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
Background: Many factors can contribute to atherosclerotic-type vascular changes in older individuals or men. Thus, confining the investigation to young women with no clinical evidence of the condition could enhance u...Background: Many factors can contribute to atherosclerotic-type vascular changes in older individuals or men. Thus, confining the investigation to young women with no clinical evidence of the condition could enhance understanding of the early stages of cardiovascular disease. The aim of this study was to determine whether carotid mean/max intima-media thickness (IMT) and brachial flow-mediated dilation (FMD) values, which are well-known event-related indices, are associated with laboratory data and the other vascular indices of atherosclerosis in healthy young women. Methods: Carotid mean/max IMT and brachial FMD were measured in young women with no clinical evidence of atherosclerosis (n = 110;mean age, 39 years) who were instructed not to eat, drink or smoke after 9 PM the evening before testing. All participants also underwent laboratory assessment, including simultaneous measurements of arterial stiffness such as augmentation index (AI), cardioankle vascular index (CAVI) and brachial-ankle pulse wave velocity (baPWV). Results: Mean IMT was signifi-cantly and positively associated with age (p = 0.002), CAVI (p = 0.044), low-density lipoprotein-cholesterol (LDL-C, p = 0.047) and high-sensitive C-reactive protein (hs-CRP, p = 0.002) values but was not related to FMD, AI, baPWV or triglycerides (TG) in the multivariate regression analysis. Similarly, max IMT was positively associated with age (p p = 0.003) and hs-CRP (p = 0.005) values but was not related to FMD, AI, CAVI, baPWV, TG or blood pressure level in the multivariate regression analysis. The association between LDL-C and max IMT was much stronger than that between LDL-C and mean IMT. Brachial FMD was positively associated only with heart rate in the multivariate regression analysis. Conclusions: These results suggest that mean IMT more closely represents the sclerotic aspect of vascular change, whereas max IMT represents the atherotic aspect in healthy young women. Although the relationship between the autonomic nervous system and heart rate is well-known, there may be a complex interaction between the autonomic nervous system and endothelial function.展开更多
The validity of the flow-mediated dilation (FMD) test has been doubted due to the lack of normalization to the primary stimulus, shear stress. Shear stress can be calculated using a simplified mathematical model based...The validity of the flow-mediated dilation (FMD) test has been doubted due to the lack of normalization to the primary stimulus, shear stress. Shear stress can be calculated using a simplified mathematical model based on Poiseuille’s law. Poiseuille’s law assumes that the blood velocity profile is parabolic. The presence of turbulence will violate this assumption. The Reynolds number (RE) is used to define critical values for the transition from laminar to turbulent flow. Between RE values of 2000 and 4000, flow enters a transitional phase where turbulence is possible. Purpose: To determine whether brachial artery blood flow becomes turbulent during reactive hyperemia following forearm ischemia. Methods: Eleven healthy male subjects (25 ± 5 years) were tested. Brachial artery diameters and blood velocities were measured continuously following 2, 4, 6 and 10 minutes ischemia. The peak post-ischemic RE (REpeak) and RE integrated over 40 seconds (RE40) post-ischemia were calculated. Results: There was a significant change in REpeak (F4,7 = 98.573, p = ≤ 0.001) and RE40) (F4,7) = 50.613, p = ≤ 0.001) in response to ischemia. Within-subjects contrasts revealed a significant increase in REpeak and RE40 for each duration of ischemia versus baseline (p = ≤ 0.001). Following 4 minutes of ischemia there was approximately 12 seconds of potentially turbulent flow. Conclusion: Blood flow transitions between laminar and turbulent flow during ischemia-induced reactive hyperemia. This may limit the efficacy of estimating shear stress when using the standard FMD test protocol.展开更多
Background Carotid artery intima-media thickness （CIMT） and brachial artery flow-mediated dilation percentage （FMD%） are common parameters used for detecting subclinical atherosclerosis. This study compared subcli...Background Carotid artery intima-media thickness （CIMT） and brachial artery flow-mediated dilation percentage （FMD%） are common parameters used for detecting subclinical atherosclerosis. This study compared subclinical atherosclerosis of the carotid and brachial arteries in rheumatoid arthritis （RA） patients and healthy controls using high resolution ultrasonography. We also investigated their correlation with clinical factors and the association between FMD% and CIMT.展开更多
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
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
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
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
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
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
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
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
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
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
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
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
Nicotinamide adenine dinucleotide (NADH/NAD+) is involved in important biochemical reactions in human metabolism, including participation in energy production by mitochondria. The changes in fluorescence intensity as ...Nicotinamide adenine dinucleotide (NADH/NAD+) is involved in important biochemical reactions in human metabolism, including participation in energy production by mitochondria. The changes in fluorescence intensity as a function of time in response to blocking and releasing of blood flow in a forearm are used as a measure of oxygen transport with blood to the tissue, which directly correlates with the skin microcirculation status. In this paper, a non-invasive dynamic monitoring system based on blood flow-mediated skin fluorescence (FMSF) technology is developed to monitor the NADH fluorescence intensity of skin tissue during the process of blocking reactive hyperemia. Simultaneously, laser speckle contrast imaging (LSCI) and laser Doppler flowmetry (LDF) were used to observe blood flow, blood oxygen saturation (SOt2) and relative amount of hemoglobin (rHb) during the measurement process, which helped to explore NADH dynamics relevant physiological changes. A variety of parameters have been derived to describe NADH fluorescence curve based on the FMSF device. The experimental results are conducive to understanding the NADH measurement and the physiological processes related to it, which help FMSF to be a great avenue for in vivo physiological, clinical and pharmacological research on mitochondrial metabolism.展开更多
AIMTo investigate whether consumption of an energy drink will acutely impair endothelial function in young healthy adults.METHODSEnergy drinks are being consumed more and more worldwide, and have been associated with ...AIMTo investigate whether consumption of an energy drink will acutely impair endothelial function in young healthy adults.METHODSEnergy drinks are being consumed more and more worldwide, and have been associated with some deaths in adolescents and young adults, especially when consumed while exercising. After fasting and not smoking for at least 8 h prior, eleven medical students (9 males) received an electrocardiogram, blood pressure and pulse check, and underwent baseline testing (BL) of endothelial function using the technique of endothelium-dependent flow mediated dilatation (FMD) with high-resolution ultrasound (according to recommended guidelines of the University of Wisconsin Atherosclerosis Imaging Research Program Core Laboratory). The subjects then drank an energy beverage (EB), a 24-oz can of Monster Energy, and the above was repeated at 90 min after consumption. The relative FMD (%) was calculated as the ratio between the average post-cuff release and the baseline diameter. Each image was checked for quality control, and each artery diameter was measured from the media to media points by two experts, 3 measurements at the QRS complex, repeated on 3 separate beats, and then all were averaged.RESULTSSubjects characteristics averages (given with standard deviations) include: Age 24.5 ± 1.5 years, sex 9 male and 2 female, weight 71.0 ± 9.1 kg, height 176.4 ± 6.0 cm, BMI 22.8 ± 2.7 kg/m<sup>2</sup>. The hemodynamics were as follows, BL vs EB group respectively (mean ± SD): Heart rate 65.2 ± 11.3 vs 68.2 ± 11.8 beats per minute, systolic blood pressure 114.0 ± 10.4 mmHg vs 114.1 ± 10.4 mmHg, diastolic blood pressure 68.8 ± 9.3 mmHg vs 70.6 ± 7.1 mmHg; all were not significantly different. However after drinking the EB, a significantly attenuated peak FMD response was measured (mean ± SD): BL group 5.9% ± 4.6% vs EB group 1.9% ± 2.1%; P = 0.03). Given the increased consumption of energy beverages associated with exercise in young adults, more research is needed.CONCLUSIONEnergy beverage consumption has a negative impact on arterial endothelial function in young healthy adults.展开更多
Objectives: To evaluate the association of diastolic function of the left ventricle with flowme-diated dilatation (FMD) in uncomplicated Type 2 diabetes mellitus patients. Methods: Eighty-two uncomplicated Type 2 diab...Objectives: To evaluate the association of diastolic function of the left ventricle with flowme-diated dilatation (FMD) in uncomplicated Type 2 diabetes mellitus patients. Methods: Eighty-two uncomplicated Type 2 diabetic patients were examined by pulse and tissue Doppler echocardiography and FMD of brachial artery. The patients were divided into 2 groups according to the size of the left ventricular relaxation parameter—E’. Results: The average age of the patients was 61 ± 6 years. FMD was 5.0 ± 1.8% in 41 patients with E’ from 3 to 7.4 cm/s (mean 6 cm/s) comparing to 5.1 ± 1.9% (p = 0.96) in 41 patients with E’ from 7.5 to 10.9 cm/s (mean 8.9 cm/s). E/E’ was 11.2 ± 2.3 in the group with lower E’ and 9.1 ± 1.6 in the group with higher E’ (p 0.001). Linear negative correlation was found between E/E’ and FMD for the patients with E’ from 3 to 7.4 cm/s (R2 = 0.131;p = 0.025) but not for the group of patients with the higher E’. The significant association between FMD and E/E’ was confirmed by multivariate analysis ((Rc)2 = 0.233;p 0.05). Conclusion: FMD has no impact on the left ventricular relaxation. However FMD is negatively associated with E/E’ in Type 2 diabetic patients who have low E’ as a sign of an impaired early relaxation.展开更多
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
基金supported by the Natural Sciences and Engineering Research Council of Canada(NSERC)Discovery Grant,held by Dr.Bain(RGPIN-2020-05760).
文摘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.
文摘Background: Many factors can contribute to atherosclerotic-type vascular changes in older individuals or men. Thus, confining the investigation to young women with no clinical evidence of the condition could enhance understanding of the early stages of cardiovascular disease. The aim of this study was to determine whether carotid mean/max intima-media thickness (IMT) and brachial flow-mediated dilation (FMD) values, which are well-known event-related indices, are associated with laboratory data and the other vascular indices of atherosclerosis in healthy young women. Methods: Carotid mean/max IMT and brachial FMD were measured in young women with no clinical evidence of atherosclerosis (n = 110;mean age, 39 years) who were instructed not to eat, drink or smoke after 9 PM the evening before testing. All participants also underwent laboratory assessment, including simultaneous measurements of arterial stiffness such as augmentation index (AI), cardioankle vascular index (CAVI) and brachial-ankle pulse wave velocity (baPWV). Results: Mean IMT was signifi-cantly and positively associated with age (p = 0.002), CAVI (p = 0.044), low-density lipoprotein-cholesterol (LDL-C, p = 0.047) and high-sensitive C-reactive protein (hs-CRP, p = 0.002) values but was not related to FMD, AI, baPWV or triglycerides (TG) in the multivariate regression analysis. Similarly, max IMT was positively associated with age (p p = 0.003) and hs-CRP (p = 0.005) values but was not related to FMD, AI, CAVI, baPWV, TG or blood pressure level in the multivariate regression analysis. The association between LDL-C and max IMT was much stronger than that between LDL-C and mean IMT. Brachial FMD was positively associated only with heart rate in the multivariate regression analysis. Conclusions: These results suggest that mean IMT more closely represents the sclerotic aspect of vascular change, whereas max IMT represents the atherotic aspect in healthy young women. Although the relationship between the autonomic nervous system and heart rate is well-known, there may be a complex interaction between the autonomic nervous system and endothelial function.
文摘The validity of the flow-mediated dilation (FMD) test has been doubted due to the lack of normalization to the primary stimulus, shear stress. Shear stress can be calculated using a simplified mathematical model based on Poiseuille’s law. Poiseuille’s law assumes that the blood velocity profile is parabolic. The presence of turbulence will violate this assumption. The Reynolds number (RE) is used to define critical values for the transition from laminar to turbulent flow. Between RE values of 2000 and 4000, flow enters a transitional phase where turbulence is possible. Purpose: To determine whether brachial artery blood flow becomes turbulent during reactive hyperemia following forearm ischemia. Methods: Eleven healthy male subjects (25 ± 5 years) were tested. Brachial artery diameters and blood velocities were measured continuously following 2, 4, 6 and 10 minutes ischemia. The peak post-ischemic RE (REpeak) and RE integrated over 40 seconds (RE40) post-ischemia were calculated. Results: There was a significant change in REpeak (F4,7 = 98.573, p = ≤ 0.001) and RE40) (F4,7) = 50.613, p = ≤ 0.001) in response to ischemia. Within-subjects contrasts revealed a significant increase in REpeak and RE40 for each duration of ischemia versus baseline (p = ≤ 0.001). Following 4 minutes of ischemia there was approximately 12 seconds of potentially turbulent flow. Conclusion: Blood flow transitions between laminar and turbulent flow during ischemia-induced reactive hyperemia. This may limit the efficacy of estimating shear stress when using the standard FMD test protocol.
文摘Background Carotid artery intima-media thickness （CIMT） and brachial artery flow-mediated dilation percentage （FMD%） are common parameters used for detecting subclinical atherosclerosis. This study compared subclinical atherosclerosis of the carotid and brachial arteries in rheumatoid arthritis （RA） patients and healthy controls using high resolution ultrasonography. We also investigated their correlation with clinical factors and the association between FMD% and CIMT.
文摘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.
基金Supported by the National Natural Science Foundation of China(No.82371093,No.72342015)R&D Program of Beijing Municipal Education Commission(No.KZ202110025039).
文摘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.
文摘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.
基金This research was financially supported by the Science and Technology Department of Sichuan Province Project,China(Grant Nos.2022YFSY0007,2021YFH0010)the National Scientific Science Foundation of China(Grant No.U20A20266).
文摘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.
文摘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.
基金Supported by Qiqihar Science and Technology Plan Joint Guidance Project,No.LHYD-2021058.
文摘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.
文摘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.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61877054,12031004,and 12271474).
文摘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.
基金The study was reviewed and approved by the Research Ethics Committee of Republican Scientific and Practical Center of Pediatric Surgery Minsk,Republic of Belarus(Protocol 9 of August 24,2023).
文摘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.
文摘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.
文摘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.
文摘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.
文摘Nicotinamide adenine dinucleotide (NADH/NAD+) is involved in important biochemical reactions in human metabolism, including participation in energy production by mitochondria. The changes in fluorescence intensity as a function of time in response to blocking and releasing of blood flow in a forearm are used as a measure of oxygen transport with blood to the tissue, which directly correlates with the skin microcirculation status. In this paper, a non-invasive dynamic monitoring system based on blood flow-mediated skin fluorescence (FMSF) technology is developed to monitor the NADH fluorescence intensity of skin tissue during the process of blocking reactive hyperemia. Simultaneously, laser speckle contrast imaging (LSCI) and laser Doppler flowmetry (LDF) were used to observe blood flow, blood oxygen saturation (SOt2) and relative amount of hemoglobin (rHb) during the measurement process, which helped to explore NADH dynamics relevant physiological changes. A variety of parameters have been derived to describe NADH fluorescence curve based on the FMSF device. The experimental results are conducive to understanding the NADH measurement and the physiological processes related to it, which help FMSF to be a great avenue for in vivo physiological, clinical and pharmacological research on mitochondrial metabolism.
基金Supported by McGovern Medical School,The University of Texas Health Science Center at Houston,7000 Fannin St#1200,Houston,TX 77030,University of Texas,No.130744
文摘AIMTo investigate whether consumption of an energy drink will acutely impair endothelial function in young healthy adults.METHODSEnergy drinks are being consumed more and more worldwide, and have been associated with some deaths in adolescents and young adults, especially when consumed while exercising. After fasting and not smoking for at least 8 h prior, eleven medical students (9 males) received an electrocardiogram, blood pressure and pulse check, and underwent baseline testing (BL) of endothelial function using the technique of endothelium-dependent flow mediated dilatation (FMD) with high-resolution ultrasound (according to recommended guidelines of the University of Wisconsin Atherosclerosis Imaging Research Program Core Laboratory). The subjects then drank an energy beverage (EB), a 24-oz can of Monster Energy, and the above was repeated at 90 min after consumption. The relative FMD (%) was calculated as the ratio between the average post-cuff release and the baseline diameter. Each image was checked for quality control, and each artery diameter was measured from the media to media points by two experts, 3 measurements at the QRS complex, repeated on 3 separate beats, and then all were averaged.RESULTSSubjects characteristics averages (given with standard deviations) include: Age 24.5 ± 1.5 years, sex 9 male and 2 female, weight 71.0 ± 9.1 kg, height 176.4 ± 6.0 cm, BMI 22.8 ± 2.7 kg/m<sup>2</sup>. The hemodynamics were as follows, BL vs EB group respectively (mean ± SD): Heart rate 65.2 ± 11.3 vs 68.2 ± 11.8 beats per minute, systolic blood pressure 114.0 ± 10.4 mmHg vs 114.1 ± 10.4 mmHg, diastolic blood pressure 68.8 ± 9.3 mmHg vs 70.6 ± 7.1 mmHg; all were not significantly different. However after drinking the EB, a significantly attenuated peak FMD response was measured (mean ± SD): BL group 5.9% ± 4.6% vs EB group 1.9% ± 2.1%; P = 0.03). Given the increased consumption of energy beverages associated with exercise in young adults, more research is needed.CONCLUSIONEnergy beverage consumption has a negative impact on arterial endothelial function in young healthy adults.
文摘Objectives: To evaluate the association of diastolic function of the left ventricle with flowme-diated dilatation (FMD) in uncomplicated Type 2 diabetes mellitus patients. Methods: Eighty-two uncomplicated Type 2 diabetic patients were examined by pulse and tissue Doppler echocardiography and FMD of brachial artery. The patients were divided into 2 groups according to the size of the left ventricular relaxation parameter—E’. Results: The average age of the patients was 61 ± 6 years. FMD was 5.0 ± 1.8% in 41 patients with E’ from 3 to 7.4 cm/s (mean 6 cm/s) comparing to 5.1 ± 1.9% (p = 0.96) in 41 patients with E’ from 7.5 to 10.9 cm/s (mean 8.9 cm/s). E/E’ was 11.2 ± 2.3 in the group with lower E’ and 9.1 ± 1.6 in the group with higher E’ (p 0.001). Linear negative correlation was found between E/E’ and FMD for the patients with E’ from 3 to 7.4 cm/s (R2 = 0.131;p = 0.025) but not for the group of patients with the higher E’. The significant association between FMD and E/E’ was confirmed by multivariate analysis ((Rc)2 = 0.233;p 0.05). Conclusion: FMD has no impact on the left ventricular relaxation. However FMD is negatively associated with E/E’ in Type 2 diabetic patients who have low E’ as a sign of an impaired early relaxation.
基金support from the China Scholarship Council(CSC)-University of Technology Sydney joint scholarship and the National Key R&D Program of China(Grant No.2016YFC0800200)is gratefully acknowledged.
文摘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.
