1,352 research outputs found
The Design and Fabrication of Platform Device for Dna Amplification
Thermalcycler were extensively used machine for amplify DNA sample. One of
the major problems in the working time was that it spent most of time for
cooling and heating. In order to improve the efficient, this study presented a
novel method for amplify DNA sample. For this concept, the DNA sample in the
silicon chamber which was pushed by a beam through three temperature regions
around a center and then the DNA segments could be amplified rapidly after 30
cycles. The polymerase chain reaction platform was composed of thin-film
heaters, copper plates, DC powers, and temperature controllers. The
photolithography and bulk etching technologies were utilized to construct the
thin-film heater and DNA reaction chambers. Finally, 1 pound gL 100bp DNA
segment of E. coli K12 was amplified successfully within 36 minutes on this PCR
platform.Comment: Submitted on behalf of TIMA Editions
(http://irevues.inist.fr/tima-editions
Fabrication of Switches on Polymer-Based by Hot Embossing
In MEMS technology, most of the devices are fabricated on glass or silicon
substrate. However, this research presents a novel manufacture method that is
derived from conventional hot embossing technology to fabricate the
electrostatic switches on polymer material. The procedures of fabrication
involve the metal deposition, photolithography, electroplating, hot embossing
and hot embed techniques. The fundamental concept of the hot embed technology
is that the temperature should be increased above Tg of polymer, and the
polymer becomes plastic and viscous and could be molded. According to the
fundamental concept, the metal layer on the silicon/glass substrate could be
embedded into polymer material during the hot embossing process. Afterward, the
metal layer is bonded together with the polymer after removing the substrate in
the de-embossing step. Finally, the electrostatic switch is fabricated on
polymethylmethacrylate(PMMA) material to demonstrate the novel method.Comment: Submitted on behalf of TIMA Editions
(http://irevues.inist.fr/tima-editions
Ischemic conditioning by short periods of reperfusion attenuates renal ischemia/reperfusion induced apoptosis and autophagy in the rat
Prolonged ischemia amplified iscehemia/reperfusion (IR) induced renal apoptosis and autophagy. We hypothesize that ischemic conditioning (IC) by a briefly intermittent reperfusion during a prolonged ischemic phase may ameliorate IR induced renal dysfunction. We evaluated the antioxidant/oxidant mechanism, autophagy and apoptosis in the uninephrectomized Wistar rats subjected to sham control, 4 stages of 15-min IC (I15 × 4), 2 stages of 30-min IC (I30 × 2), and total 60-min ischema (I60) in the kidney followed by 4 or 24 hours of reperfusion. By use of ATP assay, monitoring O2-. amounts, autophagy and apoptosis analysis of rat kidneys, I60 followed by 4 hours of reperfusion decreased renal ATP and enhanced reactive oxygen species (ROS) level and proapoptotic and autophagic mechanisms, including enhanced Bax/Bcl-2 ratio, cytochrome C release, active caspase 3, poly-(ADP-ribose)-polymerase (PARP) degradation fragments, microtubule-associated protein light chain 3 (LC3) and Beclin-1 expression and subsequently tubular apoptosis and autophagy associated with elevated blood urea nitrogen and creatinine level. I30 × 2, not I15 × 4 decreased ROS production and cytochrome C release, increased Manganese superoxide dismutase (MnSOD), Copper-Zn superoxide dismutase (CuZnSOD) and catalase expression and provided a more efficient protection than I60 against IR induced tubular apoptosis and autophagy and blood urea nitrogen and creatinine level. We conclude that 60-min renal ischemia enhanced renal tubular oxidative stress, proapoptosis and autophagy in the rat kidneys. Two stages of 30-min ischemia with 3-min reperfusion significantly preserved renal ATP content, increased antioxidant defense mechanisms and decreased ischemia/reperfusion enhanced renal tubular oxidative stress, cytosolic cytochrome C release, proapoptosis and autophagy in rat kidneys
Did the S.A.R.S. epidemic weaken the integration of Asian stock markets? Evidence from smooth time-varying cointegration analysis
The purpose of this study is to examine the effect of the Severe
Acute Respiratory Syndrome (S.A.R.S.) epidemic on the long-run
relationship between China and four Asian stock markets. To this
end, we first employ the advanced smooth time-varying cointegration
model to investigate the existence of a time-varying cointegration
relation among these markets and then employ the difference-indifferences
approach to analyse whether or not the S.A.R.S. epidemic
impacted the long-run relation between China and these four markets
during the period 1998–2008, covering 5 years before and after the
S.A.R.S. outbreak. Our results support the existence of a time-varying
cointegration relation in the aggregate stock price indices, and that
the S.A.R.S. epidemic did weaken the long-run relationship between
China and the four markets. Therefore, stockholders and policy makers
should be concerned about the influence of catastrophic epidemic
diseases on the financial integration of stock market in Asia
Changes in corneal curvature after wearing the orthokeratology lens
AbstractIntroductionThe orthokeratology lens (OK lens) is designed to reshape the cornea and correct refraction error. Owing to the convenience of ceasing the use of glasses during the day, the use of the OK lens is increasing in myopic children. In this study, changes in corneal curvature and astigmatism after wearing the OK lens were analyzed.MethodsThis retrospective cohort study included 65 children (130 eyes) who underwent full and regular examinations. None of the participants had any ocular disease other than myopia and astigmatism. The OK lenses used in this study were four-zone, reverse-geometry lenses. The corneal curvature of each patient was checked annually after the patients discontinued daily wearing of the OK lens for 10 days. Student t test and repeated measures analysis of variance (ANOVA) analyses were performed to compare the results.ResultsThe radius of corneal curvature showed a progressive annual increase with significant differences, both in the steepest and flattest radius of the corneal curvature (p < 0.001 and p = 0.001, respectively). The mean radius of the steepest and flattest corneal curvature increased significantly from baseline to the following years consecutively (all p < 0.001). Nevertheless, astigmatism did not change significantly in any of the tests.ConclusionCorneal curvature changed as the patients grew older. There was a statistically significant increase in the radius of the corneal curvature in the myopic children studied. For correct fit of OK lenses, the radius of the corneal curvature should be regularly checked prior to dispensing a new set of lenses
(Z)-4-(2-Hydroxybenzylidene)-1-methyl-2-phenyl-1H-imidazol-5(4H)-one
In the title compound, C17H14N2O2, the asymmetric unit comprises two molecules that are comformationally similar [the dihedral angles between the phenyl rings in each are 46.35 (2) and 48.04 (3)°], with the conformation stabilized by intramolecular O—H⋯N hydrogen bonds, which generate S(7) rings. In the crystal, inversion-related molecules are linked by pairs of weak C—H⋯O hydrogen bonds, forming dimers with an R
2
2(16) graph-set motif. Weak inter-ring π–π stacking is observed in the structure, the shortest centroid-to-centroid distance being 3.7480 (13) Å
(E)-4-[(4-Diethylamino-2-hydroxybenzylidene)amino]benzonitrile
The title compound, C18H19N3O, displays an E conformation with respect to the C=N double bond. The dihedral angle between the mean planes of the two benzene rings is 24.49 (3)°. An intramolecular O—H⋯N hydrogen bond generates an S(6) ring. In the crystal, molecules are linked by nonclassical intermolecular C—H⋯O hydrogen bonds to form an infinite one-dimensional chain along [010], generating a C(8) motif
Theorizing the Role of Sport in State-Politics
If ever there was a perfect marriage, one would be hard pressed to find a more compatible couple than sport and politics. State intervention in sport has been evidenced in many countries throughout history. Today, sport and politics are still inextricabl
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