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Indicadores de sustentabilidade para gestão de resíduos sólidos urbanos
(Universidade Federal de São Carlos, 2008-08-18) Polaz, Carla Natacha Marcolino; Teixeira, Bernardo Arantes do Nascimento; https://lattes.cnpq.br/1166854416745527; https://lattes.cnpq.br/3722828980684272
One way to operationalize the concept of sustainability is through the use of indicators that are useful in planning, monitoring and evaluation steps of Municipal Solid Waste (MSW) policies. They can also help the public managers in setting priorities and goals, providing subsidies for technical decision making. The core objective of this research was to contribute to the development of sustainability indicators for public management of MSW in São Carlos/SP, from the perspective of five dimensions - environmental, economic, social, political and cultural. Based on a prior model proposed by Milanez (2002), the strategy adopted for the indicators adjustment to the São Carlos context was the analysis of the application model process in two consecutive years (2006/2007), followed by the identification of priority problems for the MSW management. For this, managers from two municipal divisions of the São Carlos prefecture, who work in different sectors related to MSW management, were consulted through semi-structured interviews. After the systematization of information obtained from the consultations, an initial proposal of indicators was drawn up. Through a workshop, the first set of indicators was then submitted to some specialists analysis. Both consultation processes (managers and specialists) resulted in the final set, composed of 15 indicators predominantly qualitative, distributed in the five dimensions considered. Of these, seven indicators were kept of the proposed Milanez set, three were adapted from literature and five were drafted from the identification of priorities for the MSW management in São Carlos. For each indicator were characterized the parameters of trend, expressed in three possible conditions: favorable, unfavorable or very unfavorable to sustainability. Since future applications were required to validate this proposal, the results obtained so far showed that the implementing process of a local indicators system should involve the participation of different actors in the selection, review and characterization steps in order to legitimize the effective use of this important management tool. However, the main difference resulting from the adoption of this type of indicator, will be a change in the perception of the general situation of MSW management, in which principles and dimensions of sustainability will be considered.
Efeitos do envelhecimento e do exercício físico sobre o sistema cardiovascular de indivíduos saudáveis
(Universidade Federal de São Carlos, 2008-08-18) Melo, Ruth Caldeira de; Catai, Aparecida Maria; https://lattes.cnpq.br/9437079385922873
The ageing process is known to affect different tissues and systems. It is well-established that age-associated changes in cardiovascular structure and function are related to the risk of cardiovascular diseases. Because of the vast amount of cardiovascular modifications observed with ageing, the present study focused on three important topics: heart rate variability (HRV), blood pressure variability (BPV) and endothelial dysfunction. Furthermore, we also investigated the effects of physical activity (endurance and strength) on the autonomic control of heart rate (HR), which might be used as non-pharmacological therapy. Thirty five young subject between 18 and 30 years old (14 sedentary men, 5 sedentary women and 16 active men) and thirty eight middleaged/older subjects between 55 and 70 years old (16 sedentary men, 14 sedentary women and 8 active men) were studied. In addition, the subjects are distributed among 3 different studies. In the first one, the effects of the ageing process and active life-style on the autonomic control of HR were investigated in young and middleaged/older subjects. Electrocardiogram was recorded during 15 minutes of rest and 4 minutes of controlled breathing (5 to 6 cycles/min) in the supine position. HR and RR intervals were analyzed by time and frequency domain methods. The active groups presented lower HR and higher HRV (time domain) than the sedentary groups, whereas both middle-aged/older groups showed lower HRV (frequency domain). Additionally, interaction between ageing and life-style effects was observed for respiratory sinus arrhythmia (ASR) indexes (calculated during the controlled breathing test). The sedentary middle-aged/older group presented lower ASR magnitude than the other groups studied. The results suggest that ageing reduces HRV, however, regular physical activity improves vagal modulation on the heart and, consequently, attenuates the effects of ageing on the autonomic control of HR. In the second study, we aimed to investigate if strength training is able to improve cardiac autonomic control in healthy middle-aged/older men. HRV was evaluated before and after 12 weeks of isokinetic eccentric strength training (2days/week, 2-4 sets of 8-12 repetitions at 75-80% peak torque), involving knee flexion and extension. Strength training decreased the systolic blood pressure and increased the torque. However, an autonomic imbalance towards sympathetic modulation predominance was induced by an unknown mechanism. In the third study, we evaluated the effect of ageing on the BPV and endothelial function. We also sought for correlations between increased BPV and impaired endothelium dependent-dilation (EDD) in the middle-aged/older group. Intra-brachial artery BPV and conduit vessel EDD (brachial artery flow-mediated dilation, FMD) were determined in healthy young and middle-aged/older subjects. Moreover, endothelial function of resistance vessels was evaluated by venous occlusion plethysmoghaphy in the middle-aged/older group. The young group presented lower systemic oxidative stress, lower systolic BPV and higher FMD compared with the middle-aged/older group. After split this group according to the BPV, lower FMD was observed in the middleaged/older group with higher BPV. In addition, FMD was inversely correlated to BPV. The lower BPV group showed a great reduction (55%) in the forearm blood flow responses when NG-monometyl-L-arginine (nitric oxide inhibitor) was co-infused with acetylcholine (vs 14% in the higher BPV group). The results suggest that ageing process increases BPV and reduces endothelial function. Additionally, middle-aged/older subjects with higher BPV also have impaired EDD compared with their peers with lower BPV. General Conclusions: the results from the studies described above suggest that ageing process causes decrease of HRV, increase of BPV and decrease of endothelial function. Moreover, aerobic exercise has a cardioprotector effect, since it was able to attenuate the ageing effects on the cardiac vagal modulation. This same benefit, however, was not observed after 12 weeks of eccentric strength training. On the other hand, the strength training program performed by healthy older subjects modified the sympato-vagal balance toward the sympathetic modulation. Finally, systolic BPV oscillations seem to have a narrow relationship with vasodilation mediated by nitric oxide. Then, more studies are needed to clarify the cause-effect relation between those important variables.