962 resultados para Ku Klux Klan (1915- )
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ChiritaDidymocarpus14075Wood20 23C. longicalyx J. M. Li & Y. Z. WangC. prostrata J. M. Li & Y. Z. Wang 2 DNAITStrnL-FChirita sect. GibbosaccusChirita sect. Chirita DNAITStrnL-F ; Didymocarpus s. str.Didymocarpus sect. ElatiD. citrinusDidymocarpus sect. DidymocarpusGyrocheilos
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EXTRACT (SEE PDF FOR FULL ABSTRACT): We have analyzed streamflow variations recorded at 15 USGS gauging stations in California during the past 90 years or so. The anomalies (departures from the 1960-1990 mean discharge) of streamflow on annual-to-decadal time scales are strongly correlated with precipitation anomalies in each drainage basin. ... Although causes of the decadal climate (precipitation) variability are not known with certainty, the use of streamflow records may help us understand the relative strengths of moisture sources and shift of the jet stream in atmospheric circulation.
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The collection of blue green algae kept at the herbarium of the Royal Botanical Gardens, Peradeniya, was collected by Ferguson more than 70 years ago. Since then many changes have taken place in the taxonomy of the blue green algae. West (1902), Lemmermann (1907), Wine (1915), Crow (1923), Bharadwaja (1934) and Holsinger (1935) had described some of the blue green algae of Ceylon. While examining the collections of blue green algae kept at the herbarium, the authors found that most of the identifications were incorrect and required revision. In the present paper 20 blue green algae are described. The classification and key to the species are based on the characters given by Desikachary (1959). Blue green algae are important to fisheries since Chanos larvae feed on them.
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The Crown-of-Thorns starfish Acanthaster planci is a predator of coral and has been responsible for the widespread destruction of coral reefs. In Sri Lanka this starfish was first reported by Clarke in 1915. Recently skin-divers reported that Acanthaster planci was present in very large numbers in the coastal waters off Trincomalee, especially on the coral formations around Pigeon Island. It is well known that the multiplication of the starfish to plague proportions is a serious threat to the coral reef formations round the Island. If it were allowed to continue its depredations the entire coral reef belt round the Island might be destroyed in a short time. The monsoon waves would then convert the dead coral to rubble. In the absence of a barrier against the advancing waves during the monsoon it would also lead to serious erosion of the shoreline. The coral reef fish would also disappear with the destruction of the coral formations. On account of these considerations it was decided to conduct a survey of the Crown-of-Thorns starfish in eastern coastal waters in order to estimate the magnitude of the population of the starfish in these waters.
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Si bien existen varios ensayos biogrficos que enfocan diferentes momentos de su vida (ANNIMO, 1963, BAHAMONDE, 1962, LPEZ et al., 2015, NION, 2015, PEQUEO, 2015, SNCHEZ CARRILLO, 2001), hasta donde tenemos conocimiento, no se ha publicado an una bibliografa completa de la obra del Dr. FERNANDO DE BUEN Y LOZANO (Fig. de tapa). Bibliografas parciales se encuentran, entre otros, en los autores arriba citados. Aqu nos atrevemos a hacer el intento, aunque en forma defectuosa, ya que muchas de sus publicaciones no las hemos podido consultar directamente (se sealan con un asterisco, *). En parte nos hemos basado en una compilacin hecha por el propio DE BUEN, que abarca los aos 1915 a 1949 (Fig. 1), aunque no siempre con los datos necesarios para una completa informacin sobre la publicacin; en lo posible intentamos complementarla. En sus casi cincuenta aos de actividad cientfica, lleg a producir casi 300 ttulos, de variado contenido, aunque siempre relacionados con el medio acutico, sea marino o dulceacucola. Esta produccin se puede dividir en cuatro perodos, que comienza con su etapa espaola, europea y africana (marroqu), entre 1915 y 1937, durante la cual public ms de 140 ttulos. Como consecuencia de la Guerra Civil Espaola, en 1939 se radica en Mxico, donde permanece desde el 12 de Julio de 1939 hasta Noviembre 1946, pas al que regresa entre 1953 y 1957. Durante este perodo escribe unos 70 artculos. Entre esas dos etapas mexicanas, estuvo brevemente radicado en el Uruguay, desde el 26 de Noviembre de 1946 hasta 1953, sin duda la etapa de menor produccin cientfica, con una docena trabajos. A sta sigue el ltimo perodo de su vida, en Chile (Fig. 2), la que lamentablemente termina trgicamente, en 1962. Durante este perodo publica ms de 60 publicaciones, de los cuales, aparentemente, seis quedan inditas. Cabe sealar que durante estas tres etapas de exilio americano, si bien sus publicaciones estn mayoritariamente relacionadas con el pas de residencia, hay algunas excepciones. Preivo a estas estadas en Amrica, hay que mencionar tres europeas, fuera de Espaa, a saber: en el Museo Oceanogrfico de Mnaco (1919), en el Instituto Centrale di Biologia Marina, Messina, Italia (1919), y en el Laboratorio Arago, Banyuls sur Mer, Francia (1939). En general, puede considerarse que FERNANDO DE BUEN fue un investigador solitario, ya que solamente seis, de sus casi 300 trabajos, fueron publicados en colaboracin: dos con su hermano SAD DE BUEN (#31 y 32), dos con F. FRADE (#115 y 116), y dos con MANUEL ZOZAYA (#162 y 176). En su obra cientfica hemos podido identificar la descripcin original de 12 gneros, 9 subgneros, 54 especies y 11 subespecies, como se indican en la Tabla I.
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Accumulating evidence suggests that unicellular Archezoa are the most primitive eukaryotes and their nuclei are of significance to the study of evolution of the eukaryotic nucleus. Nuclear matrix is an ubiquitous important structure of eukaryotic nucleus; its evolution is certainly one of the most important parts of the evolution of nucleus. To study the evolution of nuclear matrix, nuclear matrices of Archezoa are investigated. Giardia lamblia cells are extracted sequentially. Both embedment-free section EM and whole mount cell EM of the extracted cells show that, like higher eukaryotes, this species has a residual nuclear matrix in its nucleus and rich intermediate filaments in its cytoplasm, and the two networks connect with each other to form a united network. But its nuclear matrix does not have nucleolar matrix and its lamina is not as typical as that of higher eukaryotes; Western blotting shows that lamina of Giardia and two other Archezoa Entamoeba invadens and Trichomonas vaginali all contain only one polypeptide each which reacts with a mammalia anti-lamin polyclonal serum and is similar to lamin B (67 ku) of mammlia in molecular weight. According to the results and references, it is suggested that nuclear matrix is an early acquisition of the eukaryotic nucleus, and it and the "eukaryotic chromatin" as a whole must have originated very early in the process of evolution of eukaryotic cell, and their origin should be an important prerequisite of the origin of eukaryotic nucleus; in the iamin (gene) family, B-type lamins (gene) should be the ancestral type and that A-type lamins (gene) might derive therefrom.
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Invertebrates constitute a major link in energy flow culminating into fish production in aquatic ecosystems. In tropical water bodies relatively little research has been done on invertebrate ecology especially their role in fishery production. European scientists through periodic expeditions to Africa in the last quarter of the 20th century carried out the earliest research on zooplankton. Rzoska (1957) listed these early workers including Stuhlmann (1888), Weltner (1897) and Mrazek (1897-1898). Daday (1907), Verestchagin (1915) and Delachaux (1917) undertook further work during the early twentieth century. These earlyworks provide a useful basis for tracking community changes by comparison with modem investigations. Worthington (1931) provided the first quantitative account of the zooplankton of Lake Victoria along with information on diurnal vertical migrations, compared to a temperate lake. The establishment of the East African Freshwater Fisheries Research Organisation (EAFFRO) at Jinja in 1947 enabled investigations on the fisheries, algae, invertebrates and water quality aspects of the lake (EAFFRO Annual Reports 1947-1977) to be regularly carried out. Macdonald (1956) made the first detailed observations on the biology of chaoborids and chironomids (IakefJies) in relation to the feeding of the elephant snout fish, Mormyrus kannume. A detailed study of the biology of the mayfly, Povilla adusta Navas with special reference to the diurnal rhythms of activity was carried out by Hartland-Rowe (1957). The search to unravel the ecological role of aquatic invertebrates in the production dynamics of the lake has taken invertebrate research to greater heights through recent investigations including Okedi (1990), Mavut
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1987, (Trichuride Railliet, 1915), , T. rhinopithecus sp. nov. 111 9
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A(Anguilla anguilla,)(Ig),,(Aeromonas hydrophila)Ig(Ig+):IgSDS-PAGE68 ku26 ku2,Ig151 200Ig+,,
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<> ()1915,100,5060,1,000,
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We explore the intrafamilial relationships of East Asian bagrid catfishes (Hemibagrus, Pseudobagrus, Pelteobagrus, and Leiocassis) based on 245 sequences of 1092 bp mitochondrial cytochrome b fragments. Four haplotypes were found to be shared by Pseudobagrus ussuriensis, Pelteobagrus vachelli and Pelteobagrus nitidus. Phylogenetic trees were performed using the neighbor joining, maximum parsimony, maximum likelihood, and Bayesian likelihood methods. The phylogenetic trees based on NJ, MP, ML and BL inferences strongly support polyphyleticism for the currently recognized genera Pseudobagrus, Pelteobagrus and Leiocassis. However, the species currently assigned to these three genera form a robustly monophyletic group with relatively low genetic divergence. The structure of maxillary barbels and serrations on the anterior edge of the pectoral spines seem to be indicatory of appropriate phylogenetic traits. We propose that only Hemibagrus and Pseudobagrus are the only valid genera of East Asian bagrids.
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Background: Some triploid and tetraploid clones have been identified in the gynogenetic gibel carp, Carassius auratus gibelio Bloch, by karyotypic and cytologic analyses over many years. Further, 5-20% males and karyotypic diversity have been found among their natural and artificial populations. However, the DNA contents and the relation to their ploidy level and chromosome numbers have not been ascertained, and whether normal meiosis occurs in spermatogenesis needs to be determined in the different clones. Methods: The sampled blood cells or sperms were mixed with blood cells from chicken or individual gibel carp and fixed in 70% pre-cooled ethanol overnight at 4degreesC. The mixed cell pellets were washed 2-3 times in 1x phosphate buffered saline and then resuspended in the solution containing 0.5% pepsin and 0.1 M HCl. DNA was stained with propidium iodide solution (40 mug/mL) containing 4 kU/ml RNase. The measurements of DNA contents were performed with Phoenix Flow Systems. Results: Triploid clones A, E, F, and P had almost equal DNA content, but triploid clone D had greater DNA content than did the other four triploid clones. DNA content of clone M (7.01 +/- 0.15 pg/nucleus) was almost equal to the DNA content of clone D (5-38 +/- 0.06 pg/nucleus) plus the DNA content of common carp sperm (1.64 +/- 0.02 pg/nucleus). The DNA contents of sperms from clones A, P, and D were half of their blood cells, suggesting that normal meiosis occurs in spermatogenesis. Conclusions: Flow cytometry is a powerful method to analyze genetic heterogeneity and ploidy level among different gynogenetic clones of polyploid gibel carp. Through this study, four questions have been answered. (a) The DNA content correlation among the five triploid clones and one multiple tetraploid clone was revealed in the gibel carp, and the contents increased with not only the ploidy level but also the chromosome number. (b) Mean DNA content was 0.052 pg in six extra chromosomes of clone D, which was higher than that of each chromosome in clones A, E, F, and P (about 0.032 pg/ chromosome). This means that the six extra chromosomes are larger chromosomes. (c) Normal meiosis occurred during spermatogenesis of the gibel carp, because DNA contents of the sperms from clones A, P, and D were almost half of that in their blood cells. (d) Multiple tetraploid clone M (7.01 +/- 0.15 pg/nucleus) contained the complete genome of clone D (5.38 +/- 0.06 pg/nucleus) and the genome of common carp sperm (1.64 +/- 0.02 pg/nucleus). Cytometry Part A 56A:46-52, 2003. (C) 2003 Wiley-Liss, Inc.