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51.
Poh Wah Hillock R. Nazim Khan 《International Journal of Mathematical Education in Science & Technology》2019,50(7):1073-1086
ABSTRACTThis article is a follow-up to an earlier paper on the mathematics support learning tutorial programme (SLT), an intervention programme at The University of Queensland that targets students considered to be at risk of failing Calculus and Linear Algebra I, the first tertiary level mathematics subject at The University of Queensland. The first paper (Hillock, P., Jennings, M., Roberts, A., & Scharaschkin, V. (2013). Amathematics support programme for first-year engineering students. International Journal of Mathematical Education in Science and Technology, 44(7), 1030–1044) reported on the inaugural programme implemented in 2012. This article provides an update of the progress of the SLT since 2012. We provide statistics for the subsequent 12 semesters to Semester 2, 2018 and describe the evolution of the SLT since its implementation. Statistical analysis of the additional data and student feedback indicate that the SLT continues to have a positive impact on student learning, with weak students making significant gains from attending the programme. 相似文献
52.
Rapid determination of corticosterone in mouse plasma by ultra fast liquid chromatography‐tandem mass spectrometry 下载免费PDF全文
Major depressive disorder is a severe, life‐threatening and highly prevalent psychiatric disorder. A high percentage of people suffering from depression are characterized by hyperactivity of the hypothalamic–pituitary–adrenal axis, resulting in plasma glucocorticoid (cortisol in human and corticosterone in rodent) elevations. Glucocorticoid is a critical molecule in the onset of pathology of depression. A simple, highly sensitive and specific method based on ultra‐fast liquid chromatography–tandem mass spectrometry method has been developed for the quantitation of corticosterone in mouse plasma for the first time, which provides technical support for the high‐throughput measurement for clinical determination of corticosterone in biological samples. Samples were spiked with methanol to precipitate the protein, and then chromatographed on an Agilent Zorbax Eclipse Plus C18 (100 × 2.1 mm,1.8 µm) column by linear gradient elution with methanol and 0.1% formic acid as the mobile phase within 5 min. The detection of corticosterone was performed on ultra‐fast liquid chromatography–triple quadrupole tandem mass spectrometry in the positive ion. The ions [M + H]+ m/z 347.2 → m/z 311.1 for corticosterone and [M + H]+ m/z 363.2 → m/z 327.2 for hydrocortisone (internal standard) were used for quantitative determination. The lower quantification limit for corticosterone was 1 ng/mL. The validated method was successfully applied to the quantitation of corticosterone in mouse plasma. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
53.
Wei Church Poh Dr. Ho-Leung Au-Yeung Dr. Alan Kwun-Wa Chan Dr. Eugene Yau-Hin Hong Dr. Yat-Hin Cheng Dr. Ming-Yi Leung Dr. Shiu-Lun Lai Dr. Kam-Hung Low Prof. Dr. Vivian Wing-Wah Yam 《化学:亚洲杂志》2021,16(22):3669-3676
A series of heteroleptic cyclometalated platinum(II) complexes, [Pt(C^N)(O^O)], ( 1 – 10 ) with various donors and acceptors has been synthesized and characterized by 1H NMR spectroscopy, elemental analyses, infrared spectroscopy and mass spectrometry. The X-ray structure of 2 has also been determined. The electrochemical and photophysical properties of the platinum(II) complexes were studied. These experimental results have been supported by computational studies. Furthermore, two of the complexes have been employed as the active material in the fabrication of resistive memory devices, exhibiting stable binary memory performance with low operating voltage, high ON/OFF ratio and long retention time. 相似文献
54.
Charles A Gullo William YK Hwang Chye K Poh Melvin Au Geraline Cow Gerrard Teoh 《Journal of immune based therapies and vaccines》2008,6(1):1-10
Background
As the eradication of tumor cells in vivo is most efficiently performed by cytolytic T lymphocytes (CTL), various methods for priming tumor-reactive lymphocytes have been developed. In this study, a method of priming CTLs with ultraviolet (UV)-irradiated tumor cells, which results in termination of tumor cell proliferation, apoptosis, as well as upregulation of heat shock proteins (HSP) expression is described.Methods
Peripheral blood mononuclear cells (PBMC) were primed weekly with UV-irradiated or mitomycin-treated RPMI 8226 multiple myeloma cells. Following three rounds of stimulation over 21 days, the lymphocytes from the mixed culture conditions were analyzed for anti-MM cell reactivity.Results
By day 10 of cultures, PBMCs primed using UV-irradiated tumor cells demonstrated a higher percentage of activated CD8+/CD4- T lymphocytes than non-primed PBMCs or PBMCs primed using mitomycin-treated MM cells. Cytotoxicity assays revealed that primed PBMCs were markedly more effective (p < 0.01) than non-primed PBMCs in killing RPMI 8226 MM cells. Surface expression of glucose regulated protein 94 (Grp94/Gp96) and Grp78 were both found to be induced in UV-treated MM cells.Conclusion
Since, HSP-associated peptides are known to mediate tumor rejection; these data suggest that immune-mediated eradication of MM cells could be elicited via a UV-induced HSP process. The finding that the addition of 17-allylamide-17-demethoxygeldanamycin (17AAG, an inhibitor of HSP 90-peptide interactions) resulted in decreased CTL-induced cytotoxicity supported this hypothesis. Our study, therefore, provides the framework for the development of anti-tumor CTL cellular vaccines for treating MM using UV-irradiated tumor cells as immunogens. 相似文献55.
We prove inequalities relating the inradius of a convex body with interior containing no point of the integral lattice, with the volume or surface area of the body. These inequalities are tight and generalize previous results.The work of the second author was supported by the Gerhard-Hess-Forschungs-Förderpreis of the German Science Foundation (DFG) awarded to Günter M. Ziegler (Zi 475/1-1) 相似文献
56.
Hian Poh Yap 《Journal of Graph Theory》1980,4(3):309-314
Gol'dberg has recently constructed an infinite family of 3-critical graphs of even order. We now prove that if there exists a p(≥4)-critical graph K of odd order such that K has a vertex u of valency 2 and another vertex v ≠ u of valency ≤(p + 2)/2, then there exists a p-critical graph of even order. 相似文献
57.
58.
We propose that self-assembly of complicated nanocrystals can be realized by making patterns on the surface of the Stranski-Krastanow systems with the film thickness in a special range that gradual surface undulation is prohibited but island nucleation can be effected. The method has the potential to control the locations, the size, and the shapes of the self-assembled nanocrystals. 相似文献
59.
A newly developed conductivity detector, the floating resistivity detector (FRD), for microchip electrophoresis was introduced in this work. The detector design permits decoupling of the detection circuit from the high separation voltage without compromising separation efficiency. This greatly simplifies the integration of microchip electrophoresis systems. Its method of detection relies on platinum electrodes being dipped in two buffer-filled branched detection probe reservoirs on the microchip device. In this way, analytes passing through the detection window will not pass through and subsequently adsorb onto the electrodes, alleviating problems of electrode fouling due to analyte contamination and surface reactions. A customized microchip design was proposed and optimized stepwise for the new FRD system. Each branched detection probe was determined to be 4.50 mm long with a 0.075 mm detection window gap between them. The distance between the detection window and buffer waste reservoir was determined to be 1.50 mm. The optimized microchip design was subsequently used in the analysis of four groups of analytes - inorganic cations, amino acids, aminoglycosides antibiotics, and biomarkers. Based on the preliminary results obtained, the detection limits were in the range of 0.4-0.7 mg/L for the inorganic cations and 1.5-15 mg/L for the amino compounds. 相似文献
60.
The paper presents a 3-D filter chip employing both mechanical and dielectrophoretic (DEP) filtration, and its corresponding microfabrication techniques. The device structure is similar to a classical capacitor: two planar electrodes, made from a stainless steel mesh, and bonded on both sides of a glass frame filled with round silica beads. The solution with the suspension of particles flows through both the mesh-electrodes and silica beads filter. The top stainless steel mesh (with openings of 60 mum and wires of 30 mum-thickness) provides the first stage of filtration based on mechanical trapping. A second level of filtration is based on DEP by using the nonuniformities of the electric field generated in the capacitor due to the nonuniformities of the dielectric medium. The filter can work also with DC and AC electric fields. The device was tested with yeast cells (Saccharomyces cerevisae) and achieved a maximal trapping efficiency of 75% at an applied AC voltage of 200 V and a flow rate of 0.1 mL/min, from an initial concentration of cells of 5 x 10(5) cells/mL. When the applied frequency was varieted in the range between 20 and 200 kHz, a minimal value of capture efficiency (3%) was notticed at 50 kHz, when yeast cells exhibit negative DEP and the cells are repelled in the space between the beads. 相似文献