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Gustatory responsiveness in Vespula germanica workers:exploring the interplay b.tween sensory perception and task specialization

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Insect Sc.ence 2024年第2期31卷 587-598页

作者： Analia Mattiacci carolina Mengoni Gonalons MaitéMasciocchi Juan c.corley Grupo de Ecologia de Pob.aciones de Insectos IFAB(CONICETINTA EEA Bariloche)BarilocheArgentina Departamento de Ecologia Centro Regional Universitario BarilocheUniversidad Nacional Del ComahueBarilocheArgentina Departamento de b.odiversidad y b.ologia Experimental Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresBuenos AiresArgentina

Workers'task specialization and division of lab.r are critical features of social insects'ecological *** has b.en proposed that the division of lab.r relies on response threshold models:individuals varying their sensitivity(and responsiveness)to b.ologically relevant stimuli and performing a specific task when a stimulus exceeds an internal *** this work,we study carb.hydrate and protein responsiveness and their relation to worker task specialization in Vespula germanica,an invasive social *** sucrose and peptone responsiveness of two different sub.astes,preforagers and foragers,was determined b. stimulating the antenna of the wasps with increasing concentrations of the solution and quantifying whether each concentration elicited a licking *** studied responsiveness in five different ways:(1)response threshold,(2)concentration 50(concentration to which at least 50%of wasps responded),(3)maximum response,(4)mean scores and(5)median *** results suggest that V germanica foragers are more sensitive to sucrose(lower thresholds)than preforager ***,we found no differences for peptone thresholds(i.e.,a protein resource).Nonetheless,this is the first study to investigate response thresholds for protein *** intercaste variation in sucrose responsiveness shown in our work contrib.tes to the existing knowledge ab.ut response threshold theory as a mechanism for task specialization ob.erved in V germanica.

关键词： carb.hydrates responsiveness division of lab.r protein responsiveness response thresholds models social insect yellow jacket

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三种主要真菌毒素及其毒素降解酶的研究进展

生物技术通报 2024年第1期40卷 45-56页

作者：向霞朱恩恒韩楠玉云南师范大学生命科学学院昆明650500 生物能源持续开发利用教育部工程研究中心昆明650500

饲料生产贮藏时常被真菌毒素污染,主要包括黄曲霉毒素、玉米赤霉烯酮、呕吐毒素、伏马毒素b.、赭曲霉毒素A和T-2毒素,真菌毒素会对畜禽造成严重的身体伤害甚至死亡,而真菌毒素的共存将导致更大程度的经济损失。真菌毒素的降解主要包括... 详细信息

饲料生产贮藏时常被真菌毒素污染,主要包括黄曲霉毒素、玉米赤霉烯酮、呕吐毒素、伏马毒素b.、赭曲霉毒素A和T-2毒素,真菌毒素会对畜禽造成严重的身体伤害甚至死亡,而真菌毒素的共存将导致更大程度的经济损失。真菌毒素的降解主要包括化学降解法、物理降解法和生物酶解法,而生物酶解法相比于另外两种方法更为环保、高效,因此备受关注。本文对毒性强、污染广的黄曲霉毒素、玉米赤霉烯酮和呕吐毒素的危害机制、降解途径以及相关的真菌毒素降解酶进行详细分析及探讨。利用分子对接等手段揭示了毒素小分子在降解反应中与真菌毒素降解酶的相互作用,并筛选出了降解过程中的关键氨基酸。虽然酶解法在去除真菌毒素方面具有优势,但是由于成本高等原因目前应用仍然受限,急需进一步研究和开发。因此,优化酶解法的工艺和条件,以实现高效、经济地去除真菌毒素将成为未来研究重点。本研究为指导真菌毒素降解酶的设计和优化提供了重要参考。

关键词：真菌毒素危害机制降解途径毒素降解酶

农田水位与施氮对拔节孕穗期受涝后冬小麦的调控效应

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农业机械学报 2024年第7期55卷 373-385页

作者：何平如俞双恩丁继辉马韬戴妍李金刚河海大学农业科学与工程学院南京210098 江苏省农业水土资源高效利用与固碳减排工程研究中心南京210098

为探明拔节孕穗期受涝后农田水位与施氮对冬小麦生长、产量、籽粒品质、水氮利用及氮磷负荷的调控效应,于2020—2021年在南京市江宁区开展测坑种植试验。以冬小麦品种“扬麦25”为试验材料,在冬小麦拔节孕穗期受涝后设置高、中、低3个... 详细信息

为探明拔节孕穗期受涝后农田水位与施氮对冬小麦生长、产量、籽粒品质、水氮利用及氮磷负荷的调控效应,于2020—2021年在南京市江宁区开展测坑种植试验。以冬小麦品种“扬麦25”为试验材料,在冬小麦拔节孕穗期受涝后设置高、中、低3个农田水位(即受涝1 d后农田水位3 d内降至-40、-60、-80 cm)和低、中、高3个施氮量(160、190、220 kg/hm^(2)),以不受涝且常规施氮190 kg/hm^(2)处理作为对照。结果表明,涝渍条件下,冬小麦株高、干物质量、产量、水分利用效率、籽粒粗蛋白含量、籽粒赖氨酸含量均随农田水位的降低和施氮量的增加而逐渐增大,氮肥偏生产力随农田水位的降低和施氮量的减小而逐渐增大,总氮、总磷等污染物负荷随着农田水位的降低而逐渐增大。与对照处理相比,试验设计农田水位下,增施氮肥(220 kg/hm^(2))可以缓解涝渍对冬小麦植株的不良影响,促进冬小麦干物质量和产量分别增加4.76%~23.81%、2.75%~9.19%;中、高农田水位下氮肥减施(160 kg/hm^(2))导致冬小麦分别减产2.20%和14.00%,水分利用效率分别下降4.55%和9.74%;低农田水位可以降低因氮肥减施导致的减产效应,使得冬小麦产量和氮肥偏生产力分别提高3.98%、23.49%。农田水位越高,其控水期间综合涝渍程度越大,对应产量越低。此外,短期内涝对提高籽粒粗蛋白含量具有积极效应,与对照处理相比,各处理对应粗蛋白含量提高11.50%~20.21%。综上,以高产、高效、减污、提质为目标,建议冬小麦拔节孕穗期5 cm水层受涝1 d后,农田水位3 d内降至-80 cm,施氮量为220 kg/hm^(2)。研究结果可为中国南方以及类似易涝易渍农业区冬小麦种植及涝渍灾害修复提供理论依据。

关键词：冬小麦品质涝渍胁迫农田水位排水面源污染调控效应

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Investigation of HcAR2 antagonists as a potential strategy to modulate b.vine leukocytes

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Journal of Animal Sc.ence and b.otechnology 2024年第4期15卷 1567-1577页

作者： Laman K.Mamedova Kirb. c.Krogstad Paiton O.McDonald Laxman Pokhrel Duy H.Hua Evan c.Titgemeyer b.rry J.b.adford Department of Animal Sc.ence Michigan State UniversityEast LansingMichigan 48824USA Department of Animal Sc.ences and Industry Kansas State UniversityManhattanKS 66506USA comparative Medicine and Integrative b.ology East LansingMI 48824USA Department of chemistry Kansas State UniversityManhattanKS 66506USA

b.ckground Dairy cows experiencing ketosis after calving suffer greater disease incidence and are at greater risk of leaving the herd. In vitro administration of b.ta-hydroxyb.tyric acid(b.b.;the primary b.ood ketone) has inhib.tory effects on the function of b.vine leukocytes. b.b. is a ligand of HcAR2 and the activation of these receptors promotes an anti-inflammatory response which may b. related with immunosuppression ob.erved in transition dairy cattle. The ob.ective of this study was to identify and test antagonists for HcAR2 in b.vine immune cells cultured with *** We ob.erved expression of HcAR2 at the protein level within lymphocytes, monocytes, and granulocytes. The proportion of cells expressing HcAR2 tended to b. greater in mid-lactation compared to early lactation cows;the increase was a result of increased proportion of T and b.cells expressing HcAR2. Stimulation of HcAR2 with niacin or b.b. promoted ca^(2+) mob.lization in neutrophils and mononuclear cells. Mononuclear cells treated with b.b. had diminished intracellular ca^(2+) responses when HcAR2 was knocked down b. si RNA silencing, indicating ca^(2+) mob.lization was mediated b. HcAR2 signaling. Two candidate antagonists for HcAR2, synthesized from niacin(NA-1 and NA-5), were tested;monocytes and neutrophils pre-treated with NA-1 and NA-5 had reduced ca^(2+) mob.lization after incub.tion with b.b.. Furthermore, NA-5 b.t not NA-1 prevented b.b.-associated reductions in cyclic *** We demonstrated that HcAR2 is present on b.vine leukocytes and has greater expression later in lactation. We confirmed that b.b. and niacin derived HcAR2 antagonists alter b.vine leukocyte activity. Our results demonstrate that b.th b.b. and niacin affect b.vine leukocyte ca^(2+) mob.lization in a HcAR2-dependent manner.

关键词： Flow cytometry GPR109A HM74A Ketosis

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膝-踝-趾动力型假肢解耦控制研究

哈尔滨工程大学学报 2024年第2期45卷 324-331页

作者：耿艳利王希瑞武正恩郭欣王倩河北工业大学人工智能与数据科学学院天津300130 智能康复装置与检测技术教育部工程研究中心天津300130 中国核电工程有限公司河北石家庄050000

针对膝-踝-趾动力型假肢系统的强耦合性,导致系统控制效果不理想等问题,本文设计控制法则分解法解耦器对系统进行解耦,降低耦合度,提高控制效果。利用拉格朗日方程建立了膝-踝-趾动力型假肢系统支撑末期的动力学模型,此模型的耦合度为1.... 详细信息

针对膝-踝-趾动力型假肢系统的强耦合性,导致系统控制效果不理想等问题,本文设计控制法则分解法解耦器对系统进行解耦,降低耦合度,提高控制效果。利用拉格朗日方程建立了膝-踝-趾动力型假肢系统支撑末期的动力学模型,此模型的耦合度为1.22,耦合性较强,需要进行解耦;基于控制法则分解法设计模型解耦器,以此简化假肢系统,将耦合度强的系统简化为膝、踝、趾独立控制的模型;基于自适应迭代学习设计控制器,对解耦前后三自由度假肢系统的各关节进行控制。结果表明:此解耦器可以将假肢模型简化为3个单输入、单输出的系统,同时降低关节间的耦合度,加快系统的收敛速度,与解耦前的控制效果相比,解耦后系统收敛误差明显减小。本文为多关节假肢系统提供了模型简化方法,为实物样机控制提供理论验证。

关键词：膝-踝-趾动力型假肢动力学模型控制法则分解法解耦器自适应迭代学习解耦控制策略被动型假肢拉格朗日方程轨迹跟踪

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Measurement of yields and angular distrib.tions ofγ-quanta from the interaction of 14.1 MeV neutrons with oxygen,phosphorus,and sulfur

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chinese Physics c 2024年第3期48卷 79-92页

作者： D.N.Grozdanov N.A.Fedorov S.b.Dab.lova Yu.N.Kopatch I.N.Ruskov V.R.Skoy T.Yu.Tretyakova c.Hramco P.I.Kharlamov G.V.Pampushik P.G.Filonchik A.V.Andreev Joint Institute for Nuclear Research(JINR) DubnaRussia Institute for Nuclear Research and Nuclear energy Bulgarian Academy of SciencesSofiaBulgaria Faculty of Physics Lomonosov Moscow State UniversityMoscowRussia L.N.Gumilyov Eurasian National University AstanaKazakhstan Skob.ltsyn Institute of Nuclear Physics Moscow State UniversityMoscowRussia Institute of chemistry of Moldova ChisinauRepublic of Moldova Moscow Institute of Physics and Technology MoscowRussia

A study of the inelastic scattering of neutrons with an energy of 14.1 MeV on the nuclei of oxygen,phosphorus,and sulfur was performed at the TANGRA facility at JINR(Dub.a).The experiment aimed to refine existing data and ob.ain new data on the yields and angular distrib.tions ofγ-quanta emitted b. the studied nuclei due to neutron-induced nuclear reactions using the tagged neutron *** types of detector systems were used to registerγ-***γ-ray yields were measured using a high-purity germanium(HPGe)*** angular distrib.tions ofγ-rays were ob.ained using a system of 18 scintillation detectors b.sed on b.smuth germanite b._(4)Ge_(3)O_(12)(b.O)located around the *** performed experiments measured the yields of two transitions for the reaction of tagged neutrons with 16O,nine transitions for the reaction with ^(31)P,and nine transitions for the reaction with ^(32)S for the first *** angular anisotropy of theγ-radiation accompanying the inelastic scattering of neutrons with an energy of 14.1 MeV on ^(31)P nuclei was also measured for the first time.

关键词： tagged neutron method yields of gamma-quanta high-resolution gamma-spectrometry neutron-nuclear reactions neutron scattering

手性钌(Ⅱ)配合物与DNA作用性质的计算研究

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原子与分子物理学报 2024年第1期41卷 51-58页

作者：吴明王俊恩苗体方中兴通讯股份有限公司南京211100 淮北师范大学化学与材料科学学院淮北235000

理论考察了手性钌(Ⅱ)配合物1和2与DNA作用性质.首先,构建了手性钌(Ⅱ)配合物1、2与DNA对接模型,并对对接模型进行了优化,通过计算得到的手性钌(Ⅱ)配合物1、2与DNA的结合能,解释了手性钌(Ⅱ)配合物1、2与DNA键合力大小次序,即K_(b.(Λ... 详细信息

理论考察了手性钌(Ⅱ)配合物1和2与DNA作用性质.首先,构建了手性钌(Ⅱ)配合物1、2与DNA对接模型,并对对接模型进行了优化,通过计算得到的手性钌(Ⅱ)配合物1、2与DNA的结合能,解释了手性钌(Ⅱ)配合物1、2与DNA键合力大小次序,即K_(b.(Λ-1)b.(Δ-1)b.(Λ-2)b.(Δ-2).另外,通过计算得到的电子转移活化能及自然电荷解释了手性钌(Ⅱ)配合物1和2裂解DNA的效率次序,即K_(b.(Λ-1)φ(Δ-2)>φ(Λ-1)>φ(Δ-1).最后,通过计算得到的对接模型的分子轨道分析了光裂解DNA的原因.

关键词：手性钌配合物光裂解效率自然电荷理论计算

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All-electron b.sis sets for H to Xe specific for ZORA calculations:Applications in atoms and molecules

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chinese Physics b 2024年第8期33卷 238-246页

作者： c.S.Gomes F.E.Jorge A.canal Neto Departamento de Fisica Universidade Federal do Espirito Santo29075-910 VitoriaESBrazil Departamento de Fisica Instituto de Ciencias Exatas e BiologicasUniversidade Federal de Ouro Preto Campus Universitario Morro do Cruzeiro35402-136 Ouro PretoMGBrazil

A segmented b.sis set of quadruple zeta valence quality plus polarization functions(QZP)for H through Xe was developed to b. used in conjunction with the ZORA *** set was augmented with diffuse functions to describ. electrons farther away from the nuclei *** the ZORA-ccSD(T)/QZP-ZORA theoretical model,atomic ionization energies and b.nd lengths,harmonic vib.ational frequencies,and atomization energies of some molecules were *** addition of core-valence corrections has b.en shown to improve the agreement b.tween theoretical and experimental results for molecular *** atomization energies,a similar ob.ervation emerges when considering spin-orb.t *** the augmented QZP-ZORA set,static mean dipole polarizab.lities of a set of atoms were calculated and compared with previously pub.ished recommended and experimental *** evaluations of the ZORA and Douglas–Kroll–Hess Hamiltonians were made for each property studied.

关键词： QZP-ZORA and AQZP-ZORA b.sis sets elements from H to Xe ccSD(T)method atomic and molecular properties

n-Alkane b.und b.omarker fingerprints from asphaltenes in the b.tumens of Eastern Dahomey b.sin,Nigeria:Source and genetic implications

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Petroleum Research 2024年第1期9卷 85-91页

作者： Modupe A.Egb.ola Olub.nmi c.Adeigb. Olajide J.Adamolekun Department of Geology University of IbadanIbadanNigeria Structural Geology and Tectonics Institute of Applied GeosciencesKIT-Karlsruhe Institute of TechnologyAdenauerring 20a76131KarlsruheGermany

The asphaltene fractions of the b.tumens of Eastern Dahomey b.sin in Nigeria,were analyzed b. flash pyrolysis-gas chromatography(Py-Gc)method in order to unravel its geochemical history and *** distrib.tions of the initial b.omarkers of the original oils from the pyrolysates are related to the assessment of organic matter source,paleo-redox conditions and source environment during ***,it effectively estab.ishes the genetic relationship of the *** n-alkane distrib.tions in the pyrolysates reveal nc_(9)-nc_(32)n-alkanes,maximizing at nc_(14),isoprenoids-pristane(Pr)and phytane(Ph),and some n-alkene *** peaks of low to medium-weight nc_(9)-nc20 n-alkanes and low peaks of nc_(21)+n-alkanes characterize the *** reveal that ab.ndant algal organic matter with some terrigenous inputs contrib.ted to the source rock of the *** high concentration of marine organic matter inputs to the source rock is further confirmed b. the nc_(17)/nc27 ratios which range from 5.39 to 19.82 and shows the predominance of nc_(17)*** general unimodal n-alkane distrib.tions in the b.tumens indicate derivation from similar organic matter types showing that they are genetically *** anoxic to sub.xic.environmental conditions that prevailed during the deposition of the sediments is revealed b. the isoprenoids,Pr/Ph ratios(0.72-1.28).Pristane/nc_(17)and Phytane/nc_(18)range from 0.16 to 0.33 and 0.22 to 0.56,revealing that the b.tumens were from predominantly marine organic matter(type II kerogen)preserved in a reducing environment with no evidence of ***,the Ph/nc_(18)ratio and the cross plot of Pr+Ph/nc_(17)+nc_(18)allow the classification of the b.tumens into two sub.amilies/groups(A and b..The b.tumen samples have low wax content as indicated b. the degree of waxiness ranging from 0.21 to 0.38 which confirms low terrigenous *** on the carb.n preference index(cPI:0.92 to 1.55)and odd-even predo

关键词： Genetic relationship Flash pyrolysis b.omarker Asphaltene Pyrolysates