Security and safety remain paramount concerns for both governments and individuals worldwide.In today’s context,the frequency of crimes and terrorist attacks is alarmingly increasing,becoming increasingly intolerable...Security and safety remain paramount concerns for both governments and individuals worldwide.In today’s context,the frequency of crimes and terrorist attacks is alarmingly increasing,becoming increasingly intolerable to society.Consequently,there is a pressing need for swift identification of potential threats to preemptively alert law enforcement and security forces,thereby preventing potential attacks or violent incidents.Recent advancements in big data analytics and deep learning have significantly enhanced the capabilities of computer vision in object detection,particularly in identifying firearms.This paper introduces a novel automatic firearm detection surveillance system,utilizing a one-stage detection approach named MARIE(Mechanism for Realtime Identification of Firearms).MARIE incorporates the Single Shot Multibox Detector(SSD)model,which has been specifically optimized to balance the speed-accuracy trade-off critical in firearm detection applications.The SSD model was further refined by integrating MobileNetV2 and InceptionV2 architectures for superior feature extraction capabilities.The experimental results demonstrate that this modified SSD configuration provides highly satisfactory performance,surpassing existing methods trained on the same dataset in terms of the critical speedaccuracy trade-off.Through these innovations,MARIE sets a new standard in surveillance technology,offering a robust solution to enhance public safety effectively.展开更多
An ethnobotanical survey was conducted in the city of Meknès over a period of two years, from 2009 to 2011 with 1000 people (615 women, 385 men). Through the questionnaire, schedules were established to collect i...An ethnobotanical survey was conducted in the city of Meknès over a period of two years, from 2009 to 2011 with 1000 people (615 women, 385 men). Through the questionnaire, schedules were established to collect information on the use of therapeutic medicinal plants by the local population. This research has focused primarily on the general population, herbalists and healers. The present investigation has enumerated 194 species distributed in 165 genera and 72 families. The most represented families are Lamiaceae (18%), the Aseraceae, (17%), the Apiaceae (14%) and the Fabaceae (10%). The results of the survey show that 54% of individuals use both herbal medicine and modern medicine, 26% of individuals use herbs and 20% use modern medicine. We are interested in the use of plants in different ages and sexes. We report that 31% of the population is aged between 51 and 60 years, 29% between 41 and 50 years, 23% between 31 and 40 years, 10% between 21 and 30 years, 3% less than 20 years and 4 % > 60 years. We note the predominance of women over men. Women use up to 61% against 39% of men. The analysis of our results shows that herbal medicine takes a place in the self-medication of the population studied. However, we emphasize an important point: Ignorance of toxic plants, in fact, only 19% of the target population recognizes these plants.展开更多
In this paper,we have calculated the structural,electronic,and optical properties of chalcogenide stannite Cu_(2)CdSnX4(X=S,Se,Te) materials.The calculations are based on the density functional theory (DFT) method and...In this paper,we have calculated the structural,electronic,and optical properties of chalcogenide stannite Cu_(2)CdSnX4(X=S,Se,Te) materials.The calculations are based on the density functional theory (DFT) method and are performed using the Cambridge sequential total energy package (CASTEP) code included in the Biovia Material Studio 20 software.All optical properties have been studied in a domain that extends energetically from 10 meV to 40 eV.Our results show that Cu_(2)CdSnX4(X=S,Se,Te) stannite exhibits absorption in the visible region,the refractive index decreases with increasing energy,and the refractive index values are n=3.2,3.73 and 3.75 for Cu_(2)CdSnS_(4),Cu_(2)CdSnSe_(4)and Cu_(2)CdSnTe_(4),respectively.They show also high conductivity,which implies that this material is promising for solar cells.These results argue in favor of the use of these materials in various potential applications.The density of state,band structures,and structural properties of Cu_(2)CdSnX4(X=S,Se,and Te) stannite are also studied in this work.展开更多
The present study focuses on the flow of a yield-stress(Bingham)nanofluid,consisting of suspended Fe3O4 nanoparticles,subjected to a magnetic field in a backward-facing step duct(BFS)configuration.The duct is equipped...The present study focuses on the flow of a yield-stress(Bingham)nanofluid,consisting of suspended Fe3O4 nanoparticles,subjected to a magnetic field in a backward-facing step duct(BFS)configuration.The duct is equipped with a cylindrical obstacle,where the lower wall is kept at a constant temperature.The yield-stress nanofluid enters this duct at a cold temperature with fully developed velocity.The aim of the present investigation is to explore the influence of flow velocity(Re=10 to 200),nanoparticle concentration(ϕ=0 to 0.1),magnetic field intensity(Ha=0 to 100),and its inclination angle(γ=0 to 90)and nanofluid yield stress(Bn=0 to 20)on the thermal and hydrodynamic efficiency inside the backward-facing step.The numerical results have been obtained by resolving the momentum and energy balance equations using the Galerkin finite element method.The obtained results have indicated that an increase in Reynolds number and nanoparticle volume fraction enhances heat transfer.In contrast,a significant reduction is observed with an increase in Hartmann and Bingham numbers,resulting in quasi-immobilization of the fluid under the magnetic influence and radical solidification of this type of fluid,accompanied by the suppression of the vortex zone downstream of the cylindrical obstacle.This study sheds light on the complexity of this magnetically influenced fluid,with potential implications in various engineering and materials science fields.展开更多
Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and...Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and hierarchical.Due to their porous nature,interfacial compatibility,and electrical conductivity,biomass materials hold significant potential as EMI shielding materials.Despite concerted efforts on the EMI shielding of biomass materials have been reported,this research area is still relatively new compared to traditional EMI shielding materials.In particular,a more comprehensive study and summary of the factors influencing biomass EMI shielding materials including the pore structure adjustment,preparation process,and micro-control would be valuable.The preparation methods and characteristics of wood,bamboo,cellulose and lignin in EMI shielding field are critically discussed in this paper,and similar biomass EMI materials are summarized and analyzed.The composite methods and fillers of various biomass materials were reviewed.this paper also highlights the mechanism of EMI shielding as well as existing prospects and challenges for development trends in this field.展开更多
The stabilization problem of second-order bilinear systems with time delay is investigated.Feedback controls are chosen so that the strong and exponential stabilization of the system is ensured.The obtained results ar...The stabilization problem of second-order bilinear systems with time delay is investigated.Feedback controls are chosen so that the strong and exponential stabilization of the system is ensured.The obtained results are illustrated by wave and beam equations with simulation.展开更多
In Morocco,hydrological and hydrobiological surveys of wadis,river and stream are rare.In this research,we plan to attempt to characterize the physico-chemistry of surface waters of sixteen stations sampled at the lev...In Morocco,hydrological and hydrobiological surveys of wadis,river and stream are rare.In this research,we plan to attempt to characterize the physico-chemistry of surface waters of sixteen stations sampled at the level of the Sebou basin during the period 2013-2023.The diagnosis showed that this natural watercourse is highly enriched in oce-anic salts.A large fluctuation in the chemical nature of the waters was recorded,as well as electrical conductivity(EC),which oscillates between 629 and 22,766μS/cm.Hydrogen Potential ranges from 8.01 to 8.79 while remaining basic.Nitrate(NO3-)concentrations range from a maximum of 886.9 mg/l to a minimum of 0.24 mg/l.Similarly,the am-monium concentration varies from 0.04 to 15.34 mg/l.It was also noted that the waters were very rich in chloride ions(860.27 to 145.55 mg/l),in sodium Na+ion(51 to 2,530 mg/l),in sulfate ions SO4--(441.4 to 37.62 mg/l),in calcium ions Ca2+(97.6 to 1,072.8 mg/l)and in magnesium ions Mg2+(631.2 to 17.28 mg/l)which explains the high hardness of these waters.The concentrations of potassium ions(K+)range from 2.54 to 17.55 mg/l.The high alkalinity is due to the high concentrations of bicarbonate ions(75.64 to 362.34 mg/l).Our study concludes that the waters of the Sebou re-main below the irrigation threshold authorized by Moroccan law when moving away from its Atlantic estuary.They are too degraded and we suggest that urban and industrial wastewater be pre-treated as a priority to reduce natural environment.展开更多
The Upper Cretaceous successions of Wadi Umm-Khayshar,southern Galala Plateau,North Eastern Desert,Egypt,are composed of highly diversified faunas and subdivided from base to top into the Galala(Middle-Late Cenomanian...The Upper Cretaceous successions of Wadi Umm-Khayshar,southern Galala Plateau,North Eastern Desert,Egypt,are composed of highly diversified faunas and subdivided from base to top into the Galala(Middle-Late Cenomanian),Maghra El Hadida(Latest Cenomanian-Late Turonian),Matulla(Coniacian-Santonian),and Sudr(Campanian-Maastrichtian)formations.Five ammonite biozones are recorded in the studied section:Neolobites vibrayeanus,Vascoceras cauvini(late Cenomanian),Vascoceras proprium,Choffaticeras segne,and Coilopoceras requienianum(Turonian)zones.The paleoenvironments of the Upper Cretaceous succession are interpreted based on detailed study and microfacies analysis that reflect a deposition in a homoclinal ramp platform ranging from intertidal to deep subtidal.The paleoecology of the Cenomanian-Turonian succession in the studied section is explained based on a detailed study of macrofaunal associations and sedimentary facies.Quantitative analysis(Q-mode cluster analysis,using the Raup-Crick Paired group method)of 1029 macrobenthic specimens,including 45 species of mollusks and echinoids yielded five macrofaunal associations(A-E)that are described and interpreted as remnants of communities.The nektonic elements are represented by 235 cephalopod specimens of 20 species;heatmap cluster analyses show the distribution of these specimens during the Upper Cenomanian-Turonian stages.Environmental parameters(substrate consistency,rate of sedimentation,water energy,surface-water productivity,and oxygen availability)controlled the distribution of the studied macrofauna.The five associations are divided into two major groups:low-stress associations(A,B,C,and D),and a highstress association(E).The low stress associations are recorded from two different habitats:(1)a high-energy,firm substrate habitat,dominated by epifaunal bivalves,large epifaunal gastropods and a regular echinoid;(2)a low-energy,soft substrate habitat dominated by infaunal bivalves and echinoids.The high stress association is dominated by only two species and recorded from a high-energy shoal environment during a regression phase.A detailed study of macrobenthos and cephalopods provides a good paleoecological understanding of Cenomanian-Turonian succession in the Wadi Umm-Khayshar section.展开更多
Geothermal exploration and development in North Africa have advanced significantly,driven by the region's rich geothermal resources and rising energy demand.The countries of Mauritania,Morocco,Algeria,Tunisia,Liby...Geothermal exploration and development in North Africa have advanced significantly,driven by the region's rich geothermal resources and rising energy demand.The countries of Mauritania,Morocco,Algeria,Tunisia,Libya,and Egypt are located near tectonic plate boundaries(African and Eurasian plates),giving them substantial geothermal potential.Various exploration activities,including geological surveys and geophysical studies,have been conducted to assess geothermal reservoirs and identify suitable development sites.This article reviews the progress made in geothermal exploration across the region,highlighting the key activities undertaken to evaluate geothermal resources.It also explores how government policies have played a critical role either in fostering or in freezing geothermal development.The different conducted assessments such as analyzing geological structures,hydrothermal systems,and subsurface temperatures lead to identify suitable sites for geothermal development and improve the understanding of subsurface conditions and ongoing projects.Today,some countries in North Africa are positioning themselves to become important players in the global geothermal energy landscape,and with continued investment and concerted efforts,the region has the potential to emerge as a prominent player in the global geothermal energy landscape.展开更多
Seyitgazi and Han districts,located in the south of Eskişehir in Central Anatolia,in western Türkiye,host interesting landforms,such as steep slopes,mesas and butte structures,fault-guided slopes,valleys,fairy ch...Seyitgazi and Han districts,located in the south of Eskişehir in Central Anatolia,in western Türkiye,host interesting landforms,such as steep slopes,mesas and butte structures,fault-guided slopes,valleys,fairy chimneys,castle koppies,pillars,weathered rock blocks,perched rocks,cavernous weathering features,grooves,and gnammas,formed on tuffs in semi-arid to semi-humid climatic conditions,as well as geoarchaeological remains belonging to various civilisations,primarily the Phrygians(including rock-cut tombs and settlements,fortresses,rock churches,façades,altars,and niches).This study aims at identifying these remarkable landforms that host cultural heritage and revealing the geoheritage value and geotourism potential of the region.The data obtained from the fieldwork were evaluated using the methodology proposed by Pereira and Pereira in 2010,and 26 geomorphosites were selected from 61 potential sites using this method.The analysis results revealed that although the region hosts numerous geomorphosites with high scientific,cultural,aesthetic,and ecological value,the overall levels of protection and touristic use of these landforms are generally low.Indeed,the area,which has the potential to be an important tourism region in the future,faces problems such as infrastructure deficiencies,transportation difficulties,lack of promotion,weaknesses in accommodation services,and destruction of geoheritage.These results highlight the importance of implementing sustainable geotourism strategies that are compatible with the region’s unique geoheritage.In this respect,this study is among the first to comprehensively inventory and assess the geomorphosites of Mountainous Phrygia,contributing to regional geoconservation and sustainable tourism development.展开更多
Predictive maintenance often involves imbalanced multivariate time series datasets with scarce failure events,posing challenges for model training due to the high dimensionality of the data and the need for domain-spe...Predictive maintenance often involves imbalanced multivariate time series datasets with scarce failure events,posing challenges for model training due to the high dimensionality of the data and the need for domain-specific preprocessing,which frequently leads to the development of large and complex models.Inspired by the success of Large Language Models(LLMs),transformer-based foundation models have been developed for time series(TSFM).These models have been proven to reconstruct time series in a zero-shot manner,being able to capture different patterns that effectively characterize time series.This paper proposes the use of TSFM to generate embeddings of the input data space,making them more interpretable for machine learning models.To evaluate the effectiveness of our approach,we trained three classical machine learning algorithms and one neural network using the embeddings generated by the TSFM called Moment for predicting the remaining useful life of aircraft engines.We test the models trained with both the full training dataset and only 10%of the training samples.Our results show that training simple models,such as support vector regressors or neural networks,with embeddings generated by Moment not only accelerates the training process but also enhances performance in few-shot learning scenarios,where data is scarce.This suggests a promising alternative to complex deep learning architectures,particularly in industrial contexts with limited labeled data.展开更多
This study evaluates the impact of heavy metals(zinc,copper and cadmium)on the development and metabolic responses of the maize(Zea mays)variety“Torro Plus”.Seeds were cultivated on MS medium enriched with progressi...This study evaluates the impact of heavy metals(zinc,copper and cadmium)on the development and metabolic responses of the maize(Zea mays)variety“Torro Plus”.Seeds were cultivated on MS medium enriched with progressively higher concentrations of heavy metals(50,100 and 150μM),and plants were analyzed after 21 days.The results show a significant reduction in morphological parameters,notably an 87.28%decrease in the fresh weight of aerial parts and a 69.93%decrease in the fresh weight of roots under 150μM of Cd.Chlorophyll a,b and total content also decreased drastically,reaching a maximum reduction of 74.31%under Cd(150μM).In contrast,secondary metabolites such as proline and flavonoids increased,with a maximum proline accumulation of 0.71 mg/g under Cu(150μM)and a flavonoid concentration reaching 176.33 mg/g under Cu(100μM).These results show mechanisms of adaptation to stress,notably the accumulation of flavonoids and proline,while highlighting the increased toxicity of cadmium at high doses.These data are promising for applications in phytoremediation and sustainable agriculture.This study provides important data on the physiological and biochemical responses of plants to heavy metals and opens up prospects for phytoremediation applications.展开更多
Oasis soils in Tunisia are characterized by low soil organic carbon(SOC)stocks,primarily due to their coarse texture and intensive irrigation practices.In the Gataaya Oasis,soils receive 3.000 to 4.000 L/m^(2) annuall...Oasis soils in Tunisia are characterized by low soil organic carbon(SOC)stocks,primarily due to their coarse texture and intensive irrigation practices.In the Gataaya Oasis,soils receive 3.000 to 4.000 L/m^(2) annually through submersion irrigation,leading to a rapid decline in SOC stocks.Despite their sandy texture,which promotes good water infiltration,these soils are enriched with clay,dissolved materials,and fertilizers in deeper horizons.This study aimed to assess SOC content in the Gataaya Oasis soils,investigate the transport of labile carbon in drainage water,and clarify the destiny of this transported carbon.Soil samples were collected systematically at three depths(0–10,10–20,and 20–30 cm),focusing on the top 30 cm depth,which is most affected by amendments.Two sampling points(P1 and P2)were selected,i.e.,P1 profile near the trunk of date palms(with manure input)and P2 profile between two adjacent date palms(without manure input).Water samples were collected from drainage systems within the oasis(W1,W2,and W3)and outside the oasis(W4).A laboratory experiment simulating manure application and irrigation was conducted to complement field observations.Physical-chemical analyses revealed a significant decrease in SOC stocks with soil depths.In P1 profile,SOC stocks declined from 17.71 t/hm^(2) at the 0–10 cm depth to 7.80 t/hm^(2) at the 20–30 cm depth.In P2 profile,SOC stocks were lower,decreasing from 6.73 t/hm^(2) at the 0–10 cm depth to 3.57 t/hm^(2) at the 20–30 cm depth.Labile carbon content in drainage water increased outside the oasis,with chemical oxygen demand(COD)values rising from 73 mg/L in W1 water sample to 290 mg/L in W4 water sample,indicating cumulative leaching effects from surrounding oases.The laboratory experiment confirmed field observations,showing a decline in soil organic matter(SOM)content from 3.27%to 2.62%after 12 irrigations,highlighting the vulnerability of SOC stocks to intensive irrigation.This study underscores the low SOC stocks in the Gataaya Oasis soils and their rapid depletion under successive irrigations.The findings provide insights into the dynamics of labile carbon transport and its contribution to regional carbon cycling,offering valuable information for sustainable soil management and ecological protection in arid ecosystems.展开更多
African traditional medicine is characterized by its rich ethnobotanical heritage,diverse healing practices,and the integration of different culture influences.Similarly,traditional Chinese medicine(TCM)is deeply root...African traditional medicine is characterized by its rich ethnobotanical heritage,diverse healing practices,and the integration of different culture influences.Similarly,traditional Chinese medicine(TCM)is deeply rooted in ancient philosophies,emphasizing balance,holistic diagnostics,and herbal formulations.Despite their geographical distance,both systems share historical and cultural parallels,particularly in their therapeutic principles,use of natural remedies,and holistic approaches to health.Combining these two medical traditions would offer a comprehensive perspective on healing,particularly through herbal medicine,diagnostic methods,and variations in preparation techniques and applications.As an example,Tetraena gaetula is a perennial plant endemic to the arid and semi-arid regions of Morocco,widely used in local medicine to treat diabetes,dermatological conditions,and liver,kidney,and stomach ailments,as well as in veterinary care.The unique properties of Tetraena gaetula could enhance research on multi-faceted approaches of Chinese medicine including herbal methodologies and local applications,contributing to the development of innovative medicines or therapies that integrate the strengths of both traditions.This paper explores potential strategies for integrating African traditional medicine and TCM,highlighting both the opportunities-such as the potential for new medicine discoveries,expanded treatment options,and cross-cultural knowledge exchange-and the challenges,including differences in regulatory frameworks,scientific validation,and the preservation of traditional knowledge.展开更多
This study investigates the physical properties of the rare earth XFes(X=Sm,Dy,or Nd)materials.Our analysis encompasses these compounds'structural,electronic,thermodynamic,and optical characteristics using density...This study investigates the physical properties of the rare earth XFes(X=Sm,Dy,or Nd)materials.Our analysis encompasses these compounds'structural,electronic,thermodynamic,and optical characteristics using density functional theory(DFT)as implemented in the Wien2k software package.The GGA+SOC+U method was employed to determine the exchange-correlation potential.Our results show that the XFes materials exhibit metallic behavior and exhibit ferromagnetic(FM)phases.Notably,our optical analysis reveals a strong absorption response in the UV region,with characteristic absorption curves and peak intensities varying across the different materials.We also investigated the thermodynamic properties of the materials,finding that the entropy increases exponentially with temperature as the materials transition from a ground state to a more disordered and amorphous state.Our thermodynamic results show that the Debye temperature decreases for all three materials,with DyFes exhibiting the highest Debye temperature at 0 K(307 K),followed by NdFes(298 K),and then SmFes(288 K).This indicates that each material has a unique thermal energy barrier to overcome before vibrations occur.As the temperature increases,the Debye temperature decreases,reflecting a decrease in the thermal energy required to induce vibrations.The differences in Debye temperature values between the three materials may suggest differences in their lattice structures or phonon properties,highlighting the importance of understanding these thermal properties for developing new materials and technologies.展开更多
This research study focuses on predicting ferrofluids’viscosity using machine learning models,artificial neural networks(ANNs),and random forests(RFs)incorporating key parameters;ferrofluid type,concentration of magn...This research study focuses on predicting ferrofluids’viscosity using machine learning models,artificial neural networks(ANNs),and random forests(RFs)incorporating key parameters;ferrofluid type,concentration of magnetic nanoparticles,temperature,and magnetic field intensity as inputs.A comprehensive database of 333 datasets sourced from various literatures was utilized for training and validating models.The ANN model demonstrated high accuracy,with root mean square error(RMSE)values below 0.033 and mean absolute percentage error(MAPE)not exceeding 3.01%,while the RF model achieved similar accuracy with RMSE under 0.052 and MAPE below 4.82%.Maximum deviations observed were 9.14%for ANN and 16.48%for RF,confirming that both models accurately learned the underlying patterns without overestimating viscosity.Additionally,the ANN model successfully captured intricate physical relationships between input parameters and viscosity when it was used to predict viscosity for random input data,confirming its ability to generalize beyond the training dataset.The RF model,however,showed limitations in extrapolating beyond the range of the training data.This research study demonstrates machine learning models’effectiveness in capturing intricate relationships governing the viscosity of ferrofluid for different types,paving the way for an improved understanding of ferrofluid’s viscosity behavior.展开更多
The aim of this research is to assess the energy potential of cow dung and corn cob inputs,with a view to estimating their biogas potential.The inputs were characterized in the microbiology laboratory of the National ...The aim of this research is to assess the energy potential of cow dung and corn cob inputs,with a view to estimating their biogas potential.The inputs were characterized in the microbiology laboratory of the National Control Office Quality in Matoto,Conakry.The experiment to produce methane from cow dung and maize cob was carried out at the Applied Research in Natural Sciences Laboratory of the University of Kindia(UK)using the following equipment:Three digesters were each connected to an air chamber(gasometer)by means of flexible pipes 8 mm in diameter,connected by clamps,liquid adhesives,valves and Teflon.This research focused on determining the quantity of biogas contained in each type of substrate(cow dung,maize cob and their mixture).Three experiments on the methanization of these inputs were carried out,with anaerobic digestion lasting 27 days,in a temperature range of 27℃ to 31℃(mesophilic range).The results were as follows:maize cob 28.4 L,cow dung 22.6 L and codigestion 38.7 L.These results compared with similar studies revealed a coincidence.展开更多
A classification of multipartite entanglement is introduced for pure and mixed states.The classification is based on the distribution of entanglement between the qubits of a given system,with a mathematical framework ...A classification of multipartite entanglement is introduced for pure and mixed states.The classification is based on the distribution of entanglement between the qubits of a given system,with a mathematical framework used to characterize fully entangled states.Then we use current machine learning and deep learning techniques to automatically classify a random state of two,three,and four qubits without the need to compute the amount of the different types of entanglement in each run;rather this is done only in the learning process.The technique shows high,near-perfect,accuracy in the case of pure states.As expected,this accuracy drops,more or less,when dealing with mixed states and when increasing the number of parties involved.展开更多
The global reheating observed in these last years is followed with a change of rainfalls bunches at the global and regional area.The floods frequency increasing,dangerously impacts the socio-economic activities of sev...The global reheating observed in these last years is followed with a change of rainfalls bunches at the global and regional area.The floods frequency increasing,dangerously impacts the socio-economic activities of several countries throughout the world.Indeed,for Niger as a country located in West Africa where the majority of the population existence depends on the agricultural and pastoral activities,this change of rainfalls bunches may have unwanted consequences.The aim of this work is to analyze the evolution and trend of rainfall in Niger during the period 2008-2024 compared to the period 1971-2000 characterized by episodes of drought.To achieve the objective of this work,annual data of rainfalls and the number of rainy days from four meteorological stations representative of the four major climatic zones of Niger are used.These are the station of Agadez(in Sahelian zone),the station of Tahoua(in mid Sahelian and Saharan zone),the station of Niamey(in Sahelian zone)and the station of Gaya(in mid Sahelian and Sudden zone).Thus,the standardized index of Lamb(1982)and the least squares method are respectively used to analyze the variability of the interannual rainfalls and their tendency.The results obtained show a significant improvement in rainfall in the four climatic zones compared to the period from 1971 to 2000,and especially in the Nigerien Sahara where 88.2%of the years were wet.The latitudinal gradient South-North of the rainfalls has known an upgrading going from 1 mm/km during the period of 1971-2000 to 1.26 mm/km during the period of 2008-2024.Our results also show that this improvement in rainfall is linked to heavy rainfall events which are the cause of floods observed mainly during wet years(2010,2012,2013,2017,2019 and 2024).Finally,the results show that,excepting the Sahel-Niger,the other climatic zones are experiencing an increasing trend in rainfall.Therefore,in the face of current climate change,West African countries must mobilize to put in place a strategy to mitigate the consequences of heavy rainfall.展开更多
Since it first appeared in 2022,the phenomenon referred to as Colony Collapse Disorder(CCD)has affected several regions of Morocco to varying degrees.In order to assess the possible impact of pesticides on the appeara...Since it first appeared in 2022,the phenomenon referred to as Colony Collapse Disorder(CCD)has affected several regions of Morocco to varying degrees.In order to assess the possible impact of pesticides on the appearance of this syndrome,we conducted a study aimed at evaluating the impact of pesticide use on the emergence of this syndrome through a year-long survey involving 160 beekeepers in the Beni Mellal–Khenifra Region(BKR)who also experienced an unprecedented desertion of hives during the same period.The majority of surveyed beekeepers practice mixed(45%)or migratory beekeeping(42%)and provide supplementary feeding(83.75%)to support their bees.Nearly 37.5%of the hives are located near crops treated with pesticides,exposing the bees to these chemicals.The results showed that the majority of beekeepers reported a cessation of queen laying(74.38%),high mortality rates among worker bees(81.25%),drones(65.63%),and queens(61.88%).Abnormal behaviors such as immobility with trembling(42.50%),reduced flights(47.50%),and disoriented navigation(28.75%)were also observed.Correlation analyses indicate that proximity to treated crops significantly increases the risk of queen laying cessation(Odds Ratio 6.0)and a reduction in waggle dances(Odds Ratio 2.41).Extended foraging flights show a borderline statistical significance(Odds Ratio 2.33),suggesting a disruption of natural food sources.These results highlight the potential impact of pesticides on colony health and bee behavior,pointing out the need to adapt beekeeping practices and implement protective measures against pesticides.展开更多
文摘Security and safety remain paramount concerns for both governments and individuals worldwide.In today’s context,the frequency of crimes and terrorist attacks is alarmingly increasing,becoming increasingly intolerable to society.Consequently,there is a pressing need for swift identification of potential threats to preemptively alert law enforcement and security forces,thereby preventing potential attacks or violent incidents.Recent advancements in big data analytics and deep learning have significantly enhanced the capabilities of computer vision in object detection,particularly in identifying firearms.This paper introduces a novel automatic firearm detection surveillance system,utilizing a one-stage detection approach named MARIE(Mechanism for Realtime Identification of Firearms).MARIE incorporates the Single Shot Multibox Detector(SSD)model,which has been specifically optimized to balance the speed-accuracy trade-off critical in firearm detection applications.The SSD model was further refined by integrating MobileNetV2 and InceptionV2 architectures for superior feature extraction capabilities.The experimental results demonstrate that this modified SSD configuration provides highly satisfactory performance,surpassing existing methods trained on the same dataset in terms of the critical speedaccuracy trade-off.Through these innovations,MARIE sets a new standard in surveillance technology,offering a robust solution to enhance public safety effectively.
文摘An ethnobotanical survey was conducted in the city of Meknès over a period of two years, from 2009 to 2011 with 1000 people (615 women, 385 men). Through the questionnaire, schedules were established to collect information on the use of therapeutic medicinal plants by the local population. This research has focused primarily on the general population, herbalists and healers. The present investigation has enumerated 194 species distributed in 165 genera and 72 families. The most represented families are Lamiaceae (18%), the Aseraceae, (17%), the Apiaceae (14%) and the Fabaceae (10%). The results of the survey show that 54% of individuals use both herbal medicine and modern medicine, 26% of individuals use herbs and 20% use modern medicine. We are interested in the use of plants in different ages and sexes. We report that 31% of the population is aged between 51 and 60 years, 29% between 41 and 50 years, 23% between 31 and 40 years, 10% between 21 and 30 years, 3% less than 20 years and 4 % > 60 years. We note the predominance of women over men. Women use up to 61% against 39% of men. The analysis of our results shows that herbal medicine takes a place in the self-medication of the population studied. However, we emphasize an important point: Ignorance of toxic plants, in fact, only 19% of the target population recognizes these plants.
基金supported by the University Sultan Moulay Slimane,Beni Mellal,Morocco。
文摘In this paper,we have calculated the structural,electronic,and optical properties of chalcogenide stannite Cu_(2)CdSnX4(X=S,Se,Te) materials.The calculations are based on the density functional theory (DFT) method and are performed using the Cambridge sequential total energy package (CASTEP) code included in the Biovia Material Studio 20 software.All optical properties have been studied in a domain that extends energetically from 10 meV to 40 eV.Our results show that Cu_(2)CdSnX4(X=S,Se,Te) stannite exhibits absorption in the visible region,the refractive index decreases with increasing energy,and the refractive index values are n=3.2,3.73 and 3.75 for Cu_(2)CdSnS_(4),Cu_(2)CdSnSe_(4)and Cu_(2)CdSnTe_(4),respectively.They show also high conductivity,which implies that this material is promising for solar cells.These results argue in favor of the use of these materials in various potential applications.The density of state,band structures,and structural properties of Cu_(2)CdSnX4(X=S,Se,and Te) stannite are also studied in this work.
文摘The present study focuses on the flow of a yield-stress(Bingham)nanofluid,consisting of suspended Fe3O4 nanoparticles,subjected to a magnetic field in a backward-facing step duct(BFS)configuration.The duct is equipped with a cylindrical obstacle,where the lower wall is kept at a constant temperature.The yield-stress nanofluid enters this duct at a cold temperature with fully developed velocity.The aim of the present investigation is to explore the influence of flow velocity(Re=10 to 200),nanoparticle concentration(ϕ=0 to 0.1),magnetic field intensity(Ha=0 to 100),and its inclination angle(γ=0 to 90)and nanofluid yield stress(Bn=0 to 20)on the thermal and hydrodynamic efficiency inside the backward-facing step.The numerical results have been obtained by resolving the momentum and energy balance equations using the Galerkin finite element method.The obtained results have indicated that an increase in Reynolds number and nanoparticle volume fraction enhances heat transfer.In contrast,a significant reduction is observed with an increase in Hartmann and Bingham numbers,resulting in quasi-immobilization of the fluid under the magnetic influence and radical solidification of this type of fluid,accompanied by the suppression of the vortex zone downstream of the cylindrical obstacle.This study sheds light on the complexity of this magnetically influenced fluid,with potential implications in various engineering and materials science fields.
基金National Natural Science Foundation of China(32201491)Young Elite Scientists Sponsorship Program by CAST(2023QNRC001)The authors extend their appreciation to the Deanship of Scientific Research at Northern Border University,Arar,KSA for funding this research work through the project number“NBU-FPEJ-2024-1101-02”.
文摘Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and hierarchical.Due to their porous nature,interfacial compatibility,and electrical conductivity,biomass materials hold significant potential as EMI shielding materials.Despite concerted efforts on the EMI shielding of biomass materials have been reported,this research area is still relatively new compared to traditional EMI shielding materials.In particular,a more comprehensive study and summary of the factors influencing biomass EMI shielding materials including the pore structure adjustment,preparation process,and micro-control would be valuable.The preparation methods and characteristics of wood,bamboo,cellulose and lignin in EMI shielding field are critically discussed in this paper,and similar biomass EMI materials are summarized and analyzed.The composite methods and fillers of various biomass materials were reviewed.this paper also highlights the mechanism of EMI shielding as well as existing prospects and challenges for development trends in this field.
文摘The stabilization problem of second-order bilinear systems with time delay is investigated.Feedback controls are chosen so that the strong and exponential stabilization of the system is ensured.The obtained results are illustrated by wave and beam equations with simulation.
文摘In Morocco,hydrological and hydrobiological surveys of wadis,river and stream are rare.In this research,we plan to attempt to characterize the physico-chemistry of surface waters of sixteen stations sampled at the level of the Sebou basin during the period 2013-2023.The diagnosis showed that this natural watercourse is highly enriched in oce-anic salts.A large fluctuation in the chemical nature of the waters was recorded,as well as electrical conductivity(EC),which oscillates between 629 and 22,766μS/cm.Hydrogen Potential ranges from 8.01 to 8.79 while remaining basic.Nitrate(NO3-)concentrations range from a maximum of 886.9 mg/l to a minimum of 0.24 mg/l.Similarly,the am-monium concentration varies from 0.04 to 15.34 mg/l.It was also noted that the waters were very rich in chloride ions(860.27 to 145.55 mg/l),in sodium Na+ion(51 to 2,530 mg/l),in sulfate ions SO4--(441.4 to 37.62 mg/l),in calcium ions Ca2+(97.6 to 1,072.8 mg/l)and in magnesium ions Mg2+(631.2 to 17.28 mg/l)which explains the high hardness of these waters.The concentrations of potassium ions(K+)range from 2.54 to 17.55 mg/l.The high alkalinity is due to the high concentrations of bicarbonate ions(75.64 to 362.34 mg/l).Our study concludes that the waters of the Sebou re-main below the irrigation threshold authorized by Moroccan law when moving away from its Atlantic estuary.They are too degraded and we suggest that urban and industrial wastewater be pre-treated as a priority to reduce natural environment.
文摘The Upper Cretaceous successions of Wadi Umm-Khayshar,southern Galala Plateau,North Eastern Desert,Egypt,are composed of highly diversified faunas and subdivided from base to top into the Galala(Middle-Late Cenomanian),Maghra El Hadida(Latest Cenomanian-Late Turonian),Matulla(Coniacian-Santonian),and Sudr(Campanian-Maastrichtian)formations.Five ammonite biozones are recorded in the studied section:Neolobites vibrayeanus,Vascoceras cauvini(late Cenomanian),Vascoceras proprium,Choffaticeras segne,and Coilopoceras requienianum(Turonian)zones.The paleoenvironments of the Upper Cretaceous succession are interpreted based on detailed study and microfacies analysis that reflect a deposition in a homoclinal ramp platform ranging from intertidal to deep subtidal.The paleoecology of the Cenomanian-Turonian succession in the studied section is explained based on a detailed study of macrofaunal associations and sedimentary facies.Quantitative analysis(Q-mode cluster analysis,using the Raup-Crick Paired group method)of 1029 macrobenthic specimens,including 45 species of mollusks and echinoids yielded five macrofaunal associations(A-E)that are described and interpreted as remnants of communities.The nektonic elements are represented by 235 cephalopod specimens of 20 species;heatmap cluster analyses show the distribution of these specimens during the Upper Cenomanian-Turonian stages.Environmental parameters(substrate consistency,rate of sedimentation,water energy,surface-water productivity,and oxygen availability)controlled the distribution of the studied macrofauna.The five associations are divided into two major groups:low-stress associations(A,B,C,and D),and a highstress association(E).The low stress associations are recorded from two different habitats:(1)a high-energy,firm substrate habitat,dominated by epifaunal bivalves,large epifaunal gastropods and a regular echinoid;(2)a low-energy,soft substrate habitat dominated by infaunal bivalves and echinoids.The high stress association is dominated by only two species and recorded from a high-energy shoal environment during a regression phase.A detailed study of macrobenthos and cephalopods provides a good paleoecological understanding of Cenomanian-Turonian succession in the Wadi Umm-Khayshar section.
文摘Geothermal exploration and development in North Africa have advanced significantly,driven by the region's rich geothermal resources and rising energy demand.The countries of Mauritania,Morocco,Algeria,Tunisia,Libya,and Egypt are located near tectonic plate boundaries(African and Eurasian plates),giving them substantial geothermal potential.Various exploration activities,including geological surveys and geophysical studies,have been conducted to assess geothermal reservoirs and identify suitable development sites.This article reviews the progress made in geothermal exploration across the region,highlighting the key activities undertaken to evaluate geothermal resources.It also explores how government policies have played a critical role either in fostering or in freezing geothermal development.The different conducted assessments such as analyzing geological structures,hydrothermal systems,and subsurface temperatures lead to identify suitable sites for geothermal development and improve the understanding of subsurface conditions and ongoing projects.Today,some countries in North Africa are positioning themselves to become important players in the global geothermal energy landscape,and with continued investment and concerted efforts,the region has the potential to emerge as a prominent player in the global geothermal energy landscape.
文摘Seyitgazi and Han districts,located in the south of Eskişehir in Central Anatolia,in western Türkiye,host interesting landforms,such as steep slopes,mesas and butte structures,fault-guided slopes,valleys,fairy chimneys,castle koppies,pillars,weathered rock blocks,perched rocks,cavernous weathering features,grooves,and gnammas,formed on tuffs in semi-arid to semi-humid climatic conditions,as well as geoarchaeological remains belonging to various civilisations,primarily the Phrygians(including rock-cut tombs and settlements,fortresses,rock churches,façades,altars,and niches).This study aims at identifying these remarkable landforms that host cultural heritage and revealing the geoheritage value and geotourism potential of the region.The data obtained from the fieldwork were evaluated using the methodology proposed by Pereira and Pereira in 2010,and 26 geomorphosites were selected from 61 potential sites using this method.The analysis results revealed that although the region hosts numerous geomorphosites with high scientific,cultural,aesthetic,and ecological value,the overall levels of protection and touristic use of these landforms are generally low.Indeed,the area,which has the potential to be an important tourism region in the future,faces problems such as infrastructure deficiencies,transportation difficulties,lack of promotion,weaknesses in accommodation services,and destruction of geoheritage.These results highlight the importance of implementing sustainable geotourism strategies that are compatible with the region’s unique geoheritage.In this respect,this study is among the first to comprehensively inventory and assess the geomorphosites of Mountainous Phrygia,contributing to regional geoconservation and sustainable tourism development.
基金Funded by the Spanish Government and FEDER funds(AEI/FEDER,UE)under grant PID2021-124502OB-C42(PRESECREL)the predoctoral program“Concepción Arenal del Programa de Personal Investigador en formación Predoctoral”funded by Universidad de Cantabria and Cantabria’s Government(BOC 18-10-2021).
文摘Predictive maintenance often involves imbalanced multivariate time series datasets with scarce failure events,posing challenges for model training due to the high dimensionality of the data and the need for domain-specific preprocessing,which frequently leads to the development of large and complex models.Inspired by the success of Large Language Models(LLMs),transformer-based foundation models have been developed for time series(TSFM).These models have been proven to reconstruct time series in a zero-shot manner,being able to capture different patterns that effectively characterize time series.This paper proposes the use of TSFM to generate embeddings of the input data space,making them more interpretable for machine learning models.To evaluate the effectiveness of our approach,we trained three classical machine learning algorithms and one neural network using the embeddings generated by the TSFM called Moment for predicting the remaining useful life of aircraft engines.We test the models trained with both the full training dataset and only 10%of the training samples.Our results show that training simple models,such as support vector regressors or neural networks,with embeddings generated by Moment not only accelerates the training process but also enhances performance in few-shot learning scenarios,where data is scarce.This suggests a promising alternative to complex deep learning architectures,particularly in industrial contexts with limited labeled data.
文摘This study evaluates the impact of heavy metals(zinc,copper and cadmium)on the development and metabolic responses of the maize(Zea mays)variety“Torro Plus”.Seeds were cultivated on MS medium enriched with progressively higher concentrations of heavy metals(50,100 and 150μM),and plants were analyzed after 21 days.The results show a significant reduction in morphological parameters,notably an 87.28%decrease in the fresh weight of aerial parts and a 69.93%decrease in the fresh weight of roots under 150μM of Cd.Chlorophyll a,b and total content also decreased drastically,reaching a maximum reduction of 74.31%under Cd(150μM).In contrast,secondary metabolites such as proline and flavonoids increased,with a maximum proline accumulation of 0.71 mg/g under Cu(150μM)and a flavonoid concentration reaching 176.33 mg/g under Cu(100μM).These results show mechanisms of adaptation to stress,notably the accumulation of flavonoids and proline,while highlighting the increased toxicity of cadmium at high doses.These data are promising for applications in phytoremediation and sustainable agriculture.This study provides important data on the physiological and biochemical responses of plants to heavy metals and opens up prospects for phytoremediation applications.
基金financially supported by the Ministry of Higher Education and Scientific Research of Tunisia.
文摘Oasis soils in Tunisia are characterized by low soil organic carbon(SOC)stocks,primarily due to their coarse texture and intensive irrigation practices.In the Gataaya Oasis,soils receive 3.000 to 4.000 L/m^(2) annually through submersion irrigation,leading to a rapid decline in SOC stocks.Despite their sandy texture,which promotes good water infiltration,these soils are enriched with clay,dissolved materials,and fertilizers in deeper horizons.This study aimed to assess SOC content in the Gataaya Oasis soils,investigate the transport of labile carbon in drainage water,and clarify the destiny of this transported carbon.Soil samples were collected systematically at three depths(0–10,10–20,and 20–30 cm),focusing on the top 30 cm depth,which is most affected by amendments.Two sampling points(P1 and P2)were selected,i.e.,P1 profile near the trunk of date palms(with manure input)and P2 profile between two adjacent date palms(without manure input).Water samples were collected from drainage systems within the oasis(W1,W2,and W3)and outside the oasis(W4).A laboratory experiment simulating manure application and irrigation was conducted to complement field observations.Physical-chemical analyses revealed a significant decrease in SOC stocks with soil depths.In P1 profile,SOC stocks declined from 17.71 t/hm^(2) at the 0–10 cm depth to 7.80 t/hm^(2) at the 20–30 cm depth.In P2 profile,SOC stocks were lower,decreasing from 6.73 t/hm^(2) at the 0–10 cm depth to 3.57 t/hm^(2) at the 20–30 cm depth.Labile carbon content in drainage water increased outside the oasis,with chemical oxygen demand(COD)values rising from 73 mg/L in W1 water sample to 290 mg/L in W4 water sample,indicating cumulative leaching effects from surrounding oases.The laboratory experiment confirmed field observations,showing a decline in soil organic matter(SOM)content from 3.27%to 2.62%after 12 irrigations,highlighting the vulnerability of SOC stocks to intensive irrigation.This study underscores the low SOC stocks in the Gataaya Oasis soils and their rapid depletion under successive irrigations.The findings provide insights into the dynamics of labile carbon transport and its contribution to regional carbon cycling,offering valuable information for sustainable soil management and ecological protection in arid ecosystems.
文摘African traditional medicine is characterized by its rich ethnobotanical heritage,diverse healing practices,and the integration of different culture influences.Similarly,traditional Chinese medicine(TCM)is deeply rooted in ancient philosophies,emphasizing balance,holistic diagnostics,and herbal formulations.Despite their geographical distance,both systems share historical and cultural parallels,particularly in their therapeutic principles,use of natural remedies,and holistic approaches to health.Combining these two medical traditions would offer a comprehensive perspective on healing,particularly through herbal medicine,diagnostic methods,and variations in preparation techniques and applications.As an example,Tetraena gaetula is a perennial plant endemic to the arid and semi-arid regions of Morocco,widely used in local medicine to treat diabetes,dermatological conditions,and liver,kidney,and stomach ailments,as well as in veterinary care.The unique properties of Tetraena gaetula could enhance research on multi-faceted approaches of Chinese medicine including herbal methodologies and local applications,contributing to the development of innovative medicines or therapies that integrate the strengths of both traditions.This paper explores potential strategies for integrating African traditional medicine and TCM,highlighting both the opportunities-such as the potential for new medicine discoveries,expanded treatment options,and cross-cultural knowledge exchange-and the challenges,including differences in regulatory frameworks,scientific validation,and the preservation of traditional knowledge.
文摘This study investigates the physical properties of the rare earth XFes(X=Sm,Dy,or Nd)materials.Our analysis encompasses these compounds'structural,electronic,thermodynamic,and optical characteristics using density functional theory(DFT)as implemented in the Wien2k software package.The GGA+SOC+U method was employed to determine the exchange-correlation potential.Our results show that the XFes materials exhibit metallic behavior and exhibit ferromagnetic(FM)phases.Notably,our optical analysis reveals a strong absorption response in the UV region,with characteristic absorption curves and peak intensities varying across the different materials.We also investigated the thermodynamic properties of the materials,finding that the entropy increases exponentially with temperature as the materials transition from a ground state to a more disordered and amorphous state.Our thermodynamic results show that the Debye temperature decreases for all three materials,with DyFes exhibiting the highest Debye temperature at 0 K(307 K),followed by NdFes(298 K),and then SmFes(288 K).This indicates that each material has a unique thermal energy barrier to overcome before vibrations occur.As the temperature increases,the Debye temperature decreases,reflecting a decrease in the thermal energy required to induce vibrations.The differences in Debye temperature values between the three materials may suggest differences in their lattice structures or phonon properties,highlighting the importance of understanding these thermal properties for developing new materials and technologies.
文摘This research study focuses on predicting ferrofluids’viscosity using machine learning models,artificial neural networks(ANNs),and random forests(RFs)incorporating key parameters;ferrofluid type,concentration of magnetic nanoparticles,temperature,and magnetic field intensity as inputs.A comprehensive database of 333 datasets sourced from various literatures was utilized for training and validating models.The ANN model demonstrated high accuracy,with root mean square error(RMSE)values below 0.033 and mean absolute percentage error(MAPE)not exceeding 3.01%,while the RF model achieved similar accuracy with RMSE under 0.052 and MAPE below 4.82%.Maximum deviations observed were 9.14%for ANN and 16.48%for RF,confirming that both models accurately learned the underlying patterns without overestimating viscosity.Additionally,the ANN model successfully captured intricate physical relationships between input parameters and viscosity when it was used to predict viscosity for random input data,confirming its ability to generalize beyond the training dataset.The RF model,however,showed limitations in extrapolating beyond the range of the training data.This research study demonstrates machine learning models’effectiveness in capturing intricate relationships governing the viscosity of ferrofluid for different types,paving the way for an improved understanding of ferrofluid’s viscosity behavior.
文摘The aim of this research is to assess the energy potential of cow dung and corn cob inputs,with a view to estimating their biogas potential.The inputs were characterized in the microbiology laboratory of the National Control Office Quality in Matoto,Conakry.The experiment to produce methane from cow dung and maize cob was carried out at the Applied Research in Natural Sciences Laboratory of the University of Kindia(UK)using the following equipment:Three digesters were each connected to an air chamber(gasometer)by means of flexible pipes 8 mm in diameter,connected by clamps,liquid adhesives,valves and Teflon.This research focused on determining the quantity of biogas contained in each type of substrate(cow dung,maize cob and their mixture).Three experiments on the methanization of these inputs were carried out,with anaerobic digestion lasting 27 days,in a temperature range of 27℃ to 31℃(mesophilic range).The results were as follows:maize cob 28.4 L,cow dung 22.6 L and codigestion 38.7 L.These results compared with similar studies revealed a coincidence.
基金supported through computational resources of HPC-MARWAN(www.marwan.ma/hpc)provided by CNRST,Rabat,Morocco。
文摘A classification of multipartite entanglement is introduced for pure and mixed states.The classification is based on the distribution of entanglement between the qubits of a given system,with a mathematical framework used to characterize fully entangled states.Then we use current machine learning and deep learning techniques to automatically classify a random state of two,three,and four qubits without the need to compute the amount of the different types of entanglement in each run;rather this is done only in the learning process.The technique shows high,near-perfect,accuracy in the case of pure states.As expected,this accuracy drops,more or less,when dealing with mixed states and when increasing the number of parties involved.
文摘The global reheating observed in these last years is followed with a change of rainfalls bunches at the global and regional area.The floods frequency increasing,dangerously impacts the socio-economic activities of several countries throughout the world.Indeed,for Niger as a country located in West Africa where the majority of the population existence depends on the agricultural and pastoral activities,this change of rainfalls bunches may have unwanted consequences.The aim of this work is to analyze the evolution and trend of rainfall in Niger during the period 2008-2024 compared to the period 1971-2000 characterized by episodes of drought.To achieve the objective of this work,annual data of rainfalls and the number of rainy days from four meteorological stations representative of the four major climatic zones of Niger are used.These are the station of Agadez(in Sahelian zone),the station of Tahoua(in mid Sahelian and Saharan zone),the station of Niamey(in Sahelian zone)and the station of Gaya(in mid Sahelian and Sudden zone).Thus,the standardized index of Lamb(1982)and the least squares method are respectively used to analyze the variability of the interannual rainfalls and their tendency.The results obtained show a significant improvement in rainfall in the four climatic zones compared to the period from 1971 to 2000,and especially in the Nigerien Sahara where 88.2%of the years were wet.The latitudinal gradient South-North of the rainfalls has known an upgrading going from 1 mm/km during the period of 1971-2000 to 1.26 mm/km during the period of 2008-2024.Our results also show that this improvement in rainfall is linked to heavy rainfall events which are the cause of floods observed mainly during wet years(2010,2012,2013,2017,2019 and 2024).Finally,the results show that,excepting the Sahel-Niger,the other climatic zones are experiencing an increasing trend in rainfall.Therefore,in the face of current climate change,West African countries must mobilize to put in place a strategy to mitigate the consequences of heavy rainfall.
文摘Since it first appeared in 2022,the phenomenon referred to as Colony Collapse Disorder(CCD)has affected several regions of Morocco to varying degrees.In order to assess the possible impact of pesticides on the appearance of this syndrome,we conducted a study aimed at evaluating the impact of pesticide use on the emergence of this syndrome through a year-long survey involving 160 beekeepers in the Beni Mellal–Khenifra Region(BKR)who also experienced an unprecedented desertion of hives during the same period.The majority of surveyed beekeepers practice mixed(45%)or migratory beekeeping(42%)and provide supplementary feeding(83.75%)to support their bees.Nearly 37.5%of the hives are located near crops treated with pesticides,exposing the bees to these chemicals.The results showed that the majority of beekeepers reported a cessation of queen laying(74.38%),high mortality rates among worker bees(81.25%),drones(65.63%),and queens(61.88%).Abnormal behaviors such as immobility with trembling(42.50%),reduced flights(47.50%),and disoriented navigation(28.75%)were also observed.Correlation analyses indicate that proximity to treated crops significantly increases the risk of queen laying cessation(Odds Ratio 6.0)and a reduction in waggle dances(Odds Ratio 2.41).Extended foraging flights show a borderline statistical significance(Odds Ratio 2.33),suggesting a disruption of natural food sources.These results highlight the potential impact of pesticides on colony health and bee behavior,pointing out the need to adapt beekeeping practices and implement protective measures against pesticides.
