3,897 research outputs found
On the amperometric detection and electrocatalytic analysis of ascorbic acid and dopamine using a poly(acriflavine)-modified electrode
No full textFabricating an Amperometric Cholesterol Biosensor by a Covalent Linkage between Poly(3-thiopheneacetic acid) and Cholesterol Oxidase
No full textIn this study, use of the covalent enzyme immobilization method was proposed to attach cholesterol oxidase (ChO) on a conducting polymer, poly(3-thiopheneacetic acid), [poly(3-TPAA)]. Three red-orange poly(3-TPAA) films, named electrodes A, B and C, were electropolymerized on a platinum electrode by applying a constant current of 1.5 mA, for 5, 20 and 100 s, respectively. Further, 1-ethyl-3-(3-dimethylamiopropyl)carbodiimide hydrochloride (EDC‧HCl) and N-hydroxysuccinimide (NHS) were used to activate the free carboxylic groups of the conducting polymer. Afterwards, the amino groups of the cholesterol oxidase were linked on the activated groups to form peptide bonds. The best sensitivity obtained for electrode B is 4.49 mA M-1 cm-2,with a linear concentration ranging from 0 to 8 mM, which is suitable for the analysis of cholesterol in humans. The response time (t95) is between 70 and 90 s and the limit of detection is 0.42 mM, based on the signal to noise ratio equal to 3. The interference of species such as ascorbic acid and uric acid increased to 5.2 and 10.3% of the original current response, respectively, based on the current response of cholesterol (100%). With respect to the long-term stability, the sensing response retains 88% of the original current after 13 days
Enhancing dopamine detection using a glassy carbon electrode modified with MWCNTs, quercetin, and Nafion (R)
No full textFabrication of a molecularly imprinted polymer sensor by self-assembling monolayer/mediator system
No full textA PC parallel port button box provides millisecond response time accuracy under Linux
Full text linkFor psychologists, it is sometimes necessary to measure people's reaction times to the nearest millisecond. This article describes how to use the PC parallel port to receive signals from a button box to achieve millisecond response time accuracy. The workings of the parallel port, the corresponding port addresses, and a simple Linux program for controlling the port are described. A test of the speed and reliability of button box signal detection is reported. If the reader is moderately familiar with Linux, this article should provide sufficient instruction for him or her to build and test his or her own parallel port button box. This article also describes how the parallel port could be used to control an external apparatus
Functions of CXC Ligand Family in Pancreatic Tumour Microenvironment
No full text© 2021 Nien-Hung LeeChemoresistance is the major contributor to the low survival of pancreatic cancer
(PC). PC progression is a complex process reliant on interactions between tumour and
tumour microenvironment (TME). A family of structurally similar inflammatory
chemokines, namely CXC ligands (CXCLs), were recently discovered to play
important roles in various cancer types, including PC. This thesis aimed to investigate
the role of CXCL5 in chemoresistance of PC.
In both human and mice PC cell lines tested, CXCL5 expression was dramatically
upregulated. The expressions of CXCL5, CXCL10 and selected CSC genes were
various in gemcitabine resistant cell lines, and gemcitabine treated cells. However, in
mouse xenografted tumour samples, which was generated from a patient-derived cell
line, gemcitabine alone or in combination with other chemotherapeutic reagents led to
increased CXCL5 protein level while CXCL10 level remained unchanged. These
results suggested that expression of CXCL5 may be stimulated upon administration of
gemcitabine or other chemotherapeutic reagents. Therefore, CXCL5 has a role in
chemoresistance and clinical importance in PC; however, the mechanisms involved
deserves a careful investigation.
To determine whether CXCL5 mediates chemoresistance in PC, CXCL5 expression
in MiaPaCa-2 cells was knocked down by shRNA. To determine whether CXCL5
mediated chemoresistance in vitro, two chemotherapeutic drugs, were used to treat a
negative control (NC) and CXCL5 knockdown (KD) clones. In the cell proliferation
assays, CXCL5 was found to mediate the resistance to gemcitabine and 5-fluouracil (5-
FU). Mice carrying xenografted tumours inoculated by either NC or CXCL5 KD cells
II
were treated with gemcitabine. CXCL5 KD suppressed tumour growth and enhanced
the inhibitory effect of gemcitabine by decreasing proliferation and promoting
apoptosis These results indicated that knockdown of CXCL5 sensitized PC cell
response to gemcitabine and 5-FU, suggesting that CXCL5 mediates chemoresistance
in PC.
Finally, the global proteomic analysis showed CXCL5 knockdown resulted in
significant changes in expression of several proteins. Each of these proteins had a
distinct biological function in cancer as determined with KEGG pathway analysis and
NCBI. From the phosphor-proteomic analysis, CXCL5 knockdown induced significant
changes of certain phosphorylated proteins. Cross-referencing with the database of
NCBI clearly identified the biological functions of these proteins. Although
experimental and clinical validation are necessary, CXCL5 serves as a pivotal
molecular target in overcoming chemoresistance and eliminating PC tumours in clinical
practices.
In summary, these studies have revealed that CXCL5 plays an important role in
chemoresistance and activates several intracellular pathways that contribute to
resistance to therapeutic treatments and PC progression. Therefore, CXCL5 could serve as a potential molecular target in reversing chemoresistance in pancreatic cancer
Millisecond accuracy video display using OpenGL under Linux
Full text linkTo measure people’s reaction times to the nearest millisecond, it is necessary to know exactly when
a stimulus is displayed. This article describes how to display stimuli with millisecond accuracy on a
normal CRT monitor, using a PC running Linux. A simple C program is presented to illustrate how this
may be done within X Windows using the OpenGL rendering system. A test of this system is reported
that demonstrates that stimuli may be consistently displayed with millisecond accuracy. An algorithm
is presented that allows the exact time of stimulus presentation to be deduced, even if there are relatively
large errors in measuring the display time
Frontmatter (Titlepage, Table of Contents, Author List, PC List, Reviewer List)
No full textFront matter including table of contents, author list, PC list, and reviewer list
High efficiency implementation of PC and PC stable algorithms yields three-dimensional graphs of information flow for the Earth' atmosphere
Full text linkSeptember 3, 2014.Causal discovery algorithms have recently been applied to several climate applications. In particular, in prior work we have developed methods to recover pathways of interaction in the global climate system, using the classic PC algorithm. However, standard implementations of the PC algorithm cannot handle the large number of variables and temporal models required for this application. This technical report shows that a more efficient implementation of the PC algorithm can provide speed gains of a factor of 1,000 or more. This in turn enables us to calculate graphs of information flow with much higher resolution grids. Furthermore, we can now - for the first time ever - calculate information flow graphs that extend over three dimensions, i.e. rather than just including one layer of the planet's atmosphere we can now capture interactions across several height layers
State variable simulation package for IBM-PC
No full textThis thesis was scanned from the print manuscript for digital preservation and is copyright the author.
Researchers can access this thesis by asking their local university, institution or public library to
make a request on their behalf. Monash staff and postgraduate students can use the link in the References field
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