scholarly journals The use of radioactive substances in medicine — history and development prospects

2021 ◽  
Vol 67 (6) ◽  
pp. 59-67
Author(s):  
M. S. Sheremeta ◽  
A. A. Trukhin ◽  
M. O. Korchagina
Keyword(s):  
Nuclear Medicine ◽  
Gamma Ray ◽  
Clinical Medicine ◽  
Radiation Energy ◽  
Medical Specialty ◽  
80Th Anniversary ◽  
Genomic Technologies ◽  
Alpha Emission ◽  
Medicine History ◽  
Development Prospects

Nuclear medicine (NM) is a medical specialty that uses radionuclides (radioactive tracers) and ionising radiation for diagnostic and therapeutic (theranostic) purposes. Nuclear medicine arose and developed at the intersection of physics, chemistry and clinical medicine. The radiation emitted by radioisotopes can consist of gamma-, beta- and alpha emission, or it’s combination. Radioisotope of choice for medical purposes should have futher requirements: low radiotoxicity, suitable type of radiation, energy and half-life (several minutes to several hours and days), and also convenient detection of gamma ray radiation. The radionuclide is part of radiopharmaceutical (RP) and acts as its indicator. RP accumulates in morphological structures, becomes a carrier of coordinated information from patient to gamma camera or other equipment and reflects the dynamics of processes occurring in the examined organ. In 2021 NM celebrates its 80th anniversary. The trajectory of NM combines modern methods of radiotheranostics and applied genomic and post-genomic technologies.

The effect of gamma ray penetration on angle-dependent sensitivity for pinhole collimation in nuclear medicine

1997 ◽  
Vol 24 (11) ◽  
pp. 1701-1709 ◽  
Author(s):  
Mark F. Smith ◽  
Ronald J. Jaszczak
Keyword(s):  
Nuclear Medicine ◽  
Gamma Ray

scholarly journals Developments in New Measurements of Fission Cross-Sections, Fragment Yields, and Prompt and Quasi-Prompt Gammas for Nuclear Data Needs

2020 ◽  
Vol 242 ◽  
pp. 01002
Author(s):  
Adam Hecht ◽  
Phoenix Baldez ◽  
Baldez Baldez
Keyword(s):  
Cross Sections ◽  
Ionization Chamber ◽  
Gamma Ray ◽  
Fission Products ◽  
Product Yield ◽  
Nuclear Data ◽  
University Of New Mexico ◽  
Alpha Emission ◽  
Time Projection ◽  
The University

The University of New Mexico Fission Spectrometer was developed to measure fission product yield, as part of the LANL SPIDER collaboration. The spectrometer operates as an E-v detector to extract product mass event-by-event, with a time of flight region followed by an ionization chamber for kinetic energy measurements. By using the ionization chamber as a singlecathode/single-anode time projection chamber, stopping power and thus Z information is extracted, for coupled A and Z measurements. New work is being performed to add gamma ray detectors in the data stream, placed near the target region for prompt gammas and near the ionization chamber for quasiprompt (>50 ns) and later gammas, correlated with individual fission products. A stand-alone parallel plate ionization chamber (PPIC) is also being developed for fission tagging gamma ray data. The PPIC will also allow discrimination between charged particle out events and (n,n’γ), and discriminate between alpha emission and fission. Using layers in the PPIC, other targets can be measured simultaneously with a calibration target, giving relative fission cross sections. Past measurements with the spectrometer were performed at LANSCE and we plan to continue measurements there. The current work is supported by the NNSA Stewardship Science Academic Alliance.

scholarly journals Analysis of national trends in neurosurgical resident attrition

2019 ◽  
Vol 131 (5) ◽  
pp. 1668-1673 ◽  
Author(s):  
Nitin Agarwal ◽  
Michael D. White ◽  
Susan C. Pannullo ◽  
Lola B. Chambless
Keyword(s):  
Residency Training ◽  
Clinical Medicine ◽  
Medical Specialty ◽  
Attrition Rate ◽  
Junior Resident ◽  
Advanced Degree ◽  
Attrition Rates ◽  
Medical Specialties ◽  
Targeted Interventions ◽  
Significant Difference

OBJECTIVEResident attrition creates a profound burden on trainees and residency programs. This study aims to analyze trends in resident attrition in neurological surgery.METHODSThis study followed a cohort of 1275 residents who started neurosurgical residency from 2005 to 2010. Data obtained from the American Association of Neurological Surgeons (AANS) included residents who matched in neurosurgery during this time. Residents who did not finish their residency training at the program in which they started were placed into the attrition group. Residents in the attrition group were characterized by one of five outcomes: transferred neurosurgery programs; transferred to a different specialty; left clinical medicine; deceased; or unknown. A thorough internet search was conducted for residents who did not complete their training at their first neurosurgical program. Variables leading to attrition were also analyzed, including age, sex, presence of advanced degree (Ph.D.), postgraduate year (PGY), and geographical region of program.RESULTSResidents starting neurosurgical residency from 2005 to 2010 had an overall attrition rate of 10.98%. There was no statistically significant difference in attrition rates among the years (p = 0.337). The outcomes for residents in the attrition group were found to be as follows: 33.61% transferred neurosurgical programs, 56.30% transferred to a different medical specialty, 8.40% left clinical medicine, and 1.68% were deceased. It was observed that women had a higher attrition rate (18.50%) than men (10.35%). Most attrition (65.07%) occurred during PGY 1 or 2. The attrition group was also observed to be significantly older at the beginning of residency training, with a mean of 31.69 years of age compared to 29.31 in the nonattrition group (p < 0.001). No significant difference was observed in the attrition rates for residents with a Ph.D. (9.86%) compared to those without a Ph.D. (p = 0.472).CONCLUSIONSA majority of residents in the attrition group pursued training in different medical specialties, most commonly neurology, radiology, and anesthesiology. Factors associated with an increased rate of attrition were older age at the beginning of residency, female sex, and junior resident (PGY-1 to PGY-2). Resident attrition remains a significant problem within neurosurgical training, and future studies should focus on targeted interventions to identify individuals at risk to help them succeed in their medical careers.

Comparative Study of Various Nuclear Medicine Imaging Technique - A Review

2021 ◽  
Vol 7 (3) ◽  
Author(s):  
Beena Ullala Mata B N ◽  
Anup Kumar Pal ◽  
Hrithik Sivadasan ◽  
Himanshu Mishra
Keyword(s):  
Nuclear Medicine ◽  
Multimodality Imaging ◽  
Imaging Techniques ◽  
Medical Specialty ◽  
Pharmacological Action ◽  
Individual Member ◽  
Nuclear Medicine Imaging ◽  
Pet Ct ◽  
Nuclear Medicine Instrumentation ◽  
The Impact

Nuclear Medicine is a medical specialty that allows modern diagnostics and treatments using radiopharmaceuticals original radiotracers (drugs linked to a radioactive isotope). The radiopharmaceuticals are considered a special group of drugs and thus their preparation and use are regulated by a set of policies that have been adopted by individual member countries. The radiopharmaceuticals used in diagnostic examinations are administered in very small doses. So, in general, they have no pharmacological action, side effects or serious adverse reactions. The most serious issue with their use is the potential for diagnostic mistakes due to changes in their biodistribution. The appearance and development of new radiopharmaceuticals in both the diagnostic and therapeutic domains, as well as the impact of new multimodality imaging techniques, are all having a significant impact on nuclear medicine (SPECT-CT, PET-CT, PET-MRI, etc.). It is crucial to understand the techniques limitations, radiopharmaceutical distribution and potential physiological changes, radiological contrast contraindications and bad responses, and the possibility of both interfering. The process of generating radiopharmaceuticals is introduced and relevant interactions of radiation with matter are discussed. Diagnostic nuclear medicine instrumentation is explained, and future trends in nuclear medicine imaging technology are forecasted.

scholarly journals AXPs & SGRs: Magnetar or Quarctar?

2012 ◽  
Vol 8 (S291) ◽  
pp. 474-476
Author(s):  
Guojun Qiao ◽  
Xionwei Liu ◽  
Renxin Xu ◽  
Yuanjie Du ◽  
Jinlin Han ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Magnetic Field Strength ◽  
Loss Rate ◽  
Gamma Ray ◽  
Radiation Energy ◽  
X Ray ◽  
Two Factors ◽  
Normal Method ◽  
The Magnetic Field

AbstractThe concept of a “magnetar” was proposed mainly because of two factors. First, the X-ray luminosity of Anomalous X-ray Pulsars (AXPs) and Soft Gamma-Ray Repeaters (SGRs) is larger than the rotational energy loss rate (Lx > Ėrot), and second, the magnetic field strength calculated from “normal method” is super strong. It is proposed that the radiation energy of magnetar comes from its magnetic fields. Here it is argued that the magnetic field strength calculated through the normal method is incorrect at the situation Lx > Ėrot, because the wind braking is not taken into account. Besides, the “anti-magnetar” and some other X-ray and radio observations are difficult to understand with a magnetar model.Instead of the magnetar, we propose a “quarctar”, which is a crusted quark star in an accretion disk, to explain the observations. In this model, the persistent X-ray emission, burst luminosity, spectrum of AXPs and SGRs can be understood naturally. The radio-emitting AXPs, which are challenging the magnetar, can also be explained by the quarctar model.

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