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Clinical characteristics of 4355 patients with anterior cruciate ligament injury

Chinese Medical Journal 2013年第23期126卷 4487-4492页

作者： MEI Yu AO Ying-fang WANG jian-quan MA Yong ZHANG Xin WANG jia-ning ZHU jing-xian Institute of Sports Medicine Peking University Third HospitalBeijing 100191 China

Background Clinical features of anterior cruciate ligament （ACL） injury are important for its prevention,diagnosis and ***,few studies have reported such data,especially in *** purpose of this study was to describe the clinical characteristics of ACL injury on a large *** Between 1993 and 2007,a total of 4355 ACL deficient inpatients （612 athletes and 3743 non-athletes） were *** were collected using a special database *** the distributions of characteristics in different groups were compared and analyzed *** All subjects were confirmed with ACL tear during *** analysis revealed that the percentage of females in Athlete Group was significantly higher than that in Non-athlete Group （56.05％ vs.24.95％,P＜0.001）.This study also found that sports trauma was the main cause of ACL ***,basketball,judo,wrestling and track and field were the five most responsible activities for *** average injury time for athletes was significantly shorter than that for non-athletes （413.3 days vs.717.5 days,P＜0.001）.Three thousand nine hundred and eight cases were ordered ACL reconstruction （76.04％ single-bundle,18.30％ double-bundle）.Three hundred and forty-five patients （7.92％）were combined with other ligaments injuries,2667 （61.24％） were found with various grades of cartilage lesions,and 3377 （77.54％） were found with meniscal *** Sports trauma was the main cause of ACL tears in China,and reconstruction had become the principal surgical *** order to restore knee joint stability and reduce the incidence of cartilage and meniscal injury,patienttailored ACL reconstruction should be suggested at the right moment.

关键词： anterior cruciate ligament clinical characteristics incidence secondary injuries

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Theoretical Study on the Nitrogen-rich Derivatives Based on 1,2,4-Triazole and 1,2,3-Triazole Rings:an Extended Family of Power Performance Energetic Materials

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Chinese Journal of Structural Chemistry 2021年第9期40卷 1113-1121,1107页

作者： jia jing-xian PANG Yu YANG jing LI Min-xian MENG xiang-Jun GAO Xiao-Zhen LIU Li-Hua LRJ Meng-Na Department of Chemistry Tangshan Normal CollegeTangshan 063000China Yangquan Municipal Key Laboratory of Quantum Manipulation Shanxi Institute of TechnologyYangquan 045000China

The geometric and electronic structures of the derivatives of 4-nitro-5-(5-nitroimino-1,2,4-triazol-3-yl)-2H-1,2,3-triazolate(named A~J)are explored employing density functional theory(DFT)calculations at the B3LYP/6-311G^(**)level of *** on the optimized molecular structures,the heats of formation(HOF)are obtained,and the electronic properties,density and molecular sensitivity by characteristic heights(H_(50))are ***,the detonation performances(detonation velocity,detonation pressure)are estimated via Kamlet-Jacobs(K-J)*** B(H50=29.4 cm,ρ=1.91 g/cm^(3),Q=1563.04 cal/g,P=36.05 GPa,D=8.95 km/s)and H(H_(50)=31.9 cm,ρ=1.80 g/cm^(3),Q=1610.09 cal/g,P=37.31 GPa,D=9.12 km/s)have positive HOFs and remarkable insensitivity and good detonation performance,strongly suggesting them as the acceptable new-type *** initiating power surpasses conventional primary explosives,such as *** outstanding detonation power of compounds B and H contributes to its future prospects as a promising green primary explosive.

关键词： 4-nitro-5-(5-nitroimino-1,2,4-triazol-3-yl)-2H-1,2,3-triazolate high energy density materials density functional theory explosive

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DFT Study of Oxygenated Organic Pollutants Catalyzed by Molybdenum Oxides: Comparison of Reaction Mechanisms of MoO_x + HCHO(x = 1, 2, 3)

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Chinese Journal of Structural Chemistry 2019年第8期38卷 1229-1240页

作者： GAO Xiao-Zhen LIANG Yan YANG jing MENG xiang-Jun YANG Xiao-Chun jia jing-xian XUWen-Guo Yangquan Municipal Key Laboratory of Quantum Manipulation Shanxi Institute of TechnologyYangquan045000China Department of Chemistry Tangshan Normal CollegeTangshan063000China Institute for Physical Chemistry Beijing Institute of TechnologyBeijing100081China

The reaction mechanisms between formaldehyde and MoOx(x = 1, 2, 3) have been studied thoroughly in this paper. Five reaction pathways were found in three reactions(reactions Ⅰ to Ⅲ) through studying the mechanisms of MoOx(x = 1, 2, 3) catalyzing formaldehyde. Different products were obtained from three reactions. Of all three reactions, the barrier energy of Route ⅡA is the lowest(4.70 kcal/mol), which means in MoOx(x = 1, 2, 3), MoO2 has the best catalytic effect. Compared with other similar non-toxic treatments of formaldehyde, our barrier energy is the lowest. In this research, there was no good leaving group of the compound, so the mechanisms are addition reaction. We speculate that there must be an addition reaction to the more complex reactions to molybdenum oxides and aldehydes. As a chemical reagent for removing formaldehyde, it only absorbs formaldehyde and does not emit other toxic substances outward. Molybdenum oxides retain its original structures of the final products, which means it has excellent stability in the reaction of MoOx(x = 1, 2, 3) + HCHO. The mechanisms of all three reactions are addition reactions, but they are entirely different. As the number of oxygen atoms increases, the reaction mechanisms become simpler.

关键词： reaction mechanism formaldehyde elimination molybdenum oxides addition reaction barrier energy

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DFT Study of VOC Pollutants Catalyzed by Optimal MoxOy:Exploration of Reaction Mechanism of CH3COOH + MoO2

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Chinese Journal of Structural Chemistry 2020年第5期39卷 861-872页

作者： GAO Xiao-Zhen PANG Yu YANG jing YANG Xiao-Chun SHEN Yu-Long jia jing-xian MENG xiang-Jun Yangquan Municipal Key Laboratory of Quantum Manipulation Shanxi Institute of TechnologyYangquan 045000China Department of Chemistry Tangshan Normal CollegeTangshan 063000China Department of Atmospheric Sciences Texas A&M universityTX 77843USA

We propose the complicated catalytic mechanisms for the acetic acid molecule catalyzed by transition metal oxide MoO2 based on density functional theory *** geometries and energetic values of all stationaries and transition states involved in the three different reaction pathways(ChannelsⅠ,ⅡandⅢ)are reported and *** reaction mechanisms are fully different from that of MoxOy catalyzing volatile organic compounds(VOCs)in previous *** completely new mechanisms catalyzed by MoO2 for acetic acid have been discovered for the first ***Ⅰ(ⅠA andⅠB)andⅡare both addition reactions and channelⅢis hydrogen abstraction reaction by producing a leaving *** barrier energies of reaction are also compared with other catalytic reactions,showing that MoO2 catalyst expresses a lower barrier energy(8.22 kcal/mol)by addition reaction,which represents MoO2 tends to absorb acetic acid pollution gas via addition reaction rather than release toxic *** also means that MoO2 is a more effective and representative catalyst and is suitable for further study of catalytic carboxylic acids,so the reaction mechanisms may provide a useful theoretical guidance and solution for the catalysis of carboxylic acids.

关键词： reaction mechanism acetic acid elimination molybdenum dioxide addition reaction hydrogen abstraction reaction

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Molecular Design and Property Prediction of High Density 4-Nitro-5-(5-nitro-1,2,4-triazol-3-yl)-2H-1,2,3-triazolate Derivatives as the Potential High Energy Explosives

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Chinese Journal of Structural Chemistry 2022年第2期41卷 123-131,I0011页

作者： YANG jing PANG Yu LI Min-xian YANG Ge-Fei jia jing-xian MENG xiang-Jun LIU Li-Hua YANG Xiao-Chun GAO Xiao-Zhen Department of Chemistry Tangshan Normal CollegeTangshan 063000China School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China Yangquan Municipal Key Laboratory of Quantum Manipulation Shanxi Institute of TechnologyYangquan 045000China

To search for potential energetic materials with large energy density and acceptable thermodynamics and kinetics stability,twelve derivatives of 4-nitro-5-(5-nitro-1,2,4-triazol-3-yl)-2H-1,2,3-triazolate(named A~L)are designed and analyzed by using density functional theory(DFT)calculations at the B3LYP/6-311G**level of *** molecular heats of formation(HOF),electronic structures,impact sensitivity(H_(50)),oxygen balance(OB)and density(ρ)are investigated by isodesmic reaction method and physicochemical ***,the detonation velocity(D)and detonation pressure(P)are calculated to study the detonation performance by Kamlet-Jacobs(K-J)*** results show that new molecule J(H_(50)=36.9 cm,ρ=1.90g/cm^(3),Q=1912.46 cal/g,P=37.82 GPa,D=9.22 km/s,OB=0.00),compound A(H_(50)=27.9 cm,ρ=1.93 g/cm^(3),Q=1612.93 cal/g,P=38.90 GPa,D=9.19 km/s)and compound H(H_(50)=37.3 cm,ρ=1.97 g/cm^(3),Q=1505.06cal/g,P=37.20 GPa,D=9.01 km/s)present promising effects that are far better RDX and HMX as the high energy density *** calculations can provide useful information for the molecular synthesis of novel high energy density materials.

关键词： 4-nitro-5-(5-nitro-1,2,4-triazol-3-yl)-2H-1,2,3-triazolate energetic materials density functional theory explosive

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Downscaling Seasonal Precipitation Forecasts over East Africa with Deep Convolutional Neural Networks

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Advances in Atmospheric Sciences 2024年第3期41卷 449-464页

作者： Temesgen Gebremariam ASFAW jing-jia LUO Institute for Climate and Application Research(ICAR)/CIC-FEMD/KLME/ILCEC Nanjing University of Information Science and TechnologyNanjing 210044China Institute of Geophysics Space Science and Astronomy Addis Ababa UniversityAddis Ababa 1176Ethiopia

This study assesses the suitability of convolutional neural networks(CNNs) for downscaling precipitation over East Africa in the context of seasonal forecasting. To achieve this, we design a set of experiments that compare different CNN configurations and deployed the best-performing architecture to downscale one-month lead seasonal forecasts of June–July–August–September(JJAS) precipitation from the Nanjing University of Information Science and Technology Climate Forecast System version 1.0(NUIST-CFS1.0) for 1982–2020. We also perform hyper-parameter optimization and introduce predictors over a larger area to include information about the main large-scale circulations that drive precipitation over the East Africa region, which improves the downscaling results. Finally, we validate the raw model and downscaled forecasts in terms of both deterministic and probabilistic verification metrics, as well as their ability to reproduce the observed precipitation extreme and spell indicator indices. The results show that the CNN-based downscaling consistently improves the raw model forecasts, with lower bias and more accurate representations of the observed mean and extreme precipitation spatial patterns. Besides, CNN-based downscaling yields a much more accurate forecast of extreme and spell indicators and reduces the significant relative biases exhibited by the raw model predictions. Moreover, our results show that CNN-based downscaling yields better skill scores than the raw model forecasts over most portions of East Africa. The results demonstrate the potential usefulness of CNN in downscaling seasonal precipitation predictions over East Africa,particularly in providing improved forecast products which are essential for end users.

关键词： East Africa seasonal precipitation forecasting downscaling deep learning convolutional neural networks(CNNs)

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Al-containing Ge-rich IWV:rapid synthesis via interzeolite transformation and application in Baeyer-Villiger oxidation

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Science China Chemistry 2024年第7期67卷 2282-2291页

作者： Meichen jiao Chunmin jia Hao Xu Peng Wu xian-Ming Zhang School of Chemistry&Material Science Shanxi Normal UniversityTaiyuan 030006China Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China School of Chemistry Taiyuan University of TechnologyTaiyuan 030024China

Ge-containing Lewis acidic zeolites are typically synthesized using a conventional hydrothermal strategy from amorphous silica sources,through a long time-and energy-consuming approach limiting their wide *** study reports a rapid synthesis strategy for a series of IWV aluminogermanosilicate zeolites(T-x-Al)with a wide range of Si/Ge molar ratios(5–15)by interzeolite transformation of dealuminated FAU(DA-FAU).Notably,Ge-rich IWV could be obtained with crystallization time as short as one day by the equimolecular Si/Ge ratio *** effect of synthetic parameters was investigated and the obtained T-x-Al samples were characterized by XRD,SEM,EDS,ICP,^(29)Si and^(27)Al MAS NMR,FTIR,and N_(2)physisorption *** with a previously reported IWV germanosilicate(H-3),T-x-Al displayed a better catalytic activity in Baeyer-Villiger(BV)oxidation,attributed to the presence of the active framework Ge sites with the assistance of the extraframework Al *** cyclic catalysis tests revealed that the presence of framework Al species contributed to the stability of the ***,T-x-Al,with 14-membered ring(MR)supercages,outperformed the typical 12-MR Sn-beta catalyst in the BV oxidation of large ketone-like 2-admantanone,indicating a promising potential application in the macromolecular catalytic process.

关键词： Ge-rich IWV interzeolite transformation Al assistance Baeyer-Villiger oxidation

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Preface to special issue on celebrating the 100th anniversary of Xinjiang University

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Nano Research 2024年第1期17卷 1-4页

作者： Dianzeng jia Ruimao Hua xian-He Bu Yuliang Li State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830017China Department of Chemistry Tsinghua UniversityBeijing 100084China School of Materials Science and Engineering Nankai UniversityTianjin 300350China CAS Key Laboratory of Organic Solids Institute of ChemistryChinese Academy of SciencesBeijing 100190China

Xinjiang University originated from Xinjiang College of Russian Language,Political Science and Law in *** 1935 and 1960,the college was re-organized and re-named as Xinjiang College and Xinjiang University,*** 1978,Xinjiang University was appointed by the State Council as the only national key university in *** 1997,it was designated as one of the first batch of key construction universities in the“211 Project”of *** 2000,Xinjiang University was rebuilt through merging with Xinjiang Institute of Technology.

关键词： Xinjiang anniversary originated

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The Forecast Skills and Predictability Sources of Marine Heatwaves in the NUIST-CFS1.0 Hindcasts

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Advances in Atmospheric Sciences 2024年第8期41卷 1589-1600页

作者： jing MA Haiming XU Changming DONG jing-jia LUO Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/KLME/ILCEC/Institute of Climate and Application Research(ICAR) Nanjing University of Information Science and TechnologyNanjingJiangsu 210044China

Using monthly observations and ensemble hindcasts of the Nanjing University of Information Science and Technology Climate Forecast System(NUIST-CFS1.0) for the period 1983–2020, this study investigates the forecast skill of marine heatwaves(MHWs) over the globe and the predictability sources of the MHWs over the tropical oceans. The MHW forecasts are demonstrated to be skillful on seasonal-annual time scales, particularly in tropical oceans. The forecast skill of the MHWs over the tropical Pacific Ocean(TPO) remains high at lead times of 1–24 months, indicating a forecast better than random chance for up to two years. The forecast skill is subject to the spring predictability barrier of El Nino-Southern Oscillation(ENSO). The forecast skills for the MHWs over the tropical Indian Ocean(TIO), tropical Atlantic Ocean(TAO), and tropical Northwest Pacific(NWP) are lower than that in the TPO. A reliable forecast at lead times of up to two years is shown over the TIO, while a shorter reliable forecast window(less than 17 months) occurs for the TAO and ***, the forecast skills for the TIO, TAO, and NWP are seasonally dependent. Higher skills for the TIO and TAO appear in boreal spring, while a greater skill for the NWP emerges in late summer-early autumn. Further analyses suggest that ENSO serves as a critical source of predictability for MHWs over the TIO and TAO in spring and MHWs over the NWP in summer.

关键词： marine heatwaves NUIST-CFS1.0 hindcasts forecast skill predictability source ENSO

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Mutual Information Maximization via Joint Power Allocation in Integrated Sensing and Communications System

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China Communications 2024年第2期21卷 129-142页

作者： jia Zhu Junsheng Mu Yuanhao Cui Xiaojun jing School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

In this paper, we focus on the power allocation of Integrated Sensing and Communication(ISAC) with orthogonal frequency division multiplexing(OFDM) waveform. In order to improve the spectrum utilization efficiency in ISAC, we propose a design scheme based on spectrum sharing, that is,to maximize the mutual information(MI) of radar sensing while ensuring certain communication rate and transmission power constraints. In the proposed scheme, three cases are considered for the scattering off the target due to the communication signals,as negligible signal, beneficial signal, and interference signal to radar sensing, respectively, thus requiring three power allocation schemes. However,the corresponding power allocation schemes are nonconvex and their closed-form solutions are unavailable as a consequence. Motivated by this, alternating optimization(AO), sequence convex programming(SCP) and Lagrange multiplier are individually combined for three suboptimal solutions corresponding with three power allocation schemes. By combining the three algorithms, we transform the non-convex problem which is difficult to deal with into a convex problem which is easy to solve and obtain the suboptimal solution of the corresponding optimization problem. Numerical results show that, compared with the allocation results of the existing algorithms, the proposed joint design algorithm significantly improves the radar performance.

关键词： coexistence communications multicarrier radar mutual information spectrum sharing

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