Detecting remote homology proteins is a challenging problem for both basic research and drug development. Although there are a couple of methods to deal with this problem, the benchmark datasets based on which the exi...Detecting remote homology proteins is a challenging problem for both basic research and drug development. Although there are a couple of methods to deal with this problem, the benchmark datasets based on which the existing methods were trained and tested contain many high homologous samples as reflected by the fact that the cutoff threshold was set at 95%. In this study, we reconstructed the benchmark dataset by setting the threshold at 40%, meaning none of the proteins included in the benchmark dataset has more than 40% pairwise sequence identity with any other in the same subset. Using the new benchmark dataset, we proposed a new predictor called “dRHP-GreyFun” based on the grey modeling and functional domain approach. Rigorous cross-validations have indicated that the new predictor is superior to its counterparts in both enhancing success rates and reducing computational cost. The predictor can be downloaded from https://github.com/jcilwz/dRHP-GreyFun.展开更多
The basic unit in life is cell.?It contains many protein molecules located at its different organelles. The growth and reproduction of a cell as well as most of its other biological functions are performed via these p...The basic unit in life is cell.?It contains many protein molecules located at its different organelles. The growth and reproduction of a cell as well as most of its other biological functions are performed via these proteins. But proteins in different organelles or subcellular locations have different functions. Facing?the avalanche of protein sequences generated in the postgenomic age, we are challenged to develop high throughput tools for identifying the subcellular localization of proteins based on their sequence information alone. Although considerable efforts have been made in this regard, the problem is far apart from being solved yet. Most existing methods can be used to deal with single-location proteins only. Actually, proteins with multi-locations may have some special biological functions that are particularly important for drug targets. Using the ML-GKR (Multi-Label Gaussian Kernel Regression) method,?we developed a new predictor called “pLoc-mGpos” by in-depth extracting the key information from GO (Gene Ontology) into the Chou’s general PseAAC (Pseudo Amino Acid Composition)?for predicting the subcellular localization of Gram-positive bacterial proteins with both single and multiple location sites. Rigorous cross-validation on a same stringent benchmark dataset indicated that the proposed pLoc-mGpos predictor is remarkably superior to “iLoc-Gpos”, the state-of-the-art predictor for the same purpose.?To maximize the convenience of most experimental scientists, a user-friendly web-server for the new powerful predictor has been established at http://www.jci-bioinfo.cn/pLoc-mGpos/, by which users can easily get their desired results without the need to go through the complicated mathematics involved.展开更多
The wenxiang diagram was proposed to represent α-helices in a 2D (two dimensional) space (Chou, K.C., Zhang, C.T., Maggiora, G.M. Proteins: Struct., Funct., Genet., 1997, 28, 99-108). It has the capacity to provide m...The wenxiang diagram was proposed to represent α-helices in a 2D (two dimensional) space (Chou, K.C., Zhang, C.T., Maggiora, G.M. Proteins: Struct., Funct., Genet., 1997, 28, 99-108). It has the capacity to provide more information in a 2D plane about each of the constituent amino acid residues in an α-helix, and is particularly useful for studying and analyzing amphiphilic helices. To meet the increasing requests for getting the program of generating wenxiang diagrams, a user-friendly web-server called “Wenxiang” has been established. It is accessible to the public at the web-site http://www.jci-bioinfo.cn/wenxiang2 or http://icpr.jci.edu.cn/bioinfo/wenxiang2. Further- more, for the convenience of users, here we provide a step-to-step guide for how to use the Wenxiang web-server to generate the desired wenxiang diagrams.展开更多
The local auxin distribution characteristics in the roots,stems,and leaves of stably transformed plantlets of trifoliate orange(Poncirus trifoliata)with auxin reporter system DR5::GUS-YFP were elucidated in this resea...The local auxin distribution characteristics in the roots,stems,and leaves of stably transformed plantlets of trifoliate orange(Poncirus trifoliata)with auxin reporter system DR5::GUS-YFP were elucidated in this research.The auxin response maxima could be observed in the apex of the root tip,primary phloem of the tender stem,and the margin of the young leaves according to the activity of theβ-glucuronidase(GUS)reporter gene triggered by the auxin responsive DR5 promoter.Auxin responses in the apex of the root tips increased when treated with synthetic auxin 1-naphthylacetic acid(NAA),but decreased when treated with the auxin polar transportation inhibitor 2,3,5-triiodobenzoic acid(TIBA).These results indicated that the DR5 reporter system worked in P.trifoliata for auxin distribution and response observation.Trifoliate orange is highly susceptible to citrus canker disease.Auxin accumulation was observed visually in the invasion sites of the detached leaves inoculated with Xanthomonas axonopodis pv.citri(Xac)by GUS staining;the upregulated expression of the YFP,GH3.1,GH3.9,and SAUR genes assessed by quantitative real-time PCR(qRT-PCR)also identified auxin accumulation in the inoculated tissues following Xac infection.Overall,these findings indicated that the plantlets of P.trifoliata engineered with the auxin reporter gene provided a promising system for studying auxin responses during Xac infection.展开更多
Objective To investigate the epidemiological features in children after the coronavirus disease 2019(COVID-19)pandemic.Methods This study collected throat swabs and serum samples from hospitalized pediatric patients o...Objective To investigate the epidemiological features in children after the coronavirus disease 2019(COVID-19)pandemic.Methods This study collected throat swabs and serum samples from hospitalized pediatric patients of Renmin Hospital of Wuhan University,Wuhan,Hubei province,China before and after the COVID-19 pandemic.Respiratory infected pathogens[adenovirus(ADV),influenza virus A/B(Flu A/B),parainfluenza virus 1/2/3(PIV1/2/3),respiratory syncytial virus(RSV),Mycoplasma pneumoniae(MP),and Chlamydia pneumoniae(CP)]were detected.The pathogens,age,and gender were used to analyze the epidemiological features in children after the COVID-19 pandemic.Results The pathogen detection rate was significantly higher in females than in males(P<0.05),and the infection of PIV1 and MP was mainly manifested.After the COVID-19 pandemic,PIV1,PIV3,RSV,and MP had statistically different detection rates among the age groups(P<0.05),and was mainly detected in patients aged 0–6 years,0–3 years,0–3 years,and 1–6 years,respectively.When comparing before the COVID-19 pandemic,the total detection rate of common respiratory pathogens was lower(P<0.05).Except for the increase in the detection rate of PIV1 and CP,the infection rate of other pathogens had almost decreased.Conclusion The prevention and control measures for the COVID-19 pandemic effectively changed the epidemiological features of common respiratory tract infectious diseases in pediatric children.展开更多
Objective:To analyze the law of acupoint selection in treatment of depression after stroke by using data mining technique,providing reference for clinical treatment.Methods:Through the retrieval of CNKI,wanfang data r...Objective:To analyze the law of acupoint selection in treatment of depression after stroke by using data mining technique,providing reference for clinical treatment.Methods:Through the retrieval of CNKI,wanfang data resource system and Vip Database,relevant literature on acupuncture treatment of this disease in China from the inception of the database to 2019 were collected.Thus the database of acupoint prescriptions was established.SPSS20.0 and SPSS Modeler 18.0 software were used for statistical analysis to explore the law of acupoint selection.Results:A total of 92 articles were selected,92 acupuncture prescriptions and 88 acupoints with a total frequency of 715 times.The frequency of acupoints of Du channel ranked first.The frequency of acupoints in the head and neck and lower limbs were successively 40.42%(289/715)and 20.46%(172/715).Specific acupoints accounted for 81.82%of the acupoints used,among which confluent acupoints ranked first.The correlation analysis results showed that the highest support of acupoint combination was Baihui(GV20)and Shenting(GV24).Conclusion:The acupoint selection in the treatment of PSD gives priority to the Du channel,following the principle of local acupoint selection,local and remote acupoint selection with the precondition of regulation the mind.Attach importance to the use of specific acupoints,especially the confluent points.展开更多
Determination of whether multidrug nanocarriers can deliver and release loaded drugs at a predefined synergistic ratio to target cancer cells is crucial.Although there are many successful applications for delivery of ...Determination of whether multidrug nanocarriers can deliver and release loaded drugs at a predefined synergistic ratio to target cancer cells is crucial.Although there are many successful applications for delivery of multiple drugs,most current carriers are unable to achieve coordinated loading and release,leading to a drug release ratio that disagrees with the predefined loading ratio.In this work,a simple dual-drug delivery system with a flexible and controllable drug release ratio was constructed to deliver two anticancer drugs,doxorubicin(DOX)and curcumin(CUR).The drug ratio of DOX and CUR can be easily tuned for an enhanced synergistic effect,and the drugs can be released at predesigned ratios due to synchronous drug activation and nanoparticle collapse.Drug release at predefined ratios for synergistic anticancer therapy was demonstrated via in vitro and in vivo experiments.展开更多
Optical bound states in the continuum (BICs) are spatially localized states with vanishing radiation, despite their energy embedded in the continuum spectrum of the environment. They are expected to greatly enhance li...Optical bound states in the continuum (BICs) are spatially localized states with vanishing radiation, despite their energy embedded in the continuum spectrum of the environment. They are expected to greatly enhance light–matter interaction due to their long lifetime and high quality factor. However, the BICs in all-dielectric structures generally exhibit large mode volumes and their properties are difficult to manipulate. In this paper, we propose a metal–dielectric hybrid nanostructure where a silver film is inserted into the silicon (Si) substrate under the Si nanopillar array. We show that symmetry-protected BIC in this system can couple with surface plasmon polaritons (SPPs) to form a hybridized mode. Compared with previous symmetry-protected BICs in all-dielectric structures, the SPP-coupled BIC has a significantly decreased mode volume, and its corresponding electric field is strongly localized below the Si nanopillars. We also show that the SPP mode makes the original polarizationindependent symmetry-protected BIC become polarization-dependent. In addition, we demonstrate that the silver film in the considered structure can induce a metal mirror effect. The destructive interference between the magnetic dipole inside the Si nanopillars and the mirror magnetic dipole in the silver film can lead to the formation of accidental BICs. Our hybrid structure provides a versatile platform for the manipulation of light–matter interaction in the nanoscale.展开更多
As trifluoromethylthiolation has received increasing attention recently, many CF_3S-reagents and trifluoromethylthiolation methods have been developed. Herein we describe trifluoromethylthiolation of alkyl halides by ...As trifluoromethylthiolation has received increasing attention recently, many CF_3S-reagents and trifluoromethylthiolation methods have been developed. Herein we describe trifluoromethylthiolation of alkyl halides by using Ph_3 P^+CF_2CO_2 as a fluoride and difluorocarbene source. Difluorocarbene is a versatile intermediate, but its side reactions are usually ignored and the by-products would therefore be discarded. In this work, a side reaction of difluorocarbene, the generation of a fluoride anion from difluorocarbene, was developed into a synthetic tool. Although the trifluoromethylthiolation reaction involved multi-sequential steps, the cleavage of C-F bond, the formation of CF_2=S bond, F-C(S)F_2 bond,and C-SCF_3 bond, the conversion proceeded fast and was completed within 10 min.展开更多
Background High-voltage analog X-ray examination is a main tool for pneumoconiosis,which is challenged by digital radiography （DR）.The tube voltage of DR chest films required for diagnosis and staging of pneumoconio...Background High-voltage analog X-ray examination is a main tool for pneumoconiosis,which is challenged by digital radiography （DR）.The tube voltage of DR chest films required for diagnosis and staging of pneumoconiosis is concerned technically.We investigated the influence of the tube voltage on chest X-ray DR image quality of patients exposed to occupational dust.Methods DR images of the CDRAD2.0model,an anatomical chest phantom,and 136 exposed workers were analyzed at different tube voltages by threereaders.Image quality factors （IQF） were calculated and compared using the CDRAD2.0 model.DR images of ten anatomic positions were scored against those of the high-kilovolt chest films in anatomical phantom and clinical cases,and differences in scores were analyzed.Results In the CDRAD2.0 model,all three readers had a minimal IQF at 120 kV （mean：22.25 kV）.The differences in the mean IQF of DR images at different tube voltages was significant （F=13.78,P〈0.001）.The IQF of DR imaging at 120 kV was similar to high kilovolt analog imaging （t=-0.58,P〉0.05）.In the anatomic phantom and clinical cases,the DR images at 120 kV were closest in anatomical detail to the high W analog images,and the means were similar （P〉0.05）.Conclusions Among different tube voltages,DR image quality is closest to the high kilovolt analog images at 120 kV in patients exposed to occupational dust.展开更多
Snake robots have great potential for exploring and operating in challenging unstructured environments,such as rubble,caves,and narrow pipelines.However,due to the complexity and unpredictability of unstructured envir...Snake robots have great potential for exploring and operating in challenging unstructured environments,such as rubble,caves,and narrow pipelines.However,due to the complexity and unpredictability of unstructured environments,designing a controller that can achieve adaptive motion is crucial.This paper proposes a self-adaptive torque-based rolling controller for snake robots,enabling compliant motion in unstructured environments.First,a controller is designed to modify the torque of each motor by focusing on the different motion states of the rolling gait.Second,an experimental platform is established for snake robots to verify the effectiveness of the controller.Finally,a series of rolling experiments are conducted using the torque-based rolling controller.In conclusion,the self-adaptive torque-based rolling controller enhances snake robot adaptability and mobility.展开更多
文摘Detecting remote homology proteins is a challenging problem for both basic research and drug development. Although there are a couple of methods to deal with this problem, the benchmark datasets based on which the existing methods were trained and tested contain many high homologous samples as reflected by the fact that the cutoff threshold was set at 95%. In this study, we reconstructed the benchmark dataset by setting the threshold at 40%, meaning none of the proteins included in the benchmark dataset has more than 40% pairwise sequence identity with any other in the same subset. Using the new benchmark dataset, we proposed a new predictor called “dRHP-GreyFun” based on the grey modeling and functional domain approach. Rigorous cross-validations have indicated that the new predictor is superior to its counterparts in both enhancing success rates and reducing computational cost. The predictor can be downloaded from https://github.com/jcilwz/dRHP-GreyFun.
文摘The basic unit in life is cell.?It contains many protein molecules located at its different organelles. The growth and reproduction of a cell as well as most of its other biological functions are performed via these proteins. But proteins in different organelles or subcellular locations have different functions. Facing?the avalanche of protein sequences generated in the postgenomic age, we are challenged to develop high throughput tools for identifying the subcellular localization of proteins based on their sequence information alone. Although considerable efforts have been made in this regard, the problem is far apart from being solved yet. Most existing methods can be used to deal with single-location proteins only. Actually, proteins with multi-locations may have some special biological functions that are particularly important for drug targets. Using the ML-GKR (Multi-Label Gaussian Kernel Regression) method,?we developed a new predictor called “pLoc-mGpos” by in-depth extracting the key information from GO (Gene Ontology) into the Chou’s general PseAAC (Pseudo Amino Acid Composition)?for predicting the subcellular localization of Gram-positive bacterial proteins with both single and multiple location sites. Rigorous cross-validation on a same stringent benchmark dataset indicated that the proposed pLoc-mGpos predictor is remarkably superior to “iLoc-Gpos”, the state-of-the-art predictor for the same purpose.?To maximize the convenience of most experimental scientists, a user-friendly web-server for the new powerful predictor has been established at http://www.jci-bioinfo.cn/pLoc-mGpos/, by which users can easily get their desired results without the need to go through the complicated mathematics involved.
文摘The wenxiang diagram was proposed to represent α-helices in a 2D (two dimensional) space (Chou, K.C., Zhang, C.T., Maggiora, G.M. Proteins: Struct., Funct., Genet., 1997, 28, 99-108). It has the capacity to provide more information in a 2D plane about each of the constituent amino acid residues in an α-helix, and is particularly useful for studying and analyzing amphiphilic helices. To meet the increasing requests for getting the program of generating wenxiang diagrams, a user-friendly web-server called “Wenxiang” has been established. It is accessible to the public at the web-site http://www.jci-bioinfo.cn/wenxiang2 or http://icpr.jci.edu.cn/bioinfo/wenxiang2. Further- more, for the convenience of users, here we provide a step-to-step guide for how to use the Wenxiang web-server to generate the desired wenxiang diagrams.
基金the National Natural Science Foundation of China(Grant No.31660564)the science and technology project of Jiangxi province(Grant Nos.20161BBF60063,151008).
文摘The local auxin distribution characteristics in the roots,stems,and leaves of stably transformed plantlets of trifoliate orange(Poncirus trifoliata)with auxin reporter system DR5::GUS-YFP were elucidated in this research.The auxin response maxima could be observed in the apex of the root tip,primary phloem of the tender stem,and the margin of the young leaves according to the activity of theβ-glucuronidase(GUS)reporter gene triggered by the auxin responsive DR5 promoter.Auxin responses in the apex of the root tips increased when treated with synthetic auxin 1-naphthylacetic acid(NAA),but decreased when treated with the auxin polar transportation inhibitor 2,3,5-triiodobenzoic acid(TIBA).These results indicated that the DR5 reporter system worked in P.trifoliata for auxin distribution and response observation.Trifoliate orange is highly susceptible to citrus canker disease.Auxin accumulation was observed visually in the invasion sites of the detached leaves inoculated with Xanthomonas axonopodis pv.citri(Xac)by GUS staining;the upregulated expression of the YFP,GH3.1,GH3.9,and SAUR genes assessed by quantitative real-time PCR(qRT-PCR)also identified auxin accumulation in the inoculated tissues following Xac infection.Overall,these findings indicated that the plantlets of P.trifoliata engineered with the auxin reporter gene provided a promising system for studying auxin responses during Xac infection.
基金supported by grants from the Fundamental Research Funds for the Central Universities(No.2042022kf1215)the Special Funds for Innovation in Scientific Research Program of Zhongshan(No.2020AG024)+4 种基金Chinese Foundation for Hepatitis Prevention and Control:TianQing Liver Disease Research Fund Subject(No.TGQB20210109)the Open Funds of Key Laboratory of Diagnosis and Treatment of Digestive System Tumors of Zhejiang Province(No.KFJJ-202005 and No.KFJJ-201907)the Open Research Program of the State Key Laboratory of Virology of China(No.2021KF002 and No.2021KF006)the Natural Science Foundation of Hubei Province(No.2020CFB619)Wuhan Municipal Health Research Foundation(No.WX21Z36).
文摘Objective To investigate the epidemiological features in children after the coronavirus disease 2019(COVID-19)pandemic.Methods This study collected throat swabs and serum samples from hospitalized pediatric patients of Renmin Hospital of Wuhan University,Wuhan,Hubei province,China before and after the COVID-19 pandemic.Respiratory infected pathogens[adenovirus(ADV),influenza virus A/B(Flu A/B),parainfluenza virus 1/2/3(PIV1/2/3),respiratory syncytial virus(RSV),Mycoplasma pneumoniae(MP),and Chlamydia pneumoniae(CP)]were detected.The pathogens,age,and gender were used to analyze the epidemiological features in children after the COVID-19 pandemic.Results The pathogen detection rate was significantly higher in females than in males(P<0.05),and the infection of PIV1 and MP was mainly manifested.After the COVID-19 pandemic,PIV1,PIV3,RSV,and MP had statistically different detection rates among the age groups(P<0.05),and was mainly detected in patients aged 0–6 years,0–3 years,0–3 years,and 1–6 years,respectively.When comparing before the COVID-19 pandemic,the total detection rate of common respiratory pathogens was lower(P<0.05).Except for the increase in the detection rate of PIV1 and CP,the infection rate of other pathogens had almost decreased.Conclusion The prevention and control measures for the COVID-19 pandemic effectively changed the epidemiological features of common respiratory tract infectious diseases in pediatric children.
文摘Objective:To analyze the law of acupoint selection in treatment of depression after stroke by using data mining technique,providing reference for clinical treatment.Methods:Through the retrieval of CNKI,wanfang data resource system and Vip Database,relevant literature on acupuncture treatment of this disease in China from the inception of the database to 2019 were collected.Thus the database of acupoint prescriptions was established.SPSS20.0 and SPSS Modeler 18.0 software were used for statistical analysis to explore the law of acupoint selection.Results:A total of 92 articles were selected,92 acupuncture prescriptions and 88 acupoints with a total frequency of 715 times.The frequency of acupoints of Du channel ranked first.The frequency of acupoints in the head and neck and lower limbs were successively 40.42%(289/715)and 20.46%(172/715).Specific acupoints accounted for 81.82%of the acupoints used,among which confluent acupoints ranked first.The correlation analysis results showed that the highest support of acupoint combination was Baihui(GV20)and Shenting(GV24).Conclusion:The acupoint selection in the treatment of PSD gives priority to the Du channel,following the principle of local acupoint selection,local and remote acupoint selection with the precondition of regulation the mind.Attach importance to the use of specific acupoints,especially the confluent points.
基金This work was supported by the National Natural Science Foundation of China(51873072,52073101)Guangdong Provincial Pearl River Talents Program(2019QN01Y088)+1 种基金the Science and Technology Program of Guangzhou(202002030268,201804020060)Outstanding Scholar Program of Bioland Laboratory(Guangzhou Regenerative Medicine and Health Guangdong Laboratory)(2018GZR110102001).
文摘Determination of whether multidrug nanocarriers can deliver and release loaded drugs at a predefined synergistic ratio to target cancer cells is crucial.Although there are many successful applications for delivery of multiple drugs,most current carriers are unable to achieve coordinated loading and release,leading to a drug release ratio that disagrees with the predefined loading ratio.In this work,a simple dual-drug delivery system with a flexible and controllable drug release ratio was constructed to deliver two anticancer drugs,doxorubicin(DOX)and curcumin(CUR).The drug ratio of DOX and CUR can be easily tuned for an enhanced synergistic effect,and the drugs can be released at predesigned ratios due to synchronous drug activation and nanoparticle collapse.Drug release at predefined ratios for synergistic anticancer therapy was demonstrated via in vitro and in vivo experiments.
基金Science and Technology Program of Guangzhou(2019050001)Natural Science Foundation of Guangdong Province (2015A030311018, 2017A030313035)Guangdong Provincial Key Laboratory (2020B1212060066)。
文摘Optical bound states in the continuum (BICs) are spatially localized states with vanishing radiation, despite their energy embedded in the continuum spectrum of the environment. They are expected to greatly enhance light–matter interaction due to their long lifetime and high quality factor. However, the BICs in all-dielectric structures generally exhibit large mode volumes and their properties are difficult to manipulate. In this paper, we propose a metal–dielectric hybrid nanostructure where a silver film is inserted into the silicon (Si) substrate under the Si nanopillar array. We show that symmetry-protected BIC in this system can couple with surface plasmon polaritons (SPPs) to form a hybridized mode. Compared with previous symmetry-protected BICs in all-dielectric structures, the SPP-coupled BIC has a significantly decreased mode volume, and its corresponding electric field is strongly localized below the Si nanopillars. We also show that the SPP mode makes the original polarizationindependent symmetry-protected BIC become polarization-dependent. In addition, we demonstrate that the silver film in the considered structure can induce a metal mirror effect. The destructive interference between the magnetic dipole inside the Si nanopillars and the mirror magnetic dipole in the silver film can lead to the formation of accidental BICs. Our hybrid structure provides a versatile platform for the manipulation of light–matter interaction in the nanoscale.
基金the National Basic Research Program of China (No. 2015CB931903)the National Natural Science Foundation of China (Nos. 21421002, 21472222, 21502214, 21672242, 81273537)+7 种基金the Chinese Academy of Sciences (Nos. XDA02020105, XDA02020106)the Key Research Program of Frontier Sciences(CAS)(No. QYZDJSSW-SLH049)the Key Project of Hunan Provincial Education Department(No. 17A190)the Zhengxiang Scholar Program of the University of South China, Hunan Provincial Hengyang City Joint Fund(No. 2017JJ4050)Hunan Graduate Science and Technology Innovation Projects (No. 2018-400)Program for Innovative Talent Team of Hengyang(No. 2017-1)the Key Project of Hengyang Science and Technology Department(No. 2017KJ166)Shanghai Research Institute of Chemical Industry Co., LTD.(No. SKL-LCTP-201802)for financial support
文摘As trifluoromethylthiolation has received increasing attention recently, many CF_3S-reagents and trifluoromethylthiolation methods have been developed. Herein we describe trifluoromethylthiolation of alkyl halides by using Ph_3 P^+CF_2CO_2 as a fluoride and difluorocarbene source. Difluorocarbene is a versatile intermediate, but its side reactions are usually ignored and the by-products would therefore be discarded. In this work, a side reaction of difluorocarbene, the generation of a fluoride anion from difluorocarbene, was developed into a synthetic tool. Although the trifluoromethylthiolation reaction involved multi-sequential steps, the cleavage of C-F bond, the formation of CF_2=S bond, F-C(S)F_2 bond,and C-SCF_3 bond, the conversion proceeded fast and was completed within 10 min.
文摘Background High-voltage analog X-ray examination is a main tool for pneumoconiosis,which is challenged by digital radiography （DR）.The tube voltage of DR chest films required for diagnosis and staging of pneumoconiosis is concerned technically.We investigated the influence of the tube voltage on chest X-ray DR image quality of patients exposed to occupational dust.Methods DR images of the CDRAD2.0model,an anatomical chest phantom,and 136 exposed workers were analyzed at different tube voltages by threereaders.Image quality factors （IQF） were calculated and compared using the CDRAD2.0 model.DR images of ten anatomic positions were scored against those of the high-kilovolt chest films in anatomical phantom and clinical cases,and differences in scores were analyzed.Results In the CDRAD2.0 model,all three readers had a minimal IQF at 120 kV （mean：22.25 kV）.The differences in the mean IQF of DR images at different tube voltages was significant （F=13.78,P〈0.001）.The IQF of DR imaging at 120 kV was similar to high kilovolt analog imaging （t=-0.58,P〉0.05）.In the anatomic phantom and clinical cases,the DR images at 120 kV were closest in anatomical detail to the high W analog images,and the means were similar （P〉0.05）.Conclusions Among different tube voltages,DR image quality is closest to the high kilovolt analog images at 120 kV in patients exposed to occupational dust.
基金supported by the National Natural Science Foundation of China(62072335)Fundamental Research Funds for the Central Universities,China(buctrc202215).
文摘Snake robots have great potential for exploring and operating in challenging unstructured environments,such as rubble,caves,and narrow pipelines.However,due to the complexity and unpredictability of unstructured environments,designing a controller that can achieve adaptive motion is crucial.This paper proposes a self-adaptive torque-based rolling controller for snake robots,enabling compliant motion in unstructured environments.First,a controller is designed to modify the torque of each motor by focusing on the different motion states of the rolling gait.Second,an experimental platform is established for snake robots to verify the effectiveness of the controller.Finally,a series of rolling experiments are conducted using the torque-based rolling controller.In conclusion,the self-adaptive torque-based rolling controller enhances snake robot adaptability and mobility.
