APPL endosomes are not obligatory endocytic intermediates but act as stable cargo-sorting compartments

Endocytosis allows cargo to enter a series of specialized endosomal compartments, beginning with early endosomes harboring Rab5 and its effector EEA1. There are, however, additional structures labeled by the Rab5 effector APPL1 whose role in endocytic transport remains unclear. It has been proposed that APPL1 vesicles are transport intermediates that convert into EEA1 endosomes. Here, we tested this model by analyzing the ultrastructural morphology, kinetics of cargo transport, and stability of the APPL1 compartment over time. We found that APPL1 resides on a tubulo-vesicular compartment that is capable of sorting cargo for recycling or degradation and that displays long lifetimes, all features typical of early endosomes. Fitting mathematical models to experimental data rules out maturation of APPL1 vesicles into EEA1 endosomes as a primary mechanism for cargo transport. Our data suggest instead that APPL1 endosomes represent a distinct population of Rab5-positive sorting endosomes, thus providing important insights into the compartmental organization of the early endocytic pathway.

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Drying Kinetics of Noni Seeds

Journal of Agricultural Science ◽

10.5539/jas.v11n5p250 ◽

2019 ◽

Vol 11 (5) ◽

pp. 250 ◽

Cited By ~ 2

Author(s):

Wellytton Darci Quequeto ◽

Osvaldo Resende ◽

Patrícia Cardoso Silva ◽

Fábio Adriano Santos e Silva ◽

Lígia Campos de Moura Silva

Keyword(s):

Experimental Data ◽

Activation Energy ◽

Diffusion Coefficient ◽

Moisture Content ◽

Mathematical Models ◽

Effective Diffusion Coefficient ◽

Effective Diffusion ◽

Information Criterion ◽

Drying Kinetics ◽

Kinetics Of

Noni seeds have been used for years as an important medicinal source, with wide use in the pharmaceutical and food industry. Drying is a fundamental process in the post-harvest stages, where it enables the safe storage of the product. Therefore, the present study aimed to fit different mathematical models to experimental data of drying kinetics of noni seeds, determine the effective diffusion coefficient and obtain the activation energy for the process during drying under different conditions of air temperature. The experiment used noni seeds with initial moisture content of 0.46 (decimal, d.b.) and dehydrated up to equilibrium moisture content. Drying was conducted under different controlled conditions of temperature, 40; 50; 60; 70 and 80 ºC and relative humidity, 24.4; 16.0; 9.9; 5.7 and 3.3%, respectively. Eleven mathematical models were fitted to the experimental data. The parameters to evaluate the fitting of the mathematical models were mean relative error (P), mean estimated error (SE), coefficient of determination (R2), Chi-square test (c2), Akaike Information Criterion (AIC) and Schwarz’s Bayesian Information Criterion (BIC). Considering the fitting criteria, the model Two Terms was selected to describe the drying kinetics of noni seeds. Effective diffusion coefficient ranged from 8.70 to 23.71 × 10-10 m2 s-1 and its relationship with drying temperature can be described by the Arrhenius equation. The activation energy for noni seeds drying was 24.20 kJ mol-1 for the studied temperature range.

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Microwave Drying of Tilapia Fillets: Kinetics and Modeling

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.396-398.1306 ◽

2011 ◽

Vol 396-398 ◽

pp. 1306-1312 ◽

Cited By ~ 1

Author(s):

Bao Yan Zhang ◽

Yin Zhe Jin ◽

Yu Dong Cheng

Keyword(s):

Experimental Data ◽

Temperature Distribution ◽

Mathematical Models ◽

Output Power ◽

Moisture Diffusivity ◽

Microwave Drying ◽

Effective Moisture Diffusivity ◽

Effective Moisture ◽

Tilapia Fillets ◽

Kinetics Of

To study the effect of microwave output power on the drying kinetics of tilapia fillets, the drying experiments were carried out at 150W, 250W, 500W, 700W and 900W, respectively. And ten mathematical models were involved to fit experimental data. It was found that Midilli et al model gave a best fitness for this conditions applied. Besides, effective moisture diffusivity increased progressively from 1.6248×10-9(m2/s) to 10.0735×10-9(m2/s) as the power increased from 150W to 900W. In addition, to obtain more homogeneous samples, temperature distribution of tilapia fillets was analyzed when they were put in different layout forms.

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Kinetics of Drying and Physical-Chemical Quality of Peach cv. Hubimel

Journal of Agricultural Science ◽

10.5539/jas.v11n16p223 ◽

2019 ◽

Vol 11 (16) ◽

pp. 223

Author(s):

Newton C. Santos ◽

Sâmela L. Barros ◽

Shênia S. Monteiro ◽

Semirames do N. Silva ◽

Victor H. de A. Ribeiro ◽

...

Keyword(s):

Experimental Data ◽

Mathematical Models ◽

Effect Of Temperature ◽

Initial Time ◽

High Water Content ◽

Chemical Quality ◽

Drying Time ◽

Physical Chemical ◽

Kinetics Of

The objective of this study was to perform the kinetics of peach drying and to adjust the experimental data obtained to empirical and diffusive mathematical models to evaluate the effect of temperature on the physical-chemical quality of the final product. The drying experiments were performed in an air circulation dryer with a velocity of 1.5 m s-1, the drying kinetics were performed at temperatures of 60, 70 and 80 °C. Among the mathematical models applied, the Page model was the one that best fit the experimental data, because it presents greater efficiency in the description of the drying process. The decrease in the drying rate from the initial time to the end of the process was observed, increasing the temperature of the air caused a reduction in the drying time. It was verified through the analytical solution of the diffusion equation with infinite wall geometry that the increase of the drying temperature caused the increase of the diffusivity and convective coefficient of heat transfer. Through the Biot number, it can be stated that the first-type boundary condition would also describe the process satisfactorily. The fresh peach slices present high water content and water activity and the drying effect caused significant differences in all physical-chemical parameters analyzed.

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The Mycobacterium tuberculosis phagosome interacts with early endosomes and is accessible to exogenously administered transferrin.

Journal of Experimental Medicine ◽

10.1084/jem.184.4.1349 ◽

1996 ◽

Vol 184 (4) ◽

pp. 1349-1355 ◽

Cited By ~ 228

Author(s):

D L Clemens ◽

M A Horwitz

Keyword(s):

Mycobacterium Tuberculosis ◽

Culture Medium ◽

Direct Evidence ◽

Human Monocyte ◽

Endocytic Pathway ◽

Time Dependent ◽

Late Endosomes ◽

Latex Beads ◽

Early Endosomes ◽

Kinetics Of

Previous studies have demonstrated that the Mycobacterium tuberculosis phagosome in human monocyte-derived macrophages acquires markers of early and late endosomes, but direct evidence of interaction of the M. tuberculosis phagosome with the endosomal compartment has been lacking. Using the cryosection immunogold technique, we have found that the M. tuberculosis phagosome acquires exogenously added transferrin in a time-dependent fashion. Near-maximal acquisition of transferrin occurs within 15 min, kinetics of acquisition consistent with interaction of the M. tuberculosis phagosome with early endosomes. Transferrin is chased out of the M. tuberculosis phagosome by incubation of the infected macrophages in culture medium lacking human transferrin. Phagosomes containing latex beads or heat-killed M. tuberculosis, on the other hand, do not acquire staining for transferrin. These and other findings demonstrate that M. tuberculosis arrests the maturation of its phagosome at a stage at which the phagosome interacts with early and late endosomes, but not with lysosomes. The transferrin endocytic pathway potentially provides a novel route for targeting antimicrobials to the M. tuberculosis phagosome.

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SECAGEM DA BATATA YACON (SMALLANTHUS SONCHIFOLIUS) UTILIZANDO MICROONDAS

e-xacta ◽

10.18674/exacta.v6i2.768 ◽

2013 ◽

Vol 6 (2) ◽

pp. 147

Author(s):

Sérgio Luís Marcussi Vitor da Silva ◽

Luciana Maria Seara ◽

Andrea Teixeira Charbel

Keyword(s):

Experimental Data ◽

Nutritional Value ◽

Microwave Frequency ◽

Practical Method ◽

Microwave Oven ◽

Operating Parameters ◽

Drying Process ◽

Smallanthus Sonchifolius ◽

Kinetics Of ◽

Over Time

O presente trabalho tem como objetivo principal estudar os parâmetros de operação do processo de secagem do tubérculo de Yacon usando energia eletromagnética na freqüência de microondas. A desidratação é um meio de preservar e conservar os alimentos de forma segura e ainda manter estavelmente suas propriedades. Os tubérculos de Yacon apresentam a característica de armazenar em suas raízes, em vez de amido, frutooligossacarídeos (FOS) como fonte de reserva de energia. Os frutooligossacarídeos são fibras e têm propriedades pré-bióticas, fator enriquecedor do valor nutricional dos alimentos. As variáveis estudadas foram a exaustão do ar da câmera do forno de microondas, a potência aplicada à carga de batatas (750 W e 350 W) e a temperatura do ar de secagem (30 ºC e 60 ºC). Pôde-se concluir que a variação da potência resultou em diferenças significativas na cinética do processo que, em aproximadamente 35 min, reduziu a umidade da batata Yacon de 91,8 % até 5 %.. Os dados experimentais, referentes à variação da umidade ao longo do tempo, foram ajustados a uma equação Gaussiana, que se mostrou adequada para representar o processo. A tecnologia de secagem por meio de microondas constitui um método prático para a introdução dos frutooligossacarídeos na dieta da população.AbstractThe present work has as main objective to study the operating parameters of the drying process Yacon tuber using electromagnetic energy in the microwave frequency. Dehydration is a means of preserving and storing food safely and stably while maintaining their properties. The Yacon tubers have the feature store in its roots, instead of starch, fructooligosaccharides (FOS) as a source of backup power. Fructooligosaccharides are fibers and have prebiotic properties, a factor enriching the nutritional value of foods. The variables studied were the exhaust air from the camera of the microwave oven, the power applied to the load of potatoes (750 W and 350 W) and drying air temperature (30 °C and 60 °C). It was concluded that the change in power resulted in significant differences in the kinetics of the process in approximately 35 min, reduced moisture Yacon potato 91.8% to 5%. The experimental data relating to humidity variation over time were adjusted to a gaussian equation which was adequate to represent the process. The technology of drying by microwaves is a practical method for the introduction of fructooligosaccharides in the brazilian diet.

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Maturation of early endosomes and vesicular traffic to lysosomes in relation to membrane recycling

Journal of Cell Science ◽

10.1242/jcs.108.4.1791 ◽

1995 ◽

Vol 108 (4) ◽

pp. 1791-1803 ◽

Cited By ~ 4

Author(s):

L. Thilo ◽

E. Stroud ◽

T. Haylett

Keyword(s):

Fluid Phase ◽

Endocytic Pathway ◽

Second Phase ◽

Membrane Recycling ◽

Order Process ◽

Vesicular Traffic ◽

First Order ◽

Early Endosomes ◽

Kinetics Of ◽

Late Stages

The controversy whether endocytic processing occurs by organellar maturation or by vesicular traffic has not been resolved. It is also not clear whether maturation continues to the stage of lysosomes, to what extent it involves a decrease in organellar fusogenicity, and how it relates to membrane recycling. Maturation and vesicular traffic imply distinct kinetics for the intermingling of endocytic markers after sequential endocytic uptake. We have studied the kinetics of intermingling of fluid-phase markers (fluorescein-labelled dextran and horseradish peroxidase) and cell surface-derived membrane (labelled by galactosylation) in organelles at early and late stages of the endocytic pathway in macrophage-like P388D1 cells. Intermingling declined by sigmoid kinetics, indicating that endosomes matured within about 3 minutes to become non-fusogenic towards early endosomes. During maturation about 60% of internalized membrane was recycled with T1/2 approximately 2 minutes. Whereas matured endosomes were non-fusogenic towards early endosomes and towards each other, a second phase of intermingling was observed upon delivery to lysosomes. This intermingling occurred by a first-order process (T1/2 approximately 4 minutes), concurrent with recycling of the remaining 40% of internalized membrane marker. These kinetic observations suggest a model for endocytic processing which reconciles maturation of early endosomes with the known function of carrier vesicles: Endocytic carrier vesicles do not bud off from permanent early endosomes as proposed for vesicular traffic, but are derived, together with recycling vesicles, from the maturation of early endosomes which are consumed by this process; these carrier vesicles subsequently mediate delivery to lysosomes by vesicular traffic during which the remaining surface-derived membrane is recycled.

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Cinética de secagem de vagens de algaroba (Prosopis juliflora SW)

Revista Verde de Agroecologia e Desenvolvimento Sustentável ◽

10.18378/rvads.v10i5.3338 ◽

2015 ◽

Vol 10 (5) ◽

pp. 115

Author(s):

A. P. S. Nascimento ◽

A. K. S. Lima ◽

C. F. Cavalcanti ◽

R. P. Gusmão

Keyword(s):

Experimental Data ◽

Thin Layer ◽

Mathematical Models ◽

Prosopis Juliflora ◽

Drying Kinetics ◽

Coefficient Of Determination ◽

Fine Mesh ◽

Rate Period ◽

Air Dryer ◽

Kinetics Of

O objetivo deste trabalho foi estudar a cinética de secagem de vagens de algaroba em secador convectivo, nas temperaturas de 60, 70 e 80 °C. A secagem foi conduzida em camada fina, em um secador com circulação de ar, onde as vagens foram colocados em um recipiente de alumínio, medindo 20 mm de comprimento e 10 mm de largura, com capacidade de aproximadamente 10 g. Para representar o comportamento cinético da secagem foram utilizados os modelos matemáticos de Page, Henderson & Pabis e Exponencial de Dois Termos. A partir dos resultados obtidos foi possível concluir que a secagem das vagens de algaroba ocorreu durante o período de taxa decrescente e é influenciada pela ação da temperatura, ou seja, ao aumentar a temperatura de secagem tem-se uma diminuição no tempo de estabilização, podendo este processo ser representado pelos três modelos matemáticos estudados, sendo o modelo Exponencial de Dois Termos o que melhor se ajustou aos dados experimentais apresentando coeficiente de determinação superior a 99,8% e desvios quadráticos médios menores que 0,05.Drying kinetics of pods of algaroba (Prosopis juliflora SW)Abstract: The objective of this work was to study the drying kinetics of algaroba pods in convective dryer at temperatures of 60, 70 and 80 °C. The drying was carried out in thin layer in a circulating air dryer where the beans were placed in a fine mesh metal container measuring 20 mm long and 10 mm wide, with a capacity of approximately 10 g. To represent the kinetics of drying the mathematical models of Page, Henderson and Pabis and Exponential of Two Terms were tested. Based on the results obtained it was concluded that the drying of algaroba pods occurs during falling rate period and is influenced by the action of temperature, in other words, by increasing the drying temperature has been a decrease in settling time, this process can be represented by the three mathematical models considered, being the Exponential of Two Terms model which best fits the experimental data showing higher coefficient of determination 98% and lower DQM.

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A fuzzy neural network approach for modeling the growth kinetics of FeB and Fe2B layers during the boronizing process

Matériaux & Techniques ◽

10.1051/mattech/2019002 ◽

2018 ◽

Vol 106 (6) ◽

pp. 603 ◽

Cited By ~ 2

Author(s):

Bendaoud Mebarek ◽

Mourad Keddam

Keyword(s):

Neural Network ◽

Experimental Data ◽

Fuzzy Neural Network ◽

Treatment Time ◽

Calculation Model ◽

Average Error ◽

Network Approach ◽

Neural Network Approach ◽

Fuzzy Neural ◽

Kinetics Of

In this paper, we develop a boronizing process simulation model based on fuzzy neural network (FNN) approach for estimating the thickness of the FeB and Fe2B layers. The model represents a synthesis of two artificial intelligence techniques; the fuzzy logic and the neural network. Characteristics of the fuzzy neural network approach for the modelling of boronizing process are presented in this study. In order to validate the results of our calculation model, we have used the learning base of experimental data of the powder-pack boronizing of Fe-15Cr alloy in the temperature range from 800 to 1050 °C and for a treatment time ranging from 0.5 to 12 h. The obtained results show that it is possible to estimate the influence of different process parameters. Comparing the results obtained by the artificial neural network to experimental data, the average error generated from the fuzzy neural network was 3% for the FeB layer and 3.5% for the Fe2B layer. The results obtained from the fuzzy neural network approach are in agreement with the experimental data. Finally, the utilization of fuzzy neural network approach is well adapted for the boronizing kinetics of Fe-15Cr alloy.

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