Standard bacterial suspensions play a crucial role in microbiological diagnosis.Traditional prepar-ation methods,which rely heavily on manual operations,face challenges such as poor reproducibility,low ef-ficiency,and...Standard bacterial suspensions play a crucial role in microbiological diagnosis.Traditional prepar-ation methods,which rely heavily on manual operations,face challenges such as poor reproducibility,low ef-ficiency,and biosafety concerns.In this study,we propose a high-precision automated colony extraction and separation system that combines large-field imaging and artificial intelligence(AI)to facilitate intelligent screening and localization of colonies.Firstly,a large-field imaging system was developed to capture high-resolution images of 90 mm Petri dishes,achieving a physical resolution of 13.2μm and an imaging speed of 13 frames per second.Subsequently,AI technology was employed for the automatic recognition and localiza-tion of colonies,enabling the selection of target colonies with diameters ranging from 1.9 to 2.3 mm.Next,a three-axis motion control platform was designed,accompanied by a path planning algorithm for the efficient extraction of colonies.An electronic pipette was employed for accurate colony collection.Additionally,a bacterial suspension concentration measurement module was developed,incorporating a 650 nm laser diode as the light source,achieving a measurement accuracy of 0.01 McFarland concentration(MCF).Finally,the system’s performance was validated through the preparation of an Esckerichia coli(E.coli)suspension.After 17 hours of cultivation,E.coli was extracted four times,achieving the target concentration set by the system.This work is expected to enable rapid and accurate microbial sample preparation,significantly reducing de-tection cycles and alleviating the workload of healthcare personnel.展开更多
Objective This study aims to investigate the joint associations of sarcopenia and social isolation with mortality risk.Methods Using data from the Chinese Longitudinal Healthy Longevity Survey(CLHLS)and the UK Biobank...Objective This study aims to investigate the joint associations of sarcopenia and social isolation with mortality risk.Methods Using data from the Chinese Longitudinal Healthy Longevity Survey(CLHLS)and the UK Biobank,sarcopenia was diagnosed according to European and Asian Working Groups for Sarcopenia criteria.Social isolation was assessed using standardized questionnaires,including questions on solitude,frequency of social activities,contact with others,and marital status(for the CLHLS only).Results During the follow-up period,8,249 deaths occurred in the CLHLS and 26,670 deaths in the UK Biobank groups.While no significant interaction was observed between sarcopenia and social isolation in predicting all-cause mortality in the CLHLS cohort,the association between social isolation and mortality was stronger among individuals with sarcopenia in the UK Biobank(P-interaction=0.03,relative risk due to interaction:0.23,95%confidence interval[CI]:0.06–0.41).Further joint analyses showed that participants with sarcopenia and high levels of social isolation had the highest mortality risk(hazard ration[HR]:1.99;95%CI:[1.74–2.28]in the CLHLS and 1.69[1.55–1.85]in the UK Biobank)compared to those without either condition.Conclusion The combination of social isolation and sarcopenia synergistically increases the risk of mortality in middle-aged and older adults across diverse populations.展开更多
Isolation technology can reduce the type of structural damage that earthquakes cause.A new type of composite sliding-rolling friction composite seismic isolation bearing(SRF)with composite sliding friction and rolling...Isolation technology can reduce the type of structural damage that earthquakes cause.A new type of composite sliding-rolling friction composite seismic isolation bearing(SRF)with composite sliding friction and rolling friction is proposed.SRF is capable of realizing a parallel arrangement of sliding friction and rolling friction,and the coefficient of dynamic friction shows variability.The proposed static tests on composite bearings were conducted to investigate the effects of the number of shims,loading speed and vertical pressure on the dynamic friction factor.Test results show that the coefficient of dynamic friction first generally decreases and then increases with an increase in sliding speed,prior to again decreasing with an increase in vertical pressure.The dynamic friction factor increases and then decreases with an increase in the number of shims for a four-roll ball.It decreases and then increases with an increase in the number of shims for a five-roll ball.Based on finite element analysis,modeling and analyzing the effects of the coefficient of friction,the number of balls and the number of shims on the hysteresis performance of the support and derive its skeleton curve.The SRF hysteretic performance,dynamic friction factor and the number of rolling balls and shims show significant correlation.展开更多
Natural hybridization is known to play a vital role in speciation;however,the mechanisms underlying the early stages of natural hybridization remain unclear.Where two plant species come into contact,two driving forces...Natural hybridization is known to play a vital role in speciation;however,the mechanisms underlying the early stages of natural hybridization remain unclear.Where two plant species come into contact,two driving forces may balance the dynamic consequences of hybridization:fusion by hybridization-mediated gene flow,and separation by reproductive isolation(RI)(Ma et al.,2010a,b;Chang et al.,2022).展开更多
Hybrid-sterility-mediated reproductive isolation is pivotal for speciation,yet the underlying molecular mechanisms and environmental responses remain unclear.Here,we report a temperature-sensitive pollen killer-protec...Hybrid-sterility-mediated reproductive isolation is pivotal for speciation,yet the underlying molecular mechanisms and environmental responses remain unclear.Here,we report a temperature-sensitive pollen killer-protector system at a three-gene Sa locus for indica-japonica rice hybrid sterility.Genetic analyses identified SaFL^(+),a strong pollen protector from Sa-i(indica allele),and SaFL^(-),a weak japonica allele from Sa-j,which is exclusively functional under high temperatures.Protein interaction,ubiquitination,and degradation assays showed that SaF^(+)and SaM^(+)from Sa-i form a pollen-killer complex to bind and ubiquitinate the reactive oxygen species scavenger COX11 for degradation in mitochondria,causing male sterility of the Sa-j pollen.Protein affinity and competitive binding assays indicated that in the Sa-i pollen,SaFL^(+)binds SaM^(+)to disrupt the killer complex and restore fertility.However,the weak protector SaFL^(-)can bind SaM^(+)under high temperatures,sparing the Sa-j pollen from sterility.Synteny comparisons and haplotype analyses showed that the Sa locus originated in ancient wild rice and underwent divergence within the Oryza genus during expansion from tropical to temperate environments,which might have driven latitudinal adaptation and reproductive isolation in rice populations.Thus,Sa represents a temperature-sensitive reproductive-isolation system associated with domestication and environmental adaptation in rice.展开更多
文摘Standard bacterial suspensions play a crucial role in microbiological diagnosis.Traditional prepar-ation methods,which rely heavily on manual operations,face challenges such as poor reproducibility,low ef-ficiency,and biosafety concerns.In this study,we propose a high-precision automated colony extraction and separation system that combines large-field imaging and artificial intelligence(AI)to facilitate intelligent screening and localization of colonies.Firstly,a large-field imaging system was developed to capture high-resolution images of 90 mm Petri dishes,achieving a physical resolution of 13.2μm and an imaging speed of 13 frames per second.Subsequently,AI technology was employed for the automatic recognition and localiza-tion of colonies,enabling the selection of target colonies with diameters ranging from 1.9 to 2.3 mm.Next,a three-axis motion control platform was designed,accompanied by a path planning algorithm for the efficient extraction of colonies.An electronic pipette was employed for accurate colony collection.Additionally,a bacterial suspension concentration measurement module was developed,incorporating a 650 nm laser diode as the light source,achieving a measurement accuracy of 0.01 McFarland concentration(MCF).Finally,the system’s performance was validated through the preparation of an Esckerichia coli(E.coli)suspension.After 17 hours of cultivation,E.coli was extracted four times,achieving the target concentration set by the system.This work is expected to enable rapid and accurate microbial sample preparation,significantly reducing de-tection cycles and alleviating the workload of healthcare personnel.
基金supported by grants from the National Key Research and Development Program of China(No.2023YFC3606300,No.2022YFC3600300)the National Natural Science Foundation of China(No.82325043)the National Key Research and Development Program of Hubei Province(2022BCA036)。
文摘Objective This study aims to investigate the joint associations of sarcopenia and social isolation with mortality risk.Methods Using data from the Chinese Longitudinal Healthy Longevity Survey(CLHLS)and the UK Biobank,sarcopenia was diagnosed according to European and Asian Working Groups for Sarcopenia criteria.Social isolation was assessed using standardized questionnaires,including questions on solitude,frequency of social activities,contact with others,and marital status(for the CLHLS only).Results During the follow-up period,8,249 deaths occurred in the CLHLS and 26,670 deaths in the UK Biobank groups.While no significant interaction was observed between sarcopenia and social isolation in predicting all-cause mortality in the CLHLS cohort,the association between social isolation and mortality was stronger among individuals with sarcopenia in the UK Biobank(P-interaction=0.03,relative risk due to interaction:0.23,95%confidence interval[CI]:0.06–0.41).Further joint analyses showed that participants with sarcopenia and high levels of social isolation had the highest mortality risk(hazard ration[HR]:1.99;95%CI:[1.74–2.28]in the CLHLS and 1.69[1.55–1.85]in the UK Biobank)compared to those without either condition.Conclusion The combination of social isolation and sarcopenia synergistically increases the risk of mortality in middle-aged and older adults across diverse populations.
文摘Isolation technology can reduce the type of structural damage that earthquakes cause.A new type of composite sliding-rolling friction composite seismic isolation bearing(SRF)with composite sliding friction and rolling friction is proposed.SRF is capable of realizing a parallel arrangement of sliding friction and rolling friction,and the coefficient of dynamic friction shows variability.The proposed static tests on composite bearings were conducted to investigate the effects of the number of shims,loading speed and vertical pressure on the dynamic friction factor.Test results show that the coefficient of dynamic friction first generally decreases and then increases with an increase in sliding speed,prior to again decreasing with an increase in vertical pressure.The dynamic friction factor increases and then decreases with an increase in the number of shims for a four-roll ball.It decreases and then increases with an increase in the number of shims for a five-roll ball.Based on finite element analysis,modeling and analyzing the effects of the coefficient of friction,the number of balls and the number of shims on the hysteresis performance of the support and derive its skeleton curve.The SRF hysteretic performance,dynamic friction factor and the number of rolling balls and shims show significant correlation.
基金supported by the National Natural Science Foundation of China(U23A20160,32360336)Guizhou Provincial Key Technology R&D Program(Qian KeHe ZhiCheng[2023]YiBan035).
文摘Natural hybridization is known to play a vital role in speciation;however,the mechanisms underlying the early stages of natural hybridization remain unclear.Where two plant species come into contact,two driving forces may balance the dynamic consequences of hybridization:fusion by hybridization-mediated gene flow,and separation by reproductive isolation(RI)(Ma et al.,2010a,b;Chang et al.,2022).
基金supported by the National Natural Science Foundation of China(32030080 to L.C.and 31991222 to Y.-G.L.)the Open Competition Program of the Top Ten Critical Priorities of Agricultural Science and Technology Innovation for the 14th Five-Year Plan of Guangdong Province(2022SDZG05 to L.C.)+1 种基金the Guangdong Basic and Applied Basic Research Foundation(2022A1515110431 to G.L.and 2019B030302006 to Y.-G.L.)the Invigorate the Seed Industry of Guangdong Province(2024-NPY-00-044 to L.C.).
文摘Hybrid-sterility-mediated reproductive isolation is pivotal for speciation,yet the underlying molecular mechanisms and environmental responses remain unclear.Here,we report a temperature-sensitive pollen killer-protector system at a three-gene Sa locus for indica-japonica rice hybrid sterility.Genetic analyses identified SaFL^(+),a strong pollen protector from Sa-i(indica allele),and SaFL^(-),a weak japonica allele from Sa-j,which is exclusively functional under high temperatures.Protein interaction,ubiquitination,and degradation assays showed that SaF^(+)and SaM^(+)from Sa-i form a pollen-killer complex to bind and ubiquitinate the reactive oxygen species scavenger COX11 for degradation in mitochondria,causing male sterility of the Sa-j pollen.Protein affinity and competitive binding assays indicated that in the Sa-i pollen,SaFL^(+)binds SaM^(+)to disrupt the killer complex and restore fertility.However,the weak protector SaFL^(-)can bind SaM^(+)under high temperatures,sparing the Sa-j pollen from sterility.Synteny comparisons and haplotype analyses showed that the Sa locus originated in ancient wild rice and underwent divergence within the Oryza genus during expansion from tropical to temperate environments,which might have driven latitudinal adaptation and reproductive isolation in rice populations.Thus,Sa represents a temperature-sensitive reproductive-isolation system associated with domestication and environmental adaptation in rice.
