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This paper reviewed the history of the coupling relationship between land consolidation and urban-rural development in China since 1949. It found that, although land consolidation projects in non-integrated urban-rural development phases improved the quality and quantity of cultivated land, it did not improve the rural decline effectively before 2013 because it focused more on land issues and did not complement and stimulate urban and rural development. Comprehensive land consolidations in China are expected to operate as both a tool and a platform for the operation of a developmental policy that aims to promote rural vitalisation through the integration of urban-rural development. The case of Huai Town was analysed using a framework of Rural In Situ Urbanisation (RISU) through a semi socio-economic restructuring. This was done to present an innovative style of RISU in which villagers live in towns and their livelihoods, living spaces, and public services are urbanised while they still retain both their rural land rights and rural household registrations, which allowed for the integration of urban and rural resources, the protection of villagers' interests, and a smooth social transition. The key factors for these comprehensive land consolidations to help combat rural decline include a bottom-up, community-supported structure; a coordinated approach incorporating livelihood transformation, population urbanisation, and land urbanisation, with livelihood transformation serving as the foundation; and the protection of villagers' rights and interests. • Land consolidation projects before 2013 in China did not improve the rural decline effectively. • Comprehensive land consolidations in China are expected to operate as both a tool and a platform for the operation of a developmental policy that aims to promote rural vitalization. • The key factors for comprehensive land consolidations to help combat rural decline include a community-supported structure; a coordinated approach and the protection of villagers' rights. • The type of RISU in the case township achieved the integration of urban and rural elements to combat rural decline in which villagers who lived in small towns were still with rights to village land collective ownership. [ABSTRACT FROM AUTHOR]

The antimicrobial peptide APKGVQGPNG (named YD), a natural peptide originating from Bacillus amyloliquefaciens CBSYD1, exhibited excellent antibacterial and antioxidant properties in vitro. These characteristics are closely related to inflammatory responses which is the central trigger for liver fibrosis. However, the therapeutic effects of YD against hepatic fibrosis and the underlying mechanisms are rarely studied. In this study, we show that YD improved liver function and inhibited the progression of liver fibrosis by measuring the serum transaminase activity and the expression of α -smooth muscle actin and collagen I in carbon tetrachloride-induced mice. Then we found that YD inhibited the level of miR-155, which plays an important role in inflammation and liver fibrosis. Bioinformatics analysis and luciferase reporter assay indicate that Casp12 is a new target of miR-155. We demonstrate that YD significantly decreases the contents of inflammatory cytokines and suppresses the NF- κ B signaling pathway. Further studies show that transfection of the miR-155 mimic in RAW264.7 cells partially reversed the YD-mediated CASP12 upregulation, the downregulated levels of inflammatory cytokines, and the inactivation of the NF- κ B pathways. Collectively, our study indicates that YD reduces inflammation through the miR-155– Casp12 –NF- κ B axis during liver fibrosis and provides a promising therapeutic candidate for hepatic fibrosis. The antimicrobial peptide YD is beneficial for alleviating liver fibrosis. The inhibitory role of YD in inflammatory responses is mediated by the miR-155– Casp12 –NF- κ B axis. Image 1 [ABSTRACT FROM AUTHOR]

In this paper, an in situ technique for the localisation and the sizing of cracks in plate-like structures is presented. The excitation and the reception of the ultrasonic diagnostic signal – Lamb waves – are achieved by permanently installed piezoelectric ceramic disks. The technique simplifies the underdetermined problem of the full characterisation of cracks to an over-determined problem of the localisation of crack tips. Also, it overcomes the difficulties associated with using the pitch-catch excitation scheme for crack characterisation. The development of the technique was done systematically using analytic models and the finite element method. The technique has been validated by an experiment and assessed by extensive parametric studies. While it was designed to be a convenient approach, highly accurate crack characterisation has been attained as evident through the results of both numerical studies and physical experiments. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effect of diffusive vs. deeply trapped hydrogen is deduced by time-dependent evolution of mechanical properties for ferritic alloys using novel in-situ nanoindentation during backside continuous hydrogen supply. • A linear relationship between hardness increase and hydrogen ingress is observed in the initial stage, with a more pronounced hardening effect for higher content of the studied substitutional elements. • An increase in dislocation density due to hydrogen is quantified by transmission electron microscopy. • Our data support the interpretation that hydrogen facilitates dislocation nucleation in the initial stage following the defactant theory; and we link the hardness increase to the dislocation density and friction stresses arising from diffusible hydrogen. Hydrogen embrittlement is common in metallic materials and a critical issue in industries involving hydrogen-related processes. Here we investigate the mechanical response upon hydrogen loading of ferritic Fe-16Cr, Fe-21Cr and Fe-4Al alloys. We use a novel in situ setup for electrochemical backside hydrogen charging during nanoindentation. Single-phase ferritic Fe-Cr binary alloys with high hydrogen diffusivity and low solubility, are ideal for in situ studies during hydrogen charging, particularly the effect of diffusible and lightly trapped hydrogen is targeted. The hardness increases linearly with increasing hydrogen content until a quasi-equilibrium state between hydrogen absorption and desorption is reached while Young's modulus remains unaffected. Above this transient region, the slope of the absolute hardness experiences a drastic decrease. The hardness variation in Fe-21Cr is anisotropic as determined for (1 0 0), (1 1 0) and (1 1 1) oriented grains. Increasing the Cr content enhances the hardening effect in (1 0 0) orientation: a 16.7 % hardness increase is observed in Fe-21Cr, while Fe-16Cr, shows an increment of 10.8 %. A Fe-4Al alloy increases slightly in hardness by only 4.3 % at the applied current density of 3 mA/cm2. The hardening effect is caused by enhancing dislocation density, as revealed by studying the cross-section underneath the nanoindentation imprints. [ABSTRACT FROM AUTHOR]

This paper explores the historical transformation of the rural education system and the mapping of rural schools in ancient, modern and contemporary China to explain the problems of the Rural School Mapping Adjustment (RSMA) policy. The value and purpose of the rural basic education system and school mapping adjustment are “urban priority and urban oriented”, which is the fundamental reason for the failure of the RSMA. A diachronic study of the history of China’s urban-rural relationship indicates that the relationship of traditional China’s urban-rural education was a virtuous cycle in which the city and the countryside were completely equal and reinforced each other. The promotion of modern education in the late Qing Dynasty severely undermined that virtuous cycle, leading to an urban-oriented rural education and the destruction of traditional values and a loss of the traditional ways of teaching. Although China has attempted to reduce the disparity between cities and the countryside by increasing the public financial investment in rural basic education after achieving a universal basic education, our case study in a village in North China demonstrates that the urban-oriented school mapping adjustment takes a toll on the rural area and exacerbates the problem of educational inequality, which actually increases the gap between urban and rural areas and between the rich and the poor. The conclusion is reached that the Chinese government should strive to develop a rural-oriented and rights-based rural basic education system and school mapping adjustment. [ABSTRACT FROM AUTHOR]

Abstract: We report on an investigation of a periodic diffractive Si grating structure used to enhance the absorption in thin film Si cells with an active layer 2μm by modelling. The media of the grating can be air (n=1.0) with detached back reflector or coated with a layer of dielectric material, SiO2 (n=1.4) as a buffering layer. Gratings with periods of 500, 800 and 1200nm were located on the rear side of the cell, with depths from 150nm to 300nm. The reason to use a shallow grating depth is to ensure smallest material loss. The influence of the grating period, depth and surrounding media on the short circuit was investigated and the optimal grating parameters were obtained. A structure which has a 500nm period, 150nm depth, in air media gives the best light trapping, with 76.5% enhancement of short current density (Jsc). [Copyright &y& Elsevier]

Non-destructive evaluation (NDE) techniques are widely used to detect and characterize different defects in engineering structures. However, the highly sensitive real-time quantitative imaging of irregularly shaped defects in large-area metallic structures remains challenging if conventional NDE approaches are used. In this paper, a speckle interferometer with unlimited minimal shearing amount – based on a simple imaging setup without the need to tilt any optical components – is explored for the application of detection and characterization of complex-shaped defects in metallic plates. This technology is able to directly yield strain measurements, allowing the defects to be detected by identifying induced strain concentrations under stress loading. Acoustic waves are used as stress loading for this imaging system with the advantage of a deeper penetration depth and a larger area of inspection as compared to conventional loading methods, e.g. thermal loading. The spatial carrier technique is introduced to quantitatively reconstruct the phase distribution, which contains information of the strain measurement from a single recording. To achieve the near real-time imaging of defects with relative insensitivity against noise, the image pairs are continuously recorded and correlated using the sequential subtraction method. The performance of the imaging system was tested with experimental data. The results demonstrate that the imaging system can generate high-quality images to provide good detection and characterization properties regarding irregularly shaped notches as well as accurate sizing of different notch dimensions. This work introduces a promising practical NDE tool for the near real-time, non-contacting and quantitative detection of subsurface defects with complex geometries in large-area metallic structures. • NDE application of SUCPSI is suitable for large area and near real-time inspection. • Acoustic wave excitation has the advantages of deep penetration depth, large area inspection and tunable driving frequency. • The sequential subtraction is first introduced to SUCPSI and appears better suited for on-line testing. [ABSTRACT FROM AUTHOR]

Ultrasonic techniques have been proved to be useful for detection and characterization of flaws in solid structures. However, it remains challenging to characterize flaws that do not have regular shapes. In this paper, an ultrasonic imaging technique based on elastic reverse time migration (ERTM) is developed for imaging notches with irregular shapes. In this method, the image is generated by cross-correlating the forward propagated wavefield from the source with the time-reversed backward propagated wavefield from the scatterer. Comparing to traditional ultrasonic imaging methods based on the travel time of ultrasonic signals, this method considers full waveforms which contain the information of mode conversions and multiple scattering, and therefore enables the possibility to image flaws with complex shapes. In this paper, the ERTM algorithm is applied to image a branched surface-breaking notch and an embedded stepped notch, showing excellent reconstruction results in both simulations and experiments. [ABSTRACT FROM AUTHOR]

• Cleavage fracture occurs after significant plastic deformation at room temperature in an advanced high strength steel (Q&P steel) with superior tensile properties. • Different failure patterns under sheet metal forming conditions are demonstrated using three types of advanced high strength steels. • The forming limit framework is extended to account for cleavage fracture, which is revealed to be relevant for metal forming of high strength materials. • A sensitivity analysis on failure patterns concerning material properties and stress state is performed to provide insights into developing high strength metallic materials. • The proposed framework provides a comprehensive guide for forming of various types of sheets. The forming limits and failure properties of three distinct advanced high-strength steels (AHSS) have been investigated under various stress states in tensile tests with optimized specimen geometries. In addition to the commonly observed failure patterns governed by localized necking and ductile fracture for two of the AHSS, after substantial plastic deformation at room temperature, cleavage fracture occurs for a large range of stress states in a laboratory quenching and partitioning steel with superior tensile properties. The competition between failure patterns, encompassing ductile and cleavage fractures with and without necking, is governed by the mechanical properties of materials and the stress states, as a transition of failure mechanisms occurs with increasing triaxiality. The forming limit framework is, therefore, further extended to seamlessly integrate cleavage fracture in this study, where the competition between various failure mechanisms is demonstrated using three AHSS in the space of critical strain and principal stress. These findings shed light on the importance of considering cleavage fracture strength as a parameter besides the strength-ductility synergy in advanced high-strength metallic materials, and the proposed framework also gives a more comprehensive guide in designing and conducting the sheet metal forming processes. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract In multiphase alloys, the mechanical properties are controlled by both the local properties of individual microstructural constituents, as well as the mutual effect of these constituents as an aggregate. To this end, we systematically studied the local mechanical properties and deformation mechanisms of the microstructural constituents in a ZnAl4Cu1Mg0.31 alloy using nanoindentation tests at room temperature (25 °C) and 85 °C. The obtained strain rate sensitivity and activation volume suggest dislocation-dominated deformation in the primary η-Zn phase and grain/phase boundary sliding in the eutectoid structures. Further, the strain partitioning between individual microstructural constituents and their roles on macroscopic deformation at 85 °C was investigated using quasi in-situ digital image correlation (DIC), supplemented with non-rigid image registration. The DIC measurements showed that eutectic and eutectoid colonies carry higher strain than the primary η-Zn phase grains. The presented approaches and results can therefore be used to design new Zn-Al alloys and also other multiphase alloys with improved mechanical properties. Graphical abstract Unlabelled Image Highlights • Nanoindentation is used to investigate the deformation of individual phases in a complex microstructure. • High resolution strain partitioning in multiphase alloys is obtained by digital image correlation and electron microscopy. • A new non-rigid image registration method to study the local strain partitioning is proposed. [ABSTRACT FROM AUTHOR]

Hepatic adverse reaction associated with Polygoni Multiflori Radix (PMR) has been frequently reported in recent years. Highly-enriched anthraquinones (AQs) in PMR, such as emodin, chrysophanol and physcion, have been found to be hepatotoxic. In the present study, sandwich-cultured rat hepatocytes (SCRHs) were employed to investigate the effect of individual and combined AQs on the disposition of endogenous bile acids (BAs) and exogenous probe substrates including deuterium-labeled taurocholate ( d 5 -TCA), glycochenodeoxycholic acid ( d 4 -GCDCA) and 5 (and 6)-carboxy-2′,7′-dichlorofluorescein (CDF). Emodin and chrysophanol significantly inhibited bile salt export pump and multidrug resistance-associated protein 2 (Mrp2), respectively, as evidenced by decreased biliary excretion index (BEI) of d 5 -TCA and CDF. Moreover, basolateral efflux transporters were inhibited by all individual and combined AQs. As a result, cellular accumulation of total and specific endogenous BAs were significantly elevated by individual AQs, alone or combined. In addition, down-regulation of Mrps in both gene and protein levels by AQs served as another critical contributing factor for BA accumulation in SCRHs. To be noted, subsequent adaptive gene regulation, including reduced Ntcp expression, upregulated Bsep levels, and downregulated Cyp8b1, alleviated, to a certain extent, but not prevented from toxic BA accumulation. In summary, all three AQs of interest are likely to alter BA disposition through direct inhibition of BA transporters as well as regulated expression of BA transporters and enzymes. [ABSTRACT FROM AUTHOR]

A silicon nanostructure is fabricated in polycrystalline silicon thin films by metal-assisted wet chemical etching using thermally annealed silver nanoparticles as a catalyst. The Si nanostructure has an ant-nest feature. Solar cells based on the silicon nanostructure gives 90% short-circuit current enhancement compared to the cells based on the planar film. We also report that Al 2 O 3 passivation of the silicon nanostructure provides a new approach to improving the polycrystalline silicon thin film’s electrical property. The open-circuit voltage of the Al 2 O 3 passivated cells is improved by 70 mV. [ABSTRACT FROM AUTHOR]

[Display omitted] The design of high performance structural materials is always pursuing combinations of excellent yet often mutually exclusive properties such as mechanical strength, ductility and thermal stability. Although crystal-glass composite alloys provide better ductility compared to fully amorphous alloys, their thermal stability is poor, due to heterogeneous nucleation at the crystal-glass interface. Here we present a new strategy to develop thermally stable, ultrastrong and deformable crystal-glass nanocomposites through a thermodynamically guided alloy design approach, which mimics the mutual stabilization principle known from symbiotic ecosystems. We realized this in form of a model Cr-Co-Ni (crystalline)/Ti-Zr-Nb-Hf-Cr-Co-Ni (amorphous) laminate composite alloy. The symbiotic alloy has an ultrahigh compressive yield strength of 3.6 GPa and large homogeneous deformation of ∼15% strain at ambient temperature, values which surpass those of conventional metallic glasses and nanolaminate alloys. Furthermore, the alloy exhibits ∼200 K higher crystallization temperature (T X > 973 K) compared to that of the original TiZrNbHf-based amorphous phase. The elemental partitioning among adjacent amorphous and crystalline phases leads to their mutual thermodynamic and mechanical stabilization, opening up a new symbiotic approach for stable, strong and ductile materials. [ABSTRACT FROM AUTHOR]

The evolution of Staphylococcus aureus (S. aureus) with the ability to acquire and develop resistance to antibiotics has been described as a distinct strain emergence event. Methicillin-resistant S. aureus (MRSA) is responsible for most global S. aureus bacteremia cases. Bacterial biofilms are one of the primary reasons for drug resistance. Biofilms formed by S. aureus are the most common cause of biofilm-associated infections, which increase the difficulty of treatment. Antimicrobial peptides (AMPs) represent promising candidates for the future treatment of antibiotic-resistant bacterial and biofilm-associated infections. In this study, we designed and synthesized a series of analogs to increase the druggability of the natural antimicrobial peptide CPF-C1. Among the analogs, CPF-2 showed high antimicrobial activity against MRSA and multidrug-resistant S. aureus isolated from clinics. In the serum and physiological salt environment, CPF-2 also exhibited effective antimicrobial activity. Importantly, CPF-2 did not determine resistance and showed no hemolytic activity at the active concentration. Concerning the mechanism of action, CPF-2 produced a rapid bactericidal effect by interrupting the bacterial membranes. Even more surprisingly, CPF-2 showed an excellent ability to prevent and eradicate biofilms caused by S. aureus and MRSA not only in vitro but also in vivo. Our results suggested that CPF-2 has potential as a lead compound to treat infections caused by S. aureus and MRSA, including the associated biofilms. • In order to improve the druggability of the natural antimicrobial peptide CPF-C1, we designed a series of analogs by amino acid substitution. • CPF-2, the analog of substituted by D-basic amino acids and D-hydrophobic amino acids, showed effective antimicrobial and antibiofilm activities against drug-resistant Staphylococcus aureus including MRSA both in vitro and in vivo. • The mechanism of action showed that CPF-2 produced a rapid bactericidal effect by interrupting the bacterial membranes. [ABSTRACT FROM AUTHOR]

Despite the demonstrated effectiveness of methods based on local defect resonance (LDR) in defect identification and sizing, the precision of LDR prediction is limited owing to the inconsistency between the fundamental assumption of existing methods and the reality. To tackle this deficiency, an analytical framework to interpret the formation of LDR induced by defects in multilayered structures is proposed. In this framework, reflections of Lamb waves at defect boundaries are investigated analytically, whereby the phase shift of reflected waves at defect boundaries is obtained. On this basis, the resonance formation is analyzed from a perspective of wave propagation and superposition, and the relation between the LDR frequency components and the defect size is ascertained. Experimental validations are performed in which LDR generated by defects in adhesively bonded multilayer structure are measured. This investigation provides an analytical insight into the defect-induced LDR and improves the precision of quantitative characterization of defects using LDR. • an interpretation of the formation of local defect resonance. • a new approach to analyze the interaction between GUWs and disbond in multilayered structures. • improved precision in prediction of local defect resonance frequencies. • demonstrated capability of accurately characterizing disbond defect. [ABSTRACT FROM AUTHOR]

Polyethylene pipe reinforced by winding steel wires (PSP) has been widely used in many industrial areas. Understanding the relationship between the burst pressure of PSP and the varying environmental temperature is necessary because the mechanical properties of high-density polyethylene (HDPE) significantly vary at different environmental temperatures. In this study, a method based on classical laminated-plate theory was developed to predict the short-term burst pressure of PSP under various temperatures. HDPE uniaxial tensile tests were conducted under various temperatures to obtain different elastic HDPE moduli at different temperatures. The varied mechanical properties of the matrix HDPE were considered to result in the variation of PSP properties. Theoretical results of PSP burst pressure was determined by substituting the varied HDPE properties into the analysis model. Short-term PSP burst tests were conducted under various temperatures to validate the proposed method. The theoretical results agreed well with test results, with relative error ranging from 6.72% to 8.82%. The cause of errors was analyzed. Furthermore, the load carrying capacity of PSP was analyzed and discussed in detail based on the PSP analysis model. [ABSTRACT FROM AUTHOR]

Abstract: We conducted a long-term restoration experiment in the degraded ecosystems of a semi-humid evergreen broadleaf forest in Muding County, Yunan Province, China. We used single-indicator assessment and our newly established comprehensive assessment model to compare the effects of four types of management (different historical disturbances+restoration measures) on forest restoration based on a vegetation survey. (1) Species richness in each of the four restoring communities was still lower than that of the zonal forest. There was a compensatory effect of species richness among different layers within communities. Restoration management by natural succession was clearly efficient at restoring species richness and composition, but the effect of disturbance history was minor. Human-assisted restoration had a great effect on biomass accumulation and model tree growth. Plant density was also affected by the different management types, which progressively led to differences in model tree growth and biomass accumulation. (2) The comprehensive assessment model, a simple method based on the restoration mechanism, can precisely quantify the overall restoration of ecosystems, historical disturbance and actual disturbance, using only one set of data. Restoration index (R d ), turning-point restoration index (R 0), restoration-effect index (R a ), turning-point disturbance index (D 0), actual disturbance index (D r ) and overcoming disturbance index (D a ) presented gradual changes in the four restoring communities. The combined single-indicator and comprehensive model method fully assessed the restoration of degraded ecosystems in a semi-humid evergreen broadleaf forest. [Copyright &y& Elsevier]

Renal fibrosis is a progressive disease that leads to renal dysfunction and end-stage renal failure, and there is currently no specific treatment. Our previous study showed that the 8-residue peptide DR8 (DHNNPQIR) exhibits potent antioxidant and antifibrotic properties, and accumulating evidence suggests that oxidative stress contributes greatly to fibrosis. The effects and mechanisms of DR8 on renal fibrosis remain unknown. The effects of DR8 were assessed in a unilateral ureteral obstruction mouse model that received a daily, single-dose subcutaneous injection of 500 μg/kg DR8 for 14 days and in cultured cells (HK-2 and NIH-3T3 cells) treated with 5 ng/mL TGF-β1 and 80 μM DR8. Western blotting, immunohistochemical staining, real-time qPCR and other tools were conducted to study the molecular mechanisms underlying antifibrotic effects. DR8 improved renal function and reduced injury and extracellular matrix (ECM) deposition. Inflammation and oxidative stress were alleviated by DR8 in vivo. DR8 also inhibited the activation of fibroblasts and ECM deposition in HK-2 and NIH-3T3 cells induced by TGF-β1. In addition, epithelial-to-mesenchymal transition (EMT) was inhibited by DR8 both in vivo and in vitro. Mechanistic studies supported that DR8 inhibited ERK and p38 mitogen-activated protein kinase (MAPK) activation. These results indicate that DR8 attenuates renal fibrosis via suppression of EMT by antagonizing the MAPK pathway. We provide mechanistic details for a potential therapeutic agent and establish a foundation for peptide therapeutics. Unlabelled Image [ABSTRACT FROM AUTHOR]