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Response to temperature stress of reactive oxygen species scavenging enzymes in the cross-tolerance of barley seed germination

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第12期11卷 965-972页

作者： Yu-qin mei song-quan song Institute of Botany Chinese Academy of Sciences Beijing 100093 China

A number of studies have shown the existence of cross-tolerance in plants, but the physiological mechanism is poorly understood. In this study, we used the germination of barley seeds as a system to investigate the cross-tolerance of low-temperature pretreatment to high-temperature stress and the possible involvement of reactive oxygen species （ROS） scavenging enzymes in the cross-tolerance. After pretreatment at 0 ℃ for different periods of time, barley seeds were germinated at 35 ℃, and the content of malondialdehyde （MDA） and the activities of ROS scavenging enzymes were measured by a spectrophotometer analysis. The results showed that barley seed germinated very poorly at 35 ℃, and this inhibitive effect could be overcome by pretreatment at 0 ℃. The MDA content varied, depending on the temperature at which seeds germinated, while barley seeds pretreated at 0 ℃ did not change the MDA content. Compared with seeds germinated directly at 35 ℃, the seeds pretreated first at 0 ℃ and then germinated at 35 ℃ had markedly increased activities of superoxide dismutase （SOD）, ascorbate peroxidase （APX）, catalase （CAT）, and glutathione reductase （GR）. The SOD and APX activities of seeds germinated at 35 ℃ after 0 ℃-pretreatment were even substantially higher than those at 25 ℃, and GR activity was similar to that at 25 ℃, at which the highest germination performance of barley seeds was achieved. These results indicate that low-temperature pretreatment can markedly increase the tolerance of barley seed to high temperature during germination, this being related to the increase in ROS scavenging enzyme activity. This may provide a new method for increasing seed germination under stress environments, and may be an excellent model system for the study of cross-tolerance.

关键词： Barley seed Cross-tolerance Germination/growth Reactive oxygen species (ROS) scavenging enzyme,Pretreatment at low temperature Temperature stress

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Gasser-Leutwyler Coefficients of Chiral Lagrangian for Pseudoscalar Goldstone Bosons in Dyson-Schwinger Equations

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Communications in Theoretical Physics 2008年第11期50卷 1205-1210页

作者： GU Yun-Ting qin song-mei ZHOU Li-Juan MA Wei-Xing Department of Physics Guangxi University Nanning 530004 China Collaboration Group of Hadron Physics and Non-perturbative QCD Study Guangxi University of Technology Liuzhou 545006 China Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

Based on the Dyson-Schwinger equations of quark propagator in rainbow truncation with an effective gluonpropagator,the ten unknown Gasser-Leutwyler coefficients of the chiral Lagrangian for pseudoscalar Goldstone bosonsare *** predicted values of L_i with i=1,2,...,10 are in a reasonable agreement with empirical values usedwidely in literature,and the values predicted by many other theoretical models with QCD characteristics.

关键词： chiral perturbation theory Gasser-Leutwyler coefficient Dyson-Schwinger equation

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Clinical Analysis of 13 Cases with Burkitt Lymphoma or Burkittlike Lymphoma

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Clinical oncology and cancer researeh 2010年第2期7卷 110-115页

作者： Ning-jing LIN Wen ZHENG Yun-tao ZHANG Xiao-pei WANG Yu-qin song Yan XIE mei-feng TU Ling-yan PING Jun ZHU Department of Lymphoma Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) Peking University School of Oncology Beijing Cancer Hospital and Institute Beijing 100142 China.

OBJECTIVE To summarize the clinical characteristics and treatment effects of Burkitt lymphoma （BL） and Burkitt-like lymphoma （BLL）, and to explore the best possible optimal regimens and the treatment-related *** Clinical data of 13 BL and BLL patients, who were pathologically diagnosed and treated in the Beijing Cancer Hospital from August 1996 to October 2008, were retrospectively analyzed, All patients received the therapeutic regimen with chemotherapy as the first-line treatment. The treatment effect and adverse reactions were *** Of the 13 patients, 12 were men and 1 was woman, with a median age of 15 years （range, 11-62）. Three of the patients were in stage Ⅰ, 2 in stage Ⅱ, 2 in stage Ⅲ, and 6 in stage Ⅳ. Advanced cases were 8 （stage Ⅲ and Ⅳ）, accounting for 61.5% of the patients. Bone marrow involvement was found in 2 cases （15.4%） and central nervous system invasion in 4 （30.8%） at the beginning of the treatment. The common involved sites included the superficial lymph nodes （61.5%）, abdominal organs （53.8%）, and abdominal and retro-peritoneal lymph nodes （38.5%）. B symptoms were observed in 7 patients （53.8%）. Serum lactate dehydrogenase （LDH） level was increased in 8 of the 10 patients who underwent the serum LDH determination, while serum uric acid level was increased in 1 of the 10. Pathological diagnosis showed that 11 of the cases were BL and 2 BLL. Of the 13 patients, 11 （84.6%） achieved a complete remission （CR） or CR/unconfirmed （CRu）, and 1 （7.7%） a partial remission （PR）, with a total responsive rate of 92.3%. At a median follow-up of 8 months （range 5-35）, 6 patients were found dead at the end of the follow-up. One of the 13 patients was lost to the follow-up. The 1-year overall survival, progression-free survival and disease-free survival rates were 56.98%, 32.31% and 39.77%, respectively. The grade-Ⅲ or Ⅳ myelosuppression was found in 9 patients during the chemotherapy （69.2%）, and tumor lysis syndrome and grade-

关键词： Burkitt lymphoma invasion biomedicalresearch drug therapy combination.

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Potential role of tanycyte-derived neurogenesis in Alzheimer's disease

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Neural Regeneration Research 2025年第6期20卷 1599-1612页

作者： Guibo Qi Han Tang Jianian Hu Siying Kang song qin Department of Anatomy Histologyand EmbryologySchool of Basic Medical SciencesFudan UniversityShanghaiChina State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Fudan UniversityShanghaiChina

Tanycytes, specialized ependymal cells located in the hypothalamus, play a crucial role in the generation of new neurons that contribute to the neural circuits responsible for regulating the systemic energy balance. The precise coordination of the gene networks controlling neurogenesis in naive and mature tanycytes is essential for maintaining homeostasis in adulthood. However, our understanding of the molecular mechanisms and signaling pathways that govern the proliferation and differentiation of tanycytes into neurons remains limited. This article aims to review the recent advancements in research into the mechanisms and functions of tanycyte-derived neurogenesis. Studies employing lineage-tracing techniques have revealed that the neurogenesis specifically originating from tanycytes in the hypothalamus has a compensatory role in neuronal loss and helps maintain energy homeostasis during metabolic diseases. Intriguingly,metabolic disorders are considered early biomarkers of Alzheimer's disease. Furthermore,the neurogenic potential of tanycytes and the state of newborn neurons derived from tanycytes heavily depend on the maintenance of mild microenvironments, which may be disrupted in Alzheimer's disease due to the impaired blood–brain barrier ***, the specific alterations and regulatory mechanisms governing tanycyte-derived neurogenesis in Alzheimer's disease remain unclear. Accumulating evidence suggests that tanycyte-derived neurogenesis might be impaired in Alzheimer's disease, exacerbating neurodegeneration. Confirming this hypothesis, however, poses a challenge because of the lack of long-term tracing and nucleus-specific analyses of newborn neurons in the hypothalamus of patients with Alzheimer's disease. Further research into the molecular mechanisms underlying tanycyte-derived neurogenesis holds promise for identifying small molecules capable of restoring tanycyte proliferation in neurodegenerative diseases. This line of investigation could pro

关键词： Alzheimer's disease blood–brain barrier ependymoglial cells hypothalamus metabolic diseases neural stem cells neurogenesis neuroinflammatory diseases neurons tanycyte

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An efficient quantum proactive incremental learning algorithm

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 49-57页

作者： Lingxiao Li Jing Li Yanqi song Sujuan qin Qiaoyan Wen Fei Gao State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications School of Cyberspace Security Beijing University of Posts and Telecommunications

In scenarios where a large amount of data needs to be learned, incremental learning can make full use of old knowledge, significantly reduce the computational cost of the overall learning process, and maintain high performance. In this paper, taking the MaxCut problem as our example, we introduce the idea of incremental learning into quantum computing, and propose a Quantum Proactive Incremental Learning algorithm(QPIL). Instead of a one-off training of quantum circuit, QPIL contains a multi-phase training on gradually-increased subgraphs of all vertices, proactively reducing large-scale problems to smaller ones to solve in steps, providing an efficient solution for MaxCut. Specifically, some vertices and corresponding edges are randomly selected for training to obtain optimized parameters of the quantum circuit at first. Then, in each incremental phase, the remaining vertices and corresponding edges are gradually added and the parameters obtained from the previous phase are reused in the parameter initialization of the current phase. We perform experiments on 120 different small-scale graphs, and it shows that QPIL performs superior to prevalent quantum and classical baselines in terms of approximation ratio(AR), time cost, anti-forgetting, and solving stability. In particular, QPIL's AR surpasses 20% of mainstream quantum baselines, and the time cost is less than 1/5 of them. The idea of QPIL is expected to inspire efficient and high-quality solutions in large-scale Max Cut and other combinatorial optimization problems.

关键词： variational quantum algorithm incremental learning multi-phase training MaxCut quantum computing

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用于VOIP的G.729A算法的优化改进

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电子技术应用 2007年第7期33卷 104-106页

作者：杨召青黄冰宋钦梅桂林电子科技大学信息研究室广西桂林541004

在VOIP应用的基础上,介绍了VOIP的现状及其用于VOIP语音编码标准的发展方向,并对VOIP网路通信语音编码标准之一的G.729 A[1]进行了优化改进,提出了一种利用重新初始化来获得状态恢复(RbR)与WD-LSP[8](Weighted delta-LSP)相结合的CS-AC... 详细信息

在VOIP应用的基础上,介绍了VOIP的现状及其用于VOIP语音编码标准的发展方向,并对VOIP网路通信语音编码标准之一的G.729 A[1]进行了优化改进,提出了一种利用重新初始化来获得状态恢复(RbR)与WD-LSP[8](Weighted delta-LSP)相结合的CS-ACELP语音编码算法,利用重新初始化来获得状态恢复,解决了包丢失阶段和在包丢失以后阶段产生差错脉冲所引起的重建语音质量下降问题的同时,采用WD-LSP降低了算法复杂度。

关键词： G.729A WD—LSP CS—ACELP RbR

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基于G.729A的CS-ACELP语音编码算法的优化改进

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电子技术应用 2007年第3期33卷 114-116页

作者：宋钦梅黄冰杨召青桂林电子科技大学通信与信息工程系广西桂林541004

介绍了G.729A的现状以及在发展过程中其语音编码的改进方向及具体方法。提出了一种结合WD-LSP(Weighted Delta-LSP)并采用次最优部分码本快速搜索的CS-ACELP语音编码算法,同时采用基于声学心理模型的知觉加权滤波器,使语音编码在不降低... 详细信息

介绍了G.729A的现状以及在发展过程中其语音编码的改进方向及具体方法。提出了一种结合WD-LSP(Weighted Delta-LSP)并采用次最优部分码本快速搜索的CS-ACELP语音编码算法,同时采用基于声学心理模型的知觉加权滤波器,使语音编码在不降低语音质量的情况下降低计算复杂度。

关键词： G.729A WD—LSP CS—ACELP 部分码本快速搜索知觉加权滤波器

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伽马射线暴X射线余辉中星风—星际介质转变的行为

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广西大学学报（自然科学版） 2020年第3期45卷 659-666页

作者：秦松梅李龙王祥高广西中医药大学数理教研室广西南宁530001 广西大学物理科学与工程技术学院广西南宁530004 广西大学—国家天文台天体物理和空间科学研究中心广西南宁530004 广西大学广西相对论天体物理重点实验室广西南宁530004

伽马射线暴(GRB)暴周环境是研究伽马暴物理的重要手段。其余辉的斜率“由陡变平”的行为可以用伽马暴暴周环境由星风向星际介质转变来解释,但至今还缺乏系统的样本搜寻。基于外激波模型,对2004年~2018年Swift卫星观测的X射线余辉进行系... 详细信息

伽马射线暴(GRB)暴周环境是研究伽马暴物理的重要手段。其余辉的斜率“由陡变平”的行为可以用伽马暴暴周环境由星风向星际介质转变来解释,但至今还缺乏系统的样本搜寻。基于外激波模型,对2004年~2018年Swift卫星观测的X射线余辉进行系统的搜寻,寻找具有星风—星际介质转变特征的GRB,发现了6个GRB具有星风—星际介质转变的特征。对其进行模型拟合后,得到了一组最佳拟合结果相应的物理参数。结果表明:①星风—星际介质转变时间一般在暴后800~2000 s,转变半径R t在1016~1017 cm,密度跳跃参数在4~10,电子谱指数p在2.1~2.6;②它们的各向同性动能E k,iso在1053~1054 erg,与一般长暴的典型值相比要小一些;③具有星风—星际介质转变的GRBs在喷流张角比较大,大部份大于10°。

关键词：伽马暴暴周环境外激波模型

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伽玛暴光学余辉中的双喷流成份行为

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广西大学学报（自然科学版） 2015年第3期40卷 680-685页

作者：秦松梅邓灿敏王祥高广西大学物理科学与工程技术学院国家天文台广西大学天体物理和空间科学研究中心广西南宁530004 广西中医药大学数理教研室广西南宁530001 广西相对论天体物理重点实验室广西南宁530004

伽玛暴余辉的双拐折行为可以用双喷流成份结构模型得到较好的解释,但至今其物理参数还未解.为给出其相应的物理参数,文中将对具有双喷流成份的伽玛暴光学余辉进行统计分析,用外激波模型时域指数α和频域指数β的关系（closure relation... 详细信息

伽玛暴余辉的双拐折行为可以用双喷流成份结构模型得到较好的解释,但至今其物理参数还未解.为给出其相应的物理参数,文中将对具有双喷流成份的伽玛暴光学余辉进行统计分析,用外激波模型时域指数α和频域指数β的关系（closure relation）对数据进行限制,得到 GRB 071003,GRB 080319B,GRB 090426和GRB 100219A共4个具有外激波模型的伽玛暴双成份喷流特征.这些伽玛暴第一个喷流成份的张角都在1°以内,而第二个喷流成份的张角增大到2°-7°,与单成份喷流的张角一致.其各向同性辐射能量在1051ц1054 erg,电子谱指数p约为2,比典型值2.3硬.长暴能较好符合Amati关系.

关键词：伽玛暴双喷流.外激波模型

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学生伤害事故法律责任述论

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毕节师范高等专科学校学报（综合版） 2005年第2期23卷 71-73页

作者：秦松梅代丽毕节师专政史系贵州毕节551700 遵义十中贵州遵义563000

学生伤害事故是指学生在校期间或在与学校有关的教育活动中发生的人身伤害事故。近些年来,此类事故时有发生,成为教育界、法学界甚至社会各界关注的热点之一,如何认定学校的法律责任,学校承担法律责任的类型和方式等问题成为人们关注的... 详细信息

学生伤害事故是指学生在校期间或在与学校有关的教育活动中发生的人身伤害事故。近些年来,此类事故时有发生,成为教育界、法学界甚至社会各界关注的热点之一,如何认定学校的法律责任,学校承担法律责任的类型和方式等问题成为人们关注的焦点。但是,到目前为止,有关这方面的研究仍处于起步阶段。理论研究的滞后导致实践操作的困难。现实中主要表现为学生伤害事故不能得到正确、及时、有效和公正的处理与解决。基于此,根据我国现行法律的规定,结合学校实际情况,对此进行简要论述。

关键词：学生伤害事故法律责任过错责任原则学校管理中国

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