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Background Even mild renal disease is a powerful cardiovascular risk factor. However, the association between these pathophysiologic processes (especially in the early asymptomatic stage) is not known. Methods We recruited 243 asymptomatic patients with Stages 1–4 chronic kidney disease (CKD) without obstructive coronary artery disease (CAD). We distinguished different degrees of severity of intrarenal arterial lesions (IALs) according to the Oxford classification. Myocardial microcirculation perfusion was measured using single-photon emission computed tomography (SPECT). Summed scores of 17 stress and rest image segments produced the summed stress score (SSS) and summed rest score (SRS), respectively. The summed difference score (SDS) was calculated as the difference between the SSS and SRS. Coronary microvascular disease (CMD) was defined as abnormal SPECT (SSS ≥4 or SDS ≥2) in the absence of obstructive CAD. Results Participants showed a stepwise increase in CMD severity with IAL aggravation. SSS of no/mild/moderate/severe IALs was 1.64 ± 1.08, 2.56 ± 1.35, 4.42 ± 2.17 and 6.48 ± 3.52, respectively (P Conclusions We demonstrated, for the first time, that impaired perfusion in the myocardial microcirculation in asymptomatic patients with Stages 1–4 CKD with IALs. Renal arteriolar hyalinization may be a useful marker of CMD in CKD.

A large number of thermo-image measurements are useful in determining the water and energy status of ornamental tree or shrubs, especially when using certain improved parameters and methods. With these parameters and proper methods, data comparability in thermo-image analyses of ornamental tree/shrubs have been improved. In a large number of thermographic measurements, we found a significantly high-image temperature or ‘’fever” status in stressed tree or shrubs in sunny summer midday because of their transpiration cooling failure. Leaf withering, scorching, reddening, shedding and green losing can be the typical symptom patterns after persistent “fever” which is a dangerous signal unadapted to local environment and originate from persistent water and energy imbalance. The utilization of parameter of thermo-difference between leaf and finger of observer (TDlf) supports this idea.

A new alkaloid named zhebeisine (

The Aral Sea basin is the most active source of salt-dust storms in the central Asian region, while its exposed bottom is acting as a “distributer” of salts and chemicals over the adjoining areas. In this study, the Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT-4) is used to identify the trajectories of air parcels from the dried bottom of the Aral Sea region (45.40° N, 61.30° E) that are potentially containing salt-dust and their probability of influencing the downwind area in the period of 2016–2020. The frequency of air parcel trajectory was mapped for six levels: 100, 300, 500, 1000, 2000, and 3000 m agl. The trajectories were categorized by k-means clustering into four clusters that are named by their direction of movement as follows: Cluster 1: E category, Cluster 2: NE category, Cluster 3: W category, and the Cluster 4: S category. The 72 h of forward trajectories showed that salt-dust storms starting from the dried bottom of the Aral Sea had the highest probability of affecting the northeastern region e.g., Siberian Plain, followed by the southern region e.g., Iran Plateau. Total number of trajectories within these two clusters (NE and S) accounts for 90% (or 413 days) of trajectories in examined days. The main area of influence of salt-dust is close to the source area. The potential transport distance of salt-dust particles increases with the height of the starting point. The surface wind, which results from the changes of the Siberian High (SH), has a major role in shaping the surface atmospheric circulation which determines the transport pathway of salt-dust particles over the Aral Sea region. The results of this study could be useful to forecast the potential occurrence of salt-dust storms in downwind affected areas and would also be helpful to understand the possible causes of salt-dust storms which can provide the scientific basis for mitigation of the negative impact of salt-dust storms on the environment and human health. Further research should be conducted by using monitoring data to confirm the deposition of dust and salt particles in those areas mapped by our study.

The stability of reservoir bank slopes is always of great concern in hydropower construction. After impounding, some unstable slopes may fail, leading to landslides with significant displacements. This work investigated the vertical and horizontal displacements of the Yizicun landslide before and after impoundment of the Xiluodu Reservoir on the Jinshajiang River, southwestern China using InSAR technique and data from ALOS PALSAR, ENVISAT–ASAR, TerraSAR-X and Sentinel-1. The purpose was to explore the relationships between the ground surface deformation and the landslide movement mode, and to make further analysis on its deformation characteristics. Combining with field investigations, the analysis of InSAR reveals that the Yizicun landslide was a push type before impoundment and is a pull type after impoundment. This landslide is largely a whole slump with multiple slip surfaces. After the impoundment of the reservoir, the landslide boundary had a tendency to spread, and its rear edge has extended backward about 20 m. More fissures and secondary landslides appeared on the southern boundary than those in the north. The horizontal movement changed from southwestward to westward, and the vertical deformation increased. The current stability of the landslide might be subjected to a combined action of ground water levels and precipitation intensity. The study also indicates that InSAR has many inimitable advantages in the study of reservoir landslides, such as backtracking for stability of bank slopes before impounding, three-dimensional monitoring of active areas, landslide movement mode analysis and so on. Thus, it is a suitable method to efficiently analyze landslide deformation characteristics before and after reservoir impoundment, which is of great significant for detecting and monitoring reservoir landslides.

Despite its ubiquitous presence in the built environment, the dynamic tensile fracture behaviour of concrete under a high strain rate is still not completely understood. In this study, a three-dimensional meso-scale finite element model is developed to investigate the dynamic tensile fracture behaviour of concrete. On the meso-scale, concrete is regarded as a composite of aggregate, mortar and the interface transition zone (ITZ). The nucleation, coalescence, and propagation of cracks are modelled by pre-insert rate-dependent cohesive elements. Predicted results of the proposed numerical model fit well with experimental data in spall tests. The evolution of cracks in concrete under dynamic loading is explicitly presented. The micro-cracks of concrete are widely distributed before the initiation of macro-cracks. The results suggest that the inertia effect plays an important role in the dynamic fracture behaviour of concrete. Moreover, the influence of the mesostructure on the dynamic tensile strength is investigated. The dissipated fracture energy under dynamic loading is also indicated to be affected by the mesostructure of concrete.

Concrete has a high degree of heterogeneity and a complex porous structure, so to accurately study the performance evolution mechanism of concrete, multi-scale research should be carried out. A three-phase meso-model of concrete is constructed based on the method of randomly generating particles. A meso-macro connection framework is built, and the accuracy of the fixed hygro-thermo-chemical model at the meso-scale is verified through comparing its outcomes with experimental data and macroscopic results. The hygro-thermo-chemical behaviours of early-age concrete at the meso-scale are studied under adiabatic–sealed, radiating–sealed and adiabatic–drying conditions, by considering the cooling effect of the aggregate, low diffusivity of the aggregate, high diffusivity of the interface transition layer and concrete gradation. Additionally, distribution and evolution of several eigenvalues, such as the relative humidity, are obtained.

HK853 is a transmembrane protein from Thermotoga maritime, which belongs to HK853/RR468 two-component signal transduction system (TCS) and acts as a sensor histidine kinase. HK853 is mainly composed of a transmembrane domain, dimerization and histidine-containing phosphotransfer domain (HK853DHp), catalytic and ATP-binding domain (HK853CA) and several linkers. HK853 can be completely autophosphorylated, which is the first step for signal transduction of TCS. HK853CA is an essential domain for its kinase function, since HK853CA could bind with ATP and convert it to ADP. Here, we report the backbone and part of side chain assignments of HK853CA. By analyzing the chemical shifts of HN, N, CO, Cα and Cβ, the secondary structure was predicted and contrasted with the published crystal structure of HK853CA. The result showed that our predicted structure could basically fit into the crystal structure. Thus, the chemical shift assignments of HK853CA are the starting point for further structural and dynamics study.

Background: Myofibroblast (MF) activation is the key event of irreversible renal interstitial fibrosis. Anoikis resistance is the hallmark of active MFs, which is conferred by continuous activation of the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/protein kinase B (Akt) pathway. Our previous study found that tumor-suppressing STF cDNA 3 (TSSC3) enhances the sensitivity of cells to anoikis via the PI3K/Akt pathway. Therefore, we hypothesized that TSSC3 might suppress renal interstitial fibrosis by inducing anoikis via the PI3K/Akt pathway. Methods: Cell anoikis was induced by the exogenous addition of RGD-containing peptides or by culturing cells in suspension. MFs were established by stimulating HK-2 renal tubular epithelial cells with transforming growth factor beta 1 (TGF-β1). Lentivirus vectors were to construct a TSSC3 overexpression cell model. The effects of TSSC3 on the anoikis, growth, migration, invasion, and contraction of MFs were determined using annexin V-fluorescein isothiocyanate assays, cell counting kit-8 assays, wound healing migration assays, matrigel invasion assays, and collagen-based contraction assays. Results: The results demonstrated that TGF-β1, simultaneous with the induction of MF differentiation, confers significant protection against anoikis-induced cell death, which could be partly reversed by treatment with the PI3K/Akt pathway inhibitor, LY294002. Moreover, overexpression of TSSC3 obviously impaired cell growth, cell migration, cell invasion, contraction, and anoikis resistance of MFs, and decreased the activity of the PI3K/Akt pathway and the production of extracellular matrix molecules, all of which could be attenuated by treatment with the PI3K/Akt pathway activator, 740Y-P. Taken together, this study suggested that TSSC3 attenuates the anoikis resistance and profibrogenic ability of TGF-β1-induced MF by regulating the PI3K-Akt pathway. Conclusion: These findings provide a biological basis for further exploration of the therapeutic significance of targeting MF via TSSC3 in renal interstitial fibrosis.

Underground mining in coal mining areas will induce large-scale, large-gradient surface deformation, threatening the safety of people’s lives and property in nearby areas. Due to mining-related subsidence is characterized by fast displacement and high nonlinearity, monitoring this process by using traditional and single interferometric synthetic aperture radar (InSAR) technology is very challenging, and it cannot accurately and quantitatively calculate the deformation of the mining area. In this paper, we proposed a new method that combines both multitemporal consecutive D-InSAR and offset tracking technology to construct a complete deformation field of the coal mining area. Taking into account the accuracy of multitemporal consecutive D-InSAR in calculating small deformation areas and the ability of offset tracking to measure large deformation areas, we utilized their respective advantages to extract the surface influence range and applied an adaptive spatial filtering method to integrate their respective results for inversion of the deformation field. 12 ascending high-resolution TerraSAR-X images (2 m) from September 3, 2018, to October 26, 2019, and 39 descending Sentinel-1 TOPS SAR images from August 5, 2018, to November 4, 2019, in the Ordos Coalfield located at Inner Mongolia, China, were utilized to obtain the whole subsidence field of the working faces F6211 and F6207 during the 454-day mining period. The GPS monitoring station located in the direction of the mining surface is used to verify the accuracy of the above method; at the same time, to a certain extent, the difference between the unmanned aerial vehicle’s DSM data acquired after coal mining and the Shuttle Radar Topography Mission (STRM) DEM can qualitatively verify the accuracy of the results. Our results show that the results of TerraSAR are basically consistent with the deformation trend of GPS data, and that of Sentinel-1 have large errors compared with GPS. The maximum central subsidence reaches ~12 m in the working face F6211 and ~4 m in the working face F6207. In the working face F6207, the good agreement between GPS and TerraSAR results indicated that the method above using high-resolution SAR data could be reliable for monitoring the large deformation area in the mining field.

A film is often marked with the brand of the times, about people and things of a certain era, reflecting the social problems of that era. This paper analyzes the characteristics of the protagonists in the two films and excavates the deep connotation of the film. From the four aspects of marginal people, protagonist's experience, character alienation, belief and choice, this paper analyzes the different behavior orientations and respective fates of the bottom people in the two films, who are also the marginal people who are struggling to survive in a certain era.

Concrete gains its strength from the precipitation of a calcium-alumino-silicate-hydrate (C-A-S-H) colloidal gel, which acts as its binding phase. However, despite concrete's ubiquity in the building environment, the atomic-scale mechanism of C-A-S-H precipitation is still unclear. Here, we use reactive molecular dynamics simulations to model the early-age precipitation of a C-A-S-H gel. We find that, upon gelation, silicate and aluminate precursors condensate and polymerize to form an aluminosilicate gel network. Notably, we demonstrate that the gelation reaction is driven by the existence of a mismatch of atomic-level internal stress between Si and Al polytopes, which are initially experiencing some local tension and compression, respectively. The polymerization of Si and Al polytopes enables the release of these competitive stresses.

PhoB is a response regulator of the PhoR/PhoB two-component signal transduction system that is involved in the regulation of the phosphate (Pho) regulon of Escherichia coli. PhoB has two domains, receiver domain and effector domain. The receiver domain can be phosphorylated by its cognate histidine kinase PhoR and the phosphorylation induces conformational changes of the full length protein of PhoB that promote the DNA binding and transcription. Three-dimensional crystal structures of PhoB receiver domain (PhoBN) have been solved under apo or BeF3− (a phosphoryl analog) binding forms and it has been found that PhoBN is dimerized in both situations. However, we have found that the apo form of PhoBN has multiple conformational changes in solution that is hard to be distinguished by using NMR spectroscopy, while the mutagenesis of F20D PhoBN gives homogeneous dispersed signals in HSQC spectrum indicating a relatively uniform conformation. Meanwhile the F20D mutant has the same phosphorylation activity as the wild type protein. Here we report the backbone assignment of PhoBNF20D mutant. The chemical shift (HN, N, CO, Cα and Cβ) analysis shows that the predicted regions of secondary structure are in good agreement with those observed in the crystal structure of apo PhoBN. Therefore, the backbone chemical shifts assignment of PhoBNF20D mutant would be useful for studying the structure and dynamics of PhoB receiver domain and it has significance for explaining the mechanism of phosphorylation in TCSs.

This work presents a comprehensive coupled thermal-hydro-mechanical model to simulate both freezing and thawing processes in concrete while considering liquid overpressure and the deterioration of material characteristics. The proposed model is validated through a comparison with available experimental data obtained from the literature. A random polygons meso-structure of concrete is established, within which the mortar, interfacial transition zones (ITZs) and aggregates are distinctly represented. Mesoscopic finite element simulations are conducted to assess the effects of the permeability of mortar and the ITZs, the thermal expansion property of the ITZs, aggregate volume fraction and aggregate gradation. The outcomes indicate that the permeability of the ITZs and the aggregate volume fraction play a significant role in the freezing/thawing behavior of concrete. Furthermore, the impacts of the thermal expansion property of ITZs and the aggregate gradation should not be overlooked.

Based on a fixed hygro-thermo-chemical model that is clearly distinguishable from other models in the existing literature, this work conducts a finite element analysis of heat transfer and moisture transport for concrete at an early age and beyond. Numerical validations show that this fixed model corresponds to the hydration heat liberation rate for ordinary Portland cement and reflects the two-phase process of the relative humidity changes. Simulations of concrete samples with various water-cement ratios are performed, and the outcomes are compared to experimental temperature and relative humidity curves, confirming that the modified model has relatively high accuracy. The simulated influential depths of moisture transfer in concrete are also in accordance with the results from theoretical equations.

Recent climate effects include severe fluctuation and an increasing probability of extreme meteorological events, such as seasonal and annual drought, the succession between typhoons and summer drought, between low temperature and winter drying, and even the association between high tide and high temperatures. We studied the wilting of Japanese black pine ( Pinus thunbergii Parl.) by investigating the age, site properties and injury status of wilted trees. The water and energy imbalances of wilted trees were determined by measuring the imaging temperature and anthocyanin content and by performing a meteorological analysis. We found a heavy rainfall after a successive normal climate induced the lush growth and secondary height growth of P. thunbergii , which is sensitive to winter drying injury. Pines wilted because of the internal water and energy imbalance due to a sudden change of precipitation and cold injury, especially pine trees growing at unfavorable site conditions. In Northeast Asia and along the coast of China, such extreme changes of precipitation are not infrequent.

Displacement for a long time is an important clue to recognize slow-moving slope geo-hazards (SMSGH). And active fault zones in Tibet Plateau are usually the regions developing serious SMSGHs because of rugged terrain, strong tectonic movement, frequent earthquakes and cracked rock masses, etc. Taking the persistent active Xianshuihe Fault (XSF) zone in the eastern Tibet Plateau as study area, this paper carries out time series InSAR observation using 18 periods of L-band ALOS/PALSAR datasets acquired from December, 2006 to September, 2010, gain millimetric-scale ground velocity. Furthermore, combining InSAR velocity with works of field investigation, optical remote sensing interpretation and geological setting analysis, we recognize 394 SMSGHs and gain some understanding of SMSGHs in types, deformation and spatial distribution. Firstly, creep landslide, debris flow and slow-moving moraine are three main types of SMSGH. Secondly, most paleo-landslides, co-seismic landslides and cracked unstable slopes distribute alone the northern section of XSF, and the majority of landslides intersecting with XSF is obviously movable and others are stable or of smaller movement. Thirdly, in the areas of debris flow source, the slow and disperse deformation commonly develop, which can be taken as the clue to identify debris flow; and two types of debris flow sources, “earth-forest” and “loose deposition,” are found. Finally, moraine in hanging glacier valley above 4200 m a.s.l. exists extensively, with huge body and fast dislocation, which is the majority surface erosion type nowadays in this uplifting plateau. The study results also indicate that the combination of InSAR displacement and geological setting analysis can recognize SMSGHs efficiently and effectively, being suitable for mountainous and inaccessible area as this study.

Efficient and accurate cement hydration simulation is an important issue for predicting and analyzing concrete&rsquo, s performance evolution. A large number of models have been proposed to describe cement hydration. Some models can simulate the test results with high accuracy by constructing reasonable functions, but they are based on mathematical regression and lack of physical background and prediction ability. Other models, such as the famous HYMOSTRUC model and CEMHYD3D model, can predict the hydration rate and microstructure evolution of cement based on its initial microstructure. However, this kind of prediction model also has some limitations, such as the inability to fully consider the properties of cement slurry, or being too complicated for use in finite element analysis (FEA). In this study, the hydration mechanisms of the main minerals in Portland cement (PC) are expounded, and the corresponding hydration model is built. Firstly, a modified particle hydration model of tricalcium silicate (C3S) and alite is proposed based on the moisture diffusion theory and the calcium silicate hydrate (C-S-H) barrier layer hypothesis, which can predict the hydration degree of C3S and alite throughout the age. Taking the hydration model of C3S as a reference, the hydration model of dicalcium silicate (C2S) is established, and the synergistic hydration effect of C3S and C2S is calibrated by analyzing the published test results. The hydration model of tricalcium aluminate(C3A)-gypsum system is then designed by combining the theory of dissolution and diffusion. This model can reflect the hydration characteristics of C3A in different stages, and quantify the response of the hydration process of C3A to different gypsum content, water&ndash, cement ratio, and particle size distribution. Finally, several correction coefficients are introduced into the hydration model of the main mineral, to consider the synergistic hydration effect among the minerals to some extent and realize the prediction of the hydration of PC.

This work employs a finite-element analysis of a chemo-thermal coupled concrete model that is clearly distinguishable from other models in the existing literature. Finite-element simulations are performed on both a macro- and mesoscale, with a mesoscopic mesh of random polygons generated by a Monte Carlo method. In order to link the two scales and identify their differences, a multi-scale framework based on a homogenisation scheme is adopted in the parameter studies. Macroscopic simulations are run on concrete samples with various water–cement ratios, and the outcomes are compared to experimental temperature curves, which show that the hydration model provides a relatively high accuracy. Mesoscopic thermo-chemical behaviours are accurately predicted for concrete samples with various volume fractions and aggregate compositions. The results show that the cooling conditions and the aggregate volume fraction and composition play a significant role in the chemo-physical process. The inhomogeneous distribution of hydration degree caused by the coarse aggregates in the concrete may lead to the presence of temperature gradients and slow the growth of cement strength, particularly in the areas where aggregates are concentrated.

We present a two-dimensional meso-scale finite element model for simulating the dynamic tensile behaviour of concrete. Aggregate, mortar and interface transition zone (ITZ) are explicitly modelled at the meso-scale. Rate-dependent cohesive elements, which take into account the effects of the viscosity occurring in the fracture process, are dispersedly pre-inserted to simulate the nucleation, coalescence, and propagation of cracks. The proposed model is validated by comparing with the experimental data of spall tests. The evolution of microcracks of concrete under dynamic loading is presented. The influences of the fracture parameters and the mesostructure on the dynamic tensile strength are investigated. The results suggest that the property of ITZ plays an important role on the dynamic tensile behaviour of concrete. The tensile strength and dissipated fracture energy under dynamic loading are affected by the mesostructure of concrete as well.

Correlation of blocks comprising the Pamir plateau with blocks in the Tibetan plateau is debated due to the complex tectonic history of amalgamated orogenic belts, followed by widespread Cenozoic intracontinental deformation within the Pamir plateau. Of particular interest is the Rushan-Pshart suture along the southern edge of the Central Pamir. It is uncertain if the suture zone is a Meso-Tethyan or a Paleo-Tethyan suture and if it is the western extension of the Bangong-Nujiang suture. This study presents new in-situ zircon U-Pb geochronology, whole-rock geochemistry, and Sr-Nd-Hf isotopes of three granitic plutons (Tahman, Tash, and Mingtie) along the southern edge of the Central Pamir block. Emplacement ages of the three plutons range from ~206 Ma to ~201 Ma. Samples from Tahman and Tash contain 67% to 76% SiO2, and yield A/CNK values between 0.92 and 1.17. They exhibit high LILE/HFSE ratios, negative Eu anomalies (Eu/Eu* = 0.41–0.77), pronounced negative Nb, Ta, P, and Ti anomalies, negative eNd(t) values (between −7.3 and −6.9), and negative zircon eHf(t) values (between −15.5 and −1.4). Geochemical data indicate that the Tahman and Tash samples represent metaluminous or peraluminous, I-type arc-related granitoids. The Tahman granites are inferred to have formed by partial melting of the Precambrian metaigneous and metasedimentary rocks in the lower crust, while the Tash pluton was formed by partial melting of the infracrustal medium-to-high K basaltic compositions within the garnet stability field of the lowermost crust. We suggest that these newly discovered Late Triassic granite plutons are related to the closure of the Rushan-Pshart suture. This is supported by recent geochronological, paleontological, and stratigraphic studies. Thus, the Rushan-Pshart suture is a Paleo-Tethyan suture. We further notice that the Central Pamir block is bounded by the Tanymas and Rushan-Pshart Paleo-Tethyan sutures to the north and south, respectively, which is structurally similar to the North Qiangtang and the Indochina blocks that are also bounded by two Paleo-Tethyan sutures from both sides. This indicates that the Central Pamir block is the western extension of the Tianshuihai-North Qiangtang block, both of which underwent oblique convergence during the closure of the Paleo-Tethys ocean.

Lithium halides are the important members of alkali halides with important industrial application. Here, we study the structural, elastic, electronic and optical properties of lithium halides, including LiF, LiCl, LiBr, and LiI, by using the first-principles calculations. The results of elastic constants and phonon spectra show that the calculated lithium halides are all mechanical and dynamical stability under ambient condition. Using the Voigt-Reuss-Hill method, we calculate shear moduli, bulk moduli and Young's modulus of LiF, LiCl, LiBr, and LiI compounds and they are all in the order of LiF > LiCl > LiBr > LiI. The calculated structural and mechanical parameters of LiF, LiCl, LiBr, and LiI compounds correspond well with the previous reported theoretical and experimental results. The electronic properties suggest that all the calculated lithium halides have wide direct gap with strong covalent bonding. The calculated optical properties indicate that LiI is the most suitable for the reflection of ultraviolet light.

By taking advantage of the separation characteristics of nonlinear gain and dynamic sector inside a Hammerstein model, a novel pole placement self tuning control scheme for nonlinear Hammerstein system was put forward based on the linear system pole placement self tuning control algorithm. And the nonlinear Hammerstein system pole placement self tuning control (NL-PP-STC) algorithm was presented in detail. The identification ability of its parameter estimation algorithm of NL-PP-STC was analyzed, which was always identifiable in closed loop. Two particular problems including the selection of poles and the on-line estimation of model parameters, which may be met in applications of NL-PP-STC to real process control, were discussed. The control simulation of a strong nonlinear pH neutralization process was carried out and good control performance was achieved.

Thermal analysis is one of the main components in the design and construction of mass concrete structures. A procedure for a heat-fluid coupling model (HFCM) is presented to simulate the thermal field of mass concrete with a pipe cooling system, which can accurately reflect the temperature gradient near the pipe and the temperature rise along the pipe. Additionally, to make it suitable for the simulation of forced-convection during pipe cooling, a modified particle swarm optimization (MPSO) method, based on particle migration is adopted for parameter identification of the Dittus–Boelter equation used by the heat-fluid coupling model, according to field tests. To verify the accuracy and computation efficiency of the method, a simplified 3D model is simulated and compared to other numerical models. Subsequently, the model is applied to the analysis of a monolith of the Dagangshan high arch concrete dam in the construction period. The actual climatic conditions, cooling pipe system, cooling schedule and thermal properties of the materials are considered in the analysis. The simulation results indicate that the proposed method can effectively simulate the cooling pipe state, water temperature rise along the flow, and directional changes of the flow in the thermal field of mass concrete. Moreover, the temperatures determined by the numerical simulation are in good agreement with the monitoring values. Findings in this research show that the proposed HFCM is feasible and has attractive advantages in the simulation of the thermal field in practical complex mass concrete engineering projects with cooling pipe systems.

PhoB is a response regulator of the PhoR/PhoB two-component signal transduction system that is involved in the regulation of the phosphate (Pho) regulon of Escherichia coli. PhoB has two domains, receiver domain and effector domain. The receiver domain can be phosphorylated by its cognate histidine kinase PhoR and the phosphorylation induces conformational changes of the full length protein of PhoB that promote the DNA binding and transcription. Three-dimensional crystal structures of PhoB receiver domain (PhoB

Transverse joint aperture is of certain reference value to ensure joint grouting quality and overall safety of high arch dam. A 3D isoparametric joint element model with spherical surface key grooves and finite thickness is used to simulate a transverse joint. A set of program is developed to simulate the transverse joint aperture of Dagangshan high arch dam. Combined with the measured temperatures, the whole developing process of Dagangshan arch dam’s transverse joint aperture is simulated. The real work behavior of transverse joint, thermal and mechanical properties of concrete, pouring process, joint grouting temperature and cantilever height of high arch dam are considered during the simulation. The simulation results show that the lower of the joint grouting temperature, the larger value of transverse joint aperture; the higher of cantilever height during the construction period, the smaller value of transverse joint aperture.

It is important and difficult to control the temperature of mass concrete structure during high arch dam construction. A new method with decision support system is presented for temperature control and crack prevention. It is a database system with functions of data storage, information inquiry, data analysis, early warning and resource sharing. Monitoring information during construction can be digitized via this system, and the intelligent analysis and dynamic control of concrete temperature can be conducted. This method has been applied in the construction of the Dagangshan Arch Dam in China and has proven to be very convenient. Based on the decision support of this system and the dynamic adjustment of construction measures, the concrete temperature of this project is well-controlled.

Thermal analysis is one of the main components in the design and construction of roller-compacted concrete dams. In this article, the heat-fluid coupling method is introduced to perform the thermal analysis of a pipe cooling system in mass concrete structures. Several typical models and examples are selected to verify the performance of this method. The proposed method is then applied to a roller-compacted concrete gravity dam called the Guandi Dam, which is still under construction in China. The actual climatic conditions and thermal properties of the materials are considered in this analysis. The temperatures determined by numerical simulation are in good agreement with the actual monitored values. The simulation results indicate that the proposed method can accurately simulate the cooling pipe state, the temperature rise along the water flow, and the effect of directional changes of flow in temperature distributions. Moreover, cracking is shown to more likely develop in concrete near the coolin...

Control of pH neutralization processes is challenging in the chemical process industry because of their inherent strong nonlinearity. In this paper, the model algorithmic control (MAC) strategy is extended to nonlinear processes using Hammerstein model that consists of a static nonlinear polynomial function followed in series by a linear impulse response dynamic element. A new nonlinear Hammerstein MAC algorithm (named NLH-MAC) is presented in detail. The simulation control results of a pH neutralization process show that NLH-MAC gives better control performance than linear MAC and the commonly used industrial nonlinear propotional plus integral plus derivative (PID) controller. Further simulation experiment demonstrates that NLH-MAC not only gives good control response, but also possesses good stability and robustness even with large modeling errors.

Pipe cooling systems are among the potentially effective measures to control the temperature of mass concrete. However, if not properly controlled, thermal cracking in concrete, especially near water pipes, might occur, as experienced in many mass concrete structures. In this paper, a new numerical approach to simulate thermal cracking based on particle flow code is used to shed more light onto the process of thermal crack propagation and the effect of thermal cracks on thermal fields. Key details of the simulation, including the procedure of obtaining thermal and mechanical properties of particles, are presented. Importantly, a heat flow boundary based on an analytical solution is proposed and used in particle flow code in two dimensions to simulate the effect of pipe cooling. The simulation results are in good agreement with the monitored temperature data and observations on cored specimens from a real concrete gravity dam, giving confidence to the appropriateness of the adopted simulation. The simulated results also clearly demonstrate why thermal cracks occur and how they propagate, as well as the influence of such cracks on thermal fields.

Today,foreign language learning becomes more and more important,but most people have no time learn it in school.Then many ones study foreign language in their freetime.Thus, good learning environment becomes important too. With the virtual communities are applied in study,they have improved the good learning environment The users in communities interact with each other through, communities provided an advanced level of a social network service combined with general aspects of a metaverse. They can explore, meet other users, socialize, participate in individual and group activities, create and trade items (virtual property) and services from one another. All of the content (buildings, scenery and people) is constructed by the users and so it has become a place where our imagination is given freedom to create and explore. All learning members(users) can learning freely and comfortably.

The ability of informal continuous education and training is important for today's professionals.Knowledge is outdated fast, so a professional has to continually update his/her experiences and knowledge profile, if they want to be competitive.In this paper we are interested in studying continuous education and training, in relation to Virtual Learning Communities(VLCs). The actual point varies from person to person. It is not casual learning, because it aims at a goal; and the goal has to do with the common interest of the VLC members. A user participates in a VLC which deals with his/her interest(s), either for professional reasons or as a hobby.

The flow sheet and operation principle of a liquid filling process was briefly discussed, and the dynamic simulation mathematic models of the filling process were developed in detail using the mass balance equations, gas state equations and historical process data. Based on the intelligent process control (IPC) simulation mode, the overall structure and the development scheme of the filling process simulation system was designed. A dynamic simulation system of the filling process was successfully developed, by taking a typical SCADA (supervisory control and data acquisition) configuration software named Century Star as GUI (graphical user interface) development platform, and integrating with a DLL (dynamic link library) function program to perform the calculation of the simulation models programmed using Visual C++. The development of the simulation GUI included the design and Command Language programming of simulated process flow sheet diagrams, simulation command buttons and their displaying diagrams, and the operation and parameters adjustment diagrams of all kinds of manipulators in the process flow sheets. The overall simulation operation of the filling process was fairly good achieved. Then some comprehensive and systematic simulation tests of the filling process were carried out. The simulation results show that the simulation system could satisfy the filling process research and design requirements very well, and the main process operation parameters were optimized through these simulation tests.

At present, China's economic development faces energy challenge, and the appropriate solution of energy bottleneck is the key to healthy, rapid and sustainable development. China's gross amount of hydraulic resource ranks first in the world; however, because of low level of development, hydraulic resource has a broad development prospect. Now, China's hydropower development is in its peak period. By the end of 2004, the gross installed hydropower capacity of China broke through 100 million kW. From there, it has remained in the top slot worldwide. The vigorous development of hydropower is necessary because of the energy shortage and environmental pollution in China in order to attain sustainable development of China's economy. Abundant hydraulic resource, huge market demands, the strategy of western development and the favorable environment of economic development provide hydropower construction with unprecedented advantages and opportunities. Chins hydropower development aims at an installed hydropower capacity of up to 194 million kW by 2010, accounting for 23.1% of the gross installed power capacity and 35% of hydropower resource. Finally, we present the general condition of Three Gorges project as well as the new mode of hydropower development of Three Gorges Project Corporation, i.e., cascade development.

This paper discusses the concept, level, and the teaching process of hybrid learning, and elaborates MOOCs and their features. Hybrid learning strategies are discussed. Based on flipped classroom, a hybrid learning strategy is proposed, where the design model are elaborated. An empirical research method is applied. It is shown that hybrid learning with the application of MOOC is feasible, and that a hybrid learning strategy based on flipped classroom can better stimulate students' interest and enthusiasm in learning.

Fly ash has been increasingly used in concrete structures due to both environmental and technical benefits. Despite significant past research, our understanding of thermal and physical properties of fly ash mortar and concrete remains incomplete and thus needs further investigation. This paper presents results of a study into important fundamental thermal and physical properties of both fly ash mortar and fly ash concrete. Replacement levels of Portland cement by fly ash investigated were30%, 50% and 60% by mass. In cement-fly ash mortar tests, increasing fly ash content was found to delay setting times, decrease both compressive and flexural strengths and reduce hydration heat. The effect of fly ash on hydration heat evolution of cement binder was quantitatively analysed. The obtained reduction coefficient (k) would allow reasonable prediction of temperature rise in concrete structures, which is of particular interest for mass concrete construction. In cement-fly ash concrete tests, thermal properties, including thermal diffusivity, conductivity and specific heat, were also measured and reported. There also appeared a linear relationship between compressive and flexural strengths of concrete incorporating up to 60% fly ash by mass. In addition, the observed effect of fly ash on ultimate tensile strain, static elasticity modulus and drying shrinkage of concrete was also reported.

The appearance of cracks exposed to severe environmental conditions can be critical for concrete structures. The research is to validate Particle Flow Code(PFC2D) method in the context of concrete thermally-induced cracking simulations. First, concrete was discreted as meso-level units of aggregate, cement mortar and the interfaces between them. Parallel bonded-particle model in PFC2D was adapted to describe the constitutive relation of the cementing material. Then, the concrete mechanics meso-parameters were obtained through several groups of biaxial tests, in order to make the numerical results comply with the law of the indoor test. The concrete thermal meso-parameters were determined by compared with the parameters in the empirical formula through the simulations imposing a constant heat flow to the left margin of concrete specimens. At last, a case of 1000mm×500mm concrete specimen model was analyzed. It simulated the formation and development process of the thermally-induced cracks under the cold waves of different durations and temperature decline. Good agreements in fracture morphology and process were observed between the simulations, previous studies and laboratory data. The temperature decline limits during cold waves were obtained when its tensile strength was given as 3MPa. And it showed the feasibility of using PFC2D to simulate concrete thermally-induced cracking.

With the development of wireless mobile communication, more and more wireless data services have gradually emerged, calling for effective pricing mechanism due to the nonapplicable traditional one. In this paper, a novel hybrid Diff-SerV pricing method for wireless data services is proposed, which considers radio resources, service characteristics as well as quality of service (QoS). The kernel of our algorithm is to distinguish service types and related the resource cost with QoS level. Therefore, it could be viewed as a method for resources scheduling, which can effectively exploit the scare radio resources to support more service users and meanwhile provide better QoS.

China's gross amount of hydraulic resource ranks first in the world; however, at present, China's economic development faces energy bottleneck. Huge market demands, as well as the strategy of western development, provide hydropower with an opportunity and a broad development prospect. At the same time, some negative influence on environment and ecology also give hydropower development with unprecedented challenges. However, development of hydropower is necessary because of the energy shortage and environmental pollution in China in order to attain sustainable development of China's economy. Finally, we present the typical example of Three Gorges project as hydropower development.

New methods for high concrete dam cooling by water flowing were introduced in this article. The heat-fluid coupling model, which can better simulate disposition of cooling pipe and water temperature rise along the flow, will bring more accurate simulation results of temperature field. The nonlinear creep model can better reflect the nonlinear relation between concrete creep and stress ratio of concrete. The temperature space-time dynamic control method, improving from the traditional multi-stages water cooling method, can optimize the process of temperature drop and thus decrease the thermal stress. And the computation results of high concrete dams (Guandi, Wanjiakouzi and Jinping-1 in China) show that the temperature by numerical are lit the actual monitor values. New methods of temperature simulation presented in this paper for high concrete dam will have good application prospect in practical project.