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| 1 | Efects of physical and chemical characteristics of surface sediments in the formation of shallow lake algae-induced black bloom显示文摘Surface sediments are closely related to lake black blooms. The dissolved oxygen(DO) distribution and its penetration depth in surface sediments as well as the migration and transformation of redox sensitive elements such as Fe and S at the sediment-water interface are important factors that could influence the formation of the black bloom. In this study, dredged and undredged sediment cores with diferent surface properties were used to simulate black blooms in the laboratory. The Micro Profiling System was employed to explore features of the DO and ∑ H2 S distribution at the sediment-water interface. Physical and chemical characteristics in sediments and pore waters were also analyzed. The results showed that sediment dredging efectively suppressed the black blooms. In the undredged treatment, DO penetration depth was only 50 μm. Fe2+concentrations, ∑ H2 S concentrations, and ∑ H2 S production rates were remarkably higher in surface sediments and pore waters compared to control and dredged treatments. Furthermore, depletion of DO and accumulation of Fe2+and ∑ H2 S in surface sediments and pore waters provided favorable redox environments and necessary material sources for the blooms. The study results proved that physical and chemical characteristics in surface sediments are important factors in the formation of the black bloom, and could provide scientific guidance for emergency treatment and long-term pre-control of black blooms. | Qiushi Shen Cheng Liu Qilin Zhou Jingge Shang Lei Zhang ChengXin Fan | 2013 | Journal of Environmental Sciences2013，25，12： | 43 |
| 2 | Significance of dredging on sediment denitrification in Meiliang Bay,China:A year long simulation study显示文摘An experiment for studying the effects of sediment dredging on denitrification in sediments was carried out through a one-year incubation of undredged (control) and dredged cores in laboratory. Dredging the upper 30 cm of sediment can significantly affect physico-chemical characteristics of sediments. Less degradation of organic matter in the dredged sediments was found during the experiment. Denitrification rates in the sediments were estimated by the acetylene blockage technique, and ranged from 21.6 to 102.7 nmol N2/(g dry weight (dw)·hr) for the undredged sediment and from 6.9 to 26.9 nmol N2/(g dw·hr) for dredged sediments. The denitrification rates in the undredged sediments were markedly higher (p<0.05) than those in the dredged sediments throughout the incubation, with the exception of February 2006. The importance of various environmental factors on denitrification was assessed, which indicated that denitrification was regulated by temperature. Nitrate was probably the key factor limiting denitrification in both undredged and dredged sediments. Organic carbon played some role in determining the denitrification rates in the dredged sediments, but not in the undredged sediments. Sediment dredging influenced the mineralization of organic matter and denitrification in the sediment; and therefore changed the pattern of inherent cycling of nitrogen. | Jicheng Zhong Chengxin Fan Lu Zhang Edward Hall Shiming Ding Bao Li Guofeng Liu | 2010 | Journal of Environmental Sciences2010，22，1： | 40 |
| 3 | Beyond hypoxia: Occurrence and characteristics of black blooms due to the decomposition of the submerged plant Potamogeton crispus in a shallow lake显示文摘Organic matter-induced black blooms(hypoxia and an offensive odor) are a serious ecosystem disasters that have occurred in some large eutrophic shallow lakes in China. In this study, we investigated two separate black blooms that were induced by Potamogeton crispus in Lake Taihu, China. The main physical and chemical characteristics, including color- and odor-related substances, of the black blooms were analyzed. The black blooms were characterized by low dissolved oxygen concentration(close to 0 mg/L), low oxidation-reduction potential, and relatively low pH of overlying water. Notably higher Fe2+and∑S2-were found in the black-bloom waters than in waters not affected by black blooms. The black color of the water may be attributable to the high concentration of these elements, as black FeS was considered to be the main substance causing the black color of blooms in freshwater lakes. Volatile organic sulfur compounds, including dimethyl sulfide, dimethyl disulfide, and dimethyl trisulfide, were very abundant in the black-bloom waters. The massive anoxic degradation of dead Potamogeton crispus plants released dimethyl sulfide, dimethyl disulfide, and dimethyl trisulfide, which were the main odor-causing compounds in the black blooms. The black blooms also induced an increase in ammonium nitrogen and soluble reactive phosphorus levels in the overlying waters. This extreme phenomenon not only heavily influenced the original lake ecosystem but also greatly changed the cycling of Fe, S, and nutrients in the water column. | Qiushi Shen Qilin Zhou Jingge Shang Shiguang Shao Lei Zhang Chengxin Fan | 2014 | Journal of Environmental Sciences2014，26，2： | 33 |
| 4 | Seasonal variation of potential denitrification rates of surface sediment from Meiliang Bay, Taihu Lake, China显示文摘The regulatory effects of environmental factors on denitrification were studied in the sediments of Meiliang Bay, Taihu Lake, in a monthly sampling campaign over a one-year period. Denitrification rates were measured in slurries of field samples and enrichment experiments using the acetylene inhibition technique. Sediment denitrification rates in inner bay and outer bay ranged from 2.8 to 51.5 nmol N2/(g dw (dry weight)·hr) and from 1.5 to 81.1 nmol N2/(g dw·hr), respectively. Sediment denitrification rates were greatest in the spring and lowest in the summer and early autumn, due primarily to seasonal differences in nitrate concentration and water temperature. For each site, positive and linear relationships were regularly observed between denitrification rate and water columnn itrate concentration. Of various environmental factors on denitrification that we assessed, nitrate was determined to be the key factor limiting denitrification rates in the sediments of Meiliang Bay. In addition, at the two sites denitrification rates were also regulated by temperature. The addition of organic substrates had no significant effect on denitrification rate, indicating that sediment denitrification was not limited by organic carbon availability in the sediments. Nitrate in the water column was depleted during summer and early autumn, and this suppressed effective removal of nitrogen from Taihu Lake by denitrification. | Jicheng Zhong, Chengxin Fan, Guofeng Liu, Lei Zhang, Jingge Shang, Xiaozhi GuState Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China. | 2010 | Journal of Environmental Sciences2010，22，7： | 29 |
| 5 | Impact of different benthic animals on phosphorus dynamics across the sediment-water interface显示文摘As a diagenetic progress, bioturbation influences solute exchange across the sediment-water interface (SWI). Different benthic animals have various mechanical activities in sediment, thereby they may have different effects on solute exchange across the SWI. This laboratory study examined the impacts of different benthic animals on phosphorus dynamics across the SWI. Tubificid worms and Chironomidae larvae were introduced as model organisms which, based on their mechanical activities, belong to upward-conveyors and gallery-diffusers, respectively. The microcosm simulation study was carried out with a continuous flow culture system, and all sediment, water, and worms and larvae specimens were sampled from Taihu Lake, China. To compare their bioturbation effects, the same biomass (17.1 g wet weight (ww)/m 2 ) was adopted for worms and larvae. Worms altered no oxygen penetration depth in sediment, while larvae increased the O 2 penetration depth, compared to the control treatment. Their emergence also enhanced sediment O 2 uptake. The oxidation of ferrous iron in pore water produced ferric iron oxyhydroxides that adsorbed soluble reactive phosphorus (SRP) from the overlying water and pore water. Larvae built obviously oxidized tubes with about 2 mm diameter and the maximum length of 6 cm in sediment, and significantly decreased ferrous iron and SRP in the pore water compared to the control and worms treatments. Worms constructed no visually-oxidized galleries in the sediment in contrast to larvae, and they did not significantly alter SRP in the pore water relative to the control treatment. The adsorption of ferric iron oxyhydroxides to SRP caused by worms and larvae inhibited SRP release from sediment. Comparatively, worms inhibited more SRP release than larvae based on the same biomass, as they successively renewed the ferric iron oxyhydroxides rich oxidation layer through their deposition. | Lei Zhang Xiaozhi Gu Chengxin Fan Jingge Shang Qiushi Shen Zhaode Wang Ji Shen | 2010 | Journal of Environmental Sciences2010，22，11： | 14 |
| 6 | Satellite UV-Vis spectroscopy:implications for air quality trends and their driving forces in China during 2005-2017显示文摘Abundances of a range of air pollutants can be inferred from satellite UV-Vis spectroscopy measurements by using the unique absorption signatures of gas species.Here,we implemented several spectral fitting methods to retrieve tropospheric NO_(2),SO_(2),and HCHO from the ozone monitoring instrument(OMI),with radiative simulations providing necessary information on the interactions of scattered solar light within the atmosphere.We analyzed the spatial distribution and temporal trends of satellite-observed air pollutants over eastern China during 2005-2017,especially in heavily polluted regions.We found significant decreasing trends in NO_(2) and SO_(2) since 2011 over most regions,despite varying temporal features and turning points.In contrast,an overall increasing trend was identified for tropospheric HCHO over these regions in recent years.Furthermore,generalized additive models were implemented to understand the driving forces of air quality trends in China and assess the effectiveness of emission controls.Our results indicated that although meteorological parameters,such as wind,water vapor,solar radiation and temperature,mainly dominated the day-to-day and seasonal fluctuations in air pollutants,anthropogenic emissions played a unique role in the long-term variation in the ambient concentrations of NO_(2),SO_(2),and HCHO in the past 13 years.Generally,recent declines in NO_(2) and SO_(2) could be attributed to emission reductions due to effective air quality policies,and the opposite trends in HCHO may urge the need to control anthropogenic volatile organic compound(VOC)emissions. | Chengxin Zhang Cheng Liu Qihou Hu Zhaonan Cai Wenjing Su Congzi Xia Yizhi Zhu Siwen Wang Jianguo Liu | 2019 | Light(Science & Applications)2019，8，1： | 11 |
| 7 | First observation of tropospheric nitrogen dioxide from the Environmental Trace Gases Monitoring Instrument onboard the GaoFen-5 satellite显示文摘The Environmental Trace Gases Monitoring Instrument(EMI)is the first Chinese satellite-borne UV–Vis spectrometer aiming to measure the distribution of atmospheric trace gases on a global scale.The EMI instrument onboard the GaoFen-5 satellite was launched on 9 May 2018.In this paper,we present the tropospheric nitrogen dioxide(NO2)vertical column density(VCD)retrieval algorithm dedicated to EMI measurement.We report the first successful retrieval of tropospheric NO_(2) VCD from the EMI instrument.Our retrieval improved the original EMI NO_(2) prototype algorithm by modifying the settings of the spectral fit and air mass factor calculations to account for the on-orbit instrumental performance changes.The retrieved EMI NO_(2) VCDs generally show good spatiotemporal agreement with the satellite-borne Ozone Monitoring Instrument and TROPOspheric Monitoring Instrument(correlation coefficient R of ~0.9,bias<50%).A comparison with ground-based MAX-DOAS(Multi-Axis Differential Optical Absorption Spectroscopy)observations also shows good correlation with an R of 0.82.The results indicate that the EMI NO_(2) retrieval algorithm derives reliable and precise results,and this algorithm can feasibly produce stable operational products that can contribute to global air pollution monitoring. | Chengxin Zhang Cheng Liu Ka Lok Chan Qihou Hu Haoran Liu Bo Li Chengzhi Xing Wei Tan Haijin Zhou Fuqi Si Jianguo Liu | 2020 | Light(Science & Applications)2020，9，1： | 11 |
| 8 | Influence of Chironomid Larvae on oxygen and nitrogen fluxes across the sediment-water interface(Lake Taihu,China)显示文摘The microscale distribution of oxygen,the nitrogen flux and the denitrification rates in sediment inhabited by chironomid larvae(Tanypus chinensis) were measured in eutrophic Lake Taihu,China.The presence of the chironomids in the sediment increased the oxygen diffusional flux from 10.4 ± 1.4 to 12.7 ± 2.5 mmol O 2 /(m 2 ·day).The burrows of the larvae represented 'hot spots' and strongly influenced the nitrogen cycles and diagenetic activity in the sediment.The results indicate that the bioturbation effects of Tanypus chinensis chironomid larvae increased the capacity of the sediment as a sink for nitrate and a source for ammonium.Nitrate influx and ammonium outflux were increased 8.8 and 1.7 times,respectively.Under bioturbation,the amount of nitrate consumed was greater than the amount of ammonium released.The total denitrification rate was also enhanced from 0.76 ± 0.34 to 5.50 ± 1.30 mmol N/(m 2 ·day).The net effect was that the bioturbated sediments acted as a net sink for inorganic nitrogen under direct and indirect bioturbation effects compared to the control. | Jingge Shang Lu Zhang Chengjun Shi Chengxin Fan | 2013 | Journal of Environmental Sciences2013，25，5： | 11 |
| 9 | Speciation of organic phosphorus in a sediment profile of Lake Taihu I:Chemical forms and their transformation显示文摘Organic phosphorus(nonreactive P,NRP)is a major component of P in sediments,but information about its chemical forms and dynamic transformation is limited.The chemical forms and dynamic behaviors of NRP in a sediment profile from Lake Taihu,a freshwater and eutrophic lake in China,were investigated.Five forms of NRP in the sediments were extracted based on a chemical fractionation technique,including easily labile NRP(NaHCO3-NRP),reactive metal oxide-bound NRP(HCl-NRP),humic acid-associated NRP(NaOH-NRPHA),fulvic acid-associated NRP(NaOH-NRPFA)and residual NRP(Res-TP).There were notable transformations with increasing sediment depth from the labile NaHCO3-NRP and NaOH-NRP pools to the recalcitrant HCl-NRP and Res-TP pools,which caused the NRP to become increasingly recalcitrant as the early diagenetic processes proceeded.Further analyses showed that the relative changes in contents of organic matter and reactive Fe oxides in the sediment profile triggered a competition for binding NRP fractions and led to the transformation of NRP.The results highlighted the importance of abiotic processes in regulating the diagenesis of organic P and its stability in sediments. | Di Xu Shiming Ding Bin Li Xiuling Bai Chengxin Fan Chaosheng Zhang | 2013 | Journal of Environmental Sciences2013，25，4： | 7 |
| 10 | Polygenetic Mineralization of the Early ProterozoicTongkuangyu Metaporphyry Copper Deposit inthe Zhongtiao Mountains,Shanxi Province显示文摘The Tongkuangyu metaporphyry copper deposit formed in the Early Proterozoic is tectonically located in the northern part of the Zhongtiao X -type palaeorift depression, on the southern margin of the North China platform. The genesis of the deposit has long been a hot subject of research of geologists working on mineral deposits. By means of the protolith reconstruction and fluid inclusion and isotope studies of host rocks of the deposits, the authors hold that this deposit is the product of combined exogenic, endogenic and metamorphic processes. Its formation mainly involved the following four stages: (1) the stage of formation of Mg- and Fe-rich tuffaceous variegated cupriferous sand-shale and K-rich biomodal volcanic rocks; (2) the early stage of formation of the metaporphyry copper deposit; (3) the stage of formation of the metaporphyry copper deposit; and (4) the stage of reworking of the metaporphyry copper deposit. | CHEN Wenming ZHANG Chengxin LU Jiren DANG Zefa LI Shuping CUI Wenbin NING Yuan | 1998 | Acta Geologica Sinica(English Edition)1998，72，2： | 7 |
| 11 | Short fixation with a 3‐rod technique for posterior hemivertebra resection in children younger than 5 years old显示文摘Importance Congenital hemivertebra is commonly treated with posterior hemivertebra resection with bilateral transpedicular fixation.However,implant‐related complications are common in children younger than 5 years old who undergo this surgical procedure.Objective To present the preliminary clinical and radiological outcomes of children younger than 5 years old treated by posterior hemivertebra resection and 3‐rod fixation technique.Methods From January 2016 to December 2017,14 consecutive patients of congenital scoliosis with 16 hemivertebrae were retrospectively reviewed,including 5 girls and 9 boys,aged between 25 and 55 months old(average,37.6 months).All patients underwent posterior hemivertebra resection with short fixation with bilateral pedicle screws and a convex lamina hook.Surgical complications and corrective outcomes were assessed based on the clinical charts and spinal radiographs with a minimum 24‐month follow‐up.Results The mean Cobb angle of the main curve was 38.4°before surgery,8.5°after surgery,and 8.7°at final follow‐up.In the compensatory cranial curve,the preoperative Cobb angle of 16.8°was corrected to 8.1°postoperatively and was 10.3°at final follow‐up.In the compensatory caudal curve,the preoperative Cobb angle of 15.9°improved to 5.3°postoperatively and was 7.8°at final follow‐up.The segmental kyphosis was corrected from 13.5°to 0.5°and was 1.1°at final follow‐up.There were no crankshaft phenomena,no proximal kyphosis,and no complications related to the instrumentation.Interpretation Posterior hemivertebra resection with instrumentation with bilateral pedicle screws and a convex lamina hook can achieve rigid fixation and deformity correction. | Dong Guo Ziming Yao Xinyu Qi Chengxin Li Xuejun Zhang | 2020 | Pediatric Investigation2020，4，2： | 4 |
| 12 | Speciation of organic phosphorus in a sediment profile of Lake Taihu Ⅱ.Molecular species and their depth attenuation显示文摘The understanding of organic phosphorus(P) dynamics in sediments requires information on their species at the molecular level,but such information in sediment profiles is scarce.A sediment profile was selected from a large eutrophic lake,Lake Taihu(China),and organic P species in the sediments were detected using solution phosphorus-31 nuclear magnetic resonance spectroscopy(31 P NMR) following extraction of the sediments with a mixture of 0.25 mol/L NaOH and 50 mmol/L EDTA(NaOH-EDTA) solution.The results showed that P in the NaOH-EDTA extracts was mainly composed of orthophosphate,orthophosphate monoesters,phospholipids,DNA,and pyrophosphate.Concentrations of the major organic P compound groups and pyrophosphate showed a decreasing trend with the increase of depth.Their half-life times varied from 3 to 27 years,following the order of orthophosphate monoesters > phospholipids DNA > pyrophosphate.Principal component analysis revealed that the detected organic P species had binding phases similar to those of humic acid-associated organic P(NaOH-NRP HA),a labile organic P pool that tends to transform to recalcitrant organic P pools as the early diagenetic processes proceed.This demonstrated that the depth attenuation of the organic P species could be partly attributed to their increasing immobilization by the sediment solids,while their degradation rates should be significantly lower than what were suggested in previous studies. | Shiming Ding Di Xu Xiuling Bai Shuchun Yao Chengxin Fan Chaosheng Zhang | 2013 | Journal of Environmental Sciences2013，25，5： | 3 |
| 13 | 溃疡性结肠炎相关结直肠癌的早期发现显示文摘结肠炎相关结直肠癌(CACC)是炎症性肠病(IBD)尤其是溃疡性结肠炎(UC)最严重的并发症之一,占所有IBD患者死亡原因的15%。由于相较于散发性结直甩接口,CACC预后不佳,死亡率较高,因此,早期发现是提高疗效的关键。结肠镜被推荐作为监测的首选方法,一些高级内镜成像技术也不断涌现。此外,最近不少研究都致力于采用不同的生物样本找到临床相关的监测标志物,这些标志物未来可能成为高效的筛查工具。所以说,对于病程较长的UC患者的癌变监测,最理想的监测方法目前仍存在争议。本文对早期发现CACC的相关研究进展进行了全面描述和总结。 | Yu Zhen Chengxin Luo Hu Zhang | 2018 | Gastroenterology Report2018，6，2： | 2 |
| 14 | PITPNC1 promotes the thermogenesis of brown adipose tissue under acute cold exposure显示文摘Brown adipose tissue (BAT) plays an essential role in non-shivering thermogenesis. The phosphatidylinositol transfer protein, cytoplasmic 1 (PITPNC1) is identified as a lipid transporter that reciprocally transfers phospholipids between intracellular membrane structures. However, the physiological significance of PITPNC1 and its regulatory mechanism remain unclear. Here, we demonstrate that PITPNC1 is a key player in thermogenesis of BAT. While Pitpnc1^(−/−) mice do not differ with wildtype mice in body weight and insulin sensitivity on either chow or high-fat diet, they develop hypothermia when subjected to acute cold exposure at 4℃. The Pitpnc1^(−/−) brown adipocytes exhibit defective β-oxidation and abnormal thermogenesis-related metabolism pathways in mitochondria. The deficiency of lipid mobilization in Pitpnc1^(−/−) brown adipocytes might be the result of excessive accumulation of phosphatidylcholine and a reduction of phosphatidic acid. Our findings have uncovered significant roles of PITPNC1 in mitochondrial phospholipid homeostasis and BAT thermogenesis. | Guoqing Tang Chengxin Ma Liangkui Li Shaoyan Zhang Fengsheng Li Jin Wu Yesheng Yin Qing Zhu Yan Liang Ru Wang He Huang Tong-Jin Zhao Hongyuan Yang Peng Li Feng-Jung Chen | 2022 | Science China(Life Sciences)2022，65，11： | 2 |
| 15 | A Bifunctional-Modulated Conformal Li/Mn-Rich Layered Cathode for Fast-Charging,High Volumetric Density and Durable Li-Ion Full Cells显示文摘Lithium-and manganese-rich(LMR)layered cathode materials hold the great promise in designing the next-generation high energy density lithium ion batteries.However,due to the severe surface phase transformation and structure collapse,stabilizing LMR to suppress capacity fade has been a critical challenge.Here,a bifunctional strategy that integrates the advantages of surface modification and structural design is proposed to address the above issues.A model compound Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2)(MNC)with semi-hollow microsphere structure is synthesized,of which the surface is modified by surface-treated layer and graphene/car-bon nanotube dual layers.The unique structure design enabled high tap density(2.1 g cm^(−3))and bidirectional ion diffusion pathways.The dual surface coatings covalent bonded with MNC via C-O-M linkage greatly improves charge transfer efficiency and mitigates electrode degradation.Owing to the synergistic effect,the obtained MNC cathode is highly conformal with durable structure integrity,exhibiting high volumetric energy density(2234 Wh L^(−1))and predominant capacitive behavior.The assembled full cell,with nanograph-ite as the anode,reveals an energy density of 526.5 Wh kg^(−1),good rate performance(70.3%retention at 20 C)and long cycle life(1000 cycles).The strategy presented in this work may shed light on designing other high-performance energy devices. | Zedong Zhao Minqiang Sun Tianqi Wu Jiajia Zhang Peng Wang Long Zhang Chongyang Yang Chengxin Peng Hongbin Lu | 2021 | Nano-Micro Letters2021，13，8： | 2 |
| 16 | Wind-wave affected phosphate loading variations and their relationship to redox condition in Lake Taihu显示文摘Variation of wind speed and the physico-chemical parameters, such as dissolved phosphate, ferrous and manganese in lake water were observed on site. Together with the chemistry analysis and simulated experiment in lab, the change of phosphate concentration in lake water was analyzed. The variation of ferrous/phosphate ratio explained that along with the enhancement of wind-wave effect and the oxidation ability of lake water, the effects of co-precipitation and removal of dissolved phosphate and iron in the lake water were reinforced. The ferrous/phosphate ratio in pore water was less than 2.0, demonstrating that the dissolved phosphate can be released into the overlying water. But, in the lake water, the stability of phosphate was controlled by the water dynamics.The phosphate release experiment showed that molecular release was only part of the whole and the direct discharge of phosphate in the pore water was also a part. The mineralization and biological process of suspended particulates in the water may be another important reason for the whole phosphate loadings. | ZHANG Lu ZHU Guangwei LUO Liancong GAO Guang ZHANG Yunlin QIN Boqiang FAN Chengxin | 2006 | Science China Earth Sciences2006，49，z1： | 2 |
| 17 | Control of postharvest Rhizopus rot of peach by microwavetreatment and yeast antagonist 显示文摘 | Hongyin Zhang Chengxin Fu Xiaodong Zheng | 2004 | Eur Food Res Technol2004，218，： | 1 |
| 18 | Caution Needed in Pretreatment of Sediments for Refining Phosphorus-31 Nuclear Magnetic Resonance Analysis: Results from a Comprehensive Assessment of Pretreatment with Ethylenediaminetetraacetic Acid显示文摘 | Ding ShiMing Bai Xiuling Fan Chengxin Zhang Lu | 2010 | EN2010，，5： | 1 |
| 19 | Postharvest biological control of gray mold rot of pear With Cryptococcus laurentii 显示文摘 | ZHANG Hongyin ZHENG Xiaodong FU Chengxin | 2005 | Postharvest Biology and Technology2005，35，： | 1 |
| 20 | Analysis of wear resistance and its mechanism in an Fe–Mn–Si–Cr–Ni shape memory alloy显示文摘 | Lin Chengxin Wang Guixin Wu Yandong Wang Jingang Zhang Jianjun | 2006 | Materials Science & Engineering A2006，，： | 1 |
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