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With the increasing utilization of electronic equipment in the power system, sub-synchronous oscillation (SSO) has occurred many times and caused off-grid accidents because of power oscillation. SSO has become one of the main problems that restrict the development of new energy. In this paper, power oscillation in grid-side converters (GSCs) in doubly-fed induction generators (DFIGs) under SSO is studied. Firstly, the influence mechanism of SSO on GSC multipath disturbance is studied. Secondly, the problem of coupling oscillation caused by PLL output errors after coordinate transformation is studied, and the mathematical model of GSC output power considering SSO multipath disturbance is established. By analyzing the oscillation suppression ability of the quasi-resonant controller under variable SSO states, the key influencing factors of SSO for GSC power oscillation suppression strategies are determined. Furthermore, based on the above theoretical analysis and research, an improved PLL is designed to eliminate the influence of its output errors on the disturbance of GSC. At the same time, a DFIG-GSC power oscillation suppression strategy using an adaptive quasi-resonant controller is designed to eliminate the influence of SSO on the multi-path disturbance of GSC. Finally, the effectiveness of the proposed suppression strategy is verified using simulation and experimental results.

Due to fewer conduction devices in operating condition, the bridgeless power factor correction (PFC) converter is more efficient than the traditional PFC circuit. However, to achieve a low output voltage ripple on the DC side, a large electrolytic capacitor must be connected in parallel to the output end. To reduce the value of capacitance, this paper proposes a dual-boost bridgeless PFC converter with a bidirectional buck/boost power decoupling converter in the latter stage. The bidirectional converter absorbs double-line-frequency ripple, lowering the power pulsation at the output end while realizing power decoupling. The one-cycle control is adopted in bridgeless PFC converter, so that the input current can follow the input voltage to achieve power factor correction and decrease harmonic pollution. The power decoupling circuit is designed with a voltage outer loop using PI control and a current inner loop using model predictive current control, which alleviates the output voltage fluctuation caused by the reduction of the capacitance value of the filter capacitor, for the purpose of realizing non-electrolytic capacitor. Finally, the topology and control strategy involved in this paper are simulated and experimented to verify the validity and superiority of the theory.

Supplemental material, sj-pdf-1-imr-10.1177_03000605221147434 for The inflammatory cytokine profiles and ocular biometric characteristics of primary angle-closure glaucoma by Hong-Bo Zeng, Jun-Di Jiang, Rong Li, Jian Li, Wen-Juan Zeng, Xiong-Kai Li, Bin Hu, Fei Zhou, Hai-Ying Yu, Jian-Guo Xie, Zhi-Neng Ning and Xian Wang in Journal of International Medical Research

Supplemental material, sj-pdf-1-imr-10.1177_03000605221147434 for The inflammatory cytokine profiles and ocular biometric characteristics of primary angle-closure glaucoma by Hong-Bo Zeng, Jun-Di Jiang, Rong Li, Jian Li, Wen-Juan Zeng, Xiong-Kai Li, Bin Hu, Fei Zhou, Hai-Ying Yu, Jian-Guo Xie, Zhi-Neng Ning and Xian Wang in Journal of International Medical Research

Supplemental material, sj-pdf-2-imr-10.1177_03000605221147434 for The inflammatory cytokine profiles and ocular biometric characteristics of primary angle-closure glaucoma by Hong-Bo Zeng, Jun-Di Jiang, Rong Li, Jian Li, Wen-Juan Zeng, Xiong-Kai Li, Bin Hu, Fei Zhou, Hai-Ying Yu, Jian-Guo Xie, Zhi-Neng Ning and Xian Wang in Journal of International Medical Research

Supplemental material, sj-pdf-2-imr-10.1177_03000605221147434 for The inflammatory cytokine profiles and ocular biometric characteristics of primary angle-closure glaucoma by Hong-Bo Zeng, Jun-Di Jiang, Rong Li, Jian Li, Wen-Juan Zeng, Xiong-Kai Li, Bin Hu, Fei Zhou, Hai-Ying Yu, Jian-Guo Xie, Zhi-Neng Ning and Xian Wang in Journal of International Medical Research

ObjectiveTo examine multiple genotypes ofOphiocordyceps sinensisin a semi-quantitative manner in the stromal fertile portion (SFP) densely covered with numerous ascocarps and ascospores of naturalCordyceps sinensisand to outline the dynamic alterations of the coexistingO. sinensisgenotypes in different developmental phases.MethodsMatureCordyceps sinensisspecimens were harvested and continuously cultivated in our laboratory (altitude 2,254 m). The SFPs (with ascocarps) and fully and semi-ejected ascospores were collected for histological and molecular examinations. Biochip-based single nucleotide polymorphism (SNP) MALDI-TOF mass spectrometry (MS) was used to genotype multipleO. sinensismutants in the SFPs and ascospores.ResultsMicroscopic analysis revealed distinct morphologies of the SFPs (with ascocarps) before and after ascospore ejection and SFP of developmental failure, which, along with the fully and semi-ejected ascospores, were subjected to SNP MS genotyping analysis. Mass spectra showed the coexistence of GC- and AT-biased genotypes ofO. sinensisthat were genetically and phylogenetically distinct in the SFPs before and after ejection and of developmental failure and in fully and semi-ejected ascospores. The intensity ratios of MS peaks were dynamically altered in the SFPs and the fully and semi-ejected ascospores. Mass spectra also showed transversion mutation alleles of unknown upstream and downstream sequences with altered intensities in the SFPs and ascospores. Genotype #5 of AT-biased Cluster-A maintained a high intensity in all SFPs and ascospores. An MS peak with a high intensity containing AT-biased Genotypes #6 and #15 in pre-ejection SFPs was significantly attenuated after ascospore ejection. The abundance of Genotypes #5–6 and #16 of AT-biased Cluster-A was differentially altered in the fully and semi-ejected ascospores that were collected from the sameCordyceps sinensisspecimens.ConclusionMultipleO. sinensisgenotypes coexisted in different combinations with altered abundances in the SFPs prior to and after ejection, the SFP of developmental failure, and the two types of ascospores ofCordyceps sinensis, demonstrating their genomic independence. Metagenomic fungal members present in different combinations and with dynamic alterations play symbiotic roles in different compartments of naturalCordyceps sinensis.

The high-frequency signal injection-type maximum torque per ampere (MTPA) algorithm is usually employed to control the operation of interior permanent magnet synchronous motors (IPMSMs). The MTPA algorithm exhibits good dynamic performance and anti-interference ability. However, due to the injection of a high-frequency current signal, problems such as torque ripple and additional loss are encountered. Therefore, in this paper, a virtual signal injection control (VSIC) method that does not require actual injection is proposed for solving the aforementioned problems while yielding good performance. However, in the control process of the proposed method, the d-axis inductance parameter affects the accuracy of the torque information, resulting in errors in the system. To solve this problem, an online identification algorithm of model reference adaptive systems (MRAS) based on the Popov super stability theory as the basis for the design of the adaptive law is proposed in this paper. The d-axis inductance parameter of the motor is obtained in real-time and then introduced into the control system by using the VSIC method. Finally, VSIC-type MTPA control based on inductance identification is realized. The proposed algorithm does not depend on the design parameters of the motor and exhibits good dynamic response and anti-interference performance.

Due to the symmetrical structure, consistent working characteristics in the forward and reverse operations, and good soft-switching characteristics, bidirectional CLLLC resonant converters are widely used in electric vehicles and other fields. To meet the requirements of the on-board charger, this paper uses a bidirectional CLLLC resonant converter as the rear-stage of the on-board charger. The converter uses a constant voltage and constant current control in the forward operation and voltage and current double-closed-loop control in the reverse operation. Aiming at the problem whereby the voltage gain range of the bidirectional CLLLC resonant converter is relatively narrow under frequency-conversion control, the paper proposed a hybrid control method of frequency conversion and phase shift. Frequency-conversion control is used when the voltage gain is high, and phase-shift control is used when the voltage gain is low. The output voltage range of the converter is effectively broadened, and zero voltage switching and zero current switching can be realized in the full load range to improve operating efficiency. A 3.3 kW bidirectional CLLLC resonant converter simulation system is built in the simulation software. The simulation results verify the correctness and feasibility of the designed circuit and control method.

Objective To examine the differential occurrence of Ophiocordyceps sinensis genotypes in the stroma, stromal fertile portion (SFP) densely covered with numerous ascocarps, and ascospores of natural Cordyceps sinensis. Methods Immature and mature C. sinensis specimens were harvested. Mature C. sinensis specimens were continuously cultivated in our laboratory (altitude 2,200 m). The SFPs (with ascocarps) and ascospores of C. sinensis were collected for microscopic and molecular analyses using species-/genotype-specific primers. Sequences of mutant genotypes of O. sinensis were aligned with that of Genotype #1 Hirsutella sinensis and compared phylogenetically using a Bayesian majority-rule method. Results Fully and semiejected ascospores were collected from the same specimens. The semiejected ascospores tightly adhered to the surface of the asci as observed by the naked eye and under optical and confocal microscopies. The multicellular heterokaryotic ascospores showed uneven staining of nuclei. The immature and mature stromata, SFPs (with ascocarps) and ascospores were found to differentially contain several GC- and AT-biased genotypes of O. sinensis, Samsoniella hepiali, and an AB067719-type fungus. The genotypes within AT-biased Cluster-A in the Bayesian tree occurred in all compartments of C. sinensis, but those within AT-biased Cluster-B were present in immature and mature stromata and SPFs but absent in the ascospores. Genotype #13 of O. sinensis was present in semi-ejected ascospores and Genotype #14 in fully ejected ascospores. GC-biased Genotypes #13–14 featured large DNA segment substitutions and genetic material recombination between the genomes of the parental fungi (H. sinensis and the AB067719-type fungus). These ascosporic offspring genotypes combined with varying abundances of S. hepiali in the 2 types of ascospores participated in the control of the development, maturation and ejection of the ascospores. Conclusion Multiple genotypes of O. sinensis coexist differentially in the stromata, SFPs and 2 types of C. sinensis ascospores, along with S. hepiali and the AB067719-type fungus. The fungal components in different combinations and their dynamic alterations in the compartments of C. sinensis during maturation play symbiotic roles in the lifecycle of natural C. sinensis.

With the rapid development of the high-speed railway in China, the problems of the noise pollution induced by passing trains emerge. Theoretically, the V-shaped noise barrier is of pretty good performance of noise-reduction and load-shedding. To assess the practical aerodynamic deloading characteristics of the V-shaped noise barrier, a full-scale field test was carried out at three measuring-sections equipped with noise barriers of different heights. In order to quantify the research work, the impact strength and deloading rate were selected as indicators. The effects of train speeds, train types and barrier heights are studied. This study includes the variations of impact strength and deloading rate in vertical directions. Meanwhile, 2D numerical simulation research is conducted to analyze the experimental results from the angle of mechanism. It is observed that the aerodynamic load acting on the surface of the V-shaped noise barrier was weaker and more uniform compared with conventional barrier. The flow field distribution influenced the deloading characteristics of the V-shaped noise barrier significantly. Moreover, the load-shedding effect of V-shaped noise barrier, when CRH380AM passed by, was slightly better than CRH380A. The deloading rate improved with the increasing of the noise barrier height in general.

Objective To explore the performance of mobile health platform for standardized management of pregnant women with gestational diabetes mellitus(GDM). Methods A randomized controlled trial was conducted,in which 295 women with GDM were randomized into two groups(traditional management group and mobile health management group)by a computer-generated sequence.The traditional management group accepted standardized GDM management,and the mobile health management group was supplemented by mobile health management based on the standardized management.The glycemic control rate and the incidences of low birth weight,macrosomia,preterm birth,premature rupture of membranes,postpartum hemorrhage after cesarean section,neonatal asphyxia,malformation,and admission to the neonatal intensive care unit were compared between the two groups. Results The glycemic control rate in mobile health management group was significantly higher than that in the traditional management group [(67.22±22.76)%

Herein, a derivate from tanshinone IIA, 1,6,6-trimethyl-11-phenyl-7,8,9,10-tetrahydro-6H-furo[2′,3′:1,2]phenanthro[3,4-d]imidazole (TA25), has been synthesized and investigated as potential inhibitor against the proliferation, migration and invasion of lung cancer cells. MTT assay and cell colony formation assay results showed that TA25 exhibits acceptable inhibitory effect against the proliferation of lung cancer A549 cells, and the value of IC50 was about 17.9 μM. This result was further confirmed by the inhibition of TA25 against the growth of xenograft lung cancer cells on zebrafish bearing tumor (A549 lung cancer cells). The results of wound-healing assay and FITC-gelatin invasion assay displayed that TA25 could inhibit the migration and invasion of lung cancer A549 cells. Moreover, the studies on the binding properties of TA25 interact with c-myc G-quadruplex DNA suggested that TA25 can bind in the G-quarter plane formed from G7, G11, G16 and G20 with c-myc G-quadruplex DNA through π-π stacking. Further study of the potential anti-cancer mechanism indicated that TA25 can induce S-phase arrest in lung cancer A549 cells, and this phenomenon resulted from the promotion of the production of reactive oxygen species and DNA damage in A549 cells under the action of TA25. Further research revealed that TA25 could inhibit the PI3K/Akt/mTOR signal pathway and increase the expression of p53 protein. Overall, TA25 can be developed into a promising inhibitor against the proliferation, migration and invasion of lung cancer cells and has potential clinical application in the near future.

This paper presents a single-phase and three-phase compatible isolated on-board charger for electric vehicles. The charger is compatible with the single-phase and three-phase AC voltage input and is composed of two-stage circuits. Based on the three-phase six-switch power factor correction (PFC) circuit, by switching on and off, the front stage is transformed into a cascade topology of a totem-pole PFC circuit and boost circuit. The rear stage is a full-bridge LLC resonant converter. In the single-phase or three-phase working mode, the front-stage control strategy is a double closed-loop control. The current inner loop controller is improved for the three-phase six-switch PFC circuit. The PI controller and repetitive controller are connected in parallel to form the current inner loop compound controller, which can effectively reduce the total harmonic distortion of the input current. By using simulation software MATLAB/Simulink, the circuit model was built. The simulation results verify the correctness of the theoretical analysis.

Large-scale application of ultrasonic cavitation in chemical engineering is hindered by the energy attenuation along the propagation direction. This paper is devoted to investigating the longitudin...

Cavitation bubble always exists in the droplets breaking up from the fuel jet when supercavitation phenomenon occurs. The collapse of cavitation bubble plays an important role in secondary breakup of droplets. The collapse process of cavitation bubble within the diesel droplet considering the phase change or not have been simulated numerically based on the volume of fluid (VOF) method using OpenFOAM. The results show that collapse process without phase change consists of multiple collapse and rebound stages, similar to the vibration process of a damping spring oscillator. Considering the phase change, there is only collapse stage and no rebound stage in collapse process, and the variation of bubble volume with time is no longer cyclic. The collapse speed become faster with the increasing of environmental pressure, while the collapse speed become faster with the decreasing of saturation vapor pressure. The effect of surrounding pressure on collapse process is greater than the effect of saturation vapor pressure.

Figure S1. (A) PM2.5 and NNK induced lung Bet1A1 and NCI-H23 cell proliferation. (B) Sphere formation of lung cancer stem cells induced by PM2.5 or NNK. (C) CSC tumor sphere assay on PM2.5- or NNK-treated Bet1A and NCI-H23 cells. (D) PM2.5 induced Bet1A and NCI-H23 cell invasion. (E) PM2.5and NNK treatment with 28 days promoted the expression of lung cell carcinogenesis-related biomarkers. Figure S2. (A) 15-LOX1 and 15-LOX2 expression in human lung tumor tissues and non-tumor tissues. (B) The levels of vimentin in 109 paired NSCLC tissues and adjacent normal non-tumor tissues. (C) Vimentin expression in human lung tumor tissues and non-tumor tissues. (D) Restoration of 15-LOX1 and 15-LOX2 activities inhibited the effects of PM2.5 or NNK on the expression of lung carcinogenetic proteins. (E) Restoration of 15-LOX1 and 15-LOX2 activities inhibited the effects of PM2.5 or NNK on cell migration. Figure S3. MassArray design for 15-LOX1 methylation detection. (A) Sequence information of 15-LOX1 methylation design. (B) Prediction of potential CpG islands using http://www.ebi.ac.uk/Tools/seqstats/emboss_cpgplot/ website. (C) Primers design using sequenomÂŽEpiDesigner program. Figure S4. Cloning of 15-LOX1 3'-UTR and 15-LOX2 3'-UTR. Table S1. Baseline demographic characteristics of 109 human NSCLC patients underwent Vimentin analysis. Table S2. Human 15-LOX1 gene methylation level in NCI-H23 and Bet1A cells treated by PM2.5 and NNK. (DOCX 8597 kb)

With growing concerns over air quality in many countries around the world, metal–organic frameworks are now being widely researched for its application in developing air filtration technology for PM2.5 removal. Our study reports the successful fabrication of a polyacrylic acid @zeolitic imidazolate framework-8 (PAA@ZIF-8) membrane using electrospinning technology which shows great promise for PM2.5 filtration. Our PAA@ZIF-8 membrane had a small pore size at 0.5 µm with a porosity of 89.4%, and after modification by ZIF-8, the PAA@ZIF-8 membrane gained porous rough nanofibers, positive surface zeta potential, and high tensile strength. Our tests confirmed the PAA@ZIF-8 membrane’s high potential for PM2.5 filtration over commercial PVDF and electrospun PAA membranes, recording a PM2.5 retention rate of 99.6%. Besides its small pore size, the PAA@ZIF-8 membrane’s rough and porous nanofiber structure created a high BET surface area (344.9 m2/g) which physically adsorbs the PM2.5 particles. Additionally, we found that the positive surface zeta potential (67.3 mV at PH = 7) of the ZIF-8-coated nanofibers attracts negatively charged PM2.5 particles combined in air moisture, thereby further improving the PM2.5 filtration rate.

A series of Mn/TiWOx catalysts were prepared and used in NH3-SCR reaction for NOx emission control. The experimental results showed that the SCR activities of Mn/TiWOx catalysts are higher than that of Mn/TiO2 catalyst. After that, several characterization techniques including XRD, H2-TPR, NH3-TPD, XPS were used to investigate the effect of TiWOx support on the SCR performance of Mn/TiWOx (1:1) catalyst. The stronger reducibility and NH3 adsorption capacity, and more surface chemisorbed oxygen of Mn/TiWOx (1:1) should all contribute to its better SCR performance. Moreover, Mn/TiWOx (1:1) catalyst shows higher N2 selectivity, better SO2 tolerance and stability than Mn/TiO2 catalyst. The results of in situ DRIFT study revealed that the NH3-SCR reactions over Mn/TiO2 and Mn/TiWOx (1:1) were all followed the Langmuir–Hinshelwood mechanism, in which the SCR reaction takes place between the adsorbed NH3 species and NOx species.

The effect of HF treatment on the performance of ceria for selective catalytic reduction of NO with NH3 was investigated in this study. The experimental results showed that HF treatment could greatly enhance the SCR performance of ceria within the temperature range of 100–400 °C. From the characterization results of Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD), temperature programmed reduction of hydrogen (H2-TPR), temperature programmed desorption of ammonia (NH3-TPD) and X-ray photoelectron spectroscopy (XPS), the good performance of HF-treated ceria may be attributed to its lower crystallinity, better reducibility, higher NH3 adsorption capacity, and the enrichment of surface chemisorbed oxygen. And the results of in situ DRIFT study indicate that the NH3-SCR reactions on CeO2 and CeO2-F mainly follow the Eley–Rideal mechanism.

In this study, it was found that the doping of Co on Mn/TiO 2 catalyst could enhance its K resistance. The characterization results showed that the modification of Mn/TiO 2 catalyst by Co could increase its reducibility and the adsorption of NH 3 and NO x species on it. From the results of in situ DRIFT study, the NH 3 -SCR reaction over Mn/TiO 2 catalyst obeyed the Langmuir–Hinshelwood mechanism. And the addition of K on Mn–Co/TiO 2 had little inhibition effect on NO x adsorption. These features made Mn–Co/TiO 2 catalyst show better K resistance than Mn/TiO 2 .

Na has a serious deactivation effect on Mn/TiO2 catalyst for selective catalytic reduction of NO with NH3. In this study, it was found that Sb had a promotion effect on the Na resistance of MnOx/TiO2 catalyst. Then the promotion mechanism was investigated based on the characterization results of BET, XRD, H2-TPR, NH3-TPD, XPS and in situ DRIFT. The results of H2-TPR and NH3-TPD showed that the addition of Sb on MnOx/TiO2 could enhance the redox ability and surface acidity respectively, and the results of DRIFT indicated that the addition of Sb on MnOx/TiO2 could generate strong Lewis acid sites on the catalyst surface for NH3 adsorption. Therefore, the doping of Sb has a promotion effect on the Na resistance of Mn/TiO2 catalyst.

The deactivation mechanism of phosphorous on a Mn/TiO2 catalyst for selective catalytic reduction of NO with NH3 was investigated in this study. It was found that the NH3-SCR reaction over the Mn/TiO2 catalyst obeyed the Langmuir–Hinshelwood mechanism. From the characterization results, it could be found the addition of phosphorous on the Mn/TiO2 catalyst would decrease its reducibility and inhibit the adsorption of chemisorbed oxygen and NOx species on its surface. As a result, the P-doped Mn/TiO2 catalyst was deactivated.

Heavy metals have been proven to be of deactivation effect on SCR catalyst. In this paper, the poisoning effect of heavy metals (Zn and Pb) on Mn/TiO 2 catalyst was investigated based on experimental and theoretical study. It was found that both of Zn and Pb had a poisoning effect on Mn/TiO 2 catalyst and the poisoning effect of Zn was more obvious. The characterization results indicated that the doping of heavy metals on Mn/TiO 2 surface would lead to a great decrease of reducibility, surface acidity and NO adsorption ability. The results of XPS characterization revealed the decrease of Mn 4+ atomic concentration and chemisorbed oxygen species caused by the doping of heavy metals. Based on the above mentioned unfavorable properties, the doping of heavy metals would cause a serious deactivation of Mn/TiO 2 catalyst. From the results of DFT calculations, it could be concluded that the doping of heavy metals on Mn/TiO 2 catalyst resulting in a great decrease of NH 3 adsorption capacity and NO adsorption ability, which agrees well with the experimental results.

Ce/TiO 2 is a prospective catalyst used for low temperature selective catalytic reduction (SCR) of NO with NH 3 . In this paper, the poisoning effect of Zn and Pb on the SCR performance of Ce/TiO 2 catalyst was investigated. Experimental results indicated that both Zn and Pb had a poisoning effect on Ce/TiO 2 catalyst, and Pb exhibited more poisoning effect than Zn in most of the reaction temperature range. Combined with the characterization results, we proposed that the enlargement of TiO 2 nanoparticles, the reduced chemisorbed oxygen content and surface acidity all contribute to the deactivation of Zn–Ce/TiO 2 and Pb–Ce/TiO 2 .

The skid-steering vehicle is able to be steered by the speed difference of the inside and outside wheels created by controlling the torque distribution of all drive wheels. The three degree of freedom dynamic equations are established for electric ground vehicle with six in-wheeled motors, based on which the drag force calculation model is presented under steady skid-steering condition. Then the variation of resistance torque with the steer input and vehicle velocity is analyzed including its theoretic constraint limit. The steering resistance moment of the electric ground vehicle is compared with that of the tracked vehicle with the same vehicle parameters. In order to validate the calculation results, the virtual prototype model is created and the dynamic simulation is executed in ADAMS software. The results indicate that the resistance moment of electric ground vehicle is more than that of the tracked vehicle with same configurations and the computational model is correct.

INTRODUCTION The Saccharomyces cerevisiae 2.0 project (Sc2.0) aims to modify the yeast genome with a series of densely spaced designer changes. Both a synthetic yeast chromosome arm (synIXR) and the entirely synthetic chromosome (synIII) function with high fitness in yeast. For designer genome synthesis projects, precise engineering of the physical sequence to match the specified design is important for the systematic evaluation of underlying design principles. Yeast can maintain nuclear chromosomes as rings, occurring by chance at repeated sequences, although the cyclized format is unfavorable in meiosis given the possibility of dicentric chromosome formation from meiotic recombination. Here, we describe the de novo synthesis of synthetic yeast chromosome V (synV) in the “Build-A-Genome China” course, perfectly matching the designer sequence and bearing loxPsym sites, distinguishable watermarks, and all the other features of the synthetic genome. We generated a ring synV derivative with user-specified cyclization coordinates and characterized its performance in mitosis and meiosis. RATIONALE Systematic evaluation of underlying Sc2.0 design principles requires that the final assembled synthetic genome perfectly match the designed sequence. Given the size of yeast chromosomes, synthetic chromosome construction is performed iteratively, and new mutations and unpredictable events may occur during synthesis; even a very small number of unintentional nucleotide changes across the genome could have substantial effects on phenotype. Therefore, precisely matching the physical sequence to the designed sequence is crucial for verification of the design principles in genome synthesis. Ring chromosomes can extend those design principles to provide a model for genomic rearrangement, ring chromosome evolution, and human ring chromosome disorders. RESULTS We chemically synthesized, assembled, and incorporated designer chromosome synV (536,024 base pairs) of S. cerevisiae according to Sc2.0 principles, based on the complete nucleotide sequence of native yeast chromosome V (576,874 base pairs). This work was performed as part of the “Build-A-Genome China” course in Tianjin University. We corrected all mutations found—including duplications, substitutions, and indels—in the initial synV strain by using integrative cotransformation of the precise desired changes and by means of a clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9)–based method. Altogether, 3331 corrected base pairs were required to match to the designed sequence. We generated a strain that exactly matches all designer sequence changes that displays high fitness under a variety of culture conditions. All corrections were verified with whole-genome sequencing; RNA sequencing revealed only minor changes in gene expression—most notably, decreases in expression of genes relocated near synthetic telomeres as a result of design. We constructed a functional circular synV (ring_synV) derivative in yeast by precisely joining both chromosome ends (telomeres) at specified coordinates. The ring chromosome showed restoration of subtelomeric gene expression levels. The ring_synV strain exhibited fitness comparable with that of the linear synV strain, revealed no change in sporulation frequency, but notably reduced spore viability. In meiosis, heterozygous or homozygous diploid ring_wtV and ring_synV chromosomes behaved similarly, exhibiting substantially higher frequency of the formation of zero-spore tetrads, a type that was not seen in the rod chromosome diploids. Rod synV chromosomes went through meiosis with high spore viability, despite no effort having been made to preserve meiotic competency in the design of synV. CONCLUSION The perfect designer-matched synthetic chromosome V provides strategies to edit sequence variants and correct unpredictable events, such as off-target integration of extra copies of synthetic DNA elsewhere in the genome. We also constructed a ring synthetic chromosome derivative and evaluated its fitness and stability in yeast. Both synV and synVI can be circularized and can power yeast cell growth without affecting fitness when gene content is maintained. These fitness and stability phenotypes of the ring synthetic chromosome in yeast provide a model system with which to probe the mechanism of human ring chromosome disorders. Synthesis, cyclization, and characterization of synV . ( A ) Synthetic chromosome V (synV, 536,024 base pairs) was designed in silico from native chromosome V (wtV, 576,874 base pairs), with extensive genotype modification designed to be phenotypically neutral. ( B ) CRISPR/Cas9 strategy for multiplex repair. ( C ) Colonies of wtV, synV, and ring_synV strains.

Mn/TiO2 catalyst is of high activity for low temperature selective catalytic reduction (SCR) of NO with NH3. And the deposition of alkali metal would lead to the deactivation of Mn/TiO2 catalyst. In this paper, the poisoning effect of Na and K on Mn/TiO2 was investigated based on experimental and theoretical study. It was found that K had a stronger poisoning effect than that of Na. The bad performance of K–Mn/TiO2 may be due to its small surface area, high crystallinity, weak surface acidity, low content of Mn4+ and chemisorbed oxygen, and bad redox ability. The interpretation of the experimental results is supported by DFT calculations.

Objective: The goal of this study was to develop and validate density-weighted arithmetic methods for the analysis of the dynamic maturational changes in random amplified polymorphic DNA (RAPD) polymorphisms in Cordyceps sinensis containing multiple fungi. Methods: Ten random primers were used for PCR amplification to monitor changes in the RAPD molecular marker polymorphisms in caterpillar body, stroma and ascocarp portion samples of C. sinensis collected at different stages of maturation. We compared (1) the density-unweighted Nei-Li similarity equation and new similarity equations considering the densities of DNA bands and (2) the density-unweighted and weighted arithmetic methods for cluster analysis. Results: The algorithm using the Nei-Li similarity equation did not account for the differences in the density of the matched randomly amplified amplicons, whereas the new similarity equations were capable of integrating different amplicon densities into the similarity computation. With improvements in the similarity computation and cluster construction, the new methods revealed dynamic maturational changes in the RAPD polymorphisms of molecular markers in C. sinensis caterpillar bodies and stromata. The polymorphism analysis revealed similarities of 74%-88% between the RAPD polymorphisms of the ascocarp portion versus premature and mature C. sinensis stromata, but low similarities of

Hybrid perovskites are a series of solution-processable materials for photovoltaic devices. To achieve better performance and stability, interface passivation is an effective method. So far, the most commonly used passivators are organic amines, which can tailor perovskite into a lower-dimensional structure (Ruddlesden-Popper perovskite). Here, we select a biimizole (BIM) molecule as a new passivator for perovskite. The BIM based single layer perovskite has a more rigid structure. And multi-layered structure cannot be formed due to large lattice mismatching and structural rigidity. By inducing the excess MAI (methanaminium iodide) into the lattice, the layered structure is maintained, and half of the BIM molecules are replaced by MA (methylamine). The mixed layered structure is distorted, because of the difference in size between two kinds of cations. We then investigate passivation effect of BIM on perovskite solar cells. By carefully controlling the feed ratio in precursor solutions, we fabricate solar cells with different passivation structures. We find that the introduction of BIM can cause Voc to increase generally, indicating that MAPbI3 is well passivated. The peak at 7.5° and 15° in X-ray diffraction pattern are corresponding to a two-dimensional (2D) phase with a shorter layer distance. There are no peaks at lower degrees, so that no multi-layered structure is formed in the film either. We suppose that a dual-phase 2D-3D (where 3D represents three-dimensional) structure is formed in the perovskite film. To explain the passivation effect of the two 2D structures, we investigate their lattice matching towards MAPbI3. The distorted 2D structure is well matched with (110) face of o-MAPbI3, and the mismatching rate is lower 1% in the two directions. On the other hand, the BIM based 2D structure cannot well match with (–110) face of o-MAPbI3, nor with (001) face of c-MAPbI3. We also consider that the less rigidity of distorted structure contributes to better passivation. As a result, we achieve a BIM passivated perovskite solar cell with a power conversion efficiency up to 14%. This work paves a new way to the interface engineering of perovskite solar cells.

The corrugated pipe is widely used in figure heat exchangers. For the reason of large temperature difference between the gas in the pipe and the cold wall, particles may deposit on the wall, and make some adverse effects, such as poor cooling effect and the block in the pipe, especially in the pipe node. To solve the problem of deposition in the pipe, this paper will apply the model of DRW to calculate the trajectory of the micro particles. In this paper, the trajectories of particles with different sizes in a corrugated pipe are calculated, and the effects of structure parameter and inlet velocity on the trajectories of particles are studied. The conclusion can provide a theoretical basis for solving the deposition in corrugated pipes.

Seronegative hepatitis—non-A, non-B, non-C, non-D, non-E hepatitis—is poorly characterized but strongly associated with serious complications. We collected 92 sera specimens from patients with non-A–E hepatitis in Chongqing, China between 1999 and 2007. Ten sera pools were screened by Solexa deep sequencing. We discovered a 3,780-bp contig present in all 10 pools that yielded BLASTx E scores of 7e-05–0.008 against parvoviruses. The complete sequence of the in silico -assembled 3,780-bp contig was confirmed by gene amplification of overlapping regions over almost the entire genome, and the virus was provisionally designated NIH-CQV. Further analysis revealed that the contig was composed of two major ORFs. By protein BLAST, ORF1 and ORF2 were most homologous to the replication-associated protein of bat circovirus and the capsid protein of porcine parvovirus, respectively. Phylogenetic analysis indicated that NIH-CQV is located at the interface of Parvoviridae and Circoviridae . Prevalence of NIH-CQV in patients was determined by quantitative PCR. Sixty-three of 90 patient samples (70%) were positive, but all those from 45 healthy controls were negative. Average virus titer in the patient specimens was 1.05 e4 copies/µL. Specific antibodies against NIH-CQV were sought by immunoblotting. Eighty-four percent of patients were positive for IgG, and 31% were positive for IgM; in contrast, 78% of healthy controls were positive for IgG, but all were negative for IgM. Although more work is needed to determine the etiologic role of NIH-CQV in human disease, our data indicate that a parvovirus-like virus is highly prevalent in a cohort of patients with non-A–E hepatitis.

In order to achieve MTFs at different contrasts, the MTF measurement system is designed and developed. Two integrating spheres are used to illuminate the face and back of the test target uniformly. The target luminance and background luminance of the test target are regulated by adjusting the attenuators near the entrance of each integrating sphere. The many groups’ experimental results indicate that the luminance differences between the values by the system and those by L88 first level luminance meter, which is checked by National Institute of Metrology P. R. China, are within ±0.3 cd/m2. Thereby the measurement precision can be ensured in MTF test. MTFs of Sony camera and Cannon camera at different contrasts are measured by this system. The measurement values show that MTFs at different contrasts can demonstrate the imaging quality fully and objectively. This study provides an effective method to evaluate the imaging quality of visible imaging systems.

The nervous and vascular systems, although functionally different, share many common regulators of function maintenance. Long non‐coding RNAs (lncRNAs) are important players in many biological processes and human disorders. We previously identified a role of MALAT1 in microvascular dysfunction. However, its role in neurodegeneration is still unknown. Here, we used the eye as the model to investigate the role of MALAT1 in retinal neurodegeneration. We show that MALAT1 expression is significantly up‐regulated in the retinas, Muller cells, and primary retinal ganglion cells (RGCs) upon stress. MALAT1 knockdown reduces reactive gliosis, Muller cell activation, and RGC survival in vivo and in vitro . MALAT1‐CREB binding maintains CREB phosphorylation by inhibiting PP2A‐mediated dephosphorylation, which leads to continuous CREB signaling activation. Clinical and animal experimentation suggests that MALAT1 dysfunction is implicated in neurodegenerative processes and several human disorders. Collectively, this study reveals that MALAT1 might regulate the development of retinal neurodegeneration through CREB signaling.

Vascular remodeling is an important pathological feature of hypertension, leading to increased vascular resistance and reduced compliance. Endothelial cell (EC) and vascular smooth muscle cell (VSMC) dysfunction is involved in vascular remodeling. Long noncoding RNAs are potential regulators of EC and VSMC function. Herein, we determined whether long noncoding RNA–growth arrest–specific 5 (GAS5) is involved in hypertension-related vascular remodeling. We revealed that GAS5 knockdown aggravated hypertension-induced microvascular dysfunction as shown by increased retinal neovascularization and capillary leakage. GAS5 regulated the remodeling of arteries, including caudal arteries, carotid arteries, renal arteries, and thoracic arteries. GAS5 was mainly expressed in ECs and VSMCs, and its expression was significantly downregulated in hypertension. GAS5 knockdown affected endothelial activation, endothelial proliferation, VSMC phenotypic conversion, and EC-VSMC communication in vivo and in vitro. Mechanistically, GAS5 regulated EC and VSMC function through β-catenin signaling. This study identified GAS5 as a critical regulator in hypertension and demonstrated the potential of gene therapy and drug development for treating hypertension.

In order to improve the dynamic performance of five-axis heavy vehicle, a variable universe fuzzy control method is proposed to optimize suspension parameters. Five-axis multi-body dynamic model including electro-hydraulic proportional valve was firstly established in software ADAMS/Car. The variable universe fuzzy controller based on fuzzy neural network was also designed in MATLAB/Simulink, and then the co-simulation was conducted. The dynamic characteristics of five-axis heavy vehicle are studied to verify the effect of suspension parameters optimized by variable universe fuzzy control method in the A, B and C-level random pavement and different speed conditions. Simulation results show that compared with passive suspension, the real-time optimization of variable fuzzy control based on FNN can improve the ride comfort and the dynamic load of tire. Under different driving conditions, ride comfort can be increased by about 25%-30%, and the dynamic load of tire generally decreases by 25%-35%. Therefore this method has a certain practicability and effectiveness.

Human parvovirus 4 (PARV4) is an emerging human virus, and little is known about the molecular aspects of PARV4 apart from its incomplete genome sequence, which lacks information of the termini. We analyzed the gene expression profile of PARV4 using a nearly full-length HPV4 genome in a replication competent system in 293 cells. We found that PARV4 utilizes two promoters to transcribe non-structural protein- and structural protein-encoding mRNAs, respectively, which were polyadenylated at the right end of the genome. Three major proteins, including the large non-structural protein NS1a, whose mRNA is spliced, and capsid proteins VP1 and VP2, were detected. Additional functional analysis of the NS1a revealed its capability to induce cell cycle arrest at G2/M phase in ex vivo-generated human hematopoietic stem cells. Taken together, our characterization of the molecular features of PARV4 suggests that PARV4 represents a new genus in the family Parvoviridae.

Human parvovirus B19 (B19V) is the only human pathogenic parvovirus. It causes a wide spectrum of human diseases, including fifth disease (erythema infectiosum) in children and pure red cell aplasia in immunocompromised patients. B19V is highly erythrotropic and preferentially replicates in erythroid progenitor cells (EPCs). Current understanding of how B19V interacts with cellular factors to regulate disease progression is limited, due to a lack of permissive cell lines and animal models. Here, we employed a recently developed primary human CD36(+) EPC culture system that is highly permissive for B19V infection to identify cellular factors that lead to cell cycle arrest after B19V infection. We found that B19V exploited the E2F family of transcription factors by downregulating activating E2Fs (E2F1 to E2F3a) and upregulating repressive E2Fs (E2F4 to E2F8) in the primary CD36(+) EPCs. B19V nonstructural protein 1 (NS1) was a key viral factor responsible for altering E2F1-E2F5 expression, but not E2F6-E2F8 expression. Interaction between NS1 and E2F4 or E2F5 enhanced the nuclear import of these repressive E2Fs and induced stable G₂ arrest. NS1-induced G₂ arrest was independent of p53 activation and increased viral replication. Downstream E2F4/E2F5 targets, which are potentially involved in the progression from G₂ into M phase and erythroid differentiation, were identified by microarray analysis. These findings provide new insight into the molecular pathogenesis of B19V in highly permissive erythroid progenitors.

The pre-mRNA processing strategy of the B19 virus is unique among parvoviruses. B19 virus-generated pre-mRNAs are transcribed from a single promoter and are extensively processed by alternative splicing and alternative polyadenylation to generate 12 transcripts. Blockage of the production of full-length B19 virus transcripts at the internal polyadenylation site [(pA)p] was previously reported to be a limiting step in B19 virus permissiveness. We show here that in the absence of genome replication, internal polyadenylation of B19 virus RNAs at (pA)p is favored in cells which are both permissive and nonpermissive for B19 viral replication. Replication of the B19 virus genome, however, introduced either by viral infection or by transfection of an infectious clone into permissive cells or forced by heterologous replication systems in nonpermissive cells, enhanced readthrough of (pA)p and the polyadenylation of B19 virus transcripts at the distal site [(pA)d]. Therefore, replication of the genome facilitates the generation of sufficient full-length transcripts that encode the viral capsid proteins and the essential 11-kDa nonstructural protein. Furthermore, we show that polyadenylation of B19 viral RNA at (pA)p likely competes with splicing at the second intron. Thus, we conclude that replication of the B19 virus genome is the primary limiting step governing B19 virus tropism.

Three full-length genomic clones (pB19-M20, pB19-FL and pB19-HG1) of parvovirus B19 were produced in different laboratories. pB19-M20 was shown to produce infectious virus. To determine the differences in infectivity, all three plasmids were tested by transfection and infection assays. All three clones were similar in viral DNA replication, RNA transcription, and viral capsid protein production. However, only pB19-M20 and pB19-HG1 produced infectious virus. Comparison of viral sequences showed no significant differences in ITR or NS regions. In the capsid region, there was a nucleotide sequence difference conferring an amino acid substitution (E176K) in the phospholipase A2-like motif of the VP1-unique (VP1u) region. The recombinant VP1u with the E176K mutation had no catalytic activity as compared with the wild-type. When this mutation was introduced into pB19-M20, infectivity was significantly attenuated, confirming the critical role of this motif. Investigation of the original serum from which pB19-FL was cloned confirmed that the phospholipase mutation was present in the native B19 virus.

The pathogenic parvovirus B19 (B19V) has an extreme tropism for human erythroid progenitor cells. In vitro, only a few erythroid leukemic cell lines (JK-1 and KU812Ep6) or megakaryoblastoid cell lines (UT7/Epo and UT7/Epo-S1) with erythroid characteristics support B19V replication, but these cells are only semipermissive. By using recent advances in generating large numbers of human erythroid progenitor cells (EPCs) ex vivo from hematopoietic stem cells (HSCs), we produced a pure population of CD36 + EPCs expanded and differentiated from CD34 + HSCs and assessed the CD36 + EPCs for their permissiveness to B19V infection. Over more than 3 weeks, cells grown in serum-free medium expanded more than 800,000-fold, and 87 to 96% of the CD36 + EPCs were positive for globoside, the cellular receptor for B19V. Immunofluorescence (IF) staining showed that about 77% of the CD36 + EPCs were positive for B19V infection, while about 9% of UT7/Epo-S1 cells were B19V positive. Viral DNA detected by real-time PCR increased by more than 3 logs in CD36 + EPCs; the increase was 1 log in UT7/Epo-S1 cells. Due to the extensive permissivity of CD36 + EPCs, we significantly improved the sensitivity of detection of infectious B19V by real-time reverse transcription-PCR and IF staining 100- and 1,000-fold, respectively, which is greater than the sensitivity of UT7/Epo-S1 cell-based methods. This is the first description of an ex vivo method to produce large numbers of EPCs that are highly permissive to B19V infection and replication, offering a cellular system that mimics in vivo infection with this pathogenic human virus.

In an attempt to experimentally define the roles of viral proteins encoded by the B19 genome in the viral life cycle, we utilized the B19 infectious clone constructed in our previous study to create two groups of B19 mutant genomes: (i) null mutants, in which either a translational initiation codon for each of these viral genes was substituted by a translational termination codon or a termination codon was inserted into the open reading frame by a frameshift; and (ii) a deletion mutant, in which half of the hairpin sequence was deleted at both the 5′ and the 3′ termini. The impact of these mutations on viral infectivity, DNA replication, capsid protein production, and distribution was systematically examined. Null mutants of the NS and VP1 proteins or deletion of the terminal hairpin sequence completely abolished the viral infectivity, whereas blocking expression of the 7.5-kDa protein or the putative protein X had no effect on infectivity in vitro. Blocking expression of the proline-rich 11-kDa protein significantly reduced B19 viral infectivity, and protein studies suggested that the expression of the 11-kDa protein was critical for VP2 capsid production and trafficking in infected cells. These findings suggest a previously unrecognized role for the 11-kDa protein, and together the results enhance our understanding of the key features of the B19 viral genome and proteins.