Wide Field Research Articles

Custom microfluidic chip design enables cost-effective three-dimensional spatiotemporal transcriptomics with a wide field of view.

Spatial transcriptomic techniques offer unprecedented insights into the molecular organization of complex tissues. However, integrating cost-effectiveness, high throughput, a wide field of view and compatibility with three-dimensional (3D) volumes has been challenging. Here we introduce microfluidics-assisted grid chips for spatial transcriptome sequencing (MAGIC-seq), a new method that combines carbodiimide chemistry, spatial combinatorial indexing and innovative microfluidics design. This technique allows sensitive and reproducible profiling of diverse tissue types, achieving an eightfold increase in throughput, minimal cost and reduced batch effects. MAGIC-seq breaks conventional microfluidics limits by enhancing barcoding efficiency and enables analysis of whole postnatal mouse sections, providing comprehensive cellular structure elucidation at near single-cell resolution, uncovering transcriptional variations and dynamic trajectories of mouse organogenesis. Our 3D transcriptomic atlas of the developing mouse brain, consisting of 93 sections, reveals the molecular and cellular landscape, serving as a valuable resource for neuroscience and developmental biology. Overall, MAGIC-seq is a high-throughput, cost-effective, large field of view and versatile method for spatial transcriptomic studies.

Rapid automatic multiple moving objects detection method based on feature extraction from images with non-sidereal tracking

ABSTRACT Optically observing and monitoring moving objects, both natural and artificial, is important to human space security. Non-sidereal tracking can improve the system’s limiting magnitude for moving objects, which benefits the surveillance. However, images with non-sidereal tracking include complex background, as well as objects with different brightness and moving mode, posing a significant challenge for accurate multi-object detection in such images, especially in wide field-of-view telescope images. To achieve a higher detection precision in a higher speed, we proposed a novel object detection method, which combines the source feature extraction and the neural network. First, our method extracts object features from optical images such as centroid, shape, and flux. Then, it conducts a naive labelling based on those features to distinguish moving objects from stars. After balancing the labelled data, we employ it to train a neural network aimed at creating a classification model for point-like and streak-like objects. Ultimately, based on the neural network model’s classification outcomes, moving objects whose motion modes consistent with the tracked objects are detected via track association, while objects with different motion modes are detected using morphological statistics. The validation, based on the space objects images captured in target tracking mode with the 1-m telescope at Nanshan, Xinjiang Astronomical Observatory, demonstrates that our method achieves 94.72 per cent detection accuracy with merely 5.02 per cent false alarm rate, and a processing time of 0.66 s per frame. Consequently, our method can rapidly and accurately detect objects with different motion modes from wide-field images with non-sidereal tracking.

Temporal convolutional network with soft threshold and contractile self-attention mechanism for remaining useful life prediction of rolling bearings

Abstract RUL prediction is an effective approach to prevent system failures and cut maintenance expenditures. Due to the wide receptive field and the avoidance of future information leakage, temporal convolutional neural network (TCN) is widely applied for RUL estimation of bearings. However, the predictive performance of TCN is limited by the loss of degradation features and the breakdown of continuity of timing information. To overcome the above defects, hybrid temporal convolutional neural network with soft threshold and contractile self-attention mechanism (HTCN-SC) is presented. Firstly, the adaptive threshold is determined by the contraction self-attention mechanism with higher interpretability, which captures the contribution of different features to the estimation of RUL. Then, the soft threshold is employed to activate the degraded features. On the one hand, the degeneracy features endowed by the dilated causal convolution with obvious negative values are fully preserved. On the other hand, the noise components that are given low weights are completely suppressed compared to the original TCN. Finally, parallel branch composed of one-dimensional convolutional networks are used to supplement the continuity of time series. Degradation signals from different working conditions and bearings are employed to verify the performance of the HTCN-SC. The results indicate that HTCN-SC with accurate RUL estimation and generalization ability is an effective tool for rolling bearing health monitoring.

Local-Peak Scale-Invariant Feature Transform for Fast and Random Image Stitching.

Image stitching aims to construct a wide field of view with high spatial resolution, which cannot be achieved in a single exposure. Typically, conventional image stitching techniques, other than deep learning, require complex computation and are thus computationally expensive, especially for stitching large raw images. In this study, inspired by the multiscale feature of fluid turbulence, we developed a fast feature point detection algorithm named local-peak scale-invariant feature transform (LP-SIFT), based on the multiscale local peaks and scale-invariant feature transform method. By combining LP-SIFT and RANSAC in image stitching, the stitching speed can be improved by orders compared with the original SIFT method. Benefiting from the adjustable size of the interrogation window, the LP-SIFT algorithm demonstrates comparable or even less stitching time than the other commonly used algorithms, while achieving comparable or even better stitching results. Nine large images (over 2600 × 1600 pixels), arranged randomly without prior knowledge, can be stitched within 158.94 s. The algorithm is highly practical for applications requiring a wide field of view in diverse application scenes, e.g., terrain mapping, biological analysis, and even criminal investigation.

Real-time detection and discrimination of radioactive gas mixtures using nanoporous inorganic scintillators

The nuclear industry’s expansion to encompass carbon-free electricity generation from small modular reactors and nuclear fuel reprocessing necessitates enhanced detection and monitoring of pure beta-emitting radioactive elements such as 3H and 85Kr; this endeavour is crucial for nuclear safety authorities tasked with environmental monitoring. However, the short range of electrons emitted by these gases makes detection challenging. Current methods, such as ionization chambers and liquid scintillation, do not offer at the same time good sensitivity, real-time analysis and ease of implementation. We demonstrate an approach using a gas–solid mixture to overcome these limitations. We synthetized a transparent and scintillating nanoporous material, an aerogel of Y3Al5O12:Ce4+, and achieved real-time detection with an efficiency of 96% for 85Kr and 18% for 3H. The method reaches a sensitivity below 100 mBq per cm3 over 100 s measurement time. We are able to measure simultaneously as mixtures containing both 3H and 85Kr a capability not possible previously. Our results demonstrate a compact and robust detection system for inline measurement of strategic radioactive gases. This combination of concept and method enhances nuclear power plant management and contributes to environmental safeguarding. Beyond the detection issues, this concept opens a wide field of new methods for radionuclide metrology.

The Role of Widefield Optical Coherence Tomography Angiography in Assessing the Severity of Diabetic Retinopathy.

Physicians need an accurate understanding of diabetic retinopathy (DR) severity to optimally manage patients. The aim of this prospective study is to correlate the severity of macular and peripheral retinal vascular abnormalities seen on widefield (WF) optical coherence tomography angiography (OCTA) with DR grading based on WF fundus photography. The study included 150 eyes from 82 patients with treatment-naïve DR. All patients were imaged with WF fundus photography and swept-source WF OCTA. Quantitative and qualitative analyses of the foveal avascular zone (FAZ) size and shape, and measurement of capillary nonperfusion (CNP) areas, were performed from the OCTA images. The mixed-effects model was used to compare the DR grading from WF photography with the vascular changes seen on WF-OCTA, and Bonferroni correction was applied to the gradings. The mean [± standard deviation (SD)] age of patients was 55.5 (± 9.4) years. The WF-OCTA showed that an increasing size of the FAZ (from 0.442 (± 0.059) µm to 0.933 (± 0.086) µm) correlated with increasing severity of the DR (as determined with WF photography). The deep capillary plexus, FAZ size, and CNP areas in eyes with proliferative diabetic retinopathy (PDR) differed from those with mild nonproliferative diabetic retinopathy (NPDR) (p < 0.001). Most eyes with severe nonproliferative DR were found to have CNP in four quadrants [superficial capillary plexus (SCP) 60%, deep capillary plexus (DCP) 50%]. The WF-OCTA detected subtle neovascularization of the disc (NVD) in 7 eyes (10%) and neovascularization elsewhere (NVE) in 13 eyes (18%) that had been diagnosed with only moderate NPDR on WF photography. FAZ and CNP areas as measured by WF-OCTA correlate with DR severity. WF-OCTA can also detect subtle NVE and NVD that cannot be seen with fundus photography.

Mid-Infrared Photoacoustic Stimulation of Neurons through Vibrational Excitation in Polydimethylsiloxane.

Photoacoustic (PA) emitters are emerging ultrasound sources offering high spatial resolution and ease of miniaturization. Thus far, PA emitters rely on electronic transitions of absorbers embedded in an expansion matrix such as polydimethylsiloxane (PDMS). Here, it is shown that mid-infrared vibrational excitation of C─H bonds in a transparent PDMS film can lead to efficient mid-infrared photoacoustic conversion (MIPA). MIPA shows 37.5 times more efficient than the commonly used PA emitters based on carbon nanotubes embedded in PDMS. Successful neural stimulation through MIPA both in a wide field with a size up to a 100µm radius and in single-cell precision is achieved. Owing to the low heat conductivity of PDMS, less than a 0.5°C temperature increase is found on the surface of a PDMS film during successful neural stimulation, suggesting a non-thermal mechanism. MIPA emitters allow repetitive wide-field neural stimulation, opening up opportunities for high-throughput screening of mechano-sensitive ion channels and regulators.

Neck Clipping via Subtemporal Approach

The subtemporal approach offers the advantages of a wide surgical field in the anteroposterior direction and easy access to the proximal basilar artery. This approach can be adapted to treat low-positioned aneurysms using a tentorial incision, known as the subtemporal transtentorial approach. However, a disadvantage of the subtemporal approach is the risk of injury to the temporal lobe. To mitigate this risk, it is important to ensure proper positioning, adequate cerebrospinal fluid drainage, preservation of the bridging veins, and intermittent retraction of the temporal lobe.

Endoscopic Approaches in Skull Base Surgery

Endoscopy offers access to a clear, wide surgical field in deep-brain areas. In recent years, opportunities for the use of endoscopy in endonasal or small keyhole approaches have been increasing. However, ascertaining the tumor-specific suitability of endoscopic surgery remains unclear. In this article, we introduce the general concept of endoscopic surgery for skull base tumors. The optimal goal for all types of skull base surgeries is maximum tumor removal with preservation of function. Therefore, it is important to understand the benefits and limitations of various endoscopic approaches for the skull base.

Modified colored three-dimensional posterior and temporal cranial fossa model with mobility of the joint between C1 and occipital condyle

BackgroundSkull base surgery requires anatomical knowledge and appropriate surgical technique in bone drilling. We developed a newly modified three-dimensional (3D) model of the posterior cranial fossa as a learning tool that improves knowledge of skull base anatomy and surgical approaches, including skull base drilling techniques. MethodsThis bone model of the posterior cranial fossa was created based on computed tomography data using a 3D printer, and incorporates artificial cranial nerves, cerebral vessels, bony structures, dura mater, and cerebellar tentorial dura. These anatomical components are differentiated with various colors. In addition, the atlanto-occipital junction can be mobilized to fully expose the surface of the cartilage between the C1 condyle and occipital condyle to allow drilling to open the hypoglossal canal under a wide surgical field. The usefulness of the model for practicing skull base surgical approaches was evaluated. ResultsExperience of bone drilling, dural dissection, and 3D positioning of important structures, including cranial nerves and blood vessels, was identical to that in actual surgery. ConclusionsThis model is designed to facilitate teaching anatomical knowledge and essential epidural procedure-related skills, and is useful for teaching the essential elements of posterior skull base surgery.

Evaluation of the Effectiveness of Cervical One-Hole Split Endoscopic Keyhole Surgery for Cervical Radiculopathy.

One-hole Split Endoscopy (OSE) is a newer surgical modality that can be applied to posterior cervical foraminotomy (PCF), lumbar discectomy, laminectomy, and decompression. It incorporates intervertebral foraminotomy, open surgery, and other lumboendoscopic techniques with a wide observation field, free space, and compatibility with various spinal surgical techniques and instruments. This study investigated the clinical efficacy of minimally invasive posterior cervical nucleus pulposus removal for cervical spondylotic radiculopathy (CSR) by OSE-Keyhole technique. This was a retrospective study of 63 patients treated with OSE keyhole treatment for CSR between May 2021 and September 2023 at Qilu Hospital of Shandong University, Qilu Hospital of Shandong University (Qingdao, China), and Second Hospital of Shandong University, respectively. Clinical outcomes included patients' preoperative and postoperative visual analogue scale (VAS) - arm and neck, Japanese Orthopaedic Association Assessment Treatment Score (JOA) - cervical spine, which were collected at baseline, two days postoperatively, one month postoperatively, and three months postoperatively after the last follow-up visit for evaluation, and perioperative indicators, including intraoperative bleeding, length of hospital stay, postoperative complications, and reoperations, which were also collected. Statistical analyses were performed for the baseline data and follow-up results of 63 patients. Compared to the preoperative baseline values, the follow-up results two days, one month and three months after surgery showed significant improvements in vas-arm, neck and JOA scores in the operated patients (P<0.05) as well as a reduction in all perioperative-related indices. In the treatment of cervical pain and disability due to radiculopathy, OSE keyhole removal of the posterior cervical nucleus pulposus is a better clinical option as it is less invasive and recovers better postoperatively.

Design of a diamond-based in-vessel soft x-ray detector for the SPARC tokamak.

The in-vessel silicon diode arrays that are used for soft x-ray detection in many tokamaks are sensitive to neutron damage, making them unsuitable for burning plasma devices such as SPARC. In such a device, the silicon diodes would need to be placed far from the plasma-limiting their field of view-or an alternative detector could be used. Here, we present the design of a camera containing an array of chemical vapor deposition single-crystal diamonds, which will be placed in the upper and lower port plugs of the SPARC tokamak with a large enough view of the poloidal cross section to enable tomographic inversion. The camera design presented here is optimized to provide a wide field of view of the poloidal cross section. Simulated plasma conditions are used to estimate the x-ray signal that this detector array will receive and to fine-tune the camera placement within the tokamak.

Hemispherical Retina Emulated by Plasmonic Optoelectronic Memristors with All-Optical Modulation for Neuromorphic Stereo Vision.

Binocular stereo vision relies on imaging disparity between two hemispherical retinas, which is essential to acquire image information in three dimensional environment. Therefore, retinomorphic electronics with structural and functional similarities to biological eyes are always highly desired to develop stereo vision perception system. In this work, a hemispherical optoelectronic memristor array based on Ag-TiO2 nanoclusters/sodium alginate film is developed to realize binocular stereo vision. All-optical modulation induced by plasmonic thermal effect and optical excitation in Ag-TiO2 nanoclusters is exploited to realize in-pixel image sensing and storage. Wide field of view (FOV) and spatial angle detection are experimentally demonstrated owing to the device arrangement and incident-angle-dependent characteristics in hemispherical geometry. Furthermore, depth perception and motion detection based on binocular disparity have been realized by constructing two retinomorphic memristive arrays. The results demonstrated in this work provide a promising strategy to develop all-optically controlled memristor and promote the future development of binocular vision system with in-sensor architecture.

Small Magellanic Cloud Cepheids Observed with the Hubble Space Telescope Provide a New Anchor for the SH0ES Distance Ladder

We present phase-corrected photometric measurements of 88 Cepheid variables in the core of the Small Magellanic Cloud (SMC), the first sample obtained with the Hubble Space Telescope's (HST) Wide Field Camera 3, in the same homogeneous photometric system as past measurements of all Cepheids on the SH0ES distance ladder. We limit the sample to the inner core and model the geometry to reduce errors in prior studies due to the nontrivial depth of this cloud. Without crowding present in ground-based studies, we obtain an unprecedentedly low dispersion of 0.102 mag for a period–luminosity (P–L) relation in the SMC, approaching the width of the Cepheid instability strip. The new geometric distance to 15 late-type detached eclipsing binaries in the SMC offers a rare opportunity to improve the foundation of the distance ladder, increasing the number of calibrating galaxies from three to four. With the SMC as the only anchor, we find H 0 = 74.1 ± 2.1 km s−1 Mpc−1. Combining these four geometric distances with our HST photometry of SMC Cepheids, we obtain H 0 = 73.17 ± 0.86 km s−1 Mpc−1. By including the SMC in the distance ladder, we also double the range where the metallicity ([Fe/H]) dependence of the Cepheid P–L relation can be calibrated, and we find γ = −0.234 ± 0.052 mag dex−1. Our local measurement of H 0 based on Cepheids and Type Ia supernovae shows a 5.8σ tension with the value inferred from the cosmic microwave background assuming a Lambda cold dark matter (ΛCDM) cosmology, reinforcing the possibility of physics beyond ΛCDM.

Strategic Attention Guidance: The Impact of Dual and Single Cues in Wide Field of View Searches

Strategic Attention Guidance: The Impact of Dual and Single Cues in Wide Field of View Searches

Association of microaneurysms with retinal vascular alterations in patients with retinal vein occlusion

ObjectiveTo investigate the localization, distribution, and type of central microaneurysms (MAs) and their relationship with retinal vascular alterations in patients with retinal vein occlusion (RVO). MethodsIn this cross-sectional study, ultra-widefield color fundus photography (UWF-CF), standard and single-capture 65° widefield (WF) optical coherence tomography angiography (OCTA) were performed in consecutive patients with RVO treated at the Department of Ophthalmology and Optometry, Medical University of Vienna. UWF-CF, en face and B-Scans in 6 mm × 6 mm OCTA were examined for detection of MAs. Nonperfusion areas (NPA) and collateral vessels (CV) were evaluated on WF-OCTA, ghost vessels (GV), and tortuous vessels (TV) on UWF-CF. ResultsOne-hundred-and-twelve patients were included in the study, and data from 59 eyes of 59 patients with disease duration longer than 3 months, good image quality, and without relevant ocular comorbidities were eligible for statistical analysis. Fifty-six of 59 (94.9%) patients were previously treated with anti-vascular endothelial growth factor agents for macular edema, 31 of 59 (52.5%) patients presented with MAs in the central 6 mm and 60 MAs were found in total using multimodal imaging. There was no statistically significant difference in the greatest diameter of fluid-associated versus non-fluid-associated MAs (p = 0.53). Eyes with MAs were associated with CV, TV, and GV (χ2-test; p < 0.001, p = 0.0498, and p = 0.001). Median NPA was 27.3 mm2 (quartiles 1.3–62.8 mm2) in eyes with MAs and 0 mm2 (quartiles 0–36.2 mm2) in eyes without MAs (Mann-Whitney-U-test; p = 0.018). ConclusionMAs were associated with extensive NPA, the presence of CV, GV, and TV. There was no correlation between the diameter of the MA and the adjacent intraretinal fluid in our predominantly pretreated RVO study patients.

How to Better Qualify ICT Graduates to Support Digital Education: A contribution from CALOHEE Tuning project qualifications framework

The Information and Communications Technology subject area is a broad multidisciplinary field of academic research and professional practice covering many topics ranging from electronics to system and network administration, to software development, cyber security, VR, AR, IoT and AI. Due to its nature, it cooperates closely with diverse areas, most notably eLearning and digital education. As contemporary educational institutions undergo a digital transformation, by which its processes are reengineered to take most of the possibilities offered by the emerging technologies, the contribution of the ICT field has become transversal and consequently of critical importance. The term ICT which refers to this wide multidisciplinary field differentiates from IT, which applies specifically to the management and use of computer systems to store, retrieve, transmit, and manipulate data. The continuous expansion of the field to new territories of practice such as education is requiring additional knowledge, skills and wider competences acquisition. In addition, high volatility of the job market creates the need for very adaptable professional profiles. As a result, there is a pressure from the job market for shorter and more job-oriented programmes, but also for competence frameworks which may serve as references for quality higher education and training. In this paper we present the Tuning Quality Reference Framework (QRF) for ICT which was developed as part of the CALOHEE Erasmus+ funded project. A multidisciplinary team with experts from 12 different countries (Portugal, Lithuania, Germany, Italy, Spain, Austria, Belgium, Greece, Turkey, Finland, Ireland and Romania) took part in the task. The QRF is built in a way to flexibly address all the mentioned complexity and continuously emerging new requirements including educational institutions and non-formal education organisations. The approach used also supports innovation in learning, teaching and assessment practices in ICT degrees, fostering open and digital education.

Dissecting the planetary nebula NGC 4361 with MUSE

Optical integral field spectroscopy of planetary nebulae (PNe) offers a unique tool to explore the spatial relationships between the complex mixture of the many components (neutral, low- and high-ionisation gas, dust, and the central star) and their underlying physical conditions. The optical line and continuum emission in the very-high-ionisation Galactic PN, NGC 4361, were mapped to study the distribution of ionisation, extinction, electron temperature, and density. Based on commissioning data, MUSE Wide Field (60times 60$''$) normal-mode (4750-9300\ observations of NGC 4361 were reduced. The PN is larger than a single MUSE field and only the central 1 arcmin2 of the PN was observed in good conditions. Emission images in recombination and collisionally excited lines were extracted and the line ratios provided the dust extinction, electron density and temperature, and ionic abundances using standard techniques. A family of compact low-ionisation knots (dubbed 'freckles') was discovered and techniques developed to measure their spectra, independently of the extended high-ionisation medium. The nebula is confirmed as optically thin in the H-ionising continuum, based on its very low He i emission, even to the edges of the field. The electron temperature, $T_ e $, is shown to have a large-scale spatially coherent structure, as indicated by a previous long-slit spectrum. Prior to this study, no low-ionisation emission had been positively detected, although MUSE revealed both weak extended N ii and O ii and $&gt;$100 spatially unresolved knots. There are several linear associations of these knots, but none of them point convincingly back to the central star. They have low-to-moderate ionisation with $T_ e $ sim 11000\,K e $ sim 1500 cm$^ $ and generally exhibit a higher extinction than the extended high-ionisation nebula. Within the MUSE field, a low-redshift emission-line galaxy was serendipitously found to be hiding behind NGC 4361. The spectrum of this dwarf galaxy was carefully extracted from the bright foreground nebular emission and the galaxy's line and continuum properties were then determined. NGC 4361 is not completely optically thin, as indicated by several extended regions and many compact features of lower ionisation emission. The low-ionisation 'freckles' identified here do not clearly appear to differ in (He, N, O, S) abundance with respect to the extended high-ionisation gas. The spatial distribution and radial velocities of these features suggest that they belong to a thick disk oriented perpendicular to the large-scale nebular gas, which may perhaps be remnants of an earlier structure. The low-luminosity disk galaxy at sim 87\,Mpc has bright H ii regions with metallicity 12+log(O/H) cong 8.4 and is suggested to be a Magellanic irregular or low-mass spiral.

An advanced hybrid deep learning model for accurate energy load prediction in smart building

In smart cities, sustainable development depends on energy load prediction since it directs utilities in effectively planning, distributing and generating energy. This work presents a novel hybrid deep learning model including components of the Improved-convolutional neural network (CNN), bidirectional long short-term memory (Bi-LSTM), Graph neural network (GNN), Transformer and Fusion Layer architectures for precise energy load forecasting. Better feature extraction results from the Improved-CNN's dilated convolution and residual block accommodation of wide receptive fields reduced the vanishing gradient problem. By capturing temporal links in both directions, Bi-LSTM networks help to better grasp complicated energy use patterns. Graph neural networks improve predictive capacities across linked systems by characterizing the spatial relationships between energy-consuming units in smart cities. Emphasizing critical trends to guarantee reliable forecasts, transformer models use attention methods to manage long-term dependencies in energy consumption data. Combining CNN, Bi-LSTM, Transformer and GNN component predictions in a Fusion Layer synthesizes numerous data representations to increase accuracy. With Root Mean Square Error of 5.7532 Wh, Mean Absolute Percentage Error of 3.5001%, Mean Absolute Error of 6.7532 Wh and R2 of 0.9701, the hybrid model fared better than other models on the ‘Electric Power Consumption’ Kaggle dataset. This work develops a realistic model that helps informed decision-making and enhances energy efficiency techniques, promoting energy load forecasting in smart cities.

Going beyond hardware limitations with advanced stray light calibration for the Metop-3MI space instrument

Space optical instruments play a pivotal role in enhancing our understanding of the universe and our planet, and are crucial in addressing the urgent challenges posed by climate change. In this context, stray light has emerged as a primary performance limitation. Originating from ghost reflections or scattering, it obscures essential details and introduces false information into images. With the demand for increasingly high-performing instruments, mitigation through hardware optimization is becoming insufficient. We are entering an era where future instruments require a stray light correction algorithm to meet user specifications, necessitating extensive on-ground calibration. This paper examines the Metop-3MI Earth observation instrument, which, with wide field of view, broad spectral range, and multi-polarization capabilities, epitomizes the challenges of stray light calibration and correction. A custom calibration apparatus was constructed to evaluate the complex stray light dependence on field-of-view, wavelength, and polarization. Data were processed, and stray light kernels database was derived, which then fed into a specially developed correction algorithm. Applied to the image of an extended scene, it effectively reduces stray light by a remarkable factor of 91. This achievement sets a new standard for low-stray-light instruments and provides a comprehensive case study for future missions.