937 resultados para Period Effects
Resumo:
According to Diamond (1977), one of the reasons for the existence of social security systems is that they function as an income redistribution mechanism. There is an extensive literature that tests whether social security systems produce the desired results in developed countries (mainly for the U.S.A.). Nevertheless, there is not an obvious consensus about this social security property and there is little evidence for developing countries. In this article, we test this property for the Brazilian Social Security System. In addition, we also look at another question which has not been answered yet in the previous literature. Is the trend of social security systems increasingly progressive or regressive? We conclude that the changes in Brazilian Social Security legislation reduced inequality between 1987 and 1996, but only for the elderly. For the other age groups, there is a stable trend. Results for the period between 1996 and 2006 reveal that the Brazilian system is neutral for all cohorts. Therefore, we found out that social security systems are not an effective mechanism for income redistribution, as predicted by previous studies.
Resumo:
This paper develops a two-period model with heterogeneous agents to analyze the e¤ects of transfers across locations on convergence, growth and welfare. The model has two important features. First, locations are asymmetric as it is assumed that there are more specialized occupations in the more developed one. Second, the returns on the investment to acquire new technology depend positively on the level of each region’s knowledge and on the level of the world knowledge assumed to be available to all. In one hand, the poor region has a disadvantage as it has a lower stock of knowledge. On the other hand, it has the advantage of not having yet exploited a greater stock of useable knowledge available in the world. Hence, there are two possible cases. When the returns are greater in the poor region, we obtain the following results: (i) the rich location grows slower; (ii) the transfers to the poor location enhances the country’s growth rate; and (iii) there is a positive amount of transfers to the poor region that is welfare improving. When the returns are greater in the rich region, the …rst two results are reversed and transfers to the rich region are welfare improving. In both cases, the optimal amount of transfer increases with the level of income disparity across regions and is not dependent on the level of the country’s economic development (measured by its income per capita). Barriers to the adoption of new technology available in the world can constrain the convergence process as it harms in greater length the poor region. The results do not change whether migration is allowed or not.
Resumo:
Corporate Social Responsibility (CSR) is being implemented in the corporate world at an ever increasing rate, benefitting societies around the world. Several theories have been proposed that contend that the corporations who are implementing CSR programs also benefit financially, making the relationship a symbiotic one. This paper analyzes the financial health of Prime Bank Limited, Bangladesh, (PBL) over a period of a decade in order to determine if PBL has indeed benefited financially from implementing its CSR program. The analysis focuses on examining PBL’s internal and external financial indicators over an extended period of time to determine what the net effect, if any, that the CSR program has had on them. This analysis concludes that the evidence does not support the claim of a causal relationship between CSR spending and positive effects upon PBL, as measured by PBL’s financial indicators.
Resumo:
De acordo com a literatura empírica, há fortes evidências de que, após o controle de características socioeconômicas dos alunos, a qualidade dos professores é o fator mais importante para explicar o desempenho do aluno em testes padronizados. No entanto, não há consenso sobre como sistemas públicos de ensino podem melhorar a qualidade dos professores. Será que o pagamento de salários mais elevados a professores da rede pública impactam a qualidade dos professores nas escolas públicas? O Governo Federal brasileiro introduziu, em 2009, piso salarial nacional para os professores de escolas públicas, provocando um perceptível aumento exógeno dos salários dos professores municipais. O principal objetivo desta tese é avaliar os impactos de curto prazo da elevação linear e incondicional do salário do professor na qualidade da educação. Devido à ausência de dados secundários sobre o valor do salário-base de professores entre 2008 e 2013, tivemos que realizar um levantamento com as Secretarias Municipais de Educação para reunir informação sobre a estrutura da carreira docente e sobre os salários-bases nesse período. Com base em nossa pesquisa de campo, o primeiro capítulo investiga a conformidade dos sistemas municipais de ensino ao piso salarial nacional para professores de redes públicas. Encontramos que fatores não observáveis/observados são determinantes para explicar a variabilidade salarial verificada entre os municípios e o cumprimento da lei, o que embasa nossa estratégia de identificação com base em métodos de diferença em diferenças, combinados com pareamento com base em escore de propensão. O segundo capítulo centra-se na estimativa do impacto da elevação dos salários dos professores sobre a proficiência dos alunos de 5º ano do ensino fundamental municipal. De acordo com estes resultados, o aumento salarial incondicional não gerou uma expansão da proficiência escolar dos alunos, pelo menos no curto prazo. Embora não tenham sido detectados impactos na aprendizagem dos alunos, alguns mecanismos de transmissão do aumento salarial para melhores resultados educacionais podem já ter sido ativados. Assim, o principal objetivo do terceiro capítulo é avaliar o impacto dos aumentos de salário sobre a qualidade dos professores atuais e dos potenciais futuros professores. Avaliamos o impacto de aumentos de salário sobre o desempenho dos professores no ENADE, uma proxy de sua qualidade, e sobre a atratividade dos cursos de ensino superior associados à carreira docente. Essa atratividade é medida por meio da qualidade dos que entram nos respectivos cursos superiores, de acordo com seu desempenho no Enem. Neste último capítulo, aplicamos modelo de Tripla-Diferenças visando controlar dois tipos de potenciais fatores de confusão: (i) mudanças no desempenho dos professores (potenciais futuros professores) entre grupos de municípios, que foram submetidos ao tratamento e os que não foram tratados, que nada têm a ver com a política; e (ii) as alterações no desempenho de todos os professores (alunos) que vivem no município em que houve a elevação salarial devido à introdução da lei. As estimativas obtidas indicam que a elevação salarial gerou efeitos leves sobre a qualidade dos professores e sobre a atratividade dos cursos relacionados à carreira docente.
Resumo:
Tityus serrulatus, popularly known as yellow scorpion, is one of the most studied scorpion species in South America and its venom has supplied some highly active molecules. The effects of T. serrulatus venom upon the renal physiology in human showed increased renal parameters, urea and creatinine. However, in perfused rat kidney the effects were not tested until now. Isolated kidneys from Wistar rats, weighing 240-280 g, were perfused with Krebs-Henseleit solution containing 6% (g weight) of previously dialysed bovine serum albumin. The effects of T. serrulatus venom were studied on the perfusion pressure (PP), renal vascular resistance (RVR), urinary flow (UF), glomerular filtration rate (GFR), sodium tubular transport (%TNa+), potassium tubular transport (%TK+) and chloride tubular transport (%TCl-). Tityus serrulatus venom (TsV; 10 mu g/mL) was added to the system 30 min after the beginning of each experiment (n = 6). This 30 min period was used as an internal control. The mesenteric bed was perfused with Krebs solution kept warm at 37 T by a constant flow (4 mL/min), while the variable perfusion pressure was measured by means of a pressure transducer. The direct vascular effects of TsV (10 mu g/mL/min; n=6), infused at a constant rate (0.1 mL/min), were examined and compared to the infusion of the vehicle alone at the same rate. TsV increased PP (PP30'= 127.8 +/- 0.69 vs PP60' = 154.2 +/- 14 mmHg*, *p < 0.05) and RVR (RVR30' = 6.29 +/- 0.25 vs RVR60' = 8.03 +/- 0.82 mmHg/mL g(-1) min(-1)*, *p < 0.05), decreased GFR (GFR(30') =0.58 +/- 0.02 vs GFR(60') = 0.46 +/- 0.01 mL g(-1) min(-1)*, *p < 0.05) and UF (UF30' = 0.135 +/- 0.001 vs UF60' = 0.114 +/- 0.003 mL g(-1)min(-1)*, *p < 0.05). Tubular transport was not affected during the whole experimental period (120 min). on the other hand, the infusion of TsV (10 mu g/mL/min) increased the basal perfusion pressure of isolated arteriolar mesenteric bed (basal pressure: 74.17 +/- 3.42 vs TsV 151.8 +/- 17.82 mmHg*, *p < 0.05). TsV affects renal haemodynamics probably by a direct vasoconstrictor action leading to decreased renal flow. (c) 2005 Elsevier Ltd. All rights reserved.
Resumo:
O estudo foi efetuado durante o período de chuva (dezembro-fevereiro) em seis viveiros de produção semi-intensiva de peixes, a fim de avaliar o efeito da chuva na qualidade da água de viveiros que apresentam fluxo contínuo de água, a qual é passada de um viveiro para outro sem tratamento prévio. Foram amostrados oito pontos de coleta nas saídas dos viveiros. O viveiro P1 (próximo à nascente) apresentou as menores concentrações físicas e químicas da água e as maiores no viveiro P4 (considerado um ponto crítico recebendo material alóctone proveniente de outros viveiros e do escoamento do setor de criação de rãs). A disposição seqüencial dos viveiros estudados promoveu aumento nas concentrações dos nutrientes, clorofila-a e condutividade. As chuvas características desta época do ano aumentaram o fluxo de água nos viveiros e conseqüentemente, carreando material particulado e dissolvido de um viveiro para outro e, promovendo um aumento das variáveis limnológicas em direção do P3 ao P6. Os resultados sugerem que a chuva no período de estudo afetou positivamente a qualidade da água dos viveiros estudados, porém, como os sistemas analisados estão dispostos em distribuição seqüencial e escoamento constante da água de viveiros e tanques paralelos sem tratamento prévio, cuidados devem ser averiguados para que o aumento do fluxo de água provocado pelas chuvas não tenha efeito adverso nos viveiros estudados.
Resumo:
The cardiopulmonary effects of desflurane and sevoflurane anesthesia were compared in cats breathing spontaneously. Heart (HR) and respiratory (RR) rates; systolic (SAP), diastolic (DAP) and mean arterial (MAP) pressures; partial pressure of end tidal carbon dioxide (PETCO(2)), arterial blood pH (pH), arterial partial pressure of oxygen (PaO(2)) and carbon dioxide (PaCO(2)); base deficit (BD), arterial oxygen saturation (SaO(2)) and bicarbonate ion concentration (HCO(3)) were measured. Anesthesia was induced with propofol (8 +/- 2.3 mg/kg IV) and maintained with desflurane (GD) or sevoflurane (GS), both at 1.3 MAC. Data were analyzed by analysis of variance (ANOVA), followed by the Tukey test (P < 0.05). Both anesthetics showed similar effects. HR and RR decreased when compared to the basal values, but remained constant during inhalant anesthesia and PETCO(2) increased with time. Both anesthetics caused acidemia and hypercapnia, but BD stayed within normal limits. Therefore, despite reducing HR and SAP (GD) when compared to the basal values, desflurane and sevoflurane provide good stability of the cardiovascular parameters during a short period of inhalant anesthesia (T20-T60). However, both volatile anesthetics cause acute respiratory acidosis in cats breathing spontaneously. (c) 2004 ESFM and AAFP. Published by Elsevier Ltd. All rights reserved.
Resumo:
Objectives To investigate the effects of levomepromazine and different desflurane concentrations upon electrocardiographic variables.Animals Twenty adult mongrel dogs of both sexes weighing 6-28 kg.Methods Dogs were divided into two groups of 10 animals. Group I received 1 mg kg(-1) lV of levomepromazine and 15 minutes later anesthesia was induced with propofol (3 mg kg(-1) IV). Desflurane end-tidal concentration was set at 1.6 MAC. After 30 minutes at this concentration, measurements were taken and the end-tidal concentration was reduced to 1.4 MAC. Thereafter, it was reduced to 1.2 and then 1.0 MAC at 1.5-minute intervals. The same procedure was followed for group 2, except that levomepromazine was replaced with 0.2 mL kg(-1) of 0.9% saline solution and more propofol was needed for induction (7 mg kg(-1)). The animals' body temperature was maintained between 38.3 and 39 degreesC using a heating pad. The electrocardiographic tracing was obtained from lead II throughout the experimental period. The measurements were taken immediately before the administration of levomepromazine or placebo (T-1), 15 minutes after pre-medication (T-2) and 30 minutes after the establishment of 1.6 MAC (T-3)The other measurements were made at the concentrations of 1.4, 1.2, and 1.0 MAC, respectively (T4-6). The numerical data were submitted to analysis of variance plus F-test (p < 0.05).Results the dogs that received levomepromazine had a decrease in heart rate. However, in both groups it increased with desflurane administration. Levomepromazine, in association with desflurane, did not induce significant electrocardiographic changes, and all mean values (except P-wave duration) were within the reference range for this species.Conclusions and clinical relevance This study documented that levomepromazine, in association with desflurane, does not induce significant changes in electrocardiographic variables, suggesting that this drug combination has minimal effect on myocardial conduction.
Resumo:
Obejective To study the echocardiographic effects of isoflurane at an end-tidal concentration approximating 1.0 times the minimum alveolar concentration (MAC) in healthy unpremedicated dogs.Study design Prospective experimental trial.Animals Sixteen mature mongrel dogs of either sex weighing 11.06 +/- 2.72 kg.Methods After performing a baseline echocardiogram in the awake animal, anesthesia was induced with increasing inspired concentrations of isoflurane via a face mask until tracheal intubation was possible. Following intubation, the end-tidal concentration was decreased to 1.4% for the rest of the anesthetic period. Serial echocardiograms were recorded at 25, 40, and 55 minutes after the end-tidal concentration was reached.Results No changes were observed in heart rate. However, significant decreases were seen in left ventricular end-diastolic diameter (Mean maximal change: 13.8%), interventricular septal thickness during systole (15.2%), interventricular septal thickening fraction (72.2%), left ventricular free wall thickening fraction (63.5%), ejection fraction (39.9%), and fractional shortening (46.7%). In addition, peak flow velocities across mitral, pulmonic, and aortic valves were significantly lower than baseline values. Decreases were also observed in end-diastolic left ventricular volume index (approximately 32.1% from the awake value), stroke index (58.2%), and cardiac index (55.3%) when compared with awake measurements.Conclusions Our results indicate that 1 x MAC isoflurane caused significant myocardial depression in healthy dogs. These changes in myocardial function need to be considered carefully when isoflurane is to be used in dogs with poor cardiovascular reserve.
Resumo:
Objective To examine the anesthetic effects of a xylazine-diazepam-ketamine (XDK) combination in roosters.Study design Prospective experimental trial.Animals Six healthy white Leghorn roosters weighing 2.03 +/- 0.08 kg.Methods Each rooster was pre-medicated with xylazine (3 mg kg(-1), IM) and after 15 minutes anesthesia was induced with a diazepam (4 mg kg(-1)) and ketamine (25 mg kg(-1)) combination injected into the pectoral muscles. Heart and respiratory rates were recorded before anesthesia and every 15 minutes after induction for 165 minutes. Cloacal temperature was measured before and 15 minutes after pre-medication and every 75 minutes thereafter during anesthesia. Quality of induction and recovery were scored subjectively; duration of loss of righting reflex, abolition of response to a painful stimulus and palpebral reflex were also recorded.Results Intramuscular injection of xylazine smoothly induced loss of the righting reflex within 3-4 minutes. Loss of response to a painful stimulus occurred at 13.1 +/- 2.9 minutes (mean +/- SD) after the administration of the D-K combination, and lasted for 63.0 +/- 5.3 minutes. Roosters anesthetized with this combination had a significant decrease in heart and respiratory rates and cloacal temperature. The recovery period lasted for up to 4 hours (227.5 +/- 15.4 minutes). Quality of recovery was satisfactory for four roosters but excitation was noted in two birds.Conclusions and clinical relevance The XDK combination was a useful anesthetic technique for typhlectomy in roosters. Nevertheless this drug combination should be used with caution and cardiopulmonary parameters monitored carefully. Under the conditions of this experiment it was associated with a decreased cloacal temperature and prolonged recoveries.
Resumo:
In this study, a commercial enzyme immunoassay (EIA) was validated in detecting glucocorticoids in Pampas deer feces, in order to investigate the influence of several factors on the adrenocortical function. Fecal samples, behavioral data and information concerning male grouping and antlers status were collected at a monthly basis during a 1 year period from free-ranging stags living at Emas National Park, Brazil (18 degrees S/52 degrees W). The results revealed that concentrations of fecal glucocorticoids in winter were significantly higher than those corresponding to spring and summer. In addition, dry season data presented higher levels than during the wet season. Significant difference was found between fecal levels of breeding stags in summer and nonbreeding stags, whereas no difference was observed between breeding stags in winter and nonbreeding stags. on the other hand, males from areas with frequent human disturbance exhibited higher glucocorticoid concentrations and flight distances than individuals from areas of lower human activity. Males with antlers in velvet had elevated levels compared with animals in hard antler or antler casting. Also, we found that glucocorticoid levels were higher in groups with three or more males than in groups with only one male. The flight distances showed positive correlation with fecal glucocorticoid. These data indicate that fecal glucocorticoid provides a useful approach in the evaluation of physiological effects of environment, inter-individuals relationship and human-induced stressors on free-ranging Pampas deer stags. (c) 2005 Elsevier B.V. All rights reserved.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
The present work, studied the effect of 0, 1,000, 1,500 and 2,000 mg of garlic powder/kg dry ration for Piaractus mesopotamicus (Osteichthyes Characidae), weighting 73.6+/-39.4 9 and measuring 15.0+/-2.7 cm, fed for a period of 15, 30 and 45 days. Fifteen days after treatment with 1,000 and 2,000 Prig of garlic/kg dry ration, significant reduction of Anacanthorus penilabiatus (Monogenea: Dactylogyridae) in the gills was related. Nevertheless, the addition of garlic to the ration caused significant increase in the erythrocyte number and in the thrombocyte percentage in the circulating blood. However, a decrease in the lymphocyte percentage was also observed. After 45 days, fish fed with garlic showed significant increase in the erythrocyte number, leucocyte, haemoglobin rate, hematocrit and thrombocyte.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)