This article focuses on the experimental and numerical study of an industrial prototype furnace intended for the production of ceramics in order to improve the energy efficiency and therefore optimize the fuel consump...This article focuses on the experimental and numerical study of an industrial prototype furnace intended for the production of ceramics in order to improve the energy efficiency and therefore optimize the fuel consumption and the corresponding carbon dioxide emissions.In order to understand the thermal behavior from which stems the energy efficiency of the experimental prototype,we establish in this work,a simplified modeling allowing to establish a mathematical model describing the thermal behavior of the furnace.The model is able to accurately predict the spatial and temporal distribution of the temperature at each point of the furnace to control the firing of the refractory product so that the final product is of good quality in terms of resistance and hardness.In addition,the power consumed by the prototype must be optimized in order to reduce energy and environmental consumption.In particular,this efficient technology has allowed us to save 83% of energy used in the traditional furnace and to reduce 87.36% of the relative carbon dioxide emission.The simulation of the mathematical model made it possible to compare the numerical results with the experimental measurements obtained by the prototype as well as to validate the model and to adjust the heat transfer parameters.展开更多
Objective:To assess the applicability degree of the international guidelines by Moroccan radiotherapists,in order to improve the management of cervical cancer(CC),since CC is the second most common cancer for women in...Objective:To assess the applicability degree of the international guidelines by Moroccan radiotherapists,in order to improve the management of cervical cancer(CC),since CC is the second most common cancer for women in Morocco.Methods:This cross-sectional study was carried out using a questionnaire sent online to Moroccan radiotherapists.The questionnaire covered participants'characteristics,initial assessment and treatment preparation,techniques and indications for radiotherapy and brachytherapy,dose and indications,as well as on the protocol adopted in the intermediate stages and the location of adjuvant treatments and assessments'follow-up.Results:74 radiotherapists out of 300 have responded to the survey.Only 27.0%of practitioners reported discussing patient records systematically in a multidisciplinary consultation meeting(MCM).For the initial assessment,77.0%requested pelvic magnetic resonance imaging(MRI).It is significantly less requested in regional oncology centers(ROCs)than in university hospital centers(UHCs)or the private sector(P<0.001).Furthermore,Clinicians in ROCs do not have access to new techniques of radiotherapy.In 83.8%of cases,the most prescribed radiotherapy protocols were 45–46 Gy in 1.8–2 Gy per fraction.Three-dimensional gynaecological brachytherapy high-throughput dose guided by dosimetric scanner was available in 75.5%of structures while interstitial gynaecological brachytherapy was only available in 23%of centers.The two most prescribed dose protocols were 47 Gy and 37 Gy in 74.4%and 21.6%of cases,respectively.Finally,monitoring during the first two years was based mainly on pelvic MRI(82.2%)while PET/CT was recommended by only less than 10%.Conclusions:The findings obtained show that our radiotherapists generally comply with international guidelines for the cervical cancer management.However,they should still enhance their practices for the first staging evaluation,the use of systematic MCMs,the doses and treatment techniques used,and the follow-up evaluation.展开更多
A study to evaluate the physico-chemical and bacteriological quality of groundwater was carried out in the commune of Mbankomo(Centre-Cameroon)at 4 wells and 4 springs during the period from March to August.The physic...A study to evaluate the physico-chemical and bacteriological quality of groundwater was carried out in the commune of Mbankomo(Centre-Cameroon)at 4 wells and 4 springs during the period from March to August.The physico-chemical parameters were measured by the standard method.Indicator bacteria of fecal contamination,namely HAB(Heterotrophic Aerobic Bacteria),total and faecal coliforms(Escherichia coli),and faecal streptococci were isolated by the surface spreading technique on PCA(Plate Count Agar),Endo and BEA(Bile Esculin Azide)agar respectively,and sulphite-reducing clostridia by the incorporation method on Tryptone Sulfite Cycloserine(TSC)agar.From a physico-chemical point of view,the groundwater in Mbamkomo is characterized by an average temperature(24.24±0.24°C);it is polluted with organic matter,acid and poorly mineralized.It was noted from a bacteriological point of view that these waters have a high and varied bacterial load with an average value of 100.8 × 10^(5) CFU/100 mL for coliforms,16.3 × 10^(5) CFU/100 mL for fecal streptococci,5.6 × 10^(5) CFU/100 mL for Escherichia coli and 4.8 ×10^(²)CFU/100 mL for Clostridium perfringens.These concentrations are all higher than the WHO(World Health Organization)standards which are set at 0 CFU/100 mL for coliforms,fecal streptococci and Clostridium perfringens and indicate fecal pollution of these waters.Escherichia coli cell densities were significantly correlated with dissolved oxygen in the water(r=0.510;p<0.05).The degradation of the quality of these waters is favored by their proximity to pollution sources,poor maintenance and poor protection of the wells.These waters,without any treatment,are not recommended for human consumption according to the standards of the WHO.展开更多
Nanofluids are a potential alternative to significantly improving the performance of heat transfer applications. In this work, a numerical analysis to examine the eff ect of dispersing copper(Cu), copper oxide(CuO), a...Nanofluids are a potential alternative to significantly improving the performance of heat transfer applications. In this work, a numerical analysis to examine the eff ect of dispersing copper(Cu), copper oxide(CuO), and aluminum(Al2O3) nanoparticles in pure water on the performance of a flat plate solar collector(FPSC) and a numerical model was proposed. The influence of the nanofluid type on the thermal efficiency was critically investigated and discussed. The eff ect of the mass flow rate on the performance was also analyzed and discussed. Based on correlations of the thermophysical properties of nanofluids, a sensitivity analysis was used to analyze the impact of the nanoparticles on the base fluid. The results indicate that the performance of the FPSC with Cu/water nanofluid was better than that of FPSCs using CuO/water or Al2O3/water nanofluids. When the mass flow rate of the nanofluids was 8.0 L/min, the efficiency of the FPSC was much greater than those at the flow rates of 5.0 L/min and 2.0 L/min. Mean enhancements in thermal efficiency of 4.44%, 4.27%, and 4.21% were observed when 2.0 L/min was applied using Cu/water, Cu O/water, and Al2O3/water nanofluids, respectively. Improvements in thermal efficiency of 2.76%, 2.53%, and 2.47% occurred when 8.0 L/min was applied.展开更多
The aim of this review was to examine the theoretical,preclinical and clinical bases of the combination radiotherapy immunotherapy in the management of non-small cell lung cancer(NSCLC).Preclinical studies have shown ...The aim of this review was to examine the theoretical,preclinical and clinical bases of the combination radiotherapy immunotherapy in the management of non-small cell lung cancer(NSCLC).Preclinical studies have shown that in addition to its well-established tumoricidal effects,radiotherapy can activate the host immune system and modify the tumor microenvironment.Immunotherapy is currently part of the therapeutic arsenal of the NSCLC given its capacity to restore the host's immune system's ability to recognize and destroy tumor cells.The combination of radiotherapy and immunotherapy seems to be synergistic,particularly with inhibitors of immune checkpoints.This association has become standard in the metastatic stages and especially in consolidation after radiochemotherapy in the locally advanced,unresectable and stable stages.Several questions remain unanswered including the optimal sequence of this combination,the type of radiotherapy(hypo-fractionated or normofractionated),the association of several immunotherapies and the cross-toxicity of the combination.The association of radiotherapy and immunotherapy is a promising treatment.展开更多
基金funded by a grant from Ministry of Industry of Morocco.
文摘This article focuses on the experimental and numerical study of an industrial prototype furnace intended for the production of ceramics in order to improve the energy efficiency and therefore optimize the fuel consumption and the corresponding carbon dioxide emissions.In order to understand the thermal behavior from which stems the energy efficiency of the experimental prototype,we establish in this work,a simplified modeling allowing to establish a mathematical model describing the thermal behavior of the furnace.The model is able to accurately predict the spatial and temporal distribution of the temperature at each point of the furnace to control the firing of the refractory product so that the final product is of good quality in terms of resistance and hardness.In addition,the power consumed by the prototype must be optimized in order to reduce energy and environmental consumption.In particular,this efficient technology has allowed us to save 83% of energy used in the traditional furnace and to reduce 87.36% of the relative carbon dioxide emission.The simulation of the mathematical model made it possible to compare the numerical results with the experimental measurements obtained by the prototype as well as to validate the model and to adjust the heat transfer parameters.
文摘Objective:To assess the applicability degree of the international guidelines by Moroccan radiotherapists,in order to improve the management of cervical cancer(CC),since CC is the second most common cancer for women in Morocco.Methods:This cross-sectional study was carried out using a questionnaire sent online to Moroccan radiotherapists.The questionnaire covered participants'characteristics,initial assessment and treatment preparation,techniques and indications for radiotherapy and brachytherapy,dose and indications,as well as on the protocol adopted in the intermediate stages and the location of adjuvant treatments and assessments'follow-up.Results:74 radiotherapists out of 300 have responded to the survey.Only 27.0%of practitioners reported discussing patient records systematically in a multidisciplinary consultation meeting(MCM).For the initial assessment,77.0%requested pelvic magnetic resonance imaging(MRI).It is significantly less requested in regional oncology centers(ROCs)than in university hospital centers(UHCs)or the private sector(P<0.001).Furthermore,Clinicians in ROCs do not have access to new techniques of radiotherapy.In 83.8%of cases,the most prescribed radiotherapy protocols were 45–46 Gy in 1.8–2 Gy per fraction.Three-dimensional gynaecological brachytherapy high-throughput dose guided by dosimetric scanner was available in 75.5%of structures while interstitial gynaecological brachytherapy was only available in 23%of centers.The two most prescribed dose protocols were 47 Gy and 37 Gy in 74.4%and 21.6%of cases,respectively.Finally,monitoring during the first two years was based mainly on pelvic MRI(82.2%)while PET/CT was recommended by only less than 10%.Conclusions:The findings obtained show that our radiotherapists generally comply with international guidelines for the cervical cancer management.However,they should still enhance their practices for the first staging evaluation,the use of systematic MCMs,the doses and treatment techniques used,and the follow-up evaluation.
文摘A study to evaluate the physico-chemical and bacteriological quality of groundwater was carried out in the commune of Mbankomo(Centre-Cameroon)at 4 wells and 4 springs during the period from March to August.The physico-chemical parameters were measured by the standard method.Indicator bacteria of fecal contamination,namely HAB(Heterotrophic Aerobic Bacteria),total and faecal coliforms(Escherichia coli),and faecal streptococci were isolated by the surface spreading technique on PCA(Plate Count Agar),Endo and BEA(Bile Esculin Azide)agar respectively,and sulphite-reducing clostridia by the incorporation method on Tryptone Sulfite Cycloserine(TSC)agar.From a physico-chemical point of view,the groundwater in Mbamkomo is characterized by an average temperature(24.24±0.24°C);it is polluted with organic matter,acid and poorly mineralized.It was noted from a bacteriological point of view that these waters have a high and varied bacterial load with an average value of 100.8 × 10^(5) CFU/100 mL for coliforms,16.3 × 10^(5) CFU/100 mL for fecal streptococci,5.6 × 10^(5) CFU/100 mL for Escherichia coli and 4.8 ×10^(²)CFU/100 mL for Clostridium perfringens.These concentrations are all higher than the WHO(World Health Organization)standards which are set at 0 CFU/100 mL for coliforms,fecal streptococci and Clostridium perfringens and indicate fecal pollution of these waters.Escherichia coli cell densities were significantly correlated with dissolved oxygen in the water(r=0.510;p<0.05).The degradation of the quality of these waters is favored by their proximity to pollution sources,poor maintenance and poor protection of the wells.These waters,without any treatment,are not recommended for human consumption according to the standards of the WHO.
文摘Nanofluids are a potential alternative to significantly improving the performance of heat transfer applications. In this work, a numerical analysis to examine the eff ect of dispersing copper(Cu), copper oxide(CuO), and aluminum(Al2O3) nanoparticles in pure water on the performance of a flat plate solar collector(FPSC) and a numerical model was proposed. The influence of the nanofluid type on the thermal efficiency was critically investigated and discussed. The eff ect of the mass flow rate on the performance was also analyzed and discussed. Based on correlations of the thermophysical properties of nanofluids, a sensitivity analysis was used to analyze the impact of the nanoparticles on the base fluid. The results indicate that the performance of the FPSC with Cu/water nanofluid was better than that of FPSCs using CuO/water or Al2O3/water nanofluids. When the mass flow rate of the nanofluids was 8.0 L/min, the efficiency of the FPSC was much greater than those at the flow rates of 5.0 L/min and 2.0 L/min. Mean enhancements in thermal efficiency of 4.44%, 4.27%, and 4.21% were observed when 2.0 L/min was applied using Cu/water, Cu O/water, and Al2O3/water nanofluids, respectively. Improvements in thermal efficiency of 2.76%, 2.53%, and 2.47% occurred when 8.0 L/min was applied.
文摘The aim of this review was to examine the theoretical,preclinical and clinical bases of the combination radiotherapy immunotherapy in the management of non-small cell lung cancer(NSCLC).Preclinical studies have shown that in addition to its well-established tumoricidal effects,radiotherapy can activate the host immune system and modify the tumor microenvironment.Immunotherapy is currently part of the therapeutic arsenal of the NSCLC given its capacity to restore the host's immune system's ability to recognize and destroy tumor cells.The combination of radiotherapy and immunotherapy seems to be synergistic,particularly with inhibitors of immune checkpoints.This association has become standard in the metastatic stages and especially in consolidation after radiochemotherapy in the locally advanced,unresectable and stable stages.Several questions remain unanswered including the optimal sequence of this combination,the type of radiotherapy(hypo-fractionated or normofractionated),the association of several immunotherapies and the cross-toxicity of the combination.The association of radiotherapy and immunotherapy is a promising treatment.
