A fourteen-year review of breast pathology at a rural referral center in western Kenya

Background: Breast cancer has a low incidence in Africa compared with other continents. Of breast cancer reported in Africa, middle and eastern Africa is reported with the lowest incidence. In general, there is a paucity of information about breast cancer in Africa. Breast cancer evaluation and treatment is plagued with inadequate resource and screening facility throughout sub-Saharan Africa. Therefore, it is difficult to adequately assess incidence or prevalence without appropriate cancer or death registries. To our knowledge, no data exists for breast cancer treated in rural Kenya.Methods: Review of all surgical pathology reports was performed from January 31, 1993 to August 31, 2007 at Tenwek Hospital, a 300 bed referral center located in Bomet, Kenya. Records were searched for any breast specimen or specimen related to breast disease such as metastatic breast disease.Results: For the studied period, a total of 118 breast cancers were identified from pathology report records. Men accounted for 13 (11.02%) of all breast cancers. The average age for men was 69 years (std 10.6). The average age of women (n=105) was 51.2 years (std 15.6). The difference between the mean ages among men and women was statistically significant (p=0.000195). Grades were listed for only 55 of 118 specimens. Grade 3 was recorded in 61.8% (34/55). Women, aged 50 years or less, comprised 59.3% of all women recorded ages. In females, Grade 1 occurred in 7.1%, Grade 2 in 39.3%, and Grade 3 in 53.6%. Average age for Grade 1 histology is 37.5 years (std 2.1), Grade 2 average was 38.3 years (std 5.9) and Grade 3 average age was 40.8 years (std 5.7). The majority of males had IDC (12/13) with one case of NHL and melanoma of the breast

”I was meant to be able to do this”: women’s experiences of breastfeeding. A phenomenological study

Introduction. There is strong evidence demonstrating that human breastmilk provides complete nutrition for human infants. While the rate of initiation of breastfeeding in the UK has increased steadily over the last 25 years, rates of exclusive breastfeeding in the early weeks and months over the same time period have shown only marginal increases. Method. An interpretive phenomenological approach informed by the philosophy of Martin Heidegger was adopted. The aim was to understand women’s experience of breastfeeding. Women were recruited from one city in the East Midlands in the UK, where the prevalence of breastfeeding is decreasing. Potential participants were recruited via health visitors at the primary birth visit. Ethical approval was received from the university and NHS research ethics committees. Data were collected between three and six months after the birth of their youngest child and analysis was guided by interpretive phenomenological principles. Findings. The women were found to be ill-prepared for the realities of breastfeeding and, for most women, the shock of this experience was overwhelming. In particular there was a lack of understanding and preparation for common problems and a lack of awareness of newborn behaviour. Misunderstandings of newborn behaviour resulted in the women blaming infantfeeding behaviours, such as crying, wakeful states and cluster feeding, on the specific method of infant-feeding. Frequent feeding cues were overwhelming and the women felt overawed by the sense of responsibility. It also led them to question their ability to provide an adequate milk supply. Discussion. The extent to which inadequate preparation for breastfeeding had a negative impact on the breastfeeding experiences of women in this study was a surprise. Antenatal education should focus more on preparing women for the realities. Education and support for breastfeeding women need to encompass infant-feeding cues and infant behaviours

A loop-mediated isothermal amplification (LAMP) assay for the detection of Cryptotermes brevis West Indian drywood termite (Blattodea: Kalotermitidae)

Cryptotermes brevis is one of the most destructive invasive termites in the subtropics and tropics and is a common biosecurity intercept at the Australian border. Drywood termite species are cryptic and difficult to identify morphologically in situations when soldiers or imagos are unavailable. We developed a novel DNA based loop-mediated isothermal amplification (LAMP) assay to detect C. brevis and differentiate it from other drywood termites. Validated voucher specimens of 30 different drywood termite species were obtained from several insect collections from which DNA was extracted and amplified. The amplicons containing partial mitochondrial 16S rRNA were sequenced and a DNA database was created from which C. brevis LAMP primers were developed, optimized, and tested. The assay was assessed against a range of target and non-target species and found to be specific, successfully amplifying the target specimens of C. brevis in under 30 min. Amplification success was variable against C. brevis faecal pellets due to minute, unmeasurable or degraded DNA. This LAMP test is a new tool for the rapid detection of C. brevis that will enable faster and less destructive management of drywood termite infestations

Successful induction of ovulation and completed pregnancy using recombinant human luteinizing hormone and follicle stimulating hormone in a woman with Kallmann's syndrome

The induction of ovulation in women with hypogonado-trophic hypogonadism requires follicle stimulating hormone (FSH) for follicular growth and both FSH and luteinizing hormone (LH) to induce optimal follicular steroidogenesis. The development of human recombinant FSH and LH means that individually tailored doses of both hormones can be used with the aim of inducing unifollicular ovulation. This report describes the use of recombinant human FSH and LH for the induction of ovulation and conception in the second cycle of treatment, and subsequently a successfully completed pregnancy in a woman with Kallmann's syndrom

Electronic damping of molecular motion at metal surfaces

A method for the calculation of the damping rate due to electron-hole pair excitation for atomic and molecular motion at metal surfaces is presented. The theoretical basis is provided by Time Dependent Density Functional Theory (TDDFT) in the quasi-static limit and calculations are performed within a standard plane-wave, pseudopotential framework. The artificial periodicity introduced by using a super-cell geometry is removed to derive results for the motion of an isolated atom or molecule, rather than for the coherent motion of an ordered over-layer. The algorithm is implemented in parallel, distributed across both ${\bf k}$ and ${\bf g}$ space, and in a form compatible with the CASTEP code. Test results for the damping of the motion of hydrogen atoms above the Cu(111) surface are presented.Comment: 10 pages, 3 figure

Incorporation of Density Matrix Wavefunctions in Monte Carlo Simulations: Application to the Frustrated Heisenberg Model

We combine the Density Matrix Technique (DMRG) with Green Function Monte Carlo (GFMC) simulations. The DMRG is most successful in 1-dimensional systems and can only be extended to 2-dimensional systems for strips of limited width. GFMC is not restricted to low dimensions but is limited by the efficiency of the sampling. This limitation is crucial when the system exhibits a so-called sign problem, which on the other hand is not a particular obstacle for the DMRG. We show how to combine the virtues of both methods by using a DMRG wavefunction as guiding wave function for the GFMC. This requires a special representation of the DMRG wavefunction to make the simulations possible within reasonable computational time. As a test case we apply the method to the 2-dimensional frustrated Heisenberg antiferromagnet. By supplementing the branching in GFMC with Stochastic Reconfiguration (SR) we get a stable simulation with a small variance also in the region where the fluctuations due to minus sign problem are maximal. The sensitivity of the results to the choice of the guiding wavefunction is extensively investigated. We analyse the model as a function of the ratio of the next-nearest to nearest neighbor coupling strength. We observe in the frustrated regime a pattern of the spin correlations which is in-between dimerlike and plaquette type ordering, states that have recently been suggested. It is a state with strong dimerization in one direction and weaker dimerization in the perpendicular direction.Comment: slightly revised version with added reference

A Plaquette Basis for the Study of Heisenberg Ladders

We employ a plaquette basis-generated by coupling the four spins in a $2\times2$ lattice to a well-defined total angular momentum-for the study of Heisenberg ladders with antiferromagnetic coupling. Matrix elements of the Hamiltonian in this basis are evaluated using standard techniques in angular-momentum (Racah) algebra. We show by exact diagonalization of small ($2\times4$ and $2\times6$) systems that in excess of 90% of the ground-state probability is contained in a very small number of basis states. These few basis states can be used to define a severely truncated basis which we use to approximate low-lying exact eigenstates. We show how, in this low-energy basis, the isotropic spin-1/2 Heisenberg ladder can be mapped onto an anisotropic spin-1 ladder for which the coupling along the rungs is much stronger than the coupling between the rungs. The mapping thereby generates two distinct energy scales which greatly facilitates understanding the dynamics of the original spin-1/2 ladder. Moreover, we use these insights to define an effective low-energy Hamiltonian in accordance to the newly developed COntractor REnormalization group (CORE) method. We show how a simple range-2 CORE approximation to the effective Hamiltonian to be used with our truncated basis reproduces the low-energy spectrum of the exact $2\times6$ theory at the \alt 1% level.Comment: 12 pages with two postscript figure

Observation of Parity Violation in the Omega-minus -> Lambda + K-minus Decay

The alpha decay parameter in the process Omega-minus -> Lambda + K-minus has been measured from a sample of 4.50 million unpolarized Omega-minus decays recorded by the HyperCP (E871) experiment at Fermilab and found to be [1.78 +/- 0.19(stat) +/- 0.16(syst)]{\times}10^{-2}. This is the first unambiguous evidence for a nonzero alpha decay parameter, and hence parity violation, in the Omega-minus -> Lambda + K-minus decay.Comment: 10 pages, 7 figure

Perturbation Theory for Spin Ladders Using Angular-Momentum Coupled Bases

We compute bulk properties of Heisenberg spin-1/2 ladders using Rayleigh-Schr\"odinger perturbation theory in the rung and plaquette bases. We formulate a method to extract high-order perturbative coefficients in the bulk limit from solutions for relatively small finite clusters. For example, a perturbative calculation for an isotropic $2\times 12$ ladder yields an eleventh-order estimate of the ground-state energy per site that is within 0.02% of the density-matrix-renormalization-group (DMRG) value. Moreover, the method also enables a reliable estimate of the radius of convergence of the perturbative expansion. We find that for the rung basis the radius of convergence is $\lambda_c\simeq 0.8$, with $\lambda$ defining the ratio between the coupling along the chain relative to the coupling across the chain. In contrast, for the plaquette basis we estimate a radius of convergence of $\lambda_c\simeq 1.25$. Thus, we conclude that the plaquette basis offers the only currently available perturbative approach which can provide a reliable treatment of the physically interesting case of isotropic $(\lambda=1)$ spin ladders. We illustrate our methods by computing perturbative coefficients for the ground-state energy per site, the gap, and the one-magnon dispersion relation.Comment: 22 pages. 9 figure

An Improved Upper Bound for the Ground State Energy of Fermion Lattice Models

We present an improved upper bound for the ground state energy of lattice fermion models with sign problem. The bound can be computed by numerical simulation of a recently proposed family of deformed Hamiltonians with no sign problem. For one dimensional models, we expect the bound to be particularly effective and practical extrapolation procedures are discussed. In particular, in a model of spinless interacting fermions and in the Hubbard model at various filling and Coulomb repulsion we show how such techniques can estimate ground state energies and correlation function with great accuracy.Comment: 5 pages, 5 figures; to appear in Physical Review