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Abstract Objective To analyze the value of combining computed tomography (CT) with serum tumor markers in the differential diagnosis of benign and malignant solitary pulmonary nodules (SPNs). Methods The case data of 267 patients diagnosed with SPNs in the First Affiliated Hospital of Zhengzhou University from March 2020 to January 2023 were retrospectively analyzed. All individuals diagnosed with coronavirus disease 2019 (COVID-19) were confirmed via respiratory specimen viral nucleic acid testing. The included cases underwent CT, serum tumor marker testing and pathological examination. The diagnostic efficacy and clinical significance of CT, serum tumor marker testing and a combined test in identifying benign and malignant SPNs were analyzed using pathological histological findings as the gold standard. Finally, a nomogram mathematical model was established to predict the malignant probability of SPNs. Results Of the 267 patients with SPNs, 91 patients were not afflicted with COVID-19, 36 exhibited malignant characteristics, whereas 55 demonstrated benign features. Conversely, within the cohort of 176 COVID-19 patients presenting with SPNs, 62 were identified as having malignant SPNs, and the remaining 114 were diagnosed with benign SPNs. CT scans revealed statistically significant differences between the benign and malignant SPNs groups in terms of CT values (P

Two-dimensional (2D) MoTe2 shows great potential for future semiconductor devices, but the lab-to-fab transition is still in its preliminary stage due to the constraints in the crystal growth level. Currently, the chemical vapor deposition growth of 2D MoTe2 primarily relies on the tellurization process of Mo-source precursor (MSP). However, the target product 2H-MoTe2 from Mo precursor suffers from long growth time and suboptimal crystal quality, and MoOx precursor confronts the dilemma of unclear growth mechanism and inconsistent growth products. Here, we developed magnetron-sputtered MoO3 film for fast and high-mobility 2H-MoTe2 growth. The solid-to-solid phase transition growth mechanism of 2D MoTe2 from Mo and MoOx precursor was first experimentally unified, and the effect mechanism of MSPs on 2D MoTe2 growth was systematically elucidated. Compared with Mo and MoO2, the MoO3 precursor has the least Mo-unit lattice deformation and exhibits the optimal crystal quality of growth products. Meanwhile, the lowest Gibbs free energy change of the chemical reaction results in an impressive 2H-MoTe2 growth rate of 8.07 μm/min. The constructed 2H-MoTe2 field-effect transistor array from MoO3 precursor showcases record-high hole mobility of 85 cm2·V-1·s-1, competitive on-off ratio of 3×104, and outstanding uniformity. This scalable method not only offers efficiency but also aligns with industry standards, making it a promising guideline for diverse 2D material preparation towards real-world applications.

BackgroundTo quantify the changes in dynamic visual acuity (DVA) and explain the hidden reasons after acute exposure to hypobaric hypoxia status.MethodsThe study group comprised 18 healthy male and 15 healthy female participants aged 20–24 years old. DVA was measured with the self-developed software of Meidixin (Tianjin) Co., Ltd. Measurements were taken at eight altitudes. Data analysis was performed using the Kolmogorov–Smirnov test, paired sample T-test, and two-way repeated measures analysis of variance (ANOVA) for repeated measurements.ResultsAt constant altitude, DVA showed an overall decreasing trend with increasing angular velocity and a fluctuating decrease at the vast majority of altitudes. At constant angular velocities, DVA gradually increased with altitude, with the most pronounced increase in DVA at altitude 5, and thereafter a gradual decrease in DVA as altitude increased. Finally, as altitude decreased, DVA increased again and reached a higher level at the end of the experiment, which was superior to the DVA in the initial state.ConclusionUnder a hypobaric hypoxic environment at high altitude, DVA was affected by the angular velocity and the degree of hypoxia, manifesting as an increase or decrease in DVA, which affects the pilot's observation of the display and control interfaces during the driving process, acquisition of information, and decision-making ability, which in turn may potentially jeopardize the safety of the flight.

Abstract This work proposes a storage element (SE) design for in‐memory computing (IMC). Using the proposed SE design, an IMC array has been constructed to enable in‐situ updates of stored weights. Compared with some existing related works which employ 2n bit cells for storing an n‐bit value, the proposed structure in this work exhibits a O(n) complexity of area overhead, which means that only n bit cells are needed to store n‐bit values, offering a significant improvement in silicon area usage. Compared to the purely digitally‐controlled weight update schemes, the approach proposed in this work demonstrates an approximate 1.47× increase in power consumption. Furthermore, it exhibits superior robustness compared to existing work. Additionally, the proposed SE design can achieve the necessary shift functionality in the cutting‐edge floating‐point (FP)‐IMC architecture through simple control mechanisms.

During the diamond wire saw cutting process of sapphire crystals, warpage is one of the key parameters for evaluating wafer quality. Based on the thermoelasticity theory and diamond wire saw cutting theory, a finite element model for thermal analysis of diamond wire saw cutting sapphire crystals was established in this paper. The variation laws and internal connections of the temperature field and thermal deformation displacement field of the wafer during the sawing process were analyzed. A calculation and analysis model for the warpage of sapphire crystal wafer cut by wire saw was established based on the node thermal deformation displacement field of the wafer, and the rationality of the simulation results was verified through sawing experiments. This simulation calculation model constructs the mapping relationship between the process parameters of diamond wire sawing and the sapphire wafer warpage during sawing. The influence of wafer thickness, diamond wire speed, feed rate, diamond wire diameter, and tension on the warpage of the wafer was studied using the simulation model. The results indicate that the highest temperature occurs in the sawing area during cutting. The wafer thickness decreases and the warpage increases. The wafer warpage decreases with the increase of the diamond wire tension and diameter, and increases with the increase of diamond wire speed and feed rate. The research results provide a reference for understanding the variation of wafer warpage during sawing and optimizing sawing process parameters.

Electric field-assisted sintering technology (FAST) was used to join SiC ceramic by using a CoFeCrNiCu high-entropy alloy filler. A thin Ti film was deposited on SiC surface by physical vapor deposition to reduce the residual thermal stress in the joint. The microstructure, bending strength, and bonding mechanism were systematically investigated. It was found that a discontinuous TiC layer could be formed at the interface and the interfacial reaction products changed with different brazing temperatures. A joint with a bending strength of 72 MPa was achieved at 1200 °C, which is 73% higher than that of the SiC brazed without Ti coating. This work provides a new insight in the interfacial design of ceramic brazing with high mechanical properties.

Abstract Liquid unidirectional transport exhibits critical applications from water harvesting to microfluidics. Despite extensive progress, implementation of liquid unidirectional transport that is not subjected to the liquid surface tension and injecting velocity also remains a great challenge. Here, a tilted‐sector arrayed tube for excellent liquid unidirectional transport is proposed that applies to a vast width domain of liquid surface tension and injecting velocity. In addition, the transport direction is abnormally against the tilted direction of structure, in stark contrast to the traditional understanding that is along tilted direction. This excellent and unique liquid unidirectional transport is caused by synergistic effects of tilted sectors and tube structures, which induce a unique 3D liquid propagation mode as well as a large Laplace pressure asymmetry between the front and rear sides of the liquid. Moreover, the antigravity climbing, circuit isolating, and chemical reaction controlling can be achieved based on the excellent liquid unidirectional transport. It is envisioned that the design can be extensively applied in microfluidics, lab‐on‐a‐chip devices, and biochemistry microreactors.

A new method is proposed to increase the resonant frequency of a Capacitive Micromachined Ultrasonic Transducer (CMUT) device while keeping the radii unchanged for devices fabricated by sacrificial release (SR) method. The resonant frequency of a CMUT cell is determined by the properties of the membrane such as the Young’s modulus, membrane dimensions and effective membrane mass. Effective Young’s modulus is used to calculate the resonant frequency of CMUT fabricated by SR method. The supporting post structure will affect the boundary conditions at the edge of the CMUT membrane and in turn affect the deflection together with the effective Young’s modulus of the membrane. The perturbation method is used to derive the solution for the governing von Kármán equations. The results show that the thicker is the supporting post width, the higher is the resonant frequency. This method can also be used to simplify the mask design and CMUT fabrication process.

Phenacetin, an antipyretic and analgesic drug, poses a serious health risk to both humans and aquatic organisms, which is of concern since this micropollutant is frequently detected in various aquatic environments. However, rare pure bacterial cultures have been reported to degrade phenacetin. Therefore, in this study, the novel phenacetin-degrading strain PNT-23 was isolated from municipal wastewater and identified as a Rhodococcus sp. based on its morphology and 16S rRNA gene sequencing. The isolated strain could completely degrade 100 mg/L phenacetin at an inoculum concentration of OD600 1.5 within 80 h, utilizing the micropollutant as its sole carbon source for growth. Strain PNT-23 exhibited optimal growth in LB medium at 37 °C and a pH of 7.0 with 1% NaCl, while the optimal degradation conditions in minimal medium were 30 °C and a pH of 7.0 with 1% NaCl. Two key intermediates were identified during phenacetin biodegradation by the strain PNT-23: N-acetyl-4-aminophenol and 4-aminophenol. This study provides novel insights into the biodegradation of phenacetin using a pure bacterium culture, expands the known substrate spectra of Rhodococcus strains and presents a potential new candidate for the microbial removal of phenacetin in a diverse range of environments.

Here, a defect healing method is used to tune the height and width of the Schottky barrier at the interface between 2D metals and 2D semiconductors, leading to the realization of van der Waals rectifiers with enhanced performance.

Engineering marvels found throughout the exclusive structural features of biological surfaces have given rise to the progressive development of skin friction drag reduction. However, despite many previous works reporting forward drag reduction where the bio-inspired surface features are aligned with the flow direction, it is still challenging to achieve bidirectional drag reduction for non-morphable surface structures. Inspired by the flounder ctenoid scales characterized by tilted, millimeter-sized oval fins embedded with sub-millimeter spikes, we fabricate a bionic flounder two-tier structural surface (BFTSS) that can remarkably reduce the forward skin friction drag by ηdr = 19%. Even in the backwards direction, where the flow is completely against the tilting direction of surface structures, BFTSS still exhibits a considerable drag reduction of ηdr = 4.2%. Experiments and numerical simulations reveal that this unique bidirectional drag reduction is attributed to synergistic effects of the two-tier structures of BFTSS. The array of oval fins can distort the boundary layer flow and mitigate the viscous shear, whilst the microscale spikes act to promote the flow separation to relieve the pressure gradient in the viscous sublayer. Notably, the pressure gradient relief effect of microscale spikes remains invariant to the flow direction and is responsible for the backward drag reduction as well. The bidirectional drag reduction of BFTSS can be extensively applied in minimizing the energy consumption of ships and underwater vessels, as well as in pipeline transport.

The reconstruction and expansion project of oil reserve base often faces the excavation and blasting of the slope and undercrossing tunnel at the same time. Due to the flammable and explosive liquid storage nearby, the tight construction period, and the high requirements of collaborative construction, once the blasting accident occurs, the consequences are unimaginable. To facilitate safe and timely cooperative blasting construction of the slope and undercrossing tunnel, a vibration monitoring test of the slope and tunnel surrounding rock is conducted. The vibration response characteristics of the rock surrounding the slope and tunnel are analyzed, and a mathematical prediction model for the peak particle velocity (PPV) with consideration of the influence of the relative slope gradient (H/D) is established based on dimension analysis theory, which improves the prediction accuracy of PPV at the slope surface. ANSYS/LS-DYNA is used to establish a 3D finite element model for the slope and tunnel, and the dynamic response of the tunnel surrounding rock under blasting load is verified through field monitoring data. A linear statistical relationship between PPV and effective tensile stress (ETS) of the tunnel surrounding rock is established. The PPV safety criterion of the tunnel surrounding rock under blasting load is proposed to be 10 cm/s according to the first strength theory, and hence, the minimum safety distance from the tunnel working face to the slope surface is calculated to be 36 m. Finally, the excavation timing arrangement of the slope and tunnel is proposed, which has been successfully applied to the expansion project, and the construction period has been effectively shortened by 45 days while ensuring construction safety. The research results have great guiding significance to similar cooperative blasting excavation engineering for high slope and adjacent tunnel with safety and efficiency.

Abstract Background The acquisition of drug resistance has been considered as a main obstacle for cancer chemotherapy. Tumor protein 53 target gene 1 (TP53TG1), a p53-induced lncRNA, plays a vital role in the progression of human cancers. However, little is known about the detailed function and molecular mechanism of TP53TG1 in cisplatin resistance of NSCLC. Methods qRT-PCR analysis was used to detect the expression of TP53TG1, miR-18a and PTEN mRNA in NSCLC tissues and cells. Western blot analysis was performed to determine the protein level of PTEN and cleaved caspase-3. Cell viability and IC50 value were measured by MTT assay. Cell apoptosis was confirmed by flow cytometry assay. Subcellular fractionation assay was used to identify the subcellular location of TP53TG1. Dual-luciferase reporter assay, RNA pull down assay and RNA immunoprecipitation assay were carried out to verify the interaction between TP53TG1 and miR-18a. Xenografts in nude mice were established to verify the effect of TP53TG1 on cisplatin sensitivity of NSCLC cells in vivo. Results TP53TG1 level was downregulated in NSCLC tissues and cell lines. Upregulated TP53TG1 enhanced cisplatin sensitivity and apoptosis of A549/DDP cells, while TP53TG1 depletion inhibited cisplatin sensitivity and apoptosis of A549 cells. TP53TG1 suppressed miR-18a expression in A549 cells. Moreover, TP53TG1-mediated enhancement effect on cisplatin sensitivity was abated following the restoration of miR-18a expression in A549/DDP cells, while si-TP53TG1-induced decrease of cisplatin sensitivity and apoptosis was counteracted by miR-18a inhibitor in A549 cells. Furthermore, TP53TG1 promoted PTEN expression via inhibiting miR-18a. Finally, TP53TG1 sensitized NSCLC cells to cisplatin in vivo. Conclusion TP53TG1 increased the sensitivity of NSCLC cells to cisplatin by modulating miR-18a/PTEN axis, elucidating a novel approach to boost the effectiveness of chemotherapy for NSCLC.

'Implantable medical electronics' is an important part of modern medicine. It is widely applied to meet the needs for long monitoring time, steady transmission signal, small noise and easy controllability, by communicating with external terminals. The need for steady signal, small noise and to cause minimum damage to the host living tissues, the galvanic coupling intra-body communication has become the new wireless mode for implantable devises. In this paper we study the channel characteristics for these devices in 3 steps: i) the active field single-layer intra-body communication channel model is formulated based on Maxwell equations, and the analytical solution is derived for the potential distribution from: ii) the cylinder center to the source point and iii) from the source point to the surface. Then, using Matlab2010b simulation the potential distributions were obtained for: i) the cylindrical surface where the source point is placed, and ii) the cylinder surface. To verify correctness, a numerical solution model was formulated using the finite element method. By analyzing the two models' results, we conclude that the analytical solution model is correct. To describe channel characteristics, the signal attenuation rate was analyzed, and we found the signal attenuation was two to twenty-six dB within the detection range of the meter. Thus the communication method is superior to others and provides theoretical basis for further experiments. [ABSTRACT FROM AUTHOR]

The optical and magnetic properties of Eu-doped GaN prepared by ion implantation were reported and the effect of magnetic field on the photoluminescence (PL) behaviour was studied. The PL spectra show that the samples exhibit strong emission at around 622.0 nm. Magnetic measurement reveals ferromagnetic ordering at room temperature. There was an obvious correlation between the PL intensity and the external magnetic field. When external magnetic field of 1000Oe was applied to the sample, a decrease of roughly 24% in the peak intensity at 622 nm was observed. The mechanics of the magnetic ordering-modulated light emission of rare-earth-doped GaN films is discussed. It may have applications in producing magneto-optical devices. (Some figures may appear in colour only in the online journal) [ABSTRACT FROM AUTHOR]

BACKGROUND Simnotrelvir is an oral 3-chymotrypsin--like protease inhibitor that has been found to have in vitro activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and potential efficacy in a phase 1B trial. METHODS In this phase 2-3, double-blind, randomized, placebo-controlled trial, we assigned patients who had mild-to-moderate coronavirus disease 2019 (Covid-19) and onset of symptoms within the past 3 days in a 1:1 ratio to receive 750 mg of simnotrelvir plus 100 mg of ritonavir or placebo twice daily for 5 days. The primary efficacy end point was the time to sustained resolution of symptoms, defined as the absence of 11 Covid-19--related symptoms for 2 consecutive days. Safety and changes in viral load were also assessed. RESULTS A total of 1208 patients were enrolled at 35 sites in China; 603 were assigned to receive simnotrelvir and 605 to receive placebo. Among patients in the modified intention-to-treat population who received the first dose of trial drug or placebo within 72 hours after symptom onset, the time to sustained resolution of Covid-19 symptoms was significantly shorter in the simnotrelvir group than in the placebo group (180.1 hours [95% confidence interval {CI}, 162.1 to 201.6] vs. 216.0 hours [95% CI, 203.4 to 228.1]; median difference, -35.8 hours [95% CI, -60.1 to -12.4]; P=0.006 by Peto--Prentice test). On day 5, the decrease in viral load from baseline was greater in the simnotrelvir group than in the placebo group (mean difference [±SE], -1.51±0.14 log10 copies per milliliter; 95% CI, -1.79 to -1.24). The incidence of adverse events during treatment was higher in the simnotrelvir group than in the placebo group (29.0% vs. 21.6%). Most adverse events were mild or moderate. CONCLUSIONS Early administration of simnotrelvir plus ritonavir shortened the time to the resolution of symptoms among adult patients with Covid-19, without evident safety concerns. [ABSTRACT FROM AUTHOR]