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By adjusting the frequency of the cavity, we perform a microwave reflection measurement and directly probe the coherence and interference effects in a phase-sensitive Josephson parametric amplifier. We demonstrate the shift in the peak and the dip in the reflection spectra of the amplifier, which operates in the phase-sensitive mode. The behavior of the shift can be precisely controlled by tuning the pump power, the frequency of the cavity, and the relative phase between the incident signal and pump field. Theoretical simulations are in good agreement with the experimental results. These results provide an alternative way of controlling the parametric process by adjusting the frequency of the cavity.

We fabricate a microscale electromechanical system, in which a suspended superconducting membrane, treated as a mechanical oscillator, capacitively couples to a superconducting microwave resonator. As the microwave driving power increases, nonmonotonic dependence of the resonance frequency of the mechanical oscillator on the driving power has been observed. We also demonstrate the optical switching of the resonance frequency of the mechanical oscillator. Theoretical models for qualitative understanding of our experimental observations are presented. Our experiment may pave the way for the application of a mechanical oscillator with its resonance frequency controlled by the electromagnetic and/or optical fields, such as a microwave-optical interface and a controllable element in a superqubit-mechanical oscillator hybrid system.

AimTo determine the association between HLA-DRB1 haplotypes and risk of cervical cancer in unselected and samples from Chinese ethnicities.MethodsA comprehensive search for articles from their inception to April 1st, 2013 was conducted from PubMed, Medline, Elsevier Science, Springer Link, Cochrane Library database, China biology medical literature database (CBM),China National Knowledge Infrastructure (CNKI),VIP,and Chinese literature database(Wang fang). A total of 1596 patients with cervical cancer and 2048 controls from the 12 studies on the relationship between gene polymorphism of HLA-DRB l and cervical cancer were performed and data were analyzed and processed using Review Manager 5.0 and Stata 11.0.ResultsAmong the 13 family alleles, two (DRB1*03 and DRB1*08) were found to be negatively associated with cervical cancer in all studies or in Uighur subgroups, and two (DRB1*10 and DRB1*15) were positively associated with in all studies or in Uighur subgroups. Among the 25 specific alleles, six (DRB1*0301, *0403,*0404, *0803, *1312 and *1502) were associated with an increased risk cervical cancer in all studies. No significant association was established for other HLA-DRB1 family alleles and specific alleles. Ethnicity partially explained the race influence of DRB1*12, DRB1*14, DRB1*0301, DRB1*0403, DRB1*0404, DRB1*0803, DRB1*1312 and DRB1*1502 phenotypes.ConclusionOur results support the hypothesis that the HLA-DRB1 family alleles and specific alleles might influence the susceptibility or resistance to cervical cancer, suggesting that immune regulation may play a key role in this disease, although further investigations are still needed.

Hypoxia has been shown to increase the expression of a variety of proteins involved in iron homeostasis, including ceruloplasmin, transferrin, and transferring receptor. Divalent metal transporter 1 (DMT1) is a transmembrane protein that is important in divalent metal ion transport, in particular iron. Although previous studies have provided that DMT1 exon1A is regulated by hypoxia, little is known about the relationship between DMT1 exon1B and hypoxia. Hypoxia-inducible factor 1 (HIF-1) is a transcription factor which is stabilized when mammalian cells are subjected to hypoxia. In this study, we have identified a functional hypoxia-response element (HRE) at position of -327 to -323 (-ACGTG-) in DMT1 exon1B promoter using a combination of bioinformatics and biological approaches. Both the total cellular iron and ferrous uptake increased after hypoxia, decreased after DMT1 RNA interference. Reactive oxygen species (ROS) were also changed by +iron responsive element (IRE) DMT1 exon1B overexpression. These findings implicated DMT1 exon1B was a target gene for HIF-1. Hypoxia might affect cellular iron uptake through regulating the expression of DMT1. When iron was present in excess, cells might be damaged by the ROS production. © 2010 IUBMB IUBMB Life, 62(8): 629–636, 2010. [ABSTRACT FROM AUTHOR]

The per-O-acetyl-d-fucosyl bromide (9) was expediently prepared for C-6 deoxygenation of d-galactose in six steps in 32.5% yield. Employing phase transfer catalysis glycosylation (PTC), d-fucopyranosyl diphyllin (4), the analog of natural diphyllin glycoside, was synthesized by using 9 as the glycosyl donor in 67.1% in two steps. The product was identified by 1H NMR, 13C NMR, and HRMS. Its abilities to inhibit the growth of cancer cells in vitro also are discussed. [ABSTRACT FROM AUTHOR]

Using the diluted S1813 UV photoresist as a sacrificial layer, we successfully fabricate a superconducting suspended parallel-plate capacitor, in which the top layer of aluminum film acts as a membrane mechanical resonator. Together with a superconducting octagonal spiral inductor, this parallel-plate capacitor constitutes a superconducting microwave resonator. At mK temperature, the transmission characteristic and spectrum of the microwave resonator are measured. Sideband frequencies caused by the vibration of the membrane mechanical resonator are clearly demonstrated. By down-converting with a mixer, the dependence of fundamental frequency and its harmonics on the input microwave power are clearly demonstrated, which is consistent with the numerical simulation. [ABSTRACT FROM AUTHOR]