Imaging Mode Research Articles

Research on puncture classification method of seed implantation robot based on force/image model

This article focuses on the use of a puncture classification method for prostate cancer seed implantation robots. To address the limitations of seed implantation surgery, different tissues in the human body are punctured and classified to improve the precision and success rate of seed implantation. This paper discusses an information fusion sensing technique that can be used in seed implantation surgery, which senses the real-time state of the puncture needle by fusing force and image modes and dramatically improves puncture accuracy and surgical tolerance. In addition, considering the multiscale feature problem of the image recognition process, this paper improves the YOLOv8 model by adding a global attention mechanism (GAM_Attention) to the backbone of the model, which significantly improves the image recognition success rate. Then, datasets of the puncture force and real-time puncture images were produced through puncture experiments. Preliminary puncture experiments with different models were completed, and the experimental results showed that the classification method improved the classification accuracy. The accuracy of seed implantation is improved by this method, which may provide a new idea for deep learning in seed implantation modality perception.

Velocimetry of GHz elastic surface waves in quartz and fused silica based on full-field imaging of pump–probe reflectometry

This study reports an imaging method for gigahertz surface acoustic waves in transparent layers using infrared subpicosecond laser pulses in the ablation regime and an optical pump–probe technique. The reflectivity modulations due to the photoelastic effect of generated multimodal surface acoustic waves were imaged by an sCMOS camera illuminated by the time-delayed, frequency-doubled probe pulses. Moving the delay time between 6.0nsto11.5ns, image stacks of wave field propagation were created.Two representative samples were investigated: wafers of isotropic fused silica and anisotropic x-cut quartz. Rayleigh (SAW) and longitudinal dominant high-velocity pseudo-surface acoustic wave (HVPSAW) modes could be observed and tracked along a circular grid around the excitation center, allowing the extraction of angular profiles of the propagation velocity. In quartz, the folding of a PSAW was observed. A finite element simulation was developed to predict the measurement results. The simulation and measurement were in good agreement with a relative error of 2% to 5%.These results show the potential for fast and full-field imaging of laser-generated ultrasonic surface wave modes, which can be utilized for the characterization of thin transparent samples such as semiconductor wafers or optical crystals in the gigahertz frequency range.

Role of Ultrasound in Diagnosis of Fibrocystic Breast Disease

Background: Fibrocystic breast disease is the most typical benign breast disease, which is seen in women worldwide with features of pain and feeling of nodules. Its diagnosis is based on clinical symptoms, ultrasound, mammography, and in doubt cases, biopsy is indicated. For assessment of the breast, we clinically examined the breast, axilla, and both supra and infraclavicular regions for lymph node assessment, followed by ultrasound examination. Detection of lesions in any breast quadrant assessed by BIRADs, Breast Imaging Reporting, and Data System grouped in five brackets. Scanning by sonography using B-mode and Doppler study was improved for detecting and characterizing benign and malignant lesions. Objective: To assess a breast lesion by ultrasound with features suggestive of a benign or malignant nature. Method: This study included 210 women aged 20 - 45 who visited a clinic from October 2020 to April 2022 and were examined by ultrasound machine Samsung HS50 (KOREA) with an LA3-14AD probe. B-mode images obtained detection of the lesion, and we also used Doppler ultrasound for assessment of the vascularity of the lesion. The BI-RADS system was used for the categorization of all findings. Result: In 210 women, complaints of lumps were involved in our study. Imaging by B-mode ultrasound using the Doppler study assesses the vascularity of the lesion and provides more characterization of benign and malignant lesions. By B–mode imaging, 99 patients had regular ultrasound study, and 79 patients had simple cysts that appeared well defined, had familiar outlines, and had an anechoic rounded or oval shape with posterior enhancement. Twenty-eight patients with fibroadenoma visualized as round or oval-shaped hypoechoic lesions horizontally oriented to the planes of the breast with lateral shadowing. 2 patients had complex cysts that appear as well-defined, irregular outlines, rounded shape, a thick wall with internal echoes with posterior enhancement. 2 patients have a malignant lesion that appears ill-defined rough outline vertically oriented with breast planes and show posterior shadowing. Conclusion: Ultrasound was established as the most suitable imaging modality for the categorization of breast lesions and exclusion of malignancy, which is helpful for evading unnecessary biopsies.

STONKS: Quasi-real time XMM-Newton transient detection system

Over recent decades, astronomy has entered the era of massive data and real-time surveys. This is improving the study of transient objects -- although they still contain some of the most poorly understood phenomena in astrophysics, as it is inherently more difficult to obtain data to constrain the proposed models. In order to help detect these objects in their brightest state and build synergies with multi-wavelength real-time surveys, we have built a quasi-real time automatic transient detection system for the XMM-Newton pipeline: the Search for Transient Objects in New detections using Known Sources (STONKS) pipeline. STONKS detects long-term X-ray transient events by automatically comparing new XMM-Newton detections to any available archival X-ray data at this position, sending out an alert if the variability between observations (defined as the ratio between the maximum flux and the minimum flux or upper limit) is over 5. This required an initial careful cross-correlation and flux calibration of various X-ray catalogs from different observatories ( XMM-Newton Chandra Swift ROSAT, and eROSITA). A Bayesian framework was put into place to solve any ambiguous associations. We also systematically computed the XMM-Newton upper limits at the position of any X-ray source covered by the XMM-Newton observational footprint, even without any XMM-Newton counterpart. The behavior of STONKS was then tested on all 483 observations performed with imaging mode in 2021. Over the 2021 testing run, STONKS provided a daily alert rate of 0.7$^ $ alerts per day, about 80<!PCT!> of them corresponding to serendipitous sources. Among the detected variable serendipitous sources, there are: several highly variable active galactic nuclei (AGNs) and flaring stars, as well as new X-ray binary and ultra-luminous X-ray source candidates, some of which are present here. STONKS also detected targeted tidal disruption events, ensuring its ability to detect other serendipitous events. As a byproduct of our method, the archival multi-instrument catalog contains about one million X-ray sources, with 15<!PCT!> of them involving several catalogs and 60<!PCT!> of them having XMM-Newton (pointed or slew) upper limits. STONKS demonstrates a great potential for revealing future serendipitous transient X-ray sources, providing the community with the ability to follow-up on these objects a few days after their detection with the goal of obtaining a better understanding of their nature. The underlying multi-instrument archival X-ray catalog will be made available to the community and kept up to date with future X-ray data releases.

Cardiopulmonary effects of apneustic anesthesia ventilation in anesthetized pigs: a new mode of ventilation for anesthetized veterinary species

ObjectiveTo compare the cardiopulmonary effects of apneustic anesthesia ventilation (AAV) and conventional mechanical ventilation (CMV) in anesthetized pigs and to describe a new mode of ventilation for anesthetized veterinary species.Study designRandomized, crossover design without washout.AnimalsTwelve healthy, female white Landrace pigs.MethodsFollowing ketamine-midazolam premedication and anesthetic induction with propofol, the trachea was intubated, and each pig was positioned in dorsal recumbency. Anesthesia was maintained with propofol and sufentanil infusions. Pigs were instrumented and their lungs were sequentially ventilated with each mode, in random order, for 1 h according to predefined criteria [fraction of inspired oxygen (FiO2) = 0.21, 10 mL kg−1 tidal volume (VT), and arterial carbon dioxide tension (PaCO2) within 40–45 mmHg]. Cardiopulmonary data were collected at baseline, 30 and 60 min. In 8 pigs, thoracic computed tomography (CT) was performed following the 60 min time point for each mode of ventilation and images were analyzed to quantify lung aeration. The effects of ventilation mode, time, and order were analyzed using repeated measures ANOVA. Paired t-tests were used to compare lung aeration between modes. Significance was defined as p < 0.05.ResultsData from 12 pigs were analyzed. A significant effect of mode was found for heart rate, mean arterial pressure (MAP), pulmonary artery occlusion pressure, cardiac index (CI), stroke volume index, systemic vascular resistance, pulmonary vascular resistance, oxygen delivery index (DO2I), oxygen extraction ratio (O2ER), VT, arterial oxygen tension, arterial hemoglobin saturation, PaCO2, end-tidal carbon dioxide tension, alveolar dead space (VDalv/VTalv), venous admixture (Q.s/Q.t), mean airway pressure, and dynamic compliance index (CRSI). Order effects were also observed for some cardiovascular and respiratory variables. For the eight pigs that underwent thoracic CT, AAV resulted in significantly larger proportions of normally and hyperaerated lung while CMV resulted in larger proportions of hypoaerated and atelectatic lung.ConclusionsIn dorsally recumbent anesthetized pigs, ventilated with FiO2 = 0.21, both modes of ventilation supported adequate oxygenation while AAV resulted in higher CRSI, and lower VDalv/VTalv and Q.s/Q.t, compared with CMV. AAV was also associated with lower MAP, CI, and DO2I and higher O2ER compared with CMV. Further investigation of AAV in anesthetized animals is warranted.

Planar and volumetric imaging dosimetry for longitudinal projection extended cone beam CT based adaptive radiotherapy

BackgroundThe objective of this study is to provide a detailed insight into the broad beam dosimetric characteristics of two commercial cone beam computed tomography (CBCT) imaging systems to complement the longitudinal projection extended CBCT based image guided adaptive radiotherapy (IGART). Methods and materialsThe absolute dose calibration, planar and volumetric dosimetric characteristics of two CBCT imaging systems viz., the Clinac 2100 C/D On-Board Imager (OBI) and the TrueBeam X-ray Imaging system (XI) (Varian Medical Systems, Palo Alto, CA) were investigated. Reference dosimetry specific to volumetric CBCT imaging mode was performed as per American Association of Physicists in Medicine (AAPM) task group (TG) 61 protocol using calibrated 0.6 cc Farmer ionization chamber (30010, PTW Dosimetry Company, Germany). The rotational planar and volumetric dosimetry was performed after calibrating the OCTAVIUS 1500 detector array as a mere photon detector, with and without the detachable hemisphere of 4D Modular phantom. ResultsThe absolute dose of half-fan XI CBCT was found to be 1.2 times lower when compared to OBI CBCT. The abutting kV cone beam dosimetry specific to dual-scan CBCT fusion technique showed a wider in-plane profile for the OBI system when compared to the XI system, due to an additional field opening of 3.4 cm used for half-fan mode in the former. The reconstructed volumetric imaging dose distribution specific to half-fan geometry and dynamic movement of gantry, brought to light valuable details about the kV dose distribution. ConclusionThe planar and 3D imaging dosimetry reported in this study paves the way for the integration of volumetric imaging dose reconstruction capabilities during high precision radiotherapy to demonstrate a complete picture of the total dose delivered to the patient during the planned course of IGART.

Testing the generalizability and effectiveness of deep learning models among clinics: sperm detection as a pilot study

BackgroundDeep learning has been increasingly investigated for assisting clinical in vitro fertilization (IVF). The first technical step in many tasks is to visually detect and locate sperm, oocytes, and embryos in images. For clinical deployment of such deep learning models, different clinics use different image acquisition hardware and different sample preprocessing protocols, raising the concern over whether the reported accuracy of a deep learning model by one clinic could be reproduced in another clinic. Here we aim to investigate the effect of each imaging factor on the generalizability of object detection models, using sperm analysis as a pilot example.MethodsAblation studies were performed using state-of-the-art models for detecting human sperm to quantitatively assess how model precision (false-positive detection) and recall (missed detection) were affected by imaging magnification, imaging mode, and sample preprocessing protocols. The results led to the hypothesis that the richness of image acquisition conditions in a training dataset deterministically affects model generalizability. The hypothesis was tested by first enriching the training dataset with a wide range of imaging conditions, then validated through internal blind tests on new samples and external multi-center clinical validations.ResultsAblation experiments revealed that removing subsets of data from the training dataset significantly reduced model precision. Removing raw sample images from the training dataset caused the largest drop in model precision, whereas removing 20x images caused the largest drop in model recall. by incorporating different imaging and sample preprocessing conditions into a rich training dataset, the model achieved an intraclass correlation coefficient (ICC) of 0.97 (95% CI: 0.94-0.99) for precision, and an ICC of 0.97 (95% CI: 0.93-0.99) for recall. Multi-center clinical validation showed no significant differences in model precision or recall across different clinics and applications.ConclusionsThe results validated the hypothesis that the richness of data in the training dataset is a key factor impacting model generalizability. These findings highlight the importance of diversity in a training dataset for model evaluation and suggest that future deep learning models in andrology and reproductive medicine should incorporate comprehensive feature sets for enhanced generalizability across clinics.

Fingerprint recognition using convolution neural network with inversion and augmented techniques

Fingerprints are considered as one of the most important and prominent feature for an individual identification. Due to their consistency and reliability in biometric feature identification, they are most widely used for biometric recognition systems. In these systems, the relevant feature extraction plays important role in achieving required classification accuracy. In recent time, deep learning techniques are being used for fingerprint recognition with more accuracy and efficient results. Major difficulty which has been reported in previous researches, is the limited size of samples. Therefore, we propose two approaches, inversion and multi augmentation to augment the sample size with newly generated images for each feature map. Besides this, multiple networks are used simultaneously for feature extraction from newly generated images in parallel mode. Deep neural network architectures are used with proposed inversion methods and multi augmentation methods to classify the samples of fingerprints for personnel identification and verification. Pre-trained deep convolutional models like VGG16, VGG19, ResNet50 and InceptionV3 are fine-tuned with new processed fingerprint images for feature extraction and classification. The collective samples of fingerprints have been classified into 10 classes. The simulation results have been obtained with different optimizers and it has been observed that VGG 19 model exhibits the accuracies of 88 % and 93 % with inversion and multi augmentation approaches respectively. Whereas, VGG16 model exhibits 93 % with inversion approach and 97 % with multi augmentation approach. Thus, the proposed approach exhibits the accuracy up to 97 % with VGG16 model which is significantly much higher than that of any other model with the same dataset FVC2000_DB4.

Endoscopic evaluation of gastric mucosal alterations in patients with chronic heart failure II-III nyha functional class utilizing advanced endoscopic techniques

Objective: To assess the alterations of gastric mucosa, its pathomorphological and functional characteristics in patients with complete erosions suffering from chronic heart failure II-III NYHA functional class. Materials and Methods: 185 patients with complete erosions comprised the main group, while the control group consisted of 183 patients with incomplete erosions of the stomach. Patients in both groups had chronic heart failure II-III NYHA functional class. All patients underwent esophagogastroduodenoscopy with white light imaging (WLI), narrow-band imaging (NBI), and ZOOM modes, as well as biopsy sampling followed by pathomorphological examination, determination of Helicobacter pylori presence, and endoscopic pH-metry. The diagnosis of chronic heart failure was established based on anamnestic data and the results of instrumental and functional diagnostic methods, including electrocardiography (ECG), echocardiography, Holter monitoring of ECG, stress echocardiography, and coronary angiography. Results: The study utilized the classification of gastric erosive lesions by K. Toljamo (2012), according to which in the main group, mature erosions subtype Ia were detected in 83.8% of cases, while immature extensive erosions subtype Ib were found in 16.2%. In combination with haemorrhagic erosions (type III), complete erosions were detected in 12.6% of cases, while with incomplete erosions of type II, they were found in 11.4%. The combination of complete erosions with erosive prepyloric changes (type IV) was identified in 8.7%. In the control group, gastric erosive lesions were mainly represented by type III (41%) and type IV (38.8%). Based on the analysis of endoscopic changes in the gastric mucosa using WLI, NBI, and ZOOM modes, the most characteristic visual changes were identified for each type and subtype of erosive gastric mucosa alterations. In patients with chronic heart failure II-III NYHA functional class, gastritis was noted in 75.1% of cases in the main group and in 58.5% in the control group. Helicobacter pylori infection of weak degree was determined in 40.5% in the main group and 37.7% in the control group. Evaluation of endoscopic pH-metry showed predominantly hypochlorhydria in both groups - 70.8% in the main group and 48.6% in the control group. Conclusion: By comparing the macroscopic features of various gastric erosive lesions in WLI, NBI, and ZOOM modes according to the classification by K. Toljamo (2012), the most characteristic signs for each type and subtype were identified. High prevalence of gastritis was established among patients with chronic heart failure II-III NYHA functional class.

Multi-purpose InSTRument for Astronomy at Low-resolution: MISTRAL at the Observatoire de Haute-Provence

Multi-purpose InSTRument for Astronomy at Low-resolution (MISTRAL) is the new Faint Object Spectroscopic Camera mounted at the folded Cassegrain focus of the 1.93m telescope of the Haute-Provence Observatory (OHP). We describe the design and components of the instrument and give some details about its operation. We emphasize in particular the various observing modes and the performance of the detector. A short description of the working environment is also provided. Various types of objects, including stars, nebulae, comets, novae, and galaxies, have been observed during various test phases to evaluate the performance of the instrument. The instrument covers the range of 4000 to 8000 AA with the blue setting, or from 6000 to 10000 AA with the red setting, at an average spectral resolution of 700. Its peak efficiency is about 22$<!PCT!>$ at 6000 AA . In spectroscopy, a limiting magnitude of rsim 19.5 can be achieved for a point source in one hour with a signal-to-noise ratio of 3 in the continuum (and better when emission lines are present). In imaging mode, limiting magnitudes of 20-21 can be obtained in 10-20mn (with average seeing conditions of 2.5 arcsec at the OHP). The instrument is very user-friendly and can be put into operations in less than 15mn (rapid change-over from the other instrument in use) if required by the science (e.g. for gamma-ray bursts). Some first scientific results are described for various types of objects, and in particular, for the follow-up of gamma-ray bursts. While some further improvements are still under way, in particular, to facilitate the switch from blue to red setting and add more grisms or filters, MISTRAL is ready for the follow-up of transients and other variable objects, in the soon-to-come era of the Space-based multi-band astronomical Variable Objects Monitor (SVOM) satellite and of the Rubin telescope, for instance.

Direct investigations of interactions between nucleolins and aptamers on pancreatic cancer and normal cells by atomic force microscopy

Nucleolin is overexpressed on the surface of pancreatic cancer cells and are regarded as the remarkable therapeutic target. Aptamers are capable of binding the external domain of nucleolin on the cell surface with high affinity and specificity. But nucleolin has not been localized on pancreatic cancer cells at very high spatial resolution, and the interactions between nucleolin and aptamers have not been investigated at very high force resolution level. In this work, nucleolin was localized on pancreatic cancer and normal cells by aptamers (9FU-AS1411-NH2, AS1411-NH2 and CRONH2) in Single Molecule Recognition Imaging mode of Atomic Force Microscopy. There are plenty of nucleolin on the surfaces of pancreatic cancer cells (area percentage about 5 %), while there are little nucleolin on the surfaces of normal cells. The interactions between three types of aptamers and nucleolins on the surfaces of pancreatic cancer cells were investigated by Single Molecule Force Spectroscopy. The unbinding forces of nucleolins-(9FU-AS1411-NH2) are larger than nucleolins-(AS1411-NH2). The dissociation activation energy on nucleolin-(9FU-AS1411-NH2) is higher than nucleolin-(AS1411-NH2), which indicates that the former complex is more stable and harder to dissociate than the later complex. There are no unbinding forces between nucleolin and CRONH2. All these demonstrate that nucleolin was localized on pancreatic cancer and normal cells at single molecule level quantitatively, and the interactions (unbinding forces and kinetics) between nucleolin and aptamers were studied at picoNewton level. The approaches and results of this work will pave new ways in the investigations of nucleolin and aptamers, and will also be useful in the studies on other proteins and their corresponding aptamers.

Hybrid-index-based array configuration optimization for Michelson interferometric imaging

Array configuration design is a critical issue for a high quality of the snapshot point spread function (PSF) and restored image in Michelson imaging interferometer. In classic design, the optimized configurations usually address the few specifications and single objective, which is unable to balance the requirements of both non-redundancy and sampling distribution. In this paper, we formalize mathematically the composite metric to trade-off the multiple demands of observation, and propose the hybrid-index-based array layout optimization strategy. The simulation results demonstrate that, in comparison with the typical distribution, the optimized array using the proposed optimization framework enables the acquisition of more comprehensive spectrum information while utilizing an equal number of apertures, providing superior imaging quality in different observation situations. Furthermore, the designed optimized array masks and the compared conventional array masks were fabricated and used for our experimental validation, further verifying the feasibility of this strategy. This array configuration optimization framework may not only find applications to Michelson interferometric imaging, but also provide a positive impact on all u-v sampling-based imaging modes, including radio interferometry, magnetic resonance imaging, and photonic integrated interferometric imaging.

TransEBUS: The interpretation of endobronchial ultrasound image using hybrid transformer for differentiating malignant and benign mediastinal lesions

The purpose of this study is to establish a deep learning automatic assistance diagnosis system for benign and malignant classification of mediastinal lesions in endobronchial ultrasound (EBUS) images. EBUS images are in the form of video and contain multiple imaging modes. Different imaging modes and different frames can reflect the different characteristics of lesions. Compared with previous studies, the proposed model can efficiently extract and integrate the spatiotemporal relationships between different modes and does not require manual selection of representative frames. In recent years, Vision Transformer has received much attention in the field of computer vision. Combined with convolutional neural networks, hybrid transformers can also perform well on small datasets. This study designed a novel deep learning architecture based on hybrid transformer called TransEBUS. By adding learnable parameters in the temporal dimension, TransEBUS was able to extract spatiotemporal features from insufficient data. In addition, we designed a two-stream module to integrate information from three different imaging modes of EBUS. Furthermore, we applied contrastive learning when training TransEBUS, enabling it to learn discriminative representation of benign and malignant mediastinal lesions. The results show that TransEBUS achieved a diagnostic accuracy of 82% and an area under the curve of 0.8812 in the test dataset, outperforming other methods. It also shows that several models can improve performance by incorporating two-stream module. Our proposed system has shown its potential to help physicians distinguishing benign and malignant mediastinal lesions, thereby ensuring the accuracy of EBUS examination.

Ultrasparse Ultrasonic Synthetic Aperture Focus Imaging by Passive Sensing.

Ultrasonic synthetic aperture focus techniques (SAFTs) using less than the total number of available array elements to transmit ("sparse" transmissions) have been recently used in both medical imaging and industrial nondestructive testing (NDT) imaging to increase test speed and simplify multiplexer hardware. The challenge of sparse arrays is to obtain a reasonable image quality given the reduced transmitter-receiver combinations available to the beamforming process. This article proposes a "ultrasparse" SAFT method that employs a minimum number of transmitter elements (from one to four elements only) to obtain an entire full-matrix capture (FMC) set of waveforms. Specifically, a "virtual" FMC is obtained from normalized cross-power spectra between each array element pair in an implementation of "passive" ultrasonic sensing. In order to maintain high image quality without sacrificing imaging speed (e.g., applying a minimal initial time delay and keeping a short time recording window), several key steps have to be taken in this "passive" imaging mode, specifically: 1) the use of carefully designed segment-averaged normalized cross-power spectrum (NCPS) for robust passive reconstruction of the ultrasonic impulse response function (IRF) between two receivers; 2) the use of both the causal and acausal portions of the passively reconstructed IRFs; and 3) the compounding of multiple wave modes in the beamforming process. These steps also ensure the elimination of the near-field blind zone hence potentially enabling near-field imaging. The article first reviews the theory of passive IRF reconstruction between two receivers, comparing time-averaged cross correlation versus segment-averaged NCPS, and then demonstrates the application to ultrasparse SAFT FMC imaging of drilled holes in an aluminum block using a linear transducer array where only one to four elements are used in transmission.

Single-cell analysis using Imaging Mass Cytometry spatially resolves immune activity in neurodegenerative brain pathology

Abstract Immune response plays a significant role in the progression of neurodegenerative diseases (NDs) such as Parkinson’s disease (PD), Alzheimer’s disease (AD), and multiple sclerosis (MS). It is paramount to quantify the immune and structural spatial microenvironment of ND brain using research approaches that resolve tissue at a single-cell level. Imaging Mass Cytometry™ (IMC™) is a spatial biology technique that provides quantitative phenotypic evaluation of 40-plus markers. We report the application of two new IMC imaging modes with 40-marker panels for ND research. Tissue mode (TM) was applied to perform a scan of the entire tissue followed by pixel-based analysis (PBA) to uncover spatial distribution of relevant markers. Preview mode (PM) was applied to sample the tissue at low resolution, improving informed selection of areas for high-resolution cell mode (CM) imaging on the same slide. Using TM with PBA, we quantified the spatial distribution of immune cells in tissue compartments of ND tissues. PM and CM highlighted MS lesions devoid of myelinization and a network of α-synuclein in PD tissue. Single-cell analysis identified heterogeneity of amyloid precursor protein aggregates in AD that encompassed total and phosphorylated species of tau and phosphorylated α-synuclein. Overall, whole slide imaging techniques using IMC provide quantitative immunological and structural insights into the spatial biology of ND. For Research Use Only. Not for use in diagnostic procedures.

Prenatal diagnosis of interrupted aortic arch using high-definition flow render mode and spatiotemporal image correlation.

To evaluate the clinical utility of two dimensional (2D) ultrasound combined with spatiotemporal image correlation (STIC) in diagnosing interrupted aortic arch (IAA) in fetal life. A total of 53 cases of fetal IAA were diagnosed using 2D ultrasound combined with STIC, and 53 normal fetuses of the same gestational week were selected. These cases were retrospectively analyzed to assess the utility of employing 2D ultrasound combined with STIC in the diagnosis of IAA. 2D ultrasound combined with STIC detected 22 cases of type A IAA, 24 cases of type B IAA, and seven cases of type C IAA. Furthermore, combining 2D ultrasound with STIC enabled dynamic visualization of the IAA, aiding in prenatal diagnosis. The diagnostic coincidence rate of IAA was found to be higher in the HD-flow combined with STIC than that in the 2D combined with HD-flow. HD-flow combined with STIC can assist in diagnosing fetal IAA, and this technique has important clinical value.

Detecting immune activity in human tumors with novel high-throughput whole slide imaging approaches using Imaging Mass Cytometry.

Abstract Deciphering the spatial biology of the tumor immune microenvironment (TIME) has potential to inform clinical and translational researchers about the likelihood of immunotherapy success. Imaging Mass Cytometry™ (IMC™) is a spatial biology imaging technique that enables deep characterization of the TIME while fully retaining spatial features of tissues using 40-plus markers simultaneously. We developed two new whole slide imaging methods for IMC. Tissue mode (TM) rapidly acquires an image of the whole tissue that can be used for quantitative analysis of spatial biology. Preview mode (PM) samples the entire tissue at predefined spacing to rapidly capture a low-resolution image of all expressed markers, improving informed identification of areas for high-resolution cell mode (CM) imaging on the same slide. Tumor tissues were stained using a 40-marker panel comprised of the Maxpar™ Human Immuno-Oncology IMC Panel Kit, designed for tumor and immune cell profiling. TM imaging in combination with pixel-based analysis quantified tissue areas containing high or low abundance of myeloid and lymphoid immune, tumor and stromal cell compartments. PM in combination with CM imaging followed by single-cell analysis on selected tumor regions identified cell populations with varying activation states and expression profiles. Overall, we highlight the power of IMC to provide quantitative insights into the spatial biology of the TIME. For Research Use Only. Not for use in diagnostic procedures.

Waveform design of radar coincidence imaging radiation field based on image entropy

AbstractRadar coincidence imaging (RCI) is a high‐resolution radar imaging mode which constructs a temporal spatial stochastic radiation field (TSSRF) and uses the correlation between reference signal and echoes for imaging. The correlation between the reference matrix and the echoes is the main factor affecting the imaging performance. In fact, radar target characteristics cause fluctuations in the radar cross section and variations in the scattering intensity of each resolution element. The latter degrades the correlation between the reference matrix and the echoes, seriously affecting the image reconstruction. This paper designs the waveform based on image entropy under fixed transmitting and receiving arrays. The targets with fluctuating scattering intensity at each resolution element are statistically modelled. Simulation results show this approach can improve the imaging performance and reduce the energy dissipation degree of the target grid.

Effects of 32 d of spaceflight on tendon collagen fibril morphology and nanomechanics

INTRODUCTION: Collagen is an essential component of connective tissue and plays a crucial role in elasticity, stability, and force distribution. While the adaptations of tendon to internal stimuli have been extensively researched, the impact of environmental factors (such as microgravity) on its structure and function at the nanoscopic scale (i.e., fibril level) remains largely unexplored. The purpose of this study was to determine the effects of 32 days (d) aboard the International Space Station (ISS) on murine tendon collagen fibril morphology and nanomechanics (Young’s Modulus, YM). We hypothesized there would be a decrease in fibril size and YM after spaceflight. Methods: Quadriceps tendon samples from female C57BL/6J mice from NASA Rodent Research-1 underwent chemical processing and mechanical isolation. Subsequently, collagen fibrils (n=56) were studied via atomic force microscopy (AFM; JPK NanoWizard 4a) to compare the morphology (diameter, height) and nanomechanics (average YM) between spaceflight (SF) and ground control (GC) specimens. The qp-BioAC-CB1 cantilever (spring constant: 0.3 N/m, tip radius: 10μm) was used under quantitative imaging mode (QI) for all force and morphological measurements. The data from 56 micrographs (SF n=30; GC n=26) was processed via the JPK Data Processing Software (Version 6.4.5.), and finally analyzed with Gwyddion (Version 2.62). A 2-way MANOVA compared all measurements. Results: More ‘small fibrils’ (height <50nm) were identified in the SF vs GC samples. SF fibrils averaged 20.3% smaller (width) compared to GC, but this difference was not significant (p>0.05). Additionally, while there was a trend for a lower YM in the SF samples, YM for SF specimens was not statistically different between groups (GC=3.26±1.94 MPa; SF= 2.76±1.44 MPa) (p>0.05). CONCLUSION: To our knowledge, this is the first investigation to use AFM QI-mode on tendon collagen fibrils after spaceflight. While there were no statistically significant changes in mean fibril size and YM between SF and GC, these results suggest that collagen fibrils may require more time to adapt to changes in their environment, and/or more rapid changes may take place at different levels of the collagen hierarchy. Our data provides valuable insight into mammalian tissue adaptations during spaceflight. Future research should continue these investigations with longer-duration missions to build a time-course of tendon adaptations to microgravity. FUNDING: CSUBIOTECH New Investigator Grant (JRB). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

A strong and ductile biocompatible Ti40Zr25Nb25Ta5Mo5 high entropy alloy

A non-equiatomic high entropy alloy (HEA) Ti40Nb25Zr25Ta5Mo5 (at.%) was designed by replacing 5% Ta with 5% Mo in a precursor Ti40Nb25Zr25Ta10 HEA for improved mechanical properties and reduced density. The Ti40Nb25Zr25Ta5Mo5 HEA fabricated by copper mould casting exhibited a nearly equiaxed grain structure (grain size: 96 ± 16 μm), but within each equiaxed grain, dendritic structures are discernible in the backscattered electron imaging mode. These dendrites are enriched in Ta, Nb and Mo, while the inter-dendritic regions contain higher Zr and Ti. The as-cast HEA achieved tensile yield strength (σ0.2) of 976 ± 8 MPa and strain to fracture (εf) of 16.80 ± 1.86%, well above the minimum requirements of σ0.2 and εf for medical-grade titanium alloy Ti–6Al–4V (759 MPa and 10%). The formation of microscale and nanoscale shear bands and the presence of significant dislocations in the shear band boundary region played a key role in allowing this as-cast HEA to achieve the excellent combination of tensile strength and ductility. Furthermore, the HEA exhibited a lower wear rate, lower coefficient of friction and much higher corrosion resistance in Hank's solution (electrochemical assessments) than Ti–6Al–4V, making it a promising alternative biomedical alloy.