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AbstractInsufficient adhesion between ultrathin wearing courses (UTWCs) and substrate layers can result in pavement distress. Epoxy asphalt exhibits potential as a tack coat due to its high bonding strength and thermal stability. However, its rapid curing may pose challenges to construction schedules. This study aimed to optimize the formulations of epoxy asphalt tack coats (EATCs) to enhance the interfacial adhesion and working performance of UTWCs. The adhesion of EATCs was evaluated through rotational viscosity and tensile tests. Design parameters were optimized using analysis of variance and microscopic tests. Road performance was assessed via interlayer shear and tensile testing on three pavement structures. The results indicated that the curing agent strongly influenced the properties and curing kinetics of EATCs. Formulations containing complex polysebacic polyanhydride (CPSPA-EA) exhibited superior bonding while meeting construction schedules. Microscopic analysis of CPSPA-EA revealed a stable crosslinked network formed at 30% binder dosage. The amount of spraying significantly impacted the adhesion in UTWC structures. The optimal spraying amounts were 0.60 kg/m2 for asphalt concrete (AC-13), 0.55 kg/m2 for stone matrix asphalt (SMA-13), and 0.40 kg/m2 for cement concrete substrate layers. These findings presented an optimization framework for designing EATCs to enhance UTWCs working and long-term performance through balanced tack formulations and application parameters. [ABSTRACT FROM AUTHOR]

We conducted a community-based cohort study to predict the 3-year occurrence of chronic kidney disease (CKD) among population aged ≥60 years. Participants were selected from two communities through randomized cluster sampling in Jiading District of Shanghai, China. The two communities were randomly divided into a development cohort (n = 12012) and a validation cohort (n = 6248) with a 3-year follow-up. Logistic regression analysis was used to determine the independent predictors. A nomogram was established to predict the occurrence of CKD within 3 years. The area under the curve (AUC), the calibration curve and decision curve analysis (DCA) curve were used to evaluate the model. At baseline, participants in development cohort and validation cohort were with the mean age of 68.24 ± 5.87 and 67.68 ± 5.26 years old, respectively. During 3 years, 1516 (12.6%) and 544 (8.9%) new cases developed CKD in the development and validation cohorts, respectively. Nine variables (age, systolic blood pressure, body mass index, exercise, previous hypertension, triglycerides, fasting plasma glucose, glycated hemoglobin and serum creatinine) were included in the prediction model. The AUC value was 0.742 [95% confidence interval (CI), 0.728–0.756] in the development cohort and 0.881(95%CI, 0.867–0.895) in the validation cohort, respectively. The calibration curves and DCA curves demonstrate an effective predictive model. Our nomogram model is a simple, reasonable and reliable tool for predicting the risk of 3-year CKD in community-dwelling elderly people, which is helpful for timely intervention and reducing the incidence of CKD. [ABSTRACT FROM AUTHOR]

The deformation behaviour of the asphalt concrete (AC) depends on the loading state and the temperature, accompanied by a large number of microcracks. In this study, the deformation and failure behaviour of the AC under uniaxial compression were investigated by the acoustic emission (AE). Both the stress–strain relationship and the energy dissipation were employed to analyse the macroscopic deformation of the specimen at low and medium temperatures. The AE parameters including count, energy and amplitude were measured in real-time during the loading process. The damage morphology of specimens was characterised by the failure location with the AE technology. Results show that with the rise of the temperature, the strength of AC specimens gradually decreased, which leads to a lower capacity in storing strain energy. The dissipative energy is greatly affected by the damage degree of the specimen. Both the event count and amplitude increased rapidly when the specimen failure occurred. The AE parameters are relatively sensitive to the deformation failure of asphalt mixtures influenced by the temperature. Furthermore, the results also imply that the AE method used in the present study to characterise the deformation failure in pavement engineering is more scientific and precise. [ABSTRACT FROM AUTHOR]

Hypertension has become increasingly prevalent in Chinese children and adolescents in recent decades, which affects growth and development of children, leads to cognitive decline and multiple target organ damage. Here, we assessed the impact of different body mass index (BMI) trajectories on the occurrence of hypertension in children and adolescents using a cohort study in Northeast China. Children and adolescents aged 5–18 years was extracted for physical examination in Fuxin City, Liaoning Province, China during the 2009–2015 period. A latent category growth mixed model (LCGMM) was used to classify BMI changes and analyze the effect of different BMI trajectories on the risk of occurrence of hypertension in these participants within 5 years. All participates were divided into five BMI trajectories by LCGMM method: slow increasing group (n = 2616, 30.8%), overweight and obesity (OW/OB) group (n = 1141, 13.4%), normal decreasing group (n = 232, 2.7%), stable normal group (n = 4383, 51.6%), and fast-increasing group (n = 120, 1.4%). Compared with the stable normal group, the slow increasing group [adjusted odds ratio (AOR): 1.610, 95% confidence interval (CI): 1.304–1.989], the OW/OB group (AOR: 3.172, 95% CI: 2.500–4.023) and the fast-increasing group (AOR: 2.708, 95% CI: 1.445–5.074) all increased the risk of developing hypertension in children and adolescents. The potential of developing hypertension varies among groups of children aged 5–18 with different BMI trajectories. Children and adolescents in the normal BMI range (the slow growth group) still need to be aware of the change in BMI trajectory to stop or slow down the progression of BP abnormalities. Five body mass index trajectories from ages 5–18 years were determined using the LCGMM method, which labeled as the slow increasing group, overweight and obesity (OW/OB) group, normal decreasing group, stable normal group, and fast-increasing group. Different BMI trajectories in children and adolescents aged 5–18 years are differentially associated with the development of hypertension. Increased BMI levels in children and adolescents increase the risk of hypertension. Moreover, even within the normal BMI range, a modest growth might raise the risk of high-normal BP. [ABSTRACT FROM AUTHOR]

The Monte Carlo simulation (MCS) has been developed to estimate the strength distributions of heterogeneous materials influenced by different factors. The method presents a statistical correlation between the macroscopic properties and the non-uniform characteristics at meso scale. This study proposes an extensive MCS to investigate the influence of the aggregate morphology on deformation behaviour of unbound granular materials (UGMs) based on a real aggregate library and the discrete element method. Two indexes, elongation index (EI) and flatness index (FI), were used to evaluate the morphological characteristics of 3D aggregates rebuilt by the X-ray CT technique. Furthermore, repeated load triaxial tests of UGMs were simulated by 50 MCS samples. The effects of shapes and sizes of aggregates on deformation behaviours were statistically analysed. The results show that the deformation behaviour is dependent on the size and the EI distribution, but insensitive to the loading frequencies and FI distribution. [ABSTRACT FROM AUTHOR]

In order to build an appropriate prediction model of pavement friction coefficient attenuation, the effects of aggregate texture, on a basis of texture scanning and pavement testing of the dynamic friction coefficient, traffic volume, and rock characteristics on pavement slide decay resistance were studied, and the accuracy of the developed prediction model of friction coefficient was thereafter compared and analysed. First, based on the tire-pavement dynamic friction analyzer independently developed by the research group, accelerated loading tests under different traffic conditions were conducted by the orthogonal test method, and the dynamic friction coefficient of pavement during the abrasion process was recorded. At the same time, the non-contact laser profile measurement system was used to collect three-dimensional micro-texture data of coarse aggregate surface at different abrasion stages, and characteristic parameters such as height, wavelength, and shape were calculated. Second, the factors such as traffic volume and rock characteristics were incorporated, and the algorithms such as multiple linear stepwise regression, feedforward neural network, and random forest regression were adopted to develop estimation models of pavement friction. The results showed that the model constructed based on only texture feature parameters poorly represented pavement skid resistance. After introducing the two indicators of total traffic volume and rock type, the correlation coefficients of the model significantly improved, reaching 0.63, 0.58, and 0.82 respectively, indicating that the latter two factors have significant effects on the anti-skid attenuation of pavement. Moreover, the above three models can achieve satisfactory prediction results. In addition, when a large sample size can be obtained, a random forest algorithm is recommended to acquire higher prediction accuracy of pavement friction coefficient attenuation. [ABSTRACT FROM AUTHOR]

To reveal the fracture damage of asphalt mixture, an image-based numerical approach is proposed in this study considering the distribution of aggregate and asphalt mortar. Both digital image processing technique and discrete element method are applied to simulate the inhomogeneity of specimen and its fracture evolution at low temperature. At the same time, the acoustic emission (AE) activities are measured in laboratory to be compared with the micromechanical responses of numerical models. Results indicate that the developed method is suitable for modelling the numerical specimen of asphalt mixture, taking into account the size gradation and morphology of aggregates in the two-dimensional image. The numerical results of asphalt mixture have a good agreement with that of laboratory tests in cracking distribution and statistical probability. Cracks first appear on the aggregate–mortar interface, located in the upper and middle parts of the specimen, and then the brittle shear failure gradually propagates along the surface. Cumulative probabilities of both AE ringing counts and microfracture number follow the Weibull distribution. The numerical model has a significant advantage in the fracture evolution of asphalt mixture because the eccentric loading is unavoidable in laboratory tests due to personal and mechanical errors. [ABSTRACT FROM AUTHOR]

The cumulative permanent strain of subgrade soils plays an important role in the pavement structure design and long-term pavement performance maintenance. In Southern China, the hot and humid climate increases the risk of becoming a saturated condition for subgrade soils. The saturated subgrade soils will generate significant cumulative permanent strain under long-term cyclic loading compared with unsaturated soils. This study investigated the impact of the moisture content, number of cyclic loading, deviatoric stress and confining pressure on the evolution of the cumulative permanent strain for subgrade soils by using long-term cyclic (10,000 cycles) triaxial tests. The test results indicated that the cumulative axial permanent strain increase with the increasing moisture content, as well as the increasing number of cyclic loading and deviatoric stress but decreases with the increasing confining pressure. In order to predict the permanent deformation of subgrade soils in Southern China, a new model for predicting the permanent deformation of subgrade soil, which contains number of cyclic loading, initial bulk stress, octahedral shear stress and saturation, was proposed and validated. [ABSTRACT FROM AUTHOR]

This study aims at developing an efficient and accurate methodology to estimate the resilient modulus of subgrade soils. First, a new resilient modulus model incorporating stress dependence and moisture dependence was proposed. Second, prediction models were developed to conveniently and accurately determine model parameters of SWCC and resilient modulus model. In order to characterise the moisture dependence of subgrade soils, the matric suction was added into the proposed model. The matric suction was measured by the pressure plate test and the soil-water characteristic curve (SWCC) was used to determine the matric suction value at any given moisture contents. In order to develop prediction models for model parameters of SWCC and resilient modulus model, the laboratory experiments and multiple regression analysis were conducted on 22 soil samples. A series of performance-related soil properties were measured and used to develop the coefficients prediction models. The developed coefficients prediction models using the performance-related soil properties have high R-squared values and were validated by comparing the measured and predicted values of resilient modulus. Therefore, when the basic physical properties of soils were obtained, the resilient modulus can be predicted for the subgrade soils at any given matric suctions and stress states. [ABSTRACT FROM AUTHOR]

Objective: To explore the predictive role of pretreatment albumin to globulin ratio (AGR) for prognosis in lung cancer. Methods: A comprehensive literature retrieval was performed in the PubMed, Cochrane Library, Web of Science and EMBASE databases up to May 20, 2019. The pooled hazard ratio (HR) and 95% confidence interval (CI) were applied to assess the correlation of pretreatment AGR with overall survival (OS) and disease-free survival (DFS). Sensitivity analysis was performed to assess the stability of results. Bess's funnel plot and Egger's test were conducted to detect potential publication bias. Results: Eight articles involving 3496 patients were included in our meta-analysis and all studies were from Asian countries. The results demonstrated that a low pretreatment AGR was significantly associated with poor OS (HR = 1.88, 95% CI: 1.49–2.38, P<0.001) and DFS (HR = 2.09, 95% CI: 1.56–2.81, P<0.001) and sensitivity analysis indicated the stability of above results. Publication bias test showed that there were two potentially unpublished articles, but they did not have a significant influence on the results of our meta-analysis. Conclusion: Our study manifested that pretreatment AGR was a reliable predictor for survival and it may contribute to the risk evaluation and therapy strategy formulation of lung cancer patients. [ABSTRACT FROM AUTHOR]

Objective: In recent years, increasing studies found that pre-treatment red blood cell distribution width (RDW) could predict clinical outcomes in various cancers. However, the prognostic value of pre-treatment RDW in lung cancer was inconsistent. Therefore, we performed a meta-analysis to determine prognostic value of pre-treatment RDW in lung cancer. Methods: We performed a search in PubMed, The Cochrane Library, EMBASE (via OVID), Web of Science, CNKI, Wanfang, VIP, SinoMed databases, then we identified all records up to February 15, 2019. Outcomes of interest were overall survival (OS) and disease-free survival (DFS). Hazard ratios (HRs) and corresponding 95% confidence intervals (95% CIs) were calculated to assess the relevance of pre-treatment RDW to OS in lung cancer. Results: We included ten articles in total. Pooled results revealed that elevated pre-treatment RDW was significantly associated with poor OS (HR = 1.55, 95% CI: 1.26–1.92, p < 0.001) and DFS (HR = 1.53, 95% Cl: 1.15–2.05; p = 0.004) in lung cancer. Further subgroup analysis manifested that lung cancer patients with elevated pre-treatment RDW had worse prognosis. Conclusions: A higher value of pre-treatment RDW indicated worse survival of patients with lung cancer. RDW may serve as a reliable and economical marker for prediction of lung cancer prognosis. [ABSTRACT FROM AUTHOR]

Background: The association of four-limb systolic blood pressure differences (SBPDs) including inter-arm (IASBPD), inter-leg (ILSBPD) and ankle-brachial index (ABI) with cardiovascular risk factors and target organ changes (TOCs) remains controversial. This study aims at investigating the association of those parameters with cardiovascular risk factors and TOCs in an elderly Chinese population. Methods: A total of 1528 subjects derived from the Northern Shanghai Study were studied. Four-limb BPs were simultaneously measured by VP-1000 device. Cardiovascular risk factors and TOCs including parameters of left ventricular structure and function, carotid intima-media thickness, carotid-femoral pulse-wave velocity (CF-PWV), estimated glomerular filtration rate (eGFR) and urinary albumin/creatinine ratio, were evaluated with standardized methods. Results: ABI significantly associated age (β = −0.004, p <.01), female gender (β = 0.02, p <.01), body mass index (β = −0.004, p <.01), smoking (β = −0.04, p <.01), high-density lipoprotein (β = 0.04, p <.01), low-density lipoprotein (β = −0.01, p =.01) and diabetes mellitus (β = −0.02, p <.01), while the fourth root of IASBPD significantly associated with body mass index (β = 0.03, p <.01), high-density lipoprotein (β = −0.10, p =.02) and brachial SBP (β = 0.003, p <.01); the fourth root of ILSBPD significantly associated with high-density lipoprotein (β = −0.12, p <.01) and diabetes mellitus (β = 0.09, p =.01). IASBPD, ILSBPD, and ABI all significantly associated with CF-PWV and eGFR (all p <.05) in either unadjusted or adjusted models, but not with other TOCs. Conclusion: Four-limb SBPDs, namely ABI, IASBPD, and ILSBPD, bore various burdens of cardiovascular risk factors and significantly and independently associated with CF-PWV and eGFR. [ABSTRACT FROM AUTHOR]

A novel photoelectric integration process (MPEC) was developed to degrade Amaranth. In the MPEC, the output voltage of the microbial fuel cells (MFCs) was used to assist the dual slant-placed electrodes thin-film photocatalytic (PC). With two MFCs connected in series, the MPEC process realized the highest decolorization efficiency. It is close to that of the external bias photoelectrocatalytic (PEC), and 7% higher than that of the self-generated electric field-assisted photoelectrocatalytic (SPEC). The feasibility of MPEC pre-treatment and MFC post-treatment of Amaranth was investigated. The results demonstrated that MPEC pre-treatment of Amaranth could improve its biodegradability. The higher MPEC decolorization efficiency indicated the stronger biodegradability of the obtained intermediates and the higher MFC output voltage. When the MPEC decolorization efficiency was gradually increased to 50%, the removal efficiencies of total Chemical Oxygen Demand (COD) by the MPEC and MFC increased; when the decolorization efficiency was increased above 50%, the removal efficiencies became stable. MPEC enhanced the biodegradability efficiently and was applicable to pre-treat textile wastewater. [ABSTRACT FROM AUTHOR]

Background: The Eighth Joint National Committee Panel (JNC8) recommended a novel blood pressure (BP) goal for individuals with hypertension, which was less stringent than the Seventh Joint National Committee (JNC7) guideline and is still under debate. In our study, we aimed at finding a better BP goal for the elderly Chinese.Methods: About 1599 community-based elderly participants were recruited in the northern Shanghai and were classified by chronic kidney disease or diabetes mellitus to investigate their BP control conditions based on both the JNC7 and JNC8. Then, participants were categorized into four groups: normotensive individuals (Group 1), individuals at BP goal by JNC7 (Group 2), individuals at BP goal by JNC8 but not by JNC7 (Group 3), and individuals not at-goal by both guidelines (Group 4). Patients’ hypertensive target organ damages as left ventricular mass index (LVMI), peak transmitral pulsed Doppler velocity/early diastolic tissue Doppler velocity (E/Ea), pulse wave velocity (PWV), etc. were evaluated.Results: According to the JNC8, 19.0% of the population were reclassified as at-goal. Group 4 had significantly greater LVMI than Group 2 (96.5 vs 91.5 g/m2,p< 0.05) and also had significantly greater E/Ea (10.3 vs 9.7 and 10.3 vs 9.7,p< 0.05) and PWV (10.3 vs 9.3 m/s and 10.3 vs 9.7 m/s, p < 0.05) than both Group 2 and Group 3; however, there were no significant differences of these variables between Group 2 and Group 3.Conclusion: In the community-based elderly Chinese, the JNC8 hypertension guideline may set a better BP goal than the JNC7 in identifying patients’ left ventricular diastolic dysfunction and arterial stiffening. [ABSTRACT FROM PUBLISHER]

A dual slant-placed electrodes thin-film photocatalytic (PC) reactor was proposed and successfully applied to degrade Amaranth. In this PC reactor, both the TiO2/Ti photoanode and the Cu cathode are slant-placed in the reaction chamber, and aqueous thin-film formed on the surface of both electrodes as wastewater flowed over them. The degradation efficiency was significantly improved as a result of additional degradation at the cathode. When the TiO2photocatalyst was irradiated with UV light, photogenerated electrons were spontaneously transferred from the anode to the cathode, driven by the electric field self-generated between the TiO2/Ti anode and the Cu cathode, based on the principle of establishing a Schottky barrier. On the Cu cathode surface, the transferred photoelectrons either reacted with dissolved oxygen to form H2O2,which then oxidized the dye, resulting in indirect oxidation decolourization, or reacted with the dye, resulting in direct reduction decolourization. The colour removal efficiency of the cathode was about half that of the photoanode. These processes together with direct oxidation of the photogenerated holes on the photoanode gave dual electrode degradation of the dye, and the degradation efficiency was significantly improved. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the prevalence of chronic kidney disease (CKD) by stage in Chinese patients with coronary heart disease (CHD) and to identify the clinical features and examine control of cardiovascular risk factors. Methods and results: Clinical data of hospitalized patients were collected by investigators in China. CKD stages were classified according to estimated glomerular filtration rate (eGFR). A total of 2509 participants with CHD were included in the final statistical analysis. The overall prevalence of CKD stage 3 and greater (eGFR of less than 60 mL/min/1.73 m2) in the CHD patients was 32.5%. As the CKD stage increased, fasting blood glucose (FBG), systolic blood pressure (SBP), diastolic blood pressure (DBP), and high-sensitivity C-reactive protein (HS-CRP) levels all worsened. As the CKD stage became more severe, CHD patients had comorbidities such as diabetes mellitus, periphery arterial disease, and ischemic stroke, and more CHD patients had triple vessel disease increased. Even when patients received treatment of CHD and risk factors, control of cardiovascular risk factors such as SBP, DBP, FBG, and low-density lipoprotein was worsened as CKD stage became more severe over a 6-week follow-up. Conclusions: The data suggested a high prevalence of CKD in Chinese patients with CHD. Many conventional risk factors and comorbidities were correlated with high prevalence of CKD in CHD patients. Control of cardiovascular risk factors in those patients was poor. [ABSTRACT FROM AUTHOR]

Diffusive sampling combined with thermal desorption (DSTD) is considered useful in monitoring workers' exposures to organic vapors, not only due to its simplicity of operation in the field but, also, its simplifying the sample treatment, eliminating the use of extracting solvent, and increasing analytical sensitivity. Herein, the feasibility of applying DSTD in field conditions was assessed through a comparison of the results with those from the well-accepted active/charcoal method. Side-by-side active and diffusive (tube-type, Tenax TA as the adsorbent) samples, both personal and area, were collected and analyzed for xylenes, ethyl acetate, styrene, and n-butyl acetate in four different industrial settings. Statistically significant correlations were found between the two methods in personal samples with the correlation coefficients of 0.92, 0.90, 0.83, 0.88, and 0.97 for m&p-xylenes, o-xylene, n-butyl acetate, styrene, and ethyl acetate, respectively. A paired t-test revealed significant difference between the two methods for n-butyl acetate and styrene. For area sampling, statistical differences (p < 0.05) were found between the two methods, except for xylenes. The DSTD method had, mostly, a lower concentration than the active method, with the bias ranging from 10.2 to -54.4 percent. The possible causes for the discrepancies are discussed. These results suggest that though DSTD protocols can be considered as a simple approach for screening workers' exposures to volatile organics, they should be applied with caution since diffusive sampling is potentially affected by various environmental conditions and adsorptive characteristics. [ABSTRACT FROM AUTHOR]