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Objectives: To investigate risk factors associated with occult lymph node metastases (ONM) and skip metastasis in early-stage oral tongue squamous cell carcinoma (OTSCC) patients. Meanwhile, to analyze the contribution of metastatic nodes to survival outcomes. Materials and methods: 544 OTSCC patients who were clinically staged T1-T2N0 with pathologic results from May 2018 to January 2024 were enrolled. Those with ONM were divided into subgroups with or without skip metastasis. Clinical, laboratorial, radiological and pathological factors between groups were analyzed by using univariate analysis and multivariate logistic analysis. The association of tumor growth behavior with the metastatic pattern of lymph nodes was summarized. Additionally, disease free survival (DFS) among different groups were compared using Kaplan-Meier analysis. Results: Tumor growth behavior was associated with ONM. Tumor thickness with a threshold of 6.4 mm was not inferior to histological depth of invasion in predicting ONM. Only 1.3% of patients had nodal involvement of neck level IV or V. The DFS of patients with ONM were significantly reduced than those without ONM (P < 0.001). The DFS between patients with and without skip metastasis exhibited no statistical significance(P = 0.246). The 1-year, 2-year recurrence rates of patients with or without ONM were 31.9%, 37.5%, 10.1% and 14.0%, correspondingly. Conclusions: Tumor thickness with a threshold of 6.4 mm could be used as a preoperative predictor for ONM. Elective neck dissection of level I - III might be sufficient for early stage OTSCC patients. OTSCC patients with ONM should be closely observed during the first 2 years after surgery. Clinical relevance: The risk of ONM in early stage OTSCC patients might be predicted by tumor thickness calculated on MR imaging. Elective neck dissection of level I – III could remove micrometastases timely and effectively. [ABSTRACT FROM AUTHOR]

With the increasing popularity of wearable electronic devices, there is an urgent demand to develop electronic textiles (e-textiles) for device fabrication. Nevertheless, the difficulty in reconciliation between conductivity and manufacturing costs hinders their large-scale practical applications. Herein, we reported a facile and economic method for preparing conductive e-textiles. Specifically, nonconductive polypropylene (PP) was wrapped by reduced graphene oxide (rGO), followed by the electrodeposition of Ni nanoparticles (NPs). Notably, modulating the sheet size of graphene oxide (GO) resulted in controllable deposition of Ni NPs with adjustable size, allowing for controlled manipulations over the structures, morphologies, and conductivity of the obtained e-textiles, which influenced their performance in electrochemical glucose detection subsequently. The optimal material, denoted as Ni/rGO0.2/PP, exhibited an impressive conductivity of 7.94 × 104 S·m−1. With regard to the excellent conductivity of the as-prepared e-textiles and the high electrocatalytic activity of Ni for glucose oxidation, the as-prepared e-textiles were subjected to glucose detection. It was worth emphasizing that the Ni/rGO0.2/PP-based electrode demonstrated promising performance for nonenzymatic/label-free glucose detection, with a detection limit of 0.36 µM and a linear response range of 0.5 µM to 1 mM. This study paves the way for further development and application prospects of conductive e-textiles. [ABSTRACT FROM AUTHOR]

In 2015, a full-scale ten-story reinforced concrete (RC) building structure was tested on the E-Defense shake table, the recorded test data from which provided a unique benchmark case to validate a state-of-the-art modeling approach. This paper presents the development and validation of a finite element model of the test building structure established on the OpenSees platform. In this model, RC beams and columns were simulated using the fiber-based beam-column element, and shear walls were modeled with the multi-layer shell element. The numerical model provided a reasonable estimate of the observed global responses of the test structure, including peak inter-story drifts and floor accelerations, for the wall direction. The multi-layer shell element effectively tracked the local strain, flexural and shear deformations of RC walls. Although the numerical model reasonably captured responses for the frame direction under base fixed JMA-Kobe 50% shaking, the simulation of RC frames was less accurate for base fixed JMA-Kobe 100% shaking when the test structure experienced significant damage at the maximum inter-story drift of 2.9%. Finally, a couple of important modeling issues for RC structure were discussed, including beam-column joint modeling and damping modeling. Use of the scissors model to represent the beam-column joints led to an improved estimation of the inter-story drifts of stories where the beam-to-column joints experienced severe damage. A transient Rayleigh damping model, in which a tangent stiffness matrix was used to formulate a system damping matrix, was recommended for structural nonlinear response history analysis. [ABSTRACT FROM AUTHOR]

This paper investigates an optimization problem corresponding to energy efficiency maximization of an unmanned aerial vehicle (UAV)-enabled relaying system, where a fixed-wing UAV acts as an amplify-and-forward mobile relay to assist data transmission between a source node and a destination node. On the premise of satisfying the speed and acceleration constraints of the UAV, the energy efficiency (EE) of the relaying system is maximized by jointly optimizing the UAV's trajectory and the individual transmit power levels of the source and the UAV relay. The initial joint optimization problem is non-convex and cannot be solved directly. Therefore, the joint optimization problem is decomposed into two sub-problems which are solved by applying the successive convex approximation technique and the Dinkelbach's algorithm. On this basis, an efficient iterative algorithm is proposed to tackle the joint optimization problem through the block coordinate descent technique. Simulation results demonstrated that by conducting the proposed algorithm, the flight trajectory of the UAV and the individual transmit power levels of the nodes can be flexibly adjusted according to the system conditions, and the proposed algorithm contributes to the higher EE compared with the benchmark schemes. [ABSTRACT FROM AUTHOR]

Conventional glassy carbon electrodes (GCE) cannot meet the requirements of future electrodes for wider use due to low conductivity, high cost, non-portability, and lack of flexibility. Therefore, cost-effective and wearable electrode enabling rapid and versatile molecule detection is becoming important, especially with the ever-increasing demand for health monitoring and point-of-care diagnosis. Graphene is considered as an ideal electrode due to its excellent physicochemical properties. Here, we prepare graphene film with ultra-high conductivity and customize the 3-electrode system via a facile and highly controllable laser engraving approach. Benefiting from the ultra-high conductivity (5.65 × 105 Sm−1), the 3-electrode system can be used as multifunctional electrode for direct detection of dopamine (DA) and enzyme-based detection of glucose without further metal deposition. The dynamic ranges from 1–200 µM to 0.5–8.0 mM were observed for DA and glucose, respectively, with a limit of detection (LOD) of 0.6 µM and 0.41 mM. Overall, the excellent target detection capability caused by the ultra-high conductivity and ease modification of graphene films, together with their superb mechanical properties and ease of mass-produced, provides clear potential not only for replacing GCE for various electrochemical studies but also for the development of portable and highperformance electrochemical wearable medical devices. [ABSTRACT FROM AUTHOR]

Bamboo has been used as a structural material for thousands of years. Due to its advantages in carbon absorption, mechanical properties, material supply and growth rate, etc., many bamboo products, especially engineered bamboo, were proposed and applied in buildings and structures. In this process, more than 40 years have passed since bamboo bolts were first applied. However, the shortage of strength and durability rendered the stagnated development of bamboo bolts, leading to the risk of being completely displaced. To arouse this environmental-friendly and high-specific-strength material in the application of ground anchorage, this paper summarised and further discussed the achievements of bamboo bolts and related products in China, including their classification, mechanical properties, anchorage performance, etc. According to the results, bamboo bolts still have vitality as a means of reinforcement if the shortcomings can be overcome. Therefore, a self-anchored bamboo bolt with a U-anchor head has been proposed in the following, which can give full play to the parallel-to-fibre tensile strength of bamboo strips and thus realise the efficient transformation from material properties to anchorage performance. [ABSTRACT FROM AUTHOR]

Slopes along the highway and railway routes are subjected to not only static loads but also dynamic loads generated by vehicles and trains. The induced excessive deformation potentially poses a threat to slope stability. In terms of the extensive application of ecological slope protection, plants play a critical role in slope stability, as the roots can enhance the shear strength of the soil. This study aims to investigate the influence of different root distribution patterns on the dynamic characteristics induced by cyclic loading. By conducting a group of dynamic triaxial tests, the results indicate that the root system can significantly enhance the liquefaction resistance of the soil when the soil is subjected to lower dynamic loads, and the cross arrangement has a better-reinforced effect than the mixed arrangement. The reinforced effect was not obvious when the soil was subjected to a dynamic load with a larger stress amplitude. In addition, based on the validation of the seed model, a new pore water pressure development model was proposed according to the test results. Overall, the research provides a new model and some innovative observations to better understand the dynamic behavior of root-reinforced soil. [ABSTRACT FROM AUTHOR]

With the increasing demand of consumers for diversified network services, more and more network service providers are competing fiercely in providing network composite services in order to meet the market demand. Network composition service is the most basic service. According to certain rules, it synthesizes new services and then realizes new functions. At present, the pricing of service composition by network service providers in the market is not scientific, meanwhile random and temporary pricing is still relatively common. In order to scientifically guide network service providers to price composite service scientifically and effectively, improve the profit of service providers, and meet the maximum service demand of consumers. Based on the theory of market demand price, this paper applies the pricing model in supply chain management to the pricing link of composite service network. From the perspective of network service providers, a two-objective competitive pricing model is constructed, and the simulation example analysis and sensitivity test are carried out. The simulation results show that the composite service provided by network service providers satisfy the general market demand price theory. In order to help service providers make scientific decisions on price adjustment of network services, this paper also makes sensitivity analysis of market demand on price changes. The research shows that the composite service provided by network service providers satisfy the general market demand price theory, while adjusting the price can only meet the general market demand price change theory if the original price is less than half of the original price. [ABSTRACT FROM AUTHOR]

Objectives: To establish and validate a predictive model integrating with clinical and dual-energy CT (DECT) variables for individual recurrence-free survival (RFS) prediction in early-stage glottic laryngeal cancer (EGLC) after larynx-preserving surgery. Methods: This retrospective study included 212 consecutive patients with EGLC who underwent DECT before larynx-preserving surgery between January 2015 and December 2018. Using Cox proportional hazard regression model to determine independent predictors for RFS and presented on a nomogram. The model's performance was assessed using Harrell's concordance index (C-index), time-dependent area under curve (TD-AUC) plot, and calibration curve. A risk stratification system was established using the nomogram with median scores of all cases to divide all patients into two prognostic groups. Results: Recurrence occurred in 39/212 (18.4%) cases. Normalized iodine concentration in arterial (NICAP) and venous phases (NICVP) were verified as significant predictors of RFS in multivariate Cox regression (hazard ratio [HR], 4.2; 95% confidence interval [CI]: 2.3, 7.7, p <.001 and HR, 3.0; 95% CI: 1.5, 5.9, p =.002, respectively). Nomogram based on clinical and DECT variables was better than did only clinical variables. The prediction model proved well-calibrated and had good discriminative ability in the training and validation samples. A risk stratification system was built that could effectively classify EGLC patients into two risk groups. Conclusions: DECT could provide independent RFS indicators in patients with EGLC, and the nomogram based on DECT and clinical variables was useful in predicting RFS at several time points. Key Points: • Dual-energy CT(DECT) variables can predict recurrence-free survival (RFS) after larynx-preserving surgery in patients with early-stage glottic laryngeal cancer (EGLC). • The model that integrates clinical and DECT variables predicted RFS better than did only clinical variables. • A risk stratification system based on the nomogram could effectively classify EGLC patients into two risk groups. [ABSTRACT FROM AUTHOR]

The multiplexed cancer cell line screening platform PRISM demonstrated its utility in testing hundreds of cell lines in a single run, possessing the potential to speed up anti-cancer drug discovery, validation and optimization. Here we described the development and implementation of a next-generation PRISM platform combining Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9-mediated gene editing, cell line DNA barcoding and next-generation sequencing to enable genetic and/or pharmacological assessment of target addiction in hundreds of cell lines simultaneously. Both compound and CRISPR-knockout PRISM screens well recapitulated the results from individual assays and showed high consistency with a public database. Xia et al. report the development and optimization of a high-throughput screening platform to systematically determine cancer cell sensitivity to pharmacological and genetic perturbations, BMS-PRISM, based on PRISM and high-throughput CRISPR/Cas9 loss-of-function screen technologies using cell line barcoding. [ABSTRACT FROM AUTHOR]

This paper addressed the energy-efficient resource management problem of an amplify-and-forward relay-assisted bidirectional relay system under a quality-of-service (QoS) constraint. The objective is to develop a holistic resource management algorithm for joint implementation of relay selection, power adaptation and bit-rate management for optimal energy efficiency (EE). A three-stage approach is proposed to solve the energy-efficient resource management problem. At stage 1 (stage of power management), a per-subcarrier energy-efficient problem is investigated, leading to a power adaptation algorithm for maximizing the system EE and ensuring the required level of the system QoS. Within the framework of the power adaptation algorithm and by exploiting spatial diversity of multiple-relay channels, distributed relay selection is investigated at stage 2 (stage of relay management). Next, the bit-rate management problem is tackled at stage 3, namely assigning bit rate to different subcarriers to maximize the system EE further. Finally, summarizing the results achieved at the three stages, a novel EE technology combined with relay selection, bit-rate management and power adaptation is developed. Simulation results validated the correctness and the efficiency of the proposed algorithm. It is shown that the proposed algorithm can significantly reduce the total transmit power of the system while ensuring the required system QoS. [ABSTRACT FROM AUTHOR]

In this paper, secrecy performance of a cognitive two-way denoise-and-forward relaying network consisting of two primary user (PT and PD) nodes, two secondary source (SA and SB) nodes, multiple secondary relay (SRi) nodes and an eavesdropper (E) node is considered, where SA and SB exchange their messages with the help of one of the relays using a two-way relaying scheme. The eavesdropper tries to wiretap the information transmitted between SA and SB. To improve secrecy performance of the network, two relay selection schemes called maximum sum rate and maximum secrecy capacity based relay selection (MSRRS and MSCRS) are proposed and analyzed in terms of intercept probability. It is proved that the MSRRS and MSCRS schemes have the same secrecy performance. Two parameters called average number gain and average cost gain are proposed to show the performance of the proposed relay selection schemes. Numerical results demonstrated that with 10 relay nodes, the proposed relay selection schemes can achieve, respectively, 3.7 dB and 1.9 dB’s improvements in terms of the reduced intercept probability and the enhanced secrecy capacity compared to the traditional round-robin scheme. [ABSTRACT FROM AUTHOR]

This paper addresses an optimal power adaptation (PA) problem of a two-time-slot bi-directional relaying network with a half-duplex amplify-and-forward relay. Unlike the existing studies, our goal is to develop effective PA strategies that can dynamically adjust the transmit-power levels of all the terminals to achieve energy efficiency, while satisfying the individual peak-power limit on each terminal and the quality-of-service (QoS) requirement of the network. By using the instantaneous channel state information (ICSI) and the statistical CSI (SCSI) knowledge, respectively, and with the aid of traffic information, the PA problem is analytically solved, leading to the so-called ICSI and SCSI based PA strategies with closed-form PA solutions for individual transmit-powers at the relay and the two end-terminals. Simulation results have verified the correctness of the derived expressions and confirmed the efficiency of our proposed strategies. It is shown that the proposed PA strategies can significantly reduce the total transmit-power of the network with guaranteed network QoS. [ABSTRACT FROM AUTHOR]

This paper studies a power minimization problem of an orthogonal frequency-division multiplexing modulated two-way amplify-and-forward relay wireless sensor network (WSN). The objective is to develop effective strategies for controlling the transmit power levels of WSN nodes and assigning the bit rates among different subcarriers to minimize the overall transmit power of the network, while ensuring the end-to-end target rates of the two WSN sources. By using channel knowledge at transmitters, a two-step method is proposed to solve the power minimization problem, resulting in a joint power control and bit rate assignment (JPCBRA) algorithm. At the first step, a per-subcarrier optimization problem concerning the power minimization issue is solved, giving closed-form solutions for individual transmit powers at the WSN sources and the relay. At the second step, the end-to-end target rates of the two WSN sources are allocated to different subcarriers so that the total transmit power can be reduced further while satisfying the initial data-rate requirement of the two WSN sources. Computer simulation results confirmed the effectiveness of the proposed JPCBRA algorithm. It is shown that with the JPCBRA algorithm, the total transmit power of the network can be significantly reduced in any traffic and/or channel cases in contrast to the compared schemes. [ABSTRACT FROM AUTHOR]

This study examines the design provisions of the Chinese GB 50011-2010 code for seismic design of buildings for the special boundary elements of T-shaped reinforced concrete walls and proposes an improved design method. Comparison of the design provisions of the GB 50011-2010 code and those of the American code ACI 318-14 indicates a possible deficiency in the T-shaped wall design provisions in GB 50011-2010. A case study of a typical T-shaped wall designed in accordance with GB 50011-2010 also indicates the insufficient extent of the boundary element at the non-flange end and overly conservative design of the flange end boundary element. Improved designs for special boundary elements of T-shaped walls are developed using a displacement-based method. The proposed design formulas produce a longer boundary element at the non-flange end and a shorter boundary element at the flange end, relative to those of the GB 50011-2010 provisions. Extensive numerical analysis indicates that T-shaped walls designed using the proposed formulas develop inelastic drift of 0.01 for both cases of the flange in compression and in tension. [ABSTRACT FROM AUTHOR]

Roots play an important role in stabilizing and strengthening soil. This article aims to study the mechanical properties of the interface between soil and roots with branches, using the pullout test method in the laboratory. The mechanical properties of the soil-root with branches interface is determined through the pullout-force and root-slippage curve (F-S curve). The results of investigating 24 Pinus tabulaeformis single roots and 55 P. tabulaeformis roots with branches demonstrated three kinds of pullout test failures: breakage failure on branching root, breakage failure on branching node, and pullout failure. The branch angle had a remarkable effect on the failure mode of the roots with branches: the maximum pullout force increased with the sum of the branch diameters and the branch angle. The peak slippage and the initial force had a positive correlation with the sum of the branch diameter. The significance test of correlation between branch angle and the initial force, however, showed they had no correlation. Branch angle and branch root diameter affect the anchorage properties between root system and soil. Therefore, it is important to investigate the anchorage mechanics of the roots with branches to understand the mechanism of root reinforcement and anchorage. [ABSTRACT FROM AUTHOR]

Scenario approach is a widely used tool in portfolio risk management, however, it often runs into dilemma when determining the distribution of asset returns with insufficient information, which will be used to simulate the scenarios. Also the quality of generated scenarios are not guaranteed even when the distribution of asset returns is known exactly. A set-valued scenario approach was proposed by Zhu, et al. (2015) as a possible remedy. As a necessary supplement of the results proposed by Zhu, et al. (2015), this paper theoretically investigates the convergent property of the numerical solution based on the set-valued scenario approach under the condition that the underlying distribution is known. [ABSTRACT FROM AUTHOR]

To study the seismic behavior of high strength concrete filled double-tube (CFDT) columns, each consisting of an external square steel tube and an internal circular steel tube, quasi-static tests on eight CFDT column specimens were conducted. The test variables included the width-to-thickness ratio ( β) and the area ratio ( β) of the square steel tube, the wall thickness of the circular steel tube, and the axial force (or the axial force ratio) applied to the CFDT columns. The test results indicate that for CFDT columns with a square steel tube with β of 50.1 and 24.5, local buckling of the specimen was found at a drift ratio of 1/150 and 1/50, respectively. The lateral force-displacement hysteretic loops of all specimens were plump and stable. Reducing the width-to-thickness ratio of the square steel tube, increasing its area ratio, or increasing the wall thickness of the internal circular steel tube, led to an increased flexural strength and deformation capacity of the specimens. Increasing the design value of the axial force ratio from 0.8 to 1.0 may increase the flexural strength of the specimens, while it may also decrease the ultimate deformation capacity of the specimen with β of 50.1. [ABSTRACT FROM AUTHOR]

The effect of freezing and thawing cycles on mechanical properties of concrete (compressive, splitting tensile strength) was experimentally investigated. According to the pullout test data of three kinds of deformed steel bars, the bond stress-slip curves after freezing and thawing were obtained. The empirical equations of peak bond strength were proposed that the damage accounted for effects of freezing and thawing cycle. Meanwhile, the mechanism of bond deterioration between steel bars and concrete after freezing and thawing cycles was discussed. All these conclusions will be useful to the durability design and reliability calculation of RC structures in cold region. [ABSTRACT FROM AUTHOR]

In order to detect the damage locations of complex spatial structures, a sensor region-based damage detection approach was developed based on the damage locating vectors method. A normalized damage locating index was introduced to identify the damage regions. An experiment on damage detection of a substructure model of the National Swimming Center ‘Water Cube’ was carried out. Two damage patterns were involved in the experiment. The test model was excited by using hammer impacts. Acceleration responses of the undamaged and damaged structure model were measured. Modal parameters were identified from the acceleration responses by utilizing the eigensystem realization algorithm (ERA). By using the developed sensor region-based method, the damage regions of the substructure model were located. The results show that the proposed method is able to effectively locate the damage regions. [ABSTRACT FROM AUTHOR]

Structure modal parameter online identification was used to monitor the structural health as evidenced by changes in the vibration characteristics. The natural excitation technique and the eigensystem realization algorithm were combined to identify the modal parameters in the time domain of a structure excited by simulated ambient vibrations. The mass-normalized mode shapes were obtained from the eigen-sensitivity analysis. The experimental modal analysis was performed on a two-story steel braced frame model excited by simulated ambient vibrations and hammer impacts. The mass-normalized mode shapes were acquired by changing the structural mass and by eigen-sensitivity analysis. From finite element analysis results and the experimental data, it is shown that this method is effective. [ABSTRACT FROM AUTHOR]

Inactivation of the E-cadherin cell adhesion molecule is believed critical in the development and behavior of many epithelial cancers, though mutations in the E-cadherin gene account for inactivation in only a fraction of cases. In many breast cancer lines, E-cadherin transcription is extinguished, but the role and significance of alterations in trans-acting transcription factors, promoter hypermethylation, and chromatin changes remain unresolved. To gain further insights into mechanisms underlying E-cadherin inactivation in breast cancer, we analysed somatic cell hybrids resulting from pairwise fusions between breast cancer lines with intact E-cadherin transcription (E-cad+) and lines lacking E-cadherin transcription (E-cad-). All hybrid lines failed to express E-cadherin transcripts and protein, despite the fact that E-cadherin alleles from E-cad+ lines were present in the hybrids. Elements in the proximal 108 bp of the E-cadherin promoter, when present in reporter gene constructs, were sufficient to direct strong transcription in E-cad+ breast lines, but displayed weak activity in E-cad- parental lines and hybrids. E-cadherin expression could not be restored in E-cad- lines or hybrids by treatment with a DNA demethylating agent and/or a histone deacetylase inhibitor. Our findings suggest loss of E-cadherin expression in some breast cancers may be due to dominant repression of the trans-acting pathways that regulate E-cadherin transcription. [ABSTRACT FROM AUTHOR]

Wireless capsule endoscope allows painless endoscopic imaging of the gastrointestinal track of humans. However, the whole procedure will generate a large number of capsule endoscopy images (CEIs) for reading and recognizing. In order to save the time and energy of physicians, computer-aided analysis methods are imperatively needed. Due to the influence of air bubble, illumination, and shooting angle, however, it is difficult to classify CEIs into healthy and diseased categories correctly for a conventional classification method. To this end, in the paper, a new feature extraction method is proposed based on color histogram, wavelet transform, and co-occurrence matrix. First, an improved color histogram is calculated in the HSV (hue, saturation, value) space. Meanwhile, by using the wavelet transform, the low-frequency parts of the CEIs are filtered out, and then, the characteristic values of the reconstructed CEIs' co-occurrence matrix are calculated. Next, by employing the proposed feature extraction method and the BPNN (back propagation neural network), a novel computer-aided classification algorithm is developed, where the feature values of color histogram and co-occurrence matrix are normalized as the inputs of the BPNN for training and classification. Experimental results show that the accuracy of the proposed algorithm is up to 99.12% which is much better than the compared conventional methods. [ABSTRACT FROM AUTHOR]