Abstract: Both pentachlorophenol and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) had been studied widely because of their probable anti-estrogenic activity. Sodium pentachlorophenol (PCP-Na), as a industrial product used in many fields, usually contains a trace of TCDD. The aim of this study was to assess the anti-estrogenic effect of PCP-Na in juvenile goldfish (Carassius auratus) hepatocyte cultures using vitellogenin (VTG) as the biomarker. The ID_{50} of PCP-Na was investigated and then a series of concentrations (0.001–0.5μg/ml) of PCP-Na were evaluated to estimate the anti-estrogenic activity. Results showed that PCP-Na was cytotoxic for hepatocytes even at very low concentration <1.21μg/ml, and it could not induce VTG…at any concentrations tested. Since it failed to stimulate VTG production, the possibility of its anti-estrogenic effect was tested, and a well-known anti-estrogenic compound-tamoxifen was used as positive control. PCP-Na caused a reduction in VTG synthesis in juvenile goldfish (Carassius auratus) hepatocytes at concentrations >0.1μg/ml when co-exposure with 1μg/ml 17β-estradiol (E2), making its anti-estrogenic activity approximately as potent as tamoxifen. Our results indicate that PCP-Na can act as negative modulators of estrogenic function in juvenile goldfish (Carassius auratus) hepatocytes.
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Abstract: This paper, probing into the present situation of urban domestic garbage by analyzing its growing trend, compositional change and regional difference, reveals the problems existing in its disposal and management in China. Meanwhile, a questionnaire was conducted in five big cities around China for surveying urban residents' attitudes towards garbage disposal and management policies and measures. Results showed the output of urban domestic garbage in Chinese cities is ever increasing, and the recoverable materials and energy in garbage composition are also increasing. The population growth, economic development, and increase of residents' expenditure level are the main factors influencing the growing…output and changing composition of the garbage. Information acquired from the questionnaire showed that majority of the urban residents are in favor of the garbage reduction policies and managerial measures and are willing to collaborate with municipal government in battling against garbage.Based on the analysis and questionnaire, some polieymaking-oriented suggestions such as operating the garbage disposal from a social welfare service to a sector of profit-gaining enterprises, transferring the garbage management from passive end control to active source control, promoting the classified garbage collection in cities around China, and charging garbage fees for its cleanup and disposal, have also been put forward in the paper.
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Abstract: With the development of China’s Internet, wireless network technology has been upgraded, and the rapid development of wireless network technology requires more advanced intelligent information processing technology to match. Therefore, based on the development of wireless network, this paper proposes intelligent tourism Management scheme. Firstly, the Wide & Deep Learning exploratory tourism route recommendation model was constructed. Then the Wide & DSSM exploratory recommendation algorithm combining the traditional recommendation algorithm with the depth model was proposed. Finally, the model and algorithm were tested through experiments. In this paper, the algorithm was used to study the semantic space vectors of both…the user dimension and the Travel line dimension, and the data of the user dimension was fully utilized, which brought a significant improvement to the performance of the recommended system.
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Keywords: Wireless network, intelligent tourism, recommendation, tour route
Abstract: American Water Works Association has estimated that, by 2050, the total cost of pipeline system management will exceed $1.7 trillion. Thus, it is important to assess the performance of water mains in order to optimize the rehabilitation process. Recently, the use of machine learning methods in pipeline condition prediction has increased. However, existing pipe performance prediction models rely solely on underlying data-generating distributions and do not accommodate different datasets. Hence, a stacking ensemble based method is proposed in this work to overcome the drawbacks of the existing models and improve the predictive power of this mode of analysis. Using soil…property data, both a single-model and an ensemble-model were constructed to forecast the pipe condition, and their prediction performance was compared and contrasted. Finally, the superiority of the proposed ensemble method was verified through its lowest value in the root-mean-square error relative to the individual models. The techniques presented in this work can aid in a reliable decision making in infrastructure management of buried pipeline networks.
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Abstract: Vehicular ad hoc networks (VANET) is seen as an effective solution to ensure the driving safety and efficiency. As a key foundation, the road side unit (RSU) connect with each other to form a backbone network in VANET. The authentication of RSUs is the main tasks to prevent the secure communication in VANET suffering from various attacks caused by cunning adversaries. In this paper, we propose a new type of verifiable secret sharing (VSS) scheme based on bivariate polynomial to achieving the RSU authentication in a secret sharing way. Our proposed VSS based authentication includes two phases. In phase 1,…the t RSUs that participate in secret reconstruction collaborate to detect whether there exist illegitimate ones; in phase 2, the t legitimate RSUs reveal their shares for secret reconstruction, and the fake shares can be identified. Our VSS facilitates the RSU authentication since (1) any RSUs participate in secret reconstruction can be confirmed legitimate, (2) any fake shares revealed in secret reconstruction can be identified, (3) a globalized group temporary session key will be established after the VSS process. In addition, our VSS scheme is unconditional secure since the security of our VSS is not based on any computational assumption.
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Keywords: Vehicular ad hoc networks, security, RSU authentication, verifiable secret sharing
Abstract: BACKGROUNDS: The purpose of this study was to investigate clinical role and functional effects of miR-431 expression in papillary thyroid carcinoma (PTC). METHODS: Expression of miR-431 in PTC patient tissue samples and plasma samples was examined by using qRT-PCR methods. Cell migration and invasion capacity were evaluated using transwell assays. Western blot analysis was performed to detect protein expression after miR-431 overexpression in PTC cells. RESULTS: We demonstrated that miR-431 expression was lower in PTC tissues and plasma samples compared to their corresponding controls. MiR-431 expression was particularly lower in PTC patients with lymph node (LN) metastasis. In vitro ,…miR-431 overexpression significantly inhibited cell migration, invasion and EMT process by upregulating E-cadherin and downregulating Vimentin expression. Additionally, wedemonstrated that miR-431 overexpression suppressed Hedgehog (Hh) signaling pathway by downregulating Gli1 expression. CONCLUSION: Our results indicated that miR-431 could serve as a predictor for PTC patients with positive lymph node metastasis and a potential target of PTC treatment.
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Abstract: This paper presents a Radial Basis Function (RBF) and Finite Element Method (FEM) hybrid approach to solve a 3-D electromagnetic problem. The proposed method divides the entire computational domain into a series of sub-domains. The shape functions of each sub-domain are obtained by point interpolation method based on RBF to improve fitting performance of FEM. Each sub-domain consists of Galerkin FEM elements in the entire computational domain. To validate the proposed method, a case study is carried out based on a dual-electrode DC arc furnace. The results demonstrate that RBF and FEM hybrid approach in this paper is superior to…the traditional FEM.
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Keywords: Finite element method, radial basis function, magnetic vector potential, three dimensional (3-D)
Abstract: This paper examines with statistical analysis of transient response for typical vehicle mounted antenna - monopole on conductive plane varying multiple random field parameter distributions of high-altitude electromagnetic pulse (HEMP) by employing the combinations of Method of Moment (MoM) method and a high computational efficiency statistical analysis tool called polynomial chaos expansion method (PCEM).The main procedures of the combination method are composed of two following steps: Firstly, the frequency-domain transfer function of the antenna port response for the monopole is derived by using MoM and then the transient current response is obtained with inverse Fourier transform; Secondly, the statistical model…with multiple random input parameters are calculated by PCEM according to the transient response data. The statistical indicators of the model concentrate on the confidence interval of the transient response, the Probability Density Function (PDF) and Cumulative Probability Density Function (CDF) of the current peak. The paper not only focuses on the random radiated field parameter such as elevation, azimuthal angle, polarization angle and magnetic dip angle but also considers height of burst, ratios of plane length versus antenna height, and antenna down-tilt angles. The analysis results demonstrate the validation of the proposed statistical method and provide the reference base for system HEMP survivability evaluation and protection design.
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Abstract: To provide a scientific basis for the resource utilization of chromium slag, this article studies the release law of hexavalent chromium in the aged calcium-free chromium slag. XRD (X-ray diffractometer) and MLA (Mineral Liberation Analyzer) were used to analyze the composition of the chromium slag; using sulfuric acid-nitric acid as the leaching solution, the release law of hexavalent chromium in chromium slag and the leaching kinetics were studied. The results show that main components of the chromium slag are magnesioferrite, chromite, hematite, hydrargillite, and spinel; chromium is mainly present in chromite and magnesioferrite; the leaching rate of hexavalent chromium increases…with the increase of temperature or the decrease of pH. The analysis of leaching kinetics shows the leaching rate is controlled by the internal diffusion reaction, and the apparent activation energy is 11.93 kJ·mol–1 . The chromium slag is aged in high temperature seasons, which is conducive to the precipitation of hexavalent chromium in the chromium slag, can increase the yield of chromate in the roasting kiln, and is conducive to resource utilization; chromium slag should be stored in order to prevent acid rain erosion which leads to environmental pollution risk (e.g. drinking water).
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Abstract: BACKGROUND: Ureteral stents are commonly used in urology. However, complications such as encrustation and infection on the surface of the stent, and injury to the ureteral mucosa can occur after implantation, causing discomfort for patients. OBJECTIVE: We intend to confirm the biosafety of polyvinylpyrrolidone (PVP) hydrophilic coating and its lubrication properties for surface modification of ureteral stents to reduce friction and improve patient comfort. METHODS: Based on our previous studies, we have developed a PVP hydrophilic coating for surface modification of ureteral stents. We firstly investigated the cytotoxicity, intradermal irritation, delayed type hypersensitivity, and acute systemic reactions of stent coating…extracts. We further characterized the break strength, retention strength, and dynamic friction of the stent. RESULTS: The cell survival rate of all experimental groups was greater than 70%. No hypersensitivity reaction, systemic toxicity reaction, or obvious intradermal reaction were observed. The above results indicate that the test results of the modified stent meet the requirements of ISO 10993-5: 2009 (Cytotoxicity); ISO 10993-10:2021 (Sensitization and Irritation); ISO 10993-11:2017 (Acute Systemic Toxicity). After soaking in artificial urine for an extended period, there was no obvious change in its super-slip performance. CONCLUSION: Our results confirm the safety and lubrication characteristics of PVP hydrophilic coating for ureteral stent surface modification. The performance of this coating has the potential to reduce complications after stent implantation, thereby improving patient comfort, reducing medical burden, and has a good clinical application prospect.
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