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In this study, BF2 complexes of pyridyl‐isoindoline‐1‐ones (BPIO) has been firstly designed and investigated as an excellent corrosion inhibitor for the mild steel in 1 M HCl. The corrosion protection properties of BPIO were studied by using a series of experiments. The results indicated BPIO has excellent inhibition performance, and inhibition efficiency of BPIO reached up to 96.6%. The effects of immersion temperature and time were investigated by weight loss experiments to evaluate the stability of adsorbed BPIO film in protecting steel surface. Based on potentiodynamic polarization studies, BPIO acted as one mixed‐type corrosion inhibitor with predominant anodic effectiveness, and its adsorption on the mild steel follows the Langmuir adsorption isotherm. The values of ΔGads suggested the adsorption of BPIO on the mild steel surface was through a combination of chemisorption and physisorption. The adsorption of BPIO molecules on the steel surface was further identified by the techniques of scanning electron microscopy (SEM) and X‐ray photoelectron spectroscopy (XPS). The quantum chemical calculations based on density functional theory (DFT) and molecular dynamics (MD) simulations were used to optimize the BPIO molecular structure and investigate the inhibitive properties on the theoretical level, which agreed well with the experimental results. Besides, BPIO has been used for the development of water soluble metal antirusting agent. [ABSTRACT FROM AUTHOR]

By virtue of its ultra-high strength, toughness and specific surface area, graphene oxide (GO) has been a research hotspot in nano-cement because of its excellent electrical, thermal and mechanical properties. The GO-cement composite owns greatly improved microstructure, and mechanical and permeability-related performances compared with plain cement. Clarifying the reinforcing mechanisms of GO on cementitious composites is a prerequisite for the large-scale application of GO in the cement industry. Hence, in this work, the effect of the GO nanosheets on the shear properties of the calcium silicate hydrate (C–S–H) composites and the corresponding reinforcing mechanisms were investigated using molecular dynamics (MD) simulations. The simulated results reveal that the orientation angle between GO nanosheets and C–S–H layers is a significant factor influencing the enhancing effects of GO on the shear behaviour of C–S–H/GO composites. As the orientation angle ranges from 30° to 60°, the shear strain would cause bending deformation of GO nanosheets in composites. The bent GO nanosheets then absorb the deformation energy in the system, effectively isolating the transfer of shear-induced force chains. The ultimate shear strength reaches about 861.2 MPa for the orientation angle equalling 30°, increasing 23.5% compared with that of plain C–S–H. The microstructural damage characteristics analysis further indicates that it is crucial to trade off the effective anchorage of GO nanosheets in C–S–H gel and the structural integrity of C–S–H matrix when using GO nanosheets to enhance the shear performance of C–S–H composites. We expect the findings from this work can enhance the understanding of GO-reinforced cementitious composites and assist GO-based cement design in future work. [ABSTRACT FROM AUTHOR]

The pathogenesis of microbial infections and sepsis is partly attributable to dysregulated innate immune responses propagated by late-acting proinflammatory mediators such as procathepsin L (pCTS-L). It was previously not known whether any natural product could inhibit pCTS-L-mediated inflammation or could be strategically developed into a potential sepsis therapy. Here, we report that systemic screening of a NatProduct Collection of 800 natural products led to the identification of a lipophilic sterol, lanosterol (LAN), as a selective inhibitor of pCTS-L-induced production of cytokines [e.g., Tumor Necrosis Factor (TNF) and Interleukin-6 (IL-6)] and chemokines [e.g., Monocyte Chemoattractant Protein-1 (MCP-1) and Epithelial Neutrophil-Activating Peptide (ENA-78)] in innate immune cells. To improve its bioavailability, we generated LAN-carrying liposome nanoparticles and found that these LAN-containing liposomes (LAN-L) similarly inhibited pCTS-L-induced production of several chemokines [e.g., MCP-1, Regulated upon Activation, Normal T Cell Expressed and Presumably Secreted (RANTES) and Macrophage Inflammatory Protein-2 (MIP-2)] in human blood mononuclear cells (PBMCs). In vivo, these LAN-carrying liposomes effectively rescued mice from lethal sepsis even when the first dose was given at 24 h post the onset of this disease. This protection was associated with a significant attenuation of sepsis-induced tissue injury and systemic accumulation of serval surrogate biomarkers [e.g., IL-6, Keratinocyte-derived Chemokine (KC), and Soluble Tumor Necrosis Factor Receptor I (sTNFRI)]. These findings support an exciting possibility to develop liposome nanoparticles carrying anti-inflammatory sterols as potential therapies for human sepsis and other inflammatory diseases. [ABSTRACT FROM AUTHOR]

[Display omitted] • The control of branching density and branching distribution in long-chain olefin polymerization are readily available by the modification of α-diimine Ni(II) catalysts. • The different coordination geometry of the catalysts was observed and Ni4 adopts a rare square planar geometry. • The semicrystalline polymer with good mechanical properties and the amorphous polymer could be prepared respectively using the catalyst with varied steric substituent. The tuning of polyolefin microstructure, including the branching density and branching distribution, through the ligand modification in transition metal-based catalysts has received considerable interest. In this work, we present the synthesis and characterization of a series of α-diimine Ni(II) catalysts containing bulky diarylmethyl moiety and varied steric substituents, and a systematic investigation on the catalytic behavior of these catalyst for 1-octene and 1-decene polymerization. Ni3 with ortho -diisopropyl substituents adopts a common distorted tetrahedral geometry, while a rare square planar geometry is observed for Ni4 with ortho -phenyl substituents. The ortho -substituent effect on the preference of insertion fashion (1,2 or 2,1-insertion) and chain-walking in long chain α-olefin polymerization is also established. Highly branched amorphous polyolefin can be obtained by the unsymmetrical catalyst with ortho -alkyl substituents (H, Me, iPr) in which the major 1,2-insetion pathway was observed, whereas moderate branched semicrystalline polyolefin can be produced by the unsymmetrical catalyst with ortho -phenyl substituents, which showed a significant increase in 2,1-insertion. Most interestingly, the branching distribution analysis through 13C NMR indicated that the polymer obtained by Ni3 gave the higher percentage of long-chain branches relative to methyl branches, while Ni4 afforded the polymer with methyl branches being predominant. These significant differences in coordination geometry and catalytic behavior between Ni3 and Ni4 may be associated with the unique steric congestion of the ortho -phenyl substituents. In particular, the comparative investigation of the mechanical properties of the polymers obtained by Ni3 and Ni4 was also performed. [ABSTRACT FROM AUTHOR]

In the present study, we reveal the potential of graphene kirigami (GK) as an ultra-permeable membrane for water desalination using molecular dynamics simulation. The results demonstrate that the GK membrane has superior performance in water permeance, obtaining over 103 L/m2/h/bar with 100% salt rejection. The theoretical efficiency of water permeance using GK membrane is 2.4–5.8 times higher than that of the nanoporous graphene membrane and 2–4 orders of magnitude higher than reported conventional reverse osmosis membranes. Due to the unique geometry of the kirigami structure, the GK membrane would form the adsorption channels to reduce the energy barrier during the desalination processes and guide water molecules to be filtered more effectively. Moreover, compared with the nanoporous graphene, the GK membranes do not have rigorous pore geometry restrictions for desalination and can be generated via mechanical deformation, which provides significant convenience for future applications in practical projects. [Display omitted] [ABSTRACT FROM AUTHOR]

• A novel strategy for oil-in-water droplet coalescence was proposed on basis of microchannel-structured anodes. • The microchannel enhanced droplet polarization to weaken the electrostatic repulsion. • The microchannel improved ∙OH utilization to decompose oil-water interface film. • Residence time was 48 times shorter than that of reported flat electrodes at similar COD removal. • Excellent stability and unique renewability performance were achieved. Electrochemistry is a sustainable technology for oil-water separation. In the common flat electrode scheme, due to a few centimeters away from the anode, oil droplets have to undergo electromigration to and electrical neutralization at the anodic surface before they coalesce into large oil droplets and rise to water surface, resulting in slow demulsification and easy anode fouling. Herein, a novel strategy is proposed on basis of a TiO 2-x /Ti anode with microchannels to overcome these problems. When oil droplets with several microns in diameter flow through channels with tens of microns in diameter, the electromigration distance is shortened by three orders of magnitude, electrical neutralization is replaced by polarization coupling ·OH oxidation. The new strategy was supported by experimental results and theoretical analysis. Taking the suspension containing emulsified oil as targets, COD value dropped from initial 500 mg/L to 117 mg/L after flowing through anodic microchannels in only 58 s of running time, and the COD removal was 21 times higher than that for a plate anode. At similar COD removal, the residence time was 48 times shorter than that of reported flat electrodes. Coalescences of oil droplets in microchannels were observed by a confocal laser scanning microscopy. This new strategy opens a door for using microchannel electrodes to accelerate electrochemical coalescence of oil-in-water droplets. [Display omitted] [ABSTRACT FROM AUTHOR]

The increasing prevalence of non-alcoholic fatty liver disease (NAFLD) poses a growing challenge in terms of its prevention and treatment. The 'multiple hits' hypothesis of multiple insults, such as dietary fat intake, de novo lipogenesis, insulin resistance, oxidative stress, mitochondrial dysfunction, gut dysbiosis and hepatic inflammation, can provide a more accurate explanation of the pathogenesis of NAFLD. Betaine plays important roles in regulating the genes associated with NAFLD through anti-inflammatory effects, increased free fatty oxidation, anti-lipogenic effects and improved insulin resistance and mitochondrial function; however, the mechanism of betaine remains elusive. [ABSTRACT FROM AUTHOR]

• TGF-β1 increased neuronal viability and inhibited apoptosis after trauma for 24 h. • TGF-β1 reversed the expression of Ca v 1.2, which was decreased after trauma injury. • TGF-β1 enhanced the trauma-injured neuro-2a intracellular Ca2+ concentration. • TGF-β1 increased the expression of Ca v 1.2 by activating the p38 MAPK pathway. Traumatic brain injury (TBI) is a leading cause of disability and death in adolescents, and there is a lack of effective methods of treatment. The neuroprotective effects exerted by TGF-β1 can ameliorate a range of neuronal lesions in multiple central nervous system diseases. In this study, we used an in-vitro TBI model of mechanical injury on murine primary cortical neurons and the neuro-2a cell line to investigate the neuroprotective role played by TGF-β1 in cortical neurons in TBI. Our results showed that TGF-β1 significantly increased neuronal viability and inhibited apoptosis for 24 h after trauma. The expression of Ca v 1.2, an L-type calcium channel (LTCC) isoform, decreased significantly after trauma injury, and this change was reversed by TGF-β1. Nimodipine, a classic LTCC blocker, abolished the protective effect of TGF-β1 on trauma-induced neuronal apoptosis. The knockdown of Ca v 1.2 in differentiated neuro-2a cells significantly inhibited the anti-apoptosis effect of TGF-β1 exerted on injured neuro-2a cells. Moreover, TGF-β1 rescued and enhanced the trauma-suppressed neuro-2a intracellular Ca2+ concentration, while the effect of TGF-β1 was partially inhibited by nimodipine. TGF-β1 significantly upregulated the expression of Ca v 1.2 by activating the p38 MAPK pathway and by inhibiting trauma-induced neuronal apoptosis. In conclusion, TGF-β1 increased trauma-injured murine cortical neuronal activity and inhibited apoptosis by upregulating Cav1.2 channels via activating the p38 MAPK pathway. Therefore, the TGF-β1/p38 MAPK/Ca v 1.2 pathway has the potential to be used as a novel therapeutic target for TBI. [ABSTRACT FROM AUTHOR]

Introduction: Acute traumatic intraparenchymal hematoma (tICH) expansion is a major cause of clinical deterioration after brain contusion. Here, an accurate prediction tool for acute tICH expansion is proposed. Methods: A multicenter hospital-based study for multivariable prediction model was conducted among patients (889 patients in a development dataset and 264 individuals in an external validation dataset) with initial and follow-up computed tomography (CT) imaging for tICH volume evaluation. Semi-automated software was employed to assess tICH expansion. Two multivariate predictive models for acute tICH expansion were developed and externally validated. Results: A total of 198 (22.27%) individuals had remarkable acute tICH expansion. The novel Traumatic Parenchymatous Hematoma Expansion Aid (TPHEA) model retained several variables, including age, coagulopathy, baseline tICH volume, time to baseline CT time, subdural hemorrhage, a novel imaging marker of multihematoma fuzzy sign, and an inflammatory index of monocyte-to-lymphocyte ratio. Compared with multihematoma fuzzy sign, monocyte-to-lymphocyte ratio, and the basic model, the TPHEA model exhibited optimal discrimination, calibration, and clinical net benefits for patients with acute tICH expansion. A TPHEA nomogram was subsequently introduced from this model to facilitate clinical application. In an external dataset, this device showed good predicting performance for acute tICH expansion. Conclusions: The main predictive factors in the TPHEA nomogram are the monocyte-to-lymphocyte ratio, baseline tICH volume, and multihematoma fuzzy sign. This user-friendly tool can estimate acute tICH expansion and optimize personalized treatments for individuals with brain contusion. [ABSTRACT FROM AUTHOR]

This article proposes a model-based voltage quality analysis and optimization method for post-fault reconfigured N-level Neutral Point Clamped (NPC) inverter. It is found that the voltage quality of post-fault reconfigured multilevel inverters (MLIs) has significant degradation which could cause issues in critical applications. To analyze and solve the voltage quality problem, existing voltage quality and mathematical analyses of MLIs were reviewed. Significant limitations of existing voltage quality analysis methods and shortages of existing mathematical analysis were found. Thus, a suitable mathematical model of N-level NPC inverter is proposed in this article to accurately describe voltage quality of a reconfigured N-level NPC inverter. The mathematical model is validated by simulation and experimental results and used for voltage quality analysis. In addition, based on the accurate mathematical model and results of voltage quality analysis, an optimization method is proposed to alleviate the voltage quality degradation of post-fault reconfigured N-level NPC inverter. A five-level NPC inverter and a reconfiguration method were used as an example to illustrate the proposed optimization method. Experimental and simulation results validate the effectiveness of the proposed optimization method. [ABSTRACT FROM AUTHOR]

Remote sensing has become an essential technique in water environment monitoring. However, the cloud contamination of remote sensing images breaks its spatial and temporal continuity in practical application. The current cloud removal algorithms always based on the hypothesis that the ground surface has no significant changes temporally, which is not proper for optically complex water body. Therefore, to overcome the weakness of current cloud removal algorithms on temporally fast-changing landscapes, a temporal unmixing-based cloud removal (TUBCR) algorithm is proposed to estimate the under-cloud information of optically complex water images. In this algorithm, the spatial information and temporal information were separated into temporal abundance images and temporal endmembers. By extracting the high temporal resolution endmembers, the fast-changing water information were estimated. The performance of the proposed algorithm was compared with those of two widely used cloud removal algorithms: the modified neighbourhood similar pixel interpolator (mNSPI) algorithm and the weighted linear regression (WLR) algorithm. The results of four simulated datasets (500 images in total) and two real Geostationary Ocean Colour Imager (GOCI) datasets (8 images in total) show that the proposed algorithm performed better in both quantitative indexes and visual effect compared with the mNSPI algorithm and the WLR algorithm. In satellite image time series, the proposed algorithm could accurately estimate under-cloud water information and correct the offsets of the statistical temporal trends that caused by cloud contamination. Hence, theoretically, the proposed TUBCR algorithm altered the similar pixel-based strategy of classic methods and got a satisfied performance in fast-changing water images. In applications, the TUBCR algorithm has great potential to improve the spatiotemporal coverage of optically complex water remote sensing. [ABSTRACT FROM AUTHOR]

Purpose: Nonalcoholic fatty liver disease (NAFLD) is currently the leading cause of chronic liver disease in developing countries. The pathogenesis is complex, and there is currently no effective treatment. Betaine is an essential intermediate in choline catabolism and an important component of the methionine cycle. Betaine deficiency is associated with NAFLD severity, and its mechanism needs to be further elaborated. Methods: In this study, an NAFLD mouse model was established by feeding ApoE−/− mice a high-fat diet. The effects of betaine on NAFLD were investigated, including its mechanism. Results: In this study, after treatment with betaine, blood lipid levels and liver damage were significantly decreased in the NAFLD mouse model. The fat infiltration of the liver tissues of high-fat diet (HFD)-fed mice after betaine administration was significantly improved. Betaine treatment significantly upregulated AMP-activated protein kinase (AMPK), fibroblast growth factor 10 (FGF10), and adipose triglyceride lipase (ATGL) protein levels both in vivo and in vitro and suppressed lipid metabolism-related genes. Furthermore, the overexpression of FGF10 increased the protein level of AMPK and decreased lipid accumulation in HepG2 cells. Conclusion: Taken together, the data strongly suggest that betaine significantly prevents high-fat diet-induced NAFLD through the FGF10/AMPK signaling pathway in ApoE−/− mice. [ABSTRACT FROM AUTHOR]

• The coating method assists the CNTs for good dispersion and is strongly connected to the surface of fly ash. • The coating method allows CNTs to concentrate in the ITZ between fly ash and cement particles. • The coated CNTs generate nucleation and pore-infilling effects to strengthen the ITZ in cementitious composites. • The workability of the CNTs-coated fly ash-modified cementitious grouting can be significantly reinforced. Cementitious composites reinforced with carbon nanotubes (CNTs) offer notable benefits compared to conventional cement-based materials in terms of durability and strength. Despite these advantages, the widespread implementation of CNTs in cement-based grouting engineering has not been carried out due to the limitations of dispersion issues. In order to facilitate the progression of carbon nanotubes (CNTs) from laboratory experiments to engineering applications, we proposed a method of using amino-functionalised functional groups to coat CNTs on the fly ash (FA) particles' surfaces to assist the dispersion and prepare cost-effective, low-carbon emission, energy consumption-saving and high-performance cementitious slurry. The experimental results exhibit that compared with plain cement-based grouting materials, incorporating 0.023 wt% CNTs and 14.3 wt% FA can reinforce the compressive and tensile strength by 14.2–25.8% and improve the workability by about 21.0%. The application of coated CNTs induces nucleation and pore-infilling effects within the interfacial transition zone (ITZ) of the cementitious composites. This action leads to a reduction in ITZ width and a decrease in crack occurrence within the ITZ. Consequently, these effects contribute to an augmentation in the consolidation strength of the slurry. Acoustic emission and fracture surface fractal analysis further reveal that incorporating CNTs enhances the resist-loading ability of the cement matrix by increasing its energy absorption capability. The innovative coating method reported in this work is expected to facilitate the future application of CNTs in practical grouting engineering. [ABSTRACT FROM AUTHOR]

An aldehyde with a cyclohexa‐2,5‐dienyl group in the α‐position is introduced as a storable surrogate of highly reactive acetaldehyde. The cyclohexa‐2,5‐dienyl unit is compatible with an enantioselective Michael addition to nitroalkenes promoted by a Hayashi–Jørgensen catalyst and can be removed by a boron Lewis acid mediated C−C bond cleavage. The robust two‐step sequence does not require a large excess of the aldehyde component that is typically needed when directly using acetaldehyde. [ABSTRACT FROM AUTHOR]

In the present work, using a high-resolution three-dimensional numerical analysis, the initiation and propagation mechanism of a detonation wave is studied in a circular tube with a hot jet initiation. The reactive Euler equations with a one-step two-species chemistry model are solved based on the structured adaptive mesh refinement technique. Influences of both a single hot jet and impinging double hot jets on the formation of the detonation wave are studied. For each case, the objective is to investigate the role of the tube wall on the initiation and propagation of the detonation wave. The result for both cases shows that the hot jet-induced bow shock forms a complex reflection structure in the circular tube. The reflection effect of the circular wall strengthens the shock and facilitates the formation of the Mach stem, which leads to the formation of the detonation wave. However, when the hot jet condition and the total area of jet hole remain the same, for the case of initiation using double hot jets, the reflection strength of the bow shocks weakens when the diameters of the hot jets become smaller. When using a single hot jet, the initiated detonation is overdriven and propagates in the two-headed mode. In this initiation mode, by increasing the inflow Mach number, a four-headed mode detonation front is formed, while in the case of impinging double hot jets, a four-headed mode detonation front is initiated directly. [ABSTRACT FROM AUTHOR]

This article proposes an unsupervised learning approach for fault prognosis of silicon carbide (SiC) mosfets. The proposed approach utilizes the changing trend of a device's voltage, current, temperature, and other device characteristics with its degradation. The failure modes of semiconductors are reviewed along with existing methods for fault prognosis. The proposed approach is the first to address prognostics of SiC devices, and it can avoid the effects from system noise and data errors. It is not limited to offline analysis and is targeted at online implementation. It is easy to implement on standard digital platforms, and has fast computational speed. Offline data analysis is performed to verify the effectiveness of the proposed method, and a processor-in-the-loop system is used to verify its ability to perform online fault prognosis. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of fault estimation and fault tolerant control for quadrotor unmanned aerial vehicle. Firstly, a robust adaptive fault estimation observer (AFEO) is proposed to achieve fault estimation of quadrotor with actuator fault in the presence of external disturbances and parameter uncertainties. Furthermore, based on the estimation of fault, a dynamic output feedback fault tolerant controller (DOFFTC) is designed to stabilise the closed-loop system with faults and uncertainties. Sufficient conditions for the existence of both AFEO and DOFFTC are given in terms of linear matrix inequalities. Finally, simulation results are presented to illustrate the effectiveness of the proposed strategy. [ABSTRACT FROM AUTHOR]

Introduction: In response to external stress, cells alter their morphology, metabolic activity, and functions to mechanically adapt to the dynamic, local environment through cell allostasis. To explore mechanotransduction in cellular allostasis, we applied an integrated micromechanical system that combines an 'ultrasound tweezers'-based mechanical stressor and a Förster resonance energy transfer (FRET)-based molecular force biosensor, termed "actinin-sstFRET," to monitor in situ single-cell allostasis in response to transient stimulation in real time. Methods: The ultrasound tweezers utilize 1 Hz, 10-s transient ultrasound pulses to acoustically excite a lipid-encapsulated microbubble, which is bound to the cell membrane, and apply a pico- to nano-Newton range of forces to cells through an RGD-integrin linkage. The actinin-sstFRET molecular sensor, which engages the actin stress fibers in live cells, is used to map real-time actomyosin force dynamics over time. Then, the mechanosensitive behaviors were examined by profiling the dynamics in Ca2+ influx, actomyosin cytoskeleton (CSK) activity, and GTPase RhoA signaling to define a single-cell mechanical allostasis. Results: By subjecting a 1 Hz, 10-s physical stress, single vascular smooth muscle cells (VSMCs) were observed to remodeled themselves in a biphasic mechanical allostatic manner within 30 min that caused them to adjust their contractility and actomyosin activities. The cellular machinery that underscores the vital role of CSK equilibrium in cellular mechanical allostasis, includes Ca2+ influx, remodeling of actomyosin CSK and contraction, and GTPase RhoA signaling. Mechanical allostasis was observed to be compromised in VSMCs from patients with type II diabetes mellitus (T2DM), which could potentiate an allostatic maladaptation. Conclusions: By integrating tools that simultaneously permit localized mechanical perturbation and map actomyosin forces, we revealed distinct cellular mechanical allostasis profiles in our micromechanical system. Our findings of cell mechanical allostasis and maladaptation provide the potential for mechanophenotyping cells to reveal their pathogenic contexts and their biophysical mediators that underlie multi-etiological diseases such as diabetes, hypertension, or aging. [ABSTRACT FROM AUTHOR]

N -Sulfonyl- and N -acylpyrroles were synthesized via olefin ring-closing metathesis of diallylamines and in situ oxidative aromatization in the presence of the ruthenium Grubbs catalyst and a suitable copper catalyst. In the presence of Cu(OTf)2 and CuBr2 , the reaction afforded N -sulfonyl- and N -acylpyrroles, respectively, in one pot. Under an oxygen atmosphere, the reaction went smoothly without the need of hydroperoxide oxidants. This protocol possesses many advantages, such as using a nonhazardous oxidant and readily available starting materials, operating in one pot, and showing a broad substrate scope. [ABSTRACT FROM AUTHOR]

Abstract Wastewater containing heavy metal ions such as lead should be treated for cleanup before discharge to environment. This work reports new nanomaterials of orthohexagonal iron oxide for efficient removal of lead (II), which were doped with cobalt (Co Fe 2 O 3) or Nickel (Ni Fe 2 O 3) ions through a simple method. The structure of adsorbents and adsorption mechanism were investigated by scanning electron microscopy, transmission electron microscopy, energy dispersive spectrometer, Fourier transformed infrared spectroscopy, X-ray photoelectron spectroscopy and so on. The results showed that the concentration of nitrate concentration has a tiny effect on the Pb(II) adsorption and the kinetic adsorption experiments showed that Co Fe 2 O 3 and Ni Fe 2 O 3 took less time to achieve the equilibrium state than Fe 2 O 3 without doping And the isotherm batch experiments showed that Langmuir model matched well with the data of Fe 2 O 3 , Freundlich model fitted well in Co Fe 2 O 3 and Ni Fe 2 O 3 experiments data, indicating that cobalt/nickel doping changes the adsorption mechanism. XPS analysis showed that the hydroxyl at surface played an important role in Pb(II) removal and the hydrogen bond was replaced by metal-oxygen bond. Furthermore, the adsorption capacities of, Co Fe 2 O 3 and Ni Fe 2 O 3 for Pb(II) removal were 136.0 mg/g and 97.5 mg/g respectively, which were superior to pristine Fe 2 O 3 (93.9 mg/g). This study clearly showed that Co Fe 2 O 3 and Ni Fe 2 O 3 are promising candidates for lead ion removal in aqueous solution. Graphical abstract Image Highlights • Ortho-hexagonal iron oxides at nanometer scale have been synthesized through a cost-effective simple method. • The crystal structure of α-Fe 2 O 3 was transformed into γ-Fe 2 O 3 by doping with cobalt or nickel. • The doping with cobalt greatly enhanced the adsorption capacity of the iron oxides. • The adsorption mechanism of lead on the materials was extensively studied. [ABSTRACT FROM AUTHOR]

Adaptive simulations solving the Navier-Stokes equations have been conducted in order to get a better understanding on the detonation initiation and propagation in a stoichiometric H 2 /O 2 /Ar supersonic mixture with boundary layer. The detonation is initiated by a continuous hot jet. When reflecting on the wall, the jet induced bow shock interacts with the boundary layer and forms the shock boundary layer interaction phenomena, while in Euler result the bow shock forms Mach reflection. The investigation shows that the Navier-Stokes simulation result is structurally in better agreement with the experiment compared with that of the inviscid Euler simulation result. The bow shock interacts with the separation shock, forming the shock induced combustion behind the interaction zone. Then the combustion front couples with shock and forms Mach stem induced detonation. The Mach stem induced detonation continues to getting higher and propagating upstream, initiating the main flow. The initiated partial detonation exists with the separation shock induced combustion front, forming an “oblique shock induced combustion-partial detonation” structure in the main flow. The investigation on the influence of free stream Mach number further confirms that the boundary layer has an important influence on detonation initiation. The parametric studies also show that there exists a free stream Mach number range to initiate the partial detonation in supersonic combustible flow successfully. [ABSTRACT FROM AUTHOR]

Abstract: Lead contamination is a threat for the environment and human health due to lead non-degradability and non-detoxification. Therefore, methods for efficient removal of lead from contaminated waters are needed. Here, a novel material has been synthesised by surface functionalization of magnesium-aluminum layered double hydroxide with citrate (citric-LDH) and applied to the efficient removal of lead from aqueous solutions. Effects of ionic strength and temperature on the adsorption have been evaluated. Results show that lead adsorption by citric-LDH can be used for lead pollution cleanup. Adsorption kinetics were simulated using a revised model. Simulation results show that citric-LDH adsorb lead ions through a more efficient and time-dependent pathway, leading to the rapid and efficient removal of lead ions. [ABSTRACT FROM AUTHOR]

In this study, detonation initiation in supersonic premixed flow is experimentally investigated using hot jets with different strength. Two types of shock interaction models, B/S (bow/separated) and S/S (separated/separated), are observed, respectively. In the case with the high-strength hot jet, the ignition of the combustible mixture is triggered by the interaction between jet-induced bow and bottom separated shocks, which results in the generation of a Mach stem further initiating the detonation. Finally, the structure of SSIC (separated shock-induced combustion)/LD (local detonation)/SSIC (separated shock-induced combustion) is observed. For the low-strength hot jet, detonation initiation could not be realized by the interaction between bow and separated shocks, and only the separated shock-induced combustion is observed. The interaction of shock surfaces in the flow field is dominated by the upper separated shock. Finally, a V-shaped SSIC/SSIC structure is generated associated with the forward propagation of separated shocks in the supersonic flow. [ABSTRACT FROM AUTHOR]

RDD involving the central nervous system is rarely reported. To better understand the disease and explore the treatments, we reported this case and review the literature. [ABSTRACT FROM AUTHOR]

Metasurfaces, composed of micro-nano-structured planar materials, offer highly tunable control over incident light and find significant applications in imaging, navigation, and sensing. However, highly efficient polarization devices are scarce for the extended shortwave infrared (ESWIR) range (1.7~2.5 μm). This paper proposes and demonstrates a highly efficient all-dielectric diatomic metasurface composed of single-crystalline Si nanocylinders and nanocubes on SiO2. This metasurface can serve as a nanoscale linear polarizer for generating polarization-angle-controllable linearly polarized light. At the wavelength of 2172 nm, the maximum transmission efficiency, extinction ratio, and linear polarization degree can reach 93.43%, 45.06 dB, and 0.9973, respectively. Moreover, a nonpolarizing beam splitter (NPBS) was designed and deduced theoretically based on this polarizer, which can achieve a splitting angle of ±13.18° and a phase difference of π. This beam splitter can be equivalently represented as an integration of a linear polarizer with controllable polarization angles and an NPBS with one-bit phase modulation. It is envisaged that through further design optimization, the phase tuning range of the metasurface can be expanded, allowing for the extension of the operational wavelength into the mid-wave infrared range, and the splitting angle is adjustable. Moreover, it can be utilized for integrated polarization detectors and be a potential application for optical digital encoding metasurfaces. [ABSTRACT FROM AUTHOR]

This paper presents generalized logic-based methods for intelligent fault diagnosis in power electronic converters based on correlation between faults and basic measurements. Fault recovery is then applied based on this correlation by using necessary signals and quantities from existing measurements. The main purpose of the proposed fault diagnosis methods is for power electronic systems to survive from fault conditions that could occur in various components, to cope with the notion of a smart grid and extend their lifetime. The proposed methods are online, i.e., real-time or near-real-time, and can be applied to any power electronic system. Existing intelligent control of power electronic systems along with various short- and open-circuit faults in major power electronic components are reviewed. Two methods are established to diagnose faults and engage redundancy for fault recovery with one method using combinational logic and another using fuzzy logic. In both methods, two quantities are observed for each of the measured signals: 1) the signal's average value and 2) the signal's RMS value. Total harmonic distortion is also used in some simulations but is not required in experimental implementation. A systematic methodology to reduce the number of measured quantities while maintaining effective diagnosis is introduced. A solar PV microinverter in standalone mode is used as an example testing platform for the proposed methods. A simulation model is experimentally validated and the effect of each fault on different voltage and current measurements are observed, then both methods are tested in simulation and hardware. Results show the ability of both methods to diagnose several faults in the inverter's power stage along with their ability to engage redundancy for fault recovery. [ABSTRACT FROM AUTHOR]

The asymmetric dearomatization and addition reaction of bromomethylnaphthalenes with aldehydes proceeded smoothly in the presence of carbazole-based bisoxazoline CrCl2 complex to give the corresponding enanioenriched hydroxylated dearomatization products. The excellent chemo-, regio-, diastereo- and enantioselecitivity are remarkable. Furthermore, hydrogenation of the product led to highly elaborated compound containing three contiguous stereogenic centers. [ABSTRACT FROM AUTHOR]

Posttraumatic acute diffuse brain swelling (PADBS) is characterized by serious brain bulk enlargement rapidly following trauma and is a major cause of elevated intracranial pressure and thus mortality. The pathogenesis of PADBS is not clearly understood, and the early stage alterations of catecholamine (CA) and adrenocorticotropic hormone (ACTH) levels in PADBS also remain largely unknown. The objective of this study was to investigate CA and ACTH levels in the patients with PADBS in the early stage and discuss the possible roles CA and ACTH in the pathogenesis of PADBS. It is a cross-sectional study. A group of patients with PADBS (n = 10) was compared with a group of patients with severe brain injury (SBI) (n = 33). A control group of healthy adults (n = 25) was also included. Blood samples were obtained to measure levels of epinephrine (EPI), norepinephrine (NE), dopamine (DA), and ACTH as soon as the patients arrived at the neurosurgery department, which was done within 4 h after trauma. Both SBI and PADBS groups of patients had higher levels of EPI, NE, DA, and ACTH than the control group. The PADBS group had significantly higher levels of EPI, NE, and ACTH than the SBI group. CA and ACTH levels are significantly increased in early stage PADBS. These results imply that CA and ACTH may play important roles in the pathogenesis of PADBS. To eliminate the effects of CA and ACTH at the early stage, and thereby protect the hypothalamus and brain stem, might be critical measures for treating patients with PADBS. [ABSTRACT FROM AUTHOR]

In order to investigate the mechanism of detonation combustion in expanding channel filled with supersonic combustible mixtures, the open-source program AMROC was adopted for high-resolution detonation simulations in a stoichiometric H 2 /O 2 /N 2 mixture using a hot jet initiation. For the supersonic combustible mixture under the condition of pressure 6670 Pa and temperature 298 K, the hot jet with a width of 4.0 mm cannot initiate detonation directly in the 5.4° expanding channel. The jet induced bow shock continues rising up towards the incoming flow and finally forms Mach reflection. In the Mach stem, a local detonation is realized. An oblique shock deforms from the Mach stem near the wall and propagates forward with the Mach stem. The triple point between the Mach stem and the bow shock collides up and down, initiating the whole flow. The initiated detonation wave propagates forward at a relative speed of 55.9 m/s and the overdrive degree is 1.059, which indicates that the initiated detonation wave is almost a CJ detonation. The comparison of the reflecting structure between the numerical result and experimental observation indicates that the numerical result can give qualitatively correct conclusions. [ABSTRACT FROM AUTHOR]

Background and purpose Cell cycle phase could affect the cellular uptake of nanoparticles. Based on the fact that ionizing radiation exposure can delay cell cycle progression including inducing G2/M phase arrest, we propose that ionizing radiation exposure is a cell cycle phase-dependent targeting approach for intracellular delivery of nano-agents in tumor cells. Materials and methods We synthesized luminescent gold nanoclusters (AuNCs) using a one-pot green synthetic method. Subsequently, we used the as-prepared AuNCs as both “nano-agents” and fluorescent trafficking probes for our study using human cervical carcinoma HeLa cells. Estimating the cellular uptake of AuNCs and cell cycle analysis were performed following X-rays irradiation and cell synchronization. Results Our work showed that X-rays irradiation could delay the division of HeLa cells and thereby enhance the retention of AuNCs in HeLa cells, which is a reverse strategy compared with other studies on synergistic nano-radiotherapy. Our results demonstrated that the cell cycle synchronization influenced the cellular uptake processes of AuNCs, suggesting that dynamic cell cycle progression could affect the cellular uptake kinetics of AuNCs. Conclusion We consider that the radiation-induced cell division delay might provide a possible mechanism underlying the enhanced effect for the cellular uptake of AuNCs in irradiated HeLa cells. [ABSTRACT FROM AUTHOR]

In this issue of Molecular Cell , Tan et al. (2017) provide novel perspectives into the regulatory role of WHIP-TRIM14-PPP6C signalosome in enhancing RIG-I-mediated viral RNA sensing pathway. [ABSTRACT FROM AUTHOR]

The rising prevalence of arthritogenic alphavirus infections, including chikungunya virus (CHIKV) and Ross River virus (RRV), and the lack of antiviral treatments highlight the potential threat of a global alphavirus pandemic. The immune responses underlying alphavirus virulence remain enigmatic. We found that pentraxin 3 (PTX3) was highly expressed in CHIKV and RRV patients during acute disease. Overt expression of PTX3 in CHIKV patients was associated with increased viral load and disease severity. PTX3-deficient (PTX3-/-) mice acutely infected with RRV exhibited delayed disease progression and rapid recovery through diminished inflammatory responses and viral replication. Furthermore, binding of the N-terminal domain of PTX3 to RRV facilitated viral entry and replication. Thus, our study demonstrates the pivotal role of PTX3 in shaping alphavirus-triggered immunity and disease and provides new insights into alphavirus pathogenesis. [ABSTRACT FROM AUTHOR]

Arthritogenic alphaviral infection begins as a febrile illness and often progresses to joint pain and rheumatic symptoms that are described as polyarthritis. Alphaviral arthritis and classical arthritides share many similar cellular and immune mediators involved in their pathogenesis. Recent in vitro and in vivo evidence suggests that bone loss resulting from increased expression of bone resorption mediators may accompany alphaviral infection. In addition, several longitudinal studies have reported more severe and delayed recovery of alphaviral disease in patients with pre-existing arthritic conditions. This review aims to provide insights into alphavirus-induced bone loss and focuses on aspects of disease exacerbation in patients with underlying arthritis and on possible therapeutic targets. [ABSTRACT FROM AUTHOR]

The available techniques for assessing blood cell functions are limited considering the various types of blood cell and their diverse functions. In the past decade, rapid advances in microengineering have enabled an array of blood cell functional measurements that are difficult or impossible to achieve using conventional bulk platforms. Such miniaturized blood cell assay platforms also provide the attractive capabilities of reducing chemical consumption, cost, and assay time, as well as exciting opportunities for device integration, automation, and assay standardization. This review summarizes these contemporary microengineered tools and discusses their promising potential for constructing accurate in vitro models and rapid clinical diagnosis using minimal amounts of whole-blood samples. [ABSTRACT FROM AUTHOR]

White blood cells (WBCs) constitute about 0.1% of the blood cells, yet they play a critical role in innate and adaptive immune responses against pathogenic infections, allergic conditions, and malignancies and thus contain rich information about the immune status of the body. Rapid isolation of WBCs directly from whole blood is a prerequisite for any integrated immunoassay platform designed for examining WBC phenotypes and functions; however, such functionality is still challenging for blood-on-a-chip systems, as existing microfluidic cell sorting techniques are inadequate for efficiently processing unprocessed whole blood on chip with concurrent high throughput and cell purity. Herein we report a microfluidic chip for continuous-flow isolation and sorting of WBCs from whole blood with high throughput and separation efficiency. The microfluidic cell sorting chip leveraged the crossflow filtration scheme in conjunction with a surface-micromachined poly(dimethylsiloxane) (PDMS) microfiltration membrane (PMM) with high porosity. With a sample throughput of 1 mL h−1, the microfluidic cell sorting chip could recover 27.4 ± 4.9% WBCs with a purity of 93.5 ± 0.5%. By virtue of its separation efficiency, ease of sample recovery, and high throughput enabled by its continuous-flow operation, the microfluidic cell sorting chip holds promise as an upstream component for blood sample preparation and analysis in integrated blood-on-a-chip systems. [ABSTRACT FROM AUTHOR]

ObjectiveInterleukin-6 (IL-6) is a pleiotropic proinflammatory cytokine that plays a key role in the injuries and diseases of the central nervous system (CNS). A voltage-gated Na+ channel (VGSC) is essential for the excitability and electrical properties of the neurons. However, there is still limited information on the role of IL-6 in voltage-gated sodium channels. Our study aimed to investigate the effects of IL-6 on Na+ currents in cultured spinal-cord neurons.MethodsVGSC currents were activated and recorded using whole-cell patch-clamp technique in the cultured rat spinal cord neurons. The effects of IL-6 concentration and exposure duration were examined. To determine whether any change in the number of channels in the plasma membrane can inhibit IL-6 on VGSC currents, we examined the expression of α1A (SCN1α) subunit mRNA level and protein level in the neurons before and after IL-6 induction using real-time polymerase chain reaction.ResultsWe verified that IL-6, through a receptor-mediated mechanism, suppressed Na+ currents in a time- and dose-dependent manner, but did not alter the voltage-dependent activation and inactivation. Gp130 was involved in this inhibition. Furthermore, the spike amplitude was also inhibited by IL-6 in the doses that decreased the Na+ currents.ConclusionVGSC currents are significantly inhibited by IL-6. Our findings reveal that the potential neuroprotection of IL-6 may result from the inhibitory effects on VGSC currents. [ABSTRACT FROM PUBLISHER]

Abstract: Objective: Coronary artery disease (CAD) is a complex disease resulting from a combination of environmental and genetic factors. We hypothesized that polymorphisms in methionine sulfoxide reductase A (MSRA: rs10903323 G/A) and vascular endothelial growth factor A (VEGFA: rs699947 C/A, rs2010963 G/C, and rs3025039 C/T) contribute to CAD susceptibility. Designs and methods: We examined the association between the four polymorphisms and the risk of CAD in a Chinese population of 435 CAD patients and 480 controls. Genotyping was performed using matrix-assisted laser desorption ionization/time-of-flight mass spectrometry (MALDI/TOF-MS). Results: When the MSRA rs10903323 GG homozygous genotype was used as the reference group, the GA and GA/AA genotypes were associated with a significantly increased risk of CAD (GA vs GG: adjusted OR=1.36, 95% CI=1.02–1.82, p =0.038; GA/AA vs GG: adjusted OR=1.33, 95% CI=1.01–1.76, p =0.042). The AA homozygous genotype was not associated with a risk of CAD. In the recessive model, when the MSRA rs10903323 GG/GA genotypes were used as the reference group, the AA homozygous genotype was not associated with a risk of CAD. Logistic regression analyses revealed that the VEGFA rs699947 C/A, VEGFA rs2010963 G/C, and VEGFA rs3025039 C/T polymorphisms were not associated with a risk of CAD. Conclusions: These findings suggest that the functional MSRA rs10903323 G/A polymorphism is associated with CAD development. However, our results allow only a preliminary conclusion, which must be validated with a larger study of a more diverse ethnic population. [Copyright &y& Elsevier]

Out with the metal: Metal‐free hydrogenation of unfunctionalized olefins can be achieved by employing HB(C6F5)2 as the catalyst. The key step in the catalytic reaction is believed to involve a novel borane‐mediated σ‐bond metathesis, which has been investigated both experimentally and theoretically. [ABSTRACT FROM AUTHOR]

Bor statt Metall: Die metallfreie Hydrierung nichtfunktionalisierter Olefine gelingt mit dem Katalysator HB(C6F5)2. Als entscheidender Schritt der Katalyse wird eine neuartige boranvermittelte σ ‐ Bindungsmetathese vorgeschlagen, die experimentell und theoretisch untersucht wird. [ABSTRACT FROM AUTHOR]

Food system is the foundation of human society, thus the sustainable transition of food system is one of the key topics towards global sustainability. Facing the global climate crisis, regional conflict, and pandemic that unseen in a century, it becomes critical to build a sustainable food system in line with the Chinese context for ensuring its grain and food security, national nutrition and health, social justice, ecological balance, market effectiveness, and system resilience. To address these focuses, this study analyzed the main issues and challenges faced by China's current food system, and decoded the relationship between food system and sustainable development goals of the United Nations from supply, demand, and security guarantee mechanism perspectives. Based on these, this study developed a conceptual framework for sustainable food system from life cycle, global, and system perspectives. This study further identified six key dimensions, including security, health, justice, greenness, economy, and resilience, for constructing the strategic framework of China's sustainable food system, and proposed paths ahead for implementation. We hope to provide some system reflections on how to ensure China's food security in the new era and further to contribute to sustainable global food system transition with Chinese wisdom and Chinese solutions. [ABSTRACT FROM AUTHOR]

The aim of this study was to retrospectively evaluate the effectiveness of the Stryker Leibinger neuronavigation system in surgical resection of hemangioblastomas of the posterior fossa. The study included 16 cases of solid hemangioblastoma of posterior cranial fossa treated since we began using Stryker Leibinger neuronavigation system-assisted microneurosurgery in 2003. These cases were compared on the basis of time, blood loss, and complications to 19 similar cases of solid hemangioblastoma that underwent conventional microneurosurgical resection prior to 2003. All patients in the experimental (neuronavigation-assisted) group underwent surgical resection without complications while the control groups' resections all involved blood loss related to the longer operation time. Neuronavigation also resulted in a clear field of surgical vision and clear lesion boundaries, making it easier to remove lesions and reduce accidental injury of adjacent normal structures. The application of navigation technology is very valuable for solid hemangioblastoma operations not only by shortening operative time, thereby significantly reducing operative blood loss, but also by making surgical excision easier, reducing damage to adjacent normal structures, and decreasing surgical complications and mortality. [ABSTRACT FROM AUTHOR]

Abstract: Extending band-limited constructions of orthonormal refinable functions, a special class of periodic functions is used to generate a family of band-limited refinable functions. Characterizations of Riesz bases and frames formed by integer shifts of these refinable functions are obtained. Such families of refinable functions are employed to construct band-limited biorthogonal wavelet bases and biframes with desirable time-frequency localization. [Copyright &y& Elsevier]

In the present study, two piperazine-substituted quinazolin-4(3 H)-one derivatives, namely 2-phenyl-3-(2-(4-phenylpiperazin-1-yl)ethyl)quinazolin-4(3 H)-one (PPQ) and 3-(2-(4-(2-methoxyphenyl)piperazin-1-yl)ethyl)-2-phenylquinazolin-4(3 H)-one (MPPQ), have been designed and investigated as effective corrosion inhibitors for mild steel in HCl, providing a strong basis for the development of new inhibitor platform in the field of corrosion. The corrosion inhibition performance of PPQ and MPPQ has been studied by using weight loss tests, electrochemical techniques, surface analytical techniques, quantum chemical calculations and molecular dynamics (MD) simulations. The experimental results revealed that PPQ and MPPQ are effective corrosion inhibitors for mild steel in 1.0 M HCl solution, and their maximum corrosion inhibition efficiencies at 0.4 mM are 96.6% and 96.1%, respectively. The effects of immersion time and temperature were studied by weight loss tests to assess the stability of the adsorbed film in protecting mild steel surface. Both PPQ and MPPQ behave as mixed-type inhibitors based on potentiodynamic polarization studies, and their adsorption on the mild steel surface follows the Langmuir adsorption isotherm. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) further confirmed the formation of a protective film on the steel surface. Quantum chemical calculations and MD simulations were used to investigate the correlation between the molecular structure of inhibitors and their corrosion inhibition performances, which agree well with the experimental results. The inhibition mechanism has also been discussed in terms of the mixed type of chemical and physical interactions that lead to its adsorption on the steel surface. [Display omitted] [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study aimed to assess the efficacy, safety and tolerability of oral moxifloxacin in patients with respiratory tract infections (RTIs) treated by attending physicians in routine clinical practice in China. METHODS: This was an open-label, prospective, uncontrolled, post-marketing surveillance study that was undertaken between November 2002 and July 2003. Altogether, 855 patients with RTIs were treated with moxifloxacin. Data were collected by 257 physicians throughout China. Symptoms of RTI (fever, cough, purulent sputum, dyspnoea, thoracic pain, nasal obstruction, nasal secretion and headache), together with auscultatory findings, were assessed at baseline and at follow-up visits, and classified as ‘absent’, ‘mild’ or ‘severe’ by the attending physician. RESULTS: Moxifloxacin produced significant improvements in 70.7% of patients after only 3 days of treatment. In 91.7% of patients, symptoms were improved after 5 days of treatment; 76.1% of patients recovered after 7 days and 84.7% recovered after 10 days of treatment. The mean ± SD time until recovery was 5.1 ± 2.6 days. Assessment of treatment efficacy by the physicians was ‘good’ or ‘very good’ for 89.2% of patients. In 87.3% of cases, physicians rated patients’ acceptance of therapy with moxifloxacin as ‘good’ or ‘very good’. The tolerability of moxifloxacin therapy was rated as ‘good’ or ‘very good’ for 88.8% of patients. Very few adverse events (4.1% of patients) were reported with moxifloxacin; most of them involved mild CNS disorders and gastrointestinal disturbances. CONCLUSIONS: Moxifloxacin was shown to be an effective and well tolerated treatment for this group of patients with RTIs and was highly rated by both physicians and patients because of rapid symptom improvement and good tolerability. [ABSTRACT FROM AUTHOR]

Background: Evidence regarding the relationship between serum vitamin C levels and human papillomavirus (HPV) infection is limited. Therefore, this study aimed to investigate whether serum vitamin C levels are independently associated with HPV infection.Methods: Data for this cross-sectional study were obtained from the National Health and Nutrition Examination Survey 2003-2006. A total of 2174 women, 18-59 years of age, were enrolled in this study. The associations between serum vitamin C levels (continuous and categorical forms) and cervicovaginal HPV infection were estimated using weighted logistic regression.Results: The adjusted binary logistic regression showed that serum vitamin C was not associated with the risk of HPV infection after adjusting for age, race, poverty income ratio, alcohol consumption, smoking, body mass index, education, and health condition (odds ratio [OR] 0.998, 95% confidence interval [CI] 0.994-1.001). Serum vitamin C levels were converted from a continuous variable to a categorical variable for the analysis. Compared with the vitamin C deficiency and hypovitaminosis groups, there was a negative correlation between vitamin C and HPV infection when vitamin C was adequate (OR 0.7, 95% CI: 0.52-0.94); however, when the serum vitamin C level was inadequate and saturated, this negative correlation was weaker or nonexistent (OR 0.76, 95% CI 0.56-1.03 and OR 0.76, 95% CI 0.55-1.04, respectively). A nonlinear relationship was detected between vitamin C level and HPV infection. Furthermore, we performed subgroup analysis of different models and found that serum vitamin C concentration was negatively associated with HPV infection in women ≥ 25 years of age; however, in women < 25 years of age, serum vitamin C levels were not associated with HPV infection.Conclusion: The results from this United States nationally representative sample supported the hypothesis that there was a U-shaped relationship between serum vitamin C levels and HPV infection. Future studies are warranted to assess the association between vitamin C and HPV persistence and clarify the underlying mechanisms of these associations. [ABSTRACT FROM AUTHOR]

Gypsum rock is highly sensitive to a water environment due to its unique physical and chemical properties, such as high solubility. After wetting, the internal microstructure of gypsum rock is damaged, and the mechanical properties deteriorate accordingly, leading to serious engineering problems for gypsum-bearing geotechnical structures. Therefore, it is particularly necessary to investigate the mechanical deterioration behavior of gypsum rock after wetting. In this paper, the mechanical behavior of gypsum rocks with different water contents were studied. The relationship between the rock water content and the water immersion time was established through the water content test. The scanning electron microscope (SEM) images of the gypsum rock after the water immersion showed that the internal microstructure of the gypsum rock became looser and more complex as the immersion time increased. The fractal dimensions of the SEM images were calculated to quantify the degree of damage to the gypsum rocks after wetting. These images showed that the degree of damage increased with the increasing immersion time, but the increase rate tended to be slow. The relationship between the rock water content and the mechanical responses of gypsum rock were established by triaxial compression tests, and the concomitant acoustic emission (AE) characteristics in the loading processes showed that the immersion time had a positive correlation with the AE frequency and a negative correlation with the AE cumulative count. Based on the AE characteristics, a damage constitutive model of gypsum rock as a function of immersion time was developed and this can reproduce the mechanical responses of gypsum rock after wetting. [ABSTRACT FROM AUTHOR]