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• The antibacterial imidazolium ionic liquid was specially designed and synthesized for hydrolyzed ring-opening polymerization of ε -caprolactam. • An intrinsically antibacterial polyamide 6 (PA6-IL) was developed for functional fiber materials. • The modified PA6-IL films and nanofibrous membrane possessed excellent antibacterial activity and durability. • The antibacterial activity and durability of PA6-IL could maintain even if it was melt-spun to be microfibers under high temperature. • The antibacterial PA6 can be widely applied in textile and biomedical fields. The antibacterial polyamide 6 (PA6) material has attracted great research interest due to its wide application in food packaging, biomedical fields, functional textiles, and other fields. However, it is still a challenge to prepare intrinsically antibacterial PA6 with highly efficient and durably antibacterial activity via polymerization. Herein, the antibacterial imidazolium ionic liquid of 3-carboxymethyl-1-decyl imidazole chloride was designed and synthesized for adapting the polymerization and processing temperature of PA6. Then antibacterial PA6 (PA6-IL) was synthesized through hydrolyzed ring-opening copolymerization with imidazolium at the end of the backbones. Compared to physical blending or post-modification methods, antibacterial agents as end-capping reagents of polymer backbones endowed PA6 with intrinsic antibacterial activity. As expected, the obtained PA6-IL exhibited not just comparable physicochemical and mechanical properties to conventional PA6 but excellent antibacterial activity of low antibacterial time to 60 min and durability for 28 days. Additionally, the corresponding electrospun PA6-IL nanofibrous membranes showed homogenous morphology and remarkable hydrophilicity of 7.7° as well as the high-efficient antibacterial activity. Melt-spun PA6-IL microfibers revealed a smooth surface as well as enhanced tensile strength and increased breaking elongation compared to those of conventional PA6. The PA6-IL microfibers also behaved with excellent antibacterial efficiency and durability. Accordingly, this work provides a feasible and straightforward strategy to prepare durably and intrinsically antibacterial PA6 materials especially PA6 fibers, which can be widely applied in the textiles field. [Display omitted] [ABSTRACT FROM AUTHOR]

Constructing a Z-scheme heterostructure on a metal–organic framework (MOF) composite with an explicit charge transfer mechanism at the interface is considered to be an effective strategy for improving the photocatalytic performance of MOFs. Herein, an internal electric field (IEF)-induced Z-scheme heterostructure on the ZnIn2S4@NH2-MIL-125 composite is designed and fabricated by a facile electrostatic self-assembly process. Systematic investigations reveal that close interfacial contact and difference in work function between NH2-MIL-125 and ZnIn2S4enable the formation of the IEF, which drives the Z-scheme charge transfer as revealed by the in situ irradiated X-ray photoelectron spectroscopy (ISI-XPS), photoirradiated Kelvin probe force microscope (KPFM) measurement, electron paramagnetic resonance (EPR) radical trapping experiment, as well as density functional theory (DFT) calculation; meanwhile, directions of the interfacial IEFs are determined. Benefiting from the unique merit of IEF-induced Z-scheme charge transfer, the optimized ZnIn2S4@NH2-MIL-125 composite exhibits significantly enhanced photocatalytic activity for the photoreduction of 4-nitroaniline (4-NA) to p-phenylenediamine (PPD) under visible light irradiation. This work not only provides in-depth insights for charge transfer in the IEF-induced Z scheme heterostructure but also affords useful inspirations on designing the Z-scheme MOF composite to boost the photocatalytic performance.

Chiral conjugated polymers with controlled mesoscopic helicity are gaining attention for enantioseparation and asymmetric catalysis. However, achieving on-demand chirality and processability remain challenging. Herein, we exploit supramolecular coordination polymers formed by Mn2+and chiral phenylglycine derivatives (L-/D-16PhgCOOH) as templates, using m-phenylenediamine as the monomer to synthesize chiral poly(m-phenylenediamine) (PMPD). In the Mn2+-templated system, the PMPD’s handedness is opposite to the molecular chirality of L-/D-16PhgCOOH, while in the Mn2+-free system, the PMPD handedness aligns with that of the template molecule. This method allows for helicity switching of chiral polymers within a single chirality template system. The introduction of Mn2+is demonstrated to disrupt and reconstitute the supramolecular interactions in the co-assembly, influencing subsequent supramolecular stacking patterns. Carbonizing the resulting PMPDs directly produces chiroptical active nitrogen-doped carbonaceous nanomaterials that inherit the original helicity. Moreover, incorporating F-127 into the polymerization system enhances the aspect ratio of PMPDs, facilitating their delicate processing into chiral self-supporting two-dimensional films and three-dimensional foams. With abundant Lewis basic sites, these chiral polymers offer versatile platforms for novel chiral host-guest interactions.

The interaction between terbium-doped arginine functionalized hydroxyapatite nanoparticles (Arg@HAPTbNPs) and cells, and the hindered endocytosis mechanisms of human umbilical vein endothelial cells (HUVECs) were studied by observing the cell uptake of Arg@HAPTbNPs with laser scanning confocal microscopy. Average fluorescence intensity of cells after uptaking different concentrations of NPs was determined by flow cytometer. The results indicate that internalized Arg@HAPTbNPs mainly exist in the cytoplasm of HUVECs, and most of them distribute around the cell nuclei. The entrapment of Arg@HAPTbNPs shows time-dependent and concentration- dependent manners with optimal time of 4 h and concentration of 50 mg/L. Arginine modification significantly improves the uptake efficiency of HAPTbNPs. The entry of Arg@HAPTbNPs into HUVECs is mainly through concave protein-mediated endocytosis, an energy-dependent active transport process.

In the modern wireless communication system, the manipulation for polarization of electromagnetic wave plays a important role in improving the capacity and reliability of communication. In this paper, a multifunctional polarization converter (MFPC) based on the multilayer reconfigurable metasurface is proposed, which can assist the source antenna to transmit and receive multiple polarization signals. The MFPC consists of a grating which can filter out the undesired polarization and four layers of metasurfaces incorporated with PIN diodes. The functions of the MFPC include LTC and LTL polarization conversions, co-polarization transmission and reflection for arbitrary polarization. By changing the states of PIN diodes, the functions of MFPC can be dynamically switched. Loaded on the aperture of source antenna, the proposed MFPC can serve as a transmissive array with multiple polarization channels, and can also provide EM protection for source antenna by reflecting the incoming interference waves. Cascading of the metasurfaces produces Fabry-Perot resonance in the MFPC, and it contributes to the realization of LTC and LTL polarization conversions. To verify the performance of the proposed MFPC, the prototype is fabricated and tested. The measured results show that the fractional bandwidths of four functions are all higher than 31.9% with transmission or reflection coefficients higher than −2 dB. The frequency band of each function is mainly concentrated in S-band. The measured data are in agreement with the simulated results.

Iron is important for life, and iron deficiency impairs development, but whether the iron level regulates neural differentiation remains elusive. In this study, with iron-regulatory proteins (IRPs) knockout embryonic stem cells (ESCs) that showed severe iron deficiency, we found that the Pax6- and Sox2-positive neuronal precursor cells and Tuj1 fibers in IRP1−/−IRP2−/−ESCs were significantly decreased after inducing neural differentiation. Consistently, in vivostudy showed that the knockdown of IRP1in IRP2−/−fetal mice remarkably affected the differentiation of neuronal precursors and the migration of neurons. These findings suggest that low intracellular iron status significantly inhibits neurodifferentiation. When supplementing IRP1−/−IRP2−/−ESCs with iron, these ESCs could differentiate normally. Further investigations revealed that the underlying mechanism was associated with an increase in reactive oxygen species (ROS) production caused by the substantially low level of iron and the down-regulation of iron-sulfur cluster protein ISCU, which, in turn, affected the proliferation and differentiation of stem cells. Thus, the appropriate amount of iron is crucial for maintaining normal neural differentiation that is termed ferrodifferentiation.

The global emergency caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic can only be solved with effective and widespread preventive and therapeutic strategies, and both are still insufficient. Here, we describe an ultrathin two-dimensional CuInP2S6(CIPS) nanosheet as a new agent against SARS-CoV-2 infection. CIPS exhibits an extremely high and selective binding capacity (dissociation constant (KD) < 1 pM) for the receptor binding domain of the spike protein of wild-type SARS-CoV-2 and its variants of concern, including Delta and Omicron, inhibiting virus entry and infection in angiotensin converting enzyme 2 (ACE2)-bearing cells, human airway epithelial organoids and human ACE2-transgenic mice. On association with CIPS, the virus is quickly phagocytosed and eliminated by macrophages, suggesting that CIPS could be successfully used to capture and facilitate virus elimination by the host. Thus, we propose CIPS as a promising nanodrug for future safe and effective anti-SARS-CoV-2 therapy, and as a decontamination agent and surface-coating material to reduce SARS-CoV-2 infectivity.

Xujiahui (XJH) station in downtown Shanghai holds the longest continuous daily temperature series in China, which is unique for assessing modern climate change and impacts but must be homogenised. The present work established a set of homogenised monthly and daily surface air temperature (SAT) series during 1873–2019 at XJH. Two major inhomogeneous break points (around 1954 and 1993) were identified in the original SAT series, which had been overlooked in previous works. The inhomogeneous biases were adjusted via the inter-station deviation analysis. The adjusted SAT series shows a warming trend of 1.9 °C per century compared with 1.7 °C per century in the original series. The multi-decadal variations of quasi-32-year and quasi-64-year periods are weaker in the adjusted series than in the original series, suggesting overestimated multi-decadal variability in the original data due to inhomogeneous biases. Relative to the early period 1873–1900, the recent decade (the 2010s) is warmer by 2.2 °C. Urbanisation has been responsible for approximately 19.3% of the rapid warming since the 1980s. The high and low SAT extremes exhibit significant warming, especially after the 1970s. The trend in the low SAT extremes in the adjusted series is substantially larger than that in the original series, implying that previous studies might underestimate the warming in cold extremes.

AbstractAs an emerging intelligent construction technique, three-dimensional (3D) printing technology can improve the utilization rate of building materials, reduce labor costs and shorten the construction period. However, in traditional 3D printing, large-size 3D print machines, restricted print sizes of structural components and unstable printing quality limit its application in construction engineering. This paper proposes a mobile 3D printing technique for construction engineering. In this technique, a mobile 3D printing construction robot (M3DPC-Rob) is developed that takes advantage of a movable platform and flexible mechanical arm to cover the printing range of ordinary residential buildings. In order to locate the robot accurately in outdoor environments, an outdoor positioning and navigation method based on reflective columns is proposed. Furthermore, a quality control process is developed and modified to improve the quality of the printed line width. The results of a case study reveal that the outdoor navigation and printing quality control techniques of M3DPC-Rob show sufficient and steady accuracy that meet the requirements of construction engineering.

Microplastics (MP) pollution is a global issue that raises concerns about potential toxicity for environmental and human health. The notion that SARS-CoV-2 is more stable when adsorbed on plastic surfaces urged us to examine whether the virus can attach to MP, which may facilitate infection upon inhalation or ingestion. Here, we describe that MP can bind SARS-CoV-2 pseudovirus on their surface and enhance infection of human cells in vitro. This enhanced in vitroinfectivity was confirmed with authentic SARS-CoV-2, in parallel with increased expression of inflammation-related caspase-3, IL-8 and TNF-α genes. These results suggest that the presence of MP in the environment or in our respiratory or gastrointestinal tracts has the potential to interact with SARS-CoV-2, and potentially increase viral infectivity and spreading.

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Our study evaluated the hypothesis that gastric contractions may contribute to ischemia by increasing vascular resistance. Using an ex vivo segment of the dog's stomach as the experimental model, contractions were induced with platelet activating factor (PAF) and bethanechol, a cholinergic vasodilator. Spontaneous contractions produced slight increases in luminal pressure and corresponding increases in vascular resistance. PAF caused statistically significant, dose-dependent increases in the force of gastric contractions that were highly correlated with phasic changes in vascular resistance. To ensure that the relationship between contractions and vascular resistance was independent of vascular tone, we next examined responses to bethanechol. Bethanechol stimulated contractions that also transiently increased both luminal pressure and vascular resistance. Our results demonstrate that gastric contractions markedly increase vascular resistance and support the hypothesis that hypercontractility may contribute to the development of mucosal ischemia during ulceration.

This article presents a method of design, manufacturing, and measuring S-gear. S-gear is a kind of gear whose tooth profile is an S-shaped curve. The sine (cosine) gear, cycloid gear, polynomial gear, and circular arc gear are all S-gears in essence. In the S-gear transmission, the concave surface of one gear and the convex surface of the other gear contact each other. Therefore, the power transmitted by S-gear is much larger than that of the convex-convex-contact involute gear. Some scholars have studied the characteristics of S-gear, but few have explored its manufacturing. In this article, the Numerical Control (NC) machining technology of S-gear is studied in detail for its industrial application. The polynomial curve is used to construct the tooth profile of the S-gear based on the Gear Meshing Theory. The mathematical model of polynomial S-gear is established, by which involute gear can be represented as a special S-gear. The steps of generating NC codes are described. Then, the S-gear sample is processed with an NC machining center. Finally, the sample is measured with a Coordinate Measuring Machine (CMM), and the measurement results show that the accuracy of the S-gear processed by the NC machining center reaches ISO6. This research provides a feasible approach for the design, manufacturing, and measuring of S-gear.

A series of hierarchical ZSM-5 zeolites were prepared by seed induction method and alkali-treated method. The crystal structural, textural and acidic properties were characterized by XRD, TEM, NH3-TPD, and N2-sorption. The effect of hierarchical ZSM-5 zeolites on the product distribution of low rank coal fast pyrolysis in a fluidized bed was investigated. The results showed that the specific surface area, mesoporous pore volume and average pore size of the zeolites increase to different degrees after alkali treatment. Hierarchical ZSM-5 zeolites could promote the cyclization of aliphatics and the dissociation of phenol pool of volatile from coal pyrolysis, increasing the content of light aromatics. The yield of light aromatics reaches the maximumwhen the zeolites used are treated with 0.3 mol NaOH, in which the content of mono-aromatics and naphthalene/methylnaphthalene increases by 2.7 times and 0.9 times, respectively, compared with microporous zeolites. The performance of catalysts decreases when treated with 0.4 mol NaOH due to the excessive desilication.

The first highly enantioselective hydrogenation of carbocyclic aromatic amines has been successfully realized using in situ-generated chiral ruthenium complex as catalyst, affording facile access to chiral exocyclic amines with up to 98% ee.

As an effective solution toward the establishment of a sustainable society, the reductive transformation of CO2into value-added products is certainly important and imperative. Herein, we report a porphyrin metal–organic framework composite Au@Ir-PCN-222, which is obtained through the in situformation of Au nanoparticles in the coordination interspaces of Ir-PCN-222. Catalytic results show that Au@Ir-PCN-222 is highly efficient for CO2reduction and aminolysis, giving rise to formamides in high yields and selectivities under room temperature and atmospheric pressure. Mechanistic studies disclose that the high efficiency of Au@Ir-PCN-222 is due to the synergistic catalysis of Au NPs and Ir-PCN-222, in which Au NPs can adsorb CO2molecules on their surfaces and then increase the CO2concentration in the cavities of the framework, and at the same time, Au NPs transfer electrons to Ir-porphyrin units and therefore increase the interactions with CO2molecules.

Selenium (Se) is an essential trace element that has a large number of biological functions for broilers. However, the absorption kinetics of Se from sodium selenite in the small intestine of broilers remains unclear. Therefore, two experiments were conducted with 28-d-old commercial male broilers to study the kinetics of Se absorption in ligated small intestinal segments. In experiment 1, the Se absorption in duodenal, jejunal, and ileal segments at different post-perfusion time points (0, 20, 40, 60, 80, 100 and 120 min) were compared. In experiment 2, a kinetic study of Se absorption was conducted with the duodenal, jejunal, and ileal loops perfused with solutions containing 0, 0.0375, 0.075, 0.15, 0.30, or 0.60 μg mL−1of Se as sodium selenite, and Se contents in perfusates were determined at 100 min after perfusion. The results from experiment 1 showed that the Se absorption increased in an asymptotic response (P<0.0001) to post-perfusion time within 120 min in all the small intestinal segments, but increased linearly (P<0.0001) at less than 100 min after perfusion in duodenal and ileal segments, while more than 96.0% of the maximum Se absorption occurred at 100 min after perfusion in each small intestinal segment. In experiment 2, there was no difference (P>0.05) in the Se absorption rate among different ligated small intestinal segments perfused with solutions containing 0.0375–0.15 μg mL−1of Se, however, the Se absorption rate was higher (P<0.05) in the jejunum than that in the duodenum perfused with solutions containing 0.30–0.60 μg mL−1of Se. The kinetic curves of Se absorption demonstrated that the Se absorption was a saturated carrier-mediated process in the duodenum, and the maximum absorption rate was 1 271 pg min−1cm−1; whereas the Se absorptions were a non-saturated diffusion process in the jejunum and ileum, and the diffusive constants were 2 107 and 1 777 cm2min−1, respectively. The results from the present study indicate that the jejunum is the main Se absorption site, and the Se absorption is a saturated carrier-mediated process in the duodenum, but a non-saturated diffusion process in the jejunum and ileum of broilers.

The pathogenesis underlying the alterations of orbital architecture in Graves’ orbitopathy (GO) is not yet fully understood. The present study aimed to investigate the association of DNA methylation in peripheral blood and orbital volumetry in Chinese patients with GO.A total of 35 GO subjects (70 orbits) were subjected to CT scan. The total cross-sectional area of the extraocular muscles (orbital muscles, OM), total orbit area (TOA), and the exophthalmometry were measured and OM/TOA ratio was calculated. Targeted bisulfite sequencing was performed on seven candidate genes.No significant correlation was established between the DNA methylation levels of these genes and exophthalmometry. The MBPmethylation level was found to be correlated with OM/TOA ratio (P< 0.05). Multiple linear regression analysis on parameters including age, sex, TRAb, duration of GO, and DNA methylation levels of seven genes with OM/TOA ratio confirmed that MBPand OM/TOA ratio had a significant correlation (P< 0.05). The partial least squares analysis showed that the top three genes with the highest loadings were MBP, BOLL, and BECN1and that OM/TOA ratio affected the DNA methylation block than exophthalmometry.This study provided preliminary evidence that MBPis a potential gene associated with OM enlargement in GO patients according to the combination of DNA methylation sequencing and orbital CT measurement.

In this paper, an improved discharging circuit was proposed to quicken the decay of the current in the drive coil in a reluctance accelerator when the armature reaches the center of the coil. The aim of this is to prevent the suck-back effect caused by the residual current in drive coil. The method is adding a reverse charging branch with a small capacitor in the traditional pulsed discharging circuit. The results under the traditional circuit and the improved circuit were compared in a simulation. The experiment then verified the simulations and they had good agreement. Simulation and experiment both demonstrated the improved circuit can effectively prevent the suck-back effect and increase the efficiency. At the voltage of 800 V, an efficiency increase of 36.34% was obtained.

As a further exploration of the asymmetrically substituted diiron models for the active site of [FeFe]-hydrogenases, two new types of small bite-angle aminodiphosphine [(Ph2P)2NR; denoted as PNP in this study]-chelated diiron N-phenyl-aza- and ethanedithioate complexes Fe2(μ-xdt)(CO)4{κ2-(Ph2P)2NR} (1a–1e) and (2a–2e), respectively, were successfully synthesized by the carbonyl substitution reactions of all-carbonyl diiron complexes Fe2(μ-xdt)(CO)6(xdt = SCH2N(Ph)CH2S (adtNPh) and SCH2CH2S (edt)) with PNP (PNP = (Ph2P)2NR, R = CMe3, CH2CHMe2, (CH2)3Me, (CH2)3Si(OEt)3, and (CH2)3NMe2) in the presence of Me3NO·2H2O or UV irradiation. All the new complexes obtained above have been well characterized by elemental analysis, FT-IR, NMR spectroscopy, and particularly for 1a, 1b, 2a, and 2dby single-crystal X-ray diffraction analysis. By comparison, 31P{1H} NMR and X-ray crystallographic studies have clearly revealed that the change of the dithiolate bridge from adtNPhto edt has a significant influence on the coordination geometry of the chelating PNP ligands in Fe2S2complexes, in which the basal–basal configuration in the adtNPhcomplexes 1a–1eis favorable whereas the apical–basal conformation in the edt complexes 2a–2eis main. In addition, the electrochemical properties of complexes 1band 2bas a pair of representative counterparts are evaluated and compared by cyclic voltammetry in the absence and presence of HOAc as a proton source, indicating that they are found to be electrocatalytically active.

Complementary metal-oxide-semiconductor (CMOS) sensors can convert X-rays into detectable signals; therefore, they are powerful tools in X-ray detection applications. Herein, we explore the physics behind X-ray detection performed using CMOS sensors. X-ray measurements were obtained using a simulated positioner based on a CMOS sensor, while the X-ray energy was modified by changing the voltage, current, and radiation time. A monitoring control unit collected video data of the detected X-rays. The video images were framed and filtered to detect the effective pixel points (radiation spots). The histograms of the images prove there is a linear relationship between the pixel points and X-ray energy. The relationships between the image pixel points, voltage, and current were quantified, and the resultant correlations were observed to obey some physical laws.

When the sediment and the dissolved matter laden in the river meet a clear water in reservoirs, the turbid water will plunge and spread into the clear water, forming the turbidity current and influencing the water quality and the life of the reservoir. Due to the unsteady nature of the flood, the turbidity current is unsteady. In the present study, we use the MIKE 3 computational fluid dynamics code to simulate continuous and discontinuous turbidity currents on a flat slope. With the model used by us, the turbulence is divided into two parts: the horizontal turbulence and the vertical turbulence, which are separately modeled by the Smagorinsky model and our model to capture the anisotropic turbulence. In this model, the sediment settling and deposition are considered. The simulation results concerning the flume water surface level, the front velocity and sediment concentration profiles are found consistent with the experimental data, particularly, for the sediment concentration profiles with an absolute mean error of 0.026 kg/m3and the root mean square error of 0.046 kg/m3. This finding suggests that this model can be used to well predict the turbidity current on the flat slope.

ABSTRACTEffects of parameters including temperature, time and coal ratio on the reduction behaviour of preheated iron-bearing converter sludge pellets in a simulated rotary kiln are studied through orthogonal tests. ANOVA analyses show that reduction time and temperature have remarkable influence on the metallisation degree, occupying 55.02 and 30.08% of the total contribution, while temperature is the most significant factor affecting the compressive strength, with 90.98% contribution. The metallisation degree increases with the increasing time from 1.5 to 2.5 h, and first increases and then decreases with the increasing temperature from 1000 to 1100°C. The compressive strength increases with the increasing temperature. Under the optimal condition of temperature 1050°C, time 2.5 h, coal ratio 1.3, the metallisation degree is 72.92%, and the compressive strength is 1310 N/p, which satisfies the requirement of iron burden for blast furnace.

The tedious sample preparation for flow cytometry limits the throughput and thus its usage as a primary screening method despite its sensitivity and accuracy. With the growing focus on utilizing antibodies as a therapeutic modality in drug discovery, it is critical to develop a high-throughput flow cytometry (HTFC) workflow to cope with the increasing need to support antibody discovery programs. We have developed a seamless HTFC sample preparation and readout workflow using the HighRes modular robotic system and the IntelliCyt iQue Screener PLUS. To fully utilize the advantages offered by flow cytometry, we typically multiplex multiple cell lines of interest in one well to simultaneously quantitate on-target activity and nonspecific activity along with measurement of antibody concentration. The ability to measure multiple parameters coupled with speed and increased accuracy provides gains in productivity and helps speed up antibody lead discovery.

The tedious sample preparation for flow cytometry limits the throughput and thus its usage as a primary screening method despite its sensitivity and accuracy. With the growing focus on utilizing antibodies as a therapeutic modality in drug discovery, it is critical to develop a high-throughput flow cytometry (HTFC) workflow to cope with the increasing need to support antibody discovery programs. We have developed a seamless HTFC sample preparation and readout workflow using the HighRes modular robotic system and the IntelliCyt iQue Screener PLUS. To fully utilize the advantages offered by flow cytometry, we typically multiplex multiple cell lines of interest in one well to simultaneously quantitate on-target activity and nonspecific activity along with measurement of antibody concentration. The ability to measure multiple parameters coupled with speed and increased accuracy provides gains in productivity and helps speed up antibody lead discovery.

In order to investigate the ultimate load capacity of K-type tube-gusset plate connections with stiffened plate, the static tests of five full-scale specimens were conducted in this study. The results indicate that the end stiffened plate is critical for improving the load capacity of the connections. In addition, the parametric nonlinear finite element analysis of the K-type tube-gusset plate specimens was performed with account of such non-dimensional parameters as chord diameter-to-thickness ratio (γ), plate width-to-chord diameter ratio (α), plate thickness-to-chord thickness ratio ($$\tau_{1}$$ τ1 ), stiffened plate thickness (td), and nominal-to-yield stress ratio (η). The above analysis implies that the ultimate load capacity decreases with the increment of γand increases with the increment of αand $$\tau_{1}$$ τ1 , while it is only slightly affected by the stiffened plate thickness. Compare the results of the finite element analysis with assessment by design guides existing. Based on the former results, an equation for estimating the load capacity of K-type tube-stiffened gusset plate is proposed.

Excess iron deposition in the brain often causes oxidative stress-related damage and necrosis of dopaminergic neurons in the substantia nigra and has been reported to be one of the major vulnerability factors in Parkinson’s disease (PD). Iron chelation therapy using deferoxamine (DFO) may inhibit this nigrostriatal degeneration and prevent the progress of PD. However, DFO shows very short half-life in vivoand hardly penetrates the blood brain barrier (BBB). Hence, it is of great interest to develop DFO formulations for safe and efficient intracerebral drug delivery. Herein, we report a polymeric nanoparticle system modified with brain-targeting peptide rabies virus glycoprotein (RVG) 29 that can intracerebrally deliver DFO. The nanoparticle system penetrates the BBB possibly through specific receptor-mediated endocytosis triggered by the RVG29 peptide. Administration of these nanoparticles significantly decreased iron content and oxidative stress levels in the substantia nigra and striatum of PD mice and effectively reduced their dopaminergic neuron damage and as reversed their neurobehavioral deficits, without causing any overt adverse effects in the brain or other organs. This DFO-based nanoformulation holds great promise for delivery of DFO into the brain and for realizing iron chelation therapy in PD treatment.

Small ubiquitin-like modifier (SUMO) family proteins regulate target-protein functions by post-translational modification. However, a potent and selective inhibitor targeting the SUMO pathway has been lacking. Here we describe ML-792, a mechanism-based SUMO-activating enzyme (SAE) inhibitor with nanomolar potency in cellular assays. ML-792 selectively blocks SAE enzyme activity and total SUMOylation, thus decreasing cancer cell proliferation. Moreover, we found that induction of the MYC oncogene increased the ML-792-mediated viability effect in cancer cells, thus indicating a potential application of SAE inhibitors in treating MYC-amplified tumors. Using ML-792, we further explored the critical roles of SUMOylation in mitotic progression and chromosome segregation. Furthermore, expression of an SAE catalytic-subunit (UBA2) S95N M97T mutant rescued SUMOylation loss and the mitotic defect induced by ML-792, thus confirming the selectivity of ML-792. As a potent and selective SAE inhibitor, ML-792 provides rapid loss of endogenously SUMOylated proteins, thereby facilitating novel insights into SUMO biology.

A setup based on CMOS sensor and ARM microcontroller is designed to measure the γ-rays. STM32F103 is used as the main platform to control real-time online analysis of the image collected by the OV7670 CAMERACHIP™ and send the image into the LCD at the desired frame rate. Accuracy of sampling interval can be regulated and controlled. The frame number of image is adjusted by STM32F103 to achieve better monitoring. Two methods are adopted to analyze the image data from the CMOS sensor. Although the CMOS sensor is of low efficiency for γ-ray detection, the results show that it is able to discriminate the 60Co γ-rays.

A novel antibacterial biomimetic porous titanium implant with good osseointegration was prepared by freeze-casting and thermal oxidation. Bone integration properties of the porous titanium implant were evaluated by cell proliferation assay, alkaline phosphatase activity assay, X-ray examination and hard bone tissue biopsy. The in vitro cell proliferation and the level of differentiation of the group with a modified nano-porous implant surface were significantly higher than those in the group without surface modification and the dense titanium control group (P<0.05). In vivo, bone growth and osteogenesis were found in the experimental groups with modified and unmodified porous titanium implants; osteoblasts in the modified group had more mature differentiation in the pores compared to the unmodified group. Such implants can form solid, biologically compatible bone grafts with bone tissues, exhibiting good osseointegration.

This work aimed to prepare the nanospike surface-modified bionic porous titanium implants that feature favorable osteointegration performance and anti-bacterial functions. The implant was prepared using freeze casting, and nanospike surface-modification of the implant was performed using thermal oxidation. The pore morphology and size, mechanical properties, and osteogenic performance of the implants were analyzed and discussed. The results showed that when the volume ratio of titanium powder in slurry was set to be 10%, the porosity, pore diameter, compressive strength, and elastic modulus of the porous samples were (58.32±1.08)%, (126.17±18.64) μm, (58.51±20.38) MPa and (1.70±0.52) GPa, respectively. When the porous sample was sintered at a temperature of 1200 °C for 1 h, these values were (58.24±1.50)%, (124.16±13.64) μm, (54.77±27.55) MPa and (1.63±0.30) GPa, respectively. The nanospike surface-modified bionic porous titanium implants had favorable pore morphology and size, mechanical properties and osteointegration performance through technology optimization, and showed significant clinical application prospect.

An efficient asymmetric Friedel–Crafts reaction has been developed for the synthesis of optically active quaternary α-aminophosphonates with up to 98% ee. The synthesis involves the reaction of cyclic α-ketiminophosphonates with indoles using an H8-BINOL-derived chiral phosphoric acid (CPA) catalyst that bears electron-withdrawing 3,5-ditrifluoromethylphenyl substituents on its 3- and 3′-positions. This Friedel–Crafts reaction of cyclic α-ketiminophosphonates was also successful with pyrrole.

In order to improve the machining accuracy and production efficiency of face-gear, a method of face-gear generating hobbing by worm is provided in this paper. The principle of face-gear hobbing worm is analyzed, and the mathematical model of the worm is presented based on the principle and the theory of meshing. Taking the hobbing needs into account, the special machine tool is provided, and the movement control method of face-gear hobbing by the worm on the machine tool is proposed. The equation of face-gear tooth surface is calculated, and the 3-D model of face-gear is established based on CATIA software. To reduce the face-gear tooth profile errors induced by ratio errors, an error analysis model of face-gear hobbing is established. The experiment is carried out, and the completed specimen is detected by Coordinate Measuring Machining (CMM). The processing parameter is amended according to the tooth flank detection results, and the maximum normal deviation of the whole tooth surface of the face-gear specimen is improved from 243.2 µm to 61.0 µm. Experiment results demonstrate that the method of face-gear hobbing by worm is an effective approach to achieve the precision face-gear with high dimensional accuracy.

A robust primitive diamond-type topology 3-D metal–organic framework (MOF) of {[Cd4(hbhdpy)2(bdc)3(DMA)2]·(H2O)4}n(1, DMA = N,N-dimethylacetamide) was constructed from the planar secondary building units of the dinuclear cadmium clusters, Cd2(μ2-O)2, and two linear organic linkers of the new multidentate Schiff base of 4-(2-hydroxy-3-methoxy-benzyli-denehydrazino-carbonyl)-N-pyridin-4-yl-benzamide (Hhbhdpy) through the solvothermal reaction. 1presents a 2-fold interpenetrating network along with confined narrow channels and rich acylamide groups as well as potential metal open sites for excellent selective CO2uptake over CH4/N2and high luminescent response for 2,4,6-trinitrophenol (TNP) in DMA solution under ambient conditions. With 2-amino-1,4-dicarboxy-benzene (H2bdc-NH2) replacing H2bdc, an amine-functionalized MOF of {[Cd4(hbhdpy)2(bdc-NH2)3(DMA)2]·(H2O)4}n(1-NH2) as an isomorphism of 1, was synthesized under the same reaction conditions. Compared with 1, the corresponding bifunctional features of 1-NH2is more obvious. To the best of our knowledge, it is the first reported interpenetrating Cd-MOFs with highly sensitive luminescence response for TNP molecules combined with excellent selectivity for CO2/N2and CO2/CH4.

In this study, fatigue properties and fracture mechanism of dissimilar Al–Mg–Si/Al–Zn–Mg aluminum alloys friction stir welding (FSW) joints were investigated and the effect of the sheet configuration on the fatigue behavior of the FSW joints was also discussed. Results showed that the joints owned better fatigue properties when the Al–Zn–Mg aluminum alloy was placed at the advancing side (AS). At 107cycles, the fatigue strengths of Al–Zn–Mg–AS and Al–Mg–Si–AS joints were, respectively, 105.6 and 90.1 MPa. All joints fractured at the heat-affected zone at the Al–Mg–Si alloy side. Transmission electron microscopy results showed that better fatigue property of the Al–Zn–Mg–AS joint was associated with the bridging effect of the bigger secondary phase particles.

Erythropoietic protoporphyria (EPP), an autosomal dominant disease, is caused by partial deficiency of ferrochelatase (FECH), which catalyzes the terminal step of heme biosynthesis because of loss-of-function mutations in the FECHgene. To date, only a few cases have been described in Asia. In this study, we describe the clinical features of two Chinese patients with EPP, with diagnosis confirmed by the increase of free protoporphyrin in erythrocytes, detection of plasma fluorescence peak at 630–634 nm, and analysis of FECHgene mutations. Using gene scanning, we identified a small deletion in the FECHgene (c.973 delA) in one proband (patient A) and a pathogenic FECHmutation (c.1232 G>T) in the other (patient B) and also observed some nucleotide variations (c.798 C>G, c.921 A>G, IVS1−23 C>T, IVS3+23 A>G, IVS9+35 C>T, and IVS3−48 T>C) in these patients. The family pedigree of patient A was then established by characterization of the genotype of the patient’s relatives. We also analyzed the potential perniciousness of the missense mutation with bioinformatic software, Polyphen and Sift. In summary, Chinese EPP patients have similar manifestations to those of Caucasians, and identification of the Chinese FECHgene mutations expands the FECHgenotypic spectrum and may contribute to genetic counseling.

Background: Anti-N-methyl-d-aspartate (NMDA) receptor encephalitis is an autoimmune disorder characterized by complex neuropsychiatric syndromes during disease onset. Although this disease has been well documented in the last decade, clinical characteristics of anti-NMDA receptor encephalitis in patients with long-term diagnostic history of mental disorders remain unclear. Methods: Here, we reviewed and analyzed series of anti-NMDA receptor encephalitis patients with a long-term medical history of psychiatric disorders through a review of literature using PubMed, web of science and Embase database. In addition, we described a patient of anti-NMDA receptor encephalitis with a long-term history of major depressive disorder. Results: A total of 14 patients with anti-NMDA receptor encephalitis and a long-term history of mental disorders were included in our study. We found that most patients were adult (92.9%) and female (78.6%). These patients often first visited a psychiatric department (71.43%). The mean disease course of psychiatric disorders was more than 9 years. Speech impairment (71.4%), abnormal behaviors (64.3%), and catatonia (64.3%) were the most common clinical symptoms. Most patients (85.7%) had a satisfactory prognosis after immunotherapy. Conclusion: Anti-NMDA receptor encephalitis in individuals with mental disorders is an underestimated condition, yet it presents complex clinical symptoms. Mental and behavioral impairments are more frequently observed in newly diagnosed anti-NMDA receptor encephalitis patients with a long-term history of mental disorders than those without mental illness. A diagnosis of anti-NMDA receptor encephalitis should be considered when patients with mental illness show sudden fluctuations in psychiatric symptoms.

This paper summarizes recent studies on the effects of urbanization on climate in China. The effects of urbanization on local climate trends have been re-estimated based on homogenized observations and using improved methods. In this respect, the effect of urbanization on the observed warming trend of local surface air temperatures during the last few decades is determined as being about 20% at urban stations such as the Beijing Observatory. The large-scale weakening trend of wind speed is also about 20% more prominent at the city center than its surroundings. The effect of urbanization on precipitation is not profound, but results of high-resolution regional climate modeling suggest that this effect may depend on the urban extent. Although the urban heat island (UHI) should favor local atmospheric convection and hence precipitation, the increasingly extending urban land-use may reduce precipitation over the urban cluster in North China. It is found that urbanization can play a more notable role in extreme events than usual weather. High-resolution simulations show a positive feedback between the UHI and the super-heat wave in Shanghai during July–August 2013. Relevant studies dealing with urban climate adaptation are discussed in relation to recent findings.

To improve the machining accuracy and production efficiency of face gears, this article presents a generating milling method for the spur face gear using a five-axis computer numerical control milling machine and proposes a milling principle of the spur face gear using a milling cutter. Based on the milling principle and theory of gearing, a mathematical model of the spur face gear milling cutter is established, and the design parameters of the cutter are determined. Considering the requirements of machine motion during the face gear milling process, a five-axis computer numerical control milling machine is developed to produce the face gear. Based on the structure of the milling machine, a mathematical model of the spur face gear is established, and a milling method is proposed. The spur face gear milling cutter is manufactured, and the face gear milling experiments are conducted on the self-developed milling machine. The measurement results of the tooth surface deviations indicate that the maximum deviation is 22.6 µm, and that the machined spur face gear accuracy can meet the requirements of roughing. The experimental results verify the validity of the proposed generating milling method and demonstrate that the generating milling method is an effective approach to improve the accuracy and efficiency of the spur face gear.

Palladium nanoparticles (Pd NPs) were fabricated by using insulin amyloid fibrils (INSAFs) as biotemplates. Atomic force microscopy measurements showed that ultra-small Pd NPs were well adsorbed and dispersed on surfaces of INSAFs. X-ray photoelectron spectroscopy confirmed the partial reduction of Pd ion into metallic Pd(0) probably due to the presence of Cys groups on surface of the insulin fibrils. The electrochemical performance of Pd/INSAFs to reduction of H2O2was further evaluated by cyclic voltammetry. The remarkably high electrocatalytic activity, low detection limitation and excellent stability make the Pd/INSAFs a promising bio-nanoelectrocatalyst.

AbstractThere have long been arguments about the impact of urbanization on local meteorological observations. This letter reviews up-to-date studies of the urbanization-related warming in the observed land surface air temperature series in China. Many previous studies have suggested that, over the past few decades, the local warming due to urbanization could have been about 0.1 °C/10 yr, or even larger. However, based on recently developed homogenized temperature records, the estimated urban bias is smaller. Major uncertainties arise from either the data quality or the techniques used to estimate the urbanization effect. A key example is the ‘observation-minus-reanalysis’ method, which tends to overestimate the urban signal in this region, partly due to systematic bias in the multi-decadal variability of surface air temperature in the reanalysis data. It is expected that improved numerical modeling with high-resolution information regarding the changing land surface in the region will help to further understand and quantify the effect of urbanization in local temperature records.

The genetic mechanisms of the secondary pore development zones in the lower part of the fourth member of the Shahejie Formation (Es4x) were studied based on core observations, petrographic analysis, fluid inclusion analysis, and petrophysical measurements along with knowledge of the tectonic evolution history, organic matter thermal evolution, and hydrocarbon accumulation history. Two secondary pore development zones exist in Es4x, the depths of which range from 4200 to 4500 m and from 4700 to 4900 m, respectively. The reservoirs in these zones mainly consist of conglomerate in the middle fan braided channels of nearshore subaqueous fans, and the secondary pores in these reservoirs primarily originated from the dissolution of feldspars and carbonate cements. The reservoirs experienced “alkaline–acidic–alkaline–acidic–weak acidic”, “normal pressure–overpressure–normal pressure”, and “formation temperature increasing–decreasing–increasing” diagenetic environments. The diagenetic evolution sequences were “compaction/gypsum cementation/halite cementation/pyrite cementation/siderite cementation–feldspar dissolution/quartz overgrowth–carbonate cementation/quartz dissolution/feldspar overgrowth–carbonate dissolution/feldspar dissolution/quartz overgrowth–pyrite cementation and asphalt filling”. Many secondary pores (fewer than the number of primary pores) were formed by feldspar dissolution during early acidic geochemical systems with organic acid when the burial depth of the reservoirs was relatively shallow. Subsequently, the pore spaces were slightly changed because of protection from early hydrocarbon charging and fluid overpressure during deep burial. Finally, the present secondary pore development zones were formed when many primary pores were filled by asphalt and pyrite from oil cracking in deeply buried paleo-reservoirs.

In order to analyze the factors influencing sandstone mechanical compaction and its physical property evolution during compaction processes, simulation experiments on sandstone mechanical compaction were carried out with a self-designed diagenetic simulation system. The experimental materials were modern sediments from different sources, and the experiments were conducted under high temperature and high pressure. Results of the experiments show a binary function relation between primary porosity and mean size as well as sorting. With increasing overburden pressure during mechanical compaction, the evolution of porosity and permeability can be divided into rapid compaction at an early stage and slow compaction at a late stage, and the dividing pressure value of the two stages is about 12 MPa and the corresponding depth is about 600 m. In the slow compaction stage, there is a good exponential relationship between porosity and overburden pressure, while a good power function relationship exists between permeability and overburden pressure. There is also a good exponential relationship between porosity and permeability. The influence of particle size on sandstone mechanical compaction is mainly reflected in the slow compaction stage, and the influence of sorting is mainly reflected in the rapid compaction stage. Abnormally high pressure effectively inhibits sandstone mechanical compaction, and its control on sandstone mechanical compaction is stronger than that of particle size and sorting. The influence of burial time on sandstone mechanical compaction is mainly in the slow compaction stage, and the porosity reduction caused by compaction is mainly controlled by average particle size.