Estimating and approaching the maximum information rate of noninvasive visual brain-computer interface.

An essential priority of visual brain-computer interfaces (BCIs) is to enhance the information transfer rate (ITR) to achieve high-speed communication. Despite notable progress, noninvasive visual BCIs have encountered a plateau in ITRs, leaving it uncertain whether higher ITRs are achievable. In this study, we used information theory to study the characteristics and capacity of the visual-evoked channel, which leads us to investigate whether and how we can decode higher information rates in a visual BCI system. Using information theory, we estimate the upper and lower bounds of the information rate with the white noise (WN) stimulus. Consequently, we found out that the information rate is determined by the signal-to-noise ratio (SNR) in the frequency domain, which reflects the spectrum resources of the channel. Based on this discovery, we propose a broadband WN BCI by implementing stimuli on a broader frequency band than the steady-state visual evoked potentials (SSVEPs)-based BCI. Through validation, the broadband BCI outperforms the SSVEP BCI by an impressive 7 bps, setting a record of 50 bps. The integration of information theory and the decoding analysis presented in this study offers valuable insights applicable to general sensory-evoked BCIs, providing a potential direction of next-generation human-machine interaction systems.

Effects of nitric oxide inhalation on pulmonary arterial impedance: differences between normal and pulmonary hypertension male rats.

Nitric oxide (NO) inhalation improves pulmonary hemodynamics in participants with pulmonary arterial hypertension (PAH). Although it can reduce pulmonary vascular resistance (PVR) in PAH, its impact on the dynamic mechanics of pulmonary arteries and its potential difference between control and participants with PAH remain unclear. PA impedance provides a comprehensive description of PA mechanics. With an arterial model, PA impedance can be parameterized into peripheral pulmonary resistance (Rp), arterial compliance (Cp), characteristic impedance of the proximal arteries (Zc), and transmission time from the main PA to the reflection site. This study investigated the effects of inhaled NO on PA impedance and its associated parameters in control and monocrotaline-induced pulmonary arterial hypertension (MCT-PAH) male rats (6/group). Measurements were obtained at baseline and during NO inhalation at 40 and 80 ppm. In both groups, NO inhalation decreased PVR and increased the left atrial pressure. Notably, its impact on PA impedance was frequency dependent, as revealed by reduced PA impedance modulus in the low-frequency range below 10 Hz, with little effect on the high-frequency range. Furthermore, NO inhalation attenuated Rp, increased Cp, and prolonged transmission time without affecting Zc. It reduced Rp more pronouncedly in MCT-PAH rats, whereas it increased Cp and delayed transmission time more effectively in control rats. In conclusion, the therapeutic effects of inhaled NO on PA impedance were frequency dependent and may differ between the control and MCT-PAH groups, suggesting that the effect on the mechanics differs depending on the pathological state.NEW & NOTEWORTHY Nitric oxide inhalation decreased pulmonary arterial impedance in the low-frequency range (<10 Hz) with little impact on the high-frequency range. It reduced peripheral pulmonary resistance more pronouncedly in pulmonary hypertension rats, whereas it increased arterial compliance and transmission time in control rats. Its effect on the mechanics of the pulmonary arteries may differ depending on the pathological status.

Short-term dynamic characteristics of diuresis during exogenous pressure perturbations with and without arterial baroreflex control.

Although body fluid volume control by the kidneys may be classified as a long-term arterial pressure (AP) control system, it does not necessarily follow that the urine flow (UF) response to changes in AP is slow. We quantified the dynamic characteristics of the UF response to short-term AP changes by changing mean AP between 60 mmHg and 100 mmHg every 10 s according to a binary white noise sequence in anesthetized rats (n = 8 animals). In a baro-on trial (the carotid sinus baroreflex was enabled), the UF response represented the combined synergistic effects of pressure diuresis (PD) and neurally mediated antidiuresis (NMA). In a baro-fix trial (the carotid sinus pressure was fixed at 100 mmHg), the UF response mainly reflected the effect of PD. The UF step response was quantified using the sum of two exponential decay functions. The fast and slow components had time constants of 6.5 ± 3.6 s and 102 ± 85 s (means ± SD), respectively, in the baro-on trial. Although the gain of the fast component did not differ between the two trials (0.49 ± 0.21 vs. 0.66 ± 0.22 µL·min-1·kg-1·mmHg-1), the gain of the slow component was greater in the baro-on than in the baro-fix trial (0.51 ± 0.14 vs. 0.09 ± 0.39 µL·min-1·kg-1·mmHg-1, P = 0.023). The magnitude of NMA relative to PD was calculated to be 32.2 ± 29.8%. In conclusion, NMA contributed to the slow component, and its magnitude was approximately one-third of that of the effect of PD.NEW & NOTEWORTHY We quantified short-term dynamic characteristics of the urine flow (UF) response to arterial pressure (AP) changes using white noise analysis. The UF step response approximated the sum of two exponential decay functions with time constants of ∼6.5 s and 102 s. The neurally mediated antidiuretic (NMA) effect contributed to the slow component of the UF step response, with the magnitude of approximately one-third of that of the pressure diuresis (PD) effect.

Nutrient enrichment and phytoplankton toxicity influence a diversity of complex dynamics in a fear-induced plankton-fish model.

In this paper, we contemplate the dynamics of an aquatic system consisting of three interacting species, phytoplankton, zooplankton, and fish. We assume that the evading risk of fish predation induces fear in zooplankton species, which affects its growth dynamics radically. On the other hand, zooplankton develop an anti-predator defense by taking temporary refuge. Interestingly, the system potentially exhibits multi-stable configurations under identical ecological conditions by allowing different bifurcation scenarios, including multiple saddle-node and transcritical bifurcations with varying levels of nutrients, strength of phytoplankton toxicity, zooplankton refuge size and the cost of fear imposed by fish population. Further, by adding Gaussian white noise, we have extended the deterministic system to its stochastic version. We find that white noise appears to regulate the survival and extinction of model species. Comprehensive numerical simulations are consistent with mathematical results prognosticated by linear analysis. Overall, our study may provide a new insight into the mechanisms of emergence and mitigation of plankton blooms.

Effect of kangaroo mother care and white noise on physiological-stress parameters in heel lancing: randomized controlled study.

BACKGROUND: Newborns are exposed to varying degrees of stressful interventions due to procedures such as heel lancing used in routine metabolic screenings. It is an examination of the effects of white noise and kangaroo care on some physiological parameters and stress markers (cortisol and glucose-regulated protein 78-GRP78) in heel lancing in newborns. METHODS: Randomized controlled study was conducted at a gynecology service of a hospital between January and September 2023. 90 babies were divided into three groups: 30 babies in the Kangaroo Care Group (KCG), 30 babies in the White Music Group (WMG), and 30 babies in the Control Group (CG). All babies were randomly divided into groups. Stress parameters were measured by saliva collection method and physiological parameters by saturation device. RESULTS: A statistically significant difference was determined between the total crying time, pulse and saturation values ​​according to the groups (p < 0.001; p = 0.001). A statistically significant difference was determined between the mean values ​​of cortisol and GRP78 measurements according to group and time interaction (p < 0.001). KCG was more effective in reducing total crying time and stabilizing pulse, saturation, salivary cortisol, GRP-78 values compared to WNG and CG. CONCLUSION: It was concluded that white noise and kangaroo care help reduce newborns' stress in the case of heel lancing. PRACTICAL IMPLICATIONS: The practice of kangaroo care and the use of white noise methods may assist healthcare professionals as supportive methods in stress management during invasive procedures. TRIAL REGISTRATION: NCT06278441, registered on 19/02/2024.

Effect of white noise during nasal continuous positive airway pressure application on newborn's pain and stress levels, physiological parameters, and crying durations: A randomized controlled study.

PURPOSE: The study was conducted to determine the effects of white noise during nasal continuous positive airway pressure (CPAP) application on the newborn's pain and stress levels, physiological parameters, and crying durations. DESIGN AND METHODS: The study used a randomized, controlled experimental design. The study was completed with 80 newborns (40 in the intervention group and 40 in the control group). The Newborn Descriptive Data Form, ALPS Newborn Pain and Stress Assessment Scale, and Follow-up Form were used to collect the study data. Routine nasal CPAP application was performed to newborns in the control group. White noise was played to newborns in the intervention group before, during, and after the nasal CPAP application. The study was approved by an ethics committee. RESULTS: It was found that the newborn's pain and stress levels of the intervention group were lower than the control group before, during, and after the nasal CPAP application (p < 0.05). Before nasal CPAP application, the intervention group's SpO2 average was lower than that of the control group (p < 0.01). During nasal CPAP application, the intervention group's heart rate, SpO2, and crying duration averages were found to be lower than the control group (p < 0.05). After nasal CPAP application, the intervention group's crying duration average was lower than the control group (p < 0.01). CONCLUSIONS: It was found that white noise before, during, and after the nasal CPAP application reduced newborns' pain and stress levels. PRACTICE IMPLICATION: It is recommended that white noise be used as an easily applicable, economical, safe, and non-pharmacological method to reduce the pain and stress caused by nasal CPAP application in newborns. CLINICAL TRIALS REGISTRATION: The study was registered at Clinical-Trials.gov (NCT05440669).

The effect of facilitated tucking and white noise on stress and sleep of newborns receiving nasal continuous positive airway pressure.

OBJECTIVE: To investigate the effects of facilitated tucking and white noise on stress and sleep in neonates receiving nasal continuous positive airway pressure (CPAP). METHOD: This study was conducted as a randomised controlled experimental study of neonates receiving nasal CPAP in neonatal intensive care units. The study sample consisted of 108 newborns (facilitated tucking (n = 36), white noise (n = 36) and control (n = 36)) receiving nasal CPAP support in the NICU. The neonates' sleep parameters were recorded by actigraphy for 24 h. Data were collected using the Neonatal Descriptive Information Form, the Sleep Tracking Form and the Neonatal Stress Scale. Percentage, mean, chi-squared and one-way ANOVA were used for data analysis. RESULTS: It was found that 50.9% of the newborns were female, their mean gestational age was 33.54 ± 3.38, their mean height was 43.56 ± 5.12, and their mean weight was 2139.23 ± 827.82. The total sleep time of the neonates in the facilitated tucking and white noise group increased by 3 h, their sleep efficiency increased by 20% and their mean stress scores decreased (p < 0.05). CONCLUSION: Facilitated tucking and white noise each showed a similar improvement in sleep duration and sleep efficiency and a reduction in stress scores in neonates receiving nasal CPAP. Close monitoring of sleep in this population and supportive care practices are recommended. PRACTICE IMPLICATIONS: The findings of this study may help to reduce sleep problems and stress levels in the clinical care of neonates in the NICU through developmental nursing practices.

The effects of white noise and swaddling methods on orogastric tube insertion-related pain in preterm infants: A randomized controlled trial.

AIM: This study aims to investigate the effects of the white noise, swaddling and white noise + swaddling methods on pain and physiological parameters associated with orogastric tube insertion procedure. METHODS: This was a randomized controlled trial. A total of 132 preterm infants were randomly assigned to four groups as white noise group (n = 33), swaddling group (n = 33), white noise + swaddling group (n = 33) and control group (n = 33). Interventions were initiated 5 min before the orogastric tube insertion procedure and continued during and up to 5 min after the procedure. RESULTS: White noise intervention alone did not have a significant effect on reducing pain associated with orogastric tube insertion (p > 0.05). Compared with the control group, the preterm infants in the swaddling group experienced 0.587 times less pain, and those in the white noise + swaddling group experienced 0.473 times less pain. CONCLUSIONS: Findings indicate the swaddling and the combination of white noise + swaddling may be a useful intervention in reducing the invasive pain experienced by preterm infants during and after orogastric tube insertion and in improving the physiological parameters associated with pain.

Effectiveness of virtual reality glasses versus white noise on dental anxiety in children with attention-deficit hyperactivity disorder: A randomised controlled clinical trial.

BACKGROUND: Management of children with attention-deficit hyperactivity disorder (ADHD) can be challenging due to their disruptive behaviour. Basic behaviour management techniques (BMTs) may not be sufficient, and adjunctive strategies such as virtual reality (VR) glasses or white noise can be employed. AIM: To assess and compare the effectiveness of VR, white noise and basic BMTs on dental anxiety and behaviour of children with ADHD. DESIGN: Forty-eight children with ADHD were recruited for this parallel, three-armed randomised controlled clinical trial, which involved three visits at one-week intervals, including examination, preventive measures and restorations. Children were randomly divided into three groups: VR, white noise and basic BMTs. Outcome measures were Faces Image Scale (FIS), Heart Rate (HR) and Venham's Behaviour Rating Scale (VBRS). RESULTS: No significant difference was found between the groups in FIS scores. White noise group had a significantly lower mean HR than control group in all visits. Scores of VBRS in VR and white noise groups were significantly lower than those in the control group during the restorative visit. CONCLUSIONS: VR and white noise could be beneficial in managing dental anxiety and improving behaviour in children with ADHD and could be used as adjunctive strategies to basic BMTs.

Perceptual Weighting of V1 Spikes Revealed by Optogenetic White Noise Stimulation.

During visually guided behaviors, mere hundreds of milliseconds can elapse between a sensory input and its associated behavioral response. How spikes occurring at different times are integrated to drive perception and action remains poorly understood. We delivered random trains of optogenetic stimulation (white noise) to excite inhibitory interneurons in V1 of mice of both sexes while they performed a visual detection task. We then performed a reverse correlation analysis on the optogenetic stimuli to generate a neuronal-behavioral kernel, an unbiased, temporally precise estimate of how suppression of V1 spiking at different moments around the onset of a visual stimulus affects detection of that stimulus. Electrophysiological recordings enabled us to capture the effects of optogenetic stimuli on V1 responsivity and revealed that the earliest stimulus-evoked spikes are preferentially weighted for guiding behavior. These data demonstrate that white noise optogenetic stimulation is a powerful tool for understanding how patterns of spiking in neuronal populations are decoded in generating perception and action.SIGNIFICANCE STATEMENT During visually guided actions, continuous chains of neurons connect our retinas to our motoneurons. To unravel circuit contributions to behavior, it is crucial to establish the relative functional position(s) that different neural structures occupy in processing and relaying the signals that support rapid, precise responses. To address this question, we randomly inhibited activity in mouse V1 throughout the stimulus-response cycle while the animals did many repetitions of a visual task. The period that led to impaired performance corresponded to the earliest stimulus-driven response in V1, with no effect of inhibition immediately before or during late stages of the stimulus-driven response. This approach offers experimenters a powerful method for uncovering the temporal weighting of spikes from stimulus to response.

Walking bumblebees see faster.

The behavioural state of animals has profound effects on neuronal information processing. Locomotion changes the response properties of visual interneurons in the insect brain, but it is still unknown if it also alters the response properties of photoreceptors. Photoreceptor responses become faster at higher temperatures. It has therefore been suggested that thermoregulation in insects could improve temporal resolution in vision, but direct evidence for this idea has so far been missing. Here, we compared electroretinograms from the compound eyes of tethered bumblebees that were either sitting or walking on an air-supported ball. We found that the visual processing speed strongly increased when the bumblebees were walking. By monitoring the eye temperature during recording, we saw that the increase in response speed was in synchrony with a rise in eye temperature. By artificially heating the head, we show that the walking-induced temperature increase of the visual system is sufficient to explain the rise in processing speed. We also show that walking accelerates the visual system to the equivalent of a 14-fold increase in light intensity. We conclude that the walking-induced rise in temperature accelerates the processing of visual information-an ideal strategy to process the increased information flow during locomotion.

Dynamic accentuated antagonism of heart rate control during different levels of vagal nerve stimulation intensity in rats.

Accentuated antagonism refers to a phenomenon in which the vagal effect on heart rate (HR) is augmented by background sympathetic tone. The dynamic aspect of accentuated antagonism remains to be elucidated during different levels of vagal nerve stimulation (VNS) intensity. We performed VNS on anesthetized rats (n = 8) according to a binary white noise signal with a switching interval of 500 ms at three different stimulation rates (low-intensity: 0-10 Hz, moderate-intensity: 0-20 Hz, and high-intensity: 0-40 Hz). The transfer function from VNS to HR was estimated with and without concomitant tonic sympathetic nerve stimulation (SNS) at 5 Hz. The asymptotic low-frequency (LF) gain (in beats/min/Hz) of the transfer function increased with SNS regardless of the VNS rate [low-intensity: 3.93 ± 0.70 vs. 5.82 ± 0.65 (P = 0.021), moderate-intensity: 3.87 ± 0.62 vs. 5.36 ± 0.53 (P = 0.018), high-intensity: 4.77 ± 0.85 vs. 7.39 ± 1.36 (P = 0.011)]. Moreover, SNS slightly increased the ratio of high-frequency (HF) gain to the LF gain. These effects of SNS were canceled by the pretreatment of ivabradine, an inhibitor of hyperpolarization-activated cyclic nucleotide-gated channels, in another group of rats (n = 6). Although background sympathetic tone antagonizes the vagal effect on mean HR, it enables finer HR control by increasing the dynamic gain of the vagal HR transfer function regardless of VNS intensity. When interpreting the HF component of HR variability, the augmenting effect from background sympathetic tone needs to be considered.

No phylogenomic support for a Cenozoic origin of the "living fossil" Isoetes.

PREMISE: The isoetalean lineage has a rich fossil record that extends to the Devonian, but the age of the living clade is unclear. Recent results indicate that it is young, from the Cenozoic, whereas earlier work based on less data from a denser taxon sampling yielded Mesozoic median ages. METHODS: We analyzed node ages in Isoetes using two genomic data sets (plastome and nuclear ribosomal cistron), three clock models implemented in MrBayes (ILN, WN, and TK02 models), and a conservative approach to calibration. RESULTS: While topological results were consistently resolved in Isoetes estimated crown group ages range from the latest Paleozoic (mid-Permian) to the Mesozoic depending on data type and clock model. The oldest estimates were retrieved using the autocorrelated TK02 clock model. An (early) Cenozoic age was only obtained under one specific condition (plastome data analyzed with the uncorrelated ILN clock model). That same plastome data set also yielded the oldest (mid-Permian) age estimate when analyzed with the autocorrelated TK02 clock model. Adding the highly divergent, recently established sister species Isoetes wormaldii to the data set approximately doubled the average median node depth to the Isoetes crown group. CONCLUSIONS: There is no consistent support for a Cenozoic origin of the living clade Isoetes. We obtained seemingly well-founded, yet strongly deviating results depending on data type and clock model. The single most important future improvement is probably to add calibration points, which requires an improved understanding of the isoetalean fossil record or alternative bases for calibration.

Auditory, tactile, and multimodal noise reduce balance variability.

Auditory and somatosensory white noise can stabilize standing balance. However, the differential effects of auditory and tactile noise stimulation on balance are unknown. Prior work on unimodal noise stimulation showed gains in balance with white noise through the auditory and tactile modalities separately. The current study aims to examine whether multimodal noise elicits similar responses to unimodal noise. We recorded the postural sway of healthy young adults who were presented with continuous white noise through the auditory or tactile modalities and through a combination of both (multimodal condition) using a wearable device. Our results replicate previous work that showed that auditory or tactile noise reduces sway variability with and without vision. Additionally, we show that multimodal noise also reduces the variability of sway. Analysis of different frequency bands of sway is typically used to separate open-loop exploratory (< 0.3 Hz) and feedback-driven (> 0.3 Hz) sway. We performed this analysis and showed that unimodal and multimodal white noise affected postural sway variability similarly in both timescales. These results support that the sensory noise effects on balance are robust across unimodal and multimodal conditions and can affect both mechanisms of sway represented in the frequency spectrum. In future work, the parameters of acoustic/tactile manipulation should be optimized for the most effective balance stabilization, and multimodal therapies should be explored for older adults with typical age-related balance instabilities.

Effects of stochastic vestibular stimulation on cognitive performance in children with ADHD.

Previous work has shown that exposure to auditory white noise (WN) can improve cognitive performance in children with ADHD, but it is unknown whether this improvement generalizes to other sensory modalities. To address this knowledge gap, we tested the effect of Stochastic Vestibular Stimulation (SVS) on cognitive performance and reaction time (RT) variability in two groups: children with ADHD and typically developing children (TDC). Children with ADHD (N=42) and TDC (N=28) performed three cognitive tasks (Spanboard, Word Recall and N-back tasks) at two different occasions, with and without exposure to SVS, in a double blinded design. The results showed no main effects of SVS on neither performance nor RT variability for children in any of the groups, and no interactions between SVS and group. Based on these results we conclude that, using our stimulation protocol, the positive effects of WN exposure on cognition in children with ADHD do not generalize to Stochastic Vestibular Stimulation.

Multi-Objective NSGA-II Optimization for Broadband Beamforming with Spherical Harmonic Domain Assistance.

Sidelobe suppression is a major challenge in wideband beamforming for acoustic research, especially in high noise and reverberation environments. In this paper, we propose a multi-objective NSGA-II wideband beamforming method based on a spherical harmonic domain for spherical microphone arrays topology. The method takes white noise gain, directional index and maximum sidelobe level as the optimization objectives of broadband beamforming, adopts the NSGA-II optimization strategy with constraints to estimate the Pareto optimal solution, and provides three-dimensional broadband beamforming capability. Our method provides superior sidelobe suppression across different spherical harmonic orders compared to commonly used multi-constrained single-objective optimal beamforming methods. We also validate the effectiveness of our proposed method in a conference room setting. The proposed method achieves a white noise gain of 8.28 dB and a maximum sidelobe level of -23.42 dB at low frequency, while at high frequency it yields comparable directivity index results to both DolphChebyshev and SOCP methods, but outperforms them in terms of white noise gain and maximum sidelobe level, measuring 16.14 dB and -25.18 dB, respectively.

Pavement Roughness Grade Recognition Based on One-dimensional Residual Convolutional Neural Network.

A pavement's roughness seriously affects its service life and driving comfort. Considering the complexity and low accuracy of the current recognition algorithms for the roughness grade of pavements, this paper proposes a real-time pavement roughness recognition method with a lightweight residual convolutional network and time-series acceleration. Firstly, a random input pavement model is established by the white noise method, and the pavement roughness of a 1/4 vehicle vibration model is simulated to obtain the vehicle vibration response data. Then, the residual convolutional network is used to learn the deep-level information of the sample signal. The residual convolutional neural network recognizes the pavement roughness grade quickly and accurately. The experimental results show that the residual convolutional neural network has a robust feature-capturing ability for vehicle vibration signals, and the classification features can be obtained quickly. The accuracy of pavement roughness classification is as high as 98.7%, which significantly improves the accuracy and reduces the computational effort of the recognition algorithm, and is suitable for pavement roughness grade classification.

Intervention strategies for white noise alleviating procedural pain in newborns: A systematic review.

AIMS AND OBJECTIVE: To systematically evaluate the current intervention strategies of white noise alleviating procedural pain in newborns. METHODS: This review was conducted following the PRISMA guideline. Seventeen databases National Guideline Clearinghouse, up to date, Clinical Evidence, BMJ best practice, Cochrane library, OVID, PubMed, Medline, EMBASE, Web of Science, CHINHAL, Medlive, China Biology Medicine disc, Chinese Clinical Trial Registry, China National Knowledge Infrastructure, China Science and Technology Journal Database, Wanfang Data Knowledge Service Platform were employed, and the studies about pain-relieving with white noise in newborns published before June 2022 was included. Quality of studies was evaluated by using the Cochrane Handbook for Systematic Reviews of Interventions. RESULTS: 18 studies were included, with sample sizes ranging from 32-296 cases. Intervention indices included duration, distance, volume, music type and outcome measure. Duration varies from study to study, from 5 min before to 5 min after the procedures. The distance was controlled at 10-60 cm, volume was controlled at 45-60 dB and music type was selected from Orhan Osman's album "Kolic" in most studies. Outcome measures included physiological indicators, neurophysiological indicators, behavioural indicators and pain score. Differences in duration leading to different white noise effects was found, but no studies have shown whether there is an effect of different volume, distance or music type. CONCLUSIONS: Based on this review, we recommend the following intervention strategies: the duration is set from 1 min before to 3 min after the procedures, the distance is decided according to the actual clinical situation, the volume is controlled at 45-55 dB (55 dB is optimal), the music type is selected to simulate intrauterine sounds, and outcome measures can choose physiological indicators, neurophysiological indictors, behavioural indicators and pain score depending on specific department and population. It is important to further explore the best intervention strategies. RELEVANCE TO CLINICAL PRACTICE: In addition to providing a set of intervention strategies, this review could be used as evidence for relieving procedural pain in newborns. PATIENT OR PUBLIC CONTRIBUTION: No Patient or Public Contribution. Data were obtained from others' literature.

The Effects of White Noise on Preprocedural Anxiety and Vital Signs Among Older Adults Undergoing Colonoscopy.

PURPOSE: A significant portion of individuals undergoing colonoscopy report stress and anxiety before the procedure. The efficacy of white noise as a nonpharmacological intervention on state anxiety and vital signs of individuals waiting for colonoscopy has not been investigated in previous studies. The current study aimed to analyze the effect of white noise on preprocedural anxiety and vital signs among older adults undergoing colonoscopy. DESIGN: A pre-test/post-test quasi-experimental study. METHODS: Subjects (N = 60) were older adults in the colonoscopy unit and divided into experimental (n = 30) and control groups (n = 30). The subjects in the experimental group listened to the white noise via binaural headphones for 20 minutes, while the control group received routine pre-endoscopic care. State anxiety and vital signs were assessed before and after intervention using the State-Trait Anxiety Inventory and vital signs monitor, respectively. The data were analyzed using SPSS-25 software. FINDINGS: No statistically significant differences were found between the two groups on demographic characteristics, state-anxiety, systolic and diastolic blood pressure, pulse rate, and respiratory rate before the intervention (P > .05). A significant difference was found between the experimental and control groups in terms of state-anxiety (P = .00) and pulse rate (P = .003) after the intervention. No significant differences were found between the two groups in terms of systolic blood pressure (P = .69), diastolic blood pressure (.59), and respiratory rate (P = .164) after the intervention. CONCLUSIONS: This study provides preliminary evidence supporting the use of white noise in older adults undergoing colonoscopy to reduce anxiety. The authors recommend that this intervention, as a nonpharmacological and easily administered approach, is adopted to reduce precolonoscopy anxiety. Continued investigation into the effect of white noise on vital signs is recommended.

Flocking Behaviors under Hierarchical Leadership of Thermodynamic Cucker-Smale Particles with Multiplicative White Noise and Perturbation.

The thermodynamic Cucker-Smale model (TCS model) describes dynamic consistency caused by different temperatures between multi-agent particles. This paper studies the flocking behaviors of the TCS model with multiplicative white noise under hierarchical leadership. First, we introduce the corresponding model of two particles. Then, by using mathematical induction and considering the properties of differential functions, it is proved that, under certain conditions, the group can achieve flocking. Finally, we verify the conclusion through numerical simulation results. Similarly, this paper studies the above model with perturbation functions.