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The Palaeocene-Eocene (66–41 Ma) hosts the most intense stage of extensive magmatism in the Gangdese belt of southern Tibet. However, the magma sources and tectonic setting of this magmatic belt have been a matter of discussion for decades. In this study, we conducted zircon geochronological and geochemical studies on Eocene gabbroic rocks and granitic rocks from the Jiacha area in the eastern Gangdese belt. Laser ablation-ICP-MS zircon U–Pb dating suggests almost synchronous crystallization ages of 50–47 Ma for both rock types. Geochemically, the gabbroic rocks have low total rare earth elements and high positive zircon eHf(t) values (from +8.4 to +15.0), indicating that the parental magma was derived from an isotopically depleted mantle. The granitic rocks are magnesian calc-alkalic to calcic granites that are characterized by variable zircon eHf(t) values (from +3.0 to +10.8), indicating that the magmas were generated by differentiation of a mantle-derived magma with variable contributions from ancient crustal materials. Furthermore, an enlarged database of 66–41 Ma plutonic rocks and coexisting Linzizong volcanic rocks reveals an evolutionary trend from mafic to silicic rocks. The zircon Hf and Nd isotopic compositions become more evolved with increasing whole-rock SiO2. The whole-rock and isotope geochemistry of the 66–41 Ma plutonic rocks and the Linzizong volcanic rocks indicate an origin and evolution of these rocks in an active continental margin setting. Therefore, we argue that the Gangdese belt was associated with the subduction of the Neo-Tethyan Oceanic plate throughout the Early Eocene, thereby implying that the initial India-Asia collision occurred after ~ 41 Ma.

Lithium metal batteries (LMBs) possess outstanding theoretical energy density and have attracted widespread attention as the next generation of energy storage devices for various crucial applications. However, the commercialization of LMBs has to simultaneously overcome numerous challenges, such as inferior Coulombic efficiency and cycling performance, high self-discharge, and complicated interfacial reactions. It has traditionally been an enormous challenge about the uniform deposition of lithium on the surface of current collector to relieve the formation of lithium dendrites. In this study, a novel efficient strategy of plating uniform lithiophilic polythiophene derivatives substrates on Cu foils was developed and the nucleation mechanism of Li ions on polythiophene derivatives substrates was further explored. We first explored the interaction between polythiophene derivatives substrates and Li ions by first-principles calculations, and found shorter side chains of polythiophene derivatives can enhance the adsorption energy and promote the diffusion rate of Li ions. Polythiophene derivatives substrates have a large number of dispersive lipophilic sites and Li ions diffusion channels in the main chain, which can effectively regulate the nucleation and growth stages of Li ions deposition. We further found polythiophene derivatives with different side chains can induce the electrodeposition of Li ions with different morphology, while the polythiophene derivatives with the shortest side chains can contribute to the most excellent cycle efficiency, resulting in a uniform lithium deposition with less lithium dendritic growth experimentally.

Several mesostructured cellular foams (MCFs) were prepared and modified for NO adsorption. TMB, NH4F and n-heptane were used as swelling agents, and APTES was used as the modified agent. The morphological structure, chemical composition, thermostability were tested to study the effects of the preparation process on the characterizations of materials. NO adsorption ability of the materials were studied and discussed. NH4F and n-heptane had better pore swelling effects compared to TMB, however adding TMB together with NH4F and n-heptane could not enlarge the pore structure further. The MCFs materials could keep steady below 800 °C, but after grafting APTES on the surface of the materials, the thermogravimetric curve of materials began to decrease at 300 °C. The materials using NH4F and n-heptane as the swelling agents, and modified by APTES had better NO adsorption ability, and the selectivity of the materials were decided by the molecular polarity of the adsorbates. After the modification, the hydrophobic effect of the samples could increase because of the alkyl groups in APTES. The adsorption capacity of the materials could keep steady for ten times without the coexisting component, H2O, CO2 and SO2 all had negative effects on the regeneration of the materials.

In the present study, an industrially viable ceramics fabrication way based on solid-state reaction method–semi-solution method was used to improve the dielectric and ferroelectric properties of acceptor-donor co-doped BaTiO3 ceramics. Unlike the conventional solid-state reaction method, additives in the semi-solution method were introduced in the form of the aqueous solution rather than oxide powders. Experiment results show that higher peak dielectric constant e m a x (140–150%), larger maximum polarization P m a x (24 μC cm−2), and less apparent aging phenomena were achieved by the semi-solution method. A comprehensive microscopic analysis was carried out to explore the origin of property enhancement. Results show that enhanced properties could be ascribed to the higher level of compositional homogeneity and lower content of oxygen vacancies. This study provides a new method to control aging phenomena and achieve property enhancement in acceptor-donor co-doped ceramics. Moreover, this simple and cost-effective method may also find its application in other extensive-doped ceramics.

Developing efficient, stable, and cheap photocatalysts for H2 production has aroused great interest among researchers. Herein, noble-metal-free ZnO/SrTiO3 composite photocatalysts have been successfully prepared by hydrothermal method. X-ray diffraction, field-emission scanning electron microscopy, high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, ultraviolet–visible diffusion spectroscopy, and photoluminescence spectroscopy are used to characterize the obtained samples. The photocatalytic water splitting for H2 production by ZnO/SrTiO3 has been studied under simulated sunlight irradiation by using triethanolamine as a sacrificial agent and Eosin Y (EY) dye as a sensitizer. The orthogonal experiments are designed to optimize the photocatalytic reaction conditions for practical purposes. The influencing extents and trends of the factors have been investigated, including the catalyst composition and dosage, pH value of the solution, triethanolamine, and EY addition. Under the optimum conditions, the H2 production rate with ZnO/SrTiO3 is up to 16006.12 μmol g−1 h−1. The excellent performance of ZnO/SrTiO3 is attributed to the formation of a step-scheme (S-scheme) heterojunction, which promotes the separation of photocarriers and reduces their recombination probability.

The dramatic increase of microbial resistances against conventional available antibiotics is a huge challenge to the effective treatment of infectious disease and thus becoming a daunting global threat of major concern, which necessitates the development of innovative therapeutics. Nanomaterial-based antimicrobial strategies have emerged as novel and promising tools to combat lethal bacteria and recalcitrant biofilm, featuring the abilities to evade existing drug resistance-related mechanisms. In this review, recent advances in “state-of-the-art” nanosystems which acting either as inherent therapeutics or nanocarriers for the precise delivery of antibiotics, are comprehensively summarized. Those nanosystems can effectively accumulate at the infectious sites, achieve multifunctional synergistic antibacterial efficacy, and provide controlled release of antibiotics in response to endogenous or exogenous stimulus (e.g., low pH, enzymes, or illumination). Especially, the nanoplatform that integrated with photothermal/photodynamic therapy (PTT/PDT) can enhance the bacterial destruction and biofilm penetration or ablation. In addition, nanoparticle-based approaches with enzymatically promoting bacterial killing, anti-virulence, and other mechanisms were also involved. Overall, this review provides crucial insights into the recent progress and remaining limitations of various antimicrobial nanotherapeutic strategies, and enlightens the further developments in this field simultaneously, which eventually benefiting public health.

Selenium (Se) is one of the toxic trace elements in flue gas emitted from coal-fired power plants. A method for oxidation and absorption of selenium dioxide (SeO2) by hydrogen peroxide (H2O2) and sodium chlorite (NaClO2) in a calcium-based slurry is proposed, in which hydrated lime (Ca(OH)2) and calcium carbonate (CaCO3) were selected to be absorbents, and H2O2 and NaClO2 were used to oxidize SeO2 and selenite ion to selenate ion to reduce their toxicities. The effects of reaction temperature, H2O2 and NaClO2 concentrations, solution pH, and SeO2 concentration were investigated, from which the optimal reaction conditions were established. The results indicated that the oxidation efficiency was affected significantly by the solution pH, and H2O2 and NaClO2 concentrations. The oxidation efficiency of SeO2 and selenite ion to selenate ion was below 40% using H2O2 and that increased to 92% with NaClO2 at the optimal conditions. For removal, Ca(OH)2 and CaCO3 slurries were used as absorbents and the efficiencies were affected by the slurry temperature. Oxidation behavior and mechanism were analyzed based on the characterization of removal products using hydride generation-atomic fluorescence spectrometry and X-ray photoelectron spectroscopy. SeO2 and selenite ion can be oxidized to selenate ion, which is less toxic, by active species such as hydroxyl radicals (HO·) and chlorine dioxide (ClO2), which are released during the decomposed processes of H2O2 and NaClO2 in acid conditions.

Endothelial cilia are microtubule-based hair-like protrusions in the lumen of blood vessels that function as fluid mechanosensors to regulate vascular hemodynamics. However, the functions of endothelial cilia in vascular development remain controversial. In this study, depletion of several key proteins responsible for ciliogenesis allows us to identify a cilium-independent role for intraflagellar transport 88 (IFT88) in mammalian angiogenesis. Disruption of primary cilia by heat shock does not affect the angiogenic process. However, depletion of IFT88 significantly inhibits angiogenesis both in vitro and in vivo. IFT88 mediates angiogenesis by regulating the migration, polarization, proliferation, and oriented division of vascular endothelial cells. Further mechanistic studies demonstrate that IFT88 interacts with γ-tubulin and microtubule plus-end tracking proteins and promotes microtubule stability. Our findings indicate that IFT88 regulates angiogenesis through its actions in microtubule-based cellular processes, independent of its role in ciliogenesis.

Spatiotemporal variations of industrial carbon emissions (IE) must be scientifically understood, which will be helpful to formulate reasonable emission reduction strategies. Given that spatial distribution of IE is irrelevant to space agents commonly used (such as population and nighttime light), estimation and spatialization methods for total carbon dioxide (CO2) emissions are not entirely suitable for IE. Therefore, this paper used greenhouse gases observing satellite level 4A product to estimate IE at the city level and used industrial land density to obtain the distribution of IE within the administrative districts. Sectoral emission inventories of 182 cities and a mosaic Asian anthropogenic emission inventory named MIX were used to verify the results. Then, spatiotemporal variation characteristics of China's IE were analyzed from multiple levels. Results showed that (1) the mean relative error of estimation results was 56.11%, among which 62 cities had relative error of less than 30%. Gridded IE in this paper had high consistency with MIX. (2) Cities with high IE experienced rapid growth from 2009 to 2012, followed by slower growth from 2012 to 2017. (3) Centroid of significant cold and hot spots moved to the southeast and northwest, respectively. Most cities with high annual IE growth had relatively low emission efficiency, mainly located in Inner Mongolia and Xinjiang. Aggregation of medium and high IE grids may represent high emission efficiency. Significant differences still exist between cities in IE, and sustainable development strategies should be formulated according to local conditions. Regions with high annual growth or low emission efficiency are the key to achieving IE reduction targets in future.

The phthalate concentrations in dust from undergraduate dormitories, classrooms, and homes in Beijing, China, were measured in April 2017. We analyzed the characteristics of phthalates in dust from three environments. In addition, we estimated the daily intake of phthalates via three pathways using Monte Carlo simulations. The detection frequency of eight phthalates in dust ranges from 74.5 to 100%. Di (2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DnBP), and di-isobutyl phthalate (DiBP) are the most abundant phthalates. The median proportion of DEHP in dust is the highest, ranging from 67.1 to 72.9%. The PMF results indicated that two, four, and three types of phthalate sources exist in home, dormitory, and classroom, respectively. The differences in the phthalate concentrations between sunny and shaded rooms and urban and suburban classrooms are insignificant, whereas that between male and female dormitories is significant. The total daily intake of DEHP, DnBP, and DiBP ranges from 97.3 to 336 ng/ (kg·day). The oral intake for DEHP in classrooms and the dermal intake of DnBP and DiBP in homes are the highest. The carcinogenic risk of DEHP to university students is the highest in classrooms and the total carcinogenic risk of the three environments is 4.70 × 10-6.

Bisphenol A (BPA) is a widely used raw material that can be detected both in the environment and in the human body. Due to its estrogen-like effects, wide concerns have been raised about the potential role of BPA in the initiation and development of hormone-dependent cancers. Ovarian cancer is the most common reproductive system cancer and has a high mortality rate in women. Despite recent investigations into BPA's carcinogenic effects, studies on its role in ovarian cancer development remain limited. In this study, we aimed to assess the effect of BPA at various environmentally relevant concentrations on proliferation and metastasis of ovarian cancer cells. We discovered that BPA can stimulate proliferation of OVCAR-3 ovarian cancer cells after exposure for up to 5 days. Strikingly, BPA enhanced ovarian cancer cell migration, invasion, and adhesion (to vascular endothelial cells) through upregulation of matrix metalloproteinase-2 (MMP-2), MMP-9, and intercellular cell adhesion molecule-1 (IMAC-1). The stimulatory effects of BPA on cancer cell proliferation and metastasis were reversed by treatment with an ERα inhibitor, but not by treatment with an ERβ inhibitor. Together, these results suggest that BPA induces proliferation and metastasis of ovarian cancer cells through ERα signaling pathways. This study provides new insights into the carcinogenic effects of BPA with regard to ovarian cancer.

Breast cancer susceptibility gene 1 (BRCA1) is an important tumor suppressor gene in the human which associated with a variety of tumor suppressor genes to inhibit the growth of malignant tumors. Breast cancer is closely related to BRCA1 mutations in humans. Four BRCA1 (856-871) mutants were screened that can interact well with RAD51 (158-180) using computer to simulate mutations at Y 856, R 866 and Q 867. These mutants were synthesized by using Fmoc solid-phase synthesis, and purified by liquid chromatography. According to the results of fluorescence spectroscopy, R866W has the strongest binding ability for the above peptides and RAD51 (158-180). Based on the circular dichroism spectrum results, the sequence of the interaction ability of the above peptides on the secondary structure of RAD51 (158-180) is Y856P, Q867C > Y856P, R866W ≈ R866W > Y856P > BRCA1. All the spectral results show that R866W have the strongest interaction ability with RAD51(158-180).

Exploration of deep mineralization, particularly where the mineralization of interest is covered by a conductive overburden, is still a challenge for the conventional transient electromagnetic (TEM) method, which measures TEM response using induction coils as the sensor. However, sensors such as fluxgate and superconductive quantum interfere device (SQUID) magnetometers can measure the B-field directly, which can provide more reliable deep information for mineralization exploration. In this paper, we report on the research and development of our newly developed high-temperature superconductor (HTS) SQUID magnetometer, which is cooled by liquid nitrogen at 77 K, and its application in TEM measurement for deep exploration in a gold deposit in China. This improved SQUID magnetometer version has a good performance with noise (60 fT/ $$\sqrt {{\rm{Hz}}} $$ ), slew rate (0.8 mT/S), dynamic range (100 dB), sensitivity (6.25 mV/nT), and bandwidth (DC-20 kHz). To find deep and peripheral ore in the Baiyun gold deposit located in Liaoning Province, NE China, both the SQUID magnetometer and induction coil were used for TEM data acquisition. Results show that TEM can detect the distribution of local strata and the faults contained within them. Results also indicate that the SQUID magnetometer has superior response performance for response over geological targets with slower decay time when compared to the induction coil signals. The SQUID magnetometer is more sensitive at observing the induced-polarization effect which is closely related to the ore-controlling faults.

Kinesin-1 is a motor protein moving along a microtubule with its two identical motor heads dimerized by two neck linkers and a coiled-coil stalk. When both motor heads bind the microtubule, an internal strain is built up between the two heads, which is indispensable to ensure proper coordination of the two motor heads during kinesin-1's mechanochemical cycle. The internal strain forms a tensile force along the neck linker that tends to unwind the neck coiled coil (NCC). Experiments showed that the kinesin-1's NCC has a high antiunwinding ability compared with conventional coiled coils, which was mainly attributed to the enhanced hydrophobic pressure arising from the unconventional sequence of kinesin-1's NCC. However, hydrophobic pressure cannot provide the shearing force which is needed to balance the tensile force on the interface between two helices. To find out the true origin of the mechanical stability of kinesin-1's NCC, we perform a novel and detailed mechanical analysis for the system based on molecular dynamics simulation at an atomic level. We find that the needed shearing force is provided by a buckle structure formed by two tyrosines which form effective steric hindrance in the presence of tensile forces. The tensile force is balanced by the tensile direction component of the contact force between the two tyrosines which forms the shearing force. The hydrophobic pressure balances the other component of the contact force perpendicular to the tensile direction. The antiunwinding strength of NCC is defined by the maximum shearing force, which is finally determined by the hydrophobic pressure. Kinesin-1 uses residues with plane side chains, tryptophans and tyrosines, to form the hydrophobic center and to shorten the interhelix distance so that a high antiunwinding strength is obtained. The special design of NCC ensures exquisite cooperation of steric hindrance and hydrophobic pressure that results in the surprising mechanical stability of NCC.

The lateral roots of Aconitum carmichaelii, known in Chinese as fuzi, are officially recognized as a materia medica in the Chinese Pharmacopoeia and used culinarily to prepare herbal soups. A strategy combining UPLC-qToF-MS analysis of A. carmichaelii and its intraspecies and interspecies chemometrics study was developed to examine the distribution of Aconitum marker metabolites. Four diterpenoid alkaloids were recognized to be important markers in fuzi, and another 15 markers were identified to differentiate A. carmichaelii from adulterant species. The detected fuzi markers, mesaconitine (47) and hypaconitine (51), are known to be the principal toxins in this herb, while fuziline (6) and benzoylmesaconine (25) are associated with its medicinal properties. Additional marker compounds have been detected in other Aconitum species that are useful for identifying adulteration. This study provides a useful resource for detecting traditional Chinese medicine (TCM) adulterants and assisting in the quality control of botanical products in TCM and beyond.

Insightful understanding of the light driven CO2 reduction reaction (CO2RR) mechanism on gold nanoparticles is one of the important issues in the plasmon mediated photocatalytic study. Herein, time-dependent density functional theory and reduced two-state model are adopted to investigate the photoinduced charge transfer in interfaces. According to the excitation energy and orbital coupling, the light driven mechanism of CO2RR on gold nanoparticles can be described as follows: the light induces electron excitation and then transfers to the physisorbed CO2, and CO2 can relax to a bent structure adsorbed on gold nanoparticles, and the adsorbed C-O bonds are dissociated finally. Moreover, our calculated results demonstrate that the s, p, and d electron excitations of gold nanoparticles are the major contribution for the CO2 adsorption and the C-O dissociation process, respectively. This work would promote the understanding of the light driven electron transfer and photocatalytic CO2RR on the noble metal.

Multifunctional and flexible intelligent devices are urgently needed to solve increasingly serious environmental effects on the human body. However, rendering devices with multifunctionality without sacrificing their innate flexibility and properties remains a huge challenge. Herein, a facile and efficient strategy involving Ag precursor reduction followed by a spraying technique was employed to fabricate a multifunctional and ultra-stretchable fibrous film via the incorporation of an electrospun thermoplastic polyurethane (TPU) fibrous film, biocompatible polydopamine (PDA), highly conductive Ag nanoparticles (AgNPs) and Ti3C2Tx MXene nanosheets. Specifically, PDA protected AgNPs from oxidation and enhanced the bond between AgNPs and TPU, and MXene was used to promote the electromagnetic interference shielding (EMI) and strain sensing performance. The optimized TPU/PDA/AgNP/MXene fibrous film (TAMF) exhibited an ultra-high electrical conductivity of 95 238 S m−1, outstanding EMI shielding efficiency (EMI SE) of 108.8 dB and high specific shielding effectiveness up to 12 342.8 dB cm2 g−1 with a thickness of 150 μm in the X-band. The flexible fibrous mat also possessed excellent Joule heating capability (up to 80 °C at a voltage of 1 V), excellent mechanosensation ability with a low detection limit of 0.1% strain, a high gauge factor of 7853, wide sensing range of 200% strain, and satisfactory flexibility, porosity and breathability, enabling its fascinating multifunctional application in wearable electromagnetic wave protection, electrical therapy and human–machine interaction.

In this work, we present the performance improved InGaZnO thin film transistors by inserting low temperature processed 10 nm thick SiOCH buffer layers between SiNx insulator and InGaZnO channel layer. The influences of oxygen flow rate during the deposition of SiOCH buffer layer have been intensively investigated. Basing on the analysis of hall effect measurement and Fourier transform infrared spectrum, the SiOCH buffer layer can effectively increase the carrier concentration of the channel layer by the hydrogen doping due to re-sputtering and diffusion effect. The InGaZnO thin film transistor with buffer layer exhibits an enhanced performance with mobility of 13.09 cm2/vs, threshold voltage of −0.55 V and Ion/Ioff over 106.

Covering: up to 1 October 2020 Solanum steroidal glycoalkaloids (SGA), characterized by nitrogenous steroidal aglycone and glycoside residues, mainly occur in the Solanum species, including economically important edible plants such as potato, tomato, and eggplant. To date, 107 SGA assigned to six total skeletons have been identified from Solanum plants. SGA have unique structures and display significant pharmacological activities such as cytotoxic, antimicrobial, anticholesterol, and some are well-known poisons. The biosynthesis pathway, transcriptional regulation, and the evolution of SGA are also examined in detail. This report updates the chemical knowledge of the naturally occurring SGA from Solanum species, thereby providing an in-depth analysis of their diversity, biological activities, and biosynthesis.

Occlusion of blood vessel caused by thrombus is the major pathogenesis of various catastrophic cardiovascular diseases. Thrombus can be prevented or treated by antithrombotic drugs. However, free antithrombotic drugs often have relatively low therapeutic efficacy due to a number of limitations such as short half-life, unexpected bleeding complications, low thrombus targeting capability, and negligible hydrogen peroxide (H(2)O(2))-scavenging ability. Inspired by the abundance of H(2)O(2) and the active thrombus-targeting property of platelets, a H(2)O(2)-responsive platelet membrane-cloaked argatroban-loaded polymeric nanoparticle (PNP(Arg)) was developed for thrombus therapy. Poly(vanillyl alcohol-co-oxalate) (PVAX), a H(2)O(2)-degradable polymer, was synthesized to form an argatroban-loaded nanocore, which was further coated with platelet membrane. The PNP(Arg) can effectively target the blood clots due to the thrombus-homing property of the cloaked platelet membrane, and subsequently exert combined H(2)O(2)-scavenging effect via the H(2)O(2)-degradable nanocarrier polymer and antithrombotic effect via argatroban, the released payload. The PNP(Arg) effectively scavenged H(2)O(2) and protected cells from H(2)O(2)-induced cellular injury in RAW 264.7 cells and HUVECs. The PNP(Arg) rapidly targeted the thrombosed vessels and remarkably suppressed thrombus formation, and the levels of H(2)O(2) and inflammatory cytokine in the ferric chloride-induced carotid arterial thrombosis mouse model. Safety assessment indicated good biocompatibility of the PNP(Arg). Taken together, the biomimetic PNP(Arg) offers multifunctionalities including thrombus-targeting, antioxidation, and H(2)O(2)-stimulated antithrombotic action, thereby making it a promising therapeutic nanomedicine for thrombosis diseases.

Despite remarkable clinical achievements, camptothecin (CPT) still suffers from poor solubility and severe toxicity. Therefore, it is necessary to redevelop CPT derivatives as supplementary antitumor agents with good water solubility and small side effects. In this work, 27 camptothecin derivatives were synthesized and screened for their cytotoxicity against A549 (lung) and HCT-116 (colon) cancer cell lines. Among them, compound B7, 7-ethyl-10-(2-oxo-2-(4-methylpiperidin-1-yl)ethoxy)camptothecin,was demonstrated in vitro to be a more potent antitumor agent than SN-38 by comparison of their inhibitory activities against cell proliferation and colony formation and interference effect on process of cell cycle and cell apoptosis. Additionally, a molecular docking model revealed that B7 can interact with the topoisomerase I-DNA complex, and that the solubility of B7 reached 5.73 μg/mL in water. Moreover, B7 significantly inhibited tumor growth in an A549 xenograft model at dosages of 0.4 and 2.0 mg/kg, and exhibited minimum lethal doses comparable to those of irinotecan. These results indicated that B7, with improved solubility, enhanced activity and acceptable acute toxicity, can be used as a lead compound for the development of novel anticancer agents.

A novel Pd/Cu-cocatalyzed isocyanide-insertion cyclization of indoles and hydrolysis of enamines has been developed for the construction of indolo[1,2-a]quinoxalinones. A secondary amine group on the N-phenylindole skeleton acts as an important directing groups that participates in activation of the C(2)-position of the indole and the subsequent isocyanide-insertion cyclization. The fragile generated enamine bond is easily hydrolyzed by the acid medium to give the corresponding quinoxalinone skeleton. This regioselective and high-yielding transformation, which avoids the use of hazardous CO gas, might be extendable to syntheses of natural polycyclic products.

For continuous or spiral windings which feature multiple continuously transposed conductors (CTC) wound in parallel, the transposition structure is commonly used to suppress circulation between conductors. This introduces a local asymmetry in transformer windings. Fault analyses have shown that building an asymmetric structure in transformers increases deformation risk in these windings. Researchers have yet to fully investigate this asymmetric structure. This study was conducted to observe the influence of transposition structure in a 110 kV transformer. The conductor’s relative position forms three patterns during the transposition process; two parameters are established to describe the position-changing process. A finite-element method (FEM) model is built to investigate the magnetic field and electromagnetic force distributions. The results indicate that the transposition structure distorts the magnetic field distribution. The maximum distortion factor of the axial component of magnetic flux density ( $B_{\mathrm {z}}$ ) along the axial direction caused by the transposition structure is 14.6%. The transposition structure only changes the radial change slope of $B_{\mathrm {z}}$ . The gap caused by the transposition process aggravates imbalance in the ampere-turns distribution, increasing the amplitude of the radial component of magnetic flux density ( $B_{\mathrm {r}}$ ) at the middle height of the transformer low voltage (LV) winding. The maximum amplitude of $B_{\mathrm {r}}$ at the transposition structure increases by 513%. The Lorentz force over the CTCs remains constant from before to after the transposition process, though its linear density over the CTCs is unevenly distributed throughout. The axial component $F_{\mathrm {z}}$ varies from −31 to 10 kN/m, while the radial component $F_{\mathrm {r}}$ varies from −146 to −51 kN/m. The results show that the initial stage of the CTC height rising segment is a weak point and should be strengthened in the manufacturing process.

The hierarchical stochastic Schrodinger equations (HSSE) are a kind of numerically exact wavefunction-based approaches suitable for the quantum dynamics simulations in a relatively large system coupled to a bosonic bath. Starting from the influence-functional description of open quantum systems, this review outlines the general theoretical framework of HSSEs and their concrete forms in different situations. The applicability and efficiency of HSSEs are exemplified by the simulations of ultrafast excitation energy transfer processes in large-scale systems.

In the paper, the effect of time-periodic gravity modulation with trigonometric sine, triangular, and square waves-forms on Rayleigh Benard convection in water-alumina nanoliquids and water-alumina-copper hybrid nanoliqiuds is studied by using a single-phase model. Using a perturbation method, linear stability analysis is performed for all the three wave-forms. A generalized Lorenz model that has the influence of nanoliquids and modulation incorporated in it is derived using a truncated Fourier series representation. The Lorenz model is then transformed into a Ginzburg-Landau model using the method of multiscales, and the solution is used to study heat transport. For trigonometric sine, triangular and square wave-forms of modulations comparison are made on their effect on the onset of convection and the heat transport. The linear stability analysis reveals that the critical Rayleigh number obtained in the case of a triangular wave-form is less compared to the value obtained in the cases of trigonometric sine and square wave-forms. This leads to an enhanced heat transfer situation in the case of triangular wave-form compared to that in the other two wave-forms. It is also found that such an enhancement in heat transport increases with amplitude and decreases with the modulation frequency. Thus, the modulation is found to be a regulating mechanism on heat transport. Further, it is observed that water-alumina-copper facilitates maximum heat transport compared to that by water-alumina and water, leading to the conclusion that hybrid nanoliquids facilitate enhanced heat transport compared to that by mono nanoliquids.

Recently, asteroid exploration becomes an important branch of human’s deep space activities. In this paper, a piecewise linear optimal orbital maneuver strategy is designed for a spacecraft soft landing on irregular-shaped asteroids. First, the space around an irregular asteroid is converted into several grid units, and the gravitational field of the asteroid is linearly fitted in each unit. Then, the soft-landing orbital maneuver strategy design problem is formulated as a piecewise linear optimal problem, and further transferred into a family of two-point boundary value problems, which can be solved using collocation method. Finally, a corresponding algorithm is developed to obtain the piecewise linear optimal maneuver strategy, which is proved to be able to achieve the soft-landing mission well. Simulation results show that the error of the model linearization is small enough, while the calculation efficiency is remarkably improved, and the robustness of maneuver strategy is also improved.

Control-released aromatic-nanocapsules/cotton fabrics with good wash durability and long-lasting fragrance release capability have been fabricated without adhesives via electrostatic-adsorption and...

Di(2-ethylhexyl) phthalate (DEHP) is a widespread pollutant that badly affects animals and human health. Lycopene (LYC) has been used as a dietary supplement that has effective antioxidant and antiobesity functions. The present goal was to understand the molecular mechanisms of LYC preventing DEHP-induced lipid metabolism of the liver. The mice were intragastrically administered with LYC (5 mg/kg) and/or DEHP (500 mg/kg or 1000 mg/kg). Here, we found that LYC attenuated DEHP-caused hepatic histopathological lesions including steatosis. Hematological and biochemical analyses revealed that LYC ameliorated DEHP-caused liver function and lipid metabolism disorders. DEHP caused lipid metabolism disorders via activating the peroxisome proliferator activated receptor α/γ (PPARα/γ) signal transducer and Farnesoid X receptor (FXR)/liver X receptor (LXR) signaling pathway. As a major regulator of lipid metabolism, hypoxia-inducible factor-1α (HIF-1α) system was elevated with increased fatty degeneration under DEHP exposure. However, LYC could decrease the levels of HIF-1α/PPARα/PPARγ/FXR/LXR signaling pathway-related factors. Our research indicated that LYC could prevent DEHP-induced lipid metabolism disorders via inhibiting the HIF-1α-mediated PPARα/PPARγ/FXR/LXR system. This study may provide a possible molecular mechanism for fatty liver induced by DEHP.

Cadmium sulfide (CdS) as one of the most common visible-light-responsive photocatalysts has been widely investigated for hydrogen generation. However, its low solar-hydrogen conversion efficiency caused by fast carrier recombination and poor catalytic activity hinders its practical applications. To address this issue, we develop a novel and highly efficient nickel-cobalt phosphide and phosphate cocatalyst-modified CdS (NiCoP/CdS/NiCoPi) photocatalyst for hydrogen evolution. The dual-cocatalysts were simultaneously deposited on CdS during one phosphating step by using sodium hypophosphate as the phosphorus source. After the loading of the dual-cocatalysts, the photocurrent of CdS significantly increased, while its electrical impedance and photoluminescence emission dramatically decreased, which indicates the enhancement of charge carrier separation. It was proposed that the NiCoP cocatalyst accepts electrons and promotes hydrogen evolution, while the NiCoPi cocatalyst donates electrons and accelerates the oxidation of sacrificial agents (e.g., lactic acid). Consequently, the visible-light-driven hydrogen evolution of this composite photocatalyst greatly improved. The dual-cocatalyst-modified CdS with a loading content of 5 mol % showed a high hydrogen evolution rate of 80.8 mmol.g(-1).h(-1), which was 202 times higher than that of bare CdS (0.4 mmol.g(-1).h(-1)). This is the highest enhancement factor for metal phosphide-modified CdS photocatalysts. It also exhibited remarkable stability in a continuous photocatalytic test with a total reaction time of 24 h.

In the plant male germline, transposable elements (TEs) are reactivated in the companion vegetative nucleus, resulting in siRNA production and the intercellular movement of these siRNAs to reinforce TE silencing in sperm. However, the mechanism by which siRNA movement is regulated remains unexplored. Here we show that ARID1, a transcription factor which is constitutively expressed in the vegetative nucleus but dynamically accumulates in the generative cell (the progenitor of sperm) to promote the second pollen mitosis, mediates siRNA movement to reinforce heterochromatic silencing in the male germline. We looked for regulators involved in the accumulation of ARID1 in the generative cell, and found that AGO9, a germline-specific AGO in Arabidopsis, is required for the accumulation of ARID1 in the generative cell. Mutations in either ARID1 or AGO9 lead to the interruption of not only the second pollen mitosis but also the movement of siRNA from the vegetative nucleus to the male germline, resulting in the release of heterochromatic silencing in the male germline. Moreover, conditional knockdown of ARID1 in the generative cell causes reduced heterochromatic silencing in both bicellular and mature pollen. This study provides insights into how a spatiotemporal transcription factor coordinates heterochromatic silencing and male germline maturation.

Visibility determination is a key requirement in a wide range of national and urban applications, such as national security, landscape management, and urban design. Mobile LiDAR point clouds can de...

Eleven cases of pleural mesothelioma and two cases of pleural normal tissue were detected using Fourier transform infrared spectroscopy. The differences between pleural mesothelioma and normal pleural tissues identified by comparison of their respective Fourier transform infrared spectra were as follows: (1) a higher relative intensity of the protein amide I band at 1641 cm–1 for pleural mesothelioma compared to normal pleural tissues, a pointed peak of amide II band at l550 cm–1 for pleural mesothelioma, and a higher relative intensity compared to normal pleural tissues, all relating to increased protein content in pleural mesothelioma; (2) a symmetric stretch of the vibration band of phosphodiester bonds in the nucleic acid molecules of pleural mesothelioma towards the long 1240 cm–1 wave, and a higher relative intensity compared to normal pleural tissues, indicating increased nucleic acid content of the pleural mesothelioma; (3) a lower relative intensity of the absorption peak near 2854–2922 cm–1 in the pleural mesothelioma compared to normal pleural tissue, indicating reduced lipid content of the pleural mesothelioma; (4) a lower relative intensity of the absorption peak near 1047 cm–1 associated with soluble sugar content of the pleural mesothelioma compared to normal pleural tissues. Our results show that Fourier transforms infrared spectra exists differences between pleural mesothelioma and normal pleural tissues. It is expected to become a new method for rapid identification of pleural mesothelioma.

Engineering highly porous SiC foams with interconnected cellular architecture and satisfactory compressive strength for the practical applications remains a challenging task. In the current work, SiC foams bonded by in-situ formed mullite phase were fabricated via polyurethane foaming using boehmite sol-coated SiC powder as the raw material. The strategy in the current work endowed the resultant products with ultrahigh porosity, interconnected pore structure, and a robust mullite bonding phase among the SiC particles. The resulting products with this cellular architecture possessed a high porosity level of 88.5% and maintained a robust compressive strength of 2.56 MPa. Our results showed that as-prepared products are promising for practical applications in the filtration, adsorption and catalytic areas.

Understanding the bimetallic interfacial effects on the catalytic CO2 reduction reaction (CO2RR) is an important and challenging issue. Herein, the geometric structure, electronic structure, and electrocatalytic property of Cu(submonolayer)/Au bimetallic interfaces are investigated by using density functional theory calculation. The results predict that the expansion of the Cu lattice can significantly modulate the CO2RR performance, the Cu(submonolayer)/Au interface has good surface activity promoting the reduction of CO2 to C2 compounds, and the final products of CO2RR on Cu/Au(111) and Cu/Au(100) surfaces are ethanol and a mixture of ethanol and ethylene, respectively. Furthermore, with regard to surface coverage and adsorption energy being two essential parameters for CO2RR, we demonstrate that the reaction of *CO and *CHO is the key process for obtaining the C2 products on the Cu/Au interface. This study offers a useful strategy for improving the surface activity and selectivity for CO2RR.

In this study, the root exudates of wetland plants, Pistia stratiotes, black algae, and Cyperus alternifolius, exposed to six phosphorus concentration gradients (0, 0.2, 1, 5, 10, and 20 mg/L) were characterized. The experimental seedlings were cultivated in Hoagland solutions, which were then extracted, decompressed, and concentrated with CH2Cl2; subsequently, a gas chromatography-mass spectrometry (GC-MS) analysis was performed to study the root exudates effects under different phosphorus concentrations. Results showed the existence of several organic compounds, such as alkanes, esters, alcohols, amines, benzene, and acids (phthalic acid, cycloheptasiloxane, benzoic acid, and cyclopentasiloxane) in the root exudates of the wetland plants. The relative contents of phthalate, benzene dicarboxylic acid, and cyclohexasiloxane in the root exudates first increased, and then decreased, with the change in phosphorus concentration. The relative contents of three compounds in Pistia were the highest at 1 mg/L of phosphorus, and the lowest relative contents of phthalic acid and benzene dicarboxylic acid were observed at 20 mg/L of phosphorus. However, the relative content of cyclohexasiloxane was the lowest in the absence of P stress. In black algae, the relative contents of the three compounds were 36.66, 16.24, and 14.61%, respectively. The relative content of cyclohexasiloxane in the black algae first decreased and then increased, with its lowest relative content occurring at 5 mg/L of phosphorus and the highest at 10 mg/L of phosphorus. In Cyperus alternifolius, the highest relative concentrations of the four compounds: phthalic acid, dimethyl phthalate, octadecane, and diphenyl sulfone in Cyperus were observed at 5 mg/L phosphorus and the lowest at 10 mg/L phosphorus.

The two-dimensional coupled map lattice (2D CML) is a spatiotemporal chaotic model with complex dynamic behavior and has high potential for designing stream cipher. We propose an offset 2D CML model by adding different offsets for each lattice. The offset 2D CML model has better chaotic properties, such as larger Lyapunov exponent (LE) and more uniform chaotic sequences, than the original 2D CML model, which provides a good basis for constructing stream cipher. We combine the offset 2D CML model with the partitioned cellular automata (PCA) and propose a stream cipher algorithm. In our algorithm, the PCA is used to control the extraction of pseudo-random number from the offset 2D CML model, which effectively hides the orbit information of system and enhances the difficulty of attacking chaotic sequences. Moreover, some fast nonlinear transform operations are specially introduced into our algorithm to further improve the complexity and the running speed. Theory analysis and simulation test both confirm that the proposed stream cipher algorithm has excellent statistical performance, high security and computational efficiency. It has great potential for guaranteeing data security in the Internet.

Effective restoration measures are required to protect earthen sites in historical heritage locations. In this study, sticky rice paste was added to in situ site soils and the water resistance and disintegration of the modified soils were investigated. Further, the influences of freeze–thaw, dry–wet, and Na2SO4-corrosion cycles on the compressive strength of the modified soil and its morphology were assessed. The results obtained indicate that the modified soil exhibited the highest water resistance and strength after 30 freeze–thaw and dry–wet cycles and 20 Na2SO4-corrosion cycles. This work is expected to provide future guidance on improved restoration and protection of earthen sites.

Since the introduction of antibiotics into clinical practices in the 1940s, antibiotics have become an integral part of animal production to meet the increasing human demand for animal-derived food...

2,3,5,6-Tetramethylpyrazine (TMP) has health care functions, especially for cardiovascular and cerebrovascular health. In this study, we found that Bacillus coagulans, a well-known probiotic, has t...

Engineering high performance cellular ceramics with both ultralow density and satisfactory compressive strength for practical applications still represents a grand challenge. Herein, alumina-based cellular ceramics bonded by in-situ formed mullite phase were constructed by Al2O3–Si-boehmite particle-stabilized foams. The gelation of boehmite sol improved the stability and harnessed the deformation of dried Al2O3–Si composite foam. The oxidation of silicon and further generation of in-situ mullite phase enhanced the chemical bond between alumina particles on cell walls, resulting in the superior mechanical properties. As an exemplar, the resulting cellular ceramic possessed the robust compressive strength of 2.26 MPa at a high porosity of 87.8%. The gelation-assisted Al2O3–Si particle-stabilized foams provide a facile and convenient strategy for construction of composite ceramic foams with high porosity and robust strength.

Aqueous rechargeable Zn-ion batteries (ZIBs) are safe, low cost, and environmentally friendly, yet the realization of both high capacity and long cycling life remains a major challenge. Herein, electrodeposited poly(1,5-naphthalenediamine) nanorods over nanoporous carbon are used as the cathode material to make aqueous ZIBs that can be operated within the voltage range of 0.1 – 1.8 ​V and have merits of both ionic battery and supercapacitor. Flexible carbon fiber fabric and thick carbon fiber felt are used as current collectors, respectively, to support the polymer/carbon composite with different mass loadings. With using the carbon fabric, flat pouch cells and cable-shaped micro cells are fabricated and show stable electrochemical performances when repeatedly bent at large angles. The pouch cells show maximum energy and power densities of 195 ​Wh kg‒1 and 104 ​W ​kg–1, respectively, and achieve a capacity retention of 91% after 10000 cycles. The prototype cell with using a 3 ​mm-thick carbon felt shows higher energy densities up to 7.7 ​mWh cm‒2 and better cycling stability, i.e., 100% capacity retention after 10000 cycles. Also, insights into the charge storage mechanism and superb cycling stability of our new polymer cathode are given.

Silver inorganic antibacterial agents have been widely used inbiotechnology, bioengineering science, electronics, optics and water treatment because of their strong bactericidal ability, high safety and durable antibacterial properties. In this paper, the preparation methods of silver nanoparticles are reviewed, including physical method, chemical method and biological method, in order to provide a reference for the further development and utilization of silver nano-antibacterial materials.

Selenium is an essential micronutrient that plays an important role in immunity. However, the mechanism that Selenium modulates mastitis is not fully clear. In this experiment, we investigated whether selenium can inhibit the activation of the NLRP3 inflammasome in a mouse model of Staphylococcus aureus-induced mastitis. Eighty BALB/c female mice were fed with experimental Selenium deficiency basal diet for 2 weeks to achieve the purpose of selenium consumption until pregnancy. Pregnant mice were randomly divided into four groups (control group; selenium supplement group; Staphylococcus aureus infection group and Staphylococcus aureus infection after selenium supplement group). Twenty-four hours after challenging, all mice were euthanized and mammary tissue samples were aseptically collected. Through pathological staining, western blot analysis, real-time fluorescence quantitative polymerase chain reaction analysis, and enzyme-linked immunosorbent assay, the regulation effect of Selenium on NLRP3 inflammasome was detected. The result showed that compared with the control group, selenium significantly inhibited the expression of NLRP3, ASC, Caspase-1, Caspase-1 p20, and Pro-IL-1β (p

In order to find a low temperature phase change material with a temperature range of 2–8°C, decyl alcohol (DA) and myristyl alcohol (MA) binary eutectic mixture was prepared based on theoretical ca...

In this article, an electrical doping method to realize the high n-type doping for a germanium (Ge) layer in a low-doped n-type Ge metal-oxide-semiconductor (MOS) structure in the accumulation condition is proposed, which maintains the initial crystal quality of Ge. The direct-bandgap electroluminescence (EL) from Ge light-emitting diode (LED) has been demonstrated with 1.5– $1.6~\mu \text{m}$ infrared emission using the metal/graphene/high- ${k}$ / interfacial layer (IL)/ ${n}$ -Ge MOS structure fabricated on bulk-Ge substrate. An onset current density of 5 A cm−2 is observed, which is, up to now, the lowest onset current density compared with the Ge LEDs fabricated on unstrained Ge substrates. These results indicate the superiority of the electrical doping method and the interface passivation technique on yielding the high-performance Ge-based LEDs and lasers.

Capillary electrophoresis (CE) is a high-efficiency method for aptamer selection, which exhibits many merits of high resolution, rapid separation, little sample consumption, and no immobilization. However, the influence of injection input on CE systematic evolution of ligands via exponential enrichment (SELEX) is controversial because the low injection volume may result in an insufficient capacity of the oligonucleotides library. In this research, neuron-specific enolase (NSE) was used as a model protein to investigate the effects of library input capacity on aptamer selection for clarifying the validity of CE-SELEX. Four different concentrations of initial libraries (0.1, 1, 10 and 100 μmol/L) were utilized into aptamer selection. The affinity of the initial library and sub-libraries after three rounds of selection were evaluated. The results showed that there was no significant difference in the affinity of four different sub-libraries, and aptamers with micromolar dissociation constant (KD) were all obtained after two rounds of selection. In addition, the sequences obtained via high concentration ssDNA library screening were more diverse, but the affinity of them was not enhanced. The NSE aptamer Seq qN-01 obtained by two rounds of selection had a KD of (4.72 ± 0.15) μmol/L, and also presented a good specificity. In conclusion, library input capacity could increase the sequence diversity but had no considerable effects on the efficiency of aptamer selection.

Calreticulin (CRT) is closely related to cancer, and it is considered to be a novel biomarker for invasion and metastasis of breast cancer, as well as an indicator of staging and prognosis. Here, we screened and identified aptamers of CRT for the first time with capillary electrophoresis-systematic evolution of ligands by exponential enrichment (CE-SELEX) technology. The Apt 23 with high affinity and specificity was screened and verified by CE, isothermal titration calorimetry and gold nanoparticles-based colorimetric assay. By using FAM-labeled Apt 23 (FAM-Apt23) as an affinity probe, CRT was detected in the concentration range of 1–1000 nmol/L in serum by laser-induced fluorescence detector with a detection limit of 0.5 nmol/L. FAM-Apt 23 could also be used as an immunofluorescence imaging probe, which could be bound to the surface of breast cancer cells 4T1 with overexpressed CRT. Preliminary studies showed that Apt 23 could be used as aptamer probe for CRT recognition and detection.

Aptamer is oligonucleotide with high affinity and specificity toward the target which is obtained via systematic evolution of ligands by exponential enrichment (SELEX). However, due to the complexity of environmental factors and the unknown influence on the selection and application of aptamers, the optimization of multiple environmental factors through conventional experiments requires a huge amount of work and samples, so there are few systematic studies. Capillary electrophoresis (CE)-SELEX has become a highly efficient technique for aptamers screening because of the advantages of CE, e.g. microscale, high efficiency and low cost. In this work, human apo-transferrin (A-TF) was used as a model to study the effects of factors based on CE, including length of ssDNA library, incubation temperature, type and pH value of incubation buffer, metal ions etc. The results showed that shorter ssDNA library had higher affinity with the target protein. Incubation temperature, type and pH value of incubation buffer affected the formation of complex. Low concentrations of K+, Ca2+ and Mg2+ metal ions promoted the formation of complexes. The A-TF aptamer Seq A3 obtained by three rounds of selection had a dissociation constant (KD) of 0.476 μmol/L, and its affinity and specificity were verified via CE-laser induced fluorescence in human serum. The results indicated that Seq A3 could specifically recognize A-TF in serum.

The microstructure of large-capacity anodes is of great importance in determining the performance of sodium- and potassium-ion batteries. Yolk-shell nanostructures promise excellent structural stability but suffer from insufficient charge transfer rate during cycles. Herein, we tackle this challenge by constructing a single-walled carbon nanotube (SWNT) internally bridged yolk-shell structure, inside which SWNTs cover the surface of the yolk and connect the yolk and shell, for better electron/ion transportation. Combining the merits of both yolk-shell structure and conductive SWNT channels, the as-prepared Fe

Climate change poses a serious threat to biodiversity. Predicting the effects of climate change on the distribution of a species' habitat can help humans address the potential threats which may change the scope and distribution of species. Pterocarya stenoptera is a common fast‐growing tree species often used in the ecological restoration of riverbanks and alpine forests in central and eastern China. Until now, the characteristics of the distribution of this species' habitat are poorly known as are the environmental factors that influence its preferred habitat. In the present study, the Maximum Entropy Modeling (Maxent) algorithm and the Genetic Algorithm for Ruleset Production (GARP) were used to establish the models for the potential distribution of this species by selecting 236 sites with known occurrences and 14 environmental variables. The results indicate that both models have good predictive power. Minimum temperature of coldest month (Bio6), mean temperature of warmest quarter (Bio10), annual precipitation (Bio12), and precipitation of driest month (Bio14) were important environmental variables influencing the prediction of the Maxent model. According to the models, the temperate and subtropical regions of eastern China had high environmental suitability for this species, where the species had been recorded. Under each climate change scenario, climatic suitability of the existing range of this species increased, and its climatic niche expanded geographically to the north and higher elevation. GARP predicted a more conservative expansion. The projected spatial and temporal patterns of P. stenoptera can provide reference for the development of forest management and protection strategies., Minimum temperature of coldest month (Bio6), mean temperature of warmest quarter (Bio10), annual precipitation (Bio12), and precipitation of driest month (Bio14) were important environmental variables influencing the prediction of the Maxent model. Under each climate change scenario, climatic suitability of the existing range of this species increased, and its climatic niche expanded geographically toward farther north and higher elevation. The GARP predicted a more conservative expansion.