Multiatlas segmentation as nonparametric regression

pre-printThis paper proposes a novel theoretical framework to model and analyze the statistical characteristics of a wide range of segmentation methods that incorporate a database of label maps or atlases; such methods are termed as label fusion or multiatlas segmentation.We model these multiatlas segmentation problems as nonparametric regression problems in the high-dimensional space of image patches. We analyze the nonparametric estimator's convergence behavior that characterizes expected segmentation error as a function of the size of the multiatlas database. We show that this error has an analytic form involving several parameters that are fundamental to the specific segmentation problem (determined by the chosen anatomical structure, imaging modality, registration algorithm, and label-fusion algorithm). We describe how to estimate these parameters and show that several human anatomical structures exhibit the trends modeled analytically. We use these parameter estimates to optimize the regression estimator.We show that the expected error for large database sizes is well predicted by models learned on small databases. Thus, a few expert segmentations can help predict the database sizes required to keep the expected error below a specified tolerance level. Such cost-benefit analysis is crucial for deploying clinical multiatlas segmentation systems

An Unusual Presentation of Immunoglobulin G4-Related Disease (IgG4-RD) Causing Subglottic Stenosis

Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated fibroinflammatory condition that is known to involve multiple organs and was first described as an entity in 2003. It is characterized by lesions with a dense lymphoplasmacytic infiltrate, IgG4-positive plasma cells, storiform fibrosis, and frequently elevated serum IgG4 levels. Organs that are commonly involved include the pancreas, biliary tree, salivary glands, periorbital tissues, kidneys, retroperitoneum, lungs, pleura, thyroid, aorta, and lymph nodes. Rarer manifestations of IgG4-RD include central nervous system (CNS) involvement, prostatitis, mastitis, midline destructive disease, and nasopharyngeal disease. In this report, we discuss an atypical case of a young woman with laryngeal subglottic involvement leading to stenosis and airway obstruction, which was ultimately successfully managed with systemic immunosuppression

3D Laser-and-tissue Agnostic Data-driven Method for Robotic Laser Surgical Planning

In robotic laser surgery, shape prediction of an one-shot ablation cavity is an important problem for minimizing errant overcutting of healthy tissue during the course of pathological tissue resection and precise tumor removal. Since it is difficult to physically model the laser-tissue interaction due to the variety of optical tissue properties, complicated process of heat transfer, and uncertainty about the chemical reaction, we propose a 3D cavity prediction model based on an entirely data-driven method without any assumptions of laser settings and tissue properties. Based on the cavity prediction model, we formulate a novel robotic laser planning problem to determine the optimal laser incident configuration, which aims to create a cavity that aligns with the surface target (e.g. tumor, pathological tissue). To solve the one-shot ablation cavity prediction problem, we model the 3D geometric relation between the tissue surface and the laser energy profile as a non-linear regression problem that can be represented by a single-layer perceptron (SLP) network. The SLP network is encoded in a novel kinematic model to predict the shape of the post-ablation cavity with an arbitrary laser input. To estimate the SLP network parameters, we formulate a dataset of one-shot laser-phantom cavities reconstructed by the optical coherence tomography (OCT) B-scan images for the data-driven modelling. To verify the method. The learned cavity prediction model is applied to solve a simplified robotic laser planning problem modelled as a surface alignment error minimization problem. The initial results report (91.1 +- 3.0)% 3D-cavity-Intersection-over-Union (3D-cavity-IoU) for the 3D cavity prediction and an average of 97.9% success rate for the simulated surface alignment experiments

Ultrasonic imaging of electrofusion welded polyethylene pipes employed in utilities industry

Electrofusion welding (EFW) is a widely used technique for joining polyethylene pipes in the oil, gas and water industry. Like many welding and joining methods, the joints created by EFW can exhibit a range of flaw types that can be attributed to process variables such as: poor preparation of the parent material, contamination of the weld surfaces prior to welding and operator and/or equipment failure during the welding process. This paper describes ultrasonic testing using 128-channel linear array with a DYNARAY system to acquire data from a range of joints created using EFW. The samples were created in the laboratory with a range of defects that represent those commonly observed in the field. The samples were subsequently destructively tested using tensile testing of the coupling-pipe interface. Good corroboration was achieved between the observed weld quality from the ultrasonic data and the weld strength determined by the destructive testing

Species-Specific Effects of Cation Channel TRPM4 Small-Molecule Inhibitors

Background: The Transient Receptor Potential Melastatin member 4 (TRPM4) gene encodes a calcium-activated non-selective cation channel expressed in several tissues. Mutations in TRPM4 have been reported in patients with different types of cardiac conduction defects. It is also linked to immune response and cancers, but the associated molecular mechanisms are still unclear. Thus far, 9-phenanthrol is the most common pharmacological compound used to investigate TRPM4 function. We recently identified two promising aryloxyacyl-anthranilic acid compounds (abbreviated CBA and NBA) inhibiting TRPM4. However, all aforementioned compounds were screened using assays expressing human TRPM4, whereas the efficacy of mouse TRPM4 has not been assessed. Mouse models are essential to investigate ion channel physiology and chemical compound efficacy. Aim: In this study, we performed comparative electrophysiology experiments to assess the effect of these TRPM4 inhibitors on human and mouse TRPM4 channels heterologously expressed in TsA-201 cells. Methods and Results: We identified striking species-dependent differences in TRPM4 responses. NBA inhibited both human and mouse TRPM4 currents when applied intracellularly and extracellularly using excised membrane patches. CBA inhibited human TRPM4, both intracellularly and extracellularly. Unexpectedly, the application of CBA had no inhibiting effect on mouse TRPM4 current when perfused on the extracellular side. Instead, its increased mouse TRPM4 current at negative holding potentials. In addition, CBA on the intracellular side altered the outward rectification component of the mouse TRPM4 current. Application of 9-phenanthrol, both intracellularly and extracellularly, inhibited human TRPM4. For mouse TRPM4, 9-phenanthrol perfusion led to opposite effects depending on the site of application. With intracellular 9-phenanthrol, we observed a tendency towards potentiation of mouse TRPM4 outward current at positive holding potentials. Conclusion: Altogether, these results suggest that pharmacological compounds screened using “humanised assays” should be extensively characterised before application in vivo mouse models

St. Louis Regional Greenhouse Gas Reduction Strategy

This semester the Greenhouse Gas Reduction Team (GHGRT) of the Sustainability Exchange program at Washington University in St. Louis was tasked with initial planning to decrease greenhouse gas emissions in the St. Louis area for OneSTL. To do so, GHGRT began by meeting with experts in the field, including Rene Dulle, Tim Michels, and Emily Andrews, to determine the best course of action and get insight into the situation as it stands. Based on this information, we decided to focus on building energy use and resulting carbon emissions. The team then researched energy use in the city of St. Louis and investigated Ameren’s plan for converting from fossil fuels to carbon neutral energy by 2050. The team also investigated paths for funding for St. Louis citizens through avenues such as the Inflation Reduction Act (IRA), and rebates from Spire and Ameren. The team also considered non-technical and non-monetary strategies for reducing carbon emissions, focusing on community education. To complete our analysis, we created several model scenarios for citizens and buildings in St. Louis to show how our strategies could be implemented in the real world. In this report we also discussed some challenges we had while completing the project as well as some expected future steps for this project

Species-specific effects of cation channel TRPM4 small-molecule inhibitors

Background The Transient Receptor Potential Melastatin member 4 (TRPM4) gene encodes a calcium-activated non-selective cation channel expressed in several tissues. Mutations in TRPM4 have been reported in patients with different types of cardiac conduction defects. It is also linked to immune response and cancers, but the associated molecular mechanisms are still unclear. Thus far, 9-phenanthrol is the most common pharmacological compound used to investigate TRPM4 function. We recently identified two promising aryloxyacyl-anthranilic acid compounds (abbreviated CBA and NBA) inhibiting TRPM4. However, all afore-mentioned compounds were screened using assays expressing human TRPM4, whereas the efficacy on mouse TRPM4 has not been assessed. Mouse models are essential to investigate ion channel physiology and chemical compound efficacy. Aim In this study, we performed comparative electro-physiology experiments to assess the effect of these TRPM4 inhibitors on human and mouse TRPM4 channels heterologously expressed in TsA-201 cells. Methods and Results We identified striking species-dependent differences in TRPM4 responses. NBA inhibited both human and mouse TRPM4 currents when applied intracellularly and extracellularly using excised membrane patches. CBA inhibited human TRPM4, both intracellularly and extracellularly. Unexpectedly, the application of CBA had no inhibiting effect on mouse TRPM4 current when perfused on the extracellular side. Instead, it increased mouse TRPM4 current at negative holding potentials. In addition, CBA on the intracellular side altered the outward rectification component of the mouse TRPM4 current. Application of 9-phenanthrol, both intracellularly and extracellularly, inhibited human TRPM4. For mouse TRPM4, 9-phenanthrol perfusion led to opposite effects depending on the site of application. With intracellular 9-phenanthrol, we observed a tendency towards potentiation of mouse TRPM4 outward current at positive holding potentials. Conclusion Altogether, these results suggest that pharmacological compounds screened using “humanised assays” should be extensively characterised before application in in vivo mouse models

D&T making a difference in black ethnic minority education: the Sheffield LEA ICSYS partnership

An innovative interpretation of the Inequality Challenge for South Yorkshire Schools (ICSYS) project by Sheffield LEA has resulted in a partnership between the LEA, local schools and Sheffield Hallam University (SHU). The aim of the project is to provide black ethnic minority (BEM) pupils with a high quality Design and Technology (D&T) experience, which promotes career opportunities in the field of contemporary manufacturing and engineering. To achieve this aim computer aided design and manufacturing (CAD/CAM), acknowledged as a highly motivating aspect of the modern D&T curriculum, has been selected as the vehicle for the teaching and learning experiences that the pupils will be exposed to. The project is funded by Objective 1 European Social Funding via the Learning and Skills Council. To achieve the aim the project incorporated the following elements: • DATA accredited CAD/CAM INSET in Speedstep and Artcam for teachers in participating schools. • A programme of pupil visits to manufacturing industry where the focus was on applications of CAD/CAM processes in ‘high tech’ industry. • CAD/CAM workshops for pupils in the university where they participated in small group activities led by D&T initial teacher education (ITE) students. • The development of innovative CAD/CAM projects with the aim of encouraging BEM pupils to consider careers in ‘high tech’ manufacturing. • Opportunities for BEM pupils to gain experience of ‘university life’. • Follow up CAD/CAM teaching in schools by university staff. • Opportunities for pupils to develop their presentation skills. Initial research drawn from industrial sources highlighted the need for increasing the supply of engineers, particularly in South Yorkshire, and called for further educational initiatives. Research of national data confirmed the LEA’s view that engineering and manufacturing were not strong career aspirations for BEM pupils. Further research with BEM pupils confirmed this. During the ICSYS experience pupils’ views of manufacturing, particularly the ‘high tech.’ aspect represented by CAD/CAM were monitored by questionnaires. Triangulation of the research was by an independent evaluation using semi-structured interview techniques. The paper concludes with details of the extent to which pupils attitudes can be changed by this type of positive intervention. Additionally, it details those areas of the project which have been particularly successful so providing helpful information to both present and future D&T teachers whose groups include BEM pupils

Beta-Blocker Use and 30-Day All-Cause Readmission in Medicare Beneficiaries With Systolic Heart Failure

BACKGROUND: Beta-blockers improve outcomes in patients with systolic heart failure. However, it is unknown whether their initial negative inotropic effect may increase 30-day all-cause readmission, a target outcome for Medicare cost reduction and financial penalty for hospitals under the Affordable Care Act. METHODS: Of the 3067 Medicare beneficiaries discharged alive from 106 Alabama hospitals (1998-2001) with a primary discharge diagnosis of heart failure and ejection fraction RESULTS: Beta-blocker use was not associated with 30-day all-cause readmission (hazard ratio [HR] 0.87; 95% confidence interval [CI], 0.64-1.18) or heart failure readmission (HR 0.95; 95% CI, 0.57-1.58), but was significantly associated with lower 30-day all-cause mortality (HR 0.29; 95% CI, 0.12-0.73). During 4-year postdischarge, those in the beta-blocker group had lower mortality (HR 0.81; 95% CI, 0.67-0.98) and combined outcome of all-cause mortality or all-cause readmission (HR 0.87; 95% CI, 0.74-0.97), but not with all-cause readmission (HR 0.89; 95% CI, 0.76-1.04). CONCLUSIONS: Among hospitalized older patients with systolic heart failure, discharge prescription of beta-blockers was associated with lower 30-day all-cause mortality and 4-year combined death or readmission outcomes without higher 30-day readmission