53 research outputs found
SUCCESSFUL TWIN PREGNANCY IN A WOMAN WITH A UNICORNUATE UTERUS
No full textOumaima Sarhdaoui*, Andovalona Rabarijaona, Manar Rhemimet, Aziz Slaoui, Najia Zraidi, Amina Lakhdar, Abdelaziz Baidada and Aicha Kharbac
A CASE OF CYSTIC DEGENERATION OF A GIANT UTERINE LEIOMYOMA MIMICKING AN OVARIAN MALIGNANCY
No full textOumaima Sarhdaoui*, Meryem Benayada, Mouna Anibri, Aziz Slaoui, Najia Zraidi, Amina Lakhdar, Abdelaziz Baidada and Aicha Kharbac
Rapid Thermal Dopants Diffusion and Surface Passivation for Silicon Solar Cells Applications
No full textAbstractLimiting thermal exposure time using Rapid Thermal Processing (RTP) is now emerging as a promising simplified process for manufacturing of terrestrial solar cells in a continuous way. In this work, we present results on simultaneous formation of emitter, back-surface field and surface passivation in a single rapid thermal cycle. Spin-on dopants (SOD) solutions are used as dopant sources. Optimal emitter profiles, low sheet resistances and high gettering effect are reached. The residual SOD film is used as a surface passivation layer. Solar cells with efficiencies in the range 10 – 14 % are obtained depending on temperature and time processing.</jats:p
The New Copper Composite of Pastes for Si Solar Cells Front Electrode Application
No full textAbstractIn this paper we present a new composite (CuXX) of pastes for formation electrodes in crystalline silicon solar cells. The CuXX composite is obtained by chemical processing of copper particles and added to commercially available paste used for front electrode deposition on Si solar cell. The CuXX offers a possibility to exchange over 50wt. % Ag into Cu, which significantly decreases the material cost and therefore overall solar cell price. Solar cells with 50% wt. share of Cu as front electrode pastes were fabricated. The cells were characterized by current-voltage and spectral response techniques. Despite the non-optimized fabrication process, Cz-Si based solar cells with an efficiency approaching 14% were obtained
Malignant Degeneration of a Mature Ovarian Teratoma
No full textMature cystic teratoma is the most common type of ovarian germ cell neoplasm, but occasionally, it can undergo malignant transformations, especially in postmenopausal women. These secondary malignant neoplasms are most commonly squamous cell carcinomas. The absence of clinical and radiological specificity of this transformation means that the diagnosis remains purely histological. Data is insufficient regarding the appropriate management given their rarity. However, the treatment is multidisciplinary and is based on surgery and a platinum-based chemotherapy regimen. We report the case of a 53-year-old postmenopausal female patient with malignant transformation of the ovarian teratoma who was treated surgically and whose outcome was favorable. The diagnosis of the teratoma was evoked on imaging, while the diagnosis of squamous cell carcinoma was revealed on histology. Malignant transformation is an uncommon complication of mature ovarian teratomas. No clinical, radiological, or biological sign is specific; therefore, resection of any ovarian mass, even asymptomatic, is required
Cesarean scar pregnancy: A clinical case report
No full textBackground: Among the different forms of ectopic pregnancy, cesarean scar pregnancy is one of the most uncommon with an estimated incidence of 1/1800 pregnancies. A major risk of massive hemorrhage, it requires active management as soon as it is diagnosed because it can affect the functional prognosis of the patient (hysterectomy) but can also be life-threatening. Different surgical techniques are generally proposed in first intention to patients who no longer wish to have children, who are hemodynamically unstable and/or in case of failure of medical treatment.Case presentation: We hereby report the case of a young 19-year-old patient with no particular medical history, gravida 2 para 1 with a live child born after a cesarean section for fetal heart rhythm abnormalities during labor 5 months earlier and who presented to the emergency room of our structure for the management of a cesarean pregnancy scar diagnosed at 6 weeks of amenorrhea. She was successfully managed with an intramuscular injection of methotrexate. The follow-up was uneventful.Conclusion: The implantation of a pregnancy on a cesarean section scar is becoming more and more frequent. With consequences that can be dramatic, ranging from hysterectomy to life-threatening hemorrhage, clinicians must be familiar with this pathological entity and be prepared for its management. The latter must be rapid and allow, if necessary, the preservation of the patient's fertility. In this sense, conservative medical treatment with methotrexate injections should be proposed as a first-line treatment in the absence of contraindication
Meigs syndrome: About an uncommon case report
No full textBackground: Ovarian fibroma is a very unusual epithelial tumor representing less than 1% of all ovarian tumors. It can be asymptomatic and discovered during surgery or be associated with a pleural effusion preferentially located on the right side and a more or less abundant free ascites in the framework of the so-called Meigs syndrome. The challenge of management then lies in distinguishing benign from malignant since clinically, radiologically, and biologically everything points towards malignant which requires radical surgical treatment. We report here the case of a 69-year-old postmenopausal patient with a clinical form of Meigs' syndrome that strongly suggested ovarian cancer.Case presentation: We hereby report here the case of a 69-year-old patient, menopausal, gravida 4 para 3 with 3 live children delivered vaginally and one miscarriage. She presented with ascites, hydrothorax, and a solid tumor of the ovary. Serum CA 125 and HE 4 levels were very high. ROMA score was highly suggestive of malignancy. A hysterectomy with adnexectomy was performed. It was only the histological evidence of ovarian fibroma and the rapid resolution of its effusions that confirmed Meigs syndrome.Conclusion: Meigs syndrome is an anatomical-clinical entity that associates a benign tumor of the ovary, ascites, and hydrothorax. Highly elevated CA 125 and HE-4 tumor markers often point clinicians toward a malignant tumor and compel radical surgical treatment. This case report reminds us once again that only histology confirms the diagnosis of cancer
Une revue systématique sur le style de leadership transformationnel et les comportements de performance organisationnelle
No full textResearch into corporate governance has produced a varied and inconclusive set of findings regarding the relationship between managerial practices and organizational performance. Faced with this observation, the main aim of this article is to carry out a systematic review of transformational leadership as implemented by managers within companies. To achieve this objective, the author followed the methodology of the PRISMA (Preferred Reporting Items For Systematic Reviews and Meta-Analyses) research protocol to review and analyze a total of fifty-one articles that met the inclusion and relevance criteria established for this study. The results of this systematic review reveal that, although previous studies may have come to sometimes contradictory conclusions, a large majority of researchers found a significant relationship between transformational leadership and various aspects of organizational performance. More specifically, transformational leadership is closely linked to elements such as performance, employee mobilization, workplace climate, and commitment to work in a growing economic context. It is clear from this systematic review that, in some contexts, a definitive consensus has yet to be reached. The findings of this study provide an overview of the available evidence, while identifying avenues for future research.
Keywords: leadership styles, transformational leadership, organizational performance, organizational behaviors.
JEL Classification: M10, M21, M54, O15, L20.
Paper type: Theoretical researchLa recherche sur la gouvernance d’entreprise a engendré un ensemble de conclusions variées et peu concluantes en ce qui concerne la relation entre les pratiques managériales et la performance organisationnelle. Face à ce constat, l’objectif principal de cet article est de réaliser une revue systématique du leadership transformationnel tel qu’il est mis en œuvre par les cadres au sein des entreprises. Pour atteindre cet objectif, l’auteur a suivi la méthodologie du protocole de recherche PRISMA (Preferred Reporting Items For Systematic Reviews and Meta-Analyses) pour examiner et analyser un total de cinquante-et-un articles qui répondaient aux critères d’inclusion et de pertinence établie pour cette étude. Les résultats de cette revue systématique révèlent que, bien que les études précédentes aient pu aboutir à des conclusions parfois contradictoires, une grande majorité des chercheurs ont mis en évidence une relation significative entre le leadership transformationnel et divers aspects de la performance organisationnelle. Plus précisément, le leadership transformationnel est étroitement lié à des éléments tels que le rendement, la mobilisation des employés, le climat au travail, et l’engagement au travail dans un contexte économique en plein essor. Il apparait clairement à travers cette revue systématique que, dans certain contexte, un consensus définitif n’a pas encore été atteint. Les conclusions de cette étude fournissent un aperçu des preuves disponibles tout en identifiant les pistes de recherche futures.
Mots-clés : styles de leadership, leadership transformationnel, performance organisationnelle, les comportements organisationnels.
Classification JEL : M10, M21, M54, O15, L20.
Type de l’article : Article théorique
 
Yb-doped zinc tin oxide thin film and its application to Cu(InGa)Se2 solar cells
No full textInternational audienceThe use of rare earth elements with semiconductor materials has attracted immense interest due to their unique properties. In this study, we investigated the characteristics of an ytterbium (Yb)-doped zinc tin oxide (Yb:ZTO) thin film and its application as a potential down-converter of Cu(InGa)Se 2 (CIGS) thin-film solar cells. Yb:ZTO thin films were deposited by reactive sputtering of Zn and Sn metal with oxygen flow. A few pieces of Yb were embedded in a Zn metal target; thus Yb elements were supplied during Zn sputtering. The relative composition of Zn and Sn was controlled by changing the sputtering power (10-70 W) of Sn, in relation to the fixed sputtering power for Zn (70 W). In addition, the substrate temperature was varied from room temperature to 400°C. It was confirmed that a smaller amount of Sn with lower sputtering power led to more incorporation of Yb into ZTO. X-ray photoelectron spectroscopy analysis confirmed the incorporation of Yb into ZTO, and photoluminescence measurement demonstrated Yb emission. Grazing incidence X-ray diffraction indicated the shift of ZTO emission peaks induced by the difference in the composition of Zn and Sn. Finally, CIGS solar cells with an Yb:ZTO layer were fabricated. The results suggested that cells with the highest Yb photoluminescence emission showed the highest short-circuit current density and cell efficiency
Sensitive Bandgap Reduction of SrTiO3 through Incorporation of Sulfur Using Ion Implantation
No full textSrTiO3 (STO) is a well-known perovskite oxide often used, among others, as a crystalline substrate for epitaxial deposition. However, its indirect bandgap of 3.25 eV is too high for solar applications. Tentative experiments to reduce its bandgap are very welcome. To this end, sulfurization of STO substrates using ion implantation is performed. The simulated profile is controlled by time-of-flight secondary-ion mass spectrometry. S is at least partially inserted into the STO lattice, as evidenced by X-ray diffraction and X-ray photoelectron spectroscopy. UV–vis spectroscopy indicates a drastic reduction of the bandgap of S:STO from 3.25 eV (indirect) down to 2.14 eV for 10% S:STO, a trend also observed by spectroscopic ellipsometry. The results are confronted to ab initio calculations. Besides bandgap, the valence band level, that is the ionization energy, is determined by ambient-pressure photoemission spectroscopy so that the complete energy diagrams could be plotted. This work paves the way for tuning the bandgap of perovskites in a highly controlled manner for solar energy applications
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