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1.
Nanotechnology ; 30(47): 475703, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31426031

RESUMO

Herein, we present an electrochemical functionalization strategy for high quality single-layer and multilayer chemical vapor deposited (CVD) graphene directly on a Si/SiO2 chip facilitating electronic interfacing. This method avoids oxidation and tearing of graphene basal planes. We demonstrate effective functionalization by D-(+)-biotin (Bio), 4-(phenyldiazenyl)-aniline (Dz), and gallic acid (Gall) using cyclic voltammetry. Raman spectroscopy and XPS are used to demonstrate effective functionalization. In order to evaluate the effect of the electrochemical functionalization on graphene properties, DC electrical conductivity, XPS, mobility, and carrier density analysis are presented. We show that this functionalization strategy does not degrade graphene mobility (103 cm2 V-1s-1). After functionalization we observe a rise in Fermi level of ∼0.06 eV. In addition, we prove sensing capabilities with a CVD graphene monolayer on the biotin/avidin system by electrical resistance measurements and electrochemical impedance spectroscopy reaching a detection of 2.5 ng ml-1. This paper demonstrates an effective strategy to functionalize high quality CVD graphene on a chip compatible with an electronic interface readout.

2.
Molecules ; 24(9)2019 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-31060217

RESUMO

This paper presents the synthesis and evaluation of physicochemical behavior of a new series of N-alkyl-bis-o-aminobenzamides (BOABs) in aqueous solution. The study was targeted to the complexing capacity of five metal ions (Fe2+, Cu2+, Cd2+, Hg2+ and Pb2+) of environmental concern as the medullar principle of a liquid phase sensor for its application in the determination of these metal ions due to its versatility of use. Molecular fluorescence, UV-visible and Zeta potential were measured for five BOABs and the effect of alkyl groups with different central chain length (n = 3, 4, 6, 8 and 10) on physicochemical performance determined. The results have shown that these derivatives present higher sensibility and selectivity for Cu2+ even in the presence of the other metal ions. An additional application test was done adding a pectin (0.1 wt %) solution to the BOAB-Cu+2 complex to obtain a precipitate (flocs) as a potential selective separation process of Cu from aqueous solution. The solid was then lyophilized and analyzed by SEM-EDS, the images showed spheric forms containing Cu+2 with diameter of approximately of 8 µm and 30 wt %.


Assuntos
Benzamidas/síntese química , Corantes Fluorescentes/síntese química , Metais/química , Benzamidas/química , Cádmio/química , Cobre/química , Cristalografia por Raios X , Corantes Fluorescentes/química , Ferro/química , Chumbo/química , Mercúrio/química , Espectrometria de Fluorescência
3.
RSC Adv ; 13(51): 36023-36034, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38090070

RESUMO

Dye-sensitized solar cells (DSSCs) are an increasingly attractive alternative energy source because of their low cost. Therefore, researchers have intensified efforts over the past decade to increase their energy conversion efficiency by employing new materials in each DSSC component. The present research focuses on synthesizing electrospun nanofibers as a potential new material as a counter electrode in DSSCs. Two Ru(ii) half sandwich 1,10 phenanthroline (phen) Ru-1 and 5-amino- phen Ru-2 complexes were prepared for its functionalization. As a deposition medium, poly(caprolactone) (PCL) dissolved in chloroform was used. Different Ru(ii) complex concentrations were made at 0.1% wt., 0.5% wt., and 1% wt. Thermal characterization studies using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were conducted to evaluate the behavior and weight loss of the samples with temperature variations. Fourier transform infrared spectroscopy (FTIR) measurements were taken to observe the bond interaction of the ruthenium complexes and the PCL. Finally, scanning electron microscopy (SEM) was used to structurally and morphologically evaluate the fiber distribution and porosity. These fibers have a homogeneous morphology, without bulbs, but with evident solid inlays on the surface, with fibers between ∼0.58 to 2.47 µm and percentages of porosity ∼45%. TGA and DSC thermograms show minor temperature variations that demonstrate the incorporation of the Ru(ii) complexes into the fiber. Furthermore, the melting and degradation temperature of the fibers is suitable for use in a DSSC approach. The incorporation of the ruthenium compounds into PCL fibers, along with the addition of the NH2 group into complex Ru-2, resulted in a higher current density for both anodic and cathodic peaks in Cyclic Voltammetry (CV). It is noteworthy that from I-V curves, PCL-Ru2 1% fibers demonstrated a conductivity of 0.461 µS cm-1, which is comparable to other PCL fibers carrying a higher metal load. Future studies will delve into the mechanical properties of these fibers to highlight their potential for application in this field.

4.
J Addict Med ; 16(4): 447-453, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34775441

RESUMO

OBJECTIVES: Low-threshold buprenorphine treatment aims to reduce barriers to evidence-based opioid use disorder treatment. We aimed to describe the treatment philosophy, practices, and outcomes of a low-threshold syringe services program (SSP)-based buprenorphine program developed through an SSP-academic medical center partnership. METHODS: We included all SSP participants who received 1 or more buprenorphine prescription from Feb 5, 2019 to October 9, 2020. We collected data on patient characteristics, substance use, buprenorphine prescriptions, and urine drug tests (UDTs). We evaluated buprenorphine treatment retention using prescription data and buprenorphine adherence using UDTs. We used 2 retention definitions: (1) percentage of patients with buprenorphine prescriptions at 30, 90, and 180 days; and (2) total percentage of days "covered" with buprenorphine prescriptions through 180 days. RESULTS: One-hundred and eighteen patients received 1 or more buprenorphine prescriptions. Patients were largely middle-aged (mean age 44, standard deviation 11), male (68%), Hispanic (31%) or Non-Hispanic Black (32%), with heroin (90%) and crack/cocaine (62%) use, and injection drug use (59%). Retention was 62%, 43%, and 31% at 30, 90, and 180 days, respectively. The median percentage of days covered with buprenorphine prescriptions through 180 days was 43% (interquartile range 8%-92%). Of the 82 patients who completed 2 or more UDTs, the median percentage of buprenorphine-positive UDTs was 71% (interquartile range 40%-100%). CONCLUSIONS: In an SSP-based low-threshold buprenorphine treatment program, approximately one-third of patients continued buprenorphine treatment for 180 days or more, and buprenorphine adherence was high. SSPs can be a pathway to buprenorphine treatment for patients at high risk for opioid-related harms.


Assuntos
Buprenorfina , Transtornos Relacionados ao Uso de Opioides , Adulto , Analgésicos Opioides/uso terapêutico , Buprenorfina/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Tratamento de Substituição de Opiáceos , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Desenvolvimento de Programas , Seringas
5.
Nanomaterials (Basel) ; 11(8)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34443812

RESUMO

In this work, the Förster resonance energy transfer (FRET) between carbon dots (CDs) as energy donors and riboflavin (RF) as an energy acceptor was optimized and the main parameters that characterize the FRET process were determined. The results were successfully applied in the development of an ultrasensitive ratiometric fluorescent sensor for the selective and sensitive determination of RF in different beverages. Water-soluble CDs with a high quantum yield (54%) were synthesized by a facile and direct microwave-assisted technique. The CDs were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), Zeta potential, and UV-visible and molecular fluorescence spectroscopy. The study of the FRET process at two donor concentrations showed that the energy transfer efficiency decreases as the donor concentration increases, confirming its dependence on the acceptor:donor ratio in nanoparticle-based systems. The results show the importance of optimizing the FRET process conditions to improve the corresponding output signal. The variation in the ratiometric signal with the concentration of RF showed linearity in a concentration range of 0 to 11 µM with R2 = 0.9973 and a detection limit of 0.025 µM. The developed nanosensor showed good selectivity over other possible types of interference. The sensor was then applied for the determination of RF in beverage samples using the standard addition method with recoveries between 96% and 106%. Preliminary cytocompatibility tests carried out with breast cancer cells (MDA-MB-231) revealed the nanosensor to be cytocompatible in its working concentration regime, even after long incubation times with cells. Altogether, the developed RF determination method was found to be fast, low-cost, highly sensitive, and selective and can be extended to other samples of interest in the biological and food sectors. Moreover, thanks to its long-lasting cytocompatibility, the developed platform can also be envisaged for other applications of biological interest, such as intracellular sensing and staining for live cell microscopy.

6.
Open Forum Infect Dis ; 7(8): ofaa290, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32818140

RESUMO

This study evaluated health outcomes among people who inject drugs who are infected with hepatitis C virus using an artificial intelligence platform. Mean (SD) cumulative adherence (visual confirmation of administration) was 91.3% (10.5%). Most subjects (88.2%) achieved ≥80% adherence to treatment, and 88.2% (15 of 17) achieved a sustained virologic response.

7.
J Appl Biomater Funct Mater ; 17(1): 2280800018817463, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30803286

RESUMO

An approach to solve the limitations of autologous bone grafting procedures in bone injury treatment is to develop bioactive coatings in the implantation system. The objective of this work is to compare the temperature effect on the stability of hydroxyapatite, graphene, and collagen colloidal suspensions to be used as biocompatible and bioactive coatings on a carbon fiber composite surface. Synthesized hydroxyapatite was assessed by X-ray diffraction. Zeta potential at different temperatures was evaluated. Specimens were characterized using scanning electron microscopy and Raman analysis. The results showed that the best hydroxyapatite/graphene ratio was 85/15, while those of the hydroxyapatite/collagen mixtures were 85/15. A hydroxyapatite/graphene/collagen mixture was synthesized based on these results.


Assuntos
Durapatita/síntese química , Colágeno/química , Durapatita/química , Eletrodos , Eletroforese , Grafite/química , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Análise Espectral Raman , Difração de Raios X
8.
Nanoscale ; 11(6): 2829-2839, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30676594

RESUMO

Herein, a series of N-doped carbon nanotube (CNx) samples were obtained by modifying the synthesis temperature. Consequently, the proportion of graphitic nitrogen (Ngraph) in the samples was systematically increased as a function of temperature. This allowed evaluation of the role of the CNx graphitic nitrogen in the oxygen reduction reaction (ORR). A correlation between the Ngraph content and the ORR onset potential was observed, which shifted to more positive potentials with an increase in kinetic current density (jk); this showed that Ngraph played a significant catalytic role in the ORR. The samples with high Ngraph content favored the two-electron pathway for the ORR not only in basic media (pH = 13) but also in neutral media (pH = 7), representing an attractive alternative for wastewater remediation through the on-site generation of H2O2. The energetic calculations showed that the formation of H2O2 must be favorable in the presence of graphitic nitrogen sites. Finally, the performance of the buckypaper arrangement was evaluated, and the CNx buckypaper showed a higher cathodic current peak as compared to CNx traditional ink dispersions. Overall, this study not only sheds light on the role of Ngraph in the ORR, but also demonstrates that CNx buckypaper is an efficient 3D electrode for electrocatalytic applications.

9.
J Hazard Mater ; 335: 18-27, 2017 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-28414945

RESUMO

In this paper nonstoichiometric interbiopolyelectrolyte green complexes (NIBPEGCs) were prepared using chitosan (Ch), alginate (AG) and poly(acrylic acid)(PAA). They are proposed as innovative formulations (polyelectrolytes and chelating agents) suitable for the elimination heavy metals contained in wastewater. This application may represent an integral solution for industries rejecting solid and aqueous metallic materials; however, it has not been previously reported. NIBPEGCs physicochemical performance was evaluated based on pH, particle size, surface charge, isoelectric point, dose, coagulation-flocculation kinetics and chemical affinity with seven metal ions. The experimental results showed that NIBPEGCs composed by AG/Ch and PAA/Chitosan have all the three complementary functions: chemical affinity, electrostatic interaction and particle entrapment anticipating more simple operation units to remove heavy metals. Complexes of AG/Ch (negative) were higher performance in removing heavy metals, with a dose window (150-180mg/L), lower dose of 410mg/L PAA/Ch (negative). Investigation of chelating performances of NIBPEGCs show that the efficiency of metal removal is: Ca˃Cr˃Cu˃Pb˃Ni˃Zn˃Cd. Transmittance vs time profiles, metals and zeta potential analysis showed that chelation capacity is the crucial factor to ensure metallic species removal, followed by physical entrapment of the metallic colloids. Integrating all presented results allow to sustain the development of excellent metals removal formulations.


Assuntos
Quelantes/química , Indústria Química , Metais Pesados/isolamento & purificação , Polieletrólitos/química , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Coloides , Floculação , Metais Pesados/química , Poluentes Químicos da Água/química
10.
Environ Sci Pollut Res Int ; 21(14): 8573-84, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24671400

RESUMO

Dairy wastewater is characterized by a high content of hardly biodegradable dissolved, colloidal, and suspended organic matter. This work firstly investigates the performance of two individual electrochemical treatments, namely electrocoagulation (EC) and electro-oxidation (EO), in order to finally assess the mineralization ability of a sequential EC/EO process. EC with an Al anode was employed as a primary pretreatment for the conditioning of 800 mL of wastewater. A complete reduction of turbidity, as well as 90 and 81% of chemical oxygen demand (COD) and total organic carbon (TOC) removal, respectively, were achieved after 120 min of EC at 9.09 mA cm(-2). For EO, two kinds of dimensionally stable anodes (DSA) electrodes (Ti/IrO2-Ta2O5 and Ti/IrO2-SnO2-Sb2O5) were prepared by the Pechini method, obtaining homogeneous coatings with uniform composition and high roughness. The (·)OH formed at the DSA surface from H2O oxidation were not detected by electron spin resonance. However, their indirect determination by means of H2O2 measurements revealed that Ti/IrO2-SnO2-Sb2O5 is able to produce partially physisorbed radicals. Since the characterization of the wastewater revealed the presence of indole derivatives, preliminary bulk electrolyses were done in ultrapure water containing 1 mM indole in sulfate and/or chloride media. The performance of EO with the Ti/IrO2-Ta2O5 anode was evaluated from the TOC removal and the UV/Vis absorbance decay. The mineralization was very poor in 0.05 M Na2SO4, whereas it increased considerably at a greater Cl(-) content, meaning that the oxidation mediated by electrogenerated species such as Cl2, HClO, and/or ClO(-) competes and even predominates over the (·)OH-mediated oxidation. The EO treatment of EC-pretreated dairy wastewater allowed obtaining a global 98 % TOC removal, decreasing from 1,062 to <30 mg L(-1).


Assuntos
Alumínio/química , Indústria de Laticínios , Técnicas Eletroquímicas , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias , Cloretos/química , Eletrodos , Eletrólise , Peróxido de Hidrogênio/análise , Indóis , Oxirredução , Sulfatos , Titânio/química , Poluentes Químicos da Água/análise
11.
J Nutr Health Aging ; 18(4): 359-64, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24676315

RESUMO

OBJECTIVES: Health-related quality of life (HRQoL) is a multidimensional health measurement and a key to optimal aging. The aim of this study was to examine the association of nutritional status with HRQoL in the elderly. DESIGN: Cross-sectional study. SETTING: Villanueva Older Health Study, a community-based study in Villanueva de la Cañada (Madrid, Spain). PARTICIPANTS: 83 (53 women) non-institutionalized inhabitants aged 80 years and above. MEASUREMENT: HRQoL was assessed by EuroQoL-5D (EQ-5D) questionnaire, nutritional risk by Mini Nutritional Assessment (MNA) questionnaire and dietary intake by 24-hour dietary recall. Statistical significance was evaluated at 95% confidence level (P<0.05). RESULTS: EQ-5D pointed out differences between men and women (0.782±0.235 and 0.633±0.247; p=0.02). Problems in mobility (total sample) and pain/discomfort (women) dimensions were most frequently reported. MNA (26.5±3.2 men and 24.3±3.2 women; p=0.03) revealed malnutrition in 3.3% of men and 1.9% of women, and risk of malnutrition in 6.7% and 37.7%, respectively. Total sample was at risk of folic acid, zinc, magnesium, vitamin D and vitamin E deficiency. EQ-5D was associated with MNA (p<0.001). EQ-5Dindex was associated with energy intake (p=0.04) and EQ-5Dvas was negatively correlated with body mass index (p=0.02). EQ-5D pain/discomfort dimension was associated with energy (p=0.006), protein (p=0.005), lipid (p=0.03), magnesium (p=0.032), phosphorus (p=0.012), selenium (p=0.043) and niacin (p=0.004) intake. CONCLUSIONS: Women showed poorer HRQoL and higher malnutrition risk. A relationship between HRQoL and risk of malnutrition was observed. Results suggest that when energy and protein, lipid, phosphorus, magnesium, selenium and niacin intake increase, HRQoL is promoted, although the increase does not seem to have a strong direct effect on it. The limited influence of energy and nutrient intake on HRQoL observed requires further research.


Assuntos
Avaliação Geriátrica , Avaliação Nutricional , Estado Nutricional , Qualidade de Vida , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Estudos Transversais , Feminino , Indicadores Básicos de Saúde , Humanos , Masculino , Desnutrição/epidemiologia , Características de Residência , Espanha , Inquéritos e Questionários
12.
An. salud ment ; 11(1/2): 137-142, 1995.
Artigo em Espanhol | LILACS, LIPECS | ID: lil-666471

RESUMO

El Programa de Salud Mental Comunitaria del Instituto Nacional de Salud Mental Honorio Delgado-Hideyo Noguchi desarrollo un programa de rehabilitación dirigido a discapacitados mentales, en los distritos de Independencia y San Martín de Porres. Las actividades del programa comprenden la rehabilitación psicosocial y sociolaboral del enfermo, utilizando en tal proceso los propios recursos de la comunidad. En sus casi 10 años de ejecución se ha logrado la creación de talleres de producción que, además de beneficiar económicamente al paciente, ha permitido su aceptación por parte de la familia y la comunidad.


The Community Mental Health Program of the Instituto Nacional de Salud Mental Honorio Delgado-Hideyo Noguchi carries out a psychosocial rehabilitation program tailored for mental handicapped patients, in Independencia and San Martin de Porres districts. The program involved the psychosocial and socio-occupational rehabilitation of mental patients using community resources. After 10 years of execution the program has founded productive workshops that helping the patient economically have facilitated their acceptance by the family and the community.


Assuntos
Humanos , Pessoas Mentalmente Doentes , Planos e Programas de Saúde , Transtornos Mentais/reabilitação , Peru
13.
Lima; Perú. Ministerio de Salud. Dirección General de Promoción de la Salud; 1; 2008. 22 p. ilus.(Cartillas Informativas, 1).
Monografia em Espanhol | LILACS | ID: lil-650894

RESUMO

La presente publicación prioriza los temas de cuidado a la familia en aulas de clase, de acuerdo a las necesidades sentidas por los docentes del aula.


Assuntos
Educação em Saúde , Medicina de Família e Comunidade , Promoção da Saúde , Peru
14.
Lima; Perú. Ministerio de Salud. Dirección General de Promoción de la Salud; 1; 2008. 22 p. ilus.(Cartillas Informativas, 2).
Monografia em Espanhol | LILACS | ID: lil-650892

RESUMO

La presente publicación prioriza los temas relacionados a salud de la familia en aulas de clase, de acuerdo a las necesidades sentidas por los docentes.


Assuntos
Educação em Saúde , Medicina de Família e Comunidade , Promoção da Saúde , Peru
16.
Lima; INSM. Sub Programa de Salud Mental; 1998. 55 p.
Monografia em Espanhol | LILACS | ID: lil-274156

RESUMO

Contiene: 1. Módulos de intervención psicoafectivos (MIPS); 2. Respuestas emocionales como consecuencia de situaciones de violencia: crisis; 3. Técnica de consejería, apoyo emocional y consejería familiar; 4. Problemas más frecuentes en el niño: ansiedad, depresión, problemas de aprendizaje, maltrato infantil; 5. Problemas más frecuentes en el adolescente; 6. Intervención grupal con niños y adolescentes; 7. Técnicas de relajación; 8. Técnicas participativas; 9. Comunicación popular


Assuntos
Humanos , Masculino , Feminino , Adolescente , Aconselhamento , Saúde Mental , Síndrome da Criança Espancada/psicologia , Violência , Peru
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