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1.
J Neonatal Perinatal Med ; 14(2): 203-211, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32894255

RESUMO

BACKGROUND: Brazil is a large country with an elevated incidence of Chlamydiatrachomatis (CT) and Neisseriagonorrhoeae (NG) during pregnancy and variable access to health care. The objective of the study was to identify ophthalmia neonatorum prophylaxis practices in the country. METHODS: A prospective multidisciplinary survey was conducted using a closed social media group. Fifteen questions were developed after literature review. Specific content included categorization of respondents and practices such as type of medication, age at administration, occurrence of clinical and/or chemical conjunctivitis and microbiology identification. Questions were multiple choice, but some allowed written response. RESULTS: A total of 1.015 professionals responded, representing 24 states (92%) and 181 cities; mainly neonatologists (64%) and general pediatricians (21%). 96% of respondents reported performing prophylaxis at their institutions, mostly at birth or <1 h of life (99%), and regardless the mode of delivery (73%). Frequently used medications are: 1% silver nitrate (64%), 2.5% povidone iodine (18%) or 10% silver vitelinate (12%), with some regional variations. Occurrence of chemical conjunctivitis was stated by 58% of the respondents and microbiology identification was unusual. CONCLUSIONS: Ophthalmia neonatorum prophylaxis Brazil is almost universal and mainly performed by the use of anti-septic medications, with some regional variability. However, identification and treatment of CT and NG in both parents and newborns is not accomplished.


Assuntos
Atitude do Pessoal de Saúde , Oftalmia Neonatal/prevenção & controle , Padrões de Prática Médica/estatística & dados numéricos , Brasil , Humanos , Oftalmia Neonatal/tratamento farmacológico , Povidona-Iodo/uso terapêutico , Prevalência , Estudos Prospectivos , Nitrato de Prata/uso terapêutico
2.
Water Sci Technol ; 79(5): 985-992, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31025978

RESUMO

The wastewater from food-processing industries is generally heavily charged with lipids and proteins. Flotation process is commonly applied to separate the hydrophobic material phase, producing flotation froth, a waste that has high levels of fats and proteins. Enzymatic hydrolysis may be used to overcome the difficulty of fat biotransformation in a subsequent anaerobic digestion. In the present work, wastes from the flotation process of two industries (dairy and poultry slaughterhouse) were hydrolyzed with a commercial lipase and without enzyme addition (control). The effect of adjusting the pH at the beginning of the hydrolytic assays was also investigated. The long chain free fatty acids (LCFAs) released were identified and quantified and 5-d digestion assays were conducted with the hydrolyzed material. The results indicated that the hydrolysis assays conducted with initial pH adjusted to 7.0 and the utilization of a commercial enzyme promoted a higher increase in amounts of LCFAs, particularly of unsaturated acids. In most anaerobic digestion assays, the specific methane production showed a decreasing trend with the increase of unsaturated fatty acids in the medium. In general, the utilization of a commercial enzyme (lipase) in the hydrolysis process did not contribute to enhancing methane production in 5-d anaerobic digestion assays.


Assuntos
Matadouros , Indústria de Processamento de Alimentos , Carne , Eliminação de Resíduos Líquidos/métodos , Resíduos/análise , Anaerobiose , Reatores Biológicos , Hidrólise , Metano
3.
J Perinatol ; 38(1): 80-85, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29095433

RESUMO

OBJECTIVE: To determine short-term outcomes of infants with evidence of hypoxia-ischemia at birth and classified as mild neonatal encephalopathy (NE) at <6 h of age. STUDY DESIGN: Prospective multicenter study. Mild NE was defined as ⩾1 abnormal category in modified Sarnat score. Primary outcome was any abnormality on early amplitude integrated electroencephalogram (aEEG) or seizures, abnormal brain magnetic resonance imaging (MRI) or neurological exam at discharge. RESULTS: A total of 54/63 (86%) of enrolled infants had data on components of the primary outcome, which was abnormal in 28/54 (52%): discontinuous aEEG (n=4), MRI (n=9) and discharge exam (n=22). Abnormal tone and/or incomplete Moro were the most common findings. MRI abnormalities were confined to cerebral cortex but two infants had basal ganglia and/or thalamus involvement. The 18 to 24 months follow-up is ongoing. CONCLUSIONS: A larger than expected proportion of mild NE infants with abnormal outcomes was observed. Future research should evaluate safety and efficacy of neuroprotection for mild NE.


Assuntos
Encéfalo/patologia , Eletroencefalografia , Hipóxia-Isquemia Encefálica/diagnóstico , Convulsões/etiologia , Canadá , Feminino , Humanos , Hipotermia Induzida/métodos , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Exame Neurológico , Valor Preditivo dos Testes , Estudos Prospectivos , Convulsões/diagnóstico , Índice de Gravidade de Doença
4.
Ultramicroscopy ; 160: 247-251, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26555324

RESUMO

This paper presents a 3D computational framework for evaluating electrostatic properties of a single field emitter characterized by the hemisphere-on-post geometry. Numerical simulations employed the finite elements method by using Ansys-Maxwell software. Extensive parametric simulations were focused on the threshold distance from which the emitter field enhancement factor (γ) becomes independent from the anode-substrate gap (G). This investigation allowed demonstrating that the ratio between G and the emitter height (h) is a reliable reference for a broad range of emitter dimensions; furthermore, results permitted establishing G/h ≥ 2.2 as the threshold condition for setting the anode without affecting γ.

5.
Arch Dis Child Fetal Neonatal Ed ; 100(5): F428-31, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26063193

RESUMO

OBJECTIVE: To determine periextubation practices in extremely preterm infants (<28 weeks gestation). DESIGN: A survey consisting of 13 questions related to weaning from mechanical ventilation, assessment of extubation readiness and postextubation respiratory support was developed and sent to clinical directors of level III NICUs in Australia, Canada, Ireland, New Zealand and USA. A descriptive analysis of the results was performed. RESULTS: 112/162 (69%) units responded; 36% reported having a guideline (31%) or written protocol (5%) for ventilator weaning. Extubation readiness was assessed based on ventilatory settings (98%), blood gases (92%) and the presence of clinical stability (86%). Only 54% ensured that infants received caffeine ≤24 h prior to extubation. 16% of units systematically extubated infants on the premise that they passed a Spontaneous Breathing Test with a duration ranging from 3 min (25%) to more than 10 min (35%). Nasal continuous positive airway pressure was the most common type of respiratory support used (84%) followed by nasal intermittent positive pressure ventilation (55%) and high-flow nasal cannula (33%). Reintubation was mainly based on clinical judgement of the responsible physician (88%). There was a lack of consensus on the time frame for definition of extubation failure (EF), the majority proposing a period between 24 and 72 h; 43% believed that EF is an independent risk factor for increased mortality and morbidity. CONCLUSIONS: Periextubation practices vary considerably; decisions are frequently physician dependent and not evidence based. The definition of EF is variable and well-defined criteria for reintubation are rarely used. High-quality trials are required to inform guidelines and standardise periextubation practices.


Assuntos
Extubação , Protocolos Clínicos , Lactente Extremamente Prematuro , Padrões de Prática Médica , Desmame do Respirador/métodos , Austrália , Canadá , Pressão Positiva Contínua nas Vias Aéreas , Humanos , Ventilação com Pressão Positiva Intermitente , Irlanda , Nova Zelândia , Inquéritos e Questionários , Estados Unidos
6.
Environ Technol ; 36(13-16): 2052-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25690305

RESUMO

Petroleum refineries produce large amount of wastewaters, which often contain a wide range of different compounds. Some of these constituents may be recalcitrant and therefore difficult to be treated biologically. This study evaluated the capability of an aerobic submerged fixed-bed reactor (ASFBR) containing a corrugated PVC support material for biofilm attachment to treat a complex and high-strength organic wastewater coming from a petroleum refinery. The reactor operation was divided into five experimental runs which lasted more than 250 days. During the reactor operation, the applied volumetric organic load was varied within the range of 0.5-2.4 kgCOD.m(-3).d(-1). Despite the inherent fluctuations on the characteristics of the complex wastewater and the slight decrease in the reactor performance when the influent organic load was increased, the ASFBR showed good stability and allowed to reach chemical oxygen demand, dissolved organic carbon and total suspended solids removals up to 91%, 90% and 92%, respectively. Appreciable ammonium removal was obtained (around 90%). Some challenging aspects of reactor operation such as biofilm quantification and important biofilm constituents (e.g. polysaccharides (PS) and proteins (PT)) were also addressed in this work. Average PS/volatile attached solids (VAS) and PT/VAS ratios were around 6% and 50%, respectively. The support material promoted biofilm attachment without appreciable loss of solids and allowed long-term operation without clogging. Microscopic observations of the microbial community revealed great diversity of higher organisms, such as protozoa and rotifers, suggesting that toxic compounds found in the wastewater were possibly removed in the biofilm.


Assuntos
Biofilmes/crescimento & desenvolvimento , Reatores Biológicos/microbiologia , Compostos Orgânicos/isolamento & purificação , Petróleo/microbiologia , Águas Residuárias/microbiologia , Purificação da Água/métodos , Aerobiose/fisiologia , Compostos Orgânicos/metabolismo , Petróleo/análise , Poluição por Petróleo/prevenção & controle , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/análise
7.
Pediatr Pulmonol ; 50(5): 479-86, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25603969

RESUMO

BACKGROUND: Rates of extubation failure of extremely preterm infants remain high. Analysis of breathing patterns variability during spontaneous breathing under endotracheal tube continuous positive airway pressure (ETT-CPAP) is a potential tool to predict extubation readiness. OBJECTIVE: To investigate if automated analysis of respiratory signals would reveal differences in respiratory behavior between infants that were successfully extubated or not. METHODS: Respiratory Inductive Plethysmography (RIP) signals were recorded during ETT-CPAP just prior to extubation. Signals were digitized, and analyzed using an Automated Unsupervised Respiratory Event Analysis (AUREA). Extubation failure was defined as reintubation within 72 hr. Statistical differences between infants who were successfully extubated or failed were calculated. RESULTS: A total of 56 infants were enrolled and one was excluded due to instability during the ETT-CPAP; 11 out of 55 infants studied failed extubation (20%). No differences in demographics were observed between the success and failure groups. Significant differences on the variability of some respiratory parameters or 'metrics' estimated by AUREA were observed between the 2 groups. Indeed, a simple classification using the variability of two metrics of respiratory behavior predicted extubation failure with high accuracy. CONCLUSION: Automated analysis of respiratory behavior during a short ETT-CPAP period may help in the prediction of extubation readiness in extremely preterm infants.


Assuntos
Algoritmos , Processamento Eletrônico de Dados/métodos , Lactente Extremamente Prematuro , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Desmame do Respirador/métodos , Pressão Positiva Contínua nas Vias Aéreas/métodos , Feminino , Humanos , Recém-Nascido , Intubação Intratraqueal , Masculino , Pletismografia/métodos
8.
Early Hum Dev ; 88(12): 925-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23058298

RESUMO

Mechanical ventilation is a resource-intensive complex medical intervention associated with high morbidity. Considerable practice style variation exists in most hospitals and is not only confusing for parents, but the lack of consistently high standard of optimal ventilation deprives some infants of the benefits of state-of-the-art care. Developing a unit protocol for mechanical ventilation requires exhaustive research, inclusion of all stake-holders, thoughtful protocol development and careful implementation after a thorough educational process, followed by monitoring. A protocol for respiratory support should be comprehensive, addressing respiratory support in the delivery room, the use of non-invasive support, intubation criteria, surfactant administration, specific ventilation modes and settings, criteria for escalating therapy, weaning protocols, extubation criteria, and post-extubation management. Evidence favors the use of non-invasive support as first line treatment, progressing to assist/control or pressure support ventilation combined with volume guarantee, if needed, and high-frequency ventilation only for specific indications. The open lung strategy is crucial to lung-protective ventilation.


Assuntos
Respiração Artificial/métodos , Protocolos Clínicos/normas , Humanos , Recém-Nascido , Recém-Nascido Prematuro
9.
Clin Perinatol ; 39(3): 543-62, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22954268

RESUMO

Protracted mechanical ventilation is associated with increased morbidity and mortality in preterm infants and thus the earliest possible weaning from mechanical ventilation is desirable. Weaning protocols may be helpful in achieving more rapid reduction in support. There is no clear consensus regarding the level of support at which an infant is ready for extubation. An improved ability to predict when a preterm infant has a high likelihood of successful extubation is highly desirable. In this article, available evidence is reviewed and reasonable evidence-based recommendations for expeditious weaning and extubation are provided.


Assuntos
Respiração Artificial/métodos , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Desmame do Respirador/métodos , Corticosteroides/uso terapêutico , Extubação , Sistema Nervoso Autônomo/fisiopatologia , Cafeína/uso terapêutico , Diuréticos/uso terapêutico , Humanos , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Recém-Nascido , Recém-Nascido Prematuro , Apoio Nutricional , Modalidades de Fisioterapia , Síndrome do Desconforto Respiratório do Recém-Nascido/fisiopatologia , Fatores de Risco
10.
Braz J Med Biol Res ; 45(5): 425-35, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22473319

RESUMO

This study investigated the influence of cueing on the performance of untrained and trained complex motor responses. Healthy adults responded to a visual target by performing four sequential movements (complex response) or a single movement (simple response) of their middle finger. A visual cue preceded the target by an interval of 300, 1000, or 2000 ms. In Experiment 1, the complex and simple responses were not previously trained. During the testing session, the complex response pattern varied on a trial-by-trial basis following the indication provided by the visual cue. In Experiment 2, the complex response and the simple response were extensively trained beforehand. During the testing session, the trained complex response pattern was performed in all trials. The latency of the untrained and trained complex responses decreased from the short to the medium and long cue-target intervals. The latency of the complex response was longer than that of the simple response, except in the case of the trained responses and the long cue-target interval. These results suggest that the preparation of untrained complex responses cannot be completed in advance, this being possible, however, for trained complex responses when enough time is available. The duration of the 1st submovement, 1st pause and 2nd submovement of the untrained and the trained complex responses increased from the short to the long cue-target interval, suggesting that there is an increase of online programming of the response possibly related to the degree of certainty about the moment of target appearance.


Assuntos
Condicionamento Psicológico/fisiologia , Sinais (Psicologia) , Movimento/fisiologia , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
11.
Artigo em Inglês | MEDLINE | ID: mdl-23367206

RESUMO

The majority of extreme preterm infants require endotracheal intubation and mechanical ventilation (ETT-MV) during the first days of life to survive. Unfortunately this therapy is associated with adverse clinical outcomes and consequently, it is desirable to remove ETT-MV as quickly as possible. However, about 25% of extubated infants will fail and require re-intubation which is also associated with a 5-fold increase in mortality and a longer stay in the intensive care unit. Therefore, the ultimate goal is to determine the optimal time for extubation that will minimize the duration of MV and maximize the chances of success. This paper presents a new objective predictor to assist clinicians in making this decision. The predictor uses a modern machine learning method (Support Vector Machines) to determine the combination of measures of cardiorespiratory variability, computed automatically, that best predicts extubation readiness. Our results demonstrate that this predictor accurately classified infants who would fail extubation.


Assuntos
Extubação , Coração/fisiologia , Recém-Nascido Prematuro , Fenômenos Fisiológicos Respiratórios , Humanos , Recém-Nascido
12.
J Perinatol ; 32(4): 270-5, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21738121

RESUMO

OBJECTIVE: The objective of this study was to evaluate the occurrence of adverse effects during surfactant delivery, using a standardized protocol for administration and management of complications. STUDY DESIGN: The protocol was developed, implemented and used for 6 months. Vital signs and ventilatory parameters were prospectively recorded during the procedure. Infants were classified into three groups, based on the occurrence and severity of complications: no, minor or major. RESULT: A total of 39 infants received surfactant and 19 presented some complication: 11 minor and 8 major. Six of the major complications were episodes of severe airway obstruction (SAO) and five occurred in extreme low birth weight (ELBW) infants that had more severe lung disease before surfactant delivery. Two cases of persistent pulmonary hypertension occurred in infants with birth weight>1000 g. CONCLUSION: This study identified a high rate of SAO and provides data to support changes in the protocol, which should include faster and more robust increases in positive inspiratory pressures in ELBW infants presenting with SAO.


Assuntos
Obstrução das Vias Respiratórias/etiologia , Surfactantes Pulmonares/administração & dosagem , Surfactantes Pulmonares/efeitos adversos , Síndrome do Desconforto Respiratório do Recém-Nascido/tratamento farmacológico , Feminino , Humanos , Hipertensão Pulmonar/etiologia , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Ventilação com Pressão Positiva Intermitente , Masculino , Estudos Prospectivos , Fatores de Risco
13.
Water Sci Technol ; 58(10): 1971-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19039177

RESUMO

Biosolids production in the activated sludge process generates an additional cost to wastewater treatment plants due to the growing requirements for sludge treatment and disposal. This work focuses on the application of ozonation to reduce sludge production in an industrial wastewater treatment plant. The results show that ozonation was able to promote cell wall rupture, releasing intracellular matter into the liquid medium. This effect was observed by the increase in concentrations of DNA (1.14 to 7.83 mg/L) and proteins (0.5 to 45.602 mg/L) in the liquid phase, when ozonation was applied during 10 min, using 30 mg/L of ozone. Reduction of sludge production was assessed by calculating the observed sludge yield coefficient (Y) in bench-scale continuous experiments conducted with varying proportions of ozonated sludge in the recycle stream and recycle ratios. Reduction of sludge production ranged from 14 to 39%, depending on the experimental conditions. The best result in terms of sludge excess reduction was achieved when 20% of the recycle sludge was ozonated and the recycle ratio was 0.67.


Assuntos
Resíduos Industriais , Ozônio/química , Esgotos/microbiologia , Eliminação de Resíduos Líquidos , Purificação da Água/métodos , Conservação dos Recursos Naturais , DNA/metabolismo , Concentração de Íons de Hidrogênio , Oxirredução , Oxigênio/isolamento & purificação , Proteínas/metabolismo , Solubilidade , Fatores de Tempo
14.
Chemosphere ; 69(11): 1815-20, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17644156

RESUMO

This work was conducted to investigate the possibility of using stillage from ethanol distilleries as substrate for sulfate reducing bacteria (SRB) growth and to evaluate the removal efficiency of heavy metals present in wastewaters containing sulfates. The experiments were carried out in a continuous bench-scale Upflow Anaerobic Sludge Blanket reactor (13 l) operated with a hydraulic retention time of 18 h. The bioreactor was inoculated with 7 l of anaerobic sludge. Afterwards, an enrichment procedure to increase SRB numbers was started. After this, cadmium and zinc were added to the synthetic wastewater, and their removal as metal sulfide was evaluated. The synthetic wastewater used represented the drainage from a dam of a metallurgical industry to which a carbon source (stillage) was added. The results showed that high percentages of removal (>99%) of Cd and Zn were attained in the bioreactor, and that the removal as sulfide precipitates was not the only form of metal removal occurring in the bioreactor environment.


Assuntos
Bactérias Anaeróbias/crescimento & desenvolvimento , Carbono/química , Etanol/química , Metais Pesados/análise , Esgotos/microbiologia , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Microscopia Eletrônica
15.
Dev Med Child Neurol ; 49(7): 539-41, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17593128

RESUMO

The case of a term, male neonate (birthweight 3785g) with cephalic presentation, Caesarean-section (C-section) delivery, and failure to thrive is reported. The infant presented with generalized hypotonia and respiratory failure immediately following birth. An initial diagnosis of hypoxic-ischemic encephalopathy was made. However, ventilator dependency and slow recovery of generalized tonus over the following weeks could not be explained. Late cervical magnetic resonance imaging showed extensive syringomyelia from C2 to C7. To the authors' knowledge, this is the first report of syringomyelia after a C-section delivery following cephalic presentation without any associated abnormalities. Follow-up at 2 years of age revealed no improvement on neurological examination: poor head control, difficulty swallowing, flaccid paralysis of upper limbs, and spasticity of lower limbs with exacerbated deep reflexes and spontaneous clonus. Difficulties in establishing the diagnosis and managing the case are discussed.


Assuntos
Cesárea/efeitos adversos , Insuficiência Respiratória/etiologia , Siringomielia/etiologia , Pré-Escolar , Seguimentos , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Siringomielia/patologia
16.
Environ Technol ; 28(2): 147-55, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17396408

RESUMO

The physico-chemical characteristics and the acute toxicity of several wastewater streams, generated in the industrial production of synthetic rubber, were determined. The acute toxicity was evaluated in bioassays using different organisms: Danio rerio (fish), Lactuca sativa (lettuce) and Brachionus calyciflorus (rotifer). The removal of toxicity attained in the industrial wastewater treatment plant was also determined upstream and downstream of the activated sludge process. The results obtained indicate that the critical streams in terms of acute toxicity are the effluents from the liquid polymer unit and the spent caustic butadiene washing stage. The biological treatment was able to partially remove the toxicity of the industrial wastewater. However, a residual toxicity level persisted in the biotreated wastewater. The results obtained with Lactuca sativa showed a high degree of reproducibility, using root length or germination index as evaluation parameters. The effect of volatile pollutants on the toxicity results obtained with lettuce seeds was assessed, using ethanol as a model compound. Modifications on the assay procedure were proposed. A strong correlation between the toxic responses of Lactuca sativa and Danio rerio was observed for most industrial effluent streams.


Assuntos
Indústria Química , Resíduos Industriais/efeitos adversos , Poluentes Químicos da Água/toxicidade , Animais , Brasil , Butadienos , Germinação/efeitos dos fármacos , Dose Letal Mediana , /crescimento & desenvolvimento , Petróleo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Rotíferos/efeitos dos fármacos , Eliminação de Resíduos Líquidos , Peixe-Zebra
17.
Biotechnol Lett ; 28(6): 447-53, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16614912

RESUMO

Newly designed group-specific PCR primers for denaturing gradient gel electrophoresis (DGGE) were used to investigate foaming mycolata from a bioreactor treating an industrial saline waste-water. Genetic profiles on DGGE gels were different with NaCl at 1.65 and 8.24 g l(-1), demonstrating that mycolata community was affected by salinity. A semi-nested PCR strategy resulted in more bands in community genetic profiles than direct amplification. DNA sequencing of bands confirmed the efficacy of the novel primers with sequences recovered being most similar to foam producing mycolata. The new group-specific primers/DGGE approach is a new step toward a more complete understanding of functionally important groups of bacteria involved in biological treatment of waste-water.


Assuntos
Actinobacteria/genética , Primers do DNA/genética , Resíduos Industriais/análise , Reação em Cadeia da Polimerase/métodos , Gerenciamento de Resíduos/métodos , Actinobacteria/isolamento & purificação , Biodegradação Ambiental , Ecossistema , Eletroforese em Gel de Poliacrilamida , Ácidos Micólicos/química , RNA Ribossômico 16S/classificação , Análise de Sequência de DNA/métodos , Purificação da Água/métodos
18.
J Hazard Mater ; 137(1): 178-84, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16530949

RESUMO

The performance of several oxidation processes to remove organic pollutants from sourwater was investigated. Sourwater is a specific stream of petroleum refineries, which contains slowly biodegradable compounds and toxic substances that impair the industrial biological wastewater treatment system. Preliminary experiments were conducted, using the following processes: H2O2, H2O2/UV, UV, photocatalysis, ozonation, Fenton and photo-Fenton. All processes, except Fenton and photo-Fenton, did not lead to satisfactory results, reducing at most 35% of the sourwater dissolved organic carbon (DOC). Thus, further experiments were performed with these two techniques to evaluate process conditions and organic matter removal kinetics. Batch experiments revealed that the Fenton reaction is very fast and reaches, in a few minutes, an ultimate DOC removal of 13-27%, due to the formation of iron complexes. Radiation for an additional period of 60 min can increase DOC removal up to 87%. Experiments were also conducted in a continuous mode, operating one 0.4L Fenton stirred reactor and one 1.6L photo-Fenton reactor in series. DOC removals above 75% were reached, when the reaction system was operated with hydraulic retention times (HRT) higher than 85 min. An empirical mathematical model was proposed to represent the DOC removal kinetics, allowing predicting process performance quite satisfactorily.


Assuntos
Resíduos Industriais , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Desenho de Equipamento , Peróxido de Hidrogênio/química , Cinética , Modelos Teóricos , Oxidantes , Oxidantes Fotoquímicos , Oxirredução , Oxigênio/química , Petróleo , Poluentes Químicos da Água
19.
Pediatr Pulmonol ; 40(3): 270-4, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15988736

RESUMO

Pulmonary lymphangiectasia is a rare cause of respiratory distress in the newborn associated with a very poor outcome. We describe three premature newborns presenting at birth with nonimmune hydrops, bilateral chylothorax, and severe respiratory distress in the immediate newborn period secondary to pulmonary lymphangiectasia. We review the similarities of these cases and discuss their antenatal and neonatal course. One patient survived and is thriving at 9 months of age. With continuing advances in antenatal and neonatal care, an improved outcome may be possible in what was previously described as a uniformly fatal condition.


Assuntos
Hidropisia Fetal/etiologia , Pneumopatias/congênito , Pneumopatias/complicações , Linfangiectasia/congênito , Linfangiectasia/complicações , Síndrome do Desconforto Respiratório do Recém-Nascido/etiologia , Evolução Fatal , Humanos , Hidropisia Fetal/diagnóstico , Hidropisia Fetal/terapia , Recém-Nascido , Recém-Nascido Prematuro , Pneumopatias/diagnóstico , Pneumopatias/terapia , Linfangiectasia/diagnóstico , Linfangiectasia/terapia , Masculino , Síndrome do Desconforto Respiratório do Recém-Nascido/diagnóstico , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia
20.
Chemosphere ; 57(7): 711-9, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15488934

RESUMO

The removal of pollutants in saline medium by the Fenton's reagent needs a more detailed investigation, since the presence of chloride may inhibit or retard degradation. Phenol was used as a model pollutant and the influence of some important process variables for the removal of total organic carbon and phenol were investigated, such as FeSO4 and H2O2 concentrations, pH and salinity. The reactivity of iron cations and alternative procedures of applying UV radiation (photo-Fenton) were evaluated. Phenol was fast and completely removed by the Fenton's process even in a high saline medium (50,000mg NaCll(-1)). However, TOC was only moderately or poorly removed in saline media, depending on the salt concentration. When the photo-Fenton process was used, mineralization was improved and high TOC removals were observed in moderately saline media (NaCl concentration < or =10,000mgl(-1)). For the highest NaCl concentration tested (50,000mgl(-1)) only a moderate TOC removal was observed (50%).


Assuntos
Peróxido de Hidrogênio/química , Ferro/química , Fenol/química , Raios Ultravioleta , Poluição Química da Água/prevenção & controle , Carbono/química , Cromatografia Líquida de Alta Pressão , Colorimetria , Concentração de Íons de Hidrogênio , Cinética , Cloreto de Sódio/análise
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