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Climate change and urbanization have led to an increase in extreme weather and urban heat islands. Green space can help regulate the thermal environment, but previous studies have focused on two-dimensional (2D) indicators, neglecting the intrinsic three-dimensional (3D) characteristics of green space. Therefore, we developed a set of 3D landscape indices to define green space configurations, including characteristic, shape, and compactness, based on landscape ecology and the law of universal gravity, and quantify its benefits for the thermal environment. We collected high-resolution LiDAR point cloud data from Siming Mountain, China, to calculate both 2D and 3D green space landscape patterns and investigate their effects on land surface temperature (LST) using correlation analysis and spatial statistical methods. Our study revealed: (1) All the selected green space landscape indices had a significant negative effect on LST, with a non-linear enhancement when 2D or 3D indices interacted. (2) The 3D compactness index (VCI) could be the most reliable and concise index to explain LST spatial distribution. Adjusting the VCI allowed us to reduce the LST of the study area by up to 3.71 °C in summer and 2.14 °C in winter. However, an overly compact 3D green space above the threshold could lead to higher LST in summer. (3) Terrain had a weaker effect on LST in winter than in summer, and it showed a stronger interaction with the 3D form of green space than with the 2D form. We concluded that the 3D compact form of green space can be utilized as the key factor in maximizing its cooling effect, by taking into account both terrain factors and seasonal variations. Our study can shed light on the scientific planning of green space aiming at optimizing the thermal environment for more sustainable forest and urban habitats.

Building sector consists of a major part of global energy consumption and carbon emission. Reducing energy consumption in buildings can make a substantial contribution towards the strategic goal of carbon neutrality. Building energy consumption carbon emission (BECCE) is highly correlated with microclimate. Green space has long been recognized as the natural way to improve the microclimate and reduce BECCE. However, the effective distance and optimized configuration of green space for the reduction in BECCE are hardly known. To this purpose, we developed a green space compactness (GSC) index as an indicator of microclimate around the People’s Bank, located in 59 cities across China, and used statistical, deep learning, and spatial analysis methods to obtain the most effective distance with respect to the effect of GSC on BECCE. We used hot and cold spot spatial analysis methods to detect the spatial heterogeneity of BECCE and analyzed the corresponding GCS to discover the optimal way for BECCE reduction. The results clearly showed that BECCE was highly correlated with the GSC, and the influence of GSC on BECCE was the highest at the distance of 250 m from the building. The hot and cold spots analysis suggested that BECCE has a significant spatial heterogeneity, which was much higher in the north part of China. Improving the configuration of green space for certain cities could lead to considerable emission reductions. If the BEECE is reduced from 4675 tons to 486 tons, the GSC needs to be increased from 0.39 to 0.56. The study suggests that 250 m is the most effective distance to reduce BECCE, and optimal green space configuration can provide a feasible way to mitigate carbon emissions and valuable information for the development of low-carbon cities.

Abstract Hypoxic-ischemic encephalopathy (HIE) is a diffuse brain tissue injury caused by acute ischemia and hypoxia, and it is most commonly found in newborn infants but can also occur in adults. Mesenchymal stem cell (MSC) therapies have showed improved outcomes for treating HIE-induced neuronal defects. However, many key issues associated with poor cell viability and tolerance of grafted MSCs after HIE remain to be resolved. Genetic engineering could endow MSCs with more robust regenerative capacities. Our research, along with that of other scientists, has found that the expression of intracellular erythropoietin (EPO) in human umbilical cord MSCs (hUC-MSCs) increases proportionally with the duration of hypoxia exposure. Furthermore, we observed that EPO, when introduced into the EPO gene-modified hUC-MSCs, can be secreted into the extracellular space. However, the underlying mechanisms that support the neuroprotective effects of EPO-MSCs remain unclear. EPO-MSCs, hUC-MSCs, and NC-MSCs were identified by flow cytometry, osteogenic, and adipogenic differentiation assays. The oxygen-glucose deprivation (OGD)-induced SH-SY5Y cell-line was established, and five groups were set up: control, 24-h ischemia-hypoxia, co-cultured with hUC-MSCs, NC-MSCs, and EPO-MSCs after hypoxia. LEGENDplex™ multi-factor flow cytometry was used to detect the secretion of inflammatory factors in cell supernatants and cerebrospinal fluid. Chromosome-targeted excision and tagging (CUT&Tag) sequencing was applied to detect genomic H3K4me2 modifications, and conjoint analysis with transcriptome sequencing (RNA-seq) was performed. Lentiviral vector infection was used to construct SH-SY5Y cells with stable knockdown of RE1-silencing transcription factor (REST), and flow cytometry was used to detect alterations in apoptosis. Finally, the molecular mechanism underlying the neuroprotective and anti-apoptotic effects of EPO-MSCs was investigated using RNA sequencing, qRT-PCR, and western blot assays. Our results suggest that EPO-MSCs are genetically engineered to secrete significantly more EPO. EPO-MSCs treatment has anti-apoptotic properties and offers neuronal protection during ischemic-hypoxic injury. Furthermore, RNA-seq results suggest that multiple inflammation-related genes were down-regulated after EPO-MSCs treatment. Application of RNA-seq and CUT&Tag combined analysis found that the expressions of REST were significantly up-regulated. Lentiviral vector infection to construct REST knockdown SH-SY5Y failed to rescue apoptosis after hypoxia and co-culture with EPO-MSCs, and SETD2-mediated H3K36me3 protein level expression was reduced. EPO-MSCs may promote neuronal survival by affecting H3K4me2 and thus activating the expression of REST and TET3. EPO-MSCs also upregulated the modification level of SETD2-mediated H3K36me3 and regulated the expression of inflammation-related genes such as PLCG2, as well as apoptosis genes BCL2A1. To investigate the neuroprotective effects of EPO-modified hUC-MSCs and the underlying epigenetic regulatory mechanisms, this study aims to provide a theoretical foundation for the potential application of EPO gene-modified hUC-MSCs in the treatment of HIE.

The ductile forming process of a polymer in a standard screw extruder and pin-barrel extruder, equipped with or without a field synergy elongation screw, was investigated by the finite element method. In order to assess the mixing and heat transfer capabilities of screws, characteristic parameters such as the mixing efficiency, segregation scale, and temperature distribution of different structures were analyzed and compared. The results indicated that the flow pattern of the polymer melt in the extruder was significantly influenced by the screw structure and was improved by the newly designed field synergy screw configuration, which brought a desirable elongational flow to enhance the radial convection. This was attributed to the unique radial wedge-shaped repeated convergence region of the field synergy elongation screw, increasing the synergistic effect between the velocity field, velocity gradient field, and temperature gradient field and thus improving the heat transfer and mixing efficiency. After adding barrel pins, the flow was forced to split, resulting in a more significant stretching effect on the melt. The field synergy effect in the pin mixed region was strengthened, which further increased the heat and mass transfer efficiency of the screw. However, increasing barrel pins could also lead to undesired temperature fluctuation and flow resistance, which have a negative impact on the melt uniformity. This study offers an important reference for optimizing screw structure to obtain strong mixing and heat transfer performances.

Abstract On base of the content of Pb in the soil under different land use patterns in Lanping Lead-zinc mining area, Yunnan in southwest China, the root morphology and leaf traits of maize in different concentration Pb (20, 40, 60, 80, 100, 150, 200, 500, 1000, 2000, 3000 mg/L) were analyzed. The results showed that maize germination rate, germination vigor and growth index decreased with the increase of Pb concentration. The root length, surface area of maize increased by 0.21%–81.58%, 8.99%–73.43%, 1.50%–77.37%, respectively, under 20–500 mg/L Pb concentration. However, these parameters under 1000–3000 mg/L Pb concentration decreased by 37.86%–553.54%, 44.99%–766.16%, 55.99%–92.81%, respectively, and these lowest value appeared in 3000 mg/L Pb treatment. The root volume of maize increased by 4.57%–89.25% in 20–80 mg/L Pb concentration, and it decreased with the increase of Pb concentration when the Pb concentration was higher than 80 mg/L and decreased by 94.13% in 3000 mg/L Pb. The root surface area and length of 0.50–1.00 diameter class were higher than those of other diameter classes, and these value of maize under 500 mg/L Pb were higher than those of other concentrations. The length and perimeter of maize leaves with the highest value of 220.36 and 962.68 mm, respectively appeared in 60 mg/L Pb treatment. The leaf width and area of maize with the highest value of 15.68 mm and 2448.31 mm2, respectively, appeared in 40 mg/L Pb treatment, which indicated that the leaf traits of maize were promoted by low concentration Pb and inhibited by high concentration Pb.

Abstract Archaeological objects based on copper alloys (such as bronze wares) usually suffer from “bronze disease” that results from the existence of CuCl on the surfaces. The surface-coating Cu2(OH)3Cl can release Cl− and lead to further corrosion during the storage procedure. The central aim of the work is the verity the effectiveness of low-temperature radio-frequency (RF) plasma for the removal of CuCl and Cu2(OH)3Cl from the bronze wares. In this work, CuCl and Cu2(OH)3Cl patina were synthesized on copper by a simple solution method. The chemical and aesthetic features before and after plasma treatment were characterized using optical microscopy (OM), SEM-EDS, XRD, and XPS. The results show that Ar-H2 plasma could reduce the CuCl to Cu efficiently, which achieves pleasing esthetics as well as removes the chlorine (Cl atomic ratio decrease from 46.0 to 3.6%). For Cu2(OH)3Cl, the air plasma treatment exhibit better performance compared to the Ar-H2 plasma treatment, judging from the aesthetic effect and the removal effect of chlorine (Cl atomic ratio decrease from 14.8 to 3.3%).

Abstract Pb, Cu, Cd, Zn content of soil in mining areas and abandoned land, flats of the Pijiang River and farmlands were investigated. On this basis of soil heavy metal pollution, the changes of antioxidant enzyme system in maize (Qiandan 88) under different Pb concentrations (0, 20, 40, 60, 80, 100, 150, 200, 500, 1000, 2000, 3000 mg/L) stress were studied. The results show that the content of Pb, Cu, Cd, and Zn in soil is the highest in mining areas and abandoned land, followed by flats of the Pijiang River > farmlands, and that the variation range of Pb, Cu, Cd in mining areas and abandoned land are 106.40–2564.72, 14.83–490.88, 22.57–712.77 mg/kg, respectively, which are higher than that of the other land use types. When maize is under stress of 20–500 mg/L Pb concentration, T-SOD activity of maize leaves increase with the increase of Pb concentration and the highest value is 50.21 U/mg prot, but under Pb concentration > 1000 mg/L stress, T-SOD activity of maize leaves decrease gradually. The activity of POD decreases with the increases of Pb concentration, and the lowest POD activity of leaves in maize with the value of 93.24 U/mg prot is appeared in Pb 1000 mg/L concentration treatment group. MDA content in leaves of maize increases with the increase of the Pb concentration and the highest value is 101.98 nmol/mg prot, then the content of MDA decreases gradually when the Pb concentration is more than 500 mg/L, which indicates that the membrane lipid peroxidation of maize leaves under high concentration of Pb stress is serious and leads to the cell damage.

Abstract Purpose The fundamental cause of intrauterine adhesions (IUAs) is the destruction and reduction in stem cells in endometrial basal layer, resulting in endometrial reconstruction very difficult. The purpose of this study was to investigate the effects and underlying mechanism of human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) on the endometrial reconstruction after transplantation. Methods hUCB-MSCs were isolated and identified by flow cytometry, osteogenic, adipogenic and chondrogenic differentiation assays. The rabbit IUA models were established and set five groups (control, 14/28th day after surgery, estrogen and hUCB-MSCs treatment). The number of endometrial glands and the fibrosis rate were evaluated using HE and Masson staining, respectively. Endometrial proliferation, angiogenesis and inflammation were evaluated by immunohistochemical staining of ER, Ki-67and TGF-β1, respectively. Single-cell RNA sequencing (scRNA-seq) was applied to explore the cell differentiation trajectory after hUCB-MSCs transplanted into IUA endometrium. Finally, molecular mechanism of hUCB-MSCs repairing damaged endometrium was investigated by RNA sequencing, qRT-PCR and Western blot assays. Results After transplantation of the hUCB-MSCs, the increase in endometrial gland number, estrogen receptor (ER) and Ki-67 expression, and the decrease in fibrosis rate and TGF-β expression (P

Abstract High‐damping acoustic composites with unique sound insulation feature is reported, demonstrating surprisingly stable soundproof properties over a wide bandwidth of frequency (63–6300 Hz) with good mechanical properties. The extraordinary acoustic properties are attributed to the multiscale synergy of lamellar and hollow structures by multifillers adding. The acoustic composites are designed and fabricated through a low‐temperature one‐time rubber mixing process using nitrile butadiene rubber(NBR), chloroprene rubber (CR) as matrix and mica powder (MP), hollow glass beads (HGB), and montmorillonite (MMT) as multifillers. The soundproof mechanism is discussed in detail. Results indicate that the synergism of damping and sound absorption behaviors in the composition has a considerable impact on the acoustic characteristics, which can be controlled by the blending ratio of NBR/CR matrixes and the multiscale structures of MP/HGB/MMT multifillers. The designed multifillers acoustic composites can adapt to broadband engineering noise control including walls in express train constructions, panels of vessel or aircraft cabins, and large transportation pipelines.

Trauma-induced osteonecrosis of the femoral head (TI-ONFH) is a pathological process in which the destruction of blood vessels supplying blood to the femoral head causes the death of bone tissue cells. Vascular cell adhesion molecule 1 (VCAM-1) has been shown to have potent proangiogenic activity, but the role in angiogenesis of TI-ONFH is unclear. In this work, we discovered that VCAM-1 was significantly downregulated in the bone marrow mesenchymal stem cells (BMSCs) derived from patients with TI-ONFH. Subsequently, we constructed BMSCs overexpressing VCAM-1 using a lentiviral vector. VCAM-1 enhances the migration and angiogenesis of BMSCs. We further performed mRNA transcriptome sequencing to explore the mechanisms by which VCAM-1 promotes angiogenesis. Gene ontology biological process enrichment analysis demonstrated that upregulated differentially expressed genes (DEGs) were related to blood vessel development. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis revealed that upregulated DEGs were engaged in the Apelin signaling pathway. Apelin-13 is the endogenous ligand of the APJ receptor and activates this G protein-coupled receptor. Treatment with Apelin-13 activated the Apelin signaling pathway and suppressed the expression of cellular communication network factor 2 in BMSCs. Furthermore, Apelin-13 also inhibits the migration and angiogenesis of VCAM-1-BMSCs. In summary, VCAM-1 plays an important role in vascular microcirculation disorders of TI-ONFH, which provides a new direction for the molecular mechanism and treatment of TI-ONFH.

Multiple functional-material-filled nitrile butadiene rubber/chloroprene rubber (NBR/CR) acoustic composites were extensively studied and prepared. According to the orthogonal test table L25 (56), 25 groups of samples were prepared by using a low-temperature one-time rubber mixing process. With tensile strength, average transmission loss, and damping peak as indexes, the influence degree of different factors and levels on the properties of acoustic composites was quantitatively discussed and analyzed. The matrix weight analysis was employed to optimize the material formula of rubber composites, and the corresponding influence weight was given. Results showed that the acoustic composite with blending ratio of 70/30 for NBR/CR matrix had preferable mechanical and acoustic properties; adding mica powder (MP) and montmorillonite (MMT) in matrix contributed to improve all above three indexes owing to their specific lamellar structures; hollow glass beads (HGB) had a positive influence on improving acoustic property due to its hollow microcavities, however, it had a negative impact on damping property because of the smooth spherical surfaces. Accordingly, the optimal formulation was found to be NBR/CR blending ratio of 70/30, MP of 10 phr (per hundred rubber), HGB of 4 phr, and MMT of 10 phr.

Isosorbide-5-mononitrate (5-ISMN), an organic nitrate vasodilator, has been widely used worldwide to prevent angina pectoris for more than two decades. A simple and sensitive high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed and validated for the determination of 5-ISMN in human plasma. 13C6-5-ISMN is an internal standard, and 5-ISMN was extracted from human plasma (50 µL) with ethyl acetate (200 µL) by a simple liquid-liquid extraction method. The chromatographic separation was carried out on LC-20A (Shimadzu, Japan) using an analytical column ZORBAX XDB-C18 (4.6 × 50 mm, 5 µm), coupled with API 4000 tandem mass spectrometers in a multiple reaction monitoring (MRM) mode. The mobile phase was composed of acetonitrile (organic phase A) and 2 mM ammonium acetate in water (aqueous phase B) with an isocratic elution of A/B = 90 : 10 (v/v). The total run time was 3.5 min with a small injection volume (5 µL). This method was fully validated in every aspect of selectivity, linearity, accuracy, precision, matrix effect, extraction recovery, and different stabilities. It was proved that the calibration standards within the 5.00–1000 ng/mL concentration range were linear. The lower limit of quantification was 5.00 ng/mL for 5-ISMN. The intrabatch and interbatch accuracy (RE) ranged from −8.8% to 7.1% with precision between 2.4% and 6.6%. The mean values of 5-ISMN extraction recovery and matrix effect were 87.0% and 102.0%, respectively. The fully validated method was successfully applied for a bioequivalence clinical trial of oral 20 mg 5-ISMN tablets in healthy Chinese subjects.

To solve the problems of low precision and molding efficiency of 3D printing technology at present, the concept of “3D copying” intelligent manufacturing is put forward for the first time considering the important demands and background knowledge of intelligent manufacturing, which integrates the research works of the author's team in the field of precision injection molding and melt differential 3D printing technology of polymer. Supported by the National Natural Science Foundation of China and the key R & D projects, the core principle and technical route of 3D copying technology have been preliminarily explored. Three key aspects of the scientific and technical issues are discussed, namely, target product's virtual design or 3D modeling, 3D printing of mould, intelligent injection molding. 3D copying technology can realize the rapid, high precision and large quantity replication of samples. It is expected to become a new trend of modern manufacturing intelligent development, and has a broad application prospect. Keywords: Polymer, 3D printing, 3D copying, Molding, Intelligent manufacturing

In the present work, the ductile formation mechanism of a newly proposed torsion configuration has been investigated. One of the unique attributes of this paper is the first-time disclosure of the design and fabrication of a novel prototype screw with torsional flow character validating the orthogonal test model experimentally. The torsional spiral flow patterns that occurred in the torsion channel cause a ductile deformation of polymer in the form of a spiral, which in turn enhances the radial convection, achieving an effective mass transfer of material from the top region to the bottom region and vice versa. Furthermore, the characteristic parameters of torsion configuration have a significant influence on the plasticizing and melting capability of polymer. By range analysis and weight matrix analysis, the best factor and level combination was obtained. Results indicated that the aspect ratio of the torsion channel is almost equal to 1, and the plasticizing and melting capability of polymer is optimal. This novel design innovation offers a paradigm shift in the energy-efficient plasticization of polymer compounds.

Proton pump inhibitors (PPIs) are the mainstay for treatment of acid-related diseases. This study developed a mechanism-based pharmacokinetic (PK) and pharmacodynamics (PD) model with ilaprazole as case drug, so as to support and accelerate the development of novel PPIs. The model was established and verified using the PK and PD data from 26 subjects receiving 5 to 30 mg of ilaprazole and 22 subjects receiving the loading dose of ilaprazole 20 mg followed by 10 mg once daily for 2 days. The nonlinear mixed-effects modeling approach was performed for the PK/PD model. A two-compartment model with linear elimination and covariates (body weight and gender) described the observed data well. The relationship between plasma concentrations of ilaprazole and gastric acid pH was well quantified with individual variability, in which the synthesis and degradation of H+/K+-ATPase, the food effect, the circular rhythms of gastric acid secretion, and the irreversible inhibition of H+/K+-ATPase by ilaprazole were integrated. This PK/PD model well predicted the PK and PD profile of ilaprazole in healthy subjects and patients with duodenal ulcers receiving wide range dose regimens. The mechanism-based PK/PD model provided a potential strategy to accelerate the development of novel PPIs by waiving the unnecessary clinical trials.

In this study, a simple method was adopted for the synthesis of MnO@C nanocomposites by combining in-situ reduction and carbonization of the Mn3O4 precursor. The carbon content, which was controlled by altering the annealing time in the C2H2/Ar atmosphere, was proved to have great influences on the electrochemical performances of the samples. The relationships between the carbon contents and electrochemical performances of the samples were systematically investigated using the cyclic voltammetry (CV) as well as the electrochemical impedance spectroscopy (EIS) method. The results clearly indicated that the carbon content could influence the electrochemical performances of the samples by altering the Li+ diffusion rate, electrical conductivity, polarization, and the electrochemical mechanism. When being used as the anode materials in lithium-ion batteries, the capacity retention rate of the resulting MnO@C after 300 cycles could reach 94% (593 mAh g−1, the specific energy of 182 mWh g−1) under a current density of 1.0 A g−1 (1.32 C charge/discharge rate). Meanwhile, this method could be easily scaled up, making the rational design and large-scale application of MnO@C possible.

A novel torsion screw has been proposed to resolve the inadequate control of mass transfer and the thermal management of two component polymer blends and their carbon fiber composites. The novel torsional screw distinctly introduced radial flow in the torsion screw channel, which is a significant improvement over the flow pattern developed by the conventional screw. The heat transfer and mixing behavior of melt mixtures are enhanced by adapting screws with torsion elements compared with the traditional screw elements. Heat transfer efficacy in the polypropylene–polystyrene bi-phasic extrusion process improved with the increase in torsion element numbers. An increased number of newly designed torsional elements also improved the dispersion of minor phase in bi-phase polypropylene–polystyrene composition and their carbon fiber composites. The unique flow pattern induced by the torsion elements shows a synergistic effect on the melt-phase mass flow and the thermal flow field facilitating phase-to-phase thermal and molecular mobility and enhanced fiber orientation, crystallinity and mechanical properties of composite made from recycled carbon fiber/polypropylene. Microtomographs of recycled carbon fiber demonstrated the extraordinary ability of a torsion screw element to orient carbon fiber in both axial and radial directions.

Among the transition metal oxides, the Mn3O4 nanostructure possesses high theoretical specific capacity and lower operating voltage. However, the low electrical conductivity of Mn3O4 decreases its specific capacity and restricts its application in the energy conversion and energy storage. In this work, well-shaped, octahedron-like Mn3O4 nanocrystals were prepared by one-step hydrothermal reduction method. Field emission scanning electron microscope, energy dispersive spectrometer, X-ray diffractometer, X-ray photoelectron spectrometer, high resolution transmission electron microscopy, and Fourier transformation infrared spectrometer were applied to characterize the morphology, the structure, and the composition of formed product. The growth mechanism of Mn3O4 nano-octahedron was studied. Cyclic voltammograms, galvanostatic charge−discharge, electrochemical impedance spectroscopy, and rate performance were used to study the electrochemical properties of obtained samples. The experimental results indicate that the component of initial reactants can influence the morphology and composition of the formed manganese oxide. At the current density of 1.0 A g−1, the discharge specific capacity of as-prepared Mn3O4 nano-octahedrons maintains at about 450 mAh g−1 after 300 cycles. This work proves that the formed Mn3O4 nano-octahedrons possess an excellent reversibility and display promising electrochemical properties for the preparation of lithium-ion batteries.

With the continuous increase in the production of electronic devices, large amounts of electronic waste (E-waste) are routinely being discarded into the environment. This causes serious environmental and ecological problems because of the non-degradable polymers, released hazardous chemicals, and toxic heavy metals. The appearance of biodegradable polymers, which can be degraded or dissolved into the surrounding environment with no pollution, is promising for effectively relieving the environmental burden. Additionally, biodegradable polymers are usually biocompatible, which enables electronics to be used in implantable biomedical applications. However, for some specific application requirements, such as flexibility, electric conductivity, dielectric property, gas and water vapor barrier, most biodegradable polymers are inadequate. Recent research has focused on the preparation of nanocomposites by incorporating nanofillers into biopolymers, so as to endow them with functional characteristics, while simultaneously maintaining effective biodegradability and biocompatibility. As such, bionanocomposites have broad application prospects in electronic devices. In this paper, emergent biodegradable and biocompatible polymers used as insulators or (semi)conductors are first reviewed, followed by biodegradable and biocompatible nanocomposites applied in electronics as substrates, (semi)conductors and dielectrics, as well as electronic packaging, which is highlighted with specific examples. To finish, future directions of the biodegradable and biocompatible nanocomposites, as well as the challenges, that must be overcome are discussed.