526 resultados para Preston
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In the 1970s, acid sulfate soils (ASS) distributed within about 720 ha of predominantly mangrove and salt pan wetlands at East Trinity in north Queensland were developed after the area was isolated from tidal flooding by a surrounding seawall and the installation of tidal gates on major drainage creeks. Following drainage and oxidation of these estuarine acidic sediments, resultant acid leachate caused considerable, ongoing environmental problems including regular fish kills. A rehabilitation program covering much of these former tidal wetlands commenced in 2000 using a lime-assisted tidal exchange management regime. Changes in the established populations of estuarine fish and crustaceans were monitored in the two creeks (Firewood and Hills Creeks) where tidal flows were reinstated. In Firewood Creek between 2001 and 2005, there was a progressive increase in fish species richness, diversity and abundance. The penaeid prawn Fenneropenaeus merguiensis was a major component of the cast net catches in the lower sections of both Firewood and Hills Creeks but its relative abundance decreased upstream of the tidal gates on the seawall. Well established stocks of predominantly juvenile, male Scylla serrata resident upstream of the tidal gates indicated suitable habitats with acceptable water and sediment quality and adequate availability of food. The regular fish kills that occurred prior to the management regime abated and, overall, the implementation of the rehabilitation program is yielding positive benefits for the local fisheries.
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This article provides a summary of research undertaken during a seven-year study from 1995-2002 which focussed on prawn farm ecosystems, their ecological impacts, and cost-effective effluent treatment systems.
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Direct contact mechanism in bioleaching implies prior mineral adhesion of Acidithiobacillus ferrooxidans and subsequent enzymatic attack.Prior bacterial adaptation to sulfide mineral substrates influences bacterial ferrous ion oxidation rates. It is highly beneficial to understand major biooxidation mechanisms with reference to solution- and mineral-grown cells in order to optimize bioleaching reactions. For A. ferrooxidans grown in the presence of solid substrates such as sulfur, pyrite and chalcopyrite, bacterial adhesion is required for its enzymatic machinery to come into close contact for mineral dissolution.But when grown in solution substrate such as ferrous ions and thiosulfate, such an adhesion machinery is not required for substrate utilization. Proteinaceous compounds were observed on the surface of sulfur-grown cells. Such an induction of relatively hydrophobic proteins and down regulation of exposed polysaccharides leads to changes in cell surface chemistry. Sulfur-grown and pyrite- and chalcopyrite-grown bacterial cells were found to be more efficient in the bioleaching of chalcopyrite than those grown in the presence of ferrous ions and thiosulfate. (C) 2010 Elsevier B.V. All rights reserved.
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The mechanism of sub-microscopic precipitation in an Al-Zn-Mg alloy selected for its maximum response to ageing has been studied by a standardized oxide-replica technique in a 100 kV. Philips Electron Microscope. Contrary to earlier conclusions, examination of the oxide replicas has been shown to reveal details of the precipitation process almost as clearly as the thin-foil transmission technique. The reported formation of spherical Guinier-Preston zones followed by the development of a Widmanstaetten pattern of precipitated platelets has been confirmed. The zones have, however, been shown to grow into the platelets and not to dissolve in the matrix as reported earlier. The precipitation process has been correlated with the Hardness/Ageing Time curve and the structure of the precipitates has also been discussed.
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Tässä tutkielmassa tutkin tanssin liikemateriaalin kirjoittamista suomalaisessa tanssitaiteessa. Tutkielman tarkoitus on pohtia 1) mikä tanssista taiteenlajina tekee sellaisen, että virallinen notaatio on katsottu tarpeettomaksi, 2) mitä keinoja Suomessa tanssin parissa työskentelevät ovat kehittäneet selviytyäkseen ilman yhteistä notaatiota, sekä 3) miten yhteisen tanssinotaation laajempi käyttö voisi mahdollisesti hyödyttää tanssia. Tutkielman näkökulma on poikkitaiteellinen: vertaan tanssia ja sen käsittämistä taiteena sen sisartaiteeseen, musiikkiin. Tärkeimmät käsitellyt teoreetikot ovat musiikkipsykologi John A. Sloboda, symbolista representaatiota käsitelleet Marc Leman ja Kari Kurkela sekä musiikin ruumiillisuutta tutkinut musiikkitieteilijä Suzanne Cusick. Tanssin tutkimuksen piiristä ammennan teoreettista materiaalia ennen kaikkea Rudolf Labanin ja Valerie Preston-Dunlopin liikkeen analyysista sekä tanssinotaatiota käsitelleiden Claudia Jeschken, Judy Van Zilen, Victoria Wattsin ja Grahm McFeen artikkeleista. Toista tutkimuskysymystä varten keräsin v.2009 kyselyaineiston, jota käytän tukemaan teoreettisia väitteitäni notaation käytöstä. Aineiston keruumetodini oli kyselykaavake, joka lähetettiin jokaiseen Suomen tanssioppilaitokseen ja tanssiteattereihin sekä niille ammattimaisesti toimivien tanssiryhmien tanssijoille ja koreografeille ja itsenäisille toimijoille, joiden yhteystiedot olivat saatavilla Tanssin tiedotuskeskuksen tai Tanssin aluekeskusten kautta. Pienen vastausprosentin vuoksi aineistoa ei ollut mielekästä tutkia kvantitatiivisin menetelmin, vaan vastauksia käsitellään havainnollistavina esimerkkeinä tanssin kentältä. Yleisesti suomalaisen tanssitaiteen kentällä yhteisellä notaatiosysteemillä käsitetään labanotaatiota. Notaatio koetaan varsinaisen tanssin päälle liimattuna asiana, ei taiteenlajin ytimeen kuuluvana tekstinä. Suzan Cusackin ruumiillisuusteoriaa mukaillen huomioin, että musiikki on totuttu käsittämään mielen aktiviteettina, kun taas tanssi on nähty lähes täysin ruumiillisena toimintana. Tätä mielen ja kehon vastakkainasettelua vasten notaatiota on perinteisesti sovellettu musiikkiin, mutta tanssiin ei. Kaikki kyselyyn vastanneet suomalaisen tanssitaiteen ammattilaiset kuitenkin kirjoittivat tanssia muistiin paperille. Kerätty materiaali osoitti siihen suuntaan, että symbolinen representaatio tanssista on tärkeä silloin, kun halutaan kuvata tanssin rakennetta: esimerkiksi teoksen muotoa ja dramaturgiaa. Liikemuistin tukena sen rooli korostuu erityisesti opetustyössä. Niin John A. Sloboda kuin Kari Kurkelakin korostavat symbolisen representaation roolia kommunikaation välineenä; lisäksi sen käyttö voi Graham McFeen mukaan selventää teosidentiteettiä sekä luoda arkistoa paitsi valmiista teoksista, myös koreografisesta prosessista ja esitystavoista. Myös nämä molemmat näkökulmat tulivat esiin aineistossa. Toisin kuin musiikin piirissä, notaatiota ei yleensä opeteta tanssijoille. John A. Slobodaa mukaillen esitän, että minkä tahansa notaation osaaminen saattaa muuttaa tanssin tekijän kognitiivisia prosesseja ja ajattelutapaa tanssista, ja suullisesta kulttuurista kirjoitettuun kulttuuriin siirtyminen pitää sisällään niin etuja kuin riskejäkin. Jos notaation siitä huolimatta halutaan tulevan eläväksi osaksi tanssia ja hyödyntävän sitä taiteenlajina, olisi notaatiokysymykseen otettava uudenlainen pedagoginen lähestymistapa: tanssinotaatiota olisi opetettava alkeistasolta lähtien ja kyseenalaistettava ajatus, jonka mukaan koreologi tai notaattori on erillinen ammatti.
Resumo:
Thiobacillus ferrooxidans cells grown on sulfur, pyrite, and chalcopyrite exhibit greater hydrophobicity than ferrous ion-grown cells. The isoelectric points of sulfur-, pyrite-, and chalcopyrite-grown cells were observed to be at a pH higher than that for ferrous ion-grown cells. Microbe-mineral interactions result in change in the surface chemistry of the organism as well as that of the minerals with which it has interacted. Sulfur, pyrite, and chalcopyrite after interaction with T. ferrooxidans exhibited a significant shift in their isoelectric points from the initial values exhibited by uninteracted minerals. With antibodies raised against sulfur-grown T. ferrooxidans, pyrite- and chalcopyrite-grown cells showed immunoreactivity, whereas ferrous ion-grown cells failed to do so. Fourier transform infrared spectroscopy of sulfur-grown cells suggested that a proteinaceous new cell surface appendage synthesized in mineral-grown cells brings about adhesion to the solid mineral substrates. Such an appendage was found to be absent in ferrous ion-grown cells as it is not required during growth in liquid substrates.
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The EC Water Framework Directive (WFD) introduces the concept of the ecological status of surface waters. The WFD requires that water bodies within an ecoregion are divided into waterbody "types" or "ecotypes". The waterbody type is determined by physico-chemical descriptors. A group of representatives from two government environmental agencies (Environment and Heritage Service and the Industrial Research and Technology Unit) and the two universities (Queen's University Belfast and the University of Ulster) in Northern Ireland, has been established to develop methods for measuring the ecological status of lakes, for the purposes of the WFD. The work here is that contributing to the first objective classification into waterbody types.
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Comparison between Galton equation and preston normal logarithms models allowed an empirical reconstitution of probits tables.
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The stock of salmon in any river is largely dependent upon the escapement of sufficient fish to ensure that an adequate quantity of ova is deposited and full use is made of all suitable spawning areas. At the present time, no accurate information is available on the numbers of fish entering rivers. Therefore, catch returns provide valuable information on fish stocks. This report summarises the catch returns for salmon in the Lancashire River Authority in the North of England for the years 1960-1964. Rivers included are the Lune, Ribble, Kent, Leven and Duddon.
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As part of the River Lune juvenile salmonid investigation, a number of sites on the River Wenning catchment were electrofished annually from 1981 - 1985. Particularly low Salmon parr populations were evident for much of the Wenning catchment which has caused some concern. All the Wenning catchment electrofishing results are reported in this paper and comparisons are made with designated groups of sites on the remainder of the Lune catchment. These groups of sites are: River Lune and tributaries, upstream Tebay, Upper Middle Lune, Lower Middle Lune, Lower Lune, Birk & Borrow Becks, Chapel & Crosdale Becks, Rawthey system, Barbon & Leek Becks and the Greta system. The general scarcity of Salmonids in large sections of the main river Wenning probably reflects the apparent limited natural spawning areas on the catchment. Details of Salmon fry and ova planting on the Wenning catchment since 1981 have been collated and whilst survival through the 0+ stage appears to be quite good, recruitment to the 1++ stage appears to be poor. Water quality does not appear to be responsible for the very low salmonid densities at some main river sites but is possibly a factor in apparently preventing any Salmon run in Keasden Beck. Recommendations for future Fisheries and Biological work are given.
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In February 1996 A Strategy for the Management of Salmon in England and Wales was launched by the National Rivers Authority. The strategy concentrates on four main objectives for the management of salmon fisheries in England and Wales: (i) Optimise the number of salmon returning to home water fisheries, (ii) Maintain and improve the fitness and diversity of salmon stocks, (iii) Optimise the total economic value of surplus stocks, (iv) Ensure necessary costs are met by beneficiaries. These four objectives will be addressed through local Salmon Action Plans (SAPs) which will be produced for each of the principle salmon rivers in England and Wales by the year 2001. This Salmon Action Plan for the River Lune reviews the status of the stock and the fisheries, seeks to identify the main factors limiting performance, to draw up and cost a list of options to address these, and to consult with local interest groups.