Pulse Wave Research Articles

Mass-selective instability and resonance ejection modes for DIT with rectangular asymmetric wave shape.

We consider the operation of a digital linear ion trap with resonance radial ejection and mass selective instability modes. Periodic wave shape has a positive part with amplitude and duration and negative part with amplitude and duration , where T is the period. The mapping of the stability diagram, calculations of the well's depth and ion oscillations spectra are presented. The process of resonant excitation of ion oscillations by a dipole sinusoidal signal is studied, as well as ion ejection at the stability boundary. The trajectory method is used for this purpose. It is shown that the mass selectivity of dipole excitation is twice as large for rectangular wave shape compared to sinusoidal wave shape. Increasing the diameter of the round rods of the linear trap gives an increase in the resolving power. The possibility of DIT operation in mass-selective instability mode at the boundary point is discussed.

Examining the challenges of blood pressure estimation via photoplethysmogram

The use of observed wearable sensor data (e.g., photoplethysmograms [PPG]) to infer health measures (e.g., glucose level or blood pressure) is a very active area of research. Such technology can have a significant impact on health screening, chronic disease management and remote monitoring. A common approach is to collect sensor data and corresponding labels from a clinical grade device (e.g., blood pressure cuff) and train deep learning models to map one to the other. Although well intentioned, this approach often ignores a principled analysis of whether the input sensor data have enough information to predict the desired metric. We analyze the task of predicting blood pressure from PPG pulse wave analysis. Our review of the prior work reveals that many papers fall prey to data leakage and unrealistic constraints on the task and preprocessing steps. We propose a set of tools to help determine if the input signal in question (e.g., PPG) is indeed a good predictor of the desired label (e.g., blood pressure). Using our proposed tools, we found that blood pressure prediction using PPG has a high multi-valued mapping factor of 33.2% and low mutual information of 9.8%. In comparison, heart rate prediction using PPG, a well-established task, has a very low multi-valued mapping factor of 0.75% and high mutual information of 87.7%. We argue that these results provide a more realistic representation of the current progress toward the goal of wearable blood pressure measurement via PPG pulse wave analysis. For code, see our project page: https://github.com/lirus7/PPG-BP-Analysis

Multi-scale fusion and efficient feature extraction for enhanced sonar image object detection

Sonar imaging is an underwater detection technology that relies on the transmission and reception of acoustic pulse waves. This technique plays a crucial role in various domains including underwater archaeology, energy exploration, and oceanographic surveying. A primary challenge in sonar imaging is the low signal-to-noise ratio and significant noise interference, issues that are influenced by the constraints of equipment performance and the underwater environment. Traditional object detection techniques have been inadequate in effectively extracting deep features from sonar images possessing targets with complex structures and have also demonstrated shortcomings in the fusion processing of target features at multiple scales, thereby affecting the robustness and accuracy of object detection. To improve the performance of sonar image object detection, we propose an advanced detection framework that integrates efficient feature extraction with multi-scale feature fusion. We employ EfficientNet as the backbone network. EfficientNet exhibits excellent feature extraction capabilities through comprehensive adjustments of depth, width, and resolution. We introduce a dual-channel attention module that blends Squeeze-and-Excitation (SE) and Efficient Channel Attention (ECA) mechanisms to amplify the expression of crucial feature channels and suppress the lesser ones. Additionally, we utilize a modified bidirectional feature pyramid network (BiFPN) to strengthen the integration of features across different layers. Employing these methods, we amalgamate the features into a shared weights classification network and bounding box prediction network for accurate target class discernment and localization. The experimental outcomes provide evidence of the notable superlative nature of the proposed framework in sonar image object detection, effectively ameliorating detection performance amidst noise interference.

Cardiorespiratory Fitness Benefits of High-Intensity Interval Training After Stroke: A Randomized Controlled Trial.

Limited evidence supports the effects of short-interval high-intensity interval training (HIIT) for improving cardiorespiratory fitness (V̇O2peak) after stroke. We aimed to compare the effects of 12 weeks of short-interval HIIT versus moderate-intensity continuous training (MICT) on V̇O2peak, cardiovascular risk factors, and mobility outcomes among individuals ≥6 months poststroke. This study was a multi-site, 12-week randomized controlled trial (NCT03614585) with an 8-week follow-up. Participants were randomized into 3 d/wk of HIIT (10×1 minute 80%-100% heart rate reserve interspersed with 1 minute 30% heart rate reserve [19 minutes]) or MICT (20-30 minutes 40%-60% heart rate reserve). Secondary outcomes of the trial, including V̇O2peak, cardiovascular risk factors (carotid-femoral pulse wave velocity, blood pressure, and waist-hip ratio), and mobility (6-minute walk test, 10 m gait speed), were reported. Linear mixed model analyses with a group×study time point interaction evaluated between-group differences. Of the 305 potential participants, 82 consented (mean [SD] age 64.9 [9.3] years, 32 females [39%], 1.8 [1.2] years poststroke) and were randomized to HIIT (n=42, mean [SD] baseline V̇O2peak 17.3 [5.9] mL/kg·min) or MICT (n=40, mean [SD] baseline V̇O2peak 17.2 [6.0] mL/kg·min). Participants attended 82% of visits (n=2417/2952). No adverse events occurred during the study period. A significant group×study time point interaction was found (χ2=8.46; P=0.015) for V̇O2peak at 12 weeks (mean difference, 1.81 [95% CI, 0.58-3.04]; P=0.004) whereby the HIIT group had greater gains in V̇O2peak (∆3.52 mL/kg·min [95% CI, 2.47-4.57]; P<0.001) compared with the MICT group (∆1.71 mL/kg·min [95% CI, 0.55-2.86]; P=0.001). There was no between-group difference in V̇O2peak (mean difference, 1.08 [95% CI, -0.26 to 2.42]; P=0.11) at 8-week follow-up. No group×study time point interactions were found for cardiovascular risk factors or mobility outcomes. Short-interval HIIT may be an effective alternative to MICT for improving V̇O2peak at 12 weeks postintervention. URL: https://clinicaltrials.gov; Unique identifier: NCT03614585.

Association between vascular aging and cognitive function in Chinese adults

BackgroundVascular health has been associated with cognition but related evidence is limited in Chinese. The objective of this study was to examine the association of vascular aging assessed by arterial stiffness and blood pressure with cognitive function in an unselected Chinese population.MethodsIn the Tianning Cohort (N = 5158), indicators of arterial stiffness and blood pressure including carotid-femoral pulse wave velocity (cfPWV), ankle-brachial index (ABI), pulse pressure (PP), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were measured. Cognitive function was assessed using the Mini Mental State Examination (MMSE) questionnaire. We applied Poisson regression and logistic regression to examine the associations of vascular aging and blood pressure with cognitive function.Results76 (1.47%) participants had impaired cognitive function diagnosed by a MMSE score of less than 24 points. Participants with a higher level of PP were more likely to have a decreased score of MMSE (β=-0.0121, P < 0.001 for log-transformed pulse pressure) and a higher risk of having impaired cognitive function (OR = 5.95, 95%CI: 2.02–17.79, P < 0.001 for log-transformed PP). Per standard deviation increment in SBP was significantly associated with lower MMSE score (β=-0.0020, P < 0.001) and impaired cognitive function (OR = 1.69, 95%CI: 1.38–2.06, P < 0.001). No significant associations were found regarding other parameters.ConclusionsBlood pressure and hypertension were associated with cognitive function in Chinese adults. PP may be a potential predictor for impaired cognitive function.

Discrepancies between general and central obesity in arterial stiffness: observational studies and Mendelian randomization study

BackgroundObesity has been linked to arterial stiffness, while no consensus was reached on the association. We aimed to clarify the association of general and central obesity with arterial stiffness by combining observational studies and Mendelian randomization (MR) study.MethodsTwo cross-sectional studies were performed in UK Biobank and Fuqing Cohort, respectively. Two-sample MR study was conducted using summary data of GWASs from GIANT consortium and UK Biobank. General obesity and central obesity were measured using body mass index (BMI) and waist circumference (WC), respectively. Arterial stiffness was measured by arterial stiffness index (ASI) in UK Biobank or branchial-ankle pulse wave velocity (baPWV) in Fuqing Cohort.ResultsTwo observational studies found a consistent positive association of BMI and WC with arterial stiffness when adjusting for age, sex, education, smoking, alcohol drinking, physical activity, and LDL cholesterol. However, when additionally adjusting for metabolic traits (i.e., systolic blood pressure, diastolic blood pressure, blood glucose, triglycerides, high-density lipoprotein cholesterol, and WC or BMI), the association with BMI changed to be inverse. As compared to the lowest quintile group, the adjusted ORs across groups of second to fifth quintile were 0.93, 0.90, 0.83, and 0.72 in UK Biobank and 0.88, 0.65, 0.63, and 0.50 in Fuqing Cohort. In contrast, the positive relationship with WC remained stable with the adjusted ORs of 1.23, 1.46, 1.60, and 1.56 in UK Biobank and 1.35, 1.44, 1.77, and 1.64 in Fuqing Cohort. MR analyses provided supportive evidence of the negative association with BMI (OR = 0.97, 95%CI = 0.94–1.00) and the positive association with WC (OR = 1.14, 95%CI = 1.08–1.20).ConclusionsObservational and genetic analyses provide concordant results that central obesity is independently related to arterial stiffness, while the role of general obesity depends on metabolic status.

Gonadal status modulates large elastic artery stiffness in healthy middle-aged and older men.

Hypogonadism is a risk factor for cardiovascular disease (CVD) in men related, in part, to increased oxidative stress. Elevated large artery stiffness and central pulsatile hemodynamics (e.g., pulse pressure and wave reflection magnitude) are independent risk factors for CVD. However, whether large artery stiffness and central pulsatile hemodynamics are (1) elevated in hypogonadal men independent of traditional CVD risk factors and (2) related to increased oxidative stress is unknown. Young men (N = 23; 30 ± 4years) and middle-aged/older (MA/O) men with normal (> 400-1000ng/dL; n = 57; 59 ± 7years) or low testosterone (< 300ng/dL; n = 21; 59 ± 7years) underwent assessments of large artery stiffness (carotid ß-stiffness via ultrasonography) and central pulsatile hemodynamics (pulse wave analysis; SphygmoCor XCEL) following an infusion of saline or vitamin C to test the tonic suppression of vascular function by oxidative stress. Carotid stiffness differed by age (p < 0.001) and gonadal status within MA/O men (low testosterone vs. normal testosterone: 9.3 ± 0.7 vs. 8.0 ± 0.3U, p = 0.036). Central pulsatile hemodynamics did not differ by age or gonadal status (p > 0.119). Vitamin C did not alter carotid stiffness in any group (p > 0.171). There was a significant group × infusion interaction on aortic reflection magnitude (p = 0.015). Vitamin C treatment reduced aortic reflection magnitude in young and MA/O men with normal testosterone (both p < 0.001) but not MA/O men with low testosterone (p = 0.891). Collectively, hypogonadism may accelerate age-related large artery stiffening in MA/O men with low testosterone, independent of CVD risk factors; however, this is not related to increased reactive oxygen species sensitive to an acute vitamin C infusion.

Association between exposure to air pollution and arterial stiffness in participants with and without atherosclerotic cardiovascular disease.

To assess the association of air pollution exposure at different time scales with arterial stiffness in participants with and without atherosclerotic cardiovascular disease (ASCVD). We measured participants' arterial stiffness with brachial-ankle pulse wave velocity (baPWV) from October 2016 to January 2020. Concentrations of air pollutants including fine particles < 2.5μm aerodynamic diameter (PM2.5), inhalable particles < 10μm aerodynamic diameter (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3) measured by fixed ambient air monitoring stations were collected for short- (7-day) and long-term (365-day) exposure assessment. We used generalized estimating equations (GEEs) to analyze and further explored the modification effects between ASCVD and air pollutants. Seven hundred sixty-five participants were finally included and four hunderd sixty (60.1%) participants had a history of ASCVD. Based on the partial regression coefficients (β) and 95% confidence intervals (95% CI) calculated from GEEs using linear regression, each 10μg/m3 increase in long-term exposure to PM2.5 and PM10 was associated with 31.85cm/s (95% CI, 17.97 to 45.73) and 35.93cm/s (95% CI, 21.01to50.84) increase in baPWV. There was no association between short-term exposure to air pollution and arterial stiffness. Although no significant interaction effect was observed between air pollution and ASCVD, baPWV showed a greater increment in the subgroup without ASCVD. Long-term exposure to air pollution is closely associated with higher arterial stiffness in participants with and without ASCVD. Reducing air pollution exposure is essential in the primary and secondary prevention of ASCVD.

Direct-modulation optoelectronic oscillator for optical pulse and frequency comb generation

We report the generation of an optical pulse train with a 10 GHz repetition rate in a dual loop direct-modulation optoelectronic oscillator (OEO). Pulse generation is achieved using nonlinear compression in the OEO 5-km-long optical delay line. 3 ps pulses with a timing jitter of 13 fs are reported, while the OEO maintains a phase noise of −133dBc/Hz at 10 kHz from the carrier. Two architectures are compared experimentally and theoretically. A frequency comb with a 1.2 THz linewidth at −30dB is generated.

Design and Implementation of a Photonic-Based Electronic Warfare System

Nowadays, the Radio frequency (RF) Photonics become an inevitable candidate to address several military related potential applications including electronic warfare (EW), photonic signal processing (PSP), photonic-based RF transportation, and photonic communications. As part of this emerging technology development/requirement, we designed a photonic-based EW systems (PEWS) in the optisystem environment (later implemented using optoelectronic components) to extract various radar waveforms such as continuous wave (CW), pulsed wave, and frequency/phase modulated wave. All these radar waveforms are transmitted and captured by the proposed/implemented PEW system, and then processed to construct the radar signatures from its electromagnetic (EM) spectrum/signals. The key parameters of various waveforms generated and processed in our research work are varied, over the time, during the performance validation tests. The values of key parameters of the waveforms: RF CW signal frequencies, pulse repetition times (PRTs), pulse-widths, Barker code phase modulations, Frank code poly-phase modulations, sweep frequencies, and RF power levels; are 100 Hz through 8 GHz, 10 ms through 2 µs, 750 ns through 2 ns, 0o /80o, 0o /90o /180o /270o, and -84 dBm through 30 dBm, respectively. The details of PEWS design approaches, their implementation methodologies, and different performance validation experimental results are reported, and analyzed. The limitations, and possible immediate research contributions/requirements are also listed.

The Effect of 4-Month Treatment with Glycocalyx Dietary Supplement on Endothelial Glycocalyx Integrity and Vascular Function in Patients with Psoriasis

Psoriasis predisposes to cardiovascular dysfunction. We investigated whether glycocalyx dietary supplement (GDS), which contains glycosaminoglycans and fucoidan, improves endothelial glycocalyx and arterial stiffness in psoriatic patients. Fifty participants with psoriasis under biological agents were randomly assigned to GDS (n = 25) or placebo (n = 25) for 4 months. We measured at baseline and at follow-up: (a) perfused boundary region (PBR) of the sublingual microvessels (range 4 to 25 μm), a marker of endothelium glycocalyx integrity; (b) carotid–femoral pulse wave velocity (PWV-Complior SP-ALAM) and augmentation index (AIx), markers of arterial stiffness and (c) psoriasis area and severity index (PASI) score. Both groups displayed a similar decrease in PASI at four months (p &lt; 0.05), and no significant differences were found between groups (p &gt; 0.05). Compared to the placebo, participants in the GDS showed a greater percentage reduction in PBR4–25 μm (−9.95% vs. −0.87%), PBR 4–9 μm (−6.50% vs. −0.82%), PBR10–19 μm (−5.12% vs. −1.60%), PBR 20–25 μm (−14.9% vs. −0.31%), PWV (−15.27% vs. −4.04%) and AIx (−35.57% vs. −21.85%) (p &lt; 0.05). In the GDS group, the percentage reduction in PBR 4–25 μm was associated with the corresponding decrease in PWV (r = 0.411, p = 0.015) and AΙx (r = 0.481, p = 0.010) at follow-up. Four-month treatment with GDS improves glycocalyx integrity and arterial stiffness in patients with psoriasis. Clinical trial Identifier: NCT05184699.

Association between the oxidative balance score and estimated pulse wave velocity from the National Health and Nutrition Examination Survey (2005–2018)

BackgroundNo research report has been conducted to investigate the impact of oxidation balance score (OBS) on the estimated pulse wave velocity(ePWV).We aimed to examine the association between OBS and ePWV.MethodWe evaluated data for 13,073 patients from the National Health and Nutrition Examination Survey (NHANES). The exposure variable was OBS. The outcome variables was combination of ePWV and arterial stiffness.ResultsWe observed a significant negative correlation between OBS (Per 1SD increase) and ePWV in the gradually adjusted models. Based on the aforementioned results, a two-piecewise logistic regression adjusted model was subsequently employed to establish the association between OBS and elevated ePWV, and the inflection point was determined as 5. The increased risk of elevated ePWV (OR:0.70; 95%CI:0.51–0.94) gradually decreases with the increase of OBS on the left side of the inflection point; however, when OBS exceeds 5, this decrease in risk of elevated ePWV(OR:1.00; 95%CI:0.96–1.04) is no longer observed (P for log likelihood ratio test = 0.028).ConclusionsThere exists a significant association between OBS and ePWV in the context of American adults. Specifically, OBS exhibits a negative correlation with ePWV; however, when considering an elevated ePWV, a saturation effect is observed in relation to OBS.

The Relationship between Healthy Vascular Aging with the Mediterranean Diet and Other Lifestyles in the Spanish Population: The EVA Study

The aim of this study was to analyze the relationship between healthy vascular aging (HVA) and the Mediterranean diet alongside other lifestyles in a Spanish population aged 35 to 75 years without previous cardiovascular diseases. Methods: In this cross-sectional descriptive study, 501 individuals aged 35 to 75 years were recruited from five health centers by random sampling stratified by age and sex (55.90 ± 14.24 years, 49.70% men). HVA was determined in two steps. Step 1: Subjects with vascular damage to the carotid arteries or peripheral arterial disease were classified as non-HVA. Step 2: The study population was classified by age and sex using the percentiles of the vascular aging index (VAI), with VAI ≤p25 considered HVA and &gt;p25 considered non-HVA. The VAI was estimated using the following formula (VAI = (log (1.09) × 10 cIMT + log (1.14) cfPWV) × 39.1 + 4.76. Carotid–femoral pulse wave velocity (cfPWV) was measured with the SphygmoCor® device, and carotid intima–media thickness using Sonosite Micromax® ultrasound. Mediterranean diet (MD) adherence, alcohol and tobacco use were recorded through validated questionnaires. Physical activity was assessed with the ActiGraph-GT3X® accelerometer. Results: The mean VAI value was 61.23 ± 12.86 (men—63.47 ± 13.75 and women—59.04 ± 11.54; p &lt; 0.001). HVA was found in 18.9% (men—19.9% and women—17.8%). In the multiple regression analysis after adjusting for possible confounding factors, the mean VAI value showed a positive association with alcohol use (β = 0.020) and sedentary hours per week (β = 0.109) and a negative association with hours of activity per week (β = −0.102) and with the number of healthy lifestyles (β = −0.640). In the logistic regression analysis, after adjusting for possible confounding factors and compared to those classified as non-HVA, subjects classified as HVA were more likely to show MD adherence (OR = 0.571), do more than 26 h per week of physical activity (OR = 1.735), spend under 142 h per week being sedentary (OR = 1.696), and have more than two healthy lifestyles (OR = 1.877). Conclusion: The results of this study suggest that the more time spent doing physical activity and the less time spent in a sedentary state, the lower the vascular aging index and the greater the likelihood of being classified in the group of subjects with HVA.

SESAM Q-switched Dy-doped fluoride fiber laser at 3.1 µm

We report on a passive Q-switching laser operation of an in-band pumped Dy-doped zirconium fluoride fiber using a commercially available semiconductor saturable absorber mirror (SESAM). Stable Q-switching pulse trains with minimum pulse duration of 460 ns, highest repetition frequency of 206 kHz, and pulse energy up to 1.7 µJ are demonstrated.

Generation of Soliton Frequency Combs in NEMS.

In this study, we present an innovative approach leveraging combination internal resonances within a NEMS platform to generate mechanical soliton frequency combs (FCs) spanning a broad spectrum. In the time domain, the FCs take the form of a periodic train of narrow pulses, a highly coveted phenomenon within the realm of nonlinear wave-matter interactions. Our method relies on an intricate interaction among multiple vibration modes of a bracket-nanocantilever enabled by the strong nonlinearity of the electrostatic field. Through numerical simulation and experimental validation, we demonstrate that by amplifying the motions of the NEMS with the external electrostatic forcing tuned to excite the superharmonic resonance of order-n of the fundamental mode and exploiting combination internal resonances, we can generate multiple stable localized mechanical wave packets with different lobe sizes embodying soliton states I and II. This represents a significant breakthrough with profound implications for quantum computing and metrology.

The role of pulse wave analysis indexes for critically ill patients: a narrative review.

Arterial pulse wave analysis (PWA) is now established as a powerful tool to investigate the cardiovascular system, and several clinical studies have shown how PWA can provide valuable prognostic information over and beyond traditional cardiovascular risk factors. Typically these techniques are applied to chronic conditions, such as hypertension or aging, to monitor the slow structural changes of the vascular system which lead to important alterations of the arterial PW. However, their application to acute critical illness is not currently widespread, probably because of the high hemodynamic instability and acute dynamic alterations affecting the cardiovascular system of these patients. In this work we propose a review of the physiological and methodological basis of PWA, describing how it can be used to provide insights into arterial structure and function, cardiovascular biomechanical properties, and to derive information on wave propagation and reflection. The applicability of these techniques to acute critical illness, especially septic shock, is extensively discussed, highlighting the feasibility of their use in acute critical patients and their role in optimizing therapy administration and hemodynamic monitoring. The potential for the clinical use of these techniques lies in the ease of computation and availability of arterial blood pressure signals, as invasive arterial lines are commonly used in these patients. We hope that the concepts illustrated in the present review will soon be translated into clinical practice.

Prognostic impact of peripheral artery disease-related parameters in patients with acute coronary syndrome.

Lower extremity arterial disease (LEAD) and increased aortic stiffness are associated with higher mortality in patients with chronic coronary syndrome, while their prognostic significance after an acute coronary syndrome (ACS) is less known. We analyzed prevalence, clinical phenotypes and association of LEAD - assessed by the ankle-brachial index (ABI) - and increased aortic stiffness - assessed by the aortic pulse wave velocity (PWV) - with all-cause mortality and major adverse cardiovascular events (MACE) in patients admitted with an ACS. Among 270 patients admitted for ACS (mean age 67 years, 80% males), 41 (15%) had an ABI ≤0.9, with 14 of them (34%) presenting with intermittent claudication (symptomatic LEAD). Patients with symptomatic LEAD, compared with those with asymptomatic LEAD or without LEAD, had higher prevalence of cardiovascular risk factors, lower estimated glomerular filtration rate and higher high-sensitivity C-reactive protein. Patients with LEAD, either symptomatic or asymptomatic, more frequently presented with non-ST-elevation myocardial infarction and more frequently had multivessel coronary artery disease. Both symptomatic and asymptomatic LEAD were significantly associated with all-cause mortality after adjustment for confounders, including multivessel disease or carotid artery disease (hazard ratio 4.03, 95% confidence interval 1.61-10.08, P < 0.01), whereas PWV was not associated with the outcome in the univariable model. LEAD and PWV were not associated with a higher risk of MACE (myocardial infarction or unstable angina, stroke, or transient ischemic attack). LEAD, either clinical or subclinical, but not increased aortic stiffness, is an independent predictor of all-cause mortality in patients admitted for ACS.

Attosecond vortex pulse trains

The landscape of ultrafast structured light pulses has significantly advanced thanks to the ability of high-order harmonic generation (HHG) to translate the spatial properties of infrared laser beams to the extreme-ultraviolet (EUV) spectral range. In particular, the up-conversion of orbital angular momentum (OAM) has enabled the generation of high-order harmonics whose OAM scales linearly with the harmonic order and the topological charge of the driving field. Having a well-defined OAM, each harmonic is emitted as an EUV femtosecond vortex pulse. However, the order-dependent OAM across the harmonic comb precludes the synthesis of attosecond vortex pulses. Here we demonstrate a method for generating attosecond vortex pulse trains, i.e., a succession of attosecond pulses with a helical wavefront, resulting from the coherent superposition of a comb of EUV high-order harmonics with the same OAM. By driving HHG with a polarization tilt-angle fork grating, two spatially separated circularly polarized high-order harmonic beams with order-independent OAM are created. Our work opens the route towards attosecond-resolved light-matter interactions with two extra degrees of freedom, spin and OAM, which are particularly interesting for probing chiral systems and magnetic materials.

Longitudinal study of birthweight, blood pressure, and markers of arterial stiffness in children age six among the TIDES cohort.

Although some studies have observed an association between birthweight and cardiovascular disease in adulthood, fewer have investigated whether birthweight is linked to cardiovascular health in early childhood. This study assesses the association between birthweight and cardiovascular outcomes in children 6 years of age. Birthweight, blood pressure (BP), and markers of arterial stiffness in children, including brachial artery distensibility and carotid-femoral pulse wave velocity (cfPWV), were obtained from 324 participants in The Infant Development and the Environment Study, a prospective multisite pregnancy cohort. Birthweight was converted into sex-specific birthweight-for-gestational-age (bw/ga) z -scores based on the INTERGROWTH-21st standard. Following 2017 American Academy of Pediatrics guidelines, SBP and DBP were transformed into sex, age, and height-specific z -scores. Associations between birthweight and cardiovascular outcomes were assessed using nested multivariable linear regression models among the overall and sex-stratified samples. Among the overall sample, bw/ga z -score was positively associated with cfPWV [b = 0.11 m/s, 95% confidence interval (CI): 0.01 m/s, 0.21 m/s] in crude and adjusted models. No associations between birthweight and cardiovascular outcomes were detected among the sex-stratified analyses. Overall, birthweight was not related to cardiovascular outcomes in children 6 years old. However, infants born with a higher birthweight may be at risk for higher cfPWV in childhood. Early intervention in pregnant people at risk of delivering high birthweight infants may be warranted if results are replicated.

Efficacy of antihypertensive treatment for target organ protection in patients with masked hypertension (ANTI-MASK): a multicentre, double-blind, placebo-controlled trial

Masked hypertension is associated with target organ damage (TOD) and adverse health outcomes, but whether antihypertensive treatment improves TOD in patients with masked hypertension is unproven. In this multicentre, randomised, double-blind, placebo-controlled trial at 15 Chinese hospitals, untreated outpatients aged 30-70 years with an office blood pressure (BP) of <140/<90mm Hg and 24-h, daytime or nighttime ambulatory BP of ≥130/≥80, ≥135/≥85, or ≥120/≥70mm Hg were enrolled. Patients had ≥1 sign of TOD: electrocardiographic left ventricular hypertrophy (LVH), brachial-ankle pulse wave velocity (baPWV) ≥1400cm/s, or urinary albumin-to-creatinine ratio (ACR) ≥3.5mg/mmol in women and ≥2.5mg/mmol in men. Exclusion criteria included secondary hypertension, diabetic nephropathy, serum creatinine ≥176.8μmol/L, and cardiovascular disease within 6 months of screening. After stratification for centre, sex and the presence of nighttime hypertension, eligible patients were randomly assigned (1:1) to receive antihypertensive treatment or placebo. Patients and investigators were masked to group assignment. Active treatment consisted of allisartan starting at 80mg/day, to be increased to 160mg/day at month 2, and to be combined with amlodipine 2.5mg/day at month 4, if the ambulatory BP remained uncontrolled. Matching placebos were used likewise in the control group. The primary endpoint was the improvement of TOD, defined as normalisation of baPWV, ACR or LVH or a ≥20% reduction in baPWV or ACR over the 48-week follow-up. The intention-to-treat analysis included all randomised patients, the per-protocol analysis patients who fully adhered to the protocol, and the safety analysis all patients who received at least one dose of the study medication. This study is registered with ClinicalTrials.gov, NCT02893358. Between February 14, 2017, and October 31, 2020, 320 patients (43.1% women; mean age±SD 53.7±9.7 years) were enrolled. Baseline office and 24-h BP averaged 130±6.0/81±5.9mm Hg and 136±8.6/84±6.1mm Hg, and the prevalence of elevated baPWV, ACR and LVH were 97.5%, 12.5%, and 7.8%, respectively. The 24-h BP decreased on average (±SE) by 10.1±0.9/6.4±0.5mm Hg in 153 patients on active treatment and by 1.3±0.9/1.0±0.5mm Hg in 167 patients on placebo. Improvement of TOD occurred in 79 patients randomised to active treatment and in 49 patients on placebo: 51.6% (95% CI 43.7%, 59.5%) versus 29.3% (22.1, 36.5%; p<0.0001). Per-protocol and subgroup analyses were confirmatory. Adverse events were generally mild and occurred in 38 (25.3%) and 43 (26.4%) patients randomised to active treatment and placebo, respectively (p=0.83). Our results suggest that antihypertensive treatment improves TOD in patients with masked hypertension, highlighting the need of treatment. However, the long-term benefit in preventing cardiovascular complications still needs to be established. Salubris China.