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This study presents a novel method for manufacturing microfluidic paper–fabric hybrid analytical devices (μPFADs), which play a vital role in conducting diagnostic tests at the point of care (POC), especially in resource-limited environments. By circumventing the need for complex machinery or highly skilled operators, our method presents a practical solution for scaling up these POC devices. The approach involves the utilization of a folded paper structure featuring a specific pattern like a circular well or liner microchannel on either side of the fold as a mirror image, followed by inserting a piece of fabric in between the paper fold, thereby creating a sandwich-like structure. Subsequently, a PDMS (polydimethylsiloxane) elastomer with base and curing agents in a 10:1 ratio would be coated over the entire top paper and allowed to settle, enabling the penetration of PDMS down to the bottom paper through the sandwiched fabric. When sufficient PDMS penetration is achieved through visual changes on the back side of the paper, the sandwiched assembly is heated for polymerization of the PDMS. An embedded fabric-based POC device is obtained within the paper whose structure is defined by the designs on the folded paper itself. This micro paper–fabric hybrid analytical device (μPFAD) offers several noteworthy advantages as it boasts rapid fabrication times and is cost-effective, without the need for any printing machines, thereby further enhancing its suitability for no- or low-resource environments. Experimental studies with these μPFADs were conducted for the colorimetric detection of iodine, whose deficiency is a leading cause of thyroid disorders, particularly hypothyroidism. Here, starch acts as the chromogenic agent, which forms a blue-colored complex that shifts the color from purple to deep blue–black with increasing iodine concentration. The initial experimental results reveal contrasting color changes for varying levels of iodine using the proposed μPFADs, which would be useful for the early diagnosis and management of thyroid disorders. [ABSTRACT FROM AUTHOR]

This paper aims at re-evaluating two of Hungarian artist Dóra Mauer's films, the video work PROPORTIONS (1979) and the 16mm film TIMING (1973/80). Both films follow a rigid structure. In PROPORTIONS, Maurer uses a paper roll to compare her own body measures repeatedly; in TIMING, she repeatedly folds a white linen to compare the rhythm of her arm movements. Through her use of paper and the gesture of folding, the two films can be read as references to the very origin of the term format , as coined in early letterpress printing. When the notion of format is understood as a determination of a ratio and, as such, as an indexical reference to given social relationships (Summers, 2003), these films unfold sociocultural and political meanings. The present paper traces this spectrum of meaning through the pointed inclusion of historical discourses surrounding early motion studies, the art scene in socialist Hungary in the 1970s, and early time experiments before the advent of precision clocks. [ABSTRACT FROM AUTHOR]

The grey silverfish Ctenolepisma longicaudatum is a new and serious pest spreading rapidly across Europe. Compared to the silverfish Lepisma saccharinum, it does not depend on relative humidity above 70% and thrives also in new museum buildings, modern storage depositories, apartments, and office buildings. Especially collections of graphic art, modern art on paper, photographs, but also archives and libraries are increasingly affected by this pest. Damage of paper objects has been reported by different authors and institutions across Europe. As these animals live in inaccessible cracks and crevices inside the buildings, we investigated the spread of microorganisms on living grey silverfish, to show a potential additional threat posed by this pest. In 8 locations in Austria living animals were collected with traps and placed for 10 min on agar plates which were incubated for 2 weeks. After incubation of 50 agar plates, between 2 and 20 colonies of fungi were growing on each plate. The most dominant fungal genera were Cladosporium (Cladosporium cladosporioides clade) and Penicillium (Penicillium glabrum, Penicillium decumbens); also, species of the genera Aspergillus, Alternaria, Botrytis, Bartalinia, Byssochlamis, Chaetomium and Mycothypha were found. The diversity of fungi reflects the common fungal community of museums and archives. The spores and mycelial fragments of the fungi are obviously travelling on the legs and bodies of the silverfish. [ABSTRACT FROM AUTHOR]

In June 2019, the Faculty of Arts of the University in Ljubljana and the Archives of the Republic of Slovenia organized an international scientific symposium "Works of Art on Parchment and Paper". Proceedings with 27 peer-reviewed articles were published in November 2019. Experts from the field of natural and humanistic sciences presented their results related to techniques of monuments' creation and their place in the time of creation; they presented relationships among artists and their audiences and presented problems of preservation, conservation, restoration and interpretation of art works on parchment and paper. The article gives a brief overview of the symposium and then focuses on the interconnection among humanistic and natural sciences and reflects the author's thoughts on the meaning and wholeness of research, knowledge collection and achievement of scientific goals. [ABSTRACT FROM AUTHOR]

In the paper the folding quality in the printing house "BALTO" is investigated. The concept of quality, paper folding process, combined folding machine parameters and printing papers are described. In the paper the percent of folding defects is determined, the spoilage dependence on paper characteristics, folding machine settings and other factors are investigated. Results were presented as histograms and were analyzed using statistical methods. [ABSTRACT FROM AUTHOR]

Abstract: The Szeged index extends the Wiener index for cyclic graphs by counting the number of vertices on both sides of each edge and sum these counts. Klavzar et al. [S. Klavzar, A. Rajapakse, I. Gutman, The Szeged and the Wiener index of graphs, Appl. Math. Lett. 9 (5) (1996) 45–49] provided an exact formula for computing Szeged index of product of graphs. In this paper, we apply a matrix method to obtain exact formulae for computing the Szeged index of join and composition of graphs. The join and composition of the vertex PI index of graphs are also computed. [Copyright &y& Elsevier]

Abstract: A tree which has exactly one vertex of degree greater than two is said to be starlike. In spite of seemingly simple structure of these trees, not much is known about their spectral properties. In this paper, we introduce a generalization of the notion of cospectrality called -cospectrality which turns out to be useful in constructing cospectral graphs. Based on this, we construct cospectral mates for some starlike trees. We also present a set of necessary and sufficient conditions for divisibility of the characteristic polynomial of a starlike tree by the characteristic polynomial of a path. [Copyright &y& Elsevier]

Abstract  Multiobjective optimization methodology for the development of the papermaking process is considered. The aim is to find efficient and reliable solution procedures for the process line model consisting of sequential unit-process models; some of them based on physics, whereas others on experimental data. By the consequence of modeling procedures, nonphysical states or inherited from modeling data in statistical case, the unit-process models may suffer from undesired unreliability. To control the uncertainty resulting from the unit-process models, a new multiobjective optimization approach is introduced where both the papermaking targets as well as the uncertainty related unit-process models are simultaneously taken into account. We illustrate the solution process by numerical examples related to the quality of the produced paper. [ABSTRACT FROM AUTHOR]

Abstract: This paper sets forth three mismatch properties, strictly ordered in strength, about sewings of crumpled n-cubes. The strongest is a sufficient but not a necessary condition for a sewing to yield , and the weakest, a necessary but not sufficient one. We show that when both crumpled cubes satisfies the Disjoint Disks Property, then the weakest property implies the sewing yields , and we also show that the intermediate property leads to the same conclusion when just one of the crumpled cubes possesses the Disjoint Disks Property. In addition, we develop examples that confirm sharpness of the relevant Disjoint Disks conditions. [Copyright &y& Elsevier]

Abstract: In this paper, we give some characterizations of the integral and Carleson type measure both associated with higher radial derivative for holomorphic functions of and spaces in the unit ball of . As applications, some sharp forms of the relations between Dirichlet type spaces and spaces are shown by means of higher radial derivative, Carleson type measure and constructive methods for the cases of determinism and randomization, respectively. [Copyright &y& Elsevier]

Abstract: In this paper, we study a boundary feedback system of a class of nonuniform undamped Timoshenko beam with both ends free. We give some sufficient conditions and some necessary conditions for the system to have exponential stability. Our method is based on the operator semigroup technique, the multiplier technique, and the contradiction argument of the frequency domain method. [Copyright &y& Elsevier]

Abstract: This paper develops the notion of implicit Lagrangian systems and presents some of their basic properties in the context of Dirac structures. This setting includes degenerate Lagrangian systems and systems with both holonomic and nonholonomic constraints, as well as networks of Lagrangian mechanical systems. The definition of implicit Lagrangian systems with a configuration space makes use of Dirac structures on that are induced from a constraint distribution on as well as natural symplectomorphisms between the spaces , , and . Two illustrative examples are presented; the first is a nonholonomic system, namely a vertical disk rolling on a plane, and the second is an L–C circuit, a degenerate Lagrangian system with holonomic constraints. [Copyright &y& Elsevier]

The aim of this paper is to describe and analyze the discourse utilized by President George Bush after the terrorist attacks on September 11, 2001. I carried out the analysis of the discourse strategies used by the main actors involved in justifying of the war on their foes. As a method for analyzing the discourse I relied on frame analysis. Framing involves selecting certain aspects of the reality perceived into a text in order to endorse definitions of the protagonist, antagonist and the conflict and then to propose some alternatives for the solution of said conflict. [ABSTRACT FROM AUTHOR]

This paper is a continuation of the work done in [1]. We define Dirac-Nijenhuis structures (DN structures) on Lie bialgebroids, a generalization of the notion of Dirac-Nijenhuis structures on manifolds given in [1]. However, the problems we are going to deal with are more complex than the ones in [1]. The necessary and sufficient conditions for a structure to be a DN structure on a Lie bialgebroid as well as several examples of these structures are given. At the end of the paper we discuss the fundamental sections of DN structures. [Copyright &y& Elsevier]

We model the folding of ordinary paper via piecewise isometries R2→R3. The collection of crease lines and vertices in the unfolded paper is called the crease pattern. Our results generalize the previously known necessity conditions from the more restrictive case of folding paper flat (into R2); if the crease pattern is foldable, then the product (in a non-intuitive order) of the associated rotational matrices is the identity matrix. This condition holds locally in a multiple vertex crease pattern and can be adapted to a global condition. Sufficiency conditions are significantly harder, and are not known except in the two-dimensional single-vertex case. [Copyright &y& Elsevier]

The long-term effect of gamma irradiation on paper was studied. Three types of paper (pure rag, mixed rag and mechanically prepared woodpulp) were subjected to three treatments: gamma irradiation, accelerated dry aging, and radiation followed by aging. The effects of these treatments on the physical properties of the paper samples were assessed by measuring alterations in mechanical strength as determined by changes in folding endurance and tear resistance when compared to the untreated control samples. It was found that gamma irradiation caused a decrease in the mechanical strength of the papers similar to that resulting from accelerated dry aging. A synergistic effect was found when both irradiation and accelerated aging were performed on the paper samples, demonstrated by an even greater decrease in both fold endurance and tear resistance than that resulting from either gamma irradiation or accelerated dry aging alone. [ABSTRACT FROM AUTHOR]

The author reflects on writing academic journals. He states that writing and publishing an academic paper is not an easy job. He presents guidelines for authors to create various types of articles for publication which include review articles, and case report articles. He also mentions about organizing original article.

The article presents the author's views on a mathematical problem as part of a paper-folding activity focusing on perimeter for secondary school students. He states that solving a problem successfully is intellectually gratifying and is a learning opportunity. He discusses the solution to the mathematical problem which involves a paper strip with a perimeter of 22 inches.

The article focuses on teaching children paper art. Each children should have their own pair of scissors. The size of paper needed is 4 by 6 inches. Various styles of paper folding are illustrated and described. The teacher should demonstrate how to put a little mucilage in the middle of one square.

The article explores on the simple procedure for processing event recorder data. The strip chart device called event recorder reads the state of an electrical switch with reference to time used in various studies is said to require a long to process the gathered data. According to the author, the usual procedure uses scissors to cut the strip charts into segments representing the desired time base which is tedious. He suggests the use of a stapler and paper cutter as an alternative for collecting the gathered data.