Chemistry of Chern-Simons Supergravity: reduction to a BPS kink, oxidation to M-theory and thermodynamical aspects

We construct a supersymmetric extension of the two dimensional Kaluza-Klein-reduced gravitational Chern-Simons term, and globally study its solutions, labelled by mass and U(1) charge c. The kink solution is BPS, and in an appropriate conformal frame all solutions asymptotically approach AdS. The thermodynamics of the Hawking effect yields interesting behavior for the specific heat and hints at a Hawking-Page-like transition at T_{critical} \sim c^{3/2}. We address implications for higher dimensions ("oxidation"), in particular D=3,4 and 11, and comment briefly on AdS/CFT aspects of the kink.Comment: 39 pages, 2 figures. v2: reference added, minor changes, typo

Supersymmetric black holes in 2D dilaton supergravity: baldness and extremality

We present a systematic discussion of supersymmetric solutions of 2D dilaton supergravity. In particular those solutions which retain at least half of the supersymmetries are ground states with respect to the bosonic Casimir function (essentially the ADM mass). Nevertheless, by tuning the prepotential appropriately, black hole solutions may emerge with an arbitrary number of Killing horizons. The absence of dilatino and gravitino hair is proven. Moreover, the impossibility of supersymmetric dS ground states and of nonextremal black holes is confirmed, even in the presence of a dilaton. In these derivations the knowledge of the general analytic solution of 2D dilaton supergravity plays an important role. The latter result is addressed in the more general context of gPSMs which have no supergravity interpretation. Finally it is demonstrated that the inclusion of non-minimally coupled matter, a step which is already nontrivial by itself, does not change these features in an essential way.Comment: 30 pages, LaTeX, v2: mayor revision (rearranged title, shortened abstract, revised introduction, inserted section from appendix to main text, added subsection with new material on non-SUGRA gPSMs, added clarifying remarks at some places, updated references); v3: corrected minor misprints, added note with a new referenc

Comment on: Reply to comment on `Perfect imaging without negative refraction'

Whether or not perfect imaging is obtained in the mirrored version of Maxwell's fisheye lens is debated in the comment/reply sequence [Blaikie-2010njp, Leonhardt-2010njp] discussing Leonhardt's original paper [Leonhardt-2009njp]. Here we show that causal solutions can be obtained without the need for an "active localized drain", contrary to the claims in [Leonhardt-2010njp].Comment: v2 (added MEEP ctl file), v3 (publisher statement

Composição proximal em filés, rendimento de carcaça e de cortes de jundiá (rhamdia quelen) alimentados com rações contendo diferentes óleos vegetais.

Este trabalho teve por objetivos avaliar a influência de óleos vegetais no desenvolvimento corporal de jundiá (Rhamdia quelen, Heptapteridae) e sua relação com o rendimento de carcaça, partes comestíveis e composição química do filé. Testaram-se seis rações com 32% de proteína bruta, sendo avaliados óleos de arroz, canola ou soja com 5 e 10% de inclusão durante 90 dias. Foram utilizados 180 peixes (peso inicial=71±0,81g) distribuídos ao acaso em 18 caixas de 280L (10 peixes/caixa) em um sistema de recirculação de água, com temperatura controlada (25,9±0,9ºC). Não houve diferenças para os parâmetros produtivos entre os tratamentos testados ao final do experimento (P<0,05). Os peixes alimentados com maiores níveis de óleo nas dietas depositaram maior porcentagem de gordura no filé. Conclui-se que os óleos de canola, arroz e soja utilizados como alternativas em dietas na recria de jundiá proporcionam bom rendimento de carcaça e de partes comestíveis. E, as rações contendo óleo de canola possibilitam menor deposição de gordura no filé de juvenis de jundiá em nível de 5%

Graded Poisson-Sigma Models and Dilaton-Deformed 2D Supergravity Algebra

Fermionic extensions of generic 2d gravity theories obtained from the graded Poisson-Sigma model (gPSM) approach show a large degree of ambiguity. In addition, obstructions may reduce the allowed range of fields as given by the bosonic theory, or even prohibit any extension in certain cases. In our present work we relate the finite W-algebras inherent in the gPSM algebra of constraints to algebras which can be interpreted as supergravities in the usual sense (Neuveu-Schwarz or Ramond algebras resp.), deformed by the presence of the dilaton field. With very straightforward and natural assumptions on them --like demanding rigid supersymmetry in a certain flat limit, or linking the anti-commutator of certain fermionic charges to the Hamiltonian constraint-- in the ``genuine'' supergravity obtained in this way the ambiguities disappear, as well as the obstructions referred to above. Thus all especially interesting bosonic models (spherically reduced gravity, the Jackiw-Teitelboim model etc.)\ under these conditions possess a unique fermionic extension and are free from new singularities. The superspace supergravity model of Howe is found as a special case of this supergravity action. For this class of models the relation between bosonic potential and prepotential does not introduce obstructions as well.Comment: 22 pages, LaTeX, JHEP class. v3: Final version, to appear in JHE

Tillage system effect on the epidemic of soybean brown spot.

Six field experiments were carried out during the summers of 1997 to 2003 to evaluate disease progress of soybean brown spot caused by Septoria glycines considering two tillage systems, conventional and no-tillage (wheat was cultivated during winter in all plots). Two logistic models were fitted to the disease progress data: (i) a logistic model with constant disease progress rate r [y=1/(1+(1/y0-1)exp(-rt)), where y0 is the initial disease level at time t=0] and (ii) a logistic model with an exponentially increasing progress rate r(t)=r0 ebt [y=1/(1+(1/y0-1) exp(r0/b(1-ebt))), where r0 is the initial progress rate at time t=0, b the rate increasing parameter, and y0 again the initial disease level]. The logistic model with constant rate underestimated disease incidence on the first disease assessment in nine out of twelve epidemics. The logistic model with an increasing rate gave a better fit to all disease progress curves (R2 between 0.90 and 0.99; no pattern in the residuals). According to this model, y0 was in most cases (four out of six) significantly smaller in the plots with no-tillage compared with conventional tillage, but no differences were detected in the initial rate parameter r0 and the rate increasing parameter b (with one exception). It is proposed that these results are due to higher susceptibility of old leaflets compared with young leaflets, as demonstrated by artificial inoculation: In four laboratory experiments the mean brown spot severity was 16.7 % on old leaflets but only 3.9 % on young leaflets

On the quest for unification - simplicity and antisimplicity

The road towards unification of elementary interactions is thought to start on the solid ground of a universal local gauge principle. I discuss the different types of bosonic gauge symmetries in gravitational and nongravitational (standard model) interactions and their extensions both fermionic, bosonic and with respect to space-time dimensions. The apparently paradoxical size and nature of the cosmological constant is sketched, which at first sight does not readily yield a clue as to the envelopping symmetry structure of a unified theory. Nevertheless a tentative outlook is given encouraging to proceed on this road.Comment: 29 pages, 4 figure

Desempenho de jundiás alimentados com fontes proteicas submetidas ou não a tratamento para remoção de antinutrientes.

O objetivo deste trabalho foi avaliar o desempenho de jundiás alimentados com diferentes fontes proteicas de origem vegetal, submetidas ou não a tratamento químico (lavagem com solução ácida, seguida de lavagem com etanol) para a remoção de fatores antinutricionais.Organizado por: Sílvio Ricardo Maurano; AQUACIÊNCIA 2012

Classical and Quantum Integrability of 2D Dilaton Gravities in Euclidean space

Euclidean dilaton gravity in two dimensions is studied exploiting its representation as a complexified first order gravity model. All local classical solutions are obtained. A global discussion reveals that for a given model only a restricted class of topologies is consistent with the metric and the dilaton. A particular case of string motivated Liouville gravity is studied in detail. Path integral quantisation in generic Euclidean dilaton gravity is performed non-perturbatively by analogy to the Minkowskian case.Comment: 27 p., LaTeX, v2: included new refs. and a footnot

Estudos sobre a nutrição mineral do feijão macassar (Vigna sinensis (L) Endl.). V: chave para a identificação de deficiências minerais

Symptoms of deficiency of macro and micronutrients were induced in Vigna sinensis by growing two cultivars in nutrient solution under the necessary treatments. Results there of were used to prepare a key which could be used in the visual diagnosis of mineral deficiencies. As a rule, the information obtained is in agreement with result found in the literature for other legumes. It is noteworthy, however, that symptoms of Mo and Zn first showed up in older leaves.É apresentada uma chave para identificação visual das deficiências de macro e de micronutrientes em Vigna sinensis