The various uses and applications of nuclear forensic science are examined. Nuclear forensic science is especially useful in determining the isotopic makeup, morphology and chemical purification of ...uranium and plutonium, among other applications.
The paper describes the application of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for the isotopic analysis of individual uranium-oxide particles. The procedure developed ...is suitable for the accurate measurement of
234U,
235U,
236U and
238U isotopes in single actinide particles with lateral dimensions down to 10
μm. The
235U/
238U isotope ratios can be obtained with a precision of a few percent relative standard deviation using a single collector ICP-MS instrument. The precision could be improved by the use of slow ablation and by taking several LA-ICP-MS replicate spectra on the same particle investigated. For the minor isotopes use of higher mass resolution (
R
=
4000) was necessary in some cases to avoid spectral interferences. The technique developed offers a rapid and accurate possibility for the isotopic composition determination of uranium-containing individual particles in environmental and safeguards samples.
A reliable and accurate laser ablation multi-collector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) method was developed for analysis of inhomogeneous samples containing uranium ...particles or aggregates of various enrichments. For the method development, a mixed solid standard was prepared using 1% and 3%
235
U enriched certified reference materials. After screening and localization of the particles of interest, the U isotopic composition was analysed for a 5-µm sample spot determining accurately and precisely the various constituents. Besides the LA-MC-ICP-MS, the standard was also measured by large-geometry secondary ion mass spectrometry (LG-SIMS) for additional verification.
In the framework of the European Commission Support Programme to the International Atomic Energy Agency (EC SP task A1753) 20 samples were obtained from the Dolní Rožínka (DIAMO, Czech Republic) ...uranium milling facility. The sampling procedure followed stepwise the uranium production and purification from the U ore to uranium ore concentrate (yellow cake) end-product. Elemental concentrations, rare-earth elemental pattern, anion concentrations, morphology and isotope abundance ratios of S, Sr, Pb and U were measured at each sampling stage. The purpose of the measurements was to investigate the applicability of various material characteristics for authentication, propagation and variation of these parameters, and to identify the relevant signatures for nuclear forensics and safeguards during the uranium production.
An improved and novel sample preparation method for
241Am analysis by inductively coupled plasma sector field mass spectrometry has been developed. The procedure involves a selective CaF
2 ...pre-concentration followed by an extraction chromatographic separation using TRU™ resin. The achieved absolute detection limit of 0.86
fg (0.11
mBq) is comparable to that of alpha spectrometry (0.1
mBq) and suitable for low-level environmental measurements. Analysis of different kinds of environmental standard reference materials (IAEA-384 – Fangataufa lagoon sediment, IAEA-385 – Irish Sea sediment and IAEA-308 – Mixed seaweed from the Mediterranean Sea) and alpha spectrometry were used to validate the procedure. The chemical recovery of sample preparation ranged between 72 and 94%. The results obtained are in good agreement with reference values and those measured by alpha spectrometry. The proposed method offers a rapid and less labor-intensive possibility for environmental
241Am analysis than the conventionally applied radioanalytical techniques.
Roses are one of the oldest and perhaps most noble and beautiful plants in the world. The propagation of roses by stem cutting is the simplest and a largely used method to multiply them. For the ...present experiment, seven varieties of roses were selected as follows: ‘Monika’, ‘Mr. Lincoln’, ‘Queen Elisabeth’, ‘The Fairy’, ‘Peace’, ‘King’s Ransom’, and ‘Don Juan’. To assess the differences between the varieties, growth, root length, root number, and frost damage were determined. The aim of the experiment is to determine which rose varieties are better suited to propagation by cuttings, which varieties have a higher rooting tendency, and to what extent the rooting could be influenced by rooting hormones Incit-8 (0.8% of 1-Naphthaleneacetic acid) and Radi-Stim
. From our results, it could be determined that the Incit-8 positively influenced the number of roots of all varieties. In conclusion, our research suggests that the rooting hormones increase the rooting of the rose varieties; moreover, that proper rooting could also be depending on the appropriate conditions.
A novel and simple analytical procedure has been developed for the trace-level determination of lanthanides (rare-earth elements) in uranium-bearing materials by inductively coupled plasma ...sector-field mass spectrometry (ICP-SFMS). The method involves a selective extraction chromatographic separation of lanthanides using TRU™ resin followed by ICP-SFMS analysis. The limits of detection of the method proposed is in the low pg
g
−1 range, which are approximately two orders of magnitude better than that of without chemical separation. The method was validated by the measurement of reference material and applied for the analysis of uranium ore concentrates (yellow cakes) for nuclear forensic purposes, as a potential application of the methodology.
Urban sprawl related increase of built-in areas requires reliable monitoring methods and remote sensing can be an efficient technique. Aerial surveys, with high spatial resolution, provide detailed ...data for building monitoring, but archive images usually have only visible bands. We aimed to reveal the efficiency of visible orthophotographs and photogrammetric dense point clouds in building detection with segmentation-based machine learning (with five algorithms) using visible bands, texture information, and spectral and morphometric indices in different variable sets. Usually random forest (RF) had the best (99.8%) and partial least squares the worst overall accuracy (~60%). We found that >95% accuracy can be gained even in class level. Recursive feature elimination (RFE) was an efficient variable selection tool, its result with six variables was like when we applied all the available 31 variables. Morphometric indices had 82% producer’s and 85% user’s Accuracy (PA and UA, respectively) and combining them with spectral and texture indices, it had the largest contribution in the improvement. However, morphometric indices are not always available but by adding texture and spectral indices to red-green-blue (RGB) bands the PA improved with 12% and the UA with 6%. Building extraction from visual aerial surveys can be accurate, and archive images can be involved in the time series of a monitoring.
Gastric cancer ranks as the fifth most common cancer globally. The presence of lymph node metastasis is a significant prognostic factor influencing survival. Postoperative morbidity and nodal staging ...accuracy are heavily affected by the extent of lymph node dissection. Our study aimed to explore the potential integration of two contemporary methods, sentinel node navigation surgery (SNNS) and the Maruyama Computer Program (MCP), to improve the accuracy of nodal staging.
We conducted a prospective data collection involving patients with gastric adenocarcinoma from 2008 to 2018 at the Department of Surgery, University of Debrecen, Hungary. Data from 100 consecutive patients were collected. The primary and secondary endpoints included evaluating the rate of node-negative patients and the diagnostic accuracy of our combined approach.
Sentinel node mapping was successful in 97 out of 100 patients. We found that using the threshold value of the Maruyama Index (MI) ≥ 28, all metastatic stations of sentinel-node-negative patients could be identified. Our method achieved 100% sensitivity and negative predictive value, with a specificity of 60.42% (95% CI = 46.31%-72.98%).
The combined application of SNNS and MCP has proven to be an effective diagnostic technique in the synergistic approach for identifying metastasis-positive lymph node stations. Despite its limitations, this combination may assist clinicians in customizing lymphadenectomy for gastric cancer patients.
Background
The focus of this study was to analyze the prognostic value of different combinations of inflammatory and coagulation factors using preoperative blood and to appraise the clinical ...importance of these biomarkers in colorectal cancer patients.
Methods
A prospective, multicenter study included patients undergoing radical colorectal surgery in three county hospitals. Inflammatory and coagulation markers were analyzed preoperatively.
Results
Two hundred and one patients were included. We examined patients based on their tumor localization. Colon cancer group involved patients with the tumor localized in the colon (n = 105, 52.24%) and rectal cancer group the patients with the tumor in the rectum (n = 96, 47.76%). Examining coagulation factors, univariate Cox analysis of colon cancer patients showed that activated partial thromboplastin time (p = 0.020) was significantly associated with overall survival, but we could not prove it in multivariate analysis. In colon cancer patients, neutrophil‐to‐lymphocyte ratio (NLR, p < 0.001) was positively correlated with tumor size and had significant association (χ2 = 5.48, p = 0.019, df = 1) with perineural invasion. Univariate and multivariate Cox analysis of colon cancer patients showed that NLR (p = 0.011 and p = 0.048) was significantly associated with disease‐free survival (DFS).
Conclusion
NLR was proved to be an independent prognostic factor for DFS in patients with non‐metastatic colon cancer. NLR might help to recognize the high‐risk patients between patients with the same tumor‐node‐metastasis stage and could help with the decision on adjuvant chemotherapy. Since the biomarkers in preoperative blood tests are habitually evaluated, NLR could be an inexpensive prognostic marker that can be easily assessed in clinical practice.
Neutrophil‐to‐lymphocyte ratio (NLR) was proved to be an independent prognostic factor for disease‐free survival in patients with non‐metastatic colon cancer in our Hungarian multicenter study. NLR might help to recognize the high‐risk patients between patients with the same tumor‐node‐metastasis stage and could help with the decision on adjuvant chemotherapy. The biomarkers in preoperative blood tests are habitually evaluated, and NLR could be an inexpensive prognostic marker that can be easily assessed in clinical practice.
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