L’article analyse la gestion optimale des barrages hydroelectriques quand les apports naturels en eau suivent cycles previsibles. La regle de Hotelling qui determine trajectoire valeur l’eau stock doit s’appliquer facon cyclique compte tenu ruptures saisonnieres et besoins a satisfaire. Quand un est constitue, si contraintes capacite du reservoir ne sont pas liantes, il possible proceder arbitr...

The relationship between infrastructural development and the socioeconomic well-being raises interest in rural areas. It specifically examines road construction, potable water supply, of dwellers Bakassi Local Government Area Cross River State, Nigeria. study design is cross-sectional, using quantitative qualitative data from 420 respondents, with a multi-stage sampling technique. descriptive s...

This study applies a production function approach to value the groundwater recharge function of the Hadejia-Nguru wetlands in northern Nigeria. The groundwater recharge function supports dry season agricultural production which is dependent on groundwater abstraction for irrigation. Using survey data this paper first carries out an economic valuation of agricultural production, per hectare of i...

METHODS A large family is described in which mental retardation segregates as an X linked trait. Six affected males in three generations were studied by linkage and clinical examination. RESULTS Characteristic clinical features include short stature, prominent lower lip, small testes, muscle wasting of the lower legs, kyphosis, joint hyperextensibility, abnormal gait, tremor, and decreased fi...

Histiocytic sarcoma (HS) is a neoplasm derived from histiocytes. Its diagnosis was not clear until its immunohistochemistry profile was correctly established. Not much is known about its genetic properties. We report a case of a 48-year-old male patient whose bone marrow was almost completely occupied by monomorphic medium size neoplastic cellularity. Its immunohistochemical profile was CD68(+)...

A new framework is found for the compactification of supersymmetric string theory. It is shown that the massless spectra of Calabi–Yau manifolds of complex dimension Dcrit can be derived from noncritical manifolds of complex dimension 2k + Dcrit, k ≥ 0. These higher dimensional manifolds are spaces whose nonzero Ricci curvature is quantized in a particular way. This class is more general than t...

17-Ketosteroid reductase (17KSR), also known as 17 beta-hydroxysteroid dehydrogenase, catalyzes the reversible interconversion of estradiol to estrone and of androstenedione to testosterone. Using a recently cloned human placental 17KSR cDNA, we show that the 1.4-kilobase mRNA for this enzyme is detected only in tissues producing estrogens, and a 2.4-kilobase mRNA is detected in some estrogenic...

A moderately mentally retarded 3 year old boy showed minor anomalies including a prominent forehead and flat occiput, exophthalmos, large and prominent ears, high arched palate, umbilical hernia, sacral dimple, and irregular position of the toes. Cardiac sonography disclosed a chorda running through the left ventricle. Cytogenetic investigation of the family showed a balanced insertional transl...