969 resultados para Railroads, Local and light


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The thesis explores global and national-level issues related to the development of markets for biomass for energy. The thesis consists of five separate papers and provides insights on selected issues. The aim of Paper I was to identify methodological and statistical challenges in assessing international solid and liquid biofuels trade and provide an overview of the Finnish situation with respect to the status of international solid and liquid biofuels trade. We found that, for the Finnish case, it is possible to qualify direct and indirect trade volumes of biofuels. The study showed that indirect trade of biofuels has a highly significant role in Finland and may be a significant sector also in global biofuels trade. The purpose of Paper II was to provide a quantified insight into Finnish prospects for meeting the national 2020 renewable energy targets and concurrently becoming a largescale producer of forest-biomass-based second-generation biofuels for feeding increasing demand in European markets. We found that Finland has good opportunities to realise a scenario to meet 2020 renewable energy targets and for large-scale production of wood-based biofuels. The potential net export of transport biofuels from Finland in 2020 would correspond to 2–3% of European demand. Paper III summarises the global status of international solid and liquid biofuels trade as illuminated by several separate sources. International trade of biofuels was estimated at nearly 1 EJ for 2006. Indirect trade of biofuels through trading of industrial roundwood and material by-products comprises the largest proportion of the trading, with a share of about two thirds. The purpose of Paper IV was to outline a comprehensive picture of the coverage of various certification schemes and sustainability principles relating to the entire value-added chain of biomass and bioenergy. Regardless of the intensive work that has been done in the field of sustainability schemes and principles concerning use of biomass for energy, weaknesses still exist. The objective of Paper V was to clarify the alternative scenarios for the international biomass market until 2020 and identify the underlying steps needed toward a wellfunctioning and sustainable market for biomass for energy purposes. An overall conclusion drawn from this analysis concerns the enormous opportunities related to the utilisation of biomass for energy in the coming decades.

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Bauhinia variegata and B. variegata var. candida, commonly known as orchid trees, are small sized trees widely used for urban forestry and landscaping. Adult plants grow under full sun; in Brazil, however, seedlings are generally cultivated in commercial nurseries under natural half-shading. The objective of this study was to evaluate the influence of different colored shade nets and light conditions on the initial growth of B. variegata and B. variegata var. candida. The influence of six light conditions (red net with 50% shading; blue net with 50% shading; black net with 70% shading; black net with 50% shading; black net with 30% shading; and full sun) on the initial growth of B. variegata and B. variegata var. candida were evaluated along 160 days, and growth relationships were calculated. Seedlings showed more efficiency on the use of photoassimilated compounds when grown under full sun. Such condition is the most appropriate for seedling production of B. variegata and B. variegata var. candida, contradicting what has been performed in practice.

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We are using molecular, biochemical, and genetic approaches to study the structural and regulatory genes controlling the assimilation of inorganic nitrogen into the amino acids glutamine, glutamate, aspartate and asparagine. These amino acids serve as the principal nitrogen-transport amino acids in most crop and higher plants including Arabidopsis thaliana. We have begun to investigate the regulatory mechanisms controlling nitrogen assimilation into these amino acids in plants using molecular and genetic approaches in Arabidopsis. The synthesis of the amide amino acids glutamine and asparagine is subject to tight regulation in response to environmental factors such as light and to metabolic factors such as sucrose and amino acids. For instance, light induces the expression of glutamine synthetase (GLN2) and represses expression of asparagine synthetase (ASN1) genes. This reciprocal regulation of GLN2 and ASN1 genes by light is reflected at the level of transcription and at the level of glutamine and asparagine biosynthesis. Moreover, we have shown that the regulation of these genes is also reciprocally controlled by both organic nitrogen and carbon metabolites. We have recently used a reverse genetic approach to study putative components of such metabolic sensing mechanisms in plants that may be conserved in evolution. These components include an Arabidopsis homolog for a glutamate receptor gene originally found in animal systems and a plant PII gene, which is a homolog of a component of the bacterial Ntr system. Based on our observations on the biology of both structural and regulatory genes of the nitrogen assimilatory pathway, we have developed a model for metabolic control of the genes involved in the nitrogen assimilatory pathway in plants.

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Previous studies have demonstrated the high reproducibility of heart rate variability (HRV) measures in adults while little information exists concerning HRV reproducibility in children. Subsequently, the aim of the current study was to examine the moderate-term reproducibility of heart rate and frequency domain measures of HRV during rest and light to moderate exercise in children. Ten healthy children (6 males, 4 females) aged between 7 and 12 years of age volunteered for this study with HRV recordings obtained during supine rest and three treadmill walking exercise work rates (≤60% maximum heart rate), initially and then 8 weeks later. Differences (P < 0.05) between variables were examined using paired t-tests or Wilcoxon signed rank tests while reliability and reproducibility were examined by intraclass correlation coefficients (ICC), coefficients of variation (CV), and mean bias ratio and ratio limits of agreement (LOA). Heart rate and all measures of HRV at rest and exercise were unchanged after 8 weeks. Significant ICC were documented primarily during rest (0.72-0.85) while weaker relationships (-0.02-0.87) were evident during exercise. A large range of CV was identified during rest (6-33%) and exercise (3-128%) while the ratio LOA were variable and substantial (1.04-2.73). Despite similar HRV over an 8-week period, variable ICC and sizable CV and ratio LOA indicate moderate to poor reproducibility of HRV in children, particularly during light to moderate exercise. Studies examining HRV in children should include age- or maturation stage-matched control participants to address the age-related change in HRV and inadequate HRV reliability.

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Tämä tutkielma käsittelee paikkamarkkinointia ja paikkabrändäystä. Tutkielmassa tarkastellaan paikallisen ja turistin tapoja muodostaa kaupunkibrändi; mistä palasista brändi muodostuu kirjallisuuden ja haastateltavien mukaan, koetaanko eri palaset vaihtelevissa määrin tärkeiksi riippuen siitä, tarkastellaanko paikkaa paikallisena vai turistina, ja löytyykö jotain yhteisiä retorisia nimittäjiä sille, miten kotikaupungista puhutaan verrattuna lomakaupunkiin. Tutkimuksessa haastateltiin yli kolmeakymmentä henkilöä heidän kotikaupungeistaan ja kaupungeista, joihin he olivat matkustaneet lomalle. Haastateltavat olivat suurinpiirtein samanikäisiä, mutta eri kaupungeista ja matkustaneet eri paikkoihin. Haastateltavia pyydettiin ensin kuvailemaan vapaasti kotikaupunkiaan ja sen jälkeen kaupungista kysyttiin kirjallisuuteen perustuen kysymyksiä. Sama menetelmä toistettiin lomakohteen suhteen. Tutkimuksesta selvisi, että paikkabrändi muodostetaan samoista komponenteista, mutta joidenkin komponenttien merkitys on tärkeämpi kotikaupungissa, kun taas toiset komponentit ovat tärkeitä lomakohteen suhteen. Ihmiset ja kulttuuri yleisesti koettiin tärkeinä komponentteina molemmista paikkabrändeistä puhuttaessa, kun taas kotikaupungin brändinmuodostukseen kuului vahvemmin lait ja muut käytännölliset menettelytavat kuten liikenteen toimivuus. Lomakohteen brändinmuodostuksessa vapaudella tehdä mitä haluaa oli suuri merkitys ja vapautta nähtiin eri muodoissa. Retoriikka kotikaupungista puhuttaessa oli selvästi negatiivista, kun taas lomakohteesta puhuttiin yleisesti ottaen positiiviseen sävyyn. Suhde kotikaupunkiin oli ambivalentti, sillä huonojakin puolia mainittaessa niitä puolusteltiin, tai kotikaupungista mainittiin loppujen lopuksi jotain hyvää. Tutkimusten tuloksiin perustuen toimenpidesuosituksina ehdotetaan olemassaolevan autenttisen kulttuurin ylläpitämäistä, korostamista ja kaupungin orgaanista kehittämistä suuntaan, jossa se on hyvä paikka niin elämiseen kuin lomailuun. Identiteetti, imago ja ihmiset kietoutuvat tiiviisti yhteen, minkä vuoksi kaupunkisuunnittelun- ja kehittämisen tehtävänä on pitää huolta, että kaupunki on onnistunut molempien ryhmien suhteen, ja molemmat ryhmät levittävät kaupungista positiivista sanomaa.

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The distribution of excitation energy between the two photosystems (PSII and PSI) of photosynthesis is regulated by the light state transition. Three models have been proposed for the mechanism of the state transition in phycobilisome (PBS) containing organisms, two involving protein phosphorylation. A procedure for the rapid isolation of thylakoid membranes and PBS fractions from the cyanobacterium Synechococcus m. PCC 6301 in light state 1 and light state 2 was developed. The phosphorylation of thylakoid and soluble proteins rapidly isolated from intact cells in state 1 and state 2 was investigated. 77 K fluorescence emission spectra revealed that rapidly isolated thylakoid membranes retained the excitation energy distribution characteristic of intact cells in state 1 and state 2. Phosphoproteins were identified by gel electrophoresis of both thylakoid membrane and phycobilisome fractions isolated from cells labelled with 32p orthophosphate. The results showed very close phosphoprotein patterns for either thylakoid membrane or PBS fractions in state 1 and state 2. These results do not support proposed models for the state transition which required phosphorylation of PBS or thylakoid membrane proteins.

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The optical cross section of PS I in whole cells of Porphyridium cruentum (UTEX 161), held in either state 1 or state 2, was determined by measuring the change in absorbance at 820nm, an indication of P700+; the X-section of PS2 was determined by measuring the variable fluorescence, (Fv-Fo)/Fo, from PS2. Both cross-sections were 7 determined by fitting Poisson distribution equations to the light saturation curves obtained with single turnover laser flashes which varied in intensity from zero to a level where maximum yield occurred. Flash wavelengths of 574nm, 626nm, and 668nm were used, energy absorbed by PBS, by PBS and chla, and by chla respectively. There were two populations of both PSi and PS2. A fraction of PSi is associated with PBS, and a fraction of PS2 is free from PBS. On the transition S1->S2, only with PBS-absorbed energy (574nm) did the average X-section of PSi increase (27%), and that of PS2 decrease (40%). The fraction of PSi associated with PBS decreased, from 0.65 to 0.35, and the Xsection of this associated PS 1 increased, from 135±65 A2 to 400±300A2. The cross section of PS2 associated with PBS decreased from 150±50 A2 to 85±45 A2, but the fraction of PS2 associated with PBS, approximately 0.75, did not change significantly. The increase in PSi cross section could not be completely accounted for by postulating that several PSi are associated with a single PBS and that in the transition to state2, fewer PSi share the same number of PBS, resulting in a larger X-section. It is postulated that small changes occur in the attachment of PS2 to PBS causing energy to be diverted to the attached PSi. These experiments support neither the mobile-PBS model of state transitions nor that of spillover. From cross section changes there was no evidence of energy transfer from PS2 to PSi with 668nm light. The decrease in PS2 fluorescence which occurred at this wavelength cannot be explained by energy transfer; another explanation must be sought. No explanation was found for an observed decrease in PSi yield at high flash intensities.

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3-alkyl-2-methoxypyrazines (MPs) are grape- and insect-derived odor-active compounds responsible for vegetative percepts that are detrimental to wine quality when elevated. This study tested both the effect of closure/packaging types and light/temperature storage conditions on MPs (isopropyl-, secbutyl-, and isobutyl-MP) in wine. An MP-emiched wine rapidly (after 140 hours) and significantly decreased in MP concentration after natural and synthetic cork contact (immersion of closures in wine). This decrease was greatest with synthetic closures (70% - 89% reduction) and secbutyl-MP. Subsequently storage trials tested the effects of commercial closure/packaging options (natural cork, agglomerate cork, synthetic corks, screwcaps and TetraPak® cartons) on MPs in MP-emiched Riesling and Cabernet Franc over 18 months. Regardless of packaging, isobutyl-MP was the most altered from bottling. Notably, all MP levels tended to decrease to the greatest extent in TetraPak® cartons (~34% for all MPs) and there was evidence of contribution ofisoproyl- and secbutyl-MP from cork-based closures (i.e. ~30% increase in secbutyl-MP after 6 months) or from an unidentified wine constituent. To test the effects of various light/temperature conditions (light exposed at ambient temperature in three different bottle hues, light excluded at ambient temperature and light excluded at a "cellar" temperature (14°C)), MP-emiched Riesling and Cabernet Franc were also analyzed for MP concentrations over 12 months. MPs did not vary consistently with light or temperature. Other odorants and physico-chemical properties were tested in all wines during storage trials and closely agree with previous literature. These results provide novel insights into MPs during ageing, interactions with packaging and storage conditions, and assist in the selection of storage conditions/packaging for optimal wine quality.

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This paper proposes a content based image retrieval (CBIR) system using the local colour and texture features of selected image sub-blocks and global colour and shape features of the image. The image sub-blocks are roughly identified by segmenting the image into partitions of different configuration, finding the edge density in each partition using edge thresholding, morphological dilation and finding the corner density in each partition. The colour and texture features of the identified regions are computed from the histograms of the quantized HSV colour space and Gray Level Co- occurrence Matrix (GLCM) respectively. A combined colour and texture feature vector is computed for each region. The shape features are computed from the Edge Histogram Descriptor (EHD). Euclidean distance measure is used for computing the distance between the features of the query and target image. Experimental results show that the proposed method provides better retrieving result than retrieval using some of the existing methods

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Integration of inputs by cortical neurons provides the basis for the complex information processing performed in the cerebral cortex. Here, we propose a new analytic framework for understanding integration within cortical neuronal receptive fields. Based on the synaptic organization of cortex, we argue that neuronal integration is a systems--level process better studied in terms of local cortical circuitry than at the level of single neurons, and we present a method for constructing self-contained modules which capture (nonlinear) local circuit interactions. In this framework, receptive field elements naturally have dual (rather than the traditional unitary influence since they drive both excitatory and inhibitory cortical neurons. This vector-based analysis, in contrast to scalarsapproaches, greatly simplifies integration by permitting linear summation of inputs from both "classical" and "extraclassical" receptive field regions. We illustrate this by explaining two complex visual cortical phenomena, which are incompatible with scalar notions of neuronal integration.

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This article examines the politics of place in relation to legal mobilization by the anti-nuclear movement. It examines two case examples - citizens' weapons inspections and civil disobedience strategies - which have involved the movement drawing upon the law in particular spatial contexts. The article begins by examining a number of factors which have been employed in recent social movement literature to explain strategy choice, including ideology, resources, political and legal opportunity, and framing. It then proceeds to argue that the issues of scale, space, and place play an important role in relation to framing by the movement in the two case examples. Both can be seen to involve scalar reframing, with the movement attempting to resist localizing tendencies and to replace them with a global frame. Both also involve an attempt to reframe the issue of nuclear weapons away from the contested frame of the past (unilateral disarmament) towards the more universal and widely accepted frame of international law.

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Extending the season of production and improving the scheduling of ornamental crops are key commercial objectives for nurserymen. In some woody species, the period in which cuttings can be rooted successfully is transient, thus limiting the opportunities for scheduled production. Optimum rooting often occurs in early- to mid-summer coinciding with periods of active shoot growth. The relationship between this shoot activity and root initiation was investigated in Cotinus coggygria 'Royal Purple'. Shoot growth on stock plants was manipulated by altering the photoperiod or light quality. Results indicated there were seasonal effects on rooting, but the importance of shoot activity varied with harvest time. Cuttings harvested in August had high rooting percentages, irrespective of photoperiod, and despite shoot growth terminating in response to the short-day treatment. In contrast, by September, rooting percentage was highest in cuttings from plants under long-days, which had maintained greatest shoot growth activity. Cotinus shoots grown in vitro under 16 h days showed reduced shoot growth and increased rooting competence compared with shoots grown under 8 h days. Growing stock plants under polythene films, which altered the amount and quality of the incident light, influenced the rooting of cuttings harvested in August, but no consistent relationship with shoot activity was apparent. From a practical viewpoint, maintaining shoot activity late in the season may prolong the period for propagation by cuttings; but, from a scientific viewpoint, processes associated with an active shoot apex do not provide a complete explanation of seasonal variation in rooting.

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The effect of temperature on early vegetative growth, leaf chlorophyll fluorescence and chlorophyll content was examined on four genotypes of cacao (Amelonado, AMAZ 15–15, SCA 6 and SPEC 54/1). A controlled environment glasshouse was used to simulate the temperature conditions of three cacao-growing regions (Bahia, Brazil; Tafo, Ghana and Lower Perak, Malaysia) over the course of a year. Base temperatures calculated from increments in main stem growth varied from 18.6°C for AMAZ 15/15 to 20.8°C for SPEC 54/1. Temporal variation in Fv/Fm observed for two of the clones (SCA 6 and SPEC 54/1) in two of the compartments were correlated with temperature differences over time. Significant differences were also recorded between genotypes in leaf chlorophyll content. It was shown that variation over time in leaf chlorophyll content could be quantified accurately as a function of temperature and light integral. The results imply that genetic variability exists in cacao in response to temperature stress.