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2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 894-897, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34891434

RESUMO

Face recognition and related psychological phenomenon have been the subject of neurocognitive studies during last decades. More recently the problem of face identification is also addressed to test the possibility of finding markers on the electroencephalogram signals. To this end, this work presents an experimental study where Brain Computer Interface strategies were implemented to find features on the signals that could discriminate between culprit and innocent. The feature extraction block comprises time domain and frequency domain characteristics of single-trial signals. The classification block is based on a support vector machine and its performance for the best ranked features. The data analysis comprises the signals of a cohort of 28 participants.


Assuntos
Algoritmos , Interfaces Cérebro-Computador , Eletroencefalografia , Humanos , Máquina de Vetores de Suporte
3.
Sci Total Environ ; 636: 1553-1564, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29913616

RESUMO

Abamectin (ABA) toxicity in fish, amphibian and mammals was already proven, but its effect on birds is almost unknown. Thus, the aim of our study is to assess the impact of exposure to water with ABA for 40 days at predicted environmentally relevant concentrations on the behavior of female Japanese quails (Coturnix coturnix japonica). The three following experimental groups (n = 10 each) were set: "control", quails exposed to drinking water, without ABA, "EC1x" and "EC1000x" (0.31 mg a.i./L and 310.0 a.i./L, respectively; via commercial formulation Kraft® 36EC). The open field test showed anxiolytic response in birds exposed to ABA. These birds did not show locomotor changes or aggressive behavior in the aggressiveness test. Quails exposed to the pesticide did not react to the introduction of an object in the experimental box during the object recognition test, and it suggested perception deficit due to ABA. Moreover, these birds did not recognize the cat (Felix catus) and the vocalization of a hawk (Rupornis magnirostris) as potential predatory threats. These responses also suggest anti-predatory behavior deficit due to the pesticide. Thus, our study is pioneer in showing that water with ABA, at tested concentrations, influences the behavior of C. coturnix japonica, as well as in highlighting the potential impacts of this pesticide on this group of birds.


Assuntos
Comportamento Animal/efeitos dos fármacos , Coturnix/fisiologia , Ivermectina/análogos & derivados , Praguicidas/toxicidade , Animais , Gatos , Feminino , Ivermectina/toxicidade
4.
Plant Cell Rep ; 37(8): 1113-1125, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29796947

RESUMO

KEY MESSAGE: Regulatory sequences from the citrus constitutive genes cyclophilin (CsCYP), glyceraldehyde-3-phosphate dehydrogenase C2 (CsGAPC2), and elongation factor 1-alpha (CsEF1) were isolated, fused to the uidA gene, and qualitatively and quantitatively evaluated in transgenic sweet orange plants. The 5' upstream region of a gene (the promoter) is the most important component for the initiation and regulation of gene transcription of both native genes and transgenes in plants. The isolation and characterization of gene regulatory sequences are essential to the development of intragenic or cisgenic genetic manipulation strategies, which imply the use of genetic material from the same species or from closely related species. We describe herein the isolation and evaluation of the promoter sequence from three constitutively expressed citrus genes: cyclophilin (CsCYP), glyceraldehyde-3-phosphate dehydrogenase C2 (CsGAPC2), and elongation factor 1-alpha (CsEF1). The functionality of the promoters was confirmed by a histochemical GUS assay in leaves, stems, and roots of stably transformed citrus plants expressing the promoter-uidA construct. Lower uidA mRNA levels were detected when the transgene was under the control of citrus promoters as compared to the expression under the control of the CaMV35S promoter. The association of the uidA gene with the citrus-derived promoters resulted in mRNA levels of up to 60-41.8% of the value obtained with the construct containing CaMV35S driving the uidA gene. Moreover, a lower inter-individual variability in transgene expression was observed amongst the different transgenic lines, where gene constructs containing citrus-derived promoters were used. In silico analysis of the citrus-derived promoter sequences revealed that their activity may be controlled by several putative cis-regulatory elements. These citrus promoters will expand the availability of regulatory sequences for driving gene expression in citrus gene-modification programs.


Assuntos
Citrus sinensis/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Citrus sinensis/genética , Ciclofilinas/genética , Ciclofilinas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Regiões Promotoras Genéticas/genética , Regiões Promotoras Genéticas/fisiologia , RNA Mensageiro/genética
5.
Radiat Res ; 190(1): 37-44, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29693502

RESUMO

3'-Deoxy-3-[18F]fluorothymidine, or [18F]FLT, is a positron emission tomography (PET) tracer used in clinical studies for noninvasive assessment of proliferation activity in several types of cancer. Although the use of this PET tracer is expanding, to date, few studies concerning its dosimetry have been published. In this work, new [18F]FLT dosimetry estimates are determined for human and mice using Monte Carlo simulations. Modern voxelized male and female phantoms and [18F]FLT biokinetic data, both published by the ICRP, were used for simulations of human cases. For most human organs/tissues the absorbed doses were higher than those reported in ICRP Publication 128. An effective dose of 1.70E-02 mSv/MBq to the whole body was determined, which is 13.5% higher than the ICRP reference value. These new human dosimetry estimates obtained using more realistic human phantoms represent an advance in the knowledge of [18F]FLT dosimetry. In addition, mice biokinetic data were obtained experimentally. These data and a previously developed voxelized mouse phantom were used for simulations of animal cases. Concerning animal dosimetry, absorbed doses for organs/tissues ranged from 4.47 ± 0.75 to 155.74 ± 59.36 mGy/MBq. The obtained set of organ/tissue radiation doses for healthy Swiss mice is a useful tool for application in animal experiment design.


Assuntos
Didesoxinucleosídeos , Radiometria/instrumentação , Animais , Didesoxinucleosídeos/farmacocinética , Feminino , Humanos , Masculino , Camundongos , Imagens de Fantasmas , Distribuição Tecidual
6.
Scand J Med Sci Sports ; 28(3): 794-806, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28801950

RESUMO

It is recognized that stretching is an effective method to chronically increase the joint range of motion. However, the effects of stretching training on the muscle-tendon structural properties remain unclear. This systematic review with meta-analysis aimed to determine whether chronic stretching alter the muscle-tendon structural properties. Published papers regarding longitudinal stretching (static, dynamic and/or PNF) intervention (either randomized or not) in humans of any age and health status, with more than 2 weeks in duration and at least 2 sessions per week, were searched in PubMed, PEDro, ScienceDirect and ResearchGate databases. Structural or mechanical variables from joint (maximal tolerated passive torque or resistance to stretch) or muscle-tendon unit (muscle architecture, stiffness, extensibility, shear modulus, volume, thickness, cross-sectional area, and slack length) were extracted from those papers. A total of 26 studies were selected, with a duration ranging from 3 to 8 weeks, and an average total time under stretching of 1165 seconds per week. Small effects were seen for maximal tolerated passive torque, but trivial effects were seen for joint resistance to stretch, muscle architecture, muscle stiffness, and tendon stiffness. A large heterogeneity was seen for most of the variables. Stretching interventions with 3- to 8-week duration do not seem to change either the muscle or the tendon properties, although it increases the extensibility and tolerance to a greater tensile force. Adaptations to chronic stretching protocols shorter than 8 weeks seem to mostly occur at a sensory level.


Assuntos
Exercícios de Alongamento Muscular , Músculo Esquelético/fisiologia , Tendões/fisiologia , Adaptação Fisiológica , Elasticidade , Humanos , Ensaios Clínicos Controlados não Aleatórios como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Amplitude de Movimento Articular , Torque
7.
Scand J Med Sci Sports ; 27(11): 1384-1394, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27485683

RESUMO

We compared the effects of continuous exercise (CE) vs accumulated exercise (AE) training on CVD risk factors and heart of young male Wistar rats. The exercise training (ET) was performed in a swimming pool for 30-60 min/day, 5 days/week over 15 weeks. CE group performed the ET in a single long daily session (30-60 min), while AE group performed the ET at the same frequency, intensity, and duration of CE rats, but in three short bouts over the course of a day (10-20 min in three daily sessions). AE training was more efficient than CE in attenuating body and fat weight gain and inhibiting visceral adipocyte hypertrophy at the same food intake level. CE training was more efficient in improving systolic blood pressure, LDL/HDL cholesterol, and serum triglyceride. Both ET protocols increased heart function, decreased lipid peroxidation, and increased intracellular Hsp72 content in the heart. This work shows distinct beneficial effects of CE vs AE training suggesting that the prescription of one or other may be preferred to prevent the increase of a specific CVD risk factor.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Coração/fisiologia , Condicionamento Físico Animal/métodos , Animais , Pressão Sanguínea , Proteínas de Choque Térmico HSP72/metabolismo , Gordura Intra-Abdominal , Lipídeos/sangue , Masculino , Ratos Wistar , Fatores de Risco , Aumento de Peso
8.
J Phys Chem A ; 119(34): 9059-69, 2015 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-26244250

RESUMO

The electronic spectroscopy of isolated toluene in the gas phase has been investigated using high-resolution photoabsorption spectroscopy in the 4.0-10.8 eV energy range, with absolute cross-section measurements derived. We present the first set of ab initio calculations (vertical energies and oscillator strengths), which we use in the assignment of valence and Rydberg transitions of the toluene molecule. The spectrum reveals several new features not previously reported in the literature, with particular relevance to 7.989 and 8.958 eV, which are here tentatively assigned to the π*(17a') ← σ(15a') and 1π*(10a″) ← 1π(14a') transitions, respectively. The measured absolute photoabsorption cross sections have been used to calculate the photolysis lifetime of toluene in the upper stratosphere (20-50 km).


Assuntos
Elétrons , Teoria Quântica , Síncrotrons , Tolueno/química , Raios Ultravioleta , Absorção de Radiação , Atmosfera , Fotólise , Espectrofotometria Ultravioleta , Vácuo
9.
Toxicon ; 97: 64-74, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25701676

RESUMO

Scorpionism represents a serious public health problem resulting in the death of children and debilitated individuals. Scorpion sting treatment employs various strategies including the use of specific medicines such as antiserum, especially for patients with severe symptoms. In 1909 Charles Todd described the production of an antiserum against the venom of the scorpion Buthus quinquestriatus. Based on Todd's work, researchers worldwide began producing antiserum using the same approach i.e., immunization of horses with crude venom as antigen. Despite achieving satisfactory results using this approach, researchers in this field have developed alternative approaches for the production of scorpion antivenom serum. In this review, we describe the work published by experts in toxinology to the development of scorpion venom antiserum. Methods and results describing the use of specific antigens, detoxified venom or toxins, purified toxins and or venom fractions, native toxoids, recombinant toxins, synthetic peptides, monoclonal and recombinant antibodies, and alternative animal models are presented.


Assuntos
Antivenenos/biossíntese , Imunização/métodos , Modelos Animais , Picadas de Escorpião/tratamento farmacológico , Picadas de Escorpião/epidemiologia , Venenos de Escorpião/antagonistas & inibidores , Anticorpos Monoclonais/uso terapêutico , Antivenenos/história , Antivenenos/uso terapêutico , História do Século XIX , História do Século XX , História do Século XXI , Humanos , Proteínas Recombinantes/uso terapêutico , Venenos de Escorpião/química , Venenos de Escorpião/toxicidade , Especificidade da Espécie
10.
Toxicon ; 90: 45-55, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25091350

RESUMO

Tityus serrulatus is a Brazilian scorpion species with great medical significance. While the effects of neurotoxins have been extensively studied, little is known about the proteases expressed in the venom gland of this arthropod. In this study, clones from a T. serrulatus (Ts) venom gland cDNA library were selected according to homology to proteases. The sequences were aligned in the database and classified by homology. Similarity and identity analyses of the sequences were carried out, and a phylogenetic tree was constructed with the sequences of other proteases. These cDNA sequences correspond to ten different metalloproteases, named metalloserrulases (TsMS). TsMS 1-9 belong to the metzincin family, which has three domains: signal peptide, propeptide, and metalloprotease domain; while TsMS 10 belongs to the gluzincin family. The proteolytic activity of the venom was inferred from the cleavage of fibrinogen, and the residues recognized by the proteases were determined by cleavage of a tripeptide library using a fluorescence resonance energy transfer assay. The Ts venom showed proteolytic activity on fibrinogen and preferential cleavage close to the basic residues K and R. Its activity could be inhibited by EDTA, indicating that the venom from this scorpion predominantly consists of metalloproteases.


Assuntos
Metaloproteases/genética , Metaloproteases/toxicidade , Venenos de Escorpião/enzimologia , Sequência de Aminoácidos , Animais , DNA Complementar/genética , Fibrinogênio/metabolismo , Metaloproteases/química , Dados de Sequência Molecular , Filogenia , Escorpiões , Homologia de Sequência de Aminoácidos
11.
Ecotoxicol Environ Saf ; 107: 9-15, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24905691

RESUMO

The main objective of this study was to assess the environmental risk of chars derived from the pyrolysis of mixtures of pine, plastics, and scrap tires, by studying their leaching potential and ecotoxicity. Relationships between chemical composition and ecotoxicity were established to identify contaminants responsible for toxicity. Since metallic contaminants were the focus of the present study, an EDTA washing step was applied to the chars to selectively remove metals that can be responsible for the observed toxicity. The results indicated that the introduction of biomass to the pyrolysis feedstock enhanced the acidity of chars and promote the mobilisation of inorganic compounds. Chars resulting from the pyrolysis of blends of pine and plastics did not produce ecotoxic eluates. A relationship between zinc concentrations in eluates and their ecotoxicity was found for chars obtained from mixtures with tires. A significant reduction in ecotoxicity was found when the chars were treated with EDTA, which was due to a significant reduction in zinc in chars after EDTA washing.


Assuntos
Carvão Vegetal/química , Biomassa , Carvão Vegetal/toxicidade , Ácido Edético/química , Agricultura Florestal , Metais/isolamento & purificação , Pinus , Plásticos , Medição de Risco , Resíduos
12.
Arq Bras Cardiol ; 101(3 Suppl 3): 1-95, 2013 09.
Artigo em Português | MEDLINE | ID: mdl-24196826
13.
Water Sci Technol ; 68(9): 2019-27, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24225103

RESUMO

Removal batch assays of phosphates from a synthetic wastewater (SWW) and a pulp and paper mill wastewater (PPWW) with two forestry biomass ashes were performed. The supernatants were not only chemically characterized but also the ecotoxicity was determined using two organisms: Vibrio fischeri and Artemia franciscana. The addition of fly ash and bottom ash to the SWW in solid/liquid (S/L) ratios of 3.35 and 9.05 g L(-1), respectively, achieved removal percentages of phosphates >97% for both ashes. The addition of fly ash and bottom ash to the PPWW in S/L ratios of 34.45 and 46.59 g L(-1), respectively, yield removal percentages of phosphates >90% for both ashes. According to the results of the Langmuir and Freundlich isotherms, the removal of phosphates from the SWW was mainly explained by surface removal mechanisms, while the removal from the PPWW was partially explained by multi-layer mechanisms. The supernatants resulting from the treatment of SWW and PPWW with both biomass ashes did not present acute ecotoxicity.


Assuntos
Cinza de Carvão/toxicidade , Fosfatos/metabolismo , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/metabolismo , Aliivibrio fischeri/efeitos dos fármacos , Animais , Artemia/efeitos dos fármacos , Indústria Editorial , Cinza de Carvão/metabolismo , Agricultura Florestal , Papel , Fosfatos/química , Águas Residuárias/análise , Poluentes Químicos da Água/química
14.
Toxicon ; 72: 102-12, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23792453

RESUMO

Members of the spider genus Lasiodora are widely distributed in Brazil, where they are commonly known as caranguejeiras. Lasiodora spider venom is slightly harmful to humans. The bite of this spider causes local pain, edema and erythema. However, Lasiodora sp. spider venom may be a source of important pharmacological tools. Our research group has described previously that Lasiodora sp. venom produces bradycardia in the isolated rat heart. In the present work, we sought to evaluate the vascular effect of Lasiodora sp. venom and to isolate the vasoactive compounds from the venom. The results showed that Lasiodora spider venom induced a concentration-dependent vasodilation in rat aortic rings, which was dependent on the presence of a functional endothelium and abolished by the nitric oxide synthase (NOS) inhibitor L-NAME. Western blot experiments revealed that the venom also increased endothelial NOS function by increasing phosphorylation of the Ser¹¹77 residue. Assay-directed fractionation isolated a vasoactive fraction from Lasiodora sp. venom. Mass spectrometry (MS) and nuclear magnetic resonance (NMR) assays identified a mixture of two compounds: adenosine diphosphate (ADP, approximately 90%) and adenosine monophosphate (AMP, approximately 10%). The vasodilator effects of Lasiodora sp. whole venom, as well as ADP, were significantly inhibited by suramin, which is a purinergic P2-receptor antagonist. Therefore, the results of the present work indicate that ADP is a main vasodilator component of Lasiodora sp. spider venom.


Assuntos
Difosfato de Adenosina/farmacologia , Venenos de Aranha/química , Aranhas/química , Vasodilatadores/farmacologia , Difosfato de Adenosina/química , Monofosfato de Adenosina/química , Animais , Western Blotting , Fracionamento Químico , Endotélio/efeitos dos fármacos , Técnicas In Vitro , Espectrometria de Massas , NG-Nitroarginina Metil Éster/metabolismo , Óxido Nítrico Sintase/metabolismo , Ressonância Magnética Nuclear Biomolecular , Fosforilação/efeitos dos fármacos , Ratos , Suramina/química , Vasodilatação/efeitos dos fármacos , Vasodilatadores/química
15.
J Hazard Mater ; 219-220: 196-202, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22520075

RESUMO

The present work aims to perform a multistep upgrading of chars obtained in the co-pyrolysis of PE, PP and PS plastic wastes, pine biomass and used tires. The quality of the upgraded chars was evaluated by measuring some of their physico-chemical properties in order to assess their valorisation as adsorbents' precursors. The crude chars were submitted to a sequential solvent extraction with organic solvents of increasing polarity (hexane, mixture 1:1 v/v hexane:acetone and acetone) followed by an acidic demineralization procedure with 1M HCl solution. The results obtained showed that the upgrading treatment allow the recovery of 63-81% of the pyrolysis oils trapped in the crude chars and a reduction in the char's ash content in the range of 64-86%. The textural and adsorption properties of the upgraded chars were evaluated and the results indicate that the chars are mainly mesoporous and macroporous materials, with adsorption capacities in the range of 3.59-22.2 mg/g for the methylene blue dye. The upgrading treatment allowed to obtain carbonaceous materials with quality to be reused as adsorbents or as precursors for activated carbon.


Assuntos
Temperatura Alta , Gerenciamento de Resíduos/métodos , Adsorção , Biomassa
16.
J Hazard Mater ; 207-208: 28-35, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21899951

RESUMO

The present work is devoted to the study of the decontamination of chars obtained in the co-pyrolysis of plastics, biomass and tyre wastes. The chars were extracted with several organic solvents of different polarities either individually or in sequence. The ability of each selected extractant to remove toxic pollutants was evaluated by comparing the extraction yields and by characterizing the crude extracts with a combination of chemical analysis and toxicity bioassays. Also, the mineral composition of the treated and non-treated chars was assessed. The results obtained in this study indicate that hexane is the more efficient extraction solvent to be used in the organic decontamination of chars obtained in the co-pyrolysis of plastics, tyres and biomass. A sequential extraction with solvents of increasing polarity can provide a better decontamination of the raw pyrolysis char than any individual extraction. The compounds removed from the char during the decontamination process are mainly aliphatic hydrocarbons and aromatic hydrocarbons, therefore a material that may be upgraded to be used as a fuel and/or as raw material for the organic chemical industry.


Assuntos
Incineração , Resíduos Industriais , Bioensaio , Biomassa , Cromatografia Gasosa-Espectrometria de Massas , Gerenciamento de Resíduos
17.
Chemosphere ; 79(11): 1026-32, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20416925

RESUMO

Dispersive liquid-liquid microextraction (DLLME) coupled with gas chromatography-mass spectrometry (GC-MS) was applied for the determination of 11 alkylphenols in eluates of chars produced in the co-pyrolysis of different wastes. The optimized DLLME procedure, 4 mL of sample solution, 15 microL of trichloroethylene as extraction solvent, 1 mL of acetone as dispersion solvent and addition of 15% (w/v) of NaCl, was validated. Under the optimum conditions, the enrichment factors were in the range of 82-180. Calibration curves were constructed for each analyte in pure water in the concentration range of 0.5-8 microg/L with correlation coefficients higher than 0.999. The limits of detection were between 0.07 and 0.17 microg/L. The repeatability of the method was evaluated using water samples fortified with the analyte mixture at two concentration levels: the relative standard deviation (RSD) values were between 3.7% and 8.0% for a concentration of 0.5 microg/L, and between 4.2% and 6.4% for a concentration of 3 microg/L. The recoveries of the analytes evaluated by fortification of real eluate samples were in the range of 67.9-97.9% for eluate 1 (obtained from a decontaminated char) and in the range of 61.9-101.4% for eluate 2 (obtained from the untreated char). o-Methylphenol presented low recoveries for both eluates showing a possible matrix effect. The results obtained show that this method is adequate for the determination of alkylphenols in environmental aqueous samples and presents itself as a fast and inexpensive technique, using minor amounts of organic solvents.


Assuntos
Poluentes Ambientais/análise , Fenol/análise , Fracionamento Químico , Poluentes Ambientais/química , Poluentes Ambientais/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Fenol/química , Fenol/isolamento & purificação , Reprodutibilidade dos Testes , Cloreto de Sódio/química , Solventes/química
18.
Waste Manag ; 30(4): 628-35, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19932606

RESUMO

Char residues produced in the co-pyrolysis of different wastes (plastics, pine biomass and used tyres) were characterized using chemical and toxicity assays. One part of the solid chars was submitted to extraction with dichloromethane (DCM) in order to reduce the toxicity of the char residues by removing organic contaminants. The different volatility fractions present in the extracted char (Char A) and in the raw char (Char B) were determined by progressive weight loss combustion. A selected group of heavy metals (Cd, Pb, Zn, Cu, Hg and As) was determined in both chars. The chars were subjected to the leaching test ISO/TS 21268 - 2, 2007 and the resulting eluates were further characterized by determining a group of inorganic parameters (pH, conductivity, Cd, Pb, Zn, Cu, Hg and As contents) and the concentrations of several organic contaminants (volatile aromatic hydrocarbons and alkyl phenols). An ecotoxicological characterization was also performed by using the bio-indicator Vibrio fischeri. The chemical and ecotoxicological results were analyzed according to the Council Decision 2003/33/CE and the criteria on the evaluation methods of waste ecotoxicity (CEMWE). The results obtained in this work indicated that the extraction with DCM is an effective method for the removal of organic contaminants of high to medium volatility from pyrolysis solid residues, thus decreasing their toxicity potential. Zn can be leached from the chars even after the DCM extraction treatment and can contribute to the ecotoxicity of the eluates obtained from chars. Both chars (treated and non treated with DCM) were classified as hazardous and ecotoxic wastes.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Ecotoxicologia/métodos , Temperatura Alta , Incineração , Eliminação de Resíduos , Resíduos/efeitos adversos , Resíduos/análise , Aliivibrio fischeri/crescimento & desenvolvimento , Aliivibrio fischeri/metabolismo , Animais , Biomassa , Metais Pesados/análise , Metais Pesados/toxicidade , Cloreto de Metileno/análise , Cloreto de Metileno/química , Compostos Orgânicos/análise , Compostos Orgânicos/toxicidade , Pinus , Plásticos , Borracha , Testes de Toxicidade
19.
Talanta ; 80(1): 104-8, 2009 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19782198

RESUMO

A method for the determination of 15 aromatic hydrocarbons in eluates from solid residues produced during the co-pyrolysis of plastics and pine biomass was developed. In a first step, several sampling techniques (headspace solid phase microextraction (HS-SPME), static headspace sampling (HS), and dispersive liquid-liquid microextraction (DLLME) were compared in order to evaluate their sensitivity towards these analytes. HS-SPME and HS sampling had the better performance, but DLLME was itself as a technique able to extract volatiles with a significant enrichment factor. HS sampling coupled with GC-MS was chosen for method validation for the analytes tested. Calibration curves were constructed for each analyte with correlation coefficients higher than 0.999. The limits of detection were in the range of 0.66-37.85 ng/L. The precision of the HS method was evaluated and good repeatability was achieved with relative standard deviations of 4.8-13.2%. The recoveries of the analytes were evaluated by analysing fortified real eluate samples and were in the range of 60.6-113.9%. The validated method was applied in real eluate samples. Benzene, toluene, ethylbenzene and xylenes (BTEX) were the compounds in higher concentrations. The DLLME technique coupled with GC-MS was used to investigate the presence of less volatile contaminants in eluate samples. This analysis revealed the presence of significant amounts of alkyl phenols and other aromatic compounds with appreciable water solubility.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocarbonetos Aromáticos/análise , Benzeno/análise , Benzeno/isolamento & purificação , Derivados de Benzeno/análise , Derivados de Benzeno/isolamento & purificação , Calibragem , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Hidrocarbonetos Aromáticos/isolamento & purificação , Reprodutibilidade dos Testes , Microextração em Fase Sólida , Tolueno/análise , Tolueno/isolamento & purificação , Xilenos/análise , Xilenos/isolamento & purificação
20.
Neurology ; 72(15): 1345-51, 2009 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-19365056

RESUMO

OBJECTIVE: Our purpose was to develop a geographically localized, multi-institution strategy for improving enrolment in a trial of secondary stroke prevention. METHODS: We invited 11 Connecticut hospitals to participate in a project named the Local Identification and Outreach Network (LION). Each hospital provided the names of patients with stroke or TIA, identified from electronic admission or discharge logs, to researchers at a central coordinating center. After obtaining permission from personal physicians, researchers contacted each patient to describe the study, screen for eligibility, and set up a home visit for consent. Researchers traveled throughout the state to enroll and follow participants. Outside the LION, investigators identified trial participants using conventional recruitment strategies. We compared recruitment success for the LION and other sites using data from January 1, 2005, through June 30, 2007. RESULTS: The average monthly randomization rate from the LION was 4.0 participants, compared with 0.46 at 104 other Insulin Resistance Intervention after Stroke (IRIS) sites. The LION randomized on average 1.52/1,000 beds/month, compared with 0.76/1,000 beds/month at other IRIS sites (p = 0.03). The average cost to randomize and follow one participant was $8,697 for the LION, compared with $7,198 for other sites. CONCLUSION: A geographically based network of institutions, served by a central coordinating center, randomized substantially more patients per month compared with sites outside of the network. The high enrollment rate was a result of surveillance at multiple institutions and greater productivity at each institution. Although the cost per patient was higher for the network, compared with nonnetwork sites, cost savings could result from more rapid completion of research.


Assuntos
Ensaios Clínicos como Assunto/métodos , Doenças do Sistema Nervoso/terapia , Neurologia/organização & administração , Seleção de Pacientes , Connecticut , Hospitais Comunitários , Humanos , Consentimento Livre e Esclarecido , Resistência à Insulina , Ataque Isquêmico Transitório/prevenção & controle , Estudos Multicêntricos como Assunto , Distribuição Aleatória , Acidente Vascular Cerebral/prevenção & controle
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