Intensity-modulated fiber Bragg grating sensor system based on radio-frequency signal measurement

Author name used in this publication: Li-Yang ShaoAuthor name used in this publication: H. Y. TamAuthor name used in this publication: C. Lu2007-2008 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

High-frequency ultrasonic hydrophone based on a cladding-etched DBR fiber laser

2007-2008 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Pressure sensor realized with polarization-maintaining photonic crystal fiber-based Sagnac interferometer

Author name used in this publication: H. Y. TamAuthor name used in this publication: Li-Yang ShaoAuthor name used in this publication: P. K. A. WaiAuthor name used in this publication: C. Lu2007-2008 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Tilted fiber grating accelerometer incorporating an abrupt biconical taper for cladding to core recoupling

2009-2010 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Bulk regeneration of optical fiber Bragg gratings

Author name used in this publication: Li-Yang Shao2012-2013 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Low Sensitivity of T-Cell Based Detection of Tuberculosis among HIV Co-Infected Tanzanian In-Patients

Objective: To evaluate the performance of QuantiFERON-TB GOLD (QFTG) in a resource-poor setting among patients with and without HIV infection.Design: Cross-sectional study.Setting: Two hospitals in Northern Tanzania.Subjects: Eighty three adult male and female inpatients.Intervention: All patients were screened for HIV infection and underwent tuberculin skin test (TST) and QFTG.Results: Eighty-three subjects were enrolled, and 29 (35%) of 83 were HIV-infected. QFTG yielded indeterminate results in 12 (22%; 95%CI 12%-34%) of 54 HIV-uninfected and 13 (45%; 95%CI 26%-64%) of 29 HIV-infected subjects (p=0.0323). Among those with smear-positive pulmonary tuberculosis, TST was positive in 40 (100%; 95%CI 91%-100%) of 40 HIV-uninfected subjects compared with seven (54%; 95%CI 25%- 81%) of 13 HIV-infected subjects (p<0.0001), and QFTG was positive in 28(70%; 95%CI 53%-83%) of 40 HIV-uninfected subjects compared with three (23%; 95%CI 5%-54%) of 13 HIV-infected subjects (p=0.0029). Among medical inpatients at risk for latent tuberculosis infection, TST was positive in seven (50%) of 14 HIV-uninfected patients and three (19%) of 16 HIV-infected patients (p=0.0701) and QFTG was positive among two (14%) of 14 HIV-uninfected patients and three (19%) of 16 HIV-infected patients (p=0.7437).Conclusions: The presence of HIV co-infection was associated with a significant reduction in sensitivity of both the TST (p<0.0001) and QFTG (p=0.0029) for the diagnosis of active M.tuberculosis infection. The high proportion of indeterminate QFTG and lack of sensitivity, particularly among HIV-infected patients, may limit its applicability in settings like Tanzania. Larger studies in resource-poor settings are required.

Long-period grating fabricated by periodically tapering standard single-mode fiber

Author name used in this publication: Li-Yang ShaoAuthor name used in this publication: H. Y. TamAuthor name used in this publication: C. Lu2007-2008 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Templates for the Sunyaev-Zel'dovich Angular Power Spectrum

We present templates for the Sunyaev-Zel'dovich (SZ) angular power spectrum based on four models for the nonlinear gas distribution. The frequency-dependent SZ temperature fluctuations, with thermal (TSZ) and kinetic (KSZ) contributions, are calculated by tracing through a dark matter simulation, processed to include gas in dark matter halos and in the filamentary intergalactic medium. Different halo gas models are compared to study how star formation, energetic feedback, and nonthermal pressure support influence the angular power spectrum. The standard model has been calibrated to reproduce the stellar and gas fractions and X-ray scaling relations measured from low redshift clusters and groups. The other models illustrate the current theoretical and empirical uncertainties relating to properties of the intracluster medium. Relative to the standard model, their angular power spectra differ by approximately 50% (TSZ), 20% (KSZ), and 40% (SZ at 148 GHz) for l=3000, sigma_8=0.8, and homogeneous reionization at z=10. The angular power spectrum decreases in amplitude as gas mass and binding energy is removed through star formation, and as gas is pushed out to larger radii by energetic feedback. With nonthermal pressure support, less pressure is required to maintain hydrostatic equilibrium, thus reducing the thermal contribution to the SZ power. We also calculate the SZ templates as a function of sigma_8 and quantify this dependence. Assuming C_l is proprotional to (sigma_8/0.8)^alpha, the effective scaling index ranges from 7<alpha_tsz<9, 4.5<alpha_ksz<5.5, and 6.5<alpha_sz(148 GHz)<8 at l=3000 for 0.6<sigma_8<1. The template spectra are publicly available and can be used when fitting for the SZ contribution to the cosmic microwave background on arcminute scales.Comment: 14 pages, 10 figures, to be submitted to Ap

EM23, a natural sesquiterpene lactone, targets thioredoxin reductase to activate JNK and cell death pathways in human cervical cancer cells

Sesquiterpene lactones (SLs) are the active constituents of a variety of medicinal plants and found to have potential anticancer activities. However, the intracellular molecular targets of SLs and the underlying molecular mechanisms have not been well elucidated. In this study, we observed that EM23, a natural SL, exhibited anti-cancer activity in human cervical cancer cell lines by inducing apoptosis as indicated by caspase 3 activation, XIAP downregulation and mitochondrial dysfunction. Mechanistic studies indicated that EM23-induced apoptosis was mediated by reactive oxygen species (ROS) and the knockdown of thioredoxin (Trx) or thioredoxin reductase (TrxR) resulted in a reduction in apoptosis. EM23 attenuated TrxR activity by alkylation of C-terminal redox-active site Sec498 of TrxR and inhibited the expression levels of Trx/TrxR to facilitate ROS accumulation. Furthermore, inhibition of Trx/TrxR system resulted in the dissociation of ASK1 from Trx and the downstream activation of JNK. Pretreatment with ASK1/JNK inhibitors partially rescued cells from EM23-induced apoptosis. Additionally, EM23 inhibited Akt/mTOR pathway and induced autophagy, which was observed to be proapoptotic and mediated by ROS. Together, these results reveal a potential molecular mechanism for the apoptotic induction observed with SL compound EM23, and emphasize its putative role as a therapeutic agent for human cervical cancer.published_or_final_versio

Randomized controlled trial of letrozole, berberine, or a combination for infertility in the polycystic ovary syndrome

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