Impact of instrumentation in lumbar spinal fusion in elderly patients

Background and purpose An increasing number of lumbar fusions are performed using allograft to avoid donor-site pain. In elderly patients, fusion potential is reduced and the patient may need supplementary stability to achieve a solid fusion if allograft is used. We investigated the effect of instrumentation in lumbar spinal fusion performed with fresh frozen allograft in elderly patients

Real-time observation of multiexcitonic states in ultrafast singlet fission using coherent 2D electronic spectroscopy.

Singlet fission is the spin-allowed conversion of a spin-singlet exciton into a pair of spin-triplet excitons residing on neighbouring molecules. To rationalize this phenomenon, a multiexcitonic spin-zero triplet-pair state has been hypothesized as an intermediate in singlet fission. However, the nature of the intermediate states and the underlying mechanism of ultrafast fission have not been elucidated experimentally. Here, we study a series of pentacene derivatives using ultrafast two-dimensional electronic spectroscopy and unravel the origin of the states involved in fission. Our data reveal the crucial role of vibrational degrees of freedom coupled to electronic excitations that facilitate the mixing of multiexcitonic states with singlet excitons. The resulting manifold of vibronic states drives sub-100 fs fission with unity efficiency. Our results provide a framework for understanding singlet fission and show how the formation of vibronic manifolds with a high density of states facilitates fast and efficient electronic processes in molecular systems.This is the author accepted manuscript. The final version is available from NPG via http://dx.doi.org/10.1038/nchem.237

Person-Related Protective and Vulnerability Factors of Psychopathology Symptoms in Non-Clinical Adolescents

Psychopathology in youths is thought to originate from a dynamic interplay of a variety of protective and vulnerability factors. In this study, a large multi-ethnic sample of non-clinical adolescents (N = 376) completed questionnaires for measuring a wide range of person-related protective and vulnerability factors as well as psychopathology symptoms, in order to explore (a) the relations among various protective and vulnerability factors, and (b) the unique contributions of these protective and vulnerability factors to different types of psychological problems. Results indicated that the overlap among protective and vulnerability factors was quite modest. Further, it was found that factors clustered in theoretically meaningful components reflecting protection, vulnerability, and more specific aspects of coping and social support. Finally, data indicated that each type of psychopathology symptoms was associated with a typical set of protective and vulnerability factors. Although these results should be interpreted with caution because of the cross-sectional nature of the study, they may nevertheless guide future research exploring multifactorial models of psychopathology in youths

Technical design of the phase I Mu3e experiment

The Mu3e experiment aims to find or exclude the lepton flavour violating decay μ→eee at branching fractions above 10−16. A first phase of the experiment using an existing beamline at the Paul Scherrer Institute (PSI) is designed to reach a single event sensitivity of 2⋅10−15. We present an overview of all aspects of the technical design and expected performance of the phase I Mu3e detector. The high rate of up to 108 muon decays per second and the low momenta of the decay electrons and positrons pose a unique set of challenges, which we tackle using an ultra thin tracking detector based on high-voltage monolithic active pixel sensors combined with scintillating fibres and tiles for precise timing measurements