950 resultados para Zero reference level


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Maize is a highly important crop to many countries around the world, through the sale of the maize crop to domestic processors and subsequent production of maize products and also provides a staple food to subsistance farms in undeveloped countries. In many countries, there have been long-term research efforts to develop a suitable hardness method that could assist the maize industry in improving efficiency in processing as well as possibly providing a quality specification for maize growers, which could attract a premium. This paper focuses specifically on hardness and reviews a number of methodologies as well as important biochemical aspects of maize that contribute to maize hardness used internationally. Numerous foods are produced from maize, and hardness has been described as having an impact on food quality. However, the basis of hardness and measurement of hardness are very general and would apply to any use of maize from any country. From the published literature, it would appear that one of the simpler methods used to measure hardness is a grinding step followed by a sieving step, using multiple sieve sizes. This would allow the range in hardness within a sample as well as average particle size and/or coarse/fine ratio to be calculated. Any of these parameters could easily be used as reference values for the development of near-infrared (NIR) spectroscopy calibrations. The development of precise NIR calibrations will provide an excellent tool for breeders, handlers, and processors to deliver specific cultivars in the case of growers and bulk loads in the case of handlers, thereby ensuring the most efficient use of maize by domestic and international processors. This paper also considers previous research describing the biochemical aspects of maize that have been related to maize hardness. Both starch and protein affect hardness, with most research focusing on the storage proteins (zeins). Both the content and composition of the zein fractions affect hardness. Genotypes and growing environment influence the final protein and starch content and. to a lesser extent, composition. However, hardness is a highly heritable trait and, hence, when a desirable level of hardness is finally agreed upon, the breeders will quickly be able to produce material with the hardness levels required by the industry.

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Several intelligent transportation systems (ITS) were used with an advanced driving simulator to assess its influence on driving behavior. Three types of ITS interventions were tested: video in vehicle, audio in vehicle, and on-road flashing marker. The results from the driving simulator were inputs for a developed model that used traffic microsimulation (VISSIM 5.4) to assess the safety interventions. Using a driving simulator, 58 participants were required to drive through active and passive crossings with and without an ITS device and in the presence or absence of an approaching train. The effect of changes in driver speed and compliance rate was greater at passive crossings than at active crossings. The slight difference in speed of drivers approaching ITS devices indicated that ITS helped drivers encounter crossings in a safer way. Since the traffic simulation was not able to replicate a dynamic speed change or a probability of stopping that varied depending on ITS safety devices, some modifications were made to the traffic simulation. The results showed that exposure to ITS devices at active crossings did not influence drivers’ behavior significantly according to the traffic performance indicator, such as delay time, number of stops, speed, and stopped delay. However, the results of traffic simulation for passive crossings, where low traffic volumes and low train headway normally occur, showed that ITS devices improved overall traffic performance.

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Background: Standard methods for quantifying IncuCyte ZOOM™ assays involve measurements that quantify how rapidly the initially-vacant area becomes re-colonised with cells as a function of time. Unfortunately, these measurements give no insight into the details of the cellular-level mechanisms acting to close the initially-vacant area. We provide an alternative method enabling us to quantify the role of cell motility and cell proliferation separately. To achieve this we calibrate standard data available from IncuCyte ZOOM™ images to the solution of the Fisher-Kolmogorov model. Results: The Fisher-Kolmogorov model is a reaction-diffusion equation that has been used to describe collective cell spreading driven by cell migration, characterised by a cell diffusivity, D, and carrying capacity limited proliferation with proliferation rate, λ, and carrying capacity density, K. By analysing temporal changes in cell density in several subregions located well-behind the initial position of the leading edge we estimate λ and K. Given these estimates, we then apply automatic leading edge detection algorithms to the images produced by the IncuCyte ZOOM™ assay and match this data with a numerical solution of the Fisher-Kolmogorov equation to provide an estimate of D. We demonstrate this method by applying it to interpret a suite of IncuCyte ZOOM™ assays using PC-3 prostate cancer cells and obtain estimates of D, λ and K. Comparing estimates of D, λ and K for a control assay with estimates of D, λ and K for assays where epidermal growth factor (EGF) is applied in varying concentrations confirms that EGF enhances the rate of scratch closure and that this stimulation is driven by an increase in D and λ, whereas K is relatively unaffected by EGF. Conclusions: Our approach for estimating D, λ and K from an IncuCyte ZOOM™ assay provides more detail about cellular-level behaviour than standard methods for analysing these assays. In particular, our approach can be used to quantify the balance of cell migration and cell proliferation and, as we demonstrate, allow us to quantify how the addition of growth factors affects these processes individually.

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The response of vegetative soybean (Glycine max) to Helicoverpa armigera feeding was studied in irrigated field cages over three years in eastern Australia to determine the relationship between larval density and yield loss, and to develop economic injury levels. Rather than using artificial defoliation techniques, plants were infested with either eggs or larvae of H. armigera, and larvae allowed to feed until death or pupation. Larvae were counted and sized regularly and infestation intensity was calculated in Helicoverpa injury equivalent (HIE) units, where 1 HIE was the consumption of one larva from the start of the infestation period to pupation. In the two experiments where yield loss occurred, the upper threshold for zero yield loss was 7.51 ± 0.21 HIEs and 6.43 ± 1.08 HIEs respectively. In the third experiment, infestation intensity was lower and no loss of seed yield was detected up to 7.0 HIEs. The rate of yield loss/HIE beyond the zero yield loss threshold varied between Experiments 1 and 2 (-9.44 ± 0.80 g and -23.17 ± 3.18 g, respectively). H. armigera infestation also affected plant height and various yield components (including pod and seed numbers and seeds/pod) but did not affect seed size in any experiment. Leaf area loss of plants averaged 841 and 1025 cm2/larva in the two experiments compared to 214 and 302 cm2/larva for cohort larvae feeding on detached leaves at the same time, making clear that artificial defoliation techniques are unsuitable for determining H. armigera economic injury levels on vegetative soybean. Analysis of canopy leaf area and pod profiles indicated that leaf and pod loss occurred from the top of the plant downwards. However, there was an increase in pod numbers closer to the ground at higher pest densities as the plant attempted to compensate for damage. Defoliation at the damage threshold was 18.6 and 28.0% in Experiments 1 and 2, indicating that yield loss from H. armigera feeding occurred at much lower levels of defoliation than previously indicated by artificial defoliation studies. Based on these results, the economic injury level for H. armigera on vegetative soybean is approximately 7.3 HIEs/row-metre in 91 cm rows or 8.0 HIEs/m2.

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We present a comparative study of the low temperature electrical transport properties of the carbon matrix containing iron nanoparticles and the films. The conductivity of the nanoparticles located just below the metal-insulator transition exhibits metallic behavior with a logarithmic temperature dependence over a large temperature interval. The zero-field conductivity and the negative magnetoresistance, showing a characteristic upturn at liquid helium temperature, are consistently explained by incorporating the Kondo relation and the two dimensional electron-electron interaction. The films, in contrast, exhibit a crossover of the conductivity from power-law dependence at high temperatures to an activated hopping law dependence in the low temperature region. The transition is attributed to changes in the energy dependence of the density of states near the Fermi level. The observed magnetoresistance is discussed in terms of quantum interference effect on a three-dimensional variable range hopping mechanism.

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In this paper, a novel 12-sided polygonal space vector structure is proposed for an induction motor drive. The space vector pattern presented in this paper consists of two 12-sided concentric polygons with the outer polygon having a radius double the inner one. As compared to previously reported 12-sided polygonal space vector structures, this paper subdivides the space vector plane into smaller sized triangles. This helps in reducing the switching frequency of the inverters without deteriorating the output voltage quality. It also reduces the device ratings and dv/dt stress on the devices to half. At the same time, other benefits obtained from the existing 12-sided space vector structure, such as increased linear modulation range and complete elimination of 5th and 7th order harmonics in the phase voltage, are also retained in this paper. The space vector structure is realized by feeding an open-end induction motor with two conventional three-level neutral point clamped (NPC) inverters with asymmetric isolated dc link voltage sources. The neutral point voltage fluctuations in the three-level NPC inverters are eliminated by utilizing the switching state multiplicities for a space vector point. The pulsewidth modulation timings are calculated using sampled reference waveform amplitudes and are explained in detail in this paper. Experimental verification on a laboratory prototype shows that this configuration may be considered suitable for high power drives.

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Identifying species boundaries within morphologically indistinguishable cryptic species complexes is often contentious. For the whitefly Bemisia tabaci (Gennadius) (Hemiptera: Sternorrhyncha: Aleyrodoidea: Aleyrodidae), the lack of a clear understanding about the genetic limits of the numerous genetic groups and biotypes so far identified has resulted in a lack of consistency in the application of the terms, the approaches use to apply them and in our understanding of what genetic structure within B. tabaci means. Our response has been to use mitochondrial gene cytochrome oxidase one to consider how to clearly and consistently define genetic separation. Using Bayesian phylogenetic analysis and analysis of sequence pairwise divergence we found a considerably higher to number of genetic groups than had been previously determined with two breaks in the distribution, one at 11% and another at 3.5%. At >11% divergence, 11 distinct groups were resolved, whereas at >3.5% divergence 24 groups were identified. Consensus sequences for each of these groups were determined and were shown to be useful in the correct assignment of sequences of unknown origin. The 3.5% divergence bound is consistent with species level separations in other insect taxa and Suggests that B. tabaci is it cryptic species composed of at least 24 distinct species. We further show that the placement of Bemesia atriplex (Froggatt) within the B. tabaci in, group adds further weight to the argument for species level separation within B. tabaci. This new analysis, which constructs consensus sequences and uses these its a standard against which unknown sequences call be compared, provides for the first time it consistent means of identifying the genetic hounds of each species with it high degree of certainty.

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I have more often thought over what I am thinking and also I have often told it to others - professional development and collegial feedback on kindergarten teams. The need for professional feedback surfaces year after year in enquiries made among staff members in the field of early childhood education. Because the pressure to be effective adds to the workload of the heads of kindergartens, there are few opportunities to give staff concrete feedback on a daily basis. Because peers are able to observe each other close at hand, their reciprocal feedback can compensate for that of the kindergarten head. In this study the practical training process of collegial feedback is studied and also the opportunities for feedback as a means of supporting professional development in the context of kindergarten. The development project involving the entire kindergarten community (N=21) was implemented in 2003-2004 through three developing cycles. The Johar´s Window , produced by Luft and Jung with the Model of Situational Leadership by Hersey and Blanchard, acted as a theoretical frame of reference. It has been used in this study both for its qualitative and its quantitative methods. The data were carried out through questions, interviews, diaries, written descriptions and monthly evaluations. The qualitative and quantitative methods were also used in analysing the data. The results showed that during the training process, the staff as a giver of feedback moved from the professional basic level to the professional maturity level. Their awareness of both their own and their peers´ know-how expanded from the initial state to the final state. It became evident that team size is the essential key element in the practise of giving feedback to team members. The team atmosphere and the commitment of the team members are in significant factors in the training of giving and receiving feedback. As a result of analyses, delivering feedback was grouped into three categories: developmental feedback, descriptive feedback and either supportive or destructive feedback. Receiving feedback was likewise groupped into three categories: aspiring to develop, unaccommodating and accepting. The ability to control feelings improved along with the skills of giving feedback; it was possible to analyse development through the professional development model represented in the theory of the study. The results showed that professional know-how of other kinds also developed during the process. Giving feedback among fellow workers enables team members to receive feedback everyday. Training to give feedback means examining a field of professional know-how and also formulating shared rules. The results of this study give support to previous studies that have emphasised practical training in natural circumstances. Keywords: feedback, professional development, learning at work

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In this study the researcher wanted to show the observed connection of mathematics and textile work. To carry this out the researcher designed a textbook by herself for the upper secondary school in Tietoteollisuuden Naiset TiNA project at Helsinki University of Technology (URL:http://tina.tkk.fi/). The assignments were designed as additional teaching material to enhance and reinforce female students confidence in mathematics and in the management of their textile work. The research strategy applied action research, out of which two cycles two have been carried out. The first cycle consists of establishing the textbook and in the second cycle its usability is investigated. The third cycle is not included in this report. In the second cycle of the action research the data was collected from 15 teachers, five textile teachers, four mathematics teachers and six teachers of both subjects. They all got familiar with the textbook assignments and answered a questionnaire on the basis of their own teaching experience. The questionnaire was established by applying the theories of usability and teaching material assessment study. The data consisted of qualitative and quantitative information, which was analysed by content analysis with computer assisted table program to either qualitative or statistical description. According to the research results, the textbook assignments seamed to be applied better to mathematics lessons than textile work. The assignments pointed out, however, the clear interconnectedness of textile work and mathematics. Most of the assignments could be applied as such or as applications in the upper secondary school textile work and mathematics lessons. The textbook assignments were also applicable in different stages of the teaching process, e.g. as introduction, repetition or to support individual work or as group projects. In principle the textbook assignments were in well placed and designed in the correct level of difficulty. Negative findings concerned some too difficult assignments, lack of pupil motivation and unfamiliar form of task for the teacher. More clarity for some assignments was wished for and there was especially expressed a need for easy tasks and assignments in geometry. Assignments leading to the independent thinking of the pupil were additionally asked for. Two important improvements concerning the textbook attainability would be to get the assignments in html format over the Internet and to add a handicraft reference book.

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A total of 63 isolates of Pasteurella multocida from Australian poultry, all associated with fowl cholera outbreaks, and three international reference strains, representing the three subspecies within P. multocida were used to develop a multi-locus sequence typing scheme. Primers were designed for conserved regions of seven house-keeping enzymes - adk, est, gdh, mdh, pgi, pmi and zwf - and internal fragments of 570-784 bp were sequenced for all isolates and strains. The number of alleles at the different loci ranged from 11 to 20 and a total of 29 allelic profiles or sequence types were recognised amongst the 66 strains. There was a strong concordance between the MLST data and the existing multi-locus enzyme electrophoresis and ribotyping data. When used to study a sub-set of isolates with a known detailed epidemiological history, the MLST data matched the results given by restriction endonuclease analysis, pulsed-field gel electrophoresis, ribotyping and REP-PCR. The MLST scheme provides a high level of resolution and is an excellent tool for studying the population structure and epidemiology of P. multocida.

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The Best Use Modelling for Sustainable Australian Sports Field Surfaces project has achieved significant success. The project has attracted participation from councils throughout Australia, with in excess of 300 sports fields evaluated from 18 councils to date. An important project component is the derivation of a recommended standard procedure for specifying the performance of playing surfaces. An associated step has been to establish recommended playing surface performance standards for community level sports fields. The derived modelling also provides information on the expected usage and associated costs of different sports surface development options. This is expected to assist the Australian turf production industry through demonstrating to councils that cost effective natural turf options exist that can meet higher usage expectation (as a viable alternative to synthetic turf). A web-accessed data base system will be made available to councils from January 2010 on (reference to www.passturf.com). This system will enable participating councils to record and analyse field performance over time. The system is considered world-leading, and will help keep the Australian parks industry to the international forefront. Tools developed as part of the project offer councils the opportunity to internally assess the performance of their current sports field provision, to identify any deficiencies and to determine the best corrective measure if any deficiency is identified. This is expected to offer community benefits to both sports facility providers and facility user groups. In turn this will aid the provision of affordable community access to safe and good quality playing surfaces. Tools and associated information material will be made available to councils throughout Australia by the end of this year, via the Parks and Leisure Aust. web site. The Best Use Modelling Project is work in progress. On-going input will be needed to ensure the web-accessed database software is as user friendly as possible, new performance testing data will need to be inputted, and tools provided to participating councils updated. Through the support of HAL there is now a well-structured, nationally-supported system in place for benchmarking playing surfaces and for assisting councils to optimise their resource allocation to sports field upgrade or maintenance work.

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3d and 4d core-level XPS spectra for CePd3, a mixed-valence system, have been measured. Each spectrum exhibits two sets of structures, each corresponding to one of the valence states of cerium. Thus the usefulness of XPS, which has so far not been used extensively to investigate the mixed-valence cerium systems, is pointed out.

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The educational reform, launched in Finland in 2008, concerns the implementation of the Special Education Strategy (Opetusministeriö 2007) under an improvement initiative called Kelpo. One of the main proposed alterations of the Strategy relates to the support system of comprehensive school pupils. The existed two-level model (general and special support) is to be altered by the new three-level model (general, intensified and special support). There are 233 municipalities involved nationwide in the Kelpo initiative, each of which has a municipal coordinator as a national delegate. The Centre for Educational Assessment [the Centre] at the University of Helsinki, led by Professor Jarkko Hautamäki, carries out the developmental assessment of the initiative’s developmental process. As a part of that assessment the Centre interviewed 151 municipal coordinators in November 2008. This thesis considers the Kelpo initiative from Michael Fullan’s change theory’s aspect. The aim is to identify the change theoretical factors in the speech of the municipal coordinators interviewed by the Centre, and to constitute a view of what the crucial factors in the reform implementation process are. The appearance of the change theoretical factors, in the coordinators’ speech, and the meaning of these appearances are being considered from the change process point of view. The Centre collected the data by interviewing the municipal coordinators (n=151) in small groups of 4-11 people. The interview method was based on Vesala and Rantanen’s (2007) qualitative attitude survey method which was adapted and evolved for the Centre’s developmental assessment by Hilasvuori. The method of the analysis was a qualitative theory-based content analysis, processed using the Atlas.ti software. The theoretical frame of reference was grounded on Fullan’s change theory and the analysis was based on three change theoretical categories: implementation, cooperation and perspectives in the change process. The analysis of the interview data revealed spoken expressions in the coordinators’ speech which were either positively or negatively related to the theoretical categories. On the grounds of these change theoretical relations the existence of the change process was observed. The crucial factors of reform implementation were found, and the conclusion is that the encounter of the new reform-based and already existing strategies in school produces interface challenges. These challenges are particularly confronted in the context of the implementation of the new three-level support model. The interface challenges are classified as follows: conceptual, method-based, action-based and belief-based challenges. Keywords: reform, implementation, change process, Michael Fullan, Kelpo, intensified support, special support

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Haemophilus parasuis is the causative agent of Glässer's disease. Up to now 15 serovars of H. parasuis have been identified, with significant differences existing in virulence between serovars. In this study, suppression subtractive hybridization (SSH) was used to identify the genetic difference between Nagasaki (H. parasuis serovar 5 reference strain, highly virulent) and SW114 (H. parasuis serovar 3 reference strain, non-virulent). A total of 191 clones were obtained from the SSH library. Using dot hybridization and PCR, 15 clones were identified containing fragments that were present in the Nagasaki genome while absent in the SW114 genome. Among these 15 fragments, three fragments (ssh1, ssh13, ssh15) encode cell surface-associated components; three fragments (ssh2, ssh5, ssh9) are associated with metabolism and stress response; one fragment (ssh8) is involved in assembly of fimbria and one fragment (ssh6) is a phage phi-105 ORF25-like protein. The remaining seven fragments are hypothetical proteins or unknown. Based on PCR analysis of the 15 serovar reference strains, eight fragments (ssh1, ssh2, ssh3, ssh6, ssh8, ssh10, ssh11 and ssh12) were found in three to five of most virulent serovars (1, 5, 10, 12, 13 and 14), zero to two in three moderately virulent serovars (2, 4 and 15), but absent in the low virulent serovar (8) and non-virulent serovars (3, 6, 7, 9 and 11). In vivo transcription fragments ssh1, ssh2, ssh8 and ssh12 were identified in total RNA samples extracted from experimental infected pig lung by RT-PCR. This study has provided some evidence of genetic differences between H. parasuis strains of different virulence.