Determinants, models and evaluation of multi-level ontogenetic development

The article presents an outline of multilevel phenotypic development which describes the course of ontogenetic development of a population and an individual. It is pointed out that this development does not take place in a non-standard way. Deviations and fluctuations which are normal phenomena in biological development take place. The developmental regularities, presented in the models of development and described by means of theorems, characterize the main paths of ontogenesis of a population and an individual. The method of evaluation of the advancement of ontogenetic development is also given. This method is a practical application of the proposed theoretical concept.     

Timekeeping by frog embryos, in normal development and after heat shock

(1) Timekeeping refers to the uniformity of development in time. The precision of timekeeping is measured by the extent to which embryos, within an initially synchronous population, come to diverge in the course of their development. (2) Divergence is measured as the variation in the stage of development reached between embryos allowed to develop for a fixed period of time. The lower the variation the better the timekeeping. (3) Divergence among frog embryos that started development at the same time is hardly measurable after approx. 100 h of development. This striking uniformity indicates good timekeeping. (4) Timekeeping is not impaired among the survivors following heat shocks that retard development and disturb and curtail morphogenesis. (5) The immediate effect of heat shock is a stoppage of development, the duration of which is the same for all embryos in the same treatment batch. The embryos react to heat shock by rescheduling their development with the interpolation of a rest, the duration of which is controlled to the same precision as normal development. The postponement of development, without impairment of timekeeping, implies dis-engagement of the processes of morphogenesis from, and their subsequent re-engagement with, an enduring rate-determining activity unaffected by heat shock. (6) We have searched for embryos whose rate of development was disturbed by heat shock to run slower or faster than the norm. We have found none. It seems that the (temperature-compensated) rate of development is invariant up to the moment of failure, or a change is immediately lethal.     

主体功能区视角下的碳排放核算——以广东省为例

区域碳排放核算是当前全球气候变化与碳排放研究的核心内容之一。中国于2010年出台《全国主体功能区规划》,主体功能区是以区域开发程度、资源环境基础和未来开发潜力为依据,县域为基本单位的区域规划方案,这为区域碳排放核算和配额分配提供了全新的视角。鉴于县域的能源数据不够完善,基于经济、人口、省级能耗量等数据构建了适用于主体功能区划分的碳排放核算方法,并确保各主体功能区的碳排放总量和分部门碳排放量都与该省的总碳排放量和分部门的一一对应相等。以中国广东省为案例,对其四类主体功能区在2005—2015年间的碳排放情况进行核算分析。研究发现:四类主体功能区的碳排放总量与经济总量呈现高度正相关性;四类地区中碳排放量从大到小依次为优化、重点、农产品、生态开发区。碳排放强度最大的为生态开发区,其次是重点开发区,农产品开发区和优化开发区。重点开发区和优化开发区的碳排放占全省比值达86%,都应作为未来节能减排措施的最主要的作用对象,需加快产业结构升级,扩大新能源技术的应用。农产品开发区和生态开发区应加快发展循环农业,有机低碳农业生态环境友好型产业。     

林业资源型城市生态-经济-社会协调发展的定量测度——以黑龙江省伊春市为例

把握城市独特的生态-经济-社会系统协调优化特性是实现林业资源型城市可持续发展的重要前提。研究从生态、经济、社会3个维度构建了林业资源型城市复合系统的测度评价指标体系,应用熵值法、耦合协调度模型,采用2005-2018年时段生态、经济、社会数据,对伊春协调发展状况进行实证测度评价,运用障碍度模型分析影响系统协调发展的主要因素,采用GM （1,1）灰色预测模型进行发展预测。结果表明：（1）综合发展指数呈上升态势,促进生态-经济-社会综合发展的主要动能历经了从生态到经济,再到生态为主要动力的发展过程,三个子系统发展水平呈趋同态势,推动三维系统的均衡协同是未来发展的重要方向;（2）三维系统耦合度稳定在较高水平,系统间相互依赖、相互作用程度较高,协调度呈波动上升,实现了由勉强协调、经济滞后发展向良好协调、同步发展的转变,协调状态趋向良好;（3）三维系统中社会子系统对协调发展的障碍度最大;人口自然增长率、建成区绿化覆盖率、GDP增长率、第三产业就业人数比重4个指标是制约近期协调发展的主要障碍因子;（4）2019-2030年,生态、经济、社会子系统发展指数及协调度的预测值均呈上升态势,生态-经济-社会复合系统将向更高级的协调发展状态演进,经济发展将再次成为促进生态-经济-社会综合发展的主要动力;加强生态建设,引领生态创新,大力发展生态经济,提高社会发展水平,着力降低障碍因子对协调发展的阻力作用,实现生态-经济-社会的联动健康发展是伊春未来重要的努力方向。     

福建省生态环境与高质量发展耦合关系及驱动机制

研究生态环境与高质量发展耦合关系时空演变及驱动机制,对实现可持续发展、构建生态文明体系和建设美丽中国具有重要意义。综合构建了生态环境-高质量发展指标体系,运用耦合协调度模型、空间马尔科夫链和BP神经网络-地理加权回归组合模型,系统探讨2005-2020年福建省生态环境与高质量发展耦合关系的时空演变及驱动机制。结果表明：（1）研究期间,福建省生态环境指数整体稳定,而高质量发展指数呈现先降低后上升的变化趋势,二者在空间上的组合关系整体呈现错位特征。（2）福建省县域生态环境与高质量发展指标之间的耦合关系呈先降低后上升的趋势,且呈现明显的空间异质性。（3）协调发展和绿色发展是驱动生态环境质量提高的关键因素,其影响程度呈"圈层式"空间分布特征。     

Ultrastructure and Carotenoid Composition of Chromoplasts of the Sepals of Strelitzia reginae Aiton during Floral Development

Ontogenetic development of chromoplasts from the coloured outerperianth segments of the flower of Strelitzia reginae was examinedwith an electron microscope. The plastids evolved through fivestages, namely, colourless leucoplasts, chloroplasts, pale yellow,deep yellow and orange chromoplasts. The relationship betweenplastid ultrastructure and carotenoid composition is discussed.The development of fibrils from osmiophilic globules is shownto occur in chromoplasts which contained only small amountsof chlorophyll at an early stage of development. Regular lattices of globular subunits were found which showeda hexagonal or rhomboidal pattern and which are probably proteinin nature. The sudden disappearance of these crystals just beforefibrils form, and the complete absence of starch from all stagesof plastid development, suggests that these crystals are a formof energy storage.     

城市可持续发展评价方法及其应用

城市是现代化建设的主要载体,是国家实施科教兴国和可持续发展战略的主要基地。城市将各种社会的、经济的、环境的、文化的因素与冲突融为一体,形成一类社会-经济-自然复合生态系统。如何实现城市的可持续发展,是当今世界研究的重要课题之一。城市可持续发展的评价指标和方法是衡量城市生态规划、建设、管理成效的主要依据。以山东济宁市为例,建立了济宁市可持续发展的指标体系,包括经济发展、生态建设、环境保护和社会进步4类45项指标。采用全排列多边形综合图示法评价城市在各个不同时段的建设成效。研究结果表明,济宁市可持续发展综合指数2004年为0.24,处于Ⅳ级水平,可持续发展能力较差;2006年达到0.45,处于Ⅲ级水平,可持续发展能力一般;2010年达到0.62,进入Ⅱ级水平,可持续发展能力较好;2020年达到0.84,进入I级水平,可持续发展能力优良。评价指标全面,方法直观明了,反映了整体大于或者小于部分之和的系统整合原理,评价结果符合实际,可为城市可持续发展提供参考。     

植物胚乳发育的表观遗传学调控

被子植物的种子发育从双受精开始, 产生二倍体的胚和三倍体的胚乳。在种子发育和萌发过程中, 胚乳向胚组织提供营养物质, 因此胚乳对胚和种子的正常生长发育至关重要。开花植物发生基因组印迹的主要器官是胚乳。印迹基因的表达受表观遗传学机制的调控, 包括DNA甲基化和组蛋白H3K27甲基化修饰以及依赖于PolIV的siRNAs (p4-siRNAs)调控。基因组印迹的表观遗传学调控对胚乳的正常发育和种子育性具有不可或缺的重要作用。最新研究显示, 胚乳的整个基因组DNA甲基化水平降低, 而且去甲基化作用可能源于雌配子体的中央细胞。该文综述了种子发育的表观遗传学调控机制, 包括基因组印迹机制以及胚乳基因组DNA甲基化变化研究的最新进展。     

RELATION BETWEEN METAMORPHOSIS AND OTHER DEVELOPMENTAL PHENOMENA IN AMPHIBIANS

1. The difference in time existing between the first shedding of the skin and the reduction of the gills to mere stubs without fringes is constant and unchangeable, which indicates that the fundamental cause for both is a common one. 2. This common cause is the action of iodine, and consequently both phenomena constitute, or at least are part of, the metamorphosis of the salamanders. 3. The development of the adult skin coloration and of the legs may take place either before or after metamorphosis. Iodine cannot enforce either of these phenomena. 4. The same is true of the development of the sex organs. 5. Development of the tongue and palatal teeth can be checked even in animals in which metamorphosis takes place. 6. Consequently development of the skin coloration, as well as development of the legs, sex organs, tongue, and palatal teeth are all caused by substances not identical with the substances causing metamorphosis and, since they are also all independent of each other in their development, it is probable that special chemical mechanisms exist for the development of each one of these six groups of organs. 7. This assumption is also supported by the fact that the order of development in several of these organ pairs can be changed by a difference in temperature, which would indicate that the development of each of these groups of organs is caused by chemical reactions with different temperature coefficients. 8. That the germ cells can develop in amphibians either before or after metamorphosis does not mean that the germ plasma is opposed as a unit to the somatic plasma, since other organs which are believed to be part of the somatic plasma behave in this respect like the germ cells. 9. The noteworthy feature of the amphibian metamorphosis is that instead of being controlled and kept in harmony by the organic individual the development of at least six groups of organs is controlled separately by the action of probably six different chemical mechanisms, each of which can be stopped or enforced independently either by directly supplying the substances required or by causing an increased formation within the body by suitable temperatures.     

Coelomogenesis during the abbreviated development of the echinoid Heliocidaris erythrogramma and the developmental origin of the echinoderm pentameral body plan

The development of the coeloms is described in an echinoid with an abbreviated larval development and shows the early morphogenesis of the coeloms of the adult stage. The development is described from images obtained by laser scanning confocal microscopy. The development in Heliocidaris erythrogramma is asymmetric with a larger left coelom forming on the larval-left side and a smaller right coelom forming on the larval-right side. The right coelom forms after the development of the left coelom is well advanced. The hydrocoele forms from the anterior part of the left coelom. The five lobes of the hydrocoele from which the pentamery of the adult derives take shape on the outer, distal wall of the anterior part of the left coelom. The hydrocoele separates from the more posterior part of the left coelom, which becomes the left posterior coelom. The lobes of the hydrocoele are named, based on the site of the connexion of the stone canal to the hydrocoele. The mouth is assumed to form by penetration through only the outer, distal wall of the hydrocoele and the ectoderm. Both larval and adult polarities are evident in this larva. A comparison with coelomogenesis in the asteroid Parvulastra exigua, which also has an abbreviated development, leads to predictions of homology between the echinoderm and chordate phyla that do not require the hypothesis of a dorsoventral inversion event in chordates.     

Integrating developmental biology into the undergraduate curriculum at the University of Bath,United Kingdom

The undergraduate curriculum for bioscience degrees at the University of Bath is outlined, and the place is described of the developmental biology components within it. In the first year, all students receive four lectures on animal development and four on plant development. In the second year, many choose substantial lecture and practical courses on animal development, which outline the early development of Xenopus, mouse and Drosophila. The third year is usually spent on placement, with a company or research institute, a few of which are developmental biology-based, and may also involve some distance learning. The fourth year is spent back in Bath. Students interested in developmental biology can opt for advanced courses covering vertebrate organogenesis, developmental neurobiology and plant development. There are also one-semester, final-year projects spent in the labs of faculty members, several of whom specialise in developmental biology and offer projects accordingly.     

多源空间数据整合视角下的城市开发强度研究

城市开发强度能直观表征人类活动强度,对指导城市规划与管理、促进城市可持续发展具有重要价值。采用社会-经济-生态系统耦合视角构建城市开发强度的多维测度体系,整合多源空间数据,测度了杭州市主城及3个副城的开发强度并揭示了其空间分布特征。结果表明,杭州城市开发强度由主城向副城呈波动降低,高强度开发过度集中于主城,主城的功能疏散有待加强;各副城开发强度不一,江南城与主城呈现跨江融合,临平城、下沙城空间上较为独立;各开发维度中,建筑强度、功能强度及效益强度热点区分布基本一致,环境响应高强度区则集聚于主副城交界处,表现出空间异质性。多维测度体系可较好表征城市开发强度,对城市规划及精细化管理具有一定的应用价值。     

林木花发育的基因调控

花发育是林木生长发育过程中的重要阶段。林木的花发育分为开花诱导、花的发端和花器官发育3个阶段,是由多种基因参与的十分复杂的调控过程。本文对林木在花发育过程中的基因调控进行了综述,并对林木花发育领域的研究前景进行了展望。     

Individual variability of development in laboratory-reared Temora stylifera copepodites: consequences for the population dynamics and interpretation in the scope of growth and development rules

By following individually the development of Temora styliferacopepodites from the same brood, we can explain the asymmetricalshape shown by the abundance curves of the successive stagesof a cohort when it is raised. The abundance peak correspondsto individuals which have an optimal development, while thetail-end, which gets bigger and bigger from one stage to another,is composed of individuals which could not stay in the headgroup These individuals never make up for their lateness, butmay stabilize it, thus coming back to a normal development rateDevelopment and growth rules are estimated from the best performingindividuals and thus represent the optimal potential characteristicsfor the growth and development of a population Under conditionswhich limit growth, the spreading of the abundance curves isstrongly expressed, and it becomes impossible to observe a peakof abundance in experiments This might explain why results fromliterature are sometimes contradictory concerning the growthof the same species under conditions which limit development.     

发育重演律与生物进化

发育重演律是生物个体发育的一般规律,该规律认为生物个体的发育是类囊胚不断形成和演化的过程,并认为生物进化亦是类囊胚不断形成和演化的过程.因类囊胚层级不断增加而导致的生物体结构复杂程度提高的演化为纵向进化,而不能提高生物体复杂程度的演化为横向演化,生物的纵向进化具有周期性.生物种系进化与个体发育之间具有严格的对应关系,一个物种经历的纵向进化的周期数与该物种所属个体完成发育所经历的细胞分化的周期数相等.     

中国地级区域高质量发展格局与影响因素

高质量发展战略对中国生态经济系统的运行提出了更高要求。当前对高质量发展的研究侧重经济子系统,对生态子系统和社会子系统的分析相对薄弱,且缺乏省级以下中微观尺度的分析。从经济质量、创新潜力、环境质量、生态安全、人民生活和城乡协调六个维度解析了高质量发展内涵,搜集了全国306个地级区域2018年的数据资料,构建地级区域高质量发展综合评价指标体系,定量测算了地级区域高质量发展指数,揭示了区域格局,考察了影响因素,识别了问题区域,并提出了发展质量提升策略。研究表明：(1)高质量发展指数存在明显的区域差异,东部地区和长江流域发展水平相对较高,东北地区和黄河流域发展水平相对较低。(2)经济质量、创新潜力和人民生活指数的均值相对较低,是高质量发展的薄弱环节。(3)高质量发展水平受到自然环境适宜性、城市等级和人口集聚、投资水平、交通区位、数字经济等因素的综合影响,且具有较强的空间溢出效应。(4)识别出8大类174个高质量发展的问题地市,分布在26个省区,在黄河流域和东北地区相对集中。最后,从制度建设、全国层面和具体区域层面探讨了高质量发展水平提升路径,可为制定区域发展战略和区域政策提供科学参考。     

林木花发育的基因调控

花发育是林木生长发育过程中的重要阶段。林木的花发育分为开花诱导、花的发端和花器官发育3个阶段, 是由多种基因参与的十分复杂的调控过程。本文对林木在花发育过程中的基因调控进行了综述, 并对林木花发育领域的研究前景进行了展望。     

The whys and wherefores of gastrulation

Gastrulation is defined as the phase of morphogenetic movements lying between the blastula stage and the phylotypic (zootype) stage of development. The occurrence of gastrulation is universal among animals undergoing embryonic development from eggs, but there is considerable diversity in the types of movement observed. Gastrulation is also the stage at which the first very important developmental commitments are established, in particular those corresponding to the classical 'germ layers'. From an evolutionary point of view, animal development falls into three phases of which the first and last are variable and the middle, phylotypic, phase is most conservative. Gastrulation belongs to the early phase of development which is inherently variable because it is subject to selective forces operating on reproductive behaviour and life history, principally those controlling the number and size of eggs, and the means for embryonic nutrition.     

Ocular development and involution in the European cave salamander, Proteus anguinus laurenti.

The anatomy and development of the eye of Proteus anguinus are described. The relationships between organogenesis of the eye in embryos and larva and its involution in the young and the adult are discussed. The availability (in breeding cultures) of a significant number of Proteus embryos (which are normally rare) allowed experimental analysis of the effects of light, xenoplastic differentiation and thyroid hormones on the development of the eye. The results of this study suggest that development and involution of the eye of Proteus are controlled by genetic factors which are not greatly influenced by environment, and one can, therefore, consider the microphthalmy of Proteus as a relict characteristic which is the result of a specific development with disturbance of the normal ontogenic process.