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Flooding is a natural disaster that poses a threat to both people and the environment, necessitating proactive assessment and mitigation strategies to protect vulnerable communities and ecosystems. These measures are necessary to reduce the risk of flooding and moderate the impact of rainfall. In this study, an Analytical Hierarchy Process (AHP) was used to evaluate flood risk in a data-limited region by integrating Remote Sensing (RS) and Geographic Information System (GIS) methods. The study identified several key flood risk indicators, including topographic wetness index, elevation, slope, land cover, precipitation, distance to river, distance to road, and NDVI. The flood risk map had a score range of 8.71–30.99 %, with higher scores indicating a greater susceptibility to flooding. These scores were then used to classify the flood risk into five categories: very low, low, moderate, high, and very high. The percentages of regions falling into each category were 8.71 %, 23.52 %, 30.99 %, 22.68 %, and 14.09 % respectively. The area under the Curve (AUC) approach was used to validate the flood risk map, which showed a high degree of accuracy (0.86). The results of this study provide valuable insights for monitoring, and forecasting the probability of floods in the Dosso Region.

BackgroundDexmedetomidine has been used as a perineural local anesthetic (LA) adjuvant to facilitate the potency of erector spinal plane block (ESPB). This quantitative review aimed to evaluate whether perineural dexmedetomidine for ESPB can improve the effects of analgesia compared to LA alone.MethodsRandomized controlled trials (RCTs) that investigated the addition of dexmedetomidine to LA compared to LA alone in ESPB were included. The pain scores, duration of sensory block, the time to first analgesia requirement, postoperative morphine consumption, rescue analgesia, and dexmedetomidine-related side effects were analyzed and combined using random-effects models.ResultsA total of 823 patients from 13 RCTs were analyzed. Dexmedetomidine was used at the concentration of 0.5 μg/kg in three trials and 1 μg/kg in nine trials, and both in one trial. Both concentrations of dexmedetomidine perineurally administrated significantly reduced the rest VAS scores postoperatively at 12 h (0.5 μg/kg dexmedetomidine: MD = −0.86; 95% CI: −1.59 to −0.12; p = 0.02; 1 μg/kg dexmedetomidine: MD = −0.49; 95% CI: −0.83 to −0.16; p = 0.004), and 24 h (0.5 μg/kg dexmedetomidine: MD = −0.43; 95% CI: −0.74 to −0.13; p = 0.005; 1 μg/kg dexmedetomidine: MD = −0.62; 95% CI: −0.84 to −0.41; p

Abstract Droughts or floods are usually attributed to precipitation deficits or surpluses, both of which may become more frequent and severe under continued global warming. Concurring large-scale droughts in the Southwest and flooding in the Southeast of China in recent decades have attracted considerable attention, but their causes and interrelations are not well understood. Here, we examine spatiotemporal changes in hydrometeorological variables and investigate the mechanism underlying contrasting soil dryness/wetness patterns over a 54-year period (1965–2018) across a representative mega-watershed in South China—the West River Basin. We demonstrate that increasing rainfall intensity leads to severe drying upstream with decreases in soil water storage, water yield, and baseflow, versus increases therein downstream. Our study highlights a simultaneous occurrence of increased drought and flooding risks due to contrasting interactions between rainfall intensification and topography across the river basin, implying increasingly vulnerable water and food security under continued climate change.

Abstract Industrial robots are widely used in various industrial fields, such as handling and welding, due to their good repeat positioning accuracy. The motion error determines the absolute accuracy. For robot design, dimensional parameter errors and drive parameter errors, a mathematical model of a kinematic exponential product with error screws was proposed. The influence of different rod lengths and transmission errors on the accuracy of the end motion was analysed. A composite analysis method based on screw theory and vector method is proposed for the spatial deflection error of robot rotating joints with clearance. By using screw theory, a mathematical error model of the axial movement and spatial deflection of the joint gap was established. A mathematical model of joint space radial movement was established by using the three-dimensional vector method. Through numerical simulation, the position distribution law of the random error of the robot terminal in the workspace and the distribution of the plane projection density were obtained. By solving the attitude matrix, the distribution of each Euler angle error was obtained. A simulation test was carried out to verify the model's correctness. The calculation showed that the method is simple and correct, and the obtained error distribution characteristics are of great significance to improving robotic kinematic calibration accuracy and optimising the spatial position error distribution.

The “Grain-for-Green” project on the Loess Plateau is the largest revegetation program in the world. However, revegetation-induced land use changes can influence both water and carbon cycles, and the diverse consequences were not well understood. Therefore, the reasonability and sustainability of revegetation measures are in question. This study quantifies the impacts of revegetation-induced land use conversions on the water and carbon cycles in a typical watershed on the Loess Plateau and identifies suitable areas where revegetation of forest or grassland could benefit both soil and water conservation and carbon sequestration. We used a coupled hydro-biogeochemical model to simulate the changes of a few key components in terms of water and carbon by designing a variety of hypothetical land use conversion scenarios derived from revegetation policy. Compared to the baseline condition (land use in 2000), both sediment yield and water yield decreased substantially when replacing steep cropland with forest or grassland. Converting cropland with slopes larger than 25°, 15°, and 6° to forest (CTF) would enhance the carbon sequestration with a negligible negative effect on soil water content, while replacing cropland with grassland (CTG) would result in a decline in net primary production but with a substantial increase in soil water content (3.8%–14.9%). Compared to the baseline, the soil organic carbon would increase by 0.9%–3.2% in CTF and keep relatively stable in CTG. Through testing a variety of hypothetical revegetation scenarios, we identified potential priority areas for CTF and CTG, where revegetation may be appropriate and potentially beneficial to conserving soil and water and enhancing carbon sequestration. Our study highlights the challenges in future water and carbon coupling management under revegetation policy, and our quantitative results and identification of potential areas for revegetation could provide information to policy makers for seeking optimal management on the Loess Plateau.

Introduction: Periodontitis is a chronic inflammatory disease brought on by various bacteria, and effective antibacterial, anti-inflammatory and alveolar bone regeneration are the main goals of treating periodontal disease.Methods: In the current work, we employed Icariin (ICA) into a hydrogel modified with carbon nanofiber (CNF) to create a multifunctional composite nanoplatform. The composite was activated in the near infrared (NIR) to treat periodontitis.Results: The antibacterial results showed that the ICA+CNF@H showed 94.2% and 91.7% clearance of S. aureus and E. coli, respectively, under NIR irradiation. In vitro experiments showed that NIR-irradiated composites suppressed inflammatory factor (IL-6) and ROS expression and up-regulated the performance of anti-inflammatory factor (IL-10) in RAW264.7 cells. At the same time, the composites promoted the production of osteogenic factors in BMSCs, with an approximately 3-fold increase in alkaline phosphatase activity after 7 days and an approximately 2-fold increase in the rate of extracellular matrix mineralization after 21 days. In vivo tests showed that the alveolar bone height was clearly greater in the ICA+CNF@H (NIR) group compared to the periodontitis group.Discussion: In conclusion, ICA+CNF@H under NIR irradiation achieved a synergistic effect of antibacterial, anti-inflammatory, reduction of reactive oxygen species and promotion of osteogenesis, offering a novel approach for treating periodontitis.

Study region: Upper Heihe River Basin, Northwest China. Study focus: We investigated potential climate change under three Representative Concentration Pathways (RCP 2.6, 4.5, and 8.5) and their impacts on frozen ground in the upper Heihe River Basin using the ensemble climate data from eight general circulation models and the Soil and Water Assessment Tool (SWAT). New hydrological insights for the region: Air and ground freezing indices declined significantly during the baseline period (1976–2015), whereas the thawing indices increased, indicating the heat accumulation in study area. The frost depth, which refers to the potential frost depth of active layer in permafrost areas and the maximum frost depth in seasonally frozen areas, decreased significantly at the rate of 3 cm/10 yr. The SWAT-simulation and gray relational analysis revealed that soil water was controlled by precipitation and frost depth in spring and autumn. Compared to that of the baseline, the projected frost depth is projected to decline by 0.07–0.1 m during the near future (2020–2059) and 0.08–0.36 m for the far future (2060–2099). In addition, we developed a long-term warning system, which indicates that the degree of frozen ground degradation would be mild during the near future and would be severe for the far future under RCP 8.5. This study provides valuable insights into the protection of frozen-ground in the Upper Heihe River Basin.

Potential evapotranspiration (PET) is an important part of drought monitoring and evaluation. It is very important to analyze the climatic sensitive factors of PET to reveal the mechanism of hydrological responses to climate change. However, the local sensitivity method commonly used in previous studies is not suitable for nonlinear models and it is difficult to evaluate the interaction among meteorological factors. In this study, based on the monitoring data of 163 meteorological stations in the arid and semi-arid areas of northwest China from 1964 to 2018, we use the Penman-Monteith equation and Sobol global sensitivity to analyze the climatic sensitive factors of PET in the study area and discuss the climatic causes of the PET change. We also calculate the scPDSI and analyze the evolution characteristics of drought in northwest China. The results show that the annual average PET of the study area is 1157.8 mm with substantial spatial variations. The high-value areas are located in the eastern part of Xinjiang and the western part of Inner Mongolia, and the low-value areas are located in the southern part of Qinghai Province. The year 1993 was identified as a turning point, and the PET changed from a significant downward trend to a significant upward trend, which was more apparent in the summer in that year. From 1964 to 1993, the net radiation, wind speed, and relative humidity had a relatively greater impact on PET, while in the period 1994-2018, wind speed and relative humidity had a relatively greater impact on PET. The spatio-temporal distribution of scPDSI show that the drought in northern Xinjiang, central Qinghai and Gansu is becoming less severe, while the drought severity in the southwest part of the Yellow River Basin is becoming more severe, exacerbating regional water resources shortage and threatening ecological security.

Background. Many researches revealed that microRNAs (miRNAs) function as potential oncogene or tumor suppressor gene. As an antioncogene, miR-877-5p was reduced in many tumors. Objective. This research aimed to explore the biological role and mechanisms of miR-877-5p, which may help patients with non-small-cell lung cancer (NSCLC) find effective therapeutic targets. Methods. The downstream targets of miR-877-5p were predicted by Bioinformatics software. RT-qPCR and western blot were employed to analyze the gene levels. The impacts of miR-877-5p and FOXM1 were assessed by cell function experiments. Results. The miR-877-5p was reduced in NSCLC. In addition to this, it also inhibited cell progression of NSCLC cells in vitro. Moreover, the upregulation of FOXM1 expression restored the inhibitory effect of enhancement of miR-877-5p. Conclusions. Taken together, miR-877-5p inhibited cell progression by directly targeting FOXM1, which may provide potential biomarkers for targeted therapy of NSCLC.

Calvin cycle is a sequence of enzymatic reactions that assimilate atmospheric CO2 in photosynthesis. Multiple components are known to participate in the induction or suppression of the Calvin cycle but the mechanism of its regulation by phytohormones is still unclear. Brassinosteroids (BRs) are steroid phytohormones that promote photosynthesis and crop yields. In this study, we study the role of BRs in regulating Calvin cycle genes to further understand the regulation of the Calvin cycle by phytohormones in tomatoes. BRs and their signal effector BRASSINAZOLE RESISTANT 1 (BZR1) can enhance the Calvin cycle activity and improve the photosynthetic ability. BRs increased the accumulation of dephosphorylated form of BZR1 by 94% and induced an 88–126% increase in the transcription of key genes in Calvin cycle FBA1, RCA1, FBP5, and PGK1. BZR1 activated the transcription of these Calvin cycle genes by directly binding to their promoters. Moreover, silencing these Calvin cycle genes impaired 24-epibrassinolide (EBR)-induced enhancement of photosynthetic rate, the quantum efficiency of PSII, and Vc,max and Jmax. Taken together, these results strongly suggest that BRs regulate the Calvin cycle in a BZR1-dependent manner in tomatoes. BRs that mediate coordinated regulation of photosynthetic genes are potential targets for increasing crop yields.

The metallurgical property of sinter is an important factor affecting the smooth operation of blast furnaces (BF), because it has a great impact on the permeability of BF and solid fuel rate. In order to promote the combustion of solid fuel and the mineralization of flux in sintering process, and eventually improve the strength of sintered ore, a series of investigation on segregation granulation by fuel and flux in coating were carried out, including the sinter pot experiments, the morphology analysis, and the discussion combine with phase diagram. The experimental results show that, (1) as the CaO increased from 0% to 40% and coke breeze increased from 0% to 100%, the sintering indices were improved, the tumble strength of sinter increased from 65.8% to 68.4%, the rate of qualified products increased from 77.4% to 81.0%, and the micro-strength of sinter increased from 68.7% to 75.9%. (2) There are three reasons for the high strength of sinter by segregation granulation of fuel and flux in coating, (a) the complete combustion of solid fuel and release the heat, (b) the effective absorb heat and mineralization of flux, and (c) the improvement of fluidity of bonding phase. The outcomes of the present work may provide a new method to improve the strength of sintered ore and give some reference for better understanding segregation granulation process and using it in actual operation.

High-speed trains have a large amount of ancillary equipment, which is suspended from the underside of the train by means of a suspension structure. Due to the large mass of the ancillary equipment, the suspension structure is subjected to various loads during train operation and there is a risk of fatigue failure. In this paper, the stress distribution at the suspension point and the lo-cation of the maximum stress point under load are investigated in detail based on actual test loads at the suspension point and finite element simulation analysis. In order to further investigate the fracture failure of the suspension points, experimental studies were carried out. Firstly, static strength tests were carried out to obtain the load–displacement curves of the structural members and to determine the fracture strength of the structure based on the displacement sensors, and secondly, fatigue tests at different stress levels were carried out to obtain the load–life curves of the structural members and to investigate the probabilistic load–life curves at different reliability levels. The test results show that the structural component has a high fracture strength of 65kN, while the conditional fatigue strength is relatively low, corresponding to a load level of 12.5kN at a median life of 106 cycles. The above research work provides the necessary basis for the design, optimization and reliability assessment of the suspension structures of high-speed trains.

Quantifying the impacts of vegetation restoration (VR) on energy exchange is essential for exploring climate-vegetation interactions. Due to the complexity of land–atmosphere energy exchange and limited observation networks, the influence of VR on the energy balance remains unclear. To improve the understanding of the energy budget change associated with VR in the Loess Plateau (LP), we performed a series of sensitivity simulation experiments using the Community Land Model within the Community Earth System Model, and the spatiotemporal responses of energy exchange to VR and the roles of VR in the variations in energy budget under climate change were investigated. The results showed that the land cover changes from 2000 to 2015 exerted a positive effect on net radiation (NR) and sensible heat (SH), and evident increases in annual mean NR and SH were found in the southeastern LP where larger-scale cropland was converted to grassland or forestland, with increasing magnitudes exceeding 2 W/m2. Latent heat (LH) increased only during May–July, particularly on the southern edge of LP. The increasing magnitudes of NR and LH under Representative Concentration Pathway (RCP)8.5 were larger than those under RCP4.5, with the greatest differences being approximately 4 W/m2 and 5 W/m2 during 2081–2100 for NR and LH, respectively. SH remained nearly stable under RCP4.5 and showed a weak decrease under RCP8.5. Under the same RCP, only slight differences in the energy budget components were detected between the land cover condition in 2015 and 2000, with the largest difference of 0.8 W/m2 in SH during 2021–2040. These results suggested that although both VR and climate warming exerted positive effects on NR, the impact of climate change was larger than that of VR in the LP, and a shift in the local surface energy budget toward LH would occur with climate warming.

The clearance of a kinematic pair will lead to the contact collision between the joints of the mechanism, which will have a great influence on the dynamic characteristics of a mechanical system with clearance. In order to study the influence of a rotating motion pair with clearance on the dynamic characteristics of a tool changing robot, a contact wear dynamics model of a modular tool changing robot was established based on the three-state model of “free-contact-collision”. Different from analysis of a light linkage structure, this paper takes a solid structure with large mass as the analysis object. Based on the impact contact force model and the improved Coulomb friction model, the effects of clearance size, rotational speed and friction coefficient on the dynamic characteristics of the tool changing robot were analyzed. The Archard wear model was used to predict the wear between the motion pairs with clearance. The analysis results show that, with the increase of clearance size and actuating speed, the fluctuation range of velocity and acceleration increases, and the fluctuation frequency decreases. Under the action of friction, the contact force between components will be reduced due to energy loss so that the kinematic reliability of the mechanism is improved. The wear of the moving pair with clearance is non-uniform. Through the research of this paper, the motion characteristics of the tool-changing robot at low speed and heavy load are clarified. The results show that the established method can realize the dynamic characteristics analysis of low-speed heavy-duty mechanisms with joint gaps, which can be used to guide the design of tool-changing robots, and also has important reference significance for the design of mechanisms containing joint gaps in general.

This paper presents theoretical studies of Fano resonance based electric-field (E-field) sensors. E-field sensor based on two electro-optical (EO) materials i.e., barium titanate (BaTiO3, BTO) nanoparticles and relaxor ferroelectric material Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) combined with nanostructure are studied. As for the BTO based E-field sensor, a configuration of filling the BTO nanoparticles into a nano-patterned thin film silicon is proposed. The achieved resonance quality factor (Q) is 11,855 and a resonance induced electric field enhancement factor is of around 105. As for the design of PMN-PT based E-field sensor, a configuration by combining two square lattice air holes in PMN-PT thin film but with one offsetting hole left is chosen. The achieved resonance Q is of 9,273 and an electric field enhancement factor is of around 96. The resonance wavelength shift sensitivity of PMN-PT nanostructured can reach up to 4.768 pm/(V/m), while the BTO based nanostructure has a sensitivity of 0.1213 pm/(V/m). If a spectrum analyzer with 0.1 pm resolution is considered, then the minimum detection of the electric field Emin is 20 mV/m and 0.82 V/m for PMN-PT and BTO based nanostructures, respectively. The nano-patterned E-field sensor studied here are all dielectric, it has therefore the advantage of large measurement bandwidth, high measurement fidelity, high spatial resolution and high sensitivity.

Exercise is believed to have significant cognitive benefits. Although an array of experimental paradigms have been employed to test the cognitive effects on exercising individuals, the mechanism as to how exercise induces cognitive benefits in the brain remains unclear. This study explores the effect of dynamic neural network processing with the classic Go/NoGo task with regular exercisers. We used functional magnetic resonance imaging to analyze the brain activation of areas involved in executive function, especially inhibitory control. Nineteen regular joggers and twenty-one subjects as a control group performed the task, and their brain imaging data were analyzed. The results showed that at the attentive visual period, the frontal and parietal areas, including the prefrontal cortex, putamen, thalamus, lingual, fusiform, and caudate, were significantly enhanced in positive activities than the control group. On the other hand, in the following inhibitory control processing period, almost the same areas of the brains of the exercise group have shown stronger negative activation in comparison to the control group. Such dynamic temporal response patterns indicate that sports augment cognitive benefits; i.e., regular jogging increases the brain’s visual attention and inhibitory control capacities.

ObjectivesDental pulp regeneration is considered an ideal approach for treating dental pulp disease. Because pulp is composed of various cells, determining the proper seed cells is critical. We explored the potential of human umbilical cord mesenchymal stem cells (hUCMSCs) as seed cells for dental pulp regeneration.MethodsLiquid extract of human treated dentin matrix (LE-TDM) was acquired to culture hUCMSCs. Odontoblast-specific markers were detected by western blot, qRT-PCR, and immunofluorescence assays. Endothelial differentiation of hUCMSCs was examined according to VEGF induction by western blot, qRT-PCR, and Matrigel assays. hUCMSCs and VEGF-induced hUCMSCs (V-hUCMSCs) were also cocultured in vivo for the Matrigel plug assay and in vitro for RNA-sequencing (RNA-seq). Finally, encapsulated mono-cultured hUCMSCs or cocultured hUCMSCs and V-hUCMSCs in scaffolds were injected into the root segments and transplanted into immunodeficient mice for dental pulp regeneration.ResultsUnder LE-TDM induction, hUCMSCs expressed specific odontoblast markers (DSPP, DMP-1, DSP). Under VEGF induction, hUCMSCs expressed functional endothelial markers (CD31, eNOs, vWF). In vivo, the Matrigel plug assay indicated that cocultured hUCMSCs and V-hUCMSCs formed extensive vessel-like structures. RNA-seq results indicated that cocultured V-hUCMSCs exhibited high Hif-1 signaling pathway activity. Both the hUCMSCs mono-culture and coculture groups showed pulp-like tissue regeneration. The cocultured group showed more extracellular matrix and vascularization than the mono-cultured group in vivo.ConclusionhUCMSCs can differentiate into odontoblast-like cells and functional endothelial cells. Cocultured hUCMSCs and V-hUCMSCs formed vessel-like structures and regenerated dental pulp-like tissue. Therefore, hUCMSCs can be used as an alternative seed cell source for angiogenesis and dental pulp regeneration.

The effects of Ge occupations at Sb and Mn sites in Mn2Sb system had been re-examined along with the influence of hydrostatic pressure. The metamagnetic phase transition from ferrimagnetic (FRI) to antiferromagnetic (AFM) state was observed in Mn2Sb1-xGex (x = 0.05, 0.1) and (Mn1-yGey)2Sb (y = 0.025, 0.04) alloys. The phase transition temperature, Tt, was gradually increased with increased Ge substitution for both Sb and Mn, but slightly decreased under increased hydrostatic pressure in Mn2Sb0.95Ge0.05 alloy. Meanwhile, the slope of critical field as the function of temperature was reduced with increased hydrostatic pressure and Ge substitution amount in (Mn1-yGey)2Sb (y = 0.025, 0.04) alloys. For a field change of 7 T, the maxima of magnetic entropy changes of 6 Jkg-1K-1 and 7.1 Jkg-1K-1 have been achieved in Mn2Sb0.95Ge0.05 and Mn1.95Ge0.05Sb alloys, which are gradually decreased by more Ge substitution and increased hydrostatic pressure.

The magnetic properties and magnetocaloric effect (MCE) of Gd4Sb3-xRx (R = Si, Ge, Sn, x = 0, 0.25, 0.5, 0.75) compounds have been studied systematically. The Curie temperature (Tc) of these compounds can be tuned from 270 K to 305 K depending on the substitution amount. All the compounds undergo a second-order magnetic transition from ferromagnetic (FM) state to paramagnetic (PM) state and exhibit considerable reversible MCE near room temperature. The maximum of magnetic entropy change (ΔSMmax) for a magnetic field change of 7 T can reach 4.25 Jkg-1K-1 in Gd4Sb3 phase and independent on Si substitution amount. By Ge and Sn substitution, reduced ΔSMmax of 3.5 and 4.25 Jkg-1K-1 can be obtained in Gd4Sb2.75Ge0.25 and Gd4Sb2.75Sn0.25 alloys respectively. The considerable MCE with no hysteresis and working temperature near room temperature suggests that these materials could be promising candidates as ambient magnetocaloric materials.

The oxidation of Ca-α-SiAlON synthesized by the combustion synthesis (CS) method with different additives was investigated in air atmosphere using thermogravimetric (TG) analysis in a temperature range from 1453 K to 1653 K. The experimental results indicated that oxidation was controlled by mixed chemical and diffusion steps. The oxidation products by XRD analysis were composed of SiO2 and CaAl2Si2O8 at low oxidation temperature, whereas the SiO2-Al2O3-CaO ternary glassy phase was formed at elevated temperature. The deviation of oxidation resistance from each sample may be due to the morphological difference brought about by different additive additions. This study reveals the effects of additives on the oxidation resistance of synthesized Ca-α-SiAlON powders.

PURPOSE:Tissue inhibitor of metalloproteinase-1 (TIMP-1) is a glycoprotein involved in cell survival and tumorigenesis. There have been some promising results regarding the diagnostic value of TIMP-1 for patients with colorectal cancer (CRC). The aim of the present study was to assess the diagnostic accuracy and clinical utility of serum TIMP-1 in CRC patients through meta-analysis. METHODS:A systematic search of online databases was performed to collect eligible studies. The pooled sensitivity, specificity, diagnostic odds ratio (DOR), and summary receiver operator characteristic (SROC) curve were generated from accuracy data using the random-effects model. Fagan's nomogram and the likelihood matrix were applied to estimate the clinical utility of TIMP-1. RESULTS:A total of 9 eligible studies with 1886 patients were included. Among the patients, 819 were pathologically diagnosed with CRC, whereas 1067 did not have adenomas or other cancers. The overall sensitivity, specificity, and DOR of TIMP-1 for the diagnosis of CRC were 0.65 (95% confidence interval (CI): 0.57-0.72), 0.87 (95% CI: 0.76-0.94), and 12.73 (95% CI 5.71-28.38), respectively. The area under the SROC was 0.77 (95% CI, 0.73-0.81), suggesting the potential diagnostic value of TIMP-1 in CRC patients. Among patients with a pretest CRC probability of 20%, posttest probabilities were 56% and 9% for positive and negative TIMP-1 results, respectively. CONCLUSIONS:TIMP-1 expression exhibits an upper moderate diagnostic value in CRC, and TIMP-1 assessment may be useful as a noninvasive screening tool for CRC in clinical practice.

A broadband microwave absorbing composite with a multi-scale layered structure is proposed, in which a reduced graphene oxide (RGO) film sandwiched between two layers of epoxy glass fiber laminates serves as the frequency selective surface (FSS). RGO films with the desired electrical properties were synthesized directly by hydrothermal reaction, vacuum filtration, and heat treatment without subsequent processing. With the novel layer-by-layer structure ranging from micro to macro scale, the optimized composite exhibits excellent microwave absorption performance with a total thickness of 3.2 mm. Its reflection coefficient (RC) is less than −10 dB in the entire X and Ku band, reaching a minimum value of −32 dB at 10.2 GHz and an average RC of −22.8 dB from 8 to 18 GHz. Enhanced microwave absorption of the composites is achieved through the optimization of layer thickness in the sandwich structure to promote destructive interference. Improved impedance matching by the introduction of FSS along with the polarization and conduction loss of layered graphene films also contribute to the increased absorption.

In this work, the self-healing Si-B-C matrix-modified ZMI-SiC fiber/SiC (SiC/SiC-SiBC) composite was prepared by a combined process of chemical vapor infiltration, slurry infiltration, and liquid silicon infiltration. The weight changes of the as-fabricate composite after oxidation at 800, 1000, and 1200 °C for 100 h were −0.41%, −0.06%, +0.05%, respectively. The corresponding strength retention ratios were 75%, 99%, 100%, respectively. With the increase of oxidation temperature, coating cracks would be closed. A dense oxidation film was formed with the oxidation of the SiBC matrix, preventing the oxidation of interphase and fiber and leading to excellent oxidation resistance at 1000 and 1200 °C.

The harsh environmental loads may lead to strength failure in the turbine in an aero-engine. To accurately assess the strength reliability of the turbine under multiple loads, the stress distributions of 41 danger sites of a turbine under thermal, centrifugal, and pneumatic loads were determined by the flow-thermal-solid coupling analysis using ANSYS. Second, based on the flow-thermal-solid coupling analysis and response surface method, the probabilistic analysis model of stress at the danger site was established. And the probabilistic distribution of stress was determined by sampling and hypothesis testing. Finally, the reliability model of the turbine with multi-site damage and failure dependency was established, by which a reliability of 0.99802 was calculated. And the actual reliability of the turbine was 0.99626 determined by the Monte Carlo simulations, which verified the model in precision. The results indicated that the reliability model has a high efficiency and higher precision than the traditional reliability model with failure independence. [ABSTRACT FROM AUTHOR]