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Reliability updating refers to a problem that integrates Bayesian updating technique with structural reliability analysis and cannot be directly solved by structural reliability methods (SRMs) when it involves equality information. The state-of-the-art approaches transform equality information into inequality information by introducing an auxiliary standard normal parameter. These methods, however, encounter the loss of computational efficiency due to the difficulty in finding the maximum of the likelihood function, the large coefficient of variation (COV) associated with the posterior failure probability and the inapplicability to dynamic updating problems where new information is constantly available. To overcome these limitations, this paper proposes an innovative method called RU-SAIS (reliability updating using sequential adaptive importance sampling), which combines elements of sequential importance sampling and K-means clustering to construct a series of important sampling densities (ISDs) using Gaussian mixture. The last ISD of the sequence is further adaptively modified through application of the cross entropy method. The performance of RU-SAIS is demonstrated by three examples. Results show that RU-SAIS achieves a more accurate and robust estimator of the posterior failure probability than the existing methods such as subset simulation., 38 pages, 6 tables, 9 figures

Reliability of concrete that are exposed to marine environment can be substantially threatened by chloride and carbonation-induced corrosion of reinforced concrete. The metric of reliability quantifies this risk in the form of reliability or probability of occurrence. Moreover, environmental observations such as long-term structural health data and testing specimen in exposed station can be leveraged to improve the updating accuracy, which facilitate strategic decision-making for structural inspection, maintenance, and rehabilitation. However, due to the complexity of physical models, the computational process can be also challenging. To overcome this limitation, RUAK (Reliability Updating with Adaptive Kriging) has been proposed to incorporate the adaptive Kriging within the reliability updating framework. Therefore, this paper explores the reliability analysis of a chloride erosion example with RUAK.

Traditional cancer therapeutics have been criticized due to various adverse effects and insufficient damage to targeted tumors. The breakthrough of nanoparticles provides a novel approach for upgrading traditional treatments and diagnosis. Actually, nanoparticles can not only solve the shortcomings of traditional cancer diagnosis and treatment, but also create brand-new perspectives and cutting-edge devices for tumor diagnosis and treatment. However, most of the research about nanoparticles stays in vivo and in vitro stage, and only few clinical researches about nanoparticles have been reported. In this review, we first summarize the current applications of nanoparticles in cancer diagnosis and treatment. After that, we propose the challenges that hinder the clinical applications of NPs and provide feasible solutions in combination with the updated literature in the last two years. At the end, we will provide our opinions on the future developments of NPs in tumor diagnosis and treatment.

Physical models for carbonation-induced reinforcement corrosion and concrete cracking have been proposed mainly based on accelerated carbonation tests. However, it has been criticised for not being...

The concept of seismic resilience has received significant attention from academia and industry during the last two decades. Different frameworks have been proposed for seismic resilience assessment of engineering systems at different scales (e.g., buildings, bridges, communities, and cities). Testbeds including Centerville virtual community (CVC), Memphis testbed (MTB), and the virtual city of Turin, Italy (VC-TI) have been developed during the last decade. However, the resilience assessment results of Chinese cities still require calibration based on a unified evaluation model. Therefore, a geographic information system (GIS)-based benchmark model of a medium-sized city located in the southeastern coastal region of China was developed. The benchmark city can be used to compare existing assessment frameworks and calibrate the assessment results. The demographics, site conditions, and potential hazard exposure of the benchmark city, as well as land use and building inventory are described in this paper. Data of lifeline systems are provided, including power, transportation, water, drainage, and natural gas distribution networks, as well as the locations of hospitals, emergency shelters, and schools. Data from past earthquakes and the literature were obtained to develop seismic fragility models, consequence models, and recovery models, which can be used as basic data or calibration data in the resilience assessment process. To demonstrate the completeness of the data included in the benchmark city, a case study on the accessibility of emergency rescue after earthquakes was conducted, and the preliminary results were discussed. The ultimate goal of this benchmark city is to provide a platform for calibrating resilience assessment results and to facilitate the development of resilient cities in China.

Increasing evidences suggest that insufficient radiofrequency ablation (IRFA) can paradoxically promote tumor invasion and metastatic processes, whereas the effects of moderate hyperthermia on cancer progression are not well illustrated. Our study found that IRFA can increase the in vitro migration, invasion, and epithelial–mesenchymal transition (EMT) of hepatocellular carcinoma (HCC) cells via induction of Snail, a master regulator of EMT events. Among measured miRNAs, IRFA can decrease the expression of miR-148a-5p in HCC cells. Whereas overexpression of miR-148a-5p can reverse IRFA-induced migration of HCC cells and upregulation of Snail, mechanistically overexpression of miR-148a-5p can directly target and decrease the expression of protein kinase ATM (ataxia telangiectasia mutated), which can increase protein stability of Snail. Collectively, our data suggest that IRFA can regulate the miR-148a-5p/ATM/Snail axis to trigger migration of HCC cells.

The maturity of structural health monitoring technology brings ever-increasing opportunities for geotechnical structures and underground infrastructure systems to track the risk of structural failure, such as settlement-induced building damage, based on the monitored data. Reliability updating techniques can offer solutions to estimate the probability of failing to meet a prescribed objective using various types of information that are inclusive of equality and inequality. However, the update in reliability can be highly sensitive to monitoring location. Therefore, there may exist optimal locations in a system for monitoring that yield the maximum value for reliability updating. This paper proposes a computational framework for optimal monitoring location based on an innovative metric called sensitivity of information (SOI) that quantifies the relative change in unconditional and conditional reliability indexes. A state-of-the-practice case of risks posed by tunneling-induced settlement to buildings is explored in-depth to demonstrate and evaluate the computational efficiency of the proposed framework.

Many historic wood building areas are susceptible to fire hazards. The location of fire stations shall be carefully selected to provide adequate fire protection. In this study, an innovative procedure to determine optimal fire station locations is proposed considering the unique fire development pattern from different possible fire origins and the potential loss from both daily fires and post-earthquake fires (PEF). The fire spread processes originated from different buildings are firstly simulated using a physics-based fire spread analysis; and then different optimization objectives are selected to reflect the decision makers’ attitudes towards the two fire risks. A non-dominated sorting genetic algorithm (NSGA-II) is adopted to obtain the Pareto-optimal solutions, i.e., the locations of fire stations corresponding to the minimum average burnt loss for daily fire, and the minimum probability of exceeding an acceptable fire loss from PEF, respectively. The approach is applied to an ancient town in Southwest China for illustration. The proposed method can reduce the fire loss by 5% on average compared with the traditional max covering location method, and the impacts of uncertainties in the estimate of time for fire brigade to arrive and the change of unacceptable fire loss on the optimal locations of fire stations are discussed.

BackgroundLung adenocarcinoma (LUAD) is one of the most common malignancies with a rise in new cases worldwide each year. Recurrence significantly influences the survival in patients with LUAD. Yin-Huo-Tang (YHT) is a classic traditional Chinese prescription, used to prevent lung cancer relapse by “nourishing yin and clearing heat”. MethodsIn this study, the mechanism of YHT in LUAD recurrence was investigated. Firstly, the bioactive compounds-targets network and the protein–protein interaction network were constructed, and functional annotation and pathway enrichment analyses were performed. Pivotal compounds and hub genes were selected from the networks. Subsequently, the effectiveness of YHT was confirmed in lewis lung carcinoma mice. RNA sequencing was used to explore the mRNA expression differences between tumor tissues in the model mouses and YHT-treated mouses. The pathways screened by network pharmacology and RNA sequencing analysis at the same time were considered the most important pathways. At last, qualitative phytochemical analysis, molecular docking technology, PCR and WB analysis were used to validate the pivotal active ingredients, hub genes and main pathways.ResultsThere were 128 active compounds, 419 targets interacting with LUAD recurrence. Network analysis identified 4 pivotal compounds, 28 hub genes and 30 main pathways. Target genes mainly focused on inflammation, metabolism, immune responses and apoptosis. We confirmed that YHT could inhibit the recurrence of lung adenocarcinoma through animal experimental study. Sphingolipid signaling pathway was the common main pathway in network pharmacology and RNA sequencing results. The hub genes related with the sphingolipid signaling pathway was S1PR5. Qualitative phytochemical analysis of the water extract of YHT confirmed the presence of 3 pivotal compounds, namely stigmasterol, nootkatone and ergotamine. The results of molecular docking verified the pivotal compounds of YHT could good affinity with the S1PR5. The PCR and WB analysis verified YHT suppressed lewis lung cancer cells proliferation by inhibiting S1P/S1PR5/Gi/Ras/Raf/MEK/ERK pathway, and inhibited migration through S1P/S1PR5/Gi/PI3K/RAC pathway.Conclusion The results confirmed the therapeutic effect of YHT on the recurrence of LUAD by multi-component-multi-target mode, the sphingolipid signaling pathway was one of the most relevant potential signaling pathways.

Surface transportation systems are an essential part of urban transportation infrastructure and are susceptible to damage from earthquakes. This damage, along with the lack of prior warning of eart...

Reliability-based quantitative durability design approach has been developed for reinforced concrete structure with long service life and under brutal chloride-aggressive condition. However, there is few discussions on the design of conformity control scheme for durability parameters. The gap may result in some inappropriate acceptance criteria, and thus insufficient reliability of the constructed structure or the unnecessary rework due to the conservatism of conformity control scheme. For the construction of Hong Kong–Zhuhai–Macau project, this paper establishes the acceptance sampling plan for chloride diffusivity of concrete. Firstly the probabilistic relationship between the diffusion coefficient for durability design (DNSSD) and that for quality control (DNSSM) is created, then the acceptance quality level and the limiting quality level are determined based on the reliability-based durability design equation, and finally the acceptance criteria for DNSSM is established by balancing the consumer’s risk and the producer’s risk. Discussion is made to examine the improvement in structural durability due to the conformity control. It is found that the sample size is important for controlling the producer’s risk. Furthermore, the bivariate control scheme is also established, which may help to reduce producer’s risk without aggravating consumer’s risk.

IntroductionNational Comprehensive Cancer Network has recommended cryoablation to replace the resection in the treatment of medically operable non-small cell lung cancer (NSCLC). Cryoablation also has been used for the advanced NSCLC in randomised controlled trials. However, they have not been systematically reviewed. Here, we provide a protocol to evaluate the effectiveness and safety of cryoablation in the treatment of advanced NSCLC.Methods and analysesWe will search PubMed, Embase, the Cochrane Library, Chinese Biomedical Database, China National Knowledge Infrastructure, Wanfang Database and Chinese Scientific Journal Database without language restrictions from inception until 1 February 2020. Trial registers (International Clinical Trials Registry platform, the US National Institutes of Health Ongoing Trials Register and the ISRCTN registry) and reference lists of retrieved articles will also be searched. Two reviewers will independently extract data on participants, interventions, comparisons, outcomes and assess the methodological quality by the Cochrane risk of bias tool. The strength of evidences will be evaluated according to the Grading of Recommendations Assessment, Development and Evaluation approach. Review Manager V.5.3 software will be used for data analyses. Meta-analyses will be performed if the data are sufficiently homogeneous. The primary outcomes will be objective response rate and overall survival. The secondary outcomes will be adverse effects, health-related quality of life, changes of immune indicators and surrogate outcomes (disease control rate, progression-free survival and survival rate).Ethics and disseminationEthics approval is not required, as this study will not involve patients. The results of this study will be submitted to a peer-reviewed journal for publication, to inform both clinical practice and further research.PROSPERO registration numberCRD42019138660.

Irinotecan (CPT11) is one of the most effective drugs for treating colon cancer, but its severe side effects limit its application. Recently, a traditional Chinese herbal preparation, named PHY906, has been proved to be effective for improving therapeutic effect and reducing side effects of CPT11. The aim of the present study was to provide novel insight to understand the molecular mechanism underlying PHY906-CPT11 intervention of colon cancer. Based on the GSE25192 dataset, for different three treatments (PHY906, CPT11, and PHY906-CPT11), we screened out differentially expressed genes (DEGs) and constructed a co-expression network by weighted gene co-expression network analysis (WGCNA) to identify hub genes. The key genes of the three treatments were obtained by merging the DEGs and hub genes. For the PHY906-CPT11 treatment, a total of 18 key genes including Eif4e, Prr15, Anxa2, Ddx5, Tardbp, Skint5, Prss12 and Hnrnpa3, were identified. The results of functional enrichment analysis indicated that the key genes associated with PHY906-CPT11 treatment were mainly enriched in ‘superoxide anion generation’ and ‘complement and coagulation cascades’. Finally, we validated the key genes by Gene Expression Profiling Interactive Analysis (GEPIA) and RT-PCR analysis, the results indicated that EIF4E, PRR15, ANXA2, HNRNPA3, NCF1, C3AR1, PFDN2, RGS10, GNG11, and TMSB4X might play an important role in the treatment of colon cancer with PHY906-CPT11. In conclusion, a total of 18 key genes were identified in the present study. These genes showed strong correlation with PHY906-CPT11 treatment in colon cancer, which may help elucidate the underlying molecular mechanism of PHY906-CPT11 treatment in colon cancer.

Background This study compared a co‐ablation (CA) system, which is a novel ablation device, with an argon‐helium cryoablation (AHC) system. We aimed to compare the efficacy and safety of CA and AHC for the treatment of stage III–IV non‐small cell lung cancer (NSCLC). Methods We conducted a multicenter randomized controlled trial (RCT) to determine whether CA was noninferior to AHC. The primary efficacy endpoints were the iceball coverage rate (ICR) and the disease control rate (DCR) one month after treatment. Noninferiority was declared if the lower limit of two‐sided 95% confidence interval (CI) was less than 10%. The ICR and DCR were identified by logistic regression. Treatment safety was assessed. Results A total of 81 patients underwent randomization (41 assigned to the CA and 40 assigned to the AHC groups)and transthoracic ablation. The ICRs in the CA and AHC groups were 99.24% ± 2.18% and 98.66% ± 3.79%, respectively. Central lesions were associated with an increased risk of an incomplete ICR. The DCRs in the CA and AHC groups were 97.6% and 95%, respectively. A smaller lesion area in the CA group was significantly correlated with a better DCR. The rate of complications was 29.26% in the CA group and 30% in the AHC group. (P = 0.943). There was less probe usage per patient in the CA group. Conclusions We determined that CA is noninferior to AHC in terms of efficacy and safety for the treatment of stage III–IV NSCLC. A smaller lesion area in the CA group was significantly correlated with a better DCR. Key points CA was noninferior to AHC for stage III–IV NSCLC., Co‐ablation (CA) is noninferior to argon‐helium cryoablation (AHC) in terms of efficacy and safety for the treatment of stage III–IV NSCLC. A smaller lesion area in the CA group was significantly correlated with a better disease control rate (DCR).

This paper reviews the fundamentals of the durability of structural concrete, and then applies the concepts to the durability design, quality control, performance assessment and maintenance planning of concrete structures in Hong Kong-Zhuhai-Macau (HZM) sea link project with design working life of 120 years. The durability design adopts a multi-level philosophy for different durability risks and uses model-based approach to determine design parameters. The long-term exposure data of 30 years were used to calibrate the chloride ingress model and quantify the modelling uncertainty. The durability quality control was realized through converting the design values to laboratory characterization values, especially for the chloride diffusivity. With the data collected in construction phase, a full-probabilistic assessment is performed on the achieved performance against the chloride ingress, serving as basis for maintenance planning. The open issues related to the durability of concrete infrastructures with long service life are elaborated in the end.

Electric power systems play a critical role in assuring modern society’s functionalities. Earthquakes are one of the most destructive natural hazards that affect the serviceability of electricity t...

Resilience is an attribute of communities, and is supported by community building sectors (occupancy types) with different functionalities. Evaluating community resilience and functionality requires the establishment of new metrics and their quantification. This study introduces a methodology to consider how the interdependencies in functionality among different building sectors impact community resilience. Four building sectors that provide essential functions to a community, i.e. housing, education, business and public services, are considered. The percentage of people in a community who dislocate following a disaster as a result of the physical damages to buildings is selected as the resilience metric in this conceptual study. A framework is further developed to determine the optimum strategies for retrofitting community building portfolios as a whole in order to achieve an overall community resilience objective expressed in terms of the threshold value of the community resilience metric identified above. Finally, the methodology to quantify community functionality and the associated retrofit optimization algorithm are illustrated using a simplified hypothetical community building portfolio in China exposed to potentially severe earthquakes, in which the objective is to achieve a predetermined functionality level when financial constraints may be present.

Civil structures and infrastructure facilities are susceptible to deterioration posed by the effects of natural hazards and aggressive environmental conditions. These factors may increase the risk of service interruption of infrastructures, and should be taken into account when assessing the structural reliability during an infrastructure's service life. Modeling the resistance deterioration process reasonably is the basis for structural reliability analysis. In this paper, a novel model is developed for describing the deterioration of aging structures. The deterioration is a combination of two stochastic processes: the gradual deterioration posed by environmental effects and the shock deterioration caused by severe load attacks. The dependency of the deterioration magnitude on the load intensity is considered. The Gaussian copula function is employed to help construct the joint distribution of correlated random variables. Semi-analytical methods are developed to assess the structural failure time and the number of significant load events (shocks) to failure. Illustrative examples are presented to demonstrate the applicability of the proposed model in structural reliability analysis. Parametric studies are performed to investigate the role of deterioration-load correlation in structural reliability.

Understanding the spatial structure of wind speed profile of a tropical cyclone (TC) is of critical importance to assess the TC-related damage and map the risk for afflicted areas. The wind field structure of a TC can be regarded as a horizontal primary circulation superimposed by a vertical–radial secondary convection driven by thermal balance. The gradient wind field model has been widely utilized in literature to describe the radial distribution of wind speed with respect to the TC center. In this paper, a new gradient wind field model is developed for translating TCs, based on the vector summation of the rotational wind speed and the translation speed. The accuracy and efficiency of the proposed model are demonstrated through comparing the wind fields generated from model solution and those recorded historically. The proposed model only involves simple algebra, which is beneficial for practical applications, especially in simulation-based studies of TC wind field modeling.

Purpose There are two kinds of thawing temperatures commonly adopted in cancer cryosurgery. We attempted to compare their efficacy differences in this study to optimize the surgical method. Method Forty-five C57BL/6 J mice with GFP-labeled Lewis lung cancer were randomized into three groups ( n = 15 for each): control group, T0 group (thawing temperature 0 °C), and T40 group (thawing temperature 40 °C). Cryoablation was performed using a combined surgical system. When the ice ball reached the border of the tumor, they were rewarmed to 0 °C and 40 °C, respectively, using a single freeze–thaw cycle. After the surgery, weight of these mice, length/width and the fluorescence intensity (FI) of the tumors were recorded. All mice were sacrificed on Day 14 after the procedures and their xenografts were excised and weighed immediately. We also checked for pulmonary metastasis, and examined tumor specimens using HE staining. Results Body weights, tumor volumes and FI in the three groups did not differ significantly at baseline. On Day 14, 39% of the tumors in the T0 group decreased in volume, whereas only 17% in the T40 group did. The average FI in the control group increased by 60%, but declined by 72% in T0 mice and 69% in T40 mice. Tumor inhibition rates were 71.64% in the T0 group and 68.12% in the T40 group. Lung metastases rates and histological changes were compatible between the two intervention groups. Conclusion Using 0 °C as the thawing temperature may have more potential benefits in cryoablation efficacy.

The quality of precast concrete (PC) component connections is one of the main factors that affect the seismic reliability of PC structures. China is developing PC structures in high seismic regions, and it is important to assess the effect of connection deficiency on seismic performance of PC structures. This paper presents a comprehensive method to assess the seismic reliability of PC shear wall-frame structure whose wall panels are assembled through grouted sleeve connections which are susceptible to insufficient grouting. Considering the uncertainties associated with the number, locations and loading behavior of defected sleeve connections, the probabilistic behavior of PC shear wall with defected connections is estimated through point estimate method using simulation results of the experiment-validated finite element model. Then, a simple shear wall-frame building, designed for the seismic intensity of 8 according to China’s seismic design code, is modeled on platform of OpenSees. Static pushover analyses and seismic fragility analyses are performed on the structure with different degrees of connection deficiency, to investigate the effect of deficiency occurrence rate on seismic performance. The seismic performance is significantly affected by connection deficiencies; it no longer meets the requirement of seismic design as the deficiency occurrence rate exceeds 25%, so the occurrence rate of defected connections should be controlled carefully in construction site.

Probabilistic damage evaluation and loss estimation of spatially distributed infrastructure systems (e.g. an electric power system or a building portfolio) under a scenario tropical cyclone must consider the spatial correlation of cyclone wind speeds to estimate their impact on the built environment statistically. Previous studies have seldom considered the impact of this spatial correlation on damage assessments of distributed civil infrastructure. In this paper, a stochastic field model is developed to capture the uncertainty of cyclone wind speeds and their spatial correlation for the North Atlantic region. A series of recorded wind speed fields of historical cyclone events are examined. The bias values between the recorded wind speeds and computed wind speeds based on a widely used cyclonic wind field model are obtained. The statistics of the wind field bias are estimated using geostatistical tools. The effect of wind speed uncertainty and spatial correlation on performance assessment of distributed infrastructure systems is illustrated using an electric power system, where the metrics of performance are damage ratio, outage ratio and outage cost.

Civil infrastructure systems provide physical supports to a community’s functionalities and are expected to achieve acceptable safety levels subjected to extreme load effects. However, these systems may deteriorate with time as a result of aggressive environmental or operating conditions in service, implying that the system reliability may decline beyond the baseline as assumed for design. Moreover, the increasing trend of the external loads may also contribute to the reduction of the system reliability. In this paper, a semi-analytical method is proposed for assessing the reliability of aging systems subjected to non-stationary loads. The series system is considered, where the system failure is defined as the failure of any single component (structure) among the system. The application of the proposed method is illustrated using a representative series bridge network with several individual bridges. The role of parameters such as the variations in the load intensity, resistance correlation and number of ...

Life cycle cost (LCC) analysis offered a useful framework to think about the efficiency of infrastructures investment. However, the widely accepted algorithm of the LCC doesn’t account for the decision maker's attitude toward the risk of future consequences. The cumulative prospect theory (CPT) can be used to reveal the decision maker's preference under different risk and uncertainty conditions, and has been applied in literature to some design optimization issues. Nevertheless, previous research didn’t consider the fact that people's risk preference may vary with time, i.e., there is a reasonable tendency that people will be more risk-averse to the near future losses than to the far future losses. Recognizing this, this paper adopts the CPT model in the minimum expected cost analysis, and moreover incorporates the time-varying weighting function included in the CPT model to reflect the possible changing of risk preference toward future events. A seismic retrofit optimization of a dam built in strong earthquake-prone area is used to demonstrate the application of the method, and it is found that considering the time-varying of risk preference leads to a low design level compared with that by the CPT model, but a high design level compared with the traditional LCC.

Natural hazards such as hurricanes may cause extensive economic losses and social disruption for civil structures and infrastructures in coastal areas, implying the importance of understanding the construction performance subjected to hurricanes and assessing the hurricane damages properly. The intensity and frequency of hurricanes have been reported to change with time due to the potential impact of climate change. In this paper, a probability-based model of hurricane damage assessment for coastal constructions is proposed taking into account the non-stationarity in hurricane intensity and frequency. The non-homogeneous Poisson process is employed to model the non-stationarity in hurricane occurrence while the non-stationarity in hurricane intensity is reflected by the time-variant statistical parameters (e.g., mean value and/or standard deviation), with which the mean value and variation of the cumulative hurricane damage are evaluated explicitly. The Miami-Dade County, Florida, USA, is chosen to illustrate the hurricane damage assessment method proposed in this paper. The role of non-stationarity in hurricane intensity and occurrence rate due to climate change in hurricane damage is investigated using some representative changing patterns of hurricane parameters.

Probability-based assessment of hurricane damage costs for coastal communities is vital for policy-makers and insurers. The uncertainties associated with hurricane damage costs include both the inherent uncertainty due to the random nature of hurricane process and the model uncertainty of the mathematical representation of hurricane damage (vulnerability model). The hurricane vulnerability model has traditionally been modeled as a deterministic function of hurricane wind speed in the literature, without considering the effect of vulnerability model uncertainty on hurricane damage assessment. This paper develops two methods to assess the hurricane damage costs in the presence of vulnerability model uncertainty. To account for the non-stationarity in hurricane actions due to the potential impact of climate change, the hurricane occurrence process is modeled as a non-stationary Poisson process and the hurricane intensity is assumed to vary in time with time-variant statistical parameters of hurricane wind speed. A case study of Miami-Dade County, Florida, is conducted to illustrate the proposed methods and to investigate the impact of vulnerability model uncertainty on hurricane damage costs.

Objective This intervention has been shown to be clinically efficacious and safe. The aim of this study was to determine the effect of different intervention times on the efficacy of gastroparesis external application prescription versus placebo for the treatment of gastrointestinal tumor postoperative, postsurgical gastroparesis. Methods A multicenter, randomized, double-blind, placebo controlled phase III clinical trial was designed to demonstrate superiority and conducted at four grade 3A hospitals in Beijing. Patients diagnosed with gastrointestinal tumor postsurgical gastroparesis and local cold syndrome in the abdomen were enrolled and received conventional treatment (nutritional support, gastrointestinal decompression, and prokinetic medication). Treatment and control groups respectively received gastroparesis external application prescription or placebo acupoint application over a treatment course of 14 days or until the primary efficacy endpoint (clinical efficiency) was achieved. Results A total of 120 patients were enrolled in the treatment and control groups ( n = 60 per group), and 15 patients dropped out of the study because of skin allergies ( n = 7) or poor efficacy ( n = 8). The efficacy among patients in Class B of Group A(treatment group) was marginally better than that of Group B (control group) (64.28% vs. 55.56%) although the difference between the two groups was not significant. However, the efficacy among patients in Class C of Group A was significantly better than that of Group B (79.49% vs. 43.33%). For Group A, the time for patients in the three classes to achieve the efficacy endpoint increased significantly with disease progression (3.00, 6.78, and 8.29 days for Class A, B, and C, respectively). Conclusions Gastroparesis external application prescription can effectively treat gastrointestinal tumor postsurgical gastroparesis and may be more efficacious in progressive disease compared placebo. Patients with gastrointestinal tumor postsurgical gastroparesis should therefore undergo intervention at an earlier stage.

The service life of reinforced concrete (RC) structures in marine environments is mainly influenced by the chloride-induced corrosion of reinforcement, and the development of chloride penetration model is essential for its assessment. The empirical Fick’s second law of diffusion provides a simple way to predict the chloride penetration in practical situations. However, the derivation of parameters of this model is mainly based on the results of laboratory experiments or field exposure trials, and these parameters need to be calibrated with long-term field results of real structures. The filed investigations of seventeen high-pile wharf structures located at the south coast of China were carried out, and the results were compared with the long-term exposure test results in terms of chloride ingress profile. The probability models for surface chloride content and chloride diffusion coefficient were derived according to these results; and finally the effects of different models of chloride ingress parameters, based on exposure trails or based on real structure surveys, on the expected service life of marine structures were investigated.

The intensity and/or frequency of hurricane storms may change due to the impact of potential climate change. This paper presents a probabilistic framework to assess the hurricane damage to residential constructions considering the non-stationarity and correlation in hurricane actions. The framework includes a non-stationary Poisson process of hurricane occurrence, a failure rate function of hurricane damage, and explicit formulas for evaluating the mean and variance of annual hurricane damage. The framework is illustrated using a case study of Miami-Dade County, Florida, where the current probabilistic models of hurricane intensity and occurrence rate were estimated by examining hurricane history in this area. The impacts of time-variant hurricane intensity and time-variant hurricane frequency on building damage are assessed individually using the developed framework. The paper also investigates the effects of correlation in hurricane wind speeds on hurricane damage.

Post-earthquake fire (PEF) is a hazardous secondary disaster following earthquake, and the multi-ignition of PEFs can result in huge economic loss and heavy casualties. The suppression of PEFs depends on the water distribution system (WDS) to provide water. Although a number of studies have been conducted to evaluate the firefighting capacity of WDS, their hydraulic modelling analyses fail to consider the influence of firefighting demand at one node on the water supply capability of other nodes, which may result in an overestimate of the WDS’ capability to suppress multiple simultaneous occurrence of PEFs. In this study, an integrated procedure is developed to evaluate the firefighting capacity of WDS under the effects of both seismic pipeline damage and multi-ignition of PEFs. Under the excitation of earthquakes with different intensities, the spatial distributions of PEFs and pipeline damage are simulated, and the associated uncertainties are included by Monte Carlo simulations. The firefighting capacity of WDS is defined as the probability of providing sufficient water to suppress multiple PEFs, which, combined with the probability distribution of ignition number of PEFs, can achieve the risk assessment of a city to suffer uncontrolled PEFs. The developed method is applied to a WDS currently operating in a Chinese city. Discussions are made on the influences of multiple simultaneous water demands on firefighting capacity evaluation of WDS and the possible applications of the proposed method.

Background Gastroparesis affects the quality of life of many patients, but there is no effective treatment. Now, complementary and alternative medicine originated from China is gradually accepted by the world because of its unique treatment principles and relatively safe treatment methods. However, at present, there is still a lack of more definitive clinical application evidence for the treatment of gastroparesis with complementary and alternative medicine to confirm the safety and efficacy of complementary and alternative medicine in the treatment of gastroparesis caused by various causes. More comprehensive and stronger evidence-based medicine evidence is needed. Methods We will retrieve literatures using Medline, Embase, the Cochrane Library database, Web of science, CNKI, VIP, CBM, and WanFang. We will look for RCTs or CCTs on the use of complementary and alternative medicine in the treatment of gastroparesis, and extract relevant data into the excel sheet. The whole retrieval and data extraction process were carried out by 2 researchers independently. Then we will use meta-analysis to make statistical analysis of all the results and make a systematic review of all the included literatures. Results All results and safety data were analyzed for a comprehensive evaluation and/or descriptive analysis of the efficacy and safety of complementary and alternative therapies for gastroparesis. Conclusion This study will provide more comprehensive clinical evidence for the treatment of gastroparesis with complementary and alternative therapies. Registration The research has been registered and approved on the INPLASY.COM website. The registration number is INPLASY2020100033.

Concrete structures may deteriorate over time due to aggressive service environments, leading to a reduction in their strengths, stiffnesses and reliabilities. In general, the assessment of time-dependent reliability of ageing structures must consider uncertainties in structural deterioration as well as non-stationarities in the structural load processes. This paper develops an approximate method for assessing the impact of structural deterioration and non-stationary live loads on structures, which requires only low-dimensional integration and reduces the cost of assessing time-dependent reliability over a service life extending to 50 years significantly. This approximate method is demonstrated through several examples. The importance of non-stationarities in the resistance and load processes on time-dependent reliability is illustrated and the accuracy of the method is confirmed in several cases utilising Monte Carlo simulation.

Effective length method is still widely used in engineering practice to evaluate the stability of compression members in frame structures. However, the conventional effective length method can be inaccurate in many cases as it considers columns in isolation from the stories above and below. This article proposes an improved method for simplified frame stability analysis that accounts for the vertical interaction effects of columns. The idealized sub-assemblage model includes the columns of all stories and their restraining beams. The stability matrix for a single-story unit is first derived, and then the system stability matrix is obtained by considering the compatibility of the story units. The governing equation for the elastic buckling load of the sub-assemblage is derived. The method is applicable to both sway-permitted and sway-prevented frames. The applicability and accuracy of the proposed method are demonstrated using a series of examples with a wide variation of parameters including numbers of story, boundary conditions, stiffness of beam-to-column connections, column length and stiffness, and axial force level.

This paper performs the durability assessment of concrete structures during construction phase in the ongoing large-scale Hong Kong-Zhuhai-Macau (HZM) project with a service life of 120 years. The background of this project is first introduced and the durability design at preliminary study phase is recalled. Then, the durability model for assessment is established for HZM and the statistical properties of the model parameters are given. From the collected data on the chloride diffusion coefficients and concrete cover thickness, the statistical properties of these parameters are updated. With the design options adopted in design phase and the updated parameter properties, the achieved reliability levels are calculated for structural elements under different exposure conditions for both normal and accidental working cases. On the basis of the achieved reliability level of durability, a preliminary maintenance planning is performed for the RC/PC elements in the concrete structures, and the corresponding recommendations are given.

Bridge resistance and reliability may deteriorate with time due to aggressive environmental conditions and increasing road freight volumes, resulting in an increase of potential economic loss. This is thus a great concern to decision-makers managing the bridges’ continued future service. Reasonable models of bridge resistance and applied loads are the fundamentals of accurate estimation/prediction of a bridge’s serviceability. In this paper, a new model for resistance deterioration is proposed, which enables the non-increasing property and auto-correlation in the stochastic deterioration process to be incorporated. To facilitate the practical application of the model, methods to determine its parameters using obtained data on structural resistance are developed and illustrated through simple numerical examples. Time-dependent reliability analysis is conducted using the proposed resistance deterioration model based on Monte Carlo simulation, and the effect of auto-correlation in the deterioration process on structural time-dependent reliability is investigated.

This paper presents the durability design of concrete structures in the Hong Kong–Zhuhai–Macau (HZM) sea link project for a design service life of 120 years. Among all the durability issues, this paper focuses on the model-based durability design of concrete structures in the project subject to the action of marine chlorides. The mechanism and modeling of chloride penetration into concrete are reviewed in depth and the applicability of models for durability design is evaluated. On the basis of long-term exposure tests and in-place structural investigations during the past 30 years in South-eastern China, the design model for concrete structures in the HZM project is established. The statistical properties of model parameters are analyzed in details and compared to other chloride ingress models. Using the established HZM model for chloride ingress and specified durability limit state (DLS), the design parameters are first evaluated through a fully probabilistic analysis in terms of service lives (50 years, 120 years) and target reliability levels ( β = 1.3, 1.5, 1.8). The partial factor format for durability design is then established and the partial factors are calibrated from the first order reliability method (FORM) from specified service life and specified reliability level. The design results from the partial factor design equation are given for different exposure zones, and the achieved reliability index is verified for each design through the full probabilistic method. Finally remarks are given on the HZM model and its application in durability design of RC elements.

It has been shown that microRNA-215 (miR-215) is dysregulated in several human malignancies, and this correlates with tumor progression. However, its expression and function in pancreatic cancer is still unclear. The aim of this study was to explore the effects of miR-215 on pancreatic cancer formation and progression. Using quantitative RT-PCR, we detected miR-215 expression in pancreatic cancer cell lines and primary tumor tissues. The association of miR-215 expression with clinicopathological factors and prognosis was also analyzed. We then observed the effects of miR-215 on the biological behavior of pancreatic cancer cells. Lastly, the potential regulatory function of miR-215 on ZEB2 expression was investigated. miR-215 expression levels were significantly downregulated in pancreatic cancer samples and cell lines. Decreased miR-215 expression was significantly associated with large tumor size, advanced TNM stage, lymph node metastasis, vessel invasion, and lower overall survival. Multivariate regression analysis corroborated that downregulation of miR-215 was an independent unfavorable prognostic factor. Overexpression of miR-215 inhibited pancreatic cancer cell proliferation, invasion, and migration; promoted cell apoptosis in vitro; and suppressed tumorigenicity in vivo. Further, ZEB2 was confirmed as a direct target of miR-215 by using a luciferase reporter assay. These findings indicate that miR-215 may act as a tumor suppressor in pancreatic cancer cells, and could serve as a novel therapeutic target for miR-based therapy.

Civil infrastructure performance and reliability may be affected by deterioration in strength or stiffness caused by service or environmental conditions or by systemic changes in load beyond the baseline conditions assumed for design. These changes should be considered when assessing a structure for its continued future reliability in service. This paper presents an improved method for evaluating time-dependent reliability of structures taking these factors into account. The method enables the impact on safety and serviceability of non-stationarity in the load and resistance deterioration processes to be assessed quantitatively. Parametric analyses show that the reliability is sensitive to the load intensity at the end of the service period, moderately sensitive to the initial and final mean occurrence rates of load events and the nature of these increases in time, and relatively insensitive to the nature of the increase in mean load intensity. A realistic time-dependent model of structural resistance is proposed and the role played by the auto-covariance in the resistance degradation process is investigated. The auto-covariance in stochastic resistance plays a significant role in time-dependent reliability assessment. Assuming that the time-dependent resistance is ‘fully correlated’ generally gives a reasonable estimation of structural reliability, while assuming that the resistances are statistically independent at two points in time may cause the failure probability to be overestimated.

Evaluating the behaviour of deteriorating steel structures is complicated by the inherent uncertainties in the corrosion process. Theoretically, these uncertainties can be modeled using a probabilistic approach. However, there are practical difficulties in identifying the probabilistic model for the deterioration process as the actual corrosion data are rather limited. Also, the dependencies between different random variables are often vaguely known and, thus, not included in the modeling. This paper proposes a probabilistic analysis framework for modeling the atmospheric corrosion of steel structures with incomplete information. The framework is based on the theory of imprecise probability and copula. Two examples are presented to illustrate the methodology. The role of epistemic uncertainties on structural reliability is investigated through the examples.

Severe hurricanes in coastal areas have caused enormous human and economic losses. Furthermore, the intensity and frequency of future hurricanes may increase due to the potential impact of ...