Einstein Probe,an astronomical satellite designed for X-ray observation on astronomical events drastically evolving over time,was successfully sent into preset orbit by a Long March 2C rocket from China’s Xichang Sat...Einstein Probe,an astronomical satellite designed for X-ray observation on astronomical events drastically evolving over time,was successfully sent into preset orbit by a Long March 2C rocket from China’s Xichang Satellite Launch Center located in Sichuan Province at 15:03 GMT+8 on January 9,2024.展开更多
The hype was flowing when 5G wireless service began rolling out around 2018(Fig.1).According to the US wireless company Verizon,based in New York City,NY,USA,5G would usher in“a Fourth Industrial Revolution”[1].The ...The hype was flowing when 5G wireless service began rolling out around 2018(Fig.1).According to the US wireless company Verizon,based in New York City,NY,USA,5G would usher in“a Fourth Industrial Revolution”[1].The technology would also allow surgeons to perform operations remotely on patients thousands of kilometers away,permit communications between driverless cars,and offer other life-changing benefits[2,3].展开更多
President Xi Jinping’s inspection tour of Hebei to promote coordinated Beijing-Tianjin-Hebei development underlines the region’s pursuit of Chinese modernization.
In recent years, a large number of approaches to constrained multi-objective optimization problems(CMOPs) have been proposed, focusing on developing tweaked strategies and techniques for handling constraints. However,...In recent years, a large number of approaches to constrained multi-objective optimization problems(CMOPs) have been proposed, focusing on developing tweaked strategies and techniques for handling constraints. However, an overly finetuned strategy or technique might overfit some problem types,resulting in a lack of versatility. In this article, we propose a generic search strategy that performs an even search in a promising region. The promising region, determined by obtained feasible non-dominated solutions, possesses two general properties.First, the constrained Pareto front(CPF) is included in the promising region. Second, as the number of feasible solutions increases or the convergence performance(i.e., approximation to the CPF) of these solutions improves, the promising region shrinks. Then we develop a new strategy named even search,which utilizes the non-dominated solutions to accelerate convergence and escape from local optima, and the feasible solutions under a constraint relaxation condition to exploit and detect feasible regions. Finally, a diversity measure is adopted to make sure that the individuals in the population evenly cover the valuable areas in the promising region. Experimental results on 45 instances from four benchmark test suites and 14 real-world CMOPs have demonstrated that searching evenly in the promising region can achieve competitive performance and excellent versatility compared to 11 most state-of-the-art methods tailored for CMOPs.展开更多
Heterodera avenae （cereal cyst nematode, CCN） infects many cereal crops and causes serious yield losses worldwide. Interaction studies investigating H. avenae and its hosts are still in their infancy. In this study,...Heterodera avenae （cereal cyst nematode, CCN） infects many cereal crops and causes serious yield losses worldwide. Interaction studies investigating H. avenae and its hosts are still in their infancy. In this study, a barley model plant, the Hordeum vulgare cultivar Golden Promise, was investigated for its potential as a candidate model host to study its inter- action with H. avenae. CCN-infective juveniles were attracted by the root tips and gathered around the root elongation zones of Golden Promise on 0.7% water agar plates. The juveniles invaded the roots and developed successfully until maturation at 40 days after inoculation in sterile sand soil. The cryotomy and syncytium measurements indicated that the syncytia enlarged gradually throughout the development of the nematodes and caused the corresponding root regions to swell obviously. Quantitative real-time PCR analysis showed that the down-regulation of defence-related barley genes and up-regulation Of development-related barley ger^es contribute to the understanding of compatible interaction between H. avenae and Golden Promise. Barley stripe mosaic virus （BSMV） virus-induced gene silencing （VIGS） can be used in the roots of Golden Promise. In conclusion, the Hordeum vulgare cultivar Golden Promise is a suitable candidate model host for interaction studies with Heterodera avenae. The studies presented above document the first CCN host that no.t only has published genome context but also be compatible to BSMV VIGS.展开更多
Despite being the long-time mainstream semiconductor for both logic and power devices, Silicon is now facing its dilemma and limitation of scalability and material potential.Especially for power devices, people are de...Despite being the long-time mainstream semiconductor for both logic and power devices, Silicon is now facing its dilemma and limitation of scalability and material potential.Especially for power devices, people are demanding escalating efficiency with higher blocking voltage while its power consumption and heat generation are less. Constrained by its narrow bandgap of 1.14 eV, Silicon only has a critical breakdown field(E_c) of 0.3 MV/cm, yielding a Baliga figureof-merit(BFOM = ε×μ× E_c^3) of unity when normalized to itself. It is hence required that the dominating factor E_c should be as high as possible such that the BFOM will be hundreds or even thousands of times when compared to Silicon so as to minimize the conduction loss. Beta-Gallium Oxide(β-Ga_2O_3) with decent μ of 250 cm2/Vs, ultra-wide bandgap of4.8 eV and high critical E_c of 8 MV/cm, yielding a superior high BFOM of more than 3000. Therefore, system made withβ-Ga_2O_3 can be thinner, lighter and capable of handling more power than the one with Silicon. In addition, low-cost and large size substrate through melt-grown method endows β-Ga_2O_3 more potentials as cost-effective power devices. After resolving the low thermal conductivity issue,unipolar devices made with ultra-wide bandgap β-Ga_2O_3 are promised to make power transition and our life more efficient.展开更多
One day in late 2022 or early 2023,a customer somewhere in the United States will make history by purchasing the first pair of hearing aids sold over the counter(OTC).For more than 40 years,these devices have been ava...One day in late 2022 or early 2023,a customer somewhere in the United States will make history by purchasing the first pair of hearing aids sold over the counter(OTC).For more than 40 years,these devices have been available in the United States and many other countries mainly through audiologists or other hearing professionals.But updated regulations scheduled for enactment later this year by the Food and Drug Administration(FDA),the US agency that oversees drugs and medical devices,will allow retailers to sell hearing aids directly to consumers[1].展开更多
Elaborate proof-of-principle experiments in several laboratories around the world have recently offered glimpses of a future in which high-throughput automatic laboratories guided by artificial intelligence(AI)might e...Elaborate proof-of-principle experiments in several laboratories around the world have recently offered glimpses of a future in which high-throughput automatic laboratories guided by artificial intelligence(AI)might enhance the process for discovery of new materials,such as those for clean energy technologies.And in chemical engineering,using AI to aid in synthesis planning and performance offers the prospect of scientists needing little more than an idea and an internet connection to generate novel molecules in state-of-the-art,remote laboratories.Announced in August 2020,International Business Machine Corporation(IBM)’s RoboRXN for Chemistry provides a high-profile example of the potential for combining AI and laboratory automation[1].The system not only provides chemical recipes to produce organic molecules of interest but can also synthesize those molecules automatically using commercially available hardware—in the case of IBM’s demonstrator,a Flex-category automated-synthesis workstation(Fig.1)manufactured by Chemspeed Technologies(Füllinsdorf,Switzerland).展开更多
Computers already gobble a large share of the world’s electrical power,and their energy demand will likely soar with the deployment of more and more power-hungry artificial intelligence(AI)systems[1].In a step that m...Computers already gobble a large share of the world’s electrical power,and their energy demand will likely soar with the deployment of more and more power-hungry artificial intelligence(AI)systems[1].In a step that might reduce AI’s electricity use and environmental impact,Lightmatter,a startup based in Boston,MA,USA,announced that it has developed a microchip that performs calculations with light and requires about one-sixth the energy of a comparable electronic chip(Fig.1)[2].Other companies are developing similar photon-based chips for AI and for many other uses,including self-driving cars and quantum computing[3,4].展开更多
目的评估中文版患者报告结局测量信息系统(Patient Reported Outcome Measurement Information System,PROMIS)癌症特异性抑郁项目库的心理测量学属性,构建计算机自适应测试版本(PROMIS Cancer Depression CAT),并评价其效果。方法采用...目的评估中文版患者报告结局测量信息系统(Patient Reported Outcome Measurement Information System,PROMIS)癌症特异性抑郁项目库的心理测量学属性,构建计算机自适应测试版本(PROMIS Cancer Depression CAT),并评价其效果。方法采用便利抽样法选取2020年11月—2021年7月在上海2所三级甲等医院的648例癌症患者作为研究对象。在心理测量学评估中,首先基于Rasch模型采用残差的主成分分析、条目残差相关系数、条目特征曲线检验PROMIS癌症特异性抑郁项目库的单维性、局部独立性、单调性假设;其次,通过Rasch模型中的选项特征曲线对选项进行拟合,采用Rasch模型中的Infit MNSQ、Outfit MNSQ、难度参数对每个条目进行拟合;最后,将经过校准后的项目库内容作为PROMIS Cancer Depression CAT的题库,采用Post-hoc模拟方法评价PROMIS Cancer Depression CAT的测量效率和准确性。结果PROMIS癌症特异性抑郁项目库由测试解释的经验方差为68.6%,条目之间的残差相关值都小于0.70,条目特征曲线是单调递增曲线。PROMIS癌症特异性抑郁项目库中的5个选项的峰值均未被相邻选项的特征曲线覆盖,5个选项之间阈值的间隔均大于1且小于5,条目的Infit MNSQ值为[0.54,1.49],Outfit MNSQ值为[0.55,1.49],选项和条目的拟合均在理想范围内,可作为构建PROMIS Cancer Depression CAT的项目库。Post-hoc模拟执行CAT的θ值与整个项目库的θ值相关系数为0.964,选择的平均使用条目数为6.348个。结论中文版PROMIS癌症特异性抑郁项目库满足单维性、局部独立性以及单调性假设,可以用来构建PROMIS Cancer Depression CAT。基于PROMIS癌症特异性抑郁项目库参数构建的计算机自适应测试版本能够高效、准确地测量癌症患者的抑郁水平。展开更多
In recent years,with the advancement of the Belt and Road Initiative,tourism cooperation has become closer between China and the countries along the Belt and Road.Statistics from the China Tourism Academy show that Ch...In recent years,with the advancement of the Belt and Road Initiative,tourism cooperation has become closer between China and the countries along the Belt and Road.Statistics from the China Tourism Academy show that China’s outbound tourists to the countries along the Belt and Road is on the rise from 15.49 million in 2013 to 27.41 million in 2017,up by 77%during five years and with an average annual growth rate of 15.34%.The development of tourism has boosted trade and cultural exchange between China and the countries along the Belt and Road,which has become a significant force in driving the construction of the Belt and Road.展开更多
文摘Einstein Probe,an astronomical satellite designed for X-ray observation on astronomical events drastically evolving over time,was successfully sent into preset orbit by a Long March 2C rocket from China’s Xichang Satellite Launch Center located in Sichuan Province at 15:03 GMT+8 on January 9,2024.
文摘The hype was flowing when 5G wireless service began rolling out around 2018(Fig.1).According to the US wireless company Verizon,based in New York City,NY,USA,5G would usher in“a Fourth Industrial Revolution”[1].The technology would also allow surgeons to perform operations remotely on patients thousands of kilometers away,permit communications between driverless cars,and offer other life-changing benefits[2,3].
文摘President Xi Jinping’s inspection tour of Hebei to promote coordinated Beijing-Tianjin-Hebei development underlines the region’s pursuit of Chinese modernization.
基金partly supported by the National Natural Science Foundation of China(62076225)。
文摘In recent years, a large number of approaches to constrained multi-objective optimization problems(CMOPs) have been proposed, focusing on developing tweaked strategies and techniques for handling constraints. However, an overly finetuned strategy or technique might overfit some problem types,resulting in a lack of versatility. In this article, we propose a generic search strategy that performs an even search in a promising region. The promising region, determined by obtained feasible non-dominated solutions, possesses two general properties.First, the constrained Pareto front(CPF) is included in the promising region. Second, as the number of feasible solutions increases or the convergence performance(i.e., approximation to the CPF) of these solutions improves, the promising region shrinks. Then we develop a new strategy named even search,which utilizes the non-dominated solutions to accelerate convergence and escape from local optima, and the feasible solutions under a constraint relaxation condition to exploit and detect feasible regions. Finally, a diversity measure is adopted to make sure that the individuals in the population evenly cover the valuable areas in the promising region. Experimental results on 45 instances from four benchmark test suites and 14 real-world CMOPs have demonstrated that searching evenly in the promising region can achieve competitive performance and excellent versatility compared to 11 most state-of-the-art methods tailored for CMOPs.
基金supported by the National Natural Science Foundation of China(31571988)the Special Fund for Agro-scientific Research in the Public Interest, China (201503114)the National Key Basic Research Program of China (973 Program, 2013CB127502)
文摘Heterodera avenae （cereal cyst nematode, CCN） infects many cereal crops and causes serious yield losses worldwide. Interaction studies investigating H. avenae and its hosts are still in their infancy. In this study, a barley model plant, the Hordeum vulgare cultivar Golden Promise, was investigated for its potential as a candidate model host to study its inter- action with H. avenae. CCN-infective juveniles were attracted by the root tips and gathered around the root elongation zones of Golden Promise on 0.7% water agar plates. The juveniles invaded the roots and developed successfully until maturation at 40 days after inoculation in sterile sand soil. The cryotomy and syncytium measurements indicated that the syncytia enlarged gradually throughout the development of the nematodes and caused the corresponding root regions to swell obviously. Quantitative real-time PCR analysis showed that the down-regulation of defence-related barley genes and up-regulation Of development-related barley ger^es contribute to the understanding of compatible interaction between H. avenae and Golden Promise. Barley stripe mosaic virus （BSMV） virus-induced gene silencing （VIGS） can be used in the roots of Golden Promise. In conclusion, the Hordeum vulgare cultivar Golden Promise is a suitable candidate model host for interaction studies with Heterodera avenae. The studies presented above document the first CCN host that no.t only has published genome context but also be compatible to BSMV VIGS.
文摘Despite being the long-time mainstream semiconductor for both logic and power devices, Silicon is now facing its dilemma and limitation of scalability and material potential.Especially for power devices, people are demanding escalating efficiency with higher blocking voltage while its power consumption and heat generation are less. Constrained by its narrow bandgap of 1.14 eV, Silicon only has a critical breakdown field(E_c) of 0.3 MV/cm, yielding a Baliga figureof-merit(BFOM = ε×μ× E_c^3) of unity when normalized to itself. It is hence required that the dominating factor E_c should be as high as possible such that the BFOM will be hundreds or even thousands of times when compared to Silicon so as to minimize the conduction loss. Beta-Gallium Oxide(β-Ga_2O_3) with decent μ of 250 cm2/Vs, ultra-wide bandgap of4.8 eV and high critical E_c of 8 MV/cm, yielding a superior high BFOM of more than 3000. Therefore, system made withβ-Ga_2O_3 can be thinner, lighter and capable of handling more power than the one with Silicon. In addition, low-cost and large size substrate through melt-grown method endows β-Ga_2O_3 more potentials as cost-effective power devices. After resolving the low thermal conductivity issue,unipolar devices made with ultra-wide bandgap β-Ga_2O_3 are promised to make power transition and our life more efficient.
文摘One day in late 2022 or early 2023,a customer somewhere in the United States will make history by purchasing the first pair of hearing aids sold over the counter(OTC).For more than 40 years,these devices have been available in the United States and many other countries mainly through audiologists or other hearing professionals.But updated regulations scheduled for enactment later this year by the Food and Drug Administration(FDA),the US agency that oversees drugs and medical devices,will allow retailers to sell hearing aids directly to consumers[1].
文摘Elaborate proof-of-principle experiments in several laboratories around the world have recently offered glimpses of a future in which high-throughput automatic laboratories guided by artificial intelligence(AI)might enhance the process for discovery of new materials,such as those for clean energy technologies.And in chemical engineering,using AI to aid in synthesis planning and performance offers the prospect of scientists needing little more than an idea and an internet connection to generate novel molecules in state-of-the-art,remote laboratories.Announced in August 2020,International Business Machine Corporation(IBM)’s RoboRXN for Chemistry provides a high-profile example of the potential for combining AI and laboratory automation[1].The system not only provides chemical recipes to produce organic molecules of interest but can also synthesize those molecules automatically using commercially available hardware—in the case of IBM’s demonstrator,a Flex-category automated-synthesis workstation(Fig.1)manufactured by Chemspeed Technologies(Füllinsdorf,Switzerland).
文摘Computers already gobble a large share of the world’s electrical power,and their energy demand will likely soar with the deployment of more and more power-hungry artificial intelligence(AI)systems[1].In a step that might reduce AI’s electricity use and environmental impact,Lightmatter,a startup based in Boston,MA,USA,announced that it has developed a microchip that performs calculations with light and requires about one-sixth the energy of a comparable electronic chip(Fig.1)[2].Other companies are developing similar photon-based chips for AI and for many other uses,including self-driving cars and quantum computing[3,4].
文摘目的评估中文版患者报告结局测量信息系统(Patient Reported Outcome Measurement Information System,PROMIS)癌症特异性抑郁项目库的心理测量学属性,构建计算机自适应测试版本(PROMIS Cancer Depression CAT),并评价其效果。方法采用便利抽样法选取2020年11月—2021年7月在上海2所三级甲等医院的648例癌症患者作为研究对象。在心理测量学评估中,首先基于Rasch模型采用残差的主成分分析、条目残差相关系数、条目特征曲线检验PROMIS癌症特异性抑郁项目库的单维性、局部独立性、单调性假设;其次,通过Rasch模型中的选项特征曲线对选项进行拟合,采用Rasch模型中的Infit MNSQ、Outfit MNSQ、难度参数对每个条目进行拟合;最后,将经过校准后的项目库内容作为PROMIS Cancer Depression CAT的题库,采用Post-hoc模拟方法评价PROMIS Cancer Depression CAT的测量效率和准确性。结果PROMIS癌症特异性抑郁项目库由测试解释的经验方差为68.6%,条目之间的残差相关值都小于0.70,条目特征曲线是单调递增曲线。PROMIS癌症特异性抑郁项目库中的5个选项的峰值均未被相邻选项的特征曲线覆盖,5个选项之间阈值的间隔均大于1且小于5,条目的Infit MNSQ值为[0.54,1.49],Outfit MNSQ值为[0.55,1.49],选项和条目的拟合均在理想范围内,可作为构建PROMIS Cancer Depression CAT的项目库。Post-hoc模拟执行CAT的θ值与整个项目库的θ值相关系数为0.964,选择的平均使用条目数为6.348个。结论中文版PROMIS癌症特异性抑郁项目库满足单维性、局部独立性以及单调性假设,可以用来构建PROMIS Cancer Depression CAT。基于PROMIS癌症特异性抑郁项目库参数构建的计算机自适应测试版本能够高效、准确地测量癌症患者的抑郁水平。
文摘In recent years,with the advancement of the Belt and Road Initiative,tourism cooperation has become closer between China and the countries along the Belt and Road.Statistics from the China Tourism Academy show that China’s outbound tourists to the countries along the Belt and Road is on the rise from 15.49 million in 2013 to 27.41 million in 2017,up by 77%during five years and with an average annual growth rate of 15.34%.The development of tourism has boosted trade and cultural exchange between China and the countries along the Belt and Road,which has become a significant force in driving the construction of the Belt and Road.
