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南充市昆虫传粉网络及其对主要授粉作物传粉服务价值研究

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昆虫学报 2024年第2期67卷 255-269页

作者：胡丹李秀山常雪梅胥勋露曾桂王琼西华师范大学生命科学学院西南地区野生动植物资源保护教育部重点实验室南充637009

【目的】查明四川省南充市传粉昆虫资源,研究当地植物-昆虫的传粉网络,评估传粉昆虫对该市主要授粉作物的传粉服务价值及其对农业生产的贡献。【方法】2021-2022年采用随机网捕采集、样方调查传粉昆虫资源、构建传粉网络,通过套袋隔离... 详细信息

【目的】查明四川省南充市传粉昆虫资源,研究当地植物-昆虫的传粉网络,评估传粉昆虫对该市主要授粉作物的传粉服务价值及其对农业生产的贡献。【方法】2021-2022年采用随机网捕采集、样方调查传粉昆虫资源、构建传粉网络,通过套袋隔离试验测定作物对昆虫的传粉依存度,并依据2020年南充市相关农林经济数据评估了昆虫的传粉服务价值和经济贡献率。【结果】2021-2022年从南充市共调查到传粉昆虫79种,隶属于18科50属,授粉农作物和野生蜜源植物有59种,隶属于20科50属;传粉网络呈现低连接度、中嵌套度、低等网络特化程度的结构特征;2020年南充市传粉昆虫的传粉服务价值为332 501.76~507 279.12万元,占当年农业生产总值的8.45%~12.88%。【结论】南充市的传粉昆虫资源丰富,为当地的蔬菜、水果和油料作物生产提供了充分的传粉服务;南充市传粉网络的特征明显,传粉昆虫能够维持生态系统稳定和植物物种多样性;主要授粉作物对昆虫传粉的依赖程度高,农业生产与传粉昆虫之间关系紧密,保护传粉昆虫资源有助于保障南充市农业生产,并维持野生植物群落的稳定。

关键词：传粉昆虫传粉网络传粉依存度传粉服务价值

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Search for gamma-ray line signals around the black hole at the galactic center with DAMPe observation

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Science China(Physics,Mechanics & Astronomy) 2022年第6期65卷 150-158页

作者： Tian-Ci Liu Ji-gui Cheng Yun-Feng Liang en-Wei Liang Laboratory for Relativistic Astrophysics Department of PhysicsGuangxi UniversityNanning 530004China

The adiabatic growth of a black hole(BH)may enhance the dark matter(DM)density surrounding it,causing a spike in the DM density *** spike around the supermassive BH at the center of the Milky Way may lead to a dramatic enhancement of the gamma-ray flux of DM annihilation from the galactic center(GC).In this work,we analyze the gamma-ray data of the innermost region(i.e.,the inner 1°)of the GC to search for potential line-like signals from the BH *** line-like signals could be generated in the process of DM particles annihilating into double *** adopt the gamma-ray data from the Dark Matter Particle explorer(DAMPe).Although the DAMPe has a much smaller effective area than the Fermi-LAT,the gamma-ray line search can benefit from its unprecedented high energy *** significant line-like signals are found in our *** derive upper limits on the cross section of the annihilation based on this *** find that despite the DAMPe’s small effective area for photon detection,we can still place strong constraints on the cross section(≥10^(-27)cm^(3)s^(-1))in the spike scenario due to the very bright model-expected flux from the *** results indicate that either DM does not annihilate primarily through theγγchannel in the mass range we considered or no sharp density spike is present at the GC.

关键词： dark matter γ-ray telescopes black holes galactic center

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气候变化下大兴安岭南段季节冻土退化特征

林业科学研究 2024年第3期37卷 86-94页

作者：孙逸晨魏江生舒洋赵鹏武齐桂萍张静内蒙古农业大学草原与资源环境学院内蒙古呼和浩特010011 内蒙古赛罕乌拉森林生态系统国家野外观测研究站内蒙古赤峰025150 内蒙古农业大学林学院内蒙古呼和浩特010019 内蒙古自治区土壤质量与养分资源重点实验室内蒙古呼和浩特010018 农业生态安全与绿色发展自治区高等学校重点实验室内蒙古呼和浩特010018 内蒙古赤峰市青山林场内蒙古赤峰024200 内蒙古赤峰市赛罕乌拉自然保护区管理局内蒙古赤峰025150

[目的]季节冻土退化会直接影响生长季初期的水分补给,进而影响区域森林健康。然而,目前大兴安岭南段的冻土退化,特别是气候变化下冻土如何退化尚不清楚。[方法]在内蒙古赛罕乌拉国家级自然保护区长期实验森林中,定位观测2014-2022年气... 详细信息

[目的]季节冻土退化会直接影响生长季初期的水分补给,进而影响区域森林健康。然而,目前大兴安岭南段的冻土退化,特别是气候变化下冻土如何退化尚不清楚。[方法]在内蒙古赛罕乌拉国家级自然保护区长期实验森林中,定位观测2014-2022年气温、土壤温度、土壤体积含水量等环境因子,分析森林季节冻土退化特征。[结果]研究表明:大兴安岭南段气温加速上升,1997-2022年间年平均气温上升速率为0.42℃·(10 a)^(-1),比1973-1996年间的升温速率[0.34℃·(10 a)^(-1)]加快了23.5%;且冻融期(当年11月-次年6月)平均气温上升速率更快[0.46℃·(10 a)^(-1)]。土壤的冻融模式呈自上而下单向冻结,单向融化;冻结速率、融化速率随着土壤深度的增加而变快,在40~80 cm土层达到最大值(冻结速率2.23 cm·d^(-1)、融化速率4.50 cm·d^(-1))。季节冻土持续退化,观测到的最大冻结深度由80 cm减少至40 cm;冻融期显著缩短,开始冻结时间推迟,完全融化时间提前,导致年冻融期缩短15.21%。应用本文建立的冻融多元线性回归模型计算得出,积温升高对研究区季节冻土退化的贡献率超过90%,是该区域季节冻土退化的最主要原因。[结论]在大兴安岭南段,冻土退化主要表现为冻融期缩短,气温升高是导致季节冻土退化的主要驱动因素,今后有必要监测季节冻土的变化,从而更好地进行森林经营。

关键词：气候变化季节性冻土冻土退化冻融期

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基于Nrf2/HO-1信号通路调控的恰玛古多糖抗多柔比星心肌毒性的机制研究

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药学学报 2024年第4期59卷 930-938页

作者：郭君婷赵婷婷叶斯木·塔拉甫别克高瑞娟刘桂花新疆维吾尔自治区药物研究所新疆乌鲁木齐830000 新疆维吾尔药重点实验室新疆乌鲁木齐830000 中国医学科学院医药生物技术研究所北京100050 新疆医科大学药学院新疆乌鲁木齐830011

本研究主要探讨了恰玛古多糖(polysaccharides of Brassica rapa L.,BRPs)对多柔比星(doxorubicin,DOX)心脏毒性的作用及相关机制,研究选用H9c2细胞作为研究对象,采用Cell counting kit-8(CCK-8)法检测BRPs对DOX致H9c2细胞损伤的影响;将H9c2细胞分成对照组、模型组和药物组(0.5~3 mg·mL^(-1)),对照组于正常条件下培养,其余各组在处理后进行1μmol·L^(-1) DOX诱导24 h。通过流式细胞仪检测各组细胞凋亡;分别测定各组细胞乳酸脱氢酶(lactate dehydrogenase,LDH)、细胞内超氧化物歧化酶(superoxide dismutase,SOD)和丙二醛(malondialdehyde,MDA)的含量;检测细胞内活性氧(ROS)和线粒体膜电位(mitochondrial membrane potential,MMP);Western blot检测凋亡及转录因子NF-e2相关因子(NF-e2-related factor 2,Nrf2)/血红素加氧酶-1(heme oxygenase-1,HO-1)通路相关蛋白表达。与对照组相比,DOX致H9c2细胞损伤的细胞活力下降、凋亡率增加,LDH、MDA水平升高,SOD活性降低,ROS水平显著增多,MMP显著下降;B淋巴细胞瘤-2(B cell lymphoma-2,Bcl-2)蛋白水平降低,Bcl-2关联X蛋白(Bcl associated X protein,Bax)水平显著升高;且模型组Nrf-2、HO-1、醌氧化还原酶1(quinone oxidoreductase 1,NQO1)蛋白表达水平降低,Kelch样环氧氯丙烷相关蛋白1(Kelch-like eCH-associated protein 1,Keap1)和磷酸化p38丝裂原活化蛋白激酶蛋白表达水平显著升高。与模型组相比,BRPs各组在0.5~3 mg·mL^(-1)对DOX致H9c2细胞损伤具有保护作用,降低细胞凋亡及LDH、MDA和细胞内ROS水平,增强SOD活性,升高MMP;同时,BRPs可上调凋亡相关Bcl-2,并下调Bax水平;而且,BRPs可使Nrf2、HO-1、NQO1蛋白表达水平升高,Keap1和磷酸化p38丝裂原活化蛋白激酶水平降低。本研究认为BRPs能够保护H9c2细胞,抑制细胞凋亡,可能与其调节Nrf2/HO-1通路拮抗氧化应激有关。

关键词：恰玛古多糖多柔比星心肌毒性氧化应激 Nrf2/HO-1信号通路

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Middle thyroid vein tumor thrombus in metastatic papillary thyroid microcarcinoma:A case report and review of literature

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World Journal of Clinical Cases 2022年第10期10卷 3213-3221页

作者： Yan gui Jun-Yi Wang Xu-Dong Wei Department of Otorhinolaryngology Head and Neck Surgery The First Hospital of Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Department of Thyroid and Neck Tumor Key Laboratory of Cancer Prevention and Therapy of TianjinTianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerTianjin 300060China Department of Otorhinolaryngology Head and Neck Surgery Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina

BACKGROUND Although papillary thyroid microcarcinoma(PTMC)is not considered a threatening tumor,in some cases,it can be *** thrombosis of papillary thyroid carcinoma,follicular thyroid carcinoma,Hürthle cell carcinoma,poorly differentiated thyroid carcinoma and anaplastic thyroid carcinoma have been reported in the literature,but there have been no reports about *** SUMmarY A 45-year-old woman presented with a thyroid mass and thrombosis in a middle thyroid vein during a physical *** had no symptoms,and the physical examination showed no positive *** ultrasonographyguided fine-needle aspiration biopsy results indicated an atypical lesion of ambiguous significance,with some actively growing cells(TBSRTCⅢ)and the BRAFV600e mutation not *** patient underwent left thyroidectomy,isthmus lobectomy,prophylactic central lymph node dissection and *** pathology showed papillary microcarcinoma of the left thyroid,and the thrombus in the middle thyroid vein was a tumor *** Middle thyroid vein tumor thrombus is an extremely rare condition in PTMC,but it does *** and thromboembolectomy may be an option for patients with thrombi in the middle vein of the thyroid,and we strongly suggest close follow-up of these patients.

关键词： Thyroid neoplasms Papillary carcinoma Thyroid vein Venous thrombosis Surgery Case report

Functional characterization of sex pheromone receptors in Spodoptera frugiperda, S. exigua, and S. litura moths

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Insect Science 2023年第2期30卷 305-320页

作者： Sai Zhang Fang Liu Bin Yang Yang Liu gui-Rong Wang State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBejingChina College of Horticulture and Plant Protection Yangzhou UniversityYangzhouChina Shenzhen Branch Guangdong Laboratory for Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of AgricultureAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhenChina

Moths possess an extremely sensitive and diverse sex pheromone processing system,in which pheromone receptors(PRs)are essential to ensure communication between mating *** properties of some PRs are conserved among species,which is important for ***,functional differentiation has occurred in some homologous PR genes,which may drive species ***,using genome analysis,17 PR genes were identified from Spodoptera frugiperda,***,and ***,which belong to 6 homologous groups(odorant receptor[OR]6,11,13,16,56,and 62);of which 6 PR genes(OR6,OR11,OR13,OR16,OR56,and OR62)were identified in *** and ***,and 5 PR genes were identified in ***,excluding *** heterologous expression in Xenopus oocytes,we characterized the functions of PR orthologs including OR6,OR56,and OR62,which have not been clarified in previous ***6 orthologs were specifically tuned to(Z,e)-9,12-tetradecadienyl acetate(Z9,e12-14:OAc),and OR62 orthologs were robustly tuned to Z7-12:OAc in *** and *** optimal ligand for OR56 was Z7-12:OAc in ***,but responses were minimal in *** and *** addition,SfruOR6 was male antennae-specific,whereas SfruOR56 and SfruOR62 were male *** study further clarified the functional properties of PRs in 3 Spodoptera moth species,providing a comprehensive understanding of the mechanisms of intraspecific communication and interspecific isolation in Spodoptera.

关键词： pheromone pheromone receptor Spodoptera Xenopus oocytes

Developing a high-performance Al–Mg–Si–Sn–Sc alloy for essential room-temperature storage after quenching: aging regime design and micromechanisms

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Rare Metals 2023年第11期42卷 3814-3828页

作者： Shuai Pan Xin-Jian Chen gui-Zhen Liao Asad Ali Shuang-Bao Wang School of Physical Science and Technology&Collaborative Innovation Center of Sustainable energy Materials Guangxi UniversityNanning530004China Key Laboratory of LCR Materials and Devices of Yunnan Province School of Materials and EnergyYunnan UniversityKunming650500China electron Microscopy Center Yunnan UniversityKunming650500China

Sn microalloying can depress the adverse effect of natural aging after quenching(i.e., room-temperature storage) of Al-Mg-Si alloys. However, the other effect of Sc micro-addition to the Al-Mg-Si-Sn alloys remains elusive. Here, the optimal room-temperature storage time,properties and micromechanisms of Al-0.43 Mg-1.2Si-0.1Sn-0.1Sc(wt%) alloy are investigated by atomic-resolution scanning transmission electron microscopy(STeM),microhardness and corrosion resistance tests. The results show that the peak-aging Al-Mg-Si-Sn-Sc alloy exhibits vastly shortened peak hardening time, increased thermal stability and corrosion resistance compared with its Sc-free counterpart after a long room-temperature storage time of 1 week. Under such a designed double-stage aging regime(1-week room-temperature storage + artificial aging at 180℃), the addition of Sc to Al-Mg-Si-Sn alloy induces a decrease in diameter but an increase in length of peakhardening β″-based precipitates. In addition, a suppressed over-aging phase transition from Sc/Sn-containing β″ to β′ is identified in the Al-Mg-Si-Sn-Sc alloy. The Sn tends to segregate to the Si site in the low-density cylinder of β″ and the central site of sub-B′ in the precipitate can be occupied by Sn/Sc. Further study reveals that Sc and Sn coexist in the precursors of β″. Both reduced width of precipitation free zones and protective corrosion product film easily formed on the material contribute to the improved corrosion resistance of Al-Mg-Si-Sn-Sc *** results provide important insight into the development of high-performance Al alloys.

关键词： AlMgSiSn alloys Sc microalloying Aging regime Property Micromechanisms

内生真菌对醉马草不同生长期土壤酶活性和养分的影响

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草地学报 2024年第6期32卷 1770-1778页

作者：刘荣贵邓茂桦张瀚文郑蓉唐仲龙王超王剑峰兰州大学草种创新和草地农业生态系统全国重点实验室/兰州大学草地微生物研究中心/兰州大学草地农业科技学院甘肃兰州730020 临夏州农业科学院甘肃临夏731100

醉马草-内生真菌共生体是研究生态系统中地上与地下生物联系的独特模式,但该共生体对不同生长期土壤酶活性和养分含量的影响知之甚少。本研究采集休眠期和返青期携带内生真菌(e+)和未携带内生真菌(e-)醉马草的生境土壤,测定e+和e-醉马... 详细信息

醉马草-内生真菌共生体是研究生态系统中地上与地下生物联系的独特模式,但该共生体对不同生长期土壤酶活性和养分含量的影响知之甚少。本研究采集休眠期和返青期携带内生真菌(e+)和未携带内生真菌(e-)醉马草的生境土壤,测定e+和e-醉马草土壤酶活性和养分含量。结果表明:在休眠期和返青期,内生真菌显著增加了醉马草土壤速效磷含量,较e-醉马草分别提高34.7%和36.7%。在返青期内生真菌增加了醉马草土壤硝态氮含量,较e-醉马草提高了32.3%。此外,返青期温度升高增强了e+和e-醉马草土壤蔗糖酶和碱性磷酸酶活性,这提高了土壤N、P的有效性,为醉马草的生长返青提供基本养分。以上结果表明内生真菌通过调节土壤养分提高土壤肥力,返青期土壤酶活性和养分含量的变化保证了醉马草顺利返青。本研究为深入理解禾草-内生真菌共生体的生态学作用提供理论依据。

关键词：醉马草内生真菌土壤酶活性和养分含量休眠期和返青期

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基于RF的并行CNN-TGLSTM热负荷预测模型

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华北理工大学学报（自然科学版） 2024年第2期46卷 112-123页

作者：谭全伟薛贵军谢文举华北理工大学电气工程学院河北唐山063210

精准的热负荷预测不仅可以提高用户舒适度,还可以有效降低能源消耗。为了提升热负荷预测的准确性,本研究提出了一种基于随机森林的并行CNN和TGLSTM的短期热负荷预测模型。首先,采用随机森林算法对特征进行筛选;其次,利用并行网络CNN和... 详细信息

精准的热负荷预测不仅可以提高用户舒适度,还可以有效降低能源消耗。为了提升热负荷预测的准确性,本研究提出了一种基于随机森林的并行CNN和TGLSTM的短期热负荷预测模型。首先,采用随机森林算法对特征进行筛选;其次,利用并行网络CNN和改进的LSTM分别提取时空特征;最后,将提取的特征与多头注意力机制动态结合。实验结果表明,并行CNN-TGLSTM-MA相较于传统的串行CNN-TGLSTM模型,在MAe和MSe方面分别降低了16.9%、26.8%,同时提升了3.5%的R2值,证明了所提出的并行CNN-TGLSTM-MA模型在短期热负荷预测方面的有效性和优越性,为热力系统供热负荷的精准调控提供了参考。

关键词：短期热负荷预测卷积神经网络转换门控长短期记忆网络多头注意力机制随机森林

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