Wave Velocity Research Articles

Haemodynamics of hyperthyroidism: increased cardiac work and findings related to vasodilatation.

Hyperthyroidism increases cardiovascular morbidity and mortality, but the underlying mechanisms are not fully understood. In this study we compared non-invasive haemodynamics between 20 hyperthyroid patients and 60 euthyroid subjects. The measurements were performed median 6 days after the initiation of antithyroid medication when the patients were still hyperthyroid. Three controls matched for age, sex, body mass index, and smoking status were selected for each patient. Recordings were performed during rest and passive head-up tilt using whole-body impedance cardiography, radial pulse wave analysis, and finger blood pressure measurements. Systolic and diastolic blood pressures in the aorta and radial artery were similar in hyperthyroid and euthyroid subjects, while finger blood pressure was 16/12 mmHg lower in hyperthyroidism (p<0.001). Pulse wave velocity and aortic pulse pressure were similar, but radial pulse pressure was ~5 mmHg higher in hyperthyroidism (p=0.040) due to augmented amplification (p=0.045). Systemic vascular resistance was reduced (-18%), whereas heart rate (+19 beats/min), cardiac index (+28%), and left cardiac work (+31%) were increased in hyperthyroidism (p<0.001). Subendocardial viability ratio, reflecting the balance between coronary perfusion and pressure load, was reduced by 19% in hyperthyroidism (p<0.001). Compared with euthyroid subjects, hyperthyroid patients presented with reductions in systolic and diastolic finger blood pressures (p<0.001), and higher increase in heart rate (p=0.014) during upright posture. Hyperthyroid patients exhibited hyperdynamic circulation, reduced vascular resistance, reduced peripheral but not central blood pressure, and higher pulse pressure amplification. Furthermore, left cardiac workload was increased in parallel with unfavourable changes in coronary perfusion conditions.

Quantitative Analysis on Vessel Stiffness and Vector Flow Imaging in the Assessment of Carotid Artery Structural and Functional Changes in Patients With Type 2 Diabetes

ObjectiveTo explore the value of RF-data-based quantitative analysis on vessel stiffness (R-QVS) combined with dynamic vector flow imaging (VFI) in evaluating structural and functional changes in the carotid arteries of patients with type 2 diabetes mellitus (T2DM). MethodsA prospective study was conducted between October 2022 and April 2024, including 275 consecutive subjects (50 volunteers as controls, 108 patients with T2DM and normal carotid intima-media thickness (CIMT), and 117 patients with T2DM and thickened CIMT). Carotid intima-media thickness (IMT) was measured using real-time intima-media thickness (RIMT) technology, while R-QVS was employed to measure the systolic diameter (Diam), displacement (Dist), hardness coefficient (HC), and pulse wave velocity (PWV) of the distal segment of the carotid artery. VFI was used to measure the maximum wall shear stress (WSSmax), mean wall shear stress (WSSmean), and maximum instantaneous velocity (Vmax) of the vessel wall. Differences in ultrasound parameters among the three groups were compared, and receiver operating characteristic (ROC) curves were plotted to calculate the area under the curve (AUC), evaluating the efficacy of these parameters in assessing structural and functional changes in the carotid arteries of patients with T2DM. ResultsThere were statistically significant differences in carotid IMT, Diam, Dist, HC, PWV, WSSmax, and Vmax among the three groups (all p < 0.01). The AUCs for evaluating structural and functional changes in the carotid arteries of patients with T2DM using carotid ultrasound parameters Diam, Dist, HC, PWV, WSSmax, and Vmax were 0.64, 0.68, 0.83, 0.88, 0.86, and 0.82, respectively. Multiple linear regression analysis identified Dist., HC, PWV, WSSmax, and WSSmean as influencing factors for CIMT in T2DM patients (with β values of -0.406, 0.515, 0.564, -0.472, and -0.438, respectively; all p < 0.05). ConclusionR-QVS and VFI techniques contribute to the early assessment of structural and functional changes in the carotid arteries of patients with type 2 diabetes mellitus. Compared with controls, T2DM patients exhibit more advanced functional changes than morphological changes despite normal CIMT. The enhanced sensitivity, reproducibility, and detailed assessment capabilities of these methods make them valuable tools in the early detection and intervention of cardiovascular risk in T2DM.

Lower estimates of myocardial perfusion are associated with greater aortic perivascular adipose tissue density in humans independent of aortic stiffness.

Aortic perivascular adipose tissue (aPVAT) density is associated with age-related aortic stiffness in humans and therefore, may contribute to cardiovascular dysfunction. A lower subendocardial viability ratio (SEVR), an estimate of myocardial perfusion, indicates greater cardiovascular disease (CVD) risk and is associated with aortic stiffness in clinical populations. However, the influence of aortic stiffness on the relation between aPVAT density and SEVR/cardiovascular (CV) hemodynamics in apparently healthy adults is unknown. We hypothesize that greater aPVAT density will be associated with lower SEVR and higher CV hemodynamics independent of aortic stiffness. Fourteen (6 males/8 females; mean age, 55.4 ± 5.6 yr; body mass index, 25.5 ± 0.6 kg/m2) adults completed resting measures of myocardial perfusion (SEVR), CV hemodynamics (pulse wave analysis), aortic stiffness [carotid-femoral pulse wave velocity (cfPWV)], and a computed tomography scan to acquire aPVAT and visceral adipose tissue (VAT) density. Greater aPVAT density (i.e., higher density) was associated with lower SEVR (r = -0.78, P < 0.001) and a higher systolic pressure time integral (r = 0.49, P = 0.03), forward pulse height (r = 0.49, P = 0.03), reflected pulse height (r = 0.55, P = 0.02), ejection duration (r = 0.56, P = 0.02), and augmentation pressure (r = 0.69, P = 0.003), but not with the diastolic pressure time integral (r = -0.22, P = 0.22). VAT density was not associated with SEVR or any CV hemodynamic endpoints (all, P > 0.05). Furthermore, the relation between aPVAT density and SEVR remained after adjusting for aortic stiffness (r = -0.66, P = 0.01) but not age (r = -0.24, P > 0.05). These data provide initial evidence for aPVAT as a novel yet understudied local fat depot contributing to lower myocardial perfusion in apparently healthy adults with aging.NEW & NOTEWORTHY Aortic perivascular adipose tissue (aPVAT) density is associated with aging and aortic stiffness in humans and, therefore, may contribute to lower myocardial perfusion. We demonstrate that greater aPVAT, but not visceral adipose tissue density is associated with lower myocardial perfusion and augmentation pressure independent of aortic stiffness, but not independent of age. These data provide novel evidence for aPVAT as a potential therapeutic target to improve myocardial perfusion and cardiovascular function in humans with aging.

Relationship Between Renin, Aldosterone, Aldosterone-to-Renin Ratio and Arterial Stiffness and Left Ventricular Mass Index in Young Adults.

Primary aldosteronism, characterized by renin-independent aldosterone production, is associated with adverse cardiovascular remodeling and outcomes. Elevated cardiovascular risk is observed even in subclinical forms of primary aldosteronism according to studies conducted primarily in middle-aged and elderly populations. This study aimed to assess whether early changes in primary aldosteronism biomarkers during young adulthood are associated with arterial stiffness and left ventricular mass index (LVMI) before the onset of overt disease. The Raine Study is a longitudinal, population-based cohort study in Western Australia that enrolled women during pregnancy. We analyzed the data from the offspring of these women at 17 (2006-2009) and 27 (2016-2018) years of age. Participants with elevated high-sensitivity C-reactive protein (>10 mg/L) and female participants who were on oral contraception were excluded. Pulse wave velocity and aortic augmentation index were measured by SphygmoCor Pulse Wave System at both ages, and aortic distensibility and LVMI were measured by cardiac magnetic resonance imaging at 27 years. Multivariable linear regression was used to examine the relationship between plasma renin, aldosterone, or aldosterone-to-renin ratio and arterial stiffness and LVMI. Mediation analysis was used to test the role of systolic blood pressure. This study included 859 participants at 17 (38.0% female) and 758 participants at 27 (33.2% female) years of age. Females had lower renin concentration at both 17 (20.7 mU/L versus 25.7 mU/L; P<0.001) and 27 (12.0 mU/L versus 15.4 mU/L; P<0.001) years of age; hence, the aldosterone-to-renin ratio was significantly higher at both 17 (18.2 versus 13.5; P<0.001) and 27 (21.0 versus 15.6; P<0.001) years of age in females compared with males. At 27 years of age, a significant association was detected between aldosterone and LVMI in males (β=0.009 [95% CI, 0.001-0.017]; P=0.027) and between aldosterone-to-renin ratio and LVMI in females (β=0.098 [95% CI, 0.001-0.196]; P=0.050) independently of systolic blood pressure and other confounders. No association was found between primary aldosteronism biomarkers and measures of arterial stiffness (pulse wave velocity, aortic augmentation index, and aortic distensibility) at either age. Aldosterone concentration and aldosterone-to-renin ratio were positively associated with the LVMI in young males and females, respectively, independently of systolic blood pressure. Long-term follow-up is required to determine whether the relationship persists over time, and clinical trials are needed to assess the cardiovascular benefits of early interventions to block aldosterone.

The impact of uninterrupted sitting on central and peripheral cardiovascular function in pre-menopausal and post-menopausal women.

Independently, both prolonged uninterrupted sitting and the onset of menopause negatively impact markers of cardiovascular risk. Whether their combination augment these responses additively remains unknown. This study assessed whether prolonged uninterrupted sitting causes greater central and peripheral cardiovascular dysfunction in post-menopausal women compared to pre-menopausal women. To address this, 23 healthy women (13 pre-menopausal [43.77 ± 4.30years] and 10 post-menopausal [57.20 ± 8.55years]) sat uninterrupted for 2-h. Carotid-femoral pulse wave velocity (cf-PWV), pulse wave analysis (PWA), lower limb venous pooling (HHb), and calf circumference were assessed pre-and post-sitting using general linear mixed models, with age as a covariate. Changes in MAP over time (both between and within groups) was assessed using a two-way repeated-measures-ANOVA. There were no significant interactions for any outcome measures. However, for cf-PWV, there was a significant main effect of group (Δ = 0.854 ± 0.354m s-1; p = 0.026, ηp2 = 0.707). For PWA, only heart rate (HR) and pressure forwards (Pf) showed significant main effects 13 of time [Δ = 6 ± 1 bts-min-1, p < 0.001, ηp2 = 0.861] and group [Δ = 3.893 ± 1.450mmHg, p = 0.016, ηp2 = 0.271], respectively. Both HHb (Δ = 2.737 ± 0.952, p = 0.009, ηp2 = 0.742) and calf circumference (Δ = 0.812 ± 0.128cm, p < 0.001, ηp2 = 0.863) significantly increased over time. Whilst post-menopausal women demonstrated greater overall arterial stiffness (increased cf-PWV at baseline), there was no difference in cardiovascular response (central or peripheral) to 2-h of prolonged sitting between the pre- and post-menopausal women.

The association of ideal cardiovascular health and its change with subclinical atherosclerosis according to glucose status: A prospective cohort study.

An updated definition was developed to better evaluate cardiovascular health (CVH). We aimed to investigate whether optimal or improvement of six CVH metrics defined by new Life's Essential 8 (LE8) may counteract the risk of subclinical atherosclerosis among patients with hyperglycemia. We conducted a prospective analysis of 5225 participants without prior cardiovascular diseases, of whom 4768 had complete data on CVH change. Subjects with CVH scores of 0-49, 50-79, and 80-100 points were categorized as having low, moderate, or high CVH, respectively. Subclinical atherosclerosis was evaluated by brachial-ankle pulse wave velocity, pulse pressure and albuminuria, both separately and in combination. Of the 5225 participants, 1937 (37.1%) had normal glucose regulation, while 3288 (62.9%) had hyperglycemia. The multivariable-adjusted odds ratio (OR) for composite subclinical atherosclerosis was 2.34 (95% confidence interval [CI], 1.88-2.91), 1.43 (95% CI, 1.21-1.70), and 0.74 (95% CI, 0.46-1.18), for participants with hyperglycemia who had low, moderate, or high overall CVH scores, respectively, compared with participants with normal glucose regulation. In addition, compared with those with stable CVH and normal glucose regulation, participants who exhibited greater improvements in overall CVH from 2010 to 2014 had a reduced risk of composite subclinical atherosclerosis with an OR of 0.72 (95% CI, 0.53-0.98) for those with normal glucose regulation, and 1.13 (95% CI, 0.87-1.48) for those with hyperglycemia. The novel defined CVH using six metrics was inversely associated with subsequent risk of subclinical atherosclerosis. Both the status of CVH and its changes modified the relationship between hyperglycemia and subclinical atherosclerosis.

Arterial function is preserved in successfully treated patients with psoriasis vulgaris.

Endothelial dysfunction is an early precursor of atherosclerosis and is common in patients with psoriasis, presumably primarily due to psoriasis-related inflammation. We investigated endothelial function, arterial stiffness, and circulating markers of endothelial activation in young patients with psoriasis vulgaris of varying severity, all of whom were effectively treated achieving PASI 90. We conducted a cross-sectional study of 80 patients (54 men/26 women, 30-45 years) who were effectively treated with topical therapy, methotrexate, adalimumab, secukinumab or guselkumab, and 20 healthy controls. Endothelial dysfunction was measured by flow-mediated dilation and arterial stiffness was measured by pulse wave velocity and common carotid artery stiffness. The following circulating biomarkers of endothelial activation were measured: ICAM-1, VCAM-1, E- and P-selectin, GDF-15, and TRAIL. Endothelial function and arterial stiffness parameters did not differ between patients with effectively treated psoriasis and the control group. Circulating endothelial activation biomarkers did not show relevant differences between the groups of effectively treated patients or controls. Although cardiovascular disease is the leading cause of morbidity and mortality in patients with psoriasis, effective antipsoriatic treatment appears to slow the progression of atherosclerosis, even when there are cardiovascular risk factors, such as smoking or obesity. This may suggest that antipsoriatic treatment exerts a cardioprotective effect. Our results suggest that early and effective treatment of varying-severity psoriasis vulgaris in young patients appears to prevent arterial dysfunction related to psoriasis and consequent cardiovascular risk.The study is registered at http://clinicaltrials.gov (identifier: NCT05957120).

Impact of three-month treatment with pitavastatin on arterial stiffness in patients with hypercholesterolemia: a prospective observational study

BackgroundAlthough several studies have highlighted the benefits of statins in improving arterial stiffness, there is limited research on whether pitavastatin, a more recently developed statin, has similar effects. This study aimed to investigate the impact of pitavastatin on arterial stiffness in patients with hypercholesterolemia. MethodsThis prospective study enrolled 115 patients with hypercholesterolemia (mean age 59 years; 22% female) who had not previously been treated with statins. Participants underwent lifestyle interventions followed by administration of pitavastatin (2 or 4 mg daily) if target low-density lipoprotein (LDL) cholesterol levels were not achieved. The primary outcome measured was the change in brachial-ankle pulse wave velocity (baPWV) from baseline after three months of treatment. ResultsPitavastatin treatment significantly reduced LDL cholesterol by 41.1% (from 158 ± 28 to 93.0 ± 29.6 mg/dL; P < 0.001). Additionally, systolic blood pressure (SBP) decreased significantly from 130 ± 14 mmHg to 126 ± 14 mmHg (P < 0.001), representing a 2.9% reduction, and baPWV decreased significantly from 1,522 ± 325 to 1,407 ± 289 cm/s (P < 0.001), a 7.6% reduction. There was a significant correlation between changes in SBP and changes in baPWV (r = 0.565; P < 0.001). Even after adjusting for changes in SBP, the reduction in baPWV induced by pitavastatin remained statistically significant (P < 0.001). ConclusionsA three-month treatment with pitavastatin effectively reduced arterial stiffness in patients with hypercholesterolemia, alongside significant improvements in lipid profiles and blood pressure reductions. These findings support the use of pitavastatin for managing key cardiovascular risk factors.

Comprehensive influence of dimensionless wave velocity and expansion ratio on energy absorption characteristics of variable wavelength traveling wave turbine

Based on the traveling wave motion of fish, this paper introduces a new type of variable wavelength traveling wave turbine that significantly differs from traditional turbine designs in its mechanical structure. By developing a two-dimensional traveling wavy plate model and conducting numerical simulations, this study investigates the relationship between the dimensionless wave velocity, variable wavelength coefficient, and expansion ratio, as well as their combined effects on the energy absorption characteristics of the variable wavelength traveling wave turbine. The results reveal that energy absorption efficiency peaks at an optimal dimensionless wave velocity, which is unaffected by changes in the variable wavelength coefficient. Furthermore, the expansion ratio significantly influences both the dimensionless wave velocity and the variable wavelength coefficient, with an optimal ratio of π∗ = 2.5 achieving 90.42 % efficiency. The energy absorption characteristics of the plate with a larger variable wavelength coefficient are found to be constrained by the expansion ratio. Additional analysis reveals that flow characteristics, such as the pressure distribution, vortex street, and velocity field surrounding the traveling wavy plate, are closely related to its energy absorption performance. These findings provide valuable insights for the design of variable wavelength traveling wave turbine.

Association between leisure-time physical activity and arterial stiffness in adults of the ELSA-Brasil study: a mediation analysis.

We aimed at defining the direct and the mediated pathways for the association between leisure-time physical activity (LTPA) and carotid-to-femoral pulse wave velocity (cf-PWV), and also to identify whether these effects are influenced by sex and age. Cross-sectional data from 13 718 adults (35-74 years) were obtained at the baseline of the ELSA-Brasil study. The cf-PWV was obtained by measuring the pulse transit time and the distance traveled by the pulse between the carotid and the femoral, as well as clinical and anthropometric parameters were measured. The levels of LTPA were determined by applying the long form of the International Physical Activity Questionnaire (IPAQ). Classical cardiovascular risk factors were independently associated with cf-PWV. Path analysis showed that increased levels of LTPA were directly associated with lower cf-PWV in both men and women ( β : -0.123 ± 0.03 vs. 0.065 ± 0.029, P for sex = 0.165), except for diabetes. Also, the mediated effect of LTPA on SBP and DBPs, heart rate, BMI, and fasting glucose, was associated with lower cf-PWV in men and women ( β : -0.113 ± 0.016 vs. -0.104 ± 0.016, P for sex = 0.692), except for diabetes. When age was tested as a moderator, the direct effect did not change significantly according to participants' age, regardless of sex. However, the mediated effect increases in both men and women over 50 years. Our findings support that LTPA in adults reduces cf-PWV by acting in different ways according to age. Physical activity in older individuals improves cardiometabolic risk factors and thus mitigates the stiffening of large arteries.

PAI-1 Regulates the Cytoskeleton and Intrinsic Stiffness of Vascular Smooth Muscle Cells.

Plasma concentration of PAI-1 (plasminogen activator inhibitor-1) correlates with arterial stiffness. Vascular smooth muscle cells (SMCs) express PAI-1, and the intrinsic stiffness of SMCs is a major determinant of total arterial stiffness. We hypothesized that PAI-1 promotes SMC stiffness by regulating the cytoskeleton and that pharmacological inhibition of PAI-1 decreases SMC and aortic stiffness. PAI-039, a specific inhibitor of PAI-1, and small interfering RNA were used to inhibit PAI-1 expression in cultured human SMCs. Effects of PAI-1 inhibition on SMC stiffness, F-actin (filamentous actin) content, and cytoskeleton-modulating enzymes were assessed. WT (wild-type) and PAI-1-deficient murine SMCs were used to determine PAI-039 specificity. RNA sequencing was performed to determine the effects of PAI-039 on SMC gene expression. In vivo effects of PAI-039 were assessed by aortic pulse wave velocity. PAI-039 significantly reduced intrinsic stiffness of human SMCs, which was accompanied by a significant decrease in cytoplasmic F-actin content. PAI-1 gene knockdown also decreased cytoplasmic F-actin. PAI-1 inhibition significantly increased the activity of cofilin, an F-actin depolymerase, in WT murine SMCs, but not in PAI-1-deficient SMCs. RNA-sequencing analysis suggested that PAI-039 upregulates AMPK (AMP-activated protein kinase) signaling in SMCs, which was confirmed by Western blotting. Inhibition of AMPK prevented activation of cofilin by PAI-039. In mice, PAI-039 significantly decreased aortic stiffness and tunica media F-actin content without altering the elastin or collagen content. PAI-039 decreases intrinsic SMC stiffness and cytoplasmic stress fiber content. These effects are mediated by AMPK-dependent activation of cofilin. PAI-039 also decreases aortic stiffness in vivo. These findings suggest that PAI-1 is an important regulator of the SMC cytoskeleton and that pharmacological inhibition of PAI-1 has the potential to prevent and treat cardiovascular diseases involving arterial stiffening.

Seismic response of deep soft soil sites with varying shear wave velocities

The variations in seismic response between deep soft soil sites with different shear wave velocities were not fully understood. This study focuses on the seismic response of deep soft soil sites in the lower reaches of the Yangtze River, China. A nonlinear dynamic finite element model was developed for two representative deep soft soil sites with borehole profiles and the shear wave velocity tested by the single borehole method. Two nonlinear cyclic constitutive models are used and thus compared through the site seismic response. To accurately calibrate the nonlinear cyclic model parameters, resonant column tests were conducted on 21 soil samples collected from the two boreholes. The results show that the peak ground acceleration (PGA) under low-frequency (Liuan) input motion was higher for soft soil sites compared to that under medium- and high-frequency (Kobe and Nahanni) input motions. The PGA amplification factor for deep soft soil sites under different input motions can be approximated by an exponential function. The peak ground acceleration tends to be lower as the equivalent shear wave velocity (Vse) decreases. The shapes of the spectral acceleration were similar for the two sites, despite a substantial difference in the Vse between them. Additionally, a crossover point was observed in the spectral acceleration for the two sites. The period corresponding to this crossover point increased with increasing intensity of input motions, indicating that the sites became softer with higher intensity and thus generally exhibited a longer characteristic period of the spectral acceleration. This paper also highlights the significance of selecting nonlinear constitutive models and the precise calibration of model parameters in the seismic response analysis of deep soft soil sites, providing a scientific basis for future similar site analyses.

Relationship of Dickkopf-1 With Atherosclerosis and Arterial Stiffness in Renal Transplant Recipients

IntroductionDickkopf wingless (Wnt) signaling pathway inhibitor-1 (DKK-1) is a potent antagonist of the WNT canonical signaling pathway. DKK-1 is a substance that exerts anabolic effects on bone and is also involved in vascular cell regulation. The study aimed to determine the relationship of DKK-1 with atherosclerosis as determined by carotid artery intima-media thickness (CA-IMT) and arterial stiffness (AS) as determined by brachial-ankle pulse wave velocity (baPWV) in renal transplant recipients (RTRs). MethodsA total of 62 (62%) male and 38 (438%) female RTRs with a mean age of 44.22 ± 10.88 years were included in the study. RTRs were compared with 65 healthy individuals. CA-IMT measurement with ultrasonography was used as a marker of atherosclerosis. The presence of AS was detected with the baPWV device. ResultsCreatinine, CA-IMT, and baPWV were higher in the RTRs compared to the healthy subjects. No difference was determined between the two groups regarding log10 DKK-1. No difference was noted in the levels of CA-IMT and baPWV in patients with log10 DKK-1 > 3.83 pg/mL compared to patients with ≤3.83 pg/mL. Correlation and multivariate analyses showed no correlation between log10 DKK-1 and CA-IMT and baPWV. DiscussionIn RTRs, an increased development of atherosclerosis and AS was observed compared to healthy individuals. There was no difference in DKK-1 between the groups based on improved renal function. DKK-1 was not correlated with atherosclerosis and AS.

Elevated Pulse Wave Velocity In Highly Sedentary Endometrial Cancer Survivors: A Call For Future Interventions

Elevated Pulse Wave Velocity In Highly Sedentary Endometrial Cancer Survivors: A Call For Future Interventions

Phenotypic Characterisation of Obstructive Sleep Apnoea in Acute Coronary Syndrome

Recent neutral randomised clinical trials have created clinical equipoise for treating obstructive sleep apnoea (OSA) for managing cardiovascular risk. The importance of defining the links between OSA and cardiovascular disease is needed with the aim of advancing the robustness of future clinical trials. We aimed to define the clinical correlates and characterise surrogate cardiovascular markers in patients with acute coronary syndrome (ACS) and OSA. Overall, 66 patients diagnosed with ACS were studied. Patients underwent an unattended polysomnogram after hospital discharge (median [interquartile range] 62 [37-132] days). The Epworth Sleepiness Scale, Berlin, and STOP-BANG questionnaires were administered. Surrogate measures of vascular structure and function, and cardiovascular autonomic function were conducted. Pulse wave amplitude drop was derived from the pulse oximetry signals of the overnight polysomnogram. OSA (apnoea-hypopnea index [AHI] ≥5) was diagnosed in 94% of patients. Moderate-to-severe OSA (AHI≥15) was observed in 68% of patients. Daytime sleepiness (Epworth Sleepiness Scale ≥10) was reported in 17% of patients. OSA screening questionnaires were inadequate to identify moderate-to-severe OSA, with an area under the receiver operating characteristic curve of approximately 0.64. Arterial stiffness (carotid-femoral pulse wave velocity, 6.1 [5.2-6.8] vs 7.4 [6.6-8.6] m/s, p=0.002) and carotid intima-media thickness (0.8 [0.7-1.0] vs 0.9 [0.8-1.0] mm, p=0.027) was elevated in patients with moderate-to-severe OSA. After adjusting for age, sex and body mass index, these relationships were not statistically significant. No relationships were observed in other surrogate cardiovascular markers. A high prevalence of OSA in a mostly non-sleepy population with ACS was identified, highlighting a gross underdiagnosis of OSA among cardiovascular patients. The limitations of OSA screening questionnaires highlight the need for new models of OSA screening as part of cardiovascular risk management. A range of inconsistent abnormalities were observed in measures of vascular structure and function, and these appear to be largely explained by confounding factors. Further research is required to elucidate biomarkers for the presence and impact of OSA in ACS patients.

Two-dimensional boundary layer receptivity to finite periodic disturbances

Receptivity is the focus and frontier of the research on boundary layer transition and flow drag reduction, but the temporal and spatial evolution of Tollmien–Schlichting waves (T-S waves) is not yet fully investigated, limiting the development of highly efficient laminar flow control techniques. In the present study, the local receptivity problem of the laminar boundary layer on a zero-pressure-gradient flat plate is investigated by using the direct numerical simulation, considering both the temporal and spatial evolution characteristics of the T-S waves. External disturbances at fixed frequencies are introduced in the form of velocity pulsations with different periods to excite T-S waves. The temporal and spatial evolution characteristics of the T-S waves excited by different forms and periods of disturbances are studied. It is found that the amplitude, frequency, and wave velocity of the T-S wave induced by the external multi-period disturbances are different from those induced by the constant disturbances. These conclusions are the same as those of T-S wave induced by wall inhalation. After a further investigation on this particular phenomenon, the influence mechanism of external disturbances on the receptivity process is revealed. This new research finding enriches the instability theory and provides a reference for more efficient applications on active laminar flow control technologies.

Signal detection

Acoustic emission (AE) occurring in concrete fracture process is a combination of concrete fracture at local material level and the propagation of induced elastic waves at structural level. Simulation of the fracture-induced AE in concrete needs a model that is able to address the fracture behavior and the wave propagation at the same time. However, to date, no available modelling tools can simulate the whole fracture-induced AE process. Among others, the lattice models have the potential to achieve the simulation of the whole fracture-induced AE process. However, the lattice models are currently restricted to statistical analysis of AE events in fracture process. This paper investigates the feasibility and limitation of lattice model for the simulation of elastic wave propagation process. Several simulation cases are performed considering the propagation of both plane waves and point-source waves. The simulation results, in terms of wave velocity and geometric spreading loss of wave amplitudes, agree well with the analytical solutions. This study represents the first step for the simulation of complete fracture-induced AE waves in concrete.

The association between arterial stiffness and socioeconomic status: a cross-sectional study using estimated pulse wave velocity

BackgroundThe impact of socioeconomic status (SES) on arterial stiffness remains unclear. This study aimed to explore the association between both personal and household income, as well as education level, and estimated pulse wave velocity (ePWV).MethodsA total of 13,539 participants (mean age 52.9 ± 16.7 years; 57.1% women) from the Korean National Health and Nutrition Survey database were analyzed. For SES variables, information on personal and household income and education level was collected using standardized questionnaires.ResultsThe ePWV did not show significant differences across groups categorized by individual income levels (P = 0.183). However, there was a noticeable trend of decreasing ePWV with increasing household income levels (P < 0.001). Additionally, ePWV demonstrated a significant negative correlation with higher education levels, indicating that ePWV decreased in groups with higher educational attainment (P < 0.001). In multiple linear regression analyses, both household income (β = -0.055; P < 0.001) and education level (β = -0.076; P < 0.001) were negatively associated with ePWV, even after adjusting for potential confounders.ConclusionsLower household income and lower education levels were associated with higher ePWV, providing further evidence of the influence of SES on arterial stiffness.Graphical abstract

The importance of arterial stiffness in pediatric patients with type 1 diabetes mellitus: What's new?

Youths with type 1 diabetes (T1D) exhibits higher levels of pulse wave velocity (PWV) compared to healthy controls. Higher PWV in T1D subjects is associated with increased hazard of progression in albuminuria, decline in eGFR, cardiovascular (CV) events and mortality. In the recently published work by Georeli et al., increased PWV was associated with poor glycemic control as expressed by time-in-range (TIR) < 50 % in T1D children, adolescents and young adults. This finding is of great interest, since it is well known that glycemic control, as measured by TIR, is an important contributor of CV risk. The duration of TIR < 50 % is not reported by the authors, but is of importance, knowing that CGM provide data for the last 3–6 months, depending on the CGM model. In conclusion, PWV looks promising for risk stratification in T1D, but its exact role in T1D still remains to be fully explored.

Nonlinear soliton spiral induces coupled multimode dynamics in multi-stable dissipative metamaterials

With the robust and self-trapped properties, recent advances about soliton dynamics in multi-stable mechanical metamaterials have led to many innovative techniques from signal processing to robotics. This work proposes a multi-stable mechanical metamaterial driven by nonlinear dissipative solitons, in which the coupling and decoupling of multiple locomotion modes can be achieved. Based on a cylinder network with asymmetric energy landscape, the uniform field model of Landau theory is developed. During the theoretical calculation, the analytical solutions of several dissipative solitons are derived, which allow multiple special behaviors of solitary waves, such as wave velocity gaps, directional propagation and spiral phase transition. By incorporating such effects into robotic designs, a variety of complex movements can be achieved by a single structure, including hopping, rolling, rotating, swinging, bending and translational components. In particular, as excitation positions change, the mechanical metamaterial can flexibly switch multiple locomotion modes without changing configurations, e.g., spinning and spin-less, straight and oblique as well as coupled multimode movements. This work wishes to provide some new inspirations for the applications of nonlinear elastic wave metamaterials and phase transition theory in robotics.