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1. Search for solar axions by Primakoff effect with the full dataset of the CDEX-1B Experiment

Author

Yang, L. T., Liu, S. K., Yue, Q., Kang, K. J., Li, Y. J., An, H. P., C., Greeshma, Chang, J. P., Chen, Y. H., Cheng, J. P., Dai, W. H., Deng, Z., Fang, C. H., Geng, X. P., Gong, H., Guo, Q. J., Guo, T., Guo, X. Y., He, L., He, J. R., Hu, J. W., Huang, H. X., Huang, T. C., Jiang, L., Karmakar, S., Li, H. B., Li, H. Y., Li, J. M., Li, J., Li, M. C., Li, Q. Y., Li, R. M. J., Li, X. Q., Li, Y. L., Liang, Y. F., Liao, B., Lin, F. K., Lin, S. T., Liu, J. X., Liu, Y. D., Liu, Y., Liu, Y. Y., Ma, H., Mao, Y. C., Nie, Q. Y., Pan, H., Qi, N. C., Ren, J., Ruan, X. C., Shen, M. B., Singh, M. K., Sun, T. X., Sun, W. L., Tang, C. J., Tian, Y., Wang, G. F., Wang, J. Z., Wang, L., Wang, Q., Wang, Y. F., Wang, Y. X., Wong, H. T., Wu, Y. C., Xing, H. Y., Xiong, K. Z., Xu, R., Xu, Y., Xue, T., Yan, Y. L., Yi, N., Yu, C. X., Yu, H. J., Zeng, M., Zeng, Z., Zhang, B. T., Zhang, F. S., Zhang, L., Zhang, P., Zhang, Z. H., Zhang, Z. Y., Zhao, J. Z., Zhao, K. K., Zhao, M. G., Zhou, J. F., Zhou, Z. Y., and Zhu, J. J.

Subjects
High Energy Physics - Experiment, High Energy Physics - Phenomenology, Physics - Instrumentation and Detectors
Abstract

We present the first limit on $g_{A\gamma}$ coupling constant using the Bragg-Primakoff conversion based on an exposure of 1107.5 kg days of data from the CDEX-1B experiment at the China Jinping Underground Laboratory. The data are consistent with the null signal hypothesis, and no excess signals are observed. Limits of the coupling $g_{A\gamma}<2.08\times10^{-9}$ GeV$^{-1}$ (95\% C.L.) are derived for axions with mass up to 100 eV/$c^2$. Within the hadronic model of KSVZ, our results exclude axion mass $>5.3~\rm{eV}/c^2$ at 95\% C.L., Comment: 7 pages, 5 figures

Published
2024

2. First Search for Light Fermionic Dark Matter Absorption on Electrons Using Germanium Detector in CDEX-10 Experiment

Author

Liu, J. X., Yang, L. T., Yue, Q., Kang, K. J., Li, Y. J., An, H. P., C., Greeshma, Chang, J. P., Chen, Y. H., Cheng, J. P., Dai, W. H., Deng, Z., Fang, C. H., Geng, X. P., Gong, H., Guo, Q. J., Guo, T., Guo, X. Y., He, L., He, J. R., Hu, J. W., Huang, H. X., Huang, T. C., Jiang, L., Karmakar, S., Li, H. B., Li, H. Y., Li, J. M., Li, J., Li, M. C., Li, Q. Y., Li, R. M. J., Li, X. Q., Li, Y. L., Liang, Y. F., Liao, B., Lin, F. K., Lin, S. T., Liu, S. K., Liu, Y. D., Liu, Y., Liu, Y. Y., Ma, H., Mao, Y. C., Nie, Q. Y., Pan, H., Qi, N. C., Ren, J., Ruan, X. C., Shen, M. B., Singh, M. K., Sun, T. X., Sun, W. L., Tang, C. J., Tian, Y., Wang, G. F., Wang, J. Z., Wang, L., Wang, Q., Wang, Y. F., Wang, Y. X., Wong, H. T., Wu, Y. C., Xing, H. Y., Xiong, K. Z., Xu, R., Xu, Y., Xue, T., Yan, Y. L., Yi, N., Yu, C. X., Yu, H. J., Zeng, M., Zeng, Z., Zhang, B. T., Zhang, F. S., Zhang, L., Zhang, P., Zhang, Z. H., Zhang, Z. Y., Zhao, J. Z., Zhao, K. K., Zhao, M. G., Zhou, J. F., Zhou, Z. Y., and Zhu, J. J.

Subjects
High Energy Physics - Experiment, High Energy Physics - Phenomenology, Physics - Instrumentation and Detectors
Abstract

We present the first results of the search for sub-MeV fermionic dark matter absorbed by electron targets of Germanium using the 205.4~kg$\cdot$day data collected by the CDEX-10 experiment, with the analysis threshold of 160~eVee. No significant dark matter (DM) signals over the background are observed. Results are presented as limits on the cross section of DM--electron interaction. We present new constraints of cross section in the DM range of 0.1--10 keV/$c^2$ for vector and axial-vector interaction. The upper limit on the cross section is set to be $\rm 5.5\times10^{-46}~cm^2$ for vector interaction, and $\rm 1.8\times10^{-46}~cm^2$ for axial-vector interaction at DM mass of 5 keV/$c^2$., Comment: 6 pages, 4 figures

Published
2024

4. Research on the Association Between Periodontitis and COPD

Author

Xiong K, Yang P, Cui Y, Li J, Li Y, and Tang B

Subjects
copd, microorganism, immune, inflammation, Diseases of the respiratory system, RC705-779
Abstract

Kaixin Xiong,1,&ast; Peng Yang,2,&ast; Yujia Cui,1 Jia Li,1 Yan Li,1 Boyu Tang1,3 1State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, People’s Republic of China; 2Department of Cardiovascular Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan, People’s Republic of China; 3State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Center for Oral Diseases & Department of Conservation Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Yan Li, State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, People’s Republic of China, Email feifeiliyan@163.com Boyu Tang, Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Center for Oral Diseases & Department of Conservation Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, People’s Republic of China, Email boyutang@126.comAbstract: Periodontitis is a common chronic bacteria-initiated inflammatory disease that is closely associated with various systemic diseases, including chronic obstructive pulmonary disease (COPD). Periodontitis and COPD share similar risk factors, pathology and microorganisms. Epidemiological and clinical research have shown positive correlation between the two diseases. Individuals with severe periodontitis had a higher risk of developing COPD. Moreover, the relative risk of COPD in severe periodontitis was much higher compared to people without periodontal disease and patients with mild to moderate periodontitis. COPD patients with periodontitis had a higher frequency of COPD exacerbation and periodontal treatment demonstrated some control of COPD. However, the nature of periodontitis affecting COPD still needs further exploration. Periodontitis caused microbial and immune imbalances of the lung through several aspects: (I) under periodontitis status, periodontal pathogens directly caused the lung inflammatory reaction after inhalation and colonization on the lung, (II) periodontitis status promoted the oral colonization of pneumonia-associated pathogens, (III) periodontitis status affected the respiratory epithelium structure and (IV) periodontitis status caused imbalances in neutrophils, macrophages and inflammatory cytokines. In this review, we conclude the association between periodontitis and COPD through several aspects and further discuss the potential mechanism by which periodontitis affects COPD.Plain Language Summary: Epidemiological and clinical research have shown positive correlation between periodontitis and COPD. Individuals with severe periodontitis had a higher risk of developing COPD. COPD patients with periodontitis had a higher frequency of COPD exacerbation. Meanwhile, periodontal treatment demonstrated some control of COPD. In this review, we concluded the association between periodontitis and further summarized that periodontitis caused microbial and immune imbalances of the lung through several aspects: (I) under periodontitis status, periodontal pathogens directly caused the lung inflammatory reaction after inhalation and colonization on the lung, (II) periodontitis status promoted the oral colonization of pneumonia-associated pathogens, (III) periodontitis status affected the respiratory epithelium structure and (IV) periodontitis status caused imbalances in neutrophils, macrophages and inflammatory cytokines.Keywords: COPD, microorganism, immune, inflammation

Published
2023

5. Latte-Mix: Measuring Sentence Semantic Similarity with Latent Categorical Mixtures

Author

Li, M., Bai, H., Tan, L., Xiong, K., and Lin, J.

Subjects
Computer Science - Computation and Language
Abstract

Measuring sentence semantic similarity using pre-trained language models such as BERT generally yields unsatisfactory zero-shot performance, and one main reason is ineffective token aggregation methods such as mean pooling. In this paper, we demonstrate under a Bayesian framework that distance between primitive statistics such as the mean of word embeddings are fundamentally flawed for capturing sentence-level semantic similarity. To remedy this issue, we propose to learn a categorical variational autoencoder (VAE) based on off-the-shelf pre-trained language models. We theoretically prove that measuring the distance between the latent categorical mixtures, namely Latte-Mix, can better reflect the true sentence semantic similarity. In addition, our Bayesian framework provides explanations for why models finetuned on labelled sentence pairs have better zero-shot performance. We also empirically demonstrate that these finetuned models could be further improved by Latte-Mix. Our method not only yields the state-of-the-art zero-shot performance on semantic similarity datasets such as STS, but also enjoy the benefits of fast training and having small memory footprints.

Published
2020

6. Circulating tumor DNA association with residual cancer burden after neoadjuvant chemotherapy in triple-negative breast cancer in TBCRC 030

Author

Parsons, H.A., Blewett, T., Chu, X., Sridhar, S., Santos, K., Xiong, K., Abramson, V.G., Patel, A., Cheng, J., Brufsky, A., Rhoades, J., Force, J., Liu, R., Traina, T.A., Carey, L.A., Rimawi, M.F., Miller, K.D., Stearns, V., Specht, J., Falkson, C., Burstein, H.J., Wolff, A.C., Winer, E.P., Tayob, N., Krop, I.E., Makrigiorgos, G.M., Golub, T.R., Mayer, E.L., and Adalsteinsson, V.A.

Published
2023
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7. Relation of Red Cell Distribution Width to Glucose Metabolism and Adverse Long-Term Prognosis in Patients with Acute Coronary Syndrome

Author

Xiong K, Xu C, Shou X, and Dong M

Subjects
red cell distribution width, hba1c, fasting blood glucose, percutaneous coronary intervention, acute coronary syndromes, major adverse cardiovascular events, Specialties of internal medicine, RC581-951
Abstract

Ke Xiong,1 Chenbo Xu,2 Xiling Shou,1 Mengya Dong1 1Department of Cardiovascular Medicine, Shaanxi Provincial People’s Hospital, Xi’an, 710068, People’s Republic of China; 2Department of Cardiovascular Medicine, First Affiliated Hospital of Medical College, Xi’an Jiaotong University, Xi’an, 710061, People’s Republic of ChinaCorrespondence: Mengya Dong, Department of Cardiovascular Medicine, Shaanxi Provincial People’s Hospital, 256 West Youyi Road, Xi’an, Shaanxi, 710068, People’s Republic of China, Tel +86– 15802943974, Email 405895903@qq.comIntroduction: Red cell distribution width (RDW) reflects the heterogeneity of red blood cell size. However, few studies examined whether RDW is related to glucose metabolism indices, such as fasting blood glucose (FBG) and hemoglobin A1c (HbA1c), diabetic mellitus (DM) state or long-term outcomes of acute coronary syndrome (ACS) patients.Methods and Results: A total of 448 consecutive patients with ACS were enrolled in this study. All patients were followed up for major cardiovascular adverse events (MACEs), and the mean follow-up was 952 days. Linear regression analysis showed that RDW inversely correlated with FBG but not HbA1c or DM. Kaplan-Meier survival curve analysis demonstrated that higher RDW levels were significantly positively associated with MACEs in the whole study population and the ACS patients with high FBG but not the low FBG group. Cox multivariate regression analysis revealed the independent function of RDW on MACEs in all ACS patients and ACS patients with high FBG. The receiver operating characteristic (ROC) curve demonstrated the optimal cutoff value of RDW for MACEs.Conclusion: We first reported that higher RDW was associated with decreased FBG but not HbA1c or DM and an increased risk of MACEs in patients with ACS. This relationship was also found in ACS patients with higher FBG levels but not in ACS patients with lower FBG.Keywords: red cell distribution width, HbA1c, fasting blood glucose, percutaneous coronary intervention, acute coronary syndromes, major adverse cardiovascular events

Published
2023

8. Decoding the Key Functional Combined Components Group and Uncovering the Molecular Mechanism of Longdan Xiegan Decoction in Treating Uveitis

Author

Zheng YX, Wang KX, Chen SJ, Liao MX, Chen YP, Guan DG, Wu J, and Xiong K

Subjects
traditional chinese medicine (tcm), uveitis, foundational acting communities (facs), mechanisms, network analysis, Therapeutics. Pharmacology, RM1-950
Abstract

Yi-Xu Zheng,1 Ke-Xin Wang,2– 4 Si-Jin Chen,5 Mu-Xi Liao,6 Yu-Peng Chen,3,4 Dao-Gang Guan,3,4 Jing Wu,7 Ke Xiong1 1Department of Ophthalmology, Nanfang Hospital, Southern Medical University, Guangzhou, People’s Republic of China; 2Neurosurgery Center, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Cerebrovascular Surgery, Engineering Technology Research Center of Education Ministry of China on Diagnosis and Treatment of Cerebrovascular Disease, Zhujiang Hospital, Southern Medical University, Guangzhou, People’s Republic of China; 3Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, People’s Republic of China; 4Guangdong Province Key Laboratory of Single Cell Technology and Application, Southern Medical University, Guangzhou, People’s Republic of China; 5Department of Medical Imaging Center, Nanfang Hospital, Southern Medical University, Guangzhou, People’s Republic of China; 6The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510405, People’s Republic of China; 7Huiqiao Medical Center, Nanfang Hospital, Southern Medical University, Guangzhou, People’s Republic of ChinaCorrespondence: Jing Wu; Ke Xiong, Email wujing@smu.edu.cn; xiongk@smu.edu.cnObjective: Longdan Xiegan Decoction (LXD) is a famous herbal formula in China. It has been proved that LXD has been shown to have a significant inhibitory effect on suppresses the inflammatory cells associated with uveitis. However, the key functional combination of component groups and their possible mechanisms remain unclear.Methods: The community detecting model of the network, the functional response space, and reverse prediction model were utilized to decode the key components group (KCG) and possible mechanism of LXD in treating uveitis. Finally, MTT assay, NO assay and ELISA assay were applied to verify the effectiveness of KCG and the accuracy of our strategy.Results: In the components-targets-pathogenic genes-disease (CTP) network, a combination of Huffman coding and random walk algorithm was used and eight foundational acting communities (FACs) were discovered with important functional significance. Verification has shown that FACs can represent the corresponding C-T network for treating uveitis. A novel node importance calculation method was designed to construct the functional response space and pick out 349 effective proteins. A total of 54 components were screened and defined as KCG. The pathway enrichment results showed that KCG and their targets enriched signal pathways of IL-17, Toll-like receptor, and T cell receptor played an important role in the pathogenesis of uveitis. Furthermore, experimental verification results showed that important KCG quercetin and sitosterol markedly inhibited the production of nitric oxide and significantly regulated the level of TNF-α and IFN-γ in Lipopolysaccharide-induced RAW264.7 cells.Discussion: In this research, we decoded the potential mechanism of the multi-components-genes-pathways of LXD’s pharmacological action mode against uveitis based on an integrated pharmacology approach. The results provided a new perspective for the future studies of the anti-uveitis mechanism of traditional Chinese medicine.Keywords: traditional Chinese medicine, TCM, uveitis, foundational acting communities, FACs, mechanisms, network analysis

Published
2022

10. Assessment of options for small-scale groundwater irrigation in Lao PDR

Author

Pavelic, P., primary, Suhardiman, D., additional, Keovilignavong, O., additional, Clément, C., additional, Vinckevleugel, J., additional, Bohsung, S.M., additional, Xiong, K., additional, Valee, L., additional, Viossanges, M., additional, Douangsavanh, S., additional, Sotoukee, T., additional, Villholth, K.G., additional, Shivakoti, B.R., additional, and Vongsathiane, K., additional

Published
2022
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12. Enhancing Cancer Immunotherapy Treatment Goals by Using Nanoparticle Delivery System

Author

Muluh TA, Chen Z, Li Y, Xiong K, Jin J, Fu S, and Wu J

Subjects
tumor immunotherapy, immune system, nanoparticles, drug delivery, drug release., Medicine (General), R5-920
Abstract

Tobias Achu Muluh,1,* Zhuo Chen,1,* Yi Li,1,* Kang Xiong,1 Jing Jin,1 ShaoZhi Fu,1– 3 JingBo Wu1– 3 1Department of Oncology, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, People’s Republic of China; 2Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province, Luzhou, 646000, Sichuan, People’s Republic of China; 3Department of Oncology, Academician (Expert) Workstation of Sichuan Province, Luzhou, Sichuan, 646000, People’s Republic of China*These authors contributed equally to this workCorrespondence: ShaoZhi Fu; JingBo WuDepartment of Oncology, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, People’s Republic of ChinaTel/Fax +86 8303165696Email shaozhifu513@163.com; wjb6147@163.comAbstract: Recently, there has been an incredible increase in research about the abnormal growth of cells (neoplasm), focusing on the management, treatment and preventing reoccurrence. It has been understood that the natural defense system, composed of a variety of immune defensive cells, does not just limit its function in eliminating neoplastic cells, but also controls the growth and spread of tumor cells of different kinds to other parts of the body. Cancer immunotherapy, is a cancer treatment plan that educates the body’s defensive system to forestall, control, and eliminate tumor cells. The effectiveness of immunotherapy is achieved, to its highest efficacy, by the use of nanoparticles (NPs) for precise and timely delivery of immunotherapies to specific targeted neoplasms, with less or no harm to the healthy cells. Immunotherapies have been affirmed in clinical trials as a cancer regimen for various types of cancers, the side effects resulting from imprecise and non-targeted conveyance is well managed with the use of nanoparticles. Nonetheless, we will concentrate on enhancing cancer immunotherapy approaches by the use of nanoparticles for the productivity of antitumor immunity. Nanoparticles will be presented and utilized as an objective immunotherapy delivery system for high exactness and are thus a promising methodology for cancer treatment.Keywords: tumor immunotherapy, immune system, nanoparticles, drug delivery, drug release

Published
2021

15. Osteochondral repair using scaffolds with gradient pore sizes constructed with silk fibroin, chitosan, and nano-hydroxyapatite

Author

Xiao H, Huang W, Xiong K, Ruan S, Yuan C, Mo G, Tian R, Zhou S, She R, Ye P, Liu B, and Deng J

Subjects
silk fibroin, chitosan, nano-hydroxyapatite, osteochondral, gradient pore size, scaffold, bone marrow mesenchymal stem cells, Medicine (General), R5-920
Abstract

Hongli Xiao,1,* Wenliang Huang,1,* Kun Xiong,1 Shiqiang Ruan,1 Cheng Yuan,1 Gang Mo,1 Renyuan Tian,1 Sirui Zhou,1 Rongfeng She,2 Peng Ye,3 Bin Liu,4 Jiang Deng1 1Department of Orthopedics, Third Affiliated Hospital of Zunyi Medical University, Zunyi 563000, Guizhou Province, People’s Republic of China; 2Department of Orthopedics, Guizhou Province People’s Hospital, Guiyang 550002, Guizhou Province, People’s Republic of China; 3Emergency and Trauma Ward, Affiliated Hospital of Zunyi Medical University, Zunyi 563000, Guizhou Province, People’s Republic of China; 4Surgical Laboratory, Zunyi Medical University, Zunyi 563000, Guizhou Province, People’s Republic of China *These authors contributed equally to this work Background: One of the main problems associated with the development of osteochondral reparative materials is that the accurate imitation of the structure of the natural osteochondral tissue and fabrication of a suitable scaffold material for osteochondral repair are difficult. The long-term outcomes of single- or bilayered scaffolds are often unsatisfactory because of the absence of a progressive osteochondral structure. Therefore, only scaffolds with gradient pore sizes are suitable for osteochondral repair to achieve better proliferation and differentiation of the stem cells into osteochondral tissues to complete the repair of defects. Methods: A silk fibroin (SF) solution, chitosan (CS) solution, and nano-hydroxyapatite (nHA) suspension were mixed at the same weight fraction to obtain osteochondral scaffolds with gradient pore diameters by centrifugation, freeze-drying, and chemical cross-linking. Results: The scaffolds prepared in this study are confirmed to have a progressive structure starting from the cartilage layer to bone layer, similar to that of the normal osteochondral tissues. The prepared scaffolds are cylindrical in shape and have high internal porosity. The structure consists of regular and highly interconnected pores with a progressively increasing pore distribution as well as a progressively changing pore diameter. The scaffold strongly absorbs water, and has a suitable degradation rate, sufficient space for cell growth and proliferation, and good resistance to compression. Thus, the scaffold can provide sufficient nutrients and space for cell growth, proliferation, and migration. Further, bone marrow mesenchymal stem cells seeded onto the scaffold closely attach to the scaffold and stably grow and proliferate, indicating that the scaffold has good biocompatibility with no cytotoxicity. Conclusion: In brief, the physical properties and biocompatibility of our scaffolds fully comply with the requirements of scaffold materials required for osteochondral tissue engineering, and they are expected to become a new type of scaffolds with gradient pore sizes for osteochondral repair. Keywords: tissue engineering, bone marrow mesenchymal stem cells, bioscaffolds, osteochondral defect

Published
2019

21. Incidence, causes and risk factors of vision loss in rural Southern China: 6-year follow-up of the Yangxi Eye Study

Author

Zhao, X, Lin, J, Yu, S, Xie, L, Jin, L, Xiong, K, Tsui, C-K, Xu, Y, Wu, B, Liu, B, Wang, W, Congdon, N, Huang, W, He, M, Liang, X, Zhao, X, Lin, J, Yu, S, Xie, L, Jin, L, Xiong, K, Tsui, C-K, Xu, Y, Wu, B, Liu, B, Wang, W, Congdon, N, Huang, W, He, M, and Liang, X

Abstract

PURPOSE: To report the 6-year incidence, causes and risk factors for vision loss (visual impairment (VI) and blindness), among elderly adults in rural southern China. METHODS: Population-based, cohort study. Initiated in 2014, the study recruited participants aged 50 and older using random cluster sampling from Yangxi County. All eligible participants were invited to attend interviews and comprehensive eye examinations at the 6-year follow-up between November 2020 and March 2021. The WHO categories of vision loss were used to define incident cases of VI (3/60≤VA <6/12), moderate-to-severe VI (MSVI) (3/60≤VA<6/18) and blindness (VA <3/60) in the better-seeing eye. RESULTS: Among the 5825 baseline participants, 3187 (64.4%) of 4946 surviving subjects participated in the 6-year follow-up. Based on presenting and best-corrected VA, respectively, the crude incidence rate of blindness was 0.8% (95% CI 0.5% to 1.1%) vs 0.3% (95% CI 0.1% to 0.5%), for MSVI 6.7% (95% CI 5.7% to 7.6%) vs 4.6% (95% CI 3.8% to 5.4%) and for any VI 16.1% (95% CI 14.5% to 17.6%) vs 12.9% (95% CI 11.6% to 14.1%). Cataract (48.3%) and refractive errors (44.4%) were the most common causes of vision loss. Factors significantly associated with greater incident vision loss were older age, female sex, less education, living alone and longer axial length (all p<0.05). CONCLUSIONS: Substantial work is still required to reduce avoidable vision loss in rural China. Screening outreach and efforts to improve awareness which target the poorer and less educated are urgently needed to reduce the growing unmet need for eye care due to ageing.

Published
2022

27. Molecular beam epitaxy growth of monolayer hexagonal MnTe2 on Si(111) substrate*

Author

Lu, S, primary, Peng, K, additional, Wang, P D, additional, Chen, A X, additional, Ren, W, additional, Fang, X W, additional, Wu, Y, additional, Li, Z Y, additional, Li, H F, additional, Cheng, F Y, additional, Xiong, K L, additional, Yang, J Y, additional, Wang, J Z, additional, Ding, S A, additional, Jiang, Y P, additional, Wang, L, additional, Li, Q, additional, Li, F S, additional, and Chi, L F, additional

Published
2021
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28. Chord: Identifying Doublets in Single-Cell RNA Sequencing Data by an Ensemble Machine Learning Algorithm

Author

Li G, Karsten Kristiansen, Yang H, Xiong K, Yin J, and Zhou H

Subjects
Flexibility (engineering), business.industry, Computer science, media_common.quotation_subject, Stability (learning theory), Ensemble learning, Synthetic data, Adaptability, Task (computing), Software, business, Chord (peer-to-peer), Algorithm, media_common
Abstract

SummaryHigh-throughput single-cell RNA sequencing (scRNA-seq) is a popular method, but it is accompanied by doublet rate problems that disturb the downstream analysis. Several computational approaches have been developed to detect doublets. However, most of these methods have good performance in some datasets but lack stability in others; thus, it is difficult to regard a single method as the gold standard for each scenario, and it is a difficult and time-consuming task for researcher to choose the most appropriate software. To address these issues, we propose Chord which implements a machine learning algorithm that integrates multiple doublet detection methods. Chord had a higher accuracy and stability than the individual approaches on different datasets containing real and synthetic data. Moreover, Chord was designed with a modular architecture port, which has high flexibility and adaptability to the incorporation of any new tools. Chord is a general solution to the doublet detection problem.

Published
2021

34. UAV-aided Wireless Power Transfer and Data Collection in Rician Fading

Author

Liu, Y., Xiong, K., Lu, Y., Ni, Q., Fan, P., Letaief, K.B., Liu, Y., Xiong, K., Lu, Y., Ni, Q., Fan, P., and Letaief, K.B.

Abstract

A UAV-aided wireless power transfer and data collection network is studied, where it is assumed that when the harvested energy at the sensor node (SN) cannot surpass its circuit activation threshold or the received data rate at UAV falls below a minimal required rate threshold, the information outage occurs. The closed-form expressions of energy outage probability and rate outage probability are derived at first, and then the overall outage probability and coverage performance of the system are analyzed. Based on which, an optimization problem is formulated to minimize the overall outage probability by optimizing UAV’s elevation angle and the time splitting (TS) factor. Since the problem is non-convex and has no known solution, an alternating optimization (AO)-based algorithm with Golden-section (GS) based linear search method is designed to find the global optimal solution. In order to explore the maximum coverage area of the UAV for a given tolerable outage probability, another optimization problem is also formulated to maximize the coverage range by optimizing UAV’s elevation angle. By using Karush-Kuhn-Tucker (KKT) conditions, the closed-form solution of the optimal elevation angle for maximizing the coverage area is derived. Monte Carlo simulations verify the accuracy of the derived closed-form expression of the overall outage probability and the semi-closed-form expressions of the optimum UAV’s elevation angle and TS factor. It shows that there exist a unique optimum elevation angle and the TS factor to achieve the minimum overall outage probability, and significant performance gain can be obtained by using our proposed optimization scheme. The developed theoretical results can be useful to the design of UAV-aided wireless communication systems with wireless power transfer.

Published
2021

35. AoI-Minimal Trajectory Planning and Data Collection in UAV-Assisted Wireless Powered IoT Networks

Author

Hu, H., Xiong, K., Qu, G., Ni, Q., Fan, P., Letaief, K.B., Hu, H., Xiong, K., Qu, G., Ni, Q., Fan, P., and Letaief, K.B.

Abstract

This article investigates the unmanned aerial vehicle (UAV)-assisted wireless powered Internet-of-Things system, where a UAV takes off from a data center, flies to each of the ground sensor nodes (SNs) in order to transfer energy and collect data from the SNs, and then returns to the data center. For such a system, an optimization problem is formulated to minimize the average Age of Information (AoI) of the data collected from all ground SNs. Since the average AoI depends on the UAV's trajectory, the time required for energy harvesting (EH) and data collection for each SN, these factors need to be optimized jointly. Moreover, instead of the traditional linear EH model, we employ a nonlinear model because the behavior of the EH circuits is nonlinear by nature. To solve this nonconvex problem, we propose to decompose it into two subproblems, i.e., a joint energy transfer and data collection time allocation problem and a UAV's trajectory planning problem. For the first subproblem, we prove that it is convex and give an optimal solution by using Karush-Kuhn-Tucker (KKT) conditions. This solution is used as the input for the second subproblem, and we solve optimally it by designing dynamic programming (DP) and ant colony (AC) heuristic algorithms. The simulation results show that the DP-based algorithm obtains the minimal average AoI of the system, and the AC-based heuristic finds solutions with near-optimal average AoI. The results also reveal that the average AoI increases as the flying altitude of the UAV increases and linearly with the size of the collected data at each ground SN.

Published
2021

38. Finite-time synchronization of fully complex-valued networks with or without time-varying delays via intermittent control

Author

Xiong K, Yu J, Hu C, Wen S, and Jiang H

Subjects
08 Information and Computing Sciences, 09 Engineering, 17 Psychology and Cognitive Sciences, Artificial Intelligence & Image Processing
Abstract

© 2020 Elsevier B.V. This paper explores finite-time (F-T) synchronization for a type of fully complex-valued (C-V) networks with or without delays by proposing intermittent control schemes but without using the ordinary separation technique. Above all, the vector signum function in complex field is proposed as the generalization of real-valued counterpart, which is critical to the control design in complex field and the construction of Lyapunov functions. To realize F-T synchronization, several complex-valued intermittent controllers, only dependent of the information of controlled nodes, are designed on the addressed complex-valued networks, which are different from the design on the divided real-valued subsystems. In the theoretical analysis, some nontrivial Lyapunov functionals and functions are constructed by virtue of the proposed signum function and some inequalities are developed in complex domain to establish criteria of F-T synchronization. Finally, some numerical examples are performed to reveal the effectiveness of the derived results and the practicality of the proposed control strategies.

Published
2020

41. Detection of satellite attitude sensor faults using the UKF

Author

Xiong, K., Chan, C.W., and Zhang, H.Y.

Subjects
Sensors -- Design and construction, Kalman filtering -- Evaluation, Gaussian processes -- Evaluation, Artificial satellites -- Design and construction, Aerospace and defense industries, Business, Computers, Electronics, Electronics and electrical industries
Abstract

A novel fault detection (FD) method for nonlinear systems using the residuals generated by the unscented Kalman filter (UKF) is proposed. The errors of the UKF are derived and sufficient conditions for the convergence of the UKF are presented. As the local approach is a powerful statistical technique for detecting changes in the mean of a Gaussian process, it is used to devise a hypothesis test to detect faults from residuals obtained from the UKF. Further, it is demonstrated that the selection of a sample number is important in improving the performance of the local approach. To illustrate the implementation and performance of the proposed technique, it is applied to detect sensor faults in the measurement of satellite attitude.

Published
2007

42. UAV-Assisted Wireless Powered Cooperative Mobile Edge Computing:Joint Offloading, CPU Control, and Trajectory Optimization

Author

Liu, Y., Xiong, K., Ni, Q., Fan, P., Letaief, K.B., Liu, Y., Xiong, K., Ni, Q., Fan, P., and Letaief, K.B.

Abstract

This article investigates the unmanned-aerial-vehicle (UAV)-enabled wireless powered cooperative mobile edge computing (MEC) system, where a UAV installed with an energy transmitter (ET) and an MEC server provides both energy and computing services to sensor devices (SDs). The active SDs desire to complete their computing tasks with the assistance of the UAV and their neighboring idle SDs that have no computing task. An optimization problem is formulated to minimize the total required energy of UAV by jointly optimizing the CPU frequencies, the offloading amount, the transmit power, and the UAV’s trajectory. To tackle the nonconvex problem, a successive convex approximation (SCA)-based algorithm is designed. Since it may be with relatively high computational complexity, as an alternative, a decomposition and iteration (DAI)-based algorithm is also proposed. The simulation results show that both proposed algorithms converge within several iterations, and the DAI-based algorithm achieve the similar minimal required energy and optimized trajectory with the SCA-based one. Moreover, for a relatively large amount of data, the SCA-based algorithm should be adopted to find an optimal solution, while for a relatively small amount of data, the DAI-based algorithm is a better choice to achieve smaller computing energy consumption. It also shows that the trajectory optimization plays a dominant factor in minimizing the total required energy of the system and optimizing acceleration has a great effect on the required energy of the UAV. Additionally, by jointly optimizing the UAV’s CPU frequencies and the amount of bits offloaded to UAV, the minimal required energy for computing can be greatly reduced compared to other schemes and by leveraging the computing resources of idle SDs, the UAV’s computing energy can also be greatly reduced.

Published
2020

43. UAV-Assisted Wireless Powered Cooperative Mobile Edge Computing : Joint Offloading, CPU Control, and Trajectory Optimization

Author

Liu, Y., Xiong, K., Ni, Q., Fan, P., Letaief, K.B., Liu, Y., Xiong, K., Ni, Q., Fan, P., and Letaief, K.B.

Abstract

This article investigates the unmanned-aerial-vehicle (UAV)-enabled wireless powered cooperative mobile edge computing (MEC) system, where a UAV installed with an energy transmitter (ET) and an MEC server provides both energy and computing services to sensor devices (SDs). The active SDs desire to complete their computing tasks with the assistance of the UAV and their neighboring idle SDs that have no computing task. An optimization problem is formulated to minimize the total required energy of UAV by jointly optimizing the CPU frequencies, the offloading amount, the transmit power, and the UAV’s trajectory. To tackle the nonconvex problem, a successive convex approximation (SCA)-based algorithm is designed. Since it may be with relatively high computational complexity, as an alternative, a decomposition and iteration (DAI)-based algorithm is also proposed. The simulation results show that both proposed algorithms converge within several iterations, and the DAI-based algorithm achieve the similar minimal required energy and optimized trajectory with the SCA-based one. Moreover, for a relatively large amount of data, the SCA-based algorithm should be adopted to find an optimal solution, while for a relatively small amount of data, the DAI-based algorithm is a better choice to achieve smaller computing energy consumption. It also shows that the trajectory optimization plays a dominant factor in minimizing the total required energy of the system and optimizing acceleration has a great effect on the required energy of the UAV. Additionally, by jointly optimizing the UAV’s CPU frequencies and the amount of bits offloaded to UAV, the minimal required energy for computing can be greatly reduced compared to other schemes and by leveraging the computing resources of idle SDs, the UAV’s computing energy can also be greatly reduced.

Published
2020

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