Polymer-derived ceramic(PDC) thin films are promising wear-resistant coatings for protecting metals and carbon-carbon composites from corrosion and oxidation.However,the high pyrolysis temperature hinders the applicat...Polymer-derived ceramic(PDC) thin films are promising wear-resistant coatings for protecting metals and carbon-carbon composites from corrosion and oxidation.However,the high pyrolysis temperature hinders the applications on substrate materials with low melting points.We report a new synthesis route for PDC coatings using initiated chemical vapor deposited poly(1,3,5-trivinyl-1,3,5-trimethylcyclotrisiloxane)(pV_3D_3) as the precurs or.We investigated the changes in siloxane moieties and the network topology,and proposed a three-stage mechanism for the thermal annealing process.The rise of the connectivity number for the structures obtained at increased annealing temperatures was found with strong correlation to the enhanced mechanical properties and thermal conductivity.Our PDC films obtained via annealing at 850℃ exhibit at least 14.6% higher hardness than prior reports for PDCs synthesized below 1100℃.Furthermore,thermal conductivity up to 1.02 W(mK)^(-1) was achieved at the annealing temperature as low as 700℃,which is on the same order of magnitude as PDCs obtained above 1100℃.Using minimum thermal conductivity models,we found that the thermal transport is dominated by diffusons in the films below the percolation of rigidity,while ultra-short mean-free path phonons contribute to the thermal conductivity of the films above the percolation threshold.The findings of this work provide new insights for the development of wear-resistant and thermally conductive PDC thin films for durable protection coatings.展开更多
AIM:To figure out whether various atropine dosages may slow the progression of myopia in Chinese kids and teenagers and to determine the optimal atropine concentration for effectively slowing the progression of myopia...AIM:To figure out whether various atropine dosages may slow the progression of myopia in Chinese kids and teenagers and to determine the optimal atropine concentration for effectively slowing the progression of myopia.METHODS:A systematic search was conducted across the Cochrane Library,PubMed,Web of Science,EMBASE,CNKI,CBM,VIP,and Wanfang database,encompassing literature on slowing progression of myopia with varying atropine concentrations from database inception to January 17,2024.Data extraction and quality assessment were performed,and a network Meta-analysis was executed using Stata version 14.0 Software.Results were visually represented through graphs.RESULTS:Fourteen papers comprising 2475 cases were included;five different concentrations of atropine solution were used.The network Meta-analysis,along with the surface under the cumulative ranking curve(SUCRA),showed that 1%atropine(100%)>0.05%atropine(74.9%)>0.025%atropine(51.6%)>0.02%atropine(47.9%)>0.01%atropine(25.6%)>control in refraction change and 1%atropine(98.7%)>0.05%atropine(70.4%)>0.02%atropine(61.4%)>0.025%atropine(42%)>0.01%atropine(27.4%)>control in axial length(AL)change.CONCLUSION:In Chinese children and teenagers,the five various concentrations of atropine can reduce the progression of myopia.Although the network Meta-analysis showed that 1%atropine is the best one for controlling refraction and AL change,there is a high incidence of adverse effects with the use of 1%atropine.Therefore,we suggest that 0.05%atropine is optimal for Chinese children to slow myopia progression.展开更多
In the South China Sea, sea fog brings severe disasters every year, but forecasters have yet to implement an effective seafog forecast. To address this issue, we test a liquid-water-content-only(LWC-only) operational ...In the South China Sea, sea fog brings severe disasters every year, but forecasters have yet to implement an effective seafog forecast. To address this issue, we test a liquid-water-content-only(LWC-only) operational sea-fog prediction method based on a regional mesoscale numerical model with a horizontal resolution of about 3 km, the Global and Regional Assimilation and Prediction System(GRAPES), hereafter GRAPES-3 km. GRAPES-3 km models the LWC over the sea, from which we infer the visibility that is then used to identify fog. We test the GRAPES-3 km here against measurements in 2016 and 2017 from coastal-station observations, as well as from buoy data, data from the Integrated Observation Platform for Marine Meteorology, and retrieved fog and cloud patterns from Himawari-8 satellite data. For two cases that we examine in detail, the forecast region of sea fog overlaps well with the multi-observational data within 72 h. Considering forecasting for0–24 h, GRAPES-3 km has a 2-year-average equitable threat score(ETS) of 0.20 and a Heidke skill score(HSS) of 0.335,which is about 5.6%(ETS) and 6.4%(HSS) better than our previous method(GRAPES-MOS). Moreover, the stations near the particularly foggy region around the Leizhou Peninsula have relatively high forecast scores compared to other sea areas.Overall, the results show that GRAPES-3 km can roughly predict the formation, evolution, and dissipation of sea fog on the southern China coast.展开更多
This study analyzes the cognitive characteristics of students in communication courses in military colleges and the impact of integrated teaching of theory and practice on students’cognitive process as well as propos...This study analyzes the cognitive characteristics of students in communication courses in military colleges and the impact of integrated teaching of theory and practice on students’cognitive process as well as proposes the information processing model of students’cognitive process in the integrated teaching of theory and practice.Combining the cognitive characteristics of the students from Communication Technology,on the one hand,this study analyzes the five factors that affect the teaching effect of integrating theory and practice;on the other hand,it proposes improvement measures for the integration of theory and practice from the structure of the teaching content,teaching organization and management,modern education technology,and the ability of teachers.展开更多
Background:The extremely small amount of DNA in a cell makes it difficult to study the whole genome of single cells,so whole-genome amplification(WGA)is necessary to increase the DNA amount and enable downstream analy...Background:The extremely small amount of DNA in a cell makes it difficult to study the whole genome of single cells,so whole-genome amplification(WGA)is necessary to increase the DNA amount and enable downstream analyses.Multiple displacement amplification(MDA)is the most widely used WGA technique.Results:Compared with amplification methods based on PCR and other methods,MDA renders high-quality DNA products and better genome coverage by using phi29 DNA polymerase.Moreover,recently developed advanced MDA technologies such as microreactor MDA,emulsion MDA,and micro-channel MDA have improved amplification uniformity.Additionally,the development of other novel methods such as TruePrime WGA allows for amplification without primers.Conclusion:Here,we reviewed a selection of recently developed MDA methods,their advantages over other WGA methods,and improved MDA-based technologies,followed by a discussion of future perspectives.With the continuous development of MDA and the successive update of detection technologies,MDA will be applied in increasingly more fields and provide a solid foundation for scientific research.展开更多
Although the diploid nature has been observed for over 50 years, phasing the diploid is still a laborious task. The speed and throughput of next generation sequencing have largely increased in the past decades. Howeve...Although the diploid nature has been observed for over 50 years, phasing the diploid is still a laborious task. The speed and throughput of next generation sequencing have largely increased in the past decades. However, the short read-length remains one of the biggest challenges of haplotype analysis. For instance, reads as short as 150 bp span no more than one variant in most cases. Numerous experimental technologies have been developed to overcome this challenge. Distance, complexity and accuracy of the linkages obtained are the main factors to evaluate the efficiency of whole genome haplotyping methods. Here, we review these experimental technologies, evaluating their efficiency in linkages obtaining and system complexity. The technologies are organized into four categories based on its strategy： （i） chromosomes separation, （ii） dilution pools, （iii） crosslinking and proximity ligation, （ix） long-read technologies. Within each category, several subsections are listed to classify each technology. Innovative experimental strategies are expected to have high-quality performance, low cost and be labor-saving, which will be largely desired in the future.展开更多
基金funding from the National Natural Science Foundation of China (22178301,21938011,51876186and 52150410417)the funding from the Natural Science Foundation of Zhejiang Province (LR21B060003 and LZ19E060002)+1 种基金grant from Science Technology Department of Zhejiang Province (2023C01182)supported by Shanxi Institute of Zhejiang University for New Materials and Chemical Industry(2022SZ-TD005)。
文摘Polymer-derived ceramic(PDC) thin films are promising wear-resistant coatings for protecting metals and carbon-carbon composites from corrosion and oxidation.However,the high pyrolysis temperature hinders the applications on substrate materials with low melting points.We report a new synthesis route for PDC coatings using initiated chemical vapor deposited poly(1,3,5-trivinyl-1,3,5-trimethylcyclotrisiloxane)(pV_3D_3) as the precurs or.We investigated the changes in siloxane moieties and the network topology,and proposed a three-stage mechanism for the thermal annealing process.The rise of the connectivity number for the structures obtained at increased annealing temperatures was found with strong correlation to the enhanced mechanical properties and thermal conductivity.Our PDC films obtained via annealing at 850℃ exhibit at least 14.6% higher hardness than prior reports for PDCs synthesized below 1100℃.Furthermore,thermal conductivity up to 1.02 W(mK)^(-1) was achieved at the annealing temperature as low as 700℃,which is on the same order of magnitude as PDCs obtained above 1100℃.Using minimum thermal conductivity models,we found that the thermal transport is dominated by diffusons in the films below the percolation of rigidity,while ultra-short mean-free path phonons contribute to the thermal conductivity of the films above the percolation threshold.The findings of this work provide new insights for the development of wear-resistant and thermally conductive PDC thin films for durable protection coatings.
基金Supported by the National Key R&D Plan“Intergovernmental International Scientific and Technological Innovation Cooperation”(No.2022YFE0132600)Shenzhen Fund for Guangdong Provincial High-level Clinical Key Specialties(No.SZGSP014)+1 种基金Sanming Project of Medicine in Shenzhen(No.SZSM202311012)Shenzhen Science and Technology Program(No.KCXFZ20211020163814021).
文摘AIM:To figure out whether various atropine dosages may slow the progression of myopia in Chinese kids and teenagers and to determine the optimal atropine concentration for effectively slowing the progression of myopia.METHODS:A systematic search was conducted across the Cochrane Library,PubMed,Web of Science,EMBASE,CNKI,CBM,VIP,and Wanfang database,encompassing literature on slowing progression of myopia with varying atropine concentrations from database inception to January 17,2024.Data extraction and quality assessment were performed,and a network Meta-analysis was executed using Stata version 14.0 Software.Results were visually represented through graphs.RESULTS:Fourteen papers comprising 2475 cases were included;five different concentrations of atropine solution were used.The network Meta-analysis,along with the surface under the cumulative ranking curve(SUCRA),showed that 1%atropine(100%)>0.05%atropine(74.9%)>0.025%atropine(51.6%)>0.02%atropine(47.9%)>0.01%atropine(25.6%)>control in refraction change and 1%atropine(98.7%)>0.05%atropine(70.4%)>0.02%atropine(61.4%)>0.025%atropine(42%)>0.01%atropine(27.4%)>control in axial length(AL)change.CONCLUSION:In Chinese children and teenagers,the five various concentrations of atropine can reduce the progression of myopia.Although the network Meta-analysis showed that 1%atropine is the best one for controlling refraction and AL change,there is a high incidence of adverse effects with the use of 1%atropine.Therefore,we suggest that 0.05%atropine is optimal for Chinese children to slow myopia progression.
基金supported jointly by the National Natural Science Foundation of China (Grant Nos. 41675021, 41605006 and 41675019)the Meteorological Sciences Research Project (Grant No. GRMC2017M04)the Innovation Team of Forecasting Technology for Typhoon and Marine Meteorology of the Weather Bureau of Guangdong Province
文摘In the South China Sea, sea fog brings severe disasters every year, but forecasters have yet to implement an effective seafog forecast. To address this issue, we test a liquid-water-content-only(LWC-only) operational sea-fog prediction method based on a regional mesoscale numerical model with a horizontal resolution of about 3 km, the Global and Regional Assimilation and Prediction System(GRAPES), hereafter GRAPES-3 km. GRAPES-3 km models the LWC over the sea, from which we infer the visibility that is then used to identify fog. We test the GRAPES-3 km here against measurements in 2016 and 2017 from coastal-station observations, as well as from buoy data, data from the Integrated Observation Platform for Marine Meteorology, and retrieved fog and cloud patterns from Himawari-8 satellite data. For two cases that we examine in detail, the forecast region of sea fog overlaps well with the multi-observational data within 72 h. Considering forecasting for0–24 h, GRAPES-3 km has a 2-year-average equitable threat score(ETS) of 0.20 and a Heidke skill score(HSS) of 0.335,which is about 5.6%(ETS) and 6.4%(HSS) better than our previous method(GRAPES-MOS). Moreover, the stations near the particularly foggy region around the Leizhou Peninsula have relatively high forecast scores compared to other sea areas.Overall, the results show that GRAPES-3 km can roughly predict the formation, evolution, and dissipation of sea fog on the southern China coast.
文摘This study analyzes the cognitive characteristics of students in communication courses in military colleges and the impact of integrated teaching of theory and practice on students’cognitive process as well as proposes the information processing model of students’cognitive process in the integrated teaching of theory and practice.Combining the cognitive characteristics of the students from Communication Technology,on the one hand,this study analyzes the five factors that affect the teaching effect of integrating theory and practice;on the other hand,it proposes improvement measures for the integration of theory and practice from the structure of the teaching content,teaching organization and management,modern education technology,and the ability of teachers.
基金project 61971125 of the National Natural Science Foundation of China and the Fundamental Research Funds for the Central Universities of China.
文摘Background:The extremely small amount of DNA in a cell makes it difficult to study the whole genome of single cells,so whole-genome amplification(WGA)is necessary to increase the DNA amount and enable downstream analyses.Multiple displacement amplification(MDA)is the most widely used WGA technique.Results:Compared with amplification methods based on PCR and other methods,MDA renders high-quality DNA products and better genome coverage by using phi29 DNA polymerase.Moreover,recently developed advanced MDA technologies such as microreactor MDA,emulsion MDA,and micro-channel MDA have improved amplification uniformity.Additionally,the development of other novel methods such as TruePrime WGA allows for amplification without primers.Conclusion:Here,we reviewed a selection of recently developed MDA methods,their advantages over other WGA methods,and improved MDA-based technologies,followed by a discussion of future perspectives.With the continuous development of MDA and the successive update of detection technologies,MDA will be applied in increasingly more fields and provide a solid foundation for scientific research.
基金ACKNOWLEDGEMENTS This work was supported by the National Basic Research Program of China （No. 2012CB316501）, and the National Natural Science Foundation of China （Nos. 61227803 and 61571121）.
文摘Although the diploid nature has been observed for over 50 years, phasing the diploid is still a laborious task. The speed and throughput of next generation sequencing have largely increased in the past decades. However, the short read-length remains one of the biggest challenges of haplotype analysis. For instance, reads as short as 150 bp span no more than one variant in most cases. Numerous experimental technologies have been developed to overcome this challenge. Distance, complexity and accuracy of the linkages obtained are the main factors to evaluate the efficiency of whole genome haplotyping methods. Here, we review these experimental technologies, evaluating their efficiency in linkages obtaining and system complexity. The technologies are organized into four categories based on its strategy： （i） chromosomes separation, （ii） dilution pools, （iii） crosslinking and proximity ligation, （ix） long-read technologies. Within each category, several subsections are listed to classify each technology. Innovative experimental strategies are expected to have high-quality performance, low cost and be labor-saving, which will be largely desired in the future.
