Critical behaviour of the Ising ferromagnet confined in quasi-cylindrical pores: A Monte Carlo study

The critical behaviour of the Ising ferromagnet confined in pores of radius R and length L is studied by means of Monte Carlo computer simulations. Quasi-cylindrical pores are obtained by replicating n-times a triangular lattice disc of radius R, where L = na and a is the spacing between consecutive replications. So, spins placed at the surface of the pores have less nearest-neighbours (NN) as compared to 8 NN for spins in the bulk. These “missing neighbour” effects undergone by surface spins cause a strong suppression of surface ordering, leading to an ordinary surface transition. Also, the effect propagates into the bulk for small tubes (R ≤ 12) and the effective critical temperature of the pores is shifted towards lower values than in the bulk case. By applying the standard finite-size scaling theory, subsequently supported by numerical data, we concluded that data collapse of relevant observables, e.g., magnetization (m), susceptibility, specific heat, etc., can only be observed by comparing simulation results obtained by keeping the aspect ratio C ≡ R/L constant. Also, by extrapolating “effective” R-dependent critical temperatures to the thermodynamic limit (R → ∞, C fixed), we obtained TC(∞) = 6.208(4). As suggested by finite-size scaling arguments, the magnetization is measured at the critical point scales according to |m| TcR β ν ∝ R L 1 2 , where β and ν are the standard exponents for the order parameter and the correlation length, respectively. Furthermore, it is shown that close to criticality the axial correlation length decreases exponentially with the distance. That result is the signature of the formation of (randomly distributed) alternating domains of different magnetization, which can be directly observed by means of snapshot configurations, whose typical length (ξ ) is given by the characteristic length of the exponential decay of correlations. Moreover, we show that at criticality ξ = 0.43(2)R.Instituto de Física de Líquidos y Sistemas BiológicosConsejo Nacional de Investigaciones Científicas y TécnicasComisión de Investigaciones Científicas de la provincia de Buenos Aire

Two glycerol uptake systems contribute to the high osmotolerance of Zygosaccharomyces rouxii

The accumulation of glycerol is essential for yeast viability upon hyperosmotic stress. Here we show that the osmotolerant yeast Zygosaccharomyces rouxii has two genes, ZrSTL1 and ZrSTL2, encoding transporters mediating the active uptake of glycerol in symport with protons, contributing to cell osmotolerance and intracellular pH homeostasis. The growth of mutants lacking one or both transporters is affected depending on the growth medium, carbon source, strain auxotrophies, osmotic conditions and the presence of external glycerol. These transporters are localised in the plasma membrane, they transport glycerol with similar kinetic parameters and besides their expected involvement in the cell survival of hyperosmotic stress, they surprisingly both contribute to an efficient survival of hypoosmotic shock and to the maintenance of intracellular pH homeostasis under non-stressed conditions. Unlike STL1 in Sa. cerevisiae, the two Z. rouxii STL genes are not repressed by glucose, but their expression and activity are downregulated by fructose and upregulated by non-fermentable carbon sources, with ZrSTL1 being more influenced than ZrSTL2. In summary, both transporters are highly important, though Z. rouxii CBS 732(T) cells do not use external glycerol as a source of carbon.The help of Dr. P. Ergang with the real-time PCR experiments is gratefully acknowledged. We thank O. Zimmermannova for critical reading of the paper. This work was supported by the following grants: Grant Agency of the Czech Republic P503/ 10/0307, institutional concept RVO:6798582, Grant Agency of the Charles University 299611/2011/B-Bio/PrF, an Lifelong Learning Programme ERASMUS practical placement grant and by Fundo Europeu de Desenvolvimento Regional – Programa Operacional de Fatores de Competitividade – COMPETE and by national funds from Fundação para a Ciência e Tecnologia through the project PEstC/BIA/UI4050/ 2011.info:eu-repo/semantics/publishedVersio

PROPOSAL FOR AN INTEGRATED SYSTEM FOR NATURAL DISASTERS RISK MANAGEMENT IN THE BRAZILIAN SCENARIO

This work presents a design for an Integrated Management System of Natural Disasters Risks (SIGRID), based on literature review about integral management of disasters risks and also on the authors’ experience related to operational and inter-institutional situations in the Brazilian protection and defense civil scenario. The combined analysis of the main current Brazilian systems was the starting point for the creation of this proposal. Those systems (System for Monitoring and Warnings of Natural Disasters/MCTI, System for Urban Occupation Monitoring/MCid and System for Information about Disasters/MI) provide complementary information and are responsible for joining information and other related systems in different scales (including municipalities, state and the whole country in some cases). The needs and the conceptual  inter-operational arrangement among systems were analyzed and the new system’s main characteristics and functions were defined. The proposed system’s mission highlights the connection of activities related to the Integral Management of Disasters Risks in Brazil, considering peculiarities of the country’s federative pact. The proposal is in accordance with the Brazilian Law 12.608/12.Partindo-se de uma pesquisa bibliográfica nos múltiplos assuntos relacionados à gestão integral de riscos de desastres e da observação participante dos autores por meio de vivência em situações operacionais e interinstitucionais no cenário de proteção e defesa civil brasileiro, propôs-se a criação de um Sistema Informatizado para Gestão Integral de Riscos de Desastres Naturais (SIGRID). A proposta foi construída a partir de uma análise conjugada dos principais sistemas nacionais em voga (Sistema de Monitoramento e Alertas de Desastres Naturais/MCTI, Sistema de Monitoramento da Ocupação Urbana/MCid e Sistema de Informações Sobre Desastres/MI) que, além de serem complementares, também teriam a função de congregar informações e sistemas já existentes nos âmbitos federal, estadual e municipal, que se mostrem afins com suas respectivas missões. Neste contexto, foram analisadas as necessidades e o arranjo interoperacional conceitual entre os sistemas existentes, bem como foram definidas as principais características e funcionalidades de um sistema informatizado cuja missão seja conectar as atividades relacionadas à Gestão Integral de Riscos de Desastres no Brasil, levando em conta as peculiaridades do pacto federativo do país. A proposta deste sistema está alinhada com a Lei 12.608/12

The VISCACHA survey-deep and resolved photometry of star clusters in the Magellanic Clouds

The VISCACHA (VIsible Soar photometry of star Clusters in tApii and Coxi HuguA†) Survey is an ongoing project based on deep and spatially resolved photometric observations of Magellanic Cloud star clusters, collected using the SOuthern Astrophysical Research (SOAR) telescope together with the SOAR Adaptive Module Imager. So far we have used >300h of telescope time to observe ∼150 star clusters, mostly with low mass (M < 104M⊠) on the outskirts of the LMC and SMC. With this high-quality data set, we homogeneously determine physical properties using deep colour-magnitude diagrams (ages, metallicities, reddening, distances, mass, luminosity and mass functions) and structural parameters (radial density profiles, sizes) for these clusters which are used as a proxy to investigate the interplay between the Magellanic Clouds and their evolution. We present the VISCACHA survey and its initial results, based on our first two papers. The project's long term goals and expected legacy to the community are also addressed.Fil: Dias, Bruno. European Southern Observatory Chile; Chile. Universidad Andrés Bello; ChileFil: Maia, Francisco. Universidade Federal do Rio de Janeiro; BrasilFil: Kerber, Leandro. Universidade Estadual de Santa Cruz; BrasilFil: Dos Santos, João F. C.. Universidade Federal de Minas Gerais; BrasilFil: Bica, Eduardo. Universidade Federal do Rio Grande do Sul; BrasilFil: Armond, Tina. Universidade Federal de São João del Rei; BrasilFil: Barbuy, Beatriz. Universidade de Sao Paulo; BrasilFil: Fraga, Luciano. Laboratório Nacional de Astrofísica; BrasilFil: Hernandez Jimenez, Jose A.. Universidad Andrés Bello; ChileFil: Katime Santrich, Orlando J.. Universidade Estadual de Santa Cruz; BrasilFil: Oliveira, Raphael A. P.. Universidade de Sao Paulo; BrasilFil: Pérez Villegas, Angeles. Universidade de Sao Paulo; BrasilFil: Piatti, Andres Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Quint, Bruno. Observatorio Gemini; ChileFil: Sanmartin, David. Observatorio Gemini; ChileFil: Angelo, Mateus S.. Centro Federal de Educação Tecnológica de Minas Gerais; BrasilFil: Souza, Stefano O.. Universidade de Sao Paulo; BrasilFil: Vieira, Rodrigo G.. Universidade de Sao Paulo; BrasilFil: Westera, Pieter. Universidad Federal Do Abc; BrasilFil: Parisi, Maria Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Geisler, Doug. Universidad de La Serena; Chile. Universidad de Concepción; ChileFil: Minniti, Dante. Universidad Andrés Bello; Chile. Millennium Institute of Astrophysics; Chile. Vatican Observatory; ItaliaFil: Saito, Roberto. Universidade Federal de Santa Catarina; BrasilFil: Bassino, Lilia Patricia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: de Bórtoli, Bruno Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: Figueiredo, André. Universidade de Sao Paulo; BrasilFil: Rímulo, Leandro. Universidad de los Andes; Colombi

Observation of out-of-plane vibrations in few-layer graphene

We report the observation of layer breathing mode (LBM) vibrations in few-layer graphene (FLG) samples of thickness from 2 to 6 layers, exhibiting both Bernal (AB) and rhombohedral (ABC) stacking order. The LBM vibrations are identified using a Raman combination band lying around 1720 cm-1. From double resonance theory, we identify the feature as the LOZO' combination mode of the out-of-plane LBM (ZO') and the in-plane longitudinal optical mode (LO). The LOZO' Raman band is found to exhibit multiple peaks, with a unique line shape for each layer thickness and stacking order. These complex line shapes of the LOZO'-mode arise both from the material-dependent selection of different phonons in the double-resonance Raman process and from the detailed structure of the different branches of LBM in FLG.Comment: 17 pages, 7 figures, supplemental material include

Ti-25Nb-25Ta alloy treated by plasma electrolytic oxidation in phosphoric acid for implant applications

Among titanium alloys with non-toxic elements, the Ti-25Nb-25Ta alloy has good elastic behavior for applications in osseous implants, biocompatibility, and excellent corrosion resistance. The present study aimed to better the biocompatibility characteristics of Ti-25Nb-25Ta alloy modifying its surface through Plasma Electrolytic Oxidation (PEO) treatment. The formed oxide coating is amorphous and composed of two distinct porous formations: smaller hole-shaped pores and larger volcano-like pores. The regions with the formation of smaller pores and in the hole shaped presented the highest atomic percentage of the chemical element phosphorus. Nanoindentation tests have shown that the hardness of the Ti-25Nb-25Ta alloy is slightly lower than the commercially pure grade 2 titanium (a material used as reference), while elastic modulus measurements of Ti-25Nb-25Ta presented more suitable values for implant application (lower values when compared with titanium reference). After PEO treatment there were significant mechanical surface improvements (increased fairly surface hardness and decreased elastic modulus) for application in osseous tissue. Despite the Ti-25Nb-25Ta alloy presented excellent characteristics for applications in hard biological tissues, the PEO treatment better its features.Keywords: Titanium alloy, Ti-25Nb-25Ta, nanoindentation, mechanical properties, Plasma Electrolytic Oxidation.

ATLANTIC EPIPHYTES: a data set of vascular and non-vascular epiphyte plants and lichens from the Atlantic Forest

Epiphytes are hyper-diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non-vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer-reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non-vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non-vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events. © 2019 The Authors. Ecology © 2019 The Ecological Society of Americ

Antitrust and Internet new business. Anticompetitive conducts or regular exercise of economic power?

As profundas mudanças trazidas pela sociedade da informação, em especial o advento da Internet, tiveram enorme impacto sobre as interações humanas, modificando a forma como as pessoas se relacionam e consomem bens e serviços. Nesse contexto, surgem inúmeros serviços prestados por empresas baseadas na rede mundial de computadores. Características destes novos mercados como o uso de plataformas de múltiplos lados, o uso intensivo de novas tecnologias, a presença de efeitos ou externalidades de rede, a interligação entre serviços distintos, o oferecimento de serviços de forma gratuita ao consumidor e o entrelaçamento entre os diversos serviços prestados, desafiam conceitos tradicionais do direito concorrencial como mercado relevante, poder de mercado e venda casada. Faz-se necessária, assim, a adaptação da metodologia de análise antitruste, por meio da analise dos fundamentos teóricos que dão suporte à sua aplicação, considerando-se as particularidades presentes nesses mercados. O presente estudo tem por objetivo analisar o controle de condutas nesses novos setores de Internet por meio da análise das particularidades econômicas desses novos setores e as consequências desse enfoque sobre a análise antitruste.The deep changes brought by the information society, especially the rising of the Internet, caused an enormous impact over human interactions, changing the way people relate and the way people consume goods and services. As a consequence of this new reality, services provided by web based companies emerged. Some characteristics of those new markets, such as the use of multiple side platforms, the intensive use of new technologies, the existence of network effects or network externalities, the connection of distinct services, the offer of zero price services and the deep connection between the services, challenge traditional concepts of antitrust law, like relevant market, market power and tying. Therefore, traditional antitrust analysis and its theoretical foundations must be reviewed, considering the particularities of those markets. The main objective of this study is to analyze the conduct control on these new Internet sectors, considering its economic particularities and the consequences of these view on antitrust analysis

Quandle Coloring and Cocycle Invariants of Composite Knots and Abelian Extensions

Quandle colorings and cocycle invariants are studied for composite knots, and applied to chirality and abelian extensions. The square and granny knots, for example, can be distinguished by quandle colorings, so that a trefoil and its mirror can be distinguished by quandle coloring of composite knots. We investigate this and related phenomena. Quandle cocycle invariants are studied in relation to quandle coloring of the connected sum, and formulas are given for computing the cocycle invariant from the number of colorings of composite knots. Relations to corresponding abelian extensions of quandles are studied, and extensions are examined for the table of small connected quandles, called Rig quandles. Computer calculations are presented, and summaries of outputs are discussed