Manufacturing-robust imaging systems leveraging computational optics hold immense potential for easing manufacturing constraints and enabling the development of cost-effective,high-quality imaging solutions.However,co...Manufacturing-robust imaging systems leveraging computational optics hold immense potential for easing manufacturing constraints and enabling the development of cost-effective,high-quality imaging solutions.However,conventional approaches,which typically rely on data-driven neural networks to correct optical aberrations caused by manufacturing errors,are constrained by the lack of effective tolerance analysis methods for quantitatively evaluating manufacturing error boundaries.This limitation is crucial for further relaxing manufacturing constraints and providing practical guidance for fabrication.We propose a physics-informed design paradigm for manufacturing-robust imaging systems with computational optics,integrating a physics-informed tolerance analysis methodology for evaluating manufacturing error boundaries and a physics-informed neural network for image reconstruction.With this approach,we achieve a manufacturing-robust imaging system based on an off-axis three-mirror freeform all-aluminum design,delivering a modulation transfer function exceeding 0.34 at the Nyquist frequency(72 lp/mm)in simulation.Notably,this system requires a manufacturing precision of only 0.5λin root mean square(RMS),representing a remarkable 25-fold relaxation compared with the conventional requirement of 0.02λin RMS.Experimental validation further confirmed that the manufacturing-robust imaging system maintains excellent performance in diverse indoor and outdoor environments.Our proposed method paves the way for achieving high-quality imaging without the necessity of high manufacturing precision,enabling practical solutions that are more cost-effective and time-efficient.展开更多
Objective:To evaluate the safety and efficacy of neoadjuvant chemotherapy(NCT)in mid-low locally advanced rectal cancer with negative mesorectal fascia(MRF).Methods:This prospective,single-arm phaseⅡtrial was designe...Objective:To evaluate the safety and efficacy of neoadjuvant chemotherapy(NCT)in mid-low locally advanced rectal cancer with negative mesorectal fascia(MRF).Methods:This prospective,single-arm phaseⅡtrial was designed and conducted at Peking University Cancer Hospital.The patients who provided consent received 3 months of NCT(capecitabine and oxaliplatin,CapOX)followed by total mesorectal excision(TME).The primary endpoint was the rate of pathological complete response(pCR).Results:From January 2019 through December 2021,a total of 53 patients were enrolled,7.5%of whom experienced grade 3-4 adverse events during NCT.The pCR rate was 17.0%for the entire cohort,and the overall rate of postoperative complications was 37.7%(1.9%of gradeⅢa patients).The 3-year disease-free survival rate was 91.4%,and 23.5%(12/51)of the patients suffered from major low anterior resection syndrome(LARS).Postoperative complications were independently associated with major LARS.Conclusions:For patients with mid-low rectal cancer with negative MRF,3 months of NCT were found to yield a favorable tumor response with acceptable toxicity.With fair long-term survival,the NCT regimen could be associated with low rates of perioperative complications as well as acceptable anal function.展开更多
Holographic near-eye augmented reality(AR)displays featuring tilted inbound/outbound angles on compact optical combiners hold significant potential yet often struggle to deliver satisfying image quality.This is primar...Holographic near-eye augmented reality(AR)displays featuring tilted inbound/outbound angles on compact optical combiners hold significant potential yet often struggle to deliver satisfying image quality.This is primarily attributed to two reasons:the lack of a robust off-axis-supported phase hologram generation algorithm;and the suboptimal performance of ill-tuned hardware parts such as imperfect holographic optical elements(HOEs).To address these issues,we incorporate a gradient descent-based phase retrieval algorithm with spectrum remapping,allowing for precise hologram generation with wave propagation between nonparallel planes.Further,we apply a camera-calibrated propagation scheme to iteratively optimize holograms,mitigating imperfections arising from the defects in the HOE fabrication process and other hardware parts,thereby significantly lifting the holographic image quality.We build an off-axis holographic near-eye display prototype using off-the-shelf light engine parts and a customized full-color HOE,demonstrating state-of-the-art virtual reality and AR display results.展开更多
Deep space exploration equipment faces serious thermal environment problems,and radiative heat transfer is the only thermal management method,which makes developing efficient radiative thermal management technology ur...Deep space exploration equipment faces serious thermal environment problems,and radiative heat transfer is the only thermal management method,which makes developing efficient radiative thermal management technology urgent to improve the stability and safety of equipment operation in orbit.Herein,a magnetic-controlled device is proposed by dynamically flipping the Janus coating without contact for switchable solar heating and radiative cooling purposes.The Janus coating integrates an MXene solar absorber and a PDMS/Ag radiative cooler.A device is subsequently developed for experimental demonstration,which reveals that the device exhibits temperature control effects under different temperature regions(e.g.,5 K,10 K,and 20 K)and different periods(e.g.,short-term of 30 min and 12 h).In summary,this work provides a new way of thinking for the existing dynamic radiative thermal management technology based on the magnetic-controlled idea,showing considerable potential for radiative thermal management and serving for space equipment,including satellites,space stations,and spacecraft.展开更多
Purpose Colorectal cancer is a common malignant tumor worldwide.In China,the ratio of rectal cancer to coloncancer in terms of incidence is close to 1:1.Low rectal cancer accounts for more than half of all cases of re...Purpose Colorectal cancer is a common malignant tumor worldwide.In China,the ratio of rectal cancer to coloncancer in terms of incidence is close to 1:1.Low rectal cancer accounts for more than half of all cases of rectal cancer.In recent years,the proportion of rectal cancer has trended downward,however the incidence of rectal cancer inyounger adults is increasing.The CACA Guidelines for Holistic Integrative Management of Rectal Cancer were editedto help improve the diagnosis and comprehensive treatment in China.Methods This guideline has been prepared by consensuses reached by the CACA Committee of Colorectal CancerSociety,based on a careful review of the latest evidence including China’s studies,and referred to domestic and internationalrelative guidelines,also considered China’s specific national conditions and clinical practice.Results The CACA Guidelines for Holistic Integrative Management of Rectal Cancer include the epidemiology of rectalcancer,prevention and screening,diagnosis,treatment of nonmetastatic and metastatic rectal cancer,follow-up,and whole-course rehabilitation management.Conclusion Committee of Colorectal Cancer Society,Chinese Anti-Cancer Association,standardizes the diagnosisand treatment of rectal cancer in China through the formulation of the CACA Guidelines.展开更多
The conventional optical system design employs combinations of different lenses to combat aberrations, which usually leads to considerable volume and weight. In this Letter, a tailored design scheme that exploits stat...The conventional optical system design employs combinations of different lenses to combat aberrations, which usually leads to considerable volume and weight. In this Letter, a tailored design scheme that exploits state-of-the-art digital aberration correction algorithms in addition to traditional optics design is investigated. In particular, the proposed method is applied to the design of refractive telescopes by shifting the burden of correcting chromatic aberrations to software. By enforcing cross-channel information transfer in a post-processing step, the uncorrected chromatic aberrations are well-mitigated. Accordingly, a telescope of F-8, 1400 mm focal length, and 0.14° field of view is designed with only two lens elements. The image quality of the designed telescope is evaluated by comparing it to the equivalent designs with multiple lenses in a traditional optical design manner, which validates the effectiveness of our design scheme.展开更多
The rapid advancement of computer-generated holography has bridged deep learning with traditional optical principles in recent years.However,a critical challenge in this evolution is the efficient and accurate convers...The rapid advancement of computer-generated holography has bridged deep learning with traditional optical principles in recent years.However,a critical challenge in this evolution is the efficient and accurate conversion from the amplitude to phase domain for high-quality phase-only hologram(POH)generation.Existing computational models often struggle to address the inherent complexities of optical phenomena,compromising the conversion process.In this study,we present the cross-domain fusion network(CDFN),an architecture designed to tackle the complexities involved in POH generation.The CDFN employs a multi-stage(MS)mechanism to progressively learn the translation from amplitude to phase domain,complemented by the deep supervision(DS)strategy of middle features to enhance task-relevant feature learning from the initial stages.Additionally,we propose an infinite phase mapper(IPM),a phase-mapping function that circumvents the limitations of conventional activation functions and encapsulates the physical essence of holography.Through simulations,our proposed method successfully reconstructs high-quality 2K color images from the DIV2K dataset,achieving an average PSNR of 31.68 dB and SSIM of 0.944.Furthermore,we realize high-quality color image reconstruction in optical experiments.The experimental results highlight the computational intelligence and optical fidelity achieved by our proposed physics-aware cross-domain fusion.展开更多
Background. There is an increasing trend to represent domain knowledge in structured graphs, which provide efficient knowledgerepresentations for many downstream tasks. Knowledge graphs are widely used to model prior ...Background. There is an increasing trend to represent domain knowledge in structured graphs, which provide efficient knowledgerepresentations for many downstream tasks. Knowledge graphs are widely used to model prior knowledge in the form of nodesand edges to represent semantically connected knowledge entities, which several works have adopted into different medicalimaging applications. Methods. We systematically searched over five databases to find relevant articles that applied knowledgegraphs to medical imaging analysis. After screening, evaluating, and reviewing the selected articles, we performed a systematicanalysis. Results. We looked at four applications in medical imaging analysis, including disease classification, diseaselocalization and segmentation, report generation, and image retrieval. We also identified limitations of current work, such asthe limited amount of available annotated data and weak generalizability to other tasks. We further identified the potentialfuture directions according to the identified limitations, including employing semisupervised frameworks to alleviate the needfor annotated data and exploring task-agnostic models to provide better generalizability. Conclusions. We hope that our articlewill provide the readers with aggregated documentation of the state-of-the-art knowledge graph applications for medicalimaging to encourage future research.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.62192774,62105243,61925504,6201101335,62020106009,62192770,62192772,62105244,62305250,and 62322217)the Science and Technology Commission of Shanghai Municipality(Grant Nos.17JC1400800,20JC1414600,and 21JC1406100)+1 种基金the Shanghai Municipal Science and Technology Major Project(Grant No.2021SHZDZX0100)the Fundamental Research Funds for the Central Universities.
文摘Manufacturing-robust imaging systems leveraging computational optics hold immense potential for easing manufacturing constraints and enabling the development of cost-effective,high-quality imaging solutions.However,conventional approaches,which typically rely on data-driven neural networks to correct optical aberrations caused by manufacturing errors,are constrained by the lack of effective tolerance analysis methods for quantitatively evaluating manufacturing error boundaries.This limitation is crucial for further relaxing manufacturing constraints and providing practical guidance for fabrication.We propose a physics-informed design paradigm for manufacturing-robust imaging systems with computational optics,integrating a physics-informed tolerance analysis methodology for evaluating manufacturing error boundaries and a physics-informed neural network for image reconstruction.With this approach,we achieve a manufacturing-robust imaging system based on an off-axis three-mirror freeform all-aluminum design,delivering a modulation transfer function exceeding 0.34 at the Nyquist frequency(72 lp/mm)in simulation.Notably,this system requires a manufacturing precision of only 0.5λin root mean square(RMS),representing a remarkable 25-fold relaxation compared with the conventional requirement of 0.02λin RMS.Experimental validation further confirmed that the manufacturing-robust imaging system maintains excellent performance in diverse indoor and outdoor environments.Our proposed method paves the way for achieving high-quality imaging without the necessity of high manufacturing precision,enabling practical solutions that are more cost-effective and time-efficient.
基金supported by Beijing Municipal Administration of Hospitals Incubating Program (No.PZ2020027)Beijing Talent Incubating Funding (No.2019-4)+3 种基金National Natural Science Foundation of China (No.81773214)Beijing Hospitals Authority Clinical Medicine Development of Special Funding Support (No.ZYLX202116)2019 Major and Difficult Diseases Chinese and Western Medicine Coordination Capacity Colorectal Cancer Project [No.(2018)275]Science Foundation of Peking University Cancer Hospital-2023 (No.JC202310)
文摘Objective:To evaluate the safety and efficacy of neoadjuvant chemotherapy(NCT)in mid-low locally advanced rectal cancer with negative mesorectal fascia(MRF).Methods:This prospective,single-arm phaseⅡtrial was designed and conducted at Peking University Cancer Hospital.The patients who provided consent received 3 months of NCT(capecitabine and oxaliplatin,CapOX)followed by total mesorectal excision(TME).The primary endpoint was the rate of pathological complete response(pCR).Results:From January 2019 through December 2021,a total of 53 patients were enrolled,7.5%of whom experienced grade 3-4 adverse events during NCT.The pCR rate was 17.0%for the entire cohort,and the overall rate of postoperative complications was 37.7%(1.9%of gradeⅢa patients).The 3-year disease-free survival rate was 91.4%,and 23.5%(12/51)of the patients suffered from major low anterior resection syndrome(LARS).Postoperative complications were independently associated with major LARS.Conclusions:For patients with mid-low rectal cancer with negative MRF,3 months of NCT were found to yield a favorable tumor response with acceptable toxicity.With fair long-term survival,the NCT regimen could be associated with low rates of perioperative complications as well as acceptable anal function.
基金National Key Research and Development Program of China(2021YFB2802200)National Natural Science Foundation of China(62322217,62005154)+1 种基金Natural Science Foundation of Shanghai Municipality(20ZR1420500)University Grants Committee(ECS27212822,GRF 17208023)。
文摘Holographic near-eye augmented reality(AR)displays featuring tilted inbound/outbound angles on compact optical combiners hold significant potential yet often struggle to deliver satisfying image quality.This is primarily attributed to two reasons:the lack of a robust off-axis-supported phase hologram generation algorithm;and the suboptimal performance of ill-tuned hardware parts such as imperfect holographic optical elements(HOEs).To address these issues,we incorporate a gradient descent-based phase retrieval algorithm with spectrum remapping,allowing for precise hologram generation with wave propagation between nonparallel planes.Further,we apply a camera-calibrated propagation scheme to iteratively optimize holograms,mitigating imperfections arising from the defects in the HOE fabrication process and other hardware parts,thereby significantly lifting the holographic image quality.We build an off-axis holographic near-eye display prototype using off-the-shelf light engine parts and a customized full-color HOE,demonstrating state-of-the-art virtual reality and AR display results.
基金supported by the National Natural Science Foundation of China(No.52476225,No.52130601)the Young Elite Scientists Sponsorship Program by CAST(2023QNRC001)the University of Science and Technology of China-Southwest University of Science and Technology Counterpart Cooperation and Development Joint Fund(KY2090002002).
文摘Deep space exploration equipment faces serious thermal environment problems,and radiative heat transfer is the only thermal management method,which makes developing efficient radiative thermal management technology urgent to improve the stability and safety of equipment operation in orbit.Herein,a magnetic-controlled device is proposed by dynamically flipping the Janus coating without contact for switchable solar heating and radiative cooling purposes.The Janus coating integrates an MXene solar absorber and a PDMS/Ag radiative cooler.A device is subsequently developed for experimental demonstration,which reveals that the device exhibits temperature control effects under different temperature regions(e.g.,5 K,10 K,and 20 K)and different periods(e.g.,short-term of 30 min and 12 h).In summary,this work provides a new way of thinking for the existing dynamic radiative thermal management technology based on the magnetic-controlled idea,showing considerable potential for radiative thermal management and serving for space equipment,including satellites,space stations,and spacecraft.
文摘Purpose Colorectal cancer is a common malignant tumor worldwide.In China,the ratio of rectal cancer to coloncancer in terms of incidence is close to 1:1.Low rectal cancer accounts for more than half of all cases of rectal cancer.In recent years,the proportion of rectal cancer has trended downward,however the incidence of rectal cancer inyounger adults is increasing.The CACA Guidelines for Holistic Integrative Management of Rectal Cancer were editedto help improve the diagnosis and comprehensive treatment in China.Methods This guideline has been prepared by consensuses reached by the CACA Committee of Colorectal CancerSociety,based on a careful review of the latest evidence including China’s studies,and referred to domestic and internationalrelative guidelines,also considered China’s specific national conditions and clinical practice.Results The CACA Guidelines for Holistic Integrative Management of Rectal Cancer include the epidemiology of rectalcancer,prevention and screening,diagnosis,treatment of nonmetastatic and metastatic rectal cancer,follow-up,and whole-course rehabilitation management.Conclusion Committee of Colorectal Cancer Society,Chinese Anti-Cancer Association,standardizes the diagnosisand treatment of rectal cancer in China through the formulation of the CACA Guidelines.
基金supported by the Joint Foundation Program of the Chinese Academy of Sciences for Equipment Pre-Feasibility Study(No.6141A01011601)the National Natural Science Foundation of China(Nos.61775219 and61640422)the Equipment Research Program of the Chinese Academy of Sciences(No.Y70X25A1HY)
文摘The conventional optical system design employs combinations of different lenses to combat aberrations, which usually leads to considerable volume and weight. In this Letter, a tailored design scheme that exploits state-of-the-art digital aberration correction algorithms in addition to traditional optics design is investigated. In particular, the proposed method is applied to the design of refractive telescopes by shifting the burden of correcting chromatic aberrations to software. By enforcing cross-channel information transfer in a post-processing step, the uncorrected chromatic aberrations are well-mitigated. Accordingly, a telescope of F-8, 1400 mm focal length, and 0.14° field of view is designed with only two lens elements. The image quality of the designed telescope is evaluated by comparing it to the equivalent designs with multiple lenses in a traditional optical design manner, which validates the effectiveness of our design scheme.
基金National Natural Science Foundation of China(62305184)Basic and Applied Basic Research Foundation of Guangdong Province(2023A1515012932)+4 种基金Science,Technology and Innovation Commission of Shenzhen Municipality(WDZC20220818100259004)Research Grants Council of the Hong Kong Special Administrative Region,China(C5031-22G,CityU11300123,CityU11310522)Guangdong Provincial Department of Science and Technology(2020B1515120073)City University of Hong Kong(9610628)Research Grants Council of Hong Kong(ECS 27212822).
文摘The rapid advancement of computer-generated holography has bridged deep learning with traditional optical principles in recent years.However,a critical challenge in this evolution is the efficient and accurate conversion from the amplitude to phase domain for high-quality phase-only hologram(POH)generation.Existing computational models often struggle to address the inherent complexities of optical phenomena,compromising the conversion process.In this study,we present the cross-domain fusion network(CDFN),an architecture designed to tackle the complexities involved in POH generation.The CDFN employs a multi-stage(MS)mechanism to progressively learn the translation from amplitude to phase domain,complemented by the deep supervision(DS)strategy of middle features to enhance task-relevant feature learning from the initial stages.Additionally,we propose an infinite phase mapper(IPM),a phase-mapping function that circumvents the limitations of conventional activation functions and encapsulates the physical essence of holography.Through simulations,our proposed method successfully reconstructs high-quality 2K color images from the DIV2K dataset,achieving an average PSNR of 31.68 dB and SSIM of 0.944.Furthermore,we realize high-quality color image reconstruction in optical experiments.The experimental results highlight the computational intelligence and optical fidelity achieved by our proposed physics-aware cross-domain fusion.
基金the National Library of Medicine under Award No.4R00LM013001 and was also supported by Amazon Machine Learning Research Award 2020.
文摘Background. There is an increasing trend to represent domain knowledge in structured graphs, which provide efficient knowledgerepresentations for many downstream tasks. Knowledge graphs are widely used to model prior knowledge in the form of nodesand edges to represent semantically connected knowledge entities, which several works have adopted into different medicalimaging applications. Methods. We systematically searched over five databases to find relevant articles that applied knowledgegraphs to medical imaging analysis. After screening, evaluating, and reviewing the selected articles, we performed a systematicanalysis. Results. We looked at four applications in medical imaging analysis, including disease classification, diseaselocalization and segmentation, report generation, and image retrieval. We also identified limitations of current work, such asthe limited amount of available annotated data and weak generalizability to other tasks. We further identified the potentialfuture directions according to the identified limitations, including employing semisupervised frameworks to alleviate the needfor annotated data and exploring task-agnostic models to provide better generalizability. Conclusions. We hope that our articlewill provide the readers with aggregated documentation of the state-of-the-art knowledge graph applications for medicalimaging to encourage future research.
