G. Lusztig
The history of the canonical basis and crystal basis of a quantized enveloping algebra and its representations is presented
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G. Lusztig
The history of the canonical basis and crystal basis of a quantized enveloping algebra and its representations is presented
Mona Alexandra ORZA (VRAJA), Cristina Silvia NISTOR
Linking university performance to sustainability is possible through the university’s third mission: environmental responsibility. To better understand the concepts, practices and challenges of sustainability, the role of literature is crucial; therefore, this paper reviews the existing literature on academic performance and sustainability using a bibliometric analysis for articles published in the Web of Science database between 2009 and 2023. This research intends to contribute to recent stream of research on sustainability implementation by identifying the relationship between performance and sustainability in university missions. To date, there have been only a few bibliometric analyses the relationship between performance and sustainability in the public higher education sector. However, no one has discussed the perspective of the link between performance and sustainability through the university mission, and this research intends to fill this gap. The results show that in the last three years, the interest in performance and sustainability has led to an increase of up to 66% in articles on sustainability and performance in the public university system. Spain appears to be the main contributor to the research articles related to the area of interest. Research in the public university system on concepts related to sustainability and performance is still at an early stage, yet has seen considerable progress over the past few years. JEL classification: A11; O20; Q01. Article History: Received: 21 March 2025; Reviewed: 28 April 2025; Accepted: 30 May 2025; Available online: 27 June 2025.
J. Segalés, Mariona Puig, J. Rodón et al.
Significance COVID-19 is the most devastating pandemic in recent history. As with many emerging infectious diseases, it is of zoonotic origin, meaning that animals played a major role in the initial transmission events. Despite SARS-CoV-2 being highly adapted to jump from human to human, several animal species are naturally susceptible to SARS-CoV-2, including pets such as cats. In the present report, a cat from a family with several relatives affected by COVID-19 developed severe respiratory clinical signs, leading to humanitarian euthanasia. Due to the suspicion of a potential COVID-19 infection in the cat, different antemortem and postmortem tests were assayed. The clinical condition was finally attributed to a feline hypertrophic cardiomyopathy, but the animal was also infected by SARS-CoV-2. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of COVID-19, is considered a zoonotic pathogen mainly transmitted human to human. Few reports indicate that pets may be exposed to the virus. The present report describes a cat suffering from severe respiratory distress and thrombocytopenia living with a family with several members affected by COVID-19. Clinical signs of the cat prompted humanitarian euthanasia and a detailed postmortem investigation to assess whether a COVID-19−like disease was causing the condition. Necropsy results showed the animal suffered from feline hypertrophic cardiomyopathy and severe pulmonary edema and thrombosis. SARS-CoV-2 RNA was only detected in nasal swab, nasal turbinates, and mesenteric lymph node, but no evidence of histopathological lesions compatible with a viral infection were detected. The cat seroconverted against SARS-CoV-2, further evidencing a productive infection in this animal. We conclude that the animal had a subclinical SARS-CoV-2 infection concomitant to an unrelated cardiomyopathy that led to euthanasia.
Muhammad Zubair Khan, Oleg E. Peil, Apoorva Sharma et al.
In the rapidly expanding field of two-dimensional materials, magnetic monolayers show great promise for the future applications in nanoelectronics, data storage, and sensing. The research in intrinsically magnetic two-dimensional materials mainly focuses on synthetic iodide and telluride based compounds, which inherently suffer from the lack of ambient stability. So far, naturally occurring layered magnetic materials have been vastly overlooked. These minerals offer a unique opportunity to explore air-stable complex layered systems with high concentration of local moment bearing ions. We demonstrate magnetic ordering in iron-rich two-dimensional phyllosilicates, focusing on mineral species of minnesotaite, annite, and biotite. These are naturally occurring van der Waals magnetic materials which integrate local moment baring ions of iron via magnesium/aluminium substitution in their octahedral sites. Due to self-inherent capping by silicate/aluminate tetrahedral groups, ultra-thin layers are air-stable. Chemical characterization, quantitative elemental analysis, and iron oxidation states were determined via Raman spectroscopy, wavelength disperse X-ray spectroscopy, X-ray absorption spectroscopy, and X-ray photoelectron spectroscopy. Superconducting quantum interference device magnetometry measurements were performed to examine the magnetic ordering. These layered materials exhibit paramagnetic or superparamagnetic characteristics at room temperature. At low temperature ferrimagnetic or antiferromagnetic ordering occurs, with the critical ordering temperature of 38.7 K for minnesotaite, 36.1 K for annite, and 4.9 K for biotite. In-field magnetic force microscopy on iron bearing phyllosilicates confirmed the paramagnetic response at room temperature, present down to monolayers.
Antonio Herrera, John Markoff
Mercedes Camino
The the Setting investigates Spanish exploration, mapping and settlement of the Paci fi c to document “ a new history of the early modern cartographic imagin-ation Padrón divides his work into eight chapters that show how Spain ’ s “ geopolitical imaginary resisted the twin ideas that the New World was entirely separate from Asia and that the Paci fi c geographical and even ontological boundary between these two parts of the world and their inhabitants ” Resistance to segregation, according to Padrón, is apparent in maps and “ cartographic literature ” that deploy “ a variety of metageographical frameworks available for mapping the world ” (7). The Indies of the Setting Sun these “ frameworks construct fi to
Arnaud Mazier, Alexandre Bilger, Antonio E. Forte et al.
In this paper, we develop a framework for solving inverse deformation problems using the FEniCS Project finite element software. We validate our approach with experimental imaging data acquired from a soft silicone beam under gravity. In contrast with inverse iterative algorithms that require multiple solutions of a standard elasticity problem, the proposed method can compute the undeformed configuration by solving only one modified elasticity problem. This modified problem has a complexity comparable to the standard one. The framework is implemented within an open-source pipeline enabling the direct and inverse deformation simulation directly from imaging data. We use the high-level Unified Form Language (UFL) of the FEniCS Project to express the finite element model in variational form and to automatically derive the consistent Jacobian. Consequently, the design of the pipeline is flexible: for example, it allows the modification of the constitutive models by changing a single line of code. We include a complete working example showing the inverse deformation of a beam deformed by gravity as supplementary material.
Galina Sinkevich
A short history of Russian researches in Chinese astronomy in 19-20 centuries
Ignacio Rodríguez Temiño, Ana Yáñez
José María Gómez Herráez
La guerra de 1936-1939 no significó simplemente una orientación propagandística de la historia. La observación del pasado sirvió para estimular de distintas formas el espíritu de combate, resistencia y colaboración interna, pero también las transformaciones socioeconómicas e institucionales en cada zona influyeron en la selección de temas, en los silencios y en las interpretaciones. Además, existían variaciones en función del medio de expresión. En este examen se contextualizan y comentan las perspectivas seguidas en algunos trabajos agrupados en cuatro categorías. Tres corresponden a la zona republicana: textos de inspiración liberal-democrática, de tipo obrerista y de tipo catalanista. De la zona controlada por los sublevados se observan las intervenciones en un curso para maestros.
Mikhail G. Katz
We compare several approaches to the history of mathematics recently proposed by Blasjo, Fraser--Schroter, Fried, and others. We argue that tools from both mathematics and history are essential for a meaningful history of the discipline. In an extension of the Unguru-Weil controversy over the concept of geometric algebra, Michael Fried presents a case against both Andre Weil the "privileged observer" and Pierre de Fermat the "mathematical conqueror." We analyze Fried's version of Unguru's alleged polarity between a historian's and a mathematician's history. We identify some axioms of Friedian historiographic ideology, and propose a thought experiment to gauge its pertinence. Unguru and his disciples Corry, Fried, and Rowe have described Freudenthal, van der Waerden, and Weil as Platonists but provided no evidence; we provide evidence to the contrary. We analyze how the various historiographic approaches play themselves out in the study of the pioneers of mathematical analysis including Fermat, Leibniz, Euler, and Cauchy.
Galina I. Sinkevich
The history of the development of the concept of complex numbers from the 16th to 19th centuries. The origin and refinement of the geometric and physical meaning of complex numbers, the emergence of vectoral analysis.
Asier Minondo
The COVID-19 crisis has led to the sharpest collapse in the Spanish trade of goods and services in recent decades. The containment measures adopted to arrest the spread of the virus have caused an especially intense fall of trade in services. Spain's export specialization in transport equipment, capital and outdoor goods, and services that rely on the movement of people has made the COVID-19 trade crisis more intense in Spain than in the rest of the European Union. However, the nature of the collapse suggests that trade in goods can recover swiftly when the health crisis ends. On the other hand, COVID-19 may have a long-term negative impact on the trade of services that rely on the movement of people.
Javier Suárez, Javier Suárez, Vanessa Triviño
Contemporary biological research has suggested that some host–microbiome multispecies systems (referred to as “holobionts”) can in certain circumstances evolve as unique biological individual, thus being a unit of selection in evolution. If this is so, then it is arguably the case that some biological adaptations have evolved at the level of the multispecies system, what we call hologenomic adaptations. However, no research has yet been devoted to investigating their nature, or how these adaptations can be distinguished from adaptations at the species-level (genomic adaptations). In this paper, we cover this gap by investigating the nature of hologenomic adaptations. By drawing on the case of the evolution of sanguivory diet in vampire bats, we argue that a trait constitutes a hologenomic adaptation when its evolution can only be explained if the holobiont is considered the biological individual that manifests this adaptation, while the bacterial taxa that bear the trait are only opportunistic beneficiaries of it. We then use the philosophical notions of emergence and inter-identity to explain the nature of this form of individuality and argue why it is special of holobionts. Overall, our paper illustrates how the use of philosophical concepts can illuminate scientific discussions, in the trend of what has recently been called metaphysics of biology.
Jacob Hauser, Barak Shoshany
If time travel is possible, it seems to inevitably lead to paradoxes. These include consistency paradoxes, such as the famous grandfather paradox, and bootstrap paradoxes, where something is created out of nothing. One proposed class of resolutions to these paradoxes allows for multiple histories (or timelines), such that any changes to the past occur in a new history, independent of the one where the time traveler originated. We introduce a simple mathematical model for a spacetime with a time machine, and suggest two possible multiple-histories models, making use of branching spacetimes and covering spaces respectively. We use these models to construct novel and concrete examples of multiple-histories resolutions to time travel paradoxes, and we explore questions such as whether one can ever come back to a previously visited history and whether a finite or infinite number of histories is required. Interestingly, we find that the histories may be finite and cyclic under certain assumptions, in a way which extends the Novikov self-consistency conjecture to multiple histories and exhibits hybrid behavior combining the two. Investigating these cyclic histories, we rigorously determine how many histories are needed to fully resolve time travel paradoxes for particular laws of physics. Finally, we discuss how observers may experimentally distinguish between multiple histories and the Hawking and Novikov conjectures.
Peyman Nasehpour
In this note, we investigate the history of algebra briefly. We particularly focus on the history of rings, semirings, and the distributive law.
Adam Burrows
The histories of core-collapse supernova theory and of neutrino physics have paralleled one another for more than seventy years. Almost every development in neutrino physics necessitated modifications in supernova models. What has emerged is a complex and rich dynamical scenario for stellar death that is being progressively better tested by increasingly sophisiticated computer simulations. Though there is still much to learn about the agency and details of supernova explosions, whatever final theory emerges will have the neutrino at its core. I summarize in this brief contribution some of the salient developments in neutrino physics as they related to supernova theory, while avoiding any attempt to review the hundreds of pivotal papers that have pushed supernova theory forward. My goal has been merely to highlight the debt of supernova astrophysics to neutrino physics.
Alexander I. Nazarov, Galina I. Sinkevich
The first half of the 20th century in the history of Russian mathematics is striking with a combination of dramaticism, sometimes a tragedy, and outstanding achievements. The paper is devoted to St. Petersburg-Leningrad Mathematical School. It is based on a chapter in the multi-author monograph "Mathematical Petersburg. History, science, sights" (SPb: Educational projects, 2018, 336 pp. in Russian).
Ricardo Córdoba de la Llave
Karim Ghorbal
Reseña bibliográfica
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