Efficient and gentle delivery of molecules into cells with different elasticity via Progressive Mechanoporation

Intracellular delivery of cargo molecules such as membrane-impermeable proteins or drugs is crucial for cell treatment in biological and medical applications. Recently, microfluidic mechanoporation techniques have enabled transfection of previously inaccessible cells. These techniques create transient pores in the cell membrane by shear-induced or constriction contact-based rapid cell deformation. However, cells deform and recover differently from a given extent of shear stress or compression and it is unclear how the underlying mechanical properties affect the delivery efficiency of molecules into cells. In this study, we identify cell elasticity as a key mechanical determinant of delivery efficiency leading to the development of “progressive mechanoporation” (PM), a novel mechanoporation method that improves delivery efficiency into cells of different elasticity. PM is based on a multistage cell deformation, through a combination of hydrodynamic forces that pre-deform cells followed by their contact-based compression inside a PDMS-based device controlled by a pressure-based microfluidic controller. PM allows processing of small sample volumes (about 20 μL) with high-throughput (>10 000 cells per s), while controlling both operating pressure and flow rate for a reliable and reproducible cell treatment. We find that uptake of molecules of different sizes is correlated with cell elasticity whereby delivery efficiency of small and big molecules is favoured in more compliant and stiffer cells, respectively. A possible explanation for this opposite trend is a different size, number and lifetime of opened pores. Our data demonstrates that PM reliably and reproducibly delivers impermeable cargo of the size of small molecule inhibitors such as 4 kDa FITC-dextran with >90% efficiency into cells of different mechanical properties without affecting their viability and proliferation rates. Importantly, also much larger cargos such as a >190 kDa Cas9 protein–sgRNA complex are efficiently delivered high-lighting the biological, biomedical and clinical applicability of our findings

Efficient and gentle delivery of molecules into cells with different elasticity via Progressive Mechanoporation.

Intracellular delivery of cargo molecules such as membrane-impermeable proteins or drugs is crucial for cell treatment in biological and medical applications. Recently, microfluidic mechanoporation techniques have enabled transfection of previously inaccessible cells. These techniques create transient pores in the cell membrane by shear-induced or constriction contact-based rapid cell deformation. However, cells deform and recover differently from a given extent of shear stress or compression and it is unclear how the underlying mechanical properties affect the delivery efficiency of molecules into cells. In this study, we identify cell elasticity as a key mechanical determinant of delivery efficiency leading to the development of "progressive mechanoporation" (PM), a novel mechanoporation method that improves delivery efficiency into cells of different elasticity. PM is based on a multistage cell deformation, through a combination of hydrodynamic forces that pre-deform cells followed by their contact-based compression inside a PDMS-based device controlled by a pressure-based microfluidic controller. PM allows processing of small sample volumes (about 20 μL) with high-throughput (>10 000 cells per s), while controlling both operating pressure and flow rate for a reliable and reproducible cell treatment. We find that uptake of molecules of different sizes is correlated with cell elasticity whereby delivery efficiency of small and big molecules is favoured in more compliant and stiffer cells, respectively. A possible explanation for this opposite trend is a different size, number and lifetime of opened pores. Our data demonstrates that PM reliably and reproducibly delivers impermeable cargo of the size of small molecule inhibitors such as 4 kDa FITC-dextran with >90% efficiency into cells of different mechanical properties without affecting their viability and proliferation rates. Importantly, also much larger cargos such as a >190 kDa Cas9 protein-sgRNA complex are efficiently delivered high-lighting the biological, biomedical and clinical applicability of our findings

Effects of a scalable home-visiting intervention on child development in slums of urban India: evidence from a randomised controlled trial

Background: An estimated 63.4 million Indian children under 5 years are at risk of poor development. Home visits that use a structured curriculum to help caregivers enhance the quality of the home stimulation environment improve developmental outcomes. However, achieving effectiveness in poor urban contexts through scalable models remains challenging. Methods: Using a cluster randomised controlled trial, we evaluated a psychosocial stimulation intervention, comprising weekly home visits for 18 months, in urban slums of Cuttack, Odisha, India. The intervention is complementary to existing early childhood services in India and was run and managed through a local branch of a national NGO. The study ran from August 2013 to July 2015. We enrolled 421 children aged 10–20 months from 54 slums. Slums were randomised to intervention or control. Primary outcomes were children's cognitive, receptive language, expressive language and fine motor development assessed using the Bayley‐III. Prespecified intent‐to‐treat analysis investigated impacts and heterogeneity by gender. Trial registrations: ISRCTN89476603, AEARCTR‐0000169. Results: Endline data for 378 (89.8%) children were analysed. Attrition was balanced between groups. We found improvements of 0.349 of a standard deviation (SD; p = .005, stepdown p = .017) to cognition while impacts on receptive language, expressive language and fine motor development were, respectively, 0.224 SD (p = .099, stepdown p = .184), 0.192 SD (p = .085, stepdown p = .184) and 0.111 (p = .385, stepdown p = .385). A child development factor improved by 0.301 SD (p = .032). Benefits were larger for boys. The quality of the home stimulation environment also improved. Conclusions: This study shows that a potentially scalable home‐visiting intervention is effective in poor urban areas

Research in hydraulic brake components and operational factors influencing the hysteresis losses

Up-to-date automotive brake systems place stringent requirements upon the performance, reliability, and active safety. Such advanced systems as antilock braking systems (ABS), the electronic stability programme system, and the anti-slip control system assist a driver in ensuring driving safety under many conditions. The influence of the brake components on active safety systems is mainly determined through the hysteresis loop width. Among other negative outcomes, this parameter limits the possible frequency of cyclic braking during ABS operation. This paper presents an experimental analysis of the factors influencing the hysteresis pressure losses in a hydraulic brake system. The factors under investigations are the brake pedal stroke velocity, the gaps between the brake pads and the brake disc, and the configuration of the brake system. Experiments were carried out on the brake test equipment at the Automotive Engineering Department, Faculty for Mechanical Engineering, Technische Universität Ilmenau, Germany

Poverty and Wellbeing Impacts of Microfinance : What Do We Know?

Over the last 35 years, microfinance has been generally regarded as an effective policy tool in the fight against poverty. Yet, the question of whether access to credit leads to poverty reduction and improved wellbeing remains open. To address this question, we conduct a systematic review of the quantitative literature of microfinance’s impacts in the developing world, and develop a theory of change that links inputs to impacts on several welfare outcomes. Overall, we find that the limited comparability of outcomes and the heterogeneity of microfinance-lending technologies, together with a considerable variation in socio-economic conditions and contexts in which impact studies have been conducted, render the interpretation and generalization of findings intricate. Our results indicate that, at best, microfinance induces short-term dynamism in the financial life of the poor; however, we do not find compelling evidence that this dynamism leads to increases in income, consumption, human capital and assets, and, ultimately, a reduction in poverty

COVID-19 vaccine acceptance and hesitancy in low- and middle-income countries

Widespread acceptance of COVID-19 vaccines is crucial for achieving sufficient immunization coverage to end the global pandemic, yet few studies have investigated COVID-19 vaccination attitudes in lower-income countries, where large-scale vaccination is just beginning. We analyze COVID-19 vaccine acceptance across 15 survey samples covering 10 low- and middle-income countries (LMICs) in Asia, Africa and South America, Russia (an upper-middle-income country) and the United States, including a total of 44,260 individuals. We find considerably higher willingness to take a COVID-19 vaccine in our LMIC samples (mean 80.3%; median 78%; range 30.1 percentage points) compared with the United States (mean 64.6%) and Russia (mean 30.4%). Vaccine acceptance in LMICs is primarily explained by an interest in personal protection against COVID-19, while concern about side effects is the most common reason for hesitancy. Health workers are the most trusted sources of guidance about COVID-19 vaccines. Evidence from this sample of LMICs suggests that prioritizing vaccine distribution to the Global South should yield high returns in advancing global immunization coverage. Vaccination campaigns should focus on translating the high levels of stated acceptance into actual uptake. Messages highlighting vaccine efficacy and safety, delivered by healthcare workers, could be effective for addressing any remaining hesitancy in the analyzed LMICs.Publisher PDFPeer reviewe

Co-designing transformation research : lessons learned from research on deliberate practices for transformation

Co-production of new knowledge can enhance open and integrative research processes across the social and natural sciences and across research/science, practice and policy interrelationships. Thus, co-production is important in the conduct of research about and for transformations to sustainability. While co-design is an integral part of co-production, it often receives limited attention in the conduct of co-produced research. This paper reports on lessons learned from an early stage of the co-design process to develop research on deliberate practices for transformative change. Key lessons learned are the need to: (1) ensure co-design processes are themselves carefully designed; (2) encourage emergence of new ways of thinking about problem formulation through co-design; (3) carefully balance risks for the participants involved while also enhancing opportunities for intellectual risk taking; (4) facilitate personal transformations in co-design as a way to stimulate and encourage further creativity; and (5) for funders to carefully and constructively align criteria or incentives through which a project or future proposal will be judged to the goals of the co-design, including for instrumental outcomes and objectives for creativity and imagination. Given that co-design necessarily involves a reflective practice to iteratively guide emergence of new thinking about the practices of change, co-design can itself be considered an important deliberate practice for transforming the conduct of research and the contribution of that research to social transformations

Learning from Poverty: Why Business Schools Should Address Poverty, and How They Can Go About It.

In the past few years, business schools have begun to address poverty issues in their teaching, learning and curricula. While this is a positive development, the arguments for reconfiguring educational programs to address such matters remain undeveloped, with much of the impetus for such endeavors rooted in calls for social responsibility in the United Nations Millennium Development Goals, the Social Compact, the Principles for Responsible Management Education and benchmarks such as ISO 26000. This article seeks to clarify the pedagogical grounds for integrating poverty issues in management education by examining the intellectual and personal development benefits of doing so. By critically examining four modes of business involvement in poverty reduction, the article shows how such initiatives can be used as intellectual lenses through which to view the complex and often paradoxical interconnections between socioeconomic and environmental systems. It is thus concluded that a consideration of poverty issues is not a marginal matter, but is key to grasping the 21st century complexities of global business and management