904 resultados para Economic growth Effects of differentials in remuneration Mathematical models


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In pineapple fields, weed competition is exacerbated by the fact that the crop is small and has a very slow vegetative development. The objective of this study was to determine the effects of herbicides on growth, yield and quality of pineapple, cultivar 'Pérola'. The experimental design was in randomized blocks with four treatments and four replications. Treatments consisted of weeding by hoe and the herbicides diuron; fluazifop-p-butyl and atrazine + S-metolachlor applied in post-emergence. The characteristics evaluated monthly during the vegetative stage were stem diameter, D-leaf length, number of leaves, number of emitted leaves and percentage of natural floral induction. In the reproductive phase, evaluations were made of average fruit weight (g) with and without crown, fruits length and diameter, number of slip, slip-sucker and sucker type seedlings, determination of soluble solids and pH in the pulp. There was no effect of herbicide treatment on the vegetative growth characteristics. Stem diameter increased until 330 days after planting, showing a decrease after this period. The D-leaf grew over time in all treatments, although phytotoxicity symptoms were observed after the first application of herbicides. The traits evaluated on the reproductive phase showed no significant differences in response to treatments. Therefore, the use of diuron fluazifop-p-butyl and atrazine + S-metolachlor did not affect growth, yield and fruit quality of pineapple, cultivar 'Pérola'.

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Knowledge of the mineral nutrition requirements of mangabeira (Hancornia speciosa Gomes) is relatively scarce and rudimentary because there is a lack of consistent data concerning its nutritional demands at different developmental stages. The aim of this research was to characterize the visual symptoms of macronutrient deficiencies and to evaluate the effects of these deficiencies on the growth, the production of dry matter, and the leaf content of mangabeira. To achieve this goal, a greenhouse experiment was conducted at the Goiano Federal Institute (Instituto Federal Goiano) in Rio Verde - GO, from January to June 2011 in which mangabeira plants were arranged in a random block design and grown in nutrient solutions. This experiment was replicated four times. The plants were treated with either a complete nutrient solution or a nutrient solution from which the individual macronutrient of interest (nitrogen (N), phosphorous (P), potassium (K), magnesium (Mg), calcium (Ca), or sulfur (S) had been omitted. The omission of a macronutrient from the nutrient solution resulted in morphological alterations that were characteristic symptoms of the particular nutritional deficiency and caused decreases in growth and dry matter mass production. The accumulation of macronutrients displayed the following order in mangabeira leaves: N>K>Ca>P>S>Mg.

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[spa] En este trabajo se analizan los efectos sobre la movilidad geográfica de una política pública (SIPTEA) que aumenta la protección por desempleo en Extremadura y Andalucía. Utilizando la discontinuidad geográfica en la política estudiada y datos de los Censos de Población de 1981 y 1991 a nivel municipal, se estima el efecto de SIPTEA en el crecimiento de la población y en las probabilidades de emigrar e inmigrar en áreas rurales que experimentan elevadas tasas de paro y de emigración. Los resultados del trabajo indican que la política mitigó estas pérdidas de población aunque los efectos son cuantitativamente moderados. También se exploran los efectos de dicha política en el ámbito laboral, encontrándose un incremento de la tasa del desempleo asociado a la implementación de la política de entre 10 y 13 puntos porcentuales.

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[spa] En este trabajo se analizan los efectos sobre la movilidad geográfica de una política pública (SIPTEA) que aumenta la protección por desempleo en Extremadura y Andalucía. Utilizando la discontinuidad geográfica en la política estudiada y datos de los Censos de Población de 1981 y 1991 a nivel municipal, se estima el efecto de SIPTEA en el crecimiento de la población y en las probabilidades de emigrar e inmigrar en áreas rurales que experimentan elevadas tasas de paro y de emigración. Los resultados del trabajo indican que la política mitigó estas pérdidas de población aunque los efectos son cuantitativamente moderados. También se exploran los efectos de dicha política en el ámbito laboral, encontrándose un incremento de la tasa del desempleo asociado a la implementación de la política de entre 10 y 13 puntos porcentuales.

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Elevated serum phosphorus, calcium, and fibroblast growth factor 23 (FGF23) levels are associated with cardiovascular disease in chronic renal disease. This study evaluated the effects of sucroferric oxyhydroxide (PA21), a new iron-based phosphate binder, versus lanthanum carbonate (La) and sevelamer carbonate (Se), on serum FGF23, phosphorus, calcium, and intact parathyroid hormone (iPTH) concentrations, and the development of vascular calcification in adenine-induced chronic renal failure (CRF) rats. After induction of CRF, renal function was significantly impaired in all groups: uremic rats developed severe hyperphosphatemia, and serum iPTH increased significantly. All uremic rats (except controls) then received phosphate binders for 4 weeks. Hyperphosphatemia and increased serum iPTH were controlled to a similar extent in all phosphate binder-treatment groups. Only sucroferric oxyhydroxide was associated with significantly decreased FGF23. Vascular calcifications of the thoracic aorta were decreased by all three phosphate binders. Calcifications were better prevented at the superior part of the thoracic and abdominal aorta in the PA21 treated rats. In adenine-induced CRF rats, sucroferric oxyhydroxide was as effective as La and Se in controlling hyperphosphatemia, secondary hyperparathyroidism, and vascular calcifications. The role of FGF23 in calcification remains to be confirmed.

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BACKGROUND AND AIMS: Formerly obese patients having undergone Roux-en-Y gastric bypass (RYGB) display both an accelerated digestion and absorption of carbohydrate and an increased plasma glucose clearance rate after meal ingestion. How RYGB effects postprandial kinetics of dietary lipids has yet not been investigated. METHODS: Plasma triglyceride (TG), apoB48, total apoB, bile acids (BA), fibroblast growth factor 19 (FGF19), and cholecystokinin (CCK) were measured in post-absorptive conditions and over 4-h following the ingestion of a mixed test meal in a cross-sectional, pilot study involving 11 formerly obese female patients 33.8 ± 16.4 months after RYGB surgery and in 11 weight- and age-matched female control participants. RESULTS: Compared to controls, RYGB patients had faster (254 ± 14 vs. 327 ± 7 min, p < 0.05) and lower (0.14 ± 0.04 vs. 0.35 ± 0.07 mM, p < 0.05) peak TG responses, but their peak apoB48 responses tended to be higher (2692 ± 336 vs. 1841 ± 228 ng/ml, p = 0.09). Their postprandial total BA concentrations were significantly increased and peaked earlier after meal ingestion than in controls. Their FGF19 and CCK concentrations also peaked earlier and to a higher value. CONCLUSIONS: The early postprandial apoB48 and BA responses indicate that RYGB accelerated the rate of dietary lipid absorption. The lower postprandial peak TG strongly suggests that the RYGB simultaneously increased the clearance of TG-rich lipoproteins. CLINICAL TRIAL REGISTRATION: NCT01891591.

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Between the mid-nineteenth century and the outbreak of the Spanish Civil War in 1936, Spain undertook a sustained process of economic growth and structural change, but was unable to converge with the core European economies.1 The reasons behind Spain"s failure to converge have been a subject of debate among historians for decades. 2 This dissertation aims to analyze the role played by infrastructure in Spanish economic growth during that period, and tries to find out to what extent the potential shortage or inadequacy of the Spanish infrastructure endowment was one of the factors to blame for the country"s nonconvergence. The dissertation draws on recent research on the economic impact of infrastructure, and on the numerous attempts to measure that impact which have been undertaken in the wake of David Aschauer"s work on the United States.

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Only a few studies have analysed the relationship between intraregional inequality and growth, although several studies have measured inequality at the regional level. The objective of this paper is to analyse the relationship between income (wage) inequality and economic growth in different regions of Mexico. We also try to identify factors that explain the variation of intra-regional inequality across Mexican regions and over time. Using macroeconomic databases and publicly available microdata, we apply techniques used in the fields of statistics and econometrics to obtain robust evidence on the relationship between growth and inequality. Our aim is to provide policy recommendations to support the design and implementation of growth-promoting measures thatavoid the exclusion of certain social groups. This paper provides reasons to use a spatial approach and an analysis of particular regions to avoid «one size fits all» policy recommendations.

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The paper analyses the link between human capital and regional economic growth in the European Union. Using different indicators of human capital calculated from census microdata, we conclude that the recent economic performance of European regions is associated to an increase in overeducation. In fact, measures of educational mismatch seem to have a stronger connection to regional economic performance than other traditional measures of human capital stocks.

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The aim of this investigation was to analyze the dental occlusion in the deciduous dentition, and the effects of orthodontic treatment carried out in the early mixed dentition with the eruption guidance appliance. The deciduous occlusion and craniofacial morphology of 486 children (244 girls and 242 boys) were investigated at the onset of the mixed dentition period (mean age 5.1 years, range 4.0-7.8 years). Treatment in the treatment group and follow-up in the control group were started when the first deciduous incisor was exfoliated (T1) and ended when all permanent incisors and first molars were fully erupted (T2). The mean age of the children was 5.1 years (SD 0.5) at T1 and 8.4 years (SD 0.5) at T2. Treatment was carried out with the eruption guidance appliance. Occlusal changes that took place in 167 children were compared with those of 104 untreated control children. Pre- and post-treatment cephalometric radiographs were taken, and the craniofacial morphology of 115 consecutively treated children was compared with that of 104 control children. The prevalence of malocclusion in the deciduous dentition was 68% or 93% depending on how the cut-off value between the acceptable and non-acceptable occlusal characteristic was defined. The early dentofacial features of children with distal occlusion, large overjet and deepbite differed from those with normal occlusion. However, the skeletal pattern of these three malocclusions showed considerable similarity each being characterized by a retrusive mandible, small maxillo-mandibular difference, convex profile, retrusive lower incisors, and large interincisal angle. In the treatment group, overjet and overbite decreased significantly from T1 to T2. Following treatment, a tooth-to-tooth contact was found in 99% of the treated children but only in 24% of the controls. A Class I molar relationship was observed in 90% of the children in the treatment group, and in 48% in the control group. Good alignment of the incisors was observed in 98% of the treated children, whereas upper crowding was found in 32% and lower crowding in 47% of the controls. A significant difference between the groups was found in the mandibular length, midfacial length and maxillo-mandibular differential. The occlusal correction, brought about by the eruption guidance appliance, was achieved mainly through changes in the dentoalveolar region of the mandible. In addition, the appliance seemed to enhance the growth of the mandible. Treatment in the early mixed dentition using the eruption guidance appliance is an effective method to normalize occlusion and reduce further need of orthodontic treatment. Only few spontaneous corrective changes can be expected without active intervention.

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In the last two decades, cases of corruption have been unveiled in different countries, raising public awareness and reinforcing a trend in which society expects more from their leaders. Our objective in this paper is to examine the effects of corruption and seigniorage on inflation and growth rates. The model used in this article is an extension of the model used by Huang and Wei (2006). We find interesting results and one of them is that, under some conditions, corruption has a positive impact on the growth rate. JEL classification : D73, E52, E58, E62. Keywords : Corruption; Fiscal Policy; Growth; Monetary Policy; Seigniorage.

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Borrelia burgdorferi infektoitujen hiirten antibioottihoidon jälkeinen oireilu Lymen borrelioosi on puutiaisten välittämä monimuotoinen infektiotauti, jonka tunnetuin oire on ns. vaeltava ihottuma eli erythema migrans. Muita tavallisia ilmentymiä ovat erityisesti nivel- ja hermosto-oireet sekä harvemmin sydän- ja silmäoireet. Suurin osa potilaista paranee täysin terveeksi antibioottihoidon avulla, mutta jopa 10 % borrelioosiin sairastuneista oireilee suositusten mukaisesta hoidosta huolimatta. Pitkittyneen oireilun on ajateltu johtuvan mm. infektion laukaisemasta autoimmuunitaudista tai kroonisesta infektiosta, mutta teorioiden tueksi ei ole kyetty esittämään kiistattomia todisteita. Onkin todennäköistä, että antibioottihoidon jälkeisen oireilun takana on useampia mekanismeja eikä yksi teoria selitä kaikkien potilaiden oireilua. Tässä väitöskirjatyössä on tutkittu hoidonjälkeistä borrelioosia hiirimallin avulla. Varhaisvaiheessa (2 viikkoa infektoinnin jälkeen) annettu antibiootti vähensi hiirten nivelturvotusta ja esti B. burgdorferi – bakteerin kasvun kudoksista otetuista näytteissä. Hoidettu¬jen hiirten B. burgdorferi -spesifiset IgG-luokan vasta-aineet pysyivät kuitenkin koholla ja osasta kudosnäytteistä löytyi B. burgdorferi:n DNA:ta PCR-tutkimuksen avulla. Mikäli hiiret hoidettiin myöhäisessä vaiheessa (yli 18 viikkoa infektoinnista) tulokset olivat muuten samanlaiset, mutta keftriaksoni ei vaikuttanut nivelturvotukseen. Näin hiirissä oli aikaansaatu tilanne, joka on hyvin samankaltainen ihmisen hoitoresistentin borrelia-artriitin kanssa: oireet jatkuvat, mutta taudinaiheuttajaa ei saada esiin. Inflammaatiota vaimentavaa anti-TNF-alphaa on käytetty nivelreuman hoidossa menestyksekkäästi huonosti muuhun hoitoon reagoivilla potilailla ja siitä syystä sen ajateltiin voivan vaikuttaa suotuisasti myös B. burgdorferi -infektoitujen hiirten hoidonjälkeiseen nivelturvotukseen. Sillä ei kuitenkaan ollut vaikutusta nivelturvotukseen, mutta yllättäen hoidon jälkeen osa hiirten kudosnäytteistä osoittautui viljelypositiivisiksi. On siis ilmeistä, että hiirimallissamme osa B. burgdorferi spirokeetoista pystyy välttämään keftriaksonihoidon vaikutuksen joko hakeutumalla elimistössä kudokseen, jossa antibiootin pitoisuus ei nouse riittävän korkeaksi, tai ne kykenevät muuntautumaan metabolisesti inaktiiviin tilaan eikä mikrobilääke yhdessä immuunipuolustuksen kanssa onnistu tappamaan niitä. Jatkotutkimuksissa selvitimme B. burgdorferi - spirokeetan mahdollista piilopaikkaa tutkimalla antibioottihoidon jälkeen useita eri kudoksia PCR-menetelmällä. Tulosten perusteella spirokeetta näyttää suosivan nivelkudosta tai soluja, joita esiintyy nivelessä runsaasti. On kuitenkin edelleen epäselvää, missä muodossa B. burgdorferi –spirokeetat säilyvät kudoksessa antibioottihoidon jälkeen.

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We assessed the effects of nutrient enrichment on three stream ecosystems running through distinct biomes (Mediterranean, Pampean and Andean). We increased the concentrations of N and P in the stream water 1.6–4-fold following a before–after control–impact paired series (BACIPS) design in each stream, and evaluated changes in the biomass of bacteria, primary producers, invertebrates and fish in the enriched (E) versus control (C) reaches after nutrient addition through a predictive-BACIPS approach. The treatment produced variable biomass responses (2–77% of explained variance) among biological communities and streams. The greatest biomass response was observed for algae in the Andean stream (77% of the variance), although fish also showed important biomass responses (about 9–48%). The strongest biomass response to enrichment (77% in all biological compartments) was found in the Andean stream. The magnitude and seasonality of biomass responses to enrichment were highly site specific, often depending on the basal nutrient concentration and on windows of ecological opportunity (periods when environmental constraints other than nutrients do not limit biomass growth). The Pampean stream, with high basal nutrient concentrations, showed a weak response to enrichment (except for invertebrates), whereas the greater responses of Andean stream communities were presumably favored by wider windows of ecological opportunity in comparison to those from the Mediterranean stream. Despite variation among sites, enrichment globally stimulated the algal-based food webs (algae and invertebrate grazers) but not the detritus-based food webs (bacteria and invertebrate shredders). This study shows that nutrient enrichment tends to globally enhance the biomass of stream biological assemblages, but that its magnitude and extent within the food web are complex and are strongly determined by environmental factors and ecosystem structure

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We assessed the effects of nutrient enrichment on three stream ecosystems running through distinct biomes (Mediterranean, Pampean and Andean). We increased the concentrations of N and P in the stream water 1.6–4-fold following a before–after control–impact paired series (BACIPS) design in each stream, and evaluated changes in the biomass of bacteria, primary producers, invertebrates and fish in the enriched (E) versus control (C) reaches after nutrient addition through a predictive-BACIPS approach. The treatment produced variable biomass responses (2–77% of explained variance) among biological communities and streams. The greatest biomass response was observed for algae in the Andean stream (77% of the variance), although fish also showed important biomass responses (about 9–48%). The strongest biomass response to enrichment (77% in all biological compartments) was found in the Andean stream. The magnitude and seasonality of biomass responses to enrichment were highly site specific, often depending on the basal nutrient concentration and on windows of ecological opportunity (periods when environmental constraints other than nutrients do not limit biomass growth). The Pampean stream, with high basal nutrient concentrations, showed a weak response to enrichment (except for invertebrates), whereas the greater responses of Andean stream communities were presumably favored by wider windows of ecological opportunity in comparison to those from the Mediterranean stream. Despite variation among sites, enrichment globally stimulated the algal-based food webs (algae and invertebrate grazers) but not the detritus-based food webs (bacteria and invertebrate shredders). This study shows that nutrient enrichment tends to globally enhance the biomass of stream biological assemblages, but that its magnitude and extent within the food web are complex and are strongly determined by environmental factors and ecosystem structure

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The effects of pre-incubation with mercury (Hg2+) and cadmium (Cd2+) on the activities of individual glycolytic enzymes, on the flux and on internal metabolite concentrations of the upper part of glycolysis were investigated in mouse muscle extracts. In the range of metal concentrations analysed we found that only hexokinase and phosphofructokinase, the enzymes that shared the control of the flux, were inhibited by Hg2+ and Cd2+. The concentrations of the internal metabolites glucose-6-phosphate and fructose-6-phosphate did not change significantly when Hg2+ and Cd2+ were added. A mathematical model was constructed to explore the mechanisms of inhibition of Hg2+ and Cd2+ on hexokinase and phosphofructokinase. Equations derived from detailed mechanistic models for each inhibition were fitted to the experimental data. In a concentration-dependent manner these equations describe the observed inhibition of enzyme activity. Under the conditions analysed, the integral model showed that the simultaneous inhibition of hexokinase and phosphofructokinase explains the observation that the concentrations of glucose-6-phosphate and fructose-6-phosphate did not change as the heavy metals decreased the glycolytic flux.