101 research outputs found
How much milk of magnesia would be required to neutralise Kawah Ijenâs acid lake?
This paper investigates the amount of milk of magnesia, a common antacid, that would be required to neutralise the lake of sulfuric acid present in the crater of the Kawah Ijen volcano. The mode of neutralisation is discussed in terms of ionic interactions, and the theoretical volume of antacid was calculated using the mathematical relationship between pH and concentration. Assuming that the pH of the lake was, on average, 0.3, it was found that approximately 2.192x1012 400Â mg milk of magnesia tablets would be required to elevate the average pH to 7
Could you survive on celery alone?
This paper examines the feasibility of surviving on a diet consisting exclusively of celery. It provides an estimate of the average basal metabolic rate (BMR) of an adult female, and uses this as the basis for calculations to determine the amount of celery required to maintain a healthy calorific intake. This is compared to the average volume of food consumed by an adult, and assessed for nutritional deficiencies and overdoses. It was determined that an adult female would require a daily intake of over 10kg of celery, and although this would provide sufficient protein and carbohydrates for survival, 10.05kg is not considered to be feasible amount to consume per day. It was also found that certain micronutrients in celery would be detrimental to health if consumed in such large quantities
How many strides from Hobbiton to Mordor?
This paper uses ratios in order to determine the number of strides an average sized hobbit would have to take to complete the journey from Hobbiton to Mount Doom. It was found that an average human male is approximately 1.7 times taller than the average hobbit, making a hobbitâs stride length around 46 centimetres. This value was then applied to the distance between the start and end points of the quest, showing that the hobbit would be required to take a grand total of 4870433 strides to complete the journey
Assessment of regional gray matter loss in dementia with Lewy bodies: a surface-based MRI analysis.
OBJECTIVE: To compare magnetic resonance imaging (MRI) patterns of cortical thinning in subjects with dementia with Lewy bodies (DLB), Alzheimer's disease (AD), and normal aging and investigate the relationship between cortical thickness and clinical measures. METHODS: Study participants (31 DLB, 30 AD, and 33 healthy comparison subjects) underwent 3-Tesla T1-weighted MRI and completed clinical and cognitive assessments. We used the FreeSurfer analysis package to measure cortical thickness and investigated the patterns of cortical thinning across groups. RESULTS: Cortical thinning in AD was found predominantly in the temporal and parietal areas extending into the frontal lobes (N = 63, df = 59, t >3.3, p 3.6, p 2.8, p <0.01 uncorrected). CONCLUSION: Cortical thickness may be a sensitive measure for characterising gray matter loss in DLB and highlights important structural imaging differences between the conditions.The study was funded by the Sir Jules Thorn Charitable Trust [grant ref: 05/JTA] and supported by the National Institute for Health Research (NIHR) Newcastle Biomedical Research Centre in Ageing and Chronic Disease and Biomedical Research Unit in Lewy Body Dementia based at Newcastle upon Tyne Hospitals NHS Foundation Trust and Newcastle University, and the Biomedical Research Centre and Unit in Dementia based at Cambridge University Hospitals NHS Foundation Trust.This is the accepted manuscript. The final version is available from Elsevier at http://www.sciencedirect.com/science/article/pii/S106474811400219X
Longitudinal and quantitative MRI in AD
Quantitative MRI provides important information about tissue properties in brain both in normal ageing and in degenerative disorders. Although it is well known that those with Alzheimer's disease (AD) show a specific pattern and faster rate of atrophy than controls, the precise spatial and temporal patterns of quantitative MRI in AD are unknown. We aimed to investigate neuroimaging correlates of AD using serial quantitative MRI. In our study, twenty-one subjects with AD and thirty-two similar-aged healthy controls underwent two serial MRI scans at baseline and 12 months. Tissue characteristics were captured using two quantitative MRI parameters: longitudinal relaxation time (qT1) and transverse relaxation time (qT2). The two groups (AD and controls) were statistically compared using a voxel based quantification (VBQ) method based on Matlab and SPM8. At baseline, subjects with AD showed a significant reduction of qT1 and qT2 compared to controls in bilateral temporal and parietal lobes, hippocampus, and basal ganglia. This pattern was also observed at follow-up. Longitudinally, in AD we found a significant increase rather than further reduction of qT1 and qT2 from the baseline in bilateral hippocampus, thalamus and right caudate nucleus. In addition, the longitudinal change of qT1 in left hippocampus was negatively correlated with cognitive decline in AD over the 1-year period, and the general disease severity significantly predicted the amount of increase of qT1 in bilateral hippocampus over 12 months. The longitudinal change of qT2 in left parahippocampus correlated with change in neuropsychiatric features over time. In summary, quantitative MRI parameters were reduced in AD cross-sectionally, but increased over time, showing distinct spatiotemporal patterns from the atrophy in AD. We also showed the clinical relevance of quantitative MRI parameters, indicating their potential promise as new imaging markers in AD.The study was funded by the Sir Jules Thorn Charitable Trust (grant ref: 05/JTA) and was supported by the National Institute for Health Research (NIHR) Newcastle Biomedical Research Centre and the Biomedical Research Unit in Lewy Body Dementia based at Newcastle upon Tyne Hospitals National Health Service (NHS) Foundation Trust and Newcastle University and the NIHR Biomedical Research Centre and Biomedical Research Unit in Dementia based at Cambridge University Hospitals NHS Foundation Trust and the University of Cambridge. The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health. L. Su, A. Blamire, R. Watson, J. He and B. Aribisala report no disclosures. J. OâBrien has been a consultant for GE Healthcare, Servier, and Bayer Healthcare and has received honoraria for talks from Pfizer, GE Healthcare, Eisai, Shire, Lundbeck, Lilly, and Novartis.This is the author accepted manuscript. The final version is available from Bentham Science via http://dx.doi.org/10.2174/156720501366615111614141
Tissue microstructural changes in dementia with Lewy bodies revealed by quantitative MRI.
We aimed to characterize dementia with Lewy bodies (DLB) by the quantitative MRI parameters of longitudinal relaxation time (qT1) and transverse relaxation time (qT2). These parameters reflect potential pathological changes in tissue microstructures, which may be detectable noninvasively in brain areas without evident atrophy, so may have potential value in revealing the early neuropathological changes in DLB. We conducted a cross-sectional study of subjects with DLB (N = 35) and similarly aged control participants (N = 35). All subjects underwent a detailed clinical and neuropsychological assessment and structural and quantitative 3T MRI. Quantitative MRI maps were obtained using relaxation time mapping methods. Statistical analysis was performed on gray matter qT1 and qT2 values. We found significant alterations of quantitative parameters in DLB compared to controls. In particular, qT1 decreases in bilateral temporal lobes, right parietal lobes, basal ganglia including left putamen, left caudate nucleus and left amygdala, and left hippocampus/parahippocampus; qT2 decreases in left putamen and increases in left precuneus. These regions showed only partial overlap with areas where grey matter loss was found, making atrophy an unlikely explanation for our results. Our findings support that DLB is predominantly associated with changes in posterior regions, such as visual association areas, and subcortical structures, and that qT1 and qT2 measurement can detect subtle changes not seen on structural volumetric imaging. Hence, quantitative MRI may compliment other imaging techniques in detecting early changes in DLB and in understanding neurobiological changes associated with the disorder.This is the author accepted manuscript. The final version is available from Springer via http://dx.doi.org/10.1007/s00415-014-7541-
Treatment initiation for parkinson's disease in Australia 2013-2018 : a nation-wide study
Background Guidelines highlight the importance of an individualized approach to treatment initiation for Parkinson's disease. Our aim was to investigate initiation of anti-Parkinson medication in Australia from 2013-2018, and to determine factors predicting choice of initial treatment. Methods Cohort of new-users (N = 4,887) of anti-Parkinson medication aged >= 40 years were identified from a 10% random representative sample of national medication dispensing data from July-2013 to June-2018. Changes in treatment initiation were examined across the whole cohort and stratified by age and sex. Results Treatment initiation was most frequent with levodopa followed by non-ergot dopamine agonists (DAs) and anticholinergics. Two thirds initiated with levodopa across the study period. Initiation with non-ergot DAs increased from 22 to 27% (rate ratio, RR 1.23, 95% confidence interval, CI 1.02-1.47) and initiation with anticholinergics decreased from 6.9% to 2.4% (RR 0.34, 95% CI 0.21-0.55) from 2013-2018. Among persons aged >= 65 years, one third of women and one fourth of men initiated on levodopa. Among women aged = 65 years, consistent with current guidelines. Whilst the value of levodopa sparing strategies is unclear, treatment initiation with DA has become increasingly common relative to levodopa among women but not among men aged < 65 years.Peer reviewe
Longitudinal assessment of global and regional atrophy rates in Alzheimer's disease and dementia with Lewy bodies.
BACKGROUND & OBJECTIVE: Percent whole brain volume change (PBVC) measured from serial MRI scans is widely accepted as a sensitive marker of disease progression in Alzheimer's disease (AD). However, the utility of PBVC in the differential diagnosis of dementia remains to be established. We compared PBVC in AD and dementia with Lewy bodies (DLB), and investigated associations with clinical measures. METHODS: 72 participants (14 DLBs, 25 ADs, and 33 healthy controls (HCs)) underwent clinical assessment and 3 Tesla T1-weighted MRI at baseline and repeated at 12 months. We used FSL-SIENA to estimate PBVC for each subject. Voxelwise analyses and ANCOVA compared PBVC between DLB and AD, while correlational tests examined associations of PBVC with clinical measures. RESULTS: AD had significantly greater atrophy over 1 year (1.8%) compared to DLB (1.0%; p = 0.01) and HC (0.9%; p < 0.01) in widespread regions of the brain including periventricular areas. PBVC was not significantly different between DLB and HC (p = 0.95). There were no differences in cognitive decline between DLB and AD. In the combined dementia group (AD and DLB), younger age was associated with higher atrophy rates (r = 0.49, p < 0.01). CONCLUSIONS: AD showed a faster rate of global brain atrophy compared to DLB, which had similar rates of atrophy to HC. Among dementia subjects, younger age was associated with accelerated atrophy, reflecting more aggressive disease in younger people. PBVC could aid in differentiating between DLB and AD, however its utility as an outcome marker in DLB is limited.This work was supported by the Sir Jules Thorn Charitable Trust (grant number 05/JTA), the NIHR Biomedical Research Unit in Dementia and the Biomedical Research Centre awarded to Cambridge University Hospitals NHS Foundation Trust and the University of Cambridge, and the NIHR Biomedical Research Unit in Dementia and the Biomedical Research Centre awarded to Newcastle upon Tyne Hospitals NHS Foundation Trust and the Newcastle University. Elijah Mak was in receipt of a Gates Cambridge, PhD studentship.This is the final published version. It first appeared at http://www.sciencedirect.com/science/article/pii/S2213158215000182#
Recommended from our members
Progressive cortical thinning and subcortical atrophy in dementia with Lewy bodies and Alzheimer's disease.
Patterns of progressive cortical thinning in dementia with Lewy bodies (DLB) remain poorly understood. We examined spatiotemporal patterns of cortical thinning and subcortical atrophy over 12 months in DLB (n = 13), compared with Alzheimer's disease (AD) (n = 23) and healthy control subjects (HC) (n = 33). Rates of temporal thinning in DLB were relatively preserved compared with AD. Volumetric analyses subcortical changes revealed that the AD group demonstrated significantly increased hippocampal atrophy (-5.8%) relative to the HC (-1.7%; p < 0.001) and DLB groups (-2.5%, p = 0.006). Significant lateral ventricular expansion was also observed in AD (8.9%) compared with HC (4.3%; p < 0.001) and DLB (4.7%; p = 0.008) at trend level. There was no significant difference in subcortical atrophy and ventricular expansion between DLB and HC. In the DLB group, increased rates of cortical thinning in the frontal and parietal regions were significantly correlated with decline in global cognition (Mini-Mental State Examination) and motor deterioration (Unified Parkinson's Disease Rating Scale 3), respectively. Overall, AD and DLB are characterized by different spatiotemporal patterns of cortical thinning over time. Our findings warrant further consideration of longitudinal cortical thinning as a potential imaging marker to differentiate DLB from AD.This work was supported by the Sir Jules Thorn Charitable Trust
(Grant number 05/JTA), the NIHR Biomedical Research Unit in Dementia
and the Biomedical Research Centre awarded to Cambridge
University Hospitals NHS Foundation Trust and the University of
Cambridge, and the NIHR Biomedical Research Unit in Dementia
and the Biomedical Research Centre awarded to Newcastle upon
Tyne Hospitals NHS Foundation Trust and the Newcastle University.
Elijah Mak was in receipt of a Gates Cambridge PhD studentship.
Elijah Mak formulated the research question, performed the statistical
analyses, interpreted the results, and wrote the article. Li Su
and Guy Williams assisted with the interpretation of the results and
provided comments and additional suggestions for revisions of the
draft. Rosie Watson recruited and assessed study participants,
assisted with the interpretation of the results, and reviewed the
article. Michael Firbank designed the imaging protocol, assisted
with the interpretation of the results, and reviewed the article.
Andrew Blamire obtained funding for the project, designed the
imaging protocol, undertook routine quality assurance on the MR
system, assisted with the interpretation of the results, and reviewed
the article. John OâBrien obtained funding for the project, designed
the imaging protocol, assisted with recruitment of study participants,
assisted with the interpretation of the results, and reviewed
the article. All authors approved the final article.This is the accepted manuscript for a paper published in Neurobiology of Aging Volume 36, Issue 4, April 2015, Pages 1743â1750, DOI: 10.1016/j.neurobiolaging.2014.12.03
- âŠ