Thermodynamics of AdS/QCD

We study finite temperature properties of four dimensional QCD-like gauge theories in the gauge theory/gravity duality picture. The gravity dual contains two deformed 5d AdS metrics, with and without a black hole, and a dilaton. We study the thermodynamics of the 4d boundary theory and constrain the two metrics so that they correspond to a high and a low temperature phase separated by a first order phase transition. The equation of state has the standard form for the pressure of a strongly coupled fluid modified by a vacuum energy, a bag constant. We determine the parameters of the deformation by using QCD results for $T_c$ and the hadron spectrum. With these parameters, we show that the phase transition in the 4d boundary theory and the 5d bulk Hawking-Page transition agree. We probe the dynamics of the two phases by computing the quark-antiquark free energy in them and confirm that the transition corresponds to confinement-deconfinement transition.Comment: 1+19 pages, 6 figures, references added, section 3 improve

Sexual vulnerability and HIV seroprevalence among the deaf and hearing impaired in Cameroon

<p>Abstract</p> <p>Background</p> <p>This quantitative cross-sectional study examines sexual behaviour of a target group of hearing-impaired persons in Yaounde, the capital city of the Republic of Cameroon. It measures their HIV prevalence to enable assessment of their sexual vulnerability and to help reduce the gap in existing HIV serology data among people with disabilities in general and the deaf in particular.</p> <p>Methods</p> <p>The snowball sampling procedure was adopted as an adequate approach to meet this hard-to-reach group. A total of 118 deaf participants were interviewed for the behavioural component, using sign language as a means of data collection, while 101 participants underwent HIV serology testing. Descriptive analyses were done for behavioural data with Epi info software, while sera were tested by health personnel, using rapid and confirmation test reagents.</p> <p>Results</p> <p>From the results, it was clear that the hearing impaired were highly involved in risky sexual practices, as observed through major sexual indicators, such as: age at first sexual intercourse; condom use; and knowledge of sexually transmitted infections and AIDS. Furthermore, it was noted that the HIV prevalence rate of the hearing impaired in the capital of Cameroon was 4%, close to the prevalence in the city's general population (4.7%).</p> <p>Conclusions</p> <p>Such results suggest that there is a need for in-depth behavioural research and serological studies in this domain to better understand the determinants of risky sexual behaviour among the hearing impaired, and to propose operational prevention approaches for this group.</p

Modeling growth performances, survival, and feed efficiency of four local chickens genetic types from Cameroon

Survival, feed efficiency and growth performances of four local breeds of chickens in West Cameroon (normally feathered NF, feathered tarsus FT, crested C and naked neck NN,) have been compared from hatch to 16 weeks, to determine which one could be improved by selection. Gompertz equation was used to fit growth curve of the four breeds. The normally feathered genotype was the more rustic, with a survival rate of 85.1%, i.e. 12 to 39% better than the other 3 breeds. The feathered tarsus type showed more rapid growth than NF, NN, and C genotypes. The FT hens had the highest weight gain at beginning (17.1 g.d-1), whereas the maximum gain at 16 weeks is observed in NN hens (26.1 g.d-1). Sexual dimorphism continuously increased between 0 and 16 weeks. Feed conversion ratio was significantly affected by sex, but neither by breed or breed by sex interaction. Evolution of growth rate with age was similar in the four groups, but significant differences of growth curve parameters were found among breeds and/or sexes. Estimated hatch weight was lower in C hens and higher in FT hens. Initial specific growth rates and asymptotic body weight were higher in males for all breeds. Age at maximum growth rate was lower for females. Finally, the maturation rate varied both with breed and sex. Taking into account survival, growth, and feed efficiency performances of the four breeds, the NF breed seems to be the most appropriate candidate to be used for meat production in Cameroon.Keywords: growth, modelling, local breed, chicken, Cameroo

Embrittlement analysis of ∑5[210]/(−1−20)∑5[210]/(−1−20) FeAl grain boundary in presence of defects:an ab initio study

Abstract Iron aluminide (FeAl) inter-metallic compounds are potential candidates for structural applications at high temperatures owing to their superior corrosion resistance, high temperature oxidation, low density and inexpensive material cost. However, the presence of defects can lead to reduction in the strength and ductility of FeAl-based materials. Here we present a density functional theory (DFT) study of the effect of the presence of defects including Fe and Al vacancies as well as H dopants at the substitutional and interstitial sites at a Embrittlement analysis of $\sum {{{{5}\left[ {{21}0} \right]} \mathord{\left/ {\vphantom {{{5}\left[ {{21}0} \right]} {\left( {\overline{1}\overline{2}0} \right)}}} \right.} {\left( {\overline{1}\overline{2}0} \right)}}}$ FeAl grain boundary in presence of defects : an ab initio study FeAl grain boundary focusing on the energetics. The plane wave pseudopotential code Vienna Ab initio Simulation Package (VASP) in the generalized gradient approximation (GGA) is used to carry out the computations. The formation energy calculations showed that intrinsic defects such as Fe and Al vacancies probably form at the GB, indicated by their negative formation energies. These vacancies can further form defect complexes with H impurities, indicated by lowered formation energies, compact bonds and charge gain of H atoms. Electronic structure analysis showed stronger hybridization of 1s orbitals of H with Fe and Al atoms, which leads to the stabilization of these defects resulting in degradation of material strength

C55 - Contrôle de qualité des comprimés de diclofénac de sodium 50 mg commercialisés à Yaoundé dans le circuit licite et illicite

Introduction : De nombreux médicaments sur le marché sont contrefaits et les anti-inflammatoires non stéroïdiens n’échappent pas à la règle. Ce travail avait pour objectif de contrôler la qualité des comprimés de diclofénac de sodium 50 mg commercialisés dans la ville de Yaoundé dans le circuit licite et illicite. Matériel et méthodes : Les échantillons ont été collectés par une méthode aléatoire simple dans le circuit licite et illicite. Les contrôles effectués comprenaient : le contrôle de l’emballage du médicament, le contrôle visuel, l’uniformité de masse, la friabilité, la désagrégation, l’identification et le dosage du principe actif des comprimés. Résultats : Un total de 24 échantillons de diclofénac de sodium a été collectés dont 12 prélevés du circuit licite, tous constitués des comprimés gastro-résistants, et 12 prélevés du circuit illicite 2 lots constitués de comprimés gastro-résistants, 5 lots de comprimés pelliculés et 5 lots de comprimés nus. Sur 24 échantillons analysés, 10 échantillons étaient conformes et provenaient tous du circuit licite. Tous les échantillons analysés étaient conformes à 100% en ce qui concerne le contrôle visuel, le contrôle de l’uniformité de masse et le contrôle de la friabilité. La totalité des échantillons analysés a révélé la présence du diclofénac de sodium. Les non-conformités observées sur l’ensemble des échantillons étaient de quatre types : le défaut de l’emballage des médicaments (2 échantillons sur 12 soit 16,67% dans le circuit licite versus 12 échantillons sur 12 soit 100% dans le circuit illicite), le défaut de la désagrégation des comprimés (1 échantillon sur 12 soit 8,33% dans le circuit licite versus 2 échantillons sur 12 soit 16,67% dans le circuit illicite), le sous dosage (0% dans le circuit licite versus 3 échantillons soit 25% dans le circuit illicite), le surdosage en principe actif (0% dans le circuit licite versus 1 échantillon soit 8,33% dans le circuit illicite). Conclusion : La non-conformité touche à la fois le circuit licite et illicite. La plupart des échantillons du secteur illicite sont non conformes. Toutes ces non-conformités exposent la population aux échecs thérapeutiques et la survenue de nouvelles pathologies

The Major Histocompatibility Complex B (MHC-B) and QTL Microsatellite Alleles of Favorable Effect on Antibody Response against the Newcastle Disease

The molecular typing and the indirect ELISA procedure were used to identify some alleles of favorable effect on the antibody response against the Newcastle disease virus (NDV). The NDV seroprevalence was 100.00% with 10.47% suspect and 89.63% positives. The protective level of ELISA antibody mean titre was 1409.43U/ml and 16.26% of the tested birds were considered tolerant. A total of 10 alleles of which 4 from the MHC-B Marker LEI0258 and 6 alleles from 5 QTL markers associated with resistance/tolerance against the NDV, namely LEI0070 (2 alleles) and only 1 allele for ADL0146, LEI0104, ADL0320 and ADL0304 respectively were shown to have a favorable effect on the antibody titre. The naked neck chicken was associated with high antibody response (1816.27 to 2227.55 U/ml) compare to the others (1409.48 to 1842.54 U/ml) and their phenotypic frequency was relatively higher (23.08) in the selected population compare to the sampled population (10.47) but, no MHC or QTL allele were private to the naked neck. These results suggest an evidence of genetic disease resistance within Cameroon native chicken populations and confirm the implication of the MHC-B in the immune response in general, and against the Newcastle disease virus in particular