Design and Evaluation of Digital Baseband Converter Sub-channel Delay Compensation Method on Bandwidth Synthesis

The effect of sub-channel delay on bandwidth synthesis is investigated to eliminate the “phase step” phenomenon in bandwidth synthesis during the test of CDBE (Chinese Digital Backend). Through formula derivation, we realize that sub-channel delay may cause phase discontinuity between different sub-channels. Theoretical analysis shows that sub-channel delay can induce bandwidth synthesis error in group delay measurement of the linear system. Furthermore, in the differential delay measurement between two stations, bandwidth synthesis error may occur when the LO (Local Oscillator) frequency differences of corresponding sub-channels are not identical. Error-free conditions are discussed under different applications. The phase errors among different sub-channels can be removed manually. However, the most effective way is the compensation of sub-channel delay. A sub-channel delay calculation method based on Modelsim is proposed. The compensation method is detailed. Simulation and field experiments are presented to verify our approach

Regulatory role of the programmed cell death 1 signaling pathway in sepsis induced immunosuppression

Sepsis is a multiple organ dysfunction syndrome caused by the host’s immune response to infection, with extremely high incidence and mortality. Immunosuppression is an essential pathophysiological alteration that influences the clinical treatment and prognosis of sepsis. Recent studies have suggested that the programmed cell death 1 signaling pathway is involved in the formation of immunosuppression in sepsis. In this review, we systematically present the mechanisms of immune dysregulation in sepsis and elucidate the expression and regulatory effects of the programmed cell death 1 signaling pathway on immune cells associated with sepsis. We then specify current research developments and prospects for the application of the programmed cell death 1 signaling pathway in immunomodulatory therapy for sepsis. Several open questions and future research are discussed at the end

Types and Formation Mechanism of Typical Submarine Geological Hazards of Coastal Islands in China

1774-1782Single beam, side-scan sonar, sub-bottom profiler and other survey equipments are adopted for investigation of submarine geological hazards in 15 coastal islands of China, namely, Zhangzi Is., Changxing Is., Caofeidian Is., Lingshan Is., Tuoji Is., Beichangshan Is., Chongming Is., Liuheng Is., Waidiaoshan Is., Xiushan Is., Zhujiajian Is., Jintang Is., Dongshan Is., Donghai Is. and Weizhou Is.. Data analysis and researches show that typical submarine geological hazards of coastal islands in china mainly cover 10 types: submarine landslide, submarine slope, seabed erosion, tidal ridges, moving sandwaves, shallow gas, wedge-shaped deposits, buried oblique layer, seabed siltation and coral reef degradation, and can be classified into gravity - hydrodynamic force cause, hydrodynamic force cause, pneumatic force cause, biological activity cause and human activity cause, among which hydrodynamic force cause accounts for the largest proportion and seabed erosion is the most developed, with the proportion of geological hazard attributed to human activity increasing rapidly

Maritime cognitive workload assessment

The human factor plays the key role for safety in many industrial and civil every-day operations in our technologized world. Human failure is more likely to cause accidents than technical failure, e.g. in the challenging job of tugboat captains. Here, cognitive workload is crucial, as its excess is a main cause of dangerous situations and accidents while being highly participant and situation dependent. However, knowing the captain’s level of workload can help to improve man-machine interaction. The main contributions of this paper is a successful workload indication and a transfer of cognitive workload knowledge from laboratory to realistic settings

The microstructure characteristic of cohesive soil in inner shelf of the East China Sea and its engineering implication

389-396In this paper, the microstructure images and parameters of the cohesive soil were obtained via scanning electron microscope testing technology and computer image processing technology. The physical-mechanical indexes of cohesive soil was obtained through geotechnical testing. The macro physical-mechanical indexes and microstructure parameters of cohesive soil in the inner shelf of the East China Sea were analysed by the regression analysis method; and the multiple regression equations between water content, liquid limit, compressibility coefficient, vane shear strength, micro-penetration resistance, medium diameter and the microstructure parameters were established. The results show that cohesive soils in the inner shelf of the East China Sea have three types of microstructure: Granular link-bond structure, flocculent link-bond structure and clay particle matrix structure. The physical indexes of cohesive soil mainly related to the microstructure parameters characterizing the size and number of pores, while the mechanical indexes, besides the size and number, also affected by the geometry of pores. Usually, the rounder the pore is and the more complicated the profile curve of pore is, the higher is the strength of cohesive soil. The results can provide theoretical reference for in-depth understanding the engineering properties of cohesive soil in the inner shelf of the East China Sea

Blocking senescence and tolerogenic function of dendritic cells induced by γδ Treg cells enhances tumor-specific immunity for cancer immunotherapy

BACKGROUND: Regulatory T (Treg) cells are a key component in maintaining the suppressive tumor microenvironment and immune suppression in different types of cancers. A precise understanding of the molecular mechanisms used by Treg cells for immune suppression is critical for the development of effective strategies for cancer immunotherapy. METHODS: Senescence development and tolerogenic functions of dendritic cells (DCs) induced by breast cancer tumor-derived γδ Treg cells were fully characterized using real-time PCR, flow cytometry, western blot, and functional assays. Loss-of-function strategies with pharmacological inhibitor and/or neutralizing antibody were used to identify the potential molecule(s) and pathway(s) involved in DC senescence and dysfunction induced by Treg cells. Impaired tumor antigen HER2-specific recognition and immune response of senescent DCs induced by γδ Treg cells were explored in vitro and in vivo in humanized mouse models. In addition, the DC-based HER2 tumor vaccine immunotherapy in breast cancer models was performed to explore the enhanced antitumor immunity via prevention of DC senescence through blockages of STAT3 and programmed death-ligand 1 (PD-L1) signaling. RESULTS: We showed that tumor-derived γδ Treg cells promote the development of senescence in DCs with tolerogenic functions in breast cancer. Senescent DCs induced by γδ Treg cells suppress Th1 and Th17 cell differentiation but promote the development of Treg cells. In addition, we demonstrated that PD-L1 and STAT3 signaling pathways are critical and involved in senescence induction in DCs mediated by tumor-derived γδ Treg cells. Importantly, our complementary in vivo studies further demonstrated that blockages of PD-L1 and/or STAT3 signaling can prevent γδ Treg-induced senescence and reverse tolerogenic functions in DCs, resulting in enhanced HER2 tumor-specific immune responses and immunotherapy efficacy in human breast cancer models. CONCLUSIONS: These studies not only dissect the suppressive mechanism mediated by tumor-derived γδ Treg cells on DCs in the tumor microenvironment but also provide novel strategies to prevent senescence and dysfunction in DCs and enhance antitumor efficacy mediated by tumor-specific T cells for cancer immunotherapy