The fractional-nonlinear robotic manipulator: Modeling and dynamic simulations

In this paper, we applied the Riemann-Liouville approach and the fractional Euler-Lagrange equations in order to obtain the fractional-order nonlinear dynamics equations of a two link robotic manipulator. The aformentioned equations have been simulated for several cases involving: integer and non-integer order analysis, with and without external forcing acting and some different initial conditions. The fractional nonlinear governing equations of motion are coupled and the time evolution of the angular positions and the phase diagrams have been plotted to visualize the effect of fractional order approach. The new contribution of this work arises from the fact that the dynamics equations of a two link robotic manipulator have been modeled with the fractional Euler-Lagrange dynamics approach. The results reveal that the fractional-nonlinear robotic manipulator can exhibit different and curious behavior from those obtained with the standard dynamical system and can be useful for a better understanding and control of such nonlinear systems. © 2012 American Institute of Physics.

Economic relations between Latin America and Asia-Pacific: recent trends and future challenges

Includes bibliography

Structural changes in ocean-liner transport and the challenges facing Latin America and the Caribbean

Revisa la estructura actual del transporte por barcos conferenciantes, analiza las fuerzas que lo estan reestructurando, los problemas que puedan resultar y sugiere posibles cursos de accion.

Isolation, homology modeling and renal effects of a C-type natriuretic peptide from the venom of the Brazilian yellow scorpion (Tityus serrulatus)

Mammalian natriuretic peptides (NPs) have been extensively investigated for use as therapeutic agents in the treatment of cardiovascular diseases. Here, we describe the isolation, sequencing and tridimensional homology modeling of the first C-type natriuretic peptide isolated from scorpion venom. In addition, its effects on the renal function of rats and on the mRNA expression of natriuretic peptide receptors in the kidneys are delineated. Fractionation of Tityusserrulatus venom using chromatographic techniques yielded a peptide with a molecular mass of 2190.64Da, which exhibited the pattern of disulfide bridges that is characteristic of a C-type NP (TsNP, T. serrulatus Natriuretic Peptide). In the isolated perfused rat kidney assay, treatment with two concentrations of TsNP (0.03 and 0.1μg/mL) increased the perfusion pressure, glomerular filtration rate and urinary flow. After 60min of treatment at both concentrations, the percentages of sodium, potassium and chloride transport were decreased, and the urinary cGMP concentration was elevated. Natriuretic peptide receptor-A (NPR-A) mRNA expression was down regulated in the kidneys treated with both concentrations of TsNP, whereas NPR-B, NPR-C and CG-C mRNAs were up regulated at the 0.1μg/mL concentration. In conclusion, this work describes the isolation and modeling of the first natriuretic peptide isolated from scorpion venom. In addition, examinations of the renal actions of TsNP indicate that its effects may be related to the activation of NPR-B, NPR-C and GC-C. © 2013 Elsevier Ltd.

Family planning programmes in Latin America: present situation and new challenges

Includes bibliography

Road Safety in Latin America and the Caribbean: Recent Performance and Future Challenges

This issue of the FAL Bulletin examines road safety performance in Latin America and the Caribbean between 2000 and 2010. It also sets out the need for road safety measures to be incorporated into an integrated and sustainable mobility policy.

Guaranteeing indigenous people's rights in Latin America. Progress in the past decade and remaining challenges. Summary

As the twenty-first century advances, the countries of Latin America are building deeper democracies and looking critically at the development process, in the growing conviction that development should focus on equality and be approached on the basis of rights. This means tackling the region’s persistent inequalities, especially those affecting indigenous peoples, who have historically suffered exclusion and discrimination. It also means guaranteeing indigenous people both the enjoyment of human rights on an equal footing to the rest of society, and the right to be collectively different. This is a challenge for this century, which began with the recognition of the rights of indigenous people and the role they unquestionably play on national and international agendas.

Population ageing in the Caribbean: An inventory of policies, programmes and future challenges

“We must be fully aware that while the developed countries became rich before they became old, the developing countries will become old before they become rich”. This statement made by Gro Harlem Brundtland, World Health Organization (WHO) Director-General, at the World Assembly on Ageing in 2002 in Madrid, reflects the challenges that the developing world is facing in the twentieth century. Population ageing is a global phenomenon, which is having and will have major implications on all aspects of human life in every society. This process is enduring and irreversible, as observed from differing patterns and distinct paces in various regions and countries all over the world. The United Nations has undertaken various efforts to repeatedly draw governments’ attention to the growing demand for answers to these encompassing and profound demographic changes. Various initiatives on the global as well as on the regional and subregional level have been undertaken to highlight the pressing need for concerted action. Of importance in this regard are the numerous agreements reached at the global conferences on social development, population and women orchestrated by the United Nations in the 1990s, which all refer to ageing as an issue of particular concern. The year 1999 was proclaimed by the General Assembly1 of the United Nations as the Year of Older Persons to recognize ageing as one of the major achievements but, at the same time, as one of the major challenges all populations have to cope with in the twentieth century. This continuous call for action culminated in the Second World Assembly on Ageing, which was held in Madrid 2002, where governments agreed to the implementation of a global action plan. This new Plan of Action focuses both on political priorities such as improvements in living conditions of older persons, combating poverty, social inclusion, individual self-fulfilment, human rights and gender equality. To an increasing degree attention is also devoted to such holistic and overarching themes as intergenerational solidarity, employment, social security, health and well-being. Mandated by the Second World Assembly on Ageing, the Population Division of the Economic Commission for Latin America and the Caribbean (ECLAC/CELADE) has convened the Regional Intergovernmental Conference on Ageing in November 2003 in Santiago, where a regional strategy for the implementation (ECLAC, 2003b) of the commitments reached in Madrid has been adopted. Further, a background document (ECLAC 2003a) on the situation of the elderly in the Latin American and Caribbean region, of which this document is a substantive part, has been presented to the meeting. Participating government officials formally committed themselves to work on a national follow-up strategy and to report on the progress made in the implementation of their commitments to the Ad hoc Committee on Population and Development to be convened in 2004.

Hydrodynamic modeling and morphological analysis of Lake Água Preta: one of the water sources of Belém-PA-Brazil

The main contribution from this paper includes the hydrodynamic modeling and morphological analysis of Lake Água Preta in Belém city, Pará State, Brazil. The lake bathymetry was taken through the data provided by COSANPA (the local sanitation and water supply company) dating back to 1975, and from a 2009 field study. Both bathymetries produced two terrain elevation models, which were used for morphological analysis and hydrodynamic simulations. The morphological analysis has revealed that, from 1975 to 2009, the annual mean rate of sedimentation varies between 23,065 and 29,081 m3/year. Through this result, the sedimentation time of Lake Água Preta, from 2009, has been calculated, which varies between 295 and 381 years, maintaining the same rate of sedimentation, water consumption and pumping. The hydrodynamic model simulated the depths and velocities, showing a slight flow with velocities ranging from 0 to 33 cm/s. This flow is established between water input and output of the lake, which is used as reservoir of Belém city.

The sarsaparilla market in the state of São Paulo (Brazil) and the challenges of cultivation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Mathematical modeling and analysis of the flocculation process in chambers in series

In this study, the flocculation process in continuous systems with chambers in series was analyzed using the classical kinetic model of aggregation and break-up proposed by Argaman and Kaufman, which incorporates two main parameters: K (a) and K (b). Typical values for these parameters were used, i. e., K (a) = 3.68 x 10(-5)-1.83 x 10(-4) and K (b) = 1.83 x 10(-7)-2.30 x 10(-7) s(-1). The analysis consisted of performing simulations of system behavior under different operating conditions, including variations in the number of chambers used and the utilization of fixed or scaled velocity gradients in the units. The response variable analyzed in all simulations was the total retention time necessary to achieve a given flocculation efficiency, which was determined by means of conventional solution methods of nonlinear algebraic equations, corresponding to the material balances on the system. Values for the number of chambers ranging from 1 to 5, velocity gradients of 20-60 s(-1) and flocculation efficiencies of 50-90 % were adopted.

Electrically detected magnetic resonance modeling and fitting: An equivalent circuit approach

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Structural properties of beds packed with agro-industrial solid by-products applicable for solid-state fermentation: Experimental data and effects on process performance

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)