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Variable projection algorithms with sparse constraint for separable nonlinear models

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Control Theory and Technology 2024年第1期22卷 135-146页

作者： hui-Lang Xu Guang-Yong Chen Si-qing Cheng Min Gan Jing Chen College of Computer and Data Science Fuzhou UniversityFuzhou350116FujianChina Fujian Key Laboratory of Network Computing and Intelligent Information Processing Fuzhou UniversityFuzhou350116FujianChina Key Laboratory of Intelligent Metro of Universities in Fujian Fuzhou UniversityFuzhou350116FujianChina Engineering Research Center of Big Data Intelligence Ministry of EducationFuzhou UniversityFuzhou350116FujianChina School of Science Jiangnan UniversityWuxi214122JiangsuChina

Separable nonlinear models are widely used in various fields such as time series analysis, system modeling, and machine learning, due to their flexible structures and ability to capture nonlinear behavior of data. However, identifying the parameters of these models is challenging, especially when sparse models with better interpretability are desired by practitioners. Previous theoretical and practical studies have shown that variable projection (VP) is an efficient method for identifying separable nonlinear models, but these are based on \(L_2\) penalty of model parameters, which cannot be directly extended to deal with sparse constraint. Based on the exploration of the structural characteristics of separable models, this paper proposes gradient-based and trust-region-based variable projection algorithms, which mainly solve two key problems: how to eliminate linear parameters under sparse constraint;and how to deal with the coupling relationship between linear and nonlinear parameters in the model. Finally, numerical experiments on synthetic data and real time series data are conducted to verify the effectiveness of the proposed algorithms.

关键词： Variable projection(VP) Non-smooth constraint Separable nonlinear models

Influence of soaking Malus domeri(Bois)*** on gut microbiota and metabolites of long-living elderly individuals in Hezhou city,Guangxi,China

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Food Science and Human Wellness 2024年第3期13卷 1311-1321页

作者： hui Nie Zhongyang Gao Yanghe Luo Yajuan Wang Feiyang wu Guangqing Mu Xiaomeng wu School of Food Science and Technology Dalian Polytechnic UniversityDalian 116034China Dalian Probiotic Function Research Key Laboratory Dalian Polytechnic UniversityDalian 116034China Guangxi Key Laboratory of Health Care Food Science and Technology Hezhou UniversityHezhou 542899China

To investigate the effects of drinking the soaking of Malus domeri(Bois)*** on gut microbiota and metabolites of long-living elderly individuals in Hezhou city,Guangxi,*** has been reported that longevity is closely related to metabolism and the gut *** 16S rRNA sequencing and liquid chromatography-mass spectrometry(LC-MS)were used to analysis fecal samples and explore the factors affecting longevity in the ***,we discovered,that elderly individuals who had been drinking the soaking of ***(Bois)*** for a long time exhibited higher diversity of the gut microbiota than without drinking the soaking,*** proportions of Ruminococcaceae and Prevotella were decreased in those who did not drink this *** addition,a total of 106 metabolites were characterized,and the people of long-lived people(>90 years old)and elderly people(<90 years old)who drinking soaking of ***(Bois)*** significantly altered the gut microbiota and upregulated levels of haplopine,farnesol,genipic acid,momordicinin,2-hydroxyestrone,hydroxyphenyllactic acid,caffeic acid,sophoraflavanone B,and soyasaponin *** preliminarily determined that ***(Bois)*** consumption may be an important factor affecting longevity in this area.

关键词： Longevity Malus domeri(Bois)Chev.leaves Gut microbiota Metabolomics

Quantitative understanding of phase segregation behaviors by precisely building discrete oligo-ester-b-oligo-olefin block copolymers

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Science China Chemistry 2024年第3期67卷 1008-1016页

作者： Yuxin Liu Rui Tan Haibing wu Xue-hui Dong Zhengbiao Zhang College of Chemistry Chemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China State Key Laboratory of Radiation Medicine and Protection Soochow UniversitySuzhou 215123China South China Advanced Institute for Soft Matter Science and Technology School of Molecular Science and EngineeringSouth China University of TechnologyGuangzhou 510640China

Block copolymers(BCPs) with high Flory-Huggins parameter(χ) and balanced surface energy have aroused tremendous interest for ultra-small nanopatterns ***,high χ and balanced surface energy are generally *** fine tune of chain structure might be a useful way to achieve high χ and balanced surface *** realize this,the block copolymer with exactly uniform chain structure,i.e.,defined molecular structure,is highly desirable for accurately evaluating the phase ***,two kinds of discrete oligo ester-b-oligo olefin block copolymers with different chemical structures(oligo lactic acid-boligo olefin BCP,oLA_(n)-b-C_(m);oligo phenyl lactic acid-b-oligo olefin BCP,oPL_(n)-b-C_(m)) were modularly synthesized through iterative growth *** effect of chain structure on segregation strength and surface properties was quantitatively investigated using the discrete BCPs as precise *** the one hand,introducing rigid and nonpolar phenyl groups into oligo ester block has a negligible effect on the chemical incompatibility,as confirmed by the identical high χ values of oLA_(n)-b-C_(m) and oPL_(n)-b-C_(m)(χ_(oLA/C)=0.21 and χ_(oPL/C)=0.19).On the other hand,the incorporation of nonpolar phenyl groups creates balanced surface energy,that is,the high χ and balanced surface energy were simultaneously achieved by oPL_(n)-b-C_(m).Therefore,sub-10 nm perpendicular nanopatterns can be easily produced upon brief thermal treatment,demonstrating its potential application in semiconductor manufacturing with ultra-small feature *** discrete BCP can serve as a quantitative and exquisite model to study the critical contribution of chain structures on phase separation behavior,providing insightful understanding to facilitate the potential application in the chip process.

关键词： discrete polymer iterative growth self-assembly highχ balanced surface

Reactive molecular dynamics insight into the thermal decomposition mechanism of 2,6-Bis(picrylamino)-3,5-dinitropyridine

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Defence Technology（防务技术） 2024年第3期33卷 134-146页

作者： Jianbo Fu hui Ren Xinzhou wu Yongjin Chen Mi Zhang Yazhi Cheng State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

2,6-bis(picrylamino)-3,5-dinitropyridine(PYX)has excellent thermostability,which makes its thermal decomposition mechanism receive much *** this paper,the mechanism of PYX thermal decomposition was investigated thoroughly by the ReaxFF-lg force field combined with DFT-B3LYP(6-311++G)*** detailed decomposition mechanism,small-molecule product evolution,and cluster evolution of PYX were mainly *** the initial stage of decomposition,the intramolecular hydrogen transfer reaction and the formation of dimerized clusters are earlier than the denitration *** the progress of the reaction,one side of the bitter amino group is removed from the pyridine ring,and then the pyridine ring is *** final products produced in the thermal decomposition process are CO_(2),H_(2)O,N_(2),and H_(2).Among them,H_(2)O has the earliest generation time,and the reaction rate constant(k_(3))is the *** clusters are formed during the decomposition of PYX,and the formation,aggregation,and decomposition of these clusters are strongly affected by *** low temperatures(2500 K-2750 K),many clusters are *** high temperatures(2750 K-3250 K),the clusters aggregate to form larger *** 3500 K,the large clusters decompose and become *** the late stage of the reaction,H and N in the clusters escaped almost entirely,but more O was trapped in the clusters,which affected the auto-oxidation process of ***'s initial decomposition activation energy(E_(a))was calculated to be 126.58 kJ/*** work contributes to a theoretical understanding of PYX's entire thermal decomposition process.

关键词： PYX Thermal decomposition ReaxFF-lg MD simulations Excellent thermostable explosives

Engineering CuMn Prussian blue analog-shelled nanobox for efficient electrochemical reduction of nitrate to ammonia

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Tungsten 2024年第4期6卷 833-844页

作者： Zi-Yi Yang Yu-Dong Li Dan Liu Mao-Sen Song Yang Gao qing-Ping wu En-Shan Han Yan-Zhen He Xiao-hui Yang School of Chemical Engineering and Technology Hebei University of Technology Key Laboratory of Bio-Based Material Science and Technology Northeast Forestry University Institute of Electrochemical Energy Storage Helmholtz-Zentrum Berlin für Materialien und Energie Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences

Electrocatalytic nitrate reduction reaction（ENRR） for ammonia synthesis is a promising strategy to relieve nitration contamination,as well as an alternative to the Haber-Bosch *** blue analogs（PBAs） are expected to be an electrocatalytic material with superior performance owing to their abundant active sites and open channel ***,most reported PBA materials possess low nitrate conversion and ammonia yield rates,which has led to a hindrance in their research of ***,CuMn-PBA-shelled nanoboxes（CuMn-PBA SNBs） synthesized through tannic acid etching and cation exchange approaches are demonstrated for efficient ammonia *** optimal CuMn-PBA SNBs electrode achieves a high nitrate conversion of 91.33% and ammonia selectivity of 98.87% in a 0.2 mol·L-1Na2SO4solution with100×10-6NO3--N at-1.4 V ***,the CuMn-PBA SNB s electrode exhibits exceptional stability throughout a 30 h electrocatalytic *** outstanding electrochemical performance is attributed to the unique hollow nanobox structure with abundant active sites and high-throughput transport pathways for ions' aspects.

关键词： Acid etching Ammonia synthesis Cation exchange Electrocatalytic nitrate reduction Nanobox Prussian blue analogs

Chain Dynamics Heterogeneity in Plasticized Poly(vinyl butyral)(PVB) as Elucidated by Solid-State NMR

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Chinese Journal of Polymer Science 2024年第1期42卷 113-124,I0010页

作者： Jing Lv Xu Chen Zi-Shuo wu Ya-hui Li Wei Chen National Synchrotron Radiation Laboratory Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmCAS Key Laboratory of Soft Matter ChemistryUniversity of Scienceand Technology of ChinaHefei 230026China

The chain dynamics heterogeneity of the poly(vinyl butyral)(PVB) plasticized by triethylene glycol bis(2-ethylhexa noate)(TEG-EH) was investigated by various solid-state NMR *** plasticized PVB shows two domains in distinct molecular dynamics differences,namely,rigid and soft domains,where the latter is the plasticizer-rich *** time domain low field NMR was first used to investigate the dynamics heterogeneity of the plasticized PVB,and the results show the decreasing activated energy of components in the soft domain of plasticized PVB(E_a=20.2 kJ/mol) as compared with that of the pristine one(E_a=24.3 kJ/mol).Detailed dynamics heterogeneity was obtained by high-field NMR with site-specific *** quadrupole-echo ~2H-NMR was adopted to elucidate the dynamics heterogeneity of the vinyl alcohol(VA) units,where only the hydroxyl group of VA is *** ~1H-^(13)C WISE NMR spectra show that there is not much difference in the mobility of the VB unit in PVB with and without plasticizer,whereas the glass transition temperature differed by approximately 53℃.This is further supported by Torchia's T_1 relaxation *** origin of such an unusual phenomenon is attributed to the critical role of the remaining VA(~22%) in the soft domain,where the VA units locally aggregate through hydrogen ***,the existence of a mobility gradient in the VB unit has been ***,the mobility difference for VB with different stereo-geometry(meso or racemic conformation) is observed for the first *** indicates the importance of modulating the ratio of meso over racemic VB for controlling the macroscopic perfo rmance of PVB.

关键词： Poly(vinyl butyral) Dynamics heterogeneity Plasticizer Solid state NMR

Elucidating and manipulating pressure-induced water intrusion–extrusion in tunable hydrophobic Co/Zn bimetallic ZIFs:Roles of pore size and hydrogen bond

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Nano Research 2024年第1期17卷 344-353页

作者： Diyi Fang Chuanlei Liu Yu Chen Qilong Peng Kongguo wu Yuxiang Chen Hao Jiang Yuan wu Benxian Shen Qiumin wu Di wu hui Sun International Joint Research Center of Green Energy Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China Alexandra Navrotsky Institute for Experimental Thermodynamics The Gene and Linda Voiland School of Chemical Engineering and BioengineeringMaterials Science and Engineeringand Department of ChemistryWashington State UniversityWashington 99163USA

Porous heterogeneous lyophobic systems(HLSs)find potential applications in energy restoring,dissipating,and ***,the development of controllable HLSs still lacks rational structure design of nanoporous materials matching the molecular sizes of adopted *** that,thoroughly understanding the underlying transportation mechanism in the confined nano channels is greatly *** this work,a series of Co/Zn bimetallic zeolitic imidazolate frameworks(ZIFs)with tunable structures were synthesized via regulating the Co to Zn ratios and employed to investigate the intrusion–extrusion of liquid water in confined *** characterizations confirm the heterometallic coordination in the Co/Zn-doped *** intrusion–extrusion experiments unlock the relationship between the intrusion pressure and the nanopore size and realize the evolution of the HLSs between molecular spring and *** addition,cycling tests indicate the reversible structure change of Co/Zn ZIFs encountering pressure-induced water *** combination with molecular dynamics simulations,we present that the water multimers intrude into nanopores of ZIFs in chain-like forms along with dissociation of hydrogen bonds(HBs).Water molecules in the pre-intrusion state exhibit reduced HBs in response to the increase of pressure and linear structure with 1.6–3.0 HBs on *** transition to the post-intrusion situation,the associative configuration of water tends to exhibit the tetrahedral ***,we highlight the roles of pore size and HB in synergically dominating the pressure-induced intrusion–extrusion of liquid water in hydrophobic ***,the present work can also guide the development of functional guest–host systems based on porous architectures.

关键词： heterometallic zeolitic imidazolate frameworks nanopore intrusion hydrogen bonds

Targeting colorectal cancer with Herba Patriniae and Coix seed:Network pharmacology,molecular docking,and in vitro validation

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3539-3558页

作者： Cheng-Lei Wang Bing-Wei Yang Xin-Yan Wang Xue Chen Wei-Dong Li Hao-Yu Zhai Ying wu Mu-YaoCui Jia-He wu qing-hui Meng Nan Zhang Department of Oncology Guang’anmen HospitalChina Academy of Chinese Medical SciencesBeijing 100053China The First Clinical Medical College Shaanxi University of Chinese MedicineXianyang 712046Shaanxi ProvinceChina Department of Scientific Research Management Guang’anmen HospitalChina Academy of Chinese Medical SciencesBeijing 100053China School of Clinical Medicine qinghai University Xining 810000Qinghai ProvinceChina School of Chinese Materia Medica Beijing University of Chinese MedicineBeijing 100029China

BACKGROUND Herba Patriniae and Coix seed(HC)constitute a widely utilized drug combination in the clinical management of colorectal cancer(CRC)that is known for its diuretic,anti-inflammatory,and swelling-reducing *** its efficacy has been demonstrated in a clinical setting,the active compounds and their mechanisms of action in CRC treatment remain to be fully *** To identify the active,CRC-targeting components of HC and to elucidate the mechanisms of action *** Active HC components were identified and screened using *** for each component were ***-related targets were obtained from human gene *** targets between HC and CRC were identified.A“drug-ingredient-target”network was created to identify the core components and targets *** Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)analyses were conducted to elucidate the key pathways *** docking between core targets and key components was *** vitro experiments validated core *** Nineteen active components of HC were identified,with acacetin as the primary active *** predictive analysis identified 454 targets of the active compounds in *** mapping with 2685 CRC-related targets yielded 171 intervention targets,including 30 core *** and KEGG analyses indicated that HC may influence the phosphoinositide 3-kinase(PI3K)/Akt signaling *** docking showed that acacetin exhibited an optimal interaction with AKT1,identifying PI3K,AKT,and P53 as key genes likely targeted by HC during CRC *** inhibited HT-29 cell proliferation and migration,as well as promoted apoptosis,in *** blotting analysis revealed increased p53 and cleaved caspase-3 expression and decreased levels of p-PI3K,p-Akt,and survivin,which likely contributed to CRC *** Acacetin,the principal active compound in the HC pair,inhibited the proliferati

关键词： Colorectal cancer Baijiangcao(Herba Patriniae) Yiyiren(Coix seed) Acacetin Proliferation Migration Apoptosis Network pharmacology

Acid-rock reaction kinetics in a two-scale model based on reaction order correction

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Petroleum Science 2024年第3期21卷 2089-2101页

作者： Xue-Song Li Ning Qi Ze-hui Zhang Lian Liu Xia-qing Li Xu-Hang Su School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Key Lab of Unconventional Oil&Gas Development Ministry of EducationChina University of Petroleum(East China)Qingdao26650ShandongChina SINOPEC Northwest Oilfield Branch Company Urumqi830011XinjiangChina Petroleum Engineering Technology Research Institute SINOPEC Shengli Oilfield CompanyDongying257000ShandongChina

The reaction order plays a crucial role in evaluating the response rate of ***,the conventional two-scale model typically assumes that the reaction order is constant as one,which can lead to significant deviations from *** address this issue,this study proposes a novel multi-order dynamic model for acid-rock reaction by combining rotating disk experimental data with theoretical *** numerical simulations,this model allows for the investigation of the impact of acidification conditions on different orders of reaction,thereby providing valuable insights for on-site *** analysis reveals that higher response orders require higher optimal acid liquid flow rates,and lower optimal H+diffusion coefficients,and demonstrate no significant correlation with acid ***,it is recommended to increase the displacement and use high-viscosity acid for reservoirs with high calcite content,while reducing the displacement and using low-viscosity acid for reservoirs with high dolomite content.

关键词： Reaction order Two-scale model Wormhole propagation Carbonate rocks Numerical simulation