Linear stability analysis of capillary instabilities for concentric cylindrical shells

Motivated by complex multi-fluid geometries currently being explored in fibre-device manufacturing, we study capillary instabilities in concentric cylindrical flows of $N$ fluids with arbitrary viscosities, thicknesses, densities, and surface tensions in both the Stokes regime and for the full Navier--Stokes problem. Generalizing previous work by Tomotika (N=2), Stone & Brenner (N=3, equal viscosities) and others, we present a full linear stability analysis of the growth modes and rates, reducing the system to a linear generalized eigenproblem in the Stokes case. Furthermore, we demonstrate by Plateau-style geometrical arguments that only axisymmetric instabilities need be considered. We show that the N=3 case is already sufficient to obtain several interesting phenomena: limiting cases of thin shells or low shell viscosity that reduce to N=2 problems, and a system with competing breakup processes at very different length scales. The latter is demonstrated with full 3-dimensional Stokes-flow simulations. Many $N > 3$ cases remain to be explored, and as a first step we discuss two illustrative $N \to \infty$ cases, an alternating-layer structure and a geometry with a continuously varying viscosity

The socratic dialogue as a ritual of emotional purification

Abstract In the present paper, the role that emotions play in Socratic self-care, as it can be reconstructed from Plato's dialogues, is investigated and explored. In highlighting the fundamental role that emotions play in such a care, which is not mere repair of a fault (reparative care), but an active and constant attending to self- and others' improvement, it is emphasized how the Socratic care that is enacted in the Selected Dialogues exhibits marked religious qualities, which make Socrates a kind of priestly and demonic figure, as the reader can infer in particular from the two chapters devoted to the Critique and the Apology, respectively. The intent underlying this focus on the religious and especially initiatory aspects of Socratic care in the Platonic dialogues is, as explained at the beginning of the introduction to this work, to deepen the link between the emotional aspect of self-care, explored in depth by Professor L. Napolitano, and my personal interest in the relationship between philosophy and religion. In the present work this link has been found in the theme of 'aporia; this is interpreted in the introduction and in the following chapters as ritual death, that is, as an 'experience in which the initiate (in this case Socrates' interlocutor) witnesses his own death, that is, the disappearance of the firm attachment to his unreflective opinions. It follows that 'aporia is a positive element of self-care, since this ritual death makes it possible, if it is accepted and not rejected, to get rid of those obstacles from within that prevent one from looking forward to one's own improvement and the pursuit of happiness. Aporia is not only a logical impasse, but also an emotionally very dense moment; it therefore holds together the two fundamental components of this work, the focus on emotions in the Socratic dialogue and the focus on the initiatory aspects with which Plato cloaks this dialogue. Plato alludes to these initiatory aspects from time to time in the selected dialogues by appropriating now from Coribantism (Euthydemus), now from Orphism (Phaedo), now even from the rituals of transition from one age to another (the ephebia, as in the case of the Alcibiades); all these disparate experiences have in common the idea of a ritual death, a liminal phase between one life (the one about to leave) and the new one (about to embark on). In the Socratic dialogue enacted in Plato's works, precisely this initiatory death (the aporia) is II achieved; if the interlocutor accepts it, he or she will progress on the path of self care; if he or she is afraid or annoyed by it, he or she will derive no benefit. The introduction outlines the assumptions on which the following analysis are based: the first is the ritual and initiatory nature of refutation and the characterization of aporia as an emotionally connoted moment; the second, based on the analysis of the first book of the Republic, is the relational nature of caring and thus of the good that caring/caretaking pursues; therefore, one who cares for others necessarily also cares for himself. The intertwining of the ritual and emotional aspects, as well as the communal and relational nature of the good pursued by Socratic caring, is explored throughout the introduction and, more importantly, eight chapters, devoted to Euthydemus, Charmides, Alcibiades I, Lysis, Euthyphro, Apology, Critique, and Phaedo, respectively. In the introduction to the thesis, the reason for the choice of these dialogues is explained and what are the relationships between them in this work. In the conclusion, the scientific and especially moral reasons for the importance of emphasizing the role of emotions in Plato's Socrates and the ritual aspects of it are made clea

La proyección estereiográfica como recurso para el desarrollo de la percepción espacial y el aprendizaje significativo en Geología Estructural

La rama de la Geología Estructural estudia las estructuras de las rocas a todas las escalas, caracterizando los cálculos geométricos, movimientos y esfuerzos que son los responsables de los desplazamientos y deformaciones de masas rocosas. Debido a la naturaleza tridimensional de los estudios típicos de Geología Estructural, estos requieren una habilidad espacial bien desarrollada. La proyección estereográfica es un método que permite manejar e interpretar estructuras geológicas tridimensionales en una superficie bidimensional. En este trabajo se ha realizado una investigación cualitativa, con un caso de estudio y un grupo específico de alumnos de grado y posgrado en Geología, de la Universidad Estatal de Campinas, en Brasil. Se propusieron varios ejercicios prácticos, en talleres de proyección estereográfica, para facilitar el aprendizaje significativo de una manera sencilla y eficaz, así como mejorar la habilidad de visualización tridimensional. Los resultados muestran que la asociación de actividades manuales y computacionales ayuda a perfeccionar la percepción espacial, aunque muchos estudiantes tienden a realizar las tareas de manera mecánica. Una de las conclusiones es que la habilidad de visualización tridimensional es esencial para el desarrollo del aprendizaje significativ

Worldsheet scattering for string mirror models

openThe quantisation of string theories on curved backgrounds is a notoriously difficult task. One approach that is proving very powerful when string non-linear sigma model is integrable is to bootstrap a factorised S matrix on the two-dimensional string worldsheet. The computation of the finite-volume spectrum then requires to introduce a Wick-rotated worldsheet model, the so-called mirror model. This is quite non-trivial if the original worldsheet theory is not relativistic. This thesis will perturbatively compute the two-particle into two-particle scattering processes and some production processes for the "mirror" of a worldsheet model.The quantisation of string theories on curved backgrounds is a notoriously difficult task. One approach that is proving very powerful when string non-linear sigma model is integrable is to bootstrap a factorised S matrix on the two-dimensional string worldsheet. The computation of the finite-volume spectrum then requires to introduce a Wick-rotated worldsheet model, the so-called mirror model. This is quite non-trivial if the original worldsheet theory is not relativistic. This thesis will perturbatively compute the two-particle into two-particle scattering processes and some production processes for the "mirror" of a worldsheet model

Challenges of Information Literacy in Myanmar

Infographic on issues related to information literacy in Myanmarhttps://digitalcommons.bard.edu/digitalliteracy/1001/thumbnail.jp

Histological Evaluation of the Cryo-Destruction of the Zona Glomerulosa (Outermost Layer) of the Adrenal Cortex

The outer portion, or cortex, of the adrenal gland produces three hormones, two of which are highly critical to normal function of the body. The cortex itself is divided into three layers, each responsible for a certain hormone synthesis. The outermost layer (zona glomerulosa) produces aldosterone, a hormone involved in the regulation of body sodium, blood volume, and blood pressure. The middle layer produces co rticosterone, a hormone that is active in a variety of biological functions, and necessary for life. Due to its effects on blood volume, aldosterone has been implicated in the development of hypertension, or high blood pressure. Aldosterone has been studied through the use of receptor blocking agents, which are associated with undesirable side effects, and complete adrenalectomy (removal of both adrenal glands), which eliminates both aldosterone and corticosterone. The overall objective of the current study is to produce a surgically induced low aldosterone rat model, with functioning lower adrenal layers, by cryo- destruction of only the zona glomerulosa. The purpose of the present study was to perfect histological techniques for fixation, sectioning and staining of the adrenal glands, and to evaluate the success of the cryo-destruction. Adrenal glands were removed from rats 2, 4, and 8 weeks after cryo-destruction of the left adrenal zona glomerulosa. Glands were fixed in paraffin, sectioned, stained, and viewed under a microscope. Percent destruction of the outer layer of the adrenal cortex was estimated. Results: Techniques for fixing, sectioning, and staining of the adrenals glands was perfected by trial and error. The percent of the zona glomerulosa successfully destroyed by the cryo-treatment was highly variable between rats

Problems in the Implementation of Regional Regulations in Lampung Province as A Result of the Initiative Proposal of the Regional Legislative Council

This study aims to identify and explain the problems surrounding the implementation of Regional Regulations initiated by the Lampung Provincial House of Representatives (DPRD), particularly in terms of their effectiveness in supporting community welfare. Using a normative legal research method with a statute and theoretical approach, this study analyzed 12 Regional Regulations issued between 2015 and 2023 through content analysis of legal texts and supporting documents. The findings indicate two major issues. First, the absence of follow-up regulations in the form of Governor Regulations creates a legal vacuum, which hinders Regional Apparatus Organizations from operationalizing the Local regulation. Second, there is a fundamental disconnect between the legislative focus of the DPRD which emphasizes accommodating community aspirations and the executive priorities of the Regional Government, which are more programmatic and budget-oriented. As a result, DPRD-initiated Local regulation are often not integrated into regional development planning and remain unimplemented. This study recommends strengthening coordination mechanisms between the DPRD and the Regional Government during the legislative planning stage, as well as mandating a time-bound issuance of implementing regulations to ensure effective enforcement of regional laws

Stemness and Immunological Features of Thyroid Cancer Cells

Cancer stem cells (CSCs) can initiate and maintain tumours and may drive metastasis, recurrence and resistance to anti-neoplastic therapies. Recent evidence suggests that CSCs possess immunomodulatory capabilities that may enable them to evade host anti-cancer immunity to promote tumorigenicity. CSC immunological functions include evasion from immune clearance, induction of clonal anergy or deletion, and activation of regulatory immune cells. We recently identified Interleukin-8 as a crucial factor that sustains the stemness features of thyroid cancer (TC) cells through the induction, among the others, of OCT4 and SOX2 transcription factors. We generated OCT4/SOX2 overexpressing TC cells and analysed their stemness and immunomodulatory properties. We confirmed that TC cell lines overexpressing OCT4/SOX2 showed, compared to control cells, an increase in stemness features. Accordingly, OCT4/SOX2 TC cells displayed increased tumour incidence and growth when injected at limiting number in mice compared to parental cells. Negative regulators of the immune system, including Programmed cell Death-Ligands 1 and 2 (PD-L1/PD-L2) and the enzyme Indoleamine 2,3-dioxygenase (IDO) are often “hijacked” by tumours to restrain the ability of the immune system to mount an effective anti-tumor response. Here, we show that OCT4/SOX2 expressing TC cells display increased PD1, PD-L1/2 and IDO expression both at mRNA and protein levels with respect to parental cells. Consistently, TC cells overexpressing OCT4 and SOX2, when co-cultured with lymphoid cells, caused a reduction of lymphocyte vitality compared to control cells. Thus, OCT4 and SOX2 are not only key regulators of stemness features but also of immunomodulatory properties of TC cells

Maker: the return of the builders. A possible digital transition for Architecture

This contribution attempts to answer the following question: how will the digital revolution affect architecture in the near future? To try to formulate a convincing answer, only very faint signals that come from courageous experiments are available, a result mainly of research work rather than market-proposed stimuli. A handful of researchers in a select number of Universities, armed with extraordinary digital skills and maker-type instrumentation, are creating new experimental constructions in which highly complex design is combined with extremely simple construction, which do not require the manufacturing skills and expensive equipment that populate traditional construction sites. By establishing these lines of development, it would be possible to bring architecture close to the people and restore a central role for the designer in the making of buildings

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