Quaternary ammonium compounds (QACs) or quats are a large class of antimicrobial chemicals used in households and institutions as sanitizers and disinfectants. These chemicals are utilized as food ...processing sanitizers, algicides, in the process of water treatment, and preservatives in cosmetics. The aim of this study was to determine an Adverse Outcome Pathway (AOP) whereby two widely used QACs, alkyl dimethyl benzyl ammonium chloride (ADBAC) and didecyl dimethyl ammonium chloride (DDAC), may result in respiratory tract and gastrointestinal tract effects. When inhaled or ingested, these QACs are incorporated into the epithelial cell membrane at the point of contact. With sufficient dosage, the epithelial membrane is disrupted, reducing its fluidity, and releasing cellular contents. Further, ADBAC and DDAC might disrupt mitochondrial functions leading to decreased ATP production. Both events might lead to cell death, either attributed to direct lysis, necrosis, or apoptosis. Pro-inflammatory mediators are recruited to the tissue, inducing inflammation, edema, and excess mucus production. The primary tissue-level adverse outcome is epithelial degeneration and dysplasia. Most important, no apparent metabolism or distribution is involved in QAC action. Based upon this knowledge, it is suggested to replace default Uncertainty Factors for risk assessments with a set of Data Derived Extrapolation Factors.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
Despite a century of professional development in youth ministry, the American church continues to face generational attrition. This article explores this paradox, employing practical theology to ...scrutinise the historical praxis and philosophies shaping 20th-century youth ministry. I have taken Nel’s work on inclusive missional ecclesiology as my basic point of departure, analysing four interconnected ‘texts’: Ecclesiological perspective, a historical review of youth ministry evolution, adolescents’ developmental locus within congregations, and a qualitative study featuring interviews with members from seven American churches involved in youth ministry. The investigation highlights the necessity for a paradigm shift in youth ministry from an exclusive programme to a more inclusive missional approach. It urges recognising adolescents as equals in congregational life, fostering an environment that not only retains but also nurtures them as indispensable community members. By adhering to this reformed vision, the church can address the persistent crisis of generational attrition effectively, encouraging the collaborative growth of the American church with the active participation of its adolescent members. It suggests a path forward that sees youth not as future church, but active contributors to the contemporary church ecosystem.Intradisciplinary and/or interdisciplinary implications: This research guides churches in considering the theological, sociological, and developmental implications of adolescent inclusion through the lens of missional ecclesiology, suggesting adolescent inclusion is critical to contextual missional praxis.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Analysis of spontaneous reports of adverse events is an important source of information that can be used to improve consumer products. Various agencies have adverse event reporting requirements and ...many companies collect such data directly from consumers. Nonetheless, a universal framework is absent that identifies and evaluates spontaneously reported adverse events, and, most important, assesses the potential association between exposure and adverse events. We are presenting a three-part framework: Phase I - Intake and Documentation of Original Incidents; Phase II – In Depth Review and Follow-up of Phase I Incidents (enhanced, tailored questionnaire); Phase III - Association Assessment. The basis for scoring the strength of association between exposure and adverse events requires assessment of standard factors of association including: temporality; biological, physiological, or pharmacological plausibility; results of de-challenge; results of re-challenge; and consideration of confounding factors. Scores tied to the answers to these questions are totaled for each incident to determine the strength of association between exposure and reported adverse event. We propose that consumer product companies come together to adopt such an association assessment framework to improve adverse event management, obtain maximum value from the data obtained, and use the knowledge derived to improve overall product safety for consumers.
•Investigation of adverse events from consumer product exposure is essential.•An enhanced interview questionnaire can be tailored to effects of most interest.•Follow-up may enable scoring of association between exposure and adverse event.•Scoring of association will help identify products in need of risk management.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Forest soils are under‐represented throughout the existing soil hydraulic databases. Classical measurement methods for the hydraulic soil characteristics are very time‐consuming and are not suited ...for routine application in the course of soil survey. We are presently engaged in establishing a database of the hydraulic properties of forest soils using multistep outflow experiments together with an inverse optimization of the Mualem/van Genuchten parameters from the tension and outflow measurements. The lower boundary in the multistep outflow experiments was modified such that, firstly, the experiment can be conducted as fast as possible and hence can be incorporated in the framework of routine soil monitoring. Secondly, the experimental design should be identical for a large texture range and therefore allow for a statistical comparison of the hydraulic properties of a broad variety of soils. Thirdly, the experiments must be designed such that they yield sufficient measurements for a unique and stable inverse parameter estimation. The inverse parameter estimates of the presently available 141 multistep outflow experiments were compared with predictions of two pedotransfer functions. For most soil samples, the PTF predictions differed highly from the MSO estimates. Reasons for this are, among others, insufficient hydraulic measurements included in the datasets used for establishing the PTFs and, specifically, insufficient information on water retention/conductivity in the range of the air entry value. Here, the MSO experiments can provide much more detailed information on the water retention and conductivity curves because they yield measurements over a continuous pressure range and are conducted such that the pressure range of the air entry value is covered by sufficient tension and outflow measurements. The presented research aims to: (i) introduce the measurement of soil hydraulic properties in an ongoing soil monitoring campaign, (ii) complement existing soil hydraulic databases with data from forest soils, and (iii) enhance the reliability of soil hydraulic databases through a standardization of the measuring approaches.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
ABSTRACT During 2010 August a series of solar particle events was observed by the two STEREO spacecraft as well as near-Earth spacecraft. The events, occurring on August 7, 14, and 18, originated ...from active regions 11093 and 11099. We combine in situ and remote-sensing observations with predictions from our model of three-dimensional anisotropic particle propagation in order to investigate the physical processes that caused the large angular spreads of energetic electrons during these events. In particular, we address the effects of the lateral transport of the electrons in the solar corona that is due to diffusion perpendicular to the average magnetic field in the interplanetary medium. We also study the influence of two coronal mass ejections and associated shock waves on the electron propagation, and a possible time variation of the transport conditions during the above period. For the August 18 event we also utilize electron observations from the MESSENGER spacecraft at a distance of 0.31 au from the Sun for an attempt to separate between radial and longitudinal dependencies in the transport process. Our modelings show that the parallel and perpendicular diffusion mean free paths of electrons can vary significantly not only as a function of the radial distance, but also of the heliospheric longitude. Normalized to a distance of 1 au, we derive values of λ in the range of 0.15-0.6 au, and values of λ in the range of 0.005-0.01 au. We discuss how our results relate to various theoretical models for perpendicular diffusion, and whether there might be a functional relationship between the perpendicular and the parallel mean free path.
Context. In February 2011, the two STEREO spacecrafts reached a separation of 180 degrees in longitude, offering a complete view of the Sun for the first time ever. When the full Sun surface is ...visible, source active regions of solar energetic particle (SEP) events can be identified unambiguously. STEREO, in combination with near-Earth observatories such as ACE or SOHO, provides three well separated viewpoints, which build an unprecedented platform from which to investigate the longitudinal variations of SEP events. Aims. We show an ensemble of SEP events that were observed between 2009 and mid-2013 by at least two spacecrafts and show a remarkably wide particle spread in longitude (wide-spread events). The main selection criterion for these events was a longitudinal separation of at least 80 degrees between active region and spacecraft magnetic footpoint for the widest separated spacecraft. We investigate the events statistically in terms of peak intensities, onset delays, and rise times, and determine the spread of the longitudinal events, which is the range filled by SEPs during the events. Energetic electron anisotropies are investigated to distinguish the source and transport mechanisms that lead to the observed wide particle spreads. Methods. According to the anisotropy distributions, we divided the events into three classes depending on different source and transport scenarios. One potential mechanism for wide-spread events is efficient perpendicular transport in the interplanetary medium that competes with another scenario, which is a wide particle spread that occurs close to the Sun. In the latter case, the observations at 1 AU during the early phase of the events are expected to show significant anisotropies because of the wide injection range at the Sun and particle-focusing during the outward propagation, while in the first case only low anisotropies are anticipated. Results. We find events for both of these scenarios in our sample that match the expected observations and even different events that do not agree with the scenarios. We conclude that probably both an extended source region at the Sun and perpendicular transport in the interplanetary medium are involved for most of these wide-spread events.
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FMFMET, NUK, UL, UM, UPUK
The 1998 September 9 solar particle event was a super(3)He-rich solar particle event that showed a strong increase of Fe ionization states in the energy range below 1 MeV nucleon super(-1). We have ...investigated this event by fitting Wind and ACE observations using a model of acceleration and stripping near the Sun, followed by particle transport in the interplanetary medium taking into account particle focusing, pitch-angle scattering, adiabatic deceleration, and convection. The simulation provides a reconstruction of the injection function of the energetic particles released from the Sun and their time, energy, and charge dependence. We find that electrons and Fe ions are injected almost impulsively, whereas the injection of protons takes place on a much longer timescale or even consists of two distinct injection processes. We are able to obtain good overall fits to the observations. This suggests that our model can be used to obtain information about the conditions in the acceleration region such as density, temperature, and the timescales of the acceleration process, if sufficiently accurate modeling of the particle transport in the solar wind is possible.
We introduce a simplified method to calculate the cross sections and rates of ionization and recombination of accelerated ions with arbitrary nuclear charge Z and atomic mass number A. Calculations ...of equilibrium and nonequilibrium charge states of the element Tellurium (Te, image) are presented for the first time. The validity of the proposed method is demonstrated by showing that predictions for Si and Fe are in agreement at energies characteristic for energetic (>=0.15 MeV nucleon super(-1)) ultraheavy ions with the results of a more sophisticated model. We find that while the charge states for te come out higher than those for Fe under similar conditions, the image values for te fall consistently below those for Fe over the entire energy range and under all comparable conditions, thus extending the trend in image that is observed when going to higher mass elements. Implications of our results for the observed enrichments of ultraheavy ions in solar energetic particle events are discussed.
ABSTRACT Many shock acceleration theories deal with gyrophase-averaged particle distributions that depend only on the energy and pitch angle of the particles. Diffusive shock acceleration includes ...shock crossing as a necessary component. As long as the shock width is much smaller than the mean free path of a particle, the crossing is governed by the macroscopic fields inside the transition layer. The dynamics of high-energy particles in these fields is non-adiabatic and gyrophase dependent. The magnetic moment is not conserved in a wide range of shock angles, nor is the condition of reflection determined by the magnetic bottle relation. Instead, for a pitch angle and unknown gyrophase of an incident particle there is a finite probability of reflection. This probability varies between zero and unity in a wide range of pitch angles. In this work we investigate how the matching conditions at the shock front could be modified with the gyrophase dependence taken into account, e.g., in the form of the scattering probabilities.
We investigate multi-spacecraft observations of the 17 January 2010 solar energetic particle event. Energetic electrons and protons have been observed over a remarkable large longitudinal range at ...the two STEREO spacecraft and SOHO, suggesting a longitudinal spread of nearly 360 degrees at 1 AU. The flaring active region, which was on the backside of the Sun as seen from Earth, was separated by more than 100 degrees in longitude from the magnetic footpoints of each of the three spacecraft. The event is characterized by strongly delayed energetic particle onsets with respect to the flare and only small or no anisotropies in the intensity measurements at all three locations. The presence of a coronal shock is evidenced by the observation of a type II radio burst from the Earth and STEREO-B. In order to describe the observations in terms of particle transport in the interplanetary medium, including perpendicular diffusion, a 1D model describing the propagation along a magnetic field line (model 1) (Dröge,
Astrophys. J
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589
, 1027 – 1039,
2003
) and the 3D propagation model (model 2) by Dröge
et al
. (
Astrophys. J
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709
, 912 – 919,
2010
) including perpendicular diffusion in the interplanetary medium have been applied. While both models are capable of reproducing the observations, model 1 requires injection functions at the Sun of several hours. Model 2, which includes lateral transport in the solar wind, reveals high values for the ratio of perpendicular to parallel diffusion. Because we do not find evidence for unusual long injection functions at the Sun, we favor a scenario with strong perpendicular transport in the interplanetary medium as an explanation for the observations.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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