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Real-Time 3D Scene Perception in Dynamic Urban Environments via Street Detection Gaussians
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作者 yu du Runwei Guan +4 位作者 Ho-Pun Lam Jeremy Smith yutao yue KaLok Man Yan Li 《Computers, Materials & Continua》 2026年第4期1384-1402,共19页
As a cornerstone for applications such as autonomous driving,3D urban perception is a burgeoning field of study.Enhancing the performance and robustness of these perception systems is crucial for ensuring the safety o... As a cornerstone for applications such as autonomous driving,3D urban perception is a burgeoning field of study.Enhancing the performance and robustness of these perception systems is crucial for ensuring the safety of next-generation autonomous vehicles.In this work,we introduce a novel neural scene representation called Street Detection Gaussians(SDGs),which redefines urban 3D perception through an integrated architecture unifying reconstruction and detection.At its core lies the dynamic Gaussian representation,where time-conditioned parameterization enables simultaneous modeling of static environments and dynamic objects through physically constrained Gaussian evolution.The framework’s radar-enhanced perception module learns cross-modal correlations between sparse radardata anddense visual features,resulting ina22%reduction inocclusionerrors compared tovisiononly systems.A breakthrough differentiable rendering pipeline back-propagates semantic detection losses throughout the entire 3D reconstruction process,enabling the optimization of both geometric and semantic fidelity.Evaluated on the Waymo Open Dataset and the KITTI Dataset,the system achieves real-time performance(135 Frames Per Second(FPS)),photorealistic quality(Peak Signal-to-Noise Ratio(PSNR)34.9 dB),and state-of-the-art detection accuracy(78.1%Mean Average Precision(mAP)),demonstrating a 3.8×end-to-end improvement over existing hybrid approaches while enabling seamless integration with autonomous driving stacks. 展开更多
关键词 Radar-vision fusion differentiable rendering autonomous driving perception 3D reconstruction occlusion robustness
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Dissecting the Neural Circuitry for Pain Modulation and Chronic Pain:Insights from Optogenetics 被引量:5
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作者 Fang Guo yu du +3 位作者 Feng-Hui Qu Shi-Da Lin Zhong Chen Shi-Hong Zhang 《Neuroscience Bulletin》 SCIE CAS CSCD 2022年第4期440-452,共13页
Pain is an unpleasant sensory and emotional experience associated with,or resembling that associated with,actual or potential tissue damage.The processing of pain involves complicated modulation at the levels of the p... Pain is an unpleasant sensory and emotional experience associated with,or resembling that associated with,actual or potential tissue damage.The processing of pain involves complicated modulation at the levels of the periphery,spinal cord,and brain.The pathogenesis of chronic pain is still not fully understood,which makes the clinical treatment challenging.Optogenetics,which combines optical and genetic technologies,can precisely intervene in the activity of specific groups of neurons and elements of the related circuits.Taking advantage of optogenetics,researchers have achieved a body of new findings that shed light on the cellular and circuit mechanisms of pain transmission,pain modulation,and chronic pain both in the periphery and the central nervous system.In this review,we summarize recent findings in pain research using optogenetic approaches and discuss their significance in understanding the pathogenesis of chronic pain. 展开更多
关键词 OPTOGENETICS Pain transmission Pain modulation Chronic pain Neural circu
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Cs-Induced Phase Transformation of Vanadium Oxide for High-Performance Zinc-Ion Batteries 被引量:4
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作者 Gan Qu Kai Guo +4 位作者 Weijie Chen yu du Ye Wang Bingbing Tian Jianan Zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期265-272,共8页
Rechargeable aqueous zinc-ion batteries are promising candidate for gridscale energy storage.However,the development of zinc-ion batteries has been plagued by the lack of cathode materials with high specific capacity ... Rechargeable aqueous zinc-ion batteries are promising candidate for gridscale energy storage.However,the development of zinc-ion batteries has been plagued by the lack of cathode materials with high specific capacity and superior lifespan.Herein,hexagonal Cs_(0.3)V_(2)O_(5)cathode is fabricated and investigated in zinc-ion batteries.Compared with the traditional vanadium oxides,the introduction of Cs changes the periodic atomic arrangements,which not only stabilizes the open framework structure but also facilitates the Zn^(2+)diffusion with a lower migration energy barrier.Consequently,high specific capacity of 543.8 mA h g^(-1)at 0.1 A g^(-1)is achieved,which surpasses most of reported cathode materials in zinc-ion batteries.The excellent cycle life is achieved over 1000 cycles with about 87.8%capacity retention at 2 A g^(-1).Furthermore,the morphological evolution and energy storage mechanisms are also revealed via a series of techniques.This work opens up a phase engineering strategy to fabricate the hexagonal vanadium oxide and elucidate the application of phase-dependent cathodes in zinc-ion batteries. 展开更多
关键词 cathode materials phase engineering vanadium oxide zinc-ion batteries
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Formation of Low-Level Jets over Southern China in the Mei-yu Season 被引量:3
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作者 Xuanyu LIU Guixing CHEN +1 位作者 Sijia ZHANG yu du 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第10期1731-1748,共18页
This study examines the diversity of low-level jet(LLJ)formation and related physical processes over southern China.A total of 171 LLJ formation events with enhanced daily southwesterlies and early-morning maximum win... This study examines the diversity of low-level jet(LLJ)formation and related physical processes over southern China.A total of 171 LLJ formation events with enhanced daily southwesterlies and early-morning maximum wind speeds were observed during the mei-yu seasons of 1989–2018.The LLJs can be further categorized into four types based on the increases in the daily mean and diurnal amplitude of the low-level winds.Analysis of the synoptic-scale disturbances shows that the two types of LLJ formation(Q1 and Q4),which feature large increases of daily southerly wind components,are mainly induced by west-east dipole patterns of pressure change,in association with the enhanced southwest vortex and/or the western Pacific subtropical high(WPSH).In contrast,the other two types(Q2 and Q3),which feature relatively large increases in their daily westerly components,are related to a northwest-southeast dipole pattern of pressure change due to the mid-latitude trough and the WPSH.We further analyze the considerable variations in the diurnal thermal forcing among the LLJ formation events.The strong(weak)daytime heating of solar radiation leads to relatively large(small)increases in the diurnal amplitude of low-level winds in Q1 and Q2(Q3 and Q4)types.Therefore,different combinations of synopticscale disturbances and diurnal thermal forcings are found to account for the diversity in LLJ formation and associated differences in downstream rainfall patterns.These results help to improve our understanding and prediction of the formation of LLJs. 展开更多
关键词 low-level jets formation processes diurnal variations synoptic-scale disturbances
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Reexamination of Sexual Dimorphism and Female Reproduction in the Many-Lined Sun Skink Eutropis multifasciata from China 被引量:2
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作者 yu du Yanyan SUN +1 位作者 Chixian LIN Xiang JI 《Asian Herpetological Research》 SCIE 2012年第4期265-272,共8页
We reexamined sexual dimorphism and female reproduction in the Many-Lined Sun Skink Eutropis multifasciata from Hainan,China. Our data confirm that adults are sexually dimorphic in body size and shape,with males being... We reexamined sexual dimorphism and female reproduction in the Many-Lined Sun Skink Eutropis multifasciata from Hainan,China. Our data confirm that adults are sexually dimorphic in body size and shape,with males being the larger sex and larger in head size but shorter in abdomen length than females of the same snoutvent length(SVL). The rate at which head width increased with SVL was greater in males as opposed to the previous conclusion that the rate does not differ between the sexes. Maternal size was the main determinant of reproductive investment,with larger females generally producing more,as well as larger,offspring. Females produced up to nine offspring per litter as opposed to the previously reported 2–7. Most females gave birth between March and August,a time period approximately four months longer than that(May–June) reported previously. Females with a higher fecundity tended to produce smaller offspring as opposed to the previous conclusion that females do not tradeoff offspring size against number. Litter size,neonate mass and litter mass remained remarkably constant among years,and litter mass was more tightly related to female body size than litter size or neonate mass. Smaller females could produce relatively heavier litters without a concomitant reduction in postpartum body condition. 展开更多
关键词 SCINCIDAE Eutropis multifasciata sexual dimorphism litter size neonate size reproductive output offspring size-number trade-off
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Sexual Dimorphism, Female Reproductive Characteristics and Egg Incubation in an Oviparous Forest Skink(Sphenomorphus incognitus) from South China 被引量:2
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作者 Li MA Jianchi PEI +3 位作者 Cuntong ZHOU yu du Xiang JI Wen SHEN 《Asian Herpetological Research》 SCIE CSCD 2018年第2期119-128,共10页
We studied sexual dimorphism and female reproduction in an oviparous forest skink (Sphenomorphus incognitus) from South China. We incubated eggs under five thermal regimes (22, 25, 28, 25 ± 3 and 27± 5℃... We studied sexual dimorphism and female reproduction in an oviparous forest skink (Sphenomorphus incognitus) from South China. We incubated eggs under five thermal regimes (22, 25, 28, 25 ± 3 and 27± 5℃) to examine the effects of constant versus fluctuating temperatures on incubation length and hatchling morphology. In our sample the largest male and female were 110 mm and 108 mm snout-vent length (SVL), respectively. Adult males and females did not differ in mean SVL; adult males were larger in head size (both length and width), longer in fore- and hind-limb lengths and shorter in abdomen length than females of the same SVL. Accordingly, we conclude that S. incognitus is a sexually monomorphic species in terms of SVL but shows sexual dimorphism in head size, abdomen length and appendage length. Females laid a single clutch of 3-10 eggs per breeding season from early May to mid- August, with larger females generally laying more (but not always larger) eggs per clutch than did smaller ones. Embryonic stages at laying ranged from Dufaure and Hubert's (1961) stage 31 to 32, with a mean stage of 31.3. The positive relationship between clutch mass and female SVL was not significant. The offspring size-number trade-off does not exist in S, incognitus, as revealed by the fact that egg mass was independent of relative fecundity. Incubation length decreased as temperature increased, and stable temperatures resulted in delayed hatching. Hatchlings incubated under the five thermal regimes did not differ from each other in any examined trait, suggesting that S. incognitus is among oviparous reptilian species where incubation temperature has no role in modifying hatchling morphology as long as eggs are not exposed to extreme temperatures for prolonged periods of time. 展开更多
关键词 EGG hatchling morphology incubation length reproduction SCINCIDAE sexual dimorphism
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Cluster analysis of polymers using laser-induced breakdown spectroscopy with K-means 被引量:4
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作者 Yangmin GUO yun TANG +4 位作者 yu du Shisong TANG Lianbo GUO Xiangyou LI Yongfeng LU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第6期99-103,共5页
Laser-induced breakdown spectroscopy(LIBS) combined with K-means algorithm was employed to automatically differentiate industrial polymers under atmospheric conditions.The unsupervised learning algorithm K-means wer... Laser-induced breakdown spectroscopy(LIBS) combined with K-means algorithm was employed to automatically differentiate industrial polymers under atmospheric conditions.The unsupervised learning algorithm K-means were utilized for the clustering of LIBS dataset measured from twenty kinds of industrial polymers.To prevent the interference from metallic elements,three atomic emission lines(C I 247.86 nm,H I 656.3 nm,and O I 777.3 nm) and one molecular line C–N(0,0) 388.3 nm were used.The cluster analysis results were obtained through an iterative process.The Davies–Bouldin index was employed to determine the initial number of clusters.The average relative standard deviation values of characteristic spectral lines were used as the iterative criterion.With the proposed approach,the classification accuracy for twenty kinds of industrial polymers achieved 99.6%.The results demonstrated that this approach has great potential for industrial polymers recycling by LIBS. 展开更多
关键词 laser-induced breakdown spectroscopy polymers K-means
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Evaluation of Advanced Gastric Carcinoma with Monoenergetic Spectrum Curve of Dual-source Dual-energy Computed Tomography 被引量:1
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作者 Li-mei Pei Gao-feng Shi +2 位作者 Run-ze Wu Ru-xun Li yu du 《Chinese Medical Sciences Journal》 CAS CSCD 2013年第1期64-64,共1页
GASTRIC cancer is one of the most frequently diagnosed cancers and leading causes of cancer-related deaths.Computed tomography(CT) is routinely used to observe the tumor location,size,invasion,and metastasis,which are... GASTRIC cancer is one of the most frequently diagnosed cancers and leading causes of cancer-related deaths.Computed tomography(CT) is routinely used to observe the tumor location,size,invasion,and metastasis,which are necessary for tumor staging and therefore treatment planning.With the recently introduced dual-source dual-energy CT(DECT), 展开更多
关键词 断层扫描 光谱曲线 胃癌 双源 电脑 DECT 能电 评价
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Sexual Dimorphism,Female Reproductive Characteristics and Embryonic Thermosensitivity in the Tonkin Forest Skink(Sphenomorphus tonkinensis)from Hainan,South China 被引量:1
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作者 yu du Chixian LIN +2 位作者 Xiaming ZHU yuntao YAO Xiang JI 《Asian Herpetological Research》 SCIE CSCD 2023年第4期271-279,共9页
We collected 75 adult Tonkin forest skinks(Sphenomorphus tonkinensis) from Hainan, South China and incubated eggs at four constant temperatures ranging from 22 ℃ to 28 ℃ to study sexual dimorphism, female reproducti... We collected 75 adult Tonkin forest skinks(Sphenomorphus tonkinensis) from Hainan, South China and incubated eggs at four constant temperatures ranging from 22 ℃ to 28 ℃ to study sexual dimorphism, female reproductive characteristics and embryonic thermosensitivity. The largest male was 53.4 mm snout-vent length(SVL), and the largest female was 54.3 mm SVL. The mean SVL was slightly greater in adult females(49.9 mm) than in adult males(48.8 mm), but the difference was not significant.Head length, head width, fore-limb length and hindlimb length were longer in adult males and abdomen length was longer in adult females after accounting for SVL. Accordingly, we conclude that S. tonkinensis is basically a sexually size-monomorphic species with sexual dimorphism in head size, abdomen(trunk)length and limb size. Females laid up to two clutches of 1–4 eggs each per egg-laying season from February to May. Egg mass, clutch size and clutch mass were independent of female SVL. Embryonic stages at laying varied from Dufaure and Hubert’s stage 30 to 31. With female SVL held constant, the negative correlation between egg mass and clutch size was not significant, suggesting that the offspring(egg) sizenumber trade-off between is not evident or eggs are well optimized for size in S. tonkinensis. None of the eggs at 28 ℃ hatched;hatching success was lower at 22 ℃ than at 24 ℃ or 26 ℃. The mean incubation length was 52.9 d at 22 ℃, 40.4 d at 24 ℃ and 33.6 d at 26 ℃. Hatchlings from eggs incubated at 22 ℃,24 ℃ and 26 ℃ did not differ morphologically at hatching, suggesting that temperatures within this range do not differentially affect hatchling morphology in S. tonkinensis. 展开更多
关键词 egg hatching success hatchling morphology incubation length reproduction SCINCIDAE sexual dimorphism
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Multi-Omics-Guided Discovery of Omicsynins Produced by Streptomyces sp.1647:Pseudo-Tetrapeptides Active Against Influenza A Viruses and Coronavirus HCoV-229E 被引量:1
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作者 Hongmin Sun Xingxing Li +14 位作者 Minghua Chen Ming Zhong Yihua Li Kun Wang yu du Xin Zhen Rongmei Gao Yexiang Wu yuanyuan Shi Liyan yu Yongsheng Che yuhuan Li Jian-Dong Jiang Bin Hong Shuyi Si 《Engineering》 SCIE EI CAS 2022年第9期176-186,共11页
Many microorganisms have mechanisms that protect cells against attack from viruses.The fermentation components of Streptomyces sp.1647 exhibit potent anti-influenza A virus(IAV)activity.This strain was isolated from s... Many microorganisms have mechanisms that protect cells against attack from viruses.The fermentation components of Streptomyces sp.1647 exhibit potent anti-influenza A virus(IAV)activity.This strain was isolated from soil in southern China in the 1970s,but the chemical nature of its antiviral substance(s)has remained unknown until now.We used an integrated multi-omics strategy to identify the antiviral agents from this streptomycete.The antibiotics and Secondary Metabolite Analysis Shell(antiSMASH)analysis of its genome sequence revealed 38 biosynthetic gene clusters(BGCs)for secondary metabolites,and the target BGCs possibly responsible for the production of antiviral components were narrowed down to three BGCs by bioactivity-guided comparative transcriptomics analysis.Through bioinformatics analysis and genetic manipulation of the regulators and a biosynthetic gene,cluster 36 was identified as the BGC responsible for the biosynthesis of the antiviral compounds.Bioactivity-based molecular networking analysis of mass spectrometric data from different recombinant strains illustrated that the antiviral compounds were a class of structural analogues.Finally,18 pseudo-tetrapeptides with an internal ureido linkage,omicsynins A1–A6,B1–B6,and C1–C6,were identified and/or isolated from fermentation broth.Among them,11 compounds(omicsynins A1,A2,A6,B1–B3,B5,B6,C1,C2,and C6)are new compounds.Omicsynins B1–B4 exhibited potent antiviral activity against IAV with the 50%inhibitory concentration(IC_(50))of approximately 1μmol·L^(-1)and a selectivity index(SI)ranging from 100 to 300.Omicsynins B1–B4 also showed significant antiviral activity against human coronavirus HCoV-229E.By integrating multi-omics data,we discovered a number of novel antiviral pseudo-tetrapeptides produced by Streptomyces sp.1647,indicating that the secondary metabolites of microorganisms are a valuable source of novel antivirals. 展开更多
关键词 Multi-omics Anti-influenza A virus Anti-coronavirus Streptomyces sp.1647 Pseudo-tetrapeptides
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Reproducibility study of intravoxel incoherent motion and apparent diffusion coefficient parameters in normal pancreas 被引量:1
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作者 Xiang Liu Yi-Feng Wang +6 位作者 Xiao-Hui Qi Zhi-Lei Zhang Jiang-Yang Pan Xue-Li Fan yu du Ying-Min Zhai Qi Wang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第7期2031-2039,共9页
BACKGROUND The consistency of pancreatic apparent diffusion coefficient(ADC)values and intravoxel incoherent motion(IVIM)parameter values across different magnetic resonance imaging(MRI)devices significantly impacts t... BACKGROUND The consistency of pancreatic apparent diffusion coefficient(ADC)values and intravoxel incoherent motion(IVIM)parameter values across different magnetic resonance imaging(MRI)devices significantly impacts the patient’s diagnosis and treatment.AIM To explore consistency in image quality,ADC values,and IVIM parameter values among different MRI devices in pancreatic examinations.METHODS This retrospective study was approved by the local ethics committee,and informed consent was obtained from all participants.In total,22 healthy volunteers(10 males and 12 females)aged 24-61 years(mean,28.9±2.3 years)underwent pancreatic diffusion-weighted imaging using 3.0T MRI equipment from three vendors.Two independent observers subjectively scored image quality and measured the pancreas’s overall ADC values and signal-to-noise ratios(SNRs).Subsequently,regions of interest(ROIs)were delineated for the IVIM parameters(true diffusion coefficient,pseudo-diffusion coefficient,and perfusion fraction)using post-processing software.These ROIs were on the head,body,and tail of the pancrease.The subjective image ratings were assessed using the kappa consistency test.Intraclass correlation coefficients(ICCs)and mixed linear models were used to evaluate each device’s quantitative parameter values.Finally,a pairwise analysis of IVIM parameter values across each device was performed using Bland-Altman plots.RESULTS The Kappa value for the subjective ratings of the different observers was 0.776(P<0.05).The ICC values for interobserver and intra-observer agreements for the quantitative parameters were 0.803[95% confidence interval(CI):0.684-0.880]and 0.883(95%CI:0.760-0.945),respectively(P<0.05).The ICCs for the SNR between different devices was comparable(P>0.05),and the ICCs for the ADC values from different devices were 0.870,0.707,and 0.808,respectively(P<0.05).Notably,only a few statistically significant inter-device agreements were observed for different IVIM parameters,and among those,the ICC values were generally low.The mixed linear model results indicated differences(P<0.05)in the f-value for the pancreas head,D-value for the pancreas body,and D-value for the pancreas tail obtained using different MRI machines.The Bland-Altman plots showed significant variability at some data points.CONCLUSION ADC values are consistent among different devices,but the IVIM parameters’repeatability is moderate.Therefore,the variability in the IVIM parameter values may be associated with using different MRI machines.Thus,caution should be exercised when using IVIM parameter values to assess the pancreas. 展开更多
关键词 Intravoxel incoherent motion PANCREAS Image quality Consistency test
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Uncalibrated Workpiece Positioning Method for Peg-in-hole Assembly Using an Industrial Robot 被引量:1
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作者 Ming CONG Fukang ZHU +1 位作者 Dong LIU yu du 《Instrumentation》 2019年第4期26-36,共11页
This paper proposes an uncalibrated workpiece positioning method for peg-in-hole assembly of a device using an industrial robot.Depth images are used to identify and locate the workpieces when a peg-in-hole assembly t... This paper proposes an uncalibrated workpiece positioning method for peg-in-hole assembly of a device using an industrial robot.Depth images are used to identify and locate the workpieces when a peg-in-hole assembly task is carried out by an industrial robot in a flexible production system.First,the depth image is thresholded according to the depth data of the workpiece surface so as to filter out the background interference.Second,a series of image processing and the feature recognition algorithms are executed to extract the outer contour features and locate the center point position.This image information,fed by the vision system,will drive the robot to achieve the positioning,approximately.Finally,the Hough circle detection algorithm is used to extract the features and the relevant parameters of the circular hole where the assembly would be done,on the color image,for accurate positioning.The experimental result shows that the positioning accuracy of this method is between 0.6-1.2 mm,in the used experimental system.The entire positioning process need not require complicated calibration,and the method is highly flexible.It is suitable for the automatic assembly tasks with multi-specification or in small batches,in a flexible production system. 展开更多
关键词 Uncalibrated Workpiece Positioning Industrial Robot Visual Positioning Peg-in-hole Assembly
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The functional significance of residual yolk in lizards
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作者 Kun Guo Cai-Feng Wang +3 位作者 yu du Yan-Fu Qu Florentino Brana Xiang Ji 《Current Zoology》 SCIE CAS CSCD 2023年第2期192-199,共8页
Residual yolk is assumed to be an important source of energy and nutrients during early life in nonmammalian amniotes.Available data show that the mean size of residual yolk is far smaller in lizards than in turtles,s... Residual yolk is assumed to be an important source of energy and nutrients during early life in nonmammalian amniotes.Available data show that the mean size of residual yolk is far smaller in lizards than in turtles,snakes,crocodiles,and birds,raising a question of whether residual yolk is of functional significance in lizards.Here,we compared data from 26 lizard species with those from other nonmammalian amniotes to test the hypothesis that residual yolk is functionally less significant in species producing more fully developed offspring.In our sample,species mean offspring water contents ranged from 73%to 84%of body wet mass;species mean proportions of carcass dry mass,fat-body dry mass,and residual yolk dry mass to offspring dry mass ranged from 84%to 99%,0%to 5.0%,and 0%to 14.4%,respectively.Lizards are,on average,more fully developed at hatching or birth than snakes,as revealed by the fact that the mean proportion of carcass dry mass to body dry mass and offspring water contents were both higher in lizards than in snakes.We conclude that the functional significance of residual yolk during early life is generally less evident in lizards.Even in the lizards where residual yolk is of potential functional significance,this portion of yolk contributes little,if any,to postembryonic growth.Future work could usefully collect data across a wider spectrum of reptile taxa to establish a precocial-altricial continuum and test the hypothesis that species with a smaller amount of residual yolk are closer to the precocial end of the continuum. 展开更多
关键词 CARCASS fatbody LIZARDS OFFSPRING postembryonicgrowth residual yolk
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Sexual Dimorphism and Female Reproductive Characteristics in the Hainan Water Skink(Tropidophorus hainanus)from Hainan,South China
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作者 yu du Xiaming ZHU +2 位作者 Chixian LIN yuntao YAO Xiang JI 《Asian Herpetological Research》 SCIE CSCD 2024年第1期49-58,共10页
We studied sexual dimorphism in body size and shape and female reproductive characteristics in the Hainan Water Skink(Tropidophorus hainanus)from Hainan,South China.In our sample the largest female and male were 61.1 ... We studied sexual dimorphism in body size and shape and female reproductive characteristics in the Hainan Water Skink(Tropidophorus hainanus)from Hainan,South China.In our sample the largest female and male were 61.1 and 55.2 mm snout-vent length(SVL),respectively.The mean SVL was larger in adult females(52.0 mm)than in adult males(48.3 mm).Juveniles were sexually dimorphic in head length but not in other examined morphological variables.Adult males were longer in head length and shorter in abdomen length and fore-limb length than adult females of the same SVL.Ontogenetic shifts in sexual dimorphism in body shape were evident,as revealed by the fact that morphological differences between the sexes were more pronounced in adults than in juveniles.Females produced a single litter of 3–6 offspring per season from early August to early September.Litter size,litter mass and offspring(neonate)mass were positively related to female SVL.Neonate mass was independent of relative fecundity.From the above findings we draw three main conclusions.First,females are the larger sex in T.hainanus,and sexual dimorphism in body shape is more pronounced in adults than in juveniles.Second,larger female T.hainanus produce more and larger offspring and thus heavier litters than smaller ones.Third,the offspring size-number trade-off does is not evident in T.hainanus. 展开更多
关键词 FECUNDITY morphology offspring size-number trade-off REPRODUCTION SCINCIDAE sexual dimorphism
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Body Size and Reproductive Tactics in Varanid lizards
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作者 yu du Longhui LIN +2 位作者 yuntao YAO Chixian LIN Xiang JI 《Asian Herpetological Research》 SCIE 2014年第4期263-270,共8页
Body size and female reproduction in the water adult females larger than 500 mm SVL and 32 adult males Ledong, Hainan under permit to our laboratory in Hainan monitor lizard (Varanus salvator) were studied. Forty-tw... Body size and female reproduction in the water adult females larger than 500 mm SVL and 32 adult males Ledong, Hainan under permit to our laboratory in Hainan monitor lizard (Varanus salvator) were studied. Forty-two larger than 400 mm SVL were donated by local people in in 2013 and 2014. The largest male and female measured 745 and 755 mm SVL, respectively. The mean SVL was greater in adult females than in adult males. Males had larger heads (head width) than females of the same SVL. The smallest reproductive female in our sample was 565 mm SVL. Females produced a single clutch of 17.1 (10-23) pliable-shelled eggs per breeding season stretching from mid-June and mid-September. Clutch size and clutch mass were all positively related to female SVL. However, there was no significant linear relationship between egg mass and female SVL. Larger females generally produced more eggs, and thus heavier clutches than did smaller ones. There was no significant linear relationship between relative clutch mass and female SVL. Phylogenetic generalized least squares (PGLS) analysis, accounting for phylogenetic relationships, showed that clutch size was positively correlated with mean maternal SVL in varanid lizards. PGLS analysis showed that phylogenetic relationships did not affect clutch (or/and egg) mass and the SVL although there were significant linear relationship between clutch (or/and egg) mass and mean maternal SVL. Therefore, we could draw some general conclusions about the body size and reproductive tactics in varanid lizards that larger females generally produced more eggs, larger eggs and thus heavier clutches than did smaller ones. 展开更多
关键词 body size female reproduction monitor lizard VARANIDAE
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Discussion on the Cultivation of the Core Quality of Middle School Students’ Physical Education in Primary School Physical Education Teaching
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作者 Xin Li Bingyao Niu yu du 《Journal of Contemporary Educational Research》 2023年第7期30-34,共5页
In the context of quality education,a wider exploration of physical education has been carried out,but at the same time higher requirements have been put forward for school sports courses.It is essential to pay attent... In the context of quality education,a wider exploration of physical education has been carried out,but at the same time higher requirements have been put forward for school sports courses.It is essential to pay attention to the teaching and training of physical knowledge and skills in physical education training as well as cultivate the core physical literacy of primary school students.The core quality of physical education is the main part of the basic quality of primary and middle school students,which is of great significance to their learning and development.This article will explore the training methods of primary and middle school students’basic quality in school physical education courses for reference. 展开更多
关键词 Physical education Core literacy Training strategies Curriculum standards
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青藏高原东缘隧道建设对表层土壤团聚体及其有机碳稳定性的影响 被引量:1
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作者 于杜 张原 +7 位作者 陈雨卓 向金成 王率 陈果 曹龙熹 李凛 裴向军 唐晓鹿 《环境工程技术学报》 北大核心 2025年第4期1409-1421,共13页
土壤团聚体有机碳稳定性是评价土壤固碳能力和养分保持能力以及土壤对外界环境变化响应的重要指标,为阐明隧道工程建设对土壤团聚体及其有机碳的影响特征,在铁路工程影响区沿3240、3420、3600 m三个海拔梯度分别设置3个固定监测样地(TC1... 土壤团聚体有机碳稳定性是评价土壤固碳能力和养分保持能力以及土壤对外界环境变化响应的重要指标,为阐明隧道工程建设对土壤团聚体及其有机碳的影响特征,在铁路工程影响区沿3240、3420、3600 m三个海拔梯度分别设置3个固定监测样地(TC1、TC2、TC3),以非影响区为对照(CK1、CK2、CK3),基于方差分析,从土壤理化性质、团聚体、团聚体有机碳等角度探究隧道建设对土壤团聚体及其有机碳稳定性的影响。结果表明,TC区域的含水率、孔隙度等物理性质以及团聚体质量和稳定性受到隧道建设影响显著(P<0.05)。TC与CK中,pH、氮、磷等化学性质以及团聚体总有机碳、易氧化有机碳、可溶性有机碳、惰性有机碳含量不受隧道建设影响(P>0.05),在海拔和土层影响下则差异显著(P<0.05)。三因素方差分析结合相关性分析表明隧道建设通过直接破坏土壤结构,降低土壤团聚体稳定性,对维持团聚体有机碳稳定性的土壤团聚体物理保护机制产生显著影响;研究区凋落物生物量和酶活、微生物量碳以及团聚体有机碳组分无显著变化,表明隧道建设对维持团聚体有机碳稳定性的植物以及微生物学调控机制无显著影响,即隧道建设未对土壤团聚体有机碳稳定性造成影响。 展开更多
关键词 隧道建设 青藏高原 土壤团聚体 有机碳稳定性
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Efficient fabrication of fabric-based Janus interfacial evaporator via melt centrifugal spinning for simultaneous solar evaporation,pollutant degradation,antibacterial action,and thermoelectric output 被引量:1
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作者 Yingying Chen Rong Zhou +5 位作者 Hao Wang Xiaowei Ning yu du Heng Xie Ting Wu Jinping Qu 《Journal of Energy Chemistry》 2025年第6期385-394,I0009,共11页
Fiber fabrics have been wildly utilized for solar interracial evaporators to address freshwater scarcity.However,the complex and expensive manufacturing processes remain limited to their scalable development.Herein,a ... Fiber fabrics have been wildly utilized for solar interracial evaporators to address freshwater scarcity.However,the complex and expensive manufacturing processes remain limited to their scalable development.Herein,a fabric-based Janus interracial evaporator is efficiently fabricated on a large scale by integrating an extremely innovative self-designed melt-centrifugal spinning technology with spray coating technology.The prepared fabric-based Janus interfacial evaporator has differential hydrophilicity,uneven surfaces,and channels that allow moisture escape.Benefiting from the excellent photothermai conversion of graphene oxide and the charge transfer actions of titanium dioxide,such a multifunction evaporator can reach a high evaporation rate of 1.72 kg m^(-2)h^(-1)under 1 sun irradiation,a superior antibacterial rate of 99%,excellent photocatalytic degradation,and effective thermoelectric ability simultaneously.Moreover,it also shows fantastic performance in salt resistance,recyclable evaporation,and real desalination,This work demonstrates a high-efficiency,cost-effective,multifunctional,and scalable strategy for high-performance fiber fabrics solar interfacial evaporation. 展开更多
关键词 Melt-centrifugal spinning Solar interfacial evaporation Thermoelectric ANTIBACTERIAL Photocatalytic degradation
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Bioinspired Ultrasensitive Flexible Strain Sensors for Real‑Time Wireless Detection of Liquid Leakage
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作者 Weilong Zhou yu du +6 位作者 Yingying Chen Congyuan Zhang Xiaowei Ning Heng Xie Ting Wu Jinlian Hu Jinping Qu 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期310-327,共18页
Liquid leakage of pipeline networks not only results in considerableresource wastage but also leads to environmental pollution and ecological imbalance.In response to this global issue, a bioinspired superhydrophobic ... Liquid leakage of pipeline networks not only results in considerableresource wastage but also leads to environmental pollution and ecological imbalance.In response to this global issue, a bioinspired superhydrophobic thermoplastic polyurethane/carbon nanotubes/graphene nanosheets flexible strain sensor (TCGS) hasbeen developed using a combination of micro-extrusion compression molding andsurface modification for real-time wireless detection of liquid leakage. The TCGSutilizes the synergistic effects of Archimedean spiral crack arrays and micropores,which are inspired by the remarkable sensory capabilities of scorpions. This designachieves a sensitivity of 218.13 at a strain of 2%, which is an increase of 4300%. Additionally, it demonstrates exceptional durability bywithstanding over 5000 usage cycles. The robust superhydrophobicity of the TCGS significantly enhances sensitivity and stability indetecting small-scale liquid leakage, enabling precise monitoring of liquid leakage across a wide range of sizes, velocities, and compositionswhile issuing prompt alerts. This provides critical early warnings for both industrial pipelines and potential liquid leakage scenariosin everyday life. The development and utilization of bioinspired ultrasensitive flexible strain sensors offer an innovative and effectivesolution for the early wireless detection of liquid leakage. 展开更多
关键词 Thermoplastic polyurethane BIOINSPIRED Cracks Liquid leakage Flexible strain sensor
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富血小板血浆复合骨骼肌干细胞可促进骨修复 被引量:6
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作者 殷诺 薛锋 +6 位作者 肖海军 丁亮 袁君杰 潘明芒 喻都 鞠金勇 朱龙章 《中国组织工程研究》 CAS 北大核心 2019年第17期2678-2683,共6页
背景:富血小板血浆含有的血小板颗粒富含多种活性因子,将其作为促进干细胞分化的细胞因子进行组织工程骨修复具有一定的优势。目的:探讨富血小板血浆复合骨骼肌干细胞促进兔肱骨近端骨缺损修复的效果。方法:制备兔富血小板血浆,提取兔... 背景:富血小板血浆含有的血小板颗粒富含多种活性因子,将其作为促进干细胞分化的细胞因子进行组织工程骨修复具有一定的优势。目的:探讨富血小板血浆复合骨骼肌干细胞促进兔肱骨近端骨缺损修复的效果。方法:制备兔富血小板血浆,提取兔比目鱼肌组织中的骨骼肌干细胞。将28只新西兰白兔随机分为4组,自然愈合组、骨骼肌干细胞组,富血小板血浆组、复合材料组,每组7只,均制备肱骨近端骨缺损模型,后3组造模后骨缺损处分别植入同种异体骨骼肌干细胞、自体富血小板血浆、富血小板血浆复合骨骼肌干细胞。术后进行CT检查及组织学观察骨愈合情况。结果与结论:①术后4周起复合材料组影像学上成骨速率明显高于其他3组(P <0.05);骨骼肌干细胞组、富血小板血浆组成骨速率无明显差异(P> 0.05),均明显高于自然愈合组(P <0.05);②复合材料组骨缺损处组织学评分最高,骨骼肌干细胞组和富血小板血浆组组织学评分无明显差异,自然愈合组组织学评分最低;③结果表明,富血小板血浆和骨骼肌干细胞都具有促进骨修复的作用,而二者结合能更好地修复骨缺损。 展开更多
关键词 富血小板血浆 骨骼肌干细胞 肱骨近端骨缺损 诱导成骨 骨修复 骨折愈合 成骨速度
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