The Experts below are selected from a list of 191436 Experts worldwide ranked by ideXlab platform
Loic Barre - One of the best experts on this subject based on the ideXlab platform.
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a small angle neutron scattering study of the adsorbed asphaltene layer in water in hydrocarbon emulsions structural description related to stability
Langmuir, 2007Co-Authors: Jacques Jestin, Sebastien Simon, Lina Zupancic, Loic BarreAbstract:We have developed a Specific Protocol to study with SANS measurements, the structure of the interfacial film layer in water-in-oil emulsions stabilized by asphaltene. Using the contrast matching technique available for neutron scattering, we have access to both the composition and the quantity of interface. The results obtained give us a view of the asphaltene aggregates in the interfacial film, which are structured as a monolayer and show a direct correlation between the size of asphaltene aggregates in solution and the thickness of the film layer. The organization of the interface has been studied as a function of several parameters such as the quantity of resins, i.e., the size of aggregates, the pH of the aqueous phase, and the aging time of the emulsions and the consequences of these variations on the macroscopic stability of these emulsions. We show that the key parameter for the stability is the inter-asphaltene aggregate interaction inside the film layer. Changing the attractive/repulsive balance between the aggregates in the film at the microscopic scale, by changing the aggregate's size or the aggregate's ionization, has a direct incidence on the quantity of water recovered after centrifugation: the stronger the attraction between aggregates in the film, the more stable the emulsion is.
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a small angle neutron scattering study of the adsorbed asphaltene layer in water in hydrocarbon emulsions structural description related to stability
Langmuir, 2007Co-Authors: Jacques Jestin, Sebastien Simon, Lina Zupancic, Loic BarreAbstract:We have developed a Specific Protocol to study with SANS measurements, the structure of the interfacial film layer in water-in-oil emulsions stabilized by asphaltene. Using the contrast matching technique available for neutron scattering, we have access to both the composition and the quantity of interface. The results obtained give us a view of the asphaltene aggregates in the interfacial film, which are structured as a monolayer and show a direct correlation between the size of asphaltene aggregates in solution and the thickness of the film layer. The organization of the interface has been studied as a function of several parameters such as the quantity of resins, i.e., the size of aggregates, the pH of the aqueous phase, and the aging time of the emulsions and the consequences of these variations on the macroscopic stability of these emulsions. We show that the key parameter for the stability is the inter-asphaltene aggregate interaction inside the film layer. Changing the attractive/repulsive balance ...
Jacques Jestin - One of the best experts on this subject based on the ideXlab platform.
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a small angle neutron scattering study of the adsorbed asphaltene layer in water in hydrocarbon emulsions structural description related to stability
Langmuir, 2007Co-Authors: Jacques Jestin, Sebastien Simon, Lina Zupancic, Loic BarreAbstract:We have developed a Specific Protocol to study with SANS measurements, the structure of the interfacial film layer in water-in-oil emulsions stabilized by asphaltene. Using the contrast matching technique available for neutron scattering, we have access to both the composition and the quantity of interface. The results obtained give us a view of the asphaltene aggregates in the interfacial film, which are structured as a monolayer and show a direct correlation between the size of asphaltene aggregates in solution and the thickness of the film layer. The organization of the interface has been studied as a function of several parameters such as the quantity of resins, i.e., the size of aggregates, the pH of the aqueous phase, and the aging time of the emulsions and the consequences of these variations on the macroscopic stability of these emulsions. We show that the key parameter for the stability is the inter-asphaltene aggregate interaction inside the film layer. Changing the attractive/repulsive balance between the aggregates in the film at the microscopic scale, by changing the aggregate's size or the aggregate's ionization, has a direct incidence on the quantity of water recovered after centrifugation: the stronger the attraction between aggregates in the film, the more stable the emulsion is.
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a small angle neutron scattering study of the adsorbed asphaltene layer in water in hydrocarbon emulsions structural description related to stability
Langmuir, 2007Co-Authors: Jacques Jestin, Sebastien Simon, Lina Zupancic, Loic BarreAbstract:We have developed a Specific Protocol to study with SANS measurements, the structure of the interfacial film layer in water-in-oil emulsions stabilized by asphaltene. Using the contrast matching technique available for neutron scattering, we have access to both the composition and the quantity of interface. The results obtained give us a view of the asphaltene aggregates in the interfacial film, which are structured as a monolayer and show a direct correlation between the size of asphaltene aggregates in solution and the thickness of the film layer. The organization of the interface has been studied as a function of several parameters such as the quantity of resins, i.e., the size of aggregates, the pH of the aqueous phase, and the aging time of the emulsions and the consequences of these variations on the macroscopic stability of these emulsions. We show that the key parameter for the stability is the inter-asphaltene aggregate interaction inside the film layer. Changing the attractive/repulsive balance ...
Sebastien Simon - One of the best experts on this subject based on the ideXlab platform.
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a small angle neutron scattering study of the adsorbed asphaltene layer in water in hydrocarbon emulsions structural description related to stability
Langmuir, 2007Co-Authors: Jacques Jestin, Sebastien Simon, Lina Zupancic, Loic BarreAbstract:We have developed a Specific Protocol to study with SANS measurements, the structure of the interfacial film layer in water-in-oil emulsions stabilized by asphaltene. Using the contrast matching technique available for neutron scattering, we have access to both the composition and the quantity of interface. The results obtained give us a view of the asphaltene aggregates in the interfacial film, which are structured as a monolayer and show a direct correlation between the size of asphaltene aggregates in solution and the thickness of the film layer. The organization of the interface has been studied as a function of several parameters such as the quantity of resins, i.e., the size of aggregates, the pH of the aqueous phase, and the aging time of the emulsions and the consequences of these variations on the macroscopic stability of these emulsions. We show that the key parameter for the stability is the inter-asphaltene aggregate interaction inside the film layer. Changing the attractive/repulsive balance between the aggregates in the film at the microscopic scale, by changing the aggregate's size or the aggregate's ionization, has a direct incidence on the quantity of water recovered after centrifugation: the stronger the attraction between aggregates in the film, the more stable the emulsion is.
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a small angle neutron scattering study of the adsorbed asphaltene layer in water in hydrocarbon emulsions structural description related to stability
Langmuir, 2007Co-Authors: Jacques Jestin, Sebastien Simon, Lina Zupancic, Loic BarreAbstract:We have developed a Specific Protocol to study with SANS measurements, the structure of the interfacial film layer in water-in-oil emulsions stabilized by asphaltene. Using the contrast matching technique available for neutron scattering, we have access to both the composition and the quantity of interface. The results obtained give us a view of the asphaltene aggregates in the interfacial film, which are structured as a monolayer and show a direct correlation between the size of asphaltene aggregates in solution and the thickness of the film layer. The organization of the interface has been studied as a function of several parameters such as the quantity of resins, i.e., the size of aggregates, the pH of the aqueous phase, and the aging time of the emulsions and the consequences of these variations on the macroscopic stability of these emulsions. We show that the key parameter for the stability is the inter-asphaltene aggregate interaction inside the film layer. Changing the attractive/repulsive balance ...
Lina Zupancic - One of the best experts on this subject based on the ideXlab platform.
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a small angle neutron scattering study of the adsorbed asphaltene layer in water in hydrocarbon emulsions structural description related to stability
Langmuir, 2007Co-Authors: Jacques Jestin, Sebastien Simon, Lina Zupancic, Loic BarreAbstract:We have developed a Specific Protocol to study with SANS measurements, the structure of the interfacial film layer in water-in-oil emulsions stabilized by asphaltene. Using the contrast matching technique available for neutron scattering, we have access to both the composition and the quantity of interface. The results obtained give us a view of the asphaltene aggregates in the interfacial film, which are structured as a monolayer and show a direct correlation between the size of asphaltene aggregates in solution and the thickness of the film layer. The organization of the interface has been studied as a function of several parameters such as the quantity of resins, i.e., the size of aggregates, the pH of the aqueous phase, and the aging time of the emulsions and the consequences of these variations on the macroscopic stability of these emulsions. We show that the key parameter for the stability is the inter-asphaltene aggregate interaction inside the film layer. Changing the attractive/repulsive balance between the aggregates in the film at the microscopic scale, by changing the aggregate's size or the aggregate's ionization, has a direct incidence on the quantity of water recovered after centrifugation: the stronger the attraction between aggregates in the film, the more stable the emulsion is.
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a small angle neutron scattering study of the adsorbed asphaltene layer in water in hydrocarbon emulsions structural description related to stability
Langmuir, 2007Co-Authors: Jacques Jestin, Sebastien Simon, Lina Zupancic, Loic BarreAbstract:We have developed a Specific Protocol to study with SANS measurements, the structure of the interfacial film layer in water-in-oil emulsions stabilized by asphaltene. Using the contrast matching technique available for neutron scattering, we have access to both the composition and the quantity of interface. The results obtained give us a view of the asphaltene aggregates in the interfacial film, which are structured as a monolayer and show a direct correlation between the size of asphaltene aggregates in solution and the thickness of the film layer. The organization of the interface has been studied as a function of several parameters such as the quantity of resins, i.e., the size of aggregates, the pH of the aqueous phase, and the aging time of the emulsions and the consequences of these variations on the macroscopic stability of these emulsions. We show that the key parameter for the stability is the inter-asphaltene aggregate interaction inside the film layer. Changing the attractive/repulsive balance ...
The Spirit-pro Group - One of the best experts on this subject based on the ideXlab platform.
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Guidelines for inclusion of patient-reported outcomes in clinical trial Protocols: The SPIRIT-PRO Extension
'American Medical Association (AMA)', 2018Co-Authors: Calvert M, Kyte D, Mercieca-bebber R, Slade A, Mt King, The Spirit-pro Group, Aw Chan, Dg AltmanAbstract:Importance Patient-reported outcome (PRO) data from clinical trials can provide valuable evidence to inform shared decision making, labeling claims, clinical guidelines, and health policy; however, the PRO content of clinical trial Protocols is often suboptimal. The SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) statement was published in 2013 and aims to improve the completeness of trial Protocols by providing evidence-based recommendations for the minimum set of items to be addressed, but it does not provide PRO-Specific guidance. Objective To develop international, consensus-based, PRO-Specific Protocol guidance (the SPIRIT-PRO Extension). Design, Setting, and Participants The SPIRIT-PRO Extension was developed following the Enhancing Quality and Transparency of Health Research (EQUATOR) Network’s methodological framework for guideline development. This included (1) a systematic review of existing PRO-Specific Protocol guidance to generate a list of potential PRO-Specific Protocol items (published in 2014); (2) refinements to the list and removal of duplicate items by the International Society for Quality of Life Research (ISOQOL) Protocol Checklist Taskforce; (3) an international stakeholder survey of clinical trial research personnel, PRO methodologists, health economists, psychometricians, patient advocates, funders, industry representatives, journal editors, policy makers, ethicists, and researchers responsible for evidence synthesis (distributed by 38 international partner organizations in October 2016); (4) an international Delphi exercise (n = 137 invited; October 2016 to February 2017); and (5) consensus meeting (n = 30 invited; May 2017). Prior to voting, consensus meeting participants were informed of the results of the Delphi exercise and given data from structured reviews evaluating the PRO Protocol content of 3 defined samples of trial Protocols. Results The systematic review identified 162 PRO-Specific Protocol recommendations from 54 sources. The ISOQOL Taskforce (n = 21) reduced this to 56 items, which were considered by 138 international stakeholder survey participants and 99 Delphi panelists. The final wording of the SPIRIT-PRO Extension was agreed on at a consensus meeting (n = 29 participants) and reviewed by external group of experts during a consultation period. Eleven extensions and 5 elaborations to the SPIRIT 2013 checklist were recommended for inclusion in clinical trial Protocols in which PROs are a primary or key secondary outcome. Extension items focused on PRO-Specific issues relating to the trial rationale, objectives, eligibility criteria, concepts used to evaluate the intervention, time points for assessment, PRO instrument selection and measurement properties, data collection plan, translation to other languages, proxy completion, strategies to minimize missing data, and whether PRO data will be monitored during the study to inform clinical care. Conclusions and Relevance The SPIRIT-PRO guidelines provide recommendations for items that should be addressed and included in clinical trial Protocols in which PROs are a primary or key secondary outcome. Improved design of clinical trials including PROs could help ensure high-quality data that may inform patient-centered care
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Guidelines for Inclusion of Patient-Reported Outcomes in Clinical Trial Protocols: The SPIRIT-PRO Extension
'American Medical Association (AMA)', 2018Co-Authors: Calvert M, Kyte D, Mercieca-bebber R, Slade A, Chan A-w, Mt King, The Spirit-pro GroupAbstract:Importance: Patient-reported outcome (PRO) data from clinical trials can provide valuable evidence to inform shared-decision making, labelling claims, clinical guidelines, and health policy; however, the PRO content of clinical trial Protocols is often suboptimal. The SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) Statement was published in 2013 and aims to improve the completeness of trial Protocols by providing evidence-based recommendations for the minimum set of items to be addressed, but does not provide PRO-Specific guidance. Objective: To develop international, consensus-based, PRO-Specific Protocol guidance: the SPIRIT-PRO extension. Design, Setting, and Participants: The SPIRIT-PRO Extension was developed following the Enhancing QUAlity and Transparency Of health Research (EQUATOR) Network’s methodological framework for guideline development. This included: (i) a systematic review of existing PRO-Specific Protocol guidance to generate a list of candidate PRO-Specific Protocol items (published 2014); (ii) refinements to the list and removal of duplicate items by the International Society for Quality of Life Research (ISOQOL) Protocol Checklist Taskforce; (iii) an international stakeholder survey of: clinical trial research personnel, PRO methodologists, health economists, psychometricians, patient advocates, funders, industry representatives, journal editors, policy makers, ethicists and researchers responsible for evidence synthesis (distributed by 38 international partner organizations, October 2016); (iv) an international Delphi exercise (n=137 invited; October 2016 to February 2017)and consensus meeting (n=30 invited; May 2017). Prior to voting, consensus meeting participants were informed of the results of the Delphi exercise and given data from structured reviews evaluating the PRO Protocol content of three defined samples of trial Protocols. Results: The systematic review identified 162 PRO-Specific Protocol recommendations from 54 sources. The ISOQOL Taskforce (n=21) reduced this to 56 items, which were considered by 138 international stakeholders and 99 Delphi panelists. The final wording of the SPIRIT-PRO Extension was agreed at a consensus meeting (n=29 participants) and reviewed by external stakeholders during a consultation period. Eleven extensions and five elaborations to the SPIRIT 2013 checklist are recommended for inclusion in clinical trial Protocols where PROs are a primary or key secondary outcome. Extension items focused on PRO Specific issues relating to the: trial rationale, objectives, eligibility criteria, concepts used to evaluate the intervention, timepoints for assessment, PRO instrument selection and measurement properties, data collection plan, translation to other languages, proxy completion, strategies to minimise missing data and whether PRO data will be monitored during the study to inform clinical care. Conclusions and relevance: These guidelines provide recommendations for items that should be addressed and included in clinical trial Protocols in which PROs are a primary or key secondary outcome. Improved design of clinical trials including PROs could help ensure high-quality data that may inform patient-centered care
