3,883 research outputs found
JUMPS IN DIFFERENT LEVELS OF WATER: AN OPTIMAL ENVIRONMENT TO JUMP ON LAND
The purpose of this study was to compare rate of force development (RFD) and rate of impact force (RIF) among on-land and in different levels of water jumps. Fourteen male participants were recruited in this study. Participants carried out the testing on land first and followed by testing in knee-high (LOW), trochanter major high (MID), and nasal-high (HIGH) of water. In each condition, participants performed 3 countermovement jumps (CMJ) separated by 15 sec rest. RFD and RIF were calculated. A repeated measure ANOVA was used for assessing the differences of variables among different conditions. The results showed that RFD for LOW is significantly lower than the others, and loading impact on-land is significantly higher than the others. Jumping in MID and HIGH are optimal levels of water for jumps training
Utilization of Intelligent Tutoring System (ITS) in mathematics learning
Intelligent Tutoring Systems (ITS) represent some of the knowledge and reasoning of good oneto-one human tutors, and consequently are able to coach students in a more detailed way as compared to the Computer Assisted Instructions (CAI) packages. Canfield (2001) defines ITS as a system that is able to diagnose and adapt to student's knowledge and skills. According to Canfield, ITS is able to provide precise feedbacks when mistakes are made and able to present
new topics when the student is ready to learn. ITS is part of a new breed of instructional computer programs. This paper discusses the benefits of using an ITS as complement to the use CAI materials such as the courseware in promoting the learning of mathematics. Benefits of using an ITS have been proven in aspects such as generating useful feedbacks to students in learning mathematic, assisting learning of higher order subject matter and cultivating higher order skills, offering a learning environment that motivates learners, giving useful instant feedback to
learners, and providing positive effects on student’s achievement
The effect of an intelligent tutoring system (ITS) on student achievement in algebraic expression.
In this experimental study, use of Computer Assisted Instruction (CAI) followed by use of an Intelligent Tutoring System (CAI+ITS) was compared to the use of CAI (CAI only) in tutoring students on the topic of Algebraic Expression. Two groups of students participated in the study. One group of 32 students studied algebraic expression in a CAI learning environment, while the other group of 30 students was in a CAI and ITS (CAI+ITS) environment. Before the experimental treatment began, subjects were given a pre-test on algebraic expression. A posttest was also given at the end of the study. The experimental treatment was administered in eight sessions with one hour per session. For the first stage of the
study, both groups of subjects studied algebraic expression in a CAI environment. In the second stage, subjects from the CAI group continued with a tutoring session using the drill and practice section of the CAI package, whereas subjects from the CAI+ITS environment continued their learning using the ITS tutorial. The results of the study showed that there was a significant difference in the students’ achievement in algebraic expression between students who learned with CAI+ITS and who learned with CAI only as the delivery system. The findings of the study
indicated that CAI+ITS was more effective in helping students learn algebraic expression as compared to using CAI alone. This study suggests that educators and software developers should focus on the development of ITS based learning tools or integrate ITS elements in courseware development rather than developing a mere CAI tool
Recommended from our members
Probing the Electrostatic and Steric Requirements for Substrate Binding in Human Platelet-Type 12-Lipoxygenase.
Human platelet ALOX12 (hALOX12 or h12-LOX) has been implicated in a variety of human diseases. The present study investigates the active site of hALOX12 to more thoroughly understand how it positions the substrate and achieves nearly perfect regio- and stereospecificities (i.e., 100 ± 5% of the 12(S)-hydroperoxide product), utilizing site-directed mutagenesis. Specifically, we have determined that Arg402 is not as important in substrate binding as previously seen for hALOX15 but that His596 may play a role in anchoring the carboxy terminal of the arachidonic acid during catalysis. In addition, Phe414 creates a π-stacking interaction with a double bond of arachidonic acid (Δ11), and Ala417/Val418 define the bottom of the cavity. However, the influence of Ala417/Val418 on the profile is markedly less for hALOX12 than that seen in hALOX15. Mutating these two residues to larger amino acids (Ala417Ile/Val418Met) only increased the generation of 15-HpETE by 24 ± 2%, but conversely, smaller residues at these positions converted hALOX15 to almost 100% hALOX12 reactivity [Gan et al. (1996) J. Biol. Chem. 271, 25412-25418]. However, we were able to increase 15-HpETE to 46 ± 3% by restricting the width of the active site with the Ala417Ile/Val418Met/Ser594Thr mutation, indicating both depth and width of the active site are important. Finally, residue Leu407 is shown to play a critical role in positioning the substrate correctly, as seen by the increase of 15-HpETE to 21 ± 1% for the single Leu407Gly mutant. These results outline critical differences between the active site requirements of hALOX12 relative to hALOX15 and explain both their product specificity and inhibitory differences
The Influence of Social Capital and Guanxi on Organizational Learning and Innovation in SMEs.
Literatures of learning in organisations have discovered social capital could enrich the information and knowledge acquisition for organisational development. Typically social capital is taken as the resource which could dominate the volume of external knowledge; and the relevant discussions also mainly concentrate their advantage on external interactions. In this thesis, I turn the emphasis to internal networks. In the relevant researches of organisational learning, they have pointed out the significant influences of power, labour division and internal/departmental boundaries on knowledge sharing and learning interactions. Social capital, which is existed within and between group networks, could affect their organisational learning. Thus, in this thesis, I am going to seek the contributions on the studies of organisational learning and social capital by demonstrating the effect of social capital on knowledge transfer and learning ability, with the emphasis of internal social networks. In order to present the influences of social capital on collective learning by comparing different social networks, I provide the evidences which were collected in family and non-family businesses. They are allocated on smaller IT Industry in Taiwan. Family businesses and non-family businesses have different social interactions; IT industry in Taiwan is a significant sector with intensive knowledge communication. They therefore became the researched groups which could facilitate the study. This thesis will develop the following topics: 1) the effect and development of social capital and guanxi on internal social interactions and collective learning; 2) the comparison of different social networks through the data in family and non-family businesses; and 3) the efficiency of learning and innovation under different social networks. I present the comprehensive discussions between social capital and collective learning, in which it consists of the contribution on the development of social capital theory and also the effect of social networks on collective learning. Besides, I add the concept of guanxi to explain and discover some specific social interactions embedded in Chinese/Taiwanese culture. This discussion introduces the important role of guanxi in Chinese/Taiwanese society and also provides some new insights of guanxi in Chinese/Taiwanese social interactions. Besides, it also illustrates the effect of guanxi on knowledge accumulation and resource development in Chinese/Taiwanese social networks. Furthermore, I stress on the effect of social networks which could contribute to different learning efficiency and innovation capability. These comprehensive discussions about their learning efficiency between two different types of social networks could not only present the influences of social capital and guanxi on their internal learning but also provide an in-depth understanding on learning in smaller family and non-family businesses in Taiwan. Thus, this thesis is constructed by the theoretical basis of social capital, guanxi and organisational learning. The contributions cover the development of each theory respectively and also the integrated findings with evidence in family and non-family businesses
Preventive and therapeutic role of traditional Chinese herbal medicine in hepatocellular carcinoma
AbstractHepatocellular carcinoma (HCC) is one of the most prevalent malignancies worldwide. The clinical management of HCC remains a substantial challenge. Although surgical resection of tumor tissues seems promising, a high recurrence and/or metastasis rate accounting for disease-related death has led to an urgent need for improved postsurgical preventive/therapeutic clinical intervention. Developing advanced target-therapy agents such as sorafenib appears to be the only effective clinical intervention for patients with HCC to date, but only limited trials have been conducted in this regard. Because of their enhanced preventive/therapeutic effects, traditional Chinese herbal medicine (CHM)-derived compounds are considered suitable agents for HCC treatment. The CHM-derived compounds also possess multilevel, multitarget, and coordinated intervention effects, making them ideal candidates for inhibition of tumor progression and HCC metastasis. This article reviews the anticancer activity of various CHMs with the hope of providing a better understanding of how to best use CHM for HCC treatment
The Protection of Hepatocyte Cells from the Effects of Oxidative Stress by Treatment with Vitamin E in Conjunction with DTT
We investigated the effect of vitamin E on membrane protein thiols under oxidative stress, which we induced by treating hepatocytes with tert-butyl hydroperoxide (TBH) for 60 mins. Those cells which we pretreated with vitamin E formed fewer blebs (22.3% compared to 60.0% in nonvitamin E-treated cells) and maintained cytosolic calcium concentration and the number of membrane protein thiols instead of showing the usual symptoms in cells undergoing oxidative stress. Dithiothreitol (DTT) also commonly reduces bleb formation in hepatocytes affected by TBH. However, our experiments clearly demonstrate that DTT does not prevent the changes in cytosolic calcium and membrane protein thiols in the blebbing cells. Consequently, we decided to pretreat cells with both DTT and vitamin E and found that the influence of TBH was entirely prevented. These findings may provide us with a new aspect for investigating the mechanism of bleb formation under oxidative stress
Association between copy number variation of complement component C4 and Graves' disease
<p>Abstract</p> <p>Background</p> <p>Gene copy number of complement component <it>C4</it>, which varies among individuals, may determine the intrinsic strength of the classical complement pathway. Presuming a major role of complement as an effecter in peptide-mediated inflammation and phagocytosis, we hypothesized that <it>C4 </it>genetic diversity may partially explain the development of Graves' disease (GD) and the variation in its outcomes.</p> <p>Methods</p> <p>A case-control study including 624 patients with GD and 160 healthy individuals were enrolled. CNV of <it>C4 </it>isotypes (<it>C4A </it>and <it>C4B</it>) genes were performed by quantitative real-time polymerase chain reaction analysis. Statistical comparison and identification of CNV of total <it>C4, C4 </it>isotypes (<it>C4A </it>and <it>C4B</it>) and <it>C4 </it>polymorphisms were estimated according to the occurrence of GD and its associated clinical features.</p> <p>Results</p> <p>Individuals with 4, 2, and 2 copies of <it>C4</it>, <it>C4A </it>and <it>C4B </it>genes, especially those with A2B2 polymorphism may associate with the development of GD (p = 0.001, OR = 10.994, 95% CI: 6.277-19.255; p = 0.008, OR = 1.732, 95% CI: 1.190-2.520; p = 2.420 × 10-5, OR = 2.621, 95% CI: 1.791-3.835; and <it>p </it>= 1.395 × 10<sup>-4</sup>, OR = 2.671, 95% CI: 1.761-4.052, respectively). Although the distribution of copy number for total <it>C4</it>, <it>C4 </it>isotypes as well as <it>C4 </it>polymorphisms did not associate with the occurrence of goiter, nodular hyperplasia, GO and myxedema, <2 copies of <it>C4A </it>may associate with high risk toward vitiligo in patients with GD (<it>p </it>= 0.001, OR = 5.579, 95% CI: 1.659-18.763).</p> <p>Conclusions</p> <p>These results may be further estimated for its clinical application on GD and the vitiligo in patients with GD.</p
- …