PANEL PERFORMANCE AND NUMBER OF EVALUATIONS IN A DESCRIPTIVE SENSORY STUDY

The assessor performance is a key point in a sensory evaluation. In particular, at the end of a session, a decrease of the performance can be feared. We propose to analyze this performance with various criteria: usual ones as the main product effect or the error variance; a new one measuring the perceived products variability. The performance can then be studied all along the session from two points of view: in taking into account the only products tested at a given instant (named instantaneous); in taking into account all the products tested up to a given instant (named cumulative). In the presented example, in spite of the large number of products successively tested by each assessor, the instantaneous performance of the panel shows no significant deterioration. Furthermore, when the number of products tested by each assessor increases, more significant product effects can be obtained thanks to the accumulation of the amount of data. This shows that the number of products that can be reasonably studied by one assessor during one session is generally underestimated.     

MODELING THE EVOLUTION OF THE PERFORMANCE OF A SENSORY PANEL: A MIXED-MODEL AND CONTROL CHART APPROACH

A sensory panel is often used to profile the same type of product with the same set of attributes for many years. We are interested in characterizing the evolution of the performance of such a panel (and its panelists) over time. This article presents a methodology based on a mixed‐model approach that takes into account the evolution of both panel and panelist in the same model. At the panel level, linear and quadratic evolutions of the performance are tested. At the panelist level, the method allows detection of whether some panelists perform better than others, and whether this difference remains the same or evolves over time. This mixed‐model approach is followed by a graphical representation using a control chart method to identify occasional outliers. Data used to illustrate this methodology are eight sensory profiling data sets collected on ready‐made frozen meals between 1997 and 2001 (every 6 months). The performance index chosen as an example in this study is the individual repeatability measured by standard deviation over replicates.     

窦房结优势起搏点兴奋向心房传导方式的探讨

本文采用同步双标测法,研究了窦房结(SN)优势起搏点兴奋向心房传导的规律。在14只麻醉狗心脏界沟部缝上一装有32个电极的电极板,标测优势起搏点(P点),最早起始负电位点(N点),心房激动过程图及最早激动点(O点)。在用异丙肾上腺索、心得安或刺激迷走神经使P点移位后,我们研究了P点位置与P—O、P—N的关系。在计60次实验中:(1)P—O、P—N多数并不重叠(分别为46次和40次);(2)随着P点从SN头部向尾部移位,O(N)点在P点头侧的出现率下降,在P点尾侧的出现率上升;(3)出现两个O点者23次,出现两个N点者11次,但P点始终只有一个。 本文提出了SN兴奋在SN内优先向头、尾两端扩布,再传向心房肌的窦房传导模式。并对心房激动多中心起源、界沟部兴奋超速传导等现象及Boiaeau的“心房综合起搏”假说进行了讨论。     

灌浆期气象因子对杂交中籼稻米碾米品质和外观品质的影响

 以`II优7号'和`4228A/江恢15'两个杂交中稻组合为材料,通过分期播种处理,研究了灌浆期气象因子与杂交中稻稻米碾米品质和外观品质的关系。结果表明：在稻谷碾米品质和外观品质的5项指标中,显著受灌浆期气象因子影响的有整精米率、垩白粒率和垩白度3项指标,显著影响这3项指标的是齐穗后0～20 d 6个气象因子中的相对湿度、日均气温、日最低气温3个,齐穗后21～30 d的气象因子对米质的影响不显著。从总体上看, 齐穗后0～20 d的日均气温和日最低气温低, 相对湿度大,有利于提高整精米率,降低垩白粒率和垩白     

广西栽培与野生岩黄连的质量比较研究

通过对广西栽培与野生岩黄连(Corydalis saxicola Bunting)全草的性状、组织构造、化学反应、薄层层析、紫外吸收的比较,表明栽培岩黄连与当地野生品质量基本一致,为广西发展岩黄连资源提供科学依据。     

THE EFFECT OF SEASON ON A BIOTIC WATER QUALITY INDEX: A CASE STUDY OF THE YELLOW JACKET AND MAZOWE RIVERS,ZIMBABWE.

Summary

The effect of season on the South African Scoring System (SASS) biotic index for rapid assessment of water quality using benthic macroinvertebrates was investigated using the Yellow Jacket and Mazowe Rivers in Zimbabwe as a case study. Several impacts in the area degraded water quality. These were habitat destruction, acid mine drainage and organic pollution. SASS score at all sites changed with season. At and downstream from polluted sites, water quality determined using SASS was best at the end of the rainy season and it deteriorated steadily into the dry season. SASS scores from sites upstream of pollution appeared to improve towards the end of the rainy season. Average Score Per Taxon indices did not have a significant pattern of seasonal variation. SASS was designed to monitor water quality in South African rivers, so when implementing any monitoring programme, selection of sampling season and the interpretation of results in areas with similar climate patterns should take seasonal effects into account, It must be appreciated that water quality at impacted sites is a dynamic variable related both to the activities of polluters and to season.     

产过敏素harpin的固氮工程菌的某些特性研究

研究了产过敏素harpin的固氮工程菌（Enterobacter cloacaeE4)在番茄,烟草叶片上的致过敏能力及该菌所携的双质粒的稳定性。试验结果表明：E4与DH5（pCPP430)致过敏能力的速度和强度基本相同,E4与308R（pCPP430)相比,烟草上它们致过敏能力的速度基本一致。但308R（pCPP430)致过敏能力的强度更强,在番茄叶片上,E4和308R（pCPP430)致过敏能力的速度和强度基本一样,E4所携的双质粒pCPP430和pMC73A在宿主细菌中是不稳定的,在宿主细菌连续繁殖过程中,质粒pCPP430和pMC73A随宿主细菌的繁殖而发生缺失,当连续传代48代时,双质粒的丢失率达100%,而且各含一种质粒的细胞产生的机率基本相同。     

南水北调中线水源区浮游植物与水质评价

通过2003年3月至2005年8月对南水北调中线水源区水体浮游植物的调查,结果表明:该水域共有浮游植物8门63属96种及变种,其中以硅藻的种类最多,其次是绿藻和蓝藻。藻类的细胞密度表现出明显的季节变化,夏季最高冬季最低。从近3年的浮游生物检测结果可知,整个水源区年平均藻类细胞密度为109.33×10⁴ cells·L^-1,处于较低的水平,而且未检出水体重污染指示种,充分说明南水北调中线水源区富营养化程度较低。运用Margalef和Menkinick多样性指数对该水域的水质进行评价,数据显示2003~2005年该水源区的d值和α值,各采样点之间的差异并不显著,说明各采样点的水质营养状况虽有差异,但总体水平基本相当。水质评价结果:水体为寡污型,基本处于中营养状态。通过水生生物资源的调查,做好水源区的长期生态监测,可为建立中线水源区长期生态研究数据信息库及库区生态环境保护政策制定提供理论依据,对保证中线水质质量十分重要。     

QUANTITATIVE STUDY OF NUCLEIC ACIDS AND PROTEINS IN THE SHOOT APEX OF SINAPIS ALBA DURING TRANSITION FROM THE VEGETATIVE TO THE REPRODUCTIVE CONDITION

Quantitative changes in DNA, histone, RNA, and total protein have been measured in meristematic cells during floral evocation.² A single 22-hr, long-day exposure induced two-month-old vegetative plants of Sinapis alba to flower. Periodic collections of shoot apices were made and stained with Schiff's reagent (DNA), azur B (RNA), alkaline fast green (histone), and naphthol yellow S (total protein). The two-wavelength method was used for DNA and histone measurements and the one-wavelength, two-area procedure was chosen for RNA and total protein determinations. The DNA and histone amounts per cell decreased to a minimum value 34 hr after treatment, and most of the nuclei shifted from 4C to 2C values. DNA and histone quantities paralleled each other from 34–46 hr, after which time the histone values continued to increase and the DNA values decreased. The RNA values increased rapidly after treatment as did the total protein quantities, after a slight decrease at 34 hr concurrent with the 4C to 2C cell population shift. The significance of these events is discussed in relation to the changes which were previously described in the shoot apex of Sinapis in transition to flowering.     

从甘蓝夜蛾分离的一种微孢子虫生物学特性研究

从广州市郊菜地捕捉的甘蓝夜蛾(\%Barathra brassicae L.\%)幼虫体中分离到一种微孢子虫(简称BabM)。孢子呈长卵圆形,大小为：402±036μm×199±036μm;孢子表面抗原与家蚕传统微粒子孢子(\%Nosema bombycis,简称N.b.\%)具共同抗原性;BabM微孢子虫孢子的内部结构、发育的特征与\%N.b.\%孢子相类似。BabM微孢子虫对三龄起蚕感染中量(IC５０)为６０3×１０４粒孢子;经卵传染频率较高。初步阐明了从甘蓝夜蛾分离的这种微孢子虫与家蚕\%N.b.\%同为\%Nosema bombycis\%种,但存在着变异现象。     

烟草愈伤组织继代培养与分化期间核酸代谢的比较研究

柳叶烟草愈伤组织在分化和芽原基形成期间,DNA 和RNA 含量均高于继代培养物;在芽原基形成后和幼芽生长期间(12天以后),DNA和RNA 含量持续上升,而同期继代培养物巳进入生长静止期,DNA 和RNA 含量基本不变或略有下降。根据RNA 电泳结果还进一步分析了两种愈伤组织培养物各RNA 组分变化与总RNA 含量变化的关系。分化培养物在芽原基形成时有明显升高的RNase 活性峰和持续上升的RNA 合成速率;而此时期继代培养物的RNase 活性及RNA 合成能力均较低;分化愈伤组织的DNA 合成速率在幼芽生长期间仍维持上升趋势,且显著高于同期继代愈伤组织的合成速率。这些结果表明,烟草愈伤组织分化培养物比继代培养物有更旺盛的核酸代谢能力。     

褐菖■精细胞晚期的变化及精子结构研究

本文研究卵胎生硬骨鱼褐菖（Ｓｅｂａｓｔｉｓｃｕｓｍａｒｍｏｒａｔｕｓ）精细胞的成熟变化和精子结构。褐菖精细胞发育晚期已具有硬骨鱼类精子的结构雏形：细胞核的背面较平坦,腹面稍外鼓,呈弧面;染色质浓缩成团块状,核的腹侧和后端的染色质较致密;中心粒复合体由近端中心粒和基体组成,近端中心粒和基体排成“Ｌ”形;近端中心粒向细胞核的背侧伸出中心粒附属物,中心粒附属物由９条微管组成,９条微管围成一筒状结构,类似轴丝。在晚期精细胞形成精子的过程中,中心粒附属物和近端中心粒相继退缩以至消失不见,同时细胞核后端的形状也随着发生变化。中心粒附属物和近端中心粒的相继消失可以看作是成熟的最后标志。精子的中心粒复合体由基体及其上方的基体帽组成,袖套接于核的后端,其中约有３０～４０个线粒体;鞭毛从袖套腔中伸出,鞭毛的中心结构是轴丝;轴丝外方为细胞质形成的侧鳍,在鞭毛的近核段,轴丝两侧的侧鳍较宽且不对称。     

DISENTANGLING THE EFFECTS OF EVOLUTIONARY, DEMOGRAPHIC, AND ENVIRONMENTAL FACTORS INFLUENCING GENETIC STRUCTURE OF NATURAL POPULATIONS: ATLANTIC HERRING AS A CASE STUDY

The spatial structuring of intraspecific genetic diversity is the result of random genetic drift, natural selection, migration, mutation, and their interaction with historical processes. The contribution of each has been typically difficult to estimate, but recent advances in statistical genetics have provided valuable new investigative tools to tackle such complexity. Using a combination of such methods, we examined the roles of environment (i.e., natural selection), random genetic processes (i.e., drift), and demography and life histories (e.g., feeding migrations) on population structure of a widely distributed and abundant marine pelagic fish of economic importance, Atlantic herring ( Clupea harengus ). Individuals were collected during peak spawning time from 19 spawning locations spanning the region from the western North Sea to the eastern Baltic Sea ( N = 1859, eight microsatellite loci). We carried out separate analyses of neutral and selected genetic variation, which allowed us to establish that the two most important factors affecting population structure were selection due to salinity at spawning sites and feeding migrations. The genetic signal left by the demographic history of herring, on the other hand, seems to have been largely eroded, which is not surprising given the large reproductive potential and presumed enormous local effective population sizes of pelagic fish that constrain the effect of stochastic processes. The approach we used can in principle be applied to any abundant and widely distributed aquatic or terrestrial species.     

林网生态场中玉米主要产量性状和质量性状的研究

本文试用生态场的思想,对林网中玉米（Zeamays)的主要产量性状和质量性状与生态场的内主要生态因子的关系进行了探讨,研究结果表明：林网生态场对玉米产量性状,质量性状的影响因各因子的场量和玉米的生育阶段而,开花期前较高的温度,开花期后较低的地温,最热季节不过高的温度,以及整个生长季中较高的空气湿度是提高玉米生物学产量,穗产量,籽粒产量以及籽粒中粗蛋白积累量必要的生态条件,玉米籽粒中粗脂肪含量主要受乳熟期以前生态场的影响,尤其在穗分化,形成期需较高的空气湿度和较低的地面温度,淀粉含量受生态场的影响较小,所需生态条件是拔节一蜡熟期较低的地温。总之,各时期生态场的性质均可在玉米最终的产量和质量性状中反映出来。     

成人肾恶性横纹肌样瘤的研究:1例报告及文献复习

应用组织化学、免疫组织化学及电镜技术对我国首例成人肾恶性横纹肌样瘤（ｍ ａｌｉｎｇａｎｔｒｈａｂｄｏｉｄｔｕｍ ｏｒ, ＭＲＴ） 进行了研究, 与婴幼儿ＭＲＴ相比本例有以下临床病理特点： （１） 以血尿为早期和唯一症状,肿块缺乏特征性ＣＴ 改变; （２） 光镜下大量ＰＡＳ阳性嗜酸性球形小体多位于细胞外, 电镜下细胞外小体由微丝构成并有界膜包绕; （３） 免疫组化显示肿瘤细胞向神经外胚层、横纹肌和组织细胞多向性分化; （４） 肿瘤侵袭力较低, 高度表达ｎｍ ２３－Ｈ１ 蛋白, 随访１８个月术后化疗效果佳, 提示其恶性度较婴幼儿ＭＲＴ 低。     

背角无齿蚌珍珠囊形成过程的组织学和酶组织化学研究

本文采用Ｈ．Ｅ染色法和酶组织化学方法,对背角无齿蚌珍珠囊形成过程的组织学和酶组织化学的变化情况进行了研究,证实了“初生珍珠囊”的形成和溶解及“次生珍珠囊”的形成,并推没“次生珍珠囊”表皮细胞是由育珠蚌结缔组织转化而来的;观察了育珠手术后九种酶在珍珠囊形成的各个阶段和在珍珠囊和育珠蚌不同部位的变化情况,说明了珍珠囊珙成过程是与复杂的能量代谢,物质代谢及物质转运等有关的生理生化过程。