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Kenney E, Rampalli KK, Samin S, Frongillo EA, Reyes LI, Bhandari S, Boncyk M, Nordhagen S, Walls H, Wertheim-Heck S, Ickowitz A, Cunningham SA, Ambikapathi R, Ekesa B, Matita M, Blake CE. How Livelihood Change Affects Food Choice Behaviors in Low- and Middle-Income Countries: A Scoping Review. Adv Nutr 2024; 15:100203. [PMID: 38462217 PMCID: PMC11007434 DOI: 10.1016/j.advnut.2024.100203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 01/29/2024] [Accepted: 03/05/2024] [Indexed: 03/12/2024] Open
Abstract
Livelihoods have changed dramatically over the past decade in low- and middle-income countries (LMIC). These shifts are happening in tandem with shifts in individual and household food choice behaviors. This scoping review aimed to identify and characterize mechanisms through which livelihood changes could affect food choice behaviors in LMIC, including behaviors relating to food production, acquisition, preparation, distribution, and consumption. A literature search was conducted using 4 databases: PubMed, PsycInfo, AGRICOLA, and Embase. The search was further enhanced by expert solicitations. Studies were included if they measured or focused on a livelihood change, described or assessed a change in ≥1 food choice behavior, and focused on LMIC. Studies were excluded if they focused on migration from LMIC to a high-income country. Of the 433 articles that were identified, 53 met the inclusion criteria. Five mechanisms of how livelihood change can affect food choice were identified: occupation, locality, time, income, and social relations. Changes in occupation altered the balance of the availability and affordability of foods in local food environments compared with individual food production. Changes in location, time use, and income influenced where food was purchased, what types of foods were acquired, and how or where foods were prepared. Additionally, changes in social relationships and norms led to expanded food preferences, particularly among urban populations. Time limitations and higher discretionary income were associated with consumption of ultraprocessed foods. Understanding the relationships between the changes in livelihood occuring in LMIC and food choices of households in these countries can inform the development of policies, programs, and other actions to promote sustainable healthy diets and planetary health.
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Affiliation(s)
- Emma Kenney
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, United States.
| | - Krystal K Rampalli
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, United States
| | - Sharraf Samin
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, United States
| | - Edward A Frongillo
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, United States
| | - Ligia I Reyes
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, United States; Division of Nutritional Science, College of Human Ecology, Cornell University, Ithaca, NY, United States
| | - Shiva Bhandari
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, United States
| | - Morgan Boncyk
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, United States; Department of Public Health, Purdue University, West Lafayette, IN, United States
| | - Stella Nordhagen
- Global Alliance for Improved Nutrition (GAIN), Geneva, Switzerland
| | - Helen Walls
- Department of Global Health and Development, Faculty of Public Health and Policy, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Sigrid Wertheim-Heck
- Environmental Policy Group, Department of Social Sciences, Wageningen University, Wageningen, The Netherlands
| | - Amy Ickowitz
- Center for International Forestry Research-World Agroforestry Center, Beit Zayit, Israel
| | - Solveig A Cunningham
- Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Ramya Ambikapathi
- Department of Public Health, Purdue University, West Lafayette, IN, United States; Department of Global Development, College of Agriculture and Life Sciences, Cornell University, Ithaca, NY, United States
| | - Beatrice Ekesa
- Alliance of Bioversity International and CIAT, Kampala, Uganda
| | - Mirriam Matita
- Extension Department, Lilongwe University of Agriculture and Natural Resources, Lilongwe, Malawi
| | - Christine E Blake
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, United States
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Fishbein EM, Frongillo EA, Samin S, Richards AL, Blake CE, Saunders RP, Shapiro CJ. Understanding Commitment of Local Food Banks, Faith-Based Organizations, and Schools to Provide Nongovernment Food Programs. Curr Dev Nutr 2023; 7:102005. [PMID: 37877036 PMCID: PMC10590716 DOI: 10.1016/j.cdnut.2023.102005] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 09/08/2023] [Accepted: 09/14/2023] [Indexed: 10/26/2023] Open
Abstract
Background Nongovernment food assistance is typically provided to families by faith-based organizations, schools, and food banks. Community organizations appear to be strongly committed to these programs, but little is known about the basis for this commitment. Objectives The aim of this study was to examine the values and identities of community organizations to understand the reasons for their commitment to providing nongovernment food assistance. Methods Thirty-three in-depth interviews were conducted with 36 leaders at faith-based organizations (19 participants), schools (14 participants), and a local food bank (3 participants) in South Carolina. Observations were made, and informational documents (e.g., flyers and pamphlets) were reviewed. Thematic coding using the constant comparative method was guided by the policy concepts of organizational perspectives, values, and identities. Results Nongovernment food programs offered participants volunteering opportunities to become involved with community organizations, which in turn increased financial support for the sustainability of these programs. School participants regarded themselves as a mechanism through which food programs were provided because of their commitment to students and believed they have limited capacity to make proposals to influence the food programs. Seeking to improve the well-being of the community by ending hunger was not the primary value on which organizations focused; instead, it was the process of fulfilling other values (e.g., forming or maintaining relationships within the community), maintaining identity, and appealing to their participants that strengthened their commitment to nongovernment food programs. Conclusion Nongovernment programs are meant to be a solution to food insecurity complementary to government programs. Commitment to nongovernment programs fulfills organizational identities, wants, and assumptions, but a consequence of commitment to food programs, derived from fulfilling other values, is that the roots of hunger in a community become obscured and alternative solutions are ignored or rejected.
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Affiliation(s)
- Eliza M. Fishbein
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, United States
| | - Edward A. Frongillo
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, United States
| | - Sharraf Samin
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, United States
| | - Audrey L. Richards
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, United States
| | - Christine E. Blake
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, United States
| | - Ruth P. Saunders
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, United States
| | - Cheri J. Shapiro
- Institute for Families in Society, University of South Carolina, Columbia, SC, United States
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Isanovic S, Constantinides SV, Frongillo EA, Bhandari S, Samin S, Kenney E, Wertheim-Heck S, Nordhagen S, Holdsworth M, Dominguez-Salas P, Ambikapathi R, Laar A, Patil CL, Kulkarni B, Bukachi SA, Ngutu M, Blake CE. How Perspectives on Food Safety of Vendors and Consumers Translate into Food-Choice Behaviors in 6 African and Asian Countries. Curr Dev Nutr 2023; 7:100015. [PMID: 37181131 PMCID: PMC10100931 DOI: 10.1016/j.cdnut.2022.100015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 10/30/2022] [Accepted: 11/22/2022] [Indexed: 12/24/2022] Open
Abstract
Background Consumption of unsafe foods increases morbidity and mortality and is currently an issue, particularly in low- and middle-income countries. Policy actions to ensure food safety are dominated by mitigation of biological and chemical hazards through supply-side risk management, lessening the degree to which consumer perspectives of food safety are considered. Objectives This study aimed to provide an in-depth understanding, from vendor and consumer perspectives, of how food-safety concerns of consumers translate into their subsequent food-choice behaviors in 6 diverse low- and middle-income countries. Methods Six Drivers of Food Choice projects (2016-2022) provided transcripts from 17 focus group discussions and 343 interviews conducted in Ghana, Guinea, India, Kenya, Tanzania, and Vietnam. Qualitative thematic analysis was used to identify emerging themes important to food safety. Results The analysis suggests that consumers constructed meaning about food safety through personal lived experience and social influences. Community and family members contributed knowledge about food safety. Concerns about food safety were influenced by reputations of and relationships with food vendors. Consumers' mistrust of food vendors was amplified by purposeful adulteration or unsafe selling practices and new methods used to produce food. Moreover, consumers were reassured of food safety by positive relationships with vendors; meals cooked at home; implementation of policies and following regulations; vendor adherence to environmental sanitation and food-hygiene practices; cleanliness of vendors' appearance; and vendors' or producers' agency to use risk mitigation strategies in production, processing, and distribution of food. Conclusions Consumers integrated their meanings, knowledge, and concerns about food safety to achieve assurance about the safety of their foods when making food-choice decisions. The success of food-safety policies hinges on consideration of consumers' food-safety concerns in their design and implementation, alongside actions to reduce risk in food supply.
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Affiliation(s)
- Sejla Isanovic
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA
| | - Shilpa V. Constantinides
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA
| | - Edward A. Frongillo
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA
| | - Shiva Bhandari
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA
| | - Sharraf Samin
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA
| | - Emma Kenney
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA
| | - Sigrid Wertheim-Heck
- Environmental Policy Group, Department of Social Sciences, Wageningen University, Wageningen, the Netherlands
| | | | - Michelle Holdsworth
- Montpellier Interdisciplinary Center on Sustainable Agri-food Systems, University of Montpellier, French Agricultural Research Centre for International Development, International Center for Advanced Mediterranean Agronomic Studies, Mediterranean Agronomic Institute of Montpellier, French National Institute for Agricultural Research, Institut Agro, French National Research Institute for Sustainable Development, Montpellier, France
| | - Paula Dominguez-Salas
- Natural Resources Institute, University of Greenwich, London, United Kingdom
- International Livestock Research Institute, Nairobi, Kenya
| | - Ramya Ambikapathi
- Department of Public Health, Purdue University, West Lafayette, IN, USA
- Department of Global Development, Cornell University, Ithaca, NY, USA
| | - Amos Laar
- University of Ghana, Department of Population, Family and Reproductive Health, School of Public Health, Accra, Ghana
| | - Crystal L. Patil
- Department of Human Development Nursing Science, University of Illinois–Chicago, Chicago, IL, USA
| | - Bharati Kulkarni
- Division of Reproductive Biology, Maternal and Child Health and Nutrition, Indian Council of Medical Research, V. Ramalingaswami Bhawan, New Delhi, India
| | - Salome A. Bukachi
- Institute of Anthropology, Gender and African Studies, University of Nairobi, Nairobi, Kenya
| | - Mariah Ngutu
- Institute of Anthropology, Gender and African Studies, University of Nairobi, Nairobi, Kenya
| | - Christine E. Blake
- Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA
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Rahman KMT, Khalequzzaman M, Khan FA, Rayna SE, Samin S, Hasan M, Islam SS. Factors associated with the nutritional status of the older population in a selected area of Dhaka, Bangladesh. BMC Geriatr 2021; 21:161. [PMID: 33673811 PMCID: PMC7934473 DOI: 10.1186/s12877-021-02068-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 01/21/2021] [Indexed: 11/20/2022] Open
Abstract
Background Globally, older population (aged ≥60 years) comprise 11% of the total population, and 23% of them are malnourished. Lack of knowledge and education, adverse dietary habits, depression or psychological disorders, poor oral and dental health, disability, and diseases are the reported factors responsible for malnutrition among them. Geriatric people comprise 7.5% of the total population of Bangladesh, and almost a quarter are malnourished. But there is scarce data on the factors associated with the nutritional status of the older population in Bangladesh. Methods A cross-sectional study was conducted among 125 older individuals (male 59, female 66) living in three villages of Uttarkhan, Dhaka, Bangladesh, to identify the factors associated with their nutritional status. The Mini Nutritional Assessment scale, Geriatric Depression Scale-Short Form, and Geriatric Oral Health Assessment Index were used for assessing the nutritional status, mental health status, and oral health quality of the respondents, respectively. Information on socio-demographic characteristics, comorbidities and dietary factors, and food behaviors were gathered by a pretested semi-structured questionnaire. Ethical approval was obtained from the Institutional Review Board of Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh. Results The participants’ mean age was 67.9 ± 7.1 years. Most of them (53.6%) had no formal education. Among the respondents, 22.0% male and 28.8% female were malnourished. The proportion of malnourished and at risk of malnutrition among the respondents living without a partner were 28.6 and 65.3%, respectively. A significantly (p < 0.05) higher odds of having depression (OR 15.6; 95% CI 3.1–78.1), poor oral health (OR 7.3; 95% CI 1.3–41.8), and no formal education (OR 6.5; 95% CI 1.3–32.1) was observed among the malnourished respondents. Though it was not statistically significant, among the malnourished, 31.3, 25.0 and 25.0% avoided highly oily food, beef/mutton, and sugary food, respectively. Conclusions More than two-thirds of the older population were malnourished or at risk of malnutrition, where the female respondents were more vulnerable. Depression, inadequate oral health, and lack of education were negatively associated with the nutritional status of the older population.
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Affiliation(s)
- K M Thouhidur Rahman
- Department of Public Health and Informatics, Bangabandhu Sheikh Mujib Medical University, Room # 309, Block # B, Shahbag, Dhaka, 1000, Bangladesh
| | - Md Khalequzzaman
- Department of Public Health and Informatics, Bangabandhu Sheikh Mujib Medical University, Room # 309, Block # B, Shahbag, Dhaka, 1000, Bangladesh.
| | - Fahmida Afroz Khan
- Department of Public Health and Informatics, Bangabandhu Sheikh Mujib Medical University, Room # 309, Block # B, Shahbag, Dhaka, 1000, Bangladesh
| | - Shahrin Emdad Rayna
- Department of Public Health and Informatics, Bangabandhu Sheikh Mujib Medical University, Room # 309, Block # B, Shahbag, Dhaka, 1000, Bangladesh
| | - Sharraf Samin
- Department of Public Health and Informatics, Bangabandhu Sheikh Mujib Medical University, Room # 309, Block # B, Shahbag, Dhaka, 1000, Bangladesh
| | - Md Hasan
- Department of Public Health and Informatics, Bangabandhu Sheikh Mujib Medical University, Room # 309, Block # B, Shahbag, Dhaka, 1000, Bangladesh
| | - Syed Shariful Islam
- Department of Public Health and Informatics, Bangabandhu Sheikh Mujib Medical University, Room # 309, Block # B, Shahbag, Dhaka, 1000, Bangladesh
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Werkhoven BL, Everts JC, Samin S, van Roij R. Flow-Induced Surface Charge Heterogeneity in Electrokinetics due to Stern-Layer Conductance Coupled to Reaction Kinetics. Phys Rev Lett 2018; 120:264502. [PMID: 30004760 DOI: 10.1103/physrevlett.120.264502] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 05/18/2018] [Indexed: 06/08/2023]
Abstract
We theoretically study the electrokinetic problem of a pressure-induced liquid flow through a narrow long channel with charged walls, going beyond the classical Helmholtz-Schmolukowski picture by considering the surprisingly strong combined effect of (i) Stern-layer conductance and (ii) dynamic charge-regulating rather than fixed surface charges. We find that the water flow induces, apart from the well-known streaming potential, also a strongly heterogeneous surface charge and zeta potential on chemically homogeneous channel walls. Moreover, we identify a novel steady state with a nontrivial 3D electric flux with 2D surface charges acting as sources and sinks. For a pulsed pressure drop our findings also provide a first-principles explanation for ill-understood experiments on the effect of flow on interfacial chemistry [D. Lis et al., Science 344, 1138 (2014)SCIEAS0036-807510.1126/science.1253793].
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Affiliation(s)
- B L Werkhoven
- Institute for Theoretical Physics, Center for Extreme Matter and Emergent Phenomena, Utrecht University, Princetonplein 5, 3584 CC, Utrecht, The Netherlands
| | - J C Everts
- Department of Physics, Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19, 1000 Ljubljana, Slovenia
| | - S Samin
- Institute for Theoretical Physics, Center for Extreme Matter and Emergent Phenomena, Utrecht University, Princetonplein 5, 3584 CC, Utrecht, The Netherlands
| | - R van Roij
- Institute for Theoretical Physics, Center for Extreme Matter and Emergent Phenomena, Utrecht University, Princetonplein 5, 3584 CC, Utrecht, The Netherlands
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6
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Debnath SC, Haque ME, Hasan DMM, Samin S, Rouf MA, Rabby MF. Undernutrition and Morbidity Profile of Exclusively Breastfeeding Children: A Cross-sectional Study. Int J Prev Med 2018; 9:55. [PMID: 30050666 PMCID: PMC6036768 DOI: 10.4103/ijpvm.ijpvm_201_17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 09/02/2017] [Indexed: 11/26/2022] Open
Abstract
Background: Undernutrition is common and has been recognized as a public health problem in Bangladesh. It has devastating effects on any population as it increases morbidity children and reduces the quality of life of all affected. The study was done with the objective to assess the undernutrition and morbidity profile in children who have completed exclusive breastfeeding. Methods: This was a descriptive cross-sectional study, which was carried out among children aged 6–12 completed months attending a tertiary level hospital in Bangladesh. A total of 251 children were selected through convenient sampling from January to December 2015. Nutritional assessment was done in terms of underweight, stunting, and wasting. Results: One hundred and forty-three (57.0%) were boys while 108 (43.0%) were girls. The prevalence of undernutrition (Z-score ≤−2) was observed in 11.2%, 16.3%, and 12.0% based on stunting, underweight, and wasting. Among 251 children, 16.7% were not suffering any diseases, whereas majorities (69.7%) were suffering from single disease and 13.5% were suffering from multiple diseases. Cough and fever (55.0%), pneumonia (18.3%), measles (9.9%), and diarrhea (8.3%) were the most common cause of infectious morbidity observed in children. Conclusions: The prevalence of undernutrition was high in the study population, and it continues to be a public health burden because of its major effect on morbidity and impairment of intellectual and physical development in long-term. Increasing the practice of exclusive breastfeeding, the introduction of timely complementary feeding, and standard case management of morbidities would be beneficial to combat the problem of undernutrition.
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Affiliation(s)
| | - Md Ekramul Haque
- Communicable Disease Control (CDC), DGHS, Mohakhali, Dhaka, Bangladesh
| | | | - Sharraf Samin
- TB/HIV Control Program, BRAC, BRAC Centre, Mohakhali, Dhaka, Bangladesh
| | - Md Abdur Rouf
- Aichi Medical College and Hospital, Dhaka, Bangladesh
| | - Md Fazlay Rabby
- Associates for Community and Population Research, Dhaka, Bangladesh
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7
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Hod M, Dobroserdova A, Samin S, Dobbrow C, Schmidt AM, Gottlieb M, Kantorovich S. Dilution effects on combined magnetic and electric dipole interactions: A study of ferromagnetic cobalt nanoparticles with tuneable interactions. J Chem Phys 2017; 147:084901. [DOI: 10.1063/1.4995428] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- M. Hod
- Chemical Engineering Department, Ben Gurion University of the Negev, Beer Sheva 84105 Israel
| | - A. Dobroserdova
- Ural Federal University, Lenin Ave. 51, 620083 Ekaterinburg, Russia
| | - S. Samin
- Chemical Engineering Department, Ben Gurion University of the Negev, Beer Sheva 84105 Israel
- Institute for Theoretical Physics, Center for Extreme Matter and Emergent Phenomena, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
| | - C. Dobbrow
- Institut für Physikalische Chemie, Department Chemie, Universität zu Köln, Luxemburger Str. 116, D-50939 Köln, Germany
| | - A. M. Schmidt
- Institut für Physikalische Chemie, Department Chemie, Universität zu Köln, Luxemburger Str. 116, D-50939 Köln, Germany
| | - M. Gottlieb
- Chemical Engineering Department, Ben Gurion University of the Negev, Beer Sheva 84105 Israel
| | - S. Kantorovich
- Computational Physics, University of Vienna, Sensengasse 8, 1090 Vienna, Austria
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8
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Chung S, Samin S, Holm C, Malherbe JG, Amokrane S. Dynamics of field-driven population inversion in a confined colloidal mixture. Phys Rev E 2017; 95:022605. [PMID: 28297870 DOI: 10.1103/physreve.95.022605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Indexed: 11/07/2022]
Abstract
We study, using Langevin dynamics simulations, the change in composition of a binary colloidal mixture confined in a finite-length channel, induced by an external field. The field-induced transition from a near-bulk composition to an inverted population is studied as a function of time, for different field strengths and system parameters. For state points corresponding to reversible field cycles, the cyclic filling and emptying of the channel by the minority species are compared. Extrapolation of the physical relaxation times to the colloidal regime is performed through a series of simulations at increasing value of the damping parameter. For state points at which the mixture is unstable at zero field, reproducible irreversible cycles are illustrated. For reversible field cycles, the scaling with the particles size of the characteristic cycling time is discussed.
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Affiliation(s)
- S Chung
- Physique des Liquides et Milieux Complexes, Faculté des Sciences et Technologie, Université Paris-Est (Créteil), 61 Avenue du Général de Gaulle, 94010 Créteil Cedex, France
| | - S Samin
- Center for Extreme Matter and Emergent Phenomena, Institute for Theoretical Physics, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
| | - C Holm
- Institute for Computational Physics, Universität Stuttgart, Allmandring 3, 70569 Stuttgart Germany
| | - J G Malherbe
- Physique des Liquides et Milieux Complexes, Faculté des Sciences et Technologie, Université Paris-Est (Créteil), 61 Avenue du Général de Gaulle, 94010 Créteil Cedex, France
| | - S Amokrane
- Physique des Liquides et Milieux Complexes, Faculté des Sciences et Technologie, Université Paris-Est (Créteil), 61 Avenue du Général de Gaulle, 94010 Créteil Cedex, France
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9
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Everts JC, Samin S, Elbers NA, van der Hoeven JES, van Blaaderen A, van Roij R. Colloid–oil–water-interface interactions in the presence of multiple salts: charge regulation and dynamics. Phys Chem Chem Phys 2017; 19:14345-14357. [DOI: 10.1039/c7cp01935a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The salt-induced dislodgement of charged colloidal particles from an oil–water interface is investigated theoretically and experimentally.
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Affiliation(s)
- J. C. Everts
- Institute for Theoretical Physics
- Center for Extreme Matter and Emergent Phenomena
- Utrecht University
- 3584 CC Utrecht
- The Netherlands
| | - S. Samin
- Institute for Theoretical Physics
- Center for Extreme Matter and Emergent Phenomena
- Utrecht University
- 3584 CC Utrecht
- The Netherlands
| | - N. A. Elbers
- Soft Condensed Matter
- Debye Institute for Nanomaterials Science
- Utrecht
- The Netherlands
| | | | - A. van Blaaderen
- Soft Condensed Matter
- Debye Institute for Nanomaterials Science
- Utrecht
- The Netherlands
| | - R. van Roij
- Institute for Theoretical Physics
- Center for Extreme Matter and Emergent Phenomena
- Utrecht University
- 3584 CC Utrecht
- The Netherlands
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10
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Abstract
We show that the interaction of an oil-dispersed colloidal particle with an oil-water interface is highly tunable from attractive to repulsive, either by varying the sign of the colloidal charge via charge regulation or by varying the difference in hydrophilicity between the dissolved cations and anions. In addition, we investigate the yet unexplored interplay between the self-regulated colloidal surface charge distribution with the planar double layer across the oil-water interface and the spherical one around the colloid. Our findings explain recent experiments and have direct relevance for tunable Pickering emulsions.
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Affiliation(s)
- J C Everts
- Institute for Theoretical Physics, Center for Extreme Matter and Emergent Phenomena, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
| | - S Samin
- Institute for Theoretical Physics, Center for Extreme Matter and Emergent Phenomena, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
| | - R van Roij
- Institute for Theoretical Physics, Center for Extreme Matter and Emergent Phenomena, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
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11
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Everts JC, Punter MTJJM, Samin S, van der Schoot P, van Roij R. A Landau-de Gennes theory for hard colloidal rods: Defects and tactoids. J Chem Phys 2016; 144:194901. [DOI: 10.1063/1.4948785] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- J. C. Everts
- Institute for Theoretical Physics, Center for Extreme Matter and Emergent Phenomena, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
| | | | - S. Samin
- Institute for Theoretical Physics, Center for Extreme Matter and Emergent Phenomena, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
| | - P. van der Schoot
- Institute for Theoretical Physics, Center for Extreme Matter and Emergent Phenomena, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
- Theory of Polymers and Soft Matter Group, Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
| | - R. van Roij
- Institute for Theoretical Physics, Center for Extreme Matter and Emergent Phenomena, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
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