226 research outputs found

    Neural bruise prediction models for fruit handling and machinery evaluation

    Get PDF
    Neural bruise prediction models based on the degree of fruit damage of the most traded fruit species and varieties were developed for prediction of the fruits to be accepted or rejected. The prediction relied on European Community standards. Different models for both quasi-static (compression) and dynamic (impact) loads covering the full commercial ripening period of fruits were developed. A simulation process was developed for gathering the information on laboratory bruise models and load sensor calibrations for different electronic devices (IS-100 and DEA-1, for impact and compression loads, respectively). An evaluation method was also designed for acquiring and gathering the information on the mechanical properties of fruits and the loading records of the electronic devices. The evaluation system allowed for determination of the current stage of fruit handling processes and machiner

    Modelos de predicción de daños en fruta y sistemática para la evaluación de equipos hortofrutícolas

    Full text link
    Se han desarrollado en laboratorio distintos modelos de predicción de daños, para las especies y variedades más exportadas, con el fin de determinar la pontencial aceptabilidad o rechazo de daños de acuerdo con la normativa comunitaria. Se han desarrollado modelos de predicción para cargas quasi-estáticas (compresiones) y dinámicas (impactos) que abarcan completamente el período de maduración comercial de los frutos. Se ha efectuado un proceso de simulación que integra la información obtenida en laboratorio a través de los modelos de predicción de daños con la correspondiente a la calibración de distintos frutos electrónicos (IS-100 y DEA- 1, para cargas de impacto y compresión respectivamente). Se ha diseñado una metodología de evaluación que recoge tanto las propiedades mecánicas de los frutos en sus dintintos estados de madurez como los registros correspondientes a los frutos electrónicos. La sistemática de evaluación permite determinar el estado actual tanto de la maquinaria como de los procesos de manipulación de fruta

    Sensors for fruit firmness assessment: Comparision and fusion

    Get PDF
    Non-destructive measurement of fruit firmness is a difficult problem and many different sensors have been developed in order to achieve this task. Three different European laboratories were associated in collaborative experiments on peaches, to compare three different sensing techniques, namely, sound, impact and micro-deformation. A Bayesian classifier is associated with each individual sensor and provides a classification into three categories, namely “soft”, “half firm” and “firm”. The fusion of the different sensors is performed by using Bayesian classifiers associated with heuristic methods for identity fusion. The result of the identity fusion is compared with the classification provided by an unsupervised algorithm based on destructive measurements. The fusion process provides some improvement in the classification results. For the individual sensors, the error rate of the classification varied from 19 to 28%, but the fusion process reduced this to 14%. Moreover, all measures of agreement between sensors lead to the conclusion that fusing sensors is better than using individual sensor

    A mathematical model for the development of mealiness in apples

    Get PDF
    Mealiness in apples (Malus domestica Borkh.) is an internal quality defect which is characterised by a dry and crumbly texture. It is related to the relative strength of the cell wall and the middle lamella. A mathematical model has been built to relate changes in the texture attributes juiciness, tensile strength and hardness, which are associated with mealiness, to the development of the turgor pressure of the tissue and the degree of hydrolysis of the middle lamella. The latter, in turn, are described in terms of properties which are meaningful from the physiological point of view, such as starch content, soluble solids content, non-hydrolysed and hydrolysed middle lamella, water in the symplast, and water in the apoplast. Biochemical reactions as well as water transfer processes are incorporated in the model. The parameter values of the model are estimated using experimental data from a storage experiment. The model fits the three texture characteristics adequately. The correlation coefficients between the parameters were below 0.96, which indicates that the model does not overfit the data

    Neural bruise prediction models for fruit handling and machinery evaluation.

    Full text link
    Some neural bruise prediction models have been implemented in the laboratory, for the most traded fruit species and varieties, allowing the prediction of the acceptability or rejectability for damages, with respect to the EC Standards. Different models have been built for both quasi-static (compression) and dynamic (impact) loads covering the whole commercial ripening period of fruits. A simulation process has been developed gathering the information on laboratory bruise models and load sensor calibrations for different electronic devices (IS-100 and DEA-1, for impact and compression loads respectively). Some evaluation methodology has been designed gathering the information on the mechanical properties of fruits and the loading records of electronic devices. The evaluation system allows to determine the current stage of fruit handling process and machinery

    Comparison between sensorial and instrumental measurements for mealiness assessment in apples

    Get PDF
    Definition and establishment of assessment procedures for mealiness of apple fruits using sensory and instrumental measurements were performed on ‘Boskoop', ‘Cox's Orange Pippin’ and ‘Jonagold’ samples with varying degrees of mealiness. The sensory procedure profiled mealiness as a loss of crispness, hardness, and juiciness, with an increase in the floury sensation in the mouth. High correlations between the sensory descriptors and instrumental parameters was shown through principal component analysis. The instrumental procedures (confined compression of fruit cylinders and acoustic impulse response) gave coefficients of determination for juiciness and crispness of 0.85 and 0.71, respectively. This level of accuracy indicates the possibility of establishin

    Amyloid β peptides modify the expression of antioxidant repair enzymes and a potassium channel in the septohippocampal system

    Get PDF
    Alzheimer\u27s disease (AD) is a progressive, neurodegenerative brain disorder characterized by extracellular accumulations of amyloid β (Aβ) peptides, intracellular accumulation of abnormal proteins, and early loss of basal forebrain neurons. Recent studies have indicated that the conformation of Aβ is crucial for neuronal toxicity, with intermediate misfolded forms such as oligomers being more toxic than the final fibrillar forms. Our previous work shows that Aβ blocks the potassium (K(+)) currents IM and IA in septal neurons, increasing firing rates, diminishing rhythmicity and firing coherence. Evidence also suggests that oxidative stress (OS) plays a role in AD pathogenesis. Thus we wished to determine the effect of oligomeric and fibrillar forms of Aβ₁₋₄₂ on septohippocampal damage, oxidative damage, and dysfunction in AD. Oligomeric and fibrillar forms of Aβ₁₋₄₂ were injected into the CA1 region of the hippocampus in live rats. The rats were sacrificed 24 hours and 1 month after Aβ or sham injection to additionally evaluate the temporal effects. The expression levels of the K(+) voltage-gated channel, KQT-like subfamily, member 2 (KCNQ₂) and the OS-related genes superoxide dismutase 1, 8-oxoguanine DNA glycosylase, and monamine oxidase A, were analyzed in the hippocampus, medial, and lateral septum. Our results show that both forms of Aβ exhibit time-dependent differential modulation of OS and K(+) channel genes in the analyzed regions. Importantly, we demonstrate that Aβ injected into the hippocampus triggered changes in gene expression in anatomical regions distant from the injection site. Thus the Aβ effect was transmitted to anatomically separate sites, because of the functional coupling of the brain structures

    Erythroid Differentiation and Heme Biosynthesis Are Dependent on a Shift in the Balance of Mitochondrial Fusion and Fission Dynamics

    Get PDF
    Indexación ScopusErythropoiesis is the most robust cellular differentiation and proliferation system, with a production of ∼2 × 1011 cells per day. In this fine-tuned process, the hematopoietic stem cells (HSCs) generate erythroid progenitors, which proliferate and mature into erythrocytes. During erythropoiesis, mitochondria are reprogrammed to drive the differentiation process before finally being eliminated by mitophagy. In erythropoiesis, mitochondrial dynamics (MtDy) are expected to be a key regulatory point that has not been described previously. We described that a specific MtDy pattern occurs in human erythropoiesis from EPO-induced human CD34+ cells, characterized predominantly by mitochondrial fusion at early stages followed by fission at late stages. The fusion protein MFN1 and the fission protein FIS1 are shown to play a key role in the progression of erythropoiesis. Fragmentation of the mitochondrial web by the overexpression of FIS1 (gain of fission) resulted in both the inhibition of hemoglobin biosynthesis and the arrest of erythroid differentiation, keeping cells in immature differentiation stages. These cells showed specific mitochondrial features as compared with control cells, such as an increase in round and large mitochondrial morphology, low mitochondrial membrane potential, a drop in the expression of the respiratory complexes II and IV and increased ROS. Interestingly, treatment with the mitochondrial permeability transition pore (mPTP) inhibitor, cyclosporin A, rescued mitochondrial morphology, hemoglobin biosynthesis and erythropoiesis. Studies presented in this work reveal MtDy as a hot spot in the control of erythroid differentiation, which might signal downstream for metabolic reprogramming through regulation of the mPTP. © Copyright © 2020 Gonzalez-Ibanez, Ruiz, Jensen, Echeverria, Romero, Stiles, Shirihai and Elorza.https://www.frontiersin.org/articles/10.3389/fcell.2020.592035/ful

    Proxy-reported quality of life in adolescents and adults with dyskinetic cerebral palsy is associated with executive functions and cortical thickness

    Full text link
    Purpose: Quality of life (QOL) is a key outcome for people with cerebral palsy (CP), and executive functioning is an important predictor of QOL in other health-related conditions. Little is known about this association in CP or about its neural substrate. We aim to analyze the influence of executive functioning (including cognitive flexibility) as well as that of other psychological, motor, communication and socioeconomic variables on QOL and to identify neuroanatomical areas related to QOL in adolescents and adults with CP. Methods: Fifty subjects diagnosed with dyskinetic CP (mean age 25.96 years) were recruited. Their caregivers completed the primary caregiver proxy report version of the CP QOL-Teen questionnaire. Motor status, communication, IQ, four executive function domains, anxiety/depression and socioeconomic status were evaluated. Correlations and multiple linear regression models were used to relate CP QOL domains and total score to these variables. Thirty-six participants underwent an MRI assessment. Correlations were examined between cortical thickness and CP QOL total score and between cortical thickness and variables that might predict the CP QOL total score. Results: Executive functions predict scores in four domains of CP QOL (General well-being and participation, Communication and physical health, Family health and Feelings about functioning) in the regression model. Among the cognitive domains that comprise executive function, only cognitive flexibility measured in terms of performance on the Wisconsin card sorting test (WCST) predicts the CP QOL total score. Monthly income, fine motor functioning and communication ability predict scores on the domains Access to services and Family Health, Feelings about functioning and School well being, respectively. The clusters resulting from the correlation between cortical thickness and both CP QOL total score and WCST performance overlapped in the posterior cingulate and precuneus cortices. Conclusions: Cognitive flexibility predicts proxy report CP QOL-Teen total score in dyskinetic CP. This relationship has its anatomical correlate in the posterior cingulate and precuneus cortices

    Cutting Edge Technologies in Postharvest Research: Journey to the Centre of the Fruit

    Get PDF
    Food microstructure is at the base of many food quality roperties. The EU project InsideFood focuses on the pplication of high technological techniques to inspect internal quality of fruit. Tomographic techniques such as magnetic resonance imaging, X-ray computed tomography, optical coherence tomography and confocal microscopy can be used to obtain information about the 3-D microstructure of the fruit which is believed to affect quality attributes such as texture. Optical techniques such as spatially or time resolved reflectance spectroscopy may also be used to obtain information about fruit microstructure. This microstructural information can be incorporated in multiscale simulation models to predict the cellular gas concentrations in fruit. Such models aid towards a better understanding of, for instance, controlled atmosphere storage of apple and postharvest behaviour of fruits and vegetables in general
    corecore