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This paper presents an innovative method to include creep deformations in the prediction of time to corrosion-induced cover cracking. Using experimental results, creep and cracking criteria used in this method are verified. It is argued in the paper that the cover cracking problem under corrosion is close to a relaxation problem and the conventional creep formulations based on the effective elastic modulus cannot be adopted. It is found in the paper that accurate consideration of creep deformation would lead to about 30–40% longer time to cover cracking when compared to no consideration of creep deformations whilst for the currently practiced methods, the time can be up to 200% longer, which is unconservative in predicting time to cover cracking. Results in this paper open the debate on modelling of creep in the analysis of corrosion-affected structures and serve as an important step towards the accurate prediction of corrosion-induced concrete cracking.

The PIWI-interacting RNA (piRNA) pathway is an adaptive defense system wherein piRNAs guide PIWI family Argonaute proteins to recognize and silence ever-evolving selfish genetic elements and ensure genome integrity. Driven by this intensive host–pathogen arms race, the piRNA pathway and its targeted transposons have coevolved rapidly in a species-specific manner, but how the piRNA pathway adapts specifically to target silencing in mammals remains elusive. Here, we show that mouse MILI and human HILI piRNA-induced silencing complexes (piRISCs) bind and cleave targets more efficiently than their invertebrate counterparts from the sponge Ephydatia fluviatilis. The inherent functional differences comport with structural features identified by cryo-EM studies of piRISCs. In the absence of target, MILI and HILI piRISCs adopt a wider nucleic-acid-binding channel and display an extended prearranged piRNA seed as compared with EfPiwi piRISC, consistent with their ability to capture targets more efficiently than EfPiwi piRISC. In the presence of target, the seed gate—which enforces seed–target fidelity in microRNA RISC—adopts a relaxed state in mammalian piRISC, revealing how MILI and HILI tolerate seed–target mismatches to broaden the target spectrum. A vertebrate-specific lysine distorts the piRNA seed, shifting the trajectory of the piRNA–target duplex out of the central cleft and toward the PAZ lobe. Functional analyses reveal that this lysine promotes target binding and cleavage. Our study therefore provides a molecular basis for the piRNA targeting mechanism in mice and humans, and suggests that mammalian piRNA machinery can achieve broad target silencing using a limited supply of piRNA species.

Sporadic or late-onset Alzheimer’s disease (LOAD) accounts for more than 95% of Alzheimer’s disease (AD) cases without any family history. Although genome-wide association studies have identified associated risk genes and loci for LOAD, numerous studies suggest that many adverse environmental factors, such as social isolation, are associated with an increased risk of dementia. However, the underlying mechanisms of social isolation in AD progression remain elusive. In the current study, we found that 7 days of social isolation could trigger pattern separation impairments and presynaptic abnormalities of the mossy fibre-CA3 circuit in AD mice. We also revealed that social isolation disrupted histone acetylation and resulted in the downregulation of 2 dentate gyrus (DG)-enriched miRNAs, which simultaneously target reticulon 3 (RTN3), an endoplasmic reticulum protein that aggregates in presynaptic regions to disturb the formation of functional mossy fibre boutons (MFBs) by recruiting multiple mitochondrial and vesicle-related proteins. Interestingly, the aggregation of RTN3 also recruits the PP2A B subunits to suppress PP2A activity and induce tau hyperphosphorylation, which, in turn, further elevates RTN3 and forms a vicious cycle. Finally, using an artificial intelligence-assisted molecular docking approach, we determined that senktide, a selective agonist of neurokinin3 receptors (NK3R), could reduce the binding of RTN3 with its partners. Moreover, application of senktide in vivoeffectively restored DG circuit disorders in socially isolated AD mice. Taken together, our findings not only demonstrate the epigenetic regulatory mechanism underlying mossy fibre synaptic disorders orchestrated by social isolation and tau pathology but also reveal a novel potential therapeutic strategy for AD.

ABSTRACTWith increasing recognition of randomness and time-variance of variables in structural assessment, time-dependent reliability (TdR) methods have gained popularity among researchers and practitioners. This paper critically reviews commonly used TdR methods, with focuses on analytical solutions, hybrid solutions and simulation solutions. Through this review and analysis, research challenges for TdR methods are identified and future research directions are proposed. It is found that Rice formula-based solutions are accurate but have limited solutions, hybrid solutions are efficient but affected by non-Gaussianity and nonlinearity of limit state functions, and simulation solutions are robust but time-consuming for complex structure systems. It is also found that the effectiveness of TdR methods depends highly on the complexity of limit state functions and types of stochastic processes involved, in particular, the stationarity, Gaussianity and correlation. The contribution of this review is that different TdR methods are elucidated and future research directions are proposed.

In insect ionotropic γ-aminobutyric acid receptor (iGABAR) subunits, only resistance to dieldrin (RDL) can be individually and functionally expressed in vitro. In lepidopteran, two to three RDL subtypes are identified; however, their physiological roles have not been distinguished in vivo. In this study, SlRdl1 and SlRdl2 of S. liturawere individually knocked out using CRISPR/Cas9, respectively. The mortality and larval and pupal duration of KOSlRdl1 and KOSlRdl2 were increased. The flight time and distance were increased by 43.30%–80.66% and 58.96%–198.22%, respectively, in KOSlRdl1. The GABA-induced current was significantly decreased by 53.57%–74.28% and 46.91%–63.34% in the ventral nerve cord, and the GABA titer was significantly reduced by 17.65%–28.05% and 19.85%–42.46% in KOSlRdl1 and KOSlRdl2, respectively. In conclusion, SlRdl1 and SlRdl2 are necessary for the transmission of GABA-induced neural signals; however, only SlRdl1 could regulate the flight capability of S. litura. Our results provided a new avenue to study lepidopteran iGABARs.

To repair and protect ancient stone arch bridges from weathering, this paper proposed a comprehensive weathering prevention method. Based on the strategy of survey, diagnosis, analysis and therapy, the method consisted of four phases, including collecting digital records, performing weathering assessment, conducting laboratory analysis and choosing a conservation method, which could scientifically evaluate the weathering degree and provide a conservation method for stone arch bridges. The method was introduced via application to a typical ancient Chinese stone arch bridge, the Putang Bridge. Digital recording was mainly achieved through 3D scanning technology. Weathering assessment mainly depended on the weathering mapping method, and the analysis was divided considering the different parts of the bridge and the overall bridge, through which bridge weathering could be more precisely evaluated. Laboratory tests were conducted involving both weathered and fresh samples for degree comparison, including petrographic analysis, mercury intrusion porosimeter, X-ray diffraction and scanning electron microscopy. The conservation method was based on the optimum protective agent, and the tests of the protective agent included water absorption tests, durability tests, colour difference analysis tests and micro-mechanism observation tests. Finally, the bridge stones were determined as a type of tuff stone, the linear damage index of the overall bridge was 2.21, and the progressive damage index was 2.46. Regarding the different parts of the stone arch bridge, the most easily damaged parts included the balustrades, parapets, cutwater stones and foundations. After the tests, a type of oil-borne silicon- and resin-based protective agent was determined as the optimum one for this stone bridge. The research results could provide a scientific basis and operational guidance for weathering prevention of ancient stone arch bridges.

AbstractThe material properties and bond-slip behaviour of the reinforced concrete beams during the period of the Republic of China (1912–1949) are different from those of modern reinforced concrete beams, so it is necessary to study the calculation method of the shear capacity of this type of beams. First, the material properties of the concrete and the square rebar, the bond-slip behaviour, and the failure mechanism of the beams were obtained in the tests by using square rebar during the period of the Republic of China(ROC) and concrete with the mix proportions of the ROC period. The results show that the ROC beam had a critical crack that propagates to the upper surface of the beam causing the beam failure. Then, a modified arch-truss model was proposed to quantitatively evaluate the relationship between the critical crack propagating process and the shear value, which is in good agreement with the test results. Finally, based on the calculation results of the modified model, a simplified trilinear model was proposed to determine the critical height of diagonal crack propagation in ROC reinforced concrete beams. The research results can provide a scientific basis for the shear capacity calculation and conservation of ROC reinforced concrete beams.

ABSTRACTConsidering safety and serviceability simultaneously, a comprehensive system limit state function (LSF) model and its application for CRTS II track slab is analyzed. First, a comprehensive system LSF model is proposed, and the procedure of comprehensive system reliability analysis is developed from integrating the method of moments with finite element (FE) code. Second, based on the proposed model, comprehensive system LSF of CRTS II track slab is constructed, considering five important safety failure modes and three important serviceability failure modes. Then, comprehensive system reliability of a CRTS II track slab on simply supported viaduct is analyzed using the proposed method, and the result is compared with general system reliabilities considering safety and serviceability separately. It is found that the proposed comprehensive system LSF model has a flexible form and the proposed methodology can be efficiently applied for comprehensive system reliability assessment. It is also found that comprehensive system reliability analysis is more appropriate compared with general system reliability analysis, and thus, comprehensive system reliability results can help to determine an appropriate maintenance strategy and ensure the safety operation for high-speed trains.

ABSTRACTThe roof configurations of traditional Chinese timber buildings are unique and noticeably different from those of modern buildings, and their roof waterproofing performance is typically very poor. To improve their waterproofing performance, a new adaptive waterproofing membrane was developed and examined. First, typical roof configurations of traditional Chinese timber buildings were investigated and categorized. Then, finite element models of four typical roofs were established in ANSYS, and the stress distributions at the interfaces between the waterproofing membrane layer and adjacent roof layers were studied. Finally, a new adaptive roof waterproofing membrane for traditional Chinese timber buildings was developed, and relevant experiments on its material properties and mechanical performance were carried out. The properties of the new membrane were compared with those of ethylene propylene diene monomer, styrene-butadiene-styrene and atactic polypropylene waterproofing membranes. The results showed that the new waterproofing membrane has very good material properties and can meet the structural safety requirements for the roofs of traditional Chinese timber buildings. This membrane may also provide an adaptive conservation solution for such buildings and can substantially improve the waterproofing performance and durability.

The dynamic three-dimensional structures of chromatin and extrachromosomal DNA molecules regulate fundamental cellular processes and beyond. However, the visualization of specific DNA sequences in live cells, especially nonrepetitive sequences accounting for most of the genome, is still vastly challenging. Here, we introduce a robust CRISPR-mediated fluorescence in situ hybridization amplifier(CRISPR FISHer) system, which exploits engineered sgRNA and protein trimerization domain-mediated, phase separation-based exponential assembly of fluorescent proteins in the CRISPR-targeting locus, conferring enhancements in both local brightness and signal-to-background ratio and thus achieving single sgRNA-directed visualization of native nonrepetitive DNA loci in live cells. In one application, by labeling and tracking the broken ends of chromosomal fragments, CRISPR FISHer enables real-time visualization of the entire process of chromosome breakage, separation, and subsequent intra- or inter-chromosomal ends rejoining in a single live cell. Furthermore, CRISPR FISHer allows the movement of small extrachromosomal circular DNAs (eccDNAs) and invading DNAs to be recorded, revealing substantial differences in dynamic behaviors between chromosomal and extrachromosomal loci. With the potential to track any specified self or non-self DNA sequences, CRISPR FISHer dramatically broadens the scope of live-cell imaging in biological events and for biomedical diagnoses.

Broflanilide, a novel meta-diamide insecticide, has been registered worldwide to control agricultural pests, and cause negative influence to insects under not only lethal but also sublethal levels in the field. Fall armyworm (FAW), Spodoptera frugiperda, is a worldwide distributed insect frequently controlled by using insecticides. The molecular mechanisms by which broflanilide acts have yet to be fully characterized. In the present study, we exposed FAW larvae to sublethal dose (LD5), low lethal doses (LD10 and LD30) and median lethal dose (LD50) of broflanilide and measured various subsequent physiological sublethal effects. FAW larvae body length became shorter (LD5-LD50), the larvae and pupae duration were increased by 0.96-4.63 days (LD5-LD50), and the juvenile hormone (JH) titer significantly increased up to 134.46% (LD10-LD30). Meanwhile, the JH acid methyltransferase (JHAMT) and farnesyl diphosphate synthase 1 (FPPS1), which are critical enzymes of JH biosynthesis, respectively increased by 2.07- and 2.18- fold in the LD10 broflanilide-treated group, and by 2.22- and 1.78- fold in LD30 broflanilide-treated group in 3rd day larvae of FAW. In the 12-hour-old adults, SfrFPPS1 increased to 1.92-fold in the LD30 broflanilide-treated group. Broflanilide induced multiple physiological sublethal effects on the biosynthesis of JH by regulating the expression of SfrFPPS and SfrJHAMT genes in FAW and likely in other insects (both pests and non-target organisms). Therefore, its potential for Integrated Pest Management should be further assessed.

Aging is characterized with a progressive decline in many cognitive functions, including behavioral flexibility, an important ability to respond appropriately to changing environmental contingencies. However, the underlying mechanisms of impaired behavioral flexibility in aging are not clear. In this study, we reported that necroptosis-induced reduction of neuronal activity in the basolateral amygdala (BLA) plays an important role in behavioral inflexibility in 5-month-old mice of the senescence-accelerated mice prone-8 (SAMP8) line, a well-established model with age-related phenotypes. Application of Nec-1s, a specific inhibitor of necroptosis, reversed the impairment of behavioral flexibility in SAMP8 mice. We further observed that the loss of glycogen synthase kinase 3α (GSK-3α) was strongly correlated with necroptosis in the BLA of aged mice and the amygdala of aged cynomolgus monkeys (Macaca fascicularis). Moreover, genetic deletion or knockdown of GSK-3α led to the activation of necroptosis and impaired behavioral flexibility in wild-type mice, while the restoration of GSK-3α expression in the BLA arrested necroptosis and behavioral inflexibility in aged mice. We further observed that GSK-3α loss resulted in the activation of mTORC1 signaling to promote RIPK3-dependent necroptosis. Importantly, we discovered that social isolation, a prevalent phenomenon in aged people, facilitated necroptosis and behavioral inflexibility in 4-month-old SAMP8 mice. Overall, our study not only revealed the molecular mechanisms of the dysfunction of behavioral flexibility in aged people but also identified a critical lifestyle risk factor and a possible intervention strategy.

ABSTRACTSquare-rebars have been used in many historical reinforced concrete buildings worldwide. The durability and structural behavior of such historical buildings should be evaluated regularly and accurately. The prediction of the corrosion-induced cracking time is a critical element for the durability evaluation work. This study demonstrates a mathematical model for the corrosion-induced cover cracking for square-rebars and its time prediction method. The research methodology includes theoretical derivation and experimental validation. First, a simplified model that describes the corrosion-induced cover cracking for square-rebars is proposed, and then, Faraday’s law is combined with the model to develop a time prediction model for corrosion-induced cover cracking. Finally, an accelerated corrosion experiment for square-rebars is performed to validate the applicability and accuracy of the prediction model.

ABSTRACTTo strengthen its power and resist aggression, the Qing-dynasty government of China began building military-industrial bases after the Opium Wars and to learn advanced Western science and technology. Through nearly 150 years’ development, the former site of Jinling Arsenal has become the largest and most representative architectural group of modern military industrial heritage buildings in China. This paper analyzes the history and heritage characteristics of the site. It is found that under the exchanges and conflicts between Chinese and Western civilizations, the military architectural heritages reflect remarkable characteristics of pioneering and integration of Chinese and Western architectural styles, spatial forms and construction technologies, as well as the intrinsic traits of mixing and transition of structure, based on guiding ideology of “Chinese essence and Western utility”. These heritages not only show the influence and restriction of political goal on construction technologies, but also become the identity representation of the country, city and proprietors, thus having unique meaning and value. In addition, the corresponding methods and strategies, repair techniques and existing problems are discussed through the critical analysis of the conservation and adaptive reuse of typical heritage buildings, so as to provide basis and beneficial reference for related research and practice.

AbstractThis paper explicates an efficient quantitative evaluation method to shed light on the structural safety status of Chinese traditional hall-style timber buildings and to provide a scientific basis for their proper conservation. Firstly, a reducing elastic modulus method for calculating the importance of the components in Chinese traditional timber buildings is developed based on the change rate of the overall strain energy per volume. Compared with the conventional deleting element method, the reducing elastic modulus method is more suitable for Chinese traditional timber buildings. Secondly, through an on-site investigation and structural analysis of a typical case, the main hall of Baoguo Temple, both the obvious damage and the hidden damage of the hall-style timber building are studied and evaluated. Finally, based on the modified analytic hierarchy process (AHP) method considering the component importance, this paper proposes a proper evaluation system, evaluation indexes and index weights of the structural safety status, leading to an efficient quantitative evaluation method for the structural safety status of traditional timber buildings. The results can provide a basis for the preventive conservation of Chinese traditional hall-style timber buildings.

The durability of post-tensioned concrete (PTC) bridge structures has been greatly threatened by the corrosion of steel strands, especially in the case of insufficient grouting. In this paper, the effect of grouting quality on flexural behavior of corroded post-tensioned concrete (CPTC) beams is experimentally investigated with two groups of T-beams, i.e., five fully grouted beams in Group A and five partially grouted beams in Group B. Results indicate that when the mass loss of steel strands in Group A ranges from 0 % to 10.47 %, the cracking load decreases by 5.8821.57 %, and the ultimate bearing capacity decreases by 5.45–30.45 %. While for Group B, when the mass loss of steel strands ranges from 0 % to 14.26 %, the cracking load decreases by 3.75–25.00 %, and the ultimate bearing capacity decreases by 7.41–44.91 %. It is observed that as the degree of corrosion increases, both cracking load and ultimate bearing capacity of the beam gradually deteriorate, with the flexural capacity of partially grouted beams deteriorating faster. Built on this and with the model of bond reduction coefficient, an analytical method is proposed to predict the flexural capacity of CPTC beams under different grouting conditions. The developed method provides good predictions compared with experimental results of current study and from literature, paving the way for accurate assessment of the flexural bearing capacity of PTC beams with different grouting qualities in corrosive environments.

Corrosion of rebar often leads to the degradation of the bond-slip performance of reinforced concrete members, which is a serious issue in historical buildings. The bond-slip behavior of square rebar, which is widely used in historical reinforced concrete buildings, is significantly different from that of round rebar. In this paper, a bond-slip model of corroded square rebar reinforced concrete was developed. First, 18 square rebar reinforced concrete cube pull-out specimens are made, and the corrosion of rebars is accelerated by electrochemical corrosion experiments. Second, a universal global optimization method was used to construct the bond slip expression and the four-fold line bond-slip model with different corrosion rates was obtained by using the minimum Euclidean distance point. Third, the calculation formulas for the bond strength reduction coefficient and slip ratio of corroded square rebar-concrete in historical reinforced concrete buildings are derived. Finally, the bond-slip constitutive model of corroded square rebar-concrete in historical reinforced concrete buildings is established. The results show that the model is more accurate, simple, effective, and easy to use in practical engineering. The research results provide an important theoretical basis for the structural evaluation and conservation of historical reinforced concrete buildings.

Historical reinforced concrete (RC) buildings are culturally and aesthetically significant and require conservation due to aging. Strengthening RC buildings often requires the use of Fiber Reinforced Polymer (FRP) sheets, however distinct material properties of historical RC buildings have not been systematically considered yet. This study investigates the flexural behavior of historical RC beams strengthened by hybrid FRP sheets. A total of 11 beam specimens with varying FRP sheet configurations were tested using a four-point bending test to assess their flexural behavior, including failure mode, cracking pattern, load-deflection behavior, strain distribution, and ductility. The results showed that hybrid FRP sheets increased the maximum bearing capacity of strengthened specimens up to 30.2 %. An optimal fiber sheet configuration (T-3) is identified. 45-degree incline installation contributes to a 4.5 % increase in the bearing capacity of specimens. The average ductility loss of hybrid FRP sheets strengthened specimen (except for double-layer strengthened specimen) is 42 %, while an increase of sheet layer post adverse effect on ductility. Strain distribution conforms to the plane-section assumption. Additionally, a maximum bearing capacity calculation model was proposed, aiding the understanding of FRP strengthening in historical RC buildings.

Strong seedlings are essential for high yield. To explore the foundation of strong seedlings, we investigated various factors influencing the conversion and distribution of seed storage reserves during seedling establishment in maize inbred lines. Three maize inbred lines were used to explore the effects of seed size, seed vigor, illumination duration, temperature, water content, and salt concentration of the seedling medium on the utilization of seed storage reserves during seedling establishment. The results showed that the conversion rate of small seeds was 3.69 to 17.71% higher than that of large seeds. Moreover, prolonged illumination time was conducive to the formation of strong seedlings. However, low temperature, drought stress and salt stress reduced the conversion rate of seed storage reserves and increased the root/shoot ratio. These results could be used to guide field management during seedling emergence and develop improved germplasm with a high conversion rate of seed storage reserves.

In general, a plant model or its equivalent information, such as interactor matrix or the first several leading Markov matrices, is indispensable to the minimum variance (MV) performance assessment of a multivariate process. In this paper, a model-independent approach for performance assessment is developed to eliminate the requirement of a plant model. Without relying on any prior plant knowledge, the practical solutions are presented, in which the MV benchmark is obtained directly or is estimated in terms of the upper and lower bounds for the following different levels of available knowledge of the multivariate plant: (1) no knowledge available; (2) a known range of each entry in the pseudo first-Markov-matrix; (3) the available knowledge of the steady gain matrix for a first-order plus dead time (FOPDT) plant. The effectiveness of the proposed algorithm is verified through a classic numerical example and a practical example, namely, a “Shell” oil fractionator.

The maintenance prioritisation of infrastructure assets is conventionally evaluated by calculating the risk an asset can pose to the owner organisation in terms of agreed criteria. Multi-criteria decision-making (MCDM) methods are utilised to prioritise asset maintenance. Using fuzzy theory, which is developed to deal with vagueness in human thinking, is believed to release more accurate criteria weights and consequently alternative performance values in a qualitative multi-criteria decision-making evaluation. This paper presents an empirical application and comparison of four compensatory MCDM methods including technique for order of preference by similarity to ideal solution (TOPSIS), complex proportional assessment (COPRAS), weighted sum model (WSM), and weighted product model (WPM) in a fuzzy environment to prioritise irrigation asset maintenance. Analytical hierarchy process (AHP) method is used, also in a fuzzy environment, to obtain the criteria weights. Seven evaluation criteria and six irrigation channels from different areas in Northern Victoria, Australia, are considered as the case study data. Results of the MCDM methods are analysed and their reliability, simplicity, and applicability with pros and cons are evaluated. Finally, the most straightforward and at the same time reliable method for similar practical applications is suggested.

ABSTRACTThe current study evaluated the construct validity, internal consistency reliability, discriminant, and concurrent validities, along with the measurement invariance of the Brief Self-Control Scale (BSCS) among 1,216 Chinese participants, including 241 adult athletes, 412 adolescent athletes, 253 adult students, and 310 adolescent students. Confirmatory factor analyses (CFAs) supported the construct validity of the 8-item two-dimensional BSCS model, combining restraint and non-impulsivity. Cronbach’s alpha and composite reliability coefficients supported the internal-consistency reliability of the 8-item two-dimensional BSCS. Multi-group CFAs demonstrated the 8-item two-dimensional BSCS to be invariant at both configural and metric levels for all samples. Moreover, the restraint and non-impulsivity subscales exhibited discriminant validity and were also distinct from the conceptually related conscientiousness construct. Finally, it was revealed that the restraint component was positively associated with optimal sports performance of both adult and adolescent athletes, while non-impulsivity was only positively correlated to that of adolescent athletes. Both BSCS components had a positive association with academic performance of adolescent students. In conclusion, the 8-item two-dimensional BSCS is verified to be a reliable and valid measurement of trait self-control in Chinese athletes and students.

This paper presents the results produced from long-term tests designed to investigate the key factors affecting the external corrosion of cast iron pipes buried in clayey soil. The coupled effect of varying acidity (pH) and saturation (moisture content) of soil on the corrosion of cast iron buried in soil, including pitting corrosion, is thoroughly examined. Based on the observations and analysis of the test results, it is found that the coupled effect of high acidity (2.5 pH) and high saturation (80 %) of soil could create an accelerating environment for corrosion in the short term. In addition, the coupled effect of low acidity (5 pH) and high saturation (80 %) of soil could lead to a high corrosion rate for cast iron buried in the soil in the longer term. An empirical model for predicting pitting corrosion was also developed. The findings of this paper can have widespread applications, including corrosion protection and the development of models for the prediction of the remaining safe life of pipelines buried in corrosive soils.

The existing high-density distributed distribution network single-phase earth fault interval location method has the disadvantage of long positioning time. Hence, a single-phase earth fault interval positioning method for high-density distributed distribution network is proposed to solve this problem. In order to accurately locate the single-phase earth fault interval of distribution network, zero-order equivalent model of distribution network is built at first. Next the clustering algorithm is used to extract the single-phase earth fault characteristics, while the single-phase earth fault phase current increment is calculated by using the analysis method to obtain the single-phase earth fault phase current increment law. Then a fault-maximum interval T-shaped structure is built to divide the potential fault interval. Finally, the S-transformation is applied to accurately locate the single-phase earth fault interval, and the localization of the single-phase earth fault interval of the high-density distributed distribution network is achieved. The experimental results show that comparing with the existing high-density distributed distribution network single-phase earth fault interval positioning method, the proposed high-density distributed distribution network single-phase earth fault interval positioning method dramatically reduces the positioning time. It is fully explained that the proposed method in this article has a better positioning effect.

This study aimed to examine the relationships between occupational stressors, mental health problems, and sleep difficulty, and the mediating roles of cognitive fusion and cognitive reappraisal on the relationships in Chinese nurses. A total of 323 nurses (mean age = 32.11 ± 6.75 years) from 25 hospitals in China participated a cross-sectional online survey. Participants were asked to refer to the period during the severest time of the COVID-19 pandemic in China (January to March 2020) when assessing the psychological variables. The direct links from occupational stressors to cognitive fusion, cognitive reappraisal, mental health and sleep difficulty were significant. Cognitive fusion and cognitive reappraisal mediated the links from occupational stressors to mental health problems, while cognitive fusion and mental health problems mediated the links from occupational stressors to sleep difficulty. The sequential mediation via cognitive fusion and mental health problems as well as via cognitive reappraisal and mental health problems on the links from occupational stressors to sleep difficulty were also significant. Findings from the current study indicate that intervention strategies focusing on the reduction of cognitive fusion and improvement of cognitive reappraisal could help better prepare nurses to alleviate mental health problems and sleep difficulties that are related to COVID-19 and potentially similar pandemics in the future.

ABSTRACTAn accurate structural assessment of rails under combined effect of fatigue and corrosion prevents a phenomenal disaster, also saves millions of dollars and people’s lives. Recent studies which are proposed to simulate a precise model fail to take into account the different underlying mechanism for rail corrosion. The current study presents a numerical procedure to investigate crack initiation under combined effect of fatigue and corrosion. A three-dimensional (3D) finite element model (FEM) which accounts for rolling contact stresses due to wheel-rail contact loads is developed. Then, stress distribution is used in a MATLAB code to estimate the fatigue crack initiation life. The advantage of the proposed model is considering the combined effect of rolling contact fatigue and corrosion on structural integrity of rails. This model is applied to a case study of rail assessment in Melbourne, Australia. The cracks orientations and locations which were based on the FEM results were in good agreement with the field observations.

This paper presents a theoretical framework for developing a risk–cost optimised maintenance strategy for structures during their whole service life. A time-dependent reliability method is employed to determine the probability of structural failure and a generic form of stochastic model is developed for structural responses. To facilitate practical application of the proposed framework, a general algorithm is developed and programmed in a user-friendly manner. The merit of the proposed framework is that, in predicting when, where and whatmaintenance is required for the structure, all structural components and multi-failure modes are considered. It is found in the paper that, to ensure the safe and serviceable operation of the structure as a whole, some components need maintenance multiple times for different failure modes, whilst other components need “do nothing”. It is also found that ignorance of correlation amongst structural components and failure modes would underestimate the risk of structural failures in longer term and that the components with higher cost of structural failures require more maintenance actions. The paper concludes that the proposed framework can equip structural engineers, operators and asset managers with a tool for developing a risk–cost optimal maintenance strategy for structures under their management.

Practical experience and observation suggest that corrosion-affected reinforced concrete structures are highly susceptible to cracking. This paper presents an analytical time to corrosion-induced concrete cracking model based on fracture mechanics. The concrete cover load-bearing capacity is proposed and is used as a fracture criterion for concrete cracking. An accelerated corrosion test has been undertaken to produce data on time to corrosion-induced concrete cracking and crack width over time. A comparison between the analytical model and experimental results on time to concrete cracking and on crack width over time shows reasonable agreement. It is found that the distribution and size of the porous zone are non-uniform which is one of the main causes for discrepancy between results. The larger the porous zone is the longer it takes for concrete cover to crack due to corrosion. Although the experimental and model results exhibit similar trend, it is also found that assuming only a single propagating crack in analytical model results in an overestimation of corrosion-induced crack width. The models presented in this paper can serve as useful tool for serviceability and durability assessment of corrosion-affected reinforced concrete structures.

AbstractOver the last decade, mindfulness and acceptance-based approaches to mental training have been widely applied in the field of sport psychology. In order to develop a context-sensitive mindfulness and acceptance-based training program for Chinese athletes, the Mindfulness-Acceptance-Insight-Commitment (MAIC) program was developed. The MAIC is based on the Mindfulness-Acceptance-Commitment approach (MAC) and includes integrated elements of indigenous Chinese culture such as the acceptance-based adversity coping, social-oriented values, and insight. The current article will briefly revisit and discuss the theoretical considerations, the main components, the applications and reflect on the MAIC program.

This work developed a bioaugmentation strategy that simultaneously reduced soil di(2-ethylhexyl) phthalate (DEHP) pollution and its bioaccumulation in Brassica parachinensisby inoculating the isolated strain Rhodococcussp. 2G. This strain could efficiently degrade DEHP at a wide concentration range from 50 to 1600 mg/L and transformed DEHP through a unique biochemical degradation pathway that distinguished it from other Rhodococcusspecies. Besides, strain 2G colonized well in the rhizosphere soil of the inoculated vegetable without competition with indigenous microbes, resulting in increased removal of DEHP from soil (∼95%) and reduced DEHP bioaccumulation in vegetables (∼75% in the edible part) synchronously. Improved enzyme activities and DOC content in the rhizosphere of the planting vegetable and inoculating strain 2G were responsible for the high efficiency in mitigating DEHP contamination to vegetable cultivation. This work demonstrated a great potential application to grow vegetables in contaminated soil for safe food production.

Ground cherry (Physalis pubescens) is widely cultivated in Northeast China as one of its popular fruits. In the summer of 2017, suspected bacterial disease symptoms consisting of water-soaked spots and brown interveinal necrotic lesions with chlorotic margins were observed on ground cherry leaves in a field of Hailun County in Northeast China. From infected leaves, bacteria with pale-yellow, mucoid, domed circular colonies were repeatedly isolated. Based on biochemical tests and genetic characterizations of hrpBand concatenated four housekeeping genes (lepA-gyrB-gapA-gltA), the bacteria isolates obtained in this study were identified as Xanthomonas euvesicatoriapv. euvesicatoria. Pathogenicity of these isolates was confirmed on ground cherry, tomato and pepper seedlings by artificial inoculation. It was further confirmed that none of the related pathogens X. vesicatoria, X. gardnerior X. euvesicatoriapv. perforanswere detected by species-specific PCR in field samples. To our knowledge, this is the first report of X. euvesicatoriapv. euvesicatoriacausing bacterial spot of ground cherry in China.

The torque impactor can effectively solve the stick-slip vibration of PDC bit in the deep formation, but the wear of the pendulum seriously restricted the service life of the impactor. In order to reduce the wear of the pendulum under complicated working conditions, the polycrystalline diamond composite material was used as the wear-resistant material to design the pendulum wear-resistant belt. Based on the analysis of the feasibility of using polycrystalline diamond as pendulum wear-resistant material, the finite element model of dynamic contact interaction between pendulum wear-resistant belt and impact cylinder was established, the influence of the arrangement of wear-resistant blocks on the stress of the contact area between the pendulum wear-resistant belt and the impact cylinder was studied. The results show: Polycrystalline diamond composite material has stronger wear resistance and better anti-friction performance than conventional wear-resistant materials, and can reduce the wear of the inner wall of the impact cylinder, which is feasible on the surface of the pendulum hammer. The use of the wear-resistant belt structure is beneficial to improve the variation of the shear stress of the area where the pendulum and the impact cylinder contact each other. The wear-resistant belt structure is beneficial to improve the shear stress variation amplitude of the pendulum and impact cylinder in contact with each other. When the wear-resistant block is arranged in a circular block staggered arrangement, the shear stress change amplitude of the interaction contact area is the largest, the triangular block staggered arrangement mode is second, and the trough block shape staggered arrangement is the smallest. The research results have important reference significance for the design and application of polycrystalline diamond composite pendulum wear-resistant belt.