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Quasi‐solid polymer electrolyte (QPE) lithium (Li)‐metal battery holds significant promise in the application of high‐energy‐density batteries, yet it suffers from low ionic conductivity and poor oxidation stability. Herein, a novel self‐built electric field (SBEF) strategy is proposed to enhance Li+ transportation and accelerate the degradation dynamics of carbon‐fluorine bond cleavage in LiTFSI by optimizing the termination of MXene. Among them, the SBEF induced by dielectric Nb4C3F2 MXene effectively constructs highly conductive LiF‐enriched SEI and CEI stable interfaces, moreover, enhances the electrochemical performance of the QPE. The related Li‐ion transfer mechanism and dual‐reinforced stable interface are thoroughly investigated using ab initio molecular dynamics, COMSOL, XPS depth profiling, and ToF‐SIMS. This comprehensive approach results in a high conductivity of 1.34 mS cm−1, leading to a small polarization of approximately 25 mV for Li//Li symmetric cell after 6000 h. Furthermore, it enables a prolonged cycle life at a high voltage of up to 4.6 V. Overall, this work not only broadens the application of MXene for QPE but also inspires the great potential of the self‐built electric field in QPE‐based high‐voltage batteries. [ABSTRACT FROM AUTHOR]

Quasi‐solid polymer electrolyte (QPE) lithium (Li)‐metal battery holds significant promise in the application of high‐energy‐density batteries, yet it suffers from low ionic conductivity and poor oxidation stability. Herein, a novel self‐built electric field (SBEF) strategy is proposed to enhance Li+ transportation and accelerate the degradation dynamics of carbon‐fluorine bond cleavage in LiTFSI by optimizing the termination of MXene. Among them, the SBEF induced by dielectric Nb4C3F2 MXene effectively constructs highly conductive LiF‐enriched SEI and CEI stable interfaces, moreover, enhances the electrochemical performance of the QPE. The related Li‐ion transfer mechanism and dual‐reinforced stable interface are thoroughly investigated using ab initio molecular dynamics, COMSOL, XPS depth profiling, and ToF‐SIMS. This comprehensive approach results in a high conductivity of 1.34 mS cm−1, leading to a small polarization of approximately 25 mV for Li//Li symmetric cell after 6000 h. Furthermore, it enables a prolonged cycle life at a high voltage of up to 4.6 V. Overall, this work not only broadens the application of MXene for QPE but also inspires the great potential of the self‐built electric field in QPE‐based high‐voltage batteries. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to establish a benchmark glycan profile for commercial therapeutic monoclonal antibodies (mAbs) approved by the US Food and Drug Administration (FDA). Methods: We conducted a rigorous comparison of glycosylation data from the regulatory submissions for FDA-approved therapeutic antibodies up to May 2023. This analysis includes over 150 mAbs produced by various mammalian cell expression systems. Results: The study identified nine prevalent glycan epitopes across all FDA-approved monoclonal antibodies produced by different expression systems. These epitopes include terminal N-acetylglucosamine, core fucose, terminal galactose, high mannose, α-galactose, terminal α2,3-linked N-acetylneuraminic acid, terminal α2,6-linked N-glycolylneuraminic acid, triantennary structure, and bisecting N-acetylglucosamine, thus establishing a benchmark glycan profile. Conclusions: The findings of this study have significant implications for therapeutic antibody development, quality control, and regulatory compliance. The benchmark glycan profile enables the assessment of glycosylation consistency and comparability across a diverse range of antibody products, ensuring improved product quality within the biopharmaceutical industry. [ABSTRACT FROM AUTHOR]

Background: Intractable postpartum hemorrhage (PPH) during cesarean section has been a significant concern for obstetricians. We aimed to explore the effectiveness and safety of a new type of uterine compression suture, the step-wise surgical technique of knapsack-like sutures for treating intractable PPH caused by uterine atony and placenta factors in cesarean section. Methods: The step-wise surgical technique of knapsack-like sutures was established on the basis of the artful combination of vertical strap-like sutures and an annular suture-ligation technique. This novel surgical technique was applied to 34 patients diagnosed with PPH during cesarean section due to severe uterine atony and placental factors in our department. The hemostatic effects, clinical outcomes and follow-up visit results were all reviewed and analyzed. Results: This new uterine compression suture successfully stopped bleeding in 33 patients, and the effective rate was 97.06%. Only 1 patient failed and was changed to use bilateral uterine arterial embolization and internal iliac artery embolization. The follow-up visits indicated that 33 patients restored menstruation except for 1 who was diagnosed with amenorrhea. The gynecological ultrasound tests of all the patients suggested good uterine involutions, and they had no obvious complaints such as hypogastralgia. Conclusions: This step-wise surgical technique of knapsack-like uterine compression sutures can compress the uterus completely. It is a technique that can conserve the uterus and fertility function without special equipment in caesarean section for PPH, with the characteristics of being safe, simple and stable (3 S) with rapid surgery, reliable hemostasis and resident doctor to operation (3R). [ABSTRACT FROM AUTHOR]

The fractional uncertainty of the 40Ca+ optical clock in our laboratory has been evaluated to be 2.2 × 10 − 17 , but it is difficult to evaluate the statistical uncertainty of the output frequency at this level, limited by the frequency stability associated with the quantum projection noise (QPN). A reduction in the stability is required to shorten the averaging time for a certain statistical uncertainty level. To improve the stability, the Ramsey method is introduced in the locking process. To improve the reliability and continuity, we introduce the idea of using auxiliary Rabi probes to avoid fringe slips in the Ramsey interrogation and to automatically search for resonance. The stability of a single 40Ca+ ion frequency standard is improved from 6.3 × 10 − 15 / τ to 2.5 × 10 − 15 / τ , where τ is the averaging time in seconds, which is close to the QPN limit for an 80-ms-long Ramsey interrogation. We obtain a stability of 1.5 × 10 − 17 at an averaging time of 21 000 s and an uptime rate of 93.8% for a 34-h-long run. These methods can easily be applied to other ion or neutral atom optical clocks. [ABSTRACT FROM AUTHOR]

In this contribution, we investigate the influence of thermal processing routes on the formability of medium Mn steel by assessing the strain hardening coefficient and anisotropy factor using the uniaxial tensile test. Medium Mn steel processed by intercritical annealing (IA) at 680 °C for 4 h demonstrates better formability than steel treated with a combination of IA at 800 °C for 10 min and quenching and partitioning (Q&P), based on the much higher strain hardening coefficient (n) and comparable anisotropy factor (r, rm, ∆r). The higher strain hardening coefficient of medium Mn steel with single IA treatment is ascribed to the enhanced transformation-induced plasticity (TRIP) effect resulting from the large amount of austenite that is transformed into martensite during deformation. In addition, the IA process allows for the production of medium Mn steel with high ductility, which is beneficial for its high formability and good 'part ductility' in lightweight automotive applications. [ABSTRACT FROM AUTHOR]

Efficient, stable, and inexpensive electrocatalysts are essential to overcome the high overpotential and slow kinetics of the oxygen evolution reaction (OER) process during water electrolysis applications. 2D transition metal carbides (MXene) show great potential in functional heterogeneous interface engineering for electrocatalytic OER. However, it is still a challenge to regulate the interlayer space and realize the heterogeneous layer‐by‐layer ordered embedding for MXene. Herein, a simple hydrothermal‐assisted strategy is proposed to prepare highly conductive Ti3C2Tx MXene supported by synergized Ni2+, Co2+, and Fe3+ with bilayer H2O, which significantly enlarges the interlayer distances and improves the interlayer ion concentrations. Benefiting from modulated interface chemistry, embedded metal ions undergo multi‐directional in situ growth on the MXene substrate, thereby forming a stable 0D/2D@2D nano‐hybrid material (NiFe/MX‐HT). Combining density functional theory calculations with experiments demonstrates that MXene offers a framework for electron transfer, enhances the exposure of active sites, modulates the electronic structure, and greatly reduces the energy barrier of the rate‐determining step in the process of OER. Thus, NiFe/MX‐HT requires only 230 mV to achieve 10 mA cm−2 and maintains stability even after operating at 100 mA cm−2 for 150 h. This work offers new insights into exploring various functional MXene‐based heterogeneous materials. [ABSTRACT FROM AUTHOR]

The aim of this study is the fabrication of unprecedented neuroelectrodes, replete with exceptional biological and electrical attributes. Commencing with the synthesis of polyethylene glycol and polyethyleneimine-modified iron oxide nanoparticles, the grafting of Dimyristoyl phosphatidylcholine was embarked upon to generate DMPC-SPION nanoparticles. Subsequently, the deposition of DMPC-SPIONs onto a nickel–chromium alloy electrode facilitated the inception of an innovative neuroelectrode–DMPC-SPION. A meticulous characterization of DMPC-SPIONs ensued, encompassing zeta potential, infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction analyses. Evaluations pertaining to hemolysis and cytotoxicity were conducted to ascertain the biocompatibility and biosafety of DMPC-SPIONs. Ultimately, a comprehensive assessment of the biocompatibility, electrochemical properties, and electrophysiological signal acquisition capabilities of DMPC-SPION neuroelectrodes was undertaken. These findings conclusively affirm the exemplary biocompatibility, electrochemical capabilities, and outstanding capability in recording electrical signals of DMPC-SPION neuroelectrodes, with an astounding 91.4% augmentation in electrode charge and a noteworthy 13% decline in impedance, with peak potentials reaching as high as 171 μV and an impressive signal-to-noise ratio of 15.92. Intriguingly, the novel DMPC-SPION neuroelectrodes herald an innovative pathway towards injury repair as well as the diagnosis and treatment of neurological disorders. [ABSTRACT FROM AUTHOR]

There are unrevealed factors that bring about the performance variations of resistive switching devices. In this work, Pt/CeOx/Pt devices prepared by magnetron sputtering showed rectification in their asymmetrical current–voltage (I–V) curves during voltage sweeps. X-ray photoelectron spectroscopy showed that the deposited CeOx film had an inhomogeneous composition, and more oxygen vacancies existed in CeOx near the top electrode. The asymmetrical resistance change of the Pt/CeOx/Pt devices can be explained by the presence of more charged oxygen vacancies in CeOx near the top electrode, along with the Schottky conduction mechanism. This work reveals that the compositional inhomogeneity is inevitable in the magnetron sputtering of oxide targets like CeO2 and can be an important source of device-to-device and cycle-to-cycle variations of memristors. [ABSTRACT FROM AUTHOR]

Progress of the 40Ca+ ion optical clock based on the 42S1/2 – 3d 2D5/2 electric quadrupole transition is reported. By setting the drive frequency to the "magic" frequency Ω0, the frequency uncertainty caused by the scalar Stark shift and second-order Doppler shift induced by micromotion is reduced to the 10−19 level. By precisely measuring the differential static scalar polarizability Δα0, the uncertainty due to the blackbody radiation (BBR) shift (coefficient) is reduced to the 10−19 level. With the help of a second-order integrating servo algorithm, the uncertainty due to the servo error is reduced to the 10−18 level. The total fractional uncertainty of the 40Ca+ ion optical clock is then improved to 2.2× 10−17, whereas this value is mainly restricted by the uncertainty of the BBR shift due to temperature fluctuations. The state preparation is introduced together with improvements in the pulse sequence, and furthermore, a better signal to noise ratio (SNR) and less dead time are achieved. The clock stability of a single clock is improved to. [ABSTRACT FROM AUTHOR]

In order to improve the contour error accuracy of two-dimensional linear motor, an improved cross-coupled control (CCC) scheme combining real-time contour error estimation and model-free adaptive control (MFAC) is proposed. The real-time contour error estimation method is based on CCC theory and coordinate transformation idea. It can accurately determine the contour error point of regular contour and avoid the influence of tracking error on the contour error. At the same time, for the design of two-axis error controller, only the input and output data generated by two-dimensional linear motor in reciprocating motion are used to design a multiple input multiple output-model-free adaptive control (MIMO-MFAC) algorithm, this algorithm avoids the dependence on accurate mathematical model and reduces the control difficulty. The experimental comparison showed that the proposed method improves the system tracking accuracy and contour accuracy, and verifies the proposed method correctness and effectiveness. [ABSTRACT FROM AUTHOR]

Superparamagnetic iron oxide nanoparticles (SPIONs) conjugated with hyaluronic acid (HA) functional groups have potential applications as cell targeting materials. However, SPIONs incubated with high-molecular weight HA can result in severe agglomeration. In this work, we found that when modified with degraded HA (hyaluronan oligosaccharides (oHAs)), the nanoparticles were uniformly dispersed with small hydrodynamic sizes, and the oHA-modified SPIONs exerted minimal cytotoxicity. With the same functional groups as HA, the oHA-modified SPIONs may have various biomedical applications. [ABSTRACT FROM AUTHOR]

The Bayinsukhtu tungsten deposit is a newly discovered quartz‐vein tungsten deposit in the Xing'an–Mongolia Orogenic Belt (XMOB) in southern Mongolia, hosted by the Bayinsukhtu granite porphyry. The granite porphyry is located mainly south of the study area, over 3 km2. The rock consists of quartz and feldspar phenocrysts in a fine‐grained matrix, also mainly composed of feldspar and quartz. The granite porphyry samples demonstrate high SiO2 and high alkalinity. All samples also straddle the high‐potassium calc‐alkaline series. In a plot of the molar ratios of A/NK versus A/CNK, the granites are metaluminous. The chondrite‐normalized REE patterns are characterized by large negative Eu anomalies and fractionated LREEs. The U–Pb age of zircons from the granite porphyry is 298.8 ± 1.8 Ma, and the Sm–Nd age of the five wolframite samples from the tungsten deposit is 303 ± 19 Ma. The cooling age of the granite porphyry and tungsten mineralization is within the error of measurement and is of the Late Carboniferous age. Geological and geochronological evidence shows that the tungsten mineralization and the granite porphyry at Bayinsukhtu are genetically closely related and that they are results of Carboniferous magmatism. Their tectonic setting is related to the accretion of the Central Asian Orogenic Belt during the late Paleozoic era. The results show that the ages of the quartz porphyry and tungsten mineralization are the same within the margin of error. Furthermore, the geological and geochronological evidence indicates that the quartz porphyry and tungsten mineralization are products of Carboniferous magmatism. Their tectonic settings are related to the accretion of the Central Asian Orogenic Belt (CAOB) during the late Paleozoic era. [ABSTRACT FROM AUTHOR]

The subcellular distributions of nanoparticles in the brain are important for their biological application. We synthesized and characterized the superparamagnetic iron oxide nanoparticles (SPIONs) modified with poly (ethylene glycol) (PEG) and polyethylenimine (PEI) (PEG/PEI-SPIONs), and with dimyristoylphosphatidylcholine (DMPC) (DMPC-SPIONs). The nanoparticles were unilaterally injected into the left substantia nigra of rat brains. The distributions of the nanoparticles in the left brains of the rats were examined by ICP-OES (inductively coupled plasma optical emission spectrometer) and TEM (transmission electron microscopy) at 24 h after the injection. Iron was found in the olfactory bulb, temporal lobe, frontal cortex, thalamus and brain stem at 24 h after the injection of DMPC-SPIONs and PEG/PEI-SPIONs. In the rat substantia nigra, most DMPC-SPIONs were distributed in and on the myelin sheath around axons or on cell membranes, some were in cells. As a comparison, less iron was found in the rat brains at 24 h after the injection of PEG/PEI-SPIONs. Our experiments suggest DMPC modification on SPIONs be a safe and effective method for increasing SPIONs distribution on the cell membranes. This work is encouraging for further study on using DMPC-SPIONs for efficient drug delivery or for deep brain stimulation of neurons in a magnetic field. [ABSTRACT FROM AUTHOR]

An innovative self-healing polydimethylsiloxane (PDMS) elastomer, namely, PDMS-TFB, is reported by incorporating the reversibly dynamic imine bond as the self-healing points into the PDMS networks. The PDMS-TFB elastomer features good optical transmittance (80%) in full visible light region, high stretchability (≈700%), and excellent autonomous self-healing ability at room temperature. Surprisingly, the self-healing behavior can take place in water and even at a temperature as low as −20 °C in air, showing a promising outlook for broader applications. As a proof-of-concept, this study demonstrates the use of the PDMS-TFB elastomer for preparing anticorrosion coating and adhesive layer, and also the use of such an elastomer to be the platform for fabricating the flexible interconnector and chemical sensor. Remarkably, no significant difference is observed between the pristine and healed samples. Taking full advantage of these unique properties, it is anticipated that such a PDMS-TFB elastomer shows wide applications in the fields of materials science, electronics, biology, optics, etc. [ABSTRACT FROM AUTHOR]

Liujiaping VMS (volcanic massive sulfide) deposit contains mainly copper and zinc, which is located at the Longmenshan orogenic belt of the northwestern margin of Yangtze block. The deposit is hosted in Neoproterozoic Datan terrane (composed of Datan granitoids and Liujiaping group) and is a typical, and the biggest, VMS deposit in this area. The Datan granitoids and Liujiaping group are contemporary and both parental magmas have the same genesis. The tectonic evolution history of Northwestern Yangtze is complicated. Chronology, isotope and geochemistry of the Liujiaping VMS ores and wall rocks (especially the Datan granitoids) are analyzed to restrict the tectonic progress. High-precision secondary ion mass spectrometry (SIMS) analysis of the Datan granitoids resulted in two concordant ages, 815.5 ± 3.2 Ma and 835.5 ± 2.6 Ma, which are contemporary with the Liujiaping Cu-Zn ore and volcanics. The wall rocks are characterized by enrichment in LREE and with a weak negative anomaly of Eu. The Pb isotope data of sulfide and volcanics from the Liujiaping deposit indicate that the material source is lower crust. Together with variable negative anomalies of high strength field elements HFSE (Th, Nb, Ta, Zr, Hf, P and Ti), positive εNd (825 Ma) values (+1.8 to +3.1) and the Nd model age T2DM = 1.2-1.3 Ga, it shows that the Liujiaping deposit and wall rocks were formed by partial melting of Mesoproterozoic lower crust. Geological and geochemical characteristics of Liujiaping deposit indicate that this deposit was formed during subduction of the oceanic crust. This study clarified that that the Liujiaping deposit and the northwestern margin of the Yangtze block were part of an arc setting at ~820 Ma rather than intra-continental rift. [ABSTRACT FROM AUTHOR]

In this work, a novel set of methods is prοposed for tuning the oxygen vacancy distribution through the combination of several effects. More specifically, the incorporation of a Ti nano-island (NI), as well as the insertion of a thin layer of HfO 2 with 10 nm thickness and the subsequent enforcement of an annealing step at 400 ℃ are employed to improve the performance of the resistive switching memory devices. The acquired results indicate that the embedded Ti NI array can significantly reduce the switching voltage and the statistical dispersion of the switching characteristics, whereas the increase of both the high resistance state (HRS) and low resistance state (LRS) resistance levels and the reduction of the operating current values are attributed to the existence of the HfO 2 layer. Subsequently, the annealing process under air conditions can effectively reduce the oxygen vacancy content within the device and further improve the R HRS and on/off ratio. The reduction of the oxygen vacancy concentration is caused by the diffusion of oxygen ions in the air to the dielectric layer during annealing. Hence, it is concluded that the simultaneous incorporation of a Ti NI, a functional layer and a rapid thermal annealing step are regarded as a novel promising and practical technology for significantly improving the whole performance of the memristive elements. [Display omitted] • Ti NI can significantly improve the whole performance of the memristive elements. • A rapid thermal annealing can improve the performance of the memristive elements. • The annealing can effectively reduce the oxygen vacancy concentration within the device. [ABSTRACT FROM AUTHOR]

Water-soluble superparamagnetic iron oxide nanoparticles (SPIONs) were synthesized by the thermal decomposition of iron (III) acetylacetonate (Fe(acac) 3 ) in the mixture of poly(ethylene glycol) (PEG) and poly(ethylene imine) (PEI). The average sizes of the SPIONs are in the range of 6–12 nm, which could be tuned by adjusting the synthesis temperature and molecular weight of PEI. Benefiting from the coating of hydrophilic PEG and PEI, the resulted SPIONs showed excellent colloidal stability in deionized water and other physiological buffers. The XRD patterns indicate that the obtained SPIONs are magnetite. The PEG/PEI-SPIONs exhibited high r 2 / r 1 ratio. In vivo magnetic resonance imaging (MRI) of the mouse brains after intravenous injection of the SPIONs showed their good contrast effect. Considering the facile fabrication process and excellent imaging performance of the water soluble PEG-SPIONs and PEG/PEI-SPIONs, it is believed that the SPIONs will find great potential in advanced MRI. [ABSTRACT FROM AUTHOR]

PEG and PEG/PEI modified superparamagnetic iron oxide nanoparticles (SPIONs) were synthesized by the thermal decomposition of iron (III) acetylacetonate (Fe(acac) 3 ) in poly (ethylene glycol) (PEG) containing poly (ethylene imine) (PEI) (0 or 0.3 g). PEG/PEI-SPIONs were coated with Tween 80 (PEG/PEI/Tween 80-SPIONs). Fourier transform infrared spectroscopy (FTIR) analyses indicated that PEG, PEG/PEI and PEG/PEI/Tween 80 were attached to the surfaces of the SPIONs. The PEG-SPIONs, PEG/PEI-SPIONs and PEG/PEI/Tween 80-SPIONs performed excellent colloidal stability in the phosphate buffered saline (PBS), and in deionized water with the mean hydrodynamic sizes of 19.5, 21.0, 24.0 nm and the zeta potentials of -5.0, 35.0, 19.0 mV, respectively. All the SPIONs showed low cytotoxicity assessed by the MTT assay. In vivo magnetic resonance imaging (MRI) of the Kunming (KM) mouse brains were performed, the PEG-SPIONs, PEG/PEI-SPIONs and PEG/PEI/Tween 80-SPIONs exhibited vascular imaging effects in bulbus olfactorius, frontal cortex, temporal, thalamus and brain stem of the mouse brains after 24 h intravenous injection of the nanoparticles. The SPIONs have potentials as MRI contrast agents in the mouse brains. [ABSTRACT FROM AUTHOR]

Polylysine (PLL) coated iron oxide nanoparticles (SPIONs) have potential in biomedical application. In the present work PEG coated SPIONs (PEG-SPIONs) with the particle size of 9.4±1.4 nm were synthesized by thermal decomposition of Fe(acac) 3 in PEG, and then coated with PLL (PLL/PEG-SPIONs). The PEG-SPIONs and PLL/PEG-SPIONs were superparamagnetic with the saturation magnetization of 53 and 44 emu/g, respectively. The hydrodynamic diameter of PEG-SPIONs in deionized water was 18.8 nm, which increased to 21.3−28.2 nm after mixing with different amount of PLL. The zeta potentials of PLL/PEG-SPIONs were −8.9 − −3.4 mV which were changing with time. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses indicated that PLL was attached to the PEG-SPIONs. [ABSTRACT FROM AUTHOR]

Background: The success of stem cell therapy for knee osteoarthritis (KOA) in preclinical animal models has accelerated the pace of clinical translation. However, it remains uncertain whether the current scientific evidence supports the clinical application of stem cells in treating KOA. A comprehensive evaluation of the safety and efficacy of stem cell therapies and scientific evidence quality is necessary. Methods: Using "stem cells" and "knee osteoarthritis" as the search terms, several databases, including PubMed, Web of Science, Cochrane, Embase, and Clinicaltrials.gov, were searched on August 25, 2022, and updated on February 27, 2023. Clinical studies that reported adverse reactions (ARs) of stem cell therapy in KOA patients were included without limiting the type of studies. Quantitative systematic reviews of stem cell therapy for KOA that conducted meta-analysis were included. Two researchers conducted literature screening and data extraction independently, and the evidence quality was evaluated according to the Institute of Health Economics and AMSTAR 2 criteria. Results: Fifty clinical studies and 13 systematic reviews/meta-analyses (SRs/MAs) were included. Nineteen ARs were reported in 50 studies, including five knee-related ARs, seven common ARs, and seven other ARs. Some studies reported over 10% prevalence of knee pain (24.5%; 95% CI [14.7%, 35.7%]), knee effusion (12.5%; 95% CI [4.8%, 22.5%]), and knee swelling (11.9%; 95% CI [3.5%, 23.5%]). Additionally, two studies have reported cases of prostate cancer and breast tumors, respectively. However, these two studies suggest that stem cell therapy does not bring significant ARs to patients. SRs/MAs results revealed that stem cell therapy relieved pain in patients over time but did not improve knee function. However, current clinical studies have limited evidence regarding study objectives, test designs, and patient populations. Similarly, SRs/MAs have inadequate evidence regarding study design, risk of bias assessment, outcome description, comprehensive discussion, and potential conflicts of interest. Conclusions: The inefficacy of stem cells, the risk of potential complications, and the limited quality of evidence from current studies precluded any recommendation for using stem cell products in patients with KOA. Clinical translation of stem cell therapies remains baseless and should be cautiously approached until more robust evidence is available. PROSPERO registration number: CRD42022355875. [ABSTRACT FROM AUTHOR]

Highlights: [•] The SPIONs are jointly coated by PEG and PVP. [•] The size of SPIONs can be controlled via changing the reaction temperature and reaction time. [•] The SPIONs performed very good colloidal stability in physiological buffers. [•] The DOX-loaded SPIONs had very high encapsulation efficiency (more than 90%). [•] The DOX-loaded SPIONs showed pH-responsive drug release. [ABSTRACT FROM AUTHOR]

Systematic investigation has been made on the structure and dielectric properties of Mn CO3-doped barium titanate-based X8R ceramics, to reveal the relationship between the manufacturing process and dielectric properties. The dielectric ceramic sintered at 950°C showed high permittivity and low dielectric loss, meeting X8R specifications. Transmission electron microscopy and EDS analysis were used. The results suggested that the temperature-stable BaTiO3-based X8R ceramics with the good dielectric properties can be prepared through the BaTiO3 calcined at 1150°C and doped with 0.7 wt% Mn CO3. [ABSTRACT FROM AUTHOR]

Abstract: Superparamagnetic iron oxide nanoparticles were synthesized by thermal decomposition of iron (III) acetylacetonate (Fe(acac)3) in PEG containing poly(vinyl pyrrolidone) (PVP) or poly(ethylene imine) (PEI). The morphologies and phase compositions of the nanoparticles were determined by transmission electron microscopy and X-ray diffraction, respectively. The surface coating of the nanoparticles was recognized using Fourier transform infrared spectroscopy and the presence of the surface coating was confirmed by Thermogravimetric analyses. Magnetic properties were measured using superconducting quantum interference device. The zeta potentials and hydrodynamic sizes of the nanoparticles were determined using nano-particle and zeta potential analyzer. The superparamagnetic iron oxide nanoparticles with sizes from 4.1nm to 14.9nm were prepared in the present work, which could be tuned by varying factors such as the reaction temperature, the reaction time, and the PVP or PEI contents. The superparamagnetic nanoparticles were jointly coated with PEG/PVP or PEG/PEI. With hydrodynamic sizes smaller than 40nm and neutral or positive zeta potentials these superparamagnetic iron oxide nanoparticles exhibited higher dispersion stability in deionized water and in phosphate buffered saline as compared with the superparamagnetic iron oxide nanoparticles coated with PEG alone. This work demonstrates that superparamagnetic iron oxide nanoparticles with modulated properties can be prepared simply by using the improved polyol method. [Copyright &y& Elsevier]

To explore the optimal transplantation strategy of bone marrow mesenchymal stem cells in subacute traumatic spinal cord injury in animal experiments in order to provide reference for future animal studies and clinical research. The PubMed, Embase and Web of Science databases were systematically searched (inception to January 4, 2022). Literature search, data extraction and bias assessment were performed by two independent reviewers. A total of 50 articles were included for analysis. Results of both traditional meta-analysis and network meta-analysis showed that high-dose (≥1 × 106) transplantation was significantly better than low-dose (<1 × 106) transplantation and intralesional transplantation was significantly better than intravenous transplantation. Given the limited quality of evidence from current animal studies, more high-quality head-to-head comparisons are needed in the future to delve into the optimal transplantation strategy for stem cells. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The Sr1.56Ba0.4SiO4:0.04Eu2+ phosphors were prepared via a combustion reaction and following the calcination method at low temperature. The influences of the amount of the uncommonly used SrCl2 flux, different calcination temperatures and time on the structure and the photoluminescence (PL) properties of the phosphors were investigated. Under the excitation of 450nm blue light, the phosphor shows the intense broad emission band from 490nm to 650nm, and the emission peak is centered at 553nm. The luminescence intensity of Sr1.56Ba0.4SiO4:0.04Eu2+ was very sensitive to the crystallinity and morphology characteristics of the phosphor. The phosphor calcined at 950°C for 3h in 20%H2/80%Ar atmosphere exhibits improved PL properties due to its high crystallinity and excellent morphology characteristics. The use of the SrCl2 flux provides a novel way to improve the crystallinity of the silicates phosphors at low preparation temperature. [Copyright &y& Elsevier]

Abstract: Temperature-dependent material parameters and device performances of Ga x In1− x As1− y Sb y TPV cells applied in low temperature (800–1200°C) radiators are simulated using the PC-1D. As is well known, the optimum bandgap (Eg ) decreases towards lower radiator temperatures. So far, the lowest achievable Eg of Ga x In1− x As1− y Sb y at 300K is 0.5eV. We mainly considering the Ga0.8In0.2As0.18Sb0.82 (Eg =0.5eV) TPV cell. The effects of doping concentration and recombination mechanisms of the emitter layer on photovoltaic conversion efficiencies (ηcel ) are analyzed in detail, and ηcel can be improved by optimizing doping concentration and suppressing carrier recombination. The effects of GaSb window layer on ηcel are also presented. It shows the type-II energy-band alignment GaSb(window)/GaInAsSb(emitter) heterostructure affect ηcel mainly through Voc . For the first time, the effects of operating temperatures on device performances are analyzed based on temperature-dependent material parameters, and the temperature coefficients of the device performances are presented. [Copyright &y& Elsevier]

Abstract: Heterojunction light-emitting diodes with ZnO/Si structure were fabricated on both high-resistivity (p) and low-resistivity (p+) Si substrates by metal–organic chemical vapor deposition technology. Fairly good rectifications were observed from the current–voltage curves of both heterojunctions. Ultraviolet (UV) and blue-white electroluminescence (EL) from ZnO layer were observed only from ZnO/p+-Si heterojunction under forward bias at room temperature (RT), while strong infrared (IR) EL emissions from Si substrates were detected from both ZnO/p-Si and ZnO/p+-Si heterojunctions. The UV and IR EL mechanisms have been explained by energy band structures. The realization of RT EL in UV–visible and IR region on Si substrate has great applicable potential for Si-based optoelectronic integrated circuits. [Copyright &y& Elsevier]

Abstract: More than 400 Moderate Resolution Imaging Spectroradiometer (MODIS) images of dust storm events were collected and analyzed, and individual events were tracked back to their origins. Dust tracks were determined from color composite images, brightness temperature difference (BTD) and the NOAA Hybrid Single-Particle Lagrangian Integrated Trajectory model. The results showed that five regions (sandy lands in central Inner Mongolia and the adjacent area of Mongolia; the Gobi Desert in Xinjiang and Gansu provinces, western Inner Mongolia, and the adjacent southwestern area of Mongolia; the Gobi Desert in southern Mongolia and the adjoining area of northern Inner Mongolia; sandy lands and deserts around the middle reaches of the Yellow River; and the area rimming the Taklimakan Desert) were the main contributors to long-lived mineral dusts in northern China and Mongolia. Of these dust production areas, sandy lands and stony deserts, rather than the sandy deserts of Inner Mongolia and Mongolia, were found to be the dominant dust sources, accounting for more than 75% of regional dust emission events. Dust events in the Taklimakan Desert were often local phenomena, although they could also be transported eastward if they were uplifted high enough to escape the enclosing topographic highs. Dust sources in northwestern China are mainly alluvial fans and dry lake and river beds. Success in identifying the sources and trajectories of Asian dust storms would guide future ground-based research and steppe degradation countermeasures and help reduce the uncertainties in modern modeling of Asian dust. [Copyright &y& Elsevier]

Abstract: ZnO thin films were grown on (100) p-Si substrates by Photo-assisted Metal Organic Chemical Vapor Deposition (PA-MOCVD) using diethylzinc (DEZn) and O2 as source materials and tungsten–halogen lamp as a light source. The effects of tungsten–halogen lamp irradiation on the surface morphology, structural and optical properties of the deposited ZnO films have been investigated by means of atomic force microscope (AFM), X-ray diffraction and photoluminescence (PL) spectra measurements. Compared with the samples without irradiation, the several characteristics of ZnO films with irradiation are improved, including an improvement in the crystallinity of c-axis orientation, an increase in the grain size and an improvement in optical quality of ZnO films. These results indicated that light irradiation played an important role in the growth of ZnO films by PA-MOCVD. [Copyright &y& Elsevier]

Abstract: SiC whisker reinforced MoSi2 composite powder has been successfully synthesized by “chemical oven” combustion synthesis method. The mixtures of Si and Ti were ignited as chemical oven. XRD result shows that the combustion product is mainly composed of MoSi2 and SiC phases. SEM photo and EDS result show that SiC whisker is formed during this process. [Copyright &y& Elsevier]

Abstract: TiN/Y-(α/β)-sialon ceramics with good mechanical properties were successfully obtained by pressureless sintering from SHS powder. XRD results showed the main phases of SHS powder to be α-sialon (68.5wt.%) and β-sialon (29.3wt.%). The microhardness, flexural strength and fracture toughness of the pressureless densified sialon ceramic reached 14.22GPa, 651MPa and 5.09MPam1/2, respectively. [Copyright &y& Elsevier]

Abstract: Al2O3/LaPO4 composites were fabricated by pressureless sintering in N2 atmosphere. The effect of sintering temperature and sintering time on densification was examined, as well as the dependence of mechanical properties and microstructure on LaPO4 content. Provided the ratio of La/P was close to 1:1, no reactions were observed after 2h at 1650°C in N2 atmosphere. The 30wt.% LaPO4/Al2O3 composites could be machined using cemented carbide drills as those pressureless sintered in air. LaAl11O18 was formed when the composite was sintered at 1700°C for 1h in N2 atmosphere, and the composites were not machinable. [Copyright &y& Elsevier]

Abstract: In metalorganic vapor-phase epitaxy (MOVPE) growth of III–V semiconductor compounds and device structures, arsine (AsH3) and phosphine (PH3) are normally used as group V precursors and hydrogen is used as the carrier gas, which is very toxic and has safety hazard. In this contribution, MOVPE growths of Al-free 808nm high power diode lasers by using metalorganic (MO) group V sources, TBAs and TBP, and nitrogen as carrier gas has been reported. InGaAsP/InGaP/GaAs single quantum well (SQW) high power laser structure emitting at 808nm has been adopted to characterize the material quality. Broad area stripe lasers with the stripe width of 150μm have been fabricated from the wafers grown by the MOVPE using MO group V sources. Lasing of the device with threshold current density of 506A/cm2 has been successfully achieved. [Copyright &y& Elsevier]

Abstract: The biochemical role of guanine nucleotide exchange factors (GEFs) in catalyzing small GTPase GDP–GTP exchange is thought to be twofold: stimulation of GDP dissociation and stabilization of a nucleotide-free GTPase intermediate. Here we report that TrioN, a Dbl family GEF, activates Rac1 by facilitating GTP binding to, as well as stimulating GDP dissociation from, Rac1. The TrioN-catalyzed GDP dissociation is dependent upon the structural nature and the concentration of free nucleotide, and nucleotide binding serves as the rate-limiting step of the GEF reaction. The TrioN-stimulated nucleotide exchange may undergo a novel two nucleotide-one G-protein intermediate involving two cryptic subsites on Rac1 induced by the GEF, with one subsite contributing to the recognition of the β/γ phosphates of the incoming GTP and another to the binding of the guanine base of the leaving GDP. We propose that the Rac GEF reaction may proceed by competitive displacement of bound GDP by GTP through a transient intermediate of GEF–[GTP–Rac–GDP]. [Copyright &y& Elsevier]

Abstract: The corrosion behavior of Y-(α + β)-sialon/TiN materials in hot hydrochloric acidic solutions (80°C) was studied. The effect of TiN on the corrosion behavior of Y-(α + β)-sialon/TiN materials was investigated. The results revealed that the introduction of TiN accelerate the corrosion. With the increasing of TiN content, the α-sialon content on the final composition decreased and more yttrium remains on the grain boundary phase. Therefore, the corrosion was severed due to the formation of soluble YCl3. [Copyright &y& Elsevier]

Ras GTPases function as binary switches in the signaling pathways controlling cell growth and differentiation by cycling between the inactive GDP-bound and the active GTP-bound states. They are activated through interaction with guanine nucleotide exchange factors (ClEFs) that. catalyze the exchange of bound GDP with cytosotic GTP. In a conventional scheme, the biochemical roles of GEFs are postulated as stimulating the release of the bound GDP and stabilizing a nucleotide-free transition state of Ras. Herein we have examined in detail the catalyzed GDP/GTP exchange reaction mechanism by a Ras specific GEF, GRF1. In the absence of free nucleotide, GRF1 could not efficiently stimulate. GDP dissociation from Ras. The release of the Ras-bound GDP was dependent upon the concentration and the structure of the incoming nucleotide, in particular, the hydrophobicity of the β and γ phosphate groups, suggesting that the GTP binding step is a prerequisite for GDP dissociation, is the rate-limiting step. in the GEF reaction, or both. Using a pair of fluorescent guanine nucleotides (N-methylanthrartiloyl GDP:and 2',3'- O-(2,4,6-trinitrocyclohexadienylidene)-GTP) as donor and acceptor probes, we were, able to detect fluorescence resonance energy transfer between the incoming GTP and the departing GDP on Ras under controlled kinetic conditions, providing evidence that there may exist a novel intermediate' of the GEF- Ras complex that transiently binds to two nucleotides simultaneously. Furthermore, we found that Ras was capable of binding pyrophosphate (PPi) with a dissociation constant of 26 μM and :that PPi. and GMP, but neither alone, synergistically potentiated the GRF1-stimulated GDP dissociation from Ras. These results strongly support a GEF reaction mechanism by which nucleotide exchange `Occurs on Ras through a direct GTP/GDP displacement model. [ABSTRACT FROM AUTHOR]

The small GTPase Rac1 has emerged as an important regulator of cell survival and apoptosis, but the mechanisms involved are not completely understood. In this report, constitutively active Rac1 is shown to stimulate the phosphorylation of the Bcl-2 family member Bad, thereby suppressing drug-induced caspase activation and apoptosis in human lymphoma cells. Rac1 activation leads to human Bad phosphorylation specifically at serine-75 (corresponding to murine serine-112) both in vivo and in vitro. Inhibition of constitutive and activated Rac1-induced Bad phosphorylation by a cell-permeable competitive peptide inhibitor representing this Bad phosphorylation site sensitizes lymphoma cells to drug-induced apoptosis. The data show further that endogenous protein kinase A is a primary catalyst of cellular Bad phosphorylation in response to Rac activation, while Akt is not involved. These findings define a mechanism by which active Rac1 promotes lymphoma cell survival and inhibits apoptosis in response to cancer chemotherapy drugs. [ABSTRACT FROM AUTHOR]

This paper presents the preparation of β-Si3N4 rod-like crystals that have an average aspect ratio of ∼10 by combustion synthesis of the mixture of Si, α-Si3N4 and Y2O3 under 5 MPa nitrogen pressure. By using a quenching device, the growth morphology of β-Si3N4 rod-like crystals was observed and it is concluded that the growth mechanisms result from the synergy of VLS (vapor–liquid–solid) and VS (vapor–solid). [Copyright &y& Elsevier]

Deals with a study which analyzed the detectivity, the quantum efficiency and the zero-bias resistance-area product in N-p and P-n GaSb/Ga...In...As...Sb infrared detectors. Auger mechanism and radiative mechanism; Generation-recombination mechanism; Tunneling mechanism; Quantum efficiency; Results and discussion; Conclusion.

A novel WO x -based memristor with Ti nano-island arrays was developed in this study. A 100 nm thick Pt bottom electrode was deposited, and an ultrathin anodic aluminum oxide (AAO) template was used to obtain the Ti nano-island arrays. The WO x /Ti nano-island (NI)/Pt devices were prepared by magnetron sputtering using a WO y (y=2.7–2.9) target to obtain a 30 nm deposition layer of WO x. Scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and semiconductor analysis confirmed that the WO x -based memristor could be successfully produced with a highly ordered Ti nano-island array. The size and density of the NIs could be controlled by selecting the aperture of the AAO template. The oxygen interaction between the Ti nano-islands and WO x led to the creation of oxygen vacancies in their vicinity, resulting in the formation of an oxygen vacancy conductive filament (CF) without the need for a forming process. NIs tend to strengthen the electric field along the bias voltage direction, fostering the generation of the CF. The absolute values of V SET and V RESET were about 0.19 V and 0.69 V, respectively. Compared with the devices without the Ti NI arrays, the variation coefficients of V SET and V RESET of the WO x /Ti NI/Pt devices were reduced by about 84.9% and 83.7%, respectively. With smaller and more concentrated V SET and V RESET , the WO x /Ti NIs/Pt device showed a significantly improved switching stability. [Display omitted] [ABSTRACT FROM AUTHOR]

Due to their unique electrical performance and simple structure, memristors exhibit excellent application prospects for future information technology. In this work, we fabricated Pt/Ti/AlOx/CeOx/Pt memristors demonstrating electroforming-free bipolar resistive switching behavior with low operating voltage (−1 to 1 V), stable endurance, and retention. Space-charge limited conduction (SCLC) as well as the formation and rupture of conductive filaments are responsible for the resistive switching behavior. Increasing the magnitude of the RESET voltage could generate multistate resistive switching. We studied the synaptic characteristics of the device by obtaining multilevel conductance states and investigating the relationship between the device resistance, pulse amplitude, pulse width, and pulse number. By applying programmed pre and postsynaptic spiking pulses, spike-timing dependent plasticity was observed. This study shows that the device is suitable for multivalue storage and can be used as an electronic synapse device in artificial neural networks. [ABSTRACT FROM AUTHOR]

Background: How much scientific evidence is there to show that stem cell therapy is sufficient in preclinical and clinical studies of spinal cord injury before it is translated into clinical practice? This is a complicated problem. A single, small-sample clinical trial is difficult to answer, and accurate insights into this question can only be given by systematically evaluating all the existing evidence.Methods: The PubMed, Ovid-Embase, Web of Science, and Cochrane databases were searched from inception to February 10, 2022. Two independent reviewers performed the literature search, identified and screened the studies, and performed a quality assessment and data extraction.Results: In total, 62 studies involving 2439 patients were included in the analysis. Of these, 42 were single-arm studies, and 20 were controlled studies. The meta-analysis showed that stem cells improved the ASIA impairment scale score by at least one grade in 48.9% [40.8%, 56.9%] of patients with spinal cord injury. Moreover, the rate of improvement in urinary and gastrointestinal system function was 42.1% [27.6%, 57.2%] and 52.0% [23.6%, 79.8%], respectively. However, 28 types of adverse effects were observed to occur due to stem cells and transplantation procedures. Of these, neuropathic pain, abnormal feeling, muscle spasms, vomiting, and urinary tract infection were the most common, with an incidence of > 20%. While no serious adverse effects such as tumorigenesis were reported, this could be due to the insufficient follow-up period.Conclusions: Overall, the results demonstrated that although the efficacy of stem cell therapy is encouraging, the subsequent adverse effects remain concerning. In addition, the clinical trials had problems such as small sample sizes, poor design, and lack of prospective registration, control, and blinding. Therefore, the current evidence is not sufficiently strong to support the clinical translation of stem cell therapy for spinal cord injury, and several problems remain. Additional well-designed animal experiments and high-quality clinical studies are warranted to address these issues. [ABSTRACT FROM AUTHOR]

Climate change has led to shifts in species distribution and become a crucial factor in the extinction of species. Increasing average temperatures, temperature extremes, and unpredictable weather events have all become a part of a perfect storm that is threatening ecosystems. Higher altitude habitats are disproportionately affected by climate change, and habitats for already threatened specialist species are shrinking. The Siberian ibex, Capra sibirica, is distributed across Central Asia and Southern Siberia and is the dominant ungulate in the Pamir plateau. To understand how climate change could affect the habitat of Siberian ibex in the Taxkorgan Nature Reserve (TNR), an ensemble species distribution model was built using 109 occurrence points from a four-year field survey. Fifteen environmental variables were used to simulate suitable habitat distribution under different climate change scenarios. Our results demonstrated that a stable, suitable habitat for Siberian ibex was mostly distributed in the northwest and northeast of the TNR. We found that climate change will further reduce the area of suitable habitat for this species. In the scenarios of RCP2.6 to 2070 and RCP8.5 to 2050, habitat loss would exceed 30%. In addition, suitable habitats for Siberian ibex will shift to higher latitudes under climate change. As a result, timely prediction of the distribution of endangered animals is conducive to the conservation of the biodiversity of mountain ecosystems, particularly in arid areas. [ABSTRACT FROM AUTHOR]

In this paper, we present a fully pipelined and semi-parallel channel convolutional neural network hardware accelerator structure. This structure can trade off the compute time and the hardware utilization, allowing the accelerator to be layer pipelined without the need for fully parallelizing the input and output channels. A parallel strategy is applied to reduce the time gap in transferring the output results between different layers. The parallelism can be decided based on the hardware resources on the target FPGA. We use this structure to implement a binary ResNet18 based on the neural architecture search strategy, which can increase the accuracy of manually designed binary convolutional neural networks. Our optimized binary ResNet18 can achieve a Top-1 accuracy of 60.5% on the ImageNet dataset. We deploy this ResNet18 hardware implementation on an Alphadata 9H7 FPGA, connected with an OpenCAPI interface, to demonstrate the hardware capabilities. Depending on the amount of parallelism used, the latency can range from 1.12 to 6.33 ms, with a corresponding throughput of 4.56 to 0.71 TOPS for different hardware utilization, with a 200 MHz clock frequency. Our best latency is 8 × lower and our best throughput is 1. 9 × higher compared to the best previous works. The code for our implementation is open-source and publicly available on GitHub at https://github.com/MFJI/NASBRESNET. [ABSTRACT FROM AUTHOR]

Iron oxide nanoparticles (IONs) with good water dispersibility were prepared by the thermal decomposition of iron acetylacetonate (Fe(acac)3) in the high-boiling organic solvent polyethylene glycol (PEG) using polyethyleneimine (PEI) as a modifier. The nucleation and growth processes of the crystals were separated during the reaction process by batch additions of the reaction material, which could inhibit the nucleation but maintain the crystal growth, and products with larger particle sizes and high saturation magnetization were obtained. The method of batch addition of the reactant prepared IONs with the largest particle size and the highest saturation magnetization compared with IONs reported using PEG as the reaction solvent. The IONs prepared by this method also retained good water dispersibility. Therefore, these IONs are potentially suitable for the magnetic separation of cells, proteins, or nucleic acids when large magnetic responses are needed. [ABSTRACT FROM AUTHOR]

Examines the regulation of Rhoa GTP hydrolysis by GTPAse-activating proteins. Materials and methods used in the Details on how GTPase activites were achieved; Results of experiments.

Some modified AGE methods for the convection–diffusion equation are developed in this paper. Firstly, there is a treatment on the convection term in the equation which is different from that in the AGE method by Evans and Abdullah (1985). Secondly, upwind-type schemes are used for the convection dominated diffusion problems. All the modified AGE methods in the paper are unconditionally stable. The numerical example is given to show the effectiveness of the methods. The methods have the obvious property of parallelism. © 1998 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The Guanting Pb–Zn deposits in the Jianshui area, southern Yunnan Province, SW China, are located in the conjunction of the Yangtze Block, Cathaysian Block and Sanjiang Block, and they belong to part of the Sichuan-Yunnan-Guizhou (SYG) Pb–Zn metallogenic province. The Pb–Zn orebodies occur in basaltic and limestone breccia at the interfaces between the Maokou limestone and Emeishan basalt. Here, we use zircon U–Pb dating, Rb–Sr dating, trace elements and S isotope data of sulfides to constrain the ages and genesis of deposits. Petrological investigations reveal two main stages of mineralization. Early-stage sphalerites yield a Rb–Sr age of 251.1 ± 8.5 Ma, and it is contemporaneous with the Guanting basalt within the range of error, which has a concordant age of 247.3 ± 4.2 Ma. This metallogenic age indicates that early-stage mineralization may be related to Emeishan volcanic hydrothermal activity. Initial value of 87Sr/86Sr (0.709) and rare earth elements (REE) patterns of minerals suggest that ore-forming materials were likely derived from mixed mantle-crust sources, and paleo-seawater participated in deposition of Pb–Zn ore. There are two peaks of sulfur isotope (δ34S) in the Huangtian and Xinzhai deposits. The δ34S of early-stage sulfide is concentrated at + 1.1‰ VCDT to + 3.9‰ VCDT, suggesting that the sulfur was directly supplied by basaltic volcanic activity. Late-stage colloidal sulfides have δ34S ranging from + 6‰ VCDT to + 9‰ VCDT, suggesting marine sulfur origin, and that reduced sulfur derived from carbonate strata by thermochemical sulfate reduction (TSR). According to the geochemical characteristics, geochronology and regional geodynamic setting, we assume that early-stage mineralization in the Guanting Pb–Zn deposits is Emeishan volcanic hydrothermal mineralization, and late-stage mineralization is similar with Mississippi Valley-type (MVT) deposit. Our results provide new evidence for understanding hydrothermal mineralization associated with the Emeishan flood basalts in the SYG area. [ABSTRACT FROM AUTHOR]

Abstract: Water-soluble superparamagnetic Fe3O4 nanoparticles with an average diameter of 9.5±1.7nm were synthesized by thermal decomposition of Fe(acac)3 in MPEG. MPEG was used as solvent, reducing agent, and modifying agent in this reaction. An obvious advantage of this approach is that no further reducing agent and surfactants are required. The products were characterized by powder X-ray diffraction, transmission electron microscopy and fourier transform infrared spectroscopy. The magnetic properties were evaluated using a superconducting quantum interference device. The elevating temperature procedures influence the sizes and the size distribution of the magnetite (Fe3O4) nanoparticles. A tentative mechanism of the formation of Fe3O4 nanoparticles is proposed to explain the formation of the magnetite nanoparticles. [Copyright &y& Elsevier]