Miracle-dz/UniFAR-FTUs huggingface dataset:
A novel multi-dimensional Eulerian approach to computational solid dynamics

M any problems in solid dynamics involve moving boundaries, finite elastoplastic deformations, and strong non-linear waves. Continuum modelling of such events is difficult on account of these characteristics, and there exist a number of inadequacies in current numerical algorithms. Furthermore, a comprehensive understanding of certain underlying processes is yet to be achieved which places a limit on the derivation of engineering models to simulate these occurrences. Much needed atomistic studies, capable of revealing much about the governing physical processes, remain limited by current computational resources. This thesis is devoted to targeting these difficulties by proposing new continuum numerical schemes and a means of studying both microand macro-scale behaviours via a dynamic coupling of continuum mechanics and molecular dynamics theory. Eulerian shock-capturing schemes have advantages for modelling problems involving complex non-linear wave structures and large deformations in solid media. Various numerical methods now exist for solving hyperbolic conservation laws that have yet to be applied to solid dynamics. A three-dimensional finite-volume scheme on fixed grids is proposed for elastoplastic solids. The scheme is based upon the Godunov flux method and thus requires solution of the Riemann problem. Both exact and approximate solutions are proposed for the special case of non-linear elasticity. An implicit algorithm is developed to allow for resolving rate-dependent inelastic deformations. The methods are tested against exact solutions in one-dimension, and symmetrical polar solutions in twoand three-dimensions. To account for multiple immiscible materials it is necessary to include some means of tracking material boundaries within a numerical scheme. A moving grid scheme is a simple means of accommodating transient boundaries. Interface tracking based on the use of level set functions is an attractive alternative for problems with sliding interfaces since it allows discontinuous velocity profiles at the material boundaries whilst employing fixed grids. Both of these methods are explored in the current context. A series of one-dimensional testcases have been carried out that demonstrate the ability of the numerical schemes to accurately resolve complex boundary conditions between interacting free surfaces. Where singularities occur in a system comprising solid materials, atomistic studies are invaluable for achieving a fundamental insight into the governing physical processes. However where non-linear waves are generated, domain size proves to be a limiting factor in achieving solutions free from numerical artifacts. A domain decomposition multi-scale modelling strategy is developed that couples the Eulerian shock capturing scheme with a molecular dynamics solver. The method is demonstrated for one-dimensional testcases involving strong shear waves and multiple components. Attention is devoted to resolving transient wave propagation free from spurious wave reflections through investigation of the numerical parameters.
Wire Arc Additive Manufacturing (WAAM) for Aluminum-Lithium Alloys: A Review

Out of all the metal additive manufacturing (AM) techniques, the directed energy deposition (DED) technique, and particularly the wire-based one, are of great interest due to their rapid production. In addition, they are recognized as being the fastest technique capable of producing fully functional structural parts, near-net-shape products with complex geometry and almost unlimited size. There are several wire-based systems, such as plasma arc welding and laser melting deposition, depending on the heat source. The main drawback is the lack of commercially available wire; for instance, the absence of high-strength aluminum alloy wires. Therefore, this review covers conventional and innovative processes of wire production and includes a summary of the Al-Cu-Li alloys with the most industrial interest in order to foment and promote the selection of the most suitable wire compositions. The role of each alloying element is key for specific wire design in WAAM; this review describes the role of each element (typically strengthening by age hardening, solid solution and grain size reduction) with special attention to lithium. At the same time, the defects in the WAAM part limit its applicability. For this reason, all the defects related to the WAAM process, together with those related to the chemical composition of the alloy, are mentioned. Finally, future developments are summarized, encompassing the most suitable techniques for Al-Cu-Li alloys, such as PMC (pulse multicontrol) and CMT (cold metal transfer).
Self-Powered Synchronized Switching Interface Circuit for Piezoelectric Footstep Energy Harvesting

Piezoelectric Vibration converters are nowadays gaining importance for supplying low-powered sensor nodes and wearable electronic devices. Energy management interfaces are thereby needed to ensure voltage compatibility between the harvester element and the electric load. To improve power extraction ability, resonant interfaces such as Parallel Synchronized Switch Harvesting on Inductor (P-SSHI) have been proposed. The main challenges for designing this type of energy management circuits are to realise self-powered solutions and increase the energy efficiency and adaptability of the interface for low-power operation modes corresponding to low frequencies and irregular vibration mechanical energy sources. In this work, a novel Self-Powered (SP P-SSHI) energy management circuit is proposed which is able to harvest energy from piezoelectric converters at low frequencies and irregular chock like footstep input excitations. It has a good power extraction ability and is adaptable for different storage capacitors and loads. As a proof of concept, a piezoelectric shoe insole with six integrated parallel piezoelectric sensors (PEts) was designed and implemented to validate the performance of the energy management interface circuit. Under a vibration excitation of 1 Hz corresponding to a (moderate walking speed), the maximum reached efficiency and power of the proposed interface is 83.02% and 3.6 mW respectively for the designed insole, a 10 kΩ resistive load and a 10 μF storage capacitor. The enhanced SP-PSSHI circuit was validated to charge a 10 μF capacitor to 6 V in 3.94 s and a 1 mF capacitor to 3.2 V in 27.64 s. The proposed energy management interface has a cold start-up ability and was also validated to charge a (65 mAh, 3.1 V) maganese dioxide coin cell Lithium battery (ML 2032), demonstrating the ability of the proposed wearable piezoelectric energy harvesting system to provide an autonomous power supply for wearable wireless sensors.
The Emerging Role of m6A Modification in Endocrine Cancer

Simple Summary Endocrine tumors often cause hormonal imbalances and sometimes hormone syndrome. Generally, the prognosis of patients with metastatic endocrine malignancies is poor due to recurrence and treatment failure. Aberrant expression of m6A may disrupt the development and occurrence of malignancies. We provide a theoretical foundation for the development of new diagnostic markers and therapeutic techniques based on m6A alteration and regulators in endocrine cancers. Abstract With the development of RNA modification research, N6-methyladenosine (m6A) is regarded as one of the most important internal epigenetic modifications of eukaryotic mRNA. It is also regulated by methylase, demethylase, and protein preferentially recognizing the m6A modification. This dynamic and reversible post-transcriptional RNA alteration has steadily become the focus of cancer research. It can increase tumor stem cell self-renewal and cell proliferation. The m6A-modified genes may be the primary focus for cancer breakthroughs. Although some endocrine cancers are rare, they may have a high mortality rate. As a result, it is critical to recognize the significance of endocrine cancers and identify new therapeutic targets that will aid in improving disease treatment and prognosis. We summarized the latest experimental progress in the m6A modification in endocrine cancers and proposed the m6A alteration as a potential diagnostic marker for endocrine malignancies.
Principal Component Analysis in Meteorology and Oceanography

List of figures. List of tables. 1. Introduction. An overview of principal component analysis (PCA). Outline of the book. A brief history of PCA. Acknowledgements. 2. Algebraic foundations of PCA. Introductory example: Bivariate data sets. Principal component analysis: Real-valued scalar fields. Principal component analysis: Complex-valued scalar fields, and beyond. Bibliographic notes and miscellaneous topics. 3. Dynamical origins of PCA. One-dimensional harmonic motion. Two-dimensional wave motion. Dynamical origins of linear regression (LR). Random processes and Karhunen-Loeve analysis. Stationary processes and PCA. Bibliographic notes. 4. Extensions of PCA to multivariate fields. Categories of data and modes of analysis. Local PCA of a general vector field. Global PCA of a general vector field: Time-modulation form. Global PCA of a general vector field: Space-modulation form. PCA of spectral components of a general vector field. Bibliographic notes and miscellaneous topics. 5. Selection rules for PCA. Random reference data sets. Dynamical origins of the dominant-variance selection rules. Rule A 4 . Rule N. Rule M. Comments on dominant-variance rules. Dynamical origins of the time-history selection rules. Rule KS2. Rules AMPl. Rule Q. Selection rules for vector-valued fields. A space-map selection rule. Bibliographic notes and miscellaneous topics. 6. Factor analysis (FA) and PCA. Comparison of PCA, LRA, and FA. The central problems of FA. Bibliographic notes. 7. Diagnostic procedures via PCA and FA. Dual interpretations of a data set: state space and sample space. Interpreting E-frames in PCA state space. Informative and uninformative E-frames in PCA state space. Rotating E-frames in PCA state space (varimax). Projections onto E-frames in PCA state space (procrustes). Interpreting A-frames in PCA sample space. Rotating A-frames in PCA sample space (varimax). Projections onto A-frames in PCA sample space (procrustes). Detecting clusters of points in PCA state or sample spaces. The analogous PCA interpretations and transformations in FA. Bibliographic notes. 8. Canonical correlation analysis (CCA) and PCA. The singular value decomposition (SVD) of two data sets. The correlation probe. Maximizing the correlation function g(r,s). Canonical correlations. Canonical component representations of data sets. Selection rules for CCA. Bibliographic notes. 9. Linear regression analysis (LRA) and PCA. Basic regression equations. Regression using PCA frames. Regression using CCA frames. Regression hindcast skill. Regression signal-to-noise ratio. Significant hindcast skill. Bibliographic notes. 10. Statistical-dynamical models and PCA. Example 1: A linear two-dimensional damped-wave model. Example 2: Linearized primitive equations for the atmosphere and oceans. Bibliographic notes. 11. The eigenvector-partition problem. PCA on partitioned domains. Iterative improvement of the optimal combinations.
The Chromatin Landscape around DNA Double-Strand Breaks in Yeast and Its Influence on DNA Repair Pathway Choice

DNA double-strand breaks (DSBs) are harmful DNA lesions, which elicit catastrophic consequences for genome stability if not properly repaired. DSBs can be repaired by either non-homologous end joining (NHEJ) or homologous recombination (HR). The choice between these two pathways depends on which proteins bind to the DSB ends and how their action is regulated. NHEJ initiates with the binding of the Ku complex to the DNA ends, while HR is initiated by the nucleolytic degradation of the 5′-ended DNA strands, which requires several DNA nucleases/helicases and generates single-stranded DNA overhangs. DSB repair occurs within a precisely organized chromatin environment, where the DNA is wrapped around histone octamers to form the nucleosomes. Nucleosomes impose a barrier to the DNA end processing and repair machinery. Chromatin organization around a DSB is modified to allow proper DSB repair either by the removal of entire nucleosomes, thanks to the action of chromatin remodeling factors, or by post-translational modifications of histones, thus increasing chromatin flexibility and the accessibility of repair enzymes to the DNA. Here, we review histone post-translational modifications occurring around a DSB in the yeast Saccharomyces cerevisiae and their role in DSB repair, with particular attention to DSB repair pathway choice.
Targeting Mitochondrial IDH2 Enhances Antitumor Activity of Cisplatin in Lung Cancer via ROS-Mediated Mechanism

Mitochondrial isocitrate dehydrogenase 2 (IDH2) is an important metabolic enzyme in the tricarboxylic acid cycle (TCA) cycle. Our previous study showed that high expression of wild-type IDH2 promotes the proliferation of lung cancer cells. This study aims to test the potential of targeting IDH2 as a therapeutic strategy to inhibit lung cancer in vitro and in vivo. First, we analyzed the available data from the databases gene expression omnibus (GEO) database to evaluate the clinical relevance of IDH2 expression in affecting lung cancer patient survival. We then generated a stable IDH2-knockdown lung cancer cell line using a lentivirus-based method for in vitro and in vivo study. Cell growth, apoptosis, cell viability, and colony formation assays were conducted to test the sensitivity of lung cancer cells with different IDH2 expression status to cisplatin or radiation treatment in vitro. For mechanistic study, Cellular oxygen consumption and extracellular acidification rates were measured using a Seahorse metabolic analyzer, and reactive oxygen species (ROS) generation was analyzed using flow cytometry. An animal study using a xenograft tumor model was performed to further evaluate the in vivo therapeutic effect on tumor growth. We found that high IDH2 expression was associated with poor survival in lung cancer patients undergoing chemotherapy. Inhibition of IDH2 significantly enhanced the anticancer activity of cisplatin and also increased the effect of radiation against lung cancer cells. IDH2 was upregulated in cisplatin-resistant lung cancer cells, which could be sensitized by targeted inhibition of IDH2. Mechanistic study showed that abrogation of IDH2 caused only minimal changes in oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) in lung cancer cells, but induced a significant increase in ROS, which rendered the cancer cells more sensitive to cisplatin. Pretreatment of lung cancer cells with the ROS scavenger N-acetyl-cysteine could partially rescue cells from the cytotoxic effect of cisplatin and IDH2 inhibition. Importantly, abrogation of IDH2 significantly increased the sensitivity of lung cancer cells to cisplatin in vivo.
Electron-shading effect on the horizontal aligned growth of carbon nanotubes

Based on the well-accepted electron-shading theory during plasma processing, we designed microstructures to control the local built-in electric-field on the substrate surface. The distortion magnitude of the electric-field is largest near the sidewalls of the microstructures, creating a horizontal electric-field in this region. We showed that the horizontally aligned carbon nanotubes (CNTs) were grown by making use of this built-in electric-field during the plasma-enhanced chemical vapor deposition process, with a tactical choice of geometries and materials of the microstructures on the substrate. This technique opens up a way to selectively and controllably grow horizontally aligned CNTs on the substrate surface.
A Novel Micro-Scale Plastic Deformation Feature on a Bulk Metallic Glass Surface under Laser Shock Peening

Laser shocking peening is a widely applied surface treatment technique that can effectively improve the fatigue properties of metal parts. We observe many micro-scale arc plastic steps on the surface of Zr47.9Ti0. 3Ni3.1Cu39. 3Al9.4 metallic glass subjected to the ultra-high pressure and strain rate induced by laser shock peening. The scanning electronic microscopy and atomic force microscopy show that the arc plastic step (APS) has an arc boundary, 50-300 nm step height, 5-50 mu m radius and no preferable direction. These APSs have the ability to accommodate plastic deformation in the same way as shear band. This may indicate a new mechanism to accommodate the plastic deformation in amorphous metallic glass under high pressure, ultra-high strain rates, and short duration.
Dual approaches to strictly positive real controller synthesis with a H2 performance using linear matrix inequalities

The synthesis of controllers that minimize a H2 performance index subject to a strictly positive real (SPR) constraint is considered. Two controller synthesis methods are presented that are then combined into an iterative algorithm. Each method synthesizes optimal SPR controllers by posing a convex optimization problem where constraints are enforced via linear matrix inequalities. Additionally, each method fixes the controller state‐feedback gain matrix and finds an observer gain matrix such that an upper bound on the closed‐loop H2 ‐norm is minimized and the controller is SPR. The first method retools the standard H2 ‐optimal control problem by using a common Lyapunov matrix variable to satisfy both the H2 criteria and the SPR constraint. The second method overcomes bilinear matrix inequality issues associated with the H2 performance and the SPR constraint by employing a completing the square method and an overbounding technique. Both synthesis methods are used within an iterative scheme to find optimal SPR controllers in a sequential manner. Comparison of our synthesis methods to existing methods in the literature is presented. Copyright © 2012 John Wiley & Sons, Ltd.
Is It Time to Reconsider the U.S. Recommendations for Dietary Protein and Amino Acid Intake?

Since the U.S. Institute of Medicine’s recommendations on protein and amino acid intake in 2005, new information supports the need to re-evaluate these recommendations. New lines of evidence include: (1) re-analysis/re-interpretation of nitrogen balance data; (2) results from indicator amino acid oxidation studies; (3) studies of positive functional outcomes associated with protein intakes higher than recommended; (4) dietary guidance and protein recommendations from some professional nutrition societies; and (5) recognition that the synthesis of certain dispensable amino acids may be insufficient to meet physiological requirements more often than previously understood. The empirical estimates, theoretical calculations and clinical functional outcomes converge on a similar theme, that recommendations for intake of protein and some amino acids may be too low in several populations, including for older adults (≥65 years), pregnant and lactating women, and healthy children older than 3 years. Additional influential factors that should be considered are protein quality that meets operational sufficiency (adequate intake to support healthy functional outcomes), interactions between protein and energy intake, and functional roles of amino acids which could impact the pool of available amino acids for use in protein synthesis. Going forward, the definition of “adequacy” as it pertains to protein and amino acid intake recommendations must take into consideration these critical factors.
Study of a fast ablative capillary discharge dedicated to soft x-ray production

A capillary discharge has been developed to produce pulses of intense soft x-ray radiation of tens of nanoseconds duration. The soft x-ray photons were emitted in a plasma column resulting from polyethylene in capillary wall ablation. The spectrum was dominated by the C IV, C V, and C VI emission lines in the soft x-ray spectral range. The experimental value of the electrical circuit inductance has been measured and compared to the calculated one. The electron temperature was estimated to be higher than 50 eV from the plasma resistivity measurement. The time dependence of the electron density outside the capillary channel has been determined using spectroscopic measurement in the visible range. The time dependence of the electron temperature has been determined from the intensity ratio of C V and C VI emission lines, using a collisional radiative equilibrium code.
Modified Korteweg–de Vries equation in a negative ion rich hot adiabatic dusty plasma with non-thermal ion and trapped electron

In this report, the investigation of the properties of dust acoustic (DA) solitary wave propagation in an adiabatic dusty plasma including the effect of the non-thermal ions and trapped electrons is presented. The reductive perturbation method has been employed to derive the modified Korteweg–de Vries (mK-dV) equation for dust acoustic solitary waves in a homogeneous, unmagnetized, and collisionless plasma whose constituents are electrons, singly charged positive ions, singly charged negative ions, and massive charged dust particles. The stationary analytical solution of the mK-dV equation is numerically analyzed and where the effect of various dusty plasma constituents DA solitary wave propagation is taken into account. It is observed that both the ions in dusty plasma play as a key role for the formation of both rarefactive as well as the compressive DA solitary waves and also the ion concentration controls the transformation of negative to positive potentials of the waves.
Parametric and nonparametric analysis of simultaneous equation models with latent variables: theory and applications

Cette these de doctorat est composee de trois chapitres. La principale contribution consiste a presenter deux cadres theoriques, parametrique et non-parametrique, pour faire des comparaisons et evaluations des concepts theoriques non-observables utilises dans differents contextes tels que le bien-etre, le developpement, la sante et l’inegalite entre autres.Le premier chapitre presente le modele parametrique avec une methode d'estimation et un exemple numerique avec des simulations. Le deuxieme chapitre est une application, sur des donnees francaises, de ce type de modeles dans le contexte de la sante, en operationnalisant l'approche des capabilites d'Amartya Sen. Finalement, le troisieme chapitre consiste en une alternative non-parametrique accompagnee d'une application sur des donnees indiennes dans le contexte du bien-etre, pour tester la dominance stochastique multivariee de premier ordre.