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Genetic Mapping of Grain Length-and Width-Related Genes in the Local Wheat Variety Guizi 1×Zhongyan 96-3 Hybrid Population Using Genome Sequencing
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作者 ShaoyanWu Jie Tian +6 位作者 YiyanWang Muhammad Arif ShuyaoWang JingWang Zhuoyao Yang Ruhong Xu Luhua Li 《Phyton-International Journal of Experimental Botany》 2025年第12期3913-3924,共12页
Wheat grain morphology,particularly grain length(GL)and width(GW),is a key determinant of yield.To improve the suboptimal grain dimensions of the local anthocyanin-rich variety Guizi 1(GZ1),we crossed it with Zhongyan... Wheat grain morphology,particularly grain length(GL)and width(GW),is a key determinant of yield.To improve the suboptimal grain dimensions of the local anthocyanin-rich variety Guizi 1(GZ1),we crossed it with Zhongyan 96-3(ZY96-3),an elite germplasm known for faster grain filling and superior grain size.A genotyping-by-sequencing(GBS)approach was applied to an F_(2)population of 110 individuals derived from GZ1×ZY96-3,resulting in the identification of 23,134 high-quality SNPs.Most of the SNPs associated with GL and GW were clustered on chromosomes 2B,3A,and 3B.QTL mapping for GL revealed two major loci,GL1 on chromosome 2B and GL2 on chromosome 3B,and eight candidate genes were identified within their corresponding intervals(2B:63.6–70.4 Mb;3B:631.5–633.3 Mb).These genes encode proteins potentially involved in grain size regulation,including a TOR2 regulation-associated protein,erect spike 2(EP2),fibroblast growth factor 6(FGF6),cellulose synthase-like(CSLD),RelA/pot homologue three family protein,and three GDSL esterase/lipase(GLIP)proteins.Additionally,we detected a QTL associated with GW on chromosome 3A and identified two candidate genes,TOR2 regulation and starch synthase within the 61.4–68.5 Mb interval.Overall,this study provides a strong theoretical and technical basis for wheat genetic improvement and offers valuable resources for precise QTL mapping and candidate gene discovery. 展开更多
关键词 WHEAT grain length grain width genotyping-by-sequencing(GBS) QTL mapping SNP markers candidate genes Guizi 1 Zhongyan 96-3
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Tropical cyclone secondary eyewall width modulation:Differential impacts of surface environmental wind-vertical shear alignment and counter-alignment configurations
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作者 Yingying Zheng Qingqing Li Yufan Dai 《Atmospheric and Oceanic Science Letters》 2026年第1期7-13,共7页
This study investigates the width of the secondary eyewall(SE)immediately following its formation in tropical cyclones with surface environmental winds aligned and counter-aligned with environmental vertical wind shea... This study investigates the width of the secondary eyewall(SE)immediately following its formation in tropical cyclones with surface environmental winds aligned and counter-aligned with environmental vertical wind shear(VWS),using idealized numerical experiments.Results reveal that the SE develops greater radial extent when surface winds align with VWS compared to counter-aligned conditions.In alignment configurations,shear-enhanced surface winds on the right flank amplify surface enthalpy fluxes,thereby elevating boundary-layer entropy within the downshear outer-core region.Subsequently,more vigorous outer rainbands develop,inducing marked acceleration of tangential winds in the outer core preceding SE formation.The resultant radial expansion of supergradient winds near the boundary-layer top triggers widespread convective activity immediately beyond the inner core.Progressive axisymmetrization of this convective forcing ultimately generates an expansive SE structure. 展开更多
关键词 Tropical cyclone Secondary eyewall width Precipitation Vertical wind shear
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Photoacoustic imaging and main lobe width analysis for enhancing microwave ablation monitoring of liver tissue
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作者 Min Wan Yameng Zhang +4 位作者 Shihao Tang Zhiyu Qian Fan Gao Yamin Yang Weitao Li 《Journal of Innovative Optical Health Sciences》 2026年第2期129-140,共12页
Microwave ablation(MWA)is a minimally invasive technique for treating hepatic tumors,necessitating precise monitoring to ensure treatment efficacy and minimize damage to surrounding tissues.This study explores the pot... Microwave ablation(MWA)is a minimally invasive technique for treating hepatic tumors,necessitating precise monitoring to ensure treatment efficacy and minimize damage to surrounding tissues.This study explores the potential of photoacoustic imaging(PAI)in monitoring MWA by examining ex vivo porcine liver tissues.In this study,a comprehensive analysis of photoacoustic signals was performed to compare the main lobe width(MLW)between ablated and normal regions in porcine liver tissue.Histological staining with succinate dehydrogenase(SDH)and shear wave elastography(SWE)were employed to validate the changes in tissue elasticity after ablation.The analysis demonstrated a notable reduction in the MLW of the average A-lines in ablated tissues compared to nonablated regions(p<0.01).This reduction,attributed to increased tissue density and enhanced elasticity,indicates accelerated sound propagation in thermally ablated areas,which then serves as a critical parameter for mapping tissue characteristics.The reconstruction of the MLW distribution successfully delineated the ablated regions,and was consistent with the results of SDH staining and SWE.In addition,MLW-based imaging exhibited higher spatial resolution compared to SWE.Incorporating MLW analysis into PAI may be a promising strategy to improve the accuracy and effectiveness of MWA monitoring in clinical settings. 展开更多
关键词 Photoacoustic imaging main lobe width microwave ablation tissue density shear wave elastography
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Influence of Soft Segment Length on the Dielectric Polarization Behavior of Ketal-containing Polyurethane Elastomer
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作者 Xue Mei Wan Lu +6 位作者 Jian-Rong Dong Ke-Heng Pan Jun-Jie Tan Hong-Ye Yan Jun Wu Yu Zhou Hong-Xiang Chen 《Chinese Journal of Polymer Science》 2026年第1期189-197,I0015,共10页
Polyurethane elastomers exhibit high dielectric constants owing to their polar groups,and can be used as energy storage capacitors.Energy storage depends not only on the dielectric constant but also on the dielectric ... Polyurethane elastomers exhibit high dielectric constants owing to their polar groups,and can be used as energy storage capacitors.Energy storage depends not only on the dielectric constant but also on the dielectric loss.However,the relationship between chain structure and dielectric properties is not yet clear.Ketal-containing crosslinked polyurethane elastomers were prepared using cyclic ketal diol as a chain extender.The effect of the soft segment length on the dielectric properties and energy storage was investigated.The cause of the change in the dipolar polarization with the soft segment length was analyzed.As the soft segment length increased,the hard-soft hydrogen bonding decreased,whereas the hard-hard hydrogen bonding increased.Under the action of an electric field,the polar bonds in the ketal-containing polyurethane elastomer overcome the hydrogen bonding between hard-soft segments to produce polarization;meanwhile,they also experience crankshaft motions to generate polarization.The former has a relatively high relaxation activation energy of approximately 10-20 k J·mol^(-1),resulting in a large dielectric loss.The latter has a relatively low relaxation activation energy,approximately 0.7-1.7 kJ·mol^(-1),leading to low dielectric loss.As a result,the dielectric constant showed a decreasing trend,and the dielectric loss gradually decreased.This study provides a theoretical foundation for improving the dielectric properties of polyurethane elastomers. 展开更多
关键词 Dielectric polarization Polyurethane elastomer Soft segment length Intermolecular interaction
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Experimental and theoretical study of the smoke back-layering length in a tunnel with cross-passage:effects of longitudinal fire source locations
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作者 Zhisheng Li Yuchun Zhang +2 位作者 Maozhen Qiao Yunji Gao Yule Huang 《Railway Engineering Science》 2026年第1期184-199,共16页
The diversion effect caused by the linked structure in a metro tunnel with cross-passage complicates the impact of longitudinal fire source location on the smoke backflow layering behavior that has not been clarified,... The diversion effect caused by the linked structure in a metro tunnel with cross-passage complicates the impact of longitudinal fire source location on the smoke backflow layering behavior that has not been clarified,despite the fact that the scenario exists in practice.A series of laboratory-scale experiments were conducted in this study to investigate the smoke back-layering length in a model tunnel with cross-passage.The heat release rate,the velocity of longitudinal air flow,and the location of the fire source were all varied.It was found that the behavior of smoke backflow for the fire source located at the upstream of bifurcation point resembles a single-hole tunnel fire.As the fire source’s position shifts downstream from the bifurcation point,the length of smoke back-layering progressively increases.A competitive interaction exists between airflow diversion and smoke diversion during smoke backflow,significantly affecting the smoke back-layering length in the main tunnel.The dimensionless smoke back-layering length model was formulated in a tunnel featuring a cross-passage,taking into account the positions of longitudinal fire sources.The dimensionless smoke back-layering length exhibits a positive correlation with the 17/18 power of total heat release rate Q and a negative correlation with the 5/2 power of longitudinal ventilation velocity V. 展开更多
关键词 Tunnel fire Cross-passage Smoke back-layering length Fire source location Longitudinal ventilation
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Impacts of 1.5℃ and 2.0℃ Global Warming on the Onset,Cessation,and Length of the Rainy Season in Global Land Monsoon Regions
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作者 Thierry N.TAGUELA Ibraheem RAJI +4 位作者 Akintomide A.AKINSANOLA Priyanshi SINGHAI Oluwafemi E.ADEYERI Caroline M.WAINWRIGHT Rondrotiana BARIMALALA 《Advances in Atmospheric Sciences》 2026年第1期87-102,共16页
The onset,cessation,and length of the rainy season are crucial for global water resources,agricultural practices,and food security.However,the response of precipitation seasonality to global warming remains uncertain.... The onset,cessation,and length of the rainy season are crucial for global water resources,agricultural practices,and food security.However,the response of precipitation seasonality to global warming remains uncertain.In this study,we analyze how global warming levels(GWLs)of 1.5℃ and 2℃ could affect the timing of rainfall onset(RODs),rainfall cessation(RCDs),and the overall duration of the rainy season(LRS)over global land monsoon(GLM)regions using simulations from CMIP6 under the SSP2-4.5 and SSP5-8.5 scenarios.With high model consensus,our results reveal that RODs are projected to occur later over Southern Africa,North Africa,and South America,but earlier over South Asia and Australia,in a warmer climate.The projected early RODs in Australia are more pronounced at the 2℃ GWL under SSP5-8.5.On the other hand,early RCDs are projected over South America and East Asia,while late RCDs are projected over North Africa,with high inter-model agreement.These changes are associated with a future decrease in LRS in most GLM regions.Additionally,we found that continuous warming over 1.5℃ will further reduce the length of the rainy season,especially over the South America,North Africa,and Southern Africa monsoon regions.The findings underscore the urgent need to mitigate global warming. 展开更多
关键词 rainfall onset rainfall cessation global land monsoon rainy season length CMIP6 projections global warming levels
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Accurate Interconnection Length and Routing Channel Width Estimates for FPGAs
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作者 高海霞 马晓华 杨银堂 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第7期1196-1200,共5页
We study the problem of the prediction of interconnection dimensions for FPGAs, including estimating interconnection length and channel width. Experimental results show that our estimates are more accurate than those ... We study the problem of the prediction of interconnection dimensions for FPGAs, including estimating interconnection length and channel width. Experimental results show that our estimates are more accurate than those of existing methods. 展开更多
关键词 FPGA interconnection length estimation channel width estimation
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Sensitivity analysis of the vane length and passage width for a radial type swirler employed in a triple swirler configuration 被引量:4
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作者 Foad Vashahi Shahnaz Rezaei +1 位作者 Reza Alidoost Dafsari Jeekeun Lee 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2019年第6期363-375,共13页
The design of axial or radial swirlers typically governs a number of geometrical parameters that are determined by the desired flow field.In the meantime,the number of unknown parameters increases with the number of c... The design of axial or radial swirlers typically governs a number of geometrical parameters that are determined by the desired flow field.In the meantime,the number of unknown parameters increases with the number of concentrically mounted swirlers.The available literature is nonetheless limited,and designers are obligated to increase the number of initial assumptions.In this article,three kinds of triple swirlers are employed and simulations are performed to determine the effect of each parameter on the swirler performance.Based on the correlation provided,overlengthening the radial vane length could result in significant changes in the flow field from the jetlike pattern to a wide swirl-jet angle due to the Coanda effect.Passage width should also have the potential to alter the swirl-jet angle and velocity field at the exit of the swirler. 展开更多
关键词 TRIPLE SWIRLER SWIRLER design RADIAL VANE length PASSAGE width Reynolds averaged Navier–Stokes
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The Paradigm of Surgical Ellipse Dimensions: Are the Length-to-Width Ratio of 3 to 4 and a Vertex Angle of 30&ordm;Correct?
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作者 Tamara R. Tilleman M. M. Tilleman M. H. A. Neumann 《Surgical Science》 2013年第4期236-240,共5页
Background: It has been postulated that elliptical cutaneous excisions must possess a length-to-width ratio of 3 to 4 and a vertex angle of 30o or less in order to be closed primarily without creating a “dog ear”. T... Background: It has been postulated that elliptical cutaneous excisions must possess a length-to-width ratio of 3 to 4 and a vertex angle of 30o or less in order to be closed primarily without creating a “dog ear”. These dimensions became axiomatic in cutaneous surgery and have been taught in the apprenticeship model for years. The present article examines the validity of that paradigm. Methods: We collected data from two sources: ellipses described in the literature (57 cases);and elliptical excisions performed at the authors’ outpatient clinic (83 cases). The surgical ellipse lengths, widths, and vertex angles were analyzed, and the data were compared to a mathematical formula used to generate a fusiform ellipse. Results: The length-to-width ratio of 3 - 4 was found to be inconsistent with the recommended vertex angle of 30o. In fact, a length-to-width ratio of 3 - 4 determines a vertex angle of 48o - 63o. A 30o vertex angle is only feasible with long length-to-width ration of about 7.5. Conclusions: The paradigm that surgical ellipses should have a vertex angle of 30o with length-to-width ratio of 3 - 4 is incorrect. Evidence from actual surgical practice and from mathematical formulation shows that either the length-to-width ratio must be larger than 3 - 4 or the vertex angle must be larger than 30 degrees. 展开更多
关键词 Elliptical Excision length-to-width RATIO of 3 - 4 30o Vertex Angle
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Impact of Channel Length and Width for Charge Transportation of Graphene Field Effect Transistor
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作者 Kamal Hosen Md.Rasidul Islam Kong Liu 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第6期757-763,I0003,共8页
The effect of channel length and width on the large and small-signal parameters of the graphene field effect transistor have been explored using an analytical approach.In the case of faster saturation as well as extre... The effect of channel length and width on the large and small-signal parameters of the graphene field effect transistor have been explored using an analytical approach.In the case of faster saturation as well as extremely high transit frequency,the graphene field effect transistor shows outstanding performance.From the transfer curve,it is observed that there is a positive shift of Dirac point from the voltage of 0.15 V to 0.35 V because of reducing channel length from 440 nm to 20 nm and this curve depicts that graphene shows ambipolar behavior.Besides,it is found that because of widening channel the drain current increases and the maximum current is found approximately 2.4 mA and 6 mA for channel width 2μm and 5μm respectively.Furthermore,an approximate symmetrical capacitance-voltage(C-V)characteristic of the graphene field effect transistor is obtained and the capacitance reduces when the channel length decreases but the capacitance can be increased by raising the channel width.In addition,a high transconductance,that demands high-speed radio frequency(RF)applications,of 6.4 mS at channel length 20 nm and 4.45 mS at channel width 5μm along with a high transit frequency of 3.95 THz have been found that demands high-speed radio frequency applications. 展开更多
关键词 GRAPHENE Graphene field effect transistor Large signal Small-signal Channel length Channel width
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Effect of Overlap Stress as Well as Tie Beam Length and Width on Settlement of Isolated Footings Using Finite Element
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作者 Mahmoud Abo Bakr El Sideek 《Open Journal of Civil Engineering》 2014年第1期35-44,共10页
Effects of tie beam length, width and overlap stress on settlement of foundations have been investigated. In this investigation square concrete footings have been used with dimensions (B × B × d) where (d) i... Effects of tie beam length, width and overlap stress on settlement of foundations have been investigated. In this investigation square concrete footings have been used with dimensions (B × B × d) where (d) is footing depth and (B) is footing width (1, 1.5,2 m). Width of tie beam (b) has been taken equal to 0.25, 0.30, 0.40, 0.50 and 0.75 (m). Tie beam length (L) has been taken varying from B till 3B with same footing depth = 0.50 m. Effect of overlap stress on settlement as well as effect of tie beam width and length on settlement has been determined. Also, the efficiency of tie beam length and width has been obtained. An equation is presented to compute the overlap stress zone in case of existing tie beam. It is found that the settlement increases with increasing the length of tie beam which is clear after the effect of the overlap stresses zone. The width of overlap stress zone case of existing tie beam has been found to be equal to (1.6 -1.75) B. The settlement of footings decreases with increasing tie beam width. It is found that the settlement after the effect of the overlap stress zone increases with increasing the length of tie beam. 展开更多
关键词 Effect OVERLAP Stress Tie Beam length and width SETTLEMENT ISOLATED FOOTINGS Finite Element
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Genetic Analysis of Leaf Length and Leaf Width in Bitter Gourd
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作者 Ziji LIU Yu NIU +1 位作者 Yan YANG Baibi ZHU 《Medicinal Plant》 CAS 2022年第6期78-80,共3页
[Objectives]To explore the genetic mechanism that leaf length and leaf width in bitter gourd has realistic guiding significance for formulating breeding strategy.[Methods]In this paper,the cross was made between CN19-... [Objectives]To explore the genetic mechanism that leaf length and leaf width in bitter gourd has realistic guiding significance for formulating breeding strategy.[Methods]In this paper,the cross was made between CN19-1 and Thai4-6 and an F2segregation population was constructed.The genetic characteristics of leaf length and leaf width were analyzed by employing the major gene plus polygene mixed genetic model.[Results]The data analysis results demonstrated that the leaf length and leaf width of the F_(2) segregation population showed continuous distribution.The optimum model for leaf length genetic analysis was A-1,the additive effect value of the major gene was 3.1766,the dominant effect value was-3.1766,and the heritability was 74.51%.The optimum model for leaf width genetic analysis was B-1.The additive effect values of 2 pairs of major genes controlling the leaf width were 3.1917 and 0.9623,respectively.The dominant effect values were-1.3135 and-0.3463,respectively.The additive×additive interaction effect was-0.3591,the additive×dominant interaction effect was-0.2570,the dominant×additive interaction effect was 1.9916,the dominant×dominant interaction effect was 1.9686.The heritability of major genes was 96.67%.[Conclusions]This study is expected to provide a theoretical basis for the breeding of bitter gourd. 展开更多
关键词 Bitter gourd Genetic model Leaf length Leaf width Genetic analysis
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The Bandwidth for a Class of k-caterpillars with Hairs of Equal Length
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作者 SONG Xiao-xin CHANG He 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期30-40,共11页
Utilizing Chvatal’s bandwidth lower bound on diameter,we could determnine the bandwidth for a class of k-caterpillars with hairs of equal length.
关键词 graphs LABELING BANDwidth k-caterpillars with hairs of equal length covering labeling symmetric labeling
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Predicting post-hepatectomy liver failure using a nomogram based on portal vein width,inflammatory indices,and the albumin-bilirubin score 被引量:1
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作者 Ke Sun Jiang-Bin Li +3 位作者 Ya-Feng Chen Zhong-Jie Zhai Lang Chen Rui Dong 《World Journal of Gastrointestinal Surgery》 2025年第2期87-96,共10页
BACKGROUND Post-hepatectomy liver failure(PHLF)after liver resection is one of the main complications causing postoperative death in patients with hepatocellular carcinoma(HCC).It is crucial to help clinicians identif... BACKGROUND Post-hepatectomy liver failure(PHLF)after liver resection is one of the main complications causing postoperative death in patients with hepatocellular carcinoma(HCC).It is crucial to help clinicians identify potential high-risk PHLF patients as early as possible through preoperative evaluation.AIM To identify risk factors for PHLF and develop a prediction model.METHODS This study included 248 patients with HCC at The Second Affiliated Hospital of Air Force Medical University between January 2014 and December 2023;these patients were divided into a training group(n=164)and a validation group(n=84)via random sampling.The independent variables for the occurrence of PHLF were identified by univariate and multivariate analyses and visualized as nomograms.Ultimately,comparisons were made with traditional models via receiver operating characteristic(ROC)curves,calibration curves,and decision curve analysis(DCA).RESULTS In this study,portal vein width[odds ratio(OR)=1.603,95%CI:1.288-1.994,P≤0.001],the preoperative neutrophil-to-lymphocyte ratio(NLR)(OR=1.495,95%CI:1.126-1.984,P=0.005),and the albumin-bilirubin(ALBI)score(OR=8.868,95%CI:2.144-36.678,P=0.003)were independent risk factors for PHLF.A nomogram prediction model was developed using these factors.ROC and DCA analyses revealed that the predictive efficacy and clinical value of this model were better than those of traditional models.CONCLUSION A new Nomogram model for predicting PHLF in HCC patients was successfully established based on portal vein width,the NLR,and the ALBI score,which outperforms the traditional model. 展开更多
关键词 NOMOGRAM Hepatocellular carcinoma Post-hepatectomy liver failure Albumin-bilirubin score Portal vein width
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Red blood cell distribution width to albumin ratio is correlated with prognosis of patients in coronary care unit 被引量:1
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作者 Jiao-Ni Wang Ze-Song Hu +1 位作者 Yong-Wei Yu Xiao-Hui Peng 《World Journal of Cardiology》 2025年第2期61-70,共10页
BACKGROUND As red blood cell distribution width(RDW)and albumin have been shown to be independent predictors of mortality from various diseases,this study aimed to investigate the effect of the RDW to albumin ratio(RA... BACKGROUND As red blood cell distribution width(RDW)and albumin have been shown to be independent predictors of mortality from various diseases,this study aimed to investigate the effect of the RDW to albumin ratio(RA)as an independent predictor of the prognosis of patients admitted to the coronary care unit(CCU).AIM To use the RDW and albumin level to predict the prognosis of patients in the CCU.METHODS Data were obtained from the Medical Information Mart Intensive Care III database.The primary outcome was 365-day all-cause mortality,whereas the secondary outcomes were 30-and 90-day all-cause mortality,hospital length of stay(LOS),and CCU LOS.Cox proportional hazards regression model,propen-sity score matching,and receiver operating characteristic curve analyses were used.RESULTS The hazard ratio(95%confidence interval)of the upper tertile(RA>4.66)was 1.62(1.29 to 2.03)when compared with the reference(RA<3.84)in 365-day all-cause mortality.This trend persisted after adjusting for demographic and clinical variables in the propensity score-matching analysis.Similar trends were observed for the secondary outcomes of hospital and CCU LOS.Receiver operating characteristic curve analysis was performed by combining the RA and sequential organ failure assessment(SOFA)scores,and the C-statistic was higher than that of the SOFA scores(0.733 vs 0.702,P<0.001).CONCLUSION RA is an independent prognostic factor in patients admitted to the CCU.RA combined with the SOFA score can improve the predictive ability of the SOFA score.However,our results should be verified in future prospective studies. 展开更多
关键词 Red blood cell distribution width ALBUMIN PROGNOSIS Coronary care unit
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Use of Prenasal Thickness,Nasal Bone Length and Their Ratio in Diagnosing Down Syndrome at 16-25 weeks'of gestation in India:A Retrospective,Observational,Case Control Study 被引量:1
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作者 Mhaske Nilesh Madhukar Rachna Gupta +2 位作者 Akshatha Sharma Smriti Prasad Anita Kaul 《iRADIOLOGY》 2025年第3期239-247,共9页
Background:It is found to have association of facial parameters with trisomy 21 fetuses(T 21).We have compared prenasal thickness(PNT),nasal bone length(NBL),and the PNT:NBL ratio of normal fetuses with fetuses with t... Background:It is found to have association of facial parameters with trisomy 21 fetuses(T 21).We have compared prenasal thickness(PNT),nasal bone length(NBL),and the PNT:NBL ratio of normal fetuses with fetuses with trisomy 21(T 21)between 16 and 25 weeks of gestation as a diagnostic tool for T 21.Methods:Facial profile images in the two dimensional(2D)gray scale were assessed to measure fetal NBL and PNT between 16 and 25 weeks of gestation.The PNT:NBL ratio of the fetuses was calculated.Nomograms were constructed from the data of morphologically normal fetuses at live birth.The PNT,NBL,and PNT:NBL ratio of fetuses with confirmed T 21(n=31)and morphologically normal fetuses at live birth(controls,n=3485)were compared.Results:Nomograms for PNT,NBL,and the PNT:NBL ratio were constructed.In T 21 fetuses,PNT(>95th percentile),NBL(<5th percentile),and the PNT:NBL ratio(>95th percentile)showed a sensitivity of 25%,29%,and 45%for PNT,NBL,and PNT:NBL,respectively,and specificity of 95%,96%,and 94%,for PNT,NBL,and PNT:NBL,respectively.All of these markers showed a negative predictive value of 99%.Conclusion:PNT,NBL,and the PNT:NBL ratio have high diagnostic value for fetuses with Down syndrome and can be incorporated easily in the current second trimester screening protocol for T 21.PNT,NBL,and the PNT:NBL ratio are more specific markers for Down syndrome than those used in previous studies. 展开更多
关键词 down syndrome nasal bone length pernasal thickness prenatal screening soft marker
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Risk Factors for Prolonged Postoperative Length of Stay After Hip Fracture Surgery in Very Elderly Patients 被引量:1
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作者 Bo-Wen Xu Wei-Yun Chen +3 位作者 Chen Sun Ling Lan Lu-Lu Ma Li-Jian Pei 《Chinese Medical Sciences Journal》 2025年第2期111-119,I0002,共10页
Objective To identify risk factors contributing to prolonged postoperative length of stay(LOS)in very elderly patients following hip fracture surgery,with a focus on postoperative complications and the impact of diffe... Objective To identify risk factors contributing to prolonged postoperative length of stay(LOS)in very elderly patients following hip fracture surgery,with a focus on postoperative complications and the impact of different anesthesia approaches.Methods This retrospective single-center cohort study enrolled patients aged 90 years or older who underwent hip fracture surgery at Peking Union Medical College Hospital between January 31,2013 and December 31,2023.Relevant perioperative data were collected.The primary outcome was postoperative LOS,and the study cohort was divided into two groups:postoperative LOS≤7 days and LOS>7 days.Logistic regression was performed to identify factors related to prolonged postoperative LOS.Results A total of 155 patients were included.The average age was 92.7±2.6 years.There were 73(47%)patients with postoperative LOS>7 days.Postoperative pneumonia was the only factor associated with a prolonged postoperative LOS(OR=2.12,95%CI[1.09,4.16],P=0.028).Neither the type of anesthesia(regional vs.general anesthesia,OR=1.00,95%CI[0.53,1.90],P=0.993)nor the method of airway management(laryngeal mask ventilation vs.spontaneous breathing,OR=1.46,95%CI[0.58,3.76],P=0.424;endotracheal intubation vs.spontaneous breathing,OR=0.82,95%CI[0.39,1.69],P=0.592)showed a significant association with a prolonged postoperative LOS.Preoperative chronic obstructive pulmonary disease(OR=2.78,95%CI[1.05,7.65],P=0.040)and preoperative neutrophil count(OR=1.13,95%CI[1.01,1.26],P=0.029)were both significantly associated with the occurrence of postoperative pneumonia,while anesthesia type and airway management method were not.Conclusions Postoperative pneumonia was associated with prolonged postoperative LOS in very elderly patients undergoing hip fracture surgery,whereas anesthesia types and airway management methods show no association with prolonged postoperative LOS or postoperative pneumonia.Preoperative comorbidities,especially respiratory conditions and systemic inflammation,potentially play a substantial role in postoperative recovery. 展开更多
关键词 very elderly hip fracture anesthesia type length of hospital stay postoperative pneumonia
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Pretreatment red blood cell distribution width as a predictive marker for postoperative complications after laparoscopic pancreatoduodenectomy
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作者 Xian-Rang Cao Yin-Long Xu +4 位作者 Jia-Wei Chai Kai Zheng Jun-Jie Kong Jun Liu Shun-Zhen Zheng 《World Journal of Gastrointestinal Oncology》 SCIE 2025年第1期143-157,共15页
BACKGROUND Red blood cell distribution width(RDW)is associated with the development and progression of various diseases.AIM To explore the association between pretreatment RDW and short-term outcomes after laparoscopi... BACKGROUND Red blood cell distribution width(RDW)is associated with the development and progression of various diseases.AIM To explore the association between pretreatment RDW and short-term outcomes after laparoscopic pancreatoduodenectomy(LPD).METHODS A total of 804 consecutive patients who underwent LPD at our hospital between March 2017 and November 2021 were retrospectively analyzed.Correlations between pretreatment RDW and clinicopathological characteristics and short-term outcomes were investigated.RESULTS Patients with higher pretreatment RDW were older,had higher Eastern Cooperative Oncology Group scores and were associated with poorer short-term outcomes than those with normal RDW.High pretreatment RDW was an independent risk factor for postoperative complications(POCs)(hazard ratio=2.973,95%confidence interval:2.032-4.350,P<0.001)and severe POCs of grade IIIa or higher(hazard ratio=3.138,95%confidence interval:2.042-4.824,P<0.001)based on the Clavien-Dino classification system.Subgroup analysis showed that high pretreatment RDW was an independent risk factor for Clavien-Dino classi-fication grade IIIb or higher POCs,a comprehensive complication index score≥26.2,severe postoperative pancreatic fistula,severe bile leakage and severe hemorrhage.High pretreatment RDW was positively associated with the neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio and was negatively associated with albumin and the prognostic nutritional index.CONCLUSION Pretreatment RDW was a special parameter for patients who underwent LPD.It was associated with malnutrition,severe inflammatory status and poorer short-term outcomes.RDW could be a surrogate marker for nutritional and inflammatory status in identifying patients who were at high risk of developing POCs after LPD. 展开更多
关键词 BIOMARKER Laparoscopic pancreatoduodenectomy Postoperative complication Red blood cell distribution width Short-term outcomes
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CNN-based multi-output regression model to estimate infrastructural surface crack dimensions adopting a generalised patch size and FWHM-based width quantification
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作者 Sudipta Debroy Arjun Sil 《Digital Twins and Applications》 2025年第1期75-102,共28页
To cater the need for real-time crack monitoring of infrastructural facilities,a CNN-regression model is proposed to directly estimate the crack properties from patches.RGB crack images and their corresponding masks o... To cater the need for real-time crack monitoring of infrastructural facilities,a CNN-regression model is proposed to directly estimate the crack properties from patches.RGB crack images and their corresponding masks obtained from a public dataset are cropped into patches of 256 square pixels that are classified with a pre-trained deep convolution neural network,the true positives are segmented,and crack properties are extracted using two different methods.The first method is primarily based on active contour models and level-set segmentation and the second method consists of the domain adaptation of a mathematical morphology-based method known as FIL-FINDER.A statistical test has been performed for the comparison of the stated methods and a database prepared with the more suitable method.An advanced convolution neural network-based multi-output regression model has been proposed which was trained with the prepared database and validated with the held-out dataset for the prediction of crack-length,crack-width,and width-uncertainty directly from input image patches.The pro-posed model has been tested on crack patches collected from different locations.Huber loss has been used to ensure the robustness of the proposed model selected from a set of 288 different variations of it.Additionally,an ablation study has been conducted on the top 3 models that demonstrated the influence of each network component on the pre-diction results.Finally,the best performing model HHc-X among the top 3 has been proposed that predicted crack properties which are in close agreement to the ground truths in the test data. 展开更多
关键词 ablation CNN convolution neural network CRACK crack patch estimation FWHM length multi-output regression segmentation uncertainty width
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Widely tunable/wavelength-swept SLM fiber laser with ultra-narrow linewidth and ultra-high OSNR 被引量:3
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作者 冯亭 丁东亮 +2 位作者 刘鹏 苏红新 YAO X.Steve 《Optoelectronics Letters》 EI 2016年第6期433-436,共4页
We propose and demonstrate a novel single-longitudinal-mode(SLM) erbium-doped fiber laser(EDFL) capable of operating at fixed-wavelength lasing mode with a tunable range more than 54 nm, an ultra-narrow linewidth of 4... We propose and demonstrate a novel single-longitudinal-mode(SLM) erbium-doped fiber laser(EDFL) capable of operating at fixed-wavelength lasing mode with a tunable range more than 54 nm, an ultra-narrow linewidth of 473 Hz and an ultra-high optical signal-to-noise ratio(OSNR) more than 72 dB, or operating at wavelength-swept mode with tunable sweep rate of 10—200 Hz and a sweep range more than 50 nm. The excellent features mainly benefit from a triple-ring subring cavity constructed by three optical couplers nested one another and a fiber Fabry-Pérot tunable filter which can be driven by a constant voltage or a periodic sweep voltage for fixed or wavelength-swept operation, respectively. The proposed EDFL has potential applications in high-resolution spectroscopy and fiber optic sensing. 展开更多
关键词 tunable OSNR narrow lasing longitudinal triple capable Fabry sweep coupler
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