Informe del Seminario Regional sobre Sistemas Ambientales y Estrategias para Ampliar la Frontera Agropecuaria en América Latina = Report of the Regional Seminar on Environmental Systems and Strategies for Extending the Agricultural Frontier in Latin America

Contiene los antecedentes y el resumen de los debates del seminario que tuvo como propósito hacer un aporte a la ejecución del proyecto del mismo nombre cuyo objetivo básico es propiciar metodologías viables que tiendan a disminuir el costo ecológico de las transformaciones y a formar silvoagrosistemas sustentables, y que puedan ser utilizados por los planificadores y encargados de proyectos de desarrollo agrícola y regional en áreas de expansión de frontera agropecuaria.

Planning systems and their enforcement in Latin America

Includes bibliography

Nanotechnology-based drug delivery systems and herbal medicines: a review

Herbal medicines have been widely used around the world since ancient times. The advancement of phytochemical and phytopharmacological sciences has enabled elucidation of the composition and biological activities of several medicinal plant products. The effectiveness of many species of medicinal plants depends on the supply of active compounds. Most of the biologically active constituents of extracts, such as flavonoids, tannins, and terpenoids, are highly soluble in water, but have low absorption, because they are unable to cross the lipid membranes of the cells, have excessively high molecular size, or are poorly absorbed, resulting in loss of bioavailability and efficacy. Some extracts are not used clinically because of these obstacles. It has been widely proposed to combine herbal medicine with nanotechnology, because nano-structured systems might be able to potentiate the action of plant extracts, reducing the required dose and side effects, and improving activity. Nanosystems can deliver the active constituent at a sufficient concentration during the entire treatment period, directing it to the desired site of action. Conventional treatments do not meet these requirements. The purpose of this study is to review nanotechnology- based drug delivery systems and herbal medicines.

Clinical Comparison of the Effectiveness of Single-file Reciprocating Systems and Rotary Systems for Removal of Endotoxins and Cultivable Bacteria from Primarily Infected Root Canals

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

Involutive constrained systems and Hamilton-Jacobi formalism

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

Comparison of cyclic fatigue and torsional resistance in reciprocating single-file systems and continuous rotary instrumentation systems

As compared with continuous rotary systems, reciprocating motion is believed to increase the fatigue resistance of NiTi instruments. We compared the cyclic fatigue and torsional resistance of reciprocating single-file systems and continuous rotary instrumentation systems in simulated root canals. Eighty instruments from the ProTaper Universal, WaveOne, MTwo, and Reciproc systems (n = 20) were submitted to dynamic bending testing in stainless-steel simulated curved canals. Axial displacement of the simulated canals was performed with half of the instruments (n = 10), with back-and-forth movements in a range of 1.5 mm. Time until fracture was recorded, and the number of cycles until instrument fracture was calculated. Cyclic fatigue resistance was greater for reciprocating systems than for rotary systems (P < 0.05). Instruments from the Reciproc and WaveOne systems significantly differed only when axial displacement occurred (P < 0.05). Instruments of the ProTaper Universal and MTwo systems did not significantly differ (P > 0.05). Cyclic fatigue and torsional resistance were greater for reciprocating systems than for continuous rotary systems, irrespective of axial displacement.

Toxin-antitoxin systems and its biotechnological applications

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

Sistemas de cultivo antecessores e doses de nitrogênio em cobertura no feijoeiro em plantio direto = cover crop systems and nitrogen topdressing on common bean in no tillage

The objective of this work was to evaluate the grass cover crop production in crop systems involving maize and Urochloa ruziziensis, and the influence of topdressing nitrogen rates in the yield and agronomic efficiency on common-bean cultivated in succession in no-tillage. The experiments were conducted in Jaboticabal-SP, in a eutrophic red latosol, in the second year of no-tillage system implementation. The IPR 139 cultivar was used in split plot design with three replications, in randomized block. The plots had been composed for three crop systems in the summer season, with maize exclusive, maize intercropped with U. ruziziensis and U. ruziziensis exclusive. The subplots had been constituted for five nitrogen rates (0, 40, 80, 120 and 160 kg ha(-1)), applied as topdressing at V4-4 in irrigated common-bean cultivated in the winter-spring season. The use of U. ruziziensis in crops systems, exclusive or intercropped with maize favors the grass cover crop production sufficiently to total soli surface covered, possibility similar grain yield compared to maize exclusive. The topdressing nitrogen application doesn't affect the common-bean yield in succession to maize and U. ruziziensis intercropped. The increase of nitrogen rates in common-bean in succession to maize exclusive improves the yield, although decreases the agronomic efficiency.

Structure-activity relationship of mastoparan analogs: effects of the number and positioning of Lys residues on secondary structure, interaction with membrane-mimetic systems and biological activity

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

Bovine Tuberculosis in Michigan Wildlife and Livestock

Since 1994, the state of Michigan has recognized a problem with bovine tuberculosis (TB), caused by Mycobacterium bovis, in wild white-tailed deer from a 12-county area in northeastern Lower Michigan. A total of 65,000 free-ranging deer have been tested, and 340 have been found to be positive for M. bovis. The disease has been found in other wildlife species, and, in 1998, in domestic cattle, where to date 13 beef cattle and 2 dairy cattle herds have been diagnosed with bovine TB. Unfortunately, the situation is unique in that there have never been reports of self-sustaining bovine TB in a wild, free-ranging cervid population in North America. Scientists, biologists, epidemiologists, and veterinarians who have studied this situation have concluded that the most logical theory is that high deer densities and the focal concentration caused by baiting (the practice of hunting deer over feed) and feeding are the factors most likely responsible for the establishment of self-sustaining TB in free-ranging Michigan deer. Baiting and feeding have been banned since 1998 in counties where the disease has been found. In addition, the deer herd has been reduced by 50% in the endemic area with the use of unlimited antlerless permits. The measures of apparent TB prevalence have been decreased by half since 1997, providing hopeful preliminary evidence that eradication strategies are succeeding.

Precautionary principle, economic and energy systems and social equity

In this paper the precautionary principle is reviewed alongside the process of international implementation. Adoption of the precautionary principle is advocated to deal with energy choices as a mechanism to account for potential climate change impacts, notwithstanding the debate on scientific uncertainty on the links between solar activity, greenhouse gas concentration and climate. However, it is also recognized that the widespread application of the precautionary principle to energy choices does not seem to be taking place in the real world. Relevant concrete barriers are identified stemming from the intrinsic logic governing the hegemonic economic system, driving the energy choices by economic surplus and rent generation potential, the existence of social asymmetries inside and among societies as well as by the absence of democratic global governance mechanisms, capable of dealing with climate change issues. Such perception seems to have been reinforced by the outcome of the United Nations Climate Change Conference, held in Copenhagen in December 2009. (c) 2010 Elsevier Ltd. All rights reserved.

Internal fit of two all-ceramic systems and metal-ceramic crowns

Objectives: The aim of this study was to investigate the internal fit (IF) of glass-infiltrated alumina (ICA - In-Ceram Alumina), yttria-stabilized tetragonal zirconia polycrystals (Y-TZP - IPS e.max ZirCAD), and metal-ceramic (MC - Ni-Cr alloy) crowns. Material and Methods: Sixty standardized resin-tooth replicas of a maxillary first molar were produced for crown placement and divided into 3 groups (n=20 each) according to the core material used (metal, ICA or Y-TZP). The IF of the crowns was measured using the replica technique, which employs a light body polyvinyl siloxane impression material to simulate the cement layer thickness. The data were analyzed according to the surfaces obtained for the occlusal space (OS), axial space (AS) and total mean (TM) using two-way ANOVA with Tukey's multiple comparison test (p<0.05). Results: No differences among the different areas were detected in the MC group. For the Y-TZP and ICA groups, AS was statistically lower than both OS and TM. No differences in AS were observed among the groups. However, OS and TM showed significantly higher values for ICA and Y-TZP groups than MC group. Comparisons of ICA and Y-TZP revealed that OS was significantly lower for Y-TZP group, whereas no differences were observed for TM. Conclusions: The total mean achieved by all groups was within the range of clinical acceptability. However, the metal-ceramic group demonstrated significantly lower values than the all-ceramic groups, especially in OS.