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According to China's Seventh National Census, 18.70% of a total of 1.41 billion people were 60 or older and 13.50% were 65 or older, so China's population is increasingly aging. In conjunction with China's socioeconomic and scientific and technological development and its promotion of medical insurance-related policies, rational medication management for the elderly is a concern in order to control the risk of polypharmacy. This paper summarizes and discusses the following five key issues inherent in rational medication management: i) an increase in serious polypharmacy and the potential risks of medication; ii) a lack of medication consultation service and medication withdraw without healthcare providers' supervision; iii) poor medication compliance among the elderly; iv) insufficient quantity and incompetence of pharmaceutical staffing; and v) limited awareness of pharmaceutical services and lack of trust in the ability of pharmacists. Based on a discussion of factors influencing these issues, suggestions have been put forward in the hopes that China emphasizes rational medication management in order to reduce the risk of polypharmacy and the disease burden of the elderly in China.

The development of photosensitive slurries for additive manufacturing has attracted great interest due to their correlation with the final properties of the fabricated parts. This paper focus on the printing quality control in digital light processing (DLP) 3D printing of advanced ceramics. Systematic experiments were performed to assess the effects of the exposure time and printing angle on the three-point bending strength of the fabricated samples. The exposure time affected the bending strength of the printed zirconia ceramic dramatically. When the weak exposure time is 1 s and the strong exposure time is 13 s, the average bending strength can reach 580 MPa while Weibull modulus can reach 8.84. Meanwhile, the printing angle also affected the bending strength mechanical sample printed at 45° exhibits the worst performance.

Background: Dyslipidemia is one of the risks of coronary atherosclerosis disease (CAD). Intensive-dose statins or combining with ezetimibe are widely used to improve the lipid-lowering efficacy in the clinic. Recently, lipid variability has gradually gained attention to be a more reliable predictor of cardiovascular events. We aimed to investigate the variability in plasma lipids in the above two lipid-lowering strategy.Methods: It was a multicenter retrospective study, a total of 1275 patients with CAD from January 2009 to April 2019 were divided into 2 groups: intensive statins (atorvastatin 40 mg/d or rosuvastatin 20 mg/d) group and conventional-dose statins (atorvastatin 20 mg/d or rosuvastatin 10 mg/d) combined with ezetimibe group. All patients were followed up for at least 1-year. Multiple linear regression was used to analyze the association of two lipid-lowering regimens with plasma lipids variability; and subgroup analyses of the relevant factors were applied. All verifications are verified by standard deviation (SD), coefficient of variation (CV), and variability independent of mean (VIM) triple methods.Results: In the overall participants, the mean age was 62.3±10.4 years old, and 72.8% was male. Multivariate linear regression indicated that intensive statins group had lower variability in total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and non-high-density lipoprotein cholesterol (non-HDL-C) in all SD, CV, and VIM triple methods than statins combined with ezetimibe group (p for all Conclusions: Intensive statins therapy has lower variability in TC, LDL-C, and non-HDL-C, that is, better lipids stability than statins combined with ezetimibe therapy in patients with CAD.

The durability design of reinforced concrete (RC) structures that are exposed to aggressive environmental attacks (e.g., corrosion due to chloride ingress in marine environment) plays a vital role in ensuring the structural serviceability within a reference period of interest. Existing approaches for the durability design and assessment of RC structures have, for the most part, not considered the spatial distribution of corrosion-related structural properties. In this paper, a closed-form approach is developed for durability assessment of RC structures, where the structural dimension, spatial variability, and correlation of structural properties such as the concrete cover thickness and the chloride diffusion coefficient are taken into account. The corrosion and crack initiations of an emerged tube tunnel segment that was used in the Hong Kong-Zhuhai-Macau bridge project were assessed to demonstrate the applicability of the proposed approach. The accuracy of the method was verified through a comparison with Monte Carlo simulation results based on two-dimensional random field modeling. The proposed method can be used to efficiently assess the durability performance of RC structures in the marine environment and has the potential to become an efficient tool to guide the durability design of RC structures subjected to corrosion.

Bone metastasis is one of the most serious complications in lung cancer patients. MicroRNAs (miRNAs) play important roles in tumour development, progression and metastasis. A previous study showed that miR-106a is highly expressed in the tissues of lung adenocarcinoma with bone metastasis, but its mechanism remains unclear. In this study, we showed that miR-106a expression is dramatically increased in lung cancer patients with bone metastasis (BM) by immunohistochemical analysis. MiR-106a promoted A549 and SPC-A1 cell proliferation, migration and invasion in vitro. The results of bioluminescence imaging (BLI), micro-CT and X-ray demonstrated that miR-106a promoted bone metastasis of lung adenocarcinoma in vivo. Mechanistic investigations revealed that miR-106a upregulation promoted metastasis by targeting tumour protein 53-induced nuclear protein 1 (TP53INP1)-mediated metastatic progression, including cell migration, autophagy-dependent death and epithelial–mesenchymal transition (EMT). Notably, autophagy partially attenuated the effects of miR-106a on promoting bone metastasis in lung adenocarcinoma. These findings demonstrated that restoring the expression of TP53INP1 by silencing miR-106a may be a novel therapeutic strategy for bone metastatic in lung adenocarcinoma.

This study aimed to construct a widely accepted prognostic nomogram in Chinese high-grade osteosarcoma (HOS) patients aged ≤ 30 years to provide insight into predicting 5-year overall survival (OS). Data from 503 consecutive HOS patients at our centre between 12/2012 and 05/2019 were retrospectively collected. Eighty-four clinical features and routine laboratory haematological and biochemical testing indicators of each patient at the time of diagnosis were collected. A prognostic nomogram model for predicting OS was constructed based on the Cox proportional hazards model. The performance was assessed by the concordance index (C-index), receiver operating characteristic curve and calibration curve. The utility was evaluated by decision curve analysis. The 5-year OS was 52.1% and 2.6% for the nonmetastatic and metastatic patients, respectively. The nomogram included nine important variables based on a multivariate analysis: tumour stage, surgical type, metastasis, preoperative neoadjuvant chemotherapy cycle, postoperative metastasis time, mean corpuscular volume, tumour-specific growth factor, gamma-glutamyl transferase and creatinine. The calibration curve showed that the nomogram was able to predict 5-year OS accurately. The C-index of the nomogram for OS prediction was 0.795 (range, 0.703–0.887). Moreover, the decision curve analysis curve also demonstrated the clinical benefit of this model. The nomogram provides an individualized risk estimate of the 5-year OS in patients with HOS aged ≤ 30 years in a Chinese population-based cohort.

Elastic cables have the advantages of desirable seismic mitigation effect, low cost, and convenient installation, and have been used widely in low-to-mid-span bridges. However, their utiliz...

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...

Probability-based seismic performance assessment of in-service bridges has gained much attention in the scientific community during the past decades. The nonlinear static pushover analysis is critical for describing the seismic behaviour of bridges subjected to moderate to high seismicity due to its simplicity. However, in existing analysis methods, the generation of pushover curve needs tremendous amount of computational costs and requires skills, which may halter its application in practice, implying the importance of developing practice-oriented analysis method with improved efficiency. Moreover, the bridge pier performance has been modelled as deterministic, indicating that the variation associated with the pier material and mechanical properties remains unaddressed. The correlation in the performance of different piers also exists due to the common design provisions and construction conditions but has neither been taken into account. This paper develops a simplified pushover analysis procedure for the seismic assessment of simply supported RC bridges. With the proposed method, the pushover curve of the bridge can be obtained explicitly without complex finite element modelling. A random factor is introduced to reflect the uncertainty in relation to the pushover curve. The correlation in the pier performance is considered by employing the Gaussian copula function to construct the joint probability distribution. Illustrative examples are presented to demonstrate the applicability of the method and to investigate the impact of variation and correlation in bridge pier behaviour on the seismic performance assessment. Keywords: Seismic assessment, Simply supported RC bridge, Nonlinear analysis, Simplified method, Variation in pier behaviour, Correlation in pier behaviour

Background Cardiac hypertrophy is a serious factor underlying heart failure. Although a large number of pathogenic genes have been identified, the underlying molecular mechanisms of cardiac hypertrophy are still poorly understood. MicroRNAs are a class of small non-coding RNAs which regulate their target genes at the post-transcriptional level. L-type calcium channels play important role in hypertrophic signaling pathways, and CACNA1C is encoded by L-type calcium channels. Here, we hypothesize that the overexpression of miR-135b can attenuate hypertrophy by targeting CACNA1C. Methods We test the functional involvement of miR-135b in cardiac hypertrophy model. In order to evaluate the effect of miR-135b in cardiac hypertrophy, miR-135b mimic, miR-135b agomir and α-MHC-miR-135b transgenic mice were used for the overexpression of miR-135b. Luciferase reporter assays were used to testify the binding of miR-135b to the CACNA1C 3′UTR. Results Our results revealed that in a pathological cardiac hypertrophy model, the expression of miR-135b was clearly downregulated. Hypertrophic marker genes were upregulated after the knockdown of miR-135b in vitro, while the overexpression of miR-135b attenuated hypertrophy. These results suggested that miR-135b may weaken hypertrophic signals. We then explored the mechanism of miR-135b in hypertrophy and identified that CACNA1C was a target gene for miR-135b. The overexpression of miR-135b attenuated cardiac hypertrophy by targeting CACNA1C. Conclusions Our studies revealed that miR-135b is a critical regulator of cardiomyocyte hypertrophy. Our findings may provide a novel strategy for the treatment of cardiac hypertrophy.

Background: Ganglion cell paraganglioma is a subtype of neuroendocrine tumors, which is rare in clinical practice. Paraganglioma in the spinal area, especially in the spinal canal, is even rarer.Case presentation:The case we reported was a 46-year-old female who was admitted to the hospital due to "physical examination found a mass in the lumbar spinal canal for more than 2 months." After admission, the relevant examinations and preoperative preparations were perfected, and the posterior L2-3 spinal mass resection + spinal decompression + nail rod system internal fixation was performed. The patient recovered well after the operation, and there was no tumor recurrence in follow-up. Conclusions:Surgical treatment assisted by MRI neuroimaging and 3D printing reconstruction technology may be an effective way to treat paraganglioma in the lumbar spinal canal.

Objective Metastatic epidural spinal cord compression (MESCC) seriously affects the life span and quality of life of patients. Separation surgery combined with vertebroplasty combined with interstitial implantation of 125 I seeds (SSVPI) is a novel treatment for MESCC patients. To investigate the safety, feasibility and clinical efficacy on metastatic epidural spinal cord compression treated by SSVPI. Method Prospective analysis of 56 patients diagnosed with metastatic epidural spinal cord compression (MESCC) and receiving Separation surgery (SS) or separation surgery combined with vertebroplasty combined with interstitial implantation of 125 I seeds. Fifty-six patients were randomly divided into the SS group (26 patients) and SSVPI group (30 patients), and the differences in intraoperative bleeding, postoperative pain visual analog scale scores (VAS), Karnofsky performance scores (KPS) and American Spinal Injury Association grades were compared. Results There was no significant difference in intraoperative bleeding between the SS group and the SSVPI group ( P > 0.05). There was no significant difference at 1 week after surgery ( P > 0.05); there were significant differences in VAS scores at 2, 6 and 12 months after surgery ( P < 0.05). There was no significant difference in the KPS score 1 week after surgery ( P > 0.05); there were statistically significant differences in the KPS scores at 2, 6 and 12 months after surgery ( P < 0.05). In the SS group, there were 20 patients (76.92%) with an improvement in ASIA grades from pre- to postoperation. In the SSVPI group, there were 24 patients (80%) with improved ASIA grades from pre- to postoperation. Conclusion SSVPI is a safe, feasible, less invasive and effective treatment for MESCC patients.

The incidence and mortality of cardiovascular disease in diabetic patients are 2-3 times higher than those in non-diabetic patients. Abnormal function of the L-type calcium channel in myocardial tissue might result in multiple cardiac disorders such as a prolonged QT interval. Therefore, QT prolongation is an independent risk factor of cardiovascular disease in patients with diabetes mellitus. Metformin, a hypoglycemic agent, is widely known to effectively reduce the occurrence of macrovascular diseases. The aim of the present study was to evaluate the effect of metformin on prolonged QT interval and to explore potential ionic mechanisms induced by diabetes. Diabetic mouse models were established with streptozotocin and an electrocardiogram was used to monitor the QT interval after 4 weeks of metformin treatment in each group. Action potential duration (APD) and L-type calcium current (I Ca-L) were detected by patch-clamp in isolated mice ventricular cardiomyocytes and neonatal cardiomyocytes of mice. The expression levels of CACNA1C mRNA and Cav1.2 were measured by real-time PCR, western blot and immunofluorescence. A shortened QT interval was observed after 4 weeks of metformin treatment in diabetic mice. Patch-clamp results revealed that both APD and I Ca-L were shortened in mouse cardiomyocytes. Furthermore, the expression levels of CACNA1C mRNA and Cav1.2 were decreased in the metformin group. The same results were also obtained in cultured neonatal mice cardiomyocytes. Overall, these results verify that metformin could shorten a prolonged QT interval by inhibiting the calcium current, suggesting that metformin may play a role in the electrophysiology underlying diabetic cardiopathy.

Background: This study purposed to construct a widely accepted prognostic nomogram in Chinese high-grade osteosarcoma (HOS) patients aged ≤ 30 years to provide insight into predicting 5-year overall survival (OS). Methods: Data of 503 consecutive HOS patients at our centre between 12/2012 and 05/2019 were retrospectively collected. The 84 clinical features, routine laboratory haematological and biochemical testing indicators of each patient at the time of diagnosis were collected. A prognostic nomogram model for predicting OS was constructed based on Cox proportional hazards model. The performance was assessed by concordance index (C-index), receiver operating characteristic curve and calibration curve. The utility was evaluated by decision curve analysis. Findings: The 5-year OS was 52.1% and 2.6% for the nonmetastatic and metastatic patients, respectively. The nomogram included nine important variables based on a multivariate analysis: tumour stage, surgical type, metastasis, preoperative neoadjuvant chemotherapy cycle, postoperative metastasis time, mean corpuscular volume, tumour-specific growth factor, gamma-glutamyl transferase and creatinine. The calibration curve showed that the nomogram was able to predict 5-year OS accurately. The C-index of the nomogram for OS prediction was 0.795 (range, 0.703-0.887). Moreover, the decision curve analysis curve also demonstrated the clinical benefit of this model. Interpretation: The nomogram provides an individualized risk estimate of the 5-year OS in patients with HOS aged ≤ 30 years in a Chinese population-based cohort. Funding Statement: This work was financially funded by the National Science Foundation of China (No. U1702283, 81972764, 81960488, 81760520, 81560471), the Joint Special Funds for the Department of Science and Technology of Yunnan Province-Kunming Medical University (No. 2017FE467-073, 2018FE001-060, 2019FE001-152, 2019FE001-078), the Scientific Research Projects of Internal Research Institutions of Medicine (Nos. 2017NS196, 2017NS197, 2018NS069, 2018NS070), the Medical Leaders of Yunnan Province (No. D-201603), the Foundation of the Young and Middle-aged Academic and Technical Leaders of Yunnan Province (No. 2017HB051), China Postdoctoral Science Foundation (No. 2018M643798XB), Training program for 100 Young and middle-aged Academic and technical backbones of Kunming Medical University and the Major Scientific and Technological Achievement Cultivation Project of Kunming Medical University (No. CGPY201703). Declaration of Interests: The authors declare that they have no competing interests. Ethics Approval Statement: All human tissue experiments were approved by the Institutional Ethics Committee of the Third Affiliated Hospital of Kunming Medical University (Yunnan Cancer Hospital). Written informed consent forms for the experimental studies were obtained from the patients or their guardians.

Type 2 diabetes is a common metabolic disorder related to insulin resistance, or deficiency of insulin secretion, caused by decreased insulin sensitivity and destruction of islet structure and function. As the second human genome, the microbiota has been observed to have a growing relationship with diabetes in recent years. Microbiota imbalance has been hypothesized to be involved in the regulation of energy metabolism and the inflammatory immune response in diabetes. The present study aimed to investigate whether fecal microbiota transplantation (FMT) could alleviate the symptoms associated with type 2 diabetes. To this end, a type 2 diabetes mouse model was first established through the consumption of a high-fat diet combined with streptozotocin (100 mg/kg), and FMT was used to rebuild the gut microbiota of diabetic mice. Fasting blood glucose, oral glucose tolerance tests, and HbA1c levels were monitored, while the hypoglycemic effects of FMT were also observed. Insulin levels were tested by ELISA and related indexes such as HOMA-IR, HOMA-IS, and HOMA-β were calculated. We found that insulin resistance and pancreatic islet β-cells were improved after FMT treatment. Meanwhile, the markers of inflammation in the pancreatic tissue were detected by ELISA and immunohistochemistry, which indicated that inflammatory response decreased following FMT treatment. Furthermore, flow cytometry and western blot results revealed that FMT inhibited the β-cell apoptosis. Here, the effect of FMT on hypoglycemia in type 2 diabetes was addressed by improving insulin resistance and repairing impaired islets, thereby providing a potential treatment strategy for type 2 diabetes.

The historical vehicles passed through an existing bridge can be regarded as proof-loading tests for the bridge, and, as a result, are evident of the bridge’s performance. Such service history information has been utilized to update the estimate of bridge resistance in previous studies with the help of a Bayesian method, where the resistance deterioration process was assumed to be independent of the vehicle load process. This assumption is, however, untenable in many cases where the deterioration stochastic process is statistically correlated with the load process (e.g., a greater load intensity may affect/accelerate the deterioration of structural resistance and the accumulation of structural fragility). With this regard, this paper investigates the effect of correlation between the resistance deterioration and load processes on updating the resistance of aging bridges with prior service load information. The copula function is employed to model the joint distribution of the correlated deterioration and load processes, with which the correlation is measured by the Kendall’s tau. A new method is developed in this paper to assess the updated bridge resistance taking into consideration the deterioration-load dependency in an explicit form. The applicability of the proposed method is illustrated using an existing RC beam bridge. The sensitivity analysis is conducted to examine how the deterioration-load dependency affects the updated resistance of service-proven aging bridges.

Study Design: Meta-analysis. Background: Although some new insights have been offered for clinical and scientific relevance, minor progress has been made in osteosarcoma treatment after a dramatic survival improvement in the late 1980s with the addition of chemotherapy to surgery. Intensified chemotherapy strategies have been suggested to increase the survival rate of patients with osteosarcoma. We performed this study to access whether intensified chemotherapy strategiesincreased survival outcomes of osteosarcoma patients compared with conventional chemotherapy strategies. Methods: MEDLINE/PubMed, EMBASE, BIOSIS Previews, and Cochrane Library were searched from database set up to October2016. Randomized controlled trials (RCTs) and comparative clinical trials (CCTs) on intensified versus conventional chemotherapy strategies for osteosarcoma patients met the inclusion criteria, and the methodological quality standard were retrieved and reviewed. Data on participant characteristics, interventions, follow-up period, and outcomes were extracted from the included studies and analyzed by Review Manager 5.3. Results: 12 studies (8 RCTs and 4CCT) involving 4112 patients were selected. There were no significant differences between intensified and conventional chemotherapy strategies group in 3-year event-free survival (OR, 1.01; 95% CI, [0.74–1.37]; P = 0.97), 5-year event-free survival (OR, 1.00; 95% CI, [0.86–1.17]; P = 0.97), and 5-year overall survival (OR, 1.04; 95% CI, [0.87–1.26]; P = 0.64), and good histologic response to preoperative chemotherapy (OR, 1.12; 95% CI, [0.78–1.60]; P = 0.55). Pooled analysis of local recurrence rate showed that local recurrence rate was significantly decreased in the intensified group compared with that in the conventional group (OR, 0.60; 95% CI, [0.42–0.85]; P = 0.004). Conclusions: Intensified chemotherapy might not be a preferred treatment for all of the osteosarcoma patients. Keywords: Meta-analysis, High dosage, Chemotherapy, Osteosarcoma

The deflections of retaining structures during deep excavation should be controlled below a predefined threshold in an attempt to mitigate the deformation-posed damage to the surrounding buildings and infrastructure facilities. In this paper, a new approach is presented to conducting deformation reliability assessments of retaining structures. The method is based on an extension of the classical first-passage reliability problem and is applied on the spatial scale of the retaining structures. With the proposed method, the in situ monitoring data and the associated measurement error can be easily incorporated, which accordingly improves the assessment accuracy. Moreover, the proposed method has a closed-form solution, which is beneficial for the computation efficiency and its practical application. The method was applied to assess the retaining structure reliability in a foundation excavation of a subway station in Fuzhou, China. The accuracy of the analytical results was verified through a comparison with those of Monte Carlo simulation. It was shown that the proposed method can represent well, the deformation-based safety level of retaining structures.

An important element of time-dependent reliability analysis of civil structures is choosing a proper model for the applied loads. Stochastic process theory has been widely used in existing ...

The Hedgehog (Hh) signalling pathway is involved in cell differentiation, growth and tissue polarity. This pathway is also involved in the progression and invasion of various human cancers. Osteosarcoma, a subtype of bone cancer, is commonly seen in children and adolescents. Typically, pulmonary osteosarcoma metastases are especially difficult to control. In the present paper, we summarise recent studies on the regulation of osteosarcoma progression and metastasis by downregulating Hh signalling. We also summarise the crosstalk between the Hh pathway and other cancer-related pathways in the tumourigenesis of various cancers. We further summarise and highlight the therapeutic value of potential inhibitors of Hh signalling in the clinical therapy of human cancers.

Aging of structural performance and significant external loads may impair structural safety and serviceability and cause potential economic losses. In the presence of uncertainties associated with both resistance deterioration and external loads, structural safety shall be estimated quantitatively under a probability-based framework. A stochastic load process is often auto-correlated on the temporal scale, with correlations arising from both the occurrence times and intensities. Moreover, a deterioration process is physically dependent on the load magnitudes. This paper investigates the impacts of load temporal correlation and deterioration-load dependency on time-variant structural reliability. The load occurrence process is modeled as a Poisson point process with correlated separation time between two load events. The correlation between the intensities of load events is described by the multi-variate Gaussian copula function. The resistance aging process is considered to be a combination of both gradual and shock deteriorations. Four candidate copula functions, namely Gaussian, Clayton, Gumbel and Frank, are considered to model the dependency of shock deterioration on load intensity. Two types of failure mechanisms are considered: the first is due to the load effect exceeding the resistance, and the second occurs when the cumulative damage within the considered service period reaches the permissible level. A simulation-based method is developed to estimate structural reliability considering the two failure modes. Illustrative examples are presented to demonstrate the applicability of the proposed method. Parametric studies are conducted to investigate the impacts of temporal correlation in loads and deterioration-load dependency on structural failure probability.

In-service civil structures are often subjected to repeated external loads (shock events), which may lead to an accumulation of structural damage and further an increase in the probability of structural failure. The shock actions are by nature stochastic with randomness arising from their intensities and occurrence times. A varying trend in future intensity and/or occurrence rate of many types of shock action has been projected in the literature, such as cyclone actions due to the potential impact of climate change. This article proposes a method to assess the structural reliability in the presence of uncertainty and non-stationarity in external shock events, with a limit state that the cumulative damage exceeds the permissible level. The mean value and variance of the cumulative damage are estimated with proposed closed-form solutions, and the gamma distribution is suggested to describe the probabilistic characteristics of the cumulative damage, whose accuracy is verified through a comparison with Monte Carlo simulation. Furthermore, the cumulative density function of structural service life is derived explicitly. Parametric studies are conducted to investigate the impact of non-stationarity in shock actions on structural reliability.

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.

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 ...

The prognostic value of nonsentinel lymph-node (NSLN) status in breast cancer remains unclear. This study was designed to investigate the prognostic value of NSLN status in SLN-positive breast cancer. Retrospective 873 consecutive primary breast cancer patients from a single institution who were SLN-positive and underwent axillary lymph-node dissection (ALND) were included. Patients with incomplete clinical information or loss of follow-up were excluded. Survival analysis in patients with the same number of positive LNs and patients belonging to the same American Joint Committee on Cancer (AJCC) node (N) classification was performed to establish a proposal for incorporating the NSLN status into the breast cancer staging system. The median follow-up was 41 months. Positive NSLN status was a significantly unfavorable factor for recurrence-free survival (RFS) (HR: 4.31, P

In this paper, the millimeter wave radar amplification device is designed using the MWG303 power amplifier chip of Milliway Electronic Technology Co., Ltd. The whole device comprises an input waveguide microstrip transition structure based on Rogers 5880 and an output waveguide microstrip transition structure based on quartz. And waveguide structures such as waveguide turn and waveguide lift, in this design, the waveguide microstrip transition circuit is designed and simulated in the 3D electromagnetic field simulation software HFSS of Ansoft Company, and then the parts are combined, and the micro-assembly test is carried out after CAD processing. The results show that the gain can reaches more than 10dB. The design has the advantages of high gain, good flatness, practical structure and so on.

The performance of an aging structure is commonly evaluated under the framework of reliability analysis, where the uncertainties associated with the structural resistance and loads should be taken into account. In practical engineering, the probability distribution of resistance deterioration is often inaccessible due to the limits of available data, although the statistical parameters such as mean value and standard deviation can be obtained by fitting or empirical judgments. As a result, an error of structural reliability may be introduced when an arbitrary probabilistic distribution is assumed for the resistance deterioration. With this regard, in this paper, the amount of reliability error posed by different choices of deterioration distribution is investigated, and a novel approach is proposed to evaluate the averaged structural reliability under incomplete deterioration information, which does not rely on the probabilistic weight of the candidate deterioration models. The reliability for an illustrative structure is computed parametrically for varying probabilistic models of deterioration and different resistance conditions, through which the reliability associated with different deterioration models is compared, and the application of the proposed method is illustrated.

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.

The cadmium sulphide (CdS) film is grown on cadmium telluride (CdTe) nanorods (NRs) arrays by different methods such as chemical bath deposition (CBD), magnetron sputtering (MS), and homogenous precipitation (HP) techniques. The impact of various deposition methods is explored in detail on the growth of CdTe/CdS composite film, the CdTe/CdS interface property, and solar cell efficiency. Compared to the CBD and HP methods, the MS method can improve the growth of the CdS on CdTe NRs with high crystalline quality. The device based on the CdS film prepared by the MS method demonstrates excellent photovoltaic performance, which has the potential for applications in solar cells.

Osteosarcoma (OS) is the most common type of primary bone tumor in children and adolescents and has been associated with a high degree of malignancy, early metastasis, rapid progression and poor prognosis. However, the use of adjuvant chemotherapy improves the prognosis of patients with OS. OS chemotherapy is based primarily on the use of adriamycin, cisplatin (DDP), methotrexate (MTX), ifosfamide (IFO), epirubicin (EPI) and other drugs. Previous studies have revealed that the survival rate for patients with OS appears to have plateaued: 5-year survival rates remain close to 60%, even with the use of combined chemotherapy. The most limiting factors include complications and fatal toxicity associated with chemotherapy agents, particularly high-dose MTX (HD-MTX), for which high toxicity and great individual variation in responses have been observed. Docetaxel (TXT) is a representative member of the relatively recently developed taxane class of drugs, which function to inhibit OS cell proliferation and induce apoptosis. Recently, more clinical studies have reported that TXT combined with gemcitabine (GEM) is effective in the treatment of OS (relapse/refractory and progressive), providing evidence in support of potential novel treatment strategies for this patient population. However, there is still no global consensus on this type of chemotherapy approach. The present review summarizes current studies surrounding progress in the chemotherapeutic treatment of OS and discusses the advantages and potential feasibility of TXT+GEM in the treatment of OS.

Honeycomb sandwich structures were widely used in lightweight design. However, the difficulties with the fabrication process actually highly limit their practical usage, especially for ceramic materials. In this paper, 3 mol% yttria-stabilized ZrO2 (3Y-TZP) honeycomb sandwich structures with square and hexagonal cell were prepared successfully by using digital light processing (DLP) printing method. With a base material density of >6.02g/cm3, square/hexagonal honeycomb sandwich structures with structural density of 42.89%-66.24% were achieved by modifying unit cell wall thickness. It can be concluded that square honeycomb cell is preferred for getting higher bending strength at the same structural density.

As a new additive manufacturing method, DLP has the advantages of high precision, fast speed and low cost. ZTA ceramic is anticipated to be used in more applications due to its superior bending strength, fracture toughness and thermal conductivity. But the detailed study with ZTA printing material for DLP is still rarely reported. In this experiment, ZTA ceramic UV resin with various ZrO2 concentration (5-15wt.%) were investigated and tested for their 3D printing performance. ZTA ceramic UV resin with low viscosity (−1) and high solid load (55vol.%) were successfully developed. After sintering at a temperature of ⩾ 1600°C, a relative density of >96% can be always promised. For the optimized doping level of ZrO2 at 11wt%, a density of 99% can be achieved.

Silicon nitride (Si3N4) ceramics are widely used in mechanical and thermal management applications due to their excellent properties. To overcome the difficulties in traditional Si3N4 ceramic forming techniques, it is interesting to see the possibility of making complex-shaped silicon nitride ceramic component with novel 3D printing methods. In this study, we aim to study the effect of photo-initiators on the curing behavior of pre-formulated Si3N4 ceramic UV resin suspension. To elucidate the potential multi-factor interactions, a statistic experiment design was implemented in a sequence of screening and optimization by using Modde software. It was found that the kinds of photo-initiators, total amount of initiators and the mixture ratio between initiators have a great influence on the curing properties of silicon nitride UV ceramic resin. Based on these results, a formula was selected based on the criterion of using least amount photo-initiator while reaching the highest curing thickness.

Compressive strength is one of the most important mechanical properties for cellular ceramics. But the dependence of compressive strength of highly porous cellular ceramic structures on porosity remains unclear due to the limit of available methods for making such strong structures based on specific structural designs. In this paper, the TPMS structures, namely P-cell, and neovius structure, were prepared based on the DLP 3D printing technology. Samples with various unit cells were fabricated with zirconia. The relative density of the sintered samples exceeds 99%. The effects of cell number on the compressive strength and deformation of the model were investigated. Samples with similar relative densities exhibited comparable mechanical property in aspect of compressive strength. It is very interesting that the cell number eventually only influence the total strain.

Cellular structure has been applied in lightweight engineering application because of its high specific strength, high modulus and low relative density. Here we used 3Y-TZP ceramic to realize two typical cellular structures, Kelvin and Octet-truss, through a novel digital light processing (DLP) 3D printing method. The strut size was changed systematically to generate structures with porosities in the range of 10% ∼ 80% and the bending strength of these structures were investigated and analyzed by three-point bending test.

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.

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.

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 ...

Power line carrier (PLC) technology plays an increasingly important role in the realization of cost-effective communication in a smart distribution grid. No current channel modeling method is universally applicable to more complex topologies that may emerge in smart grids, such as ring and mesh topologies. This paper presents a novel PLC channel modeling method based on the information node concept, and the universality and feasibility of the proposed method are demonstrated with applications in modeling networks with ring and mesh topologies. The factors that affect the channel characteristics of the networks and the laws that govern their behaviors for different types of topologies are analyzed. The validity and effectiveness of the proposed method are proven using simulation and laboratory tests. This paper provides the necessary theoretical basis and technical means to design the PLC modulation method for smart distribution grids.

The laparoscopic instruments cause pain, numbness and damages to surgeons during the operation due to poor ergonomic design. Anthropometry is one of the most important factors in ergonomic design. Six hand dimensions have been measured in gripping position of fourteen subjects. A prototype handle was designed based on those anthropometric data and finally manufactured. In this study, surface EMG and angels of wrist during a simulated laparoscopic task were collected to evaluate the usability of the new designed and an available handle. After the task, a questionnaire was used to assess the comfort level of those handles subjectively. The compare of those physiological signals showed that the prototype was superior in ergonomic design. Regarding to the questionnaire, the prototype handle scored 58.08, and the current handle scored 52.22. The results showed that the prototype handle is more ergonomic designed than the current handle.

A surface pressure distribution test system of a doctor’s hand during a laparoscopic surgery based on LabVIEW was designed. The principle was that real time acquisition of data signal on multi-channel sensors, and using data acquisition card to get the feed back voltage signal from these pressure sensors, and then transferred to a PC. The test system had realized the real time processing and display of the signal on LabVIEW. The pressure detection range was 0-210g. The system could detect the surface pressure real time of the part of a doctor’s hand which contacting the surface of handle during the laparoscopic surgical procedure. This system could also make quantitative evaluation of the contact pressure on the handle of the laparoscopic instruments and provide a reference to ergonomics design of the handle.

The successful past performance of an existing bridge is evidence of its resistance, which reduces the uncertainty associated with the resistance and so increases the bridge reliability. However, the resistance deterioration and increases in traffic load may negate this effect. In this paper, statistical techniques are used to combine the prior estimate of time-dependent resistance with new information from the service load history, thereby obtaining an updated estimate of bridge resistance, as well as an updated reliability for subsequent years. The application of the method is illustrated using an existing bridge. The influences of the intensity and nonstationarity of service load history and the shape and variance of deterioration function on updated estimates of bridge resistance and reliability are examined using parametric examples. It is found that the updated resistance of an existing bridge with ever-increasing traffic load is close to that of the same bridge with a stationary traffic loa...

This paper introduces the studies of self-heat conserving facade panel with abandoned polypropylene fiber. The optimum process conditions were studied. The tensile properties, bending and impact properties of external insulation panel were tested. The results show that when the hot-pressing temperature is 180°C , the tensile, bending and impact of external insulation panel are best. The optimum process is hot-pressing temperature of 180 °C, hot pressure of 10MPa, hot-pressing time 12 Min. The physico-chemical properties were tested. The results show that the data of each test is up to the china national standard .The heat insulation property was tested, the results show that the panels have good insulation performance. The wallboard is light and easy to transport. Because the raw material adopts recycled polypropylene fibers, the price is low and the insulation is good. Recycled fiber-plastic composite is filled with bright future prospects.

The initiation, propagation and broadening of crazes in polycarbonate were studied with the aid of polarizing microscopy. A loading instrument supplying uniaxial stretch is designed to match polarizing microscopy. With polarizing microscopy, online observations of crazes and stress field can be done simultaneously. Crazes appear in bilateral anteriority of the crack tip and direction of length is perpendicular to the maximum principal stress. Stress on the boarder of the crazing zone is taken as the initiating point of the crazes and length to time of crazes follows exponent law. The initiation, propagation and broadening of crazes is a time-dependent process.

A finite element model (FEM) is developed to simulate the temperature distribution in the sample/die/punch assembly during the spark plasma sintering (SPS) process. A thermal–electrical coupled model with temperature dependent thermal and electrical properties is implemented. The simulation studies were conducted using COMSOL and a range of heating-rates and die sizes were considered. Also, both temporary and equilibrium condition during heating process were evaluated in order to express the real temperature development in the sintering. During the spark plasma sintering process, the temperature difference between the sample center and the die surface depend on the heating-rate and die size. The simulation results also revealed that the temperature gradient during the heating process is much bigger than that in the dwelling period. It is necessary to consider the temporary state during the spark plasma sintering process in order to guarantee a well–controlled microstructure, especially in non-conductive ceramic materials.