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Corrigendum to"Topographic complexity drives trait composition as well as functional and phylogenetic diversity of understory plant communities in microrefugia:New insights for conservation"[Forest Ecosyst.12(2025)100278]
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作者 Kata Frei Anna E-Vojtkó +6 位作者 Csaba Tölgyesi András Vojtkó Tünde Farkas LászlóErdős Gábor Li Ádám Lőrincz Zoltán Bátori 《Forest Ecosystems》 2025年第3期536-538,共3页
The authors regret that an error occurred during the preparation of their article:One of the official databases,which was used for functional trait collections,contained an incorrect term–'chametophytes'–for... The authors regret that an error occurred during the preparation of their article:One of the official databases,which was used for functional trait collections,contained an incorrect term–'chametophytes'–for the life form category'chamaephytes'.Unfortunately,this incorrect term was used throughout the article following the nomenclature of this official database:in one instance in the main text,in Fig.3 and its caption,in Fig.5,and in two instances in the supplementary material. 展开更多
关键词 functional diversity functional trait collectionscontained understory plant communities supplementary material phylogenetic diversity CORRIGENDUM topographic complexity official database
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Management of sessile oak(Quercus petraea(Matt.)Liebl.),a major forest species in Europe
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作者 Valeriu‑Norocel Nicolescu Torsten Vor +19 位作者 Robert Brus Martina Đodan Sanja Perić Vilém Podrázský Siniša Andrašev Evgeni Tsavkov Sezgin Ayan Cengiz Yücedağ Pande Trajkov Dana Dina Kolevska Cornelia Buzatu‑Goanță Michal Pástor Vladimír Mačejovský Juraj Modranský Marcin Klisz Wojciech Gil Vasyl Lavnyy Palle Madsen Nicola La Porta Debbie Bartlett 《Journal of Forestry Research》 2025年第5期23-59,共37页
Sessile oak(Quercus petraea(Matt.)Liebl.)is widely distributed across most of Europe particularly the hills and lower mountain ranges,so is considered“the oak of the mountains”.This species grows on a wide variety o... Sessile oak(Quercus petraea(Matt.)Liebl.)is widely distributed across most of Europe particularly the hills and lower mountain ranges,so is considered“the oak of the mountains”.This species grows on a wide variety of soils and at altitudes ranging from sea level to 2200 m,especially in Atlantic and sub-Mediterranean climates,and it is sensitive to low winter temperatures,early and late frosts,as well as high summer temperatures.Sessile oak forms both pure and mixed stands especially with broadleaves such as European beech,European hornbeam,small-leaved lime and Acer spp.These form the understorey of sessile oak stands,promoting the natural shedding of lower branches of the oak and protecting the trunk against epicormic branches.Sessile oak is a long-lived,light-demanding and wind-firm species,owing to its taproot and heart-shaped root system.Its timber,one of the most valuable in Europe,is important for fur-niture-making(both solid wood and veneer),construction,barrels,railway sleepers,and is also used as fuelwood.It is one of the few major tree species in Europe that is regener-ated by seed(naturally or artificially)and by stump shoots in high forest,coppice-with-standards and coppice forests.Sessile oak forests are treated in both regular and irregular systems involving silvicultural techniques such as uniform shelterwood,group shelterwood,irregular shelterwood,irregular high forest,coppice-with-standards and simple coppice.Young naturally regenerated stands are managed by weeding,release cutting and cleaning-respacing,keeping the stands quite dense for good natural pruning.Plantations are based on(1)2-4-year old bare-root or container-grown seedlings produced in nurseries using seeds from genetic resources,seed stands and seed orchards.The density of sessile oak plantations(mostly in rows,but also in clusters)is usually between 4000 and 6000 ind.ha^(−1).Sessile oak silviculture of mature stands includes crown thinning,focus-ing on final crop trees(usually a maximum of 100 ind.ha^(−1))and targeting the production of large-diameter and high quality trees at long rotation ages(mostly over 120 years,sometimes 250-300 years).In different parts of Europe,conversion of simple coppices and coppice-with-standards to high forests is continuing.Even though manage-ment of sessile oak forests is very intensive and expensive,requiring active human intervention,the importance of this species in future European forests will increase in the con-text of climate change due to its high resistance to distur-bance,superior drought tolerance and heat stress resistance. 展开更多
关键词 Sessile oak Ecological requirements Timber VULNERABILITIES MANAGEMENT
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Research on the degradation behaviors of biomedical Mg-2 wt.% Zn alloy under a biliary environment in vitro and in vivo
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作者 Hongzhou Peng Zijun Gong +7 位作者 Rui Zan Wei Wang Han Yu Yu Sun Chaolin Ma Wenhui Wang Tao Suo Xiaonong Zhang 《Journal of Magnesium and Alloys》 2025年第3期1066-1077,共12页
Magnesium and its alloys have been initially applied to biliary tract surgery.Currently,few reports on the degradation behavior of magnesium in the bile environment were investigated.Thus,in-depth research on the degr... Magnesium and its alloys have been initially applied to biliary tract surgery.Currently,few reports on the degradation behavior of magnesium in the bile environment were investigated.Thus,in-depth research on the degradation behavior of Mg and its alloys in bile is beneficial to the further application of Mg in biliary tract surgery.In this study,the degradation behavior of HP-Mg(HPM)and Mg-2 wt.%Zn(MZ2)alloys in human bile and Hanks balanced salt solution(HBSS)was systematically investigated.The MZ2 alloy biliary stent was implanted into the porcine common bile duct to study the degradation behavior of MZ2 alloy in vivo,and to verify the biosafety of MZ2 alloys degradation in the bile duct.It was found that the degradation product layer formed by MZ2 alloys in bile consisted of three layers,including organic matter(fatty acid,etc.),calcium and magnesium phosphate,and Mg(OH)2/MgO,respectively from the outside to the inside.The multi-layered degradation product layer slowed down the corrosion of the Mg matrix.During the 21 days of stent implantation,the degradation rate of the MZ2 stent was about 0.83 mm/y,there was no blockage and stenosis of the tube diameter,and the bile drainage function was normal. 展开更多
关键词 Mg-Zn alloy Human bile Biliary stent Corrosion Stratified structure.
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Influence of pile-up on nanoindentation measurements in Cu-2wt.%Be samples with precipitates 被引量:1
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作者 S.MONTECINOS S.TOGNANA W.SALGUEIRO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第11期2340-2350,共11页
The influence of pile-up on the nanoindentation measurements in Cu 2wt.%Be samples with precipitates was carefully studied.The precipitates were formed by aging treatments for 1 h at different temperatures between 540... The influence of pile-up on the nanoindentation measurements in Cu 2wt.%Be samples with precipitates was carefully studied.The precipitates were formed by aging treatments for 1 h at different temperatures between 540 and 680 K.The load depth curves were analyzed using the classical Oliver and Pharr method,and the obtained elastic modulus and hardness were compared with values estimated by other techniques.An important level of pile-up was found in samples with precipitates and differences in the load depth curves were observed between the unaged and aged samples.A correction of the contact depth considering the pile-up proposed by Loubet was used for hardness estimation.For the determination of the elastic modulus,an approach based on the relation between the ratio of unloading work to indentation total work,with the ratio H/Er(H is the hardness;Er is the reduced modulus),was employed.A specific relation between both parameters was developed. 展开更多
关键词 PILE-UP nanoindentation measurement copper alloy PRECIPITATION microstructure mechanical properties
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t.c.electronic M300双引擎多功能效果器的使用
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《电声技术》 北大核心 2004年第11期77-77,共1页
关键词 M300 引擎 机箱 处理器 发送 压缩 创建 效果器 延时 移相
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数字动态处理器——t.c.electronicC300
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《电声技术》 2006年第5期86-86,共1页
关键词 动态处理器 C300 electronic公司 法兰克福 数字处理 BIT 多频段 音响
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Change in Mass of Spinning Black Holes w.r.t. the Angular Momentum
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作者 Dipo Mahto Anuradha Kumari 《Journal of Modern Physics》 2018年第5期1037-1042,共6页
Mahto et al. have shown &delta;S&ge;0 and M2=a*J by using the first law of the black hole mechanics in the vacuum and Einstein mass-energy equivalence relation specially for spinning black holes. In the presen... Mahto et al. have shown &delta;S&ge;0 and M2=a*J by using the first law of the black hole mechanics in the vacuum and Einstein mass-energy equivalence relation specially for spinning black holes. In the present paper, this work is extended to propose a model for the change in mass of the spinning black holes due to corresponding change in the angular momentum for maximum & half spin parameter of black holes (a* = 1 & 1/2) and calculated their values for different test black holes in XRBs and AGN. We have also shown that the change in mass of the spinning black holes due to corresponding change in the angular momentum for maximum spinning rate of black holes (a* = 1) is double to that of the spinning black holes having spinning parameter (a* = 1/2). 展开更多
关键词 SPINNING Black HOLES ANGULAR MOMENTUM SPINNING Parameter
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Change in Energy of Non-Spinning Black Holes w.r.t. the Change in Mass
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作者 Dipo Mahto Rama Nand Mehta +1 位作者 Neeraj Pant Raj Kumar Sah 《International Journal of Astronomy and Astrophysics》 2013年第1期49-56,共8页
The present work discusses the derivation of the formula for the change in energy of non-spinning black holes with respect to the change in mass (dE/dM), which gives a constant quantity equal to 8.9998 x 1016 Joule/kg... The present work discusses the derivation of the formula for the change in energy of non-spinning black holes with respect to the change in mass (dE/dM), which gives a constant quantity equal to 8.9998 x 1016 Joule/kg in both categories of X-ray binaries (XRBs) and Active Galactic Nuclei (AGN). This formula can be used to justify the life time of black hole given by Γ = 2.098(M/Mο)3 x 1067 years as proposed by Stephen Hawking, where M and Mο are the mass of the black hole and the sun respectively. The authors also calculate the change in energy and mass of non-spinning black holes with respect to the change in the radius of event horizon as well as (dE/dM) for different test non-spinning black holes in X-ray binaries (XRBs) and Active Galactic Nuclei (AGN). 展开更多
关键词 Life Time XRBs AGN ENERGY
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Entropy Change of Non-Spinning Black Holes w.r.t. the Radius of Event Horizon in AGN
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作者 Dipo Mahto Md. Shams Nadeem +2 位作者 Umakant Prasad Abhay Kumar K. M. Singh 《Journal of Modern Physics》 2013年第3期321-326,共6页
In this research paper, we have used the formula for the change in entropy of Non-spinning black holes with respect to the change in the radius of event horizon (Mahto et al. 2012) and entropy of black holes (Hawking ... In this research paper, we have used the formula for the change in entropy of Non-spinning black holes with respect to the change in the radius of event horizon (Mahto et al. 2012) and entropy of black holes (Hawking 1973 & Mahto et al. 2012) to calculate their values in Active Galactic Nuclei (AGN) which shows that the variation of change in entropy of black holes with respect to the radius of the event horizon/entropy of black holes with increasing the values of the radius of the event horizon of different test Non-spinning black holes are like a wave-pattern. 展开更多
关键词 RADIUS of Event-Horizon AGN Entropy
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New Continuum and Polarization Observations of the Cygnus Loop with FAST.II.Images and Analyses
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作者 Xiao-Hui Sun Xu-Yang Gao +4 位作者 Wolfgang Reich Peng Jiang Di Li Huirong Yan Xiang-Hua Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第12期249-259,共11页
We present total-intensity and polarized-intensity images of the Cygnus Loop supernova remnant(SNR)observed by the Five-hundred-meter Aperture Spherical radio Telescope.The high angular-resolution and high-sensitivity... We present total-intensity and polarized-intensity images of the Cygnus Loop supernova remnant(SNR)observed by the Five-hundred-meter Aperture Spherical radio Telescope.The high angular-resolution and high-sensitivity images enable us to thoroughly compare the properties of the northern part with the southern part of the SNR.The central filament in the northern part and the southern part have a similar foreground rotation measure,meaning their distances are likely similar.The polarization analysis indicates that the random magnetic field is larger than the regular field in the northern part,but negligible in the southern part.The total-intensity image is decomposed into components of various angular scales,and the brightness-temperature spectral index of the shell structures in the northern part is similar to that in the southern part in the component images.All the evidence suggests that the northern and southern parts of the Cygnus Loop are situated and thus evolved in different environments of interstellar medium,while belonging to the same SNR. 展开更多
关键词 ISM:supernova remnants ISM:magnetic fields POLARIZATION techniques:polarimetric
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Effects of inclusion of purple prairie clover (Dalea purpurea Vent.)with native coolseason grasses on in vitro fermentation and in situ digestibility of mixed forages
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作者 Kai Peng Gemma L.Gresham +5 位作者 Tim A.McAllister Zhongjun Xu Alan Iwaasa Mike Schellenberg Alex V.Chaves Yuxi Wang 《Journal of Animal Science and Biotechnology》 CAS CSCD 2020年第2期563-576,共14页
Background:Incorporation of legume species into native North American pastures is considered an effective method to increase native pasture productivity and improve the nutritive value of forage.This study evaluated t... Background:Incorporation of legume species into native North American pastures is considered an effective method to increase native pasture productivity and improve the nutritive value of forage.This study evaluated the effects of inclusion of purple prairie clover(PPC,Dalea purpurea Vent.),a native legume forage,with native coolseason grasses on the in vitro fermentation and in situ digestibility of mixed forages.Methods:Whole plant PPC and mixtures of cool-season grasses were harvested when the PPC reached the vegetative(VEG),full flower(FL)and seedpod(SP)stages,and were combined in ratios(DM basis)of 0:100,25:75,50:50,75:25 and 100:0 at each maturity.In vitro ruminal incubations using these mixtures were conducted for 48 h to determine gas production(GP),in vitro DM disappearance(IVDMD),total volatile fatty acids(VFA)and ammonia-N production.Mixtures of forages harvested when the PPC reached the FL stage and 50:50 mixture of forages harvested at VEG,FL and SP stages were incubated in the rumen of three heifers for 0,2,6,12,24,48,72 and 96 h to determine in situ degradabilities of DM,neutral detergent fibre(aNDF)and crude protein(CP).Results:Contents of aNDF and ADF increased(P<0.01),while CP decreased(P<0.001)as PPC matured.Concentrations of extractable condensed tannins in PPC ranked as FL>VEG>SP(P<0.05).Regardless of PPC proportions in the mixture,GP decreased(P<0.05)with increasing PPC maturity.Increasing PPC proportions linearly increased(P<0.001)GP,IVDMD and total VFA at VEG,but linearly decreased(P<0.001)them at SP.Irrespective of PPC maturity,ammonia-N production linearly increased(P<0.01)with increasing proportions of PPC and the concentration was higher(P<0.05)at VEG than at FL and SP stages.Increasing proportion of PPC at either maturity linearly increased(P<0.001)molar percentage of acetate(A)and branched-chain VFA,but linearly decreased(P<0.001)molar percentage of propionate(P),resulting in a linearly increase(P<0.001)in the A:P ratio.Increasing FL PPC in the mixture linearly and quadratically(P<0.01)increased a(soluble fraction),but linearly and quadratically decreased(P<0.01)b(potentially degradable fraction)for DM and aNDF,resulting in linear(P<0.05)and quadratic(P<0.01)increases in DM and aNDF maximum potential degradabilities(a+b).Effective degradabilities of DM and aNDF were also linearly and quadratically increased(P<0.05),and CP was quadratically increased(P<0.05)with increasing FL PPC,with the greatest effective degradability being observed with ratios between 50:50 and 75:25.Ruminal maximum potential degradabilities of DM and aNDF decreased(P<0.001)as the forage matured.Effective degradability of DM ranked as VEG>FL>SP(P<0.001),whereas the effective degradability of aNDF was similar between VEG and FL and both were greater(P<0.01)than SP.Conclusions:Inclusion of vegetative PPC in a mixed forage diet resulted in the greatest digestibility and incorporation of PPC before seedpod stage with native grasses had a positive effect on ruminal fermentation.Effects of PPC on ruminal digestion depend on both the stage of maturity and its proportion in mixed legume-grass pastures.Pastures containing 50%of PPC in full flower stage would likely provide the greatest quality diet to grazing ruminants subject to potential animal selectivity. 展开更多
关键词 Condensed tannins Cool-season grass In vitro fermentation In situ digestibility Purple prairie clover
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Effect of Different Concentrations of the Suspensions of B.amyloliquefaciens and T.harzianum on the Development of C.acutatum
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作者 Rababe Es-Soufi Houda Tahiri +4 位作者 Latifa Azaroual Aicha El Oualkadi Patrick Martin Alain Badoc Ahmed Lamarti 《Advances in Microbiology》 2020年第3期72-81,共10页
The effect of nine isolates of Bacillus amyloliquefaciensand one strain of Trichoderma harzianum, TR, on mycelial growth and germination of Colletotrichum acutatum were studied. The nine isolates were identified as Ba... The effect of nine isolates of Bacillus amyloliquefaciensand one strain of Trichoderma harzianum, TR, on mycelial growth and germination of Colletotrichum acutatum were studied. The nine isolates were identified as Bacillus amyloliquefaciens. The efficacy of isolates was tested, at different concentrations. Results showed that one Bacillus isolates (Bc2) and TR were more effective at the lower concentration tested (3 × 105 CFU/ml and 105 conidia/ml). 展开更多
关键词 BIOCONTROL Concentration INOCULUM Bacillus amyloliquefaciens Trichoderma harzianum Colletotrichum acutatum
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Phytochemical Profile, Antioxidant, and Anti-Inflammatory Activities, Safety of Use and Spasmolytic Effects of Aqueous Decoction Extract of Diospyros mespiliformis Leaves Hochst. ex A. DC. (Ebenaceae) on the Isolated Duodenum of Rat
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作者 Mathieu Nitiéma Pegdwendé Esther Ouédraogo +12 位作者 Tata Kadiatou Traoré Oumarou Maman Noura Boukaré Kaboré Wendkouni Leila Marie Esther Bélem-Kabré Windingoudi Rimwagna Christian Ouédraogo Moumouni Koala Bruno Nébié Abdel Magid Arsène Ouoba Makumbu Joseph Makaya Sylvain Ilboudo Lazare Belemnaba Noufou Ouédraogo Sylvin Ouédraogo 《Pharmacology & Pharmacy》 2023年第12期513-529,共17页
Diospyros mespiliformis Hochst. ex A. DC. (Ebenaceae) is a multi-use plant, including for therapeutic purposes. It is used in alternative medicine in Burkina Faso to treat conjunctivitis, menorrhagia, dysentery, and d... Diospyros mespiliformis Hochst. ex A. DC. (Ebenaceae) is a multi-use plant, including for therapeutic purposes. It is used in alternative medicine in Burkina Faso to treat conjunctivitis, menorrhagia, dysentery, and diarrhea. The aim of our study was to evaluate the chemical profile, antioxidant and anti-inflammatory activities, safety of use and spasmolytic effects of the aqueous decoction of Diospyros mespiliformis leaves. Phytochemical screening by HPTLC and assay of compounds of interest were carried out. Four methods were used to assess antioxidant activity. Inhibitory activity against 15-lipoxygenase and phospholipase A2 was assessed. Acute oral toxicity of the extract was tested on female mice (NMRI). Following these tests, the extract contained bioactive compounds of interest such as flavonoids, tannins, sterols, triterpenes, and saponosides. The total phenolic and flavonoid contents of the aqueous decoctate were 70.59 ± 3.20 mg EAT/g and 31.57 ± 0.78 mg EQ/g respectively. The extract was less active than Trolox with inhibitory concentrations of 50% (IC<sub>50</sub>) for the ABTS, DPPH, FRAP, and LPO tests of 7.53 ± 0.08 μg/mL, 29.47 ± 0.06 μg/mL, 1128.83 ± 4.82 mol EAA/g, and 32.30 ± 1.60 μg/mL respectively. The extract has an anti-inflammatory effect with inhibition of phospholipase A2 compared to betamethasone. In addition, the aqueous extract produced an antispasmodic effect with Emax of 70% and 80% respectively during contractions induced by BaCl<sub>2</sub> and ACh. Finally, this study provided basic scientific data and could justify the use of D. mespiliformis leaves in the treatment of diarrhea. 展开更多
关键词 Diospyros mespiliformis PHYTOCONSTITUENTS Antioxidants Acute Oral Toxicity SPASMOLYTIC LEAVES
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IntervalTree+结构的函数式建模、机械化验证及其应用
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作者 左正康 张晗庆 +1 位作者 王昌晶 游珍 《电子学报》 北大核心 2025年第2期474-482,共9页
区间树(IntervalTree)是一种对动态集合进行维护的搜索树,可用于高效地存储和搜索区间集合.当前实现了IntervalTree在Isabelle/HOL的建模与验证,其区间信息是在二叉搜索树上进行扩充的,IntervalTree结构支持的基本操作时间复杂度较高.为... 区间树(IntervalTree)是一种对动态集合进行维护的搜索树,可用于高效地存储和搜索区间集合.当前实现了IntervalTree在Isabelle/HOL的建模与验证,其区间信息是在二叉搜索树上进行扩充的,IntervalTree结构支持的基本操作时间复杂度较高.为此,本文对IntervalTree结构的节点附加额外颜色信息且保证树的平衡,提出了IntervalTree+结构,相较于IntervalTree结构的实现,插入和删除等操作最坏时间复杂度O(n)改进到O(log n).然后使用Isabelle定理证明器对IntervalTree+结构及其操作函数进行了函数式建模,对其不变量进行了机械化验证,保证了IntervalTree+结构操作函数的正确性和可靠性.进一步,首次提出一种区域匹配算法的通用验证规约,旨在解决一系列的区域匹配算法正确性验证问题.提出的IntervalTree+结构通过严格的机械化验证,且操作最坏时间复杂度相较于IntervalTree结构由O(n)优化到O(log n),可应用于区域匹配、视觉日志和评估模型等相关算法优化. 展开更多
关键词 区间树 IntervalTree+ 函数式建模 机械化验证 区域匹配算法 Isabelle定理证明器
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LsSAT2与LsAAE3互作调控山黧豆ODAP水平
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作者 刘晓宁 张颖 +5 位作者 蔡曼蕾 马昊 苗智博 曹宁 连荣芳 徐全乐 《作物学报》 北大核心 2025年第8期2220-2227,共8页
丝氨酸乙酰基转移酶LsSAT2(serine acetyltransferase,SAT)是山黧豆中神经活性成分β-N-草酰-L-α,β-二氨基丙酸(β-N-oxalyl-L-α,β-diaminopropionic acid,β-ODAP)生物合成的关键酶。为进一步分析LsSAT2的功能及其活性调控,本研究... 丝氨酸乙酰基转移酶LsSAT2(serine acetyltransferase,SAT)是山黧豆中神经活性成分β-N-草酰-L-α,β-二氨基丙酸(β-N-oxalyl-L-α,β-diaminopropionic acid,β-ODAP)生物合成的关键酶。为进一步分析LsSAT2的功能及其活性调控,本研究构建了LsSAT2过表达山黧豆毛状根株系,利用免疫沉淀和质谱联用技术(immunoprecipitation mass spectrum,IP-MS)筛选到了LsSAT2的潜在互作蛋白草酰辅酶A合成酶LsAAE3,通过蛋白对接、酵母双杂交(yeast two-hybrid,Y2H)、蛋白质下拉试验(pull down assay)等进行蛋白互作验证及功能分析。结果表明,利用IP-MS从LsSAT2过表达山黧豆毛状根株系中筛选到其潜在的互作蛋白LsAAE3;Y2H和Pull down试验证实了LsAAE3与LsSAT2存在蛋白互作关系;蛋白对接分析表明,LsSAT2通过羧基末端与LsAAE3发生蛋白互作。LsSAT2在山黧豆毛状根株系中的过表达使得β-ODAP水平相比对照降低52.4%,LsAAE3在山黧豆毛状根株系中的过表达则使得β-ODAP水平升高55.9%。上述结果加深了对山黧豆β-ODAP生物合成调控的理解。 展开更多
关键词 山黧豆 三七素 丝氨酸乙酰基转移酶 草酰辅酶A合成酶 蛋白互作
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基于T细胞效应的多机器鱼环境免疫协作探测
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作者 江亚峰 王舜 +2 位作者 张亮 刘维 袁明新 《舰船科学技术》 北大核心 2025年第4期154-162,共9页
为提高多机器鱼在未知复杂水域中的探测质量和效率,提出了基于T细胞效应的环境免疫协作探测模型和算法。首先基于Jerne的独特型免疫网络假设构建多机器鱼基本免疫协作探测网络模型;然后根据已探测区域的环境信息,借鉴生物T细胞效应,构... 为提高多机器鱼在未知复杂水域中的探测质量和效率,提出了基于T细胞效应的环境免疫协作探测模型和算法。首先基于Jerne的独特型免疫网络假设构建多机器鱼基本免疫协作探测网络模型;然后根据已探测区域的环境信息,借鉴生物T细胞效应,构建多机器鱼的互联耦合免疫协作探测网络模型;最后进行算法设计和实验测试。实验结果表明,与基于免疫机理的完全探测算法和基于生物熵的免疫协作探测算法相比,文中算法的覆盖率平均提高了7.6%,重复探测率平均降低了32.8%,平均探测步数平均降低了11.6%,平均重复探测步数平均降低了24.7%,验证了未知复杂环境中多机器鱼互联耦合免疫协作探测网络模型的有效性。 展开更多
关键词 多机器鱼 环境探测 免疫网络模型 独特型免疫网络假设 T细胞效应
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t(16;21)(p11;q22)/FUS∷ERG阳性急性髓系白血病的基因突变谱和预后分析
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作者 董晓燕 邬成业 +3 位作者 李玉龙 程薇 商保军 朱尊民 《临床血液学杂志》 2025年第1期63-68,共6页
目的:旨在探讨携带t(16;21)(p11;q22)/FUS∷ERG融合基因的急性髓系白血病(acute myeloid leukemia,AML)患者的临床生物学及预后特征。方法:回顾性分析2015年12月—2023年8月在河南省人民医院收治的12例t(16;21)(p11;q22)/FUS∷ERG阳性AM... 目的:旨在探讨携带t(16;21)(p11;q22)/FUS∷ERG融合基因的急性髓系白血病(acute myeloid leukemia,AML)患者的临床生物学及预后特征。方法:回顾性分析2015年12月—2023年8月在河南省人民医院收治的12例t(16;21)(p11;q22)/FUS∷ERG阳性AML患者的临床和实验室数据,并进行文献复习。结果:t(16;21)(p11;q22)/FUS∷ERG阳性AML占同期初诊AML患者的1.28%(12/935)。患者中男9例,女3例;FAB分型为M2型9例,M4/5型3例。7例患者在诊断时骨髓原始细胞可见空泡形成。所有患者的免疫表型均表达CD56和CD123。染色体核型分析均显示t(16;21)易位,其中7例伴有附加染色体异常。FUS∷ERG融合基因均检测阳性,基因突变情况:PTPN1150.0%(3/6)、NRAS 36.4%(4/11)、BCOR 22.2%(2/9)、RUNX118.2%(2/11)、TET218.2%(2/11)、WT111.1%(1/9)。汇总国内外文献中基因突变信息,突变率最高为PTPN11,占26.7%(12/45),其次为NRAS,占23.5%(8/34),其他常见突变基因为TET2、RUNX1、ASXL1、DNMTA、BCOR等。研究中11例患者诱导化疗后完全缓解率为72.7%,复发率为37.5%;3例患者接受了造血干细胞移植(hematopoietic stem cell transplantation,HSCT),其中2例移植后复发/死亡。11例患者的中位生存期为15个月(95%CI 9.092~20.908)。结论:t(16;21)(p11;q22)/FUS∷ERG阳性AML是一类罕见的具有特定遗传学特征的AML亚型,具有独特的临床生物学和基因表达谱特征,总体预后较差。HSCT效果可能有限,亟需探索新的靶向治疗方法。 展开更多
关键词 白血病 髓样 急性 FUS∷ERG 融合基因 预后
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基于改进AOD-Net算法的道路交通去雾方法
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作者 宋宇博 李紫玄 李祯 《现代信息科技》 2025年第10期39-44,49,共7页
针对交通图像去雾后容易出现细节信息丢失、图像清晰度降低等问题,提出了一种改进的AOD-Net算法。针对特征提取深度不足导致信息丢失的问题,设计了级联卷积网络,以更准确地识别和提取图像中的细粒度特征;同时,为解决AOD-Net算法未充分... 针对交通图像去雾后容易出现细节信息丢失、图像清晰度降低等问题,提出了一种改进的AOD-Net算法。针对特征提取深度不足导致信息丢失的问题,设计了级联卷积网络,以更准确地识别和提取图像中的细粒度特征;同时,为解决AOD-Net算法未充分考虑特征权重、易导致信息冗余的问题,引入自适应权重分配机制,根据不同信息的重要性进行动态调整,从而避免细节信息的丢失。此外,通过引入Smooth L1损失函数优化模型,提升了去雾后图像的清晰度。实验在公开数据集RESIDE上进行,结果表明,与基线模型相比,改进算法的峰值信噪比(PSNR)提升了0.52 dB,结构相似性(SSIM)提升了0.0868,信息熵提升了0.76。去雾后的图像更加清晰,有效提升了图像质量。与其他算法相比,该方法在处理交通场景图像时表现出显著优势。 展开更多
关键词 图像去雾 AOD-Net算法 级联卷积 注意力机制
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基于增强CT术前诊断增殖型肝细胞癌的临床价值及预后分析 被引量:1
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作者 成杰 魏晓凡 +2 位作者 陈伟 叶小龙 张维 《陆军军医大学学报》 北大核心 2025年第7期708-719,共12页
目的基于增强CT影像特征构建增殖型肝细胞癌(hepatocellular carcinoma,HCC)的术前预测模型并进行预后分析。方法采用回顾性病例-对照研究方法。共纳入经病理证实为HCC的患者603例;其中陆军军医大学第一附属医院519例,以7︰3的比例随机... 目的基于增强CT影像特征构建增殖型肝细胞癌(hepatocellular carcinoma,HCC)的术前预测模型并进行预后分析。方法采用回顾性病例-对照研究方法。共纳入经病理证实为HCC的患者603例;其中陆军军医大学第一附属医院519例,以7︰3的比例随机分为训练组(n=363)和内部验证组(n=156);将重庆医科大学附属第二医院84例患者作为外部验证组。患者术前均行腹部CT增强检查,观察增殖型与非增殖型HCC患者临床资料情况及CT影像学特征。采用二元Logistic回归分析筛选增殖型HCC的独立危险因素,构建列线图预测模型,通过受试者工作特征曲线(receiver operating characteristic curve,ROC)、ROC曲线下面积(area under curve,AUC)评价其诊断效能,绘制校准曲线、决策曲线(decision curve analysis,DCA)评估列线图模型的校准性能和临床应用价值,并在内部验证组和外部验证组对模型进行验证。使用Kaplan-Meier生存曲线对比增殖型和非增殖型HCC的预后。结果多因素分析结果示乙型肝炎病毒脱氧核糖核酸(hepatitis B virus deoxyribonucleic acid,HBV-DNA)定量阴性、肿瘤包膜不完整、瘤内坏死或缺血(≥20%)、动脉期环形高强化是预测增殖型HCC的独立预测因子(P<0.05)。基于以上临床影像特征绘制预测增殖型HCC的列线图,在训练组AUC为0.805(95%CI:0.756~0.854),敏感度83.19%,特异度64.80%;在内部验证组中,AUC为0.793(95%CI:0.721~0.854),敏感度67.86%,特异度75.00%;在外部验证组中,AUC为0.842(95%CI:0.746~0.912),敏感度72.41%,特异度90.91%;校准曲线、DCA曲线示列线图模型的校准性能和临床适用性均较好。经病理证实/预测模型诊断的增殖型HCC患者术后无病生存期(disease free survival,DFS)均显著低于非增殖型HCC(训练组:P=0.005,P<0.001;内部验证组:P=0.006,P=0.006;外部验证组:P=0.002,P=0.015)。结论基于临床与影像特征构建的预测模型能较准确术前诊断增殖型HCC,且增殖型HCC预后较差。 展开更多
关键词 增殖型 肝细胞癌 X线计算机体层摄影术 预后研究
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基于Fréchet距离的集中式光伏场站送出线路纵联保护方法 被引量:2
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作者 王少雄 吕思辰 +6 位作者 吕飞鹏 王干尧 朱玉勇 覃渝文 廖建权 周文越 王强钢 《电网技术》 北大核心 2025年第4期1648-1657,I0068-I0074,共17页
针对传统纵联保护动作性能下降以及现有相似度保护算法存在波形差异度量不足、定值难以整定、新能源弱出力时的计算失效等问题,提出一种基于Fréchet距离的纵联保护方法。首先揭示了传统差动保护以及现有相似度算法的适应性问题。为... 针对传统纵联保护动作性能下降以及现有相似度保护算法存在波形差异度量不足、定值难以整定、新能源弱出力时的计算失效等问题,提出一种基于Fréchet距离的纵联保护方法。首先揭示了传统差动保护以及现有相似度算法的适应性问题。为此,提出一种综合考虑故障电流幅值和相位特征的保护方法。该方法将空间轨迹相似性与时域波形相关性相结合,引入Fréchet距离作为波形差异度量的量化指标,构建了Fréchet距离与时域电流波形幅、相差异之间的数学联系,为定值整定提供了理论依据。其次,结合动态规划思想优化了算法的时间复杂度。该方法不受线路电容电流、新能源出力特性的影响,相较于现有保护原理具有更优的灵敏性、可靠性。仿真结果表明,所提保护原理能准确识别区内、外故障,仅需10ms时间窗,动作速度最快可达1ms以内,具有较高耐受过渡电阻和噪音的能力。 展开更多
关键词 光伏场站 送出线路 Fréchet距离 纵联保护 故障特性
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