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In this study, new synthesis strategies for poly (vinyl alcohol) (PVA) functionalized with azidation (Az) and alkynation (Alk) were carried out for surface functionality modification. These two functionalization routes utilize azide and alkyne groups, respectively, and offer simple way to enhance the PVA crosslinking capabilities toward producing new functional polymer-based materials. The Az functionalized PVA was prepared in two steps and denoted by PVA-Az, while Alk functionalized PVA was prepared in one step to produce PVA-Alk. Surfaces modification of PVA by using Az and Alk functional groups was confirmed by spectral analysis (Fourier transform infrared and [sup.13]C-NMR). Results showed that Alk prompted excellent chemical modifications on the surface of PVA while the thermal stability was enhanced by functionalizing the Az and Alk into PVA. Furthermore, X-ray photoelectron spectroscopy investigations showed a successful functionalization and new functional groups addition to PVA surface. Scanning electron microscope images were used to analyze the surface morphology of PVA by incorporating the Az and Alk groups, which indicated rougher surfaces compared to that of PVA backbone. In terms of efficiency and simplicity, the techniques used in this study appear to be entirely satisfactory. KEYWORDS alkyne, azide, click-chemistry, poly (vinyl alcohol), polymer functionalization, surface modification, orcid.org/0000-0002-23106620 orcid.org/0000-0002-9194719X 1 | INTRODUCTION Generally, polymers are classified into two main groups, natural and synthetic polymers. One of the most important subclasses within natural and synthetic polymers is biodegradable [...]

Computer simulation (CS) and thought experiments (TE) seem to produce knowledge about the world without intervening in the world. This has called for a comparison between the two methods. However, Chandrasekharan et al. (2013 (See CR16)) argue that the nature of contemporary science is too complex for using TEs. They suggest CS as the tool for contemporary sciences and conclude that it will replace TEs. In this paper, by discussing a few TEs from the history of science, I show that the replacement thesis about TE is a failure. The paper is divided into three sections. The first section discusses the arguments of Chandrasekharan et al. (2013 (See CR16)) and demonstrates the three distinct aspects of the replacement thesis. The second section examines the argument against TE and shows that they are inadequate to prove the withering of TE from science. The third section discusses Albert Einstein's Magnet and Conductor TE and demonstrates that replacing such TE with CS yield no advantage., Author(s): N. K. Shinod [sup.1] Author Affiliations: (1) grid.18048.35, 0000 0000 9951 5557, Department of Philosophy, University of Hyderabad, , Gachibowli, 500046, Hyderabad, India Introduction Though thought experiments (TEs) and [...]

Complementarity can be considered as the weirdest idea associated with quantum mechanics. For Bohr, Complementarity is important in order to be able to convey successfully the non-classical features of quantum mechanics. This paper discusses the epistemic and ontological implications of different new experiments that attempt to detect complementarity. Complementarity has surely survived the attempts to overcome it, yet some of these experiments have led to a more general form of complementarity. Others claim to be able to differentiate among the different interpretations of quantum physics. Nonetheless, such claims have revealed contradictory representations of the ontological picture of the universe. Hence, Bohr's position is still valid., Author(s): Towfic Shomar [sup.1] [sup.2] Author Affiliations: (1) grid.9670.8, 0000 0001 2174 4509, Department of Philosophy, Faculty of Arts, University of Jordan, , Amman, Jordan (2) grid.13063.37, 0000 0001 0789 [...]

This paper presents an account of how to evaluate formal models of science: models and simulations in social epistemology designed to draw normative conclusions about the social structure of scientific research. I argue that such models should be evaluated according to their representational and predictive accuracy. Using these criteria and comparisons with familiar models from science, I argue that most formal models of science are incapable of supporting normative conclusions., Author(s): Michael Thicke [sup.1] Author Affiliations: (1) grid.252838.6, 0000 0001 2375 3628, Bard Prison Initiative, Bard College, , PO Box 193, 12583, Tivoli, NY, USA Introduction [Displayed Quote]How do we [...]

We argue that inductive analysis (based on formal learning theory and the use of suitable machine learning reconstructions) and operational (citation metrics-based) assessment of the scientific process can be justifiably and fruitfully brought together, whereby the citation metrics used in the operational analysis can effectively track the inductive dynamics and measure the research efficiency. We specify the conditions for the use of such inductive streamlining, demonstrate it in the cases of high energy physics experimentation and phylogenetic research, and propose a test of the method's applicability., Author(s): Slobodan Perovic [sup.1] , Vlasta Sikimic [sup.1] Author Affiliations: (1) grid.7149.b, 0000 0001 2166 9385, Department of Philosophy, University of Belgrade, , Cika Ljubina 18-20, FIlozofski fakultet, 11000, Belgrade, [...]

Formal models of scientific inquiry, aimed at capturing socio-epistemic aspects underlying the process of scientific research, have become an important method in formal social epistemology and philosophy of science. In this introduction to the special issue we provide a historical overview of the development of formal models of this kind and analyze their methodological contributions to discussions in philosophy of science. In particular, we show that their significance consists in different forms of 'methodological iteration' (Elliott 2012 (See CR19)) whereby the models initiate new lines of inquiry, isolate and clarify problems with existing knowledge claims, and stimulate further research., Author(s): Dunja Seselja [sup.1] , Christian Straßer [sup.2] , AnneMarie Borg [sup.3] Author Affiliations: (1) grid.6852.9, 0000 0004 0398 8763, Philosophy and Ethics Group, TU Eindhoven, , Eindhoven, The Netherlands [...]

Using the example of architecture, this article defends the thesis that designing should not be regarded as a kind of experimenting. This is in contrast to a widespread methodological claim that design processes are equivalent to experimentation processes. The contrary thesis can be proven by focusing on actual practices, techniques and design strategies. Closely connected with the thesis is an even more important epistemological claim, which contends that designing serves not only to develop artefacts but is also a means of acquiring genuine knowledge. When the epistemic relevance of said practices, techniques and strategies is reassessed, designing emerges clearly as an independent epistemic praxis. To defend the thesis, the present article draws on and analyses empirical material from an ethnographic field study in order to back up the conceptual analysis., Author(s): Sabine Ammon [sup.1] [sup.2] Author Affiliations: (1) Institut für Berufliche Bildung und Arbeitslehre, Technische Universität Berlin, 0000 0001 2292 8254, grid.6734.6, , Marchstraße 23, 10587, Berlin, Germany (2) Institut [...]

Mechanistic accounts of explanation have recently found popularity within philosophy of science. Presently, we introduce the idea of an extended mechanistic explanation, which makes explicit room for the role of environment in explanation. After delineating Craver and Bechtel's (2007 (See CR18)) account, we argue this suggestion is not sufficiently robust when we take seriously the mechanistic environment and modeling practices involved in studying contemporary complex biological systems. Our goal is to extend the already profitable mechanistic picture by pointing out the importance of the mechanistic environment. It is our belief that extended mechanistic explanations, or mechanisms that take into consideration the temporal sequencing of the interplay between the mechanism and the environment, allow for mechanistic explanations regarding a broader group of scientific phenomena., Author(s): Sarah M. Roe [sup.1] , Bert Baumgaertner [sup.2] Author Affiliations: (1) Department of Philosophy, Southern Connecticut State University, 0000 0001 2111 4814, grid.263848.3, , 501 Crescent Street, 06515, New [...]

Many bacteria live in close association with sponges. Within these consortia, molecules of communication such as quorum-sensing and hormone-like molecules may occur in order to regulate the partnership. Of particular interest, bacterial N-acyl-L-homoserine lactones (AHLs) were screened in supernatants from Suberites domuncula-associated bacteria using an E. coli bioluminescent reporter system. These sponge-associated bacteria were beforehand isolated on several media supplemented or not with a sponge extract to attempt to isolate sponge-specific bacteria. Out of 81 AHL-producing bacteria, three strains requiring sponge extract to grow were selected for AHL characterization. The in vitro produced AHLs, that is, in bacterial culture supernatants, were identified as N-(3-butanoyl)-L-homoserine lactone and N-(3-oxododecanoyl)-L-homoserine lactone and quantified using LC-ESI-MS/MS. The in vivo production of AHLs by sponge-associated bacteria has also been demonstrated in a healthy host for the first time: N-(3-oxododecanoyl)-L-homoserine lactone, N-(3-hexanoyl)-L-homoserine lactone, and N-(3-heptanoyl)-L-homoserine lactone. This AHL production in sponges may suggest a potential role of these molecules between sponge-associated bacteria and/or between sponge-associated bacteria and the sponge., Introduction Since 700 million years, sponges and bacteria have co-evolved to form a symbiotic community sensu de Bary (1879). Despite an efficient innate immune system (Thakur et al. 2005; Wiens [...]

ABSTRACT The effects of the toxic dinoflagellate Heterocapsa circularisquama on the activity rate, development rate, prevalence of damage, and survival rate of trochophore and D-shaped larvae of the pearl oyster [...]

Introduction Children presenting with urolithiasis pose a challenge to the treating doctor, as they are part of the high-risk group for stone recurrence [1]. Although a rare disease in children [...], Children represent about 1% of all patients with urolithiasis, but 100% of these children are considered high risk for recurrent stone formation, and it is crucial for them to receive a therapy that will render them stone free. In addition, a metabolic workup is necessary to ensure a tailored metaphylaxis to prevent or delay recurrence. The appropriate therapy depends on localization, size, and composition of the calculus, as well as on the anatomy of the urinary tract. In specialized centers, the whole range of extracorporeal shock-wave lithotripsy (ESWL), ureterorenoscopy (URS), and percutaneous nephrolithotomy (PCNL) are available for children, with the same efficiency and safety as in adults. Keywords ESWL * PCNL * URS * Urolithiasis * Children * Pediatric urolithiasis * Endoscopy

Abstract The effect of hydrocortisone (HC), the steroid of lowest potency, and physiotherapy (PT) on non-retractile physiologic phimosis (PP) and the reduction of subsequent recurrent UTI was evaluated in male [...]

Abstract: Sponges secrete a variety of mineral skeletons consisting of calcite, aragonite, and (or) amorphous silica that confer strength and protect them from physical perturbations. Calcification takes place in a [...]

Abstract: Having descended from the first multicellular animals on earth, sponges are a key group in which to seek innovations that form the basis of the metazoan body plan, but [...]

Abstract: All multicellular organisms need a means of communicating between cells and between regions of the body. The evolution of a nervous system, by the Cnidaria, provided a fast means [...]

Abstract: Apoptosis represents the morphological manifestation of programmed cell death and, paradoxically at first sight, it is a prerequisite for metazoan life. Thus, apoptosis is responsible for the demise of [...]

Sponges (Porifera) represent the evolutionary oldest metazoan phylum still extant today. They havedeveloped a complex Bauplan, based on the existence of structural and regulatory molecules; many of these have been cloned and analyzed in the past years. The demosponge Suberites domuncula has been used as a suitable model to demonstrate that these animals not only possess an adaptive immune response on the level of cytokines, but also, as pointed out here, on the level of synthesis of bioactive alkyl-lipid derivatives. From specimens of S. domuncula the two lyso-PAF (platelet-activating factor) compounds, 1-O-hexadecyl-sn-glycero-3-phosphocholine and 1-O-octadecyl-sn-glycero-3-phosphocholine, have been identified and characterized. These two lyso-PAFs showed pronounced anti-bacterial activity. In the central part of this paper it is shown that the level of synthesis of the lyso-PAF congeners increased in response to the model compound, the endotoxin lipopolysaccharide (LPS). Treatment of the tissue with LPS for 72 h substantially increased the synthesis. In order to prove that the lyso-PAFs are really synthesized by the sponge, the key enzyme of the alkyl-dihydroxyacetonephosphate pathway, i.e. alkyl-dihydroxyacetonephosphate synthase (ADS), was cloned from S. domuncula. This sponge enzyme comprises the characteristic features of metazoan ADS enzymes; it is increasingly expressed in the tissue and in the in vitro cell culture system after exposure to LPS. These data are taken as a strong indication that bioactive, low-molecular weight, nonproteinaceous lipid derivatives function in an adaptive manner in response to the endotoxin., Introduction Sponges (Porifera) have been very successful during their long evolutionary history since they emerged approximately 600-800 million years ago (see Muller 2001). This is even more surprising since, even [...]

Summary Hypericum perforatum is an herbaceous perennial plant, also known as 'St. John's wort', used popularly as a natural antidepressant. Although some clinical and experimental studies suggest it has some [...]

Summary Effects of different extracts of HYPERICUM PERFORATUM L. on the kindling epileptic discharges were analyzed. The experiment was carried out on Chinchilla rabbits with chronically implanted electrodes in cortical [...]

Key Words review, interleukin-1, tumor necrosis factor, nerve growth factor, hyperalgesia, allodynia Abstract This review focuses on the powerful pain facilitatory effects produced by the immune system. Immune cells, activated [...]

Introduction The Porifera [sponges] are the oldest metazoan phylum; they existed 40 to 50 million years prior to the onset of the 'Cambrian Explosion' (Valentine et al., 1996), the time [...]