342 research outputs found
Study of the propolis extract as a corrosion inhibitor of copper alloy in ethylene glycol/water 0.1 M NaCl
The effect of propolis extract as a corrosion inhibitor of copper alloy in ethylene glycol / water 0.1 M NaCl solution was studied by electrochemical measurements. The Tafel polarization curves showed that the propolis extract at different concentration acts as mixed inhibitor, and the maximum value of the inhibitory efficacy is 73.28% at optimum concentration of 1.25 g/L of propolis extract. The activation parameters reveal that the inhibitor molecules on copper surface are absorbed by physisorption and obey Langmuir isotherm adsorption. These results were supplemented by IR Spectroscopy, Scanning electron microscopy (SEM) and EDX spectrum of chemical composition. The metal solution interface is simulated as a physical model by using Electrochemical Impedance Spectroscopy (EIS).Keywords: Copper Alloy, Propolis extract, ethylene glycol; Corrosion inhibition; Adsorption, Electrochemical impedance Spectroscopy (EIS
A giant occipital encephalocele: A case report
Occipital encephalocele is a rare congenital anomaly that is characterized by herniation of brain tissue through a defect in the skull. Because of their enormous size, they pose a surgical challenge. Occipital encephalocele is the commonest of all encephalocele; the management of encephalocele defects requires immediate surgical closure. The author reports a case of a five months old female baby who presented a progressively increasing swelling over the occipital region. This swelling was present since birth. Surgery was planned to reduce the size of the swelling as well as its contents. The sac was excised and reduced sufficiently enough to accommodate the healthy-looking brain tissue. This infant did well postoperatively
Treatment of chronic pain by spinal cord stimulation
Failed back surgery syndrome (FBSS) is often used to describe the condition of patients who have experienced continued pain after surgery. It is of multifactorial genesis and may be the consequence of various lumbar spinal diseases; lumbar disc herniation surgery or spinal canal stenosis laminectomy. The presented series included 13 patients affected with chronic pain related to FBSS who underwent implantation of spinal cord stimulation. The mean percentage of pain relief was 90 % for all patients. 60% of the patients were in a better psychological status and the intake of analgesic medications has been reduced of more than 70%. More than 50% of the patients could resume professional activities. Analysis of the risks and benefits comes in favour of spinal cord stimulation
Resection of giant invasive thoracic schwannoma: Case report
Even though spinal nerve sheath tumours, presented especially by schwannomas, are considered to be mostly benign; they can gain a huge size and have an invasive behaviour, causing spinal cord compression, bone destruction, and make the total removal of the tumour a real challenge for the surgeon. This type of tumours is recently described as giant invasive spinal schwannoma (GISS), this type rarely reported in the thoracic region; deserve a special studying vis-a-vis the diagnosis and the management of both the tumour and the bone destruction.  
Early diagnosis and management of traumatic dura tear with brachial plexus injury without spinal lesions in childhood
Although the dura is a thick membrane, it could be severed in spine surgery and less frequently by a traumatism (7,8,10); in this case, it is usually accompanied with bone or ligamentous injury (2). Rare cases are reported of a traumatic dura tear without spinal lesion and would suspect in the first place a brachial plexus injury (2,8). Dura tears are rarely seen in childhood (3). We report a case of early diagnosis of dura tear in brachial plexus injury without bone or ligamentous lesions on a child of 4 years old and we discuss the diagnostic and treatment modalities
Communicating spinal epidural thoracic arachnoid cyst en-bloc resection: A case report
Background: Spinal extradural arachnoid cyst is an uncommon, expanding lesion which may communicate with the subarachnoid space, The etiology still remains unclear, but the most accepted explanation is the existence of areas of weakness in the spinal dura , Spinal arachnoid cysts are usually in the thoracic spine, and they may cause symptoms due to spinal cord compression.
Case Presentation: Patient is a 54-years-old female who presented with progressive back pain and motor deficit, Magnetic resonance imaging (MRI) study revealed an extradural cyst extending from T2 to T4 isointense with the cerebrospinal fluid (CSF) on all sequences and did not enhance on T1-weighted post-contrast MRI. Patient underwent T2-T4 laminectomy, en-bloc resection of the lesion was achieved and the histopathological examination objectified an arachnoid cyst.
Conclusion: Spinal extradural arachnoid cyst can cause neurologic deficit and the mainstay of treatment in patients with neurological symptoms is surgical removal of the cyst together with ligation of the communicating pedicle and closure of the dural defect
Thermal Performance of Hybrid PVT Collector with Natural Circulation
Hybrid photovoltaic thermal (PVT) collectors allow simultaneous production of electrical energy thus heat energy. There are several configurations of hybrid collectors (to produce water or air). For hybrids water collectors, there are several configurations that differ by the nature of the absorber (serpentine, tubes...). In this paper, an absorber tank is studied. The circulation of the coolant is natural (we do not use the pump). We present the obtained results in our experimental study and we analyzed the data, and then we compare the results with the theory practices. The electrical performances of the hybrid collector are compared with those of conventional photovoltaic module mounted on the same structure and measured under the same conditions. We conducted experiments with natural circulation of the coolant (Thermosyphon), for a flow rate of 0.025kg/m²
Otospongiose : a propos de 149 cas
Introduction : L’otospongiose est une ostéodystrophie de la capsule otique se traduisant par une surdité de transmission ou plus rarement une surdité mixte d’apparition progressive. Le but de notre travail est d’analyser les caractéristiques épidémiologiques, cliniques, paracliniques et comparer les résultats en fonction de l’âge, du stade de l’ostéodystrophie, de la technique chirurgicale et de la prothèse.Patients et méthodes : notre étude est rétrospective portant sur 124 patients (149 oreilles) colligés sur une période de 9 ans (2000-2008).Résultats : notre population a comporté 86 femmes et 38 hommes. La moyenne d’âge à l’intervention était de 39,82 ans. La surdité était bilatérale dans 61,3% des cas et unilatérale dans 38,3%. Les seuils moyens préopératoires de la conduction osseuse et aérienne étaient respectivement de 17,33 dB et 52,52 dB, le rinne moyen était de 35,19 dB. La tomodensitométrie a été réalisée chez 63 patients. On a réalisé 21 platinectomie totale, 24 platinectomie partielle et 101 platinotomie calibrée. Selon la classification de Portmann, on a trouvé une répartition sensiblement égale entre les stades II, III et IV. On a utilisé un piston téflon 6/10 mm dans 119 cas et 4/10 mm dans 27 cas. Le rinne moyen postopératoire était de 15,95 dB. a 1 an, le rinne était de 14,81 dB avec un résultat satisfaisant de 94,2%.Conclusion : Il ressort de notre travail que certains facteurs semblent prédictifs de bons résultats et qui sont : le sexe féminin, l’âge <50 ans, le stade chirurgical< stade IV, la platinotomie, et le piston 0,4 mm.Mots clés : otospongiose, conduction osseuse, conduction aérienne, platinotomie, platinectomie.Objective : Otosclerosis is a common disorder of the otic capsule characterized by the presence of a progressive conductive or rarely mixed hearing loss. The aims of this study were to analyses the epidemiologic, clinical, paraclinical characteristic and compare our results according to age, stage, surgical technique and prosthesis. Patients et méthodes : Our study is retrospective about 124 patients (149 ears) in the period of 9 years (2000-2008).Results: Our population included 86 female and 38 male patients. mean age at intervention time was 39,82 years. The hearing loss was bilateral in 61,3% of cases and unilateral in 38,3%. The bone and air conduction threshold was 17.33 dB and 52,52 dB, the air-bone gap was 35,19 dB. The CT scan was realized in 63 patients. We have realized 21stapedectomy, 24 partial stapedectomy and 101 stapedotomy. In accordance with Portmann classification, the distribution between II, III and IV stages was almost equal. We used 6/10 mm Teflon piston prosthesis in 119 cases and 4/10 mm in 27 cases. The postoperative air-bone gap was 15,95 dB. after 1 year, the air-bone gap was 14,81 dB with a satisfying results in 94,2%.Conclusion: it seems that some factors are predictive for good results like a female sex, age<50 years, stage< stage IV, platinotomy and piston 4/10 mm.Keyswords : otosclerosis, bone conduction, air conduction, stapedectomy, stapedotom
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