BACKGROUND The functional lumen imaging probe(FLIP)is a Food and Drug Administration approved tool to aid the diagnosis and management of esophageal disorders.However,widespread adoption of FLIP remains limited and it...BACKGROUND The functional lumen imaging probe(FLIP)is a Food and Drug Administration approved tool to aid the diagnosis and management of esophageal disorders.However,widespread adoption of FLIP remains limited and its utility in highvolume practices remains unclear.AIM To analyze large sample data on clinical use of FLIP and provide insight on several technical aspects when performing FLIP.METHODS We conducted a retrospective comparative and descriptive analysis of FLIP procedures performed by a single provider at an academic medical center.There was a total of 398 FLIP procedures identified.Patient medical records were reviewed and data regarding demographics and procedural details were collected.Statistical tests,including chi-squared,t-test,and multivariable logistic and linear regression,were performed.RESULTS There was an increase in FLIP cases with each successive time period of 13 months(n=68,146,184,respectively)with notable rises specifically for indications of dysphagia and gastroesophageal reflux disease.There was a shift toward use of the longer FLIP balloon catheter for diagnostic purposes(overall 70.4%vs 29.6%,P<0.01).Many cases(42.8%)were performed in conjunction with other diagnostics/interventions,such as dilation and wireless pH probe placement.Procedures were nearly equally performed with anesthesia vs moderate sedation(51.4%anesthesia),with no major complications.Patients who had anesthesia were less likely to have recurrent antegrade contractions[odds ratio(OR)=0.4,95%CI:0.3-0.8]and were also more likely to have absent contractility(OR=2.4,95%CI:1.3-CONCLUSION FLIP cases have increased in our practice with expanding indications for its use.Given limited normative data,providers should be aware of several potential technical issues,including the possible impact of sedation choice when assessing esophageal motility patterns.展开更多
Investigating gastrointestinal(GI)motility disorders relies on diagnostic tools to assess muscular contractions,peristalsis propagation and the integrity and coordination of various sphincters.Manometries are the gold...Investigating gastrointestinal(GI)motility disorders relies on diagnostic tools to assess muscular contractions,peristalsis propagation and the integrity and coordination of various sphincters.Manometries are the gold standard to study the GI motor function but it is increasingly acknowledged that manometries do not provide a complete picture in relation to sphincters competencies and muscle fibrosis.Endolumenal functional lumen imaging probe(EndoFLIP)an emerging technology,uses impedance planimetry to measure hollow organs cross sectional area,distensibility and compliance.It has been successfully used as a complementary tool in the assessment of the upper and lower oesophageal sphincters,oesophageal body,the pylorus and the anal canal.In this article,we aim to review the uses of EndoFLIP as a tool to investigate GI motility disorders with a special focus on paediatric practice.The majority of EndoFLIP studies were conducted in adult patients but the uptake of the technology in paediatrics is increasing.EndoFLIP can provide a useful complementary data to the existing GI motility investigation in both children and adults.展开更多
The adsorption configurations of molecules adsorbed on substrates can significantly affect their physical and chemical properties. A standing configuration can be difficult to determine by traditional techniques, such...The adsorption configurations of molecules adsorbed on substrates can significantly affect their physical and chemical properties. A standing configuration can be difficult to determine by traditional techniques, such as scanning tunneling microscopy(STM) due to the superposition of electronic states. In this paper, we report the real-space observation of the standing adsorption configuration of phenylacetylene on Cu(111) by non-contact atomic force microscopy(nc-AFM).Deposition of phenylacetylene at 25 K shows featureless bright spots in STM images. Using nc-AFM, the line features representing the C–H and C–C bonds in benzene rings are evident, which implies a standing adsorption configuration. Further density functional theory(DFT) calculations reveal multiple optimized adsorption configurations with phenylacetylene breaking its acetylenic bond and forming C–Cu bond(s) with the underlying copper atoms, and hence stand on the substrate.By comparing the nc-AFM simulations with the experimental observation, we identify the standing adsorption configuration of phenylacetylene on Cu(111). Our work demonstrates an application of combining nc-AFM measurements and DFT calculations to the study of standing molecules on substrates, which enriches our knowledge of the adsorption behaviors of small molecules on solid surfaces at low temperatures.展开更多
A new type of self-assembled molecule ON-OFF fluorescence probe for toxic transition metal ions, made up of thiacalix[4]arene, micelle and fluorescence group, has been studied by DFT/TDDFT method combined with experim...A new type of self-assembled molecule ON-OFF fluorescence probe for toxic transition metal ions, made up of thiacalix[4]arene, micelle and fluorescence group, has been studied by DFT/TDDFT method combined with experiment spectra. Since the mechanism of the optical quenching signal response of such self-assembled micelle probe has always been a controversial issue of uncertainty, the spatial construction and geometric structures of the functional units of probe in the Cu2＋ ion detecting process were calculated and the mechanism was investigated by the molecular transition orbital pairs method to explore the origination of ON-OFF fluorescence sign response. The results presented that the signal response mechanism of the micelle probe is ascribed to F？rster resonance energy transfer（FRET） which provides new sights different from most of the conclusions by the related research work reported.展开更多
In order to obtain creditable data an applicable method to optimize parameters of the Langmuir probes and circuits in a stationary laboratory device is investigated and an experimental criterion of the probe dimension...In order to obtain creditable data an applicable method to optimize parameters of the Langmuir probes and circuits in a stationary laboratory device is investigated and an experimental criterion of the probe dimension is developed. To obtain the electron temperature and density the Electron Energy Distribution Function （EEDF） approach with less computing time and more accurate results is applied, instead of the conventional slope approach. Moreover the influence of the vessel wall materials on the plasma density is discussed briefly, indicating that the dielectric wall is helpful to enhancing the electron density.展开更多
A probe-hole field emission microscope system,controlled by the Apple Ⅱ computer,has been developed and operated successfully for measuring the work function of a single crystalplane.The detection screen,the phototub...A probe-hole field emission microscope system,controlled by the Apple Ⅱ computer,has been developed and operated successfully for measuring the work function of a single crystalplane.The detection screen,the phototube and the amplifier are combined for measuring theprobe-hole current.The combination is calibrated and the calibrated data are used in the com-puter program.The high voltage on the viewing screen is adjusted by using a D/A converter.The total current and the probe-hole current are acquired by using an A/D converter.A programin BASIC is used for processing all data and the Fowler-Nordheim plot parameters are given.Work functions of single crystal planes can then be calculated;as examples,the work functionson the clean W(100)and W(111)planes are measured to be 4.67 eV and 4.45 eV,respectively.展开更多
基金The study was approved by the Stanford University IRB:53329.
文摘BACKGROUND The functional lumen imaging probe(FLIP)is a Food and Drug Administration approved tool to aid the diagnosis and management of esophageal disorders.However,widespread adoption of FLIP remains limited and its utility in highvolume practices remains unclear.AIM To analyze large sample data on clinical use of FLIP and provide insight on several technical aspects when performing FLIP.METHODS We conducted a retrospective comparative and descriptive analysis of FLIP procedures performed by a single provider at an academic medical center.There was a total of 398 FLIP procedures identified.Patient medical records were reviewed and data regarding demographics and procedural details were collected.Statistical tests,including chi-squared,t-test,and multivariable logistic and linear regression,were performed.RESULTS There was an increase in FLIP cases with each successive time period of 13 months(n=68,146,184,respectively)with notable rises specifically for indications of dysphagia and gastroesophageal reflux disease.There was a shift toward use of the longer FLIP balloon catheter for diagnostic purposes(overall 70.4%vs 29.6%,P<0.01).Many cases(42.8%)were performed in conjunction with other diagnostics/interventions,such as dilation and wireless pH probe placement.Procedures were nearly equally performed with anesthesia vs moderate sedation(51.4%anesthesia),with no major complications.Patients who had anesthesia were less likely to have recurrent antegrade contractions[odds ratio(OR)=0.4,95%CI:0.3-0.8]and were also more likely to have absent contractility(OR=2.4,95%CI:1.3-CONCLUSION FLIP cases have increased in our practice with expanding indications for its use.Given limited normative data,providers should be aware of several potential technical issues,including the possible impact of sedation choice when assessing esophageal motility patterns.
文摘Investigating gastrointestinal(GI)motility disorders relies on diagnostic tools to assess muscular contractions,peristalsis propagation and the integrity and coordination of various sphincters.Manometries are the gold standard to study the GI motor function but it is increasingly acknowledged that manometries do not provide a complete picture in relation to sphincters competencies and muscle fibrosis.Endolumenal functional lumen imaging probe(EndoFLIP)an emerging technology,uses impedance planimetry to measure hollow organs cross sectional area,distensibility and compliance.It has been successfully used as a complementary tool in the assessment of the upper and lower oesophageal sphincters,oesophageal body,the pylorus and the anal canal.In this article,we aim to review the uses of EndoFLIP as a tool to investigate GI motility disorders with a special focus on paediatric practice.The majority of EndoFLIP studies were conducted in adult patients but the uptake of the technology in paediatrics is increasing.EndoFLIP can provide a useful complementary data to the existing GI motility investigation in both children and adults.
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2016YFA0202300 and 2018YFA0305800)the National Natural Science Foundation of China(Grant Nos.61888102,61474141,and 21661132006)+2 种基金the Young Scientists Fund of the National Natural Science Foundation of China(Grant No.11604373)the Outstanding Youth Science Foundation,China(Grant No.61622116)the Strategic Priority Research Program of Chinese Academy of Sciences(CAS)(Grant Nos.XDB28000000 and XDB30000000)
文摘The adsorption configurations of molecules adsorbed on substrates can significantly affect their physical and chemical properties. A standing configuration can be difficult to determine by traditional techniques, such as scanning tunneling microscopy(STM) due to the superposition of electronic states. In this paper, we report the real-space observation of the standing adsorption configuration of phenylacetylene on Cu(111) by non-contact atomic force microscopy(nc-AFM).Deposition of phenylacetylene at 25 K shows featureless bright spots in STM images. Using nc-AFM, the line features representing the C–H and C–C bonds in benzene rings are evident, which implies a standing adsorption configuration. Further density functional theory(DFT) calculations reveal multiple optimized adsorption configurations with phenylacetylene breaking its acetylenic bond and forming C–Cu bond(s) with the underlying copper atoms, and hence stand on the substrate.By comparing the nc-AFM simulations with the experimental observation, we identify the standing adsorption configuration of phenylacetylene on Cu(111). Our work demonstrates an application of combining nc-AFM measurements and DFT calculations to the study of standing molecules on substrates, which enriches our knowledge of the adsorption behaviors of small molecules on solid surfaces at low temperatures.
基金supported by the Natural Science Foundation of Liaoning Province(201602516)Shenyang Project of Young and Middle-aged Innovative Talents of Science and Technology(RC170244)
文摘A new type of self-assembled molecule ON-OFF fluorescence probe for toxic transition metal ions, made up of thiacalix[4]arene, micelle and fluorescence group, has been studied by DFT/TDDFT method combined with experiment spectra. Since the mechanism of the optical quenching signal response of such self-assembled micelle probe has always been a controversial issue of uncertainty, the spatial construction and geometric structures of the functional units of probe in the Cu2＋ ion detecting process were calculated and the mechanism was investigated by the molecular transition orbital pairs method to explore the origination of ON-OFF fluorescence sign response. The results presented that the signal response mechanism of the micelle probe is ascribed to F？rster resonance energy transfer（FRET） which provides new sights different from most of the conclusions by the related research work reported.
文摘In order to obtain creditable data an applicable method to optimize parameters of the Langmuir probes and circuits in a stationary laboratory device is investigated and an experimental criterion of the probe dimension is developed. To obtain the electron temperature and density the Electron Energy Distribution Function （EEDF） approach with less computing time and more accurate results is applied, instead of the conventional slope approach. Moreover the influence of the vessel wall materials on the plasma density is discussed briefly, indicating that the dielectric wall is helpful to enhancing the electron density.
基金Subject Supported by the Natural Science Fund of China.
文摘A probe-hole field emission microscope system,controlled by the Apple Ⅱ computer,has been developed and operated successfully for measuring the work function of a single crystalplane.The detection screen,the phototube and the amplifier are combined for measuring theprobe-hole current.The combination is calibrated and the calibrated data are used in the com-puter program.The high voltage on the viewing screen is adjusted by using a D/A converter.The total current and the probe-hole current are acquired by using an A/D converter.A programin BASIC is used for processing all data and the Fowler-Nordheim plot parameters are given.Work functions of single crystal planes can then be calculated;as examples,the work functionson the clean W(100)and W(111)planes are measured to be 4.67 eV and 4.45 eV,respectively.
