The undeformed chip thickness and grinding force are key parameters for revealing the material removal mechanism in the grinding process.However,they are difficult to be well expressed due to the ununiformed protrusio...The undeformed chip thickness and grinding force are key parameters for revealing the material removal mechanism in the grinding process.However,they are difficult to be well expressed due to the ununiformed protrusion height and random position distribution of abrasive grains on the abrasive wheel surface.This study investigated the distribution of undeformed chip thickness and grinding force considering the non-uniform characteristics of abrasive wheel in the grinding of K4002 nickel-based superalloy.First,a novel grinding force model was established through a kinematic-geometric analysis and a grain-workpiece contact analysis.Then,a series of grinding experiments were conducted for verifying the model.The results indicate that the distribution of undeformed chip thickness is highly consistent with the Gaussian distribution formula.The increase in the grinding depth mainly leads to an increase in the average value of Gaussian distribution.On the contrary,the increase in the workpiece infeed speed or the decrease in the grinding speed mainly increases the standard deviation of Gaussian distribution.The average and maximum errors of the grinding force model are 4.9%and 14.6%respectively,indicating that the model is of high predication accuracy.展开更多
Pre-harvest sprouting(PHS)describes the germination of physiologically mature grains in spikes prior to harvest in cereal crops.PHS could seriously decrease grain yield and quality,which makes it a major constraint to...Pre-harvest sprouting(PHS)describes the germination of physiologically mature grains in spikes prior to harvest in cereal crops.PHS could seriously decrease grain yield and quality,which makes it a major constraint to cereal production worldwide.A number of PHS-associated genes in cereals have been reported;however,the molecular mechanisms underlying PHS remain largely elusive.Here,we report a CRISPRCas9 mutant with severe PHS in a paddy field.The mutated gene OsMFT2 encodes a phosphatidylethanolamine-binding protein(PEBP).Intriguingly,the OsMFT1,in the same PEBP family,had the opposite effect in controlling rice PHS as does OsMFT2.Germination tests of seeds of chimeric protein-expressing plants revealed that the fourth exon conferred the antagonistic activity of OsMFT1 and OsMFT2 in rice PHS.Additionally,two lines of these plants showed elevated grain numbers per panicle,implying that chimeric protein has potential to significantly increase yield.Moreover,transcriptome analysis and genetic studies indicated that OsMFT1 and OsMFT2 performed opposing functions in rice PHS owing to three co-regulated genes that being contrastingly affected by OsMFT1 and OsMFT2.Overall,it seemed that the proper combination of PEBP family members could obtain optimal PHS resistance and high yield.展开更多
ZnO thin films with varying Ta concentrations were fabricated through magnetron sputtering.The crystallinity and surface morphology of the ZnO films are significantly influenced by the incorporation of Ta,as evidenced...ZnO thin films with varying Ta concentrations were fabricated through magnetron sputtering.The crystallinity and surface morphology of the ZnO films are significantly influenced by the incorporation of Ta,as evidenced by the X-ray diffraction and scanning electron microscopy results.The lattice constants,as determined by X-ray diffraction,contradict the disparity in Ta and Zn ion radii,which is attributed to the impact of interstitial defects.This inconsistency introduces variations in carrier concentration in this experiment compared with prior studies.Subsequent exploration of the luminescent characteristics and emission mechanism of defect levels in Ta-doped ZnO films was conducted through photoluminescence.Furthermore,the factors influencing the bandgap are discussed.展开更多
Fluorine(F)-enriched soils,resulting from geogenic processes or superimposed by anthropogenic activities,have raised significant concerns due to their phytotoxicity and potential threats to human health.Soils in centr...Fluorine(F)-enriched soils,resulting from geogenic processes or superimposed by anthropogenic activities,have raised significant concerns due to their phytotoxicity and potential threats to human health.Soils in central Guizhou Province exhibit F enrichment,with a mean F concentration of 1067 mg/kg.However,the associated human health risks and geochemical mechanisms driving F enrichment in these soils remain insufficiently understood.In areas with a natural geological background,the average concentrations of F in rice,vegetables,drinking water,and ambient air are 1.54 mg/kg,0.54 mg/kg,0.16 mg/L,and 0.29μg/m^(3),respectively.In contrast,samples collected near phosphorous chemical plants demonstrate elevated F concentrations:1.78 mg/kg in rice,1.53 mg/kg in vegetables,0.20 mg/L in drinking water,and 11.98μg/m^(3) in ambient air.Fluorine in soils was immobilized by apatite and clay minerals,and hardly transferred into water and crops.The fixation of F-by Ca^(2+)in water and by Fe/Al hydroxides and clay minerals in bottom sediment further reduces F concentrations in water.As a result,hazard quotient(HQ)values below 1.0 indicate negligible fluorine-related health risk in geological background regions.However,ambient air near phosphorous chemical plant exhibited a 41.3-fold increase in F concentration compared to geological background regions.Fluorine-laden emissions can be directly inhaled or deposited on vegetable leaves and orally ingested into human bodies.Improvement of F-rich waste gas disposal and restricted leafy vegetable cultivation are effective measures to reduce F health risks in phosphorous chemical plant regions.展开更多
Xining,a river valley city in China’s arid region,serves as an important industrial hub with a fragile ecological environment.While groundwater heavy metal pollution in this area has drawn increasing concern,the sour...Xining,a river valley city in China’s arid region,serves as an important industrial hub with a fragile ecological environment.While groundwater heavy metal pollution in this area has drawn increasing concern,the sources and associated human health risks remain inadequately understood.This study analyzed 144 shallow groundwater samples from urban Xining for 14 heavy metals(Fe,Al,B,Mn,Ba,Zn,Pb,Cr^(6+),Ni,Cu,Co,Sb,Cd,and As)using the Nemerow comprehensive pollution index,correlation analysis,and the USEPA health risk assessment model.Results identified Fe,Al,B,Mn,Ba,Pb,Cd,and As as the primary pollutants,especially concentrated in river valley plains.These contaminants primarily originate from natural sedimentary conditions and human activities such as industrial and agricultural development.The pollution indices for Al,Pb,Mn,and Fe exceeded clean water thresholds,indicating serious contamination and the need for enhanced regulation.Health risk assessments revealed that children face greater exposure risks than adults,with arsenic and nickel being the main contributors to carcinogenic risk.Sensitivity analysis further showed that As,Fe,and Cd posed the greatest non-carcinogenic and carcinogenic risks,particularly in human-impacted areas such as the Nanchuan and Beichuan valleys and Ganhegou.These findings provide essential insights for groundwater safety management in plateau river valley cities and similar vulnerable regions.展开更多
Predicting monsoon climate is one of the major endeavors in climate science and is becoming increasingly challenging due to global warming. The accuracy of monsoon seasonal predictions significantly impacts the lives ...Predicting monsoon climate is one of the major endeavors in climate science and is becoming increasingly challenging due to global warming. The accuracy of monsoon seasonal predictions significantly impacts the lives of billions who depend on or are affected by monsoons, as it is essential for the water cycle, food security, ecology, disaster prevention, and the economy of monsoon regions. Given the extensive literature on Asian monsoon climate prediction, we limit our focus to reviewing the seasonal prediction and predictability of the Asian Summer Monsoon (ASM). However, much of this review is also relevant to monsoon predictions in other seasons and regions. Over the past two decades, considerable progress has been made in the seasonal forecasting of the ASM, driven by an enhanced understanding of the sources of predictability and the dynamics of seasonal variability, along with advanced development in sophisticated models and technologies. This review centers on advances in understanding the physical foundation for monsoon climate prediction (section 2), significant findings and insights into the primary and regional sources of predictability arising from feedback processes among various climate components (sections 3 and 4), the effects of global warming and external forcings on predictability (section 5), developments in seasonal prediction models and techniques (section 6), the challenges and limitations of monsoon climate prediction (section 7), and emerging research trends with suggestions for future directions (section 8). We hope this review will stimulate creative activities to enhance monsoon climate prediction.展开更多
For an improved understanding of gas enrichment mechanism in the eastern Sichuan Basin,South China,twelve natural gas samples were obtained from carbonate reservoirs of the Upper Permian strata to analyze the hydrocar...For an improved understanding of gas enrichment mechanism in the eastern Sichuan Basin,South China,twelve natural gas samples were obtained from carbonate reservoirs of the Upper Permian strata to analyze the hydrocarbon and non-hydrocarbon gas compositions,stable carbon and hydrogen isotopes ratios of hydrocarbons,and noble gas isotope ratios.The gas samples in the Upper Permian reservoirs principally consist of alkane gas with a dryness ratio ranging from 127.9 to 1564.4.The carbon isotope ratio of methane(δ^(13)C_(1))was almost constant at-34.1 to-31.3‰,but the carbon isotope ratio of ethane(δ^(13)C2)varied from-36.6‰to-25.8‰.The hydrogen isotope ratio of methane(δ^2HC_(1))also displayed a wide range from-137‰to-127‰.The large variations in the dryness ratio,δ^(13)C_(2),andδ^2HC_(1)with almost constantδ^(13)C_(1)suggest the mixing of sapropelic and humic origins for hydrocarbon gases in these reservoirs.A high concentration of hydrogen sulfide(H_(2)S)originated from the thermochemical sulfate reduction(TSR),which was positively correlated withδ^(13)C_(1)(orδ^(13)C_(2))in individual gas fields.TSR alteredδ^(13)C_(1)(orδ^(13)C_(2))and resulted in the abnormal character of isotopic reversal in the individual samples.Theδ^(13)C_(1)(orδ^(13)C_(2))in most gas samples,independent of H_(2)S concentration,further displayed reversed carbon isotopes because of the mixture of thermogenic gases with various thermal maturity levels.The measured argon isotope ratio(^(40)Ar/^(36)Ar)varied from 310 to 1225,which suggests that the oldest 320 Ma source rock age corresponds to Permian shales.The analysis of the gas origin and the identification of primary source rock have made a significant contribution to further understanding the resource potential and distribution of natural gas in the Upper Permian,and have great implications for gas exploration in the eastern Sichuan Basin.展开更多
BACKGROUND Postoperative delirium(POD)is a concerning complication of organ transplantation.With organ transplantation offering hope to patients with end-stage organ disease,understanding the incidence and risk factor...BACKGROUND Postoperative delirium(POD)is a concerning complication of organ transplantation.With organ transplantation offering hope to patients with end-stage organ disease,understanding the incidence and risk factors of POD is crucial,as it can significantly affect patients’prognosis and healthcare costs.AIM To systematically evaluate the incidence and risk factors of POD following organ transplantation to facilitate clinical prevention and optimize patient management and prognosis.METHODS Multiple databases such as PubMed and their reference lists were comprehensively searched using a combination of keywords related to organ transplantation and POD.Relevant observational studies on patients who had undergone solid organ transplantation and randomized controlled trials containing relevant analyses were included.Duplicated,data-deficient,non-English,and non-original data studies were excluded.Data were extracted independently by two researchers and then cross-checked.The Newcastle-Ottawa scale was used to evaluate the quality of the included studies.RevMan 5.3 was employed for data analysis.The pooled incidence of POD was calculated according to the data type,and the fixed or random effect model was employed to analyze risk factors based on heterogeneity.Subsequently,sensitivity analysis and publication bias assessments were performed.RESULTS A total of 39 relevant literatures were included.The overall incidence of POD in the organ transplant group was 20%[95%confidence interval(CI):18%-22%];liver transplant group,22%(95%CI:17%-26%);lung transplant group,34%(95%CI:23%-45%);and kidney transplant group,6%(95%CI:2%-10%).Primary graft dysfunction increased the POD risk,with a pooled odds ratio(OR)(95%CI)of 1.78(1.09-2.91).A history of hepatic encephalopathy increased the POD risk,with a pooled OR(95%CI)of 3.19(2.30-4.43).The higher the Acute Physiology and Chronic Health Evaluation II score,the greater the POD risk,with a pooled OR(95%CI)of 1.52(1.09-2.12).A history of alcohol abuse increased the POD risk,with a pooled OR(95%CI)of 2.84(1.74-4.65).Thus,the higher the model for end-stage liver disease score,the greater the POD risk,with a pooled OR(95%CI)of 2.49(1.14-5.43).POD was more likely to develop in patients with preoperative infections,with a pooled OR(95%CI)of 2.78(1.56-4.97).The use of diuretics increased the POD risk,with a pooled OR(95%CI)of 2.36(1.38-4.04).CONCLUSION In this study,the overall incidence of POD in patients who underwent organ transplantation is 20%.The incidence varies among different types of organ transplantation,and multiple factors can increase the POD risk.展开更多
BACKGROUND Gastric cancer(GC)is among the most common malignant tumors and remains a leading cause of cancer-related mortality worldwide.Furthermore,exosomal miRNAs are regarded as promising noninvasive biomarkers for...BACKGROUND Gastric cancer(GC)is among the most common malignant tumors and remains a leading cause of cancer-related mortality worldwide.Furthermore,exosomal miRNAs are regarded as promising noninvasive biomarkers for diagnosing malignant tumors.AIM To investigate the expression of exosomal miR-17-92 clusters and develop a potential biomarker for GC diagnosis METHODS Exosomes were isolated from serum samples obtained from 72 GC patients and 20 healthy controls.The isolated exosomes were validated using transmission electron microscopy,nanoparticle tracking analysis,and western blotting.Exosomal RNA was then extracted,and the expression profile of the miR-17-92 cluster was analyzed using qRT-PCR.Statistical methods were employed to evaluate the relationship between the serum exosomal miR-17-92 cluster expre-ssion and the clinicopathological parameters of GC patients as well as to assess the diagnostic utility of these miRNAs.RESULTS The expression of four members of the exosomal miR-17-92 cluster-miR-17,miR-18,miR-19a,and miR-92-was significantly upregulated in the serum samples of patients with GC compared with those of healthy controls.The miR-17-92 cluster panel demonstrated substantially higher clinical diagnostic value for GC than any individual component or pair.Additionally,the expression of traditional tumor biomarkers-carcinoembryonic antigen and carbohydrate antigen 19-9-was significantly elevated in the serum of patients with GC compared with that of healthy controls.Each biomarker,whether alone or in combination,effectively differentiated the patients from healthy controls.Furthermore,a combined panel of the two traditional tumor biomarkers and the four miR-17-92 cluster members exhibited the highest diagnostic accuracy for GC.Elevated miR-17-92 expression was also strongly associated with tumor size,tumor depth,lymph node metastasis,distant metastasis,and tumor-node-metastasis stage.CONCLUSION Our findings revealed that the circulating exosomal miR-17-92 cluster may be used as a potential noninvasive biomarker to improve diagnostic efficiency for GC.展开更多
The dynamic mechanical response and deformation mechanism of magnesium-yttrium alloy at high strain rate were investigated using split-Hopkinson pressure bar(SHPB)impact,and the microstructure evolution and crack form...The dynamic mechanical response and deformation mechanism of magnesium-yttrium alloy at high strain rate were investigated using split-Hopkinson pressure bar(SHPB)impact,and the microstructure evolution and crack formation mechanism were revealed.The yield strength and work hardening rate increase significantly with increasing impact strain rate.Deformation twinning and non-basal dislocation slip are the primary deformation mechanisms during testing.Contrary to crack initiation mechanism facilitated by adiabatic shear bands,we find that high-density co-axial nanocrystalline grains form near cracks,which leads to local softening and promotes crack initiation and rapid propagation.Most grains have similar<1^(-)21^(-)0>orientations,with unique misorientation of 24°,32°,62°,78°and 90°between adjacent grains,suggesting that these grains are primarily formed by interface transformation,which exhibits distinct differences from recrystallized grains.Our results shed light upon the dynamic mechanical response and crack formation mechanism in magnesium alloys under impact deformation.展开更多
Based on the C-Coupler platform,the semi-unstructured Climate System Model,Synthesis Community Integrated Model version 2(SYCIM2.0),has been developed at the School of Atmospheric Sciences,Sun Yat-sen University.SYCIM...Based on the C-Coupler platform,the semi-unstructured Climate System Model,Synthesis Community Integrated Model version 2(SYCIM2.0),has been developed at the School of Atmospheric Sciences,Sun Yat-sen University.SYCIM2.0 aims to meet the demand for seamless climate prediction through accurate climate simulations and projections.This paper provides an overview of SYCIM2.0 and highlights its key features,especially the coupling of an unstructured ocean model and the tuning process.An extensive evaluation of its performance,focusing on the East Asian Summer Monsoon(EASM),is presented based on long-term simulations with fixed external forcing.The results suggest that after nearly 240 years of integration,SYCIM2.0 achieves a quasi-equilibrium state,albeit with small trends in the net radiation flux at the top-of-atmosphere(TOA)and Earth’s surface,as well as with global mean near-surface temperatures.Compared to observational and reanalysis data,the model realistically simulates spatial patterns of sea surface temperature(SST)and precipitation centers to include their annual cycles,in addition to the lower-level wind fields in the EASM region.However,it exhibits a weakened and eastward-shifted Western Pacific Subtropical High(WPSH),resulting in an associated precipitation bias.SYCIM2.0 robustly captures the dominant mode of the EASM and its close relationship with the El Niño-Southern Oscillation(ENSO)but exhibits relatively poor performance in simulating the second leading mode and the associated air–sea interaction processes.Further comprehensive evaluations of SYCIM2.0 will be conducted in future studies.展开更多
The limited creep resistance of wrought Mg-Al alloys restricts their lightweight applications at intermediate temperatures due to the softening effect of discontinuous precipitation(DP)on the dislocation-controlled cr...The limited creep resistance of wrought Mg-Al alloys restricts their lightweight applications at intermediate temperatures due to the softening effect of discontinuous precipitation(DP)on the dislocation-controlled creep.Here,we developed a creep-resistant wrought Mg-Al alloy through microalloying of Y and Ca.The resulting alloy exhibited an order of magnitude enhancement in the creep resistance at 125℃/50±100 MPa.In contrast to the grain boundary instabilities by DP in the previously reported wrought Mg-Al alloys,we show that the addition of 0.21Y+0.15Ca wt%produces a(Zn+Ca)co-segregation at the grain boundaries as a result of their segregation energy and the activation energy of grain boundary migration,thereby stabilizing the grain boundaries.The(Zn+Ca)co-segregation inhibits the dynamic DP and promotes the formation of intragranular Al-enriched clusters,which favorthe formation of Al_(2)Y,Mg_(17)Al_(12)nano precipitates,thereby impeding intragranular dislocation motion during creep.Furthermore,the addition of 0.21Y+0.15Ca wt%facilitates the formation of a fine and uniform recrystallization structure in the microalloyed alloys compared to AZ80 due to the high activation energy of mobility for the(Zn+Ca)segregated grain boundary.Therefore,the microalloyed alloys exhibit good tensile properties with 380 MPa tensile strength and 18%elongation.Our constitutive analysis revealed that the(Y+Ca)microalloying decreased the creep stress exponent by 29%and increased the creep resistance in the medium to high-stress range.Microalloying provides a promising way to develop low-cost creep-resistant wrought Mg-Al alloys.展开更多
The serrated flow behavior,known as the Portevin-Le Chatelier(PLC)effect,is commonly observed during high-temperature deformation.In this study,we report a serrated flow behavior in FeCoCrNiMo0.2 high-entropy alloy(HE...The serrated flow behavior,known as the Portevin-Le Chatelier(PLC)effect,is commonly observed during high-temperature deformation.In this study,we report a serrated flow behavior in FeCoCrNiMo0.2 high-entropy alloy(HEA),which is mediated by nano-twinning and phase transformation at cryogenic temperatures.During uniaxial tensile deformation at 77 K,the alloy exhibited the formation of high-density deformation nano-twinning,cross-twinning,stacking faults(SFs)and Lomer-Cottrell locks(L-C locks).Additionally,the lower stacking fault energy(SFE)at low temperatures promotes the formation of the 9R phase.The high-density twin boundaries effectively hinder dislocation movement,leading to the instability of plastic deformation and promoting the serrated flow behavior.Furthermore,the rapid and unstable transformation of the 9R phase contributes to the pronounced serrated flow behavior.Nano-twinning,SFs,cross-twinning,L-C locks and 9R phase collectively induce a dynamic Hall-Petch effect,enhancing the strength-ductility synergy and strain-hardening ability of deformed alloy at 77 K.Our work provides valuable insights into the mechanism of tensile deformation at cryogenic temperatures in single-phase FCC HEA.展开更多
Shale gas production involves complex gas-water two-phase flow,with flow patterns in proppant-filled fractures playing a critical role in determining production efficiency.In this study,3D geometric models of 40/70 me...Shale gas production involves complex gas-water two-phase flow,with flow patterns in proppant-filled fractures playing a critical role in determining production efficiency.In this study,3D geometric models of 40/70 mesh ceramic particles and quartz sand proppant clusters were elaborated using computed tomography(CT)scanning.These models were used to develop a numerical simulation framework based on the lattice Boltzmann method(LBM),enabling the investigation of gas-water flow behavior within proppant-filled fractures under varying driving forces and surface tensions.Simulation results at a closure pressure of 15 MPa have revealed that ceramic particles exhibit a simpler and more porous internal structure than quartz sand of the same size.Under identical flow conditions,ceramic proppants demonstrate higher fluid replacement efficiency.Replacement efficiency increases with higher porosity,greater driving force,and lower surface tension.Furthermore,fluid displacement is strongly influenced by pore geometry:flow is faster in straighter and wider channels,with preferential movement through larger pores forming dominant flow paths.The replacement velocity exhibits a characteristic time evolution,initially rapid,then gradually decreasing,correlating positively with the development of these dominant channels.展开更多
To address the challenges of low accuracy and insufficient real-time performance in dynamic object detection for UAV surveillance,this paper proposes a novel tracking framework that integrates a lightweight improved Y...To address the challenges of low accuracy and insufficient real-time performance in dynamic object detection for UAV surveillance,this paper proposes a novel tracking framework that integrates a lightweight improved YOLOv5s model with adaptive motion compensation.A UAV-view dynamic feature enhancement strategy is innovatively introduced,and a lightweight detection network combining attention mechanisms and multi-scale fusion is constructed.The robustness of tracking under motion blur scenarios is also optimized.Experimental results demonstrate that the proposed method achieves a mAP@0.5 of 68.2%on the VisDrone dataset and reaches an inference speed of 32 FPS on the NVIDIA Jetson TX2 platform.This significantly improves the balance between accuracy and efficiency in complex scenes,offering reliable technical support for real-time applications such as emergency response.展开更多
High-resolution seeing through complex scattering media such as turbid water,biological tissues,and mist is a significant challenge because the strong scattering scrambles the light paths and forms the scattering wall...High-resolution seeing through complex scattering media such as turbid water,biological tissues,and mist is a significant challenge because the strong scattering scrambles the light paths and forms the scattering wall.We propose an active polarized iterative optimization approach for high-resolution imaging through complex scattering media.By acquiring a series of sub-polarized images,we can capture the diverse pattern-illuminated images with various high-frequency component information caused by the Brownian motion of complex scattering materials,which are processed using the common-mode rejection of polarization characteristics to extract target information from scattering medium information.Following that,our computational reconstruction technique employs an iterative optimization algorithm that commences with patternilluminated Fourier ptychography for reconstructing the high-resolution scene.It is extremely important that our approach for high-resolution imaging through complex scattering media is not limited by priori information and optical memory effect.The proposed approach is suitable for not only dynamic but also static scattering media,which may find applications in the biomedicine field,such as skin abnormalities,non-invasive blood flow,and superficial tumors.展开更多
Salmonella grows better under aerobic conditions as a facultative anaerobic foodborne pathogenic bacteria.The oxygen-scavenging activity of Lactococcus lactis in the intestinal tract is a promising strategy for preven...Salmonella grows better under aerobic conditions as a facultative anaerobic foodborne pathogenic bacteria.The oxygen-scavenging activity of Lactococcus lactis in the intestinal tract is a promising strategy for preventing Salmonella infection.In this study,the aerobic respiration requirement and preventive mechanism of L.lactis subsp.lactis KLDS 4.0325 in murine models infected by Salmonella enterica subsp.enterica serovar Typhimurium(S.Typhimurium)SL1344 were investigated.Results indicate that L.lactis KLDS 4.0325 is capable of aerobic respiratory metabolism in the host intestine when exogenous heme exists,and decrease intestinal oxygen concentration,which in turn trigger autophagy of intestinal cells to reduce S.Typhimurium load,improve gut microbiota composition,alleviate intestinal barrier injury and inflammation response.These results suggest that aerobic respiration L.lactis KLDS 4.0325 can prevent S.Typhimurium infection in a new way in which by restoring intestinal cell hypoxia,maintaining immune balance and regulating intestinal flora.展开更多
Objective miR-34c-3p is down-regulated in nasopharyngeal carcinoma(NPC).The biological role of miR-34c-3p in NPC and its underlying mechanisms are unknown and were explored in this study.Methods Flow cytometry and imm...Objective miR-34c-3p is down-regulated in nasopharyngeal carcinoma(NPC).The biological role of miR-34c-3p in NPC and its underlying mechanisms are unknown and were explored in this study.Methods Flow cytometry and immunohistochemical staining were employed to detect cluster of differentiation 86(CD86)and cluster of differentiation 206(CD206)expression;quantitative real-time polymerase chain reaction(qRT-PCR)and western blotting were employed to examine mRNA expression and protein levels;cell counting kit-8(CCK8)and transwell assays were employed to assess cell proliferation,migration,and invasion;and hematoxylin-eosin(HE)staining was employed to assess pathological changes in tumor tissues.Results Our results revealed that the miR-34c-3p mimic markedly inhibited M2 polarization of macrophages by targeting SLC7A11,and M2 macrophages transfected with the miR-34c-3p mimic inhibited the proliferation,migration,and invasion of NPC cells.The in vivo experiments further confirmed that miR-34c-3p mimics blocked tumor growth and reduced inflammatory infiltration in tumor tissues.Conclusion This study provides novel insights into the pathogenesis of NPC and a new treatment strategy.展开更多
Accurate subseasonal forecasting of East Asian summer monsoon(EASM)precipitation is crucial,as it directly impacts the livelihoods of billions.However,the prediction skill of state-of-the-art subseasonal-to-seasonal(S...Accurate subseasonal forecasting of East Asian summer monsoon(EASM)precipitation is crucial,as it directly impacts the livelihoods of billions.However,the prediction skill of state-of-the-art subseasonal-to-seasonal(S2S)models for precipitation remains limited.In this study,the authors developed a convolutional neural network(CNN)regression model to enhance the prediction skill for weekly EASM precipitation by utilizing the more reliably predicted circulation fields from dynamic models.The outcomes of the CNN model are promising,as it led to a 14%increase in the anomaly correlation coefficient(ACC),from 0.30 to 0.35,and a 22%reduction in the root-mean-square error(RMSE),from 3.22 to 2.52,for predicting the weekly EASM precipitation index at a leading time of one week.Among the S2S models,the improvement in prediction skill through CNN correction depends on the model’s performance in accurately predicting circulation fields.The CNN correction of EASM precipitation index can only rectify the systematic errors of the model and is independent of whether the each grid point or the entire area-averaged index is corrected.Furthermore,u200(200-hPa zonal wind)is identified as the most important variable for efficient correction.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.92160301,92060203,52175415 and 52205475)the Science Center for Gas Turbine Project(Nos.P2022-AB-Ⅳ-002-001 and P2023-B-Ⅳ-003-001)+3 种基金the Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology(No.JSKL2223K01)the Natural Science Foundation of Jiangsu Province(No.BK20210295)the Superior Postdoctoral Project of Jiangsu Province(No.2022ZB215)the Henan Science and Technology Public Relations Project(No.212102210445).
文摘The undeformed chip thickness and grinding force are key parameters for revealing the material removal mechanism in the grinding process.However,they are difficult to be well expressed due to the ununiformed protrusion height and random position distribution of abrasive grains on the abrasive wheel surface.This study investigated the distribution of undeformed chip thickness and grinding force considering the non-uniform characteristics of abrasive wheel in the grinding of K4002 nickel-based superalloy.First,a novel grinding force model was established through a kinematic-geometric analysis and a grain-workpiece contact analysis.Then,a series of grinding experiments were conducted for verifying the model.The results indicate that the distribution of undeformed chip thickness is highly consistent with the Gaussian distribution formula.The increase in the grinding depth mainly leads to an increase in the average value of Gaussian distribution.On the contrary,the increase in the workpiece infeed speed or the decrease in the grinding speed mainly increases the standard deviation of Gaussian distribution.The average and maximum errors of the grinding force model are 4.9%and 14.6%respectively,indicating that the model is of high predication accuracy.
基金supported by the National Natural Science Foundation of China(32172059)Fundamental Research Funds for the Central Universities(SWUXDJH202315).
文摘Pre-harvest sprouting(PHS)describes the germination of physiologically mature grains in spikes prior to harvest in cereal crops.PHS could seriously decrease grain yield and quality,which makes it a major constraint to cereal production worldwide.A number of PHS-associated genes in cereals have been reported;however,the molecular mechanisms underlying PHS remain largely elusive.Here,we report a CRISPRCas9 mutant with severe PHS in a paddy field.The mutated gene OsMFT2 encodes a phosphatidylethanolamine-binding protein(PEBP).Intriguingly,the OsMFT1,in the same PEBP family,had the opposite effect in controlling rice PHS as does OsMFT2.Germination tests of seeds of chimeric protein-expressing plants revealed that the fourth exon conferred the antagonistic activity of OsMFT1 and OsMFT2 in rice PHS.Additionally,two lines of these plants showed elevated grain numbers per panicle,implying that chimeric protein has potential to significantly increase yield.Moreover,transcriptome analysis and genetic studies indicated that OsMFT1 and OsMFT2 performed opposing functions in rice PHS owing to three co-regulated genes that being contrastingly affected by OsMFT1 and OsMFT2.Overall,it seemed that the proper combination of PEBP family members could obtain optimal PHS resistance and high yield.
基金supported by the National Natural Science Foundation of China(61774140).
文摘ZnO thin films with varying Ta concentrations were fabricated through magnetron sputtering.The crystallinity and surface morphology of the ZnO films are significantly influenced by the incorporation of Ta,as evidenced by the X-ray diffraction and scanning electron microscopy results.The lattice constants,as determined by X-ray diffraction,contradict the disparity in Ta and Zn ion radii,which is attributed to the impact of interstitial defects.This inconsistency introduces variations in carrier concentration in this experiment compared with prior studies.Subsequent exploration of the luminescent characteristics and emission mechanism of defect levels in Ta-doped ZnO films was conducted through photoluminescence.Furthermore,the factors influencing the bandgap are discussed.
基金supported by the projects of the China Geological Survey(DD20230543,DD20221770).
文摘Fluorine(F)-enriched soils,resulting from geogenic processes or superimposed by anthropogenic activities,have raised significant concerns due to their phytotoxicity and potential threats to human health.Soils in central Guizhou Province exhibit F enrichment,with a mean F concentration of 1067 mg/kg.However,the associated human health risks and geochemical mechanisms driving F enrichment in these soils remain insufficiently understood.In areas with a natural geological background,the average concentrations of F in rice,vegetables,drinking water,and ambient air are 1.54 mg/kg,0.54 mg/kg,0.16 mg/L,and 0.29μg/m^(3),respectively.In contrast,samples collected near phosphorous chemical plants demonstrate elevated F concentrations:1.78 mg/kg in rice,1.53 mg/kg in vegetables,0.20 mg/L in drinking water,and 11.98μg/m^(3) in ambient air.Fluorine in soils was immobilized by apatite and clay minerals,and hardly transferred into water and crops.The fixation of F-by Ca^(2+)in water and by Fe/Al hydroxides and clay minerals in bottom sediment further reduces F concentrations in water.As a result,hazard quotient(HQ)values below 1.0 indicate negligible fluorine-related health risk in geological background regions.However,ambient air near phosphorous chemical plant exhibited a 41.3-fold increase in F concentration compared to geological background regions.Fluorine-laden emissions can be directly inhaled or deposited on vegetable leaves and orally ingested into human bodies.Improvement of F-rich waste gas disposal and restricted leafy vegetable cultivation are effective measures to reduce F health risks in phosphorous chemical plant regions.
基金supported by the projects of the Geological Survey(DD20240501104,DD20230422).
文摘Xining,a river valley city in China’s arid region,serves as an important industrial hub with a fragile ecological environment.While groundwater heavy metal pollution in this area has drawn increasing concern,the sources and associated human health risks remain inadequately understood.This study analyzed 144 shallow groundwater samples from urban Xining for 14 heavy metals(Fe,Al,B,Mn,Ba,Zn,Pb,Cr^(6+),Ni,Cu,Co,Sb,Cd,and As)using the Nemerow comprehensive pollution index,correlation analysis,and the USEPA health risk assessment model.Results identified Fe,Al,B,Mn,Ba,Pb,Cd,and As as the primary pollutants,especially concentrated in river valley plains.These contaminants primarily originate from natural sedimentary conditions and human activities such as industrial and agricultural development.The pollution indices for Al,Pb,Mn,and Fe exceeded clean water thresholds,indicating serious contamination and the need for enhanced regulation.Health risk assessments revealed that children face greater exposure risks than adults,with arsenic and nickel being the main contributors to carcinogenic risk.Sensitivity analysis further showed that As,Fe,and Cd posed the greatest non-carcinogenic and carcinogenic risks,particularly in human-impacted areas such as the Nanchuan and Beichuan valleys and Ganhegou.These findings provide essential insights for groundwater safety management in plateau river valley cities and similar vulnerable regions.
基金supported by the National Natural Science Foundation of China(Grant No.U2342208)support from NSF/Climate Dynamics Award#2025057。
文摘Predicting monsoon climate is one of the major endeavors in climate science and is becoming increasingly challenging due to global warming. The accuracy of monsoon seasonal predictions significantly impacts the lives of billions who depend on or are affected by monsoons, as it is essential for the water cycle, food security, ecology, disaster prevention, and the economy of monsoon regions. Given the extensive literature on Asian monsoon climate prediction, we limit our focus to reviewing the seasonal prediction and predictability of the Asian Summer Monsoon (ASM). However, much of this review is also relevant to monsoon predictions in other seasons and regions. Over the past two decades, considerable progress has been made in the seasonal forecasting of the ASM, driven by an enhanced understanding of the sources of predictability and the dynamics of seasonal variability, along with advanced development in sophisticated models and technologies. This review centers on advances in understanding the physical foundation for monsoon climate prediction (section 2), significant findings and insights into the primary and regional sources of predictability arising from feedback processes among various climate components (sections 3 and 4), the effects of global warming and external forcings on predictability (section 5), developments in seasonal prediction models and techniques (section 6), the challenges and limitations of monsoon climate prediction (section 7), and emerging research trends with suggestions for future directions (section 8). We hope this review will stimulate creative activities to enhance monsoon climate prediction.
基金supported by the National Natural Science Foundation of China(Nos.42072184 and 41702157)the Science and Technology Cooperation Project of the CNPC-SWPU Innovation Alliance。
文摘For an improved understanding of gas enrichment mechanism in the eastern Sichuan Basin,South China,twelve natural gas samples were obtained from carbonate reservoirs of the Upper Permian strata to analyze the hydrocarbon and non-hydrocarbon gas compositions,stable carbon and hydrogen isotopes ratios of hydrocarbons,and noble gas isotope ratios.The gas samples in the Upper Permian reservoirs principally consist of alkane gas with a dryness ratio ranging from 127.9 to 1564.4.The carbon isotope ratio of methane(δ^(13)C_(1))was almost constant at-34.1 to-31.3‰,but the carbon isotope ratio of ethane(δ^(13)C2)varied from-36.6‰to-25.8‰.The hydrogen isotope ratio of methane(δ^2HC_(1))also displayed a wide range from-137‰to-127‰.The large variations in the dryness ratio,δ^(13)C_(2),andδ^2HC_(1)with almost constantδ^(13)C_(1)suggest the mixing of sapropelic and humic origins for hydrocarbon gases in these reservoirs.A high concentration of hydrogen sulfide(H_(2)S)originated from the thermochemical sulfate reduction(TSR),which was positively correlated withδ^(13)C_(1)(orδ^(13)C_(2))in individual gas fields.TSR alteredδ^(13)C_(1)(orδ^(13)C_(2))and resulted in the abnormal character of isotopic reversal in the individual samples.Theδ^(13)C_(1)(orδ^(13)C_(2))in most gas samples,independent of H_(2)S concentration,further displayed reversed carbon isotopes because of the mixture of thermogenic gases with various thermal maturity levels.The measured argon isotope ratio(^(40)Ar/^(36)Ar)varied from 310 to 1225,which suggests that the oldest 320 Ma source rock age corresponds to Permian shales.The analysis of the gas origin and the identification of primary source rock have made a significant contribution to further understanding the resource potential and distribution of natural gas in the Upper Permian,and have great implications for gas exploration in the eastern Sichuan Basin.
基金Supported by the Health Commission of Guangxi Zhuang Autonomous Region Self-Funded Research Projects,No.Z20180575 and No.Z-A20231058.
文摘BACKGROUND Postoperative delirium(POD)is a concerning complication of organ transplantation.With organ transplantation offering hope to patients with end-stage organ disease,understanding the incidence and risk factors of POD is crucial,as it can significantly affect patients’prognosis and healthcare costs.AIM To systematically evaluate the incidence and risk factors of POD following organ transplantation to facilitate clinical prevention and optimize patient management and prognosis.METHODS Multiple databases such as PubMed and their reference lists were comprehensively searched using a combination of keywords related to organ transplantation and POD.Relevant observational studies on patients who had undergone solid organ transplantation and randomized controlled trials containing relevant analyses were included.Duplicated,data-deficient,non-English,and non-original data studies were excluded.Data were extracted independently by two researchers and then cross-checked.The Newcastle-Ottawa scale was used to evaluate the quality of the included studies.RevMan 5.3 was employed for data analysis.The pooled incidence of POD was calculated according to the data type,and the fixed or random effect model was employed to analyze risk factors based on heterogeneity.Subsequently,sensitivity analysis and publication bias assessments were performed.RESULTS A total of 39 relevant literatures were included.The overall incidence of POD in the organ transplant group was 20%[95%confidence interval(CI):18%-22%];liver transplant group,22%(95%CI:17%-26%);lung transplant group,34%(95%CI:23%-45%);and kidney transplant group,6%(95%CI:2%-10%).Primary graft dysfunction increased the POD risk,with a pooled odds ratio(OR)(95%CI)of 1.78(1.09-2.91).A history of hepatic encephalopathy increased the POD risk,with a pooled OR(95%CI)of 3.19(2.30-4.43).The higher the Acute Physiology and Chronic Health Evaluation II score,the greater the POD risk,with a pooled OR(95%CI)of 1.52(1.09-2.12).A history of alcohol abuse increased the POD risk,with a pooled OR(95%CI)of 2.84(1.74-4.65).Thus,the higher the model for end-stage liver disease score,the greater the POD risk,with a pooled OR(95%CI)of 2.49(1.14-5.43).POD was more likely to develop in patients with preoperative infections,with a pooled OR(95%CI)of 2.78(1.56-4.97).The use of diuretics increased the POD risk,with a pooled OR(95%CI)of 2.36(1.38-4.04).CONCLUSION In this study,the overall incidence of POD in patients who underwent organ transplantation is 20%.The incidence varies among different types of organ transplantation,and multiple factors can increase the POD risk.
基金Supported by National Natural Science Foundation of China,No.81902805Jiangsu Provincial Natural Science Foundation,No.BK20190174+1 种基金Suzhou Gusu Health Talent Research Project,No.GSWS2023039Suzhou Medical Youth Talents Project,No.Qngg2024004.
文摘BACKGROUND Gastric cancer(GC)is among the most common malignant tumors and remains a leading cause of cancer-related mortality worldwide.Furthermore,exosomal miRNAs are regarded as promising noninvasive biomarkers for diagnosing malignant tumors.AIM To investigate the expression of exosomal miR-17-92 clusters and develop a potential biomarker for GC diagnosis METHODS Exosomes were isolated from serum samples obtained from 72 GC patients and 20 healthy controls.The isolated exosomes were validated using transmission electron microscopy,nanoparticle tracking analysis,and western blotting.Exosomal RNA was then extracted,and the expression profile of the miR-17-92 cluster was analyzed using qRT-PCR.Statistical methods were employed to evaluate the relationship between the serum exosomal miR-17-92 cluster expre-ssion and the clinicopathological parameters of GC patients as well as to assess the diagnostic utility of these miRNAs.RESULTS The expression of four members of the exosomal miR-17-92 cluster-miR-17,miR-18,miR-19a,and miR-92-was significantly upregulated in the serum samples of patients with GC compared with those of healthy controls.The miR-17-92 cluster panel demonstrated substantially higher clinical diagnostic value for GC than any individual component or pair.Additionally,the expression of traditional tumor biomarkers-carcinoembryonic antigen and carbohydrate antigen 19-9-was significantly elevated in the serum of patients with GC compared with that of healthy controls.Each biomarker,whether alone or in combination,effectively differentiated the patients from healthy controls.Furthermore,a combined panel of the two traditional tumor biomarkers and the four miR-17-92 cluster members exhibited the highest diagnostic accuracy for GC.Elevated miR-17-92 expression was also strongly associated with tumor size,tumor depth,lymph node metastasis,distant metastasis,and tumor-node-metastasis stage.CONCLUSION Our findings revealed that the circulating exosomal miR-17-92 cluster may be used as a potential noninvasive biomarker to improve diagnostic efficiency for GC.
基金support from the National Natural Science Foundation of China(Grant Nos.52301137,51974097,52364050)the Natural Science Special Foundation of Guizhou University(No.(2023)20)+1 种基金Guizhou Province Science and Technology Project(Grant Nos.[2023]001,[2019]2163)Guiyang city Science and Technology Project(Grant No.[2023]48-16).
文摘The dynamic mechanical response and deformation mechanism of magnesium-yttrium alloy at high strain rate were investigated using split-Hopkinson pressure bar(SHPB)impact,and the microstructure evolution and crack formation mechanism were revealed.The yield strength and work hardening rate increase significantly with increasing impact strain rate.Deformation twinning and non-basal dislocation slip are the primary deformation mechanisms during testing.Contrary to crack initiation mechanism facilitated by adiabatic shear bands,we find that high-density co-axial nanocrystalline grains form near cracks,which leads to local softening and promotes crack initiation and rapid propagation.Most grains have similar<1^(-)21^(-)0>orientations,with unique misorientation of 24°,32°,62°,78°and 90°between adjacent grains,suggesting that these grains are primarily formed by interface transformation,which exhibits distinct differences from recrystallized grains.Our results shed light upon the dynamic mechanical response and crack formation mechanism in magnesium alloys under impact deformation.
基金funded by the National Natural Science Foundation of China(Grant Nos.U21A6001,42261144687,42175173)the Project supported by Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(Grant No.SML2023SP208)the GuangDong Basic and Applied Basic Research Foundation(2023A1515240036).
文摘Based on the C-Coupler platform,the semi-unstructured Climate System Model,Synthesis Community Integrated Model version 2(SYCIM2.0),has been developed at the School of Atmospheric Sciences,Sun Yat-sen University.SYCIM2.0 aims to meet the demand for seamless climate prediction through accurate climate simulations and projections.This paper provides an overview of SYCIM2.0 and highlights its key features,especially the coupling of an unstructured ocean model and the tuning process.An extensive evaluation of its performance,focusing on the East Asian Summer Monsoon(EASM),is presented based on long-term simulations with fixed external forcing.The results suggest that after nearly 240 years of integration,SYCIM2.0 achieves a quasi-equilibrium state,albeit with small trends in the net radiation flux at the top-of-atmosphere(TOA)and Earth’s surface,as well as with global mean near-surface temperatures.Compared to observational and reanalysis data,the model realistically simulates spatial patterns of sea surface temperature(SST)and precipitation centers to include their annual cycles,in addition to the lower-level wind fields in the EASM region.However,it exhibits a weakened and eastward-shifted Western Pacific Subtropical High(WPSH),resulting in an associated precipitation bias.SYCIM2.0 robustly captures the dominant mode of the EASM and its close relationship with the El Niño-Southern Oscillation(ENSO)but exhibits relatively poor performance in simulating the second leading mode and the associated air–sea interaction processes.Further comprehensive evaluations of SYCIM2.0 will be conducted in future studies.
基金financial support from the National Natural Science Foundation of China(No:52061040,No:52371121,No:52031011)China Postdoctoral Science Foundation(No:2021M692512)the 2020 open projects(No:KLATM202003)of Key Laboratory of Advanced Technologies of Materials,Ministry of Education China,Southwest Jiaotong University。
文摘The limited creep resistance of wrought Mg-Al alloys restricts their lightweight applications at intermediate temperatures due to the softening effect of discontinuous precipitation(DP)on the dislocation-controlled creep.Here,we developed a creep-resistant wrought Mg-Al alloy through microalloying of Y and Ca.The resulting alloy exhibited an order of magnitude enhancement in the creep resistance at 125℃/50±100 MPa.In contrast to the grain boundary instabilities by DP in the previously reported wrought Mg-Al alloys,we show that the addition of 0.21Y+0.15Ca wt%produces a(Zn+Ca)co-segregation at the grain boundaries as a result of their segregation energy and the activation energy of grain boundary migration,thereby stabilizing the grain boundaries.The(Zn+Ca)co-segregation inhibits the dynamic DP and promotes the formation of intragranular Al-enriched clusters,which favorthe formation of Al_(2)Y,Mg_(17)Al_(12)nano precipitates,thereby impeding intragranular dislocation motion during creep.Furthermore,the addition of 0.21Y+0.15Ca wt%facilitates the formation of a fine and uniform recrystallization structure in the microalloyed alloys compared to AZ80 due to the high activation energy of mobility for the(Zn+Ca)segregated grain boundary.Therefore,the microalloyed alloys exhibit good tensile properties with 380 MPa tensile strength and 18%elongation.Our constitutive analysis revealed that the(Y+Ca)microalloying decreased the creep stress exponent by 29%and increased the creep resistance in the medium to high-stress range.Microalloying provides a promising way to develop low-cost creep-resistant wrought Mg-Al alloys.
基金supported by the National Natural Science Foundation of China(Nos.52474403,52364050 and 52301137)Guizhou Provincial Program on Commercialization of Scientific and Technological Achievements(No.[2023]001)+2 种基金Guizhou Province Science and Technology Project(No.[2022]050)Guiyang city Science and Technology Project(No.[2023]48-16)the Central Government in Guidance of Local Science and Technology Development Funds(No.[2024]032).
文摘The serrated flow behavior,known as the Portevin-Le Chatelier(PLC)effect,is commonly observed during high-temperature deformation.In this study,we report a serrated flow behavior in FeCoCrNiMo0.2 high-entropy alloy(HEA),which is mediated by nano-twinning and phase transformation at cryogenic temperatures.During uniaxial tensile deformation at 77 K,the alloy exhibited the formation of high-density deformation nano-twinning,cross-twinning,stacking faults(SFs)and Lomer-Cottrell locks(L-C locks).Additionally,the lower stacking fault energy(SFE)at low temperatures promotes the formation of the 9R phase.The high-density twin boundaries effectively hinder dislocation movement,leading to the instability of plastic deformation and promoting the serrated flow behavior.Furthermore,the rapid and unstable transformation of the 9R phase contributes to the pronounced serrated flow behavior.Nano-twinning,SFs,cross-twinning,L-C locks and 9R phase collectively induce a dynamic Hall-Petch effect,enhancing the strength-ductility synergy and strain-hardening ability of deformed alloy at 77 K.Our work provides valuable insights into the mechanism of tensile deformation at cryogenic temperatures in single-phase FCC HEA.
文摘Shale gas production involves complex gas-water two-phase flow,with flow patterns in proppant-filled fractures playing a critical role in determining production efficiency.In this study,3D geometric models of 40/70 mesh ceramic particles and quartz sand proppant clusters were elaborated using computed tomography(CT)scanning.These models were used to develop a numerical simulation framework based on the lattice Boltzmann method(LBM),enabling the investigation of gas-water flow behavior within proppant-filled fractures under varying driving forces and surface tensions.Simulation results at a closure pressure of 15 MPa have revealed that ceramic particles exhibit a simpler and more porous internal structure than quartz sand of the same size.Under identical flow conditions,ceramic proppants demonstrate higher fluid replacement efficiency.Replacement efficiency increases with higher porosity,greater driving force,and lower surface tension.Furthermore,fluid displacement is strongly influenced by pore geometry:flow is faster in straighter and wider channels,with preferential movement through larger pores forming dominant flow paths.The replacement velocity exhibits a characteristic time evolution,initially rapid,then gradually decreasing,correlating positively with the development of these dominant channels.
文摘To address the challenges of low accuracy and insufficient real-time performance in dynamic object detection for UAV surveillance,this paper proposes a novel tracking framework that integrates a lightweight improved YOLOv5s model with adaptive motion compensation.A UAV-view dynamic feature enhancement strategy is innovatively introduced,and a lightweight detection network combining attention mechanisms and multi-scale fusion is constructed.The robustness of tracking under motion blur scenarios is also optimized.Experimental results demonstrate that the proposed method achieves a mAP@0.5 of 68.2%on the VisDrone dataset and reaches an inference speed of 32 FPS on the NVIDIA Jetson TX2 platform.This significantly improves the balance between accuracy and efficiency in complex scenes,offering reliable technical support for real-time applications such as emergency response.
基金supported by the National Natural Science Foundation of China(Grant Nos.62205259,62075175,62105254,and 62375212)the National Key Laboratory of Infrared Detection Technologies(Grant No.IRDT-23-06)+1 种基金the Fundamental Research Funds for the Central Universities(Grant Nos.XJSJ24028,XJS222202,ZYTS24097,and ZYTS24095)the Open Research Fund of Beijing Key Laboratory of Advanced Optical Remote Sensing Technology.
文摘High-resolution seeing through complex scattering media such as turbid water,biological tissues,and mist is a significant challenge because the strong scattering scrambles the light paths and forms the scattering wall.We propose an active polarized iterative optimization approach for high-resolution imaging through complex scattering media.By acquiring a series of sub-polarized images,we can capture the diverse pattern-illuminated images with various high-frequency component information caused by the Brownian motion of complex scattering materials,which are processed using the common-mode rejection of polarization characteristics to extract target information from scattering medium information.Following that,our computational reconstruction technique employs an iterative optimization algorithm that commences with patternilluminated Fourier ptychography for reconstructing the high-resolution scene.It is extremely important that our approach for high-resolution imaging through complex scattering media is not limited by priori information and optical memory effect.The proposed approach is suitable for not only dynamic but also static scattering media,which may find applications in the biomedicine field,such as skin abnormalities,non-invasive blood flow,and superficial tumors.
基金supported by the National Natural Science Foundation of China(32072190 and 32101929)Academic Backbone Plan of Northeast Agricultural University(20XG12)。
文摘Salmonella grows better under aerobic conditions as a facultative anaerobic foodborne pathogenic bacteria.The oxygen-scavenging activity of Lactococcus lactis in the intestinal tract is a promising strategy for preventing Salmonella infection.In this study,the aerobic respiration requirement and preventive mechanism of L.lactis subsp.lactis KLDS 4.0325 in murine models infected by Salmonella enterica subsp.enterica serovar Typhimurium(S.Typhimurium)SL1344 were investigated.Results indicate that L.lactis KLDS 4.0325 is capable of aerobic respiratory metabolism in the host intestine when exogenous heme exists,and decrease intestinal oxygen concentration,which in turn trigger autophagy of intestinal cells to reduce S.Typhimurium load,improve gut microbiota composition,alleviate intestinal barrier injury and inflammation response.These results suggest that aerobic respiration L.lactis KLDS 4.0325 can prevent S.Typhimurium infection in a new way in which by restoring intestinal cell hypoxia,maintaining immune balance and regulating intestinal flora.
文摘Objective miR-34c-3p is down-regulated in nasopharyngeal carcinoma(NPC).The biological role of miR-34c-3p in NPC and its underlying mechanisms are unknown and were explored in this study.Methods Flow cytometry and immunohistochemical staining were employed to detect cluster of differentiation 86(CD86)and cluster of differentiation 206(CD206)expression;quantitative real-time polymerase chain reaction(qRT-PCR)and western blotting were employed to examine mRNA expression and protein levels;cell counting kit-8(CCK8)and transwell assays were employed to assess cell proliferation,migration,and invasion;and hematoxylin-eosin(HE)staining was employed to assess pathological changes in tumor tissues.Results Our results revealed that the miR-34c-3p mimic markedly inhibited M2 polarization of macrophages by targeting SLC7A11,and M2 macrophages transfected with the miR-34c-3p mimic inhibited the proliferation,migration,and invasion of NPC cells.The in vivo experiments further confirmed that miR-34c-3p mimics blocked tumor growth and reduced inflammatory infiltration in tumor tissues.Conclusion This study provides novel insights into the pathogenesis of NPC and a new treatment strategy.
基金supported by a Guangdong Major Project of Basic and Applied Basic Research[grant number 2020B0301030004]the National Natural Science Foundation of China[grant number 42175061]。
文摘Accurate subseasonal forecasting of East Asian summer monsoon(EASM)precipitation is crucial,as it directly impacts the livelihoods of billions.However,the prediction skill of state-of-the-art subseasonal-to-seasonal(S2S)models for precipitation remains limited.In this study,the authors developed a convolutional neural network(CNN)regression model to enhance the prediction skill for weekly EASM precipitation by utilizing the more reliably predicted circulation fields from dynamic models.The outcomes of the CNN model are promising,as it led to a 14%increase in the anomaly correlation coefficient(ACC),from 0.30 to 0.35,and a 22%reduction in the root-mean-square error(RMSE),from 3.22 to 2.52,for predicting the weekly EASM precipitation index at a leading time of one week.Among the S2S models,the improvement in prediction skill through CNN correction depends on the model’s performance in accurately predicting circulation fields.The CNN correction of EASM precipitation index can only rectify the systematic errors of the model and is independent of whether the each grid point or the entire area-averaged index is corrected.Furthermore,u200(200-hPa zonal wind)is identified as the most important variable for efficient correction.
