Comment on "Fossilized nuclei and germination structures identify Ediacaran 'animal embryos' as encysting protists"

On the basis of putative nuclei and endospores, Huldtgren et al. (Reports, 23 December 2011, p. 1696) propose that embryo-like Doushantuo microfossils are nonmetazoan holozoans akin to mesomycetozoeans. However, both size and preservation preclude interpretation of internal structures as nuclei. Moreover, the authors may have conflated two different populations; some specimens display a pseudoparenchymatous organization incompatible with a mesomycetozoean comparison.     

Costs and the diversification of exaggerated animal structures

Sexual selection can favor production of extravagant ornaments and weapons in the contest for access to the opposite sex. Existing explanations for the diversity of sexually selected structures focus on reproductive benefits conferred by particular ornament or weapon morphologies. Here, I show that costs of weapon production also may drive patterns of weapon evolution. In beetles, production of horns reduces the size of neighboring morphological structures (antennae, eyes, or wings, depending on the location of the horns), and these tradeoffs reveal unexpected functional associations between ecology and horn morphology. This study illustrates a critical but overlooked role of costs in sexual selection and has implications for understanding the evolution of animal morphology.     

Cryopreservation of farm animal gametes and embryos: recent updates and progress

Cryopreservation has undergone tremendous advances and is widely used in animal production based on decades of study of cellular permeability, freezability and empirical generalization. Several improvement are particularly important: the cryopreservation protocol has been continuously refined over the years to achieve greater reproductive performance; cryoprotective agents are more effective and less toxic than previously; there has been significant innovation in advanced cryopreservation systems and carriers. Despite this, there are still problems that urgently require practical solutions, such as remedies for cryodamage and encouraging the use of frozen–thawed porcine sperm in pig production.     

动物组织学与胚胎学CAI课件的制作

动物组织学与胚胎学是动物医学和动物科学专业的一门必修专业基础课,是一门典型的形态学科.结构微细,内容抽象,难以理解等特点.为了适应新世纪教学内容对教学方法改革的要求,我们结合动物组织学与胚胎学教学实际,利用Authorware6.0制作出动物组织学与胚胎学教学用多媒体CAI课件.文章着重介绍了动物组织学与胚胎学的特点,CAI课件的制作过程、注意事项和使用效果等内容.     

Structural organization of nuclei and nucleoli of wheat shoot and root meristem during germination under alkaline pH conditions

The state of the nuclear compartment of winter wheat shoot and root meristem during germination under high pH value conditions is analyzed. An increase in the number of amoeboid nucleoli having protuberances, disturbance of chromatin compaction, and occurrence of nuclear bodies of unknown etiology in apical meristem are noted.     

甘蔗“健康种子”发芽率及生长影响因素分析

[目的]分析不同品种、种衣剂及保存天数对甘蔗“健康种子”发芽率及生长发育的影响,为甘蔗“健康种子”技术的研究和应用提供理论支持.[方法]采用温室沙培试验,测定不同甘蔗品种、种衣剂及保存天数处理下甘蔗“健康种子”的发芽率、株高及假茎粗.[结果]甘蔗“健康种子”的发芽率、株高及假茎粗存在明显的基因型差异,4个品种中,GT28的发芽率、株高和假茎粗均最高,分别为69.5％、13.7 cm和4.92 mm.不同种衣剂包衣处理可显著提高甘蔗“健康种子”的发芽率,但对株高和假茎粗的影响不明显,其中扑力猛包衣处理的甘蔗“健康种子”发芽率最高,株高较高,假茎较粗;高巧包衣处理的甘蔗“健康种子”发芽率最低,株高较矮,假茎较细.甘蔗“健康种子”发芽率随保存时间的延长而下降,保存2d的种子发芽率最高,达83.6％;保存10d时,发芽率降至50.0％以下.[结论]不同甘蔗品种单芽的发芽率具有明显的基因型差异,适当的种衣剂包衣处理可提高甘蔗“健康种子”的发芽率并促进其生长,且甘蔗“健康种子”的发芽率随保存时间的延长而降低.     

茶树幼胚培养萌发率与再生途径影响因素研究

从激素浓度与组合、基本培养基和蔗糖浓度等几个方面进行了茶树幼胚培养中萌发率和再生途径的影响因素研究。试验结果表明，茶树幼胚的萌发需要有一定量的生长素的刺激作用，但较强烈的细胞分裂素的作用对茶树幼胚的萌发有抑制作用；所使用的激素种类对于胚的再生途径有较大的影响，在MS＋KT2．0＋IBA0．1＋GA31．0mg／L培养基上，80％以上的幼胚可以继续发育成熟并萌发成苗；而高糖浓度则会诱导产生较多的胚性愈伤组织并从而导致不定胚的形成。     

Comment on "Gene regulatory networks and the evolution of animal body plans"

Davidson and Erwin (Reviews, 10 February 2006, p. 796) argued that known microevolutionary processes cannot explain the evolution of large differences in development that characterize phyla. Instead, they proposed that phyla arise from novel evolutionary processes involving large mutations acting on conserved core pathways of development. I question some of their assumptions and show that natural selection adequately explains the origin of new phyla.     

光合细菌PSB-1对几种蔬菜种子发芽及成苗的作用

在几种蔬菜上进行了喷施光合细菌PSB-1菌液的试验，结果表明，辣椒、茄子、番茄种子经PSB发酵液处理后，可提高其发芽率、发芽势与成苗率。     

"蜀龙"水稻种衣剂的安全性和对水稻发芽、出苗、生长的影响

采用四川省农科院植物保护研究所研制的水稻种衣剂对60只大鼠(雄性和雌性各30只),分别进行SD大鼠经口和急性经皮毒性试验;用白色家兔4只进行皮肤刺激性和眼粘膜刺激性试验。将8种不同配方“蜀农”水稻种衣剂与稻种分别按1：25的比例包衣,进行室内发芽势和发芽率测定;田间小区出苗、生长测定。结果表明：水稻种衣剂对SD大鼠的急性经口和经皮毒性均属低毒类。对家兔皮肤和家鬼眼帖膜无刺激性。种衣剂按常规方法浸种、催芽,对水稻种子安全;并且能够显著提高种子的出苗率、增加秧苗单株分蘖数和促进秧苗生长。     

转基因动植物生物反应器研究进展及应用现状

转基因动植物作为生物反应器,有完善的真核表达系统,可以为多种外源蛋白提供正确的翻译后修饰,表达具有生物活性的外源蛋白,可以应用于人或动物的疾病治疗及预防,因其具有成本低、产出高、产品珍贵且需求高的特点而具有广阔的商业前景。目前,转基因动植物生物反应器研究领域已经取得多项成果与突破,以此生产的蛋白制品也有部分被权威机构批准上市应用,还有许多未上市的研究成果已经进入临床试验阶段,为产业化发展做准备。动植物生物反应器已成为重组药用蛋白生产的新趋势。综述了转基因植物和转基因动物作为生物反应器生产重组蛋白的研究进展及应用现状,介绍了生物反应器类型、生产的蛋白种类、已获批应用的动植物生物反应器,讨论了利用动植物生物反应器生产外源蛋白的意义及存在的问题,对其研究及应用前景进行展望。     

Micromanipulation in control and handling of Zygiella x-notata as an experimental animal

The spider Zygiella x-notata may be brought under direct control analagous to that of the common laboratory animals for an important group of experimental investigations on the nerve, muscle, or secretion of digestive glands. Without anesthetics, chilling, or damage the animal can be fixed for prolonged periods and microinstruments (which include feeding pipettes), positioned by a standard micromanipulator.     

粳稻品系“超2-10”幼胚在不同温度下的诱导和再生研究

以梗型高产水稻品系"超2-10"幼胚为外植体,在26、36、38℃和40℃下进行愈伤组织诱导和继代培养,并完成整个再生过程.结果显示,"超2-10"水稻幼胚在26、36、38℃和40℃环境中均能成功诱导愈伤组织,诱导率达到90%以上,4种温度条件下幼胚愈伤组织诱导率无显著差异;26℃和36℃环境诱导和继代培养的愈伤组织都能够正常生长、分化和再生,而38℃和40℃环境诱导和继代培养的愈伤组织能够生长,但分化和再生都受到影响;尽管36℃环境生长的愈伤组织在继代培养中重量增幅明显低于26℃继代培养的愈伤组织,但36℃诱导和继代培养的愈伤组织再生率明显高于26℃环境培养的愈伤组织.再生率提高40.81%.     

上德若谷上善若水--老子《道德经》之道德修养标准

老子的《道德经》可是各个方面道德修养的经典大全,老子提出的在个人为人处世方面也就是自身品德修养方面的道德标准完全不同于我们平常说的“仁、义、礼、智、信”,它的核心内容是:有慈爱心,节减寡欲,知足长乐,以天、地、水的品德去做事情,消除企图心、名利心。老子的上述道德修标准对今天提高我们每个人自身修养仍具有现实意义。     

广优772作菜后稻的种植表现及其栽培技术

介绍广优772在建瓯市作菜后稻的种植表现,并从育秧、移栽、肥水管理、病虫害防治等方面总结其高产栽培技术。     

二氢异喹啉抗菌物质对植物种子萌发及幼苗生长的影响

【目的】研究2-芳基-6,7-亚甲二氧基-3,4-二氢异喹啉盐类化合物对植物种子发芽和幼苗生长的安全性,为此类化合物作为新型植物抗菌药物的开发应用提供理论依据。【方法】将糜子和油菜种子在14种2-芳基-6,7-亚甲二氧基-3,4-二氢异喹啉盐类化合物(Z-1~Z-14)溶液中浸种20h后,均匀点播于含无离子水的培养皿中,在设定条件下进行培养,测定种子的发芽率、根长、茎长、总鲜质量、总干质量和相对含水量。【结果】在100μg/mL测试质量浓度下,化合物Z-1、Z-3、Z-12、Z-13和Z-14对1种或2种作物的个别生长指标有显著的抑制作用,化合物Z-2、Z-4、Z-9和Z-10能够显著促进糜子根和茎的生长,同时对糜子的发芽率和幼苗的相对含水量没有显著影响;其他供试化合物对糜子和油菜的种子发芽和幼苗生长均无显著影响。【结论】除化合物Z-1、Z-3、Z-12、Z-13和Z-14外,其他供试的化合物在质量浓度≤100μg/mL时,对受试作物的种子萌发和幼苗生长均不会产生不良影响,部分化合物还具有促进作物根茎生长的效果,具备进一步评测后作为作物抗菌剂开发的可能。     

岳优9113作晚稻种植优质高产栽培技术

岳优9113在松溪县作双晚种植,表现出高产、优质、矮秆、抗倒、分蘖力强、生育期短、剑叶短小、适应性广、较易落粒等特点.栽培上应掌握适时稀播种育壮秧,秧龄控制在25 d以内,合理插植和肥水管理,注意病虫害的防治.     

Isospin in Nuclei: Isospin has been reborn as an important and useful quantum number for all nuclei

The major feature of isospin in nuclei that I have discussed here is its application to all nuclei. The rebirth of this quantum number in nuclear physics occurred in the early 1960's and was initiated almost entirely by the important work of Anderson et al. (4) and Fox et al. (5). There is still great interest in the use of isospin in its fullest sense as predicted by Wigner (3), and indeed isospin concepts have been largely responsible for demonstrating that nuclei in the doubly "magic number" region of (208)Pb are remarkably in agreement with shell model theory. The early experiments have also initiated a whole new set of more sophisticated experiments (some of which I have briefly alluded to above) which promise to keep many physicists busy for a long time to come. A particularly interesting series of experiments are those being performed (15) at Duke University with high-resolution proton beams. This work shows the highly detailed nature of analogue resonances, that is, as coherent superpositions of many complicated compound states yielding a beautifully modulated wave train, the modulation being observed only in conventional experiments with poor-resolution proton beams. Similarly, nuclear theorists have been led to vastly improve their interpretation of, and computational techniques for, both nuclear reactions and nuclear structure in order to meet the more stringent tests provided by such experiments. Perhaps a lesson can be learned from the historical development of the isospin concept. In the past the belief that T . T would not significantly commute with the dynamical Hamiltonian so that isospin would not be conserved sufficiently well enough certainly delayed the nuclear travels of isospin into the realm of heavy nuclei. Hopefully the same mistake will not occur in the future for other approximate symmetries of nature.     

“重农轻牧”思想与中国北方草地资源的利用

从分析中国北方草地资源利用中存在的问题入手,引出了这类问题产生的深层次文化根源—“重农轻牧”思想。并指出“重农轻牧”思想作为中国农耕文化的核心部分,长期以来通过影响国家的土地利用政策导向、民众的思想意识以及土地利用行为而导致中国北方草原地区严重的生态环境问题的产生。     

分子标记在动植物检验检疫与GMO产品检测中的应用

介绍了几种常用的分子标记技术,综述了分子标记技术在动植物、食品等检验检疫与转基因生物及其产品外源基因检测中的应用,展望了分子标记技术在检验检疫中应用的信息化、网络化前景.