The Lyman-alpha forest and WMAP year three

A combined analysis of Cosmic Microwave Background (CMB) and Lyman-a forest data allows to constrain the matter power spectrum from small scales of about 1 Mpc/h all the way to the horizon scale. The long lever arm and complementarity provided by such an analysis has previously led to a significant tightening of the constraints on the shape and the amplitude of the power spectrum of primordial density fluctuations. We present here a combined analysis of the WMAP three year results with Lyman-a forest data. The amplitude of the matter power spectrum sigma_8 and the spectral index ns inferred from the joint analysis with high resolution Lyman-a forest data and low resolution Lyman-a forest data as analyzed by Viel & Haehnelt (2006) are consistent with the new WMAP results to within 1 sigma. The joint analysis with the mainly low resolution data as analysed by McDonald et al. (2005) suggests a value of sigma_8 which is ~ 2 sigma higher than that inferred from the WMAP three year data alone. The joint analysis of the three year WMAP and the Lyman-a forest data also does not favour a running of the spectral index. The best fit values for a combined analysis of the three year WMAP data, other CMB data, 2dF and the Lyman-a forest data are (sigma_8, ns) = (0.78\pm 0.03,0.96 \pm 0.01).Comment: 5 pages, 4 figs, 2 tables. MNRAS letters in pres

Improving CMB non-Gaussianity estimators using tracers of local structure

Local non-Gaussianity causes correlations between large scale perturbation modes and the small scale power. The large-scale CMB signal has contributions from the integrated Sachs Wolfe (ISW) effect, which does not correlate with the small scale power. If this ISW contribution can be removed, the sensitivity to local non-Gaussianity is improved. Gravitational lensing and galaxy counts can be used to trace the ISW contribution; in particular we show that the CMB lensing potential is highly correlated with the ISW signal. We construct a nearly-optimal estimator for the local non-Gaussianity parameter \fnl and investigate to what extent we can use this to decrease the variance on {\fnl}. We show that the variance can be decreased by up to $20\%$ at Planck sensitivity using galaxy counts. CMB lensing is a good bias-independent ISW tracer for future more sensitive observations, though the fractional decrease in variance is small if good polarization data is also available.Comment: 8 pages, 3 figures. Comments welcom

\u3cem\u3ePlasmodium falciparum\u3c/em\u3e SSB Tetramer Binds Single-Stranded DNA Only in a Fully Wrapped Mode

The tetrameric Escherichia coli single-stranded DNA (ssDNA) binding protein (Ec-SSB) functions in DNA metabolism by binding to ssDNA and interacting directly with numerous DNA repair and replication proteins. Ec-SSB tetramers can bind ssDNA in multiple DNA binding modes that differ in the extent of ssDNA wrapping. Here, we show that the structurally similar SSB protein from the malarial parasite Plasmodium falciparum (Pf-SSB) also binds tightly to ssDNA but does not display the same number of ssDNA binding modes as Ec-SSB, binding ssDNA exclusively in fully wrapped complexes with site sizes of 52–65 nt/tetramer. Pf-SSB does not transition to the more cooperative (SSB)35 DNA binding mode observed for Ec-SSB. Consistent with this, Pf-SSB tetramers also do not display the dramatic intra-tetramer negative cooperativity for binding of a second (dT)35 molecule that is evident in Ec-SSB. These findings highlight variations in the DNA binding properties of these two highly conserved homotetrameric SSB proteins, and these differences might be tailored to suit their specific functions in the cell

<Material>Japan\u27s Official Development Assistance : Promoting Sustainable Development

Official Development Assistance (ODA) is a technical term defined by the OECD. One of the main categories of Japan ODA is bilateral grants which facilitate transfer of technology, skills and knowledge. These transfers, though complex, are a necessary requirement of the technology transfer cycle necessitated by social challenges brought about by new technology. Therefore, it is essential for provision of new technology to be associated with continued professional interaction and training. Developing countries continue to rely on ODA due to various country specific social and developmental setbacks. Therefore, the technology transfer process should be country specific, not based on any preset models or ideologies, and should have support from all the relevant stakeholders. The author is currently undergoing technical or counterpart training facilitated by the Japan International Co-operation Agency (JICA) and Kawasaki University of Medical Welfare. This paper was written to highlight the importance of capacity strengthening to both institutions and individuals. The case for Kenya Medical Research Institute (KEMRI) is to provide encouragement to general public and support to its staff for this kind of successful form of ODA towards sustainable development

Into the realm of social capital for adolescents: a latent profile analysis

Background Recent reports of increasing prevalence of frequent health complaints and mental health problems among adolescents call for directing more attention on determinants of adolescent health. The relationship between health and social capital has gained increased attention since the early 2000’s and research at review level confirms the importance of social capital for health outcomes, despite methodological heterogeneity. The aim of this study was to identify distinct profiles of family, school and peer social capital in a nationally representative sample of adolescents and to explore health outcomes in those profiles. Method Cross-sectional data from the Swedish Health Behaviour of School-aged Children 2013/14 was used for this study. The analytical sample consisted of 7,804 adolescents aged 11-, 13- and 15-years. Items representing sense of belonging and emotional support were assessed in three contexts; family, school and among peers. Latent profile analyses (LPA) were run to determine social capital profiles. Health outcomes included frequent health complaints and life satisfaction, while socioeconomic status and genders were included as predictors. Results The results show that five distinct profiles best represent the data for 11- and 15-year olds, while a four-profile model was optimal for 13-year olds. Some profiles were recurrent between age groups but unique profiles were also found. Health outcomes were significantly different between profiles depending on levels of social capital in the different contexts. Conclusions This study provides novel insight into how social capital co-occurs among adolescents within the contexts of family, school and peers and how this translates into differences in health outcomes. The national representativeness of the sample increases the implications of the results and contributes to meaningful insights that help explain the interactions of social capital in multiple contexts, complementing what is previously known about the relationship with adolescent health. © 2019 Ahlborg et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Properties and use of CMB power spectrum likelihoods

Fast robust methods for calculating likelihoods from CMB observations on small scales generally rely on approximations based on a set of power spectrum estimators and their covariances. We investigate the optimality of these approximation, how accurate the covariance needs to be, and how to estimate the covariance from simulations. For a simple case with azimuthal symmetry we compare optimality of hybrid pseudo-C_l CMB power spectrum estimators with the exact result, indicating that the loss of information is not negligible, but neither is it enough to have a large effect on standard parameter constraints. We then discuss the number of samples required to estimate the covariance from simulations, with and without a good analytic approximation, and assess the use of shrinkage estimators. Finally we discuss how to combine an approximate high-ell likelihood with a more exact low-ell harmonic-space likelihood as a practical method for accurate likelihood calculation on all scales.Comment: 15 pages, 11 figures; updated to match version accepted by PR

Prodrugs of antiviral phosphonates

Phosphonoformate and phosphonoacetate are effective antiviral agents, however they are charged at physiological pH and as such penetration into cells and diffusion across the blood-brain bamer is limited. In an attempt to increase the lipophilicity and improve the transport properties of these molecules, prodrugs were synthesised and their stabilities and reconversion to the parent compound subsequently investigated by the techniques of 31P nuclear magnetic resonance spectroscopy and high performance liquid Chromatography. A series of 4-substituted dibenzyl (methoxycarbonyl)phosphonates were prepared and found to be hydrolytically unstable giving predominantly the diesters, benzyl (methoxycarbonyl)phosphonates. This instability arose from the electron-withdrawing effect of the carbonyl group promoting nucleophilic attack at phosphorus. It was possible to influence the mechanism and, to some extent, the rate of hydrolysis of the phosphonoformate triesters to the diesters by varying the electronic nature of the substituent in the 4-position of the aromatic ring. Strongly electron-withdrawing groups increased the sensitivity of phosphorus to nucleophilic attack, thus promoting P-O .bond cleavage and rapid hydrolysis. Conversely, weakly electron-withdrawing substituents encouraged C-O bond fission, presumably through resonance stabilisation of the benzyl carbonium ion. The loss of the protecting group on phosphorus was in competition with nucleophilic attack at the carbonyl group, resulting in P-C bond cleavage with dibenzyl phosphite formation. The high instability and P-C bond fission make triesters unsuitable prodrug forms of phosphonoformate. A range of chemically stable triesters of phosphonoacetate were synthesised and their bioactivation investigated. Di(benzoyloxymethyl) (methoxycarbonylmethyl)phosphonates degraded to the relevant benzoyloxymethyl (methoxycarbonylmethyl)phosphonate in the presence of esterase. The enzymatic activation was restricted to the removal of only one protecting group from phosphorus, most likely due to the close proximity of the benzoyloxy ester function to the anionic charge on the diester. However, in similar systems di(4-alkanoyloxybenzyl) (methoxycarbonylmethyl)phosphonates degraded in the presence of esterase with the loss of both protecting groups on phosphorus to give the monoester, (methoxycarbonylmethyl)phosphonate, via the intermediary of the unstable 4-hydroxy benzyl esters. The methoxycarbonyl function remained intact. The rate of enzymatic hydrolysis and subsequent removal of the protecting groups on phosphorus was dependent on the nature of the alkanoyl group and was most rapid for the 4-nbutanoyloxybenzyl and 4-iso-butanoyloxybenzyl esters of phosphonoacetate. This provides a strategy for the design of a prodrug with sufficient stability in plasma to reach the central nervous system in high concentration, wherein rapid metabolism to the active drug by brain-associated enzymes occurs

Numerical wave optics and the lensing of gravitational waves by globular clusters

We consider the possible effects of gravitational lensing by globular clusters on gravitational waves from asymmetric neutron stars in our galaxy. In the lensing of gravitational waves, the long wavelength, compared with the usual case of optical lensing, can lead to the geometrical optics approximation being invalid, in which case a wave optical solution is necessary. In general, wave optical solutions can only be obtained numerically. We describe a computational method that is particularly well suited to numerical wave optics. This method enables us to compare the properties of several lens models for globular clusters without ever calling upon the geometrical optics approximation, though that approximation would sometimes have been valid. Finally, we estimate the probability that lensing by a globular cluster will significantly affect the detection, by ground-based laser interferometer detectors such as LIGO, of gravitational waves from an asymmetric neutron star in our galaxy, finding that the probability is insignificantly small.Comment: To appear in: Proceedings of the Eleventh Marcel Grossmann Meetin