Objective To explore the value of ECG-less technology and deep learning image reconstruction(DLIR)algorithm for coronary CT angiography(CCTA).Methods Seventy-one patients with suspected coronary artery disease(CAD)were prospectively enrolled and randomly divided into group A(n=35,underwent CCTA using ECG-less technology)and B(n=36,underwent CCTA using physical electrocardiographic gating).CCTA images of group A were reconstructed using filtered back projection(FBP),adaptive statistical iterative reconstruction V(ASiR-V)(50％blending)and high-strength DLIR(DLIR-H),respectively,while those of group B were reconstructed using conventional ASiR-V(50％blending).The radiatio n doses and examination durations of CCTA were compared between groups.Then subjective and objective evaluation of imaging quality were compared between groups and within group A among 3 reconstruction algorithms.Results No significant difference of radiation dose of CCTA was found between groups(P＞0.05).The examination duration in group A was reduced by approximately 29.37％compared to group B(P＜0.05).No significant difference of subjective image quality scores nor objective evaluation of ASiR-V reconstructed CCTA was detected between groups(all P＞0.05).In group A,compared to FBP algorithm,subjective image quality scores of DLIR-H and ASiR-V upgraded,signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)increased and standard deviation(SD)values decreased(all P＜0.05),but no significant difference of CT values was found(all P＞0.05).Conclusion ECG-less technology could significantly shorten CCTA examination duration,while DLIR could reduce image noise and improve image quality of CCTA.

Objective:To analyze the comparative results of computed tomography(CT)of inter-laboratory,and grasp the existed problems in quality control for CT examination in technical service institution of radiation health,so as to improve the ability of examination,and provide technical support for CT quality control of medical institutions.Methods:Cluster sampling method was used to extract 18 institutions with radiological health technical service,which took part in the inter-laboratory comparison for CT examination ability in Guangzhou city in December 2023.A total of 6 items,which included weighted CT dose index(CTDIw),CT value(water),noise,uniformity,high contrast resolution,and low contrast detectability,were used as the compared items.The method that single evaluation combined with comprehensive evaluation was used to analyze the submitted comparative data.The evaluation of single comparative index adopted"satisfaction","basic satisfaction"and"nonsatisfaction"to conduct evaluation,and the comprehensive evaluation used"excellent","favorable","qualified"and"unqualified"to conduct evaluation.Results:In terms of single evaluation,18 institutions with technical service participated in the comparison of 108 indicators,of which 85 items(accounting for 78.7%)were"satisfaction",and 21 items(accounting for 19.4%)were"basic satisfaction",and 2 items(accounting for 1.9%)were"nonsatisfaction".In terms of comprehensive evaluation,the result of comprehensive evaluation of 6 institutions(accounting for 33.3%)was"excellent",and that of 6 institutions(accounting for 33.3%)was"favorable",and that of 4 institutions(accounting for 22.2%)was"qualified",and that of 2 institutions(accounting for 11.1%)was"nonqualified"in the 18 technical service institutions that took part in the comparison.Conclusion:The testing capabilities and levels of various institutions with radiation health technology service for CT quality control are uneven,and there are unqualified situation in part of detection indicators.Therefore,it is necessary to pay attention to the training for the detection ability of technical personnel,and improve their detection skills to ensure the quality of technical services.

Objective To explore the value of ECG-less technology and deep learning image reconstruction(DLIR)algorithm for coronary CT angiography(CCTA).Methods Seventy-one patients with suspected coronary artery disease(CAD)were prospectively enrolled and randomly divided into group A(n=35,underwent CCTA using ECG-less technology)and B(n=36,underwent CCTA using physical electrocardiographic gating).CCTA images of group A were reconstructed using filtered back projection(FBP),adaptive statistical iterative reconstruction V(ASiR-V)(50％blending)and high-strength DLIR(DLIR-H),respectively,while those of group B were reconstructed using conventional ASiR-V(50％blending).The radiatio n doses and examination durations of CCTA were compared between groups.Then subjective and objective evaluation of imaging quality were compared between groups and within group A among 3 reconstruction algorithms.Results No significant difference of radiation dose of CCTA was found between groups(P＞0.05).The examination duration in group A was reduced by approximately 29.37％compared to group B(P＜0.05).No significant difference of subjective image quality scores nor objective evaluation of ASiR-V reconstructed CCTA was detected between groups(all P＞0.05).In group A,compared to FBP algorithm,subjective image quality scores of DLIR-H and ASiR-V upgraded,signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)increased and standard deviation(SD)values decreased(all P＜0.05),but no significant difference of CT values was found(all P＞0.05).Conclusion ECG-less technology could significantly shorten CCTA examination duration,while DLIR could reduce image noise and improve image quality of CCTA.

Objective:To analyze the comparative results of computed tomography(CT)of inter-laboratory,and grasp the existed problems in quality control for CT examination in technical service institution of radiation health,so as to improve the ability of examination,and provide technical support for CT quality control of medical institutions.Methods:Cluster sampling method was used to extract 18 institutions with radiological health technical service,which took part in the inter-laboratory comparison for CT examination ability in Guangzhou city in December 2023.A total of 6 items,which included weighted CT dose index(CTDIw),CT value(water),noise,uniformity,high contrast resolution,and low contrast detectability,were used as the compared items.The method that single evaluation combined with comprehensive evaluation was used to analyze the submitted comparative data.The evaluation of single comparative index adopted"satisfaction","basic satisfaction"and"nonsatisfaction"to conduct evaluation,and the comprehensive evaluation used"excellent","favorable","qualified"and"unqualified"to conduct evaluation.Results:In terms of single evaluation,18 institutions with technical service participated in the comparison of 108 indicators,of which 85 items(accounting for 78.7%)were"satisfaction",and 21 items(accounting for 19.4%)were"basic satisfaction",and 2 items(accounting for 1.9%)were"nonsatisfaction".In terms of comprehensive evaluation,the result of comprehensive evaluation of 6 institutions(accounting for 33.3%)was"excellent",and that of 6 institutions(accounting for 33.3%)was"favorable",and that of 4 institutions(accounting for 22.2%)was"qualified",and that of 2 institutions(accounting for 11.1%)was"nonqualified"in the 18 technical service institutions that took part in the comparison.Conclusion:The testing capabilities and levels of various institutions with radiation health technology service for CT quality control are uneven,and there are unqualified situation in part of detection indicators.Therefore,it is necessary to pay attention to the training for the detection ability of technical personnel,and improve their detection skills to ensure the quality of technical services.

Objective:To analyze and verify the distribution characteristics of radiation dose on the body surface of surgeons in cardiovascular interventional treatment,so as to provide theoretical basis for studying the characteristics of radiation dose and implementing radiation protection correctly.Methods:During cardiovascular interventional surgery,three pieces of lead protective clothing(designated as lead protective clothing A,B,and C)were provided in the room of digital subtraction angiography(DSA)equipment.Each piece of these protective clothing included one lead scarf,one lead vest and one lead apron,and the lead equivalents of them were all 0.5 mmPb.A thermoluminescence dosimeter was placed on the outer surface of the lead protective clothing that was worn by surgeon,and the radiation dose values of the front and back,vertical and horizontal surfaces of the three pieces of lead protective clothing were compared.Results:The measured average values of the front dosimeter of the three pieces of lead protective clothing were respectively(296.2±31.9)mSv,(196.3±20.2)mSv and(299.4±33.0)mSv,which were significantly higher than those of the back of the lead protective clothing,and the differences were statistically significant(Z=-5.522,-5.115,-4.817,Z=-5.522,-5.115,-4.817,P<0.05).The values of abdominal radiation doses on the vertical plane of the three pieces of lead protective clothing were the highest,which were respectively(356.7±58.2)mSv,(217.7±31.8)mSv and(387.4±46.3)mSv.The measured values of the dosimeter on the left side of the horizontal plane of the A,B of lead protective clothing were respectively(341.6±58.5)mSv and(229.1±32.4)mSv,which were all higher than that on the right side,with statistical significances(Z=5.890,9.068,P<0.05).The measured value of the left side of lead protective clothing was respectively higher than that of the middle side and the right side,and the differences were statistically significant(Z=5.846,9.766,P<0.05).Conclusion:The radiation dose of the front of the body surface of surgeon who undergo DSA intervention is significantly higher than that in the back of that,and the radiation dose of the abdomen on the vertical plane of the body is the highest,and the radiation dose of horizontal plane appears a decreasing trend from left to right.The detected dose data and distribution characteristics of radiation can provide research basis for radiation protection.

Strain-resource engineering is often considered as an important infrastructure of microbiology related research and industry. The western developed countries took the lead in establishing the classical microbial resource utilization method, and continuously improved the preservation system, species annotation technology and global sharing mechanism, which realized the expansion and reserve of biological resources since end of the 19th century. The rich and diversified germplasm resources, standard strains and production strains not only have important economic values, but also maintain the advantages of scientific research, bioeconomy (such as antimicrobial agents, vaccines, detection reagent development and standard development, etc.) and national security. Although there has been a lot of progress in related research in recent years, compared with developed countries, there is still a big gap in related fields in China. The investment and top-level design in this area lag far behind the western developed countries, and it is not commensurate with the current level of economic and social development in my country. Drawing lessons from the practice of WFCC and WDCM (World Data Center for Microorganisms, Global microbial data Center, affiliated to WFCC), for the purpose of collecting new clinical species/strains, this paper puts forward some suggestions on the identification, preservation and upload system of isolates.

Objective:To analyze the effects of noise exposure on the hearing at different frequencies in workers from the automobile manufacturing industry.Methods:A total of 4723 noise workers in a large automobile manufacturing company in Guangzhou were chosen as the research object by using judgment sampling method between April and July, 2018, and carried out 0.5, 1.0, 2.0, 3.0, 4.0 and 6.0 kHz pure tone audiometry threshold to analyze the characteristics of the status of hearing loss at different frequencies and its relationship with the noise exposure time.Results:The detection rate of hearing loss in noise-exposed workers was 29.8% (1406/4723) . Among them, the binaural hearing loss was 21.2% (999/4723) , and single unilateral hearing loss accounted for 8.6% (407/4723) . The hearing loss detection rate of right ear was higher than that of the left ear ( P<0.05) , especially in the 6.0 kHz ( P<0.001) . The detection rate of increased speech frequency hearing threshold was 1.9% (90/4723) , and the detection rate of increased high-frequency hearing threshold was 28.9% (1366/4723) . The detection rate of increased threshold in both the left and the right ear increased with the increase of frequency ( P<0.001) , the increased hearing threshold was the highest at the frequency of 6.0 kHz. The auditory threshold of left ear in 0.5 kHz were higher than that of right ear at the same frequency ( P<0.05) . The detection rate of hearing loss increased with the increase of noise exposure time ( P<0.001) , and the increased threshold of 3.0, 4.0 and 6.0 kHz from workers increased with the increase of noise exposure time ( P<0.001) . Conclusion:There is a significant increased threshold in workers exposed to noise frequency of 6.0 kHz, right ear is more easily damaged than left ear, there is a dose-response relationship for the noise exposure time and high-frequency hearing loss.

Objective:To analyze the effects of noise exposure on the hearing at different frequencies in workers from the automobile manufacturing industry.Methods:A total of 4723 noise workers in a large automobile manufacturing company in Guangzhou were chosen as the research object by using judgment sampling method between April and July, 2018, and carried out 0.5, 1.0, 2.0, 3.0, 4.0 and 6.0 kHz pure tone audiometry threshold to analyze the characteristics of the status of hearing loss at different frequencies and its relationship with the noise exposure time.Results:The detection rate of hearing loss in noise-exposed workers was 29.8% (1406/4723) . Among them, the binaural hearing loss was 21.2% (999/4723) , and single unilateral hearing loss accounted for 8.6% (407/4723) . The hearing loss detection rate of right ear was higher than that of the left ear ( P<0.05) , especially in the 6.0 kHz ( P<0.001) . The detection rate of increased speech frequency hearing threshold was 1.9% (90/4723) , and the detection rate of increased high-frequency hearing threshold was 28.9% (1366/4723) . The detection rate of increased threshold in both the left and the right ear increased with the increase of frequency ( P<0.001) , the increased hearing threshold was the highest at the frequency of 6.0 kHz. The auditory threshold of left ear in 0.5 kHz were higher than that of right ear at the same frequency ( P<0.05) . The detection rate of hearing loss increased with the increase of noise exposure time ( P<0.001) , and the increased threshold of 3.0, 4.0 and 6.0 kHz from workers increased with the increase of noise exposure time ( P<0.001) . Conclusion:There is a significant increased threshold in workers exposed to noise frequency of 6.0 kHz, right ear is more easily damaged than left ear, there is a dose-response relationship for the noise exposure time and high-frequency hearing loss.

Lycophytes and seed plants constitute the typical vascular plants. Lycophytes have been thought to have no paleo-polyploidization although the event is known to be critical for the fast expansion of seed plants. Here, genomic analyses including the homologous gene dot plot analysis detected multiple paleo-polyploidization events, with one occurring approximately 13-15 million years ago (MYA) and another about 125-142 MYA, during the evolution of the genome of Selaginella moellendorffii, a model lycophyte. In addition, comparative analysis of reconstructed ancestral genomes of lycophytes and angiosperms suggested that lycophytes were affected by more paleo-polyploidization events than seed plants. Results from the present genomic analyses indicate that paleo-polyploidization has contributed to the successful establishment of both lineages-lycophytes and seed plants-of vascular plants.
Evolution, Molecular ; Genome, Plant ; Genomics ; Phylogeny ; Polyploidy ; Selaginellaceae/genetics*

Objective:To investigate the effects of long-term ionizing radiation on peripheral blood cells of nuclear power workers.Methods:In March 2019, a total of 530 radiation exposed workers in the nuclear power industry who underwent in-service radiation occupational health examination in Guangzhou occupational disease prevention and control hospital in 2018 and with service age ≥1 year were selected as the radiation group. At the same time, 545 workers in nuclear power industry were selected as control group. According to the methods and requirements of GBZ 235-2011 ＂technical specification for occupational health monitoring of radiation workers＂ and GBZ 98-2017 ＂health requirements for radiation workers＂, the occupational health monitoring data were collected, and the change rules of peripheral blood cells in the two groups were analyzed.Results:Compared with the control group, the total number of WBC, NEUT, LYMP, Hb, MCV and MCHC in radiation group were lower than those in control group ( P<0.05) , and the difference was statistically significant ( P<0.05) . The MPV increased significantly ( P<0.05) . Compared with the control group, the abnormal rate of WBC and Hb in the radiation group was higher than that in the control group ( P<0.01) , but there was no significant difference in the abnormal rate of RBC and PLT ( P>0.05) . Conclusion:Low dose ionizing radiation has a certain cumulative damage effect on peripheral blood cells of radiation workers in nuclear power industry. The change rules of different cell subtypes are different, and the changes of WBC and PLT appear earlier.