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1.
J Plast Reconstr Aesthet Surg ; 75(5): 1644-1652, 2022 05.
Article in English | MEDLINE | ID: mdl-34955401

ABSTRACT

OBJECTIVES: The FACE-Q Skin Cancer module is a patient-reported outcome measure (PROM) for facial skin cancer. It has been anglicised for the UK population and undergone psychometric testing using classical test theory. In this study, further evaluation of construct validity using Rasch measurement theory and hypothesis testing was performed. METHODS: Patients were prospectively recruited to the Patient-Reported Outcome Measures In Skin Cancer Reconstruction (PROMISCR) study and asked to complete the anglicised FACE-Q Skin Cancer module. The scalability and unidimensionality of the data were assessed with a Mokken analysis prior to Rasch analysis. Response thresholds, targeting, fit statistics, local dependency, and internal consistency were examined for all items and subscales. Four a priori hypotheses were tested to evaluate the convergent and divergent validity. We additionally hypothesised that the median 'cancer worry' score would be lower in post-operative than pre-operative patients. RESULTS: 239 patients self-completed the questionnaire between August 2017 and May 2019. Of the ten subscales assessed, five showed relative fit to the Rasch model. Unidimensionality was present for all five subscales, with most demonstrating ordered item thresholds and appropriate fit statistics. Two items in the 'cancer worry' subscale had either disordered or very close response thresholds. Subscales of the FACE-Q Skin Cancer module demonstrated convergent and divergent validity with relevant Skin Cancer Index comparators (p < 0.001). Median 'cancer worry' was lower in post-operative patients (44 vs 39, p < 0.001). CONCLUSION: The anglicised FACE-Q Skin Cancer module shows psychometric validity through hypothesis testing, and both classical and modern test theory.


Subject(s)
Bone Neoplasms , Breast Neoplasms , Facial Neoplasms , Skin Neoplasms , Facial Neoplasms/surgery , Female , Humans , Patient Reported Outcome Measures , Psychometrics , Quality of Life , Reproducibility of Results , Skin Neoplasms/surgery , Surveys and Questionnaires
2.
BJS Open ; 5(4)2021 07 06.
Article in English | MEDLINE | ID: mdl-34323916

ABSTRACT

BACKGROUND: Advances in natural language processing and other machine learning techniques have led to the development of automated agents (chatbots) that mimic human conversation. These systems have mainly been used in commercial settings, and within medicine, for symptom checking and psychotherapy. The aim of this systematic review was to determine the acceptability and implementation success of chatbots in the follow-up of patients who have undergone a physical healthcare intervention. METHODS: A systematic review of MEDLINE, MEDLINE In-process, EMBASE, PsychINFO, CINAHL, CENTRAL and the grey literature using a PRISMA-compliant methodology up to September 2020 was conducted. Abstract screening and data extraction were performed in duplicate. Risk of bias and quality assessments were performed for each study. RESULTS: The search identified 904 studies of which 10 met full inclusion criteria: three randomised control trials, one non-randomised clinical trial and six cohort studies. Chatbots were used for monitoring after the management of cancer, hypertension and asthma, orthopaedic intervention, ureteroscopy and intervention for varicose veins. All chatbots were deployed on mobile devices. A number of metrics were identified and ranged from a 31 per cent chatbot engagement rate to a 97 per cent response rate for system-generated questions. No study examined patient safety. CONCLUSION: A range of chatbot builds and uses was identified. Further investigation of acceptability, efficacy and mechanistic evaluation in outpatient care pathways may lend support to implementation in routine clinical care.


Subject(s)
Communication , Delivery of Health Care , Humans
4.
J Chem Phys ; 153(7): 074105, 2020 Aug 21.
Article in English | MEDLINE | ID: mdl-32828081

ABSTRACT

The authors present a quantity termed charge-spin susceptibility, which measures the charge response to spin degrees of freedom in strongly correlated materials. This quantity is simple to evaluate using both standard density functional theory and many-body electronic structure techniques, enabling comparison between different levels of theory. A benchmark on 28 layered magnetic materials shows that large values of charge-spin susceptibility correlate with unconventional ground states such as disordered magnets and unconventional superconductivity.

7.
Science ; 366(6470)2019 12 06.
Article in English | MEDLINE | ID: mdl-31806787

ABSTRACT

Hesselmann et al question one of our conclusions: the suppression of Fermi velocity at the Gross-Neveu critical point for the specific case of vanishing long-range interactions and at zero energy. The possibility they raise could occur in any finite-size extrapolation of numerical data. Although we cannot definitively rule out this possibility, we provide mathematical bounds on its likelihood.


Subject(s)
Electrons , Role
9.
Br J Dermatol ; 180(5): 976, 2019 05.
Article in English | MEDLINE | ID: mdl-31025730
10.
Science ; 361(6402): 570-574, 2018 08 10.
Article in English | MEDLINE | ID: mdl-30093594

ABSTRACT

The role of electron-electron interactions in two-dimensional Dirac fermion systems remains enigmatic. Using a combination of nonperturbative numerical and analytical techniques that incorporate both the contact and long-range parts of the Coulomb interaction, we identify the two previously discussed regimes: a Gross-Neveu transition to a strongly correlated Mott insulator and a semimetallic state with a logarithmically diverging Fermi velocity accurately described by the random phase approximation. We predict that experimental realizations of Dirac fermions span this crossover and that this determines whether the Fermi velocity is increased or decreased by interactions. We explain several long-standing mysteries, including why the observed Fermi velocity in graphene is consistently about 20% larger than values obtained from ab initio calculations and why graphene on different substrates shows different behaviors.

11.
Nat Nanotechnol ; 13(9): 828-834, 2018 09.
Article in English | MEDLINE | ID: mdl-29941889

ABSTRACT

Spatially tailored pseudo-magnetic fields (PMFs) can give rise to pseudo-Landau levels and the valley Hall effect in graphene. At an experimental level, it is highly challenging to create the specific strain texture that can generate PMFs over large areas. Here, we report that superposing graphene on multilayer black phosphorus creates shear-strained superlattices that generate a PMF over an entire graphene-black phosphorus heterostructure with edge size of tens of micrometres. The PMF is intertwined with the spatial period of the moiré pattern, and its spatial distribution and intensity can be modified by changing the relative orientation of the two materials. We show that the emerging pseudo-Landau levels influence the transport properties of graphene-black phosphorus field-effect transistor devices with Hall bar geometry. The application of an external magnetic field allows us to enhance or reduce the effective field depending on the valley polarization with the prospect of developing a valley filter.

13.
J Hand Surg Eur Vol ; 42(3): 301-309, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27872343

ABSTRACT

This prospective cohort study investigated the responsiveness and interpretability of the Disabilities of the Arm, Shoulder and Hand (DASH) and Unité Rhumatologique des Affections de la Main (URAM) outcome measures for assessing recovery after fasciectomy and dermofasciectomy for Dupuytren's disease. DASH outcome scores at 1 year were significantly better than at 6 weeks, suggesting that recovery is not complete by 6 weeks. Of the 101 patients recruited to the DASH cohort, 71 completed preoperative, 6 week and 1 year postoperative DASH scores; 68 of them completed preoperative and 1 year postoperative DASH scores and an external anchor question. In the URAM cohort, 30/44 completed the preoperative and the 1 year postoperative URAM scores and the anchor question. The DASH score exhibited moderate responsiveness but poor interpretability on receiver operating characteristic curve analysis, such that a minimal important change could not be estimated. The URAM score showed acceptable responsiveness, and an MIC of 10.5 on receiver operating characteristic analysis. LEVEL OF EVIDENCE: II.


Subject(s)
Dupuytren Contracture/surgery , Patient Reported Outcome Measures , Adult , Aged , Aged, 80 and over , Fasciotomy , Female , Humans , Male , Middle Aged , Prospective Studies , Recovery of Function , Sensitivity and Specificity , Surveys and Questionnaires
14.
J Hand Surg Eur Vol ; 42(1): 7-17, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27474501

ABSTRACT

Variables associated with recurrent Dupuytren's disease, or a 'diathesis', have been investigated, but those associated with functional outcome and complications are less well studied. Outcomes 1 or 5 years after an aponeurotomy, fasciectomy or dermofasciectomy were assessed by patient interview and examination at five UK centres. A total of 432 procedures were studied. The reoperation rate did not differ at 1 year ( p = 0.396, Chi-square test with Monte Carlo simulation), but was higher after aponeurotomy in the 5-year group (30%, versus 6% after fasciectomy and 0% after dermofasciectomy, p = 0.003, Chi square test with Monte Carlo simulation). Loss of function (DASH>15) did not differ between procedures at 5 years, even when reoperation and other variables were controlled. Diabetes, female gender and previous ipsilateral surgery were associated with poorer function in logistic regression analysis. The variables associated with poor function after treatments differ from diathesis variables. Aponeurotomy had lower complication rates than fasciectomy and dermofasciectomy. This may counterbalance the former's higher recurrence rate and explain why aponeurotomy demonstrated similar long-term functional outcome compared with excisional surgery in this study. LEVEL OF EVIDENCE: III.

15.
Eur J Orthop Surg Traumatol ; 27(2): 267-272, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27928639

ABSTRACT

Proximal femoral fractures in adults under 50 years are not as common as in the elderly, but may have just as significant an impact. There is little in the literature describing the functional outcomes of fixation in this age group. Our aim was to assess the clinical and functional outcomes of operative management of extracapsular proximal femoral fractures (AO 31-A) in the young adult (<50 years). Consecutive skeletally mature patients <50 years undergoing operative fixation of these fractures were obtained from a prospective database over a 12-year period. Complications and mortality data were obtained from this database and case note review. Outcome scores were obtained via postal questionnaires. Eighty-eight patients were included in the study of which 74 (84%) had fixation with the dynamic hip screw. The mean age was 39 years (range 17-50) with a male preponderance (73.8%). Mean hospital stay was 14 days (range 2-94). Seventeen (19.3%) patients had died at a mean of 40 months from their operation date. The 1-year mortality was 4.5%. There were five complications (5.7%). SF-36 and EuroQol 5D scores showed that 5-10% had severe problems with a 20% decrease in quality of life compared to population norms. The biggest differences were in the physical function modalities. One-third had fair to poor hip function as assessed by the Oxford Hip Score. Though these injuries are relatively rare in this age group, they do have significant mortality and functional impairment reflecting a higher energy of injury rather than the frailty seen in the elderly.


Subject(s)
Fracture Fixation, Internal/methods , Hip Fractures/surgery , Adolescent , Adult , Bone Screws , England/epidemiology , Exercise/physiology , Female , Fracture Fixation, Internal/mortality , Fracture Fixation, Internal/statistics & numerical data , Health Status , Hip Fractures/mortality , Humans , Length of Stay , Male , Middle Aged , Prospective Studies , Quality of Life , Treatment Outcome , Young Adult
16.
J Plast Reconstr Aesthet Surg ; 69(10): 1424-9, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27395424

ABSTRACT

Diagnosis of wrist pain can be difficult to determine with clinical examination and conventional imaging techniques alone. Bone SPECT-CT (single-photon emission tomography with computerized tomography) is a hybrid imaging technique that overlays functional bone scintigraphy in tomographic/3D mode with conventional CT. Data from the two modalities are complementary; areas of abnormal bone metabolism can be localized with anatomical precision, hitherto lacking in conventional bone scans, while structural information from the CT scan further embellishes the diagnostic information. Over the last 6 years, one surgeon (David Evans) has used bone SPECT and later bone SPECT-CT as an additional line of investigation. This is a series of 21 consecutive patients with wrist pain that could not be diagnostically resolved with the usual combination of history, examination, and conventional imaging, and therefore underwent bone SPECT-CT. Clinical and imaging findings, management, and outcomes of these cases are discussed to explore the potential role of this hybrid functional modality in hand and wrist surgical practice.


Subject(s)
Carpal Bones/diagnostic imaging , Pain , Single Photon Emission Computed Tomography Computed Tomography , Wrist , Adult , Female , Humans , Male , Pain/diagnosis , Pain/physiopathology , Reproducibility of Results , Single Photon Emission Computed Tomography Computed Tomography/instrumentation , Single Photon Emission Computed Tomography Computed Tomography/methods , Wrist/diagnostic imaging , Wrist/physiopathology
17.
Phys Rev Lett ; 115(18): 186602, 2015 Oct 30.
Article in English | MEDLINE | ID: mdl-26565484

ABSTRACT

The question of whether electron-electron interactions can drive a metal to insulator transition in graphene under realistic experimental conditions is addressed. Using three representative methods to calculate the effective long-range Coulomb interaction between π electrons in graphene and solving for the ground state using quantum Monte Carlo methods, we argue that, without strain, graphene remains metallic and changing the substrate from SiO_{2} to suspended samples hardly makes any difference. In contrast, applying a rather large-but experimentally realistic-uniform and isotropic strain of about 15% seems to be a promising route to making graphene an antiferromagnetic Mott insulator.

19.
Sci Rep ; 5: 11430, 2015 Jun 23.
Article in English | MEDLINE | ID: mdl-26100970

ABSTRACT

Magnetic materials have found wide application ranging from electronics and memories to medicine. Essential to these advances is the control of the magnetic order. To date, most room-temperature applications have a fixed magnetic moment whose orientation is manipulated for functionality. Here we demonstrate an iron-oxide and graphene oxide nanocomposite based device that acts as a tunable ferromagnet at room temperature. Not only can we tune its transition temperature in a wide range of temperatures around room temperature, but the magnetization can also be tuned from zero to 0.011 A m(2)/kg through an initialization process with two readily accessible knobs (magnetic field and electric current), after which the system retains its magnetic properties semi-permanently until the next initialization process. We construct a theoretical model to illustrate that this tunability originates from an indirect exchange interaction mediated by spin-imbalanced electrons inside the nanocomposite.

20.
Eur J Orthop Surg Traumatol ; 25(3): 471-6, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25331168

ABSTRACT

This study aimed to evaluate the effect of manipulation under anaesthesia (MUA) and Kirschner wire (K-wire) fixation of displaced, paediatric distal radius fractures on residual radiological angulation, displacement, and shortening, as well as functional outcomes, including complication rates. A retrospective review was conducted of all paediatric patients undergoing MUA and K-wire fixation for an extra-articular distal radius fracture over a period of 5 years. A total of 248 patients were included in the study with a mean age of 9.9 years (3-15). Mean follow-up was 6.6 weeks (4-156). There was a statistically significant increase in median dorsal angulation (p<0.0001) between initial post-operative and follow-up radiographs at the time of K-wire removal. The number of K-wires used did not have a significant effect on dorsal angulation (p=0.9015) at time of K-wire removal, nor did the use of an above or below elbow cast (p=0.3883). Seventeen patients required a further general anaesthetic (5 revision operations, 12 removal of migrated K-wires). Eighty-seven percentage of (215 patients) of patients had normal function at follow-up post-K-wire removal. Angulation at time of K-wire removal of more than 15° was significantly associated with reduced functional outcome (p=0.0377). A total of 41 patients (17%) had complications associated with K-wire use. We conclude that though K-wire fixation is an effective technique, it does not prevent re-angulation of the fracture and is associated with a significant complication rate. Given the remodelling potential and tolerance to deformity in children, surgeons should give careful thought before utilising this technique for all displaced or angulated paediatric distal radius fractures. If used, 1 K-wire with immobilisation in a below elbow cast is sufficient in most cases.


Subject(s)
Bone Wires , Fracture Fixation, Internal , Manipulation, Orthopedic , Radius Fractures/surgery , Adolescent , Anesthesia, General , Bone Wires/adverse effects , Casts, Surgical , Child , Child, Preschool , Female , Fracture Fixation, Internal/adverse effects , Fracture Fixation, Internal/instrumentation , Humans , Male , Radiography , Radius Fractures/diagnostic imaging , Radius Fractures/physiopathology , Recovery of Function , Reoperation , Retrospective Studies , Treatment Outcome
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