Water sensing methods revealed detection limits of 60 and 30010-4 RIU, while thermal sensitivity measurements, conducted between 25 and 50°C, determined values of 011 and 013 nm/°C for SW and MP DBR cavities, respectively. Plasma-treated surfaces demonstrated the capability to both immobilize proteins and detect BSA molecules at 2 g/mL in phosphate-buffered saline. This process resulted in a 16nm resonance shift, fully recoverable to baseline levels after removing the proteins with sodium dodecyl sulfate, using a MP DBR device. The results point toward a promising advancement in active and laser-based sensors, utilizing rare-earth-doped TeO2 in silicon photonic circuits, which can then be coated in PMMA and functionalized via plasma treatment for label-free biological sensing.
Deep learning-powered high-density localization significantly accelerates single-molecule localization microscopy (SMLM). Deep learning methods for localization demonstrate faster data processing and higher accuracy than traditional high-density localization techniques. However, the existing high-density localization methods relying on deep learning are not yet sufficiently rapid to support real-time processing of extensive raw image collections. The U-shaped network structures likely contribute significantly to this computational burden. This paper proposes FID-STORM, a high-density localization method based on an improved residual deconvolutional network architecture for the real-time processing of raw image data. FID-STORM stands out by employing a residual network to extract pertinent features from the original, low-resolution raw images, a departure from the approach using a U-shaped network on pre-processed, interpolated images. Using TensorRT model fusion, we also aim to further accelerate the inference process of the model. Additionally, a direct GPU processing of the sum of localization images is implemented to yield an incremental speed increase. Experimental and simulated data demonstrated that the FID-STORM method can process 256256-pixel frames at 731 milliseconds using an Nvidia RTX 2080 Ti, exceeding the typical 1030-millisecond exposure time. This speed facilitates real-time data processing in high-density stochastic optical reconstruction microscopy (SMLM). Likewise, FID-STORM outperforms the well-known interpolated image-based approach, Deep-STORM, by a substantial 26 times in processing speed, without compromising the reconstruction accuracy. A supplementary ImageJ plugin was included with our new method.
Polarization-sensitive optical coherence tomography (PS-OCT) imaging, specifically degree of polarization uniformity (DOPU) imaging, offers potential retinal disease biomarkers. This method brings into focus abnormalities in the retinal pigment epithelium, which may not be readily evident from the OCT intensity images alone. While conventional OCT systems are less intricate, a PS-OCT system demonstrates a higher level of complexity. Our approach, leveraging a neural network, estimates DOPU from typical OCT scans. To generate DOPU images, a neural network was trained using DOPU images as the learning target from single-polarization-component OCT intensity images. Following the neural network's synthesis of DOPU images, a direct comparison of clinical findings was undertaken between the authentic and synthesized versions of the DOPU. Analysis of 20 cases with retinal diseases shows a noteworthy agreement in RPE abnormality findings, yielding a recall of 0.869 and a precision of 0.920. Five healthy volunteers exhibited no anomalies in either the synthesized or ground truth DOPU images. The DOPU synthesis method, based on neural networks, shows promise in enhancing retinal non-PS OCT capabilities.
Difficulty in measuring altered retinal neurovascular coupling, a potential contributing factor in diabetic retinopathy (DR) progression, stems from the insufficient resolution and narrow field of view typically encountered in functional hyperemia imaging. A novel approach to functional OCT angiography (fOCTA) is presented, offering 3D visualization of retinal functional hyperemia at the resolution of single capillaries throughout the entire vascular network. UCLTRO1938 Using 4D synchronized OCTA, flicker light stimulation evoked functional hyperemia, which was precisely quantified and extracted from each capillary segment and stimulation period in the time series. High-resolution fOCTA demonstrated retinal capillary hyperemia, notably in the intermediate plexus, in normal mice. A significant loss of functional hyperemia (P < 0.0001) was observed early in diabetic retinopathy (DR), with limited visible retinopathy, yet was reversed by aminoguanidine treatment (P < 0.005). The heightened functional activity of retinal capillaries holds considerable promise as a highly sensitive biomarker for early diabetic retinopathy, while fOCTA retinal imaging will provide new understanding of the underlying disease mechanisms, screening criteria, and effective treatments for this early-stage disorder.
Vascular alterations, strongly associated with Alzheimer's disease (AD), have seen a surge in recent interest. In vivo, longitudinal optical coherence tomography (OCT) imaging was conducted on an AD mouse model without labeling. Using OCT angiography and Doppler-OCT, a detailed analysis of the temporal dynamics in vasculature and vasodynamics was conducted, focusing on the same individual vessels over time. In the AD group, there was an exponential reduction in vessel diameter and blood flow before 20 weeks, which preempted the cognitive decline observed at 40 weeks of age. It's noteworthy that, for the AD group, diameter changes exhibited a more prominent impact on arterioles compared to venules, yet this preferential effect wasn't observed in blood flow changes. On the other hand, three mouse groups undergoing early vasodilatory intervention demonstrated no appreciable alterations in vascular integrity or cognitive function, when measured against the wild-type group. population genetic screening We ascertained the existence of early vascular alterations and their correlation with cognitive impairment in AD patients.
Pectin, a heteropolysaccharide, is the substance responsible for the structural firmness of terrestrial plant cell walls. The application of pectin films to the surfaces of mammalian visceral organs results in a strong, physical binding to the organ's surface glycocalyx. genetic pest management The entanglement of pectin polysaccharide chains with the glycocalyx, contingent upon water, is a plausible mechanism for pectin adhesion. A deeper comprehension of the fundamental principles of water movement within pectin hydrogels is vital for medical uses, including the sealing of surgical wounds. We present an analysis of water transport within hydrating pectin films in the glass phase, focusing specifically on the water concentration at the interface between the pectin and glycocalyx. To understand the pectin-tissue adhesive interface, we leveraged label-free 3D stimulated Raman scattering (SRS) spectral imaging, circumventing the confounding issues of sample fixation, dehydration, shrinkage, or staining.
Combining high optical absorption contrast with deep acoustic penetration, photoacoustic imaging non-invasively elucidates structural, molecular, and functional aspects of biological tissue. Various practical restrictions inherent to photoacoustic imaging systems often result in challenges, such as convoluted system arrangements, lengthy imaging durations, and suboptimal image quality, collectively impeding clinical translation. The use of machine learning in photoacoustic imaging allows for improved performance, reducing the formerly strict demands imposed on system setup and data acquisition. Diverging from previous reviews of learned techniques in photoacoustic computed tomography (PACT), this review emphasizes the use of machine learning to tackle the constraints of limited spatial sampling in photoacoustic imaging, including those associated with limited view and undersampling. Based on a synthesis of their respective training data, workflow, and model architecture, we present a summary of the key PACT works. Crucially, our work also presents recent, limited sampling results for the alternative photoacoustic imaging approach: photoacoustic microscopy (PAM). Machine learning's application to photoacoustic imaging produces improved image quality, even with limited spatial sampling, positioning it for potential low-cost and user-friendly clinical deployments.
The full-field, label-free imaging of blood flow and tissue perfusion is accomplished by the use of laser speckle contrast imaging (LSCI). Its presence has become evident in the clinical environment, including the surgical microscope and endoscope Even with the enhanced resolution and SNR in traditional LSCI, clinical translation presents a persistent challenge. This study employed a random matrix approach to statistically distinguish single and multiple scattering components in LSCI data, achieved through dual-sensor laparoscopy. Laboratory-based in-vitro tissue phantom and in-vivo rat experiments were undertaken to evaluate the newly developed laparoscopy. rmLSCI, a random matrix-based LSCI, offers crucial blood flow information for superficial tissue and tissue perfusion information for deeper tissue, proving particularly helpful in intraoperative laparoscopic surgery. The new laparoscopy's capabilities include simultaneous display of rmLSCI contrast images and white light video monitoring. Experiments on pre-clinical swine were further employed to demonstrate the quasi-3D reconstruction functionality of the rmLSCI method. The potential of the rmLSCI method's quasi-3D capability extends beyond its initial applications, promising advancements in clinical diagnostics and therapies utilizing gastroscopy, colonoscopy, and surgical microscopes.
Patient-derived organoids (PDOs) are instrumental in predicting cancer treatment outcomes, serving as excellent tools for personalized drug screening. Nonetheless, existing techniques for effectively measuring drug responsiveness remain restricted.