During sexual reproduction of seaweeds, spermatozoid (sperm) discharge is triggered by chemical messengers (pheromones) released by the female gametes. The chemotactic ability of the sperm ensures fertilization succes...During sexual reproduction of seaweeds, spermatozoid (sperm) discharge is triggered by chemical messengers (pheromones) released by the female gametes. The chemotactic ability of the sperm ensures fertilization success. Using unialgal male and female gametophyte material under designated standard gametogenesis testing (SGT) conditions, the potential life-span of the sperm of two seaweeds, Saccharina japonica and Undaria pinnatifida, was assessed by their ability to fertilize eggs. Results show that within 20-30 min after being discharged, sperm of both species could complete fertilization without an apparent decline in fertilization rate. Although fertilization rate 60-120 min after sperm discharge dropped significantly in both species, some sperm were viable enough to fertilize the eggs. In S.japonica, at 12°C, some sperm were able to fertilize eggs up to 12 h after discharge. In both species, egg discharge rates (EDR) in the male and female mixed positive controls were significantly higher than those of all the sperm-testing groups. Doubling the seeded male gametophytes of S. japonica in the SGT tests significantly increased the EDR, further confirming the effect of the presence of the male on the female in terms of facilitating egg discharge from oogonia.展开更多
The paper concerns Cauchy,problem for one-dimensional hydromagnetic dynamics with dissipative terms. When the dissipation coefficient is equal to zero it is shown that the smooth solutions develop shocks in the finite...The paper concerns Cauchy,problem for one-dimensional hydromagnetic dynamics with dissipative terms. When the dissipation coefficient is equal to zero it is shown that the smooth solutions develop shocks in the finite time if the initial amounts of entropy and magnetic field are smaller than those of sound waves; when it is larger than zero, and the initial amounts of entropyI this dissipation coefficient and the magnetic field in each period are smaller than those of sound Waves, then the smooth solutions blow up in the finite time. Moreover, the life-span of the smooth solution is given.展开更多
In this article, we investigate the lower bound of life-span of classical solutions of the hyperbolic geometry flow equations in several space dimensions with ＂small＂ initial data. We first present some estimates on...In this article, we investigate the lower bound of life-span of classical solutions of the hyperbolic geometry flow equations in several space dimensions with ＂small＂ initial data. We first present some estimates on solutions of linear wave equations in several space variables. Then, we derive a lower bound of the life-span of the classical solutions to the equations with ＂small＂ initial data.展开更多
For solving the dilemma of the short exothermic life-span of WO_(3)based metastable interstitial composites(MICs)with extensive application prospect,this paper has firstly designed the promising antiwetting Al/WO_(3)M...For solving the dilemma of the short exothermic life-span of WO_(3)based metastable interstitial composites(MICs)with extensive application prospect,this paper has firstly designed the promising antiwetting Al/WO_(3)MICs via electrophoresis assembly of nano-Al and WO_(3)particles fabricated by hydrothermal synthesis method,followed by the subsequent fluorination treatment.A combination of X ray diffraction(XRD),field emission scanning electron microscope(FESEM),energy dispersive X-ray spectroscopy(EDX),and Fourier transform infrared spectroscopy(FT-IR)techniques were utilized in order to characterize the crystal structure,microstructure,and elemental composition distribution of target films after different natural exposure tests.The product with uniform distribution and high purity possesses a high contact angle of~170°and a minute sliding angle of~1°,and displays the outstanding anti-wetting property using droplets with different surface tensions.It also shows great moisture stability in high relative-humidity circumstances after one year of the natural exposure experiment.Notably,the heat output of a fresh sample can reach up to 2.3 kJ/g and retain 96%after the whole exposure test,showing outstanding thermo-stability for at least one year.This work further proposed the mechanism of antiwetting Al/WO_(3)MICs considering the variation tendency of their DSC curve,providing a valuable theoretical reference for designing other self-protected MICs with a long exothermic life-span applied in wide fields of national defense,military industry,etc.展开更多
Products with long life-spans are generally acknowledged to have a significant contribution towards sustainability. This paper provides an overview and discussion of the two years results of a longitudinal study perfo...Products with long life-spans are generally acknowledged to have a significant contribution towards sustainability. This paper provides an overview and discussion of the two years results of a longitudinal study performed with users and several cork products. The research aimed to tackle the process of life-span, and the results include： （1） the identification and interrelation of the aspects influencing the life-span of the products; （2） the evolution of life-span over time; and （3） new knowledge and guidelines arising about the material. Overall, most cork products are still being used, have a very good life-span, and most issues arising are material related.展开更多
Objective： To explore the effects and mechanisms of flavonoids from Scutellaria baicalensis Georgi in hydrogenperoxide （H2O2） induced Drosophila melanogaster model. Method： H2O2 induced Drosophila melanogaster agi...Objective： To explore the effects and mechanisms of flavonoids from Scutellaria baicalensis Georgi in hydrogenperoxide （H2O2） induced Drosophila melanogaster model. Method： H2O2 induced Drosophila melanogaster agingmodel was used to study the effects of flavonoids from Scutellaria baicalensis Georgi. Secondly, the effects ofbaicalein and wogonin on mRNA expressions were examined. Results： Our results found that baicalein andwogonin could extend the life-spans of H2O2 induced Drosophila melanogaster aging model via increased mRNAexpressions of superoxide dismutase catalase and rosy. Conclusion： Baicalein and wogonin could extend life-spansof H2O2 induced Drosophila melanogaster aging model through increasing mRNA expressions of superoxidedismutase, catalase and rosy.展开更多
The author considers the life-span of classical solutions to Cauchy problem for general first order quasilinear strictly hyperbolic systems in two independent variables with "slow" decay initial data. By con...The author considers the life-span of classical solutions to Cauchy problem for general first order quasilinear strictly hyperbolic systems in two independent variables with "slow" decay initial data. By constructing an example, first it is illustrated that the classical solution to this kind of Cauchy problem may blow up in a finite time, even if the system is weakly linearly degenerate. Then some lower bounds of the life-span of classical solutions are given in the case that the system is weakly linearly degenerate. These estimates imply that, when the system is weakly linearly degenerate, the classical solution exists almost globally in time. Finally, it is proved that Theorems 1.1-1.3 in [2] are still valid for this kind of initial data.展开更多
This article investigates the blow-up results for the initial boundary value problem to the quasi-linear parabolic equation with p-Laplacian■where p≥2 and the function f(u)satisfies■for some positive constantsα,β...This article investigates the blow-up results for the initial boundary value problem to the quasi-linear parabolic equation with p-Laplacian■where p≥2 and the function f(u)satisfies■for some positive constantsα,β,γwith 0<■,which has been studied under the initial condition Jp(u0)<0.This paper generalizes the above results on the following aspects:a new blow-up condition is given,which holds for all p>2;a new blow-up condition is given,which holds for p=2;some new lifespans and upper blow-up rates are given under certain conditions.展开更多
This paper is concerned with the Cauchy problem for a semilinear wave equation with a time-dependent damping.In case that the space dimension n=1 and the nonlinear power is bigger than 2,the life-span T(ε)and global ...This paper is concerned with the Cauchy problem for a semilinear wave equation with a time-dependent damping.In case that the space dimension n=1 and the nonlinear power is bigger than 2,the life-span T(ε)and global existence of the classical solution to the problem has been investigated in a unified way.More precisely,with respect to different values of an index K,which depends on the time-dependent damping and the nonlinear term,the life-span T(ε)can be estimated below byε-p/1-k,e^(ε)-p or+∞,where e is the scale of the compact support of the initial data.展开更多
In this paper, we consider the mixed initial-boundary value problem for quasilinear hyperbolic systems with nonlinear boundary conditions in a half-unbounded domain {（t, x）｜t ≥ 0, x ≥ 0}. Under the assumption tha...In this paper, we consider the mixed initial-boundary value problem for quasilinear hyperbolic systems with nonlinear boundary conditions in a half-unbounded domain {（t, x）｜t ≥ 0, x ≥ 0}. Under the assumption that the positive eigenvalues are not all weakly linearly degenerate,we obtain the blow-up phenomenon of the first order derivatives of C^1 solution with small and decaying initial data.We also give precise estimate of the life-span of C^1 solution.展开更多
The author considers the life-span of classical solutions to Cauchy problem for general first order quasilinear strictly hyperbolic systems in two independent variables with "slow" decay initial data. By con...The author considers the life-span of classical solutions to Cauchy problem for general first order quasilinear strictly hyperbolic systems in two independent variables with "slow" decay initial data. By constructing an example, first it is illustrated that the classical solution to this kind of Cauchy problem may blow up in a finite time, even if the system is weakly linearly degenerate. Then some lower bounds of the life-span of classical solutions are given in the case that the system is weakly linearly degenerate. These estimates imply that, when the system is weakly linearly degenerate, the classical solution exists almost globally in time. Finally, it is proved that Theorems 1.1-1.3 in [2] are still valid for this kind of initial data.展开更多
The reconstructive process in memory may cause distortions or errors.Associative memory illusion is one of the most common types of false memories.It acts as a reflection of the adaptive characteristic of memory by su...The reconstructive process in memory may cause distortions or errors.Associative memory illusion is one of the most common types of false memories.It acts as a reflection of the adaptive characteristic of memory by suggesting its ability to adaptively use semantic gist information even with limited cognitive resources.Meanwhile, the adaptive characteristic of memory is also manifested by inhibiting false memories with certain strategies (e.g., encoding item-specific information) to ensure memory accuracy according to the demands of specific situations.This article looks into the life-span developmental features of the adaptive characteristic of memory by summarizing the age features of two types of abilities: employing gist representation and inhibiting associative memory illusion.In the future, further efforts in this field are proposed to explore the specific adaptive nature of memory from the perspective of evolution.展开更多
【目的】选育能够适应猫胃肠环境且具有良好肠道定殖能力的猫源青春双歧杆菌菌株。【方法】从长寿猫和普通猫的粪便中分离出青春双歧杆菌,通过生长量测试和小鼠寿命试验选育得到原始菌株QC-Y(寿命延长率达33.85%),经鉴定该菌为青春双歧...【目的】选育能够适应猫胃肠环境且具有良好肠道定殖能力的猫源青春双歧杆菌菌株。【方法】从长寿猫和普通猫的粪便中分离出青春双歧杆菌,通过生长量测试和小鼠寿命试验选育得到原始菌株QC-Y(寿命延长率达33.85%),经鉴定该菌为青春双歧杆菌。QC-Y经辐射诱变后,通过生长量测试、胃肠耐受性驯化和评价选育得到QC-Y-09。【结果】QC-Y-09的生长量、耐受性评分分别是QC-Y的55.667倍和5.66倍,其对猫胃肠环境的耐受能力具有良好的遗传稳定性。第10代QC-Y-09菌株在人工胃液、肠液、无氧和微氧环境中的存活率分别为18.80%、41.60%、93.26%和48.39%,分别达到0代的62.67%、108.53%、97.92%和94.40%。猫肠道定殖试验表明,QC-Y-09在猫体内的定殖能力显著优于QC-Y和人源青春双歧杆菌。停止饲喂菌剂7 d后,QC-Y-09组猫粪便中青春双歧杆菌活菌仍有4.37 lg CFU/g,分别比QC-Y组和人源组高1.74 lg CFU/g和3.02 lg CFU/g。此外,QC-Y-09对猫换粮应激具有较好的缓解作用,能降低猫换粮应激率85.71%。SNP分析结果表明QC-Y-09在基因层面与QC-Y有显著差异,主要富集在核糖体结构和氨基酰基-tRNA生物合成的通路上。【结论】本研究选育的猫源青春双歧杆菌QC-Y-09菌株能够有效适应猫胃肠环境并在猫肠道中良好定殖,这为青春双歧杆菌在猫用功能性食品中的应用提供了重要的理论和实践基础。展开更多
基金Supported by National High Technology Research and Development Program of China (863 Program)(No.2012AA10A413)the National Natural Science Foundation of China (Nos.41206146,41176135,41206142)+3 种基金the National Special Research Fund for Non-Profit Sector (Agriculture) from the Ministry of Agriculture (No.200903030)the Knowledge Innovation Program of Chinese Academy of Sciences (No.KSCX2-EW-B-3)the National Key Basic Program of Science and Technology-Platforms of Aquaculture Stock Resourcesthe Leading Academic Discipline Project of the Shanghai Municipal Education Commission (No.J50701)
文摘During sexual reproduction of seaweeds, spermatozoid (sperm) discharge is triggered by chemical messengers (pheromones) released by the female gametes. The chemotactic ability of the sperm ensures fertilization success. Using unialgal male and female gametophyte material under designated standard gametogenesis testing (SGT) conditions, the potential life-span of the sperm of two seaweeds, Saccharina japonica and Undaria pinnatifida, was assessed by their ability to fertilize eggs. Results show that within 20-30 min after being discharged, sperm of both species could complete fertilization without an apparent decline in fertilization rate. Although fertilization rate 60-120 min after sperm discharge dropped significantly in both species, some sperm were viable enough to fertilize the eggs. In S.japonica, at 12°C, some sperm were able to fertilize eggs up to 12 h after discharge. In both species, egg discharge rates (EDR) in the male and female mixed positive controls were significantly higher than those of all the sperm-testing groups. Doubling the seeded male gametophytes of S. japonica in the SGT tests significantly increased the EDR, further confirming the effect of the presence of the male on the female in terms of facilitating egg discharge from oogonia.
基金Project supported by the National Natural Science Foundation of China(No. 10571024)the Natural Science Foundation of Henan Province of China (No.200510078005)the Science Foundation of Educational Department of Henan Province of China (No.200511051700)
文摘The paper concerns Cauchy,problem for one-dimensional hydromagnetic dynamics with dissipative terms. When the dissipation coefficient is equal to zero it is shown that the smooth solutions develop shocks in the finite time if the initial amounts of entropy and magnetic field are smaller than those of sound waves; when it is larger than zero, and the initial amounts of entropyI this dissipation coefficient and the magnetic field in each period are smaller than those of sound Waves, then the smooth solutions blow up in the finite time. Moreover, the life-span of the smooth solution is given.
基金supported in part by the NNSF of China(11271323,91330105)the Zhejiang Provincial Natural Science Foundation of China(LZ13A010002)the Henan Provincial Natural Science Foundation of China(152300410226)
文摘In this article, we investigate the lower bound of life-span of classical solutions of the hyperbolic geometry flow equations in several space dimensions with ＂small＂ initial data. We first present some estimates on solutions of linear wave equations in several space variables. Then, we derive a lower bound of the life-span of the classical solutions to the equations with ＂small＂ initial data.
基金funded by the financial support from National Natural Science Foundation of China(Grant No 21805014 and No82102635)Science and Technology Research Project of Chongqing Education Board(Grant No.KJQN201901428)。
文摘For solving the dilemma of the short exothermic life-span of WO_(3)based metastable interstitial composites(MICs)with extensive application prospect,this paper has firstly designed the promising antiwetting Al/WO_(3)MICs via electrophoresis assembly of nano-Al and WO_(3)particles fabricated by hydrothermal synthesis method,followed by the subsequent fluorination treatment.A combination of X ray diffraction(XRD),field emission scanning electron microscope(FESEM),energy dispersive X-ray spectroscopy(EDX),and Fourier transform infrared spectroscopy(FT-IR)techniques were utilized in order to characterize the crystal structure,microstructure,and elemental composition distribution of target films after different natural exposure tests.The product with uniform distribution and high purity possesses a high contact angle of~170°and a minute sliding angle of~1°,and displays the outstanding anti-wetting property using droplets with different surface tensions.It also shows great moisture stability in high relative-humidity circumstances after one year of the natural exposure experiment.Notably,the heat output of a fresh sample can reach up to 2.3 kJ/g and retain 96%after the whole exposure test,showing outstanding thermo-stability for at least one year.This work further proposed the mechanism of antiwetting Al/WO_(3)MICs considering the variation tendency of their DSC curve,providing a valuable theoretical reference for designing other self-protected MICs with a long exothermic life-span applied in wide fields of national defense,military industry,etc.
文摘Products with long life-spans are generally acknowledged to have a significant contribution towards sustainability. This paper provides an overview and discussion of the two years results of a longitudinal study performed with users and several cork products. The research aimed to tackle the process of life-span, and the results include： （1） the identification and interrelation of the aspects influencing the life-span of the products; （2） the evolution of life-span over time; and （3） new knowledge and guidelines arising about the material. Overall, most cork products are still being used, have a very good life-span, and most issues arising are material related.
基金This project was supported by the National Natural Science Foundation of China （81603319）, and partlysupported by Programs of Science and Technology and Higher Education of Shanxi Province （2015118）, Scienceand Technology Innovation Team of Shanxi Province （201605D131045-18）, and Key laboratory of EffectiveSubstances Research and Utilization in TCM of Shanxi province （201605D111004）.
文摘Objective： To explore the effects and mechanisms of flavonoids from Scutellaria baicalensis Georgi in hydrogenperoxide （H2O2） induced Drosophila melanogaster model. Method： H2O2 induced Drosophila melanogaster agingmodel was used to study the effects of flavonoids from Scutellaria baicalensis Georgi. Secondly, the effects ofbaicalein and wogonin on mRNA expressions were examined. Results： Our results found that baicalein andwogonin could extend the life-spans of H2O2 induced Drosophila melanogaster aging model via increased mRNAexpressions of superoxide dismutase catalase and rosy. Conclusion： Baicalein and wogonin could extend life-spansof H2O2 induced Drosophila melanogaster aging model through increasing mRNA expressions of superoxidedismutase, catalase and rosy.
基金Project supported by the National Natural Science Foundation of China
文摘The author considers the life-span of classical solutions to Cauchy problem for general first order quasilinear strictly hyperbolic systems in two independent variables with "slow" decay initial data. By constructing an example, first it is illustrated that the classical solution to this kind of Cauchy problem may blow up in a finite time, even if the system is weakly linearly degenerate. Then some lower bounds of the life-span of classical solutions are given in the case that the system is weakly linearly degenerate. These estimates imply that, when the system is weakly linearly degenerate, the classical solution exists almost globally in time. Finally, it is proved that Theorems 1.1-1.3 in [2] are still valid for this kind of initial data.
基金Supported by the Doctoral Scientific Research Starting Foundation of Guizhou Normal University of China,2018(No.GZNUD[2018]34 and 11904/0519113).
文摘This article investigates the blow-up results for the initial boundary value problem to the quasi-linear parabolic equation with p-Laplacian■where p≥2 and the function f(u)satisfies■for some positive constantsα,β,γwith 0<■,which has been studied under the initial condition Jp(u0)<0.This paper generalizes the above results on the following aspects:a new blow-up condition is given,which holds for all p>2;a new blow-up condition is given,which holds for p=2;some new lifespans and upper blow-up rates are given under certain conditions.
基金supported by the NSF of China(11731007)the Priority Academic Program Development of Jiangsu Higher Education Institutions,and the NSF of Jiangsu Province(BK20181381,BK20221320).
文摘This paper is concerned with the Cauchy problem for a semilinear wave equation with a time-dependent damping.In case that the space dimension n=1 and the nonlinear power is bigger than 2,the life-span T(ε)and global existence of the classical solution to the problem has been investigated in a unified way.More precisely,with respect to different values of an index K,which depends on the time-dependent damping and the nonlinear term,the life-span T(ε)can be estimated below byε-p/1-k,e^(ε)-p or+∞,where e is the scale of the compact support of the initial data.
基金This project supported by National Natural Science Foundation of China （10371099）.
文摘In this paper, we consider the mixed initial-boundary value problem for quasilinear hyperbolic systems with nonlinear boundary conditions in a half-unbounded domain {（t, x）｜t ≥ 0, x ≥ 0}. Under the assumption that the positive eigenvalues are not all weakly linearly degenerate,we obtain the blow-up phenomenon of the first order derivatives of C^1 solution with small and decaying initial data.We also give precise estimate of the life-span of C^1 solution.
基金Project supported by the National Natural Science Foundation of China
文摘The author considers the life-span of classical solutions to Cauchy problem for general first order quasilinear strictly hyperbolic systems in two independent variables with "slow" decay initial data. By constructing an example, first it is illustrated that the classical solution to this kind of Cauchy problem may blow up in a finite time, even if the system is weakly linearly degenerate. Then some lower bounds of the life-span of classical solutions are given in the case that the system is weakly linearly degenerate. These estimates imply that, when the system is weakly linearly degenerate, the classical solution exists almost globally in time. Finally, it is proved that Theorems 1.1-1.3 in [2] are still valid for this kind of initial data.
基金supported by the National Natural Science Foundation of China (30870763)Beijing Natural Science Foundation (7093123)the Major Philosophical and Social Program of Ministry of Education of China (06JZD0039)
文摘The reconstructive process in memory may cause distortions or errors.Associative memory illusion is one of the most common types of false memories.It acts as a reflection of the adaptive characteristic of memory by suggesting its ability to adaptively use semantic gist information even with limited cognitive resources.Meanwhile, the adaptive characteristic of memory is also manifested by inhibiting false memories with certain strategies (e.g., encoding item-specific information) to ensure memory accuracy according to the demands of specific situations.This article looks into the life-span developmental features of the adaptive characteristic of memory by summarizing the age features of two types of abilities: employing gist representation and inhibiting associative memory illusion.In the future, further efforts in this field are proposed to explore the specific adaptive nature of memory from the perspective of evolution.
文摘【目的】选育能够适应猫胃肠环境且具有良好肠道定殖能力的猫源青春双歧杆菌菌株。【方法】从长寿猫和普通猫的粪便中分离出青春双歧杆菌,通过生长量测试和小鼠寿命试验选育得到原始菌株QC-Y(寿命延长率达33.85%),经鉴定该菌为青春双歧杆菌。QC-Y经辐射诱变后,通过生长量测试、胃肠耐受性驯化和评价选育得到QC-Y-09。【结果】QC-Y-09的生长量、耐受性评分分别是QC-Y的55.667倍和5.66倍,其对猫胃肠环境的耐受能力具有良好的遗传稳定性。第10代QC-Y-09菌株在人工胃液、肠液、无氧和微氧环境中的存活率分别为18.80%、41.60%、93.26%和48.39%,分别达到0代的62.67%、108.53%、97.92%和94.40%。猫肠道定殖试验表明,QC-Y-09在猫体内的定殖能力显著优于QC-Y和人源青春双歧杆菌。停止饲喂菌剂7 d后,QC-Y-09组猫粪便中青春双歧杆菌活菌仍有4.37 lg CFU/g,分别比QC-Y组和人源组高1.74 lg CFU/g和3.02 lg CFU/g。此外,QC-Y-09对猫换粮应激具有较好的缓解作用,能降低猫换粮应激率85.71%。SNP分析结果表明QC-Y-09在基因层面与QC-Y有显著差异,主要富集在核糖体结构和氨基酰基-tRNA生物合成的通路上。【结论】本研究选育的猫源青春双歧杆菌QC-Y-09菌株能够有效适应猫胃肠环境并在猫肠道中良好定殖,这为青春双歧杆菌在猫用功能性食品中的应用提供了重要的理论和实践基础。
