Relationship between Degree of Deformation in Quartz and Silica Dissolution for the Development of Alkali-Silica Reaction in Concrete.

This paper presents research on the influence of quartz deformation in aggregates for the development of the alkali-silica reaction in concrete and its relationship with silica dissolution. The study also compares these characteristics with the field behavior of such rocks in concrete. The paper proposes parameters to classify the different degrees of deformation of quartz. Transmission electron microscopy showed the presence of walls even in slightly deformed quartz, which indicate the presence of the internal paths available to react with the alkaline concrete pore solutions and point to the potential development of an alkali-silica reaction. The presence of the deformation bands in the quartz grains leads to the alkali aggregate reaction occurring more rapidly. The visible spectrophotometer test was performed to evaluate the dissolution potential of the different samples of deformed quartz, which confirmed that the reactivity of the quartz increases as the deformation of the crystalline structure increases. The parameters established in the present study could be verified by analyzing the behavior of reactive and innocuous aggregates from the buildings

Complement reaction in leprosy. Activation by potassium Iodide

nuloI n 1929, while we studied the effects of the administration of potassium iodide to lepers for the purpose of obtaining a complement reaction (the fat free bacillus of Deycke being used as antigen) we had occasion to note that, almost all cases were activated, so that individuais with a previous negative serum reaction, in spite of the existence of some syrnptoms of leprosy, became positive cases

DNA markers to study genetic diversity and fingerprinting in Arbutus unedo L. (strawberry tree)

Strawberry tree (Ericaceae) is a species of Mediterranean climates growing in several countries of the Mediterranean basin as well as in Portugal and Ireland. The edible fruits have been used in different ways yet the production of a popular spirit is still the main application. The species is also interesting from an ecological perspective since it is drought tolerant and fire resistant. In spite of its large distribution in Portugal little is known about the genetic diversity of the species and no efforts have been carried out to select the most interesting trees. Material from selected trees (based on fruit production) in a total of 27 was collected all around the country covering the distribution area of the species. In order to find out DNA markers to characterise genetic diversity and to fingerprint Arbutus unedo, random amplified polymorphic DNA (RAPD) and microsatellite markers (SSR) were used. The set of 20 RAPD primers used generated 124 bands, from which 71 (57.3%) were polymorphic and the expected heterozygosity was 0.27±0.014. The cluster analysis (UPGMA) based on the Jaccard similarity index showed a similarity of 71% among the trees of different origins. Only four genotypes could be grouped according to their geographical distribution. Eleven SSR primers designed for Vaccinium (an Ericaceae as A. unedo) were selected according to their polymorphism, number of alleles per locus, cross-amplification, allele scoring quality and the repeat motif, and were tested in A. unedo. Six loci showed to be polymorphic, with 71% mean expected diversity, 10.5 mean number of alleles, and 67% of average polymorphic information content. A mean homozygote excess was found (11%) although not significant. Estimation of null allele frequency was about 9% on average. The linkage disequilibrium test showed that all the loci were independent. The UPGMA clustering based on the Lynch and Ritland coefficient showed that only two genotypes shared about 50% of the alleles, but without a consistent geographic pattern, similarly to the results obtained by RAPD analysis. The Mantel test confirmed that there is no correlation between the genetic and the geographical distance matrices, for both makers. Reduced gene flow, due to fragmentary distribution, together with the type of mating system of this species (pollination by small insects), are plausible explanations for these results. As far as we know our work is the first detailed study to evaluate A. unedo diversity by molecular markers opening new perspectives for fingerprinting analysis and for conservation and improvement purposes

Large Aperiodic Semigroups

The syntactic complexity of a regular language is the size of its syntactic semigroup. This semigroup is isomorphic to the transition semigroup of the minimal deterministic finite automaton accepting the language, that is, to the semigroup generated by transformations induced by non-empty words on the set of states of the automaton. In this paper we search for the largest syntactic semigroup of a star-free language having $n$ left quotients; equivalently, we look for the largest transition semigroup of an aperiodic finite automaton with $n$ states. We introduce two new aperiodic transition semigroups. The first is generated by transformations that change only one state; we call such transformations and resulting semigroups unitary. In particular, we study complete unitary semigroups which have a special structure, and we show that each maximal unitary semigroup is complete. For $n \ge 4$ there exists a complete unitary semigroup that is larger than any aperiodic semigroup known to date. We then present even larger aperiodic semigroups, generated by transformations that map a non-empty subset of states to a single state; we call such transformations and semigroups semiconstant. In particular, we examine semiconstant tree semigroups which have a structure based on full binary trees. The semiconstant tree semigroups are at present the best candidates for largest aperiodic semigroups. We also prove that $2^n-1$ is an upper bound on the state complexity of reversal of star-free languages, and resolve an open problem about a special case of state complexity of concatenation of star-free languages.Comment: 22 pages, 1 figure, 2 table

Microlenses array made with AZ4562 photoresist for stereoscopic acquisition

In this paper is presented a fabrication process for obtaining refractive microlenses arrays with high reproducibility and low cost. This process was specifically optimized for the AZ4562 photoresist. Functional prototypes of microlenses arrays with dimensions in the range of 30 m, 4.9 mm and 5 m for width, length and thickness, respectively, were fabricated and tested. The pre-thermal reflow spacing between adjacent isosceles trapezoids is 1.35-5.43 m, from bottom to top, respectively. This separation allows the photoresist to reflow and join the adjacent microlens creating a consistent and homogeneous array.This work and Rui Pedro Rocha are fully supported by the Portuguese Foundation for Science and Technology under the project FCT/PTDC/EEA-ELC/109936/2009 and the financial grant SFRH/BD/33733/2009, respectively. The authors would also like to acknowledge Dr.-Ing Christian Koch from MicroChemicals GmbH for the technical support

On the properties of the interstellar medium in extremely metal-poor blue compact dwarf galaxies : GMOS-IFU spectroscopy and SDSS photometry of the double-knot galaxy HS 2236+1344

Aims. The main goal of this study is to carry out a spatially resolved investigation of the warm interstellar medium (ISM) in the extremely metal-poor blue compact dwarf (BCD) galaxy HS 2236+1344. Special emphasis is laid on analysis of the spatial distribution of chemical abundances, emission-line ratios, and the kinematics of the ISM, and to the recent star-forming (SF) activity in this galaxy. Methods. This study is based on optical integral field unit spectroscopy data from Gemini Multi-Object Spectrograph (GMOS) at the Gemini North telescope and archival Sloan Digital Sky Survey (SDSS) images. The galaxy was observed at medium spectral resolution over the spectral range from ∼4300 Å to 7300 Å. The data were obtained in two different positions across the galaxy, obtaining a total 4″ × 8″ field that encompasses most of its ISM. Results. Emission-line maps and broad-band images obtained in this study indicate that HS 2236+1344 hosts three giant H'ii regions (GH'iiRs). Our data also reveal some faint curved features in the BCD periphery that might be due to tidal perturbations or expanding ionized-gas shells. The ISM velocity field shows systematic gradients along the major axis of the BCD, with its southeastern and northwestern half differing by ∼80 km's-1in their recessional velocity over the field of view. The Hα and Hβ equivalent-width distribution in the central part of HS 2236+1344 is consistent with a very young (∼3 Myr) burst. Our surface photometry analysis reveals an underlying low surface brightness component with moderately red colors, which suggest that the galaxy has undergone previous star formation. We derive an integrated oxygen abundance of 12 + log'(O / H) = 7.53 ± 0.06 and a nitrogen-to-oxygen ratio of log'(N / O) = -1.57 ± 0.19. Our results are consistent, within the uncertainties, with a homogeneous distribution of oxygen and nitrogen within the ISM of the galaxy. The high-ionization He'ii λ4686 emission line is detected only in the central part of HS 2236+1344. Similar to many BCDs with He'ii λ4686 emission, HS 2236+1344 shows no Wolf-Rayet (WR) bump.Instituto de Astrofísica de La PlataFacultad de Ciencias Astronómicas y Geofísica

Evaluation of the cardiovascular effects of vasicine, an alkaloid isolated from the leaves of Sida cordifolia L. (Malvaceae)

The cardiovascular effects of vasicine, an alkaloid isolated from the leaves of Sida cordifolia L., were evaluated in this work. In non-anaesthetized rats (n=6), vasicine (1, 2.5, 5 and 10 mg/kg; i.v., randomly) induced hypotension associated with an intense bradycardia. Both responses were completely abolished after atropine (2mg/Kg; i.v.) and attenuated after hexamethonium (20 mg/Kg; i.v.). In isolated rat mesenteric artery rings, vasicine (0.03, 0.1, 0.3, 1, 3, 10, 30, 100 and 300 μg/mL, cumulatively) induced concentration-dependent relaxation of phenylephrine-induced tone (IC50= 3.8±0.9 μg/mL; n = 6). In conclusion, the results show that vasicine produce hypotension and bradycardia which appears to be due to the stimulation of cardiac muscarinic receptors (directly and/or indirectly), and by a decrease of the peripheral resistances

Producing and Detecting Correlated atoms

We discuss experiments to produce and detect atom correlations in a degenerate or nearly degenerate gas of neutral atoms. First we treat the atomic analog of the celebrated Hanbury Brown Twiss experiment, in which atom correlations result simply from interference effects without any atom interactions.We have performed this experiment for both bosons and fermions. Next we show how atom interactions produce correlated atoms using the atomic analog of spontaneous four-wavemixing. Finally, we briefly mention experiments on a one dimensional gas on an atom chip in which correlation effects due to both interference and interactions have been observed.Comment: to appear in conference proceedings "Atomic Physics 20

Stationary solutions for the parity-even sector of the CPT-even and Lorentz-covariance-violating term of the standard model extension

In this work, we focus on some properties of the parity-even sector of the CPT-even electrodynamics of the standard model extension. We analyze how the six non-birefringent terms belonging to this sector modify the static and stationary classical solutions of the usual Maxwell theory. We observe that the parity-even terms do not couple the electric and magnetic sectors (at least in the stationary regime). The Green's method is used to obtain solutions for the field strengths E and B at first order in the Lorentz- covariance-violating parameters. Explicit solutions are attained for point-like and spatially extended sources, for which a dipolar expansion is achieved. Finally, it is presented an Earth-based experiment that can lead (in principle) to an upper bound on the anisotropic coefficients as stringent as $(\widetilde{\kappa}_{e-}) ^{ij}<2.9\times10^{-20}.$Comment: 8 pages, revtex style, revised published version, to appear in EPJC (2009

Produção de azeitona e estado nutritivo das árvores após quatro anos sem fertilização com azoto e boro

Azoto e boro podem ser lixiviados dos solos por acção da água das chuvas de inverno. Por conseguinte, a aplicação destes elementos é feita anualmente numa dose única ou, eventualmente, de forma fraccionada, no caso do azoto. Contudo, literatura controversa sugere que no olival não haverá necessidade de se aplicar azoto anualmente se os teores foliares estiverem na zona de concentrações adequadas. Neste trabalho, o efeito da aplicação de N e B na produção, na concentração dos elementos nas folhas e na disponibilidade de N e B no solo foram investigados num ensaio de campo localizado em Trás-os-Montes, no qual estes dois elementos não foram aplicados durante quatro estações de crescimento consecutivas. Os tratamentos consistiram em: testemunha, no qual foi aplicado um plano de fertilizante completo (N+B); -N, em que o N foi excluído do plano de fertilização e -B em que foi excluído o B