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Keywords = orbital volume measurement

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22 pages, 10230 KiB  
Article
Near-Surface Water Vapor Content Based on SPICAV IR/VEx Observations in the 1.1 and 1.18 μm Transparency Windows of Venus
by Daria Evdokimova, Anna Fedorova, Nikolay Ignatiev, Oleg Korablev, Franck Montmessin and Jean-Loup Bertaux
Atmosphere 2025, 16(6), 726; https://doi.org/10.3390/atmos16060726 - 15 Jun 2025
Cited by 1 | Viewed by 411
Abstract
The SPICAV IR spectrometer aboard the Venus Express orbiter measured spectra of the 1.1 and 1.18 μm atmospheric transparency windows at the Venus night side in 2006–2014. The long-term measurements encompassed the major part of the Venus globe, including polar latitudes. For the [...] Read more.
The SPICAV IR spectrometer aboard the Venus Express orbiter measured spectra of the 1.1 and 1.18 μm atmospheric transparency windows at the Venus night side in 2006–2014. The long-term measurements encompassed the major part of the Venus globe, including polar latitudes. For the first time, the H2O volume mixing ratio in the deep Venus atmosphere at about 10–16 km has been retrieved for the entire SPICAV IR dataset using a radiative transfer model with multiple scattering. The retrieved H2O volume mixing ratio is found to be sensitive to different approximations of the H2O and CO2 absorption lines’ far wings and assumed surface emissivity. The global average of the H2O abundance retrieved for different parameters ranges from 23.6 ± 1.0 ppmv to 27.7 ± 1.2 ppmv. The obtained values are consistent with recent studies of water vapor below the cloud layer, showing the H2O mixing ratio below 30 ppmv. Within the considered dataset, the zonal mean of the H2O mixing ratio does not vary significantly from 60° S to 75° N, except for a 2 ppmv decrease noted at high latitudes. The H2O local time distribution is also uniform. The 8-year observation period revealed no significant long-term trends or periodicities. Full article
(This article belongs to the Section Planetary Atmospheres)
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17 pages, 2156 KiB  
Article
Comparison of Anatomical Maxillary Sinus Implant and Polydioxanone Sheets in Treatment of Orbital Floor Blowout Fractures: A Retrospective Cohort Study
by Benjamin Walch, Alexander Gaggl, Gian Battista Bottini, Johannes Hachleitner, Florian Huber, Hannes Römhild, Martin Geroldinger and Maximilian Götzinger
J. Funct. Biomater. 2025, 16(6), 204; https://doi.org/10.3390/jfb16060204 - 2 Jun 2025
Viewed by 694
Abstract
Background: Orbital floor blowout fractures (OFBF) can have serious consequences for the patient. Selecting the right treatment method and materials is essential. Krenkel’s maxillary sinus implant has been used successfully for more than 40 years in clinical practice. The aim of this study [...] Read more.
Background: Orbital floor blowout fractures (OFBF) can have serious consequences for the patient. Selecting the right treatment method and materials is essential. Krenkel’s maxillary sinus implant has been used successfully for more than 40 years in clinical practice. The aim of this study was to evaluate the long-term outcome of this implant compared to polydioxanone (PDS) sheets. Material and methods: This retrospective study examined a cohort of 82 OFBF patients over a seven-year period. Clinical and geometric data were collected. Defect size, location, and the volume of the herniated tissue were measured from conventional computer tomography (CT) or cone beam computer tomography (CBCT) scans. The relationship between ophthalmologic rehabilitation and treatment modality was analyzed using logistic regression. Results: The study included 82 patients, 28% female and 72% male, with a median age of 45.2 years. Defect size and hernia volume correlated with preoperative ophthalmological symptoms. At follow-up, 14.8% in the implant group and 28.6% in the PDS group showed mild visual impairment, with no severe diplopia. Conclusions: Our results suggest this method is a reliable and effective solution for repairing OFBFs and ophthalmologic rehabilitation. However, further research in a clinical controlled trial is needed. Full article
(This article belongs to the Section Biomaterials and Devices for Healthcare Applications)
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21 pages, 4865 KiB  
Article
Therapeutic Potential of Umbilical Cord MSC-Derived Exosomes in a Severe Dry Eye Rat Model: Enhancing Corneal Protection and Modulating Inflammation
by Sze-Min Chan, Chris Tsai, Tai-Ping Lee, Zih-Rou Huang, Wei-Hsiang Huang and Chung-Tien Lin
Biomedicines 2025, 13(5), 1174; https://doi.org/10.3390/biomedicines13051174 - 11 May 2025
Cited by 1 | Viewed by 1178
Abstract
Background/Objectives: Dry eye disease (DED) is a multifactorial inflammatory disease that disrupts the ocular surface, causing tear film instability, epithelial damage, and chronic inflammation. Mesenchymal stem cell-derived exosomes (MSC-exos) are promising therapeutics with immunomodulatory and regenerative properties. This study investigates the therapeutic [...] Read more.
Background/Objectives: Dry eye disease (DED) is a multifactorial inflammatory disease that disrupts the ocular surface, causing tear film instability, epithelial damage, and chronic inflammation. Mesenchymal stem cell-derived exosomes (MSC-exos) are promising therapeutics with immunomodulatory and regenerative properties. This study investigates the therapeutic effects of umbilical cord MSC-derived exosomes (UCMSC-exos) in a severe dry eye model, induced by a surgical resection of the infra-orbital (ILG) and extra-orbital lacrimal gland (ELG) in rats. Methods: Clinical evaluations, including tear volume measurement, slit lamp biomicroscopy, fluorescein staining, and spectral domain optical coherence tomography (SD-OCT), were performed to assess corneal neovascularization, corneal abrasion, and epithelial/stromal thickness. Histopathological analysis, immunohistochemistry, and mRNA gene expression were conducted to evaluate corneal tissue changes and inflammatory marker expression. Results: The results show that the treatment group exhibited significantly reduced corneal neovascularization compared to the control group (p = 0.030). During the first month, the Exo group also had a significantly lower corneal fluorescein staining area (p = 0.032), suggesting accelerated wound healing. SD-OCT analysis revealed that the corneal epithelial thickness in the treatment group was closer to normal levels compared to the control group (p = 0.02 and p = 0.006, respectively). UCMSC-exos treatment also modulated the expression of α-SMA and apoptosis in the cornea. Additionally, the gene expression of inflammatory cytokines (IL-1β and TNF-α) were downregulated. Conclusions: These findings suggest that MSC-exosome therapy offers a novel, cell-free regenerative approach for managing severe DED, modulating inflammatory response. Full article
(This article belongs to the Section Cell Biology and Pathology)
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11 pages, 2239 KiB  
Article
Relationship Between Ocular Trauma Score and Computed Tomography Findings in Eyes with Penetrating Globe Injuries: A Preliminary Study
by Berire Şeyma Durmuş Ece, Zübeyir Yozgat, Yusuf İnançlı, Bunyamin Ece and Sonay Aydin
Diagnostics 2025, 15(7), 830; https://doi.org/10.3390/diagnostics15070830 - 25 Mar 2025
Viewed by 504
Abstract
Background/Objectives: The aim of this study was to evaluate computed tomography (CT) findings in penetrating globe injuries and their relationship with ocular trauma scores (OTSs). Methods: Patients with penetrating globe injuries who had orbital CT images were included in this study. [...] Read more.
Background/Objectives: The aim of this study was to evaluate computed tomography (CT) findings in penetrating globe injuries and their relationship with ocular trauma scores (OTSs). Methods: Patients with penetrating globe injuries who had orbital CT images were included in this study. Demographics, injury zone, and ophthalmologic exam data were collected retrospectively. OTSs and categories were determined. Orbital CT images were evaluated by a radiologist to determine decreased globe volume, globe wall irregularity, chorioretinal layer thickening, lens dislocation, asymmetric anterior chamber depth (ACD), abnormal vitreous density, and intraocular air presence. Results: This study included 30 eyes of 30 patients. The majority of patients (n = 20, 66.7%) had Zone I injuries. The most common CT findings were globe wall irregularity (53.3%) and asymmetric ACD (53.3%). No CT findings were observed in 10 patients (33.3%). Globe wall irregularity was the most frequent CT finding in the OTS II category, while asymmetric ACD was most frequent in the OTS IV category. All patients with decreased globe volume, lens dislocation, abnormal vitreous density, and ≥3 CT findings were in the OTS II category. A significant negative correlation was found between the number of CT findings and OTS (r = −0.644, p < 0.001), and a significant positive correlation was found between the number of CT findings and clinically measured wound size (r = 0.600, p < 0.001). Conclusions: CT findings help assess ocular trauma severity, but clinical examination remains essential for accurate diagnosis. Full article
(This article belongs to the Special Issue Recent Advances in Computed Tomography Imaging for Clinical Diagnosis)
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9 pages, 228 KiB  
Proceeding Paper
Beyond Mitigation: New Metrics for Space Sustainability Assessment
by Sara Qaddoumi, Ernestina Cianca, Mauro De Sanctis, Tommaso Rossi, Kathiravan Thangavel and Marina Ruggieri
Eng. Proc. 2025, 90(1), 42; https://doi.org/10.3390/engproc2025090042 - 14 Mar 2025
Viewed by 429
Abstract
The escalating volume of space operations and the proliferation of satellites underscore the urgent need for a pivotal shift towards sustainable space use. This paper highlights the importance of addressing space sustainability through a holistic framework. Robust international commitments, aligned with the United [...] Read more.
The escalating volume of space operations and the proliferation of satellites underscore the urgent need for a pivotal shift towards sustainable space use. This paper highlights the importance of addressing space sustainability through a holistic framework. Robust international commitments, aligned with the United Nations Sustainable Development Goals (SDGs) 12 (Responsible Consumption and Production) and 13 (Climate Action), alongside the implementation of legislative measures, are essential for fostering responsible and sustainable practices in space activities. Furthermore, innovative technology advancements can potentially convert this space sustainability problem into an opportunity for the space sector. Mitigating the risk of debris is no longer sufficient. This article advocates for prioritizing sustainability in the design phase of the new missions and constellations. To achieve this objective, it is crucial to develop a comprehensive understanding of how various design parameters—such as orbital altitude, the number of satellites, the inclusion or exclusion of inter-satellite links, system interoperability, and reconfigurability—impact the sustainability of space systems. Hence, the investigation suggests creating innovative Key Performance Indicators (KPIs) that specifically target space sustainability. These KPIs would enable the evaluation of specific missions/constellations and the comparison of different design alternatives. The absence of current research on these KPIs requires the creation of new ones. This research introduces a preliminary framework for establishing these novel metrics, which can be vital for governments and companies to develop and oversee a sustainable future in space. By implementing a holistic strategy combining robust policy frameworks with cutting-edge technology solutions, we can guarantee the ongoing, secure, and environmentally responsible space utilization for future generations. Full article
52 pages, 15198 KiB  
Article
Differences in Anatomical Structures and Resting-State Brain Networks Between Elite Wrestlers and Handball Athletes
by Fatma Sahin Ozarslan and Adil Deniz Duru
Brain Sci. 2025, 15(3), 285; https://doi.org/10.3390/brainsci15030285 - 7 Mar 2025
Cited by 1 | Viewed by 1042
Abstract
Background/Objectives: Advancements in biomedical imaging technologies over the past few decades have made it increasingly possible to measure the long-term effects of exercise on the central nervous system. This study aims to compare the brain morphology and functional connectivity of wrestlers and handball [...] Read more.
Background/Objectives: Advancements in biomedical imaging technologies over the past few decades have made it increasingly possible to measure the long-term effects of exercise on the central nervous system. This study aims to compare the brain morphology and functional connectivity of wrestlers and handball players, exploring sport-specific neural adaptations. Methods: Here, we examined 26 elite male athletes (13 wrestlers and 13 handball players) using anatomical and resting-state functional magnetic resonance imaging (fMRI) measurements. Connectivity maps are derived using the seed-based correlation analysis of resting-state fMRI, while voxel-based morphometry (VBM) is employed to identify anatomical differences. Additionally, the cortical thickness and global volumetric values of the segmented images are examined to determine the distinctions between elite wrestlers and handball players using non-parametric statistical tests. Results: Wrestlers exhibited greater grey matter volume (GMV) in the right middle temporal gyrus, left middle frontal gyrus, and right posterior cingulate gyrus (uncorr., p < 0.001). On the other hand, wrestlers showed increased functional connectivity in the left superior temporal gyrus, left parahippocampal gyrus, the left anterior orbital gyrus, and right superior frontal gyrus–medial frontal region (P(FWE) < 0.05). In addition, wrestlers showed greater cortical thickness in several brain regions. Conclusions: The increased GMV, cortical thickness, and functional connectivity observed in wrestlers highlight the presence of sport-specific neural adaptations. While this research provides valuable insights into the neuroplastic effects of various athletic disciplines, further studies involving additional sports and control groups are needed for a more comprehensive understanding. Full article
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17 pages, 1272 KiB  
Article
Segmentation-Based Measurement of Orbital Structures: Achievements in Eyeball Volume Estimation and Barriers in Optic Nerve Analysis
by Yong Oh Lee, Hana Kim, Yeong Woong Chung, Won-Kyung Cho, Jungyul Park and Ji-Sun Paik
Diagnostics 2024, 14(23), 2643; https://doi.org/10.3390/diagnostics14232643 - 23 Nov 2024
Viewed by 995
Abstract
Background/Objective: Orbital diseases often require precise measurements of eyeball volume, optic nerve sheath diameter (ONSD), and apex-to-eyeball distance (AED) for accurate diagnosis and treatment planning. This study aims to automate and optimize these measurements using advanced deep learning segmentation techniques on orbital Computed [...] Read more.
Background/Objective: Orbital diseases often require precise measurements of eyeball volume, optic nerve sheath diameter (ONSD), and apex-to-eyeball distance (AED) for accurate diagnosis and treatment planning. This study aims to automate and optimize these measurements using advanced deep learning segmentation techniques on orbital Computed Tomography (CT) scans. Methods: Orbital CT datasets from individuals of various age groups and genders were used, with annotated masks for the eyeball and optic nerve. A 2D attention U-Net architecture was employed for segmentation, enhanced with slice-level information embeddings to improve contextual understanding. After segmentation, the relevant metrics were calculated from the segmented structures and evaluated for clinical applicability. Results: The segmentation model demonstrated varying performance across orbital structures, achieving a Dice score of 0.8466 for the eyeball and 0.6387 for the optic nerve. Consequently, eyeball-related metrics, such as eyeball volume, exhibited high accuracy, with a root mean square error (RMSE) of 1.28–1.90 cm3 and a mean absolute percentage error (MAPE) of 12–21% across different genders and age groups. In contrast, the lower accuracy of optic nerve segmentation led to less reliable measurements of optic nerve sheath diameter (ONSD) and apex-to-eyeball distance (AED). Additionally, the study analyzed the automatically calculated measurements from various perspectives, revealing key insights and areas for improvement. Conclusions: Despite these challenges, the study highlights the potential of deep learning-based segmentation to automate the assessment of ocular structures, particularly in measuring eyeball volume, while leaving room for further improvement in optic nerve analysis. Full article
(This article belongs to the Special Issue Deep Learning in Medical Image Segmentation and Diagnosis)
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13 pages, 4597 KiB  
Article
Anatomical Measurements of the Malar Bone for Safe Zygomatic Implant Placement: A Study on Donated Bodies
by Carlo Barausse, Pietro Felice, Roberto Pistilli, Gerardo Pellegrino, Lorenzo Bonifazi, Subhi Tayeb, Antonietta Fazio, Maria Vittoria Marvi, Lucia Manzoli and Stefano Ratti
J. Clin. Med. 2024, 13(22), 6798; https://doi.org/10.3390/jcm13226798 - 12 Nov 2024
Cited by 3 | Viewed by 1493
Abstract
Background: The malar bone provides an anchorage point for zygomatic implants, avoiding invasive reconstructive surgeries in the fixed rehabilitation of fully edentulous and severely atrophic maxillae. The limited bone volume, however, requires precise implant placement to prevent complications related to nearby anatomical [...] Read more.
Background: The malar bone provides an anchorage point for zygomatic implants, avoiding invasive reconstructive surgeries in the fixed rehabilitation of fully edentulous and severely atrophic maxillae. The limited bone volume, however, requires precise implant placement to prevent complications related to nearby anatomical structures. This observational cross-sectional study aims to measure the malar and zygomatic arch bones and their distances from critical anatomical landmarks to guide surgeons in safe zygomatic implant placement. Methods: Dissections were performed bilaterally on 29 heads from human donated bodies in a cross-sectional observational study. Key landmarks evaluated include the infraorbital foramen (IF), pyriform nasal aperture (PNA), infraorbital margin (IM), zygomaticofacial foramen (ZFF), anterior end (A), and the most protruding point of the zygomatic arch (B). Measurements included IF-PNA, IF-IM, IF-ZFF, ZFF-IM, A-B, and orbital floor depth (OFD). Results: Significant findings showed IF-PNA was greater in males (18.66 ± 2.63 mm, p = 0.001), and IF-ZFF varied between sides (26.72 ± 8.7 mm, p = 0.002). ZFF-IM was larger in males (7.43 ± 2.09 mm, p < 0.001). Heights and thicknesses were also assessed, with significant side differences observed. Conclusions: These findings underscore the importance of understanding precise anatomical distances for successful implant placement. The study provides essential data to enhance surgical planning and training, ensuring safer procedures and minimizing the risk of complications. Full article
(This article belongs to the Special Issue Dental Implantology: Clinical Updates and Perspectives)
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32 pages, 1586 KiB  
Article
The Magellanic Clouds Are Very Rare in the IllustrisTNG Simulations
by Moritz Haslbauer, Indranil Banik, Pavel Kroupa, Hongsheng Zhao and Elena Asencio
Universe 2024, 10(10), 385; https://doi.org/10.3390/universe10100385 - 1 Oct 2024
Cited by 3 | Viewed by 1121
Abstract
The Large and Small Magellanic Clouds (LMC and SMC) form the closest interacting galactic system to the Milky Way, therewith providing a laboratory to test cosmological models in the local Universe. We quantify the likelihood for the Magellanic Clouds (MCs) to be observed [...] Read more.
The Large and Small Magellanic Clouds (LMC and SMC) form the closest interacting galactic system to the Milky Way, therewith providing a laboratory to test cosmological models in the local Universe. We quantify the likelihood for the Magellanic Clouds (MCs) to be observed within the ΛCDM model using hydrodynamical simulations of the IllustrisTNG project. The orbits of the MCs are constrained by proper motion measurements taken by the Hubble Space Telescope and Gaia. The MCs have a mutual separation of dMCs=24.5kpc and a relative velocity of vMCs=90.8kms1, implying a specific phase-space density of fMCs,obs(dMCs·vMCs)3=9.10×1011km3s3kpc3. We select analogues to the MCs based on their stellar masses and distances in MW-like halos. None of the selected LMC analogues have a higher total mass and lower Galactocentric distance than the LMC, resulting in >3.75σ tension. We also find that the fMCs distribution in the highest resolution TNG50 simulation is in 3.95σ tension with observations. Thus, a hierarchical clustering of two massive satellites like the MCs in a narrow phase-space volume is unlikely in ΛCDM, presumably because of short merger timescales due to dynamical friction between the overlapping dark matter halos. We show that group infall led by an LMC analogue cannot populate the Galactic disc of satellites (DoS), implying that the DoS and the MCs formed in physically unrelated ways in ΛCDM. Since the 20 alignment of the LMC and DoS orbital poles has a likelihood of P=0.030 (2.17σ), adding this χ2 to that of fMCs gives a combined likelihood of P=3.90×105 (4.11σ). Full article
(This article belongs to the Special Issue Universe: Feature Papers 2024—"Galaxies and Clusters")
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11 pages, 2623 KiB  
Article
Evaluation of the Effect of Topical Prostaglandin Analog Treatment on Orbital Structures in Open-Angle Glaucoma with Computed Tomography
by Berire Şeyma Durmuş Ece, Zübeyir Yozgat, Hüseyin Bayramlı, Bunyamin Ece and Sonay Aydin
J. Clin. Med. 2024, 13(19), 5808; https://doi.org/10.3390/jcm13195808 - 28 Sep 2024
Cited by 2 | Viewed by 1950
Abstract
Background/Objectives: This study aims to evaluate the computed tomography (CT) scans of glaucoma patients using prostaglandin analogs (PGA) in one eye, investigate findings associated with prostaglandin-associated periorbitopathy (PAP), and compare these findings with those of the contralateral eyes. Methods: Patients with [...] Read more.
Background/Objectives: This study aims to evaluate the computed tomography (CT) scans of glaucoma patients using prostaglandin analogs (PGA) in one eye, investigate findings associated with prostaglandin-associated periorbitopathy (PAP), and compare these findings with those of the contralateral eyes. Methods: Patients with open-angle glaucoma who had CT images of the orbital region taken for another reason at least one month after starting PGA treatment in one eye were included in the study. Enophthalmos measurements from thin-slice CT images, along with 3D volume measurements of orbital fat tissue, periorbital muscles, and the optic nerve, were performed. Ophthalmological examination findings and treatment information were collected. The values were compared with those of the contralateral eyes of the same patients not using PGA. Intraclass correlation coefficients (ICCs) were computed to evaluate measurement repeatability. Results: Forty patients were included in the study. Among them, 29 (72.5%) used latanoprost, 9 (22.5%) used bimatoprost, and 2 (5%) used travoprost. The mean enophthalmos values on the treated side (15.5 ± 2.0 mm) were lower than on the untreated side (16.1 ± 1.4 mm), but this difference was not statistically significant (p = 0.07). In 29 patients (72.5%), enophthalmos measurements were smaller on the treated side, with 7 patients (17.5%) showing a difference of 2 mm or more. No significant correlation was found between the duration of PGA use and enophthalmos measurements (p = 0.768 r = −0.048). Additionally, no significant differences were found in orbital fat volume, total extraocular muscle volume, and optic nerve volume (p > 0.05). ICC values demonstrated excellent reliability (ICC > 0.75) for all measurements. Conclusions: We did not find significant differences in enophthalmos measurements, orbital fat volume, total muscle volume, and optic nerve volume between the PGA-treated and untreated eyes. Full article
(This article belongs to the Special Issue Diagnosis, Treatment, and Prevention of Glaucoma: Second Edition)
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27 pages, 4239 KiB  
Article
Code-Based Differential GNSS Ranging for Lunar Orbiters: Theoretical Review and Application to the NaviMoon Observables
by Anaïs Delépaut, Alex Minetto and Fabio Dovis
Remote Sens. 2024, 16(15), 2755; https://doi.org/10.3390/rs16152755 - 28 Jul 2024
Cited by 3 | Viewed by 1819
Abstract
In the near future, international space agencies have planned to achieve significant milestones in investigating the utilization of Global Navigation Satellite Systems (GNSS) within and beyond the current space service volume up to their application to lunar missions. These initiatives aim to demonstrate [...] Read more.
In the near future, international space agencies have planned to achieve significant milestones in investigating the utilization of Global Navigation Satellite Systems (GNSS) within and beyond the current space service volume up to their application to lunar missions. These initiatives aim to demonstrate the feasibility of GNSS navigation at lunar altitudes. Based on the outcomes of such demonstrations, dozens of lunar missions will likely be equipped with a GNSS receiver to support autonomous navigation in the lunar proximity. Relying on non-invasive, consolidated differential techniques, GNSS will enable baseline estimation, thus supporting a number of potential applications to lunar orbiters such as collaborative navigation, formation flight, orbital manoeuvers, remote sensing, augmentation systems and beyond. Unfortunately, the large dynamics and the geometry of such differential GNSS scenarios set them apart from current terrestrial and low-earth orbit use cases. These characteristics result in an increased sensitivity to measurements time misalignment among orbiters. Hence, this paper offers a review of baseline estimation methods and characterizes the divergences and limitations w.r.t. to terrestrial applications. The study showcases the estimation of the baseline length between a lunar CubeSat mission, VMMO, and the communication relay Lunar Pathfinder mission. Notably, real GNSS measurements generated by an Engineering Model of the NaviMoon receiver in the European Space Agency (ESA/ESTEC) Radio Navigation Laboratory are utilized. A radio-frequency constellation simulator is used to generate the GNSS signals in these hardware-in-the-loop tests. The performed analyses showed the invalidity of common terrestrial differential GNSS ranging techniques for space scenarios due to the introduction of significant biases. Improved ranging algorithms were proposed and their potential to cancel ranging errors common to both receivers involved was confirmed. Full article
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12 pages, 1331 KiB  
Article
Are Age and Trauma Mechanism Associated with Volume Change in the Fractures of the Bony Orbit?
by Ella Starck, Niilo Lusila, Juho Suojanen and Eeva Kormi
J. Clin. Med. 2024, 13(12), 3618; https://doi.org/10.3390/jcm13123618 - 20 Jun 2024
Cited by 1 | Viewed by 1167
Abstract
Blowout fractures are common midfacial fractures in which one or several of the bones of orbital vault break. This is usually caused by a direct trauma to the eye with a blunt object such as a fist. Fracturing of the fragile orbital bones [...] Read more.
Blowout fractures are common midfacial fractures in which one or several of the bones of orbital vault break. This is usually caused by a direct trauma to the eye with a blunt object such as a fist. Fracturing of the fragile orbital bones can lead to changes in the orbital volume, which may cause enophthalmos, diplopia, and impaired facial aesthetics. Objectives: The aim of this study is to investigate whether there is an association between volume change of the bony orbit and age, gender, or trauma mechanism. Methods: A retrospective study of patients with unilateral blowout or blow-in fractures treated and examined in Päijät-Häme Central Hospital, Lahti, Finland was conducted. Altogether, 127 patients met the inclusion criteria. Their computed tomographs (CT) were measured with an orbit-specific automated segmentation-based volume measurement tool, and the relative orbital volume change between fractured and intact orbital vault was calculated. Thereafter, a statistical analysis was performed. A p-value less than 0.05 was considered significant. Results: We found that relative increase in orbital volume and age have a statistically significant association (p = 0.022). Trauma mechanism and gender showed no significant role. Conclusions: Patient’s age is associated with increased volume change in fractures of the bony orbit. Full article
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14 pages, 4973 KiB  
Article
Classical Orbital Floor Post-Traumatic Reconstruction vs. Customized Reconstruction with the Support of “In-House” 3D-Printed Models: A Retrospective Study with an Analysis of Volumetric Measurement
by Elvis Kallaverja, Ida Barca, Francesco Ferragina and Maria Giulia Cristofaro
Diagnostics 2024, 14(12), 1248; https://doi.org/10.3390/diagnostics14121248 - 13 Jun 2024
Cited by 1 | Viewed by 1394
Abstract
Background: Orbital floor fractures (OFFs) represent an interesting chapter in maxillofacial surgery, and one of the main challenges in orbit reconstruction is shaping and cutting the precise contour of the implants due to its complex anatomy. Objective: The aim of the retrospective study [...] Read more.
Background: Orbital floor fractures (OFFs) represent an interesting chapter in maxillofacial surgery, and one of the main challenges in orbit reconstruction is shaping and cutting the precise contour of the implants due to its complex anatomy. Objective: The aim of the retrospective study was to demonstrate, through pre- and postoperative volumetric measurements of the orbit, how the use of a preformed titanium mesh based on the stereolithographic model produced with 3D printers (“In-House” reconstruction) provides a better reconstruction volumetric compared to the intraoperatively shaped titanium mesh. Materials and Methods: The patients with OFF enrolled in this study were divided into two groups according to the inclusion criteria. In Group 1 (G1), patients surgically treated for OFF were divided into two subgroups: G1a, patients undergoing orbital floor reconstruction with an intraoperatively shaped mesh, and G1b, patients undergoing orbital floor reconstruction with a preoperative mesh shaped on a 3D-printed stereolithographic model. Group 2 (G2) consisted of patients treated for other traumatic pathologies (mandible fractures and middle face fractures not involving orbit). Pre- and postoperative orbital volumetric measurements were performed on both G1 and G2. The patients of both groups were subjected to the measurement of orbital volume using Osirix software (Pixmeo SARL, CH-1233 Bernex, Switzerland) on the new CT examination. Both descriptive (using central tendency indices such as mean and range) and regressive (using the Bravais–Pearson index, calculated using the GraphPad program) statistical analyses were performed on the recorded data. Results: From 1 January 2017 to 31 December 2021, of the 176 patients treated for OFF at the “Magna Graecia” University Hospital of Catanzaro 10 fulfilled the study’s inclusion criteria: 5 were assigned to G1a and 5 to G1b, with a total of 30 volumetric measurements. In G2, we included 10 patients, with a total of 20 volumetric measurements. From the volumetric measurements and statistical analysis carried out, it emerged that the average of the volumetric differences of the healthy orbits was ±0.6351 cm3, the standard deviation of the volumetric differences was ±0.3383, and the relationship between the treated orbit and the healthy orbit was linear; therefore, the treated orbital volumes tend to approach the healthy ones after surgical treatment. Conclusion: This study demonstrates that if the volume is restored within the range of the standardized mean, the diplopia is completely recovered already after surgery or after one month. For orbital volumes that do not fall within this range, functional recovery could occur within 6 months or be lacking. The restoration of the orbital volume using pre-modeled networks on the patient’s anatomical model, printed internally in 3D, allows for more accurate reconstructions of the orbital floor in less time, with clinical advantages also in terms of surgical timing. Full article
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22 pages, 5307 KiB  
Article
Transfer Learning-Based Specific Emitter Identification for ADS-B over Satellite System
by Mingqian Liu, Yae Chai, Ming Li, Jiakun Wang and Nan Zhao
Remote Sens. 2024, 16(12), 2068; https://doi.org/10.3390/rs16122068 - 7 Jun 2024
Cited by 8 | Viewed by 1561
Abstract
In future aviation surveillance, the demand for higher real-time updates for global flights can be met by deploying automatic dependent surveillance–broadcast (ADS-B) receivers on low Earth orbit satellites, capitalizing on their global coverage and terrain-independent capabilities for seamless monitoring. Specific emitter identification (SEI) [...] Read more.
In future aviation surveillance, the demand for higher real-time updates for global flights can be met by deploying automatic dependent surveillance–broadcast (ADS-B) receivers on low Earth orbit satellites, capitalizing on their global coverage and terrain-independent capabilities for seamless monitoring. Specific emitter identification (SEI) leverages the distinctive features of ADS-B data. High data collection and annotation costs, along with limited dataset size, can lead to overfitting during training and low model recognition accuracy. Transfer learning, which does not require source and target domain data to share the same distribution, significantly reduces the sensitivity of traditional models to data volume and distribution. It can also address issues related to the incompleteness and inadequacy of communication emitter datasets. This paper proposes a distributed sensor system based on transfer learning to address the specific emitter identification. Firstly, signal fingerprint features are extracted using a bispectrum transform (BST) to train a convolutional neural network (CNN) preliminarily. Decision fusion is employed to tackle the challenges of the distributed system. Subsequently, a transfer learning strategy is employed, incorporating frozen model parameters, maximum mean discrepancy (MMD), and classification error measures to reduce the disparity between the target and source domains. A hyperbolic space module is introduced before the output layer to enhance the expressive capacity and data information extraction. After iterative training, the transfer learning model is obtained. Simulation results confirm that this method enhances model generalization, addresses the issue of slow convergence, and leads to improved training accuracy. Full article
(This article belongs to the Section Engineering Remote Sensing)
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18 pages, 6181 KiB  
Article
MR Imaging of Adverse Effects and Ocular Growth Decline after Selective Intra-Arterial Chemotherapy for Retinoblastoma
by Christiaan M. de Bloeme, Sabien van Elst, Paolo Galluzzi, Robin W. Jansen, Joeka de Haan, Sophia Göricke, Annette C. Moll, Joseph C. J. Bot, Francis L. Munier, Maja Beck-Popovic, Francesco Puccinelli, Isabelle Aerts, Theodora Hadjistilianou, Selma Sirin, Mériam Koob, Hervé J. Brisse, Liesbeth Cardoen, Philippe Maeder, Marcus C. de Jong and Pim de Graaf
Cancers 2024, 16(10), 1899; https://doi.org/10.3390/cancers16101899 - 16 May 2024
Cited by 2 | Viewed by 1713
Abstract
This retrospective multicenter study examines therapy-induced orbital and ocular MRI findings in retinoblastoma patients following selective intra-arterial chemotherapy (SIAC) and quantifies the impact of SIAC on ocular and optic nerve growth. Patients were selected based on medical chart review, with inclusion criteria requiring [...] Read more.
This retrospective multicenter study examines therapy-induced orbital and ocular MRI findings in retinoblastoma patients following selective intra-arterial chemotherapy (SIAC) and quantifies the impact of SIAC on ocular and optic nerve growth. Patients were selected based on medical chart review, with inclusion criteria requiring the availability of posttreatment MR imaging encompassing T2-weighted and T1-weighted images (pre- and post-intravenous gadolinium administration). Qualitative features and quantitative measurements were independently scored by experienced radiologists, with deep learning segmentation aiding total eye volume assessment. Eyes were categorized into three groups: eyes receiving SIAC (Rb-SIAC), eyes treated with other eye-saving methods (Rb-control), and healthy eyes. The most prevalent adverse effects post-SIAC were inflammatory and vascular features, with therapy-induced contrast enhancement observed in the intraorbital optic nerve segment in 6% of patients. Quantitative analysis revealed significant growth arrest in Rb-SIAC eyes, particularly when treatment commenced ≤ 12 months of age. Optic nerve atrophy was a significant complication in Rb-SIAC eyes. In conclusion, this study highlights the vascular and inflammatory adverse effects observed post-SIAC in retinoblastoma patients and demonstrates a negative impact on eye and optic nerve growth, particularly in children treated ≤ 12 months of age, providing crucial insights for clinical management and future research. Full article
(This article belongs to the Special Issue Current Progress and Research Trends in Ocular Oncology)
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