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A vast body of literature exists showing functional and structural dysfunction within the brains of patients with disorders of consciousness. However, the function (fluorodeoxyglucose FDG-PET metabolism)-structure (MRI-diffusion-weighted images; DWI) relationship and how it is affected in severely brain injured patients remains ill-defined. FDG-PET and MRI-DWI in 25 severely brain injured patients (19 Disorders of Consciousness of which 7 unresponsive wakefulness syndrome, 12 minimally conscious; 6 emergence from minimally conscious state) and 25 healthy control subjects were acquired here. Default mode network (DMN) function-structure connectivity was assessed by fractional anisotropy (FA) and metabolic standardized uptake value (SUV). As expected, a profound decline in regional metabolism and white matter integrity was found in patients as compared with healthy subjects. Furthermore, a function-structure relationship was present in brain-damaged patients between functional metabolism of inferior-parietal, precuneus, and frontal regions and structural integrity of the frontal-inferiorparietal, precuneus-inferiorparietal, thalamo-inferioparietal, and thalamofrontal tracts. When focusing on patients, a stronger relationship between structural integrity of thalamo-inferiorparietal tracts and thalamic metabolism in patients who have emerged from the minimally conscious state as compared with patients with disorders of consciousness was found. The latter finding was in line with the mesocircuit hypothesis for the emergence of consciousness. The findings showed a positive function-structure relationship within most regions of the DMN. Hum Brain Mapp 37:3707-3720, 2016. © 2016 Wiley Periodicals, Inc.

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Experimental demonstration of the frequency shift of photonic bandgaps due to refractive index scaling using D2O-filled hollow-core photonic crystal fibers is presented. The results confirm a simple scaling law for bandgaps in fibers in which the low-index medium is varied.

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Pure rotational stimulated Raman scattering spectra containing nine strong spectral components were generated from a approximately 11 m long hollow-core photonic crystal fiber filled with hydrogen and pumped with nanosecond pulses having energies around 100-300 nJ. Observation of both transient and steady-state scattering threshold behavior is reported. Passage from the transient to the steady state is observed with a pulse as long as 14 ns. Convenient analytical expressions for energy and power threshold are deduced for the present configuration.

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We report on stimulated Raman scattering in an approximately 1-meter-long hollow-core photonic crystal fiber filled with hydrogen gas under pressure. Light was guided and confined in the 15-micrometer-diameter hollow core by a two-dimensional photonic bandgap. Using a pulsed laser source (pulse duration, 6 nanoseconds; wavelength, 532 nanometers), the threshold for Stokes (longer wavelength) generation was observed at pulse energies as low as 800 +/- 200 nanojoules, followed by a coherent anti-Stokes (shorter wavelength) generation threshold at 3.4 +/- 0.7 microjoules. The pump-to-Stokes conversion efficiency was 30 +/- 3% at a pulse energy of only 4.5 microjoules. These energies are almost two orders of magnitude lower than any other reported energy, moving gas-based nonlinear optics to previously inaccessible parameter regimes of high intensity and long interaction length.

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BACKGROUND: Both metoprolol and carvedilol improve cardiac function and prolong survival in patients with heart failure. Carvedilol has broader antiadrenergic effects than metoprolol, but it is not clear whether this characteristic is associated with greater benefits on cardiac function during long-term treatment. STUDY DESIGN: We performed a meta-analysis of all 19 randomized controlled trials of carvedilol or metoprolol that measured left ventricular ejection fraction before and after an average of 8.3 +/- 0.1 months of treatment in 2184 patients with chronic heart failure. The mean daily doses were 58 +/- 1 mg of carvedilol and the equivalent of 162 +/- 1 mg of extended-release metoprolol. In the 15 placebo-controlled trials, the mean ejection fraction increased more in the trials of carvedilol than in the trials of metoprolol (placebo-corrected increases of +0.065 and +0.038, respectively), P = .0002. In the 4 active-controlled trials that compared metoprolol directly with carvedilol, the mean ejection fraction also increased more in the carvedilol groups than in the metoprolol groups (+0.084 on carvedilol and +0.057 on metoprolol, respectively), P = .009. The difference in favor of carvedilol in the active-controlled trials was nearly identical to the difference observed in the placebo-controlled trials and was apparent in patients with and without coronary artery disease. CONCLUSION: Long-term treatment with carvedilol produces greater effects on left ventricular ejection fraction than metoprolol when both drugs are prescribed in doses similar to those that have been shown to prolong life.

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