Design and control of pressure-swing distillation(PSD) with different heat integration modes for the separation of methyl acetate/methanol azeotrope are explored using Aspen Plus and Aspen Dynamics. First, an optimum ...Design and control of pressure-swing distillation(PSD) with different heat integration modes for the separation of methyl acetate/methanol azeotrope are explored using Aspen Plus and Aspen Dynamics. First, an optimum steady-state separation configuration conditions are obtained via taking the total annual cost(TAC) or total reboiler heat duty as the objective functions. The results show that about 27.68% and 25.40% saving in TAC can be achieved by the PSD with full and partial heat integration compared to PSD without heat integration. Second,temperature control tray locations are obtained according to the sensitivity criterion and singular value decomposition(SVD) analysis and the single-end control structure is effective based on the feed composition sensitivity analysis. Finally, the comparison of dynamic controllability is made among various control structures for PSD with partial and full heat integration. It is shown that both control structures of composition/temperature cascade and pressure-compensated temperature have a good dynamic response performance for PSD with heat integration facing feed flowrate and composition disturbances. However, PSD with full heat integration performs the poor controllability despite of a little bit of economy.展开更多
Rapid and robust identification of bacteria is crucial for environmental monitoring and clinical diagnosis.Herein,a bioinspired interface-mediated multichannel sensor array was developed based on three-coloremitting a...Rapid and robust identification of bacteria is crucial for environmental monitoring and clinical diagnosis.Herein,a bioinspired interface-mediated multichannel sensor array was developed based on three-coloremitting antimicrobial functional carbon dots(FCDs)and concanavalin A doped polydopamine nanoparticles(Con A-PDA)for identification of bacteria.In this sensor,the fluorescence intensity of the three FCDs was quenched by the Con A-PDA.Upon addition different types of bacteria,the fluorescence intensity of the three FCDs was restored or further quenched.Recur to statistical analysis methods,it is employed to accurately discriminate 10 types of bacteria(including three probiotics and seven pathogenic bacteria)in natural water samples and human urine samples.The discrimination ability of the sensor array was highly enhanced via different competing binding of the FCDs and the bacteria toward Con A-PDA.The proposed array-based method offers a rapid,high-throughput,and reliable sensing platform for pathogen diagnosis in the field of environmental monitoring and clinical diagnosis.展开更多
In order to obtain qualitative and quantitative characteristics of leaf epidermal micromorphology and mesophyll structure to evaluate the responses ofElaeagnus angustifolia L. to different environmental factors, epide...In order to obtain qualitative and quantitative characteristics of leaf epidermal micromorphology and mesophyll structure to evaluate the responses ofElaeagnus angustifolia L. to different environmental factors, epidermal micromorphology was observed by scanning electron microscopy （SEM）, and mesophyll structure was studied by light microscopy （LM） and transmission electron microscopy （TEM）. Materials were selected from Linze County, Gansu Province （material A） and Qitai County, Xinjiang Uygur Autonomous Region （material B） of China. Results show that lamina thickness was higher in material A, with one layer of epidermal cells in both adaxial and abaxial surfaces, and epidermal cell radial length was significantly longer in the adaxial surface. E. angustifolia leaves are typically bifacial, with a higher ratio of palisade to spongy tissue in material A. The thickness of trichome layer of epidermis was thicker in material A. In contrast, cell wall and cuticular wax of the epidermal cells were thinner in material A than in material B. Chloroplast ultrastructure was different with the approximate spherical chloroplast containing numerous starch grains and osmiophilic granules in ma- terial A, while only the spindly chloroplast contained starch grains in material B. Multiple layers of peltate or stel- late-peltate trichomes occupied both leaf surfaces in material A and the abaxial surface in material B, while the adaxial surface of material B contained few trichomes. Stomata were not observed on the leaf surfaces in materials A and B by SEM because of trichome obstruction. Our results indicate that the leaf structure of E. angustifolia is closely correlated with environmental factors, and the combination of leaf epidermal micromorphology and mesophyll structure afford re- sistance to environmental stress.展开更多
Plant density and spatial distribution in artificial vegetation is obviously initialized at the planting stage. Plant dynamics and spatial pattern may change over time as the result of interactions between individual ...Plant density and spatial distribution in artificial vegetation is obviously initialized at the planting stage. Plant dynamics and spatial pattern may change over time as the result of interactions between individual plants and habitats, but whether it’s applied for desert shrubs in artificial sand-fixing regions remains unknown. Here we examined changes in plant density and distribution patterns of three shrubs(Artemisia ordosica Krasch, Caragana korshinskii Kom, and Hedysarum scoparium Fisch.) in different regions, which have been restored for 27, 32 and 50 years(R27, R32, R50), respectively. The vegetation analysis shows that A. ordosica was the dominated species across the 3 restoration regions. The density of A. ordosica and H. scoparium show a significant increase from R27 to R32, then decreased in R50. The density of C. korshinskii was low in R32 and R50, lower in R27. The variance-to-mean ratio(VMR) was used to characterize spatial distribution patterns to fit the observed densities of the three shrubs by frequency. A. ordosica and C. korshinskii both show significantly clumped distributions in three restoration regions. H. scoparium show a uniform distribution in R27 and R50, but a clumped distribution in R32. These results show that A. ordosica seems to be more adaptable in revegetated desert areas compared to C. korshinskii and H. scoparium. Pattern analysis suggests a successive replacement of C. korshinskii, which had low proportions of survived shrubs, by the dominant A. ordosica. This study contributes to the understanding of the distribution patterns of shrubs plants in revegetation projects in arid desert areas.展开更多
Reaumuria soongorica is a short woody shrub widely found in semi-arid areas of China. It can survive severe environ- mental stress including high salinity in its natural habitat. Thus, we investigated the involvement ...Reaumuria soongorica is a short woody shrub widely found in semi-arid areas of China. It can survive severe environ- mental stress including high salinity in its natural habitat. Thus, we investigated the involvement of anti-oxidative enzymes, photosynthetic pigments and flavonoid metabolism in the adaptation of R. soongorica to saline environments. R. soon- gorica was treated with 0, 100, 200 and 400 mM NaC1 solutions for 14 days. Soil salt content increased significantly by watering with high content of NaC1 solution, and no variation between 8 and 14 days during treatment. The levels ofpe- roxidation of lipid membranes （measured by malondialdehyde content） and the activities of three antioxidant enzymes （superoxide dismutase （SOD）, peroxidase （POD） and ascorbate peroxidase （APX）） increased under salt stress. Chlorophyll and carotenoid content decreased with increasing salt content. The ratio of Chl a/Chl b and carotenoid/Chl exhibited sig- nificant increase under 400 mM NaC1. However, total flavonoid and anthocyanin contents and key enzyme activities in the flavonoid pathway including phenylalanine ammonialyase （PAL） and Chalcone isomerase （CHI） decreased under salt stress. These findings possibly suggest that R. soongorica has an adaptation protection mechanism against salt-induced oxidative damage by inducin~ the activity of antioxidant enzymes and maintaining a steady level of carotenoid/Chl.展开更多
Rapid and accurate diagnosis of oral cancer aggressiveness is associated with preoperative guidance and postoperative treatment.However,traditional diagnostic methods are time-consuming and easily misdiagnosed,which m...Rapid and accurate diagnosis of oral cancer aggressiveness is associated with preoperative guidance and postoperative treatment.However,traditional diagnostic methods are time-consuming and easily misdiagnosed,which makes it challenging to achieve high-precision classification.Herein,we introduce a recognition engineering-mediated multichannel nanosensor for the analysis of tumor metabolites,allowing for sensitive and rapid in vitro and intraoperative cancer malignancy discrimination.This nanosensor system utilizes engineered carbon dots(CDs)with various ratios of amino and carboxyl functional groups,assembled as a“shell”on gold nanoparticles(AuNPs).The multichannel nanosensor displayed distinct fingerprint patterns for fourteen tumor metabolites such as amino acids,nucleic acids,and other metabolites.It offers rapid“turn-on”fluorescence-encoded profiling,generating unique signatures for cancer malignancy within 15 min.The nanosensor demonstrated 100%accuracy in identifying the oral squamous cell carcinoma(OSCC)subtype and assessing malignancy levels.It will provide detailed pathology for the identification of clinical cancer tissue samples,including cancer cell subtype and differentiation grade.Together,our study highlights the potential of the fluorescent-encoded multichannel nanosensor as a powerful in vitro and intraoperative diagnostic tool for cancer malignancy and treatment guidance in advanced clinical oncology.展开更多
Single-atom nanozymes(SANzymes)with multi-mimetic activities capable of altering the cellular redox balance demonstrate significant potential in tumor therapy.However,the catalytic treatment provided by SANzymes alone...Single-atom nanozymes(SANzymes)with multi-mimetic activities capable of altering the cellular redox balance demonstrate significant potential in tumor therapy.However,the catalytic treatment provided by SANzymes alone is insufficient to achieve optimal outcomes.Therefore,the combination of nanozyme catalysis with drug therapy is considered a promising alternative.Nonetheless,the leakage of drug molecules is a primary cause of chemotherapy resistance in cancer treatment.Consequently,developing novel drug immobilization methods to attach them to SANzymes is expected to enable multimodal synergistic therapy.Herein,a multifunctional nanoplatform is designed by modifying bioinspired PDA on iron-based SANzyme(Fe SANzyme)and immobilizing doxorubicin(DOX)through Michael addition/Schiff base reaction,which greatly promotes the drug loading efficiency.The Fe SAN-PDA@DOX@HA displays controllable drugs release behavior in the tumor microenvironment(TME),where the Fe SAN-PDA nanozyme can catalyze high level of H_(2)O_(2)to produce oxygen to alleviate hypoxia,convert H_(2)O_(2)to the toxic reactive oxygen species(ROS),and deplete intracellular glutathione via the catalase(CAT),peroxidase(POD),and glutathione oxidase(GSHOx)-like activities,respectively.The high drug loading,exceptional nanozyme catalysis,combined with the good photothermal performance of Fe SAN-PDA,resulted in sustained chemodynamic/photothermal/chemotherapy in a mouse mammary carcinoma model.The results reveal the synergistic antitumor potential of the novel conjugation of DOX on Fe SANzyme via PDA,offering a strategy for drug immobilization,TME remodeling and synergistic multimodal therapy.展开更多
The gut microbiota and the associated metabolism play a pivotal role in maintaining human health,yet their assessment is challenging due to their inherent diversity,variety,and complexity.Herein,we developed a multich...The gut microbiota and the associated metabolism play a pivotal role in maintaining human health,yet their assessment is challenging due to their inherent diversity,variety,and complexity.Herein,we developed a multichannel sensor array based on a single fluorescent probe,allowing for rapid and robust profiling gut microbiota and their key metabolites including cysteine(Cys),glutathione(GSH),and homocysteine(Hcy).The assay leverages the single fluorescent probe that is with multiple binding sites and the cross-reactive sensing principle to specifically recognize different biological thiols.By analyzing the pattern of biological thiols,the assay is capable of rapidly identifying six gut-derived bacteria including probiotics,neutral,and pathogenic strains based on fluorescent fingerprints within 5 min,and also discriminating bacteria and their mixtures with different composition.Using the assay that enables the simultaneous measurement of multiple gut-derived bacteria and their metabolites,the designed array achieved an accuracy of 0.99 when discriminating colorectal cancer(CRC)patient feces samples from healthy individuals.Remarkably,the as-prepared sensor array can also be used to identify various stages of CRC.The simplicity,rapidness,and cost-effectiveness of our approach render it a robust platform for the analysis of gut microbiota.展开更多
Design and development of high-efficiency and durable oxygen evolution reaction(OER)electrocatalysts is crucial for hydrogen production from seawater splitting.Herein,we report the in situ electrochemical conversion o...Design and development of high-efficiency and durable oxygen evolution reaction(OER)electrocatalysts is crucial for hydrogen production from seawater splitting.Herein,we report the in situ electrochemical conversion of a nanoarray of Ni(TCNQ)2(TCNQ=tetracyanoquinodimethane)on graphite paper into Ni(OH)_(2) nanoparticles confined in a conductive TCNQ nanoarray(Ni(OH)_(2)-TCNQ/GP)by anode oxidation.The Ni(OH)_(2)-TCNQ/GP exhibits high OER performance and demands overpotentials of 340 and 382 mV to deliver 100 mA·cm^(−2) in alkaline freshwater and alkaline seawater,respectively.Meanwhile,the Ni(OH)_(2)-TCNQ/GP also demonstrates steady long-term electrochemical durability for at least 80 h under alkaline seawater.展开更多
Leaf angle(LA)is a crucial factor that affects planting density and yield in maize.However,the regulatory mechanisms underlying LA formation remain largely unknown.In this study,we performed a comparative histological...Leaf angle(LA)is a crucial factor that affects planting density and yield in maize.However,the regulatory mechanisms underlying LA formation remain largely unknown.In this study,we performed a comparative histological analysis of the ligular region across various maize inbred lines and revealed that LA is significantly influenced by a two-step regulatory process involving initial cell elongation followed by subsequent lignification in the ligular adaxial sclerenchyma cells(SCs).Subsequently,we performed both bulk and single-nucleus RNA sequencing,generated a comprehensive transcriptomic atlas of the ligular region,and identified numerous genes enriched in the hypodermal cells that may influence their specialization into SCs.Furthermore,we functionally characterized two genes encoding atypical basic-helix-loop-helix(bHLH)transcription factors,bHLH30 and its homolog bHLH155,which are highly expressed in the elongated adaxial cells.Genetic analyses revealed that bHLH30 and bHLH155 positively regulate LA expansion,and molecular experiments demonstrated their ability to activate the transcription of genes involved in cell elongation and lignification of SCs.These findings highlight the specialized functions of ligular adaxial SCs in LA regulation by restricting further extension of ligular cells and enhancing mechanical strength.The transcriptomic atlas of the ligular region at single-nucleus resolution not only deepens our understanding of LA regulation but also enables identification of numerous potential targets for optimizing plant architecture in modern maize breeding.展开更多
Application of differentiation therapy targeting cellular plasticity for the treatment of solid malignancies has been lagging.Nasopharyngeal carci noma(NPC)is a distinctive cancer with poor differe ntiatio n and high ...Application of differentiation therapy targeting cellular plasticity for the treatment of solid malignancies has been lagging.Nasopharyngeal carci noma(NPC)is a distinctive cancer with poor differe ntiatio n and high prevalenee of Epstein-Barr virus(EBV)infection.Here,we show that the expressi on of EBV latent protein LMP1 in duces dediffere ntiated and stem-like status with high plasticity through the transcriptional inhibition of CEBPA.Mechanistically,LMP1 upregulates STAT5A and recruits HDAC 1/2 to the CEBPA locus to reduce its histone acetylation.HDAC inhibition restored CEBPA expression,reversing cellular dedifferentiation and stem-like status in mouse xeno graft models.These fin dings provide a novel mecha nistic epigenetic-based in sight into virus-induced cellular plasticity and propose a promising concept of differentiation therapy in solid tumor by using HDAC inhibitors to target cellular plasticity.展开更多
Background:Overexpression of Aurora-A(AURKA)is a feature of breast cancer and associates with adverse prognosis.The selective Aurora-A inhibitor alisertib(MLN8237)has recently demonstrated promising antitumor response...Background:Overexpression of Aurora-A(AURKA)is a feature of breast cancer and associates with adverse prognosis.The selective Aurora-A inhibitor alisertib(MLN8237)has recently demonstrated promising antitumor responses as a single agent in various cancer types but its phase III clinical trial was reported as a failure since MLN8237 did not show an apparent effect in prolonging the survival of patients.Thus,identification of potential targets that could enhance the activity of MLN8237 would provide a rationale for drug combination to achieve better therapeutic outcome.Methods:Here,we conducted a systematic synthetic lethality CRISPR/Cas9 screening of 507 kinases using MLN8237 in breast cancer cells and identified a number of targetable kinases that displayed synthetic lethality interactions with MLN8237.Then,we performed competitive growth assays,colony formation assays,cell viability assays,apoptosis assays,and xenograft murine model to evaluate the synergistic therapeutic effects of Haspin(GSG2)depletion or inhibition with MLN8237.For mechanistic studies,immunofluorescence was used to detect the state of microtubules and the localization of Aurora-B and mitotic centromere-associated kinesin(MCAK).Results:Among the hits,we observed that Haspin depletion or inhibition marginally inhibited breast cancer cell growth but could substantially enhance the killing effects of MLN8237.Mechanistic studies showed that co-treatment with Aurora-A and Haspin inhibitors abolished the recruitment of Aurora-B and mitotic centromere-associated kinesin(MCAK)to centromeres which were associated with excessive microtubule depolymerization,kinetochore-microtubule(KT-MT)attachment failure,and severe mitotic catastrophe.We further showed that the combination of MLN8237 and the Haspin inhibitor CHR-6494 synergistically reduced breast cancer cell viability and significantly inhibited both in vitro and in vivo tumor growth.Conclusions:These findings establish Haspin as a synthetic lethal target and demonstrate CHR-6494 as a potential combinational drug for promoting the therapeutic effects of MLN8237 on breast cancer.展开更多
Electrochemical reduction of NO offers us an attractive alternative to traditional selective catalytic reduction process for harmful NO removal and simultaneous NH_(3)production,but it requires efficient electrocataly...Electrochemical reduction of NO offers us an attractive alternative to traditional selective catalytic reduction process for harmful NO removal and simultaneous NH_(3)production,but it requires efficient electrocatalyst to enable the NO reduction reaction with high selectivity.Here,we report on the development of Bi nanoparticles/carbon nanosheet composite(Bi@C)for highly effective NO reduction electrocatalysis toward selective NH_(3)formation.Such Bi@C catalyst attains an impressive NH_(3)yield of 1,592.5μg·h^(−1)·mgcat.^(−1)and a high Faradaic efficiency as high as 93%in 0.1 M Na_(2)SO_(4)electrolyte.Additionally,it can be applied as efficient cathode materials for Zn–NO battery to reduce NO to NH_(3)with high electricity generation.展开更多
Cu-based metal organic frameworks(MOFs)are regarded as promising sensing materials,which have abundant metal sites,large surface area and simple synthesis processes.In this work,a novel three-dimensional flower-like C...Cu-based metal organic frameworks(MOFs)are regarded as promising sensing materials,which have abundant metal sites,large surface area and simple synthesis processes.In this work,a novel three-dimensional flower-like Cu-MOF was synthesized,which was combined with ultra-thin MXene nanosheets to construct a novel electrochemical sensor for H_(2)O_(2).展开更多
The structures of the solar-thermal membranes always influence the performance of light absorption and salt resistance in desalination.Inspired by the hierarchical structure of the coniferous leaves with excellent sun...The structures of the solar-thermal membranes always influence the performance of light absorption and salt resistance in desalination.Inspired by the hierarchical structure of the coniferous leaves with excellent sunlight absorption in frigid regions,a coniferous leaf-like nickel black(L-Ni)membrane for desalination by solar-thermal energy conversion was prepared through electroplating method under a constant voltage.The light trapping effect of coniferous leaf-like structure led to the light absorption enhanced to 92%,the evaporation rate improved to 1.38 kg·m^(-2)·h^(-1),and the solar-vapor conversion efficiency of L-Ni membrane reaching up to 89.75%under 1 sun irradiation.The stability of the membrane was still excellent after 20 cycles desalination because the coniferous leaf-like structure could enhance the hydrophobicity(water contact angle:152°)of the L-Ni membrane,and it was beneficial to salt resistance.The promising performance of L-Ni membrane with coniferous leaf-like structure provides a possibility to replace the noble metal solar-thermal conversion materials.展开更多
Background:Late-onset depression(LOD)and early-onset depression(EOD)exhibit different pathological mechanisms and clinical phenotypes,including different extents of olfactory dysfunction.However,the brain abnormalitie...Background:Late-onset depression(LOD)and early-onset depression(EOD)exhibit different pathological mechanisms and clinical phenotypes,including different extents of olfactory dysfunction.However,the brain abnormalities underlying the differences in ol-factory dysfunction between EOD and LOD remain unclear.Objective:The aim of this study was to compare the functional connectivity(FC)patterns of olfactory regions between EOD patients and LOD patients and examine their relationship with cognitive function.Methods:One hundred and five patients with EOD,101 patients with LOD and 160 normal controls(NCs)were recruited for the present study.Participants underwent clinical assessment,olfactory testing,cognitive assessments,and magnetic resonance imaging.Eight regions of the primary and secondary olfactory regions were selected to investigate olfactory FC.Results:Patients with LOD exhibited decreased odor identification(OI)compared with patients with EOD and NCs.The LOD group exhibited decreased FC compared with the EOD and NC groups when primary and secondary olfactory regions were selected as the regions of interest(the piriform cortex,lateral entorhinal cortex,and orbital-frontal cortex).Additionally,these abnormal olfactory FCs were associated with decreased cognitive function scores and OI,and the FC between the left orbital-frontal cortex and left amygdala was a partial mediator of the relationship between global cognitive scores and OI.Conclusion:Overall,patients with LOD exhibited decreased FC in both the primary and secondary olfactory cortices compared with patients with EOD,and abnormal olfactory FC was associated with OI dysfunction and cognitive impairment.The FC between the orbital-frontal cortex and amygdala mediated the relationship between global cognitive function and OI.展开更多
Ubiquitous competition of stereospecific E2 elimination versus SN2 substitution is of central importance in chemical synthesis.Herein,we uncover how the nature of the leaving group affects the intrinsic competing dyna...Ubiquitous competition of stereospecific E2 elimination versus SN2 substitution is of central importance in chemical synthesis.Herein,we uncover how the nature of the leaving group affects the intrinsic competing dynamics that remains largely unknown as opposed to its role in reactivity.Results are presented for a prototype case of fluoride anion reacting with ethyl chloride,compared to reacting with ethyl iodide.Chemical dynamics simulations reproduce scattering signatures observed in experiments and reveal that the direct stripping/rebound mechanisms characterize the E2/S_(N)2 reactions,in line with their dynamic fingerprints identified.Quite similar structures and energetics are found for the Cl^(−)and I^(−)leaving halides,whereas the competing dynamics show markedly distinct features.A halogen-bonding attraction is found to be crucial that modifies the interaction potential in the entrance channel and essentially tunes the underlying atomistic behaviors causing a mechanistic shift.This work highlights the dynamical effects induced by a leaving group on the proceedings of baseinduced elimination and nucleophilic substitution,providing a unique insight into the reaction selectivity for complex chemical networks and environments.展开更多
文摘Design and control of pressure-swing distillation(PSD) with different heat integration modes for the separation of methyl acetate/methanol azeotrope are explored using Aspen Plus and Aspen Dynamics. First, an optimum steady-state separation configuration conditions are obtained via taking the total annual cost(TAC) or total reboiler heat duty as the objective functions. The results show that about 27.68% and 25.40% saving in TAC can be achieved by the PSD with full and partial heat integration compared to PSD without heat integration. Second,temperature control tray locations are obtained according to the sensitivity criterion and singular value decomposition(SVD) analysis and the single-end control structure is effective based on the feed composition sensitivity analysis. Finally, the comparison of dynamic controllability is made among various control structures for PSD with partial and full heat integration. It is shown that both control structures of composition/temperature cascade and pressure-compensated temperature have a good dynamic response performance for PSD with heat integration facing feed flowrate and composition disturbances. However, PSD with full heat integration performs the poor controllability despite of a little bit of economy.
基金supported by National Natural Science Foundation of China(Nos.22376057,22174048,22274048,22274045,22274047,and 21904039)the Foundation of the Science&Technology Department of Hunan Province(Nos.2023JJ30394 and2023ZJ1123)。
文摘Rapid and robust identification of bacteria is crucial for environmental monitoring and clinical diagnosis.Herein,a bioinspired interface-mediated multichannel sensor array was developed based on three-coloremitting antimicrobial functional carbon dots(FCDs)and concanavalin A doped polydopamine nanoparticles(Con A-PDA)for identification of bacteria.In this sensor,the fluorescence intensity of the three FCDs was quenched by the Con A-PDA.Upon addition different types of bacteria,the fluorescence intensity of the three FCDs was restored or further quenched.Recur to statistical analysis methods,it is employed to accurately discriminate 10 types of bacteria(including three probiotics and seven pathogenic bacteria)in natural water samples and human urine samples.The discrimination ability of the sensor array was highly enhanced via different competing binding of the FCDs and the bacteria toward Con A-PDA.The proposed array-based method offers a rapid,high-throughput,and reliable sensing platform for pathogen diagnosis in the field of environmental monitoring and clinical diagnosis.
基金supported by the National Natural Science Foundation of China(Grant No.91125029)the State Key Development Program for Basic Research of China(973 Program,Grant No.2013CB429904)
文摘In order to obtain qualitative and quantitative characteristics of leaf epidermal micromorphology and mesophyll structure to evaluate the responses ofElaeagnus angustifolia L. to different environmental factors, epidermal micromorphology was observed by scanning electron microscopy （SEM）, and mesophyll structure was studied by light microscopy （LM） and transmission electron microscopy （TEM）. Materials were selected from Linze County, Gansu Province （material A） and Qitai County, Xinjiang Uygur Autonomous Region （material B） of China. Results show that lamina thickness was higher in material A, with one layer of epidermal cells in both adaxial and abaxial surfaces, and epidermal cell radial length was significantly longer in the adaxial surface. E. angustifolia leaves are typically bifacial, with a higher ratio of palisade to spongy tissue in material A. The thickness of trichome layer of epidermis was thicker in material A. In contrast, cell wall and cuticular wax of the epidermal cells were thinner in material A than in material B. Chloroplast ultrastructure was different with the approximate spherical chloroplast containing numerous starch grains and osmiophilic granules in ma- terial A, while only the spindly chloroplast contained starch grains in material B. Multiple layers of peltate or stel- late-peltate trichomes occupied both leaf surfaces in material A and the abaxial surface in material B, while the adaxial surface of material B contained few trichomes. Stomata were not observed on the leaf surfaces in materials A and B by SEM because of trichome obstruction. Our results indicate that the leaf structure of E. angustifolia is closely correlated with environmental factors, and the combination of leaf epidermal micromorphology and mesophyll structure afford re- sistance to environmental stress.
基金supported by the National Natural Science Foundation of China(31600332,31700373)the CAS"Light of West China"Program,and funds of Gansu Academy of Science(2019CX004-01,CY04,2018JK-04).
文摘Plant density and spatial distribution in artificial vegetation is obviously initialized at the planting stage. Plant dynamics and spatial pattern may change over time as the result of interactions between individual plants and habitats, but whether it’s applied for desert shrubs in artificial sand-fixing regions remains unknown. Here we examined changes in plant density and distribution patterns of three shrubs(Artemisia ordosica Krasch, Caragana korshinskii Kom, and Hedysarum scoparium Fisch.) in different regions, which have been restored for 27, 32 and 50 years(R27, R32, R50), respectively. The vegetation analysis shows that A. ordosica was the dominated species across the 3 restoration regions. The density of A. ordosica and H. scoparium show a significant increase from R27 to R32, then decreased in R50. The density of C. korshinskii was low in R32 and R50, lower in R27. The variance-to-mean ratio(VMR) was used to characterize spatial distribution patterns to fit the observed densities of the three shrubs by frequency. A. ordosica and C. korshinskii both show significantly clumped distributions in three restoration regions. H. scoparium show a uniform distribution in R27 and R50, but a clumped distribution in R32. These results show that A. ordosica seems to be more adaptable in revegetated desert areas compared to C. korshinskii and H. scoparium. Pattern analysis suggests a successive replacement of C. korshinskii, which had low proportions of survived shrubs, by the dominant A. ordosica. This study contributes to the understanding of the distribution patterns of shrubs plants in revegetation projects in arid desert areas.
基金financially supported by the National Natural Science Foundation of China(31070358,91125029,31160089 and 31000181)
文摘Reaumuria soongorica is a short woody shrub widely found in semi-arid areas of China. It can survive severe environ- mental stress including high salinity in its natural habitat. Thus, we investigated the involvement of anti-oxidative enzymes, photosynthetic pigments and flavonoid metabolism in the adaptation of R. soongorica to saline environments. R. soon- gorica was treated with 0, 100, 200 and 400 mM NaC1 solutions for 14 days. Soil salt content increased significantly by watering with high content of NaC1 solution, and no variation between 8 and 14 days during treatment. The levels ofpe- roxidation of lipid membranes （measured by malondialdehyde content） and the activities of three antioxidant enzymes （superoxide dismutase （SOD）, peroxidase （POD） and ascorbate peroxidase （APX）） increased under salt stress. Chlorophyll and carotenoid content decreased with increasing salt content. The ratio of Chl a/Chl b and carotenoid/Chl exhibited sig- nificant increase under 400 mM NaC1. However, total flavonoid and anthocyanin contents and key enzyme activities in the flavonoid pathway including phenylalanine ammonialyase （PAL） and Chalcone isomerase （CHI） decreased under salt stress. These findings possibly suggest that R. soongorica has an adaptation protection mechanism against salt-induced oxidative damage by inducin~ the activity of antioxidant enzymes and maintaining a steady level of carotenoid/Chl.
基金supported by the National Natural Science Foundation of China(22274048,22274045,22376057,22274047,21904039,22474038,82273466)the Foundation of the Science&Technology Department of Hunan Province(2023JJ30394,2024JJ2039,2023ZJ1123)。
文摘Rapid and accurate diagnosis of oral cancer aggressiveness is associated with preoperative guidance and postoperative treatment.However,traditional diagnostic methods are time-consuming and easily misdiagnosed,which makes it challenging to achieve high-precision classification.Herein,we introduce a recognition engineering-mediated multichannel nanosensor for the analysis of tumor metabolites,allowing for sensitive and rapid in vitro and intraoperative cancer malignancy discrimination.This nanosensor system utilizes engineered carbon dots(CDs)with various ratios of amino and carboxyl functional groups,assembled as a“shell”on gold nanoparticles(AuNPs).The multichannel nanosensor displayed distinct fingerprint patterns for fourteen tumor metabolites such as amino acids,nucleic acids,and other metabolites.It offers rapid“turn-on”fluorescence-encoded profiling,generating unique signatures for cancer malignancy within 15 min.The nanosensor demonstrated 100%accuracy in identifying the oral squamous cell carcinoma(OSCC)subtype and assessing malignancy levels.It will provide detailed pathology for the identification of clinical cancer tissue samples,including cancer cell subtype and differentiation grade.Together,our study highlights the potential of the fluorescent-encoded multichannel nanosensor as a powerful in vitro and intraoperative diagnostic tool for cancer malignancy and treatment guidance in advanced clinical oncology.
基金supported by the National Natural Science Foundation of China(22274047,21974042,22274048)the Scientific Research Fund of Hunan Provincial Education Department(18A010)+2 种基金the Science and Technology Department of Hunan Province(2021JJ30012)the Hubei Science and Technology Program(2022CFB781)the Innovation Team of Hubei University of Science and Technology(2023T13)。
文摘Single-atom nanozymes(SANzymes)with multi-mimetic activities capable of altering the cellular redox balance demonstrate significant potential in tumor therapy.However,the catalytic treatment provided by SANzymes alone is insufficient to achieve optimal outcomes.Therefore,the combination of nanozyme catalysis with drug therapy is considered a promising alternative.Nonetheless,the leakage of drug molecules is a primary cause of chemotherapy resistance in cancer treatment.Consequently,developing novel drug immobilization methods to attach them to SANzymes is expected to enable multimodal synergistic therapy.Herein,a multifunctional nanoplatform is designed by modifying bioinspired PDA on iron-based SANzyme(Fe SANzyme)and immobilizing doxorubicin(DOX)through Michael addition/Schiff base reaction,which greatly promotes the drug loading efficiency.The Fe SAN-PDA@DOX@HA displays controllable drugs release behavior in the tumor microenvironment(TME),where the Fe SAN-PDA nanozyme can catalyze high level of H_(2)O_(2)to produce oxygen to alleviate hypoxia,convert H_(2)O_(2)to the toxic reactive oxygen species(ROS),and deplete intracellular glutathione via the catalase(CAT),peroxidase(POD),and glutathione oxidase(GSHOx)-like activities,respectively.The high drug loading,exceptional nanozyme catalysis,combined with the good photothermal performance of Fe SAN-PDA,resulted in sustained chemodynamic/photothermal/chemotherapy in a mouse mammary carcinoma model.The results reveal the synergistic antitumor potential of the novel conjugation of DOX on Fe SANzyme via PDA,offering a strategy for drug immobilization,TME remodeling and synergistic multimodal therapy.
基金supported by the National Natural Science Foundation of China(22376057,22274048,22274045,22074100,22274047,22104033)the Foundation of the Science&Technology Department of Hunan Province(2021ZJ1123,2023JJ30394)support from China Postdoctoral Science Foundation(2023M731053)。
文摘The gut microbiota and the associated metabolism play a pivotal role in maintaining human health,yet their assessment is challenging due to their inherent diversity,variety,and complexity.Herein,we developed a multichannel sensor array based on a single fluorescent probe,allowing for rapid and robust profiling gut microbiota and their key metabolites including cysteine(Cys),glutathione(GSH),and homocysteine(Hcy).The assay leverages the single fluorescent probe that is with multiple binding sites and the cross-reactive sensing principle to specifically recognize different biological thiols.By analyzing the pattern of biological thiols,the assay is capable of rapidly identifying six gut-derived bacteria including probiotics,neutral,and pathogenic strains based on fluorescent fingerprints within 5 min,and also discriminating bacteria and their mixtures with different composition.Using the assay that enables the simultaneous measurement of multiple gut-derived bacteria and their metabolites,the designed array achieved an accuracy of 0.99 when discriminating colorectal cancer(CRC)patient feces samples from healthy individuals.Remarkably,the as-prepared sensor array can also be used to identify various stages of CRC.The simplicity,rapidness,and cost-effectiveness of our approach render it a robust platform for the analysis of gut microbiota.
基金supported by the National Natural Science Foundation of China(No.22072015)the Opening Fund of Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research(Hunan Normal University)Ministry of Education(2020-02).
文摘Design and development of high-efficiency and durable oxygen evolution reaction(OER)electrocatalysts is crucial for hydrogen production from seawater splitting.Herein,we report the in situ electrochemical conversion of a nanoarray of Ni(TCNQ)2(TCNQ=tetracyanoquinodimethane)on graphite paper into Ni(OH)_(2) nanoparticles confined in a conductive TCNQ nanoarray(Ni(OH)_(2)-TCNQ/GP)by anode oxidation.The Ni(OH)_(2)-TCNQ/GP exhibits high OER performance and demands overpotentials of 340 and 382 mV to deliver 100 mA·cm^(−2) in alkaline freshwater and alkaline seawater,respectively.Meanwhile,the Ni(OH)_(2)-TCNQ/GP also demonstrates steady long-term electrochemical durability for at least 80 h under alkaline seawater.
基金supported by the National Natural Science Foundation of China(32270263)the Key R&D Program of Shandong Province(ZR202211070163)the Taishan Scholars program(to B.L.),and the China Postdoctoral Science Foundation(2023M742154).
文摘Leaf angle(LA)is a crucial factor that affects planting density and yield in maize.However,the regulatory mechanisms underlying LA formation remain largely unknown.In this study,we performed a comparative histological analysis of the ligular region across various maize inbred lines and revealed that LA is significantly influenced by a two-step regulatory process involving initial cell elongation followed by subsequent lignification in the ligular adaxial sclerenchyma cells(SCs).Subsequently,we performed both bulk and single-nucleus RNA sequencing,generated a comprehensive transcriptomic atlas of the ligular region,and identified numerous genes enriched in the hypodermal cells that may influence their specialization into SCs.Furthermore,we functionally characterized two genes encoding atypical basic-helix-loop-helix(bHLH)transcription factors,bHLH30 and its homolog bHLH155,which are highly expressed in the elongated adaxial cells.Genetic analyses revealed that bHLH30 and bHLH155 positively regulate LA expansion,and molecular experiments demonstrated their ability to activate the transcription of genes involved in cell elongation and lignification of SCs.These findings highlight the specialized functions of ligular adaxial SCs in LA regulation by restricting further extension of ligular cells and enhancing mechanical strength.The transcriptomic atlas of the ligular region at single-nucleus resolution not only deepens our understanding of LA regulation but also enables identification of numerous potential targets for optimizing plant architecture in modern maize breeding.
基金supported by National Key R&D Program of China(2019YFA0110300,2017YFA0505600-04 to Q.L.)Innovative Research Team in University of Ministry of Education of China(IRT_17R15 to Q.L.)+7 种基金National Natural Science Foundation of China(81630005,81573025 to Q.L.,81773166 to Z.W.,81702683 to J.X.,81972594 to M.Y.,81402445 to C.W.,81502579 to Z.H.)Natural Science Foundation of Guangdong(2017A030313608 to Q.L,2018A0303130299,2020A1515010608 to M.Y.)the Science and Technology Planning Project of Guangzhou(201804020044 to Q.L.)the Key Project of Liaoning Natural Science Funding of China(201702031 to Q.L.)Fundamental Research Funds for the Central Universities(I9ykpy187 to M.Y.).EW-FL's work is supported by MRC(MR/N012097/1)CRUK(Al 2011)Breast Cancer Now(2012MayPR070,2012NovPhD016)the Cancer Research UK Imperial Centre,Imperial ECMC,and NIHR Imperial BRC.
文摘Application of differentiation therapy targeting cellular plasticity for the treatment of solid malignancies has been lagging.Nasopharyngeal carci noma(NPC)is a distinctive cancer with poor differe ntiatio n and high prevalenee of Epstein-Barr virus(EBV)infection.Here,we show that the expressi on of EBV latent protein LMP1 in duces dediffere ntiated and stem-like status with high plasticity through the transcriptional inhibition of CEBPA.Mechanistically,LMP1 upregulates STAT5A and recruits HDAC 1/2 to the CEBPA locus to reduce its histone acetylation.HDAC inhibition restored CEBPA expression,reversing cellular dedifferentiation and stem-like status in mouse xeno graft models.These fin dings provide a novel mecha nistic epigenetic-based in sight into virus-induced cellular plasticity and propose a promising concept of differentiation therapy in solid tumor by using HDAC inhibitors to target cellular plasticity.
基金This research work was supported by the National Key R&D Program of China(2019YFA0110300 and 2017YFA0505600-04 to QL)the National Natural Science Foundation of China(81820108024 and 81630005 to QL,81773166 to ZFW)+2 种基金the Innovative Research Team at the University of Ministry of Education of China(IRT-17R15 to QL)the Natural Science Foundation of Guangdong(2016A030311038 and 2017A030313608 to QL,2017A020215098 to ZFW)the Science and Technology Planning Project of Guangzhou(201804020044 to QL).
文摘Background:Overexpression of Aurora-A(AURKA)is a feature of breast cancer and associates with adverse prognosis.The selective Aurora-A inhibitor alisertib(MLN8237)has recently demonstrated promising antitumor responses as a single agent in various cancer types but its phase III clinical trial was reported as a failure since MLN8237 did not show an apparent effect in prolonging the survival of patients.Thus,identification of potential targets that could enhance the activity of MLN8237 would provide a rationale for drug combination to achieve better therapeutic outcome.Methods:Here,we conducted a systematic synthetic lethality CRISPR/Cas9 screening of 507 kinases using MLN8237 in breast cancer cells and identified a number of targetable kinases that displayed synthetic lethality interactions with MLN8237.Then,we performed competitive growth assays,colony formation assays,cell viability assays,apoptosis assays,and xenograft murine model to evaluate the synergistic therapeutic effects of Haspin(GSG2)depletion or inhibition with MLN8237.For mechanistic studies,immunofluorescence was used to detect the state of microtubules and the localization of Aurora-B and mitotic centromere-associated kinesin(MCAK).Results:Among the hits,we observed that Haspin depletion or inhibition marginally inhibited breast cancer cell growth but could substantially enhance the killing effects of MLN8237.Mechanistic studies showed that co-treatment with Aurora-A and Haspin inhibitors abolished the recruitment of Aurora-B and mitotic centromere-associated kinesin(MCAK)to centromeres which were associated with excessive microtubule depolymerization,kinetochore-microtubule(KT-MT)attachment failure,and severe mitotic catastrophe.We further showed that the combination of MLN8237 and the Haspin inhibitor CHR-6494 synergistically reduced breast cancer cell viability and significantly inhibited both in vitro and in vivo tumor growth.Conclusions:These findings establish Haspin as a synthetic lethal target and demonstrate CHR-6494 as a potential combinational drug for promoting the therapeutic effects of MLN8237 on breast cancer.
基金supported by the National Natural Science Foundation of China(No.22072015)the Opening Fund of Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research(Hunan Normal University),Ministry of Education(2020-02).
文摘Electrochemical reduction of NO offers us an attractive alternative to traditional selective catalytic reduction process for harmful NO removal and simultaneous NH_(3)production,but it requires efficient electrocatalyst to enable the NO reduction reaction with high selectivity.Here,we report on the development of Bi nanoparticles/carbon nanosheet composite(Bi@C)for highly effective NO reduction electrocatalysis toward selective NH_(3)formation.Such Bi@C catalyst attains an impressive NH_(3)yield of 1,592.5μg·h^(−1)·mgcat.^(−1)and a high Faradaic efficiency as high as 93%in 0.1 M Na_(2)SO_(4)electrolyte.Additionally,it can be applied as efficient cathode materials for Zn–NO battery to reduce NO to NH_(3)with high electricity generation.
基金financially supported by the National Key Research and Development Program of China(No.2016YFA0203101)the National Natural Science Foundation of China(Nos.21974042,21904039,21874080,21645008,21621003,21622506)+1 种基金the Sci-entific Research Fund of Hunan Provincial Education Department(No.18A010)the Science and Technology Department of Hunan Province(Nos.14JJ4030,2020JJ5352).
文摘Cu-based metal organic frameworks(MOFs)are regarded as promising sensing materials,which have abundant metal sites,large surface area and simple synthesis processes.In this work,a novel three-dimensional flower-like Cu-MOF was synthesized,which was combined with ultra-thin MXene nanosheets to construct a novel electrochemical sensor for H_(2)O_(2).
基金The authors gratefully acknowledge the National Key R&D Program of China(Nos.2022YFB3903200 and 2022YFB3903203)the Natural Science Foundation of Jilin Province(No.20210101392JC).
文摘The structures of the solar-thermal membranes always influence the performance of light absorption and salt resistance in desalination.Inspired by the hierarchical structure of the coniferous leaves with excellent sunlight absorption in frigid regions,a coniferous leaf-like nickel black(L-Ni)membrane for desalination by solar-thermal energy conversion was prepared through electroplating method under a constant voltage.The light trapping effect of coniferous leaf-like structure led to the light absorption enhanced to 92%,the evaporation rate improved to 1.38 kg·m^(-2)·h^(-1),and the solar-vapor conversion efficiency of L-Ni membrane reaching up to 89.75%under 1 sun irradiation.The stability of the membrane was still excellent after 20 cycles desalination because the coniferous leaf-like structure could enhance the hydrophobicity(water contact angle:152°)of the L-Ni membrane,and it was beneficial to salt resistance.The promising performance of L-Ni membrane with coniferous leaf-like structure provides a possibility to replace the noble metal solar-thermal conversion materials.
基金supported by a grant from the National Natu-ral Science Foundation of China (nos 82171533,82101508)Medical Scientific Technology Research Foundation of Guangdong Province of China (no.A2020446)the Key Laboratory for Innovation Platform Plan,the Science and Technology Program of Guangzhou,China,the Science and Technology Plan Project of Guangdong Province (no.2019B030316001).
文摘Background:Late-onset depression(LOD)and early-onset depression(EOD)exhibit different pathological mechanisms and clinical phenotypes,including different extents of olfactory dysfunction.However,the brain abnormalities underlying the differences in ol-factory dysfunction between EOD and LOD remain unclear.Objective:The aim of this study was to compare the functional connectivity(FC)patterns of olfactory regions between EOD patients and LOD patients and examine their relationship with cognitive function.Methods:One hundred and five patients with EOD,101 patients with LOD and 160 normal controls(NCs)were recruited for the present study.Participants underwent clinical assessment,olfactory testing,cognitive assessments,and magnetic resonance imaging.Eight regions of the primary and secondary olfactory regions were selected to investigate olfactory FC.Results:Patients with LOD exhibited decreased odor identification(OI)compared with patients with EOD and NCs.The LOD group exhibited decreased FC compared with the EOD and NC groups when primary and secondary olfactory regions were selected as the regions of interest(the piriform cortex,lateral entorhinal cortex,and orbital-frontal cortex).Additionally,these abnormal olfactory FCs were associated with decreased cognitive function scores and OI,and the FC between the left orbital-frontal cortex and left amygdala was a partial mediator of the relationship between global cognitive scores and OI.Conclusion:Overall,patients with LOD exhibited decreased FC in both the primary and secondary olfactory cortices compared with patients with EOD,and abnormal olfactory FC was associated with OI dysfunction and cognitive impairment.The FC between the orbital-frontal cortex and amygdala mediated the relationship between global cognitive function and OI.
基金supported by the State Key Lab of Urban Water Resource and Environment of the Harbin Institute of Technology(No.ES202303)。
文摘Ubiquitous competition of stereospecific E2 elimination versus SN2 substitution is of central importance in chemical synthesis.Herein,we uncover how the nature of the leaving group affects the intrinsic competing dynamics that remains largely unknown as opposed to its role in reactivity.Results are presented for a prototype case of fluoride anion reacting with ethyl chloride,compared to reacting with ethyl iodide.Chemical dynamics simulations reproduce scattering signatures observed in experiments and reveal that the direct stripping/rebound mechanisms characterize the E2/S_(N)2 reactions,in line with their dynamic fingerprints identified.Quite similar structures and energetics are found for the Cl^(−)and I^(−)leaving halides,whereas the competing dynamics show markedly distinct features.A halogen-bonding attraction is found to be crucial that modifies the interaction potential in the entrance channel and essentially tunes the underlying atomistic behaviors causing a mechanistic shift.This work highlights the dynamical effects induced by a leaving group on the proceedings of baseinduced elimination and nucleophilic substitution,providing a unique insight into the reaction selectivity for complex chemical networks and environments.
