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ABSTRACT A common feature in cohort studies is when there is a baseline measurement of the continuous follow‐up or outcome variable. Common examples include baseline measurements of physiological characteristics such as blood pressure or heart rate in studies where the outcome is post‐baseline measurement of the same variable. Methods incorporating the propensity score are increasingly being used to estimate the effects of treatments using observational studies. We examined six methods for incorporating the baseline value of the follow‐up variable when using propensity score matching or weighting. These methods differed according to whether the baseline value of the follow‐up variable was included or excluded from the propensity score model, whether subsequent regression adjustment was conducted in the matched or weighted sample to adjust for the baseline value of the follow‐up variable, and whether the analysis estimated the effect of treatment on the follow‐up variable or on the change from baseline. We used Monte Carlo simulations with 750 scenarios. While no analytic method had uniformly superior performance, we provide the following recommendations: first, when using weighting and the ATE is the target estimand, use an augmented inverse probability weighted estimator or include the baseline value of the follow‐up variable in the propensity score model and subsequently adjust for the baseline value of the follow‐up variable in a regression model. Second, when the ATT is the target estimand, regardless of whether using weighting or matching, analyze change from baseline using a propensity score that excludes the baseline value of the follow‐up variable. [ABSTRACT FROM AUTHOR]

Effective regulation of emotions is essential in coping with everyday stressors. Although cognitive reappraisal and acceptance are both commonly employed to downregulate negative emotions, they differ in many aspects. Their effectiveness in real‐life situations can also be influenced by prior stress or a person's trait preferences for certain emotion regulation (ER) strategies. In the present study, we compared the effectiveness of both ER strategies in a laboratory setting, while focussing on the effect of stress and trait moderators. Ninety‐eight healthy participants aged 18–40 were randomly divided into three groups with instructions to use reappraisal, acceptance, or nothing while viewing distressing pictures from the IAPS database. Half of the participants in each group underwent a laboratory stressor (socially evaluated cold pressor test) 20–30 min before the ER task. The effectiveness of ER was measured subjectively on the visual analog scale, and by measuring heart rate, skin conductance, and pupil responses. The data show that cognitive reappraisal lowered subjectively experienced negative emotion, while acceptance did not. These group differences were however not supported by psychophysiological indicators. Secondly, although the laboratory stressor elicited cortisol stress responses in our participants, we did not find any effect on ER. Furthermore, the data has not supported the moderation effect by trait reappraisal and acceptance. The present findings show that deliberate usage of ER strategies when viewing emotionally charged pictures leads to a decrease in experienced emotion. On the other hand, the effects of stress and trait moderators were not supported, therefore they may be smaller and more variable than expected. [ABSTRACT FROM AUTHOR]

Since assessing aerobic capacity is key to enhancing swimming performance, a simple and widely applicable technology should be developed. Therefore, we aimed to noninvasively visualize real‐time changes in sweat lactate (sLA) levels during swimming and investigate the relationship between lactate thresholds in sweat (sLT) and blood (bLT). This prospective study included 24 university swimmers (age: 20.7 s ± 1.8 years, 58% male) who underwent exercise tests at incremental speeds with or without breaks in a swimming flume to measure heart rate (HR), bLT, and sLT based on sLA levels using a waterproof wearable lactate sensor attached to the dorsal upper arm on two different days. The correlation coefficient and Bland–Altman methods were used to verify the similarities of the sLT with bLT and personal performance. In all tests, dynamic changes in sLA levels were continuously measured and projected onto the wearable device without delay, artifacts, or contamination. Following an initial minimal current response, with increasing speed the sLA levels increased substantially, coinciding with a continuous rise in HR. The speed at sLT strongly correlated with that at bLT (p < 0.01 and r = 0.824). The Bland–Altman plot showed a strong agreement (mean difference: 0.08 ± 0.1 m/s). This prospective study achieved real‐time sLA monitoring during swimming, even with vigorous movement. The sLT closely approximated bLT; both were subsequently validated for their relevance to performance. Highlights: A new technique using a wearable device can measure sweat lactate (sLA) levels during swimming without artifacts or contamination.Lactate threshold assessed using sLA dynamics is consistent with that calculated from blood samples.The current novel measurement method is expected to promote a personalized training regimen and simultaneous multi‐person measurements. [ABSTRACT FROM AUTHOR]

It is controversial whether people with vasovagal syncope (VVS) have abnormal autonomic responses at baseline and whether specific diagnostic manoeuvres have a diagnostic value. We investigated whether the pupillary light reflex and cardiac autonomic tests can be used to identify autonomic dysfunction in volunteers with a medical history of VVS. The study groups included 128 healthy volunteers, of whom 31 reported a history of typical VVS. The right pupil was evaluated using an automated, commercial infra‐red pupillometer under strict conditions. In addition to miosis and mydriasis kinetics, pupil diameters were measured. Heart rate variability at rest and heart rate changes to standing were quantified with high‐resolution electrocardiography and designated software. The demographic and clinical characteristics of both groups were statistically similar. Average constriction velocity (ACV) was significantly higher in VVS patients following a univariate analysis (3.83 ± 0.59 vs. 3.56 ± 0.73 mm/s, p = 0.042) and after correcting for potential confounders (p = 0.049). All other pupillometric and heart rate indices were comparable between groups. Patients with a history of VVS depict pupillary parasympathetic overactivity in response to light stimuli, manifested as increased ACV. The prognostic implications of this finding and the significance of using this simple clinical tool to identify patients who are at risk for developing frequent episodes of VVS or physical injuries following a syncope merits further study. [ABSTRACT FROM AUTHOR]

Aims: A population‐based pharmacokinetic (PK) modeling approach (PopPK) was used to investigate the impact of Roux‐en‐Y gastric bypass (RYGB) on the PK of (R)‐ and (S)‐carvedilol. We aimed to optimize carvedilol dosing for these patients utilizing a pharmacokinetic/pharmacodynamic (PK/PD) link model. Methods: PopPK models were developed utilizing data from 52 subjects, including nonobese, obese, and post‐ RYGB patients who received rac‐ carvedilol orally. Covariate analysis included anthropometric and laboratory data, history of RYGB surgery, CYP2D6 and CYP3A4 in vivo activity, and relative intestinal abundance of major drug‐ metabolizing enzymes and transporters. A direct effect inhibitory Emax pharmacodynamic model was linked to the PK model of (S)‐ carvedilol to simulate the changes in exercise‐ induced heart rate. Results: A 2‐compartmental model with linear elimination and parallel first‐order absorptions best described (S)‐carvedilol PK. RYGB led to a twofold reduction in relative oral bioavailability compared to nonoperated subjects, along with delayed absorption of both enantiomers. The intestinal ABCC2 mRNA expression increases the time to reach the maximum plasma concentration. The reduced exposure (AUC) of (S)‐carvedilol post‐RYGB corresponded to a 33% decrease in the predicted area under the effect curve (AUEC) for the 24‐hour β‐blocker response. Simulation results suggested that a 50‐mg daily dose in post‐RYGB patients achieved comparable AUC and AUEC to 25‐mg dose in nonoperated subjects. Conclusion: Integrated PK/PD modeling indicated that standard dosage regimens for nonoperated subjects do not provide equivalent β‐blocking activity in RYGB patients. This study highlights the importance of personalized dosing strategies to attain desired therapeutic outcomes in this patient cohort. [ABSTRACT FROM AUTHOR]

Aims: To investigate how a change in body position with light‐intensity physical activity (PA) 'snacks' (LIPAS, alternate sitting and standing, walking or standing continuously) compared with uninterrupted prolonged sitting affects glucose metabolism and heart rate variability (HRV) parameters in young adults with overweight and obesity. Materials and Methods: We conducted a four‐arm randomized controlled crossover trial. The following conditions were tested during an 8‐h simulated workday: uninterrupted prolonged sitting (SIT), alternate sitting and standing (SIT‐STAND; 2.5 h total), continuous standing (STAND), and continuous walking (1.0 mph; WALK). The primary outcome was to investigate how a change in body position (alternate sitting and standing, walking or standing continuously) compared with uninterrupted sitting affects mean 8‐h glucose metabolism. Secondary outcomes included the effects on 2‐h postprandial glucose concentrations, as well as on 8‐h/24‐h heart rate and HRV parameters, in the respective study arms. Capillary blood samples were drawn from an hyperemised earlobe in the fasted state and once every hour during each trial intervention by puncturing the earlobe with a lancet and collecting 20 μL of blood (Biosen S‐Line Lab+; EKF diagnostics, Barleben, Germany). HRV was assessed for 24 h including the 8‐h intervention phase, and a home phase by means of a Holter electrocardiogram. All participants received the same standardized non‐relativised breakfast and lunch during the four trial visits. Results: Seventeen individuals (eight women, mean age 23.4 ± 3.3 years, body mass index 29.7 ± 3.8 kg/m2, glycated haemoglobin level 34.8 ± 3.1 mmol/mol [5.4 ± 0.3%], body fat 31.8 ± 8.2%) completed all four trial arms. Compared with SIT (89.4 ± 6.8 mg/dL), 8‐h mean glucose was lower in all other conditions (p < 0.05) and this was statistically significant compared with WALK (86.3 ± 5.2 mg/dL; p = 0.034). Two‐hour postprandial glucose after breakfast was approximately 7% lower for WALK compared with SIT (p = 0.002). Furthermore, significant time × condition effects on HRV parameters favouring light‐intensity walking were observed (p < 0.001). Conclusions: Replacement and interruption of prolonged sitting with light‐intensity walking showed a significant blood glucose‐lowering effect and improved HRV during an 8‐h work environment in young adults with overweight and obesity. [ABSTRACT FROM AUTHOR]

Aims/Introduction: To evaluate the differences in cardiac autonomic function, cardiac structure and diastolic function between individuals with diabetic foot (DF) and those with diabetes but without DF. Materials and Methods: A total of 413 individuals with DF and 437 without DF who underwent a 24‐h electrocardiogram Holter and a Doppler echocardiogram were included. The heart rate variability parameters to evaluate cardiac autonomic function, and the indices for the assessment of cardiac structure and left ventricular (LV) diastolic function, including left atrium, LV posterior wall thickness, interventricular septum and E/e′ ratio, were measured or calculated. Propensity score matching was used for the sensitivity analysis to minimize potential imbalance. Results: In both the crude and propensity score matching analyses, significant differences were observed in heart rate variability between individuals with and without DF, as evidenced by lower standard deviation of the normal sinus interval, lower low‐frequency power/high‐frequency power ratio, lower standard deviation of the 5‐min average RR intervals, lower low‐frequency power, lower percentage of normal adjacent RR interval difference >50 ms, lower root mean square of successive RR interval differences and lower high‐frequency power (all P < 0.05). In multivariate analysis, DF showed an independent negative correlation with the aforementioned indices of heart rate variability (all P < 0.05). Individuals with DF showed higher left atrium, LV posterior wall thickness, interventricular septum and a higher E/e′ ratio than those without DF in the crude analysis (all P < 0.05), whereas these indices were no longer associated with DF in the multivariate analysis and the propensity score matching analyses. Conclusions: Cardiac autonomic modulation was more severely impaired in individuals with DF than in their counterparts without DF. There has been insufficient evidence to demonstrate the independent association of DF and LV diastolic dysfunction. [ABSTRACT FROM AUTHOR]

The midbrain dorsomedial periaqueductal grey column (dmPAG) is involved in the regulation of cardiovascular responses. Due to the presence of Gamma‐Aminobutyric acid (GABA) receptors in the dmPAG, this study aimed to investigate the role of GABAA receptors in the dmPAG on cardiovascular parameters and its possible peripheral mechanisms. The left femoral artery was cannulated, and systolic arterial pressure (SAP), mean arterial pressure (MAP) and heart rate (HR) were recorded using a Power lab system. Microinjection of saline, muscimol and bicuculline (BIC) was done using a stereotaxic device. Also, the peripheral mechanisms dependent on GABAA receptors in the dmPAG were evaluated by intravenous (i.v.) injection of hexamethonium (Hexa) and atropine (Atr) 5 min before the BIC. Results showed that BIC significantly increased ∆SAP, ∆MAP and ∆HR than the control group, but muscimol had no significant effect. Injection of Hex significantly attenuates the effect of BIC on ∆SAP and ∆MAP. Atr (i.v) significantly increased the ∆HR, and when injected before BIC microinjection, it did not affect the cardiovascular responses induced by BIC. These findings show that GABAA receptors of the dmPAG have inhibitory effects on the cardiovascular system, which are mostly mediated by the sympathetic system. [ABSTRACT FROM AUTHOR]

Physiologically based stress detection systems have proven to be effective in identifying different stress conditions in the body to determine the source of stress and be able to counteract it. However, some stress conditions have not been widely studied, including thermal stress, cognitive stress, and combined (thermal–cognitive) stress conditions, which are frequently encountered in work or school environments. In order to develop systems to detect and differentiate these conditions, it is necessary to identify the physiological indicators that characterize each of them. The present research aims to identify which physiological indicators (heart rate, respiratory rate, galvanic skin response, and local temperature) could differentiate different stress conditions (no‐stress, cognitive stress, thermal stress, and combined (thermal–cognitive) stress conditions). Thirty participants were exposed to cognitive, thermal, and combined stress sources while recording their physiological signals. The findings indicate that both mean heart rate and mean galvanic skin response identify moderate thermal and cognitive stress conditions as distinct from a no‐stress condition, yet they do not differentiate between the two stress conditions. Additionally, heart rate uniquely identifies the cognitive–thermal stress condition, effectively distinguishing this combined stress condition from the singular stress conditions and the no‐stress condition. Mean local temperature specifically signals thermal stress conditions, whereas mean respiratory rate accurately identifies cognitive stress conditions, with both indicators effectively separating these conditions from each other and from the no‐stress condition. This is the first basis for differentiating thermal and cognitive stress conditions through physiological indicators. Different sources of stress (thermal and cognitive) generate different physiological responses in the body. Mean heart rate, mean local temperature, mean respiratory rate, and mean galvanic skin response allow to differentiate between different stress conditions in the body. Physiological indicators can be used to develop signal‐based detection systems to identify different stress conditions. [ABSTRACT FROM AUTHOR]

Adapting to the ever‐changing demands of the environment requires a complex interplay between cognitive‐affective, neuronal, and autonomic processes. Vagally mediated heart rate variability (vmHRV) is positively associated with both cognitive‐affective functioning and prefrontal cortex (PFC) activity. Accordingly, the Neurovisceral Integration Model has posited a shared role of the PFC in the regulation of cognitive‐affective processes and autonomic nervous system (ANS) activity. While there are numerous correlational findings in this regard, no study so far has investigated whether the manipulation of PFC activity induces changes in vmHRV and cognitive‐affective processing in an inter‐dependent manner. In a sample of 64 participants, we examined the effects of continuous (cTBS; n = 21) and intermittent theta‐burst stimulation (iTBS; n = 20) compared to sham stimulation (n = 23) over the left dorsolateral PFC (dlPFC) on vmHRV and cognitive‐affective processing within an emotional stop‐signal task (ESST). Our results revealed that both resting vmHRV and vmHRV reactivity predicted cognitive‐affective processing. Furthermore, we found a dampening effect of cTBS on resting and on‐task vmHRV, as well as an enhancing effect of iTBS on ESST performance. Our results show no direct association between vmHRV changes and ESST performance alterations following stimulation. We interpret our results in the light of a hierarchical model of neurovisceral integration, suggesting a dynamical situation‐dependent recruitment of higher‐order cortical areas like the dlPFC in the regulation of the ANS. In conclusion, our results highlight the complex interplay between PFC activity, autonomic regulation, and cognitive‐affective processing, emphasizing the need for further research to understand the causal dynamics of the underlying neural mechanisms. Our study represents the first attempt to use repetitive transcranial magnet stimulation (rTMS) to test the relationship between prefrontal activity, vagally mediated heart rate variability (vmHRV) and cognitive‐affective processing, suggested by the Neurovisceral Integration Model. While we did not find hypothesized links between changes in vmHRV and cognitive‐affective processing induced by rTMS over the left dorsolateral prefrontal cortex (dlPFC), our results indicate flexible recruitment of higher‐order cortical areas, such as the left dlPFC in autonomic regulation. [ABSTRACT FROM AUTHOR]

This Committee Report provides methodological, interpretive, and reporting guidance for researchers who use measures of heart rate (HR) and heart rate variability (HRV) in psychophysiological research. We provide brief summaries of best practices in measuring HR and HRV via electrocardiographic and photoplethysmographic signals in laboratory, field (ambulatory), and brain‐imaging contexts to address research questions incorporating measures of HR and HRV. The Report emphasizes evidence for the strengths and weaknesses of different recording and derivation methods for measures of HR and HRV. Along with this guidance, the Report reviews what is known about the origin of the heartbeat and its neural control, including factors that produce and influence HRV metrics. The Report concludes with checklists to guide authors in study design and analysis considerations, as well as guidance on the reporting of key methodological details and characteristics of the samples under study. It is expected that rigorous and transparent recording and reporting of HR and HRV measures will strengthen inferences across the many applications of these metrics in psychophysiology. The prior Committee Reports on HR and HRV are several decades old. Since their appearance, technologies for human cardiac and vascular monitoring in laboratory and daily life (i.e., ambulatory) contexts have greatly expanded. This Committee Report was prepared for the Society for Psychophysiological Research to provide updated methodological and interpretive guidance, as well as to summarize best practices for reporting HR and HRV studies in humans. [ABSTRACT FROM AUTHOR]

The effect of stress on risk‐taking or risk‐averse behavior in decision‐making has been inconclusive in previous research, with few studies revealing the underlying neural mechanisms. This study employed event‐related potentials technique and combined a social cold pressor assessment test with a mental arithmetic task to induce stress responses, aiming to investigate the influence of exogenous stress on the risk decision‐making process. Stress induction results indicated that, in addition to raising heart rate and blood pressure, stress responses were accompanied by enhanced negative emotions, diminished positive emotions, and alterations in neural activity. The outcomes of risk decision‐making showed that stress did not significantly affect risk preference or time of choice but did reduce the feedback‐related negativity/reward positivity, with a particularly significant effect observed for large outcomes. Stress also altered the amplitude of the P3 component, with stress decreasing the P3 value for winning outcomes relative to losing outcomes. The study suggests that understanding how stress affects risk preference should consider the emotional valence induced by stress. Contrary to the reward sensitivity hypothesis, stress weakened reward sensitivity. Stress led to changes in the allocation of cognitive resources for outcome evaluation: compared to negative outcomes, stress reduced cognitive resources for positive outcomes, which might be related to the enhanced negative emotions induced by stress. The study highlights the importance of focusing on the subjective emotional experience induced by stress in future research on stress and risk decision‐making. We find that stress with negative emotions weakens reward sensitivity, which challenges the reward sensitivity hypothesis. Stress also modifies cognitive resource allocation for outcome evaluation: compared to negative outcomes, stress reduced cognitive resources for positive outcomes. This study underscores the significance of incorporating emotional experiences induced by stress into future investigations about stress and risk decision‐making. [ABSTRACT FROM AUTHOR]

Introduction: Innovative technologies, including virtual reality (VR), can be used for conducting VR exposure therapy (VRET) for individuals with psychiatric disorders, including claustrophobia. Unfortunately, there is a lack of studies on the effect of VR in treating claustrophobia in Arab countries, including Jordan. Therefore, this study aimed to evaluate the effect of VRET on minimising anxiety symptoms at 1 week post‐therapy and the physiological arousal measures (heart rate, O2 saturation and mean arterial pressure) of participants before and following therapy. Methods: A pre‐/post‐test one‐group design was used, and participants (N = 44) who suffered from claustrophobia from Al‐Zaytoonah University of Jordan were recruited. VRET was conducted using the Cave experience, which consists of four stages and was carried out in 4 to 6 sessions during the period from April to September 2023. Results: The findings revealed a significant difference between pre‐ and post‐VR simulation intervention for anxiety symptoms and physiological measures; in addition, the participants perceived the usability of VR therapy. Conclusion: This study suggested that VRET was effective in managing claustrophobia, particularly in minimising anxiety symptoms. Therefore, VRET can be integrated into the therapeutic methods for individuals with claustrophobia. Also, healthcare professionals, including mental health counsellors, can adopt such therapy in their management and treatment plan. [ABSTRACT FROM AUTHOR]

Leaves of the Khat plant are widely consumed in the Horn of Africa, Yemen and the Jazan region of Saudi Arabia. I have investigated the mode of cardiovascular and autonomic actions of the stimulant cathine from Khat in terms of direct or indirect adrenergic actions in anaesthetised male and female rats, and in isolated tissues. Male and female rats were anaesthetised with pentobarbitone and changes in diastolic blood pressure and cardioaccelerator responses were examined in vehicle‐treated or chemically sympathectomised rats. Cathine produced marked tachycardia and smaller blood pressure responses in vehicle‐treated animals, with significant rises in heart rate occurring at cathine (0.1 mg/kg). In sympathectomised rats, cardiac actions were greatly attenuated in both male and female animals, with no differences between male and female rats. Although pressor responses to cathine were relatively small, sympathectomy significantly reduced these responses in female, but not male, rats. In rat aorta and spleen, cathine produced almost no direct contractions. It is concluded that cathine acts predominantly indirectly, presumably by the release of noradrenaline, in both male and female rats to produce cardiovascular actions. This may have implications for adverse cardiovascular actions of consumption of the plant Khat, particularly with dried Khat, in which actions of cathine may predominate over those of cathinone. [ABSTRACT FROM AUTHOR]

Studies have focused on the negative effects of anger on driving performance, but insufficient research has addressed intervention methods to reduce these emotional effects. This research investigated how music mitigates the deterioration of driving performance associated with angry emotions in a simulated car‐following task. Forty‐three licensed drivers participated in this study, and they were randomly separated into two groups: an intervention group and a control group. First, all the participants completed a car‐following task involving neutral arousal. Then, both groups completed the car‐following task after the anger arousal task. The intervention group drove while listening to relaxing music, but the control group did not. Driving performance and electrocardiographic data were recorded. The results showed that participants who listened to relaxing music had significantly shorter braking reaction times and greater heart rate variability (HRV) than did those who did not listen to music. Relaxing music can reduce driving anger and improve driving behavior. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to develop and evaluate a novel cardiovascular MR sequence, MyoFold, designed for the simultaneous quantifications of myocardial tissue composition and wall motion. Methods: MyoFold is designed as a 2D single breathing‐holding sequence, integrating joint T1/T2 mapping and cine imaging. The sequence uses a 2‐fold accelerated balanced SSFP (bSSFP) for data readout and incorporates electrocardiogram synchronization to align with the cardiac cycle. MyoFold initially acquires six single‐shot inversion‐recovery images, completed during the diastole of six successive heartbeats. T2 preparation (T2‐prep) is applied to introduce T2 weightings for the last three images. Subsequently, over the following six heartbeats, segmented bSSFP is performed for the movie of the entire cardiac cycle, synchronized with an electrocardiogram. A neural network trained using numerical simulations of MyoFold is used for T1 and T2 calculations. MyoFold was validated through phantom and in vivo experiments, with comparisons made against MOLLI, SASHA, T2‐prep bSSFP, and the conventional cine. Results: In phantom studies, MyoFold exhibited a 10% overestimation in T1 measurements, whereas T2 measurements demonstrated high accuracy. In vivo experiments revealed that MyoFold T1 had comparable accuracy to SASHA and precision similar to MOLLI. MyoFold demonstrated good agreement with T2‐prep bSSFP in myocardial T2 measurements. No significant differences were observed in the quantification of left‐ventricle wall thickness and function between MyoFold and the conventional cine. Conclusion: MyoFold presents as a rapid, simple, and multitasking approach for quantitative cardiovascular MR examinations, offering simultaneous assessment of tissue composition and wall motion. The sequence's multitasking capabilities make it a promising tool for comprehensive cardiac evaluations in clinical settings. [ABSTRACT FROM AUTHOR]

Background: During urodynamic testing (UT), patients may experience emotions such as embarrassment, discomfort, irritability, and tension, which can cause anxiety. Aromatherapy is a complementary and alternative treatment that may be employed in clinical settings to alleviate patients' anxiety before invasive procedures. Objectives: The aim of this study was to determine the effect of aromatherapy on patients' anxiety and cortisol levels during UT. Materials and Methods: The sample of this single‐center, prospective, two‐armed, randomized controlled clinical study consisted of 98 patients undergoing UT. Patients were randomly assigned to the intervention group (n = 49) and the control group (n = 49). The anxiety level was assessed using the state‐trait anxiety inventory (STAI), and measured with physiological responses to anxiety, such as changes in systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), respiratory rate (RR), peripheral oxygen saturation (SpO2), and cortisol levels, pre and post‐UT. Aromatherapy was applied to the intervention group starting 5 min before UT and continuing throughout the testing. The control group received routine treatment and care. Data were analyzed using Pearson's χ2, dependent samples t‐tests, and independent samples t‐tests. Results: In the study, post‐UT anxiety in the intervention group was significantly lower than in the control group (p < 0.001), while SpO2 was higher (p = 0.021). In the study group, post‐UT anxiety (p < 0.001), HR (p = 0.000), and cortisol levels (p = 0.005) decreased compared to pre‐UT, whereas in the control group, anxiety (p < 0.001) and HR (p = 0.000) decreased, and SBP (p = 0.010) and RR (p = 0.004) increased. Conclusions: Aromatherapy during UT positively influenced both the psychological and physiological responses to anxiety. [ABSTRACT FROM AUTHOR]

Objectives: To assess first‐trimester prognosis when an early pregnancy sonogram demonstrates a normal embryonic heart rate and to determine how a number of risk factors affect prognosis. Methods: Our study population consisted of 6597 first‐trimester scans with gestational age (GA) ≤ 7.0 weeks (all with crown‐rump length [CRL] <10 mm), normal embryonic heart, and known first‐trimester outcome. We recorded GA; CRL; heart rate; first‐trimester outcome; maternal age; presence, absence, and size of subchorionic hematoma; presence or absence of vaginal bleeding; and presence, absence, and size of uterine fibroids. We assessed first‐trimester outcome in the study population and subsets based on the above data. Results: First‐trimester outcome was successful in 6030 of the 6597 cases (91.4%). The prognosis was somewhat worse with each of the following risk factors: maternal age ≥35 years, large subchorionic hematoma, and large or multiple uterine fibroids (P <.02, chi‐squared or Cochran's test for trend, for all of these items). The rate of successful outcome was in the range of 83–88% with each of these risk factors and 93.8% in the absence of any of these factors. Conclusions: The presence of a normal embryonic heart rate on an early first‐trimester sonogram is a reassuring finding, indicating a likelihood of good first‐trimester outcome of at least 83% even in the presence of risk factors, and of over 90% in the absence of such factors. [ABSTRACT FROM AUTHOR]

Montmorency cherry (MC) can improve endurance performance, but optimal pre‐exercise timing of supplementation and influence of training status on efficacy are unknown. We investigated the effect of MC concentrate ingestion between 30‐ and 150‐min pre‐exercise in trained and recreational cyclists on 15‐km time trial (TT) performance and exercise economy. Twenty participants (10 recreationally active, RA; 10 trained, T) completed 10 min of steady‐state exercise (SSE) at 40%Δ (SSE) and a TT on four separate occasions following an unsupplemented (US), 30‐, 90‐ or 150‐min pre‐exercise Montmorency cherry concentrate (MCC) supplementation conditions (MCC30/90/150min). Venous and capillary blood samples were taken at regular intervals pre‐ and post‐SSE and TT. MCC significantly improved TT performance, but not exercise economy. The greatest improvement in performance occurred following MCC90min compared to US (US 1603.1 ± 248 s vs. MCC90min 1554.8 ± 226.7 s, 2.83% performance improvement). Performance was significantly enhanced for trained (US 1496.6 ± 173.1 s vs. MCC90min 1466.8 ± 157.6 s) but not recreationally active participants. Capillary [lactate] and heart rate were significantly greater during the TT for the 90‐min dose timing (p < 0.05). In the MCC30min and MCC90min conditions, plasma ferulic (US 8.71 ± 3.22 nmol. L−1 vs. MCC30min 15.80 ± 8.69 nmol. L−1, MCC90min 12.65 ± 4.84 nmol. L−1) and vanillic acid (US 25.14 ± 10.91 nmol.L−1 vs. MCC30min 153.07 ± 85.91 nmol. L−1, MCC90min 164.58 ± 59.06 nmol. L−1) were significantly higher pre‐exercise than in US and MCC150min conditions (p < 0.05). There was no significant change in muscle oxygenation status or plasma nitrite/nitrate concentration. MCC supplementation enhanced endurance exercise performance optimally when consumed ∼90 min pre‐exercise producing maximal plasma phenolic metabolites during exercise. The ergogenic effect was greater for trained participants. [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF) is a rarely reported arrhythmia in otherwise healthy newborn foals, with a single case of cardioversion using procainamide administration described in the literature. Two neonatal Thoroughbred colts were presented to an equine hospital because of an irregularly irregular tachyarrhythmia and poor latching when trying to nurse. History, physical examination, and initial diagnostic testing including ECG and echocardiography confirmed AF without structural heart disease. The 1st foal converted into normal sinus rhythm after treatment with IV metoprolol and quinidine. The 2nd foal converted to normal sinus rhythm after a single IV dose of metoprolol, intended for rate control. Demeanor and nursing behavior improved markedly after conversion. The 2 foals had normal heart rates and sinus rhythm that persisted for 6 weeks until euthanasia in the 1st foal and for 2 years in the 2nd foal. Rate control and cardioversion should be considered as a treatment for persistent lone AF in neonatal foals. [ABSTRACT FROM AUTHOR]

ABSTRACT Aims Methods and results Conclusions In the absence of randomized trial evidence, we performed a large observational analysis of the association between beta‐blocker (BB) use and clinical outcomes in patients with heart failure (HF) and mildly reduced (HFmrEF) and preserved ejection fraction (HFpEF).We pooled individual patient data from four large HFmrEF/HFpEF trials (I‐Preserve, TOPCAT, PARAGON‐HF, and DELIVER). The primary outcome was the composite of cardiovascular death or HF hospitalization. Among the 16 951 patients included, the mean left ventricular ejection fraction (LVEF) was 56.8%, and 13 400 (79.1%) had HFpEF (LVEF ≥50%). Overall, 12 812 patients (75.6%) received a BB. The median bisoprolol‐equivalent dose of BB was 5.0 (Q1–Q3: 2.5–5.0) mg with BB continuation rates of 93.1% at 2 years (in survivors). The unadjusted hazard ratio (HR) for the primary outcome did not differ between BB users and non‐users (HR 0.98, 95% confidence interval [CI] 0.91–1.05), but the adjusted HR was lower in BB users than non‐users (0.81, 95% CI 0.74–0.88), and this association was maintained across LVEF (pinteraction = 0.88). In subgroup analyses, the adjusted risk of the primary outcome was similar in BB users and non‐users with or without a history of myocardial infarction, hypertension, or a baseline heart rate <70 bpm. By contrast, a better outcome with BB use was seen in patients with atrial fibrillation compared to those without atrial fibrillation (pintreraction = 0.02).In this observational analysis of non‐randomized BB treatment, there was no suggestion that BB use was associated with worse HF outcomes in HFmrEF/HFpEF, even after extensive adjustment for other prognostic variables. [ABSTRACT FROM AUTHOR]

Highlights Acute ingestion of exogenous ketone supplements in the form of a (R)‐3‐hydroxybutyl (R)‐3‐hydroxybutyrate (R‐BD R‐βHB) ketone monoester (KME) can attenuate declines in oxygen availability during hypoxic exposure and might impact cognitive performance at rest and in response to moderate‐intensity exercise. In a single‐blind randomized crossover design, 16 males performed assessments of cognitive performance before and during hypoxic exposure with moderate exercise [2 × 20 min weighted ruck (∼22 kg) at 3.2 km/h at 10% incline] in a normobaric altitude chamber (4572 m, 11.8% O2). The R‐BD R‐βHB KME (573 mg/kg) or a calorie‐ and taste‐matched placebo (∼50 g maltodextrin) were co‐ingested with 40 g of dextrose before exposure to hypoxia. The R‐βHB concentrations were rapidly elevated and sustained (>3 mM; P < 0.001) by KME. The decline in oxygen saturation during hypoxic exposure was attenuated in KME conditions by 2.4%–4.2% (P < 0.05) compared with placebo. Outcomes of cognitive performance tasks, in the form of the Defense Automated Neurobehavioral Assessment (DANA) code substitution task, the Stroop color and word task, and a shooting simulation, did not differ between trials before and during hypoxic exposure. These data suggest that the acute exogenous ketosis induced by KME ingestion can attenuate declining blood oxygen saturation during acute hypoxic exposure both at rest and during moderate‐intensity exercise, but this did not translate into differences in cognitive performance before or after exercise in the conditions investigated. What is the central question of this study? Can exogenous ketosis act as a countermeasure to declines in blood oxygen saturation and cognitive performance during acute hypoxic exposure while performing a weighted ruck exercise? What is the main finding and its importance? Acute exogenous ketosis via ingestion of a drink containing the (R)‐3‐hydroxybutyl (R)‐3‐hydroxybutyrate ketone monoester prior to acute hypoxic exposure attenuated hypoxia‐induced declines in blood oxygen saturation but had no effect on cognitive performance during exercise. What is the central question of this study?Can exogenous ketosis act as a countermeasure to declines in blood oxygen saturation and cognitive performance during acute hypoxic exposure while performing a weighted ruck exercise?What is the main finding and its importance?Acute exogenous ketosis via ingestion of a drink containing the (R)‐3‐hydroxybutyl (R)‐3‐hydroxybutyrate ketone monoester prior to acute hypoxic exposure attenuated hypoxia‐induced declines in blood oxygen saturation but had no effect on cognitive performance during exercise. [ABSTRACT FROM AUTHOR]

The opening and closing dynamics of the aortic valve (AV) has a strong influence on haemodynamics in the aortic root, and both play a pivotal role in maintaining normal physiological functions of the valve. The aim of this study was to establish a subject‐specific fluid–structure interaction (FSI) workflow capable of simulating the motion of a tricuspid healthy valve and the surrounding haemodynamics under physiologically realistic conditions. A subject‐specific aortic root was reconstructed from magnetic resonance (MR) images acquired from a healthy volunteer, whilst the valve leaflets were built using a parametric model fitted to the subject‐specific aortic root geometry. The material behaviour of the leaflets was described using the isotropic hyperelastic Ogden model, and subject‐specific boundary conditions were derived from 4D‐flow MR imaging (4D‐MRI). Strongly coupled FSI simulations were performed using a finite volume‐based boundary conforming method implemented in FlowVision. Our FSI model was able to simulate the opening and closing of the AV throughout the entire cardiac cycle. Comparisons of simulation results with 4D‐MRI showed a good agreement in key haemodynamic parameters, with stroke volume differing by 7.5% and the maximum jet velocity differing by less than 1%. Detailed analysis of wall shear stress (WSS) on the leaflets revealed much higher WSS on the ventricular side than the aortic side and different spatial patterns amongst the three leaflets. [ABSTRACT FROM AUTHOR]

Vagally‐mediated heart rate variability (vmHRV) is a physiological index reflecting parasympathetic activity that has been linked to emotion regulation (ER) capacity. However, very limited research has examined associations of physiological indices of regulation such as vmHRV with emotional functioning in daily life. The few studies that exist have small samples sizes and typically focus on only a narrow aspect of ER or emotional functioning. In this study, we examined associations between vmHRV assessed in the laboratory and emotional/mental health functioning in daily life using a 7‐day ecological momentary assessment design in 303 adult community participants. We hypothesized that higher resting vmHRV would be associated with higher positive affect (PA), lower negative affect (NA), less affective variability, greater well‐being, fewer dysphoria symptoms, greater use of engagement ER strategies, and less use of avoidance ER strategies, as assessed in daily life. Results revealed that higher resting vmHRV in the laboratory (as indexed by both high frequency heart rate variability, HF‐HRV, and the root mean of successive square deviations between heart beats, RMSSD) was significantly associated with less frequent use of avoidance ER strategies in daily life. Theoretical and clinical implications are discussed, including the association of vmHRV with negatively valenced, rather than positively valenced, daily life experiences. [ABSTRACT FROM AUTHOR]

Objective Procedures Results Conclusions Investigate the tolerance, stability, and efficacy of topical 0.1% and 1% atropine in cats.Six cats underwent two trials separated by a 2‐week washout period. One drop of artificial tears was placed in one randomly selected eye (control), and one drop of either 0.1% atropine (Trial I) or 1% atropine (Trial II) was placed in the other eye. Immediate adverse effects were recorded for severity (0–3) and duration (seconds). Horizontal pupil diameter (HPD), pupillary light reflexes (PLRs), intraocular pressure (IOP), Schirmer tear test‐1 (STT‐1), and heart rate (HR) were monitored at baseline then 8 h post‐administration. PLRs were assessed for a total of 72 h. Stability was assessed weekly for 1 month in room temperature and refrigerated conditions, evaluating solution clarity, pH, and drug concentrations.Adverse effects had a significantly lower severity score and shorter duration with 0.1% versus 1% atropine (severity 1.2 ± 0.4 vs. 2.5 ± 0.5, p = .010; duration 107.5 ± 53.3 vs. 293.3 ± 106.5 s, p = .009). HPD was significantly greater than baseline measurements as early as 40 min for both atropine formulations. Pupils were non‐responsive for a significantly shorter duration with 0.1% versus 1% atropine (median 7 h vs. 47.5 h, p = .031). Compared with control eyes, IOP was significantly elevated by 1% atropine (p = .021) but not 0.1% atropine (p = .502). No significant differences were noted in STT‐1 and HR measurements. Both solutions were stable in room temperature and refrigerated conditions for 1 month.Diluted 0.1% atropine was stable and better tolerated by cats, offering a potential alternative to feline patients that experience adverse effects from topical 1% atropine. [ABSTRACT FROM AUTHOR]

Aims Materials and Methods Results Conclusions To investigate the relationship between cardiorespiratory fitness (CRF) and liver fat content (LFC) in community‐based participants and highlight their relationship in people with different body mass indices (BMIs).Using UK Biobank data, CRF was estimated with bicycle ergometer fitness testing and was evaluated based on physical work capacity at 75% maximum heart rate (PWC75%). LFC was quantified through liver proton density fat fraction (PDFF) on magnetic resonance imaging. Multivariate linear regression models were used to analyse the associations of CRF and BMI with absolute reduction and percentage change in PDFF (%).In total, 5765 participants with a mean age of 55.57 years and a median (range) follow‐up of 10.7 (4.0–17.7) years were included. Compared with the lowest PWC75% tertile, the absolute reduction and percentage change in PDFF in the highest PWC75% tertile were −0.450 (95% confidence interval [CI] −0.699 to −0.192) and −4.152 (95% CI −6.044 to −2.104), respectively. These associations were independent of BMI, and individuals with obesity and normal weight had the largest absolute reduction and percentage change in LFC, respectively (p for interaction <0.001). Joint analysis showed that PWC75% and BMI had a negative dose–response relationship with PDFF. These associations were consistent in different sex and age subgroups (p for interaction >0.05).There was a significant negative association between CRF and LFC, and this association was independent of BMI. The results of this study strongly recommend improving CRF to mitigate LFC. [ABSTRACT FROM AUTHOR]

Background Methods Results Conclusion Heart failure (HF) patients are at constant risk of decompensation, and urgent hospital admissions can be life‐threatening events. Monitoring biological variables has been proved to be an important mechanism to anticipate decompensations. TriageHF is a validated diagnostic algorithm tool available on Medtronic® cardiac implantable electronic devices that combines physiological data to stratify a patient's risk of HF hospitalization in the following 30 days in low, medium or high risk. We aimed to evaluate the utility of TriageHF algorithm to predict the occurrence of acute clinical decompensation events (ACDE), including HF and non‐HF cardiovascular events, within a 30‐day period in a population of HF patients with reduced ejection fraction.We reviewed the transmissions received by the Medtronic® Carelink™ Network between August 2022 and July 2023. The heart failure risk status (HFRS) and the device parameters contributing to that risk, from the previous 30 days, were collected, along with the occurrence of ACDEs within 30 days.We retrospectively assessed 207 transmissions from the 64 patients included in the study. Among the 93 medium HFRS transmissions, 16 (17.2%) resulted in ACDEs. For the 21 high HFRS transmissions, 10 (47.6%) resulted in ACDEs. Considering the ACDEs, 60.7% were preceded by an alarm‐initiated transmission. Except for heart rate variability, each diagnostic parameter demonstrated effectiveness in stratifying risk for ACDEs. Optivol® and the Combined Heart Rhythm showed independent association with ACDEs (p < .001). Patients with medium and high HFRS were, respectively, 8.6 and 29.1 times more likely to experience an ACDE in the next 30 days than low risk patients. A medium‐high HFRS conferred a sensitivity of 92.9% and a NPV of 97.8% for an ACDE.TriageHF is a useful method for predicting ACDEs and has the potential to trigger medical actions to prevent hospitalizations. [ABSTRACT FROM AUTHOR]

The article explores the role of sustained elevated carbon dioxide levels in initiating plasticity in humans exposed to mild intermittent hypoxia. The authors argue that previous studies have shown inconsistent results in initiating long-term facilitation (LTF) in humans, and they propose that sustained carbon dioxide levels are necessary for the initiation and manifestation of LTF. They provide evidence from experiments showing that LTF is evident when carbon dioxide levels are sustained above baseline during and after exposure to mild intermittent hypoxia. The article also discusses the potential therapeutic benefits of this treatment in individuals with sleep apnea, including improved upper airway patency and reduced need for continuous positive airway pressure (CPAP) treatment. The authors are further investigating the effects of this treatment on responses to tactile pressure and auditory noise, as well as its impact on blood pressure. More research is needed to fully understand the mechanisms and determine the optimal dosage and timing of administration. [Extracted from the article]

The perception of signals from within the body, known as interoception, is increasingly recognized as a prerequisite for physical and mental health. This study is dedicated to the development of effective technological approaches for enhancing interoceptive abilities. We provide evidence of the effectiveness and practical feasibility of a novel real‐time haptic heartbeat supplementation technology combining principles of biofeedback and sensory augmentation. In a randomized controlled study, we applied the developed naturalistic haptic feedback on a group of 30 adults, while another group of 30 adults received more traditional real‐time visual heartbeat feedback. A single session of haptic, but not visual heartbeat feedback resulted in increased interoceptive accuracy and confidence, as measured by the heart rate discrimination task, and in a shift of attention toward the body. Participants rated the developed technology as more helpful and pleasant than the visual feedback, thus indicating high user satisfaction. The study highlights the importance of matching sensory characteristics of the feedback provided to the natural bodily prototype. Our work suggests that real‐time haptic feedback might be a superior approach for strengthening the mind–body connection in interventions for physical and mental health. [ABSTRACT FROM AUTHOR]

Smartwatches and home‐based blood pressure (BP) devices have permitted easy use of heart rate variability (HRV) and BP to identify the recovery status of users after acute exercise training. The reproducibility of HRV and BP after exercise in healthy young participants is not well known. Eighteen participants (age 27 ± 6 years, female n = 8) performed test and retest aerobic exercises (cycling, 30 min, 60% of peak workload, W) and a control session in randomized order. RMSSD, high and low‐frequency power of RR intervals, and BP were measured at rest and 30–60 min after interventions. The relative reproducibility was assessed by the intraclass correlation coefficient (ICC) and 95% confidence interval (95% CI). The absolute reproducibility was evaluated using the coefficient of variation (CV%). HRV indices revealed moderate‐to‐excellent reproducibility at rest (ICC 0.81–0.86; 95% CI 0.53–0.95) but not after exercise (ICC −0.06 to 0.60; 95% CI −1.85 to 0.85). Systolic BP had a good‐to‐excellent reproducibility before (ICC 0.93; 95% CI 0.81–0.98, CV% 4.2) and after exercise (ICC 0.93; 95% CI 0.81–0.97, CV% 4.2). The reproducibility of HRV indices is poor after exercise in young participants. However, the reproducibility of BP is excellent at rest and after aerobic exercise. [ABSTRACT FROM AUTHOR]

The present study investigated the impact of central α2‐adrenergic mechanisms on sympathetic action potential (AP) discharge, recruitment and latency strategies. We used the microneurographic technique to record muscle sympathetic nerve activity and a continuous wavelet transform to investigate postganglionic sympathetic AP firing during a baseline condition and an infusion of a α2‐adrenergic receptor agonist, dexmedetomidine (10 min loading infusion of 0.225 µg kg−1; maintenance infusion of 0.1–0.5 µg kg h−1) in eight healthy individuals (28 ± 7 years, five females). Dexmedetomidine reduced mean pressure (92 ± 7 to 80 ± 8 mmHg, P < 0.001) but did not alter heart rate (61 ± 13 to 60 ± 14 bpm; P = 0.748). Dexmedetomidine reduced sympathetic AP discharge (126 ± 73 to 27 ± 24 AP 100 beats−1, P = 0.003) most strongly for medium‐sized APs (normalized cluster 2: 21 ± 10 to 5 ± 5 AP 100 beats−1; P < 0.001). Dexmedetomidine progressively de‐recruited sympathetic APs beginning with the largest AP clusters (12 ± 3 to 7 ± 2 clusters, P = 0.002). Despite de‐recruiting large AP clusters with shorter latencies, dexmedetomidine reduced AP latency across remaining clusters (1.18 ± 0.12 to 1.13 ± 0.13 s, P = 0.002). A subset of six participants performed a Valsalva manoeuvre (20 s, 40 mmHg) during baseline and the dexmedetomidine infusion. Compared to baseline, AP discharge (Δ 361 ± 292 to Δ 113 ± 155 AP 100 beats−1, P = 0.011) and AP cluster recruitment elicited by the Valsalva manoeuvre were lower during dexmedetomidine (Δ 2 ± 1 to Δ 0 ± 2 AP clusters, P = 0.041). The reduction in sympathetic AP latency elicited by the Valsalva manoeuvre was not affected by dexmedetomidine (Δ –0.09 ± 0.07 to Δ –0.07 ± 0.14 s, P = 0.606). Dexmedetomidine reduced baroreflex gain, most strongly for medium‐sized APs (normalized cluster 2: –6.0 ± 5 to –1.6 ± 2 % mmHg−1; P = 0.008). These data suggest that α2‐adrenergic mechanisms within the central nervous system modulate sympathetic postganglionic neuronal discharge, recruitment and latency strategies in humans. Key points: Sympathetic postganglionic neuronal subpopulations innervating the human circulation exhibit complex patterns of discharge, recruitment and latency. However, the central neural mechanisms governing sympathetic postganglionic discharge remain unclear.This microneurographic study investigated the impact of a dexmedetomidine infusion (α2‐adrenergic receptor agonist) on muscle sympathetic postganglionic action potential (AP) discharge, recruitment and latency patterns.Dexmedetomidine infusion inhibited the recruitment of large and fast conducting sympathetic APs and attenuated the discharge of medium sized sympathetic APs that fired during resting conditions and the Valsalva manoeuvre.Dexmedetomidine infusion elicited shorter sympathetic AP latencies during resting conditions but did not affect the reductions in latency that occurred during the Valsalva manoeuvre.These data suggest that α2‐adrenergic mechanisms within the central nervous system modulate sympathetic postganglionic neuronal discharge, recruitment and latency strategies in humans. [ABSTRACT FROM AUTHOR]

All animal species, from arthropods to vertebrates, must deal with occasional stressors in their lives, though most research on this has been focused on vertebrates. Meanwhile, our understanding of stress reactions in arthropod species like spiders is nascent. In the United States, a non‐native orb‐weaving spider, Trichonephila clavata (‘jorō’ spider), is spreading as is its already‐established cousin in the United States, T. clavipes (golden silk spider). Prior study has revealed how these two species have a unique behavioural reaction to physical stressors, whereby they remain in a thanatosis state for a prolonged period compared with other species. Here, we investigate the physiological stress reactions of these Trichonephila spiders by evaluating how each species' dorsal vessel contractions (heart rates) become elevated after being subjected to a non‐lethal stressor. For comparison, we also evaluate two similarly‐sized orb weavers, Argiope aurantia (garden spider) and A. trifasciata (banded garden spider). We record baseline heart rates of inactive, resting, spiders in our lab, then restrain them under an electronic, ‘optocardiographic’, sensor for 10 min, to record their ‘stressed’ heart rates. Argiope aurantia has a pronounced heart rate elevation, for reasons unknown. We observe that all spider heart rates increase during restraint, though each has a species‐specific pattern of elevation over time under restraint. Notably, heart rates of both Trichonephila spiders are less variable under stress, since they tend not to struggle during restraint. Meanwhile, both Argiope spiders frequently struggle, leading to marked fluctuations in cardiac output. The stress reactions of Trichonephila spiders could be characterized as ‘even‐tempered’, which may factor into their ability to live in habitats with frequent disturbances. [ABSTRACT FROM AUTHOR]

Relative uteroplacental insufficiency of labor (RUPI‐L) is a clinical condition that refers to alterations in the fetal oxygen “demand–supply” equation caused by the onset of regular uterine activity. The term RUPI‐L indicates a condition of “relative” uteroplacental insufficiency which is relative to a specific stressful circumstance, such as the onset of regular uterine activity. RUPI‐L may be more prevalent in fetuses in which the ratio between the fetal oxygen supply and demand is already slightly reduced, such as in cases of subclinical placental insufficiency, post‐term pregnancies, gestational diabetes, and other similar conditions. Prior to the onset of regular uterine activity, fetuses with a RUPI‐L may present with normal features on the cardiotocography. However, with the onset of uterine contractions, these fetuses start to manifest abnormal fetal heart rate patterns which reflect the attempt to maintain adequate perfusion to essential central organs during episodes of transient reduction in oxygenation. If labor is allowed to continue without an appropriate intervention, progressively more frequent, and stronger uterine contractions may result in a rapid deterioration of the fetal oxygenation leading to hypoxia and acidosis. In this Commentary, we introduce the term relative uteroplacental insufficiency of labor and highlight the pathophysiology, as well as the common features observed in the fetal heart rate tracing and clinical implications. [ABSTRACT FROM AUTHOR]

Low‐dimensional van der Waals materials (vdWMs) have attracted worldwide interest on account of numerous advantages including self‐passivated surface, high carrier mobility, excellent flexibility, etc. Among multiple vdWMs, Sb2Se3 stands out due to its high light absorption coefficient, environmentally friendly components, excellent stability, and abundant reserve. However, limited effective wavelength range and unscalable preparation have been obstinate issues standing in the way of further development. Herein, pulsed‐laser deposition (PLD) has been developed for synthesizing Sb2Se3 nanofilms, and wafer‐scale deposition has been realized. The PLD‐derived Sb2Se3 photodetector demonstrates broadband photoresponse across UV to NIR. First‐principles calculations have determined that this is because the formation of Se vacancies can result in a reduction of the bandgap. Upon 635 nm illumination, an optimal responsivity of 2.68 A W−1 has been achieved, corresponding to an external quantum efficiency of 524% and a specific detectivity of 1.34 × 1012 Jones. Furthermore, the device manifests a short response/recovery time of ≈2/1 ms. Proof‐of‐concept broadband imaging as well as fitness monitoring (respiratory rate & heart rate) have been realized. Profited from the scalable preparation, an array of Sb2Se3 photodetectors have been produced, exhibiting qualified device‐to‐device variation. On the whole, this study has depicted an attractive landscape for next‐generation integrated optoelectronics. [ABSTRACT FROM AUTHOR]

Summary Background Methods Results Conclusions Apart from direct portal pressure reduction, non‐selective beta‐blockers (NSBB) modulate inflammatory response, which could be beneficial in patients with acute decompensation (AD). We therefore aimed to evaluate the effect of NSBB on 28‐day mortality and markers of systemic inflammation in a propensity score‐matched (PSM) cohort of AD patients requiring intensive care unit (ICU) admission.Patients were recruited from registry of AD patients requiring ICU admission. Out of total 445 patients, 108 patients on NSBB before admission (NSBB use group) were PSM for age, gender, pre‐admission Child–Turcotte–Pugh score and history of previous decompensation to 108 patients not on NSBB (non‐NSBB use group) which served as the control group. ICU parameters, markers of systemic inflammation and 28‐day mortality were compared by standard statistical tests.After PSM, no difference was observed in aetiology of cirrhosis, or precipitating event for AD between the groups. Pre‐admission creatinine, bilirubin, international normalised ratio and haemoglobin were similar between the groups, whereas pre‐admission white cell count (WCC) and neutrophil to lymphocyte ratio (NLR) was lower in NSBB‐group. On admission to ICU, NSBB group had lower heart rate (p = 0.006), platelets (p = 0.012), WCC (p = 0.006), NLR (p = 0.039) and C‐reactive protein (p = 0.007). Significantly more community acquired bacterial infections (p = 0.006), renal failure (p = 0.033) and higher grades of acute‐on‐chronic liver failure (ACLF; p = 0.012) were observed in non‐NSBB group. Significantly lower 28‐day (p = 0.001) and 90‐day (p = 0.002) mortality was seen in NSBB group. Univariate and multivariable analysis for 28‐day mortality showed that while ACLF at presentation and community acquired bacterial infection were independent negative predictors, prior NSBB use was positive predictors of survival.Prior use of NSBB is associated with improved 28‐ and 90‐day mortality in critically ill cirrhosis patients with AD which is mediated probably by blunting of the inflammatory response. [ABSTRACT FROM AUTHOR]

The aortic valve (AV) is crucial for cardiovascular (CV) hemodynamic, impacting cardiac output (CO) and left ventricular volumetric flow rate (LVQ). Its nonlinear behavior challenges standard LVQ prediction methods as well as CO one. This study presents a novel approach for modeling the AV in the CV system, offering an improved method for estimating crucial parameters like LVQ across various AV conditions, including aortic stenosis (AS). The model, based on AV channel length during the entire cardiac phase, introduces a time‐varying AV resistance (TV‐AVR) parameterized by the pressure ratio across the AV and LVQ, enabling the simulation of both healthy and AS‐related conditions. To validate this model, in vitro measurements are compared using a hybrid mock circulatory loop device. An unconventional use of a convolutional neural network (CNN) corrects the model's estimates, eliminating the need for labeled datasets. This approach, incorporating real‐time learning and transforming 1‐D CV signals into 2‐D tensors, significantly improves the accuracy of LVQ measurements, achieving an error rate of less than 3.41 ± 4.84% for CO in healthy conditions and 2.83 ± 1.35% in AS cases—a 33.13% enhancement over linear diode models. These results underscore the potential of this approach for enhancing the diagnosis, prediction, and treatment of AV diseases. The key contributions of the proposed method encompass nonlinear TV‐AVR estimation, investigation of transient CV responses, prediction of instantaneous CO, development of a flexible framework for noninvasive measurements integration, and the introduction of an adjustable resistance model using an extended Kalman filter (EKF) and CNN combination, all without requiring labeled data. [ABSTRACT FROM AUTHOR]

We propose a novel approach for predicting stress severity by measuring sleep phasic heart rate variability (HRV) using a smart device. This device can potentially be applied for stress self‐screening in large populations. Using a Holter electrocardiogram (ECG) and a Huawei smart device, we conducted 24‐h dual recordings of 159 medical workers working regular shifts. Based on photoplethysmography (PPG) and accelerometer signals acquired by the Huawei smart device, we sorted episodes of cyclic alternating pattern (CAP; unstable sleep), non‐cyclic alternating pattern (NCAP; stable sleep), wakefulness, and rapid eye movement (REM) sleep based on cardiopulmonary coupling (CPC) algorithms. We further calculated the HRV indices during NCAP, CAP and REM sleep episodes using both the Holter ECG and smart‐device PPG signals. We later developed a machine learning model to predict stress severity based only on the smart device data obtained from the participants along with a clinical evaluation of emotion and stress conditions. Sleep phasic HRV indices predict individual stress severity with better performance in CAP or REM sleep than in NCAP. Using the smart device data only, the optimal machine learning‐based stress prediction model exhibited accuracy of 80.3 %, sensitivity 87.2 %, and 63.9 % for specificity. Sleep phasic heart rate variability can be accurately evaluated using a smart device and subsequently can be used for stress predication. [ABSTRACT FROM AUTHOR]

Controllability beliefs and goodness beliefs about emotion are two fundamental emotion beliefs. The present study considered both controllability beliefs and goodness beliefs to examine whether and how the emotion beliefs of adolescents influence their test anxiety. Besides self‐reported test anxiety (sr‐TA), the present study measured heart rate (HR) and galvanic skin response (GSR) using custom‐designed wristbands during an exam as indicators of state test anxiety. The GSR was further decomposed into the tonic skin conductance level and the transient skin conductance response. The results revealed that, after controlling the goodness beliefs about anxiety, the controllability beliefs about emotion were negatively related to sr‐TA. This relationship was mediated by suppression. The controllability beliefs about emotion were directly related to the integration of transient skin conductance responses of 5 min before the exam. They were also indirectly related to the integration of transient skin conductance responses of the exam period, whether including the 5 min before the exam or not, and HR during certain periods through suppression. Therefore, adolescents' controllability beliefs about emotion may have important implications for their test anxiety. [ABSTRACT FROM AUTHOR]

Various reviews and meta‐analyses have shown the positive effects of mindfulness‐based interventions (MBIs) on the mental health of cancer patients and survivors. Some studies have also investigated the impact of MBIs on physiological markers of health in oncology, but a systematic review has not been conducted in this field. The current paper aims to fill this gap in the literature. Following preferred reporting items for systematic reviews and meta‐analyses 2020 guidelines, data were obtained from the databases of Pubmed, Scopus, Web of Science in May 2022. Twenty‐five studies were included. Globally, 35 biomarkers were employed in these studies and were categorized 8 groups (cortisol; blood pressure (BP), heart rate, and respiratory rate; C‐reactive protein; telomere length and telomerase activity (TA); genetic signature; cytokines and hormones; leucocyte activation; leucocyte count and cell subpopulation analysis). In seven of these categories of biomarkers, positive effects of MBIs were observed. The most promising results were obtained for cortisol, BP, TA and pro‐inflammatory gene expression. However, the generally low number of studies per single biomarker limits the possibility to draw reliable conclusions. The present review presents a comprehensive state‐of‐the‐art for MBIs in oncology on biomarkers, confirming MBIs' potential for improving physiological health in cancer patients and survivors besides those already shown in literature on psychological well‐being. [ABSTRACT FROM AUTHOR]

Stressful events are inherently emotional. As a result, the ability to regulate emotions is critical in responding effectively to stressors. Differential abilities in the management of stress appear very early in life, compelling a need to better understand factors that may shape the capacity for emotion regulation (ER). Variations in both biologic and behavioural characteristics are thought to influence individual differences in ER development. We sought to determine the differential contributions of temperament and heart rate variability (HRV; an indicator of autonomic nervous system function) to infant resting state emotionality and emotional reactivity in response to a stressor at 6 months of age. Participants included 108 mother‐infant dyads. Mothers completed a measure of infant temperament at 6 months postnatal. Mother and infant also participated in a standardized stressor (the Repeated Still Face Paradigm) at that time. Electrocardiographic data were acquired from the infant during a baseline resting state and throughout the stressor. Fast Fourier Transformation was used to analyse the high frequency (HF) domain of HRV, a measure of parasympathetic nervous system activity. Infant ER was measured via standardized coding of emotional distress behaviours from video‐records at baseline and throughout the stressor. Severity of mothers' depressive symptoms was included as a covariate in analyses. Results of linear regression indicate that neither temperament nor HRV were associated significantly with an infant's emotional resting state, although a small effect size was found for the relationship between infant negative affectivity and greater emotional distress (β = 0.23, p = 0.08) prior to the stressor. Higher HF‐HRV (suggesting parasympathetic dominance) was related to greater emotional distress in response to the stressor (β = 0.34, p = 0.009). This greater emotional reactivity may reflect a more robust capacity to mount an emotional response to the stressor when infants encounter it from a bedrock of parasympathetic activation. Findings may inform eventual markers for assessment of ER in infancy and areas for intervention to enhance infant management of emotions, especially during stressful events. [ABSTRACT FROM AUTHOR]

People experiencing homelessness report increased exposure to traumatic life events and higher rates of depression, anxiety, and post‐traumatic stress disorder as compared with the general population. Heart rate variability‐biofeedback (HRV‐BF) has been shown to decrease symptoms of stress, anxiety, depression, and PTSD. However, HRV‐BF has not been tested with the most vulnerable of populations, homeless adults. The purpose of this randomized controlled trial was to compare the effectiveness of an HRV‐BF intervention versus a Health Promotion (HP) active control intervention focused on improving mental health symptoms among homeless adults. Guided by a community advisory board, homeless adults residing in Skid Row, Los Angeles (n = 40) were randomized to either the HRV‐BF or an active HP control group and received eight weekly, 30‐min sessions over two months, delivered by a nurse‐led community health worker team. Dependent variables of HRV, mental health, anxiety, depression, and PTSD were measured at baseline, the 8‐week session, and/or 2‐month follow‐up. All intervention sessions were completed by 90% (36/40) of participants. Both the HRV‐BF and HP interventions showed significant increases in HRV from baseline to 2‐month follow‐up, with no significant difference between the intervention groups. The HRV‐BF programme revealed a somewhat greater, although non‐significant, improvement in anxiety, depression, and PTSD symptoms than the HP programme. The usefulness of both interventions, focused on emotional and physical health, warrants future studies to examine the value of a combined HRV‐BF and HP intervention. [ABSTRACT FROM AUTHOR]

Higher self‐reported rumination, a common form of trait perseverative cognition, is linked with lower resting heart rate variability (HRV), which indicates poorer cardiac function and greater disease risk. A meta‐analysis and systematic review indicated that in samples with fewer European Americans, the association of rumination with both heart rate and blood pressure was stronger. Thus, trait rumination may be more strongly associated with resting HRV among ethnically minoritized populations. The current study investigated whether differences in the association of self‐reported rumination with resting HRV varied by ethnicity in a sample (N = 513; Mage = 19.41; 226 Women) of self‐identified African Americans (n = 110), Asian Americans (n = 84), and European Americans (n = 319). Participants completed a five‐minute baseline period to assess resting HRV, followed by the Ruminative Responses Scale, which contains three facets of rumination including brooding, depressive, and reflective rumination. On average, Asian Americans reported higher levels of rumination relative to European Americans. African Americans had higher resting HRV than Asian Americans. Adjusting for covariates, higher self‐reported rumination was significantly associated with lower resting HRV in both African and Asian Americans, but not significantly so in European Americans. This finding was consistent for brooding and reflective, but not depressive rumination. Overall, this study lends insight into a psychological mechanism—rumination—that may impact health disparities among ethnically minoritized individuals, contributing to an understanding of how stress gets under the skin among such minoritized populations. [ABSTRACT FROM AUTHOR]

We investigated how apparent threat of an ambiguous stimuli modulates infants' looking to interaction partners of varying familiarity (mother, familiar experimenter, unfamiliar experimenter). We hypothesized a preference for familiar informants under higher apparent threat, but a preference for unfamiliar informants under lower apparent threat. The informant encouraged infants (N = 104, 8–13 months) to cross a visual cliff in one of two apparent threat conditions (lower vs. higher drop‐off). Under lower threat, infants looked equally long to all informants, but switched gazes more often between their mother and the cliff. Infants explored the cliff more and crossed more often in the mother condition compared to the other two conditions. They also expressed less negative affect in the presence of the mother compared to the unfamiliar experimenter, but not compared to the familiar experimenter. Under high threat, a similar pattern emerged, except that looking duration to the unfamiliar informant was shorter compared to the low threat condition. Heart rate acceleration appeared when infants were placed on the cliff compared to a baseline phase. Higher levels of negative affectivity (but not higher arousal) were observed under higher compared to lower threat. Overall, we found little evidence of the influence of threat within the visual cliff task. We argue that infants may have perceived the cliff as quite challenging even in the lower threat condition and call for more research on the situational embeddedness of early social learning processes. [ABSTRACT FROM AUTHOR]

Objective: The measurement and recording of vital signs may be impacted by biases, including preferences for even and round numbers. However, other biases, such as variation due to defined numerical boundaries (also known as boundary effects), may be present in vital signs data and have not yet been investigated in a medical setting. We aimed to assess vital signs data for such biases. These parameters are clinically significant as they influence care escalation. Methods: Vital signs data (heart rate, respiratory rate, oxygen saturation and systolic blood pressure) were collected from a tertiary hospital electronic medical record over a 2‐year period. These data were analysed using polynomial regression with additional terms to assess for underreporting of out‐of‐range observations and overreporting numbers with terminal digits of 0 (round numbers), 2 (even numbers) and 5. Results: It was found that heart rate, oxygen saturation and systolic blood pressure demonstrated 'boundary effects', with values inside the 'normal' range disproportionately more likely to be recorded. Even number bias was observed in systolic heart rate, respiratory rate and blood pressure. Preference for multiples of 5 was observed for heart rate and blood pressure. Independent overrepresentation of multiples of 10 was demonstrated in heart rate data. Conclusion: Although often considered objective, vital signs data are affected by bias. These biases may impact the care patients receive. Additionally, it may have implications for creating and training machine learning models that utilise vital signs data. [ABSTRACT FROM AUTHOR]

Purpose: The primary aims of this study were to examine the effects of 9 weeks of aerobic training, comprising three 30‐min sessions per week, on V̇O2max, inhibitory control, and plasma brain‐derived neurotrophic factor (BDNF) levels among adolescents aged 16–19 years. Methods: One hundred twenty‐one untrained or recreationally active adolescents from a Danish high school were enrolled in the study, with 58 females (17.8 ± 0.8 years) and 27 males (18.0 ± 0.9 years) completing it. Participants were randomly divided into three groups performing aerobic training at either moderate‐intensity (MIT: 60%–70% heart rate reserve [HRR]) or high‐intensity (HIT: 80%–100% HRR) or a passive control group (CON) continuing their habitual lifestyle. Both the training groups exercised for 3×30 min per week for 9 weeks using a combination of cycling and running. Before and after the intervention period maximal oxygen uptake (V̇O2max) and the primary outcomes (inhibitory control measured by a modified flanker task, and resting plasma levels of BDNF) were evaluated. Results: After the intervention period, the HIT group demonstrated a larger increase in V̇O2max compared to both the CON and MIT groups, while no significant effects were observed on inhibitory control or plasma BDNF levels in any training group. However, compared to the CON group, the HIT group exhibited a tendency for greater improvement in the flanker interference score (accuracy), attributable to enhanced accuracy on the incongruent stimuli from pre to post. Conclusion: Aerobic training in adolescents increased cardiorespiratory fitness in an intensity‐dependent manner, but no clear effects were observed on neither inhibitory control nor resting plasma BDNF levels. Clinical Trial Registration: ClinicalTrials.gov: NCT02075944. [ABSTRACT FROM AUTHOR]

This study aimed to compare performance, kinematic, and physiological variables between open water and pool swimming conditions in elite triathletes and to examine the associations between conditions on these variables. Fourteen elite triathletes (10 males and 4 females [23.4 ± 3.8 years]) performed two 1500‐m swimming tests in open water and in a 25‐m pool. Swimming speed, stroke rate (SR), length (SL) and index (SI), heart rate (HR), blood lactate concentrations [La−], and end‐exercise oxygen uptake (EEV̇O2) were assessed in both conditions. Lower SL and SI and higher SR were obtained in open water compared with pool swimming (p < 0.05). Moreover, kinematic variables changed as a function of distance in both conditions (p < 0.05). No differences were found in the main physiological variables (HR, [La−], and EEV̇O2) between conditions. Respiratory exchange ratio presented lower values in open water than in pool conditions (p < 0.05), while time constant was higher in open water (p = 0.032). The fastest triathletes in open water obtained the best performance in the pool (r = 0.958; p < 0.001). All kinematic variables, HR and peak [La−] presented positive associations between conditions (r > 0.6; p < 0.05). Despite physiological invariance, triathletes and coaches should monitor specific open water training to adapt their swimming technique to the competitive environment. [ABSTRACT FROM AUTHOR]

Intense interval exercise training has been shown to improve performance and health of untrained and trained people. However, due to the exercise intensity causing high‐perceived exertion, the participants often do not wish to continue the training. The 10‐20‐30 training concept consists of low intensity for 30 s, 20 s at a moderate pace, and then 10 s with high intensity either running or cycling. A 10‐20‐30 training session consist of two to four 5‐min blocks. The 10‐20‐30 training improved fitness and performance as well as lowered blood pressure and body fat of both untrained and trained individuals even with a significant reduction in the training volume. Similarly, hypertensive, diabetic, and asthmatic patients lowered body fat, improved fitness, and performance during a 10‐20‐30‐training intervention period. In addition, hypertensive patients reduced systolic and diastolic blood pressure markedly with the 10‐20‐30 training twice a week for 8 weeks. Diabetic patients lowered long‐term blood sugar (HbA1c), which did not occur with moderate‐intensity exercise training. Furthermore, asthmatic patients improved their control of asthma and asthma‐related quality of life with the 10‐20‐30 training. The adherence for the patient groups was high (>80%), and no adverse events were reported. Thus, the 10‐20‐30 training seems to be time efficient and feasible for untrained and trained individuals as well as patients and may be used in the prevention and treatment of noncommunicable diseases. Highlights: What is already known? Aerobic moderate‐intensity exercise training has been shown to improve fitness and health of untrained individuals.Intense exercise training has been shown to benefit some patient groups, but many patients are struggling with the training due to the strenuous effort experienced during training.Untrained individuals and patients have difficulties to find time and motivation to do physical activities. What are the findings? The 10‐20‐30 training is a new training modality, which has greater benefits than aerobic moderate‐intensity training, and is a more time‐efficient way to improve performance and health even in trained people.The 10‐20‐30 training reduces blood pressure and body fat in untrained and already trained people even with lowered training volume.The 10‐20‐30 training is feasible for hypertensive, diabetic, and asthmatic patients, who with the 10‐20‐30 training are reducing blood pressure, improve long‐term blood sugar management, and lower symptoms of asthma, respectively. [ABSTRACT FROM AUTHOR]

Bouts of military load carriage are rarely completed in isolation; however, limited research has investigated the physiological responses to repeated load carriage tasks. Twelve civilian men (age, 28 ± 8 years; stature, 185.6 ± 5.8 cm; body mass 84.3 ± 11.1 kg and maximal oxygen uptake, 51.5 ± 6.4 mL·kg−1 min−1) attended the laboratory on two occasions to undertake a familiarisation and an experimental session. Following their familiarisation session, participants completed three bouts of a fast load carriage protocol (FLCP; ∼65 min), carrying 25 kg, interspersed with a 65‐min recovery period. Physiological strain (oxygen uptake [V̇O2] and heart rate [HR]) was assessed during the FLCP bouts, and physical performance assessments (weighted counter‐movement jump [wCMJ], maximal isometric voluntary contraction of the quadriceps [MIVC] and seated medicine ball throw [SMBT]) was measured pre and post each FLCP bout. A main effect for bout and measurement time was evident for V̇O2 and HR (both p < 0.001 and Ѡ2 = 0.103–0.816). There was no likely change in SMBT distance (p = 0.201 and Ѡ2 = 0.004), but MIVC peak force reduced by approximately 25% across measurement points (p < 0.001 and Ѡ2 = 0.133). A mean percentage change of approximately −12% from initial values was also evident for peak wCMJ height (p = 0.001 and Ѡ2 = 0.028). Collectively, these data demonstrate that repeated FLCP bouts result in an elevated physiological strain for each successive bout, along with a substantial reduction in lower body power (wCMJ and MIVC). Therefore, future research should investigate possible mitigation strategies to maintain role‐related capability. Highlights: Given the progressively greater internal work rate for each successive load carriage bout (of equal external work rate), individuals responsible for load carriage planning should factor this elevated work rate into their operational planning (e.g., estimated maximal work durations).Elevated work rate for successive bouts should also be considered in other domains such as physical employment standards and development of working patterns.Group level perceptual measures appear to provide a good indication of physiological strain and therefore may provide useful information to commanders regarding the physical strain experienced by their team. [ABSTRACT FROM AUTHOR]

We examine the impact of the acute manipulation of oxygen availability during discrete phases (active and passive) of a repeated‐sprint cycling protocol on performance, physiological, and perceptual responses. On separate days, twelve trained males completed four sets of five 5‐s 'all out' cycle sprints (25‐s inter‐sprint recovery and 5‐min interset rest) in four randomized conditions: normobaric hypoxia (inspired oxygen fraction of 12.9%) applied continuously (C‐HYP), intermittently during only the sets of sprints (I‐HYPSPRINT) or between‐sets recovery periods (I‐HYPRECOVERY), or not at all (C‐NOR). Peak and mean power output, peripheral oxygen saturation, heart rate, blood lactate concentration, exercise‐related sensations, and vastus lateralis muscle oxygenation using near‐infrared spectroscopy were assessed. Peak and mean power output was ∼4%–5% lower for C‐HYP compared to C‐NOR (P ≤ 0.050) and I‐HYPRECOVERY (P ≤ 0.027). Peripheral oxygen saturation was lower during C‐HYP and I‐HYPSPRINT compared with C‐NOR and I‐HYPRECOVERY during sets of sprints (∼83–85 vs. ∼95%–97%; P < 0.001), while lower values were obtained for C‐HYP and I‐HYPRECOVERY than C‐NOR and I‐HYPSPRINT during between‐sets rest period (∼84–85 vs. ∼96%; P < 0.001). Difficulty in breathing was ∼21% higher for C‐HYP than C‐NOR (P = 0.050). Ratings of perceived exertion (P = 0.435), limb discomfort (P = 0.416), heart rate (P = 0.605), blood lactate concentration (P = 0.976), and muscle oxygenation‐derived variables (P = 0.056 to 0.605) did not differ between conditions. In conclusion, the method of hypoxic exposure application (continuous vs. intermittent) affects mechanical performance, while internal demands remained essentially comparable during repeated cycle sprints. Highlights: Continuous hypoxic exposure resulted in reduced repeated sprint performance compared to both normoxia and intermittent hypoxia during recoveries.Cardiovascular solicitation and glycolytic contribution showed no significant differences between ambient air and hypoxic conditions regardless of the timing of hypoxic gas administration (entire session, sprints only, or recovery only).The method of applying hypoxic exposure significantly affected mechanical performance, while internal physiological demands remained essentially comparable between conditions during repeated cycle sprints. [ABSTRACT FROM AUTHOR]

Heart rate is a crucial vital sign and a valuable indicator for assessing the physical and psychological condition of a target animal. Heart rate contributes to (1) fundamental information for cognitive research, (2) an indicator of psychological and physical stress, and (3) improving the animal welfare of captive animals, especially in nonhuman primate studies. Heart rate has been measured using a contact‐type device; however, the device burdens the target animals and that there are risks associated with anesthesia during installation. This study explores the application of heartbeat measurement techniques using millimeter‐wave radar, primarily developed for humans, as a remote and noninvasive method for measuring the heart rate of nonhuman primates. Through a measurement test conducted on two chimpanzees, we observed a remarkable correspondence between the peak frequency spectrum of heart rate estimated using millimeter‐wave radar and the mean value obtained from electrocardiograph data, thereby validating the accuracy of the method. To the best of our knowledge, this is the first demonstration of the precise measurement of great apes' heart rate using millimeter‐wave radar technology. Compared to heart rate measurement using video analysis, the method using millimeter‐wave radar has the advantage that it is less susceptible to weather and lighting conditions and that measurement techniques for multiple individuals have been developed for human subjects, while its disadvantage is that validation of measurement from long distances has not been completed. Another disadvantage common to both methods is that measurement becomes difficult when the movement of the target individual is large. The possibility of noncontact measurement of heart rate in wild and captive primates will undoubtedly open up a new research area while taking animal welfare into consideration. Research Highlights: Applied millimeter‐wave radar measured chimpanzees heart rate accurately, marking the first use of this technology in great apes.Millimeter‐wave radar heart rate measurement holds promise for managing the health of endangered great apes. [ABSTRACT FROM AUTHOR]