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Ferroptosis holds significant potential for application in cancer therapy. However, ferroptosis inducers are not cell-specific and can cause phospholipid peroxidation in both tumor and non-tumor cells. This limitation greatly restricts the use of ferroptosis therapy as a safe and effective anticancer strategy. Our previous study demonstrated that macrophages can engulf ferroptotic cells through Toll-like receptor 2 (TLR2). Despite this advancement, the precise mechanism by which phospholipid peroxidation in macrophages affects their phagocytotic capability during treatment of tumors with ferroptotic agents is still unknown. Here, we utilized flow sorting combined with redox phospholipidomics to determine that phospholipid peroxidation in tumor microenvironment (TME) macrophages impaired the macrophages ability to eliminate ferroptotic tumor cells by phagocytosis, ultimately fostering tumor resistance to ferroptosis therapy. Mechanistically, the accumulation of phospholipid peroxidation in the macrophage endoplasmic reticulum (ER) repressed TLR2 trafficking to the plasma membrane and caused its retention in the ER by disrupting the interaction between TLR2 and its chaperone CNPY3. Subsequently, this ER-retained TLR2 recruited E3 ligase MARCH6 and initiated the proteasome-dependent degradation. Using redox phospholipidomics, we identified 1-steaoryl-2-15-HpETE-sn-glycero-3-phosphatidylethanolamine (SAPE-OOH) as the crucial mediator of these effects. Conclusively, our discovery elucidates a novel molecular mechanism underlying macrophage phospholipid peroxidation-induced tumor resistance to ferroptosis therapy and highlights the TLR2-MARCH6 axis as a potential therapeutic target for cancer therapy.

Stem cell-based transplantation is a promising therapeutic approach for intervertebral disc degeneration (IDD). Current limitations of stem cells include with their insufficient cell source, poor proliferation capacity, low nucleus pulposus (NP)-specific differentiation potential, and inability to avoid pyroptosis caused by the acidic IDD microenvironment after transplantation. To address these challenges, embryo-derived long-term expandable nucleus pulposus progenitor cells (NPPCs) and esterase-responsive ibuprofen nano-micelles (PEG-PIB) were prepared for synergistic transplantation. In this study, we propose a biomaterial pre-modification cell strategy; the PEG-PIB were endocytosed to pre-modify the NPPCs with adaptability in harsh IDD microenvironment through inhibiting pyroptosis. The results indicated that the PEG-PIB pre-modified NPPCs exhibited inhibition of pyroptosis in vitro; their further synergistic transplantation yielded effective functional recovery, histological regeneration, and inhibition of pyroptosis during IDD regeneration. Herein, we offer a novel biomaterial pre-modification cell strategy for synergistic transplantation with promising therapeutic effects in IDD regeneration.

Deep-sowing is an important method for avoiding drought stress in crop species, including maize. Identifying candidate genes is the groundwork for investigating the molecular mechanism underlying maize deep-sowing tolerance. This study evaluated four traits (mesocotyl length at 10 and 20 cm planting depths and seedling emergence rate on days 6 and 12) related to deep-sowing tolerance using a large maize population containing 386 inbred lines genotyped with 0.5 million high-quality single nucleotide polymorphisms (SNPs). The genome-wide association study detected that 273 SNPs were in linkage disequilibrium (LD) with the genetic basis of maize deep-sowing tolerance. The RNA-sequencing analysis identified 1 944 and 2 098 differentially expressed genes (DEGs) in two comparisons, which shared 281 DEGs. By comparing the genomic locations of the 273 SNPs with those of the 281 DEGs, we identified seven candidate genes, of which GRMZM2G119769encoded a sucrose non-fermenting 1 kinase interactor-like protein. GRMZM2G119769was selected as the candidate gene because its homologs in other plants were related to organ length, auxin, or light response. Candidate gene association mapping revealed that natural variations in GRMZM2G119769were related to phenotypic variations in maize mesocotyl length. Gene expression of GRMZM2G119769was higher in deep-sowing tolerant inbred lines. These results suggest that GRMZM2G119769is the most likely candidate gene. This study provides information on the deep-sowing tolerance of maize germplasms and identifies candidate genes, which would be useful for further research on maize deep-sowing tolerance.

ABSTRACTIntroductionBerberine (BBR), as one of the outstanding representatives of isoquinoline alkaloids, has been used as an antibacterial drug for a long time in China since ancient times. Currently, a large number of studies have been reported that berberine has a wide spectrum of pharmacological activities, such as anti-tumor, anti-inflammatory, hypoglycemic, hypolipidemic, anti-obesity, and the like.Areas coveredThis review systematically discussed important patents on berberine and berberine derivatives in terms of pharmacological activity between 2016 and 2020. These patents were mainly searched through the European Patent Office database and Web of Science. These berberine patents (~41) cover a wide range of applications, mainly including antitumor, anti-inflammatory, antibacterial, anti-metabolic disorder, and other newly reported pharmacological activities.Expert opinionBerberine is an important lead compound with great potential for optimization in drug development. However, there is a lack of research related to the biomolecular targets of BBR, which directly restricts the development of berberine in the pharmaceutical field. The problems involved with poor bioavailability and cytotoxicity are also worth considering in the development of berberine-based drugs. Accordingly, the increasing number of patents involving biomolecular targets in BBR’s patent applications will be published as its related pharmacological mechanisms are further deciphered.

The evaporation of a nano-suspension droplet on a substrate has gained extensive attention recently due to its potential application in the rising industry of functional coating. In this paper, we reported that the droplet evaporation behavior can be controlled by the nanoparticles’ concentration and the functional group on the surface of nanoparticles. Experimental results indicated that the suspension of nanoparticles notably enhanced the evaporation rate of droplets and decreased the duration time of the continuous-contact-radius (CCR) stage. This effect was more obvious when the nanoparticles were modified by the perfluorodecyltrimethoxysilane (PDTS), which made the particles more hydrophobic. Besides, the modified nanoparticles can effectively inhibit the formation of coffee rings during evaporation. These results may have important applications for the energy-efficient enhancement of the water evaporation rate.

Despite significant progress in the fabrication of prevascularized networks over the past decade, a number of challenges remain. One of the most relevant issues is the lack of three-dimensional (3D) structures, which limits the clinical applications of the engineered scaffolds. Another problem is the complexity of prevascularized networks in engineered scaffolds, which is still less than that of human tissues, especially in the case of mature and bulk tissues. Thus, there is still the need to develop more flexible methods to better simulate the structure of natural tissues. In this work, we used a versatile sacrificial template method to fabricate bulk scaffolds with spatial prevascularized networks. Soft poly(vinyl alcohol) (PVA) filaments were used to print the sacrificial template, and the receiving platform was a stepped shaft, allowing the sacrificial template to have a complex 3D structure. The obtained template was embedded into gelatin and microbial transglutaminase (mTG). The inner PVA template could be extracted from the enzymatic cross-linking system, and an engineered scaffold with spatial prevascularized networks was obtained. In vitro experiments demonstrated that the fabrication process is biocompatible with cells.

Two series of new double pyrazole Schiff base derivatives 4a–4tand 5a–5pas anti-TMV agents were designed and synthesized, in which compound 4jshowed the most potent anti-TMV activity. Molecular docking revealed 5-chloro-3-methyl-1H-pyrazole as scaffold of compound 4jcould insert into the nucleotide sequence (GAAGUU) of Ori-RNA target pocket stably.

Photocatalytic technology is widely used in water purification because of its environmental protection, high efficiency and energy saving. Therefore, it is extremely important for the selection and preparation of specific semiconductor materials used in the field of photocatalysis. In this work, 1T@2H MoS2 nanosheets were fabricated by simple hydrothermal method, and the photocatalytic property of as-prepared 1T@2H MoS2 were investigated by the photo-degradation of methylene blue (MB) water solutions under visible light irradiation via 2H MoS2.The results indicated that compared to 2H MoS2, the 1T@2H MoS2 exhibited more excellent photocatalytic degradation property. After 150 minutes of irradiation under visible light, 1T@2H MoS2 had a removal rate of 98% for MB, and 2H MoS2 eventually reached 19%. The enhancement photocatalytic property of 1T@2H MoS2 could be attributed to the reduced band gap energy of the hybrid-nanosheets and the increased in electron migration speed.

TP53 mutations frequently occur in head and neck squamous cell carcinoma (HNSCC) patients without human papillomavirus infection. The recurrence rate for these patients is distinctly high. It has been actively explored to identify agents that target TP53 mutations and restore wild-type (WT) TP53 activities in HNSCC. PRIMA-1 (p53-reactivation and induction of massive apoptosis-1) and its methylated analogue PRIMA-1Met(also called APR-246) were found to be able to reestablish the DNA-binding activity of p53 mutants and reinstate the functions of WT p53. Herein we report that piperlongumine (PL), an alkaloid isolated from Piper longumL., synergizes with APR-246 to selectively induce apoptosis and autophagic cell death in HNSCC cells, whereas primary and immortalized mouse embryonic fibroblasts and spontaneously immortalized non-tumorigenic human skin keratinocytes (HaCat) are spared from the damage by the co-treatment. Interestingly, PL-sensitized HNSCC cells to APR-246 are TP53 mutation-independent. Instead, we demonstrated that glutathione S-transferase pi 1 (GSTP1), a GST family member that catalyzes the conjugation of GSH with electrophilic compounds to fulfill its detoxification function, is highly expressed in HNSCC tissues. Administration of PL and APR-246 significantly suppresses GSTP1 activity, resulting in the accumulation of ROS, depletion of GSH, elevation of GSSG, and DNA damage. Ectopic expression of GSTP1 or pre-treatment with antioxidant N-acetyl-l-cysteine (NAC) abrogates the ROS elevation and decreases DNA damage, apoptosis, and autophagic cell death prompted by PL/APR-246. In addition, administration of PL and APR-246 impedes UMSCC10A xenograft tumor growth in SCID mice. Taken together, our data suggest that HNSCC cells are selectively sensitive to the combination of PL and APR-246 due to a remarkably synergistic effect of the co-treatment in the induction of ROS by suppression of GSTP1.

A novel efficient track initiation method is proposed for the harsh underwater target tracking environment (heavy clutter and large measurement errors): track splitting, evaluating, pruning and merging method (TSEPM). Track initiation demands that the method should determine the existence and initial state of a target quickly and correctly. Heavy clutter and large measurement errors certainly pose additional difficulties and challenges, which deteriorate and complicate the track initiation in the harsh underwater target tracking environment. There are three primary shortcomings for the current track initiation methods to initialize a target: (a) they cannot eliminate the turbulences of clutter effectively; (b) there may be a high false alarm probability and low detection probability of a track; (c) they cannot estimate the initial state for a new confirmed track correctly. Based on the multiple hypotheses tracking principle and modified logic-based track initiation method, in order to increase the detection probability of a track, track splitting creates a large number of tracks which include the true track originated from the target. And in order to decrease the false alarm probability, based on the evaluation mechanism, track pruning and track merging are proposed to reduce the false tracks. TSEPM method can deal with the track initiation problems derived from heavy clutter and large measurement errors, determine the target’s existence and estimate its initial state with the least squares method. What's more, our method is fully automatic and does not require any kind manual input for initializing and tuning any parameter. Simulation results indicate that our new method improves significantly the performance of the track initiation in the harsh underwater target tracking environment.

In the past, long-distance free-space quantum communication experiments could only be implemented at night. During the daytime, the bright background sunlight prohibits quantum communication in transmission under conditions of high channel loss over long distances. Here, by choosing a working wavelength of 1,550 nm and developing free-space single-mode fibre-coupling technology and ultralow-noise upconversion single-photon detectors, we have overcome the noise due to sunlight and demonstrate free-space quantum key distribution over 53 km during the day. The total channel loss is ∼48 dB, which is greater than the 40 dB channel loss between the satellite and ground and between low-Earth-orbit satellites. Our system thus demonstrates the feasibility of satellite-based quantum communication in daylight. Moreover, given that our working wavelength is located in the optical telecom band, our system is naturally compatible with ground fibre networks and thus represents an essential step towards a satellite-constellation-based global quantum network.

Background: G9a is the primary enzyme for mono- and dimethylation at Lys 9 of histone H3 and forms predominantly the heteromeric complex as a G9a-GLP (G9a-like protein) that is a functional histone lysine methltransferase in vivo. Mounting evidence suggests that G9a catalyzes methylation of histone and nonhistone proteins, which plays a crucial role in diverse biological processes and human diseases. Methods: In this study, the current knowledge on biological functions of G9a and inhibitors were summarized. Results: we review the current knowledge on biological functions of G9a, with particular emphasis on regulating gene expression and cell processes, and involvement in human diseases. We outline a perspective on various classes of G9a inhibitors to date from both articles and patents with an emphasis on their discovery, activity and the current research status. Conclusion: We highlight the key knowledge on potential biological functions and various human diseases. We also reviewed the discovery and characterization of the reported G9a inhibitors. However, we also propose the challenges and future opportunities in study of G9a. This review could make a crucial contribution to the long journey to develop drug-like molecules targeting G9a.

ObjectiveThe purpose of this study is to investigate the effect of kaempferol (KAE), an effective constituent of Buddleja officinalis, on human corneal epithelial cells (HCECs) under a hyperosmolar environment. MethodsHCECs were cultured in DMEM/F12 medium and allocated into four groups: normal, model, vehicle, and KAE. Ki67 staining was used to detect HCEC proliferation; TdT-mediated dUTP Nick-End Labeling staining was used to detect HCEC apoptosis; quantified real-time PCR was used to investigate the mRNA relative expression levels of TNF-a, IL-6, and p38. and Western blot was used to reveal the protein expression levels of TNF-a, IL-6, and p38. ResultsCompared with those in the normal group, the proliferation ability of HCECs was significantly inhibited and the apoptosis rate of HCECs was notably increased in the model group; but KAE could effectively improve HCEC proliferation and reduce HCEC apoptosis. Compared with those in the normal group, the mRNA relative expressions and protein levels of TNF-a, IL-6, and p38 were significantly increased in the model group, which were effectively decreased after KAE intervention. ConclusionKAE could promote HCEC proliferation and reduce cell apoptosis, as well as inhibit the expression of inflammatory factors in a hypertonic-induced HCEC model via the p38MAPK pathway.

Conjugated polymers containing alternating donor/acceptor units have strong and sharp absorbance peaks in near-infrared (NIR) region, which could be suitable for photothermal therapy. However, these polymers as photothermal transducers are rarely reported because of their water insolubility, which limits their applications for cancer therapy. Herein, we report the donor–acceptor conjugated polymer PBIBDF-BT with alternating isoindigo derivative (BIBDF) and bithiophene (BT) units as a novel photothermal transducer, which exhibited strong near-infrared (NIR) absorbance due to its low band gap (1.52 eV). To stabilize the conjugated polymer physiological environments, we utilized an amphiphilic copolymer, poly(ethylene glycol)-block-poly(hexyl ethylene phosphate) (mPEG-b-PHEP), to stabilize PBIBDF-BT-based nanoparticles (PBIBDF-BT@NPPPE) through a single emulsion method. The obtained nanoparticles PBIBDF-BT@NPPPEshowed great stability in physiological environments and excellent photostability. Moreover, the PBIBDF-BT@NPPPEexhibited high photothermal conversion efficiency, reaching 46.7%, which is relatively high compared with those of commonly used materials for photothermal therapy. Accordingly, in vivo and in vitro experiments demonstrated that PBIBDF-BT@NPPPEexhibits efficient photothermal anticancer efficacy. More importantly, PBIBDF-BT@NPPPEcould simultaneously encapsulate other types of therapeutic agents though hydrophobic interactions with the PHEP core and achieve NIR-triggered intracellular drug release and a synergistic combination therapy of thermo-chemotherapy for the treatment of cancer.

Benzophenone-3 (BP-3), as an important organic UV filter, is widely used in the sunscreen, cosmetic, and personal care products. The chemical reaction mechanism and kinetics of BP-3 degradation initiated by hydroxyl (OH) radical was investigated in the atmosphere based on the density functional theory (DFT). The results showed that the OH radical is more easily added to the C3 position of the aromatic ring (pathway 3), while the H atom abstraction from the OH group on the aromatic ring (pathway 23) is an energetically favorable reaction pathway. At ambient temperature, 298 K, the overall rate constant for the primary reaction is about 1.50 × 10−10cm3mol−1s−1with the lifetime of 1.92 h. OH addition reactions play the key role in the OH-initiated reaction of BP-3. The study is helpful for better understanding of the removal, transformation, and fate of BP-3 in the atmosphere.

Benzophenone-3 (BP-3), as an important organic UV filter, is widely used in the sunscreen, cosmetic, and personal care products. The chemical reaction mechanism and kinetics of BP-3 degradation initiated by hydroxyl (OH) radical was investigated in the atmosphere based on the density functional theory (DFT). The results showed that the OH radical is more easily added to the C3 position of the aromatic ring (pathway 3), while the H atom abstraction from the OH group on the aromatic ring (pathway 23) is an energetically favorable reaction pathway. At ambient temperature, 298 K, the overall rate constant for the primary reaction is about 1.50 × 10−10cm3mol −1s−1with the lifetime of 1.92 h. OH addition reactions play the key role in the OH-initiated reaction of BP-3. The study is helpful for better understanding of the removal, transformation, and fate of BP-3 in the atmosphere.

Multidrug resistance (MDR) has been recognized as a key factor contributing to the failure of chemotherapy for cancer in the clinic, often due to insufficient delivery of anticancer drugs to target cells. For addressing this issue, a redox-responsive polyphosphoester-based micellar nanomedicine, which can be triggered to release transported drugs in tumor cells, has been developed. The micelles are composed of diblock copolymers with a hydrophilic PEG block and a hydrophobic polyphosphoester (PPE) block bearing a disulfide bond in a side group. After incubating the redox-responsive micelles with drug-resistant tumor cells, the intracellular accumulation and retention of DOX were significantly enhanced. Moreover, after internalization by MDR cancer cells, the disulfide bond in the side group was cleaved by the high intracellular glutathione levels, resulting in a hydrophobic to hydrophilic transition of the PPE block and subsequent disassembly of the micelles. Thus, the encapsulated DOX was rapidly released, and abrogation of drug resistance in the cancer cells was observed in vitro. Moreover, the DOX-loaded redox-responsive micelles exhibited significantly enhanced inhibition of tumor growth in nude mice bearing MCF-7/ADR xenograft tumors via tail vein injection, indicating that such micelles have great potential in overcoming MDR for cancer therapy.

In this Letter, a periodic structure in which each unit cell consists of one manganese oxide (La_0.7Ca_0.3MnO_3) strip and two gold strips is designed. By simulating the electromagnetic responses of the structure, we confirm that Fano resonances can be actively controlled in the infrared region by modulating the intensity of the external magnetic field applied to the structure. This is due to the colossal magneto-resistance of the La_0.7Ca_0.3MnO_3 material. Furthermore, a transmission phase can also be effectively tuned. The phase has a shift of ΔΦ=1.05  rad at a frequency of 130 THz when the intensity of the external magnetic field varies from 5083 to 5193  kA/m. Such a tunable method has potential applications in controllable photoelectric elements.

Hexagonal (β)-phase NaYF4:Yb3+, Er3+ upconversion nanoparticles (UCNPs) with and without an inert (undoped NaYF4) shell have been successfully synthesized and the effects of shell thickness on the upconversion luminescence (UCL) and temperature sensing properties were systematically investigated. It was found that the NaYF4 shell and its thickness do not affect the RHS values and thermal sensitivity, but can obviously improve the UCL intensity of NaYF4:Yb3+, Er3+ UCNPs. It implies that the core-shell structured NaYF4:Yb3+, Er3+@NaYF4 UCNPs with excellent UCL properties have great potential to be used as temperature sensing probes in biomedical fields, without considering the influences of the shell thickness on their temperature sensing properties.

Composite nanostructures of NaYF4:Yb3+, Er3+@Au have been successfully prepared by attaching gold nanoparticles onto the surface of NaYF4: Yb3+, Er3+ upconversion nanoparticles (UCNPs). NaYF4 inert shell was used to adjust the separation distance between gold nanoparticles and UCNPs. Effects of the gold nanoparticles on their upconversion luminescent (UCL), temperature sensing and photothermal therapy properties were systematically investigated. For all samples, a slight decrease of the UCL intensity was observed after gold nanoparticles attachment, suggesting that the nonradiative quenching effect is the dominant interaction between UCNPs and gold nanoparticles. However, the reduction of the UCL intensity is negligible due to the significant improvement of UCL properties by NaYF4 shell. In addition, the gold attachment can obviously improve the photothermal conversion effect, but do not affect the temperature sensing properties of NaYF4:Yb3+, Er3+ UCNPs, indicating their high capability for multifunctional applications in biomedical fields.

Recently, micelles, which are self-assembled by amphiphilic copolymers, have attracted tremendous attention as promising drug delivery systems for cancer treatment. Thus, the hydrophobic core of the micelles, which could efficiently encapsulate small molecular drug, will play a significant role for the anticancer efficiency. Unfortunately, the effect of hydrophobicity of micellar core on its anticancer efficiency was rarely reported. Herein, the amphiphilic diblock polymers of poly(ethylene glycol) and polyphosphoester with different side groups (butyl, hexyl, octyl) were synthesized to tune the hydrophobicity of the micellar core. We found that the in vitro cytotoxicity of the DOX-loaded micelles decreased with the increasing hydrophobicity of micellar core due to the drug release rate. However, following systemic delivery, the DOX-loaded micelles with the most hydrophobic core exhibited the most significant inhibition of tumor growth in a MDA-MB-231 tumor model, indicating the importance of hydrophobicity of core on the antitumor efficacy of drug delivery systems.

In this paper, voltage fluctuation and stability analysis of critical buses was performed using multiple indexes to power system with wind farm connected. Considering the intermittency and randomness of wind speed, this paper constructed three voltage fluctuation indexes according to the characteristic of voltage random distribution. Bus voltage stability index was also calculated with the help of PV and QV curves in the paper. The simulation analysis performed in the DIgSILENT/PowerFactory basing on three machines nine nodes system with double-fed wind farm was carried out to reveal the impacts of wind generation uncertainty on voltage fluctuation and stability.

Based on the model of rigid-spring element suitable for homogeneous elastic problem, which was developed by Japanese professor Kawai, the interface stress element model (ISEM) for solving the problem of discontinuous media mechanics has been established. Compared with the traditional finite element method (FEM), the ISEM is more accurate and applicable. But on the other hand, the total number of freedom degree of ISEM in dealing with three-dimensional problems is higher than that of FEM, which often brings about the negative effects on efficiency of calculation. Therefore, it is necessary to establish a mixed model by gathering the advantages of ISEM and FEM together. By making use of the good compatibility of ISEM and introducing the concept of transitional interface element, this paper combines the counting methods of ISEM and FEM, and proposes a mixed model of ISEM-FEM, which can solve, to a large extent, the contradictions between accuracy and efficiency of calculation. The examples prove the applicability and adaptability of this model to engineering.

A new fuzzy multiple reference model adaptive control method combined with fuzzy select and conventional adaptive control is presented. To overcome the control difficulties which due to significant and unpredictable system parameter variations, fuzzy logic rules are designed to choose the suitable reference model. The new method is applied to control the speed servo system of dynamic model of BLDCM, and the simulation results show it works well with high dynamic performance and control precision under the condition of great change in reference speed and load torque.

Against the background of the development of the smart grid, in order to promote the development of intelligent electricity in the residents side, developed a demand response based household electricity intelligent interactive terminal. The interactive terminal use configuration software as platform, combined with the existing peak-valley price and ladder price in Shanghai, consider of the real-time price mechanism and interruptible load mechanism of the demand response, cooperate with the intelligent socket which independently researched and developed, the intelligent interactive terminal is family oriented with information visualization, with a variety of control methods and easy to use. Through simulation and experiment, the terminal can achieve user-friendly, save energy, convenient supply company and user control, and improve the effect of users life habit.

The application of virtual simulation experiment platform has changed the traditional teaching method fundamentally, reduce the cost of laboratory construction and management, which has important reference value to realize the remote experiment teaching. Through this experiment, students' interest in knowledge is cultivated and innovation ability is enhanced. The virtual simulation experiment platform consists of hardware and software function modules, which are both designed in this thesis.There are five experiments available for choose as following: virtual oscillograph, spectrum analysis, formula-wave generator, temperature measurement with K-thermocouple, Fourier transform comparison.

Four europium trifluoroacetate complexes, Eu(CF3COO)3·bpy(bpy=2,2′-bipyridine)(1), Eu(CF3COO)3·phen(phen=1,10-phenanthroline)(2), Eu(CF3COO)3·2bp(bp=benzophenone)(3) and Eu(CF3COO)3·2tppo(tppo=triphenyl-phosphine oxide)(4) were synthesized and characterized by elemental analysis, Fourier transform infrared(FTIR) spectroscopy, photoluminescence(PL) spectroscopy and thermogravimetric analysis(TGA). The PL spectra of the complexes at room temperature show the strong typical Eu3+ion red emission, due to the efficient energy “antenna absorption” of ligands and transitions of Eu3+ion between 5D0→7FJ(J=0–4). The long lifetime and high quantum yield reflect that the multiphonon relaxations by coupling to O-H and C-H vibrations were reduced. According to the photoluminescent spectra, the Judd-Ofelt parameters Ω2and Ω4of the complexes were calculated and the radiative properties were also presented. The 5D0radiative lifetime, quantum yield and the stimulated emission cross-section of the complexes are excellent, which prove that they have promising optical properties for liquid laser. The thermal analyses indicate that they are quite stable to heat.

Wind energy conversion is the fastest-growing source of new electric generation in the world. The unforeseen damages of a component in a wind turbine have significant impact on the wind turbines, especially offshore ones. There has been a trend towards adoption of various forms of condition monitoring and fault diagnosis to know the deteriorating condition for both mechanical and electrial components, well in advance of a breakdown. This paper review the most recent advances in these areas with a special focus on offshore wind turbines. Different type of faults on offshore wind turbines are reviewed, including gearbox and bearing failures, generators failures, rotor failures and electrical failures. And then two widely-used methods(vibration analysis and oil monitoring) for predictive condition monitoring and fault diagnosis in offshore wind turbines are reviewed.

Cylindrical liquid can of water and CMC was simulated by solving the governing equations for continuity, momentum and energy conservation, using “COMSOL®” multiphysical coupling field software package which based on finite element method of analysis. Through finding out cold spot of 100 ℃, 105 ℃，110℃ and 115℃ in the can and sterilization minimum value spot, temperature and sterilization value were compared. The results indicated that there were differences between cold spot and F minimum value spot. thus, in order to ensuring food safety, the original sterilization time should be moderately prolong, especially for thinlyfluid.

We report a resonant method to measure the wall capacitance (Cw) and solution resistance (RS) in a capacitively coupled contactless conductivity detector (C4D). Under the typical operating conditions in capillary electrophoresis (I.D. 50μm, O.D. 360μm, electrode length of 4mm, electrode gap of 1mm, frequency of 200kHz), the values of Cwmeasured in 1 and 20mmol/L NaCl solutions are 2.8 and 32fF, which are only 1.1% and 12% of prediction by the equation in references, respectively. The value of RSis less than the prediction in solutions with κ<0.02S/m. The response current of C4D is due to the change in Cwbecause the total impedance of a C4D is composed mainly by the impedance from Cw.

A water soluble branched polyacrylamide has been synthesized through solution polymerization. The polymerization was initiated by potassium diperiodatocuprate, K5[Cu(HIO6)2](Cu(III)), in alkaline medium and capable of initiating the self condensation vinyl polymerization of acrylamide monomer. The polymer obtained was characterized using Fourier-transform infrared (FTIR) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. Its flocculation properties were evaluated with clay suspensions using standard jar tests. The concentration of monomers, concentration of initiators, reaction temperature and solution pH on the influence of intrinsic viscosity and flocculation properties of production were studied. The results demonstrate that the branched polymer can be used as a kind of novel flocculant in water and wastewater treatment.

A series of novel sulfonated poly(arylene ether sulfone) (SPAES) copolymers were successfully synthesized from hexafluoro bisphenol A (6F-BPA), 9,9’-bis(4-hydroxyphenyl) fluorene (BHPF), 4,4’-difluorodiphenyl sulfone (DFDPS) and 3,3’-disulfonate-4,4’-difluorodiphenyl sulfone (SDFDPS) via aromatic nucleophilic substitution polymerization, and subsequently used to prepare proton exchange membranes. By adjusting the ratio of 6F-BPA to BHPF, the influence of the rigidity of polymer backbone on the properties of the prepared membranes was investigated in detail. The results indicated that the SPAES membranes had better stability towards water but lowered water uptake and proton conductivity with the increase in the polymer backbone rigidity.

The feed drive system model of NC precision sphere grinding machine (MD6040) is constructed. Although a large number of researchers pay more attention on advanced controllers, most high performance machine tools still adopt PID (Proportion Integration Differentiation) controller today. In this paper, PDF (Pseudo-Derivative Feedback) controller and PDFF (Pseudo-Derivative Control with feedforward Gain) controller which evolved from PID controller are studied. The performance of PID controller, PDF controller and PDFF controller is investigated by simulation and experiment. Both simulation results and experiment results showed that PID controller has severe overshoot and less rise time, PDF controller has strong robustness and long rise time and PDFF controller possesses the advantages of the other two controllers. PDFF controller is more suitable for NC precision sphere grinding machine feed drive system.

Thermal conductivities of two kinds of nanofluids (SiO2-water and SiO2-ethylene glycol) were measured by transient hot-wire method at different volume fraction and temperature. Influences of volume fraction of particles and temperature on thermal conductivities of nanofluids were analyzed. The Experimental results show that thermal conductivities of nanofluids are higher than those of base fluids, and increase with the increase of volume fraction and temperature. When approximately 0.5% volume fraction of SiO2 nanoparticles are added into water and ethylene glycol at the temperature 50℃, the thermal conductivities are enhanced 46.2% and 62.8% respectively.

A new Eu(III) complex Eu(phen)(DMF)2(NO3)3 (1) containing phenanthroline (phen) and DMF (N,N-dimethylformamide) as ligands has been synthesized and characterized by IR and single-crystal X-ray diffraction. The photoluminescence property of 1 is investigated to show the characteristic emission of the Eu(III) ion.

Al2O3-water nanofluids with volume concentration of 0.1%~0.5% were prepared by a two-step method, the thermophysical parameters such as thermal conductivity, viscosity and surface tension were measured, The results showed that the thermal conductivity of Al2O3-water nanofluids increased with increasing temperature and volume concentration, while the viscosity decreased with increasing temperature but increased with increasing volume concentration, in contrast to the thermal conductivity, the surface tension significantly decreased with increasing temperature and volume concentration. Furthermore, Al2O3-water nanofluids with 0.5% volume concentration were added into heat pipe. The experimental measurements showed that the Al2O3-water nanofluids have improved the heat transfer performance of heat pipe and the heat transfer coefficient of the heat pipe with Al2O3-water nanofluids enhanced by 85.7% when compared with the heat pipe with deionized water.

Aqueous nanofluids composed of alumina nanoparticles with different sizes at a concentration from 0.1vol% to 0.5vol% were prepared by a two-step method. The suspension and dispersion characteristics were experimentally examined by zeta potential, average size and absorption spectrum. The thermophysical properties such as the viscosity, surface tension, thermal conductivity, saturation vapor pressure and latent heat of vaporization were measured. The influences of the particle size, particle volume concentration and temperature on the thermophysical property were investigated. It was found that the viscosity and thermal conductivity increased with decreasing nanoparticle size. In contrast, the surface tension, saturation vapor pressure and latent heat of vaporization decrease with decreasing nanoparticle size. The viscosity, thermal conductivity and saturation vapor pressure have an increasing tendency with increasing volume concentration. However, surface tension and latent heat of vaporization showed a reverse tendency. Furthermore, the temperature also showed had obvious influence on the nanofluids viscosity, thermal conductivity and surface tension.

With elaborating the research evolvement of equipment support resource verification, this paper demonstrated the significance of operational mission to this research. It decomposed Equipment Support System (ESS) into three subsystems: operational mission system, support object system and support resources system. According to the theories of Integrated Logistics Support, the overall parameter model was established to depict the relationship and impact mechanism of ESS’s components. Focusing on the key parameter: mean logistic delay time (MLDT), this paper proposed a transformation model to convert operational mission requirements to equipment support requirements.Transformation model can predict and ascertain all support resources needed to accomplish operational mission scientifically.

Nanofluid is a new class of heat transfer fluid which contains suspended metallic or nonmetallic nanoparticles in traditional fluid. In this paper, nanofluids containing low volume concentrations (0.1-0.5vol.%) of Al2O3 and SiO2 nanoparticles were produced using a two-step method with ultrasonication and without any surfactant. Suspension stability of nanofluid was characterized and analyzed using zeta potential, average particle size and absorbancy method. The KD2-pro thermal property meter was used to measure the thermal conductivities of Al2O3(40nm)-water and SiO2(30nm)-water nanofluids at different volume concentrations (0.1-0.5vol.%) and temperature(25-50℃). The results show that adding nanoparticles into base fluid can enhance the thermal conductivity greatly. Furthermore, it is also show that the thermal conductivities increase nearly linearly with the nanoparticle volume concentration increasing, and increase significantly with the temperature increasing. A model of thermal conductivity of nanofluid, which has a much better precision, was proposed. But the values of the model are lower than the measured thermal conductivities.

This paper presents an experimental investigation of the heat transfer characteristics of the heat pipe with CuO-water nanofluid. For this purpose, CuO nanoparticles of 30 nm size were dispersed in distilled water to form stable suspension containing 0.1% ~ 2.0% mass concentrations of nanoparticles, and then the heat pipe was produced after CuO-water nanofluid was added in it as the working fluid. Experimental results show that the use of CuO-water nanofluid hold a lower start-up temperature and shorter start-up time for the evaporation section of the heat pipe compared to distilled water. Their heat transfer performance of the evaporation section and condenser section has been improved than that of distilled water. The heat transfer coefficient of nanofluid is higher than that of the base liquid and found to increase by 29.4% and 125.0% for the mass concentration of 0.5% compared with the heat pipe using distilled water while the input power ranging from 15W to 45W. By examining the thermal resistance, it was found that the thermal resistance has been significantly decreased compared with the heat pipe with distilled water. The thermal resistance of heat pipe using CuO-water nanofluid at a mass concentration of 0.5% is 0.36K/W when the input power is 45W, while the thermal resistance of heat pipe using distilled water is 0.80K/W. Further analysis indicates that the heat pipe using CuO-water nanofluid at 1.0% mass concentrations has the best heat transfer performance.

To overcome inherent resolution limitation of imaging system and provide a high resolution satellite image economically and practically, the paper researched on image super-resolution reconstruction (SRR) based on BPNN and RBFNN. Learning sample images are obtained according to image observation model, input/output mapping pairs are formed by way of vector mappings, and then two NN models of SRR are established respectively. Simulation and generalization tests are carried on the BPNN and RBFNN respectively. Results indicate that reconstruction performance of BPNN is better than that of RBFNN in aspect of reconstruction time-consuming, convergence speed and effect of SRR in generalization tests, although those parameters are better in simulation tests of RBFNN. So BPNN is more suitable for project applications of image super-resolution reconstruction.

A cyclic‐tetranuclear [Ni4(H–1L)2(μ‐PhCOO)2(H2O)4](ClO4)4·2H2O (1) complex has been prepared by reaction of nickel (II) perchlorate with L(L= 3,5‐bis((bis(2‐hydroxylethyl)amino)methyl)‐4H‐1,2,4,‐triazol‐4‐amine) and benzoate sodium. The X‐ray structure shows that complex 1consists of a cyclic tetranuclear nickel(II) cation and four uncoordinated ClO4–anions and two crystalline water molecules, in which four nickel atoms have distorted octahedral coordination. Magnetic studies indicate the existence of antiferromagnetic coupling between the nickel(II) ions. The interaction of the complex with calf thymus DNA (CT‐DNA) has been investigated by UV absorption and fluorescent spectroscopy, furthermore, DNA cleavage experiments show that the complex cleavages DNA through an oxidative mechanism.

ABSTRACTGlucose transporter 4 (GLUT4) is responsible for insulin-stimulated glucose transporting into the insulin-sensitive fat and muscle cells. The dynamics of GLUT4 storage vesicles (GSVs) remains to be explored and it is unclear how GSVs are arranged based on their mobility. We examined this issue in 3T3-L1 cells via investigating the three-dimensional mobility of single GSV labeled with EGFP-fused GLUT4. A thin layer of cytosol right adjacent to the plasma membrane was illuminated and successively imaged at 5 Hz under a total internal reflection fluorescence microscope with a penetration depth of 136 nm. Employing single particle tracking, the three-dimensional subpixel displacement of single GSV was tracked at a spatial precision of 22 nm. Both the mean square displacement and the diffusion coefficient were calculated for each vesicle. Tracking results revealed that vesicles moved as if restricted within a cage that has a mean radius of 160 nm, suggesting the presence of some intracellular tethering matrix. By constructing the histogram of the diffusion coefficients of GSVs, we observed a smooth distribution instead of the existence of distinct groups. The result indicates that GSVs are dynamically retained in a continuous and wide range of mobility rather than into separate classes.

ABSTRACTGlucose transporter 4 (GLUT4) is responsible for insulin-stimulated glucose transporting into the insulin-sensitive fat and muscle cells. The dynamics of GLUT4 storage vesicles (GSVs) remains to be explored and it is unclear how GSVs are arranged based on their mobility. We examined this issue in 3T3-L1 cells via investigating the three-dimensional mobility of single GSV labeled with EGFP-fused GLUT4. A thin layer of cytosol right adjacent to the plasma membrane was illuminated and successively imaged at 5 Hz under a total internal reflection fluorescence microscope with a penetration depth of 136 nm. Employing single particle tracking, the three-dimensional subpixel displacement of single GSV was tracked at a spatial precision of 22 nm. Both the mean square displacement and the diffusion coefficient were calculated for each vesicle. Tracking results revealed that vesicles moved as if restricted within a cage that has a mean radius of 160 nm, suggesting the presence of some intracellular tethering matrix. By constructing the histogram of the diffusion coefficients of GSVs, we observed a smooth distribution instead of the existence of distinct groups. The result indicates that GSVs are dynamically retained in a continuous and wide range of mobility rather than into separate classes.Cell Research (2004) 14, 480–486. doi:10.1038/sj.cr.7290251