Features and frequency of use of electronic health records in primary care across 20 countries: a cross-sectional study.

OBJECTIVES: Variation exists in the capabilities of electronic healthcare records (EHRs) systems and the frequency of their use by primary care physicians (PCPs) from different settings. We aimed to examine the factors associated with everyday EHRs use by PCPs, characterise the EHRs features available to PCPs, and to identify the impact of practice settings on feature availability. STUDY DESIGN: Cross-sectional study. METHODS: PCPs from 20 countries completed cross-sectional online survey between June and September 2020. Responses which reported frequency of EHRs use were retained. Associations between everyday EHRs use and PCP and practice factors (country, urbanicity, and digital maturity) were explored using multivariable logistic regression analyses. The effect of practice factors on the variation in availability of ten EHRs features was estimated using Cramer's V. RESULTS: Responses from 1520 out of 1605 PCPs surveyed (94·7%) were retained. Everyday EHRs use was reported by 91·2% of PCPs. Everyday EHRs use was associated with PCPs working >28 h per week, having more years of experience using EHRs, country of employment, and higher digital maturity. EHRs features concerning entering, and retrieving data were available to most PCPs. Few PCPs reported having access to tools for 'interactive patient education' (37·3%) or 'home monitoring and self-testing of chronic conditions' (34·3%). Country of practice was associated with availability of all EHRs features (Cramer's V range: 0·2-0·6), particularly with availability of tools enabling patient EHRs access (Cramer's V: 0·6, P < 0.0001). Greater feature availability of EHRs features was observed with greater digital maturity. CONCLUSIONS: EHRs features intended for patient use were uncommon across countries and levels of digital maturity. Systems-level research is necessary to identify the country-specific barriers impeding the implementation of EHRs features in primary care, particularly of EHRs features enabling patient interaction with EHRs, to develop strategies to improve systems-wide EHRs use.

Biochemically recurrent prostate cancer: rationalisation of the approach to imaging.

AIM: To assess the utility of magnetic resonance imaging (MRI) in addition to the additive benefit of the conventional imaging techniques, computed tomography (CT) and nuclear medicine (NM) bone scintigraphy, for investigation of biochemical recurrence (BCR) post-prostatectomy where access to prostate specific membrane antigen (PSMA) positron-emission tomography (PET)-CT is challenging. MATERIALS AND METHODS: Relevant imaging over a 5-year period was reviewed. Ethical approval was granted by the internal review board. All patients with suspected BCR, defined as a PSA ≥0.2 ng/ml on two separate occasions, underwent a retrospective imaging review. This was performed on PACS archive search database in a single centre using search terms "PSA" and "prostatectomy" in the three imaging methods; MRI, CT, and NM bone scintigraphy. All PSMA PET CT performed were recorded. RESULTS: One hundred and eighty-five patients were identified. Patients with an MRI pelvis that demonstrated distant metastases (i.e., pelvic bone metastases or lymph node involvement more cranial to the bifurcation of the common iliac arteries) were more likely to have a positive CT and/or NM bone scintigraphy. The Pearson correlation coefficient between the findings of M1 disease at MRI pelvis and the presence of distant metastases at CT thorax, abdomen, pelvis and NM bone scintigraphy was calculated at 0.81 (p<0.01) and 0.91 (p<0.01) respectively. CONCLUSION: An imaging strategy based on risk stratification and technique-specific selection criteria leads to more appropriate use of resources, and in turn, increases the yield of conventional imaging methods. MRI prostate findings can be used to predict the additive value of CT/NM bone scintigraphy allowing a more streamlined approach to their use.

Use of esophageal stents to relieve dysphagia during neoadjuvant therapy prior to esophageal resection: a systematic review.

Esophageal cancer stenting offers symptomatic relief for patients suffering from dysphagia. There are limited data to support their use to relieve dysphagia and improve nutrition during neoadjuvant therapy with some concern that they may negatively impact oncological outcomes. The aim of this systematic review was to quantify the impact of esophageal stents on outcomes prior to resection with curative intent. A literature search was performed using Embase, Medline, PubMed, PubMed Central, the Cochrane library for articles pertaining to esophageal stent use prior to or during neoadjuvant chemotherapy or chemoradiotherapy in patients planned for curative esophagectomy. Data extracted included basic demographics, clinical, nutritional and oncologic outcomes. A total of 9 studies involving 465 patients were included. Esophageal stent use resulted in a significant improvement in mean dysphagia scores in the immediate post stent period but failed to demonstrate any positive changes in weight, body mass index (BMI) or albumin. Only 33% of stented patients ultimately progressed to potential curative surgical resection and stents were associated with reduced R0 resection rates and lower overall survival. This systematic review shows that, although esophageal stenting is associated with improvements in dysphagia during neoadjuvant therapy, their effect on improving patient nutritional status is less clear and they may be associated with poorer long-term oncological outcomes. Stents should be used with caution in patients who are being considered for potentially curative resection of esophageal malignancies and other strategies of nutritional supplementation should be considered.

Identifying patients' support needs following critical illness: a scoping review of the qualitative literature.

BACKGROUND: Intensive care survivors suffer chronic and potentially life-changing physical, psychosocial and cognitive sequelae, and supporting recovery is an international priority. As survivors' transition from the intensive care unit to home, their support needs develop and change. METHODS: In this scoping review, we categorised patients' support needs using House's Social Support Needs framework (informational, emotional, instrumental, appraisal) and mapped these against the Timing it Right framework reflecting the patient's transition from intensive care (event/diagnosis) to ward (stabilisation/preparation) and discharge home (implementation/adaptation). We searched electronic databases from 2000 to 2017 for qualitative research studies reporting adult critical care survivors' experiences of care. Two reviewers independently screened, extracted and coded data. Data were analysed using a thematic framework approach. RESULTS: From 3035 references, we included 32 studies involving 702 patients. Studies were conducted in UK and Europe (n = 17, 53%), Canada and the USA (n = 6, 19%), Australasia (n = 6, 19%), Hong Kong (n = 1, 3%), Jordan (n = 1, 3%) and multi-country (n = 1, 3%). Across the recovery trajectory, informational, emotional, instrumental, appraisal and spiritual support needs were evident, and the nature and intensity of need differed when mapped against the Timing it Right framework. Informational needs changed from needing basic facts about admission, to detail about progress and treatments and coping with long-term sequelae. The nature of emotional needs changed from needing to cope with confusion, anxiety and comfort, to a need for security and family presence, coping with flashbacks, and needing counselling and community support. Early instrumental needs ranged from managing sleep, fatigue, pain and needing nursing care and transitioned to needing physical and cognitive ability support, strength training and personal hygiene; and at home, regaining independence, strength and return to work. Appraisal needs related to obtaining feedback on progress, and after discharge, needing reassurance from others who had been through the ICU experience. CONCLUSIONS: This review is the first to identify the change in social support needs among intensive care survivors as they transition from intensive care to the home environment. An understanding of needs at different transition periods would help inform health service provision and support for survivors.

Stoma rods in abdominal surgery: a systematic review and metaanalyses.

BACKGROUND: Stoma rods are used traditionally to prevent retraction of loop stomas into the abdominal cavity. However, there is very little evidence to support or refute their use. The aim of the present systematic review and metaanalysis was to assess the current data on stoma rods in loop stomas. The primary outcomes were stoma necrosis and stoma retraction. METHODS: A systematic review and metaanalyses were conducted using the preferred reporting items for systematic reviews and metaanalysis guidelines (PRISMA). The study protocol was registered prospectively on PROSPERO. An electronic search was performed by two reviewers independently using predefined search strategy and Medline. Bibliographies of selected studies were screened for additional references. RevMan was used to generate forest plots and calculate odds ratios and 95% confidence intervals (CIs). RESULTS: In total, five studies were identified that met inclusion criteria, including four randomized controlled trials. Three studies examined only ileostomies, while one included both colostomies and ileostomies, and one only examined colostomies. In total, 561 patients underwent a stoma with a rod compared to 443 without. There was a higher rate of dermatitis (rod 29.86% vs no rod 16% OR 2.65; 95% CI 1.79-3.93) and stoma necrosis (rod 7% vs no rod 1.15% OR 5.58; 95% CI 1.85-16.84) in the rod group, but there was no significant difference in stoma retraction (rod 2.28% vs no rod 3.45%; OR 0.7; 95% CI 0.32-1.54). CONCLUSIONS: Stoma rods do not reduce the incidence of stoma retraction and instead lead to increased rates of dermatitis and stoma necrosis.

Comparing accelerometer, pedometer and a questionnaire for measuring physical activity in bronchiectasis: a validity and feasibility study?

BACKGROUND: There are challenges for researchers and clinicians to select the most appropriate physical activity tool, and a balance between precision and feasibility is needed. Currently it is unclear which physical activity tool should be used to assess physical activity in Bronchiectasis. The aim of this research is to compare assessment methods (pedometer and IPAQ) to our criterion method (ActiGraph) for the measurement of physical activity dimensions in Bronchiectasis (BE), and to assess their feasibility and acceptability. METHODS: Patients in this analysis were enrolled in a cross-sectional study. The ActiGraph and pedometer were worn for seven consecutive days and the IPAQ was completed for the same period. Statistical analyses were performed using SPSS 20 (IBM). Descriptive statistics were used; the percentage agreement between ActiGraph and the other measures were calculated using limits of agreement. Feedback about the feasibility of the activity monitors and the IPAQ was obtained. RESULTS: There were 55 (22 male) data sets available. For step count there was no significant difference between the ActiGraph and Pedometer, however, total physical activity time (mins) as recorded by the ActiGraph was significantly higher than the pedometer (mean ± SD, 232 (75) vs. 63 (32)). Levels of agreement between the two devices was very good for step count (97% agreement); and variation in the levels of agreement were within accepted limits of ±2 standard deviations from the mean value. IPAQ reported more bouted- moderate - vigorous physical activity (MVPA) [mean, SD; 167(170) vs 6(9) mins/day], and significantly less sedentary time than ActiGraph [mean, SD; 362(115) vs 634(76) vmins/day]. There were low levels of agreement between the two tools (57% sedentary behaviour; 0% MVPA10+), with IPAQ under-reporting sedentary behaviour and over-reporting MVPA10+ compared to ActiGraph. The monitors were found to be feasible and acceptable by participants and researchers; while the IPAQ was accepta ble to use, most patients required assistance to complete it. CONCLUSIONS: Accurate measurement of physical activity is feasible in BE and will be valuable for future trials of therapeutic interventions. ActiGraph or pedometer could be used to measure simple daily step counts, but ActiGraph was superior as it measured intensity of physical activity and was a more precise measure of time spent walking. The IPAQ does not appear to represent an accurate measure of physical activity in this population. TRIAL REGISTRATION: Clinical Trials Registration Number NCT01569009 : Physical Activity in Bronchiectasis.

ICORG 10-14: NEOadjuvant trial in Adenocarcinoma of the oEsophagus and oesophagoGastric junction International Study (Neo-AEGIS).

BACKGROUND: Neoadjuvant therapy is increasingly the standard of care in the management of locally advanced adenocarcinoma of the oesophagus and junction (AEG). In randomised controlled trials (RCTs), the MAGIC regimen of pre- and postoperative chemotherapy, and the CROSS regimen of preoperative chemotherapy combined with radiation, were superior to surgery only in RCTs that included AEG but were not powered on this cohort. No completed RCT has directly compared neoadjuvant or perioperative chemotherapy and neoadjuvant chemoradiation. The Neo-AEGIS trial, uniquely powered on AEG, and including comprehensive modern staging, compares both these regimens. METHODS: This open label, multicentre, phase III RCT randomises patients (cT2-3, N0-3, M0) in a 1:1 fashion to receive CROSS protocol (Carboplatin and Paclitaxel with concurrent radiotherapy, 41.4Gy/23Fr, over 5 weeks). The power calculation is a 10% difference in favour of CROSS, powered at 80%, two-sided alpha level of 0.05, requiring 540 patients to be evaluable, 594 to be recruited if a 10% dropout is included (297 in each group). The primary endpoint is overall survival, with a minimum 3-year follow up. Secondary endpoints include: disease free survival, recurrence rates, clinical and pathological response rates, toxicities of induction regimens, post-operative pathology and tumour regression grade, operative in-hospital complications, and health-related quality of life. The trial also affords opportunities for establishing a bio-resource of pre-treatment and resected tumour, and translational research. DISCUSSION: This RCT directly compares two established treatment regimens, and addresses whether radiation therapy positively impacts on overall survival compared with a standard perioperative chemotherapy regimen Sponsor: Irish Clinical Research Group (ICORG). TRIAL REGISTRATION: NCT01726452 . Protocol 10-14. Date of registration 06/11/2012.

Precision Measurement of the Radiative ß Decay of the Free Neutron.

The standard model predicts that, in addition to a proton, an electron, and an antineutrino, a continuous spectrum of photons is emitted in the ß decay of the free neutron. We report on the RDK II experiment which measured the photon spectrum using two different detector arrays. An annular array of bismuth germanium oxide scintillators detected photons from 14 to 782 keV. The spectral shape was consistent with theory, and we determined a branching ratio of 0.00335±0.00005[stat]±0.00015[syst]. A second detector array of large area avalanche photodiodes directly detected photons from 0.4 to 14 keV. For this array, the spectral shape was consistent with theory, and the branching ratio was determined to be 0.00582±0.00023[stat]±0.00062[syst]. We report the first precision test of the shape of the photon energy spectrum from neutron radiative decay and a substantially improved determination of the branching ratio over a broad range of photon energies.

Detection of evoked acetylcholine release in mouse brain slices.

The study of transmitter interactions in reward and motor pathways in the brain, including the striatum, requires methodology to detect stimulus-driven neurotransmitter release events. Such methods exist for dopamine, and have contributed to the understanding of local and behavioral factors that regulate dopamine release. However, factors that regulate release of another key transmitter in these pathways, acetylcholine (ACh), are unresolved, in part because of limited temporal and spatial resolution of current detection methods. We have optimized a voltammetric method for detection of local stimulus-evoked ACh release using enzyme-coated carbon-fiber microelectrodes and fast-scan cyclic voltammetry. These electrodes are based on the detection of H2O2 generated by the actions of acetylcholine esterase and choline oxidase, and reliably respond to ACh in a concentration-dependent manner. Methods for enzyme coating were optimized for mechanical stability that allowed for their use in ex vivo brain slices. We report here the first quantitative assessment of extracellular ACh concentration after local electrical stimulation in dorsal striatum in slices from control mice. The selective detection of ACh under these conditions was confirmed by showing that the response detected in the control slices was absent in slices from mice bred to lack ACh synthesis in the forebrain. These electrodes represent a new tool to study ACh and ACh-dopamine interactions with micrometer spatial resolution.

Do first impressions count? Frailty judged by initial clinical impression predicts medium-term mortality in vascular surgical patients.

Recognising frailty during pre-operative assessment is important. Frail patients experience higher mortality rates and are less likely to return to baseline functional status following the physiological insult of surgery. We evaluated the association between an initial clinical impression of frailty and all-cause mortality in 392 patients attending our vascular pre-operative assessment clinic. Prevalence of frailty assessed by the initial clinical impression was 30.6% (95% CI 26.0-35.2%). There were 133 deaths in 392 patients over a median follow-up period of 4 years. Using Cox regression, adjusted for age, sex, revised cardiac risk index and surgery (yes/no), the hazard ratio for mortality for frail vs. not-frail was 2.14 (95% CI 1.51-3.05). The time to 20% mortality was 16 months in the frail group and 33 months in the not-frail group. The initial clinical impression is a useful screening tool to identify frail patients in pre-operative assessment.

First-line treatment and outcome of elderly patients with primary central nervous system lymphoma (PCNSL)--a systematic review and individual patient data meta-analysis.

BACKGROUND: To investigate prognosis and effects of first-line therapy in elderly primary central nervous system lymphoma (PCNSL) patients. PATIENTS AND METHODS: A systematic review of studies about first-line therapy in immunocompetent patients ≥60 years with PCNSL until 2014 and a meta-analysis of individual patient data from eligible studies and international collaborators were carried out. RESULTS: We identified 20 eligible studies; from 13 studies, we obtained individual data of 405 patients, which were pooled with data of 378 additional patients (N = 783). Median age and Karnofsky Performance Score (KPS) was 68 years (range: 60-90 years) and 60% (range: 10%-100%), respectively. Treatments varied greatly, 573 (73%) patients received high-dose methotrexate (HD-MTX)-based therapy. A total of 276 patients received whole-brain radiotherapy (median 36 Gy, range 28.5-70 Gy). KPS ≥ 70% was the strongest prognostic factor for mortality [hazard ratio (HR) 0.50, 95% confidence interval (CI) 0.41-0.62]. After a median follow-up of 40 months, HD-MTX-based therapy was associated with improved survival (HR 0.70, 95% CI 0.53-0.93). There was no difference between HD-MTX plus oral chemotherapy and more aggressive HD-MTX-based therapies (HR 1.39, 95% CI 0.90-2.15). Radiotherapy was associated with an improved survival, but correlated with an increased risk for neurological side-effects (odds ratio 5.23, 95% CI 2.33-11.74). CONCLUSIONS: Elderly PCNSL patients benefit from HD-MTX-based therapy, especially if combined with oral alkylating agents. More aggressive HD-MTX protocols do not seem to improve outcome. WBRT may improve outcome, but is associated with increased risk for neurological side-effects. Prospective trials for elderly PCNSL patients are warranted.

The prognostic value of tumour regression grade following neoadjuvant chemoradiation therapy for rectal cancer.

AIM: To date, there is no uniform consensus on whether tumour regression grade (TRG) is predictive of outcome in rectal cancer. Furthermore, the lack of standardization of TRG grading is a major source of variability in published studies. The aim of this study was to evaluate the prognostic impact of TRG in a cohort of patients with locally advanced rectal cancer treated with neoadjuvant chemoradiation therapy (CRT). In addition to the Mandard TRG, we utilized four TRG systems modified from the Mandard TRG system and applied them to the cohort to assess which TRG system is most informative. METHOD: One-hundred and fifty-three patients with a T3/T4 and/or a node-positive rectal cancer underwent neoadjuvant 5-fluorouracil-based CRT followed by surgical resection. RESULTS: Thirty-six (23.5%) patients achieving complete pathological response (ypCR) had a 5-year disease-free survival (DFS) rate of 100% compared with a DFS rate of 74% for 117 (76.5%) patients without ypCR (P = 0.003). The Royal College of Pathologists (RCPath) TRG best condenses the Mandard five-point TRG by stratifying patients into three groups with distinct 5-year DFS rates of 100%, 86% and 67%, respectively (P = 0.001). In multivariate analysis, pathological nodal status and circumferential resection margin (CRM) status, but not TRG, remained significant predictors of DFS (P = 0.002, P = 0.035 and P = 0.310, respectively). CONCLUSION: Our findings support the notion that ypCR status, nodal status after neoadjuvant CRT and CRM status, but not TRG, are predictors of long-term survival in patients with locally advanced rectal cancer.

Exploring the use of positive psychology interventions in brain injury survivors with challenging behaviour.

OBJECTIVE: To investigate the feasibility and effectiveness of conducting two positive psychology interventions to improve mood and self-concept with survivors of traumatic brain injury (TBI), within a neuro-rehabilitation hospital. METHOD AND PROCEDURES: Ten patients with brain injury were randomly allocated to an intervention and control group. The efficacy of the first intervention, 'three positive things in life' was measured via Seligman's Authentic Happiness Index (AHI), at base-line, directly following the intervention and at the end of the 12-week group programme. The second intervention, the 'Value in Action (VIA) signature strengths intervention' was measured by the Head Injury Semantic Differential Scale (HISDS) at baseline and at the end of the group. RESULTS: Compared to baseline and control group scores, the AHI index showed an increase in the intervention group's happiness following the intervention and at the end of the 12-week programme, albeit the latter increase was non-significant. The HISDS showed non-significant improvement in self-concept and reduction in polarization of the self in the present, future and past in the second intervention. Anecdotal evidence revealed a clear improved mood following the interventions. CONCLUSION: This study shows promising results for the effectiveness of Positive Psychology interventions and methods to improve feasibility when applying this treatment within a hospital setting.

Challenging behaviour and sleep cycle disorder following brain injury: a preliminary response to agomelatine treatment.

BACKGROUND: Sleep disturbances are common after acquired brain injury. Sedatives can exacerbate behavioural disorders. OBJECTIVES: This study reports the case of a severely brain damaged man (TM) who developed a non-24 hour sleep cycle disorder that was effectively managed by the administration of a melatonin receptor agonist, agomelatine. METHOD: TM suffered significant brain damage as a result of a large subarachnoid haemorrhage of his right anterior cerebral artery complicated by midline shift and subsequent infarction of his left middle cerebral artery. In addition to challenging behaviour and cognitive impairment, TM presented with a recurrent disturbed sleep-wake pattern that significantly worsened his quality-of-life. He was diagnosed as suffering of non-24 hour sleep-wake disorder. Challenge was recorded using the Overt Aggression Scale Modified for Neuro-Rehabilitation (OASMNR). RESULTS: Typical hypnotics had no or ill effects. Agomelatine prescription (25 mg) led to significant OASMNR and sleep efficiency change with effects apparent at 1.5 years later. CONCLUSIONS: Administration of the melatonin receptor (MT1 and MT2) agonist agomelatine each night resulted in an immediate and sustained improvement on sleep and on indices of challenging behaviour.

Consultant and trainee attitudes towards supervision of operative procedures in the UK and Ireland.

The e-logbook is used to monitor progression through training and to assess training within teaching units. We document consultant and trainee opinions with regards to supervision status, and to inform guidelines for trainees and trainers using the e-logbook. A questionnaire was sent to consultants and trainees in the UK and Ireland. Eight theatre scenarios were described and respondents were asked to state what they felt was the appropriate supervision status for the trainee. Significantly more consultants in the UK use the e-logbook than those based in Ireland (58.5%:14.5%). There were differences in consensus response to the scenarios between consultants and trainees, and between Irish and UK based surgeons. We have documented the opinions of consultants and trainees from across the UK and Ireland with regards to supervision status for trainees under certain theatre situations. This information should support formal guidelines for all users of the logbook.

A comparison between different patient groups for diabetes management during phases of the COVID-19 pandemic: a retrospective cohort study in Ontario, Canada.

BACKGROUND: With the onset of the COVID-19 pandemic and the large uptake in virtual care in primary care in Canada, the care of patients with type 2 diabetes has been greatly affected. This includes decreased in-person visits, laboratory testing and in-person assessments such as blood pressure (BP). No studies have investigated if these changes persisted with pandemic progression, and it is unclear if shifts impacted patient groups uniformly. The purpose of this paper was to examine changes in diabetes care pre, early, and later pandemic across different patient groups. METHODS: A repeated cross-sectional design with an open cohort was used to investigate diabetes care in adults with type 2 diabetes for a 6-month interval from March 14 to September 13 over three consecutive years: 2019 (pre-pandemic period), 2020 (early pandemic period), and 2021 (later pandemic period). Data for this study were abstracted from the University of Toronto Practice-Based Research Network (UTOPIAN) Data Safe Haven, a primary care electronic medical records database in Ontario, Canada. Changes in diabetes care, which included primary care total visits, in-person visits, hemoglobin A1c (HbA1c) testing, and BP measurements were evaluated across the phases of the pandemic. Difference in diabetes care across patient groups, including age, sex, income quintile, prior HbA1c levels, and prior BP levels, were assessed. RESULTS: A total of 39,401 adults with type 2 diabetes were included in the study. Compared to the 6-month pre-pandemic period, having any in-person visits decreased significantly early pandemic (OR = 0.079 (0.076-0.082)), with a partial recovery later pandemic (OR = 0.162 (95% CI: 0.157-0.169). Compared to the pre-pandemic period, there was a significant decrease early pandemic for total visits (OR = 0.486 (95% CI: 0.470-0.503)), HbA1c testing (OR = 0.401 (95% CI: 0.389-0.413)), and BP measurement (OR = 0.121 (95% CI: 0.116-0.125)), with partial recovery later pandemic. CONCLUSIONS: All measures of diabetes care were substantially decreased early pandemic, with a partial recovery later pandemic across all patient groups. With the increase in virtual care due to the COVID-19 pandemic, diabetes care has been negatively impacted over 1-year after pandemic onset.

Complementarity of spike- and rate-based dynamics of neural systems.

Relationships between spiking-neuron and rate-based approaches to the dynamics of neural assemblies are explored by analyzing a model system that can be treated by both methods, with the rate-based method further averaged over multiple neurons to give a neural-field approach. The system consists of a chain of neurons, each with simple spiking dynamics that has a known rate-based equivalent. The neurons are linked by propagating activity that is described in terms of a spatial interaction strength with temporal delays that reflect distances between neurons; feedback via a separate delay loop is also included because such loops also exist in real brains. These interactions are described using a spatiotemporal coupling function that can carry either spikes or rates to provide coupling between neurons. Numerical simulation of corresponding spike- and rate-based methods with these compatible couplings then allows direct comparison between the dynamics arising from these approaches. The rate-based dynamics can reproduce two different forms of oscillation that are present in the spike-based model: spiking rates of individual neurons and network-induced modulations of spiking rate that occur if network interactions are sufficiently strong. Depending on conditions either mode of oscillation can dominate the spike-based dynamics and in some situations, particularly when the ratio of the frequencies of these two modes is integer or half-integer, the two can both be present and interact with each other.

Prevalence and implications of a difference in systolic blood pressure between one arm and the other in vascular surgical patients.

Inter-arm differences in blood pressure may confound haemodynamic management in vascular surgery. We evaluated 898 patients in the vascular pre-assessment clinic to determine the prevalence of inter-arm differences in systolic and mean arterial pressure, quantify the consequent risk of clinical error in siting monitoring peri-operatively and evaluate systolic inter-arm difference as a predictor of all-cause mortality (median follow-up 49 months). The prevalence of a systolic inter-arm difference ≥ 15 mmHg was 26% (95% CI 23-29%). The prevalence of an inter-arm mean arterial pressure difference ≥ 10 mmHg was 26% (95% CI 23-29%) and 11% (95% CI 9-13%) for a difference ≥ 15 mmHg. Monitoring could be erroneously sited in an arm reading lower for systolic pressure once in every seven to nine patients. The hazard ratio for a systolic inter-arm difference ≥ 15 mmHg vs < 15 mmHg was 1.03 (95% CI 0.78-1.36, p = 0.84). Large inter-arm blood pressure differences are common in this population, with a high potential for monitoring errors. Systolic inter-arm difference was not associated with medium-term mortality. [Correction added on 17 October 2013, after first online publication: In the Summary the sentence beginning 'We evaluated 898 patients' was corrected from (median (IQR [range]) follow-up 49 months) to read (median follow up 49 months)].

A Sister-Group Comparison of Branching and Pedicellariae in Brittlestars (Echinodermata: Ophiuroidea).

Branching of arms and presence of pedicellariae are characters among ophiuroids found only in the order Euryalida (snakestars and basketstars). Family Asteronychidae has neither character; family Euryalidae has 2 small clades with branched arms; and family Gorgonocephalidae has all species with pedicellariae and 3 or 4 clades with branched arms. Despite the rare occurrence of these characters in the Ophiuroidea, they might be key adaptations within the Euryalida that have led to relatively high diversification. Sister-group comparison of the distribution of these 2 characters among taxa indicates that neither character alone explains diversity patterns within the order. In particular, branching restricted to the tips of arms seems not strongly adaptive, probably for the lack of integration of basal forks with the disc. On the other hand, 2 clades of gorgonocephalids with basal branching exceed their snakestar sister groups in numbers of species, indicating an advantage of branching within the family. Unfortunately, the analysis cannot benefit from statistics, for at least 5 independent comparisons are required for a one-tailed sign test. Because branching and pedicellariae are probably not independent variables, future sister-group comparisons should be done only within the Gorgonocephalidae once clade structure is better clarified with increased taxon sampling (10 currently missing genera) and resolution of intra-generic inconsistencies in the most recent cladograms available. Branching might confer upon gorgonocephalid basketstars a more efficient use of pedicellariae for upstream capture of zooplankton over their snakestar relatives as well as over the Euryalidae, which retain ancestral downstream capture by mucus-laden podia.

GermanDie Verzweigung der Arme und das Vorhandensein von Pedicellarien sind Merkmale unter Ophiuroiden, die nur in der Ordnung Euryalida (Schlangensterne mit unverzweigten Armen und Korbsterne mit verzweigten Armen) vorkommen. Die Familie Asteronychidae hat kein Merkmal; die Familie Euryalidae hat zwei kleine Kladen mit verzweigten Armen; und die Familie Gorgonocephalidae hat alle Arten mit Pedicellarien und drei oder vier Kladen mit verzweigten Armen. Trotz des seltenen Vorkommens dieser Merkmale in den Ophiuroidea könnten sie Schlüsselanpassungen innerhalb der Euryalida sein, die zu einer relativ hohen Diversifizierung geführt haben. Eine Schwestergruppenanalyse der Verteilung dieser beiden Merkmale unter den Taxa zeigt, dass keines der Merkmale allein die Diversitätsmuster innerhalb der Ordnung erklärt. Insbesondere die auf die Armspitzen beschränkte Verzweigung scheint nicht stark adaptiv zu sein, wahrscheinlich wegen fehlender Integration von Basalgabeln in die Scheibe. Andererseits übertreffen zwei Kladen von Gorgonocephaliden mit basaler Verzweigung ihre Schlangenstern-Schwestergruppen in der Anzahl der Arten, was auf einen Vorteil der Verzweigung innerhalb der Familie hinweist. Leider kann die Analyse nicht von Statistiken profitieren, da für einen einseitigen Vorzeichentest mindestens fünf unabhängige Vergleiche erforderlich sind. Da Verzweigung und Pedicellariae wahrscheinlich keine unabhängigen Variablen sind, sollten zukünftige Schwestergruppenvergleiche nur innerhalb der Gorgonocephalidae durchgeführt werden, sobald die Klade-Struktur durch vermehrte Taxon-Stichproben (10 derzeit fehlende Gattungen) und durch Auflösung von Inkonsistenzen innerhalb der Gattungen in den neuesten verfügbaren Kladogrammen besser aufgeklärt ist. Die Verzweigung könnte gorgonocephaliden Korbsternen eine effizientere Nutzung von Pedicellarien für den stromaufwärts gelegenen Fang von Zooplankton gegenüber ihren Schlangenstern-Verwandten sowie gegenüber den Euryalidae verleihen, die den stromabwärts gelegenen Fang durch schleimbeladene Füsschen der Vorfahren beibehalten.