869 research outputs found
Electrochemical Behavior, Microstructural Analysis, and Morphological Observations in Reinforced Mortar Subjected to Chloride Ingress
Enhancement of CO2 conversion by counterflow gas quenching of the post-discharge region in microwave plasma sustained by gyrotron radiation
A threefold increase in the CO2 conversion and energy efficiency due to the
cooling of the post-discharge region by the counter gas flow has been achieved
in the plasma of an atmospheric pressure discharge supported by microwave
radiation of a gyrotron with a frequency of 24 GHz in a carbon dioxide gas
flow. The role of convective heat transfer in the process of gas mixture
cooling in the post-discharge region has been experimentally demonstrated. At
nitrogen quench gas flow of 4.5 l/min, the CO2 conversion was 23.8 % and energy
efficiency was 19.7 %. The possibility of using the flow of cooled gas mixture
(CO2,CO,O2) taken from the reactor as quenching gas has been experimentally
demonstrated, which made it possible to achieve a CO2 conversion degree of 23.4
% and to eliminate the problem of dilution of reaction products by third-party
gases. Based on numerical modeling, it is shown that the increase in the
conversion degree upon the destruction of the plasma torch structure is due to
the increase in heat exchange with the surrounding atmosphere, and the
efficiency of this destruction is determined by the velocity and density of
quenching gas.Comment: 20 pages, 14 pages, submitted to the Journal of Energy Chemistry
28.11.202
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
Development, Citizenship, and Everyday Appropriations of Buen Vivir: Ecuadorian Engagement with the Changing Rhetoric of Improvement
The Ecuadorian state frames its development interventions in infrastructure and human capital as advances in buen vivir or ‘good living’. This paper reports ethnographic research that draws attention to everyday appropriations of state discourses on buen vivir in the Amazon and Andes. Non-state actors in marginalised communities often use state discourses strategically in engagements and negotiations with state actors. We argue that uses of official versions of buen vivir discourse often reflect such strategic appropriations of state idioms, rather than subjective commitment to state-led development and official notions of buen vivir
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
Post-agrarian aspirations: tourism and rural politics in Ecuador
This ethnographic study examines post-agrarian aspirations and rural politics in Ecuador. After decades of urban outmigration under a neoliberal agrarian order, many rural places have witnessed efforts to develop local tourism economies as a possibility to transcend stigmatised agrarian livelihoods and to (re)constitute communities. We build on anthropological studies of aspiration to explore how visions of post-agrarian futures are shifting the actors, scales and terms of rural politics in the present. Through two case studies, we observe how state actors have come to re-inscribe their role within post-agrarian imaginaries, partially rewriting the terms of state legitimacy in rural places
An investigation of copper corrosion inhibition in chloride solutions by benzo-hydroxamic acids
Agroecology, Supply Chains, and COVID-19: Lessons on Food System Transitions from Ecuador
In cities, agroecological food consumption is often identified as an exclusive, middle-class practice. In this article, we examine changes in agroecological food circuits in urban Ecuador, amid COVID-19 breakdowns in conventional food systems. Through interviews with farmers, government officials, and NGO workers in 2020 and 2021, our research identifies three sets of experiences with distinct implications for agroecological transitions. First, some agroecological circuits could no longer function due to regulations on food circulation that favored the corporate food sector. Second, some circuits temporarily expanded to reach more urban middle-class consumers, using online platforms and government infrastructures. Third, urban collectives and neighborhood organizations re-appropriated urban spaces – from cultural centers to city streets – to facilitate the circulation of agroecological foods in low-income sectors. We highlight the spatial and social ‘re-localization’ practices of these urban groups that challenge the hegemony of conventional food circuits, as they drive agroecological food consumption beyond the middle-class
Major differences in organization and availability of health care and medicines for HIV/TB coinfected patients across Europe
Objectives The aim of the study was to investigate the organization and delivery of HIV and tuberculosis (TB) health care and to analyse potential differences between treatment centres in Eastern (EE) and Western Europe (WE). Methods Thirty-eight European HIV and TB treatment centres participating in the TB:HIV study within EuroCoord completed a survey on health care management for coinfected patients in 2013 (EE: 17 respondents; WE:21; 76% of all TB:HIV centres). Descriptive statistics were obtained for regional comparisons. The reported data on health care strategies were compared with actual clinical practice at patient level via data derived from the TB:HIV study. Results Respondent centres in EE comprised: Belarus (n = 3), Estonia (1), Georgia (1), Latvia (1), Lithuania (1), Poland (4), Romania (1), the Russian Federation (4) and Ukraine (1); those in WE comprised: Belgium (1), Denmark (1), France (1), Italy (7), Spain (2), Switzerland (1) and UK (8). Compared with WE, treatment of HIV and TB in EE are less often located at the same site (47% in EE versus 100% in WE; P < 0.001) and less often provided by the same doctors (41% versus 90%, respectively; P = 0.002), whereas regular screening of HIV-infected patients for TB (80% versus 40%, respectively; P = 0.037) and directly observed treatment (88% versus 20%, respectively; P < 0.001) were more common in EE. The reported availability of rifabutin and second- and third-line anti-TB drugs was lower, and opioid substitution therapy (OST) was available at fewer centres in EE compared with WE (53% versus 100%, respectively; P < 0.001). Conclusions Major differences exist between EE and WE in relation to the organization and delivery of health care for HIV/TB-coinfected patients and the availability of anti-TB drugs and OST. Significant discrepancies between reported and actual clinical practices were found in EE
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