A Report on Sickle Cell in Sierra Leone

Sierra Leone is thought to be one of the West African countries most affected by sickle cell disorders. Estimates state that one in four people carry the gene for sickle cell and between 1 to 2% of births are of children with the condition. Despite this, there has been a general public health and social neglect of the condition, so that prevalence is poorly understood and policy non-existent. This participatory qualitative research project, conducted in 2018 in two districts in the country, sought to understand both women’s experiences caring for children with the condition, as well as what the needs were of women who had the condition. The findings illustrated that a historical memory of the condition and its effects exists in the intergenerational memories and practices of people. This is important to learn from to combat stigmatisation of women and people who have the condition. However, past expertise and medical knowledge currently co-exist in isolation from each other, with access to proper healthcare unavailable in most parts of the country. This has led to an inability to get a correct medical diagnosis, no advice about how to live with the condition and an inability to access specialized medical and rehabilitative services. These failures in care have led to early deaths and disablement, with the result that the general public fear the condition. A neglect of reproductive justice and the relational implications for women with the condition was also apparent in the high number of deaths of women and infants with sickle cell. Lastly, due to the work of the voluntary and medical sector, there is increasing awareness in parents, schools and communities of how the total environment is crucial for holistic management of sickle cell conditions in a low- income country. However, it is women who are still mostly responsible for ensuring that their children access a better quality of life and women who still incur moral blame and shame for their ill-health and that of their children

Unitary evolution of perturbations of a two-dimensional black hole

We discuss massive scalar perturbations of a two-dimensional dilaton black hole. We employ a Pauli-Villars reqularization scheme to calculate the effect of the scalar perturbation on the Bekenstein-Hawking entropy. By concentrating on the dynamics of the scalar field near the horizon, we argue that quantum effects alter the effective potential. We calculate the two-point function explicitly and show that it exhibits Poincare recurrences.Comment: 11 page

Coupled oscillators with power-law interaction and their fractional dynamics analogues

The one-dimensional chain of coupled oscillators with long-range power-law interaction is considered. The equation of motion in the infrared limit are mapped onto the continuum equation with the Riesz fractional derivative of order $\alpha$, when $0<\alpha<2$. The evolution of soliton-like and breather-like structures are obtained numerically and compared for both types of simulations: using the chain of oscillators and using the continuous medium equation with the fractional derivative.Comment: 16 pages, 5 figure

Fractional dynamics of systems with long-range interaction

We consider one-dimensional chain of coupled linear and nonlinear oscillators with long-range power wise interaction defined by a term proportional to 1/|n-m|^{\alpha+1}. Continuous medium equation for this system can be obtained in the so-called infrared limit when the wave number tends to zero. We construct a transform operator that maps the system of large number of ordinary differential equations of motion of the particles into a partial differential equation with the Riesz fractional derivative of order \alpha, when 0<\alpha<2. Few models of coupled oscillators are considered and their synchronized states and localized structures are discussed in details. Particularly, we discuss some solutions of time-dependent fractional Ginzburg-Landau (or nonlinear Schrodinger) equation.Comment: arXiv admin note: substantial overlap with arXiv:nlin/051201

The joint evolutionary histories of Wolbachia and mitochondria in Hypolimnas bolina

Background. The interaction between the Blue Moon butterfly, Hypolimnas bolina, and Wolbachia has attracted interest because of the high prevalence of male-killing achieved within the species, the ecological consequences of this high prevalence, the intensity of selection on the host to suppress the infection, and the presence of multiple Wolbachia infections inducing different phenotypes. We examined diversity in the co-inherited marker, mtDNA, and the partitioning of this between individuals of different infection status, as a means to investigate the population biology and evolutionary history of the Wolbachia infections. Results. Part of the mitochondrial COI gene was sequenced from 298 individuals of known infection status revealing ten different haplotypes. Despite very strong biological evidence that the sample represents a single species, the ten haplotypes did not fall within a monophyletic clade within the Hypolimnas genus, with one haplotype differing by 5% from the other nine. There were strong associations between infection status and mtDNA haplotype. The presence of wBol1 infection in association with strongly divergent haplotypes prompted closer examination of wBol1 genetic variation. This revealed the existence of two cryptic subtypes, wBol1a and wBol1b. The wBol1a infection, by far the most common, was in strict association with the single divergent mtDNA haplotype. The wBol1b infection was found with two haplotypes that were also observed in uninfected specimens. Finally, the wBol2 infection was associated with a large diversity of mtDNA haplotypes, most often shared with uninfected sympatric butterflies. Conclusion. This data overall supports the hypothesis that high prevalence of male-killing Wolbachia (wBol1) in H. bolina is associated with very high transmission efficiency rather than regular horizontal transmission. It also suggests this infection has undergone a recent selective sweep and was introduced in this species through introgression. In contrast, the sharing of haplotypes between wBol2-infected and uninfected individuals indicates that this strain is not perfectly transmitted and/or shows a significant level of horizontal transmission

Evolution of Male-Killer Suppression in a Natural Population

Male-killing bacteria are widespread in arthropods, and can profoundly alter the reproductive biology of their host species. Here we detail the first case of complete suppression of a male killer. The nymphalid butterfly Hypolimnas bolina is infected with a strain of the bacterium Wolbachia, wBol1, which kills male host embryos in Polynesian populations, but does not do so in many areas of Southeast Asia, where both males and female adults are naturally infected, and wBol1-infected females produce a 1:1 sex ratio. We demonstrate that absence of male killing by wBol1 is associated with dominant zygotic suppression of the action of the male killer. Simulations demonstrate host suppressors of male-killer action can spread very rapidly, and historical data indicating the presence of male killing in Southeast Asia in the very recent past suggests suppressor spread has been a very recent occurrence. Thus, male killer/host interactions are much more dynamic than previously recognised, with rapid and dramatic loss of the phenotype. Our results also indicate that suppression can render male killers completely quiescent, leading to the conclusion that some species that do not currently express a male killer may have done so in the past, and thus that more species have had their biology affected by these parasites than previously believed

The N-terminal intrinsically disordered domain of mgm101p is localized to the mitochondrial nucleoid.

The mitochondrial genome maintenance gene, MGM101, is essential for yeasts that depend on mitochondrial DNA replication. Previously, in Saccharomyces cerevisiae, it has been found that the carboxy-terminal two-thirds of Mgm101p has a functional core. Furthermore, there is a high level of amino acid sequence conservation in this region from widely diverse species. By contrast, the amino-terminal region, that is also essential for function, does not have recognizable conservation. Using a bioinformatic approach we find that the functional core from yeast and a corresponding region of Mgm101p from the coral Acropora millepora have an ordered structure, while the N-terminal domains of sequences from yeast and coral are predicted to be disordered. To examine whether ordered and disordered domains of Mgm101p have specific or general functions we made chimeric proteins from yeast and coral by swapping the two regions. We find, by an in vivo assay in S.cerevisiae, that the ordered domain of A.millepora can functionally replace the yeast core region but the disordered domain of the coral protein cannot substitute for its yeast counterpart. Mgm101p is found in the mitochondrial nucleoid along with enzymes and proteins involved in mtDNA replication. By attaching green fluorescent protein to the N-terminal disordered domain of yeast Mgm101p we find that GFP is still directed to the mitochondrial nucleoid where full-length Mgm101p-GFP is targeted

Beyond data mining; towards "idea engineering"

Abstract—SE data mining tools can be reconfigured to define and explore the space of decisions made by a community. Index Terms—Data mining, software engineering, artificial intelligenc

Molecular Hydrogen in the Ring Nebula: Clumpy Photodissociation Regions

Article DOI: 10.1086/345911 Article Stable URL: http://www.jstor.org/stable/10.1086/345911We present a 0 .65 resolution H2 1-0 S(1) 2.122 mm image of the Ring Nebula (NGC 6720), which was taken with the Near Infrared Imager at the WIYN 3.5 m telescope on Kitt Peak. The high resolution of the H2 observation is sufficient to reveal the finer structure of the molecular material in this nebula. The morphology of the molecular emission is compared to that of the ionized emission from the Ring Nebula as seen by the Hubble Space Telescope (HST; He ii, [O iii], and [N ii]), and it is clear that the dark clumps seen by HST match the locations of clumpy H2 emission, suggesting that these clumps are similar to the cometary knots seen in the Helix Nebula. As with the Helix, the clumpy H2 emission from the main ring of the Ring Nebula is contained within the optically bright ionized nebula, implying that the molecular gas is shielded inside dense condensations. Comparison of the observed H2 average surface brightnesses for the Ring Nebula [(1.5 ergs cm 2 s 1 sr 1] with time-dependent models of the expected H2 0.5)#10 4 emission from planetary nebulae (PNe) shows that it is consistent with H2 excitation in photodissociation regions (PDRs), confirming previous suggestions. Comparison of the Ring Nebula H2 emission with a younger PN, NGC 2346, and an older PN, the Helix Nebula, suggests an evolution in H2 surface brightness consistent with the time-dependent PDR models. Moreover, the knots of molecular gas appear to become more isolated as the PN evolves, consistent with optical studies of knots in PNe.A. K. S. was supported by NASA JPL 961504 and NASA STI 7898.02-96A. A. K. S. and M. M. were supported by NSF CAREER award AST 97-33697

Bacterial and metabolic phenotypes associated with inadequate response to ursodeoxycholic acid treatment in primary biliary cholangitis

Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease with ursodeoxycholic acid (UDCA) as first-line treatment. Poor response to UDCA is associated with a higher risk of progressing to cirrhosis, but the underlying mechanisms are unclear. UDCA modulates the composition of primary and bacterial-derived bile acids (BAs). We characterized the phenotypic response to UDCA based on BA and bacterial profiles of PBC patients treated with UDCA. Patients from the UK-PBC cohort (n = 419) treated with UDCA for a minimum of 12-months were assessed using the Barcelona dynamic response criteria. BAs from serum, urine, and feces were analyzed using Ultra-High-Performance Liquid Chromatography-Mass Spectrometry and fecal bacterial composition measured using 16S rRNA gene sequencing. We identified 191 non-responders, 212 responders, and a subgroup of responders with persistently elevated liver biomarkers (n = 16). Responders had higher fecal secondary and tertiary BAs than non-responders and lower urinary bile acid abundances, with the exception of 12-dehydrocholic acid, which was higher in responders. The sub-group of responders with poor liver function showed lower alpha-diversity evenness, lower abundance of fecal secondary and tertiary BAs than the other groups and lower levels of phyla with BA-deconjugation capacity (Actinobacteriota/Actinomycetota, Desulfobacterota, Verrucomicrobiota) compared to responders. UDCA dynamic response was associated with an increased capacity to generate oxo-/epimerized secondary BAs. 12-dehydrocholic acid is a potential biomarker of treatment response. Lower alpha-diversity and lower abundance of bacteria with BA deconjugation capacity might be associated with an incomplete response to treatment in some patients