Development of a Critically Evaluated Thermodynamic Databse for the Systems Containing Alkaline-Earth Oxides

Dans un système thermodynamique multicomposant, les relations de phases entre les constituants sont généralement très complexes. En particulier, les systèmes à base d’oxydes sont souvent très difficiles à étudier en raison des températures très élevées et de l'action corrosive des laitiers. A cause de ces difficultés, de grandes incohérences et dispersions sont souvent observées parmi les données expérimentales disponibles dans la littérature. Afin d'étudier et de comprendre de manière efficace les relations de phases complexes, il est très utile de développer des banques de données thermodynamiques contenant les paramètres optimisés d’un modèle d’énergie libre de Gibbs, permettant de dériver les propriétés thermodynamiques de toutes les phases en fonction de la température et de la composition. Dans une optimisation thermodynamique, les paramètres ajustables du modèle d’énergie libre de Gibbs sont calculés en utilisant simultanément toutes les données thermodynamiques et d'équilibres de phases disponibles afin d'obtenir un ensemble d'équations en fonction de la température et de la composition. Les données thermodynamiques, telles que les activités, peuvent aider à évaluer les diagrammes de phases, et les informations sur les équilibres de phases peuvent être utilisées pour déduire les propriétés thermodynamiques. Ainsi, il est souvent possible de résoudre les divergences observées entre les données expérimentales disponibles. A partir des équations du modèle, toutes les propriétés thermodynamiques et les diagrammes de phases peuvent être calculés rétrospectivement. Il est également possible d’effectuer des interpolations et extrapolations de manière cohérente d’un point de vue thermodynamique. Les données sont ainsi rendues auto-cohérentes et, conformément aux principes thermodynamiques, les données expérimentales disponibles sont reproduites par un petit jeu de paramètres du modèle; ce qui est idéal pour le stockage informatique. iv Dans le cadre d'un vaste projet de recherche au Centre de Recherche en Calcul Thermochimique (CRCT) au sein de l'Ecole Polytechnique de Montréal, nous avons développé une banque de données thermodynamiques pour les systèmes d'oxydes multicomposants. Cette thèse consiste en l'ajout des composants SrO et BaO à la banque de données multicomposante existant déjà pour le système SiO2-B2O3-Al2O3-CaO-MgO. Au fil des années, en collaboration avec de nombreuses compagnies industrielles, une banque de données thermodynamiques a été développée pour le système SiO2-B2O3-Al2O3-CaO-MgO de manière tout à fait satisfaisante. L'objectif du présent travail est d'améliorer l'applicabilité de cette banque de données en y ajoutant les nouveaux composants SrO et BaO. Les banques de données élaborées dans ce travail seront d'une importance particulière pour les industries des verres et de l’acier. Dans le système SiO2-B2O3-Al2O3-CaO-MgO-BaO-SrO, il y a 11 sous-systèmes binaires et 25 sous-systèmes ternaires contenant soit BaO, soit SrO ou bien les deux à la fois. Pour la plupart de ces systèmes binaires, et pour aucun de ces systèmes ternaires, des « optimisations » thermodynamiques sont déjà disponibles dans la littérature. Dans cette thèse, nous présentons l'évaluation et l'optimisation thermodynamique de 11 sous-systèmes binaires, 17 sous-systèmes ternaires et 5 sous-systèmes quaternaires contenant BaO et/ou SrO issus du système SiO2-B2O3-Al2O3-CaO-MgO-BaO-SrO. Toutes ces optimisations thermodynamiques ont été effectuées en se basant sur les données expérimentales disponibles dans la littérature, à l’exception du système SrO-B2O3-SiO2 qui a été optimisé à partir de données expérimentales obtenues dans le présent travail en conjonction avec les données issues de la littérature. v Dans cette thèse, tous les calculs ont été réalisés à l’aide du logiciel FactSageTM de calcul d’équilibres thermodynamiques. Le Modèle Quasichimique Modifié (MQM) prenant en compte l’ordre à courte distance a été utilisé pour la phase liquide. Tous les systèmes binaires ont été évalués de manière critique et optimisés à partir des données thermodynamiques et d'équilibre de phases disponibles dans la littérature. Les paramètres du modèle obtenus ont été utilisés pour représenter les énergies de Gibbs de toutes les phases en fonction de la température et de la composition. Les paramètres binaires du modèle ont été utilisés pour estimer les propriétés thermodynamiques des phases dans les systèmes ternaires. Des modèles « géométriques » appropriés ont été utilisés pour ces estimations. Les diagrammes de phases ternaires ont été calculés et comparés avec les données expérimentales disponibles. Des paramètres d'interaction ternaires ont également été ajoutés lorsque cela était nécessaire. La première partie de cette thèse est consacrée à une revue exhaustive de la littérature sur le thème de la modélisation thermodynamique et des techniques expérimentales de détermination de diagrammes de phases. Les chapitres suivants comprennent la revue de la littérature ainsi que les optimisations thermodynamiques des différents systèmes. La dernière partie de cette thèse est consacrée à la présentation du travail expérimental (trempe et EPMA) effectué pour le système SrO-B2O3-SiO2. ---------- In a thermodynamic system which contains several elements, the phase relationships among the components are usually very complex. Especially, systems containing oxides are generally very difficult to investigate owing to the very high experimental temperatures and corrosive action of slags. Due to such difficulties, large inconsistencies are often observed among the available experimental data. In order to investigate and understand the complex phase relationships effectively, it is very useful to develop thermodynamic databases containing optimized model parameters giving the thermodynamic properties of all phases as functions of temperature and composition. In a thermodynamic optimization, adjustable model parameters are calculated using, simultaneously, all available thermodynamic and phase-equilibrium data in order to obtain one set of model equations as functions of temperature and composition. Thermodynamic data, such as activities, can aid in the evaluation of the phase diagrams, and information on phase equilibria can be used to deduce thermodynamic properties. Thus, it is frequently possible to resolve discrepancies in the available data. From the model equations, all the thermodynamic properties and phase diagrams can be back-calculated, and interpolations and extrapolations can be made in a thermodynamically correct manner. The data are thereby rendered self-consistent and consistent with thermodynamic principles, and the available data are distilled into a small set of model parameters, ideal for computer storage. As part of a broader research project at the Centre de Recherche en Calcul Thermochimique (CRCT), Ecole Polytechnique to develop a thermodynamic database for multicomponent oxide systems, this thesis deals with the addition of components SrO and BaO to the existing vii multicomponent database of the SiO2-B2O3-Al2O3-CaO-MgO system. Over the years, in collaboration with many industrial companies, a thermodynamic database for the SiO2-B2O3-Al2O3-CaO-MgO system has been built quite satisfactorily. The aim of the present work was to improve the applicability of this five component database by adding SrO and BaO to it. The databases prepared in this work will be of special importance to the glass and steel industries. In the SiO2-B2O3-Al2O3-CaO-MgO-BaO-SrO system there are 11 binary systems and 25 ternary systems which contain either BaO or SrO or both. For most of these binary systems, and for none of these ternary systems, is there a previous thermodynamic optimization available in the literature. In this thesis, thermodynamic evaluation and optimization for the 11 binary, 17 ternary and 5 quaternary BaO- and SrO- containing systems in the SiO2-B2O3-Al2O3-CaO-MgO-BaO-SrO system is presented. All these thermodynamic optimizations were performed based on the experimental data available in the literature, except for the SrO-B2O3-SiO2 system. This latter system was optimized on the basis of a few experimental data points generated in the present work together with the data from the literature. In the present work, all the calculations were performed using the FactSageTM thermochemical software. The Modified Quasichemical Model (MQM), which is capable of taking short-range ordering into account, was used for the liquid phase. All the binary systems were critically evaluated and optimized using available phase equilibrium and thermodynamic data. The model parameters obtained as a result of this simultaneous optimization were used to represent the Gibbs energies of all phases as functions of temperature and composition. Optimized binary viii model parameters were used to estimate the thermodynamic properties of phases in the ternary systems. Proper “geometric” models were used for these estimations. Ternary phase diagram were calculated and compared with available experimental data. Wherever required, ternary interaction parameters were also added. The first part of this thesis comprises a general literature review on the subject of thermodynamic modeling and experimental techniques for phase diagram determination. The next chapters include the literature review and the thermodynamic optimizations of the various systems. The last part of the thesis is the presentation of experiments performed in the present work, by quenching and EPMA, in the SrO-B2O3-SiO2 system. The experiments were designed to generate the maximum amount of information with the minimum number of experiments using the thermodynamic optimization, based only on the data available in the literature, as a guide. These newly-obtained data improved the (preceding) thermodynamic optimization, based on the experimental data in the literature, of this ternary system

Development of a critically evaluated thermodynamic database for magnesium alloys

CALPHAD -- Thermodynamic modeling -- Modified Quasichemical Model (MQM) -- Thermodynamic modeling of solids -- Extension to ternary system from binary systems -- Predictions using only binary parameters -- Thermodynamic assessment of the Ce-Si, Y-Si, Mg-Ce-Si and Mg-Y-Si systems -- Binary systems -- Ternary systems -- Thermodynamic assessment of the Si-Zn, Mn-Si, Mg-Si-Zn and Mg-Mn-Si systems -- Thermodynamic assessment of the Al-Mn and Mg-Al-Mn systems

In silico investigation of antioxidant interaction and effect of probiotic fermentation on antioxidant profiling of pearl millet-based rabadi beverage

Pearl millet-based food products can be used for weight control and minimize the possibility of chronic diseases. They have protein, minerals, fat, phenolic compounds, and a diminutive glycemic index. Moreover, Probiotic fermentation can bring specific additional benefits in addition to nutritional improvements. In silico analysis of the chemical-protein interaction of tannic acid and ascorbic acid of pearl millet was undertaken. Further, the role of fortification of rabadi beverage by probiotic culture was also assessed in this study at different temperatures (35, 42, and 45°C) of fermentation. In silico study has predicted the association of both tannic acid and ascorbic acid with the various human proteins responsible for the growth and development of the human immune system. In all used probiotic (Lactobacillus rhamnosus, Lactobacillus sp. and  Streptococcus faecalis), L. rhamnosus fortified rabadi beverage at continuous increasing temperature (35, 42, 45 °C) of non-autoclaved batch showed high content of TAC (36.83 ± 5.41 µg mL-1), TPC (46.1 ± 8.28 µg mL-1) and TFC (29.91 ± 7.73 µg mL-1); while decrease in tannins content (14.84 ± 4.64 µg mL-1) as compared to control [TAC (29.32 ± 3.17 µg mL-1), TPC (25.53 ± 5.75 µg mL-1), TFC (21.91 ± 5.95 µg mL-1), and Tannins (20.74 ± 3.43 µg mL-1)].  L. rhamnosus fortified rabadi beverage of non-autoclaved batch showed better results than Lactobacillus sp. and  S. faecalis fortified rabadi beverage of both batches (autoclaved and non-autoclaved); which in turn expressed the enhanced therapeutic activity of probiotic fortified rabadi beverage

The Rise of RNA-Based Therapeutics: Recent Advances and Therapeutic Potential

In recent years, RNA-based therapeutics have emerged as a groundbreaking field, offering innovative approaches for drug development and therapeutic interventions. This review article presents a comprehensive exploration of the advancements in RNA-based therapeutics, focusing on key modalities such as RNA interference (RNAi), antisense oligonucleotides (ASOs), messenger RNA (mRNA) vaccines, and other emerging RNA-based therapies. The introduction provides an insightful overview of the potential of RNA as a therapeutic target, highlighting its unique mechanisms of action and its transformative role in precision medicine. Subsequently, the review delves into the intricacies of RNAi, explaining the function of small interfering RNAs (siRNAs) and microRNAs (miRNAs) in selectively silencing disease-associated genes, thereby opening new avenues for therapeutic interventions. Antisense oligonucleotides (ASOs) are discussed in detail, elucidating how they target mRNA for degradation or modulation of splicing, offering promising solutions for treating genetic disorders, neurodegenerative diseases, and viral infections. Additionally, the groundbreaking success of mRNA vaccines is explored, with an emphasis on their role in combatting infectious diseases like COVID-19 and their potential application in cancer immunotherapy and other therapeutic areas. Addressing the critical issue of delivery challenges in RNA-based therapeutics, the review presents various strategies to enhance stability, cellular uptake, and minimize immunogenicity, thereby improving the effectiveness of these therapies in reaching their intended targets. Clinical successes and challenges of RNA-based therapeutics are critically evaluated, providing insights into ongoing clinical trials and approved therapies. Success stories underscore the transformative potential of RNA-based treatments, while safety concerns are addressed, paving the way for safer and more efficient therapeutic applications. The review concludes by exploring future prospects and innovations in the field, highlighting novel delivery strategies, advancements in RNA editing technologies, and the promise of combination therapies to augment therapeutic outcomes. Regulatory considerations and commercialization challenges are also discussed, offering an understanding of the regulatory landscape for RNA-based therapeutics and the potential for market growth. In conclusion, this review article serves as an informative resource for researchers, clinicians, and pharmaceutical professionals, shedding light on the rapid progress in RNA-based therapeutics and their potential to revolutionize disease treatment. By integrating knowledge from diverse sources, this review contributes to advancing the field and underscores the exciting possibilities of RNA-based interventions in improving patient outcomes and addressing unmet medical needs

Review Paper on Systematic Study of Leaf Disease Detection Using Accurate and Efficient ML Technique.

In recent years, plant diseases have posed significant threats to global food security and ecosystem stability. Timely detection and management of these diseases are imperative to mitigate their adverse effects. This paper introduces Foliage Guard, a novel smart plant leaf disease detector leveraging machine learning techniques for accurate and efficient disease identification. Leaves Guard employs state-of-the-art image processing algorithms to analyze leaf images captured using low-cost sensors or smartphones. The system utilizes a deep learning architecture trained on a diverse dataset of plant diseases to classify the health status of leaves accurately. Additionally, Foliage Guard incorporates real-time disease monitoring and alert mechanisms, enabling farmers and gardeners to take pro active measures against outbreaks. Through extensive experimentation and validation of various plant species, Foliage Guard demonstrates superior performance compared to existing approaches, with high accuracy and rapid processing times. The proposed system holds promise for revolutionizing plant disease management practices, offering a cost-effective and accessible solution for early disease detection and prevention in agriculture and horticulture sectors

Trigonocephaly pre- and post-operative evaluation by multidetector computed tomography

Trigonocephaly is the third most common single suture synostosis which is seen as bulging of the forehead due to early fusion of themetopic suture. It is linked with an increased level of neurodevelopmental delays. On imaging, multidetector computed tomographyshows anterior fontanelle ossification, hypoteliorism, narrowing of the anterior cranial fossa, and compensatory increase of themiddle cranial fossa with atrophic features of brain. Its reported incidence is 1 in 700-15,000 live births. Operative multipleosteotomies were done and imaged in follow-up

A rare neglected case of large leptomeningeal cyst: A case report

Leptomeningeal cysts are enlarging skull fractures that occur near post-traumatic encephalomalacia. The term cyst is usually a misnomer as it is not only a cyst but also an extension of encephalomalacia. They commonly occur after severe head trauma during the first 3 years of life (especially infancy) and almost never after 8 years of life. Herewith, we present a case of a 7-year-old female patient who presented to our hospital with left-sided weakness since 2 years and painless swelling over the scalp since 3 years giving past history of head trauma. Plain radiography, computed tomography, and magnetic resonance imaging were performed which showed classical findings of leptomeningeal cyst. We will be discussing about the causes and radiological findings which help in diagnosis as well as treatment planning

Phylogeography of mtDNA haplogroup R7 in the Indian peninsula.

BACKGROUND: Human genetic diversity observed in Indian subcontinent is second only to that of Africa. This implies an early settlement and demographic growth soon after the first 'Out-of-Africa' dispersal of anatomically modern humans in Late Pleistocene. In contrast to this perspective, linguistic diversity in India has been thought to derive from more recent population movements and episodes of contact. With the exception of Dravidian, which origin and relatedness to other language phyla is obscure, all the language families in India can be linked to language families spoken in different regions of Eurasia. Mitochondrial DNA and Y chromosome evidence has supported largely local evolution of the genetic lineages of the majority of Dravidian and Indo-European speaking populations, but there is no consensus yet on the question of whether the Munda (Austro-Asiatic) speaking populations originated in India or derive from a relatively recent migration from further East. RESULTS: Here, we report the analysis of 35 novel complete mtDNA sequences from India which refine the structure of Indian-specific varieties of haplogroup R. Detailed analysis of haplogroup R7, coupled with a survey of approximately 12,000 mtDNAs from caste and tribal groups over the entire Indian subcontinent, reveals that one of its more recently derived branches (R7a1), is particularly frequent among Munda-speaking tribal groups. This branch is nested within diverse R7 lineages found among Dravidian and Indo-European speakers of India. We have inferred from this that a subset of Munda-speaking groups have acquired R7 relatively recently. Furthermore, we find that the distribution of R7a1 within the Munda-speakers is largely restricted to one of the sub-branches (Kherwari) of northern Munda languages. This evidence does not support the hypothesis that the Austro-Asiatic speakers are the primary source of the R7 variation. Statistical analyses suggest a significant correlation between genetic variation and geography, rather than between genes and languages. CONCLUSION: Our high-resolution phylogeographic study, involving diverse linguistic groups in India, suggests that the high frequency of mtDNA haplogroup R7 among Munda speaking populations of India can be explained best by gene flow from linguistically different populations of Indian subcontinent. The conclusion is based on the observation that among Indo-Europeans, and particularly in Dravidians, the haplogroup is, despite its lower frequency, phylogenetically more divergent, while among the Munda speakers only one sub-clade of R7, i.e. R7a1, can be observed. It is noteworthy that though R7 is autochthonous to India, and arises from the root of hg R, its distribution and phylogeography in India is not uniform. This suggests the more ancient establishment of an autochthonous matrilineal genetic structure, and that isolation in the Pleistocene, lineage loss through drift, and endogamy of prehistoric and historic groups have greatly inhibited genetic homogenization and geographical uniformity.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Thermodynamic assessment of the Si-Zn, Mn-Si, Mg-Si-Zn and Mg-Mn-Si systems

The binary Si-Zn and Mn-Si systems have been critically evaluated based upon available phase equilibrium and thermodynamic data, and optimized model parameters have been obtained giving the Gibbs energies of all phases as functions of temperature and composition. The liquid solution has been modeled with the Modified Quasichemical Model (MQM) to account for the short-range-ordering. The results have been combined with those of our previous optimizations of the Mg-Si, Mg-Zn and Mg-Mn systems to predict the phase diagrams of the Mg-Si-Zn and Mg-Mn-Si systems. The predictions have been compared with available data. (C) 2008 Elsevier Ltd. All rights reserved.X112222sciescopu