• Title/Summary/Keyword: Safety Library

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Application of peak based-Bayesian statistical method for isotope identification and categorization of depleted, natural and low enriched uranium measured by LaBr3:Ce scintillation detector

  • Haluk Yucel;Selin Saatci Tuzuner;Charles Massey
    • Nuclear Engineering and Technology
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    • v.55 no.10
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    • pp.3913-3923
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    • 2023
  • Todays, medium energy resolution detectors are preferably used in radioisotope identification devices(RID) in nuclear and radioactive material categorization. However, there is still a need to develop or enhance « automated identifiers » for the useful RID algorithms. To decide whether any material is SNM or NORM, a key parameter is the better energy resolution of the detector. Although masking, shielding and gain shift/stabilization and other affecting parameters on site are also important for successful operations, the suitability of the RID algorithm is also a critical point to enhance the identification reliability while extracting the features from the spectral analysis. In this study, a RID algorithm based on Bayesian statistical method has been modified for medium energy resolution detectors and applied to the uranium gamma-ray spectra taken by a LaBr3:Ce detector. The present Bayesian RID algorithm covers up to 2000 keV energy range. It uses the peak centroids, the peak areas from the measured gamma-ray spectra. The extraction features are derived from the peak-based Bayesian classifiers to estimate a posterior probability for each isotope in the ANSI library. The program operations were tested under a MATLAB platform. The present peak based Bayesian RID algorithm was validated by using single isotopes(241Am, 57Co, 137Cs, 54Mn, 60Co), and then applied to five standard nuclear materials(0.32-4.51% at.235U), as well as natural U- and Th-ores. The ID performance of the RID algorithm was quantified in terms of F-score for each isotope. The posterior probability is calculated to be 54.5-74.4% for 238U and 4.7-10.5% for 235U in EC-NRM171 uranium materials. For the case of the more complex gamma-ray spectra from CRMs, the total scoring (ST) method was preferred for its ID performance evaluation. It was shown that the present peak based Bayesian RID algorithm can be applied to identify 235U and 238U isotopes in LEU or natural U-Th samples if a medium energy resolution detector is was in the measurements.

Evaluation of the CNESTEN's TRIGA Mark II research reactor physical parameters with TRIPOLI-4® and MCNP

  • H. Ghninou;A. Gruel;A. Lyoussi;C. Reynard-Carette;C. El Younoussi;B. El Bakkari;Y. Boulaich
    • Nuclear Engineering and Technology
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    • v.55 no.12
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    • pp.4447-4464
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    • 2023
  • This paper focuses on the development of a new computational model of the CNESTEN's TRIGA Mark II research reactor using the 3D continuous energy Monte-Carlo code TRIPOLI-4 (T4). This new model was developed to assess neutronic simulations and determine quantities of interest such as kinetic parameters of the reactor, control rods worth, power peaking factors and neutron flux distributions. This model is also a key tool used to accurately design new experiments in the TRIGA reactor, to analyze these experiments and to carry out sensitivity and uncertainty studies. The geometry and materials data, as part of the MCNP reference model, were used to build the T4 model. In this regard, the differences between the two models are mainly due to mathematical approaches of both codes. Indeed, the study presented in this article is divided into two parts: the first part deals with the development and the validation of the T4 model. The results obtained with the T4 model were compared to the existing MCNP reference model and to the experimental results from the Final Safety Analysis Report (FSAR). Different core configurations were investigated via simulations to test the computational model reliability in predicting the physical parameters of the reactor. As a fairly good agreement among the results was deduced, it seems reasonable to assume that the T4 model can accurately reproduce the MCNP calculated values. The second part of this study is devoted to the sensitivity and uncertainty (S/U) studies that were carried out to quantify the nuclear data uncertainty in the multiplication factor keff. For that purpose, the T4 model was used to calculate the sensitivity profiles of the keff to the nuclear data. The integrated-sensitivities were compared to the results obtained from the previous works that were carried out with MCNP and SCALE-6.2 simulation tools and differences of less than 5% were obtained for most of these quantities except for the C-graphite sensitivities. Moreover, the nuclear data uncertainties in the keff were derived using the COMAC-V2.1 covariance matrices library and the calculated sensitivities. The results have shown that the total nuclear data uncertainty in the keff is around 585 pcm using the COMAC-V2.1. This study also demonstrates that the contribution of zirconium isotopes to the nuclear data uncertainty in the keff is not negligible and should be taken into account when performing S/U analysis.

Cupping Therapy for the Treatment of Migraine Headache: a systematic review and meta-analysis of clinical trials

  • Bushra Mohandes;Fatma Elsayed Ahmed Bayoumi;Aisha Abdulkarim AllahDiwaya;Maryam Salah Falah;Leen Hesham Alhamd;Razan Abid Alsawadi;Yipeng Sun;Aidi Ma;Idris Sula;Muhammad Candragupta Jihwaprani
    • Journal of Pharmacopuncture
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    • v.27 no.3
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    • pp.177-189
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    • 2024
  • Objectives: Cupping therapy is a widely used complementary medicine for the treatment of migraine headaches globally. However, conflicting evidence exists on its effectiveness. To evaluate the safety and efficacy of cupping therapy in treating migraine headache disorder. Methods: Seven databases were systematically searched: PubMed/MEDLINE, Clinicaltrials.gov, Cochrane CENTRAL, ScienceDirect, ProQuest, SinoMed, and the National Science and Technology Library. The primary endpoints are the treatment success and the pain intensity reduction. The secondary endpoints were adverse events (AEs) risk and improvement in quality of life (QoL), which was based on the Migraine Disability Scale (MIDAS). Subgroup analyses were performed based on the cupping techniques (wet and dry cupping) and adjunctive complementary treatments (i.e. acupuncture and/or collateral pricking). Results: Eighteen trials out of 348 records were included, pooling 1,446 participants (n = 797 received cupping therapy). Treatment success was significantly higher among those with cupping therapy (risk ratio [RR] [95% CI] = 1.83 [1.52-2.21]); with significant improvement observed only with wet cupping (RR [95% CI] = 1.88 [1.53-2.30]). The adjunctive complementary therapy did not achieve a greater amplitude of treatment success compared to cupping therapy alone. Furthermore, cupping therapy showed significant pain reduction compared to baseline (standardized mean difference [SMD] [95% CI] = 0.55 [0.39-0.70]) and achieved fewer risks of AEs (RR [95% CI] = 1.88 [1.53-2.30]). However, cupping did not improve the overall QoL (MIDAS SMD [95% CI] = -0.79 [-3.55-1.98]). Conclusion: Cupping therapy was an effective complementary modality to treat migraine headaches. However, it did not demonstrate improvement in QoL (PROSPERO: CRD42024514509).

A Review of the Systemic Analysis Method on Dental Sedation for Children (소아 치과환자에 대한 진정법의 체계적 분석 방법 고찰)

  • An, Soyoun;Lee, Jewoo;Kim, Seungoh;Kim, Jongbin
    • Journal of the korean academy of Pediatric Dentistry
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    • v.42 no.4
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    • pp.331-339
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    • 2015
  • The first priority of sedation for incorporative children in pediatric dentistry is a safety. Therefore, evidence-based practices in health care are needed for preventing medical accidents. In accordance with the rise of the evidence based medicine, the interest in Evidence-Based Dentistry is increasing in the field of dentistry. However, systematic research about Evidence-Based sedation in Korea has rarely been done. As such, the purpose of this systematic review is to critically analyze the available scientific literature regarding dental sedation and to seek the next developmental strategies about evidence based pediatric dental sedation. A broad search of the 5 databases of the systematic reviews manual of the National Evidence-based Healthcare Collaborating Agency in Korea were referenced: 1) Core search database- KMbase, KISS; 2) Academic information and portal; 3) the National Assembly Library; 4) DBpia, and 5) RISS. Of a total 470 themes limited to the search term of "dental sedation", in accordance with the PRISMA statement for reporting systematic reviews of health sciences interventions, a literature selection process, which includes the removal of overlapping down the flow chart, was performed. Of the remaining 31 articles, two authors read through articles independently and added or removed articles using the exclusion criteria. Finally, twenty published papers of acceptable quality were identified and reviewed. This systemic review of Korean pediatric dental sedation practices for the last twenty-five years was based on the objective criteria defined in the GRADE process and identified consistent evidence. The results were evidence of moderate quality. Therefore, more systemically well-designed clinical studies are needed about the safe use of a sedative medicines (drugs).