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Hörmander Type Fourier Multiplier Theorem and Nikolskii Inequality on Quantum Tori, and Applications
No full textIn this paper, we study Hörmander type Fourier multiplier theorem and the Nikolskii inequality on quantum tori. On the way to obtain these results, we also prove some classical inequalities such as the Paley, Hausdorff-Young-Paley, Hardy-Littlewood, and Logarithmic Sobolev inequalities on quantum tori. As applications we establish embedding theorems between Sobolev, Besov spaces as well as embeddings between Besov and Wiener and Beurling spaces on quantum tori. We also analyse β-versions of Wiener and Beurling spaces and their embeddings, and interpolation properties of all these spaces on quantum tori. As an application of the study, we also derive a version of the Nash inequality, and the time decay for solutions of a heat type equation
Prediction models for incident stroke in the community: a systematic review and meta-analysis of predictive performance.
Get PDFAIMS: Stroke is the second leading cause of death and the third leading cause of disability worldwide. We performed a systematic review and meta-analysis of multivariable models applicable to the prediction of incident stroke in community cohorts. METHODS AND RESULTS: Ovid Medline and Embase were searched for studies related to stroke and prediction models from inception to 3 November 2025. Measures of discrimination were extracted and pooled by Bayesian meta-analysis, with heterogeneity assessed through a 95% prediction interval (PI). Risk of bias was assessed using the Prediction model Risk Of Bias Assessment Tool and certainty in effect estimates by Grading of Recommendations, Assessment, Development and Evaluation. Forty-one studies met the inclusion criteria, describing 80 prediction models, with two (R-FSRS and Basic IS) eligible for meta-analysis, including 969 514 participants. Both R-FSRS (summary c-statistic 0.714, 95% CI 0.681-0.747) and Basic IS (0.709, 95% CI 0.647-0.769) showed acceptable discrimination performance. Risk of bias was high in 66% of models, and both models showed reduced performance when excluding development cohorts and studies at high risk of bias (R-FSRS, 0.667, 95% CI 0.604-0.727; Basic IS 0.701; 95% CI 0.583-0.807). Only 43% of studies reported calibration, and no model underwent clinical utility analysis or a clinical impact study. CONCLUSION: Many models have been derived for stroke prediction, however, they are rarely externally validated, and studies are limited by a high risk of bias, poor reporting of calibration and a lack of clinical utility analysis or prospective validation. Thus, the evidence base is insufficient to translate these models to clinical practice
Wearable ultrasound sensor
No full textAs a non-ionizing, non-invasive imaging technology, medical ultrasound has been widely used in medical monitoring and disease diagnosis. Its real-time imaging capability, deep tissue penetration and high spatial resolution make it an important tool for doctors to identify causes and make diagnostic decisions. There is no doubt that long-term continuous monitoring of the human body's physiological state is of great significance to improving clinical diagnosis and health management capabilities. Wearable medical ultrasound devices make continuous, noninvasive, and real-time monitoring possible in non-clinical environments. Wearable medical ultrasound devices rely not only on compatible flexible materials and advanced micromachining technology, but also on precise electrical engineering design. In this thesis, we demonstrate the fabrication of wearable ultrasound sensors, including single-element device and phased array device, and apply them into the application of blood pressure and blood flow measurements, gesture recognition and ultrasound imaging, respectively. The research work conducted in this thesis focuses on four topics: 1. The digital mirror device (DMD)-based photolithography was applied for fabricating the flexible circuits; 2. A single-element device using an erbium-doped PMN-PT ceramic was developed for biomedical sensing, enabling non-invasive blood pressure monitoring and flow velocity detection in vessel-mimicking phantoms; 3. A single-element device based on a 1–3 piezoelectric composite and flexible circuit achieved over 95% accuracy in recognising 24 American Sign Language gestures, demonstrating its potential in human–machine interaction; 4. The DMD-based photolithography method was extended to construct a linear electrode array on a 1–3 piezoelectric composite, which was integrated with a flexible circuit to create a wearable ultrasound phased array. This device demonstrated high-quality two-dimensional Bmode and C-mode imaging, validating its potential for continuous soft tissue and organ imaging
A novel human disorder: QSOX2 deficiency-induced growth restriction, gastrointestinal dysmotility and immune dysfunction highlights a new mechanism of disease
No full textDysregulated pathways reveal NOVEL mechanistic insights underlying HMGA2-related growth failure in Silver Russell Syndrome
No full textEpstein-Barr Virus and Memory B-cells in Patients with Multiple Sclerosis
No full textEpstein-Barr Virus (EBV) is a human oncogenic lymphotropic virus that belongs to the Herpesviridae family of viruses. It is ubiquitous among the adult population- establishing latent infections in more than 90% of the world’s population. Primary infections by EBV are typically asymptomatic in children but can cause infectious mononucleosis in the adult population. The virus is also associated with a wide range of malignancies such as Burkitt’s lymphoma in susceptible individuals. Multiple sclerosis (MS) is an autoimmune chronic inflammatory demyelinating disease of the central nervous system (CNS), typically affecting young adults and leading to irreversible physical and mental disabilities. In a recent large cohort study of young adults in the U.S. military, infection with EBV was shown to increase the risk of MS by 32-fold and epidemiological data support EBV as being necessary, but not sufficient, for the development of MS. EBV has long been implicated in the pathogenesis of MS, but whether it acts as an early “hit-and-run” trigger or as an ongoing driver of disease remains unresolved. This thesis investigated EBV activity in MS through complementary analyses of viral loads, viral genomics, and B-cell receptor (BCR) repertoires in saliva, peripheral blood mononuclear cells (PBMCs), and EBV-transformed spontaneous lymphoblastoid cell lines (S-LCLs). Quantification of EBV DNA by qPCR and dPCR revealed no significant elevation of viral loads in saliva or blood subsets from MS compared with non-MS participants, though subtle sex-related differences and altered compartmentalisation of EBV within B-cell subsets were observed. S-LCLs established from both groups faithfully reproduced EBV transformation biology, displaying canonical B-cell phenotypes and robust cytokine responses. Transformation efficiency was lower in MS samples, suggesting intrinsic disease-related differences in B-cell susceptibility. Pharmacological studies showed that sodium butyrate induced lytic gene expression but suppressed proliferation and viral release, while antivirals (Acyclovir, Penciclovir) effectively blocked EBV replication, validating S-LCLs as tractable models for therapeutic exploration. Genomic analyses highlighted viral load as a key determinant of sequencing outcomes, with S-LCLs yielding high-quality genomes and saliva showing greater heterogeneity, particularly in MS participants. No MS-specific strain or mutational burden was identified, but increased salivary diversity suggested altered viral persistence or immune control. BCR repertoire analyses further demonstrated that EBV-driven outgrowths recapitulate the ecology of human B cells, encompassing naïve, memory, and atypical subsets. Most S-LCL clones were single-isotype, with rare multi-isotype lineages reflecting sequential class switching. Somatic hypermutation patterns spanned naïve-like to affinity-matured memory states, and modestly greater PBMC–S-LCL overlap was observed in MS donors, consistent with the central role of memory B cells in disease. PBMC repertoires themselves were broadly similar between MS and non-MS, with only subtle enrichments in IGHV1-69 and IGHV3-30. Together, my findings suggest that EBV’s contribution to MS is not mediated by the wholistic increases in viral burden or strain-specific mutations, but by more subtle and sustained influences on B-cell biology, particularly within the memory compartment. This supports the view of EBV as a continuing driver of immune dysregulation in MS. Future work should prioritise longitudinal, multi-compartment, and single-cell studies, alongside therapeutic strategies targeting EBV activity
A novel Mediterranean diet-inspired supplement reduces hippocampal amyloid deposits and microglial activation through the modulation of the microbiota gut-brain axis in 5xFAD mice
Get PDFIn vitro characterization of strontium containing bioactive glasses with hydroxyapatite mixtures for the occlusion of the dentinal tubules
Get PDFIntroduction Dentine Hypersensitivity (DH) is a common and prevalent condition that is caused by the exposure of dentinal tubules and results in a rapid and sharp pain when encounters a stimulus. BAGs have been observed as an effective treatment option to prevent DH by occluding dentinal tubules. Incorporating Sr+2 with calcium in BAGs has been observed to be effective due to the faster dissolution of the glass network and the anti-cariogenic role of Sr2+. Therefore, different percentages of BAGSr and HA mixtures were tested through various techniques to observe the efficacy of the combination of BAGSr and HA mixtures to observe in vitro apatite formation and tubular occlusion on the dentine discs. Objectives: To assess the effectiveness of different percentages of BAGSr and HA mixtures to observe in vitro apatite formation and tubular occlusion on the dentine discs. Results: Particle size analysis has revealed a coarser nature of BAGSr as compared to synthetic HA. The degradation of BAGSr was observed to be faster than the conventional BAGs due to the larger ionic radius of the Sr2+. pH measurements have indicated a significant rise, that is an indication for the degradation of the glass and apatite formation followed by ATR-FTIR, powder XRD, ICP/OES analysis. ISE study has revealed a significant release of fluoride with the increase of the BAGSr percentage in the formulations whereas 19F and 31P ss-MAS NMR have confirmed the formation of the mixed Ca/Sr FAp with BAGSr and HA. The HC study revealed 80% BAGSr and 20% HA mixture have shown a higher reduction in the fluid flow rates of the dentine discs. However, SEM analysis has indicated some surface occlusion with the BAGSr and HA mixtures. Conclusion: The investigations of the current in vitro study have concluded that the BAGSr and HA mixtures can buffer the pH in acidic conditions, release favorable ions for the apatite formation and aids remineralization. The presence of Sr2+ has shown beneficial effects on the structure of glass. In addition, the presence of fluoride resulted in the formation Sr/Ca FAp layer that can cover the dentine surface or occlude the dentinal tubules to some extent. Therefore, these formulations could be an effective preventive option for DH with further modifications. However, further assessment and in vivo studies are required to observe the effectiveness of these materials for tubular occlusion
