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Hydrodynamics and mass transfer in liquid-liquid non-circular microchannels : Comparison of two aspect ratios and three junction structures
Hydrodynamics and mass transfer in liquid-liquid slug flow inside a square microchannel (MC-1, aspect ratio 1) and a rectangular microchannel (MC-2, aspect ratio 2) with identical hydraulic diameter (400 µm) were investigated experimentally. The results showed that the overall volumetric mass transfer coefficient (KLa) in MC-2 was 16.2% lower than that in MC-1 due to enlargement of the dispersed p
Salicylic acid-dependent plant stress signaling via mitochondrial succinate dehydrogenase
Mitochondria are known for their role in ATP production and generation of reactive oxygen species, but little is known about the mechanism of their early involvement in plant stress signaling. The role of mitochondrial succinate dehydrogenase (SDH) in salicylic acid (SA) signaling was analyzed using two mutants: disrupted in stress response1 (dsr1), which is a point mutation in SDH1 identified in
The transcription factor MYB29 is a regulator of alternative oxidase1a
Plants sense and integrate a variety of signals from the environment through different interacting signal transduction pathways that involve hormones and signaling molecules. Using ALTERNATIVE OXIDASE1a (AOX1a) gene expression as a model system of retrograde or stress signaling between mitochondria and the nucleus, MYB DOMAIN PROTEIN29 (MYB29) was identified as a negative regulator (regulator of a
Estimation of vertical displacement during ascending evacuation
This paper describes an ascending evacuation model based on physical work capacity, when exhaustion may play a key role during evacuation. The experiment was carried out on a stair machine (StairMaster, SM5, USA) which involved 13 male and 12 female subjects. Individual climbing speeds at 50 and 70 % of their maximal aerobic capacity (% VO2max) level (L1 and L2) were selected for 3 minutes, and 90
Perceived home is associated with psychological well-being in a cohort aged 67–70 years
Research on very old people has shown that perceived aspects of home are important for health, but research on such associations in younger cohorts of older people is lacking. The aim of this study was to investigate whether perceived aspects of home were associated with psychological well-being among community-living people aged 67–70. Interview data were collected with 371 individuals living in
Investigation of transient ignition process in a cavity based scramjet combustor using combined ethylene injectors
Large Eddy Simulation (LES) and experiment were employed to investigate the transient ignition and flame propagation process in a rearwall-expansion cavity scramjet combustor using combined fuel injection schemes. The compressible supersonic solver and three ethylene combustion mechanisms were first validated against experimental data and results show in reasonably good agreement. Fuel injection s
Concentration of perfluorinated compounds and cotinine in human foetal organs, placenta, and maternal plasma
Background Perfluoroalkyl substances (PFASs) are bio-accumulative pollutants, and prenatal exposure to PFASs is believed to impact human foetal development and may have long-term adverse health effects later in life. Additionally, maternal cigarette smoking may be associated with PFAS levels. Foetal exposure has previously been estimated from umbilical cord plasma, but the actual concentration in
Optical Diagnostics of Gasoline Compression Ignition : HCCI-PPC-Diffusion Combustion
Access to clean and affordable energy is one of the cornerstones of the world’s society. Sincethe introduction of the internal combustion engine, diesel engines have become widely usedfor transportation in the commercial sector. These engines are attractive as they have lowfuel consumption, but are also associated with high emissions of air pollutants, such asNOX and soot. These emissions are direAccess to clean and affordable energy is one of the cornerstones of the world's society. Since the introduction of the internal combustion engine, diesel engines have become widely used for transportation in the commercial sector. These engines are attractive as they have low fuel consumption, but are also associated with high emissions of air pollutants, such as NO$_X$ and soot. These emissions a
Combined emulsifying capacity of polysaccharide particles of different size and shape
The aim of this study is to understand mixed systems of two types of particles with different size and shape, quinoa starch granules (NQ) and cellulose nanocrystals (CNC), to stabilize oil-in-water (O/W) emulsions. This study considers the extent of Pickering stabilization with respect to which particle type dominates at droplet interfaces and how stability is affected by the addition of one parti
Recent applications of synchrotron radiation and neutrons in the study of soft matter
The broad range of applications of synchrotron and neutron scattering in the investigation of soft condensed matter is reviewed. Appropriate combinations of these techniques allow probing the structure and dynamics of these complex systems from sub-nm to micron size scales and picoseconds to seconds and longer time ranges. Applications include a myriad of systems such as polymers, colloids, surfac
Flow pattern and heat transfer past two tandem arranged cylinders with oscillating inlet velocity
Unsteady laminar convective fluid flow and heat transfer past two cylinders in tandem arrangement is investigated. Besides forced mixing by the natural vortex streets, extra imposed oscillating inlet velocity are considered. The lift and drag coefficients and Strouhal number for a single cylinder and their dependence on Reynolds number are also provided to validate the calculations with previous e
Evaluation of physical work capacity and leg muscle fatigue during exhaustive stair ascending evacuation
AbstractPhysical exhaustion can constrain human ascending work capacity and performance during emergency evacuation on stairs. The overall aim of this research was to explore and compare stair ascending capacities and physiological limitations during two different strategies: self-preferred pace in three different public stairways in the field, and controlled pace in a laboratory on a stair machin
Development and Evaluation of Methods in Source Apportionment of the Carbonaceous Aerosol
Atmosfäriska partiklar (aerosoler) finns överallt i jordens atmosfär. Masskoncentrationen av dessa varierar kraftigt beroende på i vilken miljö man mäter. I stadsluft kan man uppmäta tiotals mikrogram per kubikmeter medan man i arktiska områden uppmäter nanogram per kubikmeter. Den kolhaltiga aerosolen utgör en betydande del av atmosfärsaerosolens massa och är känd för att påverka människors och dCarbonaceous aerosols are known to affect human health negatively and to affect the climate of Earth. As specific types of aerosols originate from specific sources, it is important to know the amount of aerosols emitted from each source. Aerosol source apportionment is an important tool in mitigating air pollution and improving air quality. The subject of this thesis was the evaluation and develop
The Mitochondrial DNA (mtDNA)-Associated Protein SWIB5 Influences mtDNA Architecture and Homologous Recombination
In addition to the nucleus, mitochondria and chloroplasts in plant cells also contain genomes. Efficient DNA repair pathways are crucial in these organelles to fix damage resulting from endogenous and exogenous factors. Plant organellar genomes are complex compared to their animal counterparts and although several plant-specific mediators of organelle DNA repair have been reported, many regulators
Retrograde signalling caused by heritable mitochondrial dysfunction is partially mediated by ANAC017 and improves plant performance
Mitochondria are crucial for plant viability and are able to communicate information on their functional status to the cellular nucleus via retrograde signalling, thereby affecting gene expression. It is currently unclear if retrograde signalling in response to constitutive mitochondrial biogenesis defects is mediated by the same pathways as those triggered during acute mitochondrial dysfunction.
Mitochondrial and Chloroplast Stress Responses Are Modulated in Distinct Touch and Chemical Inhibition Phases
Previous studies have identified a range of transcription factors that modulate retrograde regulation of mitochondrial and chloroplast functions in Arabidopsis (Arabidopsis thaliana). However, the relative importance of these regulators and whether they act downstream of separate or overlapping signaling cascades is still unclear. Here, we demonstrate that multiple stress-related signaling pathway
The Roles of Mitochondrial Reactive Oxygen Species in Cellular Signaling and Stress Response in Plants
Mitochondria produce ATP via respiratory oxidation of organic acids and transfer of electrons to O2 via the mitochondrial electron transport chain. This process produces reactive oxygen species (ROS) at various rates that can impact respiratory and cellular function, affecting a variety of signaling processes in the cell. Roles in redox signaling, retrograde signaling, plant hormone action, progra
Inactivation of Mitochondrial Complex I Induces the Expression of a Twin Cysteine Protein that Targets and Affects Cytosolic, Chloroplastidic and Mitochondrial Function
At12Cys-1 (At5g64400) and At12Cys-2 (At5g09570) are two closely related isogenes that encode small, twin cysteine proteins, typically located in mitochondria. At12Cys-2 transcript is induced in a variety of mutants with disrupted mitochondrial proteins, but an increase in At12Cys protein is only detected in mutants with reduced mitochondrial complex I abundance. Induction of At12Cys protein in mut
The EF-Hand Ca2+ Binding Protein MICU Choreographs Mitochondrial Ca2+ Dynamics in Arabidopsis
Plant organelle function must constantly adjust to environmental conditions, which requires dynamic coordination. Ca(2+) signaling may play a central role in this process. Free Ca(2+) dynamics are tightly regulated and differ markedly between the cytosol, plastid stroma, and mitochondrial matrix. The mechanistic basis of compartment-specific Ca(2+) dynamics is poorly understood. Here, we studied t