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Managing the vast quantities of waste constantly generated by mining activities is one of the major environmental and economic problems facing mankind today. Fluorapatite is separated from the associated gangue minerals by a series of crushing and screening, washing, and flotation processes. These processes produce a significant amount of phosphate sludge, which is stored on the mine site in drift rock and large surface ponds. One possible environmental option is to reuse it as an alternative raw material in ceramics and building materials. Consequently, two phosphate sludges from two different Moroccan towns, Youssoufia and Khouribga, were studied. Due to the complexity of these raw materials resulting from long geological processes, in-depth physical, chemical, mineralogical, and thermal characterization is required. Dry compressed powder pellets were sintered at 900 °C, 1000 °C, and 1100 °C for 2 h. The study focuses on the effect of sintering temperature on mineralogical transformations and ceramic properties such as apparent porosity, water absorption, and mechanical strength. At 1100 °C, a slight increase in density was observed for both phosphate sludges. Water absorption was reduced by 2.51 % in both sludges for pellets sintered at 1100 °C compared to those sintered at 900 °C. Mechanical strength improved significantly, with an increase of about 60 % for samples sintered at 1100 °C, recording 227 N for Youssoufia sludge and 247 N for Khouribga sludge. This work has provided new data on the physical, chemical, mineralogical, and thermal changes in ceramics as the sintering temperature increases. These data will be useful for the manufacture of high-value ceramics.

Spirometry is a pulmonary function test where correct interpretation of the results is crucial for accurate diagnosis of disease. There are online tools to assist in the interpretation of spirometry results; however, as yet none are validated. We evaluated the interpretation accuracy of the Espiro app using pulmonologist interpretations as the gold standard. This is an observational descriptive study in which 118 spirometry results were interpreted by the Espiro app, two pulmonologists, two primary care physicians, and two residents of a primary care training program. We determined the interpretation accuracy of the Espiro app and the concordance of the pattern and severity interpretation between the Espiro app and each of the observers using Cohen’s kappa coefficient (k). We obtained a sensitivity and specificity for the Espiro app of 97.5% (95% confidence interval (CI): 86.8–99.9%) and 94.9% (95%CI: 87.4–98.6%) with pulmonologist 1 and 100% (95%CI: 91.6–100%) and 98.7% (95%CI: 92.9–99.9%) with pulmonologist 2. The concordance for the pattern interpretation was greater than k 0.907, representing almost perfect agreement. The concordance of the severity interpretation was greater than k 0.807, representing substantial to almost perfect agreement. We concluded that the Espiro app is a valid tool for spirometry interpretation.

The aim of the present work is to characterize the phosphate sludge from the area of Youssoufia (rich in CaO ~ 31%) and to study its thermal behavior alone and when mixed with clay from Safi (Morocco). This may contribute to its valorization as an alternative raw material for ceramic industries. The evolution of phases during the thermal treatment of phosphate sludge, clay and sludge–clay mixtures at different mass ratios (25 wt%, 50 wt%, and 75 wt%) was performed at different levels of temperatures from 600 to 1120 °C. Mineralogical analysis by X-ray diffraction (XRD) showed that the sludge mainly consisted of quartz, calcite, dolomite, and francolite. Dolomite and calcite vanished after sludge heating and two new phases were formed, namely akermanite and monticellite. For clay, it mainly consisted of illite, kaolinite, quartz, calcite, and dolomite. After clay sintering at high temperature, a new phase was formed, i.e. anorthite. The effects of the MO/SiO2 ratio (MO = CaO + MgO) in mixtures (clay + sludge) on the crystallization behavior of diopside and fluorapatite, and the disappearance of the akermanite were investigated. The results showed that the crystallization of diopside–fluorapatite increased when the MO/SiO2 ratio increased. Resumen: El objetivo del presente trabajo es caracterizar un lodo de fosfato del área de Youssoufia (rico en CaO ~ 31%) y estudiar su comportamiento térmico tras su mezcla con una arcilla de Safi (Marruecos). Este estudio puede contribuir a su valorización como materia prima alternativa para la industria cerámica. La evolución de las fases minerales durante el tratamiento térmico de lodos de fosfato, arcilla y mezclas de lodos y arcilla en diferentes proporciones de masa (25, 50 y 75% de peso) se realizó a diferentes temperaturas, desde 600 a 1.120 °C. El análisis por difracción de rayos X (DRX) permitió conocer la composición mineralógica del lodo formado principalmente por cuarzo, calcita, dolomita y francolita. La dolomita y la calcita desaparecieron tras el calentamiento del lodo y se formaron 2 nuevas fases, a saber, akermanita y monticellita. En cuanto a la arcilla, el análisis mineralógico evideció la presencia de illita, caolinita, cuarzo, calcita y dolomita como fases mayoritarias. Tras la descomposicón de la arcilla se formó anortita como fase de alta temperatura. Se investigaron los efectos de la relación MO/SiO2 (MO = CaO + MgO) en mezclas (arcilla + lodo) sobre la cristalización de diópsido y fluorapatita y la desaparición de la akermanita. Los resultados mostraron que la cristalización de diopsido-fluorapatita aumentó cuando creció el cociente MO/SiO2.

Understanding sorption isotherms is crucial in food science for optimizing the drying processes, enhancing the shelf-life of food, and maintaining food quality during storage. This study investigated the isotherms of sweet cherry powder (SCP) using the static gravimetric method. The experimental water sorption curves of lyophilized sweet cherry powder were determined at 30°C, 40°C, and 50°C. The curves were then fitted to six isotherm models: Modified GAB, Halsey, Smith, Oswin, Caurie, and Kühn models. To define the energy associated with the sorption process, the isosteric sorption heat, differential entropy, and spreading pressure were derived from the isotherms. Among the six models, the Smith model is the most reliable in predicting the sorption of the cherry powder with a determination coefficient (R2) of 0.9978 and a mean relative error (MRE) ≤1.61. The values of the net isosteric heat and differential entropy for the cherry increased exponentially as the moisture content decreased. The net isosteric heat values varied from 10.63 to 90.97 kJ mol−1, while the differential entropy values varied from 27.94 to 273.39 J. mol−1K−1. Overall, the enthalpy-entropy compensation theory showed that enthalpy-controlled mechanisms could be used to regulate water adsorption in cherry powders.

Le cathétérisme de la veine jugulaire interne est pratiqué largement, aussi bien par les néphrologues que par les chirurgiens, il est devenu une procédure de routine, mais qui peut être associée à de graves complications. La fistule artério-veineuse carotido jugulaire (FCJ) est une complication rare mais potentiellement fatale. Très peu de cas sont rapportés dans la littérature. Nous présentons un cas unique d´un patient avec une FCJ iatrogène, suite à une pose de cathéter d´hémodialyse trois semaines auparavant. Le diagnostic est suspecté cliniquement par la découverte de thrill latéro cervical, et confirmé à l´echodoppler et à l´angiographie. Le patient a eu une cure chirurgicale ouverte avec succès. L´expérience de l´opérateur et l´accompagnement des jeunes internes, en plus de l´utilisation du guidage échographique peut réduire considérablement la survenue de complications lors du cathétérisme veineux jugulaire.

Three phosphate glass compositions, VF1, VF2, and VF3, containing macro and micronutrients with different [K2O/(CaO+MgO)] ratio, were formulated to be used as controlled release fertilizers for tomato crop, depending on their chemical durability in water and their propriety with respect to the standards of controlled-release fertilizers. This study investigated the influence of [K2O/(CaO+MgO)] ratio variation on glass properties. For this, the elaborated glasses have undergone a chemical characterization using inductively coupled plasma atomic emission spectroscopy, a thermal characterization using differential thermal analysis, a physicochemical characterization based on density and molar volume measurements, and a structural characterization using Raman spectroscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction. In addition, the chemical durability was determined by measuring the percentage of weight loss and the pH. Results revealed that the glass structure and composition have the mean role in controlling the release of nutrients in water. By increasing [K2O/(CaO+MgO)] ratio, the dissolution rates of the glasses increased due to the shrinking in the rate of crosslinking between phosphate chains, accompanied with a diminution in transition and crystallization temperatures, and an increase in the molar volume. An agronomic valorization of VF1 and VF2 glass fertilizers, which showed dissolution profiles adequate to the criteria of controlled-release fertilizers, was carried out to evaluate their efficiency on tomato crops. These glass fertilizers improved soil mineral content and tomato performances in comparison to the control and NPK treatments with the distinction of VF2. The results highlight the effectiveness of these smart fertilizers toward their potential large-scale application to improve crop production and quality for high nutritional value foods.

The cement industry has been taking significant steps for years to reduce its carbon footprint by opting for alternative less polluting materials such as sulfo-aluminous cements (CSA). These binders, compared to ordinary Portland cements (OPC), have two advantages: reduction of the CO2 emissions and energy saving because the sintering temperature of CSA cements is much lower than ordinary cement (Portland). The aim of this work is to study the effect of iron oxide on the formation of the ye'elimite phase, which represents the main phase of (CSA).This study details the protocol for the chemical synthesis of ye’elimite containing increasing amounts of iron (general formula: Ca4Al(6-2x)Fe2xSO16 with x = 0.00 to 1.13). The maximum ye’elimite content is reached at a sintering temperature of 1250°C. The presence of iron promotes the formation of cubic ye'elimite at the expense of the orthorhombic phase. The total incorporation of iron in ye’elimite structure is possible when x < 0.12. Beyond this content, the ferritic phase (CaO)2(Al2O3,Fe2O3) appears as a minor phase and its quantity becomes more important with the increase of the percentage of iron introduced in the synthesis. Finally, the electron microscopy allows to observe nanometric grains assembled in larger aggregates.

Les lymphomes malins non-hodgkiniens (LMNH) primitifs du sein sont des tumeurs rares. Leur symptomatologie clinique est polymorphe. L'imagerie médicale est non-spécifique. Le diagnostic peut être évoqué à l'examen cytologique, sa confirmation est toujours histologique. Il s'agit essentiellement de lymphomes de type B, ceux de type NK/T restant rares. Les plus fréquents sont les lymphomes diffus à grandes cellules présentant la particularité de donner des rechutes sous forme d'extension au système nerveux central. Nous rapportons un cas de LMNH primitif bilatéral du sein chez une patiente âgée de 33 ans, révélé par deux nodules mammaires bilatéraux. La mammographie et l'examen extemporané ont évoqué une tumeur phyllode. Le diagnostic du LMNH n'a été fait qu'après examen histologique définitif. Sous chimiothérapie, l'évolution était favorable avec un recul de 15 mois.

Aneurysms of the intra-thoracic subclavian artery (SCA) are rare. They are often revealed by complications. Surgical treatment is always indicated. Endovascular treatment is a less invasive alternative. We report a case of a 60 years-old woman admitted for right chest pain and dysphonia. Laryngoscopy noted a right vocal cord palsy. Chest computed tomography and angiography showed a giant aneurysm of the intra-thoracic right SCA. A resection-ligation of the aneurysm was performed by a supra-clavicular approach. Postoperative course was uneventful. The histology defined an atherosclerotic aneurysm. The patient underwent voice reeducation with partial improvement after six months.