Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic netw...Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic network on FAA biosynthesis remains unclear.Through metagenomic analysis,this work aimed to elucidate the roles of microbes in FAA biosynthesis during Monascus rice vinegar fermentation.Taxonomic profiles from functional analyses showed 14 dominant genera with high contributions to the metabolism pathways.The metabolic network for FAA biosynthesis was then constructed,and the microbial distribution in different metabolic pathways was illuminated.The results revealed that 5 functional genera were closely involved in FAA biosynthesis.This study illuminated the metabolic roles of microorganisms in FAA biosynthesis and provided crucial insights into the functional attributes of microbiota in vinegar fermentation.展开更多
Modern medicine is increasingly interested in advanced sensors to detect and analyze biochemical indicators.Ion sensors based on potentiometric methods are a promising platform for monitoring physiological ions in bio...Modern medicine is increasingly interested in advanced sensors to detect and analyze biochemical indicators.Ion sensors based on potentiometric methods are a promising platform for monitoring physiological ions in biological subjects.Current semi-implantable devices are mainly based on single-parameter detection.Miniaturized semi-implantable electrodes for multiparameter sensing have more restrictions on the electrode size due to biocompatibility considerations,but reducing the electrode surface area could potentially limit electrode sensitivity.This study developed a semi-implantable device system comprising a multiplexed microfilament electrode cluster(MMEC)and a printed circuit board for real-time monitoring of intra-tissue K^(+),Ca^(2+),and Na^(+)concentrations.The electrode surface area was less important for the potentiometric sensing mechanism,suggesting the feasibility of using a tiny fiber-like electrode for potentiometric sensing.The MMEC device exhibited a broad linear response(K^(+):2–32 mmol/L;Ca^(2+):0.5–4 mmol/L;Na^(+):10–160 mmol/L),high sensitivity(about 20–45 mV/decade),temporal stability(>2weeks),and good selectivity(>80%)for the above ions.In vitro detection and in vivo subcutaneous and brain experiment results showed that the MMEC system exhibits good multi-ion monitoring performance in several complex environments.This work provides a platform for the continuous real-time monitoring of ion fluctuations in different situations and has implications for developing smart sensors to monitor human health.展开更多
The integral impeller and blisk of an aero-engine are high performance parts with complex structure and made of difficult-to-cut materials. The blade surfaces of the integral impeller and blisk are functional surfaces...The integral impeller and blisk of an aero-engine are high performance parts with complex structure and made of difficult-to-cut materials. The blade surfaces of the integral impeller and blisk are functional surfaces for power transmission, and their surface integrity has signif- icant effects on the aerodynamic efficiency and service life of an aero-engine. Thus, it is indispensable to finish and strengthen the blades before use. This paper presents a comprehensive literature review of studies on finishing and strengthening technologies for the impeller and blisk of aero-engines. The review includes independent and inte- grated finishing and strengthening technologies and dis- cusses advanced rotational abrasive flow machining with back-pressure used for finishing the integral impeller and blisk. A brief assessment of future research problems and directions is also presented.展开更多
The surface plasmonic resonance(SPR)effect of Bi can effectively improve the light absorption abilities and photogenerated charge carrier separation rate.In this study,a novel ternary heterojunction of g-C3N4/Bi2MoO6/...The surface plasmonic resonance(SPR)effect of Bi can effectively improve the light absorption abilities and photogenerated charge carrier separation rate.In this study,a novel ternary heterojunction of g-C3N4/Bi2MoO6/Bi(CN/BMO/Bi)hollow microsphere was successfully fabricated through solvothermal and in situ reduction methods.The results revealed that the optimal ternary 0.4 CN/BMO/9 Bi photocatalyst exhibited the highest photocatalytic efficiency toward rhodamine B(RhB)degradation with nine times that of pure BMO.The DRS and valence band of the X-ray photoelectron spectroscopy spectrum demonstrate that the band structure of 0.4 CN/BMO/9 Bi is a z-scheme structure.Quenching experiments also provided solid evidence that the·O^2-(at-0.33 eV)is the main species during dye degradation,and the conduction band of g-C3N4 is only the reaction site,demonstrating that the transfer of photogenerated charge carriers of g-C3N4/Bi2 MoO 6/Bi is through an indirect z-scheme structure.Thus,the enhanced photocatalytic performance was mainly ascribed to the synergetic effect of heterojunction structures between g-C3N4 and Bi2MoO6 and the SPR effect of Bi doping,resulting in better optical absorption ability and a lower combination rate of photogenerated charge carriers.The findings in this work provide insight into the synergism of heterostructures and the SPR absorption ability in wastewater treatment.展开更多
Tiered Mobile Wireless Sensor Network(TMWSN)is a new paradigm introduced by mobile edge computing.Now it has received wide attention because of its high scalability,robustness,deployment flexibility,and it has a wide ...Tiered Mobile Wireless Sensor Network(TMWSN)is a new paradigm introduced by mobile edge computing.Now it has received wide attention because of its high scalability,robustness,deployment flexibility,and it has a wide range of application scenarios.In TMWSNs,the storage nodes are the key nodes of the network and are more easily captured and utilized by attackers.Once the storage nodes are captured by the attackers,the data stored on them will be exposed.Moreover,the query process and results will not be trusted any more.This paper mainly studies the secure KNN query technology in TMWSNs,and we propose a secure KNN query algorithm named the Basic Algorithm For Secure KNN Query(BAFSKQ)first,which can protect privacy and verify the integrity of query results.However,this algorithm has a large communication overhead in most cases.In order to solve this problem,we propose an improved algorithm named the Secure KNN Query Algorithm Based on MR-Tree(SEKQAM).The MR-Trees are used to find the K-nearest locations and help to generate a verification set to process the verification of query results.It can be proved that our algorithms can effectively guarantee the privacy of the data stored on the storage nodes and the integrity of the query results.Our experimental results also show that after introducing the MR-Trees in KNN queries on TMWSNs,the communication overhead has an effective reduction compared to BAFSKQ.展开更多
The human immunodeficiency virus （HIV） lentiviral vector is an ideal vector for gene therapy. In the present study, the wild-type HIV-1 genome was segregated into four plasmids, and an optimized novel HIV-1 lentivir...The human immunodeficiency virus （HIV） lentiviral vector is an ideal vector for gene therapy. In the present study, the wild-type HIV-1 genome was segregated into four plasmids, and an optimized novel HIV-1 lentiviral vector containing green fluorescent protein and vesicular stomatitis virus G pseudo-capsule was constructed. The plasmids were pHR-CMV-EGFP, pCMVΔ8.9, pRSV-Rev, pCMV-VSV-G. The four plasmid system was co-transfected into 293T cells, and green fluorescent protein expression was observed. The present study obtained lentiviral particles by high-speed centrifugation, and the lentiviral particle titer was 4 × 108 TU/mL after centrifugation. Thus, an optimized novel HIV-1 lentiviral vector was successfully constructed.展开更多
Objective To investigate the etiology and relative factors of dilated cardiomyopathy （DCM） in Chinese patients. Methods A case-control study was conducted to compare 233 patients with DCM in high-incidence areas （c...Objective To investigate the etiology and relative factors of dilated cardiomyopathy （DCM） in Chinese patients. Methods A case-control study was conducted to compare 233 patients with DCM in high-incidence areas （case group） and 150 patients with stable angina pectoris （control group）. Life styles and history of diseases information was collected by questionaire; human anti-myocardial antibody lgG （AMA- IgG）, human Coxsackie B virus IgG （CBV- IgG） and human adenovirus antibody IgG （ADV- IgG） were measured with ELISA. General chemical and toxicological indicators in drink water from high and low prevalence areas and serum trace elements also were compared. Results 1） Compared with the control group, the case group had more farmers （P 〈 0.01）, with low average incomes （P 〈 0.01 ）, higher alcohol consumption （P 〈 0.01） and higher incidence of the history of myocarditis （P 〈 0.01）. 2） AMA-IgG, CBV-IgG and ADV-IgG levels were low and the positive rates ofAMA-IgG, CBV-IgG and ADV-IgG of patients with DCM were respectively 7.78%, 6.67% and 6.67%, no statistical significance comparing with those in the control group. 3） The content of iron （1.36±2.18 vs 0.39±0.67 rag/L, P〈0.05） and manganese （0.38±0.35 vs 0.15±0.14, P〈0.01） in drinking water of high-incidence areas was significantly higher than that in low-incidence areas. 4） The content of serum iron （69.1±57.8 vs 20.0±17.5 umol/L, P〈0.01 ） and copper （25.7±4.2 vs 19.7±4.5 umol/L, P〈0.01） in the case group evidently exceeded the normal range and obviously higher than that in the control group. Conclusions 1） The incidence of some DCM is related with low incomes, high alcohol consumption and myoearditis. 2） These data do not support that DCM is related with persistent virus infection and autoimmunization; 3） Iron and manganese contents exceeding standards in drinking water and the high content of serum iron and copper is comparatively related with the incidence of DCM.展开更多
Large-sized potassium dihydrogen phosphate(KDP)crystals are an irreplaceable nonlinear optical component in an inertial confinement fusion project.Restricted by the size,previous studies have been aimed mainly at the ...Large-sized potassium dihydrogen phosphate(KDP)crystals are an irreplaceable nonlinear optical component in an inertial confinement fusion project.Restricted by the size,previous studies have been aimed mainly at the removal principle and surface roughness of small-sized KDP crystals,with less research on flatness.Due to its low surface damage and high machining efficiency,water dissolution ultraprecision continuous polishing(WDUCP)has become a good technique for processing large-sized KDP crystals.In this technique,the trajectory uniformity of water droplets can directly affect the surface quality,such as flatness and roughness.Specifically,uneven trajectory distribution of water droplets on the surface of KDP crystals derived from the mode of motion obviously affects the surface quality.In this study,the material removal mechanism of WDUCP was introduced.A simulation of the trajectory of water droplets on KDP crystals under different eccentricity modes of motion was then performed.Meanwhile,the coefficient of variation(CV)was utilized to evaluate the trajectory uniformity.Furthermore,to verify the reliability of the simulation,some experimental tests were also conducted by employing a large continuous polisher.The results showed that the CV varied from 0.67 to 2.02 under the certain eccentricity mode of motion and varied from 0.48 to 0.65 under the uncertain eccentricity mode of motion.The CV of uncertain eccentricity is always smaller than that of certain eccentricity.Hence,the uniformity of trajectory was better under uncertain eccentricity.Under the mode of motion of uncertain eccentricity,the initial surface texture of the100 mm×100 mm×10 mm KDP crystal did achieve uniform planarization.The surface root mean square roughness was reduced to 2.182 nm,and the flatness was reduced to 22.013μm.Therefore,the feasibility and validity of WDUCP for large-sized KDP crystal were verified.展开更多
The hot pressing process parameters were optimized to prepare flax fiber reinforced polyethylene(PE)thermoplastic composite by the Taguchi method.The optimal hot pressing process parameters were determined to increase...The hot pressing process parameters were optimized to prepare flax fiber reinforced polyethylene(PE)thermoplastic composite by the Taguchi method.The optimal hot pressing process parameters were determined to increase the tensile strength of the composite.The optimal parameters of the design include the following sections:hot pressing temperature,pressure,hot pressing time and coupling agent modification time.An L9(3*4)orthogonal matrix based on the Taguchi method was created.By means of analysis of signal-to-noise ratio and analysis of variance,the optimal hot pressing process parameters combination was found,compared to the average tensile strength in the nine design experiments,and the tensile strength was improved nearly 10%.展开更多
Full utilization of the excited species at both singlet states(1R*)and triplet states(3R*)is crucial to improving electrochemiluminescence(ECL)efficiency but is challenging for organic luminescent materials.Here,an ag...Full utilization of the excited species at both singlet states(1R*)and triplet states(3R*)is crucial to improving electrochemiluminescence(ECL)efficiency but is challenging for organic luminescent materials.Here,an aggregation-induced delayed ECL(AIDECL)active organic dot(OD)containing a benzophenone acceptor and dimethylacridine donor is reported,which shows high ECL efficiency via reverse intersystem crossing(RISC)of non-emissive 3R*to emissive 1R*,overcoming the spin-forbidden radiative decay from 3R*.By introducing dual donor-acceptor pairs into luminophores,it is found that nonradiative pathway could be further suppressed via enhanced intermolecular weak interactions,and multiple spin-up conversion channels could be activated.As a consequence,the obtained OD enjoys a 6.8-fold higher ECL efficiency relative to the control AIDECL-active OD.Single-crystal studies and theoretical calculations reveal that the enhanced AIDECL behaviors come from the acceleration of both radiative transition and RISC.This work represents a major step towards purely organic,high-efficiency ECL dyes and a direction for the design of next-generation ECL dyes at the molecular level.展开更多
Simultaneously achieving high sensitivity and detection speed with traditional solid-state biosensors is usually limited since the target molecules must passively diffuse to the sensor surface before they can be detec...Simultaneously achieving high sensitivity and detection speed with traditional solid-state biosensors is usually limited since the target molecules must passively diffuse to the sensor surface before they can be detected.Microfluidic techniques have been applied to shorten the diffusion time by continuously moving molecules through the biosensing regions.However,the binding efficiencies of the biomolecules are still limited by the inherent laminar flow inside microscale channels.In this study,focused traveling surface acoustic waves were directed into an acoustic microfluidic chip,which could continuously enrich the target molecules into a constriction zone for immediate detection of the immune reactions,thus significantly improving the detection sensitivity and speed.To demonstrate the enhancement of biosensing,we first developed an acoustic microfluidic chip integrated with a focused interdigital transducer;this transducer had the ability to capture more than 91%of passed microbeads.Subsequently,polystyrene microbeads were pre-captured with human IgG molecules at different concentrations and loaded for detection on the chip.As representative results,~0.63,2.62,11.78,and 19.75 seconds were needed to accumulate significant numbers of microbeads pre-captured with human IgG molecules at concentrations of 100,10,1,and 0.1 ng/mL(~0.7 pM),respectively;this process was faster than the other methods at the hour level and more sensitive than the other methods at the nanomolar level.Our results indicated that the proposed method could significantly improve both the sensitivity and speed,revealing the importance of selective enrichment strategies for rapid biosensing of rare molecules.展开更多
Much effort has been made to uncover the cellular heterogeneities of human hearts by single-nucleus RNA sequencing.However,the cardiac transcriptional regulation networks have not been systematically described because...Much effort has been made to uncover the cellular heterogeneities of human hearts by single-nucleus RNA sequencing.However,the cardiac transcriptional regulation networks have not been systematically described because of the limitations in detecting transcription factors.In this study,we optimized a pipeline for isolating nuclei and conducting single-nucleus RNA sequencing targeted to detect a higher number of cell signal genes and an optimal number of transcription factors.With this unbiased protocol,we characterized the cellular composition of healthy human hearts and investigated the transcriptional regulation networks involved in determining the cellular identities and functions of the main cardiac cell subtypes.Particularly in fibroblasts,a novel regulator,PKNOX2,was identified as being associated with physiological fibroblast activation in healthy hearts.To validate the roles of these transcription factors in maintaining homeostasis,we used single-nucleus RNA-sequencing analysis of transplanted failing hearts focusing on fibroblast remodelling.The trajectory analysis suggested that PKNOX2 was abnormally decreased from fibroblast activation to pathological myofibroblast formation.Both gain-and loss-of-function in vitro experiments demonstrated the inhibitory role of PKNOX2 in pathological fibrosis remodelling.Moreover,fibroblast-specific overexpression and knockout of PKNOX2 in a heart failure mouse model induced by transverse aortic constriction surgery significantly improved and aggravated myocardial fibrosis,respectively.In summary,this study established a high-quality pipeline for single-nucleus RNA-sequencing analysis of heart muscle.With this optimized protocol,we described the transcriptional regulation networks of the main cardiac cell subtypes and identified PKNOX2 as a novel regulator in suppressing fibrosis and a potential therapeutic target for future translational studies.展开更多
Currently,enzyme-responsive nanomaterials have shown great promise in prognosis or diagnosis of disease biomarker.However,the great obstacle for conventional enzyme-responsive nanomaterials frequently lies in autofluo...Currently,enzyme-responsive nanomaterials have shown great promise in prognosis or diagnosis of disease biomarker.However,the great obstacle for conventional enzyme-responsive nanomaterials frequently lies in autofluorescence interference,poor monodispersity,uncontrollable size and morphology,low optical stability,and biotoxicity,which fundamentally impede their practical application in biological systems.To overcome these deficiencies,we proposed a novel strategy for reliable and precise detection of an enzyme disease biomarker,alkaline phosphatase(ALP),through lanthanide(Ln^(3+))nucleotide nanoparticles(LNNPs)with extremely improved monodispersity and uniformity,which were achieved by the coordination self-assembly between ATP and Ln^(3+)inside micellar nanoreactor.Specifically,for ATP-Ce/Tb LNNPs,highly improved photoluminescence(PL)emission of Tb^(3+)can be achieved via efficient Ce^(3+)sensitization.We demonstrated that ALP could specifically cleave the phosphorus–oxygen(P–O)bonds of ATP and result in the collapse of ATP-Ce/Tb scaffold,finally leading to the PL quenching of Tb^(3+).By taking advantage of time-resolved(TR)PL technique,the fabricated ATP-Ce/Tb LNNPs presented superior selectivity and sensitivity for the ALP bioassay in complicated serum samples,thus revealing the great potential of ATP-Ce/Tb LNNPs in the areas of ALP-related disease prognosis and diagnosis.展开更多
Chiral metal nanoclusters(MNCs)are competitive candidates for fabricating circularly polarized light-emitting diodes(CPLEDs),but the device performance is greatly limited by the poor emission of MNCs in solid thin fil...Chiral metal nanoclusters(MNCs)are competitive candidates for fabricating circularly polarized light-emitting diodes(CPLEDs),but the device performance is greatly limited by the poor emission of MNCs in solid thin films.Herein,host molecule enhanced aggregation induced emission(AIE)of MNCs is demonstrated for fabricating highly efficient CPLEDs.Namely,on the basis of the AIE effect of atomically precise enantiomeric(R/S)-4-phenylthiazolidine-2-thione capped silver(R/S-Ag_(6)(PTLT)_(6))NCs in solid thin films,1,3-bis(carbazol-9-yl)benzene(mCP)is introduced as a host molecule to control the orientation and packing arrangements of R/S-Ag_(6)(PTLT)_(6) NCs throughπ–πinteractions with the R/S-Ag_(6)(PTLT)_(6) NCs and further enhance the AIE.The as-fabricated Ag_(6)(PTLT)_(6) NC/mCP hybrid solid thin film shows a high photoluminescence quantum yield of 71.0%close to that of Ag_(6)(PTLT)_(6) NC single crystal.As the hybrid films are employed as the active emission layers of CPLEDs,mCP also suppresses the triplettriplet annihilation and balances the charge transport.Thus,the CPLEDs exhibit a maximum brightness of 3,906 cd/m^(2),peak external quantum efficiency of 10.0%,electroluminescence dissymmetry factors of−5.3×10^(−3)and 4.7×10^(−3).展开更多
Abrasive waterjet(AWJ)is widely applied in 2D machining as it offers high machining efficiency and low machining cost.However,machining a 3D surface,especially for a small curvature radius freeform surface(SCRFS),resu...Abrasive waterjet(AWJ)is widely applied in 2D machining as it offers high machining efficiency and low machining cost.However,machining a 3D surface,especially for a small curvature radius freeform surface(SCRFS),results in over-erosion of the corner,and has been one of the greatest issues of AWJ.To solve this problem,a local smoothing algorithm for SCRFS is developed by the junction of two linear segments at the corner by inserting cubic second-order B-spline to smooth the nozzle path and posture under the setting tolerance error,which is aimed to avoid over-erosion due to the change in dwell time.Analytical solutions of the smooth corner position and orientation of the nozzle path are obtained by evaluating a synchronization algorithm.According to the set tolerance error of the nozzle position and orientation,the interpolation of the smooth path of the corner meets the constraint conditions of the linear feed drive.Path simulation and experimental results show that the proposed method is validated by the experimental results and has been applied to the integral blisk machining of an aero-engine.展开更多
The Sulige tight gas field is presently the largest gas field in China.Owing to the ultralow permeability and strong heterogeneity of the reservoirs in Sulige,the number of production wells has exceeded 3,000,keeping ...The Sulige tight gas field is presently the largest gas field in China.Owing to the ultralow permeability and strong heterogeneity of the reservoirs in Sulige,the number of production wells has exceeded 3,000,keeping the stable gas supply in the decade.Thus,the daily production prediction of gas wells is significant for monitoring production and for implementing and evaluating stimulation measures.Therefore,on the basis of the three datadriven time series approaches,the daily production of 1692 wells over 10 years was mining for the daily production prediction of wells in Sulige.The jointed deep long short-term memory and fully connected neural network(DLSTM-FNN)model was proposed by introducing the recurrent neural network's sequential expression ability and was compared with random forest(RF)and support vector regression(SVR).After the daily production predictions of thousands of wells in Sulige,the proposed DLSTM-FNN model significantly improved the time series prediction accuracy and efficiency in the short training samples and had strong availability and practicability in the Sulige tight gas field.展开更多
An understanding of the nutrient utilization characteristics of pigs with different feed efficiencies(FEs) will help us to develop new strategies to reduce the costs of pig production.In this study,we selected pigs wi...An understanding of the nutrient utilization characteristics of pigs with different feed efficiencies(FEs) will help us to develop new strategies to reduce the costs of pig production.In this study,we selected pigs with a range of FEs according to two feed conversion ratio models: the feed intake(FI) model,where pigs had the same average daily gains(ADGs) but different FIs,and the ADG model,where pigs had the same FIs but different ADGs.High-FE pigs had a higher abundance of short chain fatty acid(SCFA)-producing bacteria(Lachnospiraceae,Clostridiaceae1,and Coriobacteriaceae) in their caecum in the FI model,and low-FE pigs had a higher abundance of two families(BacteroidalesS247group and Peptococcaceae) and two genera(Anaerotruncus and CandidatusSoleaferrea) in both models.By contrast,high-FE pigs had more goblet cells and higher m RNA expression of insulin-like growth factor 1(IGF-1) in the FI model,and higher mRNA expression of occludin but lower expressions of adenosine monophosphate-activated protein kinase(AMPK)-α2 and peroxisome proliferator-activated receptor gamma coactivator 1 alpha(PGC1α) in the ADG model.These findings suggest that the presence of SCFA-producing bacteria in the caecum and increased muscular growth may contribute to the high FE of low-FI pigs,while improved intestinal functions and decreased mitochondrial activity in the skeletal muscle are related to the high FE of high-ADG pigs.展开更多
基金The authors are grateful for the financial support from National Natural Science Foundation of China(32001728).
文摘Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic network on FAA biosynthesis remains unclear.Through metagenomic analysis,this work aimed to elucidate the roles of microbes in FAA biosynthesis during Monascus rice vinegar fermentation.Taxonomic profiles from functional analyses showed 14 dominant genera with high contributions to the metabolism pathways.The metabolic network for FAA biosynthesis was then constructed,and the microbial distribution in different metabolic pathways was illuminated.The results revealed that 5 functional genera were closely involved in FAA biosynthesis.This study illuminated the metabolic roles of microorganisms in FAA biosynthesis and provided crucial insights into the functional attributes of microbiota in vinegar fermentation.
基金The authors would like to acknowledge financial support from the National Key R&D Program of China(Nos.2021YFF1200700 and 2021YFA0911100)the National Natural Science Foundation of China(Nos.T2225010,32171399,and 32171456)+4 种基金the Fundamental Research Funds for the Central Universities,Sun Yat-Sen University(No.22dfx02)Pazhou Lab,Guangzhou(No.PZL2021KF0003)The authors also would like to thank the funding support from the Opening Project of Key Laboratory of Microelectronic Devices&Integrated Technology,Institute of Microelectronics,Chinese Academy of Sciences,and State Key Laboratory of Precision Measuring Technology and Instruments(No.pilab2211)QQOY would like to thank the China Postdoctoral Science Foundation(No.2022M713645)JL would like to thank the National Natural Science Foundation of China(No.62105380)and the China Postdoctoral Science Foundation(No.2021M693686).
文摘Modern medicine is increasingly interested in advanced sensors to detect and analyze biochemical indicators.Ion sensors based on potentiometric methods are a promising platform for monitoring physiological ions in biological subjects.Current semi-implantable devices are mainly based on single-parameter detection.Miniaturized semi-implantable electrodes for multiparameter sensing have more restrictions on the electrode size due to biocompatibility considerations,but reducing the electrode surface area could potentially limit electrode sensitivity.This study developed a semi-implantable device system comprising a multiplexed microfilament electrode cluster(MMEC)and a printed circuit board for real-time monitoring of intra-tissue K^(+),Ca^(2+),and Na^(+)concentrations.The electrode surface area was less important for the potentiometric sensing mechanism,suggesting the feasibility of using a tiny fiber-like electrode for potentiometric sensing.The MMEC device exhibited a broad linear response(K^(+):2–32 mmol/L;Ca^(2+):0.5–4 mmol/L;Na^(+):10–160 mmol/L),high sensitivity(about 20–45 mV/decade),temporal stability(>2weeks),and good selectivity(>80%)for the above ions.In vitro detection and in vivo subcutaneous and brain experiment results showed that the MMEC system exhibits good multi-ion monitoring performance in several complex environments.This work provides a platform for the continuous real-time monitoring of ion fluctuations in different situations and has implications for developing smart sensors to monitor human health.
基金Supported by Science Fund for Creative Research Groups of NSFC(51621064)National Natural Science Foundation of China(Grant No.51475074,11302043)the Fundamental Research Funds for the Central Universities(DUT15QY37)
文摘The integral impeller and blisk of an aero-engine are high performance parts with complex structure and made of difficult-to-cut materials. The blade surfaces of the integral impeller and blisk are functional surfaces for power transmission, and their surface integrity has signif- icant effects on the aerodynamic efficiency and service life of an aero-engine. Thus, it is indispensable to finish and strengthen the blades before use. This paper presents a comprehensive literature review of studies on finishing and strengthening technologies for the impeller and blisk of aero-engines. The review includes independent and inte- grated finishing and strengthening technologies and dis- cusses advanced rotational abrasive flow machining with back-pressure used for finishing the integral impeller and blisk. A brief assessment of future research problems and directions is also presented.
基金financially supported by the Science Foundation of China University of Petroleum,Beijing(2462017YJRC048,2462018BJC005)the National Natural Science Foundation of China(51802351)~~
文摘The surface plasmonic resonance(SPR)effect of Bi can effectively improve the light absorption abilities and photogenerated charge carrier separation rate.In this study,a novel ternary heterojunction of g-C3N4/Bi2MoO6/Bi(CN/BMO/Bi)hollow microsphere was successfully fabricated through solvothermal and in situ reduction methods.The results revealed that the optimal ternary 0.4 CN/BMO/9 Bi photocatalyst exhibited the highest photocatalytic efficiency toward rhodamine B(RhB)degradation with nine times that of pure BMO.The DRS and valence band of the X-ray photoelectron spectroscopy spectrum demonstrate that the band structure of 0.4 CN/BMO/9 Bi is a z-scheme structure.Quenching experiments also provided solid evidence that the·O^2-(at-0.33 eV)is the main species during dye degradation,and the conduction band of g-C3N4 is only the reaction site,demonstrating that the transfer of photogenerated charge carriers of g-C3N4/Bi2 MoO 6/Bi is through an indirect z-scheme structure.Thus,the enhanced photocatalytic performance was mainly ascribed to the synergetic effect of heterojunction structures between g-C3N4 and Bi2MoO6 and the SPR effect of Bi doping,resulting in better optical absorption ability and a lower combination rate of photogenerated charge carriers.The findings in this work provide insight into the synergism of heterostructures and the SPR absorption ability in wastewater treatment.
基金This work is supported by the Aeronautical Science Foundation of China under Grant 20165515001the National Natural Science Foundation of China under Grant No.61402225State Key Laboratory for smart grid protection and operation control Foundation,and the Science and Technology Funds from National State Grid Ltd.(The Research on Key Technologies of Distributed Parallel Database Storage and Processing based on Big Data).
文摘Tiered Mobile Wireless Sensor Network(TMWSN)is a new paradigm introduced by mobile edge computing.Now it has received wide attention because of its high scalability,robustness,deployment flexibility,and it has a wide range of application scenarios.In TMWSNs,the storage nodes are the key nodes of the network and are more easily captured and utilized by attackers.Once the storage nodes are captured by the attackers,the data stored on them will be exposed.Moreover,the query process and results will not be trusted any more.This paper mainly studies the secure KNN query technology in TMWSNs,and we propose a secure KNN query algorithm named the Basic Algorithm For Secure KNN Query(BAFSKQ)first,which can protect privacy and verify the integrity of query results.However,this algorithm has a large communication overhead in most cases.In order to solve this problem,we propose an improved algorithm named the Secure KNN Query Algorithm Based on MR-Tree(SEKQAM).The MR-Trees are used to find the K-nearest locations and help to generate a verification set to process the verification of query results.It can be proved that our algorithms can effectively guarantee the privacy of the data stored on the storage nodes and the integrity of the query results.Our experimental results also show that after introducing the MR-Trees in KNN queries on TMWSNs,the communication overhead has an effective reduction compared to BAFSKQ.
基金the National Natural Science Foundation of China, No. 30770755
文摘The human immunodeficiency virus （HIV） lentiviral vector is an ideal vector for gene therapy. In the present study, the wild-type HIV-1 genome was segregated into four plasmids, and an optimized novel HIV-1 lentiviral vector containing green fluorescent protein and vesicular stomatitis virus G pseudo-capsule was constructed. The plasmids were pHR-CMV-EGFP, pCMVΔ8.9, pRSV-Rev, pCMV-VSV-G. The four plasmid system was co-transfected into 293T cells, and green fluorescent protein expression was observed. The present study obtained lentiviral particles by high-speed centrifugation, and the lentiviral particle titer was 4 × 108 TU/mL after centrifugation. Thus, an optimized novel HIV-1 lentiviral vector was successfully constructed.
文摘Objective To investigate the etiology and relative factors of dilated cardiomyopathy （DCM） in Chinese patients. Methods A case-control study was conducted to compare 233 patients with DCM in high-incidence areas （case group） and 150 patients with stable angina pectoris （control group）. Life styles and history of diseases information was collected by questionaire; human anti-myocardial antibody lgG （AMA- IgG）, human Coxsackie B virus IgG （CBV- IgG） and human adenovirus antibody IgG （ADV- IgG） were measured with ELISA. General chemical and toxicological indicators in drink water from high and low prevalence areas and serum trace elements also were compared. Results 1） Compared with the control group, the case group had more farmers （P 〈 0.01）, with low average incomes （P 〈 0.01 ）, higher alcohol consumption （P 〈 0.01） and higher incidence of the history of myocarditis （P 〈 0.01）. 2） AMA-IgG, CBV-IgG and ADV-IgG levels were low and the positive rates ofAMA-IgG, CBV-IgG and ADV-IgG of patients with DCM were respectively 7.78%, 6.67% and 6.67%, no statistical significance comparing with those in the control group. 3） The content of iron （1.36±2.18 vs 0.39±0.67 rag/L, P〈0.05） and manganese （0.38±0.35 vs 0.15±0.14, P〈0.01） in drinking water of high-incidence areas was significantly higher than that in low-incidence areas. 4） The content of serum iron （69.1±57.8 vs 20.0±17.5 umol/L, P〈0.01 ） and copper （25.7±4.2 vs 19.7±4.5 umol/L, P〈0.01） in the case group evidently exceeded the normal range and obviously higher than that in the control group. Conclusions 1） The incidence of some DCM is related with low incomes, high alcohol consumption and myoearditis. 2） These data do not support that DCM is related with persistent virus infection and autoimmunization; 3） Iron and manganese contents exceeding standards in drinking water and the high content of serum iron and copper is comparatively related with the incidence of DCM.
基金funded by the National Natural Science Foundation of China(Grant No.51135002)Science Fund for Creative Research Groups of NSFC(Grant No.51621064)。
文摘Large-sized potassium dihydrogen phosphate(KDP)crystals are an irreplaceable nonlinear optical component in an inertial confinement fusion project.Restricted by the size,previous studies have been aimed mainly at the removal principle and surface roughness of small-sized KDP crystals,with less research on flatness.Due to its low surface damage and high machining efficiency,water dissolution ultraprecision continuous polishing(WDUCP)has become a good technique for processing large-sized KDP crystals.In this technique,the trajectory uniformity of water droplets can directly affect the surface quality,such as flatness and roughness.Specifically,uneven trajectory distribution of water droplets on the surface of KDP crystals derived from the mode of motion obviously affects the surface quality.In this study,the material removal mechanism of WDUCP was introduced.A simulation of the trajectory of water droplets on KDP crystals under different eccentricity modes of motion was then performed.Meanwhile,the coefficient of variation(CV)was utilized to evaluate the trajectory uniformity.Furthermore,to verify the reliability of the simulation,some experimental tests were also conducted by employing a large continuous polisher.The results showed that the CV varied from 0.67 to 2.02 under the certain eccentricity mode of motion and varied from 0.48 to 0.65 under the uncertain eccentricity mode of motion.The CV of uncertain eccentricity is always smaller than that of certain eccentricity.Hence,the uniformity of trajectory was better under uncertain eccentricity.Under the mode of motion of uncertain eccentricity,the initial surface texture of the100 mm×100 mm×10 mm KDP crystal did achieve uniform planarization.The surface root mean square roughness was reduced to 2.182 nm,and the flatness was reduced to 22.013μm.Therefore,the feasibility and validity of WDUCP for large-sized KDP crystal were verified.
基金This work was supported by the National Natural Science Foundation of China(NSFC)[grant nos.51605076,51875079]the Fundamental Research Funds for the Central Universities[grant no.DUT18LAB18].
文摘The hot pressing process parameters were optimized to prepare flax fiber reinforced polyethylene(PE)thermoplastic composite by the Taguchi method.The optimal hot pressing process parameters were determined to increase the tensile strength of the composite.The optimal parameters of the design include the following sections:hot pressing temperature,pressure,hot pressing time and coupling agent modification time.An L9(3*4)orthogonal matrix based on the Taguchi method was created.By means of analysis of signal-to-noise ratio and analysis of variance,the optimal hot pressing process parameters combination was found,compared to the average tensile strength in the nine design experiments,and the tensile strength was improved nearly 10%.
基金National Natural Science Foundation of China,Grant/Award Numbers:22034003,22204075,22275085Natural Science Foundation of Jiangsu Province,Grant/Award Number:BK20220769+1 种基金Excellent Research Program of Nanjing University,Grant/Award Number:ZYJH004State Key Laboratory of Analytical Chemistry for Life Science,Grant/Award Number:5431ZZXM2203。
文摘Full utilization of the excited species at both singlet states(1R*)and triplet states(3R*)is crucial to improving electrochemiluminescence(ECL)efficiency but is challenging for organic luminescent materials.Here,an aggregation-induced delayed ECL(AIDECL)active organic dot(OD)containing a benzophenone acceptor and dimethylacridine donor is reported,which shows high ECL efficiency via reverse intersystem crossing(RISC)of non-emissive 3R*to emissive 1R*,overcoming the spin-forbidden radiative decay from 3R*.By introducing dual donor-acceptor pairs into luminophores,it is found that nonradiative pathway could be further suppressed via enhanced intermolecular weak interactions,and multiple spin-up conversion channels could be activated.As a consequence,the obtained OD enjoys a 6.8-fold higher ECL efficiency relative to the control AIDECL-active OD.Single-crystal studies and theoretical calculations reveal that the enhanced AIDECL behaviors come from the acceleration of both radiative transition and RISC.This work represents a major step towards purely organic,high-efficiency ECL dyes and a direction for the design of next-generation ECL dyes at the molecular level.
基金supported by the National Key Research and Development Program of China(No.2022YFB3207200)the National Natural Science Foundation of China(Nos.62171441,62104248).
文摘Simultaneously achieving high sensitivity and detection speed with traditional solid-state biosensors is usually limited since the target molecules must passively diffuse to the sensor surface before they can be detected.Microfluidic techniques have been applied to shorten the diffusion time by continuously moving molecules through the biosensing regions.However,the binding efficiencies of the biomolecules are still limited by the inherent laminar flow inside microscale channels.In this study,focused traveling surface acoustic waves were directed into an acoustic microfluidic chip,which could continuously enrich the target molecules into a constriction zone for immediate detection of the immune reactions,thus significantly improving the detection sensitivity and speed.To demonstrate the enhancement of biosensing,we first developed an acoustic microfluidic chip integrated with a focused interdigital transducer;this transducer had the ability to capture more than 91%of passed microbeads.Subsequently,polystyrene microbeads were pre-captured with human IgG molecules at different concentrations and loaded for detection on the chip.As representative results,~0.63,2.62,11.78,and 19.75 seconds were needed to accumulate significant numbers of microbeads pre-captured with human IgG molecules at concentrations of 100,10,1,and 0.1 ng/mL(~0.7 pM),respectively;this process was faster than the other methods at the hour level and more sensitive than the other methods at the nanomolar level.Our results indicated that the proposed method could significantly improve both the sensitivity and speed,revealing the importance of selective enrichment strategies for rapid biosensing of rare molecules.
基金supported by the National Natural Science Foundation of China(82100377)National High Level Hospital Clinical Research Funding(2023-GSP-RC-01,2023-GSP-ZD-2)the Beijing Nova Program(Z211100002121046,20220484205).Figure 10 was created with BioRender.com.
文摘Much effort has been made to uncover the cellular heterogeneities of human hearts by single-nucleus RNA sequencing.However,the cardiac transcriptional regulation networks have not been systematically described because of the limitations in detecting transcription factors.In this study,we optimized a pipeline for isolating nuclei and conducting single-nucleus RNA sequencing targeted to detect a higher number of cell signal genes and an optimal number of transcription factors.With this unbiased protocol,we characterized the cellular composition of healthy human hearts and investigated the transcriptional regulation networks involved in determining the cellular identities and functions of the main cardiac cell subtypes.Particularly in fibroblasts,a novel regulator,PKNOX2,was identified as being associated with physiological fibroblast activation in healthy hearts.To validate the roles of these transcription factors in maintaining homeostasis,we used single-nucleus RNA-sequencing analysis of transplanted failing hearts focusing on fibroblast remodelling.The trajectory analysis suggested that PKNOX2 was abnormally decreased from fibroblast activation to pathological myofibroblast formation.Both gain-and loss-of-function in vitro experiments demonstrated the inhibitory role of PKNOX2 in pathological fibrosis remodelling.Moreover,fibroblast-specific overexpression and knockout of PKNOX2 in a heart failure mouse model induced by transverse aortic constriction surgery significantly improved and aggravated myocardial fibrosis,respectively.In summary,this study established a high-quality pipeline for single-nucleus RNA-sequencing analysis of heart muscle.With this optimized protocol,we described the transcriptional regulation networks of the main cardiac cell subtypes and identified PKNOX2 as a novel regulator in suppressing fibrosis and a potential therapeutic target for future translational studies.
基金supported by the National Key R&D Program of China(No.2022YFB3503700)the National Natural Science Foundation of China(NSFC)(Nos.22135008,U22A20398,and 22275190)+1 种基金the Natural Science Foundation of Fujian Province(Nos.2021L3024,2021Y0067)the Open Fund of State Key Laboratory of Structural Chemistry(No.20210023).
文摘Currently,enzyme-responsive nanomaterials have shown great promise in prognosis or diagnosis of disease biomarker.However,the great obstacle for conventional enzyme-responsive nanomaterials frequently lies in autofluorescence interference,poor monodispersity,uncontrollable size and morphology,low optical stability,and biotoxicity,which fundamentally impede their practical application in biological systems.To overcome these deficiencies,we proposed a novel strategy for reliable and precise detection of an enzyme disease biomarker,alkaline phosphatase(ALP),through lanthanide(Ln^(3+))nucleotide nanoparticles(LNNPs)with extremely improved monodispersity and uniformity,which were achieved by the coordination self-assembly between ATP and Ln^(3+)inside micellar nanoreactor.Specifically,for ATP-Ce/Tb LNNPs,highly improved photoluminescence(PL)emission of Tb^(3+)can be achieved via efficient Ce^(3+)sensitization.We demonstrated that ALP could specifically cleave the phosphorus–oxygen(P–O)bonds of ATP and result in the collapse of ATP-Ce/Tb scaffold,finally leading to the PL quenching of Tb^(3+).By taking advantage of time-resolved(TR)PL technique,the fabricated ATP-Ce/Tb LNNPs presented superior selectivity and sensitivity for the ALP bioassay in complicated serum samples,thus revealing the great potential of ATP-Ce/Tb LNNPs in the areas of ALP-related disease prognosis and diagnosis.
基金the National Natural Science Foundation of China(Nos.21902057 and 21773088)the China Postdoctoral Science Foundation(No.2021M691201)+1 种基金the Interdisciplinary Scientific Research Team Project of Jilin University(No.419021420367)the Special Project from MOST of China.
文摘Chiral metal nanoclusters(MNCs)are competitive candidates for fabricating circularly polarized light-emitting diodes(CPLEDs),but the device performance is greatly limited by the poor emission of MNCs in solid thin films.Herein,host molecule enhanced aggregation induced emission(AIE)of MNCs is demonstrated for fabricating highly efficient CPLEDs.Namely,on the basis of the AIE effect of atomically precise enantiomeric(R/S)-4-phenylthiazolidine-2-thione capped silver(R/S-Ag_(6)(PTLT)_(6))NCs in solid thin films,1,3-bis(carbazol-9-yl)benzene(mCP)is introduced as a host molecule to control the orientation and packing arrangements of R/S-Ag_(6)(PTLT)_(6) NCs throughπ–πinteractions with the R/S-Ag_(6)(PTLT)_(6) NCs and further enhance the AIE.The as-fabricated Ag_(6)(PTLT)_(6) NC/mCP hybrid solid thin film shows a high photoluminescence quantum yield of 71.0%close to that of Ag_(6)(PTLT)_(6) NC single crystal.As the hybrid films are employed as the active emission layers of CPLEDs,mCP also suppresses the triplettriplet annihilation and balances the charge transport.Thus,the CPLEDs exhibit a maximum brightness of 3,906 cd/m^(2),peak external quantum efficiency of 10.0%,electroluminescence dissymmetry factors of−5.3×10^(−3)and 4.7×10^(−3).
基金supported by NSFC-Liaoning Joint Fund(Grant Nos.U1708256,U1908232)Fundamental Research Funds for the Central Universities(Grant No.DUT18GF104)Joint Fund of MOE and GAD(Grant No.6141A02022133).
文摘Abrasive waterjet(AWJ)is widely applied in 2D machining as it offers high machining efficiency and low machining cost.However,machining a 3D surface,especially for a small curvature radius freeform surface(SCRFS),results in over-erosion of the corner,and has been one of the greatest issues of AWJ.To solve this problem,a local smoothing algorithm for SCRFS is developed by the junction of two linear segments at the corner by inserting cubic second-order B-spline to smooth the nozzle path and posture under the setting tolerance error,which is aimed to avoid over-erosion due to the change in dwell time.Analytical solutions of the smooth corner position and orientation of the nozzle path are obtained by evaluating a synchronization algorithm.According to the set tolerance error of the nozzle position and orientation,the interpolation of the smooth path of the corner meets the constraint conditions of the linear feed drive.Path simulation and experimental results show that the proposed method is validated by the experimental results and has been applied to the integral blisk machining of an aero-engine.
基金Supported by the National Key R&D Program of China(2020YFA0713404).
文摘The Sulige tight gas field is presently the largest gas field in China.Owing to the ultralow permeability and strong heterogeneity of the reservoirs in Sulige,the number of production wells has exceeded 3,000,keeping the stable gas supply in the decade.Thus,the daily production prediction of gas wells is significant for monitoring production and for implementing and evaluating stimulation measures.Therefore,on the basis of the three datadriven time series approaches,the daily production of 1692 wells over 10 years was mining for the daily production prediction of wells in Sulige.The jointed deep long short-term memory and fully connected neural network(DLSTM-FNN)model was proposed by introducing the recurrent neural network's sequential expression ability and was compared with random forest(RF)and support vector regression(SVR).After the daily production predictions of thousands of wells in Sulige,the proposed DLSTM-FNN model significantly improved the time series prediction accuracy and efficiency in the short training samples and had strong availability and practicability in the Sulige tight gas field.
基金supported by the National Natural Science Foundation of China(31630074)the Beijing Municipal Natural Science Foundation(S170001)+2 种基金the National Key Research and Development Program of China(2016YFD0500506)the 111 Project(B16044)Jinxinnong Animal Science Developmental Foundation and Hunan Co-Innovation Center of Animal Production Safety
文摘An understanding of the nutrient utilization characteristics of pigs with different feed efficiencies(FEs) will help us to develop new strategies to reduce the costs of pig production.In this study,we selected pigs with a range of FEs according to two feed conversion ratio models: the feed intake(FI) model,where pigs had the same average daily gains(ADGs) but different FIs,and the ADG model,where pigs had the same FIs but different ADGs.High-FE pigs had a higher abundance of short chain fatty acid(SCFA)-producing bacteria(Lachnospiraceae,Clostridiaceae1,and Coriobacteriaceae) in their caecum in the FI model,and low-FE pigs had a higher abundance of two families(BacteroidalesS247group and Peptococcaceae) and two genera(Anaerotruncus and CandidatusSoleaferrea) in both models.By contrast,high-FE pigs had more goblet cells and higher m RNA expression of insulin-like growth factor 1(IGF-1) in the FI model,and higher mRNA expression of occludin but lower expressions of adenosine monophosphate-activated protein kinase(AMPK)-α2 and peroxisome proliferator-activated receptor gamma coactivator 1 alpha(PGC1α) in the ADG model.These findings suggest that the presence of SCFA-producing bacteria in the caecum and increased muscular growth may contribute to the high FE of low-FI pigs,while improved intestinal functions and decreased mitochondrial activity in the skeletal muscle are related to the high FE of high-ADG pigs.
