15 research outputs found

    Numerical analysis of initial amount of substrate and biomass in substrate inhibition process

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    -The process of inhibition of enzymes is important because it serves as a fundamental control mechanism in many biological systems and allows the regulation of metabolic pathways. In fact, many medications act by inhibiting specific enzymes in the brain or in body tissues. Therefore, the understanding of enzymatic inhibition mechanism is, essential. Inhibitors are frequently used as tools for the study of the mechanism of the enzymes themselves. In the present paper we have studied the process of substrate inhibition by developing a mathematical model that allow us to understand the influence of initial amount of substrate and initial biomass concentration on maximum growth rate value. Numerical analysis using Matlab software was performed to model this inhibition process. © 2018, World Scientific and Engineering Academy and Society. All rights reserved

    Global, regional, and national incidence, prevalence, and years lived with disability for 354 diseases and injuries for 195 countries and territories, 1990-2017: a systematic analysis for the Global Burden of Disease Study 2017.

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    The Global Burden of Diseases, Injuries and Risk Factors 2017 includes a comprehensive assessment of incidence, prevalence, and years lived with disability (YLDs) for 354 causes in 195 countries and territories from 1990 to 2017. Previous GBD studies have shown how the decline of mortality rates from 1990 to 2016 has led to an increase in life expectancy, an ageing global population, and an expansion of the non-fatal burden of disease and injury. These studies have also shown how a substantial portion of the world's population experiences non-fatal health loss with considerable heterogeneity among different causes, locations, ages, and sexes. Ongoing objectives of the GBD study include increasing the level of estimation detail, improving analytical strategies, and increasing the amount of high-quality data. METHODS: We estimated incidence and prevalence for 354 diseases and injuries and 3484 sequelae. We used an updated and extensive body of literature studies, survey data, surveillance data, inpatient admission records, outpatient visit records, and health insurance claims, and additionally used results from cause of death models to inform estimates using a total of 68 781 data sources. Newly available clinical data from India, Iran, Japan, Jordan, Nepal, China, Brazil, Norway, and Italy were incorporated, as well as updated claims data from the USA and new claims data from Taiwan (province of China) and Singapore. We used DisMod-MR 2.1, a Bayesian meta-regression tool, as the main method of estimation, ensuring consistency between rates of incidence, prevalence, remission, and cause of death for each condition. YLDs were estimated as the product of a prevalence estimate and a disability weight for health states of each mutually exclusive sequela, adjusted for comorbidity. We updated the Socio-demographic Index (SDI), a summary development indicator of income per capita, years of schooling, and total fertility rate. Additionally, we calculated differences between male and female YLDs to identify divergent trends across sexes. GBD 2017 complies with the Guidelines for Accurate and Transparent Health Estimates Reporting

    Global, regional, and national incidence, prevalence, and years lived with disability for 354 diseases and injuries for 195 countries and territories, 1990-2017: a systematic analysis for the Global Burden of Disease Study 2017

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    The Global Burden of Diseases, Injuries, and Risk Factors Study 2017 (GBD 2017) includes a comprehensive assessment of incidence, prevalence, and years lived with disability (YLDs) for 354 causes in 195 countries and territories from 1990 to 2017. Previous GBD studies have shown how the decline of mortality rates from 1990 to 2016 has led to an increase in life expectancy, an ageing global population, and an expansion of the non-fatal burden of disease and injury. These studies have also shown how a substantial portion of the world's population experiences non-fatal health loss with considerable heterogeneity among different causes, locations, ages, and sexes. Ongoing objectives of the GBD study include increasing the level of estimation detail, improving analytical strategies, and increasing the amount of high-quality data.; We estimated incidence and prevalence for 354 diseases and injuries and 3484 sequelae. We used an updated and extensive body of literature studies, survey data, surveillance data, inpatient admission records, outpatient visit records, and health insurance claims, and additionally used results from cause of death models to inform estimates using a total of 68 781 data sources. Newly available clinical data from India, Iran, Japan, Jordan, Nepal, China, Brazil, Norway, and Italy were incorporated, as well as updated claims data from the USA and new claims data from Taiwan (province of China) and Singapore. We used DisMod-MR 2.1, a Bayesian meta-regression tool, as the main method of estimation, ensuring consistency between rates of incidence, prevalence, remission, and cause of death for each condition. YLDs were estimated as the product of a prevalence estimate and a disability weight for health states of each mutually exclusive sequela, adjusted for comorbidity. We updated the Socio-demographic Index (SDI), a summary development indicator of income per capita, years of schooling, and total fertility rate. Additionally, we calculated differences between male and female YLDs to identify divergent trends across sexes. GBD 2017 complies with the Guidelines for Accurate and Transparent Health Estimates Reporting. Globally, for females, the causes with the greatest age-standardised prevalence were oral disorders, headache disorders, and haemoglobinopathies and haemolytic anaemias in both 1990 and 2017. For males, the causes with the greatest age-standardised prevalence were oral disorders, headache disorders, and tuberculosis including latent tuberculosis infection in both 1990 and 2017. In terms of YLDs, low back pain, headache disorders, and dietary iron deficiency were the leading Level 3 causes of YLD counts in 1990, whereas low back pain, headache disorders, and depressive disorders were the leading causes in 2017 for both sexes combined. All-cause age-standardised YLD rates decreased by 3·9% (95% uncertainty interval [UI] 3·1-4·6) from 1990 to 2017; however, the all-age YLD rate increased by 7·2% (6·0-8·4) while the total sum of global YLDs increased from 562 million (421-723) to 853 million (642-1100). The increases for males and females were similar, with increases in all-age YLD rates of 7·9% (6·6-9·2) for males and 6·5% (5·4-7·7) for females. We found significant differences between males and females in terms of age-standardised prevalence estimates for multiple causes. The causes with the greatest relative differences between sexes in 2017 included substance use disorders (3018 cases [95% UI 2782-3252] per 100 000 in males vs s1400 [1279-1524] per 100 000 in females), transport injuries (3322 [3082-3583] vs 2336 [2154-2535]), and self-harm and interpersonal violence (3265 [2943-3630] vs 5643 [5057-6302]). Global all-cause age-standardised YLD rates have improved only slightly over a period spanning nearly three decades. However, the magnitude of the non-fatal disease burden has expanded globally, with increasing numbers of people who have a wide spectrum of conditions. A subset of conditions has remained globally pervasive since 1990, whereas other conditions have displayed more dynamic trends, with different ages, sexes, and geographies across the globe experiencing varying burdens and trends of health loss. This study emphasises how global improvements in premature mortality for select conditions have led to older populations with complex and potentially expensive diseases, yet also highlights global achievements in certain domains of disease and injury

    Integration of yield factor expression into Haldane's model for substrate inhibition.

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    Haldane equation is a mathematical expression that has been widely used in growth kinetics to give a proper fit to experimental data in case of substrate inhibition during enzymatic processes. It determines the specific growth rate of a microorganism based on the substrate concentration, the half saturation constant, the inhibitory constant and the maximum growth rate achievable. However, for practical and experimental design purposes it is important to describe Haldane equation in terms of the initial concentration of substrate, since this information is required to know the proper amount of initial substrate to be used. For this reason, in the present paper we proposed to integrate the expression of yield factor and the definition of specific growth rate in a batch system into Haldane's equation and to solve analytically the mathematical equations in order to obtain a final expression that correlates the maximum growth rate, the limiting nutrient concentration at which the specific growth is half its maximum value, the inhibitory constant, the initial concentration of substrate and the initial amount of biomass required in time. Accordingly, simulation and numerical studies are presented to analyze and discuss the importance of the obtained model. © 2018 The Authors, published by EDP Sciences.Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [L01303 (MSMT-7778/2014)]; Eumpean Regional Development Fund under the project CEB1A-Tech [C,Z.1.05/2.1.00/03.0089]; Lac Hong University in Vietna

    Use of phosphates in meat products

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    Phosphates offer a range of possibilities when used in meat and poultry productions. Food grade phosphates are used in meat products for several reasons such as changing and/or stabilizing of pHvalue, increasing water holding capacity in order to lead to higher yields, decreasing losses of weight in cooking, improving texture and sensory properties (tenderness, juiciness, color and flavor), extending shelf-life, etc. In addition, phosphates in meat products are also sources of the supply of phosphorus for consumers through diet, which is an essential mineral for the lives of humans. This review is focused on phosphates' properties, functions, application in meat and poultry products as well as influence on health. © 2011 Academic Journals

    Study of parameters affecting the conversion in a plug flow reactor for reactions of the type 2A→B

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    Modeling of chemical reactors is an important tool to quantify reagent conversion, product yield and selectivity towards a specific compound and to describe the behavior of the system. Proposal of differential equations describing the mass and energy balance are among the most important steps required during the modeling process as they play a special role in the design and operation of the reactor. Parameters governing transfer of heat and mass have a strong relevance in the rate of the reaction. Understanding this information is important for the selection of reactor and operating regime. In this paper we studied the irreversible gas-phase reaction 2A→B. We model the conversion that can be achieved as function of the reactor volume and feeding temperature. Additionally, we discuss the effect of activation energy and the heat of reaction on the conversion achieved in the tubular reactor. Furthermore, we considered that dimerization occurs instantaneously in the catalytic surface to develop equations for the determination of rate of reaction per unit area of three different catalytic surface shapes. This data can be combined with information about the global rate of conversion in the reactor to improve regent conversion and yield of product. © 2018 Author(s).Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [LO1303 (MSMT-7778/2014)]; European Regional Development Fund under the project CEBIA [CZ.1.05/2.1.00/03.0089]; Lac Hong University in Vietna

    Integration of yield factor expression into Haldane’s model for substrate inhibition.

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    Haldane equation is a mathematical expression that has been widely used in growth kinetics to give a proper fit to experimental data in case of substrate inhibition during enzymatic processes. It determines the specific growth rate of a microorganism based on the substrate concentration, the half saturation constant, the inhibitory constant and the maximum growth rate achievable. However, for practical and experimental design purposes it is important to describe Haldane equation in terms of the initial concentration of substrate, since this information is required to know the proper amount of initial substrate to be used. For this reason, in the present paper we proposed to integrate the expression of yield factor and the definition of specific growth rate in a batch system into Haldane’s equation and to solve analytically the mathematical equations in order to obtain a final expression that correlates the maximum growth rate, the limiting nutrient concentration at which the specific growth is half its maximum value, the inhibitory constant, the initial concentration of substrate and the initial amount of biomass required in time. Accordingly, simulation and numerical studies are presented to analyze and discuss the importance of the obtained model

    Application of Box-Behnken design for treatment of tannery wastewater

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    This paper suggests a methodology for the adsorption of chromium from tannery wastewater as an ecological alternative to the contamination and toxic problems associated with this industry. The effect of mixtures of quarry stone and silica gel or activated carbon, particle size and pH were analyzed using a Box-Behnken design to evaluate and optimize the adsorption of chromium up to 88%.Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [LO1303 (MSMT-7778/2014)]; European Regional Development Fund under the project CEBIA-Tech [CZ.1.05/2.1.00/03.0089]; Lac Hong University, Dongnai, Vietna

    Estimation of psychrometric parameters of vapor water mixtures in air

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    In the present paper, a Visual Basic program was developed by describing the set of equations required to determine the value of seven different psychrometric properties (partial pressure of water vapor, absolute humidity, percentage humidity, relative humidity, dew point temperature, humid heat, humid volume or adiabatic saturation temperature) for mixtures of water vapor in air given the dry bulb temperature, the total atmospheric pressure and one additional parameter. Eight different cases are studied according to the corresponding input parameters. © 2015 Wiley Periodicals, Inc.European Regional Development Fund under the Project CEBIA-Tech [CZ.1.05/2.1.00/03.0089]; Tomas Bata University Internal Grant [IGA/CebiaTech/2015/046]; National Council of Science and Technology (CONACYT) in Mexic

    Application of the Box-Behnken model design to the optimization of process parameters in the convection-drying of Channa Striata fish

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    This study was aimed to identify the optimum parameters of the convention-drying Channa Striata fish using the Box-Behnken response surface methodology. The optimal experiments were designed with three factors including: density of loading Channa Striata fish, drying time and air speed. The results showed that drying temperature of 50, °C, air speed of 0.25, m/s, fish density of 6 pieces/tray (60, ×, 80, cm) and drying time of 196.82, min were determined to be the optimum parameters. Experiments were also made to verify the optimal conditions and evaluate the authenticity of the design model of drying fish. © Springer International Publishing AG 2018.Acknowledgements. This work was supported by the Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme project No. LO1303 (MSMT-7778/2014) and the European Regional Development Fund under the project CEBIA-Tech No. CZ.1.05/2.1.00/03.0089 and also by Lac Hong University in Vietnam
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