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1.
J Affect Disord ; 357: 148-155, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38670463

RESUMEN

BACKGROUND: Anxiety disorders are among the most common mental health disorders in the middle aged and older population. Because older individuals are more likely to have multiple comorbidities or increased frailty, the impact of anxiety disorders on their overall well-being is exacerbated. Early identification of anxiety disorders using machine learning (ML) can potentially mitigate the adverse consequences associated with these disorders. METHODS: We applied ML to the data from the Canadian Longitudinal Study on Aging (CLSA) to predict the onset of anxiety disorders approximately three years in the future. We used Shapley value-based methods to determine the top factor for prediction. We also investigated whether anxiety onset can be predicted by baseline depression-related predictors alone. RESULTS: Our model was able to predict anxiety onset accurately (Area under the Receiver Operating Characteristic Curve or AUC = 0.814 ± 0.016 (mean ± standard deviation), balanced accuracy = 0.741 ± 0.016, sensitivity = 0.743 ± 0.033, and specificity = 0.738 ± 0.010). The top predictive factors included prior depression or mood disorder diagnosis, high frailty, anxious personality, and low emotional stability. Depression and mood disorders are well known comorbidity of anxiety; however a prior depression or mood disorder diagnosis could not predict anxiety onset without other factors. LIMITATION: While our findings underscore the importance of a prior depression diagnosis in predicting anxiety, they also highlight that it alone is inadequate, signifying the necessity to incorporate additional predictors for improved prediction accuracy. CONCLUSION: Our study showcases promising prospects for using machine learning to develop personalized prediction models for anxiety onset in middle-aged and older adults using easy-to-access survey data.


Asunto(s)
Trastornos de Ansiedad , Aprendizaje Automático , Humanos , Femenino , Masculino , Canadá/epidemiología , Estudios Longitudinales , Anciano , Trastornos de Ansiedad/epidemiología , Trastornos de Ansiedad/diagnóstico , Trastornos de Ansiedad/psicología , Persona de Mediana Edad , Envejecimiento/psicología , Anciano de 80 o más Años , Depresión/epidemiología , Depresión/diagnóstico , Depresión/psicología , Comorbilidad , Fragilidad/diagnóstico , Fragilidad/epidemiología , Estudios Prospectivos , Ansiedad/epidemiología , Ansiedad/diagnóstico , Ansiedad/psicología
2.
Entropy (Basel) ; 26(3)2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38539754

RESUMEN

Using electroencephalogram (EEG), we tested the hypothesis that the association of a neutral stimulus with the self would elicit ultra-fast neural responses from early top-down feedback modulation to late feedforward periods for cognitive processing, resulting in self-prioritization in information processing. In two experiments, participants first learned three associations between personal labels (self, friend, stranger) and geometric shapes (Experiment 1) and three colors (Experiment 2), and then they judged whether the shape/color-label pairings matched. Stimuli in Experiment 2 were shown in a social communicative setting with two avatars facing each other, one aligned with the participant's view (first-person perspective) and the other with a third-person perspective. The color was present on the t-shirt of one avatar. This setup allowed for an examination of how social contexts (i.e., perspective taking) affect neural connectivity mediating self-related processing. Functional connectivity analyses in the alpha band (8-12 Hz) revealed that self-other discrimination was mediated by two distinct phases of neural couplings between frontal and occipital regions, involving an early phase of top-down feedback modulation from frontal to occipital areas followed by a later phase of feedforward signaling from occipital to frontal regions. Moreover, while social communicative settings influenced the later feedforward connectivity phase, they did not alter the early feedback coupling. The results indicate that regardless of stimulus type and social context, the early phase of neural connectivity represents an enhanced state of awareness towards self-related stimuli, whereas the later phase of neural connectivity may be associated with cognitive processing of socially meaningful stimuli.

3.
Int J Biol Macromol ; 254(Pt 2): 127323, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37879577

RESUMEN

The study examined the impact of phase morphological transformations within the corn starch/gelatin system, induced by varying gelatin content, on its rheological properties and 3D printing performance. Gelatin addition inhibited the gelatinization and retrogradation of starch, which leaded to the transformation of continuous phase structure. The transition process from starch continuous phase to gelatin continuous phase promoted a thinner wall structure of the gel and loosed its dense network, resulting in reduced flow stress (τf) and storage modulus (G'). These changes improved the extrusion and "extrusion swelling" of gel ink materials, which made the print size of printed product closer to the set model. The formation of a gelatin continuous phase in the gel was helpful in increasing τf and G', resulting in enhanced support capacity of the printed product. This study presented meaningful information for the application of 3D printing to starch-gelatin complex foods.


Asunto(s)
Gelatina , Almidón , Almidón/química , Gelatina/química , Zea mays , Alimentos , Impresión Tridimensional
4.
Br J Psychol ; 115(2): 185-205, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37747452

RESUMEN

Our everyday perceptual experiences are grounded in the integration of information within and across our senses. Due to this direct behavioural relevance, cross-modal integration retains a certain degree of contextual flexibility, even to social relevance. However, how social relevance modulates cross-modal integration remains unclear. To investigate possible mechanisms, Experiment 1 tested the principles of audio-visual integration for numerosity estimation by deriving a Bayesian optimal observer model with perceptual prior from empirical data to explain perceptual biases. Such perceptual priors may shift towards locations of high salience in the stimulus space. Our results showed that the tendency to over- or underestimate numerosity, expressed in the frequency and strength of fission and fusion illusions, depended on the actual event numerosity. Experiment 2 replicated the effects of social relevance on multisensory integration from Scheller & Sui, 2022 JEP:HPP, using a lower number of events, thereby favouring the opposite illusion through enhanced influences of the prior. In line with the idea that the self acts like a prior, the more frequently observed illusion (more malleable to prior influences) was modulated by self-relevance. Our findings suggest that the self can influence perception by acting like a prior in cue integration, biasing perceptual estimates towards areas of high self-relevance.


Asunto(s)
Ilusiones , Humanos , Percepción Visual , Percepción Auditiva , Teorema de Bayes , Estimulación Acústica , Estimulación Luminosa
5.
Cogn Res Princ Implic ; 8(1): 70, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37991559

RESUMEN

The self, like the concept of central "gravity", facilitates the processing of information that is directly relevant to the self. This phenomenon is known as the self-prioritization effect. However, it remains unclear whether the self-prioritization effect extends to the processing of emotional facial expressions. To fill this gap, we used a self-association paradigm to investigate the impact of self-relevance on the recognition of emotional facial expressions while controlling for confounding factors such as familiarity and overlearning. Using a large and diverse sample, we replicated the effect of self-relevance on face processing but found no evidence for a modulation of self-relevance on facial emotion recognition. We propose two potential theoretical explanations to account for these findings and emphasize that further research with different experimental designs and a multitasks measurement approach is needed to understand this mechanism fully. Overall, our study contributes to the literature on the parallel cognitive processing of self-relevance and facial emotion recognition, with implications for both social and cognitive psychology.


Asunto(s)
Expresión Facial , Reconocimiento Facial , Emociones , Reconocimiento en Psicología , Proyectos de Investigación
6.
J Orthop Surg Res ; 18(1): 762, 2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37814350

RESUMEN

Several members of the ubiquitin-specific proteases (USPs) family have been revealed to regulate the progression of osteoarthritis (OA). The current study aimed to investigate the role and the underlying mechanism of USP25 in IL-1ß-induced chondrocytes and OA rat model. It was discovered that IL-1ß stimulation upregulated USP25, increased ROS level, and suppressed cell viability in rat chondrocytes. Besides, USP25 knockdown alleviated IL-1ß-induced injury by decreasing ROS level, attenuating pyroptosis, and downregulating the expression of IL-18, NLRP3, GSDMD-N, active caspase-1, MMP-3, and MMP-13. Furthermore, we discovered that USP25 affected the IL-1ß-induced injury in chondrocytes in a ROS-dependent manner. Moreover, USP25 was revealed to interact with TXNIP, and USP25 knockdown increased the ubiquitination of TXNIP. The pro-OA effect of USP25 abundance could be overturned by TXNIP suppression in IL-1ß-induced chondrocytes. Finally, in vivo experiment results showed that USP25 inhibition alleviated cartilage destruction in OA rats. In conclusion, we demonstrated that USP25 stimulated the overproduction of ROS to activate the NLRP3 inflammasome via regulating TXNIP, resulting in increased pyroptosis and inflammation in OA.


Asunto(s)
Inflamasomas , Osteoartritis , Animales , Ratas , Proteínas de Ciclo Celular , Inflamasomas/metabolismo , Inflamación/metabolismo , Interleucina-1beta/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Osteoartritis/metabolismo , Especies Reactivas de Oxígeno/metabolismo
8.
Cognition ; 240: 105600, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37604029

RESUMEN

There is abundant evidence of a self-bias in cognition, with prioritised processing of information that is self-relevant. There is also abundant evidence of a positivity-bias in cognition, with prioritised processing of information that is positively valenced (e.g., positive emotional expressions, rewards). While the effects of self-bias and positivity-bias have been well documented in isolation, they have seldom been examined in parallel, so it is unclear whether one or other of these stimulus classes is prioritised or whether they interact. Addressing this gap, the current research aimed to establish the relative primacy of self-bias and positivity-bias using a classification task that paired self-relevant information with emotional expressions (i.e., Expt. 1) or reward information (i.e., Expt. 2). When the self was paired with relatively more positive information (i.e., smiling faces or high reward) we found evidence of a self-bias but no evidence of a positivity-bias. Whereas when the self was paired with relatively less positive information (i.e., neutral faces or low reward) we found evidence of a positivity-bias but no evidence of a self-bias. These results suggest the relative primacy of prioritised processing is flexible, context dependent and might be caused by a drive towards self-enhancement and the self-positivity bias.


Asunto(s)
Cognición , Recompensa , Humanos , Sesgo
9.
J Affect Disord ; 339: 52-57, 2023 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-37380110

RESUMEN

BACKGROUND: Early identification of the middle-aged and elderly people with high risk of developing depression disorder in the future and the full characterization of the associated risk factors are crucial for early interventions to prevent depression among the aging population. METHODS: Canadian Longitudinal Study on Aging (CLSA) has collected comprehensive information, including psychological scales and other non-psychological measures, i.e., socioeconomic, environmental, health, lifestyle, cognitive function, personality, about its participants (30,097 subjects aged from 45 to 85) at baseline phase in 2012-2015. We applied machine learning models for the prediction of these participants' risk of depression onset approximately three years later using information collected at baseline phase. RESULTS: Individual-level risk for future depression onset among CLSA participants can be accurately predicted, with an area under receiver operating characteristic curve (AUC) 0.791 ± 0.016, using all baseline information. We also found the 10-item Center for Epidemiological Studies Depression Scale coupled with age and sex information could achieve similar performance (AUC 0.764 ± 0.016). Furthermore, we identified existing subthreshold depression symptoms, emotional instability, low levels of life satisfaction, perceived health, and social support, and nutrition risk as the most important predictors for depression onset independent from psychological scales. LIMITATIONS: Depression was based on self-reported doctor diagnosis and depression screening tool. CONCLUSIONS: The identified risk factors will further improve our understanding of the depression onset among middle-aged and elderly population and the early identification of high-risk subjects is the first step for successful early interventions.


Asunto(s)
Envejecimiento , Depresión , Persona de Mediana Edad , Humanos , Adulto , Anciano , Estudios Longitudinales , Depresión/diagnóstico , Depresión/epidemiología , Depresión/psicología , Canadá/epidemiología , Envejecimiento/psicología , Aprendizaje Automático
10.
Neuroimage ; 276: 120205, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37253415

RESUMEN

Although the self has traditionally been viewed as a higher-order mental function by most theoretical frameworks, recent research advocates a fundamental self hypothesis, viewing the self as a baseline function of the brain embedded within its spontaneous activities, which dynamically regulates cognitive processing and subsequently guides behavior. Understanding this fundamental self hypothesis can reveal where self-biased behaviors emerge and to what extent brain signals at rest can predict such biased behaviors. To test this hypothesis, we investigated the association between spontaneous neural connectivity and robust self-bias in a perceptual matching task using resting-state functional magnetic resonance imaging (fMRI) in 348 young participants. By decoding whole-brain connectivity patterns, the support vector regression model produced the best predictions of the magnitude of self-bias in behavior, which was evaluated via a nested cross-validation procedure. The out-of-sample generalizability was further authenticated using an external dataset of older adults. The functional connectivity results demonstrated that self-biased behavior was associated with distinct connections between the default mode, cognitive control, and salience networks. Consensus network and computational lesion analyses further revealed contributing regions distributed across six networks, extending to additional nodes, such as the thalamus, whose role in self-related processing remained unclear. These results provide evidence that self-biased behavior derives from spontaneous neural connectivity, supporting the fundamental self hypothesis. Thus, we propose an integrated neural network model of this fundamental self that synthesizes previous theoretical models and portrays the brain mechanisms by which the self emerges at rest internally and regulates responses to the external environment.


Asunto(s)
Conectoma , Humanos , Anciano , Conectoma/métodos , Individualidad , Imagen por Resonancia Magnética/métodos , Encéfalo/fisiología , Procesos Mentales , Red Nerviosa/fisiología , Vías Nerviosas/fisiología
11.
Conscious Cogn ; 108: 103475, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36709725

RESUMEN

Personally relevant stimuli exert a powerful influence on social cognition. What is not yet fully understood, however, is how early in the processing stream self-relevance influences decisional operations. Here we used a shape-label matching task in conjunction with electroencephalography and computational modeling to explore this issue. A theoretically important pattern of results was observed. First, a standard self-prioritization effect emerged indicating that responses to self-related items were faster and more accurate than responses to other-related stimuli. Second, a hierarchical drift diffusion model analysis revealed that this effect was underpinned by the enhanced uptake of evidence from self-related stimuli. Third, self-other discrimination during matching trials was observed at both early posterior N1 and late centro-parietal P3 components. Fourth, whereas the N1 was associated with the rate of information accumulation during decisional processing, P3 activity was linked with the evidential requirements of response selection. These findings elucidate the electrophysiological correlates of self-prioritization.


Asunto(s)
Electroencefalografía , Cognición Social , Humanos
12.
Psychol Med ; 53(5): 1924-1936, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-34488919

RESUMEN

BACKGROUND: Depression is characterised by a heightened self-focus, which is believed to be associated with differences in emotion and reward processing. However, the precise relationship between these cognitive domains is not well understood. We examined the role of self-reference in emotion and reward processing, separately and in combination, in relation to depression. METHODS: Adults experiencing varying levels of depression (n = 144) completed self-report depression measures (PHQ-9, BDI-II). We measured self, emotion and reward processing, separately and in combination, using three cognitive tasks. RESULTS: When self-processing was measured independently of emotion and reward, in a simple associative learning task, there was little association with depression. However, when self and emotion processing occurred in combination in a self-esteem go/no-go task, depression was associated with an increased positive other bias [b = 3.51, 95% confidence interval (CI) 1.24-5.79]. When the self was processed in relation to emotion and reward, in a social evaluation learning task, depression was associated with reduced positive self-biases (b = 0.11, 95% CI 0.05-0.17). CONCLUSIONS: Depression was associated with enhanced positive implicit associations with others, and reduced positive learning about the self, culminating in reduced self-favouring biases. However, when self, emotion and reward processing occurred independently there was little evidence of an association with depression. Treatments targeting reduced positive self-biases may provide more sensitive targets for therapeutic intervention and potential biomarkers of treatment responses, allowing the development of more effective interventions.


Asunto(s)
Depresión , Emociones , Adulto , Humanos , Depresión/psicología , Emociones/fisiología , Recompensa , Aprendizaje , Autoinforme
13.
Q J Exp Psychol (Hove) ; 76(4): 942-960, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35543595

RESUMEN

People show systematic biases in perception, memory, attention, and decision-making to prioritise information related to self, reward, and positive emotion. A long-standing set of experimental findings points towards putative common properties of these effects. However, the relationship between them remains largely unknown. Here, we addressed this question by assessing and linking these prioritisation effects generated by a common associative matching procedure in three experiments. Self, reward, and positive emotion prioritisation effects were assessed using cluster and shift function analyses to explore and test associations between these effects across individuals. Cluster analysis revealed two distinct patterns of the relationship between the biases. Individuals with faster responses showed a smaller reward and linear positive association between reward and emotion biases. Individuals with slower responses demonstrated a large reward and no association between reward and emotion biases. No evidence of the relationship between self and value-based reward or positive emotion prioritisation effects was found among the clusters. A shift function indicated a partial dominance of high-reward over low-reward distributions at later processing stages in participants with slower but not faster responses. Full stochastic dominance of self-relevance over others and positive over neutral emotion was pertinent to each subgroup of participants. Our findings suggest the independent origin of the self-prioritisation effect. In contrast, commonalities in cognitive mechanisms supporting value-based reward and positive emotion processing are subject to individual differences. These findings add important evidence to a steadily growing research base about the relationship between basic behavioural drivers.


Asunto(s)
Atención , Emociones , Humanos , Emociones/fisiología , Recompensa , Sesgo
14.
J Psychopharmacol ; 37(3): 303-312, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36000259

RESUMEN

BACKGROUND: Antidepressants are proposed to work by increasing sensitivity to positive versus negative information. Increasing positive affective learning within social contexts may help remediate negative self-schema. We investigated the association between change in biased learning of social evaluations about the self and others, and mood during early antidepressant treatment. METHOD: Prospective cohort assessing patients recruited from primary care in South West England at four timepoints over the first 8 weeks of antidepressant treatment (n = 29). At each timepoint, participants completed self-report measures of depression (Beck Depression Inventory II (BDI-II) and Patient Health Questionnaire 9 (PHQ-9)), anxiety (Generalised Anxiety Disorder Questionnaire 7 (GAD-7)), and a computerised task measuring learning of social evaluations about the self, a friend and a stranger. RESULTS: We did not find evidence that learning about the self was associated with a reduction in PHQ-9 (b = 0.08, 95% CI: -0.05, 0.20, p = 0.239) or BDI-II scores (b = 0.10, 95% CI: -0.18, 0.38, p = 0.469). We found some weak evidence that increased positive learning about the friend was associated with a reduction in BDI-II scores (b = 0.30, 95% CI: -0.02, 0.62, p = 0.069). However, exploratory analyses indicated stronger evidence that increased positive learning about the self (b = 0.18, 95% CI: 0.07, 0.28, p = 0.002) and a friend (b = 0.22, 95% CI: 0.10, 0.35, p = 0.001) was associated with reductions in anxiety. CONCLUSIONS: Change in social evaluation learning was associated with a reduction in anxiety but not depression. Antidepressants may treat anxiety symptoms by remediating negative affective biases towards socially threatening information directed towards the self and close others. However, our findings are based on exploratory analyses within a small sample without a control group and are therefore at risk of type 1 errors and order effects. Further research with larger samples is required.


Asunto(s)
Afecto , Antidepresivos , Humanos , Estudios Prospectivos , Antidepresivos/uso terapéutico , Ansiedad/tratamiento farmacológico , Atención Primaria de Salud
15.
Conscious Cogn ; 107: 103451, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36463796

RESUMEN

Previous research suggests that attention is drawn by self-related information. Three online experiments were conducted to investigate whether self-related stimuli alter visuospatial perceptual judgments. In a matching task, associations were learned between labels ('Yourself'/friend/stranger's name) paired with cues. Cues were coloured outlines (Experiment 1, N = 135), geometric shapes (Experiment 2, N = 102), or coloured gradients (Experiment 3, N = 110). Visuospatial perception bias was measured with a greyscales task. Cues were presented prior to, and/or alongside greyscales. We hypothesized there would be a bias towards the self-related cue. In all experiments, we found a self-related bias in the matching task. Furthermore, there was an overall leftward visuospatial perceptual bias (pseudoneglect). However, we found anecdotal to moderate evidence for the absence of an effect of self-related cues on visuospatial perception judgments. Although self-related stimuli influence how our attention is oriented to stimuli, attention mechanisms that influence perceptual judgements are seemingly not affected by a self-bias.


Asunto(s)
Lateralidad Funcional , Percepción Visual , Humanos , Estimulación Luminosa , Percepción Espacial , Aprendizaje
16.
Acta Paediatr ; 112(1): 93-99, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36178241

RESUMEN

AIM: To understand why some parents are less sensitive to infant cues than others, we need to understand how healthy parents respond, and how this is influenced by factors such as sleep deprivation. Here, we examined whether sleep deprivation alters the self-infant-prioritisation effect in a population of first-time mothers within their first year of motherhood. METHODS: The study took place at Aarhus University Hospital in Denmark from August 2018 until February 2020. First-time mothers were recruited through Midwife clinics, national and social media. All women completed a perceptual matching task including an infant category. The mothers were divided into two groups depending on their sleep status: below or above 7 h of average night-time sleep, measured with actigraphy. RESULTS: Forty-eight first-time mothers at the age of 29.13 ± 3.87 years were included. In the sleep-deprived group, the infant category was statistically significantly higher in accuracy (p = 0.005) and faster in reaction time (p < 0.001) than all other categories. In contrast, in the non-sleep-deprived group, there was no statistically significant difference between self and infant, neither in accuracy, nor reaction time. CONCLUSION: Sleep-deprived new mothers strongly prioritised infants over self, while non-sleep-deprived new mothers showed no prioritisation of the self over the infant.


Asunto(s)
Madres , Privación de Sueño , Adulto , Femenino , Humanos , Estado de Salud , Padres
17.
Acta Paediatr ; 112(1): 85-92, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36181725

RESUMEN

AIM: This study used a screen-based perceptual matching task to see how non-parents, people trying to get pregnant, and those who had given birth prioritised shapes and labels relating to self or infant conditions. METHODS: The study took place at Aarhus University Hospital in Denmark from December 2016 to November 2021. Recruitment methods included family planning clinics, social media, online recruitment systems and local bulletin boards. The modified perceptual matching task linked five shapes to five labels, including self and infant. RESULTS: We found that 67 males and females with a mean age of 24.4 ± 3 years, who had no plans to become parents in the near future, reacted faster and more accurately to self-shapes and labels (p < 0.001), which validated the experiment. The 56 participants aged 27.1 ± 4.4 years who were actively trying to become parents showed no statistically significant prioritisation. A subset of 21 participants aged 28.7 ± 4.4 years showed faster response times to infant than self-shapes and labels 1 year after giving birth (p < 0.001). CONCLUSION: Healthy first-time parents showed faster reactions to infant than self-conditions 1 year after giving birth, in contrast to the other two groups.


Asunto(s)
Estado de Salud , Padres , Adulto , Femenino , Humanos , Lactante , Embarazo , Adulto Joven
18.
Front Nutr ; 10: 1335812, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38299182

RESUMEN

In this study, thermoplastic starch (TPS) was prepared by melt extrusion process, in which glycerol and/or D-mannitol were used as plasticizers, and the effect of different glycerol/D-mannitol ratios (4:0, 3:1, 2:2, 1:3, and 0:4) on the physicochemical properties of the extruded starch samples was investigated. The short-range molecular order, crystallization, gelatinization, thermal stability, and thermal properties of the TPS samples were analyzed through attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray diffraction (XRD), rapid visco analysis (RVA), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The results showed that the crystallinity and short-range molecular order of the TPS samples increased with increasing glycerol content. Conversely, the water absorption index (WAI) and water solubility index (WSI) of the TPS samples decreased with increasing glycerol content. In addition, the TPS samples with higher glycerol content exhibited higher gel and thermal stabilities. This study provides a theoretical basis for starch extrusion and plasticization in the preparation of TPS-based materials with specific properties.

19.
Front Nutr ; 9: 1052285, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36583213

RESUMEN

In this study, starches were isolated from inbred (sweet and waxy) and hybrid (sweet and waxy) sorghum grains. Structural and property differences between (inbred and hybrid) sweet and waxy sorghum starches were evaluated and discussed. The intermediate fraction and amylose content present in hybrid sweet starch were lower than those in inbred sweet starch, while the opposite trend occurred with waxy starch. Furthermore, there was a higher A chain (30.93-35.73% waxy, 13.73-31.81% sweet) and lower B2 + B3 chain (18.04-16.56% waxy, 24.07-17.43% sweet) of amylopectin in hybrid sorghum starch. X-ray diffraction (XRD) and Fourier transform infrared reflection measurements affirm the relative crystalline and ordered structures of both varieties as follows: inbred waxy > hybrid waxy > hybrid sweet > inbred sweet. Small angle X-ray scattering and 13C CP/MAS nuclear magnetic resonance proved that the amylopectin content of waxy starch was positively correlated with lamellar ordering. In contrast, an opposite trend was observed in sweet sorghum starch due to its long B2 + B3 chain content. Furthermore, the relationship between starch granule structure and function was also concluded. These findings could provide a basic theory for the accurate application of existing sorghum varieties precisely.

20.
Int J Biol Macromol ; 221: 1-7, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36067844

RESUMEN

The effects of shell separation pretreatment (SSP) on the physicochemical properties of octenyl succinic anhydride (OSA)-modified starch were investigated in this study. SSP at different temperatures promoted esterification between starch molecules and OSA and thereby achieved a higher degree of substitution (DS). OSA-modified granule shells (OSCs) exhibited a rough surface and irregular shape, which were attributed to swelling caused by SSP during modification processes. The paste viscosity and viscoelastic properties of OSCs were enhanced after SSP. Both the swelling power and transparency of OSA esterified starch increased with DS values after SSP. The content of resistant starch (RS) among OSA esterified starch increased from 33.18 % to 45.33 %, which mainly occurred when SSP was introduced into the OS starch synthesis process. In summary, SSP at different temperatures promoted the unique physicochemical properties of OSCs specimens by increasing their DS values.


Asunto(s)
Almidón , Anhídridos Succínicos , Almidón/química , Viscosidad , Esterificación , Anhídridos Succínicos/química
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