Équation de production: adaptation du modèle de Ricker à un stock de poissons exploité par différents engins

The authors have developed the method used by Pianet and Le Hir (Doc.Sci.Cent. ORSTOM Pointe-Noire, 17, 1971) for the study of albacore (Thunnus albacares) in the Pointe-Noire region. The method is based on the fact that the ratio between unit of effort and number of fish for two fishing gears is equal to the ratio of their catchability coefficients.

Récolte et traitement des données statistiques de la pêche des palangriers asiatiques dans l'Atlantique

The authors report on the computer programmes developed in the Oceanographic Research Centre of Abidjan for the collection and treatment of statistical data on the fisheries of the asiatic trawlers in the Atlantic. They provide yield by boat, by fishing sector (5 degrees x 5 degrees) and by 15 days fishing in the Atlantic.

Biologie de Penaeus duorarum en Côte d'Ivoire. 3. Étude des variations quotidiennes des rendements et leur relations avec l'hydroclimat. Essai de généralisation au Golfe de Guinée

Hydroclimatic conditions in the Gulf of Guinea between Senegal and Nigeria are briefly described emphasizing the seasonal variations of transparency. Analysis of the Abidjan based shrimp fleet allowed to the description of the seasonal variations of activity rhythms for Côte d'Ivoire, Ghana, and Nigeria. These rhythms are different between seasons, between fishing grounds, and sometimes even between depths on a given ground. These variations follow the turbidity ones. Diurnal activity is observed in very turbid waters, nocturnal and transition activity in clearer ones. The authors assume that the basic behaviour is a nocturnal one, but that the shrimp-trawlers catches reflect some apparently different ones resulting from diel variations in the stock availability. To explain the apparently diurnal behaviour observed most of the year over the whole Gulf of Guinea it is suggested that these generally benthic shrimps become nectonic at night when turbidity is very high. The results obtained in Ivory Coast, Ghana and Nigeria are compared to those from Senegal where hydroclimatic conditions are different. The similarities are emphasized. The differences in observed behaviour are supposedly caused by the cold season water temps which are sufficiently low to disturb the nor mal activity rhythm.

Estimation de la production zooplanctonique sur le plateau continental ivoirien

An attempt was made to calculate zooplankton production from weights and settled volumes and from the life cycle of some copepods. Biomass data were recorded during several years from 24 monthly cruises and from a coastal station sampled biweekly. Dry weight data were directly measured or were calculated from the settled volumes using a linear regression. They range, on an average, from 0.965 to 5.56 g m-2 day-1 from the shore line to the edge of the continental shelf. The mean life-span of the cohorts of 12 species of copepods is about 20 days. It is assumed that only 1 spawn occurs per generation-time and that the standing stock is turned-over during the life span of a cohort. The production ranges from 48.2 to 278 mg dry weight m-2 day-1 or 17.9 to 103 mg C m-2 day-1, according to the depth of the studied areas. One third of carnivorous production occurs among the copepods. So, it is assumed that the herbivorous and omnivorous production is about 2/3 of the total zooplanktonic production. This would be a more accurate estimate of secondary production. The standing stock of zooplankton and fishes are in the same order of magnitude; the ratio zooplanktonic production/total fishery is 0.8%.

Qualitative and quantitative aspects of the food of Ethmalosa fimbriata (Bowdich) in the Ebrié lagoon (Côte d'Ivoire)

The food of Ethmalosa fimbriata in the central part of the Ebrié lagoon, where the salinity is low, consists on limnic phytoplankton. In the region near Abidjan, which is more strongly influenced by coastal water, it consists of marine phyto- and zooplankton. The daily ration of a 12.5 cm fork-length fish is estimated to be between 2 and 3 % of its body weight.

Le courant de Lomonosov dans le fond du Golfe de Guinée en mai 1973

A cruise of the R. V. Capricorne in May 1973, in inner part of the gulf of Guinea, allowed the authors to identify the main part of the Atlantic circulation at the longitude of 5 degrees E, between 4 degrees N and 4 degrees S. It gave new data on the termination of the equatorial undercurrent. At the equator, under the westward south equatorial current flows the Atlantic equatorial undercurrent with a maximum eastward velocity of 90 cm/sec at 30 m depth linked to a salinity maximum higher than 36.20 ppt. Below the equatorial undercurrent, about 80-100 m depth, flows a westward current with a velocity as high as 30 cm/sec. At 4 degrees S, the south equatorial countercurrent is well delineated by a high salinity core (more than 36.10 ppt) at 30 m depth with an eastward velocity core of 40 cm/sec. On the contrary, near 3 degrees 30N, a high salinity core (36.10 ppt) flows westwards with a speed of 40 cm/sec at 40 m depth: it is the "return flow" of the undercurrent (Hisard and Moliere 1974). At 4 degrees N the Guinea current carries eastwards surface salinities of 34.50 ppt at 40 cm/sec. Off Cape Lopez (0 degrees 35'S-8 degrees 42'E) the high salinity core of the undercurrent becomes wider near the shore. It is 25m wide offshore, and 70 m wide near the cape. A part of undercurrent water extends northwards, then flows westwards with the subsurface westward circulation in the inner part of the Gulf of Guinea. Another part flows south-southwestwards in a high salinity tongue along the African coast to 4 degrees S. South-west of Cape Lopez, the trades divergence contributes to an upwelling of cold and high salinity water; this water increases at the Cape Lopez front.

Aspects of the biology and population dynamics of freshwater mussels in Lake Kariba and Lake McIlwaine

The essential aim of this study was to provide a broad foundation of biological knowledge upon which a programme of mussel utilization and management could be built. Results of the study are presented in three main sections. Part 1 describes the stock of Lake Kariba and Lake McIlwaine; part 2 describes various aspects of the breeding biology of the three species; and part 3 presents the results of morphological, biochemical and age analyses - aspects which are used for initial standing crop and production calculations. The final discussion concludes the thesis with a general examination in ecological terms of the factors which have influenced the development and nature of the mussel faunas of the two lakes under consideration.

A implantação do sistema gerencial de custos (SISCUSTOS) desenvolvido pelo Exército Brasileiro: estudo de caso na 1 Inspetoria de Contabilidade e Finanças do Exército

A implantação de sistemas de custos no setor público tem sido apontada como uma necessidade gerencial primordial para se alcançar as dimensões dos princípios da eficiência, eficácia e efetividade na administração pública, fato que proporcionaria a otimização do uso dos escassos recursos disponíveis. Com o advento da Lei de Responsabilidade Fiscal entrou em evidência a discussão sobre o tema no cenário nacional, sendo mais recentemente criada no governo federal uma comissão interministerial de custos com objetivo de elaborar estudos e propor diretrizes, métodos e procedimentos para subsidiar a implantação de Sistemas de Custos na Administração Pública Federal. Tendo em vistas essas necessidades, o presente trabalho tem por objetivo principal verificar a adequabilidade do Sistema Gerencial de Custos (SISCUSTOS) implantado no Exército Brasileiro permite a apuração de custos sob a ótica da teoria contábil e complementarmente analisar se o sistema de custos adequasse as metodologias do custeio ABC e fornece subsídios para a tomada de decisões. Para isso realizou-se um estudo de caso de natureza qualitativa, coletando-se dados de fontes primárias e secundárias, além de entrevistas com os servidores responsáveis pelo desenvolvimento, implantação e operacionalização do sistema. O resultado verificado foi que as funcionalidades disponibilizadas pelo SISCUSTOS vislumbram a aderência do sistema com o plano teórico, permitindo que as informações extraídas da contabilidade governamental contemporânea sejam ajustadas, para uma possível aproximação da contabilidade orçamentária com a contabilidade patrimonial, necessitando apenas de alguns ajustes para itens aqui denominados como peculiares da contabilidade governamental. No caso do método de custeio ABC observou-se que a metodologia está sendo subtilizada, e que o grau desejado em extrair todas as contribuições disponibilizadas pelo ABC somente virá com a maturidade da gestão de custos, sendo que, para atingir tais objetivos haverá a necessidade de se fixar como atributos cognitivos os 4C - Cultura de Custos, Comprometimento, Competição e Confiabilidade - entre os usuários do sistema e a alta administração.

Variantes no gene MBL2 codificador da Lectina Ligante de Manose (MBL): implicações na leishmaniose visceral humana

A leishmaniose visceral (LV) ou calazar é uma doença endêmica, crônica, grave e de alta letalidade se não tratada. Os estudos apontam a proteína Lectina Ligante de Manose (MBL), codificada pelo gene MBL2, como uma peça-chave na imunidade inata, dada a sua função no reconhecimento microbiano, na eliminação, inflamação e morte celular. Neste trabalho realizamos um estudo do tipo caso-controle que teve como objetivo investigar a associação entre variantes no gene MBL2 e a suscetibilidade à LV em indivíduos residentes em áreas endêmicas da Ilha de São Luís-MA. A amostra foi constituída por 322 indivíduos, sendo 161 casos com LV, não aparentados, de ambos os sexos, residentes em áreas endêmicas da doença na Ilha de São Luís e 161 controles saudáveis, não infectados e não aparentados da mesma região. A identificação dos casos de LV se deu por meio do contato constante com os principais hospitais e ambulatórios de referência para a doença na cidade. Também foram feitas buscas de pacientes com LV em ambiente domiciliar, a partir de registros da FUNASA-MA. A análise molecular consistiu na genotipagem de 6 variantes localizadas na região promotora [posições -550 (C>G), -221(G>C), +4(C>T)] e codificadora [códons 52 (C>T), 54 (G>A) e 57 (G>A)] do gene MBL2, através da reação em cadeia da polimerase e sequenciamento automático. A dosagem da proteína MBL no soro foi realizada pelo teste de ELISA. Verificamos que os fenótipos MBL dependem do conjunto de alelos presentes no gene MBL2, sendo nítido o efeito que as variantes defectivas causam nos níveis da proteína. Não encontramos diferença significativa entre casos e controles em relação à distribuição dos genótipos MBL2 e dos níveis séricos de MBL. As frequências alélicas das variantes exônicas na amostra total mostram que o alelo A é o mais comum (74,8%) e que os alelos defectivos (B, C e D) se encontram principalmente em heterozigose (36,6%), o que reforça a ideia de que alelos MBL2 defectivos são mantidos na população por conferirem vantagem seletiva aos heterozigotos. Em relação aos 3 principais polimorfismos existentes na região promotora, verificamos ser a variante -221G (Y) a mais frequente (88%) seguida de +4C (P) (73%) e de -550C (L) (67%). Identificamos oito haplótipos em MBL2 num total de 644 cromossomos avaliados, em 30 combinações diferentes, sendo HYPA e LYQA os mais frequentes e HYPD e HYPB os mais raros. Todos os portadores de combinações de haplótipos homozigotos para alelos defectivos apresentaram níveis séricos de MBL indetectáveis. Os genótipos LYQA/LYQA e HYPA/HYPA apresentaram as maiores concentrações médias de MBL no soro. A combinação entre SNPs no éxon 1 e na região promotora do gene MBL2 resulta em grande variação nas concentrações de MBL em indivíduos saudáveis. Consideramos que o conjunto de dados gerados é uma contribuição valiosa que poderá ser expandida para outros cenários.

Northerly Distribution of White Sharks, Carcharodon carcharias, in the Eastern Pacific and Relation to ENSO Events

Twenty-nine verified records of white sharks, Carcharodon carcharias, from British Columbia and Alaska waters (1961–2004) are presented. Record locations ranged from lat. 48°48ʹN to lat. 60°17ʹN, including the northernmost occurrence of a white shark and the first report of this species from the central Bering Sea. White sharks recorded from the study area were generally large, with 95% falling between 3.8 and 5.4 m in length. Mature white sharks of both sexes occur in British Columbia and Alaska waters, although they do not necessarily reproduce there. White sharks actively feed in the study area; their diet is similar to that reported for this species from Washington and northern California waters. Sea surface temperature (SST) concurrent with white shark records from the study area ranged from 16°C to between 6.4°C and 5.0°C, extending the lower extreme of the range of SST from which this species has been previously reported. White shark strandings are rarely reported, yet 16 (55%) of the records in this study are of beached animals; strandings generally occurred later in the year and at lower latitudes than nonstrandings. No significant correlation was found between white shark records in the study area and El Niño events and no records occurred during La Niña events. The data presented here indicate that white sharks are more abundant in the cold waters of British Columbia and Alaska than previous records suggest.

浙江嵊州早上新世植物群重建和古气候定量研究

上新世时期是地球环境发展变化过程中由温暖的中新世向冰期-间冰期交替出现的更新世的过渡时期，研究上新世的气候有助于研究现代全球气候变化趋势。我国上新世植物群研究不多，尤其缺乏早上新世植物群的研究。在研究化石植物群的过程中，叶角质层的信息通常被忽视。迄今，我国古气候的定量研究主要集中在山东山旺和云南地区，研究的主要是中新世和晚上新世的古气候，早上新世气候的定量研究国内外都未见报道。 本论文以采自浙江中部嵊州地区硅藻土中的植物叶和果实为材料，通过光学显微镜、荧光显微镜和扫描电镜观察，对提取的化石叶角质层和叶结构进行研究，对比研究现代相关类群植物的叶片，确定了化石植物类群计15科24属（或亚科）34种。同时参照现代植物分布，恢复了早上新世嵊州地区古植被情况，进一步运用共存分析（Co-existence Approch）定量重建了当时的古气候，得到古年均温、古年较差和古年降水量等7个参数。 研究表明，叶结构和叶角质层可以应用于化石植物类群的鉴定。光学显微镜和荧光显微镜下可以获得的信息有：气孔、表皮细胞形状及大小、表皮细胞垂周壁、分泌结构、表皮毛或毛基等。扫描电镜观察的是叶表皮细胞表面的情况，如细胞外壁是否被蜡质以及蜡质的交结情况，气孔外壁是否增厚呈环等。 经化石植物类群鉴定，早上新世（约4Ma）嵊州地区植被属亚热带常绿阔叶林。推测：该地区当时存在一个较大的湖泊，湖泊边缘水中生长有菱角，湖泊周边可能有海拔超过1400m的山地。 常绿阔叶林主要成分是壳斗科植物，其中青冈属植物可能是建群植物。自低海拔到高海拔地区都有分布的是：栎属、栗属、桤木属植物，青杨梅。低海拔地区（<600m）分布的植物有：海南锥，樟。中低海拔地区（300-1000m）分布着：柯属、黄杨属植物，水青冈，海南油丹，江南油杉，福建柏。中高海拔地区（>700m）分布有：高山栎、黄肉楠属植物，米心水青冈，榉树，建始槭，天台鹅耳枥和昌化鹅耳枥。除了上述类群，林中还散布着鼠李属、杜鹃花属和冬青属的植物，豆科崖豆藤属植物则缠绕一些较大乔木生长。另外，在一些土壤、有机质易堆积的洼地生长有竹林，山地贫瘠的地方生长着柏属植物。 嵊州早上新世化石植物群反映的植被同浙江地区现代植被相似。第三纪浙江地区从针叶林或阔叶树为主的针-阔叶混交林过渡到常绿-落叶阔叶林，再发展为常绿阔叶林。 依据23个植物类群分析获得7个古气候参数：年均温17.7-21.4°C，最热月均温22.2-27°C，最冷月均温8.4-13.4°C，年较差12.1-15.3°C，年降水量1136-1869.9mm，最大月降水量211.8-283.3mm，最小月降水量20.3-36.8mm。 对比现代嵊州地区气候参数，早上新世嵊州地区年降水量略高于现代，年均温比现代高1.3-5°C，年较差为12.1-15.3°C。早上新世期嵊州地区四季气温比现代平稳。

Liver genomic responses to ciguatoxin: evidence for activation of Phase I and Phase II detoxification pathways following an acute hypothermic response in mice

Ciguatoxins (CTX) are polyether neurotoxins that target voltage-gated sodium channels and are responsible for ciguatera, the most common fish-borne food poisoning in humans. This study characterizes the global transcriptional response of mouse liver to a symptomatic dose (0.26 ng/g) of the highly potent Pacific ciguatoxin-1 (P-CTX-1). At 1 h post-exposure 2.4% of features on a 44K whole genome array were differentially expressed (p ≤ 0.0001), increasing to 5.2% at 4 h and decreasing to 1.4% by 24 h post-CTX exposure. Data were filtered (|fold change| ≥ 1.5 and p ≤ 0.0001 in at least one time point) and a trend set of 1550 genes were used for further analysis. Early gene expression was likely influenced prominently by an acute 4°C decline in core body temperature by 1 h, which resolved by 8 h following exposure. An initial downregulation of 32 different solute carriers, many involved in sodium transport, was observed. Differential gene expression in pathways involving eicosanoid biosynthesis and cholesterol homeostasis was also noted. Cytochrome P450s (Cyps) were of particular interest due to their role in xenobiotic metabolism. Twenty-seven genes, mostly members of Cyp2 and Cyp4 families, showed significant changes in expression. Many Cyps underwent an initial downregulation at 1 h but were quickly and strongly upregulated at 4 and 24 h post-exposure. In addition to Cyps, increases in several glutathione S-transferases were observed, an indication that both phase I and phase II metabolic reactions are involved in the hepatic response to CTX in mice.

Effect of salt on the level of histamine in preserved fish (Herring, Clupea harengus)

Histamine levels in batches of heavily salted (fish:salt ratio 4:1) herring (Clupea harengus) were monitored during ripening at 4°C and 25°C. The batches studied were prepared from both pre-spawning and post-spawning (spent) fish using new and used salt. Salt levels in the flesh, which reached 11 to 14% (wet weight basis) during the ripening period, were found to retard histamine formation. During normal spoilage of ice chilled fish, histamine levels had been reported to exceed 50mg/100g flesh as it approached the limit of edibility whilst, in the heavily salted fish, levels remained below 20mg/100g flesh throughout the ripening periods of 18 months for the 4°C batches and 3 months for the 25°C batches. This was the case when the samples were set up and the salt allowed penetrating the flesh at 4°C. When, however, the samples were set up and initially stored at ambient (10-15°C) temperature the histamine levels in the flesh rose above 20mg/100g before enough salt had penetrated to inhibit its generation. The gradual rise in levels which, nevertheless, occurred over the ripening periods followed significantly (5% level of significance) different trends, being greater in the batches prepared from pre-spawning than those from spent fish.

低温吸胀对大豆种子呼吸代谢影响的研究

大豆是重要的油料和蛋白植物。在生产实践中，在播种后达到早苗和齐苗是大豆丰收的前提。种子的吸胀冷害是农业生产的严重问题。吸胀冷害发生在种子开始吸水萌动的萌发初始阶段。吸胀冷害不仅发生在高寒地带和低温冷湿地区，尤其在我国东北地区，造成我国乃至全球大豆不同程度的减产。吸胀冷害的原初作用位点在生物膜上，本实验从呼吸代谢的角度研究吸胀冷害对种子活力的影响，探讨吸胀冷害的机制。 本实验选用由黑龙江省黑河农业科学院提供的对低温中度敏感的黑河13 号大豆种子为材料，分别经22°C、10°C 和4°C 恒温培养箱24 h 后，测定其生理指标，通过透射电镜观察细胞超微结构，利用蛋白质组技术研究低温吸胀与种子呼吸代谢的关系，得到的结果如下： 低温吸胀阻碍胚轴膜系统的修复。通过电解质渗漏率测定发现，4°C 到22°C 温度范围内，提高吸胀温度有助于保持细胞膜的完整性，显著降低吸胀后胚轴电解质渗漏。在低温下吸胀，胚轴活性氧清除酶的活性受到抑制，活性氧含量增加，增强了膜脂过氧化作用，进而导致种子活力下降。 通过透射电子显微镜观察，大豆种子在22°C 吸胀24 h 后，胚轴细胞液泡明显变大，在细胞中所占比例很高，并且细胞内膜系统比较发达，能清晰观察到细胞核，线粒体，质膜，内质网整齐有序的形状。胚轴的细胞含有其它结构正常的细胞器，包括细胞壁，胞间连丝，淀粉粒和油体等。线粒体的外膜、内膜、嵴发育较完善。10°C 和4°C 的吸胀严重损伤了胚轴中细胞器的修复，细胞膜不规则，没有发现内质网和胞间连丝，线粒体的体积较小以及膜系统不发达，尤其是4°C 吸胀的胚轴中细胞器的损伤更加严重，细胞膜系统紊乱。 低温吸胀抑制了线粒体从轻线粒体向重线粒体的修复，以及线粒体的耗氧能力。22°C 吸胀的线粒体的总体耗氧能力较高，电子传递主要是利用复合体I 的电子传递途径。10°C 吸胀的线粒体总体耗氧呼吸较低，且其线粒体的电子传递主要以复合体II 的途径。4°C 吸胀的线粒体的耗氧能力则更低。 将分离得到的线粒体进行的蛋白质组分析，共分离400 多个蛋白点，其中有20 个点有表达差异。经ESI-Q-TOF-MS/MS 鉴定，六个下调的蛋白质分别为ATP 合成酶的亚基 (线粒体的氧化磷酸化)，线粒体延长因子Tu（线粒体基因组转录）， 苹果酸脱氢酶（三羧酸循环），精氨酸酶（尿素循环）和2 个线粒体chaperonin-60 （热稳定蛋白）。这些蛋白在低温吸胀时下调表达，影响了线粒体的正常生理代谢，说明它们在维持线粒体正常代谢中起到了重要的作用。 综上所述，低温吸胀影响了线粒体的结构和生理功能的修复，减少了能量和中间物质供应给种子萌发，造成了种子活力的下降。

Short-term preservation of Brachionus calyciflorus: effects of storage on protein, lipid and carbohydrate contents

The short-term preservation of Brachionus calyciflorus for 45 days at three different temperatures (4, -4 and -20°C) led to decrease in protein, lipid and carbohydrate contents in all the three cases. However, the rate of deterioration was much higher at 4C than at -4 and -20°C. At 4C, protein, lipid and carbohydrate contents reduced by 76.78, 81.11 and 62.83%, respectively, and at -4°C, these were 27.94, 37.46 and 18.42%, respectively, whereas at -20°C, the deterioration was limited to 9.28, 16.44 and 11.35%, respectively, when compared with the control values. Thus, preservation at -20°C is comparatively better as it exerts limited effect on the protein, lipid and carbohydrate contents of B. calycijlorus.