A search for the decay B+→K+ννˉB^+ \to K^+ \nu \bar{\nu}

We search for the rare flavor-changing neutral-current decay $B^+ \to K^+ \nu \bar{\nu}$ in a data sample of 82 fb$^{-1}$ collected with the {\sl BABAR} detector at the PEP-II B-factory. Signal events are selected by examining the properties of the system recoiling against either a reconstructed hadronic or semileptonic charged-B decay. Using these two independent samples we obtain a combined limit of ${\mathcal B}(B^+ \to K^+ \nu \bar{\nu})<5.2 \times 10^{-5}$ at the 90% confidence level. In addition, by selecting for pions rather than kaons, we obtain a limit of ${\mathcal B}(B^+ \to \pi^+ \nu \bar{\nu})<1.0 \times 10^{-4}$ using only the hadronic B reconstruction method.Comment: 7 pages, 8 postscript figures, submitted to Phys. Rev. Let

High-reflectivity broadband distributed Bragg reflector lattice matched to ZnTe

We report on the realization of a high quality distributed Bragg reflector with both high and low refractive index layers lattice matched to ZnTe. Our structure is grown by molecular beam epitaxy and is based on binary compounds only. The high refractive index layer is made of ZnTe, while the low index material is made of a short period triple superlattice containing MgSe, MgTe, and ZnTe. The high refractive index step of Delta_n=0.5 in the structure results in a broad stopband and the reflectivity coefficient exceeding 99% for only 15 Bragg pairs.Comment: 4 pages, 3 figure

EuFe2_2As2_2 under high pressure: an antiferromagnetic bulk superconductor

We report the ac magnetic susceptibility $\chi_{ac}$ and resistivity $\rho$ measurements of EuFe$_2$As$_2$ under high pressure $P$. By observing nearly 100% superconducting shielding and zero resistivity at $P$ = 28 kbar, we establish that $P$-induced superconductivity occurs at $T_c \sim$~30 K in EuFe$_2$As$_2$. $\rho$ shows an anomalous nearly linear temperature dependence from room temperature down to $T_c$ at the same $P$. $\chi_{ac}$ indicates that an antiferromagnetic order of Eu$^{2+}$ moments with $T_N \sim$~20 K persists in the superconducting phase. The temperature dependence of the upper critical field is also determined.Comment: To appear in J. Phys. Soc. Jpn., Vol. 78 No.

Improved measurement of CP asymmetries in B-0 ->(c(c)over-bar)K0((*)) decays

We present results on time-dependent CP asymmetries in neutral B decays to several CP eigenstates. The measurements use a data sample of about 227x10(6) Upsilon(4S)-> B (B) over bar decays collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. The amplitude of the CPasymmetry, sin2 beta in the standard model, is derived from decay-time distributions from events in which one neutral B meson is fully reconstructed in a final state containing a charmonium meson and the other B meson is determined to be either a B-0 or (0) from its decay products. We measure sin2 beta=0.722 +/- 0.040(stat)+/- 0.023(syst) in agreement with the standard model expectation

Data from: No additive genetic variance for tolerance to ethynylestradiol exposure in natural populations of brown trout (Salmo trutta)

One of the most common and potent pollutants of freshwater habitats is 17-alpha-ethynylestradiol (EE2), a synthetic component of oral contraceptives that is not completely eliminated during sewage treatment and that threatens natural populations of fish. Previous studies found additive genetic variance for the tolerance against EE2 in different salmonid fishes and concluded that rapid evolution to this type of pollution seems possible. However, these previous studies were done with fishes that are lake-dwelling and hence typically less exposed to EE2 than river-dwelling species. Here we test whether there is additive genetic variance for the tolerance against EE2 also in river-dwelling salmonid populations that have been exposed to various concentrations of EE2 over the last decades. We sampled 287 adult brown trout (Salmo trutta) from 7 populations that show much genetic diversity within populations, are genetically differentiated, and that vary in their exposure to sewage-treated effluent. In order to estimate their potential to evolve tolerance to EE2, we collected their gametes to produce 730 experimental families in block-wise full factorial in vitro fertilizations. We then raised 7,302 embryos singly in 2 mL containers each and either exposed them to 1 ng/L EE2 (an ecologically relevant concentration, i.e. 2 pg per embryo added in a single spike to the water) or sham-treated them. Exposure to EE2 increased embryo mortality, delayed hatching time, and decreased hatchling length. We found no population differences and no additive genetic variance for tolerance to EE2. We conclude that EE2 has detrimental effects that may adversely affect population even at a very low concentration, but that our study populations lack the potential for rapid genetic adaptation to this type of pollution. One possible explanation for the latter is that continuous selection over the last decades has depleted genetic variance for tolerance to this synthetic stressor

Composição centesimal e aceitação de lingüiça elaborada com reduzido teor de gordura e adicionada de concentrados protéicos de soro de leite Centesimal composition and acceptance of sausages produced with reduced tenor of fat and added of whey protein concentrates

Este trabalho objetivou avaliar a composição centesimal e aceitação de lingüiças de carne suína fabricadas com Concentrado Protéico do Soro (WPC) ou com concentrado protéico, com elevado teor de b-lactoglobulina, como substitutos da gordura. Foram realizados sete tratamentos, um grupo controle, contendo 20% de gordura, e seis tratamentos com reduzido teor de gordura, contendo diferentes níveis de adição de WPC ou de fração de b-lactoglobulina, a saber, três tratamentos com 10% de gordura e adição de três diferentes concentrações de WPC (0,2%, 0,5% e 1,0%) e três tratamentos com 10% de gordura e três diferentes níveis de concentrado protéico, com elevado teor de b-lactoglobulina (0,1%, 0,3% e 0,6%). O experimento foi realizado com cinco repetições, contendo todos os tratamentos. Foram realizadas análises em dois tempos de avaliação, um dia após a fabricação e após um período de sete dias de estocagem a aproximadamente 4&deg;C. Foram realizadas análises de proteína (g/100g), gordura (g 100g-1), umidade (g 100g-1), estimativa de valor calórico (kcal 100g-1) e análise sensorial. Os resultados dos teores de proteína, gordura e valor calórico apresentaram diferença (P&pound;0,05) entre o grupo controle e os demais tratamentos. Os resultados das análises de umidade e sensorial não apresentaram diferenças (P>0,05). As proteínas lácteas foram eficazes na substituição da gordura de lingüiças de carne suína, em todos os tratamentos realizados, atendendo às especificações do Regulamento Técnico de Identidade e Qualidade das Lingüiças do Ministério da Agricultura Pecuária e Abastecimento, mantendo a qualidade sensorial.<br>The objective of the research was to evaluate the composition and acceptance of pork sausages manufactured with whey protein concentrate (WPC) or with protein concentrate containing high level of b-lactoglobulin (hereof called b-lactoglobulin) as fat substitutes. Seven treatments were established, a control containing 20% of fat, and six containing different levels of WPC or b-lactoglobulin addition (three treatments containing 10% of fat and 0.2%, 0.5% or 1.0% of WPC, and three treatments containing 10% of fat and 0.1%, 0.3% or 0.6% of b-lactoglobulin). Each treatment was repeated in five batches, and the samples of each batch was evaluated the first and seventh day after processing and storage at 4&deg;C. The samples were analyzed for protein (g 100g-1), fat (g 100g-1), moisture content (g 100g-1), caloric value (kcal/g) and sensory analyses. The results of protein, fat and caloric value were different between the group control and the other treatments (P&pound;0.05). Additionally, the moisture content and sensory analyses results showed that there was no difference (P>0.05) for the different treatments used in this experiment. The protein concentrates were efficient for the fat substitution in pork sausages, in the treatment levels used in the current experiment, complying with the specifications of the Brazilian legal requirements