不同基因型小麦（Triticum aestivum）京411与小偃54抗光氧化特性及其机理的比较研究

对两种不同基因型小麦京411（北京地区高产小麦品种）和小偃54（在生产上已应用二十年的优良品种）幼苗及旗叶光抑制特性进行了比较研究，着重探讨了它们抗光氧化的差异及其机理，主要结果如下： 1. 强光条件下，同京411相比小偃54能保持较高的光合色素含量和放氧速率。其DCPIP光还原活性也较高。 2. 光谱特性分析表明，强光胁迫下小偃54在红区及蓝区的特征性吸收峰及F683荧光发射峰下降的幅度明显小于京411相应峰位的下降。 3. 色素蛋白复合物分析表明，强光条件下，京411色素蛋白复合物中LHCII聚合体大量的解聚，而小偃54在强光条件下仍能保持较高比例的LHCII聚合体。这可能在一定的程度上有利于小偃54在强光下维持较强的激发能耗散的能力。 4. 多肽SDS-PAGE分析表明，强光对不同基因型小麦中同PSII光抑制敏感性有关的两个外周蛋白23kD和17kD的影响不同。光抑制明显地降低了京411的23kD和17kD的含量，而对于小偃54中这两个外周蛋白23kD和17kD的影响不大。强光条件下小偃54旗叶PSII颗粒中捕光色素蛋白27kD含量提高，而京411捕光色素蛋白27kD含量明显的下降。 5. 上述结果表明，西北地区的优良小麦品种小偃54同北京地区的高产品种京411相比更耐强光的胁迫，其抗光氧化的能力较强。 6. 进一步分析表明，同京411相比，小偃54抗光氧化的主要原因是其不仅含有较大的叶黄素循环的色素库，而且在强光下能维持高的VDE酶活性及高水平的叶黄素循环的脱环化水平。 7. 叶黄素循环色素在两个小麦品种类囊体膜色素蛋白复合体中的分布存在差异，抗光氧化的小偃54大部分的VAZ分布在PSII上，其中绝大部分集中在LHCII聚合体上。LHCII上VAZ的集中分布可能有利于在强光下对过多光能的耗散，减少过多激发能对PSII的损伤。 8. 类囊体膜流动性分析表明，叶黄素循环参与了对类囊体膜流动性的调整，对维持强光下抗光氧化品种小偃54的类囊体膜相对稳定起重要作用。 9. 依赖于叶黄素循环的热耗散是抗光氧化品种小偃54的一个主要的光保护途径。

水稻菠菜紫黄质脱环氧化酶基因的克隆遗传转化及其特性的研究

自发现叶黄素循环具有热耗散的作用后它被引起广泛的关注目前普遍认为叶黄素循环的色素定位于天线色素蛋白复合体上在跨膜质子梯度pH形成后玉米黄质Z和环氧玉米黄质A能够从叶绿素中吸收过多的激发能并以热能的形式耗散到体外从而保护光合器官免受强光的破坏紫黄质脱环氧化酶VDE是叶黄素循环的关键酶在较低的pH条件下它能在数分钟内将紫黄质V转变为Z和A本论文从水稻和菠菜中克隆了编码VDE酶的基因并通过转基因植物进一步研究了叶黄素循环在热耗散方面的作用主要获得了以下结果 首次从两个水稻亚种籼稻和粳稻中克隆了Rvde基因分别命名为iRvde和jRvde的全长cDNA序列分别长1647bp和1887bp两者开放阅读框的同源性为98%与其它已知vde基因的同源性在60以上推导两者均编码446个氨基酸其中转运肽序列长98个氨基酸两者成熟蛋白的氨基酸序列完全相同与已知VDE成熟蛋白的同源性在75%以上其中与小麦的同源性最高达87.4 通过PCR扩增获得了Rvde基因的核基因组DNA序列在它们的编码区中含有4个内含子其长度在jRvde中分别为105bp327bp81bp和69bp而iRvde基因的第2个内含子长425bp与jRvde的第2个内含子差别较大内含子的AT含量为6063%其两端为典型的GT/AG结构 构建了Rvde基因的原核表达载体pET-Rvde在0.4mmol/L IPTG的诱导下该基因能在大肠杆菌BL21(DE3)中大量表达SDS-PAGE和Western杂交表明表达蛋白的分子量约为 43 kDa随着IPTG诱导时间的延长蛋白量逐渐增加诱导4h后它占大肠杆菌总蛋白的25左右吸收光谱差值A502-540随反应的进行逐渐增大反应体系总色素的HPLC分析表明V逐渐降低而Z刚好相反说明表达的蛋白具有与活体VDE酶相同的功能能在体外将V转变为A和Z 从菠菜中克隆了Svde基因并构建了该基因的反义抑制植物表达载体pCB-antiSvde用根癌农杆菌介导法转化烟草获得了大量的转基因植株再生的愈伤组织经GUS染色后呈蓝色PCR扩增潮霉素抗性基因hpt和Svde基因结果显示在转基因植株T0和T1代中都分别扩增出1.0 kb和1.4 kb的目的片段而在未转化的对照植株中没有扩增转基因植株的T0代种子在潮霉素培养基上的萌发数与未萌发数的比值为3:1符合单基因的孟德尔分离规律从T1代转基因植株中筛选出抑制程度较强的一个株系A29Southern杂交结果表明外源Svde基因已整合到烟草的基因组中并且只有一个插入位点通过冻融法从该植株的类囊体中提取VDE酶其酶活性为3.2是对照植株的45.7表明VDE酶受到了抑制荧光动力学及HPLC测定结果显示强光处理后在转基因植株中Z和A的形成较少非光化学淬灭NPQ值较对照低Fv/Fm的下降较对照快表明转基因植株的热耗散能力下降进而说明叶黄素循环具有热耗散的功能 同时还建立了根癌农杆菌介导的水稻遗传转化体系并初步作了转化Svde基因的试验另外还建立了一种适合于筛选转基因植株的DNA微量提取法此方法操作快捷方便一个人在一天内能制备50多个样品100mg的植物鲜样平均可获得40µg的DNA提取的DNA可直接用于PCR反应酶切分析及Southern分析

Geometries and electronic properties of AunPdm (n=1-4, m =-1, 0, 1) clusters

Possible conformers for AunPdm (n = 1-4, m = -1, 0, 1) clusters have been presented and studied by use of density functional theory. The results indicate that for n = 2, linear conformer with C-infinityv symmetry is the most stable for anion species, while for cation and neutral species, conformer with C-2v symmetry is the most stable. For n = 3, 4, conformers with C-2v symmetry (kite-shape) are energetically favored. The calculated electron affinities (EAs) and vertical detachment energies (VDEs) are in good agreement with experiments for n = 1-4. It is also interesting to note that for even n (n = 2, 4), the most stable conformers do not give the best agreement between calculated and experimental EA and VDE values, while for odd n (n = 3), the lowest energy conformer also gives the best agreement. The ionization potentials (IPs) of AunPd clusters are calculated as well.

A genetic algorithm based economic dispatch (GAED) with environmental constraint optimisation

The role of renewable energy in power systems is becoming more significant due to the increasing cost of fossil fuels and climate change concerns. However, the inclusion of Renewable Energy Generators (REG), such as wind power, has created additional problems for power system operators due to the variability and lower predictability of output of most REGs, with the Economic Dispatch (ED) problem being particularly difficult to resolve. In previous papers we had reported on the inclusion of wind power in the ED calculations. The simulation had been performed using a system model with wind power as an intermittent source, and the results of the simulation have been compared to that of the Direct Search Method (DSM) for similar cases. In this paper we report on our continuing investigations into using Genetic Algorithms (GA) for ED for an independent power system with a significant amount of wind energy in its generator portfolio. The results demonstrate, in line with previous reports in the literature, the effectiveness of GA when measured against a benchmark technique such as DSM.

Hybrid energy storage for energy harvesting powered wireless sensor networks

Science Foundation Ireland (CSET - Centre for Science, Engineering and Technology, grant 07/CE/I1147); Scientific Foundation Ireland (ITOBO (398-CRP))

Predictive reliability, prognostics and risk assessment for power modules

This paper describes a framework that is being developed for the prediction and analysis of electronics power module reliability both for qualification testing and in-service lifetime prediction. Physics of failure (PoF) reliability methodology using multi-physics high-fidelity and reduced order computer modelling, as well as numerical optimization techniques, are integrated in a dedicated computer modelling environment to meet the needs of the power module designers and manufacturers as well as end-users for both design and maintenance purposes. An example of lifetime prediction for a power module solder interconnect structure is described. Another example is the lifetime prediction of a power module for a railway traction control application. Also in the paper a combined physics of failure and data trending prognostic methodology for the health monitoring of power modules is discussed.

Combining metagenomics with metaproteomics and stable isotope probing reveals metabolic pathways used by a naturally occurring marine methylotroph

A variety of culture-independent techniques have been developed that can be used in conjunction with culture-dependent physiological and metabolic studies of key microbial organisms, in order to better understand how the activity of natural populations influences and regulates all major biogeochemical cycles. In this study, we combined DNA-stable isotope probing with metagenomics and metaproteomics to characterize an as yet uncultivated marine methylotroph that actively incorporated carbon from 13C-labeled methanol into biomass. By metagenomic sequencing of the heavy DNA, we retrieved virtually the whole genome of this bacterium and determined its metabolic potential. Through protein-stable isotope probing, the RuMP cycle was established as the main carbon assimilation pathway, and the classical methanol dehydrogenase-encoding gene mxaF, as well as three out of four identified xoxF homologues were found to be expressed. This proof-of-concept study is the first in which theculture-independent techniques of DNA- and protein-stable isotope probing have been used to characterize the metabolism of a naturally-ocurring Methylophaga-like bacterium in the marine environment (i.e. M. thiooxydans L4) and thus provides a powerful approach to access the genome and proteome of uncultivated microbes involved in key processes in the environment

The Koundoum sheep breed in Niger: morpho-biometric study and description of the production system

The diffusion of highly productive breeds across developing countries goes along with a neglect of indigenous breeds, which are well suited to their environment but often show low yields. Thus, in Niger, the flock of Koundoum sheep are rapidly decreasing. The Koundoum is one of the few wool sheep breeds of Africa and shows important adaptive feature to its native environment, i.e. the humid pastures on the banks of the Niger River. To characterise the breed and to understand its production context, a survey has been conducted in 104 herds in four communes along the Niger River (Kollo, Tillabery, Say and Tera). Nine body measurements, including live weight, were taken on 180 adult sheep (101 females and 79 males). The herds varied from 2 to 60 heads, with a median size of eight animals and two thirds of the herds having less than 10 animals. Mainly fed on natural pastures, 85.6% of the herds received crop residues. Only natural mating was practiced. Veterinary care was restricted to anti-helminthic and some indigenous treatments. The frequent affiliation of breeders to professional unions appeared as favourable to the implementation of a collective conservation program. The Koundoum sheep were white or black coated, with the black colour being most frequent (75.6%). Wattles were present in both sexes at similar frequencies of around 14%. All biometric variables were significantly and positively correlated between them. The thoracic perimeter showed the best correlation with live weight in both males and females. Three variables were selected for live weight prediction: thoracic perimeter, height at withers and rump length. From the present study, it is expected that the in situ conservation of the Koundoum sheep will be highly problematic, due to lack of market opportunities for wool and the willingness of smallholders to get involved in pure Koundoum rearing.

Prevalencia de enfermedad celiaca en Latinoamérica: revisión sistemática de la literatura y meta-análisis

Introducción: La enfermedad celiaca (EC) es una enfermedad autoinmune (EA) intestinal desencadenada por la ingesta de gluten. Por la falta de información de la presencia de EC en Latinoamérica (LA), nosotros investigamos la prevalencia de la enfermedad en esta región utilizando una revisión sistemática de la literatura y un meta-análisis. Métodos y resultados: Este trabajo fue realizado en dos fases: La primera, fue un estudio de corte transversal de 300 individuos Colombianos. La segunda, fue una revisión sistemática y una meta-regresión siguiendo las guías PRSIMA. Nuestros resultados ponen de manifiesto una falta de anti-transglutaminasa tisular (tTG) e IgA anti-endomisio (EMA) en la población Colombiana. En la revisión sistemática, 72 artículos cumplían con los criterios de selección, la prevalencia estimada de EC en LA fue de 0,46% a 0,64%, mientras que la prevalencia en familiares de primer grado fue de 5,5 a 5,6%, y en los pacientes con diabetes mellitus tipo 1 fue de 4,6% a 8,7% Conclusión: Nuestro estudio muestra que la prevalencia de EC en pacientes sanos de LA es similar a la notificada en la población europea.

Percentile growth charts for biomedical studies using a porcine model

Increasing rates of obesity and heart disease are compromising quality of life for a growing number of people. There is much research linking adult disease with the growth and development both in utero and during the first year of life. The pig is an ideal model for studying the origins of developmental programming. The objective of this paper was to construct percentile growth curves for the pig for use in biomedical studies. The body weight (BIN) of pigs was recorded from birth to 150 days of age and their crown-to-rump length was measured over the neonatal period to enable the ponderal index (Pl; kg/m(3)) to be calculated. Data were normalised and percentile curves were constructed using Cole's lambda-mu-sigma (LMS) method for BW and PI. The construction of these percentile charts for use in biomedical research will allow a more detailed and precise tracking of growth and development of individual pigs under experimental conditions.

In silico identification and three-dimensional modelling of the missense mutation in ADAMTS2 in a sheep flock with dermatosparaxis

Background Dermatosparaxis (Ehlers–Danlos syndrome in humans) is characterized by extreme fragility of the skin. It is due to the lack of mature collagen caused by a failure in the enzymatic processing of procollagen I. We investigated the condition in a commercial sheep flock. Hypothesis/Objectives Mutations in the ADAM metallopeptidase with thrombospondin type 1 motif, 2 (ADAMTS2) locus, are involved in the development of dermatosparaxis in humans, cattle and the dorper sheep breed; consequently, this locus was investigated in the flock. Animals A single affected lamb, its dam, the dam of a second affected lamb and the rams in the flock were studied. Methods DNA was purified from blood, PCR primers were used to detect parts of the ADAMS2 gene and nucleotide sequencing was performed using Sanger's procedure. Skin samples were examined using standard histology procedures. Results A missense mutation was identified in the catalytic domain of ADAMTS2. The mutation is predicted to cause the substitution in the mature ADAMTS2 of a valine molecule by a methionine molecule (V15M) affecting the catalytic domain of the enzyme. Both the ‘sorting intolerant from tolerant’ (SIFT) and the PolyPhen-2 methodologies predicted a damaging effect for the mutation. Three-dimensional modelling suggested that this mutation may alter the stability of the protein folding or distort the structure, causing the protein to malfunction. Conclusions and clinical importance Detection of the mutation responsible for the pathology allowed us to remove the heterozygote ram, thus preventing additional cases in the flock.

Characteristics of the equine embryo and fetus from days 15 to 107 of pregnancy

In spite of numerous, substantial advances in equine reproduction, many stages of embryonic and fetal morphological development are poorly understood, with no apparent single source of comprehensive information. Hence, the objective of the present study was to provide a complete macroscopic and microscopic description of the equine embryo/fetus at various gestational ages. Thirty-four embryos/fetuses were aged based on their crown rump length (CRL), and submitted to macroscopic description, biometry, light and scanning microscopy, as well as the alizarin technique. All observed developmental changes were chronologically ordered and described. As examples of the main observed features, an accentuated cervical curvature was observed upon macroscopic examination in all specimens. In the nervous system, the encephalic fourth ventricle and the encephalic vesicles forebrain, midbrain, and hindbrain, were visualized from Day 19 (ovulation = Day 0). The thoracic and pelvic limbs were also visualized; their extremities gave rise to the hoof during development from Day 27. Development of other structures such as pigmented optical vesicle, liver, tail, cardiac area, lungs, and dermal vascularization started on Days 25, 25, 19, 19, 34, and 35, respectively. Light and scanning microscopy facilitated detailed examinations of several organs, e.g., heart, kidneys, lungs, and intestine, whereas the alizarin technique enabled visualization of ossification. Observations in this study contributed to the knowledge regarding equine embryogenesis, and included much detailed data from many specimens collected over a long developmental interval. (C) 2011 Elsevier Inc. All rights reserved.

Assessment of DGAT1 and LEP gene polymorphisms in three Nelore (Bos indicus) lines selected for growth and their relationship with growth and carcass traits

The aim of this study was to analyze LEP and DGAT1 gene polymorphisms in 3 Nelore lines selected for growth and to evaluate their effects on growth and carcass traits. Traits analyzed were birth, weaning, and yearling weight, rump height, LM area, backfat thickness, and rump fat thickness obtained by ultrasound. Two SNP in the LEP gene [LEP 1620(A/G) and LEP 305(T/C)] and the K232A mutation in the DGAT1 gene were analyzed. The sample consisted of 357 Nelore heifers from 2 lines selected for yearling weight and a control line, established in 1980, at the Estacao Experimental de Zootecnia de Sertaozinho (Sertaozinho, Brazil). Three genotypes were obtained for each marker. Differences in allele frequencies among the 3 lines were only observed for the DGAT1 K232A polymorphism, with the frequency of the A allele being greater in the control line than in the selected lines. The DGAT1 K232A mutation was associated only with rump height, whereas LEP 1620(A/G) was associated with weaning weight and LEP 305(T/C) with birth weight and backfat thickness. However, more studies, with larger data sets, are necessary before these makers can be used for marker-assisted selection.

Provning av ackumulatorsystem för solvärmeanläggningar

Inom projektet provades 10 konfigurationer av samma ackumulatortank. Tankarna utsattes under kontrollerade förhållanden för en 6-dagars testcykel. Under testet tillfördes varje tank värme från en (simulerad) solfångare och, i den mån det behövdes, tillsatsvärme från elpatronen. Väderförhållanden under de sex dagarna var två fina, en växlande, två dåliga och ytterligare en växlande dag i nämnd följd. De flesta systemkonfigurationer klarade sig under de soliga dagarna utan energitillskott från elpatronen och förmådde dessutom att lagra värnlen så att även tappningar på följande dag med "växlande" väder kunde ske utan el-tillskott. De molniga dagarna behövde alla systemkonfigurationer el-tillskott. Solvärmesystemens täckningsgrad varierade mellan 36,5 % för det sämsta systemet till 70, 3 % för det bästa. En ackumulatortank med två seriekopplade tappvarmvattenvärmeväxIare (en i botten för förvärmning och en i tankens övre del för slutvärmning) ger betydligt bättre resultat än en tank med bara en enda sådan värmeväxlare. Tankens volym var i de utförda provningarna 750 liter, solfångarstorleken 10 m2 och lasten 13 kWh per dag. För dessa förutsättningar ger en yttre solvärmeväxlare inga mätbara fördelar gentemot en tillräcklig stor inbyggd värmeväxlare. De gjorda försöken visar, att alla tankkonfigurationerna visar dålig skiktning. Ett fortsatt arbete bör göras för att minska omblandningen i tanken vid både inladdning och uttag av värme.

Relação entre medidas ultrassônicas e da carcaça de bubalinos Murrah abatidos em diferentes períodos de confinamento

Os objetivos neste trabalho foram estimar as correlações entre medidas obtidas por ultrassonografia e na carcaça e acompanhar o desenvolvimento da área de olho-de-lombo e a deposição de gordura de búfalos em diferentes períodos de confinamento. Foram utilizados 20 bubalinos da raça Murrah, castrados, abatidos aos 75, 100, 125 ou 150 dias de confinamento. As medidas realizadas foram área de olho-de-lombo, espessura de gordura subcutânea do dorso e espessura de gordura da garupa, mensuradas por ultrassonografia quando os búfalos atingiram o tempo de abate e na carcaça, após o abate. A espessura de gordura subcutânea da carcaça foi avaliada utilizando-se paquímetro e a área de olho-de-lombo da carcaça, régua do quadrante de pontos. O período de confinamento apresentou efeito linear crescente na área de olho-de-lombo e nas espessuras de gordura do dorso e da garupa avaliadas por ultrassom e na carcaça. O efeito linear positivo entre 75 e 150 dias de confinamento, tanto para a área de olho-de-lombo como para espessura de gordura medidas no dorso e na garupa, comprovou que os animais ainda não haviam atingido a maturidade. As correlações entre as medidas obtidas por ultrassom e na carcaça foram 0,82 para área de olho-de-lombo e 0,85 para espessura de gordura subcutânea no dorso. As características de carcaça medidas por ultrassom em bubalinos apresentam boas correlações com as medidas realizadas na carcaça no momento do abate, o que permite, em bubalinos da raça Murrah castrados e oriundos de rebanho leiteiro, acompanhar as alterações dessas características durante o desenvolvimento.