Triploidy induction in Heterobranchus longifilis (Family: Clariidae) by cold shock

Triploid was induced in African Catfish (Heterobranchus longifilis) by cold shocking activated eggs at 5 degree C for forty minutes starting 3-4 minutes after fertilization. Triploidy was confirmed from mitotic chromosomes prepared from embryo which showed 100% triploidy in the cold shocking treatment and 100% diploidy in the control treatment

Effects of some environmental factors on the fecundity of Tilapia species (Family Cichlidae) in Kigera Reservoir, New Bussa

The effects of some environmental factors on the fecundity of Tilapia species (Family Cichilidae) was carried out at the Kigera dam. Four Tilapia species caught were Tilapia zilli, Hemichromis fasciatus, Sarotherodon galilaeus and Oreochromis niloticus while the environmental factors considered were water temperature, Dissolved Oxygen, pH value, level of rainfall and rate of sunshine and range of time. 43 fish comprising of 25 male with (58.1%) and 18 females having (41.9%) were studied with 74.42% been sexually matured. Both high levels of rainfall and dissolved oxygen favoured fecundity. The spawning peak occurred in (July), environmental factors monitored indicated that dissolved oxygen ranges from 3.7 to 4.45mg/lit rainfall ranges from (34.90mm to 237.80mm) sunshine ranges from (5hrs-8hrs) and pH ranges from (7.35-7.45). The spawning of these species in their natural or hatchery condition is therefore best achieved during the peak of raining season

Expression of eph-family receptor tyrosine kinases and ephrins in the tadpole of the frog Xenopus laevis, and possible roles in the development of retinotectal topography

Assembling a nervous system requires exquisite specificity in the construction of neuronal connectivity. One method by which such specificity is implemented is the presence of chemical cues within the tissues, differentiating one region from another, and the presence of receptors for those cues on the surface of neurons and their axons that are navigating within this cellular environment.

Connections from one part of the nervous system to another often take the form of a topographic mapping. One widely studied model system that involves such a mapping is the vertebrate retinotectal projection-the set of connections between the eye and the optic tectum of the midbrain, which is the primary visual center in non-mammals and is homologous to the superior colliculus in mammals. In this projection the two-dimensional surface of the retina is mapped smoothly onto the two-dimensional surface of the tectum, such that light from neighboring points in visual space excites neighboring cells in the brain. This mapping is implemented at least in part via differential chemical cues in different regions of the tectum.

The Eph family of receptor tyrosine kinases and their cell-surface ligands, the ephrins, have been implicated in a wide variety of processes, generally involving cellular movement in response to extracellular cues. In particular, they possess expression patterns-i.e., complementary gradients of receptor in retina and ligand in tectum- and in vitro and in vivo activities and phenotypes-i.e., repulsive guidance of axons and defective mapping in mutants, respectively-consistent with the long-sought retinotectal chemical mapping cues.

The tadpole of Xenopus laevis, the South African clawed frog, is advantageous for in vivo retinotectal studies because of its transparency and manipulability. However, neither the expression patterns nor the retinotectal roles of these proteins have been well characterized in this system. We report here comprehensive descriptions in swimming stage tadpoles of the messenger RNA expression patterns of eleven known Xenopus Eph and ephrin genes, including xephrin-A3, which is novel, and xEphB2, whose expression pattern has not previously been published in detail. We also report the results of in vivo protein injection perturbation studies on Xenopus retinotectal topography, which were negative, and of in vitro axonal guidance assays, which suggest a previously unrecognized attractive activity of ephrins at low concentrations on retinal ganglion cell axons. This raises the possibility that these axons find their correct targets in part by seeking out a preferred concentration of ligands appropriate to their individual receptor expression levels, rather than by being repelled to greater or lesser degrees by the ephrins but attracted by some as-yet-unknown cue(s).

Structure of the limbs and its significance for the ecology and systematics of the family Chydoridae. [Translation of: Voprosy Gidrobiologii, p385, 1965]

For an explanation of the dynamics of numbers of chydorids, appearing a massive group in the littoral of fresh water bodies, the structure of the limbs of 29 species was studied.

Key to the larvae of the genera of the sub-family Orthocladiinae from Larvae and Pupae of midges of the sub-family Orthocladiinae of the fauna of the USSR. [Translation from: Larvae and pupae of midges of the subfamily Orthocladiinae of the fauna of the USSR (Diptera, Chironomidae = Tendipedidae) (ed. Pankratova V.Ya.), 51-55. Leningrad, Nauka, 1970. ]

A key to the larvae of the genera of the sub-family Orthocladiinae from Larvae and Pupae of midges of the sub-family Orthocladiinae. Parts of the key refer to the rest of the publication which is not included in this partial translation.

Family: Cladophora Kutzing 1843. identification key. [ Translation from: Flora Slodkowodna Polski 10, 227-263, 1972.]

A description of the algal genus Cladophora from Vol 10 of the ”Freshwater Flora of Poland”. Illustrations are included.

The family of chironomids or midges - Chironomidae. Keys to larvae and pupae [Translation from: Guide to the freshwater invertebrates of the European area of the USSR (Plankton and benthos) (ed. L. A. Kutikova and Ya. I. Starobogatov), p.371-431. Leningrad, Gidrometeoizdat, 1977]

The translation of this section of the larger publication ”Opredelitel' presnovodnykh bespozvonochnykh evropeiskoi chasti SSSR. (Plankton i bentos)” provides identification keys to the larvae and pupae of chironomids that occur in the Soviet Union. The morphology of the larvae of Chironomidae is described in the introductory part.

I. Studies on alkaline phosphatase activity in developing sea urchin embryos. II. Studies on the activation of protein biosynthesis in sea urchin eggs at fertilization

I. Alkaline phosphatase activity in the developing sea urchin Lytechinus pictus has been investigated with respect to intensity at various stages, ionic requirements and intracellular localization. The activity per embryo remains the same in the unfertilized egg, fertilized egg and cleavage stages. At a time just prior to gastrulation (about 10 hours after fertilization) the activity per embryo begins to rise and increases after 300 times over the activity in the cleavage stages during the next 60 hours.

The optimum ionic strength for enzymatic activity shows a wide peak at 0.6 to 1.0. Calcium and magnesium show an additional optimum at a concentration in the range of 0.02 to 0.07 molar. EDTA at concentrations of 0.0001 molar and higher shows a definite inhibition of activity.

The intracellular localization of alkaline phosphatase in homogenates of 72-hour embryos has been studied employing the differential centrifugation method. The major portion of the total activity in these homogenates was found in mitochondrial and microsomal fractions with less than 5% in the nuclear fraction and less than 2% in the final supernatant. The activity could be released from all fractions by treatment with sodium deoxycholate.

II. The activation of protein biosynthesis at fertilization in eggs of the sea urchins Lytechinus pictus and Strongylocentrotus purpuratus has been studied in both intact eggs and cell-free homogenates. It is shown that homogenates from both unfertilized and fertilized eggs are dependent on potassium and magnesium ions for optimum amino acid incorporation activity and in the case of the latter the concentration range is quite narrow. Though the optimum magnesium concentrations appear to differ slightly in homogenates of unfertilized and fertilized eggs, in no case was it observed that unfertilized egg homogenates were stimulated to incorporate at a level comparable to that of the fertilized eggs.

An activation of amino acid incorporation into protein has also been shown to occur in parthenogenetically activated non-nucleate sea urchin egg fragments or homogenates thereof. This activation resembles that in the fertilized whole egg or fragment both in amount and pattern of activation. Furthermore, it is shown that polyribosomes form in these non-nucleate fragments upon artificial activation. These findings are discussed along with possible mechanisms for activation of the system at fertilization.

Sentimental education: a study of George Eliots Daniel Deronda

A dissertação analisa Daniel Deronda, de George Eliot, identificando o conceito de maleabilidade como idéia chave para o entendimento dos ideais morais do romance. Discussão do papel desempenhado pelo conceito de maleabilidade no processo de transição da infância para a idade adulta e na apreensão especifica da amizade apresentados no romance

Diasporization and family relations in Nella Larsens Quicksand and Jamaica Kincaids Lucy: the construction of female identity

O principal objetivo desta dissertação é investigar e analisar como os movimentos diaspóricos e as relações familiares exercem influência na construção das identidades das mulheres em Quicksand, de Nella Larsen, e Lucy, de Jamaica Kincaid. As questões a que pretendo responder são: Como as personagens principais, Helga Crane e Lucy, lidam com as diferentes culturas que encontram nas suas trajetórias ? ; Como essas diferentes culturas lidam com essas mesmas personagens?; e Como o encontro entre essas diferentes culturas e as relações familiares são descritos e influenciam na construção da identidade feminina nessas obras?. Minha hipótese é que encontraremos nas obras selecionadas duas jornadas, portadoras tanto de aspectos comuns quanto distintos, que começam com o desejo das personagens principais de escapar da opressão patriarcal. Isto é, Helga Crane e Lucy passam por um período de muitas descobertas sobre elas mesmas e as sociedades com que têm que lidar, o que determina dois produtos diferentes: a construção das identidades híbridas de Lucy, em meio a sua solidão, na obra de Kincaid, e a construção e o sufocamento das identidades de Helga pela religião, o patriarcado e as relações familiares, na obra de Larsen

Synthesis and stereochemical assignments of diastereomeric Ni(II) complexes of glycine Schiff base with (R)-2-(N-{2-[N-alkyl-N-(1-phenylethyl)-amino]acetyl}amino) benzophenone; a case of configurationally stable stereogenic nitrogen

A family of chiral ligands derived from alpha-phenylethylamine and 2-aminobenzophenone were prepared by alkylation of the nitrogen atom. Upon reaction with glycine and a Ni(II) salt, these ligands were transformed into diastereomeric complexes, as a result of the configurational stability of the stereogenic nitrogen atom. Different diastereomeric ratios were observed depending on the substituent R introduced in the starting ligand, and stereochemical assignments were based on X-ray analysis, along with NMR studies and optical rotation measurements.

Matematika eta Artea: Cosmología acrobática - Daniel Tamayo

[EUS] Haur Hezkuntzan beharrezkoa da ikasketa prozesuari zentzua ematea, bereziki abstraktuagoak diren edukiei. Historian zehar izan duten loturagatik aproposa gerta daiteke matematika arte munduarekin eta arte munduko hainbat kontzeptuekin lotzea. Lotura honetaz baliatuz, ikasleek, sentimenduak, sormena eta nozio estetikoak landuko dituzte matematikako, bereziki geometriako edukiak barneratzen dituzten bitartean. Azaltzen den proiektua, 5 urteko gelan gauzatu da, hurbiletik-urrunera kontzeptua praktikan jarriz, ohiko objektuetatik hasi eta Tamayoren“Cosmología acrobática” obran bukatuz, 3 dimentsiotik, 2 dimentsiora.

Direitos humanos, gênero e sexualidade no Estado Constitucional de Direito

Este trabalho tem o objetivo de explorar e investigar o papel desempenhado pelo gênero e pela sexualidade (mais especificamente a orientação sexual e sua aptidão para gerar arranjos íntimos, conjugais e familiares), na formulação de demandas a serem enfrentadas pelo sistema jurídico por meio de novas configurações ou de interpretações dos direitos humanos e fundamentais, possibilitando uma penetração do espaço público por elementos próprios da esfera da intimidade. Isto ocorre por meio de interferências recíprocas balizadas pela gramática constitucional dos direitos humanos e fundamentais, pelas quais se redimensiona a sua formulação e aplicação pelos atores sociais, ao mesmo tempo em que estes invocam sua linguagem inclusiva e igualitária na busca de reconhecimento, inclusão e participação, objetivos que realizam a ideia de reciprocidade contida no Estado de Direito formal, a igualdade de gênero e de orientação sexual torna-se mais do que um ideal regulatório, indo além para tornar-se uma concepção de justiça ela própria, informada também por uma dimensão substantiva de Estado de Direito relacionada ao paradigma democrático, ainda que os direitos que realizam tal ideal de justiça devam ser concretizados judicialmente em diferentes graus, a partir das funções dos direitos e com vistas a compatibilizar universalidade e singularidade e permitindo os canais de comunicação para a veiculação das pretensões da minoria à luz do diálogo com a maioria.