Mapping radiation dose distribution on the Fractional Anisotropy Map: application in the assessment of treatment-induced white matter injury

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Discrepant FA reduction between the frontal and parietal lobes of post irradiation medulloblastoma survivors: preliminary findings of regional susceptibility?

In this study of 16 medulloblastoma survivors and corresponding age-matched control subjects, we tested the hypothesis that fractional anisotropy (FA) in the frontal lobe is more severely reduced than the parietal lobe after whole brain irradiation. Quantitative measurement of regional mean FA was performed using automatically generated masks. We found significant FA reduction in the frontal lobe, but not parietal lobe, in the medulloblastoma survivors compared to controls. Although more severe FA reduction in the frontal lobe was found, this difference did not achieve statistical significance. However, a trend of regional susceptibility of the frontal lobe to radiation was suggested.published_or_final_versio

Diffusion tensor MR imaging in the evaluation of Wallerian degeneration in pediatric strokes: work-in-progress

Poster Session - Pediatric Brain MR Imaging: no. 2090We use DTI to detect and quantify Wallerian degeneration (WD) in pediatric MCA strokes. Fractional anisotropy (FA) and mean diffusivity (MD)of the infarction, ipsilateral internal capsule (PLIC) and cerebral peduncle (CP) were measured in nine children and compared to the matched contralateral side. WD was characterized by statistically significant differences in FA, but not MD, of the ipsilateral PLIC and CP compared to normal side. FA was reduced in all children, whilst corresponding hyperintense signals on T2W were seen in five children. DTI is more sensitive than conventional MRI and can be used to detect and quantify WD.published_or_final_versio

Factors associated with loss of white matter anisotropy in post-treatment medulloblastoma survivors

We evaluate effects of age at cranial irradiation, time interval since irradiation and irradiation dose on white matter anisotropy in childhood medulloblastoma survivors by computing white matter fractional anisotropy (WM FA) using SPM post-processing functions. Mean percentage change in WM FA of patients compared to controls was -4.4% (sd=7.6%). Using Spearmanís correlation, there were significant associations between percentage reduction of WM FA and age at cranial irradiation (r=0.673, p=0.002) and irradiation dose (r=-0.723, p=<0.001), but not with time interval since irradiation. Multivariate regression analysis confirmed that both factors correlated significantly with percentage reduction of WM FA (adjusted r2=0.516, p=0.001).published_or_final_versio

Epilogue: the new frontiers of behavioral research on the interrelationships between ICT, activities, time use and mobility

© 2018, Springer Science+Business Media, LLC, part of Springer Nature. This special issue is a product of the international symposium on “ICT, Activities, Time Use and Travel” that was hosted by Nanjing University from 16 to 18 July 2016. The symposium brought together leading scholars from all over the world to congregate with Chinese scholars and students and to share and discuss the research frontiers at this nexus. It was motivated by a recognition of the changing goals and scope of Information and Communications Technology (ICT) research in conjunction with the development of new ICTs and the emergence of new ICT-enabled behaviors. Consequently, the symposium and later this special issue have drawn together significant scholarly contributions that provide new behavioral insights as well as new theoretical and methodological advances. The symposium culminated in three roundtable panel discussions addressing the following cross-cutting themes: (1) time use while travelling (led by Glenn Lyons); (2) ICT and travel behavior (led by Pat Mokhtarian); and (3) Big Data, activities and urban space (led by Eran Ben-Elia). In this epilogue to the special issue we offer a distillation of these discussions

Estimation of traffic matrices for LRD traffic

The estimation of traffic matrices in a communications network on the basis of a set of traffic measurements on the network links is a well known problem, for which a number of solutions have been proposed when the traffic does not show dependence over time, as in the case of the Poisson process. However, extensive measurements campaigns conducted on IP networks have shown that the traffic exhibits long range dependence. Here two methods are proposed for the estimation of traffic matrices in the case of long range dependence, their asymptotic properties are studied, and their relative merits are compared

Effects of sand burial and overstory tree age on seedling establishment in coastal Pinus thunbergii forests in the northern Shandong Peninsula, China

Coastal Pinus thunbergii (Japanese black pine) forests in the northern Shandong Peninsula of China recently experienced widespread natural regeneration failure. This study identifies critical factors that affect natural regeneration of P. thunbergii. Seeds from trees of various ages (13-32 years) were used to investigate the effects of age and burial depth in sand on germination and seedling establishment. Results show that seed density in 2-5 cm soil decreased with increased distance from the shoreline. Sand burial decreased seed germination but did not affect the relative growth rate of seedlings at depths from 0.5 to 3 cm. Germination, leaf mass ratio, and relative growth rates were higher with seedlings originating from older trees, all of which enhanced seedling resistance to sand burial. Tree age and seed burial were found to be determining factors for natural regeneration of the coastal P. thunbergii forest. Silvicultural treatments that promote quality of seed sources and mitigation of sand burial can be used in the future to improve the regeneration of these coastal forests

Role of liraglutide in Alzheimer's disease pathology

Background The described relationship between Alzheimer's disease (AD) and type 2 diabetes (T2D) and the fact that AD has no succesful treatment has led to the study of antidiabetic drugs that may limit or slow down AD pathology. Main body Although T2D treatment has evident limitations, options are increasing including glucagon-like peptide 1 analogs. Among these, liraglutide (LRGT) is commonly used by T2D patients to improve beta cell function and suppress glucagon to restore normoglycaemia. Interestingly, LRGT also counterbalances altered brain metabolism and has anti-inflammatory properties. Previous studies have reported its capacity to reduce AD pathology, including amyloid production and deposition, tau hyperphosphorylation, or neuronal and synaptic loss in animal models of AD, accompanied by cognitive improvement. Given the beneficial effects of LRGT at central level, studies in patients have been carried out, showing modest beneficial effects. At present, the ELAD trial (Evaluating Liraglutide in Alzheimer's Disease NCT01843075) is an ongoing phase IIb study in patients with mild AD. In this minireview, we resume the outcomes of LRGT treatment in preclinical models of AD as well as the available results in patients up to date. Conclusion The effects of LRGT on animal models show significant benefits in AD pathology and cognitive impairment. While studies in patients are limited, ongoing clinical trials will probably provide more definitive conclusions on the role of LRGT in AD patients

The Shapes of Cooperatively Rearranging Regions in Glass Forming Liquids

The shapes of cooperatively rearranging regions in glassy liquids change from being compact at low temperatures to fractal or ``stringy'' as the dynamical crossover temperature from activated to collisional transport is approached from below. We present a quantitative microscopic treatment of this change of morphology within the framework of the random first order transition theory of glasses. We predict a correlation of the ratio of the dynamical crossover temperature to the laboratory glass transition temperature, and the heat capacity discontinuity at the glass transition, Delta C_p. The predicted correlation agrees with experimental results for the 21 materials compiled by Novikov and Sokolov.Comment: 9 pages, 6 figure