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1.
Macromol Rapid Commun ; 38(6)2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28117502

RESUMEN

Fractal colloids, which find applications in the preparation of advanced materials, are currently synthesized by means of a multistep procedure that yields a low solids content dispersion. This is not well suited for certain applications such as superhydrophobic coatings. In this work, a one-step method for the synthesis of higher solids content waterborne fractal polymer dispersions is presented and it is shown that the surfaces obtained from the fractal dispersions are superhydrophobic (contact angle, θ > 150°) which is beyond the current waterborne coating technology (θ = 130°-137°). This opens the possibility for the large-scale production of waterborne superhydrophobic coatings.


Asunto(s)
Fractales , Polimerizacion , Polímeros/síntesis química , Interacciones Hidrofóbicas e Hidrofílicas , Tamaño de la Partícula , Polímeros/química , Propiedades de Superficie
2.
Langmuir ; 32(30): 7459-66, 2016 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-27400332

RESUMEN

This work reports on the formation of highly hydrophobic coatings from waterborne latexes able to form films at ambient temperature. The contact angle of film forming copolymers of 2-ethylhexyl acrylate and perfluorodecyl acrylate (PFDA) was limited to 114° because flat surfaces were obtained. Attempts to increase the roughness of the film using blends of film-forming latexes with the latex of PFDA homopolymer (which is not film forming) were not successful under regular casting conditions because the PFDA particles accumulated at the film-substrate interface. Film formation engineering allowed modifying the morphology of the film obtaining a contact angle of 137°.

3.
Soft Matter ; 12(33): 7005-11, 2016 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-27476531

RESUMEN

Coatings have a tremendous impact on economy as they reduce corrosion that has an estimated cost of 3% of the world's GDP. Hydrophobic coatings are particularly efficient for this purpose and the challenge is to produce cost effective and environmentally friendly, highly hydrophobic, cohesive and non-porous coatings applicable to large and irregular surfaces. This work shows that this goal can be achieved by forming wrinkles on the surface of waterborne coatings through fine-tuning of the film forming conditions. The proof of concept was demonstrated by using waterborne dispersions of copolymers of 1H,1H,2H,2H-perfluorodecyl acrylate and 2-ethylhexyl acrylate, and using the temperature and hardness of the copolymer as control variables during film formation. This allowed the formation of transparent films with a wrinkled surface that had a contact angle of 133°, which represents an increase of 20° with respect to the film cast under standard conditions.

4.
Materials (Basel) ; 16(16)2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37629914

RESUMEN

The effect of the addition of Fe0 and Fe3+ on the formation of expanded clay aggregates was studied using iron-free kaolin as an aluminosilicates source. Likewise, the incorporation of cork powder as a source of organic carbon and Na2CO3 as a flux in the mixtures was investigated in order to assess its effect in combination with the iron phases. An experimental protocol, statistically supported by a mixture experiments/design of experiments approach, was applied to model and optimize the bloating index, density, absorption capacity, and mechanical strength. The process of expansion and pore generation and the associated decrease in density required the addition of iron, such that the optimum mixtures of these properties presented between 25 and 40 wt.% of Fe0 or Fe3+, as well as the incorporation of 3.5-5 wt.% of organic carbon. The addition of Fe3+ produced a greater volumetric expansion (max. 53%) than Fe0 (max. 8%), suggesting that the formation of the FeO leading to this phenomenon would require reducing and oxidizing conditions in the former and the latter, respectively. The experimental and model-estimated results are in good agreement, especially in the aggregates containing Fe0. This reinforces the application of statistical methods for future investigations.

5.
Food Chem ; 331: 127192, 2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-32569963

RESUMEN

Melatonin and serotonin are bioactive compounds present in foods and beverages and related to neuroprotection and anti-angiogenesis, among other activities. They have been described in wines and the role of yeast in their formation is clear. Thus, this study evaluates the content of these bioactives and other related indolic compounds in beer. For this purpose, commercial beers were analyzed by a validated UHPLC-HRMS method and sample treatment optimized due to the low concentrations expected. Moreover, a wort was fermented with different commercial beer yeast (Abbaye, Diamond, SafAle, SafLager) in order to monitor the formation of these bioactives during the elaboration process. Results show that indolic compounds such as N-acetylserotonin and 3-indoleacetic acid are produced during the alcoholic fermentation of wort. Moreover, the occurrence of four indolic compounds (5-hydroxytryptophan, N-acetylserotonin, 3-indoleacetic acid, l-tryptophan ethyl ester) in commercial beers is reported for the first time.


Asunto(s)
Cerveza/análisis , Cerveza/microbiología , Indoles/metabolismo , Melatonina/metabolismo , Triptófano/metabolismo , Bebidas , Cromatografía Líquida de Alta Presión/métodos , Fermentación , Análisis de los Alimentos/métodos , Almacenamiento de Alimentos , Indoles/análisis , Melatonina/análisis , Saccharomyces cerevisiae/metabolismo , Serotonina/análogos & derivados , Temperatura , Triptófano/análogos & derivados
6.
Women Birth ; 32(1): e43-e48, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29754970

RESUMEN

BACKGROUND: Some studies have suggested an association between synthetic oxytocin administration and type of birth with the initiation and consolidation of breastfeeding. AIM: This study aimed to test whether oxytocin administration and type of birth are associated with cessation of exclusive breastfeeding at different periods. A second objective was to investigate whether the administered oxytocin dose is associated with cessation of exclusive breastfeeding. METHODS: We conducted a prospective cohort study (n=529) in a tertiary hospital. Only full-term singleton pregnancies were included. Four groups were established based on the type of birth (vaginal or cesarean) and the intrapartum administration of oxytocin. Follow-up was performed to evaluate the consolidation of exclusive breastfeeding at 1, 3 and 6months. FINDINGS: During follow-up, the proportion of exclusive breastfeeding decreased in all groups. After adjusting for confounding variables, the group with cesarean birth without oxytocin (planned cesarean birth) had the highest risk of cessation of exclusive breastfeeding (odds ratio [95% confidence interval], 2.51 [1.53-4.12]). No association was found between the oxytocin dose administered during birth and puerperium period and the cessation of exclusive breastfeeding. CONCLUSION: Planned cesarean birth without oxytocin is associated with the cessation of exclusive breastfeeding at 1, 3 and 6months of life. It would be desirable to limit elective cesarean births to essentials as well as to give maximum support to encourage breastfeeding in this group of women. The dose of oxytocin given during birth and puerperium period is not associated with cessation of exclusive breastfeeding.


Asunto(s)
Lactancia Materna , Parto Obstétrico , Oxitocina/administración & dosificación , Adulto , Alimentación con Biberón , Cesárea , Femenino , Humanos , Recién Nacido , Embarazo , Estudios Prospectivos
7.
Breastfeed Med ; 12(7): 430-435, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28787188

RESUMEN

AIM: To analyze the association of labor and sociodemographic factors with cessation of exclusive breastfeeding (EBF) at 3 and 6 months of life. MATERIALS AND METHODS: A prospective cohort study (n = 529) was performed in a tertiary hospital with the Baby-Friendly Hospital Initiative (BFHI) award. Labor and sociodemographic factors were investigated. Single-term newborns were included. After 3 and 6 months, telephone calls were made to determine the type of lactation. Univariate analysis was performed with the chi-square test or Fisher's exact test. Multivariable logistic regression models were developed to determine risk factors associated with cessation of breastfeeding at 3 and 6 months. RESULTS: At 3 months, 523 participants (98.9%) were contacted, of whom 64.4% maintained EBF. Factors associated with cessation were pacifier use (odds ratio [OR] 3.49; 95% confidence interval [95% CI] 2.24-5.43), cesarean delivery (OR 4.49; 95% CI 2.96-6.83), no college degree (OR 2.01; 95% CI 1.35-3.01), and not attending breastfeeding support groups (OR 1.96; 95% CI 1.22-3.12). At 6 months, 512 participants (96.8%) were contacted, of whom 31.4% maintained EBF. Factors associated with cessation were reintegration into the workplace (OR 4.49; 95% CI 2.96-6.83), pacifier use (OR 3.49; 95% CI 2.24-5.43), and primiparity (OR 1.61; 95% CI 1.05-2.46). CONCLUSIONS: Several risk factors are associated with the premature cessation of EBF. There is a need to define strategies to correct modifiable factors and to promote protective factors with the aim of improving the success rate of EBF to reach the recommendations of the World Health Organization.


Asunto(s)
Lactancia Materna/estadística & datos numéricos , Adulto , Lactancia Materna/psicología , Escolaridad , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Chupetes/estadística & datos numéricos , Paridad , Estudios Prospectivos , Reinserción al Trabajo/estadística & datos numéricos , Factores de Riesgo , Apoyo Social , Factores Socioeconómicos , España , Factores de Tiempo
8.
Oncol Nurs Forum ; 43(3): E104-20, 2016 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-27105202

RESUMEN

PROBLEM IDENTIFICATION: To determine (a) the average levels of emotional exhaustion (EE), depersonalization (D), and personal accomplishment (PA) among oncology nurses; (b) the prevalence of low, medium, and high levels of burnout for each dimension; and (c) the risk factors for burnout.
. LITERATURE SEARCH: A systematic review was carried out using the CUIDEN, CINAHL®, LILACS, ProQuest, PubMed, SciELO, and Scopus databases. 
. DATA EVALUATION: The 436 search results obtained were reduced to a final sample of 27 articles after applying the inclusion and exclusion criteria.
. SYNTHESIS: With respect to levels of burnout, published results differ in their conclusions. In general, they indicate that oncology nurses feel little sense of PA and suffer from EE, although few signs of D exist. 
. CONCLUSIONS: Oncology nurses present high levels of EE and of reduced PA. A large proportion of these nurses are at risk of developing burnout. Age, work experience, workload, and communication skills are among the factors that may influence development of the syndrome. 
. IMPLICATIONS FOR PRACTICE: Programs should be developed to identify interventions that would reduce EE and enhance feelings of PA. In addition, risk factors and protective measures should be studied more comprehensively.


Asunto(s)
Agotamiento Profesional/psicología , Satisfacción en el Trabajo , Personal de Enfermería en Hospital/psicología , Enfermería Oncológica , Adulto , Agotamiento Profesional/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , España/epidemiología , Estrés Psicológico/epidemiología , Encuestas y Cuestionarios
9.
Actual. SIDA. infectol ; 28(104): 134-140, 2020 dic. tab
Artículo en Español | LILACS, BINACIS | ID: biblio-1349063

RESUMEN

Con el avance de la pandemia por COVID-19, la aparición de pacientes con un segundo episodio confirmado por reacción en cadena de la polimerasa, con transcripción inversa (rt-PCR) compatible con reinfección, puso de manifiesto la falta de recomendaciones para su abordaje.Presentamos un estudio descriptivo multicéntrico retro-prospectivo de una serie de doce casos atendidos entre el 01/06/2020 y el 20/10/2020. En la misma, diez casos presentaron el segundo episodio en un período de tiempo menor a 90 días.Por su complejidad, la confirmación de una reinfección no está al alcance en la práctica diaria. Esto requiere de estudios que incluyan comparaciones genómicas de cepas virales involucradas en ambos episodios, determinación de la infectividad del ARN por cultivo viral y análisis molecular.Es necesario establecer definiciones operativas y algoritmos clínicos para la atención de los segundos episodios


As COVID-19 pandemic progresses, patients with a second confirmed episode by reverse transcription-polymerase chain reaction (RT PCR) compatible with reinfection reveals the lack of recommendations for its approach.A multicenter retro-prospective descriptive work was done of a series of 12 cases evaluated between June 1, 2020 and October 20, 2020. In this study, 10 out of 12 cases presented the second episode occurred in less than 90 days.Due to the diagnosing reinfection complexity, its confirmation is not available in the daily practice, this requires studies, which include viral strains genomic comparisons involved in both episodes, ARN determination infectivity by viral culture and molecular analysis.It is necessary to establish operational and clinical algorithms definitions to assist second episodes


Asunto(s)
Humanos , Adulto , Persona de Mediana Edad , Anciano , Epidemiología Descriptiva , Estudios Retrospectivos , Estudio Multicéntrico , Esparcimiento de Virus , Toma de Decisiones , Atención Ambulatoria , Reinfección/terapia , ARN Polimerasa Dependiente de ARN de Coronavirus/inmunología , Hospitalización
12.
Rev. clín. med. fam ; 10(1): 18-28, feb. 2017. tab, graf
Artículo en Español | IBECS (España) | ID: ibc-162530

RESUMEN

Objetivo: Evaluar la calidad de la prescripción de los nuevos anticoagulantes orales. Identificar posibles factores asociados a su utilización inadecuada. Diseño: Estudio descriptivo transversal. Emplazamiento: Zona Básica de Salud urbana. Participantes: Todos los pacientes que consumieron nuevos anticoagulantes orales (NACO) durante 2015 (153 sujetos). Mediciones Principales: Adecuación de la prescripción a las recomendaciones de la Agencia Española de Medicamentos y Productos Sanitarios (AEMPS). Otras variables: NACO prescrito (clasificación ATC), indicación y duración del tratamiento, prescriptor, Índice de Charlson, polimedicación (5 o más fármacos), uso de servicios sanitarios y variables sociodemográficas. Análisis multivariante para determinar posibles factores asociados al uso inadecuado. Resultados: 145 sujetos incluidos (23,8 % del total de usuarios de anticoagulantes orales). Edad media 76 años (DE:11,4), un 50,3 % mujeres. Rivaroxaban el más prescrito (41,4 %). Indicación y prescriptor principal: fibrilación auricular no valvular -FANV- (93,1 % de casos) y cardiólogos (71,7 %). Mediana de uso de 20 meses (rango intercuartil: 8 a 32). Utilizaban acenocumarol el 46,9 % de pacientes y el motivo habitual de cambio: mal control del INR. En el 74,1 % (100 casos) (IC 95 %: 65,8 - 81,2) el uso global de NACO (pacientes con FANV) fue inadecuado. Variables asociadas al uso inadecuado: no prescribir de inicio el NACO (OR: 7,0; IC 95 %: 1,8 - 27,1) y la mayor duración del tratamiento anticoagulante (OR: 2,4; IC 95 %: 1,3 - 4,5). Conclusiones: En nuestro entorno una de cada cuatro prescripciones de los nuevos anticoagulantes, en pacientes con FANV, sigue las recomendaciones de la AEMPS. Debemos estar alerta ante posibles riesgos de este elevado uso inadecuado (AU)


Objective: To assess the quality of prescription of the new oral anticoagulants. To identify possible factors associated with its inappropriate use. Design: Descriptive cross-sectional study. Location: Urban primary healthcare district. Participants: All patients who used new oral anticoagulants (NOAC) during 2015 (153 subjects). Main measurements: Prescription compliance to the recommendations of the Spanish Agency of Medicines and Medical Devices (AEMPS). Other variables: NOAC prescribed (ATC classification), indication and duration of treatment, prescriber, Charlson index, polypharmacy (5 or more drugs), use of healthcare services, and socio-demographic variables. Multivariate analysis to determine possible factors associated with inappropriate use. Results: 145 subjects were included (23.8 % of the total users of oral anticoagulants). Average age 76 years (SD:11.4), 50.3 % were women. Rivaroxaban the most prescribed (41.4 %). Indication and usual prescriber: non-valvular atrial fibrillation - NVAF - (93.1 % of cases) and cardiologists (71.7 %). The median of use was 20 months (interquartile range: 8 to 32). 46.9 % of patients used acenocoumarol, and the usual reason for the change was poor INR control. In 74.1 %(100 cases) (CI 95 %: 65.8 - 81.2) the global use of NOAC, in patients with NVAF, was inappropriate. Variables associated with inappropriate use: not to prescribe NOAC from the beginning (OR: 7.0; CI 95 %: 1.8 - 27.1) and longer duration of anticoagulant therapy (OR: 2.4; CI 95 %: 1.3 - 4.5).Conclusion: . In our environment, one of every four prescriptions of new anticoagulants, in patients with NVAF, follows the recommendations of the AEMPS. We must be vigilant against possible risks of this high inappropriate use (AU)


Asunto(s)
Humanos , Masculino , Femenino , Anciano , Medicamentos bajo Prescripción/uso terapéutico , Anticoagulantes/uso terapéutico , Atención Primaria de Salud/métodos , Calidad de la Atención de Salud/normas , Estudios Transversales/métodos , Población Urbana/estadística & datos numéricos , Prescripción Inadecuada/efectos adversos , Prescripción Inadecuada/prevención & control , Encuestas y Cuestionarios
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