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1.
Chem Rev ; 124(4): 1649-1737, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38320111

RESUMO

Ionic liquids (ILs) are promising alternative compounds that enable the development of technologies based on their unique properties as solvents or catalysts. These technologies require integrated product and process designs to select ILs with optimal process performances at an industrial scale to promote cost-effective and sustainable technologies. The digital era and multiscale research methodologies have changed the paradigm from experiment-oriented to hybrid experimental-computational developments guided by process engineering. This Review summarizes the relevant contributions (>300 research papers) of process simulations to advance IL-based technology developments by guiding experimental research efforts and enhancing industrial transferability. Robust simulation methodologies, mostly based on predictive COSMO-SAC/RS and UNIFAC models in Aspen Plus software, were applied to analyze key IL applications: physical and chemical CO2 capture, CO2 conversion, gas separation, liquid-liquid extraction, extractive distillation, refrigeration cycles, and biorefinery. The contributions concern the IL selection criteria, operational unit design, equipment sizing, technoeconomic and environmental analyses, and process optimization to promote the competitiveness of the proposed IL-based technologies. Process simulation revealed that multiscale research strategies enable advancement in the technological development of IL applications by focusing research efforts to overcome the limitations and exploit the excellent properties of ILs.

2.
Physiol Rev ; 98(3): 1371-1415, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29767564

RESUMO

Excessive energy intake and reduced energy expenditure drive the development of insulin resistance and metabolic diseases such as obesity and type 2 diabetes mellitus. Metabolic signals derived from dietary intake or secreted from adipose tissue, gut, and liver contribute to energy homeostasis. Recent metabolomic studies identified novel metabolites and enlarged our knowledge on classic metabolites. This review summarizes the evidence of their roles as mediators of interorgan crosstalk and regulators of insulin sensitivity and energy metabolism. Circulating lipids such as free fatty acids, acetate, and palmitoleate from adipose tissue and short-chain fatty acids from the gut effectively act on liver and skeletal muscle. Intracellular lipids such as diacylglycerols and sphingolipids can serve as lipotoxins by directly inhibiting insulin action in muscle and liver. In contrast, fatty acid esters of hydroxy fatty acids have been recently shown to exert a series of beneficial effects. Also, ketoacids are gaining interest as potent modulators of insulin action and mitochondrial function. Finally, branched-chain amino acids not only predict metabolic diseases, but also inhibit insulin signaling. Here, we focus on the metabolic crosstalk in humans, which regulates insulin sensitivity and energy homeostasis in the main insulin-sensitive tissues, skeletal muscle, liver, and adipose tissue.


Assuntos
Metabolismo Energético , Resistência à Insulina , Receptor Cross-Talk , Homeostase , Humanos
3.
J Sci Food Agric ; 103(6): 2773-2785, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36598243

RESUMO

BACKGROUND: Nixtamalized flour snacks such as tortilla chips are widely consumed across the world, but they are nutritionally poor and contribute to obesity and other non-communicable diseases. The production of healthy versions of such snacks, by incorporating vegetables and improving the quality of the flours used in their formulation, could help address these nutritional challenges. This study compared the fortification of baked tortilla chips with vegetable leaf powders (kale and wild amaranth at 0%, 4%, 8%, and 16% w/w) and using two types of nixtamalized flour: traditional (TNF) and with ohmic heating (OHF). RESULTS: Overall, the use of OHF increased 1.88 times the fibre in enriched and non-enriched snacks with respect to TNF, but the latter had 1.85 times more protein. Addition of 16% of vegetable powders increased protein (kale = 1.4-fold; amaranth = 1.3-fold) and dietary fibre (kale = 1.52-fold; amaranth = 1.7-fold). Amaranth enrichment improved total phenolic content (TPC) and total flavonoid content (TFC) of chips at least 1.2 and 1.63 times, respectively. OHF chips also had higher bound TPC than TNF ones, regardless of vegetable addition. Combinations of OHF with 16% amaranth produced chips 1.74-fold higher in antioxidant capacity than non-enriched ones, due to increased content of phenolics such as ferulic acid. CONCLUSION: This work showed that tortilla chips made using nixtamalized flour produced with assisted ohmic heating, alone or in combination with wild amaranth leaf powder, could be used in the production of healthy maize snacks to enhance their prospective antioxidant activity and nutritional value. © 2023 Society of Chemical Industry.


Assuntos
Amaranthus , Brassicaceae , Verduras/metabolismo , Farinha/análise , Manipulação de Alimentos/métodos , Lanches , Calefação , Estudos Prospectivos , Suplementos Nutricionais , Antioxidantes/análise , Fenóis/análise , Brassicaceae/metabolismo , Amaranthus/química
4.
Doc Ophthalmol ; 143(1): 99-106, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33956290

RESUMO

INTRODUCTION: Neuronal ceroid lipofuscinoses (CLN) are neurodegenerative disorders among the most frequent, inherited as an autosomal recessive trait. Affected patients can present with progressive decline in cognitive and motor functions, seizures, a shortened life span and visual deficiency. CLN2 is one of the rare CLN that benefits from treatment by cerliponase alpha an enzyme replacement therapy. Preliminary results on treated animal models have shown delayed neurological signs and prolonged life span. However, cerliponase alpha did not prevent vision loss or retinal degeneration in those animal models. Cerliponase alpha has currently been delivered to a few CLN2-affected patients. We report the case of one patient suffering from CLN2 treated with intracerebroventricular infusions of cerliponase alpha 300 mg every two weeks. Evolution of his retinal function was assessed by three successive flash-ERG and flash-VEP recordings throughout his treatment over a 4-year period. RESULTS: Before treatment at the age of 4 years 5 months, patient's retinas were normal (normal fundi and normal flash-ERG). After 29 infusions at the age of 6 years 10 months, a-wave combined response was absent, while cone and flicker responses were normal. After 80 infusions at the age of 8 years 9 months, a-wave cone response was absent with b-wave peak time increased, and no combined response. COMMENTS: Despite treatment, our patient's retinas showed a progressive abnormal and inhomogeneous function. Rods function was altered first, then the scotopic system and afterward, the cones. This result differs from those recorded in animal models. The relative preservation of cone functioning for a while could not be unequivocally attributed to enzyme replacement therapy as we lack comparison with the evolution of flash-ERGs recorded in untreated subjects.


Assuntos
Lipofuscinoses Ceroides Neuronais , Degeneração Retiniana , Animais , Criança , Pré-Escolar , Eletrorretinografia , Terapia de Reposição de Enzimas , Humanos , Lipofuscinoses Ceroides Neuronais/tratamento farmacológico , Retina/diagnóstico por imagem , Regulador Transcricional ERG , Tripeptidil-Peptidase 1
5.
Dev Med Child Neurol ; 62(4): 528-530, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31489614

RESUMO

Neuronal ceroid lipofuscinoses (NCLs) are rare, progressive disorders. Through this series of 20 patients with NCL, we illustrate differences between subtypes in their presenting symptoms and clinical, imaging, and electrophysiological results to raise awareness of symptom diversity. Data were available on presenting symptoms, genetics, magnetic resonance imaging (MRI), electroencephalography (including with low-frequency intermittent photic stimulation), visual responses, and electron microscopy. Causal mutations were identified in 10 patients. Eleven patients had neuronal ceroid lipofuscinosis type 2 (CLN2) disease and their most common presenting symptom was seizures, although motor and language defects were also reported. Five patients with CLN2 disease showed abnormalities at initial MRI, but only three showed a photic response with low-frequency stimulation. Seizures were not as common a presenting symptom in other NCL subtypes. Patients with NCLs present with diverse symptoms, which may not be characteristic in early disease stages. These signs and symptoms should lead to rapid diagnostic confirmatory testing for NCLs. WHAT THIS PAPER ADDS: Disease presentation is not uniform for neuronal ceroid lipofuscinoses. Characteristic clinical test results may not be identified in early disease stages.


Assuntos
Encéfalo/diagnóstico por imagem , Lipofuscinoses Ceroides Neuronais/diagnóstico , Encéfalo/fisiopatologia , Pré-Escolar , Eletroencefalografia , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Lipofuscinoses Ceroides Neuronais/diagnóstico por imagem , Lipofuscinoses Ceroides Neuronais/fisiopatologia , Estudos Retrospectivos , Tripeptidil-Peptidase 1
6.
Molecules ; 25(9)2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32397673

RESUMO

In our attempts to prepare coordination polymers by reaction of FeCl3·6H2O and Ni(OH)2 in the presence of dithiolenes HSC6H2X2SH (X = Cl or H), several ion pairs of compounds containing the anionic entity [Ni(SC6H2X2S)2]- were obtained instead. It was also found that other species without dithiolene ligands were formed in these reactions, giving rise to different ion pairs and a tetrametallic cluster. The careful isolation of the different types of crystalline solids allowed the characterization of all of the resulting compounds by single crystal X-ray diffraction (SCXRD). In order to establish the amount of nickel and iron present in the crystals, complementary total reflection X-ray fluorescence (TXRF) analyses were performed. The eight different structural types that were obtained are described and compared with related ones found in the literature.


Assuntos
Compostos de Ferro/química , Ferro/química , Níquel/química , Ligantes , Modelos Moleculares , Estrutura Molecular , Espectrometria por Raios X , Difração de Raios X
7.
Scand J Psychol ; 61(3): 402-409, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32207859

RESUMO

This study applies an intervention based on autonomy support through dialogic learning to examine effects on motivation and the promotion of physical activity and sport involvement during schoolchildren's leisure time. One hundred and two primary school students, aged 11-13 years, participated (M = 10.93, SD = 0.75). The sample was divided into two groups: an experimental group (49 students) and a control group (53 students). A quasi-experimental study was conducted in physical education classes over the course of 9 months. Assessments of autonomy support from teachers, family, and peers; basic psychological needs; self-determined motivation in physical education and during leisure time; planned behavior variables; physical activity intention; and estimated and actual physical exercise behavior time were included in the model. Following the intervention, the results revealed that greater autonomy support by the teacher, the family and peers, satisfaction of the basic psychological needs, self-determined motivation during physical education class and during free time, greater perceived control, favorable attitude and intention to engage in physical activity contributed to the explanation of student physical activity involvement. These results suggest that when students receive extensive social support from diverse social agents that essential precursors to physical activity are strengthened and contribute to increased motivation and actual physical activity involvement. Efforts to promote effective communications with students and other pedagogical efforts, such as providing dialogic learning opportunities, should be considered in order to strengthen physical activity motivation and involvement in students.


Assuntos
Exercício Físico/psicologia , Motivação , Satisfação Pessoal , Apoio Social , Adolescente , Criança , Feminino , Humanos , Intenção , Masculino , Influência dos Pares , Autonomia Pessoal , Educação Física e Treinamento/métodos , Esportes/psicologia , Estudantes/psicologia
8.
Inorg Chem ; 56(19): 11810-11818, 2017 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-28920677

RESUMO

The use of theoretical calculations has allowed us to predict the coordination behavior of dithiolene [M(SC6H4S)2]2- (M = Ni, Pd, Pt) entities, giving rise to the first organometallic polymers {[K2(µ-H2O)2][Ni(SC6H4S)2]}n and {[K2(µ-H2O)2(thf)]2[K2(µ-H2O)2(thf)2][Pd3(SC6H4S)6]}n by one-pot reactions of the corresponding d10 metal salts, 1,2-benzenedithiolene, and KOH. The polymers are based on σ,π interactions between potassium atoms and [M(SC6H4S)2]2- (M = Ni, Pd) entities. In contrast, only σ interactions are observed when the analogous platinum derivative is used instead, yielding the coordination polymer {[K2(µ-thf)2][Pt(SC6H4S)2]}n.

9.
Inorg Chem ; 54(5): 2243-52, 2015 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-25667965

RESUMO

Coordination polymer chains have been formed by the direct reaction between HSC6H2Cl2SH and FeCl3·6H2O in the presence of an aqueous solution of the corresponding alkali-metal hydroxide (M = Li, Na, and K) or carbonate (M = Rb and Cs). The structures consist of dimeric [Fe2(SC6H2Cl2S)4](2-) entities bridged by [M2(THF)4] [M = K (1), Rb (2), and Cs (3); THF = tetrahydrofuran] or {[Na2(µ-H2O)2(THF)2] (5 and 5') units. The smaller size of the lithium atom yields an anion/cation ion-pair molecule, [Li(THF)4]2[Fe2(SC6H2Cl2S)4] (4), in which the dianionic moieties are held together by Cl···Cl interactions. Electrical characterization of these compounds shows a general semiconductor behavior in which the conductivity and activation energies are mainly determined by the M-Cl and M-S bond distances. Compounds 1 and 5' are interesting examples of bistability showing reversible transitions centered at ca. 350 and 290 K with very large hysteresis of ca. 60 and 35 K, respectively. All of these compounds exhibit intradimer strong antiferromagnetic Fe···Fe interactions.


Assuntos
Compostos Ferrosos/química , Metais Alcalinos/química , Polímeros/química , Compostos de Sulfidrila/química , Temperatura , Condutividade Elétrica , Modelos Moleculares , Semicondutores
10.
JCO Glob Oncol ; 10: e2400008, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39208384

RESUMO

PURPOSE: Although the intestinal subtype of gastric cancer (GC) is most prevalent around the world, a relatively high prevalence of the diffuse subtype has been reported in some populations of Central American countries, including Guatemala. This study aimed to investigate whether differences exist in the prevalence of the two GC subtypes in the two main ethnic groups in Guatemala, namely Mayan and Mestizo (known as Ladino in Guatemala), between whom significant socioeconomic disparities exist, and to determine whether there is an association with Helicobacter pylori/CagA seropositivity. MATERIALS AND METHODS: Participants included 65 patients with GC and 135 age-/sex-matched controls. Data on ethnicity, H. pylori and CagA seropositivity status, as well as tumor subtype (diffuse or intestinal) were collected. Logistic regression models were fitted to examine the relationship between predictor variables (age, sex, ethnicity, H. pylori, and CagA) and the binary response variable (tumor type). Model selection was based on the Akaike information criterion. RESULTS: The prevalence of diffuse GC was found to be significantly higher in the Mayan compared with the Mestizo population in Guatemala. Although seropositivity for CagA was significantly higher in patients with GC, there were no significant differences between the two GC subtypes. CONCLUSION: This study suggests that there are differences in the prevalence of intestinal and diffuse GC histologic subtypes between the two main ethnic groups in Guatemala. Further studies are warranted, given the potential higher prevalence of the more severe GC subtype in the most vulnerable population.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/microbiologia , Guatemala/epidemiologia , Feminino , Masculino , Pessoa de Meia-Idade , Prevalência , Helicobacter pylori/isolamento & purificação , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/complicações , Idoso , Adulto , Antígenos de Bactérias
11.
Pediatr Res ; 73(5): 674-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23403803

RESUMO

BACKGROUND: Subclinical hypothyroidism (SH), defined as mild thyroid-stimulating hormone (TSH) elevation with normal free thyroxine (FT4) levels and no symptoms, is common during the first few years of life in Down syndrome (DS) and can be self-limiting. Our objective was to confirm that SH is usually a transitory disorder and to identify the factors associated with spontaneous remission. METHODS: We reviewed clinical histories of patients from the Catalan Down Syndrome Foundation (CDSF) with DS and SH diagnosed before 5 y of age. SH was defined as TSH 5.5-25 µU/ml (6 mo-4 y) or 4.13-25 µU/ml (4-7 y), with FT4 0.89-1.87 ng/dl (6 mo-4 y) or 0.96-1.86 ng/dl (4-7 y). RESULTS: Fifty-three patients with SH were identified, with an average age of 2.4 ± 1.1 y, median (range) TSH at diagnosis 7.1 (4.2-23.9 µU/ml), and median (range) FT4 1.1 (0.9-1.7 ng/dl). SH resolved spontaneously in 39 cases (73.6%), with TSH at the most recent visit (mean age 6.7 ± 1.4 y) 3.9 (1.8-12.7 µU/ml). The rate of remission was significantly higher in patients without goiter (94.9 vs. 28.6%) and in those who were negative for antithyroid antibodies (89.7 vs. 42.9%). CONCLUSION: SH in infants and preschool children with DS is usually a transitory disorder, with remission in >70% of cases. The absence of goiter and thyroid autoantibodies was associated with a greater rate of spontaneous remission in our study.


Assuntos
Síndrome de Down/complicações , Hipotireoidismo/complicações , Pré-Escolar , Humanos , Lactente
12.
Inorg Chem ; 52(10): 5943-50, 2013 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-23634881

RESUMO

The synthesis, crystal structure, and physical properties of an unprecedented one-dimensional (1D) coordination polymer containing [Fe2(S2C6H2Cl2)4](2-) entities bridged by dicationic [K2(µ-H2O)2(THF)4](2+) units are described. The magnetic properties show that the title compound presents pairwise Fe-Fe antiferromagnetic interactions that can be well reproduced with a S = 1/2 dimer model with an exchange coupling, J = -23 cm(-1). The electrical conductivity measurements show that the title compound is a semiconductor with an activation energy of about 290 meV and two different transitions, both with large hysteresis of about 60 and 30 K at 260-320 K and 350-380 K, respectively. These two transitions are assumed to be due to slight structural changes in the cation-anion interactions. Differential Scanning Calorimetry confirms the presence of both transitions. This compound represents the first sample of a coordination polymer showing electrical bistability.


Assuntos
Compostos Organometálicos/química , Polímeros/química , Temperatura , Varredura Diferencial de Calorimetria , Elétrons , Campos Magnéticos , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química
13.
J Sports Sci Med ; 12(3): 551-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24149164

RESUMO

The aim of this study was to establish motivational profiles for doing physical activity according to the variables from the theory of planned action in a sample of 698 students aged 14 to 16. The instruments used were the Questionnaire of Behavioral Regulation in Sport (BRQ-R) and the Questionnaire of the Theory of Planned Behavior (TCP). Cluster analysis revealed two motivational profiles: a "self-determined "profile with high scores in intrinsic motivation and low scores in extrinsic motivation and amotivation, and a "non self- determined "profile with low scores in intrinsic motivation and high scores in extrinsic motivation and amotivation. Positive significant differences in attitudes, norms, and intent to control were found for the self-determined profile related to "non self-determined "profile. Key PointsA "self-determined "profile was found with higher scores for the four types of intrinsic motivations (general, knowledge, stimulation and achievement) and identified regulation than for introjected and external regulation.A "non self-determined "profile was found with higher scores for external, introjected regulation and amotivation than for the four types of intrinsic motivation (general, knowledge, stimulation and achievement).In the context of the "non self-determined profile "we could encourage programs that adapt to these needs in such a way that they contribute to increasing the rates of doing physical activity in the population.

14.
PLoS One ; 17(4): e0266039, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35421100

RESUMO

The purpose of this study was to examine relationships among instructor autonomy support for student learning, and students' motivational characteristics, learning approaches, perceptions of career competence and life satisfaction. Participated 1048 students from Spanish universities with ages between 18, and 57 years. A Structural equation modeling revealed a relationship between instructor autonomy support for student learning with students' basic psychological need satisfaction. As a result, students' basic need satisfaction was related to their intrinsic motivation, and to a deeper learning approach. These educational outcomes contributed to explain students'perceived professional competence, and life satisfaction. These findings highlight the importance of student choice, and decision-making in the learning process as a means to facilitating deeper learning, stronger feelings of professional competence, and enhanced well-being.


Assuntos
Motivação , Satisfação Pessoal , Humanos , Autonomia Pessoal , Competência Profissional , Estudantes/psicologia , Universidades
15.
Hum Immunol ; 83(11): 741-748, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36028459

RESUMO

Guatemala is a country located in Central America, and while it is one of the most populated countries in the region, the genetic diversity of the population has been poorly analyzed. Currently, there are no analyses of the distribution of human leukocyte antigen (HLA) system alleles in mixed ancestry (i.e., ladino) populations in Guatemala. The HLA system exhibits the most extensive polymorphism in the human genome and has been extensively analyzed in a large number of studies related to disease association, transplantation, and population genetics (with particular importance in the understanding of diversity in the human population). Here, we present HLA typing data from 127 samples of unrelated individuals from the kidney transplant program of the San Juan de Dios General Hospital (Guatemala City) using a PCR-SSOP-based (PCR-sequence specific oligonucleotide probes) typing method. We found 16 haplotypes that accounted for 39.76 % of the total haplotype diversity, of which thirteen have been reported previously in Native American populations and three have been reported in European populations. The analyses showed no deviations from Hardy-Weinberg equilibrium, and admixture estimates calculated with k = 3 ancestral components showed that Native American was the most represented component, followed by the European component. The African component was less prominent in the Guatemala mixed ancestry sample in comparison to samples from other countries in Central America. The HLA-based admixture results for Central America showed a continuum in the distribution of Native American, European and African ancestries throughout the region, which is consistent with the complex demographic history of the region.


Assuntos
Transplante de Rim , Alelos , Frequência do Gene , Variação Genética , Genética Populacional , Guatemala , Antígenos HLA/genética , Haplótipos , Humanos , Desequilíbrio de Ligação , México , Sondas de Oligonucleotídeos
16.
Int J Primatol ; 43(2): 291-316, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35043025

RESUMO

When studying animal behavior in the wild, some behaviors may require observation from a relatively short distance. In these cases, habituation is commonly used to ensure that animals do not perceive researchers as a direct threat and do not alter their behavior in their presence. However, habituation can have significant effects on the welfare and conservation of the animals. Studying how nonhuman primates react to the process of habituation can help to identify the factors that affect habituation and implement habituation protocols that allow other researchers to speed up the process while maintaining high standards of health and safety for both animals and researchers. In this study, we systematically described the habituation of two groups of wild moor macaques (Macaca maura), an Endangered endemic species of Sulawesi Island (Indonesia), to assess the factors that facilitate habituation and reduce impact on animal behavior during this process. During 7 months, we conducted behavioral observations for more than 7,872 encounters and an average of 120 days to monitor how macaque behavior toward researchers changed through time in the two groups under different conditions. We found that both study groups (N = 56, N = 41) became more tolerant to the presence of researchers during the course of the habituation, with occurrence of neutral group responses increasing, and minimum distance to researchers and occurrence of fearful group responses decreasing through time. These changes in behavior were predominant when macaques were in trees, with better visibility conditions, when researchers maintained a longer minimum distance to macaques and, unexpectedly, by the presence of more than one researcher. By identifying these factors, we contribute to designing habituation protocols that decrease the likelihood of fearful responses and might reduce the stress experienced during this process.

17.
Meat Sci ; 175: 108454, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33548841

RESUMO

The aim was to study biophysical and chemical changes during low-temperature long-time (LTLT) heat treatment of pork by measuring cathepsin B+L activity, surface hydrophobicity of myofibrils, particle size of myofibrils and effect on meat toughness as indicated by Allo-Kramer shear force. Longissimus thoracis et lumborum muscles were divided into large pieces, vacuum packaged and cooked in water baths at 53, 58, 63, 68 and 73 °C for 1, 8 and 24 h. The results showed that the meat toughness was markedly lower at temperatures of 53 °C and 58 °C and decreased with increasing holding time. Myofibrillar surface hydrophobicity increased with temperature, but not with time, indicating aggregation and/or gelation phenomena took place. Treatments with the lowest shear force values generally had smaller particles and were associated with high cathepsin B+L activity. A mechanism by which these cathepsins might affect the aggregation dynamics and change the mechanical properties of meat is proposed.


Assuntos
Catepsina B/análise , Catepsina L/análise , Culinária/métodos , Proteínas Musculares/química , Carne de Porco/análise , Animais , Músculo Esquelético/química , Miofibrilas/química , Resistência ao Cisalhamento , Suínos , Temperatura , Fatores de Tempo , Vácuo
18.
Front Psychol ; 12: 626786, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33995182

RESUMO

The traditional teaching style in which the teacher is in control and there is a submissive attitude in students is predominant in Mexico. The development of identity in preadolescence is subjected to social groups, which could develop interpersonal difficulties through the controlling teaching style. Although the fear of negative evaluation in students and competitive sport has been studied in education, relatively little research has been done in the area of physical education in relation to the controlling style. The purpose of this study was to investigate the correlation and predictive relationship between controlling teaching and the fear of negative evaluation mediated by the frustration of the basic psychological needs (BPN), controlled motivation, and individualism/competitiveness through the theoretical framework of self-determination theory. Participants were 1132 students in the fifth and sixth grades in public elementary schools in the state of Chihuahua, Mexico, with ages between 10 and 13 (M = 10.51 years; SD = 0.66 years). Results indicate the perceived controlling teaching style positively predicted the fear of negative evaluation in students of this study through BPN frustration, that is positively related to low-quality motivation, which is related to a higher level of individualism/competitiveness. This, in turn, is proven to be a predictor of the fear of negative evaluation. The results also discuss the promotion of the autonomy support style, avoiding the controlling teaching style, for the minimization of negative results related to the perception of fear and the development of student well-being both within and beyond the school context.

19.
PLoS One ; 15(6): e0235011, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32579576

RESUMO

A growing body of research-based knowledge has been generated for the purpose of better understanding the reciprocal and dynamic relationship between teachers' instructional characteristics and students' psychosocial and learning outcomes. This study specifically examined the relationship between teachers' interpersonal styles and fear of failure outcomes in physical education students. Five hundred sixty-two middle school and high school students in Physical Education classes (PE) participated in the study. Students completed questionnaires that assessed instructors' autonomy-supportive and controlling teaching styles and students' own fear of failure. A person-centered analysis was used to test the hypotheses. The results revealed that higher teacher autonomy support was associated with lower student fear of failure. To the contrary, a controlling teaching style was associated with fear of failure in these students. Two profiles emerged in which moderate fear of failure was associated with a stronger perception of a controlling teacher style and lower levels of fear of failure were associated with greater perceived instructor support for autonomy.


Assuntos
Medo/psicologia , Educação Física e Treinamento , Professores Escolares , Estudantes/psicologia , Adolescente , Análise por Conglomerados , Humanos
20.
Artigo em Inglês | MEDLINE | ID: mdl-32858995

RESUMO

(1) Background: The aim of this study was to design and analyze the validity of the SMACC (Scale to Measure Aquatic Competence in Children) to evaluate aquatic competence in three- to six-year-old children. In addition, the relation between real competence obtained with the SMACC and perceived aquatic competence was verified as well as its differences according to sex and age. (2) Methods: Content validation was performed through the consensus of nine experts using the Delphi technique, and comprehension validity was determined through a pilot study on a sample of 122 children. An exploratory and confirmatory factor analysis was performed with two independent samples of 384 and 444 school children between three and six years old, respectively. (3) Results: After the pertinent adjustments, the final questionnaire comprised 17 items, which showed a good fit for both comprehension and content validity. The results of the exploratory and confirmatory analyses support the use of three dimensions in aquatic competence: motor, socio-affective, and cognitive. The correlations support construct validity showing a positive relation with perceived aquatic competence. (4) Conclusions: These promising validity data are discussed from a global and integrative perspective in relation to the improvement of children's development in the aquatic environment during the early stages of their lives.


Assuntos
Desenvolvimento Infantil , Destreza Motora , Inquéritos e Questionários/normas , Natação , Criança , Pré-Escolar , Análise Fatorial , Humanos , Projetos Piloto , Psicometria/instrumentação , Psicometria/estatística & dados numéricos , Reprodutibilidade dos Testes , Água
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