932 resultados para Most Productive Scale Size
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Effects of grazing intensity on leaf photosynthetic rate (Pn), specific leaf area (SLA), individual tiller density, sward leaf area index (LAI), harvested herbage DM, and species composition in grass mixtures (Clinelymus nutans + Bromus inermis, Elymus nutans + Bromus inermis + Agropyron cristatum and Elymus nutans + Clinelymus nutans + Bromus inermis + Agropyron cristatum) were studied in the alpine region of the Tibetan Plateau. Four grazing intensities (GI), expressed as feed utilisation rates (UR) by Tibetan lambs were imposed as follows: (1) no grazing; (2) 30% UR as light grazing; (3) 50% UR as medium grazing; and (4) 70% UR as high grazing. Leaf Pn rate and tiller density of grasses increased (P < 0.05), while sward LAI and harvested herbage DM declined (P < 0.05) with the increments of GI, although no effect of GI on SLA was observed. With increasing GI, Elymus nutans and Clinelymus nutans increased but Bromus inermis and Agropyron cristatum decreased in swards, LAI and DM contribution. Whether being grazed or not, Elymus nutans + Clinelymus nutans + Bromus inermis + Agropyron cristatum was the most productive sward among the grass mixtures. Thus, two well-performed grass species (Elymus nutans and Clinelymus nutans) and the most productive mixture of four species should be investigated further as the new feed resources in the alpine grazing system of the Tibetan Plateau. Light grazing intensity of 30% UR was recommended for these grass mixtures when swards, LAI, herbage DM harvested, and species compatibility were taken into account.
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Gaochentou region is located in the southwest direction of Gaochentou village in Huanghua city of Hebei province. In regionally structural position, It lies in Qikou sag In the middle part of Huanghua depression, which belongs to the east part of the south Dagang structure zone in the middle part of Huanghua depression. Its' very beneficial at regional structure in Gaochentou , and It becomes the advantage area for oil and gas gathered and preserved, Sandstone reservoir of Dongying Formation is main bearing bed .Dongying Formation in Gaochentou region of Huanghua depression is consisted of set of mudstone and sandstone interbeds by deposited delta fades . Dongying Formation can be divided into 3 members from above to below: the first member of Dongying Formation (FMDF), the second member of Dongying Formation (SMDF), and third member of Dongying Formation (TMDF). The lithology of the upper part of FMDF was consisted of mostly middle-grained and fine-grained sandstone, and it is small for the oil-bearing area of the sand bodies .The lithology of the lower part is coarse-grained sandstone bodies which are well connected between sandstone bodies of wells, and the lower part was main bed of oil production in Dongying Formation; SMDF and TMDF are consisted of larger scale set of mudstone, in which the sandbodies are lenticular and pinch out quickly, and the lithology was mostly fine sandstone and silt stone, in which there are little oil and gas .Because the reservoirs in this area are largely influenced by the factors such as lithology, fault and others, and the reservoirs have the strong,heterogeneity , there exists the problem of oil-down and water-up for vertical distribution of oil and gas bearing. It is not very clearly for the three dimension distribution of sandstone , and the geology researchs is not enough. So, it can't satisfy the need of further development and production for Gaochentou oilfield.Having the key problem of oil-down and water-up and the mechanism of the reservoir for Gaochentou area, There are as follow study works, the first, is study of the high-resolution correlation of sequence stratigraphy and sedimentary microfacies. Dongying Formation was divided into three parasequence sets and each parasequence set was divided into different amount of parasequences. FMDF, as the main oil and gas producing bed, can be divided into seven parasequences. Oil and gas are discovered in six parasequences except the seventh. On the basis of study of sedimentary microfacies, the sediments of Dongying Formation are considered deposited mainly in delta front subfacies. The microfacies types of Dongying Formation are sub-water distirbutary channel, sub-water natural bank, inter distributary channel bay, distributary channel mouth dam, and delta front mat sand.Seismic facies analysis and logging-constrained inversion technique were applied by Author for transverse prediction of sandstone reservoir. Having 4 modes of interwell single sandbodies correlation technique, Author have described distribution characteristics of sandbodies, and established geological reservoir model of Gaochentou reservoir.Author presented that the reservoirs characteristic have very strong heterogeneity ,and In the section of sandstone interlayed with mudstone,the folium sandstone interlayed with each other, and the wedge shaped sandbodies pinched out in the mudstone. So the pinch-out up sandstone trap and lenticular sandstone trap are easily formed. They are most small scale overlying pinches out in the place of slope. This article applies the concept of deep basin oil to resolve reasonably the problem of which the oil is below the water in Gaochentou area. Combined with the study of sedimentary facies, reservoir and other aspects, the mechanism and patterns of deep basin oil are studied on the basis of characteristics in Gaochentou area.On the basis of the above study, the mechanism of the oil and gas' migration and accumulation in isotropic sandstone and heterogeneous sandstone are thoroughly analyzed through experiments on physical modeling. Experiments on physical modeling show that the discrepancy between sand layers with different permeability and thickness has important influence on the direction, path, and injection layer of oil's migration. At the beginning of the injection of oil and gas in high permeability sand layer, the pressure is low, the migration resistance is small, and the oil and gas are more easily displacing the water in sand. So it can act as good transformation layer or reservoir. But at the beginning of the injection of oil and gas in sand layer with low permeability, the pressure is high, the migration resistance is big, and the oil and gas are more difficultly displacing the water in sand. So it can only act as bad or worse transformation layer or reservoir. Even if it cannot act as transformation layer or reservoir, it can act as water layer or dry layer. The discrepancy between sand layers on permeability and thickness can make discrepancy in injection of oil and gas between different layers. Consequently it leads to small amount of oil and gas injection in sand layers with low permeability. Ultimately it affects the oil's accumulation and distribution in different sand layers.At Last, combining analysis of the structure and pool forming condition, The thesis has established models of reservoir formation to predict the advantage distribution of oil and gas bearing , and put forward the prospective target It is not only of theoretical signification for explosion and importance, but also has realistic value in guiding the progressive petroleum exploration and exploitation.
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RESUMO: O presente trabalho teve como objetivo avaliar genótipos de girassol semeados em segunda safra no ano de 2014 em Campo Novo do Parecis ? MT, no campo experimental do Instituto Federal de Educação Ciência e Tecnologia de Mato Grosso. O delineamento experimental utilizado foi o de blocos casualizados, com 16 tratamentos (16 genótipos) e quatro repetições. As parcelas experimentais foram constituídas de 4 linhas com 6,5 m de comprimento, com espaçamento entrelinhas de 0,45 m, contendo área de 11,7 m², totalizando uma área de 748m². Foi utilizada a população de 45000 plantas por hectare. Os dados foram submetidos à análise de variância e ao teste Scott-Knott, a 5% de probabilidade. Para a massa de mil aquênios, os genótipos que se destacaram foram BRS 323, MG 360 e M734 enquanto que as os mais produtivos foram os genótipos MG 360, AGUARÁ 06, MG 305, AGUARÁ 04, CF 101, SYN 045, GNZ NEON, HELIO 251 e SYN 3950HO. ABSTRACT: This study aimed to evaluate genotypes of sunflower seeded second harvest in the year 2014 in Campus Campo Novo do Parecis, in the experimental field of the Instituto Federal de Educação Ciência e Tecnologia de Mato Grosso. The experimental design was a randomized block design with treatments 16 (16 genotypes) and four replications. The experimental plots consisted of four rows 6.5 m long with row spacing of 0.45 m, containing area of 11.7 m², totaling an area of 748 m². The population of 45000 plants per hectare is used. Data were subjected to analysis of variance and the Scott - Knott test at 5 % probability. For the mass of thousand achenes, genotypes that stood out were BRS 323, MG 360 and M734 while the most productive genotypes were the MG 360, AGUARÁ 06, MG 305, AGUARÁ 04, CF 101, SYN 045, GNZ NEON, HELIO 251 and SYN 3950HO.
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McInnes, C., 'HIV/AIDS and national security', in: AIDS and Governance, N. Poku, A. Whiteside and B. Sandkjaer (eds.),(Aldershot: Ashgate, 2007), pp.93-111 RAE2008
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Unlike some other major composer-pianists (Franz Liszt and Alexander Scriabin being the most notable examples), Sergei Rachmaninov did not experience any dramatic changes in his compositional style; one can, however, notice certain stylistic differences between piano works composed during different periods of his long creative life. This dissertation argues that a clear evolution of Rachmaninov's pianistic style through his three creative periods can be traced by examining a selection of his compositions, from his first significant cycle for piano, 5 Marceaux de fantaisie, Op. 3 (1892), all the way through to his last piano work, a transcription of P.I.Tchakovsky's Lullaby, Op. 16, No. 1 (1941). Rachmaninov's life as a composer can be divided into three periods. His early period was ended abruptly by the disastrous premiere ofhis First Symphony in 1897, which caused a deep psychological crisis in the life of the young composer. Piano works of this period are often characterized by relatively simple homophonic texture, when Rachmaninov was clearly influenced by some of his Russian predecessors, most notably Tchaikovsky. His second and most productive period, also known as the period of"Russian maturity," started in 1900, when he began working on the Second Suite for two pianos, Op. 17, and the Second Concerto, Op. 18; this phase ended with the Russian Bolshevik revolution of 1917. Works of this time exhibit a mature style of piano writing, with rich, virtuosic - often considered excessive by many critics - texture and ever-increasing use of chromatic harmonies. Rachmaninov's works of the third period are limited in number owing to the composer's preoccupation with a career as pianist. Original works for piano now give way to revisions of earlier compositions and transcriptions: Rachmaninov's piano writing becomes more efficient and economical without losing any of its virtuosic brilliance. This dissertation project examines in detail, over the course of three piano recitals, a variety of works composed during the "Russian maturity" period, from several Preludes from Op. 23 (1903), the first major cycle for solo piano of the period, to 9 Etudes-Tableaux, Op.39 (1917), the last one; the early period is represented by 3 of 5 Marceaux defantaisie, Op. 3 (1892), while the late period is shown through several piano transcriptions and revised versions of the remaining 2 pieces from Op. 3.
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Cognitive neuroscience, as a discipline, links the biological systems studied by neuroscience to the processing constructs studied by psychology. By mapping these relations throughout the literature of cognitive neuroscience, we visualize the semantic structure of the discipline and point to directions for future research that will advance its integrative goal. For this purpose, network text analyses were applied to an exhaustive corpus of abstracts collected from five major journals over a 30-month period, including every study that used fMRI to investigate psychological processes. From this, we generate network maps that illustrate the relationships among psychological and anatomical terms, along with centrality statistics that guide inferences about network structure. Three terms--prefrontal cortex, amygdala, and anterior cingulate cortex--dominate the network structure with their high frequency in the literature and the density of their connections with other neuroanatomical terms. From network statistics, we identify terms that are understudied compared with their importance in the network (e.g., insula and thalamus), are underspecified in the language of the discipline (e.g., terms associated with executive function), or are imperfectly integrated with other concepts (e.g., subdisciplines like decision neuroscience that are disconnected from the main network). Taking these results as the basis for prescriptive recommendations, we conclude that semantic analyses provide useful guidance for cognitive neuroscience as a discipline, both by illustrating systematic biases in the conduct and presentation of research and by identifying directions that may be most productive for future research.
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The North Sea is a dynamic large marine ecosystem which is bordered by a dense coastal population, contains a productive oil and gas province, has a dense shipping network and has one of the most productive fisheries in the world. An assessment of the state of health of the North Sea was initiated in 1987 as part of a developing series of international initiatives at Ministerial level to address concerns over the impact of these activities on the marine ecosystem. Four North Sea Ministerial Conferences (1984, 1987, 1990, 1995) and an Intermediate Ministerial Meeting (1993) have been held to date to develop a harmonized approach to the sustainable management of the North Sea. In 1988 at the request of Ministers a North Sea Task Force was established to co-ordinate work leading to the production of a Quality Status Report (QSR) on the North Sea in December 1993. In recognition of the large geographical and ecological diversity exhibited, a sub-regional approach was adopted and a total of 13 sub-regional assessment reports were produced to a common protocol. The Task Force established a five-year plan to co-ordinate research, monitoring and modelling and other special topics in the preparations for the QSR. As part of this exercise a ‘Monitoring Master Plan’ was drawn up to provide for the first time reliable spatial information on the distribution of chemical contaminants and biological effects throughout the North Sea. The Task Force was a unique structure in international collaboration with a fixed remit that ended in December 1993. It was successful in bringing together many diverse organisations with interests in the North Sea and co-ordinated to a tight timetable the production of the QSR. The experiences gained are now being applied to the whole north east Atlantic under a new OSPAR Convention and have wide application to other Large Marine Ecosystems.
Variation of phytoplankton assemblages along the Mozambique coast as revealed by HPLC and microscopy
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This study is an integrated overview of pigment and microscopic analysis of phytoplankton communities throughout the Mozambican coast. Collected samples revealed notable patterns of phytoplankton occurrence and distribution, with community structure changing between regions and sample depth. Pigment data showed Delagoa Bight, Sofala Bank and Angoche as the most productive regions throughout the sampled area. In general, micro-sized phytoplankton, particularly diatoms, were important contributors to biomass both at surface and sub-surface maximum (SSM) samples, although were almost absent in the northern stations. In contrast, nano- and pico-sized phytoplankton revealed opposing patterns. Picophytoplankton were most abundant at surface, as opposed to nanophytoplankton, which were more abundant at the SSM. Microphytoplankton were associated with cooler southern water masses, while picophytoplankton were related to warmer northern water masses. Nanophytoplankton were found to increase their contribution to biomass with increasing SSM. Microscopy information on the genera and species level revealed the diatoms Chaetoceros spp., Proboscia alata, Pseudo-nitzschia spp., Cylindrotheca closterium and Hemiaulus haukii as the most abundant taxa of the micro-sized phytoplankton. Discosphaera tubifera and Emiliania huxleyi were the most abundant coccolithophores, nano-sized phytoplankton.
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Some commercial fish species of the northeast Atlantic Ocean have relocated in response to warming. The impact of warming on marine assemblages in the region may already be much greater than appreciated, however, with over 70% of common demersal fish species responding through changes in abundance, rather than range. The northeast Atlantic Ocean is one of the most productive marine ecoregions in the world with a substantial commercial fishery. It is also a region that has undergone particularly rapid warming over the past 50 years, up to four times faster than the global average1. Compared with other marine regions worldwide, the biological response in the northeast Atlantic Ocean has been particularly dramatic, reflecting this rapid warming. Studies have documented biogeographical movements in marine plankton of over 1,000 km northwards2 and advances in the onset of key life-history events by six to eight weeks3. In addition, there has been limited evidence of distributional shifts in some fish species along latitudinal and depth gradients in response to warming4, 5. Writing in Current Biology, Stephen Simpson and colleagues6 present the most comprehensive analysis so far of the impact of warming on commercially important European continental-shelf fish species in the region, and in doing so show that there has been a profound reorganization of local communities.
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Permeable reactive barriers are a technology that is one decade old, with most full-scale applications based on abiotic mechanisms. Though there is extensive literature on engineered bioreactors, natural biodegradation potential, and in situ remediation, it is only recently that engineered passive bioreactive barrier technology is being considered at the commercial scale to manage contaminated soil and groundwater risks. Recent full-scale studies are providing the scientific confidence in our understanding of coupled microbial (and genetic), hydrogeologic, and geochemical processes in this approach and have highlighted the need to further integrate engineering and science tools.
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The analysis of chironomid taxa and environmental datasets from 46 New Zealand lakes identified temperature (February mean air temperature) and lake production (chlorophyll a (Chl a)) as the main drivers of chironomid distribution. Temperature was the strongest driver of chironomid distribution and consequently produced the most robust inference models. We present two possible temperature transfer functions from this dataset. The most robust model (weighted averaging-partial least squares (WA-PLS), n = 36) was based on a dataset with the most productive (Chl a > 10 lg l)1) lakes removed. This model produced a coefficient of determination (r2 jack) of 0.77, and a root mean squared error of prediction (RMSEPjack) of 1.31C. The Chl a transfer function (partial least squares (PLS), n = 37) was far less reliable, with an r2 jack of 0.49 and an RMSEPjack of 0.46 Log10lg l)1. Both of these transfer functions could be improved by a revision of the taxonomy for the New Zealand chironomid taxa, particularly the genus Chironomus. The Chironomus morphotype was common in high altitude, cool, oligotrophic lakes and lowland, warm, eutrophic lakes. This could reflect the widespread distribution of one eurythermic species, or the collective distribution of a number of different Chironomus species with more limited tolerances. The Chl a transfer function could also be improved by inputting mean Chl a values into the inference model rather than the spot measurements that were available for this study.
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The theoretical concept of ‘social capital’ has been increasingly invoked in connection to religion by academics, policy makers, charities and Faith Based Organisations (FBOs). Drawing on the popularisation of the term by Robert Putnam, many in these groups have hailed the religious as one of the most productive generators of social capital in today’s societies. In this article, we examine this claim through ethnographic material relating to Faithworks, a national ‘movement’ of Christians who provide welfare services within their communities. We claim that to apply the term ‘social capital’ in a meaningful sociological manner to FBOs requires a return to Pierre Bourdieu’s use of the term in order to refuse to extricate it from the practices in which it is enmeshed.
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The number of well-dated pollen diagrams in Europe has increased considerably over the last 30 years and many of them have been submitted to the European Pollen Database (EPD). This allows for the construction of increasingly precise maps of Holocene vegetation change across the continent. Chronological information in the EPD has been expressed in uncalibrated radiocarbon years, and most chronologies to date are based on this time scale. Here we present new chronologies for most of the datasets stored in the EPD based on calibrated radiocarbon years. Age information associated with pollen diagrams is often derived from the pollen stratigraphy itself or from other sedimentological information. We reviewed these chronological tie points and assigned uncertainties to them. The steps taken to generate the new chronologies are described and the rationale for a new classification system for age uncertainties is introduced. The resulting chronologies are fit for most continental-scale questions. They may not provide the best age model for particular sites, but may be viewed as general purpose chronologies. Taxonomic particularities of the data stored in the EPD are explained. An example is given of how the database can be queried to select samples with appropriate age control as well as the suitable taxonomic level to answer a specific research question. © 2013 The Author(s).
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Tenure-track contract is criticized for curbing the incentives to expend effort after obtaining tenured status. Yet the most productive faculties seem to work on a tenure contract, and schools which aim to employ the best faculty seem to prefer to offer tenure-track contracts to their new recruits. I argue that tenure-track contracts are by construction more attractive to more able freshly minted PhDs, and therefore the observed sorting is rationalizable.
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A Masters Thesis, presented as part of the requirements for the award of a Research Masters Degree in Economics from NOVA – School of Business and Economics