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Showing papers by "Tunis University published in 1991"


Journal ArticleDOI
TL;DR: Nearly all sickle cell anemia patients carried the beta S mutation on a chromosome with haplotype 19 (or Benin) and all had severe anemia with sickling complications, which explains the need for regular blood transfusions in the thalassemia major and S-beta-thalassemia patients.
Abstract: We analyzed the mutations present in 19 patients with beta-thalassemia major, in 11 patients with Hb S-beta-thalassemia, and the beta S haplotypes of 34 patients with sickle cell anemia. The study included 84 relatives. Dot-blot analysis of amplified DNA with various specific oligonucleotide probes identified 11 different known beta-thalassemia mutations and frameshifts; a new frameshift at codons 25/26 (+T) was detected through sequencing of amplified DNA. The common beta-thalassemia mutations at codon 39 (C----T) and at IVS-I-110 (G----A) were also most prevalent among the Tunisian patients, while the milder T----C mutation at IVS-I-6 was not found. All mutations cause a beta 0-thalassemia or a severe beta + -thalassemia [T----A at -30; IVS-I-5 (G----A); IVS-I-110 (G----A)] which explains the need for regular blood transfusions in the thalassemia major and S-beta-thalassemia patients. Nearly all sickle cell anemia patients carried the beta S mutation on a chromosome with haplotype 19 (or Benin) and all had severe anemia with sickling complications. Identification of the beta S haplotype was through dot-blot analysis with oligonucleotide probes that detect mutations in the G gamma and A gamma promoter sequences, specific for this haplotype.

55 citations



Journal ArticleDOI
TL;DR: A statistical study which evaluates the impact of a number of factors on programmer productivity and limits its attention to controllable facts, i.e., factors that a software manager can determine at will during the software development process.

17 citations


Journal ArticleDOI
TL;DR: The distribution of 1,198 Malmö alleles was examined in 822 men from 16 indigenous populations and 188 women from 7 of the ethnic groups, consistent with the European origin of the 'B' allele when the population was small and outward spread.
Abstract: The distribution of 1,198 Malmo alleles was examined in 822 men from 16 indigenous populations and 188 women from 7 of the ethnic groups. Subjects were from several European countries, the Mediterranean, East Asia, and the USA (Anglo- and African-Americans). The frequencies of the rarer (Malmo B) allele were approximately equal across Europe, the highest frequencies (0.36) being in the French and Anglo-Americans; no population was observed with clearly the highest frequency. They diminished slightly at moderate distances from Europe (Tunisia, Ethiopia) and greatly at longer distances (East Asia and West Africa). In Orientals, the frequencies ranged from 0.07 (East Indians) to 0.03 (the Chinese) and from 0.0 to 0.15 in African-Americans. Assuming selective neutrality, the data are consistent with the European origin of the ‘B’ allele when the population was small and outward spread.

13 citations


Proceedings ArticleDOI
15 Oct 1991
TL;DR: An empirical study of the management of software maintenance is presented, based on completion of an earlier study, which covers a total of sixty surveys, taken in 1988 and 1989.
Abstract: An empirical study of the management of software maintenance is presented, based on completion of an earlier study. The survey at hand has been conducted by means of live interviews with analysts and software managers, using a translated version of B.P. Lientz and E.B. Swanson's (1978) survey form (slightly adjusted at times to take into account a difference of data processing culture). The authors accumulated a total of 150 completed survey forms, properly distributed on the various sectors of the Tunisian data processing industry. For the sake of comparison or confirmation, the authors mention a similar study that was carried out by one of the authors with some companies in Algeria. This study covers a total of sixty surveys, taken in 1988 and 1989. The final results are presented. The issues discussed are scale of effect issues, organizational issues, productivity technique issues and problem area issues. >

7 citations


Journal ArticleDOI
TL;DR: In this paper, the authors follow Pudney in stressing the usefulness of a description of the separable structure of preferences underlying an estimated model, and propose a non-iterative method for the production of such a description.
Abstract: In empirical demand analysis separability restrictions are usually imposed as maintained hypotheses. The separability inflexibility of most functional forms makes parametric tests of these restrictions appear problematic. We follow Pudney (1981) in stressing the usefulness of a description of the separable structure of preferences underlying an estimated model, and propose a non-iterative method for the production of such a description. An illustration with different models estimated for nine categories of goods on French aggregate time-series data is presented.

6 citations


Journal ArticleDOI
TL;DR: In this paper, the geometrical characteristics and spectroscopic properties of PF2H have been analyzed and the dissociation energy obtained is 66.5 kcal mol−1.
Abstract: Ab initio valence shell electron calculations of the geometrical characteristics and spectroscopic properties of PF2H have been performed. Several basis sets have been used to optimize the geometry and calculate vibrational frequencies of normal modes and force constants at the SCF level. The dissociation energy obtained is 66.5 kcal mol−1. The two first vertical ionization potentials are evaluated at 11.0 and 23.6 eV. Finally, the electronic spectrum of this molecule is discussed.

4 citations


Journal ArticleDOI
TL;DR: Phytoplankton evolution was established during a study carried out on lake Ichkeul (Tunisia) from January 1985 to June 1988, and the relations between phytopLankton composition and photosynthetic activity were discussed.
Abstract: Phytoplankton evolution was established during a study carried out on lake Ichkeul (Tunisia) from January 1985 to June 1988. During this period, the flora, composed of 51 species is distributed principally between Diatomophyceae and Chlorophyceae. Succesional changes of phytoplankton were often unpredictable and characterized by populations with monospecific trend. Photosynthetic activity and the parameters Aopt and IK were studied regularly along the year 1985 by oxygen method (GOLTERMANN, 1969). The relations between phytoplankton composition and photosynthetic activity were discussed.

4 citations


Journal ArticleDOI
TL;DR: Glycine entry in vesicles as a function of time, in presence or absence of sodium, indicated an overshoot which decreased when incubation time was prolonged, and glycine transport by the brush border of D. pictus intestine presents a saturable component depending on sodium and on transmembrane electrical potential.

1 citations


Journal ArticleDOI
TL;DR: In this paper, X-ray diffraction investigations, calorimetric and dielectric measurements show the occurence of a structural phase transition at Tc = 250 K from a quadratic high temperature form (P4/mmm, Z = 2) to a triclinic low temperature form, corresponding to a slight deformation of the unit cell when decreasing the temperature.
Abstract: C2H5NH3Hg(CN)2Cl belongs to the family of materials with one-dimension structural character. X-ray diffraction investigations, calorimetric and dielectric measurements show the occurence of a structural phase transition at Tc = 250 K from a quadratic high temperature form (P4/mmm, Z = 2) to a triclinic low temperature form (P1, Z = 2) and corresponding to a slight deformation of the unit cell when decreasing the temperature.