948 resultados para Perry, Chris


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Parthenium hysterophorus L., (Asteraceae) commonly known as parthenium weed, is a highly invasive plant that has become a problematic weed of pasture lands in Australia and many other countries around the world. For the management of this weed, an integrated approach comprising biological control and plant competition strategies was tested in southern central Queensland. Two competitive pasture plant species (butterfly pea and buffel grass), selected for their high competitive ability, worked successfully with the biological control agent (Epiblema strenuana Walker) to synergistically reduce the biomass of parthenium weed, by between 62 and 69%. In the presence of biological control agent, the corresponding biomass of competitive plants, butterfly pea and buffel grass increased in comparison to when the biological control agent had been excluded, by 15 and 35%, respectively. This suggests that biological control and competitive plants can complement one another to bring about improved management of parthenium weed in Australia. Further, this approach may be adopted in countries where some of the biological control agents are already present including South Africa, Ethiopia, India, Pakistan and Nepal.

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Private press aluminum phonographic record sent to Jakob Plaut in Berlin by his sons Günther and Walter in Maine, United States, on his 58th birthday with their birthday wishes and an interview. Each side is only a few minutes long.

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Creative Work as part of the Nocturne series

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On beef cattle feed pen surfaces, fresh and decayed manure is mixed with base rock or soil (base). Quantifying this mixing has beneficial applications for aspects including nutrient and greenhouse gas budgeting. However, no practical methods exist to quantify mixing. We investigated if measuring element concentrations in: (A) fresh manure, (B) base material, and (C) pen manure offers a promising method to quantify manure/base mixing on pen surfaces. Using three operational beef feedlots as study sites, we targeted carbon (C), and silicon (Si), which are the two most abundant and easily measurable organic and inorganic elements. Our results revealed that C concentrations were strongly (>15 times) and significantly (P < 0.05) higher whereas Si concentrations strongly (>10 times) and significantly (P < 0.01) lower in fresh manure than base material at all three sites. These relative concentrations were not significantly impacted by manure decay, as determined by an 18-week incubation experiment. This suggested that both of these elements are suitable markers for quantifying base/manure mixing on pens. However, due to the chemical change of manure during decay, C was shown to be an imprecise marker of base/manure mixing. By contrast, using Si to estimate base/manure mixing was largely unaffected by manure decay. These findings were confirmed by measuring C and Si concentrations in stockpiled pen surface manure from one of the sites. Using Si concentrations is a promising approach to quantify base/manure mixing on feed pens given that this element is abundantly concentrated in soils and rocks.

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Productivity decline in sown grass pastures is widespread in northern Australia and reduces production by approximately 50%, a farm gate cost to industry of > $17B over the next 30 years. Buffel grass is the most widely established sown species (>75% of plantings) and has been estimated to be “dominant” on 5.8 M hectares and “common” on a further 25.9 M hectares of Queensland. Legumes are the most cost effective mitigation option and can reclaim 30-50% of lost production. Commercial use of legumes has achieved mixed results with notable successes but many failures. There is significant opportunity to improve commercial results from legumes using existing technologies, however there is a need for targeted research to improve the reliability of establishment and productivity of legumes. This review recommends the grazing industry invest in targeted R,D&E to assist industry in improving production and sustainability of rundown pastures.

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The Brigalow Belt bioregion of southern and central Queensland supports a large percentage of northern Australia's sown pastures and beef herd. The Brigalow soils were widely thought to have adequate phosphorus (P) for cropping, sown pastures and grazing animals, which has led to almost no use of P fertiliser on sown pastures. The majority of pastures established in the region were sown with tropical grasses only (i.e. no legumes were sown). Under grass-only pastures, nitrogen (N) mineralisation rates decline with time since establishment as N is 'tied-up' in soil organic matter. This process leads to a significant decline in pasture and animal productivity and is commonly called 'pasture rundown'. Incorporating pasture legumes has been identified as the best long-term solution to improve the productivity of rundown sown grass pastures. Pasture legumes require adequate P to grow well and fix large amounts of N to increase the productivity of rundown sown grass pastures. Producers and farm advisors have traditionally thought that P fertiliser is not cost-effective for legume-based improved pastures growing on inland areas of Queensland despite there being little, if any, data on production responses or their economic outcomes. Recent studies show large and increasing areas of low plant available soil P and large responses by pasture legumes to P fertiliser on Brigalow soils. The economic analysis in this scoping study indicates potential returns of 9–15% on extra funds invested from the application of P fertiliser, when establishing legumes into grass pastures on low P soils (i.e. lower than the critical P requirement of the legume grown). Higher returns of 12–24% may be possible when adding P fertiliser to already established grass/legume pastures on such soils. As these results suggest potential for significant returns from applying P fertiliser on legume pastures, it is recommended that research be conducted to better quantify the impacts of P fertiliser on productivity and profit. Research priorities include: quantifying the animal production and economic impact of fertilising legume-based pastures in the sub-tropics for currently used legumes; quantifying the comparative P requirements and responses of available legume varieties; understanding clay soil responses to applied P fertiliser; testing the P status of herds grazing in the Brigalow Belt; and quantifying the extent of other nutrient deficiencies (e.g. sulphur and potassium) for legume based pastures. Development and extension activities are required to demonstrate the commercial impacts of applying P fertiliser to legume based pastures.

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Clays could underpin a viable agricultural greenhouse gas (GHG) abatement technology given their affinity for nitrogen and carbon compounds. We provide the first investigation into the efficacy of clays to decrease agricultural nitrogen GHG emissions (i.e., N2O and NH3). Via laboratory experiments using an automated closed-vessel analysis system, we tested the capacity of two clays (vermiculite and bentonite) to decrease N2O and NH3 emissions and organic carbon losses from livestock manures (beef, pig, poultry, and egg layer) incorporated into an agricultural soil. Clay addition levels varied, with a maximum of 1:1 to manure (dry weight). Cumulative gas emissions were modeled using the biological logistic function, with 15 of 16 treatments successfully fitted (P < 0.05) by this model. When assessing all of the manures together, NH3 emissions were lower (×2) at the highest clay addition level compared with no clay addition, but this difference was not significant (P = 0.17). Nitrous oxide emissions were significantly lower (×3; P < 0.05) at the highest clay addition level compared with no clay addition. When assessing manures individually, we observed generally decreasing trends in NH3 and N2O emissions with increasing clay addition, albeit with widely varying statistical significance between manure types. Most of the treatments also showed strong evidence of increased C retention with increasing clay additions, with up to 10 times more carbon retained in treatments containing clay compared with treatments containing no clay. This preliminary assessment of the efficacy of clays to mitigate agricultural GHG emissions indicates strong promise.

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Land-applied manures produce nitrous oxide (N2O), a greenhouse gas (GHG). Land application can also result in ammonia (NH3) volatilisation, leading to indirect N2O emissions. Here, we summarise a glasshouse investigation into the potential for vermiculite, a clay with a high cation exchange capacity, to decrease N2O emissions from livestock manures (beef, pig, broiler, layer), as well as urea, applied to soils. Our hypothesis is that clays adsorb ammonium, thereby suppressing NH3 volatilisation and slowing N2O emission processes. We previously demonstrated the ability of clays to decrease emissions at the laboratory scale. In this glasshouse work, manure and urea application rates varied between 50 and 150 kg nitrogen (N)/ha. Clay : manure ratios ranged from 1 : 10 to 1 : 1 (dry weight basis). In the 1-year trial, the above-mentioned N sources were incorporated with vermiculite in 1 L pots containing Sodosol and Ferrosol growing a model pasture (Pennisetum clandestinum or kikuyu grass). Gas emissions were measured periodically by placing the pots in gas-tight bags connected to real-time continuous gas analysers. The vermiculite achieved significant (P ≤ 0.05) and substantial decreases in N2O emissions across all N sources (70% on average). We are currently testing the technology at the field scale; which is showing promising emission decreases (~50%) as well as increases (~20%) in dry matter yields. This technology clearly has merit as an effective GHG mitigation strategy, with potential associated agronomic benefits, although it needs to be verified by a cost–benefit analysis.

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- Objective To evaluate dietary intake impact outcomes up to 3.5 years after the NOURISH early feeding intervention (concealed allocation, assessor masked RCT). - Methods 698 first-time mothers with healthy term infants were allocated to receive anticipatory guidance on protective feeding practices or usual care. Outcomes were assessed at 2, 3.7 and 5 years (3.5 years post-intervention). Dietary intake was assessed by 24-hour recall and Child Dietary Questionnaire. Mothers completed a food preference questionnaire and Children’s Eating Behaviour Questionnaire. Linear mixed models assessed group, time and time x group effects. - Results There were no group or time x group effects for fruit, vegetables, discretionary food and non-milk sweetened beverages intake. Intervention children showed a higher preference for fruits (74.6% vs 69.0% liked, P<.001), higher Child Dietary Questionnaire score for fruit and vegetables (15.3 vs 14.5, target>18, P=0.03), lower food responsiveness (2.3 vs 2.4, of maximum 5, P=.04) and higher satiety responsiveness (3.1 vs 3.0, of maximum 5, P=.04). - Conclusions Compared to usual care, an early feeding intervention providing anticipatory guidance regarding positive feeding practices led to small improvements in child dietary score, food preferences and eating behaviours up to 5 years of age, but not in dietary intake measured by 24-hour recall.

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Tutkielmassa tarkastellaan ekofeminismiä ja sen tarjoamia mahdollisuuksia uskonnollisten luontodiskurssien tutkimiselle. Ekofeminismi on saavuttanut Suomessa yllättävän vähäistä kiinnostusta siitäkin huolimatta, että sekä feministisellä tutkimuksella että toisaalta uskontoekologialla on jalansijansa suomalaisessakin uskontotieteessä. Tutkielman tehtävänä onkin osaltaan paikata tätä tyhjiötä ja paitsi esitellä keskeisiä ekofeministisiä teorioita, niin myös näiden pohjalta kehitellä uudenlaista näkökulmaa uskontotieteelliseen, ihmisen ja luonnon suhdetta koskevaan tutkimukseen. Metodologisena viitekehyksenä tutkielmassa on käytetty sekä van Dijkin kriittisen diskurssianalyysin että Chris Weedonin kuvaileman jälkistrukturalistisen teorian perusperiaatteita, vaikkei diskurssianalyysi olekaan tutkielman pääasiallinen tavoite. Vaikka tutkielmassa sitoudutaan avoimesti ekofeministiseen projektiin, on näkökulma myös käytettyyn tutkimuskirjallisuuteen kriittinen: yhtäältä ekofeminististä näkökulmaa esitetään vaihtoehdoksi ns. perinteisille uskonnontutkimuksen teorioille, toisaalta tarkastellaan itseään ekofeminismiä ja sen lähtökohtia itsekriittisesti. Tutkielmassa käytetty uskonnon määritelmä nojaa Clifford Geerzin määritelmään uskonnosta symbolijärjestelmänä, joka osaltaan muokkaa yhteiskunnallista järjestystä sekä yhteiskunnan jäsenten syvimpiä arvoja ja asenteita. Näin nähtynä uskonnolla on tärkeä asema myös luontodiskurssien muodostamisessa ja ylläpitämisessä, eikä sitä näin ollen ole syytä jättää ekofeministisen tarkastelun ulkopuolelle. Ekofeminismi on 1970-luvulla syntynyt feminismin haara, jonka perustana on ajatus, että kaikki alistamisen muodot ovat verkkomaisessa suhteessa toisiinsa ja niiden taustalla toimivat samat mekanismit, oli kyseessä sitten rotuun, luokkaan, sukupuoleen tai lajiin perustuva sortaminen. Sorron taustalla toimivan ideologian ydin on käsitys järjen vallasta luonnon yli, jolloin alistetut ryhmät sekä naisellistetaan että naturalisoidaan. Tämän käsityksen perustan muodostavat länsimaista ajattelua jäsentävät dualismit kuten järki/tunne, mies/nainen, mieli/ruumis, yhteiskunta/luonto. Myös ympäristökriisin katsotaan nousevan näistä dualismeista, joten niiden tarkastelu, esiinkaivaminen ja purkaminen ovat yksi tärkeä osa ekofeminististä projektia. Näin ollen myös tässä tutkielmassa on kiinnitetty erityishuomio dualismeihin käyttäen apuna Val Plumwoodin teoriaa dualistisista mekanismeista ja toisaalta Karen Warrenin teoriaa dualismeihin nojaavasta herruuden logiikasta. Tutkielmassa luodaan myös katsaus länsimaisen, dualismeille pohjaavan luontosuhteen syntyyn niin filosofiassa, tieteessä kuin kristinuskossakin siten, kuin se ekofeminismin parissa yleisesti käsitetään. Tutkielmassa keskitytään kahteen ekofeministiseen pääsuuntaukseen, materiaaliseen ja kulttuuriseen ekofeminismiin. Näistä ensimmäisen taustalla ovat erilaiset sosialistiset ja marxilaiset teoriat: painotus on biologisesti ja sosiaalisesti sukupuolittuneessa työn jakautumisessa sekä naisen asemassa uusintavan työn tekijänä ja välittäjänä kulttuurin ja luonnon välissä. Kulttuurinen ekofeminismi puolestaan näkee ongelmien juuret enempi kulttuurisina, jolloin pääpaino on patriarkaalisen kulttuurin tavassa väheksyä kaikkea feminiiniseksi luokiteltua ja siten sekä naisia että luontoa. Tutkielmassa nämä kaksi näkökulmaa yhdistetään, sillä symbolis-materiaalisen sortokäsityksen mukaisesti huomio tulee kiinnittää yhtä lailla sorron materiaaliseen kuin kulttuuriseenkin puoleen. Tämän yhdistämisen tuloksena muodostuu uudenlainen näkökulma: ekofeministinen holismi. Ekofeministisen holismin teorian juuret ovat paitsi yllä mainituissa ekofeminismin muodoissa, niin myös pyrkimyksessä ylittää ekofeministisen ajattelun sisäiset dualismit. Teoria nojaa yhtäältä ns. ekologiseen hoivaetiikkaan ja toisaalta ajatukseen ekologisesta holismista: kokonaisuus hahmotetaan osiensa kautta, ja pääpaino on erilaisten suhteiden verkkomaisessa ymmärtämisessä. Huomio kiinnitetään yhtä lailla materiaaliseen kuin diskursiiviseenkin todellisuuteen, sillä valtarakenteet muotoutuvat näiden kahden vuorovaikutuksesta. Ekofeministinen holismi tarjoaakin uskonnollisten luontodiskurssien kriittiseen tarkasteluun monipuolisen näkökulman, jonka avulla on mahdollista paljastaa näiden diskurssien taustalla vaikuttavia dualistisia rakenteita samalla, kun huomioidaan myös näiden rakenteiden materiaaliset ja sosiaaliset vaikutukset. Kasaantuvien ekologisten ja sosiaalisten ongelmien edessä tällainen näkökulma puoltaa paikkaansa myös uskontotieteessä. Avainsanat: ekofeministiset teoriat - länsimainen luontosuhde - dualismit - ekologinen holismi - ekologinen hoivaetiikka - uskonnollinen luontodiskurssi

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3D Computer Graphics (CG) has become the dominant medium for modern animated feature films. It is widely understood that traditional principles of animation developed in the 1930s at the Walt Disney Studio remain applicable to this new medium and heavily influence the range of aesthetic motion styles in contemporary animation. Via a frame-by-frame textual analysis of four animated feature films, this thesis tests and confirms the validity of the principles of animation and expands upon them by reinterpreting the Disney principle of appeal as aesthetic harmony, which delineates the way in which character posing and transitions between poses contribute to the animated motion styles that animators work in today.

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The effect of foreign aid on the welfare levels of both the recipient and the donor country has been a much analysed topic for research in both the theory of international trade and development economics. In the development economics literature, concerns have been raised since the 1960s on the possible adverse effect of foreign aid on domestic savings and growth.1 The trade theory literature in this respect is much older and dates back to the 1920s when Professors Keynes and Ohlin debated on the effect of foreign aid on international terms of trade.2 Ever since, the terms of trade effect has been the cornerstone in the analysis of the welfare effect of foreign aid in the trade theory literature.3 After some early confusion, it is now well established that in a Walrasian stable world economy with two countries, a necessary condition for foreign aid to have perverse effects is that there is some distortion in either of the two countries.4 It is also known that, under normality and substitutability of goods, untied aid cannot be strictly Pareto-improving in a tariff distorted world.5

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Silicon particles standing proud on aluminium-silicon alloy surfaces provide protection in tribology. Permanent sinking of such particles into the matrix under load can be deleterious. The mechanical response of the alloy to nano-indentation of single silicon particles embedded in the matrix is explored. A nominal critical pressure required to plastically deform the matrix to permanently embed the particle is determined experimentally. Within a framework suggested by two-dimensional models of plastic response to indentation, a probable correlation is established between the normal mean pressure required to cause permanent sinking of silicon particles and a factor which relates the relevant particle dimensions.