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Horizontal Directional Drilling (HDD) is an environment-friendly and high efficient method for underground utilities and pipelines crossing. The formation of cuttings bed, due to low Cuttings Transport Performance (CTP) in large-size HDD, has resulted in the overwear of reamer and been required additional borehole cleanups which will result in high construction risk and extending the work period. In order to investigate the formation and broken mechanism of cuttings bed, two tests were designed to determine the potential effect of mud rheological properties, flow rate, borehole inclination and rotation of drill rod on the cuttings bed state. The drill rod laid down at the invert of the borehole, broke the stability state of cuttings bed and take some cuttings away from the cuttings bed, which causes an incremental trend of CTP, even for the cuttings bed consisting of 8–12 mm diameter cuttings. The observations and results of the tests indicated that drill rod rotation had a positive impact on the instability of cuttings bed, whereas, YP of mud, average velocity of mud and borehole inclined shown a limited effect on it for the large-scale HDD reaming. Further study is needed to determine the details about drill rod behavior and extend the tests results by the finite element method. [ABSTRACT FROM AUTHOR]

Sclerostin, a potent soluble inhibitor of the Wnt signalling pathway, is known to inhibit bone formation by suppressing osteocytes differentiation and function. Patients with chronic kidney disease have high levels of serum sclerostin. Sclerostin has been implicated in the pathogenesis of vascular calcification, which may promote the cardiovascular events of morbidity and mortality in chronic kidney disease patients. However, the role of sclerostin in vascular calcification and clinical prognosis in chronic kidney disease remains elusive. While some studies suggested a positive correlation between serum sclerostin and vascular calcification or clinical outcome, other studies showed no or even negative correlation between them. Small sample size, heterogeneity in enrolled patients, discrepancy in anatomical structure examined and differences in the applied assays may be responsible for the discrepant results. Nonetheless, anti-sclerostin antibodies may be a new therapeutic approach to increase bone mass and strength in chronic kidney disease. This review aims to have a better understanding of the relationship of serum sclerostin with vascular calcification and clinical outcome in chronic kidney disease patients, and propose the application of anti-sclerostin therapy in chronic kidney disease. [ABSTRACT FROM AUTHOR]

Being one of the most productive China seas, the East China Sea is facing the challenge of unprecedented biodiversity loss and habitat degradation under the dual pressure of anthropogenic disturbance and climate change. Although marine protected areas (MPAs) are considered an effective conservation tool, it remains unclear whether existing MPAs adequately protect marine biodiversity. To investigate this issue, we first constructed a maximum entropy model to predict the distributions of 359 threatened species and identified its species richness hotspots in the East China Sea. Then we identified priority conservation areas (PCAs1) under different protection scenarios. Since the actual conservation in the East China Sea is far from the goals proposed by Convention on Biological Diversity, we calculated a more realistic conservation goal by quantifying the relationship between the percentage of protected areas in the East China Sea and the average proportion of habitats covered for all species. Finally, we mapped conservation gaps by comparing the PCAs under the proposed goal and existing MPAs. Our results showed that these threatened species were very heterogeneously distributed, and their abundance was highest at low latitudes and in nearshore areas. The identified PCAs were distributed mainly in nearshore areas, especially in the Yangtze River estuary and along the Taiwan Strait. Based on the current distribution of threatened species, we suggest a minimum conservation goal of 20.4% of the total area of the East China Sea. Only 8.8% of the recommended PCAs are currently within the existing MPAs. We recommend expanding the MPAs in six areas to achieve the minimum conservation target. Our findings provide a solid scientific reference and a reasonable short-term target for China to realize the vision of protecting 30% of its oceans by 2030. [Display omitted] • Existing MPAs inadequately protect marine biodiversity in the East China Sea. • Geographical distributions of 359 threatened species were predicted using MaxEnt. • Priority conservation areas were identified via systematic conservation planning. • A minimum conservation goal of 20.4% of the area of the East China Sea was suggested. • MPAs could be expanded in six key areas to achieve the minimum conservation target. [ABSTRACT FROM AUTHOR]

• Partially BRB with T-shaped double core (PTBRB) is proposed for seismic retrofit. • Cyclic tests conducted to examine seismic performance and failure modes of PTBRB. • Numerical analysis performed to identify the controlled buckling mode of PTBRB. • Theoretical local buckling capacity of PTBRB derived to achieve seismic fuse function. A novel partially buckling-restrained brace with T-shaped double core (PTBRB) was proposed for the seismic retrofit of existing T-shaped steel members consisting of two separated steel angles. The retrofitting scheme primarily comprises two external steel angles and one cover plate which are bolted to serve as restrainer to prevent global buckling of existing T-shaped steel members. Cyclic tests were performed to verify the effectiveness of the retrofitting scheme and evaluate the PTBRB performance as seismic fuse. The results showed that adoption of the retrofitting scheme had negligible influence on the elastic stiffness of the T-shaped steel members, but their axial compression force capacity was increased by 60 %. The PTBRB specimens exhibited full hysteresis before failure, with the best ductility coefficient and cumulative plastic deformation capacity of 11.83 and 523, respectively. The controlled buckling mode of the PTBRB was identified by numerical analysis, and the results showed that the local buckling of a single steel angle member was responsible for the stiffness degradation of the PTBRB hysteresis. Theoretical local stability analysis of PTBRB was carried out according to Bleich's theory and Lundquist's theory and the test results confirm that the Bleich's theory is more reliable for predicting the theoretical inelastic critical load. The maximum compression capacity of the PTBRB corresponding to the local stability requirement of a single steel angle member is proposed to achieve the seismic fuse function, which is further validated by numerical analysis. [ABSTRACT FROM AUTHOR]

• Across-fault ground motions were corrected, decomposed, scaled, and synthesized. • Seismic performance of fault-crossing cable-stayed bridge with damper system. • Conventional multi-criteria method was improved to optimize fault-crossing angle. • Damper system of fault-crossing cable-stayed bridge was optimized. • Damping effect of viscous damper system on fault-crossing bridge was investigated. Bridge structures across active faults suffer the serious threats from large surface deformation and velocity pulses. This study focuses on developing a multi-criteria optimizing method and investigating the damping effect of the optimized damper system on a cable-stayed bridge across a strike-slip fault. A simplified baseline corrected method is adopted to recover the static offsets in near-fault records and the improved record-decomposition incorporation method is modified to produce artificial across-fault ground motions. A single pylon cable-stayed bridge across a strike-slip fault is taken as the case bridge and the refined nonlinear numerical model is established in OpenSees. The conventional multi-criteria decision making (MCDM) theory is improved by introducing new function forms and a control parameter to assess the best fault-crossing angles of the case bridge. The improved MCDM method is integrated with the beetle antennae search algorithm to optimize the damper system of the case bridge. Finally, the influence of fault-crossing angles and earthquake parameters (permanent displacements and ratios of maximum to permanent displacement) on the damping effect of the optimized damper system are investigated. The results indicate that the cable-stayed bridge reaches optimal seismic performance when the fault-crossing angle is around 90° (75°-105°) as both the biaxial nonlinearity of the pylon and the risk of the girder unseating are reduced. The damper system is efficiently optimized by the proposed method, and the displacement and force demand of the case bridge are balanced. Both the fault-crossing angles and earthquake parameters are observed to have considerable influence on the damping effects. More specifically, the damping effect on most seismic responses is optimized when the fault-crossing angle approaches 90° (60°-120°). As the permanent displacement increases, the damping effect on the pier-girder relative displacement is significantly reduced and the damping effect on the pier moments is moderately decreased. Moreover, the damping effect is improved for all the seismic responses as the ratios of maximum to permanent displacements increase, with the exception of transverse displacement. [ABSTRACT FROM AUTHOR]

Plant invasion and increased flooding intensity projected by climate change models can change the soil capacity of marine wetland to store P. This is a key question to the nutrient balances and eutrophication processes of coastal areas, especially in China coastal area that is receiving the freshwaters of a country in fast economical developing process. We studied the impact of changes in flooding intensity and plant invasion on total soil-P concentrations in the Minjiang River estuarine wetland. Flooding had a weak positive effect on soil P-fractions concentrations, but this effect was largely counteracted by the negative effect of salinity. Soil clay concentration and pH, both of which were related more with species community composition than with flooding intensity, were directly related to the P-fraction concentrations. The replacement of the native mangrove community by the invasive plant Phragmites australis was related to a decrease in the soil capacity to store P. A suitable management to maintain this wetland area in optimum conditions to act as a natural eutrophication buffer should tend to favor mangrove communities in the new areas that reach more than 220 days y of flooding, and a combination of the three tall-grasses communities below this level of flooding. [ABSTRACT FROM AUTHOR]