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Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 663
Tomasz Garbowski ◽  
Anna Knitter-Piątkowska

Bending stiffness (BS) is one of the two most important mechanical parameters of corrugated board. The second is edge crush resistance (ECT). Both are used in many analytical formulas to assess the load capacity of corrugated cardboard packaging. Therefore, the correct determination of bending stiffness is crucial in the design of corrugated board structures. This paper focuses on the analytical determination of BS based on the known parameters of the constituent papers and the geometry of the corrugated layers. The work analyzes in detail the dependence of the bending stiffness of an asymmetric, five-layer corrugated cardboard on the sample arrangement. A specimen bent so that the layers on the lower wave side are compressed has approximately 10% higher stiffness value. This is due to imperfections, which are particularly important in the case of compression of very thin liners. The study showed that imperfection at the level of a few microns causes noticeable drops in bending stiffness. The method has also been validated by means of experimental data from the literature and simple numerical finite element model (FEM). The obtained compliance of the computational model with the experimental model is very satisfactory. The work also included a critical discussion of the already published data and observations of other scientists in the field.

Hemato ◽  
2022 ◽  
Vol 3 (1) ◽  
pp. 47-62
Francesca Lavatelli

The deposition of amyloid light chains (LCs) in target sites translates into tissue damage and organ dysfunction. Clinical and experimental advances have cast new light on the pathophysiology of damage in AL amyloidosis. The currently accepted view is that, besides the alterations caused by fibrillar deposits in the extracellular space, direct proteotoxicity exerted by prefibrillar LC species is an important pathogenic factor. As our knowledge on the pathological species and altered cellular pathways grows, novel potential therapeutic strategies to prevent or reduce damage can be rationally explored. Complementing chemotherapy with approaches aimed at disrupting the deposited fibrils and stabilizing prefibrillar amyloidogenic LC may allow halting or even reverting damage in target sites. This review recapitulates the current knowledge and the most recent acquisitions regarding the mechanisms of organ damage in AL amyloidosis, with special emphasis on the heart, and will provide a critical discussion on possible novel treatment targets.

Iver Brevik ◽  
Boris Shapiro

Abstract The Casimir-Lifshitz force acts between neutral material bodies and is due to the fluctuations (around zero) of the electrical polarizations of the bodies. This force is a macroscopic manifestation of the van der Waals forces between atoms and molecules. In addition to being of fundamental interest, the Casimir-Lifshitz force plays an important role in surface physics, nanotechnology and biophysics. There are two different approaches in the theory of this force. One is centered on the fluctuations inside the bodies, as the source of the fluctuational electromagnetic fields and forces. The second approach is based on finding the eigenmodes of the field, while the material bodies are assumed to be passive and non-fluctuating. In spite of the fact that both approaches have a long history, there are still some misconceptions in the literature. In particular, there are claims that (hypothetical) materials with a strictly real dielectric function $\varepsilon(\omega)$ can give rise to fluctuational Casimir-Lifshitz forces. We review and compare the two approaches, using the simple example of the force in the absence of retardation. We point out that also in the second (the "field-oriented") approach one cannot avoid introducing an infinitesimal imaginary part into the dielectric function, i.e. introducing some dissipation. Furthermore, we emphasize that the requirement of analyticity of $ \varepsilon(\omega)$ in the upper half of the complex $\omega$ plane is not the only one for a viable dielectric function. There are other requirements as well. In particular, models that use a strictly real $\varepsilon(\omega)$ (for all real positive $\omega)$ are inadmissible and lead to various contradictions and inconsistencies. Specifically, we present a critical discussion of the "dissipation-less plasma model". Our emphasis is not on the most recent developments in the field but on some conceptual, not fully resolved issues.

Mara Heckmann ◽  
Gerald Klanert ◽  
Georg Sandner ◽  
Peter Lanzerstorfer ◽  
Manfred Auer ◽  

Abstract Postprandial insulin-stimulated glucose uptake into target tissue is crucial for the maintenance of normal blood glucose homeostasis. This step is rate-limited by the number of facilitative glucose transporters type 4 (GLUT4) present in the plasma membrane. Since insulin resistance and impaired GLUT4 translocation are associated with the development of metabolic disorders such as type 2 diabetes, this transporter has become an important target of antidiabetic drug research. The application of screening approaches that are based on the analysis of GLUT4 translocation to the plasma membrane to identify substances with insulinomimetic properties has gained global research interest in recent years. Here, we review methods that have been implemented to quantitate the translocation of GLUT4 to the plasma membrane. These methods can be broadly divided into two sections: microscopy-based technologies (e.g., immunoelectron, confocal or total internal reflection fluorescence microscopy) and biochemical and spectrometric approaches (e.g., membrane fractionation, photoaffinity labeling or flow cytometry). In this review, we discuss the most relevant approaches applied to GLUT4 thus far, highlighting the advantages and disadvantages of these approaches, and we provide a critical discussion and outlook into new methodological opportunities.

Nanomaterials ◽  
2022 ◽  
Vol 12 (2) ◽  
pp. 207
Toma Fistos ◽  
Irina Fierascu ◽  
Radu Claudiu Fierascu

Cultural heritage (CH) represents human identity and evidence of the existence and activities that people have left over time. In response to the action of aggressive degrading factors, different materials have been developed and used to protect cultural heritage artifacts. The discovery of optimal materials for this purpose also raises several problems, mainly related to their compatibility with the support material, the most important aspect being that they must preserve their aesthetic characteristics. In this context, the present review paper aims to provide a critical discussion about the possibilities of using different inorganic nanomaterials and recipes for the conservation of cultural heritage objects of organic nature (such as paper, wood, and other support materials). In addition, also are covered different aspect concerning protection mechanisms and application methods as well as future perspectives in this area.

2022 ◽  
pp. 019145372110615
Per Jepsen

The article entails a critical discussion of the book Capitalism, Alienation and Critique by Asger Sørensen. Like Sørensen’s book, it stresses the importance of the first generation of critical theory – especially Horkheimer and Adorno – although Sørensen is at the same time critized for neglecting the insights of Horkheimer and Adornos work from the mid-1940s and onwards. In arguing for the actuality of especially the late Horkheimer, the article emphasizes the following topics: (1) The problems of education and ‘Bildung’, (2) The historical transformation of the critique of Capitalism after the Second World War and (3) The drawbacks of classical humanism when it comes to grasping the current political and ecological crisis.

2022 ◽  
Vol 10 (1) ◽  
pp. 6
Matthias Epple ◽  
Joachim Enax ◽  
Frederic Meyer

Dental erosion is a common problem in dentistry. It is defined as the loss of tooth mineral by the attack of acids that do not result from caries. From a physico-chemical point of view, the nature of the corroding acids only plays a minor role. A protective effect of fluorides, to prevent caries and dental erosion, is frequently claimed in the literature. The proposed modes of action of fluorides include, for example, the formation of an acid-resistant fluoride-rich surface layer and a fluoride-induced surface hardening of the tooth surface. We performed a comprehensive literature study on the available data on the interaction between fluoride and tooth surfaces (e.g., by toothpastes or mouthwashes). These data are discussed in the light of general chemical considerations on fluoride incorporation and the acid solubility of teeth. The analytical techniques available to address this question are presented and discussed with respect to their capabilities. In summary, the amount of fluoride that is incorporated into teeth is very low (a few µg mm−2), and is unlikely to protect a tooth against an attack by acids, be it from acidic agents (erosion) or from acid-producing cariogenic bacteria.

2022 ◽  
Gunnar Sivertsen

The paper describes the full range of publishing and its purposes in the social sciences – from scholarly publishing via professional communication to societal interaction in public media – and how it is represented in five different contexts for research evaluation and funding. The five contexts are: applications for external project funding, applications for positions or promotions, indicator-based institutional funding systems, summative organizational evaluation systems, and formative organizational evaluation systems. The chapter provides a critical discussion of how publications from the social sciences may be filtered out or placed in predetermined hierarchies in these evaluation and funding contexts, and also of how the evaluation and funding procedures can be improved to appropriately represent social science research and publishing.

2022 ◽  
Vol 5 (1) ◽  
pp. 70-89
Lakshmi Sigurdsson ◽  
Kirsten M. Andersen

The Preamble of the Universal Declaration of Human Rights (UDHR) states that ‘disregard and contempt for human rights have resulted in barbarous acts which have outraged the conscience of mankind’. From this point of departure, we argue that philosophical, political, and religious reflections on core concepts such as conscience, freedom, equality, dignity, justice, and peace can help to create an appropriate balance between a normative framework and a non-affirmative approach to human rights education. Teacher students can benefit from philosophical reflection, critical thinking, and individual judgement, as this will enhance the authoritativeness and self-determination of both teachers and learners. In terms of didactics, we consider the potentials of a concept-based approach inspired by the political philosophy of Hannah Arendt and her critical discussion of the perplexities of the rights of man.

2022 ◽  
pp. 22-44
Feras Ali Qawasmeh

Public policy is classified as a major field in public administration. Therefore, to understand the context of public policy as a field, it is essential to explore its root developments in public administration from epistemological and chronological perspectives. This chapter is a review study referring to main scholarly works including books, academic articles, and studies. The chapter first helps researchers and students in comprehending the evolution of public administration in its four main stages including classical public administration, new public administration, new public management, and new public governance. Second, the chapter presents a general overview of the evolution of the public policy field with particular attention paid to the concepts of Harold Lasswell who is seen as the father of public policy. The chapter then discusses different definitions of public policy. Various classifications of public policy are also investigated. The chapter ends with a critical discussion of the stages model (heuristics).

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