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1.
Sci Total Environ ; 721: 137727, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32182461

RESUMO

According to the Floods Directive (Directive 60/2007/EC), the management of floods represents an obligation of each EU member state to defend human lives as well as the economic well-being of societies, especially in areas defined as critical. The purpose of this study was to develop a flood attenuation model based on detention basins in the 23 critical flood risk zones of continental Portugal, capable to eliminate the high and very high flood risk areas instead of attempting to ensure full control of the flood in all potentially threatened areas. The model workflow comprised the sequential use of engineering formulae based on historical peak flows and a zoning algorithm embedded in a Geographic Information System. The formulas allowed to set up the volume of river water to retain in a detention basin during a flood, as well as the smallest catchment area (A) producing this volume. The results were divided into sustainable (h ≤ 8 m) or non-sustainable (h > 8 m) detention basins. Thus, these results indicated the possibility to install 27 sustainable and 75 non-sustainable detention basins in specific catchments within the critical zones contributing watersheds. The number of sustainable detention basins is reduced by about 30% when the full flood control model is used. Because the construction of non-sustainable (engineered) dams is extremely costly, the only possible way to mitigate flood risk in these critical zones would be to couple flood attenuation with hydroelectric use, or through the implementation of an extensive reforestation program in the catchment with the purpose to increase evapotranspiration and reduce runoff.

2.
Sci Total Environ ; 681: 242-257, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31103662

RESUMO

A Partial Least Squares-Path Model (PLS-PM) was developed for the Ave River Basin (North of Portugal), and the results used in a scenario analysis. The data for PLS-PM comprised a set of anthropogenic pressures, water quality parameters, and a macroinvertebrate-based biodiversity index (IPtIN) used to assess the ecological status of streams. These groups of measured parameters (called latent variables) were given the names "Pressures", "Contamination" and "Ecological Integrity". Besides, latent variables were connected through path coefficients representing potential causal effects among them. In a large portion of Ave the ecological status of streams is currently bad or poor. Nitrate and coliforms were the most weighted measured variables of latent variable "Contamination", with w ≈ 0.7 and w ≈ 0.2, respectively. The highest "Pressures" weights were ascribed to livestock farming (0.7) and population density (0.4). The connections "Pressures"-"Contamination" and "Contamination" - "Ecological Integrity" exposed a sequence of direct negative effects between the three variables, expressed in the corresponding path coefficients (pc = 0.87 and pc = -1.11). Paradoxically, a direct negative effect of "Pressures" over "Ecological Integrity" was absent (pc = 0.29). Therefore, the poor ecological status of local stream waters might not be directly related to the presence of potentially threatening contaminant sources (the "Pressures"), but to ineffective monitoring of livestock farming and wastewater treatment activities that potentiate (accidental) releases of contaminants into the streams. The lack of a direct link "Pressures" - "Ecological Integrity" supported the results of pressure change versus IPtIN change scenarios. Regardless of some significant reductions of anthropogenic activity and population density until 2027, announced by the Portuguese Environmental Agency, the scenarios could not predict improvement of ecological status beyond the "moderate" category. The study recommendations were therefore to prevent contamination through proper implementation and monitoring of existing watershed management plans. The adequate treatment of domestic effluents and the control of livestock farming residues are urgent.


Assuntos
Monitoramento Ambiental/métodos , Invertebrados/fisiologia , Modelos Teóricos , Animais , Biodiversidade , Ecologia , Análise dos Mínimos Quadrados , Nitratos , Portugal , Rios , Águas Residuárias , Qualidade da Água
3.
Sci Total Environ ; 613-614: 1079-1092, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28950670

RESUMO

Rainwater harvesting (RWH) is used to support small-scale agriculture and handle seasonal water availability, especially in regions where populations are scattered or the costs to develop surface or groundwater resources are high. However, questions may arise as whether this technique can support larger-scale irrigation projects and in complement help the struggle against wildfires in agro-forested watersheds. The issue is relevant because harvested rainwater in catchments is usually accumulated in small-capacity reservoirs created by small-height dams. In this study, a RWH site allocation method was improved from a previous model, by introducing the dam wall height as evaluation parameter. The studied watershed (Sabor River basin) is mostly located in the Northeast of Portugal. This is a rural watershed where agriculture and forestry uses are dominant and where ecologically relevant regions (e.g., Montezinho natural park) need to be protected from wildfires. The study aimed at ranking 384 rainfall collection sub-catchments as regards installation of RWH sites for crop irrigation and forest fire combat. The height parameter was set to 3m because this value is a reference to detention basins that hold sustainability values (e.g., landscape integration, environmental protection), but the irrigation capacity under these settings was smaller than 10ha in 50% of cases, while continuous arable lands in the Sabor basin cover on average 222ha. Besides, the number of sub-catchments capable to irrigate the average arable land was solely 7. When the dam wall height increased to 6 and 12m, the irrigation capacity increased to 46 and 124 sub-catchments, respectively, meaning that more engineered dams may not always ensure all sustainability values but warrant much better storage. The limiting parameter was the dam wall height because 217 sub-catchments were found to drain enough water for irrigation and capable to store it if proper dam wall heights were used.

4.
J Wound Care ; 25(11): 635-640, 2016 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-27827275

RESUMO

OBJECTIVE: To evaluate and compare the costs of using a transparent polyurethane film (PF) and hydrocolloid dressing (HD) in the prevention of pressure ulcers (PUs). METHOD: This descriptive, observational, longitudinal, comparative study was conducted in the intensive care units, coronary care unit and medical clinic of a charity hospital in Brazil. Data were collected during a 30-day study period, consisting of physical examination, assessment of risk factors for PU development and application of the Braden scale, which were performed at inclusion in the study and once daily during hospitalisation. Either PF or HD was applied bilaterally in the sacral and trochanteric regions for prevention of PUs in patients at a moderate to high risk of PUs according to the Braden scale, and costs of using PU preventive dressings were estimated. RESULTS: The mean total costs per dressing change per patient when using the HD and PF to prevent PUs were 413.60 BRL and 74.04 BRL, respectively. There were significant between-group differences in mean costs for all variables, except for saline solution and nurse-technician services. CONCLUSION: Results showed that the mean cost per dressing change per patient was lower when using the transparent PF than when using the HD.


Assuntos
Curativos Hidrocoloides/economia , Curativos Oclusivos/economia , Poliuretanos/uso terapêutico , Úlcera por Pressão/terapia , Cicatrização/fisiologia , Brasil , Custos e Análise de Custo , Feminino , Humanos , Masculino
5.
Phys Rev Lett ; 116(14): 147202, 2016 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-27104723

RESUMO

All quantum optomechanics experiments to date operate at cryogenic temperatures, imposing severe technical challenges and fundamental constraints. Here, we present a novel design of on-chip mechanical resonators which exhibit fundamental modes with frequencies f and mechanical quality factors Q_{m} sufficient to enter the optomechanical quantum regime at room temperature. We overcome previous limitations by designing ultrathin, high-stress silicon nitride (Si_{3}N_{4}) membranes, with tensile stress in the resonators' clamps close to the ultimate yield strength of the material. By patterning a photonic crystal on the SiN membranes, we observe reflectivities greater than 99%. These on-chip resonators have remarkably low mechanical dissipation, with Q_{m}∼10^{8}, while at the same time exhibiting large reflectivities. This makes them a unique platform for experiments towards the observation of massive quantum behavior at room temperature.

6.
Opt Lett ; 39(13): 3868-71, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24978758

RESUMO

A sensing configuration for fluid evaporation monitoring using a suspended-core fiber tip is proposed. Strong differences between the evaporation processes of acetone and isopropyl alcohol were observed, both in terms of the signal's intensity fluctuations and total duration. In each fluid, the main signal variations were due to changes in reflectivity inside a collapsed region of the suspended-core fiber near the spliced interface with a standard single-mode fiber. After further analysis with a wider array of substances, this configuration could, in the future, be used to detect and study the evaporation of different volatile organic compounds.

7.
Intervirology ; 40(4): 247-52, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9612726

RESUMO

We report five cases of human disease caused by arbovirus in 5 patients from the State of São Paulo, Brazil, residing in the municipalities of Osasco, Atibaia, Guarujá, and the capital São Paulo, respectively. One of the patients resides in São Luis, capital of the State of Maranhão. The sites of infection probably were the states of Paraná and Goiás, both in cave regions, the State of Amazonas, and Rondônia in two cases. Laboratory tests for malaria were negative and 1 patient showed a positive serum reaction for leptospirosis. Serum samples from the acute and convalescent phases were tested by hemagglutination inhibition, complement fixation, and neutralization in mice. Acute phase samples were inoculated into suckling mice by the intracerebral route. A close antigenic relationship was observed between the five agents isolated and the flavivirus Ilheus. Serologic tests demonstrated the absence of antibodies in all samples from the 5 patients during convalescence and even for more than 1 year after infection in 1 of them.


Assuntos
Infecções por Arbovirus/virologia , Infecções por Flaviviridae/virologia , Flaviviridae , Adulto , Idoso , Animais , Infecções por Arbovirus/imunologia , Brasil , Flaviviridae/classificação , Flaviviridae/isolamento & purificação , Flaviviridae/ultraestrutura , Infecções por Flaviviridae/imunologia , Humanos , Masculino , Camundongos
8.
Rev Port Cardiol ; 14(5): 395-9, 360, 1995 May.
Artigo em Português | MEDLINE | ID: mdl-7654400

RESUMO

STUDY OBJECTIVE: To determine the safety of ciprofibrate in portuguese patients with dyslipidaemia. DESIGN: Open-label study with 6-month therapy. PARTICIPANTS: Sequential sample of 40 patients, 20 from each hospital, 37 patients (92.5%) completed the study. METHODS: After at least one month of diet or washout period, all participants were given 100 mg/day of ciprofibrate, taken after the evening meal. Analysis and clinical examinations were performed at weeks (-4), (0), (+8), (+16) and (+24). Glycemia, uric acid, creatine kinase, creatinine and transaminases were determined. MAIN RESULTS: Thirty-seven patients ended the study (92.5%), three abandoned because of gastrointestinal adverse effects, six other patients also complaint of gastrointestinal side effects. The creatinine and creatine kinase levels increased 9.7% and 19.2%, although kept in the normal range. There were no statistically significant changes in glycemia, uric acid and transaminases levels. CONCLUSIONS: These results confirm the high safety of ciprofibrate in patients with dislipidaemia. The short term of this study does not allows taking conclusions about long term use of this drug.


Assuntos
Ácido Clofíbrico/análogos & derivados , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Adolescente , Adulto , Idoso , Ácido Clofíbrico/uso terapêutico , Feminino , Ácidos Fíbricos , Humanos , Masculino , Pessoa de Meia-Idade , Portugal
9.
Rev Port Cardiol ; 14(4): 313-22, 284, 1995 Apr.
Artigo em Português | MEDLINE | ID: mdl-7612280

RESUMO

STUDY OBJECTIVE: To determine the efficacy of ciprofibrate in portuguese patients with hypercholesterolaemia, hypertriglyceridaemia and mixed hyperlipidaemia. DESIGN: Open-label study with 6-month therapy. SETTING: Out-patient clinics of two Central Hospitals. PARTICIPANTS: Sequential sample of 40 patients 20 from each hospital. 37 patients (92.5%) completed the study; 14 had dyslipidaemia type IIa, 12 type IIb and 11 type IV. METHODS: After at least one month of diet or washout period, all participants were given 100 mg/day of ciprofibrate, taken after the evening meal. Analysis and clinical examinations were performed at weeks (-4), (0), (+8), (+16) and (+24). Total (TC) and HDL (HDL-C) cholesterol, triglycerides (TG), apoproteins A-I, B100, and (a), and fibrinogen were determined. LDL-cholesterol (LDL-C) was calculated by means of the Friedewald formula, whenever TG < or = 400 mg/dl. MAIN RESULTS: With ciprofibrate, in the whole population, TC, TG, LDL-C, apoB100, and TC/HDL-C ratio diminished, respectively 16.6%, 46.2%, 20.7%, 12.6% and 24.6%. HDL-C and apoA-I increased 10.4% and 4.2%. LDL-C was reduced by 29.5% (p = 0.0001) in type IIa patients, and increased 23% (not statistically significant) in type IV patients. The reduction of TG attained 57.4% in type IIb patients. One type IIb patient received 200 mg/day of the drug from week (+16) on. BMI, waist/hip ratio, hypertension, alcohol consumption and sex didn't affect ciprofibrate activity. CONCLUSIONS: These results confirm the high efficacy of ciprofibrate in patients with hypercholesterolaemia, hypertriglyceridaemia and mixed hyperlipidaemia. In type IIa dyslipidaemia, the reduction of LDL-C was roughly equivalent to that of the less potent statins. In type IV dyslipidaemia LDL-C may increase moderately. The influence on apoprotein (a) and fibrinogen was positive but modest.


Assuntos
Ácido Clofíbrico/análogos & derivados , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Adolescente , Adulto , Idoso , Ácido Clofíbrico/uso terapêutico , Feminino , Ácidos Fíbricos , Humanos , Masculino , Pessoa de Meia-Idade , Portugal , Fatores de Tempo
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