CsWRKY13,a novel WRKY transcription factor of Camellia sinensis,involved in lignin biosynthesis and accumulation

Lignin is an aromatic polymer that provides the necessary mechanical strength for the transport of water and nutrients in higher plants.Lignin biosynthesis and accumulation affect growth and development of tea plants.The degree of lignification related to the tenderness of fresh tea leaves determines the quality of tea.WRKY transcription factors play central roles in plant development and physiological processes.However,the roles of WRKY transcription factors in lignin biosynthesis of tea plants remain unclear.In this study,a WRKY gene,CsWRKY13,was cloned from tea plant'Longjing 43'.The open reading frame(ORF)of CsWRKY13 gene was 708 bp,encoding 235 amino acids.Sequence analysis showed that CsWRKY13 contained a conserved WRKYGQK amino acid sequence and a zinc-finger-like motif CX4CX23HXH.Subcellular localization showed that CsWRKY13 was localized in the nucleus.The yeast trans-activation assay showed that CsWRKY13 had no transcriptional activity.Expression analysis showed that the CsWRKY13 gene was highly expressed in the stem.Overexpression of CsWRKY13 in Arabidopsis thaliana reduced lignin content and the expression levels of genes related to lignin biosynthesis in transgenic plants.Most flavonoids pathway related genes were significantly up-regulated.This study shows that CsWRKY13 might function as a negative regulator in regulation of lignin synthesis.

Training and Recommendations on the Lower Limbs Explosive Force of Juvenile Amateur Men Sprinters

Based on the characteristics of physiological development of China's juvenile men sprinters,combined with the training mechanism of explosive force,and taking the track- and- field team of Jianshan High School in Chongqing as experimental object,this article selects the combination of one leg training methods and the combination of two legs training methods to carry out group control experiment. The result shows: each index score of the two groups of athletes is improved after training,but the characteristics of employing forces and the way of muscle work in one leg jumping exercises such as the one leg jump and step are much closer to sprint techniques. And using this kind of methods can effectively develop the special quality of juvenile sprinter.

Exploration and Analysis of the Improvement Path of College Students’Employment Ability Under the Concept of Career Planning

In the face of the fierce environment of employment,the employment of college students is a hot topic in all walks of life.The concept of career planning plays an important role in promoting the employability of college students.The career planning course for college students is a course generally offered by colleges and universities,which can help college students to better determine their employment goal and direction,and lay a solid foundation for the improvement of the employment rate of Chinese college students.This paper analyzes the reasons for the difficult employment of college graduates,puts forward the application value of career planning education in the improvement of college students’employability,points out the reasons for the difficulties of college students’employment,and makes targeted measures to improve the employability of college students under the concept of college students’career planning.

Multi-omics approach in tea polyphenol research regarding tea plant growth,development and tea processing:current technologies and perspectives

Polyphenols are one of the most important metabolites in tea due to their unique biological activities and health benefits,arousing great attention of researchers to investigate biochemical mechanisms of polyphenols during tea plant growth,development and tea processing.Although omics has been used as a major analytical platform for tea polyphenol research with some proven merits,a single-omics strategy remains a considerable challenge due to the complexity of biological system and functional processes of tea in each stage of tea production.Recent advances in multi-omics approaches and data analysis have enabled mining and mapping of enormous number of datasets at different biological scales from genotypes to phenotypes of living organisms.These new technologies combining genomics,metagenomics,transcriptomics,proteomics and/or metabolomics can pave a new avenue to address fundamental questions regarding polyphenol formation and changes in tea plants and products.Here,we review recent progresses in single-and multi-omics approaches that have been used in the field of tea polyphenol studies.The perspectives on future research and applications for improvement of tea polyphenols as well as current challenges of multi-omics studies for tea polyphenols are also discussed.

Seed-specific overexpression of cotton GhDGAT1 gene leads to increased oil accumulation in cottonseed

As the main byproduct of cotton fiber,the cotton seed yields about 1.6 times that of fiber,with its oil rich in unsaturated fatty acids,mainly linoleic acid.It is desirable for breeders to increase the oil content of cottonseed without affecting the yield and quality of cotton fiber.In this study,a seed-specific promoter-(alpha-globulin gene promoter-)driven GhDGAT1 overexpression vector(P_(aGlob)-GhDGAT1)was constructed and used to transform an upland cotton line YZ1(Gossypium hirsutum).Overexpression of the cotton gene GhDGAT1 in cotton seeds increased its total oil content from 4.7%to 13.9%in different transgenic lines and different generations.With the increase of oil content,the composition and contents of the main fatty acids in cotton seed also changed,as reflected by the contents of the main saturated fatty acids and unsaturated oleic acid.GhDGAT1 could be used to increase oil content and improve oil composition in cottonseed.

Dexmedetomidine alleviates oxygen and glucose deprivation-induced apoptosis in mesenchymal stem cell via downregulation of MKP-1

Bone marrow mesenchymal stem cell(MSC)-based therapy is a novel candidate for heart repair.But ischemiareperfusion injury leads to low viability of MSC.Dexmedetomidine(Dex)has been found to protect neurons against ischemia-reperfusion injury.It remains unknown if Dex could increase the viability of MSCs under ischemia.The present study is to observe the potential protective effect of Dex on MSCs under ischemia and its underlying mechanisms.Specific mRNAs related to myocardial ischemia in the GEO database were selected from the mRNA profiles assessed in a previous study using microarray.The most dysregulated mRNAs of the specific ones from the above study were subject to bioinformatics analysis at our laboratory.These dysregulated mRNAs possibly regulated apoptosis of cardiomyocytes and were validated in vitro for their protective effect on MSCs under ischemia.MSCs were pre-treated with Dex at 10μM concentration for 24 h under oxygen-glucose deprivation(OGD).Flow cytometry and TUNEL assay were carried out to detect apoptosis in Dex-pretreated MSCs under OGD.The relative expressions of mitogen-activated protein kinase phosphatase 1(MKP-1)and related genes were detected by quantitative polymerase chain reaction and western blotting.Microarray data analysis revealed that Dex regulates MAPK phosphatase activity.Dex significantly reduced in vitro apoptosis of MSCs under OGD,which suppressed the synthesis level of Beclin1 and light chain 3 proteins.Dex down-regulated MKP-1 expression and attenuated an OGDinduced change in the mitogen activated protein kinase 3(MAPK3)signaling pathway.Dex increases the viability of MSC and improves its tolerance to OGD in association with the MKP-1 signaling pathway,thus suggesting the potential of Dex as a novel strategy for promoting MSCs efficacy under ischemia.

Advanced development of grain boundaries in TMDs from fundamentals to hydrogen evolution application

Grain boundary(GB),as a kind of lattice defect,widely exists in two-dimensional transition metal dichalcogenides(2D TMDs),which has complex and diverse influences on the physical/chemical properties of 2D TMDs.GBs are universally considered to be a double-edged sword,although some electrical and mechanical properties of 2D TMDs would be adversely affected leading to the reduced overall quality,certain structure-oriented applications could be realized based on its unique properties.In this review,we first detailed the atomic structure characteristics of GBs and the corresponding techniques,then we systematically summarized the methods of introducing GBs into 2D TMDs.Next,we expounded unique electrical,mechanical,and chemical properties of the GBs in 2D TMDs and clarified its internal relationship with the atomic structure.Moreover,the application of GB structure in hydrogen evolution reaction(HER)is also discussed.In the end,we make a conclusion and put forward outlooks,hoping to further promote the basic research of GB and boost the wide application of 2D TMDs.

Au-Fe_(3)O_(4) dumbbell-like nanoparticles based lateral flow immunoassay for colorimetric and photothermal dual-mode detection of SARS-CoV-2 spike protein

Lateral flow immunoassay(LFIA)has become popular in laboratories,at-home testing,and medical diagnostics due to its minimal cost and user-friendliness.Nevertheless,conventional test strips based on colloidal gold can only obtain qualitative or semi-quantitative results with low sensitivity.In this work,AuFe_(3)O_(4) dumbbell-like nanoparticles were synthesized and used as the LFIA labelling marker for highly sensitive colorimetric-photothermal dual-mode detection of SARS-CoV-2 spike(S)protein.The unique dumbbell structure of Au-Fe_(3)O_(4) NPs makes it possible to combine the best features of both Au NPs and Fe_(3)O_(4) NPs.The increased surface area of these NPs enhances their LSPR effect and photothermal effect,which achieves signal amplification to increase sensitivity.The Au-Fe_(3)O_(4) NPs modified with S protein antibody could identify S protein in samples,which were recognized and accumulated on T-line by another antibody,generating color band for qualitative colorimetric detection.The T-line was irradiated by laser to obtain temperature change for quantitative detection of photothermal.In optimized conditions,the detection limit was 1.22 pg/m L,three orders of magnitude more sensitive than colorimetric detection.Finally,the approach was performed on SARS-CoV-2 pseudovirus samples and outperformed traditional colloidal gold strips.This LFIA platform exhibits significant promise for practical implementation,as it can satisfy the need for low-cost,high-sensitivity,and home-based quantitative detection for respiratory infectious diseases.

支持H.264视频跟踪的视频传输评价

论文介绍了一种基于H.264编码视频的网络传输跟踪评价方法。首先概述H.264视频编码;然后介绍了捕捉H.264编码视频特点的跟踪结构,给出一种典型的视频流量和H.264编码视频的质量特征;最后,解释了H.264特定编码机制,如分层B帧。

Lead-free thermochromic perovskites with tunable transition temperatures for smart window applications

The structural flexibility of hybrid perovskite materials allows for phase transition and consequently thermochromic properties.Here we investigate the thermochromic performance in a series of copper-based layered perovskites with organic cations having different alky chain lengths. Their transition temperature is found to be dependent on the organic cations due to molecular motion and hydrogen bond interaction, providing possibilities to prepare thermochromic semiconductors near room temperature for smart window applications.

Cell-derived biomimetic nanoparticles as a novel drug delivery system for atherosclerosis:predecessors and perspectives

Atherosclerosis is a key mechanism underlying the pathogenesis of cardiovascular disease,which is associated with high morbidity and mortality.In the field of precision medicine for the treatment of atherosclerosis,nanoparticle(NP)-mediated drug delivery systems have great potential,owing to their ability to release treatment locally.Cell-derived biomimetic NPs have attracted extensive attention at present due to their excellent targeting to atherosclerotic inflammatory sites,low immunogenicity and long blood circulation time.Here,we review the utility of cell-derived biomimetic NPs,including whole cells,cell membranes and extracellular vesicles,in the treatment of atherosclerosis.

3D printing of bioinspired compartmentalized capsular structure for controlled drug release

Drug delivery with customized combinations of drugs,controllable drug dosage,and on-demand release kinetics is critical for personalized medicine.In this study,inspired by successive opening of layered structures and compartmentalized structures in plants,we designed a multiple compartmentalized capsular structure for controlled drug delivery.The structure was designed as a series of compartments,defined by the gradient thickness of their external walls and internal divisions.Based on the careful choice and optimization of bioinks composed of gelatin,starch,and alginate,the capsular structures were successfully manufactured by fused deposition modeling three-dimensional(3 D)printing.The capsules showed fusion and firm contact between printed layers,forming complete structures without significant defects on the external walls and internal joints.Internal cavities with different volumes were achieved for different drug loading as designed.In vitro swelling demonstrated a successive dissolving and opening of external walls of different capsule compartments,allowing successive drug pulses from the capsules,resulting in the sustained release for about 410 min.The drug release was significantly prolonged compared to a single burst release from a traditional capsular design.The bioinspired design and manufacture of multiple compartmentalized capsules enable customized drug release in a controllable fashion with combinations of different drugs,drug doses,and release kinetics,and have potential for use in personalized medicine.

Large-area periodic lead halide perovskite nanostructures for lenticular printing laser displays

Lenticular printing technique provides a promising way to realize stereoscopic displays,especially,when microscopic optical structures are integrated into light-emitting materials/devices.Here,we fabricated large-area periodic structures with a spatial resolution at a wavelength scale from hybrid perovskite materials via a space-confined solution growth method.It takes advantages of both high refractive index contrast and high luminescence brightness,which allows the optical modulation on not only the reflection of illumination,but also the light emission from hybrid perovskites.The distributed feedback within these periodic structures significantly improves the degree of polarization and directionality of laser actions while their threshold is also reduced.These findings enable us to present a prototype of lenticular printing laser displays that vary emission colors at different view angles,which may find applications in creating high-resolution and high-contrast holographical images.

A self-supported heterogeneous bimetallic phosphide array electrode enables efficient hydrogen evolution from saline water splitting

Hydrogen generation from water splitting is of great prospect for the sustainable energy conversion.However,it is still challenging to explore stable and high-performance electrocatalysts toward hydrogen evolution reaction(HER)from saline water such as seawater due to the chloride corrosion.Herein,we developed a self-supported heterogeneous bimetallic phosphide(Ni_(2)P-FeP)array electrode that possesses excellent HER performance in alkaline saline water with an overpotential of 89 mV at 10 mA·cm^(−2)and long-term stability over 90 h at 200 mA·cm^(−2).The analysis showed that the heterostructure between the interfaces of Ni_(2)P-FeP plays a pivotal role in promoting the activity of catalyst.Moreover,the bimetallic phosphide nanoarrays can be employed as a shield for chlorine-corrosion resistance in the saline water,ensuring the long-term durability of hydrogen generation.When employed for alkaline saline water electrolysis,a current density of 100 mA·cm^(−2)is achieved at cell voltage of 1.68 V.This work presents an effective approach for the fabrication of high-performance electrode for HER in alkaline saline environments.

Evaluation of county-level poverty alleviation progress by deep learning and satellite observations

Poverty alleviation is one of the greatest challenges faced by low-income and middle-income countries.China,which had the largest rural poverty-stricken population,has made tremendous efforts in alleviating poverty especially since the implementation of the targeted poverty alleviation(TPA)policy in 2014,and by 2020,all national poverty-stricken counties(NPCs)have been out of poverty.This study combines deep learning with multiple satellite datasets to estimate county-level economic develop-ment from 2008 to 2019 and assess the effect of the TPA policy for 592 national poverty-stricken counties(NPCs)at country,provincial and county levels.Per capita gross domestic product(GDP)is used to measure the affluence level.From 2014 through 2019,the 592 NPCs experience an average growth rate of per capita GDP at 7.6%±0.4%,higher than the average growth rate of 310 adjacent non-NPC counties(7.3%±0.4%)and of the whole country(6.3%).We also reveal 42 counties with weak growth recently and that the average affluence level of the NPCs in 2019 is still much lower than the national or provincial averages.The inexpensive,timely and accurate method proposed here can be applied to other low-income and middle-income countries for affluence assessment.

The regulators of BCR signaling during B cell activation

B lymphocytes produce antibodies under the stimulation of specific antigens,thereby exerting an immune effect.B cells identify antigens by their surface B cell receptor(BCR),which upon stimulation,directs the cell to activate and differentiate into antibody generating plasma cells.Activation of B cells via their BCRs involves signaling pathways that are tightly controlled by various regulators.In this review,we will discuss three major BCR mediated signaling pathways(the PLC-g2 pathway,PI3K pathway and MAPK pathway)and related regulators,which were roughly divided into positive,negative and mutual-balanced regulators,and the specific regulators of the specific signaling pathway based on regulatory effects.

Formation of free-charging industry alliance for new energy vehicles

At present, the further development of new energy vehicles industry is hindered by limited consumer's participation or capital investment. Therefore, a new multilateral model of cross-industry alliance needs to arise. The advanced charging technology of Internetdistributed mobile energy can link up with many market participants closely and form an effective and multilateral win-win cross-industry alliance. This new industry alliance can realize unexpected multiple goals, for example,(1)consumers who have purchased new energy vehicles can avail free charging;(2) potential vehicle buyers can be encouraged to use new energy vehicles;(3) the new energy vehicle manufacturers can expand their production scale;(4) the new energy vehicles sellers(4 S shop) can expand their sales volume;(5) large shopping malls can attain more income;(6) financial institutions can absorb more deposits;(7) governments can further promote low-carbon traffic. This article analyzes the cross-industry alliance and its forming mechanism.1)

Pentacoordinate Phosphoranes as Versatile Reagents in Fluoroalkylation Reactions

A general method for the synthesis of bench-stable bis(difluoromethyl)pentacoordinate phosphoranes has been developed.The reaction is rapid,operationally simple,and easily scalable.The pentacoordinate phosphoranes can generate both difluoromethyl radical(·CF_(2)H)and difluorocarbene(:CF_(2))intermediates.Thus,a variety of fluoroalkylation transformations havebeen achieved by·CF_(2)H,such asoxidativedifluoromethylation of electron-deficient heterocycles,nickel/photoredox dual-catalyzed difluoromethylation of aryl bromides,and photoredox difluoromethylation of alkenes,or by:CF_(2),such as gem-difluorocyclopropanation of alkenes,base-promoted difluoromethylation of heteroatom nucleophiles,Pd-catalyzed difluoromethylation of arylboronic acids,and Cu-mediated trifluoromethylation of aryl iodides(via:CF_(2) and recombined CF_(3)-).These fluoroalkylation methods have been successfully applied to late-stage fluoroalkylation of drugs and drug-like molecules.

External field assisted hydrogen evolution reaction

As a clean,efficient,and sustainable energy,hydrogen is expected to replace traditional fossil energy.A series of studies focusing on morphology regulation,surface modification,and structural reconstruction have been devoted to improving the intrinsic catalytic activity of non-noble metal catalysts.However,complex system structure design and the mutual interference of various chemical components would hinder the further improvement of hydrogen evolution performance.In recent years,external field assisted hydrogen evolution reaction(HER)has become a new research hotspot.Herein,we systematically summarize the promoting effects of various external fields on catalytic hydrogen production from the aspects of system design and catalytic mechanism,including electric field,thermal field,optical field,magnetic field,and acoustic field.Ultimately,we discuss the key challenges facing this external field regulation strategy and put forward the prospect of future research topics.We sincerely expect that this review could not only provide a new insight into the basic mechanism of external-assisted catalysis,but also promote further research on improving HER performance from a more diverse and comprehensive perspective.