目的分析非离子型碘造影剂致患者死亡的特点和影响因素,并提出安全用药建议,为临床用药提供参考。方法检索中国知网、万方医学、维普网、PubMed、Cochrane Library、Web of Science、Embase、SpringerLink数据库,收集非离子型碘造影剂...目的分析非离子型碘造影剂致患者死亡的特点和影响因素,并提出安全用药建议,为临床用药提供参考。方法检索中国知网、万方医学、维普网、PubMed、Cochrane Library、Web of Science、Embase、SpringerLink数据库,收集非离子型碘造影剂致患者死亡的病例报道,统计并分析其致患者死亡的特点和影响因素。结果共检索到非离子型碘造影剂致患者死亡43例,男性21例(48.84%)、女性22例(51.16%);死亡患者的年龄以51~85岁(32例,占74.42%)为主,原患疾病以心脑血管疾病(30.23%)和消化系统疾病(30.23%)居多;仅2例患者有明确的过敏史(4.65%);致死药物中,碘海醇(37.21%)和碘普罗胺(25.58%)占比最高,主要致死原因为过敏性休克(51.16%)、心脏骤停(11.63%)及肺水肿(11.63%);48.84%患者的药物不良反应(ADR)发生在30 min内,62.79%的患者在发生ADR当天死亡;主要累及循环系统、神经系统和呼吸系统,表现主要为呼吸困难、血压偏低或测不到、呕吐等。结论非离子型碘造影剂致死药物以碘海醇和碘普罗胺为主,其不良反应发生速度快。临床需重点监测患者使用该类药物后30 min内的生命体征,及时处理呼吸困难、血压异常等症状,以降低患者死亡风险。展开更多
Acetol is a major light oxygenate and readily produced from staged or fast pyrolysis of lignocellulose biomass. Herein we report that acetol can be selectively converted to methyl pyruvate, an important fine chemical,...Acetol is a major light oxygenate and readily produced from staged or fast pyrolysis of lignocellulose biomass. Herein we report that acetol can be selectively converted to methyl pyruvate, an important fine chemical, through oxidative esterification over Au-based catalysts. Detailed experimental studies showed that Au on amphoteric supports with appropriate strength and balanced ratio of acid and base sites can facilitate the desired oxidative-esterification pathway without accelerating undesired aldol-condensation or Cannizzaro reactions. In particular, hydroxyapatite (with a Ca/P ratio of 1.62) supported Au achieved 87% selectivity to methyl pyruvate at an acetol conversion of 62%.展开更多
Under the background of competency-based transformation of higher education,bioengineering major urgently needs to solve the problems such as the disconnect between practical teaching and industry needs and the lack o...Under the background of competency-based transformation of higher education,bioengineering major urgently needs to solve the problems such as the disconnect between practical teaching and industry needs and the lack of resources.This paper proposed supplementing traditional experimental teaching with video resources to construct a closed-loop model of"theoretical instruction,case analysis,video demonstration,and reflective application".Through the development of instructional videos covering core techniques such as PCR,Western blot,CRISPR-Cas9,cell culture,HPLC,GMP operations,and bioinformatics analysis,teaching costs can be reduced,spatiotemporal constraints can be overcome,and process visualization can be enhanced,thereby supporting students in mastering the entire workflow of modern biomanufacturing.The paper further explored resource development pathways,university-enterprise collaboration mechanisms,and curriculum integration strategies,offering actionable solutions for practical teaching reform.展开更多
The rapid advancement of the bioeconomy imposes increasingly stringent demands on bioengineering education.Drawing on data from the 2025 Chinese Undergraduate Employment Report and related sources,this study revealed ...The rapid advancement of the bioeconomy imposes increasingly stringent demands on bioengineering education.Drawing on data from the 2025 Chinese Undergraduate Employment Report and related sources,this study revealed that while employment placement rates for bioengineering graduates remain stable,starting salaries exhibit limited growth and career trajectories lack clarity.These challenges originate from a curriculum lagging behind technological progress,inadequate practical training,and a mismatch between student competencies and industry expectations.To address these issues,this paper proposed a strategic framework grounded in"demand-driven design,industry-education integration,and competence-centered development".Key strategies include dynamic curriculum renewal,collaborative university-industry training,holistic competency development,and personalized student support,which collectively aim at enhancing graduates employment competitiveness and long-term professional sustainability.展开更多
Gene Engineering Principles is a fundamental professional course for majors such as bioengineering and biotechnology.It integrates theoretical knowledge with experimental practice and engineering applications.It is ch...Gene Engineering Principles is a fundamental professional course for majors such as bioengineering and biotechnology.It integrates theoretical knowledge with experimental practice and engineering applications.It is characterized by its comprehensive and highly practical nature.Aligning with the new-era higher education philosophy of‘competency-oriented,value-driven’teaching,this study presented a systematic exploration and practice based on undergraduate cohorts from 2018 to 2020 in Chengdu University.The reform focused on teaching methodology,formative assessment,and the integration of ideological and political education.Key strategies included the introduction of classical experimental cases,emphasis on pre-class preparation,enhancement of classroom interaction,focus on engineering-oriented applications,optimization of assessment mechanisms,and the incorporation of national strategic needs into the curriculum.These measures effectively stimulated students’learning motivation and research potential,thereby improving the overall teaching quality and educational effectiveness of the course.The results of the teaching reform demonstrate significant improvements in students’ability to apply theoretical knowledge to practical engineering problems,scientific thinking,experimental research skills,scientific reasoning,and professional identity.Reformed classes outperformed control groups across various instructional metrics,achieving notable educational outcomes.展开更多
The intriguing catalytic performance of non-metallic nitrogen-doped carbon materials in the oxygen reduction reaction(ORR) has garnered considerable interest in elucidating their active site structure.The existing stu...The intriguing catalytic performance of non-metallic nitrogen-doped carbon materials in the oxygen reduction reaction(ORR) has garnered considerable interest in elucidating their active site structure.The existing studies,however,present conflicting conclusions regarding the contributions of various N species to ORR activity.In this work,we designed and synthesized a series of molecules featuring well-defined structures and single N species,such as pyridinic N,graphitic N+(positively charged),and pyrrolic N,to serve as model catalysts.This approach aimed to eliminate the interference caused by the coexistence of multiple N species within carbon network,thereby providing a more precise understanding of their individual contributions to ORR activity.Our experimental results revealed that pyridinic N elevated onset potential,and graphitic N+enhanced current density in ORR.Both pyridinic N and graphitic N+can promote the transition of the ORR process from the 2e^(-) to the 4e^(-).Theoretical calculations further indicated that neutral graphitic N is more active than graphitic N+.Additionally,dynamic interconversion between graphitic N and graphitic N+(e.g.,via [4+1]e^(-),[2+1]e^(-),or [4-1]e^(-) pathways) during catalysis may adversely affect the intrinsic activity of graphitic N in practical applications.These findings provide insights into mechanism understanding in depth and design guidance for carbonbased catalysts for ORR.展开更多
The heavy-atom effect of halogen(Br and I)has been widely employed for boosting spin-crossover in organic molecules,while recent investigation indicated halogen-substitution can also enhance fluorescence and even lead...The heavy-atom effect of halogen(Br and I)has been widely employed for boosting spin-crossover in organic molecules,while recent investigation indicated halogen-substitution can also enhance fluorescence and even lead to aggregation-induced emission(AIE).In this work,we investigated ultrafast excited state dynamics of a halogen-substituted model system,i.e.squaryliums NSQ-R(R=H,Cl,Br,I),by using femtosecond spectroscopy and theoretical approach.Fast external reorganization(Ex-re,~3 ps)and slow internal reorganization(In-re,5-20 ps)were observed,while quantitative fitting indicated halogen-substitution leads to a slower non-radiative S1→S0 decay(k_(NR)^(s))and subsequently enhanced fluorescence emitting.By analyzing the extracted k_(NR)^(s)within theoretical framework of non-radiative transition in the strong coupling regime,a plausible AIE mechanism of NSQs was revealed.Our work provides a clear picture on non-radiative dynamics of halogen-substituted squaryliums,which might be useful for future development of organic dyes.展开更多
Under the background of the continuous deepening of engineering education accreditation and the construction of emerging engineering disciplines,a digital platform-assisted teaching model was explored for the teaching...Under the background of the continuous deepening of engineering education accreditation and the construction of emerging engineering disciplines,a digital platform-assisted teaching model was explored for the teaching reform of the molecular biology course to effectively support the achievement of graduation requirements for bioengineering major and enhance the teaching outcomes of the molecular biology course.The teaching reform of this course took the 2022 cohort students majoring in bioengineering in Chengdu University as the practice object.The course evaluation method was improved by integrating digital platforms for process assessment,and real-world research and practical cases were incorporated into digital platforms to enrich teaching resources.Additionally,digital platforms were integrated throughout the entire teaching process(before,during,and after class),reshaping the instructional workflow into"pre-class online self-learning,in-class teacher-student interaction for deepening knowledge internalization,and practical case studies during and after class for strengthening application".The teaching reform results demonstrated that this teaching model significantly improved the attainment of course objectives,providing valuable experience for similar institutions to advance digital course reforms under the framework of engineering education accreditation.展开更多
Exploring the phenotypic trait variation and diversity of kiwifruit male plant resources can support selection,breeding,and genetic improvement,ultimately enhancing agricultural production.In this study,50 kiwifruit m...Exploring the phenotypic trait variation and diversity of kiwifruit male plant resources can support selection,breeding,and genetic improvement,ultimately enhancing agricultural production.In this study,50 kiwifruit male plants were collected from the resource nursery of Sichuan Provincial Natural Resources Bureau.The phenotypic variation of the germplasm was analyzed using 16 quantitative traits.The analysis involved coefficient of variation(CV),Shannon-Wiener index(H),principal component analysis,correlation analysis,cluster analysis,and comprehensive evaluation.The results showed that the variation range of 16 phenotypic traits in kiwifruit male germplasm resources was 1.55%to 83.71%,with an average coefficient of variation of 28.62%,and an H index of 1.265 to 2.941.The average CVs of diploid,tetraploid,and hexaploid were 22.62%,18.99%and 18.18%,respectively,and the average CV of diploid was the largest.Indicated that the male germplasm resources of kiwifruit showed significant phenotypic diversity,and the diploid showed higher diversity characteristics.Principal component analysis(PCA)revealed that the cumulative variance contribution rate of the first seven principal components was 76.66%,which effectively captured the information from 21 traits.Cluster analysis divided the 50 kiwifruit male germplasm resources into 4 clusters;each cluster exhibited distinct phenotypic characteristics.The analysis also determined the trait characteristics and breeding value of each cluster.The results of this study provide valuable information for genetic improvement,protection,and evaluation of kiwifruit male germplasm resources.展开更多
The performance of cesium lead halide per-ovskite devices is seriously affected by grain boundaries and other charge traps in the poly-crystalline perovskite thin films.LiBr doping could effectively passivate defects ...The performance of cesium lead halide per-ovskite devices is seriously affected by grain boundaries and other charge traps in the poly-crystalline perovskite thin films.LiBr doping could effectively passivate defects in CsPbBr_(3) perovskite thin films,but it is still unclear that whether the passivation can help the carriers to diffuse across the grain boundaries.Here we have studied the carrier recombina-tion and diffusion dynamics in LiBr passivat-ed CsPbBr_(3) perovskite film with poly(9-vinyl-carbazole)(PVK)film underneath by using ultrafast transient absorption spectroscopy and transient absorption microscopy.The photoluminescence imaging and transient absorption morphological imaging show that LiBr passivating has made the grain size larger and reduced grain boundaries in CsPbBr_(3) film.The transient absorption spectroscopy and time-re-solved photoluminescence data indicate that LiBr passivating has slowed down the bimolecu-lar recombination rate and extended the carrier lifetime.The photoexcited hot holes in the perovskite layer would transfer to the PVK layer in the initial 2 ps.And the transient absorp-tion microscopy measurements reveal that the LiBr passivation can help the carriers to diffuse across the grain boundaries to the surrounding grains in the CsPbBr_(3) perovskite films.The carrier diffusion time is around 100 ps when the distance between two grains is~0.9μm.展开更多
The gold nano-plates(Au NPLs)have been extensively studied for their high quality factor as mechanical resonators.But it remains still unclear how the thickness and morphology of Au NPLs affect the hot electron diffus...The gold nano-plates(Au NPLs)have been extensively studied for their high quality factor as mechanical resonators.But it remains still unclear how the thickness and morphology of Au NPLs affect the hot electron diffusion.Here we have employed transient absorption microscopy to gain spatiotemporal imaging of the hot electron diffusion in Au NPLs.Au NPLs of varying thickness over 200 nm were synthesized.It was found that the hot electron diffusion of Au NPL excited at the boundary is obviously faster than that excited at the internal surface.And thinner Au NPLs exhibit a faster hot electron diffusion rate compared to thicker Au NPLs.Because the time constant of hot electron cooling(electron-phonon coupling)is independent of the excited position and thickness of Au NPLs,the effect of electron-phonon coupling on hot electron diffusion should be ruled out.So the hot electron diffusion rate is highly dimensionality-dependent.The quasi-one-dimensional diffusion along the boundary of nanoplate has the fastest rate of 50 cm^(2)/s,and the three-dimensional diffusion has the slowest rate of 22 cm^(2)/s.The fundamental investigation on the hot electrons transport property of Au NPLs offers a new insight for designing metal-based optoelectronic devices.展开更多
The efficient transmission of severe acute respiratory syndrome-2 coronavirus(SARS-CoV-2)from patients to health care workers or family members has been a worrisome and prominent feature of the ongoing outbreak.On the...The efficient transmission of severe acute respiratory syndrome-2 coronavirus(SARS-CoV-2)from patients to health care workers or family members has been a worrisome and prominent feature of the ongoing outbreak.On the basis of clinical practice and in-vitro studies,we postulated that post-exposure prophylaxis(PEP)using Arbidol is associated with decreased infection among individuals exposed to confirmed cases of COVID-19 infection.We conducted a retrospective cohort study on family members and health care workers who were exposed to patients confirmed to have SARS-CoV-2 infection by real-time RT-PCR and chest computed tomography(CT)from January 1 to January 16,2020.The last follow-up date was Feb.26,2020.The emergence of fever and/or respiratory symptoms after exposure to the primary case was collected.The correlations between post-exposure prophylaxis and infection in household contacts and health care workers were respectively analyzed.A total of 66 members in 27 families and 124 health care workers had evidence of close exposure to patients with confirmed COVID-19.The Cox regression based on the data of the family members and health care workers with Arbidol or not showed that Arbidol PEP was a protective factor against the development of COVID-19(HR 0.025,95%CI 0.003-0.209,P=0.0006 for family members and HR 0.056,95%CI 0.005-0.662,P=0.0221 for health care workers).Our findings suggest Arbidol could reduce the infection risk of the novel coronavirus in hospital and family settings.This treatment should be promoted for PEP use and should be the subject of further investigation.展开更多
A low seed-setting rate is the main limiting factor influencing Tartary buckwheat production under high-yield cultivation conditions.To investigate the seed setting and its spatial characteristics,two Tartary buckwhea...A low seed-setting rate is the main limiting factor influencing Tartary buckwheat production under high-yield cultivation conditions.To investigate the seed setting and its spatial characteristics,two Tartary buckwheat cultivars(high seed-setting rate cultivar Qianku 3;low seed-setting rate cultivar Liuku 3)were compared by a two-year field trial in 2017 and 2018.The results showed that the Tartary buckwheat underwent simultaneous flowering and fruiting.Flowers,generated from branch,were still blooming during the mature stage of grains on stem,which resulting in a greater number of flowers and grains on the branch than those on the stem at the low part of plant.The seed-setting characteristics significantly differed between two cultivars.The high seed-setting rate of Qianku 3 was 26.6%and 33.2%higher than Liuku 3 in 2017 and 2018,respectively.Meanwhile,Qianku 3 showed a higher filled grain number(157.8%)and seed-setting rate(66.4%)on branch than Liuku 3.A network analysis showed that the whole-plant seed-setting rate was positively correlated with grain number,which was closely correlated with flower number at the same position of plant.The path-coefficient analysis revealed that grains number on branches was the most dominant component(Path coefficient(P)=2.19)of the seed-setting rate,followed by grains number on stem(P=0.60).The grains number on branches showed the greatest positive direct effect with significant correlation(r=0.76 and P<0.01)on the seed-setting rate.Overall,the present study indicated that the grain number of branches may play a vital role in improving the seed-setting rate in Tartary buckwheat.展开更多
A simple and efficient method for preparation of imines by the oxidative coupling of benzyl alcohols with aromatic amines or aliphatic amines was developed. The reaction was catalyzed by 9-azabicyclo[3.3.1]nonan-N-oxy...A simple and efficient method for preparation of imines by the oxidative coupling of benzyl alcohols with aromatic amines or aliphatic amines was developed. The reaction was catalyzed by 9-azabicyclo[3.3.1]nonan-N-oxyl（ABNO）/KOH with air as the economic and green oxidant. Under the optimal reaction conditions, a variety of imines were obtained in 80%-96% isolated yields.展开更多
基金supported by the National Natural Science Foundation of China(91545114,91545203,and 21576227)the 985 Program of the Chemistry and Chemical Engineering disciplines of Xiamen University~~
文摘Acetol is a major light oxygenate and readily produced from staged or fast pyrolysis of lignocellulose biomass. Herein we report that acetol can be selectively converted to methyl pyruvate, an important fine chemical, through oxidative esterification over Au-based catalysts. Detailed experimental studies showed that Au on amphoteric supports with appropriate strength and balanced ratio of acid and base sites can facilitate the desired oxidative-esterification pathway without accelerating undesired aldol-condensation or Cannizzaro reactions. In particular, hydroxyapatite (with a Ca/P ratio of 1.62) supported Au achieved 87% selectivity to methyl pyruvate at an acetol conversion of 62%.
基金Supported by Undergraduate Education and Teaching Reform Research Project of Chengdu University(XJJG-20242025228)Sichuan Genuine Medicinal Materials and Traditional Chinese Medicine Innovation Team(SCCXTD-2025-19)Sichuan Science and Technology Program(2021YFYZ0012).
文摘Under the background of competency-based transformation of higher education,bioengineering major urgently needs to solve the problems such as the disconnect between practical teaching and industry needs and the lack of resources.This paper proposed supplementing traditional experimental teaching with video resources to construct a closed-loop model of"theoretical instruction,case analysis,video demonstration,and reflective application".Through the development of instructional videos covering core techniques such as PCR,Western blot,CRISPR-Cas9,cell culture,HPLC,GMP operations,and bioinformatics analysis,teaching costs can be reduced,spatiotemporal constraints can be overcome,and process visualization can be enhanced,thereby supporting students in mastering the entire workflow of modern biomanufacturing.The paper further explored resource development pathways,university-enterprise collaboration mechanisms,and curriculum integration strategies,offering actionable solutions for practical teaching reform.
基金Supported by Undergraduate Education and Teaching Reform Research Project of Chengdu University(XJJG-20242025228)Sichuan Genuine Medicinal Materials and Traditional Chinese Medicine Innovation Team(SCCXTD-2025-19)Sichuan Science and Technology Program(2021YFYZ0012).
文摘The rapid advancement of the bioeconomy imposes increasingly stringent demands on bioengineering education.Drawing on data from the 2025 Chinese Undergraduate Employment Report and related sources,this study revealed that while employment placement rates for bioengineering graduates remain stable,starting salaries exhibit limited growth and career trajectories lack clarity.These challenges originate from a curriculum lagging behind technological progress,inadequate practical training,and a mismatch between student competencies and industry expectations.To address these issues,this paper proposed a strategic framework grounded in"demand-driven design,industry-education integration,and competence-centered development".Key strategies include dynamic curriculum renewal,collaborative university-industry training,holistic competency development,and personalized student support,which collectively aim at enhancing graduates employment competitiveness and long-term professional sustainability.
基金Supported by Sichuan Province Germplasm Resource Precision Identification Project(2025 Provincial Finance Agricultural High Quality Development Joint Financial Transfer Payment Fund Project)Longquanyi District Science and Technology Plan Project in 2025(2081923007)School Level Horizontal Project in 2025(2502180).
文摘Gene Engineering Principles is a fundamental professional course for majors such as bioengineering and biotechnology.It integrates theoretical knowledge with experimental practice and engineering applications.It is characterized by its comprehensive and highly practical nature.Aligning with the new-era higher education philosophy of‘competency-oriented,value-driven’teaching,this study presented a systematic exploration and practice based on undergraduate cohorts from 2018 to 2020 in Chengdu University.The reform focused on teaching methodology,formative assessment,and the integration of ideological and political education.Key strategies included the introduction of classical experimental cases,emphasis on pre-class preparation,enhancement of classroom interaction,focus on engineering-oriented applications,optimization of assessment mechanisms,and the incorporation of national strategic needs into the curriculum.These measures effectively stimulated students’learning motivation and research potential,thereby improving the overall teaching quality and educational effectiveness of the course.The results of the teaching reform demonstrate significant improvements in students’ability to apply theoretical knowledge to practical engineering problems,scientific thinking,experimental research skills,scientific reasoning,and professional identity.Reformed classes outperformed control groups across various instructional metrics,achieving notable educational outcomes.
基金financial support from the Natural Science Foundation of Xiamen City, China (3502Z20227256)National Natural Science Foundation of China (22202205, 22209170)+4 种基金XMIREM Autonomously Deployment Project, China (2023CX14, 2023GG01)Self-deployment Project Research Program of Haixi Institutes, Chinese Academy of Sciences (CXZX-2022-GH03, CXZX-2024-JQ02)Major Science and Technology Program of Xiamen City, China (3502Z20231054)National Natural Science Foundation of Fujian Province, China (2022J01502, 2024J01185)STS Program of the Chinese Academy of Sciences, China (2023T3071)。
文摘The intriguing catalytic performance of non-metallic nitrogen-doped carbon materials in the oxygen reduction reaction(ORR) has garnered considerable interest in elucidating their active site structure.The existing studies,however,present conflicting conclusions regarding the contributions of various N species to ORR activity.In this work,we designed and synthesized a series of molecules featuring well-defined structures and single N species,such as pyridinic N,graphitic N+(positively charged),and pyrrolic N,to serve as model catalysts.This approach aimed to eliminate the interference caused by the coexistence of multiple N species within carbon network,thereby providing a more precise understanding of their individual contributions to ORR activity.Our experimental results revealed that pyridinic N elevated onset potential,and graphitic N+enhanced current density in ORR.Both pyridinic N and graphitic N+can promote the transition of the ORR process from the 2e^(-) to the 4e^(-).Theoretical calculations further indicated that neutral graphitic N is more active than graphitic N+.Additionally,dynamic interconversion between graphitic N and graphitic N+(e.g.,via [4+1]e^(-),[2+1]e^(-),or [4-1]e^(-) pathways) during catalysis may adversely affect the intrinsic activity of graphitic N in practical applications.These findings provide insights into mechanism understanding in depth and design guidance for carbonbased catalysts for ORR.
基金support by the National Key R&D Program of China(Nos.2020YFA0714603 and 2020YFA0714604)。
文摘The heavy-atom effect of halogen(Br and I)has been widely employed for boosting spin-crossover in organic molecules,while recent investigation indicated halogen-substitution can also enhance fluorescence and even lead to aggregation-induced emission(AIE).In this work,we investigated ultrafast excited state dynamics of a halogen-substituted model system,i.e.squaryliums NSQ-R(R=H,Cl,Br,I),by using femtosecond spectroscopy and theoretical approach.Fast external reorganization(Ex-re,~3 ps)and slow internal reorganization(In-re,5-20 ps)were observed,while quantitative fitting indicated halogen-substitution leads to a slower non-radiative S1→S0 decay(k_(NR)^(s))and subsequently enhanced fluorescence emitting.By analyzing the extracted k_(NR)^(s)within theoretical framework of non-radiative transition in the strong coupling regime,a plausible AIE mechanism of NSQs was revealed.Our work provides a clear picture on non-radiative dynamics of halogen-substituted squaryliums,which might be useful for future development of organic dyes.
基金Supported by 2023 Major Project for Talent Cultivation and Teaching Reform in Higher Education of Sichuan Province(JG2023-77)2024-2026 Undergraduate Education and Teaching Reform Project of Chengdu University(XJJG-20242025264).
文摘Under the background of the continuous deepening of engineering education accreditation and the construction of emerging engineering disciplines,a digital platform-assisted teaching model was explored for the teaching reform of the molecular biology course to effectively support the achievement of graduation requirements for bioengineering major and enhance the teaching outcomes of the molecular biology course.The teaching reform of this course took the 2022 cohort students majoring in bioengineering in Chengdu University as the practice object.The course evaluation method was improved by integrating digital platforms for process assessment,and real-world research and practical cases were incorporated into digital platforms to enrich teaching resources.Additionally,digital platforms were integrated throughout the entire teaching process(before,during,and after class),reshaping the instructional workflow into"pre-class online self-learning,in-class teacher-student interaction for deepening knowledge internalization,and practical case studies during and after class for strengthening application".The teaching reform results demonstrated that this teaching model significantly improved the attainment of course objectives,providing valuable experience for similar institutions to advance digital course reforms under the framework of engineering education accreditation.
基金funded by Sichuan Science and Technology Program(2023YFH0006).
文摘Exploring the phenotypic trait variation and diversity of kiwifruit male plant resources can support selection,breeding,and genetic improvement,ultimately enhancing agricultural production.In this study,50 kiwifruit male plants were collected from the resource nursery of Sichuan Provincial Natural Resources Bureau.The phenotypic variation of the germplasm was analyzed using 16 quantitative traits.The analysis involved coefficient of variation(CV),Shannon-Wiener index(H),principal component analysis,correlation analysis,cluster analysis,and comprehensive evaluation.The results showed that the variation range of 16 phenotypic traits in kiwifruit male germplasm resources was 1.55%to 83.71%,with an average coefficient of variation of 28.62%,and an H index of 1.265 to 2.941.The average CVs of diploid,tetraploid,and hexaploid were 22.62%,18.99%and 18.18%,respectively,and the average CV of diploid was the largest.Indicated that the male germplasm resources of kiwifruit showed significant phenotypic diversity,and the diploid showed higher diversity characteristics.Principal component analysis(PCA)revealed that the cumulative variance contribution rate of the first seven principal components was 76.66%,which effectively captured the information from 21 traits.Cluster analysis divided the 50 kiwifruit male germplasm resources into 4 clusters;each cluster exhibited distinct phenotypic characteristics.The analysis also determined the trait characteristics and breeding value of each cluster.The results of this study provide valuable information for genetic improvement,protection,and evaluation of kiwifruit male germplasm resources.
基金supported by the National Natural Science Foundation of China(No.22273006)。
文摘The performance of cesium lead halide per-ovskite devices is seriously affected by grain boundaries and other charge traps in the poly-crystalline perovskite thin films.LiBr doping could effectively passivate defects in CsPbBr_(3) perovskite thin films,but it is still unclear that whether the passivation can help the carriers to diffuse across the grain boundaries.Here we have studied the carrier recombina-tion and diffusion dynamics in LiBr passivat-ed CsPbBr_(3) perovskite film with poly(9-vinyl-carbazole)(PVK)film underneath by using ultrafast transient absorption spectroscopy and transient absorption microscopy.The photoluminescence imaging and transient absorption morphological imaging show that LiBr passivating has made the grain size larger and reduced grain boundaries in CsPbBr_(3) film.The transient absorption spectroscopy and time-re-solved photoluminescence data indicate that LiBr passivating has slowed down the bimolecu-lar recombination rate and extended the carrier lifetime.The photoexcited hot holes in the perovskite layer would transfer to the PVK layer in the initial 2 ps.And the transient absorp-tion microscopy measurements reveal that the LiBr passivation can help the carriers to diffuse across the grain boundaries to the surrounding grains in the CsPbBr_(3) perovskite films.The carrier diffusion time is around 100 ps when the distance between two grains is~0.9μm.
基金supported by the National Natural Science Foundation of China(No.22273006).
文摘The gold nano-plates(Au NPLs)have been extensively studied for their high quality factor as mechanical resonators.But it remains still unclear how the thickness and morphology of Au NPLs affect the hot electron diffusion.Here we have employed transient absorption microscopy to gain spatiotemporal imaging of the hot electron diffusion in Au NPLs.Au NPLs of varying thickness over 200 nm were synthesized.It was found that the hot electron diffusion of Au NPL excited at the boundary is obviously faster than that excited at the internal surface.And thinner Au NPLs exhibit a faster hot electron diffusion rate compared to thicker Au NPLs.Because the time constant of hot electron cooling(electron-phonon coupling)is independent of the excited position and thickness of Au NPLs,the effect of electron-phonon coupling on hot electron diffusion should be ruled out.So the hot electron diffusion rate is highly dimensionality-dependent.The quasi-one-dimensional diffusion along the boundary of nanoplate has the fastest rate of 50 cm^(2)/s,and the three-dimensional diffusion has the slowest rate of 22 cm^(2)/s.The fundamental investigation on the hot electrons transport property of Au NPLs offers a new insight for designing metal-based optoelectronic devices.
文摘The efficient transmission of severe acute respiratory syndrome-2 coronavirus(SARS-CoV-2)from patients to health care workers or family members has been a worrisome and prominent feature of the ongoing outbreak.On the basis of clinical practice and in-vitro studies,we postulated that post-exposure prophylaxis(PEP)using Arbidol is associated with decreased infection among individuals exposed to confirmed cases of COVID-19 infection.We conducted a retrospective cohort study on family members and health care workers who were exposed to patients confirmed to have SARS-CoV-2 infection by real-time RT-PCR and chest computed tomography(CT)from January 1 to January 16,2020.The last follow-up date was Feb.26,2020.The emergence of fever and/or respiratory symptoms after exposure to the primary case was collected.The correlations between post-exposure prophylaxis and infection in household contacts and health care workers were respectively analyzed.A total of 66 members in 27 families and 124 health care workers had evidence of close exposure to patients with confirmed COVID-19.The Cox regression based on the data of the family members and health care workers with Arbidol or not showed that Arbidol PEP was a protective factor against the development of COVID-19(HR 0.025,95%CI 0.003-0.209,P=0.0006 for family members and HR 0.056,95%CI 0.005-0.662,P=0.0221 for health care workers).Our findings suggest Arbidol could reduce the infection risk of the novel coronavirus in hospital and family settings.This treatment should be promoted for PEP use and should be the subject of further investigation.
基金the National Natural Science Foundation of China(31771716)China Agriculture Research System(CARS-07-B-1)to facilitate the research.
文摘A low seed-setting rate is the main limiting factor influencing Tartary buckwheat production under high-yield cultivation conditions.To investigate the seed setting and its spatial characteristics,two Tartary buckwheat cultivars(high seed-setting rate cultivar Qianku 3;low seed-setting rate cultivar Liuku 3)were compared by a two-year field trial in 2017 and 2018.The results showed that the Tartary buckwheat underwent simultaneous flowering and fruiting.Flowers,generated from branch,were still blooming during the mature stage of grains on stem,which resulting in a greater number of flowers and grains on the branch than those on the stem at the low part of plant.The seed-setting characteristics significantly differed between two cultivars.The high seed-setting rate of Qianku 3 was 26.6%and 33.2%higher than Liuku 3 in 2017 and 2018,respectively.Meanwhile,Qianku 3 showed a higher filled grain number(157.8%)and seed-setting rate(66.4%)on branch than Liuku 3.A network analysis showed that the whole-plant seed-setting rate was positively correlated with grain number,which was closely correlated with flower number at the same position of plant.The path-coefficient analysis revealed that grains number on branches was the most dominant component(Path coefficient(P)=2.19)of the seed-setting rate,followed by grains number on stem(P=0.60).The grains number on branches showed the greatest positive direct effect with significant correlation(r=0.76 and P<0.01)on the seed-setting rate.Overall,the present study indicated that the grain number of branches may play a vital role in improving the seed-setting rate in Tartary buckwheat.
基金supported by grants No.81102194 from National Natural Science Foundation of ChinaNo.LS2010168 from Liaoning Provincial Department of Educationgrant No.00726 from China Medical Board
基金supported by the National Natural Science Foundation of China(No. 21376224)the Natural Science Foundation of Zhejiang Province(No. LY17B060007)Hangzhou Qianjiang Distinguished Experts Project
文摘A simple and efficient method for preparation of imines by the oxidative coupling of benzyl alcohols with aromatic amines or aliphatic amines was developed. The reaction was catalyzed by 9-azabicyclo[3.3.1]nonan-N-oxyl（ABNO）/KOH with air as the economic and green oxidant. Under the optimal reaction conditions, a variety of imines were obtained in 80%-96% isolated yields.
