The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell cultures.However,the lack of systematic and contin...The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell cultures.However,the lack of systematic and continuous comparison between in vivo retinal development and the organotypic retinal explant culture makes this model controversial in postnatal retinal development studies.Thus,we aimed to verify the feasibility of using this model for postnatal retinal development studies by comparing it with the in vivo retina.In this study,we showed that postnatal retinal explants undergo normal development,and exhibit a consistent structure and timeline with retinas in vivo.Initially,we used SOX2 and PAX6 immunostaining to identify retinal progenitor cells.We then examined cell proliferation and migration by immunostaining with Ki-67 and doublecortin,respectively.Ki-67-and doublecortin-positive cells decreased in both in vivo and explants during postnatal retinogenesis,and exhibited a high degree of similarity in abundance and distribution between groups.Additionally,we used Ceh-10 homeodomain-containing homolog,glutamate-ammonia ligase(glutamine synthetase),neuronal nuclei,and ionized calcium-binding adapter molecule 1 immunostaining to examine the emergence of bipolar cells,Müller glia,mature neurons,and microglia,respectively.The timing and spatial patterns of the emergence of these cell types were remarkably consistent between in vivo and explant retinas.Our study showed that the organotypic retinal explant culture model had a high degree of consistency with the progression of in vivo early postnatal retina development.The findings confirm the accuracy and credibility of this model and support its use for long-term,systematic,and continuous observation.展开更多
Nowadays, image copyright protection is one of the key points of information security in the field of education. Based on the transient property of human vision, the anti-theft and copyright protection strategies are ...Nowadays, image copyright protection is one of the key points of information security in the field of education. Based on the transient property of human vision, the anti-theft and copyright protection strategies are proposed based on the idea of animation synthesis. In this paper, experiments are designed and compared from multiple perspectives. The results show that the strategy based on animation synthesis can not only ensure the browsing effect of images, but also effectively achieve the purpose of preventing interception via screenshot and protecting the legitimate rights of the original images.展开更多
This paper investigates the dividend signaling hypothesis, described here as the relationship between dividend changes and future earnings performance. We find that managers pursue different patterns in UK from that i...This paper investigates the dividend signaling hypothesis, described here as the relationship between dividend changes and future earnings performance. We find that managers pursue different patterns in UK from that in US when making dividend policy. A positive and significant association between dividend changes and the growth of future earnings is observed in the immediately following year after dividend announced There isn＇t significant link in the longer future. These phenomena are caused by managers＇ near-eyesight in UK market. In addition, an interesting finding is that dividend decreases have larger negative influence on earnings growth than positive impact on earnings prospects of dividend increases. This is consistent with the infrequent occurrence of dividend reduction.展开更多
With the rapid increase in urban gas consumption,the frequency of maintenance and repair of gas pipelines has escalated,leading to a rise in safety accidents during these processes.The traditional manual supervision m...With the rapid increase in urban gas consumption,the frequency of maintenance and repair of gas pipelines has escalated,leading to a rise in safety accidents during these processes.The traditional manual supervision model presents challenges such as inaccurate monitoring results,incomplete risk factor analysis,and a lack of quantitative risk assessment.This research focuses on developing a dynamic risk assessment technology for gas emergency repair operations by integrating the monitoring outcomes of artificial olfactory for gas leakage information and video object recognition for visual safety factor monitoring data.To quantitatively evaluate the risk of the operation process,a three-dimensional risk assessment model combining gas leakage with riskcorrelated sensitivity was established as well as a separate three-dimensional risk assessment model integrating visual risk factors with predictable risk disposition.Furthermore,a visual risk quantification expression mode based on the risk matrix-radar map method was introduced.Additionally,a risk quantification model based on the fusion of visual and olfactory results was formulated.The verification results of simulation scenarios based on field data indicate that the visual-olfactory fusion risk assessment method can more accurately reflect the dynamic risk level of the operation process compared to simple visual safety factor monitoring.The outcomes of this research can contribute to the identification of safety status and early warning of risks related to personnel,equipment,and environmental factors in emergency repair operations.Moreover,these results can be extended to other operational scenarios,such as oil and gas production stations and long-distance pipeline operations.展开更多
The freemium pricing model has become mainstream in the software industry.A large user base can induce positive network effects while expanding security risks associated with unpatched users.This study explores a two-...The freemium pricing model has become mainstream in the software industry.A large user base can induce positive network effects while expanding security risks associated with unpatched users.This study explores a two-stage decision problem faced by software vendors that involves a freemium versioning strategy and a subsequent security-patching strategy when taking both the positive network externality and negative security externality into consideration.It is noteworthy that a joint effect of the two externalities on the vendor’s management decisions exists.First,we analytically derive three patching strategies for the vendor:PS_(1)(rebates all users),PS_(2)(rebates only freeware users),and PS_(3)(rebates no users).Our results indicate that,if the strength of the positive network externality is relatively low,the optimal security-patching strategy will be significantly affected by the negative security externality.Specifically,when the intensity of the negative security externality is low,the vendor’s optimal patching strategy will be PS_(1).However,with the increase in the negative security externality,the optimal patching strategy changes to PS_(2) and then to PS_(3),whereas the strategy spaces of PS_(1) and PS_(2) decrease in the positive network externality to zero.Nevertheless,if the strength of the positive network externality is relatively high,the vendor is better off selecting PS_(1) when the negative security externality is low.However,when the negative security externality is high,PS_(3) is optimal.Furthermore,based on optimal patching strategies,we reveal the optimal conditions required for the vendor to adopt the freemium model compared with commercial only.Of interest,we find that the vendor adopting the freemium version is also influenced by the interaction of the two externalities.Finally,through numerical experiments,we find that the vendor and social planner’s interests can be aligned under certain conditions.However,this is not always the case.展开更多
基金supported by the National Natural Science Foundation of China,Nos.81901156(to ZZ),82271200(to ZZ),82171308(to XC)the Fundamental Research Funds for the Central Universities,No.xzy012022035(to ZZ)+1 种基金the Natural Science Foundation of Shaanxi Province,Nos.2021JM-261(to QK),2023-YBSF-303(to ZZ)Traditional Chinese Medicine Project of Shaanxi Province,No.2019-ZZ-JC047(to QK)。
文摘The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell cultures.However,the lack of systematic and continuous comparison between in vivo retinal development and the organotypic retinal explant culture makes this model controversial in postnatal retinal development studies.Thus,we aimed to verify the feasibility of using this model for postnatal retinal development studies by comparing it with the in vivo retina.In this study,we showed that postnatal retinal explants undergo normal development,and exhibit a consistent structure and timeline with retinas in vivo.Initially,we used SOX2 and PAX6 immunostaining to identify retinal progenitor cells.We then examined cell proliferation and migration by immunostaining with Ki-67 and doublecortin,respectively.Ki-67-and doublecortin-positive cells decreased in both in vivo and explants during postnatal retinogenesis,and exhibited a high degree of similarity in abundance and distribution between groups.Additionally,we used Ceh-10 homeodomain-containing homolog,glutamate-ammonia ligase(glutamine synthetase),neuronal nuclei,and ionized calcium-binding adapter molecule 1 immunostaining to examine the emergence of bipolar cells,Müller glia,mature neurons,and microglia,respectively.The timing and spatial patterns of the emergence of these cell types were remarkably consistent between in vivo and explant retinas.Our study showed that the organotypic retinal explant culture model had a high degree of consistency with the progression of in vivo early postnatal retina development.The findings confirm the accuracy and credibility of this model and support its use for long-term,systematic,and continuous observation.
文摘Nowadays, image copyright protection is one of the key points of information security in the field of education. Based on the transient property of human vision, the anti-theft and copyright protection strategies are proposed based on the idea of animation synthesis. In this paper, experiments are designed and compared from multiple perspectives. The results show that the strategy based on animation synthesis can not only ensure the browsing effect of images, but also effectively achieve the purpose of preventing interception via screenshot and protecting the legitimate rights of the original images.
基金This paper is supported by National Natural Science Foundation of China （No. 7032053）, 2003 Key Research of the Humanities ＆ Social Science Program, Ministry of Education, P.R.C （No. 03JD630035）, and Education Department of Shaanxi Provice Scientific Research Program （No. 02JK011）.
文摘This paper investigates the dividend signaling hypothesis, described here as the relationship between dividend changes and future earnings performance. We find that managers pursue different patterns in UK from that in US when making dividend policy. A positive and significant association between dividend changes and the growth of future earnings is observed in the immediately following year after dividend announced There isn＇t significant link in the longer future. These phenomena are caused by managers＇ near-eyesight in UK market. In addition, an interesting finding is that dividend decreases have larger negative influence on earnings growth than positive impact on earnings prospects of dividend increases. This is consistent with the infrequent occurrence of dividend reduction.
基金This work was supported the Key Research and Development Program of Shaanxi Province[2023-YBSF-266]the China Postdoctoral Science Foundation[2021T140544].
文摘With the rapid increase in urban gas consumption,the frequency of maintenance and repair of gas pipelines has escalated,leading to a rise in safety accidents during these processes.The traditional manual supervision model presents challenges such as inaccurate monitoring results,incomplete risk factor analysis,and a lack of quantitative risk assessment.This research focuses on developing a dynamic risk assessment technology for gas emergency repair operations by integrating the monitoring outcomes of artificial olfactory for gas leakage information and video object recognition for visual safety factor monitoring data.To quantitatively evaluate the risk of the operation process,a three-dimensional risk assessment model combining gas leakage with riskcorrelated sensitivity was established as well as a separate three-dimensional risk assessment model integrating visual risk factors with predictable risk disposition.Furthermore,a visual risk quantification expression mode based on the risk matrix-radar map method was introduced.Additionally,a risk quantification model based on the fusion of visual and olfactory results was formulated.The verification results of simulation scenarios based on field data indicate that the visual-olfactory fusion risk assessment method can more accurately reflect the dynamic risk level of the operation process compared to simple visual safety factor monitoring.The outcomes of this research can contribute to the identification of safety status and early warning of risks related to personnel,equipment,and environmental factors in emergency repair operations.Moreover,these results can be extended to other operational scenarios,such as oil and gas production stations and long-distance pipeline operations.
文摘The freemium pricing model has become mainstream in the software industry.A large user base can induce positive network effects while expanding security risks associated with unpatched users.This study explores a two-stage decision problem faced by software vendors that involves a freemium versioning strategy and a subsequent security-patching strategy when taking both the positive network externality and negative security externality into consideration.It is noteworthy that a joint effect of the two externalities on the vendor’s management decisions exists.First,we analytically derive three patching strategies for the vendor:PS_(1)(rebates all users),PS_(2)(rebates only freeware users),and PS_(3)(rebates no users).Our results indicate that,if the strength of the positive network externality is relatively low,the optimal security-patching strategy will be significantly affected by the negative security externality.Specifically,when the intensity of the negative security externality is low,the vendor’s optimal patching strategy will be PS_(1).However,with the increase in the negative security externality,the optimal patching strategy changes to PS_(2) and then to PS_(3),whereas the strategy spaces of PS_(1) and PS_(2) decrease in the positive network externality to zero.Nevertheless,if the strength of the positive network externality is relatively high,the vendor is better off selecting PS_(1) when the negative security externality is low.However,when the negative security externality is high,PS_(3) is optimal.Furthermore,based on optimal patching strategies,we reveal the optimal conditions required for the vendor to adopt the freemium model compared with commercial only.Of interest,we find that the vendor adopting the freemium version is also influenced by the interaction of the two externalities.Finally,through numerical experiments,we find that the vendor and social planner’s interests can be aligned under certain conditions.However,this is not always the case.
