1
|
Mulherkar R, Ling DC, Tendulkar R, Kamrava MR, Beriwal S. Quality of Radiotherapy Workforce Training within the USA. Clin Oncol (R Coll Radiol) 2024:S0936-6555(24)00048-7. [PMID: 38331669 DOI: 10.1016/j.clon.2024.01.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 01/04/2024] [Accepted: 01/25/2024] [Indexed: 02/10/2024]
Abstract
The training, competency requirements and scope of practice of professionals within a radiation oncology department vary across countries. The purpose of this review is to shed light on the current status of radiotherapy training in the USA by discussing current benchmarks for medical residency, physics residency, radiation therapy and dosimetry training programmes. Although there are notable strengths, the US radiotherapy workforce training system also faces several challenges when it comes to standardising education to develop a competent workforce that meets societal needs. Continued efforts are needed at a systemic level to improve training in areas such as brachytherapy and proton therapy, promote research involvement and develop trainees who are equipped to form a competent radiation therapy workforce.
Collapse
Affiliation(s)
- R Mulherkar
- Department of Radiation Oncology, UPMC Hillman Cancer Center, Pittsburgh, PA, USA
| | - D C Ling
- Department of Radiation Oncology, USC Keck School of Medicine, Los Angeles, CA, USA
| | - R Tendulkar
- Department of Radiation Oncology, Cleveland Clinic Cancer Center, Cleveland, OH, USA
| | - M R Kamrava
- Department of Radiation Oncology, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - S Beriwal
- Department of Radiation Oncology, AHN Cancer Institute, Pittsburgh, PA, USA.
| |
Collapse
|
2
|
Jiao C, Ling DC, Bian SX, Vassantachart A, Cheng K, Mehta S, Lock D, Feng M, Thomas H, Scholey J, Sheng K, Fan Z, Yang W. Contouring Analysis on Synthetic Contrast-Enhanced MR from GRMM-GAN and Implications on MR-Guide Radiation Therapy. Int J Radiat Oncol Biol Phys 2023; 117:S117. [PMID: 37784304 DOI: 10.1016/j.ijrobp.2023.06.450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) MR-guided linear accelerators have been commercialized making MR-only planning and adaptation an appealing alternative circumventing MR-CT registration. However, obtaining daily contrast-enhanced MR images can be prohibitive due to the increased risk of side effects from repeated contrast injections. In this work, we evaluate the quality of contrast-enhanced multi-modal MR image synthesis network GRMM-GAN (gradient regularized multi-modal multi-discrimination sparse-attention fusion generative adversarial network) for MR-guided radiation therapy. MATERIALS/METHODS With IRB approval, we trained the GRMM-GAN based on 165 abdominal MR studies from 65 patients. Each study included T2, T1 pre-contrast (T1pre), and T1 contrast enhanced (T1ce) images. The two pre-contrast MR modalities, T2 and T1pre images were adopted as inputs for GRMM-GAN, and the T1ce image at the portal venous phase was used as an output. Ten MR scans containing 21 liver tumors were selected for contouring analysis. A Turing test was first given to six radiation oncologists, in which 100 real T1ce and synthetic T1ce image slices are randomly given to the radiation oncologists to determine the authenticity of the synthesis. We then invited two radiation oncologists (RadOnc 1 and RadOnc2) to manually contour the 21 liver tumors independently on the real T1ce images. RadOnc2 then performed contouring on the respective synthetic T1ce MRs. DICE coefficient (defined as the intersection over the average of two volumes) and Hausdorff distance (HD, measuring how far two volumes are from each other) were used as analysis metrics. The DICE coefficients were calculated from the two radiation oncologists' contours on the real T1ce MR for each tumor. The DICE coefficients were also calculated from RadOnc 2's contours on real and synthetic MRs. Besides, tumor center shifts were extracted. The tumor center of mass coordinates was extracted from real and synthetic volumes. The difference in the coordinates indicated the shifts in the superior-inferior (SI), right-left (RL), and anterior-posterior (AP) directions between real and synthetic tumor volumes. RESULTS An average of 52.3% test score was achieved from the six radiation oncologists, which is close to random guessing. RadOnc 1 and RadOnc 2, who had participated in the contouring analysis, achieved an average DICE of 0.91±0.02 from tumor volumes drawn on the real T1ce MRs. This result sets the inter-operator uncertainty baseline in the real clinical setting. RadOnc 2 achieved an average DICE (real vs. synth) of 0.90±0.04 and HD of 4.76±1.82 mm. Only sub-millimeter (SI: 0.67 mm, RL: 0.41 mm, AP: 0.39 mm) tumor center shifts were observed in all three directions. CONCLUSION The GRMM-GAN method has the potential for MR-guided liver radiation when contrast agents cannot be administered daily and provide synthetic contrast-enhanced MR for better tumor targeting. The network can produce synthetic MR images with satisfactory contour agreement and geometric integrity.
Collapse
Affiliation(s)
- C Jiao
- University of California, San Francisco, San Francisco, CA
| | - D C Ling
- University of Southern California, Los Angeles, CA
| | - S X Bian
- University of Southern California, Los Angeles, CA
| | - A Vassantachart
- Department of Radiation Oncology, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - K Cheng
- Department of Radiation Oncology, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - S Mehta
- Department of Radiation Oncology, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - D Lock
- University of Southern California, Los Angeles, CA
| | - M Feng
- University of California, San Francisco, San Francisco, CA
| | - H Thomas
- University of California, San Francisco, San Francisco, CA
| | - J Scholey
- University of California, San Francisco, San Francisco, CA
| | - K Sheng
- University of California, San Francisco, San Francisco, CA
| | - Z Fan
- University of Southern California, Los Angeles, CA
| | - W Yang
- University of California, San Francisco, San Francisco, CA
| |
Collapse
|
3
|
Deshpande NG, Weng CH, Wang YF, Shao YC, Ling DC, Hsueh HC, Du CH, Pong WF. The electronic and magnetic properties of strained La 0.85Zr 0.15MnO 3films. Acta Crystallogr A Found Adv 2014. [DOI: 10.1107/s2053273314097745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The electronic and magnetic properties of strained tetravalent-ion-doped La0.85Zr0.15MnO3 (LZMO) thin films that were epitaxially grown on SrTiO3 (STO) and MgO substrates were studied using temperature-dependent x-ray diffraction (XRD), x-ray absorption near-edge structure (XANES), x-ray linear dichroism (XLD) and x-ray magnetic circular dichroism (XMCD) at the Mn L3,2- and K-edge. XRD studies reveal that the LZMO thin films have compressive and tensile strains on the STO and MgO substrates, respectively. As temperature is reduced from room temperature to below magnetic transition temperature, the preferentially occupied Mn majority-spin eg orbital changes from the in-plane dx2-y2 to the out-of-plane d3z2-r2 orbital for LZMO/STO, and vice versa for LZMO/MgO. Experimental results suggest that the new hopping path that is mediated by the Mn2+ ions triggers a stronger d3z2-r2 orbital ordering of Mn3+ ions and enhances the ferromagnetic coupling between the Mn spin moments of t2g electrons in LZMO/STO, whereas the tensile strain stabilizes the dx2-y2 orbital by inducing lattice distortions of the MnO6 octahedra in LZMO/MgO.
Collapse
|
4
|
Tang CC, Lin HT, Wu SL, Chen TJ, Wang MJ, Ling DC, Chi CC, Chen JC. An interchangeable scanning Hall probe/scanning SQUID microscope. Rev Sci Instrum 2014; 85:083707. [PMID: 25173276 DOI: 10.1063/1.4893647] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We have constructed a scanning probe microscope for magnetic imaging, which can function as a scanning Hall probe microscope (SHPM) and as a scanning SQUID microscope (SSM). The scanning scheme, applicable to SHPM and SSM, consists of a mechanical positioning (sub) micron-XY stage and a flexible direct contact to the sample without a feedback control system for the Z-axis. With the interchangeable capability of operating two distinct scanning modes, our microscope can incorporate the advantageous functionalities of the SHPM and SSM with large scan range up to millimeter, high spatial resolution (⩽4 μm), and high field sensitivity in a wide range of temperature (4.2 K-300 K) and magnetic field (10(-7) T-1 T). To demonstrate the capabilities of the system, we present magnetic images scanned with SHPM and SSM, including a RbFeB magnet and a nickel grid pattern at room temperature, surface magnetic domain structures of a La(2/3)Ca(1/3)MnO3 thin film at 77 K, and superconducting vortices in a striped niobium film at 4.2 K.
Collapse
Affiliation(s)
- Chiu-Chun Tang
- Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Hui-Ting Lin
- Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Sing-Lin Wu
- Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Tse-Jun Chen
- Institute of Astronomy and Astrophysics, Academia Sinica, Taipei 10617, Taiwan
| | - M J Wang
- Institute of Astronomy and Astrophysics, Academia Sinica, Taipei 10617, Taiwan
| | - D C Ling
- Department of Physics, Tamkang University, Tamsui Dist., New Taipei City 25137, Taiwan
| | - C C Chi
- Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Jeng-Chung Chen
- Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan
| |
Collapse
|
5
|
Wong WCW, Yim YL, Leung TN, Lynn H, Ling DC. Prevalence and risk factors of sexually transmitted infections in female sex workers in Hong Kong. Hong Kong Med J 2012; 18 Suppl 3:42-46. [PMID: 22865224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023] Open
Affiliation(s)
- W C W Wong
- Department of Community and Family Medicine, School of Public Health and Primary Care, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong SAR, China.
| | | | | | | | | |
Collapse
|
6
|
Liu MT, Ray SC, Tsai HM, Pao CW, Ling DC, Pong WF, Chiou JW, Tsai MH, Jang LY, Pi TW, Lee JF, Lin CY, Chin TS. Correlation between magnetic properties and the electronic structures of soft magnetic ternary Fe(78-x)Y(x)B(22) (x = 4-9) bulk metallic glasses. J Phys Condens Matter 2008; 20:465105. [PMID: 21693839 DOI: 10.1088/0953-8984/20/46/465105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Fe and Y K-edge extended x-ray absorption fine structure, Fe(Y) L(3,2)-edge (L(3)-edge) x-ray absorption near-edge structure (XANES) and valence-band photoemission spectroscopy (VB-PES) measurements have been carried out to study soft magnetic ternary Fe(78-x)Y(x)B(22) bulk metallic glasses (BMGs). The combined XANES and VB-PES results do not show broadening of the Fe 3d band to support the previous interpretation of the reduction of the magnetic moment in BMGs by Y-induced decrease of exchange splitting of Fe 3d orbitals. Instead, the density of delocalized/itinerant Fe 3d states in the vicinity of the Fermi level is found to be reduced by Y substitution, which reduces the strength of itinerant-states-mediated ferromagnetic coupling between local spins on the Fe ions and the total magnetic moment of the Fe-based BMGs.
Collapse
Affiliation(s)
- M T Liu
- Department of Physics, Tamkang University, Tamsui 251, Taiwan
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Liang KC, Liu HL, Yang HD, Mei WN, Ling DC. Structural and optical studies of high dielectric constant (Na(0.5)A(0.5))Cu(3)Ti(4)O(12) (A = La and Bi). J Phys Condens Matter 2008; 20:275238. [PMID: 21694399 DOI: 10.1088/0953-8984/20/27/275238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We report x-ray powder diffraction and temperature-dependent infrared reflectivity measurements of (Na(0.5)La(0.5))Cu(3)Ti(4)O(12) and (Na(0.5)Bi(0.5))Cu(3)Ti(4)O(12) in order to investigate the origin of their lower room-temperature dielectric constants in comparison with the giant value of CaCu(3)Ti(4)O(12). Substituting Ca with Na/La or Na/Bi is found to decrease all Ti-O-Ti angles by the TiO(6) octahedra tilts, resulting in an increase of the local structural disorder on the Na/La and Na/Bi compounds. Further, several infrared-active phonon modes show a broadening in their linewidths, reflecting that the coherency in these vibrational modes is degraded by disorder. Additionally, the lowest-frequency mode of the Ca material is observed to strengthen dramatically at low temperatures, but to a lesser extent in the Na/La and Na/Bi compounds. These results suggest the important role of the local structural disorder on the anomalous low-frequency dielectric response in these materials.
Collapse
Affiliation(s)
- K-C Liang
- Department of Physics, National Taiwan Normal University, Taipei 116, Taiwan
| | | | | | | | | |
Collapse
|
8
|
Huang DJ, Lin HJ, Okamoto J, Chao KS, Jeng HT, Guo GY, Hsu CH, Huang CM, Ling DC, Wu WB, Yang CS, Chen CT. Charge-orbital ordering and Verwey transition in magnetite measured by resonant soft X-ray scattering. Phys Rev Lett 2006; 96:096401. [PMID: 16606287 DOI: 10.1103/physrevlett.96.096401] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2005] [Indexed: 05/08/2023]
Abstract
We report experimental evidence for the charge-orbital ordering in magnetite below the Verwey transition temperature T(V). Measurements of O K-edge resonant x-ray scattering on magnetite reveal that the O 2p states in the vicinity of the Fermi level exhibit a charge-orbital ordering along the c axis with a spatial periodicity of the doubled lattice parameter of the undistorted cubic phase. Such a charge-orbital ordering vanishes abruptly above T(V) and exhibits a thermal hysteresis, correlating closely with the Verwey transition in magnetite.
Collapse
Affiliation(s)
- D J Huang
- National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Ling DC, Chen JT, Wenger LE. Microwave-induced dc voltages in a YBa2Cu3O7- delta single crystal. Phys Rev B Condens Matter 1996; 53:15300-15304. [PMID: 9983327 DOI: 10.1103/physrevb.53.15300] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
10
|
Ling DC, Yong G, Chen JT, Wenger LE. Experimental Evidence for Intra- and Inter-Unit-Cell Josephson Junctions in a YBa2Cu3O7- delta Single Crystal. Phys Rev Lett 1995; 75:2011-2014. [PMID: 10059186 DOI: 10.1103/physrevlett.75.2011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
|
11
|
Ling DC, Luckett DJ, Darvey NL, Ding XL. A cost-based index of anther culture response in diverse wheat-breeding germplasm. ACTA ACUST UNITED AC 1995. [DOI: 10.1071/ea9950395] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Anther culture response in a diverse range of Australian wheat-breeding genotypes was tested and expressed as a 'culturability index' based on the actual costs of the various laboratory procedures. When the delay from harvest to plating was up to 12 h, the use of low dose gamma irradiation did not increase the anther culture response in this array of genotypes. This is in contrast to previous findings for which spike harvesting, irradiation, and plating was completed within 3 h and the irradiation treatment increased the anther culture response. Internal contamination of immature spike explants with Fusarium poae caused significant loss of cultures and may be a persistent problem for cereal anther culture. For the genotypes producing green regenerants, costs ranged from $A1.40 to $85/green regenerant.
Collapse
|