Chemical alteration of UO micro-particles in model lung systems.

Uranium dioxide (UO) particles can be released from mines, nuclear fuel manufacturing, reactor accidents, and weapons use. They pose inhalation risks, yet their behavior in the human lung remains poorly understood. This study investigates the long-term chemical alteration and dissolution of µm-sized UO particles in two model lung fluids: Simulated Lung Fluid (SLF) and Artificial Lysosomal Fluid (ALF), representing extracellular and intracellular lung environments, respectively.

Exploiting nanoprobe X-ray techniques for imaging of biomineralisation; chemical, structural and opportunities.

Advances in X-ray nanoprobe beamlines at synchrotrons across the world present exciting opportunities for rich multimodal imaging of biomineral structures and their formation processes. The combination of techniques provides a sensitive probe of both chemistry and structure, making X-ray nanoprobes an important tool for investigating crystallite growth and orientations, interfaces, and assembly of building blocks into hierarchical structures. A discussion of these capabilities is presented with reference to recent examples using a range of nanoprobe imaging techniques for investigating enamel structure, as well as coccolith properties.

The impact of interfacial quality and nanoscale performance disorder on the stability of alloyed perovskite solar cells.

Microscopy provides a proxy for assessing the operation of perovskite solar cells, yet most works in the literature have focused on bare perovskite thin films, missing charge transport and recombination losses present in full devices. Here we demonstrate a multimodal operando microscopy toolkit to measure and spatially correlate nanoscale charge transport losses, recombination losses and chemical composition. By applying this toolkit to the same scan areas of state-of-the-art, alloyed perovskite cells before and after extended operation, we show that devices with the highest macroscopic performance have the lowest initial performance spatial heterogeneity-a crucial link that is missed in conventional microscopy.

An uneven distribution of strontium in the coccolithophore revealed by nanoscale X-ray fluorescence tomography.

Coccolithophores are biogeochemically and ecologically important phytoplankton that produce a composite calcium carbonate-based exoskeleton - the coccosphere - comprised of individual platelets, known as coccoliths. Coccoliths are stunning examples of biomineralization; their formation featuring exceptional control over both biomineral chemistry and shape. Understanding how coccoliths are formed requires information about minor element distribution and chemical environment.

Multi-resolution Correlative Ultrastructural and Chemical Analysis of Carious Enamel by Scanning Microscopy and Tomographic Imaging.

Caries, a major global disease associated with dental enamel demineralization, remains insufficiently understood to devise effective prevention or minimally invasive treatment. Understanding the ultrastructural changes in enamel is hampered by a lack of nanoscale characterization of the chemical spatial distributions within the dental tissue. This leads to the requirement to develop techniques based on various characterization methods.

Differential phase contrast for quantitative imaging and spectro-microscopy at a nanoprobe beamline.

The interaction of a focused X-ray beam with a sample in a scanning probe experiment can provide a variety of information about the interaction volume. In many scanning probe experiments X-ray fluorescence (XRF) is supplemented with measurements of the transmitted or scattered intensity using a pixelated detector. The automated extraction of different signals from an area pixelated detector is described, in particular the methodology for extracting differential phase contrast (DPC) is demonstrated and different processing methods are compared across a range of samples.

The Delta Robot-A long travel nano-positioning stage for scanning x-ray microscopy.

A new stage design concept, the Delta Robot, is presented, which is a parallel kinematic design for scanning x-ray microscopy applications. The stage employs three orthogonal voice coils, which actuate parallelogram flexures. The design has a 3 mm travel range and achieves rms position jitter, integrated from 1 Hz to 1 kHz, of 2.

Explaining the negative impact of workplace incivility on work and non-work outcomes: The roles of negative rumination and organizational support.

Research studies have shown that workplace incivility is associated with numerous negative work and non-work outcomes. The underlying mechanisms explaining why workplace incivility is associated with these outcomes, as well as contextual buffers of these relationships, have received less attention. This study extends workplace incivility research by examining the mediating role of negative rumination as a potential factor undergirding the relationship between experiences of incivility from colleagues at work and detrimental outcomes.

Political identity dissimilarity, workplace incivility, and declines in well-being: A prospective investigation.

The workplace is an environment where individuals have little choice about with whom they interact. As such, employees may find themselves engaged in conversations with coworkers whose political opinions and perspectives are divergent from their own. In the present study, we examined how coworkers' (dis)similarity in political identity is related to the quality of their interpersonal interactions and subsequent well-being.

Solid-State Transformation of Amorphous Calcium Carbonate to Aragonite Captured by CryoTEM.

Early-stage reaction mechanisms for aragonite-promoting systems are relatively unknown compared to the more thermodynamically stable calcium carbonate polymorph, calcite. Using cryoTEM and SEM, the early reaction stages taking place during aragonite formation were identified in a highly supersaturated solution using an alcohol-water solvent, and an overall particle attachment growth mechanism was described for the system. In vitro evidence is provided for the solid-state transformation of amorphous calcium carbonate to aragonite, demonstrating the co-existence of both amorphous and crystalline material within the same aragonite needle.

Competence and performance in causal learning.

The dominant theoretical approach to causal learning postulates the acquisition of associative weights between cues and outcomes. This reduction of causal induction to associative learning implies that learners are insensitive to important characteristics of causality, such as the inherent directionality between causes and effects. An ongoing debate centers on the question of whether causal learning is sensitive to causal directionality (as is postulated by causal-model theory) or whether it neglects this important feature of the physical world (as implied by associationist theories).