Study of Beauty Hadron Decays into Pairs of Charm Hadrons

First observations of the decays A(b)(0) -> A(c)(+)D((s))(-) are reported using data corresponding to an integrated luminosity of 3 fb(-1) collected at 7 and 8 TeV center-of- ass energies in proton-proton collisions with the LHCb detector. In addition, the most precise measurement of the branching fraction B(B-s(0) -> D+Ds-) is made and a search is performed for the decays B-0((s)) -> A(c)(+)A(c)(-). The results obtained are B(A(b)(0) -> A(c)(+)D(-))/B(A(b)(0) -> A(c)(+)D(s)(-)) = 0.042 +/- 0.003 (stat) +/- 0.003 (syst), [B(A(b)(0) -> A(c)(+)D(s)(-))/B((B) over bar (0) -> D+Ds-)]/[B(A(b)(0) -> A(c)(+)pi(-))/B((B) over bar (0) -> D+pi(-))] = 0.96 +/- 0.02 (stat) +/- 0.06 (syst), B(B-s(0) -> D+Ds-)/B((B) over bar (0) -> D+Ds-) = 0.038 +/- 0.004 (stat) +/- (syst), B((B) over bar (0) -> A(c)(+)A(c)(-))/B((B) over bar (0) -> D+Ds-) A(c)(+)A(c)(-)) /B(B-s(0) -> D+Ds-) < 0.30[95% C.L.]. Measurement of the mass of the A(b)(0) baryon relative to the (B) over bar (0) meson gives M(A(b)(0)) ¿ M((B) over bar (0)) = 339.72 +/- 0.24 (stat) +/- 0.18 (syst) MeV/c(2). This result provides the most precise measurement of the mass of the A(b)(0) baryon to date

Study of beauty hadron decays into pairs of harm hadrons

First observations of the decays Λ0b→Λ+cD−(s) are reported using data corresponding to an integrated luminosity of 3  fb−1 collected at 7 and 8 TeV center-of-mass energies in proton-proton collisions with the LHCb detector. In addition, the most precise measurement of the branching fraction B(B0s→D+D−s) is made and a search is performed for the decays B0(s)→Λ+cΛ−c. The results obtained are B(Λ0b→Λ+cD−)/B(Λ0b→Λ+cD−s)=0.042±0.003(stat)±0.003(syst),[B(Λ0b→Λ+cD−s)B(B¯0→D+D−s)]/[B(Λ0b→Λ+cπ−)B(B¯0→D+π−)]=0.96±0.02(stat)±0.06(syst),B(B0s→D+D−s)/B(B¯0→D+D−s)=0.038±0.004(stat)±0.003(syst),B(B¯0→Λ+cΛ−c)/B(B¯0→D+D−s)&#60;0.0022[95%  C.L.],B(B0s→Λ+cΛ−c)/B(B0s→D+D−s)&#60;0.30[95%  C.L.]. Measurement of the mass of the Λ0b baryon relative to the B¯0 meson gives M(Λ0b)−M(B¯0)=339.72±0.24(stat)±0.18(syst)  MeV/c2. This result provides the most precise measurement of the mass of the Λ0b baryon to date

Effects of oral contraceptive pill use on vaginal flora and vaginal epithelium

The objective of this study was to examine the effect of oral contraceptive (OC) use on vaginal discharge, epithelium, and flora. Thirty women who planned to use OC for contraception were evaluated before and 2 months after the start of OC use. At both visits, genital symptoms and exposures were assessed by questionnaire; vaginal signs were assessed by speculum examination and colposcopy; vaginal microflora was evaluated by quantitative culture; and a vaginal biopsy was obtained for histopathologic evaluation. Variables were compared between the initial visit and after 2 months of OC use. It was found that OC use did not change the gross, colposcopic, or histologic appearance of the vaginal epithelium or characteristics of vaginal or cervical discharge. Vaginal flora essentially remained unchanged after 2 months of OC use, except that a small decrease occurred in the number of subjects with ≥10 5 colony forming units/mL of H 2O 2 producing Lactobacillus from 16 at baseline to 9 (p = 0.04) and in the total number of subjects with Ureaplasma urealyticum from 17 at baseline to 10 of 29 (p = 0.04). The results indicate minimal effect of OC use on the vaginal epithelium and vaginal and cervical discharge, and a small effect on vaginal flora

Influence of the Normal Menstrual Cycle on Vaginal Tissue, Discharge, and Microflora

The objective of this study was to examine genital tissue, vaginal fluid, and vaginal microbial flora at 3 phases of the menstrual cycle in asymptomatic women. Vaginal examinations were performed 3 times in 74 women: at the menstrual phase (days 1-5), the preovulatory phase (days 7-12), and the postovulatory phase (days 19-24). Flora of 50 women without bacterial vaginosis (BV) was analyzed separately from flora of 24 women with BV. The volume of vaginal discharge increased and the amount of cervical mucus decreased over the menstrual cycle. Among subjects without BV, the rate of recovery of any Lactobacillus changed little (range, 82% to 98%; P = .2); however, a small increase occurred in the rate of recovery of heavy (3+ to 4+ semiquantitative) growth of Lactobacillus over the menstrual cycle (P = .04). A linear decrease occurred in the rate of recovery of heavy growth of any non-Lactobacillus species, from 72% at days 1-5 to 40% at days 19-24 (P = .002). A linear decrease also occurred in the rate of recovery of Prevotella species, from 56% on days 1-5 to 28% on days 19-24 (P = .007), while a small linear increase occurred in the rate of recovery of Bacteroides fragilis (P = .05). Among subjects with BV, the only significant change was an increase in the rate of recovery of Lactobacillus, from 33% at days 1-5 to 54% at days 19-24 (P = .008). Among all subjects, the rate of recovery of heavy growth of Lactobacillus increased over the menstrual cycle and, in contrast, the concentration of non-Lactobacillus species tended to be higher at menses, which is evidence that the vaginal flora becomes less stable at this time