Male muskrats(Ondatra zibethicus L.)secrete musk from their scent glands during musk secretion season.Musk plays an important role as a communication pheromone during the breeding season.In this study,gas chromatogra...Male muskrats(Ondatra zibethicus L.)secrete musk from their scent glands during musk secretion season.Musk plays an important role as a communication pheromone during the breeding season.In this study,gas chromatography–mass spectrometry(GC–MS)was used to analyze the main components of musk.The GC–MS results after methyl esterification showed that 71.55%of the musk is composed of fatty acids.The other components of muskrat musk include cholesterol(9.31%)and other organics.Transcriptome comparison between musk secretion and non-secretion seasons showed significant changes in the scent glands for 53 genes involved in fatty acid and cholesterol synthesis and metabolism regulatory pathways,which include fatty acid biosynthesis,elongation,and metabolism;steroid biosynthesis;steroid hormone biosynthesis pathways.A reverse transcription–polymerase chain reaction analysis confirmed these detected changes.Overall,our results indicated that lipid synthesis and metabolism play important roles in musk compound synthesis by providing energy for musk production,and the produced musk provides a mechanism for male muskrats to communicate with females during the breeding season.展开更多
The importance to industry of non-contact bearings is growing rapidly as the demand for highspeed and high-precision manufacturing equipment increases.As a recently developed non-contact technology,near-field acoustic...The importance to industry of non-contact bearings is growing rapidly as the demand for highspeed and high-precision manufacturing equipment increases.As a recently developed non-contact technology,near-field acoustic levitation(NFAL)has drawn much attention for the advantages it offers,including no requirement for an external pressurized air supply,its compact structure,and its ability to adapt to its environment.In this paper,the working mechanism of NFAL is introduced in detail and compared to all existing non-contact technologies to demonstrate its versatility and potential for practical applications in industry.The fundamental theory of NFAL,including gas film lubrication theory and acoustic radiation pressure theory is presented.Then,the current stateof-the-art of the design and development of squeeze film air bearings based on NFAL is reviewed.Finally,future trends and obstacles to more widespread use are discussed.展开更多
The slow axial scanning rate in multiphoton microscopy(MPM)has traditionally limited the speed of three-dimensional(3D)imaging.Recently,a lot of techniques have been proposed to speed up the axial scan;however,there i...The slow axial scanning rate in multiphoton microscopy(MPM)has traditionally limited the speed of three-dimensional(3D)imaging.Recently,a lot of techniques have been proposed to speed up the axial scan;however,there inherently exists an upper limit of the achievable maximum scanning rate restricted by full sampling.To overcome this limitation,we developed an approach to realize multiplane compressive imaging in MPM that empowers conventional laser scanning microscopies with rapid axial scanning capacity in a sub-sampling way.To realize the technique,we achieved two technical breakthroughs:first,we proposed a concept to axially encode the beam with binary intensities;second,compressive sensing theory was introduced to the axial direction in MPM based on the axial-coded point spread function.This 3D imaging technology is termed arbitrary illumination microscopy with encoded depth(AIMED),enabling a nearly double volumetric imaging speed with subcellular resolution for mouse brain neurons in experiments and performing approximately eight times faster in simulation.The axial compressive ability of AIMED can be readily extended to other microscopic modalities for achieving axially compressive 3D imaging.Our concepts demonstrated provide insights into the entire field of advanced volumetric microscopy.展开更多
Background: Exercise, as the cornerstone of pulmonary rehabilitation, is recommended to chronic obstructive pulmonary disease (COPD) patients. The underlying molecular basis and metabolic process were not fully elucid...Background: Exercise, as the cornerstone of pulmonary rehabilitation, is recommended to chronic obstructive pulmonary disease (COPD) patients. The underlying molecular basis and metabolic process were not fully elucidated. Methods: Sprague-Dawley rats were classified into five groups: non-COPD/rest ( n = 8), non-COPD/exercise ( n = 7), COPD/rest ( n = 7), COPD/medium exercise ( n = 10), and COPD/intensive exercise ( n = 10). COPD animals were exposed to cigarette smoke and lipopolysaccharide instillation for 90 days, while the non-COPD control animals were exposed to room air. Non-COPD/exercise and COPD/medium exercise animals were trained on a treadmill at a decline of 5° and a speed of 15 m/min while animals in the COPD/intensive exercise group were trained at a decline of 5° and a speed of 18 m/min. After eight weeks of exercise/rest, we used ultrasonography, immunohistochemistry, transmission electron microscopy, oxidative capacity of mitochondria, airflow-assisted desorption electrospray ionization-mass spectrometry imaging (AFADESI-MSI), and transcriptomics analyses to assess rectal femoris (RF). Results: At the end of 90 days, COPD rats’ weight gain was smaller than control by 59.48 ± 15.33 g ( P = 0.0005). The oxidative muscle fibers proportion was lower ( P < 0.0001). At the end of additional eight weeks of exercise/rest, compared to COPD/rest, COPD/medium exercise group showed advantages in weight gain, femoral artery peak flow velocity (Δ58.22 mm/s, 95% CI: 13.85-102.60 mm/s, P = 0.0104), RF diameters (Δ0.16 mm, 95% CI: 0.04-0.28 mm, P = 0.0093), myofibrils diameter (Δ0.06 μm, 95% CI: 0.02-0.10 μm, P = 0.006), oxidative muscle fiber percentage (Δ4.84%, 95% CI: 0.15-9.53%, P = 0.0434), mitochondria oxidative phosphorylate capacity ( P < 0.0001). Biomolecules spatial distribution in situ and bioinformatic analyses of transcriptomics suggested COPD-related alteration in metabolites and gene expression, which can be impacted by exercise. Conclusion: COPD rat model had multi-level structure and function impairment, which can be mitigated by exercise.展开更多
The surge in interest regarding the next generation of optical fiber transmission has stimulated the development of digital signal processing(DSP)schemes that are highly cost-effective with both high performance and l...The surge in interest regarding the next generation of optical fiber transmission has stimulated the development of digital signal processing(DSP)schemes that are highly cost-effective with both high performance and low complexity.As benchmarks for nonlinear compensation methods,however,traditional DSP designed with block-by-block modules for linear compensations,could exhibit residual linear effects after compensation,limiting the nonlinear compensation performance.Here we propose a high-efficient design thought for DSP based on the learnable perspectivity,called learnable DSP(LDSP).LDSP reuses the traditional DSP modules,regarding the whole DSP as a deep learning framework and optimizing the DSP parameters adaptively based on backpropagation algorithm from a global scale.This method not only establishes new standards in linear DSP performance but also serves as a critical benchmark for nonlinear DSP designs.In comparison to traditional DSP with hyperparameter optimization,a notable enhancement of approximately 1.21 dB in the Q factor for 400 Gb/s signal after 1600 km fiber transmission is experimentally demonstrated by combining LDSP and perturbation-based nonlinear compensation algorithm.Benefiting from the learnable model,LDSP can learn the best configuration adaptively with low complexity,reducing dependence on initial parameters.The proposed approach implements a symbol-rate DSP with a small bit error rate(BER)cost in exchange for a 48%complexity reduction compared to the conventional 2 samples/symbol processing.We believe that LDSP represents a new and highly efficient paradigm for DSP design,which is poised to attract considerable attention across various domains of optical communications.展开更多
Analysis of the intestinal microbiota and physiological parameters in mammalian infancy can reveal health status.In this study,we used a combination of molecular and immunochemical approaches to assess fecal microbiot...Analysis of the intestinal microbiota and physiological parameters in mammalian infancy can reveal health status.In this study,we used a combination of molecular and immunochemical approaches to assess fecal microbiota as well as Cortisol(Cor),Triiodothyronine(T3),and immunoglobulin A(IgA)levels of young forest musk deer(FMD),from birth to one month after weaning(7 days of age–110 days of age).During development as the diet of FMD changes from consuming milk to eating plants,the richness and diversity of intestinal microbiota of young FMD increased significantly.Cor levels remained unchanged throughout early development while significantly increased after weaning,T3 and IgA initially were derived from milk during lactation,significantly decreased after weaning.Correlation network analysis showed that the community of food-oriented microbes were highly structured and that many genera were correlated.Overall,this study provides scientific insights into effective management strategies for the protection of FMD population.展开更多
In this paper,the images of tunnel surface are obtained by tunnel lining rapid inspection system,and tunnel crack forest dataset(TCFD)is established.The disaster characteristics of tunnel cracks are analyzed and summa...In this paper,the images of tunnel surface are obtained by tunnel lining rapid inspection system,and tunnel crack forest dataset(TCFD)is established.The disaster characteristics of tunnel cracks are analyzed and summarized.Solutions of tunnel crack segmentation(TCS)method are developed for the detection and recognition of cracks on tunnel lining.According to the image features of the tunnel lining and the optical principal of detection equipment,effective image pre-processing steps are carried out before crack extraction.The tunnel image of TCFD is divided into appropriate number of blocks to magnify the local features of tunnel cracks.Local threshold segmentation method is used to traverse the blocks successively,and the first target block with crack is obtained.The seed in the target block were obtained by adaptive localization method and mapped to the whole image.Region growing is performed through crack seed until complete tunnel crack is extracted.The results show that the precision,recall rate and F-measure of tunnel cracks under the TCS method can reach 92.58%,93.07%and 92.82%without strong interference.According to the binary images processed by TCS method,the projection images of different types of tunnel cracks and their respective laws are obtained.Furthermore,the TCS method is implemented and deployed as a GUI software application.展开更多
基金This work was supported by Beijing Municipal Natural Science Foundation(Grant No.5202016)Fundamental research funds for the central universities(Grant No.2019YC18).
文摘Male muskrats(Ondatra zibethicus L.)secrete musk from their scent glands during musk secretion season.Musk plays an important role as a communication pheromone during the breeding season.In this study,gas chromatography–mass spectrometry(GC–MS)was used to analyze the main components of musk.The GC–MS results after methyl esterification showed that 71.55%of the musk is composed of fatty acids.The other components of muskrat musk include cholesterol(9.31%)and other organics.Transcriptome comparison between musk secretion and non-secretion seasons showed significant changes in the scent glands for 53 genes involved in fatty acid and cholesterol synthesis and metabolism regulatory pathways,which include fatty acid biosynthesis,elongation,and metabolism;steroid biosynthesis;steroid hormone biosynthesis pathways.A reverse transcription–polymerase chain reaction analysis confirmed these detected changes.Overall,our results indicated that lipid synthesis and metabolism play important roles in musk compound synthesis by providing energy for musk production,and the produced musk provides a mechanism for male muskrats to communicate with females during the breeding season.
基金the financial support from the National Natural Science Foundation of China(Nos.51575170 and 51875185)the National Key R&D Program of China(2018YFB2000100)the Foundation of Hunan Province(2018JJ1006).
文摘The importance to industry of non-contact bearings is growing rapidly as the demand for highspeed and high-precision manufacturing equipment increases.As a recently developed non-contact technology,near-field acoustic levitation(NFAL)has drawn much attention for the advantages it offers,including no requirement for an external pressurized air supply,its compact structure,and its ability to adapt to its environment.In this paper,the working mechanism of NFAL is introduced in detail and compared to all existing non-contact technologies to demonstrate its versatility and potential for practical applications in industry.The fundamental theory of NFAL,including gas film lubrication theory and acoustic radiation pressure theory is presented.Then,the current stateof-the-art of the design and development of squeeze film air bearings based on NFAL is reviewed.Finally,future trends and obstacles to more widespread use are discussed.
基金supported by the Research Grants Council of the Hong Kong Special Administrative Region of China(Grant Nos.HKU 17210522,HKU C7074-21G,HKU R7003-21,HKU 17205321,and HKU 17200219)the Innovation and Technology Commission of the Hong Kong SAR Government(Grant Nos.MHP/073/20,MHP/057/21,and Health@Inno HK program)+2 种基金the National Natural Science Foundation of China(Grant No.62305274)the Natural Science Foundation of Xiamen City,China(Grant No.3502Z202371001)the Fujian Provincial Natural Science Foundation(Grant No.2024J01056)。
文摘The slow axial scanning rate in multiphoton microscopy(MPM)has traditionally limited the speed of three-dimensional(3D)imaging.Recently,a lot of techniques have been proposed to speed up the axial scan;however,there inherently exists an upper limit of the achievable maximum scanning rate restricted by full sampling.To overcome this limitation,we developed an approach to realize multiplane compressive imaging in MPM that empowers conventional laser scanning microscopies with rapid axial scanning capacity in a sub-sampling way.To realize the technique,we achieved two technical breakthroughs:first,we proposed a concept to axially encode the beam with binary intensities;second,compressive sensing theory was introduced to the axial direction in MPM based on the axial-coded point spread function.This 3D imaging technology is termed arbitrary illumination microscopy with encoded depth(AIMED),enabling a nearly double volumetric imaging speed with subcellular resolution for mouse brain neurons in experiments and performing approximately eight times faster in simulation.The axial compressive ability of AIMED can be readily extended to other microscopic modalities for achieving axially compressive 3D imaging.Our concepts demonstrated provide insights into the entire field of advanced volumetric microscopy.
基金supported by grants from Chinese Academy of Medical Sciences,Innovation Fund for Medical Sciences(CIFMS)(No.2021-I2M-1-049)and(2)China-Japan Friendship Hospital Foundation for Young Scholars(No.2018-1-QN-11).
文摘Background: Exercise, as the cornerstone of pulmonary rehabilitation, is recommended to chronic obstructive pulmonary disease (COPD) patients. The underlying molecular basis and metabolic process were not fully elucidated. Methods: Sprague-Dawley rats were classified into five groups: non-COPD/rest ( n = 8), non-COPD/exercise ( n = 7), COPD/rest ( n = 7), COPD/medium exercise ( n = 10), and COPD/intensive exercise ( n = 10). COPD animals were exposed to cigarette smoke and lipopolysaccharide instillation for 90 days, while the non-COPD control animals were exposed to room air. Non-COPD/exercise and COPD/medium exercise animals were trained on a treadmill at a decline of 5° and a speed of 15 m/min while animals in the COPD/intensive exercise group were trained at a decline of 5° and a speed of 18 m/min. After eight weeks of exercise/rest, we used ultrasonography, immunohistochemistry, transmission electron microscopy, oxidative capacity of mitochondria, airflow-assisted desorption electrospray ionization-mass spectrometry imaging (AFADESI-MSI), and transcriptomics analyses to assess rectal femoris (RF). Results: At the end of 90 days, COPD rats’ weight gain was smaller than control by 59.48 ± 15.33 g ( P = 0.0005). The oxidative muscle fibers proportion was lower ( P < 0.0001). At the end of additional eight weeks of exercise/rest, compared to COPD/rest, COPD/medium exercise group showed advantages in weight gain, femoral artery peak flow velocity (Δ58.22 mm/s, 95% CI: 13.85-102.60 mm/s, P = 0.0104), RF diameters (Δ0.16 mm, 95% CI: 0.04-0.28 mm, P = 0.0093), myofibrils diameter (Δ0.06 μm, 95% CI: 0.02-0.10 μm, P = 0.006), oxidative muscle fiber percentage (Δ4.84%, 95% CI: 0.15-9.53%, P = 0.0434), mitochondria oxidative phosphorylate capacity ( P < 0.0001). Biomolecules spatial distribution in situ and bioinformatic analyses of transcriptomics suggested COPD-related alteration in metabolites and gene expression, which can be impacted by exercise. Conclusion: COPD rat model had multi-level structure and function impairment, which can be mitigated by exercise.
基金the funding provided by National Key Research and Development Program of China(2023YFB2905400)National Natural Science Foundation of China(62025503)Shanghai Jiao Tong University 2030 Initiative.
文摘The surge in interest regarding the next generation of optical fiber transmission has stimulated the development of digital signal processing(DSP)schemes that are highly cost-effective with both high performance and low complexity.As benchmarks for nonlinear compensation methods,however,traditional DSP designed with block-by-block modules for linear compensations,could exhibit residual linear effects after compensation,limiting the nonlinear compensation performance.Here we propose a high-efficient design thought for DSP based on the learnable perspectivity,called learnable DSP(LDSP).LDSP reuses the traditional DSP modules,regarding the whole DSP as a deep learning framework and optimizing the DSP parameters adaptively based on backpropagation algorithm from a global scale.This method not only establishes new standards in linear DSP performance but also serves as a critical benchmark for nonlinear DSP designs.In comparison to traditional DSP with hyperparameter optimization,a notable enhancement of approximately 1.21 dB in the Q factor for 400 Gb/s signal after 1600 km fiber transmission is experimentally demonstrated by combining LDSP and perturbation-based nonlinear compensation algorithm.Benefiting from the learnable model,LDSP can learn the best configuration adaptively with low complexity,reducing dependence on initial parameters.The proposed approach implements a symbol-rate DSP with a small bit error rate(BER)cost in exchange for a 48%complexity reduction compared to the conventional 2 samples/symbol processing.We believe that LDSP represents a new and highly efficient paradigm for DSP design,which is poised to attract considerable attention across various domains of optical communications.
基金This work was supported by the National Key R&D program of China(2018YFD0502204)the National Natural Science Foundation of China(31872962).
文摘Analysis of the intestinal microbiota and physiological parameters in mammalian infancy can reveal health status.In this study,we used a combination of molecular and immunochemical approaches to assess fecal microbiota as well as Cortisol(Cor),Triiodothyronine(T3),and immunoglobulin A(IgA)levels of young forest musk deer(FMD),from birth to one month after weaning(7 days of age–110 days of age).During development as the diet of FMD changes from consuming milk to eating plants,the richness and diversity of intestinal microbiota of young FMD increased significantly.Cor levels remained unchanged throughout early development while significantly increased after weaning,T3 and IgA initially were derived from milk during lactation,significantly decreased after weaning.Correlation network analysis showed that the community of food-oriented microbes were highly structured and that many genera were correlated.Overall,this study provides scientific insights into effective management strategies for the protection of FMD population.
基金This research is supported by the Fundamental Research Funds for the Central Universities,China(300102120301)Natural Science Basic Research Plan in Shaanxi Province of China(2021JQ-216)Scientific Innovation Practice Project of Postgraduates of Chang'an University(300103714017).
文摘In this paper,the images of tunnel surface are obtained by tunnel lining rapid inspection system,and tunnel crack forest dataset(TCFD)is established.The disaster characteristics of tunnel cracks are analyzed and summarized.Solutions of tunnel crack segmentation(TCS)method are developed for the detection and recognition of cracks on tunnel lining.According to the image features of the tunnel lining and the optical principal of detection equipment,effective image pre-processing steps are carried out before crack extraction.The tunnel image of TCFD is divided into appropriate number of blocks to magnify the local features of tunnel cracks.Local threshold segmentation method is used to traverse the blocks successively,and the first target block with crack is obtained.The seed in the target block were obtained by adaptive localization method and mapped to the whole image.Region growing is performed through crack seed until complete tunnel crack is extracted.The results show that the precision,recall rate and F-measure of tunnel cracks under the TCS method can reach 92.58%,93.07%and 92.82%without strong interference.According to the binary images processed by TCS method,the projection images of different types of tunnel cracks and their respective laws are obtained.Furthermore,the TCS method is implemented and deployed as a GUI software application.
