Zinc ion hybrid capacitors(ZIHCs), which integrate the features of the high power of supercapacitors and the high energy of zinc ion batteries, are promising competitors in future electrochemical energy storage applic...Zinc ion hybrid capacitors(ZIHCs), which integrate the features of the high power of supercapacitors and the high energy of zinc ion batteries, are promising competitors in future electrochemical energy storage applications. Carbon-based materials are deemed the competitive candidates for cathodes of ZIHC due to their cost-effectiveness, high electronic conductivity, chemical inertness, controllable surface states, and tunable pore architectures. In recent years, great research efforts have been devoted to further improving the energy density and cycling stability of ZIHCs. Reasonable modification and optimization of carbon-based materials offer a remedy for these challenges. In this review, the structural design, and electrochemical properties of carbon-based cathode materials with different dimensions, as well as the selection of compatible, robust current collectors and separators for ZIHCs are discussed. The challenges and prospects of ZIHCs are showcased to guide the innovative development of carbon-based cathode materials and the development of novel ZIHCs.展开更多
Amorphous carbons are promising anodes for high-rate potassium-ion batteries.Most low-temperature annealed amorphous carbons display unsatisfactory capacities.Heteroatom-induced defect engineering of amorphous carbons...Amorphous carbons are promising anodes for high-rate potassium-ion batteries.Most low-temperature annealed amorphous carbons display unsatisfactory capacities.Heteroatom-induced defect engineering of amorphous carbons could enhance their reversible capacities.Nevertheless,most lignocellulose biomasses lack heteroatoms,making it a challenge to design highly heteroatom-doped carbons(>10 at%).Herein,we report a new preparation strategy for amorphous carbon anodes.Nitrogen/sulfur co-doped lignin-derived porous carbons(NSLPC)with ultra-high nitrogen doping levels(21.6 at%of N and 0.8 at%of S)from renewable lignin biomacromolecule precursors were prepared through a supramolecule-mediated pyrolysis strategy.This supermolecule/lignin composite decomposes forming a covalently bonded graphitic carbon/amorphous carbon intermediate product,which induces the formation of high heteroatom doping in the obtained NSLPC.This unique pyrolysis chemistry and high heteroatom doping of NSLPC enable abundant defective active sites for the adsorption of K+and improved kinetics.The NSLPC anode delivered a high reversible capacity of 419 mAh g^(-1)and superior cycling stability(capacity retention of 96.6%at 1 A g^(-1)for 1000 cycles).Potassiumion hybrid capacitors assembled by NSLPC anode exhibited excellent cycling stability(91%capacity retention for 2000 cycles)and a high energy density of 71 Wh kg^(-1)at a power density of 92 W kg^(-1).展开更多
Molybdenum nickel alloy has been proved to be an efficient noble-metal-free catalyst for hydrogen evolution reaction(HER) in alkaline medium, but its electrocatalytic activity and stability need to be further improved...Molybdenum nickel alloy has been proved to be an efficient noble-metal-free catalyst for hydrogen evolution reaction(HER) in alkaline medium, but its electrocatalytic activity and stability need to be further improved to meet industrial requirements. In this study, carboxymethylated enzymatic hydrolysis lignin(EHL) was used as a biomacromolecule frame to coordinate with transition metal ions and reduced by pyrolysis to obtain the MoNi_(4)-NiO heterojunction(MoNi_(4)-NiO/C). The oblate sphere structure of MoNi_(4)-NiO/C exposed a large catalytic active surface to the electrolyte. As a result, the hydrogen evolution reaction of MoNi_(4)-NiO/C displayed a low overpotentials of 41 mV to achieve 10 mA cm-2and excellent stability of 100 h at 100 mA cm^(-2)in 1 mol L^(-1)KOH, which was superior to that of commercial Pt/C. Lignin assisted the formation of NiO to construct the MoNi_(4)-NiO interface and MoNi_(4)-NiO heterojunction structure, which reduced the energy barrier by forming a more favorable transition states and then promoted the formation of adsorbed hydrogen at the heterojunction interface through water dissociation in alkaline media, leading to the rapid reaction kinetics. This work provided an effective strategy for improving the electrocatalytic performance of noble-metal-free electrocatalysts encapsulated by lignin-derived carbon.展开更多
β-mercaptoethanol can induce adult adipose-derived stromal cells to rapidly and efficiently differentiate into typical neuron-like cells in vitro.Immunohistochemistry showed that neuron specific enolase and neurofila...β-mercaptoethanol can induce adult adipose-derived stromal cells to rapidly and efficiently differentiate into typical neuron-like cells in vitro.Immunohistochemistry showed that neuron specific enolase and neurofilament-200 expression gradually increased with the extension of induction time,and peaked at 5 hours.By contrast,glial fibrillary acidic protein was negatively expressed at all time points.Induced cells possessed a typical Nissl body,apoptosis showing condensed chromatin in the nucleus,autophagosomes with a bilayered membrane and autolysosomes in the cytoplasm at 5 hours.TUNEL assay and immunohistochemistry and immunofluorescence demonstrated that apoptosis and caspase-3 expression increased and peaked at 8 hours.Immunohistochemistry and immunofluorescence showed that microtubule-associated protein light chain 3 gradually increased with induction and reached a peak at 5 hours.These results indicate that autophagy played an important role in protecting cells during adult adipose-derived stromal cells differentiation into neuron-like cells in vitro.展开更多
A novel C/Pb composite has been successfully prepared by electroless plating to reduce the hydrogen evolution and achieve the high reversibility of the anode of lead-carbon battery(LCB). The deposited lead on the surf...A novel C/Pb composite has been successfully prepared by electroless plating to reduce the hydrogen evolution and achieve the high reversibility of the anode of lead-carbon battery(LCB). The deposited lead on the surface of C/Pb composite was found to be uniform and adherent to carbon surface. Because lead has been stuck on the surface of C/Pb composite, the embedded structure suppresses the hydrogen evolution of lead-carbon anode and strengthens the connection between carbon additive and sponge lead.Compared with the blank anode, the lead-carbon anode with C/Pb composite displays excellent charge—discharge reversibility, which is attributed to the good connection between carbon additives and lead that has been stuck on the surface of C/Pb composite during the preparation process. The addition of C/Pb composite maintains a solid anode structure with high specific surface area and power volume, and thereby, it plays a significant role in the highly reversible lead-carbon anode.展开更多
It is important to study the dilatancy property of water-saturated rock for understanding the engineering behavior of loaded rock mass. This study carried out the uniaxial and triaxial compressive experiments on the w...It is important to study the dilatancy property of water-saturated rock for understanding the engineering behavior of loaded rock mass. This study carried out the uniaxial and triaxial compressive experiments on the water-saturated red sandstone, analyzed the influences of confining pressure and pore pressure on dilatancy property of water-saturated rock, and discussed the reasonable basis of the stress of dilatancy onset as a strength design parameter of rock engineering, finally established the prediction model of the stress of dilatancy onset under the impacts of confining pressure and pore pressure. The results show that the strength parameters(the stress of dilatancy onset and peak strength) and deformation parameters(axial strain and circumferential strain) of water-saturated sandstone increase with the confining pressure, and the relations can be fitted with a positive linear function. The cohesion and internal friction angle obtained from the stress of dilatancy onset decrease by 11.57% and 7.33%, respectively, when compared with those obtained from the peak strength. The strength parameters and deformation parameters of water-saturated sandstone decrease basically with the increase of pore pressure, in which the relations between strength parameters or axial strain and pore pressure can be fitted with a negative linear function. However, the relation between the peak circumferential strain and the pore pressure should be characterized by a negative exponential function, and the circumferential strain at dilatancy onset isn't affected by the pore pressure.展开更多
A field campaign was carried out to investigate continuous diel methane(CH_4) flux from a subtropical eutrophic pond in November 2016. The diffusive methane flux of a single measurement had a range from2.68 9 10-5 to ...A field campaign was carried out to investigate continuous diel methane(CH_4) flux from a subtropical eutrophic pond in November 2016. The diffusive methane flux of a single measurement had a range from2.68 9 10-5 to 0.028 mmol·m^(-2)·h^(-1) with an average of0.011 ± 0.005 mmol·m^(-2)·h^(-1). The diffusive methane flux of measurements from 9:00 to 10:30 and from 21:00 to22:30 were very close to the average diffusive flux of all measurements. The bubble methane flux at different time measurements had much more variability than the diffusive methane flux. The bubble methane flux of a single measurement had a range from 0 to 0.312 mmol·m^(-2)·h^(-1) with an average of 0.024 ± 0.054 mmol·m^(-2)·h^(-1). For the eutrophic pond, the average bubble and diffusive CH_4 flux were 0.56 ± 0.18 and 0.26 ± 0.04 mmol·m^(-2)·day^(-1),respectively, and the CH_4 ebullition flux accounted for68.23% of the total flux. The maximum of the bubble CH_4 flux was about 4.6 times of the minimum CH_4 ebullition.The maximum of diffusive CH_4 flux was * 1.7 times of the corresponding minimum. The diffusive methane fluxes in daytime and nighttime were almost equal. However, the bubble methane flux in daytime was 0.029 mmol·m^(-2)·h^(-1),which was 1.6 times of that at night. Wind speed, thesurface water temperature, and DO dominate methane effluxes from the pond, and the latter is in nature subjected to the metabolism of algae in the pond. However, key environmental factors which dominate gas flux processes vary with different weather conditions. Wind speed is unimportant when it is extremely low.展开更多
Previous studies have demonstrated that nerve cells differentiated from adipose-derived stromal cells after chemical induction have reduced viability;however,the underlying mechanisms remained unclear.In this study,we...Previous studies have demonstrated that nerve cells differentiated from adipose-derived stromal cells after chemical induction have reduced viability;however,the underlying mechanisms remained unclear.In this study,we induced the differentiation of adult adipose-derived stromal cells into astrocytes using chemical induction.3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and flow cytometry showed that,with increasing induction time,the apoptotic rate gradually increased,and the number of living cells gradually decreased.Immunohistochemical staining demonstrated that the number of glial fibrillary acidic protein-,caspase-3-and caspase-9-positive cells gradually increased with increasing induction time.Transmission electron microscopy revealed typical signs of apoptosis after differentiation.Taken together,our results indicate that caspase-dependent apoptosis is an obstacle to the differentiation of adipose-derived stromal cells into astrocytes.Inhibiting apoptosis may be an important strategy for increasing the efficiency of induction.展开更多
Fruit detection and counting are essential tasks for horticulture research.With computer vision technology development,fruit detection techniques based on deep learning have been widely used in modern orchards.However...Fruit detection and counting are essential tasks for horticulture research.With computer vision technology development,fruit detection techniques based on deep learning have been widely used in modern orchards.However,most deep learning-based fruit detection models are generated based on fully supervised approaches,which means a model trained with one domain species may not be transferred to another.There is always a need to recreate and label the relevant training dataset,but such a procedure is time-consuming and labor-intensive.This paper proposed a domain adaptation method that can transfer an existing model trained from one domain to a new domain without extra manual labeling.The method includes three main steps:transform the source fruit image(with labeled information)into the target fruit image(without labeled information)through the CycleGAN network;Automatically label the target fruit image by a pseudo-label process;Improve the labeling accuracy by a pseudo-label self-learning approach.Use a labeled orange image dataset as the source domain,unlabeled apple and tomato image dataset as the target domain,the performance of the proposed method from the perspective of fruit detection has been evaluated.Without manual labeling for target domain image,the mean average precision reached 87.5%for apple detection and 76.9%for tomato detection,which shows that the proposed method can potentially fill the species gap in deep learning-based fruit detection.展开更多
Objective:Circulating cell-free Epstein-Barr virus(EBV)DNA has been shown to be a valuable biomarker for population screening and prognostic surveillance for nasopharyngeal carcinoma(NPC).Despite important insights in...Objective:Circulating cell-free Epstein-Barr virus(EBV)DNA has been shown to be a valuable biomarker for population screening and prognostic surveillance for nasopharyngeal carcinoma(NPC).Despite important insights into the biology of persistence,few studies have addressed the clinical significance of cell-based EBV-DNA loads in peripheral blood cells(PBCs).Methods:A prospective observational cohort study was conducted involving 1,063 newly diagnosed,locoregionally-advanced NPC patients at Sun Yat-sen University Cancer Center from 2005 to 2007.Cox regression analysis was conducted to identify the association of PBC EBV DNA loads to overall survival(OS)and other prognostic outcomes.Prognostic nomograms were developed based on PBC EBV DNA loads to predict survival outcomes for NPC patients.Results:After a median follow-up of 108 months,patients with higher PBC EBV-DNA loads had significantly worse OS[hazard ratio(HR)of medium,medium-high,and high vs.low were 1.50,1.52,and 1.85 respectively;Ptrend<0.001].Similar results were found for progression-free survival and distant metastasis-free survival.The concordance index of the prognostic nomogram for predicting OS in the training set and validation set were 0.70 and 0.66,respectively.Our data showed that the PBC EBV DNA load was an independent and robust survival biomarker,which remained significant even after adjusting for plasma EBV DNA loads in a subset of 205 patients of the cohort(HR:1.88;P=0.025).Importantly,a combination of PBC EBV DNA load and plasma EBV DNA load improved the predicted OS.Conclusions:The EBV-DNA load in PBCs may be an independent prognosis marker for NPC patients.展开更多
Several p H-dependent processes and reactions take place in the human body;hence,the p H of body fluids is the best indicator of disturbed health conditions.However,accurate and real-time diagnosis of the p H of body ...Several p H-dependent processes and reactions take place in the human body;hence,the p H of body fluids is the best indicator of disturbed health conditions.However,accurate and real-time diagnosis of the p H of body fluids is complicated because of limited commercially available p H sensors.Hence,we aimed to prepare a flexible,transparent,disposable,userfriendly,and economic strip-based solid-state p H sensor using palladium nanoparticles(Pd NPs)/N-doped carbon(NC)composite material.The Pd NPs/NC composite material was synthesized using wool keratin(WK)as a precursor.The insitu prepared Pd NPs played a key role in the controlled switching of protein structure to the N-doped carbon skeleton withπ–πarrangement at the mesoscale level,which mimics the A–B type polymeric structure,and hence,is highly susceptible to H+ions.The optimized carbonization condition in the presence of Pd NPs showed that the material obtained using a modified Ag/Ag Cl reference electrode had the highest p H sensitivity with excellent stability and durability.The optimized p H sensor showed high specificity and selectivity with a sensitivity of 55 m V/p H unit and a relative standard deviation of 0.79%.This study is the first to synthesize Pd NPs using WK as a stabilizing and reducing agent.The applicability of the sensor was investigated for biological samples,namely,saliva and gastric juices.The proposed protocol and material have implications in solid-state chemistry,where biological material will be the best choice for the synthesis of materials with anticipated performance.展开更多
The circum-lake zone of the Qinghai Lake is one of the most serious regions of desertification on the Qinghai-Tibetan Plateau. Based on Remote Sensing(RS) and Geographical Information System(GIS) techniques, the four ...The circum-lake zone of the Qinghai Lake is one of the most serious regions of desertification on the Qinghai-Tibetan Plateau. Based on Remote Sensing(RS) and Geographical Information System(GIS) techniques, the four sets of remote sensing images acquired in 1976, 1987, 1995, and 2006 were selected to conduct thematic information extraction in 14,300 km2 of land in the circum-lake zone using the Earth Resource Data Analysis System(ERDAS) image and information processing function. In the meantime the off-site interpretation and filed check-correction methods were used to reconstruct the temporal-spatial dynamic changes and differentiation patterns of land desertification in the circum-lake zone in the past 30 years, and based on this, the developmental trend of land desertification in the next 20 years was predicted. The results of the study show that in the past 30 years land desertification in the region experienced a continuous fluctuation between rapid- and slow-development processes in time, while in space it exhibited a few small patchy distributions or sporadic distributions in many places while at the same time, four large sand-dominated distributions stood out and evolved into a circum-lake belt differentiation pattern with a lakeside dike as the connecting line. Due to the integrated effects of climate changes, human activities and artificial rehabilitation, land desertification area in the region in the next 20 years will exhibit an increasing trend in the first 15 years and then increase at a slower rate, and afterward occur in a reverse, decreasing trend.展开更多
In the present study, we developed silicosis of rat model by bronchial perfusion SiO2 dust, and intervenes with AcSDKP, immunohisto chemistry was used to detect NF-κb and MCP-1 expression in lung tissue, and positive...In the present study, we developed silicosis of rat model by bronchial perfusion SiO2 dust, and intervenes with AcSDKP, immunohisto chemistry was used to detect NF-κb and MCP-1 expression in lung tissue, and positive cells were counted. We found that compared with silicotic model group, the positive cells of NF-κb and MCP-1 were decreased significantly in anti-fibrosis treatment of AcSDKP group. The findings suggest that AcSDKP could inhibit the expression of NF-κb and MCP-1 in lung tissue of silicosos, this may be related to AcSDKP inhibit of macrophage infiltration in lung tissue and reduced the degree of dust alveolitis.展开更多
Biomass-derived carbon materials for lithiumion batteries emerge as one of the most promising anodes from sustainable perspective.However,improving the reversible capacity and cycling performance remains a long-standi...Biomass-derived carbon materials for lithiumion batteries emerge as one of the most promising anodes from sustainable perspective.However,improving the reversible capacity and cycling performance remains a long-standing challenge.By combining the benefits of K2CO_(3) activation and KMnO_(4) hydrothermal treatment,this work proposes a two-step activation method to load MnO_(2) charge transfer onto biomass-derived carbon(KAC@MnO_(2)).Comprehensive analysis reveals that KAC@MnO_(2) has a micro-mesoporous coexistence structure and uniform surface distribution of MnO_(2),thus providing an improved electrochemical performance.Specifically,KAC@MnO_(2) exhibits an initial chargedischarge capacity of 847.3/1813.2 mAh·g^(-1) at 0.2 A·g^(-1),which is significantly higher than that of direct pyrolysis carbon and K2CO_(3) activated carbon,respectively.Furthermore,the KAC@MnO_(2) maintains a reversible capacity of 652.6 mAh·g^(-1) after 100 cycles.Even at a high current density of 1.0 A·g^(-1),KAC@MnO_(2) still exhibits excellent long-term cycling stability and maintains a stable reversible capacity of 306.7 mAh·g^(-1) after 500 cycles.Compared with reported biochar anode materials,the KAC@MnO_(2) prepared in this work shows superior reversible capacity and cycling performance.Additionally,the Li+insertion and de-insertion mechanisms are verified by ex situ X-ray diffraction analysis during the chargedischarge process,helping us better understand the energy storage mechanism of KAC@MnO_(2).展开更多
The widespread implementation of supercapacitors is hindered by the limited energy density and the pricey porous carbon electrode materials.The cost of porous carbon is a significant factor in the overall cost of supe...The widespread implementation of supercapacitors is hindered by the limited energy density and the pricey porous carbon electrode materials.The cost of porous carbon is a significant factor in the overall cost of supercapacitors,therefore a high carbon yield could effectively mitigate the production cost of porous carbon.This study proposes a method to produce porous carbon spheres through a spray drying technique combined with a carbonization process,utilizing renewable enzymatic hydrolysis lignin as the carbon source and KOH as the activation agent.The purpose of this study is to examine the relationship between the quantity of activation agent and the development of morphology,pore structure,and specific surface area of the obtained porous carbon materials.We demonstrate that this approach significantly enhances the carbon yield of porous carbon,achieving a yield of 22%in contrast to the conventional carbonization-activation method(9%).The samples acquired through this method were found to contain a substantial amount of mesopores,with an average pore size of 1.59 to 1.85 nm and a mesopore ratio of 25.6%.Additionally,these samples showed high specific surface areas,ranging from 1051 to 1831 m2·g^(−1).Zinc ion hybrid capacitors with lignin-derived porous carbon cathode exhibited a high capacitance of 279 F·g^(−1) at 0.1 A·g^(−1) and an energy density of 99.1 Wh·kg^(−1) when the power density was 80 kW·kg^(−1).This research presents a novel approach for producing porous carbons with high yield through the utilization of a spray drying approach.展开更多
Lithium-ion batteries are widely used in portable electronics and electric vehicles due to their high energy density,stable cycle life,and low self-discharge.However,irreversible lithium loss during the formation of t...Lithium-ion batteries are widely used in portable electronics and electric vehicles due to their high energy density,stable cycle life,and low self-discharge.However,irreversible lithium loss during the formation of the solid electrolyte interface greatly impairs energy density and cyclability.To compensate for the lithium loss,introducing an external lithium source,that is,a prelithiation agent,is an effective strategy to solve the above problems.Compared with other prelithiation strategies,cathode prelithiation is more cost-effective with simpler operation.Among various cathode prelithiation agents,we first systematically summarize the recent progress of Li_(2)S-based prelithiation agents,and then propose some novel strategies to tackle the current challenges.This review provides a comprehensive understanding of Li_(2)S-based prelithiation agents and new research directions in the future.展开更多
Dasypyrum villosum is one of the most valuable gene resources in wheat improvement,especially for disease resistance.The mining of favorable genes from D.villosum is frustrated by the lack of a whole genome sequence.I...Dasypyrum villosum is one of the most valuable gene resources in wheat improvement,especially for disease resistance.The mining of favorable genes from D.villosum is frustrated by the lack of a whole genome sequence.In this study,we generated a doubled-haploid line,91C43^(DH),using microspore culture and obtained a 4.05-GB high-quality,chromosome-scale genome assembly for D.villosum.The assembly contains39727 high-confidence genes,and 85.31% of the sequences are repetitive.Two reciprocal translocation events were detected,and 7VS-4VL is a unique translocation in D.villosum.The prolamin seed storage protein-coding genes were found to be duplicated;in particular,the genes encoding low-molecular-weight glutenin at the Glu-V3 locus were significantly expanded.RNA sequencing(RNA-seq)analysis indicated that,after Blumeria graminearum f.sp tritici(Bgt)inoculation,there were more upregulated genes involved in the pattern-triggered immunity and effector-triggered immunity defense pathways in D.villosum than in Triticum urartu.MNase hypersensitive sequencing(MH-seq)identified two Bgt-inducible MH sites(MHSs),one in the promoter and one in the 3'terminal region of the powdery mildew resistance(Pm)gene NLR1-V.Each site had two subpeaks and they were termed MHS1(MHS1.1/1.2)and MHS2(MHS2.1/2.2).Bgt-inducible MHS2.2 was uniquely present in D.villosum,and MHS1.1 was more inducible in D.villosum than in wheat,suggesting that MHSs may be critical for regulation of NLR1-V expression and plant defense.In summary,this study provides a valuable genome resource for functional genomics studies and wheat-D.villosum introgression breeding.The identified regulatory mechanisms may also be exploited to develop new strategies for enhancing Pm resistance by optimizing gene expression in wheat.展开更多
Nanoparticle-based therapeutics represent potential strategies for treating atherosclerosis;however,the complex plaque microenvironment poses a barrier for nanoparticles to target the dysfunctional cells.Here,we repor...Nanoparticle-based therapeutics represent potential strategies for treating atherosclerosis;however,the complex plaque microenvironment poses a barrier for nanoparticles to target the dysfunctional cells.Here,we report reactive oxygen species(ROS)-responsive and size-reducible nanoassemblies,formed by multivalent host-guest interactions betweenβ-cyclodextrins(β-CD)-anchored discoidal recombinant high-density lipoprotein(NP^(3)_(ST))and hyaluronic acid-ferrocene(HA-Fc)conjugates.The HA-Fc/NP^(3)_(ST)nanoassemblies have extended blood circulation time,specifically accumulate in atherosclerotic plaque mediated by the HA receptors CD44 highly expressed in injured endothelium,rapidly disassemble in response to excess ROS in the intimal and release smaller NP^(3)_(ST),allowing for further plaque penetration,macrophage-targeted cholesterol efflux and drug delivery.In vivo pharmacodynamicses in atherosclerotic mice shows that HA-Fc/NP^(3)_(ST)reduces plaque size by 53%,plaque lipid deposition by 63%,plaque macrophage content by 62%and local inflammatory factor level by 64%compared to the saline group.Meanwhile,HA-Fc/NP^(3)_(ST)alleviates systemic inflammation characterized by reduced serum inflammatory factor levels.Collectively,HA-Fc/NP^(3)_(ST)nanoassemblies with ROS-responsive and size-reducible properties exhibit a deeper penetration in atherosclerotic plaque and enhanced macrophage targeting ability,thus exerting effective cholesterol efflux and drug delivery for atherosclerosis therapy.展开更多
N-Acetylneuraminic acid(Neu5Ac),the most common type of Sia,generally acts as the terminal sugar in cell surface glycans,glycoconjugates,oligosaccharides,lipo-oligosaccharides,and polysaccharides,thus exerting numerou...N-Acetylneuraminic acid(Neu5Ac),the most common type of Sia,generally acts as the terminal sugar in cell surface glycans,glycoconjugates,oligosaccharides,lipo-oligosaccharides,and polysaccharides,thus exerting numerous physiological functions.The extensive applications of Neu5Ac in the food,cosmetic,and pharmaceutical industries make large-scale production of this chemical desirable.Biosynthesis which is associated with important application potential and environmental friendliness has become an indispensable approach for large-scale synthesis of Neu5Ac.In this review,the physiological roles of Neu5Ac was first summarized in detail.Second,the safety evaluation,regulatory status,and applications of Neu5Ac were discussed.Third,enzyme-catalyzed preparation,whole-cell biocatalysis,and microbial de novo synthesis of Neu5Ac were comprehensively reviewed.In addition,we discussed the main challenges of Neu5Ac de novo biosynthesis,such as screening and engineering of key enzymes,identifying exporters of intermediates and Neu5Ac,and balancing cell growth and biosynthesis.The corresponding strategies and systematic strategies were proposed to overcome these challenges and facilitate Neu5Ac industrial-scale production.展开更多
Dear Editor,Common wheat(Triticum aestivum,2n=6×=42,AABBDD)is the staple crop worldwide.Elucidating the gene regulatory network provides essential information for mechanism studies and targeted manipulation of ge...Dear Editor,Common wheat(Triticum aestivum,2n=6×=42,AABBDD)is the staple crop worldwide.Elucidating the gene regulatory network provides essential information for mechanism studies and targeted manipulation of gene activity for breeding.However,it is a challenging task given the extremely large(16 Gb)and complicated allohexaploid genome of common wheat.Integrating multi-omics data is a compelling approach to construct the hierarchical regulatory network.展开更多
基金the financial support from the National Natural Science Foundation of China (22108044)the 111 Project (B20088)+3 种基金the Fundamental Research Funds for the Central Universities (2572022DJ02)the Research and Development Program in Key Fields of Guangdong Province (2020B1111380002)the Basic Research and Applicable Basic Research in Guangzhou City (202201010290)the Guangdong Provincial Key Laboratory of Plant Resources Biorefinery (2021GDKLPRB07)。
文摘Zinc ion hybrid capacitors(ZIHCs), which integrate the features of the high power of supercapacitors and the high energy of zinc ion batteries, are promising competitors in future electrochemical energy storage applications. Carbon-based materials are deemed the competitive candidates for cathodes of ZIHC due to their cost-effectiveness, high electronic conductivity, chemical inertness, controllable surface states, and tunable pore architectures. In recent years, great research efforts have been devoted to further improving the energy density and cycling stability of ZIHCs. Reasonable modification and optimization of carbon-based materials offer a remedy for these challenges. In this review, the structural design, and electrochemical properties of carbon-based cathode materials with different dimensions, as well as the selection of compatible, robust current collectors and separators for ZIHCs are discussed. The challenges and prospects of ZIHCs are showcased to guide the innovative development of carbon-based cathode materials and the development of novel ZIHCs.
基金the financial support from the National Natural Science Foundation of China(22108044,22208061)the Research and Development Program in Key Fields of Guangdong Province(2020B1111380002)+1 种基金the Basic Research and Applicable Basic Research in Guangzhou City(202201010290)the financial support from the Guangdong Provincial Key Laboratory of Plant Resources Biorefinery(2021GDKLPRB07)。
文摘Amorphous carbons are promising anodes for high-rate potassium-ion batteries.Most low-temperature annealed amorphous carbons display unsatisfactory capacities.Heteroatom-induced defect engineering of amorphous carbons could enhance their reversible capacities.Nevertheless,most lignocellulose biomasses lack heteroatoms,making it a challenge to design highly heteroatom-doped carbons(>10 at%).Herein,we report a new preparation strategy for amorphous carbon anodes.Nitrogen/sulfur co-doped lignin-derived porous carbons(NSLPC)with ultra-high nitrogen doping levels(21.6 at%of N and 0.8 at%of S)from renewable lignin biomacromolecule precursors were prepared through a supramolecule-mediated pyrolysis strategy.This supermolecule/lignin composite decomposes forming a covalently bonded graphitic carbon/amorphous carbon intermediate product,which induces the formation of high heteroatom doping in the obtained NSLPC.This unique pyrolysis chemistry and high heteroatom doping of NSLPC enable abundant defective active sites for the adsorption of K+and improved kinetics.The NSLPC anode delivered a high reversible capacity of 419 mAh g^(-1)and superior cycling stability(capacity retention of 96.6%at 1 A g^(-1)for 1000 cycles).Potassiumion hybrid capacitors assembled by NSLPC anode exhibited excellent cycling stability(91%capacity retention for 2000 cycles)and a high energy density of 71 Wh kg^(-1)at a power density of 92 W kg^(-1).
基金the financial support of the National Natural Science Foundation of China (22038004, 22078069 and 22178069)the Guangdong Basic and Applied Basic Research Foundation (2019B151502038 and 2021A1515012354)+1 种基金Guangdong Provincial Key Research and Development Program (2020B1111380002)the Guangdong Provincial Key Laboratory of Plant Resources Biorefinery (2021GDKLPRB-K05)。
文摘Molybdenum nickel alloy has been proved to be an efficient noble-metal-free catalyst for hydrogen evolution reaction(HER) in alkaline medium, but its electrocatalytic activity and stability need to be further improved to meet industrial requirements. In this study, carboxymethylated enzymatic hydrolysis lignin(EHL) was used as a biomacromolecule frame to coordinate with transition metal ions and reduced by pyrolysis to obtain the MoNi_(4)-NiO heterojunction(MoNi_(4)-NiO/C). The oblate sphere structure of MoNi_(4)-NiO/C exposed a large catalytic active surface to the electrolyte. As a result, the hydrogen evolution reaction of MoNi_(4)-NiO/C displayed a low overpotentials of 41 mV to achieve 10 mA cm-2and excellent stability of 100 h at 100 mA cm^(-2)in 1 mol L^(-1)KOH, which was superior to that of commercial Pt/C. Lignin assisted the formation of NiO to construct the MoNi_(4)-NiO interface and MoNi_(4)-NiO heterojunction structure, which reduced the energy barrier by forming a more favorable transition states and then promoted the formation of adsorbed hydrogen at the heterojunction interface through water dissociation in alkaline media, leading to the rapid reaction kinetics. This work provided an effective strategy for improving the electrocatalytic performance of noble-metal-free electrocatalysts encapsulated by lignin-derived carbon.
文摘β-mercaptoethanol can induce adult adipose-derived stromal cells to rapidly and efficiently differentiate into typical neuron-like cells in vitro.Immunohistochemistry showed that neuron specific enolase and neurofilament-200 expression gradually increased with the extension of induction time,and peaked at 5 hours.By contrast,glial fibrillary acidic protein was negatively expressed at all time points.Induced cells possessed a typical Nissl body,apoptosis showing condensed chromatin in the nucleus,autophagosomes with a bilayered membrane and autolysosomes in the cytoplasm at 5 hours.TUNEL assay and immunohistochemistry and immunofluorescence demonstrated that apoptosis and caspase-3 expression increased and peaked at 8 hours.Immunohistochemistry and immunofluorescence showed that microtubule-associated protein light chain 3 gradually increased with induction and reached a peak at 5 hours.These results indicate that autophagy played an important role in protecting cells during adult adipose-derived stromal cells differentiation into neuron-like cells in vitro.
基金the financial support provided by the National Natural Science Foundation of China (No.21573093)the National Key Research and Development Program (No.2017YFB0307501)Guangdong Innovative and Entrepreneurial Research Team Program (No.2013C092)
文摘A novel C/Pb composite has been successfully prepared by electroless plating to reduce the hydrogen evolution and achieve the high reversibility of the anode of lead-carbon battery(LCB). The deposited lead on the surface of C/Pb composite was found to be uniform and adherent to carbon surface. Because lead has been stuck on the surface of C/Pb composite, the embedded structure suppresses the hydrogen evolution of lead-carbon anode and strengthens the connection between carbon additive and sponge lead.Compared with the blank anode, the lead-carbon anode with C/Pb composite displays excellent charge—discharge reversibility, which is attributed to the good connection between carbon additives and lead that has been stuck on the surface of C/Pb composite during the preparation process. The addition of C/Pb composite maintains a solid anode structure with high specific surface area and power volume, and thereby, it plays a significant role in the highly reversible lead-carbon anode.
基金supported by the National Natural Science Foundation of China (Nos. 51404266 and 11502229)the National Program on Key Basic Research Project of China (No. 2013CB227900)
文摘It is important to study the dilatancy property of water-saturated rock for understanding the engineering behavior of loaded rock mass. This study carried out the uniaxial and triaxial compressive experiments on the water-saturated red sandstone, analyzed the influences of confining pressure and pore pressure on dilatancy property of water-saturated rock, and discussed the reasonable basis of the stress of dilatancy onset as a strength design parameter of rock engineering, finally established the prediction model of the stress of dilatancy onset under the impacts of confining pressure and pore pressure. The results show that the strength parameters(the stress of dilatancy onset and peak strength) and deformation parameters(axial strain and circumferential strain) of water-saturated sandstone increase with the confining pressure, and the relations can be fitted with a positive linear function. The cohesion and internal friction angle obtained from the stress of dilatancy onset decrease by 11.57% and 7.33%, respectively, when compared with those obtained from the peak strength. The strength parameters and deformation parameters of water-saturated sandstone decrease basically with the increase of pore pressure, in which the relations between strength parameters or axial strain and pore pressure can be fitted with a negative linear function. However, the relation between the peak circumferential strain and the pore pressure should be characterized by a negative exponential function, and the circumferential strain at dilatancy onset isn't affected by the pore pressure.
基金financially supported by the National Science of China (Nos. 41273110, 91647207, and 51509086)Natural Science Foundation of Hubei Province, China (2014CFB672)
文摘A field campaign was carried out to investigate continuous diel methane(CH_4) flux from a subtropical eutrophic pond in November 2016. The diffusive methane flux of a single measurement had a range from2.68 9 10-5 to 0.028 mmol·m^(-2)·h^(-1) with an average of0.011 ± 0.005 mmol·m^(-2)·h^(-1). The diffusive methane flux of measurements from 9:00 to 10:30 and from 21:00 to22:30 were very close to the average diffusive flux of all measurements. The bubble methane flux at different time measurements had much more variability than the diffusive methane flux. The bubble methane flux of a single measurement had a range from 0 to 0.312 mmol·m^(-2)·h^(-1) with an average of 0.024 ± 0.054 mmol·m^(-2)·h^(-1). For the eutrophic pond, the average bubble and diffusive CH_4 flux were 0.56 ± 0.18 and 0.26 ± 0.04 mmol·m^(-2)·day^(-1),respectively, and the CH_4 ebullition flux accounted for68.23% of the total flux. The maximum of the bubble CH_4 flux was about 4.6 times of the minimum CH_4 ebullition.The maximum of diffusive CH_4 flux was * 1.7 times of the corresponding minimum. The diffusive methane fluxes in daytime and nighttime were almost equal. However, the bubble methane flux in daytime was 0.029 mmol·m^(-2)·h^(-1),which was 1.6 times of that at night. Wind speed, thesurface water temperature, and DO dominate methane effluxes from the pond, and the latter is in nature subjected to the metabolism of algae in the pond. However, key environmental factors which dominate gas flux processes vary with different weather conditions. Wind speed is unimportant when it is extremely low.
文摘Previous studies have demonstrated that nerve cells differentiated from adipose-derived stromal cells after chemical induction have reduced viability;however,the underlying mechanisms remained unclear.In this study,we induced the differentiation of adult adipose-derived stromal cells into astrocytes using chemical induction.3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and flow cytometry showed that,with increasing induction time,the apoptotic rate gradually increased,and the number of living cells gradually decreased.Immunohistochemical staining demonstrated that the number of glial fibrillary acidic protein-,caspase-3-and caspase-9-positive cells gradually increased with increasing induction time.Transmission electron microscopy revealed typical signs of apoptosis after differentiation.Taken together,our results indicate that caspase-dependent apoptosis is an obstacle to the differentiation of adipose-derived stromal cells into astrocytes.Inhibiting apoptosis may be an important strategy for increasing the efficiency of induction.
基金supported by National Natural Science Foundation of China(NSFC)program U19A2061Japan Science and Technology Agency(JST)CREST program JPMJCR1512,SICORP Program JPMJSC16H2 and aXis program JPMJAS2018.
文摘Fruit detection and counting are essential tasks for horticulture research.With computer vision technology development,fruit detection techniques based on deep learning have been widely used in modern orchards.However,most deep learning-based fruit detection models are generated based on fully supervised approaches,which means a model trained with one domain species may not be transferred to another.There is always a need to recreate and label the relevant training dataset,but such a procedure is time-consuming and labor-intensive.This paper proposed a domain adaptation method that can transfer an existing model trained from one domain to a new domain without extra manual labeling.The method includes three main steps:transform the source fruit image(with labeled information)into the target fruit image(without labeled information)through the CycleGAN network;Automatically label the target fruit image by a pseudo-label process;Improve the labeling accuracy by a pseudo-label self-learning approach.Use a labeled orange image dataset as the source domain,unlabeled apple and tomato image dataset as the target domain,the performance of the proposed method from the perspective of fruit detection has been evaluated.Without manual labeling for target domain image,the mean average precision reached 87.5%for apple detection and 76.9%for tomato detection,which shows that the proposed method can potentially fill the species gap in deep learning-based fruit detection.
基金supported by grants from the National Key Research and Development Program of China(Grant No.2016YFC0902001)the Sino-Sweden Joint Research Program(Grant No.81861138006)+5 种基金the Science and Technology Planning Project of Guangzhou,China(Grant No.201804020094)the National Natural Science Foundation of China(Grant Nos.81973131,81903395,81803319,and 81502056)the National Science Fund for Distinguished Young Scholars of China(Grant No.81325018)the Key Project for International Cooperation and Exchange of the National Natural Science Foundation of China(Grant No.81220108022)the Natural Science Foundation of Guangdong Province(Grant No.2017A030312003)。
文摘Objective:Circulating cell-free Epstein-Barr virus(EBV)DNA has been shown to be a valuable biomarker for population screening and prognostic surveillance for nasopharyngeal carcinoma(NPC).Despite important insights into the biology of persistence,few studies have addressed the clinical significance of cell-based EBV-DNA loads in peripheral blood cells(PBCs).Methods:A prospective observational cohort study was conducted involving 1,063 newly diagnosed,locoregionally-advanced NPC patients at Sun Yat-sen University Cancer Center from 2005 to 2007.Cox regression analysis was conducted to identify the association of PBC EBV DNA loads to overall survival(OS)and other prognostic outcomes.Prognostic nomograms were developed based on PBC EBV DNA loads to predict survival outcomes for NPC patients.Results:After a median follow-up of 108 months,patients with higher PBC EBV-DNA loads had significantly worse OS[hazard ratio(HR)of medium,medium-high,and high vs.low were 1.50,1.52,and 1.85 respectively;Ptrend<0.001].Similar results were found for progression-free survival and distant metastasis-free survival.The concordance index of the prognostic nomogram for predicting OS in the training set and validation set were 0.70 and 0.66,respectively.Our data showed that the PBC EBV DNA load was an independent and robust survival biomarker,which remained significant even after adjusting for plasma EBV DNA loads in a subset of 205 patients of the cohort(HR:1.88;P=0.025).Importantly,a combination of PBC EBV DNA load and plasma EBV DNA load improved the predicted OS.Conclusions:The EBV-DNA load in PBCs may be an independent prognosis marker for NPC patients.
基金supported by the National Natural Science Foundation of China(Grant Nos.51502253,U1405226,21503175,and 21705135)Natural Science Foundation of Guangdong Province,China(Grant No.2016A030310369)Natural Science Foundation of Fujian Province,China(Grant No.2017J01104)。
文摘Several p H-dependent processes and reactions take place in the human body;hence,the p H of body fluids is the best indicator of disturbed health conditions.However,accurate and real-time diagnosis of the p H of body fluids is complicated because of limited commercially available p H sensors.Hence,we aimed to prepare a flexible,transparent,disposable,userfriendly,and economic strip-based solid-state p H sensor using palladium nanoparticles(Pd NPs)/N-doped carbon(NC)composite material.The Pd NPs/NC composite material was synthesized using wool keratin(WK)as a precursor.The insitu prepared Pd NPs played a key role in the controlled switching of protein structure to the N-doped carbon skeleton withπ–πarrangement at the mesoscale level,which mimics the A–B type polymeric structure,and hence,is highly susceptible to H+ions.The optimized carbonization condition in the presence of Pd NPs showed that the material obtained using a modified Ag/Ag Cl reference electrode had the highest p H sensitivity with excellent stability and durability.The optimized p H sensor showed high specificity and selectivity with a sensitivity of 55 m V/p H unit and a relative standard deviation of 0.79%.This study is the first to synthesize Pd NPs using WK as a stabilizing and reducing agent.The applicability of the sensor was investigated for biological samples,namely,saliva and gastric juices.The proposed protocol and material have implications in solid-state chemistry,where biological material will be the best choice for the synthesis of materials with anticipated performance.
基金supported by National Natural Science Foundations of China (Grant Nos. 40761026 and 41161036)the grant of the Outstanding Youth Foundation Project Program of the Northwest Normal University (No. NWNU-LKON-10-34)
文摘The circum-lake zone of the Qinghai Lake is one of the most serious regions of desertification on the Qinghai-Tibetan Plateau. Based on Remote Sensing(RS) and Geographical Information System(GIS) techniques, the four sets of remote sensing images acquired in 1976, 1987, 1995, and 2006 were selected to conduct thematic information extraction in 14,300 km2 of land in the circum-lake zone using the Earth Resource Data Analysis System(ERDAS) image and information processing function. In the meantime the off-site interpretation and filed check-correction methods were used to reconstruct the temporal-spatial dynamic changes and differentiation patterns of land desertification in the circum-lake zone in the past 30 years, and based on this, the developmental trend of land desertification in the next 20 years was predicted. The results of the study show that in the past 30 years land desertification in the region experienced a continuous fluctuation between rapid- and slow-development processes in time, while in space it exhibited a few small patchy distributions or sporadic distributions in many places while at the same time, four large sand-dominated distributions stood out and evolved into a circum-lake belt differentiation pattern with a lakeside dike as the connecting line. Due to the integrated effects of climate changes, human activities and artificial rehabilitation, land desertification area in the region in the next 20 years will exhibit an increasing trend in the first 15 years and then increase at a slower rate, and afterward occur in a reverse, decreasing trend.
文摘In the present study, we developed silicosis of rat model by bronchial perfusion SiO2 dust, and intervenes with AcSDKP, immunohisto chemistry was used to detect NF-κb and MCP-1 expression in lung tissue, and positive cells were counted. We found that compared with silicotic model group, the positive cells of NF-κb and MCP-1 were decreased significantly in anti-fibrosis treatment of AcSDKP group. The findings suggest that AcSDKP could inhibit the expression of NF-κb and MCP-1 in lung tissue of silicosos, this may be related to AcSDKP inhibit of macrophage infiltration in lung tissue and reduced the degree of dust alveolitis.
基金supported by the National Natural Science Foundation of China(Grant No.22078278)Hunan Innovative Talent Project(Grant No.2022RC1111)+1 种基金the Key project of Hunan Provincial Education Department(Grant No.22A0131)the State Key Laboratory of Clean Energy Utilization(Open Fund Project No.ZJUCEU2021009).
文摘Biomass-derived carbon materials for lithiumion batteries emerge as one of the most promising anodes from sustainable perspective.However,improving the reversible capacity and cycling performance remains a long-standing challenge.By combining the benefits of K2CO_(3) activation and KMnO_(4) hydrothermal treatment,this work proposes a two-step activation method to load MnO_(2) charge transfer onto biomass-derived carbon(KAC@MnO_(2)).Comprehensive analysis reveals that KAC@MnO_(2) has a micro-mesoporous coexistence structure and uniform surface distribution of MnO_(2),thus providing an improved electrochemical performance.Specifically,KAC@MnO_(2) exhibits an initial chargedischarge capacity of 847.3/1813.2 mAh·g^(-1) at 0.2 A·g^(-1),which is significantly higher than that of direct pyrolysis carbon and K2CO_(3) activated carbon,respectively.Furthermore,the KAC@MnO_(2) maintains a reversible capacity of 652.6 mAh·g^(-1) after 100 cycles.Even at a high current density of 1.0 A·g^(-1),KAC@MnO_(2) still exhibits excellent long-term cycling stability and maintains a stable reversible capacity of 306.7 mAh·g^(-1) after 500 cycles.Compared with reported biochar anode materials,the KAC@MnO_(2) prepared in this work shows superior reversible capacity and cycling performance.Additionally,the Li+insertion and de-insertion mechanisms are verified by ex situ X-ray diffraction analysis during the chargedischarge process,helping us better understand the energy storage mechanism of KAC@MnO_(2).
基金support from the National Natural Science Foundation of China(Grant No.22108044)the Research and Development Program in Key Fields of Guangdong Province(Grant No.2020B1111380002)the Basic Research and Applicable Basic Research in Guangzhou City(Grant No.202201010290).
文摘The widespread implementation of supercapacitors is hindered by the limited energy density and the pricey porous carbon electrode materials.The cost of porous carbon is a significant factor in the overall cost of supercapacitors,therefore a high carbon yield could effectively mitigate the production cost of porous carbon.This study proposes a method to produce porous carbon spheres through a spray drying technique combined with a carbonization process,utilizing renewable enzymatic hydrolysis lignin as the carbon source and KOH as the activation agent.The purpose of this study is to examine the relationship between the quantity of activation agent and the development of morphology,pore structure,and specific surface area of the obtained porous carbon materials.We demonstrate that this approach significantly enhances the carbon yield of porous carbon,achieving a yield of 22%in contrast to the conventional carbonization-activation method(9%).The samples acquired through this method were found to contain a substantial amount of mesopores,with an average pore size of 1.59 to 1.85 nm and a mesopore ratio of 25.6%.Additionally,these samples showed high specific surface areas,ranging from 1051 to 1831 m2·g^(−1).Zinc ion hybrid capacitors with lignin-derived porous carbon cathode exhibited a high capacitance of 279 F·g^(−1) at 0.1 A·g^(−1) and an energy density of 99.1 Wh·kg^(−1) when the power density was 80 kW·kg^(−1).This research presents a novel approach for producing porous carbons with high yield through the utilization of a spray drying approach.
基金National Natural Science Foundation of China,Grant/Award Number:22002045Guangdong Basic and Applied Basic Research Foundation,Grant/Award Number:2023A1515030164+1 种基金Special Topics in Key Areas for Universities in Guangdong Province,Grant/Award Number:2023ZDZX3001Hong Kong Scholars Program 2022,Grant/Award Numbers:G-YZ5Y,XJ2022026。
文摘Lithium-ion batteries are widely used in portable electronics and electric vehicles due to their high energy density,stable cycle life,and low self-discharge.However,irreversible lithium loss during the formation of the solid electrolyte interface greatly impairs energy density and cyclability.To compensate for the lithium loss,introducing an external lithium source,that is,a prelithiation agent,is an effective strategy to solve the above problems.Compared with other prelithiation strategies,cathode prelithiation is more cost-effective with simpler operation.Among various cathode prelithiation agents,we first systematically summarize the recent progress of Li_(2)S-based prelithiation agents,and then propose some novel strategies to tackle the current challenges.This review provides a comprehensive understanding of Li_(2)S-based prelithiation agents and new research directions in the future.
基金financially supported by the National Key Agriculture Projects(NK2022060101)National Key Research and Development Program(2022YFF1002900,2020YFE0202900)+3 种基金the Fundamental Research Funds for the Central University(XUEKEN2022012)Jiangsu Provincial Key Research and Development Program(BE2021375,BE2022346)Seed Industry Revitalization Project of Jiangsu Province(JBGS2021006,2021013,2021047)Joint Research of Improved Wheat Variety of Anhui,and Jiangsu Agricultural Technology System(JATS)(JATS[2021]463,JATS[2022]464).
文摘Dasypyrum villosum is one of the most valuable gene resources in wheat improvement,especially for disease resistance.The mining of favorable genes from D.villosum is frustrated by the lack of a whole genome sequence.In this study,we generated a doubled-haploid line,91C43^(DH),using microspore culture and obtained a 4.05-GB high-quality,chromosome-scale genome assembly for D.villosum.The assembly contains39727 high-confidence genes,and 85.31% of the sequences are repetitive.Two reciprocal translocation events were detected,and 7VS-4VL is a unique translocation in D.villosum.The prolamin seed storage protein-coding genes were found to be duplicated;in particular,the genes encoding low-molecular-weight glutenin at the Glu-V3 locus were significantly expanded.RNA sequencing(RNA-seq)analysis indicated that,after Blumeria graminearum f.sp tritici(Bgt)inoculation,there were more upregulated genes involved in the pattern-triggered immunity and effector-triggered immunity defense pathways in D.villosum than in Triticum urartu.MNase hypersensitive sequencing(MH-seq)identified two Bgt-inducible MH sites(MHSs),one in the promoter and one in the 3'terminal region of the powdery mildew resistance(Pm)gene NLR1-V.Each site had two subpeaks and they were termed MHS1(MHS1.1/1.2)and MHS2(MHS2.1/2.2).Bgt-inducible MHS2.2 was uniquely present in D.villosum,and MHS1.1 was more inducible in D.villosum than in wheat,suggesting that MHSs may be critical for regulation of NLR1-V expression and plant defense.In summary,this study provides a valuable genome resource for functional genomics studies and wheat-D.villosum introgression breeding.The identified regulatory mechanisms may also be exploited to develop new strategies for enhancing Pm resistance by optimizing gene expression in wheat.
基金supported by grants from the National Natural Science Foundation of China(grant no.81773669,82073788)National Major Science and Technology Projects of China(grant no.2017YFA0205400).
文摘Nanoparticle-based therapeutics represent potential strategies for treating atherosclerosis;however,the complex plaque microenvironment poses a barrier for nanoparticles to target the dysfunctional cells.Here,we report reactive oxygen species(ROS)-responsive and size-reducible nanoassemblies,formed by multivalent host-guest interactions betweenβ-cyclodextrins(β-CD)-anchored discoidal recombinant high-density lipoprotein(NP^(3)_(ST))and hyaluronic acid-ferrocene(HA-Fc)conjugates.The HA-Fc/NP^(3)_(ST)nanoassemblies have extended blood circulation time,specifically accumulate in atherosclerotic plaque mediated by the HA receptors CD44 highly expressed in injured endothelium,rapidly disassemble in response to excess ROS in the intimal and release smaller NP^(3)_(ST),allowing for further plaque penetration,macrophage-targeted cholesterol efflux and drug delivery.In vivo pharmacodynamicses in atherosclerotic mice shows that HA-Fc/NP^(3)_(ST)reduces plaque size by 53%,plaque lipid deposition by 63%,plaque macrophage content by 62%and local inflammatory factor level by 64%compared to the saline group.Meanwhile,HA-Fc/NP^(3)_(ST)alleviates systemic inflammation characterized by reduced serum inflammatory factor levels.Collectively,HA-Fc/NP^(3)_(ST)nanoassemblies with ROS-responsive and size-reducible properties exhibit a deeper penetration in atherosclerotic plaque and enhanced macrophage targeting ability,thus exerting effective cholesterol efflux and drug delivery for atherosclerosis therapy.
基金the National Key R&D Program of China(No.2022YFC2104900)the National Natural Science Foundation of China(No.31922073).
文摘N-Acetylneuraminic acid(Neu5Ac),the most common type of Sia,generally acts as the terminal sugar in cell surface glycans,glycoconjugates,oligosaccharides,lipo-oligosaccharides,and polysaccharides,thus exerting numerous physiological functions.The extensive applications of Neu5Ac in the food,cosmetic,and pharmaceutical industries make large-scale production of this chemical desirable.Biosynthesis which is associated with important application potential and environmental friendliness has become an indispensable approach for large-scale synthesis of Neu5Ac.In this review,the physiological roles of Neu5Ac was first summarized in detail.Second,the safety evaluation,regulatory status,and applications of Neu5Ac were discussed.Third,enzyme-catalyzed preparation,whole-cell biocatalysis,and microbial de novo synthesis of Neu5Ac were comprehensively reviewed.In addition,we discussed the main challenges of Neu5Ac de novo biosynthesis,such as screening and engineering of key enzymes,identifying exporters of intermediates and Neu5Ac,and balancing cell growth and biosynthesis.The corresponding strategies and systematic strategies were proposed to overcome these challenges and facilitate Neu5Ac industrial-scale production.
基金supported by the National Science Fund for Excellent Young Scholars(32022012)National Natural Science Foundation of China(31921005)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB27010302)Seed Industry Revitalization Project of Jiangsu Province(JBGS[2021]006).
文摘Dear Editor,Common wheat(Triticum aestivum,2n=6×=42,AABBDD)is the staple crop worldwide.Elucidating the gene regulatory network provides essential information for mechanism studies and targeted manipulation of gene activity for breeding.However,it is a challenging task given the extremely large(16 Gb)and complicated allohexaploid genome of common wheat.Integrating multi-omics data is a compelling approach to construct the hierarchical regulatory network.
