Pressure-induced change of d-d luminescence energies, vibronic structure and band intensities in transition metal complexes

The effects of hydrostatic pressure on the luminescence spectra of tetragonal transition metal complexes with nondegenerate electronic ground states are analyzed quantitatively by means of models based on potential energy surfaces defined along normal coordinates. Pressure-induced changes of intensity distributions within vibronic progressions, band maxima, electronic origins and relaxation rates are discussed for metal-oxo complexes of rhenium(V) and molybdenum(IV) (d2 electron configuration) and for square-planar complexes of palladium(II) and platinum(II) (d8 electron configuration)

The application of mHealth to mental health: opportunities and challenges

Recent advances in smartphones and wearable biosensors enable the gathering of ‘real-time’ psychological, behavioural and physiological data, in increasingly precise and unobtrusive ways. It is therefore now possible to collect moment-to-moment information about an individuals’ moods, cognitions and activities, as well as automated data about their whereabouts, behaviour and physiological states. In this paper, we discuss the potential of these new mobile digital technologies for transforming mental health research and clinical practice. By drawing on a recent research project, we illustrate how traditional boundaries between research and clinical practice are becoming increasingly blurred and how in turn, this is leading to exciting new developments in the assessment and management of common mental disorders. The potential risks and key challenges associated with applying mobile technology to mental health are also discussed

Modeling the human bone marrow niche in mice: From host bone marrow engraftment to bioengineering approaches

Xenotransplantation of patient-derived samples in mouse models has been instrumental in depicting the role of hematopoietic stem and progenitor cells in the establishment as well as progression of hematological malignancies. The foundations for this field of research have been based on the development of immunodeficient mouse models, which provide normal and malignant human hematopoietic cells with a supportive microenvironment. Immunosuppressed and genetically modified mice expressing human growth factors were key milestones in patient-derived xenograft (PDX) models, highlighting the importance of developing humanized microenvironments. The latest major improvement has been the use of human bone marrow (BM) niche-forming cells to generate human-mouse chimeric BM tissues in PDXs, which can shed light on the interactions between human stroma and hematopoietic cells. Here, we summarize the methods used for human hematopoietic cell xenotransplantation and their milestones and review the latest approaches in generating humanized BM tissues in mice to study human normal and malignant hematopoiesis

Enhanced visible light absorption in layered Cs_{3}Bi_{2}Br_+{9} through mixed-valence Sn(II)/Sn(IV) doping

Lead-free halides with perovskite-related structures, such as the vacancy-ordered perovskite Cs_{3}Bi_{2}Br_{9}, are of interest for photovoltaic and optoelectronic applications. We find that addition of SnBr2 to the solution-phase synthesis of Cs_{3}Bi_{2}Br_{9} leads to substitution of up to 7% of the Bi(III) ions by equal quantities of Sn(II) and Sn(IV). The nature of the substitutional defects was studied by X-ray diffraction, {133}^Cs and {119}^Sn solid state NMR, X-ray photoelectron spectroscopy and density functional theory calculations. The resulting mixed-valence compounds show intense visible and near infrared absorption due to intervalence charge transfer, as well as electronic transitions to and from localised Sn-based states within the band gap. Sn(II) and Sn(IV) defects preferentially occupy neighbouring B-cation sites, forming a double-substitution complex. Unusually for a Sn(II) compound, the material shows minimal changes in optical and structural properties after 12 months storage in air. Our calculations suggest the stabilisation of Sn(II) within the double substitution complex contributes to this unusual stability. These results expand upon research on inorganic mixed-valent halides to a new, layered structure, and offer insights into the tuning, doping mechanisms, and structure–property relationships of lead-free vacancy-ordered perovskite structures

Synthesis of Carboxymethyl Starch for increasing drilling mud quality in drilling oil and gas wells

This paper describes the impact of carboxymethyl starch preparation conditions on physicochemical properties of polysaccharide reagent, widely used as fluid loss reducing agent in drilling mud. Variation of the main parameters of carboxymethylation is researched in the experiment. The following conditions such as temperature and reaction time, amount of water, as well as ratio of NaOH to monochloracetic acid define the characteristics of carboxymethyl starch. The degree of substitution is defined for polysaccharides, as well as the characteristics of samples have been studied by infrared spectroscopy. Rheological characteristics and fluid loss indicator have been investigated to study the impact of the reagents on drilling mud quality

MP3 - A meteorology and physical properties package to explore air-sea interaction on Titan

The exchange of mass, heat and momentum at the air:sea interface are profound influences on the terrestrial environment, affecting the intensity of hurricanes, the size of waves and lake-effect precipitation. Titan presents us with an opportunity to study these processes in a novel physical context, with a different sea, atmosphere and gravity. The MP3 instrument, under development for the proposed Discovery mission TiME (Titan Mare Explorer [1,2]) is an integrated suite of small, simple sensors that combines the function of traditional meteorology packages with liquid physical properties and depth-sounding : these latter functions follow the concept of - and indeed use spare elements from - the Huygens Surface Science Package (SSP,[3]). However, unlike Huygens’ brief and dynamic 3 hours of measurement, in TiME’s 6-Titan-day (96 Earth day) nominal mission enabled by radioisotope power, MP3 will have an unprecedented long-term measurement opportunity in one of the most evocative environments in the solar system, Titan’s sea Ligeia Mare