Transcending Dimensions: a Comparative Analysis of Cloaca Imaging in Advancing the Surgeon's Understanding of Complex Anatomy.

Surgeons have a steep learning capacity to understand 2-D images provided by conventional cloacagrams. Imaging advances now allow for 3-D reconstruction and 3-D models; but no evaluation of the value of these techniques exists in the literature. Therefore, we sought to determine if advances in 3-D imaging would benefit surgeons, lead to accelerated learning, and improve understanding for operative planning of a cloaca reconstruction. Questionnaires were used to assess the understanding of 2-D and 3-D images by pediatric surgical faculty and trainees. For the same case of a cloacal malformation, a 2D contrast study cloacagram, a 3D model rotatable CT scan reconstruction, a software enhanced 3D video animation (which allowed the observer to manipulate the structure in any orientation), and a printed physical 3D cloaca model that could be held in the observer's hand were employed. Logistic mixed effect models assessed whether the proportion of questions about the case that were answered correctly differed by imaging modality, and whether the proportion answered correctly differed between trainee and attending surgeons for any particular modality. Twenty-nine pediatric surgery trainees (27 pediatric general surgery and 2 pediatric urology surgery trainees) and 30 pediatric surgery and urology faculty participated. For trainees, the percentage of questions answered correctly was: 2-D 10.5%, 3-D PACS 46.7%, 3-D Enhanced 67.1%, and 3-D Printed 73.8%. For faculty, the total percentage of questions answered correctly was: 2-D 22.2%, 3-D PACS 54.8%, 3D Enhanced 66.2%, and 3-D printed 74.0%. The differences in rates of correctness across all four modalities were significant in both fellows and attendings (p < 0.001), with performance being lowest for the 2-D modality, and with increasing percentage of correct answers with each subsequent modality. The difference between trainees and attendings in correctness rate was significant only for the 2-D modality, with attendings answering correctly more often. The 2-D cloacagram, as the least complex model, was the most difficult to interpret. The more complex the modality, the more correct were the responses obtained from both groups. Trainees and attendings had similar levels of correct answers and understanding of the cloacagram for the more advanced modalities. Mental visualization skills of anatomy and complex 3-D spatial arrangements traditionally have taken years of experience to master. Now with novel surgical education resources of a 3-D cloacagram, a more quickly advancing skill is possible.

Non-Invasive Electromagnetic Skin Patch Sensor to Measure Intracranial Fluid-Volume Shifts.

Elevated intracranial fluid volume can drive intracranial pressure increases, which can potentially result in numerous neurological complications or death. This study's focus was to develop a passive skin patch sensor for the head that would non-invasively measure cranial fluid volume shifts. The sensor consists of a single baseline component configured into a rectangular planar spiral with a self-resonant frequency response when impinged upon by external radio frequency sweeps. Fluid volume changes (10 mL increments) were detected through cranial bone using the sensor on a dry human skull model. Preliminary human tests utilized two sensors to determine feasibility of detecting fluid volume shifts in the complex environment of the human body. The correlation between fluid volume changes and shifts in the first resonance frequency using the dry human skull was classified as a second order polynomial with R² = 0.97. During preliminary and secondary human tests, a ≈24 MHz and an average of ≈45.07 MHz shifts in the principal resonant frequency were measured respectively, corresponding to the induced cephalad bio-fluid shifts. This electromagnetic resonant sensor may provide a non-invasive method to monitor shifts in fluid volume and assist with medical scenarios including stroke, cerebral hemorrhage, concussion, or monitoring intracranial pressure.

Patient-centered design criteria for wearable seizure detection devices.

INTRODUCTION: Epilepsy is a common neurological condition. Seizure diary reports and patient- or caregiver-reported seizure counts are often inaccurate and underestimated. Many caregivers express stress and anxiety about the patient with epilepsy having seizures when they are not present. Therefore, a need exists for the ability to recognize and/or detect a seizure in the home setting. However, few studies have inquired on detection device features that are important to patients and their caregivers. METHODS: A survey instrument utilizing a population of patients and caregivers was created to obtain information on the design criteria most desired for patients with epilepsy in regard to wearable devices. RESULTS: One thousand one hundred sixty-eight responses were collected. Respondents thought that sensors for muscle signal (61.4%) and heart rate (58.0%) would be most helpful followed by the O2 sensor (41.4%). There was more interest in these three sensor types than for an accelerometer (25.5%). There was very little interest in a microphone (8.9%), galvanic skin response sensor (8.0%), or a barometer (4.9%). Based on a rating scale of 1-5 with 5 being the most important, respondents felt that "detecting all seizures" (4.73) is the most important device feature followed by "text/email alerts" (4.53), "comfort" (4.46), and "battery life" (4.43) as an equally important group of features. Respondents felt that "not knowing device is for seizures" (2.60) and "multiple uses" (2.57) were equally the least important device features. Average ratings differed significantly across age groups for the following features: button, multiuse, not knowing device is for seizures, alarm, style, and text ability. The p-values were all<0.002. Eighty-two point five percent of respondents [95% confidence interval: 80.0%, 84.7%] were willing to pay more than $100 for a wearable seizure detection device, and 42.8% of respondents [95% confidence interval: 39.8%, 45.9%] were willing to pay more than $200. CONCLUSIONS: Our survey results demonstrated that patients and caregivers have design features that are important to them in regard to a wearable seizure detection device. Overall, the ability to detect all seizures rated highest among respondents which continues to be an unmet need in the community with epilepsy in regard to seizure detection. Additional uses for a wearable were not as important. Based on our results, it is important that an alert (via test and/or email) for events be a portion of the system. A reasonable price point appears to be around $200 to $300. An accelerometer was less important to those surveyed when compared with the use of heart rate, oxygen saturation, or muscle twitches/signals. As further products become developed for use in other health arenas, it will be important to consider patient and caregiver desires in order to meet the need and address the gap in devices that currently exist.

Smartphone-Based Virtual and Augmented Reality Implicit Association Training (VARIAT) for Reducing Implicit Biases Toward Patients Among Health Care Providers: App Development and Pilot Testing.

Background: Implicit bias is as prevalent among health care professionals as among the wider population and is significantly associated with lower health care quality. Objective: The study goal was to develop and evaluate the preliminary efficacy of an innovative mobile app, VARIAT (Virtual and Augmented Reality Implicit Association Training), to reduce implicit biases among Medicaid providers. Methods: An interdisciplinary team developed 2 interactive case-based training modules for Medicaid providers focused on implicit bias related to race and socioeconomic status (SES) and sexual orientation and gender identity (SOGI), respectively. The simulations combine experiential learning, facilitated debriefing, and game-based educational strategies. Medicaid providers (n=18) participated in this pilot study. Outcomes were measured on 3 domains: training reactions, affective knowledge, and skill-based knowledge related to implicit biases in race/SES or SOGI. Results: Participants reported high relevance of training to their job for both the race/SES module (mean score 4.75, SD 0.45) and SOGI module (mean score 4.67, SD 0.50). Significant improvement in skill-based knowledge for minimizing health disparities for lesbian, gay, bisexual, transgender, and queer patients was found after training (Cohen d=0.72; 95% CI -1.38 to -0.04). Conclusions: This study developed an innovative smartphone-based implicit bias training program for Medicaid providers and conducted a pilot evaluation on the user experience and preliminary efficacy. Preliminary evidence showed positive satisfaction and preliminary efficacy of the intervention.

Do Simple Analytical Models Capture Complex Fractured Bedrock Hydraulics? Oscillatory Flow Tests Suggest Not.

Fractured sedimentary bedrock aquifers represent complex flow systems that may contain fast, fracture-dominated flow paths and slower, porous media-dominated flow paths. Thus, characterizing the dynamics of flow and transport through these aquifers remains a fundamental hydrogeologic challenge. Recent studies have demonstrated the utility of a novel hydraulic testing approach, oscillatory flow testing, in field settings to characterize single bedrock fractures embedded in low-porosity sedimentary bedrock. These studies employed an idealized analytical model assuming Darcian flow through a nondeforming, constant-aperture, nonleaky fracture for data interpretation, and reported period-dependent effective fracture flow parameters. Here, we present the application of oscillatory flow testing across a range of frequencies and inter-well spacings on a fracture embedded in poorly cemented sedimentary bedrock with considerable primary porosity at the Field Site for Research in Fractured Sedimentary Rock. Consistent with previous studies, we show an apparent period-dependence in returned flow parameters, with hydraulic diffusivity decreasing and storativity increasing with increasing oscillation period, when assuming an idealized fracture conceptual model. We present simple analyses that examine non-Darcian flow and borehole storage effects as potential test design artifacts and a simple analytical model that examines fluid leakage to the surrounding host rock as a potential hydraulic mechanism that might contribute to the period-dependent flow parameters. These analyses represent a range of conceptual assumptions about fracture behavior during hydraulic testing, none of which account for the measured responses during oscillatory flow testing, leading us to argue that other hydraulic processes (e.g., aperture heterogeneity and/or fracture hydromechanics) are necessary to accurately represent pressure propagation through fractured sedimentary bedrock.

First Responder Virtual Reality Simulator to train and assess emergency personnel for mass casualty response.

As mass casualty incidents continue to escalate in the United States, we must improve frontline responder performance to increase the odds of victim survival. In this article, we describe the First Responder Virtual Reality Simulator, a high-fidelity, fully immersive, automated, programmable virtual reality (VR) simulation designed to train frontline responders to treat and triage victims of mass casualty incidents. First responder trainees don a wireless VR head-mounted display linked to a compatible desktop computer. Trainees see and hear autonomous, interactive victims who are programmed to simulate individuals with injuries consistent with an explosion in an underground space. Armed with a virtual medical kit, responders are tasked with triaging and treating the victims on the scene. The VR environment can be made more challenging by increasing the environmental chaos, adding patients, or increasing the acuity of patient injuries. The VR platform tracks and records their performance as they navigate the disaster scene. Output from the system provides feedback to participants on their performance. Eventually, we hope that the First Responder system will serve both as an effective replacement for expensive conventional training methods as well as a safe and efficient platform for research on current triage protocols.

Aquifer Characterization and Uncertainty in Multi-Frequency Oscillatory Flow Tests: Approach and Insights.

Characterizing aquifer properties and their associated uncertainty remains a fundamental challenge in hydrogeology. Recent studies demonstrate the use of oscillatory flow interference testing to characterize effective aquifer flow properties. These characterization efforts relate the relative amplitude and phase of an observation signal with a single frequency component to aquifer diffusivity and transmissivity. Here, we present a generalized workflow that relates extracted Fourier coefficients for observation signals with single and multiple frequency components to aquifer flow properties and their associated uncertainty. Through synthetic analytical modeling we show that multi-frequency oscillatory flow interference testing adds information that improves inversion performance and decreases parameter uncertainty. We show increased observation signal length, sampling frequency, and pressure sensor accuracy all produce decreased parameter uncertainty. This work represents the first attempt we are aware of to quantify effective aquifer parameters and their associated uncertainty using multi-frequency oscillatory flow interference testing.

Ultrastructural view of astrocyte arborization, astrocyte-astrocyte and astrocyte-synapse contacts, intracellular vesicle-like structures, and mitochondrial network.

The complexity of astrocyte morphology and syncytial coupling through gap junctions are crucial for astrocyte function in the brain. However, the ultrastructural details of astrocyte arborization and interactions between neighboring astrocytes remain unknown. While a prevailing view is that synapses selectively contact peripheral astrocyte processes, the precise spatial-location selectivity of synapses abutting astrocytes is unresolved. Additionally, knowing the location and quantity of vesicles and mitochondria are prerequisites to answer two emerging questions - whether astrocytes have a signaling role within the brain and whether astrocytes are highly metabolically active. Here, we provided structural context for these questions by tracing and 3D reconstructing three neighboring astrocytes using serial block-face scanning electron microscopy. Our reconstructions reveal a spongiform astrocytic morphology resulting from the abundance of reflexive and leaflet processes. At the interfaces, varying sizes of astrocyte-astrocyte contacts were identified. Inside an astrocyte domain, synapses contact the entire astrocyte, and synapse-astrocyte contacts increase from soma to terminal leaflets. In contrast to densely packed vesicles at synaptic boutons, vesicle-like structures were scant within astrocytes. Lastly, astrocytes contain dense mitochondrial networks with a mitochondrial volume ratio similar to that of neurites. Together, these ultrastructural details should expand our understanding of functional astrocyte-astrocyte and astrocyte-neuron interactions.

Efficacy of Smartphone Active and Passive Virtual Reality Distraction vs Standard Care on Burn Pain Among Pediatric Patients: A Randomized Clinical Trial.

Importance: It is unknown whether smartphone-based virtual reality (VR) games are effective in reducing pain among pediatric patients in real-world burn clinics. Objective: To evaluate the efficacy of a smartphone VR game on dressing pain among pediatric patients with burns. Design, Setting, and Participants: This randomized clinical trial included children aged 6 to 17 years who seen in the outpatient clinic of a large American Burn Association-verified pediatric burn center and level I pediatric trauma center between December 30, 2016, and January 23, 2019. Speaking English as their primary language was an inclusion criterion. Intention-to-treat data analyses were conducted from December 2019 to March 2020. Interventions: Active VR participants played a VR game; passive VR participants were immersed in the same VR environment without interactions. Both groups were compared with a standard care group. One researcher administered VR and observed pain while another researcher administered a posttrial survey that measured the child's perceived pain and VR experience. Nurses were asked to report the clinical utility. Main Outcomes and Measures: Patients self-reported pain using a visual analog scale (VAS; range, 0-100). A researcher observed patient pain based on the Face, Legs, Activity, Cry, and Consolability-Revised (FLACC-R) scale. Nurses were asked to report VR helpfulness (range, 0-100; higher scores indicate more helpful) and ease of use (range, 0-100; higher scores indicate easier to use). Results: A total of 90 children (45 [50%] girls, mean age, 11.3 years [95% CI, 10.6-12.0 years]; 51 [57%] White children) participated. Most children had second-degree burns (81 [90%]). Participants in the active VR group had significantly lower reported overall pain (VAS score, 24.9 [95% CI, 12.2-37.6]) compared with participants in the standard care control group (VAS score, 47.1 [95% CI, 32.1-62.2]; P = .02). The active VR group also had a lower worst pain score (VAS score, 27.4 [95% CI, 14.7-40.1]) than both the passive VR group (VAS score, 47.9 [95% CI, 31.8-63.9]; P = .04) and the standard care group (VAS score, 48.8 [95% CI, 31.1-64.4]; P = .03). Simulator sickness scores (range, 0-60; lower scores indicate less sickness) were similar for active VR (19.3 [95% CI, 17.5-21.1]) and passive VR groups (19.5 [95% CI, 17.6-21.5]). Nurses also reported that the VR games could be easily implemented in clinics (helpfulness, active VR: 84.2; 95% CI, 74.5-93.8; passive VR: 76.9; 95% CI, 65.2-88.7; ease of use, active VR: 94.8, 95% CI, 91.8-97.8; passive VR: 96.0, 95% CI, 92.9-99.1). Conclusions and Relevance: In this study, a smartphone VR game was effective in reducing patient self-reported pain during burn dressing changes, suggesting that VR may be an effective method for managing pediatric burn pain. Trial Registration: ClinicalTrials.gov Identifier: NCT04544631.

Virtual Reality-Based Executive Function Rehabilitation System for Children With Traumatic Brain Injury: Design and Usability Study.

BACKGROUND: Traumatic brain injury (TBI) poses a significant threat to children's health. Cognitive rehabilitation for pediatric TBI has the potential to improve the quality of life following the injury. Virtual reality (VR) can provide enriched cognitive training in a life-like but safe environment. However, existing VR applications for pediatric TBIs have primarily focused on physical rehabilitation. OBJECTIVE: This study aims to design and develop an integrative hardware and software VR system to provide rehabilitation of executive functions (EF) for children with TBI, particularly in 3 core EF: inhibitory control, working memory, and cognitive flexibility. METHODS: The VR training system was developed by an interdisciplinary team with expertise in best practices of VR design, developmental psychology, and pediatric TBI rehabilitation. Pilot usability testing of this novel system was conducted among 10 healthy children and 4 children with TBIs. RESULTS: Our VR-based interactive cognitive training system was developed to provide assistive training on core EF following pediatric TBI. Pilot usability testing showed adequate user satisfaction ratings for both the hardware and software components of the VR system. CONCLUSIONS: This project designed and tested a novel VR-based system for executive function rehabilitation that is specifically adapted to children following TBI.

Exercise limitations in a competitive cyclist twelve months post heart transplantation.

It has been well documented that for heart transplant recipients (HTrecipient) post transplantation exercise capacity does not exceed 60% of healthy age-matched controls. Few studies have been undertaken to determine the cause of exercise limitations following heart transplantation (HT) for an elite athlete. Participant was a 39 year old elite male cyclist who suffered an acute myocardial infarction after a cycling race and received a heart transplant (HT) four months later. Six weeks prior to his AMI fitness testing was completed and a predicted VO2max of 58 mL·kg(-1)·min(-1) and HRmax of 171 bpm was achieved. The participant underwent maximal exercise testing 6 and 12 months post transplant to determine exercise limitations. His results 6 and 12 months post transplant were a VO2max of 33.8 and 44.2 mL·kg(-1)·min(-1) respectively, and a HR max that was 97% and 96% of HRmax measured. The participant showed an increase in both HRmax and VO2max 12 months post HT compared to previous testing. Results suggest that the limiting factors to exercise following HT are likely due to peripheral function, which became diminished as a result accumulated from 4 months of congestive heart failure, the strain of HT, and immunosuppressive therapy leading up to the exercise testing. Lifestyle before HT and a more aggressive approach to HT recovery should be considered necessary in the improvement of peripheral functioning following HT. Key pointsPhysical work capacity following heart transplantation is not limited by cardiac denervation.Heart transplant rehabilitation should focus efforts on endothelial and muscular limitations.

A Novel Clinician-Orchestrated Virtual Reality Platform for Distraction During Pediatric Intravenous Procedures in Children With Hemophilia: Randomized Controlled Trial.

BACKGROUND: Needles are frequently required for routine medical procedures. Children with severe hemophilia require intensive intravenous (IV) therapy to treat and prevent life-threatening bleeding and undergo hundreds of IV procedures. Fear of needle-related procedures may lead to avoidance of future health care and poor clinical outcomes. Virtual reality (VR) is a promising distraction technique during procedures, but barriers to commercially available VR platforms for pediatric health care purposes have prevented widespread use. OBJECTIVE: We hypothesized that we could create a VR platform that would be used for pediatric hemophilia care, allow clinician orchestration, and be safe and feasible to use for distraction during IV procedures performed as part of complex health care. METHODS: We created a VR platform comprising wireless, adjustable, disposable headsets and a suite of remotely orchestrated VR games. The platform was customized for a pediatric hemophilia population that required hands-free navigation to allow access to a child's hands or arms for procedures. A hemophilia nurse observing the procedure performed orchestration. The primary endpoint of the trial was safety. Preliminary feasibility and usability of the platform were assessed in a single-center, randomized clinical trial from June to December 2016. Participants were children with hemophilia aged 6-18 years. After obtaining informed consent, 25 patients were enrolled and randomized. Each subject, 1 caregiver, and 1 hemophilia nurse orchestrator assessed the degree of preprocedural nervousness or anxiety with an anchored, combined modified visual analog (VAS)/FACES scale. Each participant then underwent a timed IV procedure with either VR or standard of care (SOC) distraction. Each rater assessed the distraction methods using the VAS/FACES scale at the completion of the IV procedure, with questions targeting usability, engagement, impact on procedural anxiety, impact on procedural pain, and likability of the distraction technique. Participants, caregivers, and nurses also rated how much they would like to use VR for future procedures. To compare the length of procedure time between the groups, Mann-Whitney test was used. RESULTS: Of the 25 enrolled children, 24 were included in the primary analysis. No safety concerns or VR sickness occurred. The median procedure time was 10 (range 1-31) minutes in the VR group and was comparable to 9 (range 3-20) minutes in the SOC group (P=.76). Patients in both the groups reported a positive influence of distraction on procedural anxiety and pain. Overall, in 80% (34/45) of the VR evaluations, children, caregivers, and nurses reported that they would like to use VR for future procedures. CONCLUSIONS: We demonstrated that an orchestrated, VR environment could be developed and safely used during pediatric hemophilia care for distraction during IV interventions. This platform has the potential to improve patient experience during medical procedures. TRIAL REGISTRATION: Clinical Trials.gov NCT03507582; https://clinicaltrials.gov/ct2/show/NCT03507582 (Archived by WebCite at http://www.webcitation.org/73G75upA3).

Rest Evaluation for Active Concussion Treatment (ReAct) Protocol: a prospective cohort study of levels of physical and cognitive rest after youth sports-related concussion.

INTRODUCTION: Although current guidelines for the early clinical management of sports-related concussion (SRC) call for a gradual return-to-activity, the optimal level of rest needed to promote recovery remains unknown. This paper describes the protocol of the Rest Evaluation for Active Concussion Treatment (ReAct) study which objectively measures physical and cognitive rest following SRC and its relation to recovery among youth athletes. METHODS AND ANALYSIS: Youth athletes aged 11-17 years are recruited preinjury and enrolled within 72 hours following a physician-diagnosed concussion. Injury information and acute clinical presentation are assessed at the time of injury. Youth participants are prospectively followed to objectively monitor daily physical and cognitive rest using two electronic devices: ActiGraph (to measure physical rest and sleep) and Narrative Clip (to measure cognitive rest), along with self-reported postconcussive symptoms using daily surveys. Other concussion outcomes, including functional outcomes, are assessed by surveying youth and their parents at three time points: (1) within 72 hours of injury, (2) at day 7 postenrolment and (3) at symptom resolution (or a maximum of 45 days postconcussion). ETHICS AND DISSEMINATION: This study has received ethical approval from the Institutional Review Board (IRB) at the participating institution (IRB at Nationwide Children's Hospital, IRB16-00613). The results of the study will be presented at national and international scientific conferences and published in peer-reviewed journals.

A comparative study: tongue muscle performance in weightlifters and runners.

Exercise mode (i.e., resistance training, endurance training) is known to yield mode-specific effects on strength and endurance of muscles that are directly targeted during the exercise. Such mode-specific effects can also be observed in indirectly involved (i.e., nontargeted) muscles. Mode-specific muscle performance changes of nontargeted muscles, however, have only been investigated within the skeletal system. Therefore, as a first step, this study aimed to determine if bulbar muscle performance (tongue strength [TS], tongue endurance [TE]) differs between weightlifters and runners and if group differences are tongue region-specific. The Iowa Oral Performance Instrument (IOPI) was used to measure TS and TE of the anterior and posterior tongue regions in 21 weightlifters and 23 runners. In weightlifters anterior TS was significantly greater than posterior TS (P = 0.008), whereas in runners anterior and posterior TS were comparable. Furthermore, weightlifters produced significantly greater anterior TS than runners (P = 0.001). Finally, TE was overall significantly greater in runners than in weightlifters (P = 0.001). Findings suggest that exercise mode may differentially impact performance patterns of nontargeted bulbar muscles. More research is warranted to better understand the mechanisms underlying tongue muscle performance differences between weightlifters and runners.

Mobile Technology Application for Improved Urine Concentration Measurement Pilot Study.

Objectives: Low hydration has a deleterious effect on many conditions. In the absence of a urine concentrating defect, urine concentration is a marker of hydration status. However, markers to evaluate hydration status have not been well studied in children. The objectives of this paper are to compare measures of thirst and urine concentration in children and to develop a novel mobile technology application to measure urine concentration. Study Design: Children age 12-17 years were selected (n = 21) for this pilot study. Thirst perception, specific gravity (automated dipstick analysis and refractometer), and urine color scale results were correlated to urine osmolality. The technology department developed a mobile technology camera application to measure light penetrance into urine which was tested on 25 random anonymized urine samples. Results: The patients' thirst perception and color scale as well as two researchers color scale did not significantly correlate with osmolality. Correlation between osmolality and hydration markers resulted in the following Pearson coefficients: SG automated dipstick, 0.61 (P 0.003); SG refractometer, 0.98 (P < 0.0001); urine color scale (patient), 0.37 (P 0.10), and light penetrance, -0.77 (P < 0.0001). The correlation of light penetrance with osmolality was stronger than all measures except SG by refractometer and osmolality. Conclusion: The mobile technology application may be a more accurate tool for urine concentration measurement than specific gravity by automated dipstick, subjective thirst, and urine color scale, but lags behind specific gravity measured by refractometer. The mobile technology application is a step toward patient oriented hydration strategies.

Passive Wearable Skin Patch Sensor Measures Limb Hemodynamics Based on Electromagnetic Resonance.

OBJECTIVE: The objectives of this study were to design and develop an open-circuit electromagnetic resonant skin patch sensor, characterize the fluid volume and resonant frequency relationship, and investigate the sensor's ability to measure limb hemodynamics and pulse volume waveform features. METHODS: The skin patch was designed from an open-circuit electromagnetic resonant sensor comprised of a single baseline trace of copper configured into a square planar spiral which had a self-resonating response when excited by an external radio frequency sweep. Using a human arm phantom with a realistic vascular network, the sensor's performance to measure limb hemodynamics was evaluated. RESULTS: The sensor was able to measure pulsatile blood flow which registered as shifts in the sensor's resonant frequencies. The time-varying waveform pattern of the resonant frequency displayed a systolic upstroke, a systolic peak, a dicrotic notch, and a diastolic down stroke. The resonant frequency waveform features and peak systolic time were validated against ultrasound pulse wave Doppler. A statistical correlation analysis revealed a strong correlation () between the resonant sensor peak systolic time and the pulse wave Doppler peak systolic time. CONCLUSION: The sensor was able to detect pulsatile flow, identify hemodynamic waveform features, and measure heart rate with 98% accuracy. SIGNIFICANCE: The open-circuit resonant sensor design leverages the architecture of a thin planar spiral which is passive (does not require batteries), robust and lightweight (does not have electrical components or electrical connections), and may be able to wirelessly monitor cardiovascular health and limb hemodynamics.

Circuit resistance training in chronic heart failure improves skeletal muscle mitochondrial ATP production rate--a randomized controlled trial.

BACKGROUND: We aimed to determine the role of skeletal muscle mitochondrial ATP production rate (MAPR) in relation to exercise tolerance after resistance training (RT) in chronic heart failure (CHF). METHODS AND RESULTS: Thirteen CHF patients (New York Heart Association functional class 2.3 +/- 0.5; Left ventricular ejection fraction 26 +/- 8%; age 70 +/- 8 years) underwent testing for peak total body oxygen consumption (VO(2peak)), and resting vastus lateralis muscle biopsy. Patients were then randomly allocated to 11 weeks of RT (n = 7), or continuance of usual care (C; n = 6), after which testing was repeated. Muscle samples were analyzed for MAPR, metabolic enzyme activity, and capillary density. VO(2peak) and MAPR in the presence of the pyruvate and malate (P+M) substrate combination, representing carbohydrate metabolism, increased in RT (P < .05) and decreased in C (P < .05), with a significant difference between groups (VO(2peak), P = .005; MAPR, P = .03). There was a strong correlation between the change in MAPR and the change in peak total body oxygen consumption (VO(2peak)) over the study (r = 0.875; P < .0001), the change in MAPR accounting for 70% of the change in VO(2peak). CONCLUSIONS: These findings suggest that mitochondrial ATP production is a major determinant of aerobic capacity in CHF patients and can be favorably altered by muscle strengthening exercise.

Case report on PWC of a competitive cyclist before and after heart transplant.

INTRODUCTION: It has been well documented that for heart transplant recipients (HTR), posttransplantation physical work capacity (PWC) normally does not exceed 60% of the value for healthy age-matched controls. Few, if any, studies have undertaken posttransplantation PWC measurements of well-conditioned individuals (i.e., PWC>300 W). CASE SUMMARY: A 37-yr-old professionally trained male cyclist suffered an acute myocardial infarction (AMI) immediately after a road race and received a heart transplant (HT) 4 months after the AMI. The participant resumed training 1 month after surgery and underwent a maximal exercise test 6 months after surgery. Peak PWC (33.8 mL.kg(-1).min(-1), 250 W) was 92% of the age-predicted maximum, and peak heart rate (165 bpm) was 96% of his known maximum. These results were similar to the participants in a study who had been training regularly for 36+/-24 months before testing, and PWC evaluations occurred 43+/-12 months after HT. CONCLUSION: Results suggest that 1) lifestyle before HT may positively affect posttransplantation PWC, 2) exercise capacity was not limited by chronotropic incompetence, and 3) a more aggressive approach to HT recovery could be applied to HTR with similar activity histories.

Tongue strength and endurance: Comparison in active and non-active young and older adults.

PURPOSE: Tongue strength and endurance are important for swallowing and upper airway patency. Physical activity positively affects targeted and non-targeted skeletal muscles; however, little is known about the indirect effect of physical activity on tongue muscles. This study sought to determine if tongue muscle performance differs between highly active and non-active individuals and if such an effect varies with age. METHOD: Forty-eight healthy adults were divided into two age groups (24 young, 20.96 ± 3.22 years; 24 older, 65 ± 3.72 years) and further divided into highly active and non-active based on The General Practice Physical Activity Questionnaire. Tongue strength (TS) and tongue endurance (TE) were obtained using the Iowa Oral Performance Instrument. RESULT: A significant main effect of activity level on TS and TE was found. Although the main effect of age on TS and TE and age × activity level interactions were not significant, the effect of activity level on TS and TE was more pronounced in older adults than younger adults. CONCLUSION: Findings suggest physical activity may affect TS and TE, particularly in older adults. Future research is warranted to understand the underlying mechanisms contributing to these group differences. Clinical implications of these findings are discussed.