Machine-learning and big data are among the latest approaches in corrosion research.The biggest challenge in corrosion research is to accurately predict how materials will degrade in a given environment.Corrosion big ...Machine-learning and big data are among the latest approaches in corrosion research.The biggest challenge in corrosion research is to accurately predict how materials will degrade in a given environment.Corrosion big data is the application of mathematical methods to huge amounts of data to find correlations and infer probabilities.It is possible to use corrosion big data method to distinguish the influence of the minimal changes of alloying elements and small differences in microstructure on corrosion resistance of low alloy steels.In this research,corrosion big data evaluation methods and machine learning were used to study the effect of Sb and Sn,as well as environmental factors on the corrosion behavior of low alloy steels.Results depict corrosion big data method can accurately identify the influence of various factors on corrosion resistance of low alloy and is an effective and promising way in corrosion research.展开更多
Acute myocardial infarction(AMI)is a severe cardiovascular disease.This study aimed to identify crucial microRNAs(miRNAs)and mRNAs in AMI by establishing a miRNA-mRNA network.The microarray datasets GSE31568,GSE148153...Acute myocardial infarction(AMI)is a severe cardiovascular disease.This study aimed to identify crucial microRNAs(miRNAs)and mRNAs in AMI by establishing a miRNA-mRNA network.The microarray datasets GSE31568,GSE148153,and GSE66360 were downloaded from the Gene Expression Omnibus(GEO)database.We identified differentially expressed miRNAs(DE-miRNAs)and mRNAs(DE-mRNAs)in AMI samples compared with normal control samples.The consistently changing miRNAs in both GSE31568 and GSE148153 datasets were selected as candidate DE-miRNAs.The interactions between the candidate DE-miRNAs and DE-mRNAs were analyzed,and a miRNA-mRNA network and a protein-protein interaction network were constructed,along with functional enrichment and pathway analyses.A total of 209 DE-miRNAs in the GSE31568 dataset,857 DE-miRNAs in the GSE148153 dataset,and 351 DE-mRNAs in the GSE66360 dataset were identified.Eighteen candidate DE-miRNAs were selected from both the GSE31568 and GSE148153 datasets.Furthermore,miR-646,miR-127-5p,miR-509-5p,miR-509-3-5p,and miR-767-5p were shown to have a higher degree in the miRNA-mRNA network.THBS-1 as well as FOS was a hub gene in the miRNA-mRNA network and the protein-protein interaction(PPI)network,respectively.CDKN1A was important in both miRNA-mRNA network and PPI network.We established a miRNA-mRNA network in AMI and identified five miRNAs and three genes,which might be used as biomarkers and potential therapeutic targets for patients with AMI.展开更多
Dielectric barrier discharge(DBD) is utilized to decompose xylene vapor in mobile gas under normal atmospheric pressure.The plasma is generated by an AC power source with a frequency of 6 kHz.In the experiment,the d...Dielectric barrier discharge(DBD) is utilized to decompose xylene vapor in mobile gas under normal atmospheric pressure.The plasma is generated by an AC power source with a frequency of 6 kHz.In the experiment,the discharge power on the DBD reactor was calculated by a Lissajous figure,and the specific input energy(SIE) of different discharge voltage or residence time was obtained.The concentrations of xylene,carbon monoxide and carbon dioxide in the gas were analyzed by gas chromatography.The spectra of DBD were diagnosed using a spectrometer.We calculated the conversion rate(CR),mineralization rate(MR) and carbon dioxide selectivity.The relationship between these quantities and the SIE was analyzed.The experimental results show that high concentration xylene can be decomposed mostly by DBD plasma.The CR can reach as high as 90%with the main product of carbon dioxide.展开更多
The quantitative realtime polymerase chain reaction(RT-qPCR)is a powerful and sensitive method to measure expression of targeted gene but it highly relies on the use of suitable reference genes for data normalization....The quantitative realtime polymerase chain reaction(RT-qPCR)is a powerful and sensitive method to measure expression of targeted gene but it highly relies on the use of suitable reference genes for data normalization.We evaluated the expressions of 8 housekeeping genes:18S ribosomal rDNA(18S rDNA),28S ribosomal r DNA(28S rDNA),rubisco large subunit(rbc-L),β-actin(ACT),glyceraldehyde-3-phosphate dehydrogenase(GAPDH),elongation factor 1(EF1),β-tubulin(Tub B),and P-phycoerythrin B(PEB),to select the suitable reference genes for different life-history stages(tetrasporophyte,carposporophyte,and male/female gametophyte)of Gracilaria vermiculophylla by absolute quantitative method.Softwares geNorm and BestKeeper were used to verify the results acquired from copy number analysis.Results show that the expression of identified reference genes varied in comparing groups composed of different type of life stages.It is suggested that 18S rDNA and TubB could be used for highly complex samples composed of mixed ploidy and phases.18S rDNA and 28S rDNA were also preferred for using among the matured isomorphic samples.But for samples with different maturities,TubB and ACT were recommended for tetrasporophytes and gametophytes respectively.展开更多
The particle collision behavior and heat transfer performance are investigated to reveal the heat transfer enhancement and fouling prevention mechanism in a Na_(2)SO_(4) circulating fluidized bed evaporator.The partic...The particle collision behavior and heat transfer performance are investigated to reveal the heat transfer enhancement and fouling prevention mechanism in a Na_(2)SO_(4) circulating fluidized bed evaporator.The particle collision signals are analyzed with standard deviation by varying the amount of added particles ε(1%–3%),circulation flow velocity u(0.37–1.78 m·s^(-1)),and heat flux q(7.29–12.14 kW·m^(-2)).The results show that the enhancement factor reach up to 14.6%by adding polytetrafluoroethylene particles at ε=3%,u=1.78 m·s^(-1),and q=7.29 kW·m^(-2).Both the standard deviation of the particle collision signal and enhancement factor increase with the increase in the amount of added particles.The standard deviation increases with the increase in circulation flow velocity;however,the enhancement factor initially decreases and then increases.The standard deviation slightly decreases with the increase in heat flux at low circulation flow velocity,but initially increases and then decreases at high circulation flow velocity.The enhancement factor decreases with the increase in heat flux.The enhancement factor in Na_(2)SO_(4) solution is superior to that in water at high amount of added particles.The empirical correlation for heat transfer is established,and the model results agree well with the experimental data.展开更多
The superior vena cava(SVC)is the main component of non-pulmonary vein(PV)ectopy in patients with atrial fibrillation(AF).Researchers have found that epicardial adipose tissue(EAT)volume is related to the AF substrate...The superior vena cava(SVC)is the main component of non-pulmonary vein(PV)ectopy in patients with atrial fibrillation(AF).Researchers have found that epicardial adipose tissue(EAT)volume is related to the AF substrate,which can be defined by the low voltage area(LVA).This study aimed to investigate the relationship between SVC-EAT and SVC-AF.Twenty-six patients with SVC-AF triggers were identified as the SVC-AF group.Other three groups were defined and included as the LVA-AF group(LVA>5%),non-LVA-AF group(LVA<5%),and physical examination(PE)group.EAT around left atrium(LA-EAT)and SVC-EAT volumes were obtained using a cardiac risk assessment module.According to the SVC/LA-EAT ratio,there are significant differences between the SVC-AF group and the three control groups(the SVC-AF group 0.092±0.041 vs.the LVA-AF group 0.054±0.026,the non-LVA-AF group 0.052±0.022,and the PE group 0.052±0.019,all P<0.001).Receiver operating characteristic curve analysis suggests the optimal cut-off point of SVC/LA-EAT ratio is 6.8%for detecting SVC-AF patients,with 81.1%sensitivity,73.1%specificity,and an area under the curve of 0.83(95%confidence interval,0.75-0.91).Those with SVC-AF have a higher SVC/LA-EAT ratio and empirical SVC isolation could be considered if the SVC/LA-EAT ratio was over 6.8%.展开更多
In order to analyze the microscopic theory of viscous-elastic fluid flooding residual oil, the flow equation of polymer solution in the micro pore can be derived by selecting upper-convected Maxwell constitutive equat...In order to analyze the microscopic theory of viscous-elastic fluid flooding residual oil, the flow equation of polymer solution in the micro pore can be derived by selecting upper-convected Maxwell constitutive equation, continuity equation and motion equation. Then, the flow velocity field and stress field can be calculated under the boundary condition, and with the theory of stress tensor, the horizontal stress difference of polymer solution acting on the residual oil can be calculated. The results show that the greater the elasticity of viscous-elastic fluid is, the wider the flow channel is, the greater the horizontal stress difference is. The force acting on residual oil by viscous-elastic fluid can be increased by increasing the concentration of the polymer solution.展开更多
To take full advantage of the natural hazel resources and improve its yield and quality in Great Xing’an Ridge region, we carried out an initial investigation. The result showed that: there are two species in this ar...To take full advantage of the natural hazel resources and improve its yield and quality in Great Xing’an Ridge region, we carried out an initial investigation. The result showed that: there are two species in this area: Corylus heterophlla and Corylus mandshurica. They mainly distribute from south of XinLin town, HuMa county, Heilongjiang province to south boundary of Great Xing’ an Ridge in mountain and hilly areas. Most of hazel in this area was under the state of natural growth with no scientific man-management. Soil where Corylus heterophlla grew was about 40 cm to 50 cm and Corylus mandshurica was 30 cm to 45 cm. The main plant disease was powdery mildew and insect pest were Curculio dieckmani, Zeuzera sp. and Faust Cockchafer. 100-seed weight of Corylus heterophylla was more than twice of Corylus mandshuria. However, Corylus mandshuria was plumper, had much more kernel and much less empty shell than Corylus heterophylla, and what’s more, shell sickness of it turned to be significantly thinner than Corylus heterophylla, all of which showed great cultivation value and economic commodity value.展开更多
Objective:To study the effective value of introducing the concept of early oral exercise in the process of nursing intervention for preterm infants in the neonatal intensive care unit(NICU).Methods:96 cases of preterm...Objective:To study the effective value of introducing the concept of early oral exercise in the process of nursing intervention for preterm infants in the neonatal intensive care unit(NICU).Methods:96 cases of preterm infants diagnosed from January 2022 to August 2022 were selected and randomly divided into two groups:the general practice group(general nursing intervention),and the early practice group(early oral exercise intervention),and the effect of intervention on preterm infants in the two groups was observed.Results:After nursing care,the mean value of the non-nutritive sucking ability assessment(76.54±5.82),the mean value of the intellectual development degree assessment(104.57±8.45),the mean value of the psychomotor development degree assessment(102.33±6.74),and the mean value of behavioral neural reflexes ability assessment(38.71±2.40)in the early practice group were better than that as compared to the general practice group(P<0.05);the mean value of oral feeding start time of preterm infants in the early practice group(35.42±7.63)weeks,the mean value of all oral feeding time(34.12±5.28)weeks,and the mean time of hospital intervention(15.33±4.25)days were lesser than compared to those of the general practice group at 37.4±5.82 weeks,37.46±3.55 weeks,and 20.46±2.91 days,respectively(P<0.05);the rate of adverse reactions in preterm infants in the early practice group significantly lower than that of the general practice group(P<0.05).Conclusion:The introduction of the concept of early oral exercise intervention among NICU nurses improved the feeding effect,sucking ability of preterm infants,and intellectual development.Hence,early oral motor care should be popularized.展开更多
The onset of retinal degenerative disease is often associated with neuronal loss. Therefore, how to regenerate new neurons to restore vision is an important issue. NeuroD1 is a neural transcription factor with the abi...The onset of retinal degenerative disease is often associated with neuronal loss. Therefore, how to regenerate new neurons to restore vision is an important issue. NeuroD1 is a neural transcription factor with the ability to reprogram brain astrocytes into neurons in vivo. Here, we demonstrate that in adult mice, NeuroD1 can reprogram Müller cells, the principal glial cell type in the retina, to become retinal neurons. Most strikingly, ectopic expression of NeuroD1 using two different viral vectors converted Müller cells into different cell types. Specifically, AAV7 m8 GFAP681::GFP-ND1 converted Müller cells into inner retinal neurons, including amacrine cells and ganglion cells. In contrast, AAV9 GFAP104::ND1-GFP converted Müller cells into outer retinal neurons such as photoreceptors and horizontal cells, with higher conversion efficiency. Furthermore, we demonstrate that Müller cell conversion induced by AAV9 GFAP104::ND1-GFP displayed clear dose-and time-dependence. These results indicate that Müller cells in adult mice are highly plastic and can be reprogrammed into various subtypes of retinal neurons.展开更多
Understanding cardiac blood flow behaviors is of importance for cardiovascular research and clinical assessment of ventricle functions.Patient-specific Echo-based left ventricle(LV)fluid-structure interaction(FSI)mode...Understanding cardiac blood flow behaviors is of importance for cardiovascular research and clinical assessment of ventricle functions.Patient-specific Echo-based left ventricle(LV)fluid-structure interaction(FSI)models were introduced to perform ventricle mechanical analysis,investigate flow behaviors,and evaluate the impact of myocardial infarction(MI)and hypertension on blood flow in the LV.Echo image data were acquired from 3 patients with consent obtained:one healthy volunteer(P1),one hypertension patient(P2),and one patient who had an inferior and posterior myocardial infarction(P3).The nonlinear Mooney-Rivlin model was used for ventricle tissue with material parameter values chosen to match echo-measure LV volume data.Using the healthy case as baseline,LV with MI had lower peak flow velocity(30%lower at beginejection)and hypertension LV had higher peak flow velocity(16%higher at begin-filling).The vortex area(defined as the area with vorticity>0)for P3 was 19%smaller than that of P1.The vortex area for P2 was 12%smaller than that of P1.At peak of filling,the maximum flow shear stress(FSS)for P2 and P3 were 390%higher and 63%lower than that of P1,respectively.Meanwhile,LV stress and strain of P2 were 41%and 15%higher than those of P1,respectively.LV stress and strain of P3 were 36%and 42%lower than those of P1,respectively.In conclusion,FSI models could provide both flow and structural stress/strain information which would serve as the base for further cardiovascular investigations related to disease initiation,progression,and treatment strategy selections.Large-scale studies are needed to validate our findings.展开更多
Starch is a major storage carbohydrate in plants and is critical in crop yield and quality.Starch synthesis is intricately regulated by internal metabolic processes and external environmental cues;however,the precise ...Starch is a major storage carbohydrate in plants and is critical in crop yield and quality.Starch synthesis is intricately regulated by internal metabolic processes and external environmental cues;however,the precise molecular mechanisms governing this process remain largely unknown.In this study,we revealed that high red to far-red(high R:FR)light significantly induces the synthesis of leaf starch and the expression of synthesis-related genes,whereas low R:FR light suppress these processes.Arabidopsis phytochrome B(phyB),the primary R and FR photoreceptor,was identified as a critical positive regulator in this process.Downstream of phyB,basic leucine zipper transcription factor ELONGATED HYPOCOTYL5(HY5)was found to enhance starch synthesis,whereas the basic helix-loop-helix transcription factors PHYTOCHROME INTERACTING FACTORs(PIF3,PIF4,and PIF5)inhibit starch synthesis in Arabidopsis leaves.Notably,HY5 and PIFs directly compete for binding to a shared G-box cis-element in the promoter region of genes encoding starch synthases GBSS,SS3,and SS4,which leads to antagonistic regulation of their expression and,consequently,starch synthesis.Our findings highlight the vital role of phyB in enhancing starch synthesis by stabilizing HY5 and facilitating PIFs degradation under high R:FR light conditions.Conversely,under low R:FR light,PIFs predominantly inhibit starch synthesis.This study provides insight into the physiological and molecular functions of phyB and its downstream transcription factors HY5 and PIFs in starch synthesis regulation,shedding light on the regulatory mechanism by which plants synchronize dynamic light signals with metabolic cues to module starch synthesis.展开更多
Current guidelines encourage large studies in a diverse population to establish normal reference ranges for three-dimensional(3D)echocardiography for different ethnic groups.This study was designed to establish the no...Current guidelines encourage large studies in a diverse population to establish normal reference ranges for three-dimensional(3D)echocardiography for different ethnic groups.This study was designed to establish the normal values of 3D-left ventricular(LV)and left atrial(LA)volume and function in a nationwide,population-based cohort of healthy Han Chinese adults.A total of 1117 healthy volunteers aged 18–89 years were enrolled from 28 collaborating laboratories in China.Two sets of 3D echocardiographic instruments were used,and full-volume echocardiographic images were recorded and transmitted to a core laboratory for image analysis with a vendor-independent off-line workstation.Finally,866 volunteers(mean age of 48.4 years,402 men)were qualified for final analysis.Most parameters exhibited substantial differences between different sex and age groups,even after indexation by body surface area.The normal ranges of 3D-LV and 3D-LA volume and function differed from those recommended by the American Society of Echocardiography and the European Association of Cardiovascular Imaging guidelines,presented by the World Alliance Societies of Echocardiography(WASE)study,and from the 2D values in the EMINCA study.The normal reference values of 3D echocardiography-derived LV and LA volume and function were established for the first time in healthy Han Chinese adults.Normal ranges of 3D-LV and 3D-LA echocardiographic measurements stratified with sex,age,and race should be recommended for clinical applications.展开更多
After approaching 0℃owing to an Atlantic storm at the end of 2015,the Arctic temperature approached freezing again in 2022,indicating that Arctic daily warming events remain a concern.The NCEP/NCAR Reanalysis dataset...After approaching 0℃owing to an Atlantic storm at the end of 2015,the Arctic temperature approached freezing again in 2022,indicating that Arctic daily warming events remain a concern.The NCEP/NCAR Reanalysis dataset was used to investigate the influence of the NAO on the Arctic winter daily warming events induced by Atlantic storms,known as the Atlantic pattern-Arctic Rapid Tropospheric Daily Warming(Atlantic-RTDW)event.Atlantic-RTDW events are triggered by Atlantic storms that transport warm and humid air masses moving into the Arctic.Furthermore,an interdecadal change in the influence of NAO on Atlantic-RTDW-event frequency was observed around the mid-1980s.Specifically,before the mid-1980s(pre-transition period),500-hPa southerly(northerly)wind anomalies occupied the North Atlantic(NA)in the positive(negative)phase of NAO,which increased(decreased)the Atlantic-RTDW events occurrence by steering Atlantic storms into(away from)the Arctic;thus,the NAO could potentially influence the Atlantic-RTDW-event frequency.However,the relationship between the NAO and the Atlantic-RTDW-event frequency has weakened since the mid-1980s(post-transition period).In the post-transition period,such 500-hPa southerly(northerly)wind anomalies over the NA hardly existed in the positive(negative)phase of NAO,which was attributed to a stronger Atlantic Storm Track(AST)activity intensity than that in the pre-transition period.During this period,the strong AST induced an enhanced NAOrelated cyclone via transient eddy-mean flow interactions,resulting in the disappearance of southerly and northerly wind anomalies over the NA.展开更多
基金financially supported by the Postdoctor Research Foundation of Shunde Graduate School of University of Science and Technology Beijing(No.2022 B H003)。
文摘Machine-learning and big data are among the latest approaches in corrosion research.The biggest challenge in corrosion research is to accurately predict how materials will degrade in a given environment.Corrosion big data is the application of mathematical methods to huge amounts of data to find correlations and infer probabilities.It is possible to use corrosion big data method to distinguish the influence of the minimal changes of alloying elements and small differences in microstructure on corrosion resistance of low alloy steels.In this research,corrosion big data evaluation methods and machine learning were used to study the effect of Sb and Sn,as well as environmental factors on the corrosion behavior of low alloy steels.Results depict corrosion big data method can accurately identify the influence of various factors on corrosion resistance of low alloy and is an effective and promising way in corrosion research.
基金supported by the funds from the National Natural Science Foundation of China(Grant No.81871359 and No.81800445).
文摘Acute myocardial infarction(AMI)is a severe cardiovascular disease.This study aimed to identify crucial microRNAs(miRNAs)and mRNAs in AMI by establishing a miRNA-mRNA network.The microarray datasets GSE31568,GSE148153,and GSE66360 were downloaded from the Gene Expression Omnibus(GEO)database.We identified differentially expressed miRNAs(DE-miRNAs)and mRNAs(DE-mRNAs)in AMI samples compared with normal control samples.The consistently changing miRNAs in both GSE31568 and GSE148153 datasets were selected as candidate DE-miRNAs.The interactions between the candidate DE-miRNAs and DE-mRNAs were analyzed,and a miRNA-mRNA network and a protein-protein interaction network were constructed,along with functional enrichment and pathway analyses.A total of 209 DE-miRNAs in the GSE31568 dataset,857 DE-miRNAs in the GSE148153 dataset,and 351 DE-mRNAs in the GSE66360 dataset were identified.Eighteen candidate DE-miRNAs were selected from both the GSE31568 and GSE148153 datasets.Furthermore,miR-646,miR-127-5p,miR-509-5p,miR-509-3-5p,and miR-767-5p were shown to have a higher degree in the miRNA-mRNA network.THBS-1 as well as FOS was a hub gene in the miRNA-mRNA network and the protein-protein interaction(PPI)network,respectively.CDKN1A was important in both miRNA-mRNA network and PPI network.We established a miRNA-mRNA network in AMI and identified five miRNAs and three genes,which might be used as biomarkers and potential therapeutic targets for patients with AMI.
文摘Dielectric barrier discharge(DBD) is utilized to decompose xylene vapor in mobile gas under normal atmospheric pressure.The plasma is generated by an AC power source with a frequency of 6 kHz.In the experiment,the discharge power on the DBD reactor was calculated by a Lissajous figure,and the specific input energy(SIE) of different discharge voltage or residence time was obtained.The concentrations of xylene,carbon monoxide and carbon dioxide in the gas were analyzed by gas chromatography.The spectra of DBD were diagnosed using a spectrometer.We calculated the conversion rate(CR),mineralization rate(MR) and carbon dioxide selectivity.The relationship between these quantities and the SIE was analyzed.The experimental results show that high concentration xylene can be decomposed mostly by DBD plasma.The CR can reach as high as 90%with the main product of carbon dioxide.
基金Supported by the Key Program of Science and Technology Innovation in Ningbo (No.2019B10009)the National Natural Science Foundation of China (No.41476111)。
文摘The quantitative realtime polymerase chain reaction(RT-qPCR)is a powerful and sensitive method to measure expression of targeted gene but it highly relies on the use of suitable reference genes for data normalization.We evaluated the expressions of 8 housekeeping genes:18S ribosomal rDNA(18S rDNA),28S ribosomal r DNA(28S rDNA),rubisco large subunit(rbc-L),β-actin(ACT),glyceraldehyde-3-phosphate dehydrogenase(GAPDH),elongation factor 1(EF1),β-tubulin(Tub B),and P-phycoerythrin B(PEB),to select the suitable reference genes for different life-history stages(tetrasporophyte,carposporophyte,and male/female gametophyte)of Gracilaria vermiculophylla by absolute quantitative method.Softwares geNorm and BestKeeper were used to verify the results acquired from copy number analysis.Results show that the expression of identified reference genes varied in comparing groups composed of different type of life stages.It is suggested that 18S rDNA and TubB could be used for highly complex samples composed of mixed ploidy and phases.18S rDNA and 28S rDNA were also preferred for using among the matured isomorphic samples.But for samples with different maturities,TubB and ACT were recommended for tetrasporophytes and gametophytes respectively.
基金This work is supported by the open foundation of State Key Laboratory of Chemical Engineering(SKL-ChE-18B03)the Municipal Science and Technology Commission of Tianjin,China under Contract No.2009ZCKFGX01900.
文摘The particle collision behavior and heat transfer performance are investigated to reveal the heat transfer enhancement and fouling prevention mechanism in a Na_(2)SO_(4) circulating fluidized bed evaporator.The particle collision signals are analyzed with standard deviation by varying the amount of added particles ε(1%–3%),circulation flow velocity u(0.37–1.78 m·s^(-1)),and heat flux q(7.29–12.14 kW·m^(-2)).The results show that the enhancement factor reach up to 14.6%by adding polytetrafluoroethylene particles at ε=3%,u=1.78 m·s^(-1),and q=7.29 kW·m^(-2).Both the standard deviation of the particle collision signal and enhancement factor increase with the increase in the amount of added particles.The standard deviation increases with the increase in circulation flow velocity;however,the enhancement factor initially decreases and then increases.The standard deviation slightly decreases with the increase in heat flux at low circulation flow velocity,but initially increases and then decreases at high circulation flow velocity.The enhancement factor decreases with the increase in heat flux.The enhancement factor in Na_(2)SO_(4) solution is superior to that in water at high amount of added particles.The empirical correlation for heat transfer is established,and the model results agree well with the experimental data.
文摘The superior vena cava(SVC)is the main component of non-pulmonary vein(PV)ectopy in patients with atrial fibrillation(AF).Researchers have found that epicardial adipose tissue(EAT)volume is related to the AF substrate,which can be defined by the low voltage area(LVA).This study aimed to investigate the relationship between SVC-EAT and SVC-AF.Twenty-six patients with SVC-AF triggers were identified as the SVC-AF group.Other three groups were defined and included as the LVA-AF group(LVA>5%),non-LVA-AF group(LVA<5%),and physical examination(PE)group.EAT around left atrium(LA-EAT)and SVC-EAT volumes were obtained using a cardiac risk assessment module.According to the SVC/LA-EAT ratio,there are significant differences between the SVC-AF group and the three control groups(the SVC-AF group 0.092±0.041 vs.the LVA-AF group 0.054±0.026,the non-LVA-AF group 0.052±0.022,and the PE group 0.052±0.019,all P<0.001).Receiver operating characteristic curve analysis suggests the optimal cut-off point of SVC/LA-EAT ratio is 6.8%for detecting SVC-AF patients,with 81.1%sensitivity,73.1%specificity,and an area under the curve of 0.83(95%confidence interval,0.75-0.91).Those with SVC-AF have a higher SVC/LA-EAT ratio and empirical SVC isolation could be considered if the SVC/LA-EAT ratio was over 6.8%.
文摘In order to analyze the microscopic theory of viscous-elastic fluid flooding residual oil, the flow equation of polymer solution in the micro pore can be derived by selecting upper-convected Maxwell constitutive equation, continuity equation and motion equation. Then, the flow velocity field and stress field can be calculated under the boundary condition, and with the theory of stress tensor, the horizontal stress difference of polymer solution acting on the residual oil can be calculated. The results show that the greater the elasticity of viscous-elastic fluid is, the wider the flow channel is, the greater the horizontal stress difference is. The force acting on residual oil by viscous-elastic fluid can be increased by increasing the concentration of the polymer solution.
文摘To take full advantage of the natural hazel resources and improve its yield and quality in Great Xing’an Ridge region, we carried out an initial investigation. The result showed that: there are two species in this area: Corylus heterophlla and Corylus mandshurica. They mainly distribute from south of XinLin town, HuMa county, Heilongjiang province to south boundary of Great Xing’ an Ridge in mountain and hilly areas. Most of hazel in this area was under the state of natural growth with no scientific man-management. Soil where Corylus heterophlla grew was about 40 cm to 50 cm and Corylus mandshurica was 30 cm to 45 cm. The main plant disease was powdery mildew and insect pest were Curculio dieckmani, Zeuzera sp. and Faust Cockchafer. 100-seed weight of Corylus heterophylla was more than twice of Corylus mandshuria. However, Corylus mandshuria was plumper, had much more kernel and much less empty shell than Corylus heterophylla, and what’s more, shell sickness of it turned to be significantly thinner than Corylus heterophylla, all of which showed great cultivation value and economic commodity value.
文摘Objective:To study the effective value of introducing the concept of early oral exercise in the process of nursing intervention for preterm infants in the neonatal intensive care unit(NICU).Methods:96 cases of preterm infants diagnosed from January 2022 to August 2022 were selected and randomly divided into two groups:the general practice group(general nursing intervention),and the early practice group(early oral exercise intervention),and the effect of intervention on preterm infants in the two groups was observed.Results:After nursing care,the mean value of the non-nutritive sucking ability assessment(76.54±5.82),the mean value of the intellectual development degree assessment(104.57±8.45),the mean value of the psychomotor development degree assessment(102.33±6.74),and the mean value of behavioral neural reflexes ability assessment(38.71±2.40)in the early practice group were better than that as compared to the general practice group(P<0.05);the mean value of oral feeding start time of preterm infants in the early practice group(35.42±7.63)weeks,the mean value of all oral feeding time(34.12±5.28)weeks,and the mean time of hospital intervention(15.33±4.25)days were lesser than compared to those of the general practice group at 37.4±5.82 weeks,37.46±3.55 weeks,and 20.46±2.91 days,respectively(P<0.05);the rate of adverse reactions in preterm infants in the early practice group significantly lower than that of the general practice group(P<0.05).Conclusion:The introduction of the concept of early oral exercise intervention among NICU nurses improved the feeding effect,sucking ability of preterm infants,and intellectual development.Hence,early oral motor care should be popularized.
基金supported by the Guangdong Grant Key Technologies for Treatment of Brain Disorders,China,No. 2018B030332001 (to GC)the Guangzhou Key Projects of Brain Science and Brain-Like Intelligence Technology,No. 20200730009 (to YX)the Guangdong Basic and Applied Basic Research Foundation,No. 2020A1515110898 (to WYC)。
文摘The onset of retinal degenerative disease is often associated with neuronal loss. Therefore, how to regenerate new neurons to restore vision is an important issue. NeuroD1 is a neural transcription factor with the ability to reprogram brain astrocytes into neurons in vivo. Here, we demonstrate that in adult mice, NeuroD1 can reprogram Müller cells, the principal glial cell type in the retina, to become retinal neurons. Most strikingly, ectopic expression of NeuroD1 using two different viral vectors converted Müller cells into different cell types. Specifically, AAV7 m8 GFAP681::GFP-ND1 converted Müller cells into inner retinal neurons, including amacrine cells and ganglion cells. In contrast, AAV9 GFAP104::ND1-GFP converted Müller cells into outer retinal neurons such as photoreceptors and horizontal cells, with higher conversion efficiency. Furthermore, we demonstrate that Müller cell conversion induced by AAV9 GFAP104::ND1-GFP displayed clear dose-and time-dependence. These results indicate that Müller cells in adult mice are highly plastic and can be reprogrammed into various subtypes of retinal neurons.
文摘Understanding cardiac blood flow behaviors is of importance for cardiovascular research and clinical assessment of ventricle functions.Patient-specific Echo-based left ventricle(LV)fluid-structure interaction(FSI)models were introduced to perform ventricle mechanical analysis,investigate flow behaviors,and evaluate the impact of myocardial infarction(MI)and hypertension on blood flow in the LV.Echo image data were acquired from 3 patients with consent obtained:one healthy volunteer(P1),one hypertension patient(P2),and one patient who had an inferior and posterior myocardial infarction(P3).The nonlinear Mooney-Rivlin model was used for ventricle tissue with material parameter values chosen to match echo-measure LV volume data.Using the healthy case as baseline,LV with MI had lower peak flow velocity(30%lower at beginejection)and hypertension LV had higher peak flow velocity(16%higher at begin-filling).The vortex area(defined as the area with vorticity>0)for P3 was 19%smaller than that of P1.The vortex area for P2 was 12%smaller than that of P1.At peak of filling,the maximum flow shear stress(FSS)for P2 and P3 were 390%higher and 63%lower than that of P1,respectively.Meanwhile,LV stress and strain of P2 were 41%and 15%higher than those of P1,respectively.LV stress and strain of P3 were 36%and 42%lower than those of P1,respectively.In conclusion,FSI models could provide both flow and structural stress/strain information which would serve as the base for further cardiovascular investigations related to disease initiation,progression,and treatment strategy selections.Large-scale studies are needed to validate our findings.
基金supported by the National Natural Science Foundation of China(32270263)the Shandong Provincial Natural Science Foundation(ZR2022QC095,ZR2020MC023,ZR2022MC019).
文摘Starch is a major storage carbohydrate in plants and is critical in crop yield and quality.Starch synthesis is intricately regulated by internal metabolic processes and external environmental cues;however,the precise molecular mechanisms governing this process remain largely unknown.In this study,we revealed that high red to far-red(high R:FR)light significantly induces the synthesis of leaf starch and the expression of synthesis-related genes,whereas low R:FR light suppress these processes.Arabidopsis phytochrome B(phyB),the primary R and FR photoreceptor,was identified as a critical positive regulator in this process.Downstream of phyB,basic leucine zipper transcription factor ELONGATED HYPOCOTYL5(HY5)was found to enhance starch synthesis,whereas the basic helix-loop-helix transcription factors PHYTOCHROME INTERACTING FACTORs(PIF3,PIF4,and PIF5)inhibit starch synthesis in Arabidopsis leaves.Notably,HY5 and PIFs directly compete for binding to a shared G-box cis-element in the promoter region of genes encoding starch synthases GBSS,SS3,and SS4,which leads to antagonistic regulation of their expression and,consequently,starch synthesis.Our findings highlight the vital role of phyB in enhancing starch synthesis by stabilizing HY5 and facilitating PIFs degradation under high R:FR light conditions.Conversely,under low R:FR light,PIFs predominantly inhibit starch synthesis.This study provides insight into the physiological and molecular functions of phyB and its downstream transcription factors HY5 and PIFs in starch synthesis regulation,shedding light on the regulatory mechanism by which plants synchronize dynamic light signals with metabolic cues to module starch synthesis.
文摘Current guidelines encourage large studies in a diverse population to establish normal reference ranges for three-dimensional(3D)echocardiography for different ethnic groups.This study was designed to establish the normal values of 3D-left ventricular(LV)and left atrial(LA)volume and function in a nationwide,population-based cohort of healthy Han Chinese adults.A total of 1117 healthy volunteers aged 18–89 years were enrolled from 28 collaborating laboratories in China.Two sets of 3D echocardiographic instruments were used,and full-volume echocardiographic images were recorded and transmitted to a core laboratory for image analysis with a vendor-independent off-line workstation.Finally,866 volunteers(mean age of 48.4 years,402 men)were qualified for final analysis.Most parameters exhibited substantial differences between different sex and age groups,even after indexation by body surface area.The normal ranges of 3D-LV and 3D-LA volume and function differed from those recommended by the American Society of Echocardiography and the European Association of Cardiovascular Imaging guidelines,presented by the World Alliance Societies of Echocardiography(WASE)study,and from the 2D values in the EMINCA study.The normal reference values of 3D echocardiography-derived LV and LA volume and function were established for the first time in healthy Han Chinese adults.Normal ranges of 3D-LV and 3D-LA echocardiographic measurements stratified with sex,age,and race should be recommended for clinical applications.
基金supported by National Natural Science Foundation of China(41675066)Anhui Provincial Natural Science Foundation(1908085MD108)。
文摘After approaching 0℃owing to an Atlantic storm at the end of 2015,the Arctic temperature approached freezing again in 2022,indicating that Arctic daily warming events remain a concern.The NCEP/NCAR Reanalysis dataset was used to investigate the influence of the NAO on the Arctic winter daily warming events induced by Atlantic storms,known as the Atlantic pattern-Arctic Rapid Tropospheric Daily Warming(Atlantic-RTDW)event.Atlantic-RTDW events are triggered by Atlantic storms that transport warm and humid air masses moving into the Arctic.Furthermore,an interdecadal change in the influence of NAO on Atlantic-RTDW-event frequency was observed around the mid-1980s.Specifically,before the mid-1980s(pre-transition period),500-hPa southerly(northerly)wind anomalies occupied the North Atlantic(NA)in the positive(negative)phase of NAO,which increased(decreased)the Atlantic-RTDW events occurrence by steering Atlantic storms into(away from)the Arctic;thus,the NAO could potentially influence the Atlantic-RTDW-event frequency.However,the relationship between the NAO and the Atlantic-RTDW-event frequency has weakened since the mid-1980s(post-transition period).In the post-transition period,such 500-hPa southerly(northerly)wind anomalies over the NA hardly existed in the positive(negative)phase of NAO,which was attributed to a stronger Atlantic Storm Track(AST)activity intensity than that in the pre-transition period.During this period,the strong AST induced an enhanced NAOrelated cyclone via transient eddy-mean flow interactions,resulting in the disappearance of southerly and northerly wind anomalies over the NA.