Multi-stable mechanical metamaterials with unprecedented mechanical/physical properties have attracted great interests due to their functional applications for advanced materials and devices. ...However, the original curved/tilted bistable snapping segments in most of those existing multi-stable mechanical metamaterials cause unequal bistability/multi-stability. The relative thicker supporting segments can't provide complete constraints at the end of snapping segments using single parent material. To achieve completely symmetric bistable/multi-stable mechanism, an innovative design strategy is proposed based on interlocking assembly method with multi-materials and compressed buckled snapping segments for bistable units. Theoretical analysis, numerical simulations and experimental verifications are used to show completely symmetric bistability/multi-stability with negative stiffness. The multi-stable mechanical metamaterials have robust shape-reconfigurability and zero Poisson's ratio with large recoverable deformation. Geometric and material gradients design are carried out to control deterministic deformation sequence with rich programmability. Theoretical and numerical results reveal that tunable 1D to 3D large positive/zero/negative isotropic or anisotropic thermal expansions of single 1D to 3D multi-stable metamaterials can be achieved, respectively. This work suggests the rational designed metamaterials with multi-abnormal-index and the potential applications of multi-functional metamaterials.
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•1D to 3D multi-stable mechanical metamaterials are fabricated by assembly method with multi-materials.•Robust shape-reconfigurability and zero Poisson's ratio are achieved with large recoverable deformation.•Geometric and material gradients design are proposed to control deterministic deformation sequence.•Tunable 1D to 3D positive/zero/negative thermal expansions are achieved based on multi-stable mechanism.
This paper presents a four-level pulse amplitude modulation (PAM4) quarter-rate receiver that efficiently compensates for moderate channel loss in a robust manner through background adaptation of the ...receiver thresholds and equalization taps. The front-end utilizes an input single-stage continuous-time linear equalizer (CTLE) to boost the main cursor and relax the pre-cursor cancellation requirement, requiring only a 2-tap pre-cursor feed-forward equalizer (FFE) on the transmitter side. A 2-tap decision feedback equalizer (DFE) follows that includes one finite impulse response (FIR) tap and one infinite impulse response (IIR) tap to cancel first post-cursor and long-tail inter-symbol interference (ISI), respectively. In addition to the per-slice main three data samplers, a single error sampler is utilized for background threshold control and an edge-based sampler performs both phase-locked loop (PLL)-based clock and data recovery (CDR) phase detection and generates information for background DFE tap adaptation. Fabricated in general purpose (GP) 65-nm CMOS, the 56-Gb/s receiver achieves 4.63 mW/Gb/s and compensates for up to 20.8-dB loss at a bit error rate (BER) <; 10 -12 when operated with a 2-tap FFE transmitter.
•A numerical model for designing a free piston Stirling engine is proposed.•A prototype engine is designed and analyzed using proposed model.•The transient behaviors and performance of prototype ...engine are simulated.•Effects of loading and charged pressure on the performance are studied.
A free piston Stirling engine is a complex system that its transient behaviors of thermal properties and dynamic characteristics are coupled with each other. In order to assess the performance of the engine, the prediction of the aforementioned properties becomes unavoidable. In this study, a modified non-ideal adiabatic model and a dynamic model were solved simultaneously for determining the thermal properties of the working fluid and the dynamic behaviors of the displacer and piston. The energy equations of the working fluid in each working space were solved. The variations in the temperature, mass, and pressure of the working fluid in each working space in each time step were predicted. The displacements of the displacer and piston were also solved. The proposed model was used for predicting the phase angle, amplitude, frequency, power, and efficiency of the engine. A prototype engine was also designed on the basis of the proposed model. The performance of the prototype engine under different loading and charged pressure was studied. The results indicated that optimum charged pressure and loading values exist for achieving the maximum power output and efficiency. For the prototype engine, the maximum power reached 595 W at an operating frequency of 66.26 Hz and charged pressure of 50 bar.
Helicobacter pylori is a spiral-shaped gram-negative bacterium. Its infection is mainly transmitted via oral-oral and fecal-oral routes usually during early childhood. It can achieve persistent ...colonization by manipulating the host immune responses, which also causes mucosal damage and inflammation. H. pylori gastritis is an infectious disease and results in chronic gastritis of different severity in near all patients with infection. It may develop from acute/chronic inflammation, chronic atrophic gastritis, intestinal metaplasia, dysplasia, and intraepithelial neoplasia, eventually to gastric cancer. This review attempts to cover recent studies which provide important insights into how H. pylori causes chronic inflammation and what the characteristic is, which will immunologically explain H. pylori gastritis.
More than 30% of patients with diffuse large B-cell lymphoma (DLBCL) experience treatment failure after first-line therapy. Neutrophil extracellular traps (NETs), a pathogen-trapping structure in ...tumor microenvironment, can promote the transition of autoimmunity to lymphomagenesis. Here, we investigate whether NETs play a novel role in DLBCL progression and its underlying mechanism.
NETs in DLBCL tumor samples and plasma were detected by immunofluorescence and ELISA, respectively. The correlation between NETs and clinical features were analyzed. The effects of NETs on cellular proliferation and migration and mechanisms were explored, and the mechanism of NET formation was also studied by a series of
and
assays.
Higher levels of NETs in plasma and tumor tissues were associated with dismal outcome in patients with DLBCL. Furthermore, we identified NETs increased cell proliferation and migration
and tumor growth and lymph node dissemination
. Mechanistically, DLBCL-derived IL8 interacted with its receptor (CXCR2) on neutrophils, resulting in the formation of NETs via Src, p38, and ERK signaling. Newly formed NETs directly upregulated the Toll-like receptor 9 (TLR9) pathways in DLBCL and subsequently activated NFκB, STAT3, and p38 pathways to promote tumor progression. More importantly, disruption of NETs, blocking IL8-CXCR2 axis or inhibiting TLR9 could retard tumor progression in preclinical models.
Our data reveal a tumor-NETs aggressive interaction in DLBCL and indicate that NETs is a useful prognostic biomarker and targeting this novel cross-talk represents a new therapeutic opportunity in this challenging disease.
This letter presents a low-cost, single-layer, dual circularly polarized (CP) series-fed antenna based on the sequential rotation technique for millimeter-wave (MM-wave) applications. The series-fed ...working form endows the proposed antenna with more compact structure and lower ohmic, dielectric losses caused by the feeding network compared with parallel-fed antennas. The curved microstrip transmission lines are adopted as radiation elements; therefore, the whole antenna can be etched on a single-layer laminate using standard printed circuit board technology. These characteristics make the antenna a competitive candidate for MM-wave applications. To validate the proposed design, a dual-CP antenna operating at 30 GHz is fabricated. Based on the measurement, the proposed antenna has a 3 dB gain bandwidth of 1.97 GHz, the measured |S 21 | is lower than -20 dB, and the axial ratios are lower than 3 dB in the aforementioned frequencies.
In this paper, we consider the problem of asynchronous estimation in the presence of packet losses for the randomly sampling nonlinear system. Packet losses occur at the control input and at the ...measurement side. Firstly, the synchronization of the asynchronous sampling system is realized by weighting the state of the adjacent state update points. Secondly, the projection theorem is used to estimate the system state at the sampling time. Due to modeling errors and unmodeled dynamics, obtaining an accurate dynamic model is challenging. Therefore, observation inference based on interpolation techniques is proposed to solve the asynchronous estimation problem. Furthermore, the algorithm is extended to multi-sensor systems to obtain a distributed fusion estimator. Finally, simulation experiments are conducted to validate the effectiveness of the algorithm.
Chinese lesbian and bisexual women (LBW) often face difficulties and challenges on campus due to their multiple, socially-oppressed identities. These students have to navigate through uncharted ...environments to make meaning of their identities. In this qualitative study, by considering four environmental systems of student life, including the student club (microsystem), the university (mesosystem), families (exosystem), and society (macrosystem), we aim to explore what identity negotiation Chinese LBW students have in them and what their meaning-making capacity influence that identity negotiation. We find students experience identity security in the microsystem, identity differentiation-inclusion or inclusion in the mesosystem, and identity unpredictability-predictability or predictability in the exosystem and macrosystem. Moreover, they employ foundational, transitional (formulaic to foundational or symphonic), or symphonic meaning-making capacity to influence their identity negotiation. Suggestions are made for the university to create an inclusive climate accommodating students with different identities.
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