110 research outputs found
Functional brain imaging with fMRI and MEG
The work described in this thesis was performed by the author, except where indicated. All the studies were accomplished on the 3 Tesla system within the Magnetic Resonance Centre at the University of Nottingham, and the Wellcome Trust MEG Laboratory at the Aston University during the period between October 1999 and June 2005. Functional Magnetic Resonance Imaging (fMRI) and Magnetoencephalography (MEG) are two promising brain function research modalities, sensitive to the hemodynamic and electrophysiological responses respectively during brain activites. The feasibility of joint employment of both modalities was examined in both spatial and temporal domains. A somatosensory tactile stimulus was adopted to induce simple functional reaction. It was shown that a reasonable spatial correspondence between fMRI and MEG can be established. Attempts were made on MEG recordings to extract suitable aspects for temporal features matching fMRI with a method reflecting the physical principles. It was shown that the this method is capable of exposing the nature of neural electric activities, although further development is required to perfect the strategy
Dietary nitrate reduces skeletal muscle oxygenation response to physical exercise : a quantitative muscle functional MRI study
© 2014 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.Peer reviewedPublisher PD
Functional brain imaging with fMRI and MEG
The work described in this thesis was performed by the author, except where indicated. All the studies were accomplished on the 3 Tesla system within the Magnetic Resonance Centre at the University of Nottingham, and the Wellcome Trust MEG Laboratory at the Aston University during the period between October 1999 and June 2005. Functional Magnetic Resonance Imaging (fMRI) and Magnetoencephalography (MEG) are two promising brain function research modalities, sensitive to the hemodynamic and electrophysiological responses respectively during brain activites. The feasibility of joint employment of both modalities was examined in both spatial and temporal domains. A somatosensory tactile stimulus was adopted to induce simple functional reaction. It was shown that a reasonable spatial correspondence between fMRI and MEG can be established. Attempts were made on MEG recordings to extract suitable aspects for temporal features matching fMRI with a method reflecting the physical principles. It was shown that the this method is capable of exposing the nature of neural electric activities, although further development is required to perfect the strategy
Grey and white matter differences in Chronic Fatigue Syndrome : A voxel-based morphometry study
Conflicts of interest and source of funding The authors declare no conflicts of interest. This research was funded by the Medical Research Council (MR/J002712/1). AF is supported by Research Capability Funding from the Newcastle upon Tyne Hospitals NHS Foundation Trust and the Northumberland, Tyne and Wear NHS Foundation Trust.Peer reviewedPublisher PD
Disease activity and cognition in rheumatoid arthritis : an open label pilot study
Acknowledgements This work was supported in part by NIHR Newcastle Biomedical Research Centre. Funding for this study was provided by Abbott Laboratories. Abbott Laboratories were not involved in study design; in the collection, analysis and interpretation of data; or in the writing of the report.Peer reviewedPublisher PD
Cerebral vascular control is associated with skeletal muscle pH in chronic fatigue syndrome patients both at rest and during dynamic stimulation
Peer reviewedPublisher PD
Effects of Community Exercise Therapy on Metabolic, Brain, Physical, and Cognitive Function Following Stroke : A Randomized Controlled Pilot Trial
© The Author(s) 2014.Peer reviewedPostprintPostprin
FairBench: A Four-Stage Automatic Framework for Detecting Stereotypes and Biases in Large Language Models
Detecting stereotypes and biases in Large Language Models (LLMs) can enhance
fairness and reduce adverse impacts on individuals or groups when these LLMs
are applied. However, the majority of existing methods focus on measuring the
model's preference towards sentences containing biases and stereotypes within
datasets, which lacks interpretability and cannot detect implicit biases and
stereotypes in the real world. To address this gap, this paper introduces a
four-stage framework to directly evaluate stereotypes and biases in the
generated content of LLMs, including direct inquiry testing, serial or adapted
story testing, implicit association testing, and unknown situation testing.
Additionally, the paper proposes multi-dimensional evaluation metrics and
explainable zero-shot prompts for automated evaluation. Using the education
sector as a case study, we constructed the Edu-FairBench based on the
four-stage framework, which encompasses 12,632 open-ended questions covering
nine sensitive factors and 26 educational scenarios. Experimental results
reveal varying degrees of stereotypes and biases in five LLMs evaluated on
Edu-FairBench. Moreover, the results of our proposed automated evaluation
method have shown a high correlation with human annotations
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-
q-Space Imaging Yields a Higher Effect Gradient to Assess Cellularity than Conventional Diffusion-weighted Imaging Methods at 3.0 T : A Pilot Study with Freshly Excised Whole-Breast Tumors
N.S. supported by Biotechnology and Biological Sciences Research Council (1654748, BB/M010996/1). Study supported by the National Health Service Grampian Endowment Fund (15/1/052).Peer reviewedPublisher PD
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