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The validity of automatic methods for estimating maturation stage in young athletes:A comparison of the Maturo smartphone application and sport science expert evaluations
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作者 Ximing Shang Jorge Arede +1 位作者 Pedro Couto Nuno Leite 《Journal of Sport and Health Science》 2025年第4期32-39,共8页
Background: Biological maturation refers to the progressive process through which individuals transition toward an adult state during growth and development. To address the challenges posed by differences in biologica... Background: Biological maturation refers to the progressive process through which individuals transition toward an adult state during growth and development. To address the challenges posed by differences in biological maturity and the limitations of existing testing methods, particularly in adolescent sports contexts, there is a pressing need for a non-invasive method that is convenient, accurate, and broadly applicable to monitor the biological maturity of adolescent athletes comprehensively. In response to this need, a maturity assessment method based on the smartphone application Maturo has been developed. This study evaluates the accuracy and validity of the Maturo software, an automated tool for estimating biological age and related maturation metrics.Methods: A sample of 103 actively training teenage athletes aged 9-17 years. The sample included 76 males(age = 11.74 ± 1.55 years, mean ±SD) and 27 females(age = 13.95 ± 1.40 years), all without medical conditions that might impact growth or development.Results: Compared to traditional expert evaluations, the intraclass correlation coefficients(ICCs) and Pearson correlation coefficients demonstrated reliable positive correlations and significant agreement between the Maturo software and expert methods across multiple metrics, such as biological age(ICC = 0.965, R = 0.97), corrected biological age(ICC = 0.973, R = 0.99), predicted adult height(ICC = 0.991, R = 0.99), and percentage of adult height achieved(ICC = 0.955, R = 0.97). The Bland-Altman plots provided additional evidence of the validity of the Maturo software estimations, showing low systematic error in most measures. The linear regression analysis produced excellent adjusted R2values: 0.95for biological age and 0.99 for anticipated adult height. The Maturo approach demonstrated a high level of dependability in classifying teenagers into groups based on their maturity status and timing. The κ coefficients of 0.93 for maturity status and 0.82 for maturity timing indicate a nearly perfect agreement with the expert technique.Conclusion: While the Maturo software's non-invasive nature, cost-effectiveness, and ease of use could make it a potential tool for regular monitoring of growth and maturation in young athletes, its promising results in assessing maturation should be interpreted with caution due to limitations such as sample size and demographic constraints. Further longitude research with larger and more diverse populations is needed to validate these preliminary findings and strengthen the evidence for its broader applicability. 展开更多
关键词 maturation assessment Youth athletes Maturo software Biological maturation estimation ANTHROPOMETRY
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Genome-wide circular RNAs signatures involved in sexual maturation and its heterosis in chicken
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作者 Yuanmei Wang Jingwei Yuan +10 位作者 Yanyan Sun Aixin Ni Jinmeng Zhao Yunlei Li Panlin Wang Lei Shi Yunhe Zong Pingzhuang Ge Shixiong Bian Hui Ma Jilan Chen 《Journal of Integrative Agriculture》 2025年第2期697-711,共15页
Sexual maturation heterosis has been widely exploited in animal crossbreeding.However,the underlying mechanism has been rarely explored in chicken.In the present study,we performed the reciprocal crossing between Whit... Sexual maturation heterosis has been widely exploited in animal crossbreeding.However,the underlying mechanism has been rarely explored in chicken.In the present study,we performed the reciprocal crossing between White Leghorn and Beijing You chicken to evaluate the phenotypes related to sexual maturation,and profiled the ovary circRNAs of purebreds(WW,YY)and crossbreds(WY,YW)to elucidate the molecular mechanism underlying heterosis for sexual maturation.Pubic space and oviduct length exhibited positive heterosis,and age at first egg(AFE)exhibited negative heterosis in the crossbreds.We identified 3,025 known circRNAs and 624 putative circRNAs,which were mainly derived from the exons.Among these circRNAs,141 and 178circRNAs were specially expressed in WY and YW,respectively.There were 52.38 and 64.63%of total circRNAs in WY and YW exhibited non-additive expression pattern,respectively.GO enrichment and KEGG pathway analysis showed that the host genes of non-additive circRNAs were mainly involved in TGF-beta signaling pathway,oocyte development,ATPase activator activity,oocyte meiosis,progesterone-mediated oocyte maturation and GnRH signaling pathway.Weighted gene co-expression network analysis identified that 4 modules were significantly(P<0.05)correlated with oviduct length and pubic space.The host genes of non-additive circRNAs harbored in the 4 modules were associated with MAPK signaling pathway and Wnt signaling pathway.Furthermore,competing endogenous RNAs(ceRNA)network analysis characterized non-additive circRNAs gal-FGFR2_0005 and galMAPKAP1_0004 could interact with gga-miR-1612 and gga-miR-12235-5p to regulate CNOT6,COL8A1,and FHL2,which were essential for ovary development,indicating that the non-additive circRNAs involved in the formation of sexual maturation heterosis through regulating genes related to the reproductive and developmental process.The findings would provide a deeper understanding of the molecular mechanism underlying sexual maturation heterosis from a novel perspective. 展开更多
关键词 CHICKEN sexual maturation HETEROSIS OVARY circRNA
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Wnt2bb signaling promotes pharyngeal chondrogenic precursor proliferation and chondrocyte maturation by activating Yap expression in zebrafish
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作者 Xiaojuan Guo Liping Yang +4 位作者 Yujie Wang Mengna Yuan Wenqing Zhang Xinyu He Qiang Wang 《Journal of Genetics and Genomics》 2025年第2期220-230,共11页
Pharyngeal cartilage morphogenesis is crucial for the formation of craniofacial structures.Cranial neural crest cells are specified at the neural plate border,migrate to pharyngeal arches,and differentiate into pharyn... Pharyngeal cartilage morphogenesis is crucial for the formation of craniofacial structures.Cranial neural crest cells are specified at the neural plate border,migrate to pharyngeal arches,and differentiate into pharyngeal chondrocytes,which subsequently flatten,elongate,and stack like coins during maturation.Although the developmental processes prior to chondrocyte maturation have been extensively studied,their subsequent changes in morphology and organization remain largely elusive.Here,we show that wnt2bb is expressed in the pharyngeal ectoderm adjacent to the chondrogenic precursor cells in zebrafish.Inactivation of Wnt2bb leads to a reduction in nuclearβ-catenin,which impairs chondrogenic precursor proliferation and disrupts chondrocyte morphogenesis and organization,eventually causing a severe shrinkage of pharyngeal cartilages.Moreover,the decrease ofβ-catenin in wnt2bb^(-/-)mutants is accompanied by the reduction of Yap expression.Reactivation of Yap can restore the proliferation of chondrocyte progenitors as well as the proper size,shape,and stacking of pharyngeal chondrocytes.Our findings suggest that Wnt/β-catenin signaling promotes Yap expression to regulate pharyngeal cartilage formation in zebrafish. 展开更多
关键词 Wnt/β-catenin signaling YAP Wnt2bb Chondrocyte maturation Pharyngeal cartilage ZEBRAFISH
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ABA-activated subclassⅢSnRK2s control kernel maturation in maize
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作者 Yayun Wang Tiandan Long +8 位作者 Aying Qin Qiang Liao Hao Wang Junjie Zhang Hanmei Liu Yinghong Liu Yufeng Hu Yubi Huang Yangping Li 《The Crop Journal》 2025年第3期777-791,共15页
Seed maturation is a critical development transition and it largely affects the final yield and quality of crops.Abscisic acid(ABA)-activated sucrose-non-fermentation kinase subfamily 2(SnRK2s)constitute a well-known ... Seed maturation is a critical development transition and it largely affects the final yield and quality of crops.Abscisic acid(ABA)-activated sucrose-non-fermentation kinase subfamily 2(SnRK2s)constitute a well-known regulatory network that modulate seed maturation in Arabidopsis;however,the underlying genetic and regulatory mechanisms in cereal crops remain largely unknown.Here,we found that ABA levels exhibited two distinct peaks during kernel development in maize,corresponding to the lag and maturation phase,respectively.Integrated transcriptome and proteome profiling of kernels treated with exogenous ABA at the pre-maturation stage suggested that the second peak of ABA acts as a trigger for kernel maturation program.Knockout of ZmSnRK2s demonstrated that subclassⅢZmSnRK2s are required for kernel maturation in maize,and the loss-of-function of subclassⅢZmSnRK2s showed a disruption in kernel dehydration and dormancy.We identified a conserved ABA–SnRK2–b ZIP signaling pathway mediating this process in maize.Additionally,ZmSnRK2.10 overexpression accelerates kernel dehydration during maturity,achieving reduced kernel moisture content(KMC)at physiological maturity(PM).Overall,our findings establish ABA-activated SnRK2s as central regulators of kernel maturation in maize and provide valuable genetic resources for breeding maize varieties with low moisture content at harvest. 展开更多
关键词 Seed maturation ABA SubclassⅢZmSnRK2s Maize kernel KMC
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Accelerating Hydrocarbon Maturation: The Role of Metals and Unconventional Resources in the Northeast Java Basin
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作者 Bagus Sapto Mulyatno Muh Sarkowi +4 位作者 Ordas Dewanto Asep Irawan Suharso Andy Setyo Wibowo Indra Mamad Gandidi 《Energy Engineering》 2025年第8期3099-3116,共18页
Rising global energy needs have intensified the search for unconventional hydrocarbon sources,especially in under-selected areas like the Northeast Java Basin.This region harbors promising unconventional hydrocarbon r... Rising global energy needs have intensified the search for unconventional hydrocarbon sources,especially in under-selected areas like the Northeast Java Basin.This region harbors promising unconventional hydrocarbon reserves,where source rocks function as dual-phase systems for both hydrocarbon generation and storage.This research investigates how metal-based catalysts,particularly iron(Fe),can expedite hydrocarbon maturation in such reservoirs.Combining well logging,geochemical assessments,seismic data,and advanced lab techniques,including X-ray Diffraction(XRD),we pinpoint optimal zones for exploration.Results indicate that the Tuban,Kujung,and Ngimbang formations contain economically viable unconventional deposits,exhibiting tight reservoir properties(permeability:0.01–1 md)and moderate to good Total Organic Carbon(TOC)levels(1%–2%).Spatial analysis reveals elevated density concentrations in the northern sector,indicative of high-viscosity hydrocarbons typical of unconventional plays.Crucially,Fe additives were found to markedly enhance organic matter conversion,shortening maturation periods and boosting hydrocarbon yield.XRD data confirms that Fe alters crystalline configurations,increasing reactivity and speeding up thermal breakdown(shifting immature organic compounds toward maturity at an accelerated rate).These findings contribute to the evolving discourse on unconventional resource exploitation by proposing an innovative recovery enhancement strategy.The study also sets a precedent for investigating metal-assisted hydrocarbon conversion in geologically comparable basins globally. 展开更多
关键词 Unconventional hydrocarbons hydrocarbon maturation metal catalysis geochemical analysis
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Effect of thermal maturation and organic matter content on oil shale fracturing 被引量:2
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作者 Fatemeh Saberi Mahboubeh Hosseini‑Barzi 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第2期16-34,共19页
The Pabdeh Formation represents organic matter enrichment in some oil fields,which can be considered a source rock.This study is based on the Rock–Eval,Iatroscan,and electron microscopy imaging results before and aft... The Pabdeh Formation represents organic matter enrichment in some oil fields,which can be considered a source rock.This study is based on the Rock–Eval,Iatroscan,and electron microscopy imaging results before and after heating the samples.We discovered this immature shale that undergoes burial and diagenesis,in which organic matter is converted into hydro-carbons.Primary migration is the process that transports hydrocarbons in the source rock.We investigated this phenomenon by developing a model that simulates hydrocarbon generation and fluid pressure during kerogen-to-hydrocarbon conversion.Microfractures initially formed at the tip/edge of kerogen and were filled with hydrocarbons,but as catagenesis progressed,the pressure caused by the volume increase of kerogen decreased due to hydrocarbon release.The transformation of solid kerogen into low-density bitumen/oil increased the pressure,leading to the development of damage zones in the source rock.The Pabdeh Formation’s small porethroats hindered effective expulsion,causing an increase in pore fluid pressure inside the initial microfractures.The stress accumulated due to hydrocarbon production,reaching the rock’s fracture strength,further contributed to damage zone development.During the expansion process,microfractures preferentially grew in low-strength pathways such as lithology changes,laminae boundaries,and pre-existing microfractures.When the porous pressure created by each kerogen overlapped,individual microfractures interconnected,forming a network of microfractures within the source rock.This research sheds light on the complex interplay between temperature,hydrocarbon generation,and the development of expulsion fractures in the Pabdeh Formation,providing valuable insights for understanding and optimizing hydrocarbon extraction in similar geological settings. 展开更多
关键词 Oil shale MICROFRACTURE Hydrocarbon generation Organic matter Thermal maturation Primary migration
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Endogenous biosynthesis of docosahexaenoic acid(DHA)regulates fish oocyte maturation by promoting pregnenolone production 被引量:2
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作者 Yi Li Xuehui Li +6 位作者 Ding Ye Ru Zhang Chengjie Liu Mudan He Houpeng Wang Wei Hu Yonghua Sun 《Zoological Research》 SCIE CSCD 2024年第1期176-188,共13页
Omega-3 polyunsaturated fatty acids(n-3 PUFAs),particularly docosahexaenoic acid(22:6n-3,DHA),play crucial roles in the reproductive health of vertebrates,including humans.Nevertheless,the underlying mechanism related... Omega-3 polyunsaturated fatty acids(n-3 PUFAs),particularly docosahexaenoic acid(22:6n-3,DHA),play crucial roles in the reproductive health of vertebrates,including humans.Nevertheless,the underlying mechanism related to this phenomenon remains largely unknown.In this study,we employed two zebrafish genetic models,i.e.,elovl2^(-/-)mutant as an endogenous DHAdeficient model and fat1(omega-3 desaturase encoding gene)transgenic zebrafish as an endogenous DHA-rich model,to investigate the effects of DHA on oocyte maturation and quality.Results show that the elovl2^(-/-)mutants had much lower fecundity and poorer oocyte quality than the wild-type controls,while the fat1 zebrafish had higher fecundity and better oocyte quality than wildtype controls.DHA deficiency in elovl2^(-/-)embryos led to defects in egg activation,poor microtubule stability,and reduced pregnenolone levels.Further study revealed that DHA promoted pregnenolone synthesis by enhancing transcription of cyp11a1,which encodes the cholesterol side-chain cleavage enzyme,thereby stabilizing microtubule assembly during oogenesis.In turn,the hypothalamic-pituitary-gonadal axis was enhanced by DHA.In conclusion,using two unique genetic models,our findings demonstrate that endogenously synthesized DHA promotes oocyte maturation and quality by promoting pregnenolone production via transcriptional regulation of cyp11a1. 展开更多
关键词 Docosahexaenoic acid Oocyte maturation Oocyte quality PREGNENOLONE MICROTUBULE
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CRISPR/Cas9-mediated knockout of E4 gene promotes maturation in soybean 被引量:3
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作者 Shuiqing Wu Li Chen +7 位作者 Mengwei Guo Yupeng Cai Yang Gao Shan Yuan Shi Sun Yuxian Zhang Wensheng Hou Tianfu Han 《Oil Crop Science》 CSCD 2024年第3期170-176,共7页
Soybean is a broadly popular and extensively cultivated crop,however,many high-yield and high-quality varieties require specific growth conditions,restricting their widespread adoption.The appropriate light conditions... Soybean is a broadly popular and extensively cultivated crop,however,many high-yield and high-quality varieties require specific growth conditions,restricting their widespread adoption.The appropriate light conditions and photoperiod must be attained for these varieties to thrive in new environments.In this study,we employed CRISPR/Cas9 to design two sgRNAs aimed at knocking out the maturity-related gene E4 in a major American soybean variety called''Jack'',which belongs to maturity group MGII.E4 gene is primarily involved in the photoperiodic flowering and maturity in soybean,making it an ideal candidate for genetic manipulation.We successfully obtained 1 homozygous E4-SG1 mutant type with 1-bp insertion,and 4 homozygous E4-SG2 mutants type with 2-bp deletion,7-bp deletion,61-bp deletion,and 1-bp insertion,respectively.The homozygous e4 mutant plants contained early termination codons devoid of transgenic elements.Additionally,no potential offtarget sites of the E4 gene were detected.A comparative analysis revealed that,unlike the wild-type,the maturity time of homozygous e4 mutants was early under both short-day and long-day conditions.These mutants offer novel germplasm resources that may be used to modify the photoperiod sensitivity and maturity of soybean,enhancing its adaptability to high-latitude regions. 展开更多
关键词 SOYBEAN E4 CRISPR/Cas9 MATURITY
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Impact of stage-specific limb function exercises guided by a selfmanagement education model on arteriovenous fistula maturation status 被引量:2
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作者 Yi Li Li-Jun Huang +1 位作者 Jian-Wen Hou Dan-Dan Hu 《World Journal of Clinical Cases》 SCIE 2024年第14期2316-2323,共8页
BACKGROUND The exercise of limb function is the most economical and safe method to promote the maturation of arteriovenous fistula(AVF).However,due to the lack of a uni-fied exercise standard in China,many patients ha... BACKGROUND The exercise of limb function is the most economical and safe method to promote the maturation of arteriovenous fistula(AVF).However,due to the lack of a uni-fied exercise standard in China,many patients have insufficient awareness of the importance of AVF,leading to poor effectiveness of limb function exercise.The self-management education model can effectively promote patients to take pro-active health-related actions.This study focuses on the characteristics of patients during the peri-AVF period and conducts a phased limb function exercise under the guidance of the self-management education model to observe changes in fac-tors such as the maturity of AVF.AIM To assess the impact of stage-specific limb function exercises,directed by a self-management education model,on the maturation status of AVFs.METHODS This study is a randomized controlled trial involving 74 patients with forearm AVFs from the Nephrology Department of a tertiary hospital in Sichuan Province,China.Patients were randomly divided into an observation group and a control group using a random number table method.The observation group underwent tailored stage-specific limb func-tion exercises,informed by a self-management education model which took into account the unique features of AVF at various stages,in conjunction with routine care.Conversely,the control group was given standard limb function exercises along with routine care.The assessment involves the maturity of AVFs post-intervention,post-operative complications,and the self-management level of the fistula in both groups patients.Analyses were conducted using SPSS version 23.0.Count data were represented by frequency and percentage and subjected to chi-square test comparisons.Measurement data adhering to a normal distribution were presented as mean±SD.The independent samples t-test was utilized for inter-group comparisons,while the paired t-test was used for intra-group comparisons.For measurement data not fitting a normal distribution,the median and interquartile range were presented and analyzed using the Wilcoxon rank sum test.RESULTS At the 8-wk postoperative mark,the observation group demonstrated significantly higher scores in AVF symptom recognition,symptom prevention,and self-management compared to the control group(P<0.05).However,the variance in symptom management scores between the observation and control groups lacked statistical signi-ficance(P>0.05).At 4 wk after the operation,the observation group displayed a superior vessel diameter and depth from the skin of the drainage vessels in comparison to the control group(P<0.05).While the observation group did manifest elevated blood flow rates in the drainage vessels relative to the control group,this distinction was not statistically significant(P>0.05).By the 8-wk postoperative interval,the observation group outperformed the control group with notable enhancements in blood flow rates,vessel diameter,and depth from the skin of drainage vessels(P<0.01).Seven days following the procedure,the observation group manifested significantly diminished limb swelling and an overall reduced complication rate in contrast to the control group(P<0.05).The evaluation of infection,thrombosis,embolism,arterial aneurysm stenosis,and incision bleeding showed no notable differences between the two groups(P>0.05).By the 4-wk postoperative juncture,complications between the observation and control groups were statistically indistinguishable(P>0.05).CONCLUSION Stage-specific limb function exercises,under the guidance of a self-management education model,amplify the capacity of AVF patients to discern and prevent symptoms.Additionally,they expedite AVF maturation and miti-gate postoperative limb edema,underscoring their efficacy as a valuable method for the care and upkeep of AVF in hemodialysis patients. 展开更多
关键词 SELF-MANAGEMENT Education model Stage-specific Limb function exercises Arteriovenous fistula maturation status
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Enhancer of Shoot Regeneration 2(ESR2)regulates pollen maturation and vitality in watermelon(Citrullus lanatus)
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作者 Hu Wang Lihong Cao +2 位作者 Yalu Guo Zheng Li Huanhuan Niu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3506-3521,共16页
Watermelon(Citrullus lanatus)holds global significance as a fruit with high economic and nutritional value.Exploring the regulatory network of watermelon male reproductive development is crucial for developing male st... Watermelon(Citrullus lanatus)holds global significance as a fruit with high economic and nutritional value.Exploring the regulatory network of watermelon male reproductive development is crucial for developing male sterile materials and facilitating cross-breeding.Despite its importance,there is a lack of research on the regulation mechanism of male reproductive development in watermelon.In this study,we identified that ClESR2,a VIIIb subclass member in the APETALA2/Ethylene Responsive Factor(AP2/ERF)superfamily,was a key factor in pollen development.RNA insitu hybridization confirmed significantClESR2 expression in the tapetum and pollen during the later stage of anther development.The pollens of transgenic plants showed major defects in morphology and vitality at the late development stage.The RNA-seq and protein interaction assay confirmed that ClESR2 regulates pollen morphology and fertility by interacting with key genes involved in pollen development at both transcriptional and protein levels.These suggest that Enhancer of Shoot Regeneration 2(ESR2)plays an important role in pollen maturation and vitality.This study helps understand the male reproductive development of watermelon,providing a theoretical foundation for developing male sterile materials. 展开更多
关键词 ESR2 WATERMELON OVEREXPRESSION pollen maturation pollen vitality
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职业教育数字化转型能力成熟度模型与评估方法 被引量:4
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作者 邱飞岳 张彭丽 +2 位作者 袁霄 黄江 郭海东 《远程教育杂志》 北大核心 2025年第1期75-84,共10页
教育数字化转型是推动全球教育革新和重塑竞争优势的重要方向。职业教育,作为经济社会发展的关键动力,正在主动求变、积极应变。为了科学有效地评估职业院校的数字化转型程度及能力,研究基于成熟度模型视角,提出了切实可行的评估方案。... 教育数字化转型是推动全球教育革新和重塑竞争优势的重要方向。职业教育,作为经济社会发展的关键动力,正在主动求变、积极应变。为了科学有效地评估职业院校的数字化转型程度及能力,研究基于成熟度模型视角,提出了切实可行的评估方案。具体而言,研究首先从院校个体、群体标杆、职教蓝图三个层面展开价值探索,系统剖析了成熟度模型的构成要素及教育数字化转型成熟度模型的共性特征;其次,结合我国职业教育数字化发展特色,构建了一个包含五个成熟度等级、四个能力要素、九个能力域和二十五个能力子域的职业教育数字化转型能力成熟度模型;最后,详细阐述了评估方法与实施流程。该模型旨在帮助职业院校评估自身数字化转型能力成熟度,识别发展瓶颈,进而采取针对性的措施提升数字化水平,以更好地适应现代职业教育高质量发展的需求。 展开更多
关键词 职业教育数字化 能力成熟度模型 成熟度等级 评估方法与流程
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基于轻量化YOLO v5s-MCA的番茄成熟度检测方法 被引量:5
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作者 奚小波 丁杰源 +5 位作者 翁小祥 王昱 韩连杰 邹赟涵 唐子昊 张瑞宏 《农业机械学报》 北大核心 2025年第3期383-391,436,共10页
针对自然环境下番茄识别易受复杂背景干扰、相邻果实成熟度相似难以检测等问题,本文提出了一种轻量化YOLO v5s-MCA番茄成熟度识别模型,划分成熟期、转熟期、转色期和未熟期4个成熟度等级。该模型在YOLO v5s基础上使用MobileNetV3网络,... 针对自然环境下番茄识别易受复杂背景干扰、相邻果实成熟度相似难以检测等问题,本文提出了一种轻量化YOLO v5s-MCA番茄成熟度识别模型,划分成熟期、转熟期、转色期和未熟期4个成熟度等级。该模型在YOLO v5s基础上使用MobileNetV3网络,减少了模型参数量;在主干网络和颈部网络引入坐标注意力机制(Coordinate attention,CA),提高了模型对番茄特征表达能力;将颈部网络替换为加权双向特征金字塔网络BiFPN,强化了模型特征融合性能并提高了模型识别准确率;将颈部网络中的标准卷积模块改进为GSConv卷积,减轻了模型复杂度并提高了对目标信息的获取能力。试验结果表明,YOLO v5s-MCA模型参数量仅为2.33×10^(6),计算量仅为4.1×10^(9),模型内存占用量仅为4.83 MB,其精准度和平均精度均值分别达到92.8%和95.1%,相对YOLO v5s基础模型分别提升3.4、4.4个百分点。对比YOLO v3s、YOLO v5s、YOLO v5n、YOLO v7、YOLO v8n及YOLO v10n等6种模型,YOLO v5s-MCA模型轻量化效果与检测性能最优。 展开更多
关键词 番茄 成熟度检测 图像识别 YOLO v5s 轻量化
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基于改进YOLO v8n网络的番茄成熟度实时检测算法 被引量:6
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作者 任晶秋 万恩晗 +2 位作者 单蜜 张光华 卢为党 《农业机械学报》 北大核心 2025年第3期374-382,450,共10页
为应对番茄采摘面临的果农老龄化、劳动力短缺和人工成本上涨等挑战,解决在复杂果园环境下番茄采摘机器人视觉系统成熟度检测精度低和实例分割不准确等问题,本文提出一种基于改进YOLO v8n网络的番茄成熟度实时检测算法。首先,通过在YOLO... 为应对番茄采摘面临的果农老龄化、劳动力短缺和人工成本上涨等挑战,解决在复杂果园环境下番茄采摘机器人视觉系统成熟度检测精度低和实例分割不准确等问题,本文提出一种基于改进YOLO v8n网络的番茄成熟度实时检测算法。首先,通过在YOLO v8n网络中引入通道嵌入位置注意力模块和改进大核卷积块注意力模块,能够在浅层网络保留番茄目标位置信息,建立目标区域之间的长距离依赖关系,从而增加YOLO v8n网络对显著番茄特征的关注。然后,在LaboroTomato数据集上进行了对比实验,改进YOLO v8n相较于原YOLO v8n网络,检测和分割的mAP@50和mAP@50-95分别提高0.4、1.4个百分点和0.3、1.2个百分点。最后,实现了改进YOLO v8n网络在低成本、低算力和低功耗的Jetson Nano平台上的轻量化部署,模型内存占用量由满溢减少到2.4 GB,推理速度加倍。该研究可为番茄采摘机器人在复杂场景下实时、准确检测番茄成熟度提供技术支撑。 展开更多
关键词 番茄成熟度 目标检测 YOLO v8n 注意力模块 轻量化 Jetson Nano
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成熟度和温度对芙蓉李贮藏期间生理生化特性及蜡质结构的影响 被引量:1
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作者 周丹蓉 叶新福 +1 位作者 方智振 林炎娟 《核农学报》 CAS 北大核心 2025年第1期128-139,共12页
为研究成熟度和温度对芙蓉李贮藏期间生理生化特性和果皮蜡质结构的影响,本研究选择2个成熟度(F:约六成熟;S:约八成熟)的芙蓉李,于4、25℃条件下进行试验,分析16个生理生化指标的差异,采用正交偏最小二乘判别法(OPLS-DA)筛选不同成熟度... 为研究成熟度和温度对芙蓉李贮藏期间生理生化特性和果皮蜡质结构的影响,本研究选择2个成熟度(F:约六成熟;S:约八成熟)的芙蓉李,于4、25℃条件下进行试验,分析16个生理生化指标的差异,采用正交偏最小二乘判别法(OPLS-DA)筛选不同成熟度芙蓉李在不同温度贮藏期间的主要差异性指标,检测芙蓉李贮藏前后蜡质结构的变化并分析其贮藏效应。结果表明,4℃条件下F与S之间的主要差异性指标为可溶性固形物含量(SS)、果肉硬度(FF)、果皮色度值a^(*)(PC-a^(*))、花色苷(AC)含量、可滴定酸(TA)含量、果皮硬度(PF),25℃时为SS、超氧化物歧化酶(SOD)活性、PC-a^(*)、果皮色度值b*(PC-b*)。不同成熟度果实的SS含量、PC-a^(*)、AC含量均随贮藏天数增加而逐渐上升(S贮藏28 d除外),同一贮藏天数下AC含量在25℃时显著高于4℃时,同一温度同一贮藏天数时S中的SS含量、PC-a^(*)显著高于F;PF、FF和TA含量随贮藏天数的延长而逐渐下降,4℃和F有利于FF和PF的保持,而25℃下TA含量下降更快;SOD活性随贮藏天数的延长先升高后下降,且在25℃和S中下降更显著。芙蓉李蜡质主要以直立片状晶体和颗粒状结晶的形式存在;两种晶体数量和形态的变化可能影响水分的流失,从而影响细胞壁结构的稳定性,进而影响贮藏性。本研究可为芙蓉李的采收和贮藏保鲜提供技术参考。 展开更多
关键词 芙蓉李 成熟度 贮藏温度 生理生化特性 蜡质结构
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中晚熟马铃薯新品种克新40的选育 被引量:1
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作者 李凤云 王立春 +5 位作者 田国奎 王海艳 娄树宝 潘阳 庞泽 丁凯鑫 《中国瓜菜》 北大核心 2025年第3期178-182,共5页
克新40是以CIP393371.157为母本、以尤金为父本杂交选育而成的中晚熟鲜食型、薯条加工兼用型马铃薯新品种。该品种在黑龙江省春季栽培从出苗至成熟86 d左右。株型半直立,株高约65.3 cm。茎、叶绿色,茎翼微波状。花序小,花冠紫色,近五边... 克新40是以CIP393371.157为母本、以尤金为父本杂交选育而成的中晚熟鲜食型、薯条加工兼用型马铃薯新品种。该品种在黑龙江省春季栽培从出苗至成熟86 d左右。株型半直立,株高约65.3 cm。茎、叶绿色,茎翼微波状。花序小,花冠紫色,近五边形。结薯集中,薯块短卵圆形,表皮略麻,黄皮带有部分紫色,黄肉,芽眼深度中,单株结薯数6~10个,平均单薯质量152.3 g,商品薯(>75 g)率在83.33%~92.0%,667 m^(2)产量3200 kg左右。高抗晚疫病,中抗PVX病毒病,抗PVY病毒病,耐贮藏。干物质含量(w,后同)16.4%,淀粉含量12.4%,粗蛋白含量1.34%,维生素C含量33.6 mg·100 g^(-1),还原糖含量0.45%。适宜在黑龙江省各生态区种植。2023年通过农业农村部非主要农作物品种登记。 展开更多
关键词 马铃薯 新品种 克新40 中晚熟
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花生荚果力学特性评鉴及早熟种质筛选 被引量:2
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作者 迟晓元 毕竞男 +7 位作者 赵健鑫 陈娜 潘丽娟 姜骁 殷祥贞 赵旭红 马俊卿 许静 《作物学报》 北大核心 2025年第4期943-957,共15页
花生荚果的力学特性是花生机械化收获的重要参考指标,早熟品种的筛选是满足市场需求和提高农业生产效益的重要举措。本研究以499份来自世界各地的花生种质资源为材料,对其果柄强度、荚果破壳力和成熟率等指标进行测定和分析。果柄强度... 花生荚果的力学特性是花生机械化收获的重要参考指标,早熟品种的筛选是满足市场需求和提高农业生产效益的重要举措。本研究以499份来自世界各地的花生种质资源为材料,对其果柄强度、荚果破壳力和成熟率等指标进行测定和分析。果柄强度测定结果显示,499份种质材料之间变异广泛(3.55~15.54 N),265份种质的成熟荚果果柄强度(7.13 N)大于未成熟荚果果柄强度(6.99N),38份种质材料的果柄强度在不同成熟度之间存在显著或极显著差异;平均秧-柄脱落力(7.51N)大于果-柄脱落力(7.11N),48份种质材料在秧-柄节点的脱落力显著或极显著高于果-柄节点;荚果侧压破壳力>正压破壳力>立压破壳力,3个方向的荚果破壳力两两之间均存在极显著差异;花生荚果的果柄强度与果-柄脱落力的相关性最大(r=0.99,P<0.01);花生荚果力学特性的13个性状综合成为4个主成分因子,累计贡献率为63.83%;多元回归分析表明,果-柄脱落力、果-柄脱落百分率、荚果层厚度、未熟荚果果柄强度和秧-柄脱落力是影响果柄强度的主要性状;最终筛选出16份荚果力学特性优异、早熟的优异种质资源,为后续培育早熟且适应机械化收获的花生新品种提供参考。 展开更多
关键词 花生 荚果力学特性 果柄强度 荚果破壳力 成熟度
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气候风险与企业投融资期限错配 被引量:7
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作者 李香花 谢梦瑶 王敏 《现代财经(天津财经大学学报)》 北大核心 2025年第3期101-114,共14页
气候变化及其引发的风险对金融市场和实体经济造成了严重冲击,本文基于2007—2022年沪深两市A股上市公司数据,考察了气候风险对企业投融资期限错配的影响。研究发现:气候风险加剧了企业的投融资期限错配,该结论在经过一系列稳健性与内... 气候变化及其引发的风险对金融市场和实体经济造成了严重冲击,本文基于2007—2022年沪深两市A股上市公司数据,考察了气候风险对企业投融资期限错配的影响。研究发现:气候风险加剧了企业的投融资期限错配,该结论在经过一系列稳健性与内生性检验后依然成立。作用机制检验表明,气候风险通过在投资端增加企业的长期投资需求、在融资端增强企业的融资约束,加剧了企业投融资期限错配。异质性分析发现,气候风险对企业投融资期限错配的促进作用在抵押能力弱、研发密集度高、规模小的企业以及环境规制力度强的地区更显著。经济后果检验表明,上述负面影响会进一步提高企业的破产风险,削弱了实体经济的可持续性。本文丰富了气候风险和企业投融资行为的相关研究,所得结论有助于政府相关部门关注当前生态文明建设背景下的企业投融资期限错配问题,优化金融结构,加强气候韧性建设。 展开更多
关键词 气候风险 投融资期限错配 长期投资需求 融资约束
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基于最大熵模型(Max Ent)和地理信息系统(GIS)的四川省眉山市东坡区晚熟柑橘适宜性评价 被引量:1
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作者 姚莉 邓春秀 +7 位作者 唐彪 王宏 吴月颖 张奇 李源洪 刘忠友 卢昌艾 林超文 《中国农业科学》 北大核心 2025年第4期748-758,共11页
【目的】开展四川省眉山市东坡区晚熟柑橘适宜性评价,可为当地晚熟柑橘合理种植、优化生产空间提供科学参考。【方法】基于14个气候指标、3个地形指标和22个土壤理化性状指标,以及372个晚熟柑橘种植区采样点数据,利用最大熵模型(MaxEnt... 【目的】开展四川省眉山市东坡区晚熟柑橘适宜性评价,可为当地晚熟柑橘合理种植、优化生产空间提供科学参考。【方法】基于14个气候指标、3个地形指标和22个土壤理化性状指标,以及372个晚熟柑橘种植区采样点数据,利用最大熵模型(MaxEnt)和地理信息系统(GIS)结合相关性分析筛选影响四川省眉山市东坡区晚熟柑橘分布的关键环境因子,构建评价晚熟柑橘种植适宜性模型。【结果】MaxEnt模型计算效果非常好,受试者特征工作曲线(ROC曲线)中的下面积值(AUC)达0.843,具有较高的准确性与可靠性。MaxEnt分析表明,年平均气温、海拔、全磷、pH、年平均相对湿度、粉粒量、年降水量、年日照时数、秋季降水量、土壤交换性钙、全钾和有机质是影响晚熟柑橘分布的主要环境因子。影响柑橘分布的气候变量累计贡献率为43.0%,其中,年平均气温(22.9%)、年平均相对湿度(7.0%)和年降水量(4.6%)是影响晚熟柑橘分布的3个最主要的气候因子;影响晚熟柑橘分布的土壤变量累计贡献率为41.3%,其中,全磷(13.8%)、pH(10.4%)和粉粒量(5.7%)是影响晚熟柑橘分布的3个最主要的土壤因子;海拔是影响柑橘分布的地形因子,贡献率为15.7%。通过统计分析各主导环境因子在不同等级分布区的参数值,结合各生态因子响应曲线、实地调查情况以及查阅文献,综合分析得出晚熟柑橘适宜分布的基本气候和地形环境要求为:年平均气温17℃左右,年平均相对湿度80%,年降雨量1300 mm左右,年日照时数1350 h,秋季降雨量390 mm,海拔400—700 m;土壤pH为4.5—7.5,土壤养分状况受立地条件和栽培管理措施的综合影响。全区34673.29 hm~2的宜园土地中,优势区、适宜区和不适宜区分别占23.51%、61.37%和15.12%。【结论】客观地反映了在气候、地形和土壤因素影响下,东坡区晚熟柑橘种植适宜性变化特征、适宜性面积及分布。 展开更多
关键词 晚熟柑橘 最大熵模型 地理信息系统 适宜性评价
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政府审计如何影响企业投融资期限错配? 被引量:1
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作者 张娟 李伟 《审计研究》 北大核心 2025年第3期51-63,共13页
政府审计作为一项重要的外部监督治理机制,探究其对企业投融资期限错配的作用有助于防范和化解系统性金融风险。本文以中央企业控股的上市公司为对象,研究了政府审计对企业投融资期限错配的作用。研究发现,政府审计显著抑制了企业投融... 政府审计作为一项重要的外部监督治理机制,探究其对企业投融资期限错配的作用有助于防范和化解系统性金融风险。本文以中央企业控股的上市公司为对象,研究了政府审计对企业投融资期限错配的作用。研究发现,政府审计显著抑制了企业投融资期限错配的程度。异质性分析表明,如果审计结果公告关注企业投融资、发现违法行为并移送司法机关,政府审计对企业投融资期限错配的抑制作用就更显著;政府审计对投融资期限错配的抑制作用在市场化程度低、企业信息透明度差、公司治理水平低及非国际“四大”审计的企业中更强。作用机制研究表明,政府审计通过降低企业的代理成本和过度投资来降低企业投融资期限错配。 展开更多
关键词 政府审计 投融资期限错配 代理成本 过度投资
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战略联盟何以抑制企业投融资期限错配?--“开源”和“节流”的双重视角 被引量:1
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作者 陈红 朱震 +1 位作者 赵荣权 胡耀丹 《现代金融研究》 北大核心 2025年第3期84-99,共16页
本文基于2009-2022年中国A股上市公司发布的战略联盟合作公告数据,探讨战略联盟对企业投融资期限错配的影响。研究发现,战略联盟整体改善了企业投融资期限错配,这得益于融资端的“开源”效应和投资端的“节流”效应,战略联盟能显著提升... 本文基于2009-2022年中国A股上市公司发布的战略联盟合作公告数据,探讨战略联盟对企业投融资期限错配的影响。研究发现,战略联盟整体改善了企业投融资期限错配,这得益于融资端的“开源”效应和投资端的“节流”效应,战略联盟能显著提升银行发放长期贷款的意愿,同时减少企业的长期资金支出,抑制企业“短贷长投”。进一步分析表明,战略联盟显著提升了企业的长期借款占比,增加的长期借款主要被用于期限较长的固定资产投资。此外,当企业内源融资不足、外部融资环境较差、联盟类别为横向联盟和股权式联盟时,战略联盟的投融资期限错配抑制效应更显著。 展开更多
关键词 战略联盟 期限错配 非正式制度 长期资金
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