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A test of genetic divergence of a bird existing in the Sichuan Basin and its surrounding mountain ranges
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作者 Lu Wang Fangqing Liu +3 位作者 Lan Zhao yaling xu Tianyu Zhang Longying Wen 《Avian Research》 SCIE CSCD 2023年第4期553-564,共12页
Island ecosystems,serving as natural laboratories,facilitate geographical isolation,ecological specialization,and species divergence.The Sichuan Basin,surrounded by mountain ranges,represents a typical continental isl... Island ecosystems,serving as natural laboratories,facilitate geographical isolation,ecological specialization,and species divergence.The Sichuan Basin,surrounded by mountain ranges,represents a typical continental island due to its marked environmental spatial heterogeneity.This heterogeneity may contribute to geographical isolation and habitat heterogeneity,resulting in genetic divergence within populations.Therefore,we used the White-browed Laughingthrush(Garrulax sannio)as a model specimen to investigate the genetic divergence in the Sichuan Basin and its surrounding mountain ranges,given its presence in various habitats within and beyond this basin.Employing a RAD-seq dataset of 140 G.sannio individuals from 17 distinct ecological zones in the Sichuan Basin and its surrounding mountain ranges,we conducted PCA,population structure analysis,phylogenetic tree construction,and gene flow analysis to comprehensively analyze G.sannio groups.Additionally,in conjunction with geographical and ecological data,we performed isolation by distance,isolation by environment,PCA,and latent factor mixed model analysis to identify factors influencing the genetic divergence among these G.sannio groups.In summary,the 17 G.sannio groups were categorized into high-elevation,medium-elevation,and lowelevation groups.Genetic divergence in G.sannio may be attributed to both geographical distance and key ecological factors,particularly elevation and key climatic variables.Notably,the high-elevation group exhibited a greater number of SNPs and selected genes associated with the key ecological factors compared to the lowelevation group.The ADCY9 gene and several associated key pathways were identified as crucial elements driving ecological adaptation(elevation and key climatic variables)in the high-elevation group.Furthermore,climate changes during the glacial cycles may have facilitated gene flow among these groups residing in the Sichuan Basin and its surrounding mountain ranges.Our findings provide evidence of genetic divergence in G.sannio influenced by the geographical distance and key ecological factors between the Sichuan Basin and its surrounding mountain ranges.These results lay the groundwork for future research on the molecular systematics of continental islands. 展开更多
关键词 Genetic divergence Restriction site-associated DNA sequencing (RAD-seq) Sichuan Basin White-browed Laughingthrush
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Novel Early-Warning Model for Customer Churn of Credit Card Based on GSAIBAS-Cat Boost
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作者 yaling xu Congjun Rao +1 位作者 Xinping Xiao Fuyan Hu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第12期2715-2742,共28页
As the banking industry gradually steps into the digital era of Bank 4.0,business competition is becoming increasingly fierce,and banks are also facing the problem of massive customer churn.To better maintain their cu... As the banking industry gradually steps into the digital era of Bank 4.0,business competition is becoming increasingly fierce,and banks are also facing the problem of massive customer churn.To better maintain their customer resources,it is crucial for banks to accurately predict customers with a tendency to churn.Aiming at the typical binary classification problem like customer churn,this paper establishes an early-warning model for credit card customer churn.That is a dual search algorithm named GSAIBAS by incorporating Golden Sine Algorithm(GSA)and an Improved Beetle Antennae Search(IBAS)is proposed to optimize the parameters of the CatBoost algorithm,which forms the GSAIBAS-CatBoost model.Especially,considering that the BAS algorithm has simple parameters and is easy to fall into local optimum,the Sigmoid nonlinear convergence factor and the lane flight equation are introduced to adjust the fixed step size of beetle.Then this improved BAS algorithm with variable step size is fused with the GSA to form a GSAIBAS algorithm which can achieve dual optimization.Moreover,an empirical analysis is made according to the data set of credit card customers from Analyttica official platform.The empirical results show that the values of Area Under Curve(AUC)and recall of the proposedmodel in this paper reach 96.15%and 95.56%,respectively,which are significantly better than the other 9 common machine learning models.Compared with several existing optimization algorithms,GSAIBAS algorithm has higher precision in the parameter optimization for CatBoost.Combined with two other customer churn data sets on Kaggle data platform,it is further verified that the model proposed in this paper is also valid and feasible. 展开更多
关键词 Customer churn early-warning model IBAS GSAIBAS-CatBoost
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Molecular Cloning, Sequence Analysis and Expression Analysis of an NtWRKY6 from Tobacco (<i>Nicotiana tabacum</i>L.) in Abiotic Strsss
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作者 Liqin Li Yubi Huang +1 位作者 Wei Wang yaling xu 《American Journal of Plant Sciences》 2012年第11期1520-1526,共7页
In higher plants, WRKY gene family plays a significant role in transcriptional regulation. They are widely involved in biotic stress, abiotic stress, growth, development and metabolism regulation. In this study WRKY6 ... In higher plants, WRKY gene family plays a significant role in transcriptional regulation. They are widely involved in biotic stress, abiotic stress, growth, development and metabolism regulation. In this study WRKY6 from tobacco is cloned by homology cloning. 1647 nucleotide sequences were obtained. The deduced protein sequences show that this protein belongs to the second group of WRKY family, only have one WRKY structure, and the zinc-finger structure is C-X4-C-X23-H-X1-H. Phylogeny results show NtWRKY6 is much closer to NtWRKY1 generated 97% amino acids similarity. RT-PCR analysis has revealed that expression levels of NtWRKY6 has increased rapidly at 3 h under NaCI and PEG treatment. The results suggest that NtWRKY6 is an early responder and may be involved in NaCl and PEG abiotic stress in tobacco. 展开更多
关键词 WRKY Protein Molecular Cloning TOBACCO RT-PCR Expression Analysis
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产前地塞米松和生后肺表面活性物质联合呼吸支持对早产兔肺液清除的作用
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作者 尤小寒 马莉 +4 位作者 安会波 罗四维 许亚玲 郭晓菁 孙波 《中华围产医学杂志》 CAS CSCD 北大核心 2023年第4期315-324,共10页
目的探讨产前地塞米松(dexamethasone,DEX)、生后肺表面活性物质(pulmonary surfactant,PS)及呼吸支持对胎龄25~28 d(足月31 d)早产兔出生早期肺液清除效率的影响,及其与呼吸系统动态顺应性(dynamic compliance of respiratory system,C... 目的探讨产前地塞米松(dexamethasone,DEX)、生后肺表面活性物质(pulmonary surfactant,PS)及呼吸支持对胎龄25~28 d(足月31 d)早产兔出生早期肺液清除效率的影响,及其与呼吸系统动态顺应性(dynamic compliance of respiratory system,Cdyn)、肺病理形态学等参数的关系。方法本课题组已发表动物研究将早产兔依据干预分为对照组、仅PS组、仅DEX组和DEX+PS组。本研究收集上述已发表动物研究中的肺湿干重比值(wet-to-dry lung weight ratio,W/D)、Cdyn、肺泡扩张度(volume density of alveoli,Vv)等参数;并对其肺组织病理切片扫描成像,进行二次测量,计算肺血管周围袖带与血管切面面积比(ratio of perivascular sheath to vascular sectional area,S/V)和肺损伤水肿评分(lung injury scores-edema,LIS-E)。将W/D、LIS-E、S/V、Vv经出生体重(birth weight,BW)修正(除以BW,分别以W/D/BW、LIS-E/BW、S/V/BW、Vv/BW表示),Cdyn取均值(mean Cdyn,Cdyn-m)。延用上述已发表动物研究的分组,并进行新的混合干预分组(用DEX组和未用DEX组、用PS组和未用PS组),分析DEX及PS对上述参数的影响及各参数之间的相关性。采用两独立样本t检验、单因素方差分析、LSD检验、Kruskal-Wallis H检验、Mann-Whitney U检验及Pearson相关分析进行统计学分析。结果共196只生后接受机械通气的新生兔的肺病理切片及相关数据纳入本研究。(1)DEX对各指标的影响:用DEX组与未用DEX组相比,胎龄25 d时W/D/BW(489±69与421±113,t=-2.09)、LIS-E/BW(188±57与138±55,t=-2.61)和Vv/BW升高(20.1±4.9与14.2±4.7,t=-3.60),S/V(0.33±0.23与0.51±0.25,t=2.23)和S/V/W/D降低(0.05±0.03与0.07±0.04,t=2.22);胎龄26 d时W/D/BW(472±76与303±44,t=-8.75)、LIS-E/BW(189±63与106±36,t=-5.23)、Cdyn-m[(0.16±0.07)与(0.05±0.03)ml/(kg∙cmH2O),1 cmH2O=0.098 kPa,t=-7.29]和Vv/BW升高(22.4±5.0与12.2±3.8,t=-7.46),S/V(0.23±0.19与0.62±0.38,t=4.10)、S/V/BW(15.7±12.4与25.7±17.3,t=2.20)、S/V/W/D(0.03±0.03与0.08±0.05,t=3.92)和倾向性评分降低[(12.5±1.2)与(15.1±1.2)分,t=7.00];胎龄27 d时Cdyn-m升高[(0.23±0.12)与(0.16±0.07)ml/(kg∙cmH2O),t=-2.43],S/V(0.32±0.23与0.57±0.39,t=2.57)和S/V/W/D降低(0.05±0.04与0.09±0.06,t=2.55);胎龄28 d时W/D/BW(270±64与162±33,t=-8.09)、LIS-E/BW(72±32与35±20,t=-5.17)、S/V(0.90±0.60与0.59±0.48,t=-2.81)、S/V/BW(34.0±23.6与15.2±12.7,t=-3.77)和Vv/BW升高(16.9±4.3与9.2±2.9,t=-8.04);差异均有统计学意义(P值均<0.05)。(2)PS对各指标的影响:用PS组与未用PS组相比,胎龄25、26和27 d时LIS-E/BW降低,胎龄25和27 d时Cdyn-m和Vv/BW升高,胎龄25 d时倾向性评分升高,差异均有统计学意义(P值均<0.05)。(3)胎龄与各指标的相关性:胎龄与S/V呈正相关(r=0.31),与W/D/BW、LIS-E/BW均呈负相关(r值分别为-0.73和-0.63),差异均有统计学意义(P值均<0.05)。结论产前应用DEX对胎龄28 d机械通气早产兔肺液清除有促进作用,但对胎龄25~27 d兔,在应用产前DEX和/或生后PS后,生后早期呼吸功能虽得到改善,但未发现对肺液清除有明显促进作用。胎龄相关的肺成熟度对早产兔肺液清除起主要作用。 展开更多
关键词 早产 糖皮质激素类 肺表面活性剂 呼吸 人工 肺泡 婴儿 新生 疾病模型 动物
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