An emerging antibacterial nanovaccine for enhanced chemotherapy by selectively eliminating tumor-colonizing bacteria

Fusobacterium nucleatum(F.nucleatum),an oral anaerobe,is prevalent in colorectal cancer and is closely related to increased cancer cell growth,metastasis,and poor treatment outcomes.Bacterial vaccines capable of selectively eliminating bacteria present a promising approach to targeting intratumor F.nucleatum,thereby enhancing cancer treatment.Although adjuvants have been employed to enhance the immune response,the vaccine’s effectiveness is constrained by inadequate T-cell activation necessary for eradicating intracellular pathogens.In this study,we developed a minimalistic,biomimetic nanovaccine by integrating highly immunostimulatory adjuvant cholesterol-modified CpG oligonucleotides into the autologously derived F.nucleatum membranes.Compared to the traditional vaccines consisting of inactivated bacteria and Alum adjuvant,the nanovaccine coupled with bacterial membranes and adjuvants could remarkably improve multiple antigens and adjuvant co-delivery to dendritic cells,maximizing their ability to achieve effective antigen presentation and strong downstream immune progress.Notably,the nanovaccine exhibits outstanding selective prophylactic and therapeutic effects,eliminating F.nucleatum without affecting intratumoral and gut microbiota.It significantly enhances chemotherapy efficacy and reduces cancer metastasis in F.nucleatum-infected colorectal cancer.Overall,this work represents the rational application of bacterial nanovaccine and provides a blueprint for future development in enhancing the antitumor effect against bacterial-infected cancer.

An innovative inertial parameters identification method for non-cooperative space targets based on electrostatic interaction

Inertial characteristics of non-cooperative targets are crucial for space capture and sub-sequent on-orbit servicing.Previous methods for identifying inertial parameters involve proximity operations,which are associated with the risk of collision with non-cooperative targets.This paper introduces a long-range,contactless method for identifying the inertial parameters of a non-cooperative target during the pre-capture phase.Specifically,electrostatic interaction is used as an external excitation to alter the target's motion.A force estimation algorithm that uses measure-ments from visual and potential sensors is proposed to estimate the electrostatic interaction and eliminate the need for force sensors.Furthermore,a recursive estimation-identification framework is presented to concurrently estimate the coupled motion state,weak electrostatic interaction,and inertial parameters of the target.The simulation results show that the proposed method extends the identification distance to 170 times that of the previous method while maintaining high identifica-tion precision forall parameters.

Transient Voltage Support Strategy of Grid-forming Medium Voltage Photovoltaic Converter in the LCC-HVDC System

The participation of photovoltaic(PV)plants in supporting the transient voltage caused by commutation failure in the line-commutated-converter-based high voltage direct current(LCC-HVDC)system is of great significance,as it can enhance the DC transmission ability.However,it is found that the gridfollowing(GFL)PV converters face the problem of mismatch between reactive power response and transient voltage characteristic when the voltage converts from low voltage to overvoltage,further aggravating the overvoltage amplitude.Thus,this article proposes a transient voltage support strategy based on the gridforming(GFM)medium voltage PV converter.The proposed strategy takes the advantage of the close equivalent electrical distance between the converter and grid,which can autonomously control the converter terminal voltage through GFM control with adaptive voltage droop coefficient.The simulation results show that the proposed strategy can ensure the output reactive power of the PV converter quickly matches the transient voltage characteristic at different stages,indicating that the proposed strategy can effectively support the transient voltage.

A Continuous Fault Ride-through Scheme for DFIGs Under Commutation Failures in LCC-HVDC Transmission Systems

Experimental and theoretical studies have confirmed that,relative to a one-shot voltage fault,a doubly-fed induction generator(DFIG)will suffer a greater transient impact during continuous voltage faults.This paper presents the design and application of an effective scheme for DFIGs when a commutation failure(CF)occurs in a line-commutated converter based high-voltage direct current(LCC-HVDC)transmission system.First,transient demagnetization control without filters is proposed to offset the electromotive force(EMF)induced by the natural flux and other low-frequency flux components.Then,a rotor-side integrated impedance circuit is designed to limit the rotor overcurrent to ensure that the rotor-side converter(RSC)is controllable.Furthermore,coordinated control of the demagnetization and segmented reactive currents is implemented in the RSC.Comparative studies have shown that the proposed scheme can limit rotor fault currents and effectively improve the continuous fault ride-through capability of DFIGs.

Enhancing HVRT Capability of DFIG-based Wind Farms Using Cooperative Rotor-side SMES Considering the Blocking Fault of LCC-HVDC System

Line-commutated converter based high voltage direct current(LCC-HVDC)has been applied for transferring bulk power from wind farms to load centers through long distances in many countries.When the blocking fault of the LCC-HVDC system occurs,the surplus reactive power accumulated at the sending end will lead to an overvoltage,thus causing the discon・nection of the wind turbines.To maintain the reliable connection of wind turbines and ensure the stability of the power system,this paper introduces a superconducting magnetic energy storage(SMES)unit to connect in parallel with the rotor side of the doubly fed induction generator(DFIG).By controlling the energy side converter and rotor side converter to inject demagnetizing current and reactive current into the rotor,the proposed scheme can effectively stabilize key parameters of the wind turbine and provide desirable reactive power support,showing a favorable high voltage ride through(HVRT)performance.Several cases based on PSCAD/EMTDC&MATLAB/Simuiink co-simulation together with economic analysis are conducted to demonstrate the feasibility and superiority of the proposed scheme on enhancing HVRT capability of DFIG-based wind farms.

Perceived Utility of Premium Power by High-tech Manufacturers

The valuation of premium power based on perceived utility(PU,i.e.,perceived effectiveness or satisfaction degree of customers)and their willingness to pay has been researched for years.One of the remaining challenges is the accurate evaluation of PU.PU is the foundation of premium power evaluation,and it is essential for the decision-making process of investments on premium power by high-tech manufacturers(HTMs).This paper presents a framework to effectively evaluate PU.In this framework,factors influencing PU were classified to be quantitative and qualitative.An indication system(IS)was then constructed based on those influencing factors.Finally,PU was evaluated by the IS,considering psychological perception and decision-making behavior of HTMs.The effectiveness of the proposed PU-evaluation framework was demonstrated through field case studies.

Event-Triggered-Backstepping-Based Parallel Approaching Guidance Method for Maneuvering Target Interception

In order to achieve a straight ballistic trajectory of missile and reduce the update frequency of the missile normal acceleration for the interception of maneuvering target,a backstepping-based parallel approaching guidance method is designed with nonlinear disturbance observer(NDO)technique and event-triggered(ET)mechanism in this paper.In order to suppress the adverse e®ect of target maneuver,the NDO is designed to estimate the target maneuvering acceleration.Then,the NDO-based backstepping method is used to obtain the normal acceleration of missile and realize the parallel approaching guidance.In order to reduce the update frequency of missile normal acceleration,the ET mechanism is employed in the parallel approaching guidance method.If the missile trajectory is relatively straight,the normal acceleration of missile remains unchanged.On the contrary,if the missile trajectory is not straight,the normal acceleration of missile is updated to make the missile trajectory straight.In this way,the ET-based parallel approaching guidance can be obtained.Furthermore,a determined method for the initial missile°ight-path angle is proposed to keep the normal acceleration of missile at zero in the initial stage of interception.Besides,Lyapunov stability analysis method is used to prove that all signals in the closed-loop guidance system are uniformly ultimately bounded.Finally,simulation results show the e®ectiveness of the proposed guidance method.