Human tumors tend to activate the immune system regulatory checkpoints as a means of escaping immunosurveillance. For instance, interaction between program death-1(PD-1) and program death-ligand 1(PD-L1) will lead the...Human tumors tend to activate the immune system regulatory checkpoints as a means of escaping immunosurveillance. For instance, interaction between program death-1(PD-1) and program death-ligand 1(PD-L1) will lead the activated T cell to a state of anergy. PD-L1 is upregulated on a wide range of cancer cells. Anti-PD-1 and anti-PD-L1 monoclonal antibodies(m Abs), called immune checkpoint inhibitors(ICIs), have consequently been designed to restore T cell activity. Accumulating data are in favor of an association between PD-L1 expression in tumors and response to treatment. A PD-L1 expression is present in 30% to 50% of digestive cancers. Multiple anti-PD-1(nivolumab, pembrolizumab) and anti-PD-L1 m Abs(MPDL3280A, Medi4736) are under evaluation in digestive cancers. Preliminary results in metastatic gastric cancer with pembrolizumab are highly promising and phase Ⅱ will start soon. In metastatic colorectal cancer(CRC), a phase Ⅲ trial of MPDL3280 A as maintenance therapy will shortly be initiated. Trials are also ongoing in metastatic CRC with high immune T cell infiltration(i.e., microsatellite instability). Major challenges are ahead in order to determine how, when and for which patients we should use these ICIs. New radiologic criteria to evaluate tumor response to ICIs are awaiting prospective validation. The optimal therapeutic sequence and association with cytotoxic chemotherapy needs to be established. Finally, biomarker identification will be crucial to selection ofpatients likely to benefit from ICIs.展开更多
AIM: To investigate the conformity of management practices of gastrointestinal hemorrhage in cirrhotic patients with relevant guidelines. METHODS: A questionnaire on the management of digestive bleeding was completed ...AIM: To investigate the conformity of management practices of gastrointestinal hemorrhage in cirrhotic patients with relevant guidelines. METHODS: A questionnaire on the management of digestive bleeding was completed for all consecutive cirrhotic patients admitted to 31 French hospitals. RESULTS: One hundred and twenty-six bleeding events were recorded. It was the first bleeding episode in 79 patients (63%), of whom 40 (51%) had a prior diagnosis of cirrhosis and 25 (32%) had previously undergone an endoscopy. The bleeding episode was a recurrence in 46 patients (37%). The median time between onset and admission was 4 h, but exceeded 12 h in 42% of cases. There was an agreement between centers forearly vasoactive drug administration (87% of cases), association with ligation (42%) more often than sclerosis (21%) at initial endoscopy, and antibiotic prophylaxis (64%). By contrast, prescription of beta-blockade alone or in combination (0 to 100%, P = 0.003) for secondary prophylaxis and lactulose (26% to 86%, P = 0.04), differed among centers. CONCLUSION: In French hospitals, management of bleeding related to portal hypertension in cirrhotic patients is generally in keeping with the consensus. Broad variability still remains concerning beta-blockade use for secondary prophylaxis. Screening for esophageal varices, the use of antibiotic prophylaxis and patients information need to be improved.展开更多
An experimental method for a single layer is extended to determine the elastic properties of nanostructured W/C u multilayers on a flexible substrate.The strain difference between the W/Cu-polyimide-W/Cu composite and...An experimental method for a single layer is extended to determine the elastic properties of nanostructured W/C u multilayers on a flexible substrate.The strain difference between the W/Cu-polyimide-W/Cu composite and the uncoated substrate,measured by dual digital image correlation,allows us to extract the effective Young's modulus of W/Cu multilayers(20 periods)equaling 216±13 GPa.Finite element method is then performed,which agrees well with the experiment and classical rule of mixture(ROM)theory demonstrating that the extension to multilayers is effective and reliable.The numerical analysis also interestingly shows that the strain difference is linearly related to the thickness ratio(W/Cu),periods and sublayer thickness,respectively.In contrast to ROM theory,this approach could potentially be used for the evaluation of properties and design of emerging/unknown functional multilayers,whether or not they are crystalline or amorphous.展开更多
AIM: To compare the incidence of spontaneous bacterial peritonitis in cirrhotic outpatients and inpatients undergoing therapeutic paracentesis METHODS: From January 1 to May 31, 2004, 1041 patients from 70 different h...AIM: To compare the incidence of spontaneous bacterial peritonitis in cirrhotic outpatients and inpatients undergoing therapeutic paracentesis METHODS: From January 1 to May 31, 2004, 1041 patients from 70 different hospitals underwent 2123 therapeutic abdominal paracentesis (AP) performed as a outpatient procedure in 355 and as inpatient procedure in 686 cases respectively. The following parameters were compared prospectively between outpatients and inpatients: spontaneous bacterial peritonitis (SBP) prevalence, age, gender, cause of cirrhosis, symptoms, score and grade according to Child-Pugh classification, cirrhosis complications, antibiotics treatment, serum creatinine, platelet count and ascitic protein concentration. RESULTS: SBP was observed in 91 patients. In the whole population the SBP prevalence was 8.7% (95%CI: 7.2-10.6) it was 11.7% (95%CI: 9.5-14.3) in inpatients and 3.1% (95%CI: 1.7-5.5) in outpatients (P < 0.00001). SBP prevalence was 8.3% (95%CI: 4.3-15.6) in symptomatic outpatients vs 1.2% (95%CI: 0.4-3.4) in asymptomatic outpatients (P < 0.002). Patients undergoing outpatient AP were significantly different from those undergoing inpatient AP; they were older (61.1 ± 11.1 years vs 59.4 ± 11.7 years; P = 0.028), cause of cirrhosis was less often alcohol (83 .7 vs 88.2%; P < 0.001), Child-Pugh score was lower (8.9 vs 10.1; P < 0.001) and more often B than C (63.7% vs 38%; P < 0.001). In addition, in outpatients the platelet count was higher (161 ± 93 Giga/L vs 143 ± 89 Giga/L; P = 0.003), serum total bilirubin concentration was lower (38.2 ± 60.7 μmol/L vs 96.3 ± 143.3 μmol/L; P < 0.0001), and ascitic protein concentration higher (17.9 ± 10.7 g/L vs 14.5 ± 10.9 g/L; P < 0.001) than in inpatients. CONCLUSION: In asymptomatic cirrhotic outpatients, the incidence of spontaneous bacterial peritonitis is low thus exploratory paracentesis could be avoided in these patients without significant risk.展开更多
Amyotrophic lateral sclerosis（ALS）, identified as a distinct clinical entity by Charcot since the end of the nineteenth century, is a devastating and fatal neurodegenerative disorder that affects motor neurons in th...Amyotrophic lateral sclerosis（ALS）, identified as a distinct clinical entity by Charcot since the end of the nineteenth century, is a devastating and fatal neurodegenerative disorder that affects motor neurons in the brain, brainstem and spinal cord. Survival of patients with ALS is associated with several factors such as clinical phenotype, age at onset, gender, early presence of respiratory failure, weight loss and treatment with Riluzole（the only disease-modifying drug approved for this disease）. Nowadays, there is still no curative treatment for ALS： palliative care and symptomatic treatment are therefore essential components in the management of these patients. Nevertheless, the scientific knowledge in the field of ALS motor neuron degeneration is growing, with the prospect of new treatments. Based on this physiopathological knowledge, several new therapeutic targets are being studied, involving various mechanisms such as excitotoxicity, neuroinflammation, mitochondrial dysfunction, oxidative stress, RNA metabolism and other attractive concepts. Moreover, it is also important to identify reliable biomarkers that will be essential components for future therapeutic development and study design in ALS. In this review, we present the main recent advances and promising therapeutics and biomarkers in the field of ALS.展开更多
Acute scrotal pain(AsP)requiring surgical exploration is common in the pediatric population,but little has been reported on this subject with regard to the adult population.The aim of this study was to investigate the...Acute scrotal pain(AsP)requiring surgical exploration is common in the pediatric population,but little has been reported on this subject with regard to the adult population.The aim of this study was to investigate the demographic and clinical characteristics and outcomes of scrotal explorations performed on adult patients.Patients over 21 years of age who underwent surgical exploration for ASP with suspected testicular torsion(TT)at 14 French hospitals between January 2005 and December 2019 were included in this study.The main outcome measures were demographic characteristics,pathology found during scrotal exploration,and perioperative outcomes.Logistic regression was used to perform univariate and multivariate analyses to identify predictors of TT.Data for 1329 men were analyzed.The median age was 30(interquartile range[IQR]:25-35;range:21-89)years.Regarding the clinical examination,867(65.2%)patients presented with an elevation of the testicle,613(46.1%)patients with scrotal edema or erythema,and 211(15.9%)patients with nausea or vomiting.Operative findings identified TT in only 684(51.5%)patients,epididymo-orchitis in 112(8.4%)patients,a tumor in 16(1.2%)patients,and no causes in 475(35.7%)patients.Orchiectomy for nonviable testes was required in 101(7.6%)patients.In multivariate analysis,an elevation of the testicle,erythema/swelling,and the presence of nausea/vomiting were found to be associated with the occurrence of TT.Testicular torsion is not exclusive to children and adolescents,so must be considered in males of any age with acute scrotal findings.However,one-third of scrotal explorations in adults did not lead to a diagnosis.展开更多
The soil potentials, facing to the crop fields, are commonly estimated through the calculation of their available water capacity based on the ETP or ETM estimation. The present work introduces the comparison between t...The soil potentials, facing to the crop fields, are commonly estimated through the calculation of their available water capacity based on the ETP or ETM estimation. The present work introduces the comparison between theoretical and real available water capacity profiles calculated down to 1.00 m depth. The evapotranspiration data are used to the calculation of ETP in an undrained grassland and ETM in two drained corn fields located in the French Atlantic marshlands. The studied soils have acquired specific properties in response to the reclaiming of the clay;dominant primary sediments began since the Middle Age and late drainage works. The theoretical and real available water capacity profiles are calculated from the ETP and ETM data and from the soil moisture profiles respectively, from June to October 2013. The theoretical and real profiles are confronted to the tensiometric pressure recording at 30, 60 and 90 cm. The tensiometric pressure behavior and associated premature disconnections of the tensiometric plugs are explained thanks to the soil structure-hydromechanical property relationships: i.e. from ductile state in depth to brittle state in surface. The vertical evolutions of the real profiles are explained facing to the plant growing, pluviometry and water nape levels. Their behavior and their shifts from the linear “theoretical” ETP or ETM profiles clearly show the advance of the desiccation front and consequently the kinetics of water consumption by plants. This simple method of calculation and comparison between the real and theoretical ETM or ETP profiles allows the quantitative discussion: 1) on the role of the soil microstructure behavior on the root growing and, 2) on the realism of the crop coefficient taken into account in the ETP or ETM estimation. In these coastal marsh fields, it also argues on the difficulty of management facing to the water and/or salt stresses.展开更多
Digital technologies are becoming present and essential in all sectors of our lives.In education,the intensive usage of digital learning devices contributes to generating a large amount of trace data from digital lear...Digital technologies are becoming present and essential in all sectors of our lives.In education,the intensive usage of digital learning devices contributes to generating a large amount of trace data from digital learning activities.Intelligent exploitation of these traces represents a valuable asset for both device producers(to improve the design of the devices)and consumers(learners and teachers).In this paper,we first share our vision for better exploitation by teachers,of traces from middle schoolers’digital activities generated by their use of tools and digital learning services during different classes.This vision is a part of the AT41 project funded by the French Ministry of Education.This exploitation has to meet the requirements of the different teachers.Conducting such a project is not an easy task,because it has to consider the following issues:①the lack of comprehensive and clear methodology to design and exploit these traces;①heterogeneity of teacher requirements that complicates their elicitation and analysis;①the diversity of trace sources.Secondly,we propose a requirement-driven architecture for Learning Analytics composed of a well-identified life cycle.This architecture is augmented by learner traces.It offers a repository storing both teacher requirements and traces to facilitate the Learning Analytics in generating relevant and valuable indicators.展开更多
This communication proposes to study some language processes, similar in literature and videogames： parapraxis and the choice of a pseudo. It will aim to show how the use of a word reveals the intimacy of the subject...This communication proposes to study some language processes, similar in literature and videogames： parapraxis and the choice of a pseudo. It will aim to show how the use of a word reveals the intimacy of the subject, just like the autobiographical novel, which gives information about the writer. We would therefore have the presages of a self-writing in the creation, naming and storytelling of the avatar of a videogame player. From the example of a young player of the MMORPG （Massively Multiplayer Online Role Playing Games） networking game Dofus, who we met in consultation, we will see how his avatar ＂Deadlop＂ comes from parapraxis and enables the narration of his emotional intimacy. The unconscious elements that led to the creation of the pseudo enabled him to tell his story and grasp some unexplained facets of himself.展开更多
Iron-containing SBA-15 catalysts have been prepared following different synthesis routes, direct synthesis by adjusting pH at 3 and 6 and with post synthesis procedure. Activity and stability of these materials were a...Iron-containing SBA-15 catalysts have been prepared following different synthesis routes, direct synthesis by adjusting pH at 3 and 6 and with post synthesis procedure. Activity and stability of these materials were assessed on the photo-Fenton degradation of phenolic aqueous solutions by H2O2 using near ultraviolet irradiation （254 nm） at room temperature and initial neutral pH. Their catalytic performance was mentioned in terms of phenol and TOC （total organic carbon） conversions. Several complementary techniques, including X-ray, nitrogen sorption isotherms, UV （Ultraviolet） visible, were used to evaluate the final structural and textural properties of calcined Fe-SBA 15 materials. These materials show a high activity and stability of iron species.展开更多
Microwave irradiation has been used to prepare AI, Fe-pillared clays from a natural Tunisian smcctitc from the E1 Hicha deposit （province of Gabes）. Chemical analysis, XRD spectra and surface properties evidenced th...Microwave irradiation has been used to prepare AI, Fe-pillared clays from a natural Tunisian smcctitc from the E1 Hicha deposit （province of Gabes）. Chemical analysis, XRD spectra and surface properties evidenced the success of pillaring process. The obtained solids present higher surthce area and pore volume than conventionally prepared A1-Fe pillared clays. The main advantages of the microwave methodology are the considerable reduction of the synthesis time and the consumption of water. The microwave-derived AI-Fe pillared clays have been tested tbr catalytic wet air oxidation （CWAO） of phenol in a stirred tank at 160℃ and 20 bar of pure oxygen pressure. These materials are efficient for CWAO of phenol and are highly stable despite the severe operating conditions （acidic media, high pressure, high temperature）. The catalyst deactivation was also significantly hindered when compared to conventionally prepared clays. A1-Fe pillared clays prepared by microwave methodology are promising as catalysts for CWAO industrial water treatment.展开更多
文摘Human tumors tend to activate the immune system regulatory checkpoints as a means of escaping immunosurveillance. For instance, interaction between program death-1(PD-1) and program death-ligand 1(PD-L1) will lead the activated T cell to a state of anergy. PD-L1 is upregulated on a wide range of cancer cells. Anti-PD-1 and anti-PD-L1 monoclonal antibodies(m Abs), called immune checkpoint inhibitors(ICIs), have consequently been designed to restore T cell activity. Accumulating data are in favor of an association between PD-L1 expression in tumors and response to treatment. A PD-L1 expression is present in 30% to 50% of digestive cancers. Multiple anti-PD-1(nivolumab, pembrolizumab) and anti-PD-L1 m Abs(MPDL3280A, Medi4736) are under evaluation in digestive cancers. Preliminary results in metastatic gastric cancer with pembrolizumab are highly promising and phase Ⅱ will start soon. In metastatic colorectal cancer(CRC), a phase Ⅲ trial of MPDL3280 A as maintenance therapy will shortly be initiated. Trials are also ongoing in metastatic CRC with high immune T cell infiltration(i.e., microsatellite instability). Major challenges are ahead in order to determine how, when and for which patients we should use these ICIs. New radiologic criteria to evaluate tumor response to ICIs are awaiting prospective validation. The optimal therapeutic sequence and association with cytotoxic chemotherapy needs to be established. Finally, biomarker identification will be crucial to selection ofpatients likely to benefit from ICIs.
基金Supported by grants from the French Society of Gastroenterology
文摘AIM: To investigate the conformity of management practices of gastrointestinal hemorrhage in cirrhotic patients with relevant guidelines. METHODS: A questionnaire on the management of digestive bleeding was completed for all consecutive cirrhotic patients admitted to 31 French hospitals. RESULTS: One hundred and twenty-six bleeding events were recorded. It was the first bleeding episode in 79 patients (63%), of whom 40 (51%) had a prior diagnosis of cirrhosis and 25 (32%) had previously undergone an endoscopy. The bleeding episode was a recurrence in 46 patients (37%). The median time between onset and admission was 4 h, but exceeded 12 h in 42% of cases. There was an agreement between centers forearly vasoactive drug administration (87% of cases), association with ligation (42%) more often than sclerosis (21%) at initial endoscopy, and antibiotic prophylaxis (64%). By contrast, prescription of beta-blockade alone or in combination (0 to 100%, P = 0.003) for secondary prophylaxis and lactulose (26% to 86%, P = 0.04), differed among centers. CONCLUSION: In French hospitals, management of bleeding related to portal hypertension in cirrhotic patients is generally in keeping with the consensus. Broad variability still remains concerning beta-blockade use for secondary prophylaxis. Screening for esophageal varices, the use of antibiotic prophylaxis and patients information need to be improved.
基金This research is financially supported by the National Natural Science Foundation of China(Grant 11802156)China Postdoctoral Science Foundation(Grant 2018M641331)French Government Program“Investissements d’Avenir”(Labex Interactifs,Grant ANR-11-LABX-0017-01).
文摘An experimental method for a single layer is extended to determine the elastic properties of nanostructured W/C u multilayers on a flexible substrate.The strain difference between the W/Cu-polyimide-W/Cu composite and the uncoated substrate,measured by dual digital image correlation,allows us to extract the effective Young's modulus of W/Cu multilayers(20 periods)equaling 216±13 GPa.Finite element method is then performed,which agrees well with the experiment and classical rule of mixture(ROM)theory demonstrating that the extension to multilayers is effective and reliable.The numerical analysis also interestingly shows that the strain difference is linearly related to the thickness ratio(W/Cu),periods and sublayer thickness,respectively.In contrast to ROM theory,this approach could potentially be used for the evaluation of properties and design of emerging/unknown functional multilayers,whether or not they are crystalline or amorphous.
文摘AIM: To compare the incidence of spontaneous bacterial peritonitis in cirrhotic outpatients and inpatients undergoing therapeutic paracentesis METHODS: From January 1 to May 31, 2004, 1041 patients from 70 different hospitals underwent 2123 therapeutic abdominal paracentesis (AP) performed as a outpatient procedure in 355 and as inpatient procedure in 686 cases respectively. The following parameters were compared prospectively between outpatients and inpatients: spontaneous bacterial peritonitis (SBP) prevalence, age, gender, cause of cirrhosis, symptoms, score and grade according to Child-Pugh classification, cirrhosis complications, antibiotics treatment, serum creatinine, platelet count and ascitic protein concentration. RESULTS: SBP was observed in 91 patients. In the whole population the SBP prevalence was 8.7% (95%CI: 7.2-10.6) it was 11.7% (95%CI: 9.5-14.3) in inpatients and 3.1% (95%CI: 1.7-5.5) in outpatients (P < 0.00001). SBP prevalence was 8.3% (95%CI: 4.3-15.6) in symptomatic outpatients vs 1.2% (95%CI: 0.4-3.4) in asymptomatic outpatients (P < 0.002). Patients undergoing outpatient AP were significantly different from those undergoing inpatient AP; they were older (61.1 ± 11.1 years vs 59.4 ± 11.7 years; P = 0.028), cause of cirrhosis was less often alcohol (83 .7 vs 88.2%; P < 0.001), Child-Pugh score was lower (8.9 vs 10.1; P < 0.001) and more often B than C (63.7% vs 38%; P < 0.001). In addition, in outpatients the platelet count was higher (161 ± 93 Giga/L vs 143 ± 89 Giga/L; P = 0.003), serum total bilirubin concentration was lower (38.2 ± 60.7 μmol/L vs 96.3 ± 143.3 μmol/L; P < 0.0001), and ascitic protein concentration higher (17.9 ± 10.7 g/L vs 14.5 ± 10.9 g/L; P < 0.001) than in inpatients. CONCLUSION: In asymptomatic cirrhotic outpatients, the incidence of spontaneous bacterial peritonitis is low thus exploratory paracentesis could be avoided in these patients without significant risk.
文摘Amyotrophic lateral sclerosis（ALS）, identified as a distinct clinical entity by Charcot since the end of the nineteenth century, is a devastating and fatal neurodegenerative disorder that affects motor neurons in the brain, brainstem and spinal cord. Survival of patients with ALS is associated with several factors such as clinical phenotype, age at onset, gender, early presence of respiratory failure, weight loss and treatment with Riluzole（the only disease-modifying drug approved for this disease）. Nowadays, there is still no curative treatment for ALS： palliative care and symptomatic treatment are therefore essential components in the management of these patients. Nevertheless, the scientific knowledge in the field of ALS motor neuron degeneration is growing, with the prospect of new treatments. Based on this physiopathological knowledge, several new therapeutic targets are being studied, involving various mechanisms such as excitotoxicity, neuroinflammation, mitochondrial dysfunction, oxidative stress, RNA metabolism and other attractive concepts. Moreover, it is also important to identify reliable biomarkers that will be essential components for future therapeutic development and study design in ALS. In this review, we present the main recent advances and promising therapeutics and biomarkers in the field of ALS.
文摘Acute scrotal pain(AsP)requiring surgical exploration is common in the pediatric population,but little has been reported on this subject with regard to the adult population.The aim of this study was to investigate the demographic and clinical characteristics and outcomes of scrotal explorations performed on adult patients.Patients over 21 years of age who underwent surgical exploration for ASP with suspected testicular torsion(TT)at 14 French hospitals between January 2005 and December 2019 were included in this study.The main outcome measures were demographic characteristics,pathology found during scrotal exploration,and perioperative outcomes.Logistic regression was used to perform univariate and multivariate analyses to identify predictors of TT.Data for 1329 men were analyzed.The median age was 30(interquartile range[IQR]:25-35;range:21-89)years.Regarding the clinical examination,867(65.2%)patients presented with an elevation of the testicle,613(46.1%)patients with scrotal edema or erythema,and 211(15.9%)patients with nausea or vomiting.Operative findings identified TT in only 684(51.5%)patients,epididymo-orchitis in 112(8.4%)patients,a tumor in 16(1.2%)patients,and no causes in 475(35.7%)patients.Orchiectomy for nonviable testes was required in 101(7.6%)patients.In multivariate analysis,an elevation of the testicle,erythema/swelling,and the presence of nausea/vomiting were found to be associated with the occurrence of TT.Testicular torsion is not exclusive to children and adolescents,so must be considered in males of any age with acute scrotal findings.However,one-third of scrotal explorations in adults did not lead to a diagnosis.
文摘The soil potentials, facing to the crop fields, are commonly estimated through the calculation of their available water capacity based on the ETP or ETM estimation. The present work introduces the comparison between theoretical and real available water capacity profiles calculated down to 1.00 m depth. The evapotranspiration data are used to the calculation of ETP in an undrained grassland and ETM in two drained corn fields located in the French Atlantic marshlands. The studied soils have acquired specific properties in response to the reclaiming of the clay;dominant primary sediments began since the Middle Age and late drainage works. The theoretical and real available water capacity profiles are calculated from the ETP and ETM data and from the soil moisture profiles respectively, from June to October 2013. The theoretical and real profiles are confronted to the tensiometric pressure recording at 30, 60 and 90 cm. The tensiometric pressure behavior and associated premature disconnections of the tensiometric plugs are explained thanks to the soil structure-hydromechanical property relationships: i.e. from ductile state in depth to brittle state in surface. The vertical evolutions of the real profiles are explained facing to the plant growing, pluviometry and water nape levels. Their behavior and their shifts from the linear “theoretical” ETP or ETM profiles clearly show the advance of the desiccation front and consequently the kinetics of water consumption by plants. This simple method of calculation and comparison between the real and theoretical ETM or ETP profiles allows the quantitative discussion: 1) on the role of the soil microstructure behavior on the root growing and, 2) on the realism of the crop coefficient taken into account in the ETP or ETM estimation. In these coastal marsh fields, it also argues on the difficulty of management facing to the water and/or salt stresses.
文摘Digital technologies are becoming present and essential in all sectors of our lives.In education,the intensive usage of digital learning devices contributes to generating a large amount of trace data from digital learning activities.Intelligent exploitation of these traces represents a valuable asset for both device producers(to improve the design of the devices)and consumers(learners and teachers).In this paper,we first share our vision for better exploitation by teachers,of traces from middle schoolers’digital activities generated by their use of tools and digital learning services during different classes.This vision is a part of the AT41 project funded by the French Ministry of Education.This exploitation has to meet the requirements of the different teachers.Conducting such a project is not an easy task,because it has to consider the following issues:①the lack of comprehensive and clear methodology to design and exploit these traces;①heterogeneity of teacher requirements that complicates their elicitation and analysis;①the diversity of trace sources.Secondly,we propose a requirement-driven architecture for Learning Analytics composed of a well-identified life cycle.This architecture is augmented by learner traces.It offers a repository storing both teacher requirements and traces to facilitate the Learning Analytics in generating relevant and valuable indicators.
文摘This communication proposes to study some language processes, similar in literature and videogames： parapraxis and the choice of a pseudo. It will aim to show how the use of a word reveals the intimacy of the subject, just like the autobiographical novel, which gives information about the writer. We would therefore have the presages of a self-writing in the creation, naming and storytelling of the avatar of a videogame player. From the example of a young player of the MMORPG （Massively Multiplayer Online Role Playing Games） networking game Dofus, who we met in consultation, we will see how his avatar ＂Deadlop＂ comes from parapraxis and enables the narration of his emotional intimacy. The unconscious elements that led to the creation of the pseudo enabled him to tell his story and grasp some unexplained facets of himself.
文摘Iron-containing SBA-15 catalysts have been prepared following different synthesis routes, direct synthesis by adjusting pH at 3 and 6 and with post synthesis procedure. Activity and stability of these materials were assessed on the photo-Fenton degradation of phenolic aqueous solutions by H2O2 using near ultraviolet irradiation （254 nm） at room temperature and initial neutral pH. Their catalytic performance was mentioned in terms of phenol and TOC （total organic carbon） conversions. Several complementary techniques, including X-ray, nitrogen sorption isotherms, UV （Ultraviolet） visible, were used to evaluate the final structural and textural properties of calcined Fe-SBA 15 materials. These materials show a high activity and stability of iron species.
文摘Microwave irradiation has been used to prepare AI, Fe-pillared clays from a natural Tunisian smcctitc from the E1 Hicha deposit （province of Gabes）. Chemical analysis, XRD spectra and surface properties evidenced the success of pillaring process. The obtained solids present higher surthce area and pore volume than conventionally prepared A1-Fe pillared clays. The main advantages of the microwave methodology are the considerable reduction of the synthesis time and the consumption of water. The microwave-derived AI-Fe pillared clays have been tested tbr catalytic wet air oxidation （CWAO） of phenol in a stirred tank at 160℃ and 20 bar of pure oxygen pressure. These materials are efficient for CWAO of phenol and are highly stable despite the severe operating conditions （acidic media, high pressure, high temperature）. The catalyst deactivation was also significantly hindered when compared to conventionally prepared clays. A1-Fe pillared clays prepared by microwave methodology are promising as catalysts for CWAO industrial water treatment.
