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Nowadays, biopolymer stabilization as a promising eco-friendly approach in soft ground improvement has attracted wide attentions. However, the feasibility of using biopolymer as a green additive of cement-stabilized dredged sediment (CDS) with high water content is still unknown. In this study, guar gum (GG) and xanthan gum (XG) were adopted as typical biopolymers, and a series of unconfined compressive strength (UCS), splitting tensile strength (STS) and scanning electron microscopy (SEM) tests were performed to evaluate the mechanical and microstructural properties of XG- and GG-modified CDSs considering several factors including biopolymer modification, binder–soil ratio and water–solid ratio. Furthermore, the micro-mechanisms revealing the evolutions of mechanical properties of biopolymer-modified CDS were analyzed. The results indicate that the addition of XG can effectively improve the strength of CDS, while the GG has a side effect. The XG content of 9% was recommended, which can improve the 7 d- and 28 d-UCSs by 196% and 51.8%, together with the 7 d- and 28 d-STSs by 118.3% and 42.2%, respectively. Increasing the binder–soil ratio or decreasing the water–solid ratio significantly improved the strength gaining but aggravated the brittleness characteristics of CDS. Adding XG to CDS contributed to the formation of microstructure with more compactness and higher cementation degrees of ordinary Portland cement (OPC)-XG-stabilized DS (CXDS). The micro-mechanism models revealing the interactions of multiple media including OPC cementation, biopolymer film bonding and bridging effects inside CXDS were proposed. The key findings confirm the feasibility of XG modification as a green and high-efficiency mean for improving the mechanical properties of CDS.

Calcium sulphoaluminate cement (CSA) is considered a sustainable alternative to traditional Portland cement to reduce CO2 emissions. To further improve the hardening properties and water resistance of CSA and advance its extensive special engineering application, nanoparticles including nano-SiO2 (NS), nano-MgO (NM) and nano-Al2O3 (NA) were used as nano-modifiers for CSA. The effects of nanoparticles dosage on the setting time, compressive strength and water resistance of nano-modified CSA were experimentally evaluated, and the micro-mechanisms were also clarified by conducting X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TG) tests. The results showed that incorporating nanoparticles into CSA obviously shortened the initial and final setting times. The appropriate addition of nanoparticles effectively enhanced the compressive strength of CSA, and the optimum dosages of NS, NM, and NA were respectively determined to be 0.5 %, 1.0 %, and 0.5 %. Water immersion decreased the bonding strength of CSA, and adding nanoparticles can effectively weaken this water-induced deterioration effect. Under water immersion environment, the optimum dosages of nanoparticles would be increased to obtain the highest residual water immersion strength and minimum strength loss rate. The generation of ettringite was mainly responsible for the compressive strength and water resistance improvements of nano-modified CSA. The hydration process of nano-modified CSA was clarified and the corresponding micro-mechanism model was proposed. Furthermore, the benefits and challenges of using nano-modified CSA were also analyzed, advancing its widespread application in rapid repair of special engineering.

Objective To explore the clinical efficacy and imaging changes of minimally invasive nonsurgical periodontal therapy (MINST) assisted by endoscopy for deep intrabony defects and to compare its effectiveness with that of traditional scaling and root planning (SRP) to therefore provide a reference for clinical periodontal treatment. Methods Patients with deep intrabony defects ≥ 4 mm in size were selected and divided into two groups: the MINST (MINST, 20 cases, 81 sites) group and the classic scaling and root planing (SRP, 20 cases, 80 sites) group. Before treatment and 12 and 24 months after treatment, probing depth (PD) and clinical attachment loss (CAL) were examined. Moreover, changes in the depth and angle of the intrabony defects were analyzed. Follow-up examination and maintenance treatment should be conducted every 3 months for 12 months after the initial treatment and every 6 months thereafter until 24 months. Results The PD and CAL of patients in both groups continued to decrease (P

High-efficiency disposal of dredged sediment (DS) has become an imperative geo-environmental engineering issue due to the limited landfilling space and severe environmental burdens. This study firstly developed a novel high-efficiency nano-modified and chemical-activated binary cement (NBC), which was composed of binary cement (BC) consisting ordinary Portland cement (OPC) and ground granulated blast-furnace slag (GGBS), chemical-activator and nano-modifier. The effects of chemical-activation and nano-modification on the strength development of BC-stabilized DS (BCDS), and the optimum mix of NBC were respectively achieved via a series of unconfined compressive strength and orthogonal tests. Then, the high-efficiency and economic applicability of NBC in DS stabilization were evaluated by comparing with OPC. Furthermore, the microstructure and mineral composition evolutions inside NBC-stabilized DS (NDS) were explored by conducting X-ray diffraction (XRD) and scanning electron microscopy (SEM) tests. The results show that both chemical-activation and nano-modification could effectively improve the strength gain of BCDS, and compared with single chemical-activator and nano-modifier, the composite chemical-activators and nano-modifiers exhibited better performances. Based on BC with OPC/GGBS mass ratio of 1:1, both anhydrous sodium metasilicate/anhydrous sodium sulfate (SM/SS) and nano-SiO2/nano-MgO (NS/NM) with mass ratio of 1:9 were respectively determined to be optimum chemical-activator and nano-modifier. The optimum mass ratio of BC, SM/SS and NS/NM was 20:2:1, i.e. the optimum mix of NBC. Compared with OPC, NBC exhibited higher stabilization efficiency and better economic applicability. The generation of calcium silicate hydrate (CSH), calcium aluminate hydrate (CAH) and ettringite contributed to the formation of dense cemented soil matrix inside NDS, and a conceptual micro-mechanism model characterizing the strength development under the coupling action of chemical-activation and nano-modification was proposed.

The low reactivity and high stability of waste concrete powder (WCP) hinder the promotion of recycled binder applications with WCP addition. This study provides an innovative utilization strategy for thermal-modified WCP (TMWCP) recycling as an environmentally friendly solidification/stabilization (S/S) binder material for Pb-contaminated soil by adding ground granulated blast furnace slag (GGBS). The S/S treated soils underwent performance evaluations including unconfined compressive strength and leaching tests. Furthermore, the X-ray diffraction, scanning electron microscopy, and mercury intrusion porosimetry tests were conducted to elucidate the underlying mechanisms. The results show that at an optimal heat treatment temperature of 600 °C for WCP, the S/S treated soil achieved a compressive strength of 4.2 MPa after 28 d of curing. Additionally, the optimum mixture ratio of TMWCP and GGBS was 9:1. It was found that the novel binder was much superior to OPC in terms of Pb immobilization and carbon emission reduction. When the dosage of the formed binder is twice that of OPC, it can compensate for the lack of strength in S/S treated Pb-contaminated soil.

Cement-based solidification is a widely used sustainable technology for transforming waste dredged sludge (DS) into backfill materials. This study developed a novel solidification/oxidization synergistic (SOS) method, using Portland cement as a binder and sodium persulfate (SP) as an oxidant, for treating the organic DS with different fulvic acid (FA) content. The results demonstrated that adding SP could significantly improve the UCS of the cement-solidified DS doped with FA. When the FA content was 4%, the 28-day UCS of the sample with 25% cement content was only 160.5 kPa. The addition of 6% SP increased the UCS to 2225.5 kPa, which was 15.1 times that of the sample without SP. However, excessive SP hydrolyzed to produce a large amount of sulfuric acid, leading to a low pH value of the pore solution. This in turn hindered further persulfate activation and cement hydration, which was detrimental to the strength of cement-solidified DS.

Objective To evaluate the value of single or combined detection of procalcitonin (PCT), interleukin-6 (IL-6), serum amyloid A (SAA) and c-reactive protein (CRP) in the differential diagnosis of simple and strangulated intestinal obstruction. Methods This retrospectively study collected 61 patients with intestinal obstruction. The patients were classified into the group of simple or strangulated intestinal obstruction according to operation. The age, sex, basic diseases, lesion sites and inflammatory indicators such as PCT, IL-6, SAA and CRP in two groups were collected and analyzed. The Students’ T-test and the Mann-Whitney U test were used to analyze normally and non-normally distributed data, respectively. The categorical variable was analyzed by the chi-square test. The receiver-operating characteristic (ROC) curve and the area under the curve (AUC) were used to predict the differential diagnostic value of single and combined detection of the above clinical inflammatory indicators. Results The serum levels of PCT, IL-6, SAA and CRP of the strangulated group were significantly higher than those of the simple group ( p < .05). The areas under the ROC curve (AUC) were 0.907 for PCT, 0.712 for IL-6, 0.723 for SAA and 0.681 for CRP. With the cutoff values of PCT (0.24 ng/L), IL-6 (19.55 pg/L), SAA (282.50 mg/L) and CRP (63.00 mg/L), the sensitivity and specificity were 86.40% and 87.20% for PCT, 68.20% and 76.90% for IL-6, 59.10% and 87.20% for SAA, 63.60% and 87.20% for CRP, respectively. And the sensitivity and specificity were 86.40% and 89.70% for combined model. The differences between PCT and the combined model are tiny and neither clinically nor statistically significant. Conclusions For discriminating strangulated intestinal obstruction from simple intestinal obstruction, PCT alone may be the preferred approach due to its simplicity.

The combination of chemical stabilization and fiber reinforcement can simultaneously improve the strength and ductility of dredged sediment. The polypropylene fiber (PF) and straw fiber (SF) were respectively used as artificial and natural reinforcements of cement-stabilized dredged sediment (CDS). A series of unconfined compressive strength (UCS) tests were conducted to investigate the effects of cement content, fiber content, fiber length and water content on the mechanical properties of PF-reinforced CDS (CPFDS) and SF-reinforced CDS (CSFDS). Furthermore, the cementation-reinforcement mechanism was explored and analyzed via macro failure characteristics and micro interfacial morphologies inside typical CPFDS and CSFDS samples. The results showed that increasing cement content or decreasing water content significantly improved the UCS and aggravated the brittleness of CPFDS and CSFDS. The suitable addition of PF can effectively improve the UCS of CDS, while incorporating SF exhibited the opposite role. The maximum 7d-, 28d-, 60d- and 90d-UCS of CPFDS were respectively 17.7%, 43.6%, 10.7% and 9.7% higher than that of CDS. The optimum length of PF inside CPFDS and SF inside CSFDS was 3 mm and 5–10 mm, respectively. Both incorporating PF or SF can effectively improve the ductility of CDS. Based on the proposed parameters of total-water/cement ratio and fiber cementation factor, the effective strength development models of CPFDS and CSFDS considering cement content, fiber content, water content and curing time were empirically established. The fiber “bridge” effect and interfacial friction between fiber and cemented soil particles were mainly responsible for the strength evolution and ductility improvement of CPFDS and CSFDS.

Abstract A wide array of microRNAs (miRNAs) is differentially expressed in breast tumors and also functions as tumor suppressors. Herein, the current study sought to unravel the function of miR-4731-5p in breast cancer progression. First, breast cancer-related miRNA and mRNA microarray data sets were retrieved for differential analyses. Subsequently, the expression patterns of miR-4731-5p, PAICS, and FAK in breast cancer tissues and cells were determined, in addition to analyses of their roles in glycometabolism, migration, invasion, epithelial–mesenchymal transition (EMT) analyzed through functional assays. Next, the targeting relation between miR-4731-5p and PAICS was validated. Xenograft tumors in nude mice were further established to reproduce and verify the in vitro findings. miR-4731-5p was poorly expressed and PAICS was highly expressed in breast cancer tissues and cells. PAICS was confirmed as a target of miR-4731-5p. Moreover, miR-4731-5p exerted an inhibitory effect on glycolysis, EMT, migration, and invasion in breast cancer cells via regulation of PAICS-dependent phosphorylation of FAK. In vivo assay further validated the significance of the miR-4731-5p/PAICS/FAK axis in vivo tumorigenesis and lung metastasis in breast cancer. Collectively, our findings indicated that miR-4731-5p inhibited breast cancer cell glycolysis and EMT through the reduction of PAICS-induced phosphorylation of FAK.

Recently, research on the application of unmanned aerial vehicle (UAV) in wireless communication networks has been widely studied.Aiming at the downlink wireless transmission system of UAV assisted mobile user communication, a method of resource allocation and trajectory optimization based on user route was proposed.According to the known user route, the estimated large-scale channel state information was obtained in advance, and a joint optimization problem of communication bandwidth allocation and trajectory optimization was established to maximize the minimum average rate of users.The problem was a nonconvex optimization problem, and there was nonlinear coupling between the variables.By introducing the method of alternating optimization of auxiliary variables and separated variables, the original problem was decomposed into two approximate convex optimization subproblems which could be solved, and the successive convex approximation was used to iteratively optimize the two subproblems, and an approximate suboptimal solution of the original nonconvex problem was obtained.Simulation results show that the proposed method of resource allocation and trajectory optimization can effectively improve the average data throughput of users, and improve the efficiency of UAV assisted communication on the premise of ensuring the communication quality of all users.

In this study, a novel impervious sand is modified from the desert sand. It has a good waterproofing and thermal-isolating capacity. Hence. it was used as the separation layer in the collapsible losses embankment to prolong the service life. It has the advantages of lightweight, good waterproofing effect, and cycled usage. The application of impervious sand in collapsible losses embankment could constrain water immigration effectively. Hence, local collapsible losses could be used in highway construction, which means the construction cost could be saved to a large extent. In this study, an artificial fill and impervious sand of different thicknesses were both used in collapsible losses embankment. In-suit monitoring on soil temperature, water content, settlement, and strains of different directions were conducted for more than one year. Hence, the waterproofing effect between the artificial fill and impervious sand could be compared. Furthermore, the collapsible losses embankment side slope stability was calculated through a finite element model. The long-term performance of embankment stability, which took the filling loess’s water content into consideration, was also calculated and compared between the separation layer made of artificial fill or impervious sand.

This paper presents a novel miniaturization 90° phase shifter using parallel coupled inductors and capacitors. The size reduction is achieved by replacing the quarter-wavelength transmission lines in a conventional fixed 90 degrees phase shifter with the resonator circuit. The resonator circuit, formed by the parallel coupled inductors and capacitor, provides a 90° phase shift at 45 MHz. In this way, the circuit size can be largely reduced without sacrificing the operation bandwidth and power handling. The inductors structure used in the phase shifter carries high power, which consists of two full coupled rectangle metal coils. The proposed miniature fixed phase shifter is then applied to the design of a directional coupler centered at 45 MHz. The measured results show a bandwidth of 40-50 MHz for better than 35 dB return loss with a phase shift of ~90°, a deviation within ~2°, and power handling of 63 dBm (2 kW). Notably, the proposed fixed phase shifter occupies an area of 58.5 mm × 30.5 mm × 33 mm, which is only about 0.009 λ0 × 0.0045 λ0 × 0.005 λ0 at 45 MHz.

Based on the aeroengine lubricating oil system test bench, this paper used a dimensional analysis method to establish a mathematical model for predicting the separation efficiency and resistance of a dynamic pressure oil-air separator suitable for engineering. The analysis of the multivariate nonlinear fitting error and the experimental data showed that the established separation efficiency and resistance model could accurately predict the separation and resistance performance of the dynamic pressure oil-air separator within a certain range; the average error of the four separation characteristic prediction models was 3.5%, and the maximum error was less than 16%. The model that was established by the least square method had the highest accuracy; the average error of the multivariate nonlinear fitting of the four resistance characteristic prediction models was less than 4%, and the maximum error was less than 15%, which could be used to predict the resistance performance of the separator. The applicable working condition of the model is lubricating oil flow rate 4.3~8.5 L/min and oil-air ratio 0.5~3.

In order to study the separation characteristics of the aeroengine dynamic pressure oil-air separator, this paper uses the coupling method of PBM and CFD two-fluid model to study the influencing factors such as cylinder diameter, cylinder length, and other factors on the separator performance. The flow field structure, velocity, gas volume distribution, separation efficiency, and gas and liquid holdup rate in the separator under different operating conditions are analyzed. Combined with the analysis results of the cylinder diameter and the cylinder length, the influence law of length-diameter ratio on separation efficiency is summarized. The optimum length-to-diameter ratio that maximizes the separation performance of the separator is obtained in this research, which provides a reference for the design and improvement of the separator. The results show that, as the diameter of the cylinder increases, the separation efficiency increases first and then decreases. When dsep = 16 mm and dsep = 18 mm, the separator reaches its maximum efficiency, which is about 93%. With the increase of the cylinder length, the separation efficiency first increases and reaches the maximum when l2 = 90 mm and then decreases slowly. When the separator cylinder is either too long or too short, it will cause the separation performance to decrease. There is an optimal aspect ratio. There is an optimal aspect ratio, and the separation performance of the separator is the best when the aspect ratio is between 5 and 6.

Background/Aims: The ataxia-telangiectasia mutated (ATM) protein kinase is critical for the maintenance of genomic stability and acts as tumor suppressor. Although evidence shows that a DNA damage-independent ATM (oxidized ATM) may be involved in cancer progression, the underlying mechanism is still unclear. Methods: Immunohistochemistry, immunofluorescence and western blotting were applied to detect the levels of oxidized ATM. Transwell assay was used to detect the cell migration and invasion abilities in different treatments. Quantitative phosphoproteome analysis was performed using hypoxic BT549 cells, in the presence or absence of Ku60019, a specific inhibitor of ATM kinase. The phosphorylated cortactin, the target protein of oxidized ATM, was confirmed by immunoprecipitation-western blots and in vitro kinase assay. The functions of phosphorylated cortactin were studied by specific short hairpin RNA, site-directed mutation, transwell assay, and actin polymerization assay. Results: Enhanced oxidized ATM proteins were present not only in the advanced and invasive breast tumor tissues but also malignant hypoxic breast cancer cells, in the absence of DNA damage. Loss of ATM expression or inhibiting oxidized ATM kinase activity reduced breast cancer cell migration and invasion. Using quantitative phosphoproteomics approach, 333 oxidized ATM target proteins were identified, some of these proteins govern key signaling associated with gap junction, focal adhesion, actin cytoskeleton rearrangement. Cortactin, one of the biggest changed phospho-protein, is a novel oxidized ATM-dependent target in response to hypoxia. Mechanically, we reveal that hypoxia-activated ATM can enhance the binding affinity of cortactin with Arp2/3 complex by phosphorylating cortactin at serine 113, and as a result, in favor of breast cancer cell migration and invasion. Conclusion: Oxidized ATM can phosphorylate cortactin at serine 113, playing a critical role in promoting breast tumor cell mobility and invasion via actin polymerization.

Deep learning-based object detection in remote sensing images is an important yet challenging task due to a series of difficulties, such as complex geometry scene, dense target quantity, and large variant in object distributions and scales. Moreover, algorithm designers also have to make a trade-off between model’s complexity and accuracy to meet the real-world deployment requirements. To deal with these challenges, we proposed a lightweight YOLO-like object detector with the ability to detect objects in remote sensing images with high speed and high accuracy. The detector is constructed with efficient channel attention layers to improve the channel information sensitivity. Differential evolution was also developed to automatically find the optimal anchor configurations to address issue of large variant in object scales. Comprehensive experiment results show that the proposed network outperforms state-of-the-art lightweight models by 5.13% and 3.58% in accuracy on the RSOD and DIOR dataset, respectively. The deployed model on an NVIDIA Jetson Xavier NX embedded board can achieve a detection speed of 58 FPS with less than 10W power consumption, which makes the proposed detector very suitable for low-cost low-power remote sensing application scenarios.

Objective To explore the influence of impacted maxillary central incisor on craniofacial structure and its orthodontic treatment. Methods A total of 63 subjects with impacted upper central incisors were selected and categorized into the mixed (n=32) and permanent dentition group (n=31). By using the lateral cephalograms of each subject, 15 angular and 6 linear measurements were made. The cephalometric data were analyzed and compared to data of its corresponding control group with normal occlusion. Results Among the etiological factors of all 63 cases with impacted upper incisors, supernumerary teeth, dentigerous cyst or odontoma, mechanical trauma and idiopathic factors comprise of 6.3%, 6.3%, 12.4% and 73% respectively. Cephalometric analysis demonstrated a more retruded position of "A" point with decreased SNA and ANB angle in incisor impaction group. Dental compensations followed the decreased ANB angle with more proclined upper incisor and more upright lower incisor. In early stage of root development (stage 7 and 8 of Nolla's method), 12 out of 13 incisors were tracted successfully, whereas in late stage( stage 9 and 10), 7 out of 15 incisors were extracted. Conlusions Upper central incisor impaction adversely influences maxillary development. Early orthodontic treatment can improve successful rate and gain a better root morphology.

Background: Methionine adenosyl transferase II alpha (MAT2A) is the key enzyme to transform methionine into S-adenosylmethionine (SAM), the main methylgroup donor involved in the methylation. The purpose of our study wasto explore whether MAT2A-mediated methionine metabolism affected theexpression of inflammatory cytokines in human gingival fibroblasts(hGFs). Methods: Both healthy and inflamed human gingiva were collected. HGFs werecultured and treated with P. gingivalis, with or without MAT2Ainhibitor (PF9366), small interference RNA (siRNA), or extrinsic SAMpretreatment. The levels of inflammatory cytokines were detected byreal-time PCR, western blotting, and ELISA. SAM levels were detectedby ELISA. The nuclear factor-kappa B (NF-κB) and mitogen-activatedprotein kinase (MAPK) pathway was explored by western blotting. Results: The expression of MAT2A was increased in the inflamed tissues. P.gingivalis infection promoted the expression of MAT2A and SAM inhGFs. Meanwhile, PF9366 and MAT2A-knockdown significantly decreasedexpression of inflammatory cytokines and SAM production. PF9366inhibited activation of NF-κB/MAPK pathway in P. gingivalis-treatedhGFs. Conclusions: MAT2A-mediated methionine metabolism promoted P. gingivalis-inducedinflammation in hGFs. Targeting MAT2A may provide a novel therapeuticmethod for modulating periodontitis. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the accuracy of Ramfjord teeth (RT) protocol for the diagnosis of severe periodontitis based on different classifications and explore the misclassification bias such as teeth loss. Methods: Patients (n = 435) receiving full‐mouth periodontal examination (FMPE) were included. Patients were classified as severe (stage III/IV) periodontitis and no/mild/moderate (no/stage I/II) periodontitis according to the case definition proposed by the Centers for Disease Control and Prevention (CDC) and the American Academy of Periodontology (AAP)‐(CDC/AAP), a new classification introduced by AAP and the European Federation of Periodontology (EFP)‐(AAP/EFP), and consensus of Chinese experts (CCE). Sensitivity, specificity, positive predictive value, negative predictive value, Youden's index, and area under the receiver operating characteristic curve (AUROC) compared with FMPE were evaluated. Results: The specificity of RT was 86.8%, 92.2%, and 77.1% when compared with FMPE protocol based on CDC/AAP, AAP/EFP, and CCE classifications, while the AUROC value was 0.934, 0.961, and 0.886 specifically. The loss of the first molar leads to the greatest reduction in the detection rate of severe periodontitis. Conclusions: RT showed the highest specificity based on the new AAP/EFP classification. The loss of the first molar leads to the greatest reduction in the detection rate of severe periodontitis. [ABSTRACT FROM AUTHOR]