888 resultados para colony productivity


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Interest in cognitive pretest methods for evaluating survey questionnaires has been increasing for the last three decades. However, analysing the features of the scientific output in the field can be difficult due to its prevalence in public and private institutes whose main mission is not scientific research. The aim of this research is to characterize the current state of scientific output in the field by means of two bibliometric studies for the period from 1980 to 2007. Study 1 analysed documents obtained from the more commonly used bibliographic databases. Study 2 supplemented the body of documents from Study 1 with documents from non-indexed journals, conference papers, etc. Results show a constant growth in the number of publications. The wide dispersion of publication sources, together with the highlighted role of the public and private institutions as centres of production, can also be identified as relevant characteristics of the scientific output in this field.

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Borrow areas are created where soil is removed to provide needed fill material for highway and other construction projects. Where these areas are located beyond the highway right-of-way, they must be restored and returned to useful purposes. In Iowa, borrow areas are often developed on agricultural lands and therefore, it is necessary to return them to agricultural uses whenever possible. This research project was established to evaluate the changes in row crop productivity where borrow is removed for highway construction. Secondly, several reclamation techniques were selected to be applied to borrow area research sites and the response of crops to each treatment will be evaluated. All borrow area research sites were selected in 1977 from Iowa Department of Transportation construction plans. The Audubon and Buchanan County sites were completed in the fall of 1977 and May 1978, respectively. Both were used for research in 1978, 1979, and 1980. The two remaining sites in Hamilton and Lee Counties were completed in the fall of 1978 and research was conducted at these sites in 1979, 1980, and 1981. In this report, the 1981 results from the Hamilton and Lee County borrow sites will be presented. Secondly, a summary of the three years of research from each borrow area will be presented along with specific and general conclusions from the research project.

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Intraspecific variability in social organization is common, yet the underlying causes are rarely known. In the fire ant Solenopsis invicta, the existence of two divergent forms of social organization is under the control of a single Mendelian genomic element marked by two variants of an odorant-binding protein gene. Here we characterize the genomic region responsible for this important social polymorphism, and show that it is part of a pair of heteromorphic chromosomes that have many of the key properties of sex chromosomes. The two variants, hereafter referred to as the social B and social b (SB and Sb) chromosomes, are characterized by a large region of approximately 13 megabases (55% of the chromosome) in which recombination is completely suppressed between SB and Sb. Recombination seems to occur normally between the SB chromosomes but not between Sb chromosomes because Sb/Sb individuals are non-viable. Genomic comparisons revealed limited differentiation between SB and Sb, and the vast majority of the 616 genes identified in the non-recombining region are present in the two variants. The lack of recombination over more than half of the two heteromorphic social chromosomes can be explained by at least one large inversion of around 9 megabases, and this absence of recombination has led to the accumulation of deleterious mutations, including repetitive elements in the non-recombining region of Sb compared with the homologous region of SB. Importantly, most of the genes with demonstrated expression differences between individuals of the two social forms reside in the non-recombining region. These findings highlight how genomic rearrangements can maintain divergent adaptive social phenotypes involving many genes acting together by locally limiting recombination.

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Four field trials were conducted, from 1995 to 1997, with the objective of studying the response of four upland cultivars to foliar fungicide application in relation to panicle blast control, grain yield and sustainability. Differential disease control and yield response of cultivars to fungicide treatment were obtained. Losses in grain yield of cultivars IAC 202, Caiapó, Rio Paranaíba and Araguaia due to panicle blast were 44.8%, 27.4%, 24.4% and 18.2%, respectively. Two applications of tricyclazole or benomyl controlled panicle blast, as indicated by lower values of disease progress curve and relative panicle blast severity, and increased grain yield of the cultivar IAC 202. The losses in 100 panicle grain weight and grain yield were significantly reduced by 22.3% and 25.1% in IAC 202 and 23.6% and 20.5% in Caiapó, respectively, with two sprays of tricyclazole. Sustainable value index for yield was maximum with two applications of tricyclazole (0.59), followed by one application at booting (0.46) and at heading (0.40) in cultivar IAC 202. Results showed no yield response of the cultivars Rio Paranaíba and Araguaia to fungicide applications for panicle blast control.

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This paper investigates relationships between cooperation, R&D, innovation and productivity in Spanish firms. It uses a large sample of firm-level micro-data and applies an extended structural model that aims to explain the effects of cooperation on R&D investment, of R&D investment on output innovation, and of innovation on firms’ productivity levels. It also analyses the determinants of R&D cooperation. Firms’ technology level is taken into account in order to analyse the differences between high-tech and low-tech firms, both in the industrial and service sectors. The database used was the Technological Innovation Panel (PITEC) for the period 2004-2010. Empirical results show that firms which cooperate in innovative activities are more likely to invest in R&D in subsequent years. As expected, R&D investment has a positive impact on the probability of generating an innovation, in terms of both product and process, for manufacturing firms. Finally, innovation output has a positive impact on firms’ productivity, being greater in process innovations. Keywords: innovation sources; productivity; R&D Cooperation

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We study the effects of the adoption of new agricultural technologies on structural transformation. To guide empirical work, we present a simple model where the effect of agriculturalproductivity on industrial development depends on the factor bias of technical change. We testthe predictions of the model by studying the introduction of genetically engineered soybeanseeds in Brazil, which had heterogeneous effects on agricultural productivity across areas withdifferent soil and weather characteristics. We find that technical change in soy production wasstrongly labor saving and lead to industrial growth, as predicted by the model.

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Mass spectrometry (MS) is currently the most sensitive and selective analytical technique for routine peptide and protein structure analysis. Top-down proteomics is based on tandem mass spectrometry (MS/ MS) of intact proteins, where multiply charged precursor ions are fragmented in the gas phase, typically by electron transfer or electron capture dissociation, to yield sequence-specific fragment ions. This approach is primarily used for the study of protein isoforms, including localization of post-translational modifications and identification of splice variants. Bottom-up proteomics is utilized for routine high-throughput protein identification and quantitation from complex biological samples. The proteins are first enzymatically digested into small (usually less than ca. 3 kDa) peptides, these are identified by MS or MS/MS, usually employing collisional activation techniques. To overcome the limitations of these approaches while combining their benefits, middle-down proteomics has recently emerged. Here, the proteins are digested into long (3-15 kDa) peptides via restricted proteolysis followed by the MS/MS analysis of the obtained digest. With advancements of high-resolution MS and allied techniques, routine implementation of the middle-down approach has been made possible. Herein, we present the liquid chromatography (LC)-MS/MS-based experimental design of our middle-down proteomic workflow coupled with post-LC supercharging.

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Recent studies on coffee (Coffea arabica L.) cultivation in agroforestry systems in Southern Brazil have shown the potential of partial shading to improve management of this crop. The objective of this work was to evaluate microclimatic conditions and their effects on coffee production of plants shaded with pigeon pea (Cajanus cajan) in comparison to unshaded ones, from May 2001 to August 2002 in Londrina, State of Paraná, Brazil. The appraised microclimatic characteristics were: global radiation, photosynthetic and radiation balance; air, leaf and soil temperatures; and soil humidity. Shading caused significant reduction in incident global solar radiation, photosynthetically active radiation and net radiation, and attenuated maximum leaf, air and soil temperatures, during the day. Shade also reduced the rate of cooling of night air and leaf temperatures, especially during nights with radiative frost. Soil moisture at 0-10 cm depth was higher under shade. The shaded coffee plants produced larger cherries due to slower maturation, resulting in larger bean size. Nevertheless, plants under shade emitted less plagiotropic branches, with smaller number of nodes per branch, and fewer nodes with fruits, resulting in a large reduction in coffee production. These results show the need to find an optimal tree density and management that do not compromise coffee production and protect against extreme temperatures.

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Resum en anglès del projecte de recerca L'empresa xarxa a Catalunya. TIC, productivitat, competitivitat, salaris i beneficis a l'empresa catalana té com a objectiu principal constatar que la consolidació d'un nou model estratègic, organitzatiu i d'activitat empresarial, vinculat amb la inversió i l'ús de les TIC (o empresa xarxa), modifica substancialment els patrons de comportament dels resultats empresarials, en especial la productivitat, la competitivitat, les retribucions dels treballadors i el benefici. La contrastació empírica de les hipòtesis de treball l'hem feta per mitjà de les dades d'una enquesta a una mostra representativa de 2.038 empreses catalanes. Amb la perspectiva de l'impacte de la inversió i l'ús de les TIC no s'aprecia una relació directa entre els processos d'innovació digital i els resultats de l'activitat de l'empresa catalana. En aquest sentit, hem hagut de segmentar el teixit productiu català per a buscar les organitzacions en què el procés de coinnovació tecnològica digital i organitzativa és més present i en què la intensitat de l'ús del coneixement és un recurs molt freqüent per a poder copsar impactes rellevants en els principals resultats empresarials. Això és així perquè l'economia catalana, avui, presenta una estructura productiva dual.

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BACKGROUND: High-dose therapy with autologous stem cell support after standard dose induction is a promising approach for therapy of primary central nervous system lymphoma (PCNSL). High-dose methotrexate (HD-MTX) is a standard drug for induction of PCNSL; however, data about the capacity of HD-MTX plus granulocyte-colony-stimulating factor (G-CSF) to mobilize hemopoietic progenitors are lacking. STUDY DESIGN AND METHODS: This investigation describes the data from stem cell mobilization and apheresis procedures after one or two cycles of HD-MTX for induction of PCNSL within the East German Study Group for Haematology and Oncology 053 trial. Eligible patients proceeded to high-dose busulfan/thiotepa after induction therapy and mobilization. RESULTS: Data were available from nine patients with a median age of 58 years. The maximal CD34+ cell count per microL of blood after the first course of HD-MTX was 13.89 (median). Determination was repeated in six patients after the second course with a significantly higher median CD34+ cell count of 33.69 per microL. Five patients required two apheresis procedures and in four patients a single procedure was sufficient. The total yield of CD34+ cells per kg of body weight harvested by one or two leukapheresis procedures was 6.60 x 10(6) (median; range, 2.68 x 10(6)-15.80 x 10(6)). The yield of CD34+ cells exceeded the commonly accepted lower threshold of 3 x 10(6) cells per kg of body weight in eight of nine cases. Even in the ninth, hemopoietic recovery after stem cell reinfusion was rapid and safe. CONCLUSION: HD-MTX plus G-CSF is a powerful combination for stem cell mobilization in patients with PCNSL and permits safe conduction of time-condensed and dose-intense protocols with high-dose therapy followed by stem cell reinfusion after HD-MTX induction.

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The objective of this work was to assess the productivity and polysaccharide-protein complex content of Agaricus blazei on rice straw medium, in comparison to conventional sawdust, using four casing soils. The A. blazei strain used was BCRC36814T, purchased from the Food Industry Research and Development Institute, Hsin-Chu, Taiwan. The two media were evaluated as to A. blazei productivity, harvesting time, and production costs. The experimental design used was a randomized complete block, with four replicates. Three local casing soils - Typic Paleudult (CCe), Typic Udorthent (Tq) and Oxyaquic Paleudult (TSp) - were compared to imported peat soil (PS, Saprists, Histosols), used as the control. The productivity of A. blazei using Tq and TSp soil was significantly higher. The TSp casing treatment resulted in earlier harvest by at least 14 to 27 days, when compared to the other treatments. The polysaccharide content in CCe (13.2%) and Tq soils (13.2%) did not differ significantly from the PS (13.4%) and TSp (10.6%) treatments. Local casing soils decreased the production costs of A. blazei cultivation. Composted rice straw can substitute sawdust as the culture medium for A. blazei production with increased yield.

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The objective of this work was to evaluate gas exchange rates, plant height, yield components, and productivity of upland rice, as affected by type and application time of plant growth regulators. A randomized block design, in a 4x2 factorial arrangement, with four replicates was used. Treatments consisted of three growth regulators (mepiquat chloride, trinexapac-ethyl, and paclobutrazol), besides a control treatment applied at two different phenological stages: early tillering or panicle primordial differentiation. The experiment was performed under sprinkler-irrigated field conditions. Net CO2 assimilation, stomatal conductance, plant transpiration, and water-use efficiency were measured four times in Primavera upland rice cultivar, between booting and milky grain phenophases. Gas exchange rates were neither influenced by growth regulators nor by application time. There was, however, interaction between these factors on the other variables. Application of trinexapac-ethyl at both tillering and differentiation stages reduced plant height and negatively affected yield components and rice productivity. However, paclobutrazol and mepiquat chloride applied at tillering, reduced plant height without affecting rice yield. Mepiquat chloride acted as a growth stimulator when applied at the differentiation stage, and significantly increased plant height, panicle number, and grain yield of upland rice.