Complete Solving for Explicit Evaluation of Gauss Sums in the Index 2 Case

Let $p$ be a prime number, $q=p^f$ for some positive integer $f$, $N$ be a positive integer such that $\gcd(N,p)=1$, and let \k be a primitive multiplicative character of order $N$ over finite field \fq. This paper studies the problem of explicit evaluation of Gauss sums in "\textsl{index 2 case}" (i.e. f=\f{\p(N)}{2}=[\zn:\pp], where \p(\cd) is Euler function). Firstly, the classification of the Gauss sums in index 2 case is presented. Then, the explicit evaluation of Gauss sums G(\k^\la) (1\laN-1) in index 2 case with order $N$ being general even integer (i.e. N=2^{r}\cd N_0 where $r,N_0$ are positive integers and $N_03$ is odd.) is obtained. Thus, the problem of explicit evaluation of Gauss sums in index 2 case is completely solved

Influence du rayonnement ultraviolet (UV) sur la stabilité physico-chimique d’un dosimètre du radon : le CN-85

Les dosimètres de radon tels que des nitrates de cellulose connaissent souvent une dégradation sous l’action de certains facteurs physiques ou chimiques. Nous avons étudié le comportement du CN-85, détecteur solide de traces nucléaires (DSTN), en atmosphère tropicale très ensoleillée (photo-vieillissement naturel) et dans une enceinte SEPAP 12/24 (photo-vieillissement accéléré artificiel), avant son exposition à une source de particules alpha (Am-241). Les résultats ont montré des modifications chimiques du détecteur, aussi bien en accéléré qu’en naturel, entraînant un changement de coloration. L’étude comparée des deux modes de photo-vieillissement a permis de déterminer un facteur d’accélération du vieillissement de 2,5. L’irradiation aux particules alpha des détecteurs a montré une perte d’efficacité de 98 % après 40 heures d’exposition solaire, ce qui permet de considérer une durée limite d’utilisation du DSTN en atmosphère tropicale ne dépassant guère une semaine. Cette durée d’utilisation pourrait être prolongée à l’intérieur des habitations du fait d’une baisse des températures et de la luminosité

Low prevalence of lipodystrophy in HIV-infected Senegalese children on long-term antiretroviral treatment : the ANRS 12279 MAGGSEN Pediatric Cohort Study

Background: The long-term benefits of antiretroviral treatment (ART) are associated with metabolic complications, especially lipodystrophy, which has been well described among HIV-infected adults and children on ART in developed settings. Specifically, stavudine, and to a lesser extent zidovudine and protease inhibitors (PI), have been consistently implicated in the development of lipodystrophy. In 2006, following advice from the WHO, Senegal began phasing out stavudine from first-line ART. The objectives of this cross-sectional analysis are to assess and identify risk factors affecting the prevalence of lipodystrophy in Senegalese children and adolescents on long-term ART participating in a cohort study. Methods: Lipodystrophy was clinically assessed in two- to 18-year-old children on ART for at least six months and with no concurrent severe acute malnutrition. Risk factors for lipodystrophy were identified using stepwise multivariable logistic regression. Explanatory variables included clinical and personal data, immunovirologic status, and therapeutic history. Results: Overall, 254 children were assessed for lipodystrophy. The median age was 10.9 years (IQR: 8.1-142) and the median duration on ART was 54 months (32-84). Only 18% had been previously treated with stavudine, with a median treatment duration of 8 months (5-25). Ongoing treatment included 76% of children receiving zidovudine (median duration of 48 months (26-74)) and 27% receiving PI (lopinavir/ritonavir; median duration of 49 months (23-59)). Mild signs of lipodystrophy were observed in 33 children (13%): 28 with lipoatrophy, 4 with lipohypertrophy and one with combined type. Boys were more likely to present with lipoatrophy than girls (aOR: 4.3, 95% CI: 1.6-11.7). Children previously treated with stavudine for >= 1 year had a greater risk for lipoatrophy than those never exposed (3.8, 1.0-14.0), although the association was weak. There was no association between lipodystrophy and age or current or cumulative treatment with lopinavir/ritonavir or zidovudine. Conclusions: We report low prevalence of mild lipodystrophy in children and adolescents on long-term ART receiving a stavudine-sparing regimen. These findings are reassuring for clinicians in low-income settings where zidovudine is massively prescribed and lopinavir/ritonavir is the only widely available PI

The old man and the letter: repertoires of literacy and languaging in a modern multiethnic Gambian village

Recent developments mark a ‘human turn’ in sociolinguistics, i.e., a move away from languages as linguistic systems used by people, toward language or languaging as a sociolinguistic system performed by people. This article inscribes itself in that tradition and offers a micro-ethnographic analysis of a literacy event in rural Gambia. The incident relates to a letter that was ‘written’ by an old illiterate villager in the process of arranging a family member’s marriage. Although the event in itself is fairly insignificant and trivial, it is mobilised to gain an insight into the social and cultural organisation of literacy and languaging in this village. The old man’s letter is a typical moment of ‘grassroots literacy’ and is not ‘orthographic’ but ‘heterographic’ (reflecting more than one prescriptive regime) and ‘exographic’ (drawing on imported normativity). Local languaging here is not the sum of the local languages (Mandinka plus Jola plus Fula plus English) but is a complexly regimented repertoire in which different functions of language are distributed differently across languages and individuals