Selenocysteine methyltransferase SMT catalyzed the synthesis of Se-methylselenocysteine to regulate the accumulation of glucosinolates and sulforaphane in broccoli

Selenocysteine methyltransferase(SMT)is a key enzyme involved in the Se metabolism pathway,and it is responsible for the catalysis of Se-methylselenocysteine(SeMSC)compound formation.Previous studies showed that selenium treatment activated SMT expression and promoted the accumulation of glucosinolates(GSLs)and sulforaphane,but the roles and functional mechanisms of SMT in mediating GSLs and sulforaphane synthesis remain unclear.In this study,we identified the BoSMT gene in broccoli and uncovered its roles in mediating GSLs biosynthesis.Transgenic assays revealed that BoSMT is involved in SeMSC biosynthesis in broccoli.More importantly,the contents of GSLs and sulforaphane were significantly increased in the BoSMT-overexpressing broccoli lines but decreased in the knockdown lines,suggesting that BoSMT played a positive role in regulating GSLs and sulforaphane synthesis.Further evidence indicated that BoSMT-mediated overaccumulation of GSLs and sulforaphane might be due to the increase in the endogenous SeMSC content.Compared with the mock(water)treatment,selenite-induced significantly increases of the SeMSC content in the BoSMT-knockdown plants partially compensated the phenotype of GSLs and sulforaphane loss.Compared with the mock treatment,exogenous SeMSC treatment significantly increased the contents of GSL and sulforaphane and activated GSL synthesis-related gene expression,suggesting that SeMSC acted as a positive regulator for GSL and sulforaphane production.Our findings provided novel insights into selenium-mediated GSLs and sulforaphane accumulation.The genetic manipulation of BoSMT might be a useful strategy for improving the dietary nutritional values of broccoli.

BoMyrosinase plays an essential role in sulforaphane accumulation in response to selenite treatment in broccoli

Sulforaphane, a naturally specialized metabolite, plays significant roles in human disease prevention and plant defense. Myrosinase(MY) is a key gene responsible for the catalysis of sulforaphane formation, but the molecular mechanisms through which MY regulates sulforaphane biosynthesis in plants remains largely unknown. Here, we discovered that the change of sulforaphane content in broccoli sprouts caused by exogenous selenite treatments is positively related to BoMY expression. BoMY overexpression in the Arabidopsis thaliana tgg1 mutants could dramatically increase myrosinase activity and sulforaphane content in the rosette leaves of 35S::BoMY/tgg1 and rescue its phenotypes.Moreover, an obvious increase of myrosinase activity and sulforaphane content was displayed in transgenic BoMY-overexpressed broccoli lines.In addition, a 2 033 bp promoter fragment of BoMY was isolated. Yeast one-hybrid(Y1H) library screening experiment uncovered that one bHLH transcription factor, BoFAMA, could directly bind to BoMY promoter to activate its expression, which was further evidenced by Y1H assay and dual-luciferase reporter assay. BoFAMA is a selenite-responsive transcription factor that is highly expressed in broccoli leaves;its protein is solely localized to nucleus. Additionally, genetic evidence suggested that the knockdown of FAMA gene in Arabidopsis thaliana could significantly decrease sulforaphane yield by inhibiting the expression of myrosinase genes. Interestingly, exogenous selenite supply could partially restore the low level of sulforaphane content in transgenic Arabidopsis FAMA-silencing plants. Our findings uncover a novel function of FAMAMY module in the regulation of selenite-mediated sulforaphane synthesis and provide a new insights into the molecular mechanism by which selenite regulates the accumulation of sulforaphane in plants.

Synergistic Optimization of Buried Interface by Multifunctional Organic-Inorganic Complexes for Highly Efficient Planar Perovskite Solar Cells

For the further improvement of the power conversion efficiency(PCE)and stability of perovskite solar cells(PSCs),the buried interface between the perovskite and the electron transport layer is crucial.However,it is challenging to effectively optimize this interface as it is buried beneath the perovskite film.Herein,we have designed and synthesized a series of multifunctional organic-inorganic(OI)complexes as buried interfacial material to promote electron extraction,as well as the crystal growth of the perovskite.The OI complex with BF4−group not only eliminates oxygen vacancies on the SnO_(2) surface but also balances energy level alignment between SnO_(2) and perovskite,providing a favorable environment for charge carrier extraction.Moreover,OI complex with amine(−NH_(2))functional group can regulate the crystallization of the perovskite film via interaction with PbI2,resulting in highly crystallized perovskite film with large grains and low defect density.Consequently,with rational molecular design,the PSCs with optimal OI complex buried interface layer which contains both BF4−and−NH_(2) functional groups yield a champion device efficiency of 23.69%.More importantly,the resulting unencapsulated device performs excellent ambient stability,maintaining over 90%of its initial efficiency after 2000 h storage,and excellent light stability of 91.5%remaining PCE in the maximum power point tracking measurement(under continuous 100 mW cm−2 light illumination in N2 atmosphere)after 500 h.

Upregulation of histone H3 caused by CRYAA may contribute to the development of age-related cataract

Objective:Age-relate cataract(ARC)is a disease of the eyes with no effective drugs to prevent or treat patients.The aim of the present study is to determine whether histone H3,αA-crystallin(CRYAA),β-galactosidase(GLB1),and p53 are involved in the pathogenesis of ARC.Methods:A total of 99 anterior lens capsules(ALCs)of patients with ARC of various nuclear grades,ultraviolet models of ALCs,and two human lens epithelial cell lines(FHL-124 and SRA01/04)were used,and the expression of histone H3,CRYAA,GLB1,and p53 were detected by immunoblotting and reverse transcription and real time-quantitative polymerase chain reaction.The association between CRYAA with histone H3,GLB1,and p53 was assessed in FHL-124 and SRA01/04 cells following CRYAA overexpression.Results:Histone H3 and p53 in ALCs of patients with ARC were up-regulated in a grade-dependent manner,and the expression of CRYAA showed a positive association with histone H3,p53,and GLB1.In UV models of ALCs and human lens epithelial cell lines,the expression levels of histone H3,cell apoptosis factors(Bax/Bcl-2,cleaved caspase-3),and inflammation factors(interleukin-6,tumor necrosis factor-α)were all up-regulated.Furthermore,transfection of CRYAA in FHL-124 cells induced overexpression of histone H3.Conclusion:CRYAA-mediated upregulation of histone H3 may be involved in the pathogenesis of ARC.p53 may also have a role in ARC development,but not via the CRYAA-histone H3 axis.The results of the present study may assist in improving our understanding of the pathogenesis of ARC and in identifying potential targets for treatment.

Request pattern change-based cache pollution attack detection and defense in edge computing

Through caching popular contents at the network edge,wireless edge caching can greatly reduce both the content request latency at mobile devices and the traffic burden at the core network.However,popularity-based caching strategies are vulnerable to Cache Pollution Attacks(CPAs)due to the weak security protection at both edge nodes and mobile devices.In CPAs,through initiating a large number of requests for unpopular contents,malicious users can pollute the edge caching space and degrade the caching efficiency.This paper firstly integrates the dynamic nature of content request and mobile devices into the edge caching framework,and introduces an eavesdroppingbased CPA strategy.Then,an edge caching mechanism,which contains a Request Pattern Change-based Cache Pollution Detection(RPC2PD)algorithm and an Attack-aware Cache Defense(ACD)algorithm,is proposed to defend against CPAs.Simulation results show that the proposed mechanism could effectively suppress the effects of CPAs on the caching performance and improve the cache hit ratio.

Building a Cloud-Based Energy Storage System through Digital Transformation of Distributed Backup Battery in Mobile Base Stations

Battery energy storage systems(ESS) have been widely used in mobile base stations(BS) as the main backup power source. Due to the large number of base stations, massive distributed ESSs have largely stayed in idle and very difficult to achieve high asset utilization. In recent years, the fast-paced development of digital energy storage(DES) technology has revolutionized the traditional operation and maintenance of ESSs by transforming them into digital assets, further enabling battery energy storage services, raising up a new way to achieve a much higher utilization of such kind of largely idle ESS resources. In this paper, the disruptive DES technology will be introduced and its application under the context of mobile BSs will be studied, and then a cloud-based energy storage(CES) platform is proposed based on a large scale distributed DESs to provide a new cyber-enabled energy storage service to the local utility company. A real-world case study shows the effectiveness and efficiency of the CES platform.

CO_2 hydrogenation to methanol over Cu/Zn/Al/Zr catalysts prepared by liquid reduction

Cu/Zn/Al/Zr catalysts containing Cu in three valence states(Cu2+,Cu+and Cu0)were prepared usinga liquid reduction method and subsequently calcined at different temperatures.The effects of thecalcination temperature on the catalyst structure,interactions among components,reducibility anddispersion of Cu species,surface properties and exposed Cu surface area were systematically investigated.These materials were also applied to the synthesis of methanol via the hydrogenation ofCO2.The results show that a large exposed Cu surface area promotes catalytic CO2conversion andthat there is a close correlation between the Cu+/Cu0ratio and the selectivity for methanol.A calcinationtemperature of573K was found to produce a Cu/Zn/Al/Zr catalyst exhibiting the maximumactivity during the synthesis of methanol.

Propane Aromatization over Mo/HZSM-5 Catalysts

Impregnation, mechanical mixing and hydrothermal treatment methods were used to introduce molybdenum species into the HZSM-5 zeolite. The structure and surface acidity of the catalysts were studied by means of XRD, FT-IR, NH3-TPD, TPR and XPS. The effects of Mo content and reaction time on stream on the aromatization of propane were investigated. It was found that the performance of the Mo/HZSM-5 catalyst prepared by the hydrothermal treatment method was much better than that of the other two catalysts. For example, under the reaction conditions of 823 K and 600 h-1, propane conversion and aromatics selectivity over the catalyst prepared by hydrothermal pretreatment could reach 89.17% and 78.56%, respectively. XRD and XPS results showed that the Mo species in the catalysts prepared by hydrothermal treatment were highly dispersed on the surface of the HZSM-5, and larger amounts of them could penetrate into the HZSM-5 channel, as compared with the other two kinds of catalysts. These factors may be responsible for their high activities for propane aromatization. IR and NH3-TPD studies indicated that the number of Bronsted acid centers decreased and the Lewis acid centers increased after Mo was introduced into the HZSM-5 zeolite.

地方师范院校国家一流化学专业建设探索与实践——以安庆师范大学化学专业为例

中国高等教育进入发展的新时代,地方师范院校的专业建设在“双万计划”的实施下迎来了发展的大好机遇。以安庆师范大学化学专业为例,经过40多年的办学,专业定位、师资队伍、教学资源、教学改革、实践教学以及质量监控等专业内涵建设成效明显。站在国家一流专业建设的新起点,笔者从建设一流课程、实施协同育人、优化师资结构以及建立外部评价四个方面着手,就国家一流专业建设进行了初步探讨。

Development of an indirect immunofluorescence assay for PCV3 antibody detection based on capsid protein

Porcine circovirus type 3(PCV3)is a novel porcine circovirus associated with porcine dermatitis and nephritis syndrome(PDNS),reproductive failure,and multisystemic inflammation.Capsid protein(Cap)encoded by PCV3 ORF2 gene has been identified as an immunogenic protein.Currently,there is no immunofluorescence assay(IFA)available for serological diagnosis.Here,the N-terminal 33 amino acids of Cap protein were predicted to serve as a PCV3 nuclear localization signal(NLS).Two types of recombinant plasmids were constructed for recombinant protein expression in 5f9 cells by using a baculovirus expression system:plasmid rvBac-Pc for full-length Cap protein expression and rvBac-Sc for Cap protein expression with a honeybee melittin signal peptide in place of the predicted NLS sequence.Expression of the nuclear localization sequences was further analyzed by IFA.Strong and specific fluorescence signals were observed in the nucleus of rvBac-Pc-transfected cells and in the cytoplasm of rvBac-Sc-transfected cells.No cross-reactivity was observed with porcine circovirus type 2,porcine pseudorabies virus,classical swine fever virus,or porcine reproductive and respiratory syndrome virus.In summary,we developed two fluorescence detection modes for Cap protein that can be used to detect PCV3 antibodies.This method is suitable for the diagnosis and epidemiological investigation of PCV3.This study provides a reliable detection method for monitoring PCV3 antibody level in pigs in the future.

Evaluating the pharmacokinetics of intrapulmonary administered ciprofloxacin solution for respiratory infections using in vivo and in silico PBPK rat model studies

Respiratory antibiotics have been proven clinically beneficial for the treatment of severe lung infections such as Pseudomonas aeruginosa.Maintaining a high local concentration of inhaled antibiotics for an extended time in the lung is crucial to ensure an adequate antimicrobial efficiency.In this study,we aim to investigate whether an extended exposure of ciprofloxacin(CIP),a model fluoroquinolone drug,in the lung epithelial lining fluid(ELF)could be achieved via a controlled-release formulation strategy.CIP solutions were intratracheally instilled to the rat lungs at 3 different rates,i.e.,T0h(fast),T2h(medium),and T4h(slow),to mimic different release profiles of inhaled CIP formulations in the lung.Subsequently,the concentration-time profiles of CIP in the plasma and the lung ELF were obtained,respectively,to determine topical exposure index(ELF-Plasma AUC Ratio,EPR).The in silico PBPK model,validated based on the in vivo data,was used to identify the key factors that influence the disposition of CIP in the plasma and lungs.The medium and slow rates groups exhibited much higher EPR than that fast instillation group.The ELF AUC of the medium and slow instillation groups were about 200 times higher than their plasma AUC.In contrast,the ELF AUC of the fast instillation group was only about 20 times higher than the plasma AUC.The generated whole-body PBPK rat model,validated by comparison with the in vivo data,revealed that drug pulmonary absorption rate was the key factor that determined pulmonary absorption of CIP.This study suggests that controlled CIP release from inhaled formulations may extend the exposure of CIP in the ELF post pulmonary administration.It also demonstrates that combining the proposed intratracheal installation model and in silico PBPK model is a useful approach to identify the key factors that influence the absorption and disposition of inhaled medicine.

Modeling of the resilient supply chain system from a perspective of production design changes

Building an effective resilient supply chain system (RSCS) is critical and necessary to reduce the risk of supply chain disruptions in unexpected scenarios such as COVID-19 pandemic and trade wars. To overcome the impact of insufficient raw material supply on the supply chain in mass disruption scenarios, this study proposes a novel RSCS considering product design changes (PDC). An RSCS domain model is first developed from the perspective of PDC based on a general conceptual framework, i.e., function-context-behavior-principle-state-structure (FCBPSS), which can portray complex systems under unpredictable situations. Specifically, the interaction among the structure, state and behavior of the infrastructure system and substance system is captured, and then a quantitative analysis of the change impact process is presented to evaluate the resilience of both the product and supply chain. Next, a case study is conducted to demonstrate the PDC strategy and to validate the feasibility and effectiveness of the RSCS domain model. The results show that the restructured RSCS based on the proposed strategy and model can remedy the huge losses caused by the unavailability of raw materials.

Abrogation of USP7 is an alternative strategy to downregulate PD-L1 and sensitize gastric cancer cells to T cells killing

Targeting immune checkpoints such as programmed cell death protein 1(PD-1)and programmed death ligand-1(PD-L1)have been approved for treating melanoma,gastric cancer(GC)and bladder cancer with clinical benefit.Nevertheless,many patients failed to respond to anti-PD-1/PD-L1 treatment,so it is necessary to seek an alternative strategy for traditional PD-1/PD-L1 targeting immunotherapy.Here with the data from The Cancer Genome Atlas(TCGA)and our in-house tissue library,PD-L1 expression was found to be positively correlated with the expression of ubiquitin-specific processing protease 7(USP7)in GC.Furthermore,USP7 directly interacted with PD-L1 in order to stabilize it,Gastric cancer;Immunosuppression;Cancer biologywhile abrogation of USP7 attenuated PD-L1/PD-1 interaction and sensitized cancer cells to T cell killing in vitro and in vivo.Besides,USP7 inhibitor suppressed GC cells proliferation by stabilizing P53 in vitro and in vivo.Collectively,our findings indicate that in addition to inhibiting cancer cells proliferation,USP7 inhibitor can also downregulate PD-L1 expression to enhance anti-tumor immune response simultaneously.Hence,these data posit USP7 inhibitor as an anti-proliferation agent as well as a novel therapeutic agent in PD-L1/PD-1 blockade strategy that can promote the immune response of the tumor.

Development of the triazole-fused pyrimidine derivatives as highly potent and reversible inhibitors of histone lysine specific demethylase1(LSD1/KDM1A)

Histone lysine specific demethylase 1(LSD1) has been recognized as an important modulator in post-translational process in epigenetics. Dysregulation of LSD1 has been implicated in the development of various cancers. Herein, we report the discovery of the hit compound 8 a(IC50=3.93 μmol/L) and further medicinal chemistry efforts, leading to the generation of compound 15 u(IC50=49 nmol/L, and Ki= 16 nmol/L), which inhibited LSD1 reversibly and competitively with H3 K4 me2, and was selective to LSD1 over MAO-A/B. Docking studies were performed to rationalize the potency ofcompound 15 u. Compound 15 u also showed strong antiproliferative activity against four leukemia cell lines(OCL-AML3, K562, THP-1 and U937) as well as the lymphoma cell line Raji with the IC50 values of 1.79, 1.30, 0.45, 1.22 and 1.40 μmol/L, respectively. In THP-1 cell line, 15 u significantly inhibited colony formation and caused remarkable morphological changes. Compound 15 u induced expression of CD86 and CD11 b in THP-1 cells, confirming its cellular activity and ability of inducing differentiation.The findings further indicate that targeting LSD1 is a promising strategy for AML treatment, the triazolefused pyrimidine derivatives are new scaffolds for the development of LSD1/KDM1 A inhibitors.

Over 16% efficiency all-polymer solar cells by sequential deposition

All-polymer solar cells(all-PSCs) have received extensive attention due to their excellent mechanical robustness and performance stability. However, the power conversion efficiency(PCE) of all-PSCs still lags behind those of organic solar cells(OSCs)based on non-fullerene small molecule acceptors. Herein, we report highly efficient all-PSCs via sequential deposition(SD) with donor and acceptor layers coated sequentially to optimize the film microstructure. Compared with the bulk heterojunction(BHJ)all-PSCs, an optimized morphology with vertical component distribution was achieved for the SD-processed all-PSCs due to the synergistic effect of swelling of polymer films and using additive. Such strategy involves using chlorobenzene as the first layer processing-solvent for polymer donor, chloroform as the second processing-solvent for polymer acceptor with trace 1-chloronaphthalene, efficiently promoting exciton dissociation and charge extraction and reducing trap-assisted recombination.Consequently, over 16% all-PSCs fabricated via SD method was realized for the first time, which is much higher than that(15.2%) of its BHJ counterpart and also among the highest PCEs in all-PSCs. We have further demonstrated the generality of this approach in various all-polymer systems. This work indicates that the SD method can yield excellent all-PSCs and provides a facile approach to fabricating high-performance all-PSCs.

Practical decoy-state quantum secure direct communication

Quantum secure direct communication(QSDC) has been demonstrated in both fiber-based and free-space channels using attenuated lasers. Decoy-state QSDC by exploiting four decoy states has been proposed to address the problem of photon-numbersplitting attacks caused by the use of attenuated lasers. In this study, we present an analysis of the practical aspects of decoy-state QSDC. First, we design a two-decoy-state protocol that only requires two decoy states, thereby significantly reducing experimental complexity. Second, we successfully perform full parameter optimization for a real-life QSDC system by introducing a genetic algorithm. Our simulation results show that the two-decoy-state protocol could be the best choice for developing a practical QSDC system. Furthermore, full optimization is crucial for a high-performance QSDC system. Our work serves as a major step toward the further development of practical decoy-state QSDC systems.

Structural and Expressional Variation Analyses of Mitochondrial Genomes Reveal Candidate Transcripts for the S^V Cytoplasmic Male Sterility in Wheat(Triticum aestivum L.)

Common wheat （Triticum aestivum L.） is one of the most important crops, and intra-specific wheat hybrids have obvious heterosis in yield and protein quality. Therefore, utilization of hybrid wheat varieties offers an effective way to increase yield and nutrition. Cytoplasmic male sterility （CMS） systems are a useful genetic tool for hybrid crop breeding, and are ideal models for studying the genetic interaction and cooperative function of mitochondrial and nuclear genomes in plants （Schnable and Wise, 1998; Hanson and Bentolila, 2004）.

Transition-metal-catalyzed switchable divergent cycloaddition of para-quinone methides and vinylethylene carbonates:Access to different sized medium-sized heterocycles

Divergent synthesis of medium-sized rings with controllable ring sizes represents a longstanding challenge in organic synthesis.Herein,we developed a transition-metal-catalyzed switchable divergent cycloaddition of para-quinone methides and vinylethylene carbonates by controlling the steric hindrance of substituent.Different from reported alkoxide-triggered annulations,this process undergoes a regiodivergent allylation of para-quinone methides followed by 1,6-addition reaction,providing a new route to selectively synthesize seven-to ten-membered nitrogen-containing heterocycles in high yields with excellent regioselectivities.This protocol features a broad substrate scope,wide functional group tolerance as well as operational simplicity.The reaction mechanism was investigated by conducting a series of control experiments as well as DFT calculations and the origins of the regioselectivities of the cycloaddition process were rationalized.

Self-supported porous heterostructure WC/WO_(3−x)ceramic electrode for hydrogen evolution reaction in acidic and alkaline media

Tungsten carbide(WC)-based materials are widely considered as the hydrogen evolution reaction(HER)process catalysts due to their“Pt-like”electronic structure.Nonetheless,traditional powder electrodes have a high cost,and display problems related to the process itself and the poor stability over operation time.This paper presented a self-supported asymmetric porous ceramic electrode with WO_(3-x)whiskers formed in situ on the walls of the finger-like holes and membrane surface,which was prepared by combining phase inversion tape-casting,pressureless sintering,and thermal treatment in a CO_(2) atmosphere.The optimized ceramic electrode displayed good catalytic HER activity and outstanding stability at high current densities.More specifically,it demonstrated the lowest overpotentials of 107 and 123 mV and the lowest Tafel slopes of 59.3 and 72.4 mV·dec^(-1)at 10 mA·cm^(-2)in acidic and alkaline media,respectively.This superior performance was ascribed to the structure of the ceramic membrane and the charge transfer efficiency,which was favored by the in situ developed WC/WO_(3-x)heterostructure and the oxygen vacancies.

A Portable Algorithm to Retrieve Bottom Depth of Optically Shallow Waters from Top-Of-Atmosphere Measurements

Bottom depth(H)of optically shallow waters can be retrieved from multiband imagery,where remote sensing reflectance(R_(rs))are commonly used as the input.Because of the difficulties of removing the atmospheric effects in coastal areas,quite often,there are no valid R_(rs) from satellites for the retrieval of H.More importantly,the empirical algorithms for H are hardly portable to new measurements.In this study,using data from Landsat-8 and ICESat-2 as examples,we present an approach to retrieve H directly from the top-of-atmosphere(TOA)data.It not only bypasses the requirement to correct the effects of aerosols but also shows promising portability to areas not included in algorithm development.Specifically,we use Rayleigh-corrected TOA reflectance(ρ_(rc))in the 443–2300nm range as input,along with a multilayer perceptron(MLP^(ρ_(rc))_(H)),for the retrieval of H.More than 78,000 matchup points ofρ_(rc)and H(0–25 m)were used to train MLP^(ρ_(rc))_(H),which resulted in a Mean Absolute Percentage Difference(MARD)of 8.8%and a coefficient of determination(R^(2))of 0.96.This MLP^(ρ_(rc))_(H)was further applied to Landsat-8 data of six regions not included in the training phase,generating MARD and R^(2)values of 8.3%and 0.98,respectively.In contrast,a conventional two-band ratio algorithm with R_(rs) as the input generated MARD and R^(2)values of 31.6%and 0.68 and significantly fewer H retrievals due to failures in atmospheric correction.These results indicate a breakthrough of algorithm portability of MLP^(ρ_(rc))_(H)in sensing H of optically shallow waters.