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In this article, we developed a new method to analyze the complex chemical reactions induced by electron beam radiolysis based on big data analysis. At first, we built an element transport network to show the chemical reactions. Furthermore, the linearity between the species was quantified by Pearson correlation coefficient analysis. Based on the analysis, the mechanism of the high linearity between the special species pairs was interpreted by the element transport roadmap and chemical equations. The time variation of the pH of the solution and bubble formation in the solution were analyzed by simulation and data analysis. The simulation indicates that O

Purpose Endothelial dysfunction and the subsequent decrease in endothelium-dependent vascular relaxation of small arteries are major features of hypertension. Artemisinin, a well-known antimalarial drug, has been shown to exert protecting roles against endothelial cell injury in cardiac and pulmonary vascular diseases. The current study aimed to investigate the effects of artemisinin on endothelium-dependent vascular relaxation and arterial blood pressure, as well as the potential signalling pathways in spontaneously hypertensive rats (SHRs). Methods In this study, acetylcholine (ACh)-induced dose-dependent relaxation assays were performed to evaluate vascular endothelial function after treatment with artemisinin. Artemisinin was administered to the rats by intravenous injection or to arteries by incubation for the acute exposure experiments, and it was administered to rats by intraperitoneal injection for 28 days for the chronic experiments. Results Both acute and chronic administration of artemisinin decreased the heart rate and improved ACh-induced endothelium-dependent relaxation but negligibly affected the arterial blood pressure in SHRs. Incubation with artemisinin decreased basal vascular tension, NAD(P)H oxidase activity and reactive oxygen species (ROS) levels, but it also increased endothelial nitric oxide (NO) synthase (eNOS) activity and NO levels in the mesenteric artery, coronary artery, and pulmonary artery of SHRs. Artemisinin chronic administration to SHRs increased the protein expression of eNOS and decreased the protein expression of the NAD(P)H oxidase subunits NOX-2 and NOX-4 in the mesenteric artery. Conclusion These results indicate that treatment with artemisinin has beneficial effects on reducing the heart rate and basal vascular tension and improving endothelium-dependent vascular relaxation in hypertension, which might occur by increasing eNOS activation and NO release and inhibiting NAD(P)H oxidase derived ROS production., Graphical Abstract

Purpose: The hyper-proliferation, promoted migration, fibrosis, and calcification of pulmonary arterial smooth muscle cells (PASMCs) play critical roles in pulmonary artery (PA) continuous contraction and vascular remodeling, leading to elevated pulmonary arterial resistance and pulmonary hypertension (PH). In this study, we sought to ascertain the effects of a TOR2A gene product, salusin-β, on PASMCs’ proliferation, migration, fibrosis, calcification, and the imbalance of vasomotor function as well as pulmonary vascular remodeling in monocrotaline (MCT)-induced PH rats and their underlying mechanisms.Methods: Knockdown or overexpression of salusin-β in rats or PASMCs was performed through tail vein injection or cell transfection of virus. The right ventricular systolic pressure (RVSP) of the rat was measured by right ventricle catheterization. Sodium nitroprusside (SNP) or acetylcholine (ACh)-induced dose-dependent relaxation was used to evaluate the vasodilatation function. Primary PASMCs were isolated from the PAs of control and PH rats.Results: The salusin-β protein expressions were significantly increased in PAs and PASMCs isolated from PH rats compared with control rats. Knockdown of salusin-β in rats decreased high K+ solution-induced contraction, RVSP and RV hypertrophy index, improved SNP or ACh-induced vascular relaxation of PAs, and relieved vascular remodeling and calcification of PAs from PH rats. Silencing salusin-β in PASMCs isolated from PH rats alleviated the proliferation, migration, fibrosis, and calcification, as well as the NAD(P)H oxidase activity and reactive oxygen species (ROS) level. Overexpression of salusin-β exerted the opposite effects on vasomotor function and vascular remodeling, and PASMCs proliferation, migration, fibrosis and calcification.Conclusion: Increased salusin-β activity in PAs from PH rats contributes to PASMCs proliferation, migration, fibrosis, and calcification, leading to the imbalance of vascular contraction and relaxation and vascular remodeling through stimulating the production of NAD(P)H oxidase derived ROS.

Background Soft tissue sarcoma is a rare and highly heterogeneous tumor in clinical practice. Pathological grading of the soft tissue sarcoma is a key factor in patient prognosis and treatment planning while the clinical data of soft tissue sarcoma are imbalanced. In this paper, we propose an effective solution to find the optimal imbalance machine learning model for predicting the classification of soft tissue sarcoma data. Methods In this paper, a large number of features are first obtained based on $$T_1$$ T 1 WI images using the radiomics methods.Then, we explore the methods of feature selection, sampling and classification, get 17 imbalance machine learning models based on the above features and performed extensive experiments to classify imbalanced soft tissue sarcoma data. Meanwhile, we used another dataset splitting method as well, which could improve the classification performance and verify the validity of the models. Results The experimental results show that the combination of extremely randomized trees (ERT) classification algorithm using SMOTETomek and the recursive feature elimination technique (RFE) performs best compared to other methods. The accuracy of RFE+STT+ERT is 81.57% , which is close to the accuracy of biopsy, and the accuracy is 95.69% when using another dataset splitting method. Conclusion Preoperative predicting pathological grade of soft tissue sarcoma in an accurate and noninvasive manner is essential. Our proposed machine learning method (RFE+STT+ERT) can make a positive contribution to solving the imbalanced data classification problem, which can favorably support the development of personalized treatment plans for soft tissue sarcoma patients.

Background: Soft tissue sarcoma is a rare and highly heterogeneous tumor in clinical practice. Pathological grading of the soft tissue sarcoma is a key factor in patient prognosis and treatment planning while the clinical data of soft tissue sarcoma are imbalanced. In this paper, we propose an effective solution to find the optimal imbalance machine learning model for predicting the classification of soft tissue sarcomas data. Methods: In this paper, a large number of features are first obtained based on T1WI images using the radiomics methods. Then, we explore the combinations of different sampling techniques, feature selection methods, and classification algorithms, and get nine imbalance machine learning models based on the above features. The receiver operating characteristic curve model is used to evaluate the performance of these nine methods on predicting the pathological grade of soft tissue sarcoma. Results: The experimental results show that the combination of extremely randomized trees classification algorithm using random oversampling examples (ROSE) and the recursive feature elimination technique performs best compared to other combination methods. The receiver operating characteristic area under the curve, accuracy, sensitivity, specificity and G-mean of this method for predicting high-grade versus low-grade soft tissue sarcoma are 0.9457, 94.61%, 93.55%, 95.59% and 0.9456, respectively. Conclusion: Preoperative predicting pathological grade of soft tissue sarcomas in an accurate and noninvasive manner is essential. Our proposed machine learning method can make a positive contribution to solving the imbalanced data classification problem, which can favorably support the development of personalized treatment plans for soft tissue sarcoma patients.

As serine/threonine protein kinases, mitogen-activated protein kinases (MAPK) take part in cellular metabolism. This work found 14 MAPK genes in the yellow catfish (Pelteobagrus fulviadraco) genome and evaluated their taxonomy, conserved domains and evolutionary linkages for a better understanding of the MAPK gene family's evolutionary relationship and antibacterial immune response. The findings revealed that several MAPK genes are activated in response to immunological and inflammatory responses. Collinearity research revealed that in yellow catfish and zebrafish, there are six pairs of highly similar MAPK genes, indicating that these genes have been more conserved throughout evolution. The MAPK gene quantification findings revealed that JNK1a, JNK1b, p38delta and p38alpha b expression levels were considerably upregulated, indicating that they act in fish innate immunity. The findings implied that MAPK genes may involve in defence against detrimental microbe in yellow catfish, which will help researchers better understand how MAPK genes work in the innate immune system.

The MADS-box gene plays an important role in plant growth and development. As an important vegetable of Cucurbitaceae, chayote has great edible and medicinal value. So far, there is little molecular research on chayote, and there are no reports on the MADS-box transcription factor of chayote. In this study, the MADS-box gene family of chayote was analyzed for the first time, and a total of 70 MADS-box genes were identified, including 14 type I and 56 type II MICK MADS genes. They were randomly distributed on 13 chromosomes except for chromosome 11. The light response element, hormone response element and abiotic stress response element were found in the promoter region of 70 MADS genes, indicating that the MADS gene can regulate the growth and development of chayote, resist abiotic stress, and participate in hormone response; GO and KEGG enrichment analysis also found that SeMADS genes were mainly enriched in biological regulation and signal regulation, which further proved the important role of MADS-box gene in plant growth and development. The results of collinearity showed that segmental duplication was the main driving force of MADS gene expansion in chayote. RNA-seq showed that the expression levels of SeMADS06, SeMADS13, SeMADS26, SeMADS28, SeMADS36 and SeMADS37 gradually increased with the growth of chayote, indicating that these genes may be related to the development of root tubers of ‘Tuershao’. The gene expression patterns showed that 12 SeMADS genes were specifically expressed in the male flower in ‘Tuershao’ and chayote. In addition, SeMADS03 and SeMADS52 may be involved in regulating the maturation of male flowers of ‘Tuershao’ and chayote. SeMADS21 may be the crucial gene in the development stage of the female flower of ‘Tuershao’. This study laid a theoretical foundation for the further study of the function of the MADS gene in chayote in the future.

Cs-doped α-Bi2O3 was synthesized via a facile hydrothermal reaction. The phase formations of the samples were investigated via X-ray powder diffraction (XRD) patterns and structural refinements. The samples present well-crystalized microplates with smooth surfaces and a thickness about 300 nm. The experiments revealed that the undoped and Cs-doped α-Bi2O3 microplates could crystallized in a pure monoclinic phase. The band gap of α-Bi2O3 could be reduced via the Cs-doping in the lattices. The photocatalytic activity on photo-degradation of methylene blue (MB) was significantly improved with the Cs-doping. The effective photocatalysis was discussed on the improved visible-light response, the enhanced dispersion in the valence band composed of hybrid orbitals of Bi6s, O2p and Cs3d, and the lowered electron–hole recombination.

In the present study, BiNb5O14 and BiNb5O14/Nb2O5 heterojunction were prepared with co-precipitation synthesis. The crystal structure was studied via XRD patterns and Rietveld refinements, which has a typical tetragonal tungsten bronze (TTB)-type structure. The samples crystallized in micorods with a length of 1–4 µm and a diameter about 1 µm. As an indirect transition semiconductor, BiNb5O14 has a band energy of 2.81 eV with the valence-band formed by hybridized O-2p and Bi-6s, and the conduction band formed by Nb(6d) orbitals. The photocatalysis abilities of BiNb5O14 and BiNb5O14/Nb2O5 heterojunctions were evaluated via the photo-degradation of dye solutions. The photocatalytic activities were significantly improved via coupling BiNb5O14 with Nb2O5. In the photocatalysis reactions, •OH was the main reactive species, and the immigration rate of light-created charge-carriers was greatly improved via the heterojunction structure. The luminescence and decay lifetime were measured to discuss the photocatalysis mechanism.

Salusin-β is a biologically active peptide with 20 amino acids that exerts several cardiovascular activity-regulating effects, such as regulating vascular endothelial function and the proliferation of vascular smooth muscle cells. However, the regulatory effects of salusin-β in myocardial infarction-induced chronic heart failure (CHF) are still unknown. The current study is aimed at investigating the effects of silencing salusin-β on endothelial function, cardiac function, vascular and myocardial remodeling, and its underlying signaling pathways in CHF rats induced by coronary artery ligation. CHF and sham-operated (Sham) rats were subjected to tail vein injection of adenoviral vectors encoding salusin-β shRNA or a control-shRNA. The coronary artery (CA), pulmonary artery (PA), and mesenteric artery (MA) were isolated from rats, and isometric tension measurements of arteries were performed. Compared with Sham rats, the plasma salusin-β, leptin and visfatin levels and the salusin-β protein expression levels of CA, PA, and MA were increased, while the acetylcholine- (ACh-) induced endothelium-dependent vascular relaxation of CA, PA, and MA was attenuated significantly in CHF rats and was improved significantly by salusin-β gene knockdown. Salusin-β knockdown also improved cardiac function and vascular and myocardial remodeling, increased endothelial nitric oxide synthase (eNOS) activity and nitric oxide (NO) levels, and decreased NAD(P)H oxidase activity, NOX-2 and NOX-4 expression, and reactive oxygen species (ROS) levels in arteries in CHF rats. The effects of salusin-β knockdown in CHF rats were attenuated significantly by pretreatment with the NOS inhibitor L-NAME. These results indicate that silencing salusin-β contributes to the improvement of endothelial function, cardiac function, and cardiovascular remodeling in CHF by inhibiting NAD(P)H oxidase-ROS generation and activating eNOS-NO production.

A facile strategy to boost anticorrosion potency of graphene oxide/silica hybrid sol-gel coating is developed through fully exploiting the capabilities of graphene oxide (GO). Together with a barrier to corrosives and crack inhibitor, GO was further explored herein as a regulator to regulate the gelation process and provide robust coating films with stratified microstructures and ultimately extended diffusion paths. The sol-gel coating with stratified microstructure achieved on AA5052 aluminum alloy surface afforded greatly enhanced corrosion protection capability as assessed by electrochemical measurements and immersion tests. The corrosion current density of the sample of a hybrid GO sol-gel film was about 30 times less than that of sample of pure sol-gel film sample. The regulation mechanism of GO during the film formation process and the anticorrosive protection properties of the film were discussed.

In 4 FeTi 3 O 13.5 (InTi 0.75 Fe 0.25 O 3.375 ) semiconductor was prepared via sol-gel citrate-complexation synthesis. This ferrotitanate derives from a solid-solution with InFeO 3 :In 2 Ti 2 O 7 = 2:3. Phase formation and crystal structure of the sample were confirmed via XRD Rietveld refinement. Structural analyses indicated that there were two dimensional layers in the structure. The mutual repulsion in the layers induces great displacements of oxygen ions. The optical properties of In 4 FeTi 3 O 13.5 nanoparticles were investigated. The direct allowed band gap (2.56 eV) shows a characteristic charge-transfer (CT) transitions of (O2p + Fe3d) → (Ti/Fe)3d in visible-light region. The band structure and energy positions were discussed. In 4 FeTi 3 O 13.5 nanoparticles are demonstrated to be efficient for the photodegradation of Rhodamine B (RhB) under visible light irradiation (λ > 420 nm). The photocatalytic activities were attributed to the special layer structure and the catalytic mediators of multivalent Ti 4+/3+ and Fe 3+/2+ confirmed by XPS measurements.

Silver-containing niobate AgNb7O18 nanoparticles were prepared via sol-gel polymerized complex synthesis. The sample was given a good XRD Rietveld refinement in a typical perovskite-like structure. The detailed surface properties of AgNb7O18 nanoparticles were tested by SEM, EDS, TEM, nitrogen adsorption-desorption isotherms and XPS measurements. AgNb7O18 is characterized via a direct transition and the band energy is 2.76 eV. The hybridization between O 2p and Ag 3d states in valence band contributes to the narrowed band gap. The first principles electronic structure elucidation supports the narrow band gap of AgNb7O18. The sample shows an efficient degradation of methylene blue dye (MB) solutions. The trapping tests were performed to elucidate the real active species in the photocatalytic reactions. The results indicate that the superoxide radical is the main active species in the photocatalytic system, and the photocatalyst also shows a good stability and durability.

This work improved the optical absorption and photocatalytic ability of four-layered Aurivillius Bi5Ti3FeO15 through microstructural modification via partial substitution of Ti4+ with Fe3+. Bi5Ti3−xFe1+xO15 (x = 0–0.6) photocatalysts were prepared through sol-gel citrate-complexation synthesis. The sample crystallized into plate-like nanoparticles with [001] facets. Phase formation and crystal structure were confirmed via X-ray powder diffraction (XRD) Rietveld refinements. Bi5Ti3−xFe1+xO15 (x = 0–0.6) maintained its structural characteristic, i.e., a perovskite unit of (Bi3Ti3−xFe1+xO13)2– sandwiched by two (Bi2O2)2+ layers along c axis. The samples were investigated via scanning electron microscope (SEM), transmission electron microscope (TEM), energy-dispersive X-ray spectroscopy (EDX), and specific surface area analyses. The band gap showed characteristic transitions from the valence band (VB) of (O2p+Fet2 g+Bi6s) to the conduction band (CB) of (Ti-3d+Fe-eg). With increasing substitution of Ti4+ with Fe3+, the sample greatly red shifted its absorption edges. The d–d transitions in FeO6 greatly contribute to the narrow band-gap. Aurivillius is a potential photocatalyst and demonstrated photodegradation of Rhodamine B (RhB) under visible light irradiation (λ > 420 nm). Such photocatalytic activities were attributed to the special structural layer and the catalytic mediators of multivalent Ti4+/3+ and Fe3+/2+ ions in the perovskite slabs as confirmed by XPS measurements. Results suggested that substitution of Ti4+ with Fe3+ in an Aurivillius phase was an efficient method to modify the bandwidth and structure of Aurivillius phase. This phenomenon can be used as a strategy to improve the photochemical properties of Ti/Fe-containing Aurivillius phases.

Ag-containing niobate AgNb13O33 has been prepared by the sol–gel polymerized complex method. The structure was investigated via a good XRD Rietveld refinement in a typical perovskite-like framework. The morphological properties of the AgNb13O33 nanoparticles were tested via transmission electron microscopy (TEM), scanning electron microscope (SEM), and energy dispersive spectra (EDS) measurements. AgNb13O33 is a typical direct allowed semiconductor with band energy of 2.81 eV, which is much narrower than 3.4 eV of Nb2O5. This silver niobate can harvest both UV and near UV light, which is benefited from the (O-2p/Ag-4d) hybridization in the valence band. The photocatalytic abilities of AgNb13O33 nanoparticles were reported. The sample presents more efficient photocatalytic effects on photo-degradation of methylene blue (MB) dye solutions than that of Nb2O5. The photocatalytic mechanism was discussed on band energy levels, trapping experiments, photoluminescence and the decay lifetime.

A new ferrotitanate semiconductor NaFeTi 3 O 8 was developed by sol−gel citrate complexation synthesis. The sample preferentially developed into nanorods. The nanorods showed good XRD Rietveld refinements in the isostructure with Na 0.2 TiO 2 . The structure retains the two-dimensional layers of (Fe/Ti)O 6 octahedra and one-dimension channels in the structure. SEM, TEM, EDS, and specific surface area analysis were employed to characterize the samples. Results showed that the optical absorption of NaFeTi 3 O 8 nanorods is in the visible wavelength region. The direct allowed bandgap (2.12 eV) shows the characteristic charge-transfer transitions of O 2p/Fe 3d→(Ti/Fe) 3d. The d–d allowed transitions in the FeO 6 octahedron presented considerable contributions to the narrow bandgap. NaFeTi 3 O 8 exhibited potential as a photocatalyst for RhB photodegradation under visible light excitation ( λ > 420 nm). Photocatalytic activities are discussed in relation to the structural properties.

Ni-doped Cu2(OH)3Cl microcrystals were prepared by a facile hydrothermal synthesis without the help of any additive inorganic or organic reagent. The micro-particles were investigated by X-ray powder diffraction (XRD) with Rietveld refinement, scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–vis optical absorption, and X-ray photoelectron spectroscopy (XPS) etc. Ni-doping could well stabilize the Cu2(OH)3Cl paratacamite phase at ambient temperature. The band structure and energy positions of Ni-doped Cu2(OH)3Cl microparticles were investigated. The band gap of Cu2(OH)3Cl could be greatly decreased by Ni-doping. The conduction band bottom of Ni-doped Cu2(OH)3Cl is lower and possesses greater dispersion than that of pure Cu2(OH)3Cl. The photocatalytic activity of Ni-doped Cu2(OH)3Cl micro-particles was evaluated by the photodegradation of Rhodamine B (RhB) dye under visible-light irradiation. The Ni-doping increases the photocatalytic activity of Cu2(OH)3Cl. The photocatalytic activity was discussed on the base of the structural and electronic characteristics. Keywords: Photocatalyst, Optical properties, Semiconductors, Band structure, Copper oxide

In this research, instrumented spherical micro-indentation/scratch tests were conducted to investigate microscopic mechanical properties of multilayer graphene (MLG) reinforced titanium based metal matrix composites (TiMMCs) synthesized using spark plasma sintering (SPS). Raman spectra and microstructure observation illustrated that MLGs survive the harsh SPS processing conditions and homogeneously distribute in Ti matrix. Instrumented indentation and scratch tests showed that mechanical properties in microscopic scale of MLG reinforced TiMMCs such as indentation yield strength and scratch resistance are significantly improved. The computed results corroborated that the critical length of most of the added MLGs satisfies the criterion of critical length of the reinforcement, and the strengthening mechanisms including enhanced dislocation density and Orowan mechanism play significant roles in the improved mechanical properties. This research is expected to facilitate a better understanding of mechanical behavior in microscopic scale of MLG reinforced metal matrix composites. Keywords: Graphene, Metal-matrix composites, Micro-mechanics, Mechanical testing, Sintering

Primary mono-amine (furfuryl amine) is functionalized as a chain extender to obtain linear polyurethane bearing pendant furan groups (L-PU-Furan), unlike the previous research (furanic diols as chain extender). Furfuryl amine can functionalize as a chain extender due to the reactivity between the resultant urea group and NCO group at higher temperatures. Pendant cross-linked polyurethane containing a DA bond (C-PU-DA) is obtained from the cross-linking of L-PU-Furan and a bismaleimide (BMI) via a Diels–Alder reaction. L-PU-Furan and C-PU-DA are characterized by 1H NMR, FTIR, DSC and TGA. The results of 1H NMR and gel–solution–gel experiments demonstrate that the C-PU-DA exhibits excellent thermal reversibility. C-PU-DA exhibits good healable properties as evidenced by the evolution of a crack versus temperature observed under polarizing optical microscopy. C-PU-DA exhibits good mechanical properties and healing efficiency, determined by breaking (tensile) strength measurements.

Linear polyurethane was synthesized by Diels–Alder (DA) reaction between a polyurethane prepolymer end-capped with furan rings (MPF) and bismaleimide (BMI). The polymerization kinetics were studied following a preliminary kinetic study of the DA reaction between furfuryl alcohol (FA) and BMI compounds by attenuated total reflection infrared, ultraviolet–visible and in situ 1H NMR spectroscopies, where in situ 1H NMR spectroscopy was selected as the analytical method of choice to study the DA reaction between MPF and BMI. The results showed that the reaction followed second-order kinetics, and the most beneficial experimental conditions to maximize conversion were identified.

A proliferation-inducing ligand (APRIL) is a novel member of the tumor necrosis factor (TNF) superfamily, which is involved in immune regulation. In the present study, the full-length cDNA of APRIL (designated bAPRIL) from bat was cloned using RT-PCR and its biological activities have been characterized. The open reading frame (ORF) of this cDNA consists of 753 bases, encoding a protein of 250 amino acids. This protein was found to contain a predicted transmembrane domain, a putative furin protease cleavage site, and a typical TNF homology domain corresponding to other, known APRIL homologs. Real-time quantitative PCR (qPCR) analysis indicated that bAPRIL mRNA was predominantly expressed in bat lymphoid tissue spleen. The SUMO-bsAPRIL was efficiently expressed in Escherichia coli BL21 (DE3) and confirmed by SDS-PAGE and Western blot analysis. Laser scanning confocal microscopy analysis showed that bsAPRIL could bind to its receptors on B cells. In vitro, MTT assays indicated that bsAPRIL could promote the survival/proliferation of mouse splenic B cells grown with anti-mouse IgM. These findings indicate that bsAPRIL plays an important role in the survival and proliferation of B cells and has functional cross-reactivity among mammalians. The present findings may provide valuable information for research into the immune system of the bat.

Crosslinked self-healing polyurethane/urea based on a Diels-Alder reaction (C-PMPU-DA) was synthesized from a multiple-furan monomer and a commercial bismaleimide. The multiple-furan monomer (PMPU-furan) was obtained from a func- tionalized prepolymer (polymeric MDI: PBA-2000 52:1) by furfuryl amine. The structures of both the PMPU-furan and C-PMPU- DA were characterized by attenuated total reflectance (ATR)-Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and 1 H-NMR. The Diels-Alder bonds enabled C-PMPU-DA thermal reversibility, which was investigated by ATR-FTIR spectroscopy, 1 H-NMR, gel-solution-gel experiments, and viscosity tests. Meanwhile, the self-healing prop- erties of C-PMPU-DA were also investigated by the recovery of the mechanical properties. The results showed that C-PMPU-DA exhibited good thermal reversibility and self-healing properties. C-PMPU-DA exhibited thermosetting properties at room tempera- ture, although it exhibited thermoplastic properties at higher temperatures and may find applications in self-healing materials, recy- clable materials, or removable materials. V C 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40234.

We applied a ribosome display technique to a mouse single chain variable fragment (scFv) library to select scFvs specific for the inducible costimulator (ICOS). mRNA was isolated from the spleens of BALB/c mice immunized with ICOS protein. Heavy and κ chain genes (VH and κ) were amplified separately by reverse transcriptase polymerase chain reaction, and the anti-ICOS VH/κ chain ribosome display library was constructed with a special flexible linker by overlap extension PCR. The VH/κ chain library was transcribed and translated in vitro using a rabbit reticulocyte lysate system. Then, antibody–ribosome–mRNA complexes were produced and panned against ICOS protein under appropriate conditions. However, in order to isolate specific scFvs for ICOS, negative selection using CD28 was carried out before three rounds of positive selection on ICOS. After three rounds of panning, the selected scFv DNAs were cloned into pET43.1a and detected by SDS-PAGE. Then, enzyme-linked immunosorbent assay showed that we successfully constructed a native ribosome display library, and among seven clones, clone 5 had the highest affinity for the ICOS and low for the CD28. Anti-ICOS scFvs are assessed for binding specificity and affinity and may provide the potential for development of the humanized and acute and chronic allograft rejection.

According to the traffic sign recognition process converges slowly, easy to fall into local minimum of defects in general BP algorithm, a BP algorithm is discussed in the paper, which is based on the improved conjugate gradient method on the basis of Fletcher-Reeves linear search method. At the beginning, the basic principle of the algorithm is introduced; meanwhile, an in-depth analysis is discussed from the theoretical aspects in the paper, and then the trained BP neural network is applied into the function approximation. Experimental results show that the algorithm has many advantages, such as it has a good effect in solving the rotation and scale invariance with the image, the extracted features with translation, scale and rotation invariance. The fast convergence speed and less iteration of this algorithm can meet the requirements of unmanned vehicle autonomous navigation.

According to the integration calibration problem for planet rover stereo vision, a transformation method form vision reference frame to rover reference frame based on theodolite is investigated in this paper which can transform the 3D measure results into rover reference frame. The integration calibration experiment results based on real planet rover show that this method possesses high localization precision and practicable value.

A dynamic voltage restorer (DVR) is a power-electronic controller that can protect sensitive loads from disturbances in the supply system. It is a static series compensator (SSC) suitable for protecting industrial plants against voltage sag. Considering the decaying DC component in fault signal impacts the real-time performance and compensation accuracy of voltage compensation detection. This paper presents a semi-period algorithm and a three-point algorithm. Both of the two algorithms can quickly extract fundamental component from fault signal. After the fundamental positive-sequence voltage is extracted by the instantaneous decomposition link, the voltage compensation can be calculated through the direct-detecting algorithm. The simulation results prove the two algorithms can filter the decaying DC component and just needs a small amount of calculation. It has great potential for practical applications.

Rescent years, some DG (distributed generation) have been introduced in distribution systems, and the voltage violation problem has been at stake for the distribution system. The impact of DG integration on distribution system is studied in this paper, and the transient stability mechanism of DG is analyzed theoretically. This paper investigates the dynamic analysis of a DVR when applied to correct the voltage distortion in distribution system. Then the model of DG is built by Matlab/Simulink. And it is used to study the impact of DG integration on the distribution system. Then the voltage regulation-dynamic voltage restorer (DVR) is introduced to distribution network with distributed generation. A calculation method for DVR in distribution system with distributed generation is proposed, which is based on a semi-period algorithm to extract fundamental component from fault signal then extract the fundamental positive sequence voltage by the decomposition instantaneous link, and then the quantity of voltage compensation can be solved by direct detection algorithm. Simulation results show that the introduction of DVR (dynamic voltage restorer) to the distribution system with distributed generation is good for voltage regulation and making a good guarantee of the voltage quality of sensitive loads; and the algorithm for DVR is simple and effective.

The working principle of active power factor correction (APFC) technology is expounded. To eliminate harmonics and reactive current during the charging process of DC energy storage unit of the dynamic voltage restorer (DVR), leading APFC technology into the voltage control of DC energy storage unit of dynamic voltage restorer, the digital voltage control algorithm for DC energy storage unit of DVR is proposed and the design approach for voltage controller and current controller is given. Simulation results show that by use of APFC technology the harmonics and reactive current in charging current of DVR can be actively eliminated and both voltage stability and dynamic response of DC energy storage unit can be improved.

Because the compensation signals of DVR are unpredictable, this paper advanced a deadbeat control algorithm for DVR voltage waveform tracking compensation. On the basis of state equations and state variables information of the system, a specific scheme is produced to realize voltage waveform tracking compensation, which includes a state observer a voltage forecast and a current forecast for a random load. The switch control signals of next sampling period are calculated so that the output voltage can track the reference voltage synchronously. The simulation results show that this control algorithm is correct and feasible. (6 pages)

New linear polyurethane was synthesized via a Diels–Alder (DA) reaction between a polyurethane prepolymer end-capped with furan groups (MPF) and bismaleimide (BMI). The structure of the linear polyurethane with DA bonds was characterized by 1H NMR, ATI-FTIR, TGA and AFM. The introduction of DA bonds enables the polyurethane thermal reversibility, which was studied thoroughly by 1H NMR, DSC and GPC. Besides, the new linear polyurethane with DA bonds also exhibits self-healing properties under heat treatment, which was observed by polarized optical microscope. The self-healing efficiency determined by the recovery of breaking tensile strength after being damaged and healed can reach up to 80%.

With the start of trial operation of direct purchasing electricity for large consumers in China, the method on how to allocate the wheeling charges of large consumers is of vital theoretical and practical significance. An integrated method for allocating the congestion management cost of larger consumers is presented in this paper considering time-of-use (TOU) pricing in congestion period, power supply reliability and the use capacity of the line. Modeling the TOU index, power supply reliability index and use capacity of the line index is proposed. The weights of three indices are determined by interacting between the transmission utility and large consumers based on multilevel models to get comprehensive evaluation indices for all consumers. The integrated indices are used to allocate the cost. Test results show that the method can allocate the congestion cost more reasonably.