926 resultados para Chilean Mill


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This is the Intensive biological survey of the Glaze Brook catchment May 1981 report produced by the North West Water Authority in 1981. The aim of this report is to identify those pollution problems not identified during the routine biological water quality surveys, and to check the suitability of the routine biological sampling point. This report looks at an intensive biological water quality survey of the Glaze Brook catchment which was carried out by Biol. (S) on 13th-15th May, 1981. Kick samples of invertebrates were taken at 5 sites and all invertebrates were identified and counted in the field. The most significant water quality observations in the report were from: Borsdane brook, Pennington brook, Glaze brook, Amberswood brook, Cunningham brook, Old Mill brook, Shakerley brook, Astley brook and Shaw brook.

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This is the River Gowy rapid corridor survey July 1995: Ecology South Mersey report produced by the National Rivers Authority North West Region in 1995. This report looks at the survey carried out by the South Mersey Ecology Team prior to routine deweeding operations on the main River Gowy at the end of July, 1995. The survey covered Flood Defence Stretch References RGOW03 to RGOW16. These stretches were further divided into a series of 43 stretches, each one being approximately 500m in length for ease o f mapping by Ecology. Recommendations for each length have been cross-referenced with the Bill of Quantities where possible, e.g. retention o f margins. In Flood Defence stretch RGOW03, the South West Winter Wetland forms an important habitat for birds. In stretches RGOW04 to RGOW05, the Gowy Meadows and Ditches have been designated a Grade A, Site of Biological Importance, by Cheshire County Council due to the nature of the acidic grassland and diverse ditches. In stretches RGOWIO to RGOW11 the left bank forms Hockenhull Platts, Grade A Site of Biological Importance and County Trust Reserve. In stretches RGOW15 to RGOW16, the area from Mill Farm to the Shropshire Union Canal is a Grade A Site of Biological Importance. These sites are very sensitive and detailed recommendations for working practices can be found in the relevant sections o f the survey.

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A Resolução CONAMA N 430/2011 exige a utilização de dois bioensaios (dois níveis tróficos) para avaliação ecotoxicológica de efluentes, mas a seleção ao acaso de bioensaios pode permitir lançamentos tóxicos. A sensibilidade dos bioindicadores irá depender da substância tóxica avaliada. Assim, baterias de bioensaios sensíveis devem ser estabelecidas às classes de contaminantes. Na literatura não há estudos que indiquem uma bateria de bioensaios ecotoxicológicos sensíveis para avaliação de efluentes contendo principalmente metais. Esse trabalho teve como objetivo selecionar uma bateria de bioensaios ecotoxicológicos que conjuntamente detectem toxicidade ao maior número de metais isolados e em misturas e que sejam realizados no menor tempo indicado pelas normas de padronização. Foram avaliadas as sensibilidades de seis bioensaios, incluindo três níveis tróficos (produtores, algas: Pseudokirchneriella subcapitata e Chlorella vulgaris; consumidores primários, cladóceros: Daphnia similis e Ceriodaphnia dubia; consumidores secundários, peixes: Poecilia reticulata e Danio rerio), a 10 espécies metálicas individuais (Ag+, Cd2+, Cu+, Cu2+, Cr3+, Cr6+, Pb2+, Ni2+, Zn2+ e Hg2+) e a efluentes reais (siderúrgicos) e simulados em laboratoriais (baseado nos limites máximos permitidos para descarte). Os bioensaios com peixes foram os menos sensíveis, D. rerio não detectou toxicidade em nenhum dos efluentes testados. P. subcapitata foi um bom bioindicador de toxicidade de Cr3+ e D. similis foi o organismo mais sensível a Hg2+. O uso combinado do bioensaio crônico de 72h com C. vulgaris e do bioensaio agudo de 48h com C. dubia garantiu a detecção das menores concentrações dos metais tanto individualmente quanto em efluentes reais e simulados. Apesar de P. subcapitata ser um bom bioindicador da toxicidade de Cr3+, a interação dos metais em misturas tornou C. vulgaris igualmente sensível. Da mesma forma, apesar de D. similis ter sido mais sensível ao Hg2+, o efeito da toxicidade dos efluentes com maiores teores de Hg2+ foi detectado por C. dubia

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Estudos demostram que a hiperalimentação no período pós-natal causa obesidade, alterações cardiometabólicas e resistência à insulina em longo prazo. O objetivo do estudo foi investigar as consequências da hiperalimentação na lactação nos corações de camundongos filhotes e adultos ao longo do desenvolvimento. Para induzir a hiperalimentação na lactação, o tamanho da ninhada foi reduzida a 3 filhotes machos no terceiro dia, grupo hiperalimentado (GH). O grupo controle (GC) permaneceu com 9 filhotes da lactação ao desmame. Avaliamos a massa corporal, gordura epididimária e retroperitoneal, morfologia hepática e cardíaca, ultraestrutura dos cardiomiócitos, peso do PVE/CT, glicemia de jejum, triglicerídeos, colesterol total, insulina plasmática e HOMA-IR. Analisamos o consumo de oxigênio das fibras cardíacas através da respirometria de alta resolução, atividade enzimática da PDH, CS e LDH no coração e glicogênio hepático. Biologia molecular, através das proteínas: IRβ, IRS1, pIRS1, PTP1B, PI3K, Akt, pAkt, GLUT1, GLUT4, AMPKα, pAMPKα, HKII, CPT1, UCP2, FABPm, CD36, PGC-1α, PPARα, 4HNE, complexos da CTE (I, II, III, IV e V), α-tubulina, GP91 e VADC. Diferenças entre os grupos analisadas por Two-Way ANOVA, com significância p<0,05. O GH apresentou aumento da massa corporal, gordura epididimária, retroperitoneal e colesterol total em todas as idades; glicemia de jejum, insulina, índice de HOMA-IR e triglicerídeos aos 21 e 90 dias. Aumento do índice de Lee aos 60 e 90 dias. GH apresentou diminuição: do IRβ e GLUT4 aos 21 e 60 dias; aumento do IRβ aos 90 dias; aumento do IRS1, PTP1B, aos 21 e 90 dias e da AKT, pAMPK/AMPK e GLUT1 aos 21 dias; diminuição da pIRS1/IRS1, PI3K, pAKT/AKT aos 21 e 90 dias; diminuição da HKII aos 21 dias e aumento aos 60 e 90 dias; aumento da PDH aos 90 dias; aumento da LDH aos 21 dias e redução aos 60 dias; aumento da CS aos 21 dias e diminuição aos 60 e 90 dias; aumento da oxidação de carboidratos aos 21 dias e redução aos 90 dias; diminuição na oxidação de ácidos graxos aos 60 e 90 dias. Adicionalmente, aumento do desacoplamento mitocondrial entre a fosforilação oxidativa e a síntese de ATP aos 60 e 90 dias. Diminuição da CPT1 e aumento da UCP2 aos 21 e 90 dias. Diminuição da PGC-1α aos 60 e 90 dias; da FABPm e CD36 em todas idades. Aumento da 4HNE aos 21 e diminuição aos 90 dias. Diminuição na expressão do mRNA para CPT1 aos 21, 60 dias. Diminuição na expressão do mRNA para PPARα e aumento na expressão do mRNA para UCP2 aos 21 dias; diminuição na expressão do mRNA para UCP2 ao 60 dias. Alterações morfológicas cardíacas e hepáticas, assim como na ultraestrutura dos cardiomiócitos, em todas as idades, maior conteúdo de glicogênio hepático aos 21 e 90 dias. Concluímos que a hiperalimentação na lactação levou à obesidade, com aumento da oxidação de glicose, alterações no metabolismo energético associadas à diminuição da sensibilidade à insulina, redução da capacidade oxidativa mitocondrial, levando ao desacoplamento e alteração da morfologia e ultraestrutura dos cardiomiócitos do desmame até a idade adulta.

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本文对桦木科植物的研究历史作了详细的总结;在钻研文献的基础上,补充了部分系统学资料,使得花序、花、花粉、叶表皮等各类性状能够在属间进行比较,根据外类群比较、和谐性分析等原则确定了性状的演化极性,利用最大同步法和最小平行演化法对桦木科植物进行了分支分析;对各属的现代分布和地史分布作了描述,在此基础上,讨论了桦木科植物的分布中心、起源地、起源的时间和散布的途径;在第四章,作者试图回到遥远的晚白垩纪和早第三纪,从描绘桦木科植物起源和早期分化的古地理和古气候背景入手,分析了在这种背景下桦木科植物所发生的空间辐射以及植物体本身所产生的形态进化,以求得对桦木科植物起源、散布和分化作出比较合理的解释;最后对桦木科组以上的等级作了分类处理。全文包括五个部分,主要的结论如下: 1、分支分析:广泛阅读桦木科、壳斗科和南青冈科的文献,详细研究中国科学院植物研究所标本馆所藏的桦木科植物的标本。首先以壳斗科和南青冈科作为外类群对各类性状进行了分析,得到一个由22个性状组成的数值矩阵;接着又对上述的22个性状作了和谐性分析,结果有7个性状的CN>O,2,其中3个性状在调整性状状态后被保留,有4个性状在颠倒极性和调整性状状态后仍不和谐被去除.最后得到由18个性状组成的矩阵,该矩阵和谐性检验的结果是:所有性状的KN值和CN值均为O,将此矩阵用最大同步法和最小平行演化法进行分支分析,得到一个相同的分支图。分支图用了19个演化步数,与矩阵的最小步数相同,较好地反映了桦木科植物的属间关系。分支图说明:桤木属是从桦木科植物的祖先中最早分出的一个分支,几乎保留了祖先所有的原始性状;桦木属和桤木属近缘,但并非姊妹群;榛届在桦木科中占有特殊的地位,是桦木科植物的原始类群向进化类群演化的中间纽带;虎棒子属是榛属向鹅耳枥属和铁木属进化过程中分化出的一支;铁木属和鹅耳枥属为姊妹群,在桦木科植物中演化水平最高。 2、地理分布:地理分布分析是以经典分类、系统发育和古植物学三方面的资料为基础,根据生物进化的时、序、空相互统一的观点来讨论的。 根据Takhtajan (1978)对世界植物系的分区,认为:东亚区分布6属、13组、77种,占桦木科植物全部种类的59%,为第一分布中心;大西洋一一北美区分布5属。8组、20种,为第二分布中心;环北方区分布5属、8组,35种,是桦木科植物分化的重要地区。在中国,根据吴征镒(1979)对中国植物区系的分区,认为:中国一一日本森林亚区和中国一一喜马拉雅亚区在种数,组数和属数的分布上分别位居第一和第二。四川及其毗邻省区分布6属、52种,占全部中国种类的70, 3%,是中国桦木科植物的分布中心。 桦木科最早的化石记录是具多个角萌发孔并有带状加厚的桤木粉,发现于日本桑托期.随之这类花粉和另外一种花粉类型:副桤木粉(有微弱带状加厚的三孔粉)在欧亚大陆和北美的地层中便开始普遍起来;可能的桤木属植物的叶子发现于白垩纪最晚期,而可辨认的果序的记录则开始于古新世. 8孔的具带状加厚的桦粉最早见于日本的坎佩尼期,而缺少带状加厚的拟桦粉最早发现于中国内蒙古的梅斯特利克蒂期,以上两类花粉均和现代桦木属植物的花粉相似;可归于同一个化石植物Betula leopoldae的叶子、雄花序,果序和果实的化石发现于加拿大大不列颠哥伦比亚的中始新世地层中。基于果实化石的榛属植物的最早记录发生在欧洲和北美古新世;被认为和榛属有亲缘关系的绝灭属——古鹅耳枥属的叶子,果序和雄花序的化石发现于古新世和始新世;开始见于中国梅斯特利克蒂期的拟榇粉和最早发现于苏格兰古新世的米勒三孔粉也均和榛属植物有关。基于可辨认的花粉和果苞的化石,鹅耳枥属和铁木属分别在晚始新世和早渐新世有了最早的化石记录. 最后根据化石证据和现代地理分布特征提出:以四川为中心的中国中部地区是桦木科植物起源和早期分化的中心;最早的桦木科植物生活在晚白垩纪桑托期,桤木属、榇属、桦木属可能在白垩纪最晚期或古新世时就已经出现了,而最迟不晚于中始新世;鹅耳枥属和铁木属的形成均不晚于晚始新世,到渐新世时,除虎榛子属外,桦木科其它各属均广泛分布在北半球。 3、进化分析:桦木科植物起源和早期演化的晚白垩纪和早第三纪在古地理和古环境方面主要有四个特点:(1)地球板块相对稳定;(2)气候相对一致,区带环流是大气环流的基本成份; (3)恐龙绝灭,哺乳动物作为传播媒介变得重要起来; (4)风媒和虫媒植物共荣。桦木科植物就是在上述背景下起源的。桤木属蒙自桤木组和桤木组最早从祖先类群中分化出来,接着一方面较缓慢地向欧洲散布,并在古新世到达欧洲;另一方面,向中国东北地区散布,然后迅速地扩散到了北极地区,通过白令陆桥在白垩纪最晚期到达了北美。从北美西北部和从欧洲通过大西洋北极陆桥散布到北美东部的桦木科植物在始新世时汇合,形成第二个分化中心。虎榛子属、鹅耳枥属和铁木属植物的大量分化很可能是从全球气候恶化的渐新世开始的,并在分化的同时伴随着其它的桦木科植物向南迁移。桤木属在渐新世时就散布到了当时位于中国东南部的加里曼丹岛;桤木属、鹅耳枥属和铁木属中新世时散布到了墨西哥和中美洲;第四纪冰期加速了桦木科植物的南移,桤木属到达非洲北部和南美洲,桤木属和鹅耳枥属到达台湾岛均发生在更新世。 在环境的选择压力下,桦木科植物经历了一系列的形态演化,作者将这些演化归纳成34个进化趋势。为了对桦木科植物可能祖先的大概轮廓有一个认识,我们又从34个进化趋势中总结出桦木科植物的11个原始特征,并且认为这些特征中的大多数应该是它的祖先拥有的。 (1)裸芽有柄。 (2)气孔器为轮列型或无规则型。 (3)木材具管胞,导管有螺旋加厚,为梯状穿孔。 (4)雌、雄花序共生成总状花序,雄花序位于上部。 (5)花序两性。 (6)雄花序有梗、裸露过冬。 (7)小聚伞花序由多个花组成,苞片多数。 (8)花两性,有花被,子房3室。 (9)花药药室木分离,花丝也不分叉。 (10)花粉粒4-5孔;孔具孔室;孔间有带状加厚;外壁较厚,在孔处翘起并加厚。 (11)具翅坚果小型。 本文提出桦术科植物不可能起源于现存的壳斗科植物,而两者有可能共祖,它们共同的祖先和正型粉类复合群有关,可能来源于正型粉类复合群的某些成员,那么‘正型粉类复合群是否就是金缕梅目和壳斗目进行的中间链环呢?’本文仅作为一个问题提出,而未作回答。 4、系统分类:根据分支分析和表征分类的结果,桦木科是非常自然的一个类群,科内表现出从原始到高级的演化次序并具有三条主要的演化路线。因此,将桦木科划分为三个族与科内的三条演化线相一致,比较符合其属间的系统发育关系。按照各属的变异程度,进一步在桦木族和鹅耳枥族之下分别设立两个亚族。此外在桦木科植物属之下共确立了13个组。桦木科组以上的系统排列为: Betulaceae S. F. Gray Trib. 1. Betuleae Subtrib. 1. Alninae Z. D. Chen subtrib. nov. Alnus Mill. Sect. 1. Clethropsis ( Spach ) Endl. Sect. 2. Alnus Sect. 3. Cremastogyne H. Winkl, Sect. 4. Alnobetula W. D. Koch Subtrib. 2. Betulinae Betula L. Sect. 1. Betulaster ( Spach ) Regel Sect. 2. Betula Sect. 3. Costatae Regel Sect. 4. Chinenses ( Nakai ) Z. D. Chen comb. et stat.nov. Sect. 5. Humiles W.D.Koch Trib. 2. Coryleae Aacheraon Corylus L. Sect. 1, Acanthochlamys Spach Sect. 2. Corylus Trib. 3. Carpineae A. DC. Subtrib. 1. Ostryopsinae Z. D. Chen subtrib. nov.Ostryopsis Dence. Subtrib. 2. Carpininae Ostrya Scop. Carpinus L. Sect. 1. Distegocarpus ( Sieb. et Zucc. ) Sarg. Sect. 2. Carpinus

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根据现有记载,萱草属约有20种,主要分布在东亚,由于种间在外部形态和核型上的高度相似性,加之长期人工栽培,使本属植物的分类成为一个难题,我们做了大量的野外调查和温室栽培试验,获得了一些有意义的观察结果,对核型变异做了详细定量分析:系统观察了花粉扫描电镜特征,为了揭示属内可能的表征和分支关系,运用聚类分析,主成分分析及简约分析对属下类群做了定量研究.本文得到如下主要结论. 1.虽然迄今为止许多核型观察结果未能得到有分类学意义的结论,运用数量分析方法比较各分类群核型定量变异结果表明,其分类学意义是明显的,例如,北黄花菜、黄花菜和小黄花菜三者外部形态很一致,核型亦高度相似:大苞萱草和多花萱草的核型公式虽与前三者相同,但已出现明显的数量变异.同样,北萱草,折叶萱草和西南萱草虽有相同核型公式,亦出现明显数量变异.萱草则与所有其他类群的核型均有明显差别.核型对称性分析表明,臂比不对称性出现一个由低到高的演变序列:但长度不对称性与此无明显相关性.萱草和折叶萱草的臂比不对称性最低,西南萱草和北萱草升高,黄花菜,大苞萱草和多花萱草等最高. 2.观察到三种类型花粉;舟形具网纹,舟形具疣纹和亚球形具疣纹.萱草,北萱草,大苞萱草,北黄花菜,黄花菜,小黄花菜及多花萱草具第一种类型花粉;折叶萱草和西南萱草具第2种类型花粉;矮萱草具第三种花粉.以广义百合科其他类群作为复合外类群进行比较,推测花粉形态的演化序列为:舟形具网纹一舟形具疣纹一亚球形具疣纹. 3.在外部形态上,萱草因具二叉分枝花序,叶型苞片,根膨大适中,花蕾顶部绿色及花筒占花被比例较小等原始性状状态,结合不对称性较低的核型特征和舟形具网纹花粉特征,是现存种类中最原始类群;折叶萱草及北萱草等具较短的花筒,二叉分枝花序,单色花被及花蕾部绿色等特征显得进化程度不高.黄花菜因具夜间开花习性,长花筒,叶鞘红色等状态被认为是进化类群,大苞萱草高度压缩的花序形成头状花序,具总苞状宽大苞片及绳索状根被认为是特化类群,矮萱草个体矮小,单花,具亚球形疣纹花粉亦被认为是高度特化类群.外部形态,花粉特征,核型及地理分布之间存在着相关性;随地理水平分布由南向北,外部形态特征由原始到进化,核型不对称性由低到高:随地理垂直分布由低向高,形态特征由复杂到简化,核型不对称性由低到高,花粉形态由舟形具网纹到舟形具疣纹再到亚球形具疣纹,这两种趋势结合起来构画出了本属植物演化和地理分布的基本轮廊. 4.萱草是一个孤立的属,没有明确的外类群可供比较.在现存类群中.Dahlgren等(1985)认为本属与分布在非洲,地中海地区,西亚及中亚的Asphodeloideae(亚科)有较多的共有特征.本文比较了两个类群之后发现,萱草不但在许多一般特征上与Asphodeloideae -致,而且在小孢子同时型发生及含蒽醌等被认为是Asphodeloideae典型属性的特征上亦与后者相同.这些共有特征显示出二 者在系统发育上一定的联系.进一步比较发现两者在有差异的特征中,萱草属显得较为进化.二者的分布区是完全不同的;Asphodeloideae分布在中亚及其以西地区和非洲,而本属分布在东亚,延及西伯利亚,据本文分析,欧洲生长的一个种(H.lilioasphodelus,北黄花菜)是归化类群.北美和台湾没有自然分布,但栽培植物均生长良好,而且已有归化植物.由此似乎可以推测,本届的祖先与Asphodeloideae的祖先有亲缘关系,这种关系似可远溯到第三纪古地中海时期,或许当时与Asphodeloideae祖先有关系的一个分支分布于古地中海东南缘的康滇古陆,即与现今横断山地区相应的地区,由于喜玛拉雅造山运动引起的地质,地理和气候剧变,某些类群灭绝了,一个类群发展成现今的萱草属. 5.由于本属各分类群间形态及核型相似性程度较高,种间极易(人工)杂交,似无必要在属与种间增设组或系,根据本文研究结果及参考有关分类文献(国外种类),我们将萱草属处理为10种2亚种13变种:H.darrowiana Hu;小萱草(H.dumortieri Morr.)及北萱草(var. esculenta (Koidz.) Kitamura;西南萱草(H.forrestii Diels);萱草(H.fulva (L.) L.)及var. aurantiaca (Baker) Hotta, var. disticha (Donn.) Baker,重瓣萱草(var. kwanso Regel),var. littorea (Makino)Hotta,长菅萱草(var. longituba (Miq.) Maxim,var. maculata Baroni,var. pauciflora Hotta et Matsuoka, var. rosea Stout, var. sempervirens (Araki) Hotta; H. hakuunensis Nakai;北黄花菜 (H. lilioasphodelus L. Var. lilioasphodelus)及黄花菜(ssp. citrina (Baroni) Xiong),小黄花菜(ssp. minor(Mill.) Xiong),var. corcana (Nakai) Xiong;大苞萱草 (H. middendorfii Trautv. et Mey var. middendorfii)及var. exaltata (Stout) Kitamura,长苞萱草(var. longibracteata Xiong);多花萱草(H. multiflora Stout);矮萱草(H. nana Smith ct Forrest);折叶萱草(H.plicata Stapf)。

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球果类植物是现存裸子植物中最为繁盛的一群,也是目前组成北温带森林植被的重要成分,我国是球果类植物科属的重要分布、分化或保存中心。对这些科属的分类和系统发育的研究,无疑对北温带的森林植被的研究,以及林业生产均具有重要的理论和实用价值.本研究即是围绕着球果类中的Pinaceae,Taxaceae及Cephalotaxaceae等科展开的研究,内容主要包括以下几方面: 一、在《中国植物志》第七卷的基础上,完成了《FLORA OF CHINA》中裸子植物Ginkgoaceae,Arancariaceae Pinaceae,Taxaceae,和Cephalotaxaceae各科的修订和编写. 建立2个新种、2个新变种、12个新组合、64个新异名、2个新分布,2个新启用名,分类群及其名称的变动和增补,以及增补异名57个。 二、根据植物的地理分布与系统发育统一的原理,在资料分析和实验的基础上,运用表征分析和分支分析研究方法,同时结合化石和地史资料,针对松科的分类、地理分布、以及起源分化和扩散等问题进行了一系列系统的研究,主要结论如下: 1.提出松科分类的新系统,将松科划分为三个亚科:松亚科Subfam.Pinoideae:仅一属Pinus Linn.: 落叶松亚科Subfam.Laricoideae Melchior&Werderm, emend.N.Li et L.K.Fu:包括四属Larix Mill.,Cathaya Chun&Ku:tng, Picea A Dretr. andPseudotsuga Carr.;冷杉亚科Subfam.Abietoideae Pilger, emend.Frankis:包括五属Abies Mill.,Cedrus Trew, Pseudolarix Gord.,Keteleeria Carr.,and Tsuga Carr. 2.构思和绘出了以地质年代为纵座标的松科系统发育树。 3.进行松科植物分区,将松科划分为6区、4亚区。并分别附有分区图、各区所分布种数的统计表、以及各属目前的地理分布和化石分布图。 4.松科在地质时期曾是一个很庞大的类群,现代松科只是其祖先中少部分喜温性分支的后裔,其兴旺与温带成份的出现关系密切,可能是一类衍生类群. 5.松科的起源时间虽然可追溯到侏罗纪甚至三迭纪,但现代松科各属的出现时间大约是在早白垩纪至第三纪之间。 6.松科各属可能并非起源于同一时间和地点。松属可能是现存的、最早分化出来的类群,于侏罗纪至早白垩纪间起源于欧美古陆;其它属则到晚白垩纪至第三纪早期(有1-2属至中期)才陆续从其祖先复合体中分化出来。 7.现代松科的早期扩散可能存在着以下三条主要的迁陡路线,即:欧美路线、欧亚路线和古白令路线.

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本论文包括两部分的内容,第一部分是秦岭苔类植物的区系研究,第二部分是中国剪叶苔属Herbertus的分类学修订。 秦岭位于我国的中部,东经104º30´~112º52´,北纬32º50´~34º45´N,约76 500 km2。它主要位于陕西省的南部地区,并包括了河南、甘肃和湖北的部分县、市。秦岭的最高峰是太白山,海拔3 767米。秦岭是长江和黄河的分水岭,也是我国温带和亚热带气候的过渡地带。 本研究包含了对自19世纪开始对秦岭苔藓植物的主要采集活动的回顾,和截止2008年以来对秦岭苔类和角苔类植物报道的总结和分析,且首次给出了一份秦岭地区详细的苔类植物的名录,并包括了各个种在秦岭地区的详细分布。根据目前的研究,现已知秦岭的苔类植物有226种(包括种下单位,以下同),其中角苔纲1科3属6种,苔纲30科59属220种;提出了1个新异名:Radula constricta Steph.被处理为Radula lindenbergiana Gottsche var. atypa Massalongo的异名;并提出了1个新组合Metzgeria pubescens var. kinabaluensis (Kuwah) F.X. Li & Y. Jia;发现秦岭新分布的苔类有78种。根据种数,秦岭地区苔类的优势科为光萼苔科(34种),其次为耳叶苔科(23种),裂叶苔科(23种)和羽苔科(19种)。 通过对这些种地理成分的统计,发现秦岭苔类的地理成分以北温带成分为主,占35.05%;其次是东亚成分占到31.78%,这两种地理成分在秦岭占了很大比例,高达66.83%。热带成分相对较少,有22种,占到10.29%。对于苔类来说,中国特有成分在秦岭地区较多,已知有34种,占到15.89%。说明秦岭地区苔类地理成分以温带为主,热带成分占少量比例,且秦岭地区的特有性也比较高。 文章第二部分是对中国剪叶苔属Herbertus S. Gray的分类学修订。剪叶苔属隶属于剪叶苔科,是一个古老而自然的类群,广泛分布于热带和南北温带地区。剪叶苔属植物由于其叶横生或近于横生,侧叶2裂,腹叶2裂或部分不对称3裂,并具假肋,叶细胞具大的三角体而明显区别于苔类的其它属。虽然这个属的概念比较清楚,但在属内种间的划分上存在较大的问题,是苔类中分类较混乱的一个类群。剪叶苔属种的概念多基于叶片形态,包括裂瓣的顶端细胞和假肋的形态及叶基盘边缘附属物的形态。但这些形态特征具很大的可塑性,性状不稳定,造成该属种的概念很模糊。目前全世界剪叶苔属约100余种。中国剪叶苔属的种类尚不确定,《中国苔藓志》中报道了中国有25种l亚种,但Juslen在2006年对亚洲剪叶苔属的修订中,提到中国分布的仅有6种。二者的研究中都存在有一些疏漏和不足之处,对有些种还有争议;且他们的研究中引证的标本都很少,不能全面反映中国剪叶苔属的种类和分布情况。 本研究着手于中国的剪叶苔属,从模式标本入手,从模式标本入手,结合对前人文献中引证标本的查阅,并检视了全国各大标本馆收藏的大量该属的普通标本,对于分类归并上有争议的种,采用扫描电镜和分子生物学的手段进行实验性的研究,对中国的剪叶苔属进行一个全面系统的分类学修订。期望通过本研究,明确中国剪叶苔属的种类和分布情况,为东亚乃至世界剪叶苔属的分类修订提供一份翔实的资料。共查阅了剪叶苔属26个种的模式标本,并检视了中科院北京植物研究所、华南植物园和深圳仙湖植物园馆藏的大量该属植物标本,约600余份。 通过本研究,提出2个新异名:将H. buchii Juslén和H. longispinus var calvs Massalongo处理为H. dicranus (Taylor) Trevis.;将樱井剪叶苔H. sakuraii (Warnst.) S. Hatt.(原并入H. dicranus)和H. minimus Horik.(原并入H. dicranus)重新提出;发现1个中国新分布:H. setigerus (Steph.) H. A. Mill.;确认中国的剪叶苔属17种1亚种:剪叶苔H. aduncus (Dicks.) Gray,剪叶苔纤细亚种H. aduncus subsp. tenuis (A. Evans) H. A. Mill.et E. B. Bohrer,H. armitanus (Steph.) H. A. Mill.,南亚剪叶苔H. ceylanicus (Steph.) Abeyw.,长角剪叶苔H. dicranus (Taylor) Trevis.,高氏剪叶苔H. gaochienii Fu,广东剪叶苔H. guangdongii P.J. Lin & Piippo,卵叶剪叶苔H. herpocladioides Scott. et. Miller,红枝剪叶苔H. huerlimannii Miller,细指剪叶苔H. kurzii (Steph.) H. A. Mill.,长肋剪叶苔H. longifissus Steph.,长刺剪叶苔H. longispinus Jack et Steph.,H. minimus Horik.,长茎剪叶苔H. parisii (Steph.) H. A. Mill.,多枝剪叶苔H. ramosus (Steph.) H. A. Mill.,樱井剪叶苔H. sakuraii (Warnst.) S. Hatt.,短叶剪叶苔H. sendtneri (Nees) Lindb.和H. setigerus (Steph.) H. A. Mill.。本研究还在扫描电镜下观察了H. armitanus、长角剪叶苔H. dicranus和多枝剪叶苔H. ramosus的孢子形态。对于剪叶苔属的修订,还需要更多模式标本的借阅,随着研究深入,剪叶苔属的种类可能会有大量的减少,中国剪叶苔属的种类也将会有一定的减少。

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从栽培蕃茄(Lycopersilon esculentum Mill.)和秘鲁蕃茄(L. peruvianum Mill.)叶子中提取核DNA用EcoRI、BamHI、 HindⅢ限制性内切酶酶切,经Southern转移与digoxigenin标记的渗透调节蛋白cDNA探针进行杂交。从杂交图谱上可以看出两种蕃茄中都至少有两类渗调蛋白基因,同时两种蕃茄在杂交图谱上有差异。栽培蕃茄核DNA经HindⅢ酶切后的5kb和10kb两个片段从电泳凝胶中回收,插入到puc-19载体质粒中,宿主菌为JM109。然后以渗调蛋白cDNA为探针,进行菌落原位杂交,得到几个阳性克隆。

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采用PEG/DMSO融合法,从普通烟草(Nicotiana tabacum L.cv.Xanthi nc)叶肉和毛曼陀罗(Datura innoxia Mill.)茎或叶愈伤组织原生质体融合获得I5株花盆中健康生长的族间体细胞杂种植株;其中11株是在没有选择压力的条件下获得,4株则是在有IOA和R6G选择系统存在下获得。同时获得一株试管开花且形态异常的植株和一株花盆中生长的嵌合植株。lOmM IOA和I5μ g/ml R6G均能分别有效地抑制烟草叶肉和毛曼陀罗愈伤组织原生质体的分裂;10% DMSO能显著提高原生质体融合率;PEG种类并不重要,但浓度则很重要;BAP较ZT,KT对植株分化有更好的诱导效果。杂种的形态、细胞、同工酶、Southern杂交,花粉育性分析结果如下:1、l5株杂种较双亲普遍株型矮小,生长缓慢,形态接近烟草但不很正常,根据形态特征可分为两种类型:(1)共有8株,其叶片大小、形状、颜色、开花习惯、花类型(单花)等均与毛曼陀罗接近,但子房败育;(2)共有7株,其株型、叶片形状、颜色、光滑度、花形状、类型(圆锥状花序)、颜色更接近烟草,但少数杂种开单花或先单花后圆锥状花序或先单花后两种花并存,且开花时间不一,部分子房败育。2、杂种染色体数目大都在60~90之间,个别者较少(48条)或较多(125条),没有一株为双二倍体(2n=96),并全部为混倍体。3、15株杂种植株均有双亲的细胞色素氧化酶同工酶特征谱带;大部分都有双亲的过氧化物酶同工酶特征谱带,少都仅具烟草的谱带。4、Hae Ⅲ/水稻rDNA的Southern杂交分析表明杂种1较双亲多一条谱带,杂种2较双亲也多一条弱带,其它杂种尚待定。5、花粉活力测定表明毛曼陀罗(种子再生而来)的为99%,烟草(原生质体再生而来)为80~90%,而杂种的为24~61%,育性普遍低于双亲。

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本文探计了北京怀柔山区坡积黄土上的次生的荆条(Vitex qhinensic Mill)灌丛的生物量的季节变化规律和元素钾、钙、钠、锌在荆条灌丛中的分布的季节动态及循环特征,并通过相对稳定性指数的求算,对荆条灌丛生态系统的稳定性作出了客观的评价。 荆条的年第一性净生产量为5662.5公斤/公顷•年,其中81.4%来自其根系的生长,枝条的贡献只占13.9%。荆条根系的最高生长速度出现在5~7月,日均增长量为49.7公斤/公顷•天;而枝条的最高生长速度出现在7~10月,日均增长量达8.69公斤/公顷•天,说明光合作用产物首先运往根系,用于根系的生长并积累于根系,尔后才用于枝条的生长。同样,从生物量的动态可以知道光合作用在根系的分配是首先积累于根球,再运往其他部分,在枝条则首先积累于枝条项端。 四种元素在荆条植物体内的浓度的分布,基本上呈一致的规律:生命活动旺盛的部位浓度高,反之就低。钾是荆条中浓度最高的元素,其次是钙、钠、锌。荆条对元素的年吸收量,则是钙最大(60.94公斤/公顷•年),钾次之(40.64公斤/公顷•年),钠为0.3574公斤/公顷•年,锌最小,为0.081公斤/公顷•年。荆条对元素的利用率,为钙1.3 > 钾0.84 > 锌0.85 > 钠0.38。荆条对元素的吸收系数也呈相同的规律。荆条每年因雨水冲失凋落物而损失的元素量仍是钙 > 钾 > 钠 > 锌,而每年因降雨而得到的元素输入则为钾(35.17 公斤/公顷•年) > 钙(31.89) > 钠 (20.64)> 锌。 从荆条灌丛生态系统中钾、锌的循环得出的相对稳定性指数表明该系统是渐进稳定的,但这种稳定性是和人为干扰密切联系。而且该系统离稳定状态尚有较长的距离。

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A mechanical model of cold rolling of foil is coupled with a sophisticated tribological model. The tribological model treats the "mixed" lubrication regime of practical interest, in which there is "real" contact between the roll and strip as well as pressurized oil between the surfaces. The variation of oil film thickness and contact ratio in the bite is found by considering flattening of asperities on the foil and the build-up of hydrodynamic pressure through the bite. The boundary friction coefficient for the contact areas is taken from strip drawing tests under similar tribological conditions. Theoretical results confirm that roll load and forward slip decrease with increasing rolling speed due to the decrease in contact ratio and friction. The predictions of the model are verified using mill trials under industrial conditions. For both thin strip and foil, the load predicted by the model has reasonable agreement with the measurements. For rolling of foil, forward slip is overestimated. This is greatly improved if a variation of friction through the bite is considered.

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Papermaking is considered as an energy-intensive industry partly due to the fact that the machinery and procedures have been designed at the time when energy was both cheap and plentiful. A typical paper machine manufactures a variety of different products (grades) which impose variable per-unit raw material and energy costs to the mill. It is known that during a grade change operation the products are not market-worthy. Therefore, two different production regimes, i.e. steady state and grade transition can be recognised in papermaking practice. Among the costs associated with paper manufacture, the energy cost is 'more variable' due to (usually) day-to-day variations of the energy prices. Moreover, the production of a grade is often constrained by customer delivery time requirements. Given the above constraints and production modes, the product scheduling technique proposed in this paper aims at optimising the sequence of orders in a single machine so that the cost of production (mainly determined by the energy) is minimised. Simulation results obtained from a commercial board machine in the UK confirm the effectiveness of the proposed method. © 2011 IFAC.

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Ring rolling is an incremental bulk forming process for the near-net-shape production of seamless rings. This paper shows how nowadays the process design and optimization can be efficiently supported by simulation methods. For reliable predictions of the material flow and the microstructure evolution it's necessary to include a real ring rolling mill's control algorithm into the model. Furthermore an approach for the online measurement of the profile evolution during the process is presented by means of axial profiling in ring rolling. Hence the definition of new ring rolling strategies is possible even for advanced geometries.

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A process is presented for the forming of variable cross-section I-beams by hot rolling. Optimized I-beams with variable cross-section offer a significant weight advantage over prismatic beams. By tailoring the cross-section to the bending moment experienced within the beam, around 30% of the material can be saved compared to a standard section. Production of such beams by hot rolling would be advantageous, as It combines high volume capacity with high material yields. Through controlled variation of the roll gap during multiple passes, beams with a variable cross-section have been created using shaped rolls similar to those used for conventional I-beam rolling. The process was tested experimentally on a small scale rolling mill, using plasticine as the modelling material. These results were then compared to finite element simulations of individual stages of the process conducted using Abaqus/Standard. Results here show that the process can successfully form a beam with a variable depth web. The main failure modes of the process, and the limitations on the achievable variations In geometry are also presented. Finally, the question of whether or not optimal beam geometries can be created by this process Is discussed. © 2011 Wiley-VCH Verlag GmbH & Co. KGaA. Weinheim.