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Urban lake eutrophication, largely driven by overflow wastewater, plays a pivotal role in precipitating algal proliferation due to heightened nitrogen levels in aquatic ecosystem. In addressing this question, this study investigated the chloride-mediated electrochemical oxidation system as a promising solution for controlling nitrogen contamination in overflow wastewater and inhibiting algal proliferation in wastewater-receiving urban lakes, and also evaluated the influence of essential operational parameters on the performance of system. The results indicated that, under the environmental conditions set by this experiment, the removal efficiency ranges of ammonia nitrogen and total nitrogen were 14.91 % - 100 % and 13.98 % - 99.62 %, respectively; meanwhile, the maximum algae inhibition rate could reach 100 % at a capacity ratio of 0.01. Response Surface Method analysis highlighted current density as the preeminent factor in nitrogen removal and algae inhibition, surpassing the influence of initial chloride ion and nitrogen concentrations within the system. Notably, an excessive current density could inadvertently lead to the nitrate nitrogen accumulation (up to 29 %), thereby diminishing the total nitrogen removal efficiency, particularly in low nitrogen-concentrated overflow wastewater scenarios. With respect to algae inhibition, a direct correlation was identified between higher residual total chlorine concentrations in the receiving lake and increased algae inhibition rates (R = 0.90, P < 0.05), and the residual total chlorine was found to exert pronounced inhibition on cyanobacteria compared to other algal forms. However, caution was advised regarding potential algal growth stimulation if the initial received total chlorine concentration in the urban lake receiving wastewater below 0.5 mg/L. These findings not only affirm the feasibility of this synergistic approach but also elucidate critical aspects for process optimization and control.

Background: The development and popularization of the Internet provides an important opportunity to advance national strategies for healthy aging, particularly the impact of the Internet on cognitive function in middle-aged and older adults.Objective: This study aimed to quantify the impact of Internet use on the cognitive health of middle-aged and older adults (aged≥45 years).Methods: We used data from the Chinese Family Panel Study (CFPS) survey, tested the robustness of the baseline findings by variable substitution and instrumental variables methods, and analyzed heterogeneity. Subsequently, five purposes of Internet use that affect cognitive function were analyzed in depth.Results: Internet use may improve cognitive function in middle-aged and older adults. The effect of Internet use on cognitive function was more pronounced in the lower age group (45–59 years), among males, in rural areas, and among middle-aged and older adults with higher levels of education. Cognitive functioning of middle-aged and older adults varied according to how often they used the Internet for entertainment, socialization, study, work, and business activities.Conclusions: The use of the Internet may be considered a practical non-pharmacological intervention to slow cognitive decline in middle-aged and older adults.

Knowledge related to photochemistry has been gradually introduced as a part of chemistry courses at both undergraduate and postgraduate levels. However, due to their complex conceptual principles, limited class time, and tedious experimental setup and methodologies, students tend to encounter difficulties in understanding the concepts and comprehending the applications of fluorescence in their daily lives. Hence, developing effective multidisciplinary approaches to help students understand such intricate and complicated concepts remains a focus for most chemistry educators. In this study, we demonstrated the introduction of the excitation–emission matrix and how it can be used to monitor the effect of thermal treatment on different olive oils viathe fluorescence fingerprinting method. The heating effect on the fluorescent properties of three olive oils, including extra virgin olive oil, refined olive oil, and blended olive oil, was discussed in a multidisciplinary approach that incorporates mathematical analyses. A speed-reading-based informative questionnaire survey was also conducted on students to investigate whether this method was effective in aiding students to better understand the physical significance of the excitation–emission matrix and its relevance to their daily lives. The acceptability and extensibility of this method were further evaluated by the student’s performance in this survey.

Objectives: Cyclosporin is one of the therapeutic regimens for hemophagocytic lymphohistiocytosis (HLH); however, the optimal dosage of cyclosporine in children with HLH is unknown. It has been found that piperacillin-tazobactam affects the cyclosporine pharmacokinetic process in pediatric HLH patients. Thus, the purpose of the present study was to recommend cyclosporin dosage for pediatric HLH with and without piperacillin- tazobactam.Methods: A previously established cyclosporine population pharmacokinetic model for pediatric HLH patients has been used in this study to recommend optimal dosage based on Monte Carlo simulation. The pediatric HLH patients have been included in eight weight groups (5, 10, 20, 30, 40, 50, 60, 70 kg) for sixteen dosages (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 mg/kg), split into one dose or two doses.Results: The optimal cyclosporin dosages for children having HLH without piperacillin-tazobactam have been found to be 15, 13, 12, 11, 10, and 9 mg/kg, split into two doses for weights of 5-7, 7-10, 10-20, 20-28, 28-45, and 45-70 kg, respectively. For children with HLH, optimal cyclosporin dosages with piperacillin-tazobactam have been found to be 8 and 7 mg/kg, split into two doses for weights of 5-20 and 20-70 kg, respectively.Conclusion: It is the first time that the cyclosporin dosage regimens for HLH in children have been developed based on Monte Carlo simulation, and the initial dosage optimizations of cyclosporine in pediatric HLH patients have been recommended.

ABSTRACTOff-target biodistribution of biologics bears important toxicological consequences. Antibody fragments intended for use as vectors of cytotoxic payloads (e.g. antibody-drug conjugates, radiotherapy) can accumulate at clearance organs like kidneys and liver, where they can cause dose-limiting toxicities. Renal and hepatic uptakes are known to be affected by protein electrostatics, which promote protein internalization through pinocytosis. Using minibodies as a model of an antibody fragment lacking FcRn recycling, we compared the biodistributions of leads with different degrees of accumulation at the kidney and liver. We identified a positive electrostatic patch highly conserved in a germline family very commonly used in the humanization of approved biologics. Neutralization of this patch led to a drastic reduction in the kidney uptake, leading to a biodistribution more favorable to the delivery of highly cytotoxic payloads. Next, we conducted a high throughput study of the electrostatic properties for all combinations of VH and VL germlines. This analysis shows how different VH/VL combinations exhibit varying tendencies to create electrostatic patches, resulting in Fv variants with different isoelectric points. Our work emphasizes the importance of carefully selecting germlines for humanization with optimal electrostatic properties in order to control the unspecific tissue uptake of low molecular weight biologics.

Introduction: Contamination of large grit sandblasting and acid-etching (SLA) with hydrocarbons make the surface hydrophobic and influence its bioactivity. Preservation in dH2O (modified SLA, modSLA) and ultraviolet (UV) irradiation were proven to be effective in decreasing hydrocarbon contamination and keeping the SLA surface hydrophilic.Aims: The aim of this study was to detect the in vitro bioactivity of SLA, modSLA and UV-SLA surfaces.Design: The SBF model was used to compare the bone-like apatite forming ability.Setting: The experiment was conducted at Southern Medical University.Materials and methods: The quantity of apatite was assessed by SEM and weighed on an electronic balance. The elemental composition and crystal phase were assessed by EDS and XRD analysis, respectively.Results: The sediments that completely covered the modSLA and UV-SLA surfaces after 4 weeks of soaking reached 3.23 ± 0.35 mg and 2.13 ± 0.95 mg, respectively. They were eight- and five-fold than that on the SLA surface (0.43 ± 0.15 mg) with statistical significance (p< 0.05 and p< 0.01, respectively). EDS and XRD tests recognized the sediments on the modSLA and UV-SLA surfaces as apatite with similar elemental compositions, Ca/P ratios and crystal phases.Discussion: Hydrophilicity and abundant hydroxyl groups drive modSLA and UV-SLA surfaces to absorb more Ca2+to accelerate the formation of apatite.Conclusion: SLA preservation in dH2O and UV irradiation were recognized as trustworthy methods to acquire greater bioactivity of the SLA surface.

A cost-effective technique to dissipate the energy in hydropower systems is the formation of a swirling flow within a tunnel. In such flows, an air core with a significant cross section usually occurs. To reveal the air-core features in the horizontal tunnel of a high-head shaft spillway, laboratory tests, numerical modeling, and prototype observations are performed, to examine issues such as the formation of the air core, the interjacent air motion, the air-carrying capacity, and the scale effects. It is shown that the shape of the air core varies greatly in the axial and radial directions along the tunnel and that the center of the core deviates from the axis of the tunnel. The motion of the air within the core is caused by the combined action of the water entrainment on the inner surface of the swirling flow and the axial pressure difference in the air core. The aeration process can be divided into five processes with respect to the changes of the gate openings. A theoretical expression is established for the air-carrying capacity of the swirling flow. The vacuum degree is the similarity condition of the air-carrying capacity of the swirling flow between the model and prototype tests based on the Froude law of the similitude, and this similarity condition is verified by both the model and prototype results. This work provides a reference for the application of the swirling flows in horizontal hydropower tunnels.

In order to ensure the stable operation of the wall-climbing robot on the ship's complex curved wall surface, analysis and optimisation method of non-contact permanent magnet adsorption unit is discussed in this paper. The influence of magnet arrangement, coupling, air gap distance and other factors on the adsorption force is analysed by finite element simulation software, and the parameter magnet-to-mass ratio is introduced to quantitatively compare these schemes. In the two scenarios of planar wall and curvature-varying wall, the structural parameters of the Halbach array are optimised with the maximum magnetic-to-mass ratio as the optimisation objective, and the ratio of adsorption force variation is proposed as the reference of design to ensure the performance of the adsorption unit on the variable-curvature wall. The running stability of the wall-climbing robot with designed magnetic adsorption unit is verified by experiments on the wall with varying curvature.

Common fragile sites (CFSs) are genomic loci prone to the formation of breaks or gaps on metaphase chromosomes. They are hotspots for chromosome rearrangements and structural variations, which have been extensively implicated in carcinogenesis, aging, and other pathological processes. Although many CFSs were identified decades ago, a consensus is still lacking for why they are particularly unstable and sensitive to replication perturbations. This is in part due to the lack of high-resolution mapping data for the vast majority of the CFSs, which has hindered mechanistic interrogations. Here, we seek to map human CFSs with high resolution on a genome-wide scale by sequencing the sites of mitotic DNA synthesis (MiDASeq) that are specific for CFSs. We generated a nucleotide-resolution atlas of MiDAS sites (MDSs) that covered most of the known CFSs, and comprehensively analyzed their sequence characteristics and genomic features. Our data on MDSs tallied well with long-standing hypotheses to explain CFS fragility while highlighting the contributions of late replication timing and large transcription units. Notably, the MDSs also encompassed most of the recurrent double-strand break clusters previously identified in mouse neural stem/progenitor cells, thus bridging evolutionarily conserved break points across species. Moreover, MiDAseq provides an important resource that can stimulate future research on CFSs to further unravel the mechanisms and biological relevance underlying these labile genomic regions.

In order to make micro composite drills (Fig. 1), cemented tungsten carbide (WC-10Co) and high strength (AISI 4340) steel were successfully bonded by hot compaction diffusion bonding at a low temperature. The effects of holding time, pressure and temperature on microstructure and mechanical properties of the sintered carbides and bonding strengths of the bimetallic composites were examined, and a transitional layer was found at the interface as a result of elemental inter-diffusion. The optimal bonding parameters were determined to achieve the maximum bonding strength of 226 MPa of the WC-10Co/AISI 4340 steel joints, which is helpful in producing micro composite drills. Microforming is introduced to produce lighter and more energy effective products. In this study, Magnesium-Lithium (Mg-Li) alloy, new material in microscale, was chosen to superior formed micro-cup due to its ultralight weight with outstanding ductility. The dry and oil lubrication conditions were chosen as benchmarks to investigate effects of a novel oil-based nanoparticle lubricant in micro deep drawing (MDD) process of Mg-Li alloy. Finite Element (FE) modelling was conducted and the simulation results of the drawing force were in a good agreement with the experimental results. The formed cup quality with consideration on the surface roughness has been extensively evaluated and the results illustrated the quality improvement was substantial.

To investigate the mechanism by which total alkaloids of Sophora alopecuroides(TASA) and matrine (MT) impair biofilm to increase the susceptibility of Staphylococcus epidermidis(S. epidermidis) to ciprofloxacin.

Autotaxin (ATX) is the dominant catalytic enzyme accounting for the lipid mediator lysophosphatidic acid (LPA) through hydrolysis of lysophosphatidylcholine (LPC). There is great interest in developing nonacidic ATX inhibitors with a specific binding mode to serve as potential in vivoeffective therapeutic tools. Herein, dating from a high-throughput screening (HTS) product Indole-1(740 nM), a dedicated optimization campaign was implemented through derivatizing the −COOH group to versatile linkers that well-bridged the indole skeleton and the hydrophobic pocket binding groups. Ultimately, it was established that the coexistence of a carbamate linker and −OH-group-containing amines could generally furnish excellent indole-based ATX inhibitors with even below 1 nM in vitroactivities. Two optimal entities were advanced to a bleomycin-induced mice pulmonary fibrosis model, which exerted promising efficacy in alleviating the damaged lung texture caused by bleomycin exposure. The novel carbamate-containing indole-based ATX inhibitors with a concrete binding mode may contribute to the identification of potential therapeutic agents to intervene in fibrotic diseases.

A practical and highly efficient protocol for the production of Autotaxin (ATX) inhibitor Ziritaxestat (1) was described. The procedure began with a catalyst-free bicomponent cyclization for the construction of the imidazo[1,2-a]pyridine skeleton 16. Subsequently, a typical Curtius rearrangement of carboxylic acid 17followed by nucleophilic attacking of 3,5-dichlorobenzyl alcohol 18fled to the carbamate analogue 19f. N-methylated 20was readily deprotected through HBr/HOAc treatment, which further conveniently took part in an alternative K2CO3-induced N-alkylation reaction with 9to give 10. 10coupled directly with piperazine to furnish 13, which ideally circumvent the removal of the Boc group. As a result, the hypertoxic KCN and the hypertoxic and costly isonitrile 3involved in the tricomponent cyclization were carefully avoided. Ultimately, a novel, scalable, and cost-effective route was favorably developed to afford Ziritaxestat in a 20.4% overall yield.

Rehmannia glutinosais an important Chinese medicinal plant with a severe consecutive monoculture problem which might be caused by Fusarium oxysporum. In this work, we isolated a bacterial strain DU-1 from the rhizosphere soil of R. glutinosa. The strain was identified as belonging to the genus Bacillusthrough 16S rDNA sequencing, and showed an antagonistic effect against F. oxysporum, indicating that it can inhibit the growth of F. oxysporum. Field experiments showed that the two bacterial agents (grown in bran and straw) consisting of DU-1 increased both biomass and effective compounds (catalpol and polysaccharide) of the monocropping R. glutinosa. Moreover, soil total nitrogen content was increased by 24.0% and 39.1%, respectively, indicating that the bacteria are involved in nitrogen fixation. Analysis of rhizosphere microbial communities also indicated that the agents significantly increased the abundance of genus Bacillusin R. glutinosarhizosphere, suggesting the bacteria can successfully colonize the rhizosphere soil and might play a positive role in improving R. glutinosagrowth. Furthermore, application of the agents reduced the diversity of soil rhizosphere microorganisms to a certain extent; however, it did not induce alterations in the predominant species. These results strongly indicate that the application of this bacterial strain may alleviate the consecutive monoculture problem of R. glutinosa.

Phase-frequency characteristics of approximate sinusoidal geomagnetic signals can be used for projectile roll positioning and other high-precision trajectory correction applications. The sinusoidal geomagnetic signal deforms in the exposed and magnetically contaminated environment. In order to preciously recognize the roll information and effectively separate the noise component from the original geomagnetic sequence, based on the error source analysis, we propose a moving horizon based wavelet de-noising method for the dual-observed geomagnetic signal filtering where the captured rough roll frequency value provides reasonable wavelet decomposition and reconstruction level selection basis for sampled sequence; a moving horizon window guarantees real-time performance and non-cumulative calculation amount. The complete geomagnetic data in full ballistic range and three intercepted paragraphs are used for performance assessment. The positioning performance of the moving horizon wavelet de-noising method is compared with the band-pass filter. The results show that both noise reduction techniques improve the positioning accuracy while the wavelet de-noising method is always better than the band-pass filter. These results suggest that the proposed moving horizon based wavelet de-noising method of the dual-observed geomagnetic signal is more applicable for various launch conditions with better positioning performance.

Computing-in-memory (CIM) is a promising approach to reduce the latency and improve the energy efficiency of deep neural network (DNN) artificial intelligence (AI) edge processors. However, SRAM-based CIM (SRAM-CIM) faces practical challenges in terms of area overhead, performance, energy efficiency, and yield against variations in data patterns and transistor performance. This paper employed a circuit-system co-design methodology to develop a SRAM-CIM unit-macro for a binary-based fully connected neural network (FCNN) layer of the DNN AI edge processors. The proposed SRAM-CIM unit-macro supports two binarized neural network models: an XNOR neural network (XNORNN) and a modified binary neural network (MBNN). To achieve compact area, fast access time, robust operations, and high energy-efficiency, our proposed SRAM-CIM uses a split-wordline compact-rule 6T SRAM and circuit techniques, including a dynamic input-aware reference generation (DIARG) scheme, an algorithm-dependent asymmetric control (ADAC) scheme, a write disturb-free (WDF) scheme, and a common-mode-insensitive small offset voltage-mode sensing amplifier (CMI-VSA). A fabricated 65-nm 4-Kb SRAM-CIM unit-macro achieved 2.4- and 2.3-ns product-sum access times for a FCNN layer using XNORNN and MBNN, respectively. The measured maximum energy efficiency reached 30.49 TOPS/W for XNORNN and 55.8 TOPS/W for the MBNN modes. [ABSTRACT FROM AUTHOR]

The detection of hypochlorite (ClO–) content in tap water is extremely important because excess amounts of hypochlorite can convert into highly toxic species and inadequate amounts of hypochlorite cannot fully kill bacteria and viruses. Although several metal–organic frameworks (MOFs) have been successfully employed as fluorescent sensors for hypochlorite detection, all these sensors are based on single emission that responds to the dose of hypochlorite. Ratiometric sensors are highly desirable, which can improve the sensitivity, accuracy, and reliability via self-calibration. Herein, a nanoscale dual-emission multivariate 5-5-Eu/BPyDC@MOF-253-NH2was synthesized by sequential mixed-ligand self-assembly and postsynthesis method. Among the two emission bands of 5-5-Eu/BPyDC@MOF-253-NH2, the strong blue emitting derived from ligands is sensitive to hypochlorite, while the red emitting derived from Eu(III) almost keeps invariable. Therefore, 5-5-Eu/BPyDC@MOF-253-NH2was exploited as a fluorescent ratiometric nanosensor for “on–off” sensing of hypochlorite. Notably, the proposed sensing system showed an excellent performance including fast response (within 15 s), relative high specificity, wide linear range (0.1–30 μM), and low detection limit (0.094 μM). Besides, the suppressed blue emitting was recovered after the addition of ascorbic acid (AA) that consumes ClO–via the redox reaction. Therefore, 5-5-Eu/BPyDC@MOF-253-NH2was further employed as a fluorescent ratiometric nanosensor for the “on–off–on” sensing of AA. This work represents the first MOF-based fluorescent “switch” for the ratiometric sensing of hypochlorite and the second for ratiometric sensing of AA.

A 50 mA CW deuteron RFQ is being built for a joint 973 project between Peking University and the Institute of Modern Physics. This RFQ adopts a high-frequency window-type structure. To study its RF properties and to validate the reliability of an electromagnetic simulation, two full-length aluminum models with tuners were built in succession. RF measurements were obtained from the test bench and compared to the simulations, including frequencies, quality factors, and electric fields of different modes and the field in aperture. Through field tuning, the maximal field unflatness for a single quadrant and the average asymmetry of four quadrants were reduced from 8.7% and $$\pm \,$$ ± 3.6% to 5.8% and $$\pm \,$$ ± 1.7%, respectively. Moreover, a tuning method of adjusting the gap distance between the endplates and the vanes was also studied in this paper.

High quality (200) and (111) orientations cubic MgZnO thin films were made on (200) and (111) orientations MgO substrates separately under different condition with higher and lower migration energy of reactive atoms separately. The crystal quality of (111) orientation MgZnO thin film is higher than (200) one because of the stronger horizontal migration of atoms on (111) surface under high temperature condition, the surface of (200) orientation MgZnO thin film is smoother than (111) orientation one because of lower vertical growth speed of (200) MgZnO grains. The band gap of (111) orientation MgZnO thin film is smaller than (200) one because of more Zn atoms in (111) orientation MgZnO lattice than that in (200) ones. This paper gives an effective method to improve crystal quality of different orientation MgZnO thin film under different condition, which is meaningful in application of cubic MgZnO in different areas.

Vascular smooth muscle cells (VSMCs) can transdifferentiate into macrophage-like cells in the context of sustained inflammatory injury, which drives vascular hyperplasia and atherosclerotic complications. Using single-cell RNA sequencing, we identify that macrophage-like VSMCs are the key cell population in mouse neointimal hyperplasia. Sex-determining region Y (SRY)-related HMG-box gene 10 (Sox10) upregulation is associated with macrophage-like VSMC accumulation and pyroptosis in vitroand in the neointimal hyperplasia of mice. Tumor necrosis factor α (TNF-α)-induced Sox10 lactylation in a phosphorylation-dependent manner by PI3K/AKT signaling drives transcriptional programs of VSMC transdifferentiation, contributing to pyroptosis. The regulator of G protein signaling 5 (RGS5) interacts with AKT and blocks PI3K/AKT signaling and Sox10 phosphorylation at S24. Sox10 silencing mitigates vascular inflammation and forestalls neointimal hyperplasia in RGS5 knockout mice. Collectively, this study shows that Sox10 is a regulator of vascular inflammation and a potential control point in inflammation-related vascular disease.

Previous studies showed that homocysteine (Hcy) could injure vascular endothelial cells via several mechanisms, including its promotion of oxidative stress pathway and endoplasmic reticulum stress (ERstress) pathway. Salidroside (SAL) is an active component of Rhodiola rosea with documented antioxidative properties. Emerging evidence conformed that SALattenuated Hcy‐induced endothelial dysfunction by reducing oxidative stress. However, its role in ERstress pathway remains unclarified. The purpose of this study was to explore the mechanism of the protective effect of SALon Hcy‐induced endothelial dysfunction. Pretreatment of the human umbilical vein endothelial cells (HUVECs) with SALsignificantly reduced the cell damage effects brought by Hcy in a dose‐dependent manner. Functional studies on the HUVECs found that SALrescued the endoplasmic reticulum stress induced by Hcy. The underlying mechanisms involve the inhibition of Hcy‐induced activation of binding protein (Bip) and C/EBPhomologous protein (CHOP), as well as the phosphorylation of protein kinase RNA‐like ERkinase (PERK) or inositol‐requiring enzyme 1 alpha (IRE1α). Taken together, these findings implicate that SALcould regulate ERstress pathway on the viability of endotheliocyte induced by Hcy in vitro. Our findings provide the first evidence that SALplays an important role in endotheliocyte protection via suppressing ERstress pathway in HUVECcells and that it may be a promising therapeutic target for atherosclerosis and cardiovascular disease.

MgxZn1–xO thin films were deposited on fused quartz substrate by PLD method with Mg0.4Zn0.6O source target, and the effect of the substrate surface atom constitution and the migration characteristics of reactive atoms on crystal structure of the MgZnO thin films were studied. Under oxygen-deficient condition, MgxZn1–xO thin film deposited mainly along (200) orientation of cubic structure lattice at temperature below 350 °C because of the alternatively constituted substrate surface by Si and O atoms and the weak horizontal migration of reactive atoms, mix-constituted substrate surface(Si/O areas and O-rich areas) and the intense horizontal migration of reactive atoms introduced phase separation in MgxZn1–xO thin films deposited at higher temperature. Single cubic structure (200) Mg0.38Zn0.62O thin films was made at 300 °C with Zn composition over theoretical limit in bulk materials, the band gap of which reached 4.2 eV and the MgZnO thin film could detect 330 nm near-UV light. And the available UV range of the cubic MgxZn1–xO thin film deposited at 350 °C was widened to 348 nm near-UV light because of the cubic MgZnO grains with even higher Mg composition in this sample. Under high temperature and oxygen flow rate condition, MgxZn1–xO thin film deposited mainly along the (200) orientation of cubic structure lattice at 2 Pa pressure, MgxZn1–xO thin film deposited mainly along the (111) orientation of cubic structure lattice on O-rich substrate surface when the migration energy of reactive atoms is extremely small at 10 Pa oxygen pressure, and both mix-constituted substrate surface and medium migration energy of reactive atoms cause the phase separation occurred in MgxZn1–xO thin films deposited under medium oxygen pressure. On the basis of the different substrate surface atom constitution and different migration characteristics of reactive atoms considering particular deposition method and condition, some previous results on the formation of different structure MgxZn1–xO thin films and phase separation could also be interpreted. So the available UV range of cubic MgZnO thin film could be adjusted widely from near-UV (348 nm) to vacuum UV (<200 nm) range when both substrate surface atom constitution and migration characteristics of reactive atoms are suitable under given condition by multiple methods.

The paper established real-time computing algorithm of S Curve to control the process of acceleration and deceleration for step motor on the basis of a reasonable start frequency. Moreover, this paper used economic embedded ARM STM32F103RCT as the main control chip to control the step motor, which realized this designed real-time computing algorithm. Finally, the relevant testing indicated that the algorithm can realize the rapid response of start and stop for step motor, and can effectively avoid undesirable phenomenon of step losing, overshoot and oscillation.

For MEMS (Micro-Electro-Mechanical System) inertial sensor low precision, high noise and the characteristics of the gyroscope error accumulating, this paper designed a kind of yaw angle measuring system based on EKF (Extended Kalman Filter) by STM32 microcontroller and MEMS sensor. The EKF applys the attitude angle quaternion as the filter state variable, the angular rate as the filter time update. And application of the carrier location's gravitational field and geomagnetic data, complete filter measurement update, suppress divergent attitude error, obtain high accuracy and reliability of the attitude angle (pitch angle, roll angle, yaw angle) data. Experimental results show that the practical application of error control heading within ± 1º, with high practical value.

Noble-metals with carbon-based support remains a typical catalyst in fuel cell applications, but their fabrication is usually complicated and energy intensive. In this work, Shewanellacells are used as an environmentally friendly factory for nano-sized Pd preparation and a precursor for multifunctional carbon support with functionalized surface and heteroatom dopant. With simple KOH activation at 420°C, a highly-porous heteroatom-doped carbon with well-dispersed Pd nanoparticles was derived from the microbial cells. The as-synthesized material exhibited a 2.2-times larger specific mass catalytic activity (at −0.1V vs. Ag/AgCl) towards oxygen reduction reaction, better durability and higher methanol tolerance than commercial Pt/C catalyst. Density functional theory calculations provide a molecular-level insight into the ORR mechanism, and suggest that its great catalytic activity was ascribed to the high reactivity of Pd4cluster and the N- and O-doped carbon support with vacancy. This work opens a facile, low-cost and eco-friendly approach for hybrid electrocatalyst preparation and provides implications for the expanded application of biogenic nano-sized metal nanoparticles.

Analgin is a widely used medicine for its significant effect, convenience and low price. At present, there still exist some problems concerning the production process. The purpose of this work is to investigate present situation of analgin preparation, the disadvantages and existing problems, to discuss the possibility to optimize the process. An efficient approach to improve the process is to remove 4-aminoantipyrine sulfate related materials by extraction, which simplified the post-processing, greatly increased analgin crystallization rate, and reduced mother liquor quantity.

In the process of imaging, digitalization and transmission, images are generally contaminated by Gaussian noise and salt & pepper noise, which cannot be eliminated completely at the same time only by Mean filter or Median filter. Aiming at solving this problem, an improved hybrid median-mean filter algorithm based on the Improved Median Filtering (IMF) algorithm is proposed in this paper. The experimental results show that the new algorithm shows better performance than either Median filtering algorithm or Mean filtering algorithm, which can not only get rid of Gaussian noise and salt & pepper noise simultaneously, but also minimize the contradictions between noise erasing and image details protecting effectively.

Reduced graphene oxide (rGO) supported palladium nanoparticles (Pd NPs) with a size of ∼3 nm were synthesized using one-pot photoassisted citrate reduction. This synthetic approach allows for the formation and assembly of Pd NPs onto the rGO surface with a desired size and can be readily used for other metal NP preparation. The prepared rGO-Pd exhibited 5.2 times higher mass activity for ethanol oxidation reaction than the commercial platinum/carbon (Pt/C). In the oxygen reduction reaction tests, rGO-Pd exhibited comparable activity compared with Pt/C and maintained its high performance after 4000 cycles of potential sweep. These results demonstrate that our synthetic approach is effective for preparing graphene-supported metal NPs with excellent activity and stability in ethanol oxidation and oxygen reduction reactions.

To minimize the deficiency of the existing indoor location methods for mobile robots, the RSSI (received signal strength indication) model of WLAN is established. Then a combined location method for mobile robots based on DR (dead reckoning) and WLAN is proposed, which employs PMLA (probability matching location algorithm) and KF (Kalman filter) for information fusion. Simulation results reveal that the combined location approach works well in eliminating the cumulative error of DR and reducing the fluctuation of WLAN location. As a result, the proposed method is capable of enhancing the positioning accuracy of mobile robots to a certain extent, promising a low-cost and reliable location scheme for its development.

As the key equipment in coal-fired power plants, the optimal control problem of ball mill is an important factor affecting the efficient operation of the mill. In this paper, the output model, energy consumption model and unit consumption model of coal pulverizing system are built on the basis of analysis of ball mill running condition. The unit consumption model is used as the genetic algorithm fitness function. The outlet temperature, practical ventilation and coal load of ball mill are chosen as the optimization variables. The algorithm model is built to solve the multi-objective problem of ball mill.

To forecast the dynamic responses of closed high-speed precision press accurately, a 3-degree-of-freedom (DOF) dynamic model of mass-spring damping is proposed in this work. This model operates by using the centralized parameter method. Considering the instantaneity of impact load, we employ impulse simulation to simulate the periodic impact working conditions of a JF75G-200 high-speed press using both 2-DOF and 3-DOF models. Simulation data on the dynamic responses of the press are acquired and compared with the results from on-site measuring. The proposed 3-DOF dynamic model of mass-spring damping has been proven by our simulation and test to be reliable as well as effective for detecting the dynamic responses of the press.

Abstract: This paper is concerned with a Lotka–Volterra competition system with spatio-temporal delays. By using the linearization method, we show the local asymptotic behavior of the nonnegative steady-state solutions. Especially, the global asymptotic stability of the positive steady-state solution is investigated by the method of upper and lower solutions. The result of global asymptotic stability implies that the system has no nonconstant positive steady-state solution. [Copyright &y& Elsevier]

In present study, the mechanical properties of disc-spring vibration isolator with viscous dampers is investigated by finite element analysis (FEA) and experiments. The result of FEA and static test reveals that frictional damping has significant effect on the static stiffness of combination vibration isolator, the ability to strengthen loading stiffness and lower unloading stiffness. However viscous damper has no effect on the static mechanical properties. The dynamic experiment shows that the dynamic performance of combination vibration isolator can be greatly improved with viscous dampers. Viscous dampers have little effect on dynamic stiffness of vibration isolator, but significant effect on damping characteristics. These conclusions are of significant importance in the analysis and design of combination disc-spring vibration isolators.

Al–Si eutectic growth mechanism was investigated in a directionally-solidified Al–13 wt% Si alloy with different strontium (Sr) and magnesium (Mg) additions, growth velocities and temperature gradients. Macro- and micro-scale metallographic analyses revealed that addition level of Sr and Mg, temperature gradient and growth velocity are important factors affecting stability of solidifying Al–Si eutectic front and the final morphology of eutectic grains in the solidified Al–13 wt% Si alloys. By varying (tailoring) these factors, a variety of eutectic grain structures and morphologies such as planar front, cellular structure, a mix of cellular and columnar, or equiaxed dendrites, can be obtained. Increasing temperature gradient, reducing growth velocity, or decreasing Sr and Mg contents is beneficial to stabilizing planar growth front of eutectic grains, which is qualitatively in accordance with constitutional supercooling criterion for binary eutectic growth. In contrast, adding more Sr and Mg, increasing growth velocity, or decreasing temperature gradient produces large constitutional supercooling, leading to columnar-equiaxed transition (CET) of eutectic structure, which can be interpreted on the basis of Hunt's Model. It is also found that both solute concentration and solidification variables have significant impact not only on eutectic growth, but also on gas porosity formation. [Copyright &y& Elsevier]

Workability, strength and fracture mechanics of polypropylene macro-fiber reinforced Reactive powder concrete (RPC) were studied in this work. The results showed that the incorporation of macro-fiber could influence the workability of RPC, the slump of RPC decreased with the increasing of macro-fiber content; compressive strength decreased while splitting strength increased with the increasing of macro-fiber, meanwhile the flexural strength invariant. Macro-fiber could strongly enhance the flexural toughness of RPC and changed the failure mode from brittle to ductile; fracture energy tends to increase linearly with the increasing of macro-fiber.

This study is focused on the mechanical properties and buffer performance of the disc-spring vibration isolator combined with polyurethane (PU) pieces. Finite element model of the isolator, considering the effect of the friction, is established and then simplified by those of its isolation components. Simulation results verified by the experiment reveal that PU piece is capable of lowering the dynamic stiffness of disc springs whilst keeping their static stiffness nearly constant. A mathematical model of the isolator is also built to research the vibration isolation and buffer performance of the variable stiffness vibration isolator. Analysis results indicate that the variable stiffness vibration isolator has a better buffer performance than the constant one. And it also reveals that an optimal damping ratio for the vibration isolation system exists under the same impact force. Our findings are supposed to provide theoretical basis for the design of new combination isolators.

An approach called pseudo-peripheral was utilized to determine the starting cell for the Reversed Cuthill-McKee (RCM) algorithm. Then this approach was validated in a cavity domain, and consequently showed high efficiency during the renumber procedure. With such rapid renumber method, an implicit computational aerodynamic solver was established. The results of flow around wing NACA0012 reflected that the aerodynamic solver is efficient and accurate enough for engineering application.

The characteristics and the design factors of wireless sensor network node are talked in this article. According to the design factors of wireless sensor network, this article will mainly point out the design of wireless sensor nodes based a Cortex-M3 Microcontroller STM32F103RE chip. And the wireless communication module is designed with a CC2430 chip. Our wireless sensor node has good performance in our test.

In the control process of trajectory correction projectile, a real-time accurate measurement of projectile roll angle information is required. Geomagnetic and GPS measurement principle is applied for the establishment of the projectile measured roll angle combinations mathematical calculation model, the designing of MR and GPS measuring circuits, and derivation of the singular points of the system and error resolution type. Numerical simulation methods are applied to verify the location of singular points of the combination of measurements and the linear spline combination of interpolation method of compensation the position of the magnetic vector error and the ellipsoid fitting calibration algorithm compensate for magnetic measurement error. The geomagnetic error has less effects on the combination of measured roll angle error, while the pitch angle and yaw angle error has greater impact on the roll angle error. Remove the singular point area, projectile roll angle error is less than 2°when measured by the combination of MR / GPS .

Phase shift laser range finder, as a large-scale, high-precision measurement method, is widely used in industrial and military fields. The traditional laser range finder can not meet the need of real-time, high resolution measurement because of its low anti-jamming capability and time-consuming measurement. Owing to this, multi-channel transmitting and receiving system for phase shift laser range finder based on parallel DSP was designed. Multi-frequency modulation laser can be transmitted and received at the same time, improving the measurement speed and avoiding the wrong data fusion because of target moving. The distance was got by measuring the phase difference between the measurement signal and reference signal, and the Doppler velocity of the target is got by measuring the measurement signals frequency, The measurement signals reference signals were acquired by parallel AD convertors, the phase difference between them was calculated adopting all-phase FFT(apFFT). A new frequency correction method was proposed according to the amplitude spectrum acquired by apFFT, Amplitude spectrum is expanded into Taylor series and the correction value of frequency is calculated by relationship of spectrum lines. Monte Carlo simulation results proved that the new frequency correction method had higher resolution and better stability than Rife method and centro-baric method. The experiments is implemented on a precision guide of 3m-long, on the condition that the sampling frequency of AD converter is 937.5KHz, the apFFT transform point number is 4096, distance and velocity results can be obtained each 10ms, experiments prove that the distance measurement standard deviation better than 0.09mm and the velocity measurement standard deviation better than 0.022m/s are obtained. The system can meet the need of high accuracy ,real-time distance measurement of moving target.

This paper put forward a research of the chirp signal and its generated method. The research was based on a software-defined radio (SDR) system, which was composed of GNU Radio and Universal Software Radio Peripheral (USRP). It introduced the chirp signal and design algorithm to show how to generate the chirp signal based on DDS technique. And it provided two platforms including the FPGA platform and SDR platform to generate the chirp waveforms. Finally, it analyzed the difference between the two platforms. From the waveforms using these two platforms displayed in oscilloscope, it found that the results based on SDR were better. And it demonstrated that advantages of GNU Radio and USRP.

Surface plasmon enhanced differential reflectance (DR) technique has been theoretically investigated in this paper. A plasmonic gold grating substrate is proposed to greatly enhance the sensitivity of the DR technique. The results show that the sensitivity of the technique can be enhanced by at least one order of magnitude compared to that with SiO_2 substrate (dielectric substrate) and the enhancement effect is most significant for ultra-thin films with thickness of less than 1 nm. It is further demonstrated that the technique can be also used for detecting the refractive index change of thin films with a much enhanced sensitivity.

Here we propose a scheme utilizing the double plasmon modes of gold nanorod (GNR) to efficiently enhance the fluorescence of surrounding emitters. The transversal and longitudinal surface plasmon resonance (TSPR and LSPR, respectively) modes of GNR are simultaneously utilized to enhance the excitation and emission efficiency, respectively. To demonstrate the idea, GNRs coated with an Oxazine-725 dye molecule-doped silica shell are employed. For comparison, gold nanospheres with the same shell are also studied, of which the single plasmon resonance mode matches only with the excitation wavelength of Oxazine-725. The experimental results, in agreement with theoretical simulations using the discrete dipole approximation method, successfully demonstrate the efficient excitation and emission enhancement of fluorescence assisted by the double SPRs of GNRs.

It is necessary to establish a dynamic model to predict and evaluate the dynamic performance of closed high-speed press system during design procedure, when it is impossible to carry out the test of prototype. In this work, a dynamic model for the closed high-speed press system is developed to predict and evaluate its dynamic performance. Unlike in previous models where the press frame is considered to be a single mass and the effects of the transmission mechanism and complex frame structure are neglected, the present model can be used to analyze the dynamic response of a multi-body vibration-impact system treating it as a coupled one. The simulation results reveal that the dynamic responses of press under piling condition include a transient impact and a free vibration process. The vibration acceleration and velocity curves of the upper beam of the closed high-speed press decrease with the increasing speed of rotation. In contrast, vibration acceleration and velocity curves of the lower beam of the press increase with the increasing rotation speed. The experimental results demonstrate that the dynamic model proposed herein is consistent with the actual working state of the closed high-speed press and the validity of the dynamic model is verified.

Aim:Accumulating evidence suggests that endoplasmic reticulum (ER) stress plays a fundamental role in the initiation and development of atherosclerosis. Atorvastatin is known to exert pleiotropic effects on cardiovascular system. This study was designed to examine the effect of atorvastatin on homocysteine (Hcy)‐induced activation of ER stress and the potential mechanisms regarding AMP‐activated protein kinase (AMPK). Methods and results:Apolipoprotein E‐deficient (apoE−/–) mice were administrated with methionine or atorvastatin and sacrificed 2 months later for plasma tests and immunohistochemical analysis. To further study the mechanisms, human umbilical vein endothelial cells (HUVECs) were incubated with various concentrations of Hcy for 1 h, or 500 μmol/L Hcy for 1–24 h. Furthermore, we challenged HUVECs with Hcy in the presence or absence of atorvastatin, 5‐amino‐4‐imidazolecarboxamide riboside‐l‐beta‐D‐ribofuranoside (AICAR), an AMPK agonist, and AMPK‐DN that expressed a dominant‐negative mutant of AMPK. Expression levels of ER stress markers were measured by real‐time PCR and Western blot analysis. Our data revealed that atorvastatin prevented Hcy‐induced ER stress in the aortic roots of hyperhomocysteinemic mice. In vitrostudy showed atorvastatin suppressed Hcy‐induced ER stress in HUVECs as well. AICAR is found to have the same effect as that of atorvastatin, which could be antagonized by AMPK‐DN. Conclusions:Atorvastatin inhibits Hcy‐induced ER stress both in vitroand in vivo. The protective effect of atorvastatin against Hcy‐induced vascular injury is mediated by AMPK activation.

Past thermal experience is related to the memory and seems to be responsible for the changes in people’s expectations. In order to investigate how the previously air conditioned exposure impacts thermal perception in semi-outdoor spaces, the controlled experiments were conducted, with a total of 36 undergraduates who participated as the subjects. Based on the controlled experiments, the impact of previous exposure temperature to air conditioning was examined. It was found that the previously air conditioned exposure temperature has impact on thermal perception in semi-outdoor spaces. Based on the experiments, it can be found that the impact of the air conditioned exposure temperature is not significant when the temperature difference between the air conditioned environments is about 2℃ or 3℃. However, the impact of the air conditioned exposure temperature appears significant when the temperature difference between the air conditioned environments is up to 5℃.

The modal analysis of composite thin-walled box beams with double-cell sections is carried out by the finite element software ANSYS. The finite element models are established first for the double-cell composite thin-walled box beams, then the vibration modes of two box beams: Circumferentially Uniform Stiffness (CUS) and Circumferentially Antisymmetric Stiffness (CAS) are calculated and analyzed. The effects of length-width ratio and width-height ratio on the natural frequency and the modal shape of the double-cell composite thin-walled box beams are discussed.

SiC nanoparticles were treated by hydrofluoric acid (HF) and then put into the formulation of tread compounds of tire. After being mixed fully in the open mill and vulcanized in the sulfuration machine, some rubber nanocomposites filled with SiC nanoparticles were finally prepared out. The SiC nanoparticle reinforced rubber composites were observed by Scanning Electron Microscope (SEM). It was found that SiC nanoparticles show good uniformity of dispersion and unobvious agglomeration of particles in rubber matrix after short-time treatment by HF, while they show bad uniformity of dispersion and obvious agglomeration of particles in rubber matrix after long-time treatment by HF.

We introduce a kind of entangled state—a photon-addition two-mode squeezed thermal state (TMSTS)—by adding photons to each mode of the TMSTS. Using the P-representation of thermal state, the compact expression of the normalization factor is derived, a Jacobi polynomial. The nonclassicality is investigated by exploring especially the negativity of Wigner function. The entanglement is discussed by using Shchukin–Vogel criteria. It is shown that the photon addition to the TMSTS may be more effective for the entanglement enhancement than the photon subtraction from the TMSTS. In addition, the quantum teleportation is also examined, which shows that symmetrical photon-added TMSTS may be more useful for quantum teleportation than the nonsymmetric case.