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322篇 您的检索式:作者名="Yang Zhifeng"
    题名 作者 年代 出处 被引量
1Spatiotemporal dynamics of electric power consumption in Chinese Mainland from 1995 to 2008 modeled using DMSP/OLS stable nighttime lights data显示文摘电力消费(EPC ) 是为评估电力使用的基本索引之一。在 EPC 的空间与时间的动力学上获得及时、精确的数据为理解和电力资源的实际推广是关键的。在这研究,一个 EPC 模型从防卫气象学的卫星程序用稳定的夜间灯时间系列数据被开发运作的 Linescan 系统(DMSP/OLS ) 。模型被用来重建在在县的中国大陆的 EPC 的空间模式从 1995 ~ 2008 铺平。另外, EPC 的空间与时间的动力学被分析,并且下列结论被得出。(1 ) EPC 模型可靠地与约 70% 精确性在中国大陆代表了 EPC 的空间与时间的动力学。(2 ) 在中国大陆的大多数区域的 EPC 在对中等层次低,与显著时间、空间的变化;高级 EPC, 58.26% 在东方中国被集中。六城市的凝块(Beijing-Tianjin-Tangshan 区域, Shanghai-Nanjing-Hangzhou 区域,珀尔河三角洲,山东半岛,辽宁省,和四川盆中间南方) 说明了中国大陆的 10.69% 全部的区域,但是消费了 39.23% 电。(3 ) 在从 1995 ~ 2008,和 64% 大陆区域增加的中国大陆的大多数区域的 EPC 在 EPC 显示出重要增加。EPC 的中等增加从 1995 ~ 2008 在 61.62% 东方中国和 80.65% 华中被发现,而 75.69% 西方的中国没在 EPC 显示出重要增加。同时,分别地, 77.27% , 89.35% ,和 66.72% Shanghai-Nanjing-Hangzhou 区域,珀尔河三角洲,和山东半岛在 EPC 显示出高速度的增加。EPC 的中等增加发生在 71.12% Beijing-Tianjin-Tangshan 区域和 72.13% 并且辽宁省中间南方,分别地当没有重要增加发生在 56.34% 四川盆时。HE Chunyang MA Qun LI Tong YANG Yang LIU Zhifeng 2012Journal of Geographical Sciences2012,22,1:25
2Parameter determination to calculate water environmental capacity in Zhangweinan Canal Sub-basin in China显示文摘Zhangweinan canal sub-basin (ZWN) has the most serious water resource shortage and water pollution problems in north of China.To calculate the water environmental capacity in ZWN,determination methods for design flow rates and degradation coefficients were discussed in this study.Results showed that 90% and 50% hydrological guarantee flow rates were suitable to be the design flow rates for rainy and dry seasons,respectively.Degradation coefficients of COD Mn and NH 3 -N were 0.25 day -1 and 0.15 day -1 for branch streams and 0.5 day -1 and 0.25 day -1 for mainstreams,respectively in ZWN.With one-dimensional water quality simulation model,water environmental capacities were calculated to be 82,139 tons/yr for COD Mn and 2394 tons/yr for NH 3 -N in ZWN.Yingxia Li ,Ruzhi Qiu,Zhifeng Yang,Chunhui Li,Jingshan Yu State Key Laboratory of Water Environment Simulation,School of Environment,Beijing Normal University,Beijing,100875,China. 2010Journal of Environmental Sciences2010,22,6:23
3Differentiation of Human Bone Marrow Stromal Cells into Neural-Like Cells Induced by Sodium Ferulate in vitro显示文摘Human marrow stromal cells (hMSCs) are multipotential stem cells, capable of differentiating into bone, cartilage,fat and muscle. Several recent reports demonstrated that hMSCs have been also differentiated into neural cells.However, only a few reported inducers are applicable for clinical use. This work is to explore the effects of sodium ferulate (SF) on differentiation of hMSCs into neural cells in vitro. We found that hMSCs could be induced to the cells with typical neural morphology when cultured with SF. The cells express neural proteins, such as nestin,neuron-specific enolase (NSE) and glial fibrillary acidic protein (GFAP). About 30% of the hMSC-derived cells expressed nestin when cultured with SF for 3 h, but no expression was detected after 24 h. The percentages of positive cells for NSE or GFAP were about 67% and 39% separately at 6 h, and reached the plateau phage after treatment with SF for 3 days. The data suggest that SF can induce hMSCs to differentiate into neural-like cells in vitro.Yang Wang Zhifeng Deng Xianliang Lai Wei Tu 2005Cellular & Molecular Immunology2005,2,3:21
4Targeting ferroptosis suppresses osteocyte glucolipotoxicity and alleviates diabetic osteoporosis显示文摘Diabetic osteoporosis(DOP) is the leading complication continuously threatening the bone health of patients with diabetes. A key pathogenic factor in DOP is loss of osteocyte viability. However, the mechanism of osteocyte death remains unclear. Here, we identified ferroptosis, which is iron-dependent programmed cell death, as a critical mechanism of osteocyte death in murine models of DOP. The diabetic microenvironment significantly enhanced osteocyte ferroptosis in vitro, as shown by the substantial lipid peroxidation, iron overload, and aberrant activation of the ferroptosis pathway. RNA sequencing showed that heme oxygenase-1(HO-1) expression was notably upregulated in ferroptotic osteocytes. Further findings revealed that HO-1 was essential for osteocyte ferroptosis in DOP and that its promoter activity was controlled by the interaction between the upstream NRF2 and c-JUN transcription factors. Targeting ferroptosis or HO-1 efficiently rescued osteocyte death in DOP by disrupting the vicious cycle between lipid peroxidation and HO-1 activation, eventually ameliorating trabecular deterioration. Our study provides insight into DOP pathogenesis, and our results provide a mechanism-based strategy for clinical DOP treatment.Yiqi Yang Yixuan Lin Minqi Wang Kai Yuan Qishan Wang Pei Mu Jingke Du Zhifeng Yu Shengbing Yang Kai Huang Yugang Wang Hanjun Li Tingting Tang 2022Bone Research2022,10,3:19
5One-year clinical study of NeuroR egen scaffold implantation following scar resection in complete chronic spinal cord injury patients显示文摘The objective of this clinical study was to assess the safety and feasibility of the collagen scaffold, Neuro Regen scaffold, one year after scar tissue resection and implantation. Scar tissue is a physical and chemical barrier that prevents neural regeneration. However, identification of scar tissue is still a major challenge. In this study, the nerve electrophysiology method was used to distinguish scar tissue from normal neural tissue, and then different lengths of scars ranging from 0.5–4.5 cm were surgically resected in five complete chronic spinal cord injury(SCI) patients. The NeuroR egen scaffold along with autologous bone marrow mononuclear cells(BMMCs), which have been proven to promote neural regeneration and SCI recovery in animal models, were transplanted into the gap in the spinal cord following scar tissue resection. No obvious adverse effects related to scar resection or Neuro Regen scaffold transplantation were observed immediately after surgery or at the 12-month follow-up. In addition, patients showed partially autonomic nervous function improvement, and the recovery of somatosensory evoked potentials(SSEP) from the lower limbs was also detected. The results indicate that scar resection and Neuro Regen scaffold transplantation could be a promising clinical approach to treating SCI.Zhifeng Xiao Fengwu Tang Jiaguang Tang Huilin Yang Yannan Zhao Bing Chen Sufang Han Nuo Wang Xing Li Shixiang Cheng Guang Han Changyu Zhao Xiaoxiong Yang Yumei Chen Qin Shi Shuxun Hou Sai Zhang Jianwu Dai 2016Science China(Life Sciences)2016,59,7:18
6Effects of laser energy density on forming accuracy and tensile strength of selective laser sintering resin coated sands显示文摘Baozhu sand particles with size between 75 μm and 150 μm were coated by resin with the ratio of 1.5 wt.% of sands. Laser sintering experiments were carried out to investigate the effects of laser energy density(E = P/v), with different laser power(P) and scanning velocity(v), on the dimensional accuracy and tensile strength of sintered parts. The experimental results indicate that with the constant scanning velocity, the tensile strength of sintered samples increases with an increase in laser energy density; while the dimensional accuracy apparently decreases when the laser energy density is larger than 0.032 J·mm-2. When the laser energy density is 0.024 J·mm-2, the tensile strength shows no obvious change; but when the laser energy density is larger than 0.024 J·mm-2, the sample strength is featured by the initial increase and subsequent decrease with simultaneous increase of both laser power and scanning velocity. In this study, the optimal energy density range for laser sintering is 0.024-0.032 J·mm-2. Moreover, samples with the best tensile strength and dimensional accuracy can be obtained when P = 30-40 W and v = 1.5-2.0 m·s-1. Using the optimized laser energy density, laser power and scanning speed, a complex coated sand mould with clear contour and excellent forming accuracy has been successfully fabricated.Xu Zhifeng Liang Pei Yang Wei Li Sisi Cai Changchun 2014China Foundry2014,11,3:17
7Human placenta-derived mesenchymal stem cells loaded on linear ordered collagen scaffold improves functional recovery after completely transected spinal cord injury in canine显示文摘Traumatic spinal cord injury(SCI) is a major challenge in the clinic. In this study, we sought to examine the synergistic effects of linear ordered collagen scaffold(LOCS) and human placenta-derived mesenchymal stem cells(hPMSCs) when transplanted into completely transected beagle dogs. After 36 weeks observation, we found that LOCS+hPMSCs implants promoted better hindlimb locomotor recovery than was observed in the non-treatment(control) group and LOCS group. Histological analysis showed that the regenerated tissue after treatment was well integrated with the host tissue, and dramatically reduced the volume of cystic and chondroitin sulfate proteoglycans(CSPGs) expression. Furthermore, the LOCS+hPMSCs group also showed more neuron-specific βIII-tubulin(Tuj-1)-and NeuN-positive neurons in the lesion area, as well as axonal regeneration, remyelination and synapse formation in the lesion site. Additionally, dogs in the LOCS+hPMSCs group experienced enhanced sprouting of both ascending(CGRP-positive) sensory fibers and descending(5-HT-and TH-positive) motor fibers at the lesion area. All these data together suggested that the combined treatment had beneficial effects on neuronal regeneration and functional improvement in a canine complete transection model. Therefore, LOCS+hPMSCs implantation holds a great promise for bridging the nerve defect and may be clinically useful in the near future.Sufang Han Zhifeng Xiao Xing Li Huan Zhao Bin Wang Zhixue Qiu Zhi Li Xin Mei Bai Xu Caixia Fan Bing Chen Jin Han Yanzheng Gu Huilin Yang Qin Shi Jianwu Dai 2018Science China(Life Sciences)2018,61,1:15
8A Bayesian method for comprehensive water quality evaluation of the Danjiangkou Reservoir water source area, for the middle route of the South-to-North Water Diversion Project in China显示文摘Danjiangkou 水库是为在中国的 South-to-North 水转向工程的中间的线路的水来源。因此,它的水质量地位担心大。五水质量指示物(溶解的氧,高锰酸盐索引,氨氮,全部的氮,和全部的磷),在三点被测量监视地点( Danjiangkou 水库水坝, Hejiawan 和 Jiangbei 桥),调查变化趋势,并且在到2012年5月的从2006年1月的 Danjiangkou 水库区域的水质量的空间与时间的特征。我们然后使用了一个贝叶斯的统计方法包括地评估水质量。正常分发采样方法被用来计算可能性的,并且熵重量方法被用来为对的兴趣的变量决定指示物重量到学习。结果显示所有五指示物的集中在最后六年期间增加了。另外,在水库的水质量在湿季节期间是更坏的(从 5 月到 10 月) ,比在旱季期间(从 11 月到下一年的 4 月) 。总的来说,水的概率根据为在中国的表面水的环境优秀标准,属于类型 II 的优秀范畴是 27.7%-33.7% ,比它属于另外的四种水质量类型的大。营养素的增加的集中能导致 Danjiangkou 水库的超营养作用。这个方法减少了通常与决定指示物重量和人工的分类被联系的主观,完成更可靠的结果。这些结果显示 interbasin 水转向工程在 Danjiangkou 水库区域实现综合的水质量管理是重要的[出版摘要]Fangbing MA Chunhui LI Xuan WANG Zhifeng YANG Chengchun SUN Peiyu LIANG 2014Frontiers of Earth Science2014,8,2:14
9Impact of anthropogenic activities on the sediment microbial communities of Baiyangdian shallow lake显示文摘Microorganisms are recognized as sensors of external disturbance in freshwater ecosystems.In this study,sediment samples from regions with strong human activity interference(four sites),moderate human activity interference(five sites)and minor human activity interference(five sites)in Baiyangdian Lake were collected;and their physiological and chemical properties and heavy metals contents were analyzed.The structures of bacterial and fungal communities were tested using 16S ribosomal Ribonucleic Acid(rRNA)and Internal Transcribed Spacer 2(ITS2)high-throughput sequencing technologies.The results indicated that Proteobacteria was the most abundant bacterial phylum.Ascomycota,Basidiomycota and Ciliophora were the dominant phyla of fungi.Obvious differences of microbial genera among the three regions were observed,especially fungal genera.With intensified disturbance by human activities,the Simpson and Shannon indices of bacteria significantly decreased.The fungal communities were clustered into three groups in accordance with the different human disturbance levels.The bacterial communities of sediment samples under moderate and minor human disturbance appeared similar,but different from those under strong human disturbance.Redundancy analysis indicated that zinc,total phosphorus,copper,and lead were the dominant factors that influenced the bacterial community.Nitrifiers and sulfate-reducing bacteria were influenced by pH,nitrate(NO3 ),and total nitrogen.The fungal community was significantly affected by total phosphorus.This study reveals that sediment microbial community structures among different regions of a shallow lake are mainly impacted by human activities.Wenjun Wang Yujun Yi Yufeng Yang Yang Zhou Shanghong Zhang Xuan Wang Zhifeng Yang 2020International Journal of Sediment Research2020,35,2:14
10Seasonal variations in the occurrence and distribution of estrogens and pharmaceuticals in the Zhangweinanyun River System显示文摘The report describes the use of solid-phase extraction(SPE)and LC/MS/MS to investigate the occurrence and distribution of 4 estrogens(estrone,17 β-estradiol,estriol,and 17 α-ethynylestradiol)and 3 anti-inflammatories(ibuprofen,ketoprofen and naproxen)in the Zhangweinanyun River System(China).Relatively higher concentrations were observed for estrone,17 α-ethynylestradiol,and ketoprofen in the Wei Canal than in the Wei River and in the Zhangweixin River.The study suggested that there is a potential ecological risk of male fish feminization from estrogens in the Zhangweinanyun River System.CAO JinLing SHI JiangHong HAN Rui LI YingXia YANG ZhiFeng 2010Chinese Science Bulletin2010,55,27:13
11Water regime-nitrogen fertilizer incorporation interaction:Field study on methane and nitrous oxide emissions from a rice agroecosystem in Harbin, China显示文摘Water regime and nitrogen(N) fertilizer are two important factors impacting greenhouse gases(GHG) emission from paddy field, whereas their effects have not been well studied in cold region. In this study, we conducted a two-year field experiment to study the impacts of water regime and N fertilizer on rice yields and GHG emissions in Harbin, China, a cold region located in high latitudes. Our results showed that intermittent irrigation significantly decreased methane(CH_4) emission compared with continuous flooding, however,the decrement was far lower than the global average level. The N_2O emissions were very small when flooded but peaked at the beginning of the disappearance of floodwater. The N fertilizer treatments increased CH_4 emissions at low level(75 kg N/ha). But both CH_4 and N_2O emissions were uninfluenced at the levels of 150 kg N/ha and 225 kg N/ha. Rice yields increased under intermittent irrigation and were highest at the level of 150 kg N/ha. From our results, we recommended that the intermittent irrigation and 150 kg N/ha as the ideal water regime-nitrogen fertilizer incorporation for this area to achieve low GHG emissions without impacting rice yields.Wenjun Dong Jia Guo Lijun Xu Zhifeng Song Jun Zhang Ao Tang Xijuan Zhang Chunxu Leng Youhong Liu Lianmin Wang Lizhi Wang Yang Yu Zhongliang Yang Yilei Yu Ying Meng Yongcai Lai 2018Journal of Environmental Sciences2018,30,2:12
12Cytocompatibility with osteogenic cells and enhanced in vivo anti-infection potential of quaternized chitosan-loaded titania nanotubes显示文摘Infection is one of the major causes of failure of orthopedic implants. Our previous study demonstrated that nanotube modification of the implant surface, together with nanotubes loaded with quaternized chitosan(hydroxypropyltrimethyl ammonium chloride chitosan, HACC), could effectively inhibit bacterial adherence and biofilm formation in vitro. Therefore, the aim of this study was to further investigate the in vitro cytocompatibility with osteogenic cells and the in vivo anti-infection activity of titanium implants with HACC-loaded nanotubes(NT-H). The titanium implant(Ti), nanotubes without polymer loading(NT), and nanotubes loaded with chitosan(NT-C) were fabricated and served as controls. Firstly, we evaluated the cytocompatibility of these specimens with human bone marrow-derived mesenchymal stem cells in vitro.The observation of cell attachment, proliferation, spreading, and viability in vitro showed that NT-H has improved osteogenic activity compared with Ti and NT-C. A prophylaxis rat model with implantation in the femoral medullary cavity and inoculation with methicillin-resistant Staphylococcus aureus was established and evaluated by radiographical, microbiological, and histopathological assessments. Our in vivo study demonstrated that NT-H coatings exhibited significant anti-infection capability compared with the Ti and NT-C groups. In conclusion, HACC-loaded nanotubes fabricated on a titanium substrate show good compatibility with osteogenic cells and enhanced anti-infection ability in vivo, providing a good foundation for clinical application to combat orthopedic implant-associated infections.Ying Yang Haiyong Ao Yugang Wang Wentao Lin Shengbing Yang Shuhong Zhang Zhifeng Yu Tingting Tang 2016Bone Research2016,4,3:9
13The role of sediment resuspension duration in releaseof PAHs显示文摘Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants. Due to their low water solubility and high hydrophobicity, PAHs are rapidly sorbed onto particles and subsequently deposit in sediments once introduced into aquatic environment. In such a way, sediments become a huge sink for PAHs. During sediment resuspension, the potential exists for PAHs to be released from sediments into water. Sediment resuspension plays an important role in the transportation and fate of PAHs in the aquatic environment. In this study, release behavior of PAHs on Yangtze River sediment during resuspension was investigated using a particle entrainment simulator (PES). The role of re- suspension duration on release of 16 PAHs was measured by resuspending sediment for 12 h at 0.2 and 0.5 N/m2, respectively. Results indicated that PAH concentrations in TSS increase over time with more increase of phenanthrene and 4-ring PAHs. Comparing with 0.2 N/m2 (30%), ∑PAHs concentra- tions in TSS demonstrated remarkable increase during 0.5 N/m2 resuspension (37%). Dissolved PAH concentrations increased throughout the duration with more increase of 2―3 ring PAHs (50%―88%). Dissolved PAH concentrations showed remarkable increase during 0.5 N/m2 resuspension (50%). Moreover, PAH concentrations in overlying water throughout the duration of resuspension were higher than toxic effects threshold values in drinking water developed by WHO, which may cause toxic effect on ecosystem.FENG JingLan SHEN ZhenYao NIU JunFeng YANG ZhiFeng 2008Chinese Science Bulletin2008,53,18:9
14Growth and nutrient accumulation of Phragmites australis in relation to water level variation and nutrient loadings in a shallow lake显示文摘Shallow lake eutrophication is a global environmental issue. This study investigated the effects of water level variation and nutrient loadings on the growth and nutrient accumulation of Phragmites australis (reed) by field samplings in Baiyangdian Lake, the largest shallow lake of northern China. The field samplings were conducted in two sites of different nutrient loadings during the whole growth period of reeds, and three types of zones with different water depths were chosen for each site, including the terrestrial zone with water level below the ground, the ecotone zone with the water level varying from belowground to aboveground, and the submerged zone with water level above the ground. The result showed that reed growth was more limited by water level variation than nutrient loadings. The average stem lengths and diameters in terrestrial zones were about 26.3%-27.5% and 7.2%-12.0% higher than those in submerged zones, respectively. Similarly, the terrestrial status increased the aboveground biomass of reeds by 36.6%-51.8% compared with the submerged status. Both the nutrient concentrations and storages in the aboveground reeds were mainly influenced by the nutrient loadings in surface water and sediment rather than the water level variation of the reed growth environment, and the nutrient storages reached their maxima in late August or early September. It was observed that the maximum nitrogen storage occurred in the terrestrial zone with higher nutrient loadings, with the value of 74.5 g/m 2 . This study suggested that water level variation and nutrient loadings should be considered when using reeds to control and remediate eutrophication of shallow lakes.Ying Zhao Xinghui Xia Zhifeng Yang 2013Journal of Environmental Sciences2013,25,1:9
15Eco-environmental water requirement for wetlands in Huang-Huai-Hai Area, China显示文摘Based on the related literature and the analysis of the relationship between wetland ecosystem and hydroperiod, the estimating and classifying methods of eco-environmental water requirement for wetlands are established. The data collected from Huang-Huai-Hai Area are from the electronic map (1∶250000) of China National Topographical Database of 1997 and the historical statistics since the 1980s.The results indicate that the minimum eco-environmental water requirement for wetlands is 16.98×109 m3 and the optimal one is 38.38×109 m3 in the studied area. For the five wetland nature reserves covered in the area, the values are 1.47×109 m3 and 3.31×109 m3 respectively. The comparisons of the mentioned minimum water requirement with the status water use, which is 17.05×109 m3 for wetland ecosystem (1997 as the status year), suggest that the water use has not met the minimum eco-environmental water requirement in the Haihe and Huanghe Basins of the studied area. However, the status water use guarantees and exceeds the minimum eco-environmental water requirement in the Shandong Peninsula and the Huaihe Basin. Based on the eco-environmental programming and water resource planning of the studied area, the study establishes the water requirement of the year of 2010, 2030, 2050, when the eco-environmental water requirement for wetlands is 18.30×109 m3, 21.64×109 m3 and 26.76×109 m3, respectively.GUI Baoshan and YANG Zhifeng(1. Institute of Environmental Sciences, Beijing Normal University State Key Joint Laboratory of Environmental Simulation and Pollution Control, Beijing 100875, China 2. Institute of Water Sciences, Beijing Normal University Key Laboratory for Water and Sediment Sciences, Ministry of Education, Beijing 100875, China) 2002Progress in Natural Science:Materials International2002,12,11:8
16Is urban development an urban river killer? A case study of Yongding Diversion Channel in Beijing, China显示文摘The high population and concrete environment alter urban areas by changing temperature, rainfall runoff, and water resource utilization activities. This study was conducted to investigate the water quality features of the Yongding Diversion Channel in Beijing, China, and its relationship with rainfall and urban development. Monthly water quality data were obtained from April to October of 2004 at monitoring sites of Sanjiadian, Gaojing, Luodaozhuang, and Yuyuangtan. The monthly water quality grades from 2007 to 2011 were also investigated and compared with those of other rivers. Dissolved oxygen and pH showed greater decreases after one or two moderate rainfall events than several light rainfall events. The potassium permanganate index(CODMn), ammonia nitrogen(NH3-N) and total phosphorus(TP) increased more after several light rainfall events than after one or two moderate or heavy rainfall events. Pollutant concentrations(CODMn, NH3-N, TP) in downstream regions showed greater changes than those in upstream areas after heavy rainfall events. Intense human activities around the channel greatly influenced the water quality of the channel in rainy season because of runoff pollution; however, heavy rainfall had a strong dilution effect on the pollutant concentrations in rivers. Overall, urban development has obviously deteriorated the water quality of the Yongding Diversion Channel as indicated by an increase in the water quality index from 3.22 in 2008 to 4.55 in2010. The Pearson correlation between monthly rainfall and water quality indices from 2007 to 2011ranged from 0.1286 to 0.6968, generally becoming weaker as rainfall and rainfall runoff became more random and extreme.Xi Wang Junqi Li Yingxia Li Zhenyao Shen Xuan Wang Zhifeng Yang Inchio Lou 2014Journal of Environmental Sciences2014,26,6:8
17Turnover and loss of nitrogenous compounds during composting of food wastes显示文摘Few people have so far explored into the research of the dynamics of various nitrogenous compounds(including water-soluble nitrogen)in composting of food wastes.This study aimed to investigate the solid-phase nitrogen,water-soluble nitrogen,nitrogen loss together with ammonia volatilization in the process of food wastes composting.A laboratory scale static aerobic reactor in the experiment was employed in the composting process of a synthetic food waste,in which sawdust was used as the litter amendment.In the experiment,oxygen was supplied by continuous forced ventilation for 15 days.The results have shown that the concentrations of total nitrogen and organic nitrogen decrease significantly in the composting process,whereasNH_(4)^(+)-N concentration increases together with little fluctuation in NO_(3)^(-)-N.After composting,the total content of the water-soluble nitrogen compounds in the compost greatly increased,the total nitrogen loss amounted to 50% of the initial nitrogen,mainly attributed to ammonia volatilization.56.7% of the total ammonia volatilization occurred in the middle and late composting of the thermophilic stage.This suggested that the control at the middle and late composting of thermophilic stage is the key to nitrogen loss in the food waste compost.Yanmei YANG Xiangfeng ZHANG Zhifeng YANG Beidou XI Hongliang LIU 2008Frontiers of Environmental Science & Engineering2008,2,2:8
18The U-Pb chronologic evidence and sedimentary responses of Silurian tectonic activities at northeastern margin of Tarim Basin显示文摘U-Pb ages of Devonian detrital zircons from Tabei Uplift have been determined through LA-ICP-MS test technology.The results revealed that most zircon ages concentrate on 460-414 Ma,especially around 436-423 Ma,indicating possible occurrences of strong tectonic events at the northern margin of Tarim Basin during that period.Combined with previous researches on the basin marginal orogenic belts,intense tectonic activities developed at the northeast margin of Tarim Basin and its obvious sedimentary responses in basin during the end of Ordovician to Early-Middle Silurian are discussed.These include(1) several unconformities within the Late Ordovician-Silurian,showing truncation,erosion,and onlap characteristics,which reflected the local uplift formed during the surrounding extrusion process;(2) the Silurian fluvial delta system from northeast to southwest in Keping,Yingmaili,Hade,and Caohu areas,which reflected the partial uplift at the northeast margin and provided clastic supply to basin;and(3) as indicated by heavy mineral analysis,the Silurian sediments came mainly from the recycles of orogenic belts provenance,which indicated the compress tectonic setting.In addition,a wide range of red mudstone layer distribution in the upper part of the Silurian may be closely related to the surrounding tectonic uplift and the rapid decline of sea levels.LIU JingYan YANG HaiJun YANG YongHeng CAI ZhenZhong LIU YongQuan RUI ZhiFeng SU ZhenZhen 2012Science China Earth Sciences2012,55,9:7
19Serum zinc levels and multiple health outcomes: Implications for zinc-based biomaterials显示文摘Background:Zinc-based biomaterials,including biodegradable metal,nanoparticles,and coatings used in medical implants release zinc ions that may increase the whole-body and serum zinc concentrations.The impact of serum zinc concentrations on major health outcomes can provide insights for device design and clinical transformation of zinc-based biomaterials.Methods:This nationally representative cross-sectional study enrolled participants from the National Health and Nutrition Examination Survey(NHANES,2011-2014)including 3607 participants.Using unadjusted and multivariate-adjusted logistic regression analyses,two-piecewise linear regression model with a smoothing function and threshold level analysis,we evaluated the associations between elevated serum zinc levels and major health outcomes.Results:Elevated serum zinc levels were significantly associated with an increase in total spine and total femur bone mineral density(BMD).Every 10μg/dL increase was associated with a 1.12-fold increase in diabetes mellitus(DM)and 1.23-fold and 1.29-fold increase in cardiovascular diseases(CVD)and coronary heart disease(CHD),in participants with serum zinc levels≥100μg/dL.It had no significant linear or nonlinear associations with risk of fractures,congestive heart failure,heart attack,thyroid disease,arthritis,osteoarthritis,rheumatoid arthritis,dyslipidemia and cancer.Conclusion:Serum zinc levels are significantly associated with increased BMD in the total spine and total femur,and risk of DM,and CVD/CHD among participants with serum zinc levels≥100μg/dL.Xinhua Qu Hongtao Yang Zhifeng Yu Bo Jia Han Qiao Yufeng Zheng Kerong Dai 2020Bioactive Materials2020,5,2:7
20Change of BMD after Weaning or Resumption of Menstruation in Chinese Women with Different FokI VDR-genotypes:A Randomized,Placebo-controlled,Calcium Supplementation Trial显示文摘Objective To investigate the effect of calcium supplementation on bone mineral density (BMD) in Chinese women with different FokI vitamin D receptor (VDR) genotypes (FF,Ff,and ff) after weaning or resumption of menstruation during lactation.Methods A total of 40 subjects with the same FokI VDR genotype were randomly divided into two groups:one received calcium tablet (600 mg once daily as CaCO 3) and the other placebo tablet once daily for 1 year.At baseline,BMD was measured by dual‐energy X‐ray absorptiometry at lumbar spine (L2‐L4) and at left hip whereas serum PICP,serum OC,and urinary CTX,serum 25(OH)VitD 3,and serum estradiol were measured at weaning and 1 year thereafter.Results After the intervention,BMD at lumbar spine and at left hip increased significantly in all these women with a trend among different FokI VDR genotypes such as FF > Ff > ff (P<0.05,<0.01,and <0.001,respectively).BMD at lumbar spine in women with FF VDR genotype increased much more rapidly than in those with ff VDR genotype (P<0.05).Compared with the control group women with the FF genotype regained more BMD after calcium supplementation (P<0.05).Conclusion Daily calcium 600 mg supplementation has beneficial effect on the bone health of women with FF VDR genotype.YU Bo WU HongYing LI Fang GONG Jie ZHOU DunJin ZHANG ZhiFeng YANG XiaoGuang HUANG ZhenWu 2011Biomedical and Environmental Sciences2011,24,3:6
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