bluuebunny/crossref_metadata_2025_split huggingface dataset:
Organ motion in pediatric high‐risk neuroblastoma patients using four‐dimensional computed tomography
Authors: Kannan Sneha , Teo Boon‐Keng Kevin , Solberg Timothy , Hill‐Kayser Christine 
Published: October 2023

AbstractPurpose/objective(s)High‐risk neuroblastoma (HR‐NBL) requires multimodality treatment, including external beam radiation of the primary tumor site following resection. Radiotherapy planning must take into account motion of the target and adjacent normal anatomy, both of which are poorly understood in the pediatric population, and which may differ significantly from those in adults.Methods/materialsWe examined 4DCT scans of 15 consecutive pediatric patients treated for HR‐NBL, most with tumors in the abdominal cavity. The diaphragm and organs at risk were contoured at full inhale, full exhale, and on free‐breathing scans. Maximum displacement of organs between full inhale and full exhale was measured in the anterior, posterior, superior, inferior, left, and right directions, as was displacement of centroids in the A/P, S/I, and L/R axes. Contours on free‐breathing scans were compared to those on 4D scans.ResultsMaximum displacement was along the S/I axis, with the superior aspects of organs moving more than the inferior, implying organ compression with respiration. Liver and spleen exhibited the largest motion, which correlated strongly with the S/I motion of the diaphragm. The maximum organ motion observed in the abdomen and thorax were 4.5 mm and 7.4 mm, respectively, while maximum diaphragm displacement was 5.7 mm. Overall findings mirrored observations in adults, but with smaller magnitudes, as expected. No consistent margins could be added to the free‐breathing scans to encompass the motion determined using 4DCT.ConclusionsOrgan motion within the pediatric abdomen and pelvis is similar to that observed in adults, but with smaller magnitude. Precise margins to accommodate motion are patient‐specific, underscoring the need for 4DCT scanning when possible.
Evaluation of the TrueBeam machine performance check (MPC) beam constancy checks for flattened and flattening filter‐free (FFF) photon beams
Authors: Barnes Michael P , Greer Peter B 
Published: October 2023

AbstractMachine Performance Check (MPC) is an automated and integrated image‐based tool for verification of beam and geometric performance of the TrueBeam linac. The aims of the study were to evaluate the MPC beam performance tests against current daily quality assurance (QA) methods, to compare MPC performance against more accurate monthly QA tests and to test the sensitivity of MPC to changes in beam performance. The MPC beam constancy checks test the beam output, uniformity, and beam center against the user defined baseline. MPC was run daily over a period of 5 months (n = 115) in parallel with the Daily QA3 device. Additionally, IC Profiler, in‐house EPID tests, and ion chamber measurements were performed biweekly and results presented in a form directly comparable to MPC. The sensitivity of MPC was investigated using controlled adjustments of output, beam angle, and beam position steering. Over the period, MPC output agreed with ion chamber to within 0.6%. For an output adjustment of 1.2%, MPC was found to agree with ion chamber to within 0.17%. MPC beam center was found to agree with the in‐house EPID method within 0.1 mm. A focal spot position adjustment of 0.4 mm (at isocenter) was measured with MPC beam center to within 0.01 mm. An average systematic offset of 0.5% was measured in the MPC uniformity and agreement of MPC uniformity with symmetry measurements was found to be within 0.9% for all beams. MPC uniformity detected a change in beam symmetry of 1.5% to within 0.3% and 0.9% of IC Profiler for flattened and FFF beams, respectively.
Development and performance evaluation of a high‐speed multileaf collimator
Authors: Zhang Xiang , Ye Peiqing , Zhang Hui 
Published: October 2023

AbstractMultileaf collimator (MLC) tracking represents a promising technique for motion management in radiotherapy. However, the conflict between limited leaf speed/acceleration and the demand for tracking fast target motion is now a prominent issue. Conventional MLCs typically have a maximum leaf speed of 3–4 cm/s and a maximum leaf acceleration of 50–70 cm/s2, which are inadequate to track fast target motion. To cope with this problem, we have recently developed a high‐speed multileaf collimator (HS‐MLC) prototype, which employs linear motors instead of rotary motors to drive leaves. Consequently, it inherits various benefits of linear motors, including direct drive and high dynamics. The primary aim of this paper was to introduce the development and performance evaluation of the HS‐MLC. The evaluation includes Monte Carlo simulations of the basic dosimetric properties, camera‐based measurements of the mechanical properties and tracking experiments for 25 sets of patient‐measured motion data. The Monte Carlo simulation results show that the maximum leakage at 6MV is 1.29% and the average is 0.61%. The end‐to‐end leakage is 3.96% for 5 cm offset and is 1.75% for 10 cm offset. The penumbra for a standard 10 × 10 cm2 field ranges from 4.8 mm to 5.4 mm across the full range of leaf motion. The mechanical property measurements demonstrate that the maximum leaf speed is 40 cm/s, the maximum leaf acceleration is 1000 cm/s2, and the geometric accuracy can be kept within 0.5 mm. Regarding the tracking experiments for a wide range of motion patterns (fast breathing, irregular breathing, etc.), a root‐mean‐square error (RMSE) of less than 0.19 mm was achieved. In conclusion, the HS‐MLC is able to well track fast target motion that is beyond the capability of conventional MLCs due to its superior mechanical properties. The new MLC design provides a feasible solution to make high‐accuracy and high‐efficiency motion management possible.
Commissioning, clinical implementation, and performance of the Mobetron 2000 for intraoperative radiation therapy
Authors: Wootton Landon S. , Meyer Juergen , Kim Edward , Phillips Mark 
Published: October 2023

AbstractThe Mobetron is a mobile electron accelerator designed to deliver therapeutic radiation dose intraoperatively while diseased tissue is exposed. Experience with the Mobetron 1000 has been reported extensively. However, since the time of those publications a new model, the Mobetron 2000, has become commercially available. Experience commissioning this new model and 3 years of data from historical use are reported here. Descriptions of differences between the models are emphasized, both in physical form and in dosimetric characteristics. Results from commissioning measurements including output factors, air gap factors, percent depth doses (PDDs), and 2D dose profiles are reported. Output factors are found to have changed considerably in the new model, with factors as high as 1.7 being measured. An example lookup table of appropriate accessory/energy combinations for a given target dimension is presented, and the method used to generate it described. Results from 3 years of daily QA measurements are outlined. Finally, practical considerations garnered from 3 years of use are presented.
Helical tomotherapy to LINAC plan conversion utilizing RayStation Fallback planning
Authors: Zhang Xin , Penagaricano Jose , Narayanasamy Ganesh , Corry Peter , Liu TianXiao , Sanjay Maraboyina , Paudel Nava , Morrill Steven 
Published: October 2023

AbstractRaySearch RayStation Fallback (FB) planning module can generate an equivalent backup radiotherapy treatment plan facilitating treatment on other linear accelerators. FB plans were generated from the RayStation FB module by simulating the original plan target and organ at risk (OAR) dose distribution and delivered in various backup linear accelerators. In this study, helical tomotherapy (HT) backup plans used in Varian TrueBeam linear accelerator were generated with the RayStation FB module. About 30 patients, 10 with lung cancer, 10 with head and neck (HN) cancer, and 10 with prostate cancer, who were treated with HT, were included in this study. Intensity‐modulated radiotherapy Fallback plans (FB‐IMRT) were generated for all patients, and three‐dimensional conformal radiotherapy Fallback plans (FB‐3D) were only generated for lung cancer patients. Dosimetric comparison study evaluated FB plans based on dose coverage to 95% of the PTV volume (R95), PTV mean dose (Dmean), Paddick's conformity index (CI), and dose homogeneity index (HI). The evaluation results showed that all IMRT plans were statistically comparable between HT and FB‐IMRT plans except that PTV HI was worse in prostate, and PTV R95 and HI were worse in HN multitarget plans for FB‐IMRT plans. For 3D lung cancer plans, only the PTV R95 was statistically comparable between HT and FB‐3D plans, PTV Dmean was higher, and CI and HI were worse compared to HT plans. The FB plans using a TrueBeam linear accelerator generally offer better OAR sparing compared to HT plans for all the patients. In this study, all cases of FB‐IMRT plans and 9/10 cases of FB‐3D plans were clinically acceptable without further modification and optimization once the FB plans were generated. However, the statistical differences between HT and FB‐IMRT/3D plans might not be of any clinically significant. One FB‐3D plan failed to simulate the original plan without further optimization.
Room scatter effects in Total Skin Electron Irradiation: Monte Carlo simulation study
Authors: Nevelsky Alexander , Borzov Egor , Daniel Shahar , Bar‐Deroma Raquel 
Published: October 2023

AbstractPurposeTotal Skin Electron Irradiation (TSEI) is a complex technique which usually involves the use of large electron fields and the dual‐field approach. In this situation, many electrons scattered from the treatment room floor are produced. However, no investigations of the effect of scattered electrons in TSEI treatments have been reported. The purpose of this work was to study the contribution of floor scattered electrons to skin dose during TSEI treatment using Monte Carlo (MC) simulations.MethodsAll MC simulations were performed with the EGSnrc code. Influence of beam energy, dual‐field angle, and floor material on the contribution of floor scatter was investigated. Spectrum of the scattered electrons was calculated. Measurements of dose profile were performed in order to verify MC calculations.ResultsFloor scatter dependency on the floor material was observed (at 20 cm from the floor, scatter contribution was about 21%, 18%, 15%, and 12% for iron, concrete, PVC, and water, respectively). Although total dose profiles exhibited slight variation as functions of beam energy and dual‐field angle, no dependence of the floor scatter contribution on the beam energy or dual‐field angle was found. The spectrum of the scattered electrons was almost uniform between a few hundred KeV to 4 MeV, and then decreased linearly to 6 MeV.ConclusionsFor the TSEI technique, dose contribution due to the electrons scattered from the room floor may be clinically significant and should be taken into account during design and commissioning phases. MC calculations can be used for this task.
Effects of model size and composition on quality of head‐and‐neck knowledge‐based plans
Authors: Kaderka Robert , Dogan Nesrin , Jin William , Bossart Elizabeth 
Published: October 2023

AbstractPurposeKnowledge‐based planning (KBP) aims to automate and standardize treatment planning. New KBP users are faced with many questions: How much does model size matter, and are multiple models needed to accommodate specific physician preferences? In this study, six head‐and‐neck KBP models were trained to address these questions.MethodsThe six models differed in training size and plan composition: The KBPFull (n = 203 plans), KBP101 (n = 101), KBP50 (n = 50), and KBP25 (n = 25) were trained with plans from two head‐and‐neck physicians. KBPA and KBPB each contained n = 101 plans from only one physician, respectively. An independent set of 39 patients treated to 6000–7000 cGy by a third physician was re‐planned with all KBP models for validation. Standard head‐and‐neck dosimetric parameters were used to compare resulting plans. KBPFull plans were compared to the clinical plans to evaluate overall model quality. Additionally, clinical and KBPFull plans were presented to another physician for blind review. Dosimetric comparison of KBPFull against KBP101, KBP50, and KBP25 investigated the effect of model size. Finally, KBPA versus KBPB tested whether training KBP models on plans from one physician only influences the resulting output. Dosimetric differences were tested for significance using a paired t‐test (p < 0.05).ResultsCompared to manual plans, KBPFull significantly increased PTV Low D95% and left parotid mean dose but decreased dose cochlea, constrictors, and larynx. The physician preferred the KBPFull plan over the manual plan in 20/39 cases. Dosimetric differences between KBPFull, KBP101, KBP50, and KBP25 plans did not exceed 187 cGy on aggregate, except for the cochlea. Further, average differences between KBPA and KBPB were below 110 cGy.ConclusionsOverall, all models were shown to produce high‐quality plans. Differences between model outputs were small compared to the prescription. This indicates only small improvements when increasing model size and minimal influence of the physician when choosing treatment plans for training head‐and‐neck KBP models.
Utilization of an Artery‐on‐a‐Chip to Unravel Novel Regulators and Therapeutic Targets in Vascular Diseases
Authors: Paloschi Valentina , Pauli Jessica , Winski Greg , Wu Zhiyuan , Li Zhaolong , Botti Lorenzo , Meucci Sandro , Conti Pierangelo , Rogowitz Felix , Glukha Nadiya , Hummel Nora , Busch Albert , Chernogubova Ekaterina , Jin Hong , Sachs Nadja , Eckstein Hans‐Henning , Dueck Anne , Boon Reinier A. , Bausch Andreas R. , Maegdefessel Lars 
Published: October 2023

AbstractIn this study, organ‐on‐chip technology is used to develop an in vitro model of medium‐to‐large size arteries, the artery‐on‐a‐chip (AoC), with the objective to recapitulate the structure of the arterial wall and the relevant hemodynamic forces affecting luminal cells. AoCs exposed either to in vivo‐like shear stress values or kept in static conditions are assessed to generate a panel of novel genes modulated by shear stress. Considering the crucial role played by shear stress alterations in carotid arteries affected by atherosclerosis (CAD) and abdominal aortic aneurysms (AAA) disease development/progression, a patient cohort of hemodynamically relevant specimens is utilized, consisting of diseased and non‐diseased (internal control) vessel regions from the same patient. Genes activated by shear stress follow the same expression pattern in non‐diseased segments of human vessels. Single cell RNA sequencing (scRNA‐seq) enables to discriminate the unique cell subpopulations between non‐diseased and diseased vessel portions, revealing an enrichment of flow activated genes in structural cells originating from non‐diseased specimens. Furthermore, the AoC served as a platform for drug‐testing. It reproduced the effects of a therapeutic agent (lenvatinib) previously used in preclinical AAA studies, therefore extending the understanding of its therapeutic effect through a multicellular structure.
Exchange Bias Between van der Waals Materials: Tilted Magnetic States and Field‐Free Spin–Orbit‐Torque Switching
Authors: Cham Thow Min Jerald , Dorrian Reiley J. , Zhang Xiyue S. , Dismukes Avalon H. , Chica Daniel G. , May Andrew F. , Roy Xavier , Muller David A. , Ralph Daniel C. , Luo Yunqiu Kelly 
Published: October 2023

AbstractMagnetic van der Waals heterostructures provide a unique platform to study magnetism and spintronics device concepts in the 2D limit. Here, studies of exchange bias from the van der Waals antiferromagnet CrSBr acting on the van der Waals ferromagnet Fe3GeTe2 (FGT) are reported. The orientation of the exchange bias is along the in‐plane easy axis of CrSBr, perpendicular to the out‐of‐plane anisotropy of the FGT, inducing a strongly tilted magnetic configuration in the FGT. Furthermore, the in‐plane exchange bias provides sufficient symmetry breaking to allow deterministic spin–orbit torque switching of the FGT in CrSBr/FGT/Pt samples at zero applied magnetic field. A minimum thickness of the CrSBr of >10 nm is needed to provide a non‐zero exchange bias at 30 K.
Multimodal Tetrahedral DNA Nanoplatform for Surprisingly Rapid and Significant Treatment of Acute Liver Failure
Authors: Wei Hongyan , Yi Ke , Li Fenfang , Li Di , Yang Jiazhen , Shi Run , Jin Yuanyuan , Wang Haixia , Ding Jianxun , Tao Yu , Li Mingqiang 
Published: October 2023

AbstractAcute liver failure (ALF) is a life‐threatening disease associated with the rapid development of inflammatory storms, level elevation of reactive oxygen species (ROS), and hepatocyte necrosis, which results in high short‐term mortality. Except for liver transplantation, no effective strategies are available for ALF therapy due to the rapid disease progression and narrow window of therapeutic time. Therefore, there is an urgent demand to explore the fast and effective modalities for ALF treatment. Herein, a multifunctional tetrahedral DNA nanoplatform (TDN) is constructed by incorporating tumor necrosis factor‐α siRNA (siTNF‐α) through DNA hybridization and antioxidant manganese porphyrin (MnP4) via π–π stacking interaction with G‐quadruplex (G4) for surprisingly rapid and significant ALF therapy. TDN‐siTNF‐α/‐G4‐MnP4 silences TNF‐α of macrophages by siTNF‐α and polarizes them to the anti‐inflammatory M2 phenotype, providing appropriate microenvironments for hepatocyte viability. Additionally, TDN‐siTNF‐α/‐G4‐MnP4 scavenges intracellular ROS by MnP4, protecting hepatocytes from oxidative‐stress‐associated cell death. Furthermore, TDN itself promotes hepatocyte proliferation by modulating the cell cycle. TDN‐siTNF‐α/‐G4‐MnP4 shows almost complete liver accumulation after intravenous injection and exhibits excellent therapeutic efficacy of ALF within 2 h. The multifunctional DNA nanoformulation provides an effective strategy for rapid ALF therapy, expanding its application for innovative treatments of liver diseases.
Acetamide‐Caprolactam Deep Eutectic Solvent‐Based Electrolyte for Stable Zn‐Metal Batteries
Authors: Wang Shihe , Liu Ganxiong , Wan Wang , Li Xueyang , Li Ju , Wang Chao 
Published: October 2023

AbstractAqueous Zn‐ion batteries (AZIBs) are promising for grid‐scale energy storage. However, conventional AZIBs face challenges including hydrogen evolution reaction (HER), leading to high local pH, and by‐product formation on the anode. Hereby the hydrogen bonds in the aqueous electrolyte are reconstructed by using a deep eutectic co‐solvent (DES) made of acetamide (H‐bond donor) and caprolactam (H‐bond acceptor), which effectively suppresses the reactivity of water and broadens the electrochemical voltage stability window. The coordination between Zn2+ and acetamide‐caprolactam in DES‐based electrolytes produces a unique solvation structure that promotes the preferential growth of Zn crystals along the (002) plane. This will inhibit the formation of Zn dendrites and ensure the uniform deposition of Zn‐ions on the anode surface. In addition, it is found that this DES‐based electrolyte can form a protective membrane on the anode surface, reducing the risks of Zn corrosion. Compared to conventional electrolytes, the DES‐based electrolyte shows a long‐term stable plating/stripping performance with a significantly improved Coulombic efficiency from 78.18% to 98.37%. It is further demonstrated that a Zn||VS2 full‐cell with the DES‐based electrolyte exhibits enhanced stability after 500 cycles with 85.4% capacity retention at 0.5 A g−1.
Tunable Optical Forces Enabled by Bilayer van der Waals Materials
Authors: Cai Ziqiang , Jin Renchao , Xu Yihao , Liu Yongmin 
Published: October 2023

AbstractManipulation of nanoparticles by light induced forces is widely used in nanotechnology and bioengineering. In normal cases, when a nanoparticle is illuminated by light waves, the transfer of momentum from light to the nanoparticle can push it to move along the light propagation direction. On the other hand, the lateral optical force can transport an object perpendicular to the light propagation direction, and the optical pulling force can attract an object toward the light source. Although these optical forces have drawn growing attention, in situ tuning of them is rarely explored. In this paper, tuning of both lateral optical forces and optical pulling forces is numerically demonstrated via a graphene/α‐phase molybdenum trioxide (α‐MoO3) bilayer structure. Under plane‐wave illumination, both the amplitude and direction of the optical forces exerted on a nanoparticle above this bilayer structure can be tuned in the mid‐infrared range. The underlying mechanism can be understood by studying the corresponding isofrequency contours of the hybrid plasmon‐phonon polaritons supported by the graphene/α‐MoO3 bilayer. The analytical study using the dipole approximation method reproduces the numerical results, revealing the origin of the optical forces. This work opens a new avenue for engineering optical forces to manipulate various objects optically.
Stress‐Induced Multi‐Stimulus‐Responsive Mechanoluminescence in Mn2+ Doped Double Perovskite Compound
Authors: Wang Zhiduo , Xiao Yao , Liu Bingjun , Chen Kang , Shao Peishan , Chen Zhicong , Xiong Puxian , Gan Jiulin , Chen Dongdan 
Published: October 2023

AbstractMulti‐mode mechanoluminescence (ML) materials are have applications such as anti‐counterfeiting, stress sensing, and information security. There is limited general consensuses on the luminescent mechanisms, even though exploring ML mechanism based on defects has shown significance in further studies exploring both ML materials design and application. Here, a deep‐red to near‐infrared (NIR) ML material is reported in a Mn2+‐activated double perovskite‐type compound (CaZnGe2O6: Mn2+). The abundant lattice sites within the crystal structure have enabled Mn2+ doping and defects. Two different photoluminescence (PL) emission bands peaked at 536 and 676 nm from 4T1(4G)→6A1(6S) are observed, which are attributed to the substitution of Zn2+ and Ca2+ sites by Mn2+, respectively. Hence, tunable emissions from green to red are realized in single Mn2+ doping, which can be further regulated by varying the Mn2+ concentration. Electrons and holes are captured by cation and anion defects ( and , , vacancy of Zn, Ca and O ions), followed by the combination of such carriers to transfer energy to the Mn2+ 3d states to produce ML/persistent luminescence (PersL) under mechanical/thermal stimuli. Proof‐of‐concept applications in multi‐mode anti‐counterfeiting, temperature sensing, and X‐ray imaging fields are demonstrated. These results will deepen the understanding of single Mn2+‐doped multi‐stimulus‐responsive ML materials, inspiring the development of more high‐performance ML phosphors for practical applications.