Top PDF A new look at some old animals.

A new look at some old animals.

A new look at some old animals.

Of the five groups, the position of the placozoans has perhaps been the most contentious. They are clearly animals by virtue of having four somatic (i.e., non-reproductive) cell types— cover, cylinder, gland, and fiber cells [1,2]. All other animals, however, have many more somatic cell types. Further, the cell-level dynamics of Trichoplax are unusual. While cylinder cells may give rise to gland cells, otherwise the three major cell types (cover, cylinder, and fiber) give rise to their own cell type and none other during growth and reproduction. In contrast to other early diverging animals, placozoans do not seem to have a stem cell lineage that gives rise to more than one cell type (but see [2] for further discussion). Although the process is incompletely studied, placozoans do form germ cells, apparently from the somatic cells of the lower epithelium [1]. Cells are organized into two surface layers—a functional lower and upper side. Both cell layers lack underlying “basal lamina”—an extracellular matrix on which the cells sit—or other traces of such a matrix. These microscopic structures are found in all other animals [1–3]. Both sides of a placozoan are covered with flagella, with a higher density on the lower side. Morphologically, a living Trichoplax resembles a small, often highly irregular “plate” of cells, 2–3 mm in diameter, moving by means of flagella and constantly changing in outline (Video S1). Individuals are free-living and heterotrophic, but their natural history remains poorly known [4].
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Electrical Conductivity of Metals: A New Look at this Subject

Electrical Conductivity of Metals: A New Look at this Subject

while it is convenient to consider that an equivalent way to treat the problem is by taking in account the electromagnetic interaction through the dependence of the energy levels of the system on the fine structure constant α. We reproduce here some steps of the reasons outlined in reference [3]. One of the simplest models which exhibits energy levels dependence on the fine structure α is the Bohr atom, namely

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New models of old(?) payment questions

New models of old(?) payment questions

Why do we assert that the 19th century debates were never satisfacto- rily resolved? At the beginning of the 20th century, the dominant monetary theory consisted of the classical dichotomy. While that theory could accom- modate private credit instruments that to some extent substitute for outside or base money, either by treating such substitutes as part of the stock of a broader concept of money or by treating them as increasing the veloc- ity of outside or base money, neither treatment could say anything about the welfare consequences of di¤erent monetary systems—or, for that matter, the welfare consequences of money. At the beginning of the 21st century, the dominant monetary theory consists of descendents of the classical dichotomy: models with real balances in utility or production functions or models with cash-in-advance constraints. These descendents were designed to overcome the blatant inconsistencies of the classical dichotomy—the kind of inconsis- tency that Patinkin [13] pointed out. They were not designed to and cannot address the questions raised in the 19th century debates any better than could the classical dichotomy.
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Fast and furious: a look at the death of animals on the highway MS-080, Southwestern Brazil

Fast and furious: a look at the death of animals on the highway MS-080, Southwestern Brazil

Further, the recorded number of vertebrates in this study may be an underestimate, since some animals that are hit by vehicles fall off to the side of the road or are able to get off the highway but later die undetected. In addition, carcasses can be consumed by birds of prey and scavengers such as the southern crested caracara (Caracara plancus) or the black vulture (Coragyps atratus).

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A look at S&T Awareness - Enhancements in India

A look at S&T Awareness - Enhancements in India

No doubt that there are hurdles caused by market forces. But the sustained efforts have usually borne fruit as far getting people interested in science is concerned. The difference in the response of people caused by the positive media impact were clearly visible in the overwhelming response to the Total Solar Eclipse (TSE)- 1995. This was in stark contrast with the deserted roads in 1980 during another TSE. It certainly added to the appeal of the telecast that show was joined in by some well known scientists who were also renowned science communicators. Author's own experience while in Iradatganj (Allahabad), UP for live commentary for national television channel on the Total Solar Eclipse was an eye-opener. People, young and old, flocked from rural areas to the place where the crew camped. Not only this, on the previous night, over 600 children had gathered (missing on their fun of Deewali festival) to talk to scientists and listen to the lectures. During the eclipse, they observed it using filters and projecting through telescopes. They were still there to hear the speakers again after the telecast was over in the morning. So it may not be proper to question the scientific curiosity among the rural people. Another show when media played a great role was the Venus- Transit across the Sun in 2004. It was there on all channels of audio, AV and print media and attracted a very large number of people in many cities all over India, wherever telescopes were arranged to view the event and media covered it very well.
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Novo cenário, novas configurações: um olhar sobre a publicidade na era da informação New scenery, new formats: a look at advertising in the information age

Novo cenário, novas configurações: um olhar sobre a publicidade na era da informação New scenery, new formats: a look at advertising in the information age

The technological advances of the last decade make up a new world, where the digital permeates society in its various forms. In this new scenario, people and their everyday life change, mediated by new technologies, new tools. This transformation reflects in the contemporary communication and, consequently, in the traditional advertising. There is a new consumer, participative, that with the new technologies in his hands avoids the old advertising break and requires a more interesting speech. The advertising begins, then, to revise its core and innovate in their format and content. The entertainment seems to be the current strategy, revealing "maps" to reach that consumer. But there is still much to learn. Here, we launch a glance at the thought of some contemporary authors, focusing on changes that the information age generate on individuals, human relationships and, consequently, on the communication media. It appears urgent immerse in the bowels of advertising, to discover the paths that will lead to its "rebirth."
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A new look at online attraction: unilateral initial attraction and the pivotal role of perceived similarity

A new look at online attraction: unilateral initial attraction and the pivotal role of perceived similarity

on actual similarities, or on wide range of objective criteria (Finkel et al., 2012). However, our findings clearly showed that perceived similarity (i.e., a mental construct) is associated with UIA and helps promote interest in interacting with another person, and other researchers have shown that perceived similarity is associated with romantic relationship maintenance (Fletcher, Simpson, & Thomas, 2000). Hence, failing to account for this variable in online dating services may decrease matching efficiency and users’ satisfaction. Although our theoretical model does not directly translate into algorithms that online dating services could implement, some of our findings might be of relevance. These services can match users based on actual similarity, but make more salient the reason why users were matched (or display the number of shared attributes). For instance, one user can be matched to another, and receive automatically a private message listing which (or how many) aspects were similar between them. Making this information more salient could boost perceived similarity, which in turn could influence a first approach to the other user (e.g., start an interaction by making a comment about the type of food both users prefer), and pave the way for subsequent interactions.
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Connection coefficients and zeros of orthogonal polynomials

Connection coefficients and zeros of orthogonal polynomials

We discuss an old theorem of Obrechko and some of its applications. Some curious historical facts around this theorem are presented. We make an attempt to look at some known results on connection coecients, zeros and Wronskians of orthogonal polynomials from the perspective of Obrechko ’s theorem. Necessary conditions for the positivity of the connection coecients of two families of orthogonal polynomials are provided. Inequalities between the kth zero of an orthogonal polynomial p n (x) and the largest (smallest) zero of another orthogonal polynomial q n (x) are given in terms
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New environments of media exposure. Internet and narrative structures: From media education to media pedagogy and media literacy

New environments of media exposure. Internet and narrative structures: From media education to media pedagogy and media literacy

When we speak about new media, we generally speak about devices that have emerged in our daily life environment rather recently. They have, however, rather quickly accomplished a reshaping of some of our an- cient habits of personal communication and our most common communicative patterns of media usage. At first glance, these new patterns of communication and media usage seem many times to be so complex that we feel tempted to claim that we are entering, with them and via them, into a new paradigm of personal and social communication. It may well be so, and that is why we must ob- serve and study them. However, when we look more closely at these new patterns, we see that although they are developing devices and postures upon new complex and diffe- rentiated channels of communication, these new environments of media exposure may not have developed, apparently, any new nar- rative functions that would differentiate the new from older and more canonical environ- ments, like the folktales or the various nar- rative arts and genres. This probably im- plies that although we have definitely got some new complex environments of media exposure we may still study them and their processes, in accordance with some of the best known narrative structural dispositions and their analytical models. However, we really don’t know if this is so, and there- fore there is an urgent need for research and in-depth studies into the new environments of media exposure and their publics, that is, their dramatis personae. If, however the functions appear to be essentially the same, we already know that the structures of expo- sure and their patterns of reception are much
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Nature, Food, Crisis: New Problems, Old Debates

Nature, Food, Crisis: New Problems, Old Debates

In Part 2 (chapters 7 and 8), Tilzey discusses “crisis and resistance”. Tilzey’s previously defined ontology implies that crises are always “political” or legitimacy crises; an objective crisis of capitalism is out of question a priori (as well as the possible transition to a less democratic social order). In this respect, he distances himself from other authors for whom alienation plays a central role in crisis theory and that do consider the possibility of some kind of “regressive” transition, such as Moishe Postone or Robert Kurz, and is at least in this regard (crisis necessarily as crisis of legitimacy) in agreement with a non-Marxist scholar like Wolfgang Streeck. 15 In his exposition in chapter 7, Tilzey
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A Closer Look at Brazilwood and its Lake Pigments

A Closer Look at Brazilwood and its Lake Pigments

presence together with the polysaccharide binder alone, such as that presented in Figure 20B, are the most common (present in 5 of the 8 folios analysed) and good matches with those from reconstructions were found. Sometimes calcium carbonate (1408, 875 and 713 cm -1 ) is also present. Curiously, the latter was not found alone but always with gypsum. Possibly, chalk could have been converted into gypsum similarly to what was once observed with the medieval historically accurate reconstructions. Moreover, in manuscript 24, folio 60r two almost identical spectra revealing the present of the two white compounds were obtained for a pink and a dark red colour (Appendix 12, Figures A46.B and A47.A), the only difference being the proportion between gypsum and chalk. Even more interesting was the finding of a very small wood scrape over a black mantle from manuscript 24, folio 116v. Its infrared spectrum (Figure 21A) reveals the presence of the cellulose pattern (1160, 1115 and 1060 cm -1 ) and other bands at 1560, 1500, 1460, 1428, 1375, 1327, 1240 and 900 cm -1 that matches with the brazilwood spectrum (Appendix 7, Figure A21.A). Also, in a pink colour from manuscript 22, folio 76v, a similar spectrum was obtained and a good match with one medieval reconstruction painted with gum-arabic (chapter 8, experience 1, during which manufacture the filtration step was omitted) was obtained. Here, no binder could be clearly detected, although, in the case of the reconstructed pigment, a polysaccharide medium (gum-arabic) was used.
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Health implications of viruses from South American monkeys

Health implications of viruses from South American monkeys

The demonstration that herpesviruses of some of these New World monkeys can induce rapidly fatal malignant disease in animals is adding impetus to work on viruses [r]

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Old theses, new data: a methodological analysis.

Old theses, new data: a methodological analysis.

Para encerrar o tópico do cálculo da medida, assinale-se que o valor do índice F é sensível ao número de partidos e de lugares em disputa, o que quer dizer que parlamentos diferentes em [r]

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Fabrication of biocompatible hydrogels from pine resin

Fabrication of biocompatible hydrogels from pine resin

was changed every 8 hours for the first day, every day for the first week and weekly thereafter to keep the pH rela- tively constant. 15 Films were withdrawn at intervals of 30, 60, and 90 days, washed with distilled water, dried and subjected to analysis. The films have been subcuta- neously implanted on the backs of male Wistar [24] rats (200-300g) to monitor the in vivo degradation. Anaesthe- sia was induced by intraperitoneal injection of a mixture of ketamine HCl (85 mg/kg bodyweight) and xylazine (12 mg/kg body weight). Tetracycline, 10 mg/kg dose, was given at the time of surgery. An incision (2.5 cm) was inflicted laterally about the mid-portion of the back. Subcutaneous pockets were formed around each incision, free film was inserted, and the wounds have been sealed by intermittent nylon stitches at 0.5 cm apart. Films were explanted at 30, 60, and 90 days for analysis [25-26]. In these studies the authors have broadly justify the biocom- patibility of rosin as a material for exclusive use in living organism.
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Cosimo III e il mondo glabale di metà seicento attraverso la collezione delle carte di castello

Cosimo III e il mondo glabale di metà seicento attraverso la collezione delle carte di castello

and stylistic features, combined with a technique and taste for miniaturist painting, Johannes Vingboons copied images and cartographic materials that arrived in Amster- dam from all over the colonial world: the Antilles, the coasts of North, Central and South America (including New Spain and Portuguese Brazil), central Atlantic Africa and the Cape of Good Hope, India, Sri Lanka, ‘Ilha Formosa’ (present-day Taiwan), Malacca, the Maluku Islands and the Banda Islands, and other seaports in Indonesia, the Philippines and Japan. 10 These maps, extremely diverse in terms of their author-
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Aproveitando o valor do cliente através de experiências co-criativas: um olhar sobre as empresas hoteleiras

Aproveitando o valor do cliente através de experiências co-criativas: um olhar sobre as empresas hoteleiras

tourist becomes a direct contributor to their own experience at any stage, as well as an active parti- cipant in experiential activities on-site (Campos et al., 2018; Prebensen and Foss, 2011). In this res- pect, a new stream of research on creative tourism has been motivating a closer look at co-creation by examining creative tourism propositions based on experiences which require the active participa- tion of the tourist (Hung, Lee & Huang, 2014; Ri- chards, 2011; Ramos, Rosová & Campos, 2019). In fact, experiential value has been associated by prior research with own performance (Prebensen and Foss, 2011; Wikström, 2008), experiential authenticity (Mkono, 2012), and higher experience memorability (Campos et al., 2017). Own per- formance, in this co-creation approach, occurs at dierent levels, ranging from physical to intellec- tual, when tourists apply personal resources during participation e.g. in workshops, language cour- ses, creative sports or role-play touristic activities (Mathisen, 2013; Richards & Wilson, 2006).
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Eremogone (Caryophyllaceae): new combinations for Old World species

Eremogone (Caryophyllaceae): new combinations for Old World species

ten apiculate. Inlorescence of one or more terminal cymes, sometimes compressed to head-like, sometimes lowers solitary or paired. Flowers weakly perigynous. Sepals often hardened at base, veins 1–3, margins often white-scarious. Petals white, rarely pink. Floral glands (nectaries) at base of the antisepalous ilaments often lobed, conspicuous.

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Such were the times Serbian peasant women born in the 1920s and 1930s and the stories of their lives

Such were the times Serbian peasant women born in the 1920s and 1930s and the stories of their lives

the worst position in the hierarchy is that of a young woman. Some of the interviewees explain that they even feared their younger brothers. Gener- ally, they explain their position as part of the then existing rules, so they not only considered it acceptable, but normal. In fact, they saw it as the only possibility in such a value system and the prevailing social order. But, at the same time they are aware that the people they are talking to have completely different value systems, so that a difference between “their time” and “this time” is often stressed:

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Regional and large-scale patterns in Amazon forest structure and function are mediated by variations in soil physical and chemical properties

Regional and large-scale patterns in Amazon forest structure and function are mediated by variations in soil physical and chemical properties

would increase tree turnover rates, this correlation is taken here as an indication of regional patterns of rainfall distribution. Specifically, most areas included in this study do not suffer strong water deficits, as the great majority of sites never reach modelled AWC values below 20% (Fig. 5). However, the time (months) in which <20% AWC was attained had some potential to explain tree turnover rates in some specific areas. Soils

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The Librarian as an Agent of Change

The Librarian as an Agent of Change

Let not some future library historian look back at our moment in time and say they could have adapted , they would have met change , but they failed to act.[r]

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