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In response to growing concerns about public safety and environmental conservation, it is essential to develop a precise identification method for trace explosives. To improve the stability and detection sensitivity of perovskite quantum dots (PQDs) and address the issue of low porosity in traditional polymer-based photonic crystals (PhCs), this study proposed a PQD photoluminescence (PL) enhancement strategy based on the slow light effect of ZIF-8 PhCs for highly sensitive, selective, and convenient detection of 2,4,6-trinitrophenol (TNP). The slow light effect at the photonic band gap edge is the basis of amplifying the PL signal. PhCs were fabricated by the evaporation-induced self-assembly method. The diffraction wavelength overlapping the whole visible region was designed to match the emission wavelength of PQDs. Results showed that PhCs matching the PBG edge with PQDs’ emission peak amplified the PL signal 11.3 times, significantly improving sensitivity for trace TNP detection with a limit as low as 2.52 nM. Moreover, there was a 13.3-fold enhancement of PQDs’ fluorescence lifetime when the emission wavelength fell in the PBG range. The hydrophobic surface of ZIF-8 PhCs enhanced the PQDs’ stability and moisture resistance. Furthermore, the selective quenching mechanism of TNP by the sensor was photoinduced electron transfer (PET) verified by DFT calculations and time-resolved PL decay dynamics measurements. This study demonstrated great potential for manipulating light emission enhancement by PhCs in developing efficient fluorescent sensors for trace environmental pollutant detection.

Quantum Mechanics/Molecular Mechanics (QM/MM) can describe chemical reactions in molecular dynamics (MD) simulations at a much lower cost than ab initioMD. Still, it is prohibitively expensive for many systems of interest because such systems usually require long simulations for sufficient statistical sampling. Additional MM degrees of freedom are often slow and numerous but secondary in interest. Coarse-graining (CG) is well-known to be able to speed up sampling through both reduction in simulation cost and the ability to accelerate the dynamics. Therefore, embedding a QM system in a CG environment can be a promising way of expediting sampling without compromising the information about the QM subsystem. Sinitskiy and Voth first proposed the theory of Quantum Mechanics/Coarse-grained Molecular Mechanics (QM/CG-MM) with a bottom-up CG mapping. Mironenko and Voth subsequently introduced the DFT-QM/CG-MM formalism to couple a Density Functional Theory (DFT) treated QM system and to an apolar environment. Here, we present a more complete theory that addresses MM environments with significant polarity by explicitly accounting for the electrostatic coupling. We demonstrate our QM/CG-MM method with a chloride-methyl chloride SN2 reaction system in acetone, which is sensitive to solvent polarity. The method accurately recapitulates the potential of mean force for the substitution reaction, and the reaction barrier from the best model agrees with the atomistic simulations within sampling error. These models also have generalizability. In two other reactive systems that they have not been trained on, the QM/CG-MM model still achieves the same level of agreement with the atomistic QM/MM models. Finally, we show that in these examples the speed-up in the sampling is proportional to the acceleration of the rotational dynamics of the solvent in the CG system.

Ultrasound, as an efficient, clean, and safe processing technology, is widely used in industries. Grain refiners are widely used in the refinement of cast alloys. In this study, ultrasonic technology (UT) and Al–5Ti–1B refiner prepared by continuous rheological extrusion (CRE Al–5Ti–1B) were used to modify the recycled Al–Mg–Si-based alloy, and the microstructure and mechanical properties of the recycled Al–Mg–Si-based alloy were studied. The differences in porosity and grain refinement caused by ultrasonic power were discussed. Results showed that, increasing the ultrasonic power can effectively reduce the porosity of the recycled Al–Mg–Si-based alloy. The synergistic effect of UT and CRE Al–5Ti–1B refiner significantly refined α-Al grains and second phases. The increase of ultrasonic power can effectively cause deagglomeration while reducing the nucleation undercooling of α-Al, which promotes the refinement of the recycled Al–Mg–Si-based alloy and significantly improves the mechanical properties. The yield strength (YS), ultimate tensile strength (UTS) and elongation (EL) of the recycled Al–Mg–Si-based alloy were 106 MPa, 210 MPa and 9.4%, respectively. When 0.2 wt% CRE Al–5Ti–1B refiner was added and the ultrasonic power was 150 W, the YS, UTS, and EL were improved by 12.8%, 28.8% and 228.4%, respectively.

Simulating chemically reactive phenomena such as proton transport on nanosecond to microsecond and beyond time scales is a challenging task. Ab initiomethods are unable to currently access these time scales routinely, and traditional molecular dynamics methods feature fixed bonding arrangements that cannot account for changes in the system’s bonding topology. The Multiscale Reactive Molecular Dynamics (MS-RMD) method, as implemented in the Rapid Approach for Proton Transport and Other Reactions (RAPTOR) software package for the LAMMPS molecular dynamics code, offers a method to routinely sample longer time scale reactive simulation data with statistical precision. RAPTOR may also be interfaced with enhanced sampling methods to drive simulations toward the analysis of reactive rare events, and a number of collective variables (CVs) have been developed to facilitate this. Key advances to this methodology, including GPU acceleration efforts and novel CVs to model water wire formation are reviewed, along with recent applications of the method which demonstrate its versatility and robustness.

Towards realizing the future quantum internet1,2, a pivotal milestone entails the transition from two-node proof-of-principle experiments conducted in laboratories to comprehensive multi-node set-ups on large scales. Here we report the creation of memory–memory entanglement in a multi-node quantum network over a metropolitan area. We use three independent memory nodes, each of which is equipped with an atomic ensemble quantum memory3that has telecom conversion, together with a photonic server where detection of a single photon heralds the success of entanglement generation. The memory nodes are maximally separated apart for 12.5 kilometres. We actively stabilize the phase variance owing to fibre links and control lasers. We demonstrate concurrent entanglement generation between any two memory nodes. The memory lifetime is longer than the round-trip communication time. Our work provides a metropolitan-scale testbed for the evaluation and exploration of multi-node quantum network protocols and starts a stage of quantum internet research.

The gut microbiota are known to play an important role in host health and disease. Alterations in the gut microbiota composition can disrupt the stability of the gut ecosystem, which may result in noncommunicable chronic diseases (NCCDs). Remodeling the gut microbiota through personalized nutrition is a novel therapeutic avenue for both disease control and prevention. However, whether there are commonly used gut microbiota-targeted diets and how gut microbiota–diet interactions combat NCCDs and improve health remain questions to be addressed. Lactoferrin (LF), which is broadly used in dietary supplements, acts not only as an antimicrobial in the defense against enteropathogenic bacteria but also as a prebiotic to propagate certain probiotics. Thus, LF-induced gut microbiota alterations can be harnessed to induce changes in host physiology, and the underpinnings of their relationships and mechanisms are beginning to unravel in studies involving humans and animal models.

For enhancing the efficiency and accuracy of structural reliability estimation, a support vector machine-based pre-calculation error (PESVM) is proposed by integrating support vector machine (SVM), constraints conversion, and pre-calculation error (PE). Based on SVM modeling theory, the constraints conversion is applied to transform the original inequality constraints into equality constraints, contributing to the simplification of solving Lagrange multipliers and the improvement of computational efficiency. To eliminate the effects of abnormal values, PE is introduced to act as slack variables that adaptively prescribe the degree of model margin violation, which is workable to improve the calculation precision. Two study cases containing nose landing gear shock strut outer cylinder stress and turbine blisk radial deformation are applied to train the PESVM models and verify their performances compared with other reliability analysis methods. The results show that (i) the PESVM holds highest modeling efficiency and precision among the three methods; (ii) the PESVM shows superior performance than Kriging and SVM in simulation speed and accuracy; (iii) the reliability degrees of two study cases are 0.9973 (shock strut outer cylinder stress) and 0.9975 (turbine blisk radial deformation) when the allowable values 1.4968 × 109Pa and 1.8892 × 10–3m subject to 3σprinciple; (iv) the PESVM takes on preferably strong robustness in modeling and simulation. The PESVM method is validated to be applicable and efficient for structural reliability analysis. The contribution of this paper is helpful for providing a promising inspiration for structural reliability evaluation.

In recent decades, grain refiners had not only improved the properties on cast aluminum alloy, but also changed the application field of cast aluminum alloys, which had attracted widespread attention. However, there were few reports on microstructure evolution of A356/CRE Al-X-Ce(Ti, C) system by combining traditional grain refiners with element Ce. In this study, refined A356 alloys with excellent strength and plasticity were obtained by adding CRE Al-X-Ce(Ti, C) (0, 0.4, 0.8, 1.2, 1.6 and 2.0 wt%, respectively). Using XRD, SEM and TEM, the morphology of phases in the refined A356 alloy and phases of grain refiner were identified. The microstructure evolution of α-Al grains and eutectic Si with the introduction of TiC and Ce was analyzed. The results showed that the novel CRE Al-X-Ce(Ti, C) could not only effectively refine α-Al grains, but also modify Si microstructure of the alloy. The refined A356 alloys with excellent strength and plasticity were obtained with 2.0 and 1.6 wt% grain refiner (CRE) additions, respectively. TiC as nucleation particle and Ce as the surfactant refined the α-Al grains. Also, Ce modified eutectic Si by changing the way it grows. When the CRE Al-X-Ce(Ti, C) content researched 2.0 wt%, the long plate-like Al–Si–Ce phase was formed which can easily caused cracks and reduced the elongation of alloy.

A356 alloy is a commonly used casting Al-Si alloy. Because of the excellent fluidity, air-tightness and thermal resistance, it is usually used as castings with complex structure. However, due to the coarse α-Al grains and needle-like phases, the defects including shrinkage cavity and porosity can easily be formed, which reduce the mechanical properties of the castings and lead to the lower safety factor. In this paper, Al-5Ti-0.6C-xCe (x = 0, 0.5, 1.0, 1.5 and 2.0 wt%) master alloys have been prepared by fluorine-salt method combined with the continuous rheological extrusion (CRE) technology. The response of mechanical properties of A356 alloy to the CRE Al-Ti-C-Ce alloys addition upon different Ce contents was investigated. Results showed that, with the increasing Ce content from 0 to 2.0 wt%, the average grain size of α-Al and length of coarse needle-like phases in A356 alloy changed nonmonotonically. When the Ce content was 1.0 wt%, the best refined structure was obtained. The tensile strength, yield strength and elongation of refined A356 by CRE Al-5Ti-0.6C-1.0Ce master alloy were 290.45 MPa, 238.27 MPa and 2.80%, respectively. The introduction of master alloys with different Ce contents promoted the refinement of grain and coarse needle-like phase in A356 alloy, which further improved the mechanical property of the alloy.

Local microstructure and strengthening mechanisms of double-sided friction stir welded Al-Mg-Mn-Er alloy joint were investigated to reveal its softening mechanism. The results showed that a fine equiaxed grain structure (5.61 μm) was formed in the nugget zone (NZ), while the thermo-mechanically affected zone (TMAZ, 45.32 μm) and heat-affected zone (HAZ, 100.73 μm) maintained a fibrous grain structure. The fraction of low angle grain boundaries decreased from 75.6% of the base metal (BM) to 15.6% of the NZ. The annealing effect resulted in obvious reduction in dislocation density from 1.8×1014m−2of the BM to 4.5×1012m−2of the NZ. The average diameter size and volume fraction of Al3(Er, Zr) precipitates of the NZ, TMAZ and HAZ were close to those of the BM (13.7 nm and 0.13%). The NZ and TMAZ exhibited the lowest yield strength of about 201 MPa while the BM had the highest yield strength of about 295 MPa. The loss of the dislocation strengthening and substructure strengthening was the main reason for the decrease of yield strength from the BM to the NZ.

A series of di- and tetranuclear lanthanide complexes with the formulas [Dy2bmzch(tmhd)5(CH3OH)]·CH3OH (1), [Dy2bmzch(dbm)4(CH3O)(CH3OH)]·0.5CH3OH·0.5H2O (2), and Dy4bmzch(btfa)10(3), where tmhd = 2,2,6,6-tetramethyl-3,5-heptanedionate, dbm = dibenzoylmethane, btfa = benzoyltrifluoroacetone, and bmzch = (Z)-N-[(E)-pyrimidin-2-ylmethylene]pyrimidine-2-carbohydrazonate, were structurally and magnetically characterized. More strikingly, although the nitrogen-enriched bridged ligand 3,6-di(pyrimidin-2-yl)-1,2,4,5-tetrazine (bmtz) was initially adopted, the structures of the complexes obtained indicated that bmtz underwent unprecedented asymmetric ring opening and generated a new ligand bmzch. Combined with different β-diketonates, di- and tetranuclear dysprosium complexes were constructed in which the structural patterns are very sensitive to the selected β-diketonates. In view of this, the bilateral and unilateral dinuclear Dy2 complexes 1and 2and tetranuclear Dy4 complex 3were obtained by choosing different β-diketonates. Magnetic test results reveal that both complexes 1and 3showcase typical slow magnetic relaxation behavior without an external direct-current field and the effective energy barrier of the latter is almost twice that of the former, while complex 2only displays in-field single-molecule-magnetic behavior. Also of note is that these are the first tetrazine-type dysprosium-based single-molecule-magnets undergoing in situ asymmetric ring-opening reaction of this ligand that are formed.

Purpose: The purpose of this paper is to briefly summarize and review the theories and methods of complex structures’ dynamic reliability. Complex structures are usually assembled from multiple components and subjected to time-varying loads of aerodynamic, structural, thermal and other physical fields; its reliability analysis is of great significance to ensure the safe operation of large-scale equipment such as aviation and machinery. Design/methodology/approach: In this paper for the single-objective dynamic reliability analysis of complex structures, the calculation can be categorized into Monte Carlo (MC), outcrossing rate, envelope functions and extreme value methods. The series-parallel and expansion methods, multi-extremum surrogate models and decomposed-coordinated surrogate models are summarized for the multiobjective dynamic reliability analysis of complex structures. Findings: The numerical complex compound function and turbine blisk are used as examples to illustrate the performance of single-objective and multiobjective dynamic reliability analysis methods. Then the future development direction of dynamic reliability analysis of complex structures is prospected. Originality/value: The paper provides a useful reference for further theoretical research and engineering application.

Traumatic brain injury (TBI) is characterized by neuronal loss and subsequent brain damage and can be accompanied by transient or permanent neurological dysfunction. The recovery of cognitive function after TBI is a challenge. This study aimed at investigating whether treatment with resveratrol (RSV) could prevent cognitive dysfunction after TBI in mice. TBI mouse model using weight drop-impact method. Male mice aged from 7 to 9 weeks were randomly divided into four groups: TBI group, TBI + vehicle group, TBI + RSV group, and sham-operated control group. The animals from the TBI + vehicle group and TBI + RSV group were intraperitoneally injected at 3 and 24 h post-TBI with placebo and RSV (3%, 5 ml/kg), respectively. Two days after TBI, the hippocampus of mice was extracted, and western blot analysis was performed for Sirtuin 1 (SIRT1), synaptophysin (SYP), p38 mitogen-activated protein kinase (MAPK), and P-p38 MAPK. Moreover, behavioral functions of TBI mice were evaluated by Y maze to determine RSV efficacy in preventing cognitive impairment in TBI. RSV increased the expression of SIRT1 protein, which in turn activated the phosphorylation of p38 MAPK. Taken together, our findings suggest that RSV exerts a strong beneficial effect on improving neurological function induced by TBI.

Privacy protection is a hot topic in network security, many scholars are committed to evaluating privacy information disclosure by quantifying privacy, thereby protecting privacy and preventing telecommunications fraud. However, in the process of quantitative privacy, few people consider the reasoning relationship between privacy information, which leads to the underestimation of privacy disclosure and privacy disclosure caused by malicious reasoning. This paper completes an experiment on privacy information disclosure in the real world based on WordNet ontology .According to a privacy measurement algorithm, this experiment calculates the privacy disclosure of public figures in different fields, and conducts horizontal and vertical analysis to obtain different privacy disclosure characteristics. The experiment not only shows the situation of privacy disclosure, but also gives suggestions and method to reduce privacy disclosure.

There are currently many types of access control models and schemes that have been proposed to protect valuable resources in a distributed environment. Many such models have failed to take into consideration efficiency, security, practical implementation and management at the same time. Based on the analysis of conventional certificate-based access control characteristics, this paper proposes an authorisation certificate-based access control (ACBAC) model to realise access control in a distributed environment. Employing certificates in access control can help meet the various requirements in distributed networks or systems while ensuring security to a great extent. Efficiency and security can thus be improved by delegating the functions of making access authorisation decisions to the certificate issuer (CI). We will formally describe the model, introduce the application scenarios and the processes of the model, and provide the details of implementation. Finally, the effectiveness and superiority of the model is verified through experiment and analysis.

Multilayer graphene oxide (GO) is introduced to prepare P84/GO hybrid membrane to enhance the permselectivity of polyimide membrane while triethylenetetramine is used to improve the solvent resistance of the membrane. Effect of GO content on performance and morphology of P84/GO mixed matrix membrane is researched in detail. The membrane shows high rejection (100%) to gentian violet (408 Da) and high flux (118 L m–2h–1) at 0.1 MPa and ambient temperature when the casting solution contains 18% P84 and 2% GO. The membrane shows excellent solvent resistance in dimethylformamide, acetone and methanol when it is immersed in the pure solvent for 18 d.

Thiamin and its phosphate derivatives are ubiquitous molecules involved as essential cofactors in many cellular processes. The de novobiosynthesis of thiamin employs the parallel synthesis of 4-methyl-5-(2-hydroxyethyl)thiazole (THZ-P) and 4-amino-2-methyl-5(diphosphooxymethyl) pyrimidine (HMP) pyrophosphate (HMP-PP), which are coupled to generate thiamin phosphate. Most organisms that can biosynthesize thiamin employ a kinase (HMPK or ThiD) to generate HMP-PP. In nearly all cases, this enzyme is bifunctional and can also salvage free HMP, producing HMP-P, the monophosphate precursor of HMP-PP. Here we present high-resolution crystal structures of an HMPK from Acinetobacter baumannii(AbHMPK), both unliganded and with pyridoxal 5-phosphate (PLP) noncovalently bound. Despite the similarity between HMPK and pyridoxal kinase enzymes, our kinetics analysis indicates that AbHMPK accepts HMP exclusively as a substrate and cannot turn over pyridoxal, pyridoxamine, or pyridoxine nor does it display phosphatase activity. PLP does, however, act as a weak inhibitor of AbHMPK with an IC50of 768 μM. Surprisingly, unlike other HMPKs, AbHMPK catalyzes only the phosphorylation of HMP and does not generate the diphosphate HMP-PP. This suggests that an additional kinase is present in A. baumannii, or an alternative mechanism is in operation to complete the biosynthesis of thiamin.

To improve the computational efficiency and accuracy of multi-objective reliability estimation for aerospace engineering structural systems, the Intelligent Vectorial Surrogate Modeling (IVSM) concept is presented by fusing the compact support region, surrogate modeling methods, matrix theory, and Bayesian optimization strategy. In this concept, the compact support region is employed to select effective modeling samples; the surrogate modeling methods are employed to establish a functional relationship between input variables and output responses; the matrix theory is adopted to establish the vector and cell arrays of modeling parameters and synchronously determine multi-objective limit state functions; the Bayesian optimization strategy is utilized to search for the optimal hyperparameters for modeling. Under this concept, the Intelligent Vectorial Neural Network (IVNN) method is proposed based on deep neural network to realize the reliability analysis of multi-objective aerospace engineering structural systems synchronously. The multi-output response function approximation problem and two engineering application cases (i.e., landing gear brake system temperature and aeroengine turbine blisk multi-failures) are used to verify the applicability of IVNN method. The results indicate that the proposed approach holds advantages in modeling properties and simulation performances. The efforts of this paper can offer a valuable reference for the improvement of multi-objective reliability assessment theory.

Objective To investigate CUE domain containing 2 (CUEDC2) expression in colorectal cancer with different invasion and migration abilities.Methods Fresh colon cancer tissues, obtained from patients with or without lymph node metastasis who were treated at the Department of General Surgery, Chinese People's Liberation Army General Hospital, and SW620 and HT29 colorectal cancer cell lines, were analysed for CUEDC2expression.Results Real-time polymerase chain reaction showed significantly higher CUEDC2 mRNA levels in colon cancer tissue from patients with (n= 8) versus without (n= 8) lymph node metastasis, and in SW620 versus HT29 cells. Western blots revealed significantly higher CUEDC2 protein levels in colon cancer tissues from patients with versus without lymph node metastasis, and in SW620 versus HT29 cells. Colorectal cancer tissues from patients with lymph node metastasis showed more intense immunohistochemical staining and moderate staining of cell nuclei and cytoplasm versus less intense/weak staining in tissues from patients without lymph node metastasis.Conclusions CUEDC2is highly expressed in colorectal cancer tissues and colorectal cancer cell lines with high invasion and migration ability. CUEDC2 may be involved in promoting invasion and metastasis in colorectal cancer.

•Establishing a simulation of recovering water and waste heat system.•Analysis of the unit load, condensate flow rate and circulation water flow.•Recovery power and efficiency of waste heat and water are analyzed.•Recovered water can supplement up to 60% of the evaporation water.

The poor penetration ability of antimicrobial agents limits their use in the treatment of intracellular bacteria. In this study, the conjugate CNC (6) was generated by connecting the cell-penetrating peptide Tat11(1) and marine peptide N6 (2) via a cathepsin-cleavable linker, and the C-terminal aminated N6 (7) and CNC (8) were first designed and synthesized to eliminate intracellular SalmonellaeTyphimurium. The cellular uptake of 6and stability of 7were higher than those of 2, and conjugates 6, 8, and 7had almost no hemolysis and cytotoxicity. The antibacterial activities of 6, 8, and 7against S.Typhimurium in RAW264.7 cells were increased by 67.2–76.2%, 98.6–98.9%, and 96.3–97.6%, respectively. After treatment with 1–2 μmol/kg of 6, 8, or 7, the survival of the S.Typhimurium–infected mice was 66.7–100%, higher than that of 2(33.4–66.7%). This result suggested that 6, 8, and 7may be excellent candidates for novel antimicrobial agents to treat intracellular pathogens.

Inorganic nanosheets materials are attracting more and more attention to prepare mixed matrix membrane (MMM) with excellent performance. MXene, a new kind of 2D transition metal carbides material, has the similar lamellar structure as graphene oxide and it is a potential material of separation membrane. In this work, the typical MXene material named Ti3C2Txis used to prepare MXene/cellulose acetate (CA) MMM with phase inversion method. The scanning electronic microscopic images of the membrane show the dense functional layer without visible defects. The MXene/CA MMM prepared with 18% CA and 3% MXene shows high rejection to Gentian Violet (408 Da) 100% with flux of 4.2 L/m2h at 0.3 MPa. It also has high rejection to Na2SO489.6% with flux of 4.8 L/m2h at 0.3 MPa. After crosslinking with 5% glutaraldehyde at 60°C, the MMM performance does not decline after immersion in 50% dimethylacetamide solution for 12 d, which means excellent solvent resistance of the membrane. Compared with CA membrane, MXene/CA MMM also has better fouling resistance.

Background/aimsTo investigate the clinical features of Chinese patients with seropositive myelin oligodendrocyte glycoprotein antibody (MOG-Ab) optic neuritis (ON) and patients with seropositive aquaporin-4 antibody (AQP4-Ab) ON.MethodsIn this retrospective observational study, sera from patients with demyelinating ON were tested for MOG-Ab and AQP4-Ab with a cell-based assay. Clinical characteristics were compared between MOG-Ab-related ON (MOG-ON) and AQP4-Ab-related ON (AQP4-ON), including visual performances, serum autoantibodies and features on MRI.ResultsA total of 109 affected eyes from 65 patients with demyelinating ON (20 MOG-ON and 45 AQP4-ON) were included. The onset age of MOG-ON was younger than AQP4-ON (MOG-ON: 20.2±17.4 years old, AQP4-ON: 35.6±15.7 years old, P=0.001). Onset severity was not different between these two groups (P=0.112), but patients with MOG-ON showed better visual outcomes (P=0.004). Half of the MOG-ON had a relapsing disease course. Nineteen per cent of patients with AQP4-ON presented coexisting autoimmune disorders, but there were no coexisting autoimmune disorders among patients with MOG-ON. Optic nerve head swelling was more prevalent in patients with MOG-ON (P<0.01). Retrobulbar segment involvement of the optic nerve were more common in patients with MOG-ON according to our MRI findings (P<0.01). Patients with MOG-ON showed longitudinally extensive lesion in 30% and chiasm and optic tract involvement in 5%.ConclusionsMOG-ON is not rare in Chinese demyelinating patients. It underwent a severe vision loss at onset but had relatively better visual recovery than patients with AQP4-ON. MOG-ON might have an unique pathogenesis different from AQP4-ON.

Roundness is defined as the degree that the cross section of an object is close to a theoretical circle. In the cigarette production process, the quality and production efficiency of a cigarette are directly affected by the roundness of the un-cut cigarette. To improve the current measurement method using a charge-coupled device (CCD) sensor and measure the roundness of cigarettes in the production line, a visual detection system composed of an industrial camera and a structural light is developed. The system’s roundness-calculation method is closer to the real environment of the cigarette roundness. In this visual system, the line-structure light shines on the cigarette with a fixed angle and height in a longitudinal section, forming a crescent-shaped spot when the industrial camera cannot capture the cigarette’s end surface. Then, the spot is analyzed using image-processing techniques, such as a median filter and ellipse fitting, after the industrial camera captures the spot. The system with a non-contact measurement style can meet the requirements of on-line cigarette detection with stable results and high precision.

Although freeze-drying is a widely used dehydration technique for the stabilizing of unstable lactic acid bacteria, Lactobacillus paracaseisubsp. paracaseiJCM 8130T(L. paracasei) is destabilized after freeze-drying and subsequent storage. In order to improve the stability of freeze-dried L. paracasei, effects of disaccharides (sucrose and trehalose), polymers (maltodextrin; MD and bovine serum albumin; BSA), and their mixtures on the survival rate of freeze-dried L. paracaseiwere investigated. The survival rate of non-additive sample decreased slightly after freeze-drying but decreased drastically after subsequent storage at 37 °C for 4 weeks. The reduction was diminished by the addition of disaccharides and polymers. The stabilizing effect of disaccharides was not affected by the co-addition of MD. In contrast, the disaccharide–BSA mixtures had a synergistic stabilizing effect, and the survival rates were largely maintained even after storage. It is suggested that the synergistic effect originates from the conformational stabilization of the dehydrated bacteria.

Social ties, as informal institutions, contribute to firms’ performance in emerging economies. Formal market-supporting institutions in emerging economies are in general less developed, social ties cultivated by entrepreneurs thus serve as substitutes for formal institutional support. However, the role of social ties as informal institutions and interactions between social ties and market-supporting institutions are yet to be fully explored. Using the sample of 428 newly listed firms on the Growth Enterprise Market of Shenzhen Stock Exchange of China between 2009 and 2016, this paper examines the interplays among the entrepreneurial founder's political ties and managerial ties, marketization, and firm's productivity, measured by firm-level total factor productivity. Our findings indicate that the entrepreneurial founder's managerial ties enhance firm productivity whilst political ties reduce productivity. We also find that marketization positively moderates the effects of the entrepreneurial founder's political and managerial ties on productivity. Our findings demonstrate the strategic importance of the informal institutions and contribute to an improved understanding of the complementary effects between social ties and marketization in an important emerging economy.

To explore the effect of moxibustion for preventing post-hemorrhoidectomy urinary retention of mixed hemorrhoids.

The high temperature oxidation phenomenon will occur on the tool-workpiece contact area when machining the superalloy. Two kinds of cemented carbide tools (YG6X, YG8) are selected, the coated carbide tool and coated ceramic tool which are suitable for machining superalloy are selected. The resistance furnace is used for heating tool material, and the oxidation resistance experiments are carried out. The results show that: WC which is included in the cemented carbide tool is oxidized to WO3 and the Co is oxidized to Co3O4, Ti which is included in the coated carbide tool is oxidized to TiO2. The grain of the tool is smaller, the oxidation resistance is better. The oxidation resistant of coated carbide tool is better than the non-coated tools. The coated ceramic tool is not substantially oxidized in high temperature situation. The merits order of the oxidation resistant properties is that: coated ceramic tool>coated carbide tool > YG6X>YG8.

Cutting force, cutting heat and tool wear are closely related to the friction characteristics of tool-chip interface in the process of metal cutting. The variation of the cutting speed and temperature have been analyzed by the distribution of stress and strain in the primary and the secondary shear zone. A new friction model has been established to analyze the contact length between cutting tool and chip and local friction coefficient at the sliding zone. Cutting experiments have been performed in the process of carbide tools cutting the titaniumTi6Al4V, the contact length of sticking zone and sliding zone and friction coefficient have been analyzed by measured cutting force. The simulation of cutting process has been carried out based on Deform software, then the simulation results have been compared with the test ones, which verifies the accuracy of the established model.

A hospital-based cross-sectional study was performed, including 117 psoriatic patients and 117 controls matched for age, gender, and body mass index. Psoriatic patients had higher levels of serum uric acid (6.25 ± 1.62 vs 5.71 ± 1.35 mg/dl; P=0.019) and significantly greater prevalence of hyperuricemia (31.6% vs 16.2%; P=0.009) than individuals without psoriasis. Psoriatic patients had significantly higher serum uric acid than controls in subjects without metabolic syndrome. Multivariate logistic regression analysis showed that psoriasis can be a strong predictor of hyperuricemia (odds ratio 2.61; 95% confidence interval 1.34-5.00; P=0.004).

•Building an experimental platform for flue gas dehydration with the ceramic membrane tube.•Circulating water and purge gas are used as the cooling medium.•The operating parameters are divided into flue gas and cooling medium parameters.•Correlation analysis of permeate flux and intrinsic factors influenced by operating parameters.•Excessive transmembrane pressure difference can damage the selective permeability of ceramic membranes.

In this paper a 6-DOF(Degree of Freedom) vibration isolation platform with structural configuration of 3CPS (3 Cylindrical-Prismatic-Spherical)-1UPS (1 Universal-Prismatic-Spherical) parallel mechanism is proposed. Firstly, the dynamic model is developed through virtual work principle. The transfer function and the complex frequency response function were obtained from the dynamical equation. Then, 36 amplitude frequency diagrams are obtained from the frequency response function. By analyzing the 36 amplitude frequency diagrams, 10 vibration coupling terms were chosen. The range of the spring stiffness coefficient and the range of the damping coefficient of the magneto-rheological damper are determined by analyzing the acceleration transmissibility of the 10 vibration coupling terms. At last, an integrated optimization combining structural and controller optimization is developed. The optimal parameters of the parallel mechanism are obtained through Genetic Algorithm (GA). This work is significant for the prototype design and verification of the vibration isolator.

In titanium alloy machining, under different cooling lubrication conditions, the variation of tool wear and chip morphology have a certain effect on the surface roughness. Under different cooling lubrication conditions, in order to analyze the variation of tool wear, chip morphology and surface roughness, the surface roughness values are measured ​​and the variation in tool wear and chip morphology are observed, and then the interaction relationship between the tool wear and the chip morphology is analyzed. The results show that the tool wear and chip morphology influence on the surface roughness. Under different cooling lubrication, the rake face wear do not change significantly, but wet cooling and MQL play a protective role for the flank face wear.

The various feed rate and cutting speed have an important influence on cutting force, tool wear and chip morphology in machining titanium alloy. Cutting experiments are carried out analyzing the titanium alloy Ti6Al4V under different cutting speed and feed rate, the cutting force values are obtained. The analysis results show that the dominant wear pattern is adhesion wear and chipping. And the tool wear also has an influence on chip morphology.

The objective of this research is to construct an efficient way of monitoring water quality and assessing trophic state using remote sensing techniques in Qinshan Lake of Hangzhou, China. Two Landsat ETM+ images were acquired and simultaneous in situ measurements, sampling and analysis were conducted. Results of the study indicated that the ratio of ETM+1/ETM+3 was the most effective single band in estimating chlorophyll-a (Chl-a), followed by normalized ratio vegetation index (NRVI). Two multiple regression models with determination coefficients were further constructed between logarithmically transformed Chl-a and the combination of ETM+1/ETM+3, ETM+2/ETM+3, and ETM+3/ETM+4 of ten sample sites. The resulting models, Log (Chl-a)=1.65 + 0.87*(ETM+1 / ETM+3) 3.39*(ETM+2 / ETM+3) + 0.89*(ETM+3 / ETM+4), and Log (Chl-a)=2.94 1.37*(ETM+1 / ETM+3) + 0.40*(ETM+2 / ETM+3) 0.20*(ETM+3 / ETM+4), both showed strong ability to evaluate the distribution of Chl-a, with R2 of 0.72 and 0.92, respectively. Then two trophic state maps generated for Qinshan Lake using this model could identify zones with a higher potential for eutrophication, which turned out to be an appropriate method for synoptic monitoring of water quality in lakes. Similar modeling can be made for any given subtropical lake, to provide rapid and long term assessment of water quality and also useful information for decision making.

We present a tapered dual elliptical plasmon waveguide for terahertz waves. This element is composed of a pair of tapered elliptical metal structures and is especially suitable for the coupling of terahertz waves from an approximate plate waveguide to a two-wire waveguide. The long axes of the two ellipses gradually reduce to the same sizes as the short axes, and thus the two-ellipse structure is now a two-wire waveguide. The slowly tapered structure eliminates the reflection and scattering during the coupling process according to WKB approximation. The numerical result shows that the coupling efficiency of this connector can reach as high as 94%.

The existence of Neumann boundary is a major cause of the poor accuracy and instability of collocation-based methods. Taking a Poisson equation with Neumann boundary condition as the model, the present paper studies the effects of two different radial point interpolation shape functions and their parameters on the accuracy of numerical solutions of the equation. We also study the effects of methods including fictious point method, nodes densification method and Hermite collocation method on the improvement of numerical accuracy. By comparison of analytic and numerical solutions computed using a program developed during research, we obtain parameters of shape functions and methods of treatment of Neumann boundary conditions that can be adopted to give better numerical accuracy.

Manufacturing of complex products is a multi-resource coupling process, in order to achieve precise control of its manufacturing process, it should ensure that the manufacturing process information is get in real-time and accurately, achieving the real synchronization of logistics and information flow. Complex products manufacturing workshop represented with aerospace products have poor real-time production information, low production information integration and low visual production monitoring. In order to solve those problems, this paper constructs manufacturing process visualized real-time monitoring system, this system is able to reflect the real-time dynamic workshop production schedule information, quality testing information and abnormal production information and so on. Combined with assembly plant of an Aerospace institutes actual production, this paper designs the architecture, functional structure as well as its business processes of the system, and proposes a metadata-based multi-source heterogeneous information integration technology, then, processes and integrates the collected production process information effectively and displays it through the station terminal, workshops signage. The system is able to share the workshop information resources effectively, and it has been successfully applied to the assembly plant, and has achieved good effect.

The tuning of PID controller parameters is the most important task in PID design process. A new tuning method is presented for PID parameters, based on multi-objective optimization technique and multi-attribute decision making method. Three performances of a PID controller, i.e. the accurate set point tracking, disturbance attenuation and robust stability are studied simultaneously. These specifications are usually competitive and any acceptable solution requires a tradeoff among them. A hybrid approaches is proposed. In the first stage, a Non-dominated Sorting Genetic Algorithm II (NSGA II) is employed to approximate the set of Pareto solution through an evolutionary optimization process. In the subsequent stage, a multi-attribute decision making (MADM) approach is adopted to rank these solutions from best to worst and to determine the best solution in a deterministic environment with a single decision maker. The ranking of Pareto solution is based on entropy weight and TOPSIS method. A turbine PID design example is conducted to illustrate the analysis process in present study. The effectiveness of this universal framework is supported by the simulation results.

Due to the limited capacity of cotton-processing factory, machine-collecting cannot make sure the process progressing in time and will cause a bad heat dissipation of cotton or a high temperature and humidity. A cotton temperature and humidity wireless monitor is designed to solve the problem. In our experiment, we find that the collecting holes of the collecting tube play the most important part in the data collection. Comparison is made about the performance between round holes and diamond holes using FLUENT, we get the result that the diamond holes have a better collecting effects and a higher collecting accuracy.

A new synthesis of spirocyclic oxindole analogue spiro[piperidine-4,3′-pyrrolo[2,3-b]pyridin]-2′(1′H)-one 1is described. The key steps involve dialkylation of arylacetonitrile and cyclization of the azaoxindole ring by an intramolecular Buchwald–Hartwig amidation of carboxylic amide and aryl chloride. A small library was obtained by reductive amination of 1with various aldehydes and was screened against human lung cancer cell A549, human liver cancer cell BEL7402, and human colon cancer cell HCT-8. The results show that most of the library compounds 2have some inhibitory activities. 2-(Trifluoromethoxy) benzylic substituted spirocyclic azaoxindole 2ewas identified as a nanomolar inhibitor against human lung cancer cell A-549 (IC50=50nmol/L).

An improved and scalable process for substituted 3,8-diazabicyclo[3.2.1]octane was developed. N-Benzyl-2,5-dicarbethoxy-pyrrolidine 2was reduced to N-benzyl-2,5-dihydroxymethylpyrrolidine 9and subsequently debenzylated to afford N-Boc-2,5-dihydroxymethylpyrrolidine 10. After mesylation of the diol 10and cyclization with benzylamine, a diversity of scaffold, 3,8-diazabicyclo[3.2.1]octane analogue 12was obtained in a total yield of 42% in five steps.

The interaction between H2S and oxygen vacancy on the anatase TiO2(101) surface has been theoretically studied by using first-principles calculations. On one hand, it is found that the relative stability of the subsurface and surface VOcould be reversed by H2S adsorption, and the surface VObecomes energetically more favorable than the subsurface VO. Meanwhile, the adsorption of H2S also can efficiently facilitate VOdiffusion from the subsurface layer to the surface layer. On the other hand, the results show that both the subsurface and the surface VOs can facilitate the H2S dissociation. Subsurface VOcan facilitate the H2S dissociation directly. In contrast, the H2S dissociates on the surface with surface VOby two indirect pathways. Specifically, after H2S dissociation on the surface with surface VO, the adsorption of the two complete dissociative H2S are energetically more stable than that of the surface with subsurface VO, and the sulfur atoms from H2S fill in the surface VOsite and form stable S-doped TiO2surfaces. This conclusion reveals the essential interaction between H2S and a subsurface oxygen vacancy, which may provide a possible way to illuminate the origin of the photocatalytic activity of the anatase TiO2(101) surface, and offers a possible method to obtain the S-doped TiO2surface.