Measurement of the B0-anti-B0-Oscillation Frequency with Inclusive Dilepton Events

The $B^0$-$\bar B^0$ oscillation frequency has been measured with a sample of 23 million \B\bar B pairs collected with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we select events in which both B mesons decay semileptonically and use the charge of the leptons to identify the flavor of each B meson. A simultaneous fit to the decay time difference distributions for opposite- and same-sign dilepton events gives $\Delta m_d = 0.493 \pm 0.012{(stat)}\pm 0.009{(syst)}$ ps$^{-1}$.Comment: 7 pages, 1 figure, submitted to Physical Review Letter

Impact of Chlamydia trachomatis in the reproductive setting: British Fertility Society Guidelines for practice

Chlamydia trachomatis infection of the genital tract is the most common sexually transmitted infection and has a world-wide distribution. The consequences of infection have an adverse effect on the reproductive health of women and are a common cause of infertility. Recent evidence also suggests an adverse effect on male reproduction. There is a need to standardise the approach in managing the impact of C. trachomatis infection on reproductive health. We have surveyed current UK practice towards screening and management of Chlamydia infections in the fertility setting. We found that at least 90% of clinicians surveyed offered screening. The literature on this topic was examined and revealed a paucity of solid evidence for estimating the risks of long-term reproductive sequelae following lower genital tract infection with C. trachomatis. The mechanism for the damage that occurs after Chlamydial infections is uncertain. However, instrumentation of the uterus in women with C. trachomatis infection is associated with a high risk of pelvic inflammatory disease, which can be prevented by appropriate antibiotic treatment and may prevent infected women from being at increased risk of the adverse sequelae, such as ectopic pregnancy and tubal factor infertility. Recommendations for practice have been proposed and the need for further studies is identified

Measurement of the CP-Violating Asymmetry Amplitude sin2β\beta

We present results on time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurements use a data sample of about 88 million Y(4S) --> B Bbar decays collected between 1999 and 2002 with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We study 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 B0 or B0bar from its decay products. The amplitude of the CP-violating asymmetry, which in the Standard Model is proportional to sin2beta, is derived from the decay-time distributions in such events. We measure sin2beta = 0.741 +/- 0.067 (stat) +/- 0.033 (syst) and |lambda| = 0.948 +/- 0.051 (stat) +/- 0.017 (syst). The magnitude of lambda is consistent with unity, in agreement with the Standard Model expectation of no direct CP violation in these modes

Performance of various cassava clones in the dry savanna region of Nigeria

Cassava (Manihot esculenta Crantz) crop is widely known adapt to variable drought conditions. Due to the lack of adapted and high-yielding cultivars tolerant to the prevalent biotic and abiotic stresses, cassava is yet to find a wide and appropriate niche in the farming systems of the African dry savannas. Research aimed at improving adaptation to dry environments is under way. Field studies conducted at two lowland sites in the northern Guinea and Sudan savanna zones of Nigeria revealed a wide genetic variability in adaptation among African and introduced Latin American germplasm. Significant genotypic variability for stomatal response to dry weather fibrous root development, leaf stay-green ability, tuberous root yield and apparent water-use efficiency have been noted. Such variable mechanisms of adaptation associated with drought resistance are currently used as selection criteria in the IITA breeding programme to improve and sustain the cassava production in these dry savanna zones

Genotype environment interactions for cyanogenic potential in cassava

The distribution of the cyanogenic potential in cassava germplasm has been found to be a continuum from very low values to high levels. Within the same genotype, the cyanogenic potential is affected by the planting season; it is low when planted at the beginning of the rainy season, and high when planted at the end of the rainy season. Water stress is known to increase the cyanogenic potential. Recent findings indicate that the effects of water stress on cyanogenic potential are more complex than originally thought. A high ground water table with an associated low water stress to the developing cassava roots does not necessarily lead to lower cyanogenic potential. Excess water stress created by an above ground water table leads to higher cyanogenic potential. The location effect on cyanogenic potential is very pronounced. The cyanogenic potential of a genotype can increase up to five-fold when planted in a different location. The genotype-environment interactions are less pronounced but significant; some genotypes maintain the same cyanogenic potential ranking when planted in various agroecological zones, even though the absolute values of cyanogenic potential may be increased or decreased. These effects of the environment on cassava cyanogenic potential are explained using available knowledge on biosynthesis, regulation and translocation of cyanogenic glucosides