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Reinforcement corrosion induced by chloride penetration is a major threat to reinforced concrete structures in marine environments. The use of surface treatments to improve the durability of reinfo...

The use of supplementary cementitious materials (SCMs) around the world to improve concrete performance has increased in recent decades. However, the application of SCMs remains limited by their heterogeneity and variability. Engineering practices demand a unified model for SCMs to predict and optimise the performance of blended concrete. A multiphase modelling scheme that covers various SCMs is therefore proposed in this study. Following this modelling scheme, three low-calcium fly ashes were selected and comprehensively studied by scanning electron microscopy–energy dispersive X-ray spectroscopy (SEM-EDS) full-element mapping and image analysis. The pozzolanic reactivity of these three fly ashes was further investigated in alkaline and cement systems. A temperature-dependent two-phase pozzolanic reaction model (silicate and Al-silicate glass) considering fly ash material variations was proposed to predict the pozzolanic reaction and therefore the degree of reaction at different temperatures. The numerical results show that the proposed multiphase modelling scheme has great potential to cover various SCMs.

Natural resources depletion is gradually becoming a critical burden on the environmental and ecological balance, pushing the development of artificial aggregates forward. In order to curb the shortage issues of natural aggregates and minimize the destruction of land topography, alkali-activated aggregates (AAA) have gradually become a hot topic in recent years as a new application of alkali-activated materials (AAM) with the benefits of utilizing industrial by-products and waste materials. This article provides an overall review of the manufacturing process and engineering properties of two types of artificial aggregates, cold-bonded AAA (CB-AAA) and sintered AAA (ST-AAA). Their applications in concrete, besides the mechanical evaluation, durability performance, and leaching behavior, are summarized based on the existing research outcomes. Finally, the future perspectives and challenges of artificial aggregates development are also proposed.

The use of supplementary cementitious materials (SCMs) to improve concrete performance has increased around the world in recent decades. Engineering practices demand a unified model for SCMs to predict and optimise the performance of blended concrete.DuCOM-COM3 is a multi-chemo-physical and multiscale analysis platform that can trace the whole-life behaviour and performance of reinforced concrete structures. However, the intrinsic heterogeneity and variability of SCMs present great challenges to the modelling of blended concrete. This paper first reviews the challenges and difficulties of current models of blended concrete. A multiphase modelling scheme based on DuCOM-COM3 analysis platform is introduced to consider different SCMs. Using the modelling scheme, a research road map for blended concrete modelling is introduced for future study. It is hoped that the roadmap will help to reveal the mechanism of SCM reactions and their effect on concrete performance.

Le Wang, Tiao Wang, Jia-Qi Gu, Hui-Bin Su Department of Anesthesiology, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou, 215000, China Purpose: Sevoflurane is widely used in lung cancer surgery. It is well known that volatile anesthetics have a lung-protective effect in lung cancer surgery. However, the association between the inhibition of cancer cells and miRNAs interference remains unknown. Whether sevoflurane can affect some miRNAs in A549 cells has not been reported. The main aim of the present study was to investigate the effect of 3% sevoflurane on A549 cells and assess whether it regulates A549 cells by interfering with miRNA. Methods: In three percent sevoflurane-pretreated A549 cells, treated for a duration of 30 minutes, the apoptosis rate of A549 cells was evaluated using a flow cytometer. The expression of 6 types of miRNAs associated with non-small cell lung cancer was analyzed by real-time quantitative polymerase chain reaction. Results: An obvious apoptosis-promoting effect was found in A549 cells, which had been treated with 3% sevoflurane. The expression of several miRNAs that regulate apoptosis was significantly changed compared with the control group. Conclusion: Three percent sevoflurane can significantly increase the apoptosis rate of A549 cells, which may reduce the spread of cancer cells caused by operation. Sevoflurane disturbed the expression of the miRNAs that regulate apoptosis. Keywords: sevoflurane, miRNAs, apoptosis

Supplementary cementitious materials (SCMs) significantly improve concrete performance. However, the application of SCMs remains limited by their heterogeneity and variability. This study investigated the pozzolanic reaction and curing temperature-dependence of low-calcium fly ash in cement systems over 2 years. The experimental results show that fly ashes have different reactivities and temperature dependencies even though they have similar material properties. A modified tangential method was developed for thermogravimetric analysis of the calcium hydroxide content and chemically bound water of fly ash-blended cement paste. The chemical composition of an aluminium-modified calcium silicate hydrate (C-(A)-S-H) gel of fly ash-blended cement paste was studied by scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM-EDS) with image analysis. The experimental results show that as the Ca/Si ratio decreased in fly ash–cement paste, the Al/Si ratio increased. The Al/Si distribution of fly ash-blended cement paste varies widely from 0.05 to 0.50 with no specific maximum. The typical Ca/Si and Al/Si ratios of C-(A)-S-H gel in fly ash cement paste are approximately 1.40 and 0.25.

The use of fly ash to improve concrete performance has increased around the world in recent decades. However, the engineering application of fly ash remains limited by its heterogeneity and variability. This paper presents a developed approach for comprehensive characterisation of fly ash material properties based on scanning electron microscopy–energy-dispersive X-ray spectroscopy full-element mapping with image analysis. The chemical compositions, mineralogical and amorphous phase assemblage and specific surface area of each phase can be visually analysed and quantified. Analysis reveals that the phase assemblage of fly ash is affected by its combustion conditions. Although a wide distribution of crystalline mullite can be found in fly ash particles, crystalline quartz is usually covered by amorphous silicate. The characterisation approach developed in this study is used to investigate the influence of crystal components on kinetic properties of various phases of fly ash in alkaline conditions. The results show that crystalline mullite affects the kinetic properties of Al-silicate glass and glass-mullite intermixtures.

Background Paddy soil dissolved organic matter (DOM) represents a major hotspot for soil biogeochemistry, yet we know little about its chemodiversity let alone the microbial community that shapes it. Here, we leveraged ultrahigh-resolution mass spectrometry, amplicon, and metagenomic sequencing to characterize the molecular distribution of DOM and the taxonomic and functional microbial diversity in paddy soils across China. We hypothesized that variances in microbial community significantly associate with changes in soil DOM molecular composition. Results We report that both microbial and DOM profiles revealed geographic patterns that were associated with variation in mean monthly precipitation, mean annual temperature, and pH. DOM molecular diversity was significantly correlated with microbial taxonomic diversity. An increase in DOM molecules categorized as peptides, carbohydrates, and unsaturated aliphatics, and a decrease in those belonging to polyphenolics and polycyclic aromatics, significantly correlated with proportional changes in some of the microbial taxa, such as Syntrophobacterales, Thermoleophilia, Geobacter, Spirochaeta, Gaiella, and Defluviicoccus. DOM composition was also associated with the relative abundances of the microbial metabolic pathways, such as anaerobic carbon fixation, glycolysis, lignolysis, fermentation, and methanogenesis. Conclusions Our study demonstrates the continental-scale distribution of DOM is significantly correlated with the taxonomic profile and metabolic potential of the rice paddy microbiome. Abiotic factors that have a distinct effect on community structure can also influence the chemodiversity of DOM and vice versa. Deciphering these associations and the underlying mechanisms can precipitate understanding of the complex ecology of paddy soils, as well as help assess the effects of human activities on biogeochemistry and greenhouse gas emissions in paddy soils.

The deflection of reinforced concrete (RC) beams with low span-effective depth ratios can be attributed equally to shear and flexural deformations. Although truss models can be used to evaluate shear deformation, their prediction accuracy is strongly dependent on how the diagonal crack angle is estimated. This paper presents the results from an experimental test of nine RC beams that failed in shear and had low span-effective depth ratios (i.e., a / h 0 3 ). It then proposes a multi-angle truss model for predicting ultimate shear deformation while considering the effect of the bending moment variation along the span on diagonal crack angles. An empirical formula is also presented to predict the shear stiffness degradation of RC beams up to the ultimate state through regression analyses. Numerical results show that the proposed multi-angle truss model can be used to predict the shear deformation of RC beams with low span-effective depth ratios with reasonable accuracy.

Supplementary methods. (DOCX 32 kb)

Supplementary results about consistence between metagenomic data and 16S rRNA data. (DOCX 29 kb)

The brainstem is well recognized as a critical site for integrating descending modulatory systems that both inhibit and facilitate pain at the level of the spinal cord. The cerebrospinal fluid-contacting nucleus (CSF-contacting nucleus) distributes and localizes in the ventral periaqueductal central gray of the brainstem. Although emerging lines of evidence suggest that the CSF-contacting nucleus may be closely linked to transduction and regulation of pain signals, the definitive role of the CSF-contacting nucleus in pain modulation remains poorly understood. In the present study, we determined the role of the CSF-contacting nucleus in rat nocifensive behaviors after persistent pain by targeted ablation of the CSF-contacting nucleus in the brainstem using the cholera toxin subunit B-saporin (CB-SAP), a cytotoxin coupled to cholera toxin subunit B. Compared with CB/SAP, CB-SAP induced complete ablation of the CSF-contacting nucleus, and the CB-SAP-treated rats showed hypersensitivity in responses to acute nociceptive stimulation, and exacerbated spontaneous nocifensive responses induced by formalin, thermal hyperalgesia and mechanical allodynia induced by plantar incision. Furthermore, immunohistochemical experiments showed that the CSF-contacting nucleus was a cluster of 5-HT-containing neurons in the brainstem, and the spinal projection of serotonergic axons originating from the CSF-contacting nucleus constituted the descending 5-HT pathway to the spinal cord. CB-SAP induced significant downregulation of 5-HT in the spinal dorsal horn, and intrathecal injection of 5-HT significantly reversed hypersensitivity in responses to acute nociceptive stimulation in the CB-SAP-treated rats. These results indicate that the CSF-contacting nucleus 5-HT pathway is an important component of the endogenous descending inhibitory system in the control of spinal nociceptive transmission.

General education (GE) is a new fashion in Chinese university courses, as can be seen by the fact that a GE curriculum has been set in several high-ranking universities in China recently. These courses include knowledge of history, arts, science, society, law and medicine, etc., and require English as the bridge between Chinese cultures and English cultures. English departments (or schools) are responsible for introducing foreign civilization within the framework of GE, resulting in the increasingly crucial role of English teachers in China in helping students to develop their intercultural knowledge, skills and awareness. In this new curriculum, teachers and students must acquire the skills for English reading, news listening, academic writing, and conference presenting. This changing scenario means that intercultural competence will need to be a new goal for all English teachers and students in China. In this paper, the development of GE in China is discussed, along with the setting of core courses for ...

In order to improve the cleaning effect and efficiency of the aluminum package used for carrying electronic aluminum liquid a new cleaning machine of aluminum package was put forward. Three standard cutters is used in new equipment to mill the inner cylindrical surface and end surface by moving in an epicyclic way. The cutting efficiency could be enhanced due to the appropriate capability carried by the cutters. The radial adjusting device of the cutter disk make the processing range flexible, thus increase the applicability of the equipment. Based on the analysis and research on the cutting devices of the new-structure aluminum package cleaning machine and the simulated to the machine processing it is demonstrated that the strength and stiffness of the cutting devices are qualified, and the design of the cleaning machine tool is practical.

For a long time, the instruction of navy equip.’s detections and maintenance is the traditional theories, and the plan servicing is the main instruction thought and organized form. But with the development of electrification and digitization, the traditional method may cause disrepair and excessive repair. It is hard to satisfy the maintenance support requirement of equipment, and restrict the formation and advance of fighting strength. The paper researches the characteristic of CBM and the choice of object and the choice of state information parameter and the choice of monitor means and etc., and provides a set of method and thinking to develop the maintenance of condition based maintenance for equipment. Introduction The theories of condition based maintenance and proactive maintenance get development in civil realm. But it is not enough in military realm. The main reason is how to build a bridge between the theories and equip manage, and it provides the equip manager with the method that how to develop scientific management. The paper researches the characteristic of CBM and the choice of object and the choice of state information parameter and the choice of monitor means and etc., and provides a set of method and thinking to develop the maintenance of condition based maintenance for equipment. In order to realize the CBM, the first is to estimate the state of equip, and then makes the repairing method based on the state. In other words, it includes state detections and fault diagnosis and maintenance decision. The state detection is using the instrument to show the parameter, and fault diagnosis and estimation is analyzing the reason and place and degree based on the various parameters from state decision-making system. It analyzes and judges the operating conditions by state data, and provides data support for repair decision [1-2]. State Detection State detection is the first step to carry out the maintenance decision based on the status, and is the precondition and base to forecast the residual life and optimize the maintenance decision. It can detect cerntain state parameter of object by monitoring, and valuate the operating conditions primarily. In the actual engineering application, two types of problems should be solved, and one is characteristic parameter that needs to be detected, and the other is the suitable detecting technique. Confirm the state detecting characteristic parameter During the operating, it can produce all kinds of physical phenomenon that represents the state, such as vibration and noise and temperature and etc... And it can cause the change of corresponding parameter. All these provide the possibillity for the state detection. In actual application, we should choose the parameters that reflect the operating state most to detect. Choose the state detecting technique After confirming the characteristic parameter of detecting equip, we shuold choose the suitable detecting technique to achieve the state deteccting information. Currently, there are many kinds of detecting technique that can be used in actual engineering, such as kinetic effect and chemical effect 6th International Conference on Electronic, Mechanical, Information and Management (EMIM 2016) © 2016. The authors Published by Atlantis Press 1 and physical effect and so on. Among them, kinetic effect and chemical effect are the most extensive technique currently. Process the State Information When detecting the state, it is necessary to use sensor and measure instrument to change the characteristic parameter into discrete or continuous electrical signal. These original electrical signals contain the important information of equip or assembly state. Two problems shuold be solved if these electrical signals can be used in CBD. One is how to eliminate the noise interference of original signals with maximum limit, and then give prominence to the useful information. The other is how to process and analyze the signal, and then find the inside regulation. An effective path to solve the problem is the processing of state information, and it is an important part in CBM decision. In the actual application, the process of signal treatment is as follows: The pretreatment of signal The signal acquiring by state detecting includes noise and information. The purpose of signal pretreatment is eliminating the influence of noise in the maximun limit and improving the signal-to-noise ratio and standing out the useful information. Confirming the signal character The signals acquiring from state detecting have many types and have its character respectively. It needs to describe them with different parameter and needs to use different methods to acquire the parameter. The familiar testing of signal character has periodic and random testing and ergodicity testing and stationarity testing. The processing and analysis of signal The work that process and analyze the signal is acrried on crosswise. Residual Life Prediction The residual life prediction is the key of making the CBM decision. In is necessary to predicte the residual life in order to realize the scientific and quantificational follow-up decision. The definition of residual life is using certain predicting method to estimate the residual life based on the historical and current state. In this paper, the residual life does not limit in the specialized sense. Choose the life characteristic parameter Choosing the life characteristic parameter is the first step to carry on residual life prediction, and is the precondition and base of the following link. Usually, the parameter that can stand for the life characteristic has residual life and reliability and risk rate etc. Establish or choose the model After confirming the life characteristic parameter, how to describe the relationship between state information and life characteristic parameter becomes the key of the whole process. An effective path to solve the problem is establishing or choosing the mathematic model. We choose operating time and state information as variate, and describe the relationship accurately by mathematic expression. Generally speaking, it needs eatablish or choose different method because of different characteristic parameter. Now, the residual life prediction models that can be choosed and mature have filtering model and proportional model. They chooses residual life distribution density function and risk ratio as life characteristic parameter respectively, and estabish the model, and realize the the quantificational description between state information and life characteristic. Parameter estimation and testing It is ineluctable to induct some parameters during the process of choosing or establishing the model. These parameters reflect the whole life characteristic of equip from certain degree, and it is important for the whole residual life prediction. Therefore, we need to eatimate the parameters in model based on the state information data and life inforamtion data. In the actaul engineering application, we

Due to the random spatial distribution and fast motion of rain, removal of rain in video is a more difficult problem. This paper presents a background subtraction based on sample model to remove the rain. First, analyze the properties of rain, then establish the sample model with values randomly take in the spatial neighborhood of each pixel on the first frame, so better to classify detected rain by background subtraction. In addition, the movement of objects will cause the corresponding color pixel brightness values to change significantly, the H component of the HSI color space was applied to reduce the impact of moving objects on rain removal. Experimental results show that this method compared with existing methods can not only eliminate a good rain, but also have faster processing speed.

The aim of this study was to investigate tumor recurrence characteristics of hepatocellular carcinoma (HCC) after liver transplantation (LT), including recurrence sites, time and risk factors, and to provide a basis for predicting and preventing tumor recurrence.Data from 224 consecutive patients with HCC who underwent LT between Feb 1999 and December 2008 at our center had been retrospectively analyzed. Tumor-unrelated, perioperative and in hospital deaths were excluded (n = 39). All the cases were followed-up regularly. According to recurrence or not, the cases were divided into recurrence group (n = 103) and non-recurrence group (n = 99). The data were analyzed statistically.Extrahepatic and single site recurrences were more common in early postoperative days, especially in the lung. No significant relation was observed between recurrence sites and time. Exceeding Milan criteria (MC), macrovascular invasion, liver capsule invasion, satellite lesions and Tumor-Node-Metastasis (TNM) classification of UICC were observed significant different in univariate analysis. TNM classification and macrovascular invasion were considered 2 independent risk factors in multivariate analysis. Macrovascular invasion was a independent risk factor for very early recurrences (6 months).Recurrence of HCC after LT was not frequent at intrahepatic but extrahepatic sites. The recurrence time was mainly in early operative days. TNM classification and macrovascular invasion are risk factors. Macrovascular invasion is associated with early recurrence.