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Alessandro Jatobá Hugo Cesar Bellas Isabella Koster Rodrigo Arcuri Mario Cesar R. Vidal Paulo Victor R. de Carvalho 《Cognition, Technology & Work》2018,20(1):125-152
In this paper, we study the effects of poor conditions of territories in patient visits performed by community health workers and the consequences to primary care policies. We carried a case study with community health workers in Rio de Janeiro, Brazil, including ethnographic observations in two primary healthcare clinics. Moreover, we present an analysis of the collected data with the support of the function resonance analysis method and we point out relations between the findings and the execution of the primary healthcare policy in a systemic approach. Thus, our study highlights the impacts of work situations in the health assistance of poorly developed communities, indicating how community health workers cope with adverse conditions, and how such situations affect the effectiveness of primary care policies. 相似文献
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Nova Isabella Castoldi Lidia Lietti Luca Tronconi Enrico Forzatti Pio 《Topics in Catalysis》2007,42(1-4):21-25
The reduction process of NOx species stored over Pt-Ba/Al2O3 Lean NOx Trap systems is analysed in this paper when H2 is used as a reductant. The effect of different experimental conditions (temperature, reductant concentration, adsorption
lengths, etc.) is addressed and discussed in relation to the selectivity and the efficiency of the reduction process. 相似文献
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The unsteady-state kinetics of the selective catalytic reduction (SCR) of NO with NH3 is studied over V2O5–WO3/TiO2 model catalysts by means of the transient response method. NH3 strongly adsorbs onto the catalyst surface whereas NO does not adsorb appreciably. A dynamic mathematical model based on a Temkin-type desorption process for NH3 and a SCR reaction rate with a complex dependence on the ammonia surface coverage is well suited to represent the data. 相似文献
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Morton A. Barlaz Christopher A. Bareither Azam Hossain Jovita Saquing Isabella Mezzari Craig H. Benson Thabet M. Tolaymat Ramin Yazdani 《Canadian Metallurgical Quarterly》2010,136(8):839-853
The objective of this research was to examine the performance of five North American bioreactor landfills. This paper represents the second of a two-part series and addresses biological and chemical aspects of bioreactor performance including gas production and management, and leachate chemistry. The data support accelerated methane generation at several landfills (k = 0.08–0.21?1/year) relative to the AP-42 default decay rate (k = 0.04?1/year). While the data indicate that gas collection increases at bioreactor landfills, a general relationship between decay rate and moisture added or wet weight water content could not be identified. There was no indication that gas collection increases appreciably when the water content reaches 40%. Most of the leachates at the landfills in this study were commingled from cells operating as a bioreactor and conventionally. Nevertheless, trends in pH and BOD:COD in the bioreactor leachates were consistent with the impacts of enhanced biological activity. Ammonia concentrations also increased over time but remained below levels reported to be inhibitory. For both heavy metals and speciated organic chemicals, there was no indication that bioreactor landfill leachate is significantly different from leachate generated at conventional landfills. 相似文献
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Fernanda Andreola Luisa Barbieri E. Karamanova Isabella Lancellotti Mario Pelino 《Ceramics International》2008
In the present work, the feasibility to substitute feldspar raw material in a porcelain stoneware body with Panel Cathode Ray Tube (CRT) glass was investigated. A standard batch and a composition, where 35 wt.% Na-feldspar was substituted by CRT glass, were sintered at different temperatures in the range of 1000–1250 °C. The degree of the densification was studied by evaluation of the closed and total porosity, while the sintering rate was estimated by non-isothermal dilatometric measures. The variation of the crystalline phase composition was evaluated by XRD analysis. From the preliminary study other ceramic samples with different percentages of CRT glass (i.e. 2.5, 5 and 10 wt.%) were prepared and fired in industrial kiln. The sintering parameters, the microstructure and the mechanical properties were measured and compared with the standard composition. 相似文献
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G Doronzo M Viretto I Russo L Mattiello G Anfossi M Trovati 《International journal of molecular sciences》2012,13(8):9478-9488
Type 1 diabetes is characterized by insulin deficiency, type 2 by both insulin deficiency and insulin resistance: in both conditions, hyperglycaemia is accompanied by an increased cardiovascular risk, due to increased atherosclerotic plaque formation/instabilization and impaired collateral vessel formation. An important factor in these phenomena is the Vascular Endothelial Growth Factor (VEGF), a molecule produced also by Vascular Smooth Muscle Cells (VSMC). We aimed at evaluating the role of high glucose on VEGF-A(164) synthesis and secretion in VSMC from lean insulin-sensitive and obese insulin-resistant Zucker rats (LZR and OZR). In cultured aortic VSMC from LZR and OZR incubated for 24 h with d-glucose (5.5, 15 and 25 mM) or with the osmotic controls l-glucose and mannitol, we measured VEGF-A(164) synthesis (western, blotting) and secretion (western blotting and ELISA). We observed that: (i) d-glucose dose-dependently increases VEGF-A(164) synthesis and secretion in VSMC from LZR and OZR (n = 6, ANOVA p = 0.002-0.0001); (ii) all the effects of 15 and 25 mM d-glucose are attenuated in VSMC from OZR vs. LZR (p = 0.0001); (iii) l-glucose and mannitol reproduce the VEGF-A(164) modulation induced by d-glucose in VSMC from both LZR and OZR. Thus, glucose increases via an osmotic mechanism VEGF synthesis and secretion in VSMC, an effect attenuated in the presence of insulin resistance. 相似文献
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Rahman MA Penco M Peroni I Ramorino G Grande AM Di Landro L 《ACS applied materials & interfaces》2011,3(12):4865-4874
The development of materials with the ability of intrinsic self-repairing after damage in a fashion resembling that of living tissues has important scientific and technological implications, particularly in relation to cost-effective approaches toward damage management of materials. Natural rubbers with epoxy functional groups in the macromolecular chain (ENR) and ethylene-methacrylic acid ionomers having acid groups partially neutralized with metal ions possess self-repairing behavior following high energy impacts. This research investigates the self-repairing behavior of both ENR and ionomers during ballistic puncture test on the basis of their thermal and mechanical properties. Heterogeneous blending of ionomers and ENR have also been used here as a strategy to tune the thermal and mechanical properties of the materials. Interestingly, blends of sodium ion containing ionomer exhibit complete self-repairing behavior, whereas blends of zinc ion containing ionomer show limited mending. The chemical structure studied by FTIR and thermal analysis shows that both ion content of ionomer and functionality of ENR have significant influence on the self-repairing behavior of blends. The mobility of rubbery phases along with its interaction to ionomer phase in the blends significantly changes the mending capability of materials. The healing behavior of the materials has been discussed on the basis of their thermal, mechanical, and rheological tests for each materials. 相似文献