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Abstract: This study aimed at the development of improved drugs against human osteosarcoma, which is the most common primary bone tumor in children and teenagers with a low prognosis available treatment. New insights into the impact of an unconventional Pd(II) anticancer agent on human osteosarcoma cells were obtained by synchrotron-based infrared microspectroscopy (SR-microFTIR) and quasi-elastic neutron scattering (QENS) experiments from its effect on the cellular metabolism to its influence on intracellular water which can be regarded as a potential secondary pharmacological target. Specific infrared biomarkers of drug action were identified, enabling a molecular-level description of variations in cellular biochemistry upon drug exposure. The main changes were detected on the protein and lipid cellular components, namely on the ration of unsaturated-to-saturated fatty acids. QENS revealed a reduced water mobility within the cytoplasm for drug-treated cells, coupled to a disruption of the hydration layers of biomolecules. Additionally, the chemical and dynamical profiles of osteoscarcoma cells were compared to metastatic breast cancer, revealing distinct dissimilarities that may influence drug activity.

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Abstract: The formation and distribution of metal soaps produced as a result of the reactivity and aging of the materials in a fifteenth-century egg tempera and oil paintings on wood are presented. The painting technique involves the application of several paint layers over a ground using, sometimes in the same paint layer sequence, drying oil and egg yolk binders. We show, with a selection of examples, how the use of thin sections and a combination of various micro-sensitive analytical techniques is adequate to obtain the high-quality data necessary for the unambiguous identification of metal soaps and metal oxalates as well as their distribution in the paint layers. The techniques include micro infrared spectroscopy (μSR-FTIR) and micro X-ray diffraction (μSR-XRD) with synchrotron radiation, optical microscopy (OM), and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS). The data obtained sheds light about the underlying reaction and aging mechanisms happening in each paint layer and among them. This helps to define the state of conservation of the artworks.

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Abstract: A catalytic system based on OX-1 metal-organic framework nanosheets is reported, incorporating catalytically active palladium (Pd) species. The Pd@OX-1 guest@host system is rapidly synthesised via a facile single-pot supramolecular assembly method, with the possibility of controlling the Pd loading. The structures of the re-sulting framework and of the active Pd species before and after catalytic reactions are studied in detail using a wide variety of techniques including synchrotron radiation infrared spectroscopy, inelastic neutron scattering and X-ray absorption spectroscopy. Crystals of the resulting Pd@OX-1 composite material contain predomi-nantly atomic and small cluster Pd species, which selectively reside on benzene rings of the benzenedicarbox-ylate (BDC) linkers. The composites are shown to efficiently catalyse the Suzuki coupling and Heck arylation reactions under a variety of conditions. Pd@OX-1 further shows potential to be recycled for at least five cycles of each reaction as well as an ability to recapture active Pd species during both catalytic reactions.

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Abstract: The design and characterisation of rectifying terahertz detectors, based on InGaAs zero-bias Schottky diodes, is reported. These uncooled devices offer a spectral detection range from tens of GHz to above 3 THz, high response speed, and the prospect of low cost for mass production and arrayed implementation. We describe the airbridged semiconductor devices, their incorporation into waveguide mounts and quasi-optical substrate lens / planar antenna structures. Noise equivalent powers of 5 pW/Hz1/2 at 100 GHz, increasing to 50 pW/Hz1/2 at 300 GHz been achieved, along with rise and fall times of tens of picoseconds. We shall discuss examples of the use of the detectors: characterising a picosecond transistor-based source, spectrally narrow and broad band sources in the laboratory and coherent THz synchrotron radiation in the range 0.15 to 1.4 THz at the MIRIAM beamline B22 on the Diamond Light Source. The latter radiation was emitted from bunches of electrons circulating in the Diamond storage ring operating in THz-dedicated low-alpha mode. Spectral information on coherent synchrotron radiation originating from a single bunch of electrons is obtained, as well as the usefulness of this for spectroscopy, is evaluated.

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Abstract: Fourier transform infrared spectroscopy (FTIR) and microscopy (FT-IRMS) are well-established as tools for the study of biological cells. Studies of chemically-fixed cells using infrared (IR) have been able to yield significant information regarding cell morphology, disease development and drug-cell interactions. However, such studies are limited by fixation effects which introduce a range of spectral variations, limiting the interpretation of IR spectra of fixed cells. It is therefore desirable to study living cells in real time, particularly as cells are undergoing response to an external stimulus. This does, however, present a number of challenges. Maintaining live cells requires an aqueous sample environment. Water is, however, a very strong absorber of IR light, producing a spectrum which dwarfs the biochemical signals in the sample and makes the extraction of good-quality spectra with high signal-to-noise (S/N) extremely challenging. The brilliance of synchrotron radiation (SR), combined with development of an in-house water correction procedure performing a least-squares fit with a (Matrigel) reference spectrum, has been able to generate high-quality spectra while retaining a sufficient level of spectral detail to analyse relative subtle biochemical changes. Wildtype and drug-resistant strains of renal cell carcinoma (RCC) have been treated with different chemotherapy agents and formalin-fixed. Analysis of fixed, dried samples using both single-point SR IR microscopy and bench-top focal plane array (FPA) imaging has identified spectral features linked to efflux of similar drug-resistance mechanisms, opening the possibility of being able to identify drug resistance in the early stages of treatment. These results were able to be replicated using fixed cells suspended in phosphate-buffered saline (PBS), providing validation of the water correction algorithm. Two live cell studies were performed in a static aqueous sample holder. K562 acute myeloid leukaemia (AML) cells were treated with two novel chemotherapy agents, and differences were identified in the resulting spectra that could be directly linked to the mode of action of the two compounds. This analysis made use of DNA bands that are only accessible when measuring hydrated cells. The second study used a wildtype and drug-resistant strain of PEO1 ovarian cancer cells, and analysed their response to a novel agent, showing differences in the measured spectra between wildtype and resistance samples. Static-mode live cell studies have been able to provide significant information, but are limited by the survival time of the samples. A customised commercial liquid sample holder has undergone simple and cost-effective modifications to produce a dynamic flow system for live cell measurements, potentially up to and beyond 24 hours. This includes the novel implementation of a hydrophobic barrier to direct and control flow. Trypan blue staining has confirmed cell viability up to at least 24 hours, and two biological studies have been performed to demonstrate different properties of the system. Measuring samples at different temperatures has proved that the system is capable of inducing and simultaneously measuring cellular changes, while a study of deuterated palmitic acid uptake has shown that a sample can be maintained for long enough to acquire spectra of a large number of cells.