Dual-mode photoacoustic/ultrasound endoscopy (ePAUS) is a promising tool for preclinical and clinical interventions. To be clinically useful, ePAUS must deliver high-performance ultrasound imaging comparable to commercial systems and maintain high photoacoustic imaging performance at long working distances. This requires a transducer with an intact physical aperture and coaxial alignment of acoustic and optical beams within the probe, a challenging integration task. We present a high-performance ePAUS probe with a miniaturized, optically transparent ultrasonic transducer (TUT) called ePAUS-TUT. The 1.8-mm-diameter probe, fitting into standard endoscopic channels, aligns acoustic and optical beams efficiently, achieving commercial-level ultrasound and high-resolution photoacoustic imaging over long distances. These imaging capabilities were validated through in vivo imaging of a rat’s rectum and a pig’s esophagus. The ePAUS-TUT system substantially enhances feasibility and potential for clinical applications.

Photoacoustic microscopy (PAM) has been widely used in biomedical studies to provide high-resolution 3D anatomical, functional, and molecular images of living subjects. While handheld PAM systems have been proposed to extend its applicability, it has proved challenging to achieve a compact device that combines fast imaging with high spatial resolution and signal to noise ratio. Here we demonstrate a handheld PAM probe integrating a fiber scanner and high-frequency transparent ultrasound transducer (TUT), called hPAM-TUT. The compact system (measuring 17 mm in diameter, with a 90 mm long rigid body) achieves high lateral and axial resolutions (7 and 47 μm, respectively), has a 2.6 mm diameter field of view, and delivers a single volumetric image in 1.5 s. In living rats, we used hPAM-TUT to visualize various abdominal organs, and in mice we used it to observe epinephrine-induced vascular changes and image the anatomy and functioning of lymphatic vessels after injection of Evans blue dye. Additionally, we successfully delineated murine vascular networks in early metastatic tumors. This handheld PAM probe shows promise for both clinical and research applications in such fields as dermatology, oncology, and intraoperative imaging.

The PLS-II is a third-generation light source; it has been operating since 2011. It has a double-bend structure with non-zero dispersion along the straight section. Here, we assess three proposed upgrades to the PLS-II. First, we evaluate use of a canted insertion device beamline to increase the number of beamlines. Second, we evaluate the consequences of upgrading the bending magnet to a superbend magnet; the change doubles the strength of the bending field and increases the critical energy from 8.7 keV to 17 keV. Finally, a short-bunch mode for time-resolved experiments is studied; the goal is to achieve a bunch length of 5 ps rms by using a low-alpha mode and increasing the RF gap voltage.

Background/Objectives: While human epidermal growth factor receptor 2 (HER2) immunohistochemistry (IHC) is pivotal for breast cancer management, its reliance on additional tissue processing beyond routine H&E staining remains a clinical burden. Although virtual staining offers a potential solution, current methods often fail to explicitly account for HER2 score-specific expression patterns. To address this gap, we developed a score-aware framework designed for the precise generation of virtual HER2 IHC images. Methods: We introduce the non-contrastive multi-task (NCMT) framework, which integrates negative-free patch alignment, style–content constraints, and auxiliary HER2 score supervision for high-fidelity H&E-to-IHC translation. For rigorous evaluation, the model was validated on the BCI dataset, utilizing an official split of 3896 training and 977 independent test images derived from 51 whole-slide images. Results: NCMT demonstrated superior virtual staining performance, achieving a Fréchet Inception Distance (FID) of 38.8, a Kernel Inception Distance (KID) of 5.6, and an average Perceptual Hash Value (PHV) of 0.439. In downstream HER2 scoring tasks, while virtual IHC images alone yielded an accuracy of 83.01%, the fusion of H&E and virtual IHC further elevated performance to 97.85% accuracy and a 98.23% F1 score. These findings suggest that our framework effectively preserves diagnostic features while providing complementary information to H&E-based morphological analysis. Conclusions: NCMT enables HER2 score-aware virtual IHC generation from H&E and can serve as a complementary tool for HER2 assessment in digital pathology.

There is an increasing demand for ultrasound imaging technologies, particularly wearable and portable systems, for continuous physiological monitoring applications. Although some recent flexible ultrasound devices have adopted polymer encapsulations, typical rigid transducer designs still include metal housings and costly electrodes, contributing to increased device weight and fabrication cost. To address these limitations, we developed an aluminum-electrode/3D-printed polymer-housing ultrasound transducer (APUT) utilizing a polyvinylidene fluoride piezoelectric film. Compared to a gold-electrode/metal-housing ultrasound transducer, the APUT material costs and total weight were approximately 66% and 86% lower, respectively. Acoustic evaluation revealed a center frequency of 24.5 MHz and a fractional bandwidth of 60.9%, with axial and lateral resolutions of 51 and 152 μm, respectively. Furthermore, during a 3-h pulsed operation test, the APUT exhibited an initial increase in capacitance followed by a relatively stable response, with no progressive surface-temperature increase detected within the accuracy of the measurement method. Finally, successful ex vivo imaging of chicken breast tissue confirms the APUT’s biomedical applicability, highlighting its potential as a wearable, portable, and disposable ultrasound platform.