For the ASO-S/HXI payload, the accuracy of the flare reconstruction is reliant on important factors such as the alignment of the dual grating and the precise measurement of observation orientation. To guarantee optima...For the ASO-S/HXI payload, the accuracy of the flare reconstruction is reliant on important factors such as the alignment of the dual grating and the precise measurement of observation orientation. To guarantee optimal functionality of the instrument throughout its life cycle, the Solar Aspect System (SAS) is imperative to ensure that measurements are accurate and reliable. This is achieved by capturing the target motion and utilizing a physical model-based inversion algorithm. However, the SAS optical system’s inversion model is a typical ill-posed inverse problem due to its optical parameters, which results in small target sampling errors triggering unacceptable shifts in the solution. To enhance inversion accuracy and make it more robust against observation errors, we suggest dividing the inversion operation into two stages based on the SAS spot motion model. First, the as-rigid-aspossible (ARAP) transformation algorithm calculates the relative rotations and an intermediate variable between the substrates. Second, we solve an inversion linear equation for the relative translation of the substrates, the offset of the optical axes, and the observation orientation. To address the ill-posed challenge, the Tikhonov method grounded on the discrepancy criterion and the maximum a posteriori (MAP) method founded on the Bayesian framework are utilized. The simulation results exhibit that the ARAP method achieves a solution with a rotational error of roughly±3 5 (1/2-quantile);both regularization techniques are successful in enhancing the stability of the solution, the variance of error in the MAP method is even smaller—it achieves a translational error of approximately±18μm (1/2-quantile) in comparison to the Tikhonov method’s error of around±24μm (1/2-quantile). Furthermore, the SAS practical application data indicates the method’s usability in this study. Lastly, this paper discusses the intrinsic interconnections between the regularization methods.展开更多
Acute appendicitis is a common surgical emergency.It is commonly caused by obstruction of the appendiceal lumen due to fecaliths,tumors,or lymphoid hyperplasia.For over a century,appendectomy has been the primary trea...Acute appendicitis is a common surgical emergency.It is commonly caused by obstruction of the appendiceal lumen due to fecaliths,tumors,or lymphoid hyperplasia.For over a century,appendectomy has been the primary treatment for acute appendicitis.Abraham Groves performed the first open appendectomy in 1883.In 1983,Kurt Semm completed the first laparoscopic appendectomy,heralding a new era in appendectomy.However,appendectomy is associated with certain complications and a rate of negative appendectomies.Studies have suggested controversy over the impact of appendectomy on the development of inflammatory bowel disease and Parkinson’s disease,but an increasing number of studies indicate a possible positive correlation between appendectomy and colorectal cancer,gallstones,and cardiovascular disease.With the recognition that the appendix is not a vestigial organ and the advancement of endoscopic technology,Liu proposed the endoscopic retrograde appendicitis therapy.It is an effective minimally invasive alternative for treating uncomplicated acute appendicitis.Our team has developed an appendoscope with a disposable digital imaging system operated through the biopsy channel of a colonoscope and successfully applied it in the treatment of appendicitis.This article provides an overview of the progress in endoscopic treatment for acute appendicitis and offers a new perspective on the future direction of appendiceal disease treatment.展开更多
The Advanced Space-based Solar Observatory(ASO-S)is a mission proposed for the 25 th solar maximum by the Chinese solar community.The scientific objectives are to study the relationships between the solar magnetic fie...The Advanced Space-based Solar Observatory(ASO-S)is a mission proposed for the 25 th solar maximum by the Chinese solar community.The scientific objectives are to study the relationships between the solar magnetic field,solar flares and coronal mass ejections(CMEs).Three payloads are deployed:the Full-disk vector Magneto Graph(FMG),the Lyman-αSolar Telescope(LST)and the Hard X-ray Imager(HXI).ASO-S will perform the first simultaneous observations of the photospheric vector magnetic field,non-thermal imaging of solar flares,and the initiation and early propagation of CMEs on a single platform.ASO-S is scheduled to be launched into a 720 km Sun-synchronous orbit in 2022.This paper presents an overview of the mission till the end of Phase-B and the beginning of Phase-C.展开更多
The Full-disk Magneto Graph(FMG),a payload onboard the Advanced Space Solar Observatory(ASO-S),will measure the vector magnetic field in the photosphere.The instrument consists of a frontwindow filter,a telescope,an L...The Full-disk Magneto Graph(FMG),a payload onboard the Advanced Space Solar Observatory(ASO-S),will measure the vector magnetic field in the photosphere.The instrument consists of a frontwindow filter,a telescope,an LCVR polarimeter,an image-stabilization system,a seven-stage tunable Lyot filter,a CMOS camera with 4096×4096 pixels and a pair of calibration/focus wheels.In this paper,we describe the design of the FMG instrument and provide a summary of test observations carried out with the FMG prototype.展开更多
AIM: To investigate the relationship between infiltrating inflammatory cell and tumor angiogenesis in hepatocellular carcinoma (HCC) tissues and their clinicopathological features.METHODS: The paraffin-embedded specim...AIM: To investigate the relationship between infiltrating inflammatory cell and tumor angiogenesis in hepatocellular carcinoma (HCC) tissues and their clinicopathological features.METHODS: The paraffin-embedded specimens from 70 cases with HCC were stained using EliVision immunohistochemistry with mAbs against CD68, tryptase,and CD34. The counts of tumor-associated macrophage (TAM), mast cell (MC) and tumor microvessel (MV) were performed in the tissue sections.RESULTS: The mean counts of TAM, MC, and MV in HCC tissues were significantly higher than those in pericarcinomatous liver tissues (TAM: 69.31± 11.58 vs 40.23±10.36; MC: 16.74±5.67 vs 7.59±4.18; MV:70.11±12.45 vs 38.52± 11.16, P<0.01). The MV count in the patients with metastasis was markedly higher than that with non-metastasis (P<0.01). In addition, the MC count in the patients with poorly differentiated HCC was obviously higher than that with well differentiated HCC (P< 0.01). The correlation analysis showed that the TAM count was significantly correlated with the count of MV(r=0.712, P<0.01), and the MC count was obviously correlated with the MV count (r= 0.336, P< 0.05).CONCLUSION: TAM and MC might be closely related to the enhancement of tumor angiogenesis. The MV count might be associated with tumor invasion and metastasis.Moreover, the MC count might be associated with tumor differentiation and prognosis of HCC.展开更多
Hard X-ray Imager(HXI)is one of the three scientific instruments onboard the Advanced Spacebased Solar Observatory(ASO-S)mission,which is proposed for the 25th solar maximum by the Chinese solar community.HXI is desig...Hard X-ray Imager(HXI)is one of the three scientific instruments onboard the Advanced Spacebased Solar Observatory(ASO-S)mission,which is proposed for the 25th solar maximum by the Chinese solar community.HXI is designed to investigate the non-thermal high-energy electrons accelerated in solar flares by providing images of solar flaring regions in the energy range from 30 keV to 200 keV.The imaging principle of HXI is based on spatially modulated Fourier synthesis and utilizes about 91 sets of bi-grid sub-collimators and corresponding LaBr3 detectors to obtain Fourier components with a spatial resolution of about 3 arcsec and a time resolution better than 0.5 s.An engineering prototype has been developed and tested to verify the feasibility of design.In this paper,we present background,instrument design and the development and test status of the prototype.展开更多
Primary gastric plasmacytoma (GP) is a rare extramedullary plasmacytoma with clinical and imaging features that are common among other gastric tumors, such as gastric adenocarcinomas, gastric stromal tumors, and lymph...Primary gastric plasmacytoma (GP) is a rare extramedullary plasmacytoma with clinical and imaging features that are common among other gastric tumors, such as gastric adenocarcinomas, gastric stromal tumors, and lymphomas. Here, we present a histologically confirmed case of primary GP examined with biphasic computed tomography (CT), magnetic resonance imaging (MRI), and endosonography. A well-circumscribed extraluminal mass appearing as homogeneous attenuation/intensity with gradual enhancement was identified on biphasic enhancement CT and MRI. This mass was hyperintense on diffusion-weighted imaging and hypointense on the apparent diffusion coefficient map, implying that water diffusion in the mass was restricted. In addition, endosonography indicated a low echogenic mass in the gastric wall. These imaging findings increase the available knowledge about imaging of this disease and provide valuable information for differentiating primary GP from common gastric tumors.展开更多
Heterotopic pancreas(HP) is a relatively uncommon entity that is defined as pancreatic tissue without a true anatomical or vascular connection to the pancreas. HP does not cause symptoms in most cases but can occasion...Heterotopic pancreas(HP) is a relatively uncommon entity that is defined as pancreatic tissue without a true anatomical or vascular connection to the pancreas. HP does not cause symptoms in most cases but can occasionally produce various manifestations, including nausea, vomiting, abdominal pain, and even heterotopic pancreatitis. Here, we report an unusual case in which heterotopic pancreatitis complicated by the formation of a pseudocyst that caused gastric outlet obstruction was diagnosed based on serum hyperamylasemia and findings from endoscopic ultrasonography(EUS)-guided fine needle aspiration(EUS-FNA) cytology. EUS-guided single pigtail stent insertion was successfully performed for recurrent gastric outlet obstruction. The patient has remained healthy and symptom-free during 4 years of surveillance. In the context of the relevant literature, the described case is a rare case of HP complicated by a pseudocyst treated via EUS-FNA and stent insertion.展开更多
AIM: To validate 4-sample lactose hydrogen breath testing(4SLHBT) compared to standard 13-sample LHBT in the clinical setting.METHODS: Irritable bowel syndrome patients with diarrhea(IBS-D) and healthy volunteers(HVs)...AIM: To validate 4-sample lactose hydrogen breath testing(4SLHBT) compared to standard 13-sample LHBT in the clinical setting.METHODS: Irritable bowel syndrome patients with diarrhea(IBS-D) and healthy volunteers(HVs) were enrolled and received a 10 g, 20 g, or 40 g doselactose hydrogen breath test(LHBT) in a randomized, double-blinded, controlled trial. The lactase gene promoter region was sequenced. Breath samples and symptoms were acquired at baseline and every 15 min for 3 h(13 measurements). The detection rates of lactose malabsorption(LM) and lactose intolerance(LI) for a 4SLHBT that acquired four measurements at 0, 90, 120, and 180 min from the same data set were compared with the results of standard LHBT.RESULTS: Sixty IBS-D patients and 60 HVs were studied. The genotype in all participants was C/C-13910. LM and LI detection rates increased with lactose dose from 10 g, 20 g to 40 g in both groups(P < 0.001). 4SLHBT showed excellent diagnostic concordance with standard LHBT(97%-100%, Kappa 0.815-0.942) with high sensitivity(90%-100%) and specificity(100%) at all three lactose doses in both groups.CONCLUSION: Reducing the number of measurements from 13 to 4 samples did not significantly impact on the accuracy of LHBT in health and IBS-D. 4SLHBT is a valid test for assessment of LM and LI in clinical practice.展开更多
AIM: To investigate the feasibility of a dual-input two-compartment tracer kinetic model for evaluating tumorous microvascular properties in advanced hepatocellular carcinoma(HCC). METHODS: From January 2014 to April ...AIM: To investigate the feasibility of a dual-input two-compartment tracer kinetic model for evaluating tumorous microvascular properties in advanced hepatocellular carcinoma(HCC). METHODS: From January 2014 to April 2015, we prospectively measured and analyzed pharmacokinetic parameters [transfer constant(K_(trans)), plasma flow(F_p), permeability surface area product(PS), efflux rate constant(k_(ep)), extravascular extracellular space volume ratio(V_e), blood plasma volume ratio(V_p), and hepatic perfusion index(HPI)] using dual-input two-compartment tracer kinetic models [a dual-input extended Tofts model and a dual-input 2-compartment exchange model(2CXM)] in 28 consecutive HCC patients. A well-known consensus that HCC is a hypervascular tumor supplied by the hepatic artery and the portal vein was used as a reference standard. A paired Student's t-test and a nonparametric paired Wilcoxon rank sum test were used to compare the equivalent pharmacokinetic parameters derived from the two models, and Pearson correlation analysis was also applied to observe the correlations among all equivalent parameters. The tumor size and pharmacokinetic parameters were tested by Pearson correlation analysis, while correlations among stage, tumor size and all pharmacokinetic parameters were assessed by Spearman correlation analysis. RESULTS: The F_p value was greater than the PS value(F_P = 1.07 m L/m L per minute, PS = 0.19 m L/m L per minute) in the dual-input 2CXM; HPI was 0.66 and 0.63 in the dual-input extended Tofts model and the dualinput 2CXM, respectively. There were no significant differences in the K_(ep), V_p, or HPI between the dual-input extended Tofts model and the dual-input 2CXM(P = 0.524, 0.569, and 0.622, respectively). All equivalent pharmacokinetic parameters, except for V_e, were correlated in the two dual-input two-compartment pharmacokinetic models; both Fp and PS in the dualinput 2CXM were correlated with K_(trans) derived from the dual-input extended Tofts model(P = 0.002, r = 0.566; P = 0.002, r = 0.570); K_(ep), V_p, and HPI between the two kinetic models were positively correlated(P = 0.001, r = 0.594; P = 0.0001, r = 0.686; P = 0.04, r = 0.391, respectively). In the dual input extended Tofts model, V_e was significantly less than that in the dual input 2CXM(P = 0.004), and no significant correlation was seen between the two tracer kinetic models(P = 0.156, r = 0.276). Neither tumor size nor tumor stage was significantly correlated with any of the pharmacokinetic parameters obtained from the two models(P > 0.05).CONCLUSION: A dual-input two-compartment pharmacokinetic model(a dual-input extended Tofts model and a dual-input 2CXM) can be used in assessing the microvascular physiopathological properties before the treatment of advanced HCC. The dual-input extended Tofts model may be more stable in measuring the V_e; however, the dual-input 2CXM may be more detailed and accurate in measuring microvascular permeability.展开更多
BACKGROUND Pancreaticobiliary maljunction(PBM) is an uncommon congenital anomaly of the pancreatic and biliary ductal system, defined as a union of the pancreatic and biliary ducts located outside the duodenal wall. A...BACKGROUND Pancreaticobiliary maljunction(PBM) is an uncommon congenital anomaly of the pancreatic and biliary ductal system, defined as a union of the pancreatic and biliary ducts located outside the duodenal wall. According to the Komi classification of PBM, the common bile duct(CBD) directly fuses with the ventral pancreatic duct in all types. Pancreas divisum(PD) occurs when the ventral and dorsal ducts of the embryonic pancreas fail to fuse during the second month of fetal development. The coexistence of PBM and PD is an infrequent condition.Here, we report an unusual variant of PBM associated with PD in a pediatric patient, in whom an anomalous communication existed between the CBD and dorsal pancreatic duct.CASE SUMMARY A boy aged 4 years and 2 mo was hospitalized for abdominal pain with nausea and jaundice for 5 d. Abdominal ultrasound showed cholecystitis with cholestasis in the gallbladder, dilated middle-upper CBD, and a strong echo in the lower CBD, indicating biliary stones. The diagnosis was extrahepatic biliary obstruction caused by biliary stones, which is an indication for endoscopic retrograde cholangiopancreatography(ERCP). ERCP was performed to remove biliary stones. During the ERCP, we found a rare communication between the CBD and dorsal pancreatic duct. After clearing the CBD with a balloon, an 8.5 Fr 4-cm pigtail plastic pancreatic stent was placed in the biliary duct through the major papilla. Six months later, his biliary stent was removed after he had no symptoms and normal laboratory tests. In the following 4-year period, the child grew up normally with no more attacks of abdominal pain.CONCLUSION We consider that ERCP is effective and safe in pediatric patients with PBM combined with PD, and can be the initial therapy to manage such cases,especially when it is combined with aberrant communication between the CBD and dorsal pancreatic duct.展开更多
AIM to compare the efficacy and safety of a hook knife(HO) with a hybrid knife(HK) during endoscopic submucosal tunnel dissection(EStD) procedure.METHODS Between August 2012 and December 2015, the ESt D procedure was ...AIM to compare the efficacy and safety of a hook knife(HO) with a hybrid knife(HK) during endoscopic submucosal tunnel dissection(EStD) procedure.METHODS Between August 2012 and December 2015, the ESt D procedure was performed for 83 upper GI submucosal lesions, which originated from the muscularis propria layer identified by upper endoscopy and endoscopic ultrasonography. Of these, 34 lesions were treated by a HO, whereas 49 lesions were treated by a HK. Data regarding age, gender, presenting symptoms, tumor location and size, procedure time, complications, en bloc resection rate and others were analyzed and compared between the two groups.RESULTS there were no significant differences in the age, gender, presenting symptoms and tumor location between the two groups. EStD was successfully completed in all the patients, and no case was converted to laparoscopy. the mean procedure time was significantly shorter in the HK group than in the HO group(41.3 ± 20.3 min vs 57.2 ± 28.0 min, p = 0.004). the mean frequency of device exchange was 1.4 ± 0.6 in the HK group and significantly less than 3.3 ± 0.6 in the HO group(p < 0.001). the differences in tumor size and histopathological diagnoses were not significant between the two groups(p = 0.813, p = 0.363, respectively). Both groups had an equal en bloc resection rate and complete resection rate. Additionally, the complication rate was similar between the two groups(p = 0.901). During the follow-up, no recurrence occurred in either group.CONCLUSION We demonstrate for the first time that HO and HK do not differ in efficacy or safety, but HK reduces the frequency of device exchange and procedure time.展开更多
The terrain camera (TCAM) and panoramic camera (PCAM) are two of the major scientific payloads installed on the lander and rover of the Chang'e 3 mission re- spectively. They both use a Bayer color filter array c...The terrain camera (TCAM) and panoramic camera (PCAM) are two of the major scientific payloads installed on the lander and rover of the Chang'e 3 mission re- spectively. They both use a Bayer color filter array covering CMOS sensor to capture color images of the Moon's surface. RGB values of the original images are related to these two kinds of cameras. There is an obvious color difference compared with human visual perception. This paper follows standards published by the International Commission on Illumination to establish a color correction model, designs the ground calibration experiment and obtains the color correction coefficient. The image qual- ity has been significantly improved and there is no obvious color difference in the corrected images. Ground experimental results show that: (1) Compared with uncor- rected images, the average color difference of TCAM is 4.30, which has been reduced by 62.1%. (2) The average color differences of the left and right cameras in PCAM are 4.14 and 4.16, which have been reduced by 68.3% and 67.6% respectively.展开更多
A space-borne hard X-ray collimator,comprising 91 pairs of grids,has been developed for the Hard X-ray Imager(HXI).The HXI is one of the three scientific instruments onboard the first Chinese solar mission:the Advance...A space-borne hard X-ray collimator,comprising 91 pairs of grids,has been developed for the Hard X-ray Imager(HXI).The HXI is one of the three scientific instruments onboard the first Chinese solar mission:the Advanced Space-based Solar Observatory(ASO-S).The HXI collimator(HXI-C)is a spatial modulation X-ray telescope designed to observe hard X-rays emitted by energetic electrons in solar flares.This paper presents the detailed design of the HXI-C for the qualification model that will be inherited by the flight model.Series tests on the HXI-C qualification model are reported to verify the ability of the HXI-C to survive the launch and to operate normally in on-orbit environments.Furthermore,results of the X-ray beam test for the HXI-C are presented to indirectly identify the working performance of the HXI-C.展开更多
Endoscopic pancreatic stenting has been widely used in various pancreatic conditions. With the increasing use of pancreatic stents, many complications have been recognized. Especially, proximal stent migration present...Endoscopic pancreatic stenting has been widely used in various pancreatic conditions. With the increasing use of pancreatic stents, many complications have been recognized. Especially, proximal stent migration presents a serious condition because of subsequent pancreatic duct obstruction, impaired drainage, ductal dilation, and pancreatic pain. Although endoscopic retrieval is the preferred treatment for proximally migrated pancreatic stents, it is not always successful, resulting in conversion to surgery. To date, endoscopic ultrasound-guided pancreatic duct drainage(EUS-PD) has never been reported for treatment of pancreatic duct obstruction caused by proximally migrated pancreatic stent. We herein describe a case of pancreatic duct rupture and obstruction caused by proximally migrated pancreatic stent that was successfully treated by EUS-guided pancreaticogastrostomy while keeping the former stent in situ after failed endoscopic retrograde cholangiopancreatography. We believe that this report adds to the increasing evidence of symptomatic pancreatic duct obstruction being successfully treated by EUS-PD.展开更多
In the first half year of 2018,there were changes in China's economic,industrial structure and the changes in government's policy on land and mineral resources.China's geological exploration is continued t...In the first half year of 2018,there were changes in China's economic,industrial structure and the changes in government's policy on land and mineral resources.China's geological exploration is continued to maintain a trend of the growth.The fund investment in geological exploration declined and the impetus for investment in initial exploration was insufficient.The mining market showed a good development trend and the social investment depicted a slight rise.In the first half of the year,the investments in hydrogeologic exploration,environmental geology exploration and geological disaster investigation increased on the year-onyear basis.展开更多
Reaction-bonded B_(4)C–SiC composites are highly promising materials for numerous advanced technological applications.However,their microstructure evolution mechanism remains unclear.Herein,B_(4)C–SiC composites wer...Reaction-bonded B_(4)C–SiC composites are highly promising materials for numerous advanced technological applications.However,their microstructure evolution mechanism remains unclear.Herein,B_(4)C–SiC composites were fabricated through the Si-melt infiltration process.The influences of the sintering time and the B_(4)C content on the mechanical properties,microstructure,and phase evolution were investigated.X-ray diffraction results showed the presence of SiC,boron silicon,boron silicon carbide,and boron carbide.Scanning electron microscopy results showed that with the increase in the boron carbide content,the Si content decreased and the unreacted B_(4)C amount increased when the sintering temperature reached 1650°C and the sintering time reached 1 h.The unreacted B_(4)C diminished with increasing sintering time and temperature when B_(4)C content was lower than 35wt%.Further microstructure analysis showed a transition area between B_(4)C and Si,with the C content marginally higher than in the Si area.This indicates that after the silicon infiltration,the diffusion mechanism was the primary sintering mechanism of the composites.As the diffusion process progressed,the hardness increased.The maximum values of the Vickers hardness,flexural strength,and fracture toughness of the reaction-bonded B_(4)C–SiC ceramic composite with 12wt%B_(4)C content sintered at 1600°C for 0.5 h were about HV 2400,330 MPa,and 5.2 MPa·m^(0.5),respectively.展开更多
基金the Strategic Priority Research Program on Space Science of the Chinese Academy of Sciences,the grant No.XDA15320104,with additional contributions from the Purple Mountain Observatory(PMO)of the Chinese Academy of Sciences and the National Space Science Center(NSSC).
文摘For the ASO-S/HXI payload, the accuracy of the flare reconstruction is reliant on important factors such as the alignment of the dual grating and the precise measurement of observation orientation. To guarantee optimal functionality of the instrument throughout its life cycle, the Solar Aspect System (SAS) is imperative to ensure that measurements are accurate and reliable. This is achieved by capturing the target motion and utilizing a physical model-based inversion algorithm. However, the SAS optical system’s inversion model is a typical ill-posed inverse problem due to its optical parameters, which results in small target sampling errors triggering unacceptable shifts in the solution. To enhance inversion accuracy and make it more robust against observation errors, we suggest dividing the inversion operation into two stages based on the SAS spot motion model. First, the as-rigid-aspossible (ARAP) transformation algorithm calculates the relative rotations and an intermediate variable between the substrates. Second, we solve an inversion linear equation for the relative translation of the substrates, the offset of the optical axes, and the observation orientation. To address the ill-posed challenge, the Tikhonov method grounded on the discrepancy criterion and the maximum a posteriori (MAP) method founded on the Bayesian framework are utilized. The simulation results exhibit that the ARAP method achieves a solution with a rotational error of roughly±3 5 (1/2-quantile);both regularization techniques are successful in enhancing the stability of the solution, the variance of error in the MAP method is even smaller—it achieves a translational error of approximately±18μm (1/2-quantile) in comparison to the Tikhonov method’s error of around±24μm (1/2-quantile). Furthermore, the SAS practical application data indicates the method’s usability in this study. Lastly, this paper discusses the intrinsic interconnections between the regularization methods.
基金Supported by the Construction Fund of Key Medical Disciplines of Hangzhou,No.0020200026Key R&D Program of Zhejiang Province,No.2023C03054.
文摘Acute appendicitis is a common surgical emergency.It is commonly caused by obstruction of the appendiceal lumen due to fecaliths,tumors,or lymphoid hyperplasia.For over a century,appendectomy has been the primary treatment for acute appendicitis.Abraham Groves performed the first open appendectomy in 1883.In 1983,Kurt Semm completed the first laparoscopic appendectomy,heralding a new era in appendectomy.However,appendectomy is associated with certain complications and a rate of negative appendectomies.Studies have suggested controversy over the impact of appendectomy on the development of inflammatory bowel disease and Parkinson’s disease,but an increasing number of studies indicate a possible positive correlation between appendectomy and colorectal cancer,gallstones,and cardiovascular disease.With the recognition that the appendix is not a vestigial organ and the advancement of endoscopic technology,Liu proposed the endoscopic retrograde appendicitis therapy.It is an effective minimally invasive alternative for treating uncomplicated acute appendicitis.Our team has developed an appendoscope with a disposable digital imaging system operated through the biopsy channel of a colonoscope and successfully applied it in the treatment of appendicitis.This article provides an overview of the progress in endoscopic treatment for acute appendicitis and offers a new perspective on the future direction of appendiceal disease treatment.
基金supported by the Strategic Priority Research Program on Space Science, Chinese Academy of Sciences (Grant Nos. XDA15320100, XDA15320102, XDA15320103, XDA15320104, XDA15320300 and XDA15052200)supported by the National Natural Science Foundation of China (Grant Nos. 11427803, U1731241, U1631242 and 11820101002)
文摘The Advanced Space-based Solar Observatory(ASO-S)is a mission proposed for the 25 th solar maximum by the Chinese solar community.The scientific objectives are to study the relationships between the solar magnetic field,solar flares and coronal mass ejections(CMEs).Three payloads are deployed:the Full-disk vector Magneto Graph(FMG),the Lyman-αSolar Telescope(LST)and the Hard X-ray Imager(HXI).ASO-S will perform the first simultaneous observations of the photospheric vector magnetic field,non-thermal imaging of solar flares,and the initiation and early propagation of CMEs on a single platform.ASO-S is scheduled to be launched into a 720 km Sun-synchronous orbit in 2022.This paper presents an overview of the mission till the end of Phase-B and the beginning of Phase-C.
基金China Aerospace Science and Technology Corporation, the NO.771 InstituteChina Academy of Engineering Physics+4 种基金Changchun Institute of Optics, Fine Mechanics and Physics, CASNational Space Science Center, CASShanghai Engineering Center for Microsatellites, CASPurple Mountain Observatory, CASsupported by Grants:XDA15320102, 11427901 and XDA15052200
文摘The Full-disk Magneto Graph(FMG),a payload onboard the Advanced Space Solar Observatory(ASO-S),will measure the vector magnetic field in the photosphere.The instrument consists of a frontwindow filter,a telescope,an LCVR polarimeter,an image-stabilization system,a seven-stage tunable Lyot filter,a CMOS camera with 4096×4096 pixels and a pair of calibration/focus wheels.In this paper,we describe the design of the FMG instrument and provide a summary of test observations carried out with the FMG prototype.
基金Supported by the Hunan Provincial Natural Science Foundation of China,No.03-JJY5031
文摘AIM: To investigate the relationship between infiltrating inflammatory cell and tumor angiogenesis in hepatocellular carcinoma (HCC) tissues and their clinicopathological features.METHODS: The paraffin-embedded specimens from 70 cases with HCC were stained using EliVision immunohistochemistry with mAbs against CD68, tryptase,and CD34. The counts of tumor-associated macrophage (TAM), mast cell (MC) and tumor microvessel (MV) were performed in the tissue sections.RESULTS: The mean counts of TAM, MC, and MV in HCC tissues were significantly higher than those in pericarcinomatous liver tissues (TAM: 69.31± 11.58 vs 40.23±10.36; MC: 16.74±5.67 vs 7.59±4.18; MV:70.11±12.45 vs 38.52± 11.16, P<0.01). The MV count in the patients with metastasis was markedly higher than that with non-metastasis (P<0.01). In addition, the MC count in the patients with poorly differentiated HCC was obviously higher than that with well differentiated HCC (P< 0.01). The correlation analysis showed that the TAM count was significantly correlated with the count of MV(r=0.712, P<0.01), and the MC count was obviously correlated with the MV count (r= 0.336, P< 0.05).CONCLUSION: TAM and MC might be closely related to the enhancement of tumor angiogenesis. The MV count might be associated with tumor invasion and metastasis.Moreover, the MC count might be associated with tumor differentiation and prognosis of HCC.
基金supported by the Strategic Priority Research Program on Space Science, Chinese Academy of Sciences (Grant No. XDA15320104)the National Natural Science Foundation of China (Grant Nos. 11427803, 11622327, 11703079, 11803093 and 11820101002)
文摘Hard X-ray Imager(HXI)is one of the three scientific instruments onboard the Advanced Spacebased Solar Observatory(ASO-S)mission,which is proposed for the 25th solar maximum by the Chinese solar community.HXI is designed to investigate the non-thermal high-energy electrons accelerated in solar flares by providing images of solar flaring regions in the energy range from 30 keV to 200 keV.The imaging principle of HXI is based on spatially modulated Fourier synthesis and utilizes about 91 sets of bi-grid sub-collimators and corresponding LaBr3 detectors to obtain Fourier components with a spatial resolution of about 3 arcsec and a time resolution better than 0.5 s.An engineering prototype has been developed and tested to verify the feasibility of design.In this paper,we present background,instrument design and the development and test status of the prototype.
基金Supported by The Research Projects of Public Technology Application of Science and Technology of Shaoxing City,No.2013B70080
文摘Primary gastric plasmacytoma (GP) is a rare extramedullary plasmacytoma with clinical and imaging features that are common among other gastric tumors, such as gastric adenocarcinomas, gastric stromal tumors, and lymphomas. Here, we present a histologically confirmed case of primary GP examined with biphasic computed tomography (CT), magnetic resonance imaging (MRI), and endosonography. A well-circumscribed extraluminal mass appearing as homogeneous attenuation/intensity with gradual enhancement was identified on biphasic enhancement CT and MRI. This mass was hyperintense on diffusion-weighted imaging and hypointense on the apparent diffusion coefficient map, implying that water diffusion in the mass was restricted. In addition, endosonography indicated a low echogenic mass in the gastric wall. These imaging findings increase the available knowledge about imaging of this disease and provide valuable information for differentiating primary GP from common gastric tumors.
文摘Heterotopic pancreas(HP) is a relatively uncommon entity that is defined as pancreatic tissue without a true anatomical or vascular connection to the pancreas. HP does not cause symptoms in most cases but can occasionally produce various manifestations, including nausea, vomiting, abdominal pain, and even heterotopic pancreatitis. Here, we report an unusual case in which heterotopic pancreatitis complicated by the formation of a pseudocyst that caused gastric outlet obstruction was diagnosed based on serum hyperamylasemia and findings from endoscopic ultrasonography(EUS)-guided fine needle aspiration(EUS-FNA) cytology. EUS-guided single pigtail stent insertion was successfully performed for recurrent gastric outlet obstruction. The patient has remained healthy and symptom-free during 4 years of surveillance. In the context of the relevant literature, the described case is a rare case of HP complicated by a pseudocyst treated via EUS-FNA and stent insertion.
基金Supported by Nestle Research International and The Science and Technology Department of Zhejiang Province,No.2009C14016
文摘AIM: To validate 4-sample lactose hydrogen breath testing(4SLHBT) compared to standard 13-sample LHBT in the clinical setting.METHODS: Irritable bowel syndrome patients with diarrhea(IBS-D) and healthy volunteers(HVs) were enrolled and received a 10 g, 20 g, or 40 g doselactose hydrogen breath test(LHBT) in a randomized, double-blinded, controlled trial. The lactase gene promoter region was sequenced. Breath samples and symptoms were acquired at baseline and every 15 min for 3 h(13 measurements). The detection rates of lactose malabsorption(LM) and lactose intolerance(LI) for a 4SLHBT that acquired four measurements at 0, 90, 120, and 180 min from the same data set were compared with the results of standard LHBT.RESULTS: Sixty IBS-D patients and 60 HVs were studied. The genotype in all participants was C/C-13910. LM and LI detection rates increased with lactose dose from 10 g, 20 g to 40 g in both groups(P < 0.001). 4SLHBT showed excellent diagnostic concordance with standard LHBT(97%-100%, Kappa 0.815-0.942) with high sensitivity(90%-100%) and specificity(100%) at all three lactose doses in both groups.CONCLUSION: Reducing the number of measurements from 13 to 4 samples did not significantly impact on the accuracy of LHBT in health and IBS-D. 4SLHBT is a valid test for assessment of LM and LI in clinical practice.
基金Supported by Public Welfare Projects of Science Technology Department of Zhejiang Province,No.2014C33151Medical Research Programs of Zhejiang province,No.2014KYA215,No.2015KYB398,No.2015RCA024 and No.2015KYB403Research Projects of Public Technology Application of Science and Technology of Shaoxing City,No.2013D10039
文摘AIM: To investigate the feasibility of a dual-input two-compartment tracer kinetic model for evaluating tumorous microvascular properties in advanced hepatocellular carcinoma(HCC). METHODS: From January 2014 to April 2015, we prospectively measured and analyzed pharmacokinetic parameters [transfer constant(K_(trans)), plasma flow(F_p), permeability surface area product(PS), efflux rate constant(k_(ep)), extravascular extracellular space volume ratio(V_e), blood plasma volume ratio(V_p), and hepatic perfusion index(HPI)] using dual-input two-compartment tracer kinetic models [a dual-input extended Tofts model and a dual-input 2-compartment exchange model(2CXM)] in 28 consecutive HCC patients. A well-known consensus that HCC is a hypervascular tumor supplied by the hepatic artery and the portal vein was used as a reference standard. A paired Student's t-test and a nonparametric paired Wilcoxon rank sum test were used to compare the equivalent pharmacokinetic parameters derived from the two models, and Pearson correlation analysis was also applied to observe the correlations among all equivalent parameters. The tumor size and pharmacokinetic parameters were tested by Pearson correlation analysis, while correlations among stage, tumor size and all pharmacokinetic parameters were assessed by Spearman correlation analysis. RESULTS: The F_p value was greater than the PS value(F_P = 1.07 m L/m L per minute, PS = 0.19 m L/m L per minute) in the dual-input 2CXM; HPI was 0.66 and 0.63 in the dual-input extended Tofts model and the dualinput 2CXM, respectively. There were no significant differences in the K_(ep), V_p, or HPI between the dual-input extended Tofts model and the dual-input 2CXM(P = 0.524, 0.569, and 0.622, respectively). All equivalent pharmacokinetic parameters, except for V_e, were correlated in the two dual-input two-compartment pharmacokinetic models; both Fp and PS in the dualinput 2CXM were correlated with K_(trans) derived from the dual-input extended Tofts model(P = 0.002, r = 0.566; P = 0.002, r = 0.570); K_(ep), V_p, and HPI between the two kinetic models were positively correlated(P = 0.001, r = 0.594; P = 0.0001, r = 0.686; P = 0.04, r = 0.391, respectively). In the dual input extended Tofts model, V_e was significantly less than that in the dual input 2CXM(P = 0.004), and no significant correlation was seen between the two tracer kinetic models(P = 0.156, r = 0.276). Neither tumor size nor tumor stage was significantly correlated with any of the pharmacokinetic parameters obtained from the two models(P > 0.05).CONCLUSION: A dual-input two-compartment pharmacokinetic model(a dual-input extended Tofts model and a dual-input 2CXM) can be used in assessing the microvascular physiopathological properties before the treatment of advanced HCC. The dual-input extended Tofts model may be more stable in measuring the V_e; however, the dual-input 2CXM may be more detailed and accurate in measuring microvascular permeability.
文摘BACKGROUND Pancreaticobiliary maljunction(PBM) is an uncommon congenital anomaly of the pancreatic and biliary ductal system, defined as a union of the pancreatic and biliary ducts located outside the duodenal wall. According to the Komi classification of PBM, the common bile duct(CBD) directly fuses with the ventral pancreatic duct in all types. Pancreas divisum(PD) occurs when the ventral and dorsal ducts of the embryonic pancreas fail to fuse during the second month of fetal development. The coexistence of PBM and PD is an infrequent condition.Here, we report an unusual variant of PBM associated with PD in a pediatric patient, in whom an anomalous communication existed between the CBD and dorsal pancreatic duct.CASE SUMMARY A boy aged 4 years and 2 mo was hospitalized for abdominal pain with nausea and jaundice for 5 d. Abdominal ultrasound showed cholecystitis with cholestasis in the gallbladder, dilated middle-upper CBD, and a strong echo in the lower CBD, indicating biliary stones. The diagnosis was extrahepatic biliary obstruction caused by biliary stones, which is an indication for endoscopic retrograde cholangiopancreatography(ERCP). ERCP was performed to remove biliary stones. During the ERCP, we found a rare communication between the CBD and dorsal pancreatic duct. After clearing the CBD with a balloon, an 8.5 Fr 4-cm pigtail plastic pancreatic stent was placed in the biliary duct through the major papilla. Six months later, his biliary stent was removed after he had no symptoms and normal laboratory tests. In the following 4-year period, the child grew up normally with no more attacks of abdominal pain.CONCLUSION We consider that ERCP is effective and safe in pediatric patients with PBM combined with PD, and can be the initial therapy to manage such cases,especially when it is combined with aberrant communication between the CBD and dorsal pancreatic duct.
文摘AIM to compare the efficacy and safety of a hook knife(HO) with a hybrid knife(HK) during endoscopic submucosal tunnel dissection(EStD) procedure.METHODS Between August 2012 and December 2015, the ESt D procedure was performed for 83 upper GI submucosal lesions, which originated from the muscularis propria layer identified by upper endoscopy and endoscopic ultrasonography. Of these, 34 lesions were treated by a HO, whereas 49 lesions were treated by a HK. Data regarding age, gender, presenting symptoms, tumor location and size, procedure time, complications, en bloc resection rate and others were analyzed and compared between the two groups.RESULTS there were no significant differences in the age, gender, presenting symptoms and tumor location between the two groups. EStD was successfully completed in all the patients, and no case was converted to laparoscopy. the mean procedure time was significantly shorter in the HK group than in the HO group(41.3 ± 20.3 min vs 57.2 ± 28.0 min, p = 0.004). the mean frequency of device exchange was 1.4 ± 0.6 in the HK group and significantly less than 3.3 ± 0.6 in the HO group(p < 0.001). the differences in tumor size and histopathological diagnoses were not significant between the two groups(p = 0.813, p = 0.363, respectively). Both groups had an equal en bloc resection rate and complete resection rate. Additionally, the complication rate was similar between the two groups(p = 0.901). During the follow-up, no recurrence occurred in either group.CONCLUSION We demonstrate for the first time that HO and HK do not differ in efficacy or safety, but HK reduces the frequency of device exchange and procedure time.
基金Supported by the National Natural Science Foundation of China
文摘The terrain camera (TCAM) and panoramic camera (PCAM) are two of the major scientific payloads installed on the lander and rover of the Chang'e 3 mission re- spectively. They both use a Bayer color filter array covering CMOS sensor to capture color images of the Moon's surface. RGB values of the original images are related to these two kinds of cameras. There is an obvious color difference compared with human visual perception. This paper follows standards published by the International Commission on Illumination to establish a color correction model, designs the ground calibration experiment and obtains the color correction coefficient. The image qual- ity has been significantly improved and there is no obvious color difference in the corrected images. Ground experimental results show that: (1) Compared with uncor- rected images, the average color difference of TCAM is 4.30, which has been reduced by 62.1%. (2) The average color differences of the left and right cameras in PCAM are 4.14 and 4.16, which have been reduced by 68.3% and 67.6% respectively.
基金supported by the Strategic Priority Research Program on Space Science,Chinese Academy of Sciences(No.XDA 15320104)the National Natural Science Foundation of China(Grant Nos.11803093,11973097 and 12022302)the Scientific Instrument Developing Project of the CAS(No.20200077)。
文摘A space-borne hard X-ray collimator,comprising 91 pairs of grids,has been developed for the Hard X-ray Imager(HXI).The HXI is one of the three scientific instruments onboard the first Chinese solar mission:the Advanced Space-based Solar Observatory(ASO-S).The HXI collimator(HXI-C)is a spatial modulation X-ray telescope designed to observe hard X-rays emitted by energetic electrons in solar flares.This paper presents the detailed design of the HXI-C for the qualification model that will be inherited by the flight model.Series tests on the HXI-C qualification model are reported to verify the ability of the HXI-C to survive the launch and to operate normally in on-orbit environments.Furthermore,results of the X-ray beam test for the HXI-C are presented to indirectly identify the working performance of the HXI-C.
文摘Endoscopic pancreatic stenting has been widely used in various pancreatic conditions. With the increasing use of pancreatic stents, many complications have been recognized. Especially, proximal stent migration presents a serious condition because of subsequent pancreatic duct obstruction, impaired drainage, ductal dilation, and pancreatic pain. Although endoscopic retrieval is the preferred treatment for proximally migrated pancreatic stents, it is not always successful, resulting in conversion to surgery. To date, endoscopic ultrasound-guided pancreatic duct drainage(EUS-PD) has never been reported for treatment of pancreatic duct obstruction caused by proximally migrated pancreatic stent. We herein describe a case of pancreatic duct rupture and obstruction caused by proximally migrated pancreatic stent that was successfully treated by EUS-guided pancreaticogastrostomy while keeping the former stent in situ after failed endoscopic retrograde cholangiopancreatography. We believe that this report adds to the increasing evidence of symptomatic pancreatic duct obstruction being successfully treated by EUS-PD.
文摘In the first half year of 2018,there were changes in China's economic,industrial structure and the changes in government's policy on land and mineral resources.China's geological exploration is continued to maintain a trend of the growth.The fund investment in geological exploration declined and the impetus for investment in initial exploration was insufficient.The mining market showed a good development trend and the social investment depicted a slight rise.In the first half of the year,the investments in hydrogeologic exploration,environmental geology exploration and geological disaster investigation increased on the year-onyear basis.
基金financially supported by the National Natural Science Foundation of China(No.51875222)the China Postdoctoral Science Foundation(No.2017M622426)+1 种基金the First Class Special Funding for Postdoctoral Scientific Research of Hubei Province,China(No.2017-G3)the Opening Fund of State key laboratory for Environmentfriendly Energy Materials(No.17kffk 12)。
文摘Reaction-bonded B_(4)C–SiC composites are highly promising materials for numerous advanced technological applications.However,their microstructure evolution mechanism remains unclear.Herein,B_(4)C–SiC composites were fabricated through the Si-melt infiltration process.The influences of the sintering time and the B_(4)C content on the mechanical properties,microstructure,and phase evolution were investigated.X-ray diffraction results showed the presence of SiC,boron silicon,boron silicon carbide,and boron carbide.Scanning electron microscopy results showed that with the increase in the boron carbide content,the Si content decreased and the unreacted B_(4)C amount increased when the sintering temperature reached 1650°C and the sintering time reached 1 h.The unreacted B_(4)C diminished with increasing sintering time and temperature when B_(4)C content was lower than 35wt%.Further microstructure analysis showed a transition area between B_(4)C and Si,with the C content marginally higher than in the Si area.This indicates that after the silicon infiltration,the diffusion mechanism was the primary sintering mechanism of the composites.As the diffusion process progressed,the hardness increased.The maximum values of the Vickers hardness,flexural strength,and fracture toughness of the reaction-bonded B_(4)C–SiC ceramic composite with 12wt%B_(4)C content sintered at 1600°C for 0.5 h were about HV 2400,330 MPa,and 5.2 MPa·m^(0.5),respectively.