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BACKGROUND: As technology becomes more sophisticated, more accessible methods of interpretating Big Data become essential. We have continued to develop Complexity and Entropy in Physiological Signals (CEPS) as an open access MATLAB® GUI (graphical user interface) providing multiple methods for the modification and analysis of physiological data. METHODS: To demonstrate the functionality of the software, data were collected from 44 healthy adults for a study investigating the effects on vagal tone of breathing paced at five different rates, as well as self-paced and un-paced. Five-minute 15-s recordings were used. Results were also compared with those from shorter segments of the data. Electrocardiogram (ECG), electrodermal activity (EDA) and Respiration (RSP) data were recorded. Particular attention was paid to COVID risk mitigation, and to parameter tuning for the CEPS measures. For comparison, data were processed using Kubios HRV, RR-APET and DynamicalSystems.jl software. We also compared findings for ECG RR interval (RRi) data resampled at 4 Hz (4R) or 10 Hz (10R), and non-resampled (noR). In total, we used around 190-220 measures from CEPS at various scales, depending on the analysis undertaken, with our investigation focused on three families of measures: 22 fractal dimension (FD) measures, 40 heart rate asymmetries or measures derived from Poincaré plots (HRA), and 8 measures based on permutation entropy (PE). RESULTS: FDs for the RRi data differentiated strongly between breathing rates, whether data were resampled or not, increasing between 5 and 7 breaths per minute (BrPM). Largest effect sizes for RRi (4R and noR) differentiation between breathing rates were found for the PE-based measures. Measures that both differentiated well between breathing rates and were consistent across different RRi data lengths (1-5 min) included five PE-based (noR) and three FDs (4R). Of the top 12 measures with short-data values consistently within ± 5% of their values for the 5-min data, five were FDs, one was PE-based, and none were HRAs. Effect sizes were usually greater for CEPS measures than for those implemented in DynamicalSystems.jl. CONCLUSION: The updated CEPS software enables visualisation and analysis of multichannel physiological data using a variety of established and recently introduced complexity entropy measures. Although equal resampling is theoretically important for FD estimation, it appears that FD measures may also be usefully applied to non-resampled data.

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BACKGROUND: We developed CEPS as an open access MATLAB® GUI (graphical user interface) for the analysis of Complexity and Entropy in Physiological Signals (CEPS), and demonstrate its use with an example data set that shows the effects of paced breathing (PB) on variability of heart, pulse and respiration rates. CEPS is also sufficiently adaptable to be used for other time series physiological data such as EEG (electroencephalography), postural sway or temperature measurements. METHODS: Data were collected from a convenience sample of nine healthy adults in a pilot for a larger study investigating the effects on vagal tone of breathing paced at various different rates, part of a development programme for a home training stress reduction system. RESULTS: The current version of CEPS focuses on those complexity and entropy measures that appear most frequently in the literature, together with some recently introduced entropy measures which may have advantages over those that are more established. Ten methods of estimating data complexity are currently included, and some 28 entropy measures. The GUI also includes a section for data pre-processing and standard ancillary methods to enable parameter estimation of embedding dimension m and time delay τ ('tau') where required. The software is freely available under version 3 of the GNU Lesser General Public License (LGPLv3) for non-commercial users. CEPS can be downloaded from Bitbucket. In our illustration on PB, most complexity and entropy measures decreased significantly in response to breathing at 7 breaths per minute, differentiating more clearly than conventional linear, time- and frequency-domain measures between breathing states. In contrast, Higuchi fractal dimension increased during paced breathing. CONCLUSIONS: We have developed CEPS software as a physiological data visualiser able to integrate state of the art techniques. The interface is designed for clinical research and has a structure designed for integrating new tools. The aim is to strengthen collaboration between clinicians and the biomedical community, as demonstrated here by using CEPS to analyse various physiological responses to paced breathing.

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Background: Previous research has considered the impact of personal and situational factors on treatment responses. This article documents the first phase of a four-stage project on patient characteristics that may influence responsiveness to acupuncture treatment, reporting results from an exploratory practitioner survey. Methods: Acupuncture practitioners from various medical professions were recruited through professional organisations to complete an online survey about their demographics and attitudes as well as 60 questions on specific factors that might influence treatment. They gave categorical ("Yes", "No", and "Don't know") and free-text responses. Quantitative and qualitative (thematic) analyses were then conducted. Results: There were more affirmative than negative or uncertain responses overall. Certain characteristics, including ability to relax, exercise and diet, were most often considered relevant. Younger and male practitioners were more likely to respond negatively. Limited support was found for groupings between characteristics. Qualitative data provide explanatory depth. Response fatigue was evident over the course of the survey. Conclusions: Targeting and reminders may benefit uptake when conducting survey research. Practitioner characteristics influence their appreciation of patient characteristics. Factors consistently viewed as important included ability to relax, exercise and diet. Acupuncture practitioners may benefit from additional training in certain areas. Surveys may produce more informative results if reduced in length and complexity.

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BACKGROUND: Some feelings elicited by acupuncture-type interventions are "nonspecific", interpretable as resulting from the placebo effect, our own self-healing capacities-or, indeed, the flow of qi. Expectation is thought to contribute to these nonspecific effects. Here we describe the use of two innovative 20-item questionnaires (EXPre20 and EXPost20) in a teaching situation. METHODS: Respondents were acupuncture students or practitioners on electroacupuncture (EA) training courses (N = 68). EXPre20 and EXPost20 questionnaires were completed before and after receiving individualised treatment administered by colleagues. Respondents were also asked about their prior experience of EA or transcutaneous electroacupuncture stimulation (TEAS). RESULTS: Respondents expected significantly more items to change than not to change, but significantly fewer were experienced as changing. Increases in given questionnaire items were both expected and experienced significantly more often than decreases. "Tingling", "Relaxation", and "Relief" or "Warmth" were most often expected to increase or were experienced as such, and "Pain" and "Tension" to decrease or experienced as decreasing. Expectations of change or no change were confirmed more often than not, particularly for "Tingling" and "Tension". This was not the result of the personal respondent style. Cluster analysis suggested the existence of two primary feeling clusters, "Relaxation" and "Alertness". CONCLUSIONS: Feelings experienced during or immediately after acupuncture-type interventions may depend both on prior experience and expectation.

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BACKGROUND: Despite many research publications, it is unclear how widely electroacupuncture (EA) and related modalities are used in everyday practice. It is also uncertain who uses them, for what conditions, and with what results. We aimed to survey practitioners about their use of and training in EA. We also sought to determine how much the open-access English-language database at http://www.electroacupunctureknowledge.com (EAK) is used, or might be used in the future, if updated. METHODS: A survey was developed using several rounds of consultation with a focus group and others. Professional acupuncture membership organisations were contacted to assess their willingness to notify their members. The survey was tested before its launch. RESULTS: Thirty-four professional organisations agreed to participate, together with two research bodies and six UK training institutes. Potentially, around 50 000 professionals practising acupuncture knew about the survey, to which there were 768 responses. Data were analysed for respondent demographics. Around 70% used EA, but <25% used related electrotherapy modalities. Men were more likely than women to use more than one modality. Only around 7% of respondents used non-traditional acupuncture modalities without prior training. However, awareness and usage of the EAK database was low, although around 80% of respondents stated they might use the database in the future, primarily to improve clinical practice. CONCLUSIONS: To the best of our knowledge, this is the largest survey on EA and related modalities ever conducted. As such, its results are likely to be of interest to acupuncture and other practitioners (whether or not they use EA), patients, policymakers, and funding agencies.

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INTRODUCTION: Early ceramic bearing systems in total hip arthoplasty (THA) sought to provide long term wear improvement over traditional metal on polyethylene systems. However, previous designs exhibited fractures of the ceramic acetabular liner, leading to the development of the Implex Hedrocel ceramic bearing THA system where the ceramic liner was supported on a layer of polyethylene intended to transition liner loads to the metal shell, a so-called "sandwich" design. Unfortunately, the device trial was stopped to further enrollment when liner fractures were reported. The current study examines nearly 10-year follow-up on 28 devices implanted by two surgeons at one institution in order to document ceramic bearing system performance over a longer time period. METHODS: Radiographic and patient reported outcomes, in the form of Harris Hip Scores (HHS) and 12-Item Short Form Health Survey (sF-12), were collected. RESULTS: During the study period two cups were replaced, one at three years and a second at seven years. At the five year follow-up HHS were similar to those reported in the literature for devices with traditional metal-on-polyethylene bearing surfaces and for other sandwich ceramic bearing designs. At the nine year follow-up, the HHS had not changed significantly and SF-12 scores measuring overall physical and mental health were higher than age matched national norms (p<0.001). There were no signs of cup migration, stem subsidence, osteolysis or cup loosening at any time up to the last follow-up in this patient cohort. The 89% survivorship rate and device revisions due to delamination of the liner observed in this group were similar to those reported earlier for this device and for other "sandwich design" ceramic bearing systems. DISCUSSION: This cohort did not exhibit new failure modes and HHS and SF-12 scores indicated high functionality for the majority of patients. These data suggest that a focus on preventing ceramic liner fracture through design and/or materials improvements may result in a device with long-term functionality.

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Electroacupuncture (EA) is widely used in clinical practice and research, as well as in experimental investigations into the mechanisms of acupuncture. This study explores publication trends in clinical and experimental studies of EA (1975-2011) for pain and non-pain research; EA use for different clinical conditions (1974-2012); and the relation of EA research, including stimulation frequency, to opioid peptide mechanisms. Appropriate PubMed 'all fields' searches were conducted, identified studies were classified using PubMed filters and manually, and data extracted into tables. A total of 2916 clinical studies were located, of which 19% involved EA. Additionally, 3344 animal studies were located, of which 48% involved EA. The publication rate of EA studies per year has risen over time, but the percentage of studies of pain has fallen from 60% to 25%. The conditions most commonly treated with EA are musculoskeletal, neurological, obstetric and gastrointestinal, along with intraoperative and postoperative analgesia. EA studies, particularly with low frequency stimulation, are more likely to support the role of endogenous opioid mechanisms than manual acupuncture studies, and opioid release is more likely in the central nervous system than the circulation. EA is increasingly used in clinical and especially experimental research, particularly for non-pain conditions. Acupuncture does release endogenous opioids, but this probably depends on 'dosage', with the evidence more consistent and convincing for EA than for manual acupuncture. Different frequencies of EA appear to activate different endogenous opioid mechanisms.

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BACKGROUND: Parasympathetic control of the heart is an important component in the regulation of normal cardiac function. However, the anatomic course of parasympathetic innervation of the heart is unclear. OBJECTIVE: The purpose of this study was to apply a gross parasympathetic nerve stain technique to reveal the details of the morphology of the cardiac parasympathetic nervous system. METHODS: Ten whole pig hearts were stained using a histochemical method. Immediately after sacrifice, hearts were placed in a buffered solution containing acetylthiocholine, which precipitates with acetylcholinesterase, allowing identification of cholinergic nerves. The epicardial and endocardial surfaces of the atria and ventricles were examined for nerve thickness and density. RESULTS: In both atria, nerve density was significantly greater on the endocardium, but nerve thickness was significantly greater on the epicardium. The right atrium (RA) was more densely innervated than the left atrium (LA) on the endocardium, whereas the LA was more densely innervated than the RA on the epicardium. In the ventricles, numerous thick cholinergic nerves were clearly identifiable across the epicardium, generally running parallel to the left anterior descending artery. The endocardial surfaces of the ventricles revealed a dense network of fine parasympathetic nerve fibers. As in the atria, nerve density was greater on the ventricular endocardium, but nerve thickness was greater on the epicardium. The right ventricle (RV) was more densely innervated than the left ventricle (LV), whereas the LV endocardium was more densely innervated than the RV endocardium. CONCLUSION: The epicardial and endocardial surfaces of the atria and ventricles are richly innervated by parasympathetic nerves. The density of parasympathetic innervation is heterogeneous across both the epicardial and endocardial surfaces of the heart.

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