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Microbial-induced calcite precipitation (MICP) techniques are promising solutions for repairing cracks in reinforced concrete (RC) structures when exposed to a harsh chloride environment. By means of the lattice network method, this study numerically investigates the entire MICP-induced healing process from crack closure to inhibition of chloride transport of the microbial self-healing concrete by coupling the following two models: (1) the crack self-healing model; and (2) chloride diffusion model. The crack self-healing model provides visualization of the reduction of local crack widths induced by MICP. The chloride concentration distribution is quantitatively reflected through the chloride diffusion model. In addition, an empirical formula is employed to represent the relationship between diffusion coefficients of cracks in the chloride diffusion model and the time-varying crack width obtained from the crack self-healing model. The reduction of crack widths and the distribution of chloride within microbial self-healing concrete are determined through numerical calculations. The simulation reliability is validated based on comparisons with the available literature. Simulation results demonstrate that the MICP-induced crack healing effectively impedes chloride transport. [ABSTRACT FROM AUTHOR]

Scientifically validating the value of rural heritage and exploring construction wisdom has emerged as a significant challenge in the study of rural settlements worldwide. Rural heritage shows significant differences according to the natural environment, history, culture, and socio-economic factors. However, the assessment of the authenticity and effectiveness of heritage values have yet to be quantified due to the difficulty in obtaining evidence directly from samples. By constructing a multi-dimensional model of villages for quantitative analysis, we proposed a multifaceted spatial visibility analysis method based on individual and combined defense structures to empirically study the remains of eight towers in Moluo village, western China. This study demonstrated that towers serve as regional defense structures and are essential for constructing a comprehensive and effective visual defensive system (VDS) in Moluo village, a typical military defense village. The effectiveness and coverage of the towers vary depending on their location, height, type, and other factors. They form a complementary and synergistic relationship, playing a dual mechanism of public and private, local and overall defense. In summary, this method enables the feasible quantification and analysis of the functional value of rural heritage through landscape visual analysis. It provides a new perspective for studying the authenticity of heritage functions. [ABSTRACT FROM AUTHOR]

Self-consolidating concrete (SCC) may experience autogenous and drying shrinkage due to a high content of cementitious materials, lower aggregate content, and smaller aggregate size, resulting in concrete cracking and other durability issues. In order to solve these problems, shrinkage-reducing materials have been proposed and studied, such as polypropylene fiber, lightweight fine aggregate, and expansive admixtures. However, investigation of the combined effect of the aforementioned three shrinkage-reducing materials on SCC is still unreported. This study examined the influence of polypropylene fiber (0.05%, 0.1%, 0.15% of the volume of the concrete), prewetted lightweight aggregate (10%, 20%, 40% of the volume of the fine aggregate), and expansive agent (0%, 8% of the cementitious materials weight) on the shrinkage of concrete during a seven-day curing period under two curing conditions, sealed cure and top-surface exposure cure. The results showed that it was more effective to mitigate early age shrinkage by adding lightweight aggregate alone than by adding polypropylene fiber alone. In the sealed cure (S-Cure) condition, adding 10% lightweight aggregate compensated for shrinkage, and 0.1% polypropylene fiber content exhibited the highest shrinkage reduction. With the top-surface exposure cure (TE-Cure) condition, 20% lightweight aggregate compensated for shrinkage, and 0.15% content polypropylene fiber showed the highest shrinkage mitigation. It showed that the shrinkage of concrete, which has low polypropylene (PP) fiber content (0.05% and 0.10%) and no expansive agent added, was decreased with the increase of lightweight aggregate content. At a high content of PP fiber of 0.15%, the incorporation of lightweight aggregate did not exhibit significant influence on shrinkage reduction. [ABSTRACT FROM AUTHOR]

Soil moisture is an important component of the soil–vegetation–atmosphere terrestrial hydrological cycle and is an important factor affecting terrestrial ecosystems. In the context of extensive vegetation greening on the Tibetan Plateau (TP), it is important to investigate the effect of vegetation greening on soil moisture to maintain ecosystem stability and protect the sustainability of ecological restoration projects. To evaluate the effect of vegetation greening on soil moisture on the TP, the spatial distribution and trends of soil moisture and vegetation on the TP were analyzed using GIMMS NDVI data and ERA5 soil moisture data from 1982 to 2015. The effects of grassland NDVI, precipitation, and temperature on SM were also explored using multiple regression apparent and SEM. The main results are as follows: from 1982 to 2015, both grassland NDVI and SM showed a stable increasing trend. Precipitation was the most important factor influencing SM changes on the TP. In the context that vegetation greening is mainly influenced by temperature increase, vegetation plays a dominant role in SM changes in soil drying and soil wetting zones. In this paper, the climate–vegetation–soil moisture coupling mechanism of grasslands on the TP is investigated, and the related results can provide some theoretical references and suggestions for global ecosystem conservation and the sustainable development of ecological restoration projects. [ABSTRACT FROM AUTHOR]

Background: Burkholderia pseudomallei (B. pseudomallei), as a highly pathogenic organism, causes melioidosis, which is a disease of public health importance in many tropical developing countries. Here, we present and validate a novel detection technique, termed multiple cross displacement amplification combined with nanoparticles-based lateral flow biosensor (MCDA-NB), for identifying B. pseudomallei and diagnosing melioidosis. Results: B. pseudomallei-MCDA targets the TTS1 (Type III secretion system gene cluster 1) to specifically design ten MCDA primers. The nanoparticles-based biosensor (NB) can be combined with B. pseudomallei-MCDA for visually, objective, simply and rapidly reporting reaction results. The optimal amplification conditions of B. pseudomallei-MCDA were 66 °C for 30 min. Assay's sensitivity was 100 fg of genomic DNA in the pure cultures, and the analytical specificity was 100% by the examination of 257 strains, including 228 B. pseudomallei and 29 non-B. pseudomallei. As a result, the whole detection procedure was completed within 50 min, including 15 min for genomic DNA preparation, 30 min for l MCDA reaction, and 2 min for the interpretation of the results visually by biosensor. Conclusions: B. pseudomallei-MCDA assay is a rapid, sensitive and specific method for the detection of B. pseudomallei, and can be used as a potential tool for melioidosis diagnose in basic, field and clinical laboratories. [ABSTRACT FROM AUTHOR]

The involvement of aberrantly expressed genes in the pathogenesis and progression of various human malignancies has been widely reported, including clear cell renal cell carcinoma (ccRCC). This study aimed to identify potential crucial genes in ccRCC and further investigate the role of these genes in ccRCC prognosis. Three gene expression profiles (GSE3, GSE6344 and GSE53000) were downloaded from GEO database. GEO2R was performed to identify the differentially expressed genes (DEGs) between ccRCC and normal samples. GO analysis and KEGG pathway enrichment analysis were applied for the function analysis. The DEGs were mapped into the PPI network, then the hub genes were identified and verified using the ONCOMINE database. Kaplan–Meier plotter was used to evaluate of the prognostic value of the identified hub genes. A total of 113 DEGs were identified from the three gene expression profiles, including 64 up-regulated genes and 69 down-regulated genes. DEGs were observed to be enriched in biological processes related to the progress and pathogenesis of human cancers. According to PPI network, 5 hub genes were collected, including TYROBP, C1QB, ITGB2, CD53 and FCER1G. Among them, CD53 was newly identified, and Kaplan–Meier survival curves suggested that high expression of CD53 was significantly associated with poor survival in ccRCC patients (log-rank P < 0.01). The present results may provide new insight into the understanding of molecular mechanisms and the clinical prognosis of ccRCC. [ABSTRACT FROM AUTHOR]

Evaluation of the concrete cracking induced by rebar corrosion is necessary for accurately clarifying the durability and predicting the service life of reinforced concrete (RC) structures. The fact that rust penetration into cracks might decrease corrosion expansion has been realized but not sufficiently investigated. In this paper, a numerical approach in terms of the mesoscopic structure of concrete is used to simulate the corrosion-induced concrete cracking, and the lattice network model to account for rust penetration into cracks is developed by assuming that the movement of rust is driven by moisture convection. The total rust amount is calculated based on Faraday's law, and the rust expansion is transformed to a radial displacement boundary condition for both uniform and nonuniform conditions. Rust penetration is assumed to be a convection process governed by Darcy's law. The proposed model is confirmed by comparing cracking pattern, corrosion pressure, surface crack width, mass ratio of penetrated rust to total rust (ΔWpe/ΔWtotal), and volume ratio of cracks occupied by rust to total cracks (Vrustcrack/Vcracktotal) with available experimental and numerical results. It is found that the distribution and the amount of penetrated rust are closely related to the volume of cracks and the connection of crack networks. Besides, through sensitivity analysis of influencing factors for rust penetration, it is found that a higher dissolved degree of rust in moisture induces a higher ΔWpe/ΔWtotal , but it doesn't influence Vrustcrack/Vcracktotal. A larger relative water content at the concrete-steel interface will induce higher ΔWpe/ΔWtotal and Vrustcrack/Vcracktotal , while the initial relative water content in concrete has no significant difference on either ΔWpe/ΔWtotal or Vrustcrack/Vcracktotal. [ABSTRACT FROM AUTHOR]

In this study, a spring–mass physical model is proposed to study the complex band structure of a one-dimensional parity-time (PT)-symmetric local resonant phononic crystal. By solving the kinetic equations, the analytical solutions of the dispersion relation and effective mass are obtained. As is known, the infinite effective mass would appear at the resonant frequency in a Hermitian system without any gain or loss. Once the balanced gain and loss are added to form a PT-symmetric system, the infinite effective mass would become finite, and the exceptional points can be observed in the subwavelength realm. With the increase in gain and loss, exceptional points would coalesce and form a higher order one. The numerical simulations in a practical structure agree well with the analytical analysis. In addition, the simulated transmission/reflection spectrum and field distribution clearly demonstrate the anisotropic transmission resonances. Our investigation enriches the physical connotation of local resonant phononic crystals in non-Hermitian systems. [ABSTRACT FROM AUTHOR]

Catalytic membranes supported with nano-catalysts have been widely used for wastewater treatment. The traditionally catalyst immobilization methods, such as physical blending, chemical deposition and impregnation et al., involve complex preparation steps. Herein, Ag nanoparticles were in-situ immobilized on a ceramic microfiltration substrate by a mussel-inspired facile metallization process. Firstly, dopamine was deposited onto the substrate (∼200 nm) to form a uniform polydopamine coating. Then, Ag nanoparticles were in-situ metalized and immobilized on the polydopamine decorated ceramic membrane. The preparation conditions were relatively simple without sintering. FTIR, XRD, FESEM and EDS characterizations demonstrate the successful immobilization of the Ag nanoparticles. The obtained membrane exhibits good hydrophilicity and permeability (606.08 L m−2 h−1 at 0.1 MPa). The degradation rate of methyl orange achieves ∼95.6% within 20 min. The apparent reaction rate constant reaches the highest value of 568.1 min−1 at 0.5 MPa, which is several orders of magnitude higher than that of the feed side. The composite membrane can degrade mixed dyes. The catalytic membrane also shows excellent stability and antifouling property. In conclusion, this research provides a convenient and effective way for preparing a kind of composite catalytic membrane with high performance, which has potential applications in environmental remediation. [Display omitted] • Mussel-inspired in-situ metallization and loading of nano-Ag on ceramic membrane. • The optimal mineralization time of nano-Ag is 2 h. • Ag nanoparticles (∼ 12 nm) tightly packs everywhere on the substrate surface. • Superior catalytic activity of the membrane in treating dye wastewater. • Excellent stability and antifouling property of the membrane. [ABSTRACT FROM AUTHOR]

Background: In computational biology, the physical mapping of DNA is a key problem. We know that the double digest problem (DDP) is NP-complete. Many algorithms have been proposed for solving the DDP, although it is still far from being resolved. Results: We present DDmap, an open-source MATLAB package for solving the DDP, based on a newly designed genetic algorithm that combines six genetic operators in searching for optimal solutions. We test the performance of DDmap by using a typical DDP dataset, and we depict exact solutions to these DDP instances in an explicit manner. In addition, we propose an approximate method for solving some hard DDP scenarios via a scaling-rounding-adjusting process. Conclusions: For typical DDP test instances, DDmap finds exact solutions within approximately 1 s. Based on our simulations on 1000 random DDP instances by using DDmap, we find that the maximum length of the combining fragments has observable effects towards genetic algorithms for solving the DDP problem. In addition, a Maple source code for illustrating DDP solutions as nested pie charts is also included. [ABSTRACT FROM AUTHOR]

Abstract Objectives High mobility group box 1 protein (HMGB1) is an important late inflammatory mediator in the body. In recent years, studies have found that it plays an important pathogenic role in various diseases such as sepsis. However, it is unclear whether the genetic variation of the HMGB1 gene is related to the susceptibility to sepsis. This study investigated the relationship between susceptibility and outcome of the HMGB1 gene rs2249825, rs1045411, and rs1360485 single nucleotide polymorphisms (SNPs) in Chinese Han patients with sepsis. Methods The HMGB1 gene rs2249825, rs1045411, and rs1360485 genotypes were detected by the direct sequencing method in 345 patients with sepsis and 345 healthy controls. Serum HMGB1 levels were measured by enzyme-linked immunosorbent assay (ELISA). Results The HMGB1 gene rs2249825 and rs1045411 site SNPs were associated with sepsis risk, but the rs1360485 site SNP was not associated with sepsis risk. Subjects with the HMGB1 gene rs2249825 and rs1045411 site mutations had higher serum HMGB1 levels, and patients with mutant genotype sepsis had higher APACHE II scores and lower 30-day survival rates. There were no correlations among the rs1360485 site SNP, sepsis risk, and patient 30-day survival. Conclusion The HMGB1 gene rs2249825 and rs1045411 site SNPs are associated with susceptibility and outcomes of Chinese Han patients with sepsis. The rs2249825 locus C allele and the rs1045411 locus A allele are high risk factors for sepsis and severity in the Chinese Han population, and are associated with adverse outcomes in patients with sepsis. Highlights • The HMGB1 gene rs2249825 and rs1045411 site SNPs are associated with susceptibility and outcomes of Chinese Han patients with sepsis. • Subjects with the HMGB1 gene rs2249825 and rs1045411 site mutations had higher serum HMGB1 levels. • The rs2249825 locus C allele and the rs1045411 locus A allele are high risk factors for sepsis and severity in the Chinese Han population, and are associated with adverse outcomes in patients with sepsis. [ABSTRACT FROM AUTHOR]

As one of the promising information-centric networking (ICN) architectures, NDN has attracted tremendous research attention and effort in the past decade. In particular, security and privacy remain significant concerns and challenges due to the fact that most of the traditional cryptographic primitives are no longer suitable for NDN architecture. For example, the traditional cryptographic primitives aim to secure point-to-point communications, always requiring explicit descriptions of to where or whom the data packets are intended, while network addressing or locating in NDN becomes implicit. To deal with such issues, the recently developed cryptographic primitives such as ABE have been applied to NDN. Also, to efficiently solve the trust-roots problem and seamlessly deploy cryptographic infrastructures, the concept of SDN has been introduced to NDN as well. This tutorial is devoted to exploring the interesting integration between NDN, ABE, and SDN. [ABSTRACT FROM AUTHOR]

The security of several fully homomorphic encryption (FHE) schemes depends on the intractability assumption of the approximate common divisor (ACD) problem over integers. Subsequent efforts to solve the ACD problem as well as its variants were also developed during the past decade. In this paper, an improved orthogonal lattice (OL)-based algorithm, AIOL, is proposed to solve the general approximate common divisor (GACD) problem. The conditions for ensuring the feasibility of AIOL are also presented. Compared to the Ding–Tao OL algorithm, the well-known LLL reduction method is used only once in AIOL, and when the error vector r is recovered in AIOL, the possible difference between the restored and the true value of p is given. Experimental comparisons between the Ding-Tao algorithm and ours are also provided to validate our improvements. [ABSTRACT FROM AUTHOR]

Catalytic membranes containing metal nano-catalyst are widely used in dye wastewater treatment. Comparing to the traditional catalyst loading methods, such as the co-precipitation, the surface grafting, and impregnation et al., hydrothermal method is simple, and the crystals obtained have a uniform distribution and high purity. In this study, CuO nano-catalysts is immobilized on ceramic substrate by hydrothermal method. The prepared membrane is used to activate persulfate (PMS) for the degradation of azo dyes. FTIR, XPS, XRD, and FESEM characterizations prove that CuO is successfully loaded onto the Al2O3 substrate, the optimal loading amount is 0.03 g/cm2. Static degradation experiments show that the composite membrane could degrade 85% of the Congo red within 80 min. In the dynamic degradation process, the degradation efficiency is further improved to a maximum of 96.8% within 80 min, and the permeation flux of catalytic membrane is relatively stable during the degradation process. In long-term experiments, the degradation efficiency still remains at ~ 87% after 4 cycles, indicating good stability. Quenching experiment shows that the main oxidizing radicals are sulfate radical. In conclusion, the prepared membrane can activate PMS efficiently, which has a potential applications in dye wastewater treatment. [ABSTRACT FROM AUTHOR]

There are more large-scale photovoltaic (PV) plants being established in rural areas due to availability of low-priced land. However, distribution grids in such areas traditionally have feeders with low X/R ratios, which makes the independent reactive power compensation method less effective on voltage regulation. Consequently, upstream step voltage regulator (SVR) may suffer from excessive tap operations with PV-induced fast voltage fluctuations. Although a battery energy storage system (BESS) can successfully smooth PV generation, frequent charge/discharge will substantially affect its cost effectiveness. In this paper, a real-time method is designed to coordinate PV inverters and BESS for voltage regulation. To keep up with fast fluctuations of PV power, this method will be executed in each 5 s control cycle. In addition, charging/discharging power of BESS is adaptively retuned by an active adjustment method in order to avoid BESS premature energy exhaustion in a long run. Finally, through a voltage margin control scheme, the upstream SVR and downstream PV inverters and BESS are coordinated for voltage regulation without any communication. This research is validated via a real-time digital simulator MatLab cosimulation platform, and it will provide valuable insights and applicable strategies to both utilities and PV owners for large-scale PV farm integration into rural networks. [ABSTRACT FROM PUBLISHER]

• A method of using pinned connection and unbonded posttensioning strands (UPSs) to mutually improve the collapse-resistant performance of precast concrete structures was proposed in this study. • The pinned connections are used for connecting precast beams with columns at the precast beam ends, and UPSs with straight profile are placed at the bottom of beam cross-section. • In order to investigate whether the proposed method can enhance collapse-resistant capacity of precast concrete structures, static progressive collapse tests were conducted for the newly proposed precast concrete frame substructures with UPSs (UPPC frame substructures) and without UPSs (PC frame substructure). • Influences of effective prestress level upon the collapse-resistant capacity of UPPC substructure were investigated. • Three-dimensional finite element models (FEMs) was developed to simulate the progressive collapse behavior of the tesed UPPC and PC substructures by using ABAQUS software. In precast concrete frame structures, it is imperative that beam-to-column connection has appropriate robustness and reliable axial resistance to defense against progressive collapse. Hence, a method of using pinned connection and unbonded posttensioning strands (UPSs) to mutually improve the collapse-resistant performance of precast concrete structures was proposed in this study. The pinned connections are used for connecting precast beams with columns at precast beam ends, and UPSs with straight profile are placed at the bottom of beam cross-section. In order to investigate whether the proposed method can enhance collapse-resistant capacity of precast concrete structures, static progressive collapse tests were conducted for the newly proposed precast concrete frame substructures with UPSs (UPPC frame substructures) and without UPSs (PC frame substructure). Moreover, influences of effective prestress level upon the collapse-resistant capacity of UPPC substructure were also investigated. Test results demonstrated that, similar to conventional RC frame structure, the compressive arch action (CAA) and catenary action (CTA) could also develop in the proposed UPPC substructures to avert progressive collapse. The UPPC substructure was able to develop 32% higher CAA capacity and 162% larger CTA capacity as compared to the PC substructure, indicating that the UPSs play a positive role in enhancing both its CAA and CTA. The CTA capacity of the PC substructure was 53.8% higher than that of CAA, which signifies that the pinned connection can be employed to improve structural robustness to mitigate progressive collapse. In addition, the increase of effective prestress level of UPSs is beneficial to the enhancement of CAA capacity of the UPPC substructure. However, higher effective prestress level is limited to improve its CTA capacity due to lower deformation capacity of UPSs. Subsequently, three-dimensional finite element models (FEMs) of the UPPC and PC substructures were developed by using ABAQUS software. By comparing experimental data with FEM results, it was concluded that the FEM could accurately predict the load–displacement curves, crack patterns and reinforcing ruptures of all the test specimens. [ABSTRACT FROM AUTHOR]

An ultrathin and uniform Sm 2 O 3 rare earth oxide functional coating is formed to enhance the lithium storage performance of high-voltage medium-nickel low-cobalt LiNi 0.6 Co 0.05 Mn 0.35 O 2 cathode. The multi-electron rare earth oxide functional coating improves electrode–electrolyte interfacial stability and bulk structural stability by acting as a physical passivation layer and charge compensation payer. [Display omitted] • An ultrathin and uniform Sm 2 O 3 rare earth oxide functional coating is obtained. • Sm 2 O 3 coating acts as a physical passivation layer and charge compensation payer. • Multi-electron Sm 2 O 3 coating enhances the interfacial lattice oxygen stability. • The interfacial, thermal, and bulk structural stability are improved. • An excellent high-voltage medium-nickel low-cobalt LiNi 0.6 Co 0.05 Mn 0.35 O 2 cathode. High-voltage medium-nickel low-cobalt lithium layered oxide materials have been recognized as a kind of promising cathodes to further promote the energy density of lithium-ion batteries (LIBs) due to their relatively high capacity, low cost, and improved safety. However, the high voltage induced bulk structure degradation and interfacial environment deterioration limit the performance liberation of this kind of cathodes. Here, an ultrathin and uniform Sm 2 O 3 rare earth oxide functional coating has been introduced to enhance the lithium storage performance of LiNi 0.6 Co 0.05 Mn 0.35 O 2 (NCM) cathode. On the one hand, this multi-electron Sm 2 O 3 function coating could increase the activation energy of surface lattice oxygen loss, improving the electrode–electrolyte interface stability; on the other hand, it delays the phase transition temperature and weakens the harmful H3 phase transition of NCM, improving its thermal stability as well as minimizing the mechanical degradation. These beneficial effects endowed by the Sm 2 O 3 coating imply that it could behave as both a physical passivation layer and a charge compensation payer. As a result, the 2%-Sm 2 O 3 @NCM delivers a higher capacity retention rate (97.3% vs 75.0% after 150 cycles) and a superior rate capacity (117 mAh g−1 vs 52 mAh g−1 at 5C) than the pristine NCM, making high-voltage lithium layered oxide one step closer to being a viable cathode. [ABSTRACT FROM AUTHOR]

As a kind of unwelcome, unavoidable, and malicious behavior, distributed denial of service (DDoS) is an ongoing issue in today’s Internet as well as in some newly conceived future Internet architectures. Recently, a first step was made towards assessing DDoS attacks in Named Data Networking (NDN)—one of the promising Internet architectures in the upcoming big data era. Among them, interest flooding attack (IFA) becomes one of the main serious problems. Enlightened by the extensive study on the possibility of mitigating DDoS in today’s Internet by employing micropayments, in this paper we address the possibility of introducing economic levers, say, dynamic pricing mechanism, and so forth, for regulating IFA in NDN. [ABSTRACT FROM AUTHOR]

[Display omitted] • Age of the Mengyejing potash deposit is mid-Cretaceous time. • Most Cretaceous detrital zircons were mostly derived from volcano eruptions. • The Mengyejing have deposited earlier than the Khorat potash deposit by 20–25 Ma. The age of the Mengyejing potash deposit (MPD) in the Simao Basin, the only pre-Quaternary economically exploitable solid potash occurrence in China, has been the subject of debate for decades. It has been established that the ore-hosting Mengyejing Formation formed during the mid-Cretaceous based on radioactive and magnetic dating. The age discrepancy between the primary mid-Cretaceous and the squeezing of the Middle Jurassic is related to the lack of direct previous dating of the MPD itself. In this study, detrital zircon U-Pb dating of four clastic rock samples interbedded with the potash layers yielded the youngest zircon ages of 104.8, 106.5, 107.8, and 110 Ma. Taking into account the relatively large proportion of the youngest Cretaceous zircons and the Hf isotopic analysis, we propose that most of the Cretaceous zircons were derived from the contemporaneous volcanic activity that produced the tuff beds within the potash deposit and elsewhere in the Mengyejing Formation, while only a small fraction of the Cretaceous zircons were found to be of detrital origin and have derived from the Bomi-Chayu and Dianxi-Burma batholiths. Consequently, the maximum age of the potash deposit of 110 to 105 Ma is the true depositional age of the strata and potash deposit. [ABSTRACT FROM AUTHOR]

The canonical structure of DNA has four bases – Thymine (T), Adenine (A), Cytosine (C), and Guanine (G) – and DNA codes are regarded as words over the alphabet set Σ = { A , C , G , T } , satisfying certain combinatorial conditions. Good DNA codes are desirable for DNA computation, DNA microarray technologies and molecular barcodes, etc. One of the main tasks in DNA code designing is to build more codewords and better GC -content for given fixed word length n . Existing heuristic methods work well for small n . In this paper, we present a systematic method for constructing good DNA codes for large n by using irreducible cyclic codes. Being different from traditional DNA constructions, our method is based on algebraic number theory rather than classical heuristic algorithms and the conventional coding theory. Furthermore, comparing with the traditional DNA codes, our codes have larger number of codewords and better GC -content. As far as we know, it is the very first time to utilize irreducible cyclic codes for constructing a type of DNA codes. [ABSTRACT FROM AUTHOR]

In this study, the stochastic sampled‐data approach is developed to deal with the H∞ control problem for a class of linear multi‐agent systems. For each agent, signals should be transmitted to the control input, including not only its own measurements, but also the output information received from the neighbour agents. The relationships of information communications between the whole multi‐agents are totally reflected by a weighted directed graph with a fixed topology structure. To the addressed problem, the author's focus is to design an output feedback controller for each agent such that, for the external energy bounded disturbances, the exponential stability in the mean square sense and interference rejection ability under consideration can be guaranteed. By assuming that the sampling period of each agent switches between two values in a probabilistic way, the stochastic sampling phenomenon is well characterised in every sampling tasks. In virtue of Lyapunov theory and semi‐definite programming method, sufficient conditions are derived to ensure the exponential stability as well as H∞ performance, and the feedback controllers are also designed by solving some certain matrix inequalities. Finally, a numerical simulation is given to demonstrate the validness of the proposed control strategy. [ABSTRACT FROM AUTHOR]

Abstract: For understanding the monosodium aluminate hydrate crystallization from the supersaturated aluminate solution containing red mud as the leaching liquor of bauxite, the liquid–solid–solid dispersion of a simulant system, i.e. glycerite, red mud and sand, in a stirred reactor has been experimentally investigated as well as simulated using computational fluid dynamics model (CFD) for the first time. The computational model is based on the Eulerian multi-fluid model along with RNG k–ε turbulence model, where Syamlal–obrien-symmetric drag force model () of the inter-phase momentum transfer between two dispersed solid phases is taken into account. A good agreement is obtained between the experimental data of solid distributions and the simulation results in the flow fields of liquid–solid–solid as well as liquid–solid systems. The solid suspension qualities of both liquid–solid and liquid–solid–solid systems in the stirred reactors with and without draft tube were also studied in detail based on mixing time, the standard deviation of solid concentration proposed by , the flow pattern and power number. The influence of the interaction between two dispersed solid phases on the suspension of red mud is found significantly greater than that of sand. The holdup of sand below the impeller is considerably larger than that above the impeller and the red mud dispersion approaches homogeneous in the reactor. The mixing time of liquid–solid–solid suspension is longer than that of liquid–solid suspension under the same conditions, and the mixing times of both systems in the stirred reactor with draft tube are longer than that in the reactor without draft tube. Furthermore, the distributions of sand and red mud in the reactor with draft tube were found less homogeneous than those without draft tube in most cases. [Copyright &y& Elsevier]

Abstract: This paper presents an improved impossible differential cryptanalysis of SAFER ciphers, which uses the miss-in-the-middle technique developed by Biham et al. We analyze 3.75-round SAFER SK-64, [1] (In this paper, the number in the name of the ciphers indicates the key length). 1 using chosen plaintexts, bytes memory and half round computations. Furthermore, the new impossible differential attack on 3.75-round SAFER+/128 uses chosen plaintexts, half round computations and bytes memory. And attack on 3.75-round SAFER++/128 uses data, time, and memory. [Copyright &y& Elsevier]

Abstract: Two kinds of carbon nanotubes (CNTs) with different inner diameter (less than 10nm: CNTs-1 and between 60 and 100nm: CNTs-2) were used as catalyst supports. The platinum particles were simply deposited on the outside surface (CNTs-1) and inside (CNTs-2) and were easily reduced to Pt0 by refluxing. The catalysts exhibit high activities in the selective hydrogenation of cinnamaldehyde which contains both Ce:glyph name="dbnd" />O bonds. But the selectivity of these two catalysts was quite different under same reaction conditions. The high selective hydrogenation of Cs observed over catalyst 3%Pt/CNTs-2, while the completely hydrogenation of both Ce:glyph name="dbnd" />O bonds was found over catalyst 3%Pt/CNTs-1. [Copyright &y& Elsevier]

Inorganic membrane has good stability, which acts as a significant role in water treatment. However, the effective preparation of stable and defect-free nanofiltration membranes on inorganic substrate remains challenge. In this paper, ceramic supported composite nanofiltration membrane (CNM) was prepared by mineralization of TiO 2 polymeric sol induced by a polydopamine (PDA) interlayer on ceramic ultrafiltration substrate at low temperature. FESEM analysis shows that a PDA interlayer with a thickness of ∼44 nm and a smooth and dense top layer with a thickness of ∼88 nm are formed. And the construction and chemical changes of the membrane layer are confirmed by XPS and FTIR analyses. The water contact angle and zeta potential characterizations show that the CNM has a hydrophilic surface and a positive charge property. The obtained CNM has a polyethylene glycol (PEG) molecular weight cut-off (MWCO) of 800 Da. The CNM prepared with polymeric sol size less than 10 nm has a higher rejection to divalent salt. At 0.6 MPa, the CaCl 2 rejection is 91.5% and the permeation flux is 22.8 L m−2 h−1. In 50 h continuous filtration, the rejection rate changes little. This paper describes a facile and efficient approach for producing stable ceramic supported composite nanofiltration membranes, which has potential applications in water treatment. [ABSTRACT FROM AUTHOR]

Evaporites are widely distributed within continental "red beds" in the Lanping–Simao Basin, west Yunnan, China. Sr (Strontium), S (Sulfur), and O (Oxygen) isotope compositions have been measured on 54 sulfate or/and sulfate-bearing samples collected from Lanping, Nuodeng, Jinggu, Mengyejing, Baozang throughout the Lanping–Simao Basin. The 87Sr/86Sr ratios of all samples (0.708081 to 0.710049) are higher than those of contemporaneous seawater, indicating a significant continental contribution to the drainage basin. Sulfates in the Lanping Basin have higher 87Sr/86Sr ratios (0.709406 to 0.710049) than those (0.708081 to 0.709548) in the Simao Basin. Nevertheless, the δ34S values of gypsums (13.4‰ to 17.6‰) in Lanping and Baozang fall within the range of Cretaceous seawater. Gypsums from a single section in Baozang have trends of decreasing δ34S values and increasing 87Sr/86Sr ratios from base to top, indicating continental input played an increasingly significant role with the evaporation of brines. High δ34S values (20.5‰ to 20.7‰) of celestites in Lanping are probably caused by bacterial sulfate reduction (BSR) process in which 34S were enriched in residual sulfates and/or recycling of Triassic evaporites. The reduced δ34S values of gypsums (9.5‰ to 10.4‰) in Nuodeng could have been caused by oxidation of sulfides weathered from Jinding Pb-Zn deposit. The complex O isotope compositions indicate that sulfates in the Lanping–Simao Basin had undergone sulfate reduction, re-oxidation, reservoir effects, etc. In conclusion, the formation of continental evaporites was likely derived from seawater due to marine transgression during the Cretaceous period. Meanwhile, non-marine inflows have contributed to the basin significantly. [ABSTRACT FROM AUTHOR]

• The analytical models to predict the reverse arch action (RAA) and the compressive arch action (CAA) of unbonded prestressed RC beam column sub-assemblages under column removal scenarios were proposed. • A notional eccentricity was introduced for calculating the additional bending moment of beam section. • Comparisons between the experimental and FEM's results indicated that the FEM gave good predictions of CAA capacity of conventional RC beam column sub-assemblages. • The effects of effective prestress, size of beam section, stiffnesses of end support restraints and span of the beam on the RAA capacity and the inverted camber can be reflected in the RAA model. • The augmentation of effective prestress is advantageous to the enhancement of CAA capacity of UPRC sub-assemblage. This paper presents the analytical models to predict the reverse arch action (RAA) and the compressive arch action (CAA) of unbonded prestressed reinforced concrete (UPRC) beam-column sub-assemblages under column removal scenarios. In the models, the realistic stress–strain model for concrete is applied to calculate the compression force sustained by concrete, instead of the equivalent rectangular concrete stress block. A linear variation of the strains for concrete and steel reinforcement along the beam length is assumed. Moreover, a notional eccentricity of eccentric force imposing on beam section is introduced in the RAA model to determine its bending moment. Comparisons between FEM's and analytical results indicate that reasonable accuracy can be obtained in predicting not only the inverted camber and the RAA capacity of the sub-assemblages by the RAA model, but also the CAA capacity and the horizontal reaction force through the CAA model. Furthermore, the effects of effective prestress on the CAA of the sub-assemblages are investigated. Finally, through a contrastive analysis, it can be concluded that the increase of effective prestress is beneficial to the enhancement of CAA capacity to mitigate structural progressive collapse but worse to the ductility of beam section. [ABSTRACT FROM AUTHOR]

In this article, we investigate the set-membership state estimation problem for a class of time-varying systems with non-Gaussian noises over a FlexRay network. To mitigate the communication load and improve the flexibility of the data scheduling, the FlexRay protocol (FRP) governed by both the time-triggered and event-triggered rules is exploited to regulate the signal transmission in a cyclic fashion. A new expression of the input signal to the state estimator is formulated with intention to account for the effect of the FRP. Accordingly, a multirate model (orchestrating the sampling/updating rates of the target plant, sensors, and state estimator) is proposed and then transformed into a single-rate one with the help of the lifting technique and the vector augmentation method. Subsequently, sufficient conditions are provided for the true states to always reside in an ellipsoid at each time instant in the presence of the non-Gaussian noises, and such an ellipsoid is then minimized in the matrix-trace sense. An online optimization algorithm is developed to parameterize the estimator gains by means of the solution to certain recursive matrix inequalities. Numerical results demonstrate the validity of the proposed protocol-based set-membership state estimator design scheme. [ABSTRACT FROM AUTHOR]

In this article, the estimation problem of the state of charge (SOC) of Lithium-ion batteries is investigated. In order to truly reflect the unreliability of the sensor measured data, the data missing phenomenon with respect to the sensor measurement (e.g., the terminal voltage) is taken into account for the addressed estimation issue. By introducing a stochastic variable obeying the Bernoulli distribution with a known probability, the random occurrence of the sensor measurement unavailability is well characterized. The second-order resistor–capacitor equivalent circuit model, where the model parameters are identified by the recursive least-squares method, is developed to govern the dynamical behaviors of a Lithium-ion battery. A data-unavailability-resistant nonlinear recursive filtering algorithm is proposed to estimate the real SOC in an unreliable industrial environment. An upper bound of the filtering error covariance is obtained, which is further minimized at each sampling instant. In addition, the filter gain is recursively parameterized by solving an optimization problem with respect to two coupled recursive Riccati-like equations, thereby being suitable for the online implementation. Finally, extensive experiments are conducted to demonstrate the validity of the proposed filtering approach. [ABSTRACT FROM AUTHOR]

Coal will continue to be the main energy source in China for the immediate future, although the environmental pollution and ecological impacts of each stage in the full life cycle of coal mining, transportation, and combustion generate large quantities of external costs. The Late Permian coals in southwestern (SW) China usually contain high amounts of fluorine (F), arsenic (As), and ash, which together with high-F clays cause abnormally high levels of endemic fluorosis, As poisoning, and lung cancer in areas where coal is mined and burned. In this paper, we estimate the external costs of the life cycle of coal. The results show that the externalities of coal in SW China are estimated at USD 73.5 billion or 284.3 USD/t, which would have accounted for 6.5 % of the provincial GDP in this area in 2018. The external cost of human health accounts for 87.2% of the total external costs, of which endemic skeletal fluorosis diseases and related lung cancers have the most important impact. Our study provides a more precise estimate of externalities compared with its counterparts in other provinces in China. Therefore, several policy recommendations would be proposed to internalize the external cost. [ABSTRACT FROM AUTHOR]

Dual receiver encryption (DRE), being originally conceived at CCS 2004 as a proof technique, enables a ciphertext to be decrypted to the same plaintext by two different but dual receivers and becomes popular recently due to itself useful application potentials such secure outsourcing, trusted third party supervising, client puzzling, etc. Identity-based DRE (IB-DRE) further combines the bilateral advantages/facilities of DRE and identity-based encryption (IBE). Most previous constructions of IB-DRE are based on bilinear pairings, and thus suffers from known quantum algorithmic attacks. It is interesting to build IB-DRE schemes based on the well-known post quantum platforms, such as lattices. At ACISP 2018, Zhang et al. gave the first lattice-based construction of IB-DRE, and the main part of the public parameter in this scheme consists of 2 n + 2 matrices where n is the bit-length of arbitrary identity. In this paper, by introducing an injective map and a homomorphic computation technique due to Yamada at EUROCRYPT 2016, we propose another lattice-based construction of IB-DRE in an even efficient manner: The main part of the public parameters consists only of 2 p n 1 p + 2 matrices of the same dimensions, where p (≥ 2) is a flexible constant. The larger the p and n, the more observable of our proposal. Typically, when p = 2 and n = 284 according to the suggestion given by Peikert et al., the size of public parameters in our proposal is reduced to merely 12% of Zhang et al.'s method. In addition, to lighten the pressure of key generation center, we extend our lattice-based IB-DRE scheme to hierarchical scenario. Finally, both the IB-DRE scheme and the HIB-DRE scheme are proved to be indistinguishable against adaptively chosen identity and plaintext attacks (IND-ID-CPA). [ABSTRACT FROM AUTHOR]

• The proposed method can solve voltage issues and enable higher PV penetration. • PV imbalance makes traditional methods less effective on overvoltage mitigation. • A joint centralized-decentralized method is developed for unbalanced PV scenarios. • The new approach controls fast PV fluctuations in a coordinated and distributed way. Due to random connection of small-size single-phase rooftop photovoltaic (PV) generators in residential areas, low voltage distribution systems tend to have unbalanced PV integration across phases. In such situations, traditional reactive power compensation methods may cause unintended Voltage-Reactive Power responses across phases due to line coupling, which consequently affects their effectiveness on overvoltage mitigation. Such overvoltage problems significantly hinder the future integration of clean and renewable solar energy resources in power networks. In this paper, the limitations of traditional methods in PV imbalance scenarios are revealed and comprehensively analyzed by a voltage sensitivity method for the first time. On this basis, an innovative joint centralized-decentralized method is developed to overcome the PV imbalance-induced voltage regulation challenge. Specifically, the inverter's reactive power response to PV power variations in different phases is adaptively scheduled in order to avoid adverse effect of inter-phase Voltage-Reactive Power interaction on voltage regulation. The effectiveness of the proposed method is validated by time-series simulations with recorded data and a real-life low voltage distribution system in Australia. With the traditional method (i.e. power factor droop control strategy), 93 minutes' overvoltage can be observed in the case study, which will trigger overvoltage protection and disconnect PV inverters from the grid. While, the proposed method can always control the system voltage within the allowable range, and it consequently avoids PV disconnection. By solving this bottleneck issue, more PV systems can be integrated into distribution networks, which consequently contributes to CO 2 emission reduction in future. [ABSTRACT FROM AUTHOR]

Stripe (yellow) rust is one of the most destructive diseases in wheat production. More than 80 stripe rust resistance (Yr) genes have been officially named, however Yr26 gene has lost resistance to CYR34 (V26) since 2011. In this study, we evaluated resistance of 692 elite wheat cultivars from China to stripe rust in adult plant stage and resistance to CYR32, CYR33, and CYR34 Pst races in seedling stags. Yr26 was deduced in 692 cultivars by WE173 and WE33 molecular marks. The result showed that 45 (7%) entries had all-stage resistance, 79 (11%) entries had adult-plant resistance, and 568 (82%) entries were susceptible to one or more stripe rust races. Besides, 48 (81%) entries in over-summering region were resistant to CYR34, 4 (10%) in over-wintering region, 121 (20%) in spring epidemic region. And 43 entries across China were detected to have Yr26 gene. [ABSTRACT FROM AUTHOR]

Blockchain-enabled Internet of Things (IoT) systems have received extensive attention from academia and industry. Most previous constructions face the risk of leaking sensitive information since the servers can obtain plaintext data from the devices. To address this issue, in this paper, we propose a decentralized outsourcing computation (DOC) scheme, where the servers can perform fully homomorphic computations on encrypted data from the data owner according to the request of the data owner. In this process, the servers cannot obtain any plaintext data, and dishonest servers can be detected by the data owner. Then, we apply the DOC scheme in the IoT scenario to achieve a confidential blockchain-enabled IoT system, called BeeKeeper 2.0. To the best of our knowledge, this is the first work in which servers of a blockchain-enabled IoT system can perform any-degree homomorphic multiplications and any number of additions on encrypted data from devices according to the requests of the devices without obtaining any plaintext data of the devices. Finally, we provide a detailed performance evaluation for the BeeKeeper 2.0 system by deploying it on Hyperledger Fabric and using Hyperledger Caliper for performance testing. According to our tests, the time consumed between the request stage and recover stage is no more than 3.3 s, which theoretically satisfies the production needs. [ABSTRACT FROM AUTHOR]

Bromine contents of a 17-cm halite core from drilling hole of K203 in the Khorat Basin were analysed at 1 cm intervals (17 samples in total). The Br contents range from 99 to 184 ppm with a rapid variation. The K/Mg ratios of halite samples are tens of times higher than those of primary halite fluid inclusions. There is no positive correlation between Mg and Br contents, suggesting that fluid inclusions impose very little or negligible influence on Br contents of halites. The Br contents are not controlled by potash minerals either because the SEM examination shows no potash minerals and there is no relationship between K and Br contents. The Br contents of halite are thus primarily controlled by the Br concentrations of parent brines. The rapid variation of Br contents of halite within this section suggests a shallow saline pan wherein the giant Khorat evaporites were formed. This is contradictory to previous Br profiles of the Lower Salt Member which showed relatively stable and continuously increasing trends. The shallow saline pan model evidenced by high-resolution Br profile is consistent with sedimentary facies and salt mineral textures. [ABSTRACT FROM AUTHOR]

Many soil and water conservation measures (SWCM) have been implemented in the Loess Plateau of China, and they have an impact on ecosystems all levels and involve complicated mechanisms. Previously, studies typically focused on a single factor's effect on diversity or productivity. With this background, the current investigation embarked on an extensive study, with vegetation survey conducted in the no measure plots (NM), vegetation measure plots (VM) and engineering measure plots (EM) in the Loess Plateau of China. We used structural equation models (SEM) to explain the mechanism by which SWCM affects plant productivity and diversity. VM have direct effects on plant diversity, and EM have direct effects on soil properties and community structure. The two measures also had indirect effects on plant functional traits and community structure. The results show that the changes in plant functional traits and community structure by SWCM decreased plant diversity, whereas the increase of productivity was primarily dominated by improvements in community structure, and we conclude that variability in plant diversity and productivity across different measures on the Loess Plateau was primarily due to the responses of different plants to variable soil properties and the community responses. It was also emphasized that vegetation measures were beneficial to the increase of biomass per plant, while engineering measures were more beneficial to the growth of dominant species. These findings provide a theoretical foundation for vegetation management and restoration after the application of different SWCM. [Display omitted] • SWCM has a direct effect on plant productivity. • SWCM indirectly affect functional traits and community structure. • All SWCM have reduced plant diversity and increased productivity. • Vegetation Measures were beneficial to the increase of biomass per plant. • Engineering Measures were more suitable for the growth of dominant species. [ABSTRACT FROM AUTHOR]

Based on the NTRU trapdoor used in NIST's Falcon, a signcryption scheme following the sign-then-encrypt paradigm is constructed. The existing partitioning technique based on Waters hash over the lattice can not complete the security reduction in the standard model for the signature part due to the "partiality" of the pre-image generated with the NTRU trapdoor. To address this, a variant of Waters hash over small integers is proposed and, the probability of the successful reduction is analyzed. The resulting signcryption achieves existential unforgeability under the adaptive chosen-message attacks. By utilizing the uniqueness of the secret and the noise in an NTRU instance, the tag used in encryption is eliminated. Furthermore, a method to construct tamper-sensitive lattice public key encryption is proposed. This approach implants the ciphertext-sensitive information into the lattice public key encryption and binds it to the encrypted information. The malleability to the public key ciphertext triggers the change of the message–signature pair so that the IND-CCA2 security of the entire ciphertext can be guaranteed by the signature for the message. Thanks to the rational design and the efficiency of the NTRU trapdoor, the computational overhead of the proposed scheme is reduced significantly compared to the existing lattice-based signcryption scheme, reaching orders of magnitude improvement in efficiency. The experiment shows that the proposed scheme is efficient. [ABSTRACT FROM AUTHOR]

This paper is concerned with the pinning synchronization control issue for a class of discrete-time complex dynamical networks. By resorting to the interval observer approach, a novel pinning synchronization control strategy is adopted to control a small fraction of the network nodes with hope to reduce the implementation cost. By using the Lyapunov stability theorem, some synchronization criteria have been derived to ensure the desired synchronization performance. Finally, a numerical simulation is presented to illustrate the effectiveness and usefulness of the theoretical results. [ABSTRACT FROM AUTHOR]

In this paper, the stability of two weakly coupled elastic beams connected vertically by a spring is investigated via the frequency domain method and the multiplier technique. When the two beams have partially local damping, the operator A is obtained via variable conversion, and it generating a semigroup is proved, then we obtain that the semigroup is exponentially stable by reduction to absurdity. [ABSTRACT FROM AUTHOR]

Extreme rainfall may induce flooding failures of electricity facilities, which poses power systems in a risk of power supply interruption. To quantitatively estimate the risk of power system operation under extreme rainfall, a multi-scenario stochastic risk assessment method was proposed. First, a scenario generation scheme considering waterlogged faults of power facilities was constructed based on the storm water management model (SWMM) and the extreme learning machine method. These scenarios were merged with several typical scenario sets for further processing. The outage of power facilities will induce power flow transfer which may consequently lead to transmission lines' thermal limit violation. Semi-invariant and Gram–Charlier level expansion methods were adopted to analytically depict the probability density function and cumulative probability function of each line's power flow. The optimal solution was performed by a particle swarm algorithm to obtain proper load curtailment at each bus, and consequently, the violation probability of line thermal violations can be controlled within an allowable range. The volume of load curtailment as well as their importance were considered to quantitatively assess the risk of power supply security under extreme precipitation scenarios. The effectiveness of the proposed method was verified in case studies based on the Southeast Australia Power System. Simulation results indicated that the risk of load shedding in extreme precipitation scenarios can be quantitatively estimated, and the overload probability of lines can be controlled within the allowable range through the proposed optimal load shedding scheme. [ABSTRACT FROM AUTHOR]

With the increasing application of lithium-ion batteries, accurate estimation of the state of health (SOH) of lithium-ion batteries is of great significance for the safe operation of lithium-ion battery systems and the reduction of operation and maintenance costs. The complex physical and chemical reactions inside the lithium battery and the complex external working conditions make it challenging to achieve an accurate health-state estimation and life prediction. Therefore, the accurate estimation of the SOH of lithium-ion batteries is an important issue. At present, electrochemical impedance spectroscopy (EIS) is widely used in the study of battery-power impedance characteristics and battery-state estimation due to its advantage of nondestructive measurement. For this reason, this paper summarizes the research progress of lithium-ion SOH estimation based on EIS in recent years and details it layer by layer, mainly from two aspects: first, the quantitative relationship model between the characteristic parameters and SOH is established by constructing a frequency domain-equivalent circuit model. Secondly, we construct a quantitative relationship model between EIS data and SOH using the data-driven method. Finally, the advantages and disadvantages of different methods and estimation accuracy are analyzed and compared, and the future estimation of SOH based on EIS is prospected. [ABSTRACT FROM AUTHOR]

The concept of public key encryption with equality test was introduced at CT-RSA 2010. It has been used in many fields, especially in cloud storage. However, the previous schemes do not provide an effective authorization mechanism. To fill this gap, Ma et al. presented a public key encryption with equality test supporting flexible authorization based on the bilinear pairings. Recently, Lin et al. presented a pairing-free scheme that employs quadratic curve to perform the equality tests, which can achieve a trade-off between computational cost and storage space. In this article, we show that the equality test can be better performed by using a straight line, rather than a quadratic curve. Moreover, we simplify the encryption algorithm, as well as reduce the ciphertext storage space. [ABSTRACT FROM AUTHOR]