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| 1 | Structure of MERS-CoV spike receptor-binding domain complexed with human receptor DPP4显示文摘最近的尖铁 glycoprotein (S) 鉴别中东呼吸症候群 coronavirus (MERS-CoV ) 指向细胞的受体, dipeptidyl peptidase 4 (DPP4 ) 。顺序比较和当模特儿的分析在病毒的尖铁上揭示了一个通常认为的受体绑定领域(RBD ) ,它调停这个相互作用。我们报导 3.0 Å MERS-CoV RBD 的决定水晶结构跳了到人的 DPP4 的细胞外的领域。我们的结果证明 MERS-CoV RBD 由一个核心和受体绑定子域组成。受体绑定子域与 DPP4 β 交往;推进器然而并非它的内在的 hydrolase 领域。MERS-CoV RBD 和相关 SARS-CoV RBD 分享他们的核心子域的结构的类似的高度,但是在受体绑定子域是尤其是分叉的。Mutagenesis 研究在为到 DPP4 和入口的病毒的绑定是批评的进目标房间的受体绑定子域识别了几关键残余。在在 MERS-CoV RBD 和 DPP4 之间的接口的原子细节提供病毒和受体相互作用的结构的理解,它能对 MERS-CoV 感染指导治疗学和疫苗的开发。 | Nianshuang Wang Xuanling Shi Liwei Jiang Senyan Zhang Dongli Wang Pei Tong Dongxing Guo Lili Fu Ye Cui Xi Liu Kelly C Arledge Ying-Hua Chen Linqi Zhang Xinquan Wang | 2013 | Cell Research2013，23，8： | 26 |
| 2 | Response of soil heat-water processes to vegetation cover on the typical permafrost and seasonally frozen soil in the headwaters of the Yangtze and Yellow Rivers显示文摘The response of soil temperature and moisture to vegetative cover in the active layer of permafrost and seasonally frozen soil were assessed and compared. Soil temperature and moisture, under a range of vegetation covers (92%, 65% and 30%) in the permafrost and vegetation covers (95%, 70%―80%, 40%―50% and 10%) in the seasonally frozen soil, were measured on a daily basis. A decline in vege-tation cover led to a decrease in the integral of freezing depth of active permafrost layer, but an increase in seasonally frozen soil. The maximum invasion depth and duration of the negative isotherm during the frozen period and of the positive isotherm during the non-frozen period clearly increased when vegetation cover declined. With a reduction of vegetation cover, the soil moisture in the active layer of the permafrost decreased for depths of 0.20―0.60 m, but increased for depths of 0.60―0.80 m, while for seasonally frozen soil, soil moisture of the entire profile (0.10―1.20 m) increased. Variation in vegetation cover alters soil heat-water processes, but the response to it is different between permafrost and seasonally frozen soil. | HU HongChang WANG GenXu WANG YiBo LIU GuangSheng LI TaiBing REN DongXing | 2009 | Chinese Science Bulletin2009，54，7： | 18 |
| 3 | Global overview of research progress and development of precision maize planters显示文摘Maize is the most important crop for food and widely used for industrial materials,leading to its increasing demand all over the world.Precision planting is the effective method to increase maize yield.To meet the agronomic requirement of precision planting,different kinds of precision maize planters were developed.However,because of the difference of geographical environment,cropping system,farm scale and economic status among different countries,types of maize planters are various and the technologies involved are at different levels.This paper summarizes the precision maize planters currently available in the world and classifies them into four types:precision planters for tilled-land,minimum/no tilled-land,hilly&small land,and cold&arid land.Detailed characteristics have been provided for some typical precision planters and comparisons were made as to their suitability under particular working conditions.High-efficiency and high-accuracy are the main features of precision planters for tilled-land,while the ability to clean residue from seed rows and prevent planters to be blocked are the important function of precision planters for minimum/no tilled-land.To fit for hilly&small land,planters should be light-weighted and small-sized,and to warm up soil and keep moisture,planters for cold&arid land should be equipped with plastic-film mulching mechanism.Finally,developing trend of precision planting technology was analyzed and suggestions,including policy support and technical improvement,were made for developing countries to make suitable precision maize planters according to the local geographical conditions and cropping systems. | Yang Li Yan Bingxin Cui Tao Yu Yiming He Xiantao Liu Quanwei Liang Zhijie Yin Xiaowei Zhang Dongxing | 2016 | International Journal of Agricultural and Biological Engineering2016，9，1： | 17 |
| 4 | Estimation of the Effects of Maize Straw Return on Soil Carbon and Nutrients Using Response Surface Methodology显示文摘Straw incorporation is generally considered an effective agricultural management practice that improves nutrient cycling and maintains soil fertility. To study the interactive effects of straw returning factors on soil organic carbon and available nutrients, a17-month(May 6, 2016 to October 6, 2017) experiment was conducted on straw incorporation by using response surface methodology under a three-factor(straw length, amount, and burying depth), five-level quadratic orthogonal rotation experimental design. Weight was assigned to each indicator for soil carbon and nutrients and then a comprehensive indicator was established. Then, a second-order polynomial model of the three straw returning factors was established using response surface methodology. Results indicated that17 months after straw incorporation, straw amount and burying depth had significant effects on the comprehensive indicator of soil carbon and nutrients. Straw length and the interactions of straw amount and burying depth showed no significant effects on the comprehensive indicator of soil carbon and nutrients. It was concluded that 17 months after straw incorporation, the highest value of the comprehensive indicator of soil carbon and nutrients was achieved when the straw length, amount, and burying depth were approximately 17–20 cm, 740–840 g m^(-2), and 9–13 cm, respectively, which can be recommended as the most suitable parameters for use in straw returning in the study area. | ZHOU Dongxing SU Ye NING Yucui RONG Guohua WANG Guangdong LIU Di LIU Liyan | 2018 | Pedosphere2018，28，3： | 12 |
| 5 | Performance of no-till corn precision planter equipped with row cleaners显示文摘In the continuous annual wheat-corn cropping area of North China Plain,no-till planting that promotes soil conservation and crop yield while reducing operation cost has been gradually accepted by local farmers.However,previous wheat residue is the main limiting factor affecting the performance of existing planters in placing seeds at uniform spacing and optimum depth in residue covered fields.In order to solve this problem,a kind of ground-wheel-driven row cleaner was designed,developed and mounted on row units of a four-row pneumatic precision planter.The planter has two adjacent row units equipped with the newly designed row cleaners and the other two adjacent row units equipped with the commonly used inactive row cleaners.This was used for planting at three forward speeds(4 km/h,6 km/h and 8 km/h)into half residue(HR)and whole residue(WR)plots.The amount of residue removal,seeding depth,emergence rate and indices of uniformity in seed spacing(missing-seeding index,quality of feeding index and precision index)were measured.The newly designed row cleaner performed better with regard to residue removal,with the average percentage of residue cleared as 63.0%compared to 40.3%for the inactive row cleaner.For the HR and WR plots,percentage of residue cleared of the newly designed row cleaner reached 57.1%and 68.9%respectively,suggesting that the newly designed row cleaner can work more effectively at high residue level.By contrast,with the percentage of residue cleared of the inactive row cleaner as 43.1%and 37.5%in HR and WR plots,suggesting that the inactive row cleaner just can work effectively under low residue condition.Values of missing-seeding index,QFI,precision index,coefficient of variation of depth and percent emergence for the newly designed row cleaner under whole residue level are comparable to those for the inactive row cleaner under half residue level.The result indicates that the effect of using the newly designed row cleaner is equal to that of reducing surface residue,and can help to maintain the uniformity of seed spacing and seeding depth.The newly designed row cleaner generally performed better at forward speed of 6 km/h,based on the distribution of seeds along rows and seeding depth uniformity. | Yang Li Zhang Rui Gao Nana Cui Tao Liu Quanwei Zhang Dongxing | 2015 | International Journal of Agricultural and Biological Engineering2015，8，5： | 9 |
| 6 | Fabrication of highly efficient heterostructured Ag-CeO2/g-C3N4 hybrid photocatalyst with enhanced visible-light photocatalytic activity显示文摘On the basis of hydrothermal synthesis of Ag-CeO2 microspheres,Ag-CeO2/g-C3N4 composite photocatalyst with heterostructure was prepared by simple solvent evaporation of Ag-CeO2 and g-C3N4.To characterize the composition,structure,morphology and light absorption properties of the as-prepared Ag-CeO2/g-C3N4 composites,XRD,FTIR XPS,SEM,TEM,PL,BET and UV-vis DRS were used,respectively.The as-prepared photocatalyst was subjected to photocatalytic degradation of pollutants,and the prepared composite material has excellent photocatalytic activity for photodegradation of methylene blue(MB).The research shows that the photocatalytic properties of Ag-CeO2/g-C3N4 composites were related to the mass ratio of Ag-CeO2 microspheres and g-C3N4 nanosheets.When the ratio of Ag-CeO2 microspheres:g-C3N4 is 1:5,the composites have the highest photocatalytic activity,which was 9.6 and 3.3 times that of single Ag-CeO2 and g-C3N4,respectively.The improvement of photocatalytic activity is attributed to the heterostructure between the composite materials and the addition of noble metal silver,and the degradation of methylene blue by the visible light irradiation material is greatly improved.Finally,an attempt was made to analyze the principle of photocatalytic degradation of pollutants in prepared materials. | Chengbao Liu Dongxing Mao Jian Pan Junchao Qian Wenya Zhang Feng Chen Zhigang Chen Yenan Song | 2019 | Journal of Rare Earths2019，37，12： | 7 |
| 7 | Free vibration analysis of a pre-twisted sandwich blade with thermal barrier coatings layers显示文摘A rotating cantilever sandwich-plate model with a pre-twisted and pre-set angle has been developed to investigate the vibrational behavior of an aero-engine turbine blade with thermal barrier coating(TBC) layers. The classic von Karman plate theory and the first-order shear deformation theory are applied to derive the energy equations of the rotating TBC blade, in which the geometric shapes, the work ambient temperature, and the TBC material properties are considered. The Chebyshev-Ritz method is used to obtain the nature frequency of the rotating TBC blade. For static frequency and modal analysis, the finite-element method(FEM)is also applied to compare and validate the results from the Chebyshev-Ritz method. A good agreement is found among these kinds of methods. For dynamic frequency, the results are analyzed in detail concerning the influence of system parameters such as the thickness of the TBC layer, the working temperature, and the pre-twisted and pre-set angle. Finally, the Campbell diagram is demonstrated to analyze the resonance property of the cantilever sandwich TBC blade model. | CAO DongXing LIU BingYi YAO MingHui ZHANG Wei | 2017 | Science China(Technological Sciences)2017，60，11： | 7 |
| 8 | Environmental impact factors and mercury speciation in the sediment along Fujian and eastern Guangdong coasts显示文摘Concentrations of total mercury (THg) and methyl mercury (MeHg) were determined for 32 surface sediments collected along the coastal line of Fujian Province and eastern Guangdong Province. The spatial distributions of THg and MeHg and their environmental impact factors were investigated. The average concentrations of THg and MeHg in the sediments were 31.5 ng/g and 0.096 ng/g, respectively. Both sediment THg and MeHg concentrations showed relatively high value in the Minjiang Estuary and the coastal areas of Quanzhou and Putian. The concentrations overall decreased as the distance to the shoreline increased. The correlations among environmental impact factors and THg, MeHg were analyzed. The sediment THg concentration was highly correlated to the concentrations of organic matter, copper, total nitrogen (TN) and total phosphorus (TP), and significantly correlated to pH value of the bottom seawater and concentration of sediment sulfide. The sediment MeHg concentration was highly correlated to the concentrations of organic matter and copper, and significant correlated to the concentrations of sulfide, TN, TP and pH value of the bottom seawater. | ZHANG Yuanbiao HUO Yunlong LIU Xiyao KUANG Weiming YUAN Dongxing JI Weidong | 2013 | Acta Oceanologica Sinica2013，32，2： | 6 |
| 9 | Ionic liquids produce heteroatom-doped Pt/TiO2 nanocrystals for efficient photocatalytic hydrogen production显示文摘It is of great importance to develop facile strategies to synthesize catalysts with desirable compositions and structures for high-performance photocatalytic hydrogen generation. In this work, we put forward an ionic liquid assisted one-pot route for the synthesis of heteroatom-doped Pt/TiO2 composite material. This route is simple, environmentally benign and adjustable owing to the designable properties of ionic liquids. The as-synthesized Pt/TiO2 nanocrystals exhibit high activity and stability for the photocatalytic hydrogen generation under simulated solar irradiation. This method can be easily applied to the synthesis of various kinds of metal/TiO2 composites doped with desirable heteroatoms (e.g., F, Cl, Br, etc). | Xiuniang Tan Jianling Zhang Dongxing Tan Jinbiao Shi Xiuyan Cheng Fanyu Zhang Lifei Liu Bingxing Zhang Zhuizhui Su Buxing Han | 2019 | Nano Research2019，12，8： | 5 |
| 10 | Effect of Different Dietary Protein and Lipid Levels on the Growth,Body Composition,and Intestinal Digestive Enzyme Activities of Juvenile Yellow Drum Nibea albiflora(Richardson)显示文摘An 8-week feeding trial was conducted to determine the optimal dietary protein-to-lipid ratio for juvenile Nibea albiflora with an initial weight of(11.76 ± 0.20) g.Nine experimental diets containing different concentrations of protein(40%,47%,or 54%) and lipids(5%,9%,or 13%) in a 3 × 3 factorial experimental design were tested in triplicate groups of fish,while the protein-to-energy(P/E) ratios of the diets varied in the range of 19.74–28.32 mg k J^(-1).Results showed that fish fed diets containing 9% or 13% lipids with 54% protein exhibited significantly higher weight gains and specific growth rates than those fed other diets.The feed conversion rate of fish fed the diet with 40% protein and 5% lipids was significantly poorer than that of fish fed other diets.The protein efficiency rate of fish fed diets with 5% lipids was significantly lower than that of fish fed 9% or 13% lipid diets.Carcass lipid and energy contents were positively correlated with dietary lipid level regardless of protein level.Fish fed a 54% protein diet showed the highest trypsin activity.The intestinal lipase activity of fish fed the diet containing 13% lipids was significantly higher than that of fish fed 5% or 9% lipid diets.These results demonstrate the high protein dietary requirements of N.albiflora.A diet containing 54% protein and 9%–13% lipids with a P/E ratio of 26.2–27.81 mg protein k J^(-1) can be considered optimal for juvenile N.albiflora. | WANG Ligai HU Shenyu LOU Bao CHEN Dongxing ZHAN Wei CHEN Ruiyi LIU Feng XU Dongdong | 2018 | Journal of Ocean University of China2018，17，5： | 4 |
| 11 | Design and experimental study of seed precise delivery mechanism for high-speed maize planter显示文摘Aiming at improving the seed spacing uniformity of maize planter at high forward speed,a seed precise delivery mechanism driven by electric motor has been developed and evaluated in laboratory.The mechanism was designed to deliver single seed from seed meter to furrow.Seed’s movement from the seed release point in a seed meter to the seed delivery cavity in the belt was analyzed,the mathematical model of seed movement in the seed precise delivery mechanism was established based on seed delivery time analysis.A mechanical prototype was designed and associated control system was developed.The performance contrast experiment was conducted between a traditional seed tube and newly developed seed precise delivery mechanism,and test results indicated that the qualities of feed index of the seed precise delivery mechanism were higher than those of the traditional seed tube delivery mechanism,and the coefficients of variation of the seed precise delivery mechanism were lower than those of the traditional seed tube delivery mechanism when the forward speed of planter was set at 10 km/h,12 km/h and 14 km/h,respectively.It indicated the seed precise delivery mechanism significantly improved seed spacing uniformity of maize planter compared with the traditional seed tube delivery mechanism. | Quanwei Liu Tao Cui Dongxing Zhang Li Yang Yunxia Wang Xiantao He Mantao Wang | 2018 | International Journal of Agricultural and Biological Engineering2018，11，4： | 4 |
| 12 | Effects of pretreatment and HVOF sprayed cermet coating on fatigue properties of TC21 titanium alloy显示文摘The effects of grit blasting (GB),shot peening (SP) pretreatment and high velocity oxygen fuel(HVOF) sprayed WC-17Co cermet coating on the fatigue properties of the novel ultra-high strength TC21 titanium alloy were investigated with a rotating bending fatigue test machine.The basic properties and surface integrity of the coating were investigated by using X-ray diffraction (XRD),surface roughness meter,microscopic hardness tester,scanning electron microscopy (SEM) and X-ray stress test instruments.The results showed that the residual compressive stress could be introduced into the surface of TC21 alloy by GB and SP pretreatment,and that HVOF sprayed WC-17Co coating was compactly bonded with TC21 alloy substrate and it significantly improved the surface hardness of the substrate.However,there was a certain residual tensile stress in the sublayer of the coating.SP could significantly increase fatigue resistance of TC21 alloy due to the surface residual compressive stress.There was no significant effect on fatigue resistance by GB treatment due to the offset between the influence of surface residual compressive stress and the surface notch effect.The fatigue resistance of TC21 alloy was significantly reduced by HVOF WC-17Co coating prepared with GB pretreatment.This could be attributed to the relaxation of surface residual compressive stress during the HVOF heating process,pore defects and residual tensile stress distribution in the WC-17Co coating with low toughness,and the surface notch induced by GB.The fatigue resistance of TC21 alloy was slightly reduced by HVOF WC-17Co coating prepared with SP pretreatment.This was attributed to the offset between the advantage effect by SP and disadvantageous effect of WC-17Co coating and high temperature factor during the HVOF process. | DU DongXing LIU DaoXin MENG BaoLi ZHANG XiaoHua | 2013 | Science China(Technological Sciences)2013，56，4： | 4 |
| 13 | Supercritical CO2 produces the visible-light-responsive TiO2/COF heterojunction with enhanced electron-hole separation for highperformance hydrogen evolution显示文摘To construct the heterojunctions of TiO2 with other compounds is of great importance for overcoming its inherent shortages and improving the visible-light photocatalytic performance.Here we propose the construction of TiO2/covalent organic framework(COF)heterojunction with tight connection by a supercritical CO2(SC CO2)method,which helps bridging the transformation paths for photo-induced charge between T i02 and COF.The produced T i02/COF heterojunction performs a H2 evolution of 3,962 nmol·g^-1·h^-1 under visible-light irradiation,which is-25 times higher than that of pure TiO2 and 4.5 folds higher than that of TiO2/COF synthesized by the conventional solvothermal method.This study opens up new possibilities for constructing heterojunctions for solar energy utilization. | Lifei Liu Jianling Zhang Xiuniang Tan Bingxing Zhang Jinbiao Shi Xiuyan Cheng Dongxing Tan Buxing Han Lirong Zheng Fanyu Zhang | 2020 | Nano Research2020，13，4： | 4 |
| 14 | Distribution characteristics of total mercury and methylmercury in the topsoil and dust of Xiamen, China显示文摘The levels and distribution of mercury (Hg) species, including total mercury (THg) and methylmercury (MeHg) in the topsoil and dust collected from twenty sampling stations located in different land function areas of Xiamen, China, were investigated. The THg concentrations in topsoil ranged from 0.071 to 1.2 mg/kg, and in dust ranged from of 0.034 to 1.4 mg/kg. For stations where the THg of dust was less than 0.31 mg/kg, THg concentrations in the topsoil were significantly correlated to those in the corresponding dust (r = 0.597, n = 16, P = 0.014). The MeHg concentrations in topsoil were varied between 0.14 and 5.7 μg/kg. The ratios of MeHg/THg in the topsoil ranged from 0.069% to 0.74%. The range of MeHg concentration in the dust were 0.092–2.3 μg/kg. The ratios of MeHg/THg in the dust were at the same level as those in the topsoil. The MeHg concentrations in both topsoil and dust were linked to corresponding THg concentrations and soil organic matter. Neither THg nor MeHg concentration in the topsoil and dust was obviously linked to the land function. | LIANG Ying YUAN Dongxing LU Min GONG Zhenbin LIU Xiyao ZFIANG Zhen | 2009 | Journal of Environmental Sciences2009，21，10： | 3 |
| 15 | Ages and Hf isotopes of detrital zircons from the Permian strata in the engbatu area(Inner Mongolia) and tectonic implications显示文摘The Central Asian Orogenic Belt(CAOB) was built up through protracted accretion and collision of a variety of terranes/micro-continents during Neoproterozoice Mesozoic time. To understand potential links among Paleozoic subduction and accretionary processes that were operative during the development of the southeastern CAOB, we conducted a combined U-Pb and Hf-isotope analysis of detrital zircons from previously defined Devonian, Carboniferous and Early Permian strata in the Bengbatu area,Inner Mongolia. Detrital zircons from(meta-) sandstones in these strata commonly yield major Paleozoic age populations at ca. 300-261 Ma, 351-300 Ma and 517-419 Ma, and also give several Precambrian ages that range from 2687 Ma to 544 Ma. The youngest ages redefine the deposition of all these strata to be in the Middle Permian(Wordiane Capitanian) or later, much younger than previously considered.These ages, coupled with regional magmatic records, support an interpretation of most surrounding areas as possible detritus sources, including the Mongolian arcs to the north, the Northern Accretionary Orogen to the south, and the intervening Erenhote Hegenshan Ophiolite Belt. Zircons with magmatic ages of ca. 500-350 Ma and ca. 300-261 Ma display a large range of εHf(t) values(-13.97 to +15.31),whereas ca. 350-300 Ma zircons are dominated by positive εHf(t) values(+0.14 to +16.00). These results support the occurrence of two significant shifts of the zircon εHf(t) values, which has tectonic implications for the understanding of the Carboniferouse Permian evolution of the southeastern CAOB. A marked shift from mixed to positive zircon εHf(t) values at 350 -330 Ma likely manifests the incipient opening of the Hegenshan Ocean, due to the slab rollback of the subducting Paleo-Asian Oceanic lithosphere. Another shift from positive to mixed zircon εHf(t) values at ca. 300 Ma likely corresponds to a tectonic switch from syn-orogenic subduction-related to post-orogenic extensional setting, genetically related to the tectonic collapse of a formerly overthickened crust. | Bing Xu Guochun Zhao Jianhua Li Dongxing Liu Bo Wang Yigui Han Paul R. Eizenhofer Xiaoran Zhang Wenzhu Hou Qian Liu | 2019 | Geoscience Frontiers2019，10，1： | 2 |
| 16 | Effect of travel speed on seed spacing uniformity of corn seed meter显示文摘Both seeding performance of seed metering unit and travel speed of seed planter have significant effects on seeding quality,thereby affecting crop growth and yields.In order to determine the effects of different travel speeds on seed spacing uniformity,four different types of seed meters were evaluated at five different travel speeds on seed meter test bench and in field.The tested seed meters included a finger pickup seed meter,a scoop-wheel seed meter,an air-pressure type seed meter and an air-blowing type seed meter.The seeding performance of the horizontal distribution of seeds within a row was described by using the coefficient of variation,the quality of feed index,the multiple index and the miss-seeding index.Experiments were performed in laboratory and field,respectively.Results indicated that different travel speeds have statistically significant effects on seed spacing uniformity.The four types of seed meters performed better on the seed meter test bench than in the field.Coefficient of variation increases and quality of feed index decreases as the travel speed of seed planter increases.The best seed spacing uniformity was obtained with the air-pressure type seed meter,followed with the air-blowing type seed meter,the finger pickup seed meter and the scoop-wheel seed meter.There were considerable differences between the performances of the scoop-wheel seed meter in the bench test and field test;the seeding qualities were much better in the bench test than in the field test.The scoop-wheel seed meter is more sensitive to vibration than the other types of seed meters. | Liu Quanwei He Xiantao Yang Li Zhang Dongxing Cui Tao Qu Zhe Yan Bingxin Wang Mantao Zhang Tianliang | 2017 | International Journal of Agricultural and Biological Engineering2017，10，4： | 2 |
| 17 | Tidal- depositional systems of China's continental shelf, with special reference to the eastern Bohai Sea显示文摘 | Liu Zhenxia Xia Dongxing Berne S | 1998 | Marine Geology1998，145，34： | 1 |
| 18 | Tidal deposition systems of Chinas continental shelf, with special reference to the eastern Bohai Sea显示文摘 | Liu Zhenxia Xia Dongxing Bernfi S | 1998 | Marine Geology1998，145，34： | 1 |
| 19 | Opera- tional characteristics of miniature loop heat pipe with flat evaporator 显示文摘 | GAI Dongxing LIU Zhichun LIU Wei | 2009 | Heat and Mass Transfer2009，46，2： | 1 |
| 20 | Operational characteristecs of miniature loop heat pipe with flat evaporator显示文摘 | Dongxing Gai Zhichun Liu Wei Liu | 2009 | Heat Mass Transfer2009，46，2： | 1 |
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