5 research outputs found
The Sidi Moussa-Oualidia wetland complex A Bird Paradise between land and sea
No full textThe Sidi Moussa-Oualidia wetland complex is a unique natural ecosystem of significant national and international importance, as designated by the Ramsar Convention. Located in the Moroccan Atlantic zone between El Jadida and Oualidia, this wetland fulfils many functions. The most important are the rich biodiversity, ecological, hydrological, and economic functions are the most important. Regular censuses, carried out during winter between 1993 and 2022 in the Sidi Moussa-Oualidia lagoon complex, made it possible to determine the composition of the waterbird population that frequents this site and to define the status of the various encountered species. Emphasis was also made on the value of this complex, particularly for breeding, based on monitoring work and our unpublished observations. Ninety-six (96) species frequented the site, 51 of which are regular. Waders represent the most dominant group, followed by Laridae and Anatidae. The remaining groups, poorly represented in numbers, total some 29 species, of which twelve (12) are accidental or rare, and nine (9) are mainly observed outside the wintering period. However, some species are particularly interesting, such as the Greater Flamingo, the Eurasian Spoonbill, and the Red-knobbed Coot. Of the 51 regular species in the site, 16 are breeding ones, including species classified as threatened or near-threatened on the global red list (Marbled Teal, Ferruginous Duck) and others considered threatened in Morocco (Purple Swamphen, Red-crested Pochard), rare (Little Tern) or remarkable (Red-knobbed Coot). Despite this ornithological richness, the site is subject to multiple constraints. Creating a specific administrative structure similar to an 'Agency for the development of the Sidi Moussa-Oualidia complex' could be a potential solution for the control, rational management, and sustainable local development
Determination of the structural and optoelectronic properties of InTe cubic monochalcogenide using the WIEN2k code for its application in photovoltaics
No full textThe present study aims to investigate the structural and optoelectronic properties of the InTe cubic monochalcogenide for its application in the field of photovoltaics as a solar reflector, owing to its high optical reflectivity in the visible and ultraviolet range. We focused on this material due to its limited exploration in the literature. These studies were conducted using density functional theory (DFT), employing the WIEN2k software and the full-potential linearized augmented plane wave (FP-LAPW) method. The Local Density Approximation (LDA) was used as an approximation for considering the electron exchange-correlation energy. We optimized the volume to obtain the optimized cell structure based on the minimum energy criterion, which will be used in subsequent calculations. The calculated structural parameters closely align with experimental values. The band structure and density of states (DOS) calculations indicate that the InTe cubic monochalcogenide is metallic, with a total density (TDOS) at the Fermi level of approximately 1.2 states/eV. Optical properties were also calculated for radiations up to 14 eV. The results suggest that this material could be employed as an efficient solar reflector to mitigate heating effects from solar radiation, thereby improving the efficiency of photovoltaic installations through the judicious use of InTe reflective material
First-Principles study of high-temperature thermoelectric performance induced by hydrogenation of ZnAs and CdAs monolayers
No full textMotivated by the improved electronic properties of the isostructural hydrogenated ZnSb monolayers, we investigate the thermoelectric efficiency in the hydrogenated ZnAs and CdAs monolayers (i.e., ZnAsH and CdAsH) at temperatures of 300 K and 900 K using Boltzmann transport theory while accounting for multiple carrier scattering mechanisms. Our results reveal that hydrogenation modifies the band structures of ZnAsH and CdAsH, inducing a transition from metallic to semiconducting behavior (1.89 eV for ZnAsH and 1.23 eV for CdAsH. The cohesive energy, formation energy, phonon spectrum, ab initio molecular dynamics (AIMD), and elastic constants confirm their robust stability. The electronic transport analysis shows that p-type ZnAsH and CdAsH exhibit high Seebeck coefficient of 225.42μV/K and 409.45μV/K respectively, along with high electrical conductivity. Small group velocity, strong anharmonicity, and high scattering rates lead to ultralow lattice thermal conductivities of 3.36(3.74) W/mK for the ZnAsH monolayer and 0.23(0.35) W/mK for the CdAsH monolayer in the x(y) directions. The electronic part of the thermal conductivity is consistent with predictions from the Wiedemann–Franz law. Combining the excellent electronic transport with ultralow lattice thermal conductivity, we achieve optimal ZTs of 0.53 for ZnAsH and 3.72 for CdAsH in the x-direction. These findings suggest that hydrogenated monolayers are promising candidates for thermoelectric (TE) technology
Retroperitoneal cystic lymphangioma coexisting with a uterine fibroid in a 42-year-old woman: A case report
No full textLymphangiomas are rare benign neoplasms traditionally thought to result from congenital lymphatic channel malformations, though they may also be associated with other conditions. Retroperitoneal lymphangiomas account for 1% of all lymphangiomas, and fewer than 200 cases have been reported. A 42-year-old woman was admitted with symptoms of abdominal pain and distension. A computerized tomography (CT) scan showed an abdomino-pelvic mass and a giant uterine myoma. The patient underwent explorative laparotomy and the whole cyst mass was removed along with the uterine myoma. Cystic lymphangiomas are often misdiagnosed because of the vague symptoms and the absence of obvious etiology. A provisional diagnosis can be made with CT but histological examination confirms the diagnosis. Cystic lymphangioma should be included in the differential diagnosis of an ovarian cystic mass. Complete resection can be curative
A First-Principles Study of the Effect of Spin-Orbit Coupling on the Optoelectronic and Magnetic Properties of Manganese Distannide
No full textInternational audienceBased on density functional theory, and using the generalized gradient approximation with spin-orbit coupling (SOC), we studied the electronic, magnetic, and optical properties of the manganese distannide MnSn2. The total energy as a function volume calculation shows that the ferromagnetic state was more energetically stable than the nonmagnetic state. The electronic properties show metallic behavior both with and without SOC. The estimated total magnetic moment including SOC reveals a decrease in the partial magnetic moment. The Mn-3d electronic states contribute significantly to the total density of states and the magnetic properties. The SOC has a clear effect on the optical properties of the MnSn2 compound. Optical parameters including the refractive index, absorption coefficient, reflectivity, optical conductivity, and energy loss function are calculated from the dielectric function. The real and imaginary parts of the dielectric function show that the compound has a metallic behavior. The MnSn2 compound has high reflectance in the infrared range and high absorbance in the ultraviolet range, particularly when SOC is taken into account. The compound is also observed to be more active in the visible region and can be used as a reflector and reducer in solar heating and energy access as well
