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A Sort of Gray-scale Morphological Dilations and Erosions 被引量:2
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作者 GUO Yan-yan GUO Qi 《Chinese Quarterly Journal of Mathematics》 2017年第2期181-186,共6页
We introduce first a sort of gray-scale morphological dilations and erosions, which might have some further applications in image analysis. Then we show that the dilation and the erosion defined here form adjunctive p... We introduce first a sort of gray-scale morphological dilations and erosions, which might have some further applications in image analysis. Then we show that the dilation and the erosion defined here form adjunctive pairs. The duality between the dilation and the erosion and some other properties, such as homothety, of these operators are discussed the Commuting property with translation and as well. 展开更多
关键词 gray-scale dilation gray-scale erosion mathematical morphologyi adjunction duality
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Refractory esophageal stenosis after endoscopic submucosal dissection for esophageal cancer managed with multiple dilations: A case report
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作者 Shu-Hui Yang Hong-Fei Ren +2 位作者 Xia Chen Rui Wang Ming-Guang Zhang 《World Journal of Gastrointestinal Oncology》 2025年第11期303-312,共10页
BACKGROUND Esophageal cancer is a clinically common malignant tumor of the digestive sys-tem.In 2022,it ranked fifth among the leading causes of cancer-related deaths in China.Its predominant symptom is dysphagia,and ... BACKGROUND Esophageal cancer is a clinically common malignant tumor of the digestive sys-tem.In 2022,it ranked fifth among the leading causes of cancer-related deaths in China.Its predominant symptom is dysphagia,and approximately 30%–40%of patients are prone to developing postoperative recurrent stenosis,necessitating repeated esophageal dilation,which significantly affects patients’quality of life.The self-dilation technique,performed by patients,enables preventive esophageal dilation and aims to reduce the frequency of recurrent stenosis.CASE SUMMARY We report the case of a 61-year-old man who underwent repeated esophageal di-lations following endoscopic submucosal dissection.During his eighth hospital admission,a multidisciplinary management team was established to implement an evidence-based self-help balloon dilation technique,facilitate early identifi-cation of nursing concerns and complications,and provide transitional care fo-llowing discharge.The patient reported a high level of satisfaction during the hospital stay.During the 6-month follow-up after discharge,the patient’s quality of life improved,with a substantial reduction in dysphagia.The esophageal stric-ture was successfully dilated from 5 mm to 6 mm,the interval between readmi-ssions was prolonged,and the patient’s weight increased from 49 kg to 50 kg.CONCLUSION The establishment of a multidisciplinary case management team,combined with the implementation of a self-help balloon dilation technique,early identification and management of nursing issues and complications,and person-alized extended care,can significantly enhance patient satisfaction during hospitalization,improve quality of life,and extend the interval between readmissions.These strategies can provide valuable practical guidance for the clinical treatment and nursing of patients with recurrent esophageal stenosis. 展开更多
关键词 Esophageal cancer Esophageal dilation Self-help balloon dilation Endoscopic submucosal dissection Case report
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Different administration regimens of compound tropicamide eyedrops for pupil dilation for children with dark iris:a randomized clinical trial
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作者 Xu Xu Lian-Xin Zhang Jing-Jing Jiang 《International Journal of Ophthalmology(English edition)》 2025年第3期415-419,共5页
AIM:To compare the efficacy of different administration regimens of compound tropicamide eyedrops(CTE)for pupil dilation for children with dark iris.METHODS:A prospective,comparative,randomized interventional study wa... AIM:To compare the efficacy of different administration regimens of compound tropicamide eyedrops(CTE)for pupil dilation for children with dark iris.METHODS:A prospective,comparative,randomized interventional study was conducted.Children in Group 1 received CTE 3 times with a 3min interval between each application.Children in Group 2 received CTE 4 times with a 5min interval between each application.We measured their pupil diameters at baseline(pre-drug instillation)and 30min and 60min post-drug instillation and assessed the pupillary light reflex at 60min post-drug instillation.RESULTS:In total,194 eyes of 101 children were enrolled.The changes of pupil diameter at 30min and 60min post-drug instillation were 1.2±0.6 mm and 2.3±1.0 mm in Group 1,and 2.3±0.9 mm and 3.7±1.0 mm in Group 2,respectively.Group 2 showed a larger change in pupil size than Group 1 at 30min(P<0.01)and 60min(P<0.01).The effect of pupil dilation in Group 2 was 1.25 times that in Group 1.The change in pupil size was positively associated with age.A higher proportion of children in Group 1 had smaller pupil diameter and reactive pupils at the final time point,with only 33 children(33.7%)had final pupil size≥6.5 mm,and only 9 children(9.2%)had non-reactive pupils.Children in Group 2 achieved larger pupil diameter and more nonreactive pupils at the final time point,with 84 children(87.5%)had final pupil size≥6.5 mm,and only 22 children(22.9%)had reactive pupils.CONCLUSION:Increasing the frequency of compound tropicamide and lengthening the interval between eye drop applications can produce stronger mydriatic effects. 展开更多
关键词 pupil dilation MYDRIASIS compound tropicamide dark iris CHILDREN
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Association of circulating Notch1 and VEGF with flow-mediated dilation and aerobic fitness in healthy adults
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作者 Brooke R.Shepley Nick J.Lester +1 位作者 Lana H.Yacoub Anthony R.Bain 《Translational Exercise Biomedicine》 2025年第2期74-82,共9页
Notch1 is a mechanosensitive endothelial receptor that responds to vascular wall shear stress.However,data on Notch1 activity in humans remains limited,particularly regarding its role in endothelial function.Objective... Notch1 is a mechanosensitive endothelial receptor that responds to vascular wall shear stress.However,data on Notch1 activity in humans remains limited,particularly regarding its role in endothelial function.Objectives:Accordingly,the purpose of this study was to determine whether Notch1 is associated with the flow-mediated dilatory(FMD)response and whether it is related to aerobic fitness.A secondary purpose was to determine whether Notch1 is related to concentrations of vascular endothelial growth factor(VEGF).Methods:Sixteen(8M/8F)young(20-30 yrs old)and healthy(BMI:25±4.2 kg/m^(2),blood pressure:117±11.63/69±11.25 mmHg)adults participated in the study.Aerobic fitness was determined by cycle VO_(2) peak.An FMDwas performed on the brachial artery,and blood samples were taken from an antecubital vein at rest(baseline)and 1min after cuff deflation(to align with peak vessel dilation).Concentrations of Notch1 extracellular domain(NECD)and VEGFwere determined from plasma using enzyme-linked immunosorbent assays.Results:In contrast to our hypothesis,concentrations of NECD and VEGF did not change throughout the FMDandwere unrelated to allometrically scaled FMD values(p all>0.05).Likewise,there was no relationship between changes inNECD and VEGF(p=0.331,r=0.127).However,the change in NECD across the FMD was moderately(r=0.515)and significantly(p=0.024)correlated with VO_(2) peak.Conclusions:These novel data indicate that in healthy young adults,Notch1 activity is linked to aerobic fitness but may not be acutely involved in the shear-mediated vasodilatory response. 展开更多
关键词 NOTCH1 vascular function VO_(2)peak vascular endothelial growth factor flow-mediated dilation MECHANOTRANSDUCTION
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Endoscopic retrograde cholangiopancreatography,endoscopic papillary balloon dilation,and laparoscopic hepatectomy for intraand extrahepatic bile duct stones
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作者 Zhi-Liang Chen Hong Fu 《World Journal of Gastrointestinal Surgery》 2025年第1期156-164,共9页
BACKGROUND Intrahepatic and extrahepatic bile duct stones(BDSs)have a high rate of residual stones,a high risk of recurrence,and a high rate of reoperation.It is very important to take timely and effective surgical in... BACKGROUND Intrahepatic and extrahepatic bile duct stones(BDSs)have a high rate of residual stones,a high risk of recurrence,and a high rate of reoperation.It is very important to take timely and effective surgical intervention for patients.AIM To analyze the efficacy,postoperative rehabilitation,and quality of life(QoL)of patients with intra-and extrahepatic BDSs treated with endoscopic retrograde cholangiopancreatography(ERCP)+endoscopic papillary balloon dilation(EPBD)+laparoscopic hepatectomy(LH).METHODS This study selected 114 cases of intra-and extrahepatic BDSs from April 2021 to April 2024,consisting of 55 cases in the control group receiving laparoscopic common bile duct exploration and LH and 59 cases in the observation group treated with ERCP+EPBD+LH.Efficacy,surgical indicators[operation time(OT)and intraoperative blood loss(IBL)],postoperative rehabilitation(time for body temperature to return to normal,time for pain relief,and time for drainage to reduce jaundice),hospital stay,medical expenses,and QoL[Gastrointestinal Quality of Life Index(GIQLI)]were comparatively analyzed.Further,Logistic regression analysis was conducted to analyze factors influencing the QoL of patients with intra-and extrahepatic BDSs.RESULTS The data demonstrated a higher overall effective rate in the observation group compared to the control group(P=0.011),together with notably reduced OT,less IBL,shorter body temperature recovery time,pain relief time,time for drainage to reduce jaundice,and hospital stay(all P<0.05).The postoperative GIQLI of the observation group was more significantly increased compared to the control group(P<0.05).The two groups demonstrated no marked difference in medical expenses(P>0.05).CONCLUSION The above indicates that ERCP+EPBD+LH is effective in treating patients with intra-and extrahepatic BDSs,which is conducive to postoperative rehabilitation and QoL improvement,with promising prospects for clinical promotion. 展开更多
关键词 Intra-and extrahepatic bile duct stones EFFICACY Postoperative rehabilitation Quality of life Endoscopic retrograde cholangiopancreatography Endoscopic papillary balloon dilation
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Failure transition of shear-to-dilation band of rock salt under triaxial stresses 被引量:6
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作者 Jianfeng Liu Xiaosong Qiu +3 位作者 Jianxiong Yang Chao Liang Jingjing Dai Yu Bian 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期56-64,共9页
Great potential of underground gas/energy storage in salt caverns seems to be a promising solution to support renewable energy.In the underground storage method,the operating cycle unfortunately may reach up to daily ... Great potential of underground gas/energy storage in salt caverns seems to be a promising solution to support renewable energy.In the underground storage method,the operating cycle unfortunately may reach up to daily or even hourly,which generates complicated pressures on the salt cavern.Furthermore,the mechanical behavior of rock salt may change and present distinct failure characteristics under different stress states,which affects the performance of salt cavern during the time period of full service.To reproduce a similar loading condition on the cavern surrounding rock mass,the cyclic triaxial loading/unloading tests are performed on the rock salt to explore the mechanical transition behavior and failure characteristics under different confinement.Experimental results show that the rock salt samples pre-sent a diffused shear failure band with significant bulges at certain locations in low confining pressure conditions(e.g.5 MPa,10 MPa and 15 MPa),which is closely related to crystal misorientation and grain boundary sliding.Under the elevated confinement(e.g.20 MPa,30 MPa and 40 MPa),the dilation band dominates the failure mechanism,where the large-size halite crystals are crushed to be smaller size and new pores are developing.The failure transition mechanism revealed in the paper provides additional insight into the mechanical performance of salt caverns influenced by complicated stress states. 展开更多
关键词 Rock salt Cyclic mechanical loading Shear band dilation band Underground gas storage(UGS)
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Effect of endoscopic sphincterotomy and endoscopic papillary balloon dilation endoscopic retrograde cholangiopancreatographies on the sphincter of Oddi 被引量:5
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作者 Kai Fu Ying-Ying Yang +3 位作者 Hui Chen Guang-Xin Zhang Yan Wang Zhi Yin 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1726-1733,共8页
BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP),with its clinical ad-vantages of less trauma and faster recovery,has become the primary treatment for choledocholithiasis.AIM To investigate the effects ... BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP),with its clinical ad-vantages of less trauma and faster recovery,has become the primary treatment for choledocholithiasis.AIM To investigate the effects of different ERCP procedures on the sphincter of Oddi.METHODS The clinical data of 91 patients who underwent ERCP at Yixing Hospital of Traditional Chinese Medicine between February 2018 and February 2021 were analyzed retrospectively.The patients were divided into endoscopic sphinc-terotomy(EST,n=24)and endoscopic papillary balloon dilation(EPBD,n=67)groups.The duration of operation,pancreatic development,pancreatic sphinc-terotomy,intubation difficulties,stone recurrence,and incidence of reflux cho-langitis and cholecystitis were statistically analyzed in patients with a history of choledocholithiasis,pancreatitis,and Oddi sphincter dysfunction in the EST and EPBD groups.RESULTS Differences in hypertension,diabetes,increased bilirubin,small diameter of the common bile duct,or ampullary diverticulum between the two groups were not significant.Statistically significant differences were observed between the two groups concerning sex and age(<60 years).Patients with a history of choledocholithiasis,pancreatitis,and Oddi sphincter dysfunction were higher in the EST group than in the EPBD group.The number of cases of pancreatic development,pancreatic duct sphincterotomy,and difficult intubation were higher in the EST group than in the EPBD group.The number of Oddi’s sphincter manometries,ERCP surgical outcomes,and guidewires entering the pancreatic duct several times in EST group were lower than those in the EPBD group.The numbers of stone recurrences,reflux cholangitis,and cholecystitis were higher in the EST group than in the EPBD group.CONCLUSION In summary,common bile duct stones,pancreatitis history,and multiple guided wire introductions into the pancreatic duct are independent risk factors for EST and EPBD.Based on this evidence,this study can provide actionable insights for clinicians and researchers. 展开更多
关键词 ODDI CHOLANGIOPANCREATOGRAPHY Endoscopic retrograde Risk factors Endoscopic sphincterotomy Endoscopic papillary balloon dilation
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Clinical efficacy of laparoscopic cholecystectomy combined with endoscopic papillary balloon dilation in treatment of gallbladder stones with common bile duct stones: A retrospective study 被引量:1
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作者 Hong-Dan Liu Qi Zhang +1 位作者 Wen-Si Xu Shuang Jin 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1700-1708,共9页
BACKGROUND The incidence of cholelithiasis has been on the rise in recent years,but the choice of procedure is controversial.AIM To investigate the efficacy of laparoscopic cholecystectomy(LC)combined with endoscopic ... BACKGROUND The incidence of cholelithiasis has been on the rise in recent years,but the choice of procedure is controversial.AIM To investigate the efficacy of laparoscopic cholecystectomy(LC)combined with endoscopic papillary balloon dilation(EPBD)in patients with gallbladder stones(GS)with common bile duct stones(CBDS).METHODS The clinical data of 102 patients with GS combined with CBDS were selected for retrospective analysis and divided into either an LC+EPBD group(n=50)or an LC+endoscopic sphincterotomy(EST)group(n=52)according to surgical methods.Surgery-related indexes,postoperative recovery,postoperative complications,and expression levels of inflammatory response indexes were compared between the two groups.RESULTS Total surgical time,stone free rate,rate of conversion to laparotomy,and successful stone extraction rate did not differ significantly between the LC+EPBD group and LC+EST group.Intraoperative hemorrhage,time to ambulation,and length of hospitalization in the LC+EPBD group were lower than those of the LC+EST group(P<0.05).The rate of total complications of the two groups was 9.80%and 17.65%,respectively,and the difference was not statistically significant.No serious complications occurred in either group.At 48 h postoperatively,the expression levels of interleukin-6,tumor necrosis factor-α,high-sensitivity Creactive protein,and procalcitonin were lower in the LC+EPBD group than in the LC+EST group(P<0.05).At 3 d postoperatively,the expression levels of aspartate transaminase,alanine transaminase,and total bilirubin were lower in the LC+EPBD group than in the LC+EST group(P<0.05).CONCLUSION LC combined with EPBD and LC combined with EST are both effective procedures for the treatment of GS with CBDS,in which LC combined with EPBD is beneficial to shorten the patient’s hospitalization time,reduce the magnitude of elevated inflammatory response indexes,and promote postoperative recovery. 展开更多
关键词 Gallbladder stone Common bile duct stone Endoscopic papillary balloon dilation Laparoscopic cholecystectomy Endoscopic sphincterotomy
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Long-term outcomes of urethral balloon dilation for anterior urethral stricture: A prospective cohort study
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作者 Ahmed M.Abdel Gawad Abhijit Patil +3 位作者 Abhishek Singh Arvind P.Ganpule Ravindra B.Sabnis Mahesh R.Desai 《Asian Journal of Urology》 CSCD 2024年第3期480-485,共6页
Objective:To prospectively follow up a cohort of anterior urethral stricture disease patients managed with balloon dilation(BD)for 3 years to evaluate the long-term outcomes and to study factors that contribute to rec... Objective:To prospectively follow up a cohort of anterior urethral stricture disease patients managed with balloon dilation(BD)for 3 years to evaluate the long-term outcomes and to study factors that contribute to recurrence.Methods:This study included men who had urethral BD for significant anterior urethral stricture disease between January 2017 and March 2019.Data about the patient age,stricture characteristics,and recurrence date were recorded,along with information on postoperative indwelling catheter use and operative complications.Furthermore,information about the self-calibration procedure was collected and where available,free flow(FF)measurements during the follow-up period were recorded and analyzed.Success was defined as a lack of symptoms and acceptable FF rates(maximum flow rate>12 mL/s).Results:The final analysis was conducted on 187 patients.The mean follow-up period was 37 months.The long-term overall success rate at the end of our study was 66.8%.Our recurrence rate was 7.4%at 12 months,24.7%at 24 months,and reached 33.2%at the end of our study.The time to recurrence ranged from 91 days to 1635 days,with a mean of 670 days.The stricture-free survival was significantly shorter with lengthy peno-bulbar(p=0.031)and multiple strictures(p=0.015),and in the group of patients who were not committed to self-calibration protocol(p<0.011).However,post-procedural self-calibration was the most important factor that may have decreased the incidence of recurrence(odds ratioZ5.85).Adjuvant self-calibration after BD not only reduced the recurrence rate from 85.4%in the non-self-calibration group to 15.1%in the self-calibration one(p<0.001),but also improved the overall stricture-free survival and FF parameters. 展开更多
关键词 Balloon dilation Internal urethrotomy RECURRENCE SELF-CALIBRATION Urethral stricture
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Dilation,discrimination and Uhlmann's theorem of link products of quantum channels
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作者 雷强 操刘桁 +1 位作者 Asutosh Kumar 武俊德 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期201-206,共6页
We establish the Stinespring dilation theorem of the link product of quantum channels in two different ways,discuss the discrimination of quantum channels,and show that the distinguishability can be improved by self-l... We establish the Stinespring dilation theorem of the link product of quantum channels in two different ways,discuss the discrimination of quantum channels,and show that the distinguishability can be improved by self-linking each quantum channel n times as n grows.We also find that the maximum value of Uhlmann's theorem can be achieved for diagonal channels. 展开更多
关键词 quantum channels link products Stinespring dilation theorem Uhlmann's theorem
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Balloon dilation of congenital perforated duodenal web in newborns: Evaluation of short and long-term results
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作者 Kirill Marakhouski Elena Malyshka +5 位作者 Katsiaryna Nikalayeva Larysa Valiok Aleh Pataleta Kiryl Sanfirau Aliaksandr Svirsky Vasily Averin 《World Journal of Gastrointestinal Endoscopy》 2024年第6期343-349,共7页
BACKGROUND Incomplete congenital duodenal obstruction(ICDO)is caused by a congenitally perforated duodenal web(CPDW).Currently,only six cases of balloon dilatation of the PDW in newborns have been described.AIM To pre... BACKGROUND Incomplete congenital duodenal obstruction(ICDO)is caused by a congenitally perforated duodenal web(CPDW).Currently,only six cases of balloon dilatation of the PDW in newborns have been described.AIM To present our experience of balloon dilatation of a perforated duodenal memb-rane in newborns with ICDO.METHODS Five newborns who underwent balloon dilatation of the CPDW along a prein-stalled guidewire between 2021 and 2023 were included.Nineteen newborns diagnosed with ICDO who underwent laparotomy were included in the control group.RESULTS In all cases,good anatomical and clinical results were obtained.In three cases,a follow-up study was conducted after 1 year.The average time to start enteral feeding per os was significantly earlier in the study group(4.4 d)than in the laparotomic group(21.2 days;P<0.0001).The time spent by patients in the intensive care unit and hospital after balloon dilatation was also significantly shorter.We determined the selection criteria for possible and effective CPDW balloon dilatation in newborns as follows:(1)Presence of dynamic radiographic signs of the passage of a radiopaque substance beyond the zone of narrowing or radiographic signs of pneumatisation of the duodenum and small bowel distal to the web;(2)presence of endoscopic signs of CPDW;(3)successful cannulation with a guidewire performed parallel to the endoscope,with holes in the congenital duodenal web;and(4)successful positioning of the balloon performed along a freestanding guidewire on the web.CONCLUSION Strictly following selection criteria for newborns with ICDO caused by CPDW ensures that endoscopic balloon dilatation using a pre-installed guidewire is safe and effective and shows good 1-year follow-up results. 展开更多
关键词 NEWBORNS Congenital duodenal obstruction Perforated duodenal membrane ENDOSCOPY Balloon dilation
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Time Dilation Cosmology 3: Mathematical Proof of the 3 Temporal and 2 Spatial Acceleration Factors
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作者 Joseph H. (Cass) Forrington 《Journal of Modern Physics》 2024年第12期2228-2237,共10页
This is the fifth paper in a series on Time Dilation Cosmology, TDC. TDC is an eternal holographic model of the universe based on time dilation that ties astrophysics to quantum physics and resolves all the conundrums... This is the fifth paper in a series on Time Dilation Cosmology, TDC. TDC is an eternal holographic model of the universe based on time dilation that ties astrophysics to quantum physics and resolves all the conundrums in astrophysics and serves as a model for the unified field. In the author’s previous four TDC papers, it was demonstrated that all gravitationally induced velocities are compensation for the apparent difference in the rates of time, “dRt”, due to mass/energy densities, and, vice-versa, in all force-induced velocities the dRt is compensation for the velocity, so the uniform evolution of the continuum at c is maintained at the invariant 1 s/s rate of time of the universe as a whole. These compensations make it impossible for an event to lag behind or get ahead of the evolving continuum. When the author did the first velocity formula derivations in “General Relativity: Effects in Time as Causation” [1], the author felt the explanations for the appearance of the 2spatial and the 3temporal acceleration factors in the formulas were correct, but poorly explained and incomplete. This paper is a proof of the temporal and spatial acceleration factors used in the time dilation-based velocity formula derivations in the Time Dilation Cosmology model. 展开更多
关键词 Mathematical Proof Time dilation Cosmology Acceleration Factors
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The Space Dilation: Analyzing Progressive Speed Reduction and Its Relativistic Parallels
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作者 Kreshnik Feka 《Journal of Applied Mathematics and Physics》 2024年第8期2990-3005,共16页
This paper presents a conceptual exploration that draws an intriguing parallelbetween a hypothetical travel scenario and the principles of special relativity. The scenario involves a traveler who reduces their speed b... This paper presents a conceptual exploration that draws an intriguing parallelbetween a hypothetical travel scenario and the principles of special relativity. The scenario involves a traveler who reduces their speed by an amount proportional to the distance traveled. Despite initially traveling at a high speed towards a given destination, the continual reduction in speed results in an asymptotic approach to the goal, analogous to the unattainable speed of light in relativity. Mathematically, the scenario is expressed through the Harmonic Series, demonstrating that the total travel time increases without bound, making the destination theoretically unreachable within a finite timeframe. This exploration mirrors the relativistic velocity addition and time dilation effects, providing a compelling analogy for understanding asymptotic limits. By highlighting the profound implications of diminishing returns and unattainable goals, this paper aims to stimulate further discussion and exploration of these fascinating parallels. 展开更多
关键词 Asymptotic Limits Special Relativity Harmonic Series Time dilation Diminishing Returns
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Time Dilation Cosmology 2
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作者 Joseph H. (Cass) Forrington 《Journal of Modern Physics》 2024年第4期448-461,共14页
This paper is a further elaboration of the author’s Time Dilation Cosmology (TDC) holographic model that ties gravitation and celestial mechanics and kinematics directly to time dilation, resolving all the major conu... This paper is a further elaboration of the author’s Time Dilation Cosmology (TDC) holographic model that ties gravitation and celestial mechanics and kinematics directly to time dilation, resolving all the major conundrums in astrophysics, and ties astrophysics directly to quantum physics. It begins with a brief summary of the TDC model and contains the new derivation for the time dilation version of the formula for summing relativistic velocities, Einstein’s gravitational constant and the time dilation versions for the Lorentz factor and the Euclidean norm of the 3d velocity vector, the two of which can then be used in the Four-velocity formula. It is demonstrated how orbital curvature is manifested as the resultant of two time dilation-manifested velocities. It also explains why an interferometer cannot distinguish free fall from zero gravity and further elaborates on the author’s previous explanations of how spiral galaxies are formed, and contains mathematical proof that Black Holes are actually Magnetospheric Eternally Collapsing Objects (MECOs) that are massless spacetime vortices. 展开更多
关键词 GRAVITATION Time Time dilation Celestial Mechanics ISM: Kinematics and Dynamics Cosmology: Theory Galaxies: Evolution
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Strength and dilatancy of an unsaturated expansive soil at high suction levels
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作者 Ke Chen Xuzhen He +1 位作者 Fayun Liang Daichao Sheng 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第8期5079-5088,共10页
A series of suction-controlled triaxial tests was conducted on Nanyang expansive clay to investigate the effects of dry density and suction on dilatancy and strength.The suction of the soil samples was controlled usin... A series of suction-controlled triaxial tests was conducted on Nanyang expansive clay to investigate the effects of dry density and suction on dilatancy and strength.The suction of the soil samples was controlled using a vapour equilibrium technique,with four suction levels ranging from 3.29 MPa to 198.14 MPa,where water retention is dominated by adsorption.The experimental results show that the tested soil exhibits a brittle failure mode under high suction,significantly distinguishing the hydro-mechanical behaviour of the soil at high suction from that observed at low suction.This brittle failure mode significantly increases the contribution of suction to peak strength compared to residual strength,causes the soil to fail before reaching the critical state,a phenomenon not observed in soils under high suction,and results in dilatancy caused by damage to the soil particle aggregates rather than particle rearrangement.The dilatancy data obtained from the triaxial tests reveal that significant soil dilatancy occurs during shear after reaching peak strength,with the maximum dilatancy angle increasing with suction and decreasing with confining pressure.However,the initial dry density has a negligible impact on the soil's dilatancy under high suction levels.This observation further supports that,for unsaturated soils under high suction levels,dilatancy is attributed to damage to soil particle aggregates rather than the rearrangement of soil particles. 展开更多
关键词 dilatANCY Critical state Shear strength Unsaturated soil
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Magnetic Resonance Imaging Reconstruction Based on Butterfly Dilated Geometric Distillation
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作者 DUO Lin XU Boyu +1 位作者 REN Yong YANG Xin 《Journal of Shanghai Jiaotong university(Science)》 2025年第3期590-599,共10页
In order to improve the reconstruction accuracy of magnetic resonance imaging(MRI),an accurate natural image compressed sensing(CS)reconstruction network is proposed,which combines the advantages of model-based and de... In order to improve the reconstruction accuracy of magnetic resonance imaging(MRI),an accurate natural image compressed sensing(CS)reconstruction network is proposed,which combines the advantages of model-based and deep learning-based CS-MRI methods.In theory,enhancing geometric texture details in linear reconstruction is possible.First,the optimization problem is decomposed into two problems:linear approximation and geometric compensation.Aimed at the problem of image linear approximation,the data consistency module is used to deal with it.Since the processing process will lose texture details,a neural network layer that explicitly combines image and frequency feature representation is proposed,which is named butterfly dilated geometric distillation network.The network introduces the idea of butterfly operation,skillfully integrates the features of image domain and frequency domain,and avoids the loss of texture details when extracting features in a single domain.Finally,a channel feature fusion module is designed by combining channel attention mechanism and dilated convolution.The attention of the channel makes the final output feature map focus on the more important part,thus improving the feature representation ability.The dilated convolution enlarges the receptive field,thereby obtaining more dense image feature data.The experimental results show that the peak signal-to-noise ratio of the network is 5.43 dB,5.24 dB and 3.89 dB higher than that of ISTA-Net+,FISTA and DGDN networks on the brain data set with a Cartesian sampling mask CS ratio of 10%. 展开更多
关键词 butterfly geometric distillation dilation convolution channel attention image reconstruction
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Mitral valve regurgitant area as an independent predictor of in-hospital mortality in elderly patients with dilated car-diomyopathy
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作者 ZHANG Zi-yi LI Xin-yi +5 位作者 WANG Jia-qi GONG Jian-tao TAN Ning TSANG Suk-Ying WONG Wing-tak JIANG Lei 《South China Journal of Cardiology》 2025年第1期42-48,共7页
Background Predicting in-hospital mortality in elderly patients with dilated cardiomyopathy(DCM)is critical for improving clinical management.This study investigated the prognostic significance of mitral valve regurgi... Background Predicting in-hospital mortality in elderly patients with dilated cardiomyopathy(DCM)is critical for improving clinical management.This study investigated the prognostic significance of mitral valve regurgitant area(MVRA)as a predictor of in-hospital mortality.Methods A total of 813 elderly patients(age≥60 years)diag-nosed with DCM were included in this retrospective study,with admissions spanning from January 2010 to Decem-ber 2019.Univariate and multivariate Cox regression analyses were conducted to assess the association between MVRA and in-hospital mortality.Receiver operating characteristic(ROC)curve and Kaplan-Meier survival analy-ses were employed to assess the predictive performance of MVRA and to compare cumulative survival rates be-tween groups,respectively.Results MVRA was significantly associated with in-hospital mortality in both univar-iate and multivariate analyses(HR:1.119,95%CI:1.028-1.218,P=0.009).ROC curve analysis demonstrated good prognostic performance for MVRA[area under curve(AUC):0.714].Kaplan-Meier analysis revealed that patients with high MVRA(HMVRA)had significantly worse in-hospital survival outcomes(log-rank χ2=12.628,P<0.001).Conclusions An increase in MVRA is significantly associated with higher in-hospital mortality in elderly DCM patients,with an MVRA exceeding 7 cm2 indicating a notably increased mortality rate.MVRA serves as a simple and effective parameter for risk assessment and treatment monitoring in DCM patients. 展开更多
关键词 In-hospital mortality dilated cardiomyopathy Elderly patients Mitral regurgitation Risk prediction
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Multi-Head Attention Enhanced Parallel Dilated Convolution and Residual Learning for Network Traffic Anomaly Detection
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作者 Guorong Qi Jian Mao +2 位作者 Kai Huang Zhengxian You Jinliang Lin 《Computers, Materials & Continua》 2025年第2期2159-2176,共18页
Abnormal network traffic, as a frequent security risk, requires a series of techniques to categorize and detect it. Existing network traffic anomaly detection still faces challenges: the inability to fully extract loc... Abnormal network traffic, as a frequent security risk, requires a series of techniques to categorize and detect it. Existing network traffic anomaly detection still faces challenges: the inability to fully extract local and global features, as well as the lack of effective mechanisms to capture complex interactions between features;Additionally, when increasing the receptive field to obtain deeper feature representations, the reliance on increasing network depth leads to a significant increase in computational resource consumption, affecting the efficiency and performance of detection. Based on these issues, firstly, this paper proposes a network traffic anomaly detection model based on parallel dilated convolution and residual learning (Res-PDC). To better explore the interactive relationships between features, the traffic samples are converted into two-dimensional matrix. A module combining parallel dilated convolutions and residual learning (res-pdc) was designed to extract local and global features of traffic at different scales. By utilizing res-pdc modules with different dilation rates, we can effectively capture spatial features at different scales and explore feature dependencies spanning wider regions without increasing computational resources. Secondly, to focus and integrate the information in different feature subspaces, further enhance and extract the interactions among the features, multi-head attention is added to Res-PDC, resulting in the final model: multi-head attention enhanced parallel dilated convolution and residual learning (MHA-Res-PDC) for network traffic anomaly detection. Finally, comparisons with other machine learning and deep learning algorithms are conducted on the NSL-KDD and CIC-IDS-2018 datasets. The experimental results demonstrate that the proposed method in this paper can effectively improve the detection performance. 展开更多
关键词 Network traffic anomaly detection multi-head attention parallel dilated convolution residual learning
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A Case Study of Heart Failure Resulting from Dilated Cardiomyopathy Treated with Sacubitril Valsartan Sodium Tablets in Combination with Qiliqiangxin Capsules
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作者 Qiuwen FU Li XU 《Medicinal Plant》 2025年第3期75-79,共5页
This article presents a case study of a 20-year-old male patient diagnosed with dilated cardiomyopathy(DCM)(NYHA IV).This condition was diagnosed as"heart failure disease"(water overflowing due to yang defic... This article presents a case study of a 20-year-old male patient diagnosed with dilated cardiomyopathy(DCM)(NYHA IV).This condition was diagnosed as"heart failure disease"(water overflowing due to yang deficiency,intermingled phlegm and stasis)in traditional Chinese medicine(TCM).The treatment approach employed a combination of TCM and Western medicine.Western medicine involved the administration of sacubitril valsartan sodium tablets to inhibit ventricular remodeling,in conjunction with diuretics and cardiotonic agents.Initially,TCM utilized a static infusion of Shenfu injection,which was subsequently supplemented with Qiliqiangxin capsules to invigorate qi,warm yang,activate blood circulation,and promote diuresis.After a follow-up period of 3 years,the patient's ejection fraction(EF)improved from 23%to 51%,and the left ventricular end diastolic diameter(LVed)decreased from 68 to 52 mm,accompanied by a significant alleviation of symptoms.These findings indicate that the combined treatment of TCM and Western medicine can synergistically enhance cardiac function and impede the progression of the disease,thereby offering valuable insights for the optimal management of DCM. 展开更多
关键词 dilatED cardiomyopathy (DCM) Heart failure Sacubitril VALSARTAN SODIUM TABLETS Qiliqiangxin capsules Chest TIGHTNESS Shortness of BREATH
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Bicuspid Aortic Valve Disease,the Dilated Proximal Aorta,and the Surgical Treatment Options:A Narrative Review
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作者 Wilhelm Mistiaen 《Congenital Heart Disease》 2025年第3期305-323,共19页
The presence of a bicuspid aortic valve(BAV)is the most common congenital heart anomaly,which can remain asymptomatic for decades,if it is not a part of a syndrome,such as Turner syndrome or genetic connective tissue ... The presence of a bicuspid aortic valve(BAV)is the most common congenital heart anomaly,which can remain asymptomatic for decades,if it is not a part of a syndrome,such as Turner syndrome or genetic connective tissue disorders.There are several classifications for BAV,each with its advantages and drawbacks.The condition can lead to valvular malfunction such as regurgitation and stenosis,but is often associated with dilatation of the aortic root,the ascending aorta,the aortic arch,or a combination.Altered flow patterns due to the valve dysfunction as well as the breakdown of elastin in the aortic wall could be responsible for this development.Published surgical series are usually small and research designs vary,which makes the formulation of universal recommendations for treatment difficult.This narrative review provides data from the most recent series in this respect.Often,the condition becomes symptomatic in patients who are about 10 years younger compared to those with a diseased tricuspid aortic valve.The timing of surgery of the valve depends on the degree of its dysfunction.Repair of a dysfunctional BAV should be attempted whenever possible because of the patient’s age.The options for valve repair are summarized,including the need for the use as the effective geometric height.The use of a pericardial patch and the presence of calcified areas of the valve can be predictors for an increased need for reintervention.In those cases,a valve replacement should be preferred.If a dilatation of the ascending aorta or the aortic root is present,this should also be addressed surgically,but the threshold for such a procedure varies.Several techniques are available to treat a dilated ascending aorta and root.For the latter,remodeling and reimplantation can be applied.Depending on the patient’s characteristics,the size of the dilatation,and the affected part,the most appropriate technique should be selected.This requires surgical expertise,which can only be obtained in high-volume centers. 展开更多
关键词 Bicuspid aortic valve aortic valve repair aortic root aneurysm ascending aorta dilatation
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