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Various industrial waste binders (IWBs) are being recycled in soil stabilization to save cement consumption. However, the coupled effects brought out by combined IWBs on stabilized soils are still unclear. IWBs are categorized into two typical categories (IWB-A and IWB-B) referring to their chemical role in this study. The alkali-source effect, pore-filling effect and cementation damage effect by IWBs in soil stabilization are explored. A series of mechanical and microscopic tests is performed on stabilized clay with different proportions of IWB-A and IWB-B. Moreover, initial water contents and cement contents of cement-stabilized clay are varied to examine the evolution of coupled effect with void ratio and cementation level. The results indicate that the alkali-source effect strengthens the cementation bonds and increases the early strength by 0.5–1.3 times, whereas the pore-filling effect improves the microfabric especially for the specimen with a large void ratio. The alkali-source effect increases soil cohesion cu at the pre-yield stage, and the pore-filling effect increases frictional angle φu at the post-yield stage. The cementation damage effect is remarkable at a low void ratio, which may result in many extruded pores among soil aggregates. The strength evolution with IWB proportions can be well stimulated by considering the coupled alkali-source effect, pore-filling effect and cementation damage effect. The optimal proportion of IWBs corresponds to an optimal combination of coupled effect.

BackgroundIt is common for older adults to move to urban communities after retirement, living with their adult children and caring for grandchildren in China. This impacts their social networks and, consequently, their psychological and physical health. However, research on proactive ways to mitigate the negative effects of social dislocation is lacking. This study examined how dancing with care (DWC), a new form of preventative care, promotes social integration among older adults in Chinese communities, focusing specifically on participants’ experiences related to community engagement, mutual support, volunteer activity, social connections, and advanced learning through their involvement with DWC.MethodsSemi-structured interviews were conducted with 60 older adults who regularly participated in DWC in communities in southern China.ResultsDWC’s dimensions play a vital role in addressing the social integration of older adults. Through DWC, older adults participate in community activities, engage in mutual support, volunteer in various activities, develop social connections, and learn different things, including the use of advanced technologies.ConclusionDWC addresses older people’s social integration by providing opportunities to be involved in the community. It provides a promising path for older adults to actively engage in the revival of social capital within their social networks in the community. This study offers valuable insights for enhancing social involvement for older adults.

To utilize discarded shield residue and alleviate the shortage of subgrade filling, industrial wastes such as calcium carbide slag (CCS) and fly ash (FA) were considered to enhance the mechanical properties of the shield residue. A series of laboratory tests, including California Bearing Ratio (CBR) tests, unconfined compressive strength (UCS) tests, moisture content tests, pH tests, water stability tests, and dry-wet cycles tests were performed on discarded shield residue with additive contents. The results show that the UCS and CBR values enhanced significantly with the increase in curing time. However, the moisture content and pH of the stabilized soil exhibited a decreasing trend. The early UCS of CCS-FA stabilized soil is slightly lower than that of QL-FA stabilized soil. After 60 curing days, all stabilized soil exhibited a UCS value exceeding 1.9 MPa. In addition, the CBR values of CCS-FA stabilized soil were more than 8 times higher than those of the original shield residue. Furthermore, the water stability of CCS-FA stabilized soil is slightly better than QL-FA stabilized soil, especially at 7 days and 14 days. As for dry-wet cycles test, after the fifth cycle, the CCS-FA stabilized soil maintained overall integrity. The CCS can effectively replace QL to enhance the mechanical properties of shield residue as subgrade filling.

This article examines how a new form of preventative care provision—dancing with care (DWC)—promotes social inclusion among older women in China and explores whether DWC can be regarded as an effective way to address the challenges these older women face in improving their social inclusion and achieving a healthy lifestyle. Our study demonstrates that various dimensions of DWC play a vital role in addressing the difficulties these older women encounter in their struggle to end their own social exclusion: These dimensions include levels of happiness, social network involvement, access to social support in “preventative care terms”, and the role of own’s grandchildren as a means to social bonding. Various dimensions of DWC align with the concept of preventative care for older women in urban communities. Using semi-structured interviews in selected “DWC communities” located in southern China, this article demonstrates that DWC contributes to addressing older women’s social inclusion by providing preventative care. In addition, we also performed an empirical data analysis that included institutional regulations for DWC design and implementation, publications by DWC communities, and academic research focused on DWC communities. DWC proposes an appealing path for older women to actively engage with and within their community. Furthermore, it offers valuable insights into the potential of a new model of preventative care and our conclusions will serve as a reference for enhancing social involvement among older individuals globally.

With the advantage of programmable electromagnetic properties, Reconfigurable Intelligent Surfaces (RISs) have drawn wide attention from both industry and academia. RIS-assisted communication systems can promote huge wireless channel quality improvement and remarkable coverage enhancement. This paper proposes general pathloss model, radiation pattern and mirror beam effect of 1-bit RIS at sub-6 GHz band. Field trails have been carried out in outdoor and indoor deployment scenarios. The proposed model is validated through extensive simulations and field-trial measurements. In addition, an optimized RIS phase-shit design process for the mirror beam elimination is proposed and validated with simulations. The proposed theoretical model and measurement results can promote future research and application in RIS-assisted communications.

Subway tunnel construction often crosses existing railways, and the soil loss caused by shield construction will inevitably lead to deformation of the surrounding strata and uneven settlement of the adjacent railway tracks, but there are few studies on the existing railway deformation caused by double shield construction in soil–rock composite strata. In this paper, based on the field monitoring data, the deformation analysis of the railway under-crossed by double shield tunnel in soil–rock​ composite stratum was carried out, and the influence law of hard-layer ratio, tunnel burial depth and railway roadbed reinforcement on the railway track deformation was revealed by numerical simulation. Results show that the track settlement mainly occurred in the middle and late stages of the shield crossing the railway. The track settlement showed an obvious trend of decreasing with the increase of hard-layer ratio or tunnel buried depth. The roadbed reinforcement can significantly reduce the settlement of the railway track, the smaller the hard-layer ratio, the better the roadbed reinforcement effect.

A large number of mixed soils exist in nature, including sand–clay mixtures, silt–clay mixtures and clay–clay mixtures. The physical parameters of soils are the basis for investigating their mechanical properties (compression, permeability, strength). More importantly, the liquid limits play an important role in establishing the relationships between physical and mechanical properties. The liquid limit tests of sand–clay mixtures were performed on different kinds of original clays with different sand contents. These data together with those compiled from the literature were used to investigate the change in liquid limits of mixed soils. The results show that the liquid limits of mixed soils are influenced by the types of original soils and the contents of each constituent. In sand–clay mixtures, the liquid limits increase with the increasing clay contents. The empirical equation is proposed to predict the liquid limits of sand–clay mixtures based on the liquid limits of original clays and clay contents. By analogy, the method for predicting liquid limits of mixed soils including two types of original soils with known liquid limits is acquired, such as silt–clay mixtures and clay–clay​ mixtures. Such a method is also extrapolated to the mixed soils with more types of original soils.

Cement-based stabilization by deep mixing or grouting is a popular method used to enhance soft clay ground because clay gradation has a significant effect on its unconfined compression strength. However, the functional relationship between the gradation and the strength is currently unclear, which limits the assessment and cognition for the strength formation of cement-based stabilized soft clay. Strength experiments controlling the sand ratio were conducted, in addition to the literature review, to clarify the sand incorporation effect on the strength. An effective cement ratio (the mass ratio of cement to involved clay) was proposed to evaluate the strength of stabilized clay with sand incorporation. In order to combat data dispersion and the labour-intensive nature of these experiments, meso-mechanical numerical simulations were carried out by the finite element method. This served to enrich the data and clarify the mesoscopic mechanism. The numerical result indicates that the strength of stabilized clay at low sand incorporation ratio is mainly controlled by the strength of the cement-clay-water matrix, thus verifying the rationality of studying the effective cement ratio. Subsequently, the threshold sand ratio in the cement-clay-water matrix was discussed to optimize the stabilization of soft clay.

Abstract Qingke Pingchuan granules (QKPCG), a patented traditional Chinese medicine, clinically, are recommended for acute tracheobronchitis, cough, community‐acquired pneumonia, and other respiratory diseases. However, its potential protective effect and mechanism of action in acute lung injury (ALI) have not been explored. We aimed to explore the mechanisms underlying the protective role of QKPCG in ALI. The therapeutic efficacy of QKPCG was investigated in a lipopolysaccharide (LPS)‐induced ALI mouse model. Mice were divided into three groups, namely, the Control, LPS, and LPS + QKPCG groups. Mice in the LPS + QKPCG group were administered QKPCG intragastrically as a treatment once a day for a total of three days. QKPCG effectively increased survival and reduced lung injury in treated mice. It significantly reduced the LPS‐induced expression of interleukin (IL)‐6, tumor necrosis factor‐α (TNF‐α), IL‐1α, and IL‐1β. RNA‐sequencing followed by real‐time quantitative polymerase chain reaction validation suggested a critical role of the secretoglobin family 1A member 1 (Scgb1a1) gene in mediating the protective effect of QKPCG. Further, QKPCG reversed the LPS‐induced downregulation of the Clara cell 10 kDa protein (CC10), a pulmonary surfactant protein encoded by Scgb1a1, which is mainly secreted by club cells in the lungs. Exogenous supplementation of CC10 alleviated LPS‐induced ALI. Hematoxylin and eosin staining and enzyme‐linked immunosorbent assay results further confirmed the anti‐inflammatory properties of CC10, which were suggested as mediated via the inhibition of NFκB phosphorylation. In summary, our study provides evidence of the beneficial role of QKPCG in alleviating lung injury, mediated via the decreased disruption of club cells and higher expression of CC10, which leads to NFκB pathway inhibition.

A noncontact ECG is applicable to wearable bioelectricity acquisition because it can provide more comfort to the patient for long-term monitoring. However, the motion artifact is a significant source of noise in an ECG recording. Adaptive noise reduction is highly effective in suppressing motion artifact, usually through the use of external sensors, thus increasing the design complexity and cost. In this paper, a novel ECG electrode structure is designed to collect ECG data and reference data simultaneously. Combined with the adaptive filter, it effectively suppresses the motion artifact in the ECG acquisition. This method adds one more signal acquisition channel based on the single-channel ECG acquisition system to acquire the reference signal without introducing other sensors. Firstly, the design of the novel ECG electrode structure is introduced based on the principle of noise reduction. Secondly, a multichannel signal acquisition circuit system and ECG electrodes are implemented. Finally, experiments under normal walking conditions are carried out, and the performance is verified by the experiment results, which shows that the proposed design effectively suppresses motion artifacts and maintains the stability of the signal quality during the noncontact ECG acquisition. The signal-to-noise ratio of the ECG signal after noise reduction is 14 dB higher than that of the original ECG signal with the motion artifact.

This paper aims to study the shear behavior of binary particles with irregular shapes by discrete element method simulations of the biaxial test in the membrane boundary condition. Binary particle samples are generated according to different volume fractions of coarse and fine particles. The deviatoric stress and volumetric strain curves are plotted to describe the contracting-dilatancy relationship of binary samples under shearing conditions. The anisotropy of the normal and tangential contact forces are explored by visualization of the orientation of contact forces to describe the evolution of micro structures of samples during the shearing process. Besides, the formations of the shear band are observed by the visualization of the newly generated contact force chains between particles. The research shows that the volume fraction of coarse particles and particle size ratio have significant influences on the shear behavior of binary particles both in macroscopic and microscopic points of view. Moreover, the increased volume fraction of coarse particles leads to a more difficult formation of a shear band.

Interleukin-6 (IL-6) plays a crucial role in systemic autoimmunity and pathologic inflammation. Numerous studies have explored serum IL-6 levels in systemic lupus erythematosus (SLE) and their correlation with disease activity. Here, we performed a meta-analysis to quantitatively assess the correlation between the serum IL-6 levels and SLE activity. The PubMed and EMBASE databases were thoroughly searched for relevant studies up to September 2019. Standardized mean differences (SMDs) with 95% confidence intervals (95% CIs) were used to describe the differences between serum IL-6 levels in SLE patients and healthy controls and between those in active SLE patients and inactive SLE patients. The correlation between the serum IL-6 levels and disease activity was evaluated using Fisher’s z values. A total of 24 studies involving 1817 SLE patients and 874 healthy controls were included in this meta-analysis. Serum IL-6 levels were significantly higher in SLE patients than in the healthy controls (pooled SMD: 2.12, 95% CI: 1.21-3.03, Active SLE patients had higher serum IL-6 levels than inactive SLE patients (pooled SMD: 2.12, 95% CI: 1.21-3.03). Furthermore, the pooled Fisher’s z values (pooled Fisher’s z=0.36, 95% CI: 0.26-0.46, p4 was defined as active SLE. More homogeneous studies with large sample sizes are warranted to confirm our findings due to several limitations in our meta-analysis.

Consolidated undrained triaxial compression tests were performed to investigate the shear strength behavior of the solidified dredged materials (SDM). The variation law of deviator stress and excess pore water pressure with the increase of the applied confining pressure was investigated. It is found that the shear strength envelope is consisted of two lines, and there exists a transitional stress on the intersection point. The undrained shear strength develops slightly with the increase of applied normal stress in the preyield state. However, the undrained shear strength increases significantly in the postyield state, and the strength envelope is nearly a straight line with the extension through the origin. Based on the triaxial test data and the binary medium model, a strength criterion considering strength evolution mechanism is proposed and the relevant parameters of the strength criterion were discussed. Comparisons of the predicted results and experimental data demonstrate that the proposed strength criterion can properly describe the strength evolution rules of the SDM.

The impact of varying pressure, feed rate, and abrasive mass flow rate on the efficiency of an abrasive water jet cutting process was studied in this work. Recombinant bamboo samples with thicknesses of 5, 10, and 15 mm were cut by the abrasive water jet. The upper kerf width, lower kerf width, and the ratio of the upper kerf width to lower kerf width were chosen as the efficiency parameters. Mathematical models were developed to describe the relationship between the input process parameters and the efficiency parameters. The arrangement of experiments and analysis of results were performed based on response surface methodology. The evaluated model yielded predictions in agreement with experimental results.

The influence of rake angle, cutting speed, and uncut chip thickness on cutting forces and chip morphology in medium density fiberboards orthogonal cutting was investigated. With regard to the normal cutting force and the feed force recorded, there were important variations when machining conditions were modified, or when some tool characteristics were changed. The findings led to the conclusion that there was a close relationship between the cutting conditions and chip formations as well as the cutting forces. Such forces were found to be particularly sensitive to changes in uncut chip thickness, as well as showing dependence on the cutting speed of the tools in orthogonal cutting.

During chamber openings, the filter cake that has formed on the excavation face is thin and cannot be monitored directly, resulting in an unclear understanding of its destruction mechanism. To investigate the destruction mechanism of filter cake under air pressure, a series of air breakthrough tests (ABTs) were conducted in this study, during which the water discharge and pore pressure were monitored. The experimental results indicate that the filter cake undergoes significant compression during ABTs, but it tends to be stabilized after a testing time of 40,000 s. Cracks and pores are observed on the surface when the filter cake is destructed, and the cracks are mainly distributed between 80 and 100 % of the radius. The effective working time (EWT) of Filter Cake B with a compression time beyond 40,000 s is much longer than that of Filter Cake A with a compression time below 40,000 s. Because the EWT of Filter Cake B is much longer than that of Filter Cake A, the slurry composition that promotes the formation of Filter Cake B should be used as much as possible during the slurry shield. Additionally, it is proven that the EWT increases with higher slurry density and filter cake thickness, whereas it decreases with increasing slurry viscosity. The analysis of the filter cake destruction mechanism shows that the compression of filter cake, capillary effect, mechanical effect, and interfacial effect all play important roles in filter cake destruction. Except for the compression of the filter cake that can extend the EWT, the other effects will accelerate the filter cake destruction. [ABSTRACT FROM AUTHOR]