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9.
Polymers (Basel) ; 15(17)2023 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-37688148

RESUMEN

The only biotic factor that can satisfy the needs of human species are plants. In order to minimize plastic usage and spread an immediate require of environmental awareness, the globe urges for the development of green composite materials. Natural fibers show good renewability and sustainability and are hence utilized as reinforcements in polymer matrix composites. The present work concerns on the usage of Butea parviflora fiber (BP), a green material, for high end applications. The study throws light upon the characterization of raw and potassium hydroxide (KOH)-treated Butea Parviflora plant, where its physical, structural, morphological, mechanical, and thermal properties are analyzed using the powder XRD, FTIR spectroscopy, FESEM micrographs, tensile testing, Tg-DTA, Thermal conductivity, Chemical composition, and CHNS analysis. The density values of untreated and KOH-treated fibers are 1.238 g/cc and 1.340 g/cc, respectively. The crystallinity index of the treated fiber has significantly increased from 83.63% to 86.03%. The cellulose content of the treated fiber also experienced a substantial increase from 58.50% to 60.72%. Treated fibers exhibited a reduction in both hemicelluloses and wax content. Spectroscopic studies registered varying vibrations of functional groups residing on the fibers. SEM images distinguished specific changes on the raw and treated fiber surfaces. The Availability of elements Carbon, Nitrogen, and Hydrogen were analyzed using the CHNS studies. The tensile strength and modulus of treated fibers has risen to 192.97 MPa and 3.46 Gpa, respectively. Thermal conductivity (K) using Lee's disc showed a decrement in the K values of alkalized BP. The activation energy Ea lies between 55.95 and 73.15 kJ/mol. The fibers can withstand a good temperature of up to 240 °C, presenting that it can be tuned in for making sustainable composites.

10.
Nutr. hosp ; 40(3): 529-533, may.-jun. 2023. tab, graf
Artículo en Español | IBECS | ID: ibc-222013

RESUMEN

Introducción: el haplotipo GA de los polimorfismos rs1554483 y rs4864548 se ha asociado con componentes del síndrome metabólico como la hipertensión arterial y los niveles de triglicéridos. Sus portadores presentan un riesgo de obesidad 1,5 veces mayor que el resto de la población. Metodología: se obtuvieron los SNP rs1554483 y rs4864548 de 2504 individuos desde la base de datos “1000genomes phase 3”. Los datos se agruparon en cinco macropoblaciones (África, Asia Oriental, Asia Meridional, Europa y Latinoamérica) cubriendo un total de 26 poblaciones. Se analizaron las diferencias en la frecuencia del haplotipo entre las macropoblaciones y las poblaciones, para lo cual se utilizó el estadístico F de Fisher. Resultados: la macropoblación de África presentó la menor frecuencia (17,9 %) y la del Este de Asia la mayor (57,4 %). Dentro de las poblaciones existe una relativa homogeneidad en las frecuencias, excepto en el caso de las que componen la macropoblación de Latinoamérica, donde la población peruana de Lima y la puertorriqueña presentan frecuencias mucho mayores que el resto. Conclusiones: el haplotipo GA presenta heterogeneidad entre las macropoblaciones, lo que sugiere procesos microevolutivos altamente diferenciados entre los continentes. Se propone estudiar la asociación del haplotipo GA con otros polimorfismos, como rs3749474, rs11932595 y rs6859524, que también se han asociado con el riesgo de obesidad y factores asociados al síndrome metabólico. (AU)


Introduction: the GA haplotype of polymorphisms rs1554483 and rs4864548 has been associated with components of the metabolic syndrome such as high blood pressure and triglyceride levels; its carriers have a risk of obesity, 1.5 times higher than the rest of the population. Methodology: SNP rs1554483 and rs4864548 were obtained from 2504 individuals from the "1000genomes phase 3" database. Data were grouped into five macro populations (Africa, East Asia, South Asia, Europe and Latin America) covering a total of 26 populations. Differences in haplotype frequency between macro populations and populations were analyzed, for which Fisher's F statistic was used. Results: the macro population of Africa presented the lowest frequency (17.9 %) and that of East Asia the highest (57.4 %). Within the populations there is a relative homogeneity in the frequencies, except in the case of those that make up the macro population of Latin America where the Peruvian population of Lima and the Puerto Rican population present much higher frequencies than the rest. Conclusions: the GA haplotype presents heterogeneity between macro populations, which suggests highly differentiated micro evolutionary processes between continents. We propose to study the association of the GA haplotype with other polymorphisms such as rs3749474, rs11932595 and rs6859524 that have also been associated with risk of obesity and factors associated with metabolic syndrome. (AU)


Asunto(s)
Humanos , Haplotipos , Obesidad/epidemiología , Sobrepeso/epidemiología , Síndrome Metabólico , Prevalencia
11.
Polymers (Basel) ; 15(9)2023 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-37177144

RESUMEN

The present study concerns the physico-chemical, structural, mechanical and thermal characterization of Acacia pennata, a natural and almost inexpensive fibre, as a potential reinforcement in polymer composites. The effect of treating the fibre with sodium acetate to increase its qualities has been seen through the use of thermogravimetric analysis, scanning electron microscope (SEM) analysis, X-ray diffraction (XRD), mechanical property tester, and Fourier transform infrared spectroscopy (FTIR). According to XRD analysis, the elimination of lignin and wax-like impurities resulted in an increase in the AP fibre's crystalline index (79.73%). The fibre's thermal stability was also discovered to be 365 °C. Tensile strength (557.58 MPa) and elongation at break both increased by 2.9% after treatment with sodium acetate. The surface nature and quality of AP fibres improved after sodium acetate treatment. It was confirmed by the reduction of chemical compositions (such as hemicellulose, lignin and pectin). Given its density, the fibre can be suggested as a reinforcement in polymer composites for light-weight applications because its lightweight property will be more useful for composite manufacturing.

12.
Polymers (Basel) ; 15(7)2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-37050416

RESUMEN

Today, new materials based on natural fibres have been emerging day by day to completely eradicate plastics to favour our environmental nature. In this view, the present work is based on the extraction and characterisation of the novel root fibres of the Zea mays (Zm) plant, grown by the hydroponic method. Both the dried untreated and alkali treated root fibres are investigated using a variety of structural, morphological, thermal, elemental and mechanical tests by subjecting both the samples to p-XRD, FT-IR, SEM-EDAX, TGA-DTA, CHNS and tensile strength analyses. Thermal conductivity of the untreated and treated fibres is found using Lee's disc experiment. From p-XRD analysis, the Crystallinity Index, Percentage Crystallinity and Crystallite size of the samples are found. FT-IR studies clarify the different vibrational groups associated with the fibre samples. SEM images show that the surface roughness increases for the chemically treated samples, such that it may be effectively utilised as reinforcement for polymeric composites. The diameter of the fibre samples is found using SEM analysis. According to the EDAX spectrum, Zm fibres in both their raw and processed forms have high levels of Carbon (C) and Oxygen (O). The TGA-DTA tests revealed that the samples of natural fibre have good thermal characteristics. CHNS studies show that Carbon content is high for these samples, which is the characteristic of many natural fibres. Chemical analysis is used to ascertain the prepared samples' chemical makeup. It reveals that both samples have significant amounts of cellulose. The density of the fibres is found to be in the range 0.3-0.6 g/cc, which is much less than any other natural fibre. Therefore, it can be used in light weight applications. From the tensile strength analysis, physical properties such as Young's modulus and micro-fibril angle are determined. The fibres in the roots exhibit a lower tensile strength. Thus, these fibres can be used in powdered form as reinforcement for natural rubber or epoxy composites. After examining all of its properties, it could be reasonably speculated that Zea mays root fibres can be considered as an efficient reinforcement for various matrices to produce attractive bio-composites.

13.
Nutr Hosp ; 40(3): 529-533, 2023 Jun 21.
Artículo en Español | MEDLINE | ID: mdl-36789957

RESUMEN

Introduction: Introduction: the GA haplotype of polymorphisms rs1554483 and rs4864548 has been associated with components of the metabolic syndrome such as high blood pressure and triglyceride levels; its carriers have a risk of obesity, 1.5 times higher than the rest of the population. Methodology: SNP rs1554483 and rs4864548 were obtained from 2504 individuals from the "1000genomes phase 3" database. Data were grouped into five macro populations (Africa, East Asia, South Asia, Europe and Latin America) covering a total of 26 populations. Differences in haplotype frequency between macro populations and populations were analyzed, for which Fisher's F statistic was used. Results: the macro population of Africa presented the lowest frequency (17.9 %) and that of East Asia the highest (57.4 %). Within the populations there is a relative homogeneity in the frequencies, except in the case of those that make up the macro population of Latin America where the Peruvian population of Lima and the Puerto Rican population present much higher frequencies than the rest. Conclusions: the GA haplotype presents heterogeneity between macro populations, which suggests highly differentiated micro evolutionary processes between continents. We propose to study the association of the GA haplotype with other polymorphisms such as rs3749474, rs11932595 and rs6859524 that have also been associated with risk of obesity and factors associated with metabolic syndrome.


Introducción: Introducción: el haplotipo GA de los polimorfismos rs1554483 y rs4864548 se ha asociado con componentes del síndrome metabólico como la hipertensión arterial y los niveles de triglicéridos. Sus portadores presentan un riesgo de obesidad 1,5 veces mayor que el resto de la población. Metodología: se obtuvieron los SNP rs1554483 y rs4864548 de 2504 individuos desde la base de datos "1000genomes phase 3". Los datos se agruparon en cinco macropoblaciones (África, Asia Oriental, Asia Meridional, Europa y Latinoamérica) cubriendo un total de 26 poblaciones. Se analizaron las diferencias en la frecuencia del haplotipo entre las macropoblaciones y las poblaciones, para lo cual se utilizó el estadístico F de Fisher. Resultados: la macropoblación de África presentó la menor frecuencia (17,9 %) y la del Este de Asia la mayor (57,4 %). Dentro de las poblaciones existe una relativa homogeneidad en las frecuencias, excepto en el caso de las que componen la macropoblación de Latinoamérica, donde la población peruana de Lima y la puertorriqueña presentan frecuencias mucho mayores que el resto. Conclusiones: el haplotipo GA presenta heterogeneidad entre las macropoblaciones, lo que sugiere procesos microevolutivos altamente diferenciados entre los continentes. Se propone estudiar la asociación del haplotipo GA con otros polimorfismos, como rs3749474, rs11932595 y rs6859524, que también se han asociado con el riesgo de obesidad y factores asociados al síndrome metabólico.


Asunto(s)
Proteínas CLOCK , Obesidad , Humanos , Haplotipos , Proteínas CLOCK/genética , Polimorfismo de Nucleótido Simple , Obesidad/genética , Síndrome Metabólico/genética , Grupos Raciales/genética , Genética de Población
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