New Radiomic Markers of Pulmonary Vein Morphology Associated With Post-Ablation Recurrence of Atrial Fibrillation.

To identify radiomic and clinical features associated with post-ablation recurrence of AF, given that cardiac morphologic changes are associated with persistent atrial fibrillation (AF), and initiating triggers of AF often arise from the pulmonary veins which are targeted in ablation. Subjects with pre-ablation contrast CT scans prior to first-time catheter ablation for AF between 2014-2016 were retrospectively identified. A training dataset (D) was constructed from left atrial and pulmonary vein morphometric features extracted from equal numbers of consecutively included subjects with and without AF recurrence determined at 1 year.

A new machine learning approach for predicting likelihood of recurrence following ablation for atrial fibrillation from CT.

Objective: To investigate left atrial shape differences on CT scans of atrial fibrillation (AF) patients with (AF+) versus without (AF-) post-ablation recurrence and whether these shape differences predict AF recurrence.

Methods: This retrospective study included 68 AF patients who had pre-catheter ablation cardiac CT scans with contrast. AF recurrence was defined at 1 year, excluding a 3-month post-ablation blanking period.

Machine Learning-Derived Fractal Features of Shape and Texture of the Left Atrium and Pulmonary Veins From Cardiac Computed Tomography Scans Are Associated With Risk of Recurrence of Atrial Fibrillation Postablation.

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Machine Learning Prediction of Response to Cardiac Resynchronization Therapy: Improvement Versus Current Guidelines.

Background: Cardiac resynchronization therapy (CRT) has significant nonresponse rates. We assessed whether machine learning (ML) could predict CRT response beyond current guidelines.

Methods: We analyzed CRT patients from Cleveland Clinic and Johns Hopkins.

Biomechanics of byssal threads outside the Mytilidae: Atrina rigida and Ctenoides mitis.

The byssus is the set of proteinaceous threads widely used by bivalves to attach themselves to the substrate. Previous researchers have focused on a single byssate family, the Mytilidae. However, the properties of byssal threads from species outside this family are of interest - first, because evolutionary patterns are only detectable if species from a range of taxa are examined, and second, because recent biomimetic research efforts would benefit from a wider range of ;mussel glue' exemplars.

A comparative study of the mechanical properties of Mytilid byssal threads.

Mytilid bivalves employ a set of threads (the byssus) to attach themselves to both hard and soft substrates. In this study, we measured the mechanical properties of byssal threads from two semi-infaunal mytilids (Geukensia demissa Dillwyn and Modiolus modiolus Linnaeus) and two epifaunal mytilids (Mytilus californianus Conrad and Mytilus edulis Linnaeus). We compared material properties with and without the assumption that changes of length and area during tensile testing are insignificant, demonstrating that previous researchers have overestimated extensibility values by 30% and may also have underestimated strength values.

Functional consequences of tooth design: effects of blade shape on energetics of cutting.

Dental structures capture, retain and fragment food for ingestion. Gnathostome dentition should be viewed in the context of the prey's material properties. Animal muscle and skin are mechanically tough materials that resist fragmentation unless energy is continually supplied directly to the tip of the fracture by some device such as a blade edge.

A novel crustacean swimming stroke: coordinated four-paddled locomotion in the cypridoidean ostracode Cypridopsis vidua (Müller).

Despite the diversity and ecological importance of cypridoidean ostracodes, there have been no kinematic studies of how they swim. We used regular and high-speed video of tethered ostracodes to document locomotion in the cypridoidean species Cypridopsis vidua. Swimming in this species is drag-based, with thrust provided by both antennulae and antennae.

Effects of size and behavior on aerial performance of two species of flying snakes (Chrysopelea).

Aerial locomotion in snakes (genus Chrysopelea) is kinematically distinct from any other type of gliding or powered flight, with prominent, high amplitude body undulations visually dominating the behavior. Because it is not known how flying snakes produce aerodynamic forces in flight, the factors that determine snake flight performance are not clear. In this study, the effects of size and behavior on aerial performance were examined both within a species (C.

A 3-D kinematic analysis of gliding in a flying snake, Chrysopelea paradisi.

Flying snake species (Chrysopelea) locomote through the air despite a lack of appendages or any obvious external morphological specialization for flight. Here photogrammetric techniques were used to investigate C. paradisi's aerial trajectory in three dimensions.

A Triassic aquatic protorosaur with an extremely long neck.

By Middle Triassic time, a number of reptile lineages had diversified in shallow epicontinental seas and intraplatform basins along the margins of parts of Pangea, including the giraffe-necked protorosaurid reptile Tanystropheus from the Western Tethys (Europe and the Middle East), which grew to approximately 5 to 6 m long. Here we report another long-necked fossil, Dinocephalosaurus, from southwestern China, recently collected in Middle Triassic marine deposits approximately 230 million years old. This taxon represents unambiguous evidence for a fully aquatic protorosaur.

FATIGUE DAMAGE: REPEATED LOADING ENABLES CRABS TO OPEN LARGER BIVALVES.

Observations of behavior and direct measurements of force indicated that the cancrid crab Cancer productus could directly crush only the smallest specimens of Protothaca staminea, a venerid bivalve. Crabs opened larger P. staminea by repeatedly loading the same region of the bivalve's shell with a chela; we hypothesized that this repeated loading caused fatigue of the shell material.