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Cr3+ activated near‐infrared (NIR) phosphors are getting unprecedented attention to fabricate the broad band NIR light emitting diodes (NIR‐LEDs) for nondestructive detection, bio‐imaging, and night vision. However, it remains a major challenge to obtain ultrabroadband NIR emitting phosphor with excellent quantum yield (QY). Here, a broadband NIR emitting phosphor Mg7Ga2GeO12:Cr3+ (MGGO: Cr3+) ranging from 600 to 1300 nm with an outstanding QY (93%) and large full width of half maximum (FWHM = 226 nm) is developed, in which the site occupancy tendency of Cr3+ in MGGO host is discussed in detail through combining the structure optimization and the first‐principles theory calculation with luminescent properties at low temperature. After that, the emission intensity of MGGO:Cr3+ is improved through partial substitution of Mg2+ by alkaline‐earth ions Ca2+, Sr2+, or Ba2+, and the luminescence enhancement mechanism is also investigated. Furthermore, the NIR pc‐LED device is fabricated by combining 450 nm blue LED chip with the brightest phosphor MGGO:Cr3+/Ba2+, and its potential applications are evaluated in the field of nondestructive detection, night vision, and bio‐imaging. [ABSTRACT FROM AUTHOR]

Background: Previous studies have indicated that neurite orientation dispersion and density imaging (NODDI) could be used as a biomarker for detecting microstructural changes of brain.Purpose: To quantitatively evaluate the changes in basal ganglia (BG) and thalamus in Wilson's disease (WD) by NODDI and assess the correlation between parameters and disease severity.Study Type: Prospective case-control study.Population: In total, 24 WD patients and 25 age- and sex-matched normal controls were involved in this study.Field Strength/sequence: EPI diffusion-weighted MR images (b-values = 0, 1000, and 2000 with 30 diffusion gradient directions) were acquired on a 3T scanner.Assessment: Diffusion data were analyzed using voxel-based analysis. NODDI indices including intracellular volume fraction (Vic), orientation dispersion index (ODI), and isotropic volume fraction (Viso) were estimated from the BG and thalamus. The disease severity was assessed by two experienced neurologists based on the Global Assessment Scale (GAS). The relative importance of NODDI indices in diagnosing WD and predictive accuracy were also analyzed.Statistical Testing: The Shapiro-Wilk test, Student's t-test, χ2 test, Mann-Whitney-Wilcoxon test, Spearman rank correlation coefficient analysis and random-forest analysis were used for statistical analyses.Results: The Vic and ODI in the BG and thalamus were significantly lower in WD patients than normal controls, while the Viso in the BG and thalamus were significantly higher (P < 0.01). The Vic in the putamen and ODI in the globus pallidus were negatively correlated with clinical severity (rvic = -0.727, P < 0.001; rodi = -0.705, P < 0.001). The Vic in the putamen was the most valuable predictor for diagnosing WD and the prediction accuracy of NODDI was 95.92%.Data Conclusion: NODDI can effectively evaluate the changes of microstructure and metabolism during copper deposition in WD, and thus, it is likely to be useful in detecting the changes in the brain of this disease and assessing its progression.Level Of Evidence: 2 Technical Efficacy Stage 2 J. MAGN. RESON. IMAGING 2018;48:423-430. [ABSTRACT FROM AUTHOR]

Aims To detect specific oculomotor deficits in preclinical stage of spinocerebellar ataxia type 3 ( SCA3) and evaluate whether these abnormalities prove useful as potential biomarkers of disease progression. Methods A Chinese cohort of 56 patients with SCA3, including 12 preclinical carriers of SCA3 (pre- SCA3) and 44 manifest SCA3, and 26 healthy control individuals were recruited. We performed a detailed investigation on central oculomotor performance including fixation, gaze, smooth pursuit, prosaccade, and antisaccade using video-oculography. Results Common oculomotor features of pre- SCA3 included square-wave jerk during central fixation and gaze holding, impaired vertical smooth pursuit, slow upward saccade, and increased antisaccade error rate. In our SCA3 cohort, all oculomotor parameters were correlated with the score of the Scale for the Assessment and Rating of Ataxia, whilst some of them were correlated with disease duration. Conclusion This study showed that a series of neuropathological changes reflected by oculomotor abnormalities appeared preferentially in preclinical stage of SCA3. Accordingly, objective oculomotor preclinical signs may be useful to detect the optimum time-point for therapeutic interventions in future clinical trials of SCA3. Larger and longitudinal data are warranted to confirm our results. [ABSTRACT FROM AUTHOR]