Welfare and Convergence Speed in the Ramsey Model under two Classes of Gorman Preferences

Using a one-sector, discrete-time Ramsey model, we analyze and compare the implications for welfare, capital accumulation, and speed of convergence to the steady state of two classes of utility functions that represent Gorman preferences, namely homothetic and Stone\u2013Geary preferences. For identical economies, we show that the preference structure does not affect only the capital dynamics and social welfare but also the speed of convergence to the steady-state equilibrium

Seleção de genótipos de aceroleira para produção e qualidade de frutos.

O melhoramento genético de plantas envolve um conjunto de procedimentos, com fundamentação científica, cujo objetivo é a alteração de características das cultivares, de modo que os novos materiais obtidos possibilitem aumento na produtividade e qualidade do produto final. Para isso, o trabalho pode ser dirigido para caracteres com adaptação a elevados teores de elementos tóxicos do solo, resistência a doenças e tolerância a pragas, conformação da copa das plantas mais adequada à colheita, precocidade quanto ao inicio de produção, mudanças no comprimento do ciclo de frutificação e alterações na constituição física e química dos frutos, de modo que o resultado final seja a maior lucratividade do investidor e a maior satisfação do consumidor (LOPES & PAIVA, 2002).pdf 59

Retrieval of the Alzheimer's amyloid precursor protein from the endosome to the TGN is S655 phosphorylation state-dependent and retromer-mediated

Background: Retrograde transport of several transmembrane proteins from endosomes to the trans-Golgi network (TGN) occurs via Rab 5-containing endosomes, mediated by clathrin and the recently characterized retromer complex. This complex and one of its putative sorting receptor components, SorLA, were reported to be associated to late onset Alzheimer's disease (AD). The pathogenesis of this neurodegenerative disorder is still elusive, although accumulation of amyloidogenic Abeta is a hallmark. This peptide is generated from the sucessive β- and γ- secretase proteolysis of the Alzheimer's amyloid precursor protein (APP), events which are associated with endocytic pathway compartments. Therefore, APP targeting and time of residence in endosomes would be predicted to modulate Abeta levels. However, the formation of an APP- and retromer-containing protein complex with potential functions in retrieval of APP from the endosome to the TGN had, to date, not been demonstrated directly. Further, the motif(s) in APP that regulate its sorting to the TGN have not been characterized. Results: Through the use of APP-GFP constructs, we show that APP containing endocytic vesicles targeted for the TGN, are also immunoreactive for clathrin-, Rab 5- and VPS35. Further, they frequently generate protruding tubules near the TGN, supporting an association with a retromer-mediated pathway. Importantly, we show for the first time, that mimicking APP phosphorylation at S655, within the APP 653YTSI656 basolateral motif, enhances APP retrieval via a retromer-mediated process. The phosphomimetic APP S655E displays decreased APP lysosomal targeting, enhanced mature half-life, and decreased tendency towards Abeta production. VPS35 downregulation impairs the phosphorylation dependent APP retrieval to the TGN, and decreases APP half-life. Conclusions: We reported for the first time the importance of APP phosphorylation on S655 in regulating its retromer-mediated sorting to the TGN or lysosomes. Significantly, the data are consistent with known interactions involving the retromer, SorLA and APP. Further, these findings add to our understanding of APP targeting and potentially contribute to our knowledge of sporadic AD pathogenesis representing putative new targets for AD therapeutic strategies

Manipueira e urina de vaca no manejo de mudas de aceroleira infestadas por Meloidogyne javanica.

A aceroleira (Malpighia emaginata) é cultivada comercialmente, na região Nordeste, onde concentra a maior parte da produção de nacional. Em levantamentos realizados nessa região, identificou-se o nematóide do gênero Meloidogyne (nematóide das galhas) como principal problema fitossanitário na cultura, devido à dificuldade de manejo (Ritzinger et al., 2007). O ataque desse nematóide caracteriza-se pela formação de nodulações nas raízes, denominadas ?galhas?. Os danos causados nas raízes, provocam o retardamento no crescimento das mudas até a morte precoce da planta e são, freqüentemente, confundidos com sintomas de deficiências nutricionais ou outras doenças na parte aérea da planta. Estratégias de manejo não químicas como a utilização de resíduos orgânicos e agro-industriais, a exemplo da manipueira (Franco, 1983; Ponte & Franco, 1981; Ponte, 1992), farelo de mamona (Ritzinger & McSorley, 1998; Ritzinger et al., 2008) e a manipueira, foram inicialmente testadas como ação nematicida em 1981. Desde então, tem sido confirmada sua ação fungicida, inseticida, herbicida e até mesmo como adubo foliar por propiciar um melhor desenvolvimento das plantas (Ponte, 1981; Franco, 1983; Ponte, 1992). A urina pode constituir alternativa natural a agrotóxicos e/ou adubos químicos utilizados na agricultura, devido sua composição por substâncias que, reunidas, melhoram a saúde das plantas, tornando-as mais resistentes às pragas e doenças (PESAGRO-RIO, 1992). Desta forma, este trabalho teve o objetivo de avaliar e identificar dosagens nematicidas e/ou fertilizantes dos resíduos agro-industriais, manipueira e urina de vaca, em mudas de aceroleira infestadas pelo nematóide das galhas.pdf 168

Atributos químicos do solo cultivado com genótipos de aceroleira em sistema orgânico.

O Brasil se destaca como o primeiro produtor mundial de acerola, sendo a região Nordeste responsável por 60% da produção nacional. O interesse pela espécie é devido à produção de frutos comestíveis com altos teores de vitamina C. A fertilização é uma prática essencial, uma vez que a aceroleira apresenta elevada demanda de nutrientes em função das várias safras anuais. Além disso, deve-se considerar que a maioria dos pomares de acerola no Brasil estão implantados em solos de baixa fertilidade natural, especialmente em relação a fósforo (Magalhães e Gomes, 2003). O interesse na utilização de resíduos agrícolas, como a torta de mamona, urina de vaca e manipueira entre outros, tem aumentado consideravelmente, não somente pela questão ambiental, mas também pela busca de alternativas que possam favorecer a sustentabilidade do agroecossistema. Estratégias de manejo não químicas, como a utilização de resíduos orgânicos e agro-industriais se bem manejadas possuem potencial para agir como fertilizantes e/ou como biocidas (Ritzinger e Fancelli, 2006). Segundo Zuchi et al. (2007), a torta de mamona também pode ser utilizada como melhorador dos atributos do solo, especialmente os químicos no que tange o suprimento de N, cuja liberação não é tão rápida quanto os fertilizantes químicos nem tão lenta quanto o esterco animal. Neste trabalho objetivou-se avaliar o efeito de resíduos orgânicos na melhoria das características físicas e químicas do solo em diferentes genótipos de aceroleira.pdf 234

Cellulolytic and proteolytic ability of bacteria isolated from gastrointestinal tract and composting of a hippopotamus

The bioprospection for cellulase and protease producers is a promise strategy for the discovery of potential biocatalysts for use in hydrolysis of lignocellulosic materials as well as proteic residues. These enzymes can increment and turn viable the production of second generation ethanol from different and alternative sources. In this context, the goal of this study was the investigation of cellulolytic and proteolytic abilities of bacteria isolated from the gastrointestinal tract of a hippopotamus as well as from its composting process. It is important to highlight that hippopotamus gastrointestinal samples were a non-typical sources of efficient hydrolytic bacteria with potential for application in biotechnological industries, like biofuel production. Looking for this, a total of 159 bacteria were isolated, which were submitted to qualitative and quantitative enzymatic assays. Proteolytic analyzes were conducted through the evaluation of fluorescent probes. Qualitative assays for cellulolytic abilities revealed 70 positive hits. After quantitative analyzes, 44 % of these positive hits were selected, but five (5) strains showed cellulolytic activity up to 11,8 FPU/mL. Regarding to proteolytic activities, six (6) strains showed activity above 10 %, which overpassed results described in the literature. Molecular analyzes based on the identification of 16S rDNA, revealed that all the selected bacterial isolates were affiliated to Bacillus genus. In summary, these results strongly indicate that the isolated bacteria from a hippopotamus can be a potential source of interesting biocatalysts with cellulolytic and proteolytic activities, with relevance for industrial applications.Brazilian research agency (FAPESP)Brazilian research agency (CAPES)Brazilian research agency (CNPq)Univ Fed Sao Paulo, Dept Biol Sci, Rua Sao Nicolau 210, BR-09913030 Sao Paulo, BrazilSao Paulo Zoo Pk Fdn, Av Miguel Estefano 4241, BR-04301905 Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Dept Biophys, Rua 3 Maio,100, BR-04044020 Sao Paulo, SP, BrazilFed Univ Latin Amer Integrat, Latin Amer Inst Life Sci & Nat, Av Tarquinio Joslin Santos 1000, BR-85870901 Foz Do Iguacu, Parana, BrazilUniv Fed Sao Paulo, Dept Biol Sci, Rua Sao Nicolau 210, BR-09913030 Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Biophys, Rua 3 Maio,100, BR-04044020 Sao Paulo, SP, BrazilFAPESP: 2010/51992-5CNPq: 475166/2013-2Web of Scienc

Acúmulo de macronutrientes em plantas de milho adubadas com pó de balão.

Fertbio 2012

Virulence and resistance properties of E. coli isolated from urine samples of hospitalized patients in Rio de Janeiro, Brazil - The role of mobile genetic elements

Extraintestinal pathogenic E. coli (ExPEC) is the most frequent etiological agent of urinary tract infections (UTIs). Particular evolutionary successful lineages are associated with severe UTIs and higher incidences of multidrug resistance. Most of the resistance genes are acquired by horizontal transfer of plasmids and other mobile genetic elements (MGEs), and this process has been associated with the successful dissemination of particular lineages. Here, we identified the presence of MGEs and their role in virulence and resistance profiles of isolates obtained from the urine of hospitalized patients in Brazil. Isolates belonging to the successful evolutionary lineages of sequence type (ST) 131, ST405, and ST648 were found to be multidrug-resistant, while those belonging to ST69 and ST73 were often not. Among the ST131, ST405, and ST648 isolates with a resistant phenotype, a high number of mainly IncFII plasmids was identified. The plasmids contained resistance cassettes, and these were also found within phage-related sequences and the chromosome of the isolates. The resistance cassettes were found to harbor several resistance genes, including blaCTX-M-15. In addition, in ST131 isolates, diverse pathogenicity islands similar to those found in highly virulent ST73 isolates were detected. Also, a new genomic island associated with several virulence genes was identified in ST69 and ST131 isolates. In addition, several other MGEs present in the ST131 reference strain EC958 were identified in our isolates, most of them exclusively in ST131 isolates. In contrast, genomic islands present in this reference strain were only partially present or completely absent in our ST131 isolates. Of all isolates studied, ST73 and ST131 isolates had the most similar virulence profile. Overall, no clear association was found between the presence of specific MGEs and virulence profiles. Furthermore, the interplay between virulence and resistance by acquiring MGEs seemed to be lineage dependent. Although the acquisition of IncF plasmids, specific PAIs, GIs, and other MGEs seemed to be involved in the success of some lineages, it cannot explain the success of different lineages, also indicating other (host) factors are involved in this process. Nevertheless, the detection, identification, and surveillance of lineage-specific MGEs may be useful to monitor (new) emerging clones