BACKGROUND Childhood obesity is a growing global concern with far-reaching health implications.This study focuses on evaluating the knowledge and practices of physicians in Morocco regarding the link between maternal ...BACKGROUND Childhood obesity is a growing global concern with far-reaching health implications.This study focuses on evaluating the knowledge and practices of physicians in Morocco regarding the link between maternal obesity and childhood obesity.Despite the increasing prevalence of childhood obesity worldwide,this issue remains inadequately addressed in the Moroccan context.AIM To assess the awareness and practices of physicians in Morocco concerning the connection between maternal obesity and childhood obesity.METHODS The research encompasses a comprehensive survey of practicing physicians,revealing significant gaps in awareness and practices related to maternal obesity.RESULTS Notably,a significant portion of doctors do not provide adequate guidance to overweight pregnant women,highlighting the urgency for targeted educational programs.CONCLUSION In conclusion,this research illuminates critical areas for improvement in tackling childhood obesity in Morocco.By addressing these gaps,fostering awareness,and enhancing medical practices,the healthcare system can contribute significantly to preventing childhood obesity and improving the overall health of future generations.展开更多
Dallol Maouri is one of the fossil valleys on the left bank of the Niger River. Its watershed drains water from valleys in the Tahoua and Dosso regions of Niger. The watercourse is not continuous and has areas of surf...Dallol Maouri is one of the fossil valleys on the left bank of the Niger River. Its watershed drains water from valleys in the Tahoua and Dosso regions of Niger. The watercourse is not continuous and has areas of surface water accumulation (ponds) and areas of spreading and infiltration. The surface water potential in this area is limited, with most of the ponds having a temporary to the semi-permanent regime. Groundwater resources are, therefore, the main sources of withdrawal for human food, agriculture, and livestock. Climate change through the variation in rainfall, the often-anarchic multiplication of catchment works (wells and boreholes) and agricultural activities can have impacts on the qualitative and quantitative evolution of surface and groundwater. The objective of this study is to characterize the surface and underground water of the upper dallol Maouri through the physicochemical parameters of the water and the use of the isotopes of the water molecule (<sup>18</sup>O, <sup>2</sup>H and <sup>3</sup>H). A total of 53 water samples were analyzed at the laboratory of the Regional Directorate of Hydraulics and Sanitation of Tillabéri (Niger) for chemical parameters and 73 samples were analyzed at the Radio Analysis and Environment Laboratory (LRAE) of the National School of Engineers of Sfax (ENIS) of Tunis for isotopy. The water of the ponds is characterized by three types of facies: calcium bicarbonate, calcium and magnesium bicarbonate, and calcium nitrate chloride. The groundwater is 75% of the chloride-nitrate-calcium facies and the CT3/CT2 groundwater is calcium and magnesium bicarbonate. The results of the stable isotopes made it possible to highlight the presence of four distinct water groups: ponds characterized by highly evaporated water, the sheets of Continental Terminal 1 and 2 (CT1 and CT2) with an isotopic cachet of old water, the water table consisting of a two-layer system in the southwestern part of the area. The water is not very mineralized (40 μS to 600 μS) and is slightly acidic (pH = 6.4). The analysis of the radioactive isotope (<sup>3</sup>H) content of the water from the water table has made it possible to identify the areas of recharge of the water table. These results also highlight: the presence of an upward drainage zone, and the contribution of lowland ponds to the recharge of alluvial aquifers ranging from 24% to 84%. No structure in this zone reaches the Continental Intercalaire and the Continental Hamadien, the depth of which is estimated at an average of 600 m. The relationship between the <sup>18</sup>O and <sup>3</sup>H contents of groundwater water shows two types of water with tritium contents higher than 2 TU for alluvial aquifers and tritium contents lower than 2 TU for groundwater (CT3). The analysis of the radioactive isotope (<sup>3</sup>H) contents of the groundwater has made it possible to identify recent recharges at the level of the alluvial aquifers and in the outcrop zone of CT3. There is no hydraulic continuity between the plateau ponds and groundwater.展开更多
The hydrological models and simpli?ed methods of Saint-venant equations are used extensively in hydrological modeling, in particular for the simulation of the ?ood routing. These models require speci?c and extensive d...The hydrological models and simpli?ed methods of Saint-venant equations are used extensively in hydrological modeling, in particular for the simulation of the ?ood routing. These models require speci?c and extensive data that usually makes the study of ?ood propagation an arduous practice. We present in this work a new model, based on a transfer function, this function is a function of parametric probability density, having a physical meaning with respect to the propagation of a hydrological signal. The inversion of the model is carried out by an optimization technique called Genetic Algorithm. It consists of evolving a population of parameters based primarily on genetic recombination operators and natural selection to?nd the minimum of an objective function that measures the distance between observed and simulated data. The precision of the simulations of the proposed model is compared with the response of the Hayami model and the applicability of the model is tested on a real case, the N'Fis basin river, located in the High Atlas Occidental, which presents elements that appear favorable to the study of the propagation. The results obtained are very satisfactory and the simulation of the proposed model is very close to the response of the Hayami model.展开更多
Niamey, the capital of Niger, has experienced continuous demographic growth (+4%), accompanied by rapid urban expansion that is insufficiently controlled. This growth, combined with the effects of climate change as we...Niamey, the capital of Niger, has experienced continuous demographic growth (+4%), accompanied by rapid urban expansion that is insufficiently controlled. This growth, combined with the effects of climate change as well as a drastic change in land use (urbanization of cultivated fields, deforestation of plateaus and erosion of slopes) disrupts the water cycle, thus leading to the superposition of three types of floods: 1) rain floods (monsoon period);2) river floods (Niger river);and 3) flooding caused by rising water table. In several neighbourhoods, the water table is now out in a sustainable manner and degrades already fragile sanitary conditions. This study aims to clarify the functioning of aquifers in the city of Niamey due to the combination of geological, geophysical and hydrogeological data. Hydrogeological investigations make it possible to identify, in areas flooded by the water table, a shallow aquifer with low capacitance (effective porosity of a few %) and low permeability (2 × 10<sup>-6</sup> to 1 × 10<sup>-4</sup> m/s), overlying at a level shallow clay (~10 m) and lying on the Precambrian base (schists, granites). This configuration limits flows and has led to the appearance of permanent pools created by the water table in the valley thalweg in and around the city. Thus, in Niamey, an increase of up to twenty to forty meters was observed between 1961 and 2021 with seasonal piezometric fluctuations of a pluri-metric order following the rainy season. Beyond the health impacts, this trajectory negatively impacts land and locally causes degradation or displacement of traffic axes. Containing the level of the water table appears to be essential in the long term for sustainable sanitation in the city of Niamey.展开更多
The biofilm formation on equipment surfaces in dairy manufacturing is a major concern for industry and consumers alike, which may affect the safety and quality of dairy products. In order to identify the bio-contamina...The biofilm formation on equipment surfaces in dairy manufacturing is a major concern for industry and consumers alike, which may affect the safety and quality of dairy products. In order to identify the bio-contamination risk of materials commonly used in dairy manufacturing,</span><span style="font-family:""> </span><span style="font-family:Verdana;">adhesion of </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Staphylococcus aureus</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> on glass coated by two kinds of UHT milk (whole milk and skimmed milk) was investigated. It is known that adhesion is mainly governed by surface physicochemical properties, for that,</span><span style="font-family:""> </span><span style="font-family:Verdana;">the effect of milk components on physicochemical properties of glass and bacterial surfaces were exanimated through contact angle measurements. MATLAB software was used to evaluate the ability of </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">S.</span></i><i><span style="font-family:""> </span></i><i><span style="font-family:Verdana;">aureus</span></i><i><span style="font-family:Verdana;"></i></span></i><i><span style="font-family:""> </span></i><span style="font-family:Verdana;">adhesion on glass.</span><span style="font-family:""> </span><span style="font-family:Verdana;">The hydrophobic quantitative and electron acceptor characteristics of the glass appear to increase with the presence of fat in milk, while its electron donor property</span><span style="font-family:""> </span><span style="font-family:Verdana;">decreases with this component. The percentage of occupied surface of untreated glass was more important than in treated surfaces for 50% of the strains studied.</span><span style="font-family:""> </span><span style="font-family:Verdana;">As well, the percentage of occupied surface by bacterial strains in untreated glass by skimmed milk is generally more important compared to the whole milk. Therefore, the risk of bio-contamination of untreated glass is more favorable for bacteria cultured in skimmed milk compared to these in whole milk but the bio-contamination risk on covered glass by milk is not milk dependent and is strain dependent.展开更多
The purpose of this article is to show the role and influence of fluid injection, porosity on two-phase flows in porous media for the purpose of improving and increasing recovery efficiency assisted by oil. An experim...The purpose of this article is to show the role and influence of fluid injection, porosity on two-phase flows in porous media for the purpose of improving and increasing recovery efficiency assisted by oil. An experimental study was carried out in porous media, it is a plexiglass cylinder filled with sands saturated with crude oil. Pressure drop and data processing for two-phase flow are measured and processed using a differential pressure sensor connected to an acquisition computer. It thus makes it possible to determine the pressure difference between the inlet and the outlet of the porous medium over time. In this experiment, the flow rates at the inlet and the outlet of the porous medium were measured as a function of time using a flow rate and a pump. To describe these flows we will use Darcy’s model.展开更多
The surface energy characteristics of uncoated (clean) and coated stainless steel with UHT milk at various contact time (5 min, 30 min, 1 hours, 3 hours, 6 hours, 24 hours) were determined using contact angle measurem...The surface energy characteristics of uncoated (clean) and coated stainless steel with UHT milk at various contact time (5 min, 30 min, 1 hours, 3 hours, 6 hours, 24 hours) were determined using contact angle measurement. Whatever the contact time, the clean stainless steel coupons became more hydrophobic and more electron acceptor when they are coated by milk. Inversely, the electron donor character seems to decreasing in this condition. The calculated surface energy component of coated stainless steel was found to vary with contact time. Its hydrophobicity and its electron acceptor were minimal after 3 hours of contact, but its electron donor was minimal after 1 hours of contact. Adhesion experiments of Staphylococcus aureus were carried out on uncoated and coated stainless steels at various contact times. For all contact times, the adhesion results show that milk reduce S. aureus adhesion, and the level of this reduction depend on contact time. This reduction was lower and higher after 1 hours, 5 min and 30 min of contact respectively.展开更多
Pepino mosaic virus (PepMV), monopartite RNA virus, 6,500 pb, belonging to Flexiviridae and Potexvirus group, is highly infectious and easily transmissible. Its economic impact is major for the tomato producer's co...Pepino mosaic virus (PepMV), monopartite RNA virus, 6,500 pb, belonging to Flexiviridae and Potexvirus group, is highly infectious and easily transmissible. Its economic impact is major for the tomato producer's countries. Prevention, based on early virus detection is the only effective control measure. Monoclonal antibodies appeared to be very useful tool. The authors used for the production of monoclonal antibodies hybridomas technique, by fusing spleen cells of immunized BALB/c mice to PepMV and SP2/O cancerous cells. The aim of this work is to produce hybridomas producers of Mab that could be used for ELISA in Morocco. At the same time, these efforts will serve to decrease expenses of producers concerning phytosanitory control. We obtained 16 hybridomas lines producers of Mab specific for PepMV. They were tested for efficiencies in ELISA and two lines were retained for production of Mab on large scale (1B 11-G 10 and 5A l-G5). Isotyping of these two lines showed that they are belonging to IgG 1 class and easily purified by affinity chromatography in agarose column by protein A. The conjugation of these two antibodies to alkaline phosphatase has been verified by DAS-ELISA. These antibodies will enable to diagnose the disease from infected tomato plants, integrating several serological tests to control it and target the actions of struggles.展开更多
First report of Citrus tristeza virus (CTV, Closterovirus) in Morocco datesback to 1961 in collections of citrus varieties. An exhaustive survey of citrus in the north of the country in 2009 revealed that CTV was sp...First report of Citrus tristeza virus (CTV, Closterovirus) in Morocco datesback to 1961 in collections of citrus varieties. An exhaustive survey of citrus in the north of the country in 2009 revealed that CTV was spread all over the citrus production area. We attempted to evaluate the relative contribution of different aphid species in the spread of CTV disease in a Citrus reticulata orchard at the Loukkous region during 2 years (2012 and 2013). The overall CTV incidence estimated in the experimental site increased from 17.8% in 2012 to 31.15% in 2013. The most abundant aphid species colonising clementine trees was Aphis spiraecola and A. gossypii. Both aphid species reached their maximum peaks during the spring season. The rate of viruliferous aphids, estimated by real-time RT-PCR of single aphid, revealed that 35.4% of winged A. gossypii and 28.8% of winged A. spiraecola were viruliferous, confirming a high inoculum pressure in the area surrounding the experimental site. The aphid species Toxoptera citricida, which is able to transmit the aggressive isolates of CTV, was not found in the Loukkous region. The study of the spatial distribution of the CTV showed that in general, the disease was randomly distributed in the field. Overall, the results seem to indicate that A. spiraecola may be considered as the major aphid species contributing to CTV spread in our experimental conditions. The prevalence of mild strains in the region and the high level of aphid flight activity could explain the rapid evolution of CTV incidence in the experimental area.展开更多
Vibrational spectroscopy analysis of full-ripened fig fruits(Ficus carica L.)was acquired using Fourier-transformed infrared(FTIR)spectroscopy by attenuated total reflectance(ATR).The objective of this study was to in...Vibrational spectroscopy analysis of full-ripened fig fruits(Ficus carica L.)was acquired using Fourier-transformed infrared(FTIR)spectroscopy by attenuated total reflectance(ATR).The objective of this study was to investigate accurate discrimination of 25 fig cultivars using chemometric analysis of both ATR-FTIR fingerprinting and in-vitro antioxidant activity along with chromatic coordinates color.In-vitro antioxidant activity was assessed through three methods and displayed statistically significant differences across cultivars and between the fruit parts,with promising antioxidant potency.Infrared spectra were measured separately on both peels and pulp to better know which fruit part provides high discrimination throughput between cultivars.The results showed vibration intensities of five fingerprint regions displaying statically significant differences.The highest vibration intensity occurred in the region of 1175-940 cm^(-1)including the phenols fingerprint.Principal components analysis based on integrated intensities corresponding to fingerprint regions,revealed two main groups in pulp samples,while five groups in peels samples.The pulp extracts of’Nabout’showed a typical vibration in 3000-2800 cm^(-1)and 1775-1725 cm^(-1)regions and,therefore was classified as single subset in cultivars scatterplot.This cultivar had a lightcolored fig and exhibited the highest antioxidant potency for all essays particularly in peel extracts.The biochemical assessment and FTIR fingerprinting data were involved in PCA analysis,and that displayed some dissimilarities in the classification patterns,given the fact that antioxidant activities and chromaticity together could not totally explain the classification based on FTIR fingerprinting between peel and pulp.Application of FTIR-ATR spectroscopy to discriminate fig cultivars seems to be a rapid,accurate and cost-effective alternative to laborious measurement techniques,in fig quality screening and preselection,such as chromatography analysis.This study suggests the use of fig peels for a high-level discrimination while using ATR-FTIR spectroscopy,since it provides high-throughput screening framework.展开更多
Heavy floods occur frequently in the Senegal River Basin, causing catastrophic flooding downstream the river rating station of Bakel. Anticipating the occurrence of such phenomena is the only way to reduce the resulti...Heavy floods occur frequently in the Senegal River Basin, causing catastrophic flooding downstream the river rating station of Bakel. Anticipating the occurrence of such phenomena is the only way to reduce the resulting damages. Flood forecasting is a necessity. Flood forecasting plays also an important role in the implementation of flood management scenarios and in the protection of hydro electric structures. Many methods are applied. The most complete are based on the conservation laws of physics governing the free surface flow. These methods need a complete description of the geometry of the river and their implementation requires also huge investments. In practice the river basin can be considered as a system of inputs-outputs related by a transfer function. In this paper the authors first used a multiple linear regression model with constant parameters estimated by the ordinary least square method to simulate the propagation of the floods in the upstream part of the Senegal river basin. The authors then apply statistical and graphical criteria of goodness-of-fit to test the suitability of this model. Three procedures of parameters updating have then been added to this linear model: the Kalman filter method, the recursive least square method, and the stochastic gradient method The criteria of goodness-of-fit used above have shown that the stochastic gradient method, although more rudimentary, represents better the flood propagation in the head basin of the Senegal river upstream Bakel. This result is particularly interesting because data influenced by Manantali Dam are used.展开更多
Physico-chemical methods of improved oil recovery make it possible to increase oil production in deposits by injecting surfactants acting on various physical parameters. Oleic acid has an effect on the viscosity of th...Physico-chemical methods of improved oil recovery make it possible to increase oil production in deposits by injecting surfactants acting on various physical parameters. Oleic acid has an effect on the viscosity of the displacement fluid and the flow rate. Therefore, increasing the viscosity of the displacement fluid plays an essential role in improving the improved oil recovery. The physicochemical properties at the interface between petroleum and water are modified by oleic acid, lowering the viscosity of petroleum and increasing the viscosity of water, which facilitated the mobility of petroleum in the porous medium.展开更多
This paper deals with discontinuous dual reciprocity boundary element method for solving an inverse source problem.The aim of this work is to determine the source term in elliptic equations for nonhomogenous anisotrop...This paper deals with discontinuous dual reciprocity boundary element method for solving an inverse source problem.The aim of this work is to determine the source term in elliptic equations for nonhomogenous anisotropic media,where some additional boundary measurements are required.An equivalent formulation to the primary inverse problem is established based on the minimization of a functional cost,where a regularization term is employed to eliminate the oscillations of the noisy data.Moreover,an efficient algorithm is presented and tested for some numerical examples.展开更多
文摘BACKGROUND Childhood obesity is a growing global concern with far-reaching health implications.This study focuses on evaluating the knowledge and practices of physicians in Morocco regarding the link between maternal obesity and childhood obesity.Despite the increasing prevalence of childhood obesity worldwide,this issue remains inadequately addressed in the Moroccan context.AIM To assess the awareness and practices of physicians in Morocco concerning the connection between maternal obesity and childhood obesity.METHODS The research encompasses a comprehensive survey of practicing physicians,revealing significant gaps in awareness and practices related to maternal obesity.RESULTS Notably,a significant portion of doctors do not provide adequate guidance to overweight pregnant women,highlighting the urgency for targeted educational programs.CONCLUSION In conclusion,this research illuminates critical areas for improvement in tackling childhood obesity in Morocco.By addressing these gaps,fostering awareness,and enhancing medical practices,the healthcare system can contribute significantly to preventing childhood obesity and improving the overall health of future generations.
文摘Dallol Maouri is one of the fossil valleys on the left bank of the Niger River. Its watershed drains water from valleys in the Tahoua and Dosso regions of Niger. The watercourse is not continuous and has areas of surface water accumulation (ponds) and areas of spreading and infiltration. The surface water potential in this area is limited, with most of the ponds having a temporary to the semi-permanent regime. Groundwater resources are, therefore, the main sources of withdrawal for human food, agriculture, and livestock. Climate change through the variation in rainfall, the often-anarchic multiplication of catchment works (wells and boreholes) and agricultural activities can have impacts on the qualitative and quantitative evolution of surface and groundwater. The objective of this study is to characterize the surface and underground water of the upper dallol Maouri through the physicochemical parameters of the water and the use of the isotopes of the water molecule (<sup>18</sup>O, <sup>2</sup>H and <sup>3</sup>H). A total of 53 water samples were analyzed at the laboratory of the Regional Directorate of Hydraulics and Sanitation of Tillabéri (Niger) for chemical parameters and 73 samples were analyzed at the Radio Analysis and Environment Laboratory (LRAE) of the National School of Engineers of Sfax (ENIS) of Tunis for isotopy. The water of the ponds is characterized by three types of facies: calcium bicarbonate, calcium and magnesium bicarbonate, and calcium nitrate chloride. The groundwater is 75% of the chloride-nitrate-calcium facies and the CT3/CT2 groundwater is calcium and magnesium bicarbonate. The results of the stable isotopes made it possible to highlight the presence of four distinct water groups: ponds characterized by highly evaporated water, the sheets of Continental Terminal 1 and 2 (CT1 and CT2) with an isotopic cachet of old water, the water table consisting of a two-layer system in the southwestern part of the area. The water is not very mineralized (40 μS to 600 μS) and is slightly acidic (pH = 6.4). The analysis of the radioactive isotope (<sup>3</sup>H) content of the water from the water table has made it possible to identify the areas of recharge of the water table. These results also highlight: the presence of an upward drainage zone, and the contribution of lowland ponds to the recharge of alluvial aquifers ranging from 24% to 84%. No structure in this zone reaches the Continental Intercalaire and the Continental Hamadien, the depth of which is estimated at an average of 600 m. The relationship between the <sup>18</sup>O and <sup>3</sup>H contents of groundwater water shows two types of water with tritium contents higher than 2 TU for alluvial aquifers and tritium contents lower than 2 TU for groundwater (CT3). The analysis of the radioactive isotope (<sup>3</sup>H) contents of the groundwater has made it possible to identify recent recharges at the level of the alluvial aquifers and in the outcrop zone of CT3. There is no hydraulic continuity between the plateau ponds and groundwater.
文摘The hydrological models and simpli?ed methods of Saint-venant equations are used extensively in hydrological modeling, in particular for the simulation of the ?ood routing. These models require speci?c and extensive data that usually makes the study of ?ood propagation an arduous practice. We present in this work a new model, based on a transfer function, this function is a function of parametric probability density, having a physical meaning with respect to the propagation of a hydrological signal. The inversion of the model is carried out by an optimization technique called Genetic Algorithm. It consists of evolving a population of parameters based primarily on genetic recombination operators and natural selection to?nd the minimum of an objective function that measures the distance between observed and simulated data. The precision of the simulations of the proposed model is compared with the response of the Hayami model and the applicability of the model is tested on a real case, the N'Fis basin river, located in the High Atlas Occidental, which presents elements that appear favorable to the study of the propagation. The results obtained are very satisfactory and the simulation of the proposed model is very close to the response of the Hayami model.
文摘Niamey, the capital of Niger, has experienced continuous demographic growth (+4%), accompanied by rapid urban expansion that is insufficiently controlled. This growth, combined with the effects of climate change as well as a drastic change in land use (urbanization of cultivated fields, deforestation of plateaus and erosion of slopes) disrupts the water cycle, thus leading to the superposition of three types of floods: 1) rain floods (monsoon period);2) river floods (Niger river);and 3) flooding caused by rising water table. In several neighbourhoods, the water table is now out in a sustainable manner and degrades already fragile sanitary conditions. This study aims to clarify the functioning of aquifers in the city of Niamey due to the combination of geological, geophysical and hydrogeological data. Hydrogeological investigations make it possible to identify, in areas flooded by the water table, a shallow aquifer with low capacitance (effective porosity of a few %) and low permeability (2 × 10<sup>-6</sup> to 1 × 10<sup>-4</sup> m/s), overlying at a level shallow clay (~10 m) and lying on the Precambrian base (schists, granites). This configuration limits flows and has led to the appearance of permanent pools created by the water table in the valley thalweg in and around the city. Thus, in Niamey, an increase of up to twenty to forty meters was observed between 1961 and 2021 with seasonal piezometric fluctuations of a pluri-metric order following the rainy season. Beyond the health impacts, this trajectory negatively impacts land and locally causes degradation or displacement of traffic axes. Containing the level of the water table appears to be essential in the long term for sustainable sanitation in the city of Niamey.
文摘The biofilm formation on equipment surfaces in dairy manufacturing is a major concern for industry and consumers alike, which may affect the safety and quality of dairy products. In order to identify the bio-contamination risk of materials commonly used in dairy manufacturing,</span><span style="font-family:""> </span><span style="font-family:Verdana;">adhesion of </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Staphylococcus aureus</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> on glass coated by two kinds of UHT milk (whole milk and skimmed milk) was investigated. It is known that adhesion is mainly governed by surface physicochemical properties, for that,</span><span style="font-family:""> </span><span style="font-family:Verdana;">the effect of milk components on physicochemical properties of glass and bacterial surfaces were exanimated through contact angle measurements. MATLAB software was used to evaluate the ability of </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">S.</span></i><i><span style="font-family:""> </span></i><i><span style="font-family:Verdana;">aureus</span></i><i><span style="font-family:Verdana;"></i></span></i><i><span style="font-family:""> </span></i><span style="font-family:Verdana;">adhesion on glass.</span><span style="font-family:""> </span><span style="font-family:Verdana;">The hydrophobic quantitative and electron acceptor characteristics of the glass appear to increase with the presence of fat in milk, while its electron donor property</span><span style="font-family:""> </span><span style="font-family:Verdana;">decreases with this component. The percentage of occupied surface of untreated glass was more important than in treated surfaces for 50% of the strains studied.</span><span style="font-family:""> </span><span style="font-family:Verdana;">As well, the percentage of occupied surface by bacterial strains in untreated glass by skimmed milk is generally more important compared to the whole milk. Therefore, the risk of bio-contamination of untreated glass is more favorable for bacteria cultured in skimmed milk compared to these in whole milk but the bio-contamination risk on covered glass by milk is not milk dependent and is strain dependent.
文摘The purpose of this article is to show the role and influence of fluid injection, porosity on two-phase flows in porous media for the purpose of improving and increasing recovery efficiency assisted by oil. An experimental study was carried out in porous media, it is a plexiglass cylinder filled with sands saturated with crude oil. Pressure drop and data processing for two-phase flow are measured and processed using a differential pressure sensor connected to an acquisition computer. It thus makes it possible to determine the pressure difference between the inlet and the outlet of the porous medium over time. In this experiment, the flow rates at the inlet and the outlet of the porous medium were measured as a function of time using a flow rate and a pump. To describe these flows we will use Darcy’s model.
文摘The surface energy characteristics of uncoated (clean) and coated stainless steel with UHT milk at various contact time (5 min, 30 min, 1 hours, 3 hours, 6 hours, 24 hours) were determined using contact angle measurement. Whatever the contact time, the clean stainless steel coupons became more hydrophobic and more electron acceptor when they are coated by milk. Inversely, the electron donor character seems to decreasing in this condition. The calculated surface energy component of coated stainless steel was found to vary with contact time. Its hydrophobicity and its electron acceptor were minimal after 3 hours of contact, but its electron donor was minimal after 1 hours of contact. Adhesion experiments of Staphylococcus aureus were carried out on uncoated and coated stainless steels at various contact times. For all contact times, the adhesion results show that milk reduce S. aureus adhesion, and the level of this reduction depend on contact time. This reduction was lower and higher after 1 hours, 5 min and 30 min of contact respectively.
文摘Pepino mosaic virus (PepMV), monopartite RNA virus, 6,500 pb, belonging to Flexiviridae and Potexvirus group, is highly infectious and easily transmissible. Its economic impact is major for the tomato producer's countries. Prevention, based on early virus detection is the only effective control measure. Monoclonal antibodies appeared to be very useful tool. The authors used for the production of monoclonal antibodies hybridomas technique, by fusing spleen cells of immunized BALB/c mice to PepMV and SP2/O cancerous cells. The aim of this work is to produce hybridomas producers of Mab that could be used for ELISA in Morocco. At the same time, these efforts will serve to decrease expenses of producers concerning phytosanitory control. We obtained 16 hybridomas lines producers of Mab specific for PepMV. They were tested for efficiencies in ELISA and two lines were retained for production of Mab on large scale (1B 11-G 10 and 5A l-G5). Isotyping of these two lines showed that they are belonging to IgG 1 class and easily purified by affinity chromatography in agarose column by protein A. The conjugation of these two antibodies to alkaline phosphatase has been verified by DAS-ELISA. These antibodies will enable to diagnose the disease from infected tomato plants, integrating several serological tests to control it and target the actions of struggles.
文摘First report of Citrus tristeza virus (CTV, Closterovirus) in Morocco datesback to 1961 in collections of citrus varieties. An exhaustive survey of citrus in the north of the country in 2009 revealed that CTV was spread all over the citrus production area. We attempted to evaluate the relative contribution of different aphid species in the spread of CTV disease in a Citrus reticulata orchard at the Loukkous region during 2 years (2012 and 2013). The overall CTV incidence estimated in the experimental site increased from 17.8% in 2012 to 31.15% in 2013. The most abundant aphid species colonising clementine trees was Aphis spiraecola and A. gossypii. Both aphid species reached their maximum peaks during the spring season. The rate of viruliferous aphids, estimated by real-time RT-PCR of single aphid, revealed that 35.4% of winged A. gossypii and 28.8% of winged A. spiraecola were viruliferous, confirming a high inoculum pressure in the area surrounding the experimental site. The aphid species Toxoptera citricida, which is able to transmit the aggressive isolates of CTV, was not found in the Loukkous region. The study of the spatial distribution of the CTV showed that in general, the disease was randomly distributed in the field. Overall, the results seem to indicate that A. spiraecola may be considered as the major aphid species contributing to CTV spread in our experimental conditions. The prevalence of mild strains in the region and the high level of aphid flight activity could explain the rapid evolution of CTV incidence in the experimental area.
文摘Vibrational spectroscopy analysis of full-ripened fig fruits(Ficus carica L.)was acquired using Fourier-transformed infrared(FTIR)spectroscopy by attenuated total reflectance(ATR).The objective of this study was to investigate accurate discrimination of 25 fig cultivars using chemometric analysis of both ATR-FTIR fingerprinting and in-vitro antioxidant activity along with chromatic coordinates color.In-vitro antioxidant activity was assessed through three methods and displayed statistically significant differences across cultivars and between the fruit parts,with promising antioxidant potency.Infrared spectra were measured separately on both peels and pulp to better know which fruit part provides high discrimination throughput between cultivars.The results showed vibration intensities of five fingerprint regions displaying statically significant differences.The highest vibration intensity occurred in the region of 1175-940 cm^(-1)including the phenols fingerprint.Principal components analysis based on integrated intensities corresponding to fingerprint regions,revealed two main groups in pulp samples,while five groups in peels samples.The pulp extracts of’Nabout’showed a typical vibration in 3000-2800 cm^(-1)and 1775-1725 cm^(-1)regions and,therefore was classified as single subset in cultivars scatterplot.This cultivar had a lightcolored fig and exhibited the highest antioxidant potency for all essays particularly in peel extracts.The biochemical assessment and FTIR fingerprinting data were involved in PCA analysis,and that displayed some dissimilarities in the classification patterns,given the fact that antioxidant activities and chromaticity together could not totally explain the classification based on FTIR fingerprinting between peel and pulp.Application of FTIR-ATR spectroscopy to discriminate fig cultivars seems to be a rapid,accurate and cost-effective alternative to laborious measurement techniques,in fig quality screening and preselection,such as chromatography analysis.This study suggests the use of fig peels for a high-level discrimination while using ATR-FTIR spectroscopy,since it provides high-throughput screening framework.
文摘Heavy floods occur frequently in the Senegal River Basin, causing catastrophic flooding downstream the river rating station of Bakel. Anticipating the occurrence of such phenomena is the only way to reduce the resulting damages. Flood forecasting is a necessity. Flood forecasting plays also an important role in the implementation of flood management scenarios and in the protection of hydro electric structures. Many methods are applied. The most complete are based on the conservation laws of physics governing the free surface flow. These methods need a complete description of the geometry of the river and their implementation requires also huge investments. In practice the river basin can be considered as a system of inputs-outputs related by a transfer function. In this paper the authors first used a multiple linear regression model with constant parameters estimated by the ordinary least square method to simulate the propagation of the floods in the upstream part of the Senegal river basin. The authors then apply statistical and graphical criteria of goodness-of-fit to test the suitability of this model. Three procedures of parameters updating have then been added to this linear model: the Kalman filter method, the recursive least square method, and the stochastic gradient method The criteria of goodness-of-fit used above have shown that the stochastic gradient method, although more rudimentary, represents better the flood propagation in the head basin of the Senegal river upstream Bakel. This result is particularly interesting because data influenced by Manantali Dam are used.
文摘Physico-chemical methods of improved oil recovery make it possible to increase oil production in deposits by injecting surfactants acting on various physical parameters. Oleic acid has an effect on the viscosity of the displacement fluid and the flow rate. Therefore, increasing the viscosity of the displacement fluid plays an essential role in improving the improved oil recovery. The physicochemical properties at the interface between petroleum and water are modified by oleic acid, lowering the viscosity of petroleum and increasing the viscosity of water, which facilitated the mobility of petroleum in the porous medium.
文摘This paper deals with discontinuous dual reciprocity boundary element method for solving an inverse source problem.The aim of this work is to determine the source term in elliptic equations for nonhomogenous anisotropic media,where some additional boundary measurements are required.An equivalent formulation to the primary inverse problem is established based on the minimization of a functional cost,where a regularization term is employed to eliminate the oscillations of the noisy data.Moreover,an efficient algorithm is presented and tested for some numerical examples.