116,073 research outputs found
Mangroves and aquaculture in Southeast Asia.
No full textThe history of brackishwater pond culture in the Philippines and elsewhere in Southeast Asia has been associated with mangrove loss because in earlier times, the larger society has viewed mangroves and other wetlands as wastelands to be developed. In a proactive move to address environmental concerns over shrimp aquaculture, the SEAFDEC Council in 1999 mandated the development of environment-friendly shrimp culture and the build-up of expertise in mangroves.
This paper reviews the status of mangroves and their conversion to culture ponds in Southeast Asia, and the environmental impacts of aquaculture, aside from habitat loss. To improve the sustainability of brackishwater aquaculture, recommendations include an inventory of mangrove and pond culture areas in the region, zonation of mangrove areas within the context of integrated coastal zone management, aqua-silviculture and environmentfriendly aquaculture, rehabilitation of degraded mangroves, and enforcement of existing laws including the buffer zone/mangrove greenbelt requirement
Primavera remisión de V. equinoccio de la primavera.
No full text[ES] Definición del término Primavera remisión de V. equinoccio de la primavera. en el diccionario Dicter.[EN] Definition of the word Primavera remisión de V. equinoccio de la primavera. in the dictionary Dicter
A PROPAGAÇÃO DA DEMOCRACIA NA PRIMAVERA ÁRABE: A INFLUÊNCIA DOS FATORES INTERNACIONAIS NA DIFUSÃO DA DEMOCRATIZAÇÃO NA TÚNISIA, NO EGITO E NA LÍBIA
No full textTCC (graduação) - Universidade Federal de Santa Catarina. Centro Sócio-Econômico. Relações Internacionais.A Primavera Árabe teve início em dezembro de 2010 na Tunísia e em um rápido período de tempo se espalhou pela região do norte da África e do Oriente Médio. Esta pesquisa busca entender como um evento isolado se tornou uma série de eventos, analisando a contribuição dos fatores internacionais na proliferação da democracia. Esta pesquisa examina Tunísia, Egito e Líbia e estuda cinco fatores internacionais de difusão da democracia: impacto da vizinhança, clima político regional, incentivos externos, prevalência das condições conjunturais e atores e eventos externos. Tenta-se identificar os fatores internacionais que contribuíram para o início e a disseminação do processo conhecido como Primavera Árabe, na Tunísia, Egito e Líbia. Ao final, conclui-se pela relevância dos fatores internacionais como estopim para a proliferação das revoltas nos três países estudados. Os fatores externos foram fundamentais para propagar a revolta e a democracia pela regiã
A review of maturation and reproduction in closed thelycum penaeids
No full textCommercially important penaeids of the closed thelycum group belong to five subgenera of the genus Penaeus — Penaeus, Fenneropenaeus, Marsupenaeus and Melicertus that are almost exclusively Indo-West Pacific and Farfantepenaeus that is predominantly Western Atlantic. Since the ablation of Penaeus duorarum more than a decade ago, the first for any penaeid, around 23 species have been matured in captivity, 17 of them belonging to the closed thelycum subgenera (P. aztecus, P. brasiliensis, P. californiensis, P. duorarum, P. esculentus, P. indicus, P. japonicus, P. kerathurus, P. latisulcatus, P. merguiensis, P. monodon, P. notialis, P. orientalis, P. paulensis, P. penicillatus, P. plebejus, and P. semisulcatus).
The complete spectrum of controlled reproduction in penaeids covers maturation, spawning, hatching of eggs into viable larvae, and the production of postlarvae to constitute the next batch of broodstock. The full closing of the cycle has been achieved in at least six closed thelycum species whereas gaps, e.g. inability of mature females to spawn or nonhatching of eggs, remain for the others.
Spawners or mature females used in commercial hatcheries and research laboratories are either wild-caught or matured in captivity with human control ranging from nil to a regular closing of the cycle. Wild spawners may be spawned directly after capture and transport or subjected to environmental manipulation, e.g. thermal control to induce or inhibit spawning. Females matured in captivity may come from wild broodstock (adults and subadults caught from estuaries or "sourced" by trawlers from offshore waters) or captive (pond- or tank-reared) broodstock. Introduced or exotic penaeid species must depend on a pond- or tank-reared broodstock whereas indigenous prawns and shrimps may be constituted from wild or captive broodstock.
There are three basic approaches employed singly or in combination to induce ovarian maturation in penaeids — endocrine, dietary or nutritional and environmental. Endocrine manipulation has so far been synonymous with unilateral eyestalk ablation, a technique with far-reaching impact on penaeid aquaculture. Closed thelycum penaeids may be classified into those that require ablation in order to mature and those that do not. To a third group belong species that have been experimentally induced to mature with and without ablation.
Diets for maturation include fresh and frozen animal sources (mussel, clam, oyster, squid, marine worms, shrimps, fish) and formulated pellets given in any combination. The choice of marine worms and mollusks is based on their high levels of arachidonic, eicosapentaenoic and docosahexaenoic acid, the dominant fatty acids found in mature ovaries and testes. Environmental parameters studied in relation to maturation include light (intensity, quality and photoperiod), temperature, salinity and pH.
Although a regular closing of the cycle has been achieved for some, the state-of-the-art for most penaeids is the successful production of larvae and postlarvae from either wild spawners or wild immature/spent females matured/rematured in captivity. The improvement of reproductive performance including larval quality from captive broodstock remains a major area for future research and includes the determination of minimum age and size for maturation. The complete description of the nutritional and environmental requirements for maturation should lead to the development of alternatives to ablation such as photoperiod manipulation or the use of reproductive hormones.
The present focus on characterizing the physicochemical and dietary requirements for maturation should be extended to other phases of reproduction: mating, spawning, fertilization and hatching. Studies on biology (molting, mating, fertilization including the cortical reaction) and biochemistry (maturation stages) provide baseline information for designing maturation tanks and formulating broodstock pellets. Investigations of wild stocks complement laboratory studies in elucidating the interrelationships among molting, mating, maturation and spawning.
Manual spermatophore transfer is being developed to solve the problem of nonmating in closed (and open) thelycum species. This technique will also be useful in future hybridization work, together with in vitro fertilization
Reunión Primavera 2013: Entrevista a Noemí V. Mendoza Díaz
No full textLa Dra. Noemí Mendoza nos comenta los asuntos que trata la Comunidad Enseñanza de la Ingeniería, los principales objetivos y la situación actual de la comunidad en México.Entrevista realizada a la Dra. Noemí V. Mendoza Díaz Coordinadora de la Comunidad Enseñanza de la Ingeniería durante la Reunión CUDI, Primavera 2013.Entrevista_Noemi_Mendoza.wm
INTERNET E DEMOCRACIA: Implicações na Organização Política de Tunísia e Egito a partir da Primavera Árabe
No full textTCC (graduação) - Universidade Federal de Santa Catarina. Centro Sócio-Econômico. Relações Internacionais.A Primavera Árabe, que iniciou em janeiro de 2011 na Tunísia e se espalhou pelo Norte da África e pelo Oriente Médio, foi marcada por ser um movimento que reivindicou, em alguns casos de forma bem sucedida, a democracia em estados que há anos eram se caracterizavam por seus governos autoritários e repressão. Porém, um elemento que marcou este fenômeno ainda mais em seu início, foi o uso da internet para a articulação de protestos e veiculação de informações. Ideias sobre a internet ser vista como ferramenta política voltaram à tona. Esta pesquisa analisa o papel da internet no processo de transição democrática em dois países pioneiros da Primavera Árabe, Tunísia e Egito. Através de uma pesquisa qualitativa que utilizou as teorias democráticas de Rousseau e Dahl; assim como àquelas referentes ao contemporâneo conceito de democracia digital; um histórico do desenvolvimento da internet, a análise de elementos que podem interferir na oscilação do nível de divisão digital como: liberdade na internet, número de usuários da internet, a demografia dos países, o nível de desemprego, os níveis de alfabetização e as taxas de inscrições escolares; e uma correlação destes fatores com a crise da democracia, este trabalho sugere estratégias governamentais gerais para se aumentar a qualidade da democracia por meio do uso da internet e outras específicas às características de Tunísia e Egito, respectivamente
Simplified model for an alpha2-omega dynamo fed by dynamical evolution of the zonal shear
No full textA facility for the measurement of electron transport parameters in a gas mixture.
No full textA facility for studying electron transport parameters in a given gas mixture is illustrated. A controlled ionization is induced by means of multiple-photon processes by focussing a short (similar to 1 ns) pulsed nitrogen laser in the gas gap. The test gas volume, where a suitable E-field is applied, is installed on a micrometric motion system which allows to accurately scan the volume (resolution similar to 3 mum) with a beam focus waist of the order of 10 mum. Such a facility has been used for measurements of the gas parameters of the He drift chamber of KLOE experiment at DA phi NE and for preliminary measurements of gain and attachment coefficients in the binary mixtures (C2H2F4 + 3%, 10% isoC(4)H(10)) planned for the ATLAS and CMS RPC systems. An upgraded version of the set-up, which allows also for O-2 and H2O vapour controlled contamination, is currently being used for measurements on ternary mixtures (C2H2F4 + isoC(4)H(10) + SF6)
Trattamento degli strabismi consecutivi a decompressione orbitaria per oftalmopatia distiroidea: nostre esperienze.
No full text- …
