The accuracy of three-dimensional prediction of soft tissue changes following the surgical correction of facial asymmetry: an innovative concept

The accuracy of three-dimensional (3D) predictions of soft tissue changes in the surgical correction of facial asymmetry was evaluated in this study. Preoperative (T1) and 6–12-month postoperative (T2) cone beam computed tomography scans of 13 patients were studied. All patients underwent surgical correction of facial asymmetry as part of a multidisciplinary treatment protocol. The magnitude of the surgical movement was measured; virtual surgery was performed on the preoperative scans using Maxilim software. The predicted soft tissue changes were compared to the actual postoperative appearance (T2). Mean (signed) distances and mean (absolute) distances between the predicted and actual 3D surface meshes for each region were calculated. The one-sample t-test was applied to test the alternative hypothesis that the mean absolute distances had a value of <2.0 mm. A novel directional analysis was applied to analyse the accuracy of the prediction of soft tissue changes. The results showed that the distances between the predicted and actual postoperative soft tissue changes were less than 2.0 mm in all regions. The predicted facial morphology was narrower than the actual surgical changes in the cheek regions. 3D soft tissue prediction using Maxilim software in patients undergoing the correction of facial asymmetry is clinically acceptable

Analysis of Reinforced Concrete Columns Subjected to Combined Axial, Flexure, Shear, and Torsional Loads

This paper describes the implementation of a 3-dimensional concrete constitutive model for fiber-based analysis of reinforced concrete members subjected to combined loadings including torsion. The proposed model is formulated to address the interaction between the axial force, bidirectional shear, biaxial bending, and torsion. The shear mechanism along the beam is modeled using a Timoshenko beam approach with three dimensional (3-D) frame elements with arbitrary cross-section geometry. The model considers the 3D equilibrium, compatibility, and constitutive laws of materials at the section and structural level. The concrete constitutive law follows the Softened Membrane Model (SMM) with a tangent-stiffness formulation. The emphasis of the paper is on evaluation of the effect of the different stress states on the global and local behavior of the member. The ability of the model to assess the ultimate strength, stiffness, energy dissipation, failure modes under 3-dimensional loading is evaluated by correlation of analytical results with experimental tests of RC specimens

Non-linear analysis of reinforced concrete walls under three-dimensional loading

Analytical studies are conducted to develop an effective analytical model to simulate the non-linear response of reinforced concrete (RC) walls subjected to three-dimensional (3D) loads. The interaction between the concrete and steel is taken into account with consideration of the smeared behaviour of steel and tension stiffening of concrete. The proposed model is formulated to address the interaction between the axial force, shear, bending and torsion loads. The shear mechanism along the beam is modelled by adopting a Timoshenko beam approach for 3D frame elements with arbitrary cross-section geometry. The non-linear behaviour of the composite element is derived entirely from the constitutive laws of concrete and steel. The concrete constitutive model follows the softened membrane model that predicts the tensile cracking, compression crushing, strain softening, steel yielding and material damage under combined loadings. The validity of the model is established through a correlation study of experimentally tested RC shear walls subjected to monotonic loading conditions

Earth-like sand fluxes on Mars

Strong and sustained winds on Mars have been considered rare, on the basis of surface meteorology measurements and global circulation models, raising the question of whether the abundant dunes and evidence for wind erosion seen on the planet are a current process. Recent studies showed sand activity, but could not determine whether entire dunes were moving—implying large sand fluxes—or whether more localized and surficial changes had occurred. Here we present measurements of the migration rate of sand ripples and dune lee fronts at the Nili Patera dune field. We show that the dunes are near steady state, with their entire volumes composed of mobile sand. The dunes have unexpectedly high sand fluxes, similar, for example, to those in Victoria Valley, Antarctica, implying that rates of landscape modification on Mars and Earth are similar

Early detection of Aspergillus carbonarius and A. niger on table grapes: a tool for quality improvement

Aspergillus carbonarius and A. niger aggregate are the main fungal contaminants of table grapes. Besides their ability to cause black rot, they can produce ochratoxin A (OTA), a mycotoxin that has attracted increasing attention worldwide. The objective of this work was to set up a simple and rapid molecular method for the early detection of both fungi in table grapes before fungal development becomes evident. Polymerase chain reaction (PCR)-based assays were developed by designing species-specific primers based on the polyketide synthases (PKSS) sequences of A. carbonarius and A. niger that have recently been demonstrated to be involved in OTA biosynthesis. Three table grape varieties (Red globe, Crimson seedless, and Italia) were inoculated with A. carbonarius and A. niger aggregate strains producing OTA. The extracted DNA from control (non-inoculated) and inoculated grapes was amplified by PCR using ACPKS2F-ACPKS2R for A. carbonarius and ANPKS5-ANPKS6 for A. niger aggregate. Both primers allowed a clear detection, even in symptomless samples. PCR-based methods are considered to be a good alternative to traditional diagnostic means for the early detection of fungi in complex matrix for their high specificity and sensitivity. The results obtained could be useful for the definition of a 'quality label' for tested grapes to improve the safety measures taken to guarantee the production of fresh table grapes

Health economic burden that wounds impose on the National Health Service in the UK

OBJECTIVE: To estimate the prevalence of wounds managed by the UK's National Health Service (NHS) in 2012/2013 and the annual levels of healthcare resource use attributable to their management and corresponding costs. METHODS: This was a retrospective cohort analysis of the records of patients in The Health Improvement Network (THIN) Database. Records of 1000 adult patients who had a wound in 2012/2013 (cases) were randomly selected and matched with 1000 patients with no history of a wound (controls). Patients' characteristics, wound-related health outcomes and all healthcare resource use were quantified and the total NHS cost of patient management was estimated at 2013/2014 prices. RESULTS: Patients' mean age was 69.0 years and 45% were male. 76% of patients presented with a new wound in the study year and 61% of wounds healed during the study year. Nutritional deficiency (OR 0.53; p<0.001) and diabetes (OR 0.65; p<0.001) were independent risk factors for non-healing. There were an estimated 2.2 million wounds managed by the NHS in 2012/2013. Annual levels of resource use attributable to managing these wounds and associated comorbidities included 18.6 million practice nurse visits, 10.9 million community nurse visits, 7.7 million GP visits and 3.4 million hospital outpatient visits. The annual NHS cost of managing these wounds and associated comorbidities was pound5.3 billion. This was reduced to between pound5.1 and pound4.5 billion after adjusting for comorbidities. CONCLUSIONS: Real world evidence highlights wound management is predominantly a nurse-led discipline. Approximately 30% of wounds lacked a differential diagnosis, indicative of practical difficulties experienced by non-specialist clinicians. Wounds impose a substantial health economic burden on the UK's NHS, comparable to that of managing obesity ( pound5.0 billion). Clinical and economic benefits could accrue from improved systems of care and an increased awareness of the impact that wounds impose on patients and the NHS.Ye

Towards Assurance for Plug & Play Medical Systems

Traditional safety-critical systems are designed and integrated by a systems integrator. The system integrator can asses the safety of the completed system before it is deployed. In medicine, there is a desire to transition from the traditional approach to a new model wherein a user can combine various devices post-hoc to create a new composite system that addresses a specific clinical scenario. Ensuring the safety of these systems is challenging: Safety is a property of systems that arises from the interaction of system components and it’s not possible to asses overall system safety by assessing a single component in isolation. It is unlikely that end-users will have the engineering expertise or resources to perform safety assessments each time they create a new composite system. In this paper we describe a platform-oriented approach to providing assurance for plug & play medical systems as well as an associated assurance argument pattern

Tubulin response to intense nanosecond-scale electric field in molecular dynamics simulation

Intense pulsed electric fields are known to act at the cell membrane level and are already being exploited in biomedical and biotechnological applications. However, it is not clear if electric pulses within biomedically-attainable parameters could directly influence intra-cellular components such as cytoskeletal proteins. If so, a molecular mechanism of action could be uncovered for therapeutic applications of such electric fields. To help clarify this question, we first identified that a tubulin heterodimer is a natural biological target for intense electric fields due to its exceptional electric properties and crucial roles played in cell division. Using molecular dynamics simulations, we then demonstrated that an intense - yet experimentally attainable - electric field of nanosecond duration can affect the bβ-tubulin’s C-terminus conformations and also influence local electrostatic properties at the GTPase as well as the binding sites of major tubulin drugs site. Our results suggest that intense nanosecond electric pulses could be used for physical modulation of microtubule dynamics. Since a nanosecond pulsed electric field can penetrate the tissues and cellular membranes due to its broadband spectrum, our results are also potentially significant for the development of new therapeutic protocols

Effect of boundary conditions and geometry on the failure of cylindrical shell structures

In this paper, experimental and numerical studies are performed to determine the maximum deflection and strength of cylindrical shells. The considered models are subjected to concentrated loads applied progressively until plastic failure of the structures. In order to determine the effect of the geometrical parameters, several models with different thicknesses, lengths, and radius are considered and analysed with various boundary conditions. The numerical analysis is carried out by the finite element method using ABAQUS code. The main objective of the present investigation is to determine the maximum strength that caused damage of the models. The results of the experimental and numerical analysis are recorded, discussed and commented on. It is observed that the thickness, length,and radius dimensions with boundary conditions have great effect on the strength load values that create damage

Outcome measures of the surgery first approach for orthognathic correction of dentofacial deformities

Background: In the surgery-first approach (SFA) the orthognathic surgery is performed without the need for presurgical orthodontic treatment. Aim: This study was aimed at assessing the treatment durations and occlusal outcomes for a consecutive cohort of patients, with a range of dentofacial deformities, who have completed orthognathic treatment using the SFA. Methodology: The duration of orthognathic treatment was measured. The overall change in occlusion, and the quality of the final occlusion, were evaluated using the patients’ study casts. A single independent, calibrated, operator carried out the occlusal scores, using the validated Peer Assessment Rating (PAR) index. This was repeated to test intra-operator reliability. Results: A total of 51 patients completed surgery-first treatment during the study period. The mean age at surgery was 23.3 years. The pre-treatment skeletal jaw relationship was Class III in 39 cases, and Class II in 12 cases. The mean overall treatment duration was 11.7 months (SD = 5.7). The intra-examiner reliability of assessing the occlusion was high. The PAR scores confirmed a significant improvement in the quality of occlusion at the completion of treatment, which compares favourably with previous studies on the conventional orthodontics-first approach. Conclusion: The SFA can be effective at correcting both Class 2 and Class 3 malocclusion types with reduced treatment times