Sapphire optical fibre interferometric sensors

This thesis is mainly concerned with the development of single crystal fibre interferometric sensors. By studying the functional relationship between the angle of wedge-shaped air gap and the separation of consecutive fringes of equal thickness, results shows that the percentage difference of angles between the method of interference fringes and the direct calculated method is about 3.99%. Thus, a procedure of prototype was established to monitor the process of fabrication of a Fabry-Perot cavity. An intrinsic sapphire fibre-optic Fabry-Perot sensor was fabricated, and the functional relationship between the output of interference signal of the intrinsic sapphire fibre-optic Fabry-Perot sensor and temperature was deduced. The fitting equation, the functional relationship between temperature and the output of the number of interference fringes of the intrinsic sapphire fibre-optic Fabry-Perot sensor, was obtained by data fitting. There is a near linear relationship between the temperature measured and the output signal of the intrinsic sapphire fibre- optic Fabry-Perot sensor for the range of temperature 75 °C - 435 °C. An extrinsic sapphire fibre-optic Fabry-Perot sensor was fabricated, and the functional relationship between the output of interference signal of the extrinsic sapphire fibre-optic Fabry-Perot sensor and temperature was deduced. High temperature ceramic adhesive based on aluminum oxide was presented to solve the problem of unmatched thermal expansion between the support materials and the extrinsic sapphire fibre-optic Fabry-Perot sensor. Theoretical analysis showed that during the process of the fabrication of the interferometer cavity, the length of Fabry-Perot cavity for fabricating should be tightly controlled. Phase relationships between the output of the interference signal of a monolithic sapphire fibre-optic Fabry-Perot sensor and the angular frequency of sound wave was deduced. Some monolithic sapphire Fabry-Perot cavities were fabricated, and their internal surfaces were observed. The optical quality of the internal surface of the melted end of the sapphire Fabry-Perot cavities was assessed by Michelson interferometric testing. The experiments showed that interference fringes of equal inclination could be achieved if the internal surface of the monolithic sapphire Fabry-Perot cavities were approximately planar surface. Obviously, there is the potential to fabricate a monolithic sapphire fibre-optic Fabry-Perot sensor by the sapphire tube sheath method. Four problems are presented to discuss which should be solved in future in consideration to the structure and assembly of the monolithic sapphire fibre-optic Fabry-Perot sensor: This study in this thesis has elucidated the problems associated with procedures in fabrication, assembly, and test of sapphire fibre-optic Fabry-Perot sensor, and achieved greater insights into fabrication of the monolithic sapphire fibre-optic Fabry-Perot sensor which shows the market potential of such an approach in Aerospace and Automobile applications

VitTCR: A deep learning method for peptide recognition prediction

Summary: This study introduces VitTCR, a predictive model based on the vision transformer (ViT) architecture, aimed at identifying interactions between T cell receptors (TCRs) and peptides, crucial for developing cancer immunotherapies and vaccines. VitTCR converts TCR-peptide interactions into numerical AtchleyMaps using Atchley factors for prediction, achieving AUROC (0.6485) and AUPR (0.6295) values. Benchmark analysis indicates VitTCR’s performance is comparable to other models, with further comparative studies suggested to understand its effectiveness in varied contexts. Additionally, integrating a positional bias weight matrix (PBWM), derived from amino acid contact probabilities in structurally resolved pMHC-TCR complexes, slightly improves VitTCR’s accuracy. The model’s predictions show weak yet statistically significant correlations with immunological factors like T cell clonal expansion and activation percentages, underscoring the biological relevance of VitTCR’s predictive capabilities. VitTCR emerges as a valuable computational tool for predicting TCR-peptide interactions, offering insights for immunotherapy and vaccine development

Deposition of thin films on basalt fibers surface by atmospheric pressure plasma with different siloxane precursors

In this study, surface modification of basalt fibers (BFs) utilizing atmospheric pressure plasma deposition was carried out. Using this one-step deposition approach, three siloxane precursors with different structures including methyltrimethoxysilane (MTMS), hexamethyldisiloxane (HMDSO), and tetramethoxysilane (TMOS) were deposited on BFs surface, respectively. The physicochemical properties of the thin films from three different siloxane compounds are elucidated. In comparison with MTMS-coated sample, HMDSO-coated and TMOS-coated BFs surfaces feature an improved thermal insulation performance. The results demonstrate that atmospheric pressure plasma deposition is an efficient approach to modify flexible materials surface with improved thermal insulation. Moreover, it provides a reference to decide which precursor type is preferred for certain applications

Social Incentives Anticipation and Consummation: Investigating Neural Activity in Women Using Methamphetamine

Individuals with methamphetamine use disorder are considered to have enhanced reactivity to rewards or drug cues. However, whether this holds true in the social incentives processing is still unclear. The current study investigated the electroencephalographical (EEG) evidence of social incentives processing in women with methamphetamine use disorder (MA group, n = 19) and in a healthy control group (HC group, n = 20) using social incentive delay (SID) tasks. In the SID, participants received a "Like" (e.g., thumbs up) or "Unlike" (e.g., thumbs down) from WeChat emojis as social incentives, or neutral feedback. During the anticipation stage, the Cue-P3 and stimulus-preceding negativity (SPN) were larger for the social incentives condition than for the neutral condition. During the consummation stage, the feedback-related negativity (FRN) was marginally significantly larger in the HC group than the MA group for the social incentive condition, whereas there was no significant difference between the groups for neutral condition. Interestingly, the FB-P3 was larger for social positive feedback than for social negative feedback in the MA group, but not in HC group. Furthermore, only the HC group showed significant positive correlation between the anticipatory event-related brain potential (ERP, such as Cue-P3) and the consummatory ERP (FB-P3) in the social incentive condition. The findings suggest that women with MA use disorder have a blunted neural response to the processing of social incentives and a blunted neural response to negative social feedback, which helps to elucidate the neural mechanisms of social incentives processing in individuals with MA use disorder

Maintenance regimen of GM‐CSF with rituximab and lenalidomide improves survival in high‐risk B‐cell lymphoma by modulating natural killer cells

Abstract Background The treatment of high‐risk B‐cell lymphoma (BCL) remains a challenge, especially in the elderly. Methods A total of 83 patients (median age 65 years), who have achieved a complete response after induction therapy, were divided into two groups: R2 + GM‐CSF regimen (lenalidomide, rituximab, granulocyte‐macrophage colony‐stimulating factor [GM‐CSF]) as maintenance therapy (n = 39) and observation (n = 44). The efficacy of the R2 + GM‐CSF regimen as maintenance in patient with high‐risk BCL was analyzed and compared with observation. Results The number of natural killer cells in patients increased after R2 + GM‐CSF regimen administration (0.131 × 109/L vs. 0.061 × 109/L, p = 0.0244). Patients receiving the R2 + GM‐CSF regimen as maintenance therapy had longer remission (duration of response: 18.9 vs. 11.3 months, p = 0.001), and longer progression‐free survival (not reached (NR) vs. 31.7 months, p = 0.037), and overall survival (OS) (NR vs. NR, p = 0.015). The R2 + GM‐CSF regimen was safe and well tolerated. High international prognostic index score (p = 0.012), and high tumor burden (p = 0.005) appeared to be independent prognostic factors for worse PFS. Conclusions The maintenance therapy of R2 + GM‐CSF regimen may improve survival in high‐risk BCL patients, which might be modulated by amplification of natural killer cells. The efficacy of the R2 + GM‐CSF maintenance regimen has to be further validated in prospective random clinical trials

Discovery of 4,7-Diamino-5-(4-phenoxyphenyl)-6-methylene-pyrimido[5,4‑<i>b</i>]pyrrolizines as Novel Bruton’s Tyrosine Kinase Inhibitors

An alternative medicinal chemistry approach was conducted on Bruton’s tyrosine kinase (BTK) inhibitor <b>1</b> (ibrutinib) by merging the pyrazolo­[3,4-<i>d</i>]­pyrimidine component into a tricyclic skeleton. Two types of compounds were prepared, and their biochemical activities on BTK as well as stereochemistry effects were determined. Structural optimization focusing on the reactive binding group to BTK Cys481 and on the metabolic site guided by metabolic study were conducted. <b>7S</b> was identified as the most potent showing an IC₅₀ value of 0.4 nM against BTK and 16 nM against BTK-dependent TMD8 cells. Compared to <b>1</b>, <b>7S</b> was slightly more selective with strong inhibition on the B-cell receptor signaling pathway. In a TMD8 cell-derived animal xenograft model, <b>7S</b> showed a relative tumor volume of 5.3 at 15 mg/kg QD dosage that was more efficacious than <b>1</b> (RTV 6.6) at a higher dose of 25 mg/kg QD. All these results suggest <b>7S</b> as a new BTK inhibitor worthy of further profiling

Discovery of 4,7-Diamino-5-(4-phenoxyphenyl)-6-methylene-pyrimido[5,4‑<i>b</i>]pyrrolizines as Novel Bruton’s Tyrosine Kinase Inhibitors

An alternative medicinal chemistry approach was conducted on Bruton’s tyrosine kinase (BTK) inhibitor <b>1</b> (ibrutinib) by merging the pyrazolo­[3,4-<i>d</i>]­pyrimidine component into a tricyclic skeleton. Two types of compounds were prepared, and their biochemical activities on BTK as well as stereochemistry effects were determined. Structural optimization focusing on the reactive binding group to BTK Cys481 and on the metabolic site guided by metabolic study were conducted. <b>7S</b> was identified as the most potent showing an IC₅₀ value of 0.4 nM against BTK and 16 nM against BTK-dependent TMD8 cells. Compared to <b>1</b>, <b>7S</b> was slightly more selective with strong inhibition on the B-cell receptor signaling pathway. In a TMD8 cell-derived animal xenograft model, <b>7S</b> showed a relative tumor volume of 5.3 at 15 mg/kg QD dosage that was more efficacious than <b>1</b> (RTV 6.6) at a higher dose of 25 mg/kg QD. All these results suggest <b>7S</b> as a new BTK inhibitor worthy of further profiling