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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

Licensed to Kill : Mitochondria, Chloroplasts, and Cell Death

Programmed cell death (PCD) is crucial in plant organogenesis and survival. In this review the involvement of mitochondria and chloroplasts in PCD execution is critically assessed. Recent findings support a central role for mitochondria in PCD, with newly identified components of the mitochondrial electron transport chain (mETC), FOF1 ATP synthase, cardiolipins, and ATPase AtOM66. While chloroplas

The mitochondrial protein import component, TRANSLOCASE OF THE INNER MEMBRANE17-1, plays a role in defining the timing of germination in Arabidopsis

In Arabidopsis (Arabidopsis thaliana), small gene families encode multiple isoforms for many of the components of the mitochondrial protein import apparatus. There are three isoforms of the TRANSLOCASE OF THE INNER MEMBRANE17 (Tim17). Transcriptome analysis indicates that AtTim17-1 is only detectable in dry seed. In this study, two independent transfer DNA insertional mutant lines of tim17-1 exhib

The mitochondrial outer membrane AAA ATPase AtOM66 affects cell death and pathogen resistance in Arabidopsis thaliana

One of the most stress-responsive genes encoding a mitochondrial protein in Arabidopsis (At3g50930) has been annotated as AtBCS1 (cytochrome bc1 synthase 1), but was previously functionally uncharacterised. Here, we show that the protein encoded by At3g50930 is present as a homo-multimeric protein complex on the outer mitochondrial membrane and lacks the BCS1 domain present in yeast and mammalian

A Functional Antagonistic Relationship between Auxin and Mitochondrial Retrograde Signaling Regulates Alternative Oxidase1a Expression in Arabidopsis

The perception and integration of stress stimuli with that of mitochondrion function are important during periods of perturbed cellular homeostasis. In a continuous effort to delineate these mitochondrial/stress-interacting networks, forward genetic screens using the mitochondrial stress response marker alternative oxidase 1a (AOX1a) provide a useful molecular tool to identify and characterize reg

Environmental aspects of coal mine drainage: a regional study of Moatize in Mozambique

Mozambique is one of the largest coal producers in Africa. Extraction of the coal is carried out in the Moatize district of the Tete province in the center of the country. A surface mining technique is used to extract the coal below ground level. During mining activities, sulfide minerals, which are commonly associated with coal, are exposed to oxygen and water, leading to the generation of acid m

A comparative analysis of human and mouse islet G-protein coupled receptor expression

G-protein coupled receptors (GPCRs) are essential for islet function, but most studies use rodent islets due to limited human islet availability. We have systematically compared the GPCR mRNA expression in human and mouse islets to determine to what extent mouse islets can be used as surrogates for human islets to study islet GPCR function, and we have identified species-specific expression of sev

Stages of change in audiology : comparison of three self-assessment measures

Objective: In a clinical setting, theories of health behaviour change could help audiologists and other hearing health care professionals understand the barriers that prevent people with hearing problems to seek audiological help. The transtheoretical (stages of change) model of health behaviour change is one of these theories. It describes a person’s journey towards health behaviour change (e.g.