The photochemical air pollution in Xigu district of Lanshou city, Gansu Province was studied during a period of 1981-1984. The extremely high NMHC/NOx ratio and ozone level elevation after rain have been noticed. A se...The photochemical air pollution in Xigu district of Lanshou city, Gansu Province was studied during a period of 1981-1984. The extremely high NMHC/NOx ratio and ozone level elevation after rain have been noticed. A series of outdoor and indoor reaction chamber simulation experiments conducted in order to understand the specific conditions. The ozone formation under NMHC/NOx condition and the possible reason for high ozone concentration after rain are discussed.展开更多
Myeloid-derived suppressor cells(MDSCs)are a heterogenic population of immature myeloid cells with immunosuppressive effects,which undergo massive expansion during tumor progression.These cells not only support immune...Myeloid-derived suppressor cells(MDSCs)are a heterogenic population of immature myeloid cells with immunosuppressive effects,which undergo massive expansion during tumor progression.These cells not only support immune escape directly but also promote tumor invasion via various non-immunological activities.Besides,this group of cells are proved to impair the efficiency of current antitumor strategies such as chemotherapy,radiotherapy,and immunotherapy.Therefore,MDSCs are considered as potential therapeutic targets for cancer therapy.Treatment strategies targeting MDSCs have shown promising outcomes in both preclinical studies and clinical trials when administrated alone,or in combination with other anticancer therapies.In this review,we shed new light on recent advances in the biological characteristics and immunosuppressive functions of MDSCs.We also hope to propose an overview of current MDSCs-targeting therapies so as to provide new ideas for cancer treatment.展开更多
Tea plants(Camellia sinensis)are commercially cultivated in>60 countries,and their fresh leaves are processed into tea,which is the most widely consumed beverage in the world.Although several chromosome-level tea p...Tea plants(Camellia sinensis)are commercially cultivated in>60 countries,and their fresh leaves are processed into tea,which is the most widely consumed beverage in the world.Although several chromosome-level tea plant genomes have been published,they collapsed the two haplotypes and ignored a large number of allelic variations that may underlie important biological functions in this species.Here,we present a phased chromosome-scale assembly for an elite oolong tea cultivar,"Huangdan",that is well known for its high levels of aroma.Based on the two sets of haplotype genome data,we identi fi ed numerous genetic variations and a substantial proportion of allelic imbalance related to important traits,including aroma-and stress-related alleles.Comparative genomics revealed extensive structural variations as well as expansion of some gene families,such as terpene synthases(TPSs),that likely contribute to the high-aroma characteristics of the backbone parent,underlying the molecular basis for the biosynthesis of aroma-related chemicals in oolong tea.Our results uncovered the genetic basis of special features of this oolong tea cultivar,providing fundamental genomic resources to study evolution and domestication for the economically important tea crop.展开更多
The phenylalanine ammonia-lyase(PAL)gene family in tea plants(Camellia sinensis L.)encodes the enzyme that catalyzes the first reaction of the phenylpropane metabolic pathway.The present study aimed to characterize th...The phenylalanine ammonia-lyase(PAL)gene family in tea plants(Camellia sinensis L.)encodes the enzyme that catalyzes the first reaction of the phenylpropane metabolic pathway.The present study aimed to characterize the PAL genes in tea plants,and get better insights on the CsPALs in anthocyanins accumulation.Seven CsPAL genes were identified and characterized in tea plants by bioinformatics analysis.Systematic analysis of CsPALs was conducted for its phylogenetic relationship,gene structure,chromosomal location,and protein conserved motifs based on tea plant genome.The cis-elements of CsPALs were responsive to light,abiotic stress,hormone,and MYB-binding site.Furthermore,tissuespecific expression analysis showed that CsPAL4 was expressed preferentially in young leaves and buds.Correlation analysis was performed in purple-leaf tea with anthocyanin components,and it was suggested that CsPAL4 was closely related with different anthocyanin accumulated,especially with cyanidin 3-O-galactoside,cyanidin 3-O-glucoside,and delphinidin 3-O-glucoside.Additionally,the putative upstream regulation factors CsMYBs(CsMYB59,CsARR1,CsSRM1,CsMYB101,and CsMYB52)and CsbHLHs(CsbHLH104,CsbHLH3,CsbIM1,CsTCP14,and CsPIF4)could bind to the promoter of CsPALs,thereby activating its transcription.This study provides a theoretical basis for further research to elucidate the functions of the CsPAL genes.展开更多
Wearable sensing systems,as a spearhead of artificial intelligence,are playing increasingly important roles in many fields especially health monitoring.In order to achieve a better wearable experience,rationally integ...Wearable sensing systems,as a spearhead of artificial intelligence,are playing increasingly important roles in many fields especially health monitoring.In order to achieve a better wearable experience,rationally integrating the two key components of sensing systems,that is,power supplies and sensors,has become a desperate requirement.However,limited by device designs and fabrication technologies,the current integrated sensing systems still face many great challenges,such as safety,miniaturization,mechanical stability,energyefficiency,sustainability,and comfortability.In this review,the key challenges and opportunities in the current development of integrated wearable sensing systems are summarized.By summarizing the typical configurations of diverse wearable power supplies,and recent advances concerning the integrated sensing systems driven by such power supplies,the representative integrated designs,and micro/nanofabrication technologies are highlighted.Lastly,some new directions and potential solutions aiming at the device-level integration designs are outlooked.展开更多
Oocytes display a maternal-specific gene expression profile, which is switched to a zygotic profile when a haploid set of chromatin is passed on to the fertilized egg that develops into an embryo. The mechanism underl...Oocytes display a maternal-specific gene expression profile, which is switched to a zygotic profile when a haploid set of chromatin is passed on to the fertilized egg that develops into an embryo. The mechanism underlying this transcription reprogramming is currently unknown. Here we demonstrate that by the time when transcription is shut down in germinal vesicle oocytes, a range of general transcription factors and transcriptional regulators are dissociated from the chromatin. The global dissociation of chromatin factors （CFs） disrupts physical contacts between the chromatin and CFs and leads to erasure of the maternal transcription program at the functional level. Critical transcription factors and regulators remain separated from chromatin for a prolonged period, and become re-associated with chromatin shortly after pronuclear formation. This is followed temporally by the re-establishment of nuclear functions such as DNA replication and transcription. We propose that the maternal transcription program is erased during oogenesis to generate a relatively naive chromatin and the zygotic transcription program is rebuilt de novo after fertilization. This process is termed as the ＂erase-and-rebuild＂ process, which is used to reset the transcription program, and most likely other nuclear processes as well, from a maternal one to that of the embryo. We further show in the accompanying paper （Gao T, et al., Cell Res 2007; 17：135-150.） that the same strategy is also employed to reprogram transcriptional profiles in somatic cell nuclear transfer and parthenogenesis, suggesting that this model is universally applicable to all forms of transcriptional reprogramming during early embryogenesis. Displacement of CFs from chromatin also offers an explanation for the phenomenon of transcription silence during the maternal to zygotic transition.展开更多
Although the principles of synthetic biology were initially established in model bacteria,microbial producers,extremophiles and gut microbes have now emerged as valuable prokaryotic chassis for biological engineering....Although the principles of synthetic biology were initially established in model bacteria,microbial producers,extremophiles and gut microbes have now emerged as valuable prokaryotic chassis for biological engineering.Extending the host range in which designed circuits can function reliably and predictably presents a major challenge for the concept of synthetic biology to materialize.In this work,we systematically characterized the cross-species universality of two transcriptional regulatory modules—the T7 RNA polymerase activator module and the repressors module—in three non-model microbes.We found striking linear relationships in circuit activities among different organisms for both modules.Parametrized model fitting revealed host non-specific parameters defining the universality of both modules.Lastly,a genetic NOT gate and a band-pass filter circuit were constructed from these modules and tested in non-model organisms.Combined models employing host non-specific parameters were successful in quantitatively predicting circuit behaviors,underscoring the potential of universal biological parts and predictive modeling in synthetic bioengineering.展开更多
The physical,emotional,and caregiving quality of caregivers for children with malignant solid tumors is significantly influenced by mental toughness.The definition of mental toughness,study methods,primary influencing...The physical,emotional,and caregiving quality of caregivers for children with malignant solid tumors is significantly influenced by mental toughness.The definition of mental toughness,study methods,primary influencing factors,and intervention strategies for the mental toughness of caregivers of children with malignant solid tumors will be examined in this paper.To improve the mental toughness of caregivers of children with malignant solid tumors,it is recommended that future studies enhance the number of intervention research methods and establish particular evaluation tools.展开更多
The therapeutic efficacy of metformin in prostate cancer(PCa)appears uncertain based on various clinical trials.Metformin treatment failure may be attributed to the high frequency of transcriptional dysregulation,whic...The therapeutic efficacy of metformin in prostate cancer(PCa)appears uncertain based on various clinical trials.Metformin treatment failure may be attributed to the high frequency of transcriptional dysregulation,which leads to drug resistance.However,the underlying mechanism is still unclear.In this study,we found evidences that metformin resistance in PCa cells may be linked to cell cycle reactivation.Super-enhancers(SEs),crucial regulatory elements,have been shown to be associated with drug resistance in various cancers.Our analysis of SEs in metformin-resistant(MetR)PCa cells revealed a correlation with Prostaglandin Reductase 1(PTGR1)expression,which was identified as significantly increased in a cluster of cells with metformin resistance through single-cell transcriptome sequencing.Our functional experiments showed that PTGR1 overexpression accelerated cell cycle progression by promoting progression from the G0/G1 to the S and G2/M phases,resulting in reduced sensitivity to metformin.Additionally,we identified key transcription factors that significantly increase PTGR1 expression,such as SRF and RUNX3,providing potential new targets to address metformin resistance in PCa.In conclusion,our study sheds new light on the cellular mechanism underlying metformin resistance and the regulation of the SE-TFs-PTGR1 axis,offering potential avenues to enhance metformin’s therapeutic efficacy in PCa.展开更多
A knowledge graph(KG)is a knowledge base that integrates and represents data based on a graph-structured data model or topology.Geoscientists have made efforts to construct geosciencerelated KGs to overcome semantic h...A knowledge graph(KG)is a knowledge base that integrates and represents data based on a graph-structured data model or topology.Geoscientists have made efforts to construct geosciencerelated KGs to overcome semantic heterogeneity and facilitate knowledge representation,data integration,and text analysis.However,there is currently no comprehensive paleontology KG or data-driven discovery based on it.In this study,we constructed a two-layer model to represent the ordinal hierarchical structure of the paleontology KG following a top-down construction process.An ontology containing 19365 concepts has been defined up to 2023.On this basis,we derived the synonymy list based on the paleontology KG and designed corresponding online functions in the OneStratigraphy database to showcase the use of the KG in paleontological research.展开更多
The Ordovician rocks on the Qinghai-Tibetan Plateau represent the oldest non-metamorphic strata,and are critical to understanding the history of regional geology and biotic evolution of the entire plateau.Strata of Fl...The Ordovician rocks on the Qinghai-Tibetan Plateau represent the oldest non-metamorphic strata,and are critical to understanding the history of regional geology and biotic evolution of the entire plateau.Strata of Floian,Darriwilian,Sandbian,Katian and Hirnantian are represented in the plateau with a hiatus of variable duration occurring underneath the basal Ordovician across the area.Five stratigraphical regions,including the Himalaya,Gangdise-Zayu,Qiangtang-Qamdo,Songpan-Garze,and Karakoram-Kunlun-Altun,are differentiated for the Ordovician strata,which are correlated with their equivalents in the Sibumasu,Indochina,Qaidam-Qilian,Tarim-Tianshan,and the Yangtze(western margin)stratigraphical regions.On the QinghaiTibetan Plateau,graptolites,conodonts,and cephalopods are the most common and useful fossils for the Ordovician biostratigraphy.The Ordovician biotas of the Qinghai-Tibetan Plateau bear some distinguishable palaeobiogeographical signatures,among which the cephalopods are characterized by the flourishing actinocerids of North China affinity in the Early-Middle Ordovician,and by the thriving lituitids and orthocerids of South China affinity in the Middle-Late Ordovician.Fossil occurrences and their palaeobiogeographical evolution provide critical evidence bearing on the reconstruction of the geological history of the Qinghai-Tibetan Plateau and surrounding terranes in northeastern peri-Gondwana.The stratigraphical successions of the Cambrian-Ordovician transition in the Himalaya and Lhasa and nearby Sibumasu terranes were significantly affected by the Kurgiakh Orogeny,which resulted in the extensive unconformity between the Ordovician and the underlying rocks in most areas of the Qinghai-Tibetan Plateau.In southern Xizang,a warm-water biota of Middle Ordovician age was recovered from oolitic limestones,suggesting a likely palaeogeographical location in low-latitudes near the equator.In the Himalaya and Sibumasu regions,the Upper Ordovician was typified by the occurrence of red carbonates with distinctive展开更多
Infectious diseases severely threaten public health and global biosafety.In addition to transmission through the air,pathogenic microorganisms have also been detected in environmental liquid samples,such as sewage wat...Infectious diseases severely threaten public health and global biosafety.In addition to transmission through the air,pathogenic microorganisms have also been detected in environmental liquid samples,such as sewage water.Conventional biochemical detection methodologies are time-consuming and cost-ineffective,and their detection limits hinder early diagnosis.In the present study,ultrafine plasmonic fiber probes with a diameter of 125μm are fabricated for clustered regularly interspaced short palindromic repeats/CRISPR-associated protein(CRISPR/Cas)-12a-mediated sensing of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Single-stranded DNA exposed on the fiber surface is trans-cleaved by the Cas12a enzyme to release gold nanoparticles that are immobilized onto the fiber surface,causing a sharp reduction in the surface plasmon resonance(SPR)wavelength.The proposed fiber probe is virus-specific with the limit of detection of~2,300 copies/ml,and genomic copy numbers can be reflected as shifts in wavelengths.A total of 21 sewage water samples have been examined,and the data obtained are consistent with those of quantitative polymerase chain reaction(qPCR).In addition,the Omicron variant and its mutation sites have been fast detected using S gene-specific Cas12a.This study provides an accurate and convenient approach for the real-time surveillance of microbial contamination in sewage water.展开更多
The sea surface wind field is an important physical parameter in oceanography and meteorology.With the continuous refinement of numerical weather prediction,air-sea interface materials,energy exchange,and other studie...The sea surface wind field is an important physical parameter in oceanography and meteorology.With the continuous refinement of numerical weather prediction,air-sea interface materials,energy exchange,and other studies,three-dimensional(3D)wind field distribution at local locations on the sea surface must be measured accurately.The current in-situ observation of sea surface wind parameters is mainly achieved through the installation of wind sensors on ocean data buoys.However,the results obtained from this single-point measurement method cannot reflect wind field distribution in a vertical direction above the sea surface.Thus,the present paper proposes a theoretical framework for the optimal inversion of the 3D wind field structure variation in the area where the buoy is located.The variation analysis method is first used to reconstruct the wind field distribution at different heights of the buoy,after which theoretical analysis verification and numerical simulation experiments are conducted.The results indicate that the use of variational methods to reconstruct 3D wind fields is significantly effective in eliminating disturbance errors in observations,which also verifies the correctness of the theoretical analysis of this method.The findings of this article can provide a reference for the layout optimization design of wind measuring instruments in buoy observation systems and also provide theoretical guidance for the design of new observation buoys in the future.展开更多
[Objectives]To study the effects of fungi Fusarium sp.to rhizosphere soil and physiological characteristics of Camellia oleifera Abel.[Methods]We investigated the effects of Fusarium sp.to rhizosphere soil nutrient el...[Objectives]To study the effects of fungi Fusarium sp.to rhizosphere soil and physiological characteristics of Camellia oleifera Abel.[Methods]We investigated the effects of Fusarium sp.to rhizosphere soil nutrient element content and metabolites of C.oleifera.C.oleifera was inoculated with the suspension of Fusarium sp.in pot experiments and ammonium-N,available phosphorus,available potassi-um,organic matter,enzymes and pH of rhizosphere soil,MDA content,activity of SOD,POD of C.oleifera leaves were analyzed.[Results]Fusarium sp.stress significantly inhibited soil enzyme activities and significantly reduced available phosphorus content,especially for phospha-tase and sucrase.Antioxidant enzyme activities in C.oleifera tissues showed that Fusarium sp.stress significantly increased MDA and SOD enzyme activities and decreased POD enzyme activity.Especially,SOD enzyme activity was elevated by 53.86%compared with the CK group.In addition,analysis of the content of major metabolites in C.oleifera leaves showed that Fusarium sp.stress significantly reduced the content of total flavonoids,quercetin,isoquercitrin and isoquercitrin in C.oleifera leaves by 7.80%,50.00%and 75.90%,respectively.[Conclusions]Our results are an important step which showed strong resistance of C.oleifera and can give a novel insight for researches on the effects in the rhizosphere soil enzyme,soil nutrient elements and metabolites of C.oleifera under the Fusarium sp.too.展开更多
This paper presents the model of calculating the total friction moment of space gyroscope ball bearings which usually work under ultra-low oscillatory motion and are very sensitive to the friction moment. The aim is t...This paper presents the model of calculating the total friction moment of space gyroscope ball bearings which usually work under ultra-low oscillatory motion and are very sensitive to the friction moment. The aim is to know the proportion of the friction moment caused by each frictional source in the bearing＇s total friction moment, which is helpful to optimize the bearing design to deduce the friction moment. In the model, the cage dynamic equations considering six degree-of-freedom and the balls dynamic equations considering two degree-of-freedom were solved.The good trends with different loads between the measured friction moments and computational results prove that the model under constant rate was validated. The computational results show that when the speed was set at 5 r/min, the bearing＇s maximum total friction moment when oscillation occurred was obviously larger than that occurred at a constant rate. At the onset of each oscillatory motion, the proportion of the friction moment caused by cage in the bearing＇s total friction moment was very high, and it increased with the increasing speed. The analyses of different cage thicknesses and different clearances between cage pocket and ball show that smaller thickness and clearance were preferred.展开更多
Two-dimensional MXene-based film materials as flexible electrodes have been widely studied in wearable microsupercapacitors(MSCs).However,the existence of strong van derWaals interactions leads to serious self-stackin...Two-dimensional MXene-based film materials as flexible electrodes have been widely studied in wearable microsupercapacitors(MSCs).However,the existence of strong van derWaals interactions leads to serious self-stacking ofMXene layers,resulting in poor ionic dynamics and loss of active sites,which causes MXene film electrodes to exhibit low capacitance and poor rate performance in practical studies.To solve this,a frame-structured hybrid film(labeled as CN-MX hybrid film)is constructed by introducing intercalating agents(nanometer g-C_(3)N_(4))into MXene layers.In this unique hybrid film,the g-C_(3)N_(4)nanoparticles rationally occupy the interspace between MXene layers so as to alleviate layer stacking,thus effectively expanding the electrochemically active surface and promoting proton transfer.Synergistic pseudocapacitance inducted by g-C_(3)N_(4)surface groups,consequently,the CN-MX hybrid film electrode achieves an enhanced capacitive capability.In the three-electrode system,this frame-structured film electrode exhibits an ultra-high areal capacitance of 1932.8 mF cm^(−2).The assembled symmetry flexible MSC device based on CN-MX hybrid film can achieve an energy density of 2.28μWh cm^(−2)at 0.075 mW cm^(−2),as well as a superior cyclic stability with 90.4%retention after 700 cycles in alternating 90o bending and releasing states,revealing its potential in practical applications.展开更多
Wave-transparent ceramic matrix composites for the high temperature use should possess excellent oxidation resistance. In this work, Si3N4f/SiO2 composites with different fiber content were fabricated by filament wind...Wave-transparent ceramic matrix composites for the high temperature use should possess excellent oxidation resistance. In this work, Si3N4f/SiO2 composites with different fiber content were fabricated by filament winding and sol gel method. The oxidation resistance was investigated by tracking the response of flexural strength to the testing temperature. The results show that the flexural strength and toughness of the composites with fiber content of over 37% can reach high levels at around 175.0 MPa and 6.2 MPa m^1/2, respectively. After 1 h oxidation at 1100℃, the flexural strength drops a lot but can still reach 114.4 MPa, which is high enough to ensure the safety of structures. However, when the oxidation temperature rises to 1200–1400℃, the flexural strengths continue to fall to a relatively low level at 50.0–66.4 MPa. The degradation at high temperatures is caused by the combination of over strong interfacial bonding, the damage of fiber and the crystallization of silica matrix.展开更多
This paper reports a method for strand tension in anchor spans considering rotation.A kind of co-moved coordinate system,a saddle local coordinate system,was set up.This system implemented the rotation of the splay sa...This paper reports a method for strand tension in anchor spans considering rotation.A kind of co-moved coordinate system,a saddle local coordinate system,was set up.This system implemented the rotation of the splay saddle through the rotation of the coordinate system,and all calculations proceeded in this coordinate system.Considering the rotation of the anchoring surface by the rotation of the local coordinate system of the anchoring surface,the anchorage point coordinates of strands were transformed to the local sadle coordinate system.There was a two-layer iteration adopted in the calculation.In the inner iteration,the cable force at the end of the vertical bend was taken as the variable,and the ordinate of the anchorage point was taken as the target value.In the outer iteration,the vertical tangential angle at the end of the vertical bend was taken as the variable,and the ordinate of the anchorage point was taken as the target value.The method carried out the rotation of the splay saddle and anchor surface and was simple,convenient and without approximation.The effect of rotation was considered precisely;it showed stability during the process of two-layer iteration,powerful adaptation and higher efficiency and had been successfully applied in the construction control of the Wufengshan Yangtze River Bridge,the world's first kilometer-level combined highway and railway suspension bridge.展开更多
Plants have evolved regulatory mechanisms at multiple levels to regulate gene expression in order to improve their cold adaptability.However,limited information is available regarding the stress response at the chroma...Plants have evolved regulatory mechanisms at multiple levels to regulate gene expression in order to improve their cold adaptability.However,limited information is available regarding the stress response at the chromatin and translational levels.Here,we characterize the chromatin accessibility,transcriptional,and translational landscapes of tea plants in vivo under chilling stress for the first time.Chilling stress signi ficantly affected both the transcription and translation levels as well as the translation efficiency of tea plants.A total of 3010 genes that underwent rapid and independent translation under chilling stress were observed,and they were signi ficantly enriched in the photosynthesis-antenna protein and phenylpropanoid biosynthesis pathways.A set of genes that were signi ficantly responsive to cold at the transcription and translation levels,including four(+)-neomenthol dehydrogenases(MNDs)and two(E)-nerolidol synthases(NESs)arranged in tandem on the chromosomes,were also found.We detected potential upstream open reading frames(uORFs)on 3082 genes and found that tea plants may inhibit the overall expression of genes by enhancing the translation of uORFs under chilling stress.In addition,we identi fied distal transposase hypersensitive sites(THSs)and proximal THSs and constructed a transcriptional regulatory network for tea plants under chilling stress.We also identi fied 13 high-con fidence transcription factors(TFs)that may play a crucial role in cold regulation.These results provide valuable information regarding the potential transcriptional regulatory network in plants and help to clarify how plants exhibit flexible responses to chilling stress.展开更多
文摘The photochemical air pollution in Xigu district of Lanshou city, Gansu Province was studied during a period of 1981-1984. The extremely high NMHC/NOx ratio and ozone level elevation after rain have been noticed. A series of outdoor and indoor reaction chamber simulation experiments conducted in order to understand the specific conditions. The ozone formation under NMHC/NOx condition and the possible reason for high ozone concentration after rain are discussed.
基金This work was supported by the National Natural Science Foundation of China(Grant No.81872489,82073369).
文摘Myeloid-derived suppressor cells(MDSCs)are a heterogenic population of immature myeloid cells with immunosuppressive effects,which undergo massive expansion during tumor progression.These cells not only support immune escape directly but also promote tumor invasion via various non-immunological activities.Besides,this group of cells are proved to impair the efficiency of current antitumor strategies such as chemotherapy,radiotherapy,and immunotherapy.Therefore,MDSCs are considered as potential therapeutic targets for cancer therapy.Treatment strategies targeting MDSCs have shown promising outcomes in both preclinical studies and clinical trials when administrated alone,or in combination with other anticancer therapies.In this review,we shed new light on recent advances in the biological characteristics and immunosuppressive functions of MDSCs.We also hope to propose an overview of current MDSCs-targeting therapies so as to provide new ideas for cancer treatment.
基金This research was funded by the Fujian Province"2011 Collaborative Innovation Center",the Chinese Oolong Tea Industry Innovation Center special project(J 2015-75)the National Natural Science Foundation of China(31701874)+3 种基金the Major Special Project of Scientific and Technological Innovation on Anxi Tea(AX2021001)the Earmarked Fund for the China Agriculture Research System(CARS-19)the Scientific Research Foundation of the Graduate School of Fujian Agriculture and Forestry University(324-1122yb060)the Scientific Research Foundation of Horticulture College of Fujian Agriculture and Forestry University(2018B02).
文摘Tea plants(Camellia sinensis)are commercially cultivated in>60 countries,and their fresh leaves are processed into tea,which is the most widely consumed beverage in the world.Although several chromosome-level tea plant genomes have been published,they collapsed the two haplotypes and ignored a large number of allelic variations that may underlie important biological functions in this species.Here,we present a phased chromosome-scale assembly for an elite oolong tea cultivar,"Huangdan",that is well known for its high levels of aroma.Based on the two sets of haplotype genome data,we identi fi ed numerous genetic variations and a substantial proportion of allelic imbalance related to important traits,including aroma-and stress-related alleles.Comparative genomics revealed extensive structural variations as well as expansion of some gene families,such as terpene synthases(TPSs),that likely contribute to the high-aroma characteristics of the backbone parent,underlying the molecular basis for the biosynthesis of aroma-related chemicals in oolong tea.Our results uncovered the genetic basis of special features of this oolong tea cultivar,providing fundamental genomic resources to study evolution and domestication for the economically important tea crop.
基金This research was funded by the Fujian Province“2011 Collaborative Innovation Center”,Chinese Oolong Tea Industry Innovation Center special project(Grant No.J2015-75)China Agriculture Research System of MOF andMARA(GrantNo.CARS-19)Special Fund for Science and Technology Innovation of Fujian Zhang Tianfu Tea Development Foundation(Grant No.FJZTF01).
文摘The phenylalanine ammonia-lyase(PAL)gene family in tea plants(Camellia sinensis L.)encodes the enzyme that catalyzes the first reaction of the phenylpropane metabolic pathway.The present study aimed to characterize the PAL genes in tea plants,and get better insights on the CsPALs in anthocyanins accumulation.Seven CsPAL genes were identified and characterized in tea plants by bioinformatics analysis.Systematic analysis of CsPALs was conducted for its phylogenetic relationship,gene structure,chromosomal location,and protein conserved motifs based on tea plant genome.The cis-elements of CsPALs were responsive to light,abiotic stress,hormone,and MYB-binding site.Furthermore,tissuespecific expression analysis showed that CsPAL4 was expressed preferentially in young leaves and buds.Correlation analysis was performed in purple-leaf tea with anthocyanin components,and it was suggested that CsPAL4 was closely related with different anthocyanin accumulated,especially with cyanidin 3-O-galactoside,cyanidin 3-O-glucoside,and delphinidin 3-O-glucoside.Additionally,the putative upstream regulation factors CsMYBs(CsMYB59,CsARR1,CsSRM1,CsMYB101,and CsMYB52)and CsbHLHs(CsbHLH104,CsbHLH3,CsbIM1,CsTCP14,and CsPIF4)could bind to the promoter of CsPALs,thereby activating its transcription.This study provides a theoretical basis for further research to elucidate the functions of the CsPAL genes.
基金GRF,Hong Kong,Grant/Award Number:CityU 11305218Natural Science Foundation of Guangdong Province,Grant/Award Number:2019A1515011819Songshan Lake Materials Laboratory grant,Grant/Award Number:Y8D1041Z111。
文摘Wearable sensing systems,as a spearhead of artificial intelligence,are playing increasingly important roles in many fields especially health monitoring.In order to achieve a better wearable experience,rationally integrating the two key components of sensing systems,that is,power supplies and sensors,has become a desperate requirement.However,limited by device designs and fabrication technologies,the current integrated sensing systems still face many great challenges,such as safety,miniaturization,mechanical stability,energyefficiency,sustainability,and comfortability.In this review,the key challenges and opportunities in the current development of integrated wearable sensing systems are summarized.By summarizing the typical configurations of diverse wearable power supplies,and recent advances concerning the integrated sensing systems driven by such power supplies,the representative integrated designs,and micro/nanofabrication technologies are highlighted.Lastly,some new directions and potential solutions aiming at the device-level integration designs are outlooked.
文摘Oocytes display a maternal-specific gene expression profile, which is switched to a zygotic profile when a haploid set of chromatin is passed on to the fertilized egg that develops into an embryo. The mechanism underlying this transcription reprogramming is currently unknown. Here we demonstrate that by the time when transcription is shut down in germinal vesicle oocytes, a range of general transcription factors and transcriptional regulators are dissociated from the chromatin. The global dissociation of chromatin factors （CFs） disrupts physical contacts between the chromatin and CFs and leads to erasure of the maternal transcription program at the functional level. Critical transcription factors and regulators remain separated from chromatin for a prolonged period, and become re-associated with chromatin shortly after pronuclear formation. This is followed temporally by the re-establishment of nuclear functions such as DNA replication and transcription. We propose that the maternal transcription program is erased during oogenesis to generate a relatively naive chromatin and the zygotic transcription program is rebuilt de novo after fertilization. This process is termed as the ＂erase-and-rebuild＂ process, which is used to reset the transcription program, and most likely other nuclear processes as well, from a maternal one to that of the embryo. We further show in the accompanying paper （Gao T, et al., Cell Res 2007; 17：135-150.） that the same strategy is also employed to reprogram transcriptional profiles in somatic cell nuclear transfer and parthenogenesis, suggesting that this model is universally applicable to all forms of transcriptional reprogramming during early embryogenesis. Displacement of CFs from chromatin also offers an explanation for the phenomenon of transcription silence during the maternal to zygotic transition.
基金National Natural Science Foundation of China,Grant/Award Number:12090054National Key Research and Development Programof China,Grant/Award Numbers:2020YFA0906900,2021YFF1200500。
文摘Although the principles of synthetic biology were initially established in model bacteria,microbial producers,extremophiles and gut microbes have now emerged as valuable prokaryotic chassis for biological engineering.Extending the host range in which designed circuits can function reliably and predictably presents a major challenge for the concept of synthetic biology to materialize.In this work,we systematically characterized the cross-species universality of two transcriptional regulatory modules—the T7 RNA polymerase activator module and the repressors module—in three non-model microbes.We found striking linear relationships in circuit activities among different organisms for both modules.Parametrized model fitting revealed host non-specific parameters defining the universality of both modules.Lastly,a genetic NOT gate and a band-pass filter circuit were constructed from these modules and tested in non-model organisms.Combined models employing host non-specific parameters were successful in quantitatively predicting circuit behaviors,underscoring the potential of universal biological parts and predictive modeling in synthetic bioengineering.
文摘The physical,emotional,and caregiving quality of caregivers for children with malignant solid tumors is significantly influenced by mental toughness.The definition of mental toughness,study methods,primary influencing factors,and intervention strategies for the mental toughness of caregivers of children with malignant solid tumors will be examined in this paper.To improve the mental toughness of caregivers of children with malignant solid tumors,it is recommended that future studies enhance the number of intervention research methods and establish particular evaluation tools.
基金This study was supported by the National Natural Science Foundation of China(82072813,82203557,82103358)The Science and Technology Development Fund,Macao SAR(File no.0031/2021/A,0090/2022/A)+1 种基金GuangDong Basic and Applied Basic Research Foundation(2020A1515110792,2022A1515010342,2020A1515110640,2020A1515011290)Guangzhou Municipal Science and Technology Project(202201010053).We thank Mr.Yuanqi Feng for bioinformatic support and discussion,Mr.Zuqing Deng for technical assistance and discussion.
文摘The therapeutic efficacy of metformin in prostate cancer(PCa)appears uncertain based on various clinical trials.Metformin treatment failure may be attributed to the high frequency of transcriptional dysregulation,which leads to drug resistance.However,the underlying mechanism is still unclear.In this study,we found evidences that metformin resistance in PCa cells may be linked to cell cycle reactivation.Super-enhancers(SEs),crucial regulatory elements,have been shown to be associated with drug resistance in various cancers.Our analysis of SEs in metformin-resistant(MetR)PCa cells revealed a correlation with Prostaglandin Reductase 1(PTGR1)expression,which was identified as significantly increased in a cluster of cells with metformin resistance through single-cell transcriptome sequencing.Our functional experiments showed that PTGR1 overexpression accelerated cell cycle progression by promoting progression from the G0/G1 to the S and G2/M phases,resulting in reduced sensitivity to metformin.Additionally,we identified key transcription factors that significantly increase PTGR1 expression,such as SRF and RUNX3,providing potential new targets to address metformin resistance in PCa.In conclusion,our study sheds new light on the cellular mechanism underlying metformin resistance and the regulation of the SE-TFs-PTGR1 axis,offering potential avenues to enhance metformin’s therapeutic efficacy in PCa.
基金supported by the National Natural Science Foundation of China(Nos.41725007,42250104,41830323,42002015,and 42302001)the Fundamental Research Funds for the Central Universities(Nos.020614380168,JZ2023HGQA0144 and JZ2023HGTA0175)。
文摘A knowledge graph(KG)is a knowledge base that integrates and represents data based on a graph-structured data model or topology.Geoscientists have made efforts to construct geosciencerelated KGs to overcome semantic heterogeneity and facilitate knowledge representation,data integration,and text analysis.However,there is currently no comprehensive paleontology KG or data-driven discovery based on it.In this study,we constructed a two-layer model to represent the ordinal hierarchical structure of the paleontology KG following a top-down construction process.An ontology containing 19365 concepts has been defined up to 2023.On this basis,we derived the synonymy list based on the paleontology KG and designed corresponding online functions in the OneStratigraphy database to showcase the use of the KG in paleontological research.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research(Grant No.2019QZKK0706)the National Natural Science Foundation of China(Grant Nos.42030510,42002009,42102013)+2 种基金the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(Grant No.XDB26000000)the State Key Laboratory of Palaeobiology and Stratigraphy(Grant Nos.20201104,20221103)the Chinese Academy of Geological Sciences(Grant No.DD20221829)。
文摘The Ordovician rocks on the Qinghai-Tibetan Plateau represent the oldest non-metamorphic strata,and are critical to understanding the history of regional geology and biotic evolution of the entire plateau.Strata of Floian,Darriwilian,Sandbian,Katian and Hirnantian are represented in the plateau with a hiatus of variable duration occurring underneath the basal Ordovician across the area.Five stratigraphical regions,including the Himalaya,Gangdise-Zayu,Qiangtang-Qamdo,Songpan-Garze,and Karakoram-Kunlun-Altun,are differentiated for the Ordovician strata,which are correlated with their equivalents in the Sibumasu,Indochina,Qaidam-Qilian,Tarim-Tianshan,and the Yangtze(western margin)stratigraphical regions.On the QinghaiTibetan Plateau,graptolites,conodonts,and cephalopods are the most common and useful fossils for the Ordovician biostratigraphy.The Ordovician biotas of the Qinghai-Tibetan Plateau bear some distinguishable palaeobiogeographical signatures,among which the cephalopods are characterized by the flourishing actinocerids of North China affinity in the Early-Middle Ordovician,and by the thriving lituitids and orthocerids of South China affinity in the Middle-Late Ordovician.Fossil occurrences and their palaeobiogeographical evolution provide critical evidence bearing on the reconstruction of the geological history of the Qinghai-Tibetan Plateau and surrounding terranes in northeastern peri-Gondwana.The stratigraphical successions of the Cambrian-Ordovician transition in the Himalaya and Lhasa and nearby Sibumasu terranes were significantly affected by the Kurgiakh Orogeny,which resulted in the extensive unconformity between the Ordovician and the underlying rocks in most areas of the Qinghai-Tibetan Plateau.In southern Xizang,a warm-water biota of Middle Ordovician age was recovered from oolitic limestones,suggesting a likely palaeogeographical location in low-latitudes near the equator.In the Himalaya and Sibumasu regions,the Upper Ordovician was typified by the occurrence of red carbonates with distinctive
基金supported by the National Natural Science Foundation of China(no.U1813207)the State Key Research Development Program of China(no.YS2022YFB3200011)+4 种基金Stabilization Support Program for Higher Education Institutions of Shenzhen(no.20200812115548001)Shenzhen Bay Laboratory Open Fund Project(no.SZBL2021080601012)High-end Talent Scientific Research Startup Project(no.827-000636)Shenzhen Science and Technology R&D and Innovation Foundation(no.JCJY20200109105608771)The authors acknowledge the support and funding of King Khalid University through Research Center for Advanced Materials Science(RCAMS)under grant no.RCAMS/KKU/0010/21.
文摘Infectious diseases severely threaten public health and global biosafety.In addition to transmission through the air,pathogenic microorganisms have also been detected in environmental liquid samples,such as sewage water.Conventional biochemical detection methodologies are time-consuming and cost-ineffective,and their detection limits hinder early diagnosis.In the present study,ultrafine plasmonic fiber probes with a diameter of 125μm are fabricated for clustered regularly interspaced short palindromic repeats/CRISPR-associated protein(CRISPR/Cas)-12a-mediated sensing of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Single-stranded DNA exposed on the fiber surface is trans-cleaved by the Cas12a enzyme to release gold nanoparticles that are immobilized onto the fiber surface,causing a sharp reduction in the surface plasmon resonance(SPR)wavelength.The proposed fiber probe is virus-specific with the limit of detection of~2,300 copies/ml,and genomic copy numbers can be reflected as shifts in wavelengths.A total of 21 sewage water samples have been examined,and the data obtained are consistent with those of quantitative polymerase chain reaction(qPCR).In addition,the Omicron variant and its mutation sites have been fast detected using S gene-specific Cas12a.This study provides an accurate and convenient approach for the real-time surveillance of microbial contamination in sewage water.
基金supported by the Key R&D Program of Shandong Province, China (No. 2023ZLYS01)the National Natural Science Foundation of China (Nos. 91730304 and 41575026)+3 种基金the National Key Research and Development Plan Project (No. 2022 YFC3104200)the Major Innovation Special Project of Qilu University of Technology (Shandong Academy of Sciences) Science Education Industry Integration Pilot Project (No. 2023HYZX01)the ‘Taishan Scholars’ Construction Projectthe Special funds of Laoshan Laboratory
文摘The sea surface wind field is an important physical parameter in oceanography and meteorology.With the continuous refinement of numerical weather prediction,air-sea interface materials,energy exchange,and other studies,three-dimensional(3D)wind field distribution at local locations on the sea surface must be measured accurately.The current in-situ observation of sea surface wind parameters is mainly achieved through the installation of wind sensors on ocean data buoys.However,the results obtained from this single-point measurement method cannot reflect wind field distribution in a vertical direction above the sea surface.Thus,the present paper proposes a theoretical framework for the optimal inversion of the 3D wind field structure variation in the area where the buoy is located.The variation analysis method is first used to reconstruct the wind field distribution at different heights of the buoy,after which theoretical analysis verification and numerical simulation experiments are conducted.The results indicate that the use of variational methods to reconstruct 3D wind fields is significantly effective in eliminating disturbance errors in observations,which also verifies the correctness of the theoretical analysis of this method.The findings of this article can provide a reference for the layout optimization design of wind measuring instruments in buoy observation systems and also provide theoretical guidance for the design of new observation buoys in the future.
基金Supported by Key Field Project of Education Department of Guizhou Province(QJHKYZ[2021]044)Forestry Research Project of Guizhou Province(QLKH[2021]11)+1 种基金Project of Guizhou Provincial Characteristic Key Laboratory(QJHKY[2021]002)National Natural Science Foundation of China(41761010).
文摘[Objectives]To study the effects of fungi Fusarium sp.to rhizosphere soil and physiological characteristics of Camellia oleifera Abel.[Methods]We investigated the effects of Fusarium sp.to rhizosphere soil nutrient element content and metabolites of C.oleifera.C.oleifera was inoculated with the suspension of Fusarium sp.in pot experiments and ammonium-N,available phosphorus,available potassi-um,organic matter,enzymes and pH of rhizosphere soil,MDA content,activity of SOD,POD of C.oleifera leaves were analyzed.[Results]Fusarium sp.stress significantly inhibited soil enzyme activities and significantly reduced available phosphorus content,especially for phospha-tase and sucrase.Antioxidant enzyme activities in C.oleifera tissues showed that Fusarium sp.stress significantly increased MDA and SOD enzyme activities and decreased POD enzyme activity.Especially,SOD enzyme activity was elevated by 53.86%compared with the CK group.In addition,analysis of the content of major metabolites in C.oleifera leaves showed that Fusarium sp.stress significantly reduced the content of total flavonoids,quercetin,isoquercitrin and isoquercitrin in C.oleifera leaves by 7.80%,50.00%and 75.90%,respectively.[Conclusions]Our results are an important step which showed strong resistance of C.oleifera and can give a novel insight for researches on the effects in the rhizosphere soil enzyme,soil nutrient elements and metabolites of C.oleifera under the Fusarium sp.too.
基金supports from the National ‘‘the eleventh-five years’’ Projects of Science and Technology under contract (No. D09-0109-06-004) of ChinaInnovative Team Program of Universities in Shanghai of Shanghai Municipality Education Commission (No. B-48-0109-09-002) of China
文摘This paper presents the model of calculating the total friction moment of space gyroscope ball bearings which usually work under ultra-low oscillatory motion and are very sensitive to the friction moment. The aim is to know the proportion of the friction moment caused by each frictional source in the bearing＇s total friction moment, which is helpful to optimize the bearing design to deduce the friction moment. In the model, the cage dynamic equations considering six degree-of-freedom and the balls dynamic equations considering two degree-of-freedom were solved.The good trends with different loads between the measured friction moments and computational results prove that the model under constant rate was validated. The computational results show that when the speed was set at 5 r/min, the bearing＇s maximum total friction moment when oscillation occurred was obviously larger than that occurred at a constant rate. At the onset of each oscillatory motion, the proportion of the friction moment caused by cage in the bearing＇s total friction moment was very high, and it increased with the increasing speed. The analyses of different cage thicknesses and different clearances between cage pocket and ball show that smaller thickness and clearance were preferred.
基金the National Natural Science Foundation of China(grant nos.51877216,52277229,and 22109178)Natural Science Foundation of Shandong Province(grant nos.ZR2020MB078,ZR2021QB085,and ZR2022MB094)+1 种基金National Key Research and Development of China(grant no.2022YFA1503400)Postdoctoral Innovative Talent Support Program of Shandong Province(grant no.SDBX2021005).
文摘Two-dimensional MXene-based film materials as flexible electrodes have been widely studied in wearable microsupercapacitors(MSCs).However,the existence of strong van derWaals interactions leads to serious self-stacking ofMXene layers,resulting in poor ionic dynamics and loss of active sites,which causes MXene film electrodes to exhibit low capacitance and poor rate performance in practical studies.To solve this,a frame-structured hybrid film(labeled as CN-MX hybrid film)is constructed by introducing intercalating agents(nanometer g-C_(3)N_(4))into MXene layers.In this unique hybrid film,the g-C_(3)N_(4)nanoparticles rationally occupy the interspace between MXene layers so as to alleviate layer stacking,thus effectively expanding the electrochemically active surface and promoting proton transfer.Synergistic pseudocapacitance inducted by g-C_(3)N_(4)surface groups,consequently,the CN-MX hybrid film electrode achieves an enhanced capacitive capability.In the three-electrode system,this frame-structured film electrode exhibits an ultra-high areal capacitance of 1932.8 mF cm^(−2).The assembled symmetry flexible MSC device based on CN-MX hybrid film can achieve an energy density of 2.28μWh cm^(−2)at 0.075 mW cm^(−2),as well as a superior cyclic stability with 90.4%retention after 700 cycles in alternating 90o bending and releasing states,revealing its potential in practical applications.
基金the financial support from the National Natural Science Foundation of China (Grant No. 51702361)the Natural Science Foundation of Hunan Province (Grant No. 2017JJ3353)
文摘Wave-transparent ceramic matrix composites for the high temperature use should possess excellent oxidation resistance. In this work, Si3N4f/SiO2 composites with different fiber content were fabricated by filament winding and sol gel method. The oxidation resistance was investigated by tracking the response of flexural strength to the testing temperature. The results show that the flexural strength and toughness of the composites with fiber content of over 37% can reach high levels at around 175.0 MPa and 6.2 MPa m^1/2, respectively. After 1 h oxidation at 1100℃, the flexural strength drops a lot but can still reach 114.4 MPa, which is high enough to ensure the safety of structures. However, when the oxidation temperature rises to 1200–1400℃, the flexural strengths continue to fall to a relatively low level at 50.0–66.4 MPa. The degradation at high temperatures is caused by the combination of over strong interfacial bonding, the damage of fiber and the crystallization of silica matrix.
文摘This paper reports a method for strand tension in anchor spans considering rotation.A kind of co-moved coordinate system,a saddle local coordinate system,was set up.This system implemented the rotation of the splay saddle through the rotation of the coordinate system,and all calculations proceeded in this coordinate system.Considering the rotation of the anchoring surface by the rotation of the local coordinate system of the anchoring surface,the anchorage point coordinates of strands were transformed to the local sadle coordinate system.There was a two-layer iteration adopted in the calculation.In the inner iteration,the cable force at the end of the vertical bend was taken as the variable,and the ordinate of the anchorage point was taken as the target value.In the outer iteration,the vertical tangential angle at the end of the vertical bend was taken as the variable,and the ordinate of the anchorage point was taken as the target value.The method carried out the rotation of the splay saddle and anchor surface and was simple,convenient and without approximation.The effect of rotation was considered precisely;it showed stability during the process of two-layer iteration,powerful adaptation and higher efficiency and had been successfully applied in the construction control of the Wufengshan Yangtze River Bridge,the world's first kilometer-level combined highway and railway suspension bridge.
基金the Fujian Agriculture and Forestry University Project for Technological Innovation of Tea Industry Chain and Service System Construction,the Fujian Province“2011 Collaborative Innovation Center”the Chinese Oolong Tea In dustry Innovati on Center special project(J2015-75)+1 种基金the Scientific Research Foundation of Graduate School of Fujian Agriculture and Forestry University(324-1122yb060)the Scientific Research Foundation of Horticulture College of Fujian Agriculture and Forestry University(2018B02).
文摘Plants have evolved regulatory mechanisms at multiple levels to regulate gene expression in order to improve their cold adaptability.However,limited information is available regarding the stress response at the chromatin and translational levels.Here,we characterize the chromatin accessibility,transcriptional,and translational landscapes of tea plants in vivo under chilling stress for the first time.Chilling stress signi ficantly affected both the transcription and translation levels as well as the translation efficiency of tea plants.A total of 3010 genes that underwent rapid and independent translation under chilling stress were observed,and they were signi ficantly enriched in the photosynthesis-antenna protein and phenylpropanoid biosynthesis pathways.A set of genes that were signi ficantly responsive to cold at the transcription and translation levels,including four(+)-neomenthol dehydrogenases(MNDs)and two(E)-nerolidol synthases(NESs)arranged in tandem on the chromosomes,were also found.We detected potential upstream open reading frames(uORFs)on 3082 genes and found that tea plants may inhibit the overall expression of genes by enhancing the translation of uORFs under chilling stress.In addition,we identi fied distal transposase hypersensitive sites(THSs)and proximal THSs and constructed a transcriptional regulatory network for tea plants under chilling stress.We also identi fied 13 high-con fidence transcription factors(TFs)that may play a crucial role in cold regulation.These results provide valuable information regarding the potential transcriptional regulatory network in plants and help to clarify how plants exhibit flexible responses to chilling stress.
