Changes of Chlorophyll Metabolism During the Albinic Stage of a Wheat Mutant

Changes of chlorophyll metabolism during the albinic stage including both degreening and regreening processes were studied. The results indicated that an decrease of Cato content was nor the cause of mutant degreening, and that the mutant belonged to the total Chl-dificient type. The changes of Chlase activity level indicated that Chi breakdown was not the main factor which led to degreen of the mutant. A greater changes of content of intermediates of Chl biosynthesis during the albinic period δ-aminolevulinic acid (ALA) and porphohilinogen (PBG) were accumulated, but uroporphyrin Ⅲ (Uro Ⅲ ), protoporphyrin IX (Proto IX ), Mg-protoporphyrin IX (Mg-Proto IX ) and protochlorophyll (ide) (Pchl (lide)) were decreased. Specialy during the degreening process Uro Ⅲ was gradually decreased, but an initiation of regreening, the Uro Ⅲ was markedly accmulated. It was proved that there was a blockage in Chi biosynthesis in the mutant, which could be somewhere in the formation of uroporphyrinogen Ⅲ (Urogen Ⅲ ).     

A Selection and Testing Procedure for Comparing Several Experimental Treatments with a Control

We consider a selection and testing procedure for comparing k experimental treatments with a control treatment where the treatments are assumed to be normally distributed with unknown means and a common, unknown variance. Stein‐type sampling is used in the selection phase to screen for an experimental treatment that exhibits evidence of being better than the control treatment and each of the other experimental treatments, where better is defined in terms of the largest mean. In the testing phase, the best experimental treatment is compared to the control using a hypothesis test. If no experimental treatment indicates that it is an improvement over the control during the selection phase, our procedure allows for early termination. We provide definitions of level and power appropriate for our hybrid procedure and compute procedure parameters required to implement our procedure.     

A new scyphozoan from the Cambrian Fortunian Stage of South China

Animals with radial symmetry are abundant in the Cambrian Fortunian Stage of South China, but with relatively low diversity: representatives include Olivooides, Quadrapyrgites, carinachitiids, hexangulaconulariids and Pseudooides. Here, we report a new radial animal, Qinscyphus necopinus gen. et sp. nov., from the Fortunian small shelly fauna of southern Shaanxi Province, South China. Qinscyphus necopinus has a cup‐shaped profile, with slightly raised annuli and five groups of triangular thickenings in pentaradial symmetry. This organism has a comparable morphology to, and thus a close affinity with, Olivooides and Quadrapyrgites, and is interpreted as a coronate scyphozoan. This discovery adds a new crown‐group cnidarian to the Cambrian Explosion.     

早期形态发生:一种解决贻贝科(软体动物门:双壳纲)分类、系统发育和进化问题的方法

作者对贻贝科贝类的幼虫和幼贝期发育阶段形态结构的出现和变化顺序进行了研究,其约60个不同分类单元的个体发生可归纳为4种形态发生类型或模式。主要对3个形态发生区域的阶段形态结构的起源、发育变化和同源性做了研究。其一,即中央区域,开始形成于前双壳Ⅰ期(PD-Ⅰ),在某个分类单元它可以在前双壳Ⅱ期(PD-Ⅱ)和幼贝期(N)形成,而在其它分类单元则在前双壳Ⅱ期、幼贝期和双壳期(D)形成;第二区域,即背部后区,在幼贝期出现;第三区域,即背部前区,出现于双壳期。双壳期背部后区在某个分类单元起源于幼贝期的形态构造,在其它分类单元则可能起源于双壳期的形态构造。与在贻贝分类学上应用的成体特征相比,早期发育阶段中央和背部后区的形态结构显示出很明显的发育顺序或特征变化规律。根据以前人们熟知而尚未应用到分类和系统发育研究中的早期发育阶段形态特征,作者重新修订了Soot-Ryen的现生贻贝科种上阶元分类系统,重新提出了科内系统发育关系。修订的分类系统表明,Scarlato and Starobogatov(1984)提出的贻贝科各亚科由偏顶蛤亚科开始,沿4条系统发育路线演化发展,对应其早期发育阶段的4类形态发生类型或模式。     

华南贵州罗旬纳水剖面宾夕法尼亚亚系各阶之界线

贵州罗甸纳水剖面是研究宾夕法尼亚亚系牙形刺和各阶界线的良好剖面.经详细研究,从石炭系中间界线至石炭-二叠系界线,一个新的牙形刺序列为Gnathodus bilineatus bollandensis(密西西比亚系顶部),Declinog-nathodus noduliferus, Idiognathoides sulcatus sulcatus, Id. sinuatus, Id. corrugatus-Id. pacificus, Neognatho-dus symmetricus, Idiognathodus primulus-Neognathodus symmetricus, Idiognathodus primulus-Neognathodus bassleri, Idiognathoides sulcatus parva, Streptognathodus expansus, Idiognathoides ouachitensis, Diplognatho-dus coloradoensis, Di. ellesmerensis, Gondolella donbassica-Go, clarki, Idiognathodus podolskensis, Swadelina subexcelsa, Sw. makhlina-Sw, nodocarinata, Idiognathodus sagittalis, Streptognathodus cancellosus, St. graci-lis, St. guizhouensis, Idiognathodus simulator, I. nashuiensis, Streptognathodus firmus, St. tenuialveus, St. wabaunsensis和St. isolatus(二叠系)等带.Declinognathodus noduliferus和Streptognathodus isolatus的首次现分别代表宾夕法尼亚亚系和二叠系之底;Diplognathodus ellesmerensis, Idiognathodus sagittalis和J. simula-tor的首现则可分别代表莫斯科阶(Moscovian),卡西莫夫阶(Kasimovian)和格舍尔阶(Gzhelian)之底界.作者较为详细讨论了巴什基尔阶与莫斯科阶以及卡西莫夫阶与格舍尔阶之界线,并认为以Diplognathodus ellesmerensis的首现作为巴什基尔阶(Bashkirian)与莫斯科阶之界线足目前最合适的标志.Diplognathodus ellesmerensis是一易于识别、分布广泛及层位稳定的牙形刺种,其产出又十分接近巴什基尔阶与莫斯科阶的传统界线,因此是划分此界线的良好标志.作者拟推荐纳水剖面为莫斯科阶底界之候选层型剖面,这一界线详细的工作正在大量采样分析和深入研究中,成果将在以后陆续发表.     

盘县大洞古人类遗址的地层和古气候研究

贵州盘县大洞的堆积物,自上而下可以分为3层。大洞主体堆积物为角砾堆积,来源于洞顶灰岩的崩塌,另外有人类遗物以及洞外片流作用带入的泥砂。人类化石、旧石器和哺乳动物化石主要分布在第2层角砾堆积中。堆积物在洞厅各部位均有相应分布,属同一沉积序列。已知的早期人类活动时间大约从260ka．B．P．开始,到142ka．B．P．前后结束,对应于深海氧同位素的第6、7阶段。角砾层下段,发育一套遭强烈溶蚀和风化的堆积物,地球化学分析结果显示其湿热的沉积环境,时间大约在260—180ka B．P．期间,对应于深海氧同位素第7阶段;大洞堆积物在气候变化周期上与黄土、青藏高原冰期序列可以对比。     

Histological and histochemical study on mammary gland of Damascus goats through stages of lactation

This research was carried out on seven Damascus goats, to study the relationship between milk production, during advancing lactation, and the changes in secretory mammary cells frequency and cellular activity. Biopsies were obtained from the mammary gland at the three stages of lactation, early, mid and late, for histological and histochemical studies. The histological structures of the mammary gland showed clear differences between lactation stages—being more developed in the early and the mid stages, compared to the late stage of lactation. The number of the alveolar secretory cells increased from the early to the mid stage of lactation by 12.9% and then was reduced at the late stage by 35.9% from that at the mid stage. The milk yield increased by 51.3% from the early to the mid stage, and then was reduced at the late stage by 71.4% from that of the mid stage. The total sectional areas of plate equal to 1.22 mm²/plate of the alveoli were the smallest during late lactation (0.36 mm²/plate) compared to that during the early and the mid stage of lactation (0.50 and 1.17 mm²/plate, respectively). Numerous loci of alkaline phosphatase enzyme (AP) were apparent on the outer surface of the alveolar secretory cells at the early and the mid stages of lactation—suggesting that this enzyme plays an important physiological role in the apical membrane of the alveolar epithelial cells during lactation. Dense protein staining of these cells as well as increased frequency of DNA expression denote great development and increased numbers of these cells at early and mid stages of lactation. This was accompanied by a high level of milk secretion reaching 939.3 ± 130 and 1421.4 ± 123.4 ml/head/day, respectively. In contrast, at the late stage of lactation, the size of alveoli was reduced and few alveoli showed weak AP activity, weak protein manifestation and the lowest frequency of DNA loci. This coincided with the reduction in milk yield (407 ml/head/day). It could be concluded that the stages of the lactation influence the cell number and activity of the mammary parenchyma.     

准噶尔盆地北缘谢家阶底界—推荐界线层型及其生物—年代地层和环境演变意义

新疆准噶尔盆地北缘铁尔斯哈巴合地层剖面构造简单并含有丰富的晚渐新世及早中新世哺乳动物化石。其中铁尔斯哈巴合组及索索泉组沉积基本连续,两组界线位于剖面米距33m处。依据该剖面中8个层位和相邻的XJ99005剖面中18个层位上采集的化石以及它们的上下关系和生物组合性质,划分出5个哺乳动物组合带,其中两个位于铁尔斯哈巴合组中(铁-Ⅱ带),3个在索索泉组下部(索-Ⅰ,Ⅱ,Ⅲ带)。从剖面的铁尔斯哈巴合组、索索泉组和哈拉玛盖组中以0．5m的间距采集了348组古地磁样品,获得的磁性剖面包含了16个正向带和16个反向带(事件),其中包含了相当于地磁极时间表中C7n～C5E段的完整磁极带。铁-Ⅰ～Ⅱ带与塔本布鲁克哺乳动物群相近,为中国已知位置最西、构成门类和数量最多的一个晚渐新世哺乳动物组合。索-Ⅰ带应为中国目前所知的最晚渐新世的哺乳动物带。早中新世索-Ⅱ带与谢家动物群和蒙古中部渐新世—中新世过渡带D带可以对比。早中新世索-Ⅲ带相当于过去使用的“索索泉动物群”,时代大致与乌尔图动物群相当。根据地磁极时间校正,铁尔斯哈巴合剖面中铁尔斯哈巴合组和索索泉组跨越了从24．5Ma(地磁极时带C7n．2n)到18Ma(地磁极时带C5Dr．2r)大约6．5Ma的时间,岩体平均沉积速率大约为2．5cm/千年。剖面中5个生物组合带的时间跨度大致分别为：铁-Ⅰ带：24．4～24．15Ma;铁-Ⅱ带：23．2～23．1Ma;索-Ⅰ带接近但还未到达渐新世/中新世界线的23．03Ma;索-Ⅱ带：21．9～21．7 Ma;索-Ⅲ带：21．68～21．15Ma。我们推荐将铁尔斯哈巴合剖面作为中国区域年代地层单位谢家阶(期)底界界线层型的一个候选剖面。与谢家阶底界相对应的界线暂定在剖面由底向上40．25m处,对应于地磁极时带C6Cn．2n底界。该界线位于索索泉组内部,索-Ⅰ和索-Ⅱ带之间。根据定义,该界线也分别对应于阿基坦阶、中新统以及新近系的底界,年龄为23．03Ma。文章还讨论了下列问题：1)索索泉组的绝大部分应当和谢家阶以及山旺阶地层对比,仅其底部含有索-Ⅰ带化石组合的部分可与塔本布鲁克阶地层对比。2)在进行生物地层对比时尽量使用不同的索索泉组哺乳动物组合带,传统的“索索泉动物群”仅大体相当于索-Ⅲ带。3)许多过去认为的渐新世哺乳动物分子的生存时代实际上延伸到了早中新世,仅以这些分子的存在,不能说明一个动物群及其地层的确切年代。4)塔本布鲁克动物群及相关的期、阶名为有效名称,具有合法性;该阶底界有待确立。5)如果山旺阶底界(谢家阶顶界)位于地磁极时带C6An．1r底,年代为20．43Ma,相应的界线应位于铁尔斯哈巴合剖面89．25m处,因此,铁尔斯哈巴合剖面中有可能产生谢家阶的单位层型,该阶的地质时间跨度为2．6Ma。6)5个生物带都是以兔形类、啮齿类以及食虫类等小哺乳动物为主要分子,而且同门类的属种问具有相当近的演化关系,说明这个地区从晚渐新世到早中新世的一段时期中,动物群性质没有明显变化,总体上反映了一个从早渐新世以来就比较干旱的环境;渐新世和中新世动物群成分在种一级上仍有明显差异;而相当于谢家动物群的索-Ⅱ带则带有明显的过渡性质。7)从索索泉组的岩性、分布的地理部位以及与甘肃秦安剖面相近的时代和动物群等来看,不排除含有风成沉积物的可能。     

Co-dominance and succession in forest dynamics: the role of interspecific differences in crown transmissivity

Forests that are composed of two or more tree species with similar ecological strategies appear to contradict the competitive exclusion principle. Beech-maple communities are a well-known example of such a system. On a local scale, a number of mechanisms have been proposed to explain the coexistence of these two species. These are reciprocal replacement, external factors that favour alternatively one or the other species and demographic stochasticity. This paper presents and analyses a simple mathematical model that shows that external factors are not an essential requirement for coexistence. Rather, coexistence requires interspecific differences in light transmissivity through the crowns of adult trees. However, all the three mechanisms mentioned above can be interpreted within the framework of the model. Furthermore, many models of forest dynamics make use of shade tolerance as a key feature in describing successional dynamics. Despite its importance, however, shade tolerance does not have a commonly accepted quantitative definition. Here, a simple scheme is proposed where the relationship between shade tolerance, individual traits (growth and survival) and successional status is defined. This might have important implications in understanding the overall dynamics. Theoretical results have been compared with a number of studies carried out in North American forests. In particular, coexistence in beech-maple communities and the relation between shade tolerance and successional status in a beech-hemlock-birch community have been discussed.     

Accuracy and completeness of the New Zealand Cancer Registry for staging of invasive breast cancer

PurposePopulation based cancer registries are an invaluable resource for monitoring incidence and mortality for many types of cancer. Research and healthcare decisions based on cancer registry data rely on the case completeness and accuracy of recorded data. This study was aimed at assessing completeness and accuracy of breast cancer staging data in the New Zealand Cancer Registry (NZCR) against a regional breast cancer register.MethodologyData from 2562 women diagnosed with invasive primary breast cancer between 1999 and 2011 included in the Waikato Breast Cancer Register (WBCR) were used to audit data held on the same individuals by the NZCR. WBCR data were treated as the benchmark.ResultsOf 2562 cancers, 315(12.3%) were unstaged in the NZCR. For cancers with a known stage in the NZCR, staging accuracy was 94.4%. Lower staging accuracies of 74% and 84% were noted for metastatic and locally invasive (involving skin or chest wall) cancers, respectively, compared with localized (97%) and lymph node positive (94%) cancers. Older age (>80 years), not undergoing therapeutic surgery and higher comorbidity score were significantly (p < 0.01) associated with unstaged cancer. The high proportion of unstaged cancer in the NZCR was noted to have led to an underestimation of the true incidence of metastatic breast cancer by 21%. Underestimation of metastatic cancer was greater for Māori (29.5%) than for NZ European (20.6%) women. Overall 5-year survival rate for unstaged cancer (NZCR) was 55.9%, which was worse than the 5-year survival rate for regional (77.3%), but better than metastatic (12.9%) disease.ConclusionsUnstaged cancer and accuracy of cancer staging in the NZCR are major sources of bias for the NZCR based research. Improving completeness and accuracy of staging data and increasing the rate of TNM cancer stage recording are identified as priorities for strengthening the usefulness of the NZCR.