化学在农业院校遗传学教学中的渗透与思考

农业院校多数专业的课程设置里面, 化学是一类重要的基础课程, 而遗传学是核心的专业基础课。怎样将先修的化学知识向遗传学教学进行渗透, 从而在逻辑上体现专业基础课对基础课的“承上”功能, 是遗传学教师值得探讨的新问题。作者认为, 在农业院校的本科遗传学教学中, 应充分利用先修课程特别是化学的知识原理, 采用“渗透式”教学, 分析学科间知识点的内在联系, 加深学生对遗传学知识的认知和理解, 构建完整的知识体系, 提高学生分析能力、综合能力和逻辑思维能力, 探索综合竞争力强的复合型人才培养的教学模式。     

生态学本科人才多元化培养模式的构建与实践

随着高等教育的快速发展和社会对生态学本科专门人才的多元化需求, 深入思考和探索高等院校生态学本科专业人才培养目标, 建立“多元化创新型”人才培养模式, 搭建“以专业技能培养为核心”的课程体系和教学内容,完善“以综合能力培养为目标”的实践教学体系, 突出专业教学特色, 提高本科教育教学质量。     

普及生态文化 推进文化大省建设——代表省生态学会参加省十届人大二次会议旁听座谈会发言(提纲)

党十六大提出建设小康社会,广东省政府的《工作报告》提出建设经济强省和文化大省,与时俱进地反映了人类社会发展的要求。在政府《工作报告》中,多次提到生态方面的内容,如:我省“生态保护得到加强”,“建设生态文明城市”,“加快生态建设步伐”,“充分发挥山区和农村环境的生态屏障功能”,“统筹人与自然和谐发展,增强可持续发展能力”等等。可见,省委、省政府已把生态与环境的建设提到了重要议事日程。我认为,普及生态文化是和建设小康社会以及建设经济强省、文化大省分不开的。     

基于生态学视角的农科院校环境学科发展模式探讨

随着生态学的自然规律对社会科学发展的指导功能逐渐被发掘, 作为连接生态学与教育学桥梁的教育生态学应运而生。首先, 环境学科在结构和功能上具备明显的生态学特征。其次, 生态学定律对环境学科在社会服务功能、学科交叉、教学规模、教学侧重点、学生主观能动性等方面具有积极的启示。最后从生态学角度来看, 农科院校环境学科人才培养的发展模式应该立足于“三农”, 以解决“三农”“三废”问题为学科特色, 并促进学科交叉, 同时缩小教学规模以提高学生能动性; 此外, 应根据市场需求灵活调节教育模式以提高学生市场竞争力和就业率。     

高校大学生营养相关知识—态度—行为现况研究——以吉林某高校为例

目的：了解大学生营养相关知识、态度和行为状况,为改善学生营养状况提供科学依据。方法：采用分层随机抽样对吉林某高校1 075名在读大学生进行网络问卷调查,了解大学生营养相关知识—态度—行为现况。结果：“轻体力活动青年男性每天需要的能量”“高血压应该少吃盐”知晓率仅为254%、382%;有558%的学生认为“节食减肥会对健康产生危害”,而“愿意说服自己吃对健康有益,但不喜欢吃的食物”的比例仅为338%;过去1w内,“每天吃早餐”“每天喝牛奶或酸奶”的学生比例为393%、205%。结论：大学生的营养知识储备尚不完善,营养相关态度有待加强,膳食行为习惯有待改善。     

案例在遗传与优生教学中的应用

“遗传与优生”课程是遗传学与优生学相结合的一门交叉性学科, 是国内许多高校在教育教学改革中开设的一门通识课程。通过案例进行教学可以有效提升学生学习的积极性, 收到较好的教学效果。文章针对“遗传与优生”课程教学中应用案例进行教学所应注意的问题进行了讨论。     

植物成花调控的分子遗传学

对以拟南芥为主要对象进行的有关成花调控分子遗传学研究作了综述。该领域的研究已明确了对成花的调控没有单一的“成花万能基因”,而是有一群“成花时期基因”,并大致弄清了这些基因调控成花的模式。其结果是,成花调控途径具有多重性和冗长性,这些成花调控基因的参与量、基因之间的平衡都对成花起着重要的作用。     

我国高校遗传学教材的出版与使用现状的调查

利用国家图书馆“文津”搜索系统发现, 我国自恢复高考以来, 累计出版遗传学教材895部, 其中理论教材588部(65.7%)、实验教材122部(13.6%)、教学参考资料185部(20.7%)。这些教材中, 医学遗传学最多, 普通遗传学其次, 动植物微生物遗传学较少。对教材的名称、第一编(著)者和出版机构的分析发现, 名称为“医学遗传学”的教材有91部, 左伋教授编写了9部教材, 是编写教材最多的“第一编(著)者”, 科学出版社共出版了179部(占20%)教材, 是遗传学教材出版的主力军。利用问卷调查发现, 戴灼华等主编的《遗传学》(第二版)是目前使用最广泛的理论教材, 实验教材则多用自编讲义或教材。文章也对教材中存在的问题, 如更新周期长、配套落后、同名严重、遗传学故事写得太少、特色插图凤毛麟角、印刷页字数过满等进行了剖析, 并提出了解决途径。     

激发学生对遗传学实验学习兴趣的教学方法探索

通过增设研究性较强或由学生自主设计的实验项目, 采用生动有趣的案例式教学和问题式教学, 用“多元性”的教学理念设计实验教学环节, 结合综合性的教学手段, 有效激发了学生对遗传学实验的学习兴趣。     

“小饭桌”食品安全法律保障机制研究

“小饭桌”已遍布我国大陆城区,其首要功能是保证就餐学生的食品安全。当前“小饭桌”大多无证经营,环境卫生差、食品安全无保证,建议尽快出台全国层面专门的“学生小饭桌食品安全监督管理”立法,构建起“小饭桌”食品安全事前预防、事中监督管理及事后奖惩三大法律保障机制,并设计相应具体制度。必须对“小饭桌”经营者加强法制宣传教育、加强“小饭桌”食品安全政府日常监管、提高“小饭桌”学生及其家长的食品安全意识与法律维权能力以及强化“小饭桌”食品安全社会监督机制,以确保整套机制发挥实效。     

Codon sextets with leading role of serine create “ideal” symmetry classification scheme of the genetic code

The standard classification scheme of the genetic code is organized for alphabetic ordering of nucleotides. Here we introduce the new, “ideal” classification scheme in compact form, for the first time generated by codon sextets encoding Ser, Arg and Leu amino acids. The new scheme creates the known purine/pyrimidine, codon–anticodon, and amino/keto type symmetries and a novel A + U rich/C + G rich symmetry. This scheme is built from “leading” and “nonleading” groups of 32 codons each. In the ensuing 4 × 16 scheme, based on trinucleotide quadruplets, Ser has a central role as initial generator. Six codons encoding Ser and six encoding Arg extend continuously along a linear array in the “leading” group, and together with four of six Leu codons uniquely define construction of the “leading” group. The remaining two Leu codons enable construction of the “nonleading” group. The “ideal” genetic code suggests the evolution of genetic code with serine as an initiator.     

物理学知识原理向遗传学教学渗透的实践与思考

遗传学是生物学科的核心课程,在生物学的教学与研究中具有十分重要的作用,而遗传学的知识原理与物理学的知识原理具有一定的相似性。由于遗传学教学内容较为抽象,加之学生在中学阶段所学的遗传学基础知识相对薄弱,导致部分学生缺乏学习兴趣。如何采用“渗透式”的教学方法将学生深厚的物理学知识原理引入遗传学课堂是一个值得探讨的问题。近年来,笔者应用物理学的知识原理,将部分物理知识与遗传知识进行类比教学和渗透式教学,提升学生对遗传学知识的认识层次和理解水平,进而提高学生的学习能力和创新思维能力。     

基因工程培育可恢复的植物雄性不育系的研究进展

植物雄性不育是植物杂种优势利用的资源, 具有重要的生产利用价值。植物雄性不育可从自然突变、人工诱变和远缘杂交中发现, 现在可通过细胞工程和基因工程等方法来创造。文章综述了利用基因工程方法制备雄性不育品系及其相应的育性恢复策略, 分为“单组分策略”和“双组分策略”。其中利用“单组分策略”制备的不育植株是条件型雄性不育(可逆转的雄性不育), 它能在特定的条件下实现雄性可育与不育的转换, 实践中可直接作为两用系(不育系和保持系)用于两系法杂交制种; “双组分策略”是利用基因互作和亲本杂交直接培育雄性不育系, 或利用基因互作原理分别研制不育系和恢复系, 用于三系法生产杂交种。文章分析了 “单组分策略”和“双组分策略”的基因工程方法培育雄性不育系及其相应育性恢复策略优缺点, 对以上两种技术路线在实际应用中的现状作了分析和展望。     

Single pot sequential crystallization-distillation as a new purification procedure

A new purification procedure exploiting the simultaneous presence of a solid, liquid, and gas phase in a low surface area system is proposed and discussed. The assumptions of vanishingly low diffusion coefficients in the solid phase and that of the presence of a single “effective impurity” allow to plan the sequence of operations starting from the knowledge of just the melting and boiling points of the substance to be purified and of those of the “effective impurity”. Examples and results are presented.     

The emergence of ribozymes synthesizing membrane components in RNA-based protocells

A significant problem of the origin of life is the emergence of cellular self-replication. In the context of the “RNA world”, a crucial concern is how the RNA-based protocells could achieve the ability to produce their own membrane. Here we show, with the aid of a computer simulation, that for these protocells, there would be “immediately” a selection pressure for the emergence of a ribozyme synthesizing membrane components. The ribozyme would promote the enlargement of cellular space and favor the incoming (by permeation) of RNA's precursors, thus benefit the replication of inner RNA, including itself. Via growth and division, protocells containing the ribozyme would achieve superiority and spread in the system, and meanwhile the ribozyme would spread in the system. The present work is inspiring because it suggests that the transition from molecular self-replication to cellular self-replication might have occurred naturally (and necessarily) in the origin of life, leading to the emergence of Darwinian evolution at the cellular level.     

A Report of Two cases of Al-Awadi Raas-Rothschild Syndrome (AARRS) supporting that “Apparent” Phocomelia differentiates AARRS from Schinzel Phocomelia Syndrome (SPS)

Although there is a long list of syndromes with phocomelia, there are only two syndromes in which there is concurrent pelvic dysplasia and phocomelia: Al-Awadi–Raas-Rothschild syndrome (AARRS) and Schinzel phocomelia syndrome (SPS). Currently, there is a diagnostic confusion between the two syndromes and both have the same MIM entry (MIM 276820). We believe that the two syndromes are different entities and we also believe that the limb defect in SPS is a “true” phocomelia while the limb defect in AARRS is an “apparent” phocomelia. “Apparent” phocomelia describes the most severe form of ulnar ray deficiency in which there is absent ulna with radio-humeral synostosis. “Apparent” phocomelia is diagnosed radiologically by three radiological features: the apparently single bone occupying the arm/forearm appears relatively long, the area of radio-humeral synostosis will have thicker cortex with or without slight angulation, and the lower end of the bone resembles the lower end of a radius and not a humerus. In this paper, we present two new cases of AARRS from two different Saudi Arabian tribes: one case with R292C mutation of WNT7A with bilateral “apparent” phocomelia and a second case with a novel c.814G>T mutation of the WNT7A gene (resulting in wnt7a protein truncation at position 272) with unilateral “apparent” phocomelia. We reviewed previously reported cases of AARRS and SPS to further delineate the differences between these two syndromes. We make the argument that these two syndromes are two different entities and hence require two different MIM entries.     

Regeneration of whole plants from callus culture of diverse genetic lines of Pisum sativum L.

Sixteen genetic lines of peas were screened for their ability to regenerate whole plants from callus cultures. Epicotyl sections from germinating seeds were placed on callus-inducing medium; the resulting callus was subcultured monthly and was tested every other month for its regeneration ability. Six lines were found that would regenerate after 2 months' growth as callus. Four of these continued to regenerate after 4 months and, of these, two after 6 months. The cultivars Frosty and Alaska were among the lines that would not regenerate at all.Michigan Agricultural Experiment Station Journal Article No. 8932     

Dynamics of the glutamic acid 242 side chain in cytochrome c oxidase

In many cytochrome c oxidases glutamic acid 242 is required for proton transfer to the binuclear heme a₃/Cu_B site, and for proton pumping. When present, the side chain of Glu-242 is orientated “down” towards the proton-transferring D-pathway in all available crystal structures. A nonpolar cavity “above” Glu-242 is empty in these structures. Yet, proton transfer from Glu-242 to the binuclear site, and for proton-pumping, is well established, and the cavity has been proposed to at least transiently contain water molecules that would mediate proton transfer. Such proton transfer has been proposed to require isomerisation of the Glu-242 side chain into an “up” position pointing towards the cavity. Here, we have explored the molecular dynamics of the protonated Glu-242 side chain. We find that the “up” position is preferred energetically when the cavity contains four water molecules, but the “down” position is favoured with less water. We conclude that the cavity might be deficient in water in the crystal structures, possibly reflecting the “resting” state of the enzyme, and that the “up/down” equilibrium of Glu-242 may be coupled to the presence of active-site water molecules produced by O₂ reduction.     

Découverte d’un site d’art rupestre en Cyrénaïque (Libye) : Kaf Tahr

In April 2009, a new rock art site was discovered in Libya. Kaf Tahr is situated in Cyrenaica, in the Djebel Akhdar (the “green mountain”). This new site with engravings displays several interests. Firstly, it is only the third rock art site discovered - or at least published - in Cyrenaica. Secondly, this rock shelter is the only one that had shown engravings belonging to at least two different chronological periods, the first one being very probably prehistoric, and the second, post-prehistoric. Finally, the engraving of a man (with a sword and a shield) and the engraving of a horse are the first discovered in the area. These two engravings could have been realized in the protohistoric period. This period is well-known in the Libyan Fezzan (“libyco-berberian period” or “horse period”) but it has never been defined in Cyrenaica. Owing to the lack of research, the long period separating the end of Prehistory from the beginning of the greek colonization is hitherto totally unknown. If these engravings would belong to this period, they would be the first elements attesting of a metal work and a horse domestication in Cyrenaica before the historic period.     

A “Krokodil” emerges from the murky waters of addiction. Abuse trends of an old drug

“Krokodil” is the street name for the semi-synthetic opioid derivative desomorphine. Although an old drug, it re-staged on “drug arena” during the last decade causing detrimental effects to its users. Despite the fact that Russia and other former Soviet Republics were the initial plagued countries, “krokodil” arrived in Europe and United States lately, as a substitute of the relative expensive, and in many cases unavailable, heroin. It can be easily manufactured in home-environment from codeine and causes significant health problems, even deaths worldwide. The aim of this review is to summarize the current knowledge about this drug, concerning its chemistry, synthesis, pharmacology and toxicology. Published or reported “krokodil” related cases, fatalities or intoxications, as well as self reports from drug users are reviewed. The existing analytical methodologies for the determination of desomorphine in biological samples as well as its legal status are also presented.