ABSTRACT
Objetivo: Cuando las resinas compuestas son expuestas a procesos de envejecimiento naturales en boca, como es el ciclaje térmico, pueden sufrir un deterioro en sus propiedades ópticas. El objetivo de este estudio fue evaluar la influencia del envejecimiento térmico sobre la estabilidad del color de dos resinas compuestas. Materiales y métodos: Se confeccionaron 120 pas- tillas de resinas compuestas, divididas en dos grupos: uno de resina Spectra Smart (n=60) y otro de resina Filtex Z350 XT (n=60). Estas muestras fueron sometidas a distintos regíme- nes de ciclaje térmico de 0, 10.000, 20.000 y 30.000 ciclos con temperaturas de entre 5 ºC +/- 2 ºC y 55 ºC +/- 2 °C. Los parámetros de color CIE L*a*b* de cada muestra se mi- dieron con un espectrofotómetro antes y después del proceso de envejecimiento. Las diferencias de color se calcularon me- diante la fórmula CIELAB (ΔE). Los datos fueron analizados estadísticamente usando la prueba no paramétrica de Kruskal Wallis y de U-Mann Whitney. Resultados: Los distintos regímenes de termociclado produjeron cambios de color estadísticamente significativos en ambos materiales. El material que tuvo menor estabilidad cromática fue Spectra Smart aunque sin diferencias estadísti- camente significativas. Conclusión: El envejecimiento térmico simulado a tres años afecta la estabilidad de color de las muestras, tanto de las resinas Spectra Smart, como de Filtex Z350 XT, sin alcanzar los valores que clínicamente determinarían la necesidad del reemplazo de las restauraciones (AU)
Aim: When composite resins are exposed to natural ag- ing processes in the mouth, such as the thermal cycling, they may suffer a deterioration in their optical properties. The aim of this study was to evaluate the influence of thermal aging on the color stability of two composite resins. Materials and methods: 120 composite resins tablets were made, divided into two groups: one of Spectra Smart res- in (n=60) and another of Filtex Z350 XT resin (n=60). These were subjected to different thermal cycle regimes of 0, 10,000, 20,000 and 30,000 cycles with temperature between 5 °C +/- 2 °C and 60 °C +/- 2 °C. The CIE L*a*b* color parameters of each sample were measured with a spectrophotometer before and after the aging process. Color differences were calculat- ed using the CIELAB formula (ΔE). The data were statisti- cally analyzed using the non-parametric Kruskal Wallis and U-Mann Whitney tests. Results: The different thermocycling regimes produce statistically significant color changes in both materials. The material that had the least chromatic stability was Spectra Smart, although without statistically significant differences. Conclusion: Simulated 3 year thermal aging affects the color stability of the samples, both Spectra Smart resins and Filtex Z350 XT, without reaching the values that would clini- cally determine the need to replace the restorations (AU)
Subject(s)
Thermodynamics , Composite Resins/chemistry , Hot Temperature/adverse effects , Spectrophotometry/methods , Materials Testing/methods , Data Interpretation, StatisticalABSTRACT
El objetivo de esta comunicación es describir y analizar el sistema BlueShaper para la preparación quirúrgica mecaniza- da de los conductos radiculares. El sistema dispone de un set básico de 4 limas: Z1, Z2, Z3 y Z4, con un D0 de 0,14 mm, 0,17 mm, 0,19 mm y 0,25 mm respectivamente y conicidad variable que oscila entre el 2 y 10 %. La lima Z1 posee una aleación Pink, que le confiere mayor resistencia a la torsión y una gran capacidad de corte. Las limas Z2, Z3 y Z4 presentan una aleación Blue que aumenta la resistencia a la fatiga cíclica e incrementa su flexibilidad. Para conductos radiculares más amplios se incluyen, además, las limas Z5, Z6 y Z7. La empresa comer- cializa conos de gutapercha BlueShaper que se corresponden con las limas Z3, Z4, Z5, Z6 y Z7. El sistema de limas mul- tialeación Blue Shaper podría considerarse como un nuevo aporte clínico para la preparación mecánica de los conductos radiculares (AU)
The aim of this communication was to describe and analyze the BlueShaper system for the mechanized surgical preparation of root canals. The system has a basic set of 4 files: Z1, Z2, Z3 and Z4, with 0.14 mm, 0.17 mm, 0.19 mm and 0.25 mm DO respective- ly, and variable conicity ranging between 2 and 10 %. Z1 file has a Pink alloy, which gives it greater resistance to torsion and great cutting capacity. The Z2, Z3 and Z4 files feature a Blue alloy that increases resistance to cyclic fatigue and increases their flexibility. For larger root canals, the Z5, Z6 and Z7 files are also included. The company supplies specific BlueShaper Ìs gutta-percha cones for Z3, Z4, Z5, Z6 and Z7 files. The BlueShaper multialloy file system could be consid- ered as a new clinical contribution for the mechanical prepa- ration of root canals (AU)
Subject(s)
Root Canal Preparation/instrumentation , Dental Alloys , Dental Instruments , Rotation , Thermodynamics , Torsion, MechanicalABSTRACT
Se ha confirmado que la composición química de Similimum en personas sanas es la misma que la de individuos enfermos. Este es el hallazgo más importante en apoyo de una interpretación termodinámica de la homeopatía y se basa en la curación de pacientes con similimum con respecto al equilibrio químico en personas enfermas. La composición química de similimum no es necesaria para un tratamiento en la homeopatía. Todo lo que se requiere es la misma composición química entre las dos moléculas objetivo. Conocer la composición química de las moléculas que causan enfermedades solo es relevante en el caso de buscar un compuesto que pueda actuar como un similimum
It has been confirmed that the chemical composition of Similimum in healthy people is the same as that in diseased individuals. This is the most important finding in support of a thermodynamic interpretation of homeopathy and is based on the healing of patients with Similimum regarding the chemical equilibrium in diseased people. The chemical composition of Simillimum is not required for a treatment in homeopathy. All that is required is the same chemical composition between the two target molecules. Knowing the chemical composition of disease-causing molecules is only relevant in the case of searching for a compound that could act as a Simillimum
Subject(s)
Humans , Male , Female , Thermodynamics , Simillimum , HomeopathyABSTRACT
The aim of this study was to investigate the influence of the quantity and positioning of feldspathic ceramic specimens inside the furnace on their flexural strength and translucency. The tested hypotheses were that the arrangement of specimens in the furnance would not influence 1) the translucency or 2) the biaxial strength of the porcelain. Methods: Ninety porcelain specimens were made (1.2 mm thickness and 13.5 mm diameter) and assigned into two main groups (n=15): G1 group - 15 firing cycles containing only one specimen each, always at the center of the refractory; and G5 group - 15 firing cycles containing five specimen each, where one specimen was at the center of the refractory and four specimens positioned equidistantly on the periphery. The translucency test was performed using a spectrophotometer, followed by the flexural strength test, according to ISO 6872:2015. T-student test was performed for both the mechanical and optical obtained data. Results: The flexural strength of the porcelain was not affected by the positioning (center x periphery) of the specimens inside the furnace (p =0.08), but the translucency was affected (periphery > center; p =0.009). Regarding to the number of feldspathic ceramic specimens, the biaxial flexural strength was affected (p =0.025), as well as the translucency (p <0.05). Conclusion: A higher quantity of feldspathic ceramic specimens for each firing cycle decreased its biaxial flexural strength and translucency. Also, specimens positioned at the center of the refractory became less translucent than those positioned at the periphery.
Subject(s)
Humans , Thermodynamics , Dental Porcelain/chemistry , Absorption, Physicochemical , Flexural Strength , Light , Spectrophotometry , Temperature , Materials Testing , Microscopy, Electron, Scanning , Fractographic AnalysisABSTRACT
Este artículo cubre los conceptos básicos de un nuevo modelo de homeopatía que se basa en la termodinámica química. La equivalencia entre el compuesto que causa la enfermedad en una persona saludable y el compuesto que causa la enfermedad en una persona enferma, lo que llevó a esta interpretación del nuevo modelo de homeopatía, está bien considerado. Se han considerado el mecanismo de curación, la Ley de los Similares y la Ley de los Infinitesimales. Este artículo también analiza los conceptos básicos del mecanismo de dilución y su influencia en la concentración final de moléculas de remedio en soluciones homeopáticas. El número máximo de pasos sucesivos que impliquen una molienda vigorosa y se consideró la dilución donde todavía es posible la existencia de una concentración terapéutica.
Tis article covers the basics of a new model of homeopathy that is grounded in chemical thermodynamics. Te equivalence between the disease-causing compound in a heathy person and the disease-causing compound in an ill person, which led to this interpretation of the new model of homeopathy, is well considered. Te mechanism of curing, the Law of Similars, and the Law of Infinitesimals were considered. Tis article also discusses the basics of the dilution mechanism and its influence on the final concentration of remedy molecules in homeopathic solutions. Te maximum number of succession steps involving vigorous grinding and dilution where the existence of a therapeutic concentration is still possible was considered
Subject(s)
Humans , Thermodynamics , /methods , Small Doses , Principle of Similarity/methods , Potency , Dilution/methods , Chemical Phenomena , Homeopathy/methodsABSTRACT
Constraint-based genome-scale metabolic network models (genome-scale metabolic models, GEMs) have been widely used to predict metabolic phenotypes. In addition to stoichiometric constraints, other constraints such as enzyme availability and thermodynamic feasibility may also limit the cellular phenotype solution space. Recently, extended GEM models considering either enzymatic or thermodynamic constraints have been developed to improve model prediction accuracy. This review summarizes the recent progresses on metabolic models with multiple constraints (MCGEMs). We presented the construction methods and various applications of MCGEMs including the simulation of gene knockout, prediction of biologically feasible pathways and identification of bottleneck steps. By integrating multiple constraints in a consistent modeling framework, MCGEMs can predict the metabolic bottlenecks and key controlling and modification targets for pathway optimization more precisely, and thus may provide more reliable design results to guide metabolic engineering of industrially important microorganisms.
Subject(s)
Genome , Metabolic Engineering , Metabolic Networks and Pathways/genetics , Models, Biological , ThermodynamicsABSTRACT
Abstract This study describes the use of bentonite in suspension for the caffeine adsorption (pollutant of emerging concern) by taking different conditions of the pH, adsorbent mass, adsorbent calcination temperature and interferents into account. The results were compared with those obtained using bentonite immobilized in alginate beads. The acid medium has a greater efficiency for the caffeine adsorption and the adsorbent calcination temperature exerts, due to structural changes. Caffeine removal higher than 90% was obtained at optimized conditions. The Langmuir model indicated a better fit of the data and the adsorption capacity of caffeine onto bentonite. The bentonite immobilized led to a slower adsorption process in relation to the suspended.
Subject(s)
Water Pollutants, Chemical/isolation & purification , Bentonite/chemistry , Caffeine/chemistry , Thermodynamics , Caffeine/adverse effects , Adsorption , Environmental Pollutants/isolation & purification , Hot Temperature , Hydrogen-Ion Concentration , Models, TheoreticalABSTRACT
OBJECTIVE@#To seek potential Chinese herbal medicine (CHM) for the treatment of coronavirus disease 2019 (COVID-19) through the molecular docking of the medicine with SARS-CoV-2 3CL hydrolytic enzyme and the angiotensin converting enzyme II(ACE2) as receptors, using computer virtual screening technique, so as to provide a basis for combination forecasting.@*METHODS@#The molecular docking of CHM with the SARS-Cov-2 3CL hydrolase and the ACE2 converting enzyme, which were taken as the targets, was achieved by the Autodock Vina software. The CHM monomers acting on 3CLpro and ACE2 receptors were retrieved from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform, the active ingredients were selected, and the key CHMs and compounds were speculated. Based on the perspective of network pharmacology, the chemical-target network was constructed, and the functional enrichment analysis of gene ontology and the pathway enrichment analysis of Kyoto encyclopedia of genes and genomes were carried out by DAVID to speculate about the mechanism of action of the core drug pairs.@*RESULTS@#There are 6 small molecule compounds that have the optimal binding energy with the two target proteins. Among 238 potential anti-COVID-19 herbs screened in total, 16 kinds of CHM containing the most active ingredients, and 5 candidate anti-COVID-19 herbs that had been used in high frequency, as well as a core drug pair, namely, Forsythiae Fructus-Lonicerae Japonicae Flos were selected.@*CONCLUSION@#The core drug pair of Forsythiae Fructus-Lonicerae Japonicae Flos containing multiple components and targets is easy to combine with 3CLpro and ACE2, and exerts an anti-COVID-19 pneumonia effect through multi-component and multi-target, and plays the role of anti-COVID-19 pneumonia in multi-pathway.
Subject(s)
Humans , Betacoronavirus , Metabolism , Computer Simulation , Coronavirus Infections , Drug Therapy , Drugs, Chinese Herbal , Therapeutic Uses , Gene Ontology , Molecular Docking Simulation , Pandemics , Peptidyl-Dipeptidase A , Metabolism , Pneumonia, Viral , Drug Therapy , ThermodynamicsABSTRACT
RESUMEN Objetivo. Establecer mediante experimentos por lote la capacidad de remoción, la cinética y termodinámica de adsorción del carbón activado preparado a partir de la cáscara de yuca (Manihot esculenta) en la remoción del colorante azul directo 86. Materiales y métodos. La metodología experimental consistió inicialmente en la preparación del carbón activado por activación química de la cáscara de yuca con H3PO4 y su posterior calcinación a 530°C. En la caracterización se determinaron las propiedades de textura mediante el índice de yodo e índice de azul de metileno, se cuantificaron los grupos funcionales orgánicos ácidos y básicos con el método Boehm, y se realizó el análisis próximo siguiendo las normas ASTM D-2867-70, ASTM D2866 y ASTM D2866-94. En el estudio por lote, el efecto de varios parámetros sobre la capacidad de adsorción fueron evaluados: el pH (2, 4, 8 y 10), la temperatura (25, 30 y 40°C) y la concentración inicial de colorante (20, 40, 60, 80 y 100 mg/L). Tanto las características fisicoquímicas como los ensayos de adsorción del carbón activado preparado a partir de la cáscara de yuca (CAY) fueron comparadas con otro de marca comercial (CAM). Resultados. Los resultados de la caracterización indican que ambos carbones tienen una química de superfície heterogénea, de naturaleza ácida para el CAY y básica para el CAM. La máxima capacidad obtenida fue 6.1 mg/g para el CAY y de 3.7 mg/g para el CAM. Los cálculos termodinámicos indican que la remoción es espontánea y para ambos carbones la cinética se ajusta al modelo de pseudo segundo orden. Conclusiones. El carbón activado obtenido a partir de la cáscara de yuca puede considerarse un adsorbente eficiente en la remoción de colorantes.
ABSTRACT Objective. To establish by means of experimenting by batch the capacity of removal, the kinetics and adsorption thermodynamics of activated carbon prepared from manioc husk (Manihot esculenta) in the removal of direct blue 86 dye. Materials and methods. Firstly, the experimental methodology worked on the preparation of activated carbon by chemical activation of manioc husk with H3PO4 calcined at 530°C. In the characterization the texture properties were determined by means of the blue methylene and iodine indices, the basic and acidic functional groups were quantified by the Boehm method, and the proximate analyses were done following the norms ASTM D2867-70, ASTM D2866 and ASTM D2866-94. During the batch studies, the effect of several parameters over the adsorption capacity was evaluated: pH (2, 4, 8 and 10), temperature (25, 30 and 40°C) and initial concentration of the dye (20, 40, 60, 80 and 100 mg/L). Both physicochemical and adsorption characteristics of the activated carbon from manioc husk (CAY) were compared against those of a commercial brand (CAM). Results. The results of characterization showed that both carbons have a chemistry heterogeneous surface, acidic for CAY and basic for CAM. The maximum capacity obtained was 6.1 mg/g for CAY and 3.7 mg/g for CAM. The thermodynamic calculations showed that the removal was spontaneous. The kinetics for both carbon samples fits a pseudo second-order model. Conclusions. The activated carbon obtained from the manioc husk can be considered an efficient adsorbent for the removal of dyes.
Subject(s)
Thermodynamics , Kinetics , Manihot , CharcoalABSTRACT
Abstract The effects of gamma radiation (0, 1, 2 and 3 kGy) were used to evaluate the stability and thermal degradation kinetics of anthocyanins, as well as the stability of total phenolic compounds (TPC) and antioxidant activity at different temperatures (4, 25, 35 and 45 °C) during the storage (0, 30, 60, 90 and 120 days) of black rice flour. This flour can be used as ingredient for gluten-free cereal products with higher nutritional value. For this it is necessary to preserve the anthocyanin content during thermal processing and shelf-life periods. At time 0, the dose of 3 kGy provided all of the most available bioactive compounds, raising their antioxidant potential, except for TPC. During the storage at different temperatures up to 120 days, gradual losses occurred in all the analysed parameters. Regarding the total anthocyanin content and TPC, the sample irradiated with a 1 kGy dose remained most stable. The analysis of kinetic data indicated a first-order reaction for the degradation of anthocyanins. The combination of irradiation with different temperatures may improve the shelf-life of black rice flour.
Subject(s)
Radiation , Oryza , Thermodynamics , Phytochemicals , Anthocyanins/chemistryABSTRACT
Genome-scale metabolic network models have been successfully applied to guide metabolic engineering. However, the conventional flux balance analysis only considers stoichiometry and reaction direction constraints, and the simulation results cannot accurately describe certain phenomena such as overflow metabolism and diauxie growth on two substrates. Recently, researchers proposed new constraint-based methods to simulate the cellular behavior under different conditions more precisely by introducing new constraints such as limited enzyme content and thermodynamics feasibility. Here we review several enzyme-constrained models, giving a comprehensive introduction on the biological basis and mathematical representation for the enzyme constraint, the optimization function, the impact on the calculated flux distribution and their application in identification of metabolic engineering targets. The main problems in these existing methods and the perspectives on this emerging research field are also discussed. By introducing new constraints, metabolic network models can simulate and predict cellular behavior under various environmental and genetic perturbations more accurately, and thus can provide more reliable guidance to strain engineering.
Subject(s)
Enzymes , Metabolism , Genome , Genetics , Metabolic Engineering , Metabolic Networks and Pathways , Genetics , Models, Biological , ThermodynamicsABSTRACT
Small molecules with physiological or pharmacological activities need to interact with biological macromolecules in order to function in the body. As the protein with the highest proportion of plasma protein,serum albumin is the main protein binding to various endogenous or exogenous small molecules. Serum albumin interacts with small molecules in a reversible non-covalent manner and transports small molecules to target sites. Bovine serum albumin( BSA) is an ideal target protein for drug research because of its low cost and high homology with human serum albumin. The research on the interaction between drugs and BSA has become a hotspot in the fields of pharmacy,medicine,biology and chemistry. In this research,molecular docking method was used to study the interaction between three small ginsenosides with high pharmacological value( Rg_1,Rb_1,Ro) and bovine serum albumin( BSA),and the binding mode information of three ginsenosides interacting with BSA was obtained. The results of molecular docking showed that ginsenosides and amino acid residues in the active pocket of proteins could be combined by hydrophobic action,hydrogen bonding and electrostatic action. The interaction between small ginsenosides and bovine serum albumin is not the only form,and their interaction has many forms of force. The interaction between these molecules and various weak forces is the key factor for the stability of the complex. The results of this study can provide the structural information of computer simulation for the determination of the interaction patterns between active components and proteins of ginseng.
Subject(s)
Animals , Cattle , Binding Sites , Computer Simulation , Ginsenosides , Chemistry , Molecular Docking Simulation , Protein Binding , Serum Albumin, Bovine , Chemistry , Spectrometry, Fluorescence , ThermodynamicsABSTRACT
Abstract Data Centers are growing steadily worldwide, and they are expected to continue growing up to 53% in 2020. Energy efficiency, in high power consumption, is a key venue. There are methodologies to measure this efficiency, one example is using the PUE (Power Usage Effectiveness) index. In this paper is proposed a new index for measuring efficiency at the design stage, the EUED (Energy Usage Effectiveness Design). This index allows to evaluate systems using "free cooling" and adiabatic system. A comparison is performed considering the equipment in the worst situation. The thermodynamics parameter enthalpy is used to calculate the results. This new methodology allows to determine differences between the cities of São Paulo and Curitiba (1.21%) and between Rio de Janeiro and Curitiba (10.61%). The values for the EUED index were 1.245 kW/kW for Curitiba, 1.260 kW/kW for São Paulo and 1.377 kW/kW for Rio de Janeiro, respectively, reaching a difference of 16.86% for Curitiba, 16.19% for São Paulo and 10.31% for Rio de Janeiro in relation to PUE COA (Power Usage Effectiveness Constant Outdoor Air). The advantage of the EUED is that it works with the 8,760 hours in the design phase, using psychometric elements to determine when to use free cooling and evaporative system, and more importantly varying the COP according to environmental characteristics.
Subject(s)
Efficiency , Energy Consumption , Hot Temperature , ThermodynamicsABSTRACT
RESUMO O presente artigo tem como objetivo abordar o conceito de máquina e a consequente apropriação do mesmo nas discussões sobre a subjetividade. É um estudo teórico na interface entre psicologia, filosofia, física e biologia. Nesse sentido, ele se inicia apresentando que, na modernidade, a analogia à máquina foi estendida à compreensão do universo como sendo um relógio preciso e geometricamente previsível em seu funcionar. E se, até o século XVIII, a vida, o corpo e o cosmos foram significados, pela ciência emergente, como uma máquina mecânica (de movimento calculável em sua previsibilidade), no século XIX estes passaram igualmente a serem compreendidos como uma máquina térmica, com seus desdobramentos na física da termodinâmica e na cibernética. No final do século XX, a partir dos trabalhos dos biólogos Francisco Varela e Humberto Maturana, o conceito de máquina autopoiética ganhou relevância nos estudos sobre a vida e sobre a cognição, sendo este apropriado por Félix Guattari no desenvolvimento de seu conceito de produção de subjetividade e suas problematizações em torno dos processos de subjetivação. Assim, o conceito de máquina saiu das limitações de uma leitura mecânica e termodinâmica da realidade, para uma abordagem existencial, processual e inventiva da subjetividade.
RESUMEN El presente artículo tiene como objetivo abordar el concepto de máquina y la consiguiente apropiación del mismo en las discusiones sobre la subjetividad. Es un estudio teórico en la interfaz entre Psicología, Filosofía, Física y Biología. En ese sentido, se inicia presentando que, en la modernidad, la analogía a la máquina se extendió a la comprensión del universo como un reloj preciso y geométricamente previsible en su funcionamiento. Y si, hasta el siglo XVIII, la vida, el cuerpo y el cosmos fueron significados, por la ciencia emergente, como una máquina mecánica (de movimiento calculable en su previsibilidad), en el siglo XIX estos pasaron igualmente a ser comprendidos como una máquina térmica, con sus desdoblamientos en la física de la termodinámica y en la cibernética. A finales del siglo XX, a partir de losestudios de los biólogos Francisco Varela y Humberto Maturana, el concepto de máquina autopoiética ganó relevancia en los estudios sobre la vida y sobre la cognición, siendo éste apropiado por Félix Guattari en el desarrollo de su concepto de producción de subjetividad y sus problemasen torno a los procesos de subjetivación. Así, el concepto de máquina salió de las limitaciones de una lectura mecánica y termodinámica de la realidad, hacia un enfoque existencial, procesal e inventivo de la subjetividad.
ABSTRACT This article aims to address the concept of machine and its consequent appropriation in the discussions on subjectivity. It is a theoretical study at the interface among Psychology, Philosophy, Physics and Biology. In this sense, it starts showing that in the modernity, the analogy to the machine was extended to the understanding of the universe as a precise and geometrically predictable functioning clock. And if, until the eighteenth century, life, body and cosmos were signified by the emerging science as a mechanical machine (of calculable motion in its predictability), in the nineteenth century they also came to be understood as a thermal machine, with its developments in the thermodynamics physics and cybernetics. In the late twentieth century, the concept of autopoietic machine gained relevance in the studies of life and cognition, based on the works of the biologists Francisco Varela and Humberto Maturana, which is appropriated by Félix Guattari for the development of his concept of the production of subjectivity and its problematizations around the subjectivation processes. Thus, the concept of machine has gone beyond the limitations of a mechanical and thermodynamics reading of reality, to an existential, procedural and inventive approach of the subjectivity.
Subject(s)
History, 18th Century , History, 19th Century , History, 20th Century , History, 21st Century , Artificial Intelligence , Cybernetics , Virtual Reality , Physics , Thermodynamics , Mechanics , Machine Learning , MotionABSTRACT
A thermodynamic paradigm for studying disease vectors habitats & life cycles using NASAs remote sensing data is being proposed. NASAs current and planned satellite missions provide measurements of the critical environmental measures environmental state functions important to vector & disease life cycles such as precipitation, soil moisture, temperature, vapor pressure deficits, wet/dry edges, and solar radiation. Satellite data provide landscape scale process functions represented by land use/cover mapping and actual measurements of ecological functions/structure: canopy cover, species, phenology, and aquatic plant coverage. These measurements are taken in a spatial context and provide a time series of data to track changes in time. Global public health is entering a new informational age through the use of spatial models of disease vector/host ecologies driven by the use of remotely sensed data to measure environmental and structural factors critical in determining disease vector habitats, distributions, life cycles, and host interactions. The vector habitat microclimates can be quantified in terms of the surface energy budget measured by satellites. The epidemiological equations (processes) can be adapted and modified to explicitly incorporate environmental factors and interfaces required by a specific disease and its vector/host cycle. Remote sensing can be used to measure or evaluate or estimate both environment (state functions) and interface (process functions). It is critical that the products of remote sensing must be expressed in a way they can be integrated directly into the epidemiological equations.
Um paradigma termodinâmico para estudar os habitats e ciclos de vida dos vetores de doenças utilizando dados de sensoriamento remoto da NASA está sendo proposto. As missões atuais e planejadas para os satélites da NASA fornecem medições das funções críticas ambientais e funções do estado ambiental, importantes para os ciclos de vida de vetores e doenças, como precipitação, umidade do solo, temperatura, déficits de pressão do vapor, bordas úmidas/secas e radiação solar. Os dados de satélite fornecem as funções dos processos na escala da paisagem, representada pelo mapeamento do uso/cobertura da terra e medições reais das funções/estruturas ecológicas: cobertura do dossel, espécies, fenologia e cobertura de plantas aquáticas. Essas medições são feitas em um contexto espacial e fornecem uma série temporal de dados para rastrear dinâmica das mudanças. A saúde pública global está entrando em uma nova era informacional através do uso de modelos espaciais para vetores/hospedeiros de doenças, impulsionados pelo uso de dados de sensoriamento remoto, para medir fatores ambientais e estruturais críticos na determinação de habitats de vetores de doenças, distribuições, ciclos de vida e interações com o hospedeiro. Os microclimas dos habitats vetoriais podem ser quantificados em termos do orçamento de energia superficial, medidos por satélites. As equações epidemiológicas (processos) podem ser adaptadas e modificadas para incorporar explicitamente fatores e interfaces ambientais requeridos por uma doença específica e o ciclo do seu vetor/hospedeiro. O sensoriamento remoto pode ser usado para medir ou avaliar, ou mesmo estimar tanto o ambiente (funções do seu estado) quanto a interface (funções de seus processos). É fundamental que os produtos de sensoriamento remoto sejam expressos de forma a integrá-los diretamente às equações epidemiológicas.
Subject(s)
Epidemiological Monitoring , Geographic Information Systems , Remote Sensing Technology , Thermodynamics , Spacecraft , United States , United States National Aeronautics and Space AdministrationABSTRACT
Dehydrated garlic is an importance spice in pre-cooked and processed food products, but studies of the drying variables of this product are scarce. Thus, this work aimed to model and study the kinetics of garlic drying at three different temperatures (40, 50 and 60 °C) and analyze the thermodynamic parameters during the process. The drying was analyzed using pre-established mathematical models for agricultural products and equations that describe the thermodynamics of product dehydration. The best mathematical adjustment for all drying temperatures was the Midilli equation. The moisture ratio was seen to decrease during the process for all situations. The effective diffusivity increased with increasing temperature. The enthalpy change was positive during the process and decreased with increasing temperature. The study entropy was negative, indicating a non-spontaneous reaction. In addition, the Gibbs free energy increased with increasing drying temperature. The thermodynamic standards were satisfactory and correctly described the moisture loss by the garlic samples.
O alho desidratado é um tempero de suma importância em produtos pré-cozidos e processados, no entanto, o estudo das variáveis de secagem desse produto é escasso. Diante disso, objetivou-se com esse trabalho estudar a cinética e a modelagem da secagem de alho, em três temperaturas distintas (40, 50 e 60 °C), e analisar os parâmetros termodinâmicos durante o processo. O estudo da secagem foi feito por meio de modelos matemáticos pré-estabelecidos para produtos agrícolas e por equações que descrevem a termodinâmica da desidratação de produtos. O melhor ajuste matemático foi à equação de Midilli para todas as temperaturas de secagem. A razão de umidade apresentou-se decrescente durante o processo para todas as situações. A difusividade efetiva aumentou com o aumento da temperatura. A variação de entalpia apresentou-se positiva durante o processo de secagem e diminui com o aumento da temperatura. A entropia estudada foi negativa, indicando uma reação não-espontânea. E a energia livre de Gibbs aumentou com a elevação da temperatura de secagem. Os padrões termodinâmicos foram satisfatórios e descreveram como ocorreu a perda de umidade pelas amostras de alho.
Subject(s)
Thermodynamics , Kinetics , Food Preservation , GarlicABSTRACT
Entero virus 71 (EV71) causes hand, foot, and mouth disease (HFMD) and occasionally leads to severe neurological complications and even death. Scavenger receptor class B member 2 (SCARB2) is a functional receptor for EV71, that mediates viral attachment, internalization, and uncoating. However, the exact binding site of EV71 on SCARB2 is unknown. In this study, we generated a monoclonal antibody (mAb) that binds to human but not mouse SCARB2. It is named JL2, and it can effectively inhibit EV71 infection of target cells. Using a set of chimeras of human and mouse SCARB2, we identified that the region containing residues 77-113 of human SCARB2 contributes significantly to JL2 binding. The structure of the SCARB2-JL2 complex revealed that JL2 binds to the apical region of SCARB2 involving α-helices 2, 5, and 14. Our results provide new insights into the potential binding sites for EV71 on SCARB2 and the molecular mechanism of EV71 entry.
Subject(s)
Animals , Humans , Mice , Amino Acid Sequence , Antibodies, Monoclonal , Chemistry , Genetics , Metabolism , Binding Sites , Cell Line , Crystallography, X-Ray , Enterovirus A, Human , Genetics , Allergy and Immunology , Fibroblasts , Virology , Gene Expression , HEK293 Cells , Immunoglobulin Fab Fragments , Chemistry , Genetics , Metabolism , Lysosomal Membrane Proteins , Chemistry , Genetics , Allergy and Immunology , Models, Molecular , Protein Binding , Protein Conformation, alpha-Helical , Protein Conformation, beta-Strand , Protein Interaction Domains and Motifs , Receptors, Scavenger , Chemistry , Genetics , Allergy and Immunology , Receptors, Virus , Chemistry , Genetics , Allergy and Immunology , Recombinant Fusion Proteins , Chemistry , Genetics , Allergy and Immunology , Sequence Alignment , Sequence Homology, Amino Acid , Sf9 Cells , Spodoptera , ThermodynamicsABSTRACT
ABSTRACT The interaction between 6-shogaol, a pharmacologically active ginger constituent, and human serum albumin (HSA), the main in vivo drug transporter, was investigated using isothermal titration calorimetry (ITC). The value of the binding constant, Ka (5.02 ± 1.37 × 104 M−1) obtained for the 6-shogaol-HSA system suggested intermediate affinity. Analysis of the ITC data revealed feasibility of the binding reaction due to favorable enthalpy and entropy changes. The values of the thermodynamic parameters suggested involvement of van der Waals forces, hydrogen bonds and hydrophobic interactions in the 6-shogaol-HSA complex formation.
Subject(s)
Thermodynamics , Zingiber officinale/anatomy & histology , Biological Products/pharmacokinetics , Calorimetry , Serum Albumin/analysisABSTRACT
ABC transporters form the largest of all transporter families, and their structural study has made tremendous progress over recent years. However, despite such advances, the precise mechanisms that determine the energy-coupling between ATP hydrolysis and the conformational changes following substrate binding remain to be elucidated. Here, we present our thermodynamic analysis for both ABC importers and exporters, and introduce the two new concepts of differential-binding energy and elastic conformational energy into the discussion. We hope that the structural analysis of ABC transporters will henceforth take thermodynamic aspects of transport mechanisms into account as well.