Why labor income shares seem to be constant?

The common assumptions that labor income share does not change over time or across countries and that factor income shares are equal to the elasticity of output with respect to factors have had important implications for economic theory. However, there are various theoretical reasons why the elasticity of output with respect to reproducible factors should be correlated with the stage of development. In particular, the behavior of international trade and capital flows and the existence of factor saving innovations imply such a correlation. If this correlation exists and if factor income shares are equal to the elasticity of output with respect to factors then the labor income share must be negatively correlated with the stage of development. We propose an explanation for why labor income share has no correlation with income per capita: the existence of a labor intensive sector which produces non tradable goods.

El control de convencionalidad y la protección del derecho a la propiedad privada a partir de la sentencia del caso Salvador Chiriboga vs. Ecuador (Tema Central)

The contents of this article analyze the right to private property after the decision of the Inter-American Court of Human Rights in the case “Salvador Chiriboga vs. Ecuador”. The author´s concern is the fact that this case represents the most expensive sentence inside the Inter-American protection system due to the violation of the right to private property (art. 21.2 AC); judicial guarantees (art. 8.1 AC) and judicial protection (art. 25.1 CA). This subject has special relevance since Ecuador is facing a judicial reform process and it is necessary to consider that the diffusion of this decision among judges could prevent the commission of the same mistakes; specially, those related to denial of justice as it occurred in the present case study.

Evaluation of the inclusion of a mixture of organic acids or lactulose into the feed of pigs experimentally challenged with Salmonella Typhimurium

A mixture of organic acids and lactulose for preventing or reducing colonization of the gut by Salmonella Typhimurium was evaluated in pigs. A total of 63 4-week-old commercial piglets were randomly distributed into three different experimental dietary groups: a plain diet without additives (PD) and the same diet supplemented with either 0.4% (w/v) formic acid and 0.4% lactic acid (w/v) (AC) or 1% (w/v) lactulose (LC). After 7 days of adaptation, two-thirds of the pigs (14 from each diet) were challenged with a 2-mL oral dose of 10(8) CFU/mL of Salmonella Typhimurium, leaving the remaining animals unchallenged (UC). After 4 and 10 days post-challenge, pigs were euthanized and the ileum and caecum content were aseptically sampled to (a) quantify lactic, formic, and short-chain fatty acids (SCFA), (b) quantify bacterial populations and Salmonella by fluorescence in situ hybridization and (c) qualitatively analyse bacterial populations through denaturing gradient gel electrophoresis (DGGE). Modification of fermentation products and counts of some of the bacterial groups analysed in the challenged pigs receiving the treatments AC and LC were minimal. Treatments only influenced the bacterial diversity after 10 days post-challenge, with AC generating a lower number of DGGE bands than UC(P < 0.05). Neither the inclusion of a mixture of 0.4% (w/v) formic and 0.4% (w/v) lactic acids nor of 1% (w/v) lactulose in the feed influenced numbers of Salmonella in the ileum and caecum of experimentally challenged pigs. (C) 2009 Elsevier B.V. All rights reserved.

Yerba Mate (Ilex paraguariensis) Aqueous Extract Decreases Intestinal SGLT1 Gene Expression but Does Not Affect Other Biochemical Parameters in Alloxan-Diabetic Wistar Rats

Yerba mate (Ilex paraguariensis) is rich in polyphenols, especially chlorogenic acids. Evidence suggests that dietary polyphenols could play a role in glucose absorption and metabolism. The aim of this study was to evaluate the antidiabetic properties of yerba mate extract in alloxan-induced diabetic Wistar rats. Animals (n = 41) were divided in four groups: nondiabetic control (NDC, n = 10), nondiabetic yerba mate (NDY, n = 10), diabetic control (DC, n = 11), and diabetic yerba mate (NDY, n = 10). The intervention consisted in the administration of yerba mate extract in a 1 g extract/kg body weight dose for 28 days; controls received saline solution only. There were no significant differences in serum glucose, insulin, and hepatic glucose-6-phosphatase activity between the groups that ingested yerba mate extract (NDY and DY) and the controls (NDC and DC). However, the intestinal SGLT1 gene expression was significantly lower in animals that received yerba mate both in upper (p = 0.007) and middle (p < 0.001) small intestine. These results indicate that bioactive compounds present in yerba mate might be capable of interfering in glucose absorption, by decreasing SGLT1 expression.

Caracterização de compósitos Nb-20%cu obtidos por moagem de alta energia e sinterizados por fase líquida

In this work, was studied the formation of a composite of the refractory metal niobium with copper, through the process of high-energy milling and liquid phase sintering. The HEM can be used to synthesize composite powders with high homogeneity and fine size particle distribution. It may also produce the solid solubility in immiscible systems such as Nb-Cu, or extend the solubility of systems with limited solubility. Therefore, in the immiscible system Cu-Nb, the high-energy milling was successfully used to obtain the composite powder particles. Initially, the formation of composite particles during the HEM and the effect of preparation technique on the microstructure of the material was evaluated. Four loads of Nb and Cu powders containing 20%wt Cu were synthesized by MAE in a planetary type ball mill under different periods of grinding. The influence of grinding time on the metal particles is evaluated during the process by the withdrawal of samples at intermediate times of milling. After compaction under different forces, the samples were sintered in a vacuum furnace. The liquid phase sintering of these samples prepared by HEM produced a homogeneous and fine grained. The composite particles forming the sintered samples are the addition of a hard phase (Nb) with a high melting point, and a ductile phase (Cu) with low melting point and high thermal and electrical conductivities. Based on these properties, the Nb-Cu system is a potential material for many applications, such as electrical contacts, welding electrodes, coils for generating high magnetic fields, heat sinks and microwave absorbers, which are coupled to electronic devices. The characterization techniques used in this study, were laser granulometry, used to evaluate the homogeneity and particle size, and the X-ray diffraction, in the phase identification and to analyze the crystalline structure of the powders during milling. The morphology and dispersion of the phases in the composite powder particles, as well the microstructures of the sintered samples, were observed by scanning electron microscopy (SEM). Subsequently, the sintered samples are evaluated for density and densification. And finally, they were characterized by techniques of measuring the electrical conductivity and microhardness, whose properties are analyzed as a function of the parameters for obtaining the composite

Obtenção de pós de tântalo metálico a partir da redução aluminotérmica com ignição a plasma

Metallic tantalum has a high commercial value due to intrinsic properties like excellent ductility, corrosion resistance, high melt and boiling points and good electrical and thermal conductivities. Nowadays, it is mostly used in the manufacture of capacitors, due to excellent dielectric properties of its oxides. In the nature, tantalum occurs in the form of oxide and it is extracted mainly from tantalite-columbite ores. The tantalum is usually produced by the reduction of its oxide, using reductants like carbon, silicon, calcium, magnesium and aluminum. Among these techniques, the aluminothermic reduction has been used as the industrial method to produce niobium, tantalum and their alloys, due to the easy removal of the Al and Al2O3 of the system, easing further refining. In conventional aluminothermic reduction an electrical resistance is used to trigger the reaction. This reaction self-propagates for all the volume of material. In this work, we have developed a novel technique of aluminothermic reduction that uses the hydrogen plasma to trigger the reaction. The results obtained by XRD, SEM and EDS show that is possible to obtain a compound rich in tantalum through this technique of aluminothermic reduction in the plasma reactor

Desempenho reprodutivo, características do pelame e taxa de sudação em vacas da raça Braford

Foram investigados os efeitos das características do pelame e da taxa de sudação (TS) sobre o intervalo de partos (IEP, n = 423) e os dias para o parto (DPP, n = 1.202) de vacas da raça Braford criadas em sistema extensivo em região tropical úmida no Mato Grosso do Sul, Brasil. As análises foram realizadas pelo método dos quadrados mínimos considerando para intervalo de partos os seguintes efeitos das classes de idade da vaca ao parto: grupo genético; pai; e regressão sobre a refletância da superfície da capa (R), a espessura da capa (E), o comprimento dos pêlos (C), o número de pêlos por unidade de área (N), o diâmetro dos pêlos (D) e a taxa de sudação. Para dias para o parto, foram considerados os efeitos: R, E, C, N, D, TS, divididos em classes; grupo genético; idade no início da estação de monta; e pai. Os componentes de variância e co-variância foram estimados pelo método de Máxima Verossimilhança Restrita sob o modelo touro. As características adaptativas não foram importantes para a variação do intervalo de parto e dos dias para o parto, mas a taxa de sudação apresentou efeito importante sobre dias ao parto. As estimativas de herdabilidade foram quase nulas para IEP e DPP e maiores para as características adaptativas (E = 0,16 ± 0,09; C = 0,18 ± 0,09; N = 0,08 ± 0,06; D = 0,12 ± 0,07; R = 0,30 ± 0,12; TS = 0,10 ± 0,06). Os resultados obtidos para as correlações genéticas de IEP e DPP com TS e entre as características do pelame indicaram que a seleção simultânea para menores valores de C pode ser favorável à redução do intervalo de partos. em geral, as correlações genéticas entre TS, IEP e DPP apresentaram elevado erro-padrão. Considerando os resultados deste estudo e a importância das características do pelame e da sudação, confirma-se a necessidade de se estudarem as correlações genéticas entre as características adaptativas e o desempenho reprodutivo para o progresso da adaptação de bovinos da raça Braford no Brasil.

Correlações genéticas entre medidas de perímetro escrotal e características produtivas e reprodutivas de fêmeas da raça Nelore

Com objetivo de estimar parâmetros genéticos para perímetro escrotal medido aos 12 (PE12) e aos 18 meses de idade (PE18) de machos e peso a um ano de idade (P365), peso ao primeiro parto (PPP), idade ao primeiro parto (IPP), dias para o primeiro parto (DP) e duração da primeira gestação (DG) medidos em fêmeas, além de correlações entre perímetro escrotal e as demais características, foram analisadas medidas de 9.932 fêmeas e medidas de perímetro escrotal de 14.521 machos Nelore provenientes de 28 rebanhos das regiões Sul e Sudeste do País. Os componentes de (co)variância foram estimados utilizando-se o método da máxima verossimilhança restrita, sob modelo animal, em análises bi-características. As herdabilidades estimadas foram altas para PE12 (0,25 a 0,26), PE18 (0,35 a 0,37), P365 (0,35 e 0,38), PPP (0,40 e 0,41) e DG (0,19 e 0,20) e de menor magnitude para IPP (0,14 e 0,15) e DP (0,05 e 0,06). As correlações genéticas estimadas entre PE12 e P365, PPP, IPP, DP e DG foram de 0,28; 0,30; -0,15; -0,04 e 0,10, respectivamente. As correlações genéticas entre PE18 e P365, PPP, IPP, DP e DG, no entanto, foram de 0,29; 0,32; -0,21; -0,08 e 0,14, respectivamente. Esses resultados sugerem melhorias na eficiência reprodutiva de fêmeas, principalmente quando os rebanhos são selecionados para PE18.

Associações genéticas entre pesos e características reprodutivas em rebanhos da raça Nelore

Dados de 14.918 animais da raça Nelore nascidos entre 1991 e 2000, provenientes de rebanhos localizados nas regiões Sul e Sudeste do País, foram utilizados para estimar componentes de co-variância, herdabilidade e correlações genéticas de peso ao desmame (PD), peso a 1 ano de idade (PA), peso ao sobreano (PS), peso ao primeiro parto (PPP), idade ao primeiro parto (IPP) e dias para o primeiro parto (DP). As estimativas dos componentes de co-variância e dos parâmetros genéticos foram obtidas pelo método de máxima verossimilhança restrita, em análises multivariadas. As herdabilidades estimadas para PD, PA, PS, PPP, IPP e DP foram de 0,26; 0,30; 0,34; 0,35; 0,14 e 0,07, respectivamente. Correlações genéticas negativas foram estimadas entre pesos medidos em diferentes idades e IPP, as quais variaram de -0,31 a -0,16. do mesmo modo, as estimativas de correlação genética entre PD × DP (-0,09); PA × DP (-0,13); PS × DP (-0,17) e PPP × DP (-0,16) foram negativas, embora de menor magnitude. As correlações genéticas estimadas entre as características de crescimento e a IPP foram favoráveis. Assim, a seleção para aumento de peso deve promover redução da IPP. A alta correlação genética estimada entre IPP e DP (0,73) indica que o uso de DP na seleção de bovinos de corte pode promover resposta correlacionada favorável na idade ao primeiro parto.

Morphoquantitative aspects of nitrergic myoenteric neurons from the stomach of diabetic rats supplemented with acetyl-L-carnitine

The NADPH-diaphorase (NADPH-d) positive myoenteric neurons from the body of the stomach of rats with streptozotocin-induced diabetes with or without supplementation with acetyl-L-carnitine (ALC) were evaluated. At the age of 105 days the animals were divided into four groups: normoglycaemic (C), normoglycaemic supplemented with ALC (CC), diabetic (D) and diabetic supplemented with ALC (DC). The supplementation with ALC (200 mg/kg body weight/day) to groups CC and DC was made during 105 days. After this period the animals were killed and the stomach removed and subjected to the histochemical technique of NADPH-d for the staining of the neurons of the myoenteric plexus. The area of 500 neurons of each group was investigated, as well as the neuronal density in an area of 23.84 mm(2) in each stomach. ALC promoted reduction (P < 0.05) of fasting glycaemia, water ingestion and areas of the profiles of the cell bodies of the NADPH-d neurons in the diabetic animals. The density of these neurons was not statistically different in the groups studied. It is suggested, therefore, a moderate neuroprotective effect of ALC, because the diminishment of the areas of the neuronal profiles in the supplemented diabetic animals, although being statistically significant relative to the non-supplemented diabetics, was not sufficient to equal the values from the non-diabetic controls.

Otimização de ELISA empregando a proteína Tc85-11 e planejamento fatorial

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Contribuições para a detecção e identificação de faltas em inversores Multiníveis

This work presents contributions in the detection and identication of faults in multilevel inverters through the study of the converters behavior under these operation conditions. Basically, the approached fault consists of an open-circuit in any switch of a three-level clamped diode inverter. The converter operation is characterized in the pre and post-fault states. A wave form behavior analysis of the pole voltage, phase current and dc-bus current is also done, which highlights characteristics that allow the detection of failure and, even, under favorable conditions, the identication of the faulty device. A compensation strategy of the approached fault (open-switch) is also investigated with the purpose of maintaining the driving system operational when a failure occurs. The proposed topology uses SCRs in parallel with the internal switches of the inverter, which allows, in some occasions, the full utilization of the dc-bus

Alho em pó na alimentação alternativa de frangos de corte

O objetivo deste trabalho foi estudar o efeito da inclusão de alho em pó (Allium sativum) em rações para frangos, sobre desempenho, rendimento de carcaça e partes, peso de órgãos, níveis de colesterol e triacilgliceróis sangüíneos, e morfometria intestinal. Foram utilizados 720 pintainhos machos Cobb, com um dia de idade, distribuídos em blocos casualizados com seis tratamentos: ração sem promotor de crescimento (PC), sem anticoccidiano (AC) e com 0,00, 0,25, 0,50, 0,75 e 1,00% de alho; e ração com PC+AC, com quatro repetições de 30 aves cada. Peso, ganho de peso, consumo de ração, conversão alimentar e mortalidade foram obtidos aos 21 e 42 dias de idade. Aos 42 dias de idade foram abatidas 20 aves por tratamento para determinação do rendimento de carcaça e 4 aves para avaliação do peso de órgãos e morfometria intestinal. Sangue de 8 aves por tratamento foi colhido para determinação de colesterol e triacilgliceróis. em aves alimentadas até 42 dias de idade com ração sem promotor de crescimento e anticoccidiano, a inclusão de até 1,00% de alho em pó beneficiou a conversão alimentar e não alterou o rendimento de carcaça e partes, peso relativo dos órgãos, mucosa intestinal, nem os níveis séricos de colesterol e triacilgliceróis. O alho não substitui com eficiência o antibiótico usado como promotor de crescimento em rações de frangos.

Silagem de grãos úmidos de milho na alimentação de frangos de corte

O objetivo deste trabalho foi avaliar a silagem de grãos úmidos de milho (SGUM) como ingrediente nas rações de frangos de corte, em substituição total aos grãos secos de milho (GSM), no desempenho, no rendimento da carcaça, no peso dos órgãos e na morfologia intestinal. No primeiro experimento, 600 pintainhos machos Ross foram distribuídos em blocos casualizados, com seis tratamentos (A: GSM de 1-42 dias; B: SGUM de 1-42 dias; C: SGUM de 1-7 dias e GSM de 8-42 dias; D: SGUM de 1-14 dias e GSM de 15-42 dias; E: SGUM de 1-21 dias e GSM de 22-42 dias; F: GSM + água de 1-42 dias), com quatro repetições, de 25 aves. No segundo experimento, foram utilizados 24 pintainhos machos Ross, distribuídos ao acaso, em dois tratamentos (com e sem SGUM) e 12 repetições cada. A SGUM até 21 dias de idade não interferiu no desempenho das aves e no rendimento de carcaça aos 42 dias de idade. Frangos alimentados com SGUM apresentaram maior peso relativo do fígado, menor largura das vilosidades do duodeno e íleo, maior altura de vilosidade no jejuno aos 21 dias, e menor profundidade de cripta no duodeno e no íleo aos 42 dias de idade. A SGUM pode ser considerada um ingrediente em dietas de frangos de corte até 21 dias de idade, por não interferir no peso final das aves, no rendimento de carcaça e peso dos órgãos.

Physicochemical properties of endodontic sealers of different bases

Objective: To assess the setting time (ST), flow (FL), radiopacity (RD), solubility (SB) and dimensional change following setting (DC) of different sealers (AH Plus (R), Polifil, Apexit Plus (R), Sealapex (R), Endomethasone (R) and Endofill (R)) according to American National Standards Institute/American Dental Association (ANSI/ADA) Specification 57. Material and methods: Five samples of each material were used for each test. For ST, cast rings were filled with sealers and tested with a Gillmore needle. For FL, the sealer was placed on a glass plate. After 180 s, another plate with 20 g and a load of 100 g were applied on the material, and the diameters of the discs formed were measured. In RD, circular molds were filled with the sealers, radiographed and analyzed using Digora software. For SB, circular molds were filled with the sealers, a nylon thread was placed inside the material and another glass plate was positioned on the set, pressed and stored at 37 degrees C. Samples were weighed, placed in water, dried and reweighed. The water used for SB was analyzed by atomic absorption spectrometry. For DC, circular molds were filled with the sealers, covered by glass plates and stored at 37 degrees C. Samples were measured and stored in water for 30 days. After this period, they were dryed and measured again. Results: Regarding ST, AH Plus (R), Apexit (R) and Endofil (R) sealers are in accordance with ANSI/ADA standards. Endomethasone's manufacturer did not mention the ST; Polifil is an experimental sealer and Sealapex (R) did not set. Considering RD, SB and DC, all sealers were in accordance with ANSI/ADA. The spectrometric analysis showed that a significant amount of K+ and Zn2(+) ions was released from Apexit Plus (R) and Endofill (R), respectively. Conclusion: Except for DC, all other physicochemical properties of the tested sealers conformed to ANSI/ADA requirements.