Radiation Field Research Articles

A bronchoscopic navigation method based on neural radiation fields.

We introduce a novel approach for bronchoscopic navigation that leverages neural radiance fields (NeRF) to passively locate the endoscope solely from bronchoscopic images. This approach aims to overcome the limitations and challenges of current bronchoscopic navigation tools that rely on external infrastructures or require active adjustment of the bronchoscope. To address the challenges, we leverage NeRF for bronchoscopic navigation, enabling passive endoscope localization from bronchoscopic images. We develop a two-stage pipeline: offline training using preoperative data and online passive pose estimation during surgery. To enhance performance, we employ Anderson acceleration and incorporate semantic appearance transfer to deal with the sim-to-real gap between training and inference stages. We assessed the viability of our approach by conducting tests on virtual bronchscopic images and a physical phantom against the SLAM-based methods. The average rotation error in our virtual dataset is about 3.18 and the translation error is around 4.95 mm. On the physical phantom test, the average rotation and translation error are approximately 5.14 and 13.12 mm. Our NeRF-based bronchoscopic navigation method eliminates reliance on external infrastructures and active adjustments, offering promising advancements in bronchoscopic navigation. Experimental validation on simulation and real-world phantom models demonstrates its efficacy in addressing challenges like low texture and challenging lighting conditions.

Metal line emission around $z<1$ galaxies

We characterize, for the first time, the average extended emission in multiple lines ( and around a statistical sample of 560 galaxies at $z By stacking the Multi Unit Spectroscopic Explorer (MUSE) 3D data from two large surveys, the MUSE Analysis of Gas around Galaxies (MAGG) and the MUSE Ultra Deep Field (MUDF), we detect significant emission out to approx 40 kpc, while and emission is detected out to approx 30 kpc. Via comparisons with the nearby average stellar continuum emission, we find that the line emission at 20--30 kpc likely arises from the disk-halo interface. Combining our results with that of our previous study at $z we find that the average surface brightness increases independently with redshift over $z and with stellar mass over which is likely driven by the star formation rate as well as the physical conditions of the gas. By comparing the observed line fluxes with photoionization models, we find that the ionization parameter declines with distance, going from log q (cm $) approx 7.7 at le 5 kpc to approx 7.3 at 20--30 kpc, which reflects a weaker radiation field in the outer regions of galaxies. The gas-phase metallicity shows no significant variation over 30 kpc, with a metallicity gradient of approx 0.003 dex kpc$^ $, which indicates an efficient mixing of metals on these scales. Alternatively, there could be a significant contribution from shocks and diffuse ionized gas to the line emission in the outer regions.

A design of compact plasmonic lens consisting of high index dielectric gratings and metal nano-film

In this paper, a hybrid ultra-thin planar subwavelength focusing structure consisting of a high refractive index dielectric grating and a nano metal film was designed. The thickness of this structure is only 200 nm. Surface plasmon polaritons (SPPs) were excited from the nano metal film, propagated along the metal-air interface, and were then converted into a radiation field by the dielectric grating, forming a focused spot in free space. By adjusting the grating position and width parameters, the shape of the focused optical field could be controlled. The simulation results showed that, under 532 nm light irradiation, the lens could produce a 270 nm (full width at half-maximum, FWHM) spot size at a focal length of 2.46λ. Moreover, under the illumination of 633 nm and 780 nm light, the designed lenses were found to produce focal spot sizes of 304 nm (0.48λ) and 364 nm (0.47λ), respectively, which were smaller than the diffraction limit. The simplicity of this plasmonic lens design, coupled with its reduced thickness and minimal absorption loss, offered significant advantages in terms of cost-effectiveness and ease of fabrication.

Numerical Simulation of Radiatively Driven Transonic Relativistic Jets

We perform the numerical simulations of axisymmetric, relativistic, optically thin jets under the influence of the radiation field of an accretion disk. We show that starting from a very low injection velocity at the base, jets can be accelerated to relativistic terminal speeds when traveling through the radiation field. The jet gains momentum through the interaction with the radiation field. We use a relativistic equation of state for multispecies plasma, which self-consistently calculates the adiabatic index for the jet material. All the jet solutions obtained are transonic in nature. In addition to the acceleration of the jet to relativistic speeds, our results show that the radiation field also acts as a collimating agent. The jets remain well collimated under the effect of radiation pressure. We also show that if the jet starts with a rotational velocity, the radiation field will reduce the angular momentum of the jet beam.

The eigenfunctions method in relation to diffuse reflection problems of the radiative energy transfer theory

Using the new method proposed earlier by the author, a solution of diffuse reflection problem is given in this report. A case of diffuse reflection of radiation from a semi-infinite absorbing and isotropically reflecting medium is presented, when in the elementary act of scattering there is a general law of redistribution of radiation by frequencies. In the approach presented here, conventionally called the method of ”decomposition of the resulting field” - DRF, in contrast to the previously widely used traditional method of ”decomposition of a single act” of scattering - DSA, the problem of diffuse reflection is solved without the use of any decomposition or special representation of the characteristic of the elementary act of scattering, i.e., the redistribution function of radiation by frequencies. The resulting radiation field, formed in the medium by means of multiple scatterings, is sought and constructed directly in the form of a bilinear series through a specially derived system of its own eigenfunctions. The physical basis of this approach lies in the fact that after each successive act of scattering, the field formed in the medium becomes more and more smoothed, so its direct representation in a decomposed form is more expedient than the traditionally used decomposition of a pre-known ”unsmoothed” characteristic of the elementary act of scattering.

Radiation and reaction at one loop

We study classical radiation fields at next-to-leading order using the methods of scattering amplitudes. The fields of interest to us are sourced when two massive, point-like objects scatter inelastically, and can be computed from one-loop amplitudes. The real and imaginary parts of the amplitudes play important but physically distinct roles in the radiation field. We argue that the imaginary part captures the effects of radiation reaction. This aspect of radiation reaction is directly linked to cuts of one-loop amplitudes which expose Compton trees. We also discuss the fascinating interplay between renormalisation, radiation reaction and classical field theory from this perspective.

Position-dependent Radiation Fields near Accretion Disks

In disk-wind models for active galactic nuclei outflows, high-energy radiation poses a significant problem wherein the gas can become overionized, effectively disabling what is often inferred to be the largest force acting on the gas: the radiation force due to spectral line opacity. Calculations of this radiation force depend on the magnitude of ionizing radiation, which can strongly depend on the position above a disk where the radiation is anisotropic. As our first step to quantify the position and direction dependence of the radiation field, we assumed free streaming of photons and computed energy distributions of the mean intensity and components of flux as well as energy-integrated quantities such as mean photon energy. We find a significant dependence of radiation-field properties on position, but this dependence is not necessarily the same for different field quantities. A key example is that the mean intensity is much softer than the radial flux at many points near the disk. Because the mean intensity largely controls ionization, this softening decreases the severity of the overionization problem. The position dependence of mean intensity implies the position dependence of gas opacity, which we illustrate by computing the radiation force a fluid element feels in an accelerating wind. We find that in a vertical accelerating flow, the force due to radiation is not parallel to the radiation flux. This misalignment is due to the force’s geometric weighting by both the velocity field’s directionality and the position dependence of the mean intensity.

High-energy Neutrinos from Outflows Powered by the Kicked Remnants of Binary Black Hole Mergers in Active Galactic Nucleus Accretion Disks

Merging of stellar-mass binary black holes (BBHs) could take place within the accretion disks of active galactic nuclei (AGN). The resulting BH remnant is likely to accrete the disk gas at a super-Eddington rate, launching a fast, quasi-spherical outflow (wind). Particles will be accelerated by shocks driven by the wind, subsequently interacting with the shocked disk gas or radiation field through hadronic processes and resulting in the production of high-energy neutrinos and potential electromagnetic (EM) emission. This study delves into the intricate evolution of the shock driven by a merged BH wind within an AGN disk. Subsequently, we calculated the production of neutrinos and the expected detection numbers for a single event, along with their contributions to the overall diffuse neutrino background. Our analysis, which considers various scenarios, reveals considerable neutrino production and possible detection by IceCube for nearby events. The contribution of merged BH winds on the diffuse neutrino background is minor due to the low event rate density, but it can be improved to some extent for some optimistic parameters. We also propose that there could be two neutrino/EM bursts, one originating from the premerger BBH wind and the other from the merged BH wind, with the latter typically having a delay to the gravitational wave (GW) event of around tens of days. When combined with the anticipated GWs emitted during the BBH merger, such a system emerges as a promising candidate for joint observations involving neutrinos, GWs, and EM signals.

Five narrow bands terahertz metamaterial absorber based on metal and Dirac semi-metal for high sensitivity refractive index sensing

A five narrow bands terahertz metamaterial absorber based on metal and Dirac semi-metal for high sensitivity refractive index sensing is designed in this paper. The absorber is a traditional sandwich structure. And the most remarkable difference is that two hybrid materials (metal and Dirac semi-metal) are used in the top layer. The numerical results show five absorption peaks can be achieved at 5.527, 5.759, 7.247, 9.257 and 10.186 THz, among which the perfect absorption achieve at 5.759, 7.247 and 10.186 THz, respectively. The physical mechanism of the proposed absorber is analyzed qualitatively and quantitatively by electric field distributions and couple-mode theory. In addition, the sensing application of the proposed absorber is also studied. The sensitivity of the sensing band can reach up to 3.89 THz/RIU by computation. Finally, we design a specific application scenario to ensure the accuracy of the absorber in application through calculation. We believe that the absorber we designed will shine brilliantly in the fields of thermal imaging, thermal radiation and photothermal detection.

Design and Development of a Portable Neutron Detection System Based on a 6Li-Doped ZnS(Ag) Scintillator

In this study, the design and development of a portable neutron detection system based on a 6LiF + ZnS(Ag) scintillator was carried out. The detector system was first modeled using the Monte Carlo simulation code MCNP. As a result of the detector simulation, the materials and photomultiplier tubes (PMTs) were supplied for the system, and the material properties and thicknesses were optimized for the best scintillator, with the EJ-420 (Eljen Technology), consisting of 95% 6Li dispersed in ZnS(Ag), chosen because it has a distinctive feature with regard to high thermal neutron detection efficiency. Since this material has been shown to offer a significant advantage in favor of neutron detection in mixed radiation fields with gammas and neutrons, the pulse shape discrimination method was employed. To achieve this, a proper electronic circuit was developed to discriminate the pulses from neutrons and gammas. In the experimental step, the EJ-420 scintillator with a 50-mm diameter was optically coupled with a special fast PMT (Hamamatsu H1949-51 model). In conclusion, this study, which underlines the performed simulations for a neutron detector configuration, gives the obtained experimental results showing discrimination capability in neutron/gamma detection using a 241Am-Be neutron source. The results show that the EJ-420 is a good scintillator due to its highly enriched 6Li transmator, which results in more effective neutron measurements when a portable neutron detector design is chosen.

New numerical models of atomic diffusion in the atmospheres of cool Ap stars, including ambipolar diffusion of hydrogen

Ambipolar diffusion of hydrogen gives an additional upward thrust to metals that diffuse in the atmosphere of Ap stars. Its quantitative effect on the build-up of abundance stratification due to atomic diffusion that produces the observed abundance anomalies in Ap stars has not been evaluated so far. The purpose of this work is to quantify this effect throughout the stratification process of metals inside the atmosphere. We used our code caratmotion to compute the time-dependent atomic diffusion of four metals (Mg, Ca, Si, and Fe) in the atmosphere of a main-sequence star with an effective temperature of $8\,500$\,K, which is a typical temperature of Ap stars. The results, including ambipolar diffusion of H, are compared to results obtained without this process. Our main result is that ambipolar diffusion must be included in any calculation of atomic diffusion in Ap star atmospheres, at least for stars with $T_ eff 10\,000$\,K. We show that this concerns all metals, even those that are well supported by the radiation field, such as Fe. The crucial role of the stellar mass-loss rate is confirmed; it remains a determining parameter that is constrained, but still free in our calculations. We also present 3D calculations of Ca distributions in magnetic atmospheres. Questioning the interest of systematic searches for stationary solutions (which can often only be reached after a long evolutionary process), we note that remarkable behaviour can occur during the transient phases of the stratification build-up.

PHANGS-MeerKAT and MHONGOOSE HI observations of nearby spiral galaxies: Physical drivers of the molecular gas fraction, Rmol

The molecular-to-atomic gas ratio is crucial to our understanding of the evolution of the interstellar medium (ISM) in galaxies. We investigated the balance between the atomic ( and molecular gas ( surface densities in eight nearby star-forming galaxies using new high-quality observations from MeerKAT and ALMA (for and CO, respectively). We defined the molecular gas ratio as mol and measured how depends on local conditions in the galaxy disks using multiwavelength observations. We find that, depending on the galaxy is detected at out to $20-120$\,kpc in galactocentric radius gal $). The typical radius at which reaches 1 is hi kpc, which corresponds to $1-3$ times the optical radius $). We note that, $R_ mol $ correlates best with the dynamical equilibrium pressure, P$_ DE $, among potential drivers studied, with a median correlation coefficient of $ Correlations between mol $ and the star formation rate surface density, total gas surface density, stellar surface density, metallicity, and (a proxy for the combined effect of the UV radiation field and number density) are present but somewhat weaker. Our results also show a direct correlation between and $ SFR $, supporting self-regulation models. Quantitatively, we measured similar scalings as previous works, and attribute the modest differences that we do find to the effect of varying resolution and sensitivity. At $r_ gal gtrsim 0.4 r_ $, atomic gas dominates over molecular gas among our studied galaxies, and at the balance of these two gas phases ($R_ mol $ = 1), we find that the baryon mass is dominated by stars, with Our study constitutes an important step in the statistical investigation of how local galaxy properties (stellar mass, star formation rate, or morphology) impact the conversion from atomic to molecular gas in nearby galaxies.

Emergence hour-by-hour of features in the kilonova AT2017gfo

The spectral features in the optical/near-infrared counterparts of neutron star mergers (kilonovae, KNe) evolve dramatically on hourly timescales. To examine the spectral evolution, we compiled a temporal series that was complete at all observed epochs from 0.5 to 9.4\,days of the best optical/near-infrared (NIR) spectra of the gravitational-wave detected kilonova AT2017gfo. Using our analysis of this spectral series, we show that the emergence times of spectral features place strong constraints on line identifications and ejecta properties, while their subsequent evolution probes the structure of the ejecta. We find that the most prominent spectral feature, the 1\ P Cygni line, appears suddenly, with the earliest detection at 1.17\,days. We find evidence in this earliest feature for the fastest yet discovered kilonova ejecta component at 0.40--0.45$c$. Across the observed epochs and wavelengths, the velocities of the line-forming regions span nearly an order of magnitude, down to as low as 0.04--0.07$c$. The time of emergence closely follows the predictions for because combines rapidly under local thermal equilibrium (LTE) conditions. The transition time between the doubly and singly ionised states provides the first direct measurement of the ionisation temperature. This temperature is highly consistent with the temperature of the emitted blackbody radiation field at a level of a few percent. Furthermore, we find the KN to be isotropic in temperature, that is, the polar and equatorial ejecta differ by less than a few hundred Kelvin or \( 5\)<!PCT!>, in the first few days post-merger based on measurements of the reverberation time-delay effect. This suggests that a model with very simple assumptions, with single-temperature LTE conditions, reproduces the early kilonova properties surprisingly well.

A real-sized start-up monitoring module prototype for comprehensive test and irradiation campaigns of miniaturized neutron detectors according to the IFMIF-DONES baseline

The key system to know the neutron and gamma fields during the commissioning at IFMIF-DONES facility will be the STart-Up Monitoring Module (STUMM), which will include tens of very sophisticated and miniaturised detectors providing crucial information about the radiation fields. In particular, there will be MFCs (micro-fission chambers), ICs (Ionisation Chambers), SPNDs (Self-Powered Neutron Devices) and GTs (Gamma Thermometers).The current state-of-the-art does not provide answers about the performance of the detectors in the very specific working conditions inside the IFMIF-DONES Test Cell, as a very high spatial density of detectors inside the STUMM vessel, an extremely harsh environment with neutron flux up to 5·1014n/cm2/s and the need of long mineral cables (>30 m) to drive the very weak current signals from the irradiation area to the closest electronics cubicles available in the facility.Except for the extremely high neutron flux provided by IFMIF-DONES, all the other very critical conditions can be replicated by means of a 1:1 scaled prototype of the STUMM (STUMM-PROTO), which will be subjected to comprehensive testing and irradiation campaigns in order to increase the knowledge about the performance of the detectors above mentioned.The present work shows the wide range of capabilities offered by STUMM-PROTO as well as the current status of its construction and some first notions about the experimental campaigns to be implemented.

Observational signatures of the dust size evolution in isolated galaxy simulations

We aim to provide observational signatures of the dust size evolution in the interstellar medium (ISM). In particular, we explore indicators of the polycyclic aromatic hydrocarbon (PAH) mass fraction ($q_ PAH $), defined as the mass fraction of PAHs relative to the total dust grains. In addition, we validate our dust evolution model by comparing the observational signatures from our simulations to observations. We used the hydrodynamic simulation code, GADGET4-OSAKA to model the dust properties of Milky Way-like and NGC 628-like galaxies representing star-forming galaxies. This code incorporates the evolution of grain size distributions driven by dust production and interstellar processing. Furthermore, we performed post-processing dust radiative transfer calculations with SKIRT based on the hydrodynamic simulations to predict the observational properties of the simulations. We find that the intensity ratio between 8 um and 24 um ($I_ nu um )/I_ nu um )$) is correlated with $q_ PAH $ and can be used as an indicator of the PAH mass fraction. However, this ratio is influenced by the local radiation field. We suggest the 8 um -to-total infrared intensity ratio ($ I_ nu um )/ I_ TIR $) as another indicator of the PAH mass fraction, since it is tightly correlated with the PAH mass fraction. Furthermore, we explored the spatially resolved evolutionary properties of the PAH mass fraction in the simulated Milky Way-like galaxy using $ I_ nu um )/ I_ TIR $. We find that the spatially resolved PAH mass fraction increases with metallicity at $Z due to the interplay between accretion and shattering, whereas it decreases at $Z because of coagulation. Also, coagulation decreases the PAH mass fraction in regions with a high hydrogen surface density. Finally, we compared the above indicators in the NGC 628-like simulation with those observed in NGC 628 by Herschel Spitzer and JWST . Consequently, we find that our simulation underestimates the PAH mass fraction throughout the entire galaxy by a factor of $ 8$ on average. This could be due to the efficient loss of PAHs by coagulation in our model, suggesting that our treatment of PAHs in dense regions needs to be improved.

Off-iso Winston-Lutz test on seven linear accelerators.

The aim of this study is to find optimal gantry, collimator, and couch angles for performing single isocenter, multiple target stereotactic radiosurgery (SIMT-SRS). Nineteen angle sets were tested across seven linear accelerators for radiation-isocenter coincidence and off-isocenter coincidence. The off-isocenter Winston-Lutz test was performed to evaluate the accuracy of isocenter alignment for each angle set, and optimal angle sets as well as maximum off-isocenter distance to target for each angle set was determined. The influence of simulated patient weight on off-iso Winston-Lutz test accuracy was also inspected. The SNC MultiMet-WL phantom and MultiMet-WL QA Software v2.1 were used for the direct measurement and analysis of the off-iso Winston-Lutz test (also referred to as Winston-Lutz-Gao test). A two-step method was developed to ensure precise initial placement of the target. Nineteen beams were delivered at 6X energy and 2×2cm field size to each of six targets on the MultiMet Cube with couch kicks at five cardinal angles (90°, 45°, 0°, 315°, and 270°). To reduce imaging uncertainty, only EPID was used in target alignment and test image acquisition. A total of 200Ibs (90.7kg) of weight was also used to mimic patient weight. All tests were performed on both the free table and the weighted table. For two new TrueBeam machines, the maximum offset was within the 1mm tolerance when the off-iso distance is less than 7cm. Two older VitalBeam machines exhibited unfavorable gantry, couch, and collimator (GCC) angle sets: Linac No. 3 at (0,90,0), (0,270,0) and Linac No. 4 at (0,45,45) and (0,90,0). The C-Series Linacs failed in the majority of GCC angle sets, with Linac No. 5 exhibiting a maximum offset of 1.53mm. Four of seven machines show a clear trend that offset increases with off-isocenter distance. Additionally, the IGRT table was less susceptible to the addition of simulated patient weight than the ExactCouch. Among the seven linear accelerators addressed, newer model machines such as the Varian TrueBeam were more precise than older models, especially in comparison to the C-Series Linacs. The newer machines are more suitable for delivering SIMT-SRS procedures in all GCC angle sets, and the results indicate that newer TrueBeams are capable of performing SIMT-SRS procedures at all angle sets for targets of off-iso distances up to 7cm. The trend that offset between the target center and radiation field center increases with off-iso distance, however, does not always hold true across machines. This may be comprised by the EPID's severe off-axis horn effect. Lastly, the IGRT couch was less susceptible to patient weight compared to ExactCouch in the off-isocenter Winston-Lutz test.

Multi-band enhanced nonreciprocal thermal radiation based on Weyl semimetals

Previous studies manifested that the majority of structures that exhibit nonreciprocal thermal radiation in the mid-infrared are capable of achieving either single-band strong nonreciprocity or multi-band weak nonreciprocity at a large incidence angle. However, few structures can realize multi-band strong nonreciprocity at a small incidence angle. To address such scientific issues, we propose a tunable nonreciprocal thermal emitter based on gallium arsenide (GaAs)/graphene/Weyl semimetal (WSM). This device is capable of achieving strong nonreciprocity at 7.3 μm, 10 μm and 13.6 μm wavelengths at an incidence angle of 25.5°. It is shown that the field enhancement of the GaAs/graphene composite layer can improve the nonreciprocal response of the WSM layer. In addition, by changing the Fermi energy level of graphene and the axial vector b of the Weyl semimetal, tunable nonreciprocal thermal radiation can be realized. What's more, we find that the structure breaks Kirchhoff's law without lithography and an external magnetic field, which reveals the advantages of applying our research in the field of thermal radiation.

Salvage Breast-Conserving Surgery and Reirradiation With Intraoperative Electrons for Recurrent Breast Cancer: A Multicentric Study on Behalf of Italian Association of Radiotherapy and Clinical Oncology

AimIntraoperative radiotherapy with electrons (IOERT) may represent a viable choice for partial breast re-irradiation (rePBI) after repeat quadrantectomy for local recurrence (LR) for primary breast cancer (BC) in lieu of mastectomy. Materials and MethodsA database collecting data on rePBI with IOERT from 8 Italian centres was set up in 2016- 2018, providing data on cumulative incidence (CumI) of 2nd LR nd survival with a long follow-up (FU) ResultsFrom 2002 to 2015, 109 patients underwent the conservative retreatment.The median primary BC -1stLR interval was 11.1 years (range: 2.4-27.7). The median 1stLR size was 0.9 cm (range: 0.3-3.0) and 43.6% were Luminal A. Median IOERT dose was 18 Gy (range: 12-21) and median collimator was 4 cm (range: 3-6). Median FU was 11.7 years (interquartile range: 7.7-14.6). The 2ndLR CumI was 12.2% (95% CI: 6.8-19.2) at 5 years and 32.3% at 10 years (95% CI: 22.8-42.2), occurring in the same site as the 1stLR in about half of the cases. HER2 status and collimator size were independent LR predictors. The 5- and 10-year overall survival were 95.2% and 88.3%, respectively, while 5- and 10-year BC specific survival were 98% and 94.5%. The development of a 2ndLR significantly reduced BCSS (HR=9.40, P<0.001). Grade ≥3 fibrosis was 18.9%. Patient-reported cosmesis was good/excellent in 59.7% of the cases. Conclusion2ndLR CumI was within the range of the literature, but higher than expected, opening questions on radiation field extension and fractionation schedule. Since a 2ndLR worsened the outcome, salvage modality must be carefully planned.

Local therapy in glioma: An evolving paradigm from history to horizons (Review).

Despite the implementation of multimodal treatments after surgery, glioblastoma (GBM) remains an incurable disease, posing a significant challenge in neuro-oncology. In this clinical setting, local therapy (LT), a developing paradigm, has received significant interest over time due to its potential to overcome the drawbacks of conventional therapy options for GBM. The present review aimed to trace the historical development, highlight contemporary advances and provide insights into the future horizons of LT in GBM management. In compliance with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols criteria, a systematic review of the literature on the role of LT in GBM management was conducted. A total of 2,467 potentially relevant articles were found and, after removal of duplicates, 2,007 studies were screened by title and abstract (Cohen's κ coefficient=0.92). Overall, it emerged that 15, 10 and 6 clinical studies explored the clinical efficiency of intraoperative local treatment modalities, local radiotherapy and local immunotherapy, respectively. GBM recurrences occur within 2 cm of the radiation field in 80% of cases, emphasizing the significant influence of local factors on recurrence. This highlights the urgent requirement for LT strategies. In total, three primary reasons have thus led to the development of numerous LT solutions in recent decades: i) Intratumoral implants allow the blood-brain barrier to be bypassed, resulting in limited systemic toxicity; ii) LT facilitates bridging therapy between surgery and standard treatments; and iii) given the complexity of GBM, targeting multiple components of the tumor microenvironment through ligands specific to various elements could have a synergistic effect in treatments. Considering the spatial and temporal heterogeneity of GBM, the disease prognosis could be significantly improved by a combination of therapeutic strategies in the era of precision medicine.

IW-NeRF: Using Implicit Watermarks to Protect the Copyright of Neural Radiation Fields

The neural radiance field (NeRF) has demonstrated significant advancements in computer vision. However, the training process for NeRF models necessitates extensive computational resources and ample training data. In the event of unauthorized usage or theft of the model, substantial losses can be incurred by the copyright holder. To address this concern, we present a novel algorithm that leverages the implicit neural representation (INR) watermarking technique to safeguard NeRF model copyrights. By encoding the watermark information implicitly, we integrate its parameters into the NeRF model’s network using a unique key. Through this key, the copyright owner can extract the embedded watermarks from the NeRF model for ownership verification. To the best of our knowledge, this is the pioneering implementation of INR watermarking for the protection of NeRF model copyrights. Our experimental results substantiate that our approach not only offers robustness and preserves high-quality 3D reconstructions but also ensures the flawless (100%) extraction of watermark content, thereby effectively securing the copyright of the NeRF model.