990 resultados para Gray


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The annual catches of four small longliners operating off northeast Brazil from 1983 to 1997 were examined across different areas and locations. The total catch comprised tunas (30%), sharks (54%), billfishes (12%), and other fish species (4%). Fishing strategy and annual composition of catches showed large spatial and temporal variabilities with the dominant catches alternating among yellowfin tuna, Thunnus albacares; gray sharks, Carcharhinus spp.; and blue shark, Prionace glauca. Catches of blue and gray sharks showed a significant interaction among seamounts, with gray sharks occurring in maximum abundance around those seamounts that had relatively deep summits and low-sloping depth profiles. Results are discussed in terms of the various factors that may have influenced distribution of effort.

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Os granitoides do Domínio Cambuci, na região limítrofe entre os estados do Rio de Janeiro e Espírito Santo, foram separados em quatro principais grupos: (1) Complexo Serra da Bolívia (CSB) - Ortogranulitos e Ortognaisses Heterogêneos; Ortognaisse Cinza Foliado; e charnockitos da Região de Monte Verde (2) Leucogranitos/leucocharnockitos gnaissificados da Suíte São João do Paraíso (SSJP) (3) Granito Cinza Foliado (4) Leucogranito isotrópico. O CSB é caracterizado pelo magmatismo de caráter calcioalcalino do tipo I, oriundo em ambiente de arco vulcânico (Suíte Monte Verde) e retrabalhamento crustal (ortogranulitos leucocráticos). O Ortogranulito esverdeado fino, é considerado no presente estudo como rocha do embasamento para o Terreno Oriental, cristalizada durante o paleoproterozoico - Riaciano (2184,3 21 Ma) e recristalizada durante o evento metamórfico Brasiliano no neoproterozoico - Edicariano (607,2 1,5 Ma), cuja idade TDM é de 2936 Ma. O Ortogranulito leucocrático médio cristalizou-se no neoproterozoico Edicariano (entre 592 e 609 Ma) e idade TDM ca. 2100 Ma, ao qual apresenta registro de herança no paleoproterozoico. A Suíte Monte Verde caracteriza-se por um magmatismo calcioalcalino e a Suíte Córrego Fortaleza, por um magmatismo calcioalcalino de alto K, ambas com assinatura de arco magmático. Registram dois pulsos magmáticos, em no Neoproterozoico - Edicarano: um em 592 2 Ma, idade do charnoenderbito, com idade TDM 1797 Ma, e outro em 571,2 1,8 Ma (injeção de um charnockitoide). Para todas as rochas do CSB são registradas feições protomiloníticas, miloníticas e localmente ultramiloníticas. Os dados geoquímicos indicam que os granitoides da SSJP são da série calcioalcalina de alto K, gerados no Neoproterozoico (idades que variam desde 610,3 4,7 Ma até, 592,2 1,3 Ma. As idades TDM revelam valores discrepantes para duas amostras: 1918 Ma e 2415 Ma, sugerindo que tenham sido geradas de diferentes fontes. O Granito Cinza Foliado é da Série Shoshonítica, metaluminoso do tipo I e, de ambiência tectônica de granitos intraplaca. Entretanto, poderiam ter sido fomados em ambiente de arco cordilheirano, havendo contaminação de outras fontes crustais. Fato este pode ser confirmado pelas as idades TDM calculadas ≈ 1429 1446 Ma. O Leucogranito isotrópico ocorre em forma de diques de direção NW, possui textura maciça e é inequigranular. Dados geoquímicos revelam que são granitoides metaluminosos do tipo I da série shoshonítica, e, de acordo com a ambiência tectônica, são granitos intraplaca. O Leucogranito Isotrópico representa o magmatismo pós-colisional ao qual ocorreu entre 80 a 90 Ma de anos após o término do evento colisional na região central da Faixa Ribeira. O Leucogranito Issotrópico cristalizou-se no cambriano (512,3 3,3 Ma e 508,6 2,2 Ma) e com idades TDM ca. 1900

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O objetivo desta pesquisa é verificar se houve aumento de conservadorismo na contabilidade brasileira após a publicação das Leis 11.638/2007 e 11.941/2009.A investigaçãojustifica-se pela importância da análise do nível de conservadorismo e do processo de convergência da contabilidade brasileira. Foram coletados os ajustes de patrimônio líquido e lucro líquido nas demonstrações contábeis dos anos de 2008 e 2009 e a partir deles utilizou-se a metodologia proposta por Gray (1980) para aferição do nível de conservadorismo. A pesquisa é empírica e a amostra foi composta pelas companhias que compuseram a primeira carteira teórica do IBRXem 2013, excluindo do rol as instituições financeiras. Após outras exclusões pertinentes, a amostra ficou constituída por 54 empresas para a primeira fase da transição (2008) e 70 para a segunda fase do processo (2010). A metodologia constituiu na utilização do teste não paramétrico de Wilcoxon, do Teste da Mediana e de estatísticas descritivas. Com base nas métricas construídas e nos testes estatísticos aplicados, concluiu-se que não houve variação estatisticamente significativa no nível de conservadorismo contábil brasileiro com a adoção dos novos padrões contábeis.

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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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翠雀属Delphinium L.是毛茛科中的一个大属,全世界有300-400 余种,广布于北半球温带地区。我国是世界上记载翠雀属植物种类最多的国家,尤以西南横断山区种类最为丰富。 通过文献查阅、标本室研究和野外考察,本文对我国特别是横断山区翠雀属植物的主要形态性状在居群间和居群内的变异式样进行了初步分析,认为根的形态、叶的分裂程度、植株尤其是花序轴和花梗被毛与否以及毛被类型、小苞片的形状和位置、退化雄蕊的颜色、上萼片的形状、心皮数目和种子形态特征是比较可靠的分类性状。但性状之间的相关性往往较小,即使是通常比较稳定的分类性状有时也表现出不同程度的变异,因此同一性状对于不同等级分类群的划分和在不同分类群中的分类价值常不一样。在具体的分类处理中,应具体情况具体分析,尽可能利用较多的分类学性状或性状组合。 根据上述对我国翠雀属植物主要形态性状变异式样的理解,本文主要对我国西南横断山区及其邻近一些地区的翠雀属植物进行了力所能及的分类修订:将42 种和22 变种降为异名,提出2 新组合(毛梗黑水翠雀D. potaninii var. mollipes (W. T. Wang) Q. Yuan & Q. E. Yang 和腺毛康定翠雀D. tatsienense var. pseudomosoynense (W. T. Wang) Q. E. Yang & Q. Yuan),澄清了直距翠雀D. tenii Lévl. 的名实问题和Munz 等学者对我国翠雀属植物标本的鉴定错误以及由此引起的我国有关翠雀属植物的地理分布的混乱; 另有两种( 硕片翠雀D. grandilimbum W. T. Wang & M. J. Warnock 和永宁翠雀D. yongningense W. T. Wang & M. J. Warnock)因未见到模式标本,故暂存疑。本文讨论到的我国翠雀属植物共有87 种、10 变种。 为了在染色体水平上了解横断山区翠雀属植物的物种形成和分化,同时增加对整个翠雀族tribe Delphineae Warming 植物染色体进化的理解,本文报道了我国主要采自该地区的乌头属Aconitum L. 30 种、1 变种共40 个居群和翠雀属 48 种、3 变种共87 个居群的染色体数目,分析了30 种、1 变种乌头属植物和 46 种、3 变种翠雀属植物的核型,发现46 种、3 变种翠雀属植物为二倍体(2n = 2x=16),1 种(黄毛翠雀D. chrysotrichum Finet & Gagnep.)为四倍体(2n = 4x =32),1种(螺距翠雀D. spirocentrum Hand.-Mazz.)有二倍体和四倍体两种细胞型,3 种(宽距翠雀D. beesianum W. W. Smith、裂瓣翠雀D. mosoynense Franch.和康定翠雀 D. tatsienense Franch.)的个别居群有B 染色体出现。这表明横断山区翠雀属植物的物种形成主要在二倍体水平上进行。可能由于核型直向选择(karyotypic orthoselection)的结果,我国翠雀属植物的核型就整体情况而言在属内相当一致,属内核型分化不如乌头属中明显,外部形态上显得最为原始的种类如短距翠雀 D. forrestii Diels 和毛翠雀D. trichophorum Franch.的核型与其他多年生种类的核型相比并无明显区别。尽管如此,翠雀属植物的核型在属内仍表现出一定程度的分化:在多年生种类中,大理翠雀群(D. taliense group)的种类的染色体内部不对称性(intrachromosomal asymmetry) 程度较高, 但染色体之间的不对称性 (interchromosomal asymmetry)程度偏低;一年生种类与多年生种类相比,我国唯一的一年生种还亮草D. anthriscifolium Hance 染色体之间不对称性最高,该种染色体内部不对称性程度在翠雀族中也偏高,因此就其核型的整体不对称性程度而言,在翠雀属乃至整个翠雀族中最高,而地中海分布的一年生种类的染色体内部不对称性明显增强, 但染色体之间的不对称性在翠雀族中最低。这种核型分化的系统学和生物地理学意义尚不清楚,以后需进一步研究。与乌头属相比,翠雀属植物的染色体通常较小,核型中st 染色体明显增多(可达6 对),核型的整体不对称性程度逐渐增强; 虽然乌头属牛扁亚属Aconitum subgen. Lycoctonum (DC.) Peterm.的二倍体种类也一般具有较多的st 染色体(4 对),但这些st 染色体比乌头亚属Aconitum L. subgen. Aconitum和露蕊乌头亚属Aconitum subgen. Gymnaconitum (Stapf) Rapaics 植物核型中相对应的m 或 sm 染色体以及翠雀属和飞燕草属Consolida (DC.) S. F. Gray 植物中相对应的st 或偶尔出现的sm 染色体要大。特别应当注意的是牛扁亚属中外部形态上显得最为原始的展喙乌头A. novoluridum Munz 的核型具有较多而且较大的sm 染色体,所以我们认为展喙乌头的核型保留了较多的原始性质,那些核型中具有较多st 染色体的牛扁亚属植物应当是该亚属中在核型上已比较特化的种类。这一结果不支持前人提出的乌头属植物的核型有从st 染色体进化到m 或sm 染色体的趋势的观点。就整个翠雀族而言,从现有资料看,其核型的进化趋势应当为:(1) 染色体从大进化到小, 从m 或sm 染色体进化到st 染色体;(2) 核型的整体不对称性程度逐渐增强,即核型的二型性从多年生的牛扁亚属植物到翠雀属植物的一年生的还亮草亚属Delphinium subgen. Delphinium 而愈趋明显。翠雀族植物核型的进化方向与整个毛茛科核型的进化方向看来是一致的,即都向核型不对称性增强的方向进化。

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万寿竹属(Disporum Salisbury)隶属于广义百合科广义黄精族(Liliacear s. l.-Polygonateae s.l ),分为Sect. Disporum(东亚,约20种)和Sect. Prasartes(北美,6种)两个组。对于Sect. Disporum,日本的研究者者进行了大量的形态学、细胞学、胚胎学、生态学和物种生物学方面的研究,但研究的地域主要局限于日本和尼泊尔等地,种类也主要是D. sessile(只分布于日本),D. smilacinum(分布于中国烟台,朝鲜,韩国,俄罗斯远东,日本)等中国不产或少产的种,或者在整个东亚都有分布的广布种,如D. cantoniense。对于只分布于中国则涉及很少,如D. bodinieri,D. longistylum,D. megalathum, D. hainanense, D. acuminatissimum, D. jinfoshanense等。尽管Hara于1988年对东亚的Disporum进行了一次系统的修订,但是对Disporum的认识混乱的情况仍然大量存在。因此,正本清源的工作就显得很有必要。 本研究主要包括以下几个方面的内容: a) D.bodinieri的文献考证和标本订正 结合文献考据和标本鉴定两方面的工作,认为D. bodinieri (Lévl. et Vant.) Wang et Tang在Flora of China Vol. 24 (2000)的分类处理,接受了Hara(1988)的观点,但是对国内的标本并没有进行相应的鉴定处理,其仍然被鉴定为D. bodinieri,但这些标本并不属于单一的分类学实体,而是包含D. bodinieri (Lévl. et Vant.) Wang et Tang和D. longistylum (Lévl. et Vant.) Hara两大类群,需作重新鉴定。 D. bodinieri和D. longistylum的形态学性状有很明显的区别,但是在所有被鉴定为D. bodinieri的标本中,真正的D. bodinieri (Lévl. et Vant.) Wang et Tang只占到10%,产生上述问题的直接原因是受到《中国植物志》第15卷(1978)的影响。 b) 发现并描述了一个新种:Disporum jinfoshanense X. Z. Li, D. M. Zhang et D. Y. Hong 该种与山东万寿竹D. smilacinum A. Gray相似,具卵形或椭圆形叶,顶生花序,花被片白色,开展,基部稍具浅囊;不同之处在于其茎高15(-20)cm,叶子3-4片,集中于茎上部,叶柄明显,长2-4mm,花被片内表面密布短柔毛。 c) 基于形态学数据的聚类分析 通过前期的性状研究,文献考证,标本订正以及发表新种,我们获得了大量的形态学数据。为了验证对D. bodinieri标本订正的正确性,我们利用PAUP软件采用UPGMA算法对标准化的形态学数据进行运算。获得的树状图显示:新种D. jinfoshanense和D. viridenscense、D. smilacinum聚在一起,如实反映了形态的相似性,说明该树图可信;被错误鉴定为D. bodinieri的标本和正确鉴定为D. longistylum的标本聚在一起,说明前面的判断是正确的。

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The summer flounder, Paralichthys dentatus, is overexploited and is currently at very low levels of abundance. This is reflected in the compressed age structure of the population and the low catches in both commercial and recreational fisheries. Declining habitat quantity and quality may be contributing to these declines, however we lack a thorough understanding of the role of habitats in the population dynamics of this species. Stock structure is unresolved and current interpretations, depending on the technique and study area, suggest that there may be two or three spawning populations. If so, these stocks may have differing habitat requirements. In response to this lack of knowledge, this document summarizes and synthesizes the available information on summer flounder habitat in all life history stages (eggs, larvae, juveniles and adults) and identifies areas where further research is needed. Several levels of investigation were conducted in order to produce this document. First, an extensive search for summer flounder habitat information was made, which included both the primary and gray literature as well as unanalyzed data. Second, state and federal fisheries biologists and resource managers in all states within the primary range of summer flounder (Massachusetts to Florida) were interviewed along with a number of fish ecologists and summer flounder experts from the academic and private sectors. Finally, information from all sources was analyzed and synthesized to form a coherent overview. This document first presents an overview of the economic importance and current status of summer flounder (Chapter 1). It then summarizes our present state of knowledge of summer flounder distribution, life history patterns and stock identification (Chapter 2). This is followed by a synopsis of habitat requirements during each life history stage. For convenience, this is presented by general habitat as offshore eggs (Chapter 3), offshore larvae (Chapter 4), estuarine larvae (Chapter 5), estuarine juveniles (Chapter 6), offshore juveniles (Chapter 7) and estuarine and offshore adults (Chapter 8). In several instances, previously undigested data sets are analyzed to provide more detailed information, especially for estuarine juveniles. The information is then discussed in terms of its relevance to resource managers (Chapter 9).

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In this paper we will describe new bimesogenic nematic liquid crystals that have high flexoelectro-optic coefficients (e/K),of the order of 1.5 CN 1 m-1, high switching angles, up to 100° and fast response times, of the order of 100μs or less. We will describe devices constructed, using the ULH texture that may be switched to the optimum angle of 45° for a birefringence based device with the fields of 4Vμm-1 over a wide temperature range. Such devices use an "in plane" optical switching mode, have gray scale capability and a wide viewing angle. We will describe devices using the USH or Grandjean texture that have an optically isotropic "field off" black state, uses "in plane" switching E fields, to give an induced birefringence phase device, with switching times of the order of 20μs. We will briefly describe new highly reflective Blue Phase devices stable over a 50V temperature range in which an electric field is used to switch the reflection from red to green, for example. Full RGB reflections may be obtained with switching times of a few milliseconds. Finally we will briefly mention potential applications including high efficiency RGB liquid crystal laser sources. © 2006 SID.

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This working paper is part of a review of aquaculture technologies and gender in Bangladesh in the period 1990 to 2014. It assesses how gender has been integrated within past aquaculture technology interventions, before exploring the gender dimensions associated with current approaches to transferring knowledge about homestead aquaculture technology. It draws out existing knowledge, identifies research gaps, and selects practices to build upon--as well as practices to move away from. The review examines the research and practice of WorldFish and other development partners in Bangladesh through consultations, a review of gray and published literature, and fieldwork. It aims to contribute to the development of aquaculture technology dissemination methodologies that strengthen and underpin women’s participation in aquaculture.

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The first 539 bases of mitochondrial DNA D-loop region of six Chinese native chicken breeds (Gallus gallus domesticus) were sequenced and compared to those of the red junglefowl (Gallus gallus), the gray junglefowl (Gallus sonneratii), the green junglefow

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Melanocortin-1 receptor (MC1R) plays a major role in pigmentation in many species. To investigate if the MC1R gene is associated with coat color in water buffalo, the coding region of MC1R gene of 216 buffalo samples was sequenced, which included 49 black river buffalo (Murrah and Nili-Ravi), 136 swamp buffalo (Dehong, Diandongnan, Dechang, Guizhou, and Xilin) with white and gray body, and 31 hybrid offspring of river buffalo Nili-Ravi (or Murrah) and swamp buffalo. Among the three variation sites found, SNP684 was synonymous, while SNP310 and SNP384 were nonsynonymous, leading to p.S104G and p.I128M changes, respectively. Only Individuals carrying homozygote E-BR/E-BR were black. The genotype and phenotype analysis of the hybrid offspring of black river buffalo and gray swamp buffalo further revealed that the river buffalo type allele E-BR or the allele carrying the amino acid p.104S was important for the full function of MC1R. The in silico functional analysis showed that the amino acid substitutions p.G104S and p.M128I had significant impact on the function of MC1R. Above results indicate that the allele E-BR or the allele carrying the amino acid p.104S was associated with the black coat color in buffalo.