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Hollow mesoporous Co–N–C@mSiO2 catalysts derived from ZIF-67 via the encapsulation–pyrolysis strategy exhibit excellent performance and good stability for furfural hydrogenation.

Introduction: Transient infantile hypertriglyceridemia (HTGTI) is a rare autosomal recessive disease. At present, only 20 cases of HTGTI have been reported worldwide. Hence, it is necessary to further assess the phenotypic and genetic variation spectra of HTGTI. Case Presentation: A 10-month-old male infant was diagnosed with hypertriglyceridemia, hepatomegaly, liver injury, fasting hypoglycemia, and insulin resistance. Trio-whole exome sequencing (trio-WES) was performed on the patient and his parents. Bioinformatics software was used to analyze the suspected genes and potential pathogenicity of the resulting mutant proteins. The results of trio-WES demonstrated that the patient was homozygous for a novel mutation in the GPD1 gene (NM_005276.3; c.805C>T/p.Arg269Trp), whereas his parents were heterozygous for the same mutation. Bioinformatics prediction results demonstrated that the mutation might affect the protein function, and crystal simulation results showed that the mutation might affect the protein-binding ability of the enzyme. Conclusion: Our results indicated that the novel homozygous mutation in GPD1 could be the pathogenic factor in the patient. Our report highlights the value of genome sequencing in the diagnosis of infant liver disease with low phenotypic heterogeneity.

In the era of big data, the Internet is enmeshed in people’s lives and brings conveniences to their production and lives. The analysis of user preferences and behavioral predictions of user data can provide references for optimizing information structure and improving service accuracy. According to the present research, user’s behavior on social networking sites has a great correlation with their personality, and the five characteristics of the OCEAN (Openness, Conscientiousness, Extraversion, Agreeableness, and Neuroticism) personality model can cover all aspects of a user’s personality. It is important in identifying a user’s OCEAN personality model to analyze their digital footprints left on social networking sites and to extract the rules of users’ behavior, and then to make predictions about user behavior. In this paper, the Latent Dirichlet Allocation (LDA) topic model is first used to extract the user’s text features. Second, the extracted features are used as sample input for a BP neural network. The results of the user’s OCEAN personality model obtained by a questionnaire are used as sample output for a BP neural network. Finally, the neural network is trained. A mapping model between the probability of the user’s text topic and their OCEAN personality model is established to predict the latter. The results show that the present approach improves the efficiency and accuracy of such a prediction.

The structure and size of bimetallic catalysts play a crucial role in many important chemical transformations. Controlled synthesis of bimetallic nanoparticles avoiding overgrowth and aggregation can be achieved by surfactants, which are always detrimental to catalytic performances and understanding of structure-property relationship. Preparation of surface-clean bimetallic catalysts with uniform size and well-defined structure is still challenging. Herein the Au-Pt bimetallic nanoparticles immobilized on SBA-15 were prepared by facile adsorption-reduction method. Characterizations showed that Au-Pt bimetallic nanoparticles were evenly confined within the mesopores of SBA-15, possessing the uniform size of 6.0 nm and existing in the form of alloy structure. For the first time the Au-Pt bimetallic nanoalloys with Au-to-Pt molar ratio of 5:1 (Au5Pt1@SBA-15) exhibited a lot higher activity than monometallic Au@SBA-15 and Pt@SBA-15 catalysts with excellent selectivity towards 1,2,3,4-tetrahydroquinoline for chemoselective hydrogenation of quinoline in water under very mild conditions. It was superior to other heterogeneous catalysts reported to date. The observed properties were related to the synergic effect between Au and Pt. The Pt sites of high electron density originated from the electron transfer between Au and Pt enhanced the ability of H2 dissociation and then provided a new and main approach to H2 splitting, while the Au sites accounted for the adsorption and activation of quinoline. This precise synthetic strategy will be very helpful to explore surface-clean gold-based bimetallic catalysts with high performance for selective hydrogenations.

In the principle of lens imaging, when we project a three-dimensional object onto a photosensitive element through a convex lens, the point intersecting the focal plane can show a clear image of the photosensitive element, and the object point far away from the focal plane presents a fuzzy image point. The imaging position is considered to be clear within the limited size of the front and back of the focal plane. Otherwise, the image is considered to be fuzzy. In microscopic scenes, an electron microscope is usually used as the shooting equipment, which can basically eliminate the factors of defocus between the lens and the object. Most of the blur is caused by the shallow depth of field of the microscope, which makes the image defocused. Based on this, this paper analyzes the causes of defocusing in a video microscope and finds out that the shallow depth of field is the main reason, so we choose the corresponding deblurring method: the multi-focus image fusion method. We proposed a new multi-focus image fusion method based on sparse representation (DWT-SR). The operation burden is reduced by decomposing multiple frequency bands, and multi-channel operation is carried out by GPU parallel operation. The running time of the algorithm is further reduced. The results indicate that the DWT-SR algorithm introduced in this paper is higher in contrast and has much more details. It also solves the problem that dictionary training sparse approximation takes a long time.

Engineering the interface plays a vital role in tuning the catalytic properties of supported metal nanocatalysts. Herein the 0.73%Au-4.13%FeOx@SBA-15 catalyst was constructed with SBA-15 as support and FeOx as modifier by interface engineering. It exhibited better catalytic activity than 0.71%Au/SiO2, 0.69%Au@SBA-15 and 0.71%Au/bulk-FeOx under identical conditions as well as higher selectivity towards cinnamyl alcohol for selective hydrogenation of cinnamaldehyde. It was found that the introduction of FeOx fabricated the interfacial area between Au and FeOx for H2 dissociation and consequently led to higher catalytic activity of 0.73%Au-4.13%FeOx@SBA-15. Meanwhile, both the channel of the SBA-15 support and the presence of small-sized FeOx promoted the selectivity for hydrogenation of C = O bond. It demonstrated for the first time that the interface engineering provided an efficient and facile avenue to design Au catalysts of excellent performances for selective hydrogenations.

Palladium nanoparticles, which were prepared by modified hyperbranched polyglycerol (mHPG) as stabilizers, can be dispersed well in nonpolar organic solvents and form highly stable nanofluids. The influences of three mHPG products modified with cyclohexanethiol (CSHPG), dodecanethiol (DSHPG), and octadecanethiol (OSHPG) on the preparation and stability of the palladium nanoparticles were investigated. The stability and thermal conductivity enhancement of the hydrocarbon-based nanofluids with Pd@mHPG (Pd@CSHPG, Pd@DSHPG, and Pd@OSHPG) compared to the corresponding base fluid were investigated at different temperatures. The average diameters of nanoparticles stabilized by CSHPG, DSHPG, and OSHPG are within 2.7-3.6 nm. The palladium nanoparticles could be dispersed well in the nonpolar base fluid such as decalin. The nanofluids with Pd@DSHPG and Pd@OSHPG could remain stable for up to 330 days at room temperature. The nanofluid with Pd@DSHPG or Pd@OSHPG could be stable for more than 24 h at 110 °C. The thermal conductivity of the nanofluids improved with increasing temperature and the mass fraction of nanoparticles compared to the corresponding base fluid. The long alkyl chain-modified HPG can give better protection for nanoparticles from agglomeration and assist metal nanoparticles in enhancing the thermal conductivity of nanofluids.

Measurements on densities, viscosities, and refractive indices at atmospheric pressure for binary mixtures of 1,3-dimethyladamantane (1,3-DMA), 1,3,5-trimethyladamantane (1,3,5-TMA), and 1-ethylada...

Au nanoparticles confined within the mesopores of the modified SBA-15 were obtained through adsorption-reduction method and firstly employed as chemoselective catalyst for quinoline hydrogenation. The effects of Au loadings, calcination temperature as well as structure of support on catalytic performances of Au catalysts were explored. The as-obtained 1.2%Au@SBA-15-500 catalyst exhibited high activity, excellent selectivity towards 1,2,3,4-tetrahydroquinoline and extraordinary sintering-resistant property as high as 800 °C, which is sharp contrast to the 1.3%Au/SiO2-500 catalyst. It also showed good recyclability and versatility for quinoline derivatives. The observed properties were assigned to small-sized Au nanoparticles and mesopores of SBA-15. Our work provides a facile and promising approach to construct metal nanocatalysts with high catalytic performance by the use of mesoporous materials.

Electrochemical sensors benefit from low cost and fast detection speeds, which makes them suitable for routine analysis of small biological molecules such as dopamine (DA). DA is a neurotransmitter that plays an important physiological role and can be used as a marker for conditions such as depressive disorder and Parkinson’s disease. In this communication, electrodes modified with self-assembled gold nanoparticles (SA-AuNPs) were used as electrochemical sensors for the detection of DA with the aim of achieving better signal stability among the same batch of electrodes. High signal reproducibility among the SA-AuNP-modified electrodes was obtained due to the more orderly packing of AuNPs leading to relatively consistent electrochemical resistance and homogeneous mass transport.

The unique electronic structure and crystal structure driven by external pressure in transition metal tellurides (TMTs) can host unconventional quantum states. Here, the discovery of pressure‐induced phase transition at ≈2 GPa, and dome‐shaped superconducting phase emerged in van der Waals layered NbIrTe4 is reported. The highest critical temperature (T c) is ≈5.8 K at pressure of ≈16 GPa, where the interlayered Te–Te covalent bonds form simultaneously derived from the synchrotron diffraction data, indicating the hosting structure of superconducting evolved from low‐pressure two‐dimensional (2D) phase to three‐dimensional (3D) structure with pressure higher than 30 GPa. Strikingly, the authors have found an anisotropic transport in the vicinity of the superconducting state, suggesting the emergence of a “stripe”‐like phase. The dome‐shaped superconducting phase and anisotropic transport are possibly due to the spatial modulation of interlayer Josephson coupling ., The correlation of novel electrical properties and structural evolutions in van der Waals layered material is revealed by performing special high‐pressure measurements. A superconducting model is proposed to explain the emergence of “stripe”‐like phases and the evolution of critical temperature. Spatial modulation of interlayer Josephson coupling furthers the understanding of the complex relationships between structure, anisotropy, and superconductivity.

The mechanical properties of copper (Cu) nanowires (NWs) wrapped by carbon nanotube (CNT) under compression are studied by molecular dynamics simulations. By constructing a new structural model, which contains a Cu NW and a CNT that is denoted as CNT@Cu, the mechanical properties, deformation process and structural transformation are investigated in terms of stress–strain relationship, number of stacking faults (SFs) and dislocations, average bond length and atomic configurations. Results show that stress–strain exhibits two nonlinear elastic contraction stages and two intervening stages of inelastic deformation. The stress of Cu NW is almost not affected by the generation and migration activities of SFs but strongly depends on the increasing ratio of SFs due to the supporting of CNT. The inelastic plastic deformation is initiated by nucleation of partial dislocations on the {110} surface and then propagates to interior along the {111} close-packed planes. Wrapped by CNT, a unique structural transformation of compressed Cu NW is found, which is from /{111} to /{100} through the annihilation of {111} SFs planes and formation of {100} SFs planes along the [100] crystallographic orientations. The /{100}-structured wire would undergo nonlinear elastic contraction until to a certain large strain, and then bend near the middle part before NW fractures eventually at a very high stain. What’s more, the /{100}-structured Cu NW possess high reversibility under unloading and an interestingly structural reverse transformation from /{100} to /{111} structure is observed prior to the fracture of NW at a high strain for the CNT@Cu model due the support of CNT. The ultimate compressive elastic strength of {100} (UCES-{100}) and ultimate elastic stain will decrease as the temperature increases from 10 to 500 K. The UCES of pristine (UCES-pristine) and UCSE-{100} decrease as diameter decreases.

In this work, we systematically studied the deposition, characterization, and crystal structure modeling of ScAlN thin film. Measurements of the piezoelectric device’s relevant material properties, such as crystal structure, crystallographic orientation, and piezoelectric response, were performed to characterize the Sc0.29Al0.71N thin film grown using pulsed DC magnetron sputtering. Crystal structure modeling of the ScAlN thin film is proposed and validated, and the structure–property relations are discussed. The investigation results indicated that the sputtered thin film using seed layer technique had a good crystalline quality and a clear grain boundary. In addition, the effective piezoelectric coefficient d33 was up to 12.6 pC/N, and there was no wurtzite-to-rocksalt phase transition under high pressure. These good features demonstrated that the sputtered ScAlN is promising for application in high-coupling piezoelectric devices with high-pressure stability.

The currently reported adsorbents for wastewater purification generally have only limited adsorption capacity towards a single type of pollutant; few of them can simultaneously remove multiple types of pollutants from cocontaminated water with high efficiency. In this work, a kind of β-Cyclodextrin based polymeric adsorbent (PCD-VI) with an expanded “pocket” structure was created, and it exhibited excellent adsorption capacities for different kinds of pollutants, cationic rhodamine B (RB), anionic Congo red (CR) and cadmium ion (Cd(II)) in a mono-component solution. Since the “pocket effect” (composed of cavity inclusion and π-π interactions), electrostatic attraction and coordination were the dominant mechanisms for RB, CR and Cd(II) adsorption, respectively, competitive adsorption was effectively avoided in the simultaneous adsorption process. RB and Cd(II) exhibited a synergistic effect in the RB-Cd(II) binary solution; the coexisting Cd(II) showed a negligible effect on CR adsorption at lower CR concentrations (≤400 mg L−1), while the removal of Cd(II) was prominently promoted by the coexisting CR in the CR-Cd(II) binary system. More importantly, RB and Cd(II) could be recovered separately, and PCD-VI could be recycled without a serious decline in performance even after five sequential adsorption-desorption cycles in the RB-Cd(II) binary system. Our studies suggest promising strategies for fabrication and application of advanced adsorption materials in water pollution remediation.

After synthesized with a solvothermal process, LiFePO4 nanoparticles have been further modified with reduced graphene oxide (rGO) and Ag nanoparticles via a facile heat treatment route. The as-prepared LiFePO4@rGO/Ag exhibits enhanced electrochemical performance in storing Li ions with more than 60% increase in discharge specific capacity compared with pristine LiFePO4 at C/10. The discharge specific capacity of the as-prepared cathode materials reaches to 130 mAhg−1 at high rate of 5 C, which is about 4 times higher than that of pristine LiFePO4. The highly enhanced electrochemical properties of the cathode materials can be attributed to the synergetic effect of rGO nanosheets and Ag nanoparticles, which can build up conductive networks to form 3D nanocomposites together with LiFePO4.

Relaxor ferroelectric crystals of lead magnesium niobate–lead titanate (PMN-xPT) have attracted great attention due to their extraordinary dielectric, piezoelectric, and electromechanical properties. PMN-xPT shows different relaxor behavior and structural phase transitions in a wide temperature and chemical component range. Here, we studied spectroscopy and ferroelectricity of PMN-0.28PT under high pressure. The appearance of a new Raman band and the sudden redshift of UV-vis absorption edge imply a structural phase transition at about 8 GPa. More importantly, the ferroelectricity of the sample is suppressed above a pressure of 5 GPa, and there is no ferroelectricity under further compression. We suggest that the disappearance of ferroelectricity may be related to the polar nanoregions being suppressed by pressure. Our observations of ferroelectricity disappearance above 5 GPa indicate the B-site cation rearrangement in the several nanometers region.

The pyroelectric and piezoelectric properties of 4 at% Mn-doped Bi4Ti2.9W0.1O12 (BiTW-Mn) Aurivillius ceramic were investigated and compared to Bi4Ti2.9W0.1O12 (BiTW) counterpart, which were fabricated using a conventional solid state reaction method. High resistivities of 4.9 × 1012 and 2.5 × 1011 Ω cm at 100 °C were obtained in the W-doped and W/Mn-codoped BiT ceramics, respectively. They showed similar activation energies and ionic-p-type mixed conduction mechanisms. Higher pyroelectric coefficients of 57.1 μC/m2K and piezoelectric coefficients of 21 pC/N, as well as much lower dielectric loss of 0.003 were achieved in W/Mn-codoped ceramics. These property changes were mainly induced by M n Ti − V o defect dipoles. The effect of acceptor doping was evidenced by an internal bias field, shown by a horizontal offset in the polarization-field behavior. The improved properties together with high thermal stability indicate that BiTW-Mn may be a promising candidate for pyroelectric and piezoelectric devices at elevated temperatures.

Background: Heart failure (HF) is the end stage of ischemic cardiovascular diseases; nonetheless, safe and effective therapeutic agents for HF are still lacking, and their discovery remains challenging. Our previous studies demonstrated that Shen-Yuan-Dan Capsule (SYDC), a hospital preparation of traditional Chinese herbal, effectively protected ischemic injury in cardiovascular diseases. However, its therapeutic effects and possible mechanisms on HF remain unclear.Methods: A zebrafish HF model treated with verapamil was developed to assess the therapeutic effect of SYDC on HF zebrafish. Zebrafish were administered with SYDC and digoxin (positive control) by direct soaking. After drug treatment, zebrafish were randomly assigned to the visual observation and image acquisition using a Zebralab Blood Flow System. The reactive oxygen species (ROS), MDA, and SOD levels were determined by fluorescence signal detection, TBA, and WST-8 methods. RT-PCR determined the mRNA expressions of Caspase-3, Caspase-1, Bcl-2, Bax, IL-1β, NF-κB, and TNF-α.Results: SYDC significantly inhibited the levels of heart dilatation and venous congestion and markedly increased the levels of cardiac output, blood flow dynamics, and heart rates in HF zebrafish (p < 0.05, p < 0.01, and p < 0.001). Moreover, SYDC also significantly decreased the levels of MDA and ROS and increased the level of SOD in HF zebrafish. The RT-PCR results revealed that SYDC decreased the expression of Caspase-1, Caspase-3, Bax, IL-1β, NF-κB, and TNF-α but increased the expression of Bcl-2 in HF zebrafish (p < 0.05, p < 0.01, and p < 0.001).Conclusions: SYDC improved the heart function in verapamil-induced HF zebrafish and alleviated inflammation and apoptosis by inhibiting the ROS-mediated NF-κB pathway.

Additional file 1. Spectroscopic investigation of ZnO nanostructures, morphological and crystal structural investigation of ZnO nanostructures to investigate the growth mechanism, the basis for quantitative analysis of MO in the photodegradation, and the stability of the ZnO photocatalyst.

Background and aims The phenotype switching of vascular smooth muscle cells (VSMCs) plays a key role during development and progression of vascular remodeling diseases. Recent studies show that GLP-1 can inhibit intima thickening to delay the progression of atherosclerotic plaques. The purpose of this study was to investigate the role of Exendin-4, a GLP-1 receptor agonist, in VSMCs phenotype switching and the related mechanisms. Methods Immunohistochemistry and Western blot were used to detect the effect of Exendin-4 on expression of markers of contractile VSMCs. Phalloidin staining was performed to observe the effect of Exendin-4 on morphology of VSMCs. Results Exendin-4 significantly increased the protein levels of contractile VSMCs markers like Calponin and SM22α. After treatment of Exendin-4, VSMCs showed more typical characteristic spindle shape. In addition, Exendin-4 significantly upregulated the phosphorylation of AMPK as well as the protein levels of Sirtuin1 (SIRT1) and FOXO3a in VSMCs. After inhibiting AMPK activity with compound C and SIRT1 activity with EX527, and knocking down FOXO3a expression through RNAi technique, Exendin-4 increased the protein levels of Calponin and SM22α and promoted the redifferentiation of VSMCs mainly through AMPK/SIRT1/FOXO3a signaling pathways. Conclusions Exendin-4 can regulate the phenotype switching of VSMCs and promote redifferentiation of VSMCs through AMPK/SIRT1/FOXO3a signaling pathways.

Background Atherosclerosis is a progressive chronic disease characterised by aberrant lipid metabolism and a maladaptive inflammatory response. As atherosclerosis-driven cardiovascular disease remains the major cause of morbidity and mortality worldwide, more effective clinical therapies are urgently needed. Traditional Chinese Medicine (TCM) has demonstrated efficacy against atherosclerosis, with Qing-Xue-Xiao-Zhi formula (QXXZF) having been approved for clinical treatment of patients with atherosclerosis. However, the mechanisms underlying the anti-atherosclerotic activity of QXXZF remain unknown. Purpose To investigate the anti-atherosclerotic effect of QXXZF and reveal its mechanisms using preclinical models. Methods In vivo, apolipoprotein E-deficient (ApoE−/−) mice were fed a high-fat and high-choline diet (HHD) to induce atherosclerosis. Serum metabolomic profiling was used to identify the concentration of trimethylamine N-oxide (TMAO) in mice. In vitro, RAW264.7 macrophages and bone marrow-derived macrophages (BMDMs) from WT and TLR4−/− C57BL/6 mice were used to explore the effects of QXXZF on macrophages. After confirming the therapeutic effects of QXXZF, mass spectrometry and network pharmacology analyses were used to predict and investigate the main components and the anti-atherogenic mechanisms of QXXZF in the context of atherosclerosis. Results Our results showed QXXZF significantly suppressed the development of atherosclerosis, as evidenced by the decreased atherosclerotic plaques in the aorta and aortic root, reduced plasma lipid levels and decreased serum TMAO content in HHD-fed ApoE−/− mice. Meanwhile, QXXZF effectively reduced foam cell formation in oxidized low-density lipoprotein (ox-LDL) and TMAO-stimulated RAW264.7 macrophages and BMDMs. Moreover, QXXZF facilitated reverse cholesterol transport (RCT) in macrophages by upregulating the expression of cholesterol efflux-related genes PPARγ/LXRα/ABCA1/ABCG1. Mechanistic studies revealed that QXXZF influenced cholesterol metabolism by inhibiting the TLR4-mediated nuclear factor kappa B (NF-κB) axis. Importantly, TLR4 knockout abolished the influence of QXXZF on macrophages. Conclusion QXXZF promotes lipid efflux and inhibits macrophage-mediated inflammation, producing a therapeutic effect against atherosclerosis. Our study provides new insight into the mechanism of QXXZF against atherosclerosis.

Highly dispersed silver nanofluids were prepared using cationic gemini surfactants (n-6-n) as stabilizers in aqueous solution. The influences of alkyl chain length in the structure of cationic gemini surfactants on the preparation and stability of the silver nanofluids are presented. The thermal conductivity enhancement of the silver nanofluids was determined by means of the point heat source method. The effects of polar solvents and temperatures on the stability of the silver nanofluids were investigated. The size of the silver nanoparticles is uniform, and their average diameter is about 10–20 nm. The silver nanoparticles could be transferred from an aqueous phase into a dichloromethane or chloroform phase and still be dispersed well. The stability of silver nanoparticles can be ordered as G16-6-16–Ag > G14-6-14–Ag > G12-6-12–Ag.