Transient Thermal Response of Tissues Surrounding an Implanted Medical Device During Inductive Charging

Inductive charging as a means of power delivery to implanted device is becoming more commonplace as increasingly sophisticated implants with higher power requirements enter clinical use. When such devices undergo inductive charging, losses within the system result in dissipated heat that must be absorbed by the surrounding tissue. The skin-mounted primary antenna and components within the implanted device such as the metal casing, battery, and secondary antenna are all susceptible to temperature increase during a charging cycle. Heating of this kind must be considered when designing modern implants utilizing this mode of power transfer in order to safeguard surrounding tissues from thermal damage, ensure patient comfort, and guarantee device longevity. The transient thermal response of tissues in the vicinity of a primary antenna and inductively charged neuromodulation implant during a charging cycle are presented in this work via a computational model incorporating device heating, tissue cooling due to blood perfusion, and multiple tissue layers. Previous studies utilizing similar numerical techniques have been conducted to investigate tissue heating, however this work seeks to transcend previous results to provide a generalized performance model across a wide range of heating conditions for a generic implanted device geometry. This will provide a useful benchmark for device manufacturers in the design of a wide variety of rechargeable implantable devices. Additionally, to maximize power transfer capability and charging performance, several thermal regulation techniques to mitigate device heating are investigated that incorporate both active and passive cooling schemes. For cases approaching 1 W heat generation within the implanted device and antenna with no applied thermal management, local tissue temperatures did not pose a significant risk of thermal tissue damage after a two-hour charging duration. At high levels of heat dissipation, however, thermal discomfort at the skin’s surface is likely to precede any actual tissue damage, thus being the limiting factor in terms of allowable heat dissipation. Comparisons against tissue temperature results for devices in clinical use proved reliability in the proposed generic model to predict maximum tissue temperatures for similar devices up to 1 W heat generation in the primary antenna and implanted device. For the four thermal regulation techniques investigated, passive standoffs at the antenna base proved most effective, decreasing max tissue temperatures by just over 1 °C

Overview of SERI's high efficiency solar cell research

The bulk of the research efforts supported by the Solar Energy Research Institute (SERI) High Efficiency Concepts area has been directed towards establishing the feasibility of achieving very high efficiencies, 30% for concentrator and more than 20% for thin film flat plate, in solar cell designs which could possibly be produced competitively. The research has accomplished a great deal during the past two years. Even though the desired performance levels have not yet been demonstrated, based on the recent progress, a greater portion of the terrestrial photovoltaics community believes that these efficiencies are attainable. The program will now allocate a larger portion of resources to low cost, large area deposition technology. The program is currently shifting greater emphasis on to the study of crystal growth in order to provide the understanding and tools needed to design a large area process

How comprehensively is evidence-based practice represented in councils on chiropractic education (CCE) educational standards: A systematic audit

Background The incorporation of evidence-based practice (EBP) is widely recognised as a necessary process for entry-level health professional training. Accreditation documents reflect the practice standards of health professions. No previous study has assessed the extent to which EBP has been taken up by chiropractic regulatory/licencing authorities, known as Councils on Chiropractic Education (CCEs), around the world. The purposes of this study were to examine CCEs' educational standards for signs of a positive and negative approach to EBP as indicated by the prevalence and use of the words evidence, research, subluxation and vitalism, and to make recommendations if significant deficiencies were found. Method We undertook a systematic audit of the educational standard documents of the various CCEs. CCEs were selected on the basis of the World Health Organisation. Two investigators identified the occurrences of terms explicitly related to EBP: evidence, evidence-based, research, subluxation and vitalism. This information was tabulated for comparative purposes. The date of the study was March 2016. Results Occurrences of the term evidence, as it related to EBP, was highest in the CCE-Europe (n = 6), followed by CCE-Australia (n = 2), and CCE-USA (n = 1). None were found in the CCE-International or CCE-Canada documents. The term research appeared most frequently in the CCE-Europe documents (n = 43), followed by CCE-USA (n-32), CCE-Australia (n = 29), CCE-Canada (n = 9) and CCE-International (n = 8). The term subluxation was found only once (CCE-USA) and vitalism did not appear in any educational standard documents. Conclusions Accreditation bodies are powerfully positioned to act as a driver for education providers to give greater priority to embedding EBP into entry-level programs and shaping future directions within the profession. Terminology relating explicitly to EBP appears to be lacking in the educational standard documentation of CCEs. Therefore, future revisions of accreditation standards should address lack of terminology

The Nordic back pain subpopulation program: predicting outcome among chiropractic patients in Finland

<p>Abstract</p> <p>Background</p> <p>In a previous Swedish study it was shown that it is possible to predict which chiropractic patients with persistent LBP will not report definite improvement early in the course of treatment, namely those with LBP for altogether at least 30 days in the past year, who had leg pain, and who did not report definite general improvement by the second treatment. The objectives of this study were to investigate if the predictive value of this set of variables could be reproduced among chiropractic patients in Finland, and if the model could be improved by adding some new potential predictor variables.</p> <p>Methods</p> <p>The study was a multi-centre prospective outcome study with internal control groups, carried out in private chiropractic practices in Finland. Chiropractors collected data at the 1st, 2^ndand 4^thvisits using standardized questionnaires on new patients with LBP and/or radiating leg pain. Status at base-line was identified in relation to pain and disability, at the 2^ndvisit in relation to disability, and "definitely better" at the 4^thvisit in relation to a global assessment. The Swedish questionnaire was used including three new questions on general health, pain in other parts of the spine, and body mass index.</p> <p>Results</p> <p>The Swedish model was reproduced in this study sample. An alternative model including leg pain (yes/no), improvement at 2^ndvisit (yes/no) and BMI (underweight/normal/overweight or obese) was also identified with similar predictive values. Common throughout the testing of various models was that improvement at the 2^ndvisit had an odds ratio of approximately 5. Additional analyses revealed a dose-response in that 84% of those patients who fulfilled none of these (bad) criteria were classified as "definitely better" at the 4^thvisit, vs. 75%, 60% and 34% of those who fulfilled 1, 2 or all 3 of the criteria, respectively.</p> <p>Conclusion</p> <p>When treating patients with LBP, at the first visits, the treatment strategy should be different for overweight/obese patients with leg pain as it should be for all patients who fail to improve by the 2^ndvisit. The number of predictors is also important.</p

The Nordic Maintenance Care Program – An interview study on the use of maintenance care in a selected group of Danish chiropractors

<p>Abstract</p> <p>Background</p> <p>Although maintenance care appears to be relatively commonly used among chiropractors, the indications for its use are incompletely understood. A questionnaire survey was recently carried out among Swedish chiropractors in order to identify their choice of various management strategies, including maintenance care. That study revealed a common pattern of choice of strategies. However, it would be necessary to verify these findings in another study population and to obtain some additional information best collected through an interview.</p> <p>Objectives</p> <p>The main aim of the present study was to attempt to reproduce the findings in the Swedish study and to obtain more information on the use of maintenance care.</p> <p>Method</p> <p>A group of 11 chiropractors were selected because they used maintenance care. They were interviewed using the questionnaire from the previous Swedish survey. The questionnaire consisted of a simple description of a hypothetical patient with low back pain and nine possible ways in which the case could develop ("scenarios"). They could choose between six different management strategies for each scenario. In addition, the chiropractors were encouraged to provide their own definition of maintenance care in an open-ended question. Interviews were taped, transcribed and analyzed. For the open-ended question, statements were identified relating to six pre hoc defined topics on the inclusion criteria/rationale for maintenance care, the frequency of treatments, and the duration of the maintenance care program.</p> <p>Results</p> <p>The open-ended question revealed that in patients with low back pain, maintenance care appears to be offered to prevent new events. The rationale was to obtain optimal spinal function. There appears to be no common convention on the frequency of treatments and duration of the treatment program was not mentioned by any of the interviewees.</p> <p>Conclusion</p> <p>The results from the questionnaire in the Danish survey showed that the response pattern for the nine scenarios was similar to that obtained in the Swedish survey. There seems to be relative agreement between chiropractors working in different countries and sampled through different methods in relation to their choice of management strategies in patients with low back pain. However, more precise information is needed on the indications for maintenance care and its treatment program, before proceeding to studying its clinical validity.</p

Correction: Who are the chiropractic students favouring a limitless scope of practice? Exploring the relationship with personality, magical thinking, and academic achievement

Following the publication of the original article [1], it has been brought to our attention that several of the provided references are mismatched in the Background section and are incorrectly recorded in the Reference section..

Who are the chiropractic students favouring a limitless scope of practice? Exploring the relationship with personality, magical thinking, and academic achievement

Introduction Some chiropractors seem to have an inflated belief in the powers of spinal manipulation (SMT), for example aiming at preventing future spinal degeneration and health problems, activities that are without supporting evidence. Non-evidenced health beliefs have been shown to be associated with a tendency toward magical thinking. Holding such beliefs about SMT is associated with a limitless scope of practice (LLSoP). Recent studies have shown that “chiropractic conservatism” (ChiroCon) is also associated with such approaches. We wanted to understand ChiroCon and these attitudes toward SMT by exploring three different factors: intolerance to uncertainty, academic achievement, and tendency toward magical thinking and how they relate to ChiroCon and LLSoP. Method A cross-sectional survey of 243 chiropractic students from an Australian chiropractic program was conducted in May 2020. Students answered a questionnaire involving a patient case-scenario for LLSoP, levels of ChiroCon, validated questionnaires on (i) Intolerance of uncertainty, (ii) Academic achievement, and (iii) Magical thinking. LLSoP was defined as wanting to treat with SMT a 5-year-old asymptomatic child for future (i) Musculoskeletal (MSK) problems and/or (ii) Non-musculoskeletal diseases. Logistic regression models were used to confirm if there was an association between ChiroCon and LLSoP and to explore associations between LLSoP and (i) Intolerance of uncertainty, (ii) Academic achievement, and (iii) Magical thinking. We repeated the same analyses using ChiroCon as the outcome variable. Results We confirmed that chiropractic students in the more extreme ChiroCon group were more likely to want to prevent future spinal disorders in an asymptomatic 5-year-old child as compared to those with lower levels (OR = 3.9, (95%CI 1.97–7.72). This was also the case for the prevention of future diseases in the same child (OR = 6.9, (95%CI 3.11–15.06). Of the three predictor variables, magical belief was positively associated with both ChiroCon and LLSoP. Conclusion Not surprisingly, ChiroCon is closely related to LLSoP and both were linked to magical thinking. Therefore, the questionnaire ‘Magical Health Beliefs’ could be a useful instrument to screen future chiropractic students to prevent a mismatch between student and institution. Depending on the outlook of the school, some schools would welcome these students, whereas other institutions would want to avoid them in their education program

Attempting to explore chiropractors and their clinical choices: An examination of a failed study

Background Recent studies have shown that psychological factors, attitudes and beliefs impact on the quality of chiropractic student clinical decisions. This association has not been studied among qualified chiropractors. Our objective was to investigate if personality, psychological factors and/or unorthodox beliefs among chiropractors are related to choices of management in specific clinical scenarios. Method In February 2018, a subsample of chiropractors (N = 700) from a practitioner-based research network in Australia known as ACORN (N = 1680), were invited to respond to an on-line anonymous questionnaire. Questions included items relating to management of specific clinical scenarios, intolerance of uncertainty (IU) and the 'Big-5' personality score, adoption of a prescriptive technique system, self-rating of chiropractic abilities, and the level of importance of subluxation and chiropractic philosophy in the delivery of care. Descriptive analysis was to be reported and associations examined between i) personality and psychology factors, unorthodox beliefs and ii) scores obtained for management of specific clinical scenarios, numbers of interdisciplinary referrals, and guideline-based X-ray use. Results The number of respondents was 141 (20%) and 33 of their responses were largely incomplete resulting in a final response rate of 108 (15.4%). In addition, some questions were left unanswered. These related mainly to IU and Big-5 personality measurements. Some sample characteristics (age, number of patients per week, hours worked per week) were similar to the larger ACORN project sample. However, the low response rate indicated that the final study sample was unlikely to be truly representative of the study population and the low number of participants made association testing unsuitable. Conclusion and recommendations The low response rate and small study sample in this study made any substantive analysis inappropriate. For these reasons, the study was not concluded. However, the potential reasons for the low response from this large database of volunteer research participants are of interest and need to be investigated. Clearly, it is necessary to engage this population better to explore sensitive issues such as personality inventories and different practice profiles in the interest of effective health care delivery and patient safety

Similarities and differences of a selection of key accreditation standards between chiropractic councils on education: A systematic review

Background Councils of Chiropractic Education (CCE) indirectly influence patient care and safety through their role of ensuring the standards of training delivered by chiropractic educational institutions. This is achieved by a process of accreditation where CCEs define and assess graduate competencies and educational standards. A previous study comparing CCE graduate competencies found variations between the CCE jurisdictions. It was proffered that variations in standards may potentially compromise patient care and safety and also inter-jurisdictional mutual recognition. This study continues the examination of CCEs by looking for similarities and differences in CCE accreditation standards. There were two purposes of this review. The first was to compare the accreditation standards, domains of accreditation standards, and components of the domains of accreditation standards as represented by the domains of "Mission, goals, vision, objectives", "Resources", "Faculty/Academic staff", "Educational program/curriculum". In addition, we compared the accreditation standards between CCEs and those of the widely accepted medical accreditation standards of the World Federation of Medical Education (WFME), in order to search for deficiencies and opportunities for improvements in these standards. The second purpose was to make recommendations, if significant deficiencies or variations were found. Method We undertook a systematic review of the similarities and differences between five CCEs' definitions of an accreditation standard and the descriptive lists of accreditation standards they have adopted. CCE selection criteria and data selection method were undertaken in a systematic manner. This information was tabulated for a comparative analysis and took place in April 2016. Results Only two CCEs had a definition of the term "accreditation / educational standard". At the domain level there was considerably more similarities than differences. The differences became more apparent when the comparisons were made at the component level. These included intended purposes of the mission statement, standards for faculty staff, requirements for clinical training by students, program budgetary autonomy and transparency, the inclusion of chiropractic philosophy and history, and which subjects should be taught in basic, behavioural and clinical sciences. Conclusions A series of recommendations were made. These included the need for an increased clarity of the required basic and clinical science subjects, teaching clinic student requirements, and faculty staff qualifications. These are proposed with the intention of creating uniform and high quality international accreditation standards for chiropractic education. Future research should compare the levels of CCEs inspection standards and processes to see if similarities and differences exist also there

Failure to define low back pain as a disease or an episode renders research on causality unsuitable: results of a systematic review

Background: Causative factors may be different for the very first onset of symptoms of the 'disease' of low back pain (LBP) than for ensuing episodes that occur after a pain-free period. This differentiation hinges on a life-time absence of low back pain at first onset and short-term absence for further episodes. In this systematic review, we explored whether researchers make these distinctions when investigating the causality of LBP. Methods: A literature search of PUBMED, CINAHL, and SCOPUS databases was performed from January 2010 until September 2016 using the search terms 'low back pain' or 'back pain' and 'risk factor' or 'caus*' or 'predict*' or 'onset' or 'first-time' or 'inception' or 'incidence'. Two reviewers extracted information on study design, types of episodes of back pain to distinguish the disease of LBP and recurring episodes, and also to determine the definitions of disease- or pain-free periods. Results: Thirty-three articles purporting to study causes of LBP were included. Upon scrutiny, 31 of the 33 articles were unclear as to what type of causality they were studying, that of the 'disease' or the episode, or a mere association with LBP. Only 9 studies used a prospective study design. Five studies appeared to investigate the onset of the disease of LBP, however, only one study truly captured the first incidence of LBP, which was the result of sports injury. Six appeared to study episodes but only one clearly related to the concept of episodes. Therefore, among those 11 studies, nine included both first-time LBP and episodes of LBP. Consequently, 22 studies related to the prevalence of LBP, as they probably included a mixture of first-time, recurring and ongoing episodes without distinction. Conclusion: Recent literature concerning the causality of LBP does not differentiate between the 'disease' of LBP and its recurring episodes mainly due to a lack of a clear definition of absence of LBP at baseline. Therefore, current research is not capable of providing a valid answer on this topic