Com este experimento objetivou-se avaliar o potencial de cicatrização do óleo de semente de girassol associado ao ultrassom terapêutico em ratos (Rattus novergicus) com ferida cutânea induzida. ...Utilizou-se 24 ratos adultos da linhagem Wistar, machos, distribuídos aleatoriamente em quatro grupos de seis animais, onde no grupo I (controle) se realizou a aplicação de água destilada; no grupo II foi aplicado óleo de semente de girassol; no grupo III foi realizada uma intervenção com Ultrassom 3 MHz após a aplicação de óleo de semente de girassol e no grupo IV apenas a aplicação de ultrassom. De acordo com o teste F, foram encontradas evidências de diferenças significativas, ao nível de 1% de probabilidade, entre os tratamentos, com relação ao tempo médio de cicatrização, onde houve grande significância da diferença nos tempos de cicatrização do Grupo III em relação aos outros grupos. Concluiu-se, com a presente pesquisa que o ultrassom terapêutico favoreceu a permeabilidade do óleo de semente de girassol nas estruturas teciduais, contribuindo para o menor tempo de cicatrização em feridas cutâneas experimentais de ratos (Rattus novergicus).
Using data collected by the high-energy photoproduction experiment FOCUS at Fermilab we performed a Dalitz plot analysis of the Cabibbo favored decay D+→K−π+π+. This study uses 53653 Dalitz-plot ...events with a signal fraction of ∼97%, and represents the highest statistics, most complete Dalitz plot analysis for this channel. Results are presented and discussed using two different formalisms. The first is a simple sum of Breit–Wigner functions with freely fitted masses and widths. It is the model traditionally adopted and serves as comparison with the already published analyses. The second uses a K-matrix approach for the dominant S-wave, in which the parameters are fixed by first fitting Kπ scattering data and continued to threshold by Chiral Perturbation Theory. We show that the Dalitz plot distribution for this decay is consistent with the assumption of two-body dominance of the final state interactions and the description of these interactions is in agreement with other data on the Kπ final state.
We have performed a search for CPT violation in neutral charm meson oscillations. While flavor mixing in the charm sector is predicted to be small by the Standard Model, it is still possible to ...investigate CPT violation through a study of the proper time dependence of a CPT asymmetry in right-sign decay rates for D0→K−π+ and D0→K+π−. This asymmetry is related to the CPT violating complex parameter ξ and the mixing parameters x and y: ACPT∝(Reξ)y−(Imξ)x. Our 95% confidence level limit is −0.0068<(Reξ)y−(Imξ)x<0.0234. Within the framework of the Standard Model Extension incorporating general CPT violation, we also find 95% confidence level limits for the expressions involving coefficients of Lorentz violation of (−2.8<N(x,y,δ)(Δa0+0.6ΔaZ)<4.8)×10−16 GeV, (−7.0<N(x,y,δ)ΔaX<3.8)×10−16 GeV, and (−7.0<N(x,y,δ)ΔaY<3.8)×10−16 GeV, where N(x,y,δ) is the factor which incorporates mixing parameters x, y and the doubly Cabibbo-suppressed to Cabibbo-favored relative strong phase δ.
Using data from the FOCUS (E831) experiment, we have searched for T violation in charm meson decays using the four-body decay channels D0→K−K+π−π+, D+→KS0K+π−π+, and Ds+→KS0K+π−π+. The T violation ...asymmetry is obtained using triple-product correlations and assuming the validity of the CPT theorem. We find the asymmetry values to be ATviol(D0)=0.010±0.057(stat.)±0.037(syst.), ATviol(D+)=0.023±0.062(stat.)±0.022(syst.), and ATviol(Ds+)=−0.036±0.067(stat.)±0.023(syst.). Each measurement is consistent with no T violation. New measurements of the CP asymmetries for some of these decay modes are also presented.
Using data from the FOCUS (E831) experiment at Fermilab, we present a new measurement of the weak decay-asymmetry parameter αΛc in Λc+→Λπ+ decay. Comparing particle with antiparticle decays, we ...obtain the first measurement of the CP violation parameter A≡αΛc+αΛ¯cαΛc−αΛ¯c. We obtain αΛc=−0.78±0.16±0.19 and A=−0.07±0.19±0.24 where errors are statistical and systematic.
We present a search for a charmed pentaquark decaying strongly to D(∗)−p. Finding no evidence for such a state, we set limits on the cross-section times branching ratio relative to D∗− and D− under ...particular assumptions about the production mechanism.
We review genetic programming principles, their application to FOCUS data samples, and use the method to study the doubly Cabibbo suppressed decay
D
+
→
K
+
π
+
π
-
relative to its Cabibbo favored ...counterpart,
D
+
→
K
-
π
+
π
+
. We find that this technique is able to improve upon more traditional analysis methods. To our knowledge, this is the first application of the genetic programming technique to High Energy Physics data.
We present a search for a pentaquark decaying strongly to Ξ−π− in γN collisions at a center-of-mass energy up to 25 GeV/c2. Finding no evidence for such a state in the mass range of 1480 MeV/c2 to ...2400 MeV/c2, we set limits on the yield and on the cross section times branching ratio relative to Ξ∗(1530)0.
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