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1.
Research in Science Education - The purpose of this research is to investigate the effect of using argumentation and problem-based learning approaches on the development of environmentally...  相似文献   
2.
In this paper, we present a functional variable method for finding periodic wave and solitary wave solutions of complex nonlinear evolution equations in mathematical physics and engineering sciences. The proposed technique is tested on the generalized Zakharov equation and higher-order nonlinear Schrödinger equations. The method is straightforward and concise, and it can also be applied to other nonlinear evolution equations in applied mathematics.  相似文献   
3.
The initial time difference practical stability in terms of two measures has been investigated for nonlinear fractional differential equations in Caputo's sense and these properties have been unified with Lyapunov-like functions to establish a comparison result.  相似文献   
4.

Background:

The ultra-large von Willebrand factor (vWF) multimers are very active and must be degraded by ADAMTS13 for optimal activity. A severe functional deficiency of ADAMTS13 has been associated with thrombotic thrombocytopenic purpura. The correct interpretation of patient vWF and ADAMTS13 plasma levels requires an understanding of the biological variation associated with these analytes. In the present paper, we aimed to determine the biological variation of ADAMTS13 and vWF in human adults.

Materials and methods:

Blood samples were collected weekly from 19 healthy subjects for 5 consecutive weeks. vWF activity and antigenicity were determined using aggregometric and immunoturbidimetric methods. ADAMTS13 antigenicity and activity were determined by ELISA.

Results:

The within-subject biological variations for vWF activity and antigenicity were 8.06% and 14.37%, respectively, while the between-subject biological variations were 18.5% and 22.59%, respectively. The index of individuality for vWF activity was 0.44, while vWF antigenicity was 0.64. Similarly, ADAMTS13 activity and antigenicity within-subject biological variations were 12.73% and 9.75%, respectively, while between-subject biological variations were 9.63% and 6.28%, respectively. The ADAMTS13 indexes of individuality were 1.32 and 1.55, respectively.

Conclusion:

We report high biological variation and individuality in vWF antigenicity and activity levels. However, ADAMTS13 antigenicity and activity displayed high biological variation, but low individuality. Thus, population-based reference intervals may be useful for monitoring ADAMTS13 antigenicity and activity, but not for vWF, which displays high individuality. These findings should be considered when determining the reference interval and other clinical variables associated with ADAMTS13 and vWF levels.  相似文献   
5.

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   
6.
The purpose of the present study was to explore the relationships among Turkish elementary student teachers’ epistemological beliefs and moral reasoning, and to determine which types of epistemological beliefs elementary student teachers exhibit. The findings of the present study demonstrated that epistemological beliefs did not make a unique contribution to moral reasoning and student teachers’ epistemological beliefs developed as more or less independent beliefs. The factor analyses results suggest that multidimensional theory is more appropriate than unidimensional theory in explaining student teachers’ epistemological beliefs.  相似文献   
7.
Information Technology (IT) infrastructure integration and knowledge management (KM) share communal objectives e.g. to transform organisations into more effective and efficient, agile and innovative, and more responsive to market changes. Such an association when assimilates bona fide knowledge management philosophy, it offers the IT departments a headship opportunity for organisational transformation in correlation with the rest of the organisation. Despite more than a decade of active research and practice in this complex problem area, advocates still perceive that Local Government Authorities (LGAs) lack integrated IT infrastructures that have resulted in the generation of data inconsistencies and redundancies, inefficient knowledge exchange and reduction in service quality and delivery. In the recent years, several LGAs have implemented Enterprise Application Integration (EAI) solutions to integrate their IT infrastructure. However, on analysing the relevant research studies, it is noticeable that application of EAI has been practiced at a larger scale in the private domain but to limited scale in the public domain. The shortage of such research studies presents a knowledge gap that needs to be endorsed. This research adapts a Revised Model for Integration Layers (REAL). By adapting to this model, it is exemplified that EAI achieves integration at five layers namely: connectivity, transportation, transformation, process integration and knowledge integration. The methodology for validating this model included a qualitative analysis of data gathered from formal interviews, observations and archive documents guided by initial conceptual observations from the literature. The findings indicate that cases leading to data inconsistencies and replication can be prevented by integrating knowledge through EAI.  相似文献   
8.
Education and Information Technologies - The technological developments of the twenty-first century have enabled the emergence of alternative teaching-learning models and instructional tools. One...  相似文献   
9.
Publishers will usually make decisions based on their experience and knowledge in book publishing. However, there are risks of losses as markets can be unpredictable. Now, with the availability of various online social platforms, “crowdsourcing” is being used by publishers and authors to gather new ideas and innovations. This article will analyze how the crowdsourcing platform is used by industry players to attract active participation from the public, especially in the title development process. Publishers or authors also need to understand which platform is appropriate and how to use the platforms as a marketing communication tool. The netnography approach will be used to gather and analyze the data related to the specific subject area of the study, including literature review and online observation. Based on our observations, platforms such Wattpad and Ilham Karangkraf are popular among Malaysian authors and publishers, and had been used to get crowd engagement as well as to communicate with readers. With it, sometimes a work that has many readers or followers will be published.  相似文献   
10.
The objective of this research is to investigate the effects of simulations based on conceptual change conditions (CCS) and traditional confirmatory simulations (TCS) on pre-service elementary school teachers’ understanding of direct current electric circuits. The data was collected from a sample consisting of 89 students; 48 students in the experimental group who were taught simulations based on CCS, and 41 students in control group who followed the TCS. Subjects in both groups used open source software (Qucs) to simulate electric circuits. All students were administered Electric Circuits Concepts Test (DIRECT), Science Process Skills Test, Physics Attitude Scale, and Computer Attitude Scale before the treatment. Pre-test analyses revealed that there is no significant difference between experimental and control groups in terms of understanding of direct current electricity. After completing 3 weeks treatment, all students received the DIRECT again as a post-test. Analysis of covariance was used. Science process skills and attitudes toward computers were taken as covariates. The results showed that the conceptual change based simulations caused significantly better acquisition of conceptual change of direct current electricity concepts than the confirmatory simulation. While science process skills and attitudes towards computer made significant contributions to the variations in achievement, gender differences and interactions between gender and treatment did not. Eleven weeks later, the DIRECT was reapplied to the students in both groups. Eleven weeks delayed post-test results showed that the experimental group outperformed the control group in understanding of direct current electric concepts.  相似文献   
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