57 research outputs found

    The effects of integrating mobile devices with teaching and learning on students' learning performance: A meta-analysis and research synthesis

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    AbstractMobile devices such as laptops, personal digital assistants, and mobile phones have become a learning tool with great potential in both classrooms and outdoor learning. Although there have been qualitative analyses of the use of mobile devices in education, systematic quantitative analyses of the effects of mobile-integrated education are lacking. This study performed a meta-analysis and research synthesis of the effects of integrated mobile devices in teaching and learning, in which 110 experimental and quasiexperimental journal articles published during the period 1993–2013 were coded and analyzed. Overall, there was a moderate mean effect size of 0.523 for the application of mobile devices to education. The effect sizes of moderator variables were analyzed and the advantages and disadvantages of mobile learning in different levels of moderator variables were synthesized based on content analyses of individual studies. The results of this study and their implications for both research and practice are discussed

    Rho Kinases Regulate the Renewal and Neural Differentiation of Embryonic Stem Cells in a Cell Plating Density–Dependent Manner

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    [[abstract]]BACKGROUND: Rho kinases (ROCKs) mediate cell contraction, local adhesion, and cell motility, which are considered to be important in cell differentiation. We postulated that ROCKs are involved in controlling embryonic stem (ES) cell renewal and differentiation. METHODOLOGY/PRINCIPAL FINDINGS: CCE, a murine ES cell, was treated with Y-27632 for 48 to 96 hours and colony formation was evaluated. Y-27632 blocked CCE colony formation and induced CCE to grow as individual cells, regardless of the initial seeding cell density either at 10(4)/cm(2) ("high" seeding density) or 2x10(3)/cm(2) ("low" density). However, at high seeding density, Y-27632-treated cells exhibited reduction of alkaline phosphatase (AP) staining and Oct3/4 expression. They expressed SOX-1, nestin, and MAP2c, but not betaIII-tubulin or NG-2. They did not express endoderm or mesoderm lineage markers. After removal of Y-27632, the cells failed to form colonies or regain undifferentiated state. Silencing of ROCK-1 or ROCK-2 with selective small interference RNA induced CCE morphological changes similar to Y-27632. Silencing of ROCK-1 or ROCK-2 individually was sufficient to cause reduction of AP and Oct3/4, and expression of SOX-1, nestin, and MAP2c; and combined silencing of both ROCKs did not augment the effects exerted by individual ROCK siRNA. Y-27632-treated CCE cells seeded at 2x10(3) or 6.6x10(3) cells/cm(2) did not lose renewal factors or express differentiation markers. Furthermore, they were able to form AP-positive colonies after removal of Y-27632 and reseeding. Similar to ROCK inhibition by Y-27632, silencing of ROCK-1 or ROCK-2 in cells seeded at 2x10(3)/cm(2) did not change renewal factors. CONCLUSIONS/SIGNIFICANCE: We conclude that ROCKs promote ES cell colony formation, maintain them at undifferentiated state, and prevent them from neural differentiation at high seeding density. ROCK inhibition represents a new strategy for preparing large numbers of neural progenitor cells

    Quantitative analysis of nanoparticle internalization in mammalian cells by high resolution X-ray microscopy

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    <p>Abstract</p> <p>Background</p> <p>Quantitative analysis of nanoparticle uptake at the cellular level is critical to nanomedicine procedures. In particular, it is required for a realistic evaluation of their effects. Unfortunately, quantitative measurements of nanoparticle uptake still pose a formidable technical challenge. We present here a method to tackle this problem and analyze the number of metal nanoparticles present in different types of cells. The method relies on high-lateral-resolution (better than 30 nm) transmission x-ray microimages with both absorption contrast and phase contrast -- including two-dimensional (2D) projection images and three-dimensional (3D) tomographic reconstructions that directly show the nanoparticles.</p> <p>Results</p> <p>Practical tests were successfully conducted on bare and polyethylene glycol (PEG) coated gold nanoparticles obtained by x-ray irradiation. Using two different cell lines, EMT and HeLa, we obtained the number of nanoparticle clusters uptaken by each cell and the cluster size. Furthermore, the analysis revealed interesting differences between 2D and 3D cultured cells as well as between 2D and 3D data for the same 3D specimen.</p> <p>Conclusions</p> <p>We demonstrated the feasibility and effectiveness of our method, proving that it is accurate enough to measure the nanoparticle uptake differences between cells as well as the sizes of the formed nanoparticle clusters. The differences between 2D and 3D cultures and 2D and 3D images stress the importance of the 3D analysis which is made possible by our approach.</p

    Pengembangan Suplemen Pembelajaran Fisika Gelombang Elektromagnetik Cahaya Sebagai Partikel Memanfaatkan Virtual Laboratorium

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    This research has been done to make a supplement for physics learning about light electromagnetic wave as a particle using virtual laboratory. The population of this research was the second year science-students at SMA Muhammadiyah 1 Metro. This development is begun by needs analysis, then identification of resource which is the background of this developmental research. The next step is, identifying the product specification then developing products which contained a tutorial book for teacher and a work sheet for student (LKS). The material and design expert test result is that those products were approved. The external test resulted by users show that the LKS was attractive, very easy to use, and useful. It also was effective to be used as a learning resource because 80% of students reached the passing grade.Telah dilakukan penelitian untuk mengembangkan suplemen pembelajaran fisika gelombang elektromagnetik cahaya sebagai partikel dengan memanfaatkan virtual laboratorium. Populasi penelitian pengembangan ini adalah siswa kelas XI IPA di SMA Muhammadiyah 1 Metro. Pengembangan ini diawali dengan analisis kebutuhan, kemudian identifikasi sumber daya yang melatar belakangi pengembangan. Langkah selanjutnya identifikasi spesifikasi produk yang dilanjutkan dengan mengembangkan produk berupa LKS untuk siswa dan buku panduan untuk guru. Hasil uji internal oleh ahli materi dan ahli desain menyatakan produk yang dikembangkan layak digunakan sebagai media pembelajaran. Hasil uji eksternal oleh pengguna menunjukkan kualitas media pembelajaran menarik, sangat mudah digunakan, dan bermanfaat serta efektif digunakan sebagai media pembelajaran dengan presentase hasil belajar sebesar 80% siswa telah memenuhi KKM

    NĂ€raomgivningstryck hastighetskarta avbildning

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    Catalytic reactions on solid surfaces have been studied under Ultra-high vacuum (UHV) conditions for decades. These studies provide crucial information for catalytic reactions, such as surface structures, adsorption sites, and reaction mechanisms. However, industrial catalysis operates under high gas pressure to increase the reaction rate, so the knowledge we learn from the previous UHV studies may not be able to directly transfer to the industry. This difference is referred to as the “pressure gap”, and it represents the difficulties that scientists encounter when attempting to investigate and comprehend catalytic reactions at high pressure. To address this issue, in situ/operando techniques and instruments have been developed to study reactions at pressures closer to real-world applications.The present thesis aims to showcase the new instrument, Near-Ambient Pressure Velocity Map Imaging (NAP-VMI), and its applications to molecular spectroscopy and surface science at near-ambient pressures. This instrument features a velocity map imaging (VMI) setup with redesigned ion optics and uses differential pumping to achieve a working pressure of 10−3 mabr. It allows time-resolved measurements at microsecond time scales using the pump-probe technique with a pulsed molecular beam and a pulsed laser. The performance is validated using N2O photodissociation and N2 surface scattering. CO oxidation on Pd(110) and Pd(100) surfaces is studied at elevated oxygen pressure (1×10−5 mbar) where the surfaces reconstruct.The results show the suppression of CO2 production in oxygen rich environments for both surfaces. The difference in kinetics and dynamics behavior between the two surfaces also suggests that surface structures and adsorption sites are important in the reaction mechanisms. These findings highlight the importance of surface structure in catalytic reactions and pave the way for more effective catalysts to be designed by tailoring surface properties and reaction conditions.Katalytiska reaktioner pĂ„ fasta ytor har studerats under ultrahögt vakuum (UHV) i Ă„rtionden. Dessa studier ger avgörande information för katalytiska reaktioner, sĂ„som ytstrukturer, adsorptionsstĂ€llen och reaktionsmekanismer. Industriell katalys arbetar dock under högt gastryck för att öka reaktionshastigheten, sĂ„ kunskapen vi lĂ€r oss frĂ„n de tidigare UHV-studierna kanske inte direkt kan överföras till industrin. Denna skillnad kallas “tryckgapet” och den representerar de svĂ„righeter som forskare möter nĂ€r de försöker undersöka och förstĂ„ katalytiska reaktioner vid högt tryck. För att lösa detta problem har in situ/operando metoder och instrument utvecklats för att studera reaktioner vid tryck som ligger nĂ€rmare verkliga tillĂ€mpningar. Den föreliggande avhandlingen syftar till att visa upp det nya instrumentet, nĂ€ra-omgivande tryckhastighetskarta-avbildning (NAP-VMI) och dess tillĂ€mpningar för molekylĂ€r spektroskopi och ytvetenskap vid nĂ€ra-omgivande tryck. Detta instrument har en hastighetskarta-avbildning (VMI) med omdesignadjonoptik och anvĂ€nder differentialpumpning för att uppnĂ„ ett arbetstryckpĂ„ 10−3 mabr. Den tillĂ„ter tidsupplösta mĂ€tningar pĂ„ mikrosekunders tidsskalormed hjĂ€lp av pump-probe-teknik med pulsmolekylĂ€r strĂ„le och pulslaser. Prestandan valideras med hjĂ€lp av N2O fotodissociation och N2 ytspridning. CO oxidation pĂ„ Pd(110) och Pd(100) ytan studeras vid förhöjt syretryck (1 × 10−5 mbar) dĂ€r ytorna rekonstrueras. Resultaten visar undertryckandet av CO2 produktion i syrerika miljöer för bĂ„da ytorna. Skillnaden i kinetik och dynamikbeteende mellan de tvĂ„ ytorna tyder ocksĂ„ pĂ„ att ytstrukturer och adsorptionsstĂ€llen Ă€r viktiga i reaktionsmekanismerna. Dessa fynd framhĂ€ver vikten av ytstruktur i katalytiska reaktioner och banar vĂ€g för mer effektiva katalysatorer som kan utformas genom att skrĂ€ddarsy ytegenskaper och reaktionsförhĂ„llanden.QC 20240117</p

    Measurement equivalence between the original and estimated Mini-Mental State Examination in people with dementia

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    [[abstract]]Background: The Cognitive Abilities Screening Instrument (CASI) is increasingly used to assess general cognitive function in people with dementia. The Mini-Mental State Examination (MMSE) score can be converted from the CASI (i.e., the estimated MMSE). Recognizing that measurement equivalence is critical to meaningfully representing one with the other, we aimed to determine whether the estimated MMSE score obtained from the CASI was equivalent to the original MMSE in people with dementia. Methods: We obtained 110 data points for the MMSE and CASI scores in people with dementia. The intraclass correlation coefficient (ICC), Pearson's r, percent of standard error of measurement (SEM%), paired t-test, and effect size (Cohen's d) were used to investigate the equivalence. Results: To examine the equivalence between the original and estimated MMSE score, the ICC and Pearson's r of the total score and six domains were 0.62-0.95 and 0.62-0.96, respectively. The SEM% of the total score and six domains were 0.6-8.9%. The paired t-test results showed a significant difference (p < 0.05) between the total score and the three domains. The Cohen's d of the total score and six domains were 0.06-0.27. Conclusions: The estimated MMSE score was found to have moderate to excellent equivalence to the original MMSE score. The three domains (i.e., registration, attention and calculation, and visual-constructional ability) with moderate equivalence should be used cautiously to interchange with the original MMSE in people with dementia

    Dextromethorphan Reduces Oxidative Stress and Inhibits Uremic Artery Calcification

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    Medial vascular calcification has emerged as a key factor contributing to cardiovascular mortality in patients with chronic kidney disease (CKD). Vascular smooth muscle cells (VSMCs) with osteogenic transdifferentiation play a role in vascular calcification. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitors reduce reactive oxygen species (ROS) production and calcified-medium–induced calcification of VSMCs. This study investigates the effects of dextromethorphan (DXM), an NADPH oxidase inhibitor, on vascular calcification. We used in vitro and in vivo studies to evaluate the effect of DXM on artery changes in the presence of hyperphosphatemia. The anti-vascular calcification effect of DXM was tested in adenine-fed Wistar rats. High-phosphate medium induced ROS production and calcification of VSMCs. DXM significantly attenuated the increase in ROS production, the decrease in ATP, and mitochondria membrane potential during the calcified-medium–induced VSMC calcification process (p &lt; 0.05). The protective effect of DXM in calcified-medium–induced VSMC calcification was not further increased by NADPH oxidase inhibitors, indicating that NADPH oxidase mediates the effect of DXM. Furthermore, DXM decreased aortic calcification in Wistar rats with CKD. Our results suggest that treatment with DXM can attenuate vascular oxidative stress and ameliorate vascular calcification

    The Association between Quality of Life and Nursing Home Facility for the Elderly Population: A Systematic Review and Meta-Analysis

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    [[abstract]]Background: To investigate the association between quality of life and nursing home facility for the elderly population. Methods: We searched the PubMed, Medline, and Cochrane Library for relevant perspective studies without language limitations from inception to 17th June 2020 for relevant publications with a priori defined inclusion and exclusion criteria. Two authors independently selected studies, assessed risk of bias, and extracted data. The disagreement was resolved by discussion with a third author. Results: There are 18 articles involved in the final meta-analysis. The disparities were found of accessing the quality of life (World Health Organization Quality-of-Life, Quality of Life in Last-Stage Dementia, Nottingham Health Profile-Turkish Version, EUROPE Health Interview Survey-QoL , Visual analogue Scales, Flanagan Quality of Life Scale) and the level of independence (Barthel Index, Kahoku Aging Longitudinal Study Scale, Visual Analogue Scales, Activities of Daily Living Scales, Instrumental Activities of Daily Living Scales). Conclusion: The available limited, very low-quality evidence does not support a significant association between quality of life and nursing home facility for the elderly population. Further rigorous and longterm follow-up studies should be conducted with more objective measures

    Association between quality of life and nursing home facility for the elderly population: a systematic review and meta-analysis

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    [[abstract]]Background: To investigate the association between quality of life and nursing home facility for the elderly population. Methods: We searched the PubMed, Medline, and Cochrane Library for relevant perspective studies without language limitations from inception to 17th June 2020 for relevant publications with a priori defined inclusion and exclusion criteria. Two authors independently selected studies, assessed risk of bias, and extracted data. The disagreement was resolved by discussion with a third author. Results: There are 18 articles involved in the final meta-analysis. The disparities were found of accessing the quality of life (World Health Organization Quality-of-Life, Quality of Life in Last-Stage Dementia, Nottingham Health Profile-Turkish Version, EUROPE Health Interview Survey-QoL , Visual analogue Scales, Flanagan Quality of Life Scale) and the level of independence (Barthel Index, Kahoku Aging Longitudinal Study Scale, Visual Analogue Scales, Activities of Daily Living Scales, Instrumental Activities of Daily Living Scales). Conclusion: The available limited, very low-quality evidence does not support a significant association between quality of life and nursing home facility for the elderly population. Further rigorous and longterm follow-up studies should be conducted with more objective measures

    The Association between Quality of Life and Nursing Home Facility for the Elderly Population: A Systematic Review and Meta-Analysis

    No full text
    [[abstract]]Background: To investigate the association between quality of life and nursing home facility for the elderly population. Methods: We searched the PubMed, Medline, and Cochrane Library for relevant perspective studies without language limitations from inception to 17th June 2020 for relevant publications with a priori defined inclusion and exclusion criteria. Two authors independently selected studies, assessed risk of bias, and extracted data. The disagreement was resolved by discussion with a third author. Results: There are 18 articles involved in the final meta-analysis. The disparities were found of accessing the quality of life (World Health Organization Quality-of-Life, Quality of Life in Last-Stage Dementia, Nottingham Health Profile-Turkish Version, EUROPE Health Interview Survey-QoL , Visual analogue Scales, Flanagan Quality of Life Scale) and the level of independence (Barthel Index, Kahoku Aging Longitudinal Study Scale, Visual Analogue Scales, Activities of Daily Living Scales, Instrumental Activities of Daily Living Scales). Conclusion: The available limited, very low-quality evidence does not support a significant association between quality of life and nursing home facility for the elderly population. Further rigorous and longterm follow-up studies should be conducted with more objective measures
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