Journal articles on the topic 'Digestion Simulation methods'
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1
Witaszek, Kamil, Marcin Herkowiak, Agnieszka A. Pilarska, and Wojciech Czekała. "Methods of Handling the Cup Plant (Silphium perfoliatum L.) for Energy Production." Energies 15, no. 5 (March 4, 2022): 1897. http://dx.doi.org/10.3390/en15051897.
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The aim of the study was to determine the possibilities of using cup plants (Silphium perfoliatum L.) to generate energy. The energy balances of the combustion and anaerobic digestion were compared. The research showed that cup plants could be used as a raw material for solid fuel and for anaerobic digestion. An energy balance simulation showed that electricity could be generated through the anaerobic digestion of cup plants. The following amounts could be generated in the anaerobic digestion process: 1069 kWhe from 1 Mg of the raw material fragmented with an impact mill, 738.8 kWhe from 1 Mg of the raw material extruded at a temperature of 150 °C, and as much as 850.1 kWhe from 1 Mg of the raw material extruded at 175 °C. The energy balance of the combustion of biofuel in the form of cup plant pellets showed that 858.28 kWht could be generated from 1 Mg of the raw material. The combustion of solid biofuel generated a relatively low amount of heat in comparison with the expected amount of heat from a biogas-powered cogeneration system due to the high energy consumption of the processes of drying and agglomeration of the raw material for the production of pellets.
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Sirovec, Sara, Ana Jurinjak Tušek, Maja Benković, Davor Valinger, Tea Sokač Cvetnić, Jasenka Gajdoš Kljusurić, and Tamara Jurina. "Emulsification of Rosemary and Oregano Aqueous Extracts and Their In Vitro Bioavailability." Plants 11, no. 23 (December 4, 2022): 3372. http://dx.doi.org/10.3390/plants11233372.
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Due to their richness in phenolic compounds, Mediterranean plants such as rosemary and oregano are increasingly recommended for consumption for their numerous health benefits. The pH shift and the presence of digestive enzymes significantly reduce the bioavailability of these biochemicals as they pass through the gastrointestinal tract. To prevent this degradation of phenolic compounds, methods such as emulsification of plant aqueous extracts are used. The aim of this study was to investigate the effects of emulsification conditions on the chemical properties (total polyphenolic content and antioxidant activity) of emulsified rosemary and oregano extracts. Response surface methodology was applied to optimize sunflower oil concentration, rotational speed, and emulsifier concentration (commercial pea protein). The emulsions prepared under optimal conditions were then used in bioavailability studies (in vitro digestion). The antioxidant activity of the emulsified rosemary/oregano extracts, measured by the DPPH method, remained largely stable when simulating in vitro digestion. Analysis of antioxidant activity after in vitro simulation of the gastrointestinal system revealed a higher degree of maintenance (up to 76%) for emulsified plant extracts compared to aqueous plant extracts. This article contributes to our understanding of how plant extracts are prepared to preserve their biological activity and their application in the food industry.
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Liu, Hui, Qian Li, and Chunbao Li. "Changes in the Structure and Digestibility of Myoglobin Treated With Sodium Chloride." Current Developments in Nutrition 5, Supplement_2 (June 2021): 661. http://dx.doi.org/10.1093/cdn/nzab045_043.
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Abstract Objectives Changes in the structure of myoglobin affect its digestibility and myoglobin can't be completely broken down of pepsin. The exact mechanism of this breakdown is not clear. It can be inferred that myoglobin is broken down into polypeptides whose structures do not fully conform to the spatial characteristics of digestive enzymes. Myoglobin dissolution in different salt concentrations and changes in secondary structure were examined by spectroscopic examination. The molecular dynamics simulation was used to study the stability of these structural changes and their combination with digestive enzymes. Finally, since the products of digestion are determined by the catalytic centers of digestive enzymes, the substrate channel is extended to study the relationship between digestive enzymes and substrates. Methods In this study, different concentrations of sodium chloride were added for a certain period of time in advance to detect changes in the secondary structure of myoglobin, leading to changes in digestibility. Myoglobin and digestive enzymes were docked for molecular dynamics simulations to analyze the energy and structural changes in the interactions between substrates and proteins. Results Salt-treated protein can affect the secondary structure changes of protein. High concentration of salt-treated protein will lead to protein aggregation and denaturation, affecting digestibility. Low concentration of salt-treated protein may lead to exposure of sleeping areas, reducing digestibility. In terms of structure, salt ions lead to changes in the bonding of amino acids in the protein and affect the substrate's entry into the enzyme activity center. Conclusions Treatment of myoglobin with different salt concentrations did not change its tertiary structure but low salt concentrations lowered its digestibility, probably due to salt ions altering a number of key amino acid bonds, making the structure more stable and less susceptible to digest. Some low molecular weight peptides remain after pepsin digestion. This may be due to the distance between the key amino acids in the active catalytic center of pepsin being insufficient to form stable conformations with small peptides. Funding Sources This work was supported by the grants from NSFC (32072211).
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Condrachi, Larisa, Ramón Vilanova, Montse Meneses, and Marian Barbu. "Anaerobic Digestion Process Control Using a Data-Driven Internal Model Control Method." Energies 14, no. 20 (October 16, 2021): 6746. http://dx.doi.org/10.3390/en14206746.
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Anaerobic digestion processes offer the possibility for wastewater treatment while obtaining a benefit through the obtained biogas. This paper aims to continue the effort to adopt data-driven control methods in the case of anaerobic digestion processes. The paper proposes a data-based Internal Model Control approach applied to an anaerobic digestion process. The paper deals extensively with the issue of choosing the reference model and proposing an engineering approach to this issue. The paper also addresses the issue of verifying robust stability, a very important aspect considering the uncertainties that characterize bioprocesses in general. The approach proposed in the paper is validated through a numerical simulation using the Anaerobic Digestion Model No. 1. During the validation of the proposed control solution, the main operating conditions were analyzed, such as the setpoint tracking performance, the rejection of disturbance generated by variations in the influent concentration, and the effect of the measurement noise on the controlled variable.
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Kitessa, S., G. G. Irish, and P. C. Flinn. "Comparison of methods used to predict the in vivo digestibility of feeds in ruminants." Australian Journal of Agricultural Research 50, no. 5 (1999): 825. http://dx.doi.org/10.1071/ar98169.
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Digestibility is a very useful index of the energy content of ruminant feeds, but cheaper and quicker laboratory methods are required as an alternative to the ultimate measure of in vivo digestibility using animals. These methods involve either prediction of digestibility from chemical composition or in vitro and in situ simulation of the digestion process. This review presents a range of chemical and in vitro techniques for predicting digestibility, together with an assessment of their advantages and limitations, particularly the degree to which they account for the sources of variation in in vivo digestibility in ruminants. In situ digestion of feed samples in the actual rumen environment is probably the most accurate of the non in vivo procedures, but is not suitable for routine application. Thein vitro gas production technique offers no advantages in prediction of total tract digestibility, but is useful for screening cereal grains for rate of starch hydrolysis in the rumen. The preferred procedure for routine laboratory prediction of digestibility is the pepsin-cellulase technique, provided amylase is included or high temperature digestion is used for samples high in starch content. Prediction of digestibility from chemical composition is not recommended. The optical technique of near infrared reflectance spectroscopy can be calibrated against any of the methods outlined in this review, and is unsurpassed in terms of speed and repeatability. Direct NIR prediction of in vivo digestibility is also possible, but is limited by the lack of adequate numbers of feed samples with known in vivo values. Future work should be aimed at filling this gap and also improving the accuracy of laboratory methods for predicting the digestibility of low quality feeds.
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Sainz, Roberto D., R. Lee Baldwin, and Ricardo F. Venazza. "Modelos de crecimiento, digestión y lactancia en bovinos." Corpoica Ciencia y Tecnología Agropecuaria 3, no. 2 (July 31, 2001): 65. http://dx.doi.org/10.21930/rcta.vol3_num2_art:188.
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<p>Los métodos utilizados comunmente para predecir el comportamiento animal como función del manejo de la alimentación, se encuentran en un proceso de cambio. Los sistemas actualmente utilizados para estimar los requerimientos animales, basados en ecuaciones algebráicas estáticas han empezado a ser sustituidos por modelos dinámicos de simulación capaces de caracterizar la respuesta animal para un rango de condiciones mucho mayor a aquel usado en los sistemas tradicionales. En este artículo se exponen los modelos para describir los procesos de crecimiento, digestión y lactancia bovinos. </p><p><strong><br /></strong></p><p><strong>Models for growth digestion and lactation in bovine</strong></p><p>The methods commonly used to predict animal behavior as a function of feeding management, are in a process of change. The systems currently used for estimating the animal requirements based on static algebraic equations have begun to be replaced by dynamic simulation models capable of characterizing animal response for a much wider range of conditions to that used in traditional systems. In this article models are presented to describe the processes of growth, digestion and feeding cattle.</p>
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Tormási, Judit, and László Abrankó. "Assessment of Fatty Acid-Specific Lipolysis by In Vitro Digestion and GC-FID." Nutrients 13, no. 11 (October 29, 2021): 3889. http://dx.doi.org/10.3390/nu13113889.
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The nutritional relevance of food compositional data could be improved by taking the bioaccessibility of these constituents into account. A lack of routine methods to assess the bioaccessibility of fatty acids (FAs) in food is one of the limiting factors of doing so. An analytical protocol is proposed for routine assessment of the extent of lipolysis via in vitro digestion simulation methods in food products. The established method provides specific information on each FA individually. Steps of the protocol including the Bligh and Dyer chloroform/methanol/water extraction of esterified and free FAs from in vitro digesta, methyl ester derivatization, and GC-FID analysis were specifically tailored to help routine work and were harmonized with the Infogest in vitro digestion simulation protocol (both v1.0 and v2.0). The method was applied to assess the degree of FA-specific lipolysis in a baked fish (carp) meal and the results showed that the FA composition of the original food significantly differed from that of the distribution of FFAs in the digesta. The use of gastric lipase (in Infogest v2.0 protocol) increased total FA release by 9.5% and its specific impact on palmitic acid was the most prominent.
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İnan, Yiğit, Selin Akyüz, Inci Kurt-Celep, Engin Celep, and Erdem Yesilada. "Influence of In Vitro Human Digestion Simulation on the Phenolics Contents and Biological Activities of the Aqueous Extracts from Turkish Cistus Species." Molecules 26, no. 17 (September 1, 2021): 5322. http://dx.doi.org/10.3390/molecules26175322.
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Oxidative stress is one of the significant precursors of various metabolic diseases such as diabetes, Parkinson’s disease, cardiovascular diseases, cancer, etc. Various scientific reports have indicated that secondary plant metabolites play an important role in preventing oxidative stress and its harmful effects. In this respect, this study was planned to investigate the phenolic profile and antioxidant and antidiabetic potentials of the aqueous extracts from Turkish Cistus species by employing in vitro methods. In vitro digestion simulation procedure was applied to all extracts to estimate the bioavailability of their phenolic contents. Total phenolic, flavonoid, phenolic acid and proanthocyanidin contents were determined for all phases of digestion. In addition, changes in the quantity of the assigned marker flavonoids (tiliroside, hyperoside and quercitrin) were monitored by High-Performance Thin Layer Chromatography (HPTLC) analysis. The antioxidant activity potentials of the extracts were studied by various methods to reveal their detailed activity profiles. On the other hand, in vitro α-amylase and α-glucosidase enzymes and advanced-glycation end product (AGE) inhibitory activities of the extracts were determined to evaluate the antidiabetic potentials of extracts. The results showed that aqueous extracts obtained from the aerial parts of Turkish Cistus species have rich phenolic contents and potential antioxidant and antidiabetic activities; however, their bioactivity profiles and marker flavonoid concentrations might significantly be affected by human digestion. The results exhibited that total phenolic contents, antioxidant activities and diabetes-related enzyme inhibitions of the bioavailable samples were lower than non-digested samples in all extracts.
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González-Arias, C. A., S. Marín, V. Sanchis, and A. J. Ramos. "Mycotoxin bioaccessibility/absorption assessment using in vitro digestion models: a review." World Mycotoxin Journal 6, no. 2 (May 1, 2013): 167–84. http://dx.doi.org/10.3920/wmj2012.1521.
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In the evaluation of the oral bioavailability of a mycotoxin, the first step is the determination of its bioaccessibility, i.e. the percentage of mycotoxin released from the food matrix during digestion in the gastrointestinal (GI) tract that could be absorbed through the intestinal epithelium. Different in vitro digestion models have been recently used for determination of bioaccessibility, thereby avoiding the use of more complex cell culture techniques or the use of animals in expensive in vivo experiments. In vitro methods offer an appealing alternative to human and animal studies. They usually are rapid, simple and reasonably low in cost, and can be used to perform simplified experiments under uniform and well-controlled conditions, providing insights not achievable in whole animal studies. The available in vitro methods for GI simulation differ in the design of the system, the composition of the physiological juices assayed, as well as in the use or not of intestinal microbiota. There are models that only simulate the upper part of the GI tract (mouth-stomach-small intestine), whereas other methods include the large intestine, so that the model chosen could have some influence on the bioaccessibility data obtained. Bioaccessibility depends on the food matrix, as well as on the contamination level and the way the food/feed is contaminated (spiked or naturally). This review focuses on the currently available data regarding in vitro digestion models for the study of the bioaccessibility or absorption of mycotoxins, detailing the characteristics of each digestion step and the importance of the physiological juices employed during digestion. The effect that different factors play on mycotoxin release from the food matrix in the GI tract is also considered, and existing data on bioaccessibility of the main mycotoxins are given.
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Gaida, D., C. Wolf, C. Meyer, A. Stuhlsatz, J. Lippel, T. Bäck, M. Bongards, and S. McLoone. "State estimation for anaerobic digesters using the ADM1." Water Science and Technology 66, no. 5 (September 1, 2012): 1088–95. http://dx.doi.org/10.2166/wst.2012.286.
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The optimization of full-scale biogas plant operation is of great importance to make biomass a competitive source of renewable energy. The implementation of innovative control and optimization algorithms, such as Nonlinear Model Predictive Control, requires an online estimation of operating states of biogas plants. This state estimation allows for optimal control and operating decisions according to the actual state of a plant. In this paper such a state estimator is developed using a calibrated simulation model of a full-scale biogas plant, which is based on the Anaerobic Digestion Model No.1. The use of advanced pattern recognition methods shows that model states can be predicted from basic online measurements such as biogas production, CH4 and CO2 content in the biogas, pH value and substrate feed volume of known substrates. The machine learning methods used are trained and evaluated using synthetic data created with the biogas plant model simulating over a wide range of possible plant operating regions. Results show that the operating state vector of the modelled anaerobic digestion process can be predicted with an overall accuracy of about 90%. This facilitates the application of state-based optimization and control algorithms on full-scale biogas plants and therefore fosters the production of eco-friendly energy from biomass.
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Tánori-Encinas, Daniel, Abraham Wall-Medrano, José Luis Cárdenas-López, Ana Irene Ledesma-Osuna, and Maribel Robles-Sánchez. "Cápsulas de polvo de arándano como propuesta nutracéutica para mejorar la bioaccesibilidad de compuestos fenólicos." Archivos Latinoamericanos de Nutrición 72, no. 1 (April 30, 2022): 11–22. http://dx.doi.org/10.37527/2022.72.1.002.
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Blueberry (Vaccinium corymbosum L.) has a high content of phenolic compounds which have been studied mainly for their antioxidant, antiobesogenic, anti-inflammatory activity, among others. Objetive. The objective of the present study was to evaluate the effect of in vitro gastrointestinal digestion on the bioaccessibility of phenolic compounds and antioxidant activity of a nutraceutical formulation of blueberry (capsule), compared to fresh and powder blueberry. Materials and methods. Methanolic extracts of fresh and lyophilized blueberry were obtained and determined its total phenols, flavonoids, anthocyanins content, as well as antioxidant activity. A gastrointestinal digestion simulation test also was carried out to assess the bioaccessibility of the phenolic compounds found in samples. Results. The results showed that gastric digestion of powder and capsule blueberry promoted greater bioaccessibility of phenols (42% and 40%), flavonoids (52% and 33%) and anthocyanins (45% and 40%), compared to fresh blueberry digests. After intestinal digestion, the bioaccessibility of phenols (63%) and flavonoids (67%) was higher in the blueberry capsule compared to its powdered blueberry counterpart. The intestinal digestion conditions negatively affected the bioaccessibility of anthocyanins regardless of the type of sample evaluated. Conclusion. Gastric digestion conditions promote greater stability of phenolic compounds in powdered and capsule blueberries, which could be relevant for the maintenance of an antioxidant environment at this level. The intestinal digestion conditions particularly affected the phenolic compounds of fresh and lyophilized blueberry, but not the capsule, which may suggest that encapsulation protected the phenols present from alkaline conditions. Further studies on in vitro absorption of the remaining components in the intestine and their possible effects on oxidative stress biomarkers in in vivo models are suggested.
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Mathur, Rajshree, and Meena Kumari Sharma. "Modeling and optimization of the anaerobic digestion system for domestic waste water treatment with the development of monitoring techniques." IOP Conference Series: Earth and Environmental Science 1084, no. 1 (October 1, 2022): 012046. http://dx.doi.org/10.1088/1755-1315/1084/1/012046.
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Abstract Water scarcity and wastewater management are two most serious environmental problems faced by developing countries like India. Recycling and reuse of the treated wastewater for non-potable purpose may significantly reduce the stress on fresh water requirement. Anaerobic digestion methods are used to treat wastewater discharge from various fields. Software tools provide an opportunity for engineers to create models which represent activities, resources, and the environment in powerful, affordable and user-friendly way. Modeling and simulation results serve as an important guideline in the optimization and process control for plant operators and other specialists in the field of engineering. Model-based development of software using tools such as Math Works Simulink has become common in the engineering. The Anaerobic Digestion Model (ADM1) from the International Water Association might be used for modeling and optimization of digestion operations. This research reveals the study of domestic wastewater treatment using ADM1. The process equations are solved using the input data, and output is generated. The results show that the proposed method is capable of predicting process parameters of excellent stream with high degree of accuracy (R2=0.945).
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Kleerebezem, R., and M. C. M. van Loosdrecht. "Critical analysis of some concepts proposed in ADM1." Water Science and Technology 54, no. 4 (August 1, 2006): 51–57. http://dx.doi.org/10.2166/wst.2006.525.
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The Anaerobic Digestion Model No. 1 (ADM1) has been developed by the expert task group of the IWA to establish a common platform for simulation of a wide variety of anaerobic degradation processes. It enables comparison of different methods and parameter values for description of specific sub-processes, with the methods and default values proposed by the task group. This will hopefully stimulate a more structured discussion on anaerobic digestion modelling compared to the recent past, when many different researchers developed a slightly different model and it remained largely unclear what could, and what could not be compared. In this paper we take the liberty to criticize some aspects of ADM1 and its implementation, as we think they represent concepts that are too easily extrapolated from activated sludge models. The specific subjects discussed here are the COD-based description of the reaction stoichiometry (i), the widely adopted use of a constant value for the solid retention time high-rate anaerobic bioreactors (ii), and the kinetic description of the acetogenic reactions as proposed in ADM1 (iii).
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Garcia-Tenorio, Camilo, Eduardo Mojica-Nava, Mihaela Sbarciog, and Alain Vande Wouwer. "Analysis of the ROA of an anaerobic digestion process via data-driven Koopman operator." Nonlinear Engineering 10, no. 1 (January 1, 2021): 109–31. http://dx.doi.org/10.1515/nleng-2021-0009.
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Abstract Nonlinear biochemical systems such as the anaerobic digestion process experience the problem of the multi-stability phenomena, and thus, the dynamic spectrum of the system has several undesired equilibrium states. As a result, the selection of initial conditions and operating parameters to avoid such states is of importance. In this work, we present a data-driven approach, which relies on the generation of several system trajectories of the anaerobic digestion system and the construction of a data-driven Koopman operator to give a concise criterion for the classification of arbitrary initial conditions in the state space. Unlike other approximation methods, the criterion does not rely on difficult geometrical analysis of the identified boundaries to produce the classification.
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Sutton, P. M., H. Melcer, O. J. Schraa, and A. P. Togna. "Treating municipal wastewater with the goal of resource recovery." Water Science and Technology 63, no. 1 (January 1, 2011): 25–31. http://dx.doi.org/10.2166/wst.2011.004.
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A new municipal wastewater treatment flowsheet was developed with the objectives of energy sustainability, and water and nutrient recovery. Energy is derived by shunting a large fraction of the organic carbon in the wastewater to an anaerobic digestion system. Aerobic and anaerobic membrane bioreactors play a key role in energy recovery. Phosphorus and nitrogen are removed from the wastewater and recovered through physical-chemical processes. Computer modeling and simulation results together with energy balance calculations, imply the new flowsheet will result in a dramatic reduction in energy usage at lower treatment plant capital costs in comparison to conventional methods.
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Zhang, Miao, En Shi, and Yafeng Li. "Modeling interspecific competition of the microbial community during anaerobic digestion based on cellular automata and ADM1." Water Science and Technology 83, no. 9 (March 25, 2021): 2087–99. http://dx.doi.org/10.2166/wst.2021.113.
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Abstract Interspecific competition for substrate and space gives rise to considerable variation in biomass distribution within the microbial community. To study microbial community in depth, we used several research methods as sampling and analytical measurements, and developed a cellular automata (CA) model that would facilitate a description of the microbial growth process based on Anaerobic Digestion Model No. 1 (ADM1) of the International Water Association (IWA). Using the CA model, we aimed to determine whether interspecific competition occurs among acidogens, acetogens and methanogens, and to examine the influence of interspecific competition on the spatial structure of microbial communities. We found that acetogens and methanogens competed for core space, resulting in a multi-layer structure. Butyrate-degrading acetogens increased in number, resulting in inhibition of propionate-degrading acetogens. Hydrogenotrophic methanogens showed stronger competitive advantage than acetotrophic methanogens. The simulation showed that the multi-layer structure of the microbial community was formed by interspecific competition.
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Kazemi, Pezhman, Jean-Philippe Steyer, Christophe Bengoa, Josep Font, and Jaume Giralt. "Robust Data-Driven Soft Sensors for Online Monitoring of Volatile Fatty Acids in Anaerobic Digestion Processes." Processes 8, no. 1 (January 3, 2020): 67. http://dx.doi.org/10.3390/pr8010067.
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The concentration of volatile fatty acids (VFAs) is one of the most important measurements for evaluating the performance of anaerobic digestion (AD) processes. In real-time applications, VFAs can be measured by dedicated sensors, which are still currently expensive and very sensitive to harsh environmental conditions. Moreover, sensors usually have a delay that is undesirable for real-time monitoring. Due to these problems, data-driven soft sensors are very attractive alternatives. This study proposes different data-driven methods for estimating reliable VFA values. We evaluated random forest (RF), artificial neural network (ANN), extreme learning machine (ELM), support vector machine (SVM) and genetic programming (GP) based on synthetic data obtained from the international water association (IWA) Benchmark Simulation Model No. 2 (BSM2). The organic load to the AD in BSM2 was modified to simulate the behavior of an anaerobic co-digestion process. The prediction and generalization performances of the different models were also compared. This comparison showed that the GP soft sensor is more precise than the other soft sensors. In addition, the model robustness was assessed to determine the performance of each model under different process states. It is also shown that, in addition to their robustness, GP soft sensors are easy to implement and provide useful insights into the process by providing explicit equations.
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Morrissey, Karla G., Leah English, Greg Thoma, and Jennie Popp. "Prospective Life Cycle Assessment and Cost Analysis of Novel Electrochemical Struvite Recovery in a U.S. Wastewater Treatment Plant." Sustainability 14, no. 20 (October 21, 2022): 13657. http://dx.doi.org/10.3390/su142013657.
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Nutrient recovery in domestic wastewater treatment has increasingly become an important area of study as the supply of non-renewable phosphorus decreases. Recent bench-scale trials indicate that co-generation of struvite and hydrogen using electrochemical methods may offer an alternative to existing recovery options utilized by municipal wastewater treatment facilities. However, implementation has yet to be explored at plant-scale. In the development of novel nutrient recovery processes, both economic and environmental assessments are necessary to guide research and their design. The aim of this study was to conduct a prospective life cycle assessment and cost analysis of a new electrochemical struvite recovery technology that utilizes a sacrificial magnesium anode to precipitate struvite and generate hydrogen gas. This technology was modeled using process simulation software GPS-X and CapdetWorks assuming its integration in a full-scale existing wastewater treatment plant with and without anaerobic digestion. Struvite recoveries of 18–33% were achieved when anaerobic digestion was included, with a break-even price of $6.03/kg struvite and $15.58/kg of hydrogen required to offset increased costs for recovery. Struvite recovery reduced aquatic eutrophication impacts as well as terrestrial acidification impacts. Tradeoffs between benefits from struvite and burdens from electrode manufacturing were found for several impact categories.
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Alshammari, Norah, Syahrizal Muttakin, Qingsu Liu, Ourania Gouseti, Jaber Alyami, Alison Lovegrove, Guruprasad P. Aithal, Moira Taylor, and Luca Marciani. "The Effect of Adding Gellan Gum to White Rice on the Starch Hydrolysis and Glycemic Index." Current Developments in Nutrition 5, Supplement_2 (June 2021): 571. http://dx.doi.org/10.1093/cdn/nzab044_002.
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Abstract Objectives High consumption of starchy foods has been linked to increased risk of type 2 diabetes. Addition of food hydrocolloids gums to food has previously been shown to reduce the digestibility of food. Gellan gum, a polysacchairde produced by sphingomonas eldea is one of many available food hydrocolloid gums. The aim of the present study was to examine the effect of adding gellan gum to white rice during cooking on the starch digestibility and related in-vitro glycemic index(GI). Methods A static in-vitro digestion model was used based on the protocol from the INFOGEST static in-vitro simulation of gastrointestinal food digestion model (Brodkorb et al, .2019). Four different samples were prepared: (A) Cooked Jasmine rice; (B) Cooked Jasmine rice + 1% low acyl gellan gum, LAGG (KELCOGEL F, CPKelco); (C) Cooked long grain rice and (D) Cooked long grain rice + 1% LAGG. The oral phase was simulated by adding 5 ml of simulated salivary fluid containing human salivary amylase, followed by gastric phase and an intestinal phase. Glucose release was determined by Sugar Reduction Assay(PAHBAH) and compared to a maltose standard curve at consecutive time points for 2 hours. Results The addition of LAGG inhibited starch hydrolysis for both Jasmine and long grain rice. The greatest effect was observed for Jasmine rice. Starch digestion was reduced with the addition of LAGG to Jasmine rice by 27% and with the addition to long grain rice by 21% at 120 minutes. The GI was calculated using the area under curve and white bread as reference. The addition of LAGG to Jasmine rice reduced the GI value by 8% whilst the effect on long grain rice was less pronounced. Conclusions The addition of gellan gum to rice during cooking reduced starch digestion in white rice and the in-vitro glycemic index. This might be an effective way to reduce the glycemic response to starchy foods in human. Funding Sources Ministry of Education, Saudi Arabia Acknowledgment: We thank Neil Cruttenden at CPKelco for the kind gift of gellan gum.
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Orban, Tivadar, Adrian Grozav, Michael Buckys, Valentin Gogonea3, and Michael Kalafatis4. "Characterization of the Interaction between Thrombin and a Pentapeptide That Interferes with Anion Binding Exosite I of the Enzyme." Blood 104, no. 11 (November 16, 2004): 1719. http://dx.doi.org/10.1182/blood.v104.11.1719.1719.
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Abstract We have recently characterized a pentapeptide, DYDYQ, from coagulation factor V (Beck et. al. 2004J. Biol. Chem.279, 3084) that inhibits both factor V activation and prothrombinase function. The pentapeptide does not interfere with the active site of thrombin but rather interferes with substrate attachment. Our aim was to characterize at the molecular level the binding site of DYDYQ on thrombin. First we used computational methods (blind and focused docking) to propose a hypothetical binding site. Blind docking of the pentapeptide (structure obtained from a 20 ns molecular dynamics simulation) on thrombin was performed using a docking grid with large spacing. This approach provided us a favorable site (−4.8 kcal/mol) that was further investigated using a smaller spaced docking grid. Hydrogen bonding was analyzed between thrombin and DYDYQ. The final free energy of binding was −9.69 kcal/mol. Amino acids Y76R77I79I82 from thrombin anion binding exosite I (ABE-I), were identified to participate in the interaction of the enzyme with DYDYQ. We next investigated the Thrombin-DYDYQ interaction following cross-linking with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide(EDC) and mass spectrometry. In these experiments purified thrombin was inhibited in the active site with a chloromethyl ketone, and treated with the DYDYQ peptide in the presence of EDC. Two bands were observed, one corresponding to thrombin cross linked to the peptide (CT) and another band corresponding to free thrombin (T). The proteins were either (i) stained with Coomassie blue for further digestion with trypsin or (ii) transferred to nitrocellulose membranes following by staining with Coomassie blue for treatment with cyanogen bromide (CNBr). Stained bands were isolated from the gel and subjected to trypsin digestion and liquid chromatography/mass spectrometry (LC-MS). Following trypsin digestion thrombin presence in both, T and CT samples was confirmed and the peptides identified in both samples covered approximately 63% of the entire thrombin sequence. The only difference observed between the sets of peptides obtained from T and CT following digestion with trypsin, was the peptide N78IEKISM*LEK87 (M* = oxidized Methionine), which was present in the T sample but was absent in the CT sample. These results suggest that the binding site of DYDYQ to thrombin is localized in the area of the above mentioned peptide protecting it from hydrolysis by trypsin. We next analyzed T and CT by LC-MS following CNBr digestion. Three important bands (peptide products from CNBr digestion) were detected in the sample containing the T, having an approximate molecular weight of ~4,500, ~7,500, and ~9,000. CNBr digestion products of CT lacked the median band (peptide mass: ~7,500). This band corresponded to the sequence L33…Y76ERN78IEKISM84 - as confirmed by ESI-ion trap mass spectrometry amino acid sequence of its first eleven amino acid residues. The difference between the two in gel CNBr digest profiles of T and CT, confirms the conclusion drawn from the MS analysis of the triptic digests which in turn was predicted by our computational analyses. Overall our data demonstrate that 1) amino acid residues Y76R77I79I82 from thrombin provide an interactive site for DYDYQ, and 2) our results from computational methods that identify protein-peptide interaction are valid and can be confirmed by mass spectrometry.
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Momodu, Abiodun S., and Tofunmi D. Adepoju. "System dynamics kinetic model for predicting biogas production in anaerobic condition: Preliminary assessment." Science Progress 104, no. 4 (October 2021): 003685042110424. http://dx.doi.org/10.1177/00368504211042479.
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Introduction: This preliminary assessment of a grey-box model, was predicated on system dynamics principles and developed using Vensim® DSS software. The purpose is to predict biogas production under anaerobic conditions for energy utilization at the design stage. Objective: To describe the process of a developed system dynamics model to predict biogas production under anaerobic conditions. Methods: This method involves two-stage kinetics of the biogas production process in anaerobic conditions using the first-order and Gompertz functions. The model is depicted in two parts: causal loop diagram and stock–flow diagram. The causal loop diagram describes the anaerobic digestion process a substrate undergoes for the production of biogas, while stock–flow diagram depicts basic building blocks of the dynamic behavior of an anaerobic digestion process. Primary data is from a laboratory-scale experiment of biogas production using vegetal wastes, while the secondary one is from the literature on studies using similar substrates. Results: Primary and secondary data are used to validate and stimulate the developed model. The kinetic model shows the substrate being reduced exponentially with increasing time; consumption of substrate and production of methane and carbon dioxide follows exponential growth and decay pattern, with carbon dioxide production starting early compared to methane, and was produced at a rate faster due to the strong and resilient characteristics of fermentative microorganisms. Discussion: Comparing data from empirical and model simulation shows some close relationship, though not too perfectly. Both results reflect signs of inhibitions occurring within the substrates in the digester under anaerobic conditions explaining the low methane yield or instability.
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Momodu, Abiodun S., and Tofunmi D. Adepoju. "System dynamics kinetic model for predicting biogas production in anaerobic condition: Preliminary assessment." Science Progress 104, no. 4 (October 2021): 003685042110424. http://dx.doi.org/10.1177/00368504211042479.
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Introduction: This preliminary assessment of a grey-box model, was predicated on system dynamics principles and developed using Vensim® DSS software. The purpose is to predict biogas production under anaerobic conditions for energy utilization at the design stage. Objective: To describe the process of a developed system dynamics model to predict biogas production under anaerobic conditions. Methods: This method involves two-stage kinetics of the biogas production process in anaerobic conditions using the first-order and Gompertz functions. The model is depicted in two parts: causal loop diagram and stock–flow diagram. The causal loop diagram describes the anaerobic digestion process a substrate undergoes for the production of biogas, while stock–flow diagram depicts basic building blocks of the dynamic behavior of an anaerobic digestion process. Primary data is from a laboratory-scale experiment of biogas production using vegetal wastes, while the secondary one is from the literature on studies using similar substrates. Results: Primary and secondary data are used to validate and stimulate the developed model. The kinetic model shows the substrate being reduced exponentially with increasing time; consumption of substrate and production of methane and carbon dioxide follows exponential growth and decay pattern, with carbon dioxide production starting early compared to methane, and was produced at a rate faster due to the strong and resilient characteristics of fermentative microorganisms. Discussion: Comparing data from empirical and model simulation shows some close relationship, though not too perfectly. Both results reflect signs of inhibitions occurring within the substrates in the digester under anaerobic conditions explaining the low methane yield or instability.
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Dufoo-Hurtado, Elisa, Ivan Luzardo, Abraham Wall-Medrano, Guadalupe Loarca-Pina, and Rocio Campos-Vega. "Bioaccessibility and Synthesis of Chronobiotics During In Vitro Gastrointestinal Digestion of Pistachio (Pistacia vera L.) to Mitigate Diseases Linked to Chronodisruption." Current Developments in Nutrition 5, Supplement_2 (June 2021): 581. http://dx.doi.org/10.1093/cdn/nzab044_012.
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Abstract Objectives This research aimed to evaluate the in vitro chronobiotic potential of Phyto-melatonin (PTM) during gastrointestinal digestion, its fermentative behavior (phenolic acids and other compounds), and potential production of chronobiotics (short-chain fatty acids or SCFAs production). Methods The chemical and nutraceutical composition of dry roasted and salted pistachios with seed coat (SC) (PN + SC) and without (PN) was evaluated. Both samples were digested under static in vitro simulated physiological conditions comprising oral, gastric, intestinal, and colonic stages. The PTM bioaccessibility during in vitro gastrointestinal digestion and colonic fermentation simulation was quantified. The identification and quantification of SCFAs and other colonic metabolites were conducted using SPME-GC-MS, followed by an untargeted metabolomic analysis. Results PN + SC had significantly (p < 0.05) lower lipids (−7.9) and protein (−1.1), but higher carbohydrate (+8.4) and total dietary fiber (+4.8) content (g/100g) than PN. PN + SC had highest content of total phenols (+42%), total flavonoids (+54%), and PMT (+21%) (p < 0.05) compared to PN. The bioaccessibility was low for both pistachio samples [Oral: 1.92 and 3.41%, PN + SC and PN; gastric: 0.83 and 1.63%; intestinal [60 min]: 1.79 and 2.55; colonic [6 h]: 0.32 and 0.36%). Chemo-informatics and an in silico analysis of PTM suggest that it was absorbed when chewed by the participants. The highest SCFAs were produced at 12 h during in vitro colonic fermentation for both pistachio samples, where PN + SC displayed the highest (p < 0.05) value (51 mmol/L), followed by PN (25.9 mmol/L). SCFAs, derived from bacterial fermentation of dietary fibers, can act as chronobiotics in peripheral clocks. The SCFAs molar ratio remained almost constant for both pistachio samples: butyric > propionic > acetic. Some metabolites with chronobiotic potential (e.g., indole, benzaldehyde, phenolic acids, and aliphatic/aromatic hydrocarbons) were detected, sample-dependent, through the untargeted metabolomics. Conclusions Pistachio's digestion increases the bioaccessibility of PTM and the biosynthesis of colonic metabolites (SCFAs, among others), all with chronobiotic potential to mitigate diseases linked to chronodisruption. Funding Sources The funding received by CONACyT/FOPES is appreciated.
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Bonifácio-Lopes, Teresa, Marcelo D. Catarino, Ana A. Vilas-Boas, Tânia B. Ribeiro, Débora A. Campos, José A. Teixeira, and Manuela Pintado. "Impact of Circular Brewer’s Spent Grain Flour after In Vitro Gastrointestinal Digestion on Human Gut Microbiota." Foods 11, no. 15 (July 30, 2022): 2279. http://dx.doi.org/10.3390/foods11152279.
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Brewer’s spent grain (BSG) solid residues are constituted by dietary fibre, protein, sugars, and polyphenols, which can have potential effects on human health. In this study, for the first time, the flours obtained from solid residues of solid-liquid extraction (SLE) and ohmic heating extraction (OHE) were applied throughout the gastrointestinal digestion simulation (GID), in order to evaluate their prebiotic potential and in vitro human gut microbiota fermentation. The results showed that the digestion of BSG flours obtained by the different methods lead to an increase throughout the GID of total phenolic compounds (SLE: from 2.27 to 7.20 mg gallic acid/g BSG—60% ethanol:water (v/v); OHE: 2.23 to 8.36 mg gallic acid/g BSG—80% ethanol:water (v/v)) and consequently an increase in antioxidant activity (ABTS—SLE: from 6.26 to 13.07 mg ascorbic acid/g BSG—80% ethanol:water (v/v); OHE: 4.60 to 10.60 mg ascorbic acid/g BSG—80% ethanol:water (v/v)—ORAC—SLE: 3.31 to 14.94 mg Trolox/g BSG—80% ethanol:water (v/v); OHE: from 2.13 to 17.37 mg Trolox/g BSG—60% ethanol:water (v/v)). The main phenolic compounds identified included representative molecules such as vanillic and ferulic acids, vanillin and catechin, among others being identified and quantified in all GID phases. These samples also induced the growth of probiotic bacteria and promoted the positive modulation of beneficial strains (such as Bifidobacterium spp. and Lactobacillus spp.) present in human faeces. Moreover, the fermentation by human faeces microbiota also allowed the production of short chain fatty acids (acetic, propionic, and butyric). Furthermore, previous identified polyphenols were also identified during fecal fermentation. This study demonstrates that BSG flours obtained from the solid residues of SLE and OHE extractions promoted a positive modulation of gut microbiota and related metabolism and antioxidant environment associated to the released phenolic compounds.
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Anggono, Willyanto, Akihiro Hayakawa, Ekenechukwu C. Okafor, and Gabriel Jeremy Gotama. "Experimental and Numerical Investigation of Laminar Burning Velocities of Artificial Biogas Under Various Pressure and CO2 Concentration." E3S Web of Conferences 130 (2019): 01037. http://dx.doi.org/10.1051/e3sconf/201913001037.
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As a renewable and sustainable fuel made from digestion facility, biogas is composed predominantly of methane (CH4) and carbon dioxide (CO2). CO2 in biogas strongly affects its combustion characteristics. In order to develop efficient combustors for biogas, fundamental flame characteristics of biogas require extensive investigation. In understanding the influence of CO2 concentration and mixture pressure on biogas combustion, the effects of CO2 concentration on the laminar burning velocity of methane/air mixtures were studied at different pressures. The studies were conducted using both numerical and experimental methods. The experiment was conducted using a constant volume high pressure combustion chamber. The propagating flames were recorded with a high speed digital camera by employing Schlieren photography technique. The numerical simulation was carried by utilizing CHEMKIN-PRO with GRI-Mech 3.0 employed as the chemical kinetics model. The results show that the laminar burning velocity of methane-air mixtures decreased with an increase in CO2 concentration and mixture pressure. Therefore, the burning velocity of biogas mixtures may decrease as the amount of CO2 in the gas increases.
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Wichern, M., M. Lübken, M. Schlattmann, A. Gronauer, and H. Horn. "Investigations and mathematical simulation on decentralized anaerobic treatment of agricultural substrate from livestock farming." Water Science and Technology 58, no. 1 (July 1, 2008): 67–72. http://dx.doi.org/10.2166/wst.2008.332.
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Anaerobic processes are widely used for treatment of both municipal and industrial wastewater as well as agricultural substrates. In contrast to the aerobic methods, they are frequently more cost-efficient, they have a lower surplus sludge production, and the reactors can be run with higher volumetric loads and thus smaller volumes. In the paper presented both experimental data and the application of the Anaerobic Digestion Model No. 1 for agricultural substrate from livestock farming will be described. A 3,500 L reactor with mesophilic operation and loaded with cattle manure was examined with respect to its COD degradation, gas production, and gas composition. Results revealed a reduction of 30–35% COD and a biogas production of 287 LBiogas/kgVS when operated with a specific loading rate of 3.6 kgVS/(m3·d). After calibration of the ADM 1, which was based predominantly on the acetate uptake rate (kac.m=3.6 g/(g·d)), the disintegration constant (kDis=0.05 d−1) and the exact determination of the influent COD fractions contained in the agricultural substrate, it was possible to simulate the measured data of the plant in excellent quality. For future application of the ADM 1 as part of control strategies a sensitivity analysis was carried out. The analysis based on the SVM slope technique has been done to identify highly sensitive biochemical parameters. These are, amongst others, the acetate uptake rate, the disintegration constant, the biomass decay rates and the half saturation constant for ammonia inhibition. Sensitivity analysis of the inflow COD fractions (proteins, carbohydrates, lipids and inert) showed the necessity of detailed measurements for the prediction of the gas flow and composition as well as for prognosis of inhibitions in the anaerobic process. For cattle manure especially the fractions of inert material and carbohydrates should be observed carefully. Due to the high content of NH4-N in manure the protein fraction is not as sensitive as the two mentioned above.
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Abbasi, Bilal Ahmed, Devansh Saraf, Trapti Sharma, Robin Sinha, Shachee Singh, Shriya Sood, Pranjay Gupta, et al. "Identification of vaccine targets & design of vaccine against SARS-CoV-2 coronavirus using computational and deep learning-based approaches." PeerJ 10 (May 19, 2022): e13380. http://dx.doi.org/10.7717/peerj.13380.
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An unusual pneumonia infection, named COVID-19, was reported on December 2019 in China. It was reported to be caused by a novel coronavirus which has infected approximately 220 million people worldwide with a death toll of 4.5 million as of September 2021. This study is focused on finding potential vaccine candidates and designing an in-silico subunit multi-epitope vaccine candidates using a unique computational pipeline, integrating reverse vaccinology, molecular docking and simulation methods. A protein named spike protein of SARS-CoV-2 with the GenBank ID QHD43416.1 was shortlisted as a potential vaccine candidate and was examined for presence of B-cell and T-cell epitopes. We also investigated antigenicity and interaction with distinct polymorphic alleles of the epitopes. High ranking epitopes such as DLCFTNVY (B cell epitope), KIADYNKL (MHC Class-I) and VKNKCVNFN (MHC class-II) were shortlisted for subsequent analysis. Digestion analysis verified the safety and stability of the shortlisted peptides. Docking study reported a strong binding of proposed peptides with HLA-A*02 and HLA-B7 alleles. We used standard methods to construct vaccine model and this construct was evaluated further for its antigenicity, physicochemical properties, 2D and 3D structure prediction and validation. Further, molecular docking followed by molecular dynamics simulation was performed to evaluate the binding affinity and stability of TLR-4 and vaccine complex. Finally, the vaccine construct was reverse transcribed and adapted for E. coli strain K 12 prior to the insertion within the pET-28-a (+) vector for determining translational and microbial expression followed by conservancy analysis. Also, six multi-epitope subunit vaccines were constructed using different strategies containing immunogenic epitopes, appropriate adjuvants and linker sequences. We propose that our vaccine constructs can be used for downstream investigations using in-vitro and in-vivo studies to design effective and safe vaccine against different strains of COVID-19.
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Owen, E., M. C. N. Jayasuriya, R. Hamilton, and M. Lalenta. "Use of a long-term rumen simulation technique (Rusitec) to provide micro-organisms for in vitro digestibility assays." Journal of Agricultural Science 116, no. 2 (April 1991): 297–301. http://dx.doi.org/10.1017/s0021859600077716.
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SUMMARYFour experiments involving the two-stage in vitro digestibility technique of Tilley & Terry (1963) were undertaken to investigate whether cow rumen liquor could be replaced with effluent or extract from feed residue containing micro-organisms derived from the long-term rumen simulation technique (Rusitec) of Czerkawski & Breckenridge (1977).In Expts 1 and 2, the dry matter digestibility (DMD) of hay was determined using either cow rumen liquor or Rusitec liquid effluent or extract from feed after 48 h of digestion in a Rusitec apparatus using various volumes of liquor and artificial saliva. Digestibilities determined with rumen liquor were c. 70% (c.v. 1·2%) while those determined with Rusitec effluent or extract were c. 62% (c.v. 1·8%). In treatments common to Expts 1 and 2, Rusitec effluent digestibilities were more repeatable than extract or rumen liquor digestibilities.In Expts 3 and 4, Rusitec effluent was compared with cow rumen liquor for determining DMD of seven forages with DMD ranging from 33 to 70%. For a given feed there was good agreement between experiments in DMD values determined with Rusitec effluent, and for ten paired values there was a high correlation (r2 = 0·976) between DMD determined by the two methods. DMD determined using rumen liquor (y) was accurately predicted by Rusitec liquid effluent digestibility (x) from the equation y = 2·663 + 1·06477.x; R.S.D. 2·433.The results show that Rusitec liquid effluent can be used instead of rumen liquor as a source of micro-organisms for the two-stage in vitro digestibility method. Routine use of Rusitec would obviate the need for using fistulated animals.
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Gligorijevic, Nikola, Vladimir Sukalovic, Simeon Minic, Goran Miljus, Olgica Nedic, and Ana Penezic. "Physicochemical characterisation of dihydro-alpha-lipoic acid interaction with human serum albumin by multi-spectroscopic and molecular modelling approaches." Journal of the Serbian Chemical Society 86, no. 9 (2021): 795–807. http://dx.doi.org/10.2298/jsc210420041g.
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The binding of a popular food supplement and well-known antioxidant, dihydro-alpha-lipoic acid (DHLA) to human serum albumin (HSA) was characterised. The binding was monitored by several spectroscopic methods together with the molecular docking approach. HSA was able to bind DHLA with moderate affinity, 1.00?0.05?104 M-1. Spectroscopic data demonstrated that the preferential binding site for DHLA on HSA is IIA (Sudlow I). Both experimental and molecular docking analysis identified electrostatic (salt bridges) and hydrogen bonds as the key interactions involved in DHLA binding to HSA. Molecular docking confirmed that the Sudlow I site could accommodate DHLA and that the ligand is bound to the protein in a specific conformation. The molecular dynamic simulation showed that the formed complex is stable. Binding of DHLA does not affect the structure of the protein, but it thermally stabilises HSA. Bound DHLA had no effect on the susceptibility of HSA to trypsin digestion. Since DHLA is a commonly used food supplement, knowledge of its pharmacokinetics and pharmacodynamic properties in an organism is very important. This study further expands it by providing a detailed analysis of its interaction with HSA, the primary drug transporter in the circulation.
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Топаж (Topazh), Александр (Aleksandr) Григорьевич (Grigor'evich), Владимир (Vladimir) Александрович (Aleksandrovich) Вигонт (Vigont), and Любовь (Ljubov') Анатольевна (Anatol'evna) Хворова (Hvorova). "SIMULATION MODEL OF THE PROCESS OF BIOGAS PRODUCTION FROM MULTICOMPONENT PLANT RAW MATERIALS. ANALYSIS AND PARAMETRIC OPTIMIZATION." chemistry of plant raw material, no. 1 (November 14, 2017): 171–84. http://dx.doi.org/10.14258/jcprm.2018012681.
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Article is devoted to the description and the analysis of the system-dynamic model of technological process of biogas production from multicomponent vegetable raw materials. A research objective – optimization of biogas production process from vegetable raw materials by methods of imitating modeling, finding of the optimal regimes of the simulated production cycle – the best ratio from the economic point of view between an exit of biomethane and rates of giving/replacement of the initial substratum depending on the composition of raw materials.In article models with a discrete and continuous cycle of production are considered, the description of the similar realization executed in the environment of multiapproach modeling of AnyLogic for model of technological process of anaerobic digestion of non-uniform multicomponent vegetable biomass is provided.The known stoichiometric model of production of biomethane is taken as a basis, her modification is made for a case of multicomponent raw materials (percentage division into conditional components – sugar, lignin and cellulose). Possibilities of modern software shells and environments of modeling in tasks of the complex analysis and optimization of the studied process are shown.During the conducted researches a row of non-trivial results on a choice of optimum parameters of an operation mode of the model bioreactor is received. For a case of the discrete process of up-dating of contents as parameters of optimization the frequency and a level of up-dating, and for the continuous flowing system – channel speed were selected.It is shown that the optimal values of the parameters from the point of view of the integrated output of the biomethane lie close to the cloud of critical acidification, which leads to the stoppage of the process. If the economic indicators are chosen as an optimization criterion, then we obtain optimal values of the parameters lying within the region of stable functioning of the model bioreactor.
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Behle, Eric, and Adélaïde Raguin. "Stochastic model of lignocellulosic material saccharification." PLOS Computational Biology 17, no. 9 (September 13, 2021): e1009262. http://dx.doi.org/10.1371/journal.pcbi.1009262.
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The processing of agricultural wastes towards extraction of renewable resources is recently being considered as a promising alternative to conventional biofuel production. The degradation of agricultural residues is a complex chemical process that is currently time intensive and costly. Various pre-treatment methods are being investigated to determine the subsequent modification of the material and the main obstacles in increasing the enzymatic saccharification. In this study, we present a computational model that complements the experimental approaches. We decipher how the three-dimensional structure of the substrate impacts the saccharification dynamics. We model a cell wall microfibril composed of cellulose and surrounded by hemicellulose and lignin, with various relative abundances and arrangements. This substrate is subjected to digestion by different cocktails of well characterized enzymes. The saccharification dynamics is simulated in silico using a stochastic procedure based on a Gillespie algorithm. As we additionally implement a fitting procedure that optimizes the parameters of the simulation runs, we are able to reproduce experimental saccharification time courses for corn stover. Our model highlights the synergistic action of enzymes, and confirms the linear decrease of sugar conversion when either lignin content or crystallinity of the substrate increases. Importantly, we show that considering the crystallinity of cellulose in addition to the substrate composition is essential to interpret experimental saccharification data. Finally, our findings support the hypothesis of xylan being partially crystalline.
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Yang, Qianhong, Xiaolu Bai, Xiang Li, and Wei Hu. "The Identification of Key Genes and Biological Pathways in Heart Failure by Integrated Bioinformatics Analysis." Computational and Mathematical Methods in Medicine 2021 (November 26, 2021): 1–10. http://dx.doi.org/10.1155/2021/3859338.
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Purpose. Heart failure (HF) is a clinical syndrome caused by ventricular insufficiency. In order to further explore the biomarkers related to HF, we apply the high-throughput database. Materials and Methods. The GSE21610 was applied for the differentially expressed gene (DEG) analysis. The Database for Annotation, Visualization, and Integrated Discovery (DAVID) was performed to assess Gene ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. The Gene Set Enrichment Analysis (GSEA) was used for gene expression profile GSE21610. The Protein-Protein Interaction (PPI) network and modules were also constructed for research. These hub gene function pathways were estimated in HF progression. Result. We have identified 434 DEGs in total, including 304 downregulated DEGs and 130 upregulated DEGs. GO and KEGG illustrated that DEGs in HF were significantly enriched in G protein-coupled receptor binding, peroxisome, and cAMP signaling pathway. GSEA results showed gene set GSE21610 was gathered in lipid digestion, defense response to fungus, and intestinal lipid absorption. Finally, through analyzing the PPI network, we screened hub genes CDH1, TFRC, CCL2, BUB1B, and CD19 by the Cytoscape software. Conclusion. This study uses a series of bioinformatics technologies to obtain hug genes and key pathways related to HF. These analysis results provide us with new ideas for finding biomarkers and treatment methods for HF.
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Rezaei, Leila, Vali Alipour, Parisa Sharafi, Hamidreza Ghaffari, Amene Nematollahi, Vida Pesarakloo, and Yadolah Fakhri. "Concentration of cadmium, arsenic, and lead in rice (Oryza sativa) and probabilistic health risk assessment: A case study in Hormozgan province, Iran." Environmental Health Engineering and Management 8, no. 2 (March 15, 2021): 67–75. http://dx.doi.org/10.34172/ehem.2021.10.
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Background: The presence of toxic heavy metals in cereal grains like rice is one of the main human and environmental health concerns. Their importance is because of their non-biodegradability nature, high half-time, and bioaccumulation ability in the human body. Among heavy metals, cadmium (Cd), lead (Pb), and arsenic (As) are most critical, so their concentrations in rice were evaluated in this study. Methods: In this study, the concentration of Cd and Pb was determined by graphite-furnace atomic absorption spectrometer (GF-AAS), while the concentration of As was measured by atomic spectrum poll after acid digestion of the milled rice samples. The probabilistic health risk assessment of Cd, As, and Pb through consumption of different types of rice including local rice and two types imported from India (IND) and Pakistan (PAK), was estimated for the adults in Hormozgan province using Monte Carlo simulation (MCS) technique. Results: It was revealed that the concentrations of all Cd, As, and Pb in the local rice samples were lower than those in the PAK and IND samples. The average concentration of As, Pb, and Cd in the rice samples were 0.045, 0.057, and 0.022 mg/kg, respectively. The estimated total target hazard quotient (TTHQ) for this population was lower than 1, representing negligible non-carcinogenic risk through rice consumption. However, total carcinogenic risk (TCR) via As intake showed a considerable carcinogenic risk (TCR > 1E-4) for this population. Conclusion: According to the results, it is necessary to perform continuous monitoring for concentration of Cd, As, and Pb especially in the imported rice samples.
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Jin, Haihao. "Imrecoxib Inhibits Paraquat-Induced Pulmonary Fibrosis through the NF-κB/Snail Signaling Pathway." Computational and Mathematical Methods in Medicine 2020 (October 13, 2020): 1–9. http://dx.doi.org/10.1155/2020/6374014.
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Objective. In recent years, pulmonary fibrosis caused by paraquat poisoning is still concerned. However, no effective drugs have been developed yet to treat paraquat-induced pulmonary fibrosis. The aim of our research is to investigate whether imrecoxib can inhibit paraquat-induced pulmonary fibrosis and its possible mechanism. Methods. Extraction of primary pulmonary fibrosis cells (PPF cells) in vitro by the method of trypsin digestion. RT-qPCR and western blot were employed to measure the transcription level and protein expression of EMT related markers in paraquat-induced A549 cells. MTT, wound-healing, and Transwell experiments were used to verify the effect of imrecoxib on the proliferation, migration, and invasion of PPF and HFL1 cells. Results. Firstly, our results confirmed that paraquat can induce EMT and activate the NF-κB/snail signal pathway in lung epithelial cell A549. Furthermore, experimental results showed that imrecoxib could repress the proliferation, migration, and invasion of PPF and HFL1 cells. Finally, our study found that imrecoxib can inhibit EMT of paraquat-induced A549 cells by the NF-κB/snail signal pathway. Conclusion. Imrecoxib can inhibit EMT of paraquat-induced A549 cells and alleviate paraquat-caused pulmonary fibrosis through the NF-κB/snail signal pathway. Therefore, imrecoxib is a drug worthy of study in the treatment of paraquat-induced pulmonary fibrosis.
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Chitchumroonchokchai, Chureeporn, Ken Riedl, Israel Garcia Cano, Kelly Walsh, Rafael Jimenez-Flores, and Mark Failla. "Efficient In Vitro Digestion of Lipids and Proteins in Bovine Milk Fat Globule Membrane (MFGM) Ingredient and Infant Formula Containing MFGM." Current Developments in Nutrition 6, Supplement_1 (June 2022): 630. http://dx.doi.org/10.1093/cdn/nzac061.014.
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Abstract Objectives The relative immaturity of the infant digestive system after birth has the potential to affect the bioaccessibility of dietary lipids, proteins and their digested product. The in vitro digestion of lipids and protein in bovine milk fat globule membrane (MFGM) ingredient and infant formula without and with MFGM ingredient (bovine source), as well as the partitioning of non-digested and products of digestion in bioaccessible fraction of chyme were measured. Conditions that simulate those in the stomach and small intestine of infants were used. Methods MFGM ingredient and whey/casein-based infant formula with and without 6%MFGM ingredient were digested using static, two-phase in vitro digestion model with conditions simulating those in the infant gut. Digestion and bioaccessibility of lipids were monitored by measuring a wide lipid profile using direct infusion-mass spectrometry (DI-MS/MS). Digestion of proteins were determined by denaturing polyacrylamide gel electrophoresis, with quantitative imaging of all blue stained bands. Results Cholesterol esters, diacylglycerides, triacylglycerides, phosphatidylcholines, and phosphatidylethanolamines in the MFGM ingredients were readily hydrolyzed resulting in marked increases in the amounts of free fatty acids and lyso-phospholipids in the bioaccessible fraction of chyme. In contrast, sphingomyelins, ceramides and GM3 gangliosides were relatively resistant to digestion. Protein in MFGM ingredient and infant formula without and with added MFGM ingredient also were efficiently digested. Conclusions The results suggest proteins, neutral lipids and phospholipids in MFGM are efficiently digested using conditions that simulate those in the prandial lumen of the stomach and small intestine of infants. Also, the profile of lipid and protein digestion is similar for whey/casein-based infant formula without and with MFGM ingredient using conditions that simulate those in the infant gut. Funding Sources Ohio State Agriculture Research and Development Center, the JT Parker Endowment and Reckitt Nutrition Institute.
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Li, Yan, Li Li, Hua Zhao, Xiwen Gao, and Shanqun Li. "Identifying Obstructive Sleep Apnea Syndrome-Associated Genes and Pathways through Weighted Gene Coexpression Network Analysis." Computational and Mathematical Methods in Medicine 2022 (January 29, 2022): 1–13. http://dx.doi.org/10.1155/2022/3993509.
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Background. Obstructive sleep apnea syndrome (OSAS) is the most common type of sleep apnea disorder. The disease seriously affects the patient’s respiratory system. At present, the prognosis of the disease is poor and there is a lack of effective treatments. Therefore, it is urgent to explore its pathogenesis and treatment methods. Method. We downloaded a set of expression profile data from GSE75097 related to OSAS based on the Gene Expression Omnibus (GEO) database and selected the representative differentially expressed genes (DEGs) from the sample of the GSE75097 dataset. WGCNA was used to find genes related to OSAS and obtain coexpression modules. The Gene Ontology (GO) function and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway were used to analyze genes from key modules. Finally, Cytoscape software was used to construct a protein-protein interaction (PPI) network and analyze the hub genes. Result. We obtained a total of 7565 DEGs. Through WGCNA, we got four coexpression modules and the modules most related to OSAS were green-yellow, magenta, purple, and turquoise, and we screened out eight hub genes (DDX46, RNF115, COPA, FBXO4, PA2G4, NHP2L1, CDC20, and PCNA). GO and KEGG analyses indicated that the key modules were mainly enriched in tRNA modification, nucleobase metabolic process, DNA ligation, regulation of cellular component movement, basal transcription factors, Huntington disease, and vitamin digestion and absorption. Conclusion. These pathways and hub genes can facilitate understanding the molecular mechanism of OSAS and provide a meaningful reference for finding biological targets of OSAS treatment.
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Zablodskiy, N., and М. Spodoba. "DETERMINATION OF ENERGY EFFICIENT LEVEL OF THE SPEED OF MIXING BODY OF ELECTROMECHANICAL SYSTEM." Electromechanical and energy saving systems 4, no. 52 (December 23, 2020): 17–26. http://dx.doi.org/10.30929/2072-2052.2020.4.52.17-26.
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Purpose. Today, biomass fermentation in biogas plants is one of the most advanced, environmentally and economically viable solutions for energy production from waste. However, the process of anaerobic digestion of waste is long, so the main process of intensification is mixing. Analysis of well-known studies of domestic and foreign scientists indicates the urgency of reducing energy consumption for the mixing process. The aim of the study is to determine the energy-efficient speed of a paddle stirrer with blades set at an angle of 450 for small biogas reactors. Methodology. At the decision of the set tasks the general methods of physics, three-dimensional modeling, processing and visualization of the received results in the SolidWorks Flow Simulation and Wolfram Mathematica programs are applied. Results. Using 3D modeling, the influence of the stirrer speed on the picture of the distribution of the velocity vectors of the substrate flows in the biogas reactor was studied. Graphs of power consumption at the beginning of mixing for different stirrer speeds were obtained and analyzed, and the levels of energy consumed for mixing biomass during the start-up period and the whole mixing period were compared. A method for determining the energy efficient rotation speed of the stirring mechanism of the electromechanical system of biogas reactors is proposed. Practical value. The results can be used in the construction and modernization of biogas plants to reduce energy consumption of the substrate mixing process. Conclusion. Based on the research, it was concluded that for a paddle two-tier mixer with blades set at an angle of 450 energy-efficient speed, is 40 rpm. At this speed, careful and intensive mixing of the biomass is observed throughout the volume of the tank. The average velocity of flow vectors in the biomass volume is 0,273 m/s. The energy consumed per cycle of biomass mixing is 2471,3 J, and the percentage of energy consumed during the start-up period from the energy consumed during the entire mixing period is 0,62 %. References 19, figures 5.
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Castillo, Cristina, and Joaquin Hernández. "Ruminal Fistulation and Cannulation: A Necessary Procedure for the Advancement of Biotechnological Research in Ruminants." Animals 11, no. 7 (June 23, 2021): 1870. http://dx.doi.org/10.3390/ani11071870.
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Rumen content is a complex mixture of feed, water, fermentation products, and living organisms such as bacteria, fungi, and protozoa, which vary over time and with different feeds. As it is impossible to reproduce this complex system in the laboratory, surgical fistulation and cannulation of the rumen is a powerful tool for the study (in vivo and in situ) of the physiology and biochemistry of the ruminant digestive system. Rumen fistulation in cattle, sheep, and goats has been performed extensively to advance our understanding of digestive physiology and development, nutrient degradability, and rumen microbial populations. The literature reports several fistulation and cannulation procedures in ruminants, which is not the focus of this paper. However, this method questions the ethical principles that alter the opinions of certain animal groups or those opposed to animal experimentation. In this article, we analyze the objectives of fistulation and cannulation of ruminants and the care needed to ensure that the welfare of the animal is maintained at all times. Due to the ethical issues raised by this technique, several in vitro digestion methods for simulating ruminal fermentation have been developed. The most relevant ones are described in this article. Independently of the procedure, we want to point out that research carried out with animals is obliged by legislation to follow strict ethical protocols, following the well-being and health status of the animal at all times.
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Tso, Ju, Fan, and Chiang. "Enzyme Degradation Reagents Effectively Remove Mycotoxins Deoxynivalenol and Zearalenone from Pig and Poultry Artificial Digestive Juices." Toxins 11, no. 10 (October 15, 2019): 599. http://dx.doi.org/10.3390/toxins11100599.
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Mycotoxin removers include enzymes and adsorbents that may be used in animal feeds to eliminate the toxic effects of mycotoxins. This study aimed to determine the removability of two different types of mycotoxin removers, adsorbents and enzyme degradation reagents (EDRs), in the simulated gastrointestinal conditions of pigs and poultry. Seven commercial mycotoxin removers, including five EDRs and two adsorbents, were tested in vitro. In this study, the supplemented dosages of mycotoxin removers used in pig and poultry feeds were the commercial recommendation ranging from 0.05% to 0.2%. For pigs, the in vitro gastric and small intestinal simulations were performed by immersing the mycotoxin-tainted feed in artificial gastric juice (AGJ) at pH 2.5 for 5 h or in artificial intestinal juice (AIJ) at pH 6.5 for 2 h to mimick in vivo conditions. For poultry, mycotoxin-tainted feeds were immersed in AGJ for 2 h at pH 4.5 and 0.5 h at pH of 2.5, respectively, to simulate crop/glandular stomach and gizzard conditions; the small intestinal simulation was in AIJ for 2 h at pH 6.5. For the pig, EDRs and adsorbents had deoxynivalenol (DON) removability (1 mg/kg) of 56% to 100% and 15% to 19%, respectively. Under the concentration of 0.5 mg/kg, the zearalenone (ZEN) removability by EDRs and adsorbents was 65% to 100% and 0% to 36%, respectively. For the simulation in poultry, the removability of DON by EDRs and adsorbents (5 mg/kg) was 56% to 79% and 1% to 36%, respectively; for the concentration of 0.5 mg/kg, the removability of ZEN by EDRs and adsorbents was 38% to 69% and 7% to 9%, respectively. These results suggest that EDRs are more effective in reducing DON and ZEN contamination compared to the adsorbent methods in the simulated gastrointestinal tracts of pig and poultry. The recoveries of DON and ZEN of pig in vitro gastrointestinal simulations were higher than 86.4% and 84.7%, respectively, with 88.8% and 85.9%, respectively, in poultry. These results demonstrated the stability and accuracy of our mycotoxin extraction process and in vitro simulation efficiency.
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Putra, Christianto, Dhimiter Bello, Katherine Tucker, Shannon Kelleher, and Kelsey Mangano. "Dietary Intake and Fecal Excretion of Titanium Dioxide in U.S. Adults From Lowell, Massachusetts." Current Developments in Nutrition 5, Supplement_2 (June 2021): 1082. http://dx.doi.org/10.1093/cdn/nzab053_075.
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Abstract Objectives Engineered nanomaterials, such as titanium dioxide (TiO2/E171) are used in food primarily as a whitening agent. Over 99% ingested TiO2 passes to the gastrointestinal (GI) tract while 1% is absorbed and shown to bioaccumulate in organs and may cause adverse outcomes. At present, dietary exposure of TiO2 in the US is unknown. The objective is to estimate dietary TiO2 and measure TiO2 output in matched stool samples as a biological marker of intake. Methods Participants (n = 51), aged 18–30 y, were recruited in Lowell, MA and were eligible if they had not taken laxatives/antibiotics in the past 6 mo, free of GI disease and no history of GI alterations. Recent dietary intake was assessed by 3, 24-h recalls (NDSR2019) and estimated TiO2 intake is presented as the average of the 3 days. A published database of TiO2 content in foods (Netherlands), with extrapolations for similar US foods, was used to estimate TiO2 exposure. To capture TiO2 excretion, stool samples (n = 3) were collected the same day of diet recall. TiO2 was measured in reported foods suspected to contain TiO2 to improve the database. Concentrations of TiO2 in food and stool samples were measured using inductively coupled plasma mass spectrometry following acid digestion. Results Mean age was 23 ± 3 y; BMI 27 ± 5 kg/m2; 52.9% female. Mean estimated TiO2 intake was 0.13 ± 0.28 mg/kgbw/d (median: 0.03; range: 0.01–1.63 mg/kgbw/d). Mean measured TiO2 concentration in stool samples was 0.107 ± 0.134 mg/mg (median: 0.043; range: 0.005–0.536 ug/mg). Food analysis showed TiO2 content varies widely and is dependent on brand. The top 5 contributors to TiO2 intake in this sample were frostings (62.2%), sauces (8.7%), grains (5.3%), chewing gum (4.43%), and commercial desserts – miscellaneous (3.3%). No association was observed between reported TiO2 intake and measured stool concentration. Conclusions To our knowledge, this is the first study to assess dietary TiO2 in the US using a validated dietary method and stool excretion. Estimated TiO2 intakes were similar to those in the Netherlands (0.17 mg/kgbw/d), but lower than previous estimates for the US, via Monte Carlo simulation (0.7 mg/kgbw/d). Improvement in the food database is needed to study the effects of chronic TiO2 intake on health outcomes, such as gut health and the microbiome. Funding Sources None.
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Lu, Jun, Ruichao Li, Minghao Fang, and Shun Ke. "Hub Genes and Long Noncoding RNAs That Regulates It Associated with the Prognosis of Esophageal Squamous Cell Carcinoma Based on Bioinformatics Analysis." Computational and Mathematical Methods in Medicine 2022 (September 19, 2022): 1–11. http://dx.doi.org/10.1155/2022/6027058.
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Objective. Through bioinformatics analysis methods, the public databases GEO and TCGA were used to research mRNA and squamous cell carcinoma of the esophagus, construct a lncRNA-mRNA network, and screen hub genes and lncRNAs related to prognosis. Method. Download esophageal squamous cell carcinoma-related mRNA and lncRNA datasets GEO and TCGA public datasets, as well as clinical data, use bioinformatic tools to perform gene differential expression analysis on the datasets to obtain differentially expressing mRNA (DEmRNA) and lncRNA (DElncRNA), and plot volcano plots and cluster heatmaps. The differential intersection of differentially expressed DEmRNA and DElncRNA was extracted by Venn diagram and imported into CytoScape software, a regulatory network visualization software, to construct a lncRNA-mRNA network and use cytoHubba and MCODE plug-ins to screen hub genes and key lncRNAs. The DEmRNA in the network was imported into the Gene and Protein Interaction Retrieval Database (STRING), gene-encoded protein–protein interactions (PPI) network maps were created, and the genes in the PPI network maps were submitted to GO functional annotation and pathway enrichment analysis using Kyoto Encyclopedia of Gene Genomes (KEGG) (KEGG). The link between hub gene and prognosis was studied using the clinical data collected by TCGA. Result. Retrieve the datasets GSE23400 and GSE38129 from the GEO database and the esophageal squamous cell carcinoma-related mRNAs from TCGA databases and then obtain intersection. Differentially regulated genes revealed a correlation of 326 (up) with 191 (down) in terms of the differential intersection; for this study, we need to collect the GSE130078 dataset from GEO, as well as the lncRNAs from TCGA databases that are connected to esophageal squamous cell cancer. There were 184 differentially up- and downregulated genes in the differential intersection. A differential intersection network of the differential intersection lncRNA-mRNA network allowed us to identify the hub genes, including COL5A2 (COL3A1), COL1A1 (COL1A1), CTD-2171N6.1 (CTD-2171N6.1), and RP11-863P13.3 (RP11-863P13.3). The extracellular matrix, which is important in protein digestion and absorption, was shown to be the primary site of functional enrichment, as shown by GO/KEGG analysis. Squamous cell carcinoma of the mouth and throat is associated with a poor prognosis because of a change in the extracellular matrix structure caused by specific long noncoding RNA (lncRNA) regulatory upregulation. Conclusion. For the purpose of predicting the prognosis of cancer of the esophagus, researchers studied the esophageal squamous cell carcinoma-related hub genes and important noncoding RNAs (ncRNAs).
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Vrca, Ivana, Franko Burčul, Ivica Blažević, Andre Bratanić, and Tea Bilušić. "Comparison of gastrointestinal stability of isothiocyanates from Tropaeolum Majus L. Altum using in vitro and ex vivo digestion methods." Croatian journal of food science and technology 13, no. 2 (December 15, 2021): 160–66. http://dx.doi.org/10.17508/cjfst.2021.13.2.04.
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Tropaeolum majus L. is an annual herbaceous plant and a member of the Tropaeolaceae family, which belongs to the Brassicales order. It is an excellent source of flavonoids, carotenoids, phenolic acids, vitamin C, and it is a plant that contains the glucosinolate glucotropaeolin. The major degradation product of glucotropaeolin is benzyl isothiocyanate which is known for its various biological activities. In this study, an essential oil was isolated from the seeds of the Tropaeolum majus L. altum plant by microwave-assisted distillation and analysed using the GC-MS technique. Two compounds were identified, benzyl isothiocyanate as the major one (97.81%), and 2-phenylacetonitrile as a minor one (0.80%). Tropaeolum majus L. altum essential oil and pure benzyl isothiocyanate were then submitted to the two-phase in vitro and ex vivo digestion simulations. The analysis performed by the GC-MS/MS technique showed greater stability of benzyl isothiocyanate from essential oil after in vitro (97.57%), and ex vivo (73.47%) gastric phases of the simulated digestion methods, compared to its stability after in vitro (71.17%) and ex vivo (54.90%) intestinal phases. A similar trend was shown for pure benzyl isothiocyanate.
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Woolnough, James W., John A. Monro, Charles S. Brennan, and Anthony R. Bird. "Simulating human carbohydrate digestionin vitro: a review of methods and the need for standardisation." International Journal of Food Science & Technology 43, no. 12 (December 2008): 2245–56. http://dx.doi.org/10.1111/j.1365-2621.2008.01862.x.
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Jiang, Xingyu, Qi Liang, Huanhuan Xu, Shouyong Gu, and Lingxiang Liu. "The Association of Waist Circumference with the Prevalence and Survival of Digestive Tract Cancer in US Adults: A Population Study Based on Machine Learning Methods." Computational and Mathematical Methods in Medicine 2022 (October 6, 2022): 1–11. http://dx.doi.org/10.1155/2022/2492488.
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Aims. This paper aims to investigate the relationship of waist circumference (WC) with digestive tract cancer morbidity and mortality. Methods. Based on the data from a nationally representative US population survey, we summarized the prevalence of digestive tract cancer and all-cause mortality of cancer patients across WC quartiles. Adjusted logistic regression and restricted spline curve were used to analyze WC and the prevalence of digestive tract cancer. Moreover, Cox regression and the Kaplan-Meier curve were applied to investigate the association of WC with all-cause mortality. We also attempted to make a model to predict cancer happening. Results. This paper included a total of 34,041 participants, with digestive tract cancer observed in 265 (0.7%) individuals. WC was positively associated with digestive tract cancer morbidity after full adjustment of covariates (OR: 1.72 and 95% CI: 1.41-2.10). Also, individuals in the highest WC group had a higher risk of digestive tract cancer (Q4, OR: 2.71 and 95% CI: 1.48-5.00). Moreover, no significant association was observed in upper digestive cancer, and WC was associated with a longer survival time once diagnosed (hazard ratio (HR): 0.50 and 95% CI: 0.28-0.92). Finally, the model we made proved to be effective. Conclusion. High WC is a risk factor for digestive tract cancer with or without adjusting for body mass index, especially those located in the lower digestive tract. However, once digestive tract cancer has been diagnosed, patients with higher WC showed better survival outcomes. Moreover, machine learning methods can be used to predict digestive tract cancer risk in the future.
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Sandberg, Ann-Sofie. "Methods and Options for in vitro Dialyzability; Benefits and Limitations." International Journal for Vitamin and Nutrition Research 75, no. 6 (November 1, 2005): 395–404. http://dx.doi.org/10.1024/0300-9831.75.6.395.
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In vitro dialyzability methods involve a two-step digestion process simulating the gastric and intestinal phase, and dialysis through a semi-permeable membrane with a selected molecular weight cut-off. Dialyzable iron/zinc is used as an estimation of available mineral. Final pH adjustment and use of a strict time schedule were found to be critical factors for standardization. In addition the selected cut-off of the dialysis membrane and the method used for iron and zinc determination influence the results. For screening purposes, simple solubility or dialyzability methods seem preferable to the more sophisticated computer-controlled gastrointestinal model. This is likely more valuable in studies of different transit times and sites of dialyzability. In vitro solubility/dialyzability methods correlate in most cases with human absorption studies in ranking iron and zinc availability from different meals. Exceptions may be that effects of milk, certain proteins, tea, and organic acids cannot be predicted. The dialyzability methods exclude iron bound to large molecules, which in some cases is available and include iron bound to small molecules, which is not always available. In vitro experiments based on solubility/dialyzability are tools to understand factors that may affect subsequent mineral absorption.
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An, Yan Ming, Lian Qin He, Guo Zhong Zhao, Ming Fei An, and Yue Zhen. "Study of Computer Aided History Matching Technology." Advanced Materials Research 271-273 (July 2011): 275–80. http://dx.doi.org/10.4028/www.scientific.net/amr.271-273.275.
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On the basic of studying the present technical situation of home and abroad about computer aided History Matching of the reservoir numerical simulation and digesting, absorbing technology, we studied and optimized highly effective algorithm fit for the aided History Matching. At the same time, we designed the software interface and frame and function module, developed the independent aided History Matching software named CAPHE, thus formed aided history methods suitable for our independent reservoir simulator-PBRS. By using of the software in practical some oil simulation blocks, CAPHE can significantly increase History Matching efficiency in the reservoir simulation.
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Meyer, Jesse G. "In Silico Proteome Cleavage Reveals Iterative Digestion Strategy for High Sequence Coverage." ISRN Computational Biology 2014 (April 22, 2014): 1–7. http://dx.doi.org/10.1155/2014/960902.
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In the postgenome era, biologists have sought to measure the complete complement of proteins, termed proteomics. Currently, the most effective method to measure the proteome is with shotgun, or bottom-up, proteomics, in which the proteome is digested into peptides that are identified followed by protein inference. Despite continuous improvements to all steps of the shotgun proteomics workflow, observed proteome coverage is often low; some proteins are identified by a single peptide sequence. Complete proteome sequence coverage would allow comprehensive characterization of RNA splicing variants and all posttranslational modifications, which would drastically improve the accuracy of biological models. There are many reasons for the sequence coverage deficit, but ultimately peptide length determines sequence observability. Peptides that are too short are lost because they match many protein sequences and their true origin is ambiguous. The maximum observable peptide length is determined by several analytical challenges. This paper explores computationally how peptide lengths produced from several common proteome digestion methods limit observable proteome coverage. Iterative proteome cleavage strategies are also explored. These simulations reveal that maximized proteome coverage can be achieved by use of an iterative digestion protocol involving multiple proteases and chemical cleavages that theoretically allow 92.9% proteome coverage.
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Buaduang, Nootjaree, Worrapanit Chansuwan, Nongporn Hutadilok Towatana, Zhe Yang, and Nualpun Sirinupong. "Tilapia Protein Hydrolysate Enhances Transepithelial Calcium Transport in Caco2 cells." Functional Foods in Health and Disease 9, no. 10 (October 31, 2019): 678. http://dx.doi.org/10.31989/ffhd.v9i10.651.
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Background: Potent calcium uptake is essential for calcium balance and normal health. Prolonged low intake of calcium is associated with osteoporosis, dental changes, cataracts, and alterations in the brain. However, calcium is difficult to be directly absorbed from the food due to the insoluble calcium salt precipitation that occurs in the intestinal environment. Methods: Tilapia protein hydrolysate (TPH) was prepared by alcalase digestion. The Calcium-binding activity was measured using calcium colorimetric assay, the absorption at 612 nm. The interaction between TPH and calcium was examined by spectroscopic analysis, ultraviolet absorption and fluorescence measurement. TPH-calcium-binding stability in the human digestion system was evaluated by in vitro pepsin-pancreatin hydrolysis simulating human gastric and intestinal digestion. The effects of food components on TPH-calcium-binding activity was also analyzed. The enhancement of transepithelial calcium transport by TPH was determined by in vitro Caco2 epithelial cell-like monolayer. Results: TPH produced from Nile tilapia (Oreochromis niloticus) exhibited calcium-binding activity. It was the peptides in the hydrolysate that contributed to calcium-binding since the spectroscopic changes induced by calcium were characteristic of peptide bonds and tryptophan residues. The calcium binding of TPH was compatible with food matrices. Most food components including saccharides, amino acids and vitamins showed positive or no effects on calcium-binding. The calcium-binding of TPH was also stable in the simulated gastrointestinal digestion system. Pepsin and pancreatin did not considerably change the calcium-binding activity of TPH. Of note, TPH reduced precipitation of calcium by oxalate and phytate, the two most anti-nutritional factors present in green leafy vegetables. Finally, we showed that TPH significantly promoted transepithelial calcium transport in the Caco-2 cell permeability model. Conclusions: Tilapia protein hydrolysate produced by alcalase digestion possessed calcium-binding activity and prevent precipitation of calcium by a mineral chelating agent as well as enhanced transepithelial calcium transport in Caco2 cell. The result implicated the potential of TPH as a functional food ingredient for promoting calcium absorption. Keywords: Tilapia protein hydrolysate; Calcium binding peptides; Calcium absorption
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Muralha, Nuno, Manuel Oliveira, Maria Amélia Ferreira, and José Costa-Maia. "Virtual Reality Simulation as a Tool to Monitor Surgical Performance Indicators: VIRESI Observational Study." Acta Médica Portuguesa 30, no. 5 (May 31, 2017): 388. http://dx.doi.org/10.20344/amp.7983.
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Introduction: Virtual reality simulation is a topic of discussion as a complementary tool to traditional laparoscopic surgical training in the operating room. However, it is unclear whether virtual reality training can have an impact on the surgical performance of advanced laparoscopic procedures. Our objective was to assess the ability of the virtual reality simulator LAP Mentor to identify and quantify changes in surgical performance indicators, after LAP Mentor training for digestive anastomosis.Material and Methods: Twelve surgeons from Centro Hospitalar de São João in Porto (Portugal) performed two sessions of advanced task 5: anastomosis in LAP Mentor, before and after completing the tutorial, and were evaluated on 34 surgical performance indicators.Results: The results show that six surgical performance indicators significantly changed after LAP Mentor training. The surgeons performed the task significantly faster as the median ‘total time’ significantly reduced (p < 0.05) from 759.5 to 523.5 seconds. Significant decreases (p < 0.05) were also found in median ‘total needle loading time’ (303.3 to 107.8 seconds), ‘average needle loading time’ (38.5 to 31.0 seconds), ‘number of passages in which the needle passed precisely through the entrance dots’ (2.5 to 1.0), ‘time the needle was held outside the visible field’ (20.9 to 2.4 seconds), and ‘total time the needle-holders’ ends are kept outside the predefined operative field’ (88.2 to 49.6 seconds).Discussion: This study raises the possibility of using virtual reality training simulation as a benchmark tool to assess the surgical performance of Portuguese surgeons.Conclusion: LAP Mentor is able to identify variations in surgical performance indicators of digestive anastomosis.
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Patel, Chandan, and Dipankar Roy. "A Computational Study of Molecular Mechanism of Chloroquine Resistance by Chloroquine Resistance Transporter Protein of Plasmodium falciparum via Molecular Modeling and Molecular Simulations." Physchem 1, no. 3 (October 14, 2021): 232–42. http://dx.doi.org/10.3390/physchem1030017.
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The molecular mechanism of chloroquine resistance by the chloroquine resistance transporter protein of Plasmodium sp. is explored using molecular modeling and computational methods. The key mutation, lysine(K)-76 to threonine(T) (LYS76THR) in the transporter protein pertains to increased recognition of the protonated forms of the antimalarial drug. Such enhanced affinity can promote drug efflux from host digestive vacuole, rendering aminoquinoline-based treatment ineffective.