263 research outputs found
Does it Take a Lula to go to Davos? A Brief Overview of Brazilian Reforms, 1980-2000
What are the determinants of economic reform efforts? This paper tries to throw light on this question by examining recent reforms in Brazil, a country which followed a gradualist approach and was a late-starter among Latin American economies. We argue that these first generation reforms (trade liberalization, stabilization, privatization and the adoption of a new macro-policy framework) were driven by the drastic growth slowdown and redemocratization of the 1980s. We argue that their gradual and democratic implementation not only respond for their sustainability but also shows that the country is ready for a second generation of reforms focusing explicitly on institutional deficiencies.Reform, Stabilization, Economic Policy, Growth, Brazil
Electron delocalization in planar metallacycles : HĂŒckel or Möbius aromatic?
In this work the relationship between the formal number of Ï-electrons, d-orbital conjugation topology, Ï-electron delocalization and aromaticity in d-block metallacycles is investigated in the context of recent findings concerning the correlation of Ï-HOMO topology and the magnetic aromaticity indices in these species. It is demonstrated that for Ï-electron rich d-metallacycles the direct link between aromaticity, the number of Ï-electrons and the frontier Ï-orbital topology does not strictly hold and for such systems it is very difficult to unambiguously associate their aromaticity with the '4n+2' (HĂŒckel) and '4n' (Möbius) rules. It is also shown that the recently proposed electron density of delocalized bonds (EDDB) method can successfully be used not only to quantify and visualize aromaticity in such difficult cases, but also - in contrast to magnetic aromaticity descriptors - to provide a great deal of information on the real role of d-orbitals in metallacycles without the ambiguity of bookkeeping of electrons in the Ï-subsystem of the molecular ring. Interestingly, some of the metallacycles studied cannot be classified exclusively as HĂŒckel or Möbius because they have a hybrid HĂŒckel-Möbius or even quasi-aromatic natur
Antibiotic resistance genes detected in the marine sponge <i>Petromica citrina</i> from Brazilian coast
Although antibiotic-resistant pathogens pose a significant threat to human health, the environmental reservoirs of the resistance determinants are still poorly understood. This study reports the detection of resistance genes (ermB, mecA, mupA, qnrA, qnrB and tetL) to antibiotics among certain culturable and unculturable bacteria associated with the marine sponge Petromica citrina. The antimicrobial activities elicited by P. citrina and its associated bacteria are also described. The results indicate that the marine environment could play an important role in the development of antibiotic resistance and the dissemination of resistance genes among bacteria
Does it Take a Lula to go to Davos? A Brief Overview of Brazilian Reforms, 1980-2000
What are the determinants of economic reform efforts? This paper tries to throw light on this question by examining recent reforms in Brazil, a country which followed a gradualist approach and was a late-starter among Latin American economies. We argue that these first generation reforms (trade liberalization, stabilization, privatization and the adoption of a new macro-policy framework) were driven by the drastic growth slowdown and redemocratization of the 1980s. We argue that their gradual and democratic implementation not only respond for their sustainability but also shows that the country is ready for a second generation of reforms focusing explicitly on institutional deficiencies.http://deepblue.lib.umich.edu/bitstream/2027.42/39966/3/wp580.pd
Characterization of Staphylococcus spp. strains in milk from buffaloes with mastitis in Brazil: the need to identify to species level to avoid misidentification.
ABSTRACT - Mastitis is an inflammation of the mammary gland that affects dairy cattle worldwide causing economic losses. Coagulase-negative staphylococci (CNS) are the predominant cause of this type of infection. We have recently showed that coagulase-positive staphylococci could be misidentified. So, the aim of this study was to characterize the Staphylococcus spp. strains initially classified as coagulase-negative Staphylococci, isolated from buffalo with subclinical mastitis. Milk of buffaloes with mastitis in herds was collected and 9 strains were identified as CNS by phenotypic tests. Molecular methodologies latter identified the strains as coagulase-negative Staphylococcus chromogenes (5), coagulase-positive Staphylococcus hyicus (2) and coagulase-positive Staphylococcus aureus (2). Our results strongly support the need to identify the isolates to a species level in order to avoid misidentification and to be aware of the classification using the coagulase test alone. RESUMO - A mastite Ă© uma inflamação da glĂąndula mamĂĄria que afeta o gado leiteiro em todo o mundo, causando perdas econĂŽmicas. Staphylococcus coagulase-negativa (SCN) sĂŁo a causa predominante desse tipo de infecção. Mostrou-se recentemente que Staphylococcus coagulase-positiva podem ser identificados erroneamente. Assim, o objetivo deste estudo foi caracterizar cepas de Staphylococcus spp. inicialmente classificados como Staphylococcus coagulase-negativa, isolados de bĂșfalas com mastite subclĂnica. O leite de bĂșfalas com mastite foi coletado, e nove cepas foram identificadas como SCN por testes fenotĂpicos. Metodologias moleculares identificaram as cepas como Staphylococcus chromogenes coagulase-negativa (5) Staphylococcus hyicus coagulase-positiva (2) e Staphylococcus aureus coagulase-positiva (2). Os resultados reforçam a necessidade de identificar as cepas em termos de espĂ©cie, a fim de se evitarem erros de identificação e estar atento Ă classificação utilizando o teste de coagulase sozinho
Orogenias paleozoicas en los Andes de Argentina y Chile y en la PenĂnsula AntĂĄrtica
Congreso GeolĂłgico Argentino (20Âș. 2017. San Miguel de TucumĂĄn, Argentina). Simposio de TĂ©ctonica pre-andinaDurante el Neoproterozoico y Paleozoico, los Andes de Argentina y Chile, y desde fines del Paleozoico tambiĂ©n la PenĂnsula AntĂĄrtica, formaron parte del margen SO de Gondwana. Durante este tiempo se acrecionaron a dicho margen varios fragmentos continentales de tamaño y aloctonĂa variable; denominados de N a S: Antofalla, Chi-Cu, Patagonia Occidental y AntĂĄrtida Occidental. Estos fragmentos formaban parte de placas litosfĂ©ricas, en ocasiones divididas en subplacas. La colisiĂłn de dichos fragmentos continentales con Gondwana y una Ășltima subducciĂłn bajo dicho margen, dieron lugar a 6 orogenias de extensiĂłn temporal y espacial limitada.Instituto GeolĂłgico y Minero de España, EspañaDepartamento de GeologĂa, Universidad de Oviedo, EspañaUniversidad de RĂo Negro, ArgentinaServicio GeolĂłgico y Minero Argentino, ArgentinaInstituto De Bio y Geociencias Del NOA, Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas, ArgentinaInstituto De Bio y Geociencias Del NOA, Universidad Nacional de Salta, ArgentinaDepartamento de GeodinĂĄmica, Universidad del PaĂs Vasco, EspañaFacultad de GeologĂa, Universidad de Barcelona, EspañaDepartamento de GeologĂa, Universidad de Chile, ChileUniversidad AndrĂ©s Bello, ChileUnidad de TectĂłnica, Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas, ArgentinaFacultad de GeologĂa, Universidad de Buenos Aires, ArgentinaĂrea de GeologĂa, Universidad Rey Juan Carlos, EspañaUniversidad de Salta, ArgentinaInstituto de InvestigaciĂłn en PaleobiologĂa y GeologĂa, Universidad de RĂo Negro, ArgentinaInstituto de InvestigaciĂłn en PaleobiologĂa y GeologĂa, Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas, ArgentinaCentro de Investigaciones GeolĂłgicas, Universidad de La Plata, ArgentinaUniversidad de San Juan, ArgentinaPeer reviewe
Remarks on Dirac-like Monopole, Maxwell and Maxwell-Chern-Simons Electrodynamics in D=(2+1)
Classical Maxwell and Maxwell-Chern-Simons (MCS) Electrodynamics in (2+1)D
are studied in some details. General expressions for the potential and fields
are obtained for both models, and some particular cases are explicitly solved.
Conceptual and technical difficulties arise, however, for accelerated charges.
The propagation of electromagnetic signals is also studied and their
reverberation is worked out and discussed. Furthermore, we show that a
Dirac-like monopole yields a (static) tangential electric field. We also
discuss some classical and quantum consequences of the field created by such a
monopole when acting upon an usual electric charge. In particular, we show that
at large distances, the dynamics of one single charged particle under the
action of such a potential and a constant (external) magnetic field as well,
reduces to that of one central harmonic oscillator, presenting, however, an
interesting angular sector which admits energy-eigenvalues. Among other
peculiarities, both sectors, the radial and the angular one, present
non-vanishing energy-eigenvalues for their lowest level. Moreover, those
associated to the angle are shown to respond to discrete shifts of such a
variable. We also raise the question whether the formation of bound states is
possible in the system.Comment: 17 pages, 2 figures. To appear in Phys. Rev.
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