In this study,the morphology and ultrastructure of the compound eye of L.lewisii were investigated using scanning electron microscopy(SEM),transmission electron microscopy(TEM),microcomputed tomography(μCT),and 3D re...In this study,the morphology and ultrastructure of the compound eye of L.lewisii were investigated using scanning electron microscopy(SEM),transmission electron microscopy(TEM),microcomputed tomography(μCT),and 3D reconstruction.The compound eye of L.lewisii was of the apposition type,with an average of 121.88±7.64 ommatidia in males and 119.00±4.71 ommatidia in females.Each ommatidium was composed of a biconvex cornea,an acone consisting of four cone cells,eight retinular cells along with the rhabdom,two primary pigment cells,and numerous secondary pigment cells.The open type of rhabdom in L.lewisii consists of six peripheral rhabdomeres contributed by the six peripheral retinular cells(R1~R6)and two vertically attached central rhabdomeres contributed by R7 and R8 respectively.The orientation of microvilli suggested a weak sensitivity to polarized light perception.展开更多
This paper studies online scheduling of jobs with kind release times on a single machine. Here "kind release time" means that in online setting, no jobs can be released when the machine is busy. Each job J h...This paper studies online scheduling of jobs with kind release times on a single machine. Here "kind release time" means that in online setting, no jobs can be released when the machine is busy. Each job J has a kind release time r(J) ≥ 0, a processing time p(J) > 0 and a deadline d(J) > 0. The goal is to determine a schedule which maximizes total processing time( p(J)E(J)) or total number( E(J)) of the accepted jobs. For the first objective function p(J)E(J), we first present a lower bound 2(1/2), and then provide an online algorithm LEJ with a competitive ratio of 3. This is the first deterministic algorithm for the problem with a constant competitive ratio. When p(J) ∈ {1, k}, k > 1 is a real number, we first present a lower bound min{(1 + k)/k, 2 k/(1 + k)}, and then we show that LEJ has a competitive ratio of1 + k/k. In particular, when all the k length jobs have tight deadlines, we first present a lower bound max{4/(2 + k), 1}(for p(J)E(J)) and 4/3(for E(J)). Then we prove that LEJ is k/k-competitive for p(J)E(J) and we provide an online algorithm H with a competitive ratio of 2 k/( k + 1) for the second objective function E(J).展开更多
Hybrid rice significantly contributes to the food supply worldwide. Backbone parents play important roles in elite hybrid rice breeding systems. In this study, we performed pedigree-based analysis of the elite backbon...Hybrid rice significantly contributes to the food supply worldwide. Backbone parents play important roles in elite hybrid rice breeding systems. In this study, we performed pedigree-based analysis of the elite backbone parent rice variety, namely, Shuhui 527(SH527, Oryza sativa), to exploit key genome regions during breeding. Twenty-four cultivars(including SH527, its six progenitors and 17 derived cultivars) were collected and analyzed with high-density single nucleotide polymorphism(SNP) array. Scanning all these cultivars with genome-wide SNP data indicated the unique contributions of progenitors to the SH527 genome and identified the key genomic regions of SH527 conserved within all its derivatives. These findings were further supported by known rice yield-related genes or unknown QTLs identified by genome-wide association study. This study reveals several key regions for SH527 and provides insights into hybrid rice breeding.展开更多
目的调查沈阳地区围产期孕妇生殖道B族链球菌(group B streptococcus,GBS)定植率和感染高危因素及对母婴结局的影响,以便预防和控制围产期妇女GBS感染,优化母婴结局。方法对2017年9—11月在医院作孕期检查的31~40周孕晚期孕妇691例取...目的调查沈阳地区围产期孕妇生殖道B族链球菌(group B streptococcus,GBS)定植率和感染高危因素及对母婴结局的影响,以便预防和控制围产期妇女GBS感染,优化母婴结局。方法对2017年9—11月在医院作孕期检查的31~40周孕晚期孕妇691例取阴道拭子及直肠拭子进行GBS培养、分离鉴定,分析GBS定植率;采用卡方检验进行GBS感染的单因素分析,采用多因素二元Logistic回归进行GBS感染的高危因素分析;对比两组孕妇及新生儿结局。结果沈阳地区孕晚期孕妇生殖道GBS定植率为7.67%(53/691),其中阴道试子阳性率为4.63%(32/691),直肠试子阳性率为6.22%(43/691);孕妇GBS感染的危险因素显示,在教育程度、生产史、分娩方式、甲状腺异常、妊娠期高血压、妊娠期贫血和妊娠期糖尿病,组间差异均无统计学意义(P>0.05);孕妇GBS感染危险因素,年龄、体质量、流产史和生殖道感染,组间比较,差异均有统计学意义(P<0.05);经多因素二元Logistic回归分析结果显示,年龄、体重、流产史和生殖道感染为影响GBS感染发生的独立危险因素,两组比较差异均有统计学意义(P<0.05);感染组孕妇胎膜早破、早产发生率高于对照组,经比较差异有统计学意义(P<0.05);产后出血发生率经比较差异无统计学意义(χ2=0.624,P>0.05);感染组新生儿胎儿窘迫、绒毛膜羊膜炎、新生儿黄疸发生率高于对照组,经比较差异有统计学意义(P<0.05)。结论沈阳市孕妇生殖道GBS定植率较高,建议对孕晚期孕妇开展GBS常规筛查。年龄、体重、流产史和生殖道感染为GBS感染发生的独立危险因素,有必要对本地区的围产期孕妇进行健康宣教,减少GBS感染的发生,进而改善母婴结局。展开更多
文摘In this study,the morphology and ultrastructure of the compound eye of L.lewisii were investigated using scanning electron microscopy(SEM),transmission electron microscopy(TEM),microcomputed tomography(μCT),and 3D reconstruction.The compound eye of L.lewisii was of the apposition type,with an average of 121.88±7.64 ommatidia in males and 119.00±4.71 ommatidia in females.Each ommatidium was composed of a biconvex cornea,an acone consisting of four cone cells,eight retinular cells along with the rhabdom,two primary pigment cells,and numerous secondary pigment cells.The open type of rhabdom in L.lewisii consists of six peripheral rhabdomeres contributed by the six peripheral retinular cells(R1~R6)and two vertically attached central rhabdomeres contributed by R7 and R8 respectively.The orientation of microvilli suggested a weak sensitivity to polarized light perception.
基金Supported by the National Natural Science Foundation of China(11501279,11501171,11671188,and11401604)the Young Backbone Teachers of Luoyang Normal University(2018XJGGJS-10)Henan Colleges(2015GGJS-193)
文摘This paper studies online scheduling of jobs with kind release times on a single machine. Here "kind release time" means that in online setting, no jobs can be released when the machine is busy. Each job J has a kind release time r(J) ≥ 0, a processing time p(J) > 0 and a deadline d(J) > 0. The goal is to determine a schedule which maximizes total processing time( p(J)E(J)) or total number( E(J)) of the accepted jobs. For the first objective function p(J)E(J), we first present a lower bound 2(1/2), and then provide an online algorithm LEJ with a competitive ratio of 3. This is the first deterministic algorithm for the problem with a constant competitive ratio. When p(J) ∈ {1, k}, k > 1 is a real number, we first present a lower bound min{(1 + k)/k, 2 k/(1 + k)}, and then we show that LEJ has a competitive ratio of1 + k/k. In particular, when all the k length jobs have tight deadlines, we first present a lower bound max{4/(2 + k), 1}(for p(J)E(J)) and 4/3(for E(J)). Then we prove that LEJ is k/k-competitive for p(J)E(J) and we provide an online algorithm H with a competitive ratio of 2 k/( k + 1) for the second objective function E(J).
基金supported by the Sichuan Science and Technology Support Project, China (2016NZ0103)the National Natural Science Foundation of China (91435102 and 31570004)+1 种基金the Sichuan Provincial Founding for Distinguished Young Scholars, China (2015JQ0048)the Open Research Fund of State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, China (2016KF10)。
文摘Hybrid rice significantly contributes to the food supply worldwide. Backbone parents play important roles in elite hybrid rice breeding systems. In this study, we performed pedigree-based analysis of the elite backbone parent rice variety, namely, Shuhui 527(SH527, Oryza sativa), to exploit key genome regions during breeding. Twenty-four cultivars(including SH527, its six progenitors and 17 derived cultivars) were collected and analyzed with high-density single nucleotide polymorphism(SNP) array. Scanning all these cultivars with genome-wide SNP data indicated the unique contributions of progenitors to the SH527 genome and identified the key genomic regions of SH527 conserved within all its derivatives. These findings were further supported by known rice yield-related genes or unknown QTLs identified by genome-wide association study. This study reveals several key regions for SH527 and provides insights into hybrid rice breeding.
文摘目的调查沈阳地区围产期孕妇生殖道B族链球菌(group B streptococcus,GBS)定植率和感染高危因素及对母婴结局的影响,以便预防和控制围产期妇女GBS感染,优化母婴结局。方法对2017年9—11月在医院作孕期检查的31~40周孕晚期孕妇691例取阴道拭子及直肠拭子进行GBS培养、分离鉴定,分析GBS定植率;采用卡方检验进行GBS感染的单因素分析,采用多因素二元Logistic回归进行GBS感染的高危因素分析;对比两组孕妇及新生儿结局。结果沈阳地区孕晚期孕妇生殖道GBS定植率为7.67%(53/691),其中阴道试子阳性率为4.63%(32/691),直肠试子阳性率为6.22%(43/691);孕妇GBS感染的危险因素显示,在教育程度、生产史、分娩方式、甲状腺异常、妊娠期高血压、妊娠期贫血和妊娠期糖尿病,组间差异均无统计学意义(P>0.05);孕妇GBS感染危险因素,年龄、体质量、流产史和生殖道感染,组间比较,差异均有统计学意义(P<0.05);经多因素二元Logistic回归分析结果显示,年龄、体重、流产史和生殖道感染为影响GBS感染发生的独立危险因素,两组比较差异均有统计学意义(P<0.05);感染组孕妇胎膜早破、早产发生率高于对照组,经比较差异有统计学意义(P<0.05);产后出血发生率经比较差异无统计学意义(χ2=0.624,P>0.05);感染组新生儿胎儿窘迫、绒毛膜羊膜炎、新生儿黄疸发生率高于对照组,经比较差异有统计学意义(P<0.05)。结论沈阳市孕妇生殖道GBS定植率较高,建议对孕晚期孕妇开展GBS常规筛查。年龄、体重、流产史和生殖道感染为GBS感染发生的独立危险因素,有必要对本地区的围产期孕妇进行健康宣教,减少GBS感染的发生,进而改善母婴结局。