On solutions of matrix equation AXB + CYD = F

AbstractIn this paper, the matrix equation with two unknown matrices X, Y of form AXB + CYD = F is discussed. By applying the canonical correlation decomposition (CCD) of matrix pairs, we obtain expressions of the least-squares solutions of the matrix equation, and sufficient and necessary conditions for the existence and uniqueness of the solutions. We also derive a general form of the solutions. We also study the least-squares Hermitian (skew-Hermitian) solutions of equation AXAH + CYCH = F

Treatment of human hepatocellular carcinoma by the oncolytic herpes simplex virus G47delta

Background: Oncolytic herpes simplex virus (HSV) can replicate in and kill cancer cells while sparing the adjacent normal tissue. Hepatocellular carcinoma (HCC) is amongst the most common and lethal cancers, especially in Third World countries. In this study, the cytotoxicity of a third-generation oncolytic HSV, G47Δ, was investigated in different human HCC cell lines and in an immortalized human hepatic cell line. Additionally, subcutaneous models of HCC were established to evaluate the in vivo anti-tumor efficacy of G47Δ. Methods: The HepG2, HepB, SMMC-7721, BEL-7404, and BEL-7405 human HCC cell lines and the HL-7702 human hepatic immortalized cell lines were infected with G47Δ at different multiplicities of infection (MOIs). The viability of infected cells was determined, and the G47Δ replication was identified by X-gal staining for LacZ expression. Two subcutaneous (s.c.) HCC tumor models of HCC were also established in Balb/c nude mice, which were intratumorally(i.t.) treated with either G47Δ or mock virus. Tumor volume and mouse survival times were documented. Results: More than 95% of the HepG2, Hep3B,and SMMC-7721 HCC cells were killed on by day 5 after infection with a MOI’s of 0.01. For the HL-7702 human hepatic immortalized cells, 100% of the cells were killed on by day 5 after infection with a MOI’s of 0.01. The BEL-7404 HCC cell line was less susceptible with about 70% cells were killed by day 5 after infection with a MOI’s of 0.01. Whereas the BEL-7405 HCC cells were the least susceptible, with only 30% of the cells were killed. Both the SMMC-7721 and BEL-7404 cells form aggressive sc tumor models. G47Δ replicates in the tumors, such that most of the tumors regressed after the G47Δ-treatment, and treated tumor-bearing mice survived much longer than the control animals. Conclusions: G47Δ effectively kills human HCC cells and an immortalized hepatic cell line at low MOI. Intra-tumor injection of G47Δ can induce a therapeutic effect and prolong the survival of treated mice bearing SMMC-7721 and BEL-7404 subcutaneously (s.c.) tumors. Thus, G47Δ may be useful as a novel therapeutic agent for HCC

Immunization with Fc-based recombinant Epstein-Barr virus gp350 elicits potent neutralizing humoral immune response in a BALB/c mice model

Epstein-Barr virus (EBV) was the first human virus proved to be closely associated with tumor development, such as lymphoma, nasopharyngeal carcinoma (NPC) and EBV-associated gastric carcinoma. Despite many efforts to develop prophylactic vaccines against EBV infection and diseases, no candidates have succeeded in effectively blocking EBV infection in clinical trials. Previous investigations showed that EBV gp350 plays a pivotal role in the infection of B lymphocytes. Nevertheless, using monomeric gp350 proteins as antigens has not been effective in preventing infection. Multimeric forms of the antigen are more potently immunogenic than monomers, however the multimerization elements used in previous constructs are not approved for human clinical trials. To prepare a much-needed EBV prophylactic vaccine that is potent, safe and applicable, we constructed an Fc-based form of gp350 to serve as a dimeric antigen. Here we show that the Fc-based gp350 antigen exhibits dramatically enhanced immunogenicity compared to wild-type gp350 protein. The complete or partial gp350 ectodomain was fused with the mouse IgG2a Fc domain. Fusion with the Fc domain did not impair gp350 folding, binding to a conformation-dependent neutralizing antibody and binding to its receptor by ELISA and SPR. Specific antibody titers against gp350 were notably enhanced by immunization with gp350-Fc dimers compared to gp350 monomers. Furthermore, immunization with gp350-Fc fusion proteins elicited potent neutralizing antibodies against EBV. Our data strongly suggest that an EBV gp350 vaccine based on Fc fusion proteins may be an efficient candidate to prevent EBV infection in clinical applications. Please click Additional Files below to see the full abstract

Using Vaccinia virus as a model system to understand microtubule-based transport

Vaccinia virus is a great model system for studying the cell cytoskeleton as it efficiently hijacks both the actin and microtubule network during infection. Intracellular mature virions (IMV) are the first infectious form of the virus produced during replication and are released when the cell undergoes lysis. A subset of IMV undergo envelopment at the Golgi to become intracellular enveloped virions (IEV) which recruit kinesin-1 to undergo microtubule-based transport from their perinuclear site of assembly to the plasma membrane. Limited work indicates that IMV can also be transported on microtubules. However, we have little or no molecular understanding of how this is achieved. This understudied area of vaccinia virus cell biology is surprising given that IMV comprise the majority of infectious virions formed during infection. I have now used a combination of cell-based and in vitro approaches to gain insights into IMV motility. Unexpectedly, I found that IMV also recruit kinesin-1 to move on microtubules in infected cells, although at a much lower levels compared to IEV. Using CRISPR/Cas9 genome edited cells expressing endogenously GFP-tagged kinesin-1, I have determined the number of kinesin-1 motors on virions and find that IMV recruit on average ~50% fewer motors than IEV. Additionally, for the first time, I have shown that these motors remain stably attached to the virus for long periods without undergoing turnover. I have also reconstituted IMV motility on purified microtubules in vitro using extracts from infected cells. In this system, IMV virions are very processive, typically moving to the very ends of the microtubule. Using polarity-marked microtubules, I found that IMV are exclusively plus-end directed, moving at an average velocity of ~0.65 μm/s. Furthermore, there is near complete loss of IMV motility in vitro in the absence of kinesin-1. Consistent with this, there is also a defect in intracellular IMV spread in cells lacking kinesin-1. My observations now demonstrate that kinesin-1 transports IMV as well as IEV during vaccinia infection. Moreover, reconstitution of vaccinia virus microtubule-based motility in vitro provides a useful new tool to investigate kinesin-1 driven transport of IMV and IEV in a system that is both biochemically accessible and tuneable to the user requirements

Ultra-Wideband and Wide-Angle Perfect Solar Energy Absorber Based on Titanium and Silicon Dioxide Colloidal Nanoarray Structure

In this paper, we designed an ultra-wideband solar energy absorber and approved it numerically by the finite-difference time-domain simulation. The designed solar energy absorber can achieve a high absorption of more than 90% of light in a continuous 3.506 μm (0.596 μm–4.102 μm) wavelength range. The basic structure of the absorber is based on silicon dioxide colloidal crystal and Ti. Since the materials have a high melting point, the designed solar energy absorber can work normally under high temperature, and the structure of this solar energy absorber is simpler than most solar energy absorbers fabricated with traditional metal. In the entire wavelength band researched, the average absorption of the colloidal crystal-based solar energy absorber is as high as 94.3%, demonstrating an excellent performance under the incidence light of AM 1.5 solar spectrum. In the meantime, the absorption spectrum of the solar energy absorber is insensitive to the polarization of light. In comparison to other similar structures, our designed solar energy absorber has various advantages, such as its high absorption in a wide spectrum range and that it is low cost and easy to make

Influence of structural design parameters on seismic performance of shaped single-tower cable-stayed bridges

The geometry and stress state of special-shaped cable-stayed bridges are complicated, so there is no uniform conclusion on their seismic performance and damage mechanisms under random seismic excitation. In light of this, taking a single cable plane curved inclined single tower cable-stayed bridge as the background, this paper establishes a spatial finite element model and conducts structural dynamic characteristics and seismic response analysis. Based on this, taking the bending radius and tilt angle as design parameters, the sensitivity analysis of structural seismic response to design parameters is carried out. The analysis results show that the first 5 vibration modes of the bridge are mainly the lateral vibration of the tower and girder, as well as the vertical vibration of the girder. Besides, the vibration modes are dispersed, and there is no phenomenon where a certain vibration mode dominates.The seismic response of the middle part of the tower is subjected to a large bending moment under the action of seismic force. Sensitivity analysis of structural design parameters indicates that the tower tilt angle and radius of curvature affect the bending moment more than the axial force, and the seismic performance of bridge decreases with the increase of tower tilt angle

Finite-Key Analysis of 1-Decoy Method Quantum Key Distribution with Intensity Fluctuation

The decoy state quantum key distribution (QKD) protocol is proven to be an effective strategy against the photon number splitting attack. It was shown that the 1-decoy state protocol, easier to implement in the practical QKD system, outperforms the 2-decoy state protocol for block sizes of up to 108 bits. How intensity fluctuations influence the performance of the 1-decoy state protocol with finite resources remains a pending issue. In this paper, we present a finite-key analysis of the 1-decoy state protocol with intensity fluctuations and obtain the secret key rate formula about intensity fluctuations. Our numerical simulation results show that the stronger the intensity fluctuations, the lower the secret key rate for a small data block size of a few bits. Our research can provide theoretical implications for the selection of data size in the QKD system with intensity fluctuations

Insight into the Vibrational and Thermodynamic Properties of Layered Lithium Transition-Metal Oxides LiMO₂ (M = Co, Ni, Mn): A First-Principles Study

Evaluation of the finite-temperature thermodynamic properties of the electrode materials generally helps to accurately describe the performance of Li-ion battery (LIBs). To know the characteristics of the layered lithium transition-metal oxides LiMO₂ (M = Co, Ni, Mn) comprehensively, herein, the vibrational and related thermodynamic quantities of these electrode materials are investigated by using density functional perturbation theory (DFPT). Local density approximation (LDA) and generalized gradient approximation with the Hubbard model correction (GGA+<i>U</i>) yield similar results, either for the phonon dispersion or for the thermodynamic functions. Among the three layered lithium transition-metal oxides, the vibrational and thermodynamic properties of LiNiO₂ is more close to that of LiMnO₂, while relatively far away from that of LiCoO₂, due to the same crystal structure of LiNiO₂ and LiMnO₂, which is different from that of LiCoO₂. In addition, the corrections of average intercalation voltage as a function of temperature for Li_0.75CoO₂ and Li_0.5CoO₂ are evaluated when considering the contribution of vibrational entropy. Since our theoretical results for LiCoO₂ agree well with those from experiments, we can provide the reliable thermodynamic data for the layered lithium transition-metal oxides