A5030373716- Cerebrovascular and Carotid Artery Diseases
- Acute Ischemic Stroke Management
- Intracranial Aneurysms: Treatment and Complications
- Mechanical and Optical Resonators
- Cerebrospinal fluid and hydrocephalus
- Micro and Nano Robotics
- Radiomics and Machine Learning in Medical Imaging
- Structural Load-Bearing Analysis
- Near-Field Optical Microscopy
- Force Microscopy Techniques and Applications
- Matrix Theory and Algorithms
- Medical Image Segmentation Techniques
- Structural Analysis and Optimization
- Neural Networks and Applications
- Composite Structure Analysis and Optimization
- Cardiac, Anesthesia and Surgical Outcomes
- Elasticity and Material Modeling
- Machine Learning and ELM
- Advanced X-ray and CT Imaging
- Vibration and Dynamic Analysis
- Retinal Imaging and Analysis
- Advanced Surface Polishing Techniques
- Nonlocal and gradient elasticity in micro/nano structures
- Experimental Learning in Engineering
- Structural Behavior of Reinforced Concrete
Canon (United States)
2023
University at Buffalo, State University of New York
2021-2022
University of Tehran
2018
Stent retriever thrombectomy is a pre-eminent treatment modality for large vessel ischaemic stroke. Simulation of could help understand stent and clot mechanics in failed cases provide digital testbed the development new, safer devices. Here, we present novel, silico method using hybrid finite-element analysis (FEA) smoothed particle hydrodynamics (SPH). Inspired by its biological structure components, blood was modelled with FEA–SPH method. The Solitaire self-expanding parametrically...
Background Biological interpretability of ischemic stroke clot imaging remains challenging. Objective To carry out paired CT/micro-CT clots retrieved by thrombectomy with the aim identifying interpretable image features that are correlated among pretreatment modalities and post-treatment histopathology. Methods We performed multimodal CT histology for 10 mechanical thrombectomy. Clots were manually segmented from co-registered, angiography (CTA) non-contrast (NCCT). For same cases,...
Infarct volume measured from 2,3,5-triphenyltetrazolium chloride (TTC)-stained brain slices is critical to in vivo stroke models. In this study, we developed an interactive, tunable, software that automatically computes whole-brain infarct metrics serial TTC-stained sections.Three rat ischemic cohorts were used study (Total n = 91 rats; Cohort 1 21, 2 40, 3 30). For each, brains serially-sliced, stained with TTC and scanned on both anterior posterior sides. Ground truth annotation...
A direct aspiration-first pass technique (ADAPT) has recently gained popularity for the treatment of large vessel ischemic stroke. Here, we sought to create a machine learning-based model that uses pre-treatment imaging metrics predict successful outcomes ADAPT in middle cerebral artery (MCA) stroke cases. In 119 MCA strokes treated by ADAPT, calculated four parameters—clot length, perviousness, distance from internal carotid (ICA) and angle interaction (AOI) between clot/catheter. We...
Enodvascular coils treat intracranial aneurysms (IAs) by causing them to occlude thrombosis. Ideally, coiled IAs eventually in the long-term. However, 20.8% are found incompletely occluded at treatment follow-up. Computer simulations of coiling and its effect on aneurysmal flow could help clinicians predict outcomes a priori, but it requires accurate modeling their deployment procedure. In addition being accurate, must be efficient used as bedside tool. To date, several virtual techniques...
Time-of-flight (TOF) magnetic resonance angiography is a non-invasive imaging modality for the diagnosis of intracranial atherosclerotic diseases (ICAD). Evaluation degree stenosis and status posterior anterior communicating arteries to supply enough blood flow distal very critical, which requires accurate evaluation arteries. Recently, deep-learning methods have been firmly established as robust tool in medical image segmentation, has resulted developing multiple customized algorithms. For...
Background Vascular geometry plays an important role in stroke thrombectomy outcomes, but few studies have examined complex characteristics of vessel morphology. The authors hypothesized that engineered cross‐section features could be used to predict first‐pass effect (FPE). Methods analyzed computed tomography angiography and noncontrast tomagraphy from 50 patients with anterior circulation thrombectomy. After segmentation, traditional metrics (vessel tortuosity angulation) were calculated...
Free vibration and wave analysis of thick rectangular graphene are studied by employing the propagation method. To consider small-scale effects thickness a plate in nanoscales, equations motions represented Eringen nonlocal theory coupled with Mindlin plates. solve governing motion technique, reflection matrices derived. These combined to obtain exact natural frequencies sheets for all six possible boundary conditions. check accuracy reliability method, compared results literature, excellent...
Background: Paired analysis of ischemic stroke clot histology and pre-treatment CT imaging could identify digital indicators treatment outcome or etiology. Yet, differences in scale limit our ability to interpret the biology from images. Hypothesis: Radiomic resected clots on microCT has potential important, biologically-interpretable features that are correlated among modalities (CTA, nCCT) post-treatment histopathology. Methods: We performed multimodal 10 retrieved by mechanical...
In many cases, beam to column connections in structural frames are semi rigid, but they considered be ideally rigid or pinned due their computational complexity and shortage of designing methods. this paper, as linear rotational springs with variable stiffness. Moreover, the main contribution present study is a preliminary design method moment resisting frames, considering behavior connections, by means presented diagrams for different frames. These relate three features frame together;...
Finding the inverse of a matrix is an open problem especially when it comes to engineering problems due their complexity and running time (cost) inversion algorithms.An optimum strategy invert is, first, reduce simple form, only then beginning mathematical procedure.For symmetric matrices, preferred form tridiagonal.This makes tridiagonal matrices be high interest in applied mathematics problems.This study presents efficient, exact analytical approach for finding inverse, decomposition,...
The dynamic behavior of AFM is studied taking into account the nonlinear interaction forces between probe and sample. exerted on free end micro-beam are simulated with third degree polynomial. effect some parameters dynamics studied. results show that frequency response not sensitive to tip mass in case both sample cantilever vibration. vibration in-phase anti-phase although amplitude very small compared cantilever, it has great resonant cantilever.
Atomic Force Microscopy with SideWall (AFM SW) is widely used for nano-scale surface measurements at side surfaces. In the current study, by taking into consideration effects of sidewall beam and its probe, an analytical method developed to explore dynamics AFM-SW. The effect probe mass, extension length, tip sample interactions on resonance frequencies amplitude Micro-Cantilever investigated. obtained results model demonstrate significant these parameters To verify accuracy model, are...
Gradient descent optimizations and backpropagation are the most common methods for training neural networks, but they computationally expensive real time applications, need high memory resources, difficult to converge many networks large datasets. [Pseudo]inverse models network have emerged as powerful tools overcome these issues. In order effectively implement methods, structured pruning maybe be applied produce sparse networks. Although efficient in usage, of their algorithms use same...
Introduction: Ischemic stroke is a major cause of mortality and morbidity worldwide. Stent retriever thrombectomy (SRT) preeminent treatment for large vessel stroke. While effective, SRT only attains first pass success in 30% cases, can complications, like embolus formation. In silico modeling facilitates understanding the such complications. Hypothesis: A combination finite element analysis (FEA) smoothed-particle hydrodynamics (SPH) accurately simulate SRT. Methods: We developed workflow...