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Improving tumor accumulation and delivery efficiency is an important goal of nanomedicine. Neutrophils play a vital role in both chemically mediating inflammatory response through myeloperoxidase (MPO) and biologically promoting metastasis during inflammation triggered by the primary tumor or environmental stimuli. Herein, a novel theranostic nanomedicine that targets both the chemical and biological functions of neutrophils in tumor is designed, facilitating the enhanced retention and sustained release of drug cargos for improved cancer theranostics. 5-hydroxytryptamine (5-HT) is equipped onto nanoparticles (NPs) loaded with photosensitizers and Zileuton (a leukotriene inhibitor) to obtain MPO and neutrophil targeting NPs, denoted as HZ-5 NPs. The MPO targeting property of 5-HT modified NPs is confirmed by noninvasive positron emission tomography imaging studies. Furthermore, photodynamic therapy is used to initiate the inflammatory response which further mediated the accumulation and retention of neutrophil targeting NPs in a breast cancer model. This design renders a greatly improved theranostic nanomedicine for efficient tumor suppression, and more importantly, inhibition of neutrophil-mediated lung metastasis via the sustained release of Zileuton. This work presents a novel strategy of targeting neutrophils for improved tumor theranostics, which may open up new avenues in designing nanomedicine through exploiting the tumor microenvironment.

Synthetic ion channels represent a new approach to mimicking natural ion channels and developing therapeutic drugs to restore ion channel dysfunction. The large superfamily of transient receptor potential (TRP) channels involved in numerous biological processes is an important and potent therapeutic target for various human diseases. In the present study, a synthetic peptide whose sequence is from the fourth transmembrane segment of TRPV4 is found that is capable of self-assembling into potassium (K+)-like ion channels designated as TRP-PK1 in the membranes of liposomes and live cells. TRP-PK1 effectively mediates K+ flow across the cell membrane to regulate the membrane potential. TRP-PK1 is also able to relax agonist-induced vessel contraction and regulate the resting blood pressure by hyperpolarizing the vascular smooth muscle cell membrane potential. TRP-PK1 represents a novel lead compound for mimicking K+ channels and treating hypertension, heart rate disorder and other K+ channel dysfunction-induced diseases. The present study also sheds new light onto the mimic ion channel function and the significant utilization of natural biological sources.

Heteroatom-doped carbon dots (CDs), due to their excellent photoluminescence (PL) properties, attracted widespread attention recently and demonstrated immense promise for diverse applications, particularly for biological applications. The objective of this feature article is to provide a comprehensive overview of the recent progress in the research and development of heteroatom-doped CDs and a detailed description of the influence of single or co-doping heteroatoms on their PL behavior. The most recent understanding and critical insights into the PL mechanism of heteroatom-doped CDs are also highlighted. Moreover, potential bio-related applications of heteroatom-doped CDs in biosensing, bioimaging, and theranostics are also reviewed. This state-of-the-art review will provide a platform for understanding the intricate details of heteroatom-doped CDs, a summary of the latest progress in the field, and related applications in biology and is expected to inspire further developments in this exciting class of materials.

Platinum (Pt)-based drugs including cisplatin, carboplatin and oxaliplatin have been widely used as first-line anticancer regimens due to their excellent anticancer efficacy. However, the clinical application of these drugs is greatly limited due to their side effects and drug resistance. In this study, an antitumor drug delivery system based on carboplatin prodrug loading Fe

A new FRET probe has been prepared for ratiometric fluorescence detection of hydroxyl radicals. It has been successfully used for detecting mitochondria-localized drug activation in living cells and imaging endogenous hydroxyl radicals in zebrafish gastrointestinal (GI) tracts under normal culturing conditions.

Triclosan (TCS) has been widely used as an antibacterial agent for the last several decades in personal care products. The toxicological effect of TCS has attracted more and more attention of researchers. The purpose of this study is to evaluate the cytotoxic effects of TCS in HepG2 cells and to elucidate the molecular mechanism focusing on regulation of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/forkhead box O (FoxO) pathway in the glycolytic metabolism. In this study, we evaluated the adverse effect of TCS exposure on cell viability, reactive oxygen species (ROS) generation, superoxide dismutase (SOD) activity and mitochondrial membrane potential (MMP). In addition, the glycolysis process in HepG2 cells exposed to TCS was examined in terms of glucose consumption, lactate production and ATP generation. Furthermore, Affymetrix Human U133 plus 2.0 gene chips and gene function enrichment analysis were conducted to screen differential expression genes (DEGs) and potential signaling pathway. Expressions of the glycolysis-related proteins were measured and quantified with Western Blotting. The results showed that TCS could suppress the cell viability, induce oxidative stress, and cause mitochondrial damage. In addition, TCS exposure promoted the glycolysis process, as manifested by accelerated conversion of glucose to lactate and increased energy release. Western Blotting results confirmed that the expression levels of glycolysis related proteins were significantly elevated. The PI3K/Akt/FoxO pathway was identified to play a pivot role in TCS-induced glycolysis, which was further confirmed by inhibitor tests using specific inhibitors LY294002 and MK2206. In general, TCS can induce oxidative stress, cause oxidative damages and promote glycolysis in HepG2 cells, which was mediated by the PI3K/Akt/FoxO pathway. Keywords: Glycolysis, Molecular mechanism, PI3K/Akt/FoxO pathway

Fetal exposure to sevoflurane induces long-term cognitive impairment. Histone acetylation regulates the transcription of genes involved in memory formation. We investigated whether sevoflurane exposure during late-pregnancy induces neurocognitive impairment in offspring, and if this is related to histone acetylation dysfunction. We determined whether the effects could be reversed by an enriched environment (EE). Pregnant rats were exposed to 2.5% sevoflurane or control for 1, 3, or 6 h on gestational day 18 (G18). Sevoflurane reduced brain-derived neurotrophic factor (BDNF), acetyl histone H3 (Ac-H3), and Ac-H4 levels and increased histone deacetylases-2 (HDAC2) and HDAC3 levels in the hippocampus of the offspring on postnatal day 1 (P1) and P35. Long-term potentiation was inhibited, and spatial learning and memory were impaired in the 6-h sevoflurane group at P35. EE alleviated sevoflurane-induced cognitive dysfunction and increased hippocampal BDNF, Ac-H3, and Ac-H4. Exposure to 2.5% sevoflurane for 3 h during late-pregnancy decreased hippocampal BDNF, Ac-H3, and Ac-H4 in the offspring but had no effect on cognitive function. However, when the exposure time was 6 h, impaired spatial learning and memory were linked to reduced BDNF, Ac-H3, and Ac-H4, which could be reversed by EE.

The improvement of electricity production for water evaporation-driven generators (WEGs) remains a challenge. Herein, two types of WEGs were designed to study the resistance matching for improving the electricity production using the method of nanoarchitectonics. One type of reduced graphene oxide/carbon nanotube (RGO/CNT) WEG was constructed using RGO with adjustable resistances as working material and CNTs with fixed resistance as electrode material. The other type of graphene oxide (GO)/RGO WEG was constructed using RGO with adjustable resistance as electrode material and GO with fixed resistance was used as working material. The open circuit voltage of RGO/CNT increased from 15 to 56 mV and then decreased to 22 mV with increasing RGO resistance. The short circuit current of RGO/CNT also first increased and then decreased. The performance of GO/RGO was similar with that of RGO/CNT. Typically, the RGO/CNT and GO/RGO WEG showed the highest performance when the working material to electrode material resistance ratio was 2272 and 2365, respectively. It showed that the best resistance ratio of working material to electrode material was in the range of 2000–2500, which helped to improve about 2–5 times of electricity efficiency in the WEG. The present work provides a new direction for optimizing performance of WEGs.

In this paper, the thermal vibration damage of rigid polyurethane foam (RPUF) under the action of oxygen, temperature and vibration was systematically studied by the combination of experiment and finite element analysis. The damage degree of RPUF was evaluated by their compressive mechanical properties and energy absorption properties. The results of Fourier infrared spectrum (FTIR) and nuclear magnetic resonance (13C NMR) showed that the thermal degradation of the carbamate group was the main chemical failure process of RPUF in the aerobic/anaerobic high temperature environment. Particularly, the thermal oxidative degradation of ether bonds occurred in an aerobic high temperature environment. It was also proved by the simulation results of Discrete Fourier Transform (DFT). Compression experiments showed that with the increase of temperature, the compressive mechanical properties and energy absorption properties of the RPUF gradually decrease until they reach the minimum value at 150 °C.These compressive performances of the thermal vibration group (treated in thermal vibration environment) were lower than the corresponding heat treatment group (treated in heat treatment environment). In the 50–300Hz, 550–800Hz and 1050–1300Hz, the failure degree of the low-frequency stage (50–300Hz) is also the highest among the thermal vibration group. At this time, the elastic modulus and compression yield strength of the aerobic 150 °C thermal vibration group were 14.47 MPa and 1.17 MPa, respectively, which were 19.6% and 9.3% lower than the anaerobic 150 °C thermal vibration group.

In recent years, the unprecedented advances of biomedical nanotechnology have spurred the development of drug delivery systems (DDSs) based on multifarious nanomaterials in disease treatment and diagnostic purposes, which simultaneously boost the therapeutic outcome and circumvent the side effects. Among these, mesoporous silica nanoparticles (MSNs) are acknowledged as one of the most promising candidates for cargo delivery. Their remarkable intrinsic features, including size and porosity tunability, large surface area, high pore volume, versatile surface functionality as well as biocompatibility, have arouse tremendous research of MSNs as multifunctional delivery platforms. In particular, intelligent MSNs-based controlled delivery systems with stimuli-responsive characteristics hold great promise in personalized precision medicine in clinical applications. Notably, benefiting from the tunable pore size and diversified surface chemistry, MSNs-based systems can transport a variety of therapeutic agents such as small-molecule drug, gene, peptide, as well as protein, which have tremendous potential to treat diverse types of diseases, including carcinoma, bacterial infections (infectious diseases), diabetes, bone disorders, Alzheimer’s disease, etc. In this review, a brief overview of MSNs and their features, together with the discussions on engineering of stimuli-responsive MSNs-based systems for on-demand payload delivery is presented. Further, the application of the state-of-the-art MSNs-based delivery systems in multifarious disease therapeutics (not limited to carcinoma) with a particular focus on recent studies is summarized. Finally, the clinical translation issues encountered by these delivery platforms and their possible solutions together with future perspectives of MSN-based systems in clinics are also mentioned.

Due to the aggregation-caused quenching effect and near-infrared I poor penetration capabilities of common fluorescent molecules, their applications in visualized imaging and photoactivated treatment are limited. Therefore, new near-infrared II (NIR-II) molecule (named TST), which had the abilities of aggregation-induced emission (AIE) and photothermal therapy are synthesized. Moreover, in order to further improve its fluorescent yield and therapeutic effect, camptothecin prodrug (CPT-S-PEG) and novel immune checkpoint inhibitor AZD4635 are used to co-assemble with TST into nanoparticles for drug delivery. On account of the strong interaction of camptothecin and TST, the intramolecular rotation of TST is limited, thereby inhibiting non-radiation attenuation and promoting fluorescence generation when the nanoparticles are intact. As nanoparticles uptake by cancer cells, redox sensitive CPT-S-PEG is degraded and the nanoparticles disintegrate. The released TST enhances non-radiative attenuation and expedites photothermal conversion because of the removal of the constraint of camptothecin. Furthermore, photothermal therapy induces immunogenic cell death of cancer cells and releases abundant ATP into the tumor microenvironment to recruit immune cells. However, superfluous ATP is converted into immunosuppressive adenosine through the CD39-CD73-A2AR pathway. The AZD4635 released by photothermal disintegration of the nanoparticles just blocks this pathway timely, achieving favorable synergistic effect of photothermal therapy, chemotherapy, and immunotherapy.

Synthesis of magnetic nanoparticles (MNPs) is one of the most active research areas in advanced materials. MNPs that have magnetic properties and other functionalities have been demonstrated to show great promise in nanomedical applications. This review summarizes the current MNPs preparation, functionalization and stabilization methods. It also analyzes the detailed features of MNPs. And furthermore it highlights some actual case analyses of these MNPs for disease therapy, drug delivery, hyperthermia, bioseparation and bioimaging applications.

A novel full-digital multibeam array with wide scanning angle and enhanced beam gain is proposed for millimeter-wave massive multiple-input multiple-output applications. The array consists of 16 dual exponentially tapered slot antenna (DETSA) elements. Each element is integrated with a radio frequency receiver, an intermediate frequency chain, and an analog-to-digital converter (ADC). The H-plane radiation pattern of the proposed DETSA is very wide to enable the beam scanning in the azimuth plane. The beam gain is further enhanced by employing a 1-D multilayered planar lens that transforms the spherical wave into a plane wave in the E-plane for increasing the beam gain and keeping the phase compensation unaltered in the H-plane. Meanwhile, the planar lens is optimized to guarantee the wide scanning angle. In addition, all the signals received by the 16 independent channels are converted to a digital signal via ADC simultaneously and then used for synthesizing the multibeam patterns in the digital domain. Furthermore, the calibration and the verification of the synthesizing weights are discussed in detail. The measured results show that a scanning coverage of ±40° in the H-plane (or in horizontal plane) and an estimated maximum gain of 24.8 dBi with a gain tolerance of 3 dB can be achieved by the proposed 16-element array with a 1-D lens.

The tensile failure mechanism of carbon–aramid hybrid fibers/epoxy sandwich structure laminates was investigated by using experimental and finite element methods. Double curing agents, triarylsulfonium hexafluoroantimonates and triethylene tetramine with a mass ratio of 4:15 were introduced into the laminates. Sandwich structure laminates, with different proportions of hybrid fibers, were cured by UV-initiated anion/cationic dual curing technique. The results showed that the synergetic curing effects of two curing agents were observed under UV irradiation, leading to the better curing of the system, which further plays a positive influence on the mechanical performance. The tensile properties and failure mechanism of the laminates depended on the stacking sequence and fiber volume fractions of the layer structures. The interplay hybrid laminates, containing three alternate plies with fiber contents of 67.7 vol%, presented the optimal tensile performance, and its tensile strength and modulus were 0.82 GPa and 22.09 GPa, respectively. The fracture morphologies revealed that pull-out and debonding of fibers were the main failure mechanism of hybrid laminates. The performance of sandwich structure laminates was determined by the load-carrying capacity of carbon fiber and load-transferring capacity of the aramid fiber and adhesive. The finite element model based on experiments was established to simulate the stress state and failure mechanism of sandwich laminates. The results demonstrated that the stress was better transferred into carbon fibers from the aramid fibers and adhesive, and the relative error rate of maximum stress from finite element analysis and experimental results was less than 5%, which were in reasonable agreement with the experimental results.

A peculiar and regular diffraction pattern is recorded while using either a color or a monochrome charge-coupled device (CCD) camera to capture the image of the micro air plasma produced by femtosecond laser pulses. The diffraction pattern strongly disturbs the observation of the air plasma, so the origin and eliminating method of these diffraction patterns must be investigated. It is found that the Fourier transform of the periodic surface structure of either the mask mosaic of the color CCD or the pixel array of the monochrome CCD is responsible for the formation of the observed pattern. The residual surface reflection from the protection window of a CCD camera plays the essential role in forming the interesting two-dimensional diffraction spots on the same CCD sensor. Both experimental data and theoretical analyses confirm our understanding of this phenomenon. Therefore removing the protection window of the CCD camera can eliminate these diffraction patterns.

A 2 kW/28.5 kJ superconducting flywheel energy storage system (SFESS) with a radial-type high-temperature superconducting (HTS) bearing was set up to study the electromagnetic and rotational characteristics. The structure of the SFESS as well as the design of its main parts was reported. A mathematical model based on the finite element method (FEM) was established to research the electromagnetic characteristics of the HTS bearing during the levitation process, which show that a part of the magnetic flux penetrates into the edge of the HTS bulks and then goes back to the opposite pole of the permanent magnet rotor (PMR). The induced current mainly distributes in the edge of the HTS bulks, indicating that larger force acts on the edge part of the HTS bulks and probably causes them to crack. The free rotations of the rotor at different steady-state speeds of 2500–5000 rpm and its radial vibration were displayed. The induced voltage of the stator winding of the motor in this process was analyzed. The rotational characteristics are related to the vibration of the rotor. Below the resonant frequency, the vibration increases significantly with the speed. Enhancing the radial stiffness to limit the vibration amplitude of the rotor is an effective approach to improve the speed.

Recently we found that direct exposure of human umbilical vein endothelial cells (HUVECs) to multi-walled carbon nanotubes (MWCNTs) might induce toxicological responses through the modulation of ER stress gene expression, but whether this signal could be transferred from other cells to endothelial cells (ECs) is unknown. This study investigated the toxicity of pristine and carboxylated MWCNTs to HUVECs and alveolar-endothelial co-culture, the later of which could mimic the possible signaling communications between ECs and MWCNT exposed alveolar cells. The results showed that direct contact with high levels of MWCNTs induced cytotoxicity and modulated expression of genes associated with ER stress (HSPA5, DDIT3 and XBP-1s) and autophagy (BECN1 and ATG12) both in A549-THP-1 macrophages cultured in the upper chambers as well as HUVECs. However, most of these responses were minimal or negligible in HUVECs cultured in the lower chambers. Moreover, significantly increased cytokine release (interleukin-6 and soluble vascular cell adhesion molecule-1) was only observed in MWCNT exposed HUVECs (p 0.01) but not HUVECs cultured in the lower chambers (p 0.05). The minimal or even absent response was likely due to relatively low translocation of MWCNTs from upper chambers to lower chambers, whereas A549-macrophages cultured in the upper chambers internalized large amount MWCNTs. The results indicated that ER stress-autophagy signaling might not be able to transfer from alveolar cells to endothelial cells unless sufficient MWCNTs are translocated.

A planar circularly polarized substrate integrated waveguide (SIW) stacked patch antenna array consisting of four sequential-rotation (SR) subarrays is presented for $Ka$ -band applications. Antenna element is realized based on a pair of stacked cavities by the combination of a driven patch layer and a parasitic patch layer, which are formed by a shorted square patch and multiple identical stacked square patches, respectively. Each subarray consisting of two pairs of elements, excited by a coplanar waveguide (CPW) network with four metallic vias, is well matched to a novel SIW SR feeding network. A narrow transverse coupling slot, a semiopening resonant cavity, two pairs of inductive vias, and an inductive window are introduced in the SIW-based feeding network to implement functions of phase shifter, impedance matching, and power divider in the two layers. By employing the proposed SR feeding network, the CPW network, and the four subarrays, the excellent performance of the array is realized. To verify the design, a prototype is fabricated and measured, which demonstrates a −10 dB impedance bandwidth of 29.6%, a 3 dB axial ratio bandwidth of 25.4%, and a peak gain of 20.32 dBic.

316 L N L-shape stainless steel is used in ITER Side Correction Coil (SCC) box. Finite Element Method (FEM) simulation is adopted to analyze metal flow characteristics, forecast extrusion force and ascertain extruder tonnage of 316 L N L-shape stainless steel during extrusion process. Based on simulation results, 316 L N round forged billet is used to manufacture L-shape stainless steel by extrusion process. The extrusion process includes circular furnace preheating, induction heating, glass lubrication, mould design and deformation design. 316 L N L-shape stainless steel is manufactured by Φ360 mm circular container and 60 MN horizontal extruder successfully. Mechanical properties and microstructure of 316 L N L-shape stainless steel all accord with the requirements of ITER SCC box. SCC box case is manufactured by bending, machining and welding processes. X-ray, ultrasonic testing (UT) and penetration testing (PT) are used to inspect the welding quality of SCC box case. The SCC box case passes the acceptance of ITER project expert group, this result verifies that the extrusion process and manufacture process are reasonable and feasible.

Monosaccharides are important tracers of pollution aerosol from biomass burning. Air sampling of monosaccharides is often conducted using active samplers. However, applicability of sampling monosaccharides using polyurethane foam passive air samplers (PUF-PASs) has not been investigated, since passive air samplers are often applied to monitor semivolatile organic contaminants in large scale and remote area. Our study successfully collected atmospheric monosaccharides using PUF-PASs, providing a valuable tool for monosaccharides sampling. PUF-PAS sampling rates for individual monosaccharides were calibrated using an active sampler for 92 days, and were 1.1, 1.5, and 1.1 m3/d for levoglucosan, mannosan, and galactosan, respectively. Degradation of monosaccharides in PUF-PAS was demonstrated to be negligible by spike test of 13C-labeled levoglucosan. Furthermore, passive sampling was carried out at 11 sites in the Pearl River Delta of Southern China from January to April and July to September of 2015. Monosaccharide concentrations derived from PUF-PASs were comparable with the reported data obtained by active sampling, demonstrating that the PUF-PAS approach is valid for monosaccharides monitoring. On the basis of our approach, we found that there is a clear correlation between the monosaccharide concentrations and the MODIS fire activities during January-April.

Air samples were collected using polyurethane foam passive samplers from 26 air-monitoring stations located in the Pearl River Delta, China and two in Shaoguan City in Guangdong Province in 2015 to investigate the occurrence and distribution of priority polycyclic aromatic hydrocarbons (PAHs). Sixteen PAHs were identified and 15 of them (except for naphthalene) were quantified at a total concentration (∑15PAHs) that varied from 3.56 ng/m3 to 37.2 ng/m3 (average value 19.8 ± 9.69 ng/m3). The results indicated that PAHs with 3–4 benzene rings accounted for approximately 80% of all PAH compounds, among which phenanthrene and fluoranthene were the predominant components. Diagnostic parameters suggested that the possible sources of PAHs in the Delta region were mixed of petrogenic and pyrogenic sources from fuel/biomass/coal combustion. Based on the measured PAHs concentrations, the Carcinogenic Potency Risk (BaPeq) and Inhalation Cancer Risk (ICR) were assessed, and indicated that two air samples from Guangzhou and one from Foshan exceeded the BaPeq limit (1 ng/m3), whereas all samples from the 28 sampling locations exceeded the health-based guideline concentration for ICR. The results of this research suggest that a potential human health risk exists from PAHs in the study area via the respiration and inhalation pathway.

Silver nanoparticles (AgNPs) have attracted great attention in cancer theranostics due to their extraordinary physiochemical and biological properties. This review discusses a large number of papers and summarizes the recent applications of AgNPs in cancer theranostics from the following five perspectives: (1) desirable features of AgNPs for theranostic applications, (2) synthesis of AgNPs by physical, chemical, and biological processes, (3) applications of AgNPs in cancer theranostics in vitro, (4) applications of AgNPs in cancer theranostics in vivo, and (5) nanotoxicity of AgNPs. Furthermore, some views are discussed that concern the synthetic challenges, toxicity, and clinical translation of AgNPs and the future development of multifunctional theranostic platforms. Overall, the historical developments and recent applications of AgNPs confirm their important role in the cancer field. It is strongly believed that AgNPs will open a new route toward cancer theranostics in the near future.

Metallo-β-lactamases (MBLs) are a family of Zn(II)-dependent enzymes that can hydrolyze almost all β-lactam antibiotics. Horizontal transfer of the genes encoding MBLs among Gram-negative bacteria pathogens has led to the emergence of extensively drug-resistant pathogens, which now represent a major threat to human health. As there is not to date yet a clinically available MBL inhibitor, the discovery of new MBL inhibitors has great urgency. This review highlights the recent developments in the discovery of small-molecule MBL inhibitors.

Despite the great achievements of nanomedicines made in cancer chemotherapy, precise tumor targeting and deep penetration are still major challenges. Many nanomedicines can only passively accumulate near leaky site of tumor vessels through the enhanced permeability and retention (EPR) effect and cannot reach the deep region of tumor. To improve the tumor targeting, penetration and retention efficiency, an iRGD-mediated and enzyme-induced precise targeting gold nanoparticles system (iRGD/AuNPs-A&C) was developed by simply coadministering a tumor-homing penetration peptide iRGD (CRGDKGPDC) with a legumain responsive aggregable gold nanoparticle (AuNPs-A&C). In vitro, iRGD/AuNPs-A&C showed a consistent increase rate in size with AuNPs-A&C, suggesting that iRGD/AuNPs-A&C could also aggregate in the presence of legumain, which was in favor of the enhanced retention in tumor microenvironment. Meanwhile, iRGD/AuNPs-A&C showed higher 4T1 cells cellular uptake in vitro and presented higher penetration and accumulation in breast tumor in vivo than AuNPs-A&C, leading to enhanced tumor imaging efficacy and the improved chemotherapeutic effect to 4T1-bearing mice. These results suggested that the iRGD-mediated and enzyme-induced dual-functional nanoplatform was promising for the 4T1 tumor imaging and treatment.

The process of the production of multi-crystalline silicon is also that of incessant purification of metallurgical grade silicon, during which high energy consumption and environmental pollutants are inevitable. The paper, which is based on life cycle assessment (LCA), presents calculation and analysis on resource input, energy consumption, emissions into and comprehensive impact on environment generated from the whole process in which 1 kg of solar grade multi-crystalline silicon (SoG-Si) is produced with metallurgical route. The program is based on its research on four representative processes in metallurgical route, namely slag refining, wet purification, directional solidification and electron beam melting. Key factors determining environmental load are sought out through contribution analysis and improvement evaluation. Measures and suggestions on how to improve are proposed. For the first time, the LCA model of comparison of metallurgical route and modified Siemens process to SoG-Si environmental impact is constructed. The environmental impacts of SoG-Si production via metallurgical route is compared with purification via modified Siemens process. Results show that the comprehensive environmental impact of metallurgical route SoG-Si is only 49.57% of modified Siemens process SoG-Si. The metallurgical route enjoys obvious environmental advantage. The improvement should be focused on the reduction of electric power consumption in production processes.

In this study, we developed a highly compact microgripper with an only 300- μ m thick jaw and yet an amplification ratio of more than 20. A total of 18 flexure hinges were employed to achieve a low impedance grasping mechanism and diminish backlash. To achieve precise manipulation, a strain-gage-based position sensor was embedded within the microgripper to investigate the jaw displacement. Conventionally, the position sensors were calibrated by additional equipment, such as laser sensor to adjust the jaw motion stroke for the manipulation of multisized objects, which was a sophisticated process. To avoid such process, we proposed a simple visual-based online calibration method. As a result, the effectiveness and feasibility of the proposed method were verified successfully in picking and placing microspheres and microobjects with the scale ranging from hundreds of microns to a few.

A 64-channel massive multiple-input multiple-output (MIMO) transceiver with a fully digital beamforming (DBF) architecture for fifth-generation millimeter-wave communications is presented in this paper. The DBF-based massive MIMO transceiver is operated at 28-GHz band with a 500-MHz signal bandwidth and the time division duplex mode. The antenna elements are arranged as a 2-D array, which has 16 columns (horizontal direction) and 4 rows (vertical direction) for a better beamforming resolution in the horizontal plane. To achieve half-wavelength element spacing in the horizontal direction, a new sectorial transceiver array design with a bent substrate-integrated waveguide is proposed. The measured results show that an excellent RF performance is achieved. The system performance is tested with the over-the-air technique to verify the feasibility of the proposed DBF-based massive MIMO transceiver for high data rate millimeter-wave communications. Using the beam-tracking technique and two streams of QAM-64 signals, the proposed millimeter-wave MIMO transceiver can achieve a steady 5.3-Gb/s throughput for a single user in fast mobile environments. In the multiple-user MIMO scenario, by delivering 20 noncoherent data streams to eight four-channel user terminals, it achieves a downlink peak data rate of 50.73 Gb/s with the spectral efficiency of 101.5 b/s/Hz.

Water soluble organic carbon (WSOC) can significantly influence the aerosol optical properties and the aqueous phase chemistry in cloudwater, fogwater and aerosol liquid water. Here, we examine how the changing pH (in acidic range) affects the absorption spectra of aqueous extracts from field biomass burning aerosols, under dark conditions and in presence of simulated sunlight illumination. The observation under dark conditions indicates that pH variation from 2 to 5 induces significantly enhanced light absorbance in the wavelength ranges of 235–270 nm and 300–550 nm, whereas the light absorbance decreased in the range of 270–300 nm, which might be partially ascribed to the deprotonation of carboxylic acids and phenols. During the extract photolysis, light absorption exhibits photo-bleaching below 380 nm and photo-enhancement above 380 nm, indicating that at acidic levels (pH = 2–5), the particle extracts could undergo a significant composition evolution leading to a modification of absorptive properties. Meanwhile, after 12 h-photolysis, the acidity ([H+]) normalized by WSOC concentration in aqueous extracts ([WSOCae]) increased with a variation of Δ[H+]/[WSOCae]=(3.7 ± 0.7) × 10−7 mol mgC−1 (mean ± standard deviation), suggesting the formation of new acidic substances. Although these findings were acquired in aqueous solutions more relevant to cloud and fog water, the similar evolution likely occurs in wetted aerosols. This calls more attention to the effect of acidity on the wetted aerosols in order to better estimate the aerosol radiative forcing.

Various factors have been reported to be associated with early miscarriages, including microbial infection, chemical toxicity, maternal disorders and genetic abnormalities. In the present study, a prospective cohort study was conducted to investigate whether urinary concentrations of hydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) were associated with early pregnancy loss in women undergoing in vitro fertilization-embryo transfer (IVF-ET). Risk of spontaneous pregnancy loss in patients exposed to PAHs was analysed using 40 patients who had experienced early pregnancy loss compared to 40 who had normal live births. Single spot morning urine samples were collected from each patient 30 days after embryo transfer when clinical pregnancy was confirmed and ten urinary OH-PAHs were measured. After adjustment for age and BMI using a Log Binomial Model, only 2 + 3-PHE was found to be associated positively with early miscarriage. Using Receiver Operating Characteristic (ROC) curve analysis, the Area Under the Curve (AUC) was 0.78 (p＜0.001), suggesting that 2 + 3-PHE might provide a potential biomarker to predict the miscarriage risk in patients exposed to high level of PAHs.

The thermal conductive behavior of Zirconium diboride (ZrB 2 ) coated with different proportions nanoalumina (Al 2 O 3 ) in epoxy composites was investigated by the laser flash experimental and finite element analysis (FEA) methods. The coated ZrB 2 composite particles were categorized into the 3-1, 3-2, 3-3 and 3-4 systems, which corresponded to four different mass ratios of ZrB 2 particles to Al 2 O 3 particles, respectively. It could be found that the coated ZrB 2 composite particles were effective for increasing the thermal conductivity of the filled epoxy composites due to more effective formation of the conductive chain structure in the composites compared to the single-phase particles. In comparison, the system of 3-3 showed the most positive effect on improving the thermal conductive performance of epoxy composites. For composites with a 7 vol% of ZrB 2 /Al 2 O 3 composite particles of 3-3 system, its thermal conductivity was 0.65 W m −1 K −1 , increased by 20% and 79% relative to single-filled composites of ZrB 2 and Al 2 O 3 with same filled content, respectively. The predicted thermal conductive results of Al 2 O 3 coated ZrB 2 particles in epoxy matrix obtained by finite element analysis were in reasonable agreement with the experimental results.

In twin-screw refrigeration compressor for high pressure applications, journal bearing has been a preferred option to bear larger and larger radial force. Hence, the stability of rotor-journal bearing system is worth investigating to ensure the reliability of a twin-screw refrigeration compressor, which can be reflected on axis orbit. This paper presents a homogeneous two-phase flow model to calculate the axis orbit of journal bearing used in a twin-screw compressor, considering gas-induced force, unbalanced force and gravitational force. In order to compute gas-induced force acting on bearings by FEM, the p-V indicator diagram is measured experimentally. In addition, axial orbit under different evaporating temperature and different built-in volume ratio was investigated experimentally. Meanwhile it verifies that the proposed two-phase flow model has a good agreement in terms of orbit shape with the experimental result. Moreover, the effects of refrigerant mass fraction at supply groove and structural parameters are analyzed theoretically.

The Dabeigou Formation in the Luanping basin in northern China is well known for its continuous non-marine Lower Cretaceous deposits and the preservation of the early Jehol Biota, including abundant ostracods. However, the age of the Dabeigou Formation is still disputed. Here, we present a detailed lithostratigraphic analysis and ostracod biostratigraphy of the newly exposed Yushuxia section of the Luanping basin. At this locality, the Dabeigou Formation can be subdivided into 46 layers, which is mainly composed of grey to dark grey fine clastics of semi-deep lake face. Ostracod analysis on samples from the Dabeigou Formation revealed 14 species of nine genera. Biostratigraphically, the ostracods of the Dabeigou Formation belong to the Luanpingella-Torinina-Eoparacypris Zone. Most of the species range from the latest Jurassic to the earliest Cretaceous. However, some species show a closer relation with ostracods from the upper Lower Cretaceous Dadianzi Formation (upper Hauterivian to Barremian), the Yixian Formation (lower Aptian) of North China, and the Purbeck–Wealden Group (uppermost Tithonian to lowermost Aptian) of Britain. Combined with the biostratigraphy of other fossils and the U-Pb age, it is suggested that the ostracod fauna of the Dabeigou Formation and the origin of early Jehol Biota might be of Early Cretaceous age entirely.

Effective long-term monitoring of tumor growth is significant for the evaluation of cancer therapy. Aggregation-induced emission-active near-infrared (NIR) fluorescent organic nanoparticles (TPFE-Rho dots) are designed and synthesized for long-term in vitro cell tracking and in vivo monitoring of tumor growth. TPFE-Rho dots display the advantages of NIR fluorescent emission, large Stokes shift (∼180 nm), good biocompatibility, and high photostability. In vitro cell tracing studies demonstrate that TPFE-Rho dots can track SK-Hep-1 cells over 11 generations. In vivo optical imaging results confirm that TPFE-Rho dots can monitor tumor growth for more than 19 days in a real-time manner. This work indicates that TPFE-Rho dots could act as NIR fluorescent nanoprobes for real-time long-term in situ in vivo monitoring of tumor growth.

On-line gas chromatography–pyrolysis coupled to gas chromatography–isotope ratio mass spectrometry was used here for the position-specific isotope analysis (PSIA) of propane. First, based on the conversion rate of propane and its products, 800–840 °C was considered optimal for propane pyrolysis. The major pyrolytic fragments of propane included CH4, C2H4, C3H6, and C2H6. Subsequent isotope labeling experiments showed that CH4 and C2H6 were derived entirely from the terminal carbons, whereas C2H4 and C3H6 were derived from both terminal and central positions of propane. Therefore, the 13C enrichment factor associated with the major reactions during the pyrolysis process and position-specific δ13C values of propane can be estimated from the amount and δ13C values of the pyrolytic fragments using isotope mass balance. The obtained enrichment factors depended on the pyrolysis temperature, which can be used to calculate position-specific δ13C values for propane measured with this system. The results suggest that a relatively accurate site-preference value for propane can be obtained by this method. Therefore, the combination of compound-specific isotope analysis and PSIA of propane will be a powerful tool to discriminate the different origins of gases.

Exposure to metal(loid)s can lead to adverse effects on nervous system in children. However, little is known about the possible interaction effects of simultaneous exposure to multiple metal(loid)s on children's intelligence. In addition, relationship between blood lead concentrations (100 μg/L) and the intelligence of children over 5 years needs further epidemiological evidence. We recruited 530 children aged 9-11 years, including 266 living in a town near an industrialized area and 264 from another town in the same city in South China as a reference. The levels of lead (Pb), cadmium (Cd), arsenic (As) and mercury (Hg) in blood (BPb, BCd, BAs, BHg) and urine (UPb, UCd, UAs, UHg) were assessed, as well as children's intelligence quotient (IQ). A significant decrease in IQ scores was identified in children from the industrialized town (p .05), who had statistically higher geometric mean concentrations of BPb, BCd, UPb, UCd and UHg (65.89, 1.93, 4.04, 1.43 and 0.37 μg/L, respectively) compared with children from the reference town (37.21, 1.07, 2.14, 1.02 and 0.30 μg/L, respectively, p .05). After adjusting confounders, only BPb had a significant negative association with IQ (B = -0.10, 95% confidence interval: -0.15 to -0.05, p .001), which indicated that IQ decreased 0.10 points when BPb increased 1 μg/L. Significant negative interactions between BAs and BHg, positive interaction between UPb and UCd on IQ were observed (p .10), and BPb100 μg/L still negatively affected IQ (p .05). Our findings suggest that although only BPb causes a decline in children's IQ when simultaneously exposed to these four metal(loid)s at relatively low levels, interactions between metal(loid)s on children's IQ should be paid special attention, and the reference standard in China of 100 μg/L BPb for children above 5 years old should be revised.

Two kinds of noise-like pulse bunches are observed in an erbium-doped fiber ring laser for the first time. Picosecond- and submicrosecond-scale pulse bunches with energy of 0.32 nJ and 7.1 nJ, respectively, are generated and used in super-continuum generation. Using a 50-m dispersion-shifted fiber (DSF) a 20-dB bandwidth of over 750 nm is obtained.

Adipose-derived stem cells (ADSCs) have recently been considered as a promising therapy for erectile dysfunction (ED). However, the mechanism of ADSC-based therapy is unclear. Insulin-like growth factor-1 (IGF-1), basic fibroblast growth factor (bFGF), and vascular endothelial growth factor (VEGF) secreted by ADSCs were assessed in vitro. Sixteen 24-month-old male Sprague-Dawley rats were used for comparative analysis of 2-week treatment with labeled ADSCs or PBS. Eight additional 5-month-old rats were used as a young rat group. At 2 weeks post-transplantation, all rats were analyzed for erectile function, cavernous IGF-1, bFGF and VEGF levels, and penile histology. Conditioned medium and co-culture systems were used in cell experiments to detect how growth factors act on corpus cavernosum smooth muscle cells (CCSMCs) under oxidative stress conditions via crystal violet staining and immunofluorescence staining. We found that ADSCs secreted significantly higher IGF-1, bFGF, and VEGF levels in culture medium compared with basal medium. Compared with young rats, untreated aged rats had significantly lower Max ICP/MAP and ADSC treatment significantly increased the ratio. Immunofluorescence staining demonstrated a small number of labeled ADSCs in the corpus cavernosum. The untreated aged rats showed significantly decreased cavernous IGF-1, bFGF, and VEGF levels and significantly decreased contents of cavernous smooth muscle and endothelium compared with young rats. ADSC treatment partially normalized these alterations. In cell experiments, the groups receiving growth factor neutralizing antibody separately or combined had significantly decreased numbers of CCSMCs compared with control groups. These results indicated that ADSC treatment may improve aging-related ED partially through the secretion of IGF-1, bFGF, and VEGF.

A low-profile circularly polarised (CP) antenna with conical-beam radiation pattern is presented. The proposed antenna consists of a monopolar patch antenna fed by a probe in the centre and a ring-shaped array formed by eight modified parasitic patch elements. Two resonant modes of the monopolar patch which connects to a ground plane by a set of conductive shorting vias are utilised to achieve wide impedance bandwidth. A CP conical-beam radiation pattern is formed by loading the designed array. Loop current and slot resonant mode are employed to discuss the operating principle. A parametric study is carried out for the detailed design concept illustration. To verify the design, a prototype has been fabricated and measured, which shows a low profile of 0.059 λ 0 , a maximum gain of 7.45 dBic, a 10-dB impedance bandwidth of 23.1%, a 3-dB axial ratio bandwidth of 9.6% and a good conical-beam radiation pattern.

Blood vessel development is critical for the continued growth and progression of solid tumors and, therefore, makes an attractive target for improving cancer therapy. Indeed, vascular-targeted therapies have been extensively explored but they have shown minimal efficacy as monotherapies. Combretastatin A4 (CA-4) is a tubulin-binding vascular disrupting agent that selectively targets the established tumor endothelium, causing rapid vascular beak down. Despite its potent anticancer potential, the drug has dose-limiting side effects, particularly in the form of cardiovascular toxicity. Furthermore, its poor aqueous solubility and the resulting limited bioavailability hinder its antitumor activity in the clinic. To improve the therapeutic efficacy of CA-4, we investigated its application as a combination therapy with doxorubicin (Dox) in a tumor vasculature targeted delivery vehicle: peptide-modified cross-linked multilamellar liposomal vesicles (cMLVs). In vitro cell culture studies showed that a tumor vasculature-targeting peptide, RIF7, could facilitate higher cellular uptake of drug-loaded cMLVs, and consequently enhance the antitumor efficacy in both drug resistant B16 mouse melanoma and human MDA-MB-231 breast cancer cells. In vivo, upon intravenous injection, targeted cMLVs could efficiently deliver both Dox and CA-4 to significantly slow tumor growth through the specific interaction of the targeting peptide with its receptor on the surface of tumor vasculature. This study demonstrates the potential of our novel targeted combination therapy delivery vehicle to improve the outcome of cancer treatment.

Exposure to polycyclic aromatic hydrocarbons (PAHs) could cause high blood pressure (BP) and increased risk for atherosclerotic cardiovascular disease (ASCVD). However, the mechanisms underlying the relationship between them were unclear. We investigated potential mediation effect of obesity on the association of exposure to PAHs with high BP and increased risk for ASCVD. In the repeated measures study, 106 community-dwelling residents in Wuhan, China finished the physical examination in the winter and summer seasons, eight urinary PAHs metabolites were measured. Associations of urinary PAHs with high BP and increased risk for ASCVD were assessed using either linear mixed effect models or generalized estimating equations models. Mediation analysis was performed to evaluate the mediating effect of obesity on the association of urinary PAHs metabolites with high BP or increased risk of ASCVD. We observed the positive association between urinary PAHs metabolites and BP or the odds ratios for high BP (all P

A low-profile substrate-integrated waveguide (SIW) cavity-based antenna with conical-beam circularly polarized (CP) radiation is presented. Conical-beam CP radiation is obtained by the combination of a radial current source and a loop current source, which are produced by a shorted monopole patch and an annular array, respectively. The proposed annular array configuration is designed by combining multiple identical customized parasitic patch elements arranged around the monopole. Phase compensatory lines and shorted annular ring slots are introduced in the array to tune phase difference of two current sources and to generate in-phase currents on the elements, respectively. All antenna elements are simultaneously excited within a center-fed SIW cavity. In order to fully picture the operating mechanism, we analyze the wide impedance and axial-ratio (AR) bandwidths based on an equivalent circuit model and an electromagnetic theory. Then, parametric studies are carried out for a detailed design illustration. To verify the design, a prototype has been fabricated and measured, which shows a stable conical-beam radiation and good performance including: a low profile of $0.062\lambda _{0}$ , a 10 dB impedance bandwidth of 20.4%, a 3 dB AR bandwidth of 17%, a maximum gain of 8.25 dBic, and an advantage of large ground compatibility.

The characteristics and applications of carbonaceous materials play a vital role in silicon production using an electric arc furnace, as this is an energy-intensive industry with high energy operating costs that is currently facing severe challenges to become more sustainable and more competitive. In this study, the effect of different carbon materials on specific electrical consumption and the exergetic efficiency and the silicon yield for two types of furnace was investigated using a statistical analysis method based on actual production data from the silicon plant. The highest exergetic efficiency values of 0.39 (8.3 MVA) and 0.42 (12.5 MVA) without recovery were obtained by the application of petcoke and charcoal. The exergetic efficiency was higher in the larger capacity furnace than in the smaller furnace for the same consumption of raw materials. The correlation between exergetic efficiency and carbon materials was evaluated and revealed that the moisture content and graphitization of raw materials have a significant effect on the exergetic efficiency. The reactivity of mixtures was improved by synergistic interactions between petcoke and coal or woodchips, which increased the carbothermic reduction utilization of silica based on the higher silicon yield indicator, but reduced the exergetic efficiency and silicon actual production, as it increased the specific electrical consumption.

The Pearl River and its tributaries receive discharges of treated/untreated domestic sewage and industrial wastewater throughout the entire drainage basin. The river provides source water for many local inhabitants, and there is great concern over its pollution status. Fifteen sediment samples were collected from source water areas in the Pearl River Delta (PRD), and analyzed for the occurrence and distribution of two classes of emerging pollutants, namely, organophosphorus flame retardants (OPs) and synthetic musks. In most sediments, five polycyclic musks and two nitromusks were detected, and galaxolide (HHCB) and tonalide (AHTN) were the predominant components, with concentrations of 0.030–547 and 4.31–439 ng/g, respectively. Seven widely-used OPs were found in most sediments; the total concentrations of OPs varied in the range of 1.79–143 ng/g, with tris(2-butoxyethyl) phosphate (TBEOP), tris(2-chloro-isopropyl) phosphate (TCIPP), and triphenyl phosphate (TPHP) being the main components. The results indicated that industrial discharge and domestic sewage played important roles for synthetic musks and OPs distribution in sediments in the study area. In general, higher levels of OPs and synthetic musks were found in Guangzhou, Foshan, and Dongguan, suggesting a significant impact from industrial discharges and the dense population of these regions. This article is protected by copyright. All rights reserved

Purpose The purpose of this paper is to study the effects of these major parameters, including layer thickness, deposition velocity and infill rate, on product’s mechanical properties and explore the quantitative relationship between these key parameters and tensile strength of the part. Design/methodology/approach A VHX-1000 super-high magnification lens zoom three-dimensional (3D) microscope is utilized to observe the bonding degree between filaments. A temperature sensor is embedded into the platform to collect the temperature of the specimen under different parameters and the bilinear elastic-softening cohesive zone model is used to analyze the maximum stress that the part can withstand under different interface bonding states. Findings The tensile strength is closely related to interface bonding state, which is determined by heat transition. The experimental results indicate that layer thickness plays the predominant role in affecting bonding strength, followed by deposition velocity and the effect of infill rate is the weakest. The numerical analysis results of the tensile strength predict models show a good coincidence with experimental data under the elastic and elastic-softened interface states, which demonstrates that the tensile strength model can predict the tensile strength exactly and also reveals the work mechanism of these parameters on tensile strength quantitatively. Originality/value The paper establishes the quantitative relationship between main parameters including layer thickness, infill rate and deposition velocity and tensile strength for the first time. The numerically analyzed results of the tensile strength predict model show a good agreement with the experimental result, which demonstrates the effectiveness of this predict model. It also reveals the work mechanism of the parameters on tensile strength quantitatively for the first time.

Heteroatom-doped carbon dots (CDs) with excellent optical characteristics and negligible toxicity have emerged in many applications including bioimaging, biosensing, photocatalysis, and photothermal therapy. The metal-doping of CDs using various heteroatoms results in an enhancement of the photophysics but also imparts them with multifunctionality. However, unlike nonmetal doping, typical metal doping results in low fluorescence quantum yields (QYs), and an unclear photoluminescence mechanism. In this contribution, we detail results concerning zinc doped CDs (Zn-CDs) with QYs of up to 35%. The zinc ion charges serve as a surface passivating agent and prevent the aggregation of graphene π–π stacking, leading to an increase in the QY of the Zn-CDs. Structural and chemical investigations using spectroscopic and first principle simulations further revealed the effects of zinc doping on the CDs. The robust Zn-CDs were used for the ultra-trace detection of Hg2+ with a detection limit of 0.1 μM, and a quench mechanism was proposed. The unique optical properties of the Zn-CDs have promise for use in applications such as in vivo sensing and future phototherapy applications.

Due to the extensive application of synthetic organic chemicals, the resulting environmental contamination with such chemicals is of great concern. Herein, we describe the development of a simple analytical method to determine several groups of organic compounds in sediment samples. Samples were soxhlet-extracted with dichloromethane, separated, and cleaned-up by passage through a combined column of neutral alumina/silica gel, then identified and determined by GCMS analysis. Four sediment samples were analyzed to validate the efficiency, and acceptable recoveries and good repeatability were obtained. • Combined chromatographic columns of silica gel and alumina have been used for separation and clean-up. • Five groups of organic compounds have been simultaneously analyzed. • Acceptable recoveries with good reproducibility have been achieved. Method name: Multiple-residue analytical method, Keywords: Synthetic musks, PAHs, Organophosphate esters, UV filters, Analytical method