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A single slope solar still coupled with a separated heat storage system consisting of a double glazing solar collector provided with latent heat storage material(PCM) is investigated in this paper. This system is moulded for working autonomously and continuously throughout the day. A transient model is developed for assessing the performances of this device under summer climatic conditions of the Algerian Sahara. In this model, the fraction of molten PCM was assessed at each time step, which allowed inspecting the evolution of PCM material during all the time of computations. The results indicate that the additional heat storage system supplied heat to the still for 20 h continuously during the daytime. Accordingly, it is found that the increase rates of daily and nocturnal yields were respectively 63% and 635% (an increase of more than six times) compared to the conventional system. Furthermore, it is exhibited that the useful energy is strongly influenced by the increase of PCM mass, so this parameter must be lowered as possible. Also, it is shown that in the summer season; there is an optimum tilt angle of 15° Meanwhile, it is demonstrated that a great part of the irreversibility generated in the system is caused by the solar radiation and the PCM irreversibility represents only 7% of the total irreversibility. It is also revealed that the daily irreversibility decreases slightly with increasing the water mass and collector slope angle, but possesses an optimum at a PCM thickness of 6 cm.

A transient one-dimensional model was developed for studying the thermal performance of earth-to-air heat exchangers (EAHE) for summer cooling under the Algerian Sahara. The effect of extremities was also taken into account. The model validation against both theoretical and experimental data of other researchers showed a good agreement. In addition, a detailed sensitive study was carried out in order to investigate the influence of geometrical and dynamical parameters on the thermal performance of EAHE. Results showed that the air outlet temperature decreases with increasing of pipe length but it increases with increasing of pipe cross section and air velocity. However, the daily mean efficiency increases when the length of pipe increases but it decreases when the cross section area of pipe or air velocity increases. It is also observed that the coefficient of performance drops quickly with increasing of air velocity. Considering as reference the thermal performance of EAHE under steady state conditions, the investigation of Derating Factor reveals that the thermal performance of EAHE in transient conditions is more influenced by the variation of operating duration, pipe diameter and air velocity.

In this paper, a new design of passive cooling system which consists in an Earth-to-Air Heat Exchanger (EAHE) assisted by a wind tower is presented. This system is intended for the summer cooling in hot and arid regions of Algeria. A transient analytical model was developed in order to investigate the influence of design parameters on the performance of the EAHE. The model of the EAHE is validated against both theoretical and experimental data carried out by other authors. Since it is well-known that the performance of the EAHE systems is more influenced by the air flow velocity, another model was presented to predict the air velocity inside the buried pipe. Moreover, a burying depth of 2 m was adopted and the period under consideration is July where the ambient temperature exceeds 45 °C. This study was also extended to examine the behaviour of system during the whole year. In addition, a sensitivity survey was curried out to investigate the influence of tower and pipe dimensions on the air flow velocity and the performances of the EAHE. Results showed that the wind tower dimensions (height, cross section) have not an important impact compared to the pipe dimensions (length, diameter). It is found that a tower with a total height of 5.1 m and a cross section area of 0.57 m 2 can generate an air flow rate of 592.61 m 3 /h. Furthermore, it has been also observed that the daily cooling potential reached a maximum of 30.7 kW h corresponding to a pipe length of 70 m. The cooling effectiveness of the system is compared to that of traditional passive cooling system consisting in a wind tower with wet surfaces. The results indicated that the ambient air after passing through the wind tower coupled to the EAHE is colder than of that of the leaving the conventional cooling tower.

The variation of magnetic susceptibility and heat capacity with temperature for the bimetallic nickel Ni(II)–copper Cu(II) cyclo-tetrametaphosphates (CuNiP 4 O 12 ) has been examined. The complex has a structure of quasi-one-dimensional alternate spins chains of Ni(II) and Cu(II) that exhibits a three-dimensional magnetic ordering at approximately 13.5 K. The compound is characterized by a ferromagnetic intrachain constant J F =4.05 K, with a significant effect of single ion anisotropy D =9.70 K. The chains are weakly coupled antiferromagnetically with an interchain exchange constant of 2 z AF J AF =−1.125 K.

Resume Le recours a la laparoscopie comme moyen diagnostique chez l'enfant est une procedure simple, sure et precise qui represente une alternative mini-invasive a beaucoup d'autres explorations diagnostiques. Les indications de cette laparoscopie diagnostique sont actuellement tres nombreuses et ne cessent de s'accroitre. Nous rapportons dans ce travail une etude prospective de 68 enfants ayant beneficie d'une laparoscopie a but initial diagnostique, sur une periode de 4 ans: de 1998 a 2001. Les principales indications de cette laparoscopie ont ete: la biopsie peritoneale dans 19 cas, les kystes ovariens chez 12 filles, la biopsie hepatique chez 10 enfants, les ambiguites sexuelles dans six cas, les icteres cholestatiques chez six nourrisons, les douleurs abdominales recidivantes dans huit cas, les masses abdominales dans cinq cas et les hemorragies digestives dans deux cas. A travers cette serie seront analyses les avantages ainsi que les differents points d'interet de cette nouvelle methode diagnostique.

Resume Observations. – Deux nouveau-nes, un de sexe masculin et l’autre de sexe feminin, ont ete pris en charge pour un syndrome d’occlusion neonatale basse. Pour les deux enfants un lavement opaque aux hydrosolubles a permis de poser le diagnostic de syndrome de petit colon gauche et de les traiter avec succes. Conclusion. – Le syndrome de petit colon gauche est une cause extremement rare d’occlusion neonatale ou le lavement opaque aux hydrosolubles constitue le moyen diagnostique et therapeutique.

Resume L'arthrite septique est definie par une inflammation d'origine bacterienne de la synoviale articulaire, c'est une affection frequente chez le nourrisson et l'enfant. Les auteurs rapportent leur experience dans cette pathologie a travers une serie de 554 enfants colliges sur une periode de dix ans, a l'hopital d'Enfants de Rabat au Maroc. Il s'agit de 369 garcons et 185 filles, âges de sept jours a 15 ans avec une moyenne de six ans et demi ; une porte d'entree a ete retrouvee chez 107 d'entre eux. La localisation la plus frequente est le genou qui represente avec la hanche plus de 79 % des localisations. La douleur et l'impotence fonctionnelle ont ete les principaux signes revelateurs de la maladie. Un traitement antibiotique et une immobilisation du membre chez tous les malades ont conduit a une guerison complete chez 543 enfants, chez 66 une arthrotomie a ete indispensable. L'evolution vers l'arthrite chronique ou recidivante a ete observee dans 11 cas. L'arthrite septique chez l'enfant est une urgence diagnostique et therapeutique qui repond favorablement a un traitement bien conduit, tout retard peut entrainer des sequelles graves.

Hydatidosis is endemic in Morocco, where the liver is the most frequently involved. Conservative treatment of this entity is possible by laparoscopy. Ten patients with hepatic hydatid cyst...

Resume L'hydrocolpos est defini par la retention vaginale de secretions cervicales et vaginales. Les manifestations cliniques sont plus souvent observees chez le nouveau-ne et le nourrisson que chez le jeune enfant. L'imperforation hymenale est l'etiologie la plus frequente ; un diaphragme vaginal complet plus haut situe ou une atresie vaginale partielle sont des causes plus rares. L'hymenectomie est le traitement de l'hydrocolpos par imperforation hymenale. Pour des retentions vaginales revelatrices d'une malformation plus grave, le traitement est plus complexe. Les auteurs rapportent une serie de quatre hydrocolpos dont trois ont ete reveles en periode neonatale et un chez un nourrisson de deux mois. Le diagnostic suspecte par la clinique a ete confirme par l'echographie. Le traitement a consiste en une hymenectomie en X chez les trois patientes qui avaient une imperforation hymenale. Chez la quatrieme qui avait une atresie vaginale, un drainage d'un pyocolpos a ete fait par cœlioscopie. L'evolution a ete favorable, excepte pour la patiente avec le pyocolpos qui est decedee dans un tableau de septicemie.

Introduction Les fentes oro-faciales sont des malformations congenitales frequentes, pouvant revetir differentes formes cliniques. Nous rapportons un cas exceptionnel de fente glosso-labio-mandibulaire. Observation Notre patient etait un nouveau-ne admis a la naissance pour syndrome malformatif facial responsable de trouble de la deglutition. Il s’agissait d’une forme particuliere de fente n o 30 selon la classification de Tessier, qui associait une langue bifide avec deux hemi-levres inferieures et deux hemi-mandibules. La prise en charge chirurgicale a ete precoce en raison des troubles alimentaires associes. Les suites operatoires ont ete simples, et les resultats esthetique et fonctionnel, avec un recul de 18 mois, etaient tres bons. Discussion Nous faisons une revue de la litterature de cette pathologie en rappelant son origine embryologique, ses differentes formes cliniques et sa prise en charge medico-chirurgicale.

Resume La tuberculose urogenitale est rare chez l'enfant. Observations. Cas I . Un garcon âge de 10 ans a consulte pour une cystite trainante ; l'ECBU montre une pyurie sans germes avec absence de bacille de Koch a l'examen direct et a la culture. L'UIV a mis en evidence une ureterohydronephrose gauche avec rein droit muet lequel, a l'echographie, etait le siege d'une nephrite « xanthogranulomateuse . L'histologie de la piece operatoire de la nephrectomie droite a identifie des follicules epithelio-gigantocellulaires. Malgre le traitement, l'evolution est emaillee de complications vesicales. Cas 2. Un garcon âge de 9 ans a ete admis pour suspicion d'appendicite. L'echographie renale montrait un aspect d'abces renal droit dont l'exploration chirurgicale evoquait une origine tuberculeuse confirmee par l'histologie. Le bacille de Koch a ete identifie dans les urines. Sous traitement medical, l'evolution a ete favorable. Conclusions. La tuberculose urogenitale pose des difficultes diagnostiques et therapeutiques. Malgre l'apport des antibacillaires, le pronostic est fonciton de la precocite du diagnosite.

Rectal atresia is a rare condition, with a reported incidence of 1-2% of all anorectal anomalies. The extensive list of ingenious operative procedures used for the correction of this malformation is testimony to the great difficulty faced in treating this anomaly. Posterior sagittal anorectoplasty using end-to-end anastomosis is a safe, technically well known that achieves this goal.

The magnetic properties of the one dimensional Cu(II)(1,4-C 4 H 4 N 2 )(C 4 O 4 )(H 2 O) 4 have been studied. This compound is a typical linear chain. Susceptibility measurements show strong antiferromagnetic intrachain exchange of the order of −8.72 K with poor interchain exchange coupling.

Resume Les testicules impalpables representent environ 10 a 20 % de l’ensemble des testicules non descendus. La place de la laparoscopie est de plus en plus importante, car a son role diagnostique s’est ajoute recemment un interet therapeutique. Trente-cinq testicules non palpables ont beneficie d’une exploration laparoscopique aux urgences chirurgicales pediatriques de l’hopital d’enfants de Rabat au cours de ces 2 dernieres annees. Dans 9 cas, il s’agit d’une agenesie testiculaire. Dans 6 cas, le testicule a ete haut situe et un premier temps laparoscopique d’abaissement a ete realise. Dans 10 cas, un abaissement en un seul temps a ete effectue. Dans 10 cas, la laparoscopie a montre le canal deferent et les vaisseaux spermatiques qui convergent vers le canal inguinal, une exploration inguinale a ete alors effectuee. La duree d’hospitalisation a ete de 24 heures, on n’a pas note de complications. Nous presentons ce travail pour sensibiliser les chirurgiens sur la nouvelle approche therapeutique afin d’optimiser la prise en charge des enfants cryptorchides.

Background: Cryptorchidism results from anomalies of migration of the testis and is common in children. This pathology often poses a therapeutic dilemma, especially if the testis is intra-abdominal...

In 2004, a combined system test was performed in the H8 beam line at the CERN SPS with a setup reproducing the geometry of sectors of the ATLAS Muon Spectrometer, formed by three stations of Monitored Drift Tubes (MDT). The full ATLAS analysis chain was used to obtain the results presented in this paper. The basic design performances of the Muon Spectrometer were verified. The stability of MDT calibration constants, the alignment system using optical devices and high energy tracks, as well as the intrinsic sagitta resolution of the Muon Spectrometer were studied and found to agree with expectations. The reconstruction of muon tracks using the combined information from both the Inner Detector and the Muon Spectrometer are also presented. © 2008 Elsevier B.V.

Background/Purpose: Five children with pancreatic pseudocyst were treated from 1986 to 1998, 4 of these pseudocysts have a traumatic origin. Medical therapy reduces the pancreatic stimulation and favors the resolution or the maturation of the pseudocyst. Methods: First, all the children were treated with ultrasound-guided drainage. The duration of this drainage varied from 1 to 10 days with successful results in 3 cases. The internal drainage by cystogastrostomy was used in 2 cases. Results: The first showed a cystogastric fistula in the fifth day of the external drainage, the second was drained 2 times without success. There were no pseudocyst recurrences, and children treated surgically were discharged home within 7 to 10 days after operation.

Infantile myofibromatosis is a rare fibrovascular-like tumour, characterized by the development of single or multiple nodular lesions arising from cutaneous, subcutaneous, muscular bone or visceral structures, diagnosed before 2 years.We report a case of infantile myofibromatosis located on the jaw, which is unique because of its large size (12 cm), its location and its neonatal presentation. It was a voluminous proliferate tumour with an ulcerated centre, located on the left jaw. Surgical excision was complete and the diagnosis was maded on histological examination. Recovery was uncomplicated with no recurrence on follow up.Diagnosis of infantile myofibromatosis is difficult because of the clinical heterogeneity and the histopathological appearance. The histological diagnosis relies on identification of two separate components, fascicular myofibroblastic at the periphery and hemangiopericytome in the centre. The most freqaent treatment is conservative surgical excision, because recurrence rates are low and there is a possibility of spontaneous regression. Some authors recommend conservative management of very large or multiple lesions particularly if excision will result in significant functional or cosmetic morbidity.

The oro-facial clefts are very frequent congenital malformations, with many clinical forms. We report an exceptional case of median cleft of the tongue, the lower lip and the mandible.Our patient was a new born, admitted in our unit for major facial malformation with swallowing disorder. The patient presented a particular form of cleft no 30 in Tessier's classification, which associated two hemi-tongues, two hemi-lower lips and two hemi-mandibles. Surgery was performed early because of the swallowing disorder. Cosmetic and functional results were positive, with 18 month follow-up.With a review of the literature, we describe this pathology, its embryologic origin, its different clinical forms and its treatment.

The impalpable testicles account for approximately 10 to 20% of the total of the not descended testicles. The importance of laparoscopy is increasingly significant, because apart from its diagnostic role recently a therapeutic interest was added. Thirty-five nonpalpable testicles took advantage of laparoscopic exploration at the pediatric's emergency surgery ward at the children's hospital of Rabat within the last 2 years. In 9 cases, total testicular agenesis was found. In 6 cases the testicles were situated very high in the abdomen, so that a first time laparoscopy was performed where the testicles were lowered. In 10 cases, one laparoscopic intervention for lowering the testicles was sufficient. In 10 cases, laparoscopic surgery showed that the vas deferens and the spermatic vessels reunified in the inguinal; so that, Inguinal exploration was necessary. The time of hospitalisation was 24 h with no complications noticed. We present this work to sensitise the surgeons on the new therapeutic approach to optimise the taking care of cryptorchid boys.

Two newborns, one female and male were treated for neonatal bowel obstruction. A contrast enema led to the diagnosis of small left colon syndrome and treated those newborns successfully.Small left colon syndrome is a very rare cause of neonatal bowel obstruction. The diagnosis and treatment are assured by a simple contrast enema.

Tuberculosis of the uro-genital tract is uncommon in both sexes before puberty.Case 1. A 10 year-old boy suffered from chronic cystitis. Urine examination showed pyuria without bacteria and absence of mycobacterium tuberculosis on direct smears and culture. Intravenous pyelography showed left ureterohydronephrosis and a non functioning right kidney with calcifications. A right nephrectomy was performed which showed caseous lesions with granulomas. A triple specific therapy failed to completely cure the vesicoureteral lesions. Case 2. A 9 year-old boy was admitted for the suspicion of appendicitis. Renal ultrasonography showed features of abscesses located to the right kidney and the liver. Laparotomy showed their tuberculous origin which was confirmed by histological examination and positive search for Mycobacterium tuberculosis in urine. The course was favorable under specific treatment.Diagnosis of tuberculosis of the uro-genital tract may be difficult leading to a delayed treatment and sequellae.

Introduction La veine porte preduodenele (VPPD) est une ectopie de la veine porte qui au lieu de se situe en arriere de la grande cavite des epiploons, elle prend une situation en avant du pancreas et du duodenum.La presente etude a pour objectif d’offrir l’information sur les malformations associees a la VPPD et sur son ethiopathogenie. Objectifs par la synthese des donnees issues des differents articles, nous avons essaye: 1 - D’analyser les frequences des associations malformatives a la VPPD 2 - De formuler les hypotheses sur l’etiopathogenie de la VPPD 3 - D’etudier les implications pratiques de la VPPD Methodes C’est par la recherche dans les bases de donnees et l’extraction des references des articles publies. Tous les articles ayant decrit individuellement les cas de la VPPD chez les enfants dont l’âge est moins de 2 ans ont ete retenus. Nous avons analyse les frequences des associations malformatives a la VPPD. Resutats Analyse documentaires a permis de cerner 77 articles et de retenir 31 articles dont 28 sont des cas et 3 sont des etudes retrospectives. Un totale de 66cas a ete etudie, 34 n.nes et 32 nourrissons. Conclusion L’analyse statistique a permis de distinguer au sein des malformations associees a la VPPD plusieurs groupes. Cette association serait en faveur de son heterogeneite etiopathogenique