894 resultados para limits to growth


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Fast pyrolysis liquid or bio-oil has been used in engines with limited success. It requires a pilot fuel and/or an additive for successful combustion and there are problems with materials and liquid properties. It is immiscible with all conventional hydrocarbon fuels. Biodiesel, a product of esterification of vegetable oil with an alcohol, is widely used as a renewable liquid fuel as an additive to diesel at up to 20%. There are however limits to its use in conventional engines due to poor low temperature performance and variability in quality from a variety of vegetable oil qualities and variety of esterification processes. Within the European Project Bioliquids-CHP - a joint project between the European Commission and Russia - a study was undertaken to develop small scale CHP units based on engines and microturbines fuelled with bioliquids from fast pyrolysis and methyl esters of vegetable oil. Blends of bio-oil and biodiesel were evaluated and tested to overcome some of the disadvantages of using either fuel by itself. An alcohol was used as the co-solvent in the form of ethanol, 1-butanol or 2-propanol. Visual inspection of the blend homogeneity after 48 h was used as an indicator of the product stability and the results were plotted in a three phase chart for each alcohol used. An accelerated stability test was performed on selected samples in order to predict its long term stability. We concluded that the type and quantity of alcohol is critical for the blend formation and stability. Using 1-butanol gave the widest selection of stable blends, followed by blends with 2-propanol and finally ethanol, thus 1-butanol blends accepted the largest proportion of bio-oil in the mixture. © 2013 Elsevier Ltd. All rights reserved.

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It is very well known that contrast detection thresholds improve with the size of a grating-type stimulus, but it is thought that the benefit of size is abolished for contrast discriminations well above threshold (e.g., Legge, G. E., & Foley, J. M. (1980)]. Here we challenge the generality of this view. We performed contrast detection and contrast discrimination for circular patches of sine wave grating as a function of stimulus size. We confirm that sensitivity improves with approximately the fourth-root of stimulus area at detection threshold (a log-log slope of -0.25) but find individual differences (IDs) for the suprathreshold discrimination task. For several observers, performance was largely unaffected by area, but for others performance first improved (by as much as a log-log slope of -0.5) and then reached a plateau. We replicated these different results several times on the same observers. All of these results were described in the context of a recent gain control model of area summation [Meese, T. S. (2004)], extended to accommodate the multiple stimulus sizes used here. In this model, (i) excitation increased with the fourth-root of stimulus area for all observers, and (ii) IDs in the discrimination data were described by IDs in the relation between suppression and area. This means that empirical summation in the contrast discrimination task can be attributed to growth in suppression with stimulus size that does not keep pace with the growth in excitation. © 2005 ARVO.

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The effects of haem limitation and iron restriction on cells of non typable Haemophilus influenzae were investigated. Haem limitation was achieved by adding concentrations of haem to growth media which resulted in substantial decreases in final cell yields. Iron restriction was achieved by substituting protoporphyrin IX (PPIX) for haem in the growth medium and adding an iron chelator to the system. The effect of these nutrient limitations on a) outer membrane composition, and b) respiratory systems of non typable H.influenzae was investigated. Several of the strains examined produced new PPIX-specific outer membrane proteins when cultured utilising PPIX as a porphyrin source. The immune response of patients with bronchiectasis to outer membrane antigens of H.influenzae cultured under iron-restricted conditions was analysed by ELISA and immunoblotting techniques. ELISA analysis revealed that individuals with severe bronchiectasis had high titres of antibodies directed against H.influenzae OMs in both serum and sputum. Immunoblotting with homologous serum showed that where PPIX-specific OMPs were produced they were antigenic and were recognised by patients' serum. This suggested that these H.influenzae OMPs may be expressed in vivo. Additionally, the development of the immune responses to non typable H.influenzae outer membrane antigens was investigated using a rat lung model. Bacteria encased in agar beads were inoculated intratracheally into rat lungs, infection was established, and the immune response monitored for 6 weeks. The animals developed antibodies to PPIX-specific OMPs during the course of infection, providing further evidence that H.influenzae express these novel OMP antigens when growing in vivo. Studies in vitro on respiratory systems of phenotypically altered H.influenzae showed that bacteria grown utilising PPIX as a porphyrin source, or under conditions of iron-restriction produced ten fold fewer cytochromes than cells grown in nutrient excess, while haem limited H.influenzae produced no detectable cytochromes. Respiration of various substrates was depressed in haem limited and in PPIX-grown cultures as compared with cells grown in nutrient excess.

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In this paper we explore the relationship between the individual decision to become an entrepreneur and the institutional context. We pinpoint the critical roles of property rights and the size of the state sector for entrepreneurial activity and test the relationships empirically by combining country-level institutional indicators for 44 countries with working age population survey data taken from the Global Enterprise Monitor. A methodological contribution is the use of factor analysis to reduce the statistical problems with the array of highly collinear institutional indicators. We find that the key institutional features that enhance entrepreneurial activity are indeed the rule of law and limits to the state sector. However, these results are sensitive to the level of development.

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Background: Tumour cells show greater dependency on glycolysis so providing a sufficient and rapid energy supply for fast growth. In many breast cancers, estrogen, progesterone and epidermal growth factor receptor-positive cells proliferate in response to growth factors and growth factor antagonists are a mainstay of treatment. However, triple negative breast cancer (TNBC) cells lack receptor expression, are frequently more aggressive and are resistant to growth factor inhibition. Downstream of growth factor receptors, signal transduction proceeds via phosphatidylinositol 3-kinase (PI3k), Akt and FOXO3a inhibition, the latter being partly responsible for coordinated increases in glycolysis and apoptosis resistance. FOXO3a may be an attractive therapeutic target for TNBC. Therefore we have undertaken a systematic review of FOXO3a as a target for breast cancer therapeutics. Methods: Articles from NCBI were retrieved systematically when reporting primary data about FOXO3a expression in breast cancer cells after cytotoxic drug treatment. Results: Increased FOXO3a expression is common following cytotoxic drug treatment and is associated with apoptosis and cell cycle arrest. There is some evidence that metabolic enzyme expression is also altered and that this effect is also elicited in TNBC cells. FOXO3a expression serves as a positive prognostic marker, especially in estrogen (ER) receptor positive cells. Discussion: FOXO3a is upregulated by a number of receptor-dependent and -independent anti-cancer drugs and associates with apoptosis. The identification of microRNA that regulate FOXO3a directly suggest that it offers a tangible therapeutic target that merits wider evaluation.

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The saxicolous lichen vegetation on Ordovician slate rock at the mouth of the River Dovey, South Merionethshire, Wales was described in relation to several environmental variables which include aspect, slope angle, light intensity, rock porosity, rock microtopography and rock stability. Each of the measured environmental variables was shown to influence the lichen vegetation. A number of groups of species which were characteristic of certain environments were described. The data from the saxicolous lichen communities were analysed using multivariate analysis. Qualitative and quantitative data were ordinated, the qualitative data being easier to interpret ecologically, and site number (which reflects distance from the sea and altitude), rock porosity and light intensity were shown to be important environmental variables. A classification of the data was also carried out. The results of the ordination and classification were combined together and a model constructed which describes saxicolous lichen vegetation. A method which uses the model as an aid to the design and interpretation of field experiments is described. The model is applied to an experiment which investigates the effect on growth of transplanting four saxicolous lichens to different aspects. Growth was inhibited in Physcia orbicularis and Parmelia conspersa on rock surfaces of northwest aspect compared with growth on rock surfaces of southeast aspect. Growth was inhibited in Parmelia glabratula ssp. fuliginosa on rock surfaces of southeast aspect compared with rock surfaces of northwesr aspect. The growth of Parmelia saxatilis was similar at both southeast and northwesr aspects. Growth inhibition or stimulation in thalli of Physcia orbicularis, Parmelia conspersa and Parmelia glabratula ssp. fuliginosa after transplantation was consistent with the predictions of the model while the results for Parmelia saxatilis were not as expected. There was evidence that the frequency of Parmelia conspersa and Parmelia glabratula at a site is related to an effect of the environment on the growth of the thalli. There was also evidence that the frequency of Physcia orbicularis at a site is related to an effect of the environment on the establishment phase of the thalli and for the competitive exclusion of Parmelia saxatilis thalli from southeast facing rock surfaces. The distribution of lichens in relation to height on nine rock surfaces was investigated. It was suggested that the distribution of the lichens was influenced by microclimatic factors which are related to height on the rock, environmental variables which are associated with the rock substratum (e.g. rock porosity and rock microtopography) and by historical factors. The pattern of one crustose and one foliose lichen on four rock surfaces of different aspect and slope was investigated. On the vertically inclined surface the density of small thalli of Buellia aethalea and Parmelia glabratula ssp fuliginosa was correlated with the microtopography of the surface in transects horizontally across the rock surface but not in transects vertically down the rock surface. there were consitent differences in the scale and intensity of pattern horizontally and vertically and also a decrease in the intensity of pattern vertically as the slope of the rock surface decreased. These results were consistent with the suggestion of a gradient of microclimatic factors up the rock. The differences in the scale and intensity of pattern in different size classes in the population were consistent with the changes in pattern with time which have been shown to occur during succession in sand dune and salt marsh vegetation. The relationship between thallus size and height on a rock surface and between the radial growth rate and location of a thallus on a rock surface were investigated. Thalli of Parmelia glabratula ssp. fuliginosa were larger at the top of the rock surface than at the bottom and the data were consistent with the suggestion that the colonisation of the rock surface began at the top and, in time, spread downwards. The radial growth rate of the thalli could not be related to variation in slope, porosity, microtopography or directly to height on the rock but could be related to the horizontal location of the thalli on the rock. These results were consistent with the suggestion that here is a gradient of microclimatic factors across the rock surface which is also modified by height on the rock surface. The succession of lichen communities was described by relating the vegetation to rock porosity, rock microtopography, species diversity and rock stability. An initial stage dominated by crustose lichens leads to communities dominated by crustose, foliose and fruticose species. In the late stages of the succession on some rock surfaces crustose species again become dominant. The occurrence of the climax state and cyclic vegetation change in lichen communities are discussed. A mthod of estimating the age structure of a lichen population by relating thallus size to growth rate is described. The sources of error in the method are discussed in some detail and several refinements suggested to increase the accuracy of the method. The population dynamics of Parmelia glabratula ssp. fuliginosa was investigated by applying life tables to the age structures of eight different populations. The data were consistent with a period of relatively constant recruitment of thalli into the populations. Mortality in lichen populations was divided into deaths which occur after fragmentation of the thallus and deaths which occur after catastrophic environmental events. THe data suggest that the rate of fragmenting death is dependent on the age of the thallus while the rate of catastrophic death is dependent on the number of thalli established in an age class. A comparison of the numbers of thalli in each age class in the eight populations suggested that population density is controlled firstly, by climate and secondly, by variables related to the local rock surface environment. The rate of fragmenting death is related to the diversity of the community and the influence of diversity together with environmental variables in fluctuating or cyclic changes in population number.

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Production of human mesenchymal stem cells for allogeneic cell therapies requires scalable, cost-effective manufacturing processes. Microcarriers enable the culture of anchorage-dependent cells in stirred-tank bioreactors. However, no robust, transferable methodology for microcarrier selection exists, with studies providing little or no reason explaining why a microcarrier was employed. We systematically evaluated 13 microcarriers for human bone marrow-derived MSC (hBM-MSCs) expansion from three donors to establish a reproducible and transferable methodology for microcarrier selection. Monolayer studies demonstrated input cell line variability with respect to growth kinetics and metabolite flux. HBM-MSC1 underwent more cumulative population doublings over three passages in comparison to hBM-MSC2 and hBM-MSC3. In 100 mL spinner flasks, agitated conditions were significantly better than static conditions, irrespective of donor, and relative microcarrier performance was identical where the same microcarriers outperformed others with respect to growth kinetics and metabolite flux. Relative growth kinetics between donor cells on the microcarriers were the same as the monolayer study. Plastic microcarriers were selected as the optimal microcarrier for hBM-MSC expansion. HBM-MSCs were successfully harvested and characterised, demonstrating hBM-MSC immunophenotype and differentiation capacity. This approach provides a systematic method for microcarrier selection, and the findings identify potentially significant bioprocessing implications for microcarrier-based allogeneic cell therapy manufacture. Large-scale production of human bone-marrow derived mesenchymal stem cells (hBM-MSCs) requires expansion on microcarriers in agitated systems. This study demonstrates the importance of microcarrier selection and presents a systematic methodology for selection of an optimal microcarrier. The study also highlights the impact of an agitated culture environment in comparison to a static system, resulting in a significantly higher hBM-MSC yield under agitated conditions.

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The endothelium produces and responds to reactive oxygen and nitrogen species (RONS), providing important redox regulation to the cardiovascular system in physiology and disease. In no other situation are RONS more critical than in the response to tissue ischemia. Here, tissue healing requires growth factor-mediated angiogenesis that is in part dependent on low levels of RONS, which paradoxically must overcome the damaging effects of high levels of RONS generated as a result of ischemia. While generation of endothelial cell RONS in hypoxia/reoxygenation is acknowledged, the mechanism for their role in angiogenesis is still poorly understood. During ischemia, the major low molecular weight thiol glutathione (GSH) reacts with RONS and protein cysteines, producing GSH-protein adducts. Recent data indicate that GSH adducts on certain proteins are essential to growth factor responses in endothelial cells. Genetic deletion of the enzyme glutaredoxin-1, which selectively removes GSH protein adducts, improves, while its overexpression impairs, revascularization of the ischemic hindlimb of mice. Ischemia-induced GSH adducts on specific cysteine residues of several proteins, including p65 NFkB and the sarcoplasmic reticulum calcium ATPase-2 (SERCA2), appear to promote ischemic angiogenesis. Identifying the specific proteins in the redox response to ischemia has provided therapeutic opportunities to improve clinical outcomes of ischemia.

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A pénzügy kutatócsoport a TÁMOP-4.2.1.B-09/1/KMR-2010-0005 azonosítójú projektjében igen szerteágazó elemzési munkát végzett. Rámutattunk, hogy a különböző szintű gazdasági szereplők megnövekedett tőkeáttétele egyértelműen a rendszerkockázat növekedéséhez vezet, hiszen nő az egyes szereplők csődjének valószínűsége. Ha a tőkeáttételt eltérő mértékben és ütemben korlátozzák az egyes szektorokban, országokban akkor a korlátozást később bevezető szereplők egyértelműen versenyelőnyhöz jutnak. Az egyes pénzügyi intézmények tőkeallokációját vizsgálva kimutattuk, hogy a különféle divíziók közt mindig lehetséges a működés fedezetésül szolgáló tőkét (kockázatot) úgy felosztani, hogy a megállapodás felmondás egyik érintettnek se álljon érdekében. Ezt azonban nem lehet minden szempontból igazságosan megtenni, így egyes üzletágak versenyhátrányba kerülhetnek, ha a konkurens piaci szereplők az adott tevékenységet kevésbé igazságtalanul terhelték meg. Kimutattunk, hogy az egyes nyugdíjpénztárak befektetési tevékenységének eredményességére nagy hatással van a magánnyugdíjpénztárak tevékenységének szabályozása. Ezek a jogszabályok a társadalom hosszú távú versenyképességére vannak hatással. Rámutattunk arra is, hogy a gazdasági válság előtt a hazai bankok sem voltak képesek ügyfeleik kockázatviselő képességét helyesen megítélni, ráadásul jutalékrendszerük nem is tette ebben érdekelté azokat. Számos vizsgálatunk foglalkozott a magyar vállalatok versenyképességének alakulásával is. Megvizsgáltuk a különféle adónemek, árfolyamkockázatok és finanszírozási politikák versenyképességet befolyásoló hatását. Külön kutatás vizsgálta a kamatlábak ingadozásának és az hitelekhez kapcsolódó eszközfedezet meglétének vállalati értékre gyakorolt hatásait. Rámutattunk a nemfizetés növekvő kockázatára, és áttekintettük a lehetséges és a ténylegesen alkalmazott kezelési stratégiákat is. Megvizsgáltuk azt is, hogy a tőzsdei cégek tulajdonosai miként használják ki az osztalékfizetéshez kapcsolódó adóoptimalizálási lehetőségeket. Gyakorlati piaci tapasztalataik alapján az adóelkerülő kereskedést a befektetők a részvények egy jelentős részénél végrehajtják. Külön kutatás foglakozott a szellemi tőke hazai vállalatoknál játszott szerepéről. Ez alapján a cégek a problémát 2009-ben lényegesen magasabb szakértelemmel kezelték, mint öt esztendővel korábban. Rámutattunk arra is, hogy a tulajdonosi háttér lényeges hatást gyakorolhat arra, ahogyan a cégek célrendszerüket felépítik, illetve ahogy az intellektuális javakra tekintenek. _____ The Finance research team has covered a wide range of research fields while taking part at project TÁMOP-4.2.1.B-09/1/KMR-2010-0005. It has been shown that the increasing financial gearing at the different economic actors clearly leads to growth in systematic risk as the probability of bankruptcy climbs upwards. Once the leverage is limited at different levels and at different points in time for the different sectors, countries introducing the limitations later gain clearly a competitive advantage. When investigating the leverage at financial institutions we found that the capital requirement of the operation can always be divided among divisions so that none of them would be better of with cancelling the cooperation. But this cannot be always done fairly from all point of view meaning some of the divisions may face a competitive disadvantage if competitors charge their similar division less unfairly. Research has also shown that the regulation of private pension funds has vital effect on the profitability of the investment activity of the funds. These laws and regulations do not only affect the funds themselves but also the competitiveness of the whole society. We have also fund that Hungarian banks were unable to estimate correctly the risk taking ability of their clients before the economic crisis. On the top of that the bank were not even interested in that due to their commission based income model. We also carried out several research on the competitiveness of the Hungarian firms. The effect of taxes, currency rate risks, and financing policies on competitiveness has been analysed in detail. A separate research project was dedicated to the effect of the interest rate volatility and asset collaterals linked to debts on the value of the firm. The increasing risk of non-payment has been underlined and we also reviewed the adequate management strategies potentially available and used in real life. We also investigated how the shareholders of listed companies use the tax optimising possibilities linked to dividend payments. Based on our findings on the Hungarian markets the owners perform the tax evading trades in case of the most shares. A separate research has been carried out on the role played by intellectual capital. After that the Hungarian companies dealt with the problem in 2009 with far higher proficiency than five years earlier. We also pointed out that the ownership structure has a considerable influence on how firms structure their aims and view their intangible assets.

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Jelen tanulmány a spanyol–latin-amerikai kapcsolatok elmúlt két évtizedbeli alakulásának vázlatát adja, rámutatva a legfőbb mérföldkövekre, fordulópontokra és kihívásokra. A spanyol–latin-amerikai viszony sajátossága, hogy többszintű rendszerbe ágyazódik: Spanyolország egyes latin-amerikai országokhoz fűződő bilaterális viszonya, az ibér-amerikai csúcstalálkozók rendszere, az Európai Unió és Latin-Amerika biregionális stratégiai szövetsége, illetve az Unió egyes latin-amerikai integrációs tömörülésekhez (pl. Mercosur, Andok Közösség, Közép-amerikai Közös Piac stb.) és országokhoz fűződő kapcsolatai adják a legfontosabb tengelyeket; ezekből bontható ki Spanyolország és Latin-Amerika kapcsolatrendszere. Vagyis a fentebb vázolt rendszer miatt – kiegészülve az említett szereplők Egyesült Államokhoz fűződő viszonyával – önmagukban nehezen értelmezhetőek Spanyolország és volt amerikai gyarmatainak kapcsolatai, mivel szervesen a biregionális, interregionális és bilaterális kapcsolatok egészébe ágyazódnak. _____ The paper surveys the main trends of Spanish Latin America policy from the early 1990s up to the present. As typical of international relations in the 21st century, Spanish–Latin American relations are complex and involve multiple actors. Apart from Spain, the European Union, Latin American states as well as continental subregions and regional country groups are autonomous actors in this system of relations, where the United States is an important external actor. During the last twenty years, Spanish governments have prioritized relations with Latin America, which have seen considerable advances. At the same time, the limits to enhancing Spanish–Latin American relations, constraining factors aff ecting political and economic cooperation also exist and must be taken into consideration during the analysis of the issue.

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In the article - Past, Present, and Future: The Food Service Industry and Its Changes - by Brother Herman E. Zaccarelli, International Director, Restaurant, Hotel and Institutional Management Institute at Purdue University, Brother Zaccarelli initially states: “Educators play an important role in the evolution of the food service industry. The author discusses that evolution and suggests how educators can be change agents along with management in that evolutionary progression.” The author goes on to wax philosophically, as well as speak generically about the food service industry; to why it offers fascinating and rewarding careers. Additionally, he writes about the influence educators have on students in this regard. “Educators can speak about how the food service industry has benefited them both personally and professionally,” says Brother Zaccarelli. “We get excited about alerting students to the many opportunities and, in fact, serve as “salespersons” for the industry to whoever (school administrators, legislators, and peers in the educational institution) will listen.” Brother Zaccarelli also speaks to growth and changes in food service, and even more importantly about the people and faces behind everything that food service, and hospitality in general comprise. The author will have you know, that people are what drive an educator. “What makes the food service industry so great? At the heart of this question's answer is people: the people whom it serves in institutional and commercial operations of all types; the people who work within it; the people who provide the goods, services, and equipment to it; the people who study it,” says Brother Zaccarelli. “All of these groups have, of course, a vested personal and/or professional interest in seeing our industry improve.” Another concept the author would like you to absorb, and it’s even more so true today than yesterday, is the prevalence of convergence and divergence within food service. For food service and beyond, it is the common denominators and differences that make the hospitality-food service industry so dynamic and vibrant. These are the winds of change presented to an educator who wants to have a positive impact on students. The author warns that the many elements involved in the food service industry conspire to erode quality of service in an industry that is also persistently expanding, and whose cornerstone principles are underpinned by service itself. “The three concerns addressed - quality, employees, and marketing - are intimately related,” Brother Zaccarelli says in stripping-down the industry to bare essentials. He defines and addresses the issues related to each with an eye toward how education can reconcile said issues.

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Integer programming, simulation, and rules of thumb have been integrated to develop a simulation-based heuristic for short-term assignment of fleet in the car rental industry. It generates a plan for car movements, and a set of booking limits to produce high revenue for a given planning horizon. Three different scenarios were used to validate the heuristic. The heuristic's mean revenue was significant higher than the historical ones, in all three scenarios. Time to run the heuristic for each experiment was within the time limits of three hours set for the decision making process even though it is not fully automated. These findings demonstrated that the heuristic provides better plans (plans that yield higher profit) for the dynamic allocation of fleet than the historical decision processes. Another contribution of this effort is the integration of IP and rules of thumb to search for better performance under stochastic conditions.

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Twenty-four manganese nodules from the surface of the sea floor and fifteen buried nodules were studied. With three exceptions, the nodules were collected from the area covered by Valdivia Cruise VA 04 some 1200 nautical miles southeast of Hawaii. Age determinations were made using the ionium method. In order to get a true reproduction of the activity distribution in the nodules, they were cut in half and placed for one month on nuclear emulsion plates to determine the alpha-activity of the ionium and its daughter products. Special methods of counting the alpha-tracks resolution to depth intervals of 0.125 mm. For the first time it was possible to resolve zones of rapid growth (impulse growth) with growth rates, s > 50 mm/106 yr and interruptions in growth. With few exceptions the average rate of growth of all nodules was surprisingly uniform at 4-9 mm/10 yr. No growth could be recognized radioactively in the buried nodules. One exceptional nodule has had recent impulse growth and, in the material formed, the ionium is not yet in equilibrium with its daughter products. Individual layers in one nodule from the Indian Ocean could be dated and an average time interval of t = 2600±400 yr was necessary to form one layer. The alternation between iron and manganese-rich parts of the nodules was made visible by colour differences resulting from special treatment of cut surfaces with HCl vapour. The zones of slow growth of one nodule are relatively enriched in iron. Earlier attempts to find paleomagnetic reversals in manganese nodules have been continued. Despite considerable improvement in areal resolution, reversals were not detected in the nodules studied. Comparisons of the surface structure, microstructure in section and the radiometric dating show that there are erosion surfaces and growth surfaces on the outer surfaces of the manganese nodules. The formation of cracks in the nodules was studied in particular. The model of age-dependent nodule shrinkage and cracking surprisingly indicates that the nodules break after exceeding a certain age and/or size. Consequently, the breaking apart of manganese nodules is a continuous process not of catastrophic or discontinuous origin. The microstructure of the nodules exhibits differences in the mechanism of accretion and accretion rate of material, shortly referred to as accretion form. Thus non-directional growth inside the nodules as well as a directional growth may be observed. Those nodules with large accretion forms have grown faster than smaller ones. Consequently, parallel layers indicate slow growth. The upper surfaces of the nodules, protruding into the bottom water appear to be more prone to growth disturbances than the lower surfaces, immersed in the sediment. Features of some nodules show, that as they develop, they neither turned nor rolled. Yet unknown is the mechanism that keeps the nodules at the surface during continuous sedimentation. All in all, the nodules remain the objects of their own distinctive problems. The hope of using them as a kind of history book still seems to be very remote.

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This dissertation deals with the constitutional limits on the exercise of patent rights and its effects on the oil, natural gas and biofuels. Held with the support of ANP / PETROBRAS, It seeks to show how the law will limit the exercise of industrial property, based on a reinterpretation of private law by the constitutional development perspective . Today it is a fact that Petrobras, a Brazilian joint venture, has the latest technology in various sectors of the oil industry, and is one of the highest investments in developing new technologies. The overall objective of this thesis is to establish the relationship between the public interest of the Petroleum Industry, Natural Gas and Biofuels and constitutional limits to the free exercise of patent rights, then confirm or refute our hypothesis that Article 71 on Industrial Property Law is contrary to the existing objectives in Article 3 of the Constitution of the Federative Republic of Brazil. The research aims to examine the relevant aspects of the legal nature attributed to IPGN constitutionally confronting the constitutional limits on the free exercise of patent rights, with the purpose to outline the state of the performance limits in the regulation of the economy, in particular the application of feasibility limitations on the right of property in favor of national interest on the strategic energy industry. The aim is to confront the fundamental rights to property and economic development, against the public interest, limiting these first. As to the objectives, the research will be theoretical and descriptive and harvest of industrial property, respect the possible impact of regulatory standards and limiting the right of ownership in the oil industry. To establish how the state will mitigate the intellectual property right, we discuss, at first, a definition of public interest from the general theory of state and sovereign character in order to establish a new concept of national interest and popular interest, which will in turn the definition of our concept of public interest. In the second phase, will be addressed the issue of industrial property rights and how to will be free exercise thereof, in the constitutional sphere, infra, and demonstrating the use of industrial property rights with examples of market and IPGN . After situating the industrial property rights in the constitution and national legislation, establish their relationship with the national and regional development, will be addressed in this chapter in particular the patent law, as most usual form of intellectual property protection in IPGN. Used a study highlighting the number of patents in the area of the analyzed industry, demonstrating with hard data the importance of a sector for industrial development. The relationship between the social function of intellectual property and the constitutional objective of development was characterized to demonstrate the strategic nature of oil to Brazil in the national and international scene, and put into question the hypothesis of the research which provides that even with large investments the lack of legal certainty in the sector turns out not to have a considerable volume of investment as it could.

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The Environmental Education is a plural and diversified knowledge field, composed by a group of social agents of specific State, government and civil society sectors, with different world views and theoretical matrices that exercised and influenced its genealogy and constitutive dynamic. The Environmental Education – while specific knowledge field – has been produced, systematized and diffused in Brazil in the last decades by official State organisms, through public policies, as well as by social movements of popular education, and constitutes a large and historical movement about the environmental question, that was worldwide projected in the 1960 decade (the environmentalist movement). Concerning the creation of public policies and specific programs to the Environmental Education, in the scope of the governmental initiative, the approval of the National Policy of Environmental Education, by means of the Law n. 9.795/99 – together with its regulatory decree, the Decree nº 4.281 – represents the consolidation of a inclusion process of the environmental dimension in the educational field. These normative acts, beyond charging the public power with the incumbency to define public policies that incorporate the environmental dimension and to promote the Environmental Education in all education levels, also charge the educational institution with the duty of promoting this component in an integrated and articulated way with the educational programs that such institutions develop. In this context, it is aimed to identify and analyze under the light of the dialectical and historical materialism, the practices and concepts developed under the Federal University of Rio Grande do Norte (UFRN), with regard to its institutional policy on Environmental Education, relating it to establishing the Pnea. The analysis by means specific legislation on the subject and institutional documents UFRN. The research showed that, in general, the National Environmental Education Policy has limits to its effectiveness given the absence of specific funding for this purpose and the little government involvement in that the Brazilian State assumes, by through effective policies, the material conditions of financing actions with respect to this field of education. The fragmented and disjointed way the analyzed actions are developed constitutes a limit to the challenge for the UFRN implement, consistently and objectively, an Environmental Education policy, which can be monitored and evaluated as an effective public policy, both landmarks major goal of own Pnea as the demands of development whose agenda a critical environmental perspective.