Biomechanical Properties Of Posterior To Anterior Lag Screw Insertion In Fibular Supination-External Rotation Fractures And Effect Of Engaged Cortical Thickness

The fracture pattern of supination-external rotation injury of the fibula is often reducible by lag screw fixation. This thesis is designed to evaluate biomechanical differences between lag screws inserted from an anterior to posterior direction and from a posterior to anterior direction and if the thickness of the anterior and posterior fibular cortices were similarly correlated. 5 donor-matched pairs of cadaver fibula were harvested and submitted to material testing following 3.5-mm cortical screw insertion from either an anterior to posterior direction or a posterior to anterior direction and screw insertion torque and axial pullout strength were measured. Computed tomography images of 40 patients undergoing preoperative planning for ankle injuries excluding the fibula were examined to define fibular cortical thickness. The anterior cortex of the distal fibula exhibited a radiographically greater thickness than that of the posterior cortex at the same level (p \u3c 0.001). The axial pullout strength of lag screws inserted from posterior to anterior was significantly greater than that of lag screws inserted from anterior to posterior (p \u3c 0.05). Screw insertion torque measurements demonstrated a similar trend although the data did not reach statistical significance (p = 0.056). For supination-external rotation fracture patterns of the distal fibula, posterior to anterior lag screw insertion exhibited superior biomechanical properties when compared to the anterior to posterior approach. These results also correlated with the cortical thickness of bone measured along the anterior fibula

Assessment of the risk of African swine fever introduction into Finland using NORA : a rapid tool for semiquantitative assessment of the risk

The NORA rapid risk assessment tool was developed for situations where there is a change in the disease status of easily transmissible animal diseases in neighbouring countries or in countries with significant interactions with Finland. The goal was to develop a tool that is quick to use and will provide consistent results to support risk management decisions. The model contains 63 questions that define the potential for entry and exposure by nine different pathways. The magnitude of the consequences is defined by 23 statements. The weight of different pathways is defined according to the properties of the assessed disease. The model was built as an Excel spreadsheet and is intended for use by animal health control administrators. As an outcome, the model gives the possible pathways of disease entry into the country, an overall approximation for the probability of entry and the subsequent exposure, an overall estimate for the consequences and a combined overall risk estimate (probability multiplied by magnitude of consequences). Model validity was assessed by expert panels. Outside Africa, African swine fever is currently established in Russia and Sardinia. In addition, there have been cases in both wild boar and domestic pigs in Latvia, Lithuania, Poland and Estonia. Finland has frequent contacts with Russia and Estonia, especially through passengers. The risk of African swine fever (ASF) introduction into Finland was tested with NORA for the situation in December 2015, when ASF was endemic in many parts of Russia, Africa and Sardinia and was present in Baltic countries and in Poland. African swine fever was assessed to have a high probability of entry into Finland, with high consequences and therefore a high overall risk

Computationally Efficient Forward Operator for Photoacoustic Tomography Based on Coordinate Transformations

IEEE Photoacoustic tomography (PAT) is an imaging modality that utilizes the photoacoustic effect. In PAT, a photoacoustic image is computed from measured data by modeling ultrasound propagation in the imaged domain and solving an inverse problem utilizing a discrete forward operator. However, in realistic measurement geometries with several ultrasound transducers and relatively large imaging volume, an explicit formation and use of the forward operator can be computationally prohibitively expensive. In this work, we propose a transformation based approach for efficient modeling of photoacoustic signals and reconstruction of photoacoustic images. In the approach, the forward operator is constructed for a reference ultrasound transducer and expanded into a general measurement geometry using transformations that map the formulated forward operator in local coordinates to the global coordinates of the measurement geometry. The inverse problem is solved using a Bayesian framework. The approach is evaluated with numerical simulations and experimental data. The results show that the proposed approach produces accurate three-dimensional photoacoustic images with a significantly reduced computational cost both in memory requirements and in time. In the studied cases, depending on the computational factors such as discretization, over 30-fold reduction in memory consumption and was achieved without a reduction in image quality compared to a conventional approach

Modelling of errors and uncertainties in photoacoustic tomography using a Bayesian framework

Photoacoustic tomography is studied in the framework of Bayesian inverse problems. Modelling of errors and uncertainties using Bayesian approximation error modelling is investigated. The approach is tested with simulation

Dynamics in Education Politics

In the field of comparative education without a strong theory-driven approach it is hard to go beyond merely listing the similarities and differences that make it possible to create countless rankings, but reveals little about specific and shared developmental processes between education systems. This book introduces a new theoretical framework characterised as Comparative Analytics of Dynamics in Education Politics (CADEP) as an ambitious response to this political, intellectual and scientific problem

Fundamental studies of gas phase ionic reactions by ion mobility spectrometry

Ion mobility spectrometry (IMS) provides a promising approach to the study of gas phase ionic reactions in buffer gases at unusually high pressures. This point is illustrated here by studies of the Sn2 nucleophilic displacement reaction, Cl(-) + CH3Br yields Br + CH3Br, using IMS at atmospheric pressure. The equilibrium clustering reaction, Cl(-)(CHCI3)(n - 1) + CHCI3 yields Cl(-)(CHCI3)(n), where n = 1 and 2, and the effect of clustering on the Sn2 reaction with CH3Br have also been characterized by this IMS-based kinetic method. Present problems and anticipated improvements in the application of ion mobility spectrometry to studies of other gas phase ionic processes are discussed

Synthetic Mimic of Antimicrobial Peptide with Nonmembrane-Disrupting Antibacterial Properties

Proteolysis in dairy lactic acid bacteria has been studied in great detail by genetic, biochemical and ultrastructural methods. From these studies the picture emerges that the proteolytic systems of lactococci and lactobacilli are remarkably similar in their components and mode of action. The proteolytic system consists of an extracellularly located serine-proteinase, transport systems specific for di-tripeptides and oligopeptides (> 3 residues), and a multitude of intracellular peptidases. This review describes the properties and regulation of individual components as well as studies that have led to identification of their cellular localization. Targeted mutational techniques developed in recent years have made it possible to investigate the role of individual and combinations of enzymes in vivo. Based on these results as well as in vitro studies of the enzymes and transporters, a model for the proteolytic pathway is proposed. The main features are: (i) proteinases have a broad specificity and are capable of releasing a large number of different oligopeptides, of which a large fraction falls in the range of 4 to 8 amino acid residues; (ii) oligopeptide transport is the main route for nitrogen entry into the cell; (iii) all peptidases are located intracellularly and concerted action of peptidases is required for complete degradation of accumulated peptides.

Effecting change by using innovative techniques in low risk projects

The ability to maximize the environmental value of reclamation is often constrained by engineering design criteria and protocol as well as specified standards. While standards minimize the chance of project failures, there are situations where strict adherence has stifled innovation. Evaluating the risks associated with projects can identify lower risk opportunities where innovative techniques can be explored. This paper presents a conceptual framework for evaluating risk and applies it to two scenarios; evaluating stream stabilization projects using rip rap and reclamation of acidic tailings. Cases studies are presented where low risk projects have used innovative techniques that have the potential to shift the paradigm with respect to commonly applied approaches in mine reclamation to improve the environmental values of reclamation.Non UBCUnreviewedOthe