X-Ray Phase-Contrast Imaging with Nanoradian Angular Resolution

We present a new quantitative x-ray phase-contrast imaging method based on the edge illumination principle, which allows achieving unprecedented nanoradian sensitivity. The extremely high angular resolution is demonstrated theoretically and through experimental images obtained at two different synchrotron radiation facilities. The results, achieved at both very high and very low x-ray energies, show that this highly sensitive technique can be efficiently exploited over a very broad range of experimental conditions. This method can open the way to new, previously inaccessible scientific applications in various fields including biology, medicine and materials science

Impact of the Diamond Light Source on research in Earth and environmental sciences: current work and future perspectives.

Diamond Light Source Ltd celebrated its 10th anniversary as a company in December 2012 and has now accepted user experiments for over 5 years. This paper describes the current facilities available at Diamond and future developments that enhance its capacities with respect to the Earth and environmental sciences. A review of relevant research conducted at Diamond thus far is provided. This highlights how synchrotron-based studies have brought about important advances in our understanding of the fundamental parameters controlling highly complex mineral–fluid–microbe interface reactions in the natural environment. This new knowledge not only enhances our understanding of global biogeochemical processes, but also provides the opportunity for interventions to be designed for environmental remediation and beneficial use

Functional impairment of the auditory pathway after perinatal asphyxia and the short-term effect of perinatal propofol anesthesia in lambs

BACKGROUND: Sensorineural hearing loss (SNHL) is a common feature in the postasphyxial syndrome in newborns. Several anesthetic drugs have been proposed to attenuate secondary neuronal injury elicited by hypoxia-ischemia. We hypothesized that propofol anesthesia reduces auditory impairment after perinatal asphyxia in comparison with isoflurane. METHODS: Twenty-three pregnant ewes were randomized to propofol or isoflurane anesthesia and sedation. The lambs underwent in utero umbilical cord occlusion (isoflurane n = 5; propofol n = 7) and were compared with sham-treated animals (isoflurane n = 5; propofol n = 6) at a gestational age of 133 d. For 8 h after delivery by cesarean section, repeated auditory brainstem responses (ABRs) were recorded to obtain hearing thresholds, peak amplitudes, latencies, and interpeak latencies. RESULTS: Significantly elevated mean thresholds, diminished amplitudes, and elevated latencies were observed in the asphyxia group relative to the control group through the observation period. Comparison of anesthetic treatment in the asphyxia group revealed a significantly lower elevation in threshold and less impairment in the ABR amplitudes and latencies during propofol anesthesia as compared with isoflurane anesthesia. CONCLUSION: Our results support the hypothesis that anesthesia with propofol has a preventive effect on the functional changes to the auditory pathway in the event of perinatal asphyxia