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Age-specific mortality and fecundity of a spider mite under diet restriction and delayed mating

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Insect Science 2022年第3期29卷 889-899页

作者： Guang-Yun Li Zhi-qiang ZHANG Centre for Biodiversity and Biosecurity School of Biological SciencesUniversity of AucklandAucklandNew Zealand Manaaki Whenua-Landcare Research AucklandNew Zealand Key Laboratory of Entomology and Pest Control Engineering College of Plant ProtectionSouthwest UniversityChongqingChina

Numerous experimental life-history studies on aging are mainly baised on two classical models—fruit fly Drosophila melanogaster(Meigen)and nematode Caenorhab-ditis elegans(Maupas)—with relatively little attention given to other organisms with different life-history characters.Two-spotted spider mite Tetranychus urticae Koch(Acari:Tetranychidae)differs from many other arthropods in that the females continue their growth in the early adult stage and can reproduce sexually and asexually.In this study,the influences of dietary restriction and delayed mating on the aging patterns of the spider mite were examined with the prevailing survival and reproduction trade-off hypothesis of aging being tested.Significant sex-specific responses of the spider mites were found.The females showed longevity extension on diet restriction(fasting for 2 days in every 4 days)compared with their counterparts being fed ad libitum,and after delayed mating for 9 days,while the males displayed a decrease in lifespan when experiencing diet restriction but were not significantly influenced by delayed mating.Path analysis was used to investigate the relationship between mite survival and reproduction traits,including longevity,female lifetime reproduction,age at first reproduction,early reproductive efforts and late reproductive efforts,yielding no evidence for trade-offs between these life-history traits.The additive effects of dietary restriction and delayed mating in lifespan extension of female spider mites were confirmed,proving that diet restriction is a robust anti-aging intervention,and that later onset of reproduction can prolong adult lifespan in females.

关键词： age-specific mortality delayed mating diet restriction reproduction sex difference trade-off

Prey life stages modulate effects of predation stress on prey lifespan,development,and reproduction in mites

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Insect Science 2023年第3期30卷 844-856页

作者： Xiaoying Weil Guangyun Li Zhi-qiang ZHANG School of Biological Sciences The University of AucklandAucklandNew Zealand Key Laboratory of Entomology and Pest Control Engineering College of Plant ProtectionSouthwest UniversityChongqingChina Manaaki Whenua-Landcare Research AucklandNewZealand

The non-consumptive effects of predator-induced stress can influence a variety of life-history traits.Many previous studies focused only on short-term effects such as development and reproductive rates.Recent studies have showed that long-term predation stress(given during the whole life of the prey)and short-term predation stress(provided during the immature stage of the prey)could generate completely opposite results:the former could decrease lifespan,whereas the later could increase lifespan.However,it is still unclear whether the advantage is because of the short duration of exposure or the early stage of life during which exposure was exerted.Thus,in this study,the prey(Tyrophagus putrescentiae)was exposed to predation stress from the predator(Neoseiulus cucumeris)during different life stages(larva,protonymph,tritonymph,first 5 d of oviposition,the full lifespan or none of the above).The results showed that the predation stress supplied during larval and protonymphal stage delayed development,reduced fecundity and prolonged lifespan of the prey,while the stress given during tritonymphal stage only reduced lifespan slightly and the stress given during the first 5 d of oviposition did not change lifespan but reduced fecundity.This study indicated that the effects of predation stress are dependent on prey life stage and the predation stress experienced in the early life stages is important to lifespan modulation.

关键词： early life experience lifespan non-consumptive effects predation stress tyrophagus

Model test of the mechanism underpinning water-and-mud inrush disasters during tunnel excavation in sandstone and slate interbedded Presinian strata

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第11期23卷 882-899页

作者： Peng XU Peng PENG Rong-hua WEI Zhi-qiang ZHANG School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China

Water-and-mud inrush disasters have become a major challenge in underground engineering for the construction of tunnels in sandstone and slate interbedded Presinian strata.Disaster prediction and prevention rely in part on realistic modeling and observation of the disaster process,as well as the identification and examination of the underlying mechanisms.Based on the geological conditions and the historical records of the Xinping Tunnel on the China–Laos Railway,an engineering geological model of the water-and-mud inrush was established.A physical model test that accurately reproduced water-and-mud inrush during tunnel excavation in sandstone and slate interbedded strata was also carried out.Then,testing was conducted that examined the stress and strain,seepage pressure,and high-leakage flow of the surrounding rock.The results indicated that the water-and-mud inrush proceeded through three stages:seepage stage,high-leakage flow stage,and attenuation stage.In essence,the disaster was a catastrophic process,during which the water-resistant stratum was reduced to a critical safety thickness,a water-inrush channel formed,and the water-resistant stratum gradually failed under the influence of excavation unloading and in situ stress–seepage coupling.Parameters such as the stress and strain,seepage pressure,and flow of the surrounding rock had evident stage-related features during water-and-mud inrush,and their variation indicated the formation,development,and evolution of the disaster.As the tunnel face advanced,the trend of the stress–strain curve of the surrounding rock shifted from sluggish to rapid in its speed of increase.The characteristics of strain energy density revealed the erosion and weakening effect of groundwater on the surrounding rock.The seepage pressure and the thickness of the water-resistant stratum had a positive linear relationship,and the flow and thickness a negative linear relationship.There was a pivotal point at which the seepage pressure changed from high to low and the flow shifted from low

关键词： Water-and-mud inrush Sandstone and slate interbedded Presinian strata Model test Evolution law Thickness of water-resistant stratum Inducing mechanism

Harmful evaluation of heavy metals from soil layer to the groundwater: Take the Jilin Hunchun Basin as an example

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China Geology 2024年第1期7卷 116-124页

作者： Xiao-Dong Guo qiang Liu Hui-Rong zhang Xu-Fei Shi Chuan-Yu Qin Zhi-qiang ZHANG Shenyang Geological Survey Center China Geological SurveyMinistry of Natural ResourcesShenyang 110034China Key Laboratory of Black Land Evolution and Ecological Effects Shenyang 110034China New Energy and Environment College Jilin UniversityChangchun 130026China Jilin Hydrogeological Survey Institute Changchun 130026China

The continuous enrichment of heavy metals in soils has caused potential harm to groundwater.Quantitative methods to evaluate the harm of heavy metals in soil to groundwater are lacked in previous studies.Based on the theory of groundwater circulation and solid-liquid equilibrium,a simple and easy-touse flux model of soil heavy metals migrating to groundwater is constructed.Based on groundwater environmental capacity,an innovative method for evaluating the harm of heavy metals in soil to groundwater is proposed,which has been applied in Hunchun Basin,Jilin Province,China.The results show that the fluxes of soil heavy metals into groundwater in the study area are Zn,Cu,As,Pb,Cd,Ni,and Hg in descending order.The content of heavy metals in groundwater(As,Hg,Cu,Pb,Zn,Ni,and Cd)in most areas has not risen to the threshold of environmental capacity within 10 years.The harm levels of soil heavy metals to groundwater in the most townships soils are at the moderate level or below.This evaluation method can quantify the flux of soil heavy metals into groundwater simply and quickly,determine the residual capacity of groundwater to heavy metals,evaluate the harm level of soil heavy metals to groundwater,provide support for relevant departments to carry out environmental protection of soil and groundwater,and provide a reference to carry out similar studies for related scholars.

关键词： Soil heavy metals As+Hg+Cu+Pb+Zn+Ni+Cd Environmental capacity Groundwater Hazard degree Migration flux model Agricultural geological survey engineering Hunchun Basin Jilin Province

简谐与光晶格复合势阱中旋转二维玻色-爱因斯坦凝聚体中的涡旋链

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物理学报 2022年第22期71卷 47-57页

作者：张志强郑州商学院通识教育中心郑州451200

利用数值计算方法,研究了由简谐势与光晶格势构成的复合势阱中旋转二维玻色-爱因斯坦凝聚体中涡旋的产生、涡旋链的形成,以及涡旋链的特性.首先利用多重网格预条件共轭梯度法,研究了二维凝聚体中涡旋的产生、涡旋链的形成及分布情况和... 详细信息

利用数值计算方法,研究了由简谐势与光晶格势构成的复合势阱中旋转二维玻色-爱因斯坦凝聚体中涡旋的产生、涡旋链的形成,以及涡旋链的特性.首先利用多重网格预条件共轭梯度法,研究了二维凝聚体中涡旋的产生、涡旋链的形成及分布情况和不同物理参量对涡旋链的影响;其次利用时间分裂谱方法研究了涡旋链随时间的演化情况.结果表明,囚禁于复合势阱的凝聚体中涡旋的产生,对应于势阱的极小值,当光晶格深度增大到一定值时,凝聚体中形成了涡旋链,而随着光晶格深度的进一步增大,凝聚体中涡旋链中的涡旋深度不断减小,最终涡旋链完全消失.当原子间相互作用强度增大,凝聚体的分布范围扩大,凝聚体中的涡旋和涡旋链的数量也增加,但当原子间相互作用强度增大一定值后,涡旋链的对称性被破坏.随着凝聚体旋转角速度的增大,凝聚体的分布范围随之扩展,凝聚体中涡旋和涡旋链的数量也随之增加.当凝聚体旋转角速度接近外部势阱的谐振频率时,涡旋链的直线排列被破坏.还发现凝聚体中涡旋链随时间演化存在3个阶段:第1阶段涡旋链与凝聚体一同旋转且保持原有的链状分布不变;第2阶段出现了涡旋空间挤压现象,涡旋链被破坏;第3阶段出现了涡旋空间扩张现象,最终涡旋链消失.

关键词：波色-爱因斯坦凝聚涡旋链光晶格复合势阱

Localization of normalized solutions for saturable nonlinear Schr?dinger equations

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Science China Mathematics 2023年第11期66卷 2495-2522页

作者： Xiaoming Wang zhi-qiang Wang Xu zhang School of Mathematics&Computer Science Shangrao Normal UniversityShangrao 334001China College of Mathematics and Statistics Fujian Normal UniversityFuzhou 350117China Department of Mathematics and Statistics Utah State UniversityLoganUT 84322USA School of Mathematics and Statistics Central South UniversityChangsha 410083China

In this paper,we study the existence and concentration behavior of the semiclassical states with L2-constraints for the following saturable nonlinear Schr?dinger equation:-ε2Δv+Γ(I(x)+v^(2))/(1+I(x)+v^(2))v=λv for x∈R2.For a negatively large coupling constantΓ,we show that there exists a family of normalized positive solutions(i.e.,with the L2-constraint)whenεis small,which concentrate around local maxima of the intensity function I(x)asε→0.We also consider the case where I(x)may tend to-1 at infinity and the existence of multiple solutions.The proof of our results is variational and the novelty of the work lies in the development of a new truncation-type method for the construction of the desired solutions.

关键词： saturable nonlinear Schrodinger equation normalized solutions semiclassical states local maximum potential

Cell number explains the intraspecific spur-length variation in an Aquilegia species

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Plant Diversity 2019年第5期41卷 307-314页

作者： zhi-Li Zhou Yuan-Wen Duan Yan Luo Yong-Ping Yang Zhi-qiang ZHANG Institute of Tibetan Plateau Research at Kunming Kunming Institute of BotanyChinese Academy of SciencesKunming650201China University of Chinese Academy of Sciences Beijing 100049China Gardening and Horticulture Department Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla666303China Laboratory of Ecology and Evolutionary Biology Yunnan UniversityKunming650091China

Variations of nectar spur length allow pollinators to utilize resources in novel ways,leading to the different selective pressures on spurs and allowing taxa to diversify.However,the mechanisms underlying spur length variation remain unclear.Interspecific comparisons of spur length suggest that both cell division and anisotropic expansion could explain the changes of spur length,and that hormone-related genes contribute to the process of spur formation.In contrast,little is known about intraspecific spur length variation.In Aquilegia rockii,spur length varies strikingly,ranging from 1 mm to 18 mm.To examine the potential mechanisms underlying spur length variation in A.rockii,we observed cell morphology and analyzed RNA-seq of short-and long-spurred flowers.Scanning electron microscopy revealed that at two positions on spurs there were no differences in either cell density or cell anisotropy between short-and long-spurred flowers,suggesting that in A.rockii changes in cell number may explain variations in spur length.In addition,we screened transcriptomes of short-and long-spurred flowers for differentially expressed genes;this screen identified several genes linked to cell division(e.g.,F-box,CDKB2-2,and LST8),a finding which is consistent with our analysis of the cellular morphology of spurs.However,we did not find any highly expressed genes involved in the hormone pathway in long-spurred flowers.In contrast to previous hypotheses that anisotropic cell expansion leads to interspecific spur variation in Aquilegia,our results suggest that cell number changes and related genes are mainly responsible for spur length variations of A.rockii.Furthermore,the underlying mechanisms of similar floral traits in morphology may be quite different,enriching our understanding of the mechanisms of flower diversity in angiosperms.

关键词： Aquilegia rockii Cell number Columbine Floral polymorphism Intraspecific variation Nectar spur

Uncertainty and sensitivity analysis of in-vessel phenomena under severe accident mitigation strategy based on ISAA-SAUP program

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Nuclear Science and Techniques 2024年第1期35卷 108-123页

作者： Hao Yang Ji-Shen Li zhi-Ran zhang Bin zhang Jian-qiang Shan School of Nuclear Science and Technology Xi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an 710049China

The phenomenology involved in severe accidents in nuclear reactors is highly complex.Currently,integrated analysis programs used for severe accident analysis heavily rely on custom empirical parameters,which introduce considerable uncertainty.Therefore,in recent years,the field of severe accidents has shifted its focus toward applying uncertainty analysis methods to quantify uncertainty in safety assessment programs,known as“best estimate plus uncertainty(BEPU).”This approach aids in enhancing our comprehension of these programs and their further development and improvement.This study concentrates on a third-generation pressurized water reactor equipped with advanced active and passive mitigation strategies.Through an Integrated Severe Accident Analysis Program(ISAA),numerical modeling and uncertainty analysis were conducted on severe accidents resulting from large break loss of coolant accidents.Seventeen uncertainty parameters of the ISAA program were meticulously screened.Using Wilks'formula,the developed uncertainty program code,SAUP,was employed to carry out Latin hypercube sampling,while ISAA was employed to execute batch calculations.Statistical analysis was then conducted on two figures of merit,namely hydrogen generation and the release of fission products within the pressure vessel.Uncertainty calculations revealed that hydrogen production and the fraction of fission product released exhibited a normal distribution,ranging from 182.784 to 330.664 kg and from 15.6 to 84.3%,respectively.The ratio of hydrogen production to reactor thermal power fell within the range of 0.0578–0.105.A sensitivity analysis was performed for uncertain input parameters,revealing significant correlations between the failure temperature of the cladding oxide layer,maximum melt flow rate,size of the particulate debris,and porosity of the debris with both hydrogen generation and the release of fission products.

关键词： Gen-III PWR Severe accident mitigation Wilks’formula Hydrogen Fission products Uncertainty and sensitivity analysis

Sub-additive Unstable Topological Pressure of Diffeomorphisms

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Acta Mathematica Sinica,English Series 2022年第12期38卷 2285-2298页

作者： Wen Da zhang zhi qiang LI Yun Hua ZHOU College of Mathematics and Statistics Chongqing Jiaotong UniversityChongqing 400074P.R.China College of Mathematics and Statistics Chongqing UniversityChongqing 401331P.R.China

In this paper,we study unstable topological pressure for C^(1)-smooth partially hyperbolic diffeomorphisms with sub-additive potentials.Moreover,without any additional assumption,we have established the expected variational principle which connects this unstable topological pressure and the unstable measure theoretic entropy,as well as the corresponding Lyapunov exponent.

关键词： Partially hyperbolic systems unstable topological pressure sub-additive potentials