Socio - demographic characteristics of HIV patients diagnosed at immunization centres in Calabar, South – south, Calabar, Nigeria

Introduction: The World Health Organization (WHO) estimated that 3.2 million children were living with Human Immunodeficiency Virus (HIV) at the end of 2013, mostly in sub- Saharan Africa. Socio- economic and demographic factors do not only affect viral transmission but also the success of preventive strategies and treatment.Objective: To determine the socio -demographic characteristics of mothers, and the relationship between maternal and HIV status of their infants attending immunization clinics in Calabar.Methods: Using multistage sampling method, 330 subjects were enrolled and screened from 63 immunization centres. The sociodemographic characteristic ofeach infant’s mother was documented. The results of Rapid test for mothers and Dried Blood Spots (DBS) results for infants were compared.Results: Of the 330 subjects recruited, 173 (52.4%) were males while 157(47.6%) were females. Mean age of the infants was 9.20 ± 3.1 weeks. Twenty four mothers and infants tested positive for HIV antibodies. After confirmatory tests using HIV Deoxyribosenucleic acid (DNA PCR), 14(58.3%) out of 24 antibody seropositive infants were infected. The transmission rate after confirmation was 58.3%.Conclusion: Parental education, social class and low maternal Antiretroviral drug (ARV) use were responsible for transmission. It is therefore recommended that health education on ARV use during antenatal period and HIV status of mother baby pair be done at immunization centres. HIV positive mothers and babies should be promptly referred for therapy.Keywords: Immunization, HIV, Infants, DNA PCR, PMTCT, AR

MATRIKS PANGKAT DAN KEPERIODIKANNYA DALAM ALJABAR MAX-PLUS

Dalam aljabar max-plus telah banyak dipelajari tentang sifat-sifat matriks.Salah satunya adalah keperiodikan suatu matriks yang tidak tereduksi. Telah diketahui pada aljabar maxplus bahwa barisan pangkat k A dalam Aljabar Max-Plus, dengan A adalah matriks persegi yang tidak tereduksi,  menjadi periodik setelah waktu terbatas T(A), dan periode akhirï§ sama dengan siklisitas grafkritis dari A. Dalam hubunganini dipelajari masalah komputasi dari matriks persegi yang berukuran nï‚´n yaitu jika diberikan k, hitung periodik pangkat r A dengan r  k(modï§ ) untuk r  T A . Ide utama adalah menggunakan penskalaan similaritas diagonal yang sesuai 1 A X AX  , yang disebut penskalaan visualisasi

The challenge of abandonment for the sustainable management of Palaearctic natural and semi-natural grasslands

Disturbance by biomass removal is a crucial mechanism maintaining the diversity of Palaearctic grasslands, which are unique biodiversity hotspots. The century-long traditional land use of mowing, grazing and burning, has been fundamentally changed in many parts of the Palaearctic. Due to socio-economic changes, large areas of former pastures and meadows have been abandoned, leading to a succession towards secondary scrublands or forest and the encroachment of competitor grass species, all leading to a decrease in biodiversity. Here we report the causes and consequences of the cessation of traditional grassland management regimes, provide strategies for reducing the impact of abandonment and consider these from the perspective of sustainability. We consider the possibilities for initiating sustainable management regimes in the contemporary socio-economic environment, and discuss the prospects and limitation of alternative management regimes in the conservation of grassland biodiversity. These themes are also the core topics of this Special Feature, edited by the EDGG. We hope that this Special Feature will encourage steps towards more sustainable strategies for the conservation of Palaearctic grasslands and the integration of the sustainability perspective into their conservation. © by Orsolya Valkó 2018.Peer reviewe

THE ENTIRE FACE IRREGULARITY STRENGTH OF A BOOK WITH POLYGONAL PAGES

A face irregular entire labeling is introduced by Baca et al. recently, as a modification of the well-known vertex irregular and edge irregular total labeling of graphs and the idea of the entire colouring of plane graph. A face irregular entire k-labeling ðœ†:ð‘‰âˆªð¸âˆªð¹â†’{1,2,⋯,ð‘˜} of a 2-connected plane graph ðº=(ð‘‰,ð¸,ð¹) is a labeling of vertices, edges, and faces of ðº such that for any two different faces ð‘“ and ð‘”, their weights ð‘¤ðœ†(ð‘“) and ð‘¤ðœ†(ð‘“) are distinct. The minimum 𑘠for which a plane graph ðº has a face irregular entire ð‘˜-labeling is called the entire face irregularity strength of ðº, denoted by ð‘’ð‘“ð‘ (ðº). This paper deals with the entire face irregularity strength of a book with ð‘š ð‘›-polygonal pages, where embedded in a plane as a closed book with ð‘›âˆ’sided external face

A physically based calving model applied to marine outlet glaciers and implications for the glacier dynamics

This is the published version, also available here: http://dx.doi.org/10.3189/002214310794457344.We present results from numerical ice-flow models that include calving criteria based on penetration of surface and basal crevasses, which in turn is a function of longitudinal strain rates near the glacier front. The position of the calving front is defined as the point where either (1) surface crevasses reach the waterline (model CDw), or (2) surface and basal crevasses penetrate the full thickness of the glacier (model CD). For comparison with previous studies, results are also presented for a height-above-buoyancy calving model. Qualitatively, both models CDw and CD produce similar behaviour. Unlike previous models for calving, the new calving criteria are applicable to both grounded termini and floating ice shelves and tongues. The numerical ice-flow model is applied to an idealized geometry characteristic of marine outlet glaciers. Results indicate that grounding-line dynamics are less sensitive to basal topography than previously suggested. Stable grounding-line positions can be obtained even on a reverse bed slope with or without floating termini. The proposed calving criteria also allow calving losses to be linked to surface melt and therefore climate. In contrast to previous studies in which calving rate or position of the terminus is linked to local water depth, the new calving criterion is able to produce seasonal cycles of retreat and advance as observed for Greenland marine outlet glaciers. The contrasting dynamical behaviour and stability found for different calving models suggests that a realistic parameterization for the process of calving is crucial for any predictions of marine outlet glacier change

The Pristine survey II: a sample of bright stars observed with FEROS

Extremely metal-poor (EMP) stars are old objects formed in the first Gyr of the Universe. They are rare and, to select them, the most successful strategy has been to build on large and low-resolution spectroscopic surveys. The combination of narrow- and broad band photometry provides a powerful and cheaper alternative to select metal-poor stars. The on-going Pristine Survey is adopting this strategy, conducting photometry with the CFHT MegaCam wide field imager and a narrow-band filter centred at 395.2 nm on the CaII-H and -K lines. In this paper we present the results of the spectroscopic follow-up conducted on a sample of 26 stars at the bright end of the magnitude range of the Survey (g<=15), using FEROS at the MPG/ESO 2.2 m telescope. From our chemical investigation on the sample, we conclude that this magnitude range is too bright to use the SDSS gri bands, which are typically saturated. Instead the Pristine photometry can be usefully combined with the APASS gri photometry to provide reliable metallicity estimates.Comment: AN accepte

The Eurasian Dry Grassland Group (EDGG) in 2016-2017

This report summarizes the activities and achievements of the Eurasian Dry Grassland Group (EDGG) from mid-2016 through to the end of 2017. During this period, the 13th Eurasian Grassland Conference took place in Sighişoara, Romania, and the 14th conference was held in Riga, Latvia. The 10th EDGG Field Workshop on Biodiversity patterns across a precipitation gradient in the Central Apennine mountains was conducted in the Central Apennines, Italy, this time in addition to multi-scale sampling of vascular plants, bryophytes and lichens, also including one animal group (leaf hoppers). Apart from the quarterly issues of its own electronic journal (Bulletin of the Eurasian Dry Grassland Group), EDGG also finalised five grassland-related Special Features/Issues during the past 1.5 years in the following international journals: Applied Vegetation Science, Biodiversity and Conservation, Phytocoenologia, Tuexenia and Hacquetia. Beyond that, EDGG facilitated various national and supra-national vegetationplot databases of grasslands and established its own specialised database for standardised multi-scale plot data of Palaearctic grasslands (GrassPlot). © by Stephen Venn 2018.Peer reviewe

The Eurasian Dry Grassland Group (EDGG) in 2015-2016

Peer reviewe

Accurate Fundamental Parameters or A, F, and G-type Supergiants in the Solar Neighbourhood

The following parameters are determined for 63 Galactic supergiants in the solar neighbourhood: effective temperature Teff, surface gravity log g, iron abundance log e(Fe), microturbulent parameter Vt, mass M/Msun, age t and distance d. A significant improvement in the accuracy of the determination of log g and, all parameters dependent on it, is obtained through application of van Leeuwens (2007) re-reduction of the Hipparcos parallaxes. The typical error in the log g values is now +-0.06 dex for supergiants with distances d < 300 pc and +-0.12 dex for supergiants with d between 300 and 700 pc; the mean error in Teff for these stars is +-120 K. For supergiants with d > 700 pc parallaxes are uncertain or unmeasurable, so typical errors in their log g values are 0.2-0.3 dex. A new Teff scale for A5-G5 stars of luminosity classes Ib-II is presented. Spectral subtypes and luminosity classes of several stars are corrected. Combining the Teff and log g with evolutionary tracks, stellar masses and ages are determined; a majority of the sample has masses between 4 Msun and 15 Msun and, hence, their progenitors were early to middle B-type main sequence stars. Using Fe ii lines, which are insensitive to departures from LTE, the microturbulent parameter Vt and the iron abundance log e(Fe) are determined from high-resolution spectra. The parameter Vt is correlated with gravity: Vt increases with decreasing log g. The mean iron abundance for the 48 supergiants with distances d < 700 pc is log e(Fe)=7.48+-0.09, a value close to the solar value of 7.45+-0.05, and thus the local supergiants and the Sun have the same metallicity.Comment: 12 pages, 9 figures. Will be published at MNRA

Light elements in massive single and binary stars

We highlight the role of the light elements (Li, Be, B) in the evolution of massive single and binary stars, which is largely restricted to a diagnostic value, and foremost so for the element boron. However, we show that the boron surface abundance in massive early type stars contains key information about their foregoing evolution which is not obtainable otherwise. In particular, it allows to constrain internal mixing processes and potential previous mass transfer event for binary stars (even if the companion has disappeared). It may also help solving the mystery of the slowly rotating nitrogen-rich massive main sequence stars.Comment: 10 pages, 8 figures, to appear in proc. IAU-Symp. 268. C. Charbonnel et al., eds