43 research outputs found
Modified Sagnac experiment for measuring travel-time difference between counter-propagating light beams in a uniformly moving fiber
A fiber optic conveyor has been developed for investigating the travel-time difference between two counter-propagating light beams in uniformly moving fiber. Our finding is that there is a travel-time difference Δt = 2vΔl/c2 in a fiber segment of length Δl moving with the source and detector at a speed v, whether the segment is moving uniformly or circularly
Modified Sagnac experiment for measuring travel-time difference between counter-propagating light beams in a uniformly moving fiber
A fiber optic conveyor has been developed for investigating the travel-time
difference between two counter-propagating light beams in uniformly moving
fiber. Our finding is that there is a travel-time difference
Deltat=2vDeltal/c^2 in a fiber segment of length Deltal moving with the source
and detector at a speed v, whether the segment is moving uniformly or
circularly.Comment: 4 pages, including 4 figure
Generalized Sagnac Effect
Experiments were conducted to study light propagation in a light waveguide
loop consisting of linearly and circularly moving segments. We found that any
segment of the loop contributes to the total phase difference between two
counterpropagating light beams in the loop. The contribution is proportional to
a product of the moving velocity v and the projection of the segment length
Deltal on the moving direction, Deltaphi=4pivDeltal/clambda. It is independent
of the type of motion and the refractive index of waveguides. The finding
includes the Sagnac effect of rotation as a special case and suggests a new
fiber optic sensor for measuring linear motion with nanoscale sensitivity.Comment: 3 pages (including 3 figures
Polymorphisms of ERCC1, XPD, XRCC1 and XPG Predict Clinical Outcome in Advanced Gastric Cancer Patients Receiving Oxaliplatin-Based Chemotherapy in Chinese Population
OBJECTIVE To investigate whether polymorphisms in ERC1, XPD, XPG, XRCC1 genes are associated with clinical outcomes in advanced gastric cancer (AGC) patients treated with oxaliplatin-based chemotherapy. METHODS The genetic polymorphisms in ERCC1, XPD, XPG, XRCC1 were determined in 94 advanced gastric cancer patients treated with oxaliplatin-based chemotherapy, using TaqMan-MGB probes. The clinical response of 60 patients with stage IV disease, time to progression (TTP) and overall survival (OS) of 94 patients were evaluated.RESULTS The overall disease control rate (CR + PR + SD) of the 60 patients in stage IV was 70% (42/60). Patients with XRCC1 399 G/G, XPG 46 C/C genotypes showed enhanced response to the oxaliplatin-based chemotherapy compared to those with other genotypes (P 0.05). CONCLUSION Testing for XRCC1 399, XPG 46 polymorphisms may allow identification of the gastric cancer patients who will benefit from oxaliplatin-based chemotherapy. Specific polymorphisms may influence clinical outcomes of AGC patients. Selecting specific chemotherapy based on pretreatment genotyping represents an innovative strategy that warrants prospective studies
Modified Sagnac experiment for measuring travel-time difference between counter-propagating light beams in a uniformly moving fiber
A fiber optic conveyor has been developed for investigating the travel-time difference between two counter-propagating light beams in uniformly moving fiber. Our finding is that there is a travel-time difference Δt=2vΔl/c2 in a fiber segment of length Δl moving with the source and detector at a speed v, whether the segment is moving uniformly or circularly
7, 8-Dihydroxyflavone Protects an Endothelial Cell Line from H2O2 Damage.
7, 8-dihydroxyflavone (7, 8-DHF), a selective agonist for TrkB receptors, has been well studied for its neurotrophic functions. However, its roles outside the neural tissues have scarcely been studied as yet. In this study, we investigated the protecting roles of 7, 8-DHF in EA.hy926 cells, a human umbilic vein endothelial cell line which was exposed to hydrogen peroxide (H2O2). We found that 7, 8-DHF significantly protected the cells from being damaged by H2O2 through suppression of apoptosis, attenuation of inflammatory factor releasing and inhibition of reactive oxygen species generation. The potent biological effects of 7, 8-DHF were probably executed via its binding to TrkB receptors because the receptor specific antagonist ANA-12 significantly blocked its protecting effects. The protecting roles of 7, 8-DHF in EA.hy926 cells suggest that it will be a promising compound to be developed into a health product that definitely benefits endothelial functions and prevents cardiovascular diseases