, which exhibits diverging manifolds, namely, the conventional static-gain filter and the dynamical filter, and can be employed to render robust stability of the filtering error dynamics. A matrix inequality based framework is obtained by employing a Lyapunov?Krasovskii (LK) functional, whose derivative is exploited through Jensen's inequality, one-sided Lipschitz condition, quadratic inner-boundedness inequality and range of the measurement delay, resulting into L2 stability for the filtering error system. Generalized filter design for the Lipschitz nonlinear systems with delayed outputs and specific results for the delay-dependent and delay-rate-independent filtering schemes for the one-sided Lipschitz nonlinear systems are deduced from the proposed approach. Convex optimization techniques are employed to achieve a solution for the nonlinear constraints through linear matrix inequalities by employing cone complementary linearization approach. Illustrative numerical examples to demonstrate the effectiveness of proposed method are provided. 相似文献
33.
Susan Bruce Zayyad Muhammad 《International Journal of Disability, Development & Education》2009,56(3):229-246
This article presents a review of the literature on object permanence with an emphasis on research on children with severe disabilities. Object permanence is the realisation that objects continue to exist in time and place even when they are no longer visible. This understanding is achieved across Stages IV(VI of Piaget’s Sensorimotor Period. Children with intellectual disability, physical disabilities, blindness, and autism develop object permanence in a similar sequence although at a slower rate than children without disabilities. Challenges with regulation make it difficult for children with autism to demonstrate object permanence knowledge in Stage VI tasks. There is ample evidence that children with severe disabilities benefit from direct and systematic instruction of object permanence. Assessment‐based instruction, establishment of visual attention, consideration of the characteristics of the object to be hidden (including the impact on differential attention), repeated naming of the object, individually appropriate prompting procedures, and direct reinforcement have been found to support mastery of object permanence in children with disabilities. 相似文献
34.
Sajid Sheikh Muhammad Muhammad Aurangzeb Imtiaz Tarique 《美中教育评论》2009,6(8):62-67
In this paper, the growth of the telecommunication sector in Pakistan and consequent development in the related professional education is studied. The widening gap between the telecommunication industry and associated education sector is identified. The higher educational programs in Pakistan have grown very rapidly to meet the needs of the explosive growth in the telecommunications' engineering sector but this growth is not in synchronization with the requirements of the industry due to non-existence of collaboration and co-operation between the two. The professional education in telecommunication in Pakistan and the higher educational degree programs are very precisely focused on producing quality graduates with refined technical and mathematical skills While the telecom sector in Pakistan is in principle a service provider and a consumer market that mainly requires engineers for operation and maintenance related activities. As such the skills imparted by the education sector are rarely utilized, which results in dissatisfaction among the telecommunications' engineers. A survey of both the telecommunication sector and the academia has been conducted along with detailed discussions to explore the reasons for this ever-increasing gap, ways and means to arrest this trend and future course of action for the academia and the telecom sector to develop. A study related to other emerging technical fields like computer science has also been made for the comparison. On the basis of this extensive exercise outlined above, measures have been suggested to bridge the gap between the education and the industrial needs of the telecom sector. By adopting these measures not only our education sector will become more beneficial to the industry, but the industry would also get the advantage of immense potential of young graduates and the academic research. 相似文献
35.
Safia Abbas Hajime Sawamura 《美中教育评论》2010,7(9):58-67
This paper presents the development of an Argument-Learning System (ALES). The idea is based on the AIF (argumentation interchange format) ontology using "Walton theory". ALES uses different mining techniques to manage a highly structured arguments repository. This repository was designed, developed and implemented by the authors. The aim is to extend the previous framework proposed by developing an intelligent tutoring environment for argument learning that aims to: (1) guide the students during argument learning; (2) aid in improving the students' argument skills; and (3) offer an argument classifier agent that retrieves the most relevant results to the subject of search. This paper focuses on the environment development specifying the status of each of the constituent modules. 相似文献
36.
The management of intellectual capital (IC) resources increases organizational value creation capacities. The aim of this study is to present an algorithm for analysing IC management with an emphasis on the recognition and modelling of growth mechanisms for strategic resources. Intensive interactions among different tangible and intangible assets turn organizations into complex systems of highly interrelated resources; therefore, a systems approach is adopted, and a causal loop diagram is used to model resource interaction feedback structures. The development and analysis of the resource interactions model is explained through a practical algorithm that reveals different dimensions of resource deployment, including the potential value of resources, utilization of resources in key business processes, and mechanisms responsible for the sustained growth of strategic resources. The proposed algorithm was used to examine a telecommunication company. We show that there are no growth mechanisms for certain strategic resources. To activate the growth of such strategic resources, several feedback loops are recognized and related initiatives are proposed. 相似文献
37.
This study introduces measures to identify resonant (concentration of energy in a single or a few frequencies) or unfavorable earthquake ground motions. Probabilistic measures based on the entropy rate and the geometric properties of the power spectral density function (PSDF) of the ground acceleration are developed first. Subsequently, deterministic measures for the frequency content of the ground acceleration are also developed. These measures are then used for identifying resonance and criticality in stochastic earthquake models and 110 acceleration records measured at rock, stiff, medium and soft soil sites. The unfavorable earthquake record for a given structure is defined as the record having a narrow frequency content and dominant frequency close to the structure fundamental natural frequency. Accordingly, the measures developed in this study may provide a basis for selecting records that are capable of producing the highest structural response. Numerical verifications are provided on damage caused to structures by identified resonant records. 相似文献
38.
Moslem Bahmani Abbas Bahram Jed A Diekfuss Saeed Arsham 《Journal of sports sciences》2013,31(20):2318-2330
ABSTRACTThe aims of this study were to (1) to explore attentional strategies in expert judo players and (2) investigate how attentional focus affects performance effectiveness and perceptions of workload in expert judo players during real competitions. Fourteen expert male judo players participated in the study. A simulated recall method was used following participants’ competition to explore contents of attention qualitatively. The data analysis process for the qualitative portion of the study was an iterative process between inductive and deductive analyses. Quantitative analyses of performance outcomes and workload were then associated with the qualitative findings. Qualitative results revealed that the focus of attention was dynamic and complex, with technical aspects of the movements as the highest identified focus. Quantitative analyses revealed that reporting a lower quantity of attentional cues and higher percentage of focus on opponent resulted in higher performance effectiveness and less perceptions of workload. This study indicates that cognitive control and automaticity may work in a synergistic manner for successful skill execution in expert performance. 相似文献
39.
local government authorities (LGAs) are organised around operational structures with business processes spanning within departments and across other government organisations. In such an organisational setting, the harmonisation of Information Technology (IT) operations, integration of cross-departmental processes and the underlying Information Systems (IS) signifies a challenge in delivering integrated services. This paper attempts to explore enterprise application integration (EAI) adoption in the UK local government authorities (LGAs). Despite the hype of EAI adoption in private domain, its application in LGAs is inadequate as there is a lack of adoption models/frameworks that can be used by the public sector. The context of the study is to consider the transformation of IT infrastructure management and operations with EAI technologies. The empirical findings, generated through a detailed case analysis, manifestly exemplify that EAI predominantly acts as a ‘back-office’ technology that facilitates operations by developing a flexible and maintainable integrated IT infrastructure. Our proposed framework is believed to be imperative and unique as it provides a more systematic way to examine the adoption of integration technologies, extends the established norms for EAI adoption by utilising a prioritisation technique to classify the importance of factors. The contribution of the research extends the literature on EAI and identifies theoretical and practical opportunities that facilitate LGAs in their decision-making process to produce more robust proposals for EAI adoption. 相似文献
40.
In this paper, a novel approach for the design of an indirect adaptive fuzzy output tracking excitation control of power system generators is proposed. The method is developed based on the concept of differentially flat systems through which the nonlinear system can be written in canonical form. The flatness-based adaptive fuzzy control methodology is used to design the excitation control signal of a single machine power system in order to track a reference trajectory for the generator angle. The considered power system can be written in the canonical form and the resulting excitation control signal is shown to be nonlinear. In case of unknown power system parameters due to abnormalities, the nonlinear functions appearing in the control signal are approximated using adaptive fuzzy systems. Simulation results show that the proposed controller can enhance the transient stability of the power system under a three-phase to ground fault occurring near the generator terminals. 相似文献