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Earlier Menarche Can Be an Indicator of More Body Fat:Study of Sexual Development and Waist Circumference in Chinese Girls

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Biomedical and Environmental Sciences 2011年第5期24卷 451-458页

作者： guo XiaoYan ji ChengYe Institute of Child and Adolescent Health School of Public Health Peking University Health Science Center Beijing 100191 China

Objective This paper aims to study the relationship between body fat and sexual development in Chinese girls with different waist *** Six thousand one hundred and fifty six girls aged 6-19 were *** body weight,height,waist circumference,percentage of body fat and secondary sex characteristics were *** the subjects were divided into three groups：low class waist circumference,moderate class waist circumference and high class waist *** menarche percentages were analyzed by using the status *** menarche ages were analyzed by using the retrospective *** for mean age at entry into a pubertal stage and menarche were calculated by a probit *** The incidences of moderate class and high class waist circumstance were 20.94% and 25.27%,*** sexual development of the former was earlier than that of the *** percentages of the menarche were detected as high classmoderate classlow *** menarche ages were expressed as high classmoderate classlow *** A close association is found between the waist circumference and sexual development,especially the menarche *** with high class waist circumference are more vulnerable to earlier menarche and excess body *** is important to control the occurrence of central obesity through monitoring the change of waist circumference in puberty for girls＇ health.

关键词： Waist circumference Sexual development Menarche Body fat Girls

Elution of 17α 25-Norhopanes and Triaromatic Steroids from Weathered Soils by Mixed Triton X-100/Na_2SiO_3 Surfactant Solution

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Chemical Research in Chinese Universities 2012年第3期28卷 419-423页

作者： ji guo-dong ZHOU guo-hui Key Laboratory of Water and Sediment Sciences Ministry of EducationDepartment of Environmental EngineeringPeking UniversityBeo'ing 100871P.R.China

Sodium silicate（NazSiO3） was used to improve the elution of super heavy oil from weathered soil on an ultrasound-enhanced elution system by the solution containing 0-6000 mg/L surfactant Triton X-100. The removal extent of three markers[C26-34 17a 25-norhopanes, C26-28triaromatic steroids（TAS）, and C27-29methyl triaromatic steroids（MTAS）] was monitored. The average elution percentages of C26-34 norhopanes, C26-28 TAS, and C27-29 MTAS by Triton X-100/Na2SiO3 solutions were increased by 11%-13%, 9%-11% and 8%-13% with increasing Triton X-100 concentrations from 150 mg/L to 6000 mg/L. All the concentrations of Triton X-100 improved the elu- tion of TAS homologs containing fewer carbon atoms, whereas high concentrations improved the elution of larger 17a 25-norhopane and MTAS species. Addition of Na2SiO3 produced a noticeable increase in elution, particularly for lower-weight species. Scanning electron microscope（SEM） images and energy spectroscopy data reveal that surfac- rant solution of 6000 mg/L Triton X-100 and 4000 mg/L Na2SiO3 produced the greatest improvement in the elution of super heavy oil aggregates encapsulating the soil surface and the emulsification of particle dispersions. That is to say mixed solutions of Triton X-100 and Na2SiO3 in combination with ultrasound are a potential means of removing super heavy oil from weathered soils.

关键词： Triton X-100 surfactant solution Na2SiO3 17a 25-Norhopane Triaromatic steroid Biomarker

Identification of 5' capped structure and 3' terminal sequence of hepatitis E virus isolated from Morocco

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World Journal of Gastroenterology 2004年第14期10卷 2045-2049页

作者： guo-BingChen ji-HongMeng DepartmentofMicrobiologyandImmunology SoutheastUniversitySchoolofMedicineNanjing210009JiangsuProvinceChina

AIM: To examine 5′ and 3′ terminal sequences of hepatitis E virus (HEV) isolated from Morocco, to confirm 5′ methylated cap structure of the genome, and to investigate whether the 3′ UTR can be used to distinguish HEV genotypes instead of HEV complete genome ***: RNA ligase-mediated rapid amplification of cDNA ends (RLM-RACE) was employed to obtain the 5′ and 3′ terminal sequences of HEV Morocco strain. The 3′ UTR sequence of the Morocco strain was compared with that of the other 29 HEV strains using the DNAStar ***: The 5′ PCR product was obtained only from the RLM-RACE based on the capped RNA template. The 5′ UTR of the Morocco strain had 26 nucleotides, and the 3′ UTR had 65 nucleotides upstream to the polyA. The 5′ UTR between HEV strains had only point mutations of *** phylogenetic tree based on the sequences of 3′ UTR was not the same as that based on the complete ***: The genome of HEV Morocco strain was methylated cap structure. The 3′ terminal sequence can not be used for distinguishing HEV genotype for all HEV strains in place of the whole HEV genome sequence.

关键词： 5′帽结构 3′末端序列 HEV 戊型肝炎病毒摩洛哥 cDNA

Synthesis and Crystal Structure of a Dinuclear Complex:Bis[aqua(phen)(4-aba)copper(Ⅱ)nitrate(4-abaH)dihydrate]

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Chinese Journal of Structural Chemistry 2007年第3期26卷 263-266页

作者： LI Yan-guo CHEN Hong-ji Department of Material Science and Engineering Jinan University Guangzhou 510632 China

The title complex has been obtained by the reaction of copper nitrate trihydrate with 4-abaH （4-abaH = 4-aminobenzonic acid） and phenanthroline in ethanol solution, and its structure was determined by X-ray crystallography with the following data： monoclinic, space group C2/c, M, = 1266.13, Cu2C52H54N10O20, a = 25.884（5）, b = 10.205（2）, c = 20.849（4） A, β= 106.34（3）°, Z= 4, V= 5284.7（18） A^3, F（000） = 2616, Dc = 1.591 g/cm^3, μ = 0.896 mm ^-1, the final R = 0.0441 and wR = 0.1148 for 4200 observed reflections （Ⅰ 〉 2σ（Ⅰ））. In the molecule of the title complex, the asymmetric unit contains one half molecule, The Cu（Ⅱ） atom is five-coordinated by a tenninal water molecule, a bidentate phcnanthroline and two monodentate 4-ammobenzoate ligands forming a square pyramidal coordination environment. The two bridging 4-aminobenzoate ligands result in a dinuclear copper（Ⅱ） cluster with a short Cu-Cu distance （3.048 A） and a π-π rstacking between the adjacent phenanthroline rings （2.96 A）.

关键词： dinuclear copper(Ⅱ) phenanthroline 4-aminobenzonic acid crystal structure

Rotating spin-1/2 Bose–Einstein condensates in a gradient magnetic field with spin–orbit coupling

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Communications in Theoretical Physics 2020年第9期72卷 140-145页

作者： ji-guo Wang Yue-Qing Li Department of Mathematics and Physics Shijiazhuang TieDao UniversityShijiazhuang 050043China Institute of Applied Physics Shijiazhuang TieDao UniversityShijiazhuang 050043China

We study the ground-state phases of two-dimensional rotating spin-orbit coupled spin-1/2 Bose-Einstein condensates(BECs) in a gradient magnetic field. The competition between gradient magnetic field, spin-orbit coupling and rotation leads to a variety of ground-state phase structures. In the weakly rotation regime, as the increase of gradient magnetic field strength, the BECs experiences a phase transition from the unstable phase to the single vortex-line phase. The unstable phase presents the vortex lines structures along the off-diagonal direction. With magnetic field gradient strength increasing, the number of vortex lines changes accordingly. As the magnetic field gradient strength increases further, the single vortex-line phase with a single vortex line along the diagonal direction is formed. The phase diagram shows that the boundary between the two phases is linear with the relative repulsion λ?≥?1 and is nonlinear with λ?

关键词： Bose–Einstein condensate spin–orbit coupling gradient magnetic field

Quantum coherence and ground-state phase transition in a four-chain Bose–Hubbard model

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Communications in Theoretical Physics 2021年第8期73卷 182-188页

作者： ji-guo Wang Lin-Qi guo Ya-Fei Song Department of Mathematics and Physics Shijiazhuang TieDao UniversityShijiazhuang 050043China Institute of Applied Physics Shijiazhuang TieDao UniversityShijiazhuang 050043China

We study the quantum coherence and ground-state phase transition of a four-chain Bose–Hubbard model with the long-range interaction. In a special four-chain Bose–Hubbard model,i.e., each chain only has one optical potential, four types of the ground-state phases are discovered. The effects of the disorder, the on-site interaction and the long-range interaction on the quantum coherence are studied. For the system without the long-range interaction, the quantum coherence changes from one periodic oscillation to two periodic oscillations as the onsite interaction increases. By considering the long-range interaction, the quantum coherence goes back to one periodic oscillation again. The on-site interaction itself suppresses the quantum coherence, both the on-site interaction and long-range interaction together enhance the quantum coherence with the weak disorder. If the disorder strength is increased beyond a critical value,they start to suppress the quantum coherence. In a regular four-chain Bose–Hubbard model, i.e.,each chain has many optical potentials, the ground-state phase transitions are obtained by using the cluster Gutzwiller mean-field method. Exotic ground-state phases are found, i.e., superfluid phase, integer Mott insulator phase, supersolid phase and loophole insulator phase. The combination of the loophole insulator phase and the supersolid phase expands the lobes with the half-integer filling per site for the small ratio β = t_(‖)/t_(⊥).

关键词： Bose-Hubbard model quantum coherence ground-state phase transition

Automorphisms on the Poset of Products of Two Projections

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Acta Mathematica Sinica,English Series 2019年第8期35卷 1393-1401页

作者： Xin Hui WANG guo Xing ji School of Mathematics and Information Science Shaanxi Normal University

Let H be a complex Hilbert space with dim H ≥ 3 and B(H) the algebra of all bounded linear opera tors on H. Let ≤° be the diamond order on B(H), that is, for A, B ∈B(H), we say that A ≤° B if R(A)■ R(B), R(A^*)■ R(B^*) and AA^*A= AB^*A. Put Λ={PQ : P、Q ∈B(H) are projections}. In this paper, the relationship between Λ and ≤° is revealed and then the form of automorphisms of the poset (Λ,≤°) is given.

关键词： Partial order diamond order product of two projections automorphism

Machine learning model based on non-convex penalized huberized-SVM

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Journal of Electronic Science and Technology 2024年第1期22卷 81-94页

作者： Peng Wang ji guo Lin-Feng Li School of Finance and Economics Xizang Minzu UniversityXianyang712082China Research Center for Quality Development of Xizang Special Industries Xianyang712082China School of Computer Science and Technology Xinjiang UniversityUrumqi830017China

The support vector machine(SVM)is a classical machine learning *** the hinge loss and least absolute shrinkage and selection operator(LASSO)penalty are usually used in traditional ***,the hinge loss is not differentiable,and the LASSO penalty does not have the Oracle *** this paper,the huberized loss is combined with non-convex penalties to obtain a model that has the advantages of both the computational simplicity and the Oracle property,contributing to higher accuracy than traditional *** is experimentally demonstrated that the two non-convex huberized-SVM methods,smoothly clipped absolute deviation huberized-SVM(SCAD-HSVM)and minimax concave penalty huberized-SVM(MCP-HSVM),outperform the traditional SVM method in terms of the prediction accuracy and classifier *** are also superior in terms of variable selection,especially when there is a high linear correlation between the *** they are applied to the prediction of listed companies,the variables that can affect and predict financial distress are accurately filtered *** all the indicators,the indicators per share have the greatest influence while those of solvency have the weakest *** companies can assess the financial situation with the indicators screened by our algorithm and make an early warning of their possible financial distress in advance with higher precision.

关键词： Huberized loss Machine learning Non-convex penalties Support vector machine(SVM)

Enhancements of the Gaussian network model in describing nucleotide residue fluctuations for RNA

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Chinese Physics B 2021年第5期30卷 176-183页

作者： Wen-jing Wang ji-guo Su Key Laboratory for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China

Gaussian network model(GNM)is an efficient method to investigate the structural dynamics of ***,the application of GNM on RNAs is not as good as that on proteins,and there is still room to improve the *** this study,two novel approaches,named the weighted GNM(wGNM)and the force-constant-decayed GNM(fcdGNM),were proposed to enhance the performance of ENM in investigating the structural dynamics of *** wGNM,the force constant for each spring is weighted by the number of interacting heavy atom pairs between two *** fcdGNM,all the pairwise nucleotides were connected by springs and the force constant decayed exponentially with the separate distance of the nucleotide *** performance of these two proposed models was evaluated by using a non-redundant RNA structure database composed of 51 RNA *** calculation results show that both the proposed models outperform the conventional GNM in reproducing the experimental B-factors of RNA *** with the conventional GNM,the Pearson correlation coefficient between the predicted and experimental B-factors was improved by 9.85%and 6.76%for wGNM and fcdGNM,*** studies provide two candidate methods for better revealing the dynamical properties encoded in RNA structures.

关键词： Gaussian network model(GNM) B-factor RNA molecules