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Al Hoceima Bay, located on Morocco's Mediterranean coast, is a very important ecosystem characterized mainly by seaside tourism and sea fishing. Continental inputs and climate change generally contribute to modifying the environmental parameters that characterize coastal waters. This work aims to characterize the seasonal and spatial variation of the physico-chemical parameters of the surface waters of Al-Hoceima Bay during an annual cycle in the context of global change. Four sampling campaigns (autumn, winter, spring, summer) were conducted during the period 2022-2023 in a sampling network of 15 stations covering all areas of the bay. Surface water samples were collected and analyzed by a multi-parameter instrument. The results show a significant seasonal variation (p < 0.01) for parameters analyzed. Temperatures ranged from 15.59°C to 21.8°C, pH ranged from 7.8 to 8.4. Dissolved oxygen ranged from 3.7 mg/l to 7 mg/l. Salinity ranged from 35.7 g/l to 39.5 g/l. Conductivity ranged from 54 ms/cm to 56.5 ms/cm.

Background: The present study aims to assess the impact of COVID-19 on the epidemiological profile of circulatory, respiratory, and haematological pathologies at the provincial Hospital of Kenitra, Morocco, utilizing a before-and-after comparative approach. Methods: This work consists of a retrospective investigation involving 13,067 cases (excluding cases related to COVID-19) admitted to the provincial hospital of Kenitra between January 1, 2017, and April 30, 2022. Results: The findings revealed a substantial reduction in the overall number of consultations, decreasing from 11,956 consultations before the emergence of COVID-19 to 1,111 consultations afterwards, indicating a 90% decline. Furthermore, there was a notable shift in the gender distribution for respiratory diseases, transitioning from a male predominance with a sex ratio of 2.03 before the COVID-19 pandemic to a female predominance with a sex ratio of 0.83 post-pandemic. Regarding age group distribution, no significant difference was observed between before and after Covid-19. A comparison of the duration of hospital stays before and after Covid-19 pandemic revealed a notable decrease in respiratory (t = 4.96; p< 0.001) and haematological (t = 3.62; p< 0.001) pathologies, with no significant difference for circulatory pathologies. Before COVID-19, patients with circulatory pathologies had a twofold higher risk of mortality compared to other patients, whereas respiratory patients faced a three times higher risk of death. No significant risk of death was associated with haematological pathologies. Following the COVID-19 pandemic, the mortality risk increased for respiratory pathologies but decreased for circulatory pathologies. The risk of mortality for haematological pathologies remained insignificant. Conclusion: the COVID-19 pandemic substantially impacted the epidemiological profile of circulatory, respiratory, and haematological pathologies. [ABSTRACT FROM AUTHOR]

This study investigates the sources and characteristics of PM10 pollution in Tetouan city, Morocco, by employing a combination of chemical mass closure, source-receptor modelling (namely positive matrix factorization, PMF), and air mass trajectory statistical analyses (concentration weighted trajectory, CWT). It provides compelling evidence that using such a combination is a powerful approach for studying the composition and sources of PM10 in the Tetouan region. The PMF analysis identifies four PM10 sources, namely Vehicle Exhaust, Secondary Aerosols, Nitrate + Biomass Burning, and Fresh Sea Salt, with distinct seasonal contributions. CWT analysis reveals the Mediterranean Basin as the primary source region, with influences from populated areas in northern Morocco, southern Europe, and marine emissions. PM10 mass closure highlights the abundance of Dust, Particulate Organic Matter (POM), and Water-Soluble Inorganic Ions (WSI), accounting for the majority of the mass. The low OC/EC ratio advocates that carbonaceous aerosols primarily originate from local traffic emissions. Diagnostic of WSI ratios shows that the [NH4+]/[SO42−] ratio indicated an ammonium-poor environment and suggested an acidic nature of the PM10 aerosols, while the [SO42−]/[NO3−] ratio reflects the combined influence of stationary and mobile sources, with a partial contribution from industrial activities throughout the year. These findings are expected to shed light on the chemical composition, origin of emission sources, and transport pathways of PM10 in the region, contributing to the understanding of air pollution in the south western Mediterranean. [ABSTRACT FROM AUTHOR]

In this paper, thin films of Ag2ZnSnS4 (AZTS) were spin-coated on to ordinary glass substrates and annealed at temperatures ranging from 300 to 375 °C without sulfurization. Characterization techniques like X-ray diffraction (XRD), Scanning Electron Microscope (SEM), Raman Spectroscopy (RS), Energy Dispersive X-ray Spectroscopy (EDS), and UV-Vis spectrophotometry were used to investigate the different physical properties of AZTS thin films. The analyses of XRD and Raman patterns showed that AZTS thin films have a polycrystalline structure with peaks corresponding to the pure tetragonal phase. SEM micrographs showed a nearly uniform, dense, and compact surface morphology for AZTS thin film annealed at 375 °C. The films showed absorption coefficients greater than 104 cm−1 with band gaps found between 1.50 and 1.59 eV. These properties make AZTS thin films a suitable absorber layer for photovoltaic applications. Highlights: Synthesis and characterization of Ag2ZnSnS4 thin films by sol-gel method associated to spin coating technique. Study the effect of annealing temperature on some physical properties. XRD data and Raman scattering measurements indicated the formation of pure Ag2ZnSnS4. Compositional and morphological show that Ag2ZnSnS4 thin films can be suitable for photovoltaic applications. [ABSTRACT FROM AUTHOR]

This study analyses the seasonal distribution in the superficial sediments of the Marchica watershed of trace and major elements, grain size, and total organic carbon. Samples were taken during the wet and dry seasons of 2018 in the mainstream valleys carrying the discharges to the Marchica Lagoon. Ecotoxicological indices (Enrichment Factor, Contamination Factor, Pollution-Load Index) and sedimen-quality guidelines were used to evaluate the ecotoxicological risk. The results revealed during both wet and dry seasons contamination by lead in all stream valleys. The northwest stream valley, characterized by some industrial activities, and the stream valley crossing the abandoned mine were the most polluted by zinc and copper. Minimal pollution for Cr, Co, and Ba was found during both the wet and dry seasons. Despite the restoration actions achieved around the Ramsar site of Marchica lagoon during the last decades, the watershed continues to have a negative impact on this ecosystem. Therefore, an environmental management strategy isnecessary, taking into account the rehabilitation of the abandoned mining sites, the rational use of pesticides and fertilizers in agriculture, and the environmental responsibility of industrial companies, especially those installed before the implementation of the national law on environmental impact studies.

Herein, the cobalt oxide thin films are elaborated by spray pyrolysis technique. The effect of temperature of substrates on several properties of cobalt oxide is studied. The thin layers are characterized by using X‐ray diffraction (XRD), Raman spectrometry (RS), and UV–vis spectrophotometer. The XRD analysis shows that Co3O4 thin layers have been formed along <111> preferential orientation. The RS displays the characteristic vibration modes of cobalt oxide phase, which confirms the formation of a single phase of spinel Co3O4 thin layers. The UV–vis spectrophotometer allows us to investigate the optical properties such as the absorbance, the transmittance, and the optical bandgap. The variation of electrical properties with the variation of temperature deposition confirms the high impact of the effect that study to make the cobalt oxide an important candidate for gas sensor devices. [ABSTRACT FROM AUTHOR]

The semiconductor realization is a very significant stage in gas sensor application. Herein, the Mn3O4 semiconductor was deposited using chemical spray pyrolysis. The effect of deposition temperature on structural, vibrational optical and electrical Mn3O4 thin layers properties were investigated through: X‐ray diffraction, Raman spectroscopy, UV‐visible spectrophotometer, and two points electrometers respectively. The X‐ray diffraction showed the appearance of spinel phase of tetragonal Mn3O4 with strong formation direction along (101) plan and without any secondary phase indicating the formation of pure Mn3O4. The Raman spectroscopy confirmed the results obtained in XRD and certified the high‐quality formation of Mn3O4. In addition, the crystallinity improvement (the increase of crystallite size and the decrease of dislocation density) was caused by the increasing of deposition temperature from 350 °C to 450 °C. Optical properties such as transmittance, absorbance and band gap energy were extracted by UV‐Visible spectrophotometer. Thus, low transmittance, high absorbance and small band gap energy were observed at the highest substrate temperature (450 °C). The electrical conductivity showed good values between 4.83 and 13.89 mS.cm−1. These properties make Mn3O4 an appropriate material to be used as a sensitive layer in gas sensors applications. [ABSTRACT FROM AUTHOR]