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Dietary nitrate (NO 3 −) supplementation can increase nitric oxide (NO) bioavailability, reduce blood pressure (BP) and improve muscle contractile function in humans. Plasma nitrite concentration (plasma [NO 2 −]) is the most oft-used biomarker of NO bioavailability. However, it is unclear which of several NO biomarkers (NO 3 −, NO 2 −, S-nitrosothiols (RSNOs)) in plasma, whole blood (WB), red blood cells (RBC) and skeletal muscle correlate with the physiological effects of acute and chronic dietary NO 3 − supplementation. Using a randomized, double-blind, crossover design, 12 participants (9 males) consumed NO 3 −-rich beetroot juice (BR) (∼12.8 mmol NO 3 −) and NO 3 −-depleted placebo beetroot juice (PL) acutely and then chronically (for two weeks). Biological samples were collected, resting BP was assessed, and 10 maximal voluntary isometric contractions of the knee extensors were performed at 2.5–3.5 h following supplement ingestion on day 1 and day 14. Diastolic BP was significantly lower in BR (−2 ± 3 mmHg, P = 0.03) compared to PL following acute supplementation, while the absolute rate of torque development (RTD) was significantly greater in BR at 0–30 ms (39 ± 57 N m s−1, P = 0.03) and 0–50 ms (79 ± 99 N m s−1, P = 0.02) compared to PL following two weeks supplementation. Greater WB [RSNOs] rather than plasma [NO 2 −] was correlated with lower diastolic BP (r = −0.68, P = 0.02) in BR compared to PL following acute supplementation, while greater skeletal muscle [NO 3 −] was correlated with greater RTD at 0–30 ms (r = 0.64 , P= 0.03) in BR compared to PL following chronic supplementation. We conclude that [RSNOs] in blood, and [NO 3 −] in skeletal muscle, are relevant biomarkers of NO bioavailability which are related to the reduction of BP and the enhanced muscle contractile function following dietary NO 3 − ingestion in humans. • It is unclear which NO biomarkers in blood and muscle correlate with the physiological effects of acute and chronic dietary nitrate supplementation. • In a crossover design, participants consumed NO 3 −-rich beetroot juice (BR) and NO 3 −-depleted placebo (PL) acutely and then for two weeks. • Greater whole blood [RSNOs] was correlated with lower diastolic BP with BR, while greater skeletal muscle [NO 3 −] was correlated with greater rate of muscle torque development with BR. • RSNOs in blood, and NO 3 − in skeletal muscle, are relevant biomarkers of NO bioavailability which are related to the physiological effects of dietary NO 3 − ingestion in humans. [ABSTRACT FROM AUTHOR]

Dietary nitrate (NO 3 −) ingestion can be beneficial for health and exercise performance. Recently, based on animal and limited human studies, a skeletal muscle NO 3 − reservoir has been suggested to be important in whole body nitric oxide (NO) homeostasis. The purpose of this study was to determine the time course of changes in human skeletal muscle NO 3 − concentration ([NO 3 −]) following the ingestion of dietary NO 3 −. Sixteen participants were allocated to either an experimental group (NIT: n = 11) which consumed a bolus of ∼1300 mg (12.8 mmol) potassium nitrate (KNO 3), or a placebo group (PLA: n = 5) which consumed a bolus of potassium chloride (KCl). Biological samples (muscle (vastus lateralis), blood, saliva and urine) were collected shortly before NIT or PLA ingestion and at intervals over the course of the subsequent 24 h. At baseline, no differences were observed for muscle [NO 3 −] and [NO 2 −] between NIT and PLA (P > 0.05). In PLA, there were no changes in muscle [NO 3 −] or [NO 2 −] over time. In NIT, muscle [NO 3 −] was significantly elevated above baseline (54 ± 29 nmol/g) at 0.5 h, reached a peak at 3 h (181 ± 128 nmol/g), and was not different to baseline from 9 h onwards (P > 0.05). Muscle [NO 2 −] did not change significantly over time. Following ingestion of a bolus of dietary NO 3 −, skeletal muscle [NO 3 −] increases rapidly, reaches a peak at ∼3 h and subsequently declines towards baseline values. Following dietary NO 3 − ingestion, human m. vastus lateralis [NO 3 −] expressed a slightly delayed pharmacokinetic profile compared to plasma [NO 3 −]. • Nitrate in skeletal muscle may be important in whole-body nitric oxide homeostasis. • We measured changes in human muscle nitrate after dietary nitrate ingestion. • Muscle nitrate levels increase at 0.5 h, peak at 3 h and return to baseline by 9 h. • Muscle nitrate pharmacokinetics are broadly similar to those of plasma nitrate. [ABSTRACT FROM AUTHOR]

Dietary nitrate (NO 3 −) supplementation can enhance nitric oxide (NO) bioavailability and lower blood pressure (BP) in humans. The nitrite concentration ([NO 2 −]) in the plasma is the most commonly used biomarker of increased NO availability. However, it is unknown to what extent changes in other NO congeners, such as S-nitrosothiols (RSNOs), and in other blood components, such as red blood cells (RBC), also contribute to the BP lowering effects of dietary NO 3 −. We investigated the correlations between changes in NO biomarkers in different blood compartments and changes in BP variables following acute NO 3 − ingestion. Resting BP was measured and blood samples were collected at baseline, and at 1, 2, 3, 4 and 24 h following acute beetroot juice (∼12.8 mmol NO 3 −, ∼11 mg NO 3 −/kg) ingestion in 20 healthy volunteers. Spearman rank correlation coefficients were determined between the peak individual increases in NO biomarkers (NO 3 −, NO 2 −, RSNOs) in plasma, RBC and whole blood, and corresponding decreases in resting BP variables. No significant correlation was observed between increased plasma [NO 2 −] and reduced BP, but increased RBC [NO 2 −] was correlated with decreased systolic BP (r s = −0.50, P = 0.03). Notably, increased RBC [RSNOs] was significantly correlated with decreases in systolic (r s = −0.68, P = 0.001), diastolic (r s = −0.59, P = 0.008) and mean arterial pressure (r s = −0.64, P = 0.003). Fisher's z transformation indicated no difference in the strength of the correlations between increases in RBC [NO 2 −] or [RSNOs] and decreased systolic blood pressure. In conclusion, increased RBC [RSNOs] may be an important mediator of the reduction in resting BP observed following dietary NO 3 − supplementation. • Dietary nitrate (NO 3 −) supplementation elevates plasma nitrite concentration ([NO 2 −]) and can lower blood pressure (BP) in humans. • We investigated the correlations between changes in relevant NO congeners in different blood compartments and corresponding changes in BP variables following acute NO 3 − ingestion. • There was no significant correlation between increased plasma [NO 2 −] and reduced BP, but increased red blood cell [NO 2 −] was correlated with decreased systolic BP. • Notably, increased red blood cell S-nitrosothiol concentration ([RSNOs]) was significantly correlated with decreases in systolic, diastolic and mean arterial pressure. • Red blood cell [RSNOs] may be an important mediator of the reduction in resting BP observed following dietary NO 3 − supplementation in humans. [ABSTRACT FROM AUTHOR]

Abstract: In human–human interactions, entrainment is a naturally occurring phenomenon that happens when interlocutors mutually adapt their behaviors through the course of an interaction. This mutual behavioral dependency has been at the center of psychological studies of human communication for decades. Quantitative descriptors of the degree of entrainment can provide psychologists an objective method to advance studies of human communication including in mental health domains. However, the subtle nature of the entrainment phenomenon makes it challenging for computing such an effect based on just human annotations. In this paper, we propose an unsupervised signal-derived approach within a principal component analysis framework for quantifying one aspect of entrainment in communication, namely, vocal entrainment. The proposed approach to quantify the degree of vocal entrainment involves measuring the similarity of specific vocal characteristics between the interlocutors in a dialog. These quantitative descriptors were analyzed using two psychology-inspired hypothesis tests to not only establish that these signal-derived measures carry meaningful information in interpersonal communication but also offer statistical evidence into aspects of behavioral dependency and associated affective states in marital conflictual interactions. Finally, affect recognition experiments were performed with the proposed vocal entrainment descriptors as features using a large database of real distressed married couples’ interactions. An accuracy of 62.56% in differentiating between positive and negative affect was obtained using these entrainment measures with Factorial Hidden Markov Models lending further support that entrainment is an active component underlying affective processes in interactions. [Copyright &y& Elsevier]

Abstract: Segmental and suprasegmental speech signal modulations offer information about paralinguistic content such as affect, age and gender, pathology, and speaker state. Speaker state encompasses medium-term, temporary physiological phenomena influenced by internal or external bio-chemical actions (e.g., sleepiness, alcohol intoxication). Perceptual and computational research indicates that detecting speaker state from speech is a challenging task. In this paper, we present a system constructed with multiple representations of prosodic and spectral features that provided the best result at the Intoxication Subchallenge of Interspeech 2011 on the Alcohol Language Corpus. We discuss the details of each classifier and show that fusion improves performance. We additionally address the question of how best to construct a speaker state detection system in terms of robust and practical marginalization of associated variability such as through modeling speakers, utterance type, gender, and utterance length. As is the case in human perception, speaker normalization provides significant improvements to our system. We show that a held-out set of baseline (sober) data can be used to achieve comparable gains to other speaker normalization techniques. Our fused frame-level statistic-functional systems, fused GMM systems, and final combined system achieve unweighted average recalls (UARs) of 69.7%, 65.1%, and 68.8%, respectively, on the test set. More consistent numbers compared to development set results occur with matched-prompt training, where the UARs are 70.4%, 66.2%, and 71.4%, respectively. The combined system improves over the Challenge baseline by 5.5% absolute (8.4% relative), also improving upon our previously best result. [Copyright &y& Elsevier]