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In order to realize the precise phase correction of high order modulation in M-APSK modem, the Q-power non-data aided phase detection method recommended by DVB-S2 standard for 16APSK and 32APSK was extended to 64APSK, 128APSK and 256APSK.An improved algorithm was proposed to solve the problem of unstable loop operation when the proportion of constellation points used for phase detection in high-order modulation was low.By using threshold judgment on the amplitude of the received symbol after power normalization, phase detection was performed only when the amplitude was higher than the threshold, and the filter state and phase compensation value were not changed when the amplitude was lower than the threshold, so as to improve the phase detection effectiveness and reliability of constellation points and reduce the lock threshold.Aiming at the problem that the symbol rate of high-speed data transmission was very high but the working clock frequency of the processor was relatively low, a parallel carrier synchronization method for M-APSK was proposed, which could meet the needs of the receiver’s working clock.Compared with the traditional constant coding and modulation (CCM) carrier synchronization loop, the parallel method could also be applied to the frequency tracking of variable coding and modulation (VCM) system.

Abstract Two-dimensional (2D) topological insulators, a type of the extraordinary quantum electronic states, have attracted considerable interest due to their unique electronic properties and promising potential applications. Recently, the successful fabrication of 2D Te monolayers (i.e. tellurene) in experiments (Zhu et al., Phys Rev Lett 119:106101, 2017) has promoted researches on the group-VI monolayer materials. With first-principles calculations and tight-binding (TB) method, we investigate the structures and electronic states of 2D polonium (poloniumene), in which Po is a congener of Te. The poloniumene is found to have the tendency of forming a three-atomic-layer 1 T-MoS2-like structure (called trigonal poloniumene), namely, the central-layer Po atoms behave metal-like, while the two-outer-layer Po atoms are semiconductor-like. This unique multivalent behavior of the Po atoms is conducive to the structural stability of the monolayer, which is found to be an intrinsic quantum spin Hall insulator with a large band gap. The nontrivial topology originates from the $$p_{x,y} - p_{z}$$ p x , y - p z band inversion, which can be understood based on a built TB model. The poloniumene with different congener elements doped is also explored. Our results provide a thorough understanding of structures and electronic states of 2D polonium-related materials.

As a novel topological state, a higher-order topological insulator has attracted enormous interest, which in d spatial dimensions has gapless boundary states at (d-n) dimensions (integer n is larger than 1). Until now, merely few two-dimensional (2D) materials have been identified as higher-order topological insulators and their experimental confirmations are still absent. Here we propose a universal strategy of antidot engineering to realize second-order topological insulators (SOTIs) in 2D Dirac materials. Based on symmetry analysis, tight-binding model, and first-principles calculations, we demonstrate SOTIs in antidot-decorated Xene (X=C, Si,and Ge) by displaying its finite bulk quadrupole moment, weak topological edge states, and in-gap topological corner states. An inherent connection is established for the existing various mechanisms of the SOTIs, including quadrupole polarization, filling anomaly, and generalized Su-Schrieffer-Heeger model on a Kekulé lattice. The robustness of topological corner states of the SOTIs against edge perturbations and bulk disorders is explicitly demonstrated, rendering our strategy appealing to experimental realization of topological corner states.

Graphene is a kind of two-dimensional atomic crystal with one atomic layer, which is the basic structure unit of other dimensions of graphite materials, such as zero dimensional fullerenes, one-dimensional carbon nanotubes and three-dimensional graphite. Graphene has a lot of unique electronic and mechanical properties, which have attracted high attention of many scientists in the field of chemistry, materials and other fields. Raman spectroscopy as a sensitive and convenient characterization method, has played a very important role in the study of graphene. Raman spectroscopy is an integral part of graphene research. The application of Raman spectroscopy in graphene characterization in recent years is reviewed in this paper. The characteristic peak of monolayer graphene was first intnduced. Then, through the analysis of the changes of D peak, G peak and 2D peak intensity, position and half peak width of Raman spectra, the number of graphene layers can be quickly and accurately characterized, as well as, the stacking orders, edge chirality and doping degree of graphene were defined. At the same time, the effects of substrate, doping, temperature and laser power on the intensity, position and half width of D peak, G peak and 2D peak of Raman spectra in the process of preparing graphene were also systematically analyzed.

The utilization of Global Navigation Satellite System (GNSS) is becoming an attractive navigation approach for geostationary orbit (GEO) satellites. A high-sensitivity receiver compatible with Global Position System (GPS) developed by the United States and BeiDou Navigation Satellite System (BDS) developed by China has been used in a GEO satellite named TJS-5 to demonstrate feasibility of real-time navigation. According to inflight data, the GNSS signal characteristics including availability, position dilution of precision (PDOP), carrier-to-noise ratio (C/N0), observations quantity and accuracy are analyzed. The mean number of GPS and GPS + BDS satellites tracked are 7.4 and 11.7 and the mean PDOP of GPS and GPS + BDS are 10.24 and 3.91, respectively. The use of BDS significantly increases the number of available navigation satellites and improves the PDOP. The number of observations with respect to C/N0 is illustrated in detail. The standard deviation of the pseudorange noises are less than 4 m, and the corresponding carrier phase noises are mostly less than 8 mm. We present the navigation performance using only GPS observations and GPS + BDS observations combination at different weights through comparisons with the precision reference orbits. When GPS combined with BDS observations, the root mean square (RMS) of the single-epoch least square position accuracy can improve from 32.1 m to 16.5 m and the corresponding velocity accuracy can improve from 0.238 m/s to 0.165 m/s. The RMS of real-time orbit determination position accuracy is 5.55 m and the corresponding velocity accuracy is 0.697 mm/s when using GPS and BDS combinations. Especially, the position accuracy in x-axis direction reduced from 7.24 m to 4.09 m when combined GPS with BDS observations.

Respiration rate is an essential indicator of vital signs, which can demonstrate the physiological condition of the human body and provide clues to some diseases. Commercial Wi-Fi devices can provide a non-invasive, cost-effective and long-term respiration rate-monitoring scheme for home scenarios. However, previous studies show that the breathing depth and location may affect the detectability of respiratory signals. In this study, we leverage the variation of the Doppler spectral energy extracted from the channel state information (CSI) collected by Wi-Fi devices to track the chest displacement induced by respiration. First, the random phase is eliminated by phase-fitting method to obtain the complex CSI containing the Doppler shift. Then, the multipath decomposition of CSI is carried out to obtain the channel impulse response, which eliminates the interference phase of the time delay and retains the Doppler shift. The dynamic path units are also separate from the multipath, which overcomes the indoor multipath effect. Finally, we conduct a time–frequency analysis to dynamic units to accumulate Doppler spectral energy. Based on these ideas, we design a complete respiration rate-monitoring system to obtain the respiration rate by using the consistency between the Doppler energy change period and the respiratory cycle. We evaluate our system through extensive experiments in several typical home environments filled with multipath. Experimental results show that the errors of the three scenarios are approximate, the maximum error is less than 0.7 bpm, and the average errors are approximately 0.15 bpm. This result indicates that our scheme can achieve high precision respiration monitoring and has good anti-multipath ability compared with existing methods.

The thermal deformation microstructure of continuous extrusion copper bus bar was observed and analyzed in the temperature range from 200°C to 700°C and at strain rate from 0.01s-1 to 10.0s-1 and at deformation amount from30% to 90% on Gleeble1500 test machine. The experiment results show that the higher the temperature, the lower the strain rate, the more dynamic recrystallization occurred. At the same strain rate, the copper bus bar changes from raw material of as-cast organization to recrystallization grain gradually as the deformation temperature and deformation degree increase, and the recrystallization grain size grows older with the rise of temperature. At the same deformation temperature, the temperature of recrystallization nucleation decreases while the strain rate increases. At low strain rate (0.01~1.0s-1), the dynamic recrystallization occurred at 500°C. While at high strain rate (10.0s-1), the recrystallization nucleation is advanced and it is already completed at 500°C. The Z parameters can be used to express the effect of deformation temperature and strain rate on the average grain size D, and the prediction model of the thermal deformation microstructure is obtained as follows: lnD=4.822-0.018lnZ

Objective of this study was to investigate the effect of neutrophil-to-lymphocyte ratio (NLR) on the survival of cirrhotic patients with esophagogastric variceal bleeding (EGVB) treated with transjugular intrahepatic portosystemic shunt (TIPS). Methods: A total of 293 patients treated with TIPS were included. The receiver operator characteristic curve (ROC) was used to calculate the optimal cut-off values of parameters such as NLR. The Kaplan-Meier curve and Cox proportional risk model were used to evaluate the effects of NLR and other variables on 2-year all-cause mortality. Results: The area under the ROC for NLR was 0.634, with an optimal cutoff value of 4.9. Two-year mortality rates for patients with high (≥ 4.9) and low (< 4.9) NLR were 22.1% and 9.3%, respectively (Log rank test: P = 0.002). After correcting for confounders, multivariate analysis demonstrated that NLR ≥ 4.9 (HR = 2.741, 95% CI 1.467– 5.121, P = 0.002), age ≥ 63 (HR = 3.403, 95% CI 1.835– 6.310, P < 0.001), and gender (male) (HR = 2.842, 95% CI 1.366– 5.912, P = 0.001) were independent risk factors for the mortality outcome. Considering the stratification of early and selective TIPS treatment, high NLR still significantly increased the risk of mortality for patients (Log rank test: P = 0.007, HR = 2.317, 95% CI 1.232– 4.356). Conclusion: NLR can help to predict survival in EGVB patients after TIPS, and the type of TIPS should also be considered in practical applications. [ABSTRACT FROM AUTHOR]

In order to study the horizontal well multi-segment multi-cluster fracture extension in the deep coal reservoir where the cleat fissures are developed, a multi-segment multi-cluster fracture extension model is created based on the extended finite element and taking into account the inter-seam interference and the induced stress field. With the secondary development of pre-processing in Python language, a large number of approximately orthogonal cleat fissures were added into the model. The effects of cluster spacing, fracturing sequence and segment spacing on multi-fracture extension were analyzed, and the advantages and disadvantages of fracturing effect were verified by querying the number of fracture-communicating cutting groups. The simulation results show that when the cluster spacing is 20 m and the segment spacing is 40-45 m, the number of fracture communication cutting groups is relatively high, and the fracture length is optimal due to the small influence of inter-seam interference and induced stress field; at the aspect of the influence of different fracturing sequences on the extension of multi-fractures, the fracturing effects are ranked from excellent to poor: sequential fracturing > alternating fracturing > synchronous fracturing. The results of modeling and field application are in good agreement, with 96.5% for the second fracturing section and 93.4% for the third fracturing section.

Abstract Background Normal tissue and immune organ protection are critical parts of the tumor radiation therapy process. Radiation-induced immune organ damage (RIOD) causes several side reactions by increasing oxidative stress and inflammatory responses, resulting in unsatisfactory curability in tumor radiation therapy. The aim of this study was to develop a novel and efficient anti irradiation nanoparticle and explore its mechanism of protecting splenic tissue from radiation in mice. Methods Nanoparticles of triphenylphosphine cation NIT radicals (NPs-TPP-NIT) were prepared and used to protect the spleens of mice irradiated with X-rays. Splenic tissue histopathology and hematological parameters were investigated to evaluate the protective effect of NPs-TPP-NIT against X-ray radiation. Proteomics was used to identify differentially expressed proteins related to inflammatory factor regulation. In addition, in vitro and in vivo experiments were performed to assess the impact of NPs-TPP-NIT on radiation therapy. Results NPs-TPP-NIT increased superoxide dismutase, catalase, and glutathione peroxidase activity and decreased malondialdehyde levels and reactive oxygen species generation in the spleens of mice after exposure to 6.0 Gy X-ray radiation. Moreover, NPs-TPP-NIT inhibited cell apoptosis, blocked the activation of cleaved cysteine aspartic acid–specific protease/proteinase, upregulated the expression of Bcl-2, and downregulated that of Bax. We confirmed that NPs-TPP-NIT prevented the IKK/IκB/NF-κB activation induced by ionizing radiation, thereby alleviating radiation-induced splenic inflammatory damage. In addition, when used during radiotherapy for tumors in mice, NPs-TPP-NIT exhibited no significant toxicity and conferred no significant tumor protective effects. Conclusions NPs-TPP-NIT prevented activation of IKK/IκB/NF-κB signaling, reduced secretion of pro-inflammatory factors, and promoted production of anti-inflammatory factors in the spleen, which exhibited radiation-induced damage repair capability without diminishing the therapeutic effect of radiation therapy. It suggests that NPs-TPP-NIT serve as a potential radioprotective drug to shelter immune organs from radiation-induced damage.

Abstract Background Growing evidence shows that ultra-processed food consumption is associated with the risk of cancer. However, prospective evidence is limited on renal cell carcinoma (RCC) incidence and mortality. In this study, we aimed to examine the association of ultra-processed food consumption and RCC incidence and mortality in a large cohort of US adults. Methods A population-based cohort of 101,688 participants were included from the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. Ultra-processed food items were confirmed by using the NOVA food classification system. The consumption of ultra-processed food was expressed as a percentage of total food intake (g/day). Prospective associations were calculated using Cox regression. Restricted cubic spline regression was used to assess nonlinearity. Subgroup analyses were performed to investigate the potential effect modifiers on the incidence and mortality of RCC. Results A total of 410 participants developed RCC during a total of 899,731 person-years of follow-up (median 9.41 years) and 230 RCC deaths during 1,533,930 person-years of follow-up (median 16.85 years). In the fully adjusted model, participants in the highest compared with the lowest quintiles of ultra-processed food consumption had a higher risk of RCC (HR quartile 4 vs 1:1.42; 95% CI: 1.06–1.91; P trend = 0.004) and mortality (HR quartile 4 vs. quartile 1: 1.64; 95% CI: 1.10–2.43; P trend = 0.027). Linear dose–response associations with RCC incidence and mortality were observed for ultra-processed food consumption (all P nonlinearity > 0.05). The reliability of these results was supported by sensitivity and subgroup analyses. Conclusion In conclusion, higher consumption of ultra-processed food is associated with an increased risk of RCC incidence and mortality. Limiting ultra-processed food consumption might be a primary prevention method of RCC.

Abstract Infant cerebral blood flow (CBF) delivers nutrients and oxygen to fulfill brain energy consumption requirements for the fastest period of postnatal brain development across the lifespan. However, organizing principle of whole-brain CBF dynamics during infancy remains obscure. Leveraging a unique cohort of 100+ infants with high-resolution arterial spin labeled MRI, we find the emergence of the cortical hierarchy revealed by the highest-resolution infant CBF maps available to date. Infant CBF across cortical regions increases in a biphasic pattern featured by initial rapid and subsequently slower rate, and break-point ages increasing along the limbic-sensorimotor-association cortical gradient. Increases in CBF in sensorimotor cortices are associated with enhanced language and motor skills, and frontoparietal association cortices with cognitive skills. The study discovers emergence of the hierarchical limbic-sensorimotor-association cortical gradient in infancy and offers standardized reference of infant brain CBF and insight into the physiological basis of cortical specialization and real-world infant developmental functioning.

This study investigates the interactions between virtual cities in electronic (video) games and real urban environments, highlighting a significant gap in the literature regarding the influence of real cities on virtual counterparts and vice versa. Drawing on classical urban theories, it sets two primary objectives: to systematically review how real cities are represented in games and to explore the impacts of virtual cities on real urban areas. Through typological analysis, it identifies two pathways – form and function – through which real cities manifest in games, using specific cases like Cities: Skylines to illustrate these pathways. The principle for virtual city design is also outlined, with an emphasis on the “selection” and “subtraction” of real urban elements in designing processes. Additionally, it discusses how virtual cities impact urban tourism, fostering phenomena like anime pilgrimages, and urban planning, and enhancing public engagement in planning processes. Finally, this research contributes to some newly emerging theories such as Digital Twins by elucidating the interactive relationship between physical and virtual urban spaces.

Abstract Background The glucose transporter 2 (GLUT2) is constitutively expressed in pancreatic beta cells and hepatocytes of mice. It is the most important receptor in glucose-stimulated insulin release and hepatic glucose transport. The Sema4D is a signalin receptor on cell membranes. The correlation between Sema4D and GLUT2 has not been reported previously. We investigated whether knockdown of Sema4D could exert a hypoglycemic effect based on the increased GLUT2 expression in Sema4D -/- mice hepatocytes. Methods The glucose tolerance test and insulin tolerance test in sema4D -/- and sema4D +/+ mice were compared before and after streptozotocin (STZ) injection; the expression of GLUT2 content on the membrane surface of both groups was verified by Western blot. Then, the levels of insulin and C-peptide in the serum of the two groups of mice after STZ injection were measured by ELISA; the differentially expressed mRNAs in the liver of the two groups of mice were analyzed by transcriptomic analysis; then the differences in the expression of GLUT2, glycogen, insulin and glucagon in the two groups of mice were compared by tissue section staining. Finally, metabolomics analysis was performed to analyze the metabolites differentially expressed in the two groups of mice. Key findings First, Sema4D -/- male mice exhibited significantly greater glucose tolerance than wild-type mice in a hyperglycemic environment. Secondly, Sema4D -/- mice had more retained GLUT2 in liver membranes after STZ injection according to an immunofluorescence assay. After STZ injection, Sema4D -/- male mice did not exhibit fasting hyperinsulinemia like wild-type mice. Finally, analysis of metabolomic and immunohistochemical data also revealed that Sema4D -/- mice produce hypoglycemic effects by enhancing the pentose phosphate pathway, but not glycogen synthesis. Conclusions Thus, Sema4D may play an important role in the regulation of glucose homeostasis by affecting GLUT2 synthesis.

This paper focuses on the effect of a 0.1 T static horizontal magnetic field on the corrosion of X70 pipeline steel in 0–0.05 mol/L sodium bicarbonate solutions. The weight loss data indicate that the magnetic field reduces the average corrosion rate during immersion within 48 h in all the test solutions. The magnetic field tends to increase the average corrosion rates for the immersion time of 72 h and 96 h. The magnetic field increases the proportion of magnetite in corrosion products formed on the specimen of immersion in 0.05 mol/L sodium bicarbonate solution for 168 h. The open-circuit potentials (OCP) are in the active zone of the E-pH diagram within 48 h immersion with 0 T and 0.1 T magnetic field. A 0.1 T magnetic field delays the process for the electrode to enter the passive zone of the E-pH diagram. The linear polarisation resistance (LPR) data shows that the resistance of the active zone with 0.1 T magnetic field is larger than that with 0 T. The electrochemical impedance results also indicate that the electrode is in an active state when the potential is below −700 mVSCE and in a passive state when the potential is above −200 mVSCE.

Torque density, torque range and response time are the problems to be solved urgently in the field of magnetorheological (MR) transmission. To improve the torque, the most frequently used techniques are increasing the effective area and magnetic field strength of MR fluids, such as multiple gaps and multiple coils designs. This paper proposed a multi-drum MR brake with side-set dual-coil. First, a structure description of the multi-drum MR brake is presented. The torque and torque density models are established. Then, an approximate optimization is conducted to obtain the optimal values for main dimensional parameters. Finally, a brake prototype is manufactured and the performance is validated. Experimental results indicate that the maximum torque is 6.8 N m, and the torque density is 37.866 kN m−2 when the two magnetic fields are superimposed together. Different torque capability and torque density can be gained by controlling the magnitude and direction of input current of the two coils. The results indicate that the torque capacity, torque density and torque range can be improved by the two coils. Furthermore, it can be concluded that the coil current has little effect on the transient time while the rising time is affected by the rotational speed.