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1.
Environ Pollut ; 344: 123338, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38218543

RESUMO

Santa Luzia, an uninhabited island in the archipelago of Cabo Verde, serves as a natural laboratory and important nesting site for loggerhead turtles Carettacaretta. The island constitutes an Integral Natural Reserve and a Marine Protected Area. We assessed marine litter accumulation on sandy beaches of the island and analysed their spatial patterns using two sampling methods: at a fine scale, sand samples from 1 × 1 m squares were collected, identifying debris larger than 1 mm; at a coarse scale, drone surveys were conducted to identify visible marine debris (>25 mm) in aerial images. We sampled six points on three beaches of the island: Achados (three points), Francisca (two points) and Palmo Tostão (one point). Then, we modelled the abundance of marine debris using topographical variables as explanatory factors, derived from digital surface models (DSM). Our findings reveal that the island is a significant repository for marine litter (>84% composed of plastics), with up to 917 plastic items per m2 in the sand samples and a maximum of 38 macro-debris items per m2 in the drone surveys. Plastic fragments dominate, followed by plastic pellets (at the fine-scale approach) and fishing materials (at the coarse-scale approach). We observed that north-facing, higher-elevation beaches accumulate more large marine litter, while slope and elevation affect their spatial distribution within the beach. Achados Beach faces severe marine debris pollution challenges, and the upcoming climate changes could exacerbate this problem.


Assuntos
Areia , Resíduos , Resíduos/análise , Cabo Verde , Plásticos/análise , Praias , Monitoramento Ambiental/métodos
2.
Braz. J. Pharm. Sci. (Online) ; 58: e19587, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1384015

RESUMO

This work aims to develop analytical methods using high-performance liquid chromatography with a diode array detector (HPLC-DAD) for analysis and quantification of avermectins (AVMs) and milbemycins (MBMs) in bulk samples. First, the methods were optimized and some parameters such as temperature, flow rate, injection volume and mobile phase with different proportions of solvents were evaluated. The best chromatographic conditions were obtained using the Phenomenex® C18 (150 × 4.60 mm, 5 µm) column at a temperature of 20 °C, flow rate of 1.2 mL min-1, injection volume of 20 µL, and detection at 250 nm. Acetonitrile: ultrapure water (87: 13, v/v) was used as mobile phase for moxidectin and eprinomectin, and acetonitrile: methanol: ultrapure water (53: 35: 12, v/v/v) for abamectin and ivermectin. Under these conditions satisfactory results were obtained, with appropriate limits of detection and quantification, acceptable linearity, precision, accuracy, and robustness. These methods satisfy the need for analytical methods for the multi-determination of MBMs and the B1a and B1b forms of AVMs by HPLC-DAD, which can be considered simple, effective, innovative and should aid in the development of the fiel


Assuntos
Métodos de Análise Laboratorial e de Campo , Cromatografia Líquida de Alta Pressão/métodos , Estudo de Validação , Controle de Qualidade , Ivermectina/efeitos adversos , Métodos de Análise Laboratorial e de Campo , Inseminação Artificial Heteróloga/classificação
4.
Food Chem ; 345: 128745, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33302105

RESUMO

In this work, we report the synthesis of a mesoporous molecularly imprinted polymer on the surface of silica nanoparticles (core@mMIP) to be applied as adsorbent in microextraction by packed sorbent (MEPS) for selective determination of pesticides in apple juice. The core@mMIP was properly characterized, showing good adhesion of the polymer to the silica core. The best extraction conditions were: 200 µL of ultrapure water as washing solvent, 150 µL of acetonitrile as eluent, 100 µL of sample at pH 2.5, five draw-eject cycles and 8 mg of adsorbent. Thereby, recoveries of 96.12 ± 1.05%, 76.88 ± 6.18% and 76.18 ± 5.57% were obtained for pyriproxyfen (PPX), deltamethrin (DTM) and etofenprox (ETF), respectively. After validation, the method presented linearity in the range of 0.02-10 µg mL-1 (r > 0.99), limit of detection of 0.005 µg mL-1, satisfactory selectivity, and proper precision and accuracy. The method was successfully applied real samples of processed and fresh apple juice.


Assuntos
Análise de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Malus/química , Nanopartículas/química , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/isolamento & purificação , Dióxido de Silício/química , Adsorção , Contaminação de Alimentos/análise , Polímeros Molecularmente Impressos/química , Porosidade , Solventes/química , Água/química
5.
Electrophoresis ; 39(20): 2581-2589, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29772601

RESUMO

In this work a hollow mesoporous structured molecularly imprinted polymer was synthetized and used as adsorbent in pipette-tip solid-phase extraction for the determination of lamivudine (3TC), zidovudine (AZT) and efavirenz (EFZ) from plasma of human immunodeficiency virus (HIV) infected patients by high-performance liquid chromatography (HPLC). All parameters that influence the recovery of the pipette tip based on hollow mesoporous molecularly imprinted polymer solid-phase extraction (PT-HM-MIP-SPE) method were systematically studied and discussed in detail. The adsorbent material was prepared using methacrylic acid and 4-vinylpyridine as functional monomers, ethylene glycol dimethacrylate as crosslinker, acetonitrile as solvent, 4,4'-azobis(4-cyanovaleric acid) as radical initiator, benzalkonium chloride as surfactant, 3TC, and AZT as templates. The simultaneous separation of 3TC, AZT and EFZ by HPLC-UV was performed using a Gemini C18 Phenomenex® column (250 mm × 4.6 mm, 5 µm) and mobile phase consisting of acetonitrile: water pH 3.2 (68:32, v/v), flow rate of 1.0 mL/min and λ = 260 nm. The method was linear over the concentration range from 0.25 to 10 µg/mL for 3TC and EFZ, and 0.05 to 2.0 µg mL-1 for AZT, with correlation coefficients larger than 0.99 for all analytes. Recovery ± relative standard deviations (RSDs %) were 41.99 ± 2.38%, 82.29 ± 1.63%, and 83.72 ± 7.52% for 3TC, AZT, and EFZ, respectively. The RSDs and relative errors (REs) were lower than 15% for intra and interday assays. The method has been successfully applied for monitoring HIV-infected patients outside the therapeutic dosage.


Assuntos
Antirretrovirais/sangue , Infecções por HIV/tratamento farmacológico , Impressão Molecular/métodos , Extração em Fase Sólida/métodos , Antirretrovirais/isolamento & purificação , Antirretrovirais/uso terapêutico , Cromatografia Líquida de Alta Pressão , Humanos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
6.
Artigo em Português | LILACS, Index Psicologia - Periódicos | ID: biblio-985842

RESUMO

O presente trabalho teve por objetivo avaliar possíveis fatores associados com a depressão pós-parto (DPP), como o uso de substâncias e o suporte psicossocial em uma amostra de 102 mulheres em situação de vulnerabilidade social. O estudo foi realizado com puérperas que residiam provisoriamente no alojamento de um Hospital Maternidade público. Aproximadamente 20% das puérperas apresentaram critérios para a DPP além de um padrão de uso de álcool e maconha superior àquelas que não tinham o transtorno. Observou-se também associação entre violência, falta de suporte psicológico e apoio familiar com a DPP. Observou-se uma associação entre a DPP com outras comorbidades de modo que algumas variáveis estudadas possam estar envolvidas na etiologia e manutenção deste transtorno.


This study aimed to evaluate possible factors associated with postpartum depression syndrome (PDD), as the substance abuse and psychosocial support in a sample of 102 women in a social vulnerability condition. The study was conducted with mothers who were residents in specific hospital's lodging. Almost 20% of mothers showed symptoms to PDD as well as abusive alcohol and marijuana consumption compared with those who did not have PDD. Besides, it was observed an association between lack of psychological and familiar support with PDD. PDD it seems to be associated with other comorbidities so that some of these variables can be linked on the etiology and maintenance of PDD.


Este estudo tuvo como objectivo evaluar possibles factores associados con la Depresión Posparto (DPP) como el uso de substancias y apoio psicossocial em 102 mujeres em situación de vulnerabilidad social. El estúdio se realizó com las madres residentes transitórias em la vivienda de un Hospital Maternidad. Aproximadamente 20% de las madres presentaron criterios para el DPP, así como un de consumo de alcohol y marihuana superior a aquellas que no tienen el trastorno. También fue observada uma asociación entre la violencia, falta de apoyo psicológico y de la familia con el DPP. El DPP parece estar asociada con otras enfermedades concomitantes por lo que algunas variables pueden estar implicados en la etiología y el mantenimiento de este trastorno.


Assuntos
Humanos , Feminino , Transtornos Relacionados ao Uso de Substâncias , Vulnerabilidade Social , Transtorno Depressivo , Período Pós-Parto
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