A Modular Digital Twinning Framework for Safety Assurance of Collaborative Robotics

Digital twins offer a unique opportunity to design, test, deploy, monitor, and control real-world robotic processes. In this paper we present a novel, modular digital twinning framework developed for the investigation of safety within collaborative robotic manufacturing processes. The modular architecture supports scalable representations of user-defined cyber-physical environments, and tools for safety analysis and control. This versatile research tool facilitates the creation of mixed environments of Digital Models, Digital Shadows, and Digital Twins, whilst standardising communication and physical system representation across different hardware platforms. The framework is demonstrated as applied to an industrial case-study focused on the safety assurance of a collaborative robotic manufacturing process. We describe the creation of a digital twin scenario, consisting of individual digital twins of entities in the manufacturing case study, and the application of a synthesised safety controller from our wider work. We show how the framework is able to provide adequate evidence to virtually assess safety claims made against the safety controller using a supporting validation module and testing strategy. The implementation, evidence and safety investigation is presented and discussed, raising exciting possibilities for the use of digital twins in robotic safety assurance.

Adjudicating Mild Cognitive Impairment Due to Alzheimer's Disease as a Novel Endpoint Event in the TOMMORROW Prevention Clinical Trial

BACKGROUND

The onset of mild cognitive impairment (MCI) is an essential outcome in Alzheimer's disease (AD) prevention trials and a compelling milestone for clinically meaningful change. Determining MCI, however, may be variable and subject to disagreement. Adjudication procedures may improve the reliability of these determinations. We report the performance of an adjudication committee for an AD prevention trial.

METHODS

The TOMMORROW prevention trial selected cognitively normal participants at increased genetic risk for AD and randomized them to low-dose pioglitazone or placebo treatment. When adjudication criteria were triggered, a participant's clinical information was randomly assigned to a three-member panel of a six-member independent adjudication committee. Determination of whether or not a participant reached MCI due to AD or AD dementia proceeded through up to three review stages - independent review, collaborative review, and full committee review - requiring a unanimous decision and ratification by the chair.

RESULTS

Of 3494 participants randomized, the committee adjudicated on 648 cases from 386 participants, resulting in 96 primary endpoint events. Most participants had cases that were adjudicated once (n = 235, 60.9%); the rest had cases that were adjudicated multiple times. Cases were evenly distributed among the eight possible three-member panels. Most adjudicated cases (485/648, 74.8%) were decided within the independent review (stage 1); 14.0% required broader collaborative review (stage 2), and 11.1% needed full committee discussion (stage 3). The primary endpoint event decision rate was 39/485 (8.0%) for stage 1, 29/91 (31.9%) for stage 2, and 28/72 (38.9%) for stage 3. Agreement between the primary event outcomes supported by investigators' clinical diagnoses and the decisions of the adjudication committee increased from 50% to approximately 93% (after around 100 cases) before settling at 80-90% for the remainder of the study.

CONCLUSIONS

The adjudication process was designed to provide independent, consistent determinations of the trial endpoints. These outcomes demonstrated the extent of uncertainty among trial investigators and agreement between adjudicators when the transition to MCI due to AD was prospectively assessed. These methods may inform clinical endpoint determination in future AD secondary prevention studies. Reliable, accurate assessment of clinical events is critical for prevention trials and may mean the difference between success and failure.

Collision cascades overlapping with self-interstitial defect clusters in Fe and W

Overlap of collision cascades with previously formed defect clusters become increasingly likely at radiation doses typical for materials in nuclear reactors. Using molecular dynamics, we systematically investigate the effects of different pre-existing self-interstitial clusters on the damage produced by an overlapping cascade in bcc iron and tungsten. We find that the number of new Frenkel pairs created in direct overlap with an interstitial cluster is reduced to essentially zero, when the size of the defect cluster is comparable to that of the disordered cascade volume. We develop an analytical model for this reduced defect production as a function of the spatial overlap between a cascade and a defect cluster of a given size. Furthermore, we discuss cascade-induced changes in the morphology of self-interstitial clusters, including transformations between [Formula: see text] and [Formula: see text] dislocation loops in iron and tungsten, and between C15 clusters and dislocation loops in iron. Our results provide crucial new cascade-overlap effects to be taken into account in multi-scale modelling of radiation damage in bcc metals.

Problem behaviours and psychotropic medication use in intellectual disability: a multinational cross-sectional survey

BACKGROUND

Problem behaviours (PBs) are a common cause for clinician contact in people with disorders of intellectual development and may be a common cause for the prescription of psychotropic medication. We aimed to use a large, multinational sample to define the prevalence of PBs, the associations with psychotropic medication use, and to assess for any potential 'diagnostic overshadowing' by the label of PBs in a population of people with disorders of intellectual development.

METHOD

A multinational, multi-setting, cross-sectional service evaluation and baseline audit was completed. Data were collected from UK hospitals, UK community settings, Sri Lanka and Hong Kong. A semi-structured questionnaire was completed by treating clinicians, capturing demographic details, prevalence rates of intellectual disability and psychotropic medication use, alongside psychiatric co-morbidity.

RESULTS

A sample size of 358 was obtained, with 65% of included participants treated in an inpatient setting. Psychotropic use was prevalent (90%) in our sample, particularly antipsychotics (74%). The prevalence of PB was high (83%). There was no statistically significant association between psychotropic prescription and recorded psychiatric co-morbidity, suggesting prevalent 'off-label' use for PBs, or poor recording of psychiatric co-morbidity. There was some evidence of possible diagnostic overshadowing due to the PB classification. A higher dose of psychotropic medication was associated with aggression toward others (P = 0.03).

CONCLUSIONS

We found evidence of prevalent potential 'off-label' use for psychotropic medication, which may be due to PBs. We also found evidence of potential diagnostic-overshadowing, where symptoms of psychiatric co-morbidity may have been attributed to PBs. Our findings provide renewed importance, across borders and health systems, for clinicians to consider a holistic approach to treating PBs, and attempting to best understand the precipitants and predisposing factors before psychotropic prescribing.

Psychiatry of learning disability – a future with mental health?

Aims and Method

A postal survey was sent to all consultants in the psychiatry of learning disability from four English regions. Their views on job satisfaction, their core roles and the management re-structuring of services were elicited.

Results

The proportion agreeing or strongly agreeing with each management option was 79% for integrated mental health–learning disability trusts, 61% for specialist learning disability trusts, 47% for care trusts, 10% for primary care trusts and 5% for social services. Only 34% felt consulted or able to influence the process of change and only 33% were satisfied with the current management changes within their trust but 67% were satisfied overall with their jobs.

Clinical Implications

Management from integrated mental health–learning disability trusts is the most preferred option for psychiatrists in learning disability. A large number of consultants, though otherwise satisfied with their jobs, feel excluded or unable to influence the current changes in management structures. A model of integrated service provision in line with the government's learning disability strategy is presented.

Head banging as a form of self-harm among inpatients within forensic mental health and intellectual disability services

Introduction

“Head banging” is a common form of self-harm, linked to numerous negative outcomes including significant brain damage. However, little research has investigated the prevalence and correlates of head banging behaviour in clinical populations.

Method

Head banging episodes were identified from the incident records (n = 5417) of two inpatient forensic services (one intellectual disability and one mental health), using relevant search terms. Rates were compared between individual patients, by gender, diagnosis and level of security. Incident accounts were analysed qualitatively using thematic analysis.

Results

Two hundred and twenty nine incidents of head banging were recorded, occurring approximately every three days in each service. The prevalence of the behaviour between individual patients varied widely, ranging from one to 38 incidents within one year. Women and patients with intellectual disability appeared more likely to engage in head banging. Qualitative incident reports indicated that head banging was associated with mental distress, anger, and psychotic experiences.

Discussion

Head banging occurs frequently in forensic services, and has documented associations with traumatic brain injury in affected individuals, thus negatively impacting progress through the care pathway and treatment outcomes. Further research should investigate short and long term management strategies and treatment approaches, in order to minimise harm.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

A Systematic Review and Synthesis of Outcome Domains for use Within Forensic Services for People with Intellectual Disabilities

Aims

In response to the Winterbourne scandal, and the large number of people with intellectual disabilities (IDs) and offending behavior being treated in psychiatric hospitals, this study identified the domains that should be used to measure treatment outcomes of this group.

Methods

A systematic search of relevant databases was undertaken to identify domains. Sixty studies met the eligibility criteria, and findings were synthesized using content analysis. The findings were refined within a consultation and consensus exercises with carers, service users, and experts.

Results

The final framework encompassed three a priori super-ordinate domains (a) effectiveness, (b) patient safety, and (c) patient and carer experience. Within each of these, further sub-domains emerged from our systematic review and consultation exercises. These included severity of clinical symptoms, offending behaviors, reactive and restrictive interventions, quality of life and patient satisfaction.

Conclusions

To index recovery, services need to measure outcome using this framework.

The prevalence of obesity among forensic intellectual disability inpatients

Background

Inpatient mental health settings have been described as “obesogenic” environments, due to factors including psychotropic medication, high calorie food, restricted physical activity and sedentary lifestyles. No research has investigated obesity among forensic intellectual disability inpatients, despite this populations’ increased risk. Therefore, this paper aims to evaluate the prevalence and correlates of overweight and obesity on, and during admission.

Method

The weight and body mass index data of 46 inpatients (15 women and 31 men) within a specialist intellectual disability forensic service was examined for the study.

Results

Only six patients (13%) were a normal weight at admission, whereas 40 (87%) were overweight or obese. During their admission, 28 (61%) gained weight (average 11.8 kg), and one (2%) maintained. However, 17 patients (37%) lost weight (average 6.2 kg), though 16 remained in overweight/obese categories. There was no correlation between length of stay and weight/BMI.

Conclusions

The majority of patients were overweight or obese on admission, and approximately 60% gained weight during their admission. Women appeared at greater risk of obesity. There was no relationship between length of stay and weight. This is potentially due to the high prevalence of obesity on admission and the impact of previous admissions on weight. The results highlight the need for effective weight management interventions with this population.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Well-being in wounds inventory (WOWI): development of a valid and reliable measure of well-being in patients with wounds

OBJECTIVE

Physical and psychosocial deficits have been reported in people living with chronic wounds. While the negative impact of these factors on an individual's quality of life (QoL) is well documented, there has been little research into the well-being of those living with chronic wounds, despite recent calls for increased attention to this related, yet distinct construct. This paper introduces the Well-being in Wounds Inventory (WOWI) and provides support for the WOWI as a valid and reliable measure of well-being in patients living with chronic wounds.

METHOD

A draft questionnaire was administered to a convenience sample of individuals with chronic wounds (n=85) and the resulting data subject to factor analysis in order to refine the structure of the questionnaire. The reliability, validity and responsiveness of the resulting questionnaire were then tested by administration to a second sample of individuals with wounds (n=49). Socio-demographic data, issues affecting patient well-being and well-being factors, such as, emotions; perceived coping skills; social support; personal control; hope for the future, were measured.

RESULTS

Results confirmed the WOWI as a reliable and valid measure of well-being. Items loaded onto two subscales, 'personal resources' and 'wound worries'. Analysis revealed the WOWI to be highly feasible measure of well-being, with good test-retest reliability and responsiveness to changes in health status.

CONCLUSION

The current study highlights the importance of assessing well-being factors in individuals living with chronic wounds. It introduces the WOWI as a valid and reliable measure of well-being in chronic wound patients. The authors recommend health-care practitioners take account of well-being as part of a holistic treatment plan in order to maximise patient outcomes.

DECLARATION OF INTEREST

This project was funded by Urgo Medical. The authors have no conflict of interest to declare.

A Mobile Climbing Robot for High Precision Manufacture and Inspection of Aerostructures

In this paper we describe the design, development, and experimental trials of a climbing robot for manufacturing and inspection applications within the aerospace industry. We describe the mechanical platform, which utilizes vacuum for attachment to vertical and overhanging surfaces, and a traction system that enables rapid movement of the robot over planar and curved surfaces of any orientation. The main applications considered during the research were the manufacturing processes for large external surface structures such as wings and the post-manufacturing and in-service inspection of such structures. The design of suitable tool packages for manufacturing and non-destructive testing is considered in the paper. The first tool package to be implemented and tested was a five-axis high precision drill, which is described. The control system is described within this paper along with the software architecture. The software architecture for the robot was generalized, allowing different robot configurations to be described and implemented rapidly through structured configuration files. Particular attention is paid to the robot’s localization and navigation system, which provides tool point precision to aircraft manufacturing tolerances. The localization system uses data from several different types of sensors and combines these with information provided by a surface model to derive six-degrees-of-freedom position and orientation using an extended Kalman filter to fuse the state information from the different sources. Tool point position is calculated through direct kinematic transformations. Improvements to this work are described, which utilize one of the initial releases of Lieca’s new six-degrees-of-freedom precision measurement instruments, the Lieca LTD-800. We also summarize the experimental trials and the initial performance in terms of tool point precision and climbing performance. The concept of application of the robot and details of the technologies included in the robot that are outlined in this paper are the subject of separate pending patent applications filed by BAE SYSTEMS plc.

Enhanced recovery after surgery (ERAS) for head and neck oncology patients

OBJECTIVES

To describe the development of an enhanced recovery after surgery (ERAS) protocol for people undergoing surgery for head and neck cancer.

DESIGN

Service improvement project.

PARTICIPANTS

Head and neck oncology patients.

METHODS

The programme was developed in a series of structured meetings over a 6-month period. Stakeholders included oral and maxillofacial surgeons, otolaryngologists, anaesthetists, dieticians, physiotherapists, speech and language therapists (SALT) and nursing staff. Based on evidence within current literature and a consensus among the group, an ERAS programme for head and neck surgery patients was formulated. A 12-month study of compliance with the ERAS programme was undertaken from February 2014 to January 2015.

RESULTS

The process has resulted in the realisation of a head and neck ERAS programme. Key elements include a patient diary, nutritional optimisation, avoiding tracheostomy when possible, goal-directed fluid therapy intra-operatively and a specific head and neck postoperative pain management protocol. Overall compliance was high. Important areas showed lower levels of compliance - only 55% of people were given an explanation of the ERAS programme preoperatively, 75% took preoperative carbohydrate drinks, 10% had individualised goal-directed fluid therapy, and 7% were mobilised in the first 24 h after surgery. The mean length of hospital stay was 14.55 days (sd 7.48).

CONCLUSIONS

The ERAS programme developed is now embedded in the care pathway for people undergoing head and neck cancer surgery in our unit. The mean length of hospital stay has reduced since the introduction of the programme.

Contribution of the Leg Club model of care to the well-being of people living with chronic wounds

OBJECTIVE

Social support impacts well-being. Higher levels of social support encourage treatment adherence and aid healing in people living with chronic wounds. The Leg Club model of care harnesses social support mechanisms to improve patient outcomes. This study investigated whether social support mechanisms available through a Leg Club environment influenced well-being.

METHOD

Participants were community Leg Club members. Socio-demographic data was collected, and the Well-being in Wounds Inventory (WOWI) administered to assess 'wound worries,' 'personal resources,' and 'well-being'. Participants' perceived social situation, length of time attending a Leg Club, wound duration, and feelings about their physical appearance were also measured.

RESULTS

The subjects recruited (n=49) were aged between 50 and 94 years (mean=75.34, standard deviation=10.31). Membership of a Leg Club did impact well-being factors. Time spent at a Leg Club improved 'personal resources' over time. 'Perceived social situation' predicted key aspects of well-being, as did 'time spent attending a Leg Club' and 'feelings about physical appearance.' Social support and relief from social isolation were important aspects of Leg Club membership for participants.

CONCLUSION

Attending a Leg Club enhances well-being in people living with a chronic wound; social support has an important role to play in this relationship. Future research should consider the specific interplay of social support mechanisms of Leg Club, and other relevant wound-related variables to optimise patient well-being and treatment outcomes.

DECLARATION OF INTEREST

The Urgo Foundation funded this project. The authors have no conflicts of interest to declare.

4α-phorbol 12,13-didecanoate activates cultured mouse dorsal root ganglia neurons independently of TRPV4

BACKGROUND AND PURPOSE

The Ca(2+) -permeable cation channel TRPV4 is activated by mechanical disturbance of the cell membrane and is implicated in mechanical hyperalgesia. Nerve growth factor (NGF) is increased during inflammation and causes mechanical hyperalgesia. 4α-phorbol 12,13-didecanoate (4αPDD) has been described as a selective TRPV4 agonist. We investigated NGF-induced hyperalgesia in TRPV4 wild-type (+/+) and knockout (-/-) mice, and the increases in [Ca(2+) ](i) produced by 4αPDD in cultured mouse dorsal root ganglia neurons following exposure to NGF.

EXPERIMENTAL APPROACH

Withdrawal thresholds to heat, von Frey hairs and pressure were measured in mice before and after systemic administration of NGF. Changes in intracellular Ca(2+) concentration were measured by ratiometric imaging with Fura-2 in cultured DRG and trigeminal ganglia (TG) neurons during perfusion of TRPV4 agonists.

KEY RESULTS

Administration of NGF caused a significant sensitization to heat and von Frey stimuli in TRPV4 +/+ and -/- mice, but only TRPV4 +/+ mice showed sensitization to noxious pressure. 4αPDD stimulated a dose-dependent increase in [Ca(2+) ](i) in neurons from +/+ and -/- mice, with the proportion of responding neurons and magnitude of increase unaffected by the genotype. In contrast, the selective TRPV4 agonist GSK1016790A failed to stimulate an increase in intracellular Ca(2+) in cultured neurons. Responses to 4αPDD were unaffected by pretreatment with NGF.

CONCLUSIONS AND IMPLICATIONS

TRPV4 contributes to mechanosensation in vivo, but there is little evidence for functional TRPV4 in cultured DRG and TG neurons. We conclude that 4αPDD activates these neurons independently of TRPV4, so it is not appropriate to refer to 4αPDD as a selective TRPV4 agonist.

Computerized cognitive remediation training for schizophrenia: an open label, multi-site, multinational methodology study

A recent single-site study (Fisher et al., 2009. Am J Psychiatry. 166 (7) 805-11) showed that repeated training with the Brain Fitness Program (BFP) improved performance on a battery of neuropsychological tasks. If replicated these data suggest an important non-pharmacological method for ameliorating cognitive impairment in schizophrenia. Our study evaluated the BFP training effects in an open-label, multi-site, multinational clinical trial. Fifty-five stable adult patients with schizophrenia on regular antipsychotic medication completed ≥ 32 BFP training sessions over 8-10 weeks. Training effects on cognitive performance and functional capacity outcome measures were measured using CogState® schizophrenia battery, UCSD Performance based Skills Assessment (UPSA-2) and Cognitive Assessment Interview (CAI). BFP training showed a large and significant treatment effect on a training exercise task (auditory processing speed), however this effect did not generalize to improved performance on independent CogState® assessment. There were no significant effects on UPSA-2 or CAI scores. Our study demonstrated the feasibility of implementing BFP training in a multi-site study. However, BFP training did not show significant treatment effects on cognitive performance or functional capacity outcome measures despite showing large and significant effects on a training exercise.

Atherosclerotic lesions in the thoracic aorta: a South African anatomical and histological mortuary study

BACKGROUND

Worldwide, the prevalence of cardiovascular diseases such as atherosclerosis is on the increase. Younger people may be especially vulnerable owing to their exposure to risk factors such as drug abuse and HIV.

METHODS

The thoracic aortas of 149 South Africans under the age of 50 years were collected at the Salt River Mortuary, Cape Town, and examined macroscopically and microscopically for evidence of anomalies. The sample comprised predominantly males, and included black, coloured and white individuals.

RESULTS

A significantly higher level of macroscopic pathology was found in coloured males, although overall prevalence of pathology in this sample was lower than expected. A positive association was also found between body mass index and vascular pathology in the black and coloured population groups. Microscopic anomalies were common and present at high levels, irrespective of age and racial grouping.

CONCLUSIONS

The widespread prevalence of microscopic anomalies in all groups suggests that these are normal variations that result from haemodynamic forces. The higher prevalence of atherosclerotic lesions in coloured males, however, probably results from specific genetic conditions such as hypercholesterolaemia or lifestyle factors such as diet or tik abuse. The findings suggest that coloured individuals may be at increased risk of developing cardiovascular disease.

THE RELATIONSHIP OF THE AGENT OF HEART-WATER FEVER--RICKETTSIA RUMINANTIUM

Sera from sheep which were infected with heartwater fever from 39 to 110 days before the serum was withdrawn failed to fix complement in the presence of lymphogranuloma venereum antigen.

Do patients require outpatient follow-up after rapid referral double contrast barium enema?

INTRODUCTION

In our hospital, patients above the age of 40 years referred with a change in bowel habit without rectal bleeding undergo a double contrast barium enema (DCBE) ideally within 2 weeks. Results of benign studies are sent to a consultant colorectal surgeon and a routine clinic visit arranged. The aim of this study was to identify whether, following DCBE, patients (i) presented at a later date with colorectal cancer and (ii) needed assessment in clinic.

METHOD

This is a review looking at all patients who underwent DCBE prior to routine clinic visit between January 2004 and December 2005. Hospital databases were cross-referenced to identify any patients presenting with a new diagnosis of colorectal malignancy between DCBE and April 2007. Clinic letters were reviewed to identify the number of outpatient visits prior to discharge and reasons for continued follow-up.

RESULTS

During the study period, 521 patients (age range 31-93 years, 316 female) had DCBE prior to assessment in clinic. Diagnoses: cancer 48 (9.2%), polyps 13 (2.5%), colitis 3 (0.6%), no significant pathology 457 (87.7%). Of this latter cohort, 387 (84.7%) were discharged after one clinic visit; 54 (11.9%) attended twice and 11 (2.4%) were seen more than twice. Reasons for multiple attendances were management of haemorrhoids/anal fissure or investigations of unrelated symptoms. No new cancers were identified in this cohort between January 2004 and April 2007.

CONCLUSION

Double contrast barium enema is a safe screening tool following a '2-week rule' referral with CIBH. Following a report of no significant pathology, there is no need to arrange routine follow-up.

Macular pigment in the human retina: histological evaluation of localization and distribution

PURPOSE

Clinical investigations have demonstrated variation in both the peak optical density and the spatial distribution of macular pigment. To confirm these impressions histologically, the present study examined the distribution of macular pigment in the human retina.

MATERIALS AND METHODS

The macular retina of 11 donor eyes of different ages (28-91 years) were examined histologically on 100 microm vibratome sections directly, without further staining. Measurements were made in two dimensions: (1) adding the number of macular sections with visible macular pigment, and (2) direct measurement of the extension of macular pigment in the foveolar section, which visibly contained the most macular pigment.

RESULTS

The measurements with two methods demonstrated good correlation. The macula demonstrated a variation in the spatial extension of the visible macular pigment between 200 and 900 microm diameter around the centre of the fovea, which was also found when direct measurements were taken. There was no correlation with the donor age. The main location of macular pigment was in the layer of the fibres of Henle in the fovea and in the inner nuclear layer at the parafoveal site.

CONCLUSIONS

Histologically, a wide variation of the spatial distribution of macular pigment was found that confirms clinical observations. The primary localization of human macular pigment is in the inner retinal layers.