Wing patterning genes of Nilaparvata lugens identification by transcriptome analysis, and their differential expression profile in wing pads between brachypterous and macropterous morphs

The brown planthopper, Nilaparvata lugens is an economically important pest on rice plants. This species produces macropterous and brachypterous morphs in response to environmental cues, which makes it very dififcult to control. The molecular basis of wing patterning in N. lugens is stil unknown. It is necessary to identify wing patterning genes of N. lugens, and also to clarify the expression differences of wing patterning genes between macropterous and brachypter-ous morphs. High-throughput deep sequencing of transcriptome of N. lugens wing pad yielded 116 744 580 raw reads and 113 042 700 clean reads. Al the reads were assembled into 55 963 unigenes with an average length of 804 bp. With the E-value cut-off of 1.0E–5,18 359 and 2 883 unigens had hits in NCBI-NR (NCBI non-redundant protein sequences) and NCBI-NT (NCBI nucleotide sequences) databases, respectively. A total of 16 502 unigenes were assigned to GO (gene ontology) classiifcation, 9 709 ungenes were grouped into 26 COG (cluster of orthologous groups of proteins) classiifcations, and 6 724 unigenes were assigned to different KEGG (Kyoto encyclopedia of genes and genomes) path-ways. In total, 56 unigenes which are homologous to wing patterning genes of Drosophila melanogaster or Tribolium castaneum were identiifed. Out of the 56 unigenes, 24 unigenes were selected, and their expression levels across the ifve nymphal stages between macropterous strain and brachypterous strain were examined by qRT-PCR. Two-way ANOVA analysis showed that development stage had signiifcant effects on the expression level of al the 24 genes (P<0.05). The expression levels of 8 genes (Nlen, Nlhh, Nlsal, NlAbd-A, Nlwg, Nlvg, Nlexd and NlUbx) were signiifcantly affected by wing morph. This is the ifrst transcriptome analysis of wing pads of hemimetabolous insect, N. lugens. The identiifed wing patterning genes would be useful resource for future exploration of molecular basis of wing development. The 8 differential y expressed wing patterning genes between macropterous strain and brachypterous strain would contribute to explain molecular mechanism of wing-morph differentiation in N. lugens.

A new monitoring index for ecological vulnerability and its application in the Yellow River Basin,China from 2000 to 2022

The ecological environment of the Yellow River Basin has become more fragile under the combined action of natural and manmade activities.However,the change mechanisms of ecological vulnerability in different sub-regions and periods vary,and the reasons for this variability are yet to be explained.Thus,in this study,we proposed a new remote sensing ecological vulnerability index by considering moisture,heat,greenness,dryness,land degradation,and social economy indicators and then analyzed and disclosed the spatial and temporal change patterns of ecological vulnerability of the Yellow River Basin,China from 2000 to 2022 and its driving mechanisms.The results showed that the newly proposed remote sensing ecological vulnerability index had a high accuracy,at 86.36%,which indicated a higher applicability in the Yellow River Basin.From 2000 to 2022,the average remote sensing ecological vulnerability index of the Yellow River Basin was 1.03,denoting moderate vulnerability level.The intensive vulnerability area was the most widely distributed,which was mostly located in the northern part of Shaanxi Province and the eastern part of Shanxi Province.From 2000 to 2022,the ecological vulnerability in the Yellow showed an overall stable trend,while that of the central and eastern regions showed an obvious trend of improvement.The gravity center of ecological vulnerability migrated southwest,indicating that the aggravation of ecological vulnerability in the southwestern regions was more severe than in the northeastern regions of the basin.The dominant single factor of changes in ecological vulnerability shifted from normalized difference vegetation index(NDVI)to temperature from 2000 to 2022,and the interaction factors shifted from temperature∩NDVI to temperature∩precipitation,which indicated that the global climate change exerted a more significant impact on regional ecosystems.The above results could provide decision support for the ecological protection and restoration of the Yellow River Basin.

The deterministic condition for the ground reaction force acting point on the combined knee valgus and tibial internal rotation moments in early phase of cutting maneuvers in female athletes

Background:Combined knee valgus and tibial internal rotation(VL+IR)moments have been shown to stress the anterior cruciate ligament(ACL)in several in vitro cadaveric studies.To utilize this knowledge for non-contact ACL injury prevention in sports,it is necessary to elucidate how the ground reaction force(GRF)acting point(center of pressure(CoP))in the stance foot produces combined knee VL+IR moments in risky maneuvers,such as cuttings.However,the effects of the GRF acting point on the development of the combined knee VL+IR moment in cutting are still unknown.Methods:We first established the deterministic mechanical condition that the CoP position relative to the tibial rotational axis differentiates the GRF vector’s directional probability for developing the combined knee VL+IR moment,and theoretically predicted that when the CoP is posterior to the tibial rotational axis,the GRF vector is more likely to produce the combined knee VL+IR moment than when the CoP is anterior to the tibial rotational axis.Then,we tested a stochastic aspect of our theory in a lab-controlled in vivo experiment.Fourteen females performed 60˚cutting under forefoot/rearfoot strike conditions(10 trials each).The positions of lower limb markers and GRF data were measured,and the knee moment due to GRF vector was calculated.The trials were divided into anterior-and posterior-CoP groups depending on the CoP position relative to the tibial rotational axis at each 10 ms interval from 0 to 100 ms after foot strike,and the occurrence rate of the combined knee VL+IR moment was compared between trial groups.Results:The posterior-CoP group showed significantly higher occurrence rates of the combined knee VL+IR moment(maximum of 82.8%)at every time point than those of the anterior-CoP trials,as theoretically predicted by the deterministic mechanical condition.Conclusion:The rearfoot strikes inducing the posterior CoP should be avoided to reduce the risk of non-contact ACL injury associated with the combined knee VL+IR stress.

Characteristics of a Laboratory Strain of Coleomegilla maculata with a Novel Heritable Wing Spot Pattern Trait

The lady beetle Coleomegilla maculata is a common New World insect that is naturally colored pink to red or orange with black spots on the forewings of the adult stage. Previous laboratory in-breeding resulted in selection for a strain lacking red pigment in the cuticle and eyes. An additional strain selected for a novel spotting pattern is described here. The inheritance of the new trait, “ten spotted” (10sp), was determined by classical crossing experiments. Inheritance of the trait was autosomal and exhibited incomplete dominance. Bionomic strain measurements were compared to the parental strains and were similar overall. Two expressed sequences from C. maculata that may be related to the new phenotype were compared to model insect genes encoding a melanin biosynthesis enzyme and a patterning transcription factor.

Stable Transition of Quadruped Rhythmic Motion Using the Tracking Differentiator

Since the quadruped robot possesses predominant environmental adaptability,it is expected to be employed in nature environments. In some situations,such as ice surface and tight space,the quadruped robot is required to lower the height of center of gravity( COG) to enhance the stability and maneuverability. To properly handle these situations,a quadruped controller based on the central pattern generator( CPG) model,the discrete tracking differentiator( TD) and proportional-derivative( PD) sub-controllers is presented. The CPG is used to generate basic rhythmic motion for the quadruped robot. The discrete TD is not only creatively employed to implement the transition between two different rhythmic medium values of the CPG which results in the adjustment of the height of COG of the quadruped robot,but also modified to control the transition duration which enables the quadruped robot to achieve the stable transition. Additionally,two specific PD sub-controllers are constructed to adjust the oscillation amplitude of the CPG,so as to avoid the severe deviation in the transverse direction during transition locomotion. Finally,the controller is validated on a quadruped model. A tunnel with variable height is built for the quadruped model to travel through. The simulation demonstrates the severe deviation without the PD sub-controllers,and the reduced deviation with the PD sub-controllers.

Landscape pattern change of a typical region in the Kubuqi Desert, Northwestern China

Spatial pattern analysis is the core component in landscape ecology research.We analyzed the landscape pattern and dynamic process of the Kubuqi Desert by using a typical region as a study area.This study area includes four towns;ShuLinZhao,WangAiZhao,BaiNiJing and JiGeSiTai.The area of cropland,fixed sand dune,woodland,residential area and wetland increased and centralized gradually,while the area of semi-fixed sand dune,drifting sand dune,meadow and washland decreased and dispersed gradually from 1987 to 2003.On the landscape level,the patch shape tended to be regular,and the landscape pattern tended to be simple,causing the fragmentation degree,heterogeneity and diversity of the landscape to decrease.Fixed sand dune.Semi-fixed sand dune,drifting sand dune,meadow and river flood plains were the five main export classes,and residential area,cropland and wetland were the three main import classes.The classes that had a relatively large total area and large average patch area had a smaller extent of gravity center migration,whereas the classes with small total area and small average patch area had a larger extent of gravity center migration;this is because the small patches are easily influenced by human activities or natural factors.In addition,the desertification area and desertification degree reduced gradually in the study area during the period from 1987 to 2003.

Balance control during gait initiation: State-of-the-art and research perspectives

It is well known that balance control is affected by aging, neurological and orthopedic conditions. Poor balance control during gait and postural maintenance are associated with disability, falls and increased mortality. Gait initiation-the transient period between the quiet standing posture and steady state walking-is a functional task that is classically used in the literature to investigate how the central nervous system(CNS) controls balance during a whole-body movement involving change in the base of support dimensions and center of mass progression. Understanding how the CNS in able-bodied subjects exerts this control during such a challenging task is a prerequisite to identifying motor disorders in populations with specific impairments of the postural system. It may also provide clinicians with objective measures to assess the efficiency of rehabilitation programs and better target interventions according to individual impairments. The present review thus proposes a state-of-the-art analysis on:(1) the balance control mechanisms in play during gait initiation in able bodied subjects and in the case of some frail populations; and(2) the biomechanical parameters used in the literature to quantify dynamic stability during gait initiation. Balance control mechanisms reviewed in this article included anticipatory postural adjustments, stance leg stiffness, foot placement, lateral ankle strategy, swing foot strike pattern and vertical center of mass braking. Based on this review, the following viewpoints were put forward:(1) dynamic stability during gait initiation may share a principle of homeostatic regulation similar to most physiological variables, where separate mechanisms need to be coordinated to ensure stabilization of vital variables, and consequently; and(2) rehabilitation interventions which focus on separate or isolated components of posture, balance, or gait may limit the effectiveness of current clinical practices.

Variation of hydraulic parameters with different wing of a T-shape spur dike in bend channels

In the present research,by using a numerical model,some analyses were performed on flows around a T-shape spur dike and a support structure located at its upstream under different wing to length ratios of T-shape spur dike in the order of 0.25,0.50,0.75 and 1.00.In order to verify numerical model,physical model data were used in presence of a single T shape spur dike.Results from numerical model are desirably in agreement with those of physical one because the regression between both data is 0.86 up to 0.92.In this research,all hydraulic parameters of flows,streamlines and dimensions of flow separation zones were studied in order to select the most practical model.Increased W/L results in 7%–12%increase in the length of flow separation zone and in 2%increase in the width of this zone compared to W/L=0.25.

A Survey of Human-centered Intelligent Robots:Issues and Challenges

Intelligent techniques foster the dissemination of new discoveries and novel technologies that advance the ability of robots to assist and support humans. The human-centered intelligent robot has become an important research field that spans all of the robot capabilities including navigation, intelligent control, pattern recognition and human-robot interaction. This paper focuses on the recent achievements and presents a survey of existing works on human-centered robots. Furthermore, we provide a comprehensive survey of the recent development of the human-centered intelligent robot and discuss the issues and challenges in the field.

Measurement on Camber Deformation of Wings of Free-flying Dragonflies and Beating-flying Dragonflies

The knowledge of wing orientation and deformation during flapping flight is necessary for a complete aerodynamic analysis, but to date those kinematic features have not been simultaneously quantified for free-flying insects. A projected comb-fringe (PCF) method has been developed for measuring spanwise camber changes on free-flying dragonflies and on beating-flying dragonflies through the course of a wingbeat, which bases on projecting a fringe pattern over the whole measurement area and then measuring the wing deformation from the distorted fringe pattern. Experimental results demonstrate substantial camber changes both along the wingspan and through the course of a wingbeat. The ratio of camber deformation to chord length for hind wing is up to 0.11 at 75% spanwise with a flapping angle of -0.66 degree for a free-flying dragonfly.

消费中心城市项目布局研究:分类、属性及途径

消费中心城市项目是消费中心聚集消费资源的重要载体,是服务消费者、引领消费潮流、发挥消费影响力的主要方式,项目成功与否是消费中心成败关键。对消费中心城市项目进行不同维度的分类,包括文化消费项目和物质消费项目、服务消费项目和商品消费项目、最终消费项目和中间消费项目、直接消费项目和间接消费项目、必要消费项目和非必要消费项目等,每种分类维度都有一定的分析意义。消费中心城市项目具有多种消费经济发展特性,包括消费的范围经济性、中心的规模经济性、文化消费的无限性和物质消费的有限性、消费的空间协调性、消费的系统制约性。在消费中心城市项目布局中,文化消费是关键,需要重点布局文化消费项目;物质消费带动潜力大,需要全面规划物质消费项目;空间资源紧张、空间成本高,需要通过中心紧密原则布局相关项目;消费系统配套性强,需要对消费中心城市项目进行超前和空间延展性布局;消费中心城市项目经济平衡作用显著,需要在欠发达地区做更多布局。

中国消费中心建设:现有格局、调整逻辑与发展路径

在制造业大国、生产中心背景下,我国又提出经济的消费转型,要建设消费大国,打造(国际)消费中心(城市)。当前,我国一些传统消费型城市经历了历史嬗变,后发的消费型城市更多立足于生产制造,一些偏远、基层城镇逐渐向消费中心转型,但大多数消费中心还未能实现专门性独立发展。从生产中心到消费中心有着很深的内在调整逻辑,包括经济增长动力改变,由供给推动向需求拉动转型;社会主要矛盾改变,更多化解发展不平衡不充分矛盾;经济水平提高,消费大发展的条件已经具备;资源和环境面临危机,需要以消费经济化解生产经济紧约束;国内外环境改变,消费中心担负经济突围重任。我国消费中心建设还存在诸多制约因素,如收入分配不合理,区域消费制约严重;过多生产作业加班,挤占生活消费空间;城市拥挤,消费流动不畅;公共设施落后,不能支撑消费大场景;更重生产,消费经济功能发挥有限;片面追求物质财富的拥有,全民生活消费筹划建设不够;内卷化竞争过于激烈,消费激情难以焕发;过多追名逐利,消费价值观有待重建。需要进行相关体制机制建设,政策调整方向包括适应生产劳动人工时间减少的趋势,增加消费时间;调整城市布局,畅通消费流;强化公共消费设施建设,营造消费大场景;调整收入分配,构建外向型消费结构;深化规律性认识,发挥好后工业时代消费对经济的主功能作用;引导消费,积极筹划消费蓝图;防范内卷化竞争,焕发全民消费激情;全面发展,重构生产价值和消费价值观体系。

“里和”与“外应”:气候变化下环湖地区的适应性治理

气候变化给青藏高原带来显著影响,更是对当地农牧民的生计造成冲击,研究当地气候变化影响及牧民应对策略,不仅是提高气候变化适应能力的起点,也是建立适应气候变化区域格局的重要支撑。基于2020和2023年对案例地Z村的两次实地调研,通过牧户问卷调查和深度访谈,按照适应性治理的三层特征,分析当地气候变化适应的成效与挑战。研究发现:面对降水和气温的变化、湖面扩大、植被变化和灾害影响,牧民积极采取多种办法来减少气候变化的影响,呈现较高的适应性与恢复力。这些适应行动的成功经验源于“里和”,包括人与人之间的合作以及人与自然间的和谐律动。但是“外应”不足仍是挑战,即案例地缺少必要的外部支持,不仅包括直接灾害救助,还包括对其适应能力可持续性的保护和应对潜在的草原生态变化。如果“外应”持续低迷,现有的适应能力终会耗尽。提出建立适应气候变化区域格局应遵循多中心治理的思路,将多个利益相关者联合起来,汇总不同地区气候变化应对的成功经验,形成多种知识的融合,才能形成对地方的有效“外应”,提高中国气候变化适应能力。

以学生为中心的食品酶学课程多维教学模式探析

以学生为中心的教学方式是引导学生全面发展、培养顺应时代需求的新工科人才的重要教学改革方向。该文针对食品酶学课程传统教学中存在的问题与教学要求,从知识构筑维度、课堂教学维度、课后提升维度和创新突破维度进行教学模式的探索与应用,实现对学生基础理论知识与创新实践能力的引导与培养,从课程教学方面为培养食品领域新工科人才提供助力。

新发展格局下构建区域性消费中心的提升策略研究

本文以区域性消费中心城市的提升策略为主题,从政策背景、基本理论、短板和问题、路径对策等几个方面进行研究,探索区域性消费中心城市建设中存在的问题。在新发展格局下,需要正确的政府引导,培育消费热点,优化消费环境,以品牌化建设打造城市消费优势。淮安市属于长三角的区域中心城市,靠近南京都市圈和苏锡常都市圈,地理位置可以说是占有优势的。淮安市需要加快中心城区崛起,提升整体竞争力,激发消费者前来消费的愿景。

加快构建辽宁“一体两翼”对外开放新格局

辽宁是东北亚开放的窗口和“一带一路”建设的重要节点,加快构建“一体两翼”对外开放新格局是辽宁深化改革、扩大开放、实现高质量发展和全面振兴全方位振兴的重要举措。从贸易开放、资金开放、技术开放、社会开放四个维度构建“一体两翼”对外开放效果评价体系,采用因子分析法对2021年我国内地31个省份对外开放度进行评价,结果显示:辽宁对外开放度在全国处于较低水平,外贸外资因子、教育文化因子和旅游因子得分显著低于广东、上海和浙江,是影响辽宁对外开放水平的主要因素。从外资外贸、教育文化、旅游方面的主因子视角和对接国际高标准规则优化营商环境,加强区域合作开放平台建设,完善国际合作交通网络等政策方面,提出加快构建辽宁“一体两翼”对外开放新格局的对策建议。

“双循环”新发展格局与上海国际科技创新中心建设新思路

科技创新是构建“双循环”新发展格局的关键支撑。构建“双循环”新发展格局,为上海深入推进科创中心建设、加快提升科创中心策源功能提供了重大战略机遇。研究表明,构建“双循环”新发展格局有利于上海科创中心更好地汇聚配置高端优质要素、化解科技重大风险挑战、加快提升科创策源功能,进而促进创新价值实现。在构建“双循环”新发展格局中,上海科创中心发展也面临一些瓶颈制约,主要表现为缺乏引领卓越创新的领军企业、企业创新能力亟须提升,缺乏支撑全面创新的制度供给、创新体制机制亟须完善,缺乏包容草根创新的社会环境、创新文化氛围亟须营造。进一步加强科创中心建设要有全新的思路,应牢牢把握“强基、健体、提质、增效”4个关键词。

1990—2020年滇中城市群耕地非农化时空变化特征及驱动机制

[目的]通过分析滇中城市群30年耕地非农化的演变路径、时空变化特征及驱动机制,为滇中城市群耕地资源的保护及精准管理提供理论依据。[方法]基于滇中城市群土地利用数据和统计年鉴数据,运用重心迁移模型、变化轨迹模型、空间自相关分析、主成分分析等方法揭示1990—2020年滇中城市群耕地非农化过程、空间分布特征及主要驱动因素。[结果](1)从时间上看,滇中城市群耕地非农化面积呈波动下降趋势,2000年前后由年均增加约6.88×10^(3)hm^(2)转变为年平均减少约2.66×10^(4)hm^(2),受政策、经济和城市化影响导致其变化最剧烈。从空间上看,耕地非农化集中分布于滇中城市群的中部、东部、东南部和东北部地区。(2)30年来,滇中城市群耕地非农化在空间分布上趋于均衡,区域间耕地非农化差异变小,空间格局趋于稳定。(3)滇中城市群耕地主要转出为林地和草地,少部分转化为建设用地,变化型耕地中有54.60%与草地相关,29.33%与林地相关,4.64%与建设用地相关,主要发生在滇中城市群的中部、北部、东南部和西北部的局部区域。(4)滇中城市群耕地非农化存在显著的空间聚集效应,以高—高聚集和低—低聚集为主,高—高聚集主要分布在中部、北部和东南部,低—低集聚主要分布在西北部、西部和西南部。(5)滇中城市群耕地非农化受社会经济和自然条件共同影响。社会经济中的农业人口、国有固定产投资和城市化率是耕地非农化最主要的驱动因素,影响系数分别为-0.18,0.11,0.10;而自然因素年平均降水量和年平均气温在耕地非农化空间分布和扩张过程起着关键性的作用,影响系数分别为0.17,-0.15。[结论]研究结果揭示30年来滇中城市群耕地非农化的时空变化特征、演变路径及驱动机制。对合理利用和保护耕地资源,保障云南省粮食安全具有重要作用,在一定程度上可为滇中城市群的耕地保护和耕地布局优化提供决策参考。

基于CFD的翼吊布局民机反推出流模式设计与验证

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