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Since its invention in the mid 1980s atomic force microscopy has revolutionised the way in which surfaces can be imaged. Close to atomic resolution has been achieved for some materials and numerous images of molecules on surfaces have been recorded. Atomic force microscopy has also been of benefit to biology where protein molecules on surfaces have been studied and even whole cells have been investigated. Here we report a study of red blood cells which have been imaged in a physiological medium. At high resolution, the underlying cytoskeleton of the blood cell has been resolved and flaws in the cytoskeleton structure may be observed. Comparison of the normal 'doughnut' shaped cells with swollen cells has been undertaken. Differences in both the global properties of the cells and in the local features in cytoskeleton structure have been observed.

Graphitic carbon nitride (gCN­(H)) is a semiconductor with high mechanical and thermal stability which provides good dispersion of metal particles. As it is resistant to corrosion, it constitutes an alternative to carbon black as a catalyst support in polymer electrolyte membrane fuel cells (PEMFCs), e.g., in alcohol oxidation reactions. In this research work, gCN (H)-supported catalyst has been characterized by spectroscopic (UV–vis, IR, Raman) and microscopy techniques (SEM, TEM, AFM) in order to gain deeper understanding of the relationship between material properties and electrochemical activity. Ni-doped graphitic carbon nitride (Ni/gCN­(H)) was tested in electrooxidation of ethanol demonstrating comparatively high peak current density and interesting photocatalytic properties. The obtained results suggest that the improvement of the activity and selectivity of Ni-modified gCN­(H) can be related to the chemical and electronic material modification, while the sample morphology and topology is preserved. Metal–support interactions account for the high photocatalytic activity, superior to that of the Pt counterpart.

Indanthrone, an old, insoluble dye can be converted into a solution processable, self-assembling and electroluminescent organic semiconductor, namely tetraoctyloxydinaptho[2,3-a:2 0 ,3 0 -h]phenazine (P-C8), in a simple one-pot process consisting of the reduction of the carbonyl group by sodium dithionite followed by the substitution with solubility inducing groups under phase transfer catalysis conditions.

Amyloid β, Aβ(1–42), is a component of senile plaques present in the brain of Alzheimer’s disease patients and one of the main suspects responsible for pathological consequences of the disease. Herein, we directly visualize the Aβ activity toward a brain-like model membrane and demonstrate that this activity strongly depends on the Aβ oligomer size. PeakForce quantitative nanomechanical mapping mode of atomic force microscopy imaging revealed that the interaction of large-size (LS) Aβ oligomers, corresponding to high-molecular-weight Aβ oligomers, with the brain total lipid extract (BTLE) membrane resulted in accelerated Aβ fibrillogenesis on the membrane surface. Importantly, the fibrillogenesis did not affect integrity of the membrane. In contrast, small-size (SS) Aβ oligomers, corresponding to low-molecular-weight Aβ oligomers, created pores and then disintegrated the BTLE membrane. Both forms of the Aβ oligomers changed nanomechanical properties of the membrane by decreasing its Young’s modulus by ∼45%. Our results demonstrated that both forms of Aβ oligomers induce the neurotoxic effect on the brain cells but their action toward the membrane differs significantly.

IntroductionChronic diseases such as cancer have a strong influence on both physical health and quality of life, which together comprise the concept of health-related quality of life (HRQoL) – in other words, the complete state of physical, social, and psychological functioning. Herein, we review the literature on the theory of HRQoL in relation to oncological diseases.Material and methodsA literature search of English-language publications that included an analysis of the conceptual models of HRQoL was performed using PubMed. The data were screened and synthesized by all authors and relevant papers were selected.ResultsWe outline the theoretical models most often used to conceptualize HRQoL, including the Centre for Health Promotion model from the University of Toronto, the conceptual model of Wilson and Cleary and the contextual model of Ashing-Giwa formulated specifically for cancer patients.ConclusionsUnderstanding the theoretical basis of HRQoL is indispensable for valid research in this area.

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