SYNTHESIS, CHARACTERIZATION AND APPLICATIONS OF NANOSTRUCTURED MATERIALS AS NOVEL CATALYST SUPPORTS IN ETHANOL REFORMING FOR HYDROGEN PRODUCTION

Ph.DDOCTOR OF PHILOSOPH

Trace residue analysis of dicyandiamide, cyromazine, and melamine in animal tissue foods by ultra-performance liquid chromatography

AbstractAn effective sample preparation procedure using an accelerated solvent extraction (ASE) procedure, followed by cleaning with melamine molecularly imprinted polymers solid-phase extraction (MISPE) was developed. A novel and highly sensitive ASE–MISPE–ultra-performance liquid chromatography (UPLC) method was developed for effective separation and simultaneous determination of dicyandiamide (DCD), cyromazine (CYR), and melamine (MEL) in complex animal tissue foods. Under optimized conditions, good linearity was achieved with a correlation coefficient (r) of 0.9999 in the range of at least two orders of magnitude. The limit of quantification of the method was 1.7 μg/kg, 5.0 μg/kg, and 3.2 μg/kg for DCD, MEL, and CYR, which was three orders of magnitude smaller than the maximum residue limits (MRLs). The intra- and inter-day precisions (in terms of the relative standard deviation, RSD) of the three analytes were in the range of 1.7–3.1% and 3.1–6.3%, respectively. The average recoveries of analytes from blank chicken, beef, mutton, pork, and pig liver samples spiked with the three levels varied from 91.2% to 107% with RSD of 1.7–8.3% for DCD, 89.0–104% with RSD of 2.1–6.1% for CYR, and 94.8–105% with RSD of 1.1–6.6% for MEL. The proposed method has the characteristics of speed, sensitivity, and accuracy, and can be used for the routine determination of DCD, CYR, and MEL at the μg/kg level in complex animal tissue foods

Entire genome sequence analysis of genotype IX Newcastle disease viruses reveals their early-genotype phylogenetic position and recent-genotype genome size

<p>Abstract</p> <p>Background</p> <p>Six nucleotide (nt) insertion in the 5'-noncoding region (NCR) of the nucleoprotein (NP) gene of Newcaslte disease virus (NDV) is considered to be a genetic marker for recent genotypes of NDV, which emerged after 1960. However, F48-like NDVs from China, identified a 6-nt insert in the NP gene, have been previously classified into genotype III or genotype IX.</p> <p>Results</p> <p>In order to clarify their phylogenetic position and explore the origin of NDVs with the 6-nt insert and its significance in NDV evolution, we determined the entire genome sequences of five F48-like viruses isolated in China between 1946 and 2002 by RT-PCR amplification of overlapping fragments of full-length genome and rapid amplification of cDNA ends. All the five NDV isolates shared the same genome size of 15,192-nt with the recent genotype V-VIII viruses whereas they had the highest homology with early genotype III and IV isolates.</p> <p>Conclusions</p> <p>The unique characteristic of the genome size and phylogenetic position of F48-like viruses warrants placing them in a separate geno-group, genotype IX. Results in this study also suggest that genotype IX viruses most likely originate from a genotype III virus by insertion of a 6-nt motif in the 5'-NCR of the NP gene which had occurred as early as in 1940 s, and might be the common origin of genotype V-VIII viruses.</p

Intelligent Omni Surfaces assisted Integrated Multi Target Sensing and Multi User MIMO Communications

Drawing inspiration from the advantages of intelligent reflecting surfaces (IRS) in wireless networks,this paper presents a novel design for intelligent omni surface (IOS) enabled integrated sensing and communications (ISAC). By harnessing the power of multi antennas and a multitude of elements, the dual-function base station (BS) and IOS collaborate to realize joint active and passive beamforming, enabling seamless 360-degree ISAC coverage. The objective is to maximize the minimum signal-tointerference-plus-noise ratio (SINR) of multi-target sensing, while ensuring the multi-user multi-stream communications. To achieve this, a comprehensive optimization approach is employed, encompassing the design of radar receive vector, transmit beamforming matrix, and IOS transmissive and reflective coefficients. Due to the non-convex nature of the formulated problem, an auxiliary variable is introduced to transform it into a more tractable form. Consequently, the problem is decomposed into three subproblems based on the block coordinate descent algorithm. Semidefinite relaxation and successive convex approximation methods are leveraged to convert the sub-problem into a convex problem, while the iterative rank minimization algorithm and penalty function method ensure the equivalence. Furthermore,the scenario is extended to mode switching and time switching protocols. Simulation results validate the convergence and superior performance of the proposed algorithm compared to other benchmark algorithms.Comment: 30 pages, 7 figure

On the Performance of RIS-Aided Spatial Scattering Modulation for mmWave Transmission

In this paper, we investigate a state-of-the-art reconfigurable intelligent surface (RIS)-assisted spatial scattering modulation (SSM) scheme for millimeter-wave (mmWave) systems, where a more practical scenario that the RIS is near the transmitter while the receiver is far from RIS is considered. To this end, the line-of-sight (LoS) and non-LoS links are utilized in the transmitter-RIS and RIS-receiver channels, respectively. By employing the maximum likelihood detector at the receiver, the conditional pairwise error probability (CPEP) expression for the RIS-SSM scheme is derived under the two scenarios that the received beam demodulation is correct or not. Furthermore, the union upper bound of average bit error probability (ABEP) is obtained based on the CPEP expression. Finally, the derivation results are exhaustively validated by the Monte Carlo simulations.Comment: arXiv admin note: substantial text overlap with arXiv:2307.1466

Reconfigurable Intelligent Surface Aided Space Shift Keying With Imperfect CSI

In this paper, we investigate the performance of reconfigurable intelligent surface (RIS)-aided spatial shift keying (SSK) wireless communication systems in the presence of imperfect channel state information (CSI). Specifically, we analyze the average bit error probability (ABEP) of two RIS-SSK systems respectively based on intelligent reflection and blind reflection of RIS. For the intelligent RIS-SSK scheme, we first derive the conditional pairwise error probability of the composite channel through maximum likelihood (ML) detection. Subsequently, we derive the probability density function of the combined channel. Due to the intricacies of the composite channel formulation, an exact closed-form ABEP expression is unattainable through direct derivation. To this end, we resort to employing the Gaussian-Chebyshev quadrature method to estimate the results. In addition, we employ the Q-function approximation to derive the non-exact closed-form expression when CSI imperfections are present. For the blind RIS-SSK scheme, we derive both closed-form ABEP expression and asymptotic ABEP expression with imperfect CSI by adopting the ML detector. To offer deeper insights, we explore the impact of discrete reflection phase shifts on the performance of the RIS-SSK system. Lastly, we extensively validate all the analytical derivations using Monte Carlo simulations.Comment: arXiv admin note: text overlap with arXiv:2307.0199

ArSDM: Colonoscopy Images Synthesis with Adaptive Refinement Semantic Diffusion Models

Colonoscopy analysis, particularly automatic polyp segmentation and detection, is essential for assisting clinical diagnosis and treatment. However, as medical image annotation is labour- and resource-intensive, the scarcity of annotated data limits the effectiveness and generalization of existing methods. Although recent research has focused on data generation and augmentation to address this issue, the quality of the generated data remains a challenge, which limits the contribution to the performance of subsequent tasks. Inspired by the superiority of diffusion models in fitting data distributions and generating high-quality data, in this paper, we propose an Adaptive Refinement Semantic Diffusion Model (ArSDM) to generate colonoscopy images that benefit the downstream tasks. Specifically, ArSDM utilizes the ground-truth segmentation mask as a prior condition during training and adjusts the diffusion loss for each input according to the polyp/background size ratio. Furthermore, ArSDM incorporates a pre-trained segmentation model to refine the training process by reducing the difference between the ground-truth mask and the prediction mask. Extensive experiments on segmentation and detection tasks demonstrate the generated data by ArSDM could significantly boost the performance of baseline methods.Comment: Accepted by MICCAI-202

Chinese Medicinal Herbs for Childhood Pneumonia: A Systematic Review of Effectiveness and Safety

Objective. To assess the efficacy and safety of Chinese medicinal herbs for Childhood Pneumonia. Methods. We included randomized controlled trials (RCTs). The searched electronic databases included PubMed, the Cochrane Central Register of Controlled Trials, EMBASE, CBM, CNKI, and VIP. All studies included were assessed for quality and risk bias. Review Manager 5.1.6 software was used for data analyses, and the GRADEprofiler software was applied to classify the systematic review results. Results. Fourteen studies were identified (n=1.824). Chinese herbs may increase total effective rate (risk ratio (RR) 1.18; 95% confidence interval (CI), 1.11–1.26) and improve cough (total mean difference (MD), −2.18; 95% CI, (−2.66)–(−1.71)), fever (total MD, −1.85; 95% CI, (−2.29)–(−1.40)), rales (total MD, −1.53; 95% CI, (−1.84)–(−1.23)), and chest films (total MD, −3.10; 95% CI, (−4.11)–(−2.08)) in Childhood Pneumonia. Chinese herbs may shorten the length of hospital stay (total MD, −3.00; 95% CI, (−3.52)–(−2.48)), but no significant difference for adverse effects (RR, 0.39; 95% CI, 0.09–1.72) was identified. Conclusion. Chinese herbs may increase total effective rate and improve symptoms and signs. However, large, properly randomized, placebo-controlled, double-blind studies are required

Efficacy of modified thoraco-laparoscopic Ivor-Lewis versus traditional thoraco-laparoscopic Ivor-Lewis for esophageal cancer: Propensity score-matched analysis

ObjectiveTo compare the clinical results of the modified Ivor-Lewis procedure, which preserves the azygous vein, thoracic duct and surrounding tissues, with the traditional Ivor-Lewis procedure, which removes these tissues, for treating esophageal squamous cell carcinoma, and evaluating whether the azygous vein, thoracic duct and surrounding tissues are required to be removed for the surgery of esophageal cancer.MethodsTo retrospectively analyze the clinical data of patients suffering from esophageal cancer treated by thoracic-laparoscopic Ivor-Lewis procedure admitted to the Department of Thoracic Surgery of Gansu Provincial People’s Hospital from September 2017 to September 2019. According to the surgical method, they were divided into the modified thoracolaparoscopic Ivor-Lewis (modified group) and the traditional thoracolaparoscopic Ivor-Lewis (traditional group). Propensity score matching analysis (PSM) was applied to reduce the selection bias of confounding factors.ResultsA total of 245 patients who suffered from esophageal cancer and underwent thoracic-laparoscopic Ivor-Lewis were enrolled in the study. There were 124 cases in the modified group and 121 cases in the traditional group. The discrepancies in the age and T-stage among patients in the traditional and modified groups were statistically significant. After PSM, the above-mentioned factors became statistically insignificant. There were 86 patients in each group after PSM. Compared with the traditional group, the modified group has shorter operative time (p=0.007), less intraoperative bleeding (p=0.003) and less postoperative 3 days chest drainage(p=0.001), with a statistically significant difference. No significant difference in local recurrence (p=0.721) and distant metastasis (p=0.742) after surgery were found in the two groups, and the difference was not statistically significant. There was also no statistically significant difference in the 3-year postoperative survival rate (44.2% vs. 41.9%, p=0.605) between the modified and traditional groups.ConclusionThe modified Ivor-Lewis procedure, which preserves the azygous vein, thoracic duct, and surrounding tissue, reduces surgical trauma in esophageal cancer, has not increased postoperative recurrent metastases, while achieved the same long-term outcomes as expanded surgery