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1.
Int J Biol Macromol ; 260(Pt 2): 129579, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38266852

RESUMO

High Energy Ball-Milling (HEBM) modifies starchs' granule morphology, physicochemical properties, and chemical structure. However, understanding how the HEBM changes the starch chemical structure is necessary to control these modifications. Therefore, this study aimed to investigate the changes in potato starch's long- and short-range molecular order during HEBM at different environmental conditions such as oxygen (Air) and humidity content. Due to the correlation between the starch modification and the energy supplied (Esupp) by the HEBM, Burgio's equation was used to calculate this energy. The starch transformation was followed by X-ray diffraction, Fourier Transform-Infrared Spectroscopy, and Raman spectroscopy. A Principal Component Analysis (PCA) was conducted to reduce the HEBM variables. PAC analysis demonstrated that the different oxygen-humidity conditions do not affect the HEBM of potato starch. Based on the starch chemical structure transformation correlated with Esupp during HEBM, four stages were observed: orientation, modification, mechanolysis, and over-destruction. It was identified for the first time that at low milling energy (<1.5 kJ/g, orientation stage), the glycosidic rings change their orientation, and starch-water interaction increases while the starch's organization reduces. Ergo, the potato starch could be more susceptible to chemical modifications during the first two stages.


Assuntos
Solanum tuberosum , Solanum tuberosum/química , Amilose/química , Umidade , Oxigênio , Amido/química , Difração de Raios X
2.
Sci Rep ; 12(1): 14641, 2022 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-36030345

RESUMO

Dietary changes are the major variation cause in the composition of the gut microbiota. The short lactation phase in phocids provides an exceptional opportunity to explore the microbiota's response to a quick transition from a milk-based to a solid diet. We investigated the effects of age and sex on the gut microbiota of harbor seals in Mexico using rectal and fecal samples from pups and adults. 16S gene sequencing revealed age explains most of the observed variations in microbial composition. Individuals with frequent contact (pups-female adults) have major microbial similarities than those with little or no contact (pups-male adults). Overall, adults and females (regardless of sex and age, respectively) have a greater microbial richness; as seals grow, the core microbiome shrinks, and microbial diversity increases. We found pathways related to milk and chitin digestion in pups' microbiomes, indicating pups were transitioning to a solid diet. An enrichment of routes related to dramatic weight loss and body mass indicated higher metabolic stress in pups in late breeding season, when they are weaned and start intermittent fasting. Our findings highlight the host-microbiome interaction in harbor seals during late breeding season in response to food shifts and metabolic stress.


Assuntos
Microbioma Gastrointestinal , Phoca , Animais , Dieta , Fezes , Feminino , Masculino , Leite , RNA Ribossômico 16S
3.
Food Res Int ; 140: 109870, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33648188

RESUMO

Pure potato starch has been modified by high-energy-ball-milling as a function of energy supplied, aiming to obtain products for different possibilities of industrial application. Burgios's equation has been used to calculate the energy supplied. The effect of the milling has been followed by a characterization of the starch morphology, crystallinity, solubility, swelling, retrogradation, viscosity, apparent viscosity, functional groups, and reducing sugar concentration. The high-energy-ball-milling not only changes the physical properties but also induces the mechanolysis of potato starch, breaking the glycosidic linkages of the starch molecules. A representation of the possible mechanism of starch mechanolysis is proposed. Three stages of the transformation of potato starch through high-energy ball-milling can be identified. Each of these stages generates starch with properties that can be used in different industrial applications.


Assuntos
Solanum tuberosum , Solubilidade , Amido , Viscosidade
4.
Waste Manag ; 114: 183-195, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32679476

RESUMO

Generation and inadequate management of solid waste constitute a global challenge. Projections for 2050 portend an annual increase of 3.40 billion tons of waste. This study assessed the impact of an environmental education intervention (EEI) aimed at reducing waste generation and fomenting pro-environmental behaviors in an academic public-health institution in Mexico. The EEI was implemented over 20 months using a model of behavior change. Using a mixed-method design (QUAN + qual), baseline and follow-up measurements were performed through electronic questionnaires (n = 754), focus groups (n = 20), and waste quantification. A double-difference model was performed to measure pro-environmental behaviors impact: overall and by sex, age, educational level and function within the institution. Waste quantification was performed using a quartering method and weekly monitoring. The qualitative data were studied through thematic analysis. As a result of the EEI, women reduced their use of multilayer packaging (-15.6 pp, p < 0.05) and frequent use of non-ecological materials (-17.6 pp, p < 0.05). Graduate-level participants reduced their regular and frequent use of these materials (-33.3 pp, p < 0.05, 27.6 pp, p < 0.01), while those with lower educational levels increased their ecological behavior at home (12.1 pp, p < 0.05). Waste generation dropped by 60.1% vis-a-vis the baseline measurement. Our qualitative findings showed a relationship between holding a position of power in the institution and recycling. They also revealed that available infrastructure for separating waste contributed substantially to the observed impact. With actions centered on physical structure, community practice and institutional policy components, the EEI improved the pro-environmental behaviors and perceptions of participants.


Assuntos
Reciclagem , Gerenciamento de Resíduos , Feminino , Humanos , México , Embalagem de Produtos , Resíduos Sólidos , Inquéritos e Questionários
5.
Med Teach ; 42(9): 1051-1057, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32697116

RESUMO

BACKGROUND: Medical curricula have historically been designed in a top-down approach, usually excluding students. While Delphi panels have been used as a tool for medical education curricula design, none have been conducted in Ecuador. In addition, no such approach has ever included students both as panelists and researchers. MATERIAL AND METHODS: Four Delphi panels were developed and conducted using a participatory approach that allowed medical students to take part both as expert panelists and researchers: specifically, students developed the questionnaire and conducted a qualitative synthesis. Questionnaire responses were anonymized and dispatched online to panelists. The information was organized and collected to develop the qualitative syntheses and prepare the final statements. RESULTS: Thirty-two medical students participated between February and May 2018. A total of 32 questions were developed, corresponding to five different categories. For some questions, consensus was reached; for other questions, general statements were obtained.Discussion and conclusion: Developing the questionnaire, responding to it and analyzing the answers allowed students to raise significant concerns regarding medical education topics proposing relevant policy and curricula change. Participatory Delphi panels can be an efficient tool to obtain organized feedback, improve student class involvement, and promote research skills.


Assuntos
Educação de Graduação em Medicina , Educação Médica , Estudantes de Medicina , Currículo , Técnica Delphi , Equador , Humanos
6.
Genet Mol Res ; 15(4)2016 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-28002590

RESUMO

Several interleukin 6 gene (IL6) polymorphisms are implicated in susceptibility to rheumatoid arthritis (RA). It has not yet been established with certainty if these polymorphisms are associated with the severe radiographic damage observed in some RA patients, particularly those with the development of joint bone ankylosis (JBA). The objective of the present study was to evaluate the association between severe radiographic damage in hands and the -174G/C and -572G/C IL6 polymorphisms in Mexican Mestizo people with RA. Mestizo adults with RA and long disease duration (>5 years) were classified into two groups according to the radiographic damage in their hands: a) severe radiographic damage (JBA and/or joint bone subluxations) and b) mild or moderate radiographic damage. We compared the differences in genotype and allele frequencies of -174G/C and -572G/C IL6 polymorphisms (genotyped using polymerase chain reaction-restriction fragment length polymorphism) between these two groups. Our findings indicated that the -174G/C polymorphism of IL6 is associated with severe joint radiographic damage [maximum likelihood odds ratios (MLE_OR): 8.03; 95%CI 1.22-187.06; P = 0.03], whereas the -572G/C polymorphism of IL6 exhibited no such association (MLE_OR: 1.5; 95%CI 0.52-4.5; P = 0.44). Higher anti-cyclic citrullinated peptide antibody levels were associated with more severe joint radiographic damage (P = 0.04). We conclude that there is a relevant association between the -174G/C IL6 polymorphism and severe radiographic damage. Future studies in other populations are required to confirm our findings.


Assuntos
Artrite Reumatoide/genética , Traumatismos da Mão/genética , Mãos/efeitos da radiação , Interleucina-6/genética , Polimorfismo de Nucleotídeo Único , Adulto , Artrite Reumatoide/complicações , Artrite Reumatoide/etnologia , Feminino , Predisposição Genética para Doença , Traumatismos da Mão/etnologia , Traumatismos da Mão/etiologia , Humanos , Masculino , México/etnologia , Pessoa de Meia-Idade
8.
Acta Crystallogr B ; 61(Pt 1): 11-6, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15659852

RESUMO

Single microcrystals of the new compound samarium dimanganese germanium oxide, SmMn2GeO7, were grown using the flux method in a double spherical mirror furnace (DSMF). The micrometric crystals were observed and chemically analysed with scanning electron microscopy (SEM) and X-ray energy dispersive spectroscopy (EDX). The structural characterization and chemical analysis of these crystals were also carried out using transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM), together with electron-energy-loss spectroscopy (EELS). We found that the new quaternary compound crystallizes in the orthorhombic system with the point group mmm (D2h), space group Immm (No. 71) and cell parameters a=8.30 (10), b=8.18 (10), c=8.22 (10) A and V=558.76 A3.


Assuntos
Germânio/química , Manganês/química , Microscopia Eletrônica/métodos , Oxigênio/química , Samário/química , Cristalografia/métodos , Modelos Moleculares , Estrutura Molecular
9.
Rev Biol Trop ; 48(4): 927-30, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11487937

RESUMO

This paper presents a new method for the recovery of marked seagrass blades. The introduction of a plastic belt surrounding the marked shoot at a sediment level provided a relocation arrangement which was unloosed by drag forces or grazing. The relocation method was tested on Zostera marina L. It proved to have the advantage of increasing dramatically the number of marked shoots recovered up to 100% while reducing the cost of the procedure to a minimum. An allometric model indicated that the introduced relocation method has no impact on the development of the plant.


Assuntos
Botânica/instrumentação , Folhas de Planta/crescimento & desenvolvimento , Poaceae/crescimento & desenvolvimento , Água do Mar
11.
Rev Dent Chile ; 81(2): 65-73, 1990.
Artigo em Espanhol | MEDLINE | ID: mdl-2244072

RESUMO

Intracapsular dysfunction of the TMJ is analyzed, based on the concepts of dysfunctional and functional pathology, including a diagnostic clasification this is analyzed under a etiopathogenic point of view, clinical characteristics, different types of cases named disco-condilar disorders.


Assuntos
Transtornos da Articulação Temporomandibular/classificação , Cartilagem Articular/fisiopatologia , Oclusão Dentária Traumática/fisiopatologia , Humanos , Luxações Articulares/fisiopatologia , Côndilo Mandibular/fisiopatologia , Transtornos da Articulação Temporomandibular/fisiopatologia
12.
Rev Dent Chile ; 80(2): 89-95, 1989 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-2640342

RESUMO

We described therapeutical aspects for treatment of moderated temporomandibular subluxation of the joint disc, with emphasis about the concepts of reduction and immobilization of traumatology, previous to the functional rehabilitation. We used a technique in 14 patients that were previously diagnosed clinical and radiographically, and within the diagnostic procedures we estimated temporomandibular disturbances as an important factor in pre and post treatment to obtain articular stabilization.


Assuntos
Contenções , Transtornos da Articulação Temporomandibular/terapia , Cartilagem Articular/patologia , Oclusão Dentária , Humanos , Imobilização , Luxações Articulares/terapia , Radiografia , Transtornos da Articulação Temporomandibular/diagnóstico por imagem , Transtornos da Articulação Temporomandibular/reabilitação
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