Axial Dimensions Research Articles

Classifying 2-generated symmetric axial algebras of Monster type

In [15], Yabe gives an almost complete classification of primitive symmetric 2-generated axial algebras of Monster type, leaving open the case of algebras in characteristic 5 and axial dimension larger than 5. In this note, we complete the classification of these algebras, by constructing a new infinite-dimensional primitive 2-generated symmetric axial algebra Hˆ of Monster type (2,12) over a field of characteristic 5, and showing all the cases not falling into Yabe's classification are factors of Hˆ.

Characterization of the Ultrasound Localization Microscopy Resolution Limit in the Presence of Image Degradation.

Ultrasound localization microscopy (ULM) has been able to overcome the diffraction limit of ultrasound imaging. The resolution limit of ULM has been previously modeled using the Cramér-Rao lower bound (CRLB). While this model has been validated in a homogeneous medium, it estimates a resolution limit, which has not yet been achieved in vivo. In this work, we investigated the effects of three sources of image degradation on the resolution limit of ULM. The Fullwave simulation tool was used to simulate acquisitions of transabdominal contrast-enhanced data at depth. The effects of reverberation clutter, trailing clutter, and phase aberration were studied. The resolution limit, in the presence of reverberation clutter alone, was empirically measured to be up to 39 times worse in the axial dimension and up to 2.1 times worse in the lateral dimension than the limit predicted by the CRLB. While reverberation clutter had an isotropic impact on the resolution, trailing clutter had a constant impact on both dimensions across all signal-to-trailing-clutter ratios (STCR). Phase aberration had a significant impact on the resolution limit over the studied analysis ranges. Phase aberration alone degraded the resolution limit up to 70 and 160 [Formula: see text] in the lateral and axial dimensions, respectively. These results illustrate the importance of phase aberration correction and clutter filtering in ULM postprocessing. The analysis results were demonstrated through the simulation of the ULM process applied to a cross-tube model that was degraded by each of the three aforementioned sources of degradation.

Praktični model za procenu zapremine Taro Kokoyam na osnovu njegovih aksijalnih dimenzija

Taro Cocoyam is prone to attack by rodents, insect pests and environmental elements. After drying, it is stored to evade wastage. In an effort to efficiently develop storage system, fundamental physical parameter such as volume of the fresh cocoyam with respect to its axial dimensions should be well expressed and modelled for easy estimation. In this study, fresh Taro Cocoyam samples were sourced, cleaned and packaged. Ten unpeeled samples were used in determining initial moisture content (% w.b). The axial dimensions of fifty unpeeled samples were measured and used to compute arithmetic mean diameter (DA). Corresponding true volume (VT) was found using water displacement approach. The bulk samples were grouped based on DA, into seven (7) size ranges. Mean and standard deviation of each parameter were computed. The model was established, verified and validated. Statistical analysis showed that the value of coefficient of determination (R2 ) was almost equals correlation coefficient (r ≈ 1). The values of reduced Chi-square (chc 2 ), root mean square error (RMSE) and mean bias error (MBE) were not that high. The values of coefficient of residual mass (CRM) and modelling efficiency (EF) were almost perfect. Therefore, the model established is practically good for estimating volume of Taro Cocoyam which could find application in the design of feed hopper and storage system.

Key technologies of 18 MeV self-extraction cyclotron

In this work, an 18 MeV self extraction high current cyclotron is designed, which provides a feasible design scheme for the self extraction system. For the main magnet, it is designed by restricting the parameter change of the main magnetic field through “three judgments”. For the self extraction system, the phase space suitable for particle extraction is scanned by injecting the phase space, and the gradient correction magnet is used to increase the acceptance of the extracted beam. For the harmonic coil, through the second harmonic change of the magnetic field, the beam characteristics are analyzed and the position of the harmonic coil is determined. Under the condition of scanning different harmonic coil surface currents, the extraction of the beam is obtained, and then the phase space of the beam is pushed to the acceptance. In order to match the radial dimension and the axial dimension of the target beam and obtain a stronger beam, the magnetic channel of the double structure is selected and the related design idea is given. The final beam size is 30.5 mm × 12.9 mm, the particles that can be extracted account for 82.62% of the successfully accelerated particles.

Molecular Segmentation of the Spinal Trigeminal Nucleus in the Adult Mouse Brain.

The trigeminal column is a hindbrain structure formed by second order sensory neurons that receive afferences from trigeminal primary (ganglionic) nerve fibers. Classical studies subdivide it into the principal sensory trigeminal nucleus located next to the pontine nerve root, and the spinal trigeminal nucleus which in turn consists of oral, interpolar and caudal subnuclei. On the other hand, according to the prosomeric model, this column would be subdivided into segmental units derived from respective rhombomeres. Experimental studies have mapped the principal sensory trigeminal nucleus to pontine rhombomeres (r) r2-r3 in the mouse. The spinal trigeminal nucleus emerges as a plurisegmental formation covering several rhombomeres (r4 to r11 in mice) across pontine, retropontine and medullary hindbrain regions. In the present work we reexamined the issue of rhombomeric vs. classical subdivisions of this column. To this end, we analyzed its subdivisions in an AZIN2-lacZ transgenic mouse, known as a reference model for hindbrain topography, together with transgenic reporter lines for trigeminal fibers. We screened as well for genes differentially expressed along the axial dimension of this structure in the adult and juvenile mouse brain. This analysis yielded genes from multiple functional families that display transverse domains fitting the mentioned rhombomeric map. The spinal trigeminal nucleus thus represents a plurisegmental structure with a series of distinct neuromeric units having unique combinatorial molecular profiles.

THE DESIGN OF THE TOROIDAL PLANETARY TWO-ROW VARIATOR OF VEHICLES WITH INCREASED REQUIREMENTS FOR THE RANGE OF GEAR RATIOS AND SMOOTH RUNNING

The article presents the design of the toroidal planetary two-row variator, variants of designs of control units of this variators and a method for calculating planetary mechanisms with inclined axes of satellites. (Research purpose) The research purpose is in developing kinematic and schematic diagrams of a two-row planetary variator; formulating and propose the methodology for calculating gear ratios, angular velocities of satellites and geometric transmission parameters; proposing variants of the variator control unit for the purpose of adaptation or unification with agricultural machinery units. (Materials and methods) The research used data from domestic and foreign authors concerning the design and theoretical description of in-line and planetary friction variators, including toroidal. Authors conducted a patent study of design options for friction planetary variators, the gear ratio of which is changed by changing the position of the satellite axes. Kinematic schemes of the proposed design options were compiled in order to develop a method for calculating gear ratios. (Results and discussion) The article presents the design that can be used in transmissions of transport and traction machines operating in the agricultural sectors. It favorably compares with analogues in small axial and overall dimensions, less wear of friction surfaces and a large range of regulation. The range of such planetary variators, designed on the basis of a combination of increasing and decreasing rows, favorably compares with the range of friction variators with toroidal rolling bodies. The article also presents the methodology for calculating gear ratios that can be used for planetary mechanisms with satellite axes that are not parallel to the main axis of the mechanism. A parametric scheme allows you not only to obtain the values of the variator gear ratios for given geometric parameters, but also to calculate these parameters automatically at the required gear ratios. (Conclusions) The developed concept of a combination of series gear ratios can be applied in the designs of planetary variators and used as a basis in further scientific developments.

Modeling of Sediment Transport Using Wave Height action in Fialaka Marina

Failaka Island is the second-largest and one of the most important islands of Kuwait from the point of view of tourism located in the north Arabian Gulf. It has a marina constructed in 1979 and managed by the Ministry of Communication (MOC) and a tourism enterprise, and is widely used for its ferry landing facility. The coastal waters around Failaka are turbid and current velocities tend to be as high as ~0.5 m/s during spring tide. The marina basin, with axial plan view dimensions of about 285 m by 260 m experiences shoaling of naturally flocculated fine (cohesive) sediment and coarse sand in the entrance channel and more generally in the southern half of the basin. A particularly noteworthy zone of heavy and visible shoaling is along the inner side of the south breakwater close to the entrance. The marina at Failaka Island is suffering from siltation and sediment deposing issues. This study was carried out numerically to assess the annual sedimentation, sediment direction, and longshore current from locations around the existing marina to help in a suggestion of the solutions to reduce the siltation and sediment deposing based on sediments transport direction on marina entrance. A newly developed numerical solution for annual longshore sediments transport was used to estimate the total sediment transport and its direction. The study shows that the annual sediment transport directions which affect the Fialaka marina entrance are coming from the south to north due to wave action.

Design and simulation of a compact Ku-band RTTO with power divider extraction structure

The radial transit time oscillator (RTTO) has attracted much attention because of its high power capacity and pure mode of output microwave. To make the high power microwave (HPM) source devices more compact and to enable it to measure the output microwave mode quantitatively, this paper proposed a compact Ku-band RTTO with the power divider extraction structure (PDES). The radial decreasing magnetic field is applied to decreasing the mass of excitation system. Compared the conventional uniform solenoids, it can reduce the mass by about 30%. In the coaxial output waveguide, the PDES is used instead of the traditional support rods connecting the inner and outer conductors so as to convert TEM mode into TE10 mode efficiently. This structure can not only help shorten the axial dimension of the device, but also make it possible to measure the output microwave mode more accurately online. In particle-in-cell (PIC) simulation, the proposed Ku-band RTTO can output HPMs with the power of 3.05 GW and the frequency of 14.36 GHz, and the working efficiency is 40.3%. The maximum radial electric field intensity in the extraction cavity is 0.92 MV/cm, and the maximum electric field intensity in the PDES is 0.52 MV/cm, both of which are lower than the radio frequency (RF) breakdown threshold of metal materials.

Assessing the robustness of artificial intelligence powered planning tools in radiotherapy clinical settings-a phantom simulation approach.

Artificial intelligence (AI) based radiotherapy treatment planning tools have gained interest in automating the treatment planning process. It is essential to understand their overall robustness in various clinical scenarios. This is an existing gap between many AI based tools and their actual clinical deployment. This study works to fill the gap for AI based treatment planning by investigating a clinical robustness assessment (CRA) tool for the AI based planning methods using a phantom simulation approach. A cylindrical phantom was created in the treatment planning system (TPS) with the axial dimension of 30 cm by 18 cm. Key structures involved in pancreas stereotactic body radiation therapy (SBRT) including PTV25, PTV33, C-Loop, stomach, bowel and liver were created within the phantom. Several simulation scenarios were created to mimic multiple scenarios of anatomical changes, including displacement, expansion, rotation and combination of three. The goal of treatment planning was to deliver 25 Gy to PTV25 and 33 Gy to PTV33 in 5 fractions in simultaneous integral boost (SIB) manner while limiting luminal organ-at-risk (OAR) max dose to be under 29 Gy. A previously developed deep learning based AI treatment planning tool for pancreas SBRT was identified as the validation object. For each scenario, the anatomy information was fed into the AI tool and the final fluence map associated to the plan was generated, which was subsequently sent to TPS for leaf sequencing and dose calculation. The final auto plan's quality was analyzed against the treatment planning constraint. The final plans' quality was further analyzed to evaluate potential correlation with anatomical changes using the Manhattan plot. A total of 32 scenarios were simulated in this study. For all scenarios, the mean PTV25 V25Gy of the AI based auto plans was 96.7% while mean PTV33 V33Gy was 82.2%. Large variation (16.3%) in PTV33 V33Gy was observed due to anatomical variations, a.k.a. proximity of luminal structure to PTV33. Mean max dose was 28.55, 27.68 and 24.63 Gy for C-Loop, bowel and stomach, respectively. Using D0.03cc as max dose surrogate, the value was 28.03, 27.12 and 23.84 Gy for C-Loop, bowel and stomach, respectively. Max dose constraint of 29 Gy was achieved for 81.3% cases for C-Loop and stomach, and 78.1% for bowel. Using D0.03cc as max dose surrogate, the passing rate was 90.6% for C-Loop, and 81.3% for bowel and stomach. Manhattan plot revealed high correlation between the OAR over dose and the minimal distance between the PTV33 and OAR. The results showed promising robustness of the pancreas SBRT AI tool, providing important evidence of its readiness for clinical implementation. The established workflow could guide the process of assuring clinical readiness of future AI based treatment planning tools.

Genetic Variability of Tunisian Faba Beans (Vicia faba L.) Based on Seeds’ Morphophysical Properties as Assessed by Statistical Analysis

Faba bean (Vicia faba L.) is a legume crop cultivated for its nutritious seeds that are an important worldwide source of human food and feed. Seeds characterization is a prerequisite step for faba bean quality improvement. The morphophysical characterization of the seeds of twenty-four local faba bean accessions following the UPOV descriptors and the AOAC International standards was carried out and assessed with an approach based on Euclidean statistical model. “205 Bulk” was the unique accession harboring white hilum color seed which is linked to low convicine grain content. Irregular seed shape was the most observed character among the studied accessions except “Badii” displaying an elliptical seed shape; therefore, seed shape did not allow discrimination within our Tunisian germplasm. Interestingly, the physical characters of the seeds showed significant diversity between the accessions for all the measured parameters. A highly significant variability was observed for axial, length, and width dimensions of seeds, with “Memdouh” being the longest and largest seed accession, whereas “01-02” was the shortest and narrowest. Classification of the studied faba bean germplasm accessions based on morphophysical characters using clustering by Euclidean distance revealed three different groups. Moreover, multivariate PCA analysis further classified the faba bean accessions into four main clusters. Correlation study performed by using Spearman’s test established positive correlations within physical parameters of seeds such as between mean length and mean width of seeds. Therefore, using morphophysical parameters screening, valuable phenotypes have been selected for deeper physiological characterization and further breeding programs.

Dynamic behavior and damage assessment of RC columns subjected to lateral soft impact

In this study, the performance and damage behavior of reinforced concrete (RC) columns under lateral soft impact are comprehensively investigated using 3D finite element (FE) analysis. Firstly, refined FE models of RC columns are developed in LS-DYNA, and the corresponding simulation techniques are verified against existing experimental testing data. Then, response characteristics of a typical column under soft impact are examined, and a section damage factor is defined to quantify the damage evolution of impacted columns. After that, the effects of various design parameters, including impactor stiffness, impact elevation, axial force ratio, section dimension, and combination of impact mass and velocity, on the dynamic behavior of columns are examined. Finally, criteria for both flexural damage and shear damage are proposed based on the section damage factor, and the resistance dynamic increase factor (RDIF) of RC columns under soft impact is utilized to establish a rapid damage assessment methodology. From these results, it is proved that the dynamic responses and failure modes of RC columns under soft impact are quite different from those under hard impact. The impactor stiffness and impact elevation have a significant effect on the mechanical mechanism of columns, and the column resistance generally increases with the axial force to a certain extent. In addition, RDIF of columns decreases with the increase in the ratio of the impact time at peak force tp to the column natural period Tcol.

To calculate the axial dimensions of inkjet devices for hydraulic transport of sand and gravel materials

The article presents the results of the dredger in a deep deposit of sand and gravel materials. It was found that when the diameter of the suction pipe exceeds the diameter of the inlet mixing chamber by 150 mm, the actual pressure from the ejector does not exceed one meter, and with an increase in the supply of the suction pump as a result of a sharp jump in hydraulic resistance, the vacuum is disrupted. It was also found that the effect on the calculated compression ratio of the jet apparatus increases with an increase in the injection coefficient and the input velocity of the injected stream.

Research on vacuum properties of CuCrZr UHV flanges for the Hefei Advanced Light Facility

Hefei Advanced Light Facility (HALF), one of the Diffraction-Limited Storage Rings (DLSR), requires low-impedance flanges to be welded with Oxygen-free with Ag (OFS) vacuum chamber. In this paper, CuCrZr alloy as flange material and spring energized metal C-ring sealing structure are proposed. Two types of CuCrZr flanges have been designed, which are chain clamp and bolted flange, respectively. Chain clamp flanges are planed for compact areas, due to its small axial dimension. Bolted flanges with better positioning ability are designed to place in sections without space limitation. A series of leak rate and outgassing rate measurements were performed, and force and finite element analyses were carried out. Leak rates of both two flanges are lower than 5×10−13Pam3s−1 after 10 times seal-changing tests and 15 times same-seal bakeout cycles. Required fastening torques of chain clamp and bolted flange are 5–7 N m and 3–5 N m, respectively, in order to achieve sealing. The outgassing rate of CuCrZr is about an order of magnitude less than that of stainless steel after bakeout to 250 °C. The simulation results indicate that stress on the CuCrZr flange is far lower than metal C-ring due to the large deformation of the seal.

Image processing techniques to estimate weight and morphological parameters for selected wheat refractions

The geometric and color features of agricultural material along with related physical properties are critical to characterize and express its physical quality. The experiments were conducted to classify the physical characteristics like size, shape, color and texture and then workout the relationship between manual observations and using image processing techniques for weight and volume of the four wheat refractions i.e. sound, damaged, shriveled and broken grains of wheat variety PBW 725. A flatbed scanner was used to acquire the images and digital image processing method was used to process the images and output of image analysis was compared with the actual measurements data using digital vernier caliper. A linear relationship was observed between the axial dimensions of refractions between manual measurement and image processing method with R2 in the range of 0.798–0.947. The individual kernel weight and thousand grain weight of the refractions were observed to be in the range of 0.021–0.045 and 12.56–46.32 g respectively. Another linear relationship was found between individual kernel weight and projected area estimated using image processing methodology with R2 in the range of 0.841–0.920. The sphericity of the refractions varied in the range of 0.52–0.71. Analyses of the captured images suggest ellipsoid shape with convex geometry while the same observation was recorded by physical measurements also. A linear relationship was observed between the volume of refractions derived from measured dimensions and calculated from image with R2 in the range of 0.845–0.945. Various color and grey level co-variance matrix texture features were extracted from acquired images using the open-source Python programming language and OpenCV library which can exploit different machine and deep learning algorithms to properly classify these refractions.

Salvage Resection and Intracranial Cesium-131 Brachytherapy for Brain Tumors

Management of progressive brain tumors following high dose radiotherapy is controversial. In select cases, surgical resection can provide rapid relief of regional mass effect and edema, and highly focal adjuvant re-irradiation can be administered in the form of brachytherapy. Permanent low-dose rate cesium-131 brachytherapy may offer dosimetric and radiobiologic advantages over other isotopes. The purpose of this study was to examine the safety and efficacy of intracranial cesium-131 brachytherapy after surgical resection in a heavily pre-treated patient cohort.A retrospective chart review was conducted of all patients treated with intraoperative intracranial cesium-131 brachytherapy from an institutional database. Treatment consisted of maximal safe resection followed by implantation of suture-stranded cesium-131 seeds, maintaining approximately 10mm spacing between seeds, with a planned target dose of 80 Gy to 5mm depth. Local failure was defined as recurrence in or contacting the resection cavity after salvage resection and brachytherapy. Regional failure was defined as recurrence within 10mm of the resection cavity. Recurrence was defined as a new lesion or growth of ≥25% in any axial dimension on interval MRI. Toxicity was collected based on CTCAE 4.0.A total of 35 patients with a median imaging follow up of 17.0 months (interquartile range [IQR] 9.7-25.9) underwent 41 consecutive cesium-131 implants between 2016 and 2020. 20 patients (59%; N = 22 implants) were treated for recurrent brain metastasis, 12 patients (34%; N = 16 implants) were treated for recurrent atypical (N = 8) or anaplastic meningioma (N = 4), and 3 patients (9%) were treated for recurrent glioma (N = 2) or hemangiopericytoma (N = 1). A majority of lesions had received prior surgery (N = 28, 66.7%, range 0-3 prior surgeries) and 34 patients had received prior high dose radiation. 34 of 41 (82.9%) tumors had received prior radiosurgery, and 12 (29.2%) had undergone prior external beam radiation (range 50-60 Gy). 17 of 41 lesions (41.5%) had radiologic evidence of adverse radiation/treatment effect (ARE) prior to salvage therapy. Median tumor size was 3.0cm (IQR 2.3-3.7). Overall actuarial local/loco-regional control at 1-year was 91.6%/84.7% (89.8%/88.9% for metastases and 100%/82.5% for meningiomas). Crude loco-regional control was 86.3% for metastases, 75% for meningiomas, and 66.7% for other lesions. Symptomatic ARE following treatment was observed in 9.8% (N = 4) resection cavities. The surgical complication rate was 14.6% (N = 6 total, N = 3 [7.3%] grade 3-5) including 1 peri-operative death.Cesium-131 brachytherapy in this heavily pre-treated cohort resulted in good local control and an acceptable rate of symptomatic adverse radiation effect and toxicity and may be a reasonable treatment option for this select population.W.C. Chen: None. M. Lafreniere: None. C. Phuong: None. M. Lometti: None. O. Morin: None. B.P. Ziemer: None. H. Vasudevan: Research Grant; Children's Tumor Foundation. Patent/License Fees/Copyright; Genentech, Eli Lilly. S. Hervey-Jumper: None. P.V. Theodosopoulos: None. S. Magill: None. S.E. Fogh: Independent Contractor; Accuray. J.L. Nakamura: None. L. Boreta: None. P.K. Sneed: None. M.W. McDermott: Chair; Miami Baptist. D. Raleigh: None. S.E. Braunstein: Advisory Board; Radiation Oncology Questions, LLC.

Continuing Education Needs Identified During the Initial Experience of Delivering 3D Conformal Radiotherapy for Cervical Cancer Patients in Tanzania

In resource-limited settings where experience with 3D conformal radiation therapy (3DCRT) is still growing, review of simulation CTs and radiation therapy plans may illuminate topics for continuing education. We conducted a review of an early cohort of cervical cancer patients treated with 3DCRT in Tanzania to identify education needs that may be generalizable to similar resource-limited settings.In Tanzania, 3DCRT capabilities began in August 2018. A retrospective review of 30 consecutive patients who received definitive whole pelvis 3DCRT for cervical cancer from 2019 to 2020 was conducted after IRB approval. Each patient's simulation CT was evaluated for evidence of advanced disease not detected on initial diagnostic work-up, including pelvic or para-aortic lymphadenopathy (LAD) defined as axial dimension > = 1 cm. An independent set of contours was generated according to United States national consensus guidelines. DICE similarity coefficient (DSC) agreement analysis was conducted between contours. As non-systematic variations in planning target volume (PTV) labelling, summations, and expansions precluded direct comparisons, only clinical target volume (CTV) contours were compared in this analysis. Clinically treated 3DCRT plans were evaluated using original and consensus-based contours, and dosimetric coverage was compared using Wilcoxon signed-rank testing.Simulation CT was the sole means of pre-treatment cross-sectional abdominopelvic imaging in 24/30 patients (80%). The pre-simulation clinical stages were FIGO IB (n = 6), IIA (n = 10), IIB (n = 12), IIIA (n = 1), and IVA (n = 1). Simulation CT upstaged 20 of 30 patients (66.7%) to IIIC1 or IIIC2 disease, identifying eight patients with para-aortic LAD and 13 patients with pelvic LAD. Agreement analysis between clinical and consensus-based contours revealed high agreement in the primary CTV (DSC median 0.83, IQR 0.68 - 0.87), bladder (0.93, IQR 0.88 - 0.95), and femur (0.86) contours, but lower agreement in lymph node CTV (CTVn) contours (DSC 0.59, IQR 0.46 - 0.67). The median volume of clinical-CTVn covered by 45 Gy was 99.7% (IQR 97.5 - 100) while the median volume of consensus-CTVn covered by 45 Gy was 83.3% (IQR 80.1 - 90.1) (P < 0.001). The most frequently undercovered regions were the superior and inferior pre-sacral nodal regions.In resource-limited settings, early case review after 3DCRT initiation may reveal key elements in radiation planning that can guide continuing education topics. In our setting, high yield interventions include systematic evaluation of pelvic and para-aortic LAD on simulation CTs, educational refreshers about nodal contouring, and development of resource-appropriate treatment paradigms when advanced nodal disease is detected.

Novel Application of Long Short-Term Memory Network for 3D to 2D Retinal Vessel Segmentation in Adaptive Optics—Optical Coherence Tomography Volumes

Adaptive optics—optical coherence tomography (AO-OCT) is a non-invasive technique for imaging retinal vascular and structural features at cellular-level resolution. Whereas retinal blood vessel density is an important biomarker for ocular diseases, particularly glaucoma, automated blood vessel segmentation tools in AO-OCT have not yet been explored. One reason for this is that AO-OCT allows for variable input axial dimensions, which are not well accommodated by 2D-2D or 3D-3D segmentation tools. We propose a novel bidirectional long short-term memory (LSTM)-based network for 3D-2D segmentation of blood vessels within AO-OCT volumes. This technique incorporates inter-slice connectivity and allows for variable input slice numbers. We compare this proposed model to a standard 2D UNet segmentation network considering only volume projections. Furthermore, we expanded the proposed LSTM-based network with an additional UNet to evaluate how it refines network performance. We trained, validated, and tested these architectures in 177 AO-OCT volumes collected from 18 control and glaucoma subjects. The LSTM-UNet has statistically significant improvement (p &lt; 0.05) in AUC (0.88) and recall (0.80) compared to UNet alone (0.83 and 0.70, respectively). LSTM-based approaches had longer evaluation times than the UNet alone. This study shows that a bidirectional convolutional LSTM module improves standard automated vessel segmentation in AO-OCT volumes, although with higher time cost.

851 Giant Oncocytoma In A Solitary Kidney: A Case Report on Balancing Surgical Resection Against Surveillance

Abstract Renal oncocytomas are benign kidney neoplasms that are typically small, unilaterally localised (95%) and challenging to differentiate on cross-sectional imaging, hence requiring surgical intervention. We herein present the extremely rare case of a patient with giant, bilateral oncocytomas and oncocytosis, and chronic kidney disease (CKD) and discuss the associated treatment challenges. A 61-year-old male with no past medical history presented with CKD (eGFR of 32ml/min). On investigation, cross sectional imaging revealed bilateral, multifocal, solid and vascular renal lesions. The largest lesion measuring 115mm x 102mm was situated in the right kidney, with multiple lesions noted in the left kidney, measuring up to 44mm. He subsequently underwent a right radical nephrectomy and histopathological analysis reported oncocytosis of the background kidney. The largest left sided renal lesion was biopsied, also confirmatory of benign oncocytoma. eGFR after surgery was 26ml/min. Following patient-centric consultations, further surgical intervention for the left sided renal lesions was declined, aiming to avoid renal replacement therapy (RRT). He has remained on active surveillance with biannual scans for 6 years. The lesions in his remaining kidney have since grown and coalesced into a single large lesion, with axial dimensions in the most recent MRI scan of 104mm x 306mm. He has progressed to stage IV CKD (eGFR 16ml/min), but still currently without need of RRT. This case study underscores both the significance of shared decision making in urology and surgery. Ultimately, the most significant skill lies in knowing when to not operate, especially when presented with the rarest of cases.

Spectrally Gated Microscopy (SGM) with Meta Optics for Parallel Three-Dimensional Imaging.

Volumetric imaging with high spatiotemporal resolution is of utmost importance for various applications ranging from aerospace and defense to real-time imaging of dynamic biological processes. To facilitate three-dimensional sectioning, current technology relies on mechanisms to reject light from adjacent out-of-focus planes either spatially or by other means. Yet, the combination of rapid acquisition time and high axial resolution is still elusive, motivating a persistent pursuit for emerging imaging approaches. Here we introduce and experimentally demonstrate a concept named spectrally gated microscopy (SGM), which enables a single-shot interrogation over the full axial dimension while maintaining a submicron sectioning resolution. SGM utilizes two important features enabled by flat optics (i.e., metalenses or diffractive lenses), namely, a short focal length and strong chromatic aberrations. Using SGM we demonstrate three-dimensional imaging of millimeter-scale samples while scanning only the lateral dimension, presenting a significant advantage over state-of-the-art technology.

Long-Wavelength-Filtered Light Transiently Inhibits Negative Lens-Induced Axial Eye Growth in the Chick Myopia Model.

PurposeEye growth and myopia development in chicks, and some other animal models, can be suppressed by rearing under near-monochromatic, short-wavelength blue light. We aimed to determine whether similar effects could be achieved using glass filters that transmit a broader range of short and middle wavelengths.MethodsOn day 6 or 7 post-hatch, 169 chicks were assigned to one of three monocular lens conditions (−10 D, +10 D, plano) and reared for 7 or 10 days under one of four 201-lux lighting conditions: (1) B410 long-wavelength–filtered light, (2) B460 long-wavelength–filtered light, (3) Y48 short-wavelength–filtered light, or (4) HA50 broadband light.ResultsAt 7 days, B410 (but not B460) long-wavelength–filtered light had significantly inhibited negative lens induced axial growth relative to Y48 short-wavelength–filtered light (mean difference in experimental eye = −0.249 mm; P = 0.006) and HA50 broadband light (mean difference = −0.139 mm; P = 0.038). B410 filters also inhibited the negative lens-induced increase in vitreous chamber depth relative to all other filter conditions. Corresponding changes in refraction did not occur, and biometric measurements in a separate cohort of chicks suggested that the axial dimension changes were transient and not maintained at 10 days.ConclusionsChromatic effects on eye growth can be achieved using filters that transmit a broad range of wavelengths even in the presence of strong cues for myopia development.Translational RelevanceBroad-wavelength filters that provide a more “naturalistic” visual experience relative to monochromatic light have potential to alter myopia development, although the effects shown here were modest and transient and require exploration in further species.