Littérature scientifique sur le sujet « Processi di Lévy »

Mangongkal Holi yaitu ritual upacara adat tradisi Batak Toba yang masih dilestarikan, dengan proses penggalian makam orang yang sudah lama wafat/meninggal untuk diambil tulang-belulangnya dan dipindahkan ke tempat yang baru yaitu sebuah tugu atau batu napir. Tujuan dari upacara kematian tradisi Batak yaitu menjali silaturahmi antar kekerabatan marga. Untuk menguraikan rangkaian pelaksanaan tersebut menggunakan metode penelitiandeskriptif analisis dengan langkah-langkah; studi pustaka, studi observasi, dan studidokumentasi melalui teori analisis struktural Lévi-Strauss. Hasil dari penelitian ini menemukan adanya transformasi bentuk dalam rangkaian pra-acara, pelaksanaan acara, pesta adat, dan pasca-acara. Adapun temuan menggunakan analisis Deep Structure terdapat empat unsur kebudayaan yang masih lekat untuk diterapkandiantaranya: taburan uang di kuburan, rumah sakti sebagai tempat pemberkatan, toleransi mangongkal holi dalam keberagaman agama, dan jeruk purut serta serbuk kunyit sebagai bentuk kesucian. Hal tersebut menjadi adanya transformasi struktur dan makna pada upacara ritual kematian Mangongkal Holi pada marga Nainggolan. Kata Kunci: Mangongkal Holi, Upacara kematian, Batak TobaMangongkal Holi is a traditional ceremonial ritual of the Toba Batak tradition that is still preserved, with the process of excavating the graves of people who have long died to take their bones and move them to a new place, namely a monument or stone napir. The purpose of the death ceremony of the Batak tradition is to establish a relationship between clan kinship. To describe the series ofimplementations using descriptive analysis research methods with steps; literature study, observational study, and documentation study through Lévi-Strauss structural analysis theory.The results of this study found a transformation of form in a series of pre-event, event implementation, traditional party, and post-event. As for the findings using Deep Structure analysis, there are four cultural elements that are still attached to be applied, including: the sprinkling of money in graves, a sacred house as a place of blessing, tolerance for mangongkal holi in religious diversity, and kaffir lime and turmeric powder as a form of holiness. This is a transformation of structure and meaning in the ritual ceremony of the death of Mangongkal Holi in the Nainggolan clan. Keyword: Mangongkal Holi, Upacara kematian, Batak Toba

The Artemisia argyi Lévl. et Van. growing in the surrounding areas of Qichun County in China are called Qiai (QA). Qiai is a crop that can be used both as food and in traditional folk medicine. However, detailed qualitative and quantitative analyses of its compounds remain scarce. The process of identifying chemical structures in complex natural products can be streamlined by combining UPLC-Q-TOF/MS data with the UNIFI information management platform and its embedded Traditional Medicine Library. For the first time, 68 compounds in QA were reported by the method in this study. The method of simultaneous quantification of 14 active components in QA using UPLC-TQ-MS/MS was reported for the first time. Following a screening of the activity of QA 70% methanol total extract and its three fractions (petroleum ether, ethyl acetate, and water), it was discovered that the ethyl acetate fraction enriched with flavonoids such as eupatilin and jaceosidin had the strongest anti-inflammatory activity, while the water fraction enriched with chlorogenic acid derivatives such as 3,5-di-O-caffeoylquinic acid had the strongest antioxidant and antibacterial activity. The results provided the theoretical basis for the use of QA in the food and pharmaceutical industries.

«For a place to leave an impression on us, it must be made of time as well as space – of its past, its history, its culture» (Sciascia, 1987). Architecture is one the many disciplines which, due to their heteronomous nature, aspire to represent the past, present and future of a community. Just as the construction of buildings is not merely a response to a need, but rather an act that incorporates the concrete translation of desires and aspirations, so too do music, philosophy, and the figurative arts reflect contemporary themes in their evolution. The fragmentation of skills, the specialisation of knowledge, the rapid modification of the tools we work with, the digitalisation and hyperdevelopment of communication are all phenomena that have a substantial impact on the evolution of disciplines in a reciprocal interaction with the intangible values of a community – economic, social and cultural – as well as the material assets of the places where it expresses itself. Interpreting heteronomy as a condition in which an action is not guided by an autonomous principle that is intrinsic to the discipline, but rather determined by its interaction with external factors, a theoretical reflection on the evolution of the tools of knowledge and creation has the task of defining possible scenarios capable of tackling the risk of losing an ability to synthesise the relationships between the conditions that define the identity of architecture itself. The challenge of complexity is rooted in social, technological and environmental shifts: a challenge that involves space, a material resource, in its global scale and its human measure; and time, an immaterial resource, nowadays evaluated in terms of speed and flexibility, but also duration and permanence. These elements impact upon the project as a whole, as a combination of multiple forms of knowledge which, given their constant evolution, is subject to continuous comparison. The cultural debate has investigated at length the topic of art being forced to devote itself to heteronomy whilst also retaining a need for aesthetic autonomy. The risk of forgetting its own ontological status, of losing its own identity in the fragmentation and entropy of the contemporary world, finds an answer in the idea of design as a synthesis between an artistic idea and the social and environmental conditions in which it is places, configuring itself as an element capable of reconciling the antithetical drives towards an autonomous vision of the work, on the one hand, and a heteronomous one linked to its geographical, cultural, sociological and psychological characteristics, on the other. In the systemic and concerted working process so intrinsic to disciplines such as filmmaking and music – but also the visual arts or even philosophy – the act of designing is the expression of the relationship with a community of individuals whose actions are based on a role that is as social as it is technical, given that they act based on material and immaterial values of a public nature. If indeed the sciences – as Thomas Kuhn demonstrated in his writings on the scientific revolutions – cannot be understood without their historical dimension, then disciplines such as those addressed in this Dossier represent cultural phenomena that can only truly be understood in their entirety when considered in the context of their era and the many factors that fed into their creation. However, precisely as demonstrated by Kuhn’s theories (Kuhn, 1987), their evolution also consists of “scientific revolutions”: moments of disruption capable of changing the community’s attitude towards the discipline itself and, perhaps more importantly, its paradigms. Music, cinema, art, architecture and philosophy are all expressions of that which makes us human, in all its complexity: divided and confined to their own disciplinary fields, they are not capable of expressing the poetic quality of life and thus «making people feel and become aware of the aesthetic feeling» (Morin, 2019). Emanuele Coccia, an internationally renowned philosopher and associate professor at the École des Hautes Études en Sciences Sociales in Paris, imagines a world in which everything you see is the product of an intentionality articulated by human, non-human and non-living actors. Design – not only anthropocentric design – is the most universal power in the world. Every living being can, in effect, design the world, but at the same time, every agent of matter can also design, and it is the interplay between these elements that creates a continuous metamorphosis of our environment. In other words, being alive is not a necessary condition for being a designer. The two anthropologists Alfred Gell and Philippe Descola, in their writings on Western society and nature, present contrasting views on the presence of the soul/animism in nature. The result is a sort of architecture of the landscape, in which nature itself is imbued with a sense of design intentionality that exists in a continuum with mankind. Edoardo Tresoldi, a young Italian sculptor, is one of the latest exponents of the heteronomy of architecture, which rejects the limiting confines of individual disciplines so as to imagine a transversal vision of the environment and its construction. Through the interplay of transparencies created with ephemeral metal structures, Tresoldi exalts the geometrical qualities of this raw material, going beyond the simple spatiotemporal dimension to establish a dialogue between place and the artistic representation thereof. Tresoldi recounts this journey of his through five themes: Place, because architecture in itself is markedly conditioned by its context, as is – in his case – art; Design, that is the act of envisaging the work, which is ultimately influenced by everything around us and our imagination; Time, as art is characterised by a potential interweaving, a continuity in the creative processes influenced by the history of the place; Material, or rather, materiality and the duality between the technical and artistic parts; and, finally, “What’s Next”, exploring the idea of what the future holds for us. On this last point, Tresoldi imagines his works further opening up to a diversified range of skills in a way that would also carve out new professional profiles for young people. Cristina Frosini, Director of the Milan Conservatory, with a contribution on music – «the supreme mystery of the sciences of man» (Lévi-Strauss, 2004) – offers reflections on a field with deep affinities with the discipline of architecture, with both sharing a strong relationship between composition and execution. The sheer vastness of musical expression, from the precision of the classical score to the freedom of interpretation exemplified by the conductor or the improvising jazz musician, sees the concepts of overall rhythm and melody, the homogeneity and identity of different instruments, and the circularity of the process as the key themes of music as a public art whose creative process has always been founded upon the relationship between technical factors and cultural factors. The contribution provided by Michele Guerra, an academic and professor of History of Cinema, confirms the words of Edgar Morin. «Nowadays, cinema is widely recognised as an art, and in my opinion, it is a tremendous polyphonic and polymorphous art that is capable of stimulating and integrating into itself the virtues of all the other arts: novel-writing, theatre, music, painting, scenography, photography. [...] it can be said that those who participate in the creation of a film are artisans, artists, who play an important role in the aesthetics of the film» (Morin, 2019). The work of the “cinematographic construction site” is driven by forces which, incorporating the status quo of the technical and material factors, lead to “an idea of imaginary metamorphosis” which reflects the aspirations of a society in its efforts to become contemporary. A concept of a heteronomous approach to “making” is also founded upon recognising the didactic value of the work, as emerges from Luigi Alini’s contribution on the figure of Vittorio Garatti – an intellectual first and architect second – whose pieces are the result of work that is as much immaterial as it is material, with an «experiential rather than mediatic» approach (Frampton, in Borsa and Carboni Maestri, 2018), as true architecture is expected to be. The heteronomy of architecture, much like that of other similar disciplines, is based on engagement on two fronts: an understanding of the relevant international scenarios and the definition of the project charter, with a view to conforming it so that it takes into account any changes, operates in continuity with and with an appreciation for history, and develops in harmony with the universality of the discipline and the teachings of its masters. Stimulating a dialogue between different cultural positions is a means to create the conditions for a degree of adherence to contemporaneity without compromising on a principle of historical continuity. In light of this, the contribution by Ferruccio Resta – the current Rector of the Politecnico di Milano – focuses on the varying cultural and intellectual positions that have animated the culture of the Politecnico over the years, representing a highly valuable heritage for the university. Nowadays, with the presence of certain indispensable premises such as sustainability and connectivity, technology seems to overwhelm the design process, outsourcing it to a sort of management of the engineering and component production aspects. Hence the need to reaffirm a “humanistic and human” dimension of the act of making, starting at the root by orienting the training processes in line with the words of historian and philosopher Yuval Noah Harari, who says: «Many pedagogical experts argue that schools should switch to teaching “the four Cs” – critical thinking, communication, collaboration, and creativity. More broadly, they believe, schools should downplay technical skills and emphasize general-purpose life skills. Most important of all will be the ability to deal with change, learn new things, and preserve your mental balance in unfamiliar situations». This need reopens the theme of the dualism between “art” and “discipline”, surpassing it in favour of a coexistence of terminology in that it is the quality of the design and the piece that define where it belongs. Reflecting on the foundations of the paths and tools employed in different disciplines – in light of the innovations that involve the project charter in terms not only of concepts, but also of instruments – means reflecting on the concept of “project culture”, understood as the ability to work through actions which combine different contributions, tackling complex problems by way of a conscious creative process. The ability to envisage the new – as is implicit in the etymology of the word “project” itself – and, at the same time, to interpret continuity in the sense of a coherent system of methods and values, is shared by the disciplines and skills brought together in the Dossier: dealing with culture, society, the city, the landscape and the environment all at once requires a multifaceted vision, an ability to read problems, but also a certain openmindedness towards opportunities, the management of complexities, control of the risks of drops in quality in service of concepts of efficiency based on numerical parameters and the standardisation of languages. A comparison of the various contributions and perspectives throws up a picture in which the importance of relationships, the search for what Eiffell defined «the secret laws of harmony», the disciplinary specificity of design as the ability to relate in order to «understand, criticise, transform» (Gregotti, 1981), the ability to distinguish that which is different by involving it in the transformation of design, all represent the foundations for the evolution of heteronomous disciplines in how they move beyond the notions of technique and context as passive referents which generate possibilities in line with the Rogersian reflection on pre-existing environmental elements as historical conditions for reference, critically taken on as determinants. Hence the validity of a “polytechnic” cultural approach that is not only capable of deploying tools and skills which can deal with the operating conditions to be found in a heteronomous context, but also of stimulating critical approaches oriented towards innovation and managing change with the perspective of a project as an opportunity – in the words of Franco Albini – for «experimentation and verification in relation to the progression of construction techniques, tools for investigation, knowledge in the various fields and in relation to the shifts in contemporary culture» (Albini, 1968). The need for a sense of humanism is strongly linked to the reintroduction of the concept of “beauty”, in its modern meaning, under which it shifts from a subjective value to a universal one. Hence the importance of the dialogue with disciplines that identify with the polytechnic mould – that is, one which has always been deeply attentive to the relationship between theory and practice, to the design of architecture as an action that is at once intellectual and technical. As such, starting from the assumption that «no theory can be pursued without hitting a wall that only practice can penetrate» (Deleuze and Foucault 1972; Deleuze, 2002; Foucault, 1977; Deleuze, 2007), it is now essential to promote the professional profiles of artists, musicians, philosophers, humanistic architects and so on who are capable of managing design as a synthesis of external factors, but also as an internal dialectic, as well as skills capable of creating culture understood as technical knowledge. Sometimes, faced with the difficulty of discerning an identity for disciplines, we attempt to draw a boundary that allows us to better understand their meaning and content. However, going on the points of view that have emerged in the Dossier, it seems more important than ever to «work on the boundaries of each field of knowledge», drawing upon a concept expressed by Salvatore Veca (Veca, 1979), making communication between fields a central value, interpreting relationships and connections, identifying the relational perspective as a fundamental aspect of the creative act. The position of architecture as an “art at the edge of the arts”1, as so often posited by Renzo Piano, allows for a reflection on its identity by placing it in a position that centralises rather than marginalises it. A concept of “edge” that touches upon the sociological viewpoint that distinguishes the “finite limit” (boundary) from the “area of interaction” (border) (Sennet, 2011; Sennet, 2018), in which the transformational yet constructive contact with the entities necessary for its realisation takes place. The heteronomy of architecture coincides with its “universality”, a concept that Alberto Campo Baeza (Campo Baeza, 2018) believes to represent the identity of architecture itself. Indeed, its dependence upon human life, the development of society, of its cultural growth, derives from a single and inalienable factor: its heteronomy, the necessary condition for a process as artistic as it is technical, tasked with expressing the values of a community over time and representing the “beautiful” rather than the “new”. A design practice based on – to borrow some concepts already expressed years ago by Edgar Morin – “contaminations that are necessary as well as possible”, on the contribution of “knowledge as an open system”, but above all, one aimed at working “against the continuities incapable of grasping the dynamics of change” (Morin, 1974), thus becomes an opportunity to develop a theory on the identity of the discipline itself, striking a balance between the technical and poetic spheres, but necessarily materialising in the finished work, lending substance to the «webs of intricate relationships that seek form» (Italo Calvino).

Dopo un'introduzione generale sul fenomeno della regolarizzazione attraverso rumore in un contesto degenere, la prima parte di questa tesi si concentra nello stabilire le stime di Schauder, un strumento analitico utile per dimostrare anche il carattere ben posto di equazioni differenziali stocastiche (EDS), per due classi di equazioni di Kolmogorov sotto una condizione di tipo Hörmander debole, i cui coefficienti giacciono in opportuni spazi di Hölder anisotropi con multi-indici di regolarità. La prima classe considera un sistema non lineare controllato da un operatore simmetrico ⍺-stabile che agisce solo su alcune componenti. Il nostro metodo di dimostrazione si basa su un approccio perturbativo basato su espansioni della parametrice progressiva tramite formule di tipo Duhamel. A causa delle scarse proprietà regolarizzanti date dal contesto degenere, sfruttiamo anche alcuni controlli sulle norme di Besov, per trattare la perturbazione non lineare. Come estensione del primo modello, presentiamo anche delle stime di Schauder associate a un operatore di Ornstein-Uhlenbeck degenere guidato da una classe più ampia di operatori di tipo quasi-stabile, come quello stabile relativistico o quello di Lamperti. La dimostrazione di questo risultato si basa invece su un'analisi precisa del comportamento del semigruppo di Markov corrispondente tra spazi di Hölder anisotropici e alcune tecniche di interpolazione. Sfruttando un approccio della parametrice retrograda, la seconda parte di questa tesi cerca di stabilire il carattere ben posto in senso debole per una catena degenere di EDS guidate dalla stessa classe di processi quasi-stabili, sotto le assunzioni di regolarità di Hölder minime per i coefficienti. Come corollario del nostro metodo, presentiamo anche stime di tipo Krylov di interesse indipendente per il processo canonico sottostante. Infine, sottolineiamo attraverso opportuni controesempi che esiste effettivamente una soglia (quasi) ottimale sugli esponenti di regolarità che garantiscono il carattere ben posto debole per l'EDS. In relazione ad alcune applicazioni meccaniche per delle dinamiche cinetiche con attrito, concludiamo studiando la stabilità delle perturbazioni del secondo ordine per operatori degeneri di Kolmogorov nelle norme Lp e Hölder.
After a general introduction about the regularization by noise phenomenon in the degenerate setting, the first part of this thesis focuses at establishing the Schauder estimates, a useful analytical tool to prove also the well-posedness of stochastic differential equations (SDEs), for two different classes of Kolmogorov equations under a weak Hörmander-like condition, whose coefficients lie in suitable anisotropic Hölder spaces with multi-indices of regularity. The first class considers a nonlinear system controlled by a symmetric ⍺-stable operator acting only on some components. Our method of proof relies on a perturbative approach based on forward parametrix expansions through Duhamel-type formulas. Due to the low regularizing properties given by the degenerate setting, we also exploit some controls on Besov norms, in order to deal with the non-linear perturbation. As an extension of the first one, we also present Schauder estimates associated with a degenerate Ornstein-Uhlenbeck operator driven by a larger class of ⍺-stable-like operators, like the relativistic or the Lamperti stable one. The proof of this result relies instead on a precise analysis of the behaviour of the associated Markov semigroup between anisotropic Hölder spaces and some interpolation techniques. Exploiting a backward parametrix approach, the second part of this thesis aims at establishing the well-posedness in a weak sense of a degenerate chain of SDEs driven by the same class of ⍺-stable-like processes, under the assumptions of the minimal Hölder regularity on the coefficients. As a by-product of our method, we also present Krylov-type estimates of independent interest for the associated canonical process. Finally, we emphasize through suitable counter-examples that there exists indeed an (almost) sharp threshold on the regularity exponents ensuring the weak well-posedness for the SDE. In connection with some mechanical applications for kinetic dynamics with friction, we conclude by investigating the stability of second-order perturbations for degenerate Kolmogorov operators in Lp and Hölder norms.