Based on the working principle of satellite radars, the earthquake deformation field measured by interferometric synthetic aperture（InSAR） is the projection of ground displacement associated with the seismogenic fau...Based on the working principle of satellite radars, the earthquake deformation field measured by interferometric synthetic aperture（InSAR） is the projection of ground displacement associated with the seismogenic fault in the line of sight（LOS） of the satellite. However, LOS projections are complex, and are not only related to the ascending/descending modes and incidence angles of SAR data, but also related to the strike and motion senses of the fault. Even for the same earthquake, the LOS deformation derived from different ascending/descending data can be almost identical in one case, but quite different in another case, which makes the interpretation of InSAR seismic deformation and its comparison with field observations difficult. In this study, we undertook a quantitative analysis of the relationships between LOS observation sensitivity of InSAR and fault strike, fault motion sense, and ascending/descending modes, as well as 3D deformation fields. We studied the features and differences of the LOS deformation fields in different types of earthquakes using ascending/descending modes, with a particularly detailed analysis of the relations for a strikeslip type of earthquake. We also summarized the characteristics of LOS deformation fields of faults with different strikes and optimal observational data modes. Taking the strike-slip Yushu earthquake and the normal Gaize event as examples, we used SAR data of the ascending/descending modes to verify the results of quantitative calculations. These analyses will not only provide a more reasonable interpretation of InSAR seismic deformation fields and but also help understand the differences of seismic deformation fields revealed by data with different observational modes, therefore promoting the application of InSAR technology in seismology.展开更多
BACKGROUND Obesity is a risk factor for colorectal cancer,yet metabolic distinctions between healthy right and left colon tissue,before cancer is diagnosed,remains largely unknown.This study compared right-ascending a...BACKGROUND Obesity is a risk factor for colorectal cancer,yet metabolic distinctions between healthy right and left colon tissue,before cancer is diagnosed,remains largely unknown.This study compared right-ascending and left-descending colon tissue metabolomes to identify differences from the stool metabolome in normal weight,overweight,and obese adults.AIM To examine right and left colon tissue metabolites according to body mass index that may serve as mechanistic targets for interventions and biomarkers for colon cancer risk.METHODS Global,non-targeted metabolomics was applied to assess right-ascending and left-descending colon tissue collected from healthy adults undergoing screening colonoscopies to test the hypothesis that BMI differentially impacts colon tissue metabolite profiles.The colon tissue and stool metabolome of healthy adults(n=24)was analyzed for metabolite signatures and metabolic pathway networks implicated in progression of colorectal cancer.RESULTS Ascending and descending colon contained 504 host,food,and microbiotaderived metabolites from normal weight,overweight and obese adults grouped according to body mass index.Amino acids,lipids,and nucleotides were among the chemical types that further differentiated from the stool metabolite profiles.Normal weight adults had 46 significantly different metabolites between ascending and descending colon tissue locations,whereas there were 37 metabolite differences in overweight and 28 metabolite differences for obese adults(P<0.05).Obese adults had trimethylamine N-oxide,endocannabinoids and monoacylglycerols with different relative abundances identified between ascending and descending colon.Primary and secondary bile acids,vitamins,and fatty acids also showed marked relative abundance differences in colon tissue from overweight/obese adults.CONCLUSION There were metabolite profile differences between right-ascending and leftdescending colon tissue in healthy adults.Colon lipids and other metabolites in obese and overweight adults were distinguished from normal weight participants and associated with gut inflammation,nutrient absorption,and products of microbiota metabolism.展开更多
Sensory inputs stimulated by Zusanli（ST36） acupuncture in the abdomen are known to converge in the upper cervical cord. However, it is unclear whether these inputs are subsequently conveyed to the hypothalamic parav...Sensory inputs stimulated by Zusanli（ST36） acupuncture in the abdomen are known to converge in the upper cervical cord. However, it is unclear whether these inputs are subsequently conveyed to the hypothalamic paraventricular nucleus and what kind of afferent fibers are involved. We focused on the upper cervical cord, where afferent inputs converge, and detected c-fos expression in oxytocinergic neurons. We found that Zusanli acupuncture therapy effectively elevated intragastric pressure, but inhibited expression of c-fos in oxytocinergic neurons of the paraventricular nucleus in upper cervical cord injured rats. These Zusanli acupuncture effects remained even after complete dorsal cord transection. However, after complete transection of the spinal cord or dorsolateral funiculus, the effects were significantly attenuated and even disappeared. These findings suggest that the paraventricular nucleus is responsible for pooling and integrating signals from the Zusanli acupuncture and sensory information from the intragastric pressure variation, thereby contributing to the regulation of intragastric pressure. The upper cervical cord serves as the key link between ascending and descending pathways, which conveys afferent inputs to the paraventricular nucleus through the dorsolateral funiculus.展开更多
One-sided ascending or descending Synthetic Aperture Radar（SAR） stereoradargrammetry has limited accuracy of topographic mapping due to the short spatial baseline（-100 km） and small intersection angle. In order to...One-sided ascending or descending Synthetic Aperture Radar（SAR） stereoradargrammetry has limited accuracy of topographic mapping due to the short spatial baseline（-100 km） and small intersection angle. In order to improve the performance and reliability of generating digital elevation model（DEM） from spaceborne SAR radargrammetry, an exploration of two-sided stereoradargrammetry from the combination of ascending and descending orbits with geometric configuration of long spatial baseline（-1000 km） was conducted in this study. The slant-range geometry between SAR sensors to the earth surface and the Doppler positioning equations were employed to establish the stereoscopic intersection model. The measurement uncertainty of two-sided radargrammetric elevation was estimated on the basis of radar parallax of homogeneous points between input SAR images. Two stereo-pairs of ALOS/PALSAR（Advanced Land Observing Satellite/Phased Array type L-band Synthetic Aperture Radar） acquisitions with the orbital separation almost 1080 km over the west Sichuan foreland basin with rolling topography in southwestern China were employed in the study to obtain the up-to-date terrain data after the 2008 Wenchuan earthquake that hit this area. Thequantitative accuracy assessment of two-sided radargrammetric DEM was performed with reference to field GPS observations. The experimental results show that the elevation accuracy reaches 5.5 m without ground control points（GCPs） used, and the accuracy is further improved to 1.5 m with only one GPS GCP used as the least constraint. The theoretical analysis and testing results demonstrate that the twosided long baseline SAR radargrammetry from the ascending and descending orbits can be a very promising technical alternative for large-area and high accuracy topographic mapping.展开更多
To extract the high-quality DEM in complicated mountain areas,a DEM fusion method for ascending and descending orbit StereoSAR DEMs considering Synthetic Aperture Radar(SAR)echo intensity is proposed.After the analysi...To extract the high-quality DEM in complicated mountain areas,a DEM fusion method for ascending and descending orbit StereoSAR DEMs considering Synthetic Aperture Radar(SAR)echo intensity is proposed.After the analysis for the influence of terrain features and SAR side-looking imaging characteristics on radar echo intensity and DEM accuracy,four Terras AR-X images with the stripmap mode and the 3 m spatial resolution covering a certain area of Maoxian County,Sichuan Province,China,was selected as the experimental area.StereoSAR technology was used to extract the ascending orbit StereoSAR DEM and the descending orbit StereoSAR DEM,respectively,and the corresponding radar echo intensity map was calculated.Then,while comparing the radar echo intensity corresponding to the same point position,DEM fusion was carried out,and the accuracy of DEM before and after the fusion was analyzed with the ground points measured by GNSS-RTK as reference data.Finally,a high-quality DEM with a 3 m spatial resolution in the experimental area was obtained.The DEM accuracy was improved on all slopes,and the mean absolute deviation(MAD)improved to 4.798 m,the standard deviation(SD)improved to 6.087 m and the LE90 improved to 40.48 m.The experimental results indicate that the fusion method of highresolution ascending and descending orbit StereoSAR DEMs considering SAR echo intensity can effectively extract DEM with high accuracy and reliability,which can provide technical support for obtaining highquality terrain information in similar areas.展开更多
Through the method of literature mining,the classics of traditional Chinese medicine,materia medica works,medical cases and documents are studied.Based on common prescriptions for the treatment of diseases such as abn...Through the method of literature mining,the classics of traditional Chinese medicine,materia medica works,medical cases and documents are studied.Based on common prescriptions for the treatment of diseases such as abnormal Zang-fu viscera and qi movement,dysfunction,etc.,and combined with the theory of ascending and descending property of traditional Chinese medicine,the application of ascending and descending property of traditional Chinese medicine in clinical prescription compatibility and the factors affecting the application are summarized.The ascending and descending properties of traditional Chinese medicine have been widely used in prescription compatibility for the clinical treatment of impairment of purifying and descending function of the lung,spleen and stomach's ascending and descending disorders and heart-kidney noninteractionpatte.展开更多
Persistent ascending or descending mesocolon is an embryological anomaly that occurs during the final process of intestinal development in organogenesis.Specifically,the primitive dorsal mesocolon fails to fuse with t...Persistent ascending or descending mesocolon is an embryological anomaly that occurs during the final process of intestinal development in organogenesis.Specifically,the primitive dorsal mesocolon fails to fuse with the parietal peritoneum in the fifth month of gestation.Herein,we describe a case of ascending colon cancer with persistent ascending and descending mesocolon treated by laparoscopic right hemicolectomy.Preoperative computed tomography imaging of the abdomen demonstrated that the descending colon shifted at the midline of the abdomen and the sigmoid colon was located under the ascending colon.The detailed preoperative imaging examination revealed malpositioning of the large intestine and aided in the procedural planning.Because persistent mesocolon may result in the formation of abnormal adhesions,an accurate preoperative diagnosis is essential.We propose that it is important to consider this anomaly when making the preoperative imaging diagnosis to ensure a safe operation.展开更多
This article analyzes the shift factors of the descending node local time for sun-synchronous satellites and proposes a shift control method to keep the local time shift within an allowance range. It is found that the...This article analyzes the shift factors of the descending node local time for sun-synchronous satellites and proposes a shift control method to keep the local time shift within an allowance range. It is found that the satellite orbit design and the orbit injection deviation are the causes for the initial shift velocity, whereas the atmospheric drag and the sun gravitational perturbation produce the shift acceleration. To deal with these shift factors, a shift control method is put forward, through such methods as orbit variation design, orbit altitude, and inclination keeping control. The simulation experiment and practical application have proved the effectiveness of this control method.展开更多
基金jointly supported by projects of the National Key Laboratory for Earthquake Dynamics (LED2013A02,LED2015A03)the National Natural Science foundation of China (41374105)
文摘Based on the working principle of satellite radars, the earthquake deformation field measured by interferometric synthetic aperture（InSAR） is the projection of ground displacement associated with the seismogenic fault in the line of sight（LOS） of the satellite. However, LOS projections are complex, and are not only related to the ascending/descending modes and incidence angles of SAR data, but also related to the strike and motion senses of the fault. Even for the same earthquake, the LOS deformation derived from different ascending/descending data can be almost identical in one case, but quite different in another case, which makes the interpretation of InSAR seismic deformation and its comparison with field observations difficult. In this study, we undertook a quantitative analysis of the relationships between LOS observation sensitivity of InSAR and fault strike, fault motion sense, and ascending/descending modes, as well as 3D deformation fields. We studied the features and differences of the LOS deformation fields in different types of earthquakes using ascending/descending modes, with a particularly detailed analysis of the relations for a strikeslip type of earthquake. We also summarized the characteristics of LOS deformation fields of faults with different strikes and optimal observational data modes. Taking the strike-slip Yushu earthquake and the normal Gaize event as examples, we used SAR data of the ascending/descending modes to verify the results of quantitative calculations. These analyses will not only provide a more reasonable interpretation of InSAR seismic deformation fields and but also help understand the differences of seismic deformation fields revealed by data with different observational modes, therefore promoting the application of InSAR technology in seismology.
基金Supported by the Cancer Cure Foundation and the University of Colorado Cancer Center Support Grant,Division of Cancer Control and Prevention(Aurora,CO),No.P30CA046934
文摘BACKGROUND Obesity is a risk factor for colorectal cancer,yet metabolic distinctions between healthy right and left colon tissue,before cancer is diagnosed,remains largely unknown.This study compared right-ascending and left-descending colon tissue metabolomes to identify differences from the stool metabolome in normal weight,overweight,and obese adults.AIM To examine right and left colon tissue metabolites according to body mass index that may serve as mechanistic targets for interventions and biomarkers for colon cancer risk.METHODS Global,non-targeted metabolomics was applied to assess right-ascending and left-descending colon tissue collected from healthy adults undergoing screening colonoscopies to test the hypothesis that BMI differentially impacts colon tissue metabolite profiles.The colon tissue and stool metabolome of healthy adults(n=24)was analyzed for metabolite signatures and metabolic pathway networks implicated in progression of colorectal cancer.RESULTS Ascending and descending colon contained 504 host,food,and microbiotaderived metabolites from normal weight,overweight and obese adults grouped according to body mass index.Amino acids,lipids,and nucleotides were among the chemical types that further differentiated from the stool metabolite profiles.Normal weight adults had 46 significantly different metabolites between ascending and descending colon tissue locations,whereas there were 37 metabolite differences in overweight and 28 metabolite differences for obese adults(P<0.05).Obese adults had trimethylamine N-oxide,endocannabinoids and monoacylglycerols with different relative abundances identified between ascending and descending colon.Primary and secondary bile acids,vitamins,and fatty acids also showed marked relative abundance differences in colon tissue from overweight/obese adults.CONCLUSION There were metabolite profile differences between right-ascending and leftdescending colon tissue in healthy adults.Colon lipids and other metabolites in obese and overweight adults were distinguished from normal weight participants and associated with gut inflammation,nutrient absorption,and products of microbiota metabolism.
基金supported by the National Natural Science Foundation of China,No.81273677a grant from the Postgraduate Innovation Topics of Hunan University of Chinese Medicine in China in 2014,No.2014CX01
文摘Sensory inputs stimulated by Zusanli（ST36） acupuncture in the abdomen are known to converge in the upper cervical cord. However, it is unclear whether these inputs are subsequently conveyed to the hypothalamic paraventricular nucleus and what kind of afferent fibers are involved. We focused on the upper cervical cord, where afferent inputs converge, and detected c-fos expression in oxytocinergic neurons. We found that Zusanli acupuncture therapy effectively elevated intragastric pressure, but inhibited expression of c-fos in oxytocinergic neurons of the paraventricular nucleus in upper cervical cord injured rats. These Zusanli acupuncture effects remained even after complete dorsal cord transection. However, after complete transection of the spinal cord or dorsolateral funiculus, the effects were significantly attenuated and even disappeared. These findings suggest that the paraventricular nucleus is responsible for pooling and integrating signals from the Zusanli acupuncture and sensory information from the intragastric pressure variation, thereby contributing to the regulation of intragastric pressure. The upper cervical cord serves as the key link between ascending and descending pathways, which conveys afferent inputs to the paraventricular nucleus through the dorsolateral funiculus.
基金supported by the National Natural Science Foundation of China(Grant Nos.41472255,51178404)Open Research Fund by Sichuan Engineering Research Center for Emergency Mapping & Disaster Reduction(Program K2014B006)Fundamental Research Funds for the Central Universities(Grant Nos.SWJTU12ZT07,2682014BR014)
文摘One-sided ascending or descending Synthetic Aperture Radar（SAR） stereoradargrammetry has limited accuracy of topographic mapping due to the short spatial baseline（-100 km） and small intersection angle. In order to improve the performance and reliability of generating digital elevation model（DEM） from spaceborne SAR radargrammetry, an exploration of two-sided stereoradargrammetry from the combination of ascending and descending orbits with geometric configuration of long spatial baseline（-1000 km） was conducted in this study. The slant-range geometry between SAR sensors to the earth surface and the Doppler positioning equations were employed to establish the stereoscopic intersection model. The measurement uncertainty of two-sided radargrammetric elevation was estimated on the basis of radar parallax of homogeneous points between input SAR images. Two stereo-pairs of ALOS/PALSAR（Advanced Land Observing Satellite/Phased Array type L-band Synthetic Aperture Radar） acquisitions with the orbital separation almost 1080 km over the west Sichuan foreland basin with rolling topography in southwestern China were employed in the study to obtain the up-to-date terrain data after the 2008 Wenchuan earthquake that hit this area. Thequantitative accuracy assessment of two-sided radargrammetric DEM was performed with reference to field GPS observations. The experimental results show that the elevation accuracy reaches 5.5 m without ground control points（GCPs） used, and the accuracy is further improved to 1.5 m with only one GPS GCP used as the least constraint. The theoretical analysis and testing results demonstrate that the twosided long baseline SAR radargrammetry from the ascending and descending orbits can be a very promising technical alternative for large-area and high accuracy topographic mapping.
基金supported by Study on Early Identification of Landslide Hazards based on Highresolution SAR Image[KJ-2018-13]。
文摘To extract the high-quality DEM in complicated mountain areas,a DEM fusion method for ascending and descending orbit StereoSAR DEMs considering Synthetic Aperture Radar(SAR)echo intensity is proposed.After the analysis for the influence of terrain features and SAR side-looking imaging characteristics on radar echo intensity and DEM accuracy,four Terras AR-X images with the stripmap mode and the 3 m spatial resolution covering a certain area of Maoxian County,Sichuan Province,China,was selected as the experimental area.StereoSAR technology was used to extract the ascending orbit StereoSAR DEM and the descending orbit StereoSAR DEM,respectively,and the corresponding radar echo intensity map was calculated.Then,while comparing the radar echo intensity corresponding to the same point position,DEM fusion was carried out,and the accuracy of DEM before and after the fusion was analyzed with the ground points measured by GNSS-RTK as reference data.Finally,a high-quality DEM with a 3 m spatial resolution in the experimental area was obtained.The DEM accuracy was improved on all slopes,and the mean absolute deviation(MAD)improved to 4.798 m,the standard deviation(SD)improved to 6.087 m and the LE90 improved to 40.48 m.The experimental results indicate that the fusion method of highresolution ascending and descending orbit StereoSAR DEMs considering SAR echo intensity can effectively extract DEM with high accuracy and reliability,which can provide technical support for obtaining highquality terrain information in similar areas.
基金University-level Scientific Research Project of Guangxi University of Chinese Medicine(2015MS011)Guangxi Key Laboratory of Zhuang Yao Medicine(20-065-14)Key Laboratory of Basic and Applied Research of Zhuang Traditional Medicine in Collages and Universities in Guangxi(GJKY[2017]23 zyfy201707).
文摘Through the method of literature mining,the classics of traditional Chinese medicine,materia medica works,medical cases and documents are studied.Based on common prescriptions for the treatment of diseases such as abnormal Zang-fu viscera and qi movement,dysfunction,etc.,and combined with the theory of ascending and descending property of traditional Chinese medicine,the application of ascending and descending property of traditional Chinese medicine in clinical prescription compatibility and the factors affecting the application are summarized.The ascending and descending properties of traditional Chinese medicine have been widely used in prescription compatibility for the clinical treatment of impairment of purifying and descending function of the lung,spleen and stomach's ascending and descending disorders and heart-kidney noninteractionpatte.
文摘Persistent ascending or descending mesocolon is an embryological anomaly that occurs during the final process of intestinal development in organogenesis.Specifically,the primitive dorsal mesocolon fails to fuse with the parietal peritoneum in the fifth month of gestation.Herein,we describe a case of ascending colon cancer with persistent ascending and descending mesocolon treated by laparoscopic right hemicolectomy.Preoperative computed tomography imaging of the abdomen demonstrated that the descending colon shifted at the midline of the abdomen and the sigmoid colon was located under the ascending colon.The detailed preoperative imaging examination revealed malpositioning of the large intestine and aided in the procedural planning.Because persistent mesocolon may result in the formation of abnormal adhesions,an accurate preoperative diagnosis is essential.We propose that it is important to consider this anomaly when making the preoperative imaging diagnosis to ensure a safe operation.
基金supported by the China Postdotoral Science Foundation(20060401004)
文摘This article analyzes the shift factors of the descending node local time for sun-synchronous satellites and proposes a shift control method to keep the local time shift within an allowance range. It is found that the satellite orbit design and the orbit injection deviation are the causes for the initial shift velocity, whereas the atmospheric drag and the sun gravitational perturbation produce the shift acceleration. To deal with these shift factors, a shift control method is put forward, through such methods as orbit variation design, orbit altitude, and inclination keeping control. The simulation experiment and practical application have proved the effectiveness of this control method.
