998 resultados para Structural sustainability


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Objective 1. Measure spatial and temporal trawl frequency of scallop grounds using VMS data. This will provide a relative measure of how often individual undersized scallops are caught and put through a tumbler 2. Estimate discard mortality and growth rates for saucer scallops using cage experiments. 3. Evaluate the current management measures, in particular the seasonal closure, rotational closure and seasonally varying minimum legal sizes using stock assessment and management modeling models. Recommend optimal range of management measures to ensure long-term viability and value of the Scallop fishery based on a formal management strategy evaluation. Outcomes acheived to date: 1. Improved understanding of the survival rates of discarded sub-legal scallops; 2. Preliminary von Bertalanffy growth parameters using data from tagged-and-released scallops; 3. Changing trends in vessels and fishing gear used in the Queensland scallop fishery and their effect on scallop catch rates over time using standardised catch rates quantified; 4. Increases in fishing power of vessels operating in the Queensland scallop fishery quantified; 5. Trawl intensity mapped and quantified for all Scallop Replenishment Areas; 6. Harvest Strategy Evaluations completed.

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Roundwood structures have always been used for temporary and low cost shelters and other fleeting structures. Novel concepts for the use of plantation hardwoods in roundwood form in construction were developed and circulated along with an electronic questionnaire to stakeholders representing growers, designers and users of hardwood. Responses indicate that there is a high level of interest in developing products from the emerging small roundwood resource and a detailed program of research was supported and recommended by the majority of participants in the survey. These results indicate a high level of support for further investigation into the use of plantation hardwood for roundwood components. Respondents representing a wide range of stakeholders have indicated that to gain benefit from a detailed project they would require solutions for connection systems and protection from pests and weathering, indications of cost and assurance of ongoing supply for niche applications, data for strength, acoustic dampening and thermal insulation properties, acceptance by regulatory authorities and training for on-site construction.

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This study provides information about wood quality, structural properties, processing characterists and product suitability of wood harvested from fast-grown hardwood plantations. Wood quality attributes tested included density, extractive content, unit shrinkage, heartwood proportion and sapwood width. Structural properties tested included small clear and full section strength and stiffness, hardness, joint group, visual grade assessment and natural vibration-based grade assessment. The variation between the inner, intermediate and outer heartwood zones and the variation between provenances was also tested. Overall, the wood qualtiy attributes measured for 19 year-old E. cloeziana and 15 year-old E. pellita plantation material fall between those expected from the wood of mature, native forest trees and those found in younger plantation material of the same species.

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Oxyphenbutazone, C19H20N203, a metabolite and perhaps the active form of phenylbutazone, is a widely used non-narcotic analgesic and anti-inflammatory pyrazolidinedione derivative. The monohydrate of the compound crystallizes in the triclinic space group Pi with two molecules in a unit cell of dimensions a -- 9.491 (4), b = 10.261 (5), c = 11.036 (3)A and ¢~ = 72.2 (1), fl = 64.3 (1), 7 = 73.0 (1) °. The structure was solved by direct methods and refined to an R value of 0.107 for 1498 observed reflections. The butyl group in the molecule is disordered. The hydroxyl group occupies two sites with unequal occupancies. On account of the asymmetry at the two N atoms and one of the C atoms in the central five-membered ring, the molecule can exist in eight isomeric states, of which four are sterically unfavourable. The disorder in the position of the hydroxyl group can be readily explained on the basis of the existence, with unequal abundances, of all four sterically favourable isomers.The bond lengths and angles in the molecule are similar to those in phenylbutazone. The crystal structure is stabilized by van der Waals interactions, and O-H... O hydrogen bonds involving the carbonyl and the hydroxyl groups as well as a water molecule.

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Understanding the polymerization mechanism of a precursor is indispensable to enhance the requisite material properties. In situ mass spectroscopy and X-ray photoelectron spectroscopy is used in this study to understand the RF plasma polymerization of γ-terpinene. High-resolution mass spectra positive ion mass spectrometry data of the plasma phase demonstrates the presence of oligomeric species of the type [M+H]+ and [2M+H]+, where M represents a unit of the starting material. In addition, there is abundant fragmented species, with most dominant being [M+] (136 m/z), C10H13+ (133 m/z), C9H11+ (119 m/z), and C7H9+ (93 m/z). The results reported in this manuscript enables to comprehend the relationship between the degree of incorporation of oxygen and the rate of deposition with the input RF power.

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Owing to the structural flexibility, uncomplicated processing and manufacturing capabilities, plasma polymers are the subject of active academic as well as industrial research. Polymer thin films prepared from non-synthetic monomers combine desirable optical and physical properties with biocompatibility and environmental sustainability. However, the ultimate expediency and implementation of such materials will dependent on the stability of these properties under varied environmental conditions. Polyterpenol thin films were manufactured at different deposition powers. Under ambient conditions, the bulk of ageing occurred within first 150h after deposition and was attributed to oxidation and volumetric relaxation. Films observed for further 12 months showed no significant changes in thickness or refractive index. Thermal degradation behaviour indicated thermal stability increased for the films manufactured at higher RF powers. Annealing the films to 405°C resulted in full degradation, with retention between 0.29 and 0.99%, indicating films' potential as sacrificial material.

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Tetrapeptide sequences of the type Z-Pro-Y-X were obtained from the crystal structure data on 34 globular proteins, and used in an analysis of the positional preferences of the individual amino acid residues in the β-turn conformation. The effect of fixing proline as the second position residue in the tetrapeptide sequence was studied by comparing the data obtained on the positional preferences with the corresponding data obtained by Chou and Fasman using the Z-R-Y-X sequence, where no particular residue was fixed in any of the four positions. While, in general, several amino acid residues having relatively very high or very low preferences for specific positions were found to be common to both the Z-Pro-Y-X and Z-R-Y-X sequences, many significant differences were found between the two sets of data, which are to be attributed to specific interactions arising from the presence of the proline residue.

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The ultramicrostructure of phases with n = 1, 2 and 3 in the hypothetical series Bi2WnO3n+3 has been investigated by high resolution electron microscopy and energy dispersive X-ray emission spectroscopy. For n = 1 and 2, well ordered phases with the predicted compositions have been obtained, but for n = 3, a severely disordered assemblage containing intergrowths of the two known structures and strips of the n = 3 member is produced. No evidence for ordered structures with n > 2 has yet been obtained.

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The objectives of this study were to investigate the stand structure and succession dynamics in Scots pine (Pinus sylvestris L.) stands on pristine peatlands and in Scots pine and Norway spruce (Picea abies (L.) Karst.) dominated stands on drained peatlands. Furthermore, my focus was on characterising how the inherent and environmental factors and the intermediate thinnings modify the stand structure and succession. For pristine peatlands, the study was based on inventorial stand data, while for drained peatlands, longitudinal data from repeatedly measured stands were utilised. The studied sites covered the most common peatland site types in Finland. They were classified into two categories according to the ecohydrological properties related to microsite variation and nutrient levels within sites. Tree DBH and age distributions in relation to climate and site type were used to study the stand dynamics on pristine sites. On drained sites, the Weibull function was used to parameterise the DBH distributions and mixed linear models were constructed to characterise the impacts of different ecological factors on stand dynamics. On pristine peatlands, both climate and the ecohydrology of the site proved to be crucial factors determining the stand structure and its dynamics. Irrespective of the vegetation succession, enhanced site productivity and increased stand stocking they significantly affected the stand dynamics also on drained sites. On the most stocked sites on pristine peatlands the inter-tree competition seemed to also be a significant factor modifying stand dynamics. Tree age and size diversity increased with stand age, but levelled out in the long term. After drainage, the stand structural unevenness increased due to the regeneration and/or ingrowth of the trees. This increase was more pronounced on sparsely forested composite sites than on more fully stocked genuine forested sites in Scots pine stands, which further undergo the formation of birch and spruce undergrowth beneath the overstory as succession proceeds. At 20-30 years after drainage the structural heterogeneity started to decrease, indicating increased inter-tree competition, which increased the mortality of suppressed trees within stand. Peatland stands are more dynamic than anticipated and are generally not characterized by a balanced, self-perpetuating structure. On pristine sites, various successional pathways are possible, whereas on drained sites the succession has more uniform trend. Typically, stand succession proceeds without any distinct developmental stages on pristine peatlands, whereas on drained peatlands, at least three distinct stages could be identified. Thinnings had only little impact on the stand succession. The new information on stand dynamics may be utilised, e.g. in forest management planning to facilitate the allocation of the growth resources to the desired crop component by appropriate silvicultural treatments, as well as assist in assessing the effects of the climate change on the forested boreal peatlands.

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Inorganic–organic clays (IOCs), clays intercalated with both organic cations such as cationic surfactants and inorganic cations such as metal hydroxy polycations have the properties of both organic and pillared clays, and thereby the ability to remove both inorganic and organic contaminants from water simultaneously. In this study, IOCs were synthesised using three different methods with different surfactant concentrations. Octadecyltrimethylammonium bromide (ODTMA) and hydroxy aluminium ([Al13O4 (OH)24(H2O)12]7+ or Al13) are used as the organic and inorganic modifiers (intercalation agents). According to the results, the interlayer distance, the surfactant loading amount and the Al/Si ratio of IOCs strictly depend on the intercalation method and the intercalation agent ratio. Interlayers of IOCs synthesised by intercalating ODTMA before Al13 and IOCs synthesised by simultaneous intercalation of ODTMA and Al13 were increased with increasing the ODTMA concentration used in the synthesis procedure and comparatively high loading amounts could be observed in them. In contrast, Al/Si decreased with increasing ODTMA concentration in these two types of IOCs. The results suggest that Al-pillars can be fixed within the interlayers by calcination and any increment in the amount of ODTMA used in the synthesis procedure did not affect the interlayer distance of the IOCs. Overall the study provides valuable insights into the structure and properties of the IOCs and their potential environmental applications.

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(i) Incistrans pairs of cyclic 1,3-dicarboxylic acid ethyl esters thecis-foms exhibit higher O-methylene proton (HA, HB) anisochrony than thetrans-forms; (ii) anisochrony, easily observed in certain decalin-10-carboxylic ethyl esters, ‘disappears’ on one of the rings attaining the possibility of transforming into a ‘twist’ form; (iii) in certain pairs of chiralsecethyl esters and theirtert-methylated analogues anisochrony is higher in the latter, contrary to expectation, while, in certain others, the reverse is observed. Attempted explanations are based on assessments whether H A and H B are or are not in highly different magnetic environments in confomers regarded as preferred. This subsumes the possibility thatXYZC-CO2H A H B Me chiral ethyl acetates differ fromXYZC-CH A H B Me ethanes because intervention by the carboxyl group insulates the prochiral centre and allows anisotropic effects to gain somewhat in importance among mechanisms that discriminate between H A and H B so long as rotamerpopulation inequalities persist. Background information on why rotamer-population inequalities will always persist and on a heuristic that attempts to generalize the effects ofXYZ inXYZC - CU AUB V is provided. Possible effects when connectivity exists between a pair amongX, Y, Z or when specific interactions occur betweenV andX, Y orZ are considered. An interpretation in terms of ‘increasing conformational mobility’ has been suggested for the observed increase in the rate of temperature-dependence of O-methylene anisochrony down a series of chiral ethyl esters.

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The potato virus A (PVA) genome linked protein (VPg) is a multifunctional protein that takes part in vital infection cycle events such as replication and movement of the virus from cell to cell. VPg is attached to the 5´ end of the genome and is carried in the tip structure of the filamentous virus particle. VPg is also the last protein to be cleaved from the polyprotein. VPg interacts with several viral and host proteins and is phosphorylated at several positions. These features indicate a central role in virus epidemiology and a requirement for an efficient but flexible mechanism for switching between different functions. -- This study examines some of the key VPg functions in more detail. Mutations in the positively charged region from Ala38 to Lys44 affected the NTP binding, uridylylation, and in vitro translation inhibition activities of VPg, whereas in vivo translation inhibition was not affected. Some of the data generated in this study implicated the structural flexibility of the protein in functional activities. VPg lacks a rigid structure, which could allow it to adapt conformationally to different functions as needed. A major finding of this study is that PVA VPg belongs to the class of ´intrinsically disordered proteins´ (IDPs). IDPs are a novel protein class that has helped to explain the observed lack of structure. The existence of IDPs clearly shows that proteins can be functional and adapt a native fold without a rigid structure. Evidence for the intrinsic disorder of VPg was provided by CD spectroscopy, NMR, fluorescence spectroscopy, bioinformatic analysis, and limited proteolytic digestion. The structure of VPg resembles that of a molten globule-type protein and has a hydrophobic core domain. Approximately 50% of the protein is disordered and an α-helical stabilization of these regions has been hypothesized. Surprisingly, VPg structure was stabilized in the presence of anionic lipid vesicles. The stabilization was accompanied by a change in VPg structure and major morphological modifications of the vesicles, including a pronounced increase in the size and appearance of pore or plaque like formations on the vesicle surface. The most likely scenario seems to be an α-helical stabilization of VPg which induces formation of a pore or channel-like structure on the vesicle surface. The size increase is probably due to fusion or swelling of the vesicles. The latter hypothesis is supported by the evident disruption of the vesicles after prolonged incubation with VPg. A model describing the results is presented and discussed in relation to other known properties of the protein.

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The structures of (1→3),(1→4)-β-D-glucans of oat bran, whole-grain oats and barley and processed foods were analysed. Various methods of hydrolysis of β-glucan, the content of insoluble fibre of whole grains of oats and barley and the solution behaviour of oat and barley β-glucans were studied. The isolated soluble β-glucans of oat bran and whole-grain oats and barley were hydrolysed with lichenase, an enzyme specific for (1→3),(1→4)-β-D-β-glucans. The amounts of oligosaccharides produced from bran were analysed with capillary electrophoresis and those from whole-grains with high-performance anion-exchange chromatography with pulse-amperometric detection. The main products were 3-O-β-cellobiosyl-D-glucose and 3-O-β-cellotriosyl-D-glucose, the oligosaccharides which have a degree of polymerisation denoted by DP3 and DP4. Small differences were detected between soluble and insoluble β-glucans and also between β-glucans of oats and barley. These differences can only be seen in the DP3:DP4 ratio which was higher for barley than for oat and also higher for insoluble than for soluble β-glucan. A greater proportion of barley β-glucan remained insoluble than of oat β-glucan. The molar masses of soluble β-glucans of oats and barley were the same as were those of insoluble β-glucans of oats and barley. To analyse the effects of cooking, baking, fermentation and drying, β-glucan was isolated from porridge, bread and fermentate and also from their starting materials. More β-glucan was released after cooking and less after baking. Drying decreased the extractability for bread and fermentate but increased it for porridge. Different hydrolysis methods of β-glucan were compared. Acid hydrolysis and the modified AOAC method gave similar results. The results of hydrolysis with lichenase gave higher recoveries than the other two. The combination of lichenase hydrolysis and high-performance anion-exchange chromatography with pulse-amperometric detection was found best for the analysis of β-glucan content. The content of insoluble fibre was higher for barley than for oats and the amount of β-glucan in the insoluble fibre fraction was higher for oats than for barley. The flow properties of both water and aqueous cuoxam solutions of oat and barley β-glucans were studied. Shear thinning was stronger for the water solutions of oat β-glucan than for barley β-glucan. In aqueous cuoxam shear thinning was not observed at the same concentration as in water but only with high concentration solutions. Then the viscosity of barley β-glucan was slightly higher than that of oat β-glucan. The oscillatory measurements showed that the crossover point of the G´ and G´´ curves was much lower for barley β-glucan than for oat β-glucan indicating a higher tendency towards solid-like behaviour for barley β-glucan than for oat β-glucan.

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Organisations are increasingly introducing sustainability policies to encourage environmentally friendly behaviours. Employees' green work climate perceptions (i.e., how they perceive their organisations' and co-workers' orientations towards environmental sustainability) may constitute psychological mechanisms that link such policies with behaviour. We present findings of a study on relationships among the perceived presence of organisational sustainability policies, green work climate perceptions and employee reports of their green behaviour (EGB). We hypothesised that green work climate perceptions mediate the positive relationship between employees' perceptions of the presence of a sustainability policy and EGB. Results based on data from 168 employees supported our hypotheses. Green work climate perceptions of the organisation and of co-workers differentially mediated the effects of the perceived presence of a sustainability policy on task-related and proactive EGB. These findings extend research on the efficacy of sustainability policies by shedding new light on the psychological mechanisms that link them with EGB.

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Future time perspective - the way individuals perceive their remaining time in life - importantly influences socio-emotional goals and motivational outcomes. Recently, researchers have called for studies that investigate relationships between personality and future time perspective. Using a cross-lagged panel design, this study investigated effects of chronic regulatory focus dimensions (promotion and prevention orientation) on future time perspective dimensions (focus on opportunities and limitations). Survey data were collected two times, separated by a 3. month time lag, from 85 participants. Results of structural equation modeling showed that promotion orientation had a positive lagged effect on focus on opportunities, and prevention orientation had a positive lagged effect on focus on limitations.