Transition metal dichalcogenides have attracted research interest over the last few decades due to their interesting structural chemistry, unusual electronic properties, rich intercalation chemistry and wide spectrum of potential applications. Despite the fact that the majority of related research focuses on semiconducting transition-metal dichalcogenides (for example, MoS2), recently discovered unexpected properties of WTe2 are provoking strong interest in semimetallic transition metal dichalcogenides featuring large magnetoresistance, pressure-driven superconductivity and Weyl semimetal states. We investigate the sister compound of WTe2, MoTe2, predicted to be a Weyl semimetal and a quantum spin Hall insulator in bulk and monolayer form, respectively. We find that bulk MoTe2 exhibits superconductivity with a transition temperature of 0.10 K. Application of external pressure dramatically enhances the transition temperature up to maximum value of 8.2 K at 11.7 GPa. The observed dome-shaped superconductivity phase diagram provides insights into the interplay between superconductivity and topological physics.

LaMnO(3) was studied by synchrotron x-ray diffraction, optical spectroscopies, and transport measurements under pressures up to 40 GPa. The cooperative Jahn-Teller (JT) distortion is continuously reduced with increasing pressure. There is strong indication that the JT effect and the concomitant orbital order are completely suppressed above 18 GPa. The system, however, retains its insulating state to approximately 32 GPa, where it undergoes a bandwidth-driven insulator-metal transition. Delocalization of electron states, which suppresses the JT effect but is insufficient to make the system metallic, appears to be a key feature of LaMnO(3) at 20-30 GPa.

Biominerals are impressive composite materials because of their complex organization and perfect adaptation to the demands of living organisms. Structure and development of human teeth are compared to similar composite systems that develop in vitro under biomimetic conditions without the controlling influence of cells.

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Rock and ice climbing are widely considered to be 'high-risk' sporting activities that are associated with a high incidence of severe injury and even death, compared with more mainstream sports. However, objective scientific data to support this perception are questionable. Accordingly, >400 sport-specific injury studies were analysed and compared by quantifying the injury incidence and objectively grading the injury severity (using the National Advisory Committee for Aeronautics score) per 1000 hours of sporting participation. Fatalities were also analysed. The analysis revealed that fatalities occurred in all sports, but it was not always clear whether the sport itself or pre-existing health conditions contributed or caused the deaths. Bouldering (ropeless climbing to low heights), sport climbing (mostly bolt protected lead climbing with little objective danger) and indoor climbing (climbing indoors on artificial rock structures), showed a small injury rate, minor injury severity and few fatalities. As more objective/external dangers exist for alpine and ice climbing, the injury rate, injury severity and fatality were all higher. Overall, climbing sports had a lower injury incidence and severity score than many popular sports, including basketball, sailing or soccer; indoor climbing ranked the lowest in terms of injuries of all sports assessed. Nevertheless, a fatality risk remains, especially in alpine and ice climbing. In the absence of a standard definition for a 'high-risk' sport, categorizing climbing as a high-risk sport was found to be either subjective or dependent on the definition used. In conclusion, this analysis showed that retrospective data on sport-specific injuries and fatalities are not reported in a standardized manner. To improve preventative injury measures for climbing sports, it is recommended that a standardized, robust and comprehensive sport-specific scoring model should be developed to report and fully evaluate the injury risk, severity of injuries and fatality risk in climbing sports.

We present Raman spectra of numerous icosahedral boron-rich solids having the structure of α-rhombohedral, β-rhombohedral, α-tetragonal, β-tetragonal, YB 66 , orthorhombic or amorphous boron. The spectra were newly measured and, in some cases, compared with reported data and discussed. We emphasize the importance of a high signal-to-noise ratio in the Raman spectra for detecting weak effects evoked by the modification of compounds, accommodation of interstitial atoms and other structural defects. Vibrations of the icosahedra, occurring in all the spectra, are interpreted using the description of modes in α-rhombohedral boron by Beckel et al. The Raman spectrum of boron carbide is largely clarified. Relative intra-and inter-icosahedral bonding forces are estimated for the different structural groups and for vanadium-doped β-rhombohedral boron. The validity of Badger's rule is demonstrated for the force constants of inter-icosahedral B-B bonds, whereas the agreement is less satisfactory for the intra-icosahedral B-B bonds.

InGaN quantum wells were grown by metal organic vapor-phase epitaxy on polar (0 0 0 1), nonpolar (1 0 1 0) and on semipolar (1 0 1 2), (1 1 2 2), (1 0 1 1) as well as (2 0 2 1) oriented GaN substrates. The room-temperature photoluminescence (PL) and electroluminescence (EL) emission energies for quantum wells grown on different crystal orientations show large variations of up to 600 meV. The following order of the emission energy was found throughout the entire range of growth temperatures: (1 0 1 1) < (1 1 2 2) = (0 0 0 1) < (2 0 2 1) < (1 0 1 0) = (1 0 1 2). In order to differentiate between the effects of strain, quantum-confined stark effect (QCSE) and indium incorporation the experimental data were compared to k.p theory-based calculations for differently oriented InGaN QWs. The major contribution to the shift between (1 0 1 0) and (0 0 0 1) InGaN quantum wells can be attributed to the QCSE. The redshift between (1 0 1 0) and the semipolar (1 0 1 2) and (2 0 2 1) QWs can be attributed to shear and anisotropic strain affecting the valence band structure. Finally, for (1 1 2 2) and (1 0 1 1) the emission energy shift could be attributed to a significantly higher indium incorporation efficiency.