976 resultados para hyperpolarisierte Gase, He-3, MRT, Lunge, Applikator


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In this conversation, Kevin K. Kumashiro shares his reflections on challenges to publishing anti-oppressive research in educational journals. He then invites eight current and former editors of leading educational research journals--William F. Pinar, Elizabeth Graue, Carl A. Grant, Maenette K. P. Benham, Ronald H. Heck, James Joseph Scheurich, Allan Luke, and Carmen Luke--to critique and expand on his analysis. Kumashiro begins the conversation by describing his own experiences submitting manuscripts to educational research journals and receiving comments by anonymous reviewers and journal editors. He suggests three ways to rethink the collaborative potential of the peer-review process: as constructive, as multilensed, and as situated. The eight current and former editors of leading educational research journals then critique and expand Kumashiro's analysis. Kumashiro concludes the conversation with additional reflections on barriers and contradictions involved in advancing anti-oppressive educational research in educational journals. (Contains 3 notes.)

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The literature was reviewed and analyzed to determine the feasibility of using a combination of acid hydrolysis and CO2-C release during long-term incubation to determine soil organic carbon (SOC) pool sizes and mean residence times (MRTs). Analysis of 1100 data points showed the SOC remaining after hydrolysis with 6 M HCI ranged from 30 to 80% of the total SOC depending on soil type, depth, texture, and management. Nonhydrolyzable carbon (NHC) in conventional till soils represented 48% of SOC; no-till averaged 56%, forest 55%, and grassland 56%. Carbon dates showed an average of 1200 yr greater MRT for the NHC fraction than total SOC. Longterm incubation, involving measurement of CO2 evolution and curve fitting, measured active and slow pools. Active-pool C comprised 2 to 8% of the SOC with MRTs of days to months; the slow pool comprised 45 to 65% of the SOC and had MRTs of 10 to 80 yr. Comparison of field C-14 and (13) C data with hydrolysis-incubation data showed a high correlation between independent techniques across soil types and experiments. There were large differences in MRTs depending on the length of the experiment. Insertion of hydrolysis-incubation derived estimates of active (C-a), slow (C-s), and resistant Pools (C-r) into the DAYCENT model provided estimates of daily field CO2 evolution rates. These were well correlated with field CO2 measurements. Although not without some interpretation problems, acid hydrolysis-laboratory incubation is useful for determining SOC pools and fluxes especially when used in combination with associated measurements.

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The Space Day has been running at QUT for about a decade. The Space Day started out as a single lecture on the stars delivered to a group of high school students from Brisbane State High School (BSHS), just across the river from QUT and therefore convenient for the school to visit. I was contacted by Victor James of St. Laurence’s College (SLC), Brisbane asking if he could bring a group of boys to QUT for a lecture similar to that delivered to BSHS. However, for SLC a hands-on laboratory session was added to the lecture and thus the Space Day was born. For the Space Day we have concentrated on year 7 – 10 students. Subsequently, many other schools from Brisbane and further afield in Queensland have attended a Space Day.

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Flinders University and Queensland University of Technology, biofuels research interests cover a broad range of activities. Both institutions are seeking to overcome the twin evils of "peak oil" (Hubbert 1949 & 1956) and "global warming" (IPPC 2007, Stern 2006, Alison 2010), through development of Generation 1, 2 and 3 (Gen-1, 2 & 3) biofuels (Clarke 2008, Clarke 2010). This includes development of parallel Chemical Biorefinery, value-added, co-product chemical technologies, which can underpin the commercial viability of the biofuel industry. Whilst there is a focused effort to develop Gen-2 & 3 biofuels, thus avoiding the socially unacceptable use of food based Gen-1 biofuels, it must also be recognized that as yet, no country in the world has produced sustainable Gen-2 & 3 biofuel on a commercial basis. For example, in 2008 the United States used 38 billion litres (3.5% of total fuel use) of Gen-1 biofuel; in 2009/2010 this will be 47.5 billion litres (4.5% of fuel use) and in 2018 this has been estimated to rise to 96 billion litres (9% of total US fuel use). Brazil in 2008 produced 24.5 billion litres of ethanol, representing 37.3% of the world’s ethanol use for fuel and Europe, in 2008, produced 11.7 billion litres of biofuel (primarily as biodiesel). Compare this to Australia’s miserly biofuel production in 2008/2009 of 180 million litres of ethanol and 75 million litres of biodiesel, which is 0.4% of our fuel consumption! (Clarke, Graiver and Habibie 2010) To assist in the development of better biofuels technologies in the Asian developing regions the Australian Government recently awarded the Materials & BioEnergy Group from Flinders University, in partnership with the Queensland University of Technology, an Australian Leadership Award (ALA) Biofuel Fellowship program to train scientists from Indonesia and India about all facets of advanced biofuel technology.

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This guide explains how copyright law applies to Australian government material, how copyright can be managed to facilitate beneficial open access practices by government, how CC licenses can be used to achieve open access to government material, and provides practical step-by-step guidance for agencies and their officers on licensing and use of government copyright materials under CC 3.0 Australia licences.

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Professor Christian Langton is a medical physicist at Queensland University of Technology in Brisbane. He has developed a way of preparing children who are about to have either radiotherapy or MRI imaging procedures and is seeking research partners to develop and test these further. This is a great opportunity for nurses interested in research, and who have access to a children’s hospital, to work with Professor Langton on some truly innovative, multidisciplinary research.

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A 4 week intensive measurement campaign was conducted in March–April 2007 at Agnes Water, a remote coastal site on the east coast of Australia. A Volatility-Hygroscopicity-Tandem Differential Mobility Analyser (VH-TDMA) was used to investigate changes in the hygroscopic properties of ambient particles as volatile components were progressively evaporated. Nine out of 18 VH-TDMA volatility scans detected internally mixed multi-component particles in the nucleation and Aitken modes in clean marine air. Evaporation of a volatile, organic-like component in the VH-TDMA caused significant increases in particle hygroscopicity. In 3 scans the increase in hygroscopicity was so large it was explained by an increase in the absolute volume of water uptake by the particle residuals, and not merely an increase in their relative hygroscopicity. This indicates the presence of organic components that were suppressing the hygroscopic growth of mixed particles on the timescale of humidification in the VH-TDMA (6.5 secs). This observation was supported by ZSR calculations for one scan, which showed that the measured growth factors of mixed particles were up to 18% below those predicted assuming independent water uptake of the individual particle components. The observed suppression of water uptake could be due to a reduced rate of hygroscopic growth caused by the presence of organic films or organic-inorganic interactions in solution droplets that had a negative effect on hygroscopicity.

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The structures of the anhydrous 1:1 proton-transfer compounds of isonipecotamide (4-carbamoylpiperidine) with picric acid and 3,5-dinitrosalicylic acid, namely 4-carbamoylpiperidinium 2,4,6-trinitrophenolate, C6H13N2O8+ C6H2N3O7- (I) and 4-carbamoylpiperidinium 2-carboxy-4,6-dinitrophenolate, C6H13N2O8+ C7H3N2O7-: two forms, the monoclinic alpha-polymorph (II) and the triclinic beta-polymorph (III) have been determined at 200 K. All compounds form hydrogen-bonded structures, one-dimensional in (II), two-dimensional in (I) and three-dimensional in (III). In (I), the cations form centrosymmetric cyclic head-to-tail hydrogen-bonded homodimers [graph set R2/2(14)] through lateral duplex piperidinium N---H...O(amide) interactions. These dimers are extended into a two-dimensional network structure through further interactions with anion phenolate-O and nitro-O acceptors, including a direct symmetric piperidinium N-H...O(phenol),O(nitro) cation--anion association [graph set R2/1(6)]. The monoclinic polymorph (II) has a similar R2/1(6) cation-anion hydrogen-bonding interaction to (I) but with an additional conjoint symmetrical R1/2(4) interaction as well as head-to-tail piperidinium N-H...O(amide) O hydrogen bonds and amide N-H...O(carboxyl) hydrogen bonds, give a network structure which include large R3/4(20) rings. The hydrogen bonding in the triclinic polymorph (III) is markedly different from that of monoclinic (II). The asymmetric unit contains two independent cation-anion pairs which associate through cyclic piperidinium N-H...O,O'(carboxyl) interactions [graph set R2/1(4)]. The cations also show the zig-zag head-to-tail piperidinium N-H...O(amide) hydrogen-bonded chain substructures found in (II) but in addition feature amide N-H...O(nitro) and O(phenolate) and amide N-H...O(nitro) associations. As well there is a centrosymmetric double-amide N-H...O(carboxyl) bridged bis(cation-anion) ring system [graph set R2/4(8)] in the three-dimensional framework. The structures reported here demonstrate the utility of the isonipecotamide cation as a synthon with previously unrecognized potential for structure assembly applications. Furthermore, the structures of the two polymorphic 3,5-dinitrosalicylic acid salts show an unusual dissimilarity in hydrogen-bonding characteristics, considering that both were obtained from identical solvent systems.

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The structures of the anhydrous 1:1 proton-transfer compounds of isonipecotamide (piperidine-4-carboxamide) with the three isomeric mononitro-substituted benzoic acids and 3,5-dinitrobenzoic acid, namely 4-carbamoylpiperidinium 2-nitrobenzoate (I), 4-carbamoylpiperidinium 3-nitrobenzoate (II), 4-carbamoylpiperidinium 4-nitrobenzoate (III), (C6H13N2O+ C7H4NO4-) and 4-carbamoylpiperidinium 3,5-dinitrobenzoate (IV) (C6H13N2O+ C7H5N2O6-)respectively, have been determined at 200 K. All salts form hydrogen-bonded structures: three-dimensional in (I), two-dimensional in (II) and (III) and one-dimensional in (IV). Featured in the hydrogen bonding of three of these [(I), (II) and (IV)] is the cyclic head-to-head amide--amide homodimer motif [graph set R2/2~(8)] through a duplex N---H...O association, the dimer then giving structure extension via either piperidinium or amide H-donors and carboxylate-O and in some examples [(II) and (IV)], nitro-O atom acceptors. In (I), the centrosymmetric amide-amide homodimers are expanded laterally through N-H...O hydrogen bonds via cyclic R2/4(8) interactions forming ribbons which extend along the c cell direction. These ribbons incorporate the 2-nitrobenzoate cations through centrosymmetric cyclic piperidine N-H...O(carboxyl) associations [graph set R4/4(12)], giving inter-connected sheets in the three-dimensional structure. In (II) in which no amide-amide homodimer is present, duplex piperidinium N-H...O(amide) hydrogen-bonding homomolecular associations [graph set R2/2(14)] give centrosymmetric head-to-tail dimers. Structure extension occurs through hydrogen-bonding associations between both the amide H-donors and carboxyl and nitro O-acceptors as well as a three-centre piperidinium N-H...O,O'(carboxyl) cyclic R2/1(4) association giving the two-dimensional network structure. In (III), the centrosymmetric amide-amide dimers are linked through the two carboxyl O-atom acceptors of the anions via bridging piperidinium and amide N-H...O,O'...H-N(amide) hydrogen bonds giving the two-dimensional sheet structure which features centrosymmetric cyclic R4/4(12) associations. In (IV), the amide-amide dimer is also centrosymmetric with the dimers linked to the anions through amide N-H...O(nitro) interactions. The piperidinium groups extend the structure into one-dimensional ribbons via N-H...O(carboxyl) hydrogen bonds. The structures reported here further demonstrate the utility of the isonipecotamide cation in molecular assembly and highlight the efficacy of the cyclic R2/2(8) amide-amide hydrogen-bonding homodimer motif in this process and provide an additional homodimer motif type in the head-to-tail R2/2(14) association.

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Numerous difficulties are associated with the conduct of preclinical studies related to skin and wound repair. Use of small animal models such as rodents is not optimal because of their physiological differences to human skin and mode of wound healing. Although pigs have previously been used because of their human-like mode of healing, the expense and logistics related to their use also renders them suboptimal. In view of this, alternatives are urgently required to advance the field. The experiments reported herein were aimed at developing and validating a simple, reproducible, three-dimensional ex vivo de-epidermised dermis human skin equivalent wound model for the preclinical evaluation of novel wound therapies. Having established that the human skin equivalent wound model does in fact “heal," we tested the effect of two novel wound healing therapies. We also examined the utility of the model for studies exploring the mechanisms underpinning these therapies. Taken together the data demonstrate that these new models will have wide-spread application for the generation of fundamental new information on wound healing processes and also hold potential in facilitating preclinical optimization of dosage, duration of therapies, and treatment strategies prior to clinical trials.