147 research outputs found
Strong Converse Exponent for Entanglement-Assisted Communication
We determine the exact strong converse exponent for entanglement-assisted
classical communication of a quantum channel. Our main contribution is the
derivation of an upper bound for the strong converse exponent which is
characterized by the sandwiched R\'enyi divergence. It turns out that this
upper bound coincides with the lower bound of Gupta and Wilde (Commun Math Phys
334:867--887, 2015). Thus, the strong converse exponent follows from the
combination of these two bounds. Our result has two implications. Firstly, it
implies that the exponential bound for the strong converse property of
quantum-feedback-assisted classical communication, derived by Cooney, Mosonyi
and Wilde (Commun Math Phys 344:797--829, 2016), is optimal. This answers their
open question in the affirmative. Hence, we have determined the exact strong
converse exponent for this problem as well. Secondly, due to an observation of
Leung and Matthews, it can be easily extended to deal with the transmission of
quantum information under the assistance of entanglement or quantum feedback,
yielding similar results. The above findings provide, for the first time, a
complete operational interpretation to the channel's sandwiched R\'enyi
information of order .Comment: V2: minor changes, presentation improve
Recent developments on catalytic membrane for gas cleaning
Β© 2019 Elsevier B.V. Catalytic membrane, a novel membrane separation technology that combines catalysis and separation, exhibits significant potential in gas purification such as formaldehyde, toluene and nitrogen oxides (NOx). The catalytic membrane can remove solid particles through membrane separation and degrade gaseous pollutants to clean gas via a catalytic reaction to achieve green emissions. In this review, we discussed the recent developments of catalytic membranes from two aspects: preparation of catalytic membrane and its application in gas cleaning. Catalytic membranes are divided into organic catalytic membranes and inorganic catalytic membranes depending on the substrate materials. The organic catalytic membranes which are used for low temperature operation (less than 300 Β°C) are prepared by modifying the polymers or doping catalytic components into the polymers through coating, grafting, or in situ growth of catalysts on polymeric membrane. Inorganic catalytic membranes are used at higher temperature (higher than 500 Β°C). The catalyst and inorganic membrane can be integrated through conventional deposition methods, such as chemical (physical) vapor deposition and wet chemical deposition. The application progress of catalytic membrane is focused on purifying indoor air and industrial exhaust to remove formaldehyde, toluene, NOx and PM2.5, which are also summarized. Perspectives on the future developments of the catalytic membranes are provided in terms of material manufacturing and process optimization
Differential expressed genes in ECV304 Endothelial-like Cells infected with Human Cytomegalovirus
Background: Human cytomegalovirus (HCMV) is a virus which has the potential to alter cellular gene expression through multiple mechanisms.Objective: With the application of DNA microarrays, we could monitor the effects of pathogens on host-cell gene expression programmes in great depth and on a broad scale.Methods: Changes in mRNA expression levels of human endothelial-like ECV304 cells following infection with human cytomegalovirus AD169 strain was analyzed by a microarray system comprising 21073 60-mer oligonucleotide probes which represent 18716 human genes or transcripts.Results: The results from cDNA microarray showed that there were 559 differential expressed genes consisted of 471 upregulated genes and 88 down-regulated genes. Real-time qPCR was performed to validate the expression of 6 selected genes (RPS24, MGC8721, SLC27A3, MST4, TRAF2 and LRRC28), and the results of which were consistent with those from the microarray. Among 237 biology processes, 39 biology processes were found to be related significantly to HCMV-infection. The signal transduction is the most significant biological process with the lowest p value (p=0.005) among all biological process which involved in response to HCMV infection.Conclusion: Several of these gene products might play key roles in virus-induced pathogenesis. These findings may help to elucidate the pathogenic mechanisms of HCMV caused diseases.Keywords: Human cytomegalovirus, microarray, Gene expression profiling; infectomicsAfrican Health Sciences 2013; 13(4): 864 - 87
MicroRNA-223 Delivered by Platelet-Derived Microvesicles Promotes Lung Cancer Cell Invasion via Targeting Tumor Suppressor EPB41L3
Background: Patients with hematogenous metastatic lung cancer displayed significantly increased platelet count and aggregation compared to lung cancer patients without hematogenous metastasis. The mechanism underlying the correlation between the lung cancer hematogenous metastasis and platelet activation remains unknown. Results: In the present study, we explored the role of microRNA-223 (miR-223) derived from platelets in modulating lung cancer cell invasion. Our results demonstrated that platelets from NSCLC patients contain higher level of miR-223 than that from healthy subjects. The concentration of miR-223 in the platelet-secreted microvesicles (P-MVs) from NSCLC patients was also increased compared to that from healthy subjects. Incubation of human lung cancer A549 cells with P-MVs resulted in rapid delivery of miR-223 into A549 cells, in which platelet miR-223 targeted EPB41L3 and thus promoted A549 cell invasion. The effect of P-MVs on reducing EPB41L3 in A549 cells but promoting tumor cell invasion could be largely abolished by depletion of miR-223 via transfection with miR-223 antagomir. The role of EPB41L3 in inhibiting A549 cell invasion was further validated by directly downregulating EPB41L3 via transfecting cells with EPB41L3 siRNA or miR-223 mimic. Conclusions: Our study demonstrates for the first time that platelet-secreted miR-223 via P-MVs can promote lung cancer cell invasion via targeting tumor suppressor EPB41L3
Fine-Tuning the Energy Levels of a Nonfullerene Small-Molecule Acceptor to Achieve a High Short-Circuit Current and a Power Conversion Efficiency over 12% in Organic Solar Cells.
Organic solar cell optimization requires careful balancing of current-voltage output of the materials system. Here, such optimization using ultrafast spectroscopy as a tool to optimize the material bandgap without altering ultrafast photophysics is reported. A new acceptor-donor-acceptor (A-D-A)-type small-molecule acceptor NCBDT is designed by modification of the D and A units of NFBDT. Compared to NFBDT, NCBDT exhibits upshifted highest occupied molecular orbital (HOMO) energy level mainly due to the additional octyl on the D unit and downshifted lowest unoccupied molecular orbital (LUMO) energy level due to the fluorination of A units. NCBDT has a low optical bandgap of 1.45 eV which extends the absorption range toward near-IR region, down to β860 nm. However, the 60 meV lowered LUMO level of NCBDT hardly changes the Voc level, and the elevation of the NCBDT HOMO does not have a substantial influence on the photophysics of the materials. Thus, for both NCBDT- and NFBDT-based systems, an unusually slow (β400 ps) but ultimately efficient charge generation mediated by interfacial charge-pair states is observed, followed by effective charge extraction. As a result, the PBDB-T:NCBDT devices demonstrate an impressive power conversion efficiency over 12%-among the best for solution-processed organic solar cells
Some recent studies on hohlraum physics
Some of our recent studies on hohlraum physics are presented, mainly including simulation study on hohlraum physics experiments on SGIII prototype, the design of Au + U + Au sandwich hohlraum for ignition target, and an initial design of elliptical hohlraum and pertinent drive laser power in order to generate an ignition radiation profile
Nlrp2, a Maternal Effect Gene Required for Early Embryonic Development in the Mouse
Maternal effect genes encode proteins that are produced during oogenesis and play an essential role during early embryogenesis. Genetic ablation of such genes in oocytes can result in female subfertility or infertility. Here we report a newly identified maternal effect gene, Nlrp2, which plays a role in early embryogenesis in the mouse. Nlrp2 mRNAs and their proteins (βΌ118 KDa) are expressed in oocytes and granulosa cells during folliculogenesis. The transcripts show a striking decline in early preimplantation embryos before zygotic genome activation, but the proteins remain present through to the blastocyst stage. Immunogold electron microscopy revealed that the NLRP2 protein is located in the cytoplasm, nucleus and close to nuclear pores in the oocytes, as well as in the surrounding granulosa cells. Using RNA interference, we knocked down Nlrp2 transcription specifically in mouse germinal vesicle oocytes. The knockdown oocytes could progress through the metaphase of meiosis I and emit the first polar body. However, the development of parthenogenetic embryos derived from Nlrp2 knockdown oocytes mainly blocked at the 2-cell stage. The maternal depletion of Nlrp2 in zygotes led to early embryonic arrest. In addition, overexpression of Nlrp2 in zygotes appears to lead to normal development, but increases blastomere apoptosis in blastocysts. These results provide the first evidence that Nlrp2 is a member of the mammalian maternal effect genes and required for early embryonic development in the mouse
- β¦