Physiological Rates Research Articles

Retrospective evaluation of velopharyngeal insufficiency treated with Orticochea pharyngoplasty in cleft palate patients.

This study evaluated the outcomes of perceptual speech, breathing, snoring, and nasal regurgitation following Orticochea pharyngoplasty, and investigated patient characteristics associated with the resolution or improvement of velopharyngeal insufficiency (VPI) in cleft patients. The study involved a retrospective review of consecutive patients who underwent Orticochea pharyngoplasty for VPI management between 2016 and 2024 in the Department of Maxillofacial Surgery, Woman-Mother-Child Hospital, Lyon, France. Demographic data, speech and breathing characteristics, and the presence of snoring and nasal regurgitation were recorded using a standardized protocol. Preoperative and postoperative VPI severity was assessed using the Borel-Maisonny scale. All 89 patients included in the study had at least minimal VPI preoperatively (stage IIB), with 83% graded as having moderate or severe VPI. Improvement was observed in 88.76% of the patients after one surgery, and in 98.9% following a second surgery. Orticochea pharyngoplasty improved physiological breathing rates by 22% and reduced nasal regurgitation in 75% of the cases. This indicated that Orticochea pharyngoplasty is a reliable, safe, and reproducible surgical technique.

Leveraging Smart Telemedicine Technology to Enhance Nursing Care Satisfaction and Revolutionize COVID-19 Care: Prospective Cohort Study.

Telemedicine has been utilized in the care of patients with COVID-19, allowing real-time remote monitoring of vital signs. This technology reduces the risk of transmission while providing high-quality care to both self-quarantined patients with mild symptoms and critically ill patients in hospitals. This study aims to investigate the application of telemedicine technology in the care of patients with COVID-19, specifically focusing on usability, effectiveness, and patient outcomes in both home isolation and hospital ward settings. The study was conducted between January 2022 and December 2022. More than 800 cases were monitored using the QOCA remote home care system, a telemedicine platform that enables remote monitoring of physiological data-including heart rate, blood pressure, temperature, and oxygen levels-through Internet of Things devices and a 4G-connected tablet. Of these, 27 patients participated in thie study: the QOCA remote home care system was deployed 36 times in the isolation ward and 21 times to those in home isolation. The QOCA remote care system monitored isolated cases through remote care packages and a 4G tablet. Case managers and physicians provided telemedicine appointments and medications. Innovative methods were developed to enhance usage, including online health education, remote care equipment instructions via QR core links, and video consultations for patients without smartphones. A clinical nurse satisfaction survey revealed that most respondents found the content of the remote care package comprehensive and the interface easy to learn. They expressed a desire to continue using the system. The majority also agreed that using the remote care system and package would reduce their workload and that patients and caregivers could easily learn to use the package. While some respondents expressed concerns about network and Bluetooth connectivity, the majority (24/27, 89%) agreed to include the remote device as part of their routine equipment, with an average score of 84.8 points. The integration of telemedicine technology improves the quality of care while reducing the workload and exposure of health care workers to viruses.

A simplified computational liver perfusion model, with applications to organ preservation

Advanced liver preservation strategies could revolutionize liver transplantation by extending preservation time, thereby allowing for broader availability and better matching of transplants. However, developing new cryopreservation protocols requires exploration of a complex design space, further complicated by the scarcity of real human livers to experiment upon. We aim to create computational models of the liver to aid in the development of new cryopreservation protocols. Towards this goal, we present an approach for generating 3D models of the liver vasculature by building upon the space colonization algorithm. Additionally, we introduce the concept of a super lobule which enables a computational abstraction of biological liver lobules. User-tunable parameters allow for vasculatures of varying depth and topology to be generated. In each model, we solve for a common lumped resistance value assigned to the super lobules, allowing the overall physiological blood pressure and flow rate through the liver to be preserved. We demonstrate our approach’s ability to maintain consistency between models of varying depth. Finally, we simulate steady state machine perfusion of the generated models and demonstrate how they can be used to quickly test the effect of different boundary conditions when designing organ preservation protocols.

Risky behavior in virtual reality: The roles of personality, environment, and physiology.

Virtual reality (VR) provides a unique opportunity to simulate various environments, enabling the observation of human behavior in a manner that closely resembles real-world scenarios. This study aimed to explore the effects of anticipating reward or punishment, personality traits, and physiological arousal on risky decision-making within a VR context. A custom VR game was developed to simulate real-life experiences. The sample comprised 52 students (63.46% female) from the University of Novi Sad, Serbia. The study assessed four parameters within the VR environment: elapsed game time, number of steps taken, average score, and decision-making time. Three physiological signals, heart rate, skin conductance, and respiratory rate, were recorded. Results indicated that personality traits, specifically Fight (β = -0.33, p = 0.024) and Freeze (β = 0.431, p = 0.009), were significantly related to behavior in the VR environment (R = 0.572, R2_adj = 0.227, RMSE = 23.12, F(6, 40) = 3.25, p = 0.011). However, these effects were not significant after negative feedback. Emotional arousal, measured by respiratory rate amplitude (β = 0.276, p = 0.045), showed a more pronounced role after feedback (β = 0.337, p = 0.028). These findings indicate that personality traits primarily influence behavior in a VR environment prior to the actual threat, whereas environmental characteristics become more important afterwards. The results offer valuable insights for experimental and personality psychologists by revealing how risk-taking is influenced by situational, emotional, and personality factors. Additionally, they provide guidance for VR designers in creating more ecologically valid environments, highlighting VR's potential as a tool for psychological research, while also underscoring the critical importance of selecting objective VR measures to accurately capture the complexities of human behavior in immersive environments.

Improving ideological and political education with regular exercise programs: The contribution of the biosensor to cognitive development and student engagement

This research explores the impact of regular exercise programs, enhanced by biosensor technology, on the effectiveness of ideological and political education. Understanding the relationship between exercise and ideological learning is essential as educational settings increasingly combine cognitive growth with physical well-being. An ensemble of 418 students participated in this research. The information was acquired from biosensors to monitor participant’s physiological responses, body temperature, and heart rate during regular exercise, alongside assessments of their ideological engagement and understanding. A sample of students was enrolled in an 8-week program combining exercise routines with biosensor tracking. The pre-and post-test design is a critical component in assessing the effectiveness of the regular exercise program based on biosensors on ideological and political education. The information was examined using SPSS software and methods for statics encompasses descriptive statistics, regression analysis, chi-square, t-test, Pearson correlation, and analysis of variance (ANOVA) to assess the significance of changes within pre and post-test outcomes. The findings indicate that biosensor-driven exercise programs promote physical health and also enhance the efficacy of ideological and political education by developing a learning environment. Results show that compared to the pretest, taking the post-test considerably improves critical thinking skills, political discourse involvement, and ideological awareness. This study contributes to the discourse on holistic educational techniques that integrate intellectual and physical growth, indicating that regular exercise in educational curricula can have a key positive influence on the advance of knowledgeable and involved citizens.

Effects of Stepwise Combined Biofeedback Training on Attention and Self-control of High School Students Based on the Reflection and Reflexion Model

Purpose: To investigate effects of a stepwise combined biofeedback training program (SCBT) including physiological response-focused training and brainwave change-focused training based on the Reflection and Reflexion model on attention and self-control of male high school students.Methods: This research employed a non-equivalent control group pretest-posttest design. A total of 54 students from two cities in South Korea were divided into experimental, comparison, and control groups. The training consisted of ten sessions over five weeks. The experimental group participated in the SCBT, while the comparison group only engaged in physiological response-focused training. Physiological attention rate and span were used in this study to quantify attention. These measures were calculated using physiological responses. Self-control was assessed using a self-report questionnaire and changes of brainwaves in the experimental group. Data were analyzed using the statistical software SPSS/WIN 25.0.Results: Physiological attention rate, physiological attention span, and self-control scores were significantly different across the three groups. Furthermore, in the experimental group, there was a significant increase in the mean amplitude of the alpha and SMR wave while high-beta waves exhibited a notable drop.Conclusion: The present study reveals that the SCBT can serve as a distinct nursing intervention to enhance attention and self-control among high school students.

Dynamic Prediction of Physical Exertion: Leveraging AI Models and Wearable Sensor Data During Cycling Exercise.

Background/Objectives: This study aimed to explore machine learning approaches for predicting physical exertion using physiological signals collected from wearable devices. Methods: Both traditional machine learning and deep learning methods for classification and regression were assessed. The research involved 27 healthy participants engaged in controlled cycling exercises. Physiological data, including ECG, heart rate, oxygen saturation, and pedal speed (RPM), were collected during these sessions, which were divided into eight two-minute segments. Heart rate variability (HRV) was also calculated to serve as a predictive indicator. We employed two feature selection algorithms to identify the most relevant features for model training: Minimum Redundancy Maximum Relevance (MRMR) for both classification and regression, and Univariate Feature Ranking for Classification. A total of 34 traditional models were developed using MATLAB's Classification Learner App, utilizing 20% of the data for testing. In addition, Long Short-Term Memory (LSTM) networks were trained on the top features selected by the MRMR and Univariate Feature Ranking algorithms to enhance model performance. Finally, the MRMR-selected features were used for regression to train the LSTM model for predicting continuous outcomes. Results: The LSTM model for regression demonstrated robust predictive capabilities, achieving a mean squared error (MSE) of 0.8493 and an R-squared value of 0.7757. The classification models also showed promising results, with the highest testing accuracy reaching 89.2% and an F1 score of 91.7%. Conclusions: These results underscore the effectiveness of combining feature selection algorithms with advanced machine learning (ML) and deep learning techniques for predicting physical exertion levels using wearable sensor data.

Recent Developments in Surgical Treatment of Spinal Deformity in Pediatric Patients: Experience from a Single-Center Series of 42 Neurofibromatosis Type 1 Patients.

The management of spinal deformities in patients with NF-1 is challenging. The study aimed to assess the outcomes of the surgical treatment of spine deformities in children with neurofibromatosis type 1 with our treatment approach. A retrospective single-center study on pediatric patients with spinal deformities associated with NF-1 who received surgical treatment between 2006 and 2024. The study group comprised 42 patients with a mean age at surgery of 9.8 years. Twenty-five patients (60%) were treated by means of growth-preserving techniques and 17 patients (40%) by means of definitive fusion. Preoperative halo-gravity traction was used in 14 (33%) cases. In the group treated with a growth-preserving technique, a 54.1% mean curve correction was observed at the latest follow-up, and growth of the thoracic spine was maintained at a physiological rate; however, 25 unplanned revision surgeries (mostly due to mechanical complications) were necessary. In the group treated by definitive fusion, a 66% curve correction was achieved at initial surgery, which remained unchanged at latest follow-up, and revision surgery was performed in three cases for augmentation of the fusion mass. There was one neurological complication (2%). Another patient developed a deep wound infection (2%). Good and sustainable surgical correction of spinal deformities can be achieved in pediatric patients with NF-1. Due to the bony dystrophic changes, surgical treatment is challenging and the complication rate is higher than in spinal deformities of other etiologies.

Implementation and evaluation of digital twin framework for Internet of Things based healthcare systems

AbstractThe integration of digital twins (DTs) in healthcare is critical but remains limited in real‐time patient monitoring due to challenges in achieving low‐latency telemetry transmission and efficient resource management. This paper addresses these limitations by presenting a novel cloud‐based DT framework that optimises real‐time healthcare monitoring, providing a timely solution for critical healthcare needs. The framework incorporates a Pyomo‐based dynamic optimisation model, which reduces telemetry latency by 32% and improves response time by 52%, surpassing existing systems. Leveraging low‐cost, low‐latency multimodal sensors, the system continuously monitors critical physiological parameters, including SpO2, heart rate, and body temperature, enabling proactive health interventions. A DT definition language (Digital Twin Definition Language)‐based time series analysis and twin graph platform further enhance sensor connectivity and scalability. Additionally, the integration of machine learning (ML) strengthens predictive accuracy, achieving 98% real‐time accuracy and 99.58% under cross‐validation (cv = 20) using the XGBoost algorithm. Empirical results demonstrate substantial improvements in processing time, system stability, and learning capacity, with real‐time predictions completed in 17 ms. This framework represents a significant advancement in healthcare monitoring, offering a responsive and scalable solution to latency and resource constraints in real‐time applications. Future research could explore incorporating additional sensors and advanced ML models to further expand its impact in healthcare applications.

Latitudinal Clines in an Ectothermic Vertebrate: Patterns in Body Size, Growth Rate, and Reproductive Effort Suggest Countergradient Responses in the Prairie Lizard

ABSTRACTAlthough we have evidence that many organisms are exhibiting declines in body size in response to climate warming, we have little knowledge of underlying mechanisms or how associated phenotypic suites may coevolve. The better we understand coadaptations among physiology, morphology, and life history, the more accurate our predictions will be of organismal response to changing thermal environments. This is especially salient for ectotherms because they comprise 99% of species worldwide and are key to functioning ecosystems. Here, we assess body size, growth rates, and reproductive traits of a vertebrate ectotherm, the prairie lizard, Sceloporus consobrinus, for multiple populations along a latitudinal thermal gradient and compare body size clines between S. consobrinus and eastern fence lizard (S. undulatus) populations. We found that phenotypic values increased as environmental temperatures decreased for all traits examined, resulting in a pattern representative of countergradient variation. The positive covariation of phenotypes across the thermal gradient exemplifies the enigma of “master of all traits.” This enigma was further illustrated by the energy expenditure toward growth and reproduction increasing as phenotypic values increased. The evolutionary responses appear to reveal overcompensation because annual energy expenditure toward growth and reproduction increased even as activity periods decreased. Overall, compensatory responses to cooler thermal environments were exhibited by prairie lizards in body size, growth rate, egg size, and clutch size, resulting in cold‐adapted populations allocating more energy toward maintenance, growth, and reproduction than lower latitude, warm‐adapted populations. If larger body size in ectotherms is a result of intrinsically faster physiological rates compensating for cooler temperatures and shorter activity periods, then smaller body sizes in warmer environments may be a result of greater reliance on available environmental temperatures for physiological rates and time for assimilating resources.

Flow analysis of steady state forward flow of aortic valve prostheses using Particle Image Velocimetry

Abstract Transcatheter aortic valve replacement (TAVR) has become the standard therapy for aortic valve stenosis in patients with high surgical risk. Understanding the flow dynamics in TAVR is crucial for its evaluation and optimization. Experimental flow measurement by means of Particle Image Velocimetry (PIV) is increasingly applied alongside numerical analyses. This study introduces a novel test rig concept enabling the determination of velocity fields using Stereo-PIV under steady forward flow conditions through a TAVR during the peak systole matching the ISO 5840-1:2021 requirements. The experimental setup utilized an impeller pump to generate steady forward flow through a silicone aortic root model with implanted TAVR. A Stereo-PIV setup captured velocity fields in both ventricular inflow and aortic outflow regions. Test conditions were based on physiological flow rates determined from pulsatile measurements. Illumination of the added particles in the test fluid was achieved using an Nd:YAG laser. Fluorescent polystyrol particles (size: 50 μm) were used for flow visualization. Results showed characteristic flow patterns: a central jet flow entering the TAVR in the ventricular flow field. A jet flow directed towards the sinus side and a recirculation zone forming on the opposite side of the sinus could be detected in the aortic outflow. The width of the recirculation zone increases with distance from the TAVR. Maximum flow velocities were detected at 0.78 m/s for the ventricular flow field and 0.94 m/s for the aortic flow field. This study provides a comprehensive approach for fluid dynamic analysis of TAVR under steady flow conditions, offering insights into flow mechanics performance crucial for device optimization. Further investigations could enhance the PIV - measurement procedure by increasing both the spatial resolution and the tracer particle density within the acquired images for a comprehensive characterization of TAVR flow dynamics.

Performance Assessment of an Electrostatic Filter-Diverter Stent Cerebrovascular Protection Device: Evaluation of a Range of Potential Electrostatic Fields Focusing on Small Particles.

Silent Brain Infarction (SBI) is increasingly recognized in patients with cardiac conditions, particularly Atrial Fibrillation (AF) in elderly patients and those undergoing Transcatheter Aortic Valve Implantation (TAVI). While these infarcts often go unnoticed due to a lack of acute symptoms, they are associated with a threefold increase in stroke risk and are considered a precursor to ischemic stroke. Moreover, accumulating evidence suggests that SBI may contribute to the development of dementia, depression, and cognitive decline, particularly in the elderly population. The burden of SBI is substantial, with studies showing that up to 11 million Americans may experience a silent stroke annually. In AF patients, silent brain infarcts are common and can lead to progressive brain damage, even in those receiving anticoagulation therapy. The use of cerebral embolic protection devices (CEPDs) during TAVI has been explored to mitigate the risk of stroke; however, their efficacy remains under debate. Despite advancements in TAVI technology, cerebrovascular events, including silent brain lesions, continue to pose significant challenges, underscoring the need for improved preventive strategies and therapeutic approaches. We propose a device consisting of a strut structure placed at the base of the treated artery to model the potential risk of cerebral embolisms caused by atrial fibrillation, thromboembolism, or dislodged debris of varying potential TAVI patients. The study has been carried out in two stages. Both are based on computational fluid dynamics (CFD) coupled with the Lagrangian particle tracking method. The first stage of the work evaluates a variety of strut thicknesses and inter-strut spacings, contrasting with the device-free baseline geometry. The analysis is carried out by imposing flow rate waveforms characteristic of healthy and AF patients. Boundary conditions are calibrated to reproduce physiological flow rates and pressures in a patient's aortic arch. In the second stage, the optimal geometric design from the first stage was employed, with the addition of lateral struts to prevent the filtration of particles and electronegatively charged strut surfaces, studying the effect of electrical forces on the clots if they are considered charged. Flowrate boundary conditions were used to emulate both healthy and AF conditions. Results from numerical simulations coming from the first stage indicate that the device blocks particles of sizes larger than the inter-strut spacing. It was found that lateral strut space had the highest impact on efficacy. Based on the results of the second stage, deploying the electronegatively charged device in all three aortic arch arteries, the number of particles entering these arteries was reduced on average by 62.6% and 51.2%, for the healthy and diseased models respectively, matching or surpassing current oral anticoagulant efficacy. In conclusion, the device demonstrated a two-fold mechanism for filtering emboli: (1) while the smallest particles are deflected by electrostatic repulsion, avoiding micro embolisms, which could lead to cognitive impairment, the largest ones are mechanically filtered since they cannot fit in between the struts, effectively blocking the full range of particle sizes analyzed in this study. The device presented in this manuscript offers an anticoagulant-free method to prevent stroke and SBIs, imperative given the growing population of AF and elderly patients.

Metabolic balance of a marine neritic copepod under chronic and acute warming scenarios

We investigated the impact of sublethal thermal stress on physiological rates of the copepod Paracartia grani, and explored the influence of previous thermal history on this response. The copepods, originally reared at 19°C, were raised for 23 generations at 22°C and 25°C, and posteriorly exposed for 7-d to stress temperature (28°C). The copepod acclimation capacity was assessed by comparing metabolic balance at 28°C against their respective rearing temperatures. There was an inverse relationship between rearing temperature and body size and carbon content for the reared copepod lines. Weight-specific rates, except respiration, increased with rearing temperature, whereas per capita rate differences were levelled, partly due to differences in copepod size. Heat stress impact, as weight-specific rate fold-change, appeared inversely related to rearing temperature. Carbon gains were overall sufficient and slightly in excess to account for carbon losses. Gross-growth efficiency across warming scenarios was conserved, emphasizing resilience to environmental change. Our findings underscore the importance of considering the species' thermal history when predicting the response of copepod populations to climate change associated phenomena such as gradual slow ocean warming or heatwave events.

Cellular calcium handling and electrophysiology are modulated by chronic physiological pacing in human induced pluripotent stem cell-derived cardiomyocytes.

Electric pacing of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) has been increasingly used to simulate cardiac arrhythmias in vitro and to enhance cardiomyocyte maturity. However, the impact of electric pacing on cellular electrophysiology and Ca2+ handling in differentiated hiPSC-CM is less characterized. Here we studied the effects of electric pacing for 24 h or 7 days at a physiological rate of 60 beats/min on cellular electrophysiology and Ca2+ cycling in late-stage, differentiated hiPSC-CM (>90% troponin+, >60 days postdifferentiation). Electric culture pacing for 7 days did not influence cardiomyocyte cell size, apoptosis, or generation of reactive oxygen species in differentiated hiPSC-CM compared with 24-h pacing. However, epifluorescence measurements revealed that electric pacing for 7 days improved systolic Ca2+ transient amplitude and Ca2+ transient upstroke, which could be explained by elevated sarcoplasmic reticulum Ca2+ load and SERCA activity. Diastolic Ca2+ leak was not changed in line-scanning confocal microscopy, suggesting that the improvement in systolic Ca2+ release was not associated with a higher open probability of ryanodine receptor (RyR)2 during diastole. Whereas bulk cytosolic Na+ concentration and Na+/Ca2+ exchanger (NCX) activity were not changed, patch-clamp studies revealed that chronic pacing caused a slight abbreviation of the action potential duration (APD) in hiPSC-CM. We found in whole cell voltage-clamp measurements that chronic pacing for 7 days led to a decrease in late Na+ current, which might explain the changes in APD. In conclusion, our results show that chronic pacing improves systolic Ca2+ handling and modulates the electrophysiology of late-stage, differentiated hiPSC-CM. This study might help to understand the effects of electric pacing and its numerous applications in stem cell research including arrhythmia simulation.NEW & NOTEWORTHY Electric pacing is increasingly used in research with human induced pluripotent stem cell cardiomyocytes (hiPSC-CM), for example to simulate arrhythmias but also to enhance maturity. Therefore, it is mandatory to understand the effects of pacing itself on cellular electrophysiology in late-stage, matured hiPSC-CM. This study provides an electrophysiological characterization of the effects of chronic electric pacing at a physiological rate on differentiated hiPSC-CM.

Too Hot to Handle: A Meta-Analytical Review of the Thermal Tolerance and Adaptive Capacity of North American Sturgeon.

Understanding how ectotherms may fare with rising global temperatures and more frequent heatwaves is especially concerning for species already considered at-risk, such as long-lived, late-maturing sturgeon. There have been concerted efforts to collect data on the movement behavior and thermal physiology of North American sturgeon to enhance conservation efforts; thus, we sought to synthesize these data to understand how sturgeon respond to thermal stress and what capacity they have to acclimate and adapt to warming. Here, we combined a systematic literature review and meta-analysis, integrating field-based observations (distribution and spawning) and laboratory-based experiments (survival, activity, growth, metabolism, and upper thermal limits) for large-scale insights to understand the vulnerability of North American sturgeon to rising global temperatures. We summarized the preferred thermal habitat and thermal limits of sturgeon in their natural environment and using meta-analytical techniques, quantified the effect of prolonged temperature change on sturgeon whole-animal physiology and acute upper thermal limits. While acclimation did not have significant effects on physiological rates or survival overall, there were positive trends of activity and metabolism in young-of-the-year sturgeons, likely offset by negative trends of survival in early life. Notably, North American sturgeon have a greater capacity for thermal tolerance plasticity than other fishes, increasing upper thermal limits by 0.56°C per 1°C change in acclimation temperature. But with limited laboratory-based studies, more research is needed to understand if this is a sturgeon trait, or perhaps that of basal fishes in general. Importantly, with these data gaps, the fate of sturgeon remains uncertain as climate change intensifies, and physiological impacts across life stages likely limit ecological success.

Weighted Vest Combined With Vibrotactile Stimulations Decrease the Sympathetic Activity: A Repeated Measures Study.

Mental and neurological disorders are a growing global concern, further intensified by the COVID-19 pandemic. Stress management techniques, such as deep pressure therapy, have gained attention, with weighted vests commonly used for anxiety relief. However, there is limited scientific evidence supporting their efficacy. This study aimed to rigorously assess the effectiveness of a weighted vest incorporating vibrotactile stimulation in reducing anxiety by measuring physiological indicators-pulse rate and skin conductance (SC)-as well as subjective comfort ratings. A total of 30 final-semester college students participated in the study. Participants wore a vibrotactile-weighted vest, and both pulse rate and skin conductance (SC) were measured to gauge anxiety levels. Additionally, participants rated their comfort using a Comfort Rating Scale (CRS). Changes in pulse rate and SC were statistically analyzed, and effect sizes (Cohen's d) were calculated to assess the magnitude of the intervention's impact. The weighted vest with vibrotactile stimulation resulted in a significant reduction in both pulse rate (dpulse = 0.23-0.62) and SC (dsc = 0.32-0.66), indicating a small to medium effect size in anxiety reduction. Subjective evaluations of the vest using the CRS revealed low scores on discomfort-related items, with participants rating unfavorable statements between 1.5/10 and 4.6/10, suggesting overall comfort during use. This study provides compelling evidence that vibrotactile-weighted vests effectively reduce anxiety, as indicated by both physiological measures and subjective comfort ratings. The findings support the potential of this intervention as a formal therapeutic tool for stress and anxiety reduction. Further research may explore long-term effects and broader applications in clinical settings.

Metabolic Compensation Associated With Digestion in Response to the Latitudinal Thermal Environment Across Populations of the Prairie Lizard (Sceloporus consobrinus).

Environmental temperatures directly affect physiological rates in ectotherms by constraining the possible body temperatures they can achieve, with physiological processes slowing as temperatures decrease and accelerating as temperatures increase. As environmental constraints increase, as they do northward along the latitudinal thermal gradient, organisms must adapt to compensate for the slower physiological processes or decreased opportunity time. Evolving faster general metabolic rates is one adaptive response posited by the metabolic cold adaptation (MCA) hypothesis. Here we test the MCA hypothesis by examining metabolism of prairie lizard populations across the latitudinal thermal gradient. Our results show that populations from cooler environments have higher standard metabolic rates (SMRs), but these are explained by associated larger body sizes. However, metabolic rates of fed, postprandial individuals (MRFed) and metabolic energy allocated to digestion (MRΔ) were highest in the population from the coldest environment after accounting for the effect of body size. Our results suggest cold-adapted populations compensate for lower temperatures and shorter activity periods by increasing metabolic rates associated with physiological processes and thus support the MCA hypothesis. When examining energy expenditure, metabolic rates of individuals in a postprandial state (MRFed) may be more ecologically relevant than those in a postabsorptive state (SMR) and give a better picture of energy use in ectotherm populations.

Human Anterior Segment Perfusion Organ Culture.

The human anterior segment perfusion organ culture is an ex vivo model system for studying the human conventional outflow pathway with reference to pressure regulation. In this model, anterior segments dissected from human donor eyes can be fixed to a modified petri dish and perfused with media along with various study agents at the physiological flow rate of 2.5μL/min. The model mimics the one-way flow of aqueous humor in human eyes and can be used to evaluate the effects of various drugs on eye pressure in real time. Using this model, cells and tissues of the anterior segment can be maintained for up to 28days, enabling histological and molecular evaluations.

Microbiological and Haemato-biochemical Studies in Canine Pyometra

Background: Canine pyometra, is a pathological condition that results in the accumulation of purulent exudate in the uterus due to hormonal imbalance in female dogs. This is the most prevalent hormonally mediated reproductive disorder and life threatening disease of intact female dogs. The objective of the present study was to assess the physiological, haematological and biochemical changes and isolate the pathogenic microorganism present in the uterus of pyometra bitches. Methods: This study was carried out in ten bitches with a history of lethargy, depression, in appetence, polydipsia, occasional vomiting and vaginal discharge presented for treatment at the Veterinary Poly Clinic, Coimbatore, Tamil Nadu. The disease was diagnosed by history, clinical signs, physical examination, imaging techniques haematology and biochemical study. The involvement of the pathogenic organism was confirmed by microbial examination of the pus-filled uterus after the ovariohysterectomy. Result: The result showed that physiological parameters rectal temperature, heart rate and respiration rate were increased in pyometra affected dog than healthy one. The haematological parameters of red blood cell count, haemoglobin and packed cell volume were decreased in pyometra affected dogs than healthy dogs. Leukocytosis, neutrophilia, lymphocytosis, monocytosis and eosinophilia condition also observed in pyometra affected dogs. Biochemically, increased Blood urea nitrogen (BUN) creatinine and hyperprotenimia were observed in pyometra dogs. Increased activity of hepatic enzyme Alanine transaminase (ALT), Aspartate aminotransferase (AST) and Alkaline phosphatase (ALP) were also observed in pyometra dogs. The major pathogenic microorganisms involved in pyometra are Escherichia coli (40.25%), Staphylococcus (20.46%), Streptococcus (20.32%), Pseudomonas (6.41%), Proteus (6.32%) and Pasteurella (6.24%). Thus the dogs with pyometra show significant changes in physiological, haematological, biochemical parameters and growth of pathogenic microorganism in uterine fluid were the important indications of pyometra affected dogs.

Rationale and Design of OPT-RATE AF: A Randomized Clinical Trial of Increased Physiologic Pacing Rates in Heart Failure With Preserved Ejection Fraction

Cardiac physiologic pacing (CPP) after atrioventricular node (AVN) ablation for persistent atrial fibrillation (AF) has improved outcomes in patients with heart failure with reduced and preserved ejection fraction (HFpEF). Emerging evidence suggests patients with HFpEF benefit from higher heart rates, yet the optimal pacing rate after AVN ablation remains unknown. Optimal Pacing Rate for cardiac resynchronization therapy after atrioventricular node ablation in persistent Atrial Fibrillation and heart failure (OPT-RATE AF) is a prospective, randomized crossover study of patients with HFpEF after AVN ablation for persistent AF (NCT06445439). Approximately 60 patients with AF and AVN ablation, CPP, and HF with left ventricular ejection fraction ≥50% will be enrolled. Participants will be randomly assigned 1:1 to a pacing lower rate limit of 60 beats/min for 3 months and then switched to a rate of 80 beats/min for 3 months and vice versa. The primary end point is the change in exercise capacity assessed using the 6-minute walk test. Notable secondary outcomes will include changes in the Kansas City Quality of Life Questionnaire (KCCQ-12), creatinine and natriuretic peptide, and clinical events. Patient mortality and HF hospitalizations will be recorded at each phase. Electrocardiogram, echocardiogram, pacemaker interrogation, and primary and secondary outcomes will be recorded at baseline, 3 months, and 6 months. Study enrollment is ongoing and estimated to be completed by 2026. OPT-RATE AF is a randomized clinical trial that will determine the effect of a higher pacing rate in patients with persistent AF and HFpEF after AVN ablation and/or CPP. Study findings will provide insight on the role of chronotropy in improving quality of life and other important cardiovascular outcomes.