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To investigate the reasonable range of the inclination angle of arch ribs, a spatial finite element method was employed based on a concrete-filled steel tube (CFST) basket-handle through an arch bridge with a span of 360 m. A spatial finite element model was established using Midas/Civil software, which was verified with actual bridge data. The effects of different arch rib inclination angles were investigated under static loads. The structural natural frequencies, linear elastic stability coefficients, internal forces, and displacements were comprehensively considered to determine the reasonable range of the inclination angle. The results show that when the inclination angle ranges between 8° and 10°, the first, third, and sixth natural frequencies of the structure are increased. It effectively improves the lateral and torsional stiffness of the arch ribs while ensuring optimal out-of-plane stability of the arch ribs. Compared with the parallel arch, the stability is improved by 20.2%. The effects of angle variation on displacement and internal force of the arch ribs were not significant. Considering all indicators, the optimal range of the inclination angle for the arch ribs of 300-m-level highway CFST arch bridges is suggested to be 8~10°. [ABSTRACT FROM AUTHOR]

Background: Assisted reproductive technology (ART) is associated with an increased risk of adverse metabolic health in offspring, and these findings have been demonstrated in animal models without parental infertility issues. However, it is unclear what changes lead to abnormal metabolism. The activation of the renin-angiotensin system (RAS) has been related to various aspects of metabolic syndrome. Thus, we focused on the local RAS of the liver, which is the central organ for glucose and lipid metabolism in offspring conceived by in vitro fertilization (IVF), and studied the role of local liver RAS in metabolic diseases. Methods: Male C57BL/6 mouse offspring obtained by natural pregnancy and IVF were fed a standard chow diet or a high-fat diet (HFD) from 4 weeks of age through 16 weeks of age. We assessed glucose and lipid metabolism, hepatic histopathology, and the gene and protein expression of key RAS components. In addition, the blocker losartan was used from 4 weeks of age through 16 weeks of age to investigate the regulatory mechanisms of abnormal local RAS on metabolic activity in the IVF offspring liver. Results: The growth trajectories of IVF offspring body and liver weights were different from those of naturally pregnant offspring. Impaired glucose tolerance (IGT) and insulin resistance (IR) occurred in IVF-conceived male offspring. After continuous HFD feeding, male offspring in the IVF group underwent earlier and more severe IR. Furthermore, there was a trend of lipid accumulation in the livers of chow-fed IVF offspring. Hepatic steatosis was also more serious in the IVF offspring after HFD treatment. Type 1 receptor (AT1R), which is the primary receptor mediating the action of angiotensin (Ang) II, has been confirmed to be upregulated in IVF offspring livers. Losartan reduced or even eliminated most of the significant differences between the IVF and NC groups after HFD consumption. Conclusions: The upregulation of AT1R expression in the liver increased the activity of the local RAS, resulting in abnormal glucose and lipid metabolism and lipid accumulation in the liver, significantly increasing the risk of nonalcoholic fatty liver disease (NAFLD) in IVF offspring. [ABSTRACT FROM AUTHOR]

This paper presents a SOI piezoresistive pressure sensor with the crossbeam membrane. The roots of the crossbeam were widened, which solved the problem of the poor dynamic performance of small-range pressure sensors working at a high temperature of 200 °C. A theoretical model was established to optimize the proposed structure, which combined the finite element and the curve fitting. Using the theoretical model, the structural dimensions were optimized to obtain the optimal sensitivity. During optimization, the sensor nonlinearity was also taken into consideration. The sensor chip was fabricated by MEMS bulk-micromachining technology, and Ti/Pt/Au metal leads were prepared to improve the sensor ability of high-temperature resistance over a long time. The sensor chip was packaged and tested, and the experimental results show the sensor achieved an accuracy of 0.241% FS, nonlinearity of 0.180% FS, hysteresis of 0.086% FS and repeatability of 0.137% FS at the high temperature. Given the good reliability and performance at the high temperature, the proposed sensor provides a suitable alternative for the measurement of pressure at high temperatures. [ABSTRACT FROM AUTHOR]

Despite extensive research efforts in developing aqueous rechargeable zinc metal batteries (RZMBs) as high-energy-density alternatives to both lithium ion and lithium metal batteries, the commercial prospects for RZMBs are still obfuscated by fundamental scientific questions. In particular, the electrode–electrolyte interphase properties and behaviors are still intensely debated topics in this field. In this review, we provide a comprehensive and thorough overview of the solid electrolyte interphase (SEI) and cathode electrolyte interphase (CEI) in aqueous RZMBs, with an emphasis on the formation mechanisms and characteristics of the SEI and CEI. We then summarize state-of-the-art techniques for characterizing the SEI/CEI to reveal the intrinsic correlation between the functionalities of the interphases and the electrochemical performances. Finally, future directions are proposed, including studies on aqueous SEI/CEI evolution as a function of pH and temperature, as well as SEI/CEI studies for high-energy-density and long-lifetime RZMBs. [ABSTRACT FROM AUTHOR]

In perovskite solar cells (PSCs), the buried interface containing high concentrations of defects is critical for efficient charge extraction toward high‐performance device. Herein, porous organic cage (POC) is introduced between tin dioxide and perovskite to spontaneously reconstitute the buried interface. Through the chemical linkage formed by polydentate chelation of POC with SnO2 and perovskite, the buried interface achieves greatly reduced defect density and enhanced carrier extraction. More importantly, it is found that iodide ions in aged devices to migrate down to the electron transport layer and even invade the ITO electrode, changing the work function of ITO. This detrimental effect can be well resolved by POC since the host‐guest interaction of POC can effectively suppress the iodide ions trying to migrate downward. As a result, the PSC fabricated by POC‐restructured strategy yields a superior PCE of 24.13%. Moreover, the unencapsulated PSCs exhibit conspicuous improved long‐term stability and retain 93% of its initial efficiency after 5000 h in ambient condition. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is the most malignant and challenging type of astrocytoma and also notoriously acknowledged as the most common primary brain tumor globally. Currently, chemotherapy is the most master therapy for tumor and is essential in clinical treatment for GBM. Nevertheless, the characterization of chemotherapy resistance seriously hinders clinical chemotherapy treatment. Accordingly, there are imperious demands for the exploitation of novel chemosensitizer to promote the efficacy of chemotherapy. Our current study was conducted to probe into the potential impacts of microRNA (miR)-640 on the chemosensitivity in GBM and the associated underlying mechanism. Initially, TargetScan software was utilized to predict the targeted genes of miR-640, and the target relationship between miR-640 and Bcl-2-modifying factor (BMF) was validated by double luciferase report assay. Additionally, to explore the role of miR-640/BMF in U251 cells, miR-640 inhibitor/BMF-siRNA was used. U251 cells were processed with 100 μM temozolomide (TMZ) and detected with CCK-8 kit. Eventually, RT-qPCR and Western blotting were used for evaluating Bcl-2, Bax mRNA, and protein expression level. Flow cytometry analysis was performed to measure cellular apoptosis. Initially, the results indicated that BMF was the target gene of miR-640. MiR-640 negatively regulated BMF expression in GBM cells. Besides, the findings revealed that miR-640 inhibition significantly inhibited U251 cell proliferation, promoted cell apoptosis, and increased the sensitivity of GBM cells to TMZ by targeting BMF. Moreover, BMF overexpression significantly suppressed U251 cell proliferation, induced cell apoptosis, and increased the sensitivity of GBM cells to TMZ. Inhibition of miR-640 expression enhances chemosensitivity of human GBM cells to TMZ by targeting BMF. [ABSTRACT FROM AUTHOR]

Transformer insulating paperboard is an insulating material commonly used in the oil‐filled equipment in substations, which is usually immersed in the transformer oil. In this study, the effects of immersion time on the combustion characteristics of oil‐impregnated transformer insulating paperboard are studied using the thermogravimetric, UL94 vertical flammability, and cone calorimeter experiments. The experimental results show that the total oil content increases with increasing immersion time and reaches the saturation state in 240 h, with a saturation content of 14.7% ± 0.5%. However, the distribution of oil content inside the paperboard is uneven. At the saturation state, the surface oil content is 35.5%, being about 3 times of the core oil content. The results of UL94 vertical flammability experiments show that the flame spread rate increases with increasing immersion time and is controlled by the total oil content. In the cone calorimeter experiments, the time to ignition is significantly reduced compared to the clean paperboard. Unlike the flame spread rate, the ignition time is controlled by the surface oil content and barely varies with immersion time. The critical heat flux of oil‐impregnated transformer insulating paperboard is found as 3.9 kW/m2, being only 1/3 of clean paperboard. With increasing immersion time, the peak heat release rate increases, while the total heat release, fire growth index, and effective heat of combustion present linear correlations with the total oil content. The CO yield increases with increasing immersion time, and the released CO mainly comes from the combustion of transformer oil. [ABSTRACT FROM AUTHOR]

The connected and autonomous vehicle (CAV) is promised to ease congestion in the future with the rapid development of related technologies in recent years. To explore the characteristics of mixed-traffic flow and the dynamic transmission mechanism, this paper firstly detailed the car-following model of different vehicle types, establishing the fundamental diagram of the mixed-traffic flow through considering the different penetration rates and fleet size of CAV. Secondly, this paper constructed the lane-changing judgment mechanism based on the random utility theory. Finally, the paper proposed a lane-level dynamic cell transmission process, combined with a lane-changing strategy and cell transmission model. The effectiveness and feasibility of the model are verified using simulation analysis. This model makes a systematic, theoretical analysis from the perspective of the internal operation mechanism of traffic flow, and the lane-level traffic strategy provides a theoretical basis for balancing urban lane distribution and intelligent traffic management and control. [ABSTRACT FROM AUTHOR]

This paper presents a cryogenic 8-bit 32 MS/s successive approximation register (SAR) analog-to-digital converter (ADC) which operates down to 4.2 K. This work uses a modified liquid helium temperature (LHT) SMIC 0.18 μm CMOS technology to support the post-layout simulation. The proposed architecture adopts an offset-promoted dynamic comparator, waveform shaping circuit and true single-phase clock (TSPC) based sar logic circuit to achieve high realizing frequency and low power dissipation. At 1.8-V supply, 1.7 V input amplitude and 32 MS/s sampling frequency, the ADC achieves a power consumption of 2.4 mW and a signal-to-noise and distortion ratio (SNDR) of 47.7 dB, obtaining a figure of merit (FOM) of 378 fJ/conversion-step. The layout area of the ADC is about 0.253 mm 2 . [ABSTRACT FROM AUTHOR]

Background: NIPT is becoming increasingly important as its use becomes more widespread in China. More details are urgently needed on the correlation between maternal risk factors and fetal aneuploidy, and how these factors affect the accuracy of prenatal aneuploidy screening. Methods: Information on the pregnant women was collected, including maternal age, gestational age, specific medical history and results of prenatal aneuploidy screening. Additionally, the OR, validity and predictive value were also calculated. Results: A total of 12,186 analysable karyotype reports were collected with 372 (3.05%) fetal aneuploidies, including 161 (1.32%) T21, 81 (0.66%) T18, 41 (0.34%) T13 and 89 (0.73%) SCAs. The OR was highest for maternal age less than 20 years (6.65), followed by over 40 years (3.59) and 35–39 years (2.48). T13 (16.95) and T18 (9.40) were more frequent in the over-40 group (P < 0.01); T13 (3.62/5.76) and SCAs (2.49/3.95) in the 35–39 group (P < 0.01). Cases with a history of fetal malformation had the highest OR (35.94), followed by RSA (13.08): the former was more likely to have T13 (50.65) (P < 0.01) and the latter more likely to have T18 (20.50) (P < 0.01). The sensitivity of primary screening was 73.24% and the NPV was 98.23%. The TPR for NIPT was 100.00% and the respective PPVs for T21, T18, T13 and SCAs were 89.92, 69.77, 53.49 and 43.24%, respectively. The accuracy of NIPT increased with increasing gestational age (0.81). In contrast, the accuracy of NIPT decreased with maternal age (1.12) and IVF-ET history (4.15). Conclusions: ①Pregnant patients with maternal age below 20 years had higher risk of aneuploidy, especially in T13; ②A history of fetal malformations is more risky than RSA, with the former more likely to have T13 and the latter more likely to have T18; ③Primary screening essentially achieves the goal of identifying a normal karyotype, and NIPT can accurately screen for fetal aneuploidy; ④A number of maternal risk factors may influence the accuracy of NIPT diagnosis, including older age, premature testing, or a history of IVF-ET. In conclusion, this study provides a reliable theoretical basis for optimizing prenatal aneuploidy screening strategies and improving population quality. [ABSTRACT FROM AUTHOR]

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Maternal nutrition plays a critical role in energy metabolism of offspring. We aim to elucidate the effect of long-term intermittent fasting (IF) before pregnancy on health outcomes of offspring. Here we show long-term IF before pregnancy disrupts intestinal homeostasis of offspring with subsequent disorder of glucose and lipid metabolism. This occurs through the reduction in beneficial microbiota such as Lactobacillus_intestinalis. Our observations further support the concept that intestinal microbiota in offspring is vulnerable to maternal nutrition, and its homeostasis is critical for the integrity of intestinal barrier and metabolic homeostasis. Long-term intermediate fasting before pregnancy in mice disrupts intestinal homeostasis of offspring with subsequent glucose and lipid metabolism disorder, mediated by a reduction in beneficial microbiota such as Lactobacillus intestinalis. [ABSTRACT FROM AUTHOR]

We analyse the top-quark decay at the next-to-next-to-leading order (NNLO) in QCD by using the Principle of Maximum Conformality (PMC) which provides a systematic way to eliminate renormalization scheme and scale ambiguities in perturbative QCD predictions. The PMC renormalization scales of the coupling constant α s are determined by absorbing the non-conformal β terms that govern the behavior of the running coupling by using the Renormalization Group Equation (RGE). We obtain the PMC scale Q ⋆ = 15.5 GeV for the top-quark decay, which is an order of magnitude smaller than the conventional choice μ r = m t , reflecting the small virtuality of the QCD dynamics of the top-quark decay process. Moreover, due to the non-conformal β terms disappear in the pQCD series, there is no renormalon divergence and the NLO QCD correction term is greatly increased while the NNLO QCD correction term is suppressed compared to the conventional results obtained at μ r = m t . By further including the next-to-leading (NLO) electroweak corrections, the finite W boson width and the finite bottom quark mass, we obtain the top-quark total decay width Γ t tot = 1. 3112 - 0.0189 + 0.0190 GeV, where the error is the squared averages of the top-quark mass Δ m t = ± 0.7 GeV, the coupling constant Δ α s (M Z) = ± 0.0009 and the estimation of unknown higher-order terms using the PAA method with [N/M]=[1/1]. The PMC improved predictions for the top-quark decay are complementary to the previous PMC calculations for top-quark pair production and helpful for detailed studies of properties of the top-quark. [ABSTRACT FROM AUTHOR]

Purpose: We aimed to improve B0 magnetic field homogeneity and minimize the interference between RF coils and local B0 shimming coils with few channel numbers. Methods: To design and construct the prototype for B0 shimming of the rat brain, we first evaluated the interferences of single shimming loops on RF receiver loops. Then, B0 shimming of the whole rat brain was implemented using an optimization procedure. The positions and currents of the local shimming coils with channel numbers from 3 to 6 were optimized to improve shimming performance. Based on the simulation results, a 5‐channel local shimming coil, combined with a 3‐channel RF receiver coil, was constructed and evaluated by animal experiments. Results: There was marginal SNR loss within 5% after integrating the local shimming coil into the RF receiver coil. With respect to the Siemens standard shims up to second order, the B0 inhomogeneity in one whole rat brain was reduced from 39.6 Hz to 24.7 Hz by using the local shimming coil. A large portion of the EPI distortions was recovered after using the 5‐channel local shimming coil. The temporal SNR using the local shimming coil was higher than that using the Siemens standard shims up to second order, with an improvement of more than 24%. Conclusions: The local shimming coil can improve B0 magnetic field homogeneity despite minor effects on the RF coil and can benefit a variety of applications that are sensitive to B0 inhomogeneity. Nevertheless, EPI for rat brain is still very challenging. [ABSTRACT FROM AUTHOR]