Modelling soil erosion in a Mediterranean watershed: Comparison between SWAT and AnnAGNPS models.

In this study, the simulations generated by two of the most widely used hydrological basin-scale models, the Annualized Agricultural Non-Point Source (AnnAGNPS) and the Soil and Water Assessment Tool (SWAT), were compared in a Mediterranean watershed, the Carapelle (Apulia, Southern Italy). Input data requirements, time and efforts needed for input preparation, strength and weakness points of each model, ease of use and limitations were evaluated in order to give information to users. Models were calibrated and validated at monthly time scale for hydrology and sediment load using a four year period of observations (streamflow and suspended sediment concentrations). In the driest year, the specific sediment load measured at the outlet was 0.89 t ha-1 yr-1, while the simulated values were 0.83 t ha-1 yr-1 and 1.99 t ha-1 yr-1 for SWAT and AnnAGNPS, respectively. In the wettest year, the specific measured sediment load was 7.45 t ha-1 yr-1, and the simulated values were 8.27 t ha-1 yr-1 and 6.23 t ha-1 yr-1 for SWAT and AnnAGNPS, respectively. Both models showed from fair to a very good correlation between observed and simulated streamflow and satisfactory for sediment load. Results showed that most of the basin is under moderate (1.4-10 t ha-1 yr-1) and high-risk erosion (> 10 t ha-1 yr-1). The sediment yield predicted by the SWAT and AnnAGNPS models were compared with estimates of soil erosion simulated by models for Europe (PESERA and RUSLE2015). The average gross erosion estimated by the RUSLE2015 model (12.5 t ha-1 yr-1) resulted comparable with the average specific sediment yield estimated by SWAT (8.8 t ha-1 yr-1) and AnnAGNPS (5.6 t ha-1 yr-1), while it was found that the average soil erosion estimated by PESERA is lower than the other estimates (1.2 t ha-1 yr-1).

[Indications of the expansion in pediatric surgery. Experience of 30years and literature review]. / Indications de l'expansion chez l'enfant. Expérience de 30ans d'activité et revue de la littérature.

The expansion of soft tissue, especially skin, is an old and physiological process to increase the skin reserve allowing excision while coveraging of the resulting loss of substance. Easy in principle, this process is subjected to constraints in children requiring precise planning and rigorous technical procedure. Between 1990 and 2016, we performed 293 expansion protocols with 411 implants in 244 children. The scalp was the most interested area (158 cases), followed by the trunk (29). The congenital nevi represented the most frequent indication (119 cases), followed by sequelae of burns and scars (64 cases) and hamartoma sebaceous of Jadassohn (27 cases). Three categories of indication can be established. Ideal indications of the expansion are on the scalp, skin preparation prior to the excision of a large nevus, nevus sebaceous of Jadhasson and severe breast hypoplasia. Common but delicate indications are scars, especially after burns, treatment of vertex aplasia cutis congenita and expansions of the limbs, abdomen, head and neck. Rare indications include separation of Siamese twins, or protection of the bowel before radiotherapy. Contra-indications are infected lesions, malignant tumors and lesions requiring immediate coverage. If the principle of expansion is relatively simple, its positioning on the scale of reconstruction methods is harder because of the risk of significant complications.

Removal of copper powder from aqueous solution by cementation using an agitated vessel.

The present study is concerned with the removal of copper powder from aqueous solution by cementation on a stationary disc placed inside an agitated vessel. The influence of several parameters on the rate of cementation, such as initial copper sulphate concentration, impeller rotational speed, presence of surfactant (Triton X-100), distance between the disc and the impeller, type of blade turbine and presence of baffles, has been investigated. The rate of cementation was found to increase with increasing impeller rotational speed and initial copper sulphate concentration. On the other hand, the rate decreases with increasing distance between the disc and the impeller. The rate of cementation was inhibited in solutions containing Triton X-100. Performance of a four-blade 90 degree turbine with regard to the rate of copper cementation was superior to the performance of a four-blade 45 degree pitched turbine. The present data can be correlated in terms of mass transfer coefficient of cementation as Sh = 0.905 Sc0.33 Re0.89 (d/l)0.41 (four-blade 90 degree turbine); Sh = 0.815 Sc0.33Re0.79 (d/l)0.47 (four-blade 45 degree pitched turbine), for the conditions 2035 < Sc < 2810 and 35,000 < Re < 179,000.

Outcome of cholelithiasis in Sudanese children with Sickle Cell Anaemia (SCA) after 13 years follow-up.

BACKGROUND: SCA causes chronic haemolysis which is a risk factor for cholelithiasis. OBJECTIVE: To determine the prevalence and outcome of children with SCA complicated with gallstones treated at the sickle cell clinic at the children emergency hospital Khartoum state. METHODS: 261 patients age 4 months to 16 years were studied. AUS examination was carried out. The 30 patients in whom gall stones were detected followed prospectively from June 1996 to September 2009 when a second AUS examination was obtained. RESULTS: Gall stones occurred in 30 patients of whom four were lost to follow up in the first year. The overall prevalence of cholelithiasis was 11.5% and it increased with age. The youngest patient with cholelithiasis was 2 1/2 years old. Haematological variables, bilirubin and sex did not identify a subgroup of patients at higher risk for gallstones. All the patients were asymptomatic at the time of diagnosis. One patient developed symptoms 3years after the diagnosis and he was submitted to surgery. The 25 remaining asymptomatic patients were followed up for 13 years and none of them presented complications related to cholelithiasis during this period. CONCLUSION: The prevalence of cholelithiasis in Sudanese children and adolescents with SCA was significant. The large majority patients remained asymptomatic over a long period.

Surgical and prosthetic treatment for microphthalmia syndromes.

Our aim was to evaluate the long-term outcomes of prosthetic treatment and orbital expansion in the management of microphthalmia syndromes. We did a retrospective single-centre study of all cases of microphthalmia treated between 1989 and 2010. The patients were divided into three groups: isolated microphthalmia, microphthalmia associated with micro-orbitism, and complex microphthalmia syndrome. To evaluate the results a score was computed for each patient by assessing the length of the palpebral fissure, the depth of the conjunctival fornix, and local complications together with an evaluation of the satisfaction of patients and their families. Forty-four children were included (27 boys and 17 girls). Twenty-seven had unilateral microphthalmia (61%) and 17 bilateral microphthalmia (39%). Twelve patients were lost to follow up. The mean duration of follow-up was 12 years (range 4-21). Management involved an ocular conformer in only 31 patients (71%). The treatment was deemed satisfactory in all except 10 children. Surgical treatment with orbital expansion permitted good symmetry of the orbital cavities with a final mean difference of 9% (range 3-17) compared with the initial 16.8% (range 13.6-20.3). The prosthetic treatment gives satisfactory results. Despite limited indications and difficult follow-up, our experience emphasises the value of surgical treatment for severe micro-orbitism.

Electrochemical removal of phenol from oil refinery wastewater.

This study explores the possibility of using electrocoagulation to remove phenol from oil refinery waste effluent using a cell with horizontally oriented aluminum cathode and a horizontal aluminum screen anode. The removal of phenol was investigated in terms of various parameters namely: pH, operating time, current density, initial phenol concentration and addition of NaCl. Removal of phenol during electrocoagulation was due to combined effect of sweep coagulation and adsorption. The results showed that, at high current density and solution pH 7, remarkable removal of 97% of phenol after 2h can be achieved. The rate of electrocoagulation was observed to increase as the phenol concentration decreases; the maximum removal rate was attained at 30 mg L(-1) phenol concentration. For a given current density using an array of closely packed Al screens as anode was found to be more effective than single screen anode, the percentage phenol removal was found to increase with increasing the number of screens per array. After 2h of electrocoagulation, 94.5% of initial phenol concentration was removed from the petroleum refinery wastewater. Energy consumption and aluminum Electrode consumption were calculated per gram of phenol removed. The present study shows that, electrocoagulation of phenol using aluminum electrodes is a promising process.

Chlamydial etiology of acute lower respiratory tract infections in children in the Sudan.

The role of Chlamydia pneumoniae in 110 Sudanese children with signs of acute lower respiratory tract infections (ALRI) was investigated. Four (3.6%) had evidence of C. pneumoniae infection, of whom 3 were culture-positive, while 1 had an antibody response suggesting a recent infection. IgG antibodies at a titer of > or = 1:32 to C. pneumoniae, Chlamydia psittaci and Chlamydia trachomatis were detected in 27 (24.5%), 27 (24.5%) and 7 (6.4%) of the 110 ALRI cases, respectively. C. pneumoniae, C. trachomatis or C. psittaci were not detected in nasopharyngeal secretions from any of 110 patients when fluorescence-labeled specific monoclonal antibodies were used. In a seroepidemiological survey, 318 healthy Sudanese persons aged between 1 month and 67 years were studied for C. pneumoniae antibodies.