Recent uci_eng_eecs items

Integrated Strain–Flow Analysis for Early Assessment of Right Ventricular Dysfunction in Pulmonary Arterial Hypertension

Thu, 21 May 2026 00:00:00 +0000

PurposeEarly detection of right ventricular (RV) dysfunction is essential in pulmonary arterial hypertension (PAH) but remains challenging using conventional echocardiography. This study investigates the feasibility of a noninvasive, physics-based framework using three-dimensional (3D) echocardiography that integrates myocardial strain and volumetric flow analysis to characterize RV mechanical performance across stages of PAH.MethodsA prospective pilot study (N = 15) enrolled healthy controls, PAH patients with preserved RV size, and PAH patients with RV dysfunction. Deformation was evaluated by principal strain analysis and by conventional (longitudinal, circumferential) components. Hemodynamic metrics included hemodynamic forces and energetic properties that were derived using a physics-informed volumetric echocardiographic particle image velocimetry (V-Echo-PIV) method applied to contrast-enhanced acquisitions.ResultsDeformation analysis revealed that longitudinal...

Towards Verifying Crash Consistency

Thu, 23 Apr 2026 00:00:00 +0000

Compute Express Link (CXL) memory sharing, persistent memory, and other related technologies allow data to survive crash events. A key challenge is ensuring that data is consistent after crashes such that it can be safely accessed. While there has been much work on bug-finding tools for persistent memory programs, these tools cannot guarantee that a program is crash-consistent. In this paper, we present a language, CrashLang, and its type system, that together guarantee that well-typed data structure implementations written in CrashLang are crash-consistent. CrashLang leverages the well-known commit-store pattern in which a single store logically commits an entire data structure operation. In this paper, we prove that well-typed CrashLang programs are crash-consistent, and provide a prototype implementation of the CrashLang compiler. We have evaluated CrashLang on five benchmarks: the Harris linked list, the Treiber stack, the Michael–Scott queue, a Read-Copy-Update binary search...

Automated Insertion of Flushes and Fences for Persistency

Thu, 23 Apr 2026 00:00:00 +0000

CXL shared memory and persistent memory allow the contents of memory to persist beyond crashes. Stores to persistent or CXL memory are typically not immediately made persistent; developers must manually flush the corresponding cache lines to force the data to be written to the underlying storage. Correctly using flush and fence operations is known to be challenging. While state-of-the-art tools can find missing flush instructions, they often require bug-revealing test cases. No existing tools can ensure the absence of missing flush bugs. In this paper, we present PMRobust, a compiler that automatically inserts flush and fence operations to ensure that code using persistent memory is free from missing flush and fence bugs. PMRobust employs a novel static analysis with optimizations that target newly allocated objects. We have evaluated PMRobust on persistent memory libraries and several persistent memory data structures and measured a geometric mean overhead of 0.26% relative to...

HyperXite 9

Wed, 15 Apr 2026 00:00:00 +0000

The overall objective for HyperXite 9 was to design and build a more robust, and reliable pod, capable of proving the feasibility of a high-speed transportation system. We are working to improve a linear induction motor as the pod's propulsion system. We are also designing and implementing a thermal cooling system to actively dissipate the heat generated by this propulsion system. Our team is comprised of the following 7 subteams: Static Structures, Braking & Pneumatics, Dynamic Structures, Propulsion, Power Systems, Control Systems, and Outreach.

NUDGING: Inference-time Alignment of LLMs via Guided Decoding

Wed, 11 Feb 2026 00:00:00 +0000

Large language models (LLMs) require alignment to effectively and safely follow user instructions. This process necessitates training an aligned version for every base model, resulting in significant computational overhead. In this work, we propose NUDGING, a simple, training-free algorithm that aligns any base model at inference time using a small aligned model. NUDGING is motivated by recent findings that alignment primarily alters the model's behavior on a small subset of stylistic tokens (e.g., discourse markers). We find that base models are significantly more uncertain when generating these tokens. Building on this insight, NUDGING employs a small aligned model to generate nudging tokens to guide the base model's output during decoding when the base model's uncertainty is high, with only a minor additional inference overhead. We evaluate NUDGING across 3 model families on a diverse range of open-instruction tasks. Without any training, nudging a large base model with a 7×-14×...

Enhancing the Reliability of Split Computing Deep Neural Networks

Thu, 29 Jan 2026 00:00:00 +0000

Artificial intelligence is becoming increasingly popular for IoT applications in safety-critical fields (e.g., autonomous systems and biomedical, robots). Unfortunately, the inference’s workload process alone increases as the model size grows. To meet the computational power limitations of mobile devices running IoT applications, modern services sometimes resort to the Split Computing paradigm. Split Computing divides the inference process of a Neural Network into Head and Tail for their execution in a mobile device and a server, respectively, which also allows the reduction of the overall IoT device’s computational cost. Nonetheless, Split Computing can be used in safety-critical fields where reliability is crucial, especially when mobile devices have computational and cost restrictions. This paper introduces hardening techniques acting on the software to mitigate the effects of hardware faults on Split Computing models. The proposed hardening techniques consist of i) a bounded...

AI-Based Classification of Adversarial Attacks vs. Hardware Fault Corruptions in the Split Computing Context

Thu, 29 Jan 2026 00:00:00 +0000

Split Computing has emerged as a promising paradigm for deploying Deep Neural Networks in Edge and Inter-net of Things systems, enabling inference tasks to be distributed between resource-constrained edge devices and cloud servers. This approach is particularly attractive for autonomous systems, where security and reliability may be critical. However, interme-diate feature maps transmitted between devices are vulnerable to corruption, which may result from intentional adversarial attacks or unintentional hardware faults. Distinguishing whether corruption originates from an external adversary or an inherent system fault is crucial for implementing appropriate counter-measures-reinforcing security mechanisms against attacks or improving system reliability to mitigate the effects of hardware-related faults. To the best of our knowledge, this work is the first to propose a machine learning-based classification mechanism capable of differentiating adversarial attacks from hardware...

Identifying daily-living features related to loneliness: A causal machine learning approach

Tue, 6 Jan 2026 00:00:00 +0000

BACKGROUND: Loneliness is a distressing feeling that influences well-being. Immigrants' experience of acculturation to a new dominant culture places them at risk for maladaptive behaviors and daily rhythms leading to loneliness. Identifying daily-living features that causally influence loneliness is essential for developing effective preventive mental health screening. OBJECTIVE: To identify the important daily living-features related to loneliness for the development of robust screening solutions using causal machine learning for health providers working with first-generation immigrants. METHODS: We monitored 39 immigrants in Finland for 28 days using mobile devices and wearables under free-living conditions. Data included ecological momentary assessments of loneliness, social interactions, physical activity, sleep, and cardiac features. We estimated the average treatment effect (ATE) of each daily-living feature (treatment variable) on loneliness scores (outcome) and validated...

Early detection of coronary artery disease using low-dose CT perfusion: An experimental western fat diet study

Wed, 3 Dec 2025 00:00:00 +0000

PURPOSE: To evaluate changes in myocardial blood flow (MBF) and coronary flow reserve (CFR) over time in a swine model fed a Western diet (WD) using a novel low-dose myocardial CT perfusion technique. MATERIALS AND METHODS: Ten swine with low-density lipoprotein receptor mutations were fed a WD starting at week 0 and imaged after 12, 16, 17, 18, 19, or 23 weeks of WD exposure (mean ± SD: 17.1 ± 3.25 weeks; range 12-23 weeks) using a 320-slice CT scanner under rest and adenosine-induced stress (240 μg/kg/min). Peripheral contrast injection (370 mgI/mL, 0.5 mL/kg, 5 mL/s) with a diluted chaser (30:70 contrast/saline) was followed by bolus tracking and a single-volume scan acquired at peak aortic enhancement (100 kVp, 200 mA). A first-pass analysis model derived MBF (mL/min/g) from bolus-tracking and scan data. Rest and stress MBF were used to compute CFR. Correlations between WD duration and both stress MBF and CFR were assessed....

Assessment of mitochondrial viability under calcium Stress: Insights for mitochondrial transplantation

Thu, 20 Nov 2025 00:00:00 +0000

Mitochondrial transplantation has emerged as a promising cardioprotective strategy for ischemia-reperfusion injury, aiming to restore bioenergetic function by delivering healthy mitochondria to damaged tissue. However, conflicting reports exist regarding whether mitochondria can survive exposure to the calcium-rich extracellular environment, such as the bloodstream, prior to cellular uptake. Resolving this question is essential for advancing the therapeutic use of mitochondria in clinical settings. Isolated mitochondria from L6 rat skeletal muscle cells were incubated with physiologic (1.3 mM), sub-physiologic (0.65 mM), and supraphysiologic (2.6 mM) concentrations of calcium. Mitochondrial membrane potential was assessed using MitoTracker™ Red FM fluorescence, and structural integrity was evaluated using impedance-based Coulter counter analysis over a 12-hour time course. Mitochondria exposed to 1.3 mM calcium retained 90-95 %...

A Reinforcement Learning Framework to Adaptively Schedule Controllers for UAVs Operating Under Harsh Environmental Conditions

Wed, 5 Nov 2025 00:00:00 +0000

In this article, we present a hierarchical supervisory reinforcement learning (RL) framework to achieve precise trajectory tracking for UAV(s) operating in dynamic and complex environments. The UAV is equipped with multiple controllers, and each controller is tuned to provide a desired response under specific environmental conditions. Our objective is to dynamically schedule these controllers in response to abrupt environmental changes. To this end, we develop an RLbased framework for adaptive controller scheduling. We derive sufficient conditions for switching stability and validate our approach through extensive numerical simulations.

Spherical exoskeleton for the measurement of shoulder movement

Wed, 8 Oct 2025 00:00:00 +0000

Spherical exoskeleton for the measurement of shoulder movement

Multiscale analysis of equatorial sclera anisotropy: Revealing discrepancies in fiber orientation and mechanical properties

Thu, 31 Jul 2025 00:00:00 +0000

The sclera, the eye's primary load-bearing tissue, substantially influences the globe's response to intraocular pressure. Although the mechanical properties of the anterior and posterior segments have been extensively studied, the equatorial sclera's properties remain underexplored, limiting our understanding of ocular conditions like myopia, ocular trauma, and glaucoma. Traditional studies that rely solely on fiber orientation to explain scleral mechanics may overlook the tissue's complex biomechanical behavior. To address this gap, we conducted a comprehensive investigation using ultrasonic elastography, optical coherence elastography, and polarizing light microscopy to analyze the equatorial sclera's anisotropic properties. Our findings reveal a counterintuitive result: Mechanical anisotropy in the equatorial sclera contradicts preferred fiber orientation. This integrated approach not only challenges prevailing models of scleral biomechanics but also provides fundamental insights...

Dorsal root ganglion-targeted analgesic delivery for effective relief of neuropathic pain

Thu, 31 Jul 2025 00:00:00 +0000

Neuropathic pain is a devastating experience for patients and its treatment remains challenging. Dorsal root ganglion (DRG) is currently an important therapeutic target and DRG-targeted analgesic delivery through systemic injection is however not reported. Herein, a disintegrin and metalloproteinase protein 8 (ADAM8), a membrane-anchored protein primarily recognized as a cancer biomarker, is found to be de novo and persistently upregulated in the DRG neurons in spared nerve injury (SNI) and chemotherapy-induced neuropathic pain (CINP), two neuropathic pain models with distinct mechanisms. We thus designed a DRG-targeted delivery strategy using lipid nanoparticles (LNPs), aiming to effectively deliver conventional analgesics to the DRG to improve analgesic effect through blocking pain signal transduction from the periphery to central nervous system. In vitro and in vivo results revealed that LNPs extended the duration of action of the free analgesic from less than...

Intracoronary Optical Coherence Tomography: Technological Innovations and Clinical Implications in Cardiology

Thu, 31 Jul 2025 00:00:00 +0000

Purpose of ReviewTo provide the most up-to-date clinical evidence of intracoronary optical coherence tomography (OCT), and clinical implications to guide future imaging research in cardiology.Recent FindingsIntracoronary OCT has demonstrated advanced system performance and high reproducibility in analyzing atherosclerotic lesions. It is an attractive tool due to its capability for functional classification and superior imaging resolution, enabling precise and reliable tissue assessments. Compared to traditional angiography, OCT has been associated with improved long-term clinical outcomes and serves as an effective tool for optimizing stent selection and post-intervention evaluation. The development of OCT variations and the combination of various intravascular imaging modalities further enhance its diagnostic capabilities, allowing a comprehensive assessment of complex vulnerable lesions and improving risk stratification for patients. SummaryCurrent and evolving system development...

Control of brain network dynamics across diverse scales of space and time

Fri, 18 Jul 2025 00:00:00 +0000

The human brain is composed of distinct regions that are each associated with particular functions and distinct propensities for the control of neural dynamics. However, the relation between these functions and control profiles is poorly understood, as is the variation in this relation across diverse scales of space and time. Here we probe the relation between control and dynamics in brain networks constructed from diffusion tensor imaging data in a large community sample of young adults. Specifically, we probe the control properties of each brain region and investigate their relationship with dynamics across various spatial scales using the Laplacian eigenspectrum. In addition, through analysis of regional modal controllability and partitioning of modes, we determine whether the associated dynamics are fast or slow, as well as whether they are alternating or monotone. We find that brain regions that facilitate the control of energetically easy transitions are associated with...

Multiscale analysis of equatorial sclera anisotropy: Revealing discrepancies in fiber orientation and mechanical properties

Mon, 14 Jul 2025 00:00:00 +0000

Photo-induced force microscopy

Mon, 30 Jun 2025 00:00:00 +0000

Photo-induced force microscopy (PiFM) has emerged as a transformative technique in nanoscale imaging, providing insights into the chemical composition and spatial organization of materials at the nanometre scale. PiFM enables innovation in surface science, geological research, biological studies, materials science, photonics and beyond. Compared with other probe-based spectroscopic methods, the nature of tip–sample interaction in PiFM can offer superior spatial resolution and surface sensitivity. This Primer offers the reader an introduction to the fundamentals of PiFM, discusses the configuration of the method, as well as advanced modalities and modifications, such as ultrahigh vacuum and nonlinear techniques. Results and scenarios are summarized, including those in surface chemistry, biology, polymer science and nanophotonics, offering a unique perspective for researchers across multiple disciplines. The Primer concludes with a discussion of PiFM’s limitations and points of...

Chemical Mapping of Nanoparticle–Ligand Interfaces in Optical Nanocavities

Mon, 30 Jun 2025 00:00:00 +0000

Understanding processes in photon-phonon scattering, absorption, and chemical reactions in optical nanocavities is important for single-molecule sensors, single-photon emitters, and photocatalysis. However, the influence of electromagnetic fields, charge transfer, and molecular geometry is challenging to probe by ensemble-averaged spectroscopic techniques over multiple nanocavities. Photoinduced force microscopy (PiFM), which measures photoinduced polarizability under infrared excitation of a sample in the nanocavity between the scanning probe microscopy tip and sample surface, is used here for simultaneous nanoscale topological and chemical characterization. First-principles density functional theory (DFT) simulations of the vibrational spectra of gold nanoparticle surfaces functionalized with benzenedithiol (Au-BDT) elucidate molecular orientation, charge transfer, and oxidation state for understanding molecular and adatom reconfiguration in optical nanocavities in response...

Experimental generation of optimally chiral azimuthally-radially polarized beams

Mon, 30 Jun 2025 00:00:00 +0000

Abstract

We implement a paraxial azimuthally-radially polarized beam (ARPB), a novel class of structured light beams that can be optimal chiral (OC), leading to maximum chirality density at a given energy density. By using vectorial light shaping techniques, we successfully generated a paraxial ARPB with precise control over its features, validating theoretical predictions. Our findings demonstrate the ability to finely adjust the chirality density of the ARPB across its entire range by manipulating a single beam parameter. Although our experimental investigations are primarily focused on the transverse plane, we show that fields whose transverse components satisfy the optimal chirality condition are optimally chiral in all directions, and our results highlight the promising potential of OC structured light for applications in the sensing and manipulation of chiral particles. We show that helicity density is more general than the concept of handedness. This work represents a...

Initial outcomes of novel guideline-directed pharmacotherapy for systemic right heart failure in adults with congenital heart disease

Thu, 19 Jun 2025 00:00:00 +0000

Background: The combination therapy of angiotensin-converting enzyme inhibitors (ACEi) or alternatively angiotensin receptor-neprilysin inhibitors (ARNis), beta-blockers (BBs), mineralocorticoid receptor antagonists (MRAs), and recently sodium-glucose co-transporter 2 inhibitors (SGLT2is) has been hailed as a breakthrough in heart failure treatment for patients with structurally normal hearts, with international guidelines recommending these as first-line therapies ("fantastic four"). However, specific recommendations for adult with congenital heart disease (ACHD) and systemic right ventricle (sRV), who are at heightened risk for heart failure, are largely based on clinical experience or position statements, lacking robust clinical trial data. This study aims to evaluate the effectiveness and tolerability of these medications in ACHD patients with sRV. Methods: This retrospective single-center cohort study included 21 adult patients with sRV and signs of heart failure [6 with...

Preclinical Evaluation of a Growth‐Accommodating Transcatheter Pulmonary Valve System for Young Children

Thu, 19 Jun 2025 00:00:00 +0000

BACKGROUND: Congenital heart defects affect approximately 1% of births in the United States and Europe, with >1 million children in the United States living with congenital heart defects. Many experience abnormalities in the right ventricular outflow tract, often necessitating surgical intervention early in life. However, the initial repairs typically are temporary solutions as many patients will eventually need pulmonary valve replacement to address pulmonary valve regurgitation and prevent right ventricle failure. Addressing progressive pulmonary valve regurgitation, ideally in patients weighing 8 to 10 kg, is critical to prevent right ventricle dysfunction. Transcatheter pulmonary valve replacement currently treats patients weighing at least 20 kg. Unfortunately, smaller children must wait for valve replacement and risk right ventricular dilation. METHODS: To address this challenge, we have developed the IRIS Valve, a growth-accommodating transcatheter pulmonary heart valve...

Real-time cavitation mapping in photo-sono therapy for microvessel removal using Doppler OCT

Wed, 18 Jun 2025 00:00:00 +0000

Photo-sono therapy (PST) combines nanosecond laser pulses with ultrasound bursts to induce cavitation, enabling selective vascular destruction while preserving nearby tissues. Traditional passive cavitation detection (PCD) is often used to evaluate cavitation activity but suffers from limited spatial resolution, complicating integration with PST systems. To address this, we developed a system integrating Doppler optical coherence tomography (OCT) with PST to visualize cavitation dynamics in real-time. The system comprises a 100 kHz VCSEL sweptsource Doppler OCT and a PST module utilizing a 0.5 MHz High-Intensity Focused Ultrasound (HIFU) transducer and a 532 nm nanosecond pulse laser. The system was validated using both blood vessel phantoms and in vivo rabbit ear vessels. Doppler OCT effectively monitored blood flow changes induced by cavitation, with results corroborated by high-speed imaging and PCD. This integrated system facilitates simultaneous monitoring of microvascular...

Precision medicine in vulvar lichen sclerosus: advancing diagnosis and monitoring through optical coherence tomography angiography

Wed, 18 Jun 2025 00:00:00 +0000

Lichen sclerosus (LS) is a chronic inflammatory skin condition that predominantly affects anogenital skin in women. Despite its significant impact, the true prevalence of vulvar LS remains uncertain due to underdiagnosis and underreporting [1]. Studies estimate LS affects up to 3% of postmenopausal women, with an increasing incidence, though it also occurs in premenopausal women and children [2]. This condition is often underserved, and delays in diagnosis can severely impact patients' quality of life, leading to irreversible scarring, vulvar architectural distortion, genitourinary complications, and chronic pain syndromes [3]. Currently, there is limited understanding of LS pathogenesis and no FDA-approved treatments, with lifelong management being the standard approach. Skin biopsies are the gold standard for diagnosing LS; however, they are invasive, particularly in the sensitive vulvar region, and time-consuming. Additionally, approximately 5% of women with LS develop vulvar...

Deep learning-based automated segmentation of airway OCT images acquired during drug-induced sleep endoscopy (DISE)

Wed, 18 Jun 2025 00:00:00 +0000

Obstructive sleep apnea (OSA) is a common upper airway disorder with severe long-term health impacts. There is a critical need for methods that provide quantitative information on dynamic airway collapse during sleep; information not available from sleep studies or conventional Imaging (e.g., CT). We present an alternative minimally invasive approach that combines drug-induced sleep endoscopy (DISE) with optical coherence tomography (OCT) and deep learning. These studies generate a massive volume of data, hence automated methods are needed using deep learning/convolutional neural networks (CNNs) to segment images. This strategy enhances the identification of critical regions prone to collapse, providing a robust tool to optimize treatment for OSA.

Potential-driven electrochemical clearing of ex vivo acidic corneal injuries

Wed, 18 Jun 2025 00:00:00 +0000

Introduction: Acidic corneal injuries pose a serious clinical challenge, often resulting in significant ocular damage and vision impairment. This study evaluates the efficacy of potential-driven electrochemical clearing (P-ECC) for treating acute acidic corneal injuries in ex vivo porcine eye models. Objective: To assess P-ECC effectiveness in clearing acidic corneal injuries, its impact on tissue structure, injury progression, and potential clinical applications. Methods: Ex vivo porcine eyes were subjected to 5M HCl to simulate acidic injuries, followed by irrigation with phosphate buffered saline (PBS). Mobile P-ECC treatment was applied using platinum electrodes (30 seconds per site). Efficacy was assessed through optical coherence tomography (OCT) imaging (∼35 frames per second) and second harmonic generation (SHG) imaging to analyze corneal clarity, thickness, and collagen organization before acid damage, after damage, and after P-ECC treatment. Irrigation with PBS served...

Miniaturized head-mount Doppler optical coherence tomography scope for freely moving mouse

Wed, 18 Jun 2025 00:00:00 +0000

Optical brain imaging has several advantages over other imaging techniques and was used to visualize both the structural and functional aspects of the brain, providing a more complete picture of brain activity. One of the promising techniques is optical coherence tomography (OCT), which uses low-coherence interferometry to obtain three-dimensional depth-resolved imaging of structures. In this research, we present a miniaturized head-mount Doppler OCT system tailored for high-resolution brain imaging in freely moving mice, providing an advanced non-invasive imaging tool in neuroscience research. With a maximum 4×4 mm field of view, 7.4 µm axial resolution, the system offers reliable imaging capabilities. Its compact design and comprehensive imaging capabilities make it well-suited for studying various brain regions and dynamic processes, contributing significantly to our understanding of brain function and pathology.

Characterization of the Coating Layers Deposited onto Curved Surfaces Using a Novel Multi-Nozzle Extrusion Printer

Thu, 8 May 2025 00:00:00 +0000

Over the past two decades, additive manufacturing has advanced significantly, enabling rapid fabrication of functional components across various applications. In medical devices, it has been used for prototyping, prosthetics, drug delivery platforms, and more recently, tissue scaffolding. However, current technologies face challenges, particularly in depositing conformal layers over curved surfaces. This study introduces a novel multi-nozzle extrusion printer concept designed to deposit soft gel layers onto curved surfaces. A custom clearance locking mechanism enhances the printer's ability to achieve conformal coatings on both flat and curved substrates. We investigate key deposition parameters, including displacement volume and nozzle configuration, while comparing two deposition sequences: "Press and Express" and "Express and Press". Our results demonstrate that the "Express and Press" technique yields more uniform, merged conformal layers than the "Press and Express" method....

Pruning functional connections in human induced pluripotent stem cell derived neural networks

Wed, 23 Apr 2025 00:00:00 +0000

The failure of human neuronal stem cells to integrate with brain tissue suggests the need to provide functional cues to modify and re-organize the existing naive network. Understanding how human neural networks respond to external stimuli is crucial to realizing this goal. Here, we stimulate a human induced pluripotent stem cell (hIPSC)-derived neural network on a microelectrode array in a Hebbian fashion to explore the resulting network changes. Short exposure to our stimulation protocol resulted in rapid de-correlation of prior functional connections as well as the emergence of a few strong negative connections. Furthermore, stimulation of the network increased median firing rates with observed network reorganization maintained over the course of 15 days.

Optical Imaging of Cilia in the Head and Neck

Mon, 7 Apr 2025 00:00:00 +0000

Background/Objectives: Cilia are hair-like organelles with various mechanosensory and chemosensory functions. In particular, motile cilia generate directional fluid flow important for multiple processes. Motile ciliopathies have serious clinical implications, including developmental and respiratory disorders. Evaluating the most suitable imaging methods for studying ciliary structure and function has great clinical significance. Methods: Here, we provide an overview of ciliary function, imaging modalities, and applications in ciliopathic diseases. Results: Optical imaging has become a crucial tool for studying ciliary structure and function, providing high-resolution, non-invasive imaging capabilities that are valuable for in vivo applications. Optical coherence tomography (OCT) is well suited for the visualization of ciliary anatomy and quantitative studies of microfluidic flow. Conclusions: A deeper understanding of ciliary biology can lead to novel...

Diagnosis and assessment of vulvar lichen sclerosus (VLS) using optical coherence tomography angiography

Mon, 7 Apr 2025 00:00:00 +0000

Lichen sclerosus (LS) is a chronic inflammatory skin condition that has a predilection for the anogenital skin in women. The true prevalence of vulvar LS is unknown, underdiagnosed, and underreported [1]. Studies have estimated LS affects up to 3% of postmenopausal women, with a rising incidence [2]. The disease also affects premenopausal women and children. Overall, this is an underserved condition and the related delay in diagnosis can have a profound burden on patients’ quality of life and health outcomes, leading to irreversible scarring, infection, vulvar architectural distortion, genitourinary complications, itch, and pain syndromes [3]. There is a limited understanding of disease pathogenesis and no FDA-approved treatment options, with current guidelines recommending lifelong treatment. In the context of Vulvar Lichen Sclerosus, Skin biopsies are considered the standard method for detecting LS. However, they have certain drawbacks, as they are invasive, particularly in...

Nonlinear Nanophotonics: feature issue introduction

Mon, 7 Apr 2025 00:00:00 +0000

We introduce the feature issue of Optical Materials Express on Nonlinear Nanophotonics. This collection highlights recent advances in the design, fabrication, and application of nanophotonic systems that exploit nonlinear optical phenomena, spanning topics from high-harmonic generation and soliton microcombs to plasmon-enhanced emission and mid-infrared nonlinear optics.

Multifunctional Imaging for Monitoring Vaginal Health with Fractional Pixel CO2 Treatment

Mon, 7 Apr 2025 00:00:00 +0000

Monitoring the vaginal health changes is crucial in evaluating the treatment effectiveness for patients with genitourinary syndrome of menopause (GSM). Here we developed a multifunctional OCT/OCTA/OCE system to offer comprehensive analysis of vaginal tissue.

Integrated Phase Resolved Optical Coherence Tomography and Laser Speckle Imaging for Enhanced Cerebral Blood Flow Analysis in Mice under Hypercapnic Stress

Mon, 7 Apr 2025 00:00:00 +0000

Cerebral blood flow dynamics are crucial in understanding neurovascular disease. Here, we developed an integrated imaging system combining Optical Coherence Tomography (OCT) and Laser Speckle Imaging (LSI), offering detailed insights into cerebrovascular hemodynamic changes.

Optical Imaging of Cilia in the Head and Neck

Fri, 4 Apr 2025 00:00:00 +0000

Material characterization and biocompatibility of polycarbonate-based polyurethane for biomedical implant applications

Thu, 27 Mar 2025 00:00:00 +0000

Polycarbonate polyurethane (PCU) resins are widely used in biomedical applications due to their excellent mechanical properties, biocompatibility, and resistance to degradation. The performance of these materials in implantable devices depends on factors such as hardness, molecular weight, and their interactions with cells and tissues. Understanding the relationship between material properties and biological outcomes is essential for optimizing their use in medical devices. In this study, three PCU resins were selected for evaluation as potential polymer implant materials: Chronoflex (CF) 65D, and two Carbothane (CB) samples 95A with different molecular weights. Dynamic mechanical analysis (DMA) revealed that the storage modulus was primarily influenced by the hard domain content, with greater elasticity observed at higher frequencies and lower temperatures. Tensile hysteresis behavior at room temperature was strongly correlated with hardness, with lower hardness samples demonstrating...

Quaternions in Kinematics

Wed, 12 Mar 2025 00:00:00 +0000

Quaternions in Kinematics

Pulmonary regional blood flow: validation of low-dose two-volume dynamic CT perfusion imaging in a swine model

Sat, 1 Mar 2025 00:00:00 +0000

BackgroundWe aimed to validate a low-dose two-volume pulmonary computed tomography (CT) perfusion technique.MethodsFive Yorkshire swine (weight 53.6 ± 2.6 kg) underwent 21 independent CT perfusion acquisitions. Intravenous contrast material (370 mg/mL iodine, 0.5 mL/kg) and saline chaser (0.5 mL/kg) were injected at 5 mL/s for each acquisition. Two-volume and multivolume dynamic CT perfusion data were acquired using a 320-slice CT, with multivolume measurements serving as the reference standard. The two-volume CT perfusion involved a low-dose (50 mA) volume scan before contrast injection and a diagnostic (300 mA) volume scan after bolus-tracking in the main pulmonary artery at the peak contrast enhancement. Multivolume CT perfusion included 15–20 volume scans for blood flow measurement. Paired sample t-test, linear regression, and Bland–Altman analysis compared both global and regional two-volume perfusion measurements to the reference standard. The reproducibility of the two-volume...

Multimodal Pain Recognition in Postoperative Patients: Machine Learning Approach

Thu, 27 Feb 2025 00:00:00 +0000

BACKGROUND: Acute pain management is critical in postoperative care, especially in vulnerable patient populations that may be unable to self-report pain levels effectively. Current methods of pain assessment often rely on subjective patient reports or behavioral pain observation tools, which can lead to inconsistencies in pain management. Multimodal pain assessment, integrating physiological and behavioral data, presents an opportunity to create more objective and accurate pain measurement systems. However, most previous work has focused on healthy subjects in controlled environments, with limited attention to real-world postoperative pain scenarios. This gap necessitates the development of robust, multimodal approaches capable of addressing the unique challenges associated with assessing pain in clinical settings, where factors like motion artifacts, imbalanced label distribution, and sparse data further complicate pain monitoring. OBJECTIVE: This study aimed to develop and evaluate...

Community health workers supporting diverse family caregivers of persons with dementia: Preliminary qualitative results from a randomized home-based study

Fri, 14 Feb 2025 00:00:00 +0000

BACKGROUND AND OBJECTIVES: Culturally diverse informal caregivers of community-dwelling persons with dementia face challenges in accessing dementia care resources due to language barriers and cultural stigmas surrounding dementia. This study presents the perceived intervention experiences of a home-based approach which considers the cultural and linguistic needs of diverse family caregivers in dementia care. The intervention model includes home visits by trained bilingual, non-licensed community health workers (CHWs) whose cultural histories and understandings reflect that of the caregivers. The purpose of the present study was to understand family caregivers' experience in caregiving and their feedback on the intervention, which includes caregiver support through education and skill development. METHODS: The present study thematically analyzed qualitative data from exit interviews with caregivers who participated in a CHW-led, 12-week home visit-based intervention program. RESULTS:...

Arbitrarily programmable wave propagation on a photonic chip

Mon, 10 Feb 2025 00:00:00 +0000

On-chip photonic-neural-network processors promise benefits in both speed and energy efficiency but have not yet reached the scale to compete with electronic processors. The dominant paradigm is to build integrated-photonic processors using discrete components connected by single-mode waveguides. A far more compact alternative is to avoid discrete components and instead sculpt a complex and continuous microphotonic medium in which computations are performed by multimode waves controllably propagating in two dimensions. We show our realization of this approach with a device whose refractive index as a function of space can be rapidly reprogrammed. We demonstrate optical computations much larger and more error-resilient than previous photonic chips relying on discrete components. We argue that beyond photonic-neural-network processors, devices with such arbitrarily programmable index distributions enable the realization of a wide range of photonic functionality.

A Fully Programmable On-Chip Planar Waveguide for Machine Learning