Achieving Covert Communication With A Probabilistic Jamming Strategy

In this work, we consider a covert communication scenario, where a transmitter Alice communicates to a receiver Bob with the aid of a probabilistic and uninformed jammer against an adversary warden's detection. The transmission status and power of the jammer are random and follow some priori probabilities. We first analyze the warden's detection performance as a function of the jammer's transmission probability, transmit power distribution, and Alice's transmit power. We then maximize the covert throughput from Alice to Bob subject to a covertness constraint, by designing the covert communication strategies from three different perspectives: Alice's perspective, the jammer's perspective, and the global perspective. Our analysis reveals that the minimum jamming power should not always be zero in the probabilistic jamming strategy, which is different from that in the continuous jamming strategy presented in the literature. In addition, we prove that the minimum jamming power should be the same as Alice's covert transmit power, depending on the covertness and average jamming power constraints. Furthermore, our results show that the probabilistic jamming can outperform the continuous jamming in terms of achieving a higher covert throughput under the same covertness and average jamming power constraints

Lnc-PKD2-2-3/miR-328/GPAM ceRNA Network Induces Cholangiocarcinoma Proliferation, Invasion and 5-FU Chemoresistance

PurposeOur previous study observed that long non-coding RNA PKD2-2-3 (lnc-PKD2-2-3) is related to advanced tumor features and worse prognosis in cholangiocarcinoma (CCA). Then, this study aimed to further explore the linkage between lnc-PKD2-2-3, miR-328, and GPAM, as well as their effects on regulating CCA viability, mobility, and chemosensitivity.MethodsLnc-PKD2-2-3, miR-328, and GPAM expression in 30 pairs of CCA tumor and adjacent tissues, as well as in CCA cell lines, were determined. Two CCA cell lines (HuCCT1 and TFK1) were transfected by lnc-PKD2-2-3 overexpression plasmid, lnc-PKD2-2-3 siRNA, miR-328 inhibitor, and GPAM siRNA alone or in combination, followed by cell proliferation, apoptosis, invasion, and 5-FU chemosensitivity detection. Besides, xenograft mice were established for validation.ResultsLnc-PKD2-2-3 and GPAM were higher, whereas miR-328 was lower in CCA tissues versus adjacent tissues and also in CCA cell lines versus control cells; meanwhile, they were correlated with each other (all P <0.05). Lnc-PKD2-2-3 knockdown decreased CCA cell proliferation, invasion, and increased apoptosis (all P <0.05), but lnc-PKD2-2-3 overexpression exhibited the opposite and weaker effect. MiR-328 knockdown induced CCA cell proliferation and invasion and also attenuated the effect of lnc-PKD2-2-3-knockdown in these functions (all P <0.05). Subsequently, GPAM knockdown reduced CCA cell proliferation and invasion and also weakened the effect of miR-328-knockdown in these functions (all P <0.05). Additionally, lnc-PKD2-2-3 positively regulated GPAM while negatively regulating miR-328. MiR-328 negatively modified GPAM in CCA cells. Luciferase gene reporter assays verified that lnc-PKD2-2-3 directly bound miR-328 and miR-328 directly bound GPAM. Finally, the lnc-PKD2-2-3/miR-328/GPAM network also regulated the 5-FU chemosensitivity of CCA cells. In vivo experiments further revealed that lnc-PKD2-2-3 overexpression promoted tumor volume and weight but repressed tumor apoptosis in xenograft mice; meanwhile, it increased GPAM expression but decreased miR-328 expression (all P <0.05). Conversely, lnc-PKD2-2-3 knockdown exhibited the opposite effects (all P <0.05).ConclusionLnc-PKD2-2-3/miR-328/GPAM ceRNA network promotes CCA proliferation, invasion, and 5-FU chemoresistance

Retrograde venous coil embolization prior to transarterial chemoembolization in hepatocellular carcinoma with arterio-hepatic venous shunts

PURPOSEThis study explored the clinical efficacy of transcatheter retrograde shunt occlusion with coils to prevent pulmonary oil or particle embolization prior to transarterial chemoembolization (TACE) in patients with artero-hepatic venous shunts (AHVS) secondary to hepatocellular carcinoma (HCC).METHODSFrom July 2017 to January 2021, 6 patients with advanced, unresectable HCC were found to have an AHVS by hepatic arteriography at the time of attempted TACE. The AHVS was embolized retrogradely with metal coils through a transfemoral or transjugular venous approach. After venous embolization and confirmation of the absence of the AHVS, TACE was performed using an emulsion of iodized oil and doxorubicin or drug-eluting beads. Follow-up computed tomography (CT) was performed within 1 month after the first TACE to evaluate the results and complications.RESULTSHepatic angiography after venous embolization showed that AHVS had utterly disappeared in all patients during the operation. The immediate technical success of the retrograde venous embolization was 100%. The AHVS had disappeared entirely during the follow-up period through triple-phase enhancement CT scanning. According to the modified response evaluation criteria in solid tumors, TACE in all 6 patients had a disease control response rate of 100% (6/6) with complete response in 2 patients and partial response in 4 patients. One patient died during the 6-month follow-up, and the other 5 were still alive. No complications related to pulmonary embolism occurred.CONCLUSIONRetrograde venous coil embolization of AHVS via the draining hepatic vein appears to be a safe, feasible, and effective treatment to allow TACE treatment without pulmonary embolic events. This approach appears to provide better tumor control and effectively decreases the occurrence of pulmonary embolism

Exploring the Potential of Integrated Optical Sensing and Communication (IOSAC) Systems with Si Waveguides for Future Networks

Advanced silicon photonic technologies enable integrated optical sensing and communication (IOSAC) in real time for the emerging application requirements of simultaneous sensing and communication for next-generation networks. Here, we propose and demonstrate the IOSAC system on the silicon nitride (SiN) photonics platform. The IOSAC devices based on microring resonators are capable of monitoring the variation of analytes, transmitting the information to the terminal along with the modulated optical signal in real-time, and replacing bulk optics in high-precision and high-speed applications. By directly integrating SiN ring resonators with optical communication networks, simultaneous sensing and optical communication are demonstrated by an optical signal transmission experimental system using especially filtering amplified spontaneous emission spectra. The refractive index (RI) sensing ring with a sensitivity of 172 nm/RIU, a figure of merit (FOM) of 1220, and a detection limit (DL) of 8.2*10-6 RIU is demonstrated. Simultaneously, the 1.25 Gbps optical on-off-keying (OOK) signal is transmitted at the concentration of different NaCl solutions, which indicates the bit-error-ratio (BER) decreases with the increase in concentration. The novel IOSAC technology shows the potential to realize high-performance simultaneous biosensing and communication in real time and further accelerate the development of IoT and 6G networks.Comment: 11pages, 5 figutre

Heat-Shock Protein 90 Promotes Nuclear Transport of Herpes Simplex Virus 1 Capsid Protein by Interacting with Acetylated Tubulin

Although it is known that inhibitors of heat shock protein 90 (Hsp90) can inhibit herpes simplex virus type 1 (HSV-1) infection, the role of Hsp90 in HSV-1 entry and the antiviral mechanisms of Hsp90 inhibitors remain unclear. In this study, we found that Hsp90 inhibitors have potent antiviral activity against standard or drug-resistant HSV-1 strains and viral gene and protein synthesis are inhibited in an early phase. More detailed studies demonstrated that Hsp90 is upregulated by virus entry and it interacts with virus. Hsp90 knockdown by siRNA or treatment with Hsp90 inhibitors significantly inhibited the nuclear transport of viral capsid protein (ICP5) at the early stage of HSV-1 infection. In contrast, overexpression of Hsp90 restored the nuclear transport that was prevented by the Hsp90 inhibitors, suggesting that Hsp90 is required for nuclear transport of viral capsid protein. Furthermore, HSV-1 infection enhanced acetylation of α-tubulin and Hsp90 interacted with the acetylated α-tubulin, which is suppressed by Hsp90 inhibition. These results demonstrate that Hsp90, by interacting with acetylated α-tubulin, plays a crucial role in viral capsid protein nuclear transport and may provide novel insight into the role of Hsp90 in HSV-1 infection and offer a promising strategy to overcome drug-resistance

Quasi-static and dynamic interfacial evaluations of plasma functionalized carbon nanotube fiber

Carbon nanotube (CNT) fibers composed of well-oriented and twisted CNT bundles are desirable as a strong and lightweight reinforcement for the high-performance composites. Herein, CNT fibers were functionalized by atmospheric pressure helium/oxygen plasma to build up the sufficient fiber/matrix interfacial bonding. The micro-bond test (quasi-static test) and electrical resistance measurement under cyclic loading (dynamic test) were carried out to evaluate the interfacial properties between CNT fiber and epoxy resin. The results illustrated 84.6% improvement in the interfacial shear strength (IFSS) of the functionalized CNT fiber and epoxy from 17.37 MPa to 32.08 MPa, since the generated oxygenic groups and roughed morphology on CNT fiber surface. Moreover, the linear and repeatable gauge factors (between 1.1 and 1.4) of the functionalized CNT fiber embedded in epoxy under dynamic cyclic loading demonstrated their good interfacial bonding as well. In addition, the tensile strength of the functionalized CNT fiber showed 49.5% increment. Our study for the first time reveals the interface interaction in a fiber-matrix system to provide the direct evidence for the interfacial enhancement of the plasma functionalized CNT fiber. The interface-enhanced CNT fiber can be generally applied in composites with much improved mechanical and electrical performance.</p

Synergistic effect of CNT films impregnated with CNT modified epoxy solution towards boosted interfacial bonding and functional properties of the composites

Carbon nanotubes thin films (CNTf) in polymers should demonstrate excellent mechanical, thermal and electrical properties. However, such anticipated properties are hardly possible due to a number of factors. For example, the weak bonding of CNTf with polymers at the interface which results in easy delamination and deteriorated properties of the CNTf/polymer composites. More still, the declined conductivity of composites highly contributed by the insulating polymers. Herein, an approach to solve the mentioned problems is reported which briefly involved first modifying the polymer (epoxy resin) with the CNT in controlled percentages, and then introducing the CNTf to the modified epoxy solution which synergistically created a new CNT-to-CNT interphase and interlocked interactions, hence, presenting enhanced peeling (74.38%) and tensile (164.76%) strength in modified composites as compared to the unmodified CNTf/epoxy composites. Moreover, the strain sensing, conductivity, and temperature responses of the composites were also significantly improved as required in various high-performance composites.</p

Instantaneous sediment transport model for asymmetric oscillatory sheet flow

<div><p>On the basis of advanced concentration and velocity profiles above a mobile seabed, an instantaneous analytical model is derived for sediment transport in asymmetric oscillatory flow. The applied concentration profile is obtained from the classical exponential law based on mass conservation, and asymmetric velocity profile is developed following the turbulent boundary layer theory and the asymmetric wave theory. The proposed model includes two parts: the basic part that consists of erosion depth and free stream velocity, and can be simplified to the total Shields parameter power 3/2 in accordance with the classical empirical models, and the extra vital part that consists of phase-lead, boundary layer thickness and erosion depth. The effects of suspended sediment, phase-lag and asymmetric boundary layer development are considered particularly in the model. The observed instantaneous transport rate proportional to different velocity exponents due to phase-lag is unified and summarised by the proposed model. Both instantaneous and half period empirical formulas are compared with the developed model, using extensive data on a wide range of flow and sediment conditions. The synchronous variation in instantaneous transport rate with free stream velocity and its decrement caused by increased sediment size are predicted correctly. Net transport rates, especially offshore transport rates with large phase-lag under velocity skewed flows, which existing instantaneous type formulas failed to predict, are predicted correctly in both direction and magnitude by the proposed model. Net sediment transport rates are affected not only by suspended sediment and phase-lag, but also by the boundary layer difference between onshore and offshore.</p></div