Locally Adaptive Frames in the Roto-Translation Group and their Applications in Medical Imaging

Locally adaptive differential frames (gauge frames) are a well-known effective tool in image analysis, used in differential invariants and PDE-flows. However, at complex structures such as crossings or junctions, these frames are not well-defined. Therefore, we generalize the notion of gauge frames on images to gauge frames on data representations $U:\mathbb{R}^{d} \rtimes S^{d-1} \to \mathbb{R}$ defined on the extended space of positions and orientations, which we relate to data on the roto-translation group $SE(d)$, $d=2,3$. This allows to define multiple frames per position, one per orientation. We compute these frames via exponential curve fits in the extended data representations in $SE(d)$. These curve fits minimize first or second order variational problems which are solved by spectral decomposition of, respectively, a structure tensor or Hessian of data on $SE(d)$. We include these gauge frames in differential invariants and crossing preserving PDE-flows acting on extended data representation $U$ and we show their advantage compared to the standard left-invariant frame on $SE(d)$. Applications include crossing-preserving filtering and improved segmentations of the vascular tree in retinal images, and new 3D extensions of coherence-enhancing diffusion via invertible orientation scores

Prognostic factors for outcomes of idiopathic sudden sensorineural hearing loss: protocol for the SeaSHeL national prospective cohort study

INTRODUCTION: The mainstay of treatment for idiopathic sudden sensorineural hearing loss (SSNHL) includes oral steroids, intratympanic steroid injections or a combination of both. The National Institute for Health and Care Excellence, in their recent hearing loss guidelines, highlighted the paucity of evidence assessing the comparative effectiveness of these treatments; and the National Institute for Health Research (NIHR) Health Technology Assessment Programme has since released a commissioned call for a trial to identify the most effective route of administration of steroids as a first-line treatment for idiopathic SSNHL. For such trials to be run effectively, reliable information is needed on patients with SSNHL: where they present, numbers, demographics, treatment pathways, as well as outcomes. This study will collect these data in a nationwide cohort study of patients presenting with SSNHL across 97 National Health Service (NHS) trusts. The study will be delivered through ear, nose and throat (ENT) trainee networks, the NIHR Clinical Research Network (CRN) Audiology Champions and the NIHR CRN. Importantly, this study will also provide a dataset to develop a prognostic model to predict recovery for patients with idiopathic SSNHL. The study objectives are to: (1) map the patient pathway and identify the characteristics of adult patients presenting to NHS ENT and hearing services with SSNHL, (2) develop a prognostic model to predict recovery for patients with idiopathic SSNHL and (3) establish the impact of idiopathic SSNHL on patients' quality of life (QoL). METHODS AND ANALYSIS: Study design: national multicentre prospective cohort study across 97 NHS trusts. INCLUSION CRITERIA: adult patients presenting to NHS ENT and hearing services with SSNHL. OUTCOMES: change in auditory function; change in QoL score. ANALYSIS: multivariable prognostic model, using prespecified candidate predictors. Mean change in QoL scores will be calculated from initial presentation to follow-up. ETHICS AND DISSEMINATION: Health Research Authority and NHS Research Ethics Committee approved the study. Publication will be on behalf of study sites and collaborators. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT04108598)

Development of a prediction model for recurrence in patients with colorectal peritoneal metastases undergoing cytoreductive surgery with hyperthermic intraperitoneal chemotherapy

INTRODUCTION: Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) improves survival outcomes for selected patients with colorectal peritoneal metastases (PM), but recurrence rates are high. The aim of this study was to develop a tool to predict recurrence in patients with colorectal PM that undergo CRS-HIPEC.MATERIALS AND METHODS: For this retrospective cohort study, data of patients that underwent CRS-HIPEC for colorectal PM from four Dutch HIPEC centers were used. Exclusion criteria were perioperative systemic therapy and peritoneal cancer index (PCI) ≥20. Nine previously identified factors were considered as predictors: gender, age, primary tumor characteristics (location, nodal stage, differentiation, and mutation status), synchronous liver metastases, preoperative Carcino-Embryonal Antigen (CEA), and peritoneal cancer index (PCI). The prediction model was developed using multivariable Cox regression and validated internally using bootstrapping. The performance of the model was evaluated by discrimination and calibration.RESULTS: In total, 408 patients were included. During the follow-up, recurrence of disease occurred in 318 patients (78%). Significant predictors of recurrence were PCI (HR 1.075, 95% CI 1.044-1.108) and primary tumor location (left sided HR 0.719, 95% CI 0.550-0.939). The prediction model for recurrence showed fair discrimination with a C-index of 0.64 (95% CI 0.62, 0.66) after internal validation. The model was well-calibrated with good agreement between the predicted and observed probabilities.CONCLUSION: We developed a prediction tool that could aid in the prediction of recurrence in patients with colorectal PM who undergo CRS-HIPEC.</p

Development of a prediction model for recurrence in patients with colorectal peritoneal metastases undergoing cytoreductive surgery with hyperthermic intraperitoneal chemotherapy

INTRODUCTION: Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) improves survival outcomes for selected patients with colorectal peritoneal metastases (PM), but recurrence rates are high. The aim of this study was to develop a tool to predict recurrence in patients with colorectal PM that undergo CRS-HIPEC.MATERIALS AND METHODS: For this retrospective cohort study, data of patients that underwent CRS-HIPEC for colorectal PM from four Dutch HIPEC centers were used. Exclusion criteria were perioperative systemic therapy and peritoneal cancer index (PCI) ≥20. Nine previously identified factors were considered as predictors: gender, age, primary tumor characteristics (location, nodal stage, differentiation, and mutation status), synchronous liver metastases, preoperative Carcino-Embryonal Antigen (CEA), and peritoneal cancer index (PCI). The prediction model was developed using multivariable Cox regression and validated internally using bootstrapping. The performance of the model was evaluated by discrimination and calibration.RESULTS: In total, 408 patients were included. During the follow-up, recurrence of disease occurred in 318 patients (78%). Significant predictors of recurrence were PCI (HR 1.075, 95% CI 1.044-1.108) and primary tumor location (left sided HR 0.719, 95% CI 0.550-0.939). The prediction model for recurrence showed fair discrimination with a C-index of 0.64 (95% CI 0.62, 0.66) after internal validation. The model was well-calibrated with good agreement between the predicted and observed probabilities.CONCLUSION: We developed a prediction tool that could aid in the prediction of recurrence in patients with colorectal PM who undergo CRS-HIPEC.</p

NeuroSpeech

NeuroSpeech is a software for modeling pathological speech signals considering different speech dimensions: phonation, articulation, prosody, and intelligibility. Although it was developed to model dysarthric speech signals from Parkinson's patients, its structure allows other computer scientists or developers to include other pathologies and/or measures. Different tasks can be performed: (1) modeling of the signals considering the aforementioned speech dimensions, (2) automatic discrimination of Parkinson's vs. non-Parkinson's, and (3) prediction of the neurological state according to the Unified Parkinson's Disease Rating Scale (UPDRS) score. The prediction of the dysarthria level according to the Frenchay Dysarthria Assessment scale is also provided

Transformation Textures in Zirconia

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65433/1/j.1151-2916.1993.tb03696.x.pd

Sintering and compensation effect of donor and acceptor codoped 3 mol% Y 2 O 3 -ZrO 2

Addition of 0.15–0.5 mol% acceptor oxide, Al 2 O 3 , to 3 mol% Y 2 O 3 -ZrO 2 results in enhanced densification at 1350°C. The enhancement is accounted for by a liquid phase sintering mechanism. While the addition of donor oxide, Ta 2 O 5 , of 0.15–2.5 mol% at 1300–1600°C results in the decrease of final density and in the destabilization of the tetragonal (t) phase of the 3 mol% Y 2 O 3 -t-ZrO 2 (TZP). X-ray diffractometry (XRD) reveals that the Ta 2 O 5 -added 3 mol% Y 2 O 3 -ZrO 2 contains monoclinic (m) ZrO 2 phase and a second Ta 2 Zr 6 O 17 phase. The decrease is attributed to the increase of m-ZrO 2 content in these samples. Complete phase transformation from t-ZrO 2 to m-ZrO 2 observed in samples added with 2.5 mol% Ta 2 O 5 is interpreted by the compensation effect based on donor and acceptor codoping defect chemistry.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44737/1/10853_2004_Article_BF00356138.pd

Sintering and compensation effect of donor- and acceptor-codoped 3mol% Y 2 O 3 -ZrO 2

Addition of ∼0.15–0.5 mol% acceptor oxide, Al 2 O 3 , to 3 mol% Y 2 O 3 -ZrO 2 results in enhanced densification at 1350 °C. The enhancement is accounted for by a liquid phase sintering mechanism. The addition of donor oxide, Ta 2 O 5 , of 0.15–2.5 mol % at 1300–1600 °C results in the destabilization of tetragonal (t-) phase and the decrease of final density in 3 mol% Y 2 O 3 -TZP (tetragonal ZrO 2 polycrystals). X-ray diffractometry (XRD) reveals that the Ta 2 O 5 -added 3 mol% Y 2 O 3 -ZrO 2 contains monoclinic (m-) ZrO 2 and a second phase of Ta 2 Zr 6 O 17 . The decreasing in final density is attributed to the increase of m-ZrO 2 content. Complete destabilization of t-ZrO 2 to m-ZrO 2 in samples added with 2.5 mol% Ta 2 O 5 is interpreted by the compensation effect based on donor- and acceptor-codoping defect chemistry.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44714/1/10853_2005_Article_BF01166021.pd