bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantification of the role of lead foil in flattening filter free beam reference dosimetry
Authors: Gao Song , Nelson Christopher , Wang Congjun , Kathriarachchi Vindu , Choi Michael , Saxena Rishik , Kendall Robin , Balter Peter
Published: March 2023

Purpose

To quantify the potential error in outputs for flattening filter free (FFF) beams associated with use of a lead foil in beam quality determination per the addendum protocol for TG‐51, we examined differences in measurements of the beam quality conversion factor kQ when using or not using lead foil.

Methods

Two FFF beams, a 6 MV FFF and a 10 MV FFF, were calibrated on eight Varian TrueBeams and two Elekta Versa HD linear accelerators (linacs) according to the TG‐51 addendum protocol by using Farmer ionization chambers [TN 30013 (PTW) and SNC600c (Sun Nuclear)] with traceable absorbed dose‐to‐water calibrations. In determining kQ, the percentage depth‐dose at 10 cm [PDD(10)] was measured with 10×10 cm2 field size at 100 cm source‐to‐surface distance (SSD). PDD(10) values were measured either with a 1 mm lead foil positioned in the path of the beam [%dd(10)Pb] or with omission of a lead foil [%dd(10)]. The %dd(10)x values were then calculated and the kQ factors determined by using the empirical fit equation in the TG‐51 addendum for the PTW 30013 chambers. A similar equation was used to calculate kQ for the SNC600c chamber, with the fitting parameters taken from a very recent Monte Carlo study. The differences in kQ factors were compared for with lead foil vs. without lead foil.

Results

Differences in %dd(10)x with lead foil and with omission of lead foil were 0.9 ± 0.2% for the 6 MV FFF beam and 0.6 ± 0.1% for the 10 MV FFF beam. Differences in kQ values with lead foil and with omission of lead foil were −0.1 ± 0.02% for the 6 MV FFF and −0.1 ± 0.01% for the 10 MV FFF beams.

Conclusion

With evaluation of the lead foil role in determination of the kQ factor for FFF beams. Our results suggest that the omission of lead foil introduces approximately 0.1% of error for reference dosimetry of FFF beams on both TrueBeam and Versa platforms.
Diagnostic Yield of Computed Tomography for Cancer Detection in a Tertiary Referral Population of Idiopathic Inflammatory Myositis Patients
Authors: Mecoli Christopher A. , Chee Brant , Chen Mengkun , Wang XingYao , Albayda Jemima , Paik Julie J. , Tiniakou Eleni , Adler Brittany , Kelly Will , Mammen Andrew L. , Platz Elizabeth A. , Casciola‐Rosen Livia , Christopher‐Stine Lisa , Shah Ami A.
Published: March 2023

Objective

To inform guidance for cancer detection in patients with idiopathic inflammatory myopathy (IIM), we evaluated the diagnostic yield of computed tomography (CT) imaging for cancer screening/surveillance within distinct IIM subtypes and myositis‐specific autoantibody strata.

Methods

We conducted a single‐center, retrospective cohort study in IIM patients. Overall diagnostic yield (number of cancers diagnosed/number of tests performed), percentage of false positives (number of biopsies performed not leading to cancer diagnosis/number of tests performed), and test characteristics were determined on CT of the chest and abdomen/pelvis.

Results

Within the first 3 years since IIM symptom onset, a total of 9 of 1,011 (0.9%) chest CT scans and 12 of 657 (1.8%) abdomen/pelvis CT scans detected cancer. Diagnostic yields for both CT of the chest and CT of the abdomen/pelvis were highest in dermatomyositis, specifically anti–transcription intermediary factor 1γ (2.9% and 2.4% for CT of the chest and abdomen/pelvis, respectively). The highest percentage of false positives was in patients with antisynthetase syndrome (ASyS) (4.4%) and immune‐mediated necrotizing myopathy (4.4%) on CT of the chest, and ASyS (3.8%) on CT of the abdomen/pelvis. Patients ages <40 years old at IIM onset had both low diagnostic yields (0% and 0.5%) and high false‐positive rates (1.9% and 4.4%) for CT of the chest and abdomen/pelvis, respectively.

Conclusion

In a tertiary referral cohort of IIM patients, CT imaging has a wide range of diagnostic yield and frequency of false positives for contemporaneous cancer. These findings suggest that cancer detection strategies targeted according to IIM subtype, autoantibody positivity, and age may maximize cancer detection while minimizing the harms and costs of over‐screening.
A New Candidate in Polyanionic Compounds for Potassium Ion Battery Anode: MXene Derived Carbon Coated π‐Ti2O(PO4)2
Authors: Sun Xuan , Li Zhujie , Liu Zixin , Lv Xiaowei , Shi Keqing , Chen Renjie , Wu Feng , Li Li
Published: March 2023

Intercalation‐type reaction that occurs in polyanion materials is considered to be a facile way to counter the mismatched relationship between the large K+ and compact host structure for potassium ion batteries (PIBs). However, the large “dead” weight and poor conductivity introduced by the polyanion framework severely limit the electrochemical performance of polyanion anodes. Herein, a new rigid K+ host of 1D π‐Ti2O(PO4)2 with carbon‐coated (TOP@C) is simply synthesized through a simple Ti3C2Tx‐derived method. The density functional theory (DFT) calculations and experimental results show that the potassium storage properties are unquestionably improved by the small cell volume change during cycling, the intercalation pseudo‐capacitance energy storage mechanism, and the large K‐storage tunnels with lower migration energy (0.23 eV) of TOP@C anode (134.5 mAh g‐1 after 2000 cycles at 1.0 A g‐1). The TOP@C//PTCDA full batteries, which clearly illustrate their promising application in advanced PIBs, successfully achieved a high energy density of 119.4 Wh kg‐1 and a power density up to 632.8 W kg‐1 with regard to the total mass of TOP@C and PTCDA.