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1.
J Educ Teach Emerg Med ; 7(3): V1-V5, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37465767

RESUMO

Current guidelines to detect for myocardial infarction (MI) are not sufficient to triage patients requiring immediate cardiac catheterization, with at least 25% of non-ST elevation myocardial infarction (NSTEMI) patients found to have acute coronary occlusion (ACO) only on delayed catheterization, and up to 35% of perceived ST-elevation myocardial infarction (STEMI) ACOs found as false positives at catheterization. There has been a call for an integration of a new paradigm: occlusion/non-occlusion MI (OMI/NOMI). Here we discuss a 51-year-old female who presented to the emergency department with subtle electrocardiogram (ECG) abnormalities not adherent to the current MI guidelines. However, the subtle abnormalities when combined with her history and risk factors point to a high probability of a pathological amount of coronary disease that required immediate catheterization. This case report illustrates the importance in revisiting current guidelines and the need to integrate OMI/NOMI alongside current guidelines to guide decision making for immediate reperfusion needs. Topics: Occlusion, myocardial infarction, ST elevation myocardial infarction, acute coronary syndromes, electrocardiography.

2.
Int J Phytoremediation ; 19(5): 413-424, 2017 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-27748626

RESUMO

Artificial neural networks (ANNs) have been widely used to solve the problems because of their reliable, robust, and salient characteristics in capturing the nonlinear relationships between variables in complex systems. In this study, ANN was applied for modeling of Chemical Oxygen Demand (COD) and biodegradable organic matter (BOD) removal from palm oil mill secondary effluent (POMSE) by vetiver system. The independent variable, including POMSE concentration, vetiver slips density, and removal time, has been considered as input parameters to optimize the network, while the removal percentage of COD and BOD were selected as output. To determine the number of hidden layer nodes, the root mean squared error of testing set was minimized, and the topologies of the algorithms were compared by coefficient of determination and absolute average deviation. The comparison indicated that the quick propagation (QP) algorithm had minimum root mean squared error and absolute average deviation, and maximum coefficient of determination. The importance values of the variables was included vetiver slips density with 42.41%, time with 29.8%, and the POMSE concentration with 27.79%, which showed none of them, is negligible. Results show that the ANN has great potential ability in prediction of COD and BOD removal from POMSE with residual standard error (RSE) of less than 0.45%.


Assuntos
Vetiveria/metabolismo , Recuperação e Remediação Ambiental/métodos , Resíduos Industriais/análise , Redes Neurais de Computação , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Análise da Demanda Biológica de Oxigênio , Recuperação e Remediação Ambiental/instrumentação , Malásia , Indústria Manufatureira , Óleo de Palmeira , Óleos de Plantas , Eliminação de Resíduos Líquidos/instrumentação
3.
J Environ Manage ; 181: 343-352, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27393941

RESUMO

While the oil palm industry has been recognized for its contribution towards economic growth and rapid development, it has also contributed to environmental pollution due to the production of huge quantities of by-products from the oil extraction process. A phytoremediation technique (floating Vetiver system) was used to treat Palm Oil Mill Secondary Effluent (POMSE). A batch study using 40 L treatment tanks was carried out under different conditions and Response Surface Methodology (RSM) was applied to optimize the treatment process. A three factor central composite design (CCD) was used to predict the experimental variables (POMSE concentration, Vetiver plant density and time). An extraordinary decrease in organic matter as measured by BOD and COD (96% and 94% respectively) was recorded during the experimental duration of 4 weeks using a density of 30 Vetiver plants. The best and lowest final BOD of 2 mg/L was obtained when using 15 Vetiver plants after 13 days for low concentration POMSE (initial BOD = 50 mg/L). The next best result of BOD at 32 mg/L was obtained when using 30 Vetiver plants after 24 days for medium concentration POMSE (initial BOD = 175 mg/L). These results confirmed the validity of the model, and the experimental value was determined to be quite close to the predicted value, implying that the empirical model derived from RSM experimental design can be used to adequately describe the relationship between the independent variables and response. The study showed that the Vetiver system is an effective method of treating POMSE.


Assuntos
Análise da Demanda Biológica de Oxigênio , Vetiveria , Indústria Alimentícia , Eliminação de Resíduos Líquidos/métodos , Áreas Alagadas , Biodegradação Ambiental , Resíduos Industriais , Malásia , Modelos Teóricos , Óleo de Palmeira , Óleos de Plantas
4.
Int J Phytoremediation ; 16(5): 429-53, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24912227

RESUMO

The discovery of the arsenic hyperaccumulator, Pteris vittata (Chinese brake fern), has contributed to the promotion of its application as a means of phytoremediation for arsenic removal from contaminated soils and water. Understanding the mechanisms involved in arsenic tolerance and accumulation of this plant provides valuable tools to improve the phytoremediation efficiency. In this review, the current knowledge about the physiological and molecular mechanisms of arsenic tolerance and accumulation in P. vittata is summarized, and an attempt has been made to clarify some of the unresolved questions related to these mechanisms. In addition, the capacity of P. vittata for remediation of arsenic-contaminated soils is evaluated under field conditions for the first time, and possible solutions to improve the remediation capacity of Pteris vittata are also discussed.


Assuntos
Arsênio/metabolismo , Pteris/fisiologia , Poluentes do Solo/metabolismo , Arsênio/análise , Biodegradação Ambiental , Biomassa , Raízes de Plantas/fisiologia , Solo/química , Poluentes do Solo/análise
5.
Int J Phytoremediation ; 13 Suppl 1: 154-65, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22046757

RESUMO

The aim of this study was to investigate effect of calcium on growth, survival, essential oil yield and chemical compositions of vetiver grass grown on lead contaminated soils. Calcium inform of CaCO3 (0, 2000, 4000, 6000 mg Ca kg(-1)) was added to river sand soils containing 4000 mg Pb kg(-1) dry soil. Results showed that, in the absence of calcium treatment, no plants survived after 2 weeks of cultivation, while the rest grew well to the end of the experimental period (42 weeks). Calcium treatments generally resulted in a slight decrease in biomass. Interestingly, an increase in calcium over 2000 mg kg(-1) did not result in a decrease in accumulation of lead in vetiver roots and shoots. The levels of lead in roots and shoots under calcium treatments were around 2000 and 90 mg kg(-1) dry weight, respectively. The addition of CaCO3 did not improve vetiver essential oil yield and chemical composition compared to the control. A level of applied CaCO3 about half of the lead concentration in soils was sufficient to improve vetiver growth and survival, and accumulate high concentrations of lead in the roots. This finding can be applied for re-vegetation of lead contaminated soils using vetiver.


Assuntos
Carbonato de Cálcio/farmacologia , Vetiveria/efeitos dos fármacos , Chumbo/metabolismo , Óleos Voláteis/metabolismo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Biomassa , Sobrevivência Celular , Vetiveria/química , Vetiveria/crescimento & desenvolvimento , Vetiveria/metabolismo , Concentração de Íons de Hidrogênio , Chumbo/análise , Metais Pesados/análise , Metais Pesados/metabolismo , Óleos Voláteis/química , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Solo/química , Poluentes do Solo/análise , Fatores de Tempo
6.
Int J Phytoremediation ; 13(1): 47-60, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21598767

RESUMO

The application of vetiver grass (Chrysopogon zizaniodes) for phytoremediation of heavy metal contaminated soils can be promoted by economic return through essential oil production. Four levels of lead (0, 500, 2000, and 8000 mg kg(-1) dry soil), copper (0, 100, 400, and 1600 mg kg(-1) dry soil) and zinc (0, 400, 1600, and 6400 mg kg(-1) dry soil) were used to study their effects on vetiver growth, essential oil composition and yield. This study also investigated the effect of nitrogen concentrations on vetiver oil yield. Vetiver accumulated high concentrations of Pb, Cu and Zn in roots (3246, 754 and 2666 mg kg(-1), respectively) and small amounts of contaminants in shoots (327, 55, and 642 mg kg(-1), respectively). Oil content and yield were not affected at low and moderate concentrations of Cu and Zn. Only the application of Pb had a significant detrimental effect on oil composition. Extraction of vetiver essential oils by hydrodistillation produced heavy metal free products. High level of nitrogen reduced oil yields. Results show that phytoremediation of Cu and Zn contaminated soils by vetiver can generate revenue from the commercialization of oil extracts.


Assuntos
Vetiveria/metabolismo , Metais Pesados/metabolismo , Poluentes do Solo/metabolismo , Solo/análise , Biodegradação Ambiental , Vetiveria/química , Vetiveria/crescimento & desenvolvimento , Cobre/análise , Cobre/metabolismo , Chumbo/análise , Chumbo/metabolismo , Metais Pesados/análise , Óleos Voláteis/análise , Óleos Voláteis/economia , Extratos Vegetais/análise , Extratos Vegetais/economia , Óleos de Plantas/análise , Óleos de Plantas/economia , Raízes de Plantas/química , Brotos de Planta/química , Poluentes do Solo/análise , Fatores de Tempo , Zinco/análise , Zinco/metabolismo
7.
Int J Phytoremediation ; 11(8): 664-91, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19810597

RESUMO

Glasshouse and field studies showed that Vetiver grass can produce high biomass (>100t/ tha(-1) year(-1)) and highly tolerate extreme climatic variation such as prolonged drought, flood, submergence and temperatures (-15 degrees - 55 degrees C), soils high in acidity and alkalinity (pH 3.3-9.5), high levels of Al (85% saturation percentage), Mn (578 mg kg(-1)), soil salinity (ECse 47.5 dS m(-1)), sodicity (ESP 48%), anda wide range of heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb, Se, and Zn). Vetiver can accumulate heavy metals, particularly lead (shoot 0.4% and root 1%) and zinc (shoot and root 1%). The majority of heavy metals are accumulated in roots thus suitable for phytostabilization, and for phytoextraction with addition of chelating agents. Vetiver can also absorb and promote biodegradation of organic wastes (2,4,6-trinitroluene, phenol, ethidium bromide, benzo[a]pyrene, atrazine). Although Vetiver is not as effective as some other species in heavy metal accumulation, very few plants in the literature have a wide range of tolerance to extremely adverse conditions of climate and growing medium (soil, sand, and railings) combined into one plant as vetiver. All these special characteristics make vetiver a choice plant for phytoremediation of heavy metals and organic wastes.


Assuntos
Biodegradação Ambiental , Vetiveria/metabolismo , Metais Pesados/metabolismo , Compostos Orgânicos/metabolismo , Poluentes Ambientais/química , Poluentes Ambientais/metabolismo , Compostos Orgânicos/química
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