Artificial intelligence and surgical innovation: lower limb arthroplasty.

The number of patients requiring hip and knee arthroplasty continues to rise each year. Patients are living longer and expecting to remain active into later life following joint replacement. Developments in computer-assisted surgery and robotic technology may optimise surgical outcomes and patient satisfaction following lower limb arthroplasty. The use of artificial intelligence in healthcare is rapidly growing and has gained momentum in lower limb arthroplasty. This article reviews the use of artificial intelligence and surgical innovation in lower limb arthroplasty, with a particular focus on robotic-assisted surgery in total knee arthroplasty.

Paediatric antimicrobial stewardship programmes in the UK's regional children's hospitals.

A survey was conducted in UK regional children's hospitals with paediatric intensive care and paediatric infectious disease (PID) departments to describe the characteristics of paediatric antimicrobial stewardship (PAS) programmes. A structured questionnaire was sent to PAS coordinators. 'Audit and feedback' was implemented in 13 out of 17 centres. Microbiology-led services were more likely to implement antimicrobial restriction (75% vs 33% in PID-led services), to focus on broad-spectrum antibiotics, and to review patients with positive blood cultures. PID-led services were more likely to identify patients from e-prescribing or drug charts and review all antimicrobials. A PAS network has been established.

Mechano-chemical manipulation of Sn chains on Si(1 0 0) by NC-AFM.

We investigate the atomic structure of Sn dimer chains grown on the Si(1 0 0) surface using non-contact atomic force microscopy (NC-AFM) at cryogenic temperatures. We find that similar to the native Si(1 0 0) dimer structure, the ground state of the Sn dimer structure is buckled at low temperature. At 5 K we show that the buckling state of the Sn dimers may be controllably, and reversibly, manipulated with atomic precision by close approach of the tip, without modification of the underlying substrate buckling structure. At intermediate cryogenic temperatures we observe changes in the configuration of the dimer chains in the region where the tip-sample interaction is very weak, suggesting that the energy barrier to transit between configurations is sufficiently small to be surmounted at 78 K.

Epidemiological, clinical and genetic aspects of adult onset isolated focal dystonia in Ireland.

BACKGROUND: Adult onset idiopathic isolated focal dystonia presents with a number of phenotypes. Reported prevalence rates vary considerably; well-characterized cohorts are important to our understanding of this disorder. AIM: To perform a nationwide epidemiological study of adult onset idiopathic isolated focal dystonia in the Republic of Ireland. METHODS: Patients with adult onset idiopathic isolated focal dystonia were recruited from multiple sources. Diagnosis was based on assessment by a neurologist with an expertise in movement disorders. When consent was obtained, a number of clinical features including family history were assessed. RESULTS: On the prevalence date there were 592 individuals in Ireland with adult onset idiopathic isolated focal dystonia, a point prevalence of 17.8 per 100 000 (95% confidence interval 16.4-19.2). Phenotype numbers were cervical dystonia 410 (69.2%), blepharospasm 102 (17.2%), focal hand dystonia 39 (6.6%), spasmodic dysphonia 18 (3.0%), musician's dystonia 17 (2.9%) and oromandibular dystonia six (1.0%). Sixty-two (16.5%) of 375 consenting index cases had a relative with clinically confirmed adult onset idiopathic isolated focal dystonia (18 multiplex and 24 duplex families). Marked variations in the proportions of patients with tremor, segmental spread, sensory tricks, pain and psychiatric symptoms by phenotype were documented. CONCLUSIONS: The prevalence of adult onset idiopathic isolated focal dystonia in Ireland is higher than that recorded in many similar service-based epidemiological studies but is still likely to be an underestimate. The low proportion of individuals with blepharospasm may reflect reduced environmental exposure to sunlight in Ireland. This study will serve as a resource for international comparative studies of environmental and genetic factors in the pathogenesis of the disorder.

Mohs micrographic surgery for periocular skin tumours in Ireland.

OBJECTIVE: To describe the shared care and outcomes of patients with periocular skin tumours who underwent Mohs micrographic surgery (MMS) performed by dermatologists, followed by oculoplastic reconstruction undertaken by ophthalmologists at two teaching and one private hospital in Ireland. RESEARCH DESIGN AND METHODS: This was a retrospective chart review at the Royal Victoria Eye and Ear Hospital, St James Hospital and the Hermitage Clinic. RESULTS: One hundred and twenty seven patients had periocular Mohs surgery between November 2006 and January 2013 mainly indicated for basal cell carcinoma. The mean follow-up time was 2 years and to date there have been no local recurrences. CONCLUSIONS: MMS is available in Ireland and should be considered for patients with facial tumours in the ocular region.

Measuring the mechanical properties of molecular conformers.

Scanning probe-actuated single molecule manipulation has proven to be an exceptionally powerful tool for the systematic atomic-scale interrogation of molecular adsorbates. To date, however, the extent to which molecular conformation affects the force required to push or pull a single molecule has not been explored. Here we probe the mechanochemical response of two tetra(4-bromophenyl)porphyrin conformers using non-contact atomic force microscopy where we find a large difference between the lateral forces required for manipulation. Remarkably, despite sharing very similar adsorption characteristics, variations in the potential energy surface are capable of prohibiting probe-induced positioning of one conformer, while simultaneously permitting manipulation of the alternative conformational form. Our results are interpreted in the context of dispersion-corrected density functional theory calculations which reveal significant differences in the diffusion barriers for each conformer. These results demonstrate that conformational variation significantly modifies the mechanical response of even simple porpyhrins, potentially affecting many other flexible molecules.

Effects of lipoprotein apheresis on PCSK9 levels.

BACKGROUND: PCSK9 (Proprotein Convertase Subtilisin/Kexin Type 9) increases LDL cholesterol (LDL-C) levels by stimulating the degradation of Low Density Lipoprotein receptors (LDL-r). This protein is now of high interest because antibodies which inhibit its effect on LDL-r are being developed. A severe hypercholesterolemia and / or an elevation of lipoprotein(a) can be treated with lipoprotein apheresis (LA) in high-risk patients. METHODS: We measured serum PCSK9 levels in patients eligible for the extracorporeal treatment: in 40 patients (Cohort I) who were treated with different systems before and after apheresis sessions and in the intervals between sessions. 10 patients (Cohort II) who were eligible but did not start LA yet served as controls. RESULTS: Patients' baseline serum PCSK9 levels were elevated relative to healthy volunteers and LA sessions acutely reduced the mean PCSK9 concentrations by 51%. Comparison of the effectiveness of the different LA methods demonstrated the DSA and HELP were more effective than the DALI system. After 24 h PCSK9 levels had returned to baseline compared to 8 days for the LDL-C concentrations to return to its pre-apheresis levels. In Cohort II baseline PCSK9 levels were similar to those in Cohort I. CONCLUSION: The acute reductions of PCSK9 by apheresis may be beneficial with respect to increasing the effectiveness of lipid-lowering drugs and with respect to an anti-atherosclerotic effect. In the future, antagonists to PCSK9 will probably be combined with or possibly replace LA in patients with a very high cardiovascular risk.

First on-line survey of an international multidisciplinary working group (MightyMedic) on current practice in diagnosis, therapy and follow-up of dyslipidemias.

The MightyMedic (Multidisciplinary International Group for Hemapheresis TherapY and MEtabolic DIsturbances Contrast) Working Group has been founded in 2013. The leading idea was to establish an international network of interdisciplinary nature aimed at working to cross national borders research projects, clinical trials, educational initiatives (meetings, workshops, summer schools) in the field of metabolic diseases, namely hyperlipidemias, and diabetes, preventive cardiology, and atherosclerosis. Therapeutic apheresis, its indications and techniques, is a parallel field of investigation. The first on-line survey of the Group has been completed in the first half of 2014. The survey included # 24 Centers in Italy, Germany, Greece, UK, Sweden, Japan and USA. Relevant data have been collected on current practice in diagnosis, therapy and follow-up of dyslipidemias. 240 subjects with hyperlipidemia and treated with lipoprotein apheresis have been reported in the survey, but a large percentage of patients (35%) who could benefit from this therapeutic option are still treated by conventional drug approach. Genetic molecular diagnosis is performed in only 33% of patients while Lipoprotein(a) (Lp(a)) is included in cardiovascular disease risk assessment in 71% of participating Centers. New detailed investigations and prospective multicenter studies are needed to evaluate changes induced by the impact of updated indications and strategies, as well as new treatment options, targeting standardization of therapeutic and diagnostic approaches.

An evaluation of the relationship between Enterobius vermicularis infestation and acute appendicitis in a paediatric population--A retrospective cohort study.

BACKGROUND: Enterobius vermicularis is an often unexpected finding in appendectomy specimen, most commonly seen in paediatric cases. Predicting the presence of E. vermicularis in the setting of appendectomy is important to avoid unnecessary appendectomy and associated morbidity. We sought to identify the incidence of E. vermicularis in a paediatric population undergoing appendectomy for clinically suspected acute appendicitis and identify predictive factors for E. vermicularis. METHODS: This study was performed in an 800-bed University Teaching Hospital, in the Republic of Ireland. We identified all paediatric appendectomies performed at our institute from January to December 2012 using prospectively maintained operating theatre logbooks. In-hospital Histopathology database, medical notes and operative findings were reviewed for each patient and relevant data recorded. Statistical analysis was performed using IBM SPSS, version 21. RESULTS: In total 182 paediatric appendectomies were performed during the year 2012 for clinically suspected acute appendicitis. Demographics included: Mean age 11.14 years (3-16), gender 1M: 1F. 58.8% of procedures were completed laparoscopically, 39% open and 2.2% were converted. The negative appendectomy rate was 22.5%. The annual incidence of E. vermicularis in acute appendicitis specimen from a paediatric cohort at our institute was 7% (1 in 14). In specimen containing E. vermicularis, 69% had no evidence of appendicitis and of those that had, no gangrene or perforation was seen. The presence of E. vermicularis in paediatric patients with RIF pain may be predicted by Eosinophilia (p = 0.016), normal WCC (p = 0.034) and normal Neutrophil count (p = 0.014). CONCLUSIONS: E. vermicularis is responsible for 7% of acute appendicitis. It is responsible for a significantly higher negative appendectomy rate which if predicted may avoid unnecessary appendectomy and associated morbidity.

Simulated structure and imaging of NTCDI on Si(1 1 1)-7 × 7 : a combined STM, NC-AFM and DFT study.

The adsorption of naphthalene tetracarboxylic diimide (NTCDI) on Si(1 1 1)-7 × 7 is investigated through a combination of scanning tunnelling microscopy (STM), noncontact atomic force microscopy (NC-AFM) and density functional theory (DFT) calculations. We show that NTCDI adopts multiple planar adsorption geometries on the Si(1 1 1)-7 × 7 surface which can be imaged with intramolecular bond resolution using NC-AFM. DFT calculations reveal adsorption is dominated by covalent bond formation between the molecular oxygen atoms and the surface silicon adatoms. The chemisorption of the molecule is found to induce subtle distortions to the molecular structure, which are observed in NC-AFM images.

Mapping the force field of a hydrogen-bonded assembly.

Hydrogen bonding underpins the properties of a vast array of systems spanning a wide variety of scientific fields. From the elegance of base pair interactions in DNA to the symmetry of extended supramolecular assemblies, hydrogen bonds play an essential role in directing intermolecular forces. Yet fundamental aspects of the hydrogen bond continue to be vigorously debated. Here we use dynamic force microscopy (DFM) to quantitatively map the tip-sample force field for naphthalene tetracarboxylic diimide molecules hydrogen-bonded in two-dimensional assemblies. A comparison of experimental images and force spectra with their simulated counterparts shows that intermolecular contrast arises from repulsive tip-sample interactions whose interpretation can be aided via an examination of charge density depletion across the molecular system. Interpreting DFM images of hydrogen-bonded systems therefore necessitates detailed consideration of the coupled tip-molecule system: analyses based on intermolecular charge density in the absence of the tip fail to capture the essential physical chemistry underpinning the imaging mechanism.

Precise orientation of a single C60 molecule on the tip of a scanning probe microscope.

We show that the precise orientation of a C(60) molecule which terminates the tip of a scanning probe microscope can be determined with atomic precision from submolecular contrast images of the fullerene cage. A comparison of experimental scanning tunneling microscopy data with images simulated using computationally inexpensive Hückel theory provides a robust method of identifying molecular rotation and tilt at the end of the probe microscope tip. Noncontact atomic force microscopy resolves the atoms of the C(60) cage closest to the surface for a range of molecular orientations at tip-sample separations where the molecule-substrate interaction potential is weakly attractive. Measurements of the C(60)-C(60) pair potential acquired using a fullerene-terminated tip are in excellent agreement with theoretical predictions based on a pairwise summation of the van der Waals interactions between C atoms in each cage, i.e., the Girifalco potential [L. Girifalco, J. Phys. Chem. 95, 5370 (1991)].

Imaging and manipulation of the Si(100) surface by small-amplitude NC-AFM at zero and very low applied bias.

We use a noncontact atomic force microscope in the qPlus configuration to investigate the structure and influence of defects on the Si(100) surface. By applying millivolt biases, simultaneous tunnel current data is acquired, providing information about the electronic properties of the surface at biases often inaccessible during conventional STM imaging, and highlighting the difference between the contrast observed in NC-AFM and tunnel current images. We also show how NC-AFM (in the absence of tunnel current) can be used to manipulate both the clean c(4 × 2) surface and dopant-related defects.

Radio imaging of the very-high-energy gamma-ray emission region in the central engine of a radio galaxy.

The accretion of matter onto a massive black hole is believed to feed the relativistic plasma jets found in many active galactic nuclei (AGN). Although some AGN accelerate particles to energies exceeding 10(12) electron volts and are bright sources of very-high-energy (VHE) gamma-ray emission, it is not yet known where the VHE emission originates. Here we report on radio and VHE observations of the radio galaxy Messier 87, revealing a period of extremely strong VHE gamma-ray flares accompanied by a strong increase of the radio flux from its nucleus. These results imply that charged particles are accelerated to very high energies in the immediate vicinity of the black hole.

Modelling approaches to the dewetting of evaporating thin films of nanoparticle suspensions.

We review recent experiments on dewetting thin films of evaporating colloidal nanoparticle suspensions (nanofluids) and discuss several theoretical approaches to describe the ongoing processes including coupled transport and phase changes. These approaches range from microscopic discrete stochastic theories to mesoscopic continuous deterministic descriptions. In particular, we describe (i) a microscopic kinetic Monte Carlo model, (ii) a dynamical density functional theory and (iii) a hydrodynamic thin film model. Models (i) and (ii) are employed to discuss the formation of polygonal networks, spinodal and branched structures resulting from the dewetting of an ultrathin 'postcursor film' that remains behind a mesoscopic dewetting front. We highlight, in particular, the presence of a transverse instability in the evaporative dewetting front, which results in highly branched fingering structures. The subtle interplay of decomposition in the film and contact line motion is discussed. Finally, we discuss a simple thin film model (iii) of the hydrodynamics on the mesoscale. We employ coupled evolution equations for the film thickness profile and mean particle concentration. The model is used to discuss the self-pinning and depinning of a contact line related to the 'coffee-stain' effect. In the course of the review we discuss the advantages and limitations of the different theories, as well as possible future developments and extensions.

Front instabilities in evaporatively dewetting nanofluids.

Various experimental settings that involve drying solutions or suspensions of nanoparticles-often called nanofluids-have recently been used to produce structured nanoparticle layers. In addition to the formation of polygonal networks and spinodal-like patterns, the occurrence of branched structures has been reported. After reviewing the experimental results we use a modified version of the Monte Carlo model first introduced by Rabani [Nature 426, 271 (2003)] to study structure formation in evaporating films of nanoparticle solutions for the case that all structuring is driven by the interplay of evaporating solvent and diffusing nanoparticles. After introducing the model and its general behavior we focus on receding dewetting fronts which are initially straight but develop a transverse fingering instability. We analyze the dependence of the characteristics of the resulting branching patterns on the driving effective chemical potential, the mobility and concentration of the nanoparticles, and the interaction strength between liquid and nanoparticles. This allows us to understand the underlying instability mechanism.

Fingering instabilities in dewetting nanofluids.

The growth of fingering patterns in dewetting nanofluids (colloidal solutions of thiol-passivated gold nanoparticles) has been followed in real time using contrast-enhanced video microscopy. The fingering instability on which we focus here arises from evaporatively driven nucleation and growth in a nanoscopically thin precursor solvent film behind the macroscopic contact line. We find that well-developed isotropic fingering structures only form for a narrow range of experimental parameters. Numerical simulations, based on a modification of the Monte Carlo approach introduced by Rabani et al. [Nature (London) 426, 271 (2003)10.1038/nature02087], reproduce the patterns we observe experimentally.

The use of infliximab in ocular inflammation.

AIMS: Experience with anti-tumour necrosis factor alpha medications in ophthalmology has been mainly in the treatment of resistant uveitis and scleritis. There have been a few case reports and one case series detailing the use of infliximab in the treatment of orbital inflammatory disease, but there is still limited experience with these agents in a variety of orbital inflammatory conditions. We describe successful suppression of inflammation with infliximab in the Idiopathic orbital inflammation, thyroid associated orbital inflammation and chronic relapsing inflammatory optic neuropathy. METHODS: This is a retrospective observational case series of five cases of orbital and ocular inflammation. RESULTS: We describe effects of infliximab in the treatment of three cases of orbital inflammation and two cases of chronic relapsing inflammatory optic neuropathy, all of which were unresponsive to alternative immune modulators. The patients received relief of symptoms and signs of inflammation in all five cases. However, this relief was not absolute as symptoms returned around week 5 post-inflammation. CONCLUSION: This report highlights the expanding role of the biological agents in ophthalmology. Although not the answer in treatment, they offer a valuable alternative to steroids in cases of refractory inflammation.

Resonant processes and Coulomb interactions in (C59N)2.

We have determined the on-site molecular Coulomb interaction energy U of a (C59N)2 bulk film and find values ranging from 1.10+/-0.10 eV for the highest occupied molecular orbital to 1.35+/-0.10 eV for the deeper lying orbitals, comparable to values found in C60. The on-site Coulomb interaction between a carbon core hole and valence electrons, Uc, is, however, substantially lower than in C60 at 1.35+/-0.07 eV. Resonant photoemission (RESPES) results show a weakened participator decay channel, especially around the N 1s threshold, where resonance of the highest occupied molecular orbital shoulder is absent. Near-edge x-ray absorption fine structure and constant initial state measurements, taken in parallel with the RESPES data, indicate, however, that matrix element effects cannot be ruled out.