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Phosphorus speciation and colloidal phosphorus responses to short-term cessation of fertilization in a lime concretion black soil

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Pedosphere 2023年第6期33卷 948-959页

作者： shanshan bai Jinfang TAN Zeyuan ZHANG Mi WEI Huimin ZHANG Xiaoqian JIANG School of Agriculture Sun Yat-sen UniversityGuangzhou 510275China Shenzhen Campus of Sun Yat-sen University Shenzhen 518107China Modern Agricultural Innovation Center Henan Institute of Sun Yat-sen UniversityZhumadian 463400China Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences/National Engineering Laboratory for Improving Quality of Arable LandBeijing 100081China

Long-term excessive application of mineral fertilizer has led to soil acidification and phosphorus(P) accumulation, increasing the risk of P loss and environmental pollution, and cessation of fertilization is widely considered as a cost-effective management strategy to relieve this situation;however, how such cessation influences P speciation and concentrations in a bulk soil and colloidal fractions and whether decreasing P concentration might maintain soil fertility remain unclear. In this study, the effects of long-term fertilization(ca. 40 years) and short-term cessation of fertilization(ca. 16 months) on inorganic, organic,and colloidal P in lime concretion black soil were investigated using P sequential fractionation and31P nuclear magnetic resonance spectroscopy. After long-term fertilization, available P, dicalcium phosphate, iron-bound P, orthophosphate monoesters, and orthophosphate diesters increased significantly, but soil p H decreased by ca. 2.8 units, indicating that long-term fertilization caused soil acidification and P accumulation and changed P speciation markedly. In contrast, short-term fertilization cessation increased soil p H by ca. 0.8 units and slightly reduced available and inorganic P. Available P after fertilization cessation was 22.9–29.8 mg kg-1, which was still sufficient to satisfy crop growth requirements. Additionally, fertilization cessation increased the proportions of fine colloids(100–450 nm, including nontronite and some amorphous iron oxides) and drove a significant release of iron/aluminum oxide nanoparticles(1–100 nm) and associated P with orthophosphate and pyrophosphate species. In summary, short-term fertilization cessation effectively alleviated soil acidification and inorganic P accumulation, while concomitantly maintaining soil P fertility and improving the potential mobilization of P associated with microparticles.

关键词： Fe/Al oxide nanoparticles fine colloids P accumulation 31pP nuclear magnetic resonance P sequential fractionation soil acidification

Mechanistic insights to sorptive removal of four sulfonamide antibiotics from water using magnetite-functionalized biochar

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Biochar 2023年第1期5卷 1377-1388页

作者： shanshan bai Yaolu Zhou Mingrong Qian Jun Xia Zhiqiang Sun Yujiao Wang Xiaochen Huang Shishu Zhu Key Laboratory of Pollution Exposure and Health Intervention of Zhejiang Province Interdisciplinary Research AcademyZhejiang Shuren UniversityHangzhou 310015People’s Republic of China State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090People’s Republic of China State Key Lab of Biocontrol Guangdong Provincial Key Laboratory of Plant ResourcesSchool of AgricultureShenzhen Campus of Sun Yat-Sen UniversityShenzhen 518107People’s Republic of China The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of EducationSchool of Environment and EnergySouth China University of TechnologyGuangzhou 510006People’s Republic of China

Magnetite-functionalized biochar(MBC)is a promising engineered material for remediation of antibiotic-contaminated ***,sorption mechanisms of ionizable organic compounds such as sulfonamide antibiotics(SAs)on MBC are still *** study employed four representative SAs including sulfamethazine(SMT),sulfamerazine(SMR),sulfadiazine(SDZ),and sulfamethoxazole(SMX),to compare the difference in sorption on *** showed that the sorption capacities and affinities of the four SAs varied with their substituents,hydrophobic properties,and dissociation constants(pKa).Synergistic effect during co-pyrolysis with Fe^(3+)enhanced the sorption performance of MBC towards SAs compared to original *** methods confirmed structural changes of MBC such as the variance in oxygen-containing groups and defective/graphitized *** of modeling pH-dependent sorption revealed that H-bonding orπ-bond assisted H-bonding determined the sorption affinities and capacities of *** particular,the SAs with lower pKa were thermodynamically favorable to form H-bonding with MBC via proton exchange with water *** calculation results quantified the contributions of H-bonding strengths and found that the energies of H-bonding were correlated with affinities of ***,contributions of oxygencontaining groups instead of minerals dominated the H-bonding *** insights from this study can be valuable in exploring engineered BC composites for practical application in field remediation.

关键词： Biochar Antibiotics Sorption capacity Synergistic effect Quantum calculation

The PI3K/AKT Pathway and Renal Cell Carcinoma

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Journal of Genetics and Genomics 2015年第7期42卷 343-353页

作者： Huifang Guo Peter German shanshan bai Sean Barnes Wei Guo Xiangjie Qi Hongxiang Lou Jiyong Liang Eric Jonasch Gordon B.Mills Zhiyong Ding Department of Systems Biology The University of Texas MD Anderson Cancer Center Department of Genitourinary Medical Oncology The University of Texas MD Anderson Cancer Center Department of Radiation Oncology People's Hospital of Linzi District Department of Natural Products Chemistry Key Laboratory of Chemical Biology of Ministry of EducationSchool of Pharmaceutical SciencesShandong University

The phosphatidylinositol 3 kinase （PI3K）/AKT pathway is genetically targeted in more pathway components and in more tumor types than any other growth factor signaling pathway, and thus is frequently activated as a cancer driver. More importantly, the PI3K/AKT pathway is composed of multiple bifurcating and converging kinase cascades, providing many potential targets for cancer therapy. Renal cell carcinoma （RCC） is a high-risk and high-mortality cancer that is notoriously resistant to traditional chemotherapies or radiotherapies. The PI3K/AKT pathway is modestly mutated but highly activated in RCC, representing a promising drug target. Indeed, PI3K pathway inhibitors of the rapalog family are approved for use in RCC. Recent large-scale integrated analyses of a large number of patients have provided a molecular basis for RCC, reiterating the critical role of the PI3K/AKT pathway in this cancer. In this review, we summarize the genetic alterations of the PI3K/AKT pathway in RCC as indicated in the latest large-scale genome sequencing data, as well as treatments for RCC that target the aberrant activated PI3K/AKT pathway.

关键词： PI3K AKT mTOR Renal cell carcinoma Targeted therapy

非负Tucker分解的随机方差缩减乘性更新算法

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南京理工大学学报 2021年第2期45卷 197-204页

作者：白姗姗史加荣西安建筑科技大学理学院陕西西安710055

为了降低乘性迭代算法在求解非负Tucker分解时的计算复杂度,该文在乘性迭代的基础上,提出了一种随机方差缩减乘性更新方法。该方法先将待分解的非负张量n-模式矩阵化,再运用随机方差缩减乘性更新算法对矩阵进行非负分解,得到模式矩阵,... 详细信息

为了降低乘性迭代算法在求解非负Tucker分解时的计算复杂度,该文在乘性迭代的基础上,提出了一种随机方差缩减乘性更新方法。该方法先将待分解的非负张量n-模式矩阵化,再运用随机方差缩减乘性更新算法对矩阵进行非负分解,得到模式矩阵,最后通过梯度下降思想来更新核心张量。对高维数据进行非负Tucker分解时,加快收敛速度且降低计算复杂度,提高了张量分解性能。在人工合成数据集及真实数据集上进行数值实验,结果验证了所提算法的可行性和有效性。

关键词：非负Tucker分解随机方差缩减梯度算法乘性更新梯度下降

O-alg-THAM/gel hydrogels functionalized with engineered microspheres based on mesenchymal stem cell secretion recruit endogenous stem cells for cartilage repair

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Bioactive Materials 2023年第10期28卷 255-272页

作者： Yucong Li Linlong Li Ming Wang Boguang Yang Baozhen Huang shanshan bai Xiaoting Zhang Nan Hou Haixing Wang Zhengmeng Yang Chong Tang Ye Li Wayne Yuk-Wai Lee Lu Feng Micky D.Tortorella Gang Li Stem Cells and Regenerative Medicine Laboratory Li Ka Shing Institute of Health SciencesThe Chinese University of Hong KongPrince of Wales HospitalShatinHong Kong Special Administrative Region of China Musculoskeletal Research Laboratory Department of Orthopaedics&TraumatologyFaculty of MedicineThe Chinese University of Hong KongPrince of Wales HospitalShatinHong Kong Special Administrative Region of China The CUHK-ACC Space Medicine Centre on Health Maintenance of Musculoskeletal System The Chinese University of Hong Kong Shenzhen Research InstituteShenzhenPR China Department of Orthopaedics Peking University Shougang HospitalBeijingPR China Department of Rehabilitation Sciences Hong Kong Polytechnic UniversityHong Kong Special Administrative Region of China Guangzhou Institutes of Biomedicine and Health Chinese Academy of SciencesGuangzhouChina

Lacking self-repair abilities,injuries to articular cartilage can lead to cartilage degeneration and ultimately result in *** engineering based on functional bioactive scaffolds are emerging as promising approaches for articular cartilage regeneration and *** the use of cell-laden scaffolds prior to implantation can regenerate and repair cartilage lesions to some extent,these approaches are still restricted by limited cell sources,excessive costs,risks of disease transmission and complex manufacturing *** approaches through the recruitment of endogenous cells offer great promise for in situ articular cartilage *** this study,we propose an endogenous stem cell recruitment strategy for cartilage *** on an injectable,adhesive and self-healable o-alg-THAM/gel hydrogel system as scaffolds and a biophysio-enhanced bioactive microspheres engineered based on hBMSCs secretion during chondrogenic differentiation as bioactive supplement,the as proposed functional material effectively and specifically recruit endogenous stem cells for cartilage repair,providing new insights into in situ articular cartilage regeneration.

关键词： Bioactive hydrogels Solidified secretome Adhesive hydrogels Acellular functional scaffold Cartilage repair

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基于随机方差调整梯度的非负矩阵分解

吉林大学学报（理学版） 2021年第1期59卷 128-135页

作者：史加荣白姗姗西安建筑科技大学理学院西安710055

针对求解非负矩阵分解的乘性更新规则存在计算复杂度高且迭代效率低等缺点,提出一种随机方差参数调整梯度的方法.将方差缩减策略和乘性更新规则相结合,通过引入一个调整随机梯度估计量的参数校正梯度下降方向使其偏差与方差达到平衡,从... 详细信息

针对求解非负矩阵分解的乘性更新规则存在计算复杂度高且迭代效率低等缺点,提出一种随机方差参数调整梯度的方法.将方差缩减策略和乘性更新规则相结合,通过引入一个调整随机梯度估计量的参数校正梯度下降方向使其偏差与方差达到平衡,从而能快速、准确地逼近最优解.在真实数据集上进行仿真实验,结果验证了该算法的可行性和有效性.

关键词：非负矩阵分解随机梯度下降参数调整梯度方差缩减乘性更新

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一种优化的频率驾驭算法研究

电子与信息学报 2021年第5期43卷 1457-1464页

作者：赵书红董绍武白杉杉高喆中国科学院国家授时中心西安710600 中国科学院时间频率基准重点实验室西安710600 中国科学院大学北京100049 中国科学院大学天文与空间科学学院北京100049

为满足各应用领域对高精度时间性能不断提升的需求,该文设计实现了一种迭代的优化频率驾驭算法,主要分为纸面时间计算和实际物理信号实现两个部分。其中纸面时间计算采用ALGOS算法,利用实时原子钟数据和Circular T公报数据计算获得准确... 详细信息

为满足各应用领域对高精度时间性能不断提升的需求,该文设计实现了一种迭代的优化频率驾驭算法,主要分为纸面时间计算和实际物理信号实现两个部分。其中纸面时间计算采用ALGOS算法,利用实时原子钟数据和Circular T公报数据计算获得准确可靠的时间尺度,保障了驾驭参考的准确性和实时性。实时物理信号实现采用最优二次型高斯控制算法与Kalman算法综合,通过实时调整参数,计算出最优的频率驾驭量,将该驾驭量输送至频率调整设备,最终实现高精度时间信号的输出,整个驾驭系统是闭环的。该文基于我国时间基准保持系统和原子钟组,搭建试验平台,采用该算法对一台氢钟进行为期140天的频率驾驭,最终对输出的物理信号进行性能评估。试验结果表明,该算法有效提高了驾驭后物理信号的准确度和稳定度,驾驭后信号与国际标准时间协调世界时(UTC)相比,相位偏差保持在±3 ns以内,且30天稳定度优于5×10^(–16)。

关键词：高精度时间时间尺度时间保持频率驾驭 Kalman算法最优二次型高斯控制算法

华北平原滴灌施肥灌溉对冬小麦生长和耗水的影响

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农业机械学报 2018年第2期49卷 269-276页

作者：白珊珊万书勤康跃虎中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室北京100101 中国科学院大学资源与环境学院北京100049

针对华北平原地区冬小麦水肥利用效率低且造成一定的面源污染问题,研究了滴灌施肥灌溉对冬小麦生长、产量及其构成要素、耗水量、水分利用效率、灌溉水利用效率和土壤养分分布的影响。结果表明:滴灌施肥灌溉条件下,2013—2014、2014—2... 详细信息

针对华北平原地区冬小麦水肥利用效率低且造成一定的面源污染问题,研究了滴灌施肥灌溉对冬小麦生长、产量及其构成要素、耗水量、水分利用效率、灌溉水利用效率和土壤养分分布的影响。结果表明:滴灌施肥灌溉条件下,2013—2014、2014—2015和2015—2016年冬小麦平均产量为7 120.5 kg/hm2,相比当地产量(6 000 kg/hm2)提高了18.7%,冬小麦穗粒数和千粒质量表现较好,千粒质量平均提高了4.3 g。2013—2014、2014—2015和2015—2016年冬小麦全生育期耗水量平均为387.9 mm。播种期-拔节期降水量占阶段耗水量的比例最大(52%),拔节期-抽穗期灌水量所占比例最大(78%),而抽穗期-收获期土壤储水量的消耗量所占比例最大(54%)。3年度冬小麦全生育期耗水量各组成所占比例表现为:灌水量所占比例最大,为49%,其次是土体储水量的消耗量,占总耗水量的25%,降水量占总耗水量的24%,地下水补给量占总耗水量的比例最小,仅2%。冬小麦水分利用效率和灌溉水利用效率分别为1.8、3.9 kg/m3,相比地面灌溉分别提高了38%、95%。养分主要分布在根区0~40 cm土层内,养分利用率高,养分淋失少。因此,华北平原地区控失肥作为底肥,采用滴灌施肥灌溉进行随水追肥,当施肥量为当地施肥量的70%时,可提高冬小麦产量18.7%,穗粒数和千粒质量表现较好。此外,滴灌施肥灌溉可节水36%,节肥30%,提高灌溉水利用效率95%,提高水分利用效率38%。

关键词：冬小麦滴灌施肥灌溉耗水量水分利用效率

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政府在基层图书馆建设中的角色与责任

图书与情报 2010年第4期 59-61,117页

作者：白珊珊刘兹恒北京大学信息管理系北京100871

文章首先明确了政府在基层图书馆建设中的责任主体地位,并阐述了其具体依据,而后详细论述了政府在基层图书馆建设中应该履行的六个方面的具体责任。

关键词：基层图书馆政府责任