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High Capacity Data Hiding in Encrypted Image Based on Compressive Sensing for Nonequivalent Resources 被引量:2
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作者 Di Xiao Jia Liang +2 位作者 qingqing ma Yanping Xiang Yushu Zhang 《Computers, Materials & Continua》 SCIE EI 2019年第1期1-13,共13页
To fulfill the requirements of data security in environments with nonequivalent resources,a high capacity data hiding scheme in encrypted image based on compressive sensing(CS)is proposed by fully utilizing the adapta... To fulfill the requirements of data security in environments with nonequivalent resources,a high capacity data hiding scheme in encrypted image based on compressive sensing(CS)is proposed by fully utilizing the adaptability of CS to nonequivalent resources.The original image is divided into two parts:one part is encrypted with traditional stream cipher;the other part is turned to the prediction error and then encrypted based on CS to vacate room simultaneously.The collected non-image data is firstly encrypted with simple stream cipher.For data security management,the encrypted non-image data is then embedded into the encrypted image,and the scrambling operation is used to further improve security.Finally,the original image and non-image data can be separably recovered and extracted according to the request from the valid users with different access rights.Experimental results demonstrate that the proposed scheme outperforms other data hiding methods based on CS,and is more suitable for nonequivalent resources. 展开更多
关键词 COMPRESSIVE SENSING encrypted IMAGE data hiding PREDICTION ERROR nonequivalent RESOURCES
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Estimate on spillover effect of environmental pollution between peripheral areas
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作者 qingqing ma Tongbin Zhang Jinkai Li 《Chinese Journal of Population,Resources and Environment》 2019年第3期254-266,共13页
Interaction of environmental pollution between peripheral areas has become a central topic in the field of resources and environment but little is known about the actual impact on peripheral areas in the current liter... Interaction of environmental pollution between peripheral areas has become a central topic in the field of resources and environment but little is known about the actual impact on peripheral areas in the current literature.This paper sets out a simultaneous equation model to investigate the spillover effect of environmental pollution between China's peripheral areas utilizing the panel data of 218 cities in China.Making use of indicators for measuring the impact on environmental pollution,it identifies that environmental pollution between cities of China has a significant two-way spillover effect.After standardization of variables,it is found that the spillover effect of peripheral areas on urban environmental pollution cannot be neglected.Nearly,a third of the environmental pollution level in a city is induced by the environmental pollution in peripheral areas.If the indicator of environmental pollution in peripheral areas is missing,wrong conclusions will be drawn.Therefore,government should shift the emphasis of environmental regulation from local to global,and improve the overall environmental quality through coordinated management of regional environment. 展开更多
关键词 Environmental pollution peripheral areas spillover effect panel simultaneous equation model
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A comprehensive meta-analysis of the association between three <i>IL</i>1B polymorphisms and rheumatoid arthritis
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作者 Dongjun Dai Lingyan Wang +13 位作者 Limin Xu Lingling Tang Xuting Xu Huadan Ye Xingyu Zhou Cheng Chen Guanghui Pan Ping Ru qingqing ma Yi Jiang Wenjing Yu Leiting Xu Meng Ye Shiwei Duan 《Advances in Bioscience and Biotechnology》 2014年第2期108-116,共9页
Rheumatoid arthritis (RA) is an immune-mediated chronic inflammatory disease that causes huge destruction to human body. IL1B encodes key mediator IL-1β protein, which plays an important role in the pathogenesis of i... Rheumatoid arthritis (RA) is an immune-mediated chronic inflammatory disease that causes huge destruction to human body. IL1B encodes key mediator IL-1β protein, which plays an important role in the pathogenesis of inflammatory syndromes. The aim of this study was to evaluate the association between IL1B polymorphisms and RA. A meta-analysis was performed on the association between three IL1B polymorphisms (IL1B-31: rs1143627;IL1B-511: rs16944;IL1B + 3954: rs1143634) and RA. A trend of significant association was observed between IL1B + 3954 and RA (p = 0.06, odd ratio (OR) = 1.19, 95% confidential interval (CI) = 1.00-1.42). A significant association was found in Europeans under the dominant model between IL1B-511T and RA (p = 0.03, OR = 0.89, 95% CI = 0.81-0.99). Our meta-analysis indicated that IL1B ? 511-T played a protective role against RA in Europeans, and that IL1B + 3954-T had the potential to increase the risk of RA. Future large-scale studies should be considered to confirm the association between IL1B polymorphisms and RA. 展开更多
关键词 RHEUMATOID ARTHRITIS META-ANALYSIS Polymorphism IL1B-511 Dominant Model
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多元介孔MOFs:通过调节表面亲水/疏水性实现酶固定化的多功能平台
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作者 冯玉晓 马庆庆 +5 位作者 王子辰 张群力 赵利雪 崔建东 杜英杰 贾士儒 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第5期386-398,共13页
作为高效的生物催化剂,酶在食品加工、医药制造、化学工业和能源开发等众多领域发挥着重要作用.然而,游离状态的酶由于存在稳定性差、易失活、难以回收利用及不适用于连续化生产等问题,限制了其广泛应用.为了解决上述难题,人们探索发展... 作为高效的生物催化剂,酶在食品加工、医药制造、化学工业和能源开发等众多领域发挥着重要作用.然而,游离状态的酶由于存在稳定性差、易失活、难以回收利用及不适用于连续化生产等问题,限制了其广泛应用.为了解决上述难题,人们探索发展了固定化酶技术.固定化酶不仅保留了原有的催化活性,而且在稳定性方面有了显著提升,从而极大地提高了酶的利用效率.随着固定化酶材料和酶工程领域的不断发展,固定化酶技术为酶的应用开辟了更广阔的前景.沸石-咪唑骨架材料-8(ZIF-8)作为一种金属-有机骨架(MOFs)材料,因其独特的结构特性而被广泛用作酶固定化载体.然而,ZIF-8的微孔结构和固有的疏水性,以及前体物2-甲基咪唑(2-MeIm)的质子化现象,常常影响固定化酶的活性.为克服这些限制,本文采用多元配体竞争和孔隙工程相结合的策略,设计并制备了一种具有可调节亲水/疏水表面的新型多元介孔MOFs(mMOFs),并用作酶固定化载体.在mMOFs的制备过程中,采用亲水性和配位能力更强的3-甲基-1H-1,2,4-三唑(3-MTZ)和5-甲基四唑(5-MTA)配体,以部分替代传统的2-MeIm配体.随后,这些多元配体(包括2-MeIm,3-MTZ和5-MTA)与七水硫酸锌结合,在甲醇溶液中通过自凝聚作用形成透明的胶体溶液,进而完全溶解在水中.在此过程中,七水硫酸锌发挥了软模板的作用,引导介孔的形成,从而成功制备出新型多元介孔mMOFs.接着,利用这些mMOFs作为酶固定化的载体,固定了辣根过氧化物酶(HRP)和葡萄糖氧化酶(GOx),并详细研究了其催化性能.结果表明,与传统的ZIF-8载体相比,以mMOFs为载体的固定化酶展现出了更高的酶活性和稳定性.催化性能提升主要归因于mMOFs的亲水性和介孔结构改善了酶和底物间的传质,同时2-MeIm的质子化效应减弱也为酶提供了优良的微环境,稳定了酶的构象.综上,本文采用多元配体竞争与孔隙工程相结合的策略,成功构建了一种具有可调节亲水/疏水表面的新型多元介孔mMOFs,并用于酶固定化,所得固定化酶表现出较好的催化性能.通过深入的研究,揭示了该固定化酶表现出良好催化性能的作用机制,为可控设计制备性能优越的、以MOFs为载体的固定化酶提供了新思路,并为进一步拓宽MOFs材料的应用范围提供了参考. 展开更多
关键词 介孔金属-有机骨架 竞争性配体 软模板 固定化酶
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Punicalagin prevents obesity-related cardiac dysfunction through promoting DNA demethylation in mice
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作者 Shengjie Pei Run Liu +10 位作者 qingqing ma Peng Jiang Xin He Zhongshi Qi Jiacheng Fang Xu Yang Zirui Yao Xiaoqian Liu Xianfeng Jing Lei Chen Duo Li 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1465-1474,共10页
The aim of this study was to investigate whether punicalagin(PU)could prevent obesity-related cardiac dysfunction by promoting DNA demethy lation,and to explore its possible mechanism.C57BL/6J mice were fed with stand... The aim of this study was to investigate whether punicalagin(PU)could prevent obesity-related cardiac dysfunction by promoting DNA demethy lation,and to explore its possible mechanism.C57BL/6J mice were fed with standard diet,high-fat diet(HFD),HFD supplemented with resveratrol,low-dose PU(LPU)and high-dose PU(HPU)for 8 weeks.Compared with HFD group,body weight was significantly lower in PU treatment groups,number of cardionwocytes and the protein level of myosin heavy chain 7B were significantly higher in PU treatment groups.Levels of 5-hydroxymethylcytosine and 5-formylcytosine were significantly lower in HFD group than in other groups.Compared with the HFD group,the protein level of ten-eleven translocation enzyme(TET)2 was significantly higher in PU treatment groups,p-AMP-activated protein kinase(AMPK)was significantly higher in LPU group.Levels of total antioxidant capacity and the protein levels of complexesⅡ/Ⅲ/Ⅴ,oxoglutarate dehydrogenase,succinate dehydrogenase B and fumarate hdrolase were significantly lower in HFD group than PU treatment group.The ratio of(succinic acid+fumaric acid)/a-ketoglutarate was significantly higher in HFD group than other groups.In conclusion,PU up-regulated TETs enzyme activities and TET2 protein stability through alleviating mitochondrial dysfunction and activating AMPK,so as to promote DNA demethylation,thus preventing obesity-related cardiac dysfunction. 展开更多
关键词 DNA demethylation Mitochondrial function Obesity-related cardiac dysfunction PUNICALAGIN Ten-eleven translocation family enzymes
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Hydrogenation of Alkylanthraquinone Over Pore-Expanded and Channel-Shortened Pd/SBA-15 被引量:1
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作者 Nan Wang qingqing ma +1 位作者 Enxian Yuan Li Wang 《Transactions of Tianjin University》 EI CAS 2019年第6期595-602,共8页
SBA-15 silica was synthesized by adding normal paraffin and alkyl benzene as swelling agents and using a low-temperature gelation procedure.Pd was then impregnated on SBA-15,yielding a catalyst.Characterizations of th... SBA-15 silica was synthesized by adding normal paraffin and alkyl benzene as swelling agents and using a low-temperature gelation procedure.Pd was then impregnated on SBA-15,yielding a catalyst.Characterizations of the catalyst by X-ray diffraction,N2 adsorption/desorption,scanning electron microscopy,transmission electron micrographs,X-ray photoelectron spectroscopy,in situ FTIR,and a hydrogenation test of 2-ethyl-anthraquinone reveal that the addition of C6-C9 normal paraffin and 1,3,5-triisopropylbenzene could enlarge the pore diameter without a significant loss of ordered structure.Moreover,the length of SBA-15 pore channels decreased significantly.However,the sizes of Pd particles increase as the pore diameter is enlarged.The largest pore size(13.6 nm)and short length of pore channels(ca.0.35μm)are achieved by adding n-hexane.As a result,this catalyst exhibits the highest hydrogenation activity with an approximately 100%improvement,compared with a conventionally synthesized catalyst in the absence of a swelling agent. 展开更多
关键词 HYDROGENATION ANTHRAQUINONE SBA-15 SWELLING agent Hydrogen PEROXIDE
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Observation on Flower Bud Differentiation of Crape Myrtle in Red Soil Environment 被引量:1
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作者 Linxue Shang Dandan ma +5 位作者 Sidan Hong Yu Zhao Guozhe Zhang qingqing ma Qun Wang Cuihua Gu 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第12期2607-2617,共11页
Flower bud differentiation is a key component of plant blooming biology and understanding how it works is vital for flowering regulation and plant genetic breeding,increasing the number and quality of flowering.Red so... Flower bud differentiation is a key component of plant blooming biology and understanding how it works is vital for flowering regulation and plant genetic breeding,increasing the number and quality of flowering.Red soil is the most widely covered soil type in the world,and it is also the most suitable soil type for crape myrtle planting.The flower buds of crape myrtle(Lagerstroemia indica)planted in red soil were employed as experimental materials in this study,and the distinct periods of differentiation were identified using stereomicroscopy and paraffin sectioning.We optimized the steps of dehydration,transparency,embedding,sectioning and staining when employing paraffin sections.When seen under a microscope,this optimization can make the cell structure of paraffin sections obvious,the tissue structure complete,and the staining clear and natural.The flower bud differentiation process is divided into 7 periods based on anatomical observations of the external morphology and internal structure during flower bud differentiation:undifferentiated period,start of differentiation period,inflorescence differentiation period,calyx differentiation period,petal differentiation period,stamen differentiation period,and pistil differentiation period.The differentiation time is concentrated from the end of May to mid-June.Crape myrtle flower bud differentiation is a complicated process,and the specific regulatory mechanism and affecting elements need to be investigated further. 展开更多
关键词 Crape myrtle flower bud differentiation morphological structure paraffin section
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Cross-linkedα-amylase aggregates on Fe3O4 magnetic nanoparticles modified with polydopamine/polyethyleneimine for efficient hydrolysis of starch 被引量:1
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作者 Jiandong Cui Xiuming Tang +3 位作者 qingqing ma Yuyan Chang Qunli Zhang Shiru Jia 《Particuology》 SCIE EI CAS CSCD 2024年第7期98-105,共8页
In this workα-amylase was immobilized on magnetic Fe3O4 nanoparticles with polyethylenimine(PEI)/polydopamine(PDA)coating or 3-aminopropyl triethoxysilane(APTES)for the first time via adsorption–precipitation–cross... In this workα-amylase was immobilized on magnetic Fe3O4 nanoparticles with polyethylenimine(PEI)/polydopamine(PDA)coating or 3-aminopropyl triethoxysilane(APTES)for the first time via adsorption–precipitation–cross-linking.Compared with the freeα-amylase,the resultant magnetic cross-linkedα-amylase aggregates(PEI/PDA-M-CLEAs and N-M-CLEAs)exhibited excellent thermal and storage stability as well as pH stability.After storage at 25°C for 60 days,freeα-amylase only retained 60%of its initial activity,while PEI/PDA-M-CLEAs and N-M-CLEAs retained 80%and 78%of their initial activities,respectively.Furthermore,N-M-CLEAs and PEI/PDA-M-CLEAs showed good reusability.After 6 repeated uses,PEI/PDA-M-CLEAs and N-M-CLEAs still maintained 65%and 62%of their initial activities,respectively.Especially,PEI/PDA-M-CLEAs and N-M-CLEAs exhibited higher starch hydrolysis efficiency than freeα-amylase.The maximum dextrose equivalent(DE)values of starch hydrolysis by PEI/PDA-M-CLEAs and N-M-CLEAs reached 29.24%and 28.79%within 90 min,respectively.However,the maximum DE values of starch hydrolysis by the freeα-amylase was only 27.89%even in 150 min.The magnetic cross-linkedα-amylase aggregates could be introduced as effective biocatalyst for industrial applications in production of maltose syrups. 展开更多
关键词 Α-AMYLASE Magnetic nanoparticles Functional modification Magnetic cross-linked enzyme aggregates Hydrolysis of starch
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Association of four GSTs gene polymorphisms with Parkinson disease: A meta-analysis
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作者 Dongjun Dai Yunliang Wang +15 位作者 Lingyan Wang Jinfeng Li Hanlin Zhou qingqing ma Xingyu Zhou Jun Pan Guanghui Pan Cheng Chen Limin Xu Ping Ru Hui Wang Shengqian Zhu Yuelong Lv Leiting Xu Meng Ye Shiwei Duan 《Advances in Bioscience and Biotechnology》 2014年第2期100-107,共8页
Parkinson disease (PD) is a neurological disorder with huge destruction to human body, which affects approximately 2% of the population aged 65 years or older. As antioxidants in the stress defence systems, glutathion... Parkinson disease (PD) is a neurological disorder with huge destruction to human body, which affects approximately 2% of the population aged 65 years or older. As antioxidants in the stress defence systems, glutathione S-transferases (GSTs) are dimeric cytosolic enzymes with an important role in the pathogenesis of PD. The aim of this study was to evaluate the association between the polymorphisms of GST genes and PD. Meta-analyses were conducted from 17 studies (38 stages) among 3419 cases and 5686 controls between four polymorphisms (GSTT1 deletion polymorphism;GSTM1 deletion polymorphism;GSTP1-104: rs1695;GSTP1-114: rs1799811) and PD. There is no significant association between the four GST gene variants and PD. A further subgroup study by ethnicity observed a risky role of GSTM1 deletion polymorphism with PD in Europeans (p = 0.013, OR = 1.126, 95% CI = 1.025-1.236), and a protective role of GSTM1 deletion polymorphism with PD in Latin Americans (p = 0.032, OR = 0.750, 95% CI = 0.577-0.975). Our meta-analysis suggested that GSTM1 deletion polymorphism increased the risk of PD in Europeans, but reduced the risk of PD in Latin Americans. Future large-scale studies might be needed to confirm the ethnic difference of GSTM1 deletion polymorphism, and to check whether there was significant association of PD for other GST genetic polymorphisms. 展开更多
关键词 Parkinson GSTM1 Deletion Polymorphism META-ANALYSIS Europeans GSTT1 GSTP1
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Analysis of moisture and total sugar content of Huizao based on surface images 被引量:1
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作者 Junxiong Zhang qingqing ma +2 位作者 Fen He Feng Qu Wei Li 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2018年第4期238-243,共6页
Moisture and total sugar content are two important internal qualities of Huizao.In order to explore their correlation with external qualities,a novel method of moisture and total sugar content analysis was proposed ba... Moisture and total sugar content are two important internal qualities of Huizao.In order to explore their correlation with external qualities,a novel method of moisture and total sugar content analysis was proposed based on surface images.Firstly,five geometric features and seven texture features of Huizao were obtained to be the external quality indexes by digital image processing technology.Secondly,the wrinkle degree as an important index was extracted by marked watershed segmentation algorithm.According to the external quality the Huizao samples were grouped,and the moisture and total sugar content were determined through physical and chemical methods.Lastly,the moisture and total sugar content and twelve external indexes were all processed by step discriminatory analysis.Meanwhile,the regression models of moisture content with short diameter,contrast,and wrinkle degree and total sugar with wrinkle degree were established.The coefficients of the model were 0.9992 and 0.9978 respectively,and all the significance was less than 0.01,which show that the regression equation and regression coefficient effect are highly significant.The results indicate that the moisture and total sugar content of Huizao are greatly correlated with the wrinkle degree.The moisture and total sugar content are the highest when the wrinkle degree is at 2 to 3 grade,and they decrease gradually with the wrinkle degree increasing.Moisture content shows positive correlation with the size of Huizao.The results of model analysis agree well with the experimental results,which can provide valuable reference for improving Huizao grade diversity. 展开更多
关键词 HUIZAO step discriminatory analysis moisture content total sugar
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A natural nano-platform:Advances in drug delivery system with recombinant high-density lipoprotein
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作者 Zhilong Xie Guohui Zhang +6 位作者 Ya Meng Yefei Tong Jian Deng Honghui Li qingqing ma Shisong Han Wenjun Ni 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第11期74-86,共13页
Developing natural nano-platforms with high biocompatibility and natural targeting ability represents great significance for drug delivery.High-density lipoprotein(HDL),a natural lipid-protein complex,plays important ... Developing natural nano-platforms with high biocompatibility and natural targeting ability represents great significance for drug delivery.High-density lipoprotein(HDL),a natural lipid-protein complex,plays important roles in physiological activities,particularly in reverse cholesterol transport(RCT)and be closely associated with atherosclerotic cardiovascular diseases.Recent studies have demonstrated that HDLs have the potential to serve as ideal drug carriers.Recombinant HDLs(r HDLs)have been used to encapsulate substances such as small interfering RNA(siRNA),drugs,and contrast agents,fully utilizing the biocompatibility and targeting ability of r HDL in the body and providing new strategies for drug delivery and disease treatment.In this review,we discussed in detail the basic principles of HDL as a drug delivery system,the mechanisms of targeted drug delivery,and several methods for preparing HDL nanoparticles.Afterward,we comprehensively reviewed the applications of HDL as a drug carrier in cardiovascular diseases,cancer treatment(such as glioblastoma,breast cancer,hepatocellular carcinoma and urologic cancers)and some other fields.Finally,we reviewed the therapeutic effects and safety of HDL nanoparticles in clinical studies.Through a review and summary of these research advances,we aim to fully understand the potential of HDL as a drug carrier in clinical applications,providing valuable references and guidance for future research and expedites the translational application of HDL as drug carriers. 展开更多
关键词 High-density lipoproteins Drug delivery APOLIPOPROTEIN Targeting mechanisms HDL nanoparticle preparation Cardiovascular disease Cancer treatment
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基于红外相机技术调查佛坪国家级自然保护区兽类和鸟类多样性 被引量:18
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作者 马亦生 马青青 +6 位作者 何念军 朱大鹏 赵凯辉 刘红彩 李帅 孙亮 唐流斌 《生物多样性》 CAS CSCD 北大核心 2020年第2期226-230,共5页
2015年1月至2017年12月,在陕西佛坪国家级自然保护区57条巡护样线上布设130台红外相机,对兽类和鸟类多样性进行调查。累计相机工作日101,220天,共捕获独立有效事件36,100次,其中兽类独立照片30,563张,鸟类3,244张。共记录到野生兽类6目1... 2015年1月至2017年12月,在陕西佛坪国家级自然保护区57条巡护样线上布设130台红外相机,对兽类和鸟类多样性进行调查。累计相机工作日101,220天,共捕获独立有效事件36,100次,其中兽类独立照片30,563张,鸟类3,244张。共记录到野生兽类6目15科29种,相对多度较高的前5个物种依次是秦岭羚牛(Budorcasbedfordi,RAI=11.53)、野猪(Sus scrofa, RAI=4.80)、小麂(Muntiacus reevesi, RAI=4.35)、大熊猫(Ailuropoda melanoleuca, RAI=1.81)和中国豪猪(Hystrixhodgsoni,RAI=1.13)。共记录到鸟类8目14科54种,相对多度最高的前5个物种依次是红腹锦鸡(Chrysolophus pictus, RAI=0.97)、红腹角雉(Tragopan temminckii, RAI=0.74)、紫啸鸫(Myophonus caeruleus,RAI=0.51)、红嘴蓝鹊(Urocissa erythrorhyncha, RAI=0.13)、黑领噪鹛(Garrulax pectoralis, RAI=0.12)。保护区鸟类新记录4种,包括白眉地鸫(Geokichla sibirica)、白眉鸫(Turdus obscurus)、长尾地鸫(Zoothera dixoni)和灰脸鵟鹰(Butastur indicus);保护区兽类新记录1种,为亚洲狗獾(Meles leucurus)。本研究利用红外相机技术客观记录了佛坪国家级自然保护区兽类和鸟类的本底情况,不仅初步了解了保护区内的野生动物分布,而且更新了保护区鸟类资源数据库,为保护区未来的保护和管理工作提供了数据基础。 展开更多
关键词 佛坪国家级自然保护区 红外相机技术 兽类 鸟类 生物多样性
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