111 results on '"Zhening Li"'
Search Results
2. Predictive Chemistry Augmented with Text Retrieval.
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Yujie Qian, Zhening Li, Zhengkai Tu, Connor W. Coley, and Regina Barzilay
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- 2023
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3. Unsupervised Feature Selection via Graph Regularized Nonnegative CP Decomposition
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Bilian Chen, Jiewen Guan, and Zhening Li
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Computational Theory and Mathematics ,Artificial Intelligence ,Applied Mathematics ,Computer Vision and Pattern Recognition ,Software - Abstract
Unsupervised feature selection has attracted remarkable attention recently. With the development of data acquisition technology, multi-dimensional tensor data has been appeared in enormous real-world applications. However, most existing unsupervised feature selection methods are non-tensor-based which results the vectorization of tensor data as a preprocessing step. This seemingly ordinary operation has led to an unnecessary loss of the multi-dimensional structural information and eventually restricted the quality of the selected features. To overcome the limitation, in this paper, we propose a novel unsupervised feature selection model: Nonnegative tensor CP (CANDECOMP/PARAFAC) decomposition based Unsupervised Feature Selection, CPUFS for short. In specific, we devise new tensor-oriented linear classifier and feature selection matrix for CPUFS. In addition, CPUFS simultaneously conducts graph regularized nonnegative CP decomposition and newly-designed tensor-oriented pseudo label regression and feature selection to fully preserve the multi-dimensional data structure. To solve the CPUFS model, we propose an efficient iterative optimization algorithm with theoretically guaranteed convergence, whose computational complexity scales linearly in the number of features. A variation of the CPUFS model by incorporating nonnegativity into the linear classifier, namely CPUFSnn, is also proposed and studied. Experimental results on ten real-world benchmark datasets demonstrate the effectiveness of both CPUFS and CPUFSnn over the state-of-the-arts.
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- 2023
4. APPROXIMATING TENSOR NORMS VIA SPHERE COVERING: BRIDGING THE GAP BETWEEN PRIMAL AND DUAL.
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SIMAI HE, HAODONG HU, BO JIANG, and ZHENING LI
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SPHERES ,MATRIX norms ,APPROXIMATION algorithms ,DETERMINISTIC algorithms ,HYPERCUBES - Abstract
The matrix spectral norm and nuclear norm appear in enormous applications. The generalization of these norms to higher-order tensors is becoming increasingly important, but unfortunately they are NP-hard to compute or even approximate. Although the two norms are dual to each other, the best-known approximation bound achieved by polynomial-time algorithms for the tensor nuclear norm is worse than that for the tensor spectral norm. In this paper, we bridge this gap by proposing deterministic algorithms with the best bound for both tensor norms. Our methods not only improve the approximation bound for the nuclear norm but also are data independent and easily implementable compared to existing approximation methods for the tensor spectral norm. The main idea is to construct a selection of unit vectors that can approximately represent the unit sphere, in other words, a collection of spherical caps to cover the sphere. For this purpose, we explicitly construct several collections of spherical caps for sphere covering with adjustable parameters for different levels of approximations and cardinalities. These readily available constructions are of independent interest, as they provide a powerful tool for various decision-making problems on spheres and related problems. We believe the ideas of constructions and the applications to approximate tensor norms can be useful to tackle optimization problems over other sets, such as the binary hypercube. [ABSTRACT FROM AUTHOR]
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- 2023
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5. Neurostructural subgroup in 4291 individuals with schizophrenia identified using the subtype and stage inference algorithm
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Yuchao Jiang, Cheng Luo, Jijun Wang, Lena Palaniyappan, Xiao Chang, Shitong Xiang, Jie Zhang, Mingjun Duan, Huan Huang, Christian Gaser, Kiyotaka Nemoto, Kenichiro Miura, Ryota Hashimoto, Lars T. Westlye, Genevieve Richard, Sara Fernandez-Cabello, Nadine Parker, Ole A. Andreassen, Tilo Kircher, Igor Nenadić, Frederike Stein, Florian Thomas-Odenthal, Lea Teutenberg, Paula Usemann, Udo Dannlowski, Tim Hahn, Dominik Grotegerd, Susanne Meinert, Rebekka Lencer, Yingying Tang, Tianhong Zhang, Chunbo Li, Weihua Yue, Yuyanan Zhang, Xin Yu, Enpeng Zhou, Ching-Po Lin, Shih-Jen Tsai, Amanda L. Rodrigue, David Glahn, Godfrey Pearlson, John Blangero, Andriana Karuk, Edith Pomarol-Clotet, Raymond Salvador, Paola Fuentes-Claramonte, María Ángeles Garcia-León, Gianfranco Spalletta, Fabrizio Piras, Daniela Vecchio, Nerisa Banaj, Jingliang Cheng, Zhening Liu, Jie Yang, Ali Saffet Gonul, Ozgul Uslu, Birce Begum Burhanoglu, Aslihan Uyar Demir, Kelly Rootes-Murdy, Vince D. Calhoun, Kang Sim, Melissa Green, Yann Quidé, Young Chul Chung, Woo-Sung Kim, Scott R. Sponheim, Caroline Demro, Ian S. Ramsay, Felice Iasevoli, Andrea de Bartolomeis, Annarita Barone, Mariateresa Ciccarelli, Arturo Brunetti, Sirio Cocozza, Giuseppe Pontillo, Mario Tranfa, Min Tae M. Park, Matthias Kirschner, Foivos Georgiadis, Stefan Kaiser, Tamsyn E. Van Rheenen, Susan L. Rossell, Matthew Hughes, William Woods, Sean P. Carruthers, Philip Sumner, Elysha Ringin, Filip Spaniel, Antonin Skoch, David Tomecek, Philipp Homan, Stephanie Homan, Wolfgang Omlor, Giacomo Cecere, Dana D. Nguyen, Adrian Preda, Sophia I. Thomopoulos, Neda Jahanshad, Long-Biao Cui, Dezhong Yao, Paul M. Thompson, Jessica A. Turner, Theo G. M. van Erp, Wei Cheng, ENIGMA Schizophrenia Consortium, Jianfeng Feng, and ZIB Consortium
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Science - Abstract
Abstract Machine learning can be used to define subtypes of psychiatric conditions based on shared biological foundations of mental disorders. Here we analyzed cross-sectional brain images from 4,222 individuals with schizophrenia and 7038 healthy subjects pooled across 41 international cohorts from the ENIGMA, non-ENIGMA cohorts and public datasets. Using the Subtype and Stage Inference (SuStaIn) algorithm, we identify two distinct neurostructural subgroups by mapping the spatial and temporal ‘trajectory’ of gray matter change in schizophrenia. Subgroup 1 was characterized by an early cortical-predominant loss with enlarged striatum, whereas subgroup 2 displayed an early subcortical-predominant loss in the hippocampus, striatum and other subcortical regions. We confirmed the reproducibility of the two neurostructural subtypes across various sample sites, including Europe, North America and East Asia. This imaging-based taxonomy holds the potential to identify individuals with shared neurobiological attributes, thereby suggesting the viability of redefining existing disorder constructs based on biological factors.
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- 2024
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6. EXTREME RATIO BETWEEN SPECTRAL AND FROBENIUS NORMS OF NONNEGATIVE TENSORS.
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SHENGYU CAO, SIMAI HE, ZHENING LI, and ZHEN WANG
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MULTILINEAR algebra ,TENSOR algebra ,NONNEGATIVE matrices - Abstract
One of the fundamental problems in multilinear algebra, the minimum ratio between the spectral and Frobenius norms of tensors, has received considerable attention in recent years. While most values are unknown for real and complex tensors, the asymptotic order of magnitude and tight lower bounds have been established. However, little is known about nonnegative tensors. In this paper, we present an almost complete picture of the ratio for nonnegative tensors. In particular, we provide a tight lower bound that can be achieved by a wide class of nonnegative tensors under a simple necessary and sufficient condition, which helps to characterize the extreme tensors and obtain results such as the asymptotic order of magnitude. We show that the ratio for symmetric tensors is no more than that for general tensors multiplied by a constant depending only on the order of tensors, hence determining the asymptotic order of magnitude for real, complex, and nonnegative symmetric tensors. We also find that the ratio is in general different from the minimum ratio between the Frobenius and nuclear norms for nonnegative tensors, a sharp contrast to the case for real tensors and complex tensors. [ABSTRACT FROM AUTHOR]
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- 2023
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7. Robust Feature Extraction via ℓ∞-Norm based Nonnegative Tucker Decomposition
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Bilian Chen, Jiewen Guan, Zhening Li, and Zhehao Zhou
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Media Technology ,Electrical and Electronic Engineering - Published
- 2023
8. On decompositions and approximations of conjugate partial-symmetric tensors
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Taoran Fu, Zhening Li, and Bo Jiang
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Computational Mathematics ,Pure mathematics ,Algebra and Number Theory ,Optimization problem ,Generalization ,Numerical analysis ,Convex optimization ,Theory of computation ,Computer Science::Programming Languages ,Tensor ,Quadratic programming ,Hermitian matrix ,Mathematics - Abstract
Hermitian matrices have played an important role in matrix theory and complex quadratic optimization. The high-order generalization of Hermitian matrices, conjugate partial-symmetric (CPS) tensors, have shown growing interest recently in tensor theory and computation, particularly in application-driven complex polynomial optimization problems. In this paper, we study CPS tensors with a focus on ranks, computing rank-one decompositions and approximations, as well as their applications. We prove constructively that any CPS tensor can be decomposed into a sum of rank-one CPS tensors, which provides an explicit method to compute such rank-one decompositions. Three types of ranks for CPS tensors are defined and shown to be different in general. This leads to the invalidity of the conjugate version of Comon’s conjecture. We then study rank-one approximations and matricizations of CPS tensors. By carefully unfolding CPS tensors to Hermitian matrices, rank-one equivalence can be preserved. This enables us to develop new convex optimization models and algorithms to compute best rank-one approximations of CPS tensors. Numerical experiments from data sets in radar wave form design, elasticity tensor, and quantum entanglement are performed to justify the capability of our methods.
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- 2021
9. Circulating fatty acids and risk of hepatocellular carcinoma and chronic liver disease mortality in the UK Biobank
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Zhening Liu, Hangkai Huang, Jiarong Xie, Yingying Xu, and Chengfu Xu
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Science - Abstract
Abstract Nuclear magnetic resonance (NMR)-based plasma fatty acids are objective biomarkers of many diseases. Herein, we aim to explore the associations of NMR-based plasma fatty acids with the risk of hepatocellular carcinoma (HCC) and chronic liver disease (CLD) mortality in 252,398 UK Biobank participants. Here we show plasma levels of n-3 poly-unsaturated fatty acids (PUFA) and n-6 PUFA are negatively associated with the risk of incident HCC [HRQ4vsQ1: 0.48 (95% CI: 0.33–0.69) and 0.48 (95% CI: 0.28–0.81), respectively] and CLD mortality [HRQ4vsQ1: 0.21 (95% CI: 0.13–0.33) and 0.15 (95% CI: 0.08–0.30), respectively], whereas plasma levels of saturated fatty acids are positively associated with these outcomes [HRQ4vsQ1: 3.55 (95% CI: 2.25–5.61) for HCC and 6.34 (95% CI: 3.68–10.92) for CLD mortality]. Furthermore, fibrosis stage significantly modifies the associations between PUFA and CLD mortality. This study contributes to the limited prospective evidence on the associations between plasma-specific fatty acids and end-stage liver outcomes.
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- 2024
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10. Factor analysis and evaluation of one-year test-retest reliability of the 33-item Childhood Trauma Questionnaire in Chinese adolescents
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Jiamei Zhang, Zhipeng Wu, Min Chen, Yan Gao, Zhening Liu, Yicheng Long, and Xudong Chen
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Childhood Trauma Questionnaire ,childhood trauma ,factor structure ,test-retest reliability ,childhood abuse ,Psychology ,BF1-990 - Abstract
The 33-item Childhood Trauma Questionnaire (CTQ-33) is a recently developed tool expanded from the 28-item Childhood Trauma Questionnaire (CTQ-28) to assess childhood trauma events, which showed good test-retest reliability over 2 weeks. However, little is known regarding the factor structure and long-term test-retest reliability of the CTQ-33. To fill such a gap, this study investigated the factorial validity of the CTQ-33 and test-retest reliability of the scale over a relatively long interval of 1 year. Data on demographics, the CTQ-33 scores, and mental health statuses such as depressive/anxiety symptoms were collected in Chinese adolescents (n = 188) twice across a one-year period. Results of the confirmatory factor analysis (CFA) revealed that the Chinese version of CTQ-33 has close factor validity when compared to the original CTQ-28 in college students. Furthermore, the total and most subscale scores of the CTQ-33 have fair to good test-retest reliability (intra-class correlation coefficients >0.6 for the total score, and > 0.4 for most subscales), except for the physical abuse subscale. Moreover, we replicated previous findings of significant positive relationships between levels of different childhood trauma subtypes using the CTQ-33. These findings provide initial evidence supporting that the CTQ-33 is overall reliable to assess childhood traumatic events in adolescents over relatively long intervals.
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- 2024
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11. Effect of body mass index and cholesterol‐rich apolipoprotein‐B‐containing lipoproteins on clinical outcome in NSCLC patients treated with immune checkpoint inhibitors‐based therapy: A retrospective analysis
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Zixin Hu, Yumin Zheng, Jiabin Zheng, Yan Wang, Jiangquan Liao, Zhening Liu, Jia Li, and Huijuan Cui
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body mass index ,immune checkpoint inhibitor ,low‐density lipoprotein cholesterol ,non‐small cell lung cancer ,remnant cholesterol ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Objectives Obesity and hypercholesterolemia are linked to unfavor clinical outcomes. Recent studies declared the paradox that high body mass index (BMI) and serum cholesterol were independently connected to better clinical outcome of immune checkpoint inhibitors (ICIs) monotherapy in non‐small cell lung cancer (NSCLC). The aim of the study is to investigate the prognosis of BMI and serum cholesterol in ICIs‐based therapy. Methods This is a retrospective study of 95 NSCLC patients treated with ICIs‐based therapy at the Department of Oncology and Lung Cancer Center of China‐Japan Friendship Hospital. Treatment efficacy was assessed using durable clinical benefit (DCB) versus nondurable benefit (NDB), best response (active vs. nonactive), and progression‐free survival (PFS). The prognostic value of BMI, LDL‐C, and RC was determined by multivariate regression analyses, while controlling for confounding factors including age, gender, diabetes status, smoking history, and statin usage. BMI was considered a confounding factor in the analysis when examining the impact of lipoproteins. Results In our study, we found that in the whole group, BMI ≥25 kg/m2 was linked to a higher risk of poor therapeutic response (OR = 5.92, 95% CI 1.99–19.51, p.val = 0.002) and shorter progression‐free survival (HR = 3.00, 95% CI 1.59–5.68, p.val = 0.001). In addition, low levels of RC were associated with better therapeutic response (OR = 0.12, 95% CI 0.02–0.64, p.val = 0.019), while low levels of serum LDL‐C were found to predict longer PFS (HR = 0.40, 95% CI 0.19–0.82, p.val = 0.012). These associations were consistent in advanced NSCLC patients receiving ICIs and chemotherapy. Conclusions Our study suggest that BMI ≥25 kg/m2 and elevated levels of apoB‐containing lipoproteins, including LDL‐C and RC, could potentially serve as useful prognostic markers for predicting poor treatment outcomes in advanced NSCLC patients treated with the combination of chemotherapy and ICIs.
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- 2024
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12. Different dietary carbohydrate component intakes and long-term outcomes in patients with NAFLD: results of longitudinal analysis from the UK Biobank
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Zhening Liu, Hangkai Huang, Jiarong Xie, Linxiao Hou, and Chengfu Xu
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Non-alcoholic fatty liver disease ,Carbohydrate quality ,End-stage liver disease ,Mortality ,Substitution ,Nutrition. Foods and food supply ,TX341-641 ,Nutritional diseases. Deficiency diseases ,RC620-627 - Abstract
Abstract Background This study aimed to investigate the association between the intake of different dietary carbohydrate components and the long-term outcomes of non-alcoholic fatty liver disease (NAFLD). Methods We used prospective data from 26,729 NAFLD participants from the UK Biobank cohort study. Dietary information was recorded by online 24-hour questionnaires (Oxford WebQ). Consumption of different carbohydrate components was calculated by the UK Nutrient Databank Food Composition Table. Cox proportional hazards models were used to estimate the adjusted hazard ratio (HR) and 95% confidence interval (CI). A substitution model was used to estimate the associations of hypothetical substitution for free sugars. Results During a median of 10.5 (IQR: 10.2–11.2) years and a total of 280,135 person-years of follow-up, 310 incident end-stage liver disease (ESLD) and 1750 deaths were recorded. Compared with the lowest quartile, the multi-adjusted HRs (95% CI) of incident ESLD in the highest quartile were 1.65 (1.14–2.39) for free sugars, 0.51 (0.35–0.74) for non-free sugars, and 0.55 (0.36–0.83) for fiber. For overall mortality, the multi-adjusted HRs (95% CI) in the highest quartile were 1.21 (1.04–1.39) for free sugars, 0.79 (0.68–0.92) for non-free sugars, and 0.79 (0.67–0.94) for fiber. Substituting free sugars with equal amounts of non-free sugars, starch or fiber was associated with a lower risk of incident ESLD and overall mortality. Conclusions A lower intake of free sugars and a higher intake of fiber are associated with a lower incidence of ESLD and overall mortality in NAFLD patients. These findings support the important role of the quality of dietary carbohydrates in preventing ESLD and overall mortality in NAFLD patients.
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- 2023
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13. On the tensor spectral p-norm and its dual norm via partitions
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Zhening Li and Bilian Chen
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Pure mathematics ,tensor partition ,Control and Optimization ,tensor norm bound ,Matrix norm ,010103 numerical & computational mathematics ,0102 computer and information sciences ,01 natural sciences ,Partition (number theory) ,Tensor ,0101 mathematics ,Dual norm ,Mathematics ,Conjecture ,Applied Mathematics ,Computing ,Matrix anal ,block tensor ,Computational Mathematics ,010201 computation theory & mathematics ,Bounded function ,spectral norm ,nuclear norm - Abstract
This paper presents a generalization of the spectral norm and the nuclear norm of a tensor via arbitrary tensor partitions, a much richer concept than block tensors. We show that the spectral p-norm and the nuclear p-norm of a tensor can be lower and upper bounded by manipulating the spectral p-norms and the nuclear p-norms of subtensors in an arbitrary partition of the tensor for $$1\le p\le \infty$$1≤p≤∞. Hence, it generalizes and answers affirmatively the conjecture proposed by Li (SIAM J Matrix Anal Appl 37:1440–1452, 2016) for a tensor partition and $$p=2$$p=2. We study the relations of the norms of a tensor, the norms of matrix unfoldings of the tensor, and the bounds via the norms of matrix slices of the tensor. Various bounds of the tensor spectral and nuclear norms in the literature are implied by our results.
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- 2020
14. On norm compression inequalities for partitioned block tensors
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Yun-Bin Zhao and Zhening Li
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Computer Science::Machine Learning ,tensor partition ,Pure mathematics ,0211 other engineering and technologies ,Matrix norm ,010103 numerical & computational mathematics ,02 engineering and technology ,Computer Science::Digital Libraries ,01 natural sciences ,Upper and lower bounds ,Statistics::Machine Learning ,norm compression inequality ,rank-one approximation ,Tensor ,0101 mathematics ,Mathematics ,021103 operations research ,Algebra and Number Theory ,Numerical analysis ,Computing ,block tensor ,Computational Mathematics ,Third order ,spectral norm ,Theory of computation ,Computer Science::Mathematical Software ,Norm (social) - Abstract
When a tensor is partitioned into subtensors, some tensor norms of these subtensors form a tensor called a norm compression tensor. Norm compression inequalities for tensors focus on the relation of the norm of this compressed tensor to the norm of the original tensor. We prove that for the tensor spectral norm, the norm of the compressed tensor is an upper bound of the norm of the original tensor. This result can be extended to a general class of tensor spectral norms. We discuss various applications of norm compression inequalities for tensors. These inequalities improve many existing bounds of tensor norms in the literature, in particular tightening the general bound of the tensor spectral norm via tensor partitions. We study the extremal ratio between the spectral norm and the Frobenius norm of a tensor space, provide a general way to estimate its upper bound, and in particular, improve the current best upper bound for third order nonnegative tensors and symmetric tensors. We also propose a faster approach to estimate the spectral norm of a large tensor or matrix via sequential norm compression inequalities with theoretical and numerical evidence. For instance, the complexity of our algorithm for the matrix spectral norm is$$O\left( n^{2+\epsilon }\right) $$On2+ϵwhere$$\epsilon $$ϵranges from 0 to 1 depending on the partition and the estimate ranges correspondingly from some close upper bound to the exact spectral norm.
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- 2020
15. On Orthogonal Tensors and Best Rank-One Approximation Ratio
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Tasuku Soma, Zhening Li, Yuji Nakatsukasa, and André Uschmajew
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Hurwitz problem ,Scalar (mathematics) ,Matrix norm ,010103 numerical & computational mathematics ,orthogonal tensor ,01 natural sciences ,Combinatorics ,Mathematics - Algebraic Geometry ,rank-one approximation ,FOS: Mathematics ,Mathematics - Numerical Analysis ,ddc:510 ,0101 mathematics ,Mathematics - Optimization and Control ,Algebraic Geometry (math.AG) ,Scaling ,Mathematics ,010102 general mathematics ,Computer Science - Numerical Analysis ,Numerical Analysis (math.NA) ,Optimization and Control (math.OC) ,spectral norm ,nuclear norm ,Analysis - Abstract
As is well known, the smallest possible ratio between the spectral norm and the Frobenius norm of an m × n matrix with m ≤ n is 1/√m and is (up to scalar scaling) attained only by matrices having pairwise orthonormal rows. In the present paper, the smallest possible ratio between spectral and Frobenius norms of n1 × ··· × nd tensors of order d, also called the best rank-one approximation ratio in the literature, is investigated. The exact value is not known for most configurations of n1 ≤ ··· ≤ nd. Using a natural definition of orthogonal tensors over the real field (resp., unitary tensors over the complex field), it is shown that the obvious lower bound 1/√n1···nd−1 is attained if and only if a tensor is orthogonal (resp., unitary) up to scaling. Whether or not orthogonal or unitary tensors exist depends on the dimensions n1, ..., nd and the field. A connection between the (non)existence of real orthogonal tensors of order three and the classical Hurwitz problem on composition algebras can be established: existence of orthogonal tensors of size l × m × n is equivalent to the admissibility of the triple [l, m, n] to the Hurwitz problem. Some implications for higher-order tensors are then given. For instance, real orthogonal n × ··· × n tensors of order d ≥ 3 do exist, but only when n = 1, 2, 4, 8. In the complex case, the situation is more drastic: unitary tensors of size l × m × n with l ≤ m ≤ n exist only when l m ≤ n. Finally, some numerical illustrations for spectral norm computation are presented.
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- 2018
16. Effects of long-term antipsychotic medication on brain instability in first-episode schizophrenia patients: a resting-state fMRI study
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Maoxing Zhong, Zhening Liu, Feiwen Wang, Jun Yang, Eric Chen, Edwin Lee, Guowei Wu, and Jie Yang
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antipsychotic drugs ,negative symptoms ,caudate ,supramarginal gyrus ,parahippocampal gyrus ,insula ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Early initiation of antipsychotic treatment plays a crucial role in the management of first-episode schizophrenia (FES) patients, significantly improving their prognosis. However, limited attention has been given to the long-term effects of antipsychotic drug therapy on FES patients. In this research, we examined the changes in abnormal brain regions among FES patients undergoing long-term treatment using a dynamic perspective. A total of 98 participants were included in the data analysis, comprising 48 FES patients, 50 healthy controls, 22 patients completed a follow-up period of more than 6 months with qualified data. We processed resting-state fMRI data to calculate coefficient of variation of fractional amplitude of low-frequency fluctuations (CVfALFF), which reflects the brain regional activity stability. Data analysis was performed at baseline and after long-term treatment. We observed that compared with HCs, patients at baseline showed an elevated CVfALFF in the supramarginal gyrus (SMG), parahippocampal gyrus (PHG), caudate, orbital part of inferior frontal gyrus (IOG), insula, and inferior frontal gyrus (IFG). After long-term treatment, the instability in SMG, PHG, caudate, IOG, insula and inferior IFG have ameliorated. Additionally, there was a positive correlation between the decrease in dfALFF in the SMG and the reduction in the SANS total score following long-term treatment. In conclusion, FES patients exhibit unstable regional activity in widespread brain regions at baseline, which can be ameliorated with long-term treatment. Moreover, the extent of amelioration in SMG instability is associated with the amelioration of negative symptoms.
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- 2024
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17. Influence of TMX2-CTNND1 polymorphism on cortical thickness in schizophrenia patients and unaffected siblings: an exploratory study based on target region sequencing
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Wenjian Tan, Yixin Cheng, Danqing Huang, Dayi Liu, Jiamei Zhang, Jinyue Li, Zhening Liu, and Yunzhi Pan
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Schizophrenia ,cortical thickness ,genetics ,Psychiatry ,RC435-571 - Abstract
Objective: The advancement of neuroimaging and genetic research has revealed the presence of morphological abnormalities and numerous risk genes, along with their associations. We aimed to estimate magnetic resonance imaging-derived cortical thickness across multiple brain regions. Methods: The cortical thickness of 129 schizophrenia patients, 42 of their unaffected siblings, and 112 healthy controls was measured and the candidate genes were sequenced. Comparisons were made of cortical thickness (including 68 regions of the Desikan-Killiany Atlas) and genetic variants (in 108 risk genes for schizophrenia) among the three groups, and correlation analyses were performed regarding cortical thickness, clinical symptoms, cognitive tests (such as the N-back task and the logical memory test), and genetic variants. Results: Schizophrenia patients had significantly thinner bilateral frontal, temporal, and parietal gyri than healthy controls and unaffected siblings. Association analyses in target genes showed that four single nucleotide variants (SNVs) were significantly associated with schizophrenia, including thioredoxin-related transmembrane protein 2-catenin, cadherin-associated protein, delta 1 (SNV20673) (positive false discovery rate [PFDR] = 0.008) and centromere protein M (rs35542507, rs41277477, rs73165153) (PFDR = 0.030). Additionally, cortical thickness in the right pars triangularis was lower in carriers of the SNV20673 variant than in non-carriers (PFDR = 0.048). Finally, a positive correlation was found between right pars triangularis cortical thickness and logical memory in schizophrenia patients (r = 0.199, p = 0.032). Conclusions: This study identified regional morphological abnormalities in schizophrenia, including the right homologue of Broca’s area, which was associated with a risk variant that affected delta-1 catenin and logical memory. These findings suggest a potential association between candidate gene loci, cortical thickness, and schizophrenia.
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- 2024
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18. Improvement of social functioning in patients with first-episode schizophrenia using blonanserin treatment: a prospective, multi-centre, single-arm clinical trial
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Tianqi Gao, Hong Deng, Jianhua Sheng, Bin Wu, Zhening Liu, Fude Yang, Lina Wang, Shaohua Hu, Xijin Wang, Haiyun Li, Chengcheng Pu, and Xin Yu
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blonanserin ,first-episode schizophrenia ,social functioning ,symtomatic and neurocognitive improvement ,clinical trial ,Psychiatry ,RC435-571 - Abstract
ObjectivesThis clinical trial primarily aimed to investigate the effects of blonanserin on social functioning in patients with first-episode schizophrenia.MethodsIn this prospective, multi-centre, single-arm clinical trial study, blonanserin (flexible oral dose ranging from 8mg to 24mg per day) was given 26 weeks. Outcome measures included the Personal and Social Performance (PSP) scale for evaluating social functioning, the Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Battery (MCCB) for measuring neurocognitive performance, and the Positive and Negative Syndrome Scale (PANSS) for assessing symptom severity. The primary endpoint was social function improvement evaluated by PSP scale at the end of blonanserin treatment. And the secondary endpoint was to validate the efficacy and neurocognitive effects of blonanserin. Adverse drug reactions (ADRs) were also recorded and analysed.ResultsA total of 96 patients with first-episode schizophrenia were recruited and proceeded to analysis. Fifty-one participants (53.1%) completed the PSP scale measurements at baseline and week 26. Following 26 weeks of blonanserin treatment, all outcome measurements demonstrated significant improvement during the follow-up period. Notably, PSP scores exhibited a continuous increase up to 68.1% ± 103.7% at the end of the treatment (46.6 ± 14.6 at baseline, 69.4 ± 17.4 at week 26, p
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- 2024
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19. Evolutionary auto-design for aircraft engine cycle
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Xudong Feng, Zhening Liu, Feng Wu, and Handing Wang
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Multi-objective evolutionary algorithms ,Engineering design ,Mixed variable encoding ,Electronic computers. Computer science ,QA75.5-76.95 ,Information technology ,T58.5-58.64 - Abstract
Abstract Traditional engine cycle innovation is limited by human experiences, imagination, and currently available engine component performance expectations. Thus, the engine cycle innovation process is quite slow for the past 90 years. In this work, we propose a mixed variable multi-objective evolutionary optimization method for automatic engine cycle design. In the first, a simulation toolkit is developed for performance evaluation of potentially viable engine cycle solutions. Then, the engine cycle solutions are mixed encoded by the pins and the parameters of different engine components. The new engine cycle solutions are generated through the mutation operator. Finally, we construct two optimization objectives to drive the optimization process. Through the experimental research, new engine cycle solutions are discovered that exceed the performance of known turbojet and turbofan engines.
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- 2023
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20. Association between night shift work and NAFLD: a prospective analysis of 281,280 UK Biobank participants
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Hangkai Huang, Zhening Liu, Jiarong Xie, and Chengfu Xu
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Night shift ,Nonalcoholic fatty liver disease ,Genetic risk ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Context This study aimed to investigate the association between night shift work and the risk of nonalcoholic fatty liver disease (NAFLD). Methods We conducted a prospective analysis of 281,280 UK Biobank participants. Cox proportional hazards models were used to estimate the association of night shift work with incident NAFLD. Polygenic risk score analyses were performed to assess whether a genetic predisposition to NAFLD modified the association. Results During a median follow-up of 12.1 years (3,373,964 person-years), 2,555 incident NAFLD cases were identified. Compared with workers who never/rarely worked night shifts, those who worked some night shifts or usual/permanent night shifts were 1.12 (95% CI: 0.96–1.31) and 1.27 (95% CI: 1.08–1.48) times more likely to develop NAFLD, respectively. Among the 75,059 participants who had reports on lifetime experience of night shift work, those with a longer duration, a higher frequency, more consecutive night shifts and a longer length per shift all showed higher risks of incident NAFLD. Further analyses showed that the association between night shift work and incident NAFLD was not modified by a genetic predisposition to NAFLD. Conclusions Night shift work was associated with increased risks of incident NAFLD.
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- 2023
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21. Approximation algorithms for optimization of real-valued general conjugate complex forms
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Zhening Li, Bo Jiang, and Taoran Fu
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Control and Optimization ,tensor relaxation ,0211 other engineering and technologies ,010103 numerical & computational mathematics ,02 engineering and technology ,Management Science and Operations Research ,01 natural sciences ,complex tensor ,Reciprocal polynomial ,complex polynomial optimization ,Imaginary unit ,Hermitian function ,90C59, 90C26, 90C10, 15A69, 60E15 ,FOS: Mathematics ,Applied mathematics ,Linear complex structure ,0101 mathematics ,Mathematics - Optimization and Control ,approximation algorithm ,Mathematics ,Discrete mathematics ,021103 operations research ,Complex conjugate ,Zero of a function ,Applied Mathematics ,probability bound ,random sampling ,Computing ,Hermitian matrix ,Computer Science Applications ,Optimization and Control (math.OC) ,general conjugate form ,Complex conjugate root theorem - Abstract
Complex polynomial optimization has recently gained more attention in both theory and practice. In this paper, we study optimization of a real-valued general conjugate complex form over various popular constraint sets including the m-th roots of complex unity, the complex unit circle, and the complex unit sphere. A real-valued general conjugate complex form is a homogenous polynomial function of complex variables as well as their conjugates, and always takes real values. General conjugate form optimization is a wide class of complex polynomial optimization models, which include many homogenous polynomial optimization in the real domain with either discrete or continuous variables, and Hermitian quadratic form optimization as well as its higher degree extensions. All the problems under consideration are NP-hard in general and we focus on polynomial-time approximation algorithms with worst-case performance ratios. These approximation ratios improve previous results when restricting our problems to some special classes of complex polynomial optimization, and improve or equate previous results when restricting our problems to some special classes of polynomial optimization in the real domain. The algorithms are based on tensor relaxation and random sampling. Our novel technical contributions are to establish the first set of probability lower bounds for random sampling over the m-th root of unity, the complex unit circle, and the complex unit sphere, and to propose the first polarization formula linking general conjugate forms and complex multilinear forms. Some preliminary numerical experiments are conducted to show good performance of the proposed algorithms.
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- 2018
22. On Cones of Nonnegative Quartic Forms
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Zhening Li, Bo Jiang, and Shuzhong Zhang
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Pure mathematics ,Polynomial ,Quartic plane curve ,0211 other engineering and technologies ,cone of polynomial functions ,010103 numerical & computational mathematics ,02 engineering and technology ,01 natural sciences ,Symmetric polynomial ,Quartic function ,polynomial optimization ,0101 mathematics ,Quartic surface ,nonnegative quartic forms ,Mathematics ,021103 operations research ,Power sum symmetric polynomial ,Applied Mathematics ,Computing ,SOS-convexity ,Quintic function ,sums of squares ,Algebra ,Computational Mathematics ,super-symmetric tensors ,Computational Theory and Mathematics ,Elementary symmetric polynomial ,Analysis - Abstract
Historically, much of the theory and practice in nonlinear optimization has revolved around the quadratic models. Though quadratic functions are nonlinear polynomials, they are well structured and easy to deal with. Limitations of the quadratics, however, become increasingly binding as higher degree nonlinearity is imperative in modern applications of optimization. In the recent years, one observes a surge of research activities in polynomial optimization, and modeling with quartic or higher order polynomial functions has been more commonly accepted. On the theoretical side, there are also major recent progresses on polynomial functions and optimization. For instance, Ahmadi et al. [2] proved that checking the convexity of a quartic polynomial function is strongly NP-hard in general, which settles a long-standing open question. In this paper we proceed to studying six fundamentally important convex cones of quartic functions in the space of symmetric quartic tensors, including the cone of nonnegative quartic polynomials, the sum of squared polynomials, the convex quartic polynomials, and the sum of fourth powered polynomials. It turns out that these convex cones coagulate into a chain in decreasing order. The complexity status of these cones is sorted out as well. Finally, potential applications of the new results to solve highly nonlinear and/or combinatorial optimization problems are discussed.
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- 2015
23. Profile and mental health characterization of childhood overprotection/overcontrol experiences among Chinese university students: a nationwide survey
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Jiamei Zhang, Zhipeng Wu, Haojuan Tao, Min Chen, Miaoyu Yu, Liang Zhou, Meng Sun, Dongsheng Lv, Guangcheng Cui, Qizhong Yi, Hong Tang, Cuixia An, Zhening Liu, Xiaojun Huang, and Yicheng Long
- Subjects
childhood trauma ,overprotection ,overcontrol ,mental health ,depression ,psychotic-like experience ,Psychiatry ,RC435-571 - Abstract
IntroductionThe childhood experiences of being overprotected and overcontrolled by family members have been suggested to be potentially traumatic. However, the possible associated factors of these experiences among young people are still not well studied. This study aimed to partly fill such gaps by a relatively large, nationwide survey of Chinese university students.MethodsA total of 5,823 university students across nine different provinces in China were included by the convenience sampling method in the data analyses. All participants completed the overprotection/overcontrol (OP/OC) subscale in a recently developed 33-item childhood trauma questionnaire (CTQ- 33). Data were also collected on all participants’ socio-demographic profiles and characterization of mental health. Binary logistic regression was conducted to investigate the associated socio-demographic and psychological factors of OP/ OC.ResultsThe prevalence of childhood OP/OC was estimated as 15.63% (910/5,823) based on a cutoff OP/OC subscale score of ≥ 13. Binary logistic regression suggested that being male, being a single child, having depression, having psychotic-like experiences, lower family functioning, and lower psychological resilience were independently associated with childhood OP/OC experiences (all corrected-p
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- 2023
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24. On new classes of nonnegative symmetric tensors
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Simai He, Shuzhong Zhang, Bilian Chen, and Zhening Li
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Pure mathematics ,0211 other engineering and technologies ,02 engineering and technology ,01 natural sciences ,Theoretical Computer Science ,nonnegative forms ,Symmetric polynomial ,Quartic function ,symmetric tensors ,Tensor ,0101 mathematics ,Mathematics ,polynomial and tensor optimization ,021103 operations research ,Power sum symmetric polynomial ,010102 general mathematics ,Mathematical analysis ,Computing ,Complete homogeneous symmetric polynomial ,Homogeneous polynomial ,Invariants of tensors ,Elementary symmetric polynomial ,Software - Abstract
In this paper we introduce three new classes of nonnegative forms (or equivalently, symmetric tensors) and their extensions. The newly identified nonnegative symmetric tensors constitute distinctive convex cones in the space of general symmetric tensors (order six or above). For the special case of quartic forms, they collapse into the set of convex quartic homogeneous polynomial functions. We discuss the properties and applications of the new classes of nonnegative symmetric tensors in the context of polynomial and tensor optimization. Numerical experiments for solving certain polynomial optimization models based on the new classes of nonnegative symmetric tensors are presented.
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- 2017
25. Association between serum uric acid levels and long-term mortality of metabolic dysfunction-associated fatty liver disease: a nationwide cohort study
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Zhening Liu, Qinqiu Wang, Hangkai Huang, Xinyu Wang, and Chengfu Xu
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Uric acid ,Fatty liver disease ,Metabolic disorders ,Mortality ,Non-linearity ,Nutritional diseases. Deficiency diseases ,RC620-627 - Abstract
Abstract Background The association between hyperuricemia and metabolic dysfunction-associated fatty liver disease (MAFLD) remains undetermined. This study aimed to examine the association of serum uric acid (SUA) levels with prevalence and long-term mortality of MAFLD in a nationally representative sample of US adults. Methods This analysis included 11,177 participants from the Third National Health and Nutrition Examination Survey (NHANES III, 1988–1994) with matched mortality data until 2019. We used logistic regression models to estimate the adjusted odd ratios (ORs) for factors associated with risk of MAFLD, and applied restricted cubic spline (RCS) regression to assess the non-linear associations of SUA levels with all-cause and cause-specific mortality of MAFLD. We also used Cox proportional hazards regression analysis to estimate hazard ratios (HRs) for the mortality. Results A higher SUA level contributed to a significant increased risk of MAFLD. every 1 mg/dL increment of SUA level was related to 17% (95% CI 9–24%) increased risk of MAFLD. Furthermore, a U-shaped association for males and a J-shaped association for females was discovered between SUA levels and all-cause mortality in participants with MAFLD. Specifically, among males, when SUA > 6.7 mg/dL, the higher SUA showed increased risk of cardio-cerebrovascular disease (CVD) mortality [HR (95% CI): 1.29 (1.05–1.58)]. As for females, only when SUA > 5.5 mg/dL, it showed a significantly positive association with risk of CVD and cancer mortality [HR (95% CI) 1.62 (1.24–2.13) and 1.95 (1.41–2.68)]. Conclusions Elevated SUA level is significantly associated with an increased risk of MAFLD. Besides, SUA level is also a predictor of long-term mortality of MAFLD.
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- 2023
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26. Profiles of depressive symptoms and influential factors among people living with HIV in China
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Dongfang Wang, Qijian Deng, Huilin Chen, Min Wang, Zhening Liu, Honghong Wang, and Xuan Ouyang
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Depressive symptoms ,People living with HIV ,Family function ,Resilience ,Childhood trauma ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Depressive symptoms are highly prevalent among people living with HIV (PLWH). We leveraged Latent Profile Analysis (LPA) to identify profiles of depressive symptoms among PLWHs. We also investigated differences in psychological factors of interest, demographic characteristics, and HIV-related factors across patients’ profiles. Methods A cross-sectional study was conducted at one hospital and two designated prison facilities in Hunan province, China. A total sample of 533 PLWHs (320 recruited from the hospital, 213 recruited from prisons) completed the survey. Depressive symptoms were assessed using the 9-item Patient Health Questionnaire (PHQ-9). Family function, resilience, childhood trauma, demographic characteristics, and HIV-related factors were also evaluated. We conducted LPA and multinomial logistic regression analyses to: 1) identify distinct profiles for depressive symptoms; 2) identify demographic characteristics, and HIV-related, and psychological factors predicting PLWHs’ likelihood to express a specific profile. Results We identified three distinct profiles of depressive symptoms among PLWHs: severe symptoms (11.8%), moderate symptoms (40.5%), and low/no symptoms (47.7%). Moderate/ severe family dysfunction, low resilience, experiencing emotional abuse and neglect were more likely to fall in the “severe symptoms” rather than the “low/no symptoms” profile. In addition, severe family dysfunction, low resilience, and experiencing emotional neglect indicated a higher likelihood of being classified in the “moderate symptoms” profile, compared to the “low/no symptoms” profile. Conclusion Identifying profiles of depressive symptoms among PLWHs using the PHQ-9 items allows for understanding of the distinct paths of development of depressive symptoms and for developing tailored prevention and intervention programs for PLWHs.
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- 2023
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27. Moments Tensors, Hilbert's Identity, and k-wise Uncorrelated Random Variables
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Bo Jiang, Zhening Li, Shuzhong Zhang, and Simai He
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Discrete mathematics ,Exchangeable random variables ,Pairwise independence ,Multivariate random variable ,General Mathematics ,uncorrelated random variables ,Statistics ,Computing ,Positive-definite matrix ,Management Science and Operations Research ,cone of moments ,matrix norm ,Computer Science Applications ,Combinatorics ,Hilbert's identity ,Convergence of random variables ,TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY ,Sum of normally distributed random variables ,Symmetrization ,Random variable ,Mathematics - Abstract
In this paper, we introduce a notion to be called k-wise uncorrelated random variables, which is similar but not identical to the so-called k-wise independent random variables in the literature. We show how to construct k-wise uncorrelated random variables by a simple procedure. The constructed random variables can be applied, e.g., to express the quartic polynomial (xTQx)2, where Q is an n × n positive semidefinite matrix, by a sum of fourth powered polynomial terms, known as Hilbert's identity. By virtue of the proposed construction, the number of required terms is no more than 2n4 + n. This implies that it is possible to find a (2n4 + n)-point distribution whose fourth moments tensor is exactly the symmetrization of Q ⊗ Q. Moreover, we prove that the number of required fourth powered polynomial terms to express (xTQx)2 is at least n(n + 1)/2. The result is applied to prove that computing the matrix 2 ↦ 4 norm is NP-hard. Extensions of the results to complex random variables are discussed as well.
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- 2014
28. Probability Bounds for Polynomial Functions in Random Variables
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Bo Jiang, Zhening Li, Shuzhong Zhang, and Simai He
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Multivariate random variable ,General Mathematics ,Management Science and Operations Research ,Combinatorics ,Minimal polynomial (field theory) ,polynomial optimization ,polynomial function ,approximation algorithm ,Mathematics ,Discrete mathematics ,Zero of a function ,probability bound ,random sampling ,Statistics ,Computing ,Random element ,Moment-generating function ,tensor form ,Computer Science Applications ,Randomized algorithm ,Homogeneous polynomial ,Random variable - Abstract
Random sampling is a simple but powerful method in statistics and in the design of randomized algorithms. In a typical application, random sampling can be applied to estimate an extreme value, say maximum, of a function f over a set S ⊆ ℝn. To do so, one may select a simpler (even finite) subset S0 ⊆ S, randomly take some samples over S0 for a number of times, and pick the best sample. The hope is to find a good approximate solution with reasonable chance. This paper sets out to present a number of scenarios for f, S and S0 where certain probability bounds can be established, leading to a quality assurance of the procedure. In our setting, f is a multivariate polynomial function. We prove that if f is a d-th order homogeneous polynomial in n variables and F is its corresponding super-symmetric tensor, and ξi (i = 1, 2, …, n) are i.i.d. Bernoulli random variables taking 1 or −1 with equal probability, then Prob{f(ξ1, ξ2, …, ξn) ≥ τn−d/2 ‖F‖1} ≥ θ, where τ, θ > 0 are two universal constants and ‖·‖1 denotes the summation of the absolute values of all its entries. Several new inequalities concerning probabilities of the above nature are presented in this paper. Moreover, we show that the bounds are tight in most cases. Applications of our results in optimization are discussed as well.
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- 2014
29. Approximation methods for complex polynomial optimization
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Zhening Li, Shuzhong Zhang, and Bo Jiang
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Discrete mathematics ,complex programming ,Polynomial ,tensor relaxation ,Control and Optimization ,Zero of a function ,Applied Mathematics ,Computing ,Polarization of an algebraic form ,complex tensor ,Matrix polynomial ,Properties of polynomial roots ,Computational Mathematics ,Reciprocal polynomial ,Symmetric polynomial ,polynomial optimization ,ComputingMethodologies_SYMBOLICANDALGEBRAICMANIPULATION ,Applied mathematics ,approximation algorithm ,Mathematics ,Monic polynomial - Abstract
Complex polynomial optimization problems arise from real-life applications including radar code design, MIMO beamforming, and quantum mechanics. In this paper, we study complex polynomial optimization models where the objective function takes one of the following three forms: (1) multilinear; (2) homogeneous polynomial; (3) symmetric conjugate form. On the constraint side, the decision variables belong to one of the following three sets: (1) the $$m$$ m -th roots of complex unity; (2) the complex unity; (3) the Euclidean sphere. We first discuss the multilinear objective function. Polynomial-time approximation algorithms are proposed for such problems with assured worst-case performance ratios, which depend only on the dimensions of the model. Then we introduce complex homogenous polynomial functions and establish key linkages between complex multilinear forms and the complex polynomial functions. Approximation algorithms for the above-mentioned complex polynomial optimization models with worst-case performance ratios are presented. Numerical results are reported to illustrate the effectiveness of the proposed approximation algorithms.
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- 2014
30. Bounds on the spectral norm and the nuclear norm of a tensor based on tensor partitions
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Zhening Li
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Pure mathematics ,tensor partition ,Nuclear Theory ,0211 other engineering and technologies ,Matrix norm ,Tensor product of Hilbert spaces ,tensor norm ,010103 numerical & computational mathematics ,02 engineering and technology ,01 natural sciences ,Symmetric tensor ,0101 mathematics ,Dual norm ,Mathematics ,Tensor contraction ,021103 operations research ,Mathematical analysis ,Computing ,approximation bound ,block tensor ,spectral norm ,Schatten norm ,nuclear norm ,Tensor density ,Operator norm ,Analysis - Abstract
It is known that computing the spectral norm and the nuclear norm of a tensor is NP-hard in general. In this paper, we provide neat bounds for the spectral norm and the nuclear norm of a tensor based on tensor partitions. The spectral norm (respectively, the nuclear norm) can be lower and upper bounded by manipulating the spectral norms (respectively, the nuclear norms) of its subtensors. The bounds are sharp in general. When a tensor is partitioned into its matrix slices, our inequalities provide polynomial-time worst-case approximation bounds for computing the spectral norm and the nuclear norm of the tensor.
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- 2016
31. Mediating role of impaired wisdom in the relation between childhood trauma and psychotic-like experiences in Chinese college students: a nationwide cross-sectional study
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Jiamei Zhang, Zhening Liu, Yicheng Long, Haojuan Tao, Xuan Ouyang, Guowei Wu, Min Chen, Miaoyu Yu, Liang Zhou, Meng Sun, Dongsheng Lv, Guangcheng Cui, Qizhong Yi, Hong Tang, Cuixia An, Jianjian Wang, and Zhipeng Wu
- Subjects
Childhood trauma ,Wisdom ,Mediating effect ,Psychotic-like experiences ,Psychiatry ,RC435-571 - Abstract
Abstract Background: The association between childhood trauma (CT) and psychotic-like experiences (PLEs) is well-established. Many previous studies have recognized wisdom as a protective factor for mental health, but its role in the relation between CT and PLEs remains unknown. We aimed to investigate the mediating effect of wisdom in the above association among Chinese college students. Methods: We conducted a nationwide survey covering 9 colleges across China and recruited a total of 5873 students using online questionnaires between September 14 and October 18, 2021. Convenience sampling was adopted. We employed the San Diego Wisdom Scale (SD-WISE), the Childhood Trauma Questionnaire (CTQ-28), and the 15-item Positive Subscale of the Community Assessment of Psychic Experiences (CAPE-15) to measure the wisdom, CT and PLEs, respectively. Descriptive, correlation, and mediation analysis were utilized. Results: The positive correlation between CT and PLEs was well-replicated among college students (Pearson’s r = 0.30, p
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- 2022
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32. Characterizing real-valued multivariate complex polynomials and their symmetric tensor representations
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Shuzhong Zhang, Zhening Li, and Bo Jiang
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0211 other engineering and technologies ,010103 numerical & computational mathematics ,02 engineering and technology ,01 natural sciences ,conjugate complex polynomial ,Symmetric polynomial ,FOS: Mathematics ,symmetric complex tensor ,Symmetric tensor ,0101 mathematics ,Newton's identities ,Ring of symmetric functions ,Mathematics - Optimization and Control ,Mathematics ,tensor eigenvector ,021103 operations research ,Power sum symmetric polynomial ,Computing ,Complete homogeneous symmetric polynomial ,Hermitian matrix ,Algebra ,Banach’s theorem ,Optimization and Control (math.OC) ,15A69, 15A18, 15B57, 15B48 ,Elementary symmetric polynomial ,tensor eigenvalue ,Analysis - Abstract
In this paper we study multivariate polynomial functions in complex variables and the corresponding associated symmetric tensor representations. The focus is on finding conditions under which such complex polynomials/tensors always take real values. We introduce the notion of symmetric conjugate forms and general conjugate forms, and present characteristic conditions for such complex polynomials to be real-valued. As applications of our results, we discuss the relation between nonnegative polynomials and sums of squares in the context of complex polynomials. Moreover, new notions of eigenvalues/eigenvectors for complex tensors are introduced, extending properties from the Hermitian matrices. Finally, we discuss an important property for symmetric tensors, which states that the largest absolute value of eigenvalue of a symmetric real tensor is equal to its largest singular value; the result is known as Banach's theorem. We show that a similar result holds in the complex case as well.
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- 2016
33. Association between folate and non-alcoholic fatty liver disease among US adults: a nationwide cross-sectional analysis
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Zhening Liu, Yan Zeng, Shuxia Shen, Yu Wen, Chengfu Xu, Jinjiao Li, and Yuanyuan Ji
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Medicine - Published
- 2023
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34. Associations between polygenic risk, negative symptoms, and functional connectome topology during a working memory task in early-onset schizophrenia
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Mengjie Deng, Zhening Liu, Wen Zhang, Zhipeng Wu, Hengyi Cao, Jie Yang, and Lena Palaniyappan
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Psychiatry ,RC435-571 - Abstract
Abstract Working memory (WM) deficit in schizophrenia is thought to arise from a widespread neural inefficiency. However, we do not know if this deficit results from the illness-related genetic risk and influence the symptom burden in various domains, especially in patients who have an early onset illness. We used graph theory to examine the topology of the functional connectome in 99 subjects (27 early-onset schizophrenia (EOS), 24 asymptomatic siblings, and 48 healthy subjects) during an n-back task, and calculated their polygenic risk score (PRS) for susceptibility to schizophrenia. Linear regression analysis was used to test associations of the PRS, clinical symptoms, altered connectomic properties, and WM accuracy in EOS. Indices of small-worldness and segregation were elevated in EOS during the WM task compared with the other two groups; these connectomic aberrations correlated with increased PRS and negative symptoms. In patients with higher polygenic risk, WM performance was lower only when both the connectomic aberrations and the burden of negative symptoms were higher. Negative symptoms had a stronger moderating role in this relationship. Our findings suggest that the aberrant connectomic topology is a feature of WM task performance in schizophrenia; this relates to higher polygenic risk score as well as higher burden of negative symptoms. The deleterious effects of polygenic risk on cognition are played out via its effects on the functional connectome, as well as negative symptoms.
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- 2022
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35. Association of the android to gynoid fat ratio with nonalcoholic fatty liver disease: a cross-sectional study
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Ling Yang, Hangkai Huang, Zhening Liu, Jiaqi Ruan, and Chengfu Xu
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nonalcoholic fatty liver disease ,dual-energy X-ray absorptiometry ,android fat ,gynoid fat ,risk ,Nutrition. Foods and food supply ,TX341-641 - Abstract
BackgroundNonalcoholic fatty liver disease (NAFLD) is becoming a severe global public health problem, and can developed into fibrotic nonalcoholic steatohepatitis (NASH), but its risk factors have not been fully identified. The objective of this study was to investigate the association between the android-to-gynoid fat ratio (A/G ratio) and the prevalence of NAFLD.MethodsThis cross-sectional study is based on the 2003–2006 and 2011–2018 cycles of the National Health and Nutrition Examination Survey and included 10,989 participants. Participants aged 20 and older without viral hepatitis or significant alcohol consumption were included. Dual-energy X-ray absorptiometry was used to assess body composition. NAFLD was diagnosed using the United States fatty liver index (US FLI). Multivariable logistic regression models were used to evaluate the association between the A/G ratio and NAFLD.ResultsThe prevalence of NAFLD was 32.15% among the study population. Android percent fat and the A/G ratio were significantly higher in patients with NAFLD than in those without NAFLD [41.68% (0.25) vs. 32.80% (0.27), p
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- 2023
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36. On optimal low rank Tucker approximation for tensors:the case for an adjustable core size
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Zhening Li, Shuzhong Zhang, and Bilian Chen
- Subjects
low-rank approximation ,Mathematical optimization ,Control and Optimization ,Rank (linear algebra) ,Computer science ,Applied Mathematics ,Statistics ,Computing ,multiway array ,Low-rank approximation ,Management Science and Operations Research ,Computer Science Applications ,Chemometrics ,Core (game theory) ,maximum block improvement ,Tucker decomposition ,Tensor ,Algorithm ,Mathematics ,Block (data storage) ,Image compression - Abstract
Approximating high order tensors by low Tucker-rank tensors have applications in psychometrics, chemometrics, computer vision, biomedical informatics, among others. Traditionally, solution methods for finding a low Tucker-rank approximation presume that the size of the core tensor is specified in advance, which may not be a realistic assumption in many applications. In this paper we propose a new computational model where the configuration and the size of the core become a part of the decisions to be optimized. Our approach is based on the so-called maximum block improvement method for non-convex block optimization. Numerical tests on various real data sets from gene expression analysis and image compression are reported, which show promising performances of the proposed algorithms.
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- 2015
37. Inhomogeneous polynomial optimization over a convex set:an approximation approach
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Simai He, Zhening Li, and Shuzhong Zhang
- Subjects
Mathematical optimization ,Polynomial ,Algebra and Number Theory ,Applied Mathematics ,Convex set ,Linear matrix inequality ,Computing ,Approximation algorithm ,Subderivative ,tensor optimization ,Matrix polynomial ,Computational Mathematics ,TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY ,Convex optimization ,polynomial optimization ,inhomogeneous polynomial ,Monic polynomial ,approximation algorithm ,Mathematics - Abstract
In this paper, we consider computational methods for optimizing a multivariate inhomogeneous polynomial function over a general convex set. The focus is on the design and analysis of polynomial-time approximation algorithms. The methods are able to deal with optimization models with polynomial objective functions in any fixed degrees. In particular, we first study the problem of maximizing an inhomogeneous polynomial over the Euclidean ball. A polynomial-time approximation algorithm is proposed for this problem with an assured (relative) worst-case performance ratio, which is dependent only on the dimensions of the model. The method and approximation ratio are then generalized to optimize an inhomogeneous polynomial over the intersection of a finite number of co-centered ellipsoids. Furthermore, the constraint set is extended to a general convex compact set. Specifically, we propose a polynomial-time approximation algorithm with a (relative) worst-case performance ratio for polynomial optimization over some convex compact sets, e.g. a polytope. Finally, numerical results are reported, revealing good practical performance of the proposed algorithms for solving some randomly generated instances.
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- 2015
38. On convergence of the maximum block improvement method
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André Uschmajew, Shuzhong Zhang, and Zhening Li
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Mathematical optimization ,Optimization problem ,rank-one tensor approximation ,convergence ,nonconvex optimization ,Computing ,Theoretical Computer Science ,Matrix (mathematics) ,Local analysis ,Rate of convergence ,Power iteration ,maximum block improvement ,Convergence (routing) ,block coordinate descent ,Lojasiewicz inequality ,ddc:510 ,Finite set ,Software ,Mathematics ,Block (data storage) - Abstract
The MBI (maximum block improvement) method is a greedy approach to solving optimization problems where the decision variables can be grouped into a finite number of blocks. Assuming that optimizing over one block of variables while fixing all others is relatively easy, the MBI method updates the block of variables corresponding to the maximally improving block at each iteration, which is arguably a most natural and simple process to tackle block-structured problems with great potentials for engineering applications. In this paper we establish global and local linear convergence results for this method. The global convergence is established under the Lojasiewicz inequality assumption, while the local analysis invokes second-order assumptions. We study in particular the tensor optimization model with spherical constraints. Conditions for linear convergence of the famous power method for computing the maximum eigenvalue of a matrix follow in this framework as a special case. The condition is interpreted in various other forms for the rank-one tensor optimization model under spherical constraints. Numerical experiments are shown to support the convergence property of the MBI method.
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- 2015
39. Factors influencing medication adherence among patients with severe mental disorders from the perspective of mental health professionals
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Mengjie Deng, Shuyi Zhai, Xuan Ouyang, Zhening Liu, and Brendan Ross
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Medication adherence ,Severe mental disorders ,Qualitative research ,Psychiatry ,RC435-571 - Abstract
Abstract Background Medication adherence is a common issue influenced by various factors among patients with severe mental disorders worldwide. However, most literature to date has been primarily quantitative and has focused on medication adherence issue from the perspective of patients or their caregivers. Moreover, research focused on medication adherence issue in China is scarce. Present study aims to explore the influential factors of medication adherence among patients with severe mental disorders form the perspective of mental health professionals in Hunan Province, China. Methods A qualitative study was performed in Hunan Province, China with 31 mental health professionals recruited from October to November 2017. And semi-structured interviews or focus group interviews were conducted along with audio recordings of all interviews. Interview transcripts were then coded and analyzed in Nvivo software with standard qualitative approaches. Results Three major themes influencing medication adherence among patients with severe mental disorders were identified as: (1) attitudes towards mental disorder/treatment; (2) inadequate aftercare; (3) resource shortages. Conclusions This qualitative study identified the factors influencing medication adherence among patients with severe mental disorders in China. As a locally driven research study, it provides practical advice on medication adherence promotion for mental health workers and suggests culturally tailored models that improve the management of patients with severe mental disorders in order to reduce economic burden on individual and societal level.
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- 2022
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40. Mental health characteristics and their associations with childhood trauma among subgroups of people living with HIV in China
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Dongfang Wang, Qijian Deng, Brendan Ross, Min Wang, Zhening Liu, Honghong Wang, and Xuan Ouyang
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People living with HIV ,Psychotic-like experience ,Anxiety ,Depression ,Childhood trauma ,Psychiatry ,RC435-571 - Abstract
Abstract Background People living with HIV (PLWH) carry a high risk for mental health problems, which has been extensively reported in the literature. However, an understanding of mental health characteristics in different subgroups of PLWH is still limited. In the present study, we conducted a cross-sectional survey to explore mental health characteristics and their associations with childhood trauma in two major subgroups of PLWH in China. Methods A total of 533 PLWH (213 prisoners in the prison system, and 320 outpatients) were assessed using the 8-item Positive Subscale of the Community Assessment of Psychic Experiences (CAPE-P8), Generalized Anxiety Disorder scale (GAD-7), Patient Health Questionnaire (PHQ-9), and Childhood Trauma Questionnaire (CTQ). Results From the total sample, 22.0% PLWH frequently experienced psychotic-like experiences (PLEs), 21.8% had clinically significant anxiety syndrome, 34.0% had clinically significant depressive syndrome, and 63.6% experienced at least one type of traumatic exposure during their childhood, with physical neglect being the most common. Compared to outpatients with HIV, prisoners living with HIV reported more severe mental health problems and a higher frequency of childhood trauma, with childhood trauma in turn predicting higher risk for mental health problems. Similarly, among outpatients living with HIV, both childhood emotional and sexual abuse had predictive effects on all the three mental health problems. Conclusions The study suggests that PLWH have higher risk of anxiety, depression and PLEs, and childhood trauma could serve as predicting factors for such risks. In addition, childhood trauma may play distinct roles in predicting the risk for the mental health problems, depending on different subgroup of PLWH.
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- 2022
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41. Microsatellite instability-related prognostic risk score (MSI-pRS) defines a subset of lung squamous cell carcinoma (LUSC) patients with genomic instability and poor clinical outcome
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Zixin Hu, Zhening Liu, Jiabin Zheng, Yanmei Peng, Xingyu Lu, Jia Li, Kexin Tan, and Huijuan Cui
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lung squamous cell carcinoma ,genomic instability ,mismatch repair system ,microsatellite instability ,TP53 ,prognostic biomarkers ,Genetics ,QH426-470 - Abstract
Background: Lung squamous cell carcinoma (LUSC) shares less typical onco-drivers and target resistance, but a high overall mutation rate and marked genomic complexity. Mismatch repair (MMR) deficiency leads to microsatellite instability (MSI) and genomic instability. MSI is not an ideal option for prognosis of LUSC, whereas its function deserves exploration.Method: MSI status was classified by MMR proteins using unsupervised clustering in the TCGA–LUSC dataset. The MSI score of each sample was determined by gene set variation analysis. Intersections of the differential expression genes and differential methylation probes were classified into functional modules by weighted gene co-expression network analysis. Least absolute shrinkage and selection operator regression and stepwise gene selection were performed for model downscaling.Results: Compared with the MSI-low (MSI-L) phenotype, MSI-high (MSI-H) displayed higher genomic instability. The MSI score was decreased from MSI-H to normal samples (MSI-H > MSI-L > normal). A total of 843 genes activated by hypomethylation and 430 genes silenced by hypermethylation in MSI-H tumors were classified into six functional modules. CCDC68, LYSMD1, RPS7, and CDK20 were used to construct MSI-related prognostic risk score (MSI-pRS). Low MSI-pRS was a protective prognostic factor in all cohorts (HR = 0.46, 0.47, 0.37; p-value = 7.57e-06, 0.009, 0.021). The model contains tumor stage, age, and MSI-pRS that showed good discrimination and calibration. Decision curve analyses indicated that microsatellite instability-related prognostic risk score added extra value to the prognosis. A low MSI-pRS was negatively correlated with genomic instability. LUSC with low MSI-pRS was associated with increased genomic instability and cold immunophenotype.Conclusion: MSI-pRS is a promising prognostic biomarker in LUSC as the substitute of MSI. Moreover, we first declared that LYSMD1 contributed to genomic instability of LUSC. Our findings provided new insights in the biomarker finder of LUSC.
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- 2023
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42. Cortical morphological heterogeneity of schizophrenia and its relationship with glutamatergic receptor variations
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Xuan Ouyang, Yunzhi Pan, Xudong Chen, Guowei Wu, Yixin Cheng, Wenjian Tan, Manqi Zhang, Mengjie Deng, Zhening Liu, and Lena Palaniyappan
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Cortical folding ,polymorphisms ,prognosis ,stratification ,unsupervised machine learning ,Psychiatry ,RC435-571 - Abstract
Abstract Background Recent genetic evidence implicates glutamatergic-receptor variations in schizophrenia. Glutamatergic excess during early life in people with schizophrenia may cause excitotoxicity and produce structural deficits in the brain. Cortical thickness and gyrification are reduced in schizophrenia, but only a subgroup of patients exhibits such structural deficits. We delineate the structural variations among unaffected siblings and patients with schizophrenia and study the role of key glutamate-receptor polymorphisms on these variations. Methods Gaussian Mixture Model clustering was applied to the cortical thickness and gyrification data of 114 patients, 112 healthy controls, and 42 unaffected siblings to identify subgroups. The distribution of glutamate-receptor (GRM3, GRIN2A, and GRIA1) and voltage-gated calcium channel (CACNA1C) variations across the MRI-based subgroups was studied. The comparisons in clinical symptoms and cognition between patient subgroups were conducted. Results We observed a “hypogyric,” “impoverished-thickness,” and “supra-normal” subgroups of patients, with higher negative symptom burden and poorer verbal fluency in the hypogyric subgroup and notable functional deterioration in the impoverished-thickness subgroup. Compared to healthy subjects, the hypogyric subgroup had significant GRIN2A and GRM3 variations, the impoverished-thickness subgroup had CACNA1C variations while the supra-normal group had no differences. Conclusions Disrupted gyrification and thickness can be traced to the glutamatergic receptor and voltage-gated calcium channel dysfunction respectively in schizophrenia. This raises the question of whether MRI-based multimetric subtyping may be relevant for clinical trials of agents affecting the glutamatergic system.
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- 2023
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43. Approximation Methods for Polynomial Optimization : Models, Algorithms, and Applications
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Zhening Li, Simai He, Shuzhong Zhang, Zhening Li, Simai He, and Shuzhong Zhang
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- Approximation algorithms, Mathematical optimization
- Abstract
Polynomial optimization have been a hot research topic for the past few years and its applications range from Operations Research, biomedical engineering, investment science, to quantum mechanics, linear algebra, and signal processing, among many others. In this brief the authors discuss some important subclasses of polynomial optimization models arising from various applications, with a focus on approximations algorithms with guaranteed worst case performance analysis. The brief presents a clear view of the basic ideas underlying the design of such algorithms and the benefits are highlighted by illustrative examples showing the possible applications. This timely treatise will appeal to researchers and graduate students in the fields of optimization, computational mathematics, Operations Research, industrial engineering, and computer science.
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- 2012
44. Decreased integration of default-mode network during a working memory task in schizophrenia with severe attention deficits
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Peng Cheng, Zhening Liu, Jun Yang, Fuping Sun, Zebin Fan, and Jie Yang
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working memory ,attention deficits ,brain networks ,graph theory ,N-back task ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
BackgroundWorking memory (WM) and attention deficits are both important features of schizophrenia. WM is closely related to attention, for it acted as an important characteristic in activating and manipulating WM. However, the knowledge of neural mechanisms underlying the relationship between WM and attention deficits in schizophrenia is poorly investigated.MethodsGraph theory was used to examine the network topology at the whole-brain and large-scale network levels among 125 schizophrenia patients with different severity of attention deficits (65 mild attention deficits; 46 moderate attention deficits; and 14 severe attention deficits) and 53 healthy controls (HCs) during an N-back WM task. These analyses were repeated in the same participants during the resting state.ResultsIn the WM task, there were omnibus differences in small-worldness and normalized clustering coefficient at a whole-brain level and normalized characterized path length of the default-mode network (DMN) among all groups. Post hoc analysis further indicated that all patient groups showed increased small-worldness and normalized clustering coefficient of the whole brain compared with HCs, and schizophrenia with severe attention deficits showed increased normalized characterized path length of the DMN compared with schizophrenia with mild attention deficits and HCs. However, these observations were not persisted under the resting state. Further correlation analyses indicated that the increased normalized characterized path length of the DMN was correlated with more severe attentional deficits and poorer accuracy of the WM task.ConclusionOur research demonstrated that, compared with the schizophrenia patients with less attention deficits, disrupted integration of the DMN may more particularly underlie the WM deficits in schizophrenia patients with severe attention deficits.
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- 2022
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45. Problematic smartphone use is associated with differences in static and dynamic brain functional connectivity in young adults
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Dayi Liu, Xiaoxuan Liu, Yicheng Long, Zhibiao Xiang, Zhipeng Wu, Zhening Liu, Dujun Bian, and Shixiong Tang
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addiction ,problematic smartphone use ,mobile phone use ,fMRI ,dynamic functional connectivity ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
IntroductionThis study aimed to investigate the possible associations between problematic smartphone use and brain functions in terms of both static and dynamic functional connectivity patterns.Materials and methodsResting-state functional magnetic resonance imaging data were scanned from 53 young healthy adults, all of whom completed the Short Version of the Smartphone Addiction Scale (SAS-SV) to assess their problematic smartphone use severity. Both static and dynamic functional brain network measures were evaluated for each participant. The brain network measures were correlated the SAS-SV scores, and compared between participants with and without a problematic smartphone use after adjusting for sex, age, education, and head motion.ResultsTwo participants were excluded because of excessive head motion, and 56.9% (29/51) of the final analyzed participants were found to have a problematic smartphone use (SAS-SV scores ≥ 31 for males and ≥ 33 for females, as proposed in prior research). At the global network level, the SAS-SV score was found to be significantly positively correlated with the global efficiency and local efficiency of static brain networks, and negatively correlated with the temporal variability using the dynamic brain network model. Large-scale subnetwork analyses indicated that a higher SAS-SV score was significantly associated with higher strengths of static functional connectivity within the frontoparietal and cinguloopercular subnetworks, as well as a lower temporal variability of dynamic functional connectivity patterns within the attention subnetwork. However, no significant differences were found when directly comparing between the groups of participants with and without a problematic smartphone use.ConclusionOur results suggested that problematic smartphone use is associated with differences in both the static and dynamic brain network organizations in young adults. These findings may help to identify at-risk population for smartphone addiction and guide targeted interventions for further research. Nevertheless, it might be necessary to confirm our findings in a larger sample, and to investigate if a more applicable SAS-SV cutoff point is required for defining problematic smartphone use in young Chinese adults nowadays.
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- 2022
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46. Approximation algorithms for discrete polynomial optimization
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Shuzhong Zhang, Simai He, and Zhening Li
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Polynomial ,Mathematical optimization ,polynomial optimization problem ,Zero of a function ,binary integer programming ,Computing ,Approximation algorithm ,Binary constraint ,Management Science and Operations Research ,mixed integer programming ,Matrix polynomial ,Symmetric polynomial ,Homogeneous polynomial ,approximation ratio ,Monic polynomial ,approximation algorithm ,Mathematics - Abstract
In this paper, we consider approximation algorithms for optimizing a generic multivariate polynomial function in discrete (typically binary) variables. Such models have natural applications in graph theory, neural networks, error-correcting codes, among many others. In particular, we focus on three types of optimization models: (1) maximizing a homogeneous polynomial function in binary variables; (2) maximizing a homogeneous polynomial function in binary variables, mixed with variables under spherical constraints; (3) maximizing an inhomogeneous polynomial function in binary variables. We propose polynomial-time randomized approximation algorithms for such polynomial optimization models, and establish the approximation ratios (or relative approximation ratios whenever appropriate) for the proposed algorithms. Some examples of applications for these models and algorithms are discussed as well.
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- 2013
47. ON ORTHOGONAL TENSORS AND BEST RANK-ONE APPROXIMATION RATIO.
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ZHENING LI, YUJI NAKATSUKASA, TASUKU SOMA, and USCHMAJEW, ANDRÉ
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- *
ORTHOGONAL decompositions , *APPROXIMATION theory , *HURWITZ polynomials , *NUMERICAL analysis , *MATRIX norms , *PERTURBATION theory - Abstract
As is well known, the smallest possible ratio between the spectral norm and the Frobenius norm of an m x n matrix with m x n is 1= p m and is (up to scalar scaling) attained only by matrices having pairwise orthonormal rows. In the present paper, the smallest possible ratio between spectral and Frobenius norms of n1 find tensors of order d, also called the best rank-one approximation ratio in the literature, is investigated. The exact value is not known for most configurations of n1 nd. Using a natural definition of orthogonal tensors over the real field (resp., unitary tensors over the complex field), it is shown that the obvious lower bound 1= p n1 nd1 is attained if and only if a tensor is orthogonal (resp., unitary) up to scaling. Whether or not orthogonal or unitary tensors exist depends on the dimensions n1; : : : ; nd and the field. A connection between the (non)existence of real orthogonal tensors of order three and the classical Hurwitz problem on composition algebras can be established: existence of orthogonal tensors of size ` x m x n is equivalent to the admissibility of the triple [`; m; n] to the Hurwitz problem. Some implications for higher-order tensors are then given. For instance, real orthogonal n n tensors of order d x 3 do exist, but only when n = 1; 2; 4; 8. In the complex case, the situation is more drastic: unitary tensors of size ` x m x n with ` x m x n exist only when `m x n. Finally, some numerical illustrations for spectral norm computation are presented. [ABSTRACT FROM AUTHOR]
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- 2018
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48. Hypoactive Visual Cortex, Prefrontal Cortex and Insula during Self-Face Recognition in Adults with First-Episode Major Depressive Disorder
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Zebin Fan, Zhening Liu, Jie Yang, Jun Yang, Fuping Sun, Shixiong Tang, Guowei Wu, Shuixia Guo, Xuan Ouyang, and Haojuan Tao
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major depressive disorder ,self-face recognition ,visual cortex ,task functional magnetic resonance imaging ,Biology (General) ,QH301-705.5 - Abstract
Self-face recognition is a vital aspect of self-referential processing, which is closely related to affective states. However, neuroimaging research on self-face recognition in adults with major depressive disorder is lacking. This study aims to investigate the alteration of brain activation during self-face recognition in adults with first-episode major depressive disorder (FEMDD) via functional magnetic resonance imaging (fMRI); FEMDD (n = 59) and healthy controls (HC, n = 36) who performed a self-face-recognition task during the fMRI scan. The differences in brain activation signal values between the two groups were analyzed, and Pearson correlation analysis was used to evaluate the relationship between the brain activation of significant group differences and the severity of depressive symptoms and negative self-evaluation; FEMDD showed significantly decreased brain activation in the bilateral occipital cortex, bilateral fusiform gyrus, right inferior frontal gyrus, and right insula during the task compared with HC. No significant correlation was detected between brain activation with significant group differences and the severity of depression and negative self-evaluation in FEMDD or HC. The results suggest the involvement of the malfunctioning visual cortex, prefrontal cortex, and insula in the pathophysiology of self-face recognition in FEMDD, which may provide a novel therapeutic target for adults with FEMDD.
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- 2023
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49. Attention-Guided Huber Loss for Head Pose Estimation Based on Improved Capsule Network
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Runhao Zhong, Li He, Hongwei Wang, Liang Yuan, Kexin Li, and Zhening Liu
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head pose estimation ,global attention block ,self-attention routing ,capsule network ,Science ,Astrophysics ,QB460-466 ,Physics ,QC1-999 - Abstract
Head pose estimation is an important technology for analyzing human behavior and has been widely researched and applied in areas such as human–computer interaction and fatigue detection. However, traditional head pose estimation networks suffer from the problem of easily losing spatial structure information, particularly in complex scenarios where occlusions and multiple object detections are common, resulting in low accuracy. To address the above issues, we propose a head pose estimation model based on the residual network and capsule network. Firstly, a deep residual network is used to extract features from three stages, capturing spatial structure information at different levels, and a global attention block is employed to enhance the spatial weight of feature extraction. To effectively avoid the loss of spatial structure information, the features are encoded and transmitted to the output using an improved capsule network, which is enhanced in its generalization ability through self-attention routing mechanisms. To enhance the robustness of the model, we optimize Huber loss, which is first used in head pose estimation. Finally, experiments are conducted on three popular public datasets, 300W-LP, AFLW2000, and BIWI. The results demonstrate that the proposed method achieves state-of-the-art results, particularly in scenarios with occlusions.
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- 2023
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50. Associations of acrylamide with non-alcoholic fatty liver disease in American adults: a nationwide cross-sectional study
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Zhening Liu, Jinghua Wang, Shenghui Chen, Chengfu Xu, and Yu Zhang
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Fatty liver disease ,Acrylamide ,Association ,Risk ,Industrial medicine. Industrial hygiene ,RC963-969 ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Acrylamide (AA) is a toxicant to humans, but the association between AA exposure and the risk of non-alcoholic fatty liver disease (NAFLD) remains unclear. In this study, our objective is to examine the cross-sectional association between AA exposure and the risk of NAFLD in American adults. Methods A total of 3234 individuals who took part in the National Health and Nutrition Examination Survey (NHANES) 2003–2006 and 2013–2016 were enrolled in the study. NAFLD was diagnosed by the U.S. Fatty Liver Index. Multivariable logistic regression models were applied to estimate the association between AA and NAFLD in the whole group and the non-smoking group. Results We discovered that in the whole group, serum hemoglobin adducts of AA (HbAA) were negatively associated with the prevalence of NAFLD after adjustment for various covariables (P for trend
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- 2021
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