•A new soft robotic gripper with variable stiffness was designed. Its uniqueness lies in the structural decoupling of the deformation actuator for bending and the variable stiffness mechanism of the ...soft robotic gripper.•Based on the Cosserat theory, a grasping force model is built for the proposed soft robotic gripper with variable stiffness.•A series of experimental tests and simulations on the grasping force of the soft robotic gripper are investigated to discuss the modeling properties.
The purpose of this research is to present a grasping force model for a soft robotic gripper with variable stiffness. The soft robotic gripper was made of shape memory alloys (SMAs) with contraction and variable stiffness properties. A variable stiffness mechanism with embedded sets of SMA fibers was developed; however, the response characteristics of its backbone did not comply with the constant-curvature model when it was subjected to complex forces/torques, such as gravity, grasping forces and driving torques. In this case, the Cosserat theory was used to implement real-time computations of the grasping force of the soft robotic gripper that was subjected to complex forces. Finally, a series of tests were conducted on the grasping force of the soft finger and the gripper. The elicited results showed that the grasping force is related to the stiffness and to the object's offset and friction coefficient. Moreover, experimental results showed that the grasping force of the soft robotic gripper increased by 48.7% when the Young's modulus of the SMA-2 wires increased from 25 GPa to 48 GPa.
•A review specifically summarising PD-1 disrupted CAR T cells as cancer therapeutics.•Antitumor activity of CAR T cells can be enhanced significantly by PD-1 disruption.•This new combination strategy ...could be the new hope for solid tumor treatment.•Increasing number of clinical trials on these CAR T cells have been commenced.•Future prospects & challenges of this new combination strategy are discussed.
Unprecedented efficacy of chimeric antigen receptor (CAR) T cell therapy in the treatment of hematologic malignancies brings new hope for patients with many cancer types including solid tumors. However, the challenges for CAR-T cell therapy in eradicating solid tumors are immense. To overcome these seemingly intractable hurdles, more “powerful” CAR-T cells with enhanced antitumor efficacy are required. Emerging data support that the anti-tumor activity of CAR-T cells can be enhanced significantly without evident toxicity through simultaneous PD-1 disruption by genome editing. This review focuses on the current progress of PD-1 gene disrupted CAR-T cells in cancer therapy. Here we discuss key rationales for this new combination strategy and summarize the available pre-clinical studies. An update is provided on human clinical studies and available registered cancer clinical trials using CAR-T cells with PD-1 disruption. Future prospects and challenges are also discussed.
Some light materials, such as hollow sphere composite (HSC), carbon fiber reinforced plastic (CFRP), and aluminum alloy (AA), are currently used in the design of lightweight robotic arms. However, ...the high cost limit the use of HSC, the CFRP has a relatively low cost but poor processing property, and the AA has good processing property but relatively high density. To make up respective shortcomings, this study focuses on the design issues of lightweight robotic arms by using two kinds of materials. Based on the CFRP and AA, a hybrid structure design approach is proposed to minimize the total mass of the lightweight robotic arms with CFRP/AA hybrid structure. To accomplish the objective, structural dimensions and layer parameters in hybrid structures are parameterized as design variables subject to the strength, stiffness, and dynamic constraints. Moreover, the bonding strength of the interaction surfaces between CFRP and AA parts is also considered on the basis of the cohesive zone model (CZM). In optimization design, the ABAQUS and elitist non-dominated sorting genetic algorithm (NSGA-II) in modeFRONTIER utilizing the Python script are respectively employed for the structural analyses and iteration calculation. Finally, a design example and an experimental prototype are provided to validate the proposed method and compare with the previous AA prototype in mass with a reduction of 24.32%.
Fucoidans, discovered in 1913, are fucose-rich sulfated polysaccharides extracted mainly from brown seaweed. These versatile and nontoxic marine-origin heteropolysaccharides have a wide range of ...favorable biological activities, including antitumor, immunomodulatory, antiviral, antithrombotic, anticoagulant, antithrombotic, antioxidant, and lipid-lowering activities. In the early 1980s, fucoidans were first recognized for their role in supporting the immune response and later, in the 1990s, their effects on immune potentiation began to emerge. In recent years, the understanding of the immunomodulatory effects of fucoidan has expanded significantly. The ability of fucoidan(s) to activate CTL-mediated cytotoxicity against cancer cells, strong antitumor property, and robust safety profile make fucoidans desirable for effective cancer immunotherapy. This review focusses on current progress and understanding of the immunopotentiation activity of various fucoidans, emphasizing their relevance to cancer immunotherapy. Here, we will discuss the action of fucoidans in different immune cells and review how fucoidans can be used as adjuvants in conjunction with immunotherapeutic products to improve cancer treatment and clinical outcome. Some key rationales for the possible combination of fucoidans with immunotherapy will be discussed. An update is provided on human clinical studies and available registered cancer clinical trials using fucoidans while highlighting future prospects and challenges.
Traditionally, synchronous motion among multi-module permanent magnet linear synchronous motors (PMLSM) has been achieved by adopting independent power supply and control. This method, however, ...requires multiple drivers and has control time delays. This paper proposes a novel approach to overcome these drawbacks, in which the windings of each module connect in series. Aiming at this electrical connection, we conduct research on electromagnetic and synchronous characteristics. Firstly, a two-module PMLSM is created as a case. Secondly, accurate mathematical models considering coupling inductance for this novelty structure are established, which are essential to driving control. The synchronous characteristics of the two-module are then compared with the independent control of each module. Furthermore, this comparison is conducted under both external and no external disturbance. Finally, experimental results verify the correctness of mathematical models, and reveal that this novel technique could eliminate control time delay and acquire better anti-disturbance performance between the two-module.
Dependent Quantization (DQ) is a new quantization tool introduced in the Versatile Video Coding (VVC) standard. While it provides better rate-distortion calculation accuracy, it also increases the ...computational complexity and hardware cost compared to the widely used scalar quantization. To address this issue, this paper proposes a parallel-dependent quantization hardware architecture using Verilog HDL language. The architecture preprocesses the coefficients with a scalar quantizer and a high-frequency filter, and then further segments and processes the coefficients in parallel using the Viterbi algorithm. Additionally, the weight bit width of the rate-distortion calculation is reduced to decrease the quantization cycle and computational complexity. Finally, the final quantization of the TU is determined through sequential scanning and judging of the rate-distortion cost. Experimental results show that the proposed algorithm reduces the quantization cycle by an average of 56.96% compared to VVC's reference platform VTM, with a Bjøntegaard delta bit rate (BDBR) loss of 1.03% and 1.05% under the Low-delay P and Random Access configurations, respectively. Verification on the AMD FPGA development platform demonstrates that the hardware implementation meets the quantization requirements for 1080P@60Hz video hardware encoding.
Multi-segment-primary (MSP) ironless Permanent Magnet Linear Synchronous Machine (PMLSM) can be widely applied in long primary, long stroke, and heavy load applications. Therefore, an accurate ...armature reaction field analysis is very important to control this novel topology motor. In order to simplify the research process, a two-segment-primary (TSP) ironless PMLSM in this article was proposed as the smallest unit. The analytical models of the armature reaction field of the motor based on the subdomain method (SDM) were established considering the finite length of the segment-primary (SP) and the interval distance between the TSP. Then, the coupling effect between the TSP and the end effect of the TSP on the armature reaction field were quantitatively analyzed. Furthermore, the coupling inductance between the TSP can be analytically calculated, which is influenced by the coupling effect. To validate the effectiveness of the proposed models, a prototype of the 24s/28p TSP ironless PMLSM was manufactured and tested. It was shown that the proposed models match well with the simulated and experimental results. As well, the maximum variation rate of the end coupling inductance was about 50.13%.
This article presents a unified design for lightweight robotic arms based on a unified description of structure and drive trains. In the unified design, the drive trains and structural dimensions are ...parameterized as design variables, and a major objective minimizes the total mass of robotic arms satisfying the constraint conditions and design criteria. To implement the optimization problem, a mapping relationship between mass and torque of drive trains is introduced as their power–density curves, which enable a unified description of structure and drive trains combining with the dynamics of robotic arms. In this implementation of unified design, there are two modules: structure optimization and drive trains design. The finite element method with nonlinear programming by quadratic Lagrange algorithm is adopted to implement the structure optimization. Moreover, the dynamic analysis in MSC ADAMS is achieved to design the drive trains of robotic arms. This method could uniformly evaluate all components of robotic arms in mass and continuously search the global optimal results. Finally, a design example on this unified design is compared with a referenced design to illustrate the validity and advantage of the proposed scheme.
Hydrogels developed as stimuli-responsive drug delivery systems (DDSs) are increasingly concerned research focus in many fields such as chemistry, functional materials and biomedicine. Herein, we ...report the fabrication, characterization and drug release property of new gelatin composite hydrogels by using biocompatible gelatin and the doxorubicin (DOX)-loaded micelles of a redox-responsive side-chain ferrocene (Fc)-containing amphiphilic diblock copolymer PNFc-b-PNTEG (Fig. 1). The self-assembly method was firstly adopted to prepare the DOX-loaded micelles of PNFc-b-PNTEG with oxidation-sensitive release property, and the DOX-loaded gelatin composite hydrogels were then successfully fabricated by using blending and soaking methods, respectively. The formed hydrogels were characterized by many techniques including scanning electron microscope, energy-dispersive spectroscopy, differential scanning calorimetry, thermogravimetry and swelling test. The successful encapsulation of the DOX-containing micelles in the gelatin matrix was demonstrated, and the prepared composite hydrogels exhibited improved thermal stability, faster swelling speed and higher swelling ratios. The oxidation-triggered controlled in vitro release of DOX from the composite hydrogels was confirmed by using FeCl3 at different concentrations as an oxidizing agent. The composite hydrogels could act as excellent solid carriers to guarantee the sustained-release effect of DOX, and it is feasible to keep the DOX molecules with high concentration at the specific site for a long period (20 days or so). Thus, the present composite hydrogels are anticipated to be good candidates as redox-responsive DDSs.
A CMOS technology compatible non-volatile SRAM (cNV SRAM) is proposed in this paper to achieve energy efficient on-chip memory. cNV SRAM works as conventional 8T SRAM to keep high speed in work mode; ...in sleep mode, it backs up the data in its NV component and switches off the power supply, thereby minimizing the leakage energy without data loss. The circuit- and architectural- level implementation schemes of cNV SRAM are developed considering multiple key performance parameters including energy dissipation, access time, write time, noise margin, layout area, restoration time, and injection charges. Simulation results on SPEC 2000 benchmark suite demonstrate that cNV SRAM realizes 86 percent energy savings on average with negligible performance impact and small hardware overhead as compared to conventional SRAM. Finally, the impact of the sleep time and memory size on the effectiveness of cNV SRAM is analyzed in detail and it shows that cNV SRAM is particularly effective to implement large on-chip memories with long idle time.
PDF
