807 resultados para Ecological competition


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Valproate and carbamazepine (CAR) have been proposed as adjunct alternatives for the control of aggression in psychiatric patients, although no definite conclusions have been reached. We examined the effects of these drugs on food competition offensive aggression and other behaviors in high- and low-aggression food-restricted pigeons. These were divided into pairs containing previously ranked high-aggression (N = 10 pairs) and low-aggression females (N = 10 pairs). In Experiment 1, a pigeon in each pair of high- and low-aggression subjects was treated daily with an oral dose of sodium valproate (50 mg kg-1 mL saline-1) for 15 days. The other animal received the vehicle. On days 1, 7, and 15, food competition trials (10 min) were performed 60 min after treatment. In Experiment 2, one pigeon in each pair was treated daily with an oral dose of CAR (20 mg kg-1 mL saline-1) for 15 days. Each pair was submitted to a food competition trial on days 1, 7, and 15 of treatment. Valproate (15 days of treatment) selectively decreased the time spent in offensive aggression (control: 102.7 ± 9.3 vs valproate: 32.7 ± 9.2 s; P < 0.001, ANOVA-2-TAU) of high-aggression pigeons. This was also the case for 7 and 15 days of CAR treatment (control: 131.5 ± 8.9 vs CAR: 60.4 ± 5.3, P < 0.01, and control: 122.7 ± 7.1 vs CAR: 39.1 ± 5.2; P < 0.001, ANOVA-2-TAU, respectively). Thus, the two anticonvulsive drugs have a similar effect on food competition aggression in pigeons.

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Sweet potato is an important staple, and it is mainly known for its contribution of β-carotene in human diet. The effects of cultivar and habitat on this pigment and other nutritional characteristics of the crop still require investigation. In this study, three locally bred cultivars of sweet potato, two of which are orange-fleshed, were grown in three different agro-ecological areas to determine soluble sugar content, β-carotene, and total antioxidants of roots. In addition antioxidant activity, total carotenoids, and chlorophyll content were determined in edible leaves. Reducing sugars, β-carotene, total antioxidants capacity, total carotenoids, and chlorophyll content were significantly affected by environmental conditions. The location at lower altitude and closer to the coastline showed high evapotranspiration, thus reducing sugar content, antioxidant activity, and phytonutrients in both storage roots and leaves. Absence of water stress in agro-ecological locations further inland and at higher altitudes was associated with an increase in these compounds. Free radical scavenging activity of DPPH was higher in the storage roots (610.49 µmoles TE/100g) than in the leaves (426.06 µmoles TE/100g); nevertheless, opposite results were found for the ferric ion reducing activity (FRAP). The deep orange-fleshed cultivar A45 contained high β-carotene (15 mg/100g), which is enough to meet RDA for vitamin A. There is evidence of agro-ecological effect on sweet potato nutritional value.

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Tutkielman aiheena on EU:n kilpailuoikeudellinen lähestymistapa challenge-lausekkeisiin teknologinsiirtosopimuksia koskevassa ryhmäpoikkeusasetuksessa. Teknologian lisensoinnin katsotaan olevan tärkeä väline teknologian kehityksen levittämisessä ja innovaation edistämisessä. Joissakin tapauksissa lisenssisopimus voi sisältää kilpailua rajoittavia lausekkeita, joiden voidaan kuitenkin nähdä hyödyttävän kilpailua kokonaisuutta arvostellen. Tällaisia lausekkeita ovat niin sanotut ”no-challenge” – lauseke, eli sopimusehto, jonka nojalla lisenssinsaaja sitoutuu olemaan haastamatta lisensoidun immateriaalioikeuden pätevyyttä ja ”termination-on-challenge” – lauseke, joka antaa lisensoijalle haastettaessa oikeuden päättää lisenssisopimus. Tutkielmassa perehdytään challenge -lausekkeiden hyväksyttävyyden arviointiin Euroopan unionin kilpailuoikeuden näkökulmasta uuden 1.5.2014 voimaan tulleen ryhmäpoikkeusasetuksen valossa. Muissa kuin yksinoikeuksia luovissa teknologiansiirtosopimuksissa olevat termination-on-challenge – lausekkeita tulee uusimmassa ryhmäpoikkeusetuksessa aina perustua yritysten itse suorittamaan tapauskohtaiseen arviointiin. No-challenge – lausekkeet ovat jatkossakin aiemman käytännön mukaisesti ryhmäpoikkeuksen soveltamisalan ulkopuolella. Komission on perustellut challenge - lausekkeiden jättämistä asetuksen ulkopuolelle julkisella intressillä, joka on päästä eroon mitättömistä immateriaalioikeuksista. Komission on katsonut, että challenge – lausekkeiden kilpailua rajoittava ominaisuus on mitättömien immateriaalioikeuksien esiintyminen markkinoilla, mikä osaltaan vääristää kilpailua ja hidastaa toimijoiden markkinoille pääsyä. Toisaalta lausekkeiden voidaan sanoa edistävän kilpailua, sillä ne usein tarjoavat immateriaalioikeuden haltijalle riittävän oikeussuojan ja kannustimen lisensoida teknologia, mikä lisää kilpailua, keksijöiden kannustimia panostaa innovaatioihin sekä vähentää transaktiokustannuksia. Tutkielman keskeinen tulos on ennen kaikkea challenge-lausekkeiden kilpailuvaikutusten tunnistamisessa ja komission perusteluiden kriittisessä arvioinnissa. Komission linjauksen perustelut eivät saa riittävää tukea ottaen huomioon vaikutustenarvioinnin, EU:n tuomioistuinkäytännön sekä taloustieteellisen lähestymistavan. Tutkielman tulosten pohjalta ja tukeutuen eri oikeuslähteisiin, taloustieteellisiin argumentteihin ja oikeusvertailevaan tutkimukseen, on mahdollista tehdä johtopäätöksiä niistä seikoista ja argumenteista, joilla on merkitystä uuden politiikkalinjauksen kilpailuvaikutuksiin.

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Seed vigor is one of the factors that determines the speed and uniformity of seedling emergence and initial plant growth, which are crucial aspects in the competition against weeds. The objective of this study was to verify the direct effects of soybean seed vigor on weed competition and grain yield. A field experiment was conducted with three seed lots of the "Conquista" cultivar, previously characterized by physiological tests as having high, intermediate and low vigor. The experiment was divided into weeded and unweeded plots with six treatments. Crop plant height, weed dry mass accumulation and crop grain yield data were recorded. Seed vigor did not affect plant height and grain yield. Plants which developed from seeds with high and intermediate vigor showed the best results for competition against weeds, reducing weed dry mass accumulation. Plants which developed from high vigor seeds give the best results for grain yield for both weeded and unweeded treatments.

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The financial sector has been viewed traditionally as either providing the "oil" for the "wheels of commerce" or as a parasite on the real sector of the economy where real productivity gains provide for increasing real wages and per capita incomes. The present paper takes a different route and attempts to an analysis of financial institutions on a par with the production sector of the economy. It also develops a link which amalgamates "the knowledge-based" perspective on firms' operations with Schumpeterian financial leverage to exploit productivity enhancing innovations, and Minsky's tendency towards financial fragility. The analysis also leads to some policy recommendations concerning financial regulation, risk management and financial institution's building.

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This paper surveys the literature on fiscal competition. We consider tax and expenditure competition in a more general set up where different jurisdictions within a federation may compete in the provision of public goods in order to attract some residents (Tiebout, 1956) and expel others (Brueckner, 1999); and/or for business. We address the vast literature on welfare gains or losses of these types of competition. Then, we discuss the empirical evidence, focusing on estimates of the sensitiveness of production factors to tax differentials and on the importance of the strategic interdependence among jurisdictions. We combine econometric studies with some case studies. Last we discuss the design of mechanisms to cope with fiscal competition, especially under a more global environment where factors become more mobile.

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This thesis is the Logistics Development Forum's assignment and the work dealing with the development of the Port of Helsinki as part of Helsinki hub. The Forum aims to develop logistics efficiency through public-private co-operation and development of the port is clearly dependent on both factors. Freight volumes in the Port of Helsinki are the biggest single factor in hub and, therefore, the role of the port of the entire hub development is strong. The aim is to look at how the port will develop as a result of changes in the foreign trade of Finland and the Northern European logistics trends in 25 years time period. Work includes the current state analysis and scenario work. The analyses are intended to find out, which trends are the most important in the port volume development. The change and effect of trends is examined through scenarios based on current state. Based on the work, the structure of Finnish export industry and international demand are in the key role in the port volume development. There is significant difference between demands of Finnish exporting products in different export markets and the development between the markets has different impacts on the port volumes by mass and cargo type. On the other hand, the Finnish economy is stuck in a prolonged recession and competition between ports has become a significant factor in the individual port's volume development. Ecological valuesand regulations have changed the competitive landscape and maritime transport emissions reductions has become an important competitive factor for short routes in the Baltic Sea, such as in the link between Helsinki and Tallinn.

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Under EU competition law, parent companies may be held jointly and severally liable for the competition law infringements committed by their subsidiaries. The possibility of holding parent companies liable demonstrates a significant exception from the idea of separate legal entities. However, it is not the only deviation developed under EU competition law. In cases, where the legal entity responsible for the anti-competitive conduct has changed its form, liability can be attributed to the new operator, in particular, to its successor. The principles of legal certainty and legitimate expectations are issues that surround the doctrines of parental and successor liability. The aim of this thesis is to present a comprehensive comparative analysis of the parental and successor liability doctrines and to clarify the conditions under which it is possible to attribute liability for the infringements of EU competition law. The main purpose is therefore to demonstrate the problems related to the allocation of liability and to discuss whether these liability principles, established to assure the effective enforcement of the EU competition rules, are good solutions. The research methods used in this thesis are the legal dogmatic approach and the comparative law approach. The former enables the possibility of using the case law and legislation as a framework in which the difficulties concerning the application of parental and successor liability can be discussed while the latter ensures the comparison of the characteristics and judgments. The doctrines of parental and successor liability are both well established, but the application practice has caused several difficulties. These problems derive from, inter alia, the broadness and disjointed developed of the doctrines. There has been much recent case law dealing with these issues and having the potential to open up a considerable risk and to allocate strict liability for parent and successor companies.

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Our surrounding landscape is in a constantly dynamic state, but recently the rate of changes and their effects on the environment have considerably increased. In terms of the impact on nature, this development has not been entirely positive, but has rather caused a decline in valuable species, habitats, and general biodiversity. Regardless of recognizing the problem and its high importance, plans and actions of how to stop the detrimental development are largely lacking. This partly originates from a lack of genuine will, but is also due to difficulties in detecting many valuable landscape components and their consequent neglect. To support knowledge extraction, various digital environmental data sources may be of substantial help, but only if all the relevant background factors are known and the data is processed in a suitable way. This dissertation concentrates on detecting ecologically valuable landscape components by using geospatial data sources, and applies this knowledge to support spatial planning and management activities. In other words, the focus is on observing regionally valuable species, habitats, and biotopes with GIS and remote sensing data, using suitable methods for their analysis. Primary emphasis is given to the hemiboreal vegetation zone and the drastic decline in its semi-natural grasslands, which were created by a long trajectory of traditional grazing and management activities. However, the applied perspective is largely methodological, and allows for the application of the obtained results in various contexts. Models based on statistical dependencies and correlations of multiple variables, which are able to extract desired properties from a large mass of initial data, are emphasized in the dissertation. In addition, the papers included combine several data sets from different sources and dates together, with the aim of detecting a wider range of environmental characteristics, as well as pointing out their temporal dynamics. The results of the dissertation emphasise the multidimensionality and dynamics of landscapes, which need to be understood in order to be able to recognise their ecologically valuable components. This not only requires knowledge about the emergence of these components and an understanding of the used data, but also the need to focus the observations on minute details that are able to indicate the existence of fragmented and partly overlapping landscape targets. In addition, this pinpoints the fact that most of the existing classifications are too generalised as such to provide all the required details, but they can be utilized at various steps along a longer processing chain. The dissertation also emphases the importance of landscape history as an important factor, which both creates and preserves ecological values, and which sets an essential standpoint for understanding the present landscape characteristics. The obtained results are significant both in terms of preserving semi-natural grasslands, as well as general methodological development, giving support to science-based framework in order to evaluate ecological values and guide spatial planning.

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Correspondence from 1978 between Terry O'Malley and Gary Reinblatt, Assistant Vice-President, McDonald's Restaurants of Canada Ltd. regarding McDonald's account.

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Correspondence from 1978 between Terry O'Malley and Gary Reinblatt, Assistant Vice-President, McDonald's Restaurants of Canada Ltd. regarding McDonald's account.

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This ecological investigation of the beaver (Castor canadensis canadensis Kuhl) was part of the Eastern Slopes (Alberta) Watershed Research program conducted during the summers of 1968 . 1969 . 1970. and 1971 . A soil particle size analysis indicated that soil heavy with clay was used by the beaver for construction purposes in the Porcupine Hills . Examples were given of the beaver controlling erosion with the construction of dams . and also causing erosion to occur . However . in general . the beaver slow down soil erosion and decrease the loss of soil from this region. The beaver utilized measureable amounts of herbaceous vegetation . However, the utilization of herbs by the beaver requires further investigation. A system of ex~sures and enclosures of herbaceous vegetation plots was used to study the utilization of sedges , grasses , and forbs . The beaver indicated stronger species preference for willow as compared to aspen . The size preference for willow was in the 1.0 to 10.0 centimeters basal diameter classes , while the beaver utilization of aspen indicated a preference for the largest trees with basal diameter greater than 20.0 centimeters. Willow was the most important plant in the low lying areas with regard to distribution, abundance and to produce sustained yield. The beaver used this plant for food and construction throughout the study area. The distribution of aspen was limited. and this species did not appear to produce more than one crop in the lifetime of a beaver colony. Nine out of 15 woody plant types were sampled by the beaver in this region. A plot-intercept transect technique was used for systematic vegetation sampling of the woody vegetation in six intensively studied watersheds. The beaver population of the Porcupine Hills region of SW-Alberta is believed to depend upon the chinooks. During the 1971 ground census, a total of 60 active beaver colonies were tallied on the 930 square kilometers large study area. The beaver of the region were not found to store large food caches during fall and winter, however, they are believed to collect feed periodically throughout the winter months. It was observed that the severe winter in 1968-69, reduced by 27 per cent the number of active beaver colonies within the study area. The Porcupine Hills region had 0.07 beaver colony per square kilometer in 1971, a low density of beaver colonies due to the rough topography of the area. However, the importance of the beaver ponds was somewhat clarified as they provide increased moisture, which lessens the fire damage, and store water for wildlife and cattle in the area. Meteorological data was collected by the author in collaboration with the Department of Transport.

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During 1982 and 1983 I studied male attributes and attributes of the territory of male Eastern Meadowlarks (Sturnella magna) in order to determine whether there was a correlation between any of the attributes investigated and the number of females attracted by a male. Seventeen males, nine of which were polygynous and eight monogamous, were studied in 1982 and sixteen males.of which .. seven were polygynous and nine ~onogamous, were studied in 1983. The study was conducted in Short Hills Park, 10 km southwest of St. Catharines, Ontario and was designed to compare two hypotheses: the "sexy son" hypothesis (Weatherhead and Robertson,1977) and the polygyny threshold model (Verner and Willson,1966, Orians, 1969). Male attributes investigated were male size and song behaviour. Six measures of male size were taken: weight, flattened and natural wing chord length, culmen length, bill depth and length of the tarsometatarsus. In 1983 song repertoire size and song versatility measures were investigated. Attributes of the territory studied were: territory size, density of plant stems, percentage plant cover and measures of vegetation structure. In 1983 Arthropods were collected from each territory and sorted according to taxonomic group and size. During 1983, territory attributes were sampled twice, once early and once later in the nesting season. Analysis of data involved univariate comparisons between monogamous and polygynous males using T-tests and multivariate comparisons were made using discriminant function analysis (DFA) and principle components analysis (PCA).No correlations were found between the number of females attracted with, .ny measure of male size or with me, .sures of song versatili or size of song repertoire. Also no correlation was found between terri size and the number of females nesting on a terri . Some attributes of the male's terri id distinguish between monog,mous and po s males of thistudy. Analysis of Arthropod numbers showed that e~ .eran counts were significantly great~r on polygynous territories, a1 the total numb~rs of Arthropods collected showed no s fico .nt differences between territories of monogamous and po males. DFA chose ear teran and Hymenopteran counts as multivariate discriminators; both variables we' e more vegetation revealed that there were no univariate differences between the two groups of males fOT 1982 stem densities, but ~ spp. and Solidago spp. were chosen DFA as multivariate discriminators. The total number of plant stems and of Vicia spp. stems were s ficantly the early 1983 ing on monogamous territories for however DFA found no multivariate discriminators" Variables concerned with the overall aspects of vegetation structure showed significant differences between territories of monogamous and polygynous males. DFA of the 1982 sampling of vegetation structure showed significantly greater mat depth and vegetation height on polygynous territories, a finding which was not supported, however, by peA. For the early 1983 sampling period, plant height was greater on polygynous territories. Multivariate analysis identified greater green cover on polygynous territories, greater ground cover on monogamous territories, and greater depth of mat material on monogamous territories as discriminators between territories of monogamous and polygynous males. A DFA on the major variables of the study showed no significant difference between the territories of monogamous and polygynous male Meadowlarks. Of the correlations found, some were for non-prey Arthr~ods, for cover plants with very small samples sizes, or for variables which were greater for monogamous males during one sampling period and polygynous males during the next. While multivariate discriminators were found, peA showed no grouping of monogamous or polygynous males according to any of the variables investigated. On the basis of the univariate and multivariate analysis of major variables, I concluded that there were no correlations between the number of females attracted with male attributes and no unambiguous correlation with attributes of the territory. My study does not unequivocally support either the "sexy son" or the polygyny threshold hypothesis.

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The present study was carried out to test the hypothesis that photosynthetic bacteria contribute a large portion of the food of filter feeding zooplankton populations in Crawford Lake, Ontario. The temporal and spatial variations of both groups of organisms are strongly dependent on one another. 14 By using C-Iabelled photosynthetic bacteria. the ingestion and clearance rates of Daphnia pulex, ~. rosea, and Keratella spp were estimated during summer and fall of 1982. These quantitative estimations of zooplankton ingestion and clearence rates on photosynthetic bacteria comprised an original addition to the literature. Photosynthetic bacteria comprised a substantial portion of the diet of all four dominant zooplankton species. The evidence for this is based on the ingestion and clearance rates of the dominant zooplankton species. Ingestion rates of D. pulex and D. rosea ranged 5 5 -1 -1 - -- 5 - -- 5 from 8.3X10 -1 to 14.6XlO -1 cells.ind. hr and 8.1X10 to 13.9X10 cells.ind. hr • Their clearance rates ranged from 0.400 to 1.000 -1 -1 -1 -1 ml.ind. hr. and 0.380 to 0.930 ml.ind. hr • The ingestion and clearance -1 -1 -1 -1 rates of Keratella spp were 600 cell.ind. hr and 0.40 ul.ind. hr respectively. Clearance rates were inversely proportional to the concentration of food cells and directly proportional to the body size of the animals. It is believed that despite the very short reg~neration times of photosynthetic bacteria (3-8 hours) their population densities were controlled in part by the feeding rates of the dominant zooplankton in Crawford Lake. By considering the regeneration times of photosynthetic bacteria and the population clearance rates of zooplankton, it was estimated that between 16 to 52% and 11 to 35% of the PHotosynthetic bacteria were' consumed· by Daphnia· pulex. and Q.. rosea per day. The temporal and spatial distribution of Daphnia pulex, !.. rosea, Keratella quadrata, K. coChlearis and photosynthetic bacteria in Crawford Lake were also investigated during the period of October, 1981 to December, 1982. The photosynthetic bacteria in the lake, constituted a major food source for only those zooplankton Which tolerate anaerobic conditions. Changes in temperature and food appeared to correlate with the seasonal changes in zooplankton density. All four dominant species of zooplankton were abundant at the lake's surface (O-4m) during winter and spring and moved downwards with the thermocline as summer stratification proceeded. Photosynthetic bacteria formed a 2 m thick layer at the chemocline. The position of this photosynthetic bacterial J-ayer changed seasonally. In the summer, the bacterial plate moved upwards and following fall mixing it moved downwards. A vertical shift of O.8m (14.5 to 15.3m) was recorded during the period of June to December. The upper limit of the photosynthetic bacteria in the water column was controlled by dissolved oxygen, and sulfide concentrations While their lower limit was controlled by light intensity. A maximum bacterio- 1 chlorophyll concentration of 81 mg Bchl.l was recorded on August 9, 1981. The seasonal distribution of photosynthetic bacteria was controlledinpart' by ·theg.-"z1ai'_.Q;~.zoopl. ank:tCm;-.Qther -ciactors associated with zooplankton grazing were oxygen and sulfide concentrations.